Arsenic toxicity in Acacia mangium willd. and mimosa Caesalpiniaefolia benth. seedlings

Acacia mangium and Mimosa caesalpiniaefolia are fast-growing woody fabaceous species that might be suitable for phytoremediation of arsenic (As)-contaminated sites. To date, few studies on their tolerance to As toxicity have been published. Therefore, this study assessed As toxicity symptoms in A. mangium and M. caesalpiniaefolia seedlings under As stress in a greenhouse. Seedlings of Acacia mangium and M. caesalpiniaefolia were grown for 120 d in an Oxisol-sand mixture with 0, 50, 100, 200, and 400 mg kg-1 As, in four replications in four randomized blocks. The plants were assessed for visible toxicity symptoms, dry matter production, shoot/root ratio, root anatomy and As uptake. Analyses of variance and regression showed that the growth of A. mangium and M. caesalpiniaefolia was severely hindered by As, with a reduction in dry matter production of more than 80 % at the highest As rate. The root/shoot ratio increased with increasing As rates. At a rate of 400 mg kg-1 As, whitish chlorosis appeared on Mimosa caesalpiniaefolia seedlings. The root anatomy of both species was altered, resulting in cell collapse, death of root buds and accumulation of phenolic compounds. Arsenic concentration was several times greater in roots than in shoots, with more than 150 and 350 mg kg-1 in M. caesalpiniaefolia and A. mangium roots, respectively. These species could be suitable for phytostabilization of As-contaminated sites, but growth-stimulating measures should be used.

Mecanismo de fotodegradação de compostos orgânicos catalisada por TiO2

Conventional technology used in the treatment of wastewater has been pointed as a major environmental problem for sustainable development, since minimization is not addressed accordingly. Advanced oxidation processes (AOP), based on the formation of hydroxyl radical (•OH), a powerful oxidant agent, have been considered to be a potential technology for the destruction of many toxic compounds. Photocatalysis using solar light, an AOP, has been studied for nearly 20 years and recently attracted great interest as a clean-up technology. However, solar detoxification processes have not yet achieved commercial success. This article presents an overview of reaction mechanisms at the surface of semiconductors used as photocatalysts (specially TiO2), when heterogeneous photocatalysis is used to remove hazardous compounds from contaminated sites.

Uso do bivalve límnico Anodontites tenebricosus (LEA, 1834) no biomonitoramento de metais do Rio Ribeira de Iguape

This study investigated the contamination of the Ribeira de Iguape River - RIR by Cd, Zn, Cr and Pb, using the bivalve Anodontites tenebricosus as a biomonitor. Metal concentrations in tissue samples were measured by HR-ICPMS. Bivalve tissues exhibited mean levels of 1.00 µg/g Cd; 152.89 µg/g Zn; 14.79 µg/g Cr and 4.40 µg/g Pb. Lead concentrations were comparable to those reported for moderately contaminated sites. The results showed that Pb is bioavailable to the bivalves, exhibiting high concentrations and exceeding both natural and reference values for human consumption. The freshwater bivalve Anodontites tenebricosus is a suitable biomonitor of contamination by metals.

Zinc accumulation in phosphate granules of Ucides cordatus hepatopancreas

Amorphous phosphate granules are present in vertebrate and invertebrate organisms. The functions attributed to these structures depend on their mineral contents and organic matrix composition. In the present study we have determined zinc concentrations in the hepatopancreas of the crab Ucides cordatus from regions contaminated with zinc, and the elemental composition of hepatopancreal phosphate granules. Organisms were collected from the contaminated areas of Sepetiba Bay (SB) and Guanabara Bay (GB), and from a non-contaminated area, Ribeira Bay (RB). The first two sites are located near the metropolitan region of Rio de Janeiro city, Brazil. Atomic absorption spectroscopy (AAS) showed a significant difference (P<0.05) for zinc concentration in the hepatopancreas from organisms collected at the contaminated sites GB (210 ± 20 µg/g dry weight) and SB (181 ± 16 µg/g dry weight) compared to the non-contaminated site RB (76 ± 14 µg/g dry weight). Phosphate granules isolated from hepatopancreatic tissue were studied by electron diffraction (ED), energy dispersive X-ray analysis (EDX) and electron spectroscopic imaging (ESI). ED of granules presented no diffraction spots, indicating that these structures are in an amorphous state, while EDX of granules isolated from a contaminated area contained P, Ca and Zn. Mg, Cl and Fe were also found in some of the spectra. ESI showed that O, P and Ca were colocalized in the mineralized layers of most granules observed. The correlation between the results obtained by AAS and those obtained by microanalytical techniques suggests that the hepatopancreatic granules of U. cordatus may be related to the phenomenon of heavy metal retention.

