132 resultados para BRANCHING RATIO


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This paper offers the physical and chemical characterization of a new dextran produced by Leuconostoc mesenteroides FT045B. The chemical structure was determined by Fourier Transform Infrared spectroscopy and 1H Nuclear Magnetic Resonance spectroscopy. The dextran was hydrolyzed by endodextranase; the products were analyzed using thin layer chromatography and compared with those of commercial B-512F dextran. The number-average molecular weight and degree of polymerization of the FT045B dextran were determined by the measurement of the reducing value using the copper bicinchoninate method and the measurement of total carbohydrate using the phenol-sulfuric acid method. The data revealed that the structure of the dextran synthesized by FT045B dextran sucrase is composed of d-glucose residues, containing 97.9% α-(1,6) linkages in the main chains and 2.1% α-(1,3) branch linkages compared with the commercial B-512F dextran, which has 95% α-(1,6) linkages in the main chains and 5% α-(1,3) branch linkages. © 2012 Elsevier Ltd. All rights reserved.

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We evaluated the population dynamics of Acetes americanus Ortmann, 1893 focusing on sex ratio, individual growth, longevity, and the juvenile recruitment period. Samples were collected monthly from January 2006 to June 2007 in the bay of Ubatuba, Brazil. Specimen growth was identified for each gender, and the chosen cohorts were fitted in a von Bertalanffy Growth Model (VBGM); longevity was estimated by the von Bertalanffy inverse equation, considering 99% of the asymptotic length. A total of 6881 individuals (2343 males and 4538 females) were captured. On average the body size (total length) was greater in females (14.64 ± 3.34 mm) than in males (12.27 ± 1.86 mm). The mean growth curves (obtained by grouping the cohorts for each sex), provided estimates of TL∞ = 19.33 mm, k = 0.02 and t0 = -0.12 days for females and TL∞ = 15.13 mm, k = 0.03 and to = -0.07 days for males, where TL∞ is the asymptotic length, k is coefficient of growth and to is the theorical age when the size is equal to 0. Longevity was estimated at 0.61 years for females and 0.50 years for males. The sex ratio tended to favor females, which corroborates with others studies of sergestids. Our finding that males of A. americanus have higher values of k and therefore achieve a smaller size relative to females has been observed in other penaeids. We concluded that this differential growth pattern between the sexes is found across Dendrobranchiata. The life cycles of penaeids have an average duration of approximately 1-2 years, but our results corroborate other studies that estimate a shorter longevity for Acetes, as species of this genus are typically smaller in size. We found continuous recruitment with two main peaks observed during the study period, corroborating previous studies of Acetes. © The Crustacean Society, 2013. Published by Brill NV, Leiden.

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Reuse of industrial and agricultural wastes as supplementary cementitious materials (SCMs) in concrete and mortar productions contribute to sustainable development. In this context, fluid catalytic cracking catalyst residue (spent FCC), a byproduct from the petroleum industry and petrol refineries, have been studied as SCM in blended Portland cement in the last years. Nevertheless, another environmental friendly alternative has been conducted in order to produce alternative binders with low CO2 emissions. The use of aluminosilicate materials in the production of alkali-activated materials (AAMs) is an ongoing research topic which can present low CO2 emissions associated. Hence, this paper studies some variables that can influence the production of AAM based on spent FCC. Specifically, the influence of SiO 2/Na2O molar ratio and the H2O/spent FCC mass ratio on the mechanical strength and microstructure are assessed. Some instrumental techniques, such as SEM, XRD, pH and electrical conductivity measurements, and MIP are performed in order to assess the microstructure of formed alkali-activated binder. Alkali activated mortars with compressive strength up to 80 MPa can be formed after curing for 3 days at 65°C. The research demonstrates the potential of spent FCC to produce alkali-activated cements and the importance of SiO2/Na2O molar ratio and the H2O/spent FCC mass ratio in optimising properties and microstructure. © 2013 Elsevier Ltd. All rights reserved.

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The present study was designed to compare Day 14 bovine embryos that were produced entirely in vitro using the post-hatching development (PHD) system with in vivo-derived embryos without or with transient PHD culture from Day 7 to Day 14. Embryos on Day 14 were used for sex determination and gene expression analysis of PLAC8, KRT8, CD9, SLC2A1, SLC2A3, PGK1, HSF1, MNSOD, HSP70 and IFNT using real-time quantitative (q) polymerase chain reaction (PCR). First, Day 7 in vivo-and in vitro-produced embryos were subjected to the PHD system. A higher rate of survival was observed for in vitro embryos on Day 14. Comparing Day 14 embryos produced completely in vivo or completely in vitro revealed that the mean size of the former group was greater than that of the latter (10.29±1.83 vs 2.68±0.33mm, respectively). Expression of the HSP70 and SLC2A1 genes was down-and upregulated, respectively, in the in vitro embryos. The present study shows that in vitro embryos cultured in the PHD system are smaller than in vivo embryos and that of the 10 genes analysed, only two were differentially expressed between the two groups. These findings indicate that, owing to the poor survival rate, the PHD system is not reliable for evaluation of in vitro embryo quality. © 2013 CSIRO.

