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Flow coupling during three-phase gravity drainage
We measure the three-phase oil relative permeability k(ro) by conducting unsteady-state drainage experiments in a 0.8 m water-wet sand pack. We find that when starting from capillary-trapped oil, k(ro) shows a strong dependence on both the flow of water and the water saturation and a weak dependence on oil saturation, contrary to most models. The observed flow coupling between water and oil is stronger in three-phase flow than two-phase flow, and cannot be observed in steady-state measurements. The results suggest that the oil is transported through moving gas-oil-water interfaces (form drag) or momentum transport across stationary interfaces (friction drag). We present a simple model of friction drag which compares favorably to the experimental data.University of Texas at AustinCenter for Frontiers of Subsurface Energy SecurityUS Department of Energy, Office of Basic Energy Sciences DE-SC0001114Petroleum and Geosystems Engineerin
A Colour Rendering Index for Dichromats
We propose a method of evaluating the colour rendering quality of light sources tailored to dichromatic vision. To the best of our knowledge, the proposed color rendering index (CRI) is the first such index to be specifically designed for dichromats. Previous CRIs have been defined only for trichromats and they generally rely on measuring ΔE colour differences in a standardized uniform colour space such as CAM02-UCS. Since these spaces are defined only for trichromatic colour vision these methods do not generalize to the case of dichromatic colour vision. The proposed dichromat CRI is based on the metamer mismatch index, which applies to both the trichromatic and dichromatic cases
The effect of peanut pod on performance, small intestine pH and ileum bacteria population in broiler chickens
This experiment was designed to assess the hypothesis that feeding broilers with peanut pod as an insoluble fibre source will result in improved gut digestive capacity growth performance. The experimental diets consisted of a control diet and three diets containing 25, 50, or 75 g peanut pod /kg. The dietary peanut pod, especially at the 50 g/kg level decreased feed intake of the experimental groups. In grower phase, the best weight gain was recorded in the broiler chickens fed the diet containing 75 g peanut pod /kg. All the peanut pod containing diets decreased grower phase feed conversion ratio compared to the control group. In the finisher phase, the growth rate and feed conversion ratio were not affected by the experimental diets. The gizzard weight and gastrointestinal length was increased in the chickens fed 75 g peanut pod /kg, and these groups showed the lowest pH for gizzard content. In the ileum, the birds fed 25 g peanut pod /kg had a higher Lactobacillus population than the 75 g peanut pod /kg group; and the birds fed 25 g peanut pod had lower Escherichia coli (E. coli) population, compared to the control group. The positive effects of dietary insoluble fibre on the growth performance of broilers in this study were probably a result of favourable changes in the bacteria populations and also an increase in digestive capacity of gastrointestinal.Keywords: Broilers, gut pH, ileum bacteria, peanut po
Human cytochrome b5 reductase: structure, function, and potential applications
Cytochrome b5 reductase is a flavoprotein that is produced as two different isoforms that have different localizations.
The amphipathic microsomal isoform, found in all cell types with the exception of erythrocytes, consists of one
hydrophobic membrane-anchoring domain and a larger hydrophilic flavin catalytic domain. The soluble cytochrome
b5 reductase isoform, found in human erythrocytes, is a truncated protein that is encoded by an alternative transcript
and consists of the larger domain only. Cytochrome b5 reductase is involved in the transfer of reducing equivalents
from the physiological electron donor, NADH, via an FAD domain to the small molecules of cytochrome b5. This protein
has received much attention from researchers due to its involvement in many oxidation and reduction reactions, such
as the reduction of methemoglobin to hemoglobin. Autosomal cytochrome b5 reductase gene deficiency manifests
with the accumulation of oxidized Fe+3 and recessive congenital methemoglobinemia in humans. In this article,
we provide a comprehensive overview of the structure and function of cytochrome b5 reductase from different
eukaryotic sources and its potential use in the food industry, biosensor, and diagnostic areas
Interaction between genotype and climates for Holstein milk production traits in Iran
This study was designed to investigate the interaction between genotype and climate for milk and fat production traits of Iranian Holstein dairy herds. Milk and fat production data were grouped in 5 climates, on the basis of Extended De Martonne method. (Co)Variance components and genetic parameters of first lactation records from 514 herds were estimated by DFREML procedure. Estimation of genetic parameters by univariate animal model showed that heritability of milk and fat yields were from 0.22 to 0.30 and 0.06 to 0.26, respectively; that proved by the results of multivariate model. Genetic correlations between different climates ranged from 0.66 to 1 for milk yield and 0.16 to 1 for fat yield, respectively. Calculated genetic correlation between milk production traits in 5 various climates of Iran showed that there is a significant interaction between humid climate with other climates for both milk and fat yield traits. Using Spearman and Rank correlation for estimation of correlation between bulls breading values, for two traits showed the significant genotype by environment interaction between humid climate and Meditrranean climate for milk yield and between humid climate and other climates for fat yield.Key words: Holstein, genetic correlation, breeding value, genotype by environment interaction
