Global runoff routing with the hydrological component of the ECMWF NWP system

A global river routing scheme coupled to the ECMWF land surface model is implemented and tested within the framework of the Global Soil Wetness Project II, to evaluate the feasibility of modelling global river runoff at a daily time scale. The exercise is designed to provide benchmark river runoff predictions needed to verify the land surface model. Ten years of daily runoff produced by the HTESSEL land surface scheme is input into the TRIP2 river routing scheme in order to generate daily river runoff. These are then compared to river runoff observations from the Global Runoff Data Centre (GRDC) in order to evaluate the potential and the limitations. A notable source of inaccuracy is bias between observed and modelled discharges which is not primarily due to the modelling system but instead of to the forcing and quality of observations and seems uncorrelated to the river catchment size. A global sensitivity analysis and Generalised Likelihood Uncertainty Estimation (GLUE) uncertainty analysis are applied to the global routing model. The ground water delay parameter is identified as being the most sensitive calibration parameter. Significant uncertainties are found in results, and those due to parameterisation of the routing model are quantified. The difficulty involved in parameterising global river discharge models is discussed. Detailed river runoff simulations are shown for the river Danube, which match well observed river runoff in upstream river transects. Results show that although there are errors in runoff predictions, model results are encouraging and certainly indicative of useful runoff predictions, particularly for the purpose of verifying the land surface scheme hydrologicly. Potential of this modelling system on future applications such as river runoff forecasting and climate impact studies is highlighted. Copyright © 2009 Royal Meteorological Society.

Following the creation of active gold nanocatalysts from phosphine-stabilized molecular clusters

The phosphine-stabilised gold cluster [Au6(Ph2P-o-tolyl)6](NO3)2 is converted into an active nanocatalyst for the oxidation of benzyl alcohol through low-temperature peroxide-assisted removal of the phosphines, avoiding the high-temperature calcination process. The process was monitored using in-situ X-ray absorption spectroscopy, which revealed that after a certain period of the reaction with tertiary butyl hydrogen peroxide, the phosphine ligands are removed to form nanoparticles of gold which matches with the induction period seen in the catalytic reaction. Density functional theory calculations show that the energies required to remove the ligands from the [Au6Ln]2+ increase significantly with successive removal steps, suggesting that the process does not occur at once but sequentially. The calculations also reveal that ligand removal is accompanied by dramatic re-arrangements in the topology of the cluster core.

Impegno nero: Italian intellectuals and the African-American struggle

In the aftermath of the Second World War, Italian intellectuals participated in Italy’s reconstruction with an ideological commitment inspired by the African-American struggle for equal rights in the United States. Drawing on the work of many of the leading figures in postwar Italian culture, including Italo Calvino, Giorgio Caproni, Cesare Pavese, and Elio Vittorini, this essay argues that Italian intellectual impegno—defined as the effort to remake Italian culture and to guide Italian social reform—was united with a significant investment in the African-American cause. The author terms this tendency impegno nero and traces its development in the critical reception of African-American writers including W.E.B. DuBois, Langston Hughes, and Richard Wright. Postwar impegno nero is then contrasted with the treatment of African-American themes under Fascism, when commentators had likewise condemned American racism, but had paradoxically linked their laments for the plight of African Americans with defenses of the racial policies of the Fascist regime. Indeed, Fascist colonialism and anti-Semitism were both justified through references to what Fascist intellectuals believed to be America’s greater injustices. After 1945, in contrast, Italian intellectuals advocated an international, interdependent campaign for justice, symbolizing national reforms by projecting them onto an emblematic America. In this way, impegno nero revived and revised the celebrated "myth of America" that had developed in Italy between the world wars. Advancing a new, postwar myth, Italian intellectuals adopted the African-American struggle in order to reinforce their own efforts in the ongoing struggle for justice in Italy.

