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41.
42.
Tom Lindstr?m Daniel A. Grear Michael Buhnerkempe Colleen T. Webb Ryan S. Miller Katie Portacci Uno Wennergren 《PloS one》2013,8(1)
Networks are rarely completely observed and prediction of unobserved edges is an important problem, especially in disease spread modeling where networks are used to represent the pattern of contacts. We focus on a partially observed cattle movement network in the U.S. and present a method for scaling up to a full network based on Bayesian inference, with the aim of informing epidemic disease spread models in the United States. The observed network is a 10% state stratified sample of Interstate Certificates of Veterinary Inspection that are required for interstate movement; describing approximately 20,000 movements from 47 of the contiguous states, with origins and destinations aggregated at the county level. We address how to scale up the 10% sample and predict unobserved intrastate movements based on observed movement distances. Edge prediction based on a distance kernel is not straightforward because the probability of movement does not always decline monotonically with distance due to underlying industry infrastructure. Hence, we propose a spatially explicit model where the probability of movement depends on distance, number of premises per county and historical imports of animals. Our model performs well in recapturing overall metrics of the observed network at the node level (U.S. counties), including degree centrality and betweenness; and performs better compared to randomized networks. Kernel generated movement networks also recapture observed global network metrics, including network size, transitivity, reciprocity, and assortativity better than randomized networks. In addition, predicted movements are similar to observed when aggregated at the state level (a broader geographic level relevant for policy) and are concentrated around states where key infrastructures, such as feedlots, are common. We conclude that the method generally performs well in predicting both coarse geographical patterns and network structure and is a promising method to generate full networks that incorporate the uncertainty of sampled and unobserved contacts. 相似文献
43.
Introduction
Few have examined determinants of adverse outcomes in patients presenting with ascending cholangitis. The objective of this study was to examine factors associated with in-hospital mortality, prolonged length of stay (LOS) and increased hospital charges (HC) in patients presenting with acute cholangitis.Methods
Within the Health Care Utilization Project Nationwide Inpatient Sample (NIS), we focused on patients, 18 years and older, admitted to the emergency department with cholangitis as primary diagnosis (1998–2009). Models were fitted to predict likelihood of in-hospital mortality, prolonged LOS and increased HC. Covariates included race, day of admission, insurance status, socio-economical status and other patient and hospital characteristics.Results
Overall, weighted estimates of 248,942 patients were admitted with acute cholangitis between 1998 and 2009, of which 13,534 (5.4%) died during the admission. Multivariable analyses revealed that relative to Caucasian patients, African American, Hispanic and Asian and Pacific Islander patients were more likely to die (OR = 1.61, p<0.001, OR = 1.20, p = 0.01 and OR = 1.26, p = 0.008), to experience a prolonged LOS (OR = 1.77, p<0.001, OR = 1.30, p<0.001, 1.34, p<0.001), and to incur high HC (OR = 1.83, p<0.001, OR = 1.51, p<0.001, OR = 1.56, p<0.001). Moreover, Medicaid and Medicare patients were more likely to die (OR = 1.64, p<0.001, OR = 1.24, p<0.001), to experience a prolonged LOS (1.74, p<0.001, OR = 1.25, p<0.001) and to incur high HC (OR = 1.23, p = 0.002, OR = 1.12, p = 0.002) compared to privately insured patients. In subgroup analysis, there were no differences for Medicare patients age 65 years and over. However, those under 65, most of whom have disability or end stage renal disease, were more likely to experience the negative outcomes.Conclusion
Race and insurance status represent independent predictors of in-hospital mortality and adverse outcomes in patients presenting with cholangitis. Whether these disparities are due to biological predisposition or unequal quality of care requires further investigation. Regardless, efforts should be made to reduce these outcome disparities. 相似文献44.
