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211.
Background Cardiovascular disease is the primary cause of morbidity and mortality among captive chimpanzees. But there are no clinical definitions of normotension or hypertension in chimpanzees. Methods We analyzed 1 year of blood pressure (BP) data from a population of 261 healthy captive adult chimpanzees using a consistent set of criteria to ascertain health. Results Systolic BP varied by body weight. Diastolic BP varied by age. Median normotension was 126/63 mmHg, with an upper limit of 147/84 mmHg. We defined categories of pre‐hypertension (148/85—153/88 mmHg) and hypertension (≥154/89 mmHg). The prevalence of elevated BP was 15%. The relative risk of mortality was 2.60, compared to normotensive animals. Conclusions We used contemporary methods from human laboratory medicine to define reliable reference intervals for chimpanzee BP. Results allow accurate diagnosis of hypertension and pre‐hypertension, and demonstrate an effect of elevated BP on mortality. 相似文献
212.
The protein lysate array is an emerging technology for quantifying the protein concentration ratios in multiple biological samples. Statistical inference for a parametric quantification procedure has been inadequately addressed in the literature, mainly because the appropriate asymptotic theory involves a problem with the number of parameters increasing with the number of observations. In this article, we develop a multistep procedure for the Sigmoidal models, ensuring consistent estimation of the concentration levels with full asymptotic efficiency. The results obtained in the article justify inferential procedures based on large sample approximations. Simulation studies and real data analysis are used in the article to illustrate the performance of the proposed method in finite samples. The multistep procedure is convenient to work with asymptotically, and is recommended for its statistical efficiency in protein concentration estimation and improved numerical stability by focusing on optimization of lower-dimensional objective functions. 相似文献
213.
Cameras have been used throughout the world to estimate wildlife abundance and occupancy. Abundance estimates generated by
camera surveys tend to be less invasive, less costly, and more accurate than other means in certain situations. We sought
to expand and test the effectiveness of camera surveys on sika deer in Maryland. In 2008, we setup surveys with a 7-day pre-bait
period followed by a 7-day active camera survey with 15 cameras. In 2009, we ran the cameras for the entire 14-day survey
and moved cameras after each survey to determine if biases occur when using the same camera sites. During both years and all
surveys, camera density was approximately 1-camera/65-ha. The abundance estimates were similar between years and estimators.
In 2009, increasing photo intervals from 1-min to 5- and 10-min intervals reduced the number of pictures by 66 and 81%, respectively,
while providing similar abundance estimates. We calculated the daily detection probabilities for all identifiable deer and
we used radio-collared males that occurred within 2 km of the survey grid to assist in determining the optimum survey length.
Detection probability did not vary between surveys in the same year, but varied between 2008 and 2009, most likely due to
unlimited bait being available during 2008 surveys. Camera surveys have proven to be an accurate and cost effective means
of estimating wildlife abundance and can be used successfully to determine sika deer abundance. 相似文献
214.
Shinichi Nakagawa Holger Schielzeth 《Biological reviews of the Cambridge Philosophical Society》2010,85(4):935-956
Repeatability (more precisely the common measure of repeatability, the intra‐class correlation coefficient, ICC) is an important index for quantifying the accuracy of measurements and the constancy of phenotypes. It is the proportion of phenotypic variation that can be attributed to between‐subject (or between‐group) variation. As a consequence, the non‐repeatable fraction of phenotypic variation is the sum of measurement error and phenotypic flexibility. There are several ways to estimate repeatability for Gaussian data, but there are no formal agreements on how repeatability should be calculated for non‐Gaussian data (e.g. binary, proportion and count data). In addition to point estimates, appropriate uncertainty estimates (standard errors and confidence intervals) and statistical significance for repeatability estimates are required regardless of the types of data. We review the methods for calculating repeatability and the associated statistics for Gaussian and non‐Gaussian data. For Gaussian data, we present three common approaches for estimating repeatability: correlation‐based, analysis of variance (ANOVA)‐based and linear mixed‐effects model (LMM)‐based methods, while for non‐Gaussian data, we focus on generalised linear mixed‐effects models (GLMM) that allow the estimation of repeatability on the original and on the underlying latent scale. We also address a number of methods for calculating standard errors, confidence intervals and statistical significance; the most accurate and recommended methods are parametric bootstrapping, randomisation tests and Bayesian approaches. We advocate the use of LMM‐ and GLMM‐based approaches mainly because of the ease with which confounding variables can be controlled for. Furthermore, we compare two types of repeatability (ordinary repeatability and extrapolated repeatability) in relation to narrow‐sense heritability. This review serves as a collection of guidelines and recommendations for biologists to calculate repeatability and heritability from both Gaussian and non‐Gaussian data. 相似文献
215.
