Journal articles on the topic 'Coordinated Multi-Point (CoMP)'

In this paper, a coordinated multipoint joint transmission (CoMP-JT) framework at mmWave for a cyclic prefix (CP)-free multiuser OFDM wireless communication system is developed and analyzed. The aim is to provide high-quality service to cell-edge users; otherwise, the cell-users would suffer from significant signal degradation due to undesired interference. The impact of complex Hadamard transform with block diagonalization channel precoding for multiuser interference reduction and designed subcarrier mapping for out-of-band (OOB) reduction are investigated. In addition, the paper studied the input back-off-aided high-power amplifier for peak-to-average power ratio (PAPR) reduction and forward error correction channel coding for improved bit error rate (BER) for cell-edge users at mmWave frequencies. Moreover, signal-to-interference-noise ratio and ergodic achievable rate are estimated both in the presence and absence of CoMP-JT-based transmission technique to verify their significance in terms of transmitted power. Numerical investigations showed an OOB reduction of 312 dB, PAPR reduction from 17.50 dB to 7.66 dB, and improved BER of 1×10−3 in 16-QAM for a signal-to-noise ratio of −6 dB. Hence, the simulation results demonstrated the effectiveness of the developed system.

Joint Processing (JP) in Coordinated Multi-Point (CoMP) transmission allows user data to be jointly processed by several interfering base stations to achieve high performance and large capacity gain. This is achieved by making use of timing advance mechanisms; to ensure that the desired signals from the cooperating cells reach the mobile station at exactly the same time. The Joint Leakage Suppression (JLS) precoder is a suitable linear precoding scheme in this scenario. In this paper, JLS performance analysis is considered under real assumptions such as the presence of asynchronous reception of the interfering signals and the effect of the finite capacity backhaul links. The effect of quantizing the feedback channel on the sum rate is derived, and a tight upper bound of the rate loss due to quantization is obtained. Simulation results are provided to validate these results.

We propose a low-complexity carrier frequency offset (CFO) estimation approach and an independent component analysis (ICA) based semi-blind equalization structure for the orthogonal frequency division multiplexing (OFDM) based multiuser coordinated multi-point (CoMP) systems. A group of orthogonal sequences are employed to enable separation and simultaneous estimation of multiple CFOs at base stations, dividing a complex multi-dimensional search into series of low-complexity mono-dimensional searches. Then, a small number of pilot symbols attached to the source data, are used to resolve the ambiguity problem in the ICA equalized signals. It has a low complexity, as the permutation and quadrature ambiguity can be eliminated simultaneously, rather than sequentially by the previous precoding aided method. Simulation results show that the proposed semi-blind equalization structure has a bit error rate (BER) performance close to the ideal cases of the zero forcing (ZF) and minimum mean square error (MMSE) based equalization with perfect channel state information (CSI) and no CFO, and also significantly outperforms the constant amplitude zero autocorrelation (CAZAC) sequences based CFO estimation method.

For the upcoming 4G systems, network multiple-input multiple-output (MIMO) and inter-cell interference coordination (ICIC) are two of key techniques adopted in 4G systems to mitigate the serious inter-cell interference (ICI) and improve coverage and cell-edge throughput. Network MIMO is referred to as coordinated multi-point (CoMP) in LTE-A. In this paper, we propose a simulation platform to analyze the handover issue for downlink CoMP transmissions in LTE-A cellular systems. Among the variety of ICIC strategies, we apply the widely adopted soft frequency reuse (SFR) and the fractional frequency reuse (FFR) schemes. Both schemes are based on the idea of applying a frequency reuse factor of one in cell-center areas, and a higher reuse factor in cell-edge areas. Therefore, the ICI is reduced at the expense of the available frequency resources for each cell.

Due to the high splitting-gain of dense small cells, Ultra-Dense Network (UDN) is regarded as a promising networking technology to achieve high data rate and low latency in 5G mobile communications. In UDNs, each User Equipment (UE) may receive signals from multiple Base Stations (BSs), which impose severe interference in the networks and in turn motivates the possibility of using Coordinated Multi-Point (CoMP) transmissions to further enhance network capacity. In CoMP-based Ultra-Dense Networks, a great challenge is to tradeoff between the gain of network throughput and the worsening backhaul latency. Caching popular files on BSs has been identified as a promising method to reduce the backhaul traffic load. In this paper, we investigated content placement strategies and user association algorithms for the proactive caching ultra dense networks. The problem has been formulated to maximize network throughput of cell edge UEs under the consideration of backhaul load, which is a constrained non-convex combinatorial optimization problem. To decrease the complexity, the problem is decomposed into two suboptimal problems. We first solved the content placement algorithm based on the cross-entropy (CE) method to minimize the backhaul load of the network. Then, a user association algorithm based on the CE method was employed to pursue larger network throughput of cell edge UEs. Simulation were conducted to validate the performance of the proposed cross-entropy based schemes in terms of network throughput and backhaul load. The simulation results show that the proposed cross-entropy based content placement scheme significantly outperform the conventional random and Most Popular Content placement schemes, with with 50% and 20% backhaul load decrease respectively. Furthermore, the proposed cross-entropy based user association scheme can achieve 30% and 23% throughput gain, compared with the conventional N-best, No-CoMP, and Threshold based user association schemes.

<span style="color: black; font-family: 'Times New Roman','serif'; font-size: 9pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA; mso-bidi-font-style: italic;">This paper addresses the energy efficiency (EE) based user-association problem in cloud radio-access network. In specific, a low-complexity 2-stage iterative algorithm is developed for this purpose by jointly employing the coordinated multi-point (CoMP) and user-clustering techniques. The first stage of the algorithm applies a greedy search to form user-cluster and activate corresponded remote radio heads (RRHs) for CoMP transmission, only an RRH j with good channel gain could be included in the serving cluster of user k. Next, in the second stage, a re-clustering procedure is utilized to mitigate inter-cluster interference (ICI) and assign optimal power for scheduled users. Our obtained findings confirm that the transmit power, RRH density, and the number of users served by these RRHs can significantly affect the EE. Also, the results show that under certain system settings the proposed scheme can enhance the EE by almost 39.6% compared to conventional CoMP without user clustering technique.</span>

Unmanned Aerial Vehicle (UAV) has been widely used in various applications of wireless network. A system of UAVs has the function of collecting data, offloading traffic for ground Base Stations (BSs) and illuminating coverage holes. However, inter-UAV interference is easily introduced because of the huge number of LoS paths in the air-to-ground channel. In this paper, we propose an interference management framework for UAV-assisted networks, consisting of two main modules: power control and UAV clustering. The power control is executed first to adjust the power levels of UAVs. We model the problem of power control for UAV networks as a non-cooperative game which is proved to be an exact potential game and the Nash equilibrium is reached. Next, to further improve system user rate, coordinated multi-point (CoMP) technique is implemented. The cooperative UAV sets are established to serve users and thus transforming the interfering links into useful links. Affinity propagation is applied to build clusters of UAVs based on the interference strength. Simulation results show that the proposed algorithm integrating power control with CoMP can effectively reduce the interference and improve system sum-rate, compared to Non-CoMP scenario. The law of cluster formation is also obtained where the average cluster size and the number of clusters are affected by inter-UAV distance.

With the rapid proliferation of wireless traffic and the surge of various data-intensive applications, the energy consumption of wireless networks has tremendously increased in the last decade, which not only leads to more CO2 emission, but also results in higher operating expenditure. Consequently, energy efficiency (EE) has been regarded as an essential design criterion for future wireless networks. This paper investigates the problem of EE maximisation for a cooperative heterogeneous network (HetNet) powered by hybrid energy sources via joint base station (BS) switching (BS-Sw) and power allocation using combinatorial optimisation. The cooperation among the BSs is achieved through a coordinated multi-point (CoMP) technique. Next, to overcome the complexity of combinatorial optimisation, Lagrange dual decomposition is applied to solve the power allocation problem and a sub-optimal distance-based BS-Sw scheme is proposed. The main advantage of the distance-based BS-Sw is that the algorithm is tuning-free as it exploits two dynamic thresholds, which can automatically adapt to various user distributions and network deployment scenarios. The optimal binomial and random BS-Sw schemes are also studied to serve as benchmarks. Further, to solve the non-fractional programming component of the EE maximisation problem, a low-complexity and fast converging Dinkelbach’s method is proposed. Extensive simulations under various scenarios reveal that in terms of EE, the proposed joint distance-based BS-Sw and power allocation technique applied to the cooperative and harvesting BSs performs around 15–20% better than the non-cooperative and non-harvesting BSs and can achieve near-optimal performance compared to the optimal binomial method.

Context. From an astrometric point of view, quasars constitute the best and almost ideal reference objects in the celestial sphere, with a priori no significant proper motion. Since the third release of the Large Quasar Astrometric Catalogue (LQAC-3), a large number of quasars have been discovered, in particular those coming from the DR12Q release of the SDSS. Moreover, for cross-matched objects, we have taken advantage of the very accurate determinations of the quasars identified within the recent Gaia DR1 catalogue. Aims. Following the same procedure as in the three previous releases of the LQAC, our aim is to compile the large majority of all the quasars recorded so far. Our goal is to record their best coordinates and substantial information concerning their physical properties such as the redshift as well as multi-bands apparent and absolute magnitudes. Emphasis is given to the results of the cross-matches with the Gaia DR1 catalogue. Methods. New quasars coming from the DR12Q release were cross-matched with the precedent LQAC-3 compilation with a 1′′ search radius, in order to add the objects without counterpart to the LQAC-4 compilation. A similar cross-match was done with Gaia DR1 to identify the known quasars detected by Gaia. This enables one to improve significantly the positioning of these objects, and in parallel to study the astrometric performance of the individual catalogues of the LQAC-4 compilation. Finally, a new method was used to determine absolute magnitudes. Results. Our final catalogue, called LQAC-4, contains 443 725 objects. This is roughly 37.82% more than the number of objects recorded in the LQAC-3. Among them, 249 071 were found in common with the Gaia DR1, with a 1′′ search radius. That corresponds to 56.13% of the whole population in the compilation. Conclusions. The LQAC-4 delivers to the astronomical community a nearly complete catalogue of spectroscopically confirmed quasars (including a small proportion of compact AGNs), with the aim of giving their best equatorial coordinates with respect to the ICRF2 and with exhaustive additional information. For more than 50% of the sample, these coordinates come from the very recent Gaia DR1.

In recent years, due to the increase in providers of orbit and clock corrections of satellites for data evaluation in real-time and post-processing the method of Precise Point Positioning (PPP) using measurements of Global Navigation Satellite System (GNSS) and Web-based online positioning services have become widespread. Owing to some advantages, such as work-duration and cost-effectiveness, many of users have implemented PPP method instead of the traditional relative positioning method for several applications. On GNSS applications the quality of satellite ephemerides products used for data evaluation is a significant factor that affects the results in post-processing solutions either applying relative or PPP methods on analyses. These products, classified as ultra-rapid, rapid and final orbits, are regularly provided by several national and international organizations to the users. In this paper, the accuracy of PPP method has been studied comparing the outcomes from various online Web services using different software and satellite ephemerides products. For this purpose, three test points were established in a place with completely free satellite visibility (AC01) and on the other two places with partially (YC01) and vastly (KC01) prevention of satellite signals near and within a forest area at Campus of Davutpaşa of the Yildiz Technical University in Istanbul. At these stations, static observations have been conducted with a time span of 6 hours on 4th May 2015. The dataset collected using Topcon HiperPro receiver, a receiver for GPS and GLONASS data, was evaluated manually by means of the Bernese v5.2 (BSW) and GIPSY-OASIS v6.3 (Gipsy) scientific software. Moreover, the GNSS data were also proceeded using six different Web-based online services (AUSPOS, OPUS, CSRS-PPP, APPS, GAPS, Trimble-RTX) with ultra-rapid, rapid and final satellite ephemerides products. For the station with free satellite visibility (AC01), the analyses of outcomes indicate a coordinate accuracy of 1 cm for Web-based and manual data processing. That suggests relative good quality of orbit and clock corrections of satellites used by online data processing services for PPP. Furthermore, for station with partially (YC01) prevention of satellite signals, manual solutions have approximately 1 cm coordinate accuracies for n, e and u components. Moreover, when we compare the results among Web-based services, AUSPOS in relative solution and TrimbleRTX in PPP solution provides the best results. Here, one must emphasize that Trimble-RTX is a Web-based processing service for GNSS data (GPS, GLONASS, BeiDou, and QZSS) and operates an own global network of approximately 100 stations around the world for this purpose. For station with vastly (KC01) prevention of satellite signals, the best solutions were provided by APPS and CSRS-PPP using PPP approach among the Web-based services. Here, Trimble-RTX could not produce any solution. These results could demonstrate the benefit of multi-constellation of GNSS in the areas with limited satellite visibility because of increasing of the number of measurements. Comparación de precisión del método de Posicionamiento Preciso frente al posicionamiento relativo a través de diferentes productos de efemérides satelitales cerca y bajo un ambiente boscosoResumenEn los años recientes, debido al incremento de operadores satelitales de corrección de órbita y tiempo para la evaluación de información en tiempo real y de postproceso, se ha generalizado el método de posicionamiento preciso (PPP, del inglés Precise Point Positioning) que utiliza medidas del Sistema Global de Navegación por Satélite (GNSS, del inglés Global Navigation Satellite System) y servicios web de posicionamiento en línea. Debido a ventajas como el tiempo de ejecución y la relación costo-efectividad, muchos de los usuarios han implementado el método PPP en varias aplicaciones antes que el método tradicional de posicionamiento relativo. En las aplicaciones GNSS, la calidad de los productos de efemérides satelitales utilizados para la evaluación de información es un factor significante que afecta los resultados en las soluciones postproceso sea con la aplicación de métodos relativos o PPP en los análisis. Estos productos, clasificados como ultrarrápidos, rápidos y de órbita final, los proveen a los usuarios diferentes organizaciones nacionales e internacionales. En este artículo se estudia la exactitud del método PPP en comparación con los resultados de varios servicios web que utilizan diferentes productos de software y de efemérides satelitales. Con este objetivo se establecieron tres puntos de evaluación: el primero en un lugar con completa visibilidad satelital (AC01) y los otros dos con parcial (YC01) y reducida (KC01) señal satelital, en los alrededores y al interior de una zona boscosa del campus de Davutpaşa , en la Universidad Técnica Yildiz de Estambul. En las estaciones se llevaron a cabo observaciones estáticas con intervalos de seis horas el 4 de mayo de 2015. La información se recolectó con el programa Topcon HiperPro, un receptor de GPS y GLONASS (sistema GNSS desarrollado por la Unión Soviética), y se evaluó manualmente con el software científico Bernese v5.2 (BSW) y GIPSY-OASIS v6.3 (GIPSY). Además, la información también se procesón con seis servicios web en línea (AUSPOS, OPUS, CSRS-PPP, APPS, GAPS, Trimble-RTX) con productos de efemérides ultrarrápidas, rápidas y finales. Para la estación con completa visibilidad satelital (AC01), el análisis de los resultados indican una precisión coordinada de 1 cm en los procesamientos web y manual. Esto sugiere una buena calidad de las correcciones satelitales de órbita y tiempo usadas por los servicios de procesamiento de información en línea con el método PPP. Además, para la estación con señal parcial (YC01), las soluciones manuales tienen aproximadamente 1cm de coordinación en la precisión para los componentes Norte y Este. Luego, cuando se comparan los resultados entre los servicios web, los mejores resultados fueron de AUSPOS en soluciones relativas y Trimble RTX en el método PPP. Es importante recalcar que Trimble RTX es un servicio de procesamiento web para información GNSS (GPS, GLONASS, BeiDou y QZSS) y opera una red global propia de unas 100 estaciones en el mundo para este fin. Para la estación con una reducida señal satelital (KC01), las mejores soluciones fueron ofrecidas por APPS y CSRS-PPP con el método PPP entre los servicios web. En este caso, Trimble-RTX no puede producir ninguna solución. Estos resultados demuestran los beneficios de la multiconstelación GNSS en las áreas con visibilidad satelital limitada gracias al incremento del número de medidas.

