991 resultados para 378.014
Resumo:
Background: Bronchiolitis caused by the respiratory syncytial virus (RSV) and its related complications are common in infants born prematurely, with severe congenital heart disease, or bronchopulmonary dysplasia, as well as in immunosuppressed infants. There is a rich literature on the different aspects of RSV infection with a focus, for the most part, on specific risk populations. However, there is a need for a systematic global analysis of the impact of RSV infection in terms of use of resources and health impact on both children and adults. With this aim, we performed a systematic search of scientific evidence on the social, economic, and health impact of RSV infection. Methods: A systematic search of the following databases was performed: MEDLINE, EMBASE, Spanish Medical Index, MEDES-MEDicina in Spanish, Cochrane Plus Library, and Google without time limits. We selected 421 abstracts based on the 6,598 articles identified. From these abstracts, 4 RSV experts selected the most relevant articles. They selected 65 articles. After reading the full articles, 23 of their references were also selected. Finally, one more article found through a literature information alert system was included. Results: The information collected was summarized and organized into the following topics: 1. Impact on health (infections and respiratory complications, mid-to long-term lung function decline, recurrent wheezing, asthma, other complications such as otitis and rhino-conjunctivitis, and mortality; 2. Impact on resources (visits to primary care and specialists offices, emergency room visits, hospital admissions, ICU admissions, diagnostic tests, and treatments); 3. Impact on costs (direct and indirect costs); 4. Impact on quality of life; and 5. Strategies to reduce the impact (interventions on social and hygienic factors and prophylactic treatments). Conclusions: We concluded that 1. The health impact of RSV infection is relevant and goes beyond the acute episode phase; 2. The health impact of RSV infection on children is much better documented than the impact on adults; 3. Further research is needed on mid-and long-term impact of RSV infection on the adult population, especially those at high-risk; 4. There is a need for interventions aimed at reducing the impact of RSV infection by targeting health education, information, and prophylaxis in high-risk populations.
Resumo:
Several alpine vertebrates share a distribution pattern that extends across the South-western Palearctic but is limited to the main mountain massifs. Although they are usually regarded as cold-adapted species, the range of many alpine vertebrates also includes relatively warm areas, suggesting that factors beyond climatic conditions may be driving their distribution. In this work we first recognize the species belonging to the mentioned biogeographic group and, based on the environmental niche analysis of Plecotus macrobullaris, we identify and characterize the environmental factors constraining their ranges. Distribution overlap analysis of 504 European vertebrates was done using the Sorensen Similarity Index, and we identified four birds and one mammal that share the distribution with P. macrobullaris. We generated 135 environmental niche models including different variable combinations and regularization values for P. macrobullaris at two different scales and resolutions. After selecting the best models, we observed that topographic variables outperformed climatic predictors, and the abruptness of the landscape showed better predictive ability than elevation. The best explanatory climatic variable was mean summer temperature, which showed that P. macrobullaris is able to cope with mean temperature ranges spanning up to 16 degrees C. The models showed that the distribution of P. macrobullaris is mainly shaped by topographic factors that provide rock-abundant and open-space habitats rather than climatic determinants, and that the species is not a cold-adapted, but rather a cold-tolerant eurithermic organism. P. macrobullaris shares its distribution pattern as well as several ecological features with five other alpine vertebrates, suggesting that the conclusions obtained from this study might be extensible to them. We concluded that rock-dwelling and open-space foraging vertebrates with broad temperature tolerance are the best candidates to show wide alpine distribution in the Western Palearctic.
Resumo:
Feature-based vocoders, e.g., STRAIGHT, offer a way to manipulate the perceived characteristics of the speech signal in speech transformation and synthesis. For the harmonic model, which provide excellent perceived quality, features for the amplitude parameters already exist (e.g., Line Spectral Frequencies (LSF), Mel-Frequency Cepstral Coefficients (MFCC)). However, because of the wrapping of the phase parameters, phase features are more difficult to design. To randomize the phase of the harmonic model during synthesis, a voicing feature is commonly used, which distinguishes voiced and unvoiced segments. However, voice production allows smooth transitions between voiced/unvoiced states which makes voicing segmentation sometimes tricky to estimate. In this article, two-phase features are suggested to represent the phase of the harmonic model in a uniform way, without voicing decision. The synthesis quality of the resulting vocoder has been evaluated, using subjective listening tests, in the context of resynthesis, pitch scaling, and Hidden Markov Model (HMM)-based synthesis. The experiments show that the suggested signal model is comparable to STRAIGHT or even better in some scenarios. They also reveal some limitations of the harmonic framework itself in the case of high fundamental frequencies.