Modulation of equatorial Pacific westerly/easterly wind events by the Madden-Julian oscillation and convectively-coupled Rossby waves

Synoptic wind events in the equatorial Pacific strongly influence the El Niño/Southern Oscillation (ENSO) evolution. This paper characterizes the spatio-temporal distribution of Easterly (EWEs) and Westerly Wind Events (WWEs) and quantifies their relationship with intraseasonal and interannual large-scale climate variability. We unambiguously demonstrate that the Madden–Julian Oscillation (MJO) and Convectively-coupled Rossby Waves (CRW) modulate both WWEs and EWEs occurrence probability. 86 % of WWEs occur within convective MJO and/or CRW phases and 83 % of EWEs occur within the suppressed phase of MJO and/or CRW. 41 % of WWEs and 26 % of EWEs are in particular associated with the combined occurrence of a CRW/MJO, far more than what would be expected from a random distribution (3 %). Wind events embedded within MJO phases also have a stronger impact on the ocean, due to a tendency to have a larger amplitude, zonal extent and longer duration. These findings are robust irrespective of the wind events and MJO/CRW detection methods. While WWEs and EWEs behave rather symmetrically with respect to MJO/CRW activity, the impact of ENSO on wind events is asymmetrical. The WWEs occurrence probability indeed increases when the warm pool is displaced eastward during El Niño events, an increase that can partly be related to interannual modulation of the MJO/CRW activity in the western Pacific. On the other hand, the EWEs modulation by ENSO is less robust, and strongly depends on the wind event detection method. The consequences of these results for ENSO predictability are discussed.

Random primordial magnetic fields and the gas content of dark matter haloes

We recently predicted the existence of random primordial magnetic fields (RPMFs) in the form of randomly oriented cells with dipole-like structure with a cell size L(0) and an average magnetic field B(0). Here, we investigate models for primordial magnetic field with a similar web-like structure, and other geometries, differing perhaps in L(0) and B(0). The effect of RPMF on the formation of the first galaxies is investigated. The filtering mass, M(F), is the halo mass below which baryon accretion is severely depressed. We show that these RPMF could influence the formation of galaxies by altering the filtering mass and the baryon gas fraction of a halo, f(g). The effect is particularly strong in small galaxies. We find, for example, for a comoving B(0) = 0.1 mu G, and a reionization epoch that starts at z(s) = 11 and ends at z(e) = 8, for L(0) = 100 pc at z = 12, the f(g) becomes severely depressed for M < 10(7) M(circle dot), whereas for B(0) = 0 the f(g) becomes severely depressed only for much smaller masses, M < 10(5) M(circle dot). We suggest that the observation of M(F) and f(g) at high redshifts can give information on the intensity and structure of primordial magnetic fields.

Aprendizagem organizacional num processo de consolidação do treinamento e desenvolvimento de competências

O contexto atual das organizações requer mudanças constantes e também novas habilidades, as quais em nada lembram as organizações do passado, marcadas por uma visão mecanicista. Nas organizações modernas, a aprendizagem tornou-se fundamental e imprescindível para a sobrevivência. O setor de Treinamento, enquanto subsistema da área de Recursos Humanos, pode ser um excelente mediador da aprendizagem. No entanto, o dia-a-dia das organizações revela uma grande lacuna entre o que se investe em treinamento e o que se aplica na prática, ou seja, não há uma consolidação dos treinamentos e os resultados ficam aquém do esperado. Diante desta problemática busca-se, então, avaliar o Programa de Desenvolvimento de Gestores (PDG) da Cameco do Brasil Ltda. em relação à abordagem da Aprendizagem Organizacional, considerando-se a consolidação do treinamento e o desenvolvimento de competências. Entende-se relevante analisar este programa sob à luz da abordagem da Aprendizagem Organizacional, por ser uma abordagem que propõe diferentes formas de desenvolver a capacidade de aprendizagem das organizações. O programa de treinamento, no caso: Programa de Desenvolvimento de Gestores ( PDG), objeto de estudo desta dissertação, é parte de um programa maior 9 da empresa – o Programa de Educação Continuada. Os participantes do PDG são funcionários que estão em cargos de supervisão ou estão sendo preparados para assumir novas funções no futuro. O método utilizado para investigação é de natureza qualitativa, apresentado sob a estratégia de estudo de caso em uma única empresa, elaborado com base em entrevistas semi-diretivas e observação participante. Para fins de interpretação dos resultados, utilizou-se análise de conteúdo, sendo que as unidades de análise foram elaboradas e agrupadas de acordo com o tema. Num primeiro momento foi efetuada uma pré-análise e após, realizou-se a interpretação dos resultados à luz de alguns pressupostos teóricos da Aprendizagem Organizacional que embasaram as categorias de análise. Os resultados da pesquisa apontam para o fato de que transformar o treinamento em ações aplicáveis dentro da organização requer profundas mudanças na maneira de pensar e agir, o que não parece ter ocorrido na situação da empresa pesquisada. Uma infra-estrutura adequada, por parte da empresa, no sentido de apoiar este tipo de programa é fundamental. Em contrapartida, se as pessoas não possuem um interesse genuíno em aprender, nem sentem de que forma suas vidas serão afetadas com isso, definitivamente, nenhum programa terá bons resultados. Na empresa em questão parece ter faltado, justamente, este elo de ligação entre os interesses individuais e os interesses da empresa, bem como um método de acompanhamento de todo o processo por parte de RH. Para isso, um processo de mudança planejada é proposto, onde RH deve assumir novos papéis.

