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Social capital and self-rated health among adolescents in Brazil: an exploratory study
<p>Abstract</p> <p>Background</p> <p>Social capital may influence health and the patterns of association differ according its dimension such as cognitive, behavioral, bridging or bonding. There is a few numbers of studies in Latin America which comprise these aspects of social capital and health. The aim of this study was to examine the association between social capital and self-rated health among youth, and distinguish between the different forms of social capital - cognitive versus behavioral, and bonding versus bridging.</p> <p>Findings</p> <p>A cross-sectional study was conducted in 2009 among working adolescents supported by a Brazilian NGO. The sample comprised 363 individuals and data were collected using a validated structured questionnaire. The outcome, self-rated health, was measured as a dichotomous variable (poor/good health) and fourteen social capital indicators were investigated (cognitive, behavioral and bonding/bridging). Data were analyzed using multivariate logistic regression. Cognitive (social support and trust), behavioral (civic participation) and bridging social capital were associated with good self-rated health after adjustment of all the other social capital indicators and confounders (sex, age, skin color and educational background).</p> <p>Conclusions</p> <p>Social capital was associated with self-rated health and the patterns of association differed according its specific dimensions. Cognitive, behavioral and bridging social capitals were protective for adolescents health living in a developing country context..</p
Glyphosate translocation in herbicide tolerant plants.
The objective of this study was to evaluate glyphosate translocation in glyphosate-tolerant weed species (I.nil, T.procumbens and S.latifolia) compared to glyphosate-susceptible species (B. pilosa). The evaluations of 14 C-glyphosate absorption and translocation were performed at 6, 12, 36 and 72 hours after treatment (HAT) in I. nil and B. pilosa, and only at 72 HAT in the species T. procumbens and S. latifolia. The plants were collected and fractionated into application leaf, other leaves, stems, and roots. In S. latifolia, approximately 88% of the glyphosate remained in the application leaf and a small amount was translocated to roots at 72 HAT. However, 75% of the herbicide applied on T. procumbens remained in the leaf that had received the treatment, with greater glyphosate translocation to the floral bud. It was concluded that the smaller amount of glyphosate observed in S. latifolia and T. procumbens may partly account for their higher tolerance to glyphosate. However, I.nil tolerance to glyphosate may be associated with other factors such as metabolization, root exudation or compartmentalization, because a large amount of the herbicide reached the roots of this species
Slurry preparation methods affect dental porcelain reliability
One-step and incremental mixing procedures are currently used to produce dental ceramic pastes. In the ceramic industry, high quality is obtained using
one-step mixing, but in dentistry, the best method has not been yet determined.
The purpose of this study is to evaluate the effects of 2 mixing techniques on the biaxial flexural strength and microstructure of dental porcelain.
Feldspathic porcelain discs (2 × 15 mm in diameter) were produced and divided according to the ceramic paste preparation method, powder-liquid incremental
mixing group (n=50) or one-step mixing, as a control group (n=50). Specimens were tested for biaxial flexural strength and characterized using porosimetry,
relative humidity, SEM/EDS, XRD, and FT-IR analyses. Statistical analysis was conducted using Weibull statistics. The Weibull modulus, characteristic strength
and relative humidity were compared between groups, using Student's t-test and Mann-Whitney U test (a=.05).
The powder-liquid incremental mixing group showed significantly higher values (SD) of Weibull modulus (6.74 (0.70), P<.001) and characteristic strength
(79.87 (2.01) MPa, P<.001) when compared to the one-step mixing group (4.94 (0.94) and 75.95 (2.61) MPa). Significantly lower mean (SD) relative humidity
values (P=.009) were found for powder-liquid incremental mixing group (20% (0.5%)) compared to one-step mixing group (22% (1%)). XRD spectra showed
that the one-step mixing group produced higher amounts of the amorphous phase.
