473 research outputs found
Extracting Classical Correlations from a Bipartite Quantum System
In this paper we discuss the problem of splitting the total correlations for
a bipartite quantum state described by the Von Neumann mutual information into
classical and quantum parts. We propose a measure of the classical correlations
as the difference between the Von Neumann mutual information and the relative
entropy of entanglement. We compare this measure with different measures
proposed in the literature.Comment: 5 pages, 1 figur
CYTOLOGICAL EVIDENCE FOR A RELATIONSHIP BETWEEN NORMAL HEMATOPOIETIC COLONY-FORMING CELLS AND CELLS OF THE LYMPHOID SYSTEM
The relationship between hematopoietic colony-forming stem cells and cells in the thymus and lymph nodes of unirradiated mice has been investigated using a chromosome-marker technique. It was found that a high proportion of cells in the thymus may belong to the same clone as normal hematopoietic colony-forming cells. It was also found that cells belonging to the same clone as colony-forming cells may reach the lymph nodes, and that nodes containing such cells can participate in an immunological response against sheep red cells. Either the precursors of cells in thymus and lymph node are identical with hematopoietic colony-forming cells, or they are both descendants of a common precursor which has not yet been identified. The results are compatible with the view that cells of the hematopoietic system and the immune system may be derived from the same stem cell
MULTIPLICATION OF ANIMAL CELLS IN SUSPENSION MEASURED BY COLONY COUNTS
Archived with permission from the National Academy of Sciences USA. Originally published in Proceedings of the National Academy of Sciences USA volume 43 issue 6. Please refer to www.pnas.org for this series of publications. Author holds all copyright for this article.During the past few years the development of new techniques for the cultivation
of animal cells in vitro has facilitated the quantitative study of many aspects of
cell biology. At present the most commonly used method of propagating cell
strains is based on the ability of cells to multiply while attached to a glass surface.
The cells may be subcultured by removing them from the surface into suspension
and then distributing them into other vessels, where they will again adhere to the
glass and populate the surface. This procedure has been developed by Earle and
his associates into the so-called quantitative replicate culture technique and
applied to a variety of studies with animal cells. Despite the technical advance
represented by this method, there are, nevertheless, serious experimental limitations inherent in the use of glass surfaces for cultivating large cell populations. Perhaps
the most obvious of these is the problem of removing representative samples at
will during the growth of a cell population. In addition, subculture requires the
removal of cells from the surface, with consequent risk of cell injury.Aided in part by grants from the National Foundation for Infantile Paralysis, the Public Health Service of the National Institutes of Health of the United States, the National Cancer Institute of Canada, and the W. B. Boyd Memorial Fun
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A design guide for energy-efficient research laboratories
This document--A Design Guide for Energy-Efficient Research Laboratories--provides a detailed and holistic framework to assist designers and energy managers in identifying and applying advanced energy-efficiency features in laboratory-type environments. The Guide fills an important void in the general literature and compliments existing in-depth technical manuals. Considerable information is available pertaining to overall laboratory design issues, but no single document focuses comprehensively on energy issues in these highly specialized environments. Furthermore, practitioners may utilize many antiquated rules of thumb, which often inadvertently cause energy inefficiency. The Guide helps its user to: introduce energy decision-making into the earliest phases of the design process, access the literature of pertinent issues, and become aware of debates and issues on related topics. The Guide does focus on individual technologies, as well as control systems, and important operational factors such as building commissioning. However, most importantly, the Guide is intended to foster a systems perspective (e.g. right sizing) and to present current leading-edge, energy-efficient design practices and principles
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Data for Genetic Analysis Workshop (GAW) 15 Problem 2, Genetic Causes of Rheumatoid Arthritis and Associated Traits
