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Epigenetic Mechanisms Associated with Livestock Adaptation to Heat Stress
No full textThe livestock sector, a crucial source of revenue and global food security, is facing serious challenges due to climate change driven by global warming. This leads to serious effects on animal health and productivity, making it difficult for the livestock industry to meet the global demand and sustain the livelihoods of farmers. The main factor affecting livestock's productivity is heat stress. However, animals develop various adaptive mechanisms to cope with the effects of heat stress. Cellular and molecular responses act as key defense mechanisms, enabling animals adapt to environmental changes. The recent advancements in molecular biology have opened up opportunities for extensive research on epigenetics, which has a key role in regulating gene expression in animals in response to environmental stimuli. Such studies have gained considerable attention regarding heat acclimation in animals due to the fact that epigenetic mechanisms have been recognized as key players in long-term adaptation to high temperatures in farm animals. This review summarizes the different mechanisms and methodologies used to assess heat stress-associated epigenetic changes, including DNA methylation, which is an extensively studied epigenetic regulatory mechanism in relation to gene expression. The review also highlights the mechanisms and regulation of adaptation to heat stress in animals and collates information related to various epigenetic markers to assess the heat stress response, thereby aiding in improving thermal resilience in animals
Risk factors for smothering in three commercial free-range layer poultry farms, Australia 2019–2022
No full textIn intensively managed poultry production systems the term 'smothering' refers to deaths from suffocation that occur as a consequence of piling behaviour where birds crowd together into densely packed groups. Smothering is a non-negligible source of loss in free-range layer hens, having both negative welfare and economic effects. Smothering events are rarely observed and are usually detected by the discovery of groups of dead hens. The aim of this study was to identify risk factors for smothering deaths in three commercial free-range layer poultry farms in Australia. This was a prospective cohort study of poultry flocks managed by three commercial free-range layer farms in eastern Australia. Flocks were enrolled into the study from 1 January 2019-29 March 2021 and were followed until the end of lay or until the end of the study on 31 March 2022, whichever occurred first. Throughout the follow-up period of the study, daily production and weather data, details of flock management and details of the place and time of smothering events were recorded. Time to event (survival) analyses were used to quantify the association between hypothesised risk factors and the number of days in lay at the time of smothering. Shed and bird level characteristics associated with time to event were quantified using a stratified Cox proportional hazards model which included a frailty term to account for birds clustered within sheds within farm. Across the three farms, for every 100 birds placed into a shed, there were 12 deaths over the duration of the production period. Of the 12 deaths per 100 birds, 2 were due to smothering. Our Cox proportional hazards regression analyses showed that the daily hazard of smothering was increased for birds housed in aviary sheds compared with flat-deck sheds (HR 4.0, 95 % CI 1.7-9.7). The daily hazard of smothering mortality was increased on warm, humid and rainy days, and in birds with low fear of humans and high fear of novel objects. Rainy days on which outdoor daily average humidity was greater than or equal to 70 % were associated with a 3.7 (95 % CI 3.5-3.9) fold increase in the daily hazard of indoor smothering deaths, compared with days when outdoor daily average humidity was less than 70 % and no rain. This study provides useful insight into the determinants of smothering in Australian free-range layer hens, in particular risk factors that do not change over time (e.g., shed type) and those that change daily (e.g., weather conditions). This information allows flock management strategies to be adapted accordingly
For Self, Community, and the Environment: An Ethnographic Study of the Rural Women’s Movement of Nagar Valley, Pakistan
No full text© 2025 Rashid Ali HaideriThe thesis is an ethnography of a rural women’s movement in Nagar Valley, Pakistan, exploring its emergence, modalities, and impact based on 10 months of fieldwork. I argue that local women activists have responded to social and ecological concerns and have sought to refashion themselves and their community, reconfiguring the traditional social order and renegotiating gender complementarity. In doing so, they are forwarding an ‘alternative to development’, conceptualised as ‘politics of care’, based on their deeply communal, religious, and environmental ethos
Fourier limit in fluid mechanics, and link to the turbulence
