925 resultados para Farsalia, Batalla de, 48 a.C.
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Species of the genus Culex Linnaeus have been incriminated as the main vectors of lymphatic filariases and are important vectors of arboviruses, including West Nile virus. Sequences corresponding to a fragment of 478 bp of the cytochrome c oxidase subunit I gene, which includes part of the barcode region, of 37 individuals of 17 species of genus Culex were generated to establish relationships among five subgenera, Culex, Phenacomyia, Melanoconion, Microculex, and Carrollia, and one species of the genus Lutzia that occurs in Brazil. Bayesian methods were employed for the phylogenetic analyses. Results of sequence comparisons showed that individuals identified as Culex dolosus, Culex mollis, and Culex imitator possess high intraspecific divergence (3.1, 2.3, and 3.5%, respectively) when using the Kimura two parameters model. These differences were associated either with distinct morphological characteristics of the male genitalia or larval and pupal stages, suggesting that these may represent species complexes. The Bayesian topology suggested that the genus and subgenus Culex are paraphyletic relative to Lutzia and Phenacomyia, respectively. The cytochrome c oxidase subunit I sequences may be a useful tool to both estimate phylogenetic relationships and identify morphologically similar species of the genus Culex.
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We derive fundamental parameters of the embedded cluster DBSB 48 in the southern nebula Hoffleit 18 and the very young open cluster Trumpler 14, by means of deep JHK(s) infrared photometry. We build colour-magnitude and colour-colour diagrams to derive reddening and age, based on main sequence and pre-main sequence distributions. Radial stellar density profiles are used to study cluster structure and guide photometric diagram extractions. Field-star decontamination is applied to uncover the intrinsic cluster sequences in the diagrams. Ages are inferred from K-excess fractions. A prominent pre-main sequence population is present in DBSB 48, and the K-excess fraction f(K) = 55 +/- 6% gives an age of 1.1 +/- 0.5 Myr. A mean reddening of A(Ks) = 0.9 +/- 0.03 was found, corresponding to A(v) = 8.2 +/- 0.3. The cluster CMD is consistent with the far kinematic distance of 5 kpc for Hoffleit 18. For Trumpler 14 we derived similar parameters as in previous studies in the optical, in particular an age of 1.7 +/- 0.7 Myr. The fraction of stars with infrared excess in Trumpler 14 is f(K) = 28 +/- 4%. Despite the young ages, both clusters are described by a King profile with core radii R-core = 0.46 +/- 0.05 pc and R-core = 0.35 +/- 0.04 pc, respectively, for DBSB 48 and Trumpler 14. Such cores are smaller than those of typical open clusters. Small cores are probably related to the cluster formation and/or parent molecular cloud fragmentation. In DBSB 48, the magnitude extent of the upper main sequence is Delta K-s approximate to 2 mag, while in Trumpler 14 it is Delta K-s approximate to 5 mag, consistent with the estimated ages. (c) 2008 Elsevier B.V. All rights reserved.
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We report the first observation of two Cabibbo-suppressed ecay modes, Xi(+)(c) -> Sigma(+)pi(-)pi(+) and Xi c+ -> Sigma(-)pi(+)pi(+). We observe 59 +/- 14 over a background of 87, and 22 +/- 8 over a background of 13 events, respectively, for the signals. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 Gev/c Sigma(-) beam. The branching ratios of the decays relative to the Cabibbo-favored Xi c+ -> Xi(-)pi(+)pi(+) are measured to be B(Xi(+)(c) -> Sigma(+)pi(-)pi(+))/B(Xi(+)(c) -> Xi(-)pi(+)pi(+)) = 0.48 +/- 0.20, and B(Xi(+)(c) -> Sigma(-)pi(+)pi(+))/B(Xi(+)(c) -> Sigma(-)pi(+)pi(+)) = 0.18 +/- 0.09, respectively. We also report branching ratios for the same decay modes of the Delta(+)(c) relative to Delta(+)(c) -> pK(-)pi(+.) (C) 2008 Elsevier B.V. All rights reserved.
