62 research outputs found

    Factors affecting the availability of invertebrate food for the chough, Pyrrhocorax pyrrhocorax L

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    Most of the fieldwork for this study was conducted on the island of Islay, in the Inner Hebrides, the stronghold of the chough, Pyrrhocorax pyrrhocorax L., in Scotland. The aims of this study were to provide baseline data on the phenology of potential invertebrate foods of the chough, and to provide a greater understanding of the factors affecting these invertebrate populations. The literature concerning (a) the chough in Britain and its feeding ecology, (b) the invertebrate fauna of pasture, (c) the invertebrates associated with cow dung, (d) ivermectin and its effect on the invertebrate fauna associated with cattle dung, and (e) the multivariate analysis methods used in this study, is reviewed. An area of heather moorland and four pastures were selected on Islay. Invertebrates were collected from these sites between January 1988 and November 1989 using pitfall traps, and by sampling soil and cow pats. The data obtained was analysed using two multivariate analysis methods -Two-Way-Indicator-Species- Analysis (TWINSPAN) and Detrended Correspondence Analysis (DECORANA). Information on 62 surface-active taxa was obtained from pitfall trapping. Although seasonal taxa assemblages were recognized, the distribution of the invertebrate communities was primarily related to soil moisture content. Grazing intensity and seasonality were also important factors determining the composition of the invertebrate fauna at each site. The taxa active during the summer and winter at the two sand grassland sites, did not appear to differ as markedly as at the other sites sampled. Figures showing the seasonal activity of some of the frequently occurring taxa at each site considered potential chough prey items are provided. Surface-active potential chough food items were present, at all the sites investigated, throughout the year. Soil-sampling provided information on 34 taxa. As with the surface-active fauna, the primary factor influencing the soil fauna was soil moisture content. The time of year was also an important factor governing the soil fauna composition, with the majority of taxa occurring in low numbers during the summer months at all the sites sampled. Figures indicating the seasonal occurrences of some of the taxa considered potential chough prey items at each site are provided. Soil did not appear to be a good source of potential prey items for the chough during the summer months, although, as a result of seasonal increases in size, certain taxa, e.g. Tipulidae larvae, may have been more 'worthwhile' prey items at this time of year than at any other. Information on 54 taxa was obtained from sampling cow dung. Seasonality and age of the dung were very important in determining the composition of the dung fauna. The seasonal variations in the fauna associated with the cow pats are described. Potential chough prey items were associated with cow dung, in any stage of decay, throughout most of the year. Only during the period from October/November to January did there appear to be a lack of suitably sized potential prey items in the dung. The 'summer' months, when fresh dung contained large numbers of beetle adults and developing fly larvae, and late autumn, when pats deposited during the summer months are old enough for the large numbers of Aphodius spp. larvae present to have attained a reasonable size, were considered to be the times at which cow dung presented the best feeding opportunities for the chough. Fifty taxa were identified in samples of chough faeces. Multivariate analysis of these data indicated that the seasonal availability of prey items was the most important factor influencing chough diet throughout the year. Soil-dwelling Tipulidae (January to July) and Bibionidae (January to April) larvae, dung-associated insects (during the spring, and late summer and autumn), and surface-active insects (during the summer) were important invertebrate components of the diet. Cereal grains were extremely important supplementary food items during the early winter months, when invertebrate availability was low. An experiment was conducted at the College to investigate the effects on the dung fauna of spiking cow dung with 2.0, 1.0, or 0.5 mg/kg dung of ivermectin. Pats were placed on pasture between May and September 1988. The pats were lifted, and the soil beneath sampled, after 15 to 90 days exposure. A total of 65 taxa were identified. These data were analysed using TWINSPAN, DECORANA and Canonical Correspondence Analysis (CANOCO). The major factors determining the invertebrate fauna of the pats were length of exposure, exposure date, and ivermectin presence/absence. Ivermectin markedly affected the fauna associated with the pats. Pats exposed in June and August degraded faster than those exposed in May or September. In June, the ivermectin-treated pats degraded significantly slower than the control pats. An attempt to extract ivermectin from cow dung for analysis by high-performance liquid chromatography is described. This proved unsuccessful and the reasons for this failure, and possible improvements, are discussed. The main conclusions of this study are: (1) that Tipulidae larvae are extremely important components of the chough's diet on Islay, and that the climatic conditions of the island favour these insects; (2) livestock farming on Islay, especially the out-wintering of cattle, provides essential feeding opportunities for the chough, as, (a) gazing animals produce the short sward preferred by the chough as a feeding habitat, (b) large numbers of insects are associated with the dung of these animals, and (c) supplementary feed provided for the cattle in winter also provides an essential alternative food source for the chough at a critical time; (3) the chough's preference on Islay for feeding in sandy, coastal pasture is due to the fact that these sites, (a) contain a variety of suitable invertebrate prey items throughout most of the year, (b) are normally intensively grazed and so contain large amounts of dung with its associated fauna, and (c) are used for out-wintering cattle and therefore cereal grains can be found there; (4) treating cattle with ivermectin could have an adverse effect on the chough as it reduces the number and variety of invertebrates associated with the dung, an important food source for the birds, especially in spring and autumn

