924 resultados para 54-419


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Colour-magnitude diagrams (CMDs) of the Small Magellanic Cloud (SMC) star cluster NGC 419, derived from Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) data, reveal a well-delineated secondary clump located below the classical compact red clump typical of intermediate-age populations. We demonstrate that this feature belongs to the cluster itself, rather than to the underlying SMC field. Then, we use synthetic CMDs to show that it corresponds very well to the secondary clump predicted to appear as a result of He-ignition in stars just massive enough to avoid e(-)-degeneracy settling in their H-exhausted cores. The main red clump instead is made of the slightly less massive stars which passed through e(-) degeneracy and ignited He at the tip of the red giant branch. In other words, NGC 419 is the rare snapshot of a cluster while undergoing the fast transition from classical to degenerate H-exhausted cores. At this particular moment of a cluster`s life, the colour distance between the main-sequence turn-off and the red clump(s) depends sensitively on the amount of convective core overshooting, Lambda(c). By coupling measurements of this colour separation with fits to the red clump morphology, we are able to estimate simultaneously the cluster mean age (1.35(-0.04)(+0.11) Gyr) and overshooting efficiency (Lambda(c) = 0.47(-0.04)(+0.14)). Therefore, clusters like NGC 419 may constitute important marks in the age scale of intermediate-age populations. After eye inspection of other CMDs derived from HST/ACS data, we suggest that the same secondary clump may also be present in the Large Magellanic Cloud clusters NGC 1751, 1783, 1806, 1846, 1852 and 1917.

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The phytopathogen Xylella fastidiosa produces long type IV pili and short type I pili involved in motility and adhesion. In this work, we have investigated the role of sigma factor sigma(54) (RpoN) in the regulation of fimbrial biogenesis in X. fastidiosa. An rpoN null mutant was constructed from the non-pathogenic citrus strain J1a12, and microarray analyses of global gene expression comparing the wild type and rpoN mutant strains showed few genes exhibiting differential expression. In particular, gene pilA1 (XF2542), which encodes the structural pilin protein of type IV pili, showed decreased expression in the rpoN mutant, whereas two-fold higher expression of an operon encoding proteins of type I pili was detected, as confirmed by quantitative RT-PCR (qRT-PCR) analysis. The transcriptional start site of pilA1 was determined by primer extension, downstream of a sigma(54)-dependent promoter. Microarray and qRT-PCR data demonstrated that expression of only one of the five pilA paralogues, pilA1, was significantly reduced in the rpoN mutant. The rpoN mutant made more biofilm than the wild type strain and presented a cell-cell aggregative phenotype. These results indicate that sigma(54) differentially regulates genes involved in type IV and type I fimbrial biogenesis, and is involved in biofilm formation in X. fastidiosa.

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Background:  Whether calcium supplementation can reduce osteoporotic fractures is uncertain. We did a meta-analysis to include all the randomised trials in which calcium, or calcium in combination with vitamin D, was used to prevent fracture and osteoporotic bone loss.

Methods:  We identified 29 randomised trials (n=63 897) using electronic databases, supplemented by a hand-search of reference lists, review articles, and conference abstracts. All randomised trials that recruited people aged 50 years or older were eligible. The main outcomes were fractures of all types and percentage change of bone-mineral density from baseline. Data were pooled by use of a random-effect model.

Findings:  In trials that reported fracture as an outcome (17 trials, n=52 625), treatment was associated with a 12% risk reduction in fractures of all types (risk ratio 0·88, 95% CI 0·83–0·95; p=0·0004). In trials that reported bone-mineral density as an outcome (23 trials, n=41 419), the treatment was associated with a reduced rate of bone loss of 0·54% (0·35–0·73; p<0·0001) at the hip and 1·19% (0·76–1·61%; p<0·0001) in the spine. The fracture risk reduction was significantly greater (24%) in trials in which the compliance rate was high (p<0·0001). The treatment effect was better with calcium doses of 1200 mg or more than with doses less than 1200 mg (0·80 vs 0·94; p=0·006), and with vitamin D doses of 800 IU or more than with doses less than 800 IU (0·84 vs 0·87; p=0·03).

Interpretation:  Evidence supports the use of calcium, or calcium in combination with vitamin D supplementation, in the preventive treatment of osteoporosis in people aged 50 years or older. For best therapeutic effect, we recommend minimum doses of 1200 mg of calcium, and 800 IU of vitamin D (for combined calcium plus vitamin D supplementation).