Avaliação das informações sobre rinite alérgica em sites brasileiros na rede mundial de computadores (Internet)

A rede mundial de computadores (Internet) é, atualmente, fonte de informação sobre saúde para leigos e profissionais da área médica. A Rinite Alérgica é uma doença muito prevalente que chega a atingir mais de 10% da população geral, causando queda da qualidade de vida. OBJETIVO: Avaliar os princípios éticos de sites brasileiros que divulgam informações a respeito do tema "rinite alérgica". FORMA DE ESTUDO: revisional. MATERIAL E MÉTODO: Foi feita avaliação de 173 sites brasileiros encontrados através de quatro mecanismos de busca (Google, Yahoo, Altavista e Radar Uol). Os sites foram avaliados de acordo com o Manual de Princípios Éticos para Sites de Medicina e Saúde do CREMESP (Conselho Regional de Medicina do Estado de São Paulo), de acordo com os itens transparência, honestidade, qualidade, consentimento livre e esclarecido, privacidade, ética médica, responsabilidade e procedência. RESULTADOS: Entre os sites analisados, 149 (86,1%) não estavam de acordo como Manual de Princípios Éticos para Sites de Medicina e Saúde do CREMESP. As proporções de irregularidades entre os itens avaliados foram: qualidade (84,4%), privacidade (46,2%) honestidade (18,5%), consentimento livre e esclarecido (15,6%), responsabilidade (13,9%), transparência (12,1%), ética médica (2,3%). Havia informações inexatas em 24,3% dos sites analisados. CONCLUSÕES: A maioria dos sites estudados contendo informações sobre rinite alérgica fere os princípios éticos para sites do CREMESP. Tanto a qualidade em geral de grande parte dos sites brasileiros que abordam o tema "rinite alérgica", quanto à qualidade das informações por eles divulgadas, são insuficientes para satisfazer a médicos e pacientes.

Os sites dos ministérios de relações exteriores no mundo e a História

A Internet é aqui considerada uma fonte alternativa do estudo da história, sobretudo história das relações diplomáticas. São analisados os sites dos ministérios das relações exteriores pelo mundo: alguns atribuem grande importância à história, com detalhada visão retrospectiva (Brasil, França, México, Rússia, Alemanha, Estados Unidos), outros têm abordagem seletiva ou restrita a determinados períodos (Espanha, Argentina, Itália, Bélgica, Portugal, China, Japão), uns se voltam para o passado, somente com informações históricas que sejam indispensáveis à imagem nacional (Suíça) e outros mostram sua história voltada para o futuro (Grã-Bretanha).

Going Global: an organizational study of Brazilian foreign policy

This study analyzes the impact of globalisation on the organization and strategies outlined by the Brazilian Ministry of Foreign Affairs. The study intends to understand how countries from the periphery deal with new institutional challenges resulting from globalization, using the case of the Brazilian diplomatic service.

Brazilian foreign policy towards South America during the Lula administration: caught between South America and Mercosur

The aim of this article is to analyze Brazil's foreign policy towards the South American region during President Lula's administration. As such, the article intends to highlight two specific dimensions: the extent to which foreign policy during this period has differed from previous periods and the relative importance granted by Brazilian diplomacy to recent cooperation and integration efforts, more specifically the Unasur and Mercosur. The article argues that the Lula administration has behaved differently from its predecessors by prioritizing the building up of Brazilian leadership in South America on several different fronts, especially by strengthening multilateral institutions in the region

The new Africa and Brazil in the Lula era: the rebirth of Brazilian Atlantic Policy

In the post-Cold War world, Africa has been an important focus of Brazilian foreign policy. Having a significant historical weight in building our nation, African countries are also part of the moves adopted by Brazil's foreign policy. The main purpose of the present text is to show this relevant regional dimension regarding Brazil's international insertion during the Lula era. The work is divided in two parts: the first part approaches Africa's international insertion throughout recent years and the second analyses the dimension occupied by African affairs in Brazil during the Lula era. The main argument is that the new role played by Africa in the international scene coincides with a global Brazil

Brazilian foreign policy under President Lula (2003-2010): an overview

Foreign Minister of Brazil since 2003, Ambassador Celso Amorim outlines the main guidelines and accomplishments of Brazil's foreign policy under President Luiz Inácio Lula da Silva. The article provides a full-fledged, although not exhaustive, narrative of a number of diplomatic initiatives championed by Brazil over the last eight years: from the gathering of the group of developing countries in a World Trade Organization (WTO) meeting in Cancun to the negotiations that led to the Declaration of Tehran, as well as the challenges the country has been facing as its international weight grows.

Climate paradox of the G-8: legal obligations, policy declarations and implementation gap

This article analyzes the climate policy performance of the G-8 from 1992 to 2012 based on their legal commitments (Annex-1 and Annex-B countries) under the UNFCCC (1992) and the Kyoto Protocol (1997) and their policy declarations on their GHG reduction goals until 2050. A climate paradox has emerged due to a growing implementation gap in Canada, USA and Japan, while Russia, Germany, UK, France and Italy fulfilled their GHG reduction obligation.

An overview of domestic aspects in US climate policy

The article shows how domestic aspects influence the United States national and international climate policy. To accomplish the task, the authors analyzes the discussions when Bill Clinton was ruling the country, a time during which global discussions were forwarded. The paper recalls the debate in the Bush administration and the growing polarization since Barack Obama took office.