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61.
《Developmental cell》2021,56(16):2273-2283.e3
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Bayes estimates in one-way and two-way models 总被引:1,自引:0,他引:1
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B. T. Baune T. Suslow C. Beśte E. Birosova K. Domschke C. Sehlmeyer C. Konrad 《Genes, Brain & Behavior》2010,9(5):459-466
Set‐shifting and maintenance are complex cognitive processes, which are often impaired in schizophrenia. The genetic basis of these processes is poorly understood. We aimed to investigate the association between genetic variants of the metabotropic glutamate receptor 3 (GRM3) and cognitive set‐shifting in healthy individuals. The relationship between 14 selected single nucleotide polymorphisms (SNPs) of the GRM3 gene and cognitive set‐shifting as measured by perseverative errors using the modified card sorting test (MCST) was analysed in a sample of N = 98 young healthy individuals (mean age in years: 22.7 ± 0.19). Results show that SNP rs17676277 is related to the performance on the MCST. Subjects with the TT genotype showed significantly less perseverative errors as compared with the AA (P = 0.025) and AT (P = 0.0005) and combined AA/AT genotypes (P = 0.0005). Haplotype analyses suggest the involvement of various SNPs of the GRM3 gene in perseverative error processing in a dominant model of inheritance. The findings strongly suggest that the genetic variation (rs17676277 and three haplotypes) in the metabotropic GRM3 is related to cognitive set‐shifting in healthy individuals independent of working memory. However, because of a relatively small sample size for a genetic association study, the present results are tentative and require replication. 相似文献
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采用美景度评价法(SBE法)对广东省生态景观林带进行评价,分析影响生态景观林带景观水平的主要因子,探讨生态景观林带景观构成要素与景观质量的关系。结果表明,不同专业、性别、学历、年龄的人群在森林审美态度上具有一致性,其评判结果能够反映森林美景度的实际情况;对53张照片评价SBE值,最大为1.4454,最小为-1.6917;对美景度影响较大的4个因子,即色彩丰富度(X6)、色泽明度(X7)、生活型(X8)、生长状况(X9),建立的多元线性回归模型是 Y=1.902-0.346X6-0.461X7+ 0.206X8-0.584X9。 相似文献
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Joel Tellinghuisen 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):886-894
Background
Questions about the reliability of parametric standard errors (SEs) from nonlinear least squares (LS) algorithms have led to a general mistrust of these precision estimators that is often unwarranted.Methods
The importance of non-Gaussian parameter distributions is illustrated by converting linear models to nonlinear by substituting eA, ln A, and 1/A for a linear parameter a. Monte Carlo (MC) simulations characterize parameter distributions in more complex cases, including when data have varying uncertainty and should be weighted, but weights are neglected. This situation leads to loss of precision and erroneous parametric SEs, as is illustrated for the Lineweaver-Burk analysis of enzyme kinetics data and the analysis of isothermal titration calorimetry data.Results
Non-Gaussian parameter distributions are generally asymmetric and biased. However, when the parametric SE is < 10% of the magnitude of the parameter, both the bias and the asymmetry can usually be ignored. Sometimes nonlinear estimators can be redefined to give more normal distributions and better convergence properties.Conclusion
Variable data uncertainty, or heteroscedasticity, can sometimes be handled by data transforms but more generally requires weighted LS, which in turn require knowledge of the data variance.General significance
Parametric SEs are rigorously correct in linear LS under the usual assumptions, and are a trustworthy approximation in nonlinear LS provided they are sufficiently small — a condition favored by the abundant, precise data routinely collected in many modern instrumental methods. 相似文献70.
NMπ—improved re‐implementation of NM+, a software for estimating gene dispersal and mating patterns
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Igor J. Chybicki 《Molecular ecology resources》2018,18(1):159-168
This study introduces the NMπ computer program designed for estimation of plant mating system and seed and pollen dispersal kernels. NMπ is a re‐implementation of the NM+ program and provides new features such as support for multicore processors, explicit treatment of dioecy, the possibility of incorporating uniparentally cytoplasmic markers, the possibility of assessing assortative mating due to phenotypic similarity and inference about offspring genealogies. The probability model of parentage (the neighbourhood model) accounts for missing data and genotyping errors, which can be estimated along with regular parameters of the mating system. The program has virtually no restrictions with respect to a number of individuals, markers or phenotypic characters. A console version of NMπ can be run under a wide variety of operating systems, including Windows, Linux or Mac OS. For Windows users, a graphical user interface is provided to facilitate operating the software. The program, user manual and example data are available on http://www.ukw.edu.pl/pracownicy/plik/igor_chybicki/3694/ . 相似文献