6,977 research outputs found

    Behavior of adherence forces of the butyl mastic and silicone sealant adhesives

    Get PDF
    A pesquisa demonstra como é o comportamento de dois materiais conhecidos comercialmente como mastic em relação às forças de cisalhamento de selantes. No mercado existem dois tipos de mastic, um da família de silicones e outro da borracha butílica. A pesquisa teve o objetivo de esclarecer junto à receita federal e ao mercado, que as propriedades dos dois tipos são muito diferentes, apesar de ambos sofrerem um processo de cura. Com o tempo há aumento das forças de coesão e adesão de ambos, o que evidencia o processo de cura.This study reveals the response to shear forces for two materials known as mastic. There are two kinds of mastic in the market, one of the silicone family and another made with butyl rubber. The aim was to demonstrate to the Inland Revenue and to the market that these materials exhibit very distinct properties, although both undergo the curing process. As time goes by, there is an increase in the forces of cohesion and adhesion for both types of mastic, which is evidence of the curing process

    DNA demethylation caused By 5-Aza-2'-Deoxycytidine induces mitotic alterations and aneuploidy

    Get PDF
    Aneuploidy, the unbalanced number of chromosomes in a cell, is considered a prevalent form of genetic instability and is largely acknowledged as a condition implicated in tumorigenesis. Epigenetic alterations like DNA hypomethylation have been correlated with cancer initiation/progression. Furthermore, a growing body of evidence suggests the involvement of epigenome-wide disruption as a cause of global DNA hypomethylation in aneuploidy generation. Here, we report that the DNA hypomethylating drug 5-aza-2'-deoxycytidine (DAC), affects the correct ploidy of nearly diploid HCT-116 human cells by altering the methylation pattern of the chromosomes. Specifically, we show that a DACinduced reduction of 5-Methyl Cytosine at the pericentromeric region of chromosomes correlates with aneuploidy and mitotic defects. Our results suggest that DNA hypomethylation leads to aneuploidy by altering the DNA methylation landscape at the centromere that is necessary to ensure proper chromosomes segregation by recruiting the proteins necessary to build up a functional kinetochore

    Association Of Nitric Oxide Synthase And Matrix Metalloprotease Single Nucleotide Polymorphisms With Preeclampsia And Its Complications.

    Get PDF
    Preeclampsia is one of the leading causes of maternal and neonatal morbidity and mortality in the world, but its appearance is still unpredictable and its pathophysiology has not been entirely elucidated. Genetic studies have associated single nucleotide polymorphisms in genes encoding nitric oxide synthase and matrix metalloproteases with preeclampsia, but the results are largely inconclusive across different populations. To investigate the association of single nucleotide polymorphisms (SNPs) in NOS3 (G894T, T-786C, and a variable number of tandem repetitions VNTR in intron 4), MMP2 (C-1306T), and MMP9 (C-1562T) genes with preeclampsia in patients from Southeastern Brazil. This prospective case-control study enrolled 77 women with preeclampsia and 266 control pregnant women. Clinical data were collected to assess risk factors and the presence of severe complications, such as eclampsia and HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome. We found a significant association between the single nucleotide polymorphism NOS3 T-786C and preeclampsia, independently from age, height, weight, or the other SNPs studied, and no association was found with the other polymorphisms. Age and history of preeclampsia were also identified as risk factors. The presence of at least one polymorphic allele for NOS3 T-786C was also associated with the occurrence of eclampsia or HELLP syndrome among preeclamptic women. Our data support that the NOS3 T-786C SNP is associated with preeclampsia and the severity of its complications.10e013669

    Early intervention for obsessive compulsive disorder : An expert consensus statement

    Get PDF
    © 2019 Elsevier B.V.and ECNP. All rights reserved.Obsessive-compulsive disorder (OCD) is common, emerges early in life and tends to run a chronic, impairing course. Despite the availability of effective treatments, the duration of untreated illness (DUI) is high (up to around 10 years in adults) and is associated with considerable suffering for the individual and their families. This consensus statement represents the views of an international group of expert clinicians, including child and adult psychiatrists, psychologists and neuroscientists, working both in high and low and middle income countries, as well as those with the experience of living with OCD. The statement draws together evidence from epidemiological, clinical, health economic and brain imaging studies documenting the negative impact associated with treatment delay on clinical outcomes, and supporting the importance of early clinical intervention. It draws parallels between OCD and other disorders for which early intervention is recognized as beneficial, such as psychotic disorders and impulsive-compulsive disorders associated with problematic usage of the Internet, for which early intervention may prevent the development of later addictive disorders. It also generates new heuristics for exploring the brain-based mechanisms moderating the ‘toxic’ effect of an extended DUI in OCD. The statement concludes that there is a global unmet need for early intervention services for OC related disorders to reduce the unnecessary suffering and costly disability associated with under-treatment. New clinical staging models for OCD that may be used to facilitate primary, secondary and tertiary prevention within this context are proposed.Peer reviewe

    Expanding the knowledge on lignocellulolytic and redox enzymes of worker and soldier castes from the lower termite coptotermes gestroi