Background
Chinese Tibetans have a series of distinctive physiological traits which enable them to tolerate the extreme environment of the Tibetan plateau. P-selectin gene has been proved to be highly polymorphic in Europeans and Americans. Nevertheless, studies on either the frequency distributions of single nucleotide polymorphisms (SNPs) or haplotype diversity and linkage disequilibrium of P-selectin gene in Chinese Tibetan population are still unavailable.Methods
The frequency distributions of 3 SNPs in P-selectin gene promoter (− 2123C/G, − 1969A/G, − 1817T/C) and 3 SNPs in exon region (Ser290Asn, Val599Leu, Thr715Pro) were investigated by real-time PCR and high-resolution melting method among 314 Chinese Tibetans and 328 age- and sex-matched Han people.Results
The frequencies of the − 2123G and − 1817T alleles among the Tibetan population had no significant differences from those of the Han population. Among the Tibetan population, the G allele frequency of − 1969A/G and Ser290Asn were both higher than those of the Han population. Val599Leu and Thr715Pro did not show any polymorphism in the two populations. In the Tibetan population, − 2123C/G, − 1969A/G, − 1817T/C and Ser290Asn were in tight linkage disequilibrium with each other.Conclusions
The frequency distributions of − 1969A/G and Ser290Asn polymorphisms in the Tibetan population were different from those in the Han population. 相似文献216.
Samuel Woldemariam Sahile Zewdu Teshome Mulugeta Kibret 《Archives Of Phytopathology And Plant Protection》2013,46(9-10):461-484
AbstractIntegrated management of faba bean chocolate spot (Botrytis fabae Sard.) was studied using moderately tolerant variety, “Hachalu” and the local cultivar at Chilga district during 2016 main cropping season. The objective was to evaluate effect of host resistance, intercropping and fungicide applications on epidemics of faba bean chocolate spot, yield and yield components of faba bean, and sole and intercrop systems productivity. The experiment was randomised complete block design in a factorial combination of two faba bean cultivars, two cropping systems (Hachalu- and local-barley intercropping in 2:1 ratio) and four levels of fungicide (Chlorothalonil) spray and integration in three replications of faba bean and barley, respectively. Cultivars and spray intervals significantly (p?<?.01) affected the seed yield while cultivars alone had significant variation (p?<?.01) on 100-seed weight as a main effect. Therefore, 21-days fungicide spray intervals integrated with Hachalu sole and Hachalu-barley intercropping may be considered for chocolate spot management. 相似文献
217.
Razaw Al‐Sarraj Claudia von Brmssen Johannes Forkman 《Biometrical journal. Biometrische Zeitschrift》2019,61(5):1242-1257
This article derives generalized prediction intervals for random effects in linear random‐effects models. For balanced and unbalanced data in two‐way layouts, models are considered with and without interaction. Coverage of the proposed generalized prediction intervals was estimated in a simulation study based on an agricultural field experiment. Generalized prediction intervals were compared with prediction intervals based on the restricted maximum likelihood (REML) procedure and the approximate methods of Satterthwaite and Kenward and Roger. The simulation study showed that coverage of generalized prediction intervals was closer to the nominal level 0.95 than coverage of prediction intervals based on the REML procedure. 相似文献
218.
