112,570 research outputs found
Scholarly Communication and Open Access: Concepts and Current Trends
No full textPresentation for the International Workshop on Community Health and Environmental Exposures, at College of Public Health Sciences, Chulalongkorn University, Bangkok, Thailand, January 10, 2012
Digital exhibitions: engaging in public scholarship with primary source materials
No full textThis article was published as Marker, Rhonda J., "Digital Exhibitions: Engaging in Public Scholarship with Primary Source Materials" in Quick Hits: Teaching with the Digital Humanities, edited by Michael Morrone, Christopher Young, Emma Wilson and Tom Wilson, Indiana University Press, 2019. No part of this article may be reproduced, stored in a retrieval system, transmitted, or distributed, in any form, by any means, electronic, mechanical, photographic, or otherwise, without the prior permission of Indiana University Press. For re-use, please contact the Copyright Clearance Center (www.copyright.com, 508-744-3350). For all other permissions, please visit http://iupress.indiana.edu.Peer reviewe
A population genetics model of marker-assisted selection
No full textA deterministic two-loci model was developed to predict genetic response to marker-assisted selection (MAS) in one generation and in multiple generations. Formulas were derived to relate linkage disequilibrium in a population to the proportion of additive genetic variance used by MAS, and in turn to an extra improvement in genetic response over phenotypic selection. Predictions of the response were compared to those predicted by using an infinite-loci model and the factors affecting efficiency of MAS were examined. Theoretical analyses of the present study revealed the nonlinearity between the selection intensity and genetic response in MAS. In addition to the heritability of the trait and the proportion of the marker-associated genetic variance, the frequencies of the selectively favorable alleles at the two loci, one marker and one quantitative trait locus, were found to play an important role in determining both the short- and long-term efficiencies of MAS. The evolution of linkage disequilibrium and thus the genetic response over several generations were predicted theoretically and examined by simulation. MAS dissipated the disequilibrium more quickly than drift alone. In some cases studied, the rate of dissipation was as large as that to be expected in the circumstance where the true recombination fraction was increased by three times and selection was absent
Optimal weighting of information in marker-assisted selection
No full textIn crosses between inbred lines linear regression can be used to estimate marker effects; these marker effects then allow marker-assisted selection (MAS) for quantitative traits. Weighting of marker and phenotypic information in MAS requires estimation of genetic variance associated with the markers: the usual estimators are biased, resulting in too much weight being placed on marker information relative to phenotypic information. In this paper we develop a cross-validation method to remove this bias, and show by simulation that response to selection using this method is almost as high as that achieved using optimal weighting of marker and phenotypic information
Prediction of haplotypes for ungenotyped animals and its effect on marker-assisted breeding value estimation
No full textBackground: In livestock populations, missing genotypes on a large proportion of animals are a major problem to implement the estimation of marker-assisted breeding values using haplotypes. The objective of this article is to develop a method to predict haplotypes of animals that are not genotyped using mixed model equations and to investigate the effect of using these predicted haplotypes on the accuracy of marker-assisted breeding value estimation. Methods: For genotyped animals, haplotypes were determined and for each animal the number of haplotype copies (nhc) was counted, i.e. 0, 1 or 2 copies. In a mixed model framework, nhc for each haplotype were predicted for ungenotyped animals as well as for genotyped animals using the additive genetic relationship matrix. The heritability of nhc was assumed to be 0.99, allowing for minor genotyping and haplotyping errors. The predicted nhc were subsequently used in marker-assisted breeding value estimation by applying random regression on these covariables. To evaluate the method, a population was simulated with one additive QTL and an additive polygenic genetic effect. The QTL was located in the middle of a haplotype based on SNP-markers. Results: The accuracy of predicted haplotype copies for ungenotyped animals ranged between 0.59 and 0.64 depending on haplotype length. Because powerful BLUP-software was used, the method was computationally very efficient. The accuracy of total EBV increased for genotyped animals when marker-assisted breeding value estimation was compared with conventional breeding value estimation, but for ungenotyped animals the increase was marginal unless the heritability was smaller than 0.1. Haplotypes based on four markers yielded the highest accuracies and when only the nearest left marker was used, it yielded the lowest accuracy. The accuracy increased with increasing marker density. Accuracy of the total EBV approached that of gene-assisted BLUP when 4-marker haplotypes were used with a distance of 0.1 cM between the markers. Conclusions: The proposed method is computationally very efficient and suitable for marker-assisted breeding value estimation in large livestock populations including effects of a number of known QTL. Marker-assisted breeding value estimation using predicted haplotypes increases accuracy especially for traits with low heritabilit
Costatoria (Costatoria?) subrotunda (BITTNER, 1901) a Smithian (Lower Triassic) marker from Tethys
No full textThe authors erect Costatoria costata var. subrotunda (Bittner) from Hungarian Lower Triassic to species level. Its subgeneric position is also discussed here. Thus, Costatoria is represented in the Werfen Formation of Dolomites area by two species: C. (Costatoria?) subrotunda (Bittner) from the upper part of Campil Member (Smithian) and C. (Costatoria) costata (Zenker) from Cencenighe and S. Lucano Members (Spathian). C. subrotunda shows a wide geographic distribution and could be considered as a helpful marker of Smithian age.-Author
Crosstalk between activated and inactivated c-Src in hepatocellular carcinoma.
