886 resultados para twin pillars


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Two pillaring methods were tested to synthesize pillared clays containing mixed Al/Co pillars. Using the first method, based on the traditional procedure, were obtained materials containing different Co concentrations: 10, 25, 50, 75 and 100 % of Co in the pillaring solution. Just the experiments with low concentrations (10 and 25 % of Co) has formed pillared clays, whereas the sample with 25 % of cobalt showed best results compared with the one obtained just using Al as pillaring agent (basal spacing higher than 18 Å and surface area bigger than 300 m²/g). The 27Al NMR results pointed out the formation of mixed Al/Co pillars due to decreased between the intensities of AlVI/AlIV signals, indicating that the AlIV content decreased while Co content increased, suggesting the isomorphic substitution of Al atoms for Co in the Keggin ion structure (pillaring agent). For the samples containing 75 and 100 % of cobalt, it was verified the formation of others materials, which could be identified as hydrotalcite like compounds. The second pillarization method was named mixed layers, because the objective was to intercalate clay layers with hydrotalcite layers. Thus, after calcination, the hydrotalcite layers would dehydroxylate, resulting just in the metals oxides, intercalated between the clay sheets, thus generating, a pillared clay. For this purpose, were tested 4 synthesis procedures: physical mixture, mixture in water, ionic exchange under reflux and in situ synthesis. Of these, the method which showed the best results was the in situ synthesis, in which basal spacings of 14 Å (after calcination) were obtained, indicating that the samples are intercalated with metal oxides (Mg and Al). This procedure was reproduced with a Co-Al LDH (layered double hydroxide) and similar results were obtained, testifying the method reproducibility

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This study explores, in 3 steps, how the 3 main library classification systems, the Library of Congress Classification, the Dewey Decimal Classification, and the Universal Decimal Classification, cover human knowledge. First, we mapped the knowledge covered by the 3 systems. We used the 10 Pillars of Knowledge: Map of Human Knowledge, which comprises 10 pillars, as an evaluative model. We mapped all the subject-based classes and subclasses that are part of the first 2 levels of the 3 hierarchical structures. Then, we zoomed into each of the 10 pillars and analyzed how the three systems cover the 10 knowledge domains. Finally, we focused on the 3 library systems. Based on the way each one of them covers the 10 knowledge domains, it is evident that they failed to adequately and systematically present contemporary human knowledge. They are unsystematic and biased, and, at the top 2 levels of the hierarchical structures, they are incomplete.

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OBJETIVO: Avaliar os efeitos do ácido acetilsalicílico a 10% e 20% em linfonodos mesentéricos de coelhos para posterior embasamento e uso em metástases linfonodais. MÉTODOS: Um total de 20 linfonodos de 20 coelhos (divididos aleatoriamente em quatro grupos) foi avaliado. As soluções de aspirina a 10% (grupos A e C) e 20% (grupos B e D) foram injetadas em linfonodos mesentéricos de coelhos sadios e seus efeitos macroscópicos e histológicos foram avaliados em 24 horas (grupos A e B) e em sete dias (grupos C e D). RESULTADOS: Nos grupos avaliados em 24 horas (A e B) foi verificada intensa necrose e hemorragia, aumento importante de apoptose em todo o linfonodo, com alargamento dos seios medulares e aumento dos centros germinativos. Nos grupos avaliados em sete dias (C e D) também houve aumento da apoptose, com maior elevação de histiócitos e diminuição importante da necrose; a hemorragia foi ausente e aumento de células gigantes foi visualizado, conferindo processo inflamatório crônico do tipo corpo estranho. Não houve diferença entre as concentrações utilizadas (10 e 20%) em nenhuma das comparações. CONCLUSÕES: A injeção de aspirina em linfonodos causou necrose e um aumento de apoptose após 24 horas e após sete dias de tratamento, houve regeneração dos gânglios linfáticos, com diminuição intensa de necrose e grande aumento de apoptose. Uma vez que o aumento de apoptose é um dos pilares dos tratamentos antineoplásicos, estes resultados experimentais embasam eventual aplicação clínica da aspirina no tratamento de metástases linfonodais.

