994 resultados para An Gúm


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Since the successful completion of the cooling storage ring (CSR) project in China at the end of 2007, high qualitative heavy ion beams with energy ranging from keV to GeV/u have been available at the Heavy Ion Research Facility at Lanzhou (HIRFL). More than 10(9) 1 GeVlu C6+ particles or 10(8) 235 MeV/u Xe particles can be stored in the CSR main-ring and extracted within hundred nano-seconds during the test running, the beam parameters will be improved in the coming years so that high energy density (HED) conditions could be achieved and investigated there. Recent scientific results from the experiments relevant to plasma research on HIRFL are summarized. Dense plasma research with intense heavy ion beams of CSR is proposed here.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

National Key Research and Development Program [2010CB833500]; National Natural Science Foundation of China [30590381]; Chinese Academy of Sciences [KZCX2-YW-432]

Relevância:

30.00% 30.00%

Publicador:

Resumo:

National Key Research and Development Program [2010CB833500]; Natural Science Foundation of China [30590381]; Knowledge Innovation Project of Chinese Academy of Sciences [KZCX2-YW-432]

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Anti-neutrophil cytoplasmic antibodies (ANCA) are diagnostic markers for systemic vasculitis. They are classically I detected by an indirect immunofluorescence test using normal donor neutrophils as substrate. This assay lacks antigenic specificity and is not quantitative. The 'EC/BCR Project for ANCA Assay Standardization' is an international collaboration study with the aim to develop and standardize solid phase assays for ANCA detection. In this part of the study the isolation and characterization of proteinase-3 and myeloperoxidase, the two main target molecules for ANCA, and the development and standardization of ELISAs with these antigens are described. Six laboratories successfully isolated purified proteinase-3 preparations that could be used. Three of these preparations, together with one myeloperoxidase preparation, were subsequently used for ANCA testing by ELISA. The ELISA technique was standardized in two rounds of testing in the 14 participating laboratories. The coefficient of variation of these new assays decreased from values of approx. 50% in the first round to approx. 20% in the second round. We conclude that purified proteinase-3 and myeloperoxidase can be used in standardized ELISAs for ANCA detection. Whether such procedures offer advantages over the IIF test will be determined in a prospective clinical study.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

