Journal articles on the topic 'Pre-predator model'

In this paper, we discuss a model of two-space food chain consisting of the population of ecology of foxes (the predator) and rabbits (prey) in Awash National park, Ethiopia. The study is based on formulation of a mathematical model to study the dynamics of the population densities and analyzing the stability of equilibrium points of the prey-predator model. The aim of this model is to explore the behavior of a simple model by considering a population of foxes, and rabbits. This model is constituted by a system of nonlinear decoupled ordinary differential equations. By using perturbed method, we identify the nature of the system at each equilibrium point. The stability analysis of a prey-predator model is discussed with numerical simulations.

Conway's classic game of life is a two-dimensional cellular automaton in which each cell is alive or dead and evolves according to simple rules that depend solely on the number of live cells in its immediate neighborhood. The emergence of complex multi-cellular objects provides a fascinating vehicle for exploration. A variant of the classic game of life is presented, the generalized semi-classical game of life, in which each cell contains a qubit that evolves by repeated application of birth, death, and survival operators. Species are characterized by just two parameters: a preferred neighborhood liveness representing the tendency to herd and a resilience parameter representing species' vulnerability to environmental changes. This generalized model provides the opportunity to model the fortune of species and to compare to available data. The model is shown to mimic environmental catastrophes and is illustrated by the model's prediction of a return to the pre-hunting level of the global whale population by 2140. A student-designed predator–prey model is shown to qualitatively describe the fate of strongly- and weakly coupled predator–prey systems (snowshoe hare/lynx and rabbit/fox, respectively) and sudden and slow predatory impact (dodo and diprotodon, respectively).

Some defended prey animals can switch on their normally hidden aposematic signals. This switching may occur in reaction to predators’ approach (pre-attack signals) or attack (post-attack signals). Switchable aposematism has been relatively poorly studied, but we can expect that it might bring a variety of benefits to an aposmetic organism. First, the switching could startle the predators (deimatism). Second, it could facilitate aversive learning. Third, it could minimize exposure or energetic expense, as the signal can be switched off. These potential benefits might offset costs of developing, maintaining and utilizing the switchable traits. Here we focused on the third benefit of switchability, the cost-saving aspect, and developed an individual-based computer simulation of predators and prey. In 88,128 model runs, we observed evolution of permanent, pre-attack, or post-attack aposematic signals of varying strength. We found that, in general, the pre-attack switchable aposematism may require moderate predator learning speed, high basal detectability, and moderate to high signal cost. On the other hand, the post-attack signals may arise under slow predator learning, low basal detectability and high signal cost. When predator population turnover is fast, it may lead to evolution of post-attack aposematic signals that are not conforming to the above tendency. We also suggest that a high switching cost may exert different selection pressure on the pre-attack than the post-attack switchable strategies. To our knowledge, these are the first theoretical attempts to systematically explore the evolution of switchable aposematism relative to permanent aposematism in defended prey. Our simulation model is capable of addressing additional questions beyond the scope of this article, and we open the simulation software, program manual and source code for free public use.

CAD system (computer aided diagnosis) assists medical experts in NHL (Non Hodgkin's lymphoma) diagnosis for making better decisions. In the case of NHL diagnosis, the manual analysis required more time. A few issues with the current methods included low accuracy, increased computational complexity, low dependability, increased feature dimensionality, and increased time consumption due to inadequate hyperparameter optimization. Hence, this work presents a CAD approach that ensures efficient and accurate diagnosis of NHL at the beginning stage. The proposed work has the different stages like pre-processing, optimal feature extraction and classification. The input images are resized and the features from the images are extracted and classified. This process is carried out by the DL (deep learning) model DenseNet121 with IPO (improved predator optimization) approach. The hyperparameters like batch size, neurons in the dense layer and learning rate are optimized by the IPO which minimizes the over-fitting and complexity. The analysis is demonstrated on the malignant lymphoma classification dataset and achieved a better accuracy of 98.6%.

Captive breeding programs are an important pillar in biodiversity conservation, aiming to prevent the extinction of threatened species. However, the establishment of self-sustaining populations in the wild through the release of captive-bred animals is often hampered by a high mortality upon release. In this study, we investigated how a 2-week confinement period within a large field enclosure affected the anti-predator behaviour of ‘naive’ captive-bred hamsters and how potential modifications persisted over time. During three consecutive tests, hamsters were confronted with a moving predator model (a red fox mount, Vulpes vulpes) and their behaviour was filmed. After the initial round of confrontation with the predator model, one group of hamsters (field group) was released into a field enclosure protected from predators, while the other group (control) remained in their individual laboratory cages. After 2 weeks, hamsters from the field group were recaptured and individuals of both groups underwent a second confrontation test. A total of 1 month after their return from the field enclosure, field hamsters were subjected to a last confrontation test. Video analysis, investigating four behavioural variables, revealed that field hamsters significantly modified their behavioural response following the 2 weeks confinement in the enclosure, while this was not the case for control hamsters. In addition, most behavioural modifications in field hamsters persisted over 1 month, while others started to revert. We suggest that an appropriate pre-release period inside a field enclosure will enable naive (captive-bred) hamsters to develop an adequate anti-predator behaviour that will increase their immediate survival probability upon release into the wild. We believe that such measure will be of great importance for hamster conservation programs.

Accurate streamflow prediction is significant when developing water resource management and planning, forecasting floods, and mitigating flood damage. This research developed a novel methodology that involves data pre-processing and an artificial neural network (ANN) optimised with the coefficient-based particle swarm optimisation and chaotic gravitational search algorithm (CPSOCGSA-ANN) to forecast the monthly water streamflow. The monthly streamflow data of the Tigris River at Amarah City, Iraq, from 2010 to 2020, were used to build and evaluate the suggested methodology. The performance of CPSOCGSA was compared with the slim mold algorithm (SMA) and marine predator algorithm (MPA). The principal findings of this research are that data pre-processing effectively improves the data quality and determines the optimum predictor scenario. The hybrid CPSOCGSA-ANN outperformed both the SMA-ANN and MPA-ANN algorithms. The suggested methodology offered accurate results with a coefficient of determination of 0.91, and 100% of the data were scattered between the agreement limits of the Bland–Altman diagram. The research results represent a further step toward developing hybrid models in hydrology applications.

Technology has revolutionized the way transactions are carried out in economies across the world. India too has witnessed the introduction of numerous modes of electronic payment in the past couple of decades, including e-banking services, National Electronic Fund Transfer (NEFT), Real Time Gross Settlement (RTGS) and most recently the Unified Payments Interface (UPI). While other payment mechanisms have witnessed a gradual and consistent increase in the volume of transactions, UPI has witnessed an exponential increase in usage and is almost on par with pre-existing technologies in the volume of transactions. This study aims to employ a modified Lotka-Volterra (LV) equations (also known as the Predator-Prey Model) to study the competition among different payment mechanisms. The market share of each platform is estimated using the LV equations and combined with the estimates of the total market size obtained using the Auto-Regressive Integrated Moving Average (ARIMA) technique. The result of the model predicts that UPI will eventually overtake the conventional digital payment mechanism in terms of market share as well as volume. Thus, the model indicates a scenario where both payment mechanisms would coexist with UPI being the dominant (or more preferred) mode of payment.

Early detection of breast lesions and distinguishing between malignant and benign lesions are critical for breast cancer (BC) prognosis. Breast ultrasonography (BU) is an important radiological imaging modality for the diagnosis of BC. This study proposes a BU image-based framework for the diagnosis of BC in women. Various pre-trained networks are used to extract the deep features of the BU images. Ten wrapper-based optimization algorithms, including the marine predator algorithm, generalized normal distribution optimization, slime mold algorithm, equilibrium optimizer (EO), manta-ray foraging optimization, atom search optimization, Harris hawks optimization, Henry gas solubility optimization, path finder algorithm, and poor and rich optimization, were employed to compute the optimal subset of deep features using a support vector machine classifier. Furthermore, a network selection algorithm was employed to determine the best pre-trained network. An online BU dataset was used to test the proposed framework. After comprehensive testing and analysis, it was found that the EO algorithm produced the highest classification rate for each pre-trained model. It produced the highest classification accuracy of 96.79%, and it was trained using only a deep feature vector with a size of 562 in the ResNet-50 model. Similarly, the Inception-ResNet-v2 had the second highest classification accuracy of 96.15% using the EO algorithm. Moreover, the results of the proposed framework are compared with those in the literature.

Researchers in behavioral neuroscience commonly observe the behavior of animal subjects in the presence of two alternative stimuli. However, this type of binary choice introduces a potential confound related to side biases. Understanding whether subjects exhibit this bias, and the origin of it (pre-existent or acquired throughout the experimental sessions), is particularly important to interpreting the results. Here, we tested the hypothesis according to which brain lateralization may influence the emergence of side biases in a well-known model of neuroscience, the zebrafish. As a measure of lateralization, individuals were observed in their spontaneous tendencies to monitor a potential predator with either the left or the right eye. Subjects also underwent an operant conditioning task requiring discrimination between two colors placed on the left–right axis. Although the low performance exhibited in the operant conditioning task prevents firm conclusions from being drawn, a positive correlation was found between the direction of lateralization and the tendency to select the stimulus presented on one specific side (e.g., right). The choice for this preferred side did not change throughout the experimental sessions, meaning that this side bias was not the result of the prolonged training. Overall, our study calls for a wider investigation of pre-existing lateralization biases in animal models to set up methodological counterstrategies to test individuals that do not properly work in a binary choice task with stimuli arranged on the left–right axis.

This study delves into the intricate dynamics of sustainable fisheries through the lens of mathematical modeling, specifically employing the Lotka-Volterra equa-tions. The Lotka-Volterra equations, originally conceived to understand predator-prey interactions, offer a potent framework to model and predict fish population dynamics within aquatic ecosystems. The aim of this research is to demonstrate the applicability and efficacy of the Lotka-Volterra equations in understanding the delicate balance of fish populations and aiding sustainable fisheries man-agement. Through this mathematical approach, we seek to provide a structured methodology and present results that showcase the potential of this model in pre-dicting and managing fish populations. In our analysis, we adjust the parameters of the Lotka-Volterra equations to simulate various scenarios, enabling a compre-hensive understanding of sustainable fishing practices. Our findings underscore the significance of mathematical models, particularly the Lotka-Volterra equa-tions, in informing strategies to maintain fish populations in a sustainable and ecologically balanced manner, thereby ensuring the longevity of marine ecosys-tems and the fisheries that rely upon them.Keywords: Runge-Kutta, Two-step, Exponentially-fitted, Periodic; Oscillatory;

This investigation showed an ontogenetic shift in the palatability of Bufo marinus tadpoles by measuring consumption of tadpoles at three different developmental stages (newly hatched, intermediate and pre- metamorphic) by an Australian predatory fish, Lates calcarifer (barramundi). A known-palatable tadpole, Limnodynastes ornatus, was used as the control. B. marinus tadpoles at all developmental stages were unpalatable relative to a palatable alternative, with the later stages being the least palatable. Choice experiments further demonstrated that L. calcarifer were able to recognise and choose L. ornatus tadpoles in preference to those of B. marinus. Our experiments demonstrate that at all stages of development, B. marinus tadpoles were unpalatable to L. calcarifer. Contrary to the model proposed by Brodie and Formanowicz (1987), our results suggest an ontogenetic shift in palatability of B. marinus tadpoles to a vertebrate fish predator, with the later stages being less palatable.

Diabetic retinopathy (DR) is a severe complication of diabetes. It affects a large portion of the population of the Kingdom of Saudi Arabia. Existing systems assist clinicians in treating DR patients. However, these systems entail significantly high computational costs. In addition, dataset imbalances may lead existing DR detection systems to produce false positive outcomes. Therefore, the author intended to develop a lightweight deep-learning (DL)-based DR-severity grading system that could be used with limited computational resources. The proposed model followed an image pre-processing approach to overcome the noise and artifacts found in fundus images. A feature extraction process using the You Only Look Once (Yolo) V7 technique was suggested. It was used to provide feature sets. The author employed a tailored quantum marine predator algorithm (QMPA) for selecting appropriate features. A hyperparameter-optimized MobileNet V3 model was utilized for predicting severity levels using images. The author generalized the proposed model using the APTOS and EyePacs datasets. The APTOS dataset contained 5590 fundus images, whereas the EyePacs dataset included 35,100 images. The outcome of the comparative analysis revealed that the proposed model achieved an accuracy of 98.0 and 98.4 and an F1 Score of 93.7 and 93.1 in the APTOS and EyePacs datasets, respectively. In terms of computational complexity, the proposed DR model required fewer parameters, fewer floating-point operations (FLOPs), a lower learning rate, and less training time to learn the key patterns of the fundus images. The lightweight nature of the proposed model can allow healthcare centers to serve patients in remote locations. The proposed model can be implemented as a mobile application to support clinicians in treating DR patients. In the future, the author will focus on improving the proposed model’s efficiency to detect DR from low-quality fundus images.

