Contact calls facilitate group contraction in free-ranging goats (Capra aegagrus hircus)

Many social animal species produce vocalizations believed to facilitate group contraction when one or more group members have become distant. However, the mechanisms underlying this function remain unclear for many species. We examined this question with data on a semi-free ranging group of 16 adult domesticated goats (Capra aegagrus hircus) inhabiting Tsaobis Nature Park, Namibia. All goats wore dataloggers consisting of a GPS and audio recorder for 5–6 h per day for 10 days, providing continuous data on their geolocations and vocal communication. We found that callers were farther from the group centroid than expected by chance and that call production was associated with the cessation of group expansion and subsequent group contraction. We did not find strong evidence for antiphonal call exchange between distant and core group members. Rather, we found that (i) call production by distant group members is associated with a significant reduction of group movement away from the caller, and (ii) call production by core group members is associated with greater, though not significantly greater, group movement toward the caller. These findings suggest that calls may be used by distant, and potentially core, group members to facilitate the contraction of group spread. Results from our study clarify the mechanisms through which social animals can regulate collective movement behavior and the specific role that vocalizations play in this process

Parallel Mechanisms for Visual Search in Zebrafish

This research was funded by project grant G1000053 from the National Centre for the Replacement, Reduction and Refinement of animals in research (NC3Rs; UK) and by the Medical Research Council (MRC; UK). CHB is a Royal Society (UK) Research Fellow

On the security of consumer wearable devices in the Internet of Things

Miniaturization of computer hardware and the demand for network capable devices has resulted in the emergence of a new class of technology called wearable computing. Wearable devices have many purposes like lifestyle support, health monitoring, fitness monitoring, entertainment, industrial uses, and gaming. Wearable devices are hurriedly being marketed in an attempt to capture an emerging market. Owing to this, some devices do not adequately address the need for security. To enable virtualization and connectivity wearable devices sense and transmit data, therefore it is essential that the device, its data and the user are protected. In this paper the use of novel Integrated Circuit Metric (ICMetric) technology for the provision of security in wearable devices has been suggested. ICMetric technology uses the features of a device to generate an identification which is then used for the provision of cryptographic services. This paper explores how a device ICMetric can be generated by using the accelerometer and gyroscope sensor. Since wearable devices often operate in a group setting the work also focuses on generating a group identification which is then used to deliver services like authentication, confidentiality, secure admission and symmetric key generation. Experiment and simulation results prove that the scheme offers high levels of security without compromising on resource demands

Bayesian Inference for Identifying Interaction Rules in Moving Animal Groups

The emergence of similar collective patterns from different self-propelled particle models of animal groups points to a restricted set of “universal” classes for these patterns. While universality is interesting, it is often the fine details of animal interactions that are of biological importance. Universality thus presents a challenge to inferring such interactions from macroscopic group dynamics since these can be consistent with many underlying interaction models. We present a Bayesian framework for learning animal interaction rules from fine scale recordings of animal movements in swarms. We apply these techniques to the inverse problem of inferring interaction rules from simulation models, showing that parameters can often be inferred from a small number of observations. Our methodology allows us to quantify our confidence in parameter fitting. For example, we show that attraction and alignment terms can be reliably estimated when animals are milling in a torus shape, while interaction radius cannot be reliably measured in such a situation. We assess the importance of rate of data collection and show how to test different models, such as topological and metric neighbourhood models. Taken together our results both inform the design of experiments on animal interactions and suggest how these data should be best analysed

Active Brownian Particles. From Individual to Collective Stochastic Dynamics

We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.Comment: 161 pages, Review, Eur Phys J Special-Topics, accepte

Association of trial registration with the results and conclusions of published trials of new oncology drugs

