823 resultados para 985
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In a recent paper, Robert Putnam (2007) challenges the contact hypothesis by arguing that ethnic diversity causes people to ‘hunker down’ and essentially withdraw themselves from society. Drawing on
qualitative data collected from three mixed communities in Northern Ireland, this paper explores the extent and quality of contact experienced by Protestants and Catholics in their everyday lives. Themes emerging from our data are generally consistent with the contact hypothesis. There is also some support for Putnam’s theory that mixed environments can induce ‘hunkering down’ and that inter-group trust may be compromised. However, our data challenge Putnam’s argument that these responses are a consequence of ‘anomie’ or ‘social malaise’. Rather, we find that withdrawal from social activity in the neighbourhoods we observed was a calculated response at times of threat, often aimed at protecting existent positive inter-ethnic relations.
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Purpose: To determine the yields of cell lethality and micronucleus formation measured immediately after irradiation or at delayed times in primary human fibroblasts exposed to X-rays or alpha-particles.
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This paper presents a new technique for the detectionof islanding conditions in electrical power systems. This problem isespecially prevalent in systems with significant penetrations of distributedrenewable generation. The proposed technique is based onthe application of principal component analysis (PCA) to data setsof wide-area frequency measurements, recorded by phasor measurementunits. The PCA approach was able to detect islandingaccurately and quickly when compared with conventional RoCoFtechniques, as well as with the frequency difference and change-ofangledifference methods recently proposed in the literature. Thereliability and accuracy of the proposed PCA approach is demonstratedby using a number of test cases, which consider islandingand nonislanding events. The test cases are based on real data,recorded from several phasor measurement units located in theU.K. power system.
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The histamine H4 receptor regulates the inflammatory response. However, it is not known whether this receptor has a functional role in human neutrophils. We found that fMLP (1 μM), but not histamine (0.1-1 μM), induced Mac-1-dependent adhesion, polarization, and degranulation (release of lactoferrin). A pretreatment of neutrophils with histamine (0.001-1 μM) or JNJ 28610244 (0.1-10 μM), a specific H4 receptor agonist, led to inhibition of degranulation. Total inhibition of degranulation was obtained with 0.1 μM histamine and 10 μM JNJ 28610244. Furthermore, such inhibition by histamine of degranulation was reversed by JNJ 7777120 and JNJ 28307474, two selective H4 receptor antagonists. However, neither histamine nor the H4 receptor agonist JNJ 28610244 prevented fMLP-induced, Mac-1-dependent adhesion, indicating that the H4 receptor may block signals emanating from Mac-1-controlling degranulation. Likewise, engagement of the H4 receptor by the selective agonist JNJ 28610244 blocked Mac-1-dependent activation of p38 MAPK, the kinase that controls neutrophil degranulation. We also show expression of the H4 receptor at the mRNA level in ultrapure human neutrophils and myeloid leukemia PLB-985 cells. We concluded that engagement of this receptor by selective H4 receptor agonists may represent a good, therapeutic approach to accelerate resolution of inflammation.
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Two hundred seven vitamin A-deficient southern Indian children aged 1-7 y (mean age: 56.9 mo) underwent testing of dark-adapted visual and pupillary thresholds in their village setting according to a previously reported protocol. One hundred thirty (62.8%) of the children also underwent serum retinol testing, and 178 (86.0%) participated in a randomized, placebo-controlled vitamin A dosing trial with pre- and postdose testing of dark-adaptation threshold. Most subjects (184 of 207, 88.9%) were able to complete pupillary testing, an objective sign requiring minimal cooperation, including a high proportion of the youngest children (72.2% of subjects aged 2 y). The proportion of children completing visual threshold testing, which requires greater understanding and cooperation, was significantly smaller than that able to complete pupillary testing (131 of 207, 63.3%; P < 0.0001, chi square). At baseline (predosing), the mean serum retinol concentration declined in linear fashion with a higher pupillary threshold (0.73 mumol/L with a score < or = 4; 0.47 mumol/L with a score > or = 8; P < 0.01). The mean pupillary threshold for these highly vitamin A-deficient Indian children (-0.622 log cd/m2) was significantly higher than that for 136 more moderately deficient Indonesian children (-0.985 log cd/m2; P < 0.001, two-sample t test) and 56 normal American children (-1.335 log cd/m2; P < 0.0001, two-sample t test). The improvement in pupillary dark-adaptation testing was not significant for children receiving vitamin A or placebo, though there was a nonsignificant trend toward greater improvement in children receiving vitamin A (P = 0.2, two-sample t test). Pupillary threshold testing represents a new, noninvasive, practical, and seemingly valid approach to assessing the vitamin A status of a moderately to severely deficient preschool population.
