Demand evidence and think critically: building research excellence in tomorrow's scientists

Biomedical science students represent an essential resource for the future scientific workforce. As research scientists are more than their content specialities they must embody core values that govern the development and certification of knowledge. However, the ethos of science is often overlooked in University education in favour of increasing levels of content delivery. This results in graduates with rich content knowledge but limited ability in the generic skills and ethos of a research scientist. To address these concerns, authentic scientific research and communication experiences based on an apprenticeship model were developed to provide realistic insight into scientific ethos and to foster critical thinking, analytical and communication skills. By adapting transitional pedagogy commonly associated with First Year Experience and the Research Skills Development framework, our research-led teaching initiatives allowed students who were considering a career in science true insight into what such a career entails. Students take on the role of ‘scientists in training’, stepping out of their academic comfort zone within a safe environment where ‘perfect’ data are no longer generated and adapting to setbacks forms part of the learning process. Success is reflected by positive feedback from students and peers, increased assessment performance, and graduates continuing in science careers

Smoking, particulate fuel use, increasing BMI (but not betel use) increase the probability of obstructive airway conditions in adults fron National Capital District, PNG

Exposure to tobacco smoke and particulates from biomass fuel smoke are a risk factors for Chronic Obstructive Pulmonary Disease (COPD). Papua New Guinea has a high prevalence of smoking, which is a leading cause of COPD. In addition to tobacco use, many families in PNG also use fuels producing particulate smoke for cooking (e.g. wood, charcoal or kerosene) which may further increase the risk of developing lung disease. The chewing of Betel nut (Areca catechu) is also prevalent in PNG, and has been shown to cause bronchoconstriction in asthmatic patients. This study was conducted to determine the relative contribution of smoking, particulate fuel use, and betel use have on the probability of developing obstructive lung disease. A prospective cross-sectional study measured the lung function of apparently healthy adults residing in the National Capital District. Lung function was assessed using spirometry, which was conducted according to the American Thoracic Society guidelines. Seventy-six subjects met the inclusion criteria out of hundred and forty volunteers. Smoking and biomass smoke inhalation both independently increased the probability of decreased lung function as measured by a %FEV1/FVC less than 80% of the predicted value. The use of betel was not found to significantly alter the probability of lowering %FEV1/FVC below 80% of predicted values. Interesting, increasing BMI was found to increase the probability of decreasing lung function in smokers who did not use particulate fuels and in particulate fuel users who did not smoke, and was most significant in smokers who used particulate fuels. Understanding the interactive effects between COPD risk factors will help predict health outcomes in PNG and increase public education on COPD prevention

Calibration of the HemoCue point-of-care analyser for determining haemoglobin concentration in a lizard and a fish

Haemoglobin concentration ([Hb]) is measured for a wide variety of animal studies. The use of point-of-care devices, such as the HemoCue, is becoming increasingly common because of their portability, relative ease of use and low cost. In this study, we aimed to determine whether the [Hb] of blue-tongued skink (Tiliqua nigrolutea) blood can be determined accurately using the HemoCue and whether the HemoCue overestimates the [Hb] of reptile blood in a similar manner to fish blood. Additionally, we aimed to test whether ploidy affected [Hb] determined by the HemoCue using blood from diploid and triploid Atlantic salmon (Salmo salar). The HemoCue Hb 201⁺ systematically overestimated [Hb] in both blue-tongued skinks and Atlantic salmon, and there was no difference between calibration equations determined for diploid or triploid salmon. The overestimation was systematic in both species and, as such, [Hb] determined by the HemoCue can be corrected using appropriate calibration equations

The importance of the crocodilian hepatic piston pump to ventilation during altered respiratory demand

Crocodilians ventilate through a combination of the intercostal muscles, the abdominal muscles and the diaphragmaticus muscle. Previous studies report that the caudal-cranial movement of the liver during the ventilatory cycle by the diaphragmaticus muscle, termed the hepatic piston pump, is solely responsible for ventilation in floating caimans. However, the importance of the hepatic-piston pump to ventilation in crocodilians under altered conditions of ventilatory demand is unknown. The hepatic-piston pump made only a limited contribution to ventilation while crocodiles rested at 30OC, following a decrease in temperature (20OC, reduced ventilatory demand), and during hypercapnia (5% CO2, increased ventilatory drive). The diaphragmatic muscle was important for facilitating ventilation during exercise (increased ventilatory demand) as loss of the hepatic piston pump, following inactivation of the diaphragmaticus muscle, compromised exercise induced increases in tidal volume and minute ventilation. A relative hyperventilation was induced by exercise (both with and without a functional hepatic piston pump) and, as a result, the alterations in ventilation following inactivation of the diaphragmaticus muscle did not significantly alter arterial oxygenation