No full textMacroscopic fluids are considered continuous down to microscopic scales where they fail to be dense enough for separate particles to have sufficiently large number of collisions (interactions) over that scale. We argue that a similar limit applies to the characteristic fluid length scales in the Fourier space, defined by wavenumber k. At [Formula presented], the Fourier space cannot be regarded continuous, and at these scales the energy-density spectrum becomes discrete. We further note that in physical space, the particle centres cannot come closer to each other than their diameter, and within this volume the physical forces are of a completely different nature. Similarly, very different interactions can be expected if wave modes have wavenumbers closer than a threshold in the Fourier space. It is argued that the wavenumber space [Formula presented] can be considered as a Fourier volume of wave mode k. It is the hypothesis of this paper that this volume of the Fourier modes is filled with background seed turbulence, - like the volume of solid particles in the physical space is filled with the matter. The wave energy between modes in the discrete wave spectrum is not missing, it is the energy of background turbulence, like internal energy of molecules of the moving solid particle. This turbulence seed energy is about 0.1 % of the energy of neighbouring wave modes as argued in this paper, and it can grow subject to instabilities. The unidirectional flow can be treated as a half-wave with wavelength twice the size of the phenomenon where the mean velocity defines kinetic energy, part of which goes to the seed turbulence. The depth (cross-length) of this flow is not an independent property and is proportional to ratio of the length and velocity scales all squared. In case of surface present, this depth is perpendicular to the surface and defines the length scale of the boundary layer
Cardiac arrest events on Australian beaches
No full textBackground: Surf Life Saving Australia (SLSA) members respond to cardiac arrests near their patrolling location and have successfully resuscitated many community members over the years. In addition, members often act as first responders to cardiac arrest events in community settings, workplaces or through applications such as GoodSAM®. The outcomes achieved are not known after an update to resuscitation guidelines. Objective: We aimed to analyse Surf Life Saving Australia data on cardiopulmonary resuscitation (CPR) and describe the epidemiology and outcomes of cardiac arrest on Australian beaches and factors associated with survival after CPR. Methods: Using SLSA's national Incident Reporting Database held by Surf Life Saving Australia, anonymised incident report forms were analysed to determine the incidence, aetiology and outcomes of CPR events attended by SLSA members on Australian beaches. Results: Between December 2000 and May 2020 there were 158 incidents where CPR was provided SLSA members. Mean patient age was 46 years of age (SD 18.9), and 83 % were male. The majority (68 %) of patients were involved in water activities at the time of their requirement for CPR including swimming, wading, and watercraft activity. Return of spontaneous circulation (ROSC) was achieved before transport to hospital in 34 (22 %) of cases. An automated external defibrillator (AED) was applied on 42 patients, with seven being defibrillated. The two variables associated with higher odds of survival were the incident occurring in the flagged area (OR 4.0 [95 % CI: 1.5–11.2]) and the use of oxygen therapy (OR 2.8 [95 % CI: 1.1–7.1]). Conclusion: Cardiac arrest at the beach is an uncommon event. Cardiac arrest close to patrolling location and the use of oxygen were associated with improved odds of ROSC
Deep Phenotyping of the Broader Autism Phenotype in Epilepsy: A Transdiagnostic Marker of Epilepsy and Autism Spectrum Disorder
No full textABSTRACT
Objective
We conducted deep and minimal phenotyping of the broader autism phenotype (BAP) in people with epilepsy (PWE) and compared its expression with published rates in the general population and relatives of individuals with autism spectrum disorder (ASD‐relatives). We then examined the association of clinical epilepsy variables with BAP expression to explore its underpinnings in PWE.
Methods
103 adults with seizures (Mage = 37.37, SD = 12.50; 47% males; 51 temporal lobe epilepsy, 40 genetic generalized epilepsy, 12 other) and 58 community members (Mage = 39.59, SD = 14.56; 35% males) underwent deep phenotyping using the observer‐rated Autism Endophenotype Interview and minimal phenotyping with the Broader Autism Phenotype Questionnaire (BAPQ). Published rates of the BAP were ascertained from large randomly selected samples (n > 100) of the general population and ASD‐relatives based on BAPQ data.
Results
There was a higher rate of BAP in PWE (15% males, 27% females) compared with the general population (5% males, 7% females) and a similar rate to ASD‐relatives (9% males, 20% females). Deep phenotyping identified an additional 22 males and 10 females, with the combined measures indicating elevated rates of the BAP in PWE (44% males, 36% females). Only a shorter duration of epilepsy was weakly correlated with BAP trait expression in males (r = − 0.21, p = 0.05).