The High Resolution Stereo Camera (HRSC) on the Mars Express orbiter (Neukum et al. 2004) is a multi-line pushbroom scanner that can obtain stereo and color coverage of targets in a single overpass, with pixel scales as small as 10 m at periapsis. Since commencing operations in 2004 it has imaged ~ 77 % of Mars at 20 m/pixel or better. The instrument team uses the Video Image Communication And Retrieval (VICAR) software to produce and archive a range of data products from uncalibrated and radiometrically calibrated images to controlled digital topographic models (DTMs) and orthoimages and regional mosaics of DTM and orthophoto data (Gwinner et al. 2009; 2010b; 2016). Alternatives to this highly effective standard processing pipeline are nevertheless of interest to researchers who do not have access to the full VICAR suite and may wish to make topographic products or perform other (e. g., spectrophotometric) analyses prior to the release of the highest level products. We have therefore developed software to ingest HRSC images and model their geometry in the USGS Integrated Software for Imagers and Spectrometers (ISIS3), which can be used for data preparation, geodetic control, and analysis, and the commercial photogrammetric software SOCET SET (® BAE Systems; Miller and Walker 1993; 1995) which can be used for independent production of DTMs and orthoimages. <br><br> The initial implementation of this capability utilized the then-current ISIS2 system and the generic pushbroom sensor model of SOCET SET, and was described in the DTM comparison of independent photogrammetric processing by different elements of the HRSC team (Heipke et al. 2007). A major drawback of this prototype was that neither software system then allowed for pushbroom images in which the exposure time changes from line to line. Except at periapsis, HRSC makes such timing changes every few hundred lines to accommodate changes of altitude and velocity in its elliptical orbit. As a result, it was necessary to split observations into blocks of constant exposure time, greatly increasing the effort needed to control the images and collect DTMs. <br><br> Here, we describe a substantially improved HRSC processing capability that incorporates sensor models with varying line timing in the current ISIS3 system (Sides 2017) and SOCET SET. This enormously reduces the work effort for processing most images and eliminates the artifacts that arose from segmenting them. In addition, the software takes advantage of the continuously evolving capabilities of ISIS3 and the improved image matching module NGATE (Next Generation Automatic Terrain Extraction, incorporating area and feature based algorithms, multi-image and multi-direction matching) of SOCET SET, thus greatly reducing the need for manual editing of DTM errors. We have also developed a procedure for geodetically controlling the images to Mars Orbiter Laser Altimeter (MOLA) data by registering a preliminary stereo topographic model to MOLA by using the point cloud alignment (<i>pc_align</i>) function of the NASA Ames Stereo Pipeline (ASP; Moratto et al. 2010). This effectively converts inter-image tiepoints into ground control points in the MOLA coordinate system. The result is improved absolute accuracy and a significant reduction in work effort relative to manual measurement of ground control. <i>The ISIS and ASP software used are freely available; SOCET SET, is a commercial product.</i> By the end of 2017 we expect to have ported our SOCET SET HRSC sensor model to the Community Sensor Model (CSM; Community Sensor Model Working Group 2010; Hare and Kirk 2017) standard utilized by the successor photogrammetric system SOCET GXP that is currently offered by BAE. In early 2018, we are also working with BAE to release the CSM source code under a BSD or MIT open source license. <br><br> We illustrate current HRSC processing capabilities with three examples, of which the first two come from the DTM comparison of 2007. Candor Chasma (h1235_0001) was a near-periapse observation with constant exposure time that could be processed relatively easily at that time. We show qualitative and quantitative improvements in DTM resolution and precision as well as greatly reduced need for manual editing, and illustrate some of the photometric applications possible in ISIS. At the Nanedi Valles site we are now able to process all 3 long-arc orbits (h0894_0000, h0905_0000 and h0927_0000) without segmenting the images. Finally, processing image set h4235_0001, which covers the landing site of the Mars Science Laboratory (MSL) rover and its rugged science target of Aeolus Mons in Gale crater, provides a rare opportunity to evaluate DTM resolution and precision because extensive High Resolution Imaging Science Experiment (HiRISE) DTMs are available (Golombek et al. 2012). The HiRISE products have ~ 50x smaller pixel scale so that discrepancies can mostly be attributed to HRSC. We use the HiRISE DTMs to compare the resolution and precision of our HRSC DTMs with the (evolving) standard products. <br><br> We find that the vertical precision of HRSC DTMs is comparable to the pixel scale but the horizontal resolution may be 15–30 image pixels, depending on processing. This is significantly coarser than the lower limit of 3–5 pixels based on the minimum size for image patches to be matched. Stereo DTMs registered to MOLA altimetry by surface fitting typically deviate by 10thinsp;m or less in mean elevation. Estimates of the RMS deviation are strongly influenced by the sparse sampling of the altimetry, but range from <thinsp;50thinsp;m in flat areas to ~ 100thinsp;m in rugged areas.

Recently, the newspapers and journals were bubbling with articles and editions devoted to various kinds of millennium and Y2K perspective. Some were retrospective and others prospective; some simply comprised lists of ‘greatests’. Interpreting the past with accuracy and insight is challenging, as is predicting the future. Fortunately, many others have already done that. So, instead, I will look at our discipline, cell biology, defined very broadly and to include molecular biology, both prospectively and retrospectively in the context of some perhaps prosaic but pertinent questions about the discipline that are surfacing as the centuries change. Many greats: One approach to summarizing the past is through lists of the greatest participants or classic papers in a given area. These lists appear frequently in areas like physics and mathematics, where progress is, or at least was, heavily influenced by heroic individuals who opened or sustained a field. In these areas, most participants and observers would develop a very similar list of the ‘greatests’, and nearly everyone working in the discipline would know what their contribution was. Is this true in cell biology? Are there names that everyone would know, or a canon of papers that everyone has read? Did the cell biology of the last 50–100 years evolve because of heroic individuals? Or were there only some insightful pioneers, followed by a large number of important accomplishments that occurred in many different laboratories? Interestingly, none of the major journals has compiled a ‘greatest’ list or even a “classic papers” list in cell biology. This is revealing. Perhaps it tells us that there were no great cell biologists - i.e. that the recent, great progress that we have witnessed didn't require great individuals. More likely, however, there are too many - that is, the advances in cell biology tend to be incremental, with many more bright sparks and contained blazes than forest fires. Seminal observations are frequent and arise in unexpected places. Progress may be better measured as the integral of many important contributions and contributors. Thus, cell biology is the product of many many great scientists, who interact, synergize and stand on each other's shoulders. The attractiveness of cell biology lies in this open, frontier culture. And the result is that the pie of success is large and that many have been rewarded. An interesting consequence of our frontier culture is that it is too exciting and fast paced for anyone to take the time to develop a sense of history and accomplishment. Sidney Brenner makes this point in his review of a book entitled ‘The lac Operon: A short history of a genetic paradigm’, by Benno Muller-Hill (Nature 386, 235). Brenner writes: “This book opens with the lament that for young molecular biologists history does not exist, and that they have no interest in the long struggle that has made the subject what it is today. I hold the weaker view that history does exist for the young, but it is divided into two epochs: the past two years, and everything that went before. That these have equal weight is a reflection of the exponential growth of the subject, and the urgent need to possess the future and acquire it more rapidly than anybody else does not make for empathy with the past.” A few years ago I read a list of the names of biomedical Nobel Laureates to some colleagues. They knew only a handful of the names and what their contributions were. It seems that so much is being accomplished so quickly it is hard for individuals to stand out. And the consequent focus on the collective achievement is what makes our discipline so rewarding for so many. But how long will this frontier culture last? The emergence of big biology, through government and private-foundation initiative, is changing the landscape. The rate of progress continues to accelerate. Will one soon require a very big lab to survive? Will creative minds find cell biology fertile territory? There are answers to big science. Most important is to embrace what it produces and look ahead. Another is to develop multi-institutional collaborative networks in which the product can far exceed the contributions of single individuals. And, finally, there are always trails to blaze and syntheses to make. They require little more than hard work, organization, good sense, perseverance, and some luck. Is it almost over? Extrapolating the rapid progress that we are witnessing, can one realistically predict what our discipline will be like over the next few decades? Will the questions that we are investigating now be answered or passe, and, if so, how soon? How long will cell biology continue to be on the center stage? Will there be new, fundamental, concepts or a paradigm shift? What ‘unexpecteds’ might we expect? At meetings over beer and at dinner tables with seminar speakers, the question “Is it almost over?” creeps in with increasing frequency. The concern is that the big picture will be in place soon - that is, the outlines of the fundamental cellular processes will be largely understood at a molecular level. This concern, of course, reflects the depth with which one wants to understand the cell. Clearly, we now know vastly more than we did even a decade ago. There is an emerging sense that a rudimentary understanding of the most basic cellular processes is in sight; one sees this even in the undergraduate cell biology textbooks. Of course, progress will continue. However, the questions about fundamental processes will become increasingly refined, and the answers more detailed - more likely to occupy space in specialty treatises than in undergraduate cell biology texts. The approaches and concepts will become more deeply linked to chemistry and physics, eventually focusing on subtleties of mechanism and structure. Some of these details will change our basic concepts dramatically; but the frequency of such occurrences will dwindle. These details are also necessary for the applications of cell biology that are beginning to emerge and for a true marriage of cell biology with the molecular world. This level of inquiry and detail, or increasing reductionism, may not sustain the interest of or resonate well with many of our colleagues. However, for others, it's just the beginning and is opening doors for a cadre of new colleagues trained in physics and chemistry to enter with fresh ideas, insights and technologies. Will it ever end? But is it almost over? Do we really know how cells do what they do? How is the thicket of seemingly redundant pathways and networks, molecules, and supramolecular assemblies coordinated spatially and temporally? Which of the many pathways and redundant mechanisms revealed in culture are utilized in vivo. How are cellular phenomena, as revealed in the spatial and temporal coordination required for cell division or migration, for example, integrated? How do groups of cells integrate and coordinate to effect tissue function, embryonic development, and pathology, for example? As we begin to observe cellular phenomena in situ, they can appear very different from those observed in culture. The compensation and redundancy seen in knockout, transgenic or mutated organisms also reveals a diversity of possible mechanisms. It seems that the cell has different ways of doing the same thing. How does the cell do it normally, and when, if ever, are the other mechanisms used? We have tended to focus the majority of our efforts on a few cell types. What about the other cells? How do they do it? These questions are especially pertinent in developmental biology and pathobiology, where the cellular environments are changing; they also point to a class of challenging, important new avenue of investigation. As the canon of cellular phenomena becomes understood at an increasingly refined level, it provides the basis for explaining integrative phenomena. It also becomes the source of interesting and important practical applications. In this way, cell biology can become the language for understanding complex integrative phenomena like learning and memory, behavior and personality - areas in which the genome project and genetics might merge to provide unique insights. In addition, cell biology is the source of endless practical applications and, in some sense, sits in the center of a booming biotechnology industry that includes novel therapeutic strategies, designer animals and plants, tissue replacements, biomaterials and biosensors. The possibilities here seem endless. What does genomics bode for cell biology? A great deal of opportunity. Do sequences, homologies, binding interactions, changes in expression, and even knockouts provide a satisfactory understanding of function? Isn't the genomic bottleneck the assignment of cellular functions to different genes? In its essence, gene function can be viewed as a cell biological issue and perhaps not fully amenable to high-throughput analysis. Thus, the genome project promises to keep cell biology on the center stage. And maybe, therefore, we will have too much to do. The devil is in the detail: A major product of the successes in cell biology is a mind-numbing number of facts, particulars, data and details. The volume of information and detail that we are generating in genome studies and cell signaling, for example, unsettles some. Will the molecular paradigm, which has been so successful and brought us here, lead us to the next level? In the reductionist paradigm, the cell can be viewed as a complex chemical system that obeys the laws of physics and the principles of chemistry. In this view, one needs to know the relevant chemical properties for all of the cellular components. Once this is known, the cellular dynamics and equilibria can be computed, and ultimately cell behavior modeled. For small systems and isolated processes, this has had an important predictive value and has been insightful and revealing. Most importantly, it uses the principles of chemistry, which is a common language that is known and understood by nearly all participants. Can this approach be usefully extrapolated to a highly complex system like an entire cell? It may take a while, as it poses some interesting challenges. How many complex differential equations, which must cover both temporal and spatial distributions, would be involved? How accurately will the concentrations and rate constants need to be measured? How does one deal with the non-ideal nature of the cell interior and exterior? The differential equations required to describe the systems of interacting pathways or networks found in a cell will necessarily be very complex and contain many terms. How does the error in measurements of the rate constants and concentrations, for example, propagate - that is, given any reasonable measurement error, can one derive anything that is meaningful and useful? The situation is complicated further by the nature of the cell. What are the effective concentrations (the activities) of the components? How does one address reactions that are occurring on surfaces or macromolecular assemblies that can be dynamic? These are formidable challenges. Chemistry faces them continually, as do other sciences that deal with complex phenomena. Natural phenomena have strong roots in the principles of physics and the concepts of chemistry. Yet the mathematics that backs them up does not readily yield to highly complex phenomena. Maybe different approaches - perhaps one based in the complex-systems theory that is so familiar to engineers - will provide an alternative. Where's the big picture? Are there other ways of dealing with our flood of details and particulars? There is a call for mathematicians, computer scientists, engineers and/or theorists to help bring order to this information flood. Can they make sense of this complexity? Are there overarching and unifying concepts that will allow us to think in generalities, rather than in particulars? There may already be some unifying concepts. One is the genetic paradigm, which views a cell's behavior as a consequence of its expressed genes. The geneticist's point of view has already provided an important, empirical and quantitative way of looking at cellular and organismal phenomena. This view of a cell or organism, or even a disease like cancer, differs greatly from that of a biochemist, which focuses on mechanisms and specifics. In some respects, it shifts attention away from the particulars and sticky mechanistic issues, and thus can be simplifying. Genetics has been a very powerful driver in many areas, not only as a tool to determine function but also as a way of looking at a process. The marriage of genetics with developmental biology is only one of many examples. A number of other examples derive from modeling. The Hodgkin-Huxley equation is one prominent and useful example. It models the axon as an electrical entity. For other purposes, the cell has been likewise treated as a mechanical entity and modeled in the jargon of mechanics. There are other ways of modeling the cell and its component processes - for example, through signal and systems theory, network and graph theory, Boolean algebra, and statistics. Each of these treatments can be meaningful and useful to those well versed in that particular discipline. But are these useful to those not versed in them? Is there a unifying theory or model that avoids a proliferation of models. How does one connect them to our chemical roots? In physics, the simplest is accepted as correct. Cell biology has a different reality. It is derived evolutionarily, and therefore, the simplest model may not be correct or even useful. Perhaps, in the future, there will even be a synthesis - like the periodic table or quantum mechanics for physics and chemistry - that allows us to deal with the mega-detail that we are generating. Big surprises in small packages: To date, cell biology has progressed rapidly because of its qualitative nature. Differences in localization are often characterized by fluorescence intensities that are described qualitatively as brighter or dimmer or as more or less localized. Similarly, differences in expression are often characterized by the intensity of bands on western blots or SDS gels; these are often described as bigger or smaller. Many changes are, in fact, very large, and this level of characterization is likely to be adequate. But have we missed anything? Is there a need for more quantitative measurements? When differences in expression are analyzed by gene array, where does one draw the line? Is a tenfold change more significant than a 2–3-fold change? Many measurements would not detect changes that are only 2–3-fold, and in others we have tended to ignore them. We wouldn't see such a small change in fluorescence intensity by eye, for example, nor would we readily identify changes in concentration that arise from differences in localization rather than expression. Ignoring small changes assumes that biological readouts are not highly poised. But is this true? Systems that have interacting components, undergo conformational changes or enzymatic modifications, or are part of amplifying cascades, for example, can be highly poised. Thus 2–3-fold changes in expression or in substrate/ligand concentration can have effects that are very large. Of course, the converse follows as well. Large changes might have only modest consequences - for example, if one is well removed from the Kd. Examples of small changes having large effects and vice versa are common features of complex systems and are now beginning to appear in the cell biology literature. It seems likely there will be many more as our measurements become increasingly quantitative. Downstream signals: What can one make of all of this? (1) This is a very, very good time for cell biology. Questions that have loomed for decades and centuries are becoming understood in a meaningful way. The progress is breathtaking; it wasn't this easy only a couple of decades ago. (2) Many are participating in the success; they are all contributing to something useful and important. (3) The devil is in the detail but so are the opportunities. (4) Big science is here to stay - perhaps a consequence of our success. As investigators, we need to embrace it and look ahead. (5) The only constant in our research will be change. We will need to be flexible in our approaches and questions. (6) We must translate our progress to the public through education and the popular press in ways that sustain their interest and support and attract new minds to our discipline. (7) The surge in new technology will continue to drive our progress, which will come to nearly anyone who works hard, chooses a good problem, and takes a reasonable approach. (8) We need to develop strategies to deal with the information flood; it won't ebb soon. And the anticipated simplifications from the mathematicians, computer scientists and modelers may take quite a while. (9) Enjoy your successes. This might be about as good as it gets.

