5,290 research outputs found

    Temporal variation in bird assemblages: how representative is a one-year snapshot?

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    Bird assemblages generally are no longer regarded as stable entities, but rather as fluctuating in response to many factors. Australia’s highly variable climate is likely to result in a high degree of dynamism in its bird assemblages, yet few studies have investigated variation on an inter-annual temporal scale. We compared two year-long samples of the bird assemblages of a series of highly fragmented buloke Allocasuarina luehmannii (Casuarinaceae)woodland remnants in south-eastern Australia, the first sample taken in 1994–1995 and the second in 2001–2002. Bird densities were almost three times higher in the second period than in the first. Mean species richness also was significantly higher. Species richness of each individual site was unrelated between the two years. Minimum species turnover was 63% and was higher, on average, for migratory and nomadic than for sedentary species. Therefore, site-level bird assemblage composition was markedly different between the two survey periods and, on average, the assemblage composition of each site bore greater resemblance to those of other sites in the same year than to that of the same site in the other survey period. Most species changed substantially in their distribution among remnants between the two periods. The change in distribution of most species did not differ significantly from that expected if the species had redistributed at random among the sites. This suggests that although the remnant vegetation of the area is highly fragmented with minimal interpatch connectivity, bird movements among remnants must be relatively frequent. Interannual variability in Australian bird assemblages may be higher than is commonly recognized. In such dynamic systems, we must be cautious when extrapolating from the findings of short-term studies to longer temporal scales, especially in relation to conservation management. A greater understanding of the processes driving distributional patterns is likely to enable better predictions of species’ responses to habitat change

    The quantum probability ranking principle for information retrieval

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    While the Probability Ranking Principle for Information Retrieval provides the basis for formal models, it makes a very strong assumption regarding the dependence between documents. However, it has been observed that in real situations this assumption does not always hold. In this paper we propose a reformulation of the Probability Ranking Principle based on quantum theory. Quantum probability theory naturally includes interference effects between events. We posit that this interference captures the dependency between the judgement of document relevance. The outcome is a more sophisticated principle, the Quantum Probability Ranking Principle, that provides a more sensitive ranking which caters for interference/dependence between documents’ relevanc

    Arresting woodland bird decline in Australian agricultural landscapes: potential application of the European agri-environment model

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    This paper considered the applicability of the European model of land stewardship payments, in particular its support for biodiversity conservation in agricultural landscapes, to an Australian context. More broadly, the research approach described in the paper may also be applied to assessing the suitability of overseas stewardship schemes to the provision of any ecoservice in Australia, such as carbon sequestration and floodwater regulation

    Measuring Accuracy of Triples in Knowledge Graphs

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    An increasing amount of large-scale knowledge graphs have been constructed in recent years. Those graphs are often created from text-based extraction, which could be very noisy. So far, cleaning knowledge graphs are often carried out by human experts and thus very inefficient. It is necessary to explore automatic methods for identifying and eliminating erroneous information. In order to achieve this, previous approaches primarily rely on internal information i.e. the knowledge graph itself. In this paper, we introduce an automatic approach, Triples Accuracy Assessment (TAA), for validating RDF triples (source triples) in a knowledge graph by finding consensus of matched triples (among target triples) from other knowledge graphs. TAA uses knowledge graph interlinks to find identical resources and apply different matching methods between the predicates of source triples and target triples. Then based on the matched triples, TAA calculates a confidence score to indicate the correctness of a source triple. In addition, we present an evaluation of our approach using the FactBench dataset for fact validation. Our findings show promising results for distinguishing between correct and wrong triples

    Thermal conduction and particle transport in strong MHD turbulence, with application to galaxy-cluster plasmas

