98 research outputs found

    In situ estimation of indigestible compounds contents in cattle feed and feces using bags made from different textiles

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    The objective of this experiment was to evaluate estimates of concentration of indigestible dry matter (iDM), indigestible neutral detergent fiber (iNDF) and indigestible acid detergent fiber (iADF) in samples of cattle feed and feces processed at different particle sizes (1-, 2-, and 3-mm) using bags made from nylon (50 μm), F57 (Ankom®), and non-woven textile (NWT - 100 g/m²) in a in situ evaluation procedure. Eight samples of concentrates, seven samples of forages and two samples of cattle feces were used. The samples were put in the bags according to a ratio of 20 mg of dry matter/cm² of surface by using three bags of each textile for each size of particle, totaling 405 bags, which were submitted to ruminal incubation for 264 hours. The contents of indigestible compounds in the samples were evaluated sequentially. Blank bags were used for microscopic evaluation of textile physical integrity and for evaluation of the physical resistance. The presence of contaminants caused high variability of results of iDM, indicating that its using as internal marker should not be recommended. By using the textiles F57 and NWT, similar estimates for contents of iNDF and iADF were obtained whereas by using nylon (50 μm), the concentration of iNDF was underestimated, possibly because of loss of particles due to its porosity. Nylon presented loss of resistance in all analytical stages, expanding its probality of rupture, especially after extraction with acid detergent. For in situ evaluation of indigestible compounds, it is suggested grinding samples in 2-mm screen sieves.Objetivou-se avaliar as estimativas de concentração de matéria seca (MSi), fibra em detergente neutro (FDNi) e fibra em detergente ácido (FDAi) indigestíveis em amostras de alimentos e fezes bovinas processadas em diferentes tamanhos de partículas (1, 2 e 3 mm) utilizando-se sacos confeccionados com os tecidos nylon (50 μm), F57 (Ankom®) e tecido não-tecido (TNT - 100 g/m²) em procedimento de avaliação in situ. Foram utilizadas oito amostras de alimentos concentrados, sete de alimentos volumosos e duas de fezes bovinas. O material foi acondicionado nos sacos numa relação de 20 mg de matéria seca/cm² de superfície utilizando-se três sacos de cada tecido para cada tamanho de partícula, totalizando 405 sacos, que foram submetidos a incubação ruminal durante 264 horas. Os teores dos compostos indigestíveis nas amostras foram avaliados sequencialmente. Sacos em branco foram utilizados para avaliação microscópica da integridade física dos tecidos e para avaliação da resistência à tração. A presença de contaminantes causou alta variabilidade dos resultados de MSi, o que indica comprometimento de sua aplicação como indicador interno. Utilizando os tecidos F57 e TNT obtiveram-se estimativas similares para os teores de FDNi e FDAi, enquanto com o tecido nylon (50 μm) a concentração de FDNi foi subestimada, possivelmente em decorrência da perda de partículas devido à sua porosidade. O nylon apresentou perda de resistência em todas as etapas analíticas, o que amplia sua probabilidade de ruptura, principalmente após extração com detergente ácido. Para procedimentos in situ de avaliação de compostos indigestíveis, sugere-se a moagem de amostras em peneiras com porosidade de 2 mm

    Search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state in proton-proton collisions at s=13TeV

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    A search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state is presented. The analysis is based on proton-proton collision data recorded by the CMS detector in 2016–2018 at a centre-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 138 fb−1. The search is sensitive to resonances with masses between 1.3 and 6TeV, decaying to bosons that are highly Lorentz-boosted such that each of the bosons forms a single large-radius jet. Machine learning techniques are employed to identify such jets. No significant excess over the estimated standard model background is observed. A maximum local significance of 3.6 standard deviations, corresponding to a global significance of 2.3 standard deviations, is observed at masses of 2.1 and 2.9 TeV. In a heavy vector triplet model, spin-1 Z′ and W′ resonances with masses below 4.8TeV are excluded at the 95% confidence level (CL). These limits are the most stringent to date. In a bulk graviton model, spin-2 gravitons and spin-0 radions with masses below 1.4 and 2.7TeV, respectively, are excluded at 95% CL. Production of heavy resonances through vector boson fusion is constrained with upper cross section limits at 95% CL as low as 0.1 fb. © 2023 The Author(s

    Search for a heavy composite Majorana neutrino in events with dilepton signatures from proton-proton collisions at √s=13 Tev

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    Results are presented of a search for a heavy Majorana neutrino N ⠃ decaying into two same-flavor leptons ⠃ (electrons or muons) and a quark-pair jet. A model is considered in which the N ⠃ is an excited neutrino in a compositeness scenario. The analysis is performed using a sample of proton-proton collisions at & RADIC;s = 13 TeV recorded by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 138 fb-1. The data are found to be in agreement with the standard model prediction. For the process in which the N ⠃ is produced in association with a lepton, followed by the decay of the N ⠃ to a same-flavor lepton and a quark pair, an upper limit at 95% confidence level on the product of the cross section and branching fraction is obtained as a function of the N ⠃ mass mN ⠃ and the compositeness scale ⠄. For this model the data exclude the existence of Ne (N & mu;) for mN ⠃ below 6.0 (6.1) TeV, at the limit where mN ⠃ is equal to ⠄. For mN ⠃ N 1 TeV, values of ⠄ less than 20 (23) TeV are excluded. These results represent a considerable improvement in sensitivity, covering a larger parameter space than previous searches in pp collisions at 13 TeV.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3

    Basement membrane proteoglycans: Modulators Par Excellence of cancer growth and angiogenesis

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    Vascular Endothelial Growth Factor Inhibits Bone Morphogenetic Protein 2 Expression in Rat Mesenchymal Stem Cells

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    Introduction: While several studies report that bone morphogenetic proteins (BMPs) and vascular endothelial growth factor (VEGF) can act synergistically to improve bone tissue engineering, others suggest that VEGF inhibits osteogenesis. The purpose of these experiments was therefore to evaluate the effect of dual transfection of these growth factors and potential mechanisms of interaction on gene expression and osteogenesis in vitro and in vivo. Methods: Marrow-derived mesenchymal stem cells (MSCs) were exposed to recombinant VEGF protein or transfected with adenoviruses encoding BMP2, VEGF, or LacZ in a variety of ratios. Alterations in gene and protein expression in vitro as well as bone formation in vivo were assessed. Results: MSC exposure to AdV-VEGF or recombinant VEGF inhibited BMP2 mRNA expression, protein production, and MSC differentiation. Coculture experiments revealed that BMP2 suppression occurs through both an autocrine and a paracrine mechanism, occurring at the transcriptional level. Compared to controls, cotransfection of VEGF and BMP2 transgenes prevented ectopic bone formation in vivo. Conclusion: VEGF is a potent inhibitor of BMP2 expression in MSCs, and supplementation or overexpression of VEGF inhibits osteogenesis in vitro and ectopic bone formation in vivo. Strategies to utilize MSCs in bone tissue engineering therefore require careful optimization and precise delivery of growth factors for maximal bone formation
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