Environments containing significant concentration of NaCl such as salt lakes harbor extremophiles microorganisms which have a great biotechnology interest. To explore the diversity of Bacteria in Chott Tinsilt (Algeria), an isolation program was performed. Water samples were collected from the saltern during the pre-salt harvesting phase. This Chott is high in salt (22.47% (w/v). Seven halophiles Bacteria were selected for further characterization. The isolated strains were able to grow optimally in media with 10–25% (w/v) total salts. Molecular identification of the isolates was performed by sequencing the 16S rRNA gene. It showed that these cultured isolates included members belonging to the Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus genera with less than 98% of similarity with their closest phylogenetic relative. The halophilic bacterial isolates were also characterized for the production of biosurfactant and industrially important enzymes. Most isolates produced hydrolases and biosurfactants at high salt concentration. In fact, this is the first report on bacterial strains (A4 and B4) which were a good biosurfactant and coagulase producer at 20% and 25% ((w/v)) NaCl. In addition, the biosurfactant produced by the strain B4 at high salinity (25%) was also stable at high temperature (30-100°C) and high alkalinity (pH 11).Key word: Salt Lake, Bacteria, biosurfactant, Chott, halophiles, hydrolases, 16S rRNAINTRODUCTIONSaline lakes cover approximately 10% of the Earth’s surface area. The microbial populations of many hypersaline environments have already been studied in different geographical regions such as Great Salt Lake (USA), Dead Sea (Israel), Wadi Natrun Lake (Egypt), Lake Magadi (Kenya), Soda Lake (Antarctica) and Big Soda Lake and Mono Lake (California). Hypersaline regions differ from each other in terms of geographical location, salt concentration and chemical composition, which determine the nature of inhabitant microorganisms (Gupta et al., 2015). Then low taxonomic diversity is common to all these saline environments (Oren et al., 1993). Halophiles are found in nearly all major microbial clades, including prokaryotic (Bacteria and Archaea) and eukaryotic forms (DasSarma and Arora, 2001). They are classified as slight halophiles when they grow optimally at 0.2–0.85 M (2–5%) NaCl, as moderate halophiles when they grow at 0.85–3.4 M (5–20%) NaCl, and as extreme halophiles when they grow at 3.4–5.1 M (20–30%) NaCl. Hyper saline environments are inhabited by extremely halophilic and halotolerant microorganisms such as Halobacillus sp, Halobacterium sp., Haloarcula sp., Salinibacter ruber , Haloferax sp and Bacillus spp. (Solomon and Viswalingam, 2013). There is a tremendous demand for halophilic bacteria due to their biotechnological importance as sources of halophilic enzymes. Enzymes derived from halophiles are endowed with unique structural features and catalytic power to sustain the metabolic and physiological processes under high salt conditions. Some of these enzymes have been reported to be active and stable under more than one extreme condition (Karan and Khare, 2010). Applications are being considered in a range of industries such as food processing, washing, biosynthetic processes and environmental bioremediation. Halophilic proteases are widely used in the detergent and food industries (DasSarma and Arora, 2001). However, esterases and lipases have also been useful in laundry detergents for the removal of oil stains and are widely used as biocatalysts because of their ability to produce pure compounds. Likewise, amylases are used industrially in the first step of the production of high fructose corn syrup (hydrolysis of corn starch). They are also used in the textile industry in the de-sizing process and added to laundry detergents. Furthermore, for the environmental applications, the use of halophiles for bioremediation and biodegradation of various materials from industrial effluents to soil contaminants and accidental spills are being widely explored. In addition to enzymes, halophilic / halotolerants microorganisms living in saline environments, offer another potential applications in various fields of biotechnology like the production of biosurfactant. Biosurfactants are amphiphilic compounds synthesized from plants and microorganisms. They reduce surface tension and interfacial tension between individual molecules at the surface and interface respectively (Akbari et al., 2018). Comparing to the chemical surfactant, biosurfactant are promising alternative molecules due to their low toxicity, high biodegradability, environmental capability, mild production conditions, lower critical micelle concentration, higher selectivity, availability of resources and ability to function in wide ranges of pH, temperature and salinity (Rocha et al., 1992). They are used in various industries which include pharmaceuticals, petroleum, food, detergents, cosmetics, paints, paper products and water treatment (Akbari et al., 2018). The search for biosurfactants in extremophiles is particularly promising since these biomolecules can adapt and be stable in the harsh environments in which they are to be applied in biotechnology.OBJECTIVESEastern Algeria features numerous ecosystems including hypersaline environments, which are an important source of salt for food. The microbial diversity in Chott Tinsilt, a shallow Salt Lake with more than 200g/L salt concentration and a superficies of 2.154 Ha, has never yet been studied. The purpose of this research was to chemically analyse water samples collected from the Chott, isolate novel extremely or moderate halophilic Bacteria, and examine their phenotypic and phylogenetic characteristics with a view to screening for biosurfactants and enzymes of industrial interest.MATERIALS AND METHODSStudy area: The area is at 5 km of the Commune of Souk-Naâmane and 17 km in the South of the town of Aïn-Melila. This area skirts the trunk road 3 serving Constantine and Batna and the railway Constantine-Biskra. It is part the administrative jurisdiction of the Wilaya of Oum El Bouaghi. The Chott belongs to the wetlands of the High Plains of Constantine with a depth varying rather regularly without never exceeding 0.5 meter. Its length extends on 4 km with a width of 2.5 km (figure 1).Water samples and physico-chemical analysis: In February 2013, water samples were collected from various places at the Chott Tinsilt using Global Positioning System (GPS) coordinates of 35°53’14” N lat. and 06°28’44”E long. Samples were collected randomly in sterile polythene bags and transported immediately to the laboratory for isolation of halophilic microorganisms. All samples were treated within 24 h after collection. Temperature, pH and salinity were measured in situ using a multi-parameter probe (Hanna Instruments, Smithfield, RI, USA). The analytical methods used in this study to measure ions concentration (Ca2+, Mg2+, Fe2+, Na+, K+, Cl−, HCO3−, SO42−) were based on 4500-S-2 F standard methods described elsewhere (Association et al., 1920).Isolation of halophilic bacteria from water sample: The media (M1) used in the present study contain (g/L): 2.0 g of KCl, 100.0/200.0 g of NaCl, 1.0 g of MgSO4.7HO2, 3.0 g of Sodium Citrate, 0.36 g of MnCl2, 10.0 g of yeast extract and 15.0 g agar. The pH was adjusted to 8.0. Different dilutions of water samples were added to the above medium and incubated at 30°C during 2–7 days or more depending on growth. Appearance and growth of halophilic bacteria were monitored regularly. The growth was diluted 10 times and plated on complete medium agar (g/L): glucose 10.0; peptone 5.0; yeast extract 5.0; KH2PO4 5.0; agar 30.0; and NaCl 100.0/200.0. Resultant colonies were purified by repeated streaking on complete media agar. The pure cultures were preserved in 20% glycerol vials and stored at −80°C for long-term preservation.Biochemical characterisation of halophilic bacterial isolates: Bacterial isolates were studied for Gram’s reaction, cell morphology and pigmentation. Enzymatic assays (catalase, oxidase, nitrate reductase and urease), and assays for fermentation of lactose and mannitol were done as described by Smibert (1994).Optimization of growth conditions: Temperature, pH, and salt concentration were optimized for the growth of halophilic bacterial isolates. These growth parameters were studied quantitatively by growing the bacterial isolates in M1 medium with shaking at 200 rpm and measuring the cell density at 600 nm after 8 days of incubation. To study the effect of NaCl on the growth, bacterial isolates were inoculated on M1 medium supplemented with different concentration of NaCl: 1%-35% (w/v). The effect of pH on the growth of halophilic bacterial strains was studied by inoculating isolates on above described growth media containing NaCl and adjusted to acidic pH of 5 and 6 by using 1N HCl and alkaline pH of 8, 9, 10, 11 and 12 using 5N NaOH. The effect of temperature was studied by culturing the bacterial isolates in M1 medium at different temperatures of incubation (4°C–55°C).Screening of halophilic bacteria for hydrolytic enzymes: Hydrolase producing bacteria among the isolates were screened by plate assay on starch, tributyrin, gelatin and DNA agar plates respectively for amylase, lipase, protease and DNAse activities. Amylolytic activity of the cultures was screened on starch nutrient agar plates containing g/L: starch 10.0; peptone 5.0; yeast extract 3.0; agar 30.0; NaCl 100.0/250.0. The pH was 7.0. After incubation at 30 ºC for 7 days, the zone of clearance was determined by flooding the plates with iodine solution. The potential amylase producers were selected based on ratio of zone of clearance diameter to colony diameter. Lipase activity of the cultures was screened on tributyrin nutrient agar plates containing 1% (v/v) of tributyrin. Isolates that showed clear zones of tributyrin hydrolysis were identified as lipase producing bacteria. Proteolytic activity of the isolates was similarly screened on gelatin nutrient agar plates containing 10.0 g/L of gelatin. The isolates showing zones of gelatin clearance upon treatment with acidic mercuric chloride were selected and designated as protease producing bacteria. The presence of DNAse activity on plates was determined on DNAse test agar (BBL) containing 10%-25% (w/v) total salt. After incubation for 7days, the plates were flooded with 1N HCl solution. Clear halos around the colonies indicated DNAse activity (Jeffries et al., 1957).Milk clotting activity (coagulase activity) of the isolates was also determined following the procedure described (Berridge, 1952). Skim milk powder was reconstituted in 10 mM aqueous CaCl2 (pH 6.5) to a final concentration of 0.12 kg/L. Enzyme extracts were added at a rate of 0.1 mL per mL of milk. The coagulation point was determined by manual rotating of the test tube periodically, at short time intervals, and checking for visible clot formation.Screening of halophilic bacteria for biosurfactant production. Oil spread Assay: The Petridis base was filled with 50 mL of distilled water. On the water surface, 20μL of diesel and 10μl of culture were added respectively. The culture was introduced at different spots on the diesel, which is coated on the water surface. The occurrence of a clear zone was an indicator of positive result (Morikawa et al., 2000). The diameter of the oil expelling circles was measured by slide caliber (with a degree of accuracy of 0.02 mm).Surface tension and emulsification index (E24): Isolates were cultivated at 30 °C for 7 days on the enrichment medium containing 10-25% NaCl and diesel oil as the sole carbon source. The medium was centrifuged (7000 rpm for 20 min) and the surface tension of the cell-free culture broth was measured with a TS90000 surface tensiometer (Nima, Coventry, England) as a qualitative indicator of biosurfactant production. The culture broth was collected with a Pasteur pipette to remove the non-emulsified hydrocarbons. The emulsifying capacity was evaluated by an emulsification index (E24). The E24 of culture samples was determined by adding 2 mL of diesel oil to the same amount of culture, mixed for 2 min with a vortex, and allowed to stand for 24 h. E24 index is defined as the percentage of height of emulsified layer (mm) divided by the total height of the liquid column (mm).Biosurfactant stability studies : After growth on diesel oil as sole source of carbone, cultures supernatant obtained after centrifugation at 6,000 rpm for 15 min were considered as the source of crude biosurfactant. Its stability was determined by subjecting the culture supernatant to various temperature ranges (30, 40, 50, 60, 70, 80 and 100 °C) for 30 min then cooled to room temperature. Similarly, the effect of different pH (2–11) on the activity of the biosurfactant was tested. The activity of the biosurfactant was investigated by measuring the emulsification index (El-Sersy, 2012).Molecular identification of potential strains. DNA extraction and PCR amplification of 16S rDNA: Total cellular DNA was extracted from strains and purified as described by Sambrook et al. (1989). DNA was purified using Geneclean® Turbo (Q-BIO gene, Carlsbad, CA, USA) before use as a template in polymerase chain reaction (PCR) amplification. For the 16S rDNA gene sequence, the purified DNA was amplified using a universal primer set, forward primer (27f; 5′-AGA GTT TGA TCM TGG CTC AG) and a reverse primer (1492r; 5′-TAC GGY TAC CTT GTT ACG ACT T) (Lane, 1991). Agarose gel electrophoresis confirmed the amplification product as a 1400-bp DNA fragment.16S rDNA sequencing and Phylogenic analysis: Amplicons generated using primer pair 27f-1492r was sequenced using an automatic sequencer system at Macrogene Company (Seoul, Korea). The sequences were compared with those of the NCBI BLAST GenBank nucleotide sequence databases. Phylogenetic trees were constructed by the neighbor-joining method using MEGA version 5.05 software (Tamura et al., 2011). Bootstrap resembling analysis for 1,000 replicates was performed to estimate the confidence of tree topologies.Nucleotide sequence accession numbers: The nucleotide sequences reported in this work have been deposited in the EMBL Nucleotide Sequence Database. The accession numbers are represented in table 5.Statistics: All experiments were conducted in triplicates. Results were evaluated for statistical significance using ANOVA.RESULTSPhysico-chemical parameters of the collected water samples: The physicochemical properties of the collected water samples are reported in table 1. At the time of sampling, the temperature was 10.6°C and pH 7.89. The salinity of the sample, as determined in situ, was 224.70 g/L (22,47% (w/v)). Chemical analysis of water sample indicated that Na +and Cl- were the most abundant ions (table 1). SO4-2 and Mg+2 was present in much smaller amounts compared to Na +and Cl- concentration. Low levels of calcium, potassium and bicarbonate were also detected, often at less than 1 g/L.Characterization of isolates. Morphological and biochemical characteristic feature of halophilic bacterial isolates: Among 52 strains isolated from water of Chott Tinsilt, seven distinct bacteria (A1, A2, A3, A4, B1, B4 and B5) were chosen for further characterization (table 2). The colour of the isolates varied from beige, pale yellow, yellowish and orange. The bacterial isolates A1, A2, A4, B1 and B5 were rod shaped and gram negative (except B5), whereas A3 and B4 were cocci and gram positive. All strains were oxidase and catalase positive except for B1. Nitrate reductase and urease activities were observed in all the bacterial isolates, except B4. All the bacterial isolates were negative for H2S formation. B5 was the only strain positive for mannitol fermentation (table 2).We isolated halophilic bacteria on growth medium with NaCl supplementation at pH 7 and temperature of 30°C. We studied the effect of NaCl, temperature and pH on the growth of bacterial isolates. All the isolates exhibited growth only in the presence of NaCl indicating that these strains are halophilic. The optimum growth of isolates A3 and B1 was observed in the presence of 10% NaCl, whereas it was 