658 resultados para 852


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Mineral dust has a large impact on regional and global climate, depending on its particle size. Especially in the Atlantic Ocean downwind of the Sahara, the largest dust source on earth, the effects can be substantial but are poorly understood. This study focuses on seasonal and spatial variations in particle size of Saharan dust deposition across the Atlantic Ocean, using an array of submarine sediment traps moored along a transect at 12° N. We show that the particle size decreases downwind with increased distance from the Saharan source, due to higher gravitational settling velocities of coarse particles in the atmosphere. Modal grain sizes vary between 4 and 33 µm throughout the different seasons and at five locations along the transect. This is much coarser than previously suggested and incorporated into climate models. In addition, seasonal changes are prominent, with coarser dust in summer, and finer dust in winter and spring. Such seasonal changes are caused by transport at higher altitudes and at greater wind velocities during summer than in winter. Also the latitudinal migration of the dust cloud, associated with the Intertropical Convergence Zone, causes seasonal differences in deposition as the summer dust cloud is located more to the north, and more directly above the sampled transect. Furthermore, increased precipitation and more frequent dust storms in summer coincide with coarser dust deposition. Our findings contribute to understanding Saharan dust transport and deposition relevant for the interpretation of sedimentary records for climate reconstructions, as well as for global and regional models for improved prediction of future climate.

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We examine alcohol use in conjunction with ecstasy use and risk-taking behaviors among regular ecstasy users in every capital city in Australia. Data on drug use and risks were collected in 2004 from a national sample of 852 regular ecstasy users (persons who had used ecstasy at least monthly in the preceding 6 months). Users were grouped according to their typical alcohol use when using ecstasy: no use, consumption of between one and five standard drinks, and consumption of more than five drinks (binge alcohol use). The sample was young, well educated, and mainly working or studying. Approximately two thirds (65%) of the regular ecstasy users reported drinking alcohol when taking ecstasy. Of these, 69% reported usually consuming more than five standard drinks. Those who did not drink alcohol were more disadvantaged, with greater levels of unemployment, less education, higher rates of drug user treatment, and prison history. They were also more likely than those who drank alcohol when using ecstasy to be drug injectors and to be hepatitis C positive. Excluding alcohol, drug use patterns were similar between groups, although the no alcohol group used cannabis and methamphetamine more frequently. Binge drinkers were more likely to report having had three or more sexual partners in the past 6 months and were less likely to report having safe sex with casual partners while under the influence of drugs. Despite some evidence that the no alcohol group were more entrenched drug users, those who typically drank alcohol when taking ecstasy were as likely to report risks and problems associated with their drug use. It appears that regular ecstasy users who binge drink are placing themselves at increased sexual risk when under the influence of drugs. Safe sex messages should address the sexual risk associated with substance use and should be tailored to reducing alcohol consumption, particularly targeting heavy alcohol users. The study's limitations are noted.

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Esta pesquisa tem o propósito de analisar o jornalismo de serviço em dois casos da mídia impressa brasileira: o jornal Folha de S. Paulo e a revista Veja, incluindo a revista Veja São Paulo. O que se buscou foi entender como o jornalismo de serviço, também denominado de gênero utilitário ou espécies utilitárias, está presente no jornalismo impresso atual. Em um primeiro momento realizou-se revisão bibliográfica sobre esta modalidade de produção jornalística. A seguir, fez-se uma pesquisa exploratória sobre o material de jornalismo de serviço publicado nos objetos estudados. Em terceiro momento, foi efetuada uma abordagem quantitativa dos formatos e tipos do gênero utilitário nesses veículos em questão, em edições selecionadas no ano de 2008. E, por último, através de entrevistas semi-abertas com editores da Veja e da Folha de S. Paulo, pretendeu-se entender os motivos que subsidiam as decisões editorais a respeito de tal modalidade jornalística. A análise revelou a presença deste gênero jornalístico desde o início da publicação desses veículos até os dias atuais. Contatou-se a existência de seis formatos, sendo quatro deles já identificados por Marques de Melo, e dois identificados nesta pesquisa, que foram considerados como tipos híbridos de gêneros.(AU)

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This study examines the cultural value orientations (VOs) of employees (managerial and non-managerial) working in three categories of organizations (professional, technical and local services) in India, Poland, Russia and the USA. The analysis is conducted at both the national and organizational levels. The paper hypothesizes cultural differences at the country level and cultural similarities among employees working for professional and technical oriented organizations and divergence in the VOs of employees working for local services organizations. It also hypothesizes differences in the VOs of managerial and non-managerial employees in the four countries. The investigation has been conducted with the help of a questionnaire survey of 1,852 respondents. The outcomes of the analysis show that there are both cross-country cultural differences and similarities among the VOs of employees of the four nations. Further, significant cultural convergence emerges in the VOs of employees working for both professional and technical organizations, however, no significant cultural similarities or differences are observed for employees of service-based organizations in the four countries. There are some similarities emerging between managerial employees in the research countries. The research contributes to the fields of cross-cultural management, international management and international human resource management.

