61871 research outputs found
Sort by
Escorting of a mother humpback whale ( Megaptera novaeangliae ) and the death of her calf during aggressive mating behavior
No full textThe humpback whale (Megatera novaengliae) is a cosmopolitan species of large whale that typically undertakes annual migrations between high latitude summer feeding areas and low latitude winter breeding and calving areas (Dawbin, 1966)..
Sequencing of the viral UL111a gene directly from clinical specimens reveals variants of HCMV-encoded IL-10 that are associated with altered immune responses to HCMV
Get PDFHuman cytomegalovirus (HCMV) is a beta-herpesvirus carried by ~80% of adults worldwide. Acute infections are often asymptomatic in healthy individuals but generate diverse syndromes in neonates, renal transplant recipients (RTR), and people with HIV (PWH). The HCMV gene UL111a encodes a homolog of human interleukin-10 (IL-10) that interacts with the human IL-10 receptor. Deep sequencing technologies were used to sequence UL111a directly from 59 clinical samples from Indonesian PWH and Australian RTR, healthy adults, and neonates. Overall, 93% of samples contained more than one variant of HCMV, as defined by at least one nonsynonymous variation. Carriage of these variants differed between neonates and adults, Australians and Indonesians, and between saliva and blood leukocytes. The variant alleles of N41D and S71Y occurred together in Australian RTR and were associated with higher T-cell responses to HCMV pp65. The variant P122S was associated with lower levels of antibodies reactive with a lysate of HCMV-infected fibroblasts. L174F was associated with increased levels of antibodies reactive with HCMV lysate, immediate-early 1 (IE-1), and glycoprotein B (gB) in Australian RTR and Indonesians PWH, suggesting a higher viral burden. We conclude that variants of UL111a are common in all populations and may influence systemic responses to HCMV
Single stranded fully Modified-Phosphorothioate oligonucleotides can induce structured nuclear inclusions, alter nuclear protein localization and disturb the transcriptome In Vitro
Get PDFOligonucleotides and nucleic acid analogues that alter gene expression are now showing therapeutic promise in human disease. Whilst the modification of synthetic nucleic acids to protect against nuclease degradation and to influence drug function is common practice, such modifications may also confer unexpected physicochemical and biological properties. Gapmer mixed-modified and DNA oligonucleotides on a phosphorothioate backbone can bind non-specifically to intracellular proteins to form a variety of toxic inclusions, driven by the phosphorothioate linkages, but also influenced by the oligonucleotide sequence. Recently, the non-antisense or other off-target effects of 2′ O- fully modified phosphorothioate linkage oligonucleotides are becoming better understood. Here, we report chemistry-specific effects of oligonucleotides composed of modified or unmodified bases, with phosphorothioate linkages, on subnuclear organelles and show altered distribution of nuclear proteins, the appearance of highly stable and strikingly structured nuclear inclusions, and disturbed RNA processing in primary human fibroblasts and other cultured cells. Phosphodiester, phosphorodiamidate morpholino oligomers, and annealed complimentary phosphorothioate oligomer duplexes elicited no such consequences. Disruption of subnuclear structures and proteins elicit severe phenotypic disturbances, revealed by transcriptomic analysis of transfected fibroblasts exhibiting such disruption. Our data add to the growing body of evidence of off-target effects of some phosphorothioate nucleic acid drugs in primary cells and suggest alternative approaches to mitigate these effects
Technology-enhanced learning and teaching: Narratives of secondary English teachers in Western Australia
Get PDFThis qualitative study explored teacher beliefs, decision-making, and pedagogical practices for using digital technologies in Western Australian secondary English classrooms. Driven by technology and the assumption that technology integration enhances student learning, the secondary school education landscape is undergoing a period of rapid change. While some stakeholders view teachers’ pedagogical practice as integrated with technology-enhanced learning (TEL), the literature identifies that the contrary is often true: technology use and deployment can be uneven and unsystematic. This study aimed to understand these perceptions via three research questions, that explored TEL's effects on secondary English teaching, both before and after the COVID-19 pandemic home learning experience. Six secondary English teachers were recruited via professional networking. Employing a narrative inquiry methodology, semi-structured interview questions were designed to encourage participants to share their pedagogical approaches and experiences with technology. The interview data were analysed using narrative thematic analysis and dominant themes were identified. The analysis found that teacher participants articulated stories of change and adaptation when using TEL, which gave insight into both personal and professional beliefs regarding education technology. Additional findings report that the home-learning experience during the pandemic has opened up possibilities for new digital pedagogies. However, this was counterbalanced by reinforcement of traditional beliefs about behaviour management, student learning, and teacher agency. The study concludes that if the knowledge gained from home learning in 2020 is utilised in positive ways to further integrate digital pedagogies into curricula, all educational stakeholders are likely to benefit. Furthermore, findings may have implications for twenty-first century in-service and pre-service teacher education to ensure that TEL functions as an enhancement to learning in its broadest sociocultural context
Hands-On Bayesian Neural Networks—A Tutorial for Deep Learning Users
No full textModern deep learning methods constitute incredibly powerful tools to tackle a myriad of challenging problems. However, since deep learning methods operate as black boxes, the uncertainty associated with their predictions is often challenging to quantify. Bayesian statistics offer a formalism to understand and quantify the uncertainty associated with deep neural network predictions. This tutorial provides deep learning practitioners with an overview of the relevant literature and a complete toolset to design, implement, train, use and evaluate Bayesian neural networks, i . e ., stochastic artificial neural networks trained using Bayesian methods
Simazine degradation in agroecosystems: Will it be affected by the type and amount of microplastic pollution?