PURPOSE: The endoplasmic reticulum-associated degradation pathway is responsible for the translocation of misfolded proteins across the endoplasmic reticulum membrane into the cytosol for subsequent degradation by the proteasome. To define the phenotype associated with a novel inherited disorder of cytosolic endoplasmic reticulum-associated degradation pathway dysfunction, we studied a series of eight patients with deficiency of N-glycanase 1. METHODS: Whole-genome, whole-exome, or standard Sanger sequencing techniques were employed. Retrospective chart reviews were performed in order to obtain clinical data. RESULTS: All patients had global developmental delay, a movement disorder, and hypotonia. Other common findings included hypolacrima or alacrima (7/8), elevated liver transaminases (6/7), microcephaly (6/8), diminished reflexes (6/8), hepatocyte cytoplasmic storage material or vacuolization (5/6), and seizures (4/8). The nonsense mutation c.1201A>T (p.R401X) was the most common deleterious allele. CONCLUSION: NGLY1 deficiency is a novel autosomal recessive disorder of the endoplasmic reticulum-associated degradation pathway associated with neurological dysfunction, abnormal tear production, and liver disease. The majority of patients detected to date carry a specific nonsense mutation that appears to be associated with severe disease. The phenotypic spectrum is likely to enlarge as cases with a broader range of mutations are detected.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This study presents a methods evaluation and intercalibration of active fluorescence-based measurements of the quantum yield ( inline image) and absorption coefficient ( inline image) of photosystem II (PSII) photochemistry. Measurements of inline image, inline image, and irradiance (E) can be scaled to derive photosynthetic electron transport rates ( inline image), the process that fuels phytoplankton carbon fixation and growth. Bio-optical estimates of inline image and inline image were evaluated using 10 phytoplankton cultures across different pigment groups with varying bio-optical absorption characteristics on six different fast-repetition rate fluorometers that span two different manufacturers and four different models. Culture measurements of inline image and the effective absorption cross section of PSII photochemistry ( inline image, a constituent of inline image) showed a high degree of correspondence across instruments, although some instrument-specific biases are identified. A range of approaches have been used in the literature to estimate inline image and are evaluated here. With the exception of ex situ inline image estimates from paired inline image and PSII reaction center concentration ( inline image) measurements, the accuracy and precision of in situ inline image methodologies are largely determined by the variance of method-specific coefficients. The accuracy and precision of these coefficients are evaluated, compared to literature data, and discussed within a framework of autonomous inline image measurements. This study supports the application of an instrument-specific calibration coefficient ( inline image) that scales minimum fluorescence in the dark ( inline image) to inline image as both the most accurate in situ measurement of inline image, and the methodology best suited for highly resolved autonomous inline image measurements.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The chemokine eotaxin/CCL11 is an important mediator of leukocyte migration, but its effect on inflammatory cytokine signaling has not been explored. In this study, we find that CCL11 induces suppressor of cytokine signaling (SOCS) 1 and SOCS3 expression in murine macrophages, human monocytes, and dendritic cells (DCs). We also discover that CCL11 inhibits GM-CSF-mediated STAT5 activation and IL-4-induced STAT6 activation in a range of hematopoietic cells. This blockade of cytokine signaling by CCL11 results in reduced differentiation and endocytic ability of DCs, implicating CCL11-induced SOCS as mediators of chemotactic inflammatory control. These findings demonstrate cross-talk between chemokine and cytokine responses, suggesting that myeloid cells tracking to the inflammatory site do not differentiate in the presence of this chemokine, revealing another role for SOCS in inflammatory regulation. J. Leukoc. Biol. 85: 289-297; 2009.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The formation of various coatings in molybdenum-boron and molybdenum-silicon systems was investigated. Boronizing and siliciding treatments were conducted in molten salts under inert gas atmosphere in the 850-1050 degrees C temperature range for 7 h. The presence of boride (e.g. Mo2B, MoB, Mo2B5) and silicide (MoSi2, Mo5Si3) phases, formed on the surface of Mo plates, was confirmed by X-ray diffraction analysis. The distribution of elements was determined by means of wavelength dispersive spectroscopy (WDS) spectra of the surface and line-scan analyses from surface to interior. Depending on the process type (diffusional or electrochemical) and temperature, the thickness of the protective layers formed on the substrate ranged from 6 to 40 gm. The oxidation resistance of obtained phases was investigated in an air-water mixture in the temperature range of 500-700 degrees C for a period up to 400 h. An improved oxidation behavior of coated plates in comparison with that of pure molybdenum was observed. (c) 2004 Elsevier B.V. All rights reserved.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Les polymorphonucléaires neutrophiles (PMNs) représentent une arme primordiale dans la défense contre divers agents pathogènes; notamment les bactéries, les champignons, les cellules tumorales de même que les cellules infectées par des virus. Cependant, certaines pathologies reliées à l’inflammation chronique soulèvent l’implication des neutrophiles notamment dans l’arthrite rhumatoïde. La réponse inflammatoire persistante générée par l’activation et la survie des neutrophiles engendre une destruction des tissus environnants suite à la sécrétion non contrôlée de leurs produits cytotoxiques. Même si l’activation chronique des neutrophiles est néfaste dans plusieurs pathologies, elle pourrait s’avérer un bon outil en cas de neutropénie, comme c’est souvent le cas les patients ayant reçu des traitements de chimiothérapie. Ce projet fait suite aux travaux doctoraux de Lagraoui (1999). Il vise à identifier le(s) facteur(s) du liquide synovial qui augmente la survie des neutrophiles ainsi que le mécanisme d’action impliqué dans ce processus. Similairement au facteur semi-pur isolés par Lagraoui (1999), le milieu conditionné concentré (MCC) augmente la survie des PMNs de 75% (39% ± 9.5 vs 68% ± 2.5, p<0.01). Suivant le séquençage du MCC parallèlement au facteur semi-pur actif, deux protéines