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1
Bussell, Sue, and John Farrow. "Practitioner Review: Continuity and Change: The Fair Work Act in Aviation." Journal of Industrial Relations 53, no. 3 (June 2011): 392–401. http://dx.doi.org/10.1177/0022185611401997.
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This article begins by discussing the specific industrial relations challenges of the highly competitive aviation industry. It then reflects on the outcome of the recent intense national debate over industrial relations, exploring the consequences of that debate for practice and policy, and discusses some key issues that remain in play. Although the Fair Work Act 2009 may have come about as a reaction to what many perceive as the ‘excesses’ of Work Choices, the new Act does not so much ‘wind back the clock’ as represent a significant new development in Australia’s long and unique industrial relations history. This article will discuss the impact of the changes, to date, made by the Fair Work Act on one organization, including the expansion of the ‘safety net’, and how the new compromise between the role of the ‘collective’ and the role of the ‘individual’ struck by the Act has the potential to fundamentally change the nature and structure of bargaining. We offer these comments as practitioners who have worked under successive industrial relations regimes since the early 1980s.
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Chou, Hsi-Chiang. "Concrete Object Anomaly Detection Using a Nondestructive Automatic Oscillating Impact-Echo Device." Applied Sciences 9, no. 5 (March 4, 2019): 904. http://dx.doi.org/10.3390/app9050904.
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The goal of this study was to develop an impact-echo device that can conduct automatic oscillation tests, process signals rapidly, and apply it to concrete object anomaly analysis. The system presented in this study comprises three parts, namely the impact device, the oscillator circuit, and signal processing software. The design concept of the impact-echo device was inspired by a pendulum clock, and its implementation used a nondestructive wooden hammer instead of a conventional manual steel hammer. In this study, we used a pulse generator in the adjustable oscillator circuit to produce delayed changes. The delayed changes would activate the wooden hammer that struck the surface of the object. To process the signal, our lab used a built-in sound card in the computer to transfer the reflection soundwave from striking the wall to MATLAB software to analyze the energy of the frequency spectrum. This was conducted to evaluate whether the object contained anomalies and, if so, to determine the location of the anomalies to serve as a reference for real-life implementation.
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Kippert, Fred. "Cellular signalling and the complexity of biological timing: insights from the ultradian clock of Schizosaccharomyces pombe." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 356, no. 1415 (November 29, 2001): 1725–33. http://dx.doi.org/10.1098/rstb.2001.0935.
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The molecular bases of circadian clocks are complex and cannot be sufficiently explained by the relatively simple feedback loops, based on transcription and translation, of current models. The existence of additional oscillators has been demonstrated experimentally, but their mechanism(s) have so far resisted elucidation and any universally conserved clock components have yet to be identified. The fission yeast, Schizosaccharomyces pombe , as a simple and well–characterized eukaryote, is a useful model organism in the investigation of many aspects of cell regulation. In fast–growing cells of the yeast an ultradian clock operates, which can serve as a model system to analyse clock complexity. This clock shares strict period homeostasis and efficient entrainment with circadian clocks but, because of its short period of 30 min, mechanisms other than a transcription/translation–based feedback loop must be working. An initial systematic screen involving over 200 deletion mutants has shown that major cellular signalling pathways (calcium/phosphoinositide, mitogen–activated protein kinase and cAMP/protein kinase A) are crucial for the normal functioning of this ultradian clock. A comparative examination of the role of cellular signalling pathways in the S.pombe ultradian clock and in the circadian timekeeping of different eukaryotes may indicate common principles in biological timing processes that are universally conserved amongst eukaryotes.
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Wu, Guowei, Xiaojie Chen, Lin Yao, Youngjun Lee, and Kangbin Yim. "An efficient wormhole attack detection method in wireless sensor networks." Computer Science and Information Systems 11, no. 3 (2014): 1127–41. http://dx.doi.org/10.2298/csis130921068w.
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Wireless sensor networks are now widely used in many areas, such as military, environmental, health and commercial applications. In these environments, security issues are extremely important since a successful attack can cause great damage, even threatening human life. However, due to the open nature of wireless communication, WSNs are liable to be threatened by various attacks, especially destructive wormhole attack, in which the network topology is completely destroyed. Existing some solutions to detect wormhole attacks require special hardware or strict synchronized clocks or long processing time. Moreover, some solutions cannot even locate the wormhole. In this paper, a wormhole attack detection method is proposed based on the transmission range that exploits the local neighborhood information check without using extra hardware or clock synchronizations. Extensive simulations are conducted under different mobility models. Simulation results indicate that the proposed method can detect wormhole attacks effectively and efficiently in WSNs.
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Wang, Xiao, and Zhi Bin Zeng. "A Design for Clock Synchronization Using CPPLL." Applied Mechanics and Materials 543-547 (March 2014): 558–61. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.558.
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High performance clock synchronization system is essential in communication transmission, which is based on the principle of phase locked loop synchronization that tracking a high accuracy, high stability reference clock source usinh low-pass filter to turn the value into voltage and to control VCO or VXCO and makes the output frequency and the input frequency to maintain strict synchronization.
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Wang, Xiao, and Zhi Bin Zeng. "A Design of CPPLL for CMMB Broadcasting System." Applied Mechanics and Materials 556-562 (May 2014): 1597–600. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.1597.
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As an important module in CMMB system, the performance of phase locked loop will directly determines the accuracy, purity and synchronization of system clock. In this paper, a high performance CPPLL circuit is designed to make each system clock of base station to get strict synchronization in frequency and phase. Test results show that the performance of this design meets the CMMB system requirements
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Didelot, Xavier, Igor Siveroni, and Erik M. Volz. "Additive Uncorrelated Relaxed Clock Models for the Dating of Genomic Epidemiology Phylogenies." Molecular Biology and Evolution 38, no. 1 (July 28, 2020): 307–17. http://dx.doi.org/10.1093/molbev/msaa193.
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Abstract Phylogenetic dating is one of the most powerful and commonly used methods of drawing epidemiological interpretations from pathogen genomic data. Building such trees requires considering a molecular clock model which represents the rate at which substitutions accumulate on genomes. When the molecular clock rate is constant throughout the tree then the clock is said to be strict, but this is often not an acceptable assumption. Alternatively, relaxed clock models consider variations in the clock rate, often based on a distribution of rates for each branch. However, we show here that the distributions of rates across branches in commonly used relaxed clock models are incompatible with the biological expectation that the sum of the numbers of substitutions on two neighboring branches should be distributed as the substitution number on a single branch of equivalent length. We call this expectation the additivity property. We further show how assumptions of commonly used relaxed clock models can lead to estimates of evolutionary rates and dates with low precision and biased confidence intervals. We therefore propose a new additive relaxed clock model where the additivity property is satisfied. We illustrate the use of our new additive relaxed clock model on a range of simulated and real data sets, and we show that using this new model leads to more accurate estimates of mean evolutionary rates and ancestral dates.
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VELENIS, D., K. T. TANG, I. S. KOURTEV, V. ADLER, F. BAEZ, and E. G. FRIEDMAN. "DEMONSTRATION OF SPEED AND POWER ENHANCEMENTS ON AN INDUSTRIAL CIRCUIT THROUGH APPLICATION OF CLOCK SKEW SCHEDULING." Journal of Circuits, Systems and Computers 11, no. 03 (June 2002): 231–45. http://dx.doi.org/10.1142/s0218126602000410.
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A strategy to enhance the speed and power characteristics of an industrial circuit is demonstrated in this paper. It is shown that nonzero clock skew scheduling can improve circuit performance while relaxing the strict timing constraints of the critical data paths within a high speed system. A software tool implementing a nonzero clock skew scheduling algorithm is described together with a methodology that generates the required clock signal delays. Furthermore, a technique that significantly reduces the power dissipated in the noncritical data paths is demonstrated. The application of this technique combined with nonzero clock skew scheduling to the slower data paths is also described. Speed improvements of up to 18% and power savings greater than 80% are achieved in certain functional blocks of an industrial high performance microprocessor.
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Lemieszewski, Łukasz, Aleksandra Radomska-Zalas, Andrzej Perec, Larisa Dobryakova, and Evgeny Ochin. "The Spoofing Detection of Dynamic Underwater Positioning Systems (DUPS) Based on Vehicles Retrofitted with Acoustic Speakers." Electronics 10, no. 17 (August 28, 2021): 2089. http://dx.doi.org/10.3390/electronics10172089.