Abstract Gestures, particularly pointing, are regarded as important pre-speech acts. Intentional and referential pointing has been shown previously in humans and apes but not in songbirds, although some avian species show cognitive abilities rivaling those of apes, and their brain structures and functions show putative preconditions for referential gestural signaling (i.e. mirror neurons, links of vocal learning nuclei to discrete brain areas active during limb and body movements). The results reported are based on trials testing predator detection and responses to a taxidermic model of a wedge-tailed eagle by Australian magpies Gymnorhina tibicen. Magpies were subjected to three conditions of finding this model in their territory (open, sheltered and hidden). In the sheltered and hidden conditions, the discoverer simultaneously engaged in alarm calls and beak pointing, a behavior that has not been described previously. Other group members at once assembled and, after watching the first bird, adopted the same posture by pointing to the location of the intruder. The question is whether beak and body movements orienting towards important stimuli or events are instances of arousal, imitation or intentional communication. The latter presupposes that onlookers interpret the signal and respond by altering their own behavior appropriate to the original stimulus and not merely by imitating the first signaler. Evidence presented here indicates that the act of pointing may well be a complex cognitive behavior, i.e., an intentional and referential signal, showing that pointing is not limited to having hands and arms.

In large-scale multi-agent systems, the large number of agents and complex game relationship cause great difficulty for policy learning. Therefore, simplifying the learning process is an important research issue. In many multi-agent systems, the interactions between agents often happen locally, which means that agents neither need to coordinate with all other agents nor need to coordinate with others all the time. Traditional methods attempt to use pre-defined rules to capture the interaction relationship between agents. However, the methods cannot be directly used in a large-scale environment due to the difficulty of transforming the complex interactions between agents into rules. In this paper, we model the relationship between agents by a complete graph and propose a novel game abstraction mechanism based on two-stage attention network (G2ANet), which can indicate whether there is an interaction between two agents and the importance of the interaction. We integrate this detection mechanism into graph neural network-based multi-agent reinforcement learning for conducting game abstraction and propose two novel learning algorithms GA-Comm and GA-AC. We conduct experiments in Traffic Junction and Predator-Prey. The results indicate that the proposed methods can simplify the learning process and meanwhile get better asymptotic performance compared with state-of-the-art algorithms.

Ectotherm locomotion is restricted by low temperatures, and many species, such as some flying insects, need to achieve thermal thresholds before taking off. Body size influences heat exchange between an animal and the environment. Therefore, larger animals have higher thermal inertia, and necessarily spend more time in pre-flight warming up, a critical period when they remain exposed and more susceptible to predators. Thus, one could expect larger animals, along their evolutionary history, to have developed a more diversified repertoire of defensive behaviors when compared to their smaller counterparts. Moths are an interesting model for testing this hypothesis, as they exhibit considerable variation in body size and many species present pre-flight warming up by muscle shivering, an evidence of thermal restriction on locomotion. I registered the responses of 76 moths immediately after simulating the attack of a predator and then associated behavioral response to body size. I conducted the experiments at 20 and 25ºC to check for possible thermal restrictions on behavior, and identified animals to the family level to check for the effects of a common phylogenetic history. When disturbed at 25ºC, smaller moths tend to fly, while larger ones tend to run. At 20ºC almost all moths ran, including the smaller ones, indicating a possible thermal restriction on flight. Corroborating the proposed hypothesis, a more diversified repertoire of defensive behaviors was registered among larger moths. An alternative interpretation would be that common behaviors among related moths could be explained by common phylogenetic histories. However, two facts support the physiological restriction hypothesis: (1) the analysis within Sphingidae and Geometridae (not closely related families) showed similar results to those of the overall analysis, and (2) a more diverse repertoire of defensive behaviors was associated to the lower, and therefore more restrictive to locomotion, temperature (20ºC).

Translocations of threatened species play an increasingly important role in conservation management. However, few studies have examined what effects, if any, the translocation process itself (i.e. catching, handling, confining, transferring and releasing an animal into an unfamiliar environment) has on subsequent breeding success. Takahe Porphyrio hochstetteri living on offshore “predator-free” islands in New Zealand are a model system for examining such effects because pre-breeding birds have been frequently translocated between established island populations before they pair up and breed at 2-3 years of age. We postulated that “translocated” breeders (i.e. breeders that had been raised on another island) would delay first breeding attempts and/or have lower reproductive success compared with “resident” birds (i.e. bred on the same island that they were raised). The results indicated that translocated birds did not delay breeding and had similar mean hatching and fledging success as resident pairs in their first breeding season and subsequent seasons combined. The results suggest that at least for large or long-lived birds such as Takahe, the effects of any stress from the translocation itself, or the release into an unfamiliar environment, might be either short-lived or not significant enough to hinder subsequent breeding success. We recommend that further research be carried out on other species to determine the baseline effects, if any, of translocations, so that they can be taken into account when considering other determinants of translocation success such as habitat suitability, number of individuals and timing of releases.

Abstract Röckmann, C., Dickey-Collas, M., Payne, M. R., and van Hal, R. 2011. Realized habitats of early-stage North Sea herring: looking for signals of environmental change. – ICES Journal of Marine Science, 68: . Realized habitats of North Sea herring for two larval and two juvenile stages were estimated over the past 30 years, using abundances from surveys tied to modelled estimates of temperature and salinity. Newly hatched larvae (NHL) were found mainly in water masses of 9–11°C, pre-metamorphosis larvae (PML) around 5–6°C, juveniles aged 0 in summer around 13–14°C, and juveniles aged 1 in winter around 4–5°C. The median salinity in which the NHL were distributed was 34.4–35.0 and 33.7–33.9, respectively, for PML and juveniles. Interannual variations in temperature and geographic variables in the North Sea were compared with the time-series of realized habitats. The realized temperature habitats of the NHL did not change over time, but the habitat of juveniles in summer may be associated with higher temperatures. Juveniles aged 1 in winter are found in waters colder than the average for the North Sea, a result also reflected in their geographic shift east into shallower water. The results suggest that juveniles could be limited by temperature, but may also track changes in food or predator distribution, and/or internal population dynamics. Time-series analysis of realized salinity habitats was not possible with the available data because of differences between model outputs.

(Uploaded by Plazi for the Bat Literature Project) The simple auditory system of noctuoid moths has long captured the moth. At this point, the firing of the A1 cell been a model for anti-predator studies in neuroethology, reduces to a non-bursting pattern with longer inter-spike although these ears have rarely been experimentally periods, suggesting that the moth may no longer express stimulated by the sounds they would encounter from the erratic flight used to escape very close bats. This may naturally attacking bats. We exposed the ears of five be simply due to the absence of selection pressure on noctuoid moth species to the pre-recorded echolocation moths for auditory tracking of bat echolocation calls calls of an attacking bat (Eptesicus fuscus) to observe the beyond this point. Alternatively, the reduced firing may be acoustic encoding of the receptors at this critical time in due to the acoustic characteristics of attack calls in the their defensive behaviour. The B cell is a non-tympanal terminal phase and an acoustic maneuver used by the bat receptor common to all moths that has been suggested to to facilitate its capture of the moth. Although the role of respond to sound, but we found no evidence of this and less sensitive A2 cell remains uncertain in the evasive flight suggest that its acoustic responsiveness is an artifact responses of moths it may act as a trigger in eliciting arising from its proprioceptive function. The A1 cell, the sound production, a close-range anti-bat behaviour in the most sensitive tympanal receptor in noctuid and arctiid tiger moth, Cycnia tenera.

(Uploaded by Plazi for the Bat Literature Project) The simple auditory system of noctuoid moths has long captured the moth. At this point, the firing of the A1 cell been a model for anti-predator studies in neuroethology, reduces to a non-bursting pattern with longer inter-spike although these ears have rarely been experimentally periods, suggesting that the moth may no longer express stimulated by the sounds they would encounter from the erratic flight used to escape very close bats. This may naturally attacking bats. We exposed the ears of five be simply due to the absence of selection pressure on noctuoid moth species to the pre-recorded echolocation moths for auditory tracking of bat echolocation calls calls of an attacking bat (Eptesicus fuscus) to observe the beyond this point. Alternatively, the reduced firing may be acoustic encoding of the receptors at this critical time in due to the acoustic characteristics of attack calls in the their defensive behaviour. The B cell is a non-tympanal terminal phase and an acoustic maneuver used by the bat receptor common to all moths that has been suggested to to facilitate its capture of the moth. Although the role of respond to sound, but we found no evidence of this and less sensitive A2 cell remains uncertain in the evasive flight suggest that its acoustic responsiveness is an artifact responses of moths it may act as a trigger in eliciting arising from its proprioceptive function. The A1 cell, the sound production, a close-range anti-bat behaviour in the most sensitive tympanal receptor in noctuid and arctiid tiger moth, Cycnia tenera.

Purpose The purpose of this paper is to address both the evolutionary and control aspects associated with the management of artificial superintelligence. Through empirical analysis, the authors examine the diffusion pattern of those high technologies that can be considered as forerunners to the adoption of artificial superintelligence (ASI). Design/methodology/approach The evolutionary perspective is divided into three parts, based on major developments in this area, namely, robotics, automation and artificial intelligence (AI). The authors then provide several dynamic models of the possible future evolution of superintelligence. These include diffusion modeling, predator–prey models and hostility models. The problem of control in superintelligence is reviewed next, where the authors discuss Asimov’s Laws and IEEE initiative. The authors also provide an empirical analysis of the application of diffusion modeling to three technologies from the industries of manufacturing, communication and energy, which can be considered as potential precursors to the evolution of the field of ASI. The authors conclude with a case study illustrating emerging solutions in the form of long-term social experiments to address the problem of control in superintelligence. Findings The results from the empirical analysis of the manufacturing, communication and energy sectors suggest that the technology diffusion model fits well with the data of robotics, telecom and solar installations till date. The results suggest a gradual diffusion process, like any other high technology. Thus, there appears to be no threat of “existential catastrophe” (Bostrom, 2014). The case study indicates that any future threat can be pre-empted by some long-term social measures. Originality/value This paper contributes to the emerging stream of artificial superintelligence. As humanity comes closer to grappling with the important question of the management and control of this technology for the future, it is important that modeling efforts be made to understand the extant perspective of the development of the high-technology diffusion. Presently, there are relatively few such efforts available in the literature.

The recovery of whale populations from centuries of exploitation will have important management and ecological implications due to greater exposure to anthropogenic activities and increasing prey consumption. Here, a Bayesian population model integrates catch data, estimates of abundance, and information on genetics and biology to assess the recovery of western South Atlantic (WSA) humpback whales ( Megaptera novaeangliae ). Modelling scenarios evaluated the sensitivity of model outputs resulting from the use of different data, different model assumptions and uncertainty in catch allocation and in accounting for whales killed but not landed. A long period of exploitation drove WSA humpback whales to the brink of extinction. They declined from nearly 27 000 (95% PI = 22 800–33 000) individuals in 1830 to only 450 (95% PI = 200–1400) whales in the mid-1950s. Protection led to a strong recovery and the current population is estimated to be at 93% (95% PI = 73–100%) of its pre-exploitation size. The recovery of WSA humpback whales may result in large removals of their primary prey, the Antarctic krill ( Euphausia superba ), and has the potential to modify the community structure in their feeding grounds. Continued monitoring is needed to understand how these whales will respond to modern threats and to climate-driven changes to their habitats.

Sensory bias, a predisposition towards certain signals, has been implicated in the origin of mate preferences in some species. A risk associated with these biases is that they can be co-opted by predators as sensory lures. Here we propose that the orange spots on the brown pincers of a diurnal, predatory species of prawn function as lures for Trinidadian guppies, which have a sensory bias for orange. We exposed female guppies to (i) a life-like model of this Trinidadian prawn with orange, green or no spots on the pincers or (ii) a live, novel (non-Trinidadian) crustacean (crayfish), also with spotted pincers. First, we provide evidence that guppies sympatric with the prawn recognized our model as a potential predator. Next, we found that guppies spent more time in the dangerous head region of the model prawn with orange-spotted pincers compared with unspotted pincers. Finally, we show that allopatric, but not sympatric, guppies spent more time in the vicinity of the head of a live crayfish when orange spots were added to its pincers than when brown spots were added. Our results suggest that the orange spots on prawn pincers can act as a sensory lure.