Resumo:
Background: Health expectancy is a useful tool to monitor health inequalities. The evidence about the recent changes in social inequalities in healthy expectancy is relatively scarce and inconclusive, and most studies have focused on Anglo-Saxon and central or northern European countries. The objective of this study was to analyse the changes in socioeconomic inequalities in disability-free life expectancy in a Southern European population, the Basque Country, during the first decade of the 21st century. Methods: This was an ecological cross-sectional study of temporal trends on the Basque population in 1999-2003 and 2004-2008. All-cause mortality rate, life expectancy, prevalence of disability and disability free-life expectancy were calculated for each period according to the deprivation level of the area of residence. The slope index of inequality and the relative index of inequality were calculated to summarize and compare the inequalities in the two periods. Results: Disability free-life expectancy decreased as area deprivation increased both in men and in women. The difference between the most extreme groups in 2004-2008 was 6.7 years in men and 3.7 in women. Between 1999-2003 and 2004-2008, socioeconomic inequalities in life expectancy decreased, and inequalities in disability-free expectancy increased in men and decreased in women. Conclusions: This study found important socioeconomic inequalities in health expectancy in the Basque Country. These inequalities increased in men and decreased in women in the first decade of the 21st century, during which the Basque Country saw considerable economic growth.
Resumo:
Background: Non-alcoholic fatty liver disease (NAFLD) is caused by abnormal accumulation of lipids within liver cells. Its prevalence is increasing in developed countries in association with obesity, and it represents a risk factor for non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. Since NAFLD is usually asymptomatic at diagnosis, new non-invasive approaches are needed to determine the hepatic lipid content in terms of diagnosis, treatment and control of disease progression. Here, we investigated the potential of magnetic resonance imaging (MRI) to quantitate and monitor the hepatic triglyceride concentration in humans. Methods: A prospective study of diagnostic accuracy was conducted among 129 consecutive adult patients (97 obesity and 32 non-obese) to compare multi-echo MRI fat fraction, grade of steatosis estimated by histopathology, and biochemical measurement of hepatic triglyceride concentration (that is, Folch value). Results: MRI fat fraction positively correlates with the grade of steatosis estimated on a 0 to 3 scale by histopathology. However, this correlation value was stronger when MRI fat fraction was linked to the Folch value, resulting in a novel equation to predict the hepatic triglyceride concentration (mg of triglycerides/g of liver tissue = 5.082 + (432.104 * multi-echo MRI fat fraction)). Validation of this formula in 31 additional patients (24 obese and 7 controls) resulted in robust correlation between the measured and estimated Folch values. Multivariate analysis showed that none of the variables investigated improves the Folch prediction capacity of the equation. Obese patients show increased steatosis compared to controls using MRI fat fraction and Folch value. Bariatric surgery improved MRI fat fraction values and the Folch value estimated in obese patients one year after surgery. Conclusions: Multi-echo MRI is an accurate approach to determine the hepatic lipid concentration by using our novel equation, representing an economic non-invasive method to diagnose and monitor steatosis in humans.
Resumo:
This article analyzes changes in the occupational employment share in Spain for the period 1997-2012 and the way particular sociodemographic groups adapt to those changes. There seems to be clear evidence of employment polarization between 1997 and 2012 that accelerates over the recession. Changes in the composition of the labour supply cannot explain the increase in the share of occupations at the low end of the wage distribution. Sector reallocation may have partially contributed to explain the polarization process in Spain during the years of expansion (1997-2007) but it is a minor factor during the recession. The polarization of occupations within sectors observed, especially during the recession, appears to be related to a decline in routine tasks which is compensated by an increase in occupations with non-routine service contents, which are found both in the low and high end of the wage distribution. Instead, jobs with a higher degree of abstract contents do not appear to increase their share in total employment during these 15 years. The paper finds that this process has affected males more strongly than females because of their higher concentration in occupations more focused on routine tasks. Among males, for workers under 30 years old, we find a decrease in the share of occupations with more routine tasks which turns into increases in those with more abstract content and particularly with more non-routine service content. Instead, male workers over 30 years old seem to remain in declining occupations to a greater extent. Females of different ages are not affected by the abovementioned changes.
Resumo:
An interesting fluorescence intensity reverse photonic phenomenon between red and green fluorescence is investigated. The dynamic range. of intensity reverse between red and green fluorescence of Er( 0.5) Yb( 3): FOV oxyfluoride nanophase vitroceramics, when excited by 378.5nm and 522.5nm light respectively, is about 4.32 x 10(2). It is calculated that the phonon- assistant energy transfer rate of the electric multi- dipole interaction of {(4)G(11/2)( Er3+) -> F-4(9/2)( Er3+), F-2(7/2)( Yb3+). F-2(5/2)( Yb3+)} energy transfer of Er( 0.5) Yb( 3): FOV is around 1.380 x 10(8) s(-1), which is much larger than the relative multiphonon nonradiative relaxation rates 3.20 x 10(5) s(-1). That energy transfer rate for general material with same rare earth ion's concentration is about 1.194 x 10(5) s(-1). These are the reason to emerge the unusual intensity reverse phenomenon in Er( 0.5) Yb( 3): FOV. (C) 2007 Optical Society of America.