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The need of precision for underwater positioning and navigation should be considered as strict as those present at the sea surface. GNSS provides 4D positioning (XYZT). Each satellite contains two rubidium and two cesium atomic clocks. They are monitored by an atomic clock on the ground, and the entire system is constantly calibrated to a universal time standard, Coordinated Universal Time (UTC). GNSS receivers determine the time T to within 100 billionths of a second without the cost of owning, operating and maintaining an atomic clock. Of particular importance is the measurement of XYZT underwater. We assume that some surface vehicles are additionally equipped with an Acoustic Speaker, which transmits the XY coordinates of the vessel with an indication of accuracy and the time T of the vessel. Submarine vehicles determine their position by help of acoustic signals from several surface acoustic sources using the Time of Arrival (ToA) algorithm. Detection of Spoofing for the Dynamic Underwater Positioning Systems (DUPS) based on vehicles retrofitted with acoustic speakers is very actual problem. Underwater spoofing works as follows: N acoustic speaker on N ships transmit the coordinates {xi,yi,ti}, i=1,N¯. GNSS signals are susceptible to interference due to their very low power (−130 dBm) and can be easily jammed by other sources, which may be accidental or intentional. The spoofer, like an underwater vehicle, receives these signals from N vessels, distorts them and transmits with increased acoustic power. All receivers into the spoofed area will calculate the same coordinates, so the indication of the coincidence of coordinates from a pair of diversity receivers is an indication of spoofing detection.
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Renner, Susanne S. "Multiple Miocene Melastomataceae dispersal between Madagascar, Africa and India." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 359, no. 1450 (October 29, 2004): 1485–94. http://dx.doi.org/10.1098/rstb.2004.1530.
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Melastomataceae sensu stricto (excluding Memecylaceae) comprise some 3000 species in the neotropics, 1000 in Asia, 240 in Africa, and 230 in Madagascar. Previous family–wide morphological and DNA analyses have shown that the Madagascan species belong to at least three unrelated lineages, which were hypothesized to have arrived by trans–oceanic dispersal. An alternative hypothesis posits that the ancestors of Madagascan, as well as Indian, Melastomataceae arrived from Africa in the Late Cretaceous. This study tests these hypotheses in a Bayesian framework, using three combined sequence datasets analysed under a relaxed clock and simultaneously calibrated with fossils, some not previously used. The new fossil calibration comes from a re–dated possibly Middle or Upper Eocene Brazilian fossil of Melastomeae. Tectonic events were also tentatively used as constraints because of concerns that some of the family's fossils are difficult to assign to nodes in the phylogeny. Regardless of how the data were calibrated, the estimated divergence times of Madagascan and Indian lineages were too young for Cretaceous explanations to hold. This was true even of the oldest ages within the 95% credibility interval around each estimate. Madagascar's Melastomeae appear to have arrived from Africa during the Miocene. Medinilla , with some 70 species in Madagascar and two in Africa, too, arrived during the Miocene, but from Asia. Gravesia , with 100 species in Madagascar and four in east and west Africa, also appears to date to the Miocene, but its monophyly has not been tested. The study afforded an opportunity to compare divergence time estimates obtained earlier with strict clocks and single calibrations, with estimates based on relaxed clocks and different multiple calibrations and taxon sampling.
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Beavan, Alan J. S., Philip C. J. Donoghue, Mark A. Beaumont, and Davide Pisani. "Performance of A Priori and A Posteriori Calibration Strategies in Divergence Time Estimation." Genome Biology and Evolution 12, no. 7 (May 22, 2020): 1087–98. http://dx.doi.org/10.1093/gbe/evaa105.
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Abstract Relaxed molecular clock methods allow the use of genomic data to estimate divergence times across the tree of life. This is most commonly achieved in Bayesian analyses where the molecular clock is calibrated a priori through the integration of fossil information. Alternatively, fossil calibrations can be used a posteriori, to transform previously estimated relative divergence times that were inferred without considering fossil information, into absolute divergence times. However, as branch length is the product of the rate of evolution and the duration in time of the considered branch, the extent to which a posteriori calibrated, relative divergence time methods can disambiguate time and rate, is unclear. Here, we use forward evolutionary simulations and compare a priori and a posteriori calibration strategies using different molecular clock methods and models. Specifically, we compare three Bayesian methods, the strict clock, uncorrelated clock and autocorrelated clock, and the non-Bayesian algorithm implemented in RelTime. We simulate phylogenies with multiple, independent substitution rate changes and show that correct timescales cannot be inferred without the use of calibrations. Under our simulation conditions, a posteriori calibration strategies almost invariably inferred incorrect rate changes and divergence times. The a priori integration of fossil calibrations is fundamental in these cases to improve the accuracy of the estimated divergence times. Relative divergence times and absolute timescales derived by calibrating relative timescales to geological time a posteriori appear to be less reliable than a priori calibrated, timescales.
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Holder, Nakisha D., Catherine Wilson, Cindy Elder, Terry P. Yamaguchi, Gregg Duester, and Mark Lewandoski. "Fgf4 and Fgf8 are required for maintenance of the primitive streak and somitic clock." Developmental Biology 306, no. 1 (June 2007): 401. http://dx.doi.org/10.1016/j.ydbio.2007.03.602.
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Tao, Qiqing, Koichiro Tamura, Beatriz Mello, and Sudhir Kumar. "Reliable Confidence Intervals for RelTime Estimates of Evolutionary Divergence Times." Molecular Biology and Evolution 37, no. 1 (October 22, 2019): 280–90. http://dx.doi.org/10.1093/molbev/msz236.
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Abstract Confidence intervals (CIs) depict the statistical uncertainty surrounding evolutionary divergence time estimates. They capture variance contributed by the finite number of sequences and sites used in the alignment, deviations of evolutionary rates from a strict molecular clock in a phylogeny, and uncertainty associated with clock calibrations. Reliable tests of biological hypotheses demand reliable CIs. However, current non-Bayesian methods may produce unreliable CIs because they do not incorporate rate variation among lineages and interactions among clock calibrations properly. Here, we present a new analytical method to calculate CIs of divergence times estimated using the RelTime method, along with an approach to utilize multiple calibration uncertainty densities in dating analyses. Empirical data analyses showed that the new methods produce CIs that overlap with Bayesian highest posterior density intervals. In the analysis of computer-simulated data, we found that RelTime CIs show excellent average coverage probabilities, that is, the actual time is contained within the CIs with a 94% probability. These developments will encourage broader use of computationally efficient RelTime approaches in molecular dating analyses and biological hypothesis testing.
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Coiffard, Benjamin, Aïssatou Bailo Diallo, Soraya Mezouar, Marc Leone, and Jean-Louis Mege. "A Tangled Threesome: Circadian Rhythm, Body Temperature Variations, and the Immune System." Biology 10, no. 1 (January 18, 2021): 65. http://dx.doi.org/10.3390/biology10010065.
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The circadian rhythm of the body temperature (CRBT) is a marker of the central biological clock that results from multiple complex biological processes. In mammals, including humans, the body temperature displays a strict circadian rhythm and has to be maintained within a narrow range to allow optimal physiological functions. There is nowadays growing evidence on the role of the temperature circadian rhythm on the expression of the molecular clock. The CRBT likely participates in the phase coordination of circadian timekeepers in peripheral tissues, thus guaranteeing the proper functioning of the immune system. The disruption of the CRBT, such as fever, has been repeatedly described in diseases and likely reflects a physiological process to activate the molecular clock and trigger the immune response. On the other hand, temperature circadian disruption has also been described as associated with disease severity and thus may mirror or contribute to immune dysfunction. The present review aims to characterize the potential implication of the temperature circadian rhythm on the immune response, from molecular pathways to diseases. The origin of CRBT and physiological changes in body temperature will be mentioned. We further review the immune biological effects of temperature rhythmicity in hosts, vectors, and pathogens. Finally, we discuss the relationship between circadian disruption of the body temperature and diseases and highlight the emerging evidence that CRBT monitoring would be an easy tool to predict outcomes and guide future studies in chronotherapy.
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Jouve, Caroline, Tadahiro Iimura, and Olivier Pourquie. "Onset of the segmentation clock in the chick embryo: evidence for oscillations in the somite precursors in the primitive streak." Development 129, no. 5 (March 1, 2002): 1107–17. http://dx.doi.org/10.1242/dev.129.5.1107.
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Vertebrate somitogenesis is associated with a molecular oscillator, the segmentation clock, which is defined by the periodic expression of genes related to the Notch pathway such as hairy1 and hairy2 or lunatic fringe (referred to as the cyclic genes) in the presomitic mesoderm (PSM). Whereas earlier studies describing the periodic expression of these genes have essentially focussed on later stages of somitogenesis, we have analysed the onset of the dynamic expression of these genes during chick gastrulation until formation of the first somite. We observed that the onset of the dynamic expression of the cyclic genes in chick correlated with ingression of the paraxial mesoderm territory from the epiblast into the primitive streak. Production of the paraxial mesoderm from the primitive streak is a continuous process starting with head mesoderm formation, while the streak is still extending rostrally, followed by somitic mesoderm production when the streak begins its regression. We show that head mesoderm formation is associated with only two pulses of cyclic gene expression. Because such pulses are associated with segment production at the body level, it suggests the existence of, at most, two segments in the head mesoderm. This is in marked contrast to classical models of head segmentation that propose the existence of more than five segments. Furthermore, oscillations of the cyclic genes are seen in the rostral primitive streak, which contains stem cells from which the entire paraxial mesoderm originates. This indicates that the number of oscillations experienced by somitic cells is correlated with their position along the AP axis.