Marker-assisted recurrent selection for cumulating additive and interactive QTLs in recombinant inbred lines 总被引:7,自引:0,他引:7
G. Charmet N. Robert M. R. Perretant G. Gay P. Sourdille C. Groos S. Bernard M. Bernard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(7-8):1143-1148
A computer program has been designed to manage marker information in recombinant inbred-line populations. The objective is
to select pairs of inbred lines (either recombinant-inbred or doubled-haploid) to be intercrossed, in order to accumulate
all or most favourable alleles, either with additive effects or with interactive effects. The population size required to
have a 95% chance of obtaining the best line from a given cross is computed, taking into account the number of QTLs and the
probability that no recombination event occurs in any of the QTL confidence intervals. It is shown that the accuracy of QTL
location greatly affects selection efficiency and that a recurrent selection scheme is highly preferable for pyramiding many
QTLs. An application to the bread-making quality improvement of wheat is presented.
Received: 25 September 1998 / Accepted: 29 July 1999 相似文献
219.
Paul Somerville Tetsuhisa Miwa Wei Liu Anthony Hayter 《Biometrical journal. Biometrische Zeitschrift》2001,43(5):533-542
Lee and Spurrier (1995) present one‐sided and two‐sided confidence interval procedures for making successive comparisons between ordered treatments. Their procedures have important applications for problems where the treatments can be assumed to satisfy a simple ordering, such as for a sequence of increasing dose‐levels of a drug. The two‐sided procedure provides both upper and lower bounds on the differences between successive treatments, whereas the one‐sided procedure only provides lower bounds on these differences. However, the one‐sided procedure allows sharper inferences regarding which treatments can be declared to be better than their previous ones. In this paper we apply the results obtained in Hayter , Miwa , and Liu (2000) to develop a new procedure which combines the good aspects of both the one‐sided and the two‐sided procedures. This new procedure maintains the inferential sensitivity of the one‐sided procedure while also providing both upper and lower bounds on the differences between successive treatments. Some new critical points are needed which are tabulated for the balanced case where the sample sizes are all equal. The application of the new procedure is illustrated with an example. 相似文献
220.
Bt与EoNPV混用配比优劣性图谱分析 总被引:2,自引:0,他引:2
苏云金杆菌(Bt)和茶尺蠖核型多角体病毒(EoNPV)等,两类生物源杀虫剂常以复配混用方式应用.由于药效的迟缓,而明显表现出剂量-时间-致死作用复合特征.但目前尚缺乏与之相适应的混用配比优劣判别标准.受叶庆华等地学信息图谱分析和曹进等指纹图谱整体相似性分析理论和方法的启发,用室内人工饲养繁殖茶尺蠖2龄初—中期幼虫生物测定结果作为基础数据,分析研究了Bt与EoNPV混用的剂量-时间-致死作用复合特征,并进行了配比优劣性判别的尝试.首先将生物测定的有关结果输入SPSS统计分析软件包和Excel绘图软件,进行多因素方差分析,同时分别绘出不同药剂处理的,以剂量梯度为横轴,以累加死亡虫数为纵轴的不同观察时段害虫致死过程的曲线组图,简称时段药效信息图;再使用SPSS软件包进行单因素方差分析,提取出用于整体相似性比较的图谱单元Ⅰ和用于细节非相似性比较的图谱单元Ⅱ,且分别量化,由此得到相似值和非相似值,据此又分别算得相似系数和非相似系数;最后综合成一种混用配比优劣性总体判别指标,简称Q值.结果,Bt:EoNPV为9:1、7:3、4:1和2:3等4个混配处理的Q值依次为200、100、31.0和23.8,明显标示了其中“9:1”的Q值最大,被确认为最合理的混配处理.此结果与之前的研究相同.还对该图谱分析方法的可靠性以及应用的可行性等进行了讨论. 相似文献