Size distribution of atmospheric particulate ionic species at a coastal site in Portugal

A Berner impactor was used to collect size-differentiated aerosol samples from March to August 2003 in the city of Aveiro, on the Portuguese west coast. The samples were analysed for the main water-soluble ion species. The average concentration of sulphate, nitrate, chloride and ammonium was 6.38, 3.09, 1.67 and 1.27 µg m-3, respectively. The results show that SO4(2-) and NH4+ were consistently present in the fine fraction < 1 µm, which represents, on average, 72 and 89% of their total atmospheric concentrations, respectively. The NO3-particles were concentrated in the coarse size. Chloride presented the characteristic coarse mode for marine aerosols. During some spring/summer events, an ammonium surplus was observed (NH4+/SO4(2-) molar ratios > 2), possibly due to greater availability of ammonia coming from agricultural activities or from the neighbouring chemical industrial complex. During the remaining periods, the aerosol was found to be somewhat acidic and predominantly in the form of ammonium bisulphate (NH4+/SO4(2-) molar ratios = 0.5-1.25). Samples collected under a major or exclusive influence of maritime air masses were essentially constituted by coarse particles with enrichment in sea salt, while for air masses of continental origin the contribution of water-soluble ionic species in the fine mode was more pronounced.

Morfologia de conídios e patogenicidade de isolados de Exserohilum turcicum da Argentina e do Brasil em milho

A cultura do milho é uma das principais commodities da Argentina e do Brasil. Seu rendimento é reduzido por agentes nocivos, sendo um deles o fungo Exserohilum turcicum(Et)agente causal da helmintosporiose do milho.O presente trabalho teve como objetivo comparar as características morfológicas dos conídios e a patogenicidade de dez isolados de Etobtidos da Argentina e do Brasil. Cinco isolados monospóricos de cada país foram cultivados em meio lactose caseina hidrolizada ágar (LCHA) durante 15 dias a 25+2ºC e na ausência de luz. Prepararam-se lâminas microscópicas para a mensuração de 200 conidios de cada isolado. Na média os conídios mediram 10-25 x 30-135 μm, apresentando 2-8 septos. Detectaram-se diferenças estatísticas (p= 0,05) entre os dez isolados de Etpara todas as variáveis medidas (comprimento, largura e número de septos). Apesar da variação, as características mensuradas coincidiram com as registradas na literatura. Na comprovação da patogenicidade, plantas do híbrido de milho Pioneer P1630H, de conhecida suscetibilidade a Et, foram inoculadas com a deposição de 0,5 mL de uma suspensão de conídios de Etna concentração de 5x104 conídios/mL, no cartucho, quando atingiram a quarta folha expandida.Os dez isolados produziram, após os 15 dias da inoculação, uma média de 2,5 lesões/folha; de 39,7 x 3,4 mm de comprimento e largura respetivamente; e 4% de severidade estimada. Não se observou diferenças significativas na patogenicidade dos dez isolados estudados para nenhum dos critérios patométricos. Houve diferenças morfológicas entre os isolados da Argentina e do Brasil, porém não quanto à patogenicidade. Confirma-se que os isolados utilizados neste trabalho pertencem à espécie Et.

Exportação brasileira de papel e celulose: sua dinâmica pela equação gravitacional

O Brasil figura entre os principais produtores de celulose e papel e a indústria brasileira é mundialmente competitiva no setor. Com interesses voltados para este cenário, aplicou-se neste estudo a equação de gravidade, usada para explicar de maneira empírica fluxos de comércio entre países, com objetivo de analisar a dinâmica da exportação de papel e de celulose pelo Brasil no período de 1997 a 2005. O modelo gravitacional foi adaptado e suas variáveis explicativas foram: PIB do Brasil, PIB do país importador, PIB per capita do país importador e distância entre o importador e o Brasil. Os resultados mostraram que a distância influenciou negativamente as exportações de papel, mas ao contrário do esperado, seu coeficiente associado apresentou valor positivo para a exportação de celulose. O PIB per capta dos países importadores teve contribuição positiva para as exportações de celulose e negativa para as de papel. Tanto o PIB do Brasil, quanto o PIB dos países importadores tiveram seus coeficientes associados apresentando valor positivo, como esperado. Concluiu-se que o modelo obteve êxito na predição dos fluxos bilaterais do comércio das commodities em análise. As exportações, tanto de papel quanto de celulose, foram mais sensíveis a variações no PIB do Brasil do que a variações no PIB, PIB per capita e na distância dos países importadores. A distância influencia negativamente as exportações de papel, mas não as da celulose brasileira.

