1000 resultados para 128-799C


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Foram feitas determinações de zinco total, solúvel em HCl 0,1 N, solúvel em EDTA-(NH4) 2CO3 e solúvel em ditizona em 8 perfis de solos de 8 séries de solos do município de Piracicaba, Estado de São Paulo-Brasil. Para determinação do zinco total, solúvel em HCl 0,1 N, solúvel em EDTA(NH4/2CO3 e solúvel em ditizona, usouse o método de TRIERWEILER e LINDSAY (1968) e para a ditizona (NH4/2SO4 o método de SHAW e DEAN (1952). Foram estudadas as correlações entre as soluções extratoras de zinco e o zinco total, e o confronto entre os extratores químicos. A solução extratora de HCl 0,1 N extraiu maior quantidade de zinco do que as soluções do EDTA-carbonato de amônio e de ditizona acetato de amônio. Esta, por sua vez, na maior parte dos casos, não diferiu da solução do EDTA-carbonato de amônio. Estudo de correlações entre as soluções extratoras e o zinco total mostrou que apenas o HCl 0,1 N apresentou tal correlação. As principais conclusões foram as seguintes: 1- Os teores de zinco total para os perfis de solos situam-se entre 23 e 128 ppm de Zn. 2- As séries Bairrinho, Luiz de Queiroz e Guamium foram as mais altas em Zn total (46 a 128 ppm). 3- As séries Paredão Vermelho, Quebra Dente, Monte Olimpo e Lageadinho foram as mais baixas em zinco total (23 a 55 ppm de Zn). 4- O HCl 0,1 N extraiu mais zinco do que as soluções de EDTA- (NH4) 2CO3 e da ditizona e acetato de amônio. Entre estas duas soluções não houve diferença nos teores. 5- Os solos Luiz de Queiroz, Lageadinho e Bairrinho, foram os altos em zinco solúvel, pelas soluções extratoras.

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Este estudo explora a maturação de gametas e biometria de Phragmatopoma caudata Krøyer in Mörch, 1863 para endossar uma metodologia e oferecer uma técnica adequada para estudos que objetivam avaliar a ecologia populacional. A análise de correlação de Pearson confirmou a relação positiva (r = 0,90, P <0,0001) entre o comprimento do corpo e o comprimento da coroa opercular. Indivíduos com opercular crown < 0,9 mm podem ser considerados como juvenil devido à ausência de gametas. Portanto, utilizando-se o método aprovado para separar as classes de tamanho, a população dos recifes de P. caudata no Parque Estadual Xixová-Japuí (PEJX) na Baía de Santos, Estado de São Paulo, foi examinada durante dois anos, com o objetivo de analisar a densidade populacional e o padrão sazonal da classe juvenil. Em período de elevadas taxas de juvenis, a densidade populacional atingiu 128.115 ind./m², porém, a média foi 65.090±22.033 ind./m². As análises estatísticas (Kruskal-Wallis H = 18,475, p < 0,01) revelaram existir variação significativa na composição juvenil entre as estações chuvosa e seca. Apesar da presença de juvenis em meses de seca, as estações chuvosas contemplaram 92,1% dos juvenis amostrados. O padrão de juvenis observado pode estar relacionado com fatores biológicos (e.g. gametogênese e ciclo de vida) e abióticos (e.g. suprimento alimentar e correntes marinhas). Estes resultados destacam a necessidade de programas de monitoramento de longo prazo que integrem elementos ecológicos e abióticos, a fim de obter uma compreensão mais completa da ecologia desse poliqueta e ajudar a gerenciar a biodiversidade marinha do PEJX.