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This article describes a solid-state NMR (SSNMR) investigation of the influence of hydration and chemical cross-linking on the molecular dynamics of the constituents of the bovine pericardium (BP) tissues and its relation to the mechanical properties of the tissue. Samples of natural phenetylamine-diepoxide (DE)- and glutaraldehyde (GL)-fixed BP were investigated by (13)C cross-polarization SSNMR to probe the dynamics of the collagen, and the results were correlated to the mechanical properties of the tissues, probed by dynamical mechanical analysis. For samples of natural BP, the NMR results show that the higher the hydration level the more pronounced the molecular dynamics of the collagen backbone and sidechains, decreasing the tissue`s elastic modulus. In contrast, in DE- and GL-treated samples, the collagen molecules are more rigid, and the hydration seems to be less effective in increasing the collagen molecular dynamics and reducing the mechanical strength of the samples. This is mostly attributed to the presence of cross-links between the collagen plates, which renders the collagen mobility less dependent on the water absorption in chemically treated samples. Copyright (C) 2010 John Wiley & Sons, Ltd.
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This study was undertaken to evaluate the prevalence of GB virus C (GBV-C) viraemia and anti-E2 antibody, and to assess the effect of co-infection with GBV-C and HIV during a 10-year follow-up of a cohort of 248 HIV-infected women. Laboratory variables (mean and median CD4 counts, and HIV and GBV-C viral loads) and clinical parameters were investigated. At baseline, 115 women had past exposure to GBV-C: 57 (23%) were GBV-C RNA positive and 58 (23%) were anti-E2 positive. There was no statistical difference between the groups (GBV-C RNA + /anti-E2 -, GBV-C RNA - /anti-E2 + and GBV-C RNA - /anti-E2 -) regarding baseline CD4 counts or HIV viral loads (P = 0.360 and 0.713, respectively). Relative risk of death for the GBV-C RNA + /anti-E2 - group was 63% lower than that for the GBV-C RNA - /anti-E2 - group. Multivariate analysis demonstrated that only HIV loads >= 100,000 copies/mL and AIDS-defining illness during follow-up were associated with shorter survival after AIDS development. It is likely that antiretroviral therapy (ART) use in our cohort blurred a putative protective effect related to the presence of GBV-C RNA.
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Cytochrome c exhibits two positively charged sites: site A containing lysine residues with high pK(a) values and site L containing ionizable groups with pK(aobs),values around 7.0. This protein feature implies that cytochrome c can participate in the fusion of mitochondria and have its detachment from the inner membrane regulated by cell acidosis and alkalosis. In this study, We demonstrated that both horse and tuna cytochrome c exhibited two types of binding to inner mitochondrial membranes that contributed to respiration: a high-affinity and low-efficiency pi-I-independent binding (microscopic dissociation constant K(sapp2), similar to 10 nM) and a low-affinity and high-efficiency pH-dependent binding that for horse cytochrome c had a pK(a) of similar to 6.7. For tuna cytochrome c (Lys22 and His33 replaced with Asn and Trp, respectively), the effect of pH on K(sapp1), was less striking than for the horse heme protein, and both tuna and horse cytochrome c had closed K(sapp1) values at pH 7.2 and 6.2, respectively. Recombinant mutated cytochrome c H26N and H33N also restored the respiration of the cytochrome c-depleted mitoplast in a pH-dependent manner. Consistently, the detachment of cytochrome c from nondepleted mitoplasts was favored by alkalinization, suggesting that site Lionization influences the participation of cytochrome c in the respiratory chain and apoptosis.
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To assess cooperation between G-CSF signals and C/EBP, we characterized Ba/F3 pro-B cell lines expressing C/EBPWT-ER and the G-CSF receptor (GCSFR). In these lines, GCSFR signals can be evaluated independent of their effect on C/EBP levels. G-CSF alone did not induce the MPO, NE, LF, or PU.1 RNAs, and C/EBPWT-ER alone stimulated low-level MPO and high-level PU.1 expression. Simultaneous activation of the GCSFR and C/EBPWT-ER markedly increased MPO and NE induction at 24 h, and LF mRNA was detected at 48 h. G-CSF did not increase endogenous GCSFR, endogenous C/EBP or exogenous C/EBPWT-ER levels, and C/EBPWT-ER did not induce endogenous or exogenous GCSFR. Several GCSFR mutants were also co-expressed with C/EBPWT-ER. Mutation of all four cytoplasmic tyrosines prevented NE induction but enhanced MPO induction. Mutation of Y704 was required for increased MPO induction. Consistent with this finding, removing IL-3 without G-CSF addition enabled MPO, but not NE, induction by C/EBPWT-ER. GCSFR signals or related signals from other receptors may cooperate with C/EBP to direct differentiation of normal myeloid stem cells.