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    We investigate field-line separation in strong MHD turbulence analytically and with direct numerical simulations. We find that in the static-magnetic-field approximation the thermal conductivity in galaxy clusters is reduced by a factor of about 5-10 relative to the Spitzer thermal conductivity of a non-magnetized plasma. We also estimate how the thermal conductivity would be affected by efficient turbulent resistivity.Comment: Major revision: higher resolution simulations lead to significantly different conclusions. 26 pages, 10 figure

    Effect of Pacifier Design on Nonnutritive Suck Maturation and Weight Gain in Preterm Infants: A Pilot Study

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    Background: Pacifiers are effective in promoting oral feeding by increasing the maturation of nonnutritive sucking to nutritive suck in preterm neonates. It is unclear whether pacifier design can influence suck dynamics and weight loss during the first week of life. Objectives: This pilot study examined the feasibility of studying the effect of pacifier design on suck maturation and weight loss in preterm neonates. Methods: Twenty-five preterm neonates (mean [SD] birth weight 1791 [344.9] grams, mean [SD] gestational age 33.1 [1.2] weeks) were studied in a single newborn intensive care unit. Neonates were assigned to either an orthodontic pacifier (n = 13) or a bulb-shaped pacifier (n = 12) immediately after birth. Suck dynamics (cycles per minute, total compressions per minute, cycle bursts, and amplitude) were assessed with an NTrainer (Innara Health, Olathe, Kansas). Weight was recorded during the first week of life on day 1.2 ( ±2.5 days) and day 6.0 ( ±2.1 days). Descriptive statistics were applied to analyze data. Results: No significant differences were seen between groups with respect to birth weight and gestational age. Reproducible nonnutritive sucking measurements could be obtained with the NTrainer, with both types of pacifiers. No differences were detected in nonnutritive sucking dynamics or weight loss over time within each group or between groups. Conclusions: Data indicate that it is feasible to measure nonnutritive sucking dynamics and associated weight loss in relation to pacifier design in preterm neonates. Larger trials over longer time periods are needed to determine whether pacifier design influences suck dynamics and maturation, oromotor function, feeding/weight loss, and dental formation in preterm neonates. ( Curr Ther Res Clin Exp. 2020; 81:XXX–XXX

    Attitudes, Beliefs, and Perceptions on Cannabis Among Older Adults Aged 65 and Older: A cross-sectional Survey.

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    OBJECTIVE: With the rise of medical and recreational cannabis use among older adults, concerns about the potential risks and benefits of cannabis use are increasing. This pilot study aimed to determine the attitudes, beliefs, and perceptions of older adults toward cannabis as a medicinal product, to establish a foundation for future research on how healthcare providers communicate with this population regarding cannabis. METHODS: A cross-sectional survey was conducted on adults aged 65 and older living in Philadelphia. The survey included questions related to participants\u27 demographics, knowledge, attitudes, beliefs, and perceptions of cannabis. Participants were recruited via flyer distributions, publications in newsletters, and a local newspaper. Surveys were conducted from December 2019 through May 2020. Quantitative data were presented using counts, mean, median, and percentages, and qualitative data were analyzed by categorizing common responses. RESULTS: The study aimed to recruit 50 participants, of whom 47 met the requirements, and had their data analyzed, resulting in an average age of 71 years. The majority of participants were male (53%) and Black (64%). Seventy-six percent of participants considered cannabis a highly important treatment for older adults, and 42% considered themselves highly knowledgeable about cannabis. Over half of the participants reported being asked about tobacco (55%) or alcohol (57%) use by their PCP compared to 23% being asked about cannabis. Participants indicated that they most commonly turned to the internet and social media for information about cannabis, while only a small number mentioned relying on their primary care physician (PCP) for such information. DISCUSSION: The results of this pilot study highlight the need for accurate and reliable information about cannabis for older adults and their healthcare providers. As the use of cannabis as a therapy continues to rise, it is crucial for healthcare providers to address misconceptions and encourage older adults to seek out evidence-based research. Further research is needed to explore healthcare providers\u27 perceptions of cannabis therapy and how they can better educate older adults
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