No full textC-Src activity is regulated by tyrosine phosphorylation at two distinct sites, Tyr416 and Tyr527, with opposite effects. However, the clinical roles of these sites in human cancers are not well defined. This study aims to determine whether the alterations and crosstalk of these two sites may contribute to hepatocellular carcinoma (HCC). Specimens from 85 patients who had undergone curative hepatectomy were collected for this study. The patterns of p-Tyr416-Src and p-Tyr527-Src, as well as the non-phosphorylated status for each site, were determined using immunohistochemistry and statistically correlated with clinicopathological characteristics and overall survival rate. The active state of c-Src, p-Tyr416-c-Src, was positively correlated with tumour grade (P=0.062) but inversely correlated with vascular invasion (P=0.071). Its non-phosphorylated status, non-p-Tyr416-c-Src, was positively correlated with tumour stage and grade (P= 0.041 and 0.020). The inactive state of c-Src, p-Tyr527-c-Src, was decreased in male patients but increased HCV-infected patients (P=0.044 and 0.033). The Kaplan-Meier survival curve further showed that increased p-Tyr416-c-Src and decreased non-p-Tyr527-c-Src expression were associated with a poor patient survival rate (P=0.004 and 0.025). Interestingly, the expression of non-p-Tyr416-c-Src was positively correlated with that of p-Tyr527-c-Src in the HCC lesions (P=0.040). In addition, the patients with concomitantly low p-Tyr416-c-Src and non-p-Tyr527-c-Src expression had a prolonged overall survival rate (P=0.030). A multivariable COX regression model showed that p-Tyr416-c-Src expression was an effective predictor for patient survival in HCC [OR =3.78, 95% CI =1.46-9.76; P=0.006]. Our results suggest that the active state of c-Src, p-Tyr416-c-Src, may serve as an independent prognostic marker of patient survival in HCC. Relative levels of other phosphorylated or non-phosphorylated c-Src kinases may also present different statuses during HCC development and require further investigation
Marker-trait associations found for quality traits.
No full textMarker-trait associations found for quality traits.</p
Marker-assisted selection using ridge regression
No full textIn crosses between inbred lines, linear regression can be used to estimate the correlation of markers with a trait of interest; these marker effects then allow marker assisted selection (MAS) for quantitative traits. Usually a subset of markers to include in the model must be selected: no completely satisfactory method of doing this exists. We show that replacing this selection of markers by ridge regression can improve the mean response to selection and reduce the variability of selection response
[Texas Historical Commission Marker: Judge C. C. Binkley]
No full textPhotograph of the Texas Historical Commission marker for Judge C. C. Binkley (January 12, 1826 - March 15, 1886) in Sherman, Texas. Text: Christopher Columbus Binkley came to Texas in 1852 and became a law partner of Sherman's first mayor. He served as district judge from 1870 to 1874 and Republican national committeeman for many years. As a founder and the first President of the Merchants and Planters Bank, Judge Binkley was the financial leader of the county and was considered one of the most trusted and outstanding businessmen of his day. Upon his death, Judge Binkley was acknowledged as Sherman's leading citizen. Recorded - 1997
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