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Matzke, Nicholas J., and Randall B. Irmis. "Including autapomorphies is important for paleontological tip-dating with clocklike data, but not with non-clock data." PeerJ 6 (April 6, 2018): e4553. http://dx.doi.org/10.7717/peerj.4553.
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Tip-dating, where fossils are included as dated terminal taxa in Bayesian dating inference, is an increasingly popular method. Data for these studies often come from morphological character matrices originally developed for non-dated, and usually parsimony, analyses. In parsimony, only shared derived characters (synapomorphies) provide grouping information, so many character matrices have an ascertainment bias: they omit autapomorphies (unique derived character states), which are considered uninformative. There has been no study of the effect of this ascertainment bias in tip-dating, but autapomorphies can be informative in model-based inference. We expected that excluding autapomorphies would shorten the morphological branchlengths of terminal branches, and thus bias downwards the time branchlengths inferred in tip-dating. We tested for this effect using a matrix for Carboniferous-Permian eureptiles where all autapomorphies had been deliberately coded. Surprisingly, date estimates are virtually unchanged when autapomorphies are excluded, although we find large changes in morphological rate estimates and small effects on topological and dating confidence. We hypothesized that the puzzling lack of effect on dating was caused by the non-clock nature of the eureptile data. We confirm this explanation by simulating strict clock and non-clock datasets, showing that autapomorphy exclusion biases dating only for the clocklike case. A theoretical solution to ascertainment bias is computing the ascertainment bias correction (Mkparsinf), but we explore this correction in detail, and show that it is computationally impractical for typical datasets with many character states and taxa. Therefore we recommend that palaeontologists collect autapomorphies whenever possible when assembling character matrices.
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Putterill, Jo. "Flowering in time: genes controlling photoperiodic flowering in Arabidopsis." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 356, no. 1415 (November 29, 2001): 1761–67. http://dx.doi.org/10.1098/rstb.2001.0963.
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Successful sexual reproduction in plants relies upon the strict coordination of flowering time with favourable seasons of the year. One of the most important seasonal cues for the model plant Arabidopsis thaliana ( Arabidopsis ) is day length. Genes influencing flowering time in Arabidopsis have been isolated, some of which are involved in the perception and signalling of day length. This review discusses recent progress that has been made in understanding how Arabidopsis integrates environmental and internal signals to ensure a sharp transition to flowering and new insights on the role of the circadian clock in controlling the expression of genes that promote flowering in response to day length.
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Roy, Nirupam. "Owlet." GetMobile: Mobile Computing and Communications 25, no. 2 (September 14, 2021): 14–20. http://dx.doi.org/10.1145/3486880.3486884.
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Miniaturization is an inherent trend in ubiquitous computing. Insect-scale robots add new capabilities to disaster management, tiny headphones are emerging as complete computing devices, and small wearable health monitors can track vital signs around the clock. Advancements in sensing technologies play a pivotal role in this development. Spatial sensing at this form factor, however, is a skill yet to be mastered, particularly at low-frequency signals like audible sounds. Traditionally, spatial sensing requires sampling in both time and space using an array of microphones, which comes with a strict size requirement and multiplies its power requirement. In this article, we explore the possibility of an alternative design for spatial sensing for miniaturized and power-constrained devices.
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Li, Jiquan, Yingmei Chen, Pan Tang, Zhen Zhang, Hui Wang, and Hao Huang. "A Low-Power Low-Distortion 20-GS/s Flash Analog-to-Digital Converter for Coherent Optical Receiver in 0.13-μm SiGe BiCMOS." Journal of Circuits, Systems and Computers 28, no. 10 (September 2019): 1950167. http://dx.doi.org/10.1142/s0218126619501676.
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High-speed, low-power analog-to-digital converter (ADC) is a critical element for 5-GBd, 20-Gb/s digital signal processing (DSP)-based coherent optical communication receiver. To satisfy high data transmission rate requirement of optical receiver, a single-core and open-loop flash ADC with a new proposed multiplexer-based encoder is presented in this paper. Compared with conventional encoder topology, the new proposed topology achieves the fastest encoding speed and lowest power consumption. The optimized distortion is achieved by utilizing a leakage current compensation technique and a local negative feedback method in switched-buffer track-and-hold amplifier (THA). Strict synchronization is obtained for clock signals by careful designing of layout in tree-based clock networks. Furthermore, a master–slave comparator incorporated with a preamplifier reduces signal-dependent kickback noise as well as offset voltage. By using master–slave comparators and proposed encoders, the sampling rate is up to 21.12[Formula: see text]GS/s. The 4-bit, 20-GS/s flash ADC is realized in 0.13-[Formula: see text]m SiGe BiCMOS technology and it only occupies 1.05[Formula: see text]mm[Formula: see text][Formula: see text][Formula: see text]1.46[Formula: see text]mm chip area. With a power consumption of 1.831[Formula: see text]W from 4-V supply, the ADC achieves an effective number of bits (ENOB) of 2.5 at 15[Formula: see text]GS/s.
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Fargette, D., A. Pinel, M. Rakotomalala, E. Sangu, O. Traoré, D. Sérémé, F. Sorho, et al. "Rice Yellow Mottle Virus, an RNA Plant Virus, Evolves as Rapidly as Most RNA Animal Viruses." Journal of Virology 82, no. 7 (January 16, 2008): 3584–89. http://dx.doi.org/10.1128/jvi.02506-07.
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ABSTRACT The rate of evolution of an RNA plant virus has never been estimated using temporally spaced sequence data, by contrast to the information available on an increasing range of animal viruses. Accordingly, the evolution rate of Rice yellow mottle virus (RYMV) was calculated from sequences of the coat protein gene of isolates collected from rice over a 40-year period in different parts of Africa. The evolution rate of RYMV was estimated by pairwise distance linear regression on five phylogeographically defined groups comprising a total of 135 isolates. It was further assessed from 253 isolates collected all over Africa by Bayesian coalescent methods under strict and relaxed molecular clock models and under constant size and skyline population genetic models. Consistent estimates of the evolution rate between 4 × 10−4 and 8 × 10−4 nucleotides (nt)/site/year were obtained whatever method and model were applied. The synonymous evolution rate was between 8 × 10−4 and 11 × 10−4 nt/site/year. The overall and synonymous evolution rates of RYMV were within the range of the rates of 50 RNA animal viruses, below the average but above the distribution median. Experimentally, in host change studies, substitutions accumulated at an even higher rate. The results show that an RNA plant virus such as RYMV evolves as rapidly as most RNA animal viruses. Knowledge of the molecular clock of plant viruses provides methods for testing a wide range of biological hypotheses.
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Goel, Gagan, Vahab Mirrokni, and Renato Paes Leme. "Pareto Efficient Auctions with Interest Rates." Proceedings of the AAAI Conference on Artificial Intelligence 33 (July 17, 2019): 1989–95. http://dx.doi.org/10.1609/aaai.v33i01.33011989.
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We consider auction settings in which agents have limited access to monetary resources but are able to make payments larger than their available resources by taking loans with a certain interest rate. This setting is a strict generalization of budget constrained utility functions (which corresponds to infinite interest rates). Our main result is an incentive compatible and Pareto-efficient auction for a divisible multi-unit setting with 2 players who are able to borrow money with the same interest rate. The auction is an ascending price clock auction that bears some similarities to the clinching auction but at the same time is a considerable departure from this framework: allocated goods can be de-allocated in future and given to other agents and prices for previously allocated goods can be raised.
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Anderson-Gold, Sharon. "Privacy, Respect and the Virtues of Reticence in Kant." Kantian Review 15, no. 2 (July 2010): 28–42. http://dx.doi.org/10.1017/s1369415400002429.
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At a time when the public is increasingly exposed to public scandals, moral defences of privacy are hard to come by. Privacy, it is argued, is merely a cloak for deception and vice. Since the virtuous have nothing to hide, full disclosure of ourselves to others must be a moral obligation. Given the rigour with which Kant defends the prohibition on lying, many have inferred that Kantian ethics must be equally strict on the necessity of truth telling. Do we in fact owe others the truth, the whole truth and nothing but the truth?
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Beaulé, Christian, Daniel Granados-Fuentes, Luciano Marpegan, and Erik D. Herzog. "In vitro circadian rhythms: imaging and electrophysiology." Essays in Biochemistry 49 (June 30, 2011): 103–17. http://dx.doi.org/10.1042/bse0490103.