To date, discrete event stochastic simulations of large scale biological reaction systems are extremely compute-intensive and time-consuming. Besides, it has been widely accepted that spatial factor plays a critical role in the dynamics of most biological reaction systems. The NSM (the Next Sub-Volume Method), a spatial variation of the Gillespie’s stochastic simulation algorithm (SSA), has been proposed for spatially stochastic simulation of those systems. While being able to explore high degree of parallelism in systems, NSM is inherently sequential, which still suffers from the problem of low simulation speed. Fine-grained parallel execution is an elegant way to speed up sequential simulations. Thus, based on the discrete event simulation framework JAMES II, we design and implement a PDES (Parallel Discrete Event Simulation) TW (time warp) simulator to enable the fine-grained parallel execution of spatial stochastic simulations of biological reaction systems using the ANSM (the Abstract NSM), a parallel variation of the NSM. The simulation results of classical Lotka-Volterra biological reaction system show that our time warp simulator obtains remarkable parallel speed-up against sequential execution of the NSM.I.IntroductionThe goal of Systems biology is to obtain system-level investigations of the structure and behavior of biological reaction systems by integrating biology with system theory, mathematics and computer science [1][3], since the isolated knowledge of parts can not explain the dynamics of a whole system. As the complement of “wet-lab” experiments, stochastic simulation, being called the “dry-computational” experiment, plays a more and more important role in computing systems biology [2]. Among many methods explored in systems biology, discrete event stochastic simulation is of greatly importance [4][5][6], since a great number of researches have present that stochasticity or “noise” have a crucial effect on the dynamics of small population biological reaction systems [4][7]. Furthermore, recent research shows that the stochasticity is not only important in biological reaction systems with small population but also in some moderate/large population systems [7].To date, Gillespie’s SSA [8] is widely considered to be the most accurate way to capture the dynamics of biological reaction systems instead of traditional mathematical method [5][9]. However, SSA-based stochastic simulation is confronted with two main challenges: Firstly, this type of simulation is extremely time-consuming, since when the types of species and the number of reactions in the biological system are large, SSA requires a huge amount of steps to sample these reactions; Secondly, the assumption that the systems are spatially homogeneous or well-stirred is hardly met in most real biological systems and spatial factors play a key role in the behaviors of most real biological systems [19][20][21][22][23][24]. The next sub-volume method (NSM) [18], presents us an elegant way to access the special problem via domain partition. To our disappointment, sequential stochastic simulation with the NSM is still very time-consuming, and additionally introduced diffusion among neighbor sub-volumes makes things worse. Whereas, the NSM explores a very high degree of parallelism among sub-volumes, and parallelization has been widely accepted as the most meaningful way to tackle the performance bottleneck of sequential simulations [26][27]. Thus, adapting parallel discrete event simulation (PDES) techniques to discrete event stochastic simulation would be particularly promising. Although there are a few attempts have been conducted [29][30][31], research in this filed is still in its infancy and many issues are in need of further discussion. The next section of the paper presents the background and related work in this domain. In section III, we give the details of design and implementation of model interfaces of LP paradigm and the time warp simulator based on the discrete event simulation framework JAMES II; the benchmark model and experiment results are shown in Section IV; in the last section, we conclude the paper with some future work.II. Background and Related WorkA. Parallel Discrete Event Simulation (PDES)The notion Logical Process (LP) is introduced to PDES as the abstract of the physical process [26], where a system consisting of many physical processes is usually modeled by a set of LP. LP is regarded as the smallest unit that can be executed in PDES and each LP holds a sub-partition of the whole system’s state variables as its private ones. When a LP processes an event, it can only modify the state variables of its own. If one LP needs to modify one of its neighbors’ state variables, it has to schedule an event to the target neighbor. That is to say event message exchanging is the only way that LPs interact with each other. Because of the data dependences or interactions among LPs, synchronization protocols have to be introduced to PDES to guarantee the so-called local causality constraint (LCC) [26]. By now, there are a larger number of synchronization algorithms have been proposed, e.g. the null-message [26], the time warp (TW) [32], breath time warp (BTW) [33] and etc. According to whether can events of LPs be processed optimistically, they are generally divided into two types: conservative algorithms and optimistic algorithms. However, Dematté and Mazza have theoretically pointed out the disadvantages of pure conservative parallel simulation for biochemical reaction systems [31]. B. NSM and ANSM The NSM is a spatial variation of Gillespie’ SSA, which integrates the direct method (DM) [8] with the next reaction method (NRM) [25]. The NSM presents us a pretty good way to tackle the aspect of space in biological systems by partitioning a spatially inhomogeneous system into many much more smaller “homogeneous” ones, which can be simulated by SSA separately. However, the NSM is inherently combined with the sequential semantics, and all sub-volumes share one common data structure for events or messages. Thus, directly parallelization of the NSM may be confronted with the so-called boundary problem and high costs of synchronously accessing the common data structure [29]. In order to obtain higher efficiency of parallel simulation, parallelization of NSM has to firstly free the NSM from the sequential semantics and secondly partition the shared data structure into many “parallel” ones. One of these is the abstract next sub-volume method (ANSM) [30]. In the ANSM, each sub-volume is modeled by a logical process (LP) based on the LP paradigm of PDES, where each LP held its own event queue and state variables (see Fig. 1). In addition, the so-called retraction mechanism was introduced in the ANSM too (see algorithm 1). Besides, based on the ANSM, Wang etc. [30] have experimentally tested the performance of several PDES algorithms in the platform called YH-SUPE [27]. However, their platform is designed for general simulation applications, thus it would sacrifice some performance for being not able to take into account the characteristics of biological reaction systems. Using the similar ideas of the ANSM, Dematté and Mazza have designed and realized an optimistic simulator. However, they processed events in time-stepped manner, which would lose a specific degree of precisions compared with the discrete event manner, and it is very hard to transfer a time-stepped simulation to a discrete event one. In addition, Jeschke etc.[29] have designed and implemented a dynamic time-window simulator to execution the NSM in parallel on the grid computing environment, however, they paid main attention on the analysis of communication costs and determining a better size of the time-window.Fig. 1: the variations from SSA to NSM and from NSM to ANSMC. JAMES II JAMES II is an open source discrete event simulation experiment framework developed by the University of Rostock in Germany. It focuses on high flexibility and scalability [11][13]. Based on the plug-in scheme [12], each function of JAMES II is defined as a specific plug-in type, and all plug-in types and plug-ins are declared in XML-files [13]. Combined with the factory method pattern JAMES II innovatively split up the model and simulator, which makes JAMES II is very flexible to add and reuse both of models and simulators. In addition, JAMES II supports various types of modelling formalisms, e.g. cellular automata, discrete event system specification (DEVS), SpacePi, StochasticPi and etc.[14]. Besides, a well-defined simulator selection mechanism is designed and developed in JAMES II, which can not only automatically choose the proper simulators according to the modeling formalism but also pick out a specific simulator from a serious of simulators supporting the same modeling formalism according to the user settings [15].III. The Model Interface and SimulatorAs we have mentioned in section II (part C), model and simulator are split up into two separate parts. Thus, in this section, we introduce the designation and implementation of model interface of LP paradigm and more importantly the time warp simulator.A. The Mod Interface of LP ParadigmJAMES II provides abstract model interfaces for different modeling formalism, based on which Wang etc. have designed and implemented model interface of LP paradigm[16]. However, this interface is not scalable well for parallel and distributed simulation of larger scale systems. In our implementation, we accommodate the interface to the situation of parallel and distributed situations. Firstly, the neighbor LP’s reference is replaced by its name in LP’s neighbor queue, because it is improper even dangerous that a local LP hold the references of other LPs in remote memory space. In addition, (pseudo-)random number plays a crucial role to obtain valid and meaningful results in stochastic simulations. However, it is still a very challenge work to find a good random number generator (RNG) [34]. Thus, in order to focus on our problems, we introduce one of the uniform RNGs of JAMES II to this model interface, where each LP holds a private RNG so that random number streams of different LPs can be independent stochastically. B. The Time Warp SimulatorBased on the simulator interface provided by JAMES II, we design and implement the time warp simulator, which contains the (master-)simulator, (LP-)simulator. The simulator works strictly as master/worker(s) paradigm for fine-grained parallel and distributed stochastic simulations. Communication costs are crucial to the performance of a fine-grained parallel and distributed simulation. Based on the Java remote method invocation (RMI) mechanism, P2P (peer-to-peer) communication is implemented among all (master-and LP-)simulators, where a simulator holds all the proxies of targeted ones that work on remote workers. One of the advantages of this communication approach is that PDES codes can be transferred to various hardwire environment, such as Clusters, Grids and distributed computing environment, with only a little modification; The other is that RMI mechanism is easy to realized and independent to any other non-Java libraries. Since the straggler event problem, states have to be saved to rollback events that are pre-processed optimistically. Each time being modified, the state is cloned to a queue by Java clone mechanism. Problem of this copy state saving approach is that it would cause loads of memory space. However, the problem can be made up by a condign GVT calculating mechanism. GVT reduction scheme also has a significant impact on the performance of parallel simulators, since it marks the highest time boundary of events that can be committed so that memories of fossils (processed events and states) less than GVT can be reallocated. GVT calculating is a very knotty for the notorious simultaneous reporting problem and transient messages problem. According to our problem, another GVT algorithm, called Twice Notification (TN-GVT) (see algorithm 2), is contributed to this already rich repository instead of implementing one of GVT algorithms in reference [26] and [28].This algorithm looks like the synchronous algorithm described in reference [26] (pp. 114), however, they are essentially different from each other. This algorithm has never stopped the simulators from processing events when GVT reduction, while algorithm in reference [26] blocks all simulators for GVT calculating. As for the transient message problem, it can be neglect in our implementation, because RMI based remote communication approach is synchronized, that means a simulator will not go on its processing until the remote the massage get to its destination. And because of this, the high-costs message acknowledgement, prevalent over many classical asynchronous GVT algorithms, is not needed anymore too, which should be constructive to the whole performance of the time warp simulator.IV. Benchmark Model and Experiment ResultsA. The Lotka-Volterra Predator-prey SystemIn our experiment, the spatial version of Lotka-Volterra predator-prey system is introduced as the benchmark model (see Fig. 2). We choose the system for two considerations: 1) this system is a classical experimental model that has been used in many related researches [8][30][31], so it is credible and the simulation results are comparable; 2) it is simple but helpful enough to test the issues we are interested in. The space of predator-prey System is partitioned into a2D NXNgrid, whereNdenotes the edge size of the grid. Initially the population of the Grass, Preys and Predators are set to 1000 in each single sub-volume (LP). In Fig. 2,r1,r2,r3stand for the reaction constants of the reaction 1, 2 and 3 respectively. We usedGrass,dPreyanddPredatorto stand for the diffusion rate of Grass, Prey and Predator separately. Being similar to reference [8], we also take the assumption that the population of the grass remains stable, and thusdGrassis set to zero.R1:Grass + Prey ->2Prey(1)R2:Predator +Prey -> 2Predator(2)R3:Predator -> NULL(3)r1=0.01; r2=0.01; r3=10(4)dGrass=0.0;dPrey=2.5;dPredato=5.0(5)Fig. 2: predator-prey systemB. Experiment ResultsThe simulation runs have been executed on a Linux Cluster with 40 computing nodes. Each computing node is equipped with two 64bit 2.53 GHz Intel Xeon QuadCore Processors with 24GB RAM, and nodes are interconnected with Gigabit Ethernet connection. The operating system is Kylin Server 3.5, with kernel 2.6.18. Experiments have been conducted on the benchmark model of different size of mode to investigate the execution time and speedup of the time warp simulator. As shown in Fig. 3, the execution time of simulation on single processor with 8 cores is compared. The result shows that it will take more wall clock time to simulate much larger scale systems for the same simulation time. This testifies the fact that larger scale systems will leads to more events in the same time interval. More importantly, the blue line shows that the sequential simulation performance declines very fast when the mode scale becomes large. The bottleneck of sequential simulator is due to the costs of accessing a long event queue to choose the next events. Besides, from the comparison between group 1 and group 2 in this experiment, we could also conclude that high diffusion rate increased the simulation time greatly both in sequential and parallel simulations. This is because LP paradigm has to split diffusion into two processes (diffusion (in) and diffusion (out) event) for two interactive LPs involved in diffusion and high diffusion rate will lead to high proportional of diffusion to reaction. In the second step shown in Fig. 4, the relationship between the speedups from time warp of two different model sizes and the number of work cores involved are demonstrated. The speedup is calculated against the sequential execution of the spatial reaction-diffusion systems model with the same model size and parameters using NSM.Fig. 4 shows the comparison of speedup of time warp on a64X64grid and a100X100grid. In the case of a64X64grid, under the condition that only one node is used, the lowest speedup (a little bigger than 1) is achieved when two cores involved, and the highest speedup (about 6) is achieved when 8 cores involved. The influence of the number of cores used in parallel simulation is investigated. In most cases, large number of cores could bring in considerable improvements in the performance of parallel simulation. Also, compared with the two results in Fig. 4, the simulation of larger model achieves better speedup. Combined with time tests (Fig. 3), we find that sequential simulator’s performance declines sharply when the model scale becomes very large, which makes the time warp simulator get better speed-up correspondingly.Fig. 3: Execution time (wall clock time) of Seq. and time warp with respect to different model sizes (N=32, 64, 100, and 128) and model parameters based on single computing node with 8 cores. Results of the test are grouped by the diffusion rates (Group 1: Sequential 1 and Time Warp 1. dPrey=2.5, dPredator=5.0; Group 2: dPrey=0.25, dPredator=0.5, Sequential 2 and Time Warp 2).Fig. 4: Speedup of time warp with respect to the number of work cores and the model size (N=64 and 100). Work cores are chose from one computing node. Diffusion rates are dPrey=2.5, dPredator=5.0 and dGrass=0.0.V. Conclusion and Future WorkIn this paper, a time warp simulator based on the discrete event simulation framework JAMES II is designed and implemented for fine-grained parallel and distributed discrete event spatial stochastic simulation of biological reaction systems. Several challenges have been overcome, such as state saving, roll back and especially GVT reduction in parallel execution of simulations. The Lotka-Volterra Predator-Prey system is chosen as the benchmark model to test the performance of our time warp simulator and the best experiment results show that it can obtain about 6 times of speed-up against the sequential simulation. The domain this paper concerns with is in the infancy, many interesting issues are worthy of further investigated, e.g. there are many excellent PDES optimistic synchronization algorithms (e.g. the BTW) as well. Next step, we would like to fill some of them into JAMES II. In addition, Gillespie approximation methods (tau-leap[10] etc.) sacrifice some degree of precision for higher simulation speed, but still could not address the aspect of space of biological reaction systems. The combination of spatial element and approximation methods would be very interesting and promising; however, the parallel execution of tau-leap methods should have to overcome many obstacles on the road ahead.AcknowledgmentThis work is supported by the National Natural Science Foundation of China (NSF) Grant (No.60773019) and the Ph.D. Programs Foundation of Ministry of Education of China (No. 200899980004). The authors would like to show their great gratitude to Dr. Jan Himmelspach and Dr. Roland Ewald at the University of Rostock, Germany for their invaluable advice and kindly help with JAMES II.ReferencesH. Kitano, "Computational systems biology." Nature, vol. 420, no. 6912, pp. 206-210, November 2002.H. Kitano, "Systems biology: a brief overview." 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Cancer is one of the leading significant causes of illness and chronic disease worldwide. Skin cancer, particularly melanoma, is becoming a severe health problem due to its rising prevalence. The considerable death rate linked with melanoma requires early detection to receive immediate and successful treatment. Lesion detection and classification are more challenging due to many forms of artifacts such as hairs, noise, and irregularity of lesion shape, color, irrelevant features, and textures. In this work, we proposed a deep-learning architecture for classifying multiclass skin cancer and melanoma detection. The proposed architecture consists of four core steps: image preprocessing, feature extraction and fusion, feature selection, and classification. A novel contrast enhancement technique is proposed based on the image luminance information. After that, two pre-trained deep models, DarkNet-53 and DensNet-201, are modified in terms of a residual block at the end and trained through transfer learning. In the learning process, the Genetic algorithm is applied to select hyperparameters. The resultant features are fused using a two-step approach named serial-harmonic mean. This step increases the accuracy of the correct classification, but some irrelevant information is also observed. Therefore, an algorithm is developed to select the best features called marine predator optimization (MPA) controlled Reyni Entropy. The selected features are finally classified using machine learning classifiers for the final classification. Two datasets, ISIC2018 and ISIC2019, have been selected for the experimental process. On these datasets, the obtained maximum accuracy of 85.4% and 98.80%, respectively. To prove the effectiveness of the proposed methods, a detailed comparison is conducted with several recent techniques and shows the proposed framework outperforms.