    Get PDF
    Termites are considered one of the most efficient decomposers of lignocelluloses on Earth due to their ability to produce, along with its microbial symbionts, a repertoire of carbohydrate-active enzymes (CAZymes). Recently, a set of Pro-oxidant, Antioxidant, and Detoxification enzymes (PAD) were also correlated with the metabolism of carbohydrates and lignin in termites. The lower termite Coptotermes gestroi is considered the main urban pest in Brazil, causing damage to wood constructions. Recently, analysis of the enzymatic repertoire of C. gestroi unveiled the presence of different CAZymes. Because the gene profile of CAZy/PAD enzymes endogenously synthesized by C. gestroi and also by their symbiotic protists remains unclear, the aim of this study was to explore the eukaryotic repertoire of these enzymes in worker and soldier castes of C. gestroi. Our findings showed that worker and soldier castes present similar repertoires of CAZy/PAD enzymes, and also confirmed that endo-glucanases (GH9) and beta-glucosidases (GH1) were the most important glycoside hydrolase families related to lignocellulose degradation in both castes. Classical cellulases such as exo-glucanases (GH7) and endo-glucanases (GH5 and GH45), as well as classical xylanases (GH10 and GH11), were found in both castes only taxonomically related to protists, highlighting the importance of symbiosis in C. gestroi. Moreover, our analysis revealed the presence of Auxiliary Activity enzyme families (AAs), which could be related to lignin modifications in termite digestomes. In conclusion, this report expanded the knowledge on genes and proteins related to CAZy/PAD enzymes from worker and soldier castes of lower termites, revealing new potential enzyme candidates for second-generation biofuel processes7CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP140796/2013-4; 310186/2014-5; 442333/2014-511/20977-3; 15/06971-3; 12/19040-0; 14/10351-8; 06/59086-8; 14/20576- 7; 13/03061-0; 10/11469-1; 08/58037-9; 14/50371-8; 08/50114-

    Pre-senescence Harvest of Switchgrass Inhibits Xylose Utilization by Engineered Yeast

    Get PDF
    Proper timing of switchgrass harvest for bioenergy is important to maximize yield and optimize end use conversion. Proposed windows range from peak biomass to the following spring after overwintering in the field. There are various pros and cons associated with harvest timing: earlier harvests maximize yield but can remove nutrients from the field that may require replacement, while later harvests have reduced biomass yields due to weathering but maximize nutrient resorption in belowground tissues. Switchgrass composition changes during the harvest period, with losses of potential fermentation nutrients (amino acids and minerals), and sources of pretreatment-derived inhibitors (soluble sugars), which could affect downstream conversion by microorganisms. For this work we investigated whether switchgrass harvest could be timed to maximize beneficial impacts on fermentation. Switchgrass samples were harvested from five replicate field plots in Wisconsin, roughly every 2–3 weeks from peak biomass (Aug. 20) until after the killing frost (Nov. 7). Cell wall composition showed little consistent variation with harvest date while bulk biomass analysis showed a relative increase in cell wall content (lignin and structural sugars) and loss of extractives (minerals, protein, soluble sugars, and others). Following high or low severity AFEX pretreatment and high solids enzymatic hydrolysis (6% glucan loading), two field replicates were fermented using Saccharomyces cerevisiae 424A, a strain engineered to utilize xylose in addition to glucose. For both pretreatment severities, S. cerevisiae 424A grown in hydrolysates from the three earlier harvests utilized only a small fraction of available xylose, while almost complete utilization occurred within 96 hr for the last three harvest dates. Detailed analysis of the hydrolysate low molecular weight aromatics did not indicate any compounds potentially responsible for the inhibition, with most of the observed variation in their concentration due to pretreatment severity. Amino acid composition also did not appear to be limiting. Current indications point to a plant-generated compound that degrades during senescence, which future work will attempt to identify. Ultimately this work demonstrates that, although an attractive option to maximize yield, harvesting switchgrass before it begins senescing could have a negative effect on downstream conversion processes

    Mudança na expectativa dos pais após receberem o diagnóstico de altas habilidades de seus filhos, na perspectiva de uma especialista em AH/SD / Changes in the expectation of parents after receiving the diagnosis of high skills of their children, from the perspective of an AH / SD specialist

    Get PDF
    Altas habilidades e Superdotação (AH/SD) são caracterizadas por um agrupamento de comportamentos que giram em torno de: habilidades gerais ou especificas acima da média, elevados níveis de comprometimento com a tarefa e elevados níveis de criatividade (Sakaguti, apud Renzulli, 2004). A criança com AH/SD também pode ser identificada por um uso avançado da linguagem, cálculos mentais precoces, elevado interesse em determinadas tarefas e capacidade natural para liderar (Oliveira, 2009). Todavia, durante a história, o foco sempre recaiu sobre o aluno com alguma deficiência intelectual, buscando incentivar suas potencialidades para aprender e se desenvolver como ser humano. Sakaguti (2010) atenta para o fato de não dar importância apenas para o aluno que tem um desenvolvimento aquém do esperado, mas para aquele que está além do esperado, os alunos com altas habilidades/superdotação
    corecore