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In vitro assays have localized circadian pacemakers to individual cells, revealed genetic determinants of rhythm generation, identified molecular players in cell–cell synchronization and determined physiological events regulated by circadian clocks. Although they allow strict control of experimental conditions and reduce the number of variables compared with in vivo studies, they also lack many of the conditions in which cellular circadian oscillators normally function. The present review highlights methods to study circadian timing in cultured mammalian cells and how they have shaped the hypothesis that all cells are capable of circadian rhythmicity.
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Hartstein, Lauren, Lameese Akacem, Cecilia Diniz Behn, Shelby Stowe, Kenneth Wright, and Monique LeBourgeois. "156 Evening Light-Induced Circadian Phase Shift in Preschool-Aged Children." Sleep 44, Supplement_2 (May 1, 2021): A63—A64. http://dx.doi.org/10.1093/sleep/zsab072.155.
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Abstract Introduction In adults, exposure to light at night delays the timing of the circadian clock in a dose-dependent manner with intensity. Although children’s melatonin levels are highly suppressed by evening bright light, the sensitivity of young children’s circadian timing to evening light is unknown. This research aimed to establish an illuminance response curve for phase delay in preschool children as a result of exposure to varying light intensities in the hour before bedtime. Methods Healthy children (n=36, 3.0 – 4.9 years, 39% males), participated in a 10-day protocol. For 7 days, children followed a strict parent-selected sleep schedule. On Days 8-10, an in-home dim-light assessment was performed. On Day 8, dim light melatonin onset (DLMO) was measured through saliva samples collected in 20-30-min intervals throughout the evening until 1-h past habitual bedtime. On Day 9, children were exposed to a white light stimulus (semi-randomly assigned from 5lx to 5000lx) for 1-h before their habitual bedtime, and saliva was collected before, during, and after the exposure. On Day 10, children provided saliva samples in the evening for 2.5-h past bedtime for a final DLMO assessment. Phase angle of entrainment (habitual bedtime – DLMObaseline) and circadian phase delay (DLMOfinal – DLMObaseline) were computed. Results Final DLMO (Day 10) shifted between -8 and 123 minutes (M = 56.1 +/- 33.6 min; negative value = phase advance, positive value = phase delay) compared with DLMO at baseline (Day 8). Raw phase shift did not demonstrate a dose-dependent relationship with light intensity. Rather, we observed a robust phase delay across all intensities. Conclusion These data suggest preschoolers’ circadian clocks are immensely sensitive to a large range of light intensities, which may be mechanistically influenced by less mature ophthalmologic features (e.g. clearer lenses, larger pupils). With young children’s ever-growing use of light-emitting devices and evening exposure to artificial lighting, as well as the prevalence of behavioral sleep problems, these findings may inform recommendations for parents on the effects of evening light exposure on sleep timing in early childhood. Support (if any) This research was supported with funds from the Eunice Kennedy Shriver National Institute of Child Health & Human Development (R01-HD087707).
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Ng, David. "Wearable smart device incorporating real-time clock module and alcohol sensor." KnE Engineering 2, no. 2 (February 9, 2017): 328. http://dx.doi.org/10.18502/keg.v2i2.633.
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<p>In this work, we designed and built a wearable device with battery-saving and alcohol-sensing functions. The motivation for this device was to deliver a proof-of-concept wearable and functional device which alerts the user of possible alcohol breath level above a threshold limit and can be worn for an extended time due to battery saving features. It was built using a combination of Arduino electronics and sensors, and encased in 3D-printed ABS bracelet. A 4-digit 7-segment LED display on board is used to display time which is tracked using a real-time clock module. A 3-axis accelerometer determines the orientation of the device and activates the display only when it is held in a specific orientation by the user. An example is when two axes are normal to the gravitational pull while a single axis is in line with gravity to simulate users raising their arm parallel to the ground. A slight tolerance in the setting ensures that the threshold for activation is not overly strict. This will ensure that the LED display is activated over a narrow range of orientations. The alcohol sensor is sensitive to alcohol content in the air. The threshold for detection can be changed and calibrated to the user specific needs. The alcohol sensor is slightly sensitive to humidity and very sensitive to alcohol. It has been tested with ethanol, wine and beer with 95%, 12.5% and 4.55% alcohol content, respectively. Because the alcohol sensor works by using a resistor that continuously pulls current and detects changes in resistivity due to adsorption of alcohol molecules, it consumes a lot of power when turned on continuously. In order to conserve power, the sensor can be activated only when the device is oriented in a specific position or when the user pushes a button. An Arduino Nano board is used to reduce the overall size of the device. It is powered using an external 5V battery via a mini-USB connector. In order to reduce the number of IO pins used, the RTC, LED and accelerometer were configured to use I2C interface connections. A default SCL clock speed of 100 kHz is used and the component IOs are connected to a common SDA line which terminates at one analog pin. In normal operation, the RTC is configured to read time continuously at one second interval. It is preprogramed with the correct date and time prior to operation of the device.</p>
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Ding, Hanqing, Qing Zhang, Yifeng Yin, Yong Gan, and Weihua Liu. "Research on Lightweight Mutual Authentication for the Product Authorization Chain." Security and Communication Networks 2021 (September 8, 2021): 1–9. http://dx.doi.org/10.1155/2021/8852901.
Full textAbstract:
With the development of the globalization economic integration in Internet of Things (IoT), it is very crucial to protect the wireless two-way authentication between users’ intelligent terminals and servers in the product authorization chain. In order to ensure that legitimate users connect to the wireless network correctly, a lightweight wireless mutual authentication scheme for the product authorization chain was proposed contrapose to the security defect of Kaul and Awasthi’s scheme, which easily suffered from offline password guessing attack. The improved scheme uses lightweight hash function and verifies the freshness of messages by using the send packet sequence number instead of timestamp, which can avoid strict clock synchronization between devices, and user passwords can be updated by themselves. Security analysis and cost and efficiency analysis show that the scheme presented in this paper has higher security, lower storage and communication costs, and lower computational complexity.
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Bahsis, Lahoucine, Hicham Ben El Ayouchia, Hafid Anane, Carmen Ramirez de Arellano, Abdeslem Bentama, El El Hadrami, Miguel Julve, Luis Domingo, and Salah-Eddine Stiriba. "Clicking Azides and Alkynes with Poly(pyrazolyl)borate-Copper(I) Catalysts: An Experimental and Computational Study." Catalysts 9, no. 8 (August 14, 2019): 687. http://dx.doi.org/10.3390/catal9080687.
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The synthesis of 1,4-disubstituted-1,2,3-triazoles under a copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) regime was accomplished in high yields and a regioselective manner by using two homoscorpionate poly(pyrazolyl)borate anions: tris(pyrazolyl)hydroborate (HB(pz)3−) and bis(pyrazolyl)hydroborate (H2B(pz)2−), which stabilized in situ the catalytically active copper (I) center. The [3+2] cycloaddition (32CA) reactions took place under strict click conditions, including room temperature and a mixture of environmentally benign solvents such as water/ethanol in a 1:1 (v/v) ratio. These click chemistry conditions were applied to form complex 1,2,3-triazoles-containing sugar moieties, which are potentially relevant from a biological point of view. Computational modeling carried out by DFT methodologies at the B3LYP/6-31G(d) level showed that the coordination of poly(pyrazolyl)borate-copper(I) to alkyne groups produced relevant changes in terms of generating a high polar copper(I)-acetylide intermediates. The analysis of the global and local reactivity indices explains correctly the role of poly(pyrazolyl)borate ligands in the stabilization and activation of the copper(I) catalyst in the studied 32CA reactions.
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Altschuler, Sari, and Aaron M. Tobiason. "Playbill for George Lippard's The Quaker City." PMLA/Publications of the Modern Language Association of America 129, no. 2 (March 2014): 267–73. http://dx.doi.org/10.1632/pmla.2014.129.2.267.
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On 11 november 1844, a Mob gathered outside philadelphia's chesnut street theatre for, in the words of the theater's manager, Francis Wemyss, the purpose “of a grand row” (395). The crowd intended to prevent the opening of The Quaker City; or, The Monks of Monk Hall, a play George Lippard had adapted from the work he was simultaneously publishing serially; it would become the best-selling novel of the first half of the nineteenth century. Capitalizing on a sensational 1843 murder case that fascinated Philadelphians, the novel retold the story of Singleton Mercer, a Philadelphia clerk acquitted of killing his sister's seducer. Infuriated by the playbill, Mercer attempted to purchase two hundred tickets for his supporters, who threatened to destroy the theater (Durang 247). Wemyss wanted Mercer jailed, but the mayor, wary of “riot and bloodshed,” countered, “I really think you have struck the first blow in your playbill” and called for the play's cancellation (qtd. in Wemyss 319-20). As the crowd of irate Philadelphians gathered, Lippard strode through it draped in an “ample cloak and carrying a sword-cane to repel assaults” (Bouton 20). Facing the very real prospect of violence, Wemyss reluctantly canceled the production.