Demand evidence and think critically: Building research excellence in tomorrow’s scientists

Biomedical science students represent an essential resource for the future scientific workforce. As research scientists are more than their content specialities they must embody core values that govern the development and certification of knowledge. However, the ethos of science is often overlooked in University education in favour of increasing levels of content delivery. This results in graduates with rich content knowledge but limited ability in the generic skills and ethos of a research scientist. To address these concerns, authentic scientific research and communication experiences based on an apprenticeship model were developed to provide realistic insight into scientific ethos and to foster critical thinking, analytical and communication skills. By adapting transitional pedagogy commonly associated with First Year Experience and the Research Skills Development framework, our research-led teaching initiatives allow students who are considering a career in science true insight into what such a career entails. Students take on the role of ‘scientists in training’, stepping out of their academic comfort zone within a safe environment where ‘perfect’ data are no longer generated and adapting to setbacks forms part of the learning process. Success is reflected by positive feedback from students and peers, increased assessment performance, and graduates continuing in science careers

Geographical variation in the standard physiology of brushtail possums (Trichosurus): implications for conservation translocations

Identifying spatial patterns in the variation of physiological traits that occur within and between species is a fundamental goal of comparative physiology. There has been a focus on identifying and explaining this variation at broad taxonomic scales, but more recently attention has shifted to examining patterns of intra-specific physiological variation. Here we examine geographic variation in the physiology of brushtail possums (Trichosurus), widely distributed Australian marsupials, and discuss how pertinent intra-specific variation may be to conservation physiology. We found significant geographical patterns in metabolism, body temperature, evaporative water loss and relative water economy. These patterns suggest that possums from warmer, drier habitats have more frugal energy and water use and increased capacity for heat loss at high ambient temperatures. Our results are consistent with environmental correlates for broad-scale macro-physiological studies, and most intra-generic and intra-specific studies of marsupials and other mammals. Most translocations of brushtail possums occur into Australia\u27s arid zone, where the distribution and abundance of possums and other native mammals have declined since European settlement, leading to reintroduction programmes aiming to re-establish functional mammal communities. We suggest that the sub-species T. vulpecula hypoleucus from Western Australia would be the most physiologically appropriate for translocation to these arid habitats, having physiological traits most favourable for the extreme Ta, low and variable water availability and low productivity that characterize arid environments. Our findings demonstrate that geographically widespread populations can differ physiologically, and as a consequence some populations are more suitable for translocation to particular habitats than others. Consideration of these differences will likely improve the success and welfare outcomes of translocation, reintroduction and management programmes

Computational fluid dynamics modelling of pumonary airflow in varanid lizards

Understanding the biomechanical basis of undirectional pulmonary airflow, a condition where lung gases travel in the one direction through most of the airways and throughout the respiratory cycle, has long been of interest to scientists. Recent work has revealed a wide phylogenic distribution of this trait, beyond the confines of Aves, to include crocodilians, green goannas and monitor lizards. Advances in computational fluid dynamics, a technique where patterns of flow are simulated from prescribed boundary conditions by laws of fluid motions, provide a powerful tool to study airflow through these complex and fascinating structures. Australian monitor lizards (varanidae) are a promising group to investigate the significance of these lung traits because their adaptive radiation crosses many ecological [unreadable] with a similar body plan. Computed tomography scans of varanid species being made and segmented into a detailed computational meshes, representing the major and minor airways as has already been done for the savannah monitor, Varanus exanthematicus. Flow patterns are simulated through these airways in two ways on a high performance computing cluster using dynamic and static OpenFOAM solvers and visualized using ParaView

A Standardized Protocol for Measuring Bioelectrical Impedance in Green Turtles (Chelonia mydas)