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Indústrias metalúrgicas de produção de ligas metálicas podem por em risco toda a área envolvente, nomeadamente a qualidade das águas (superficiais e subterrâneas), dos solos e do ar, sempre que não existam infraestruturas e planos adequados de gestão destes resíduos. No caso em estudo, a unidade industrial situa-se na bacia do rio São Francisco, no estado brasileiro de Minas Gerais, e nos mais de quarenta anos de funcionamento tem produzido inúmeros problemas ambientais. Este estudo baseia-se nos primeiros resultados referentes aos solos da envolvente, tendo como objetivos a identificação dos principais contaminantes e a definição da área contaminada, de forma a avaliar a eficácia de projetos futuros de recuperação.
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One of the predictions of the ‘challenge hypothesis’ (Wingfield et al., 1990) is that androgen patterns during the breeding season should vary among species according to the parenting and mating system. Here we assess this prediction of the challenge hypothesis both at the intra- and at the inter-specific level. To test the hypothesis at the inter-specific level, a literature survey on published androgen pat- terns from teleost fish with different mating systems was carried out. The results confirm the predicted effect of mating system on andro- gen levels. To test the hypothesis at an intra-specific level, a species with flexible reproductive strategies (i.e. monogamy vs. polygyny), the Saint Peter’s fish was studied. Polygynous males had higher 11- ketotestosterone levels. However, males implanted with methyl-tes- tosterone did not became polygynous and the variation of the ten- dency to desert their pair mates was better explained by the repro- ductive state of the female partner. This result stresses the point that the effects of behaviour on hormones cannot be considered without respect to the social context.
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The objectives of this paper are to ascertain the main factors involved in the phenological mechanism of alder flowering in Central Europe by understanding the in - fluence of the main meteorological parameters, the North Atlantic Oscillation (NAO) effect and the study of the Chill and Heat requirements to overcome dormancy. Airborne pollen (1995–2007) was collected in Poznań (Poland) by means a volumetric spore trap. Temperatures for February, and January and February averages of the NAO are generally key factors affecting the timing of the alder pollen seasons. Chilling accumulation (which started in Poznań at the beginning of November, while the end took place during the month of January) of 985 CH with a threshold temperature of -0.25ºC, followed by 118 GDDºC with a threshold temperature of 0.5ºC, were necessary to overcome dormancy and produce the onset of flowering. The calculated dormancy requirements, mean tem - peratures of the four decades of the year, and January and February average NAO index recorded during the period before flowering, were used to construct linear and multiple regression models in order to forecast the start date of the alder pollen seasons Its ac - curacy was tested using data from 2007, and the difference between the predicted and observed dates ranged from 3–7 days
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Magnetic resonance imaging is a diagnostic tool used for detecting abnormal organs and tissues, often using Gd(III) complexes as contrast-enhancing agents. In this work, core–shell polymer fibers have been prepared using coaxial electrospinning, with the intent of delivering gadolinium (III) diethylenetriaminepentaacetate hydrate (Gd(DTPA)) selectively to the colon. The fibers comprise a poly(ethylene oxide) (PEO) core loaded with Gd(DTPA), and a Eudragit S100 shell. They are homogeneous, with distinct core–shell phases. The components in the fibers are dispersed in an amorphous fashion. The proton relaxivities of Gd(DTPA) are preserved after electrospinning. To permit easy visualization of the release of the active ingredient from the fibers, analogous materials are prepared loaded with the dye rhodamine B. Very little release is seen in a pH 1.0 buffer, while sustained release is seen at pH 7.4. The fibers thus have the potential to selectively deliver Gd(DTPA) to the colon. Mucoadhesion studies reveal there are strong adhesive forces between porcine colon mucosa and PEO from the core, and the dye-loaded fibers can be successfully used to image the porcine colon wall. The electrospun core–shell fibers prepared in this work can thus be developed as advanced functional materials for effective imaging of colonic abnormalities.