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This study aimed to examine cost disparity and nutritional choices within the
City of Yarra (Yarra), targeting three suburbs that have low- and high-rise
estates: Richmond, Fitzroy, and Collingwood. The healthy food basket
(HFB) was modeled on the Queensland Healthy Food Access Basket for a
six-person family for a fortnight and was constructed to include food items
that are common to ethnic groups living in Yarra. The HFB food item costs
were sampled across 29 food outlets in Yarra. The average cost of HFB per fortnight
for a family of six was significantly lower in Richmond (Mean = $419.26)
than in Collingwood (Mean = $519.28) and in Fitzroy (Mean = $433.98). While
costs for cereal groups, dairy, meats and alternatives, and non-core were
comparable across the suburbs, significant differences were noticed for fruit,
legumes and vegetables. Geographic location alone explained 54% of the
variance in HFB price (F2,26 = 15.23, p < 0.001) and 32.7% in the variance of
fruit, vegetable and legumes (F2,26 = 7.72, p < 0.001). The effect of geographic
location remained consistent after controlling for the type of food
outlets. The type of food outlets had a non-significant effect on the variance
of prices. Richmond had a greater number variety of fruit, vegetables, and
legumes (F2, 26 = 5.7, p < 0.01) and an overall lower number of missing items
(F2, 26 = 3.9, p < 0.05) than Collingwood and Fitzroy. The diversity of food
available in the three suburbs was more likely to reflect the Vietnamese,
Chinese and East-Timorese shopping pattern than the rest of other ethnic

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Este texto tem como objetivo analisar o papel e a atuação da Assessoria Econômica no segundo governo Vargas a partir de entrevistas que alguns de seus membros concederam ao Centro de Pesquisa e Documentação de História Contemporânea do Brasil (CPDOC), da Fundação Getulio Vargas, ao longo da década de 1980. Ao avaliar a posteriori a curta, porém intensa, experiência que tiveram como “braço imediato” do presidente da República,2 os depoimentos de Rômulo de Almeida, Cleantho Paiva Leite e Ignacio Rangel tornam-se fontes particularmente interessantes para quem está interessado em entender os meandros do processo de industrialização, em particular o papel que nele desempenharam as chamadas “elites técnicas”.

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This paper analyzes the Brazilian Supreme Court (STF) Decision (ADPF n. 54) in which the court, by majority of votes, stated that the termination of the pregnancy of an anencephalic fetus does not constitute a crime of abortion. The paper analyzes the arguments used by the judges in their opinions to show that they agree on the conclusion, but strongly disagree on their reasons, with the result that the court remains deeply divided on the legal concept of life. The paper then points to the fact that the possibility of different majority positions regarding the decision and the arguments that justify it is not accidental, but the result of the court’s structure, which does not guarantee the collective rationality of the court’s decisions.

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Reproductive rate is an important component of economic success in livestock production. Parturition interval (IEP) is a direct measure of the productivity of the animal. Long IEP reduce the number of calves produced per year. The objective this study was to determine the distribution of parturitions across month and to evaluate factors affecting IEP. The data included 7,588 parturitions of Murrah, Mediterranean and Carabobo buffalo from 10 herds in Southern and South-eastern Brazil. The analysis of distribution of parturitions evaluated the effects of month, year and their interaction on birth date of calves by using a Chi-Square test in SAS PROC FREQ (SAS Institute, Cary, NC, USA). Parturition intervals (n = 2,630) were evaluated using analysis of variance in SAS PROC GLM. The model for IEP included the fixed effects of season (December to May = 1, June to November = 2), year, season x year, sex of the preceding parturition, age of weaning of the previous calf, and herd. All sources of variation were significant (P<0.0001) except sex of the preceding parturition (P <0.85). The mean IEP was 446.7 +/- 10.4 days, for seasons 1 and 2 IEP were 419.8 +/- 11.3 and 473.6 +/- 40.7 days, respectively, a difference of 54 days. As weaning age increased there was a lengthening of IEP. Buffalo in Brazil showed seasonal parturition with calving concentrated from January to April, although the frequency by month differed across years (P<0.0001). These months also had the lowest calving interval.