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Bansal, Neha, and Ved Prakash Bansal. "Why is E-Commerce a Success Story in India?" VEETHIKA-An International Interdisciplinary Research Journal 2, no. 2 (June 30, 2016): 15–21. http://dx.doi.org/10.48001/veethika.2016.02.02.003.
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E-commerce a term we all know, we all are familiar or perhaps we come across daily, electronic marketing. A word that creating buzz everywhere in town. Perhaps is making our life’s too easy that now accepting life without it is a strict no case. Indian markets an expanding drastically in this area due to easiest, smartest and fastest marketing, to which we all called as just a click marketing. With a growing number of aspiring rural and urban internet-connected customers, there is a tremendous scope of online selling. There is a huge one-time customer base in India. This paper is an attempt to analyses the growth pattern in e-commerce, together with future upcoming trends.
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Yang, Xiuli, Yanhong Huang, Jianqi Shi, and Zongyu Cao. "A Performance Analysis Framework of Time-Triggered Ethernet Using Real-Time Calculus." Electronics 9, no. 7 (July 3, 2020): 1090. http://dx.doi.org/10.3390/electronics9071090.
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With increasing demands of deterministic and real-time communication, network performance analysis is becoming an increasingly important research topic in safety-critical areas, such as aerospace, automotive electronics and so on. Time-triggered Ethernet (TTEthernet) is a novel hybrid network protocol based on the Ethernet standard; it is deterministic, synchronized and congestion-free. TTEthernet with a time-triggered mechanism meets the real-time and reliability requirements of safety-critical applications. Time-triggered (TT) messages perform strict periodic scheduling following the offline schedule tables. Different scheduling strategies have an effect on the performance of TTEthernet. In this paper, a performance analysis framework is designed to analyze the end-to-end delay, backlog bounds and resource utilization of network by real-time calculus. This method can be used as a base for the performance evaluation of TTEthernet scheduling. In addition, this study discusses the impacts of clock synchronization and traffic integration strategies on TT traffic in the network. Finally, a case study is presented to prove the feasibility of the performance analysis framework.
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Nazé, Yaël, Gregor Rauw, Stefan Czesla, Laurent Mahy, and Fran Campos. "Variations on a theme: the puzzling behaviour of Schulte 12." Astronomy & Astrophysics 627 (July 2019): A99. http://dx.doi.org/10.1051/0004-6361/201935141.
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One of the first massive stars detected in X-rays, Schulte 12 has remained a puzzle in several aspects. In particular, its extreme brightness both in the visible and X-ray ranges is intriguing. Thanks to Swift and XMM-Newton observations covering ∼5000 d, we report the discovery of a regular 108 d modulation in X-ray flux of unknown origin. The minimum in the high-energy flux appears due to a combination of increased absorption and decreased intrinsic emission. We examined in parallel the data from a dedicated spectroscopic and photometric monitoring in the visible and near-IR domains, complemented by archives. While a similar variation timescale is found in those data, they do not exhibit the strict regular clock found at high energies. Changes in line profiles cannot be related to binarity but rather correspond to non-radial pulsations. Considering the substantial revision of the distance of Schulte 12 from the second Gaia data release, the presence of such oscillations agrees well with the evolutionary status of Schulte 12, as it lies in an instability region of the HR diagram.
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McLay, Todd G. B., Michael J. Bayly, and Pauline Y. Ladiges. "Is south-western Western Australia a centre of origin for eastern Australian taxa or is the centre an artefact of a method of analysis? A comment on Hakea and its supposed divergence over the past 12 million years." Australian Systematic Botany 29, no. 2 (2016): 87. http://dx.doi.org/10.1071/sb16024.
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Lamont et al. (2016) concluded that the Australian sclerophyllous genus Hakea (Proteaceae) arose 18million years ago in the South West of Western Australia (SWA) and dispersed 18 times to eastern (EA) and central Australia (CA) only 12million years ago (mid-Miocene). Their explanation of the biogeographic history of Hakea was based on the following: accepting a fully resolved molecular phylogenetic tree, although ~40% of nodes had posterior probability values below 0.95; using all nodes including geographically paralogous nodes to determine ancestral area probabilities; and applying a strict clock to estimate clade divergence times. Our re-analyses of the same dataset using a relaxed clock model pushes the age of Hakea to 32.4 (21.8–43.7) million years ago relative to its nearest outgroups, and the age of the divergence of two major clades (A and B) to 24.7 (17.2–33.7) million years ago. Calibration based on a new finding of Late Cretaceous fossil Banksia pushes these dates to 48.0 (24.3–75.2) million years ago and 36.6 (18.5–55.4) million years ago respectively. We confirm that each of the two main clades includes lineages in SWA, CA and EA. At the basal node of Clade A, two eastern Australian species form the sister group to three SWA scrub–heath–Eremaean species. These two groups together are sister to a large, mostly unresolved clade of SWA, CA and EA taxa. Similarly, at the base of Clade B is a polytomy of lineages from the SWA, CA and EA, with no resolution of area relationships. There is no evidence of a centre of origin and diversification of the genus is older than the mid-Miocene, being at least Oligocene, and probably older, although calibration points for molecular dating are too far removed from the ingroup to provide any great confidence in the methodology. Consideration should be given to the possibility of vicariance of multiple, widespread ancestral lineages as an explanation for lineages now disjunct between EA and SWA.
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Taylor, J. C. "Computer Programs for Standardless Quantitative Analysis of Minerals Using the Full Powder Diffraction Profile." Powder Diffraction 6, no. 1 (March 1991): 2–9. http://dx.doi.org/10.1017/s0885715600016778.
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AbstractA Fortran 77 computer program has been developed for the quantitative analysis of minerals by multiphase profile analysis of the complete powder diffraction pattern. Featured are full-matrix least-squares refinement of 14 Rietveld “instrumental parameters” (phase scales, asymmetry, preferred orientations (March model), linewidths, instrument zero, lineshapes and unit cell dimensions), Brindley particle absorption contrast factors and amorphicity corrections. The program uses a crystal structure Databank, which contains information on absorption coefficients, unit cell data and crystal structures for some 90 common minerals. New minerals can be easily added. Structure parameters are also refinable by a profile decomposition method using a program called STRUCT. The sum of the calculated patterns, derived from the crystal structure data, is fitted to the observed pattern by a program called TRACSCAL which runs in singlepass multiphase mode and, after the above corrections have been applied, the weight percentages of the component phases are calculated from the Rietveld scaling factors.The program runs on an IBM-compatible AT computer with 640K of RAM, on an extended memory AT, or a mainframe system. Examples of its use are given with standard mixtures and naturally occurring specimens. On an AT computer with 20MHz clock speed a scaling run, including data input, reading of the pattern, processing of (hkl) files, calculation of the profile and one cycle of least squares fitting takes about 30 seconds for binary standard mixtures and about 2.5 minutes for a 7-phase natural bauxite pattern containing 320 independent (hkl) reflections.
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Aydogdu, Canan, Henk Wymeersch, Olof Eriksson, Hans Herbertsson, and Mats Rydström. "Synchronization-Free RadChat for Automotive Radar Interference Mitigation." Sustainability 13, no. 12 (June 18, 2021): 6891. http://dx.doi.org/10.3390/su13126891.
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Automotive radar interference mitigation is expected to be inherent in all future ADAS and AD vehicles. Joint radar communications is a candidate technology for removing this interference by coordinating radar sensing through communication. Coordination of radars requires strict time synchronization among vehicles, and our formerly proposed protocol (RadChat) achieves this by a precise absolute time, provided by GPS clocks of vehicles. However, interference might appear if synchronization among vehicles is lost in case GPS is spoofed, satellites are blocked over short intervals, or GPS is restarted/updated. Here we present a synchronization-free version of RadChat (Sync-free RadChat), which relies on using the relative time for radar coordination, eliminating the dependency on the absolute time provided by GPS. Simulation results obtained for various use cases show that Sync-free RadChat is able to mitigate interference without degrading the radar performance.
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Nurlaila, Qomarotun. "Analisa Pengaruh Pengaturan Kerja Operator Terhadap Pencapaian Keluaran Produksi." Jurnal Sistem dan Manajemen Industri 1, no. 1 (August 5, 2017): 49. http://dx.doi.org/10.30656/jsmi.v1i1.172.
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PT. XYZ is a manufacturing company that produces the constituent components of HDD (Hard Disk Drive) products. One of the products produced by PT. XYZ made from rubber. The product has a strict specification, both for the accuracy of size and for display. One of the problems faced by PT. XYZ is the output of a 100% unstable check section even though the amount of human resources used is the same every day. There is a variation of the output / clock / operator from 650 to 714.4 pieces. This study aims to analyze the cause of the variation of output / hour / operator and to find solutions to minimize the output variation. The result of this research can be concluded that the cause of variation of output / hour / operator is the number of product type checked by operator not always the same every day. Where more and more types of products are checked then the smaller the output on that day. To get maximum results then the operator only do one type of product every day. If not possible then cultivated to a minimum operator change the type of product checked. It requires expertise from the supervisor to manage the work of the operator in an effort to get the maximum output.
