3,008 research outputs found
Effects of Landscape Composition and Configuration on Migrating Songbirds: Inference from an Individual-Based Model
The behavior of long-distance migrants during stopover is constrained by the need to quickly and safely replenish energetic reserves. Replenishing fuel stores at stopover sites requires adjusting to unfamiliar landscapes with little to no information about the distribution of resources. Despite their critical importance to the success of songbird migration, the effects of landscape composition and configuration on fuel deposition rates (FDR [g/d]), the currency of migration, has not been tested empirically. Our objectives were to understand the effects of heterogeneous landscapes on FDR of forest-dwelling songbirds during spring migration. The results of field experiments were used to parameterize a spatially explicit, individual-based model of forest songbird movement and resulting FDR. Further field experiments were used to validate the results from the individual-based model. In simulation experiments, we altered a Gulf South landscape in a factorial design to predict the effects of future patterns under different scenarios of land use change in which the abundance of high-quality hardwood habitat and the spatial aggregation of habitat varied. Simulated FDR decreased as the amount of hardwood in the landscape decreased from 41% to 22% to 12%. Further, migrants that arrived in higher-quality habitat types gained more mass. Counter to our expectations, FDR was higher with lower spatial aggregation of habitat. Differences in refueling rates may be most influenced by whether or not an individual experiences an initial searching cost after landing in poor-quality habitat. Therefore, quickly locating habitat with sufficient food resources at each stopover may be the most important factor determining a successful migration. Our findings provide empirical evidence for the argument that hardwood forest cover is a primary determinant of the quality of a stopover site in this region. This study represents the first effort to empirically quantify FDRs based on the configuration of landscapes
Developing a typology of interventions to support doctorsâ mental health and wellbeing
Background:Â The problem of mental ill-health in doctors is complex, accentuated by the COVID-19 pandemic, and impacts on healthcare provision and broader organisational performance. There are many interventions to address the problem but currently no systematic way to categorise them, which makes it hard to describe and compare interventions. As a result, implementation tends to be unfocussed and fall short of the standards developed for implementing complex healthcare interventions. This study aims to develop: 1) a conceptual typology of workplace mental health and wellbeing interventions and 2) a mapping tool to apply the typology within research and practice.
Methods:Â Typology development was based on iterative cycles of analysis of published and in-practice interventions, incorporation of relevant theories and frameworks, and team and stakeholder group discussions.
Results:Â The newly developed typology and mapping tool enable interventions to be conceptualised and/or mapped into different categories, for example whether they are designed to be largely preventative (by either improving the workplace or increasing personal resources) or to resolve problems after they have arisen. Interventions may be mapped across more than one category to reflect the nuance and complexity in many mental health and wellbeing interventions. Mapping of interventions indicated that most publications have not clarified their underlying assumptions about what causes outcomes or the theoretical basis for the intervention.
Conclusion:Â The conceptual typology and mapping tool aims to raise the quality of future research and promote clear thinking about the nature and purpose of interventions, In doing so it aims to support future research and practice in planning interventions to improve the mental health and wellbeing of doctors
The response of understory herbaceous plants to nitrogen fertilization in forests of different land-use history
Limits on Arcminute Scale Cosmic Microwave Background Anisotropy with the BIMA Array
We have used the Berkeley-Illinois-Maryland-Association (BIMA) millimeter
array outfitted with sensitive cm-wave receivers to search for Cosmic Microwave
Background (CMB) anisotropies on arcminute scales. The interferometer was
placed in a compact configuration which produces high brightness sensitivity,
while providing discrimination against point sources. Operating at a frequency
of 28.5 GHz, the FWHM primary beam of the instrument is 6.6 arcminutes. We have
made sensitive images of seven fields, five of which where chosen specifically
to have low IR dust contrast and be free of bright radio sources. Additional
observations with the Owens Valley Radio Observatory (OVRO) millimeter array
were used to assist in the location and removal of radio point sources.
Applying a Bayesian analysis to the raw visibility data, we place limits on CMB
anisotropy flat-band power Q_flat = 5.6 (+3.0 -5.6) uK and Q_flat < 14.1 uK at
68% and 95% confidence. The sensitivity of this experiment to flat band power
peaks at a multipole of l = 5470, which corresponds to an angular scale of
approximately 2 arcminutes. The most likely value of Q_flat is similar to the
level of the expected secondary anisotropies.Comment: 15 pages, 5 figures, LaTex, aas2pp4.sty, ApJ submitte
Predicting Microstegium vimineum invasion in natural plant communities of the southern Blue Ridge Mountains, USA
Maximizing the impact of malaria funding through allocative efficiency: using the right interventions in the right locations.