Resumo:
Effect of the substitutions of chloride for fluoride on the chemical and physical properties and the crystallization behavior in heavy metal fluoride glasses has been investigated. The characteristic temperature of the glass does not changed obviously when the fluoride was taken place by chloride. Compared with samples of being free of ErF3, the doping samples are more inclined to be surface crystallization. Optical basicity in the glass system increases with increasing the negative charge provided by the chloride atoms and the absorption peak red shifted is observed in absorption spectra. XRD measurements show that not a single crystalline phase appears in the heated glass samples, which indicate the substitutions of chloride for fluoride with a variety of crystalline precipitation trends. (c) 2007 Elsevier B.V All rights reserved.
Resumo:
通过优化熔融条件和玻璃组份,成功开发出一种新的Er^3+/Yb^3+共掺磷酸盐玻璃,其在沸水和熔盐中均表现出很好的化学稳定性。通过分析室温下Er^3+/Yb^3+共掺磷酸盐玻璃的吸收光谱,计算得到了Er^3+离子在波长1533nm处的峰值发射截面和杜得-奥菲而特强度参数;其中Er^3+离子在波长1533nm处的峰值发射截面为0.72×10^20cm^2,大于Schott的IOG1玻璃中Er^3+离子的峰值发射截面0.67×10^-20cm^2。通过改变离子交换的条件,获得了1.55μm单模光波导的制作条件
Resumo:
A new calibration method for a photoelastic modulator is proposed. The calibration includes a coarse calibration and a fine calibration. In the coarse calibration, the peak retardation of the photoelastic modulator is set near 1.841 rad. In the fine calibration, the value of the zeroth Bessel function is obtained. The zeroth Bessel function is approximated as a linear equation to directly calculate the peak retardation. In experiments, the usefulness of the calibration method is verified and the calibration error is less than 0.014 rad. The calibration is immune to the intensity fluctuation of the light source and independent of the circuit parameters. The method specially suits the calibration of a photoelastic modulator with a peak retardation of less than a half-wavelength. (c) 2007 Optical Society of America.
Resumo:
A lesão medular está associada a uma série de alterações bioquímicas e decomposição corporal. O aumento da gordura corporal e seu acúmulo na regiãoabdominal aliados a processos infecciosos decorrentes da lesão medular podemacarretar o incremento da concentração plasmática da proteína c-reativa (PCR).Tanto a gordura corporal quanto a elevada concentração da PCR estimulam aprodução de espécies reativas de oxigênio, favorecendo o desequilíbrio oxidativo e odesencadeamento de doenças. É possível que a prática de atividade física regularpossa atuar de modo benéfico através da melhor distribuição da gordura corporal eadaptação dos sistemas antioxidantes nesses indivíduos. Considerando aimportância deste tema e a escassos estudos sobre o assunto, o objetivo desteestudo foi comparar, em indivíduos com lesão medular cervical a composiçãocorporal e indicadores bioquímicos de estado antioxidante em indivíduos fisicamenteativos e não ativos. Participaram do estudo 24 tetraplégicos do gênero masculino(3210 anos de idade e 108 anos de tempo de lesão), divididos em dois grupos,fisicamente ativos (n=15, com pratica de atividade física há pelo menos 3 meses, 3vezes/semana ou mais, totalizando tempo mínimo de 150 minutos/semana) e nãoativos (n=9). A composição corporal foi determinada por absorciometria de duplaemissão de raio-X. Amostras de sangue foram coletadas após jejum de 12 horaspara determinação dos indicadores bioquímicos: de capacidade antioxidante, ácidoúrico, bilirrubina, albumina, alfa-tocoferol, malondialdeído e PCR no plasma eatividade da superóxido dismutase em eritrócitos. O grupo não ativo apresentoumaior IMC (=0,003), gordura total (%) e de tronco (%) (=<0,001) do que o grupoppfisicamente ativo. Foi encontrada relação entre a PCR e a porcentagem de gorduratotal (r=0,72, p=<0,001), de tronco (r=0,70, p=<0,001), massa gorda total (r=0,73,p=<0,001) e de tronco (r=0,67, p=0,001). Não houve diferença significativa entre osindicadores bioquímicos de estado antioxidante, exceto a concentração da PCR quefoi maior no grupo não ativo (p=0,034). Considerando todos indivíduos, 50% apresentavam deficiência de alfa-tocoferol (concentração plasmática <11,6 mol/L).Foi observada relação negativa entre a concentração plasmática de alfa-tocoferol e aPCR (r=-0,18, =0,038).No grupo ativo houve correlação positiva entre a razãoptempo de atividade física:tempo de lesão e concentração plasmática demalondialdeido (r=0,38, =0,014). Nossos resultados, analisados em conjunto,psugerem que prática contínua de atividade física após a lesão atua auxiliando a umamelhor composição corporal e, possivelmente, a uma menor concentraçãoplasmática de PCR. O estado nutricional inadequado em alfa-tocoferol podecomprometer capacidade antioxidante, sendo necessárias medidas de apoionutricional para adequar a ingestão de alfa-tocoferol para este grupo.