Nonviral Production of Human Interleukin-7 in Spodoptera Frugiperda Insect Cells as a Soluble Recombinant Protein
Human interleukin-7 (hIL-7) is a cytokine secreted by the stromal cells of the red marrow. It is important for proliferation during certain stages of B-cell maturation and for T and NK cell survival, development, and homeostasis. It is a critical growth factor for enhancement and recovery of the immune T-cell. Because of its strong immunomodulatory effects, hIL-7 may become a valuable supplementary agent for immunotherapeutical treatments in patients with HIV infection or immunodeficiency. Human IL-7 has previously been produced in various protein expression systems. In this paper, we present an alternative expression system, in Spodoptera frugiperda cells, for the production of hIL-7 using nonlytic vector systems. This system allows generation of correctly translated and accurately processed heterologous proteins as soluble recombinant proteins. Here we report plasmid construction, transfection, and consequent expression of hIL-7 using this nonlytic insect cell expression system. The levels of secreted hIL-7 in a small scale experiment reached a level of 1.7 μg·1−1 under serum-free cell culture conditions
Effects of exogenous tannase enzyme on growth performance, antioxidant status, immune response, gut morphology and intestinal microflora of chicks fed grape pomace
An experiment was conducted to study the effects of dietary addition of tannase to feed of chicks including grape pomace (GP) on growth performance, antioxidant status, immune response, blood parameters, gut morphology, intestinal microflora, liver function, and histopathological responses. The experimental diets were i) control (corn and soybean diet) (C); ii) C+10%GP; iii) C+10%GP+T1 (500 mg/kg tannase enzyme); and iv) C+10% GP+T2 (1000 mg/kg tannase enzyme). At 10 days old, the bodyweight (BW) and average daily gain (ADG) of the birds fed the diet supplemented with GP was lower compared with the control group. In contrast with the control, supplementation of diets with 10%GP+1000 mg/kg tannase elevated superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and depressed the malondialdehyde (MDA) level in serum. The addition of GP to the chicken diets had a significant impact on the total anti- sheep red blood cells (SRBC) titers and IgG, and IgM antibodies at 21 and 42 days old. The muscularis thickness of the chicken duodenum decreased in the Trial 3 compared with control groups. The inclusion of GP in the chicken diets reduced the concentration of Escherichia coli and increased that of Lactobacillus compared with the control. The results of the present study suggest that the inclusion of up to 10 percent GP in diets did not adversely affect broiler growth performance, and supplementation of tannase improved the antioxidant status and immune responses,and increased the caecal populations of beneficial bacteria in the cecum of broiler chickens.Keywords: Broiler chickens, histopathological responses, glutathione peroxidase, polyphenol, sheep red blood cell
Effects of grape pomace and vitamin E on performance, antioxidant status, immune response, gut morphology and histopathological responses in broiler chickens
We investigated the effects of grape pomace (GP) and vitamin E on the performance, antioxidant status, immune response, gut morphology and histopathological responses in broiler chickens. Two hundred and fifty male broiler chickens (Ross 308) were allocated to five dietary treatments (50 birds/treatment) in a completely randomized design. The experimental diets were as follows: i) Control corn-soybean meal diet (C); ii) C + Vitamin E (200 mg/kg of α-tocopherol acetate); iii) The diet containing 5%GP; iv) The diet containing 7.5% GP; v) The diet containing 10% GP. No differences were found in performance of the experimental birds. Birds fed 7.5% GP showed a significant increase in superoxide dismutase (SOD), glutathione peroxidise (GSH-Px) activity and reduced malondialdehyde (MDA) concentration. Antibody titer against Newcastle disease virus (NDV) at 42 days (d) of age in the control and 7.5% GP fed groups were lower than others. The primary IgM concentration of birds fed 10% GP was higher than the birds fed the control diet, the vitamin E supplemented diet or the diet containing 5% GP. The secondary titer against sheep red blood cells (SRBC) was increased significantly in the birds fed 10% GP and the secondary IgG concentration of birds fed 10% GP was higher than the birds fed the control diet and the diets containing 5% or 7.5% GP. In duodenum part of small intestine, villus height/crypt depth ratio and muscularis thickness were decreased. The results of the present study suggest that the inclusion of up to 10% GP in diets did not adversely affect broiler chickens’ performance and improved the antioxidant and immune responses of broiler chickens.Keywords: Glutathione peroxidise, polyphenol, poultry, red blood cells α-tocopherol acetate, sheep, superoxide dismutas
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