Emulation Engines: Choice and Quantification of Uncertainty for Complex Hydrological Models     

Daniel W. Gladish  Daniel E. Pagendam  Luk J. M. Peeters  Petra M. Kuhnert  Jai Vaze 《Journal of Agricultural, Biological & Environmental Statistics》2018,23(1):39-62

Complex, mechanistic hydrological models can be computationally expensive, have large numbers of input parameters, and generate multivariate output. Model emulators can be constructed to approximate these complex models with substantial computational savings, making activities such as sensitivity analysis, calibration and uncertainty analysis feasible. Success in the use of an emulator relies on it making accurate and precise predictions of the model output. However, it is often unclear what type of emulation approach will be suitable. We present a comparison of reduced-rank, multivariate emulators built upon different ‘emulation engines’ and apply them to the Australian Water Resource Assessment System model. We examine first-order and second-order approaches which focus on specifying the mean and covariance, respectively. We also introduce a nonparametric approach for quantifying the uncertainty associated with the emulated prediction where this has bounded support. Our results demonstrate that emulation engines based on second-order approaches, such as Gaussian processes, can be computationally burdensome and may be comparable in performance to computationally efficient, first-order methods such as random forests.Supplementary materials accompanying this paper appear online.  相似文献   

Clinical Use of Deslorelin for the Control of Reproduction in the Bitch     

S Romagnoli  C Stelletta  C Milani  D Gelli  ME Falomo  A Mollo 《Reproduction in domestic animals》2009,44(S2):36-39

This study was conducted to evaluate clinical efficacy of deslorelin for inhibiting reproduction in the bitch. Ten adult healthy bitches or bitches with mammary neoplasia for which owners were requesting suppression of cyclicity without performing gonadectomy were administered a 4.7- or a 9.4-mg deslorelin implant subcutaneously. The first implant of deslorelin was administered in anoestrus (n = 5) or in dioestrus (n = 5). Treatment was repeated every 5 months for as long as necessary based on the clinical situation of the dog and owner's desires. Some of the bitches implanted in anoestrus came in heat within 4–15 days after treatment, while none of the bitches implanted in dioestrus showed heat during treatment. Suppression of reproductive cyclicity was successfully achieved in 6/10 bitches for 1–4 years. No behavioural and local/general side-effects were observed in any of the treated bitches. The 4.7-mg deslorelin implant may work well for suppression of cyclicity provided that it is administered in dioestrus and at intervals of 4.5 months. A 9.4-mg implant may be more suitable for this use although its efficacy may also be shorter than 12 months. Owner compliance is an important limiting factor.  相似文献   

CAN SONOGRAPHIC FINDINGS PREDICT THE RESULTS OF LIVER ASPIRATES IN DOGS WITH SUSPECTED LIVER DISEASE?     

MARTIN GUILLOT  MARC-ANDRÉ D'ANJOU  KATE ALEXANDER  CHRISTIAN BÉDARD  MICHEL DESNOYERS  GUY BEAUREGARD  JÉRÔME R. E. DEL CASTILLO 《Veterinary radiology & ultrasound》2009,50(5):513-518

While abdominal ultrasound and ultrasound-guided fine-needle aspiration cytology are often combined to help determine the type of liver disease in dogs, little is known about the relationship that may exist between the results of these tests. We hypothesized that specific sonographic findings, or combinations of findings, may predict results of liver ultrasound-guided fine-needle aspiration cytology. Hepatic and extrahepatic sonographic findings were recorded prospectively using a standardized form in 70 dogs with clinically suspected liver disease and in which liver ultrasound-guided fine-needle aspiration cytology was performed. The predictive value of sonographic findings in regard to the category of cytology results was assessed with stepwise logistic regression analysis. Sonographic detection of a hepatic mass (≥3 cm; risk ratio [RR] 3.83, 95% Wald confidence intervals [95% CI] 2.42–3.93, P =0.0036), ascites (RR 3.82, 95% CI 1.94–4.28, P =0.0044), abnormal hepatic lymph node(s) (RR 3.01, 95% CI 1.22–4.88, P =0.0262), and abnormal spleen (RR 3.26, 95% CI 1.20–3.85, P =0.0274) were the most predictive of liver neoplasia on cytology. Conversely, sonographic detection of hepatic nodules (<3 cm; RR 1.97, 95% CI 0.95–2.96, P =0.0666) was most predictive of vacuolar hepatopathy on cytology. In dogs with suspected liver disease, several sonographic findings, alone or combined, are thus predictive of liver ultrasound-guided fine-needle aspiration cytology results. In the light of the fact that ultrasound-guided fine-needle aspiration cytology of the liver has limitations, these predictabilities could influence the selection of diagnostic tests to reach a reliable diagnosis.  相似文献   