15% NaCl for A1, A2 and B5. A4 and B4 showed optimum growth in the presence of 20% and 25% NaCl respectively. A4, B4 and B5 strains can tolerate up to 35% NaCl.The isolate B1 showed growth in medium supplemented with 10% NaCl and pH range of 7–10. The optimum pH for the growth B1 was 9 and they did not show any detectable growth at or below pH 6 (table 2), which indicates the alkaliphilic nature of B1 isolate. The bacterial isolates A1, A2 and A4 exhibited growth in the range of pH 6–10, while A3 and B4 did not show any growth at pH greater than 8. The optimum pH for growth of all strains (except B1) was pH 7.0 (table 2). These results indicate that A1, A2, A3, A4, B4 and B5 are neutrophilic in nature. All the bacterial isolates exhibited optimal growth at 30°C and no detectable growth at 55°C. Also, detectable growth of isolates A1, A2 and A4 was observed at 4°C. However, none of the bacterial strains could grow below 4°C and above 50°C (table 2).Screening of the halophilic enzymes: To characterize the diversity of halophiles able to produce hydrolytic enzymes among the population of microorganisms inhabiting the hypersaline habitats of East Algeria (Chott Tinsilt), a screening was performed. As described in Materials and Methods, samples were plated on solid media containing 10%-25% (w/v) of total salts and different substrates for the detection of amylase, protease, lipase and DNAse activities. However, coagulase activity was determined in liquid medium using milk as substrate (figure 3). Distributions of hydrolytic activity among the isolates are summarized in table 4.From the seven bacterial isolates, four strains A1, A2, A4 and B5 showed combined hydrolytic activities. They were positive for gelatinase, lipase and coagulase. A3 strain showed gelatinase and lipase activities. DNAse activities were detected with A1, A4, B1 and B5 isolates. B4 presented lipase and coagulase activity. Surprisingly, no amylase activity was detected among all the isolates.Screening for biosurfactant producing isolates: Oil spread assay: The results showed that all the strains could produce notable (>4 cm diameter) oil expelling circles (ranging from 4.11 cm to 4.67 cm). The average diameter for strain B5 was 4.67 cm, significantly (P < 0.05) higher than for the other strains.Surface tension and emulsification index (E24): The assimilation of hydrocarbons as the sole sources of carbon by the isolate strains led to the production of biosurfactants indicated by the emulsification index and the lowering of the surface tension of cell-free supernatant. Based on rapid growth on media containing diesel oil as sole carbon source, the seven isolates were tested for biosurfactant production and emulsification activity. The obtained values of the surface tension measurements as well as the emulsification index (E24) are shown in table 3. The highest reduction of surface tension was achieved with B5 and A3 isolates with values of 25.3 mN m−1 and 28.1 mN m−1 respectively. The emulsifying capacity evaluated by the E24 emulsification index was highest in the culture of isolate B4 (78%), B5 (77%) and A3 (76%) as shown in table 3 and figure 2. These emulsions were stable even after 4 months. The bacteria with emulsification indices higher than 50 % and/or reduction in the surface tension (under 30 mN/m) have been defined as potential biosurfactant producers. Based on surface tension and the E24 index results, isolates B5, B4, A3 and A4 are the best candidates for biosurfactant production. It is important to note that, strains B4 and A4 produce biosurfactant in medium containing respectively 25% and 20% (w/v) NaCl.Stability of biosurfactant activities: The applicability of biosurfactants in several biotechnological fields depends on their stability at different environmental conditions (temperatures, pH and NaCl). For this study, the strain B4 appear very interesting (It can produce biosurfactant at 25 % NaCl) and was choosen for futher analysis for biosurfactant stability. The effects of temperature and pH on the biosurfactant production by the strain B4 are shown in figure 4.biosurfactant in medium containing respectively 25% and 20% (w/v) NaCl.Stability of biosurfactant activities: The applicability of biosurfactants in several biotechnological fields depends on their stability at different environmental conditions (temperatures, pH and NaCl). For this study, the strain B4 appear very interesting (It can produce biosurfactant at 25 % NaCl) and was chosen for further analysis for biosurfactant stability. The effects of temperature and pH on the biosurfactant production by the strain B4 are shown in figure 4. The biosurfactant produced by this strain was shown to be thermostable giving an E-24 Index value greater than 78% (figure 4A). Heating of the biosurfactant to 100 °C caused no significant effect on the biosurfactant performance. Therefore, the surface activity of the crude biosurfactant supernatant remained relatively stable to pH changes between pH 6 and 11. At pH 11, the value of E24 showed almost 76% activity, whereas below pH 6 the activity was decreased up to 40% (figure 4A). The decreases of the emulsification activity by decreasing the pH value from basic to an acidic region; may be due to partial precipitation of the biosurfactant. This result indicated that biosurfactant produced by strain B4 show higher stability at alkaline than in acidic conditions.Molecular identification and phylogenies of potential isolates: To identify halophilic bacterial isolates, the 16S rDNA gene was amplified using gene-specific primers. A PCR product of ≈ 1.3 kb was detected in all the seven isolates. The 16S rDNA amplicons of each bacterial isolate was sequenced on both strands using 27F and 1492R primers. The complete nucleotide sequence of 1336,1374, 1377,1313, 1305,1308 and 1273 bp sequences were obtained from A1, A2, A3, A4, B1, B4 and B5 isolates respectively, and subjected to BLAST analysis. The 16S rDNA sequence analysis showed that the isolated strains belong to the genera Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus as shown in table 5. The halophilic isolates A2 and A4 showed 97% similarity with the Halomonas variabilis strain GSP3 (accession no. AY505527) and the Halomonas sp. M59 (accession no. AM229319), respectively. As for A1, it showed 96% similarity with the Halomonas venusta strain GSP24 (accession no. AY553074). B1 and B4 showed for their part 96% similarity with the Salinivibrio costicola subsp. alcaliphilus strain 18AG DSM4743 (accession no. NR_042255) and the Planococcus citreus (accession no. JX122551), respectively. The bacterial isolate B5 showed 98% sequence similarity with the Halobacillus trueperi (accession no. HG931926), As for A3, it showed only 95% similarity with the Staphylococcus arlettae (accession no. KR047785). The 16S rDNA nucleotide sequences of all the seven halophilic bacterial strains have been submitted to the NCBI GenBank database under the accession number presented in table 5. The phylogenetic association of the isolates is shown in figure 5.DICUSSIONThe physicochemical properties of the collected water samples indicated that this water was relatively neutral (pH 7.89) similar to the Dead Sea and the Great Salt Lake (USA) and in contrast to the more basic lakes such as Lake Wadi Natrun (Egypt) (pH 11) and El Golea Salt Lake (Algeria) (pH 9). The salinity of the sample was 224.70 g/L (22,47% (w/v). This range of salinity (20-30%) for Chott Tinsilt is comparable to a number of well characterized hypersaline ecosystems including both natural and man-made habitats, such as the Great Salt Lake (USA) and solar salterns of Puerto Rico. Thus, Chott Tinsilt is a hypersaline environment, i.e. environments with salt concentrations well above that of seawater. Chemical analysis of water sample indicated that Na +and Cl- were the most abundant ions, as in most hypersaline ecosystems (with some exceptions such as the Dead Sea). These chemical water characteristics were consistent with the previously reported data in other hypersaline ecosystems (DasSarma and Arora, 2001; Oren, 2002; Hacěne et al., 2004). Among 52 strains isolated from this Chott, seven distinct bacteria (A1, A2, A3, A4, B1, B4 and B5) were chosen for phenotypique, genotypique and phylogenetique characterization.The 16S rDNA sequence analysis showed that the isolated strains belong to the genera Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus. Genera obtained in the present study are commonly occurring in various saline habitats across the globe. Staphylococci have the ability to grow in a wide range of salt concentrations (Graham and Wilkinson, 1992; Morikawa et al., 2009; Roohi et al., 2014). For example, in Pakistan, Staphylococcus strains were isolated from various salt samples during the study conducted by Roohi et al. (2014) and these results agreed with previous reports. Halomonas, halophilic and/or halotolerant Gram-negative bacteria are typically found in saline environments (Kim et al., 2013). The presence of Planococcus and Halobacillus has been reported in studies about hypersaline lakes; like La Sal del Rey (USA) (Phillips et al., 2012) and Great Salt Lake (Spring et al., 1996), respectively. The Salinivibrio costicola was a representative model for studies on osmoregulatory and other physiological mechanisms of moderately halophilic bacteria (Oren, 2006).However, it is interesting to note that all strains shared less than 98.7% identity (the usual species cut-off proposed by Yarza et al. (2014) with their closest phylogenetic relative, suggesting that they could be considered as new species. Phenotypic, genetic and phylogenetic analyses have been suggested for the complete identification of these strains. Theses bacterial strains were tested for the production of industrially important enzymes (Amylase, protease, lipase, DNAse and coagulase). These isolates are good candidates as sources of novel enzymes with biotechnological potential as they can be used in different industrial processes at high salt concentration (up to 25% NaCl for B4). Prominent amylase, lipase, protease and DNAase activities have been reported from different hypersaline environments across the globe; e.g., Spain (Sánchez‐Porro et al., 2003), Iran (Rohban et al., 2009), Tunisia (Baati et al., 2010) and India (Gupta et al., 2016). However, to the best of our knowledge, the coagulase activity has never been detected in extreme halophilic bacteria. Isolation and characterization of crude enzymes (especially coagulase) to investigate their properties and stability are in progress.The finding of novel enzymes with optimal activities at various ranges of salt concentrations is of great importance. Besides being intrinsically stable and active at high salt concentrations, halophilic and halotolerant enzymes offer great opportunities in biotechnological applications, such as environmental bioremediation (marine, oilfiel) and food processing. The bacterial isolates were also characterized for production of biosurfactants by oil-spread assay, measurement of surface tension and emulsification index (E24). There are few reports on biosurfactant producers in hypersaline environments and in recent years, there has been a greater increase in interest and importance in halophilic bacteria for biomolecules (Donio et al., 2013; Sarafin et al., 2014). Halophiles, which have a unique lipid composition, may have an important role to play as surface-active agents. The archae bacterial ether-linked phytanyl membrane lipid of the extremely halophilic bacteria has been shown to have surfactant properties (Post and Collins, 1982). Yakimov et al. (1995) reported the production of biosurfactant by a halotolerant Bacillus licheniformis strain BAS 50 which was able to produce a lipopeptide surfactant when cultured at salinities up to 13% NaCl. From solar salt, Halomonas sp. BS4 and Kocuria marina BS-15 were found to be able to produce biosurfactant when cultured at salinities of 8% and 10% NaCl respectively (Donio et al., 2013; Sarafin et al., 2014). In the present work, strains B4 and A4 produce biosurfactant in medium containing respectively 25% and 20% NaCl. To our knowledge, this is the first report on biosurfactant production by bacteria under such salt concentration. Biosurfactants have a wide variety of industrial and environmental applications (Akbari et al., 2018) but their applicability depends on their stability at different environmental conditions. The strain B4 which can produce biosurfactant at 25% NaCl showed good stability in alkaline pH and at a temperature range of 30°C-100°C. Due to the enormous utilization of biosurfactant in detergent manufacture the choice of alkaline biosurfactant is researched (Elazzazy et al., 2015). On the other hand, the interesting finding was the thermostability of the produced biosurfactant even after heat treatment (100°C for 30 min) which suggests the use of this biosurfactant in industries where heating is of a paramount importance (Khopade et al., 2012). To date, more attention has been focused on biosurfactant producing bacteria under extreme conditions for industrial and commercial usefulness. In fact, the biosurfactant produce by strain B4 have promising usefulness in pharmaceutical, cosmetics and food industries and for bioremediation in marine environment and Microbial enhanced oil recovery (MEOR) where the salinity, temperature and pH are high.CONCLUSIONThis is the first study on the culturable halophilic bacteria community inhabiting Chott Tinsilt in Eastern Algeria. Different genera of halotolerant bacteria with different phylogeneticaly characteristics have been isolated from this Chott. Culturing of bacteria and their molecular analysis provides an opportunity to have a wide range of cultured microorganisms from extreme habitats like hypersaline environments. Enzymes produced by halophilic bacteria show interesting properties like their ability to remain functional in extreme conditions, such as high temperatures, wide range of pH, and high salt concentrations. These enzymes have great economical potential in industrial, agricultural, chemical, pharmaceutical, and biotechnological applications. Thus, the halophiles isolated from Chott Tinsilt offer an important potential for application in microbial and enzyme biotechnology. In addition, these halo bacterial biosurfactants producers isolated from this Chott will help to develop more valuable eco-friendly products to the pharmacological and food industries and will be usefulness for bioremediation in marine environment and petroleum industry.ACKNOWLEDGMENTSOur thanks to Professor Abdelhamid Zoubir for proofreading the English composition of the present paper.CONFLICT OF INTERESTThe authors declare that they have no conflict of interest.Akbari, S., N. H. Abdurahman, R. M. Yunus, F. Fayaz and O. R. Alara, 2018. Biosurfactants—a new frontier for social and environmental safety: A mini review. Biotechnology research innovation, 2(1): 81-90.Association, A. P. H., A. W. W. Association, W. P. C. 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The promising approach to enhance energy efficiency (EE) in LTE-A network is to switch underutilized evolved node B (eNB) to sleep mode, but it increases the transmission power to guarantee the coverage under the remaining active eNBs. The increase in transmission power can be reduced by coordinated multi-point (CoMP) technique through eNB cooperation, but this technique consumes extra power due to backhaul traffic and signal processing. This problem can be solved by the proposed energy efficient acceleration factor failure rate (EEAFR) algorithm. The algorithm jointly considers the eNB cooperation and DTX mechanism to minimize the backhaul traffic with less failure rate. Also, to enhance energy efficiency, the proposed algorithm efficiently utilizes the cooperation in all traffic load scenarios based on the decision criteria and DTX mechanism. The results are compared with the existing AFEE and Green CoMP with Backhaul Traffic algorithm. In all the traffic loads EEAFR save 59.8% energy and reduces the network outage which depends on the failure rate of the eNB components

