988 resultados para Site index


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The slow vacuolar (SV) channel has been characterized in different dicots by patch-clamp recordings. This channel represents the major cation conductance of the largest organelle in most plant cells. Studies with the tpc1-2 mutant of the model dicot plant Arabidopsis thaliana identified the SV channel as the product of the TPC1 gene. By contrast, research on rice and wheat TPC1 suggested that the monocot gene encodes a plasma membrane calcium-permeable channel. To explore the site of action of grass TPC1 channels, we expressed OsTPC1 from rice (Oryza sativa) and TaTPC1 from wheat (Triticum aestivum) in the background of the Arabidopsis tpc1-2 mutant. Cross-species tpc1 complementation and patch-clamping of vacuoles using Arabidopsis and rice tpc1 null mutants documented that both monocot TPC1 genes were capable of rescuing the SV channel deficit. Vacuoles from wild-type rice but not the tpc1 loss-of-function mutant harbor SV channels exhibiting the hallmark properties of dicot TPC1/SV channels. When expressed in human embryonic kidney (HEK293) cells OsTPC1 was targeted to Lysotracker-Red-positive organelles. The finding that the rice TPC1, just like those from the model plant Arabidopsis and even animal cells, is localized and active in lyso-vacuolar membranes associates this cation channel species with endomembrane function.

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Crear, dissenyar, implementar i administrar una pàgina web d'una empresa real, utilitzant i aprofintant al màxim les prestacions i funcionalitats que ofereix el gestor de continguts.

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To perform a climatic analysis of the annual UV index (UVI) variations in Catalonia, Spain (northeast of the Iberian Peninsula), a new simple parameterization scheme is presented based on a multilayer radiative transfer model. The parameterization performs fast UVI calculations for a wide range of cloudless and snow-free situations and can be applied anywhere. The following parameters are considered: solar zenith angle, total ozone column, altitude, aerosol optical depth, and single-scattering albedo. A sensitivity analysis is presented to justify this choice with special attention to aerosol information. Comparisons with the base model show good agreement, most of all for the most common cases, giving an absolute error within 0.2 in the UVI for a wide range of cases considered. Two tests are done to show the performance of the parameterization against UVI measurements. One uses data from a high-quality spectroradiometer from Lauder, New Zealand [45.04°S, 169.684°E, 370 m above mean sea level (MSL)], where there is a low presence of aerosols. The other uses data from a Robertson–Berger-type meter from Girona, Spain (41.97°N, 2.82°E, 100 m MSL), where there is more aerosol load and where it has been possible to study the effect of aerosol information on the model versus measurement comparison. The parameterization is applied to a climatic analysis of the annual UVI variation in Catalonia, showing the contributions of solar zenith angle, ozone, and aerosols. High-resolution seasonal maps of typical UV index values in Catalonia are presented