No full textPlastics and herbicides represent two of the most extensive and persistent anthropogenic contaminants entering agroecosystems. The synergistic interaction of these pollutants on soil health, however, remains poorly understood. For the first time, we investigated the behavior of a common selective triazine herbicide (simazine) in soil containing 0%, 1%, 5%, 10%, and 20% (w/w) of two commonly found microplastics, namely polyethylene (PE) and polyvinyl chloride (PVC). The mineralization of 14C-labeled simazine in soil decreased with the presence of both PE and PVC as indicated by the lower total 14CO2 loss. Consequently, the half-life of simazine increased in the presence of microplastics, although there was little difference between microplastic types. The ratio of fungi-to-bacteria in the soil increased by 9%–18% after 1% of microplastics addition, while enzyme activities involved in C-cycling decreased by 20%–46% in soil amended with PVC relative to the control. Further, enzyme activities were negatively correlated with the half-life of simazine when added with PVC. Therefore, we ascribe the repression in simazine degradation to changes in microbial community structure (increased fungi-to-bacteria ratio) and reduced enzyme activities. Overall, microplastics accumulation in soil decreases herbicide breakdown resulting in herbicide residuals remaining, which in turn, may increase their risk of reaching ground or surface waters
Conservation agriculture practice influences soil organic carbon pools in intensive rice‐based systems of the Eastern Indo‐Gangetic Plain
No full textStudies of rice-based systems in the Indo-Gangetic Plain (IGP) have demonstrated the beneficial effects of Conservation Agriculture on soil organic carbon (SOC) status, along with increased soil health and crop productivity. However, it remains unclear as to the time for such treatments to have a positive effect. In this study of lentil-mung bean-rice and wheat-mung-rice rotations in Bangladesh positive effects of strip planting or bed planting, along with residue return, on SOC pools were apparent after 1.5 years, compared with intensive conventional tillage and limited residue return. Conventional tillage resulted in higher CO2 emission compared with strip planting or bed planting as did high residue return. In the cereal-dominated rotation, the strip planting system sequestered carbon at a rate of 0.24–0.53 Mg C ha−1 year−1 (at 0–0.15 m depth) while conventional tillage was associated with a carbon loss of 0.52–0.82 Mg C ha−1 year−1. In the legume-dominated rotation, neither practice sequestered SOC. Under strip planting, a minimum annual crop residue input of 1.7 Mg C ha−1 for the cereal-dominated system and 5.2 Mg C ha−1 for the legume-dominated system was required to maintain SOC at equilibrium. We conclude that strip planting with high levels of crop residue return can be an effective and quick strategy in either slowing the loss of SOC or improving C sequestration in the intensive rice-based systems of the Eastern IGP
Ozone Treatment Increases the Release of VOC from Barley, Which Modifies Seed Germination
No full textOzone is widely used to control pests in grain and has an impact on seed germination. The germination process involves multiple secondary metabolites, such as volatile organic compounds (VOCs), which are altered under ozone treatment. Here, an optimized solid-phase microextraction coupled with gas chromatography–mass spectrometry was implemented to explore changes in VOCs from barley seeds under ozone treatment. The data demonstrated that barley released both a greater variety and quantity of VOCs under oxidative stress. The number of alcohols and hydrocarbons gradually decreased, whereas aldehydes and organic acids markedly increased with increasing ozone treatment time. Acetic acid was identified as a potential ozone stress-specific marker. Furthermore, the dosage-dependent function of acetic acid on the germination of barley was verified, namely, a low dosage of acetic acid increased the germination and vice versa. This study provided new insights into how barley responds to ozone treatment and highlighted the role of acetic acid in seed germination
Genome-wide study of DNA methylation shows alterations in metabolic, inflammatory, and cholesterol pathways in ALS
