711 resultados para 1075


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University of Illinois bookplate: "From the library of Conte Antonio Cavagna Sangiuliani di Gualdana Lazelada di Bereguardo purchased 1921".

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Mode of access: Internet.

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Includes indexes.

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The Baltic Sea is a unique environment as the largest body of brackish water in the world. Acidification of the surface oceans due to absorption of anthropogenic CO2 emissions is an additional stressor facing the pelagic community of the already challenging Baltic Sea. To investigate its impact on trace gas biogeochemistry, a large-scale mesocosm experiment was performed off Tvärminne Research Station, Finland in summer 2012. During the second half of the experiment, dimethylsulphide (DMS) concentrations in the highest fCO2 mesocosms (1075-1333 µatm) were 34 % lower than at ambient CO2 (350 µatm). However the net production (as measured by concentration change) of seven halocarbons analysed was not significantly affected by even the highest CO2 levels after 5 weeks exposure. Methyl iodide (CH3I) and diiodomethane (CH2I2) showed 15 % and 57 % increases in mean mesocosm concentration (3.8 ± 0.6 pmol L-1 increasing to 4.3 ± 0.4 pmol L-1 and 87.4 ± 14.9 pmol L-1 increasing to 134.4 ± 24.1 pmol L-1 respectively) during Phase II of the experiment, which were unrelated to CO2 and corresponded to 30 % lower Chl-? concentrations compared to Phase I. No other iodocarbons increased or showed a peak, with mean chloroiodomethane (CH2ClI) concentrations measured at 5.3 (± 0.9) pmol L-1 and iodoethane (C2H5I) at 0.5 (± 0.1) pmol L-1. Of the concentrations of bromoform (CHBr3; mean 88.1 ± 13.2 pmol L-1), dibromomethane (CH2Br2; mean 5.3 ± 0.8 pmol L-1) and dibromochloromethane (CHBr2Cl, mean 3.0 ± 0.5 pmol L-1), only CH2Br2 showed a decrease of 17 % between Phases I and II, with CHBr3 and CHBr2Cl showing similar mean concentrations in both Phases. Outside the mesocosms, an upwelling event was responsible for bringing colder, high CO2, low pH water to the surface starting on day t16 of the experiment; this variable CO2 system with frequent upwelling events implies the community of the Baltic Sea is acclimated to regular significant declines in pH caused by up to 800 µatm fCO2. After this upwelling, DMS concentrations declined, but halocarbon concentrations remained similar or increased compared to measurements prior to the change in conditions. Based on our findings, with future acidification of Baltic Sea waters, biogenic halocarbon emissions are likely to remain at similar values to today, however emissions of biogenic sulphur could significantly decrease from this region.

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O objetivo principal desta dissertação foi o de pesquisar as causas; I) das dificuldades de implementação do Novo Ensino Médio (que estabelece no currículo nacional a interdisciplinaridade como um princípio); II) das dificuldades dos professores para com o trabalho interdisciplinar; III) da resistência dos mesmos em relação a ele. O método utilizado foi o da pesquisa bibliográfica, observando-se as posições de dois grupos de pensadores quanto ao problema discutido neste trabalho. No primeiro grupo (Foucault; Nietzsche; Hockeimer da Escola de Frankfurt e Veiga-Neto) foram indicadas para a implementação dificuldades epistemológicas, enquanto, no segundo (Marx e Santos Filho), foram apresentadas políticas, econômicas e sociológicas dificuldades a serem superadas para que se atinja o objetivo almejado no projeto educacional.(AU)

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The paper describes epistemic marking in Ika (Arwako-Chibchan, Colombia) and proposes an analysis in terms of a typologically unusual pattern called conjunct/disjunct, which has been attested for a small number of Asian and South American languages. Canonically, conjunct occurs with first person subjects in statements and with second person in questions, as opposed to any other combination of subject and sentence-type, which is disjunct. The pattern found in Ika both conforms to expectations and, at the same time, contributes to a more nuanced analysis of the functional motivations of the conjunct/disjunct pattern. In Ika, conjunct marking encodes the speaker's direct access to an event that involves either (or both) of the speech participants. In addition, conjunct/disjunct marking interacts predictably with a second set of epistemic markers that encode asymmetries in the epistemic authority of the speaker and the addressee. The analysis builds on first-hand data but remains tentative, awaiting further investigation.

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In this article we aim to analyze the relationship between a set of organizational extrinsic and intrinsic factors and the adoption of the Balanced Scorecard(BSC) by privately-owned Portuguese organizations (large companies and small and médium enterprises).These factos are related to companies age,the diversity of products and services,the nature of the ownership structure,the internationalization,and the organizational size. As a primary means of data collection was carried out a postal survey through a questionnaire sent to 549 privately-owned Portuguese organizations, with na overall responserate of 28.2%. The results indicate that the degree of diversity of the products/services of the organization,the owner- ship of foreign groups,and theo rganizational size are positively associated with the implementation of the BSC.Thus,we conclude that the BSC increases with the degree of diversity of the products/services of the organization,that the Portuguese organizations that use the BSC are mainly owned by foreign groups; and larger organizations are most likely to use this tool.