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Rapport de synthèse : But: comparer les taux d'infections du site chirurgical (ISC) en fonction de la voie d'abord, ouverte ou laparoscopique, pour 3 procédures : l'appendicectomie, la cholécystectomie et la colectomie. Evaluer l'effet de la laparoscopie sur l'ISC pour ces trois interventions. Contexte : la laparoscopie est associée à de nombreux avantages par rapport à la chirurgie ouverte. Parmi ceux-ci, des taux inférieurs d'ISC ont été rapportés lors de laparoscopie. Ceci a été décrit en particulier lors de cholécystectomie. Mais des biais tels que le manque de suivi après la sortie de l'hôpital, et certains facteurs confondants, auraient pu contribuer à l'observation de différences entre ces deux techniques. Méthode : étude descriptive basée sur des données collectées entre mars 1998 et décembre 2004 de manière prospective dans le cadre d'un programme de surveillance des ISC dans 8 hôpitaux suisses. Ce programme comportait un suivi standardisé après le départ de l'hôpital. Les taux d'ISC ont été comparés après interventions faites par laparoscopie et chirurgie ouverte. Différents paramètres pouvant influencer la survenue d'une infection ont été identifiés en utilisant des modèles de régression logistiques. Résultats : les taux d'ISC après interventions par laparoscopie et par voie ouverte ont été respectivement de 59/1051 (5.6%) versus 117/1417 (8.3%) après appendicectomie (p = 0.01), 46/2606 (1.7%) versus 35/144 (7.9%) après cholécystectomie (p < 0.0001), et 35/311 (11.3%) versus 400/1781 (22.5%) après colectomie (p < 0,0001). Après ajustement, les interventions par laparoscopie étaient associées à un taux inférieur d'ISC : odds ratio = 0.61 (IC 95% : 0.43 - 0.87) pour l'appendicectomie, 0.27 (0.16 - 0.43) pour la cholécystectomie et 0.43 (0.29 - 0.63) pour la colectomie. Discussion et conclusion : bien que les patients aient quitté plus tôt l'hôpital après une intervention laparoscopique, leur suivi à un mois a été identique, ce qui a permis d'éviter une sous-estimation des ISC après chirurgie laparoscopique. De plus, l'analyse multivariée a inclus de nombreux facteurs potentiellement confondants, et l'utilisation de la laparoscopie était indépendamment et significativement liée à un effet protecteur à l'égard de l'ISC. La laparoscopie lors d'appendicectomie, cholécystectomie et colectomie semble diminuer le taux d'ISC en comparaison à la même chirurgie pratiquée par voie ouverte. Lorsqu'elle est faisable, cette voie d'abord minimalement invasive devrait être préférée à la chirurgie ouverte.

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BACKGROUND: Retinal dystrophies (RD) are a group of hereditary diseases that lead to debilitating visual impairment and are usually transmitted as a Mendelian trait. Pathogenic mutations can occur in any of the 100 or more disease genes identified so far, making molecular diagnosis a rather laborious process. In this work we explored the use of whole exome sequencing (WES) as a tool for identification of RD mutations, with the aim of assessing its applicability in a diagnostic context. METHODOLOGY/PRINCIPAL FINDINGS: We ascertained 12 Spanish families with seemingly recessive RD. All of the index patients underwent mutational pre-screening by chip-based sequence hybridization and resulted to be negative for known RD mutations. With the exception of one pedigree, to simulate a standard diagnostic scenario we processed by WES only the DNA from the index patient of each family, followed by in silico data analysis. We successfully identified causative mutations in patients from 10 different families, which were later verified by Sanger sequencing and co-segregation analyses. Specifically, we detected pathogenic DNA variants (∼50% novel mutations) in the genes RP1, USH2A, CNGB3, NMNAT1, CHM, and ABCA4, responsible for retinitis pigmentosa, Usher syndrome, achromatopsia, Leber congenital amaurosis, choroideremia, or recessive Stargardt/cone-rod dystrophy cases. CONCLUSIONS/SIGNIFICANCE: Despite the absence of genetic information from other family members that could help excluding nonpathogenic DNA variants, we could detect causative mutations in a variety of genes known to represent a wide spectrum of clinical phenotypes in 83% of the patients analyzed. Considering the constant drop in costs for human exome sequencing and the relative simplicity of the analyses made, this technique could represent a valuable tool for molecular diagnostics or genetic research, even in cases for which no genotypes from family members are available.

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The electron hole transfer (HT) properties of DNA are substantially affected by thermal fluctuations of the π stack structure. Depending on the mutual position of neighboring nucleobases, electronic coupling V may change by several orders of magnitude. In the present paper, we report the results of systematic QM/molecular dynamic (MD) calculations of the electronic couplings and on-site energies for the hole transfer. Based on 15 ns MD trajectories for several DNA oligomers, we calculate the average coupling squares 〈 V2 〉 and the energies of basepair triplets X G+ Y and X A+ Y, where X, Y=G, A, T, and C. For each of the 32 systems, 15 000 conformations separated by 1 ps are considered. The three-state generalized Mulliken-Hush method is used to derive electronic couplings for HT between neighboring basepairs. The adiabatic energies and dipole moment matrix elements are computed within the INDO/S method. We compare the rms values of V with the couplings estimated for the idealized B -DNA structure and show that in several important cases the couplings calculated for the idealized B -DNA structure are considerably underestimated. The rms values for intrastrand couplings G-G, A-A, G-A, and A-G are found to be similar, ∼0.07 eV, while the interstrand couplings are quite different. The energies of hole states G+ and A+ in the stack depend on the nature of the neighboring pairs. The X G+ Y are by 0.5 eV more stable than X A+ Y. The thermal fluctuations of the DNA structure facilitate the HT process from guanine to adenine. The tabulated couplings and on-site energies can be used as reference parameters in theoretical and computational studies of HT processes in DNA