No full textAmyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with an estimated heritability between 40 and 50%. DNA methylation patterns can serve as proxies of (past) exposures and disease progression, as well as providing a potential mechanism that mediates genetic or environmental risk. Here, we present a blood-based epigenome-wide association study meta-analysis in 9706 samples passing stringent quality control (6763 patients, 2943 controls). We identified a total of 45 differentially methylated positions (DMPs) annotated to 42 genes, which are enriched for pathways and traits related to metabolism, cholesterol biosynthesis, and immunity. We then tested 39 DNA methylation–based proxies of putative ALS risk factors and found that high-density lipoprotein cholesterol, body mass index, white blood cell proportions, and alcohol intake were independently associated with ALS. Integration of these results with our latest genome-wide association study showed that cholesterol biosynthesis was potentially causally related to ALS. Last, DNA methylation at several DMPs and blood cell proportion estimates derived from DNA methylation data were associated with survival rate in patients, suggesting that they might represent indicators of underlying disease processes potentially amenable to therapeutic interventions
Antimicrobial use on Australian dairy cattle farms – A survey of veterinarians
No full textAims
The aims of this study were to determine antimicrobial prescription patterns and the factors affecting antimicrobial selection amongst Australian dairy veterinarians.
Methods
A structured questionnaire was administered to Australian dairy cattle veterinarians using the Qualtrics online survey platform. Questions focused on their (1) demographics; (2) opinions surrounding antimicrobial use, resistance, and stewardship; (3) decision-making drivers of both prescription and selection of commonly prescribed antimicrobials; (4) awareness on the guidelines for antimicrobial usage and sources of information concerning antimicrobials.
Key results
A total of 135 responses (14.1% response rate) from all eight dairying regions in Australia were received. The attitudes, perceptions, and concerns of dairy veterinarians towards antimicrobials indicated a high agreement regarding label indications (96%), consequences of off-label prescription (95%), and the presence of an antimicrobial resistance (AMR) risk (73%), when prescribing antibiotics. A four-dimensional categorical principal components analysis (CATPCA) model indicated most of the variation in opinion was due to AMR risk, trade-offs, prescription concerns and active substance concerns. The first active substance most dairy veterinarians chose for a scenario involving mastitis and dry cow therapy (DCT) treatment was cloxacillin. Decision-making drivers for antimicrobial choice when providing advice regarding the supply of antimicrobials for mastitis and DCT treatment were predominately clinical factors; however, diagnostics were rarely used in determining antimicrobial choice due to cost of implementation, diagnostic accuracy (sensitivity, specificity), and benefit issues. Non-clinical decision-making drivers included the perception of practicality for Australian Veterinary Association (AVA) prescription guidelines, opinions surrounding AMR risk and prescription concerns, consideration of Expert Advisory Group on Antimicrobial Resistance (EAGAR) scores, number of years worked with dairy farms, and the number of dairy farms they regularly consult for. When available at the practice, prescription policies were considered to impact on animal welfare outcomes and on the probability of AMR emergence. The major information sources influencing decision making on antimicrobial prescription for the Australian dairy veterinarians were clinical experience (93%) and product labels (81%).
Conclusions
Australian dairy veterinarians are generally aware of the risk of resistance to antimicrobials and the need for stewardship, with clinical factors having the most impact on antimicrobial prescription. However, non-clinical factors incorporating awareness of guidelines and their attitudes on antimicrobial resistance risk and prescription concerns impact on the choice and prescription of antimicrobials.
Implications
The development of prescription policy and guidelines, alongside effective communicative extension programs to increase veterinarian uptake, provides an avenue to mitigate AMR risk in Australian dairy cattle