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<b>Background:</b> Although there is cross-sectional evidence that changes in the immune system contribute to the pathophysiology of depression, longitudinal data capable of elucidating cause and effect relationships are lacking. <br /><br /><b>Aims: </b>We aimed to determine whether subclinical systemic inflammation, as measured by serum high-sensitivity C-reactive protein (hsCRP) concentration, is associated with an increased risk of de novo major depressive disorder. <br /><br /><b>Method:</b> Major depressive disorder was diagnosed using a clinical interview (SCID-I/NP). This is a retrospective cohort study; from a population-based sample of 1494 randomly selected women recruited at baseline during the period 1994-7, 822 were followed for a decade and provided measures of both exposure and outcome. Of these women, 644 (aged 20-84 years) had no prior history of depression at baseline and were eligible for analysis. <br /><br /><b>Results:</b> During 5827 person-years of follow-up, 48 cases of de novo major depressive disorder were identified. The hazard ratio (HR) for depression increased by 44% for each standard deviation increase in log-transformed hsCRP (ln-hsCRP) (HR = 1.44, 95% CI 1.04-1.99), after adjusting for weight, smoking and use of non-steroidal anti-inflammatory drugs. Further adjustment for other lifestyle factors, medications and comorbidity failed to explain the observed increased risk for depression. <br /><br /><b>Conclusions:</b> Serum hsCRP is an independent risk marker for de novo major depressive disorder in women. This supports an aetiological role for inflammatory activity in the pathophysiology of depression.
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Morphine withdrawal is characterized by physical symptoms and a negative affective state. The 41 amino acid polypeptide corticotropin-releasing hormone (CRH) is hypothesized to mediate, in part, both the negative affective state and the physical withdrawal syndrome. Here, by means of dual-immunohistochemical methodology, we examined the co-expression of the c-Fos protein and CRH following naloxone-precipitated morphine withdrawal. Rats were treated with slow-release morphine 50 mg/kg (subcutaneous, s.c.) or vehicle every 48 h for 5 days, then withdrawn with naloxone 5 mg/kg (s.c.) or saline 48 h after the final morphine injection. Two hours after withdrawal rats were perfused transcardially and their brains were removed and processed for immunohistochemistry. We found that naloxone-precipitated withdrawal of morphine-dependent rats increased c-Fos immunoreactivity (IR) in CRH positive neurons in the paraventricular hypothalamus. Withdrawal of morphine-dependent rats also increased c-Fos-IR in the central amygdala and bed nucleus of the stria terminalis, however these were in CRH negative neurons.<br />
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We determined the stability of infectious hematopoietic necrosis virus (IHNV) and viral hemorrhagic septicemia virus (VHSV) suspended in either fish processing plant effluent blood water (EBW) or culture media and examined the effectiveness of UVC radiation to inactivate IHNV and VHSV suspended in both solutions. Without exposure to UVC, IHNV and VHSV were maintained in 4°C blood water for up to 48 hours without significant reduction in virus titer. However when exposed to UVC radiation using a low pressure mercury vapour lamp collimated beam, IHNV and VHSV were inactivated, and the efficacy of UVC radiation was dependent upon the solution and virus type being treated. A 3-log reduction for VHSV and IHNV in culture media was achieved at 3.28 and 3.84 mJ cm-2, respectively. The UV dose needed for a 3-log reduction of VHSV in EBW was 3.82 mJ cm-2. However, exposure of IHNV in EBW to the maximum UVC dose tested (4.0 mJ cm-2) only led to a 2.26-log-reduction. Factors such as particle size, and possible association of viruses with suspended EBW particulate, were not investigated in this study, but may have contributed to the difference in UVC effectiveness. Future work should emphasize improved filtration methods prior to UV treatment of processing plant EBW at an industrial scale.<br />