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Durant els darrers anys, s’han publicat un gran nombre de materials multimèdia destinats a l’aprenentatge de llengües, la major part dels quals son CD-ROM dissenyats com a cursos per l’autoaprenentatge. Amb aquests materials, els alumnes poden treballar independentment sense l’assessorament d’un professor, i per aquest motiu s’ha afirmat que promouen i faciliten l’aprenentatge autònom. Aquesta relació, però, no es certa, com Phil Benson i Peter Voller 1997:10) han manifestat encertadament:(…) Such claims are often dubious, however, because of the limited range of options and roles offered to the learner. Nevertheless, technologies of education in the broadest sense can be considered to be either more or less supportive of autonomy. The question is what kind of criteria do we apply in evaluating them? En aquest article presentem una investigació conjunta on es defineixen els criteris que poden ser utilitzats per avaluar materials multimèdia en relació a la seva facilitat per permetre l’aprenentatge autònom. Aquests criteris son la base d’un qüestionari que s’ha emprat per avaluar una selecció de CD-ROM destinats a l’autoaprenentatge de llengües. La estructura d’aquest article és la següent: - Una introducció de l’estudi - Els criteris que s’han utilitzar per la creació del qüestionari - Els resultats generals de l’avaluació - Les conclusions que s’han extret i la seva importància pel disseny instructiu multimèdia

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MFA Thesis Exhibition February 7-11, 2011, Peggy Phelps Gallery, Claremont Graduate University.

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Desde el área de Ingeniería de RF del consorcio CELLS y en el marco de un convenio de colaboración firmado con el grupo de antenas y sistemas de microondas del Departamento de Telecomunicación e Ingeniería de sistemas de la ETSE (UAB), se ha planteado la evaluación y construcción de un filtro que formará parte del lazo de control en el módulo de RF. El objetivo es eliminar una señal espuria que se encuentra a la salida de un mezclador en banda lateral única, que por limitaciones en los inbalanceos de ganancia y fase, no termina de cancelar suficientemente la banda rechazada. Por lo tanto, el trabajo surge de la necesidad de diseñar un filtro capaz de obtener una respuesta paso banda centrada a 520 MHz, para atenuar un espurio existente a una frecuencia cercana (530 MHz). En consecuencia, estas especificaciones proporcionarán al filtro la característica de banda estrecha.

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Background/Purpose: The trabecular bone score (TBS), a novel graylevel texture index determined from lumbar spine DXA scans, correlates with 3D parameters of trabecular bone microarchitecture known to predict fracture. TBS may enhance the identification of patients at increased risk for vertebral fracture independently of bone mineral density (BMD) (Boutroy JBMR 2010; Hans JBMR 2011). Denosumab treatment for 36 months decreased bone turnover, increased BMD, and reduced new vertebral fractures in postmenopausal women with osteoporosis (Cummings NEJM 2009). We explored the effect of denosumab on TBS over 36 months and evaluated the association between TBS and lumbar spine BMD in women who had DXA scans obtained from eligible scanners for TBS evaluation in FREEDOM. Methods: FREEDOM was a 3-year, randomized, double-blind trial that enrolled postmenopausal women with a lumbar spine or total hip DXA T-score __2.5, but not __4.0 at both sites. Women received placebo or 60 mg denosumab every 6 months. A subset of women in FREEDOM participated in a DXA substudy where lumbar spine DXA scans were obtained at baseline and months 1, 6, 12, 24, and 36. We retrospectively applied, in a blinded-to-treatment manner, a novel software program (TBS iNsightR v1.9, Med-Imaps, Pessac, France) to the standard lumbar spine DXA scans obtained in these women to determine their TBS indices at baseline and months 12, 24, and 36. From previous studies, a TBS _1.35 is considered as normal microarchitecture, a TBS between 1.35 and _1.20 as partially deteriorated, and 1.20 reflects degraded microarchitecture. Results: There were 285 women (128 placebo, 157 denosumab) with a TBS value at baseline and _1 post-baseline visit. Their mean age was 73, their mean lumbar spine BMD T-score was _2.79, and their mean lumbar spine TBS was 1.20. In addition to the robust gains in DXA lumbar spine BMD observed with denosumab (9.8% at month 36), there were consistent, progressive, and significant increases in TBS compared with placebo and baseline (Table & Figure). BMD explained a very small fraction of the variance in TBS at baseline (r2_0.07). In addition, the variance in the TBS change was largely unrelated to BMD change, whether expressed in absolute or percentage changes, regardless of treatment, throughout the study (all r2_0.06); indicating that TBS provides distinct information, independently of BMD. Conclusion: In postmenopausal women with osteoporosis, denosumab significantly improved TBS, an index of lumbar spine trabecular microarchitecture, independently of BMD.