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El projecte ha assolit la majoria d’objectius, ajustats a la reducció d'una quarta part de l'import concedit: 1) caracteritzar la transformació del paisatge agro-forestal i urbà a dos municipis de la vall del Congost, La Garriga i Figaró-Montmany, reconstruint amb SIG els mapes d'ús del sòl de 1854, 1949, 1956 i 2005, obtenint per intersecció de cobertes les matrius dels canvis d'ús; i 2) avaluar amb l’índex de connectivitat ecològica l'impacte ambiental d'aquells canvis des del punt de vista de la biodiversitat i la resiliència del paisatges, amb un especial èmfasi en la reforestació induïda per l'abandonament rural i la pèrdua de paisatges en mosaic, en un àmbit més gran pel període 1956-1993-2005. Aquests resultats han permès preparar varis articles per publicar en co-autoría a revistes com Landscape History, Environment and History o Landscape and Urban Planning. Ja és a punt de poder-se lliurar el primer amb el títol de "Looking backwards into a Mediterranean edge environment: Landscape changes and ecological connectivity in El Congost Valley (province of Barcelona, Catalonia) 1850-2005", incloent dos objectius esmentats a la memòria: identificar les principals forces motores d'aquells canvis en el paisatge relacionant els usos del sòl amb les formes d'ordenació del territori, caracteritzar-ne les forces rectores econòmico-socials i el paper jugat per la protecció del Parc Natural del Montseny i els Cingles de Bertí. Els resultats també permetran abordar en el futur altres aspectes, com per exemple estimar el potencial energètic de la biomassa local tot cercant que el seu aprofitament generi sinèrgies territorials positives per a l'ecologia del paisatge amb la recuperació d’una ramaderia extensiva i una agricultura ecològica que facin possible la restauració dels paisatges en mosaic. L'estudi ha pogut incorporar un aspecte inicialment no previst, el cens d'orquídies mediterrànies a Figaró-Montmany elaborat pel naturalista Paul Wilcox

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O uso da tecnologia de informática é uma realidade em todas as áreas do conhecimento humano, nos dias atuais. A incorporação tecnológica se faz nos serviços e no ensino, nos diferentes processos de trabalho do enfermeiro. Este estudo teve como objetivo avaliar um site desenvolvido sobre o tema Escala de Pessoal de Enfermagem, relevante na gestão de recursos humanos em saúde. A metodologia envolveu pesquisa quantitativa com docentes da área de administração em enfermagem, e alunos das oito Universidades Públicas do estado de São Paulo que formam enfermeiros. Entre os principais resultados, apontamos que 85% dos avaliadores consideraram o site excelente ou satisfatório. Além disso, foram analisados os comentários enviados por e-mail e as autoras fazem uma auto-avaliação. O site foi considerado de utilidade tanto para a prática profissional (81,7% entre excelente e satisfatório) como para o ensino (84,6% entre excelente e satisfatório).

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The article presents and discusses estimates of social and economic indicators for Italy’s regions in benchmark years roughly from Unification to the present day: life expectancy, education, GDP per capita at purchasing power parity, and the new Human Development Index (HDI). A broad interpretative hypothesis, based on the distinction between passive and active modernization, is proposed to account for the evolution of regional imbalances over the long-run. In the lack of active modernization, Southern Italy converged thanks to passive modernization, i.e., State intervention: however, this was more effective in life expectancy, less successful in education, expensive and as a whole ineffective in GDP. As a consequence, convergence in the HDI occurred from the late XIX century to the 1970s, but came to a sudden halt in the last decades of the XX century.

