9,780 research outputs found
Improving single-cell cloning workflow for gene editing in human pluripotent stem cells
The availability of human pluripotent stem cells (hPSCs) and progress in genome engineering technology have altered the way we approach scientific research and drug development screens. Unfortunately, the procedures for genome editing of hPSCs often subject cells to harsh conditions that compromise viability: a major problem that is compounded by the innate challenge of single-cell culture. Here we describe a generally applicable workflow that supports single-cell cloning and expansion of hPSCs after genome editing and single-cell sorting. Stem-Flex and RevitaCell supplement, in combination with Geltrex or Vitronectin (VN), promote reliable single-cell growth in a feeder-free and defined environment. Characterization of final genome-edited clones reveals that pluripotency and normal karyotype are retained following this single-cell culture protocol. This time-efficient and simplified culture method paves the way for high-throughput hPSC culture and will be valuable for both basic research and clinical applications. Keywords: Human pluripotent stem cells, Embryonic stem cells, Single-cell cloning, Induced pluripotent stem cells, hPSCs, hESCs, Genome engineering, CRISPR-Cas
Clustering Coefficients of Protein-Protein Interaction Networks
The properties of certain networks are determined by hidden variables that
are not explicitly measured. The conditional probability (propagator) that a
vertex with a given value of the hidden variable is connected to k of other
vertices determines all measurable properties. We study hidden variable models
and find an averaging approximation that enables us to obtain a general
analytical result for the propagator. Analytic results showing the validity of
the approximation are obtained. We apply hidden variable models to
protein-protein interaction networks (PINs) in which the hidden variable is the
association free-energy, determined by distributions that depend on
biochemistry and evolution. We compute degree distributions as well as
clustering coefficients of several PINs of different species; good agreement
with measured data is obtained. For the human interactome two different
parameter sets give the same degree distributions, but the computed clustering
coefficients differ by a factor of about two. This shows that degree
distributions are not sufficient to determine the properties of PINs.Comment: 16 pages, 3 figures, in Press PRE uses pdflate
Potential of air-sparged hydrocyclone flotation in environmental technology
Journal ArticleAir-sparged hydrocyclone (ASH) flotation is a high capacity flotation technology originally developed in the Department of Metallurgical Engineering at the University of Utah for processing mineral resources. However, the technology has been found to be useful in industrial waste processing, recycling for the recovery of secondary resources, and in remediation of environmental disasters. For example, areas in which the ASH technology has demonstrated potential include: cleaning of waste coal fuels, air stripping to remove volatile organics from drinking and process water, water disinfection by ozone or chlorine sparging, dispersed oil removal from water, and contaminated soil remediation
Macroscopic quantum coherence in spinor condensates confined in an anisotropic potential
We investigate the macroscopic quantum coherence of a spin-1 Rb condensate
confined in an anisotropic potential. Under the single-mode approximation, we
show that the system can be modeled as a biaxial quantum magnet due to the
interplay between the magnetic dipole-dipole interaction and the anisotropic
potential. By applying a magnetic field along the hard-axis, we show that the
tunneling splitting oscillates as a function of the field strength. We also
propose an experimental scheme to detect the oscillatory behavior of the
tunneling splitting by employing the Landau-Zener tunneling.Comment: 5 pages, 4 figure
Plasma Urea Can Be Used To Identify The Protein Requirements of Group-penned Finishing (130 to 220 lb) Barrows and Gilts Fed Corn-soybean Diets
In this study, growth performance data from finishing pigs indicate the response of barrows and gilts to dietary protein concentration was maximized with a 15 percent protein corn-soybean meal diet. Review of the response of plasma urea concentration to dietary protein intake indicated that, in this study, the protein requirement of barrows was between 12 and 15 percent and the protein requirement for gilts was between 15 and 18 percent. Based on the many findings in the literature documenting that protein requirements ( percent of the diet) of gilts are greater than those of barrows, we believe the use of plasma urea is an alternative approach to using growth performance data for establishing the protein (amino acid) requirements of finishing pigs. Identifying a small number of pigs for blood sampling may provide a less intensive method to help gain insight into the protein requirements of barrows and gilts during the finishing period. Future research will focus on refining the plasma urea technique to identify the response of barrows and gilts to dietary protein. Specifically, we are interested in pursuing the application of this methodology to commercial conditions
The Effect of Protein Intake on Growth Performance, Plasma Urea Concentration, Liver Weight, and Arginase Activity of Finishing Barrows and Gilts
An experiment was conducted to evaluate the effects of dietary protein concentration on growth performance, plasma urea concentration, liver weight and liver arginase activity of finishing (138 lb) barrows and gilts. Average daily feed intake, arginase activity and plasma urea concentration were greater in barrows than in gilts, whereas liver weight was lighter in barrows than in gilts. These data suggest gilts are affected more negatively by high protein diets than barrows. We believe the changes in liver weight and urea cycle enzymes (arginase) are related to these feed intake differences
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