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Zhan, Yinhu, Shaojie Chen, and Donghan He. "High-Precision Heading Determination Based on the Sun for Mars Rover." Advances in Astronomy 2018 (August 1, 2018): 1–14. http://dx.doi.org/10.1155/2018/1493954.
Full textAbstract:
Since the American Mars Exploration Rover Opportunity landed on Mars in 2004, it has travelled more than 40 km, and heading-determination technology based on its sun sensor has played an important role in safe driving of the rover. A high-precision heading-determination method will always play a significant role in the rover’s autonomous navigation system, and the precision of the measured heading strongly affects the navigation results. In order to improve the heading precision to the 1-arcminute level, this paper puts forward a novel calibration algorithm for solving the comparable distortion of large-field sun sensor by introducing an antisymmetric matrix. The sun sensor and inclinometer alignment model are then described in detail to maintain a high-precision horizon datum, and a strict sun image centroid-extraction algorithm combining subpixel edge detection with circle or ellipse fitting is presented. A prototype comprising a sun sensor, electronic inclinometer, and chip-scale atomic clock is developed for testing the algorithms, models, and methods presented in this paper. Three field tests were conducted in different months during 2017. The results show that the precision of the heading determination reaches 0.28–0.97′ (1σ) and the centroid error of the sun image and the sun elevation are major factors that affect the heading precision.
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Tian, Ruyun, Junjie Zhang, Shuai Zhang, Longxu Wang, Hongyuan Yang, Yuda Chen, Yuanjie Jiang, Jun Lin, and Linhang Zhang. "A High-Precision Energy-Efficient GPS Time-Sync Method for High-Density Seismic Surveys." Applied Sciences 10, no. 11 (May 29, 2020): 3768. http://dx.doi.org/10.3390/app10113768.
Full textAbstract:
Large numbers of seismic channels and high-density energy-efficient acquisition systems are the development trend of seismic instruments and have attracted high R&D interests in recent years. The combination of remote sensing and wireless sensor network technology provides superior observation capabilities for high-density seismic exploration. However, large-scale and multi-node acquisition methods place higher requirements on time synchronization performance. Seismic data with poor time synchronization will cause considerable errors in the interpretation of seismic data and even have no practical significance. Thus, the strict time synchronization performance is the prerequisite and basis for the application of cable-less storage seismograph in high-density seismic array applications. The existing time synchronization methods have high power consumption and poor time synchronization accuracy, which is not suitable for the long-time task. In addition, these methods are affected by the number of nodes and the distance. This paper presents an energy-efficient time-sharing indexed interpolation intercept method for the seismic data synchronization. The time synchronization method uses the high-precision TCXO as the main clock and records GPS time in the SD card at intervals to achieve the high-precision time-stamp for the seismic data. Then the seismic data is intercepted intermittently based on precise time stamps, which achieves the strict seismic data synchronization. Performance analysis shows that the time synchronization accuracy of the proposed method is 0.6 μs and saves 73% energy of the time-sync periods compared to the common GPS timing method. The field measurement results indicate that the time synchronization accuracy is not associated with the working time and the distance between nodes so that the proposed synchronization method is suitable for the high-density seismic survey.
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Mello, Beatriz, and Carlos G. Schrago. "The Estimated Pacemaker for Great Apes Supports the Hominoid Slowdown Hypothesis." Evolutionary Bioinformatics 15 (January 2019): 117693431985598. http://dx.doi.org/10.1177/1176934319855988.
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The recent surge of genomic data has prompted the investigation of substitution rate variation across the genome, as well as among lineages. Evolutionary trees inferred from distinct genomic regions may display branch lengths that differ between loci by simple proportionality constants, indicating that rate variation follows a pacemaker model, which may be attributed to lineage effects. Analyses of genes from diverse biological clades produced contrasting results, supporting either this model or alternative scenarios where multiple pacemakers exist. So far, an evaluation of the pacemaker hypothesis for all great apes has never been carried out. In this work, we tested whether the evolutionary rates of hominids conform to pacemakers, which were inferred accounting for gene tree/species tree discordance. For higher precision, substitution rates in branches were estimated with a calibration-free approach, the relative rate framework. A predominant evolutionary trend in great apes was evidenced by the recovery of a large pacemaker, encompassing most hominid genomic regions. In addition, the majority of genes followed a pace of evolution that was closely related to the strict molecular clock. However, slight rate decreases were recovered in the internal branches leading to humans, corroborating the hominoid slowdown hypothesis. Our findings suggest that in great apes, life history traits were the major drivers of substitution rate variation across the genome.
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Vaqueiro Ramos, Ana Luiza, Anna Julia Coutinho, Anna Julia Lemos de Moura, Bárbara Beatriz Michelini, Daniel Martinez, Natalia Sanmiguel, Idiberto Jose Zotarelli-Filho, Ana Valéria Garcia Ramirez, and Durval Ribas Filho. "Chronobiology: Proper Feeding to Sleep Cycles." MedNEXT Journal of Medical and Health Sciences 1, no. 1 (November 16, 2020): 8–14. http://dx.doi.org/10.34256/mdnt2012.
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Chronobiology is the process that studies the biological rhythms of living beings, in which each organism has its own biological clock. Sleep is a state of unconsciousness, characterized by the active inhibitory process, and that has an important relationship with feeding, mainly due to the possibility of sleep privation increasing starvation through hormonal regulation. In addition, starvation can lead to obesity, contributing to the risk factors for chronic non-communicable diseases, such as high blood pressure, hypercholesterolemia, diabetes mellitus, cardiovascular diseases, and some forms of cancer. The cycle of bad sleep may cause direct health problems, such as the diseases mentioned above; and indirect, may result in traffic accidents, unemployment, and difficulties in interpersonal relationships, with the possibility of progressing to anxiety disorders. This study aims to analyze whether there is a relationship between healthy eating and the standard of sleep quality, providing better performance of daily activities. For this study, the 133 participants answered 3 feeding records and, later, questionnaires on sleep quality (Pittsburgh Sleep Quality Index) in three moments. Considering the three questionnaires, there were no significant differences obtained by calculating the statistical tests, however, the analysis of the gross medians with the proposed score showed a strict relationship between sleep and food. In addition to the relationship between food and sleep quality, other factors such as stress and anxiety can contribute to hormonal dysregulation, thus changing the pattern of sleep quality of individuals.
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Wieczorek, D. F., M. Periasamy, G. S. Butler-Browne, R. G. Whalen, and B. Nadal-Ginard. "Co-expression of multiple myosin heavy chain genes, in addition to a tissue-specific one, in extraocular musculature." Journal of Cell Biology 101, no. 2 (August 1, 1985): 618–29. http://dx.doi.org/10.1083/jcb.101.2.618.
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We have investigated the developmental transitions of myosin heavy chain (MHC) gene expression in the rat extraocular musculature (EOM) at the mRNA level using S1-nuclease mapping techniques and at the protein level by polypeptide mapping and immunochemistry. We have isolated a genomic clone, designated lambda 10B3, corresponding to an MHC gene which is expressed in the EOM fibers (recti and oblique muscles) of the adult rat but not in hind limb muscles. Using cDNA and genomic probes for MHC genes expressed in skeletal (embryonic, neonatal, fast oxidative, fast glycolytic, and slow/cardiac beta-MHC), cardiac (alpha-MHC), and EOM (lambda 10B3) muscles, we demonstrate the concomitant expression at the mRNA level of at least six different MHC genes in adult EOM. Protein and immunochemical analyses confirm the presence of at least four different MHC types in EOM. Immunocytochemistry demonstrates that different myosin isozymes tend to segregate into individual myofibers, although some fibers seem to contain more than one MHC type. The results also show that the EOM fibers exhibit multiple patterns of MHC gene regulation. One set of fibers undergoes a sequence of isoform transitions similar to the one described for limb skeletal muscles, whereas other EOM myofiber populations arrest the MHC transition at the embryonic, neonatal/adult, or adult EOM-specific stage. Thus, the MHC gene family is not under the control of a strict developmental clock, but the individual genes can modify their expression by tissue-specific and/or environmental factors.
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Arcila-Galvis, Juliana E., Rafael E. Arango, Javier M. Torres-Bonilla, and Tatiana Arias. "The Mitochondrial Genome of a Plant Fungal Pathogen Pseudocercospora fijiensis (Mycosphaerellaceae), Comparative Analysis and Diversification Times of the Sigatoka Disease Complex Using Fossil Calibrated Phylogenies." Life 11, no. 3 (March 9, 2021): 215. http://dx.doi.org/10.3390/life11030215.