BACKGROUND: The high burden of malaria and limited funding means there is a necessity to maximize the allocative efficiency of malaria control programmes. Quantitative tools are urgently needed to guide budget allocation decisions. METHODS: A geospatial epidemic model was coupled with costing data and an optimization algorithm to estimate the optimal allocation of budgeted and projected funds across all malaria intervention approaches. Interventions included long-lasting insecticide-treated nets (LLINs), indoor residual spraying (IRS), intermittent presumptive treatment during pregnancy (IPTp), seasonal mass chemoprevention in children (SMC), larval source management (LSM), mass drug administration (MDA), and behavioural change communication (BCC). The model was applied to six geopolitical regions of Nigeria in isolation and also the nation as a whole to minimize incidence and malaria-attributable mortality. RESULTS: Allocative efficiency gains could avert approximately 84,000 deaths or 15.7 million cases of malaria in Nigeria over 5Â years. With an additional US$300 million available, approximately 134,000 deaths or 37.3 million cases of malaria could be prevented over 5Â years. Priority funding should go to LLINs, IPTp and BCC programmes, and SMC should be expanded in seasonal areas. To minimize mortality, treatment expansion is critical and prioritized over some LLIN funding, while to minimize incidence, LLIN funding remained a priority. For areas with lower rainfall, LSM is prioritized over IRS but MDA is not recommended unless all other programmes are established. CONCLUSIONS: Substantial reductions in malaria morbidity and mortality can be made by optimal targeting of investments to the right malaria interventions in the right areas
iMembrane: homology-based membrane-insertion of proteins
Summary: iMembrane is a homology-based method, which predicts a membrane protein's position within a lipid bilayer. It projects the results of coarse-grained molecular dynamics simulations onto any membrane protein structure or sequence provided by the user. iMembrane is simple to use and is currently the only computational method allowing the rapid prediction of a membrane protein's lipid bilayer insertion. Bilayer insertion data are essential in the accurate structural modelling of membrane proteins or the design of drugs that target them
Ending malnutrition in all its forms requires scaling up proven nutrition interventions and much more: a 129-country analysis.
BackgroundSustainable Development Goal (SDG) 2.2 calls for an end to all forms of malnutrition, with 2025 targets of a 40% reduction in stunting (relative to 2012), for wasting to occur in less than 5% of children, and for a 50% reduction in anaemia in women (15-49âyears). We assessed the likelihood of countries reaching these targets by scaling up proven interventions and identified priority interventions, based on cost-effectiveness.MethodsFor 129 countries, the Optima Nutrition model was used to compare 2019-2030 nutrition outcomes between a status quo (maintained intervention coverage) scenario and a scenario where outcome-specific interventions were scaled up to 95% coverage over 5Â years. The average cost-effectiveness of each intervention was calculated as it was added to an expanding package of interventions.ResultsOf the 129 countries modelled, 46 (36%), 66 (51%) and 0 (0%) were on track to achieve the stunting, wasting and anaemia targets respectively. Scaling up 18 nutrition interventions increased the number of countries reaching the SDG 2.2 targets to 50 (39%), 83 (64%) and 7 (5%) respectively. Intermittent preventative treatment of malaria during pregnancy (IPTp), infant and young child feeding education, vitamin A supplementation and lipid-based nutrition supplements for children produced 88% of the total impact on stunting, with average costs per case averted of US267, US1795 when interventions were consecutively scaled up, respectively. Vitamin A supplementation and cash transfers produced 100% of the total global impact on prevention of wasting, with average costs per case averted of US19,427, respectively. IPTp, iron and folic acid supplementation for non-pregnant women, and multiple micronutrient supplementation for pregnant women produced 85% of the total impact on anaemia prevalence, with average costs per case averted of US35 and US$47, respectively.ConclusionsPrioritising nutrition investment to the most cost-effective interventions within the country context can maximise the impact of funding. A greater focus on complementing nutrition-specific interventions with nutrition-sensitive ones that address the social determinants of health is critical to reach the SDG targets
WWU Lifestyles Project: Patterns of Alcohol and Drug Consumption and Consequences among Western Washington University Students
Executive Summary: This report, besides presenting the Lifestyles Project findings, summaries and discussion, contains two important Appendices. Appendix A consists of Western\u27s Comprehensive Plan to Combat Student Alcohol Abuse, Including Underage Drinking, as as submitted to the Higher Education Coordinating Board. Appendix B consists of preliminary findings on the effectiveness of the Wellness Hall. The executive summary includes summaries of all three of these sections. Lifestyles Project Findings The WWU Lifestyles Project surveyed a randomly selected, stratified sample of 2500 students enrolled at Western during spring quarter, 1992, regarding their use of alcohol and drugs, the consequences of using, and motivation to change patterns of use. Completed questionnaires were received from 1217 students for a nearly 50% return rate Overall, the results of the survey suggested that a large proportion of the student population (76.6 %), including those under the legal age, drink alcohol at least once a month. While factors such as class standing and age affected level of alcohol consumption, differences by gender were the most dramatic. Generally speaking, while males and females keep pace in their frequency and quantity of alcohol consumption up to a point, at