This paper is meant to study the apocalyptic scenario of the at the perspectives of the Great Acceleration. the apocalyptic scenario is not a pure imagination of the literature works. Instead, scientific evidences are in favour of dramatic change in the climatic conditions related to the climax of Man actions. the modelling of the future climate leads to horrible situations including intolerable temperatures, dryness, tornadoes, and noticeable sear level rise evading coastal regions. Going far from these scientific claims, Homo Sapiens Sapiens extended his imagination through the Climate-Fiction (cli-fi) to propose a dramatic end. Climate Fiction is developed into a recording machine containing every kind of fictions that depict environmental condition events and has consequently lost its true significance.
 Introduction
 The Great Acceleration may be considered as the Late Anthropocene in which Man actions reached their climax to lead to dramatic climatic changes paving the way for a possible apocalyptic scenario threatening the existence of the humanity. So, the apocalyptic scenario is not a pure imagination of the literature works. Instead, many scientific arguments especially related to climate change are in favour of the apocalypse1. As a matter of fact, the modelling of the future climate leads to horrible situations including intolerable temperatures (In 06/07/2021, Kuwait recorded the highest temperature of 53.2 °C), dryness, tornadoes, and noticeable sear level rise evading coastal regions. These conditions taking place during the Great Acceleration would have direct repercussions on the human species. Considering that the apocalyptic extinction had really caused the disappearance of many stronger species including dinosaurs, Homo Sapiens Sapiens extended his imagination though the Climate-Fiction (cli-fi) to propose a dramatic end due to severe climate conditions intolerable by the humankind. The mass extinction of animal species has occurred several times over the geological ages. Researchers have a poor understanding of the causes and processes of these major crises1. Nonetheless, whatever the cause of extinction, the apocalyptic scenario has always been present in the geological history. For example, dinosaurs extinction either by asteroids impact or climate changes could by no means denies the apocalyptic aspect2.At the same time as them, many animal and plant species became extinct, from marine or flying reptiles to marine plankton. This biological crisis of sixty-five million years ago is not the only one that the biosphere has suffered. It was preceded and followed by other crises which caused the extinction or the rarefaction of animal species. So, it is undeniable that many animal groups have disappeared. It is even on the changes of fauna that the geologists of the last century have based themselves to establish the scale of geological times, scale which is still used. But it is no less certain that the extinction processes, extremely complex, are far from being understood. We must first agree on the meaning of the word "extinction", namely on the apocalyptic aspect of the concept. It is quite understood that, without disappearances, the evolution of species could not have followed its course. Being aware that the apocalyptic extinction had massacred stronger species that had dominated the planet, Homo Sapiens Sapiens has been aware that the possibility of apocalyptic end at the perspective of the Anthropocene (i.e., Great Acceleration) could not be excluded. This conviction is motivated by the progressive defaunation in some regions3and the appearance of alien species in others related to change of mineralogy and geochemistry4 leading to a climate change during the Anthropocene. These scientific claims fed the vast imagination about climate change to set the so-called cli-fi. The concept of the Anthropocene is the new geological era which begins when the Man actions have reached a sufficient power to modify the geological processes and climatic cycles of the planet5. The Anthropocene by no means excludes the possibility of an apocalyptic horizon, namely in the perspectives of the Great Acceleration. On the contrary, two scenarios do indeed seem to dispute the future of the Anthropocene, with a dramatic cross-charge. The stories of the end of the world are as old as it is, as the world is the origin of these stories. However, these stories of the apocalypse have evolved over time and, since the beginning of the 19th century, they have been nourished particularly by science and its advances. These fictions have sometimes tried to pass themselves off as science. This is the current vogue, called collapsology6. This end is more than likely cli-fi driven7and it may cause the extinction of the many species including the Homo Sapiens Sapiens. In this vein, Anthropocene defaunation has become an ultimate reality8. More than one in eight birds, more than one in five mammals, more than one in four coniferous species, one in three amphibians are threatened. The hypothesis of a hierarchy within the living is induced by the error of believing that evolution goes from the simplest to the most sophisticated, from the inevitably stupid inferior to the superior endowed with an intelligence giving prerogative to all powers. Evolution goes in all directions and pursues no goal except the extension of life on Earth. Evolution certainly does not lead from bacteria to humans, preferably male and white. Our species is only a carrier of the DNA that precedes us and that will survive us. Until we show a deep respect for the biosphere particularly, and our planet in general, we will not become much, we will remain a predator among other predators, the fiercest of predators, the almighty craftsman of the Anthropocene. To be in the depths of our humanity, somehow giving back to the biosphere what we have taken from it seems obvious. To stop the sixth extinction of species, we must condemn our anthropocentrism and the anthropization of the territories that goes with it. The other forms of life also need to keep their ecological niches. According to the first, humanity seems at first to withdraw from the limits of the planet and ultimately succumb to them, with a loss of dramatic meaning. According to the second, from collapse to collapse, it is perhaps another humanity, having overcome its demons, that could come. Climate fiction is a literary sub-genre dealing with the theme of climate change, including global warming. The term appears to have been first used in 2008 by blogger and writer Dan Bloom. In October 2013, Angela Evancie, in a review of the novel Odds against Tomorrow, by Nathaniel Rich, wonders if climate change has created a new literary genre. Scientific basis of the apocalyptic scenario in the perspective of the Anthropocene
 Global warming
 All temperature indices are in favour of a global warming (Fig.1). According to the different scenarios of the IPCC9, the temperatures of the globe could increase by 2 °C to 5 °C by 2100. But some scientists warn about a possible runaway of the warming which can reach more than 3 °C. Thus, the average temperature on the surface of the globe has already increased by more than 1.1 °C since the pre-industrial era. The rise in average temperatures at the surface of the globe is the first expected and observed consequence of massive greenhouse gas emissions. However, meteorological surveys record positive temperature anomalies which are confirmed from year to year compared to the temperatures recorded since the middle of the 19th century. Climatologists point out that the past 30 years have seen the highest temperatures in the Northern Hemisphere for over 1,400 years. Several climatic centres around the world record, synthesize and follow the evolution of temperatures on Earth. Since the beginning of the 20th century (1906-2005), the average temperature at the surface of the globe has increased by 0.74 °C, but this progression has not been continuous since 1976, the increase has clearly accelerated, reaching 0.19 °C per decade according to model predictions. Despite the decline in solar activity, the period 1997-2006 is marked by an average positive anomaly of 0.53 °C in the northern hemisphere and 0.27 °C in the southern hemisphere, still compared to the normal calculated for 1961-1990. The ten hottest years on record are all after 1997. Worse, 14 of the 15 hottest years are in the 21st century, which has barely started. Thus, 2016 is the hottest year, followed closely by 2015, 2014 and 2010. The temperature of tropical waters increased by 1.2 °C during the 20th century (compared to 0.5 °C on average for the oceans), causing coral reefs to bleach in 1997.
 In 1998, the period of Fort El Niño, the prolonged warming of the water has destroyed half of the coral reefs of the Indian Ocean. In addition, the temperature in the tropics of the five ocean basins, where cyclones form, increased by 0.5 °C from 1970 to 2004, and powerful cyclones appeared in the North Atlantic in 2005, while they were more numerous in other parts of the world. Recently, mountains of studies focused on the possible scenario of climate change and the potential worldwide repercussions including hell temperatures and apocalyptic extreme events10 , 11, 12.
 Melting of continental glaciers
 As a direct result of the global warming, melting of continental glaciers has been recently noticed13. There are approximately 198,000 mountain glaciers in the world; they cover an area of approximately 726,000 km2. If they all melted, the sea level would rise by about 40 cm. Since the late 1960s, global snow cover has declined by around 10 to 15%. Winter cold spells in much of the northern half of the northern hemisphere are two weeks shorter than 100 years ago. Glaciers of mountains have been declining all over the world by an average of 50 m per decade for 150 years. However, they are also subject to strong multi-temporal variations which make forecasts on this point difficult according to some specialists. In the Alps, glaciers have been losing 1 meter per year for 30 years. Polar glaciers like those of Spitsbergen (about a hundred km from the North Pole) have been retreating since 1880, releasing large quantities of water. The Arctic has lost about 10% of its permanent ice cover every ten years since 1980. In this region, average temperatures have increased at twice the rate of elsewhere in the world in recent decades. The melting of the Arctic Sea ice has resulted in a loss of 15% of its surface area and 40% of its thickness since 1979. The record for melting arctic sea ice was set in 2017. All models predict the disappearance of the Arctic Sea ice in summer within a few decades, which will not be without consequences for the climate in Europe. The summer melting of arctic sea ice accelerated far beyond climate model predictions. Added to its direct repercussions of coastal regions flooding, melting of continental ice leads to radical climatic modifications in favour of the apocalyptic scenario.
 
 Fig.1 Evolution of temperature anomaly from 1880 to 2020: the apocalyptic scenario
 
 Sea level rise
 As a direct result of the melting of continental glaciers, sea level rise has been worldwide recorded14 ,15. The average level of the oceans has risen by 22 cm since 1880 and 2 cm since the year 2000 because of the melting of the glaciers but also with the thermal expansion of the water. In the 20th century, the sea level rose by around 2 mm per year. From 1990 to 2017, it reached the relatively constant rate of just over 3mm per year. Several sources contributed to sea level increase including thermal expansion of water (42%), melting of continental glaciers (21%), melting Greenland glaciers (15%) and melting Antarctic glaciers (8%). Since 2003, there has always been a rapid rise (around 3.3 mm / year) in sea level, but the contribution of thermal expansion has decreased (0.4 mm / year) while the melting of the polar caps and continental glaciers accelerates. Since most of the world’s population is living on coastal regions, sea level rise represents a real threat for the humanity, not excluding the apocalyptic scenario.
 Multiplication of extreme phenomena and climatic anomalies
 On a human scale, an average of 200 million people is affected by natural disasters each year and approximately 70,000 perish from them. Indeed, as evidenced by the annual reviews of disasters and climatic anomalies, we are witnessing significant warning signs. It is worth noting that these observations are dependent on meteorological survey systems that exist only in a limited number of countries with statistics that rarely go back beyond a century or a century and a half. In addition, scientists are struggling to represent the climatic variations of the last two thousand years which could serve as a reference in the projections. Therefore, the exceptional nature of this information must be qualified a little. Indeed, it is still difficult to know the return periods of climatic disasters in each region. But over the last century, the climate system has gone wild. Indeed, everything suggests that the climate is racing. Indeed, extreme events and disasters have become more frequent. For instance, less than 50 significant events were recorded per year over the period 1970-1985, while there have been around 120 events recorded since 1995.
 Drought has long been one of the most worrying environmental issues. But while African countries have been the main affected so far, the whole world is now facing increasingly frequent and prolonged droughts. Chile, India, Australia, United States, France and even Russia are all regions of the world suffering from the acceleration of the global drought. Droughts are slowly evolving natural hazards that can last from a few months to several decades and affect larger or smaller areas, whether they are small watersheds or areas of hundreds of thousands of square kilometres. In addition to their direct effects on water resources, agriculture and ecosystems, droughts can cause fires or heat waves. They also promote the proliferation of invasive species, creating environments with multiple risks, worsening the consequences on ecosystems and societies, and increasing their vulnerability. Although these are natural phenomena, there is a growing understanding of how humans have amplified the severity and impacts of droughts, both on the environment and on people. We influence meteorological droughts through our action on climate change, and we influence hydrological droughts through our management of water circulation and water processes at the local scale, for example by diverting rivers or modifying land use. During the Anthropocene (the present period when humans exert a dominant influence on climate and environment), droughts are closely linked to human activities, cultures, and responses. From this scientific overview, it may be concluded apocalyptic scenario is not only a literature genre inspired from the pure imagination. Instead, many scientific arguments are in favour of this dramatic destiny of Homo Sapiens Sapiens.
 
