Validating an automated classification system for snake movement behavior: refining and extending the radio telemetry-accelerometry framework

An animal’s behavioral decisions, such as when, why, and how individuals move through their environment, are mediated by a complex interplay between internal (e.g., sex, physiological state, motivational state) and external (e.g., environmental conditions, predation, competition) factors. A detailed understanding of the causes and consequences of these decisions for many species has historically been precluded by methodological constraints. However, a recent wave of advancements in sensor technologies circumvents many of these traditional limitations and has spurred the emerging field of biologging science. Animal-attached dataloggers (or biologgers) give researchers the ability to remotely monitor an individual’s physiology and behavior in the field at resolutions and precisions historically restricted to laboratories. Accelerometer dataloggers, specifically, are small (\u3c 1 g) piezo-electric (springlike) sensors that measure three-dimensional acceleration (upward, downward, and side-to-side) derived from subject motion, enabling interpretation of a wide range of movement-mediated behaviors. This project aims to expand on a recently developed framework for accelerometer monitoring in snakes, a group that has otherwise been completely overlooked in biologging applications. The proposed validation procedures are the essential first step toward translating these techniques to field applications, and, ultimately, improving analysis of the relationships between snake behavior and key internal and environmental variables

Preliminary Performance of the Advanced Dental Admission Test (ADAT): Association Between ADAT Scores and Other Variables for Applicants to Residency Programs at a U.S. Dental School

Historically, dental residency programs have used numerical assessment criteria to evaluate and identify qualified candidates for admission. Recent elimination of such assessment tools has undermined many programs’ holistic evaluation process. The Advanced Dental Admission Test (ADAT) was developed and recently piloted in hopes of addressing this issue. The aim of this study was to evaluate the preliminary performance and validity of the ADAT by exploring the association between ADAT scores and other variables for a sample of applicants to residency programs. The WebAdMIT admissions database was used to identify the test scores and educational and demographic information of 92 individuals who completed the pilot ADAT and were seeking a 2017 postgraduate specialty position at Indiana University School of Dentistry. The results showed that the ADAT had strong to weak correlations with certain applicant variables (p<0.05). No significant differences were found for age, race, school location, or country of origin. However, males performed better than females (p<0.05), and non-Hispanics performed better than Hispanics (p<0.01). ADAT component scores were also higher for individuals with a history of research activity (p<0.05). This study found that significant associations existed between the ADAT and indices typically associated with competitive applicants. These findings suggest that the ADAT may serve as a useful numerical assessment instrument, with the potential to identify high-performing candidates. Furthermore, the ADAT seemed to be a plausible option for programs seeking to incorporate a quantitative assessment instrument as part of a holistic candidate selection process

Revisiting the energetics hypothesis: can accelerometer monitoring reveal hidden variation in the movement patterns of snakes?

Historically, predators have been classified into two categories based upon how they search for and acquire prey. Active foragers move through the environment in search of prey, while ambush foragers “sit-and-wait” in selected positions for prey to pass. This difference in energetic demands is expected to correlate with disparities in the time species allocate to various behaviors. According to this energetics hypothesis, ambush foragers should exhibit reduced movement and space use relative to co-occurring active foragers. Snakes represent traditionally overlooked model organisms for exploring these associations, particularly the interplay between movement, foraging mode, and thermal preferences. Radio telemetry is the primary tool for measuring snake movement, however, coarse measures of activity hinder examination of movement patterns at finer temporal scales. This study capitalizes on recently validated procedures integrating radio telemetry and accelerometry for continuous monitoring of the spatial and temporal dimensions of movement behavior in snakes. We will carry out an improved test of the energetics hypothesis by exploring these associations in ambush-foraging Timber Rattlesnakes (Crotalus horridus) and active-foraging Rat Snakes (Pantherophis alleghaniensis). This project will provide a blue-print for future hypothesis-driven studies on movement behavior in small and secretive species using emerging animal-borne datalogging technologies

The Effects of Roadways on the Spatial and Temporal Movement Patterns of Timber Rattlesnakes (Crotalus horridus)

