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21.
Andrea Cote Ryan M. Wallace David A. Jackson Maria A. Said Karl Musgrave Cuc H. Tran Clayton Van Houten Alexia Harrist Danielle Buttke Ashley Busacker Veronica Pickens Sarah Anne J. Guagliardo 《Zoonoses and public health》2019,66(5):504-511
Mass bat exposures (MBEs) occur when multiple people are exposed to a bat or a bat colony, often over an extended period. In August 2017, a public health investigation was started in response to an MBE that occurred during May–August 2017 at a national park research station in Wyoming. We identified 176 people who had slept primarily in two lodges (Lodges A and B) at the research station, and successfully contacted 165 (93.8%) of these individuals. Risk assessments (RAs) were administered to all 165 individuals to determine degree and type of exposures to bats (e.g., biting or scratching). Exposure status for research station guests was classified as “non‐exposed,” “low risk” or “high risk,” and counselling was provided to guide post‐exposure prophylaxis (PEP) recommendations. Prior to public health notification and intervention, 19 persons made the decision to pursue PEP. The healthcare‐seeking behaviours of this group were taken to represent outcomes in the absence of public health intervention. (These persons received a RA, and their risk classification was retrospectively assigned.) Approximately 1–2 weeks after conducting the RAs, we conducted a follow‐up survey to determine whether recommendations regarding PEP were ultimately followed. The proportion of individuals that unnecessarily pursued PEP was higher among the 19 individuals that sought health care prior to receiving the RA (p < 0.00001). Among those receiving the RA first, all persons classified as high risk followed public health guidance to seek PEP treatment. Despite this, upon re‐interview, only 21/79 (26.6%) of guests could accurately recall their risk classification, with most people (55.7%) overestimating their risk. Study findings demonstrate that early public health interventions such as RAs can reduce unnecessary use of PEP and that messaging used during rabies counselling should be clear. 相似文献
22.
Jurgenne H Primavera Joseph B Binas Giselle P B Samonte‐Tan Ma Junemie J Lebata Veronica R Alava Mark Walton Lewis LeVay 《Aquaculture Research》2010,41(8):1211-1220
Brackishwater pond culture has been a major factor in mangrove loss in Southeast Asia, hence, the need to develop environment‐friendly technologies such as mud crab Scylla (Portunidae) culture in mangrove pens exists. This study evaluated the effects of mud crab netpen systems in central Philippines on mangrove macroflora, and the replacement of dietary fish with low‐cost pellets. Wild or hatchery‐sourced Scylla olivacea and Scylla serrata were stocked at 0.5–0.8 m−2 in 167–200 m2 nylon netpens (2.3 cm stretched mesh) in Avicennia‐dominated mangrove habitats. The feeding treatments were: (A) Zarraga: (1) no feeding (natural productivity), (2) no feeding for 1 month+supplementary feeding, (3) fish biomass and (4) low‐cost pellets, and (B) Batan: (1) fish biomass and (2) pellets+fish biomass. Feeds were given ad libitum twice daily. Growth and survival rates of S. olivacea in Zarraga pens were not significantly different among treatments, although crabs fed fish biomass had the highest survival, body weight and production. Similarly, growth and survival of S. serrata were not significantly different between the Batan treatments. Economic analysis of the latter gave a 38.5% return on investment (ROI) and 2.6 years payback period (PP) for pellets+fish biomass treatment compared with 27.5% ROI and 3.6 years PP for fish alone. Sensitivity analysis showed an improved economic performance of the pellets+fish biomass treatment by increasing the survival rate. Evaluation of mangrove community structure showed that crab culture reduced species diversity, numbers and biomass of seedlings and saplings, but not of mangrove trees. Therefore, mud crab pen culture is recommended for mangrove sites with mature trees, but not seedlings and saplings, and low‐cost pellets can reduce dependence on fish biomass. 相似文献
23.
A Spatio-Temporal Downscaler for Output From Numerical Models 总被引:2,自引:0,他引:2
Veronica J. Berrocal Alan E. Gelfand David M. Holland 《Journal of Agricultural, Biological & Environmental Statistics》2010,15(2):176-197
Often, in environmental data collection, data arise from two sources: numerical models and monitoring networks. The first
source provides predictions at the level of grid cells, while the second source gives measurements at points. The first is
characterized by full spatial coverage of the region of interest, high temporal resolution, no missing data but consequential
calibration concerns. The second tends to be sparsely collected in space with coarser temporal resolution, often with missing
data but, where recorded, provides, essentially, the true value. Accommodating the spatial misalignment between the two types
of data is of fundamental importance for both improved predictions of exposure as well as for evaluation and calibration of
the numerical model. In this article we propose a simple, fully model-based strategy to downscale the output from numerical
models to point level. The static spatial model, specified within a Bayesian framework, regresses the observed data on the
numerical model output using spatially-varying coefficients which are specified through a correlated spatial Gaussian process. 相似文献
24.
Kondo S Hoar BR Villanueva V Mandrell RE Atwill ER 《American journal of veterinary research》2010,71(11):1339-1347
25.