If we consider learning as a meaning-making process where people construct shared knowledge, it becomes a social dialogical activity in which knowledge is the result of an active process of articulation and reflection within a context (Jonassen et al.). An important element of this belief is that conversation is at the core of learning because knowledge is language-mediated. Within this context, what makes a conversation worthwhile and meaningful is how it is structured, how it is managed by the participants, and most importantly, how it is understood. In particular, conversation is essential in learning situations where the main goal is to generate a new understanding of the world (Bruner). Thus, if conversations can be seen as support for learning processes, the question then becomes how synchronous textual spaces mediate conversation and how chat affects learning. Experienced Teachers Learning in a Collaborative Virtual Environment We studied two different groups of experienced teachers from Kindergarten to Grade 12 (K-12) attending a Master of Education course entitled "Curriculum and Instruction". They communicated through a collaborative virtual environment (CVE) designed to enhance teachers' professional development: TAPPED IN™ (TI). We recorded their on-line conversations over six weeks. The teachers met twice a week for a two hour session and the data collected consisted of approximately 350-400 pages of text from transcripts. The following concerns, gleaned from an ongoing analysis of on-line conversations are of interest for this paper: The first concern has to do with the ability of teachers to concentrate on a task while managing multiple simultaneous conversations. The question is how to maintain the focus on the purpose of the goal oriented task. The second concern is related to the technical characteristics of a CVE and the teachers' feelings of being lost, too slow, or not understanding the point of the discussion. The question is how to deal with this confusion when the aim is to construct meanings from online discussion? The third concern is related the preceding points. It is concerned with the importance of a leader coaching and guiding experienced teachers online. We examined these three concerns, using TI during the teachers' on line discussions. Our primary goal in the analysis was to determine i) whether the teachers could conduct their learning activities through TI and ii) how goal-oriented conversations might be affected by the constraints of TI. The following examples come from a personal recorder. Messages are numbered in order to show their position in the session and to show the distance between the messages sent. Implications of Multitasking in Learning Sessions In CVEs, participants have the possibility of performing several tasks simultaneously (Holmevik). This is especially true when participants hold more than one conversation at a time. Participants can talk to one person or to the whole group while also chatting privately with people in the same CVE's room, in the same CVE or even in other CVEs. But the possibility of being able to participate in multiple conversations becomes potentially confusing and disorienting for teachers wanting to achieve a specific task. Let us give an example of how a main task (e.g. to share notes of pedagogical projects -- task 1) fragments into different tasks (e.g. learning a command -- how to create a note -- task 2; and socialise, express feelings and play with cows -- task 3). (Note that the students are in fact experienced teachers and a teacher is leading the session. The goal of the on-line session is to read and discuss the different educational projects that the students should have written in virtual notes.) The goal of the task became difficult to accomplish for teachers who were suddenly involved in more than one task at a time. In order to understand what is going on in this situation, participants had to accomplish extra work. They needed to filter messages and rank them to make the main objective of the session clear. In a goal-oriented session such as this, it is extremely important to keep track of the task as well as to concentrate on one activity at time. This entails a necessity to understand current threads in order to contribute to the object of interest for them as individuals and as a group member. Implications of Multi Threads and Floor-Taking in Goal-Oriented Conversations Perseverance with each message creates a parallelism that can become extremely disorienting to participants who intend to produce new understandings and not just maintain an awareness during on-line conversations. The larger the number of participants in a conversation, the more likely it is for fragmentation to occur. The jumbled and quickly scrolling screen can be quite disconcerting. Yet as mentioned by Mynatt et al., even between two participants, multi-threading is common due to the overlapping composition of conversational turns. Participants write simultaneously and the host computer sends the messages out sequentially. Under these conditions, competing conversational threads emerge continuously. It becomes difficult to know who actually holds the floor at the time. Here is an example showing a teacher -- student 2 -- looking for attention and trying to read and understand others' answers to his questions: Student 2 did not read message 26 sent from the teacher with care. In fact, the teacher did explain that there is a part in the assignment where students have to meet in order to exchange ideas about individual projects. Yet although S2's question was answered, S2 still did not understand. A possible reason is that S2 could have been focussed on writing the next question. Again, the teacher answered the question asked in message 29. However, S2 still did not understand in spite of S15 and S6 confirming that the teacher had already covered the question. Student 2 finally understood when the teacher addressed him directly and repeated what the other students had said before. In order to be heard, the students repeated their questions until they had the answer from the teacher. With more than a handful of participants, this attention seeking strategy may make on-line conversations confusing. Goal-oriented conversations then easily degenerate, as mentioned by Colomb and Simutis. These authors point out that one of the most common problems in using CMC is keeping students on task. Even experienced teachers do not escape from the possibility of converting from an instrumental discussion to a social one due to different misunderstanding between interlocutors. To be able to 'send' a message is not equivalent to claiming the 'floor'. An important extra task that teachers have to do in CVEs before sending a message is to think about how it meets the goal of the discussion. Looking for coherence and understanding is a must in learning situations and this becomes a great challenge in online learning sessions. On the other hand, different modalities of communication in CVEs may add richness and depth to online conversations when participants can anticipate constraints. Consider another group of teachers. They are discussing readings, and make great use of multiple modalities, such as gestures, to reframe misunderstandings. These gestures provide back channel information and other visual signs. Here is one example of what a group of teachers does in order to avoid embarrassing situations. As Mynatt et al. express, "the availability of multiple modalities gives complexity to the interactional rhythm, because people have choices about what modality to use at any particular moment and for any set of conversation partners" (138). Given these pros and cons of CVEs, the challenge of holding an on-line educational discussion requires the teachers to reestablish the context and control the underlying the sense of the conversation. This challenge could be also regarded as an exigency of the medium that 'invites' teachers to structure their conversations in order to encourage meaningful discussions. Importance of a Teacher of Teachers The problems mentioned earlier may be solved more easily when there is a leader at hand. Since these difficulties mainly arise at the start of learning the communication environment, it might be proposed that a leader is most critical in this phase. A comparison of two groups' interactions with and without a leader supports the intuition that a leader is crucial for keeping the learning on track even though the participants are experienced teachers. In this example, the task that the group performed was the same: "learning to attach an icon to their ellipses representing their presence in the system". Table 1. Data related to groups with and without a teacher Groups Learners Icons attached Messages produced Time employed 1. Without leader 12 0 549 56 min 8 sec 2. With leader 9 4 644 1h 27min 52 sec Fig. 1 Comparing flow and categories of the messages sent by the groups These frequencies confirm that teachers without a leader have more problems than the group with a leader. The number of successful icons attached by the groups (0 and 4 icons) demonstrates this claim. What happens is that the number of messages related to 'Task' decrease and those related to 'Relation' increase when there is no leader present -- a result which would be unsurprising among most people who have worked in 'real' classrooms. Messages produced and coded as 'Playing' and 'Feedback' also show a considerable difference between groups. Finally, categories such as 'Whisper' and 'Artifact' present in comparison to the others minimal differences between groups. A leader is a must for the smooth development of on-line conversation. The leader is a sort of mediator between the pedagogical task of the on-line conversation and what appears on the screen. The leader's task is to show which threads are important to follow or not and how messages should be read on the screen. Like an orchestra conductor, the leader coordinates tasks and makes sense of individual actions which are part of a common product and the quality of the on-going conversation. Discussion This ongoing research has demonstrated three important concerns surrounding experienced teachers' professional use of CVE. First, teachers chatting online have to anticipate the lack of assurance "that what gets sent gets read" and that gaining the floor in a CVE is "that one's message draws a response and in some way affect the direction of a current thread" (Colomb and Simutis). Teachers have to learn to negotiate turn-taking sequences behind the screen. When chatting, a person's intention to speak is not signalled. Overlapping and interruptions do not exist and non-verbal communication requires knowledge of gesture commands. Negotiating turns in online conversations is concerned with how people express information and what they express. In educational discussion, turns are generally taken when messages either present a good formulation of ideas, express controversial thinking, raise an issue that allows someone else to participate, or provide knowledge on the topic at hand. Second, teachers should learn to collaborate in online conversations. It is essential to be aware that people are writing a text while they discuss. The quality of the conversation will depend on one hand, how teachers manage the discussion and, on the other hand, the opinions they elaborate together. Third, teachers need leaders in online discussions. A leader has to be able to anticipate the text that the participants are writing. The leader has the responsibility of meeting pedagogical goals with a participant's messages. The leader has to show the coherence or incoherence of the discussion and raise issues that improve the level of the written interaction. These issues are extremely important in a context where people learn through conversations. As Laurillard has mentioned, "academic knowledge relies heavily on symbolic representation as the medium through which it is known. ... Students have to learn to handle the representations system as well as the ideas they represent" (27). Therefore, it is necessary that learners know and think about the rules of online discussion in order to adapt technical commands and effects to their needs. But these rules are in contrast to what participants expect from online conversations. Teachers want to perform their tasks with support of a computer program; they do not want to learn the computer program per se. CMC in learning activities must be based, not on visionary claims about technology as an all-purpose tool for automatic teaching/learning, but on specific accounts of how and why the technology affects the user's achievement of specific goals. Acknowledgements This study has been supported by a grant from the Swedish Transport & Communication Research Board. We wish to express our gratitude to Judi Fusco, who, in several ways, has been a bridge between the TI community and us. We also want to thank the teachers, CharlesE and FlorenceE, for having the courage of letting Tessy 'sit in' on the sessions. The 'expert' session was lead by TerryG, whom we also want to thank for her generosity. Susan Wildermuth came to us in the final spurt, and we owe her much for the reliability check, structuring of ideas, and hints about related research. Finally, all students struggling with TI are thanked for their willingness to participate in this study. References Cherny, L. Conversation and Community. Chat in a Virtual World. California: CSCLI Ed, 1999. Colomb, and Simutis. "Visible Conversations and Academic Inquiry: CMC in a Culturally Diverse Classroom." Computer-Mediated Communication: Linguistic, Social and Cross-Cultural Perspectives. Ed. Susan Herring. Philadelphia: John Benjamins, 1996. 203-24. Bruner, Jerome. Acts of Meanings. Cambridge, MA: Harvard UP, 1990. Holmevik, J., and C. Haynes. MOOniversity. A Student's Guide to Online Learning Environments. Boston: Allyn and Bacon, 2000. Jonassen, D., et al. "Constructivism and Computer-Mediated Communication." Distance Education 9.2 (1992): 7-25. Laurrillard, Diana. Rethinking University Teaching: A Framework for the Effective Use of Educational Technology. London: Routledge, 1994. Mynatt, E. D., et al. "Network Communities: Something Old, Something New, Something Borrowed." Computer Supported Cooperative Work: The Journal of Collaborative Computing 7.1-2 (1998): 123-56. Schlager, M., J. Fusco, and P. Schank. "Evolution of an On-line Education Community of Practice." Building Virtual Communities: Learning and Change in Cyberspace. Ed. K. Ann Renninger and W. Shumar. NY: Cambridge UP, 2000. Wærn, Yvonne. "Absent Minds -- On Teacher Professional Development." Journal of Courseware Studies 22 (1999): 441-55. Citation reference for this article MLA style: Teresa Cerratto, Yvonne Wærn. "Chatting to Learn and Learning to Chat in Collaborative Virtual Environments." M/C: A Journal of Media and Culture 3.4 (2000). [your date of access] <http://www.api-network.com/mc/0008/learning.php>. Chicago style: Teresa Cerratto, Yvonne Wærn, "Chatting to Learn and Learning to Chat in Collaborative Virtual Environments," M/C: A Journal of Media and Culture 3, no. 4 (2000), <http://www.api-network.com/mc/0008/learning.php> ([your date of access]). APA style: Teresa Cerratto, Yvonne Wærn. (2000) Chatting to learn and learning to chat in collaborative virtual environments. M/C: A Journal of Media and Culture 3(4). <http://www.api-network.com/mc/0008/learning.php> ([your date of access]).