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Solubilities of red 153, (3-[[4-[[5,6(or 6,7)-dichloro-2-benzothiazolyl]azo]phenyl]ethylamino]propanenitrile), an azo compound, and disperse blue1 (1,4,5,8-tetraaminoantraquinone) in supercritical carbon dioxide (SC CO(2)) were measured at T = (333.2 to 393.2) K over the pressure range (12.0 to 40.0) MPa by a flow type apparatus. The solubility of red 153 (0.985. 10(-6) to 37.2. 10(-6)) in the overall region of measurements is found to be significantly higher than that of disperse blue 1 (1.12.10(-7) to 4.89.10(-7)). The solubility behavior of disperse red 153 follows the general solubility trend displayed by disperse dyes with a crossover pressure at about 20 MPa. On the other hand, blue 1, which is a disperse anthraquinone dye, exhibits unexpected behavior not recorded previously there is no crossover pressure at the temperature and pressure ranges studied, and the dye's solubility at T = 333.2 K practically does not increase with pressure. To the best of our knowledge, there are no previous measurements of blue 1 solubility in SC CO(2) reported in the literature. The experimental data were correlated by using the Soave Redlich Kwong equation of state (EoS) with the one-fluid van der Waals mixing rule, and an acceptable correlation of the solubility data for both dyes was obtained.
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RESUMO - Introdução: Actualmente 11,3 milhões de indivíduos estão co-infectados pela Tuberculose/Vírus Imunodeficiência Humana (TB/VIH), uma das principais causas de incapacidade e morte no mundo. É determinada pela exposição dos indivíduos aos factores de risco e condições/determinantes sociais de saúde. Várias são as medidas criadas a nível nacional e internacional na luta contra TB e a infecção VIH. Objectivo: Caracterizar e comparar os casos de TB entre os indivíduos não infectados com VIH e os infectados com VIH, considerando as características sócio-demográficas, o tratamento, patologias associadas e factores de risco. Método: Estudo descritivo, quantitativo e observacional. A informação foi obtida a partir da base de dados do Sistema Nacional de Vigilância Epidemiológica da Tuberculose dos casos de TB notificados entre 1 de Janeiro de 2008 a 31 de Dezembro de 2009. Para tratamento e análise estatística (descritiva e inferencial) o programa usado foi o SPSS versão 18,0. Resultados: 12,8% dos indivíduos estavam co-infectados com TB/VIH e 87,2% não estavam co-infectados. A presença de VIH nos casos de tuberculose apresenta evidência de relação com quase todas variáveis em estudo (p<0,00) excepto a presença de insuficiência renal (p<0,307). Apresentam maior probalidade de risco da co-infecção TB/VIH os homens, a faixa etária [35;44[, os estrangeiros, os desempregados, estar em retratamento e fumar. Os indivíduos com Doença Hepática (OR= 5,238; IC95%: 3,706;7,403; ORA = 3,104; IC95%: 2,164;4,454), patologias associadas (OR=13,199; IC95%: 11,246; 15,491; ORA=21,348; IC95%:17,569; 25,940) e factores de risco (OR=3,237; IC95%: 2,968; 3,531; ORA=2,644; IC95%: 2,414; 2,985) tem maior probalidade da co-infecção TB/VIH. O ajustamento para o sexo e a idade interferiu em todas variáveis em estudo. Conclusão: Os homens, da faixa etária [35;44 [, desempregados, estrangeiros, em retratamento, fumadores apresentam maior probalidade de risco de estar co-infectado com TB/VIH.