Resumo:
ZnO thin films were grown on (0001)LiNbO3 substrates by the MOCVD technique. The substrate temperatures during growth were changed from 400 to 600 degrees C. The X-ray diffraction (XRD) pattern of the ZnO film showed a strong [002] reflection peak, and the peak intensity was dependent on substrate temperature. The ZnO columnar grains were highly oriented along the (002) direction when the film processing temperature was 600 degrees C. The optical transmission and PL results also indicated that highest crystalline quality of the ZnO films could be obtained at elevated temperatures. (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
A obesidade é uma doença crônica não transmissível, caracterizada pelo excesso de gordura corporal. Então, a gordura acumulada na região abdominal promove resistência à insulina e conseqüentemente alterações metabólicas as quais em conjunto configuram o quadro de síndrome metabólica (SM). O genótipo Pro12Pro parece estar relacionado à menor sensibilidade à insulina, desencadeando o processo fisiopatológico da SM. Então, o objetivo deste trabalho foi avaliar o efeito de uma dieta hipocalórica sobre o perfil metabólico e composição corporal de mulheres com e sem SM com genótipo Pro12Pro no gene PPARγ2. O presente estudo trata-se de um ensaio clínico, onde mulheres entre 30 e 45 anos, obesas grau I, sem SM (n=23) e com SM (n=7) foram submetidas à dieta hipocalórica por 90 dias. A identificação do genótipo foi realizada por reação em cadeia da polimerase (PCR). No início e nos dias 30, 60 e 90 foram avaliados peso corporal, massa magra (MM), massa gorda (MG), componentes da SM, uricemia, insulinemia, leptinemia, adiponectinemia, os índices HOMA-IR e QUICKI. O consumo energético foi avaliado nas 12 semanas de tratamento. Foi utilizado o teste t de Student para amostras independentes foi utilizado para comparar os grupos entre si, e o modelo pareado para comparar a evolução dentro de cada grupo em relação ao início do estudo. Todas as mulheres apresentaram genótipo Pro12Pro. O grupo com SM apresentou menor HDL-c (44,43,2 vs. 56,82,4 mg/dL, p=0,013), e maior triglicerídeo (180,926,7 vs. 89,76,6mg/dL, p=0,014) e VLDL-c (36,25,3 vs. 17,91,3mg/dL, p=0,014) no início do estudo. Ambos os grupos apresentaram redução ponderal (-3,30,7% grupo sem SM e - 4,20,9% grupo com SM) e da circunferência da cintura (-2,40,5% grupo sem SM e - 5,91,4% grupo com SM) significativas. O grupo sem SM reduziu da MG progressivamente até os 90 dias (37,00,8 para 36,60,5%, p=0,02), e com isso aumentou MM (62,00,5 para 63,40,5%, p=0,01), o grupo com SM também reduziu MG ao longo do estudo (32,62,3 para 29,62,4%, p<0,01) e aumentou MM significativamente (62,21,0 para 64,31,3%). A pressão arterial sistólica reduziu no primeiro mês de tratamento no grupo sem SM (de 120,41,8 para 112,32,1 mmHg, p<0,01). No que diz respeito aos parâmetros metabólicos, o grupo sem SM mostrou redução da insulinemia (32,54,2 para 25,92,4U/mL, p=0,05) e aumento da adiponectinemia (4,70,6 para 5,10,8 ng/mL, p=0,02) aos 30 dias, do colesterol total (180,25,8 para 173,85,4 mg/dL, p=0,04), e da leptina (27,01,9 para 18,21,4 ng/mL, p<0,01) aos 60 dias, porém, houve redução do QUICKI aos 90 dias (0,390,03 para 0,350,01, p=0,01). No grupo com SM, a leptinemia reduziu aos 60 dias (20,31,9 para 14,71,1 ng/mL, p=0,01) e a adiponectinemia aos 90 dias (5,71,2 para 7,11,4 ng/mL, p<0,01), também houve remissão de 57,1% dos casos de SM. Sugerimos que, a dieta hipocalórica foi eficaz na redução do peso corporal e da MG, principalmente a localizada na região abdominal. Conseqüentemente, houve melhora considerável do perfil metabólico relacionado à obesidade no grupo sem SM, e também dos marcadores de sensibilidade à insulina e cardioprotetores relacionados à SM, além da remissão dos casos de SM.