 Fig.2. Sea level rise from 1880 to 2020: a possible apocalyptic scenario (www.globalchange.gov, 2021)
 
 Apocalyptic genre in recent writing
 As the original landmark of apocalyptic writing, we must place the destruction of the Temple of Jerusalem in 587 BC and the Exile in Babylon. Occasion of a religious and cultural crossing with imprescriptible effects, the Exile brought about a true rebirth, characterized by the maintenance of the essential ethical, even cultural, of a national religion, that of Moses, kept as pure as possible on a foreign land and by the reinterpretation of this fundamental heritage by the archaic return of what was very old, both national traditions and neighbouring cultures. More precisely, it was the place and time for the rehabilitation of cultures and the melting pot for recasting ancient myths. This vast infatuation with Antiquity, remarkable even in the vocabulary used, was not limited to Israel: it even largely reflected a general trend. The long period that preceded throughout the 7th century BC and until 587, like that prior to the edict of Cyrus in 538 BC, was that of restorations and rebirths, of returns to distant sources and cultural crossings. In the biblical literature of this period, one is struck by the almost systematic link between, on the one hand, a very sustained mythical reinvestment even in form and, on the other, the frequent use of biblical archaisms. The example of Shadday, a word firmly rooted in the Semites of the Northwest and epithet of El in the oldest layers of the books of Genesis and Exodus, is most eloquent. This term reappears precisely at the time of the Exile as a designation of the divinity of the Patriarchs and of the God of Israel; Daily, ecological catastrophes now describe the normal state of societies exposed to "risks", in the sense that Ulrich Beck gives to this term: "the risk society is a society of catastrophe. The state of emergency threatens to become a normal state there1”. Now, the "threat" has become clearer, and catastrophic "exceptions" are proliferating as quickly as species are disappearing and climate change is accelerating. The relationship that we have with this worrying reality, to say the least, is twofold: on the one hand, we know very well what is happening to us; on the other hand, we fail to draw the appropriate theoretical and political consequences. This ecological duplicity is at the heart of what has come to be called the “Anthropocene”, a term coined at the dawn of the 21st century by Eugene Stoermer (an environmentalist) and Paul Crutzen (a specialist in the chemistry of the atmosphere) in order to describe an age when humanity would have become a "major geological force" capable of disrupting the climate and changing the terrestrial landscape from top to bottom. If the term “Anthropocene” takes note of human responsibility for climate change, this responsibility is immediately attributed to overpowering: strong as we are, we have “involuntarily” changed the climate for at least two hundred and fifty years. Therefore, let us deliberately change the face of the Earth, if necessary, install a solar shield in space. Recognition and denial fuel the signifying machine of the Anthropocene. And it is precisely what structures eco-apocalyptic cinema that this article aims to study. By "eco-apocalyptic cinema", we first mean a cinematographic sub-genre: eco-apocalyptic and post-eco-apocalyptic films base the possibility (or reality) of the end of the world on environmental grounds and not, for example, on damage caused by the possible collision of planet Earth with a comet. Post-apocalyptic science fiction (sometimes abbreviated as "post-apo" or "post-nuke") is a sub-genre of science fiction that depicts life after a disaster that destroyed civilization: nuclear war, collision with a meteorite, epidemic, economic or energy crisis, pandemic, alien invasion.
 Conclusion
 Climate and politics have been linked together since Aristotle. With Montesquieu, Ibn Khaldûn or Watsuji, a certain climatic determinism is attributed to the character of a nation. The break with modernity made the climate an object of scientific knowledge which, in the twentieth century, made it possible to document, despite the controversies, the climatic changes linked to industrialization. Both endanger the survival of human beings and ecosystems. Climate ethics are therefore looking for a new relationship with the biosphere or Gaia. For some, with the absence of political agreements, it is the beginning of inevitable catastrophes. For others, the Anthropocene, which henceforth merges human history with natural history, opens onto technical action. The debate between climate determinism and human freedom is revived. The reference to the biblical Apocalypse was present in the thinking of thinkers like Günther Anders, Karl Jaspers or Hans Jonas: the era of the atomic bomb would mark an entry into the time of the end, a time marked by the unprecedented human possibility of 'total war and annihilation of mankind. The Apocalypse will be very relevant in describing the chaos to come if our societies continue their mad race described as extra-activist, productivist and consumerist. In dialogue with different theologians and philosophers (such as Jacques Ellul), it is possible to unveil some spiritual, ethical, and political resources that the Apocalypse offers for thinking about History and human engagement in the Anthropocene. What can a theology of collapse mean at a time when negative signs and dead ends in the human situation multiply? What then is the place of man and of the cosmos in the Apocalypse according to Saint John? Could the end of history be a collapse? How can we live in the time we have left before the disaster? Answers to such questions remain unknown and no scientist can predict the trajectory of this Great Acceleration taking place at the Late Anthropocene.
 When science cannot give answers, Man tries to infer his destiny for the legend, religion and the fiction. Climate Fiction is developed into a recording machine containing every kind of fictions that depict environmental condition events and has consequently lost its true significance. Aware of the prospect of ecological collapse additionally as our apparent inability to avert it, we tend to face geology changes of forceful proportions that severely challenge our ability to imagine the implications. Climate fiction ought to be considered an important supplement to climate science, as a result, climate fiction makes visible and conceivable future modes of existence inside worlds not solely deemed seemingly by science, however that area unit scientifically anticipated. Hence, this chapter, as part of the book itself, aims to contribute to studies of ecocriticism, the environmental humanities, and literary and culture studies.
 
