2,052 research outputs found
Infertility problems and mental health symptoms in a community-based sample: depressive symptoms among infertile men, but not women
Most researchers agree that menās and womenās experiences of infertility are
fundamentally different, and impacts upon the nature of psychological distress
encountered. However, design flaws, including non-random samples
unrepresentative of the general population, compromise many existing studies. Data
derived from a random general community sample provides prevalence of current
infertility, and permits examination of longitudinal associations between mental
health symptoms and infertility among 1,978 participants aged 28-32 years. In the
previous 12-months, infertility was experienced by 2.1% and 5.4% partnered men
and women. Infertility independently predicted depressive symptomatology in men,
and anxiety symptoms among women. Gender differences were sustained, even
controlling for prior depression and anxiety. Health professionals are encouraged
to proactively enquire about affective symptoms experienced by both women and
men with infertility problems
Understanding why farmers change their farming practices : the role of orienting principles in technology transfer
This report presents results from a qualitative study of sheep, beef and dairy farmers in the
Temuka, Geraldine area of the South Island, New Zealand. Farmers' accounts of their farming
practices, and how they decide to adopt, or not adopt, innovations are analysed to highlight the key
orienting principles that guide their decision making. Farmers in each type of production have different
orientations to innovation, in large part reflecting the nature of the industry in which they are located.
Sheep and beef farmers emphasise profitability and the need to control risk and to farm safely. Dairy
farmers emphasise increasing production, increasing efficiency and control by monitoring production.
The results are important for alerting researchers and educationalists to the farmers' point of view in the development of effective extension.Funding for this research was received from the Foundation for Research, Science and Technology.
The Lotteries Board supported the research by providing technical equipment. The former New
Zealand Institute for Social Research and Development initiated this project and it was continued by the
AERU in November, 1994
An updated review of the toxicology and ecotoxicology of sodium fluoroacetate (1080) in relation to its use as a pest control tool in New Zealand
Sodium fluoroacetate (1080) is a vertebrate pesticide, originally developed in the 1940s and principally
used for the control of unwanted introduced animals in New Zealand and Australia. Fluoroacetate is also a
toxic component of poisonous plants found in Australia, Africa, South America, and India. In relation to its use
as a pesticide, recent research has focused on further elucidation of its potential sub-lethal effects, on animal
welfare issues, on understanding and reducing its risk to non-target species, on its ecotoxicology, and fate in the
environment following use in baits. 1080 acts by interfering with cellular energy production through inhibition
of the tricarboxylic acid cycle and lethal doses can kill animal pests within 6ā48 h of eating baits. Exposure
to sub-lethal doses has been shown to have harmful effects on the heart and testes in animal studies, and strict
safety precautions are enforced to protect contractors and workers in the pest control industry. Considerable
care must be taken when using 1080 for the control of animal pests. Primary poisoning of non-target birds and
secondary poisoning of dogs must be minimised to ensure that benefits in terms of conservation outcomes and
pest and disease control significantly outweigh the risks associated with its use. Despite over 60 years of research
and practical experience, the use of 1080 is still embroiled in controversy, while research efforts continue to
improve its target specificity when it is used as a conservation tool or for Tb vector control
Quantitative Lipoproteomics in Clostridium difficile Reveals a Role for Lipoproteins in Sporulation
This is the final version of the article. Available from Elsevier via the DOI in this record.Bacterial lipoproteins are surface exposed, anchored to the membrane by S-diacylglyceryl modification of the N-terminal cysteine thiol. They play important roles in many essential cellular processes and in bacterial pathogenesis. For example, Clostridium difficile is a Gram-positive anaerobe that causes severe gastrointestinal disease; however, its lipoproteome remains poorly characterized. Here we describe the application of metabolic tagging with alkyne-tagged lipid analogs, in combination with quantitative proteomics, to profile protein lipidation across diverse C.Ā difficile strains and on inactivation of specific components of the lipoprotein biogenesis pathway. These studies provide the first comprehensive map of the C.Ā difficile lipoproteome, demonstrate the existence of two active lipoprotein signal peptidases, and provide insights into lipoprotein function, implicating the lipoproteome in transmission of this pathogen.T.C. was funded by an EPSRC grant to the Institute of Chemical Biology, Imperial College London. A.K.-S. was funded by a European Union Seventh Framework Program (EU MCN Grant agreement 237942)
Effect of CO2 Dilution on the Structure and Emissions from Turbulent, Non-premixed Methane-Air Jet Flames
This investigation gives a comparison of the variation of temperature and gas compositions in lifted, turbulent non-premixed methaneāair jet flames firing vertically into still air with different carbon dioxide diluent concentrations in the fuel jet. The carbon dioxide mole fraction ranged from 0 to 0.22 and was varied with a fixed jet velocity so that dilution-induced extinction was achieved. The effect of the changes due to this dilution on the post-flame emissions was investigated. Similarly, visual observation of the changes in the flame structure in mixture fraction space at different diluent mole fraction has been studied. An examination of the changes in the flame length, lift-off height, flame temperature, composition, and on the emission indices of the species in the post-flame region were made. They showed an increase in the flame's lift-off height, a decrease in the overall flame length, a reduction in the flame temperature and a reduction in the NOx concentration at various levels of dilution of carbon dioxide in the fuel
Engaging Undergraduates in Science Research: Not Just About Faculty Willingness.