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Mycosphaerellaceae is a highly diverse fungal family containing a variety of pathogens affecting many economically important crops. Mitochondria play a crucial role in fungal metabolism and in the study of fungal evolution. This study aims to: (i) describe the mitochondrial genome of Pseudocercospora fijiensis, and (ii) compare it with closely related species (Sphaerulina musiva, S. populicola, P. musae and P. eumusae) available online, paying particular attention to the Sigatoka disease’s complex causal agents. The mitochondrial genome of P. fijiensis is a circular molecule of 74,089 bp containing typical genes coding for the 14 proteins related to oxidative phosphorylation, 2 rRNA genes and a set of 38 tRNAs. P. fijiensis mitogenome has two truncated cox1 copies, and bicistronic transcription of nad2-nad3 and atp6-atp8 confirmed experimentally. Comparative analysis revealed high variability in size and gene order among selected Mycosphaerellaceae mitogenomes likely to be due to rearrangements caused by mobile intron invasion. Using fossil calibrated Bayesian phylogenies, we found later diversification times for Mycosphaerellaceae (66.6 MYA) and the Sigatoka disease complex causal agents, compared to previous strict molecular clock studies. An early divergent Pseudocercospora fijiensis split from the sister species P. musae + P. eumusae 13.31 MYA while their sister group, the sister species P. eumusae and P. musae, split from their shared common ancestor in the late Miocene 8.22 MYA. This newly dated phylogeny suggests that species belonging to the Sigatoka disease complex originated after wild relatives of domesticated bananas (section Eumusae; 27.9 MYA). During this time frame, mitochondrial genomes expanded significantly, possibly due to invasions of introns into different electron transport chain genes.
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Ankrum, Andrea, and Barry G. Hall. "Population Dynamics of Staphylococcus aureus in Cystic Fibrosis Patients To Determine Transmission Events by Use of Whole-Genome Sequencing." Journal of Clinical Microbiology 55, no. 7 (April 26, 2017): 2143–52. http://dx.doi.org/10.1128/jcm.00164-17.
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ABSTRACT Strict infection control practices have been implemented for health care visits by cystic fibrosis (CF) patients in an attempt to prevent transmission of important pathogens. This study used whole-genome sequencing (WGS) to determine strain relatedness and assess population dynamics of Staphylococcus aureus isolates from a cohort of CF patients as assessed by strain relatedness. A total of 311 S. aureus isolates were collected from respiratory cultures of 115 CF patients during a 22-month study period. Whole-genome sequencing was performed, and using single nucleotide polymorphism (SNP) analysis, phylogenetic trees were assembled to determine relatedness between isolates. Methicillin-resistant Staphylococcus aureus (MRSA) phenotypes were predicted using PPFS2 and compared to the observed phenotype. The accumulation of SNPs in multiple isolates obtained over time from the same patient was examined to determine if a genomic molecular clock could be calculated. Pairs of isolates with ≤71 SNP differences were considered to be the “same” strain. All of the “same” strain isolates were either from the same patient or siblings pairs. There were 47 examples of patients being superinfected with an unrelated strain. The predicted MRSA phenotype was accurate in all but three isolates. Mutation rates were unable to be determined because the branching order in the phylogenetic tree was inconsistent with the order of isolation. The observation that transmissions were identified between sibling patients shows that WGS is an effective tool for determining transmission between patients. The observation that transmission only occurred between siblings suggests that Staphylococcus aureus acquisition in our CF population occurred outside the hospital environment and indicates that current infection prevention efforts appear effective.
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Norström, Melissa M., Marcus Buggert, Johanna Tauriainen, Wendy Hartogensis, Mattia C. Prosperi, Mark A. Wallet, Frederick M. Hecht, Marco Salemi, and Annika C. Karlsson. "Combination of Immune and Viral Factors Distinguishes Low-Risk versus High-Risk HIV-1 Disease Progression in HLA-B*5701 Subjects." Journal of Virology 86, no. 18 (July 3, 2012): 9802–16. http://dx.doi.org/10.1128/jvi.01165-12.
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HLA-B*5701 is the host factor most strongly associated with slow HIV-1 disease progression, although rates can vary within this group. Underlying mechanisms are not fully understood but likely involve both immunological and virological dynamics. The present study investigated HIV-1in vivoevolution and epitope-specific CD8+T cell responses in six HLA-B*5701 patients who had not received antiretroviral treatment, monitored from early infection for up to 7 years. The subjects were classified as high-risk progressors (HRPs) or low-risk progressors (LRPs) based on baseline CD4+T cell counts. Dynamics of HIV-1 Gag p24 evolution and multifunctional CD8+T cell responses were evaluated by high-resolution phylogenetic analysis and polychromatic flow cytometry, respectively. In all subjects, substitutions occurred more frequently in flanking regions than in HLA-B*5701-restricted epitopes. In LRPs, p24 sequence diversity was significantly lower; sequences exhibited a higher degree of homoplasy and more constrained mutational patterns than HRPs. The HIV-1 intrahost evolutionary rate was also lower in LRPs and followed a strict molecular clock, suggesting neutral genetic drift rather than positive selection. Additionally, polyfunctional CD8+T cell responses, particularly to TW10 and QW9 epitopes, were more robust in LRPs, who also showed significantly higher interleukin-2 (IL-2) production in early infection. Overall, the findings indicate that HLA-B*5701 patients with higher CD4 counts at baseline have a lower risk of HIV-1 disease progression because of the interplay between specific HLA-linked immune responses and the rate and mode of viral evolution. The study highlights the power of a multidisciplinary approach, integrating high-resolution evolutionary and immunological data, to understand mechanisms underlying HIV-1 pathogenesis.
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Homma, K., and J. W. Hastings. "Cell growth kinetics, division asymmetry and volume control at division in the marine dinoflagellate Gonyaulax polyedra: a model of circadian clock control of the cell cycle." Journal of Cell Science 92, no. 2 (February 1, 1989): 303–18. http://dx.doi.org/10.1242/jcs.92.2.303.
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A new method of determining the dependence of cell growth on the initial cell volume in the absence of cell division is presented. The assumptions are that volume in a certain period of time is either increasing or decreasing, but not both, and is independent of the history of cells. Applying this method to Gonyaulax polyedra in a 12h light-12h dark cycle, growth in volume between the 3rd and 12th hours of the light period is found to be more exponential-like than linear. The magnitude of growth in the time period is determined solely by cell volume and environmental conditions, not by cell age. All cells decrease in volume slightly in the dark from the 12th to 23rd hour, and then increase a little from the 23rd to 3rd hour of the following day. Cell division in this species is significantly asymmetric, and the extent of asymmetry is estimated mathematically. Simulations based on the growth patterns and the asymmetric division reveal that cell division must at least partly depend on the volume of cells. The dependence of conditional cell division probability on cell volume is then experimentally determined. The probability is zero up to a certain cell volume, and then it gradually increases to a plateau level, which is less than unity. Neither the strict size control model nor the transition probability model is fully consistent with the observed shape of the conditional probability function. A hybrid model postulating a ‘sloppy’ critical volume with a constant probability of division above that volume adequately accounts for the conditional probability. With the use of the observed volume growth law, cell division dependence on volume, and the extent of asymmetry in cell division, cell volume distributions are successfully simulated for cells growing in a 12h light-12h dark cycle. Another simulation reveals that the true coefficient of variation in generation time is 33%. On the basis of these findings, a model of the cell cycle is presented that incorporates the circadian clock as a cyclic G1 phase. According to this scheme, cells satisfying the minimum cell volume requirement between the 12th and the 18th hour probably exit to the replication/segregation sequence ending in division, and re-enter the cyclic portion after a fixed time interval.
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Portefaix, Lilian. "Ancient Ephesus: Processions as Media of Religious and Secular Propaganda." Scripta Instituti Donneriani Aboensis 15 (January 1, 1993): 195–210. http://dx.doi.org/10.30674/scripta.67212.
Full textAbstract:
The significance of religious rituals often reaches beyond their strict religious intentions. Specifically a procession, performed in front of the public, is a most effective instrument of disseminating a message to the crowds. Consequently, this ritual, as is well known, has often been used not only in religious but also in secular contexts; a procession under the cloak of religion can even become a politically useful medium to avoid popular disturbances on peaceful terms. This was the case in ancient Ephesus, where Roman power conflicted with Greek culture from the middle of the first century B.C. onwards. In the beginning of the second century A.D. the public religious life in the city of Ephesus was to a great extent characterized by processions relating to the cult of Artemis Ephesia. The one traditionally performed on the birthday of the goddess called to mind the Greek origin of the city; it was strictly associated with the religious sphere bringing about a close relationship between the goddess and her adherents. The other, artificially created by a Roman, was entirely secular, and spread its message every fortnight in the streets of Ephesus. It referred to the political field of action and intended to strengthen the Roman rule over the city. The Greek origin of Ephesian culture was later included in the message of the procession, reminding the Greeks not to rebel against Roman rule.