成都平原不同耕作模式的农田效应研究—— II.土壤综合质量评价   总被引：1，自引：0，他引：1  

梁淑敏  谢瑞芝  李朝苏  杨锦忠  汤永禄  吴春  王灵便  李少昆 《中国农业科学》2011,44(4):738-744

 【目的】研究成都平原不同耕作模式对土壤质量性状的影响,探索建立适合当地生产条件的土壤质量评价体系,筛选出适宜该地的耕作模式,为提高当地土壤生产力水平、改善土壤质量提供借鉴。【方法】通过长期定位试验获取不同耕作模式对土壤性状及作物生产指标的影响效应,采用主成分分析的方法筛选评价指标,运用因子分析法对土壤质量进行综合评价。【结果】筛选出的评价土壤综合质量的指标在不同土壤层次存在明显差别：0—10 cm土层的主要影响因子为毛管孔隙度、土壤比重、土壤饱和渗水速率、土壤紧实度、土壤有机质;10—20 cm土层的主要影响因子为总孔隙度、非毛管孔隙度、饱和渗水速率、土壤吸湿水、土壤紧实度;0—20 cm土层的主要影响因子为非毛管孔隙度、土壤比重、土壤饱和渗水速率、土壤紧实度。其中,不同土层的共同影响因子——土壤饱和渗水速率和土壤紧实度是目前当地土壤质量的限制因子。土壤质量综合评价结果表明0—10 cm土层以麦稻双免耕作模式最好,10—20 cm土层麦免+稻旋最好,0—20 cm土层麦免+稻旋最好。【结论】在本研究的试验条件和当地实际情况下,对成都平原土壤质量具有良好效益的耕作模式为麦免+稻旋模式。  相似文献   

黔北地区主要竹种竹材气干密度与力学性质的关系研究     

王健  司徒春南  杜文军  谢双喜 《广东农业科学》2011,38(5):194-196

对黔北地区几种主要竹种的气干密度与力学性质的关系研究表明:各竹种的气千密度与力学性质除部分竹种外均存在一定的曲线或直线关系,其中在气干密度与抗剪强度关系中,除慈竹、花吊丝、毛脚龙竹、金佛山方竹等竹种外,其他竹种均可利用回归方程T12=ap12b,T12=ap12+b进行估测.在气干密度与顺纹抗拉强度关系中除硬头黄、花吊...  相似文献   

An international terminology for grazing lands and grazing animals     

V.G. Allen  C. Batello  E.J. Berretta  J. Hodgson  M. Kothmann  X. Li  J. McIvor  J. Milne  C. Morris  A. Peeters  M. Sanderson  The Forage  Grazing Terminology Committee 《Grass and Forage Science》2011,66(1):2-28

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Glucocorticoid‐deficient hypoadrenocorticism secondary to intravascular lymphoma in the adrenal glands of a dog          下载免费PDF全文

ME Buckley  PS Chapman  A Walsh 《Australian veterinary journal》2017,95(3):64-67

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Emesis in dogs: a review     

C. Elwood  P. Devauchelle  J. Elliott  V. Freiche  A. J. German  M. Gualtieri  E. Hall  E. den Hertog  R. Neiger  D. Peeters  X. Roura  K. Savary-Bataille 《The Journal of small animal practice》2010,51(1):4-22