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Seven spot ladybird beetle, (Coccinella septempunctata) is a widely distributed natural enemy of soft-bodied insect pests especially aphids worldwide. Both the adult and larvae of this coccinellid beetle are voracious feeders and serve as a commercially available biological control agent around the globe. Different techniques are adopted to enhance the mass rearing and storage of this natural enemy by taking advantage of its natural ability to withstand under extremely low temperatures and entering diapause under unfavorable low temperature conditions. The key objective of this study was to develop a cost effective technique for enhancing the storage life and predatory potential of the larvae of C. septempunctata through cold storage in conjunction with the use of nuclear techniques, gamma radiations. Results showed that the host eating potential of larvae was enhanced as the cold storage duration was increased. Gamma irradiation further enhanced the feeding potential of larvae that were kept under cold storage. Different irradiation doses also affected the development time of C. septempuntata larvae significantly. Without cold storage, the lower radiation doses (10 and 25 GY) prolonged the developmental time as compared to un-irradiated larvae. Furthermore, the higher dose of radiation (50GY) increased the developmental time after removal from cold storage. This study first time paves the way to use radiation in conjunction with cold storage as an effective technique in implementation of different biological control approaches as a part of any IPM programs.Key wordGamma irradiations; cold storage, Coccinella septempunctata larvae; predatory potential; integrated pest management programme.INTRODUCTIONNuclear techniques such as gamma radiations have a vast application in different programmes of biological control including continuous supply of sterilized host and improved rearing techniques (Greany and Carpenter, 2000; Cai et al., 2017). Similarly irradiation can be used for sentinel-host eggs and larvae for monitoring survival and distribution of parasitoids (Jordão-paranhos et al., 2003; Hendrichs et al., 2009; Tunçbilek et al., 2009; Zapater et al., 2009; Van Lenteren, 2012). Also, at the production level, such technique may facilitate the management of host rearing, improve quality and expedite transport of product (Fatima et al., 2009; Hamed et al., 2009; Wang et al., 2009). Gamma irradiations can also be used to stop insect’s development to enhance host suitability for their use in different mass rearing programs (Celmer-Warda, 2004; Hendrichs et al., 2009; Seth et al., 2009). Development and survival of all insects have a direct connection with temperatures which in turn affect the physical, functional and behavioral adaptations (Ramløy, 2000). Many insects living in moderate regions can survive at low temperature by process of diapause. A temperature between 0 to 10oC may cause some insects to become sluggish and they only become active when the temperature is suitable. Such insects show greater adaptations to flexible temperature regimes for better survival. Many studies have reported this concept of cold-hardiness in insects in general (Bale, 2002; Danks, 2006) and specifically in coccinellid beetles over past years (Watanabe, 2002; Koch et al., 2004; Pervez and Omkar, 2006; Labrie et al., 2008; Berkvens et al., 2010). Using this cold hardiness phenomenon, many coccinellids have been studied for the effect of cold storage such as Coccinella undecimpunctata (Abdel‐Salam and Abdel‐Baky, 2000), Coleomegilla maculata (Gagné and Coderre, 2001) and Harmonia axyridis (Watanabe, 2002). This natural phenomenon, therefore, can be a helpful tool in developing low temperature stockpiling for improving mass-rearing procedures (Mousapour et al., 2014). It may provide a significant output in terms of providing natural enemies as and when required during pest infestation peaks (Venkatesan et al., 2000). Use of irradiation in conjunction with cold storage proves to be an effective technique in implementation of different biological control approaches as a part of any IPM programme. A study reported that the pupate of house fly, Musca domestica irradiated at dose of 500 Gy and can stored up to 2 months at 6°C for future use for a parasitoid wasp Spalangia endius rearing (Zapater et al., 2009). Similarly, when irradiated at 20 GY, parasitic wasps Cotesia flavipes were stored safely up to two months without deterioration of their parasitic potential (Fatima et al., 2009). Similarly, bio-control program of sugarcane shoot borer Chilo infescatellus proved successful through the use of irradiation combined with cold storage of its egg and larval parasitoids Trichogramma chilonis and C. flavipes (Fatima et al., 2009). Less mobile life stages such as larvae are of significance in any IPM strategy because they remain on target site for more time period as compared to adults. Therefore, use of predatory larvae is very promising in different biological control approaches because of their immediate attack on pests and more resistance to unfavorable environmental conditions than delicate egg stage. In addition, with their augmentation into fields, larval stage shows their presence for longer time than adult stage and their feeding potential is also satisfactory as that of adults. For the best utilization of these predators in the field and maximum impact of 3rd and 4th larval instars on prey, we should encourage late 2nd second instar larvae of predatory beetles in the fields as these instars have more feeding capacity due to increased size and ability to handle larger preys.In spite of higher significance, there is little information available about the effect of cold storage on the survival of larval instars of different ladybird beetles and its effect on their predatory potential. Very few studies report the use of cold storage for non-diapausing larval stage like for Semiadalia undecimnotata and only one study reported the short-term storage (up to two weeks) of 2nd and 3rd instar coccinellid, C. maculate, without any loss in feeding voracity of larvae after storage (Gagné and Coderre, 2001). The survival of 3rd and 4th larval instars of C. undecimpunctata for 7 days after storage at 5oC was reported in a study but the survival rate declined after 15-60 days of storage (Abdel‐Salam and Abdel‐Baky, 2000). As C. septempunctata is considered one of the voracious predators (Afroz, 2001; Jandial and Malik, 2006; Bilashini and Singh, 2009; Xia et al., 2018) and diapause is a prominent feature of this beetle and it may undergo facultative diapause under suitable laboratory conditions (Suleman, 2015). No information is available to date about the combined effect of cold storage and irradiation on the larval instars of this species.OBJECTIVES The objective of this study was to devise a cost effective technique for the cold storage and its effect on the subsequent predatory potential of the seven spotted ladybird beetle larvae in conjunction with the use of gamma radiations. Hypothesis of the study was that an optimum length of low temperature treatment for storage purpose would not affect the predation capacity of C. septempunctata larvae and their developmental parameters including survival and pupation will remain unaffected. Furthermore, use of gamma irradiation will have some additional effects on survival and feeding capacity of irradiated C. septempunctata larvae. Such techniques can be utilized in different biocontrol programs where short term storage is required. So these larvae can be successfully imparted in different IPM programs against sucking complex of insect pests as a component of biological control strategyMATERIALS AND METHODSPlant materials: Collection and rearing of C. septempunctata: Adult C. septempunctata were collected from the wheat crop (in NIAB vicinity and farm area) in the month of March during late winter and early in spring season 2016-2017. They were kept in plastic jars and were fed with brassica aphids. Under controlled laboratory conditions (25+2oC, 16h: 8h L:D and 65+5% R.H.), eggs of C. septempuctata were obtained and after hatching, larvae were also given brassica aphids as dietary source. Larvae of second instar were selected for this experiment (as the first instar is generally very weak and vulnerable to mortality under low temperatures). As the larvae approached second instar, they were separated for the experimentation. Irradiation of larvae at different doses: Irradiation of larvae was carried out by the irradiation source 137CS at Radiation laboratory, and the larvae were then brought back to the IPM laboratory, Plant Protection Division, Nuclear Institute for Agriculture and Biology (NIAB) Faisalabad. Radiation doses of 10 GY (Grey), 25 GY and 50 GY were used to treat the second instar larvae. There were three replicates for each treatment and five larvae per replicate were used. Control treatment was left un-irradiated.Cold storage of irradiated larvae: In present work, second instar C. septempunctata larvae were studied for storage at low temperature of 8oC. The larvae were kept at 8oC for 0, I and II weeks where week 0 depicts no cold treatment and this set of larvae was left under laboratory conditions for feeding and to complete their development. For larvae that were kept under cold storage for one week at 8°C, the term week I was devised. Similarly, week II denotes the larvae that remained under cold conditions (8°C) for two continuous weeks. Larvae were removed from cold storage in their respective week i.e., after week I and week II and were left under laboratory conditions to complete their development by feeding on aphids. Data collection: For recording the predatory potential of C. septempunctata larvae, 100 aphids were provided per larva per replicate on a daily basis until pupation as this number was more than their feeding capacity to make sure that they were not starved (personal observation). Observations were recorded for survival rate, developmental time and feeding potential. Data analysis: Data were statistically analysed by Statistical Software SPSS (Version 16.0). The data were subjected to normality check through the One-sample Kolmogorov-Smirnov test. Non normal data were transformed to normal data which were then used for all parametric variance tests. One-way and two-way analyses of variance were used. For comparison between variables, LSD test at α 0.05 was applied.RESULTSFeeding potential of irradiated larvae after removal from cold storage: Results showed an increase in the feeding potential of C. septempunctata larvae with increased cold storage duration. The feeding potential was significantly higher for the larvae that spent maximum length of time (week II) under cold storage conditions followed by week I and week 0. Gamma irradiations further enhanced the feeding potential of larvae that were kept under cold storage. When larvae were irradiated at 10 GY, the eating capacity of larvae increased significantly with the duration of cold storage. Similarly, larvae that were irradiated at 25 GY, showed increase in feeding potential on aphids as the time period of cold storage increased. The feeding potential of larvae that were irradiated at 50 GY, was again significantly increased with increase of cold storage duration. When different radiation doses were compared to week 0 of storage, there was a significant difference in feeding potential and larvae irradiated at 50 GY consumed the maximum numbers of aphids when no cold storage was done followed by larvae irradiated at 10 and 25 GY. With the other treatment, where larvae were kept under cold storage for one week (week I) the larvae irradiated at 50GY again showed the highest feeding potential. The feeding potential of irradiated larvae was again significantly higher than the un-irradiated larvae that were kept for two weeks (week II) under cold storage (table 1).Two-way ANOVA was performed to check the interaction between the different radiation doses and different lengths of storage durations for feeding potential of C. septempunctata larvae on aphids. The feeding potential of larvae irradiated at different doses and subjected to variable durations of cold storage were significantly different for both the radiation doses and cold storage intervals. Furthermore, the interaction between the radiation doses and storage duration was also significant meaning that the larvae irradiated at different doses with different length of cold storage were having significant variations in feeding levels (table 2).Developmental time of irradiated larvae after removal from cold storage: Significant difference was found in the development time of the larvae of C. septempunctata when irradiated at different doses at week 0 (without cold storage). The larvae irradiated at 10 GY took the maximum time for development and with the increase in irradiation dosage, from 25 to 50 GY, the time of development was shortened. The larvae irradiated at 50 GY had the same development time as the un-irradiated ones. When, the irradiated larvae were subjected to cold storage of one week duration (week I), their development time after removal from storage condition varied significantly. The larvae irradiated at 25 GY took the maximum time for development followed by larvae irradiated at 50 GY and 10 GY. There was an indication that the development time was extended for irradiated larvae as compared to un-irradiated larvae.Results also depicted a significant difference in the time taken by irradiated larvae to complete their development after taken out from cold storage of two weeks duration (week II). As the storage time of irradiated larvae increased, the development time was prolonged. Results showed that the larvae that were irradiated at 25 and 50 GY, took the maximum time to complete their development. With the prolonged duration of cold storage up to two weeks (week II), this difference of development time was less evident at lower doses (10 GY). The larvae irradiated at 10 GY showed a significant difference in their developmental duration after being taken out of cold storage conditions of the week 0, I and II. There was no difference in the developmental duration of larvae that were un-irradiated and subjected to different regimes of storage. Un-irradiated larvae were least affected by the duration of storage. With the increase in the storage time, a decrease in the developmental time was recorded. Larvae that were irradiated at 10 GY, took the maximum period to complete their development when no cold storage was done (week 0) followed by week I and II of cold storage. When the larvae irradiated at 25 GY were compared for their development time, there was again significant difference for week 0, I and II of storage duration. Maximum time was taken by the larvae for their complete development when removed from cold storage after one week (week I). With the increase in storage duration the time taken by larvae to complete their development after removal from cold storage reduced.When the larvae were removed after different lengths of cold storage duration i.e., week 0, week I and week II, there was a significant difference in the developmental time afterwards. Results have shown that the higher dose of radiation, increased the developmental time after removal from cold storage. The larvae irradiated at 50 GY took the longest time to complete their development after removal from cold storage (week I and week II) as compared the larvae that were not kept under cold storage conditions (week 0) (table 3).Interaction between the different radiation doses and different lengths of storage durations for development time of larvae were checked by two-way ANOVA. The development time of larvae irradiated at different doses and subjected to variable durations of cold storage were significantly different for both the doses and cold storage intervals. Furthermore, the interaction between the radiation doses and storage duration was also significant meaning that the larvae irradiated at different doses with different length of cold storage were having significant variations in development times (table 4). DISCUSSIONThe present research work indicates the possibility of keeping the larval instars of C. septempunctata under cold storage conditions of 8oC for a short duration of around 14 days without affecting its further development and feeding potential. Furthermore, irradiation can enhance the feeding potential and increase the development time of larval instars. This in turn could be a useful technique in mass rearing and field release programmes for biological control through larval instars. Usually temperature range of 8-10oC is an optimal selection of low temperature for storage as reported earlier for eggs two spotted ladybird beetle, Adalia bipunctata and the eggs of C. septempunctata (Hamalainen and Markkula, 1977), Trichogramma species (Jalali and Singh, 1992) and fairyfly, Gonatocerus ashmeadi (Hymenoptra; Mymaridae) (Leopold and Chen, 2007). However, a study reported more than 80% survival rate for the coccinellid beetle, Harmonia axyridis for up to 150 days at moderately low temperature of 3-6oC (Ruan et al., 2012). So there is great flexibility in coccinellid adults and larvae for tolerating low temperature conditions. After removal from cold storage, larvae showed better feeding potential with consumption of more aphids when compared to normal larvae that were not placed under low temperature conditions. This indicates that when the adult or immature insect stages are subjected to low temperature environment, they tend to reduce their metabolic activity for keeping them alive on the reserves of their body fats and sustain themselves for a substantial length of time under such cold environment. Hereafter, the larval instars that were in cold storage were behaving as if starved for a certain length of time and showed more hunger. This behavior of improved or higher feeding potential of stored larvae has been reported previously (Chapman, 1998). Hence, the feeding potential of C. septempunctata larvae significantly increased after cold storage. Gagné and Coderre (2001) reported higher predatory efficacy in larvae of C. maculata when stored at the same temperature as in the present study i.e., 8oC. Similarly, Ruan et al. (2012) showed that the multicolored Asian ladybug, H. axyridis, when stored under cold conditions, had more eating capacity towards aphids Aphis craccivora Koch than the individuals that were not stored. Such studies indicate that the higher feeding potential in insects after being subjected to low temperature environmental conditions could be due to the maintenance of their metabolism rate to a certain level while utilizing their energy reserves to the maximum extent (Watanabe, 2002).The individuals coming out from cold storage are therefore capable of consuming more pray as they were in a condition of starvation and they have to regain their energy loss through enhanced consumption. Furthermore, the starvation in C. septempunctata has previously been reported to affect their feeding potential (Suleman et al., 2017). In the present study, the larval development was delayed after returning to normal laboratory conditions. Cold storage affects the life cycle of many insects other than coccinellids. The cold storage of green bug aphid parasitoid, Lysiphlebus testaceipes Cresson (Hymenoptra; Braconidae) mummies increased the life cycle 3-4 times. Nevertheless, in current study the development process of stored larvae resumed quickly after taking them out and larvae completed their development up to adult stage. Similar kinds of results were reported for resumption of larval development after removal from cold storage conditions. Such studies only report satisfactory survival rates and development for a short duration of cold storage but as the length of storage is increased, it could become harmful to certain insects. Gagné and Coderre (2001) reported that cold storage for longer period (three weeks) proved fatal for almost 40% of larvae of C. maculata. Furthermore, in the same study, the feeding potential of C. maculata larvae was also affected beyond two weeks of cold storage due to the loss of mobility after a long storage period. Many studies have reported that longer durations of low temperature conditions can either damage the metabolic pathways of body cells or may increase the levels of toxins within the bodies of insects. Also, low temperature exposure for longer duration may cause specific interruptions in the insect body especially neuro-hormones responsible for insect development, which could be dangerous or even life threatening.Chen et al. (2004) also reported that the biological qualities of parasitized Bemisia tabaci pupae on population quality of Encarsia formosa were affected negatively with increase in cold storage duration. Similarly, the egg hatchability of green lacewing Chrysoperla carnea Stephen was lost completely beyond 18 days of cold storage (Sohail et al., 2019). However, in the present study the cold storage was done for maximum two weeks and it is to be regarded as a short term storage hence the survival rate was satisfactory. Longer periods of cold storage for larvae are not considered safe due to their vulnerable state as compared to adults which are hardier. Also 2nd instar larvae used in the present study for cold storage for being bigger in size and physical stronger than 1st instar. Abdel‐Salam and Abdel‐Baky (2000) reported that in C. undecimpunctata the cold storage of 3rd and 4th larval instars was higher and considered safer than early larval instars. The same study showed sharp decline in survival rate after two weeks and there was no survival beyond 30-60 days of cold storage. The present study showed that short term storage of the larvae of C. septempunctata could be done without any loss of their feeding potential or development so the quality of predator remained unaffected. Similar kind of work for many other insects had been reported previously where cold storage technique proved useful without deteriorating the fitness of stored insects. For example, the flight ability of reared codling moth Cydia pomonella Linnaeus remained unaffected after removal from cold storage (Matveev et al., 2017). Moreover, a sturdy reported that pupae of a parasitoid wasp Trichogramma nerudai (Hymenoptera; Trichogrammatidae) could be safely put in cold storage for above than 50 days (Tezze and Botto, 2004). Similarly, a technique of cold storage of non-diapausing eggs of black fly Simulium ornaturm Meigen was developed at 1oC. Another study reported safe storage of a predatory bug insidious flower bug Orius insidiosus for more than 10 days at 8°C (Bueno et al., 2014).In present study without cold storage, the lower doses of 10 and 25 GY prolonged the developmental time as compared to un-irradiated larvae and higher doses of irradiations in conjunction with cold storage again significantly prolonged the developmental time of larvae when returned to the laboratory conditions. Salem et al. (2014) also reported that Gamma irradiations significantly increased the duration of developmental stages (larvae and pupae) in cutworm, Agrotis ipsilon (Hufnagel). In another study, where endoparasitic wasps Glyptapanteles liparidis were evaluated with irradiated and non-irradiated gypsy moth Lymantria dispar larvae for oviposition, it was found that non-irradiated larvae had a shorter time to reach the adult stage as compared to irradiated larvae (Novotny et al., 2003). Both for higher doses with cold storage and lower doses without cold storage extended the larval duration of C. septempunctata. In another study when the parasitoid wasp Habrobracon hebetor was irradiated at the dose of 10 GY, it resulted in prolonged longevity (Genchev et al., 2008). In the same study, when another parasitoid Ventruria canescens was irradiated at lower doses of 4GY and 3 GY, it resulted in increased emergence from the host larvae, while gamma irradiations at the dose of 1 GY and 2 GY significantly stimulated the rate of parasitism (Genchev et al., 2008). The current study also indicated higher rates of predation in the form of increased feeding potential of larvae as a result of irradiations at lower doses.CONCLUSIONThe outcome of the current study shows that storage of 2nd instar C. septempunctata at low temperature of 8oC for a short duration of about 14 days is completely safe and could have broader application in different biocontrol programs. Such flexibility in storage duration can also assist in different mass rearing techniques and commercial uses. The combination of gamma radiation with low temperature cold storage could be a useful tool in developing different biological pest management programs against sucking insect pests. Incidence of periodic occurrence of both the target insect pests with their predatory ladybird beetles in synchrony is an important aspect that could be further strengthened by cold storage techniques. Therefore, short or long term bulk cold storage of useful commercial biocontrol agents and then reactivating them at appropriate time of pest infestation is a simple but an advantageous method in mass rearing programs. Increased feeding capacity of stored larvae is another edge and hence such larvae may prove more beneficial as compared to unstored larvae. Both cold storage and improved feeding of the C. septempuctata larvae can be utilized for implementation of IPM for many sucking insect pests of various crops, fruits and vegetables. Due to some constraints this study could not be continued beyond two weeks but for future directions, higher doses and longer duration periods could further elaborate the understanding and better application of such useful techniques in future IPM programmes on a wider scale. Also, some other predatory coccinellid beetle species can be tested with similar doses and cold storage treatments to see how effective this technique is on other species as well.ACKNOWLEDGMENTS We acknowledge the Sugarcane Research and Development Board for providing a research grant (No. SRDB/P/4/16) to carry out this research work. 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The aim of this work is to investigate the numerical study of prey-predator model and give a thorough overview of the existing research. Here we see instances that involve stability analysis, phase plane, and phase portrait, among others. Furthermore, a numerical simulation is shown to illustrate the results of the prey-predator model. This is to provide light on the procedures followed in order to arrive at the conclusions. The one-prey, one-predator principle is discussed in this article from multiple theoretical perspectives. Finally, for various parameter values and time intervals, we have demonstrated the phase portraits and the dynamic behavior of the pre-predator model. Jagannath University Journal of Science, Volume 11, Number 1, June 2024, pp. 81−93

A lot of work regarding prey-predator type Lotka-Volteara model has already been done by many researchers during the last century. However, the work devoted to the concept of model related to fractional order derivatives is still inadequate. We employ Homotopy perturbation Sumudu transform method (HPSTM) to obtain the approximate solutions of these equations.
 Homotopy perturbation Sumudu transform method gives a new approach to the solution of these kind of problems. And we plot figures to illustrate this technique and it is seen that the (HPSTM) is very useful and effective method to get the approximate solutions.
 The most significant part of this study is the decay of both prey-predator populations with increase of the fractional time derivative. Another important part is increase of time taken for the meeting of prey-predator with increase of fractional time derivative. The article aims to motivate both engineers and biologists who are working on the pre-predator model to carry on further researches in this area.

