38 research outputs found

    Characterization of Bovine Induced Pluripotent Stem Cells by Lentiviral Transduction of Reprogramming Factor Fusion Proteins

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    Pluripotent stem cells from domesticated animals have potential applications in transgenic breeding. Here, we describe induced pluripotent stem (iPS) cells derived from bovine fetal fibroblasts by lentiviral transduction of Oct4, Sox2, Klf4 and c-Myc defined-factor fusion proteins. Bovine iPS cells showed typical colony morphology, normal karyotypes, stained positively for alkaline phosphatase (AP) and expressed Oct4, Nanog and SSEA1. The CpG in the promoter regions of Oct4 and Nanog were highly unmethylated in bovine iPS cells compared to the fibroblasts. The cells were able to differentiate into cell types of all three germ layers in vitro and in vivo. In addition, these cells were induced into female germ cells under defined culture conditions and expressed early and late female germ cell-specific genes Vasa, Dazl, Gdf9, Nobox, Zp2, and Zp3. Our data suggest that bovine iPS cells were generated from bovine fetal fibroblasts with defined-factor fusion proteins mediated by lentivirus and have potential applications in bovine transgenic breeding and gene-modified animals

    Short-term effect of supplemental yeast extract without or with feed enzymes on growth performance, immune status and gut structure of weaned pigs challenged with Escherichia coli lipopolysaccharide

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    Abstract Background This study investigated the response of piglets receiving a yeast extract without or with a multi-enzyme mixture compared with an antimicrobial growth promoter (AGP) on performance, immune status and gut structure after an E. coli lipopolysaccharide (LPS) challenge. Thirty-six pigs were allotted to six treatments including: a non-challenged control (NCC); LPS-challenged control (CC); CC + AGP; CC + yeast extract; CC + enzymes; and CC + enzymes + yeast extract. On d 7, pigs were bled and thereafter injected with LPS or sterile saline. Blood samples were collected at 6, 48, and 96 h post-challenge. After 96 h post-challenge, pigs were euthanized to obtain duodenal, jejunal and ileal samples. Results Overall (d 1 to 11), compared with CC pigs, AGP attenuated the LPS-induced reduction in ADG (P = 0.004), ADFI (P = 0.03) and gain/feed ratio (P = 0.01). At 6 h post-challenge, AGP pigs had lower plasma urea N (PUN; P = 0.02) and serum TNF- α concentration (P = 0.07), and higher platelet count (P = 0.04) and serum IL-10 concentration (P = 0.02) than CC pigs. At 48 h post-challenge, AGP pigs had lower PUN (P = 0.02) than CC pigs, whereas enzymes + yeast extract interacted non-additively (P = 0.001) to reduce PUN. At 96 h post-challenge, AGP pigs had lower PUN (P = 0.02) and higher duodenal (P = 0.03), jejunal (P = 0.01) and ileal (P = 0.07) villus height than CC pigs. In addition, enzymes + yeast extract interacted additively and non-additively to reduce ileal IFN-γ (P  0.10) were observed between AGP and enzymes + yeast extract pigs on other measured parameters except for the downregulation of ileal IFN-γ (P < 0.0001) and TNF-α (P = 0.003) in enzymes + yeast extract pigs at 96 h post-challenge. Conclusions The LPS challenged piglets receiving enzymes + yeast extract showed beneficial responses in gut structure and immunity commensurate with those receiving antibiotics, though the latter had better overall growth performance

    Application of Random Forest Algorithm on Tornado Detection

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    Tornadoes are highly destructive small-scale extreme weather processes in the troposphere. The weather radar is one of the most effective remote sensing devices for the monitoring and early warning of tornadoes. The existing tornado detection algorithms based on radar data are unsupervised and have strict multi-altitude constraints, such as the tornado detection algorithm based on tornado vortex signatures (TDA-TVS), which may lead to high false alarm rates, and the performance of the detection algorithm is greatly affected by the radar data quality control algorithm. A novel TDA-RF algorithm based on the random forest (RF) classification algorithm is proposed for real-time tornado identification of the S-band China new generation of Doppler weather radar (CINRAD-SA). The TDA-RF algorithm uses velocity features to identify tornadoes and adds features related to reflectivity and velocity spectrum width in radar level-II data. Historical CINRAD-SA tornado data from 2006–2015 are used to construct the tornado dataset and train the TDA-RF model. The performance of TDA-RF is evaluated using CINRAD-SA data from five tornadoes of 2016–2020 with enhanced Fujita(EF) scale ratings ranging from EF0 to EF4 and distances from 10 to 130 km to the radar. TDA-RF performs well overall with the probability of detection (POD), false alarm ratio (FAR), and critical success index (CSI) of 71%, 29%, and 55%, respectively. Moreover, the TDA-RF improves POD and CSI, and reduces FAR compared to the TDA-TVS. The maximum tornado early-warning time of TDA-RF is 17 min, and the average is 6 min; TDA-RF can provide classification probability according to the tornado generation and development process to facilitate tracking ability