Matching salt intake to physiological need in rats using foraging protocols

Several studies of the quantitative relationship between sodium need and sodium intake in rats are reviewed. Using acute diuretic treatment 24 h beforehand, intake matches need fairly accurately when intake is spread out in time by using a hypotonic solution of NaCl. In contrast, using a hypertonic solution, intake is typically double the need. Using the same diuretic treatment, although the natriuresis occurs within ~1 h, the appetite appears only slowly over 24 h. Increased plasma levels of aldosterone parallel the increased intake; however, treatment with metyrapone blocks the rise in aldosterone but has no effect on appetite. Satiation of sodium appetite was studied in rats using sodium loss induced by chronic diuretic treatment and daily salt consumption sessions. When a simulated foraging cost was imposed on NaCl access in the form of a progressive ratio lever press task, rats showed satiation for NaCl (break point) after consuming an amount close to their estimated deficit. The chronic diuretic regimen produced hypovolemia and large increases in plasma aldosterone concentration and renin activity. These parameters were reversed to or toward non-depleted control values at the time of behavioral satiation in the progressive ratio protocol. Satiation mechanisms for sodium appetite thus do appear to exist. However, they do not operate quantitatively when concentrated salt is available at no effort, but instead allow overconsumption. There are reasons to believe that such a bias toward overconsumption may have been beneficial over evolutionary time, but such biasing for salt and other commodities is maladaptive in a resource-rich environment.

Biochemical and color changes of fresh-cut melon (Cucumis melo L. cv. Galia) treated with UV-C

The importance of minimally processed commodities in the retail groceries of most developed countries has been rising continuously during the last decades. Cantaloupe melon is used more than any other fruit in fresh-cut processing. Ultraviolet (UV) light has been extensively used to simulate biological stres in plants and for determining resistance mechanisms of plant tissues. In this study the effect of ultraviolet irradiation on some properties of fresh-cut cantalope melon was determined during storage. Freshly cut cantalope melons cubes treated with ultraviolet irradiation at the doses of 1, 2 or 3 min before storage, and then placed in a cold room at 5±1°C temperature and 85-90% RH. Hue angle values of control group is low compared to UV-C treated samples, whereas L values of is high. EL of UV treated samples higher than those of control group. Total soluble solids of fresh-cut melon samples in UC3 treatment increased during storage. The results indicate that UV-C treatments on fresh-cut cantaloupe melon cubes increased total soluble solids independently from water loss.

Mudança em tempos de globalização: o capitalismo não é mais progressista?

Technical progress and economic development are promotions of capitalism, says a well known idea hereby contradicted. Recent changes under neoliberalism show that the more freedom of move to capital the less development of productive forces. There was no synchronicity and coherence fostering economic growth between changes at the micro level of techno-productive and managerial innovations and the ones at the macro level of institutional structures and economic policy. Empowerment of finance capital and monopolies got them opportunity to control the state and set its economic policy to support fictitious capital accumulation and to rule restructuring of corporate management. Surplus redistribution favoring finance capital is a burden to be carried on the back of society's productive structures, lowering investment, employment and growth. Focusing Latin America and Brazil, the same picture is seen, worsened by external fragility that deepens historical dependency.

Para superar el estancamiento económico en México: "nudos críticos" de un proyecto nacional de desarrollo

This article is devoted to analyze changes in economic policy to be adopted by Mexico if a national development project were implemented. Starting from an evaluation of the main economic and political outcomes of Vicente’s Fox administration, the author proposes an alternative development strategy which permits Mexico to overcome economic stagnation. That strategy would be based in recovering the internal market as the dynamical focus of the economy with the purpose of satisfying basic needs of people. To be successful this strategy should to confront the "critical knots" of the Neo-liberal model: to reverse the uneven distribution of income; abandoning the fixing of restrictive monetary, fiscal and exchange rate policies; and mobilizing economic surplus by means of a profound revision of debt service schemes. It concludes that to implement a national development project it is required a political and economic strategy to dismantle neoliberalism, which is an antinational structure of power.

Os limites da participação dos trabalhadores nos ganhos das empresas

This article argues that workers’ share in profits are actually a share in extra surplus value obtained by means of more intensified labor. Cost reductions obtained by means of more intensified lean production methods cause wages to represent a smaller fraction of the product of a working day when measured at market value. The increased market rate of surplus value is the basis for workers’ shares in profits. However, as competition continuously levels out such advantages, the share in profits becomes dependent on a continuous strive to reducing costs and intensifying labor.