Specimens produced by the incremental mixing technique showed higher biaxial flexural strength than one-step mixing
DEVELOPMENT OF AN AIR HEATING AND HUMIDIFYING SYSTEM FOR MECHANICAL VENTILATION OF INTENSIVE CARE UNIT PATIENTS
The mechanical ventilators, also named artificial ventilators, are devices used in Intensive Care Units (ICU) for clinically critical patients. The equipment provides artificial breathing for the patient, creating favorable conditions for the patient recovery. It works as a system that is connected to the electric grid and two other networks, one supplies compressed air and the other supplies pure oxygen. Inside the equipment the gases are mixed, and then warmed up and humidified to be finally delivered to the patient. The existing system for treatment of the mixture is not effective, since it delivers the breathing air to the patient out of the normal physiology recommended range, i.e., temperature ~32-34°C and relative humidity ~80-95%. The objective of this work was to develop a new air heating and humidifying system for mechanical ventilation. First, it was built an air feeding system, composed by a compressor and an electronically controlled valve to simulate an actual mechanical ventilation system in the laboratory. A device for conditioning the air (temperature and humidity) was conceived and built for treating the air feeding system output air. The results of the laboratory measurements show that the developed equipment was capable of making the breathing air to reach the recommended ranges by the normal physiology
Accuracy of the Simplified Thylstrup & Fejerskov Index in Rural Communities with Endemic Fluorosis
The aim of the present study was to compare the values of the Thylstrup & Fejerskov Index (TF index) for the determination of the prevalence of dental fluorosis using either all teeth (gold standard) or six upper anterior teeth (simplified TF index). The sample was made up of 396 individuals aged six to 22 years from three Brazilian cities with endemic fluorosis caused by the ingestion of water with high fluoride concentration. The prevalence of dental fluorosis was evaluated by a single trained examiner with excellent intraexaminer agreement (kappa = 0.95). Intraexaminer reproducibilities were calculated at tooth level. Sensitivity, specificity, positive and negative predictive values of the simplified TF compared to gold standard were 90.6 (95%CI: 86.6 to 93.6), 100 (95%CI: 95.3 to 100), 100 (95%CI: 98.3 to 100) and 77.5 (95%CI: 69.8 to 83.5), respectively. The ROC value was 0.953 (95%CI: 0.933 to 0.973). The simplified TF index proved suitable for determining the prevalence of dental fluorosis in regions with endemic fluorosis caused by the ingestion of water with high concentrations of fluoride
Competitividade entre cultivares de cevada e biótipo de azevém. I. Utilização de variáveis relativas.
O USO DO ALUMINOSSILICATO (SILVET®) COMO ADJUVANTE NA MELHORA DO ASPECTO DAS FEZES E DESEMPENHO DAS AVES
O controle da umidade da cama na criação comercial de aves é essencial, especialmente
no verão, quando há maior ingestão de água pelas aves e as fezes ficam muito liqüefeitas. Uma
solução é incorporar substâncias adsorventes de água na dieta, como aluminossilicato, que reduz a
água livre e proporciona menor umidade na cama. Este estudo teve por objetivo avaliar se o
aluminossilicato pode melhorar o aspecto das fezes ao ser adicionado na ração de frangos. Foi realizado
numa granja comercial em São José dos Pinhais-PR, utilizando-se dois tratamentos e quatro repetições
com 25 aves cada. No primeiro tratamento adicionou-se 1% de aluminossilicato (SilvetÒ) à dieta, no
segundo, o produto estava ausente. Dos 3 aos 40 dias de vida as aves receberam ração e água ad
libitum, sendo pesadas aos 22 e 40 dias e avaliadas quanto consumo de ração, ganho de peso e
conversão alimentar. Realizou-se também necropsia de 4 aves por tratamento, para observação de
possíveis lesões macroscópicas e colheita dos conteúdos intestinais que foram enviados para análise
de umidade total e cinzas. Os resultados foram submetidos a ANOVA, não havendo diferenças
significativas quanto ao desempenho das aves entre os tratamentos, entretanto, em ambas as idades
as porcentagens de cinzas e umidade total foram maiores nas aves que receberam aluminossilicato. A
inclusão do aluminossilicato na dieta não influencia no desempenho das aves, porém melhora o aspecto
fecal, aumentando a quantidade de matéria seca e reduzindo a umidade livre nas fezes excretadas.
The use of aluminossilicate (silvet®) as an adjuvant in broiler feces aspect and
performance improvement
Abstract
The control of bed humidity in the creations of r commercial broiler chicken is essential,
especially in the summer, when there is a larger ingestion of water the feces becoming more liquefied.
The incorporation of water adsorptive substances to the diet, such as the aluminossilicate, reduces the
free water and provides lower humidity in the bed. This study was carried out to evaluate the use of
aluminossilicate on feces aspect. Two treatments and four repetitions with 25 chicks each were performed
in a commercial farm in São José dos Pinhais-PR. At the first treatment 1% of aluminossilicate was
added (SilvetÒ) to the diet, while the product was absent in the other. From 3 to 40 days of life the chicks
received ration and water ad libitum and were weighted at days 22 and 40 and evaluated over ration
consumption, bodyweight gain and alimentary conversion. Necropsy of 4 chicks per treatment was
carried out in order to detect possible macroscopic lesions, collect intestinal contents and analyze total
humidity and ashes content in the feces. The results submitted to the statistical method ANOVA, did not
show expressive differences between the treatments for animal performance. However, in both ages
the total humidity and ash percentage were higher on broiler that received aluminossilicate. Aluminossilicate
inclusion on diet did not influence in the broiler performance, although it improved the feces aspect by
increasing the drought matter quantity and reducing the feces free humidity
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