Determinantes da liquidez nas empresas: uma investigação das especificidades brasileiras

Este estudo teve como objetivo investigar se algumas situações específicas do Brasil podem contribuir para que as empresas apresentem índices de liquidez ainda maiores, tais como a possibilidade de captação de recursos de baixo custo e aplicação à taxas mais altas e a existência de fatores que resultam na discrepância entre lucro e geração de caixa das companhias. Foram examinadas as proxies para estas situações através de um estudo em painel com 288 empresas não financeiras de capital aberto no período de 1997 a 2006 com a inclusão de outras variáveis que explicam as variações no nível de liquidez relacionadas aos motivos de precaução, transação, especulação e assimetria de informação. Os principais resultados sugerem que o nível de liquidez nas firmas brasileiras é maior nas empresas que possuem algum tipo de benefício fiscal e/ou conseguem financiamentos a custos reduzidos, medido pela acessibilidade a outros mercados para captação de recursos (dummy ADR).

Tabela periódica

Este item é parte de um conjunto de modelos produzido pela equipe do Laboratório de Objetos de Apredizagem (LOA)/UFSCar para o jogo LabTecA

Leadership of portuguese community schools in the East Coast of the United States and the public policies of education: a multiple case studies

The Portuguese community schools of the United States located in the areas of larger Portuguese population concentration are social organizations that come materializing throughout decades the designs of the educative policies of the Portuguese government in relation to the expansion and preservation of the language, the culture and the history of Portugal. These designs of the educative policies are enrolled in the Constitution of the Republic (1976), in the Basic Law of Educative System (1986) and, over all, in the successive legislative norms (Decree-laws and ordinances) of the successive governments. Portuguese community schools in the United States are structuralized in analogous way to schools of the Portuguese geographic space. For this qualitative study (multiple case), four directors of Portuguese schools of the East Coast of the United States were interviewed; two schools are in the state of Rhode Island and the other two are in the state of Massachusetts. Also, it was administered the questionnaire on practices of leadership “Leadership Practices Inventory” (LPI) of Kouzes and Posner (2002) to collect additional data about practices of leadership on the directors of the schools. The LPI evaluates practices of leadership classifying them in five domains: (a) Model the way; (b) Inspire a shared vision; (c) Challenge the process; (d) Enable others to act; and, (e) Encourage the heart. Results of this qualitative research indicate that the Portuguese Government has not had an educative policy stimulant, coherent and consistent of support, incentive, maintenance and diffusion of the Portuguese language and culture and the directors of the studied schools they have a proactive and serving leadership style in conducting the management of Portuguese community schools. The five practices of leadership are highly practiced by the directors of the studied schools above all the practices “Enable others to act” and “Encourage the heart”.