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In the present study, we evaluated stimulation of the angiotensin type 2 receptor (AT2R) by the selective non-peptide agonist Compound 21 (C21) as a novel therapeutic concept for the treatment of multiple sclerosis using the model of experimental autoimmune encephalomyelitis (EAE) in mice. C57BL-6 mice were immunized with myelin-oligodendrocyte peptide and treated for 4 weeks with C21 (0.3 mg/kg/day i.p.). Potential effects on myelination, microglia and T-cell composition were estimated by immunostaining and FACS analyses of lumbar spinal cords. The in vivo study was complemented by experiments in aggregating brain cell cultures and microglia in vitro. In the EAE model, treatment with C21 ameliorated microglia activation and decreased the number of total T-cells and CD4+ T-cells in the spinal cord. Fluorescent myelin staining of spinal cords further revealed a significant reduction in EAE-induced demyelinated areas in lumbar spinal cord tissue after AT2R stimulation. C21-treated mice had a significantly better neurological score than vehicle-treated controls. In aggregating brain cell cultures challenged with lipopolysaccharide (LPS) plus interferon-γ (IFNγ), AT2R stimulation prevented demyelination, accelerated re-myelination and reduced the number of microglia. Cytokine synthesis and nitric oxide production by microglia in vitro were significantly reduced after C21 treatment. These results suggest that AT2R stimulation protects the myelin sheaths in autoimmune central nervous system inflammation by inhibiting the T-cell response and microglia activation. Our findings identify the AT2R as a potential new pharmacological target for demyelinating diseases such as multiple sclerosis.

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Complete achromatopsia is a rare autosomal recessive disease associated with CNGA3, CNGB3, GNAT2 and PDE6C mutations. This retinal disorder is characterized by complete loss of color discrimination due to the absence or alteration of the cones function. The purpose of the present study was the clinical and the genetic characterization of achromatopsia in a large consanguineous Tunisian family. Ophthalmic evaluation included a full clinical examination, color vision testing and electroretinography. Linkage analysis using microsatellite markers flanking CNGA3, CNGB3, GNAT2 and PDE6C genes was performed. Mutations were screened by direct sequencing. A total of 12 individuals were diagnosed with congenital complete achromatopsia. They are members of six nuclear consanguineous families belonging to the same large consanguineous family. Linkage analysis revealed linkage to GNAT2. Mutational screening of GNAT2 revealed three intronic variations c.119-69G>C, c.161+66A>T and c.875-31G>C that co-segregated with a novel mutation p.R313X. An identical GNAT2 haplotype segregating with this mutation was identified, indicating a founder mutation. All patients were homozygous for the p.R313X mutation. This is the first report of the clinical and genetic investigation of complete achromatopsia in North Africa and the largest family with recessive achromatopsia involving GNAT2; thus, providing a unique opportunity for genotype-phenotype correlation for this extremely rare condition.

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Se estudia el Ensayo Inmunoenzimático en Microgotas sobre Nitrocelulosa (Dot-ELISA)comparando dos preparados antigénicos de formas epimastigotas de cultivo de T. cruzi: 1) la fracción citoplasmática (antígeno citoplasmático y 2) el parásito total fijado previamente con formaldehido (antígeno integral). Se usaron sueros de: 95 pacientes chagásicos con serología convencional positiva, cardiopatía crónica y algunos con xenodiagnóstico positivo; 42 personas sanas y 32 con miocardipatía crónica con serología negativa y 74 pacientes con diferentes patologías incluyendo: sífilis, toxoplasmosis, lupus eritematoso diseminado, con factor reumatoide, leishmaniasis visceral, y leishmaniasis cutánea. Definidos los títulos diagnósticos (cut-off) de 1:512 con antígeno citoplasmático y de 1: 128 con antígeno integral, la especificidad fue 96% para el primero y de 100% para el segundo; mientras que la sensibilidad fue de 100% para ambas. En el estudio comparativo con las pruebas serológicas convencionales examinando 147 sueros tomados de personas referidas al laboratório, Dot-ELISA con antígeno citoplasmático presentó índices deco-positividad de 1,0, co-negatividad de 0,989 y eficiencia 0,993. Dot-ELIS con antígeno integral dió 1,0, 0,979 y 0,986 respectivamente. De acuerdo con esta evaluación, la técnica Dot-ELISA con antígeno integral se presenta como una alternativa práctica para el diagnóstico serológico de la enfermedad de Chagas.