    A multinational, multi-institutional study of assessment of programming skills of first-year CS students

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    In computer science, an expected outcome of a student's education is programming skill. This working group investigated the programming competency students have as they complete their first one or two courses in computer science. In order to explore options for assessing students, the working group developed a trial assessment of whether students can program. The underlying goal of this work was to initiate dialog in the Computer Science community on how to develop these types of assessments. Several universities participated in our trial assessment and the disappointing results suggest that many students do not know how to program at the conclusion of their introductory courses. For a combined sample of 216 students from four universities, the average score was 22.89 out of 110 points on the general evaluation criteria developed for this study. From this trial assessment we developed a framework of expectations for first-year courses and suggestions for further work to develop more comprehensive assessments

    Improving the science-policy dialogue to meet the challenges of biodiversity conservation: having conversations rather than talking at one-another

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    A better, more effective dialogue is needed between biodiversity science and policy to underpin the sustainable use and conservation of biodiversity. Many initiatives exist to improve communication, but these largely conform to a ‘linear’ or technocratic model of communication in which scientific “facts” are transmitted directly to policy advisers to “solve problems”. While this model can help start a dialogue, it is, on its own, insufficient, as decision taking is complex, iterative and often selective in the information used. Here, we draw on the literature, interviews and a workshop with individuals working at the interface between biodiversity science and government policy development to present practical recommendations aimed at individuals, teams, organisations and funders. Building on these recommendations, we stress the need to: (a) frame research and policy jointly; (b) promote inter- and trans-disciplinary research and “multi-domain” working groups that include both scientists and policy makers from various fields and sectors; (c) put in place structures and incentive schemes that support interactive dialogue in the long-term. These are changes that are needed in light of continuing loss of biodiversity and its consequences for societal dependence on and benefits from nature

    The opto-mechanical design of the GMT-Consortium Large Earth Finder (G-CLEF)

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    The GMT-Consortium Large Earth Finder (G-CLEF) will be part of the first generation instrumentation suite for the Giant Magellan Telescope (GMT). G-CLEF is a general purpose echelle spectrograph operating in the optical passband with precision radial velocity (PRV) capability. The measurement precision goal of G-CLEF is 10 cm/sec; necessary for the detection of Earth analogues. This goal imposes challenging stability requirements on the optical mounts and spectrograph support structures especially when considering the instrument's operational environment. G-CLEF's accuracy will be influenced by changes in temperature and ambient air pressure, vibration, and micro gravity-vector variations caused by normal telescope motions. For these reasons we have chosen to enclose G-CLEF's spectrograph in a wellinsulated, vibration-isolated vacuum chamber in a gravity invariant location on GMT's azimuth platform. Additional design constraints posed by the GMT telescope include; a limited space envelope, a thermal leakage ceiling, and a maximum weight allowance. Other factors, such as manufacturability, serviceability, available technology, and budget are also significant design drivers. G-CLEF will complete its Critical Design phase in mid-2018. In this paper, we discuss the design of GCLEF's optical mounts and support structures including the choice of a low-CTE carbon-fiber optical bench. We discuss the vacuum chamber and vacuum systems. We discuss the design of G-CLEF's insulated enclosure and thermal control systems which simultaneously maintain the spectrograph at milli-Kelvin level stability and limit thermal leakage into the telescope dome. Also discussed are micro gravity-vector variations caused by normal telescope slewing, their uncorrected influence on image motion, and how they are dealt with in the design. We discuss G-CLEF's front-end assembly and fiber-feed system as well as other interface, integration and servicing challenges presented by the telescope, enclosure, and neighboring instrumentation. This work has been supported by the GMTO Corporation, a non-profit organization operated on behalf of an international consortium of universities and institutions: Arizona State University, Astronomy Australia Ltd, the Australian National University, the Carnegie Institution for Science, Harvard University, the Korea Astronomy and Space Science Institute, the São Paulo Research Foundation, the Smithsonian Institution, the University of Texas at Austin, Texas AM University, the University of Arizona, and the University of Chicago

    Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders

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    Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyper-activity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.Peer reviewe

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Tracking development assistance for health and for COVID-19: a review of development assistance, government, out-of-pocket, and other private spending on health for 204 countries and territories, 1990-2050

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    Background The rapid spread of COVID-19 renewed the focus on how health systems across the globe are financed, especially during public health emergencies. Development assistance is an important source of health financing in many low-income countries, yet little is known about how much of this funding was disbursed for COVID-19. We aimed to put development assistance for health for COVID-19 in the context of broader trends in global health financing, and to estimate total health spending from 1995 to 2050 and development assistance for COVID-19 in 2020. Methods We estimated domestic health spending and development assistance for health to generate total health-sector spending estimates for 204 countries and territories. We leveraged data from the WHO Global Health Expenditure Database to produce estimates of domestic health spending. To generate estimates for development assistance for health, we relied on project-level disbursement data from the major international development agencies' online databases and annual financial statements and reports for information on income sources. To adjust our estimates for 2020 to include disbursements related to COVID-19, we extracted project data on commitments and disbursements from a broader set of databases (because not all of the data sources used to estimate the historical series extend to 2020), including the UN Office of Humanitarian Assistance Financial Tracking Service and the International Aid Transparency Initiative. We reported all the historic and future spending estimates in inflation-adjusted 2020 US,2020US, 2020 US per capita, purchasing-power parity-adjusted USpercapita,andasaproportionofgrossdomesticproduct.Weusedvariousmodelstogeneratefuturehealthspendingto2050.FindingsIn2019,healthspendinggloballyreached per capita, and as a proportion of gross domestic product. We used various models to generate future health spending to 2050. Findings In 2019, health spending globally reached 8. 8 trillion (95% uncertainty interval UI] 8.7-8.8) or 1132(11191143)perperson.Spendingonhealthvariedwithinandacrossincomegroupsandgeographicalregions.Ofthistotal,1132 (1119-1143) per person. Spending on health varied within and across income groups and geographical regions. Of this total, 40.4 billion (0.5%, 95% UI 0.5-0.5) was development assistance for health provided to low-income and middle-income countries, which made up 24.6% (UI 24.0-25.1) of total spending in low-income countries. We estimate that 54.8billionindevelopmentassistanceforhealthwasdisbursedin2020.Ofthis,54.8 billion in development assistance for health was disbursed in 2020. Of this, 13.7 billion was targeted toward the COVID-19 health response. 12.3billionwasnewlycommittedand12.3 billion was newly committed and 1.4 billion was repurposed from existing health projects. 3.1billion(22.43.1 billion (22.4%) of the funds focused on country-level coordination and 2.4 billion (17.9%) was for supply chain and logistics. Only 714.4million(7.7714.4 million (7.7%) of COVID-19 development assistance for health went to Latin America, despite this region reporting 34.3% of total recorded COVID-19 deaths in low-income or middle-income countries in 2020. Spending on health is expected to rise to 1519 (1448-1591) per person in 2050, although spending across countries is expected to remain varied. Interpretation Global health spending is expected to continue to grow, but remain unequally distributed between countries. We estimate that development organisations substantially increased the amount of development assistance for health provided in 2020. Continued efforts are needed to raise sufficient resources to mitigate the pandemic for the most vulnerable, and to help curtail the pandemic for all. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd
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