Biology of Plutella xylostella L. (Lepidoptera: Plutellidade) Reared on Cauliflower Genotypes

This work was conducted to evaluate biological parameters of Plutella xylostella L. reared on leaves of several cauliflower genotypes under laboratory conditions. The experiment was set in a randomized block design and arranged in a 6 x 2 factorial (genotypes x generations). Leaf disks of the cultivars Barcelona, Verona, Piracicaba Precoce, Sharon, Silver Streak, and Teresopolis Gigante were placed in Petri dishes with 12 newly-hatched larvae. Leaf disks were initially changed after the fourth day, but daily afterwards until the larvae reached the pupal stage. The same procedure was adopted for the second generation. Twenty adults of each sex were separated from each genotype to evaluate their longevity, and I 0 couples from each treatment were used to assess female fecundity. The lowest larval survival was obtained on the 'Silver Streak' (78.9%) and highest on 'Verona' (97.1%). The 'Silver Streak' and `Teresopolis Gigante' showed the lowest pupal weights (4.83 mg and 5.11 mg, respectively), as well as the lowest fecundity, 119.4 and 123.0 eggs/female, respectively, while 'Piracicaba Precoce' the highest (167.7 eggs/female). Males obtained from larvae reared on `Teresopolis Gigante' and 'Silver Streak' lived shorter (5.1 days), while the short-lived females were obtained from larvae reared on 'Barcelona' and 'Verona' (4.9 and 5.0 days). Insect development was prolonged in the second generation in all tested genotypes.

Manejo químico de espécies de trapoeraba com aplicação isolada e em mistura de diferentes herbicidas

This paper evaluated the effect of different herbicides applied isolated and mixed on two species of dayflower (Commelina benghalensis and Commelina villosa). Both species were grown under pot conditions with a capacity of 14 L. Three stems with 10 cm were planted per pot. The herbicides application was made using a stationary spray system, to provide a spray volume of 200 L ha(-1), with spray tip XR 110.02VS, when the plants were with dimensions of 25-35 cm for C. benghalensis and 30-35 cm for C. villosa. The mixture saflufenacil more effective control of C. benghalensis were saflufenacil + glyphosate (48 + 720 g ha(-1)) and, saflufenacil + (glyphosate + imazethapyr) with and without the addition of ammonium sulfate (24 + 623 g ha(-1)). The combination of carfentrazone + glyphosate (20 + 720 g ha(-1)) were also effective in the C. benghalensis control. The saflufenacil mixture allowed plant control of C. villosa, where saflufenacil + glyphosate (24 + 720 g ha(-1)) with the addition of ammonium sulfate, showed a good visually control of this species. The application of 2,4-D (720 g ha(-1)) and 2,4-D + glyphosate (720 + 720 g ha(-1)) provided the best visual controls of C. benghalensis e C. villosa. All chemical treatment regardless of Commelina species reduced the dry mass of dayflower.

Efeitos da suplementação de fitase sobre a disponibilidade aparente de Mg, Ca, Zn, Cu, Mn e Fe em alimentos vegetais para a tilápia-do-nilo

Cem juvenis de tilápia-do-nilo (Oreochromis niloticus; PV = 100.0 ± 5.0 g) foram distribuídos em 10 tanques-rede com o objetivo de avaliar o efeito da suplementação da enzima fitase (0, 1.000 e 2.000 UFA/kg) sobre a disponibilidade de minerais em alguns alimentos energéticos (milho, milho extrusado, farelo de trigo, farelo de arroz e farelo de sorgo) e protéicos (farelo de soja extrusado, farelo de soja, farelo de girassol, farelo de algodão e glúten de milho) utilizados na alimentação de tilápia-do-nilo (Oreochromis niloticus). Para determinação dos coeficientes de disponibilidade aparente (CDA) do cálcio (Ca), magnésio (Mg), zinco (Zn), cobre (Cu), ferro (Fe) e manganês (Mn), foram confeccionadas 31 rações, marcadas com 0,10% de óxido de crômio III uma referência (ração purificada) e 30 contendo os dez alimentos e os diferentes níveis de suplementação da enzima fitase. O CDA dos nutrientes foi calculado com base no teor de crômio da ração e das fezes. A fitase aumenta, nos vegetais, a disponibilidade do Mg, Cu, Zn e Mn, os quais apresentam tendência diferenciada, em razão do seu valor biológico e do nível de suplementação de enzima.

Effect of red and infrared low-level laser therapy in endodontic sealer on subcutaneous tissue

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)