<p>Abstract</p> <p>Background</p> <p>Registration of clinical trials has been introduced largely to reduce bias toward statistically significant results in the trial literature. Doubts remain about whether advance registration alone is an adequate measure to reduce selective publication, selective outcome reporting, and biased design. One of the first areas of medicine in which registration was widely adopted was oncology, although the bulk of registered oncology trials remain unpublished. The net influence of registration on the literature remains untested. This study compares the prevalence of favorable results and conclusions among published reports of registered and unregistered randomized controlled trials of new oncology drugs.</p> <p>Methods</p> <p>We conducted a cross-sectional study of published original research articles reporting clinical trials evaluating the efficacy of drugs newly approved for antimalignancy indications by the United States Food and Drug Administration (FDA) from 2000 through 2005. Drugs receiving first-time approval for indications in oncology were identified using the FDA web site and Thomson Centerwatch. Relevant trial reports were identified using PubMed and the Cochrane Library. Evidence of advance trial registration was obtained by a search of clinicaltrials.gov, WHO, ISRCTN, NCI-PDQ trial databases and corporate trial registries, as well as articles themselves. Data on blinding, results for primary outcomes, and author conclusions were extracted independently by two coders. Univariate and multivariate logistic regression identified associations between favorable results and conclusions and independent variables including advance registration, study design characteristics, and industry sponsorship.</p> <p>Results</p> <p>Of 137 original research reports from 115 distinct randomized trials assessing 25 newly approved drugs for treating cancer, the 54 publications describing data from trials registered prior to publication were as likely to report statistically significant efficacy results and reach conclusions favoring the test drug (for results, OR = 1.77; 95% CI = 0.87 to 3.61) as reports of trials not registered in advance. In multivariate analysis, reports of prior registered trials were again as likely to favor the test drug (OR = 1.29; 95% CI = 0.54 to 3.08); large sample sizes and surrogate outcome measures were statistically significant predictors of favorable efficacy results at p < 0.05. Subgroup analysis of the main reports from each trial (n = 115) similarly indicated that registered trials were as likely to report results favoring the test drug as trials not registered in advance (OR = 1.11; 95% CI = 0.44 to 2.80), and also that large trials and trials with nonstringent blinding were significantly more likely to report results favoring the test drug.</p> <p>Conclusions</p> <p>Trial registration alone, without a requirement for full reporting of research results, does not appear to reduce a bias toward results and conclusions favoring new drugs in the clinical trials literature. Our findings support the inclusion of full results reporting in trial registers, as well as protocols to allow assessment of whether results have been completely reported.</p

The incidence of occult malignancy following uterine morcellation: A ten-year single institution experience retrospective cohort study.

INTRODUCTION: When the Food and Drug Administration (FDA) initially reported on the parlous incidence (0.28%) of occult malignancy identified following uterine power morcellation, investigations thereafter documented their particular experience with this surgical procedure. Nevertheless, the precise risk of identifying a sarcoma following uterine morcellation remains indeterminate, primarily due to varying study patient risk factors, diagnostic criteria and operative approach. METHOD: We retrospectively evaluated subjects who underwent an endoscopic hysterectomy and uterine power morcellation for the treatment of a presumptive, benign indication from January 2006 until December 2015. The primary outcome was the incidence of an occult malignancy. Secondarily, we were interested in characterizing the patients\u27 specific clinical (age, menopausal status, body mass index (BMI)) risk factors within the context of a confirmed malignant or pre-malignant pathology. RESULTS: We identified 281 patients who underwent endoscopic surgery that incorporated uterine morcellation. During the study period, one subject was ultimately diagnosed with a uterine leiomyosarcoma; the overall incidence of occult malignancy was 0.36%. There were also 3 cases of uterine premalignant disease on final pathology (2 patients had complex hyperplasia with or without atypia and 1 subject was diagnosed with a smooth muscle tumor of uncertain malignant potential (an incidence of 1.1%)). We were unable to establish any relationship between patient age, uterine weight, menopausal status or BMI and the incidence of a malignant or pre-malignant pathology (P \u3e 0.05). CONCLUSION: The rate of occult malignancy in the present investigation was similar to previously documented studies and that which has been reported by the FDA. Additional study of methods in which to enhance preoperative work-up and mitigate the surgical risk for tumor cell dissemination is warranted