higher levels of consumption men tend to drink more often and in larger quantities than females. Moreover, males tend to report the highest rates of at risk drinking; that is, drinking at a binge level (5+ drinks at one setting) and higher. At Western, as nationwide, alcohol is the drug of choice for college students, with survey respondents reporting relatively scant use of drugs like cocaine and LSD, and low use of marijuana. Patterns of alcohol use at Western appear threefold: 1) nearly a quarter of survey respondents reported no drinking at all in the previous month; 2) of respondents indicating any frequency of drinking whatsoever (about three-quarters of the survey population), 31.3% reported drinking 1-2 drinks and 22.7% reported drinking 3-4 drinks on typical occasions, which places them in a low to moderate drinking norm; and 3) of respondents indicating any frequency of drinking whatsoever, 29.8% reported binge drinking on typical occasions and 57.2% reported binge drinking on peak occasions. This last drinking pattern suggests that an alcohol environment may exist at Western that contributes to substantial social and academic risks for Western students. Issues of concern include that a substantial percentage (67.4%) of those who report any frequency of drinking whatsoever were under the legal drinking age, and that well over half of the respondents overall (64.0%) reported at least one alcohol-related problem in the last six months. Of particular relevance to the academic mission of university life are the discrepancies found between students\u27 perception for risk of negative academic consequences due to alcohol-related effects and the actual occurrence of those outcomes. Actual occurrences were nearly double and sometimes treble that of perceived risk. These findings suggest that perception of vulnerability to negative alcohol effects may differ enough from actual occurrences of negative alcohol effects to pose a threat to students\u27 academic success and persistence. Although the university has raised awareness of campus alcohol and drug policies and programs--nearly two-thirds of respondents reported they knew of such effortsâmost respondents stated that official university policies and programs do not effect their own personal levels of use. Comprehensive Plan to Combat Student Alcohol Abuse In response to the alcohol predicament on campus, WWU has developed a comprehensive plan for combating student alcohol abuse and its consequent negative academic, health, and social outcomes. WWU\u27s plan anticipates improvement in reducing the incidence of student alcohol abuse both on and around campus because it is based on the public health model, which views both individual students who drink and the environments in which they drink as the targets for major interventions. Based on the systems approach inherent within the public health model, WWU will utilize four major strategies to decrease both individual problem use of alcohol and the drinking norms on campus: 1) primary prevention seeks to reduce risk for alcohol problems or prevent the occurrence of alcohol abuse and/or underage drinking before those problems occur; 2) secondary prevention programs seek to halt, reverse, or retard alcohol abuse problems after they have occurred, but before they lead to life-altering or life-threatening consequences; 3) tertiary prevention efforts seek to reduce the risks of severe alcohol abuse, and 4) health promotion efforts seek to develop positive environments and community policies, rules, and norms that support and encourage students who are already making choices not to abuse alcohol or to drink illegally thereby leading to the creation of a new critical mass who do not view alcohol abuse as a typical and expected feature of college life. (See Appendix A.) Wellness Hall: Preliminary Findings University Residences and the Primary Prevention and Wellness Center collaborated to open the wellness residence hall at WWU in Fall Quarter, 1993. The creating of four floors of Nash Hall as an alcohol and drug free zone was made possible by a FIPSE grant. Participating students signed substance-free living agreements, thereby voluntarily committing to abstain from the use of alcohol, tobacco or drugs while residing on campus. During its first quarter of existence, there were no violations of this voluntary code. Furthermore, some preliminary information--reduced vandalism and fewer alcohol related incidents--suggests that students in the wellness community are consuming less alcohol than their counterparts in a correspondent freshmen residence hall. An initial administration of the CORE alcohol and drug survey also suggests that students residing in the wellness community are choosing to consume less alcohol
A Multi-Epoch VLBI Survey of the Kinematics of CJF Sources; Part I: Model-Fit Parameters and Maps
Context: This is the first of a series of papers presenting VLBI observations
of the 293 Caltech-Jodrell Bank Flat-Spectrum (hereafter CJF) sources and their
analysis. Aims: One of the major goals of the CJF is to make a statistical
study of the apparent velocities of the sources. Methods: We have conducted
global VLBI and VLBA observations at 5 GHz since 1990, accumulating thirteen
separate observing campaigns. Results: We present here an overview of the
observations, give details of the data reduction and present the source
parameters resulting from a model-fitting procedure. For every source at every
observing epoch, an image is shown, built up by restoring the model-fitted
components, convolved with the clean beam, into the residual image, which was
made by Fourier transforming the visibility data after first subtracting the
model-fitted components in the uv-plane. Overplotted we show symbols to
represent the model components. Conclusions: We have produced VLBI images of
all but 5 of the 293 sources in the complete CJF sample at several epochs and
investigated the kinematics of 266 AGN.Comment: Figure 1 and Table 2 are only available in electronic form at the CDS
and soon at http://www.mpifr-bonn.mpg.de/staff/sbritzen/cjf.htm
- âŠ