The Dutch disease and its neutralization: a Ricardian approach

The Dutch disease is a major market failure originated in the existence of cheap and abundant natural or human resources that keep overvalued the currency of a country for an undetermined period of time, thus turning non profitable the production of tradable goods using technology in the state-of-the-art. It is an obstacle to growth on the demand side, because it limits investment opportunities. The severity of the Dutch disease varies according to the extent of the Ricardian rents involved, i.e., according to the difference between two exchange rate equilibriums: the ‘current’ or market rate and the ‘industrial’ rate - the one that make viable efficient tradable industries. Its main symptoms, besides overvalued currency, are low rates of growth of the manufacturing industry, artificially high real wages, and unemployment. Its neutralization requires managing the exchange rate. The principal instrument for that is a sales or export tax on the commodities that give origin to the Dutch disease. In order to neutralize it policymakers face major political obstacles since it involves taxing exports and reducing wages. Finally, this papers argues that there is an extended concept of Dutch disease: besides having its origin in natural resources, it may arise from cheap labor provided that the ‘wage spread’ in the developing country is considerably larger than in the developed one - a condition that is usually present.

Matemática agradável

This paper suggests a reconsideration of the principle that public deficits should be financed by public debt. Two main reasons are offered. First, it is admitted that public debt is an economic variable whose time behaviour is better described by a first difference equation instead of an accounting identity. The convergence condition thus obtained requires either a nominal negative interest rate or that government bonds are used to raise tax income, hypotheses not theoretically granted. As a consequence, if primary surplus is not sufficient to match interests' payment, it will be observed an explosive trend in the public debt, the due interests and the money issuing. Therefore, it lacks support to the idea that public debt prevents inflation. Second, it is shown that financing public deficit through money issuing leads to a stable equilibrium money stock. The general conclusion is that, in order to simultaneously promote economic growth and inflation control, money issuing is preferable to public debt.

Globalization, nation-state and catching up

Globalization and nation-states are not in contradiction, since globalization is the present stage of capitalist development, and the nation-state is the territorial political unit that organizes the space and population in the capitalist system. Since the 1980s, Global Capitalism constitutes the economic system characterized by the opening of all national markets and a fierce competition between nation-states. Developing countries tend to catch up, while rich countries try to neutralize such competitive effort, using globalism as an ideology, and conventional orthodoxy as a strategy. Middle-income countries that are catching up in the realm of globalization are the ones that count with a national development strategy. This is broadly the case of the dynamic Asian countries. In contrast, Latin American countries have no longer their own strategy, and grow less. To add data to the argument, the author conducts an econometric test comparing these two groups of countries, and three variables: the rate of investment, the current account deficit or surplus that would indicate or not a competitive exchange rate, and public deficit.

Dívida pública, poupança em conta corrente do governo e superávit primário: uma análise de sustentabilidade

On this paper, we propose a change in the primary surplus' target by the government current account saving. That concept excludes public investment from primary surplus. However, of that change has raised a question about if government current account saving represents a sustainable fiscal policy. Thus, this paper analyses if the change in the primary surplus' target by the government current account saving implies a meaning modification on the debt-to-GDP ratio path. The empirical analysis, which is based on Brazilian monthly data for the period 1999-2005, suggests that the change in fiscal target does not mean a lack of sustain-ability.

The new international financial crisis: causes, consequences and perspectives

The paper investigates the recent financial crisis within a historical and comparative perspective having in mind that it is ultimately a confidence crisis, initially associated to a chain of high risk loans and financial innovations that spread thorough the international system culminating with impressive wealth losses. The financial market will eventually recover from the crisis but the outcome should be followed by a different and more disciplined set of international institutions. There will be a change on how we perceive the widespread liberal argument that the market is always efficient, or at least, more efficient than any State intervention, overcoming the false perception that the State is in opposition to the market. A deep financial crisis brings out a period of wealth losses and an adjustment process characterized by price corrections (commodities and equity price deflation) and real effects (recession and lower employment), and a period of turbulences and end of illusions is in place.

Celso Furtado, o retorno à polêmica fundamental

Celso Furtado, the return to the basic controversy. A reading of the work of Celso Furtado in its completion opens an enriching view of the interaction between theoretical thinking and the unveiling of Latin-America history. Starting from an appraisal of the pre-Classic and Classic authors, Furtado outlined an approach of surplus theory. That would enable development theory to deal with the unevenly industrialized economies like Brazil. His thorough analysis of development and underdevelopment processes broke away from the initial ECLA experiences to build a planning proposal the uprising country. The French roots of his academic profile helped him to keep an orderly explanation of capital demand that kept him siding with Wicksell against the subjective theory of Schumpeter.

Taxa de câmbio, exportações e crescimento: uma investigação sobre a hipótese de doença holandesa no Brasil

This paper investigates the hypothesis of Dutch disease in Brazil by the existence of a negative relationship between commodity exports and the real exchange rate, and the effects of export specialization in commodities on the Brazilian economic growth from 1999 to 2010 based on VAR model. The evidences suggested an expressive importance of commodities exports in explaining the real exchange rate changes. Moreover, commodities exports shocks were relevant to explain Brazilian economic growth rate changes, which supports the "curse" of natural resources literature.