Roadways are among the most widespread and disruptive anthropogenic land use features that influence the behavior and movement of wildlife. Negative impacts include vehicle-induced mortality, habitat destruction and fragmentation, and creating barriers to movement which can have far-reaching sub-lethal effects. In an effort to improve upon historical methods of evaluating the influence of prominent landscape features, such as roads, on the movement of small and secretive wildlife, we are using a novel integration of emerging spatial analyses and tri-axial accelerometry in Timber Rattlesnakes (Crotalus horridus) from central Georgia. We used dynamic Brownian Bridge Movement Models to estimate motion variance and utilization distributions (UDs) for individual rattlesnakes, and accelerometers simultaneously provide long-term and continuous activity budgets to quantify “real-time” temporal movement patterns. Relating these spatial and temporal metrics to the Mean Distance to Roadway (MDR) revealed no significant associations when considering the full sample. However, sub-setting the data by sex revealed a significant positive linear relationship in males between MDR and Distance Per Movement (DPM) and UDs. These preliminary results indicate that with decreasing distance to roads, males use less space and move shorter distances per movement (DPM), suggesting that roads might pose as a passive barrier to movement for males in our population. Interestingly, we also detected a significant negative linear relationship between MDR and mean Hours spent Moving per Day (HMD) by male rattlesnakes. Given that this opposing relationship between MDR and the spatial and temporal patterns of movement was not displayed by females, we suspect that males in close proximity to roads might be compensating for smaller home range sizes (and reduced overlap with females) by increasing activity (HMD) during the mating season (August-October) to elevate encounter frequencies with reproductive females. Increasing our sample size and duration of monitoring will help to refine these preliminary findings

PyNAST: a flexible tool for aligning sequences to a template alignment

Motivation: The Nearest Alignment Space Termination (NAST) tool is commonly used in sequence-based microbial ecology community analysis, but due to the limited portability of the original implementation, it has not been as widely adopted as possible. Python Nearest Alignment Space Termination (PyNAST) is a complete reimplementation of NAST, which includes three convenient interfaces: a Mac OS X GUI, a command-line interface and a simple application programming interface (API)

High-frequency accelerometer recording of key predatory behaviors in vipers: validation and case study with Timber Rattlesnakes (Crotalus horridus)

High-frequency accelerometer recording of key predatory behaviors in vipers: validation and case study with Timber Rattlesnakes (Crotalus horridus) Morgan Thompson, Richard H. Adams, Anna F. Tipton, and Dominic L. DeSantis Tri-axial accelerometers (ACTs) are becoming increasingly common in studies of animal behavior wherein direct observation of subjects in nature is constrained or impossible. ACTs are small (\u3c 1 g) piezo-electric (spring-like) sensors that measure three-dimensional acceleration (upward, downward, and side-to-side) derived from subject motion. When leveraged with advanced machine learning techniques, these data can enable precise automated classification of a wide range of movement-mediated behaviors. Until recently, ACTs were largely reserved for larger-bodied organisms or those most amenable to the temporary external attachment of devices. Ongoing ACT miniaturization has now expanded the breadth of organisms amenable to these methods. This project aims to expand on a recently developed framework for ACT monitoring in wild-ranging snakes, a group that has been mostly overlooked in biologging applications. We are currently conducting extensive captive validation trials for robust model training and testing to enable classification of predatory behaviors, including striking and ingestion of prey items, in Timber Rattlesnakes (Crotalus horridus). Following captive validation, we will translate this method to the field with a population of C. horridus in the lower Piedmont of middle Georgia to evaluate the efficacy of externally attached ACTs for remote and continuous monitoring of predatory behaviors by wild-ranging vipers. We envision validation of this technique carrying significant conservation and management implications; real-time monitoring of foraging efficiency in the field opens the door to improved interpretation of the causes and consequences of variation in individual behavior and performance, and its ultimate effects on population trajectories

Precursor processes of human self-initiated action

A gradual buildup of electrical potential over motor areas precedes self-initiated movements. Recently, such "readiness potentials" (RPs) were attributed to stochastic fluctuations in neural activity. We developed a new experimental paradigm that operationalised self-initiated actions as endogenous 'skip' responses while waiting for target stimuli in a perceptual decision task. We compared these to a block of trials where participants could not choose when to skip, but were instead instructed to skip. Frequency and timing of motor action were therefore balanced across blocks, so that conditions differed only in how the timing of skip decisions was generated. We reasoned that across-trial variability of EEG could carry as much information about the source of skip decisions as the mean RP. EEG variability decreased more markedly prior to self-initiated compared to externally-triggered skip actions. This convergence suggests a consistent preparatory process prior to self-initiated action. A leaky stochastic accumulator model could reproduce this convergence given the additional assumption of a systematic decrease in input noise prior to self-initiated actions. Our results may provide a novel neurophysiological perspective on the topical debate regarding whether self-initiated actions arise from a deterministic neurocognitive process, or from neural stochasticity. We suggest that the key precursor of self-initiated action may manifest as a reduction in neural noise