    Application of Random Forest Algorithm on Tornado Detection

    No full text
    Tornadoes are highly destructive small-scale extreme weather processes in the troposphere. The weather radar is one of the most effective remote sensing devices for the monitoring and early warning of tornadoes. The existing tornado detection algorithms based on radar data are unsupervised and have strict multi-altitude constraints, such as the tornado detection algorithm based on tornado vortex signatures (TDA-TVS), which may lead to high false alarm rates, and the performance of the detection algorithm is greatly affected by the radar data quality control algorithm. A novel TDA-RF algorithm based on the random forest (RF) classification algorithm is proposed for real-time tornado identification of the S-band China new generation of Doppler weather radar (CINRAD-SA). The TDA-RF algorithm uses velocity features to identify tornadoes and adds features related to reflectivity and velocity spectrum width in radar level-II data. Historical CINRAD-SA tornado data from 2006&ndash;2015 are used to construct the tornado dataset and train the TDA-RF model. The performance of TDA-RF is evaluated using CINRAD-SA data from five tornadoes of 2016&ndash;2020 with enhanced Fujita(EF) scale ratings ranging from EF0 to EF4 and distances from 10 to 130 km to the radar. TDA-RF performs well overall with the probability of detection (POD), false alarm ratio (FAR), and critical success index (CSI) of 71%, 29%, and 55%, respectively. Moreover, the TDA-RF improves POD and CSI, and reduces FAR compared to the TDA-TVS. The maximum tornado early-warning time of TDA-RF is 17 min, and the average is 6 min; TDA-RF can provide classification probability according to the tornado generation and development process to facilitate tracking ability

    Dietary butyrate glycerides modulate intestinal microbiota composition and serum metabolites in broilers

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    Abstract Butyrate can modulate the immune response and energy expenditure of animals and enhance intestinal health. The present study investigated changes in the intestinal microbiota composition and serum metabolites of young broilers in response to 3,000 ppm butyrate in the form of butyrate glycerides (BG) via pyrosequencing of bacterial 16S rRNA genes and nuclear magnetic resonance (NMR). The dietary treatment did not affect the alpha diversity of intestinal microbiota, but altered its composition. Thirty-nine key operational taxonomic units (OTUs) in differentiating cecal microbiota community structures between BG treated and untreated chickens were also identified. Bifidobacterium was, in particular, affected by the dietary treatment significantly, showing an increase in not only the abundance (approximately 3 fold, P ≤ 0.05) but also the species diversity. The (NMR)-based analysis revealed an increase in serum concentrations of alanine, low-density and very low-density lipoproteins, and lipids (P ≤ 0.05) by BG. More interestingly, the dietary treatment also boosted (P ≤ 0.05) serum concentrations of bacterial metabolites, including choline, glycerophosphorylcholine, dimethylamine, trimethylamine, trimethylamine-N-oxide, lactate, and succinate. In conclusion, the data suggest the modulation of intestinal microbiota and serum metabolites by BG dietary treatment and potential contribution of intestinal bacteria to lipid metabolism/energy homeostasis in broilers

    Selected lactic acid-producing bacterial isolates with the capacity to reduce Salmonella translocation and virulence gene expression in chickens.

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    BACKGROUND:Probiotics have been used to control Salmonella colonization/infection in chickens. Yet the mechanisms of probiotic effects are not fully understood. This study has characterized our previously-selected lactic acid-producing bacterial (LAB) isolates for controlling Salmonella infection in chickens, particularly the mechanism underlying the control. METHODOLOGY/PRINCIPAL FINDINGS:In vitro studies were conducted to characterize 14 LAB isolates for their tolerance to low pH (2.0) and high bile salt (0.3-1.5%) and susceptibility to antibiotics. Three chicken infection trials were subsequently carried out to evaluate four of the isolates for reducing the burden of Salmonella enterica serovar Typhimurium in the broiler cecum. Chicks were gavaged with LAB cultures (10(6-7) CFU/chick) or phosphate-buffered saline (PBS) at 1 day of age followed by Salmonella challenge (10(4) CFU/chick) next day. Samples of cecal digesta, spleen, and liver were examined for Salmonella counts on days 1, 3, or 4 post-challenge. Salmonella in the cecum from Trial 3 was also assessed for the expression of ten virulence genes located in its pathogenicity island-1 (SPI-1). These genes play a role in Salmonella intestinal invasion. Tested LAB isolates (individuals or mixed cultures) were unable to lower Salmonella burden in the chicken cecum, but able to attenuate Salmonella infection in the spleen and liver. The LAB treatments also reduced almost all SPI-1 virulence gene expression (9 out of 10) in the chicken cecum, particularly at the low dose. In vitro treatment with the extracellular culture fluid from a LAB culture also down-regulated most SPI-1 virulence gene expression. CONCLUSIONS/SIGNIFICANCE:The possible correlation between attenuation of Salmonella infection in the chicken spleen and liver and reduction of Salmonella SPI-1 virulence gene expression in the chicken cecum by LAB isolates is a new observation. Suppression of Salmonella virulence gene expression in vivo can be one of the strategies for controlling Salmonella infection in chickens

    Reversible Surface Dual-Pattern with Simultaneously Dynamic Wrinkled Topography and Fluorescence

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    The reversible surface patterns with fluorescence and topography can possibly enable information recording and reading and provide an important alternative to realize the higher information security. We demonstrated a reversible dual-pattern with simultaneously responsive fluorescence and topography using an anthracene (AN) and naphthalene diimide (NDI) containing copolymer (PAN-NDI-BA) as the skin layer, in which the reversible photodimerization of AN can simultaneously control the cross-linking and CT interaction between AN and NDI. Upon irradiation with UV light and thermal treatment, the resulting pattern assumes a reversible change between smooth and wrinkled states, and its fluorescence changes reversibly from red to white to blue-green. The smart surfaces with dynamic hierarchical wrinkles and fluorescence were achieved by selective irradiation with photomasks and can be employed for potential applications in smart displays and anticounterfeiting
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