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This research paper presents an examination of the journey to and from crime for autotheft offenders in the UK. For 852 offences, ‘wheel’ distances are calculated for triangles formed by offenders’ home location, theft location, and vehicle disposal location. The study demonstrates typical isosceles mobility triangles; distances travelled to and from home locations are roughly equal, whereas distances between theft and disposal points were shorter. Distances travelled by offenders under 17 years old and offences involving drug and drink were shown to be shorter than comparison groups. Prolifi c offenders tend to travel further, although there is signifi cant variation in this subgroup. Explanations and implications are discussed.

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We report on an optical bend sensor based on a Bragg grating inscribed in an eccentric core polymer optical fiber. The device exhibits the strong fiber orientation dependence, the wide bend curvature range of ± 22.7 m-1 and high bend sensitivity of 63 pm/m-1.

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Adjuvant arthritis (AA) is a condition that involves systemic oxidative stress. Unexpectedly, it was found that sarcoplasmic reticulum Ca2 +-ATPase (SERCA) activity was elevated in muscles of rats with AA compared to controls, suggesting possible conformational changes in the enzyme. There was no alteration in the nucleotide binding site but rather in the transmembrane domain according to the tryptophan polar/non-polar fluorescence ratio. Higher relative expression of SERCA, higher content of nitrotyrosine but no increase in phospholipid oxidation in AA SR was found. In vitro treatments of SR with HOCl showed that in AA animals SERCA activity was more susceptible to oxidative stress, but SR phospholipids were more resistant and SERCA could also be activated by phosphatidic acid. It was concluded that increased SERCA activity in AA was due to increased levels of SERCA protein and structural changes to the protein, probably induced by direct and specific oxidation involving reactive nitrogen species.

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This paper aims to reducing difference between sketches and photos by synthesizing sketches from photos, and vice versa, and then performing sketch-sketch/photo-photo recognition with subspace learning based methods. Pseudo-sketch/pseudo-photo patches are synthesized with embedded hidden Markov model. Because these patches are assembled by averaging their overlapping area in most of the local strategy based methods, which leads to blurring effect to the resulted pseudo-sketch/pseudo-photo, we integrate the patches with image quilting. Experiments are carried out to demonstrate that the proposed method is effective to produce pseudo-sketch/pseudo-photo with high quality and achieve promising recognition results. © 2009.

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Bulgarian and world computer science lost a prominent colleague: Dimitar Petrov Shishkov 22th January 1939, Varna – 8th March 2004, Sofia D. Shishkov graduated mathematics at Sofia University in 1962. In the last year of his studies he started a specialization as a programmer at the Joint Institute of Nuclear Research – Dubna which lasted three years. Then he worked at the Institute of Mathematics for two years. In 1966 D. Shishkov together with a group of experts transferred to the newly created Central Laboratory for Information Technologies. In 1976 he defended his PhD dissertation. He has been an associate professor in computer science at Sofia University since 1985 and a professor in computer science since 2000. His scientific interests and results were in the fields of computer architectures, computational linguistics, artificial intelligence, numerical methods, data structures, etc. He was remarkable with his teaching activities. D. Shishkov was the creator of high-quality software for the first Bulgarian electronic calculator “ELKA” – one of the first calculators in the world as well as for the series of next calculators and for specialized minicomputers. He was the initiator of the international project “Computerization of the natural languages”. He was a member of a range of international scientific organizations. Among his numerous activities was the organization of the I-st Programming competition in 1979. D. Shishkov was the initiator of sport dancing in Bulgaria (1967) and founder of the first sport-dancing high school education in the world. D. Shishkov was a highly accomplished person with a diversity of interests, with a developed social responsibility and accuracy in his work. In 1996 D. Shishkov was awarded with the International Prize ITHEA for outstanding achievements in the field of Information Theories and Applications. We are grateful to D. Shishkov for the chance to work together with him for establishment and development of IJ ITA.