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The state has changed over time in order to meet a society with increasingly stringent demands. Techniques of private means begin to be employed in an attempt to overcome the dysfunctions entrenched bureaucracy, making the machine faster. By federal law by the People Management Skills was established as a reference for the administration of Human Resources of the public sector in an attempt to develop professionally servers, based mainly on the three pillars of the model: the knowledge, skills and attitudes. This thesis aims at understanding, in the view of employees, the perceived impacts on the organizational changes occurring in the Department of Administration and Human Resources of the State of Rio Grande do Norte in order to implement a People Management Skills-based. It is a simple case study, characterized by the research during a certain period of time, collecting data in a real environment of an organization, in this case SEARH/RN. The procedures used in collecting data were the literature review, documental research and field research. We used a qualitative approach with exploratory and descriptive approach. Every reform was implemented in the institution and reported from there analyzed the impacts observed by the servers. As a result we observed a considerable advance in institutional activities, mainly relating to physical structure / organizational and human resource policies, with minor advances on labor policies, in much the result of the guiding focus of the reform on SEARH/RN. The impacts in total were more positive than negative and direct paths to improvement in public organizations. Making a general analysis of the modernization program implemented in SEARH/RN, we can conclude that there was a distinct change in all dimensions studied, mostly pointing out positive aspects, and contrary to the opinion of some authors, who claim to be very difficult to implement reforms in public organizations, since they are highly institutionalized environments. What was found was a big organization, with gaps and weaknesses, but with a much larger number of hits and recognition from institutional actors

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The human interference in the semiarid region of Seridó Potiguar has promoted the increase of degraded areas. The economic dynamic that was established in the Seridó territory, especially after the fall of the trinomial cattle-cotton-mining in the 70s and 80s of the 20th century as pillars of the regional economy, resulted in an accelerated process of erosion of natural resources. The municipalities of the Seridó region have been spatially reordered by this new economic dynamic, marked by the growth of existing enterprises, and the development of new agricultural practices. One of the municipalities in the region that restructured its territorial space with the emergence of new agro-industrial activities was the town of Parelhas. With the demise of the trinomial cattle-cotton-mining in the 1980s, other productive activities were intensified from the 1990s, amongst them, pottery, responsible for the vegetal extraction for use as energy source. This recent economic and spatial restructuring in the region, reflected in the Parelhense municipal territory, required new productive ingredients responsible for the modification of past production relations that were based on cattle, cotton and mining. By that a process of exploring the environment was unleashed, especially the native vegetation, in an uncontrolled manner. In this context, the objective of this study was to survey and detect deforestation in the areas of Caatinga vegetation, used indiscriminately as energy supply for new agricultural practices, using remote sensing techniques based on the quantification of the Normalized Difference Vegetation Index / NDVI, Soil-Adjusted Vegetation Index / SAVI, surface temperature and rainfall data in the years 1990 and 2010. The results indicated that SAVI values above 0.2 in 1990 and 2010 represent the areas with the highest density of vegetation that occur exclusively along the major drainages in the town and areas of higher elevations. The areas between the ranges of values from 0.5 to 0.15 SAVI are areas with poor vegetation. On the other hand the highest values of temperature are distributed in the western and southeastern parts of the township, usually in places where the soil is exposed or there is sparse vegetation. The areas of bare soil decreased in extension in 2010 at 11, 6% when related to 1990, this was caused by a higher rainfall intensity in the first half of 2010, but no regeneration of vegetation occurred in some places in the western and southeastern areas of the municipality today, due to the extraction of firewood to fuel the furnaces of industries in town