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An assessment of sewage workers' exposure to airborne cultivable bacteria, fungi and inhaled endotoxins was performed at 11 sewage treatment plants. We sampled the enclosed and unenclosed treatment areas in each plant and evaluated the influence of seasons (summer and winter) on bioaerosol levels. We also measured personal exposure to endotoxins of workers during special operation where a higher risk of bioaerosol inhalation was assumed. Results show that only fungi are present in significantly higher concentrations in summer than in winter (2331 +/- 858 versus 329 +/- 95 CFU m(-3)). We also found that there are significantly more bacteria in the enclosed area, near the particle grids for incoming water, than in the unenclosed area near the aeration basins (9455 +/- 2661 versus 2435 +/- 985 CFU m(-3) in summer and 11 081 +/- 2299 versus 2002 +/- 839 CFU m(-3) in winter). All bioaerosols were frequently above the recommended values of occupational exposure. Workers carrying out special tasks such as cleaning tanks were exposed to very high levels of endotoxins (up to 500 EU m(-3)) compared to routine work. The species composition and concentration of airborne Gram-negative bacteria were also studied. A broad spectrum of different species within the Pseudomonadaceae and the Enterobacteriaceae families were predominant in nearly all plants investigated. [Authors]
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En el Laboratorio de Huachipa del Instituto del Mar del Perú, en el período comprendido entre octubre de 1980 y agosto de 1982, se realizaron varios experimentos a fin de determinar el efecto del tipo de estanque, densidad de carga y calidad y cantidad de fertilizante en el crecimiento y la producción de Tilapia nilotica. Estos experimentos arrojaron una diferencia no significativa entre los tratamientos, por lo cual se halló una cifra general promedio de crecimiento y producción que permitió su comparación con las cifras de producción obtenidas en otras áreas del mundo, un peso individual promedio de 203.4 g, una producción total de 2,038 Kg/ha/272 días, y una producción neta de 5.6 Kg/ha/día. Cifras que quedan dentro del rango reportado por el ICA (International Center for Aquaculture) para clima templado; similares a las obtenidas en países de Europa Central y la China, y notablemente bajas comparadas con los 20 Kg/ha/día producidos en Israel. Se identifican la mala condición de los estanques utilizados, la baja densidad de carga aplicada, la baja calidad del fertilizante y el clima de la zona, específicamente la presencia de nubosidad, como los factores de mayor incidencia en los resultados poco satisfactorios.
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Las especies de peces pelágicos son las más abundantes del Pacífico Sudeste y sustentan una de las pesquerías más importantes del mundo, como la de anchoveta (Engraulis ringens). Durante los eventos El Niño ocurridos en las décadas recientes y catalogados como fuertes o muy fuertes, la abundancia de anchoveta decayó por varios factores; luego de cada evento de fuerte intensidad fue reemplazada en el ambiente por otros recursos. Durante la Niña la situación se invierte, siendo normalmente la anchoveta la especie predominante en abundancia debido a su rápido crecimiento y reproducción, y a la mayor disponibilidad de alimento de ese período. En general, la abundancia de anchoveta muestra una correlación negativa con la de otros recursos pelágicos, particularmente la sardina, aunque se carece de un modelo que establezca esta relación.
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Durante la primavera 2005, con la red Hensen (330 μm) se colectaron 104 muestras de zooplancton entre Paita y Cerro Azul hasta 50 m de profundidad. Se determinaron huevos y larvas pertenecientes a 20 familias, 22 géneros y 31 especies. Engraulis ringens fue más frecuente y abundante; se registraron huevos (64,1%) y larvas (70,9%), con abundancias que fluctuaron entre 3 y 23.184 huevos/m2 y entre 3 y 5.340 larvas/m2. La longitud total (LT) de las larvas fluctuó entre 2 y 20 mm, las más abundantes (91,6%) fueron larvas entre 2 y 4 mm LT. De Vinciguerria lucetia se registró huevos (35,6%) y larvas (28,8%) y de Diogenichthys laternatus larvas con 32,7%. El índice de diversidad (H), registró valores entre 0,001 y 1,54 bits/Ind., la equidad (J) varió entre 0,002 y 0,985 y la riqueza de especies (d) entre 0,099 y 1,430. Los volúmenes de zooplancton estuvieron comprendidos entre 0,4 y 55 mL/muestra, con un promedio +desviación estándar de 7,30 +8,10 mL/muestra.