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Background: Published clinical trials of the treatment of HCV are largely multicentre prospective pharmaceutical trials. Patients in clinical trials tend to have more favorable outcomes than patients in the 'real-world', due to strict patient selection and differences in treatment conditions and available resources. Objectives: To assess the outcomes of Hepatitis C infected patients treated at the Barwon Health Liver Clinic with combination Pegylated interferon (PEG-IFN) and Ribavirin (RBV) therapy and to determine factors associated with a treatment response. Methods: Retrospective review of patients who received treatment for Hepatitis C at our institution's Liver Clinic from January 2001-September 2011. Patient demographics, comorbidities, treatment-related parameters and side effects were extracted from medical records and analyzed. Results: A total of 190 patients (120 male, 70 female) with a mean age of 42.8 years (range 20-68 years) commenced treatment. The most common genotype was genotype 3 (48.9%), followed by genotype 1 (42.6%). 150 of 190 patients (78.9%) completed treatment and had end of treatment data available. 107 of 182 patients, (58.8%) for whom sustained virologic response (SVR) rate data was available achieved an SVR. Overall response rates were; 46.9%, 68.8% and 62.4% in genotypes 1, 2 and 3 respectively. The response rate was significantly lower in 29 patients with documented cirrhosis (20.7%). Age, diabetes and alcohol abuse did not predict treatment response in our cohort. Side effects reported in 81.6% of patients included general malaise, hematological disturbance and psychiatric issues, and necessitated cessation of therapy in 16 patients (8.4%) and dose reduction in 26 patients (13.7%). Conclusions: Response rates to combination PEG-IFN and RBV therapy at our institution are comparable to other 'real-world' and pharmaceutical registration trials. Side effects of combination therapy were prominent but resulted in fewer discontinuations of therapy compared to pharmaceutical trials.
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Existem evidncias crescentes indicando a associao entre dietas ricas em frutas e vegetais e a diminuio da incidncia de cncer. O suco de laranja (OJ) pode ser includo entre os alimentos com potencial quimioprotetor e seu estudo muito relevante pelo amplo consumo desta bebida. O OJ possui vrios nutrientes e compostos bioativos com atividades antioxidante, antimutagnica, anticarcinognica e antiaterognica, entre outras. A vitamina C (Vit C) um dos nutrientes mais abundantes no OJ, e o nico nutriente que pode ser provido em quantidade superior recomendao diria por uma nica poro de 200 mL de OJ. A Vit C, a exemplo de outros componentes do OJ, pode ser tanto benfica quanto malfica para os sistemas biolgicos, dependendo do contexto metablico. Neste sentido, vrios nutrientes presentes no OJ tm sido identificados como mutagnicos ou carcinognicos, especialmente quando administrados de forma isolada. Este estudo utilizou o ensaio Cometa alcalino em sangue de camundongos (in vivo) para avaliar: 1) a genotoxicidade do OJ e da Vit C; 2) a genotoxicidade do FeSO4 e do CuSO4: 3) o efeito modulador do OJ e da Vit C sobre a genotoxicidade do FeSO4 e CuSO4, bem como do metilmetanosulfonato (MMS) e da ciclofosfamida (CP). A verso alcalina do ensaio Cometa foi utilizada para avaliar o dano no DNA em clulas brancas do sangue perifrico de camundongos. Adicionalmente, os nveis de cobre e ferro no sangue e no fgado dos camundongos tratados com metais e OJ foram avaliados pela metodologia de PIXE (Particle-Induced X-ray Emission). Grupos com pelo menos 6 camundongos (metade de cada sexo) foram tratados por gavage com uma ou duas doses de gua (controle), CP, MMS, FeSO4 ou CuSO4. OJ (0.1 mL/Kg) foi administrado tanto antes (pr-tratamento) quanto aps a administrao das substncias-teste (ps-tratamento). A Vit C (1 e 30 mg/Kg) foi administrada apenas no ps-tratamento. O dano no DNA foi avaliado 24 e 48 h aps o incio do tratamento. Aps 24 h, o OJ induziu um suave aumento no dano no DNA, enquanto a Vit C foi genotxica (30 mg/Kg > 1 mg/Kg). O tratamento duplo com Vit C (a 0 e a 24 h) induziu uma resposta genotxica cumulativa a 48 h, que foi mais intensa para a dose maior. O FeSO4 e o CuSO4 foram genotxicos aps 24 h, mas tiveram seu dano efetivamente reparado aps 48 h do tratamento. O pr-tratamento com OJ reduziu a genotoxicidade do FeSO4 e do CuSO4 (efeito preventivo). O ps-tratamento com OJ tambm reduziu a genotoxicidade do CuSO4 (efeito reparador). O OJ mostrou tanto efeito preventivo quanto reparador sobre a genotoxicidade do MMS. O OJ teve apenas efeito reparador sobre a CP. Ambas doses de Vit C aumentaram os danos no DNA causados pelo FeSO4 e pelo CuSO4. Adicionalmente, os nveis de cobre e ferro no sangue e no fgado dos camundongos tratados com metais e OJ foram avaliados pela metodologia de PIXE (Particle-Induced X-ray Emission). Grupos com pelo menos 6 camundongos (metade de cada