2,495 research outputs found

    Ex Situ Conservation Of Holstein-Friesian Cattle - Comparing The Dutch, French And USA Germplasm Collections

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    The establishment of gene banks using cryopreservation to secure the genetic diversity of farm breeds have been widely assessed. France, the Netherlands and the USA were among the first countries to organize national cryobanks and these banks are now 10 to 20 years old. All three countries have started Holstein-Friesian (HF) collections to conserve as much genetic diversity as possible for this globally important breed. In order better understand the diversity captured in these collections, the genetic variability of HF collections within and between countries was assessed, and genetic variability of germplasm collections were compared with active bulls in each country. The overall aim of the project was to determine the breed’s security and to guide future collection activities

    Meta-analysis of RNA-seq expression data across species, tissues and studies.

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    BackgroundDifferences in gene expression drive phenotypic differences between species, yet major organs and tissues generally have conserved gene expression programs. Several comparative transcriptomic studies have observed greater similarity in gene expression between homologous tissues from different vertebrate species than between diverse tissues of the same species. However, a recent study by Lin and colleagues reached the opposite conclusion. These studies differed in the species and tissues analyzed, and in technical details of library preparation, sequencing, read mapping, normalization, gene sets, and clustering methods.ResultsTo better understand gene expression evolution we reanalyzed data from four studies, including that of Lin, encompassing 6-13 tissues each from 11 vertebrate species using standardized mapping, normalization, and clustering methods. An analysis of independent data showed that the set of tissues chosen by Lin et al. were more similar to each other than those analyzed by previous studies. Comparing expression in five common tissues from the four studies, we observed that samples clustered exclusively by tissue rather than by species or study, supporting conservation of organ physiology in mammals. Furthermore, inter-study distances between homologous tissues were generally less than intra-study distances among different tissues, enabling informative meta-analyses. Notably, when comparing expression divergence of tissues over time to expression variation across 51 human GTEx tissues, we could accurately predict the clustering of expression for arbitrary pairs of tissues and species.ConclusionsThese results provide a framework for the design of future evolutionary studies of gene expression and demonstrate the utility of comparing RNA-seq data across studies

    Evaluating School District 428\u27s Curriculum Media Development Center\u27s Clientele

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    The Curriculum Media Development Center was conceptualized by the Illinois Office of Education and Vocational Services and the Illinois Depaartment of Corrections to meet the need for specially developed instructional materials in reading and math for Title I students being served by School District 428. The project began in 1974 and was located at the Illinois Youth Center, St. Charles. However, during 1979, it became apparent that because of its location in Kane County, the Curriculum Media Development Center was providing services primarily to those institutions in the northeast quadrant of Illinois. In January of 1980 the decision was made to relocate this project to the Department of Corrections headquarters in Springfield, Illinois in an effort to make it more accessible to all institutions within the state. This study represents an attempt by this researcher to determine if the Curriculum Media Development Center is in fact more responsive to the requests for materials from all institutions, both adult and juvenile, since its relocation to Springfield; and from which group of educators, Title I or Core Curriculum, those requests originated. Data for this study was gathered from an analysis of the production request forms for Fiscal Year 1980 and Fiscal Year 1982, the years immediately preceding and following the year in which the Curriculum Media Development Center was moved to Springfield. In Fiscal Year 1980, forty-three percent of all requests originated in the Juvenile Division. In Fiscal Year 1982 only twenty-two percent of all requests originated in the Juvenile Division, and seventy-eight percent from the Adult Division. Coincidentally, this is the same percentage of students served by School District 428 in each division. The data does indicate that relocating the Curriculum Media Development Center to Springfield generated more requests from those institutions located in the southern portion of the state (six adult, two juvenile). However, the data does not support the contention that the juvenile division has suffered because of the move but rather that the adult division has simply submitted more requests during the period of this study

    Evaluating School District 428\u27s Curriculum Media Development Center\u27s Clientele

    Get PDF
    The Curriculum Media Development Center was conceptualized by the Illinois Office of Education and Vocational Services and the Illinois Depaartment of Corrections to meet the need for specially developed instructional materials in reading and math for Title I students being served by School District 428. The project began in 1974 and was located at the Illinois Youth Center, St. Charles. However, during 1979, it became apparent that because of its location in Kane County, the Curriculum Media Development Center was providing services primarily to those institutions in the northeast quadrant of Illinois. In January of 1980 the decision was made to relocate this project to the Department of Corrections headquarters in Springfield, Illinois in an effort to make it more accessible to all institutions within the state. This study represents an attempt by this researcher to determine if the Curriculum Media Development Center is in fact more responsive to the requests for materials from all institutions, both adult and juvenile, since its relocation to Springfield; and from which group of educators, Title I or Core Curriculum, those requests originated. Data for this study was gathered from an analysis of the production request forms for Fiscal Year 1980 and Fiscal Year 1982, the years immediately preceding and following the year in which the Curriculum Media Development Center was moved to Springfield. In Fiscal Year 1980, forty-three percent of all requests originated in the Juvenile Division. In Fiscal Year 1982 only twenty-two percent of all requests originated in the Juvenile Division, and seventy-eight percent from the Adult Division. Coincidentally, this is the same percentage of students served by School District 428 in each division. The data does indicate that relocating the Curriculum Media Development Center to Springfield generated more requests from those institutions located in the southern portion of the state (six adult, two juvenile). However, the data does not support the contention that the juvenile division has suffered because of the move but rather that the adult division has simply submitted more requests during the period of this study

    Relevance of pseudospin symmetry in proton-nucleus scattering

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    The manifestation of pseudospin-symmetry in proton-nucleus scattering is discussed. Constraints on the pseudospin-symmetry violating scattering amplitude are given which require as input cross section and polarization data, but no measurements of the spin rotation function. Application of these constraints to p-58Ni and p-208Pb scattering data in the laboratory energy range of 200 MeV to 800 MeV, reveals a significant violation of the symmetry at lower energies and a weak one at higher energies. Using a schematic model within the Dirac phenomenology, the role of the Coulomb potential in proton-nucleus scattering with regard to pseudospin symmetry is studied. Our results indicate that the existence of pseudospin-symmetry in proton-nucleus scattering is questionable in the whole energy region considered and that the violation of this symmetry stems from the long range nature of the Coulomb interaction.Comment: 22 pages including 9 figures, correction of 1 reference, revision of abstract and major modification of chapter 4, Fig. 6, and Fig. 7; addition of Fig. 8 and Fig.

    Space shuttle high pressure auxiliary propulsion system

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    Requirements review for space shuttle auxiliary propulsion syste
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