Disclaimer: The situation on PixelCanvas is constantly changing due to raids from both sides. The figures in this article represent the state as of April 2020. In the politicized digital environment, the superiority of the alt-right’s weaponization of memes is often taken for granted. As summarized in the buzzword-phrase “the left can’t meme”, the digital engagements of self-identified leftist activists are usually seen as less effective than the ones of the right: their attempts at utilizing Internet culture described as too “politically correct” and “devoid of humour”. This supposedly “immutable law of the Internet” (Dankulous Memeulon) often found confirmation in research.Described by Phillips and Milner, Internet culture – “a highly insular clique”, now seeping into popular culture – is by design rooted in liberalism and fetishized sight. Through its principles of “free speech”, “harmless fun”, and dehumanizing detachment of memes from real-life production and consequence, meme-sharing was enabling deception, “bigoted pollution”, and reinforcing white racial frames, regardless of intentions (Phillips and Milner). From Andersson to Nagle, many come to the conclusion that the left’s presence online is simply not organized, not active, not transgressive enough to appeal to the sensibilities of Internet culture. Meanwhile, the playful, deceptive online engagements of the alt-right are found to be increasingly viral, set to recruit numerous young rebels, hence upholding a cultural hegemony which has already transcended over to the offline world. This online right style is one where a rejection of morality and nihilistic nonconformity reign supreme – all packaged in carnivalesque laughter and identity-bending “trolling” (Nagle 28-39). Even if counterculture and transgression used to be domains of the left, nowadays the nihilistic, fetishizing landscape of online humour is popularized via alt-right aligned message boards like 4chan (Nagle 28-39).Left-wing alternatives, encompassed by Nagle in the term “Tumblr liberalism”, were often described as “fragmented” through identitarianism and call-out-culture, enclosed in echo chambers, “nannying, language policing, and authoritarian” (68-85). This categorization has been rightfully criticized for reductionism that lumps together diverse political strands, focuses on form only, and omits the importance of subcultural logic in its caricature of the censorious left (Davies). However, it would be difficult to deny that this is exactly how the online left is, unfortunately, often perceived by the right and liberals/centrists alike, evidenced by its niche quality.The solutions to the problem of the right’s dominance in the memeosphere – and their Gramscian cultural hegemony – offered by Phillips and Milner could include disavowing fetishized sight while maintaining “slapdash, quippy, and Internet Ugly” qualities to deconstruct meme culture’s whiteness; Davies suggests that “if the left is to have the same degree of success in translating online cultures into political movements then it needs to understand both the online world and its own IRL history”.Nonetheless, some strands of the online left have been rather close in style and form to the ones of the alt-right, despite their clear difference of “stance” (Shifman 367). In this article, I demonstrate an example of a multi-faceted, united, witty, and countercultural meme leftism on PixelCanvas.io (PixelCanvas): a nearly unlimited online canvas, where anyone can place coloured pixels with an obligatory cooldown time after each. Intended for creative expression, PixelCanvas became a site of click-battles between organized dichotomous extremes of the left and the alt-right, and is swarmed with political imagery. The right’s use of this platform has been already examined by Thibault, well-fitting into the consensus about the efficiency of right-wing online activity. My focus is the rebuttal of alt-right imagery that the radical left replaces with their own.With a brief account of PixelCanvas’s affordances and recounting the recent history of its culture wars, I trace the hybrid leftist activity on PixelCanvas to argue that it is comparably grounded in dissimulation and transgression to the alt-right’s. Based on the case study, I explore how certain strands of online left might reappropriate the carnivalesque, deceptive, and countercultural meme culture sensibilities and forms, while simultaneously rejecting its “bigoted pollution” (Phillips and Milner) aspects. While arguably problematic, these new strategies might be necessary to combat the alt-right’s hegemony in the meme environment – and by extension, in popular culture.PixelCanvas as a Metapolitical Platform of Culture WarsPixelCanvas affords a blend of 4chan-style open-access, no-login anonymity and the importance of organized collective effort. As described by Thibault, it is an “online ‘game’ that allows players to colour pixels ..., either collaborating or competing for the control of the shared space” (102). The obligatory cooldown period on PixelCanvas results in most of the works requiring either dedication of long periods of time or collaboration: as such, the majority of canvas art has a “shared authorship” (102). As a space for creative expression, PixelCanvas encourages expressing aspects of genuine personal identity (political views, sexuality, etc.) albeit reduced to symbols and memes that rarely remain personal. Although the primary medium of information transfer on the platform is visual, brief written catchphrases are also utilized. While the canvas is not lacking in free areas, competition for space is prevalent: between political viewpoints, nationalist groups (Bakalım), and other communities (PixelCanvas.io).Given this setup, it might be expected that battling for hegemony took over the game. The affordances of PixelCanvas as accepting anonymous unmoderated expressions of identity/political views encourage dissimulation similarly to boards such as 4chan; its immediate visual/one-liner focus overlaps with the prerequisites of meme culture. Meanwhile, the game’s competition aspect leads to large-scale organization of polarized metapolitical groups and to imagery that is increasingly larger, more taboo-breaking, and playful: meant to catch the eye of a viewer before the opponents do. PixelCanvas, as such, is a platform fitting into transgressive, trolling, fetishizing, and “liberal” affordances of Internet culture: the same affordances that made it, according to Nagle or Phillips and Milner, into a space of desensitized white supremacy and right-wing dominance.Such a setup may seem to work in favour of the 4chan-style raids and against the supposed identitarianism of “Tumblr liberalism”. One could recall the importance of united collective efforts on 4chan: from meme-sharing to Gamergate raids (Beran). Meanwhile, suggested by Citarella, a problem of the online left is its fragmentation, and its “poorly organized and smaller followings” (10). As he observed on Politigram, “DemSocs, Syndicalists, ML’s, AnComs, … and so on, all hated each other. The online right was equally divided but managed to coordinate cultural agitations” (Citarella 10).Indeed, the platform displayed the effects of alt-right virality multiple times, involving creations of self-identified Kekistanis (KnowYourMeme), anarcho-capitalists, 4chan-aligned “bronies” (My Little Pony fans), etc. However, since 2017, the left joined the game, becoming another example of a united, well-organized and strongly participatory group, which continuously resists alt-right attacks and establishes its own raids, often gaining an upper hand.Named “Battle of Pixelgrad”, the influx of leftist activity began to combat the forming Reich Iron Cross posted by “a user on 4chan's /pol/” which has caught the attention of Leftbook/meme groups and subreddits (PLK Wiki) (Wrigley). The groups involved spanned “all beliefs under a unified socialist umbrella” (Pixel Liberation Front) ranging from communism through anarchism subtypes to identity politics: all associating with the “left unity” flag that they replaced the Iron Cross with. Their efforts against alt-right raids were coordinated through Discord servers and a public Facebook group. Soon, a Facebook page for Left Unity Fighting Front (LUFF) was set up, with the PixelCanvas flag in the banner and the description: “We decided to form the new rival of 4chan, LUFF. We are the new united front of the internet. Promoting left unity, trolling Nazis, and taking on sectarianism.”Figure 1: The ’Left Unity’ flag. Source: https://pixelcanvas.io/@-1554,3594.The concept of left unity has been criticised before, as one that would lead to “the co-optation of anarchism under a Marxist leadership”, charged with the history of anarchist-Bolshevik clashes in USSR, and marred by a “lack of willingness among some Marxists to actually engage with anarchists in legitimate debate” (Springer). Still, the PixelCanvas left unity is one of the rare instances of Marxist, anarchist, and other leftist online groups working together on rather equal grounds, without cracking down on discourse and historical contexts: which is afforded by a subcultural logic and focus on combating a common enemy. The PixelCanvas leftists support common projects, readily bending their beliefs/ identity to create an efficient community that can resist 4chan: self-identifying as an “allyship” with anonymous “soldiers”/comrades belonging together on the left side of the pixel “war” (Pixel Liberation Front). While the diversity of their beliefs is made clear through the variously aligned flags/thinkers they choose to represent with pixels, the union stands without in-fighting, emulating simplistic versions of history as a dichotomous struggle between left and right (which deliberately rejects centrism): from Nazi/communist battles to Cold War imagery. Although reductionist, this us/them thinking is especially necessary in the visual, time-sensitive, and competitive space of PixelCanvas. No matter how extreme the common projects are, what matters in the pixel war is camaraderie and defeating the enemy in the most striking manner possible. After all, the setup of the platform (and the immediacy of Internet culture) supports attention- grabbing transgression and memes better than nuanced discourse. Figure 2: Representation of the left uniting against Nazism and anarcho-capitalism. Source: https://pixelcanvas.io/@-143,-782.As of April 2020, hardly any Nazi/4chan/ancap imagery on PixelCanvas stands without being challenged by the Left Unity. Although some of the groups involved in Pixelgrad do not exist anymore, Discord servers (e.g. RedPixel) and Pixel Liberation Front (PLF) Facebook group remain, defending the platform from continued raids. These coordinating bodies are easily accessible to anyone willing to contribute (shall one wish for complete anonymity, they are also free to participate without joining the servers). Their efforts could be understood as “clicktivism” (Halupka); however, the involved leftists view it as a “war” (PLF) or “Memeolution” (Wrigley), an important way in which the “virality of right-wing populism” (Thibault) must be resisted. This use of language highlights their serious awareness of the need for combating the right’s digital hegemony, no matter how playful their activity seems.Even if this phenomenon is specific to PixelCanvas, one should acknowledge that the identity-bending unity of the left has been enough to challenge continued raids. Niche practices, as seen through 4chan, might break into the mainstream: according to Hobson and Modi, online spaces “are a rich recruiting ground for previously antithetical/apolitical young people” (345) who find refuge in memes and trolling. The agenda of the PixelCanvas left (counterplatforming activism) in this case differs from 4chan’s. However, the forms they assume to reach their goal are often “pithy, funny, or particularly striking” enough to potentially make one “pause to think, and/or laugh” (Hobson and Modi 345) regardless of political alignment.The Form, Content, and Stance of PixelCanvas Left ActivityDespite the unity in the organization of the PixelCanvas left, the approaches/strategies of its various pixel artworks are far from uniform. At the first sight, the creations of RedPixel members already appear as a multi-faceted (and potentially confusing) mixture of serious real-life agenda and playful Internet culture. Guided by Shifman’s communication-oriented typology of memes, I analyze the different “contents, forms, and stances” (367) that the PixelCanvas left displays in its creations. For analytical clarity, I distinguish three main approaches which overlap and play various roles in contributing to the collective image of RedPixel as simultaneously activist, serious, inclusive, and Internet-culture-savvy, transgressive, deceptive.The first approach of PixelCanvas leftist creations is most serious and least grounded in Internet culture. A portion of RedPixel activity directly reproduces real-life protest chants, posters, flags, murals, movement symbols, and portraits of leftist icons, with little alteration to the form other than pixelating. The contents of such creations vary, however, they remain serious and focused on real-life issues: voicing support for contemporary leftist movements (Black Lives Matter, pro-refugee, Rojava liberation, etc.), celebrating the countercultural, class-centric leftist history (anarchist, communist, socialist victories, thinkers, and revolutionaries), and representing a plethora of identities within hyper-inclusive flag clusters (of various sexualities, genders, and ethnicities). The stance of these images can be plausibly interpreted as charged with serious/genuine “keying” (Shifman 367), and “conative” (imperative) or “emotive” (367) functions. Within those images, the meme culture’s problematic affordances (“fetishization” and “liberalism” (Phillips and Milner)) are disavowed clearly: exemplified by a banner on the site suggesting that “just a meme” mentality created a shield for “meme Nazis” that led to the 2019 Christchurch mosque shooting. Although this strand of RedPixel’s works could be criticized as “humourless” and rather detached from the platform’s affordances, its role lies in displaying the connection to the real world with potential suggestions for mobilization, the awareness of meme culture’s problematic nature, and the image of radical left cooperation. Figure 3: The Christchurch memorial. Source: https://pixelcanvas.io/@-2815,3321. Figure 4: Posters and symbols in support of Rojava, Palestine liberation, and Black Lives Matter. Source: https://pixelcanvas.io/@5340,4121. Figure 5: Early Paris Commune poster reproduced on PixelCanvas. Source: https://pixelcanvas.io/@7629,2134. Figure 6: Example of a PixelCanvas hyper-inclusive flag cluster. Source: https://pixelcanvas.io/@2741,-3508.The second approach, while similar in the diversity of content, adopts memetic forms, and the light-hearted “harmless fun” of Internet culture. Through popular meme formats (molded to call for action), slang expressions, pop-cultural references (anime/cartoon/video game characters), to adopting “cutesy” aesthetics, these creations present identity politics, anti-fascism, and anti-capitalism in a light, aestheticized form. Popular characters, colourful art, and repetitive base colour schemes (red, black, rainbow) are likely to attract attention; recognition of the pop-cultural references, and of known meme formats might sustain it, urging one to focus on the only uncertain element: the politics behind it. Being visually and contextually appealing to online youth, this political-memetic imagery is well-adapted to the platform. Simultaneously, the carnivalesque forms contrast with the frequently more transgressive contents this approach employs. As a result, the tone of their work seems lighthearted even in its incitement to “kill the Nazis” and “eat the rich”. Clearly aware of the language of its opposition, RedPixel reacts similarly to how 4chan reacted to Tumblr liberalism: responding to “lightly thrown accusations” (Nagle) by intensifying them to the point where they can be seen as “owning” the labels they have been given – instead of “getting offended”. Through memes and reappropriated posters they present themselves as “Red Menace,” as a direct threat to 4channers, and as a “trigger-warning” club, using the existing criticisms to self-identify as formidable enemies of the right. While the transgression in RedPixel style often remains acceptable by radical left standards, it is certainly not the same as “virtue signalling”, “hypersensitive”, “vulnerable” Tumblr liberalism (Nagle 68–85); and it might be shocking or amoral to some. Much of their imagery is provocative: inciting violence, glorifying deeply problematic parts of communist history, using religious symbols in a potentially blasphemous way, supporting occultism/ Satanism, and explicitly amplifying (queer) sexuality. In the mix of (sometimes) extreme contents and forms that suggest a light-hearted attitude, it might be difficult to determine the keying of their stance. Although it is unlikely that RedPixel would avow politics they do not actually believe (given the activist, anti-fetishizing agenda of their first approach), their political choices are frequently amplified to their full “tankie” form, and even up to Stalin support: raising the question how much of it is serious intent masked with humour, and what could be written off as deliberate identity play, deceptive “trolling” and jokes, similar in style to 4chan’s. Figure 7: Revolution-inciting appropriation of a popular meme format. Source: https://pixelcanvas.io/@-1765,3376. Figure 8: Fictional characters Stevonnie (Steven Universe) and Cirno (Touhou) with leftist captions. Source: https://pixelcanvas.io/@-847,-748. Figure 9: Call for fighting fascism referencing a Pacman video game and Karl Marx. Source: https://pixelcanvas.io/@-712,-395. Figure 10: Joseph Stalin reimagined as a My Little Pony character. Source: https://pixelcanvas.io/@-1197,966. Figure 11: “A spectre is haunting Kekistan.” Source: https://pixelcanvas.io/@-2196,3248. Figure 12: “Trigger Warning Gun Club” badge. Source: https://pixelcanvas.io/@2741,-3508.Figure 13: “Have you heard that Nazis get vored?” anime catgirl. Source: https://pixelcanvas.io/@1684,928. Figure 14: Rainbow genitals on a former Kekistan flag. Source: https://pixelcanvas.io/@-2513,3221. Figure 15: “Eat the Rich — OK Boomer” wizard ghost. Source: https://pixelcanvas.io/@-4390,-697.The third approach can be read as a subset of the second: however, what distinguishes it is a clearly parodic stance and reappropriating of 4chan’s forms. The PixelCanvas activists, unlike the supposed “anti-free speech” left (Lukianoff and Haidt) do not try to get the alt-right imagery removed by others, and do not fully erase it. Instead, they repurpose 4chan memes and flags, ridiculing them or making them stand for leftist views. An unaware viewer could mistake their parodies of 4chan for parodies of the left made by 4chaners; the true stance sometimes only suggested by their placement within RedPixel-reclaimed areas. Communist and LGBTQ+ Pepes or Ponies, modified Kekistan flags, and even claiming that “the right can’t meme” all point to an interesting trend that instead of banning symbols associated with alt-right groups wants to exploit the malleability of memes: confusing and parodying their original content and stance while maintaining the form and style. This aim is perhaps best exemplified in the image The Greatest Game of Capture the Flag where Pepes in anarcho-communist, communist, and transgender Pride hoodies are escaping from a crying white man while carrying a 4chan flag. Interpreted in context, this image summarizes the new direction that leftists take against 4chan. This is a direction of left unity (with various strands of radical left maintaining their identities but establishing an overarching collective “allyship” identification), of mixing identity politics with classic ideologies, of reconciling Internet culture with IRL socio-political awareness, and finally, of reappropriating proven-effective play, dissimulation, and transgression from 4chan. Figure 16: Pride flag cluster with Pride-coloured Pepes. Source: https://pixelcanvas.io/@-1599,3516. Figure 17: Communist/anarchist thinkers and leaders reimagined as Pepes. Source: https://pixelcanvas.io/@-1885,3203. Figure 18: “The Right Can’t Meme.” Source: https://pixelcanvas.io/@-1885,3203. Figure 19: The reclaimed Kekistan area. Source: https://pixelcanvas.io/@-2439,3210. Figure 20: “The Greatest Game of Capture the Flag.” Source: https://pixelcanvas.io/@-1885,3203.ConclusionThe PixelCanvas left can serve as an example of a united stronghold which managed to counterplatform the alt-right: assuming dominance in 2017 to later rebuild and expand their pixel spheres of influence after each 4chan raid. Online culture wars are nowadays recognized as Gramscian in their roots: according to Burton, “the young people confronting this reactionary shift head-on with memes normalizing are … on the front lines of a culture war with global repercussions” (13). By far, this “war” for digital hegemony has been overwhelmingly evaluated as one that the alt-right is simply better at, due to the natural affordances of Internet culture. However, the “united front of the internet” “promoting left unity and trolling Nazis” (LUFF) exemplifies a possible direction which the online radical left could follow to take on 4chan’s digital dominance. This direction is complex and hybrid: with overlapping/combined approaches. The activities of PixelCanvas left include practices that are well-adapted to the immediate meme culture and those based on IRL movements; practices similar to 4chan’s problematic transgression and those that are activist, disavowing fetishized sight; serious practices and deceptive/ironic ones. Their 2017 PixelCanvas victory and later resistance persisting despite continuing raids might suggest that this strategy works, with the key to its coordination laying in the subcultural logic of an “allyship” that privileges fast-paced mobilization and swift comebacks over careful nuance: necessitated by meme culture affordances. Although only time can prove if this new left digital language will become more widespread, it has the potential to become an alternative to “hypersensitive Tumblr liberalism” and to challenge the idea that meme culture is doomed to be right-wing.ReferencesAndersson, Linus. “No Digital ‘Castles in the Air’: Online Non-Participation and the Radical Left.” Media and Communication 4.4 (2016): 53–62.Bakalım, Seyret. “Pixel io Türkiye vs Brezilya [Turkey vs Brazil] Pixel War.” YouTube, 23 June 2017. <https://www.youtube.com/watch?v=NsPHVNpB8Hg>.Beran, Dale. “4chan: The Skeleton Key to the Rise of Trump.” Medium, 14 Feb. 2017. <https://medium.com/@DaleBeran/4chan-the-skeleton-key-to-the-rise-of-trump-624e7cb798cb>.Burton, Julian. “Look at Us, We Have Anxiety: Youth, Memes, and the Power of Online Cultural Politics.” Journal of Childhood Studies 44.3 (2019): 3–17.Dankulous Memeulon. “The Left Can’t Meme.” UrbanDictionary, 11 May 2018. <https://www.urbandictionary.com/define.php?term=The%20Left%20can%27t%20Meme>.Davies, Josh. “Tumblr Liberalism’ vs the Serious Authentic Left: On Angela Nagle’s Kill All Normies.” Ceasefire Magazine, 8 Sep. 2017. <https://ceasefiremagazine.co.uk/tumblr-liberalism-authentic-left-review-kill-normies/>.Halupka, Max. “Clicktivism: A Systematic Heuristic.” Policy & Internet 6.2 (2014): 115–32.Hobson, Thomas, and Kaajal Modi. “Socialist Imaginaries and Queer Futures: Memes as Sites of Collective Imagining.” Post Memes: Seizing the Memes of Production. Eds. Alfie Bown and Dan Bristow. New York: Punctum Books, 2019. 327–52.KnowYourMeme. “Kekistan.” KnowYourMeme, 2017. <https://knowyourmeme.com/memes/kekistan>.Left Unity Fighting Front. “About.” Facebook, 6 July 2017. <https://www.facebook.com/pg/LeftUnityFightingFront/about/>.Lukianoff, Greg, and Jonathan Haidt. The Coddling of the American Mind. New York: Penguin Books, 2018.Nagle, Angela. Kill All Normies: Online Culture Wars from 4chan and Tumblr to Trump and the Alt-Right. Winchester, Washington: Zero Books, 2017.Phillips, Whitney, and Ryan M. Milner. “The Root of All Memes.” You Are Here, 27 Apr. 2020. <https://you-are-here.pubpub.org/pub/wsl350qp/release/1>.PixelCanvas. <https://pixelcanvas.io/>.PixelCanvas.io. “PixelCanvas.io | The Death of Pac-Man - The Void vs SDLG.” YouTube, 19 June 2017. <https://www.youtube.com/watch?v=gV70eV38z3A>.Pixel Liberation Front. “About.” Facebook, 8 June 2017. <https://www.facebook.com/groups/1933096136902765/about/>.PLK Wiki. “Battle of Pixelgrad.” PLK Wiki, 2017. <https://plk.fandom.com/wiki/Battle_of_Pixelgrad>.QueenButtrix. “Brocialist.” Urban Dictionary, 18 Sep. 2016. <https://www.urbandictionary.com/define.php?term=brocialist>.Shifman, Limor. “Memes in a Digital World: Reconciling with a Conceptual Troublemaker.” Journal of Computer-Mediated Communication 18.3 (2013): 362–377.Springer, Simon. “Who's Afraid of the Big Bad Anarchist? Rejecting Left Unity and Raising Hell in Radical Geography.” Anarchist Studies, 28 Jan. 2018. <https://anarchiststudies.noblogs.org/whos-afraid-of-the-big-bad-anarchist-rejecting-left-unity-and-raising-hell-in-radical-geography/>.Thibault, Mattia. “A Picture of the Internet: Conflict, Power and Politics on Pixelcanvas.” Virality and Morphogenesis of Right-Wing Internet Populism. Eds. Eva Kimminich and Julius Erdmann. Berlin: Peter Lang, 2018. 102–12.TheCissKing. “Tucute.” Urban Dictionary, 17 Jan. 2019. <https://www.urbandictionary.com/define.php?term=tucute>.Wrigley, Jack. “Battle of Pixelgrad.” YouTube, 24 July 2017. <https://www.youtube.com/watch?v=ZJa1Hi2j1_E>.