sexo) foram tratados por gavage com uma ou duas doses de gua (controle), CP, MMS, FeSO4 ou CuSO4. OJ (0.1 mL/Kg) foi administrado tanto antes (pr-tratamento) quanto aps a administrao das substncias-teste (ps-tratamento). A Vit C (1 e 30 mg/Kg) foi administrada apenas no ps-tratamento. O dano no DNA foi avaliado 24 e 48 h aps o incio do tratamento. Aps 24 h, o OJ induziu um suave aumento no dano no DNA, enquanto a Vit C foi genotxica (30 mg/Kg > 1 mg/Kg). O tratamento duplo com Vit C (a 0 e a 24 h) induziu uma resposta genotxica cumulativa a 48 h, que foi mais intensa para a dose maior. O FeSO4 e o CuSO4 foram genotxicos aps 24 h, mas tiveram seu dano efetivamente reparado aps 48 h do tratamento. O pr-tratamento com OJ reduziu a genotoxicidade do FeSO4 e do CuSO4 (efeito preventivo). O ps-tratamento com OJ tambm reduziu a genotoxicidade do CuSO4 (efeito reparador). O OJ mostrou tanto efeito preventivo quanto reparador sobre a genotoxicidade do MMS. O OJ teve apenas efeito reparador sobre a CP. Ambas doses de Vit C aumentaram os danos no DNA causados pelo FeSO4 e pelo CuSO4. processado e armazenado de forma a preservar o seu potencial biolgico um alimento sugerido como uma das pores de uma dieta equilibrada (contendo pelo menos 5 pores de frutas e vegetais), recomendada para uma vida saudvel e longeva.
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Coordenao de Aperfeioamento de Pessoal de Nvel Superior
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Mainstream programming languages provide built-in exception handling mechanisms to support robust and maintainable implementation of exception handling in software systems. Most of these modern languages, such as C#, Ruby, Python and many others, are often claimed to have more appropriated exception handling mechanisms. They reduce programming constraints on exception handling to favor agile changes in the source code. These languages provide what we call maintenance-driven exception handling mechanisms. It is expected that the adoption of these mechanisms improve software maintainability without hindering software robustness. However, there is still little empirical knowledge about the impact that adopting these mechanisms have on software robustness. This work addresses this gap by conducting an empirical study aimed at understanding the relationship between changes in C# programs and their robustness. In particular, we evaluated how changes in the normal and exceptional code were related to exception handling faults. We applied a change impact analysis and a control flow analysis in 100 versions of 16 C# programs. The results showed that: (i) most of the problems hindering software robustness in those programs are caused by changes in the normal code, (ii) many potential faults were introduced even when improving exception handling in C# code, and (iii) faults are often facilitated by the maintenance-driven flexibility of the exception handling mechanism. Moreover, we present a series of change scenarios that decrease the program robustness
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Data clustering is applied to various fields such as data mining, image processing and pattern recognition technique. Clustering algorithms splits a data set into clusters such that elements within the same cluster have a high degree of similarity, while elements belonging to different clusters have a high degree of dissimilarity. The Fuzzy C-Means Algorithm (FCM) is a fuzzy clustering algorithm most used and discussed in the literature. The performance of the FCM is strongly affected by the selection of the initial centers of the clusters. Therefore, the choice of a good set of initial cluster centers is very important for the performance of the algorithm. However, in FCM, the choice of initial centers is made randomly, making it difficult to find a good set. This paper proposes three new methods to obtain initial cluster centers, deterministically, the FCM algorithm, and can also be used in variants of the FCM. In this work these initialization methods were applied in variant ckMeans.With the proposed methods, we intend to obtain a set of initial centers which are close to the real cluster centers. With these new approaches startup if you want to reduce the number of iterations to converge these algorithms and processing time without affecting the quality of the cluster or even improve the quality in some cases. Accordingly, cluster validation indices were used to measure the quality of the clusters obtained by the modified FCM and ckMeans algorithms with the proposed initialization methods when applied to various data sets