Interpretation
PWE have a high rate of BAP, largely unrelated to secondary clinical epilepsy effects. The BAP may provide a trans‐diagnostic marker of shared etiological mechanisms of epilepsy and ASD and partly account for psychosocial difficulties faced by PWE with childhood or adult onset of seizures
Development and validation of a learning analytics rubric for self-regulated learning
No full textAbstract
This study presents the development and validation of a Learning Analytics Rubric for Self-Regulated Learning (SRL) in higher education. The rubric aims to measure students’ SRL processes within learning management systems (LMS) in a scalable, consistent, and explainable manner. The research follows a design-based approach, mapping validated SRL scales to LMS data indicators, developing the rubric for a Canvas LMS, and validating it with postgraduate students. The study identifies challenges in measuring SRL, such as the dynamic nature of SRL and the limitations of translating traditional self-report methods to digital environments. By leveraging learning analytics, the study proposes a novel approach to measure SRL behaviors using LMS data. The validation process reveals that five of the seven indicators accurately reflect students’ SRL skills, with strong alignment between student self-assessments and system-generated scores for indicators related to reviewing content, integrating information from multiple sources, following study schedules, pacing learning, and reading assessment instructions. However, significant discrepancies were observed in indicators measuring completion of extra activities and early semester engagement with the LMS, highlighting the need for further refinement. The findings suggest that integrating learning analytics with rubrics can provide valuable insights into students’ learning processes, particularly measuring SRL, while supporting the development of effective educational interventions from a student-centered approach
Body size rather than reflectivity explains thermal constraints on colour variation in an aposematic jewel bug
No full textAbstract
Theory posits that warning signals should converge phenotypically to reinforce predator memory, yet many aposematic species show substantial variation in warning signals within and between populations. This could be explained by alternative selective pressures on phenotype beyond predation such as thermoregulation, but empirical tests are scarce and do not consider the full spectrum of sunlight. To examine whether trade-offs with thermoregulation could explain variation in warning colouration, we examined thermal properties of colour variants of the aposematic cotton harlequin bug (Tectocoris diophthalmus). This species shows striking variation in warning signals: it is sexually dichromatic, varies within sexes, and shows clinal variation in colour frequencies, with iridescent blue-green colouration prevalent in cooler climates and non-iridescent red–orange colouration prevalent in warmer climates. We quantified reflectivity between colour variants over the full solar spectrum and investigated the contribution of ultraviolet and visible (UV–visible, 300–700 nm) and near infrared (NIR, 700–1700 nm) light on heating. Differences in reflectivity of iridescent and non-iridescent colour patches were greater in NIR than UV–visible wavelengths but did not result in significant differences in heating. However, we found a tight link between body size and reflectivity, with smaller males having lower reflectivity and heating faster. Due to the strong correlation between body size and colouration, thermal constraints related to body size may help to explain the observed clinal variation in colour frequencies
What really influences teacher attrition, migration, and retention?
No full textAbstract
Past research on teacher shortages due to turnover has not adequately distinguished between teachers leaving the profession (attrition) and moving between schools (migration), hindering the identification of tailored retention strategies for schools and/or the profession. This study, part of a comprehensive project including a systematic review, meta-analysis, and empirical investigation, surveyed 930 current and former K-12 teachers in Victoria, Australia. It explored their reasons for quitting, migrating, or remaining in the profession. Thematic analysis revealed that career factors and school characteristics primarily drive migration, whereas personal life stages and role compatibility influence attrition. Factors supporting retention include personal choice, job compatibility, and positive relationships with students and colleagues. Migration often stems from a quest for professional advancement and dissatisfaction with school culture. Conversely, attrition is predominantly driven by job dissatisfaction and burnout. The findings suggest that while migration can yield positive outcomes for departing teachers, some teachers may feel compelled to stay due to factors like poor employability, fear of change, or personal obligations. Importantly, the study captured voluntary and involuntary career decisions, with the latter often overlooked previously. This research underscores the need for tailored strategies that acknowledge and address both voluntary and involuntary aspects of teacher turnover
Energy and Exergy Analysis of a Photovoltaic-Thermal Geothermal Heat Pump Coupled with Radiant Ceiling and Fresh Air System
No full textThis paper presents energy and exergy studies on a photovoltaic-thermal solar-assisted geothermal heat pump coupled with a radiant ceiling system. The system utilizes renewable solar and geothermal energy. It has an independent fresh air unit that provides clean air to the space. The computer model of the system was developed under the TRNSYST environment and validated with experimental results from open literature. Distribution of the energy consumption and exergy loss of the system were analyzed. It was found that the heat pump unit consumes the largest amount of energy while the transmission and distribution system has the highest exergy loss. Under optimized operating conditions, i.e., both demand side circulation flow and source side circulation flow are maintained at 65% of the design flow rate (design loop water temperature difference of 7.0 °C), the average exergy efficiency of the whole system was found to be 37.56%, which achieves an accumulative exergy loss reduction of 16.5% compared with 100% design flow rate condition during cooling season. The optimal bearing load ratio of the ground source heat pump vs. photovoltaic-thermal system in the heating season was found to be 67%