ont été identifiées à la fois dans le MCC et dans le facteur semi-pur soient : l’albumine et la fétuine. Notre projet vise donc à comparer les effets de l’albumine et de la fétuine à ceux du GM-CSF dans l’optique d’une thérapie alternative au GM-CSF en tant qu’adjuvant de chimiothérapie. La présence d’albumine, de fétuine ou de GM-CSF chez les PMNs incubés 24 heures avec la Mutamycin® induit une diminution du nombre de cellules en apoptose par rapport à la Mutamycin® (Ctrl : 43% ± 10; A : 74% ± 3; F : (82% ± 6 et GM : 74% ± 7; p<0.01). L’effet de l’albumine dépend de la voie de la kinase PI3 mais également celle la kinase ERK, alors que celle de la fétuine dépend de la kinase PI3. Similairement l’EPO, l’albumine et la fétuine supporte la différentiation des HSCs en précurseurs érythrocytaires de type BFU-E. Dans un modèle murin de chiomioprotection, l’albumine augmente la concentration cellulaire rapport au groupe contrôle des leukocytes de la rate (66 ±8 x106c/ml vs 81 ±16 x106c/ml) et du sang (3.6 ±0.4 x106c/ml vs 5.7 ±2.3 x106c/ml). Donc, in vitro, l’albumine et la fétuine sont comparables au GM-CSF au niveau fonctionalité et mécansimes d’action. Cependant, vu leur manque de spécificité, l’application thérapeutique en tant qu’adjuvant de chiomiothérapie de l’albumine et la fétuine est peu prometteuse. Par contre, les maladies dégénératives et les évènements ischémiques pourraient s’avérer de bonnes cibles thérapeutiques, principalement pour l’albumine.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Los sistemas y las tecnologías de información son un elemento vital de las organizaciones exitosas. Por eso constituyen un área esencial de estudio en la administración y dirección de un negocio. Actualmente, la investigación sobre la TI y el desempeño de negocios ha descubierto que cuanto más tenga éxito una empresa para alinear la tecnología de la información con sus objetivos de negocios, mayor será su rentabilidad, y solo una cuarta parte de las empresas logran una alineación entre la TI y los negocios (Luffman, 2003) Esta fuerte tendencia ha tenido un auge interesante en compañías colombianas de todos los tamaños y sectores de la economía; por esta razón hemos buscado abordar una compañía colombiana de talla internacional para describir el proceso de implementación de su sistema de gestión de recursos empresariales (ERP) SAP ECC y su integración dentro de General Motors Colmotores; principalmente con el fin de realizar un análisis del uso que la compañía le está dando a los principales módulos y sub-módulos de contabilidad, ventas y compras de SAP. Este proyecto es muy pertinente especialmente para todos aquellos estudiantes e interesados en el uso y aprovechamiento de los sistemas de información de una compañía, por lo cual se sintetizara la experiencia durante su preparación para la implementación, el desarrollo de la misma y los principales resultados, percibidos por los empleados directamente involucrados, los cuales serán abordados por medio de visitas programadas y entrevistas a profundidad; esto facilitara y permitirá evidenciar de cerca la realidad de la compañía General Motors Colmotores con SAP.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Life-Cycle Assessment (LCA) was used to assess the potential environmental and human health impacts of growing genetically-modified (GM), herbicide-tolerant sugar beet in the UK and Germany compared with conventional sugar beet varieties. The GM variety results in lower potential environmental impacts on global warming, airborne nutrification, ecotoxicity (of soil and water) and watercourse enrichment, and lower potential human health impacts in terms of production of toxic particulates, summer smog, carcinogens and ozone depletion. Although the overall contribution of GM sugar beet to reducing harmful emissions to the environment would be relatively small, the potential for GM crops to reduce pollution from agriculture, including diffuse water pollution, is highlighted.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Cotton production in the European Union (EU) is limited to areas of Greece and Southern Spain (Andalusia). The 2004 reform of the EU cotton policy severely affected the profitability of the crop. In this article we analyze how the introduction of genetically modified (GM), insect-resistant cotton varieties (Bt cotton) might help EU cotton farmers to increase profitability and therefore face the cotton policy reform. We first study farmers’ attitudes toward adoption of Bt cotton varieties through a survey conducted in Andalusia (Southern Spain). The results show a positive attitude of Andalusian cotton farmers toward the Bt cotton varieties. Second, we perform an ex-ante analysis of the effects of introducing Bt cotton in Andalusia. Finally, we integrate the analysis of the effects of Bt cotton with the analysis of the EU cotton reform. Our results show that despite the significant economic benefits of Bt cotton, the current policy reform is likely to jeopardize the profitability of cotton production in the EU.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Data from 60 multiparous Holstein cows were used in a 12-wk continuous design feeding trial. Cows were allocated to 1 of 4 experimental treatments (T1 to T4). In T1 and T2, the total mixed ration (TMR) contained either corn silage from the genetically modified (GM) variety Chardon Liberty Link, which is tolerant to the herbicide glufosinate ammonium, or its near isogenic nonGM counterpart, whereas the TMR used in T3 and T4 contained corn silage from the commercially available nonGM varieties Fabius and Antares, respectively. The objectives of the study were to determine if the inserted gene produced a marked effect on chemical composition, nutritive value, feed intake, and milk production, and to determine if transgenic DNA and the protein expressed by the inserted gene could be detected in bovine milk. The nutritive value, fermentation characteristics, mineral content, and amino acid composition of all 4 silages were similar. There were no significant treatment effects on milk yield, milk composition, and yield of milk constituents, and the dry matter (DM) intake of the GM variety was not significantly different from the 2 commercial varieties. However, although the DM intake noted for the nonGM near-isogenic variety was similar to the commercial varieties, it was significantly lower when compared with the GM variety. Polymerase chain reaction analyses of milk samples collected at wk 1, 6, and 12 of the study showed that none of the 90 milk samples tested positive, above a detection limit of 2.5 ng of total genomic DNA/mL of milk, for either tDNA (event T25) or the single-copy endogenous Zea mays gene, alcohol dehydrogenase. Using ELISA assays, the protein expressed by the T25 gene was not detected in milk.