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Background: Sex steroid exposure during early human development may influence disease susceptibility. Digit ratio (2D:4D) is a putative marker for prenatal hormone exposure and sensitivity, as well as the action of genes closely related to carcinogenesis. Digit ratio could act as a possible marker for cancer predisposition. Aims: The aim of this study is to investigate the possible correlations between right hand, left hand and right minus left (R. - L) 2D:4D and gastric cancer (GCA) in men and women and assess the correlations with tumor staging and histological diagnosis. Methods: Digital images of the right and left hand palms of patients diagnosed with GCA (n = 57, 42 males, 15 females) and age and sex-matched controls (n = 59, 41 males, 18 females) were obtained. Means for 2D:4D were compared. Data were analyzed by repeated-measures one-way ANOVA and Student's t-test for finger measurements and group comparisons and Pearson's and Spearman's tests for correlations with tumor staging (α = 0.05). Results: GCA group presented significantly higher left 2D:4D, but significantly lower R. - L in comparison to healthy controls, particularly so for males. Digit ratio did not correlate to clinical staging or TNM staging. However, low R. - L was significantly related to adenocarcinomas. Conclusions: Early developmental conditions, including prenatal testosterone seem to play a role on the malignant transformation of gastric lesions. The 2D:4D pattern found for gastric cancer parallels that earlier described for breast cancer. The findings suggest that 2D:4D could add to the list of etiological factors and be a putative marker for the screening of patients' susceptibility to develop gastric cancer. © 2012 Elsevier Ltd.

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Soluble fms-like tyrosine kinase 1 (sFlt-1) is an anti-angiogenic factor released in higher amounts by preeclamptic placentas and it has been implicated in the endothelial dysfunction observed in the disease. In this study we evaluated if circulating sFlt-1/PlGF ratio is useful to predict adverse outcomes in women with early-onset preeclampsia. This is a cohort study of 88 preeclamptic women with singleton pregnancies at ≤35 weeks of gestation. According to definitions used, adverse outcomes occurred in 46.5% (N = 43) of the patients. The median sFlt1/PlGF ratio (25th-75th centile) for all patients evaluated was of 42.26 (13.1-226.1). The median sFlt-1/PlGF ratio among women who had any adverse outcome (N = 43) versus no adverse outcomes (N = 45) was of 227.6 (80.3-346.1) versus 14.4 (3.35-30.0), (P < 0.0001). According to our analyses a sFlt-1/PlGF ratio cut-point of ≥85 gave a sensitivity of 74.0% and specificity of 97.0%. The positive predictive value and the negative predictive value were 96.0% and 80.0%, respectively. The median sFlt-1/PlGF ratio (25th-75th centile) for patients who delivered within <7 days was 260.0 (127.7-404.7) as compared to 14.4 (3.35-34.97) for those patients who delivered within two weeks or more (P < 0.0001). Our results suggest that sFlt-1/PlGF ratio is a promising marker for adverse outcomes in women with early-onset preeclampsia. © 2013 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

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Results are presented from a search for the rare decays Bs0→μ+μ- and B0→μ+μ - in pp collisions at √s=7 and 8 TeV, with data samples corresponding to integrated luminosities of 5 and 20 fb-1, respectively, collected by the CMS experiment at the LHC. An unbinned maximum-likelihood fit to the dimuon invariant mass distribution gives a branching fraction B(Bs0→μ+μ-)=(3.0-0.9+1.0) ×10-9, where the uncertainty includes both statistical and systematic contributions. An excess of Bs0→μ+μ- events with respect to background is observed with a significance of 4.3 standard deviations. For the decay B0→μ+μ- an upper limit of B(B0→μ+μ-)<1.1×10 -9 at the 95% confidence level is determined. Both results are in agreement with the expectations from the standard model. © 2013 CERN. Published by the American Physical Society under the terms of the.

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Bovine herpesvirus 5 (BoHV-5) is an α-herpesvirus that causes neurological disease in young cattle and is also occasionally involved in reproductive disorders. Although there have been many studies of the apoptotic pathways induced by viruses belonging to the family Herpesviridae, there is little information about the intrinsic programmed cell death pathway in host-BoHV-5 interactions. We found that BoHV-5 is able to replicate in both mesenchymal and epithelial cell lines, provoking cytopathology that is characterized by cellular swelling and cell fusion. Viral antigens were detected in infected cells by immunofluorescence assay at 48 to 96 h post-infection (p.i.). At 48 to 72 h p.i., anti-apoptotic BCL-2 antigens were found at higher levels than Bax antigens; the latter is considered a pro-apoptotic protein. Infected cells had increased BCL-2 phenotype cells from 48 to 96 h p.i., based on flow cytometric analysis. At 48 to 96 h p.i., Bax mRNA was not expressed in any of the infected cell monolayers. In contrast, BCL-2 mRNA was found at high levels at all p.i. in both types of cells. BoHV-5 replication apparently modulates BCL-2 expression and gene transcription, enhancing production of virus progeny. © FUNPEC-RP.

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Pós-graduação em Agronomia (Proteção de Plantas) - FCA

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The relative lengths of the 2nd and 4th digits (2D:4D) is a negative biomarker for prenatal testosterone, and low 2D:4D may be associated with aggression. However, the evidence for a 2D:4D-aggression association is mixed. Here we test the hypothesis that 2D:4D is robustly linked to aggression in challenge situations in which testosterone is increased. Participants were exposed to an aggressive video and a control video. Aggression was measured after each video and salivary free testosterone levels before and after each video. Compared to the control video, the aggressive video was associated with raised aggression responses and a marginally significant increase in testosterone. Left 2D:4D was negatively correlated with aggression after the aggressive video and the strength of the correlation was higher in those participants who showed the greatest increases in testosterone. Left 2D:4D was also negatively correlated to the difference between aggression scores in the aggressive and control conditions. The control video did not influence testosterone concentrations and there were no associations between 2D:4D and aggression. We conclude that 2D:4D moderates the impact of an aggressive stimulus on aggression, such that an increase in testosterone resulting from a challenge is associated with a negative correlation between 2D:4D and aggression.