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L'ubiquitination est une modification des protéines conservée, consistant en l'addition de résidus « ubiquitine » et régulant le destin cellulaire des protéines. La protéine « TRAF-interacting protein » TRAIP (ou TRIP) est une ligase E3 qui catalyse l'étape finale de l'ubiquitination. TRAIP est conservé dans l'évolution et est nécessaire au développement des organismes puisque l'ablation de TRAIP conduit à la mort embryonnaire aussi bien de la drosophile que de la souris. De plus, la réduction de l'expression de TRAIP dans des kératinocytes épidermiques humains réprime la prolifération cellulaire et induit un arrêt du cycle cellulaire en phase Gl, soulignant le lien étroit entre TRAIP et la prolifération cellulaire. Comme les mécanismes de régulation de la prolifération jouent un rôle majeur dans l'homéostasie de la peau, il est important de caractériser la fonction de TRAIP dans ces mécanismes. En utilisant des approches in vitro, nous avons déterminé que la protéine TRAIP est instable, modifiée par l'addition d'ubiquitine et ayant une demi-vie d'environ 4 heures. Nos analyses ont également révélé que l'expression de TRAIP est dépendante du cycle cellulaire, atteignant un pic d'expression en phase G2/M et que l'induction de son expression s'effectue principalement au cours de la transition Gl/S. Nous avons identifié le facteur de transcription E2F1 comme en étant le responsable, en régulant directement le promoteur de TRAIP. Aussi, TRAIP endogène ou surexprimée est surtout localisée au niveau du nucléole, une organelle nucléaire qui est désassemblée pendant la division cellulaire. Pour examiner la localisation subcellulaire de TRAIP pendant la mitose, nous avons imagé la protéine TRAIP fusionnée à une protéine fluorescente, à l'intérieur de cellules vivantes nommées HeLa, à l'aide d'un microscope confocal. Dans ces conditions, TRAIP est majoritairement localisée autour des chromosomes en début de mitose, puis est arrangée au niveau de l'ADN chromosomique en fin de mitose. La détection de TRAIP endogène à l'aide d'un anticorps spécifique a confirmé cette localisation. Enfin, l'inactivation de TRAIP dans les cellules HeLa par interférence ARN a inhibé leur capacité à s'arrêter en milieu de mitose. Nos résultats suggèrent que le mécanisme sous-jacent peut être lié au point de contrôle de l'assemblage du fuseau mitotique. - Ubiquitination of proteins is a post-translational modification which decides the cellular fate of the protein. The TRAF-interacting protein (TRAIP, TRIP) functions as an E3 ubiquitin ligase mediating addition of ubiquitin moieties to proteins. TRAIP interacts with the deubiquitinase CYLD, a tumor suppressor whose functional inactivation leads to skin appendage tumors. TRAIP is required for early embryonic development since removal of TRAIP either in Drosophila or mice by mutations or knock¬out is lethal due to aberrant regulation of cell proliferation and apoptosis. Furthermore, shRNA- mediated knock-down of TRAIP in human epidermal keratinocytes (HEK) repressed cell proliferation and induced a Gl/S phase block in the cell cycle. Additionally, TRAIP expression is strongly down- regulated during keratinocyte differentiation supporting the notion of a tight link between TRAIP and cell proliferation. We thus examined the biological functions of TRAIP in epithelial cell proliferation. Using an in vitro approach, we could determine that the TRAIP protein is unstable, modified by addition of ubiquitin moieties after translation and exhibits a half-life of 3.7+/-1-6 hours. Our analysis revealed that the TRAIP expression is modulated in a cell-cycle dependent manner, reaching a maximum expression level in G2/M phases. In addition, the expression of TRAIP was particularly activated during Gl/S phase transition and we could identify the transcription factor E2F1 as an activator of the TRAIP gene promoter. Both endogenous and over-expressed TRAIP mainly localized to the nucleolus, a nuclear organelle which is disassembled during cell division. To examine the subcellular localization of TRAIP during M phase, we performed confocal live-cell imaging of a functional fluorescent protein TRAIP-GFP in HeLa cells. TRAIP was distributed in the cytoplasm and accumulated around mitotic chromosomes in pro- and meta-phasic cells. TRAIP was then confined to chromosomal DNA location in anaphase and later phases of mitosis. Immune-detection of endogenous TRAIP protein confirmed its particular localization in mitosis. Finally, inactivating TRAIP expression in HeLa cells using RNA interference abrogated the cells ability to stop or delay mitosis progression. Our results suggested that TRAIP may involve the spindle assembly checkpoint.