For Genetic Analysis Workshop 15 Problem 2, we organized data from several ongoing studies designed to identify genetic and environmental risk factors for rheumatoid arthritis. Data were derived from the North American Rheumatoid Arthritis Consortium (NARAC), collaboration among Canadian researchers, the European Consortium on Rheumatoid Arthritis Families (ECRAF), and investigators from Manchester, England. All groups used a common standard for defining rheumatoid arthritis, but NARAC also further selected for a more severe phenotype in the probands. Genotyping and family structures for microsatellite-based linkage analysis were provided from all centers. In addition, all centers but ECRAF have genotyped families for linkage analysis using SNPs and these data were additionally provided. NARAC also had additional data from a dense genotyping analysis of a region of chromosome 18 and results from candidate gene studies, which were provided. Finally, smoking influences risk for rheumatoid arthritis, and data were provided from the NARAC study on this behavior as well as some additional phenotypes measuring severity. Several questions could be evaluated using the data that were provided. These include comparing linkage analysis using single-nucleotide polymorphisms versus microsatellites and identifying credible regions of linkage outside the HLA region on chromosome 6p13, which has been extensively documented; evaluating the joint effects of smoking with genetic factors; and identifying more homogenous subsets of families for whom genetic susceptibility might be stronger, so that linkage and association studies may be more efficiently conducted
Data for Genetic Analysis Workshop (GAW) 15 Problem 2, genetic causes of rheumatoid arthritis and associated traits
For Genetic Analysis Workshop 15 Problem 2, we organized data from several ongoing studies designed to identify genetic and environmental risk factors for rheumatoid arthritis. Data were derived from the North American Rheumatoid Arthritis Consortium (NARAC), collaboration among Canadian researchers, the European Consortium on Rheumatoid Arthritis Families (ECRAF), and investigators from Manchester, England. All groups used a common standard for defining rheumatoid arthritis, but NARAC also further selected for a more severe phenotype in the probands. Genotyping and family structures for microsatellite-based linkage analysis were provided from all centers. In addition, all centers but ECRAF have genotyped families for linkage analysis using SNPs and these data were additionally provided. NARAC also had additional data from a dense genotyping analysis of a region of chromosome 18 and results from candidate gene studies, which were provided. Finally, smoking influences risk for rheumatoid arthritis, and data were provided from the NARAC study on this behavior as well as some additional phenotypes measuring severity. Several questions could be evaluated using the data that were provided. These include comparing linkage analysis using single-nucleotide polymorphisms versus microsatellites and identifying credible regions of linkage outside the HLA region on chromosome 6p13, which has been extensively documented; evaluating the joint effects of smoking with genetic factors; and identifying more homogenous subsets of families for whom genetic susceptibility might be stronger, so that linkage and association studies may be more efficiently conducted
Correspondence : In support of the IES method of evaluating light source colour rendition
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Integration of Sequence Data from a Consanguineous Family with Genetic Data from an Outbred Population Identifies PLB1 as a Candidate Rheumatoid Arthritis Risk Gene
Integrating genetic data from families with highly penetrant forms of disease together with genetic data from outbred populations represents a promising strategy to uncover the complete frequency spectrum of risk alleles for complex traits such as rheumatoid arthritis (RA). Here, we demonstrate that rare, low-frequency and common alleles at one gene locus, phospholipase B1 (PLB1), might contribute to risk of RA in a 4-generation consanguineous pedigree (Middle Eastern ancestry) and also in unrelated individuals from the general population (European ancestry). Through identity-by-descent (IBD) mapping and whole-exome sequencing, we identified a non-synonymous c.2263G>C (p.G755R) mutation at the PLB1 gene on 2q23, which significantly co-segregated with RA in family members with a dominant mode of inheritance (Pâ=â0.009). We further evaluated PLB1 variants and risk of RA using a GWAS meta-analysis of 8,875 RA cases and 29,367 controls of European ancestry. We identified significant contributions of two independent non-coding variants near PLB1 with risk of RA (rs116018341 [MAFâ=â0.042] and rs116541814 [MAFâ=â0.021], combined Pâ=â3.2Ă10â6). Finally, we performed deep exon sequencing of PLB1 in 1,088 RA cases and 1,088 controls (European ancestry), and identified suggestive dispersion of rare protein-coding variant frequencies between cases and controls (Pâ=â0.049 for C-alpha test and Pâ=â0.055 for SKAT). Together, these data suggest that PLB1 is a candidate risk gene for RA. Future studies to characterize the full spectrum of genetic risk in the PLB1 genetic locus are warranted
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