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Objetivo: estudar as influências da diferença de pesos entre gêmeos, no nascimento, sobre o resultado perinatal. Métodos: analisaram-se, retrospectivamente, as informações referentes aos partos gemelares ocorridos na Maternidade do Hospital Regional de Clínicas de Sorocaba, SP, de julho de 1997 a junho de 1998. A amostragem foi composta de 89 mães e seus gêmeos, divididos em três classes de diferença de pesos ao nascer: com concordância (diferença <15%), discordância leve (de 15 a 25%) e discordância grave (>25%). As variáveis independentes analisadas foram essas três classes e as dependentes foram: baixo peso ao nascer, índice de Apgar menor que 7 no primeiro e quinto minuto, nascimentos pré-termo, tempo médio de internação do recém-nascido no berçário e coeficiente de mortalidade perinatal I. Para análise estatística utilizaram-se o teste de Kruskal-Wallis, complementado pelo teste de Hollander, e o teste de Blackwell. Resultados: a incidência de discordância de pesos entre pares de gêmeos foi de 30,3%, sendo 19,1% de discordância leve e 11,2% de discordância grave. Observamos nas classes, respectivamente, os números de gestações (62, 17 e 10) e de nascimentos pré-termo (32, 9 e 7). Para o primeiro e o segundo gêmeo, observamos: baixo peso ao nascer (39/41, 13/12 e 8/9), Apgar <7 no primeiro minuto (16/13, 3/7 e 2/3), Apgar menor que 7 no quinto minuto (4/4, 0/2 e 1/2), tempo médio (dias) de internação no berçário (3,7/3,7, 4,6/6,0 e 7,3/8,7) e coeficiente de mortalidade perinatal I (22,4/16,8, 0/16,8 e 5,6/5,6). Conclusões: o baixo peso ao nascer e nascimentos pré-termo foram mais freqüentes nos gêmeos da classe com discordância grave. Houve tendência ao agravamento progressivo do resultado perinatal, respectivamente, nas classes com concordância, discordância leve e discordância grave.

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A gravidez gemelar na qual coexistem um feto normal e uma mola completa é um evento raro. Complicações clínicas e aumento de risco de malignização são de importância nesta patologia. Este trabalho descreve um caso de diagnóstico tardio em decorrência da presença do feto. Este diagnóstico foi feito no momento da resolução da gestação e confirmado por estudo histopatológico e citometria de fluxo. A resolução da gestação foi por via transpélvica em decorrência de hemorragia uterina maciça. O seguimento pós-molar evidenciou a persistência de níveis elevados de bhCG, obtendo-se remissão completa da doença com o uso do metotrexato. À luz deste caso, discutem-se o diagnóstico, a história natural e a conduta desta rara intercorrência na clínica obstétrica.

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This research aims to understand the use of the territory from the Rio Grande do Norte to the circuit spatial of production from the Biodiesel understanding it as part of the national context. The introduction of biodiesel into the Brazilian energy matrix begins to take shape in the year 2005 with the implementation of the National Program for Production and Use of Biodiesel (NPPB). This is anchored on three pillars: social inclusion (through family agriculture), environmental sustainability and economic viability. The NPPB consists of a set of standards, which turned into shares and distributed by almost all the national territory. Our reflection assumes that the places accommodating different forms of productive activities and, thus, the performance of the circuit space of biodiesel production depends on several factors, including the configuration of the territory they receive this new nexus economic. Understanding that the places by their technical content determine the realization of productive activities, it was found that the inclusion of this circuit space production in Rio Grande do Norte, reveals the reality expressed in the national territory, where some places are endowed with a privileged technical content and other extremely poor infrastructure. As our research could confirm the circuit space of biodiesel production that is expressed in the way plants are distributed within the country (mostly in South-Central), in more significant participation of small farmers in the South in the supply of raw material for the production of biodiesel and the main raw material used for the production of agrofuels (soybeans, whose production sector is highly consolidated and technified). Already the project materialization of NPPB regarding the settlements and communities of the Rio Grande do Norte State, we observed that the "event" or advent of realization encountered a technical means lacking in infrastructure that need to be molded to the needs of production, or is to cultivate castor beans or sunflower would be needed inputs and implements that farmers don´t have. Given the above, the research concludes that, as proposed previously, the use of the territory of Rio Grande do Norte to this circuit has summarized the performance of experiments, either with regard to the participation of family farmers as suppliers of raw materials, including the development of related research in the stage of production fuel oil by Petrobras. This finding came from research done from the concept of "spatial circuits of production," which allowed the verification of the circuit that steps outlined in Potiguar territory. Regarding the inclusion of family farmers in the productive circuit in RN, research reveals that, in the manner as has been done, it is doomed to failure. Furthermore, we dare say that this persistence in trying to put these family farmers, the way is being made, and the resulting successive failures, indicating that social inclusion advocated by NPPB not take place, and that this production circuit relies on the same logic circuit concentrated and exclusive space for ethanol production