Emesis is a common presenting sign in small animal practice. It requires a rational approach to management that is based upon a sound understanding of pathophysiology combined with logical decision making. This review, which assesses the weight of available evidence, outlines the physiology of the vomiting reflex, causes of emesis, the consequences of emesis and the approach to clinical management of the vomiting dog. The applicability of diagnostic testing modalities and the merit of traditional approaches to management, such as dietary changes, are discussed. The role and usefulness of both traditional and novel anti-emetic drugs is examined, including in specific circumstances such as following cytotoxic drug treatment. The review also examines areas in which common clinical practice is not necessarily supported by objective evidence and, as such, highlights questions worthy of further clinical research.  相似文献   

Serum and bronchoalveolar lavage fluid endothelin-1 concentrations as diagnostic biomarkers of canine idiopathic pulmonary fibrosis     

Krafft E  Heikkilä HP  Jespers P  Peeters D  Day MJ  Rajamäki MM  Mc Entee K  Clercx C 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(5):990-996

Background: Diagnosis of canine idiopathic pulmonary fibrosis (IPF) is challenging. Endothelin‐1 (ET1) is a biomarker of IPF in humans, but whether ET1 can detect and differentiate IPF from other canine respiratory diseases is unknown. Objective: To evaluate whether measurement of the concentration of ET1 in serum and bronchoalveolar lavage fluid (BALF) can be used to distinguish canine IPF from chronic bronchitis (CB) and eosinophilic bronchopneumopathy (EBP). Animals: Twelve dogs with IPF, 10 dogs with CB, 6 dogs with EBP, 13 privately owned healthy West Highland White Terriers (WHWT), and 9 healthy Beagle dogs. Methods: Prospective, case control study. ET1 concentration was determined by ELISA in serum and in BALF. Results: No significant difference in serum ET1 concentration was detected between healthy Beagle dogs and WHWT. Serum ET1 concentration was higher in dogs with IPF (median interquartile range; 2.32 pg/mL, 2.05–3.38) than healthy Beagle dogs (1.28, 1.07–1.53; P < .001), healthy WHWT (1.56, 1.25–1.85; P < .001), dogs with EBP (0.94 0.68–1.01; P = .001), and dogs with CB (1.54 0.74–1.82; P = .005). BALF ET1 concentration was below the detection limit in healthy WHWT and in dogs with CB, whereas it was measurable in all dogs with IPF. A cut‐off serum concentration of 1.8 pg/mL had a sensitivity of 100% and a specificity of 81.2% for detection of IPF, with an area under the receiver operating characteristic curve of 0.818. Conclusions and Clinical Importance: Serum ET1 can differentiate dogs with IPF from dogs with EBP or CB. ET1 can be detected in BALF of dogs with IPF.  相似文献   

Identification and localization of the structural proteins of anguillid herpesvirus 1     

van Beurden SJ  Leroy B  Wattiez R  Haenen OL  Boeren S  Vervoort JJ  Peeters BP  Rottier PJ  Engelsma MY  Vanderplasschen AF 《Veterinary research》2011,42(1):105

ABSTRACT: Many of the known fish herpesviruses have important aquaculture species as their natural host, and may cause serious disease and mortality. Anguillid herpesvirus 1 (AngHV-1) causes a hemorrhagic disease in European eel, Anguilla anguilla. Despite their importance, fundamental molecular knowledge on fish herpesviruses is still limited. In this study we describe the identification and localization of the structural proteins of AngHV-1. Purified virions were fractionated into a capsid-tegument and an envelope fraction, and premature capsids were isolated from infected cells. Proteins were extracted by different methods and identified by mass spectrometry. A total of 40 structural proteins were identified, of which 7 could be assigned to the capsid, 11 to the envelope, and 22 to the tegument. The identification and localization of these proteins allowed functional predictions. Our findings include the identification of the putative capsid triplex protein 1, the predominant tegument protein, and the major antigenic envelope proteins. Eighteen of the 40 AngHV-1 structural proteins had sequence homologues in related Cyprinid herpesvirus 3 (CyHV-3). Conservation of fish herpesvirus structural genes seemed to be high for the capsid proteins, limited for the tegument proteins, and low for the envelope proteins. The identification and localization of the structural proteins of AngHV-1 in this study adds to the fundamental knowledge of members of the Alloherpesviridae family, especially of the Cyprinivirus genus.  相似文献