Brian P. Fallon Bryan Curnutte Kevin A. Maupin Katie Partyka Sunguk Choi Randall E. Brand Christopher J. Langmead Waibhav Tembe Brian B. Haab 《PloS one》2013,8(6)
The development of accurate clinical biomarkers has been challenging in part due to the diversity between patients and diseases. One approach to account for the diversity is to use multiple markers to classify patients, based on the concept that each individual marker contributes information from its respective subclass of patients. Here we present a new strategy for developing biomarker panels that accounts for completely distinct patient subclasses. Marker State Space (MSS) defines “marker states” based on all possible patterns of high and low values among a panel of markers. Each marker state is defined as either a case state or a control state, and a sample is classified as case or control based on the state it occupies. MSS was used to define multi-marker panels that were robust in cross validation and training-set/test-set analyses and that yielded similar classification accuracy to several other classification algorithms. A three-marker panel for discriminating pancreatic cancer patients from control subjects revealed subclasses of patients based on distinct marker states. MSS provides a straightforward approach for modeling highly divergent subclasses of patients, which may be adaptable for diverse applications. 相似文献
45.
Katie A. Harris Joseph D. Clark R. Dwayne Elmore Craig A. Harper 《The Journal of wildlife management》2020,84(8):1590-1600
Eastern box turtles (Terrapene carolina carolina) are widely distributed throughout the eastern United States. Although once common throughout much of its distribution, the species has experienced declines in local populations. Understanding resource selection is important for the conservation of this species; however, few data exist on resource selection for eastern box turtles in the southeastern United States. We estimated home range and resource selection for 100 individual turtles in the Blue Ridge, Ridge and Valley, and Cumberland Plateau and Mountains physiographic regions in Tennessee, USA, from 2016 to 2018. We used step-selection functions to investigate eastern box turtle resource selection during May–August 2017 and May–August 2018 at 2 spatial scales. We classified vegetation type, measured vegetation composition and structure, recorded time since fire, and measured coarse woody debris abundance at 1,225 used telemetry locations and 1,225 associated available points. Home range sizes averaged 9.3 ha ± 3.0 (SE) using minimum convex polygon analysis, 8.25 ha ± 2.88 using 95% kernel density analysis, and 1.50 ha ± 0.56 using 50% kernel density analysis. Box turtles selected areas with greater visual obstruction at the 0–0.25-m level, greater amounts of 10-hour and 100-hour fuels (timelag categories used in fire-danger ratings), and greater litter depths compared to available locations. Box turtles were more likely to select areas with greater cover of brambles and coarser woody debris and were less likely to select areas with less vegetation cover. Vegetation type and time since last fire did not affect selection. Our data suggest that management activities that encourage greater understory vegetation cover, greater visual obstruction at the 0–0.25-m level, and greater bramble cover will enhance habitat quality for eastern box turtles. © 2020 The Wildlife Society. 相似文献
46.
Katie Parker Krista Ryall Brian H. Aukema Peter Silk 《Entomologia Experimentalis et Applicata》2020,168(2):166-173
The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a highly destructive primary pest of ash (Fraxinus sp., Oleaceae) trees outside of its native range. Ash is an important component of many ecosystems and its loss would be detrimental to both the economy and the environment. The present study aimed to improve our understanding of the effectiveness of green sticky prism traps baited with host kairomone and insect pheromone lures for A. planipennis and to collect data for modelling the range of attraction of the pheromone (3Z)-dodecen-12-olide [(3Z)-lactone]. Traps were deployed over a single flight season in urban locations of Ontario, Canada, with low densities of EAB. Traps were placed in pairs of trees separated by not more than 25 m. All traps contained the host kairomone, (3Z)-hexenol, with the remaining half in each pairing additionally baited with (3Z)-lactone pheromone. Both lure types were highly effective in capturing EAB, with >90% detection rates overall. However, traps baited with the lactone pheromone and host volatile lures doubled trap captures of EAB over distances of at least 25 m from the nearest traps baited with only host volatiles. Although the baseline detection rate of traps containing (3Z)-hexenol alone is not significantly reduced compared with traps containing (3Z)-lactone, the overall trap effectiveness is significantly increased when (3Z)-lactone is present. The implications for the use of (3Z)-lactone at 3 mg per septum dose in an early warning trapping system are discussed. Trap layout methods and risk-based analysis models can now be further refined by including these data about the attractive range of lures and their behaviour in different plot environments. 相似文献
47.