The digital revolution has been characterized by the overlapping of different media technologies and platforms which reshaped both traditional forms of audiovisual consumption and older conceptions of place and space. John Agnew claims that, traditionally, the notion of place has been associated with two different meanings: ‘the first is a geometric conception of place as a mere part of space and the second is a phenomenological understanding of a place as a distinctive coming together in space’ (317). Both of the dominant meanings have been challenged by the idea that the world itself is increasingly “placeless” as space-spanning connections and flows of information, things, and people undermine the rootedness of a wide range of processes anywhere in particular (Friedman). On the one hand, by obliterating physical distance, new technologies such as the Internet and the cell phone are making places obsolete, on the other hand, the proliferation of media representations favoured by these technologies are making places more relevant than ever. These increasing mediatisation processes, in fact, generate what Urry and Larsen call ‘imaginative geographies’, namely the conflation of representational spaces and physical spaces that substitute and enhance each other in contingent ways (116). The smartphone as a new hybrid media platform that combines different technological features such as digital screens, complex software applications, cameras, tools for online communication and GPS devices, has played a crucial role in the construction of new notions of place. This article examines a specific type of phone applications: mobile, digital mapping tools that allow users to identify film-locations. In doing so it will assess how new media platforms can potentially reconfigure notions of both media consumption, and (physical and imagined) mobility. Furthermore, the analysis of digital movie maps and their mediation of film locations will shed light on the way in which contemporary leisure activities reshape the cultural, social and geographic meaning of place. Digital, Mobile Movie MapsDigital movie maps can be defined as software applications, conceived for smart phones or other mobile devices, which enable users to identify the geographical position of film locations. These applications rely on geotagging which is the process of adding geospatial metadata (usually latitudinal and longitudinal coordinates) to texts or images. From this point of view these phone apps belong to a broader category of media that Tristan Thielmann calls geomedia: converging applications of interactive, digital, mapping tools and mobile and networked media technologies. According to Hjorth, recent studies on mobile media practices show a trend toward “re-enacting the importance of place and home as both a geo-imaginary and socio-cultural precept” (Hjorth 371). In 2008 Google announced that Google Maps and Google Earth will become the basic platform for any information search. Similarly, in 2010 Flickr started georeferencing their complete image stock (Thielmann 8). Based on these current developments media scholars such as Thielmann claim that geomedia will emerge in the future as one of the most pervasive forms of digital technology (8).In my research I identified 44 phone geomedia apps that offered content variously related to film locations. In every case the main functionality of the apps consisted in matching geographic data concerning the locations with visual and written information about the corresponding film production. ‘Scene Seekers’, the first app able to match the title of a film with the GPS map of its locations, was released in 2009. Gradually, subsequent film-location apps incorporated a number of other functions including:Trivia and background information about films and locationsSubmission forms which allow users to share information about their favourite film locatiosLocation photosLinks to film downloadFilm-themed itinerariesAudio guidesOnline discussion groupsCamera/video function which allow users to take photos of the locations and share them on social mediaFilm stills and film clipsAfter identifying the movie map apps, I focused on the examination of the secondary functions they offered and categorized the applications based on both their main purpose and their main target users (as explicitly described in the app store). Four different categories of smart phone applications emerged. Apps conceived for:Business (for location scouts and producers)Entertainment (for trivia and quiz buffs)Education (for students and film history lovers)Travel (for tourists)‘Screen New South Wales Film Location Scout’, an app designed for location scouts requiring location contact information across the state of New South Wales, is an example of the first category. The app provides lists, maps and images of locations used in films shot in the region as well as contact details for local government offices. Most of these types of apps are available for free download and are commissioned by local authorities in the hope of attracting major film productions, which in turn might bring social and economic benefits to the region.A small number of the apps examined target movie fans and quiz buffs. ‘James Bond and Friends’, for example, focuses on real life locations where spy/thriller movies have been shot in London. Interactive maps and photos of the locations show their geographical position. The app also offers a wealth of trivia on spy/thriller movies and tests users’ knowledge of James Bond films with quizzes about the locations. While some of these apps provide information on how to reach particular film locations, the emphasis is on trivia and quizzes rather than travel itself.Some of the apps are explicitly conceived for educational purposes and target film students, film scholars and users interested in the history of film more broadly. The Italian Ministry for Cultural Affairs, for example, developed a number of smartphone apps designed to promote knowledge about Italian Cinema. Each application focuses on one Italian city, and was designed for users wishing to acquire more information about the movie industry in that urban area. The ‘Cinema Roma’ app, for example, contains a selection of geo-referenced film sets from a number of famous films shot in Rome. The film spots are presented via a rich collection of historical images and texts from the Italian National Photographic Archive.Finally, the majority of the apps analysed (around 60%) explicitly targets tourists. One of the most popular film-tourist applications is the ‘British Film Locations’ app with over 100,000 downloads since its launch in 2011. ‘British Film Locations’ was commissioned by VisitBritain, the British tourism agency. Visit Britain has attempted to capitalize on tourists’ enthusiasm around film blockbusters since the early 2000s as their research indicated that 40% of potential visitors would be very likely to visit the place they had seen in films or on TV (VisitBritain). British Film Locations enables users to discover and photograph the most iconic British film locations in cinematic history. Film tourists can search by film title, each film is accompanied by a detailed synopsis and list of locations so users can plan an entire British film tour. The app also allows users to take photos of the location and automatically share them on social networks such as Facebook or Twitter.Movie Maps and Film-TourismAs already mentioned, the majority of the film-location phone apps are designed for travel purposes and include functionalities that cater for the needs of the so called ‘post-tourists’. Maxine Feifer employed this term to describe the new type of tourist arising out of the shift from mass to post-Fordist consumption. The post-tourist crosses physical and virtual boundaries and shifts between experiences of everyday life, either through the actual or the simulated mobility allowed by the omnipresence of signs and electronic images in the contemporary age (Leotta). According to Campbell the post-tourist constructs his or her own tourist experience and destination, combining these into a package of overlapping and disjunctive elements: the imagined (dreams and screen cultures), the real (actual travels and guides) and the virtual (myths and internet) (203). More recently a number of scholars (Guttentag, Huang et al., Neuhofer et al.) have engaged with the application and implications of virtual reality on the planning, management and marketing of post-tourist experiences. Film-induced tourism is an expression of post-tourism. Since the mid-1990s a growing number of scholars (Riley and Van Doren, Tooke and Baker, Hudson and Ritchie, Leotta) have engaged with the study of this phenomenon, which Sue Beeton defined as “visitation to sites where movies and TV programmes have been filmed as well as to tours to production studios, including film-related theme parks” (11). Tourists’ fascination with film sets and locations is a perfect example of Baudrillard’s theory of hyperreality. Such places are simulacra which embody the blurred boundaries between reality and representation in a world in which unmediated access to reality is impossible (Baudrillard).Some scholars have focused on the role of mediated discourse in preparing both the site and the traveller for the process of tourist consumption (Friedberg, Crouch et al.). In particular, John Urry highlights the interdependence between tourism and the media with the concept of the ‘tourist gaze’. Urry argues that the gaze dominates tourism, which is primarily concerned with the commodification of images and visual consumption. According to Urry, movies and television play a crucial role in shaping the tourist gaze as the tourist compares what is gazed at with the familiar image of the object of the gaze. The tourist tries to reproduce his or her own expectations, which have been “constructed and sustained through a variety of non-tourist practices, such as film, TV, literature, records, and videos” (Urry 3). The inclusion of the camera functionality in digital movie maps such as ‘British Film Locations’ fulfils the need to actually reproduce the film images that the tourist has seen at home.Film and MapsThe convergence between film and (virtual) travel is also apparent in the prominent role that cartography plays in movies. Films often allude to maps in their opening sequences to situate their stories in time and space. In turn, the presence of detailed geographical descriptions of space at the narrative level often contributes to establish a stronger connection between film and viewers (Conley). Tom Conley notes that a number of British novels and their cinematic adaptations including Tolkien’s The Lord of the Rings (LOTR) and Stevenson’s Treasure Island belong to the so called ‘cartographic fiction’ genre. In these stories, maps are deployed to undo the narrative thread and inspire alternative itineraries to the extent of legitimising an interactive relation between text and reader or viewer (Conley 225).The popularity of LOTR locations as film-tourist destinations within New Zealand may be, in part, explained by the prominence of maps as both aesthetic and narrative devices (Leotta). The authenticity of the LOTR geography (both the novel and the film trilogy) is reinforced, in fact, by the reoccurring presence of the map. Tolkien designed very detailed maps of Middle Earth that were usually published in the first pages of the books. These maps play a crucial role in the immersion into the imaginary geography of Middle Earth, which represents one of the most important pleasures of reading LOTR (Simmons). The map also features extensively in the cinematic versions of both LOTR and The Hobbit. The Fellowship of the Ring opens with several shots of a map of Middle Earth, anticipating the narrative of displacement that characterizes LOTR. Throughout the trilogy the physical dimensions of the protagonists’ journey are emphasized by the foregrounding of the landscape as a map.The prominence of maps and geographical exploration as a narrative trope in ‘cartographic fiction’ such as LOTR may be responsible for activating the ‘tourist imagination’ of film viewers (Crouch et al.). The ‘tourist imagination’ is a construct that explains the sense of global mobility engendered by the daily consumption of the media, as well as actual travel. As Crouch, Jackson and Thompson put it, “the activity of tourism itself makes sense only as an imaginative process which involves a certain comprehension of the world and enthuses a distinctive emotional engagement with it” (Crouch et al. 1).The use of movie maps, the quest for film locations in real life may reproduce some of the cognitive and emotional pleasures that were activated while watching the movie, particularly if maps, travel and geographic exploration are prominent narrative elements. Several scholars (Couldry, Hills, Beeton) consider film-induced tourism as a contemporary form of pilgrimage and movie maps are becoming an inextricable part of this media ritual. Hudson and Ritchie note that maps produced by local stakeholders to promote the locations of films such as Sideways and LOTR proved to be extremely popular among tourists (391-392). In their study about the impact of paper movie maps on tourist behaviour in the UK, O’Connor and Pratt found that movie maps are an essential component in the marketing mix of a film location. For example, the map of Pride and Prejudice Country developed by the Derbyshire and Lincolnshire tourist boards significantly helped converting potential visitors into tourists as almost two in five visitors stated it ‘definitely’ turned a possible visit into a certainty (O’Connor and Pratt).Media Consumption and PlaceDigital movie maps have the potential to further reconfigure traditional understandings of media consumption and place. According to Nana Verhoeff digital mapping tools encourage a performative cartographic practice in the sense that the dynamic map emerges and changes during the users’ journey. The various functionalities of digital movie maps favour the hybridization between film reception and space navigation as by clicking on the movie map the user could potentially watch a clip of the film, read about both the film and the location, produce his/her own images and comments of the location and share it with other fans online.Furthermore, digital movie maps facilitate and enhance what Nick Couldry, drawing upon Claude Levi Strauss, calls “parcelling out”: the marking out as significant of differences in ritual space (83). According to Couldry, media pilgrimages, the visitation of TV or film locations are rituals that are based from the outset on an act of comparison between the cinematic depiction of place and its physical counterpart. Digital movie maps have the potential to facilitate this comparison by immediately retrieving images of the location as portrayed in the film. Media locations are rife with the marking of differences between the media world and the real locations as according to Couldry some film tourists seek precisely these differences (83).The development of smart phone movie maps, may also contribute to redefine the notion of audiovisual consumption. According to Nanna Verhoeff, mobile screens of navigation fundamentally revise the spatial coordinates of previously dominant, fixed and distancing cinematic screens. One of the main differences between mobile digital screens and larger, cinematic screens is that rather than being surfaces of projection or transmission, they are interfaces of software applications that combine different technological properties of the hybrid screen device: a camera, an interface for online communication, a GPS device (Verhoeff). Because of these characteristics of hybridity and intimate closeness, mobile screens involve practices of mobile and haptic engagement that turn the classical screen as distanced window on the world, into an interactive, hybrid navigation device that repositions the viewer as central within the media world (Verhoeff).In their discussion of the relocation of cinema into the iPhone, Francesco Casetti and Sara Sampietro reached similar conclusions as they define the iPhone as both a visual device and an interactive interface that mobilizes the eye as well as the hand (Casetti and Sampietro 23). The iPhone constructs an ‘existential bubble’ in which the spectator can find refuge while remaining exposed to the surrounding environment. When the surrounding environment is the real life film location, the consumption or re-consumption of the film text allowed by the digital movie map is informed by multi-sensorial and cognitive stimuli that are drastically different from traditional viewing experiences.The increasing popularity of digital movie maps is a phenomenon that could be read in conjunction with the emergence of innovative locative media such as the Google glasses and other applications of Augmented Reality (A.R.). Current smart phones available in the market are already capable to support A.R. applications and it appears likely that this will become a standard feature of movie apps within the next few years (Sakr). Augmented reality refers to the use of data overlays on real-time camera view of a location which make possible to show virtual objects within their spatial context. The camera eye on the device registers physical objects on location, and transmits these images in real time on the screen. On-screen this image is combined with different layers of data: still image, text and moving image.In a film-tourism application of augmented reality tourists would be able to point their phone camera at the location. As the camera identifies the location images from the film will overlay the image of the ‘real location’. The user, therefore, will be able to simultaneously see and walk in both the real location and the virtual film set. The notion of A.R. is related to the haptic aspect of engagement which in turn brings together the doing, the seeing and the feeling (Verhoeff). In film theory the idea of the haptic has come to stand for an engaged look that involves, and is aware of, the body – primarily that of the viewer (Marx, Sobchack). The future convergence between cinematic and mobile technologies is likely to redefine both perspectives on haptic perception of cinema and theories of film spectatorship.The application of A.R. to digital, mobile maps of film-locations will, in part, fulfill the prophecies of René Barjavel. In 1944, before Bazin’s seminal essay on the myth of total cinema, French critic Barjavel, asserted in his book Le Cinema Total that the technological evolution of the cinematic apparatus will eventually result in the total enveloppement (envelopment or immersion) of the film-viewer. This enveloppement will be characterised by the multi-sensorial experience and the full interactivity of the spectator within the movie itself. More recently, Thielmann has claimed that geomedia such as movie maps constitute a first step toward the vision that one day it might be possible to establish 3-D spaces as a medial interface (Thielmann).Film-Tourism, Augmented Reality and digital movie maps will produce a complex immersive and inter-textual media system which is at odds with Walter Benjamin’s famous thesis on the loss of ‘aura’ in the age of mechanical reproduction (Benjamin), as one of the pleasures of film-tourism is precisely the interaction with the auratic place, the actual film location or movie set. According to Nick Couldry, film tourists are interested in the aura of the place and filming itself. The notion of aura is associated here with both the material history of the location and the authentic experience of it (104).Film locations, as mediated by digital movie maps, are places in which people have a complex sensorial, emotional, cognitive and imaginative involvement. The intricate process of remediation of the film-locations can be understood as a symptom of what Lash and Urry have called the ‘re-subjectification of space’ in which ‘locality’ is re-weighted with a more subjective and affective charge of place (56). According to Lash and Urry the aesthetic-expressive dimensions of the experience of place have become as important as the cognitive ones. By providing new layers of cultural meaning and alternative modes of affective engagement, digital movie maps will contribute to redefine both the notion of tourist destination and the construction of place identity. These processes can potentially be highly problematic as within this context the identity and meanings of place are shaped and controlled by the capital forces that finance and distribute the digital movie maps. Future critical investigations of digital cartography will need to address the way in which issues of power and control are deeply enmeshed within new tourist practices. 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New York: Columbia University Press, 2013. 19-30.Claudell, Tom, and David Mizell. “Augmented Reality: An Application of Heads-Up Display Technology to Manual Manufacturing Processes.” Proceedings of 1992 IEEE Hawaii International Conference, 1992.Conley, Tom. “The Lord of the Rings and The Fellowship of the Map.” From Hobbits to Hollywood. Ed. Ernst Mathijs and Matthew Pomerance. Amsterdam: Rodopi, 2006. 215–30.Couldry, Nick. “The View from inside the 'Simulacrum‘: Visitors’ Tales from the Set of Coronation Street.” Leisure Studies 17.2 (1998): 94-107.Couldry, Nick. Media Rituals: A Critical Approach. London: Routledge, 2003. 75-94.Crouch, David, Rhona Jackson, and Felix Thompson. The Media and the Tourist Imagination. London: Routledge, 2005Feifer, Maxine. Going Places: The Ways of the Tourist from Imperial Rome to the Present Day. London: Macmillan, 1985.Friedberg, Anne. Window Shopping: Cinema and the Postmodern. Berkeley: University of California Press, 1993.Friedman, Thomas. The World Is Flat: A Brief History of the Twentieth Century. New York: Farrar, Strauss and Giroux, 2005.Guttentag, Daniel. “Virtual Reality: Applications and Implications for Tourism.” Tourism Management 31.5 (2010): 637-651.Hill, Matt. Fan Cultures. London: Routledge. 2002.Huang, Yu Chih, et al. “Exploring User Acceptance of 3D Virtual Worlds in Tourism Marketing”. Tourism Management 36 (2013): 490-501.Hjorth, Larissa. “The Game of Being Mobile. One Media History of Gaming and Mobile Technologies in Asia-Pacific.” Convergence 13.4 (2007): 369–381.Hudson, Simon, and Brent Ritchie. “Film Tourism and Destination Marketing: The Case of Captain Corelli’s Mandolin.” Journal of Vacation Marketing 12.3 (2006): 256–268.Jackson, Rhona. “Converging Cultures; Converging Gazes; Contextualizing Perspectives.” The Media and the Tourist Imagination. Eds. David Crouch et al. London: Routledge, 2005. 183-197.Kim, Hyounggon, and Sarah Richardson. “Motion Pictures Impacts on Destination Images.” Annals of Tourism Research 25.2 (2005): 216–327.Lash, Scott, and John Urry. Economies of Signs and Space. London: Sage, 1994.Leotta, Alfio. Touring the Screen: Tourism and New Zealand Film Geographies. London: Intellect Books, 2011.Marks, Laura. “Haptic Visuality: Touching with the Eyes.” Framework the Finnish Art Review 2 (2004): 78-82.Neuhofer, Barbara, Dimitrios Buhalis, and Adele Ladkin. ”A Typology of Technology-Enhanced Tourism Experiences.” International Journal of Tourism Research 16.4 (2014): 340-350.O’Connor, Noelle, and Stephen Pratt. Using Movie Maps to Leverage a Tourism Destination – Pride and Prejudice (2005). Paper presented at the 4th Tourism & Hospitality Research Conference – Reflection: Irish Tourism & Hospitality. Tralee Institute of Technology Conference, Tralee, Co. Kerry, Ireland. 2008.Riley, Roger, and Carlton Van Doren. “Films as Tourism Promotion: A “Pull” Factor in a “Push” Location.” Tourism Management 13.3 (1992): 267-274.Sakr, Sharif. “Augmented Reality App Concept Conjures Movie Scenes Shot in Your Location”. Engadget 2011. 1 Feb. 2016 <http://www.engadget.com/2011/06/22/augmented-reality-app-concept-conjures-movie-scenes-shot-in-your/>.Simmons, Laurence. “The Lord of the Rings: The Fellowship of the Ring.” The Cinema of Australia and New Zealand. Eds. Geoff Mayer and Keith Beattie. London: Wallflower, 2007. 223–32.Sobchack, Vivian. Carnal Thoughts: Embodiment and Moving Image Culture. Berkeley: University of California. 2004.Thielmann, Tristan. “Locative Media and Mediated Localities: An Introduction to Media Geography.” Aether 5a Special Issue on Locative Media (Spring 2010): 1-17.Tooke, Nichola, and Michael Baker. “Seeing Is Believing: The Effect of Film on Visitor Numbers to Screened Location.” Tourism Management 17.2 (1996): 87-94.Tzanelli, Rodanthi. The Cinematic Tourist. New York: Routledge, 2007.Urry, John. The Tourist Gaze. London: Sage, 2002.Urry, John, and Jonas Larsen. The Tourist Gaze 3.0. London: Sage, 2011.Verhoeff, Nana. Mobile Screens: The Visual Regime of Navigation. Amsterdam University Press, 2012.VisitBritain. “Films Continue to Draw Tourists to Britain.” 2010. 20 Oct. 2012 <http://www.visitbritain.org/mediaroom/archive/2011/filmtourism.aspx>.