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Background: It has become an accepted procedure to transfer more than one embryo to the patient to achieve acceptable ongoing pregnancy rates. However, transfers of more than a single embryo increase the probability of establishing a multiple gestation. Single-embryo transfer can minimize twin pregnancies but may also lower live birth rates. This meta-analysis aimed to compare current data on single-embryo versus double-embryo transfer in fresh IVF/ICSI cycles with respect to implantation, ongoing pregnancy and live birth rates.Methods: Search strategies included on-line surveys of databases from 1995 to 2008. Data management and analysis were conducted using the Stats Direct statistical software. The fixed-effect model was used for odds ratio (OR). Fixed-effect effectiveness was evaluated by the Mantel Haenszel method. Seven trials fulfilled the inclusion criteria.Results: When pooling results under the fixed-effect model, the implantation rate was not significantly different between double-embryo transfer (34.5%) and single-embryo transfer group (34.7%) (P = 0.96; OR = 0.99, 95% CI 0.78, 1.25). on the other hand, double-embryo transfer produced a statistically significantly higher ongoing clinical pregnancy rate (44.5%) than single-embryo transfer (28.3%) (P < 0.0001; OR: 2.06, 95% CI = 1.64,2.60). At the same time, pooling results presented a significantly higher live birth rate when double-embryo transfer (42.5%) (P < 0.001; OR: 1.87, 95% CI = 1.44,2.42) was compared with single-embryo transfer (28.4%).Conclusion: Meta-analysis with 95% confidence showed that, despite similar implantation rates, fresh double-embryo transfer had a 1.64 to 2.60 times greater ongoing pregnancy rate and 1.44 to 2.42 times greater live birth rate than single-embryo transfer in a population suitable for ART treatment.

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Interferon regulatory factor 6 (IRF6) belongs to a family of nine transcription factors that share a highly conserved helix-turn-helix DNA-binding domain and a less conserved protein-binding domain. Most IRFs regulate the expression of interferon-alpha and -beta after viral infection(1), but the function of IRF6 is unknown. The gene encoding IRF6 is located in the critical region for the Van der Woude syndrome (VWS; OMIM 119300) locus at chromosome 1q32-q41 (refs 2,3). The disorder is an autosomal dominant form of cleft lip and palate with lip pits(4), and is the most common syndromic form of cleft lip or palate. Popliteal pterygium syndrome (PPS; OMIM 119500) is a disorder with a similar orofacial phenotype that also includes skin and genital anomalies(5). Phenotypic overlap(6) and linkage data(7) suggest that these two disorders are allelic. We found a nonsense mutation in IRF6 in the affected twin of a pair of monozygotic twins who were discordant for VWS. Subsequently, we identified mutations in IRF6 in 45 additional unrelated families affected with VWS and distinct mutations in 13 families affected with PPS. Expression analyses showed high levels of Irf6 mRNA along the medial edge of the fusing palate, tooth buds, hair follicles, genitalia and skin. Our observations demonstrate that haploinsufficiency of IRF6 disrupts orofacial development and are consistent with dominant-negative mutations disturbing development of the skin and genitalia.

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Nonsyndromic clefts of the lip and/or palate are common birth defects with a strong genetic component. Based on unequal gender ratios for clefting phenotypes, evidence for linkage to the X chromosome and the occurrence of several X-linked clefting syndromes, we investigated the role of skewed X chromosome inactivation (XCI) in orofacial clefts. Our samples consisted of female monozygotic (MZ) twins (n = 8) and sister pairs (n = 152) discordant for nonsyndromic clefting. We measured the XCI pattern in peripheral blood lymphocyte DNA using a methylation based androgen receptor gene assay. Skewing of XCI was defined as the deviation in inactivation pattern from a 50:50 ratio. Our analysis revealed no significant difference in the degree of skewing between twin pairs (P = 0.3). However, borderline significant differences were observed in the sister pairs (P = 0.02), with the cleft lip with cleft palate group showing the most significant result (P=0.01). We did not find evidence for involvement of skewed XCI in the discordance for clefting in our sample of female MZ twins. However, results from the paired sister study suggest the potential contribution of skewed XCI to orofacial clefting, particularly cleft lip and palate. (C) 2007 Wiley-Liss, Inc.