Bioelectrical impedance analysis (BIA) is gaining popularity in wildlife studies as a portable technology for immediate and nondestructive predictions of body composition components, such as fat-free and fat masses. Successful application of BIA for field-based research requires the identification and control of potential sources of error, as well as the creation of and adherence to a standardized protocol for measurement. The aim of our study was to determine sources of error and to provide a standardization protocol to improve measurement precision of BIA on juvenile green turtles (Chelonia mydas; n=35 ). We assessed the effects of altered environmental temperature (20°C–30°C), postprandial state (2–72 h), and time out of the water (2 h) on five impedance parameters (resistance at infinite frequency [Rinf], resistance at zero frequency [R0], resistance at 50 kHz [R50], phase angle at 50 kHz [PhA50], and intracellular resistance [Ri]) using a bioimpedance spectroscopy device. Technical reproducibility of measurements and interanimal variability were also assessed. We found an inverse exponential relationship between change in environmental temperature and impedance parameters Rinf, R0, and R50. Postprandial state significantly increased Rinf and Ri 72 h after feeding. BIA measurements were reproducible within individual juvenile green turtles at temperatures from 20°C to 30°C. Significant variation in impedance values was found between animals at all temperatures, sampling times, and postprandial states, but the relative differences (%) were small in magnitude. Our study suggests that measurement precision is improved by measuring animals at consistent environmental temperatures close to their preferred thermal range. We propose a standardized protocol of measurement conditions to facilitate laboratory and field use of BIA for body composition assessment studies in turtles

Importance of health assessments for conservation in noncaptive wildlife

Wildlife health assessments help identify populations at risk of starvation, disease, and decline from anthropogenic impacts on natural habitats. We conducted an overview of available health assessment studies in noncaptive vertebrates and devised a framework to strategically integrate health assessments in population monitoring. Using a systematic approach, we performed a thorough assessment of studies examining multiple health parameters of noncaptive vertebrate species from 1982 to 2020 (n = 261 studies). We quantified trends in study design and diagnostic methods across taxa with generalized linear models, bibliometric analyses, and visual representations of study location versus biodiversity hotspots. Only 35% of studies involved international or cross‐border collaboration. Countries with both high and threatened biodiversity were greatly underrepresented. Species that were not listed as threatened on the International Union for Conservation of Nature Red List represented 49% of assessed species, a trend likely associated with the regional focus of most studies. We strongly suggest following wildlife health assessment protocols when planning a study and using statistically adequate sample sizes for studies establishing reference ranges. Across all taxa blood analysis (89%), body composition assessments (81%), physical examination (72%), and fecal analyses (24% of studies) were the most common methods. A conceptual framework to improve design and standardize wildlife health assessments includes guidelines on the experimental design, data acquisition and analysis, and species conservation planning and management implications. Integrating a physiological and ecological understanding of species resilience toward threatening processes will enable informed decision making regarding the conservation of threatened species

Field‐based adipose tissue quantification in sea turtles using bioelectrical impedance spectroscopy validated with CT scans and deep learning

Loss of adipose tissue in vertebrate wildlife species is indicative of decreased nutritional and health status and is linked to environmental stress and diseases. Body condition indices (BCI) are commonly used in ecological studies to estimate adipose tissue mass across wildlife populations. However, these indices have poor predictive power, which poses the need for quantitative methods for improved population assessments. Here, we calibrate bioelectrical impedance spectroscopy (BIS) as an alternative approach for assessing the nutritional status of vertebrate wildlife in ecological studies. BIS is a portable technology that can estimate body composition from measurements of body impedance and is widely used in humans. BIS is a predictive technique that requires calibration using a reference body composition method. Using sea turtles as model organisms, we propose a calibration protocol using computed tomography (CT) scans, with the prediction equation being: adipose tissue mass (kg) = body mass − (−0.03 [intercept] − 0.29 * length2/resistance at 50 kHz + 1.07 * body mass − 0.11 * time after capture). CT imaging allows for the quantification of body fat. However, processing the images manually is prohibitive due to the extensive time requirement. Using a form of artificial intelligence (AI), we trained a computer model to identify and quantify nonadipose tissue from the CT images, and adipose tissue was determined by the difference in body mass. This process enabled estimating adipose tissue mass from bioelectrical impedance measurements. The predictive performance of the model was built on 2/3 samples and tested against 1/3 samples. Prediction of adipose tissue percentage had greater accuracy when including impedance parameters (mean bias = 0.11%–0.61%) as predictor variables, compared with using body mass alone (mean bias = 6.35%). Our standardized BIS protocol improves on conventional body composition assessment methods (e.g., BCI) by quantifying adipose tissue mass. The protocol can be applied to other species for the validation of BIS and to provide robust information on the nutritional and health status of wildlife, which, in turn, can be used to inform conservation decisions at the management level