170 research outputs found

    Leopard Panthera pardus density in southern Mozambique: evidence from spatially explicit capture-recapture in Xonghile Game Reserve

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    Rigorous status estimates of populations of large carnivores are necessary to inform their management and help evaluate the effectiveness of conservation interventions. The African leopard Panthera pardus faces rising anthropogenic pressures across most of its contracting sub-Saharan range, but the scarcity of reliable population estimates means that management decisions often have to rely on expert opinion rather than being based on sound evidence. This is particularly true for Mozambique, where little is known about the ecology or conservation status of leopard populations as a result of prolonged armed conflict. We used camera trapping and spatially explicit capture-recapture models to provide a leopard density estimate in Xonghile Game Reserve in southern Mozambique, which is part of the Greater Limpopo Transfrontier conservation initiative. The estimated population density was 2.60 +/- SE 0.96 leopards/100 km(2). Our study provides a baseline leopard density for the region and the first empirical density estimate for southern Mozambique. Our results also suggest that current methods used to set trophy hunting quotas for leopards, both in Mozambique and elsewhere in Africa, may be leading to unsustainable quotas, which highlights the importance of robust empirical data in guiding conservation policy

    Self-help interventions for anxiety disorders: An overview.

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    Anxiety disorders are highly prevalent and are associated with a marked impairment in quality of life and a huge economic cost to society. Unfortunately, a considerable number of people who struggle with anxiety do not seek or receive adequate treatment. Self-help interventions have been proposed to constitute a relatively cheap, effective, efficient, and low-threshold intervention for anxiety disorders. This paper offers a critical discussion of their advantages and disadvantages and the evidence for their effectiveness. We conclude that guided self-help can play a major role in mental health care for patients with anxiety disorders. However, several research questions need to be answered before broad-scale dissemination is possible. The Internet will continue to play a prominent role in the further development of this field of research and clinical practice

    Space Telescope and Optical Reverberation Mapping Project. VII. Understanding the Ultraviolet Anomaly in NGC 5548 with X-Ray Spectroscopy

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    During the Space Telescope and Optical Reverberation Mapping Project observations of NGC 5548, the continuum and emission-line variability became decorrelated during the second half of the six-month-long observing campaign. Here we present Swift and Chandra X-ray spectra of NGC 5548 obtained as part of the campaign. The Swift spectra show that excess flux (relative to a power-law continuum) in the soft X-ray band appears before the start of the anomalous emission-line behavior, peaks during the period of the anomaly, and then declines. This is a model-independent result suggesting that the soft excess is related to the anomaly. We divide the Swift data into on- and off-anomaly spectra to characterize the soft excess via spectral fitting. The cause of the spectral differences is likely due to a change in the intrinsic spectrum rather than to variable obscuration or partial covering. The Chandra spectra have lower signal-to-noise ratios, but are consistent with the Swift data. Our preferred model of the soft excess is emission from an optically thick, warm Comptonizing corona, the effective optical depth of which increases during the anomaly. This model simultaneously explains all three observations: the UV emission-line flux decrease, the soft-excess increase, and the emission-line anomaly

    Global maps of soil temperature.

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    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km <sup>2</sup> resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km <sup>2</sup> pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    TRY plant trait database – enhanced coverage and open access

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    Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Licófitas e monilófitas das Unidades de Conservação da Usina Hidroelétrica - UHE de Tucuruí, Parå, Brasil

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    Highly Accurate Synchronization Over Ethernet

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    Time and timing is everything and everywhere from catching a train to synchronizing machines in a production hall. The key issue of all communicating systems is synchronization. Today’s sensor networks are growing larger and more complex every day, creating a demand for simple and scalable networks, whereby data and clock distribution is shared by means of one single interface. High end systems like PET scanners demand a high level of synchronization up to 50 picoseconds or less. This thesis focuses on highly accurate, sub nanosecond synchronization of system clocks for large sensor networks using a single interface for both high speed data communication and clock distribution. In this work different technologies for frequency matching, phase steering and phase measurement for FPGA implementations are compared. The verification and optimization of today’s best technology is presented, including a novel Wheatstone based technique.Embedded systemsMicroelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc

    Habitat use responses of the African leopard in a human-disturbed region of rural Mozambique

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    Leopard (Panthera pardus) populations across Africa are increasingly exposed to high levels of anthropogenic disturbance, and information on habitat use responses of leopards in human-disturbed landscapes can help inform status assessments and guide conservation interventions. Unfortunately, however, few studies have investigated leopard ecology in human-disturbed landscapes, particularly in Africa. We employed camera-trapping and occupancy modelling to provide inferences on leopard habitat use in a National Park in Mozambique impacted by subsistence farming and bushmeat poaching. Replicated detection/non-detection occupancy surveys were used to estimate site use by leopards in a representative area of the park, and to investigate relative impacts of environmental, conspecific and anthropogenic factors on leopard occurrence. The proportion of sites used by leopards was estimated at 0.814 (SE = 0.093), which is approximately twice the occupancy previously reported for lion (44%) and cheetah (40%) in the same area. Leopard presence was not strongly predicted by any of the covariates, indicating there were no strong limiting factors. While leopards generally avoided human settlements and were positively predicted by prey, results suggest that there was sufficient prey and space for the species to use most available habitats. The greatest contributing factor to leopard habitat use was a positive correlation with bushmeat poachers and lions. It is possible that these other predators provide a more accurate indicator of prey availability than our single-species indicator based on camera trap data. This study provides important novel information on habitat use by leopards in a system disturbed by rural human subsistence activities in Africa
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