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Phenotypically discordant monozygotic twins offer the possibility of gene discovery through delineation of molecular abnormalities in one member of the twin pair. One proposed mechanism of discordance is postzygotically occurring genomic alterations resulting from mitotic recombination and other somatic changes. Detection of altered genomic fragments can reveal candidate gene loci that can be verified through additional analyses. We investigated this hypothesis using array comparative genomic hybridization; the 50K and 250K Affymetrix GeneChip (R) SNP arrays and an Illumina custom array consisting of 1,536 SNPs, to scan for genomic alterations in a sample of monozygotic twin pairs with discordant cleft lip and/or palate phenotypes. Paired analysis for deletions, amplifications and loss of heterozygosity, along with sequence verification of SNPs with discordant genotype calls did not reveal any genomic discordance between twin pairs in lymphocyte DNA samples. Our results demonstrate that postzygotic genomic alterations are not a common cause of monozygotic twin discordance for isolated cleft lip and/or palate. However, rare or balanced genomic alterations, tissue-specific events and small aberrations beyond the detection level of our experimental approach cannot be ruled out. The stability of genomes we observed in our study samples also suggests that detection of discordant events in other monozygotic twin pairs would be remarkable and of potential disease significance.

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OBJETIVO: Verificar se as concentrações de glicose e insulina em jejum são reguladas pela aptidão cardiorrespiratória (VO2máx), independentemente dos efeitos genéticos. MÉTODOS: Dados de 38 pares de gêmeos monozigóticos (11 a 18 anos) foram analisados transversalmente. Os participantes foram submetidos a um teste de esforço máximo com ergoespirometria aberta (MedGraphics VO2000® - Medical Graphics Corp., St. Paul, MN) e à coleta de sangue para estimar a concentração de glicose e insulina em jejum. A zigosidade foi determinada por intermédio da investigação de concordância dos gêmeos em relação a 15 marcadores genéticos polimórficos. Nove pares demonstraram diferença média intrapar para o consumo máximo de oxigênio ≥10mL.kg-1.min-1 e foram divididos em dois grupos, de alta e baixa aptidão. Os grupos foram comparados a partir do teste pareado de Wilcoxon, tendo em vista a assimetria dos dados. RESULTADOS: em média, os gêmeos do grupo de alta aptidão apresentaram consumo máximo de oxigênio 17% superior (13,5±3,7mL.kg-1.min-1) a seus irmãos menos aptos. Não houve diferença entre os grupos para as concentrações de insulina (36,5±34,6 versus 25,3±13,7mg/dL; p<0,813), porém, os gêmeos mais aptos demonstraram menor concentração de glicose do que seus contrapares menos aptos (82,9±7,3 versus 86,7±7,6mg/dL; p<0,010). CONCLUSÕES: Neste estudo, caracterizado como caso-controle (gêmeos monozigóticos discordantes), o irmão com menor aptidão cardiorrespiratória apresentou maior concentração de glicose em jejum, sugerindo que a baixa aptidão cardiorrespiratória está associada a distúrbios no metabolismo de glicose.

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In this paper, we consider the symmetric Gaussian and L-Gaussian quadrature rules associated with twin periodic recurrence relations with possible variations in the initial coefficient. We show that the weights of the associated Gaussian quadrature rules can be given as rational functions in terms of the corresponding nodes where the numerators and denominators are polynomials of degree at most 4. We also show that the weights of the associated L-Gaussian quadrature rules can be given as rational functions in terms of the corresponding nodes where the numerators and denominators are polynomials of degree at most 5. Special cases of these quadrature rules are given. Finally, an easy to implement procedure for the evaluation of the nodes is described.

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We ascribe the 15-60 Hz Quasi Periodic Oscillation (QPO) to the periastron precession frequency of the orbiting accreted matter at the boundary of magnetosphere-disk of Xray neutron star (NS). Considering the relativistic motion mechanism for the kHz QPO, that the radii of the inner disk and magnetosphere-disk of NS are correlated with each other by a factor is assumed. The obtained conclusions include: all QPO frequencies increase with increasing the accretion rate. The theoretical relations between 15-60 Hz QPO (HBO) frequency and the twin kHz QPOs are similar to the measured empirical formula. Further, the better fitted NS mass by the proposed model is about 1.9 solar masses for the detected LMXBs.