Prey must balance predator avoidance with feeding, a central dilemma in prey refuge theory. Additionally, prey must assess predatory imminence—how close threats are in space and time. Predatory imminence theory classifies defensive behaviors into three defense modes: pre-encounter, post-encounter, and circa-strike, corresponding to increasing levels of threat—–suspecting, detecting, and contacting a predator. Although predatory risk often varies in spatial distribution and imminence, how these factors intersect to influence defensive behaviors is poorly understood. Integrating these factors into a naturalistic environment enables comprehensive analysis of multiple defense modes in consistent conditions. Here, we combine prey refuge and predatory imminence theories to develop a model system of nematode defensive behaviors, with Caenorhabditis elegans as prey and Pristionchus pacificus as predator. In a foraging environment comprised of a food-rich, high-risk patch and a food-poor, low-risk refuge, C. elegans innately exhibits circa-strike behaviors. With experience, it learns post- and pre-encounter behaviors that proactively anticipate threats. These defense modes intensify with predator lethality, with only life-threatening predators capable of eliciting all three modes. SEB-3 receptors and NLP-49 peptides, key stress regulators, vary in their impact and interdependence across defense modes. Overall, our model system reveals fine-grained insights into how stress-related signaling regulates defensive behaviors.

ABSTRACTThe rapid development of technologies has attracted significant attention, with the social web and big data becoming key drivers of modern innovation. Although big data in the Social Internet of Things presents various energy‐saving merits, problems such as network congestion and data communication reliability occur. In this article, a hybrid channel attention recurrent transformer‐based adaptive marine predator algorithm is introduced to solve these problems. The main purpose of this approach is to improve the robustness and performance of SIoT systems. The hybrid channel attention recurrent transformer‐based adaptive marine predator algorithm combines a hybrid recurrent neural network, a channel attention mechanism, and a transformer classifier. In this work, four datasets, including the water treatment plant, GPS trajectories, hepatitis dataset, and Twitter for sentiment analysis in Arabic are employed in validating the performance of a proposed model. The Savitzky–Golay filter is applied to reduce noise and eliminate unnecessary or irrelevant data. After data pre‐processing, the hybrid channel attention recurrent transformer‐based adaptive marine predator was introduced for classification, and this model is fine‐tuned by the adaptive marine predator algorithm. In addition, the proposed model demonstrates strong scalability and applicability in real‐world applications, making it an ideal solution for future Social Internet of Things systems.

AbstractControl of introduced predators is essential for conserving many threatened species, but species range in vulnerability. Therefore, efficient conservation management requires estimating the vulnerabilities of different threatened species to introduced predators. Here, we quantify population responses of reintroduced toutouwai (Petroica longipes), popokatea (Mohoua albicilla) and tīeke (Philesturnus rufusater) to incursions of stoats (Mustela erminea) and cats (Felis catus) to a 588‐ha predator‐fenced sanctuary in Aotearoa New Zealand. There were fewer than 0.5 detections per year for both predator species from 2004 to 2016, but stoat detections increased >10‐fold from 2017 to 2019 and cats >30‐fold from 2020 to 2021. We estimated the growth and persistence of each bird population pre‐ and post‐2017. This involved fitting integrated population models to survival, reproduction and count data for toutouwai and tīeke, and fitting a variation of the Moran–Ricker model to 5‐min point counts for popokatea. We used these models to derive λmax, the finite rate of increase at zero density, which must be >1 for a population to persist. Popokatea showed no sign of impacts, with λmax estimated to be 1.68 (95% CRI 1.49–1.97) up to 2017 and 1.87 (1.42–2.62) after 2017. Toutouwai had tentative decreases in survival and reproduction, dropping the estimated λmax from 1.28 (1.10–1.51) to 1.06 (0.83–1.41). Tīeke survival dropped dramatically from 2017 to 2019, but returned to pre‐2017 levels when stoats were reduced, but recruitment was reduced and remained low, presumably due to cats. λmax was estimated to be 1.74 (1.04–2.70) on pre‐2017 rates; 1.14 (0.80–1.71) if only recruitment were predator‐affected; and 0.79 (0.36–1.36) if both adult survival and recruitment were predator‐affected. Our results therefore indicated that this level of stoat and cat incursion was inconsequential for popokatea, tentatively reduced toutouwai persistence from safe to marginal, and would have driven tīeke to extinction.

This research proposes an efficient deepfake detection system using a hybrid optimization model and a new deep learning approach. This system is divided into two phases: (i) the training Phase and (ii) the detection Phase. The decision phase is the ultimate decision maker, wherein a new deep learning approach referred to as ConvoReinAutoNet(CRAN) is introduced by levering the layers of Convolutional Neural Networks (CNN), Deep Reinforcement Learning (DRL), and Autoencoders, respectively. The training phase is enriched with new feature fusion and a hybrid optimization-based optimal feature selection approach. The extracted temporal and texture features (newly introduced Improved Local Ternary Patterns (I-LTP)) from the pre-processed images of the deepfake database are fused using the new GeoFisherNet. The newest hybrid optimization method called Marine Predator Customized White Shark Optimizer (MCWO) is used to select the best features among the combined features, which represents the combination of both the Marine Predator Algorithm (MPA) and White Shark Optimization Algorithm (WSO). The suggested model has been implemented in python and validated in terms of detection efficiency over the existing approaches.

AbstractIn order to effectively thwart predation, antipredator defensive behaviors must be matched to the current spatio-temporal relationship to the predator. We have proposed a model where different defensive responses are organized along a predatory imminence continuum (PIC). The PIC is a behavior system organized as a sequence of innately programmed behavioral modes, each representing a different interaction with the predator or threat. Ranging from low threat to predator contact, the PIC categorizes defense modes as pre-encounter, post-encounter, and circa-strike, corresponding to states of anxiety, fear, and panic, respectively. This experiment examined if the same significant stressor caused overexpression of all defensive responses along the PIC, including anxiety-like behavior, freezing, and panic-like responses. Female and male mice were exposed to acute stress that consisted of a series of ten pseudorandomly presented unsignaled footshocks (or no shocks). Mice were subsequently tested on a battery of tasks to assess stress effects on pre-encounter (anxiety-like), post-encounter (fear), and circa-strike (panic-like) behaviors. Results revealed that following stress, mice exhibited increased anxiety-like behavior shown through reduced average velocity within a modified open field. Furthermore, stressed mice showed increased fear following a single footshock in a new context as well as an increase in reactivity to white noise in the original stress context, with stressed mice exhibiting a more robust circa-strike-like response than controls. Therefore, significant stress exposure influenced the defensive states of anxiety, fear, and panic across the predatory imminence continuum. This research could therefore reveal how such responses become maladaptive following traumatic stress in humans.

Avoidance is a primary symptom of post‐traumatic stress disorder (PTSD). Our laboratory has established a rodent model of traumatic stress that mimics the avoidance symptom cluster of PTSD. Animals are classified as ‘Avoiders’ or Non‐Avoiders’ post‐stress based on avoidance of predator‐odor paired context. Previously we have demonstrated that Avoiders exhibit differences in neuronal activation patterns associated with re‐exposure to traumatic stress‐related stimuli. The central amygdala (CeA) is a brain region important for mediating emotional responses and fear. Humans with PTSD exhibit amygdalar hyperactivity in response to stimuli associated with their traumatic experiences. The aim of these studies was to examine the effects of traumatic stress on CeA neuronal activation as measured by increases in ERK phosphorylation and the role of ERK phosphorylation in mediating stress‐induced avoidance. Male Wistar rats (275g) were exposed to predator odor (bobcat urine) paired with context and were 1) sacrificed from home cage or re‐exposed to context prior to sacrifice for examination of ERK phosphorylation in the CeA or 2) infused with either vehicle or the ERK inhibitor (U0126; 1ug/0.5ul/side) and re‐tested for avoidance of the predator odor‐paired context. Re‐exposure to the predator‐odor paired context produced an increase in ERK phosphorylation in the CeA of Avoider rats relative to Non‐Avoider rats (2.69±0.76 vs. 1.44±0.46; p=NS). Furthermore, pre‐treatment with U0126 decreased avoidance compared to vehicle treated Avoider rats. These data provide insight into the neural mechanisms mediating stress‐induced avoidance.Support or Funding InformationThis work was supported by NIH grants: AA018400 (NWG), AA023305 (NWG).

ABSTRACTMarine protected areas (MPAs) have become the de‐facto mechanism for marine species conservation and management and the ecological benefits of no take zones (NTZs) are supported by an expanding scientific interest in their effectiveness. However, in the south‐western Baltic region there is a paucity of studies on the validity of MPAs, possibly due to the lack of enforcement. In this work we investigate the effects of nonconstant harvesting of a resource simultaneously under predation pressure. We use a functional response of the predator dependent Crowley‐Martin type in age‐structured state equations of a fixed time‐horizon optimal control problem, wherein a pre‐existing MPA may be encountered. Where available, only peer‐reviewed data and biomass stock levels are used for biological parameters in the state equations. Our results for the prey component of the model show that a moderate penalty exists that yields the same benefits as a fully closed reserve. However, taking into account the whole system we observe that an NTZ benefits the predator species too.

ABSTRACTDeimatic displays are visually conspicuous behaviours designed to prevent predation by scaring off predators. Animals that exhibit deimatic behaviours often show other secondary defences as well, but the factors that influence which defences are expressed are poorly understood. Because prey are expected to deploy multiple defences strategically, conspicuous deimatic displays could be performed later in the predation sequence after primary or other secondary defences have failed. Their expression could additionally depend on the state of the performer, especially if deimatic behaviours are costly to produce or involved in a functional trade‐off. Here, we investigate female defensive responses to escalating attacks involving non‐tactile and tactile stimuli by a human model predator using the springbok mantis, Miomantis caffra. We found that all defensive behaviours were expressed only after mantises were physically provoked, indicating a counter defence rather than a pre‐emptive one. Most females responded to initial tactile contact with non‐deimatic behaviours—most commonly fleeing, but also striking with raptorial forelegs and freezing. When predator attacks escalated and tactile contact increased, females mostly produced deimatic behaviours, including raising forelegs, flaring wings, exposing jaws and/or swaying from side to side. Females that were heavier for their size and therefore closer to oviposition were also less likely to flee and more likely to strike and display, although this pattern depended on the level of predator threat. Our results suggest that the expression of deimatic displays is prompted by the repeated failure of non‐deimatic defences to ward off escalating predator attacks, which may be why deimatism has gone unnoticed in M. caffra until now. Our findings also suggest an important role for fight‐or‐flight trade‐offs in the expression of antipredator behaviours in this species: heavier egg‐loads appear to compromise females' ability to flee, triggering more aggressive and deimatic responses instead.

Trauma, as well as chronic stress that characterizes a modern fast-paced lifestyle, contributes to numerous psychopathologies and psychological problems. Psychiatric patients with traumas, as well as healthy individuals who experienced traumas in the past, are often characterized by diminished cognitive abilities. In our protocol, we used an animal model to explore the influence of chronic trauma on cognitive abilities and behavior in the group of 20 rats (Rattus norvegicus). The experimental group was introduced to chronic (12 consecutive days) exposure to predator odor (bobcat urine). We measured the reinforcement learning of each individual before and after the exposition via the Probabilistic Selection Task (PST) and we used Social Interaction Test (SIT) to assess the behavioral changes of each individual before and after the trauma. In the experimental group, there was a significant decrease in reinforcement learning after exposure to a single trauma (Wilcoxon Test, p = 0.034) as well as after 11 days of chronic trauma (Wilcoxon-test, p = 0.01) in comparison to pre-trauma performance. The control group, which was not exposed to predator odor but underwent the same testing protocol, did not present significant deterioration in reinforcement learning. In cross-group comparisons, there was no difference between the experimental and control group in PST before odor protocol (U Mann-Whitney two-sided, p = 0.909). After exposure to chronic trauma, the experimental group deteriorated in PST performance compared to control (U Mann-Whitney Two-sided, p = 0.0005). In SIT, the experimental group spent less time in an Interaction Zone with an unfamiliar rat after trauma protocol (Wilcoxon two-sided test, p = 0.019). Major strengths of our models are: (1) protocol allows investigating reinforcement learning before and after exposition to chronic trauma, with the same group of rats, (2) translational scope, as the PST is displayed on touchscreen, similarly to human studies, (3) protocol delivers chronic trauma that impairs reward learning, but behaviorally does not induce full-blown anhedonia, thus rats performed voluntarily throughout all the procedures.