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To investigate the neurotoxic effects of aluminium (Al) Al was administered: 1) in the diet of the rat (30 mg Al/kg body weight for 6 weeks); 2) as a suspension of aluminium acetate in drinking water of the rat for 3 months and 3) in a long-term study in the mouse in which aluminosilicates were incorporated into a pelleted diet (1035 mg/kg of food over 23 months). In the latter treatment, increased Al was combined with a reduction in calcium and magnesium; a treatment designed to increase absorption of Al into the body. Administration of Al in the drinking water significantly reduced total brain biopterins and BH4 synthesis. However, no significant affect of Al in the diet on total biopterins or BH4 synthesis was found either in the rat or in the long-term study in the mouse. In addition, in the mouse no significant effects of the Al diet on levels of noradrenaline, serotonin, dopamine, 5-HIAA or CAT could be demonstrated. Hence, the occurrence of brain alterations may depend on the Al species present and the method of administration. Al salts in drinking water may increase brain tissue levels compared with the administration of a more insoluble species. Since alterations in biopterin metabolism are also a feature of Alzheimer's disease (AD) these results support the hypothesis that Al in the water supply may be a factor in AD.

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We report the formation and structural properties of co-crystals containing gemfibrozil and hydroxy derivatives of t-butylamine H2NC(CH3)3-n(CH2OH)n, with n=0, 1, 2 and 3. In each case, a 1:1 co-crystal is formed, with transfer of a proton from the carboxylic acid group of gemfibrozil to the amino group of the t-butylamine derivative. All of the co-crystal materials prepared are polycrystalline powders, and do not contain single crystals of suitable size and/or quality for single crystal X-ray diffraction studies. Structure determination of these materials has been carried out directly from powder X-ray diffraction data, using the direct-space Genetic Algorithm technique for structure solution followed by Rietveld refinement. The structural chemistry of this series of co-crystal materials reveals well-defined structural trends within the first three members of the family (n=0, 1, 2), but significantly contrasting structural properties for the member with n=3. © 2007 Elsevier Inc. All rights reserved.

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A key purpose of this study is to explore the lessons learned from international retail divestment and market withdrawal experiences. Drawing on 33 in-depth interviews with leading investment banks and key retail executives at Tesco, the study investigates the company's international restructuring and divestment activities in Ireland and France during the mid -1980s and 1990s. It has been demonstrated that, despite the progressive merger and acquisition wave sweeping through the corporate retail landscape recently, international retail divestment is quite widespread. The main conclusion from this study is that Tesco originally did not envisage divestment or de-internationalisation as part of the original internationalisation strategy process in either the acquisition of Three Guys in Ireland or Catteau in France. There was no appreciation from Tesco during their early period of expansion of the fact that exit pressures might arise during the course of market entry. In this regard, the case study provides insights into the relationship between investment and divestment within the context of international retail restructuring. The case evidence also demonstrates the positive impact of the Three Guys and Catteau divestments which helped management to refocus and rejuvenate the company's internationalisation process.

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Single cell recordings in monkeys support the notion that the lateral prefrontal cortex (PFC) controls reactivation of visual working memory representations when rehearsal is disrupted. In contrast, recent fMRI findings yielded a double dissociation for PFC and the medial temporal lobe (MTL) in a letter working memory task. PFC was engaged in interference protection during reactivation while MTL was prominently involved in the retrieval of the letter representations. We present event-related potential data (ERP) that support PFC involvement in the top-down control of reactivation during a visual working memory task with endogenously triggered recovery after visual interference. A differentiating view is proposed for the role of PFC in working memory with respect to endogenous/exogenous control and to stimulus type. General implications for binding and retention mechanisms are discussed.

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Tooth enamel is the stiffest tissue in the human body with a well-organized microstructure. Developmental diseases, such as enamel hypomineralisation, have been reported to cause marked reduction in the elastic modulus of enamel and consequently impair dental function. We produce evidence, using site-specific transmission electron microscopy (TEM), of difference in microstructure between sound and hypomineralised enamel. Built upon that, we develop a mechanical model to explore the relationship of the elastic modulus of the mineral-protein composite structure of enamel with the thickness of protein layers and the direction of mechanical loading. We conclude that when subject to complex mechanical loading conditions, sound enamel exhibits consistently high stiffness, which is essential for dental function. A marked decrease in stiffness of hypomineralised enamel is caused primarily by an increase in the thickness of protein layers between apatite crystals and to a lesser extent by an increase in the effective crystal orientation angle. © 2009 Elsevier Ltd. All rights reserved.