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In this paper we use an energy-economy-environment computable general equilibrium (CGE) model of the Scottish economy to examine the impacts of an exogenous increase in energy augmenting technological progress in the domestic commercial Transport sector on the supply and use of energy. We focus our analysis on oil, as the main type of energy input used in commercial transport activity. We find that a 5% increase in energy efficiency in the commercial Transport sector leads to rebound effects in the use of oil-based energy commodities in all time periods, in the target sector and at the economy-wide level. However, our results also suggest that such an efficiency improvement may cause a contraction in capacity in the Scottish oil supply sector. This ‘disinvestment effect’ acts as a constraint on the size of rebound effects. However, the magnitude of rebound effects and presence of the disinvestment effect in the simulations conducted here are sensitive to the specification of key elasticities of substitution in the nested production function for the target sector, particularly the substitutability of energy for non-energy intermediate inputs to production.

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El projecte exposat té com a propòsit definir i implementar un model de simulació basat en la coordinació i assignació dels serveis d’emergència en accidents de trànsit. La definició del model s’ha realitzat amb l’ús de les Xarxes de Petri Acolorides i la implementació amb el software Rockwell Arena 7.0. El modelatge de la primera simulació ens mostra un model teòric basat en cues mentre que el segon, mostra un model més complet i real gràcies a la connexió mitjançant la plataforma Corba a una base de dades amb informació geogràfica de les flotes i de les rutes. Com a resultat de l’estudi i amb l’ajuda de GoogleEarth, podem realitzar simulacions gràfiques per veure els accidents generats, les flotes dels serveis i el moviment dels vehicles des de les bases fins als accidents.

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The murine model of chronic Chaga's myocardiopathy was developed in 201 inbred and outbred mice. The experimental groups consisted of 1st: 73 inbred AKR and A/J mice inoculated with one of the following. Trypanosoma cruzi strains: Peruvian (Type I), 12 SF (Type II) or Colombian (Type III); 2nd: 128 outbred Swiss mice, chronically infected either with Type II or Type III strains isolated from human patients from different geographical areas. All T. cruzi strains were previoulsly characterized by their morphobiological behaviour in mice and by isoenzymatic patterns. For the 1st group the inoculum was 5 x 10**4 for the Peruvian strain and 1 x 10**5 for the 12 SF and Colombian strains. In the 2nd group-Swiss mice the inoculum size varied from 2 x 10**4 to 2 x 10**5. The inbred animals were killed at a 3 time-point scale (90, 180 and 240 days) post-infection. The Swiss mice were killed from 180 to 660 days after infection. The evaluation of parasitemia and serology (xeodiagnosis and indirect immunofluorescent test) was performed. The incidence of macroscopic alterations of the heart and cardiac index were evaluated. Histopathological lesions of the myocardium were graded. The influence of T. cruzi strain on the intensity of cardiac lesions was evaluated by the Chi-square test; the incidence of inflammatory lesions and its relationship to the parasite strain was evaluated by the Fisher test. The influence of the duration of infection was evaluated by using the Gamma Coefficient of Kruskal and Goodman and its measure of significance. Slight to severe microscopic alterations occurred in 85% of the chronically infected nice. There were a clear predominance on the incidence and intensity of inflammatory and fibrotic alterations for the mice infected with Type III strains. Statistical analysis has shown significant differences among the infected groups, in the inflammatory and fibrotic lesions. Macroscopic alterations (right cavities dilatation and apex aneurism of left ventricle), differed in incidence according to mice strains; in Swiss and AKR mice, significant differences were seen in mice infected with different T. cruzi strains, but the A/J mice failed to show significant differences correlated with different parasite strains. The duration of infection, from 90 to 240 days, could not be correlated with the degree of lesions in the several groups.