Abstract Mating cues are often comprised of several elements, which can act independently, or in concert to attract a suitable partner. Individual elements may also function in other contexts, such as anti-predator defense or camouflage. In Heliconius butterflies, wing patterns comprise several individual color pattern elements, which advertise the butterflies’ toxicity to predators. These wing patterns are also mating cues, and males predominantly court females that possess the same wing pattern as their own. However, it is not known whether male preference is based on the full wing pattern or only individual pattern elements. We compared preferences of male H. erato lativitta between female models with the full wing pattern and those with some pattern elements removed. We found no differences in preference between the full wing pattern model and a model with pattern elements removed, indicating that the complete composition of all elements is not essential to the mating signal. Wing pattern preferences also contribute to pre-mating isolation between two other Heliconius taxa, H. erato cyrbia and H. himera, therefore, we next compared preferences for the same models in these species. H. erato cyrbia and H. himera strongly differed in preferences for the models, potentially providing a mechanism for how pre-mating isolation acts between these species. These findings suggest that contrasting levels of selective constraint act on elements across the wing pattern

Abstract Mimicry is an excellent example of how natural selection can act on color, morphology, and behavior of species. Herein we assess predation rates on coral snake mimics in Central Brazil, a region with many mimics but only a single model, to answer the following questions: (i) Do predators avoid attacking coral snake mimics? (ii) Does the degree to which mimics resemble their venomous model affect the frequency of predator attacks? (iii) Do predators attack different body regions in mimics with different color patterns? Our experiment was conducted in the Chapada dos Veadeiros National Park, in the municipality of Alto Paraíso de Goiás, state of Goiás, Brazil. To evaluate predation rates on the different mimic patterns, we made 2,400 clay snake replicas using pre-colored nontoxic plasticine and distributed them in open savanna landscapes within the park. A total of 164 (6.83%) replicas were attacked by predators of snakes. Among these attacks, 121 were attacks by birds, and 43 were attacks by carnivorous mammals. Logistic regression and Fisher’s exact test indicated that replicas with red, white, and black coloration are less likely to be attacked than were grey replicas, and coral snake replicas were attacked more often at the “head” end. Also, the greater the similarity to the pattern of venomous coral snakes, the rarer the attack on the replica. Our study underscores the strong selective force that protects coral snake mimics from predators. Our findings reinforce resemblance to the model as an extremely effective strategy in a complex natural system with only one model and numerous mimics.

Abstract Noise pollution poses a significant threat to ecosystems worldwide, disrupting animal communication and causing cascading effects on biodiversity. In this study, we focus on the impact of snowmobile noise on avian vocalizations during the non‐breeding winter season, a less‐studied area in soundscape ecology. We developed a pipeline relying on deep learning methods to detect snowmobile noise and applied it to a large acoustic monitoring dataset collected in Yellowstone National Park. Our results demonstrate the effectiveness of the snowmobile detection model in identifying snowmobile noise and reveal an association between snowmobile passage and changes in avian vocalization patterns. Snowmobile noise led to a decrease in the frequency of bird vocalizations during mornings and evenings, potentially affecting winter and pre‐breeding behaviours such as foraging, predator avoidance and successfully finding a mate. However, we observed a recovery in avian vocalizations after detection of snowmobiles during mornings and afternoons, indicating some resilience to sporadic noise events. Synthesis and applications: Our findings emphasize the need to consider noise impacts in the non‐breeding season and provide valuable insights for natural resource managers to minimize disturbance and protect critical avian habitats. The deep learning approach presented in this study offers an efficient and accurate means of analysing large‐scale acoustic monitoring data and contributes to a comprehensive understanding of the cumulative impacts of multiple stressors on avian communities.

Memory impairment in Alzheimer’s disease patients is thought to be associated with the accumulation of amyloid-beta peptides and tau proteins. However, inconsistent reports of cognitive deficits in pre-clinical studies have raised questions about the link between amyloid-beta and cognitive decline. One possible explanation may be that studies reporting memory deficits often involve behavioral assessments that entail a high stress component. In contrast, in tasks without a high stress component transgenic mice do not consistently show declines in memory. The glucocorticoid cascade hypothesis of aging and the vicious cycle of stress framework suggest that stress exacerbates dementia progression by initiating a cycle of hypothalamic-pituitary-adrenal axis activation and subsequent brain deterioration. Using the APPswe/PS1dE9 mouse model of amyloidosis, we assessed whether stressor exposure prior to testing differentially impaired cognitive performance of aged male and female mice. As part of a larger study, mice performed a delayed match-to-position (DMTP) or a 3-choice serial-reaction time (3CSRT) task. Unexpectedly, these mice did not exhibit cognitive declines during aging. Therefore, at 73 and 74 weeks of age, we exposed mice to a predator odor or forced swim stressor prior to testing to determine if stress revealed cognitive deficits. We predicted stressor exposure would decrease performance accuracy more robustly in transgenic vs. non-transgenic mice. Acute stressor exposure increased accuracy in the DMTP task, but not in the 3CSRT task. Our data suggest that acute stressor exposure prior to testing does not impair cognitive performance in APPswe/PS1dE9 mice.

AbstractAnimal vigilance is often investigated under a narrow set of scenarios, but this approach may overestimate its contribution to animal lives. A solution may be to sample all looking behaviours and investigate numerous competing hypotheses in a single analysis. In this study, using a wild group of habituated chacma baboons (Papio ursinus griseipes) as a model system, we implemented a framework for predicting the key drivers of looking by comparing the strength of a full array of biological hypotheses. This included methods for defining individual-specific social threat environments, quantifying individual tolerance to human observers, and incorporating predator resource selection functions. Although we found evidence supporting reactionary and within-group (social) vigilance hypotheses, risk factors did not predict looking with the greatest precision, suggesting vigilance was not a major component of the animals’ behavioural patterns generally. Instead, whilst some behaviours constrain opportunities for looking, many shared compatibility with looking, alleviating the pressure to be pre-emptively vigilant for threats. Exploring looking patterns in a thorough multi-hypothesis framework should be feasible across a range of taxa, offering new insights into animal behaviour that could alter our concepts of fear ecology.

In recent years, the utilization of biocontrol agents to administer agriculture pests has received more attention, which has conduce to an growth in companies generating biocontrol agents, including predators and parasitoids. Amblyseius swirskii Athias-Henriot as a part of predatory communities in greenhouses is currently used worldwide as a biocontrol agent against small insects and various mites, especially to suppress the population of the two-spotted spider mite (TSSM), Tetranychus urticae Koch. To improve mass rearing of A. swirskii and optimize its application in integrated pest management programs, its development rate was determined at seven constant temperatures ranging from 15 to 34 (±1)°C, 50±10% RH and a photoperiod of 16:8 (L:D) h under laboratory conditions. None of the eggs hatched at 34°C and no development was observed. To determine the lower temperature threshold (T0) and thermal constant (K) of different stages of the predator, two linear models (ordinary and Ikemoto) were used. In addition, 26 nonlinear models were fitted to evaluate the development rate at different temperatures. The lower temperature threshold (T0) and thermal constant (K) of total immature stages were estimated by the ordinary (3.72°C and 133.22 DD) and Ikemoto (10.64°C and 86.51DD) linear models. Based on the Akaike information criterion (AIC), the best model for the description of the temperature-dependent development rate of the egg, larval, protonymphal, and dutonymphal stages was the Ratkowsky model and for the whole pre-adult stage, it was the Logan-6 model. Our results provided a detailed evaluation of the thermal requirements of A. swirskii, which can be important in improving the role of this mite in biological control programs.

Although many countries have formally committed to Ecosystem-Based Fisheries Management (EBFM), actual progress toward these goals has been slow. This paper presents two independent case studies that have combined strategic advice from ecosystem modeling with the tactical advice of single-species assessment models to provide practical ecosystem-based management advice. With this approach, stock status, reference points, and initial target F are computed from a single-species model, then an ecosystem model rescales the target F according to ecosystem indicators without crossing pre-calculated single-species precautionary limits. Finally, the single-species model computes the quota advice from the rescaled target F, termed here Feco. Such a methodology incorporates both the detailed population reconstructions of the single-species model and the broader ecosystem perspective from ecosystem-based modeling, and fits into existing management schemes. The advocated method has arisen from independent work on EBFM in two international fisheries management systems: (1) Atlantic menhaden in the United States and (2) the multi species fisheries of the Irish Sea, in the Celtic Seas ecoregion. In the Atlantic menhaden example, the objective was to develop ecological reference points (ERPs) that account for the effect of menhaden harvest on predator populations and the tradeoffs associated with forage fish management. In the Irish Sea, the objective was to account for ecosystem variability when setting quotas for the individual target species. These two exercises were aimed at different management needs, but both arrived at a process of adjusting the target F used within the current single-species management. Although the approach has limitations, it represents a practical step toward EBFM, which can be adapted to a range of ecosystem objectives and applied within current management systems.

Although many countries have formally committed to Ecosystem-Based Fisheries Management (EBFM), actual progress toward these goals has been slow. This paper presents two independent case studies that have combined strategic advice from ecosystem modeling with the tactical advice of single-species assessment models to provide practical ecosystem-based management advice. With this approach, stock status, reference points, and initial target F are computed from a single-species model, then an ecosystem model rescales the target F according to ecosystem indicators without crossing pre-calculated single-species precautionary limits. Finally, the single-species model computes the quota advice from the rescaled target F, termed here Feco. Such a methodology incorporates both the detailed population reconstructions of the single-species model and the broader ecosystem perspective from ecosystem-based modeling, and fits into existing management schemes. The advocated method has arisen from independent work on EBFM in two international fisheries management systems: (1) Atlantic menhaden in the United States and (2) the multi species fisheries of the Irish Sea, in the Celtic Seas ecoregion. In the Atlantic menhaden example, the objective was to develop ecological reference points (ERPs) that account for the effect of menhaden harvest on predator populations and the tradeoffs associated with forage fish management. In the Irish Sea, the objective was to account for ecosystem variability when setting quotas for the individual target species. These two exercises were aimed at different management needs, but both arrived at a process of adjusting the target F used within the current single-species management. Although the approach has limitations, it represents a practical step toward EBFM, which can be adapted to a range of ecosystem objectives and applied within current management systems.

IntroductionDepending on the individual, exposure to an intense stressor may, or may not, lead to a stress-induced pathology. Predicting the physiopathological evolution in an individual is therefore an important challenge, at least for prevention. In this context, we developed an ethological model of simulated predator exposure in rats: we call this the multisensorial stress model (MSS). We hypothesized that: (i) MSS exposure can induce stress-induced phenotypes, and (ii) an electrocorticogram (ECoG) recorded before stress exposure can predict phenotypes observed after stress.MethodsForty-five Sprague Dawley rats were equipped with ECoG telemetry and divided into two groups. The Stress group (n = 23) was exposed to an MSS that combined synthetic fox feces odor deposited on filter paper, synthetic blood odor, and 22 kHz rodent distress calls; the Sham group (n = 22) was not exposed to any sensorial stimulus. Fifteen days after initial exposure, the two groups were re-exposed to a context that included a filter paper soaked with water as a traumatic object (TO) reminder. During this re-exposure, freezing behavior and avoidance of the filter paper were measured.ResultsThree behaviors were observed in the Stress group: 39% developed a fear memory phenotype (freezing, avoidance, and hyperreactivity); 26% developed avoidance and anhedonia; and 35% made a full recovery. We also identified pre-stress ECoG biomarkers that accurately predicted cluster membership. Decreased chronic 24 h frontal Low θ relative power was associated with resilience; increased frontal Low θ relative power was associated with fear memory; and decreased parietal β2 frequency was associated with the avoidant-anhedonic phenotype.DiscussionThese predictive biomarkers open the way to preventive medicine for stress-induced diseases.

Stream restoration programs employ beaver‐related restoration techniques, including beaver translocations and installation of beaver dam analogs (BDA), to create complex in‐stream habitat. We investigated whether BDA installations improved the probability of translocated beavers surviving and colonizing a section of a degraded desert river. We translocated beavers fitted with tracking devices to the Price River, Utah, United States, for 2 years before and after BDAs were installed. We monitored survival and site fidelity of beavers to estimate apparent survival (φ), using model selection to evaluate models with BDA, flow, and other factors hypothesized to relate to apparent survival. We found similar apparent survival 8 weeks post‐release of pre‐BDA (φ = 0.50 ± 0.08 SE) and post‐BDA beavers (φ = 0.41 ± 0.06 SE). There were 15 predator‐caused mortalities and 39 beavers emigrated out of the study site. Top models indicated apparent survival was negatively related to mean flow. Of the 70 BDAs constructed, beaver activity was detected on only two structures and the number of intact natural dams decreased due to monsoon floods. Our results suggest BDAs may not improve survival and site fidelity of translocated beavers in desert river systems. Instead, the dynamic flow of desert rivers and negative relationship between flow and apparent survival suggest the timing of release may be an important consideration for successful beaver translocation. Additional research is needed to understand how habitat, food availability, individual behavior, and resident conspecifics influence beaver translocation success.