Dryland cropping systems influence the microbial biomass and enzyme activities in a semiarid sandy soil 总被引:2,自引:0,他引:2
Veronica Acosta-Mart��nez Robert Lascano Francisco Calder��n Jill D. Booker Ted M. Zobeck Dan R. Upchurch 《Biology and Fertility of Soils》2011,47(6):655-667
Indicators of soil quality, such as microbial biomass C and N (MBC, MBN) and enzyme activities (EAs), involved in C, P, N, and S cycling, as affected by dryland cropping systems under conventional (ct) and no tillage (nt) practices were evaluated for 5?years. The soil is sandy loam with an average of 16.4% clay, 67.6% sand, and 0.65?g kg?1 OM at 0?C10?cm. The crops evaluated were rotations of grain sorghum (Sorghum bicolor L.) or forage sorghum (also called haygrazer), cotton (Gossypium hirsutum), and winter rye (Secale cereale): grain sorghum?Ccotton (Srg?CCt), cotton?Cwinter rye?Csorghum (Ct?CRye?CSrg), and forage sorghum?Cwinter rye (Srf?CRye). The tillage treatments did not affect soil MB and EAs of C cycling (i.e., ??-glucosidase, ??-glucosaminidase, ??-galactosidase), P cycling (alkaline phosphatase, phosphodiesterase), and S cycling (arylsulfatase)??except for separation due to tillage for Srf?CRye and Ct?CRye?CSrg observed in PCA plots when all EAs were evaluated together. After 3?years, rotations with a winter cover crop history (Ct?CRye?CSrg and Srf?CRye) enhanced soil MBN (up to 63%) and EAs (21-37%) compared to Srg?CCt. After 5?years, Srg?CCt and Ct?CRye?CSrg showed similar soil MBC, MBN, EAs, total carbon (TC), and organic carbon (OC). A comparison of Srg?CCt plots with nearby continuous cotton (Ct?CCt) research plots in the same soil revealed that it took 5?years to detect higher TC (12%), MBC (38%), and EAs (32?C36%, depending on the enzyme) under Srg?CCt. The significant improvements in MB and EAs found, as affected by dryland cropping systems with a history of winter cover crops and/or higher biomass return crops than cotton, can represent changes in soil OM, nutrient cycling, and C sequestration for sandy soils in the semiarid Texas High Plains region. It is significant that these soil changes occurred despite summer crop failure (2003 and 2006) and lack of winter cover crops (2006) due to lack of precipitation in certain years. 相似文献
26.
A simple direct method is described to measure the length of fungal hyphae in soil. The accuracy of the method is discussed and comparison is made with other methods recommended for assaying fungal biomass in soil. Some results showing the seasonal fluctuation of mycelial length in soil are presented. 相似文献
27.
28.
Milan Milovancev Joanne L. Tuohy Katy L. Townsend Veronica L. Irvin 《Veterinary and comparative oncology》2019,17(3):354-364
The present peer‐reviewed veterinary literature contains conflicting information regarding the impact of surgical margin completeness on risk of local tumour recurrence in canine soft tissue sarcoma (STS). This systematic review and meta‐analysis was designed to answer the clinical question: “Does obtaining microscopically tumour‐free surgical margins reduce risk for local tumour recurrence in canine cutaneous and subcutaneous STS?” A total of 486 citations were screened, 66 of which underwent full‐text evaluation, with 10 studies representing 278 STS excisions ultimately included. Cumulatively, 16/164 (9.8%) of completely excised and 38/114 (33.3%) of incompletely excised STS recurred. Overall relative risk of 0.396 (95% confidence interval = 0.248‐0.632) was calculated for local recurrence in STS excised with complete margins as compared to STS excised with incomplete margins. Risk of bias was judged to be low for all studies in terms of selection bias and detection bias but high for all studies in terms of performance bias and exclusion bias. The results of the present meta‐analysis, coupled with the results of individual previous studies, strongly suggest that microscopically complete surgical margins confer a significantly reduced risk for local tumour recurrence in canine STS. Future studies ideally should adhere to standardized conducting and reporting guidelines to reduce systematic bias. 相似文献
29.
Karin U. Sorenmo Amy C. Durham Veronica Kristiansen Laura Pena Michael H. Goldschmidt Darko Stefanovski 《Veterinary and comparative oncology》2019,17(4):479-488
Canine mammary carcinomas (CMC) represent a range of histolopathological subtypes with diverse biological behaviours. Several individual factors, including stage, grade, subtypes and presence of invasion, predict outcome. Less is known how these factors interact and impact prognosis. The purpose of this work was to develop and test comprehensive bio‐scoring systems in CMCs. Clinical and histopathological data from 127 dogs with MCs treated through two prospective studies were obtained. All dogs underwent standardized pre‐surgical staging, treatments and regular follow‐up visits. All tumours were evaluated, classified and graded according to published guidelines. Time to primary metastasis was the main endpoint in this study. Two bio‐scoring systems were developed: The multivariate scoring (MVS) was based on traditional statistical analysis where only factors significant in the multivariate analysis (tumour size and grade) were kept for the final model. The refined flexible scoring (RFS) system was based on results from subgroup analysis, which guided the development of a flexible system. Progressive worsening prognosis was observed with increasing bio‐scores in both systems. MVS: Median primary metastasis‐free survival (TTM1 days) was not reached in dogs with bio‐scores 0 to 5, 10, 15 and 648, 149, 317, in MVS groups 25, 30, 40, respectively. Similarly, TTM1 was not reached in dogs with RFS 0, 1, 2 and 374, 407 and 149, in dogs with bio‐scores 3, 4, 5, respectively. However, a more distinct separation between dogs with high risk vs low risk for metastasis was observed with RFS, suggesting superior overall prognostication regarding the risk for metastasis. 相似文献
30.