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Boothalingam, Sriram, Chris Allan, Prudence Allen, and David W. Purcell. "The Medial Olivocochlear Reflex Is Unlikely to Play a Role in Listening Difficulties in Children." Trends in Hearing 23 (January 2019): 233121651987094. http://dx.doi.org/10.1177/2331216519870942.
Full textAbstract:
The medial olivocochlear reflex (MOCR) has been implicated in several auditory processes. The putative role of the MOCR in improving speech perception in noise is particularly relevant for children who complain of listening difficulties (LiD). The hypothesis that the MOCR may be impaired in individuals with LiD or auditory processing disorder has led to several investigations but without consensus. In two related studies, we compared the MOCR functioning of children with LiD and typically developing (TD) children in the same age range (7–17 years). In Study 1, we investigated ipsilateral, contralateral, and bilateral MOCR using forward-masked click-evoked otoacoustic emissions (CEOAEs; n = 17 TD, 17 LiD). In Study 2, we employed three OAE types: CEOAEs ( n = 16 TD, 21 LiD), stimulus frequency OAEs ( n = 21 TD, 30 LiD), and distortion product OAEs ( n = 17 TD, 22 LiD) in a contralateral noise paradigm. Results from both studies suggest that the MOCR functioning is not significantly different between the two groups. Some likely reasons for differences in findings among published studies could stem from the lack of strict data quality measures (e.g., high signal-to-noise ratio, control for the middle ear muscle reflex) that were enforced in the present study. The inherent variability of the MOCR, the subpar reliability of current MOCR methods, and the heterogeneity in auditory processing deficits that underlie auditory processing disorder make detecting clinically relevant differences in MOCR function impractical using current methods.
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Walker, T. W. ""A Torture Machine": The Violent Story of Slavery and the Beginning of American Capitalism." Monthly Review 67, no. 6 (November 7, 2015): 58. http://dx.doi.org/10.14452/mr-067-06-2015-10_7.
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<div class="bookreview">Edward E. Baptist, <em>The Half Has Never Been Told: Slavery and the Making of American Capitalism </em>(New York: Basic Books, 2014), 528 pages, $35, hardcover.</div>For an estimated hundreds of thousands of people, including some 60,000 workers who had served notice to their bosses, April 15, 2015, was strike day—reportedly the largest mobilization of low-wage workers since May Day of 1886, when a half million workers and their families (10 percent of the population at the time) struck for the eight-hour work day. Hundreds of us from here in Tennessee joined fast food workers, adjuncts, and home and child-care workers in the morning for strike actions, and many of us boarded buses to St. Louis and Ferguson, Missouri, for a Black Lives Matter protest that brought together strikers and supporters from all across the region. It was an intense and exact showcase of the irrevocable knot of violent and permanent racism in this country, and its broadening (and racialized) wealth and income gap and the deepening, permanent poverty of working-class life.… There is no legitimate history of this nation's past and present that can deny the twin realities of extreme economic exploitation of people of color, especially African Americans, and the incredible violence perpetrated against them. Edward Baptist's <em>The Half Has Never Been Told</em> draws these two realities together in his contribution to the new set of histories of U.S. capitalism, slavery, and cotton, which include Sven Beckert's <em>Empire of Cotton</em> and Walter Johnson's <em>River of Dark Dreams</em>.<p class="mrlink"><p class="mrpurchaselink"><a href="http://monthlyreview.org/index/volume-67-number-6" title="Vol. 67, No. 6: November 2015" target="_self">Click here to purchase a PDF version of this article at the <em>Monthly Review</em> website.</a></p>
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Thapa, Vaskar, Gregory G. Turner, and Marilyn J. Roossinck. "Phylogeographic analysis of Pseudogymnoascus destructans partitivirus-pa explains the spread dynamics of white-nose syndrome in North America." PLOS Pathogens 17, no. 3 (March 17, 2021): e1009236. http://dx.doi.org/10.1371/journal.ppat.1009236.
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Understanding the dynamics of white-nose syndrome spread in time and space is an important component for the disease epidemiology and control. We reported earlier that a novel partitivirus, Pseudogymnoascus destructans partitivirus-pa, had infected the North American isolates of Pseudogymnoascus destructans, the fungal pathogen that causes white-nose syndrome in bats. We showed that the diversity of the viral coat protein sequences is correlated to their geographical origin. Here we hypothesize that the geographical adaptation of the virus could be used as a proxy to characterize the spread of white-nose syndrome. We used over 100 virus isolates from diverse locations in North America and applied the phylogeographic analysis tool BEAST to characterize the spread of the disease. The strict clock phylogeographic analysis under the coalescent model in BEAST showed a patchy spread pattern of white-nose syndrome driven from a few source locations including Connecticut, New York, West Virginia, and Kentucky. The source states had significant support in the maximum clade credibility tree and Bayesian stochastic search variable selection analysis. Although the geographic origin of the virus is not definite, it is likely the virus infected the fungus prior to the spread of white-nose syndrome in North America. We also inferred from the BEAST analysis that the recent long-distance spread of the fungus to Washington had its root in Kentucky, likely from the Mammoth cave area and most probably mediated by a human. The time to the most recent common ancestor of the virus is estimated somewhere between the late 1990s to early 2000s. We found the mean substitution rate of 2 X 10−3 substitutions per site per year for the virus which is higher than expected given the persistent lifestyle of the virus, and the stamping-machine mode of replication. Our approach of using the virus as a proxy to understand the spread of white-nose syndrome could be an important tool for the study and management of other infectious diseases.
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Yadav, Neetu, Kritesh Gupta, and Vibhor Khetrapal. "Next Education: Technology Transforming Education." South Asian Journal of Business and Management Cases 7, no. 1 (March 22, 2018): 68–77. http://dx.doi.org/10.1177/2277977918754443.
Full textAbstract:
The approach towards teaching and learning has drastically changed with the advent of technology. Classrooms are no longer what they used to be. The traditional spaces fitted with blackboards and controlled by overbearing/strict teachers have given way to the new-age ‘smart’ classrooms. The post-millennial generation, which is highly exposed to gadgets like smartphones, has a short attention span and seeks quick learning at the click of a button. They want the freedom to decide what and how they want to learn; this wish is fulfilled by technology that has democratized Indian education system. The integration of technology and education was seen as a thrust area for business development in the early 2000s. In 2007, two IIT alumni and serial entrepreneurs, Beas Dev Ralhan and Raveendranath Kamath, started Next Education with the aim of changing the face of education in India by melding it with technology. In a short span of 10 years, it reached over more than 10,000 schools across the country transforming lives of more than 1,000,000 students with its flagship products such as TeachNext, LearnNext, MathsLab, Next ERP and aims at becoming the leader in technology-based education solution provider. The journey has been quite challenging with stiff competition from EdTech market leaders and resistance from various stakeholders. The questions Ralhan and Kamath were facing: How to enter into an industry which was at the nascent stage? How to create its market space and how to sustain it? How to beat the challenges in establishing a foothold in technology-driven education industry?
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Kaknjo, Admir, Muzaffar Rao, Edin Omerdic, Luke Robinson, Daniel Toal, and Thomas Newe. "Real-Time Video Latency Measurement between a Robot and Its Remote Control Station: Causes and Mitigation." Wireless Communications and Mobile Computing 2018 (December 2, 2018): 1–19. http://dx.doi.org/10.1155/2018/8638019.
Full textAbstract:
This work presents a detailed study, characterization, and measurement of video latency in a real-time video streaming application. The target application consists of an automatic control system in the form of a control station and the mini Remotely Operated Vehicle (ROV) equipped with a camera, which is controllable over local area network (LAN) and the Internet. Control signal transmission and feedback measurements to the operator usually impose real-time constraints on the network channel. Similarly, the video stream, which is required for the normal system control and maneuvering, imposes further strict requirements on the network in terms of bandwidth and latency. Based on these requirements, controlling the system in real time through a standard Internet connection is a challenging task. The measurement of important network parameters like availability, bandwidth, and latency has become mandatory for remotely controlling the system in real time. It is necessary to establish a methodology for the measurement of video and network latency to improve the real-time controllability and safety of the system as such measurement is not possible using existing solutions due to the following reasons: insufficient accuracy, relying on the Internet resources such as generic Network Time Protocol (NTP) servers, inability to obtain one-way delay measurement, and many solutions only having support for web cameras. Here, an efficient, reliable, and cost-effective methodology for the measurement of latency of a video stream over a LAN and the Internet is proposed. A dedicated stratum-1 NTP server is used and the necessary software needed for acquiring and measuring the latency of a video stream from a generic IP camera as well as integration into the existing ROV control software was developed. Here, by using the software and dedicated clock synchronization equipment (NTP server), it was found that normal video latencies in a LAN were in the range of 488ms – 850ms, while latencies over the Internet were measured to be in the range of 558ms – 1211ms. It is important to note that the values were obtained by using a generic (off-the-shelf) IP camera and they represent the actual latencies which might be experienced during control over long range and across international territory borders.