Metabolic and Subjective Results Review of the Integrated Suit Test Series

Crewmembers will perform a variety of exploration and construction activities on the lunar surface. These activities will be performed while inside an extravehicular activity (EVA) spacesuit. In most cases, human performance is compromised while inside an EVA suit as compared to a crewmember s unsuited performance baseline. Subjects completed different EVA type tasks, ranging from ambulation to geology and construction activities, in different lunar analog environments including overhead suspension, underwater and 1-g lunar-like terrain, in both suited and unsuited conditions. In the suited condition, the Mark III (MKIII) EVA technology demonstrator suit was used and suit pressure and suit weight were parameters tested. In the unsuited conditions, weight, mass, center of gravity (CG), terrain type and navigation were the parameters. To the extent possible, one parameter was varied while all others were held constant. Tests were not fully crossed, but rather one parameter was varied while all others were left in the most nominal setting. Oxygen consumption (VO2), modified Cooper-Harper (CH) ratings of operator compensation and ratings of perceived exertion (RPE) were measured for each trial. For each variable, a lower value correlates to more efficient task performance. Due to a low sample size, statistical significance was not attainable. Initial findings indicate that suit weight, CG and the operational environment can have a large impact on human performance during EVA. Systematic, prospective testing series such as those performed to date will enable a better understanding of the crucial interactions of the human and the EVA suit system and their environment. However, work remains to be done to confirm these findings. These data have been collected using only unsuited subjects and one EVA suit prototype that is known to fit poorly on a large demographic of the astronaut population. Key findings need to be retested using an EVA suit prototype better suited to a larger anthropometric portion of the astronaut population, and elements tested only in the unsuited condition need to be evaluated with an EVA suit and appropriate analog environment

Modulation of morphology and glycan composition of mucins in farmed guinea fowl (Numida meleagris) intestine by the multi-strain probiotic slab51®

Probiotics have become highly recognized as supplements for poultry.Since gut health can be considered synonymous withanimal health, the effects of probiotic Slab51® on the morphology and the glycan composition of guineafowlintestine were examined. The probiotics were added in drinking water (2 × 1011 UFC/L) throughout the grow-out cycle.Birds were individually weighed andslaughtered after four months. Samples from the duodenum, ileum and caecum were collected and processed for morphological, morphometric, conventional and lectin glycohisto-chemical studies.The results were analyzed for statistical significance by Student’s t test. Compared with control samples, probiotic group revealed (1) significant increase in villus height (p &lt; 0.001 in duodenum and ileum; p &lt; 0.05 in caecum), crypt depth (p &lt; 0.001 in duodenum and caecum;p &lt; 0.05 in ileum) and goblet cells (GCs) per villus (p &lt; 0.001) in all investigated tracts; (2) increase in galac-toseβl,3N-acetylgalacyosamine(Galβl,3GalNAc)terminating O-glycans and αl,2-fucosylated glycans secretory GCs in the duodenum; (3) increase in α2,6-sialoglycans and high-mannose N-linked glycans secretory GCs but reduction in GCs-secreting sulfoglycans in the ileum; (4) increase in Galβl,3GalNAc and high-mannose N-linked glycans secretory GCs and decrease in GCs-producing sulfomucins in the caecum; (5) increase in the numbers of crypt cells containing sulfate and non-sulfated acidic glycans. Overall, dietary Slab51® induces morphological and region-specific changes in glycoprotein composition of guinea fowl intestine, promoting gut health

Age-related changes in the primary motor cortex of newborn to adult domestic pig sus scrofa domesticus

The pig has been increasingly used as a suitable animal model in translational neuroscience. However, several features of the fast-growing, immediately motor-competent cerebral cortex of this species have been adequately described. This study analyzes the cytoarchitecture of the primary motor cortex (M1) of newborn, young and adult pigs (Sus scrofa domesticus). Moreover, we investigated the distribution of the neural cells expressing the calcium-binding proteins (CaBPs) (calretinin, CR; parvalbumin, PV) throughout M1. The primary motor cortex of newborn piglets was characterized by a dense neuronal arrangement that made the discrimination of the cell layers difficult, except for layer one. The absence of a clearly recognizable layer four, typical of the agranular cortex, was noted in young and adult pigs. The morphometric and immunohistochemical analy-ses revealed age-associated changes characterized by (1) thickness increase and neuronal density (number of cells/mm2 of M1) reduction during the first year of life; (2) morphological changes of CR-immunoreactive neurons in the first months of life; (3) higher density of CR-and PV-immunopositive neurons in newborns when compared to young and adult pigs. Since most of the present findings match with those of the human M1, this study strengthens the growing evidence that the brain of the pig can be used as a potentially valuable translational animal model during growth and development