Katie H. Homeyer Priyadarshini Singha Marcus J. Goudie Hitesh Handa 《Biotechnology and bioengineering》2020,117(7):2237-2246
The chances of ventilator-associated pneumonia (VAP) increases 6–20 folds when an endotracheal tube (ETT) is placed in a patient. VAP is one of the most common hospital-acquired infections and comprises 86% of the nosocomial pneumonia cases. This study introduces the idea of nitric oxide-releasing ETTs (NORel-ETTs) fabricated by the incorporation of the nitric oxide (NO) donor S-nitroso-N-acetylpenicillamine (SNAP) into commercially available ETTs via solvent swelling. The impregnation of SNAP provides NO release over a 7-day period without altering the mechanical properties of the ETT. The NORel-ETTs successfully reduced the bacterial infection from a commonly found pathogen in VAP, Pseudomonas aeruginosa, by 92.72 ± 0.97% when compared with the control ETTs. Overall, this study presents the incorporation of the active release of a bactericidal agent in ETTs as an efficient strategy to prevent the risk of VAP. 相似文献
48.
Sarah Papworth E.J. Milner‐Gulland Katie Slocombe 《American journal of primatology》2013,75(11):1117-1128
Ethnoprimatology is an important and growing discipline, studying the diverse relationships between humans and primates. However there is a danger that too great a focus on primates as important to humans may obscure the importance of other animal groups to local people. The Waorani of Amazonian Ecuador were described by Sponsel [Sponsel (1997) New World Primates: Ecology, evolution and behavior. New York: Aldine de Gruyter. p 143–165] as the “natural place” for ethnoprimatology, because of their close relationship to primates, including primates forming a substantial part of their diet. Therefore they are an ideal group in which to examine contemporary perceptions of primates in comparison to other types of animal. We examine how Waorani living in Yasuní National Park name and categorize primates and other common mammals. Although there is some evidence that the Waorani consider primates a unique group, the non‐primate kinkajou and olingo are also included as part of the group “monkeys,” and no evidence was found that primates were more important than other mammals to Waorani culture. Instead, a small number of key species, in particular the woolly monkey (Lagothrix poeppigii) and white‐lipped peccary (Tayassu pecari), were found to be both important in the diet and highly culturally salient. These results have implications for both ethnoprimatologists and those working with local communities towards broader conservation goals. Firstly, researchers should ensure that they and local communities are referring to the same animals when they use broad terms such as “monkey,” and secondly the results caution ethnoprimatologists against imposing western taxonomic groups on indigenous peoples, rather than allowing them to define themselves which species are important. Am. J. Primatol. 75:1117–1128, 2013. © 2013 The Authors. American Journal of Primatology Published by Wiley Periodicals, Inc. 相似文献
49.
Katie E. Olson Pranesh Narayanaswami Pamela D. Vise David F. Lowry Marc S. Wold Gary W. Daughdrill 《Journal of biomolecular structure & dynamics》2013,31(2):113-124
Abstract The transient secondary structure and dynamics of an intrinsically unstructured linker domain from the 70 kDa subunit of human replication protein A was investigated using solution state NMR. Stable secondary structure, inferred from large secondary chemical shifts, was observed for a segment of the intrinsically unstructured linker domain when it is attached to an N-terminal protein interaction domain. Results from NMR relaxation experiments showed the rotational diffusion for this segment of the intrinsically unstructured linker domain to be correlated with the N-terminal protein interaction domain. When the N-terminal domain is removed, the stable secondary structure is lost and faster rotational diffusion is observed. The large secondary chemical shifts were used to calculate phi and psidihedral angles and these dihedral angles were used to build a backbone structural model. Restrained molecular dynamics were performed on this new structure using the chemical shift based dihedral angles and a single NOE distance as restraints. In the resulting family of structures a large, solvent exposed loop was observed for the segment of the intrinsically unstructured linker domain that had large secondary chemical shifts. 相似文献
50.