Wandering the aisles of my local Woolworths in April this year, I noticed a large number of chocolate bilbies replacing chocolate rabbits. In these harsh economic times it seems that even the Easter bunny is in danger of losing his Easter job. While the changing shape of Easter chocolate may seem to be a harmless affair, the expulsion of the rabbit from Easter celebrations has a darker side. In this paper I look at the campaign to replace the Easter bunny with the Easter bilby, and the implications this mediated conservation move has for living rabbits in the Australian ecosystem. Essential to this discussion is the premise that studies of ecology must take into account the impact of media and culture on environmental issues. Of particular interest is the role of narrative, and the way the stories we tell about rabbits determine how they are treated in real life. While I recognise that the Australian bilby’s struggle for survival is a tale which should be told, I also argue that the vilification of the European-Australian rabbit is part of the native/invasive dualism which has ceased to be helpful, and has instead become a motivator of unproductive violence. In place of this simplified dichotomous narrative, I propose an ethic of "ecological remembrance" to combat the totalising eradication of the European rabbit from the Australian environment and culture. The Bilby vs the Bunny: A Case Study in "Media Selection" Easter Bunny says, ‘Bilby, I want you to have my job.You know about sharing and taking care.I think Australia should have an Easter Bilby.We rabbits have become too greedy and careless.Rabbits must learn from bilbies and other bush creatures’. The lines above are taken from Ali Garnett and Kaye Kessing’s children’s story, Easter Bilby, co-published by the Australian Anti-Rabbit Research Foundation as part of the campaign to replace the Easter bunny with the eco-politically correct Easter bilby. The first chocolate bilbies were made in 1982, but the concept really took off when major chocolate retailer Darrell Lea became involved in 2002. Since this time Haigh’s chocolate, Cadbury, and Pink Lady have also released delicious cocoa natives for consumption, and both Darrell Lea and Haigh’s use their profits to support bilby assistance programs, creating the “pleasant Easter sensation” that “eating a chocolate bilby is helping save the real thing” (Phillips). The Easter bilby campaign is a highly mediated approach to conservation which demonstrates the new biological principle Phil Bagust has recognised as “media selection.” Bagust observes that in our “hybridised global society” it is impossible to separate “the world of genetic selection from the world of human symbolic and material diversity as if they exist in different universes” (8). The Australian rabbit thrives in “natural selection,” having adapted to the Australian environment so successfully it threatens native species and the economic productivity of farmers. But the rabbit loses out in “cultural selection” where it is vilified in the media for its role in environmental degradation. The campaign to conserve the bilby depends, in a large part, on the rabbit’s failures in “media selection”. On Good Friday 2012 Sky News Australia quoted Mike Drinkwater of Wild Life Sydney’s support of the Easter bilby campaign: Look, the reason that we want to highlight the bilby as an iconic Easter animal is, number one, rabbits are a pest in Australia. Secondly, the bilby has these lovely endearing rabbit-like qualities. And thirdly, the bilby is a beautiful, iconic, native animal that is struggling. It is endangered so it’s important that we do all we can to support that. Drinkwater’s appeal to the bilby’s “endearing rabbit-like qualities” demonstrates that it is not the Australian rabbit’s individual embodiment which detracts from its charisma in Australian society. In this paper I will argue that the stories we tell about the European-Australian rabbit’s alienation from Indigenous country diminish the species cultural appeal. These stories are told with passionate conviction to save and protect native flora and fauna, but, too often, this promotion of the native relies on the devaluation of non-native life, to the point where individual rabbits are no longer morally considerable. Such a hierarchical approach to conservation is not only ethically problematic, but can also be ineffective because the native/invasive approach to ecology is overly simplistic. A History of Rabbit Stories In the Easter Bilby children’s book the illustrated rabbit offers to make itself disappear from the “Easter job.” The reason for this act of self-destruction is a despairing recognition of its “greedy and careless” nature, and at the same time, its selfless offer to be replaced by the ecologically conscious Bilby. In this sacrificial gesture is the implicit offering of all rabbit life for the salvation of native ecosystems and animal life. This plot line slots into a much larger series of stories we have been telling about the Australian environment. Libby Robin has observed that settler Australians have always had a love-hate relationship with the native flora and fauna of the continent (6), either devaluing native plants, animals, and ecosystems, or launching into an “overcompensating patriotic strut about the Australian biota” (Robin 9). The colonising dynamic of early Australian society was built on the devaluation of animals such as the bilby. This was reflected in the introduction of feral animals by “acclimatisation societies” and the privileging of “pets” such as cats and dogs over native animals (Plumwood). Alfred Crosby has made the persuasive argument that the invasion of Australia, and other “neo-European” countries, was, necessarily, more-than-human. In his work, Ecological Imperialism, Crosby charts the historical partnership between human European colonisers in Indigenous lands and the “grunting, lowing, neighing, crowing, chirping, snarling, buzzing, self-replicating and world-altering avalanche” (194) of introduced life that they brought with them. In response to this “guilt by association” Australians have reversed the values in the dichotomous colonial dynamic to devalue the introduced and so “empower” the colonised native. In this new “anti-colonial” story, rabbits signify a wound of colonisation which has spread across and infected indigenous country. J. M. Arthur’s (130) analysis of language in relation to colonisation highlights some of the important lexical characteristics in the rabbit stories we now tell. He observes that the rabbits’ impact on the county is described using a vocabulary of contamination: “It is a ‘menace’, a ‘problem’, an ‘infestation’, a ‘nuisance’, a ‘plague’” (170). This narrative of disease encourages a redemptive violence against living rabbits to “cure” the rabbit problem in order to atone for human mistakes in a colonial past. Redemptive Violence in Action Rabbits in Australia have been subject to a wide range of eradication measures over the past century including shooting, the destruction of burrows, poisoning, ferreting, trapping, and the well-known rabbit proof fence in Western Australia. Particularly noteworthy in this slaughter has been the introduction of biological control measures with the release of the savage and painful disease Myxomatosis in late December 1950, followed by the release of the Calicivirus (Rabbit Haemorrhage Disease, or RHD) in 1996. As recently as March 2012 the New South Wales Department of Primary Industries announced a 1.5 million dollar program called “RHD Boost” which is attempting to develop a more effective biological control agent for rabbits who have become immune to the Calicivirus. In this perverse narrative, disease becomes a cure for the rabbit’s contamination of Australian environments. Calicivirus is highly infectious, spreads rapidly, and kills rabbits en masse. Following the release of Calicivirus in 1995 it killed 10 million rabbits in eight weeks (Ponsonby Veterinary Centre). While Calicivirus appears to be more humane than the earlier biological control, Myxomatosis, there are indications that it causes rabbits pain and stress. Victims are described as becoming very quiet, refusing to eat, straining for breath, losing coordination, becoming feverish, and excreting bloody nasal discharge (Heishman, 2011). Post-mortem dissection generally reveals a “pale and mottled liver, many small streaks or blotches on the lungs and an enlarged spleen... small thrombi or blood clots” (Coman 173). Public criticism of the cruel methods involved in killing rabbits is often assuaged with appeals to the greater good of the ecosystem. The Anti-Rabbit research foundation state on their Website, Rabbit-Free Australia, that: though killing rabbits may sound inhumane, wild rabbits are affecting the survival of native Australian plants and animals. It is our responsibility to control them. We brought the European rabbit here in the first place — they are an invasive pest. This assumption of personal and communal responsibility for the rabbit “problem” has a fundamental blind-spot. Arthur (130) observes that the progress of rabbits across the continent is often described as though they form a coordinated army: The rabbit extends its ‘dominion’, ‘dispossesses’ the indigenous bilby, causes sheep runs to be ‘abandoned’ and country ‘forfeited’, leaving the land in ‘ecological tatters’. While this language of battle pervades rabbit stories, humans rarely refer to themselves as invaders into Aboriginal lands. Arthur notes that, by taking responsibility for the rabbit’s introduction and eradication, the coloniser assumes an indigenous status as they defend the country against the exotic invader (134). The apprehension of moral responsibility can, in this sense, be understood as the assumption of settler indigeneity. This does not negate the fact that assuming human responsibility for the native environment can be an act of genuine care. In a country scarred by a history of ecocide, movements like the Easter Bilby campaign seek to rectify the negligent mistakes of the past. The problem is that reactive responses to the colonial devaluation of native life can be unproductive because they preserve the basic structure of the native/invasive dichotomy by simplistically reversing its values, and fail to respond to more complex ecological contexts and requirements (Plumwood). This is also socially problematic because the native/invasive divide of nonhuman life overlays more complex human politics of colonisation in Australia. The Native/Invasive Dualism The bilby is currently listed as an “endangered” species in Queensland and as “vulnerable” nationally. Bilbies once inhabited 70% of the Australian landscape, but now inhabit less than 15% of the country (Save the Bilby Fund). This dramatic reduction in bilby numbers has multiple causes, but the European rabbit has played a significant role in threatening the bilby species by competing for burrows and food. Other threats come from the predation of introduced species, such as feral cats and foxes, and the impact of farmed introduced species, such as sheep and cattle, which also destroy bilby habitats. Because the rabbit directly competes with the bilby for food and shelter in the Australian environment, the bilby can be classed as the underdog native, appealing to that larger Australian story about “the fair go”. It seems that the Easter bilby campaign is intended to level out the threat posed by the highly successful and adaptive rabbit through promoting the bilby in the “cultural selection” stakes. This involves encouraging bilby-love, while actively discouraging love and care for the introduced rabbits which threaten the bilby’s survival. On the Rabbit Free Australia Website, the campaign rationale to replace the Easter bunny with the Easter bilby claims that: Very young children are indoctrinated with the concept that bunnies are nice soft fluffy creatures whereas in reality they are Australia’s greatest environmental feral pest and cause enormous damage to the arid zone. In this statement the lived corporeal presence of individual rabbits is denied as the “soft, fluffy” body disappears behind the environmentally problematic species’ behaviour. The assertion that children are “indoctrinated” to find rabbits love-able, and that this conflicts with the “reality” of the rabbit as environmentally destructive, denies the complexity of the living animal and the multiple possible responses to it. That children find rabbits “fluffy” is not the result of pro-rabbit propaganda, but because rabbits are fluffy! That Rabbit Free Australia could construe this to be some kind of elaborate falsehood demonstrates the disappearance of the individual rabbit in the native/invasive tale of colonisation. Rabbit-Free Australia seeks to eradicate the animal not only from Australian ecosystems, but from the hearts and minds of children who are told to replace the rabbit with the more fitting native bilby. There is no acceptance here of the rabbit as a complex animal that evokes ambivalent responses, being both worthy of moral consideration, care and love, and also an introduced and environmentally destructive species. The native/invasive dualism is a subject of sustained critique in environmental philosophy because it depends on a disjunctive temporal division drawn at the point of European settlement—1788. Environmental philosopher Thom van Dooren points out that the divide between animals who belong and animals who should be eradicated is “fundamentally premised on the reification of a specific historical moment that ignores the changing and dynamic nature of ecologies” (11). Mark Davis et al. explain that the practical value of the native/invasive dichotomy in conservation programs is seriously diminished and in some cases is becoming counterproductive (153). They note that “classifying biota according to their adherence to cultural standards of belonging, citizenship, fair play and morality does not advance our understanding of ecology” (153). Instead, they promote a more inclusive approach to conservation which accepts non-native species as part of Australia’s “new nature” (Low). Recent research into wildlife conservation indicates a striking lack of evidence for the case that pest control protects native diversity (see Bergstromn et al., Davis et al., Ewel & Putz, Reddiex & Forsyth). The problematic justification of “killing for conservation” becomes untenable when conservation outcomes are fundamentally uncertain. The mass slaughter which rabbits have been subjected to in Australia has been enacted with the goal of fostering life. This pursuit of creation through destruction, of re-birth through violent death, enacts a disturbing twist where death comes to signal the presence of life. This means, perversely, that a rabbit’s dead body becomes a valuable sign of environmental health. Conservation researchers Ben Reddiex and David M. Forsyth observe that this leads to a situation where environmental managers are “more interested in estimating how many pests they killed rather than the status of biodiversity they claimed to be able to protect” (715). What Other Stories Can We Tell about the Rabbit? With an ecological narrative that is failing, producing damage and death instead of fostering love and life, we are left with the question—what other stories can we tell about the place of the European rabbit in the Australian environment? How can the meaning ecologies of media and culture work in harmony with an ecological consciousness that promotes compassion for nonhuman life? Ignoring the native/invasive distinction entirely is deeply problematic because it registers the ecological history of Australia as continuity, and fails to acknowledge the colonising impact of European settlement on the environment. At the same time, continually reinforcing that divide through pro-invasive or pro-native stories drastically simplifies complex and interconnected ecological systems. Instead of the unproductive native/invasive dualism, ecologists and philosophers alike are suggesting “reconciliatory” approaches to the inhabitants of our shared environments which emphasise ecology as relational rather than classificatory. Evolutionary ecologist Scott P. Carroll uses the term “conciliation biology” as an alternative to invasion biology which focuses on the eradication of invasive species. “Conciliation biology recognises that many non-native species are permanent, that outcomes of native-nonnative interactions will vary depending on the scale of assessment and the values assigned to the biotic system, and that many non-native species will perform positive functions in one or more contexts” (186). This hospitable approach aligns with what Michael Rosensweig has termed “reconciliation ecology”—the modification and diversification of anthropogenic habitats to harbour a wider variety of species (201). Professor of Ecology and Evolutionary Biology Mark Bekoff encourages a “compassionate conservation” which avoids the “numbers game” of species thinking where certain taxonomies are valued above others and promotes approaches which “respect all life; treat individuals with respect and dignity; and tread lightly when stepping into the lives of animals”(24). In a similar vein environmental philosopher Deborah Bird Rose offers the term “Eco-reconciliation”, to describe a mode of “living generously with others, singing up relationships so that we all flourish” (Wild Dog 59). It may be that the rabbit cannot live in harmony with the bilby, and in this situation I am unsure of what a conciliation approach to ecology might look like in terms of managing both of these competing species. But I am sure what it should not look like if we are to promote approaches to ecology and conservation which avoid the simplistic dualism of native/invasive. The devaluation of rabbit life to the point of moral inconsiderability is fundamentally unethical. By classifying certain lives as “inappropriate,” and therefore expendable, the process of rabbit slaughter is simply too easy. The idea that the rabbit should disappear is disturbing in its abstract approach to these living, sentient creatures who share with us both place and history. A dynamic understanding of ecology dissipates the notion of a whole or static “nature.” This means that there can be no simple or comprehensive directives for how humans should interact with their environments. One of the most insidious aspects of the native/invasive divide is the way it makes violent death appear inevitable, as though rabbits must be culled. This obscures the many complex and contingent choices which determine the fate of nonhuman life. Understanding the dynamism of ecology requires an acceptance that nature does not provide simple prescriptive responses to problems, and instead “people are forced to choose the kind of environment they want” (189) and then take actions to engender it. This involves difficult decisions, one of which is culling to maintain rabbit numbers and facilitate environmental resilience. Living within a world of “discordant harmonies”, as Daniel Botkin evocatively describes it, environmental decisions are necessarily complex. The entanglement of ecological systems demands that we reject simplistic dualisms which offer illusory absolution from the consequences of the difficult choices humans make about life, ecologies, and how to manage them. Ecological Remembrance The vision of a rabbit-free Australia is unrealistic. As organisation like the Anti-Rabbit Research Foundation pursue this future ideal, they eradicate rabbits from the present, and seek to remove them from the past by replacing them culturally with the more suitable bilby. Culled rabbits lie rotting en masse in fields, food for no one, and even their cultural impact in human society is sought to be annihilated and replaced with more appropriate native creatures. The rabbits’ deaths do not turn back to life in transformative and regenerative processes that are ecological and cultural, but rather that death becomes “an event with no future” (Rose, Wild Dog 25). This is true oblivion, as the rabbit is entirely removed from the world. In this paper I have made a case for the importance of stories in ecology. I have argued that the kinds of stories we tell about rabbits determines how we treat them, and so have positioned stories as an essential part of an ecological system which takes “cultural selection” seriously. In keeping with this emphasis on story I offer to the conciliation push in ecological thinking the term “ecological remembrance” to capture an ethic of sharing time while sharing space. This spatio-temporal hospitality is focused on maintaining heterogeneous memories and histories of all beings who have impacted on the environment. In Deborah Bird Rose’s terms this is a “recuperative work” which commits to direct dialogical engagement with the past that is embedded in the present (Wild Country 23). In this sense it is a form of recuperation that promotes temporal and ecological continuity. Eco-remembrance aligns with dynamic understandings of ecology because it is counter-linear. Instead of approaching the past as a static idyll, preserved and archived, ecological remembrance celebrates the past as an ongoing, affective presence which is lived and performed. Ecological remembrance, applied to the European rabbit in Australia, would involve rejecting attempts to extricate the rabbit from Australian environments and cultures. It would seek acceptance of the rabbit as part of Australia’s “new nature” (Low), and aim for recognition of the rabbit’s impact on human society as part of dynamic multi-species ecologies. In this sense ecological remembrance of the rabbit directly opposes the goal of the Foundation for Rabbit Free Australia to eradicate the European rabbit from Australian environment and culture. On the Rabbit Free Australia website, the section on biological controls states that “the point is not how many rabbits are killed, but how many are left behind”. The implication is that the millions upon millions of rabbit lives extinguished have vanished from the earth, and need not be remembered or considered. However, as Deborah Rose argues, “all deaths matter” (Wild Dog 21) and “no death is a mere death” (Wild Dog 22). Every single rabbit is an individual being with its own unique life. To deny this is tantamount to claiming that each rabbit that dies from shooting or poisoning is the same rabbit dying again and again. Rose has written that “death makes claims upon all of us” (Wild Dog 19). These are claims of ethics and compassion, a claim that “we look into the eyes of the dying and not flinch, that we reach out to hold and to help” (Wild Dog 20). This claim is a duty of remembrance, a duty to “bear witness” (Wiesel 160) to life and death. The Nobel Peace Prize winning author, Elie Wiesel, argued that memory is a reconciliatory force that creates bonds as mass annihilation seeks to destroy them. Memory ensures that no life becomes truly life-less as it wrests the victims of mass slaughter from “oblivion” and allows the dead to “vanquish death” (21). 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