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Une classification simplifiee du genre Colaniella LIKHAREV est proposee: Colaniella ex gr. parva, Colaniella ex gr. lepida, Colaniella ex gr. minima. Elle correspond a la division du taxon en trois groupes morphologiques. La repartition geographique de ce taxon est inventoriée de meme que les environnements sedimentaires et les microfaunes associees. Les nouvelles decouvertes de C. ex gr. parva dans Ie Permien superieur des coupes de Mesagros (ile d'Egine, Grece), d'Emarat (N Elbourz, Iran) et du Wadi Wasil dans les montagnes centrales d'Oman sont decrites en detail. L'importance des Colanielles dans la biostratigraphie du Permien superieur tethysien est analysee et clarifiee au vu des travaux recents et Ie problème des migrations est abordé. A simplified taxonomic classification in 3 groups of the genus Colaniella LIKHAREV is proposed: Colaniella ex gr. parva, Colaniella ex gr. lepida, Colaniella ex gr. minima. The repartition of the eight main Colaniella biofacies is given and the paleogeographic distribution of this genus is presented on a late Permian map configuration. New late Permian localities with Colaniella ex gr. parva have been found: Aegina island (Greece), Emmarat in the northern Alborz (Iran) and Wadi Wasit in the central Oman Mountains. The stratigraphic range of Colaniella ex gr. parva is much longer than previously accepted even by specialists. This range begins in the early Midian (Abadehian) and ends in the late Changhsingian (Dorashamian), very close to the range of the genus. For environmental reasons and slow eastward migration we have apparent shorter ranges in the Eastern part of the Tethyan domain.

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BACKGROUND: Cigarette smoking is associated with lower body mass index (BMI), and a commonly cited reason for unwillingness to quit smoking is a concern about weight gain. Common variation in the CHRNA5-CHRNA3-CHRNB4 gene region (chromosome 15q25) is robustly associated with smoking quantity in smokers, but its association with BMI is unknown. We hypothesized that genotype would accurately reflect smoking exposure and that, if smoking were causally related to weight, it would be associated with BMI in smokers, but not in never smokers. METHODS: We stratified nine European study samples by smoking status and, in each stratum, analysed the association between genotype of the 15q25 SNP, rs1051730, and BMI. We meta-analysed the results (n = 24 198) and then tested for a genotype × smoking status interaction. RESULTS: There was no evidence of association between BMI and genotype in the never smokers {difference per T-allele: 0.05 kg/m(2) [95% confidence interval (95% CI): -0.05 to 0.18]; P = 0.25}. However, in ever smokers, each additional smoking-related T-allele was associated with a 0.23 kg/m(2) (95% CI: 0.13-0.31) lower BMI (P = 8 × 10(-6)). The effect size was larger in current [0.33 kg/m(2) lower BMI per T-allele (95% CI: 0.18-0.48); P = 6 × 10(-5)], than in former smokers [0.16 kg/m(2) (95% CI: 0.03-0.29); P = 0.01]. There was strong evidence of genotype × smoking interaction (P = 0.0001). CONCLUSIONS: Smoking status modifies the association between the 15q25 variant and BMI, which strengthens evidence that smoking exposure is causally associated with reduced BMI. Smoking cessation initiatives might be more successful if they include support to maintain a healthy BMI.

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CodeML (part of the PAML package) im- plements a maximum likelihood-based approach to de- tect positive selection on a specific branch of a given phylogenetic tree. While CodeML is widely used, it is very compute-intensive. We present SlimCodeML, an optimized version of CodeML for the branch-site model. Our performance analysis shows that SlimCodeML substantially outperforms CodeML (up to 9.38 times faster), especially for large-scale genomic analyses.