Despite the many benefits of involving undergraduates in research and the growing number of undergraduate research programs, few scholars have investigated the factors that affect faculty members' decisions to involve undergraduates in their research projects. We investigated the individual factors and institutional contexts that predict faculty members' likelihood of engaging undergraduates in their research project(s). Using data from the Higher Education Research Institute's 2007-2008 Faculty Survey, we employ hierarchical generalized linear modeling to analyze data from 4,832 science, technology, engineering, and mathematics (STEM) faculty across 194 institutions to examine how organizational citizenship behavior theory and social exchange theory relate to mentoring students in research. Key findings show that faculty who work in the life sciences and those who receive government funding for their research are more likely to involve undergraduates in their research project(s). In addition, faculty at liberal arts or historically Black colleges are significantly more likely to involve undergraduate students in research. Implications for advancing undergraduate research opportunities are discussed
Depression following adult, non-penetrating traumatic brain injury: A meta-analysis examining methodological variables and sample characteristics
BACKGROUND: Depression is one of the most frequently reported psychological problems following TBI, however prevalence estimates vary widely. Methodological and sampling differences may explain some of this variability, but it is not known to what extent. METHODS: Data from 99 studies examining the prevalence of clinically diagnosed depression (MDD/dysthymia) and self-reports of depression (clinically significant cases or depression scale scores) following adult, non-penetrating TBI were analysed, taking into consideration diagnostic criteria, measure, post-injury interval, and injury severity. RESULTS: Overall, 27% of people were diagnosed with MDD/dysthymia following TBI and 38% reported clinically significant levels of depression when assessed with self-report scales. Estimates of MDD/dysthymia varied according to diagnostic criteria (ICD-10: 14%; DSM-IV: 25%; DSM-III: 47%) and injury severity (mild: 16%; severe: 30%). When self-report measures were used, the prevalence of clinically significant cases of depression differed between scales (HADS: 32%; CES-D: 48%) method of administration (phone: 26%; mail 46%), post-injury interval (range: 33-42%), and injury severity (mild: 64%; severe: 39%). CONCLUSION: Depression is very common after TBI and has the potential to impact on recovery and quality of life. However, the diagnostic criteria, measure, time post-injury and injury severity, all impact on prevalence rates and must therefore be considered for benchmarking purposes.A.J. Osborn, J.L. Mathias, A.K. Fairweather-Schmid
Effect of Reynolds number on particle interaction and agglomeration in turbulent channel flow
The work described in this paper employs large eddy simulation and a discrete element method to study turbulent particle-laden channel flows at low concentrations (particle volume fraction 10ā4ā10ā5), including particle dispersion, collision and agglomeration. Conventional understanding of such flows is that particle interactions are negligible, this work however demonstrates that such interactions are common at large Stokes numbers in turbulent flow. The particle-particle interaction model is based on the Hertz-Mindlin approach with Johnson-Kendall-Roberts cohesion to allow the simulation of cohesive forces in a dry air flow. The influence of different flow Reynolds numbers, and therefore the impact of fluid turbulence, on agglomeration behaviour is investigated. The agglomeration rate is found to be strongly influenced by the flow Reynolds number, with most of the particle-particle interactions taking place at locations close to the channel walls, aided by the higher turbulence levels and concentration of particles in these regions
A decrease in iron availability to human gut microbiome reduces the growth of potentially pathogenic gut bacteria: an in vitro colonic fermentation study
Iron-supplements are widely consumed; however most of the iron is not absorbed and enters the colon where potentially pathogenic bacteria can utilise it for growth. This study investigated the effect of iron availability on human gut microbial composition and function using an in vitro colonic fermentation model inoculated with faecal microbiota from healthy adult donors, as well as examining the effect of iron on the growth of individual gut bacteria. Batch fermenters were seeded with fresh faecal material and supplemented with the iron chelator, bathophenanthroline disulphonic acid (BPDS). Samples were analysed at regular intervals to assess impact on the gut bacterial communities. The growth of Escherichia coli and Salmonella Typhimurium was significantly impaired when cultured independently in iron-deficient media. In contrast, depletion of iron did not affect the growth of the beneficial species, Lactobacillus rhamnosus, when cultured independently. Analysis of the microbiome composition via 16S-based metataxonomics indicated that under conditions of iron chelation, the relative abundance decreased for several taxa, including a 10% decrease in Escherichia and a 15% decrease in Bifidobacterium. Metabolomics analysis using 1 HNMR indicated that the production of SCFAs was reduced under iron-limited conditions. These results support previous studies demonstrating the essentiality of iron for microbial growth and metabolism, but, in addition, they indicate that iron chelation changes the gut microbiota profile and influences human gut microbial homeostasis through both compositional and functional changes
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