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Developing novel heterojunction photocatalysts is a powerful strategy for improving the separation efficiency of photogenerated charge carriers, which is attracting the intense research interest in photocatalysis. Herein we report a highly efficient hetero/nanojunction consisting of Ag2CO3 nanoparticles grown on layered g-C3N4 nanosheets synthesized via a facile and template free in situ precipitation method. The UV–vis diffuse reflectance studies revealed that the synthesized Ag2CO3/g-C3N4 hetero/nanojunctions exhibit a broader and stronger light absorption in the visible light region, which is highly beneficial for absorbing the visible light in the solar spectrum. The optimum photocatalytic activity of Ag2CO3/g-C3N4 at a weight content of 10% Ag2CO3 for the degradation of Rhodamine B was almost 5.5 and 4 times as high as that of the pure Ag2CO3 and g-C3N4, respectively. The enhanced photocatalytic activity of the Ag2CO3/g-C3N4 hetero/nanojunctions is due to synergistic effects including the strong visible light absorption, large specific surface area, and high charge transfer and separation efficiency. More importantly, the high photostability and low use of the noble metal silver which reduces the cost of the material. Therefore, the synthesized Ag2CO3/g-C3N4 hetero/nanojunction photocatalyst is a promising candidate for energy storage and environment protection applications.

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Existing political theory, particularly which deals with justice and/or rights, has long assumed citizenship as a core concept. Noncitizenship, if it is considered at all, is generally defined merely as the negation or deprivation of citizenship. As such, it is difficult to examine successfully the status of noncitizens, obligations towards them, and the nature of their role in political systems. This article addresses this critical gap by defining the theoretical problem that noncitizenship presents and demonstrating why it is an urgent concern. It surveys the contributions to the special issue for which the article is an introduction, drawing on cross-cutting themes and debates to highlight the importance of theorising noncitizenship due to both the problematic gap that exists in the theoretical literature, and the real world problems created as a result of noncitizenship which are not currently successfully addressed. Finally, the article discusses key future directions for the theorisation of noncitizenship.

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Waste biomass is generated during the conservation management of semi-natural habitats, and represents an unused resource and potential bioenergy feedstock that does not compete with food production. Thermogravimetric analysis was used to characterise a representative range of biomass generated during conservation management in Wales. Of the biomass types assessed, those dominated by rush (Juncus effuses) and bracken (Pteridium aquilinum) exhibited the highest and lowest volatile compositions respectively and were selected for bench scale conversion via fast pyrolysis. Each biomass type was ensiled and a sub-sample of silage was washed and pressed. Demineralization of conservation biomass through washing and pressing was associated with higher oil yields following fast pyrolysis. The oil yields were within the published range established for the dedicated energy crops miscanthus and willow. In order to examine the potential a multiple output energy system was developed with gross power production estimates following valorisation of the press fluid, char and oil. If used in multi fuel industrial burners the char and oil alone would displace 3.9 × 105 tonnes per year of No. 2 light oil using Welsh biomass from conservation management. Bioenergy and product development using these feedstocks could simultaneously support biodiversity management and displace fossil fuels, thereby reducing GHG emissions. Gross power generation predictions show good potential.

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Tanulmányunkban a European Values Study adatai alapján megvizsgáljuk, miben tér el Európában a vállalkozók értékrendje más társadalmi csoportokétól, különös tekintettel az egyéni és a kormányzati felelősségvállalás megítélésére. Kísérletet teszünk a vállalkozói értékrend különböző szintjei – személyes, társadalmi és kormányzattal kapcsolatos értékrend – közötti összefüggések feltárására. Összehasonlítjuk, mennyire jellemzi a vállalkozói értékrend az egyes európai országok lakosságát, kiemelt figyelmet fordítva Magyarországra. Egy hazai vállalkozói adatbázis alapján megvizsgáljuk, hogy a magyar vállalkozók értékrendje eltér-e az európai átlagtól, továbbá milyen törésvonalak húzódnak a vállalkozói populáción belül az értékrend szempontjából. _____ Data from the European Values Study are used to examine what sets apart the normative views of entrepreneurs from those of other social groups in Europe about individual and state responsibility. Different levels of an individual’s value system are distinguished: personal, social and state-related values are differentiated. The interrelationships among these levels are explored. Using multivariate statistical analysis, we examine the prevalence of ‘entrepreneurial’ views in European countries, especially in Hungary. Relying on data from a survey of 300 Hungarian small entrepreneurs, we explore if their value system differs from the average value system of European entrepreneurs. Finally, we examine the factors social and economic factors that influence entrepreneurs’ views on personal and state responsibility.