Physiographic and floristic gradients across topography in transitional seasonally dry evergreen forests of southeast Pará, Brazil

Seasonally dry evergreen forests in southeast Pará, Brazil are transitional between taller closed forests of the interior Amazon Basin and woodland savannas (cerrados) of Brazil's south-central plains. We describe abiotic and biotic gradients in this region near the frontier town of Redenção where forest structure and composition grade subtly across barely undulating topography. Annual precipitation averaged 1859 mm between 1995-2001, with nearly zero rainfall during the dry season months of June August. Annual vertical migrations of deep-soil water caused by seasonal rainfall underlie edaphic and floristic differences between high- and low-ground terrain. Low-ground soils are hydromorphic, shaped by perching water tables during the wet season, pale gray, brown, or white in color, with coarse texture, low moisture retention during the dry season, and relatively high macro-nutrient status in the surface horizons. Forest canopies on low ground are highly irregular, especially along seasonal streams, while overstory community composition differs demonstrably from that on high ground. High-ground soils are dystrophic, well-drained through the wet season, brown or red-yellow in color, with finer texture, higher moisture retention, and low macro-nutrient status in the surface horizons compared to low-ground soils. Forest canopies are, on average, taller, more regular, and more closed on high ground. Low-ground areas can be envisioned as energy and nutrient sinks, where, because of hydrologic cycles, canopy disturbance likely occurs more frequently than at high-ground positions if not necessarily at larger scales.

Least limiting water range in assessing compaction in a Brazilian Cerrado latosol growing sugarcane

In the south-central region of Brazil, there is a trend toward reducing the sugarcane inter-harvest period and increasing traffic of heavy harvesting machinery on soil with high water content, which may intensify the compaction process. In this study, we assessed the structural changes of a distroferric Red Latosol (Oxisol) by monitoring soil water content as a function of the Least Limiting Water Range (LLWR) and quantified its effects on the crop yield and industrial quality of the first ratoon crop of sugarcane cultivars with different maturation cycles. Three cultivars (RB 83-5054, RB 84-5210 and RB 86-7515) were subjected to four levels of soil compaction brought about by a differing number of passes of a farm tractor (T0 = soil not trafficked, T2 = 2 passes, T10 = 10 passes, and T20 = 20 passes of the tractor in the same place) in a 3 × 4 factorial arrangement with three replications. The deleterious effects on the soil structure from the farm machinery traffic were limited to the surface layer (0-10 cm) of the inter-row area of the ratoon crop. The LLWR dropped to nearly zero after 20 tractor passes between the cane rows. We detected differences among the cultivars studied; cultivar RB 86-7515 stood out for its industrial processing quality, regardless of the level of soil compaction. Monitoring of soil moisture in the crop showed exposure to water stress conditions, although soil compaction did not affect the production variables of the sugarcane cultivars. We thus conclude that the absence of traffic on the plant row maintained suitable soil conditions for plant development and may have offset the harmful effects of soil compaction shown by the high values for bulk density between the rows of the sugarcane cultivars.

DIRECT INFUSION ESI-MS APPLIED IN THE DETECTION OF BYPRODUCTS DUE TO REDUCTIVE DEGRADATION OF ACETAMIPRID BY ZERO-VALENT IRON

This study investigated the reductive degradation of acetamiprid (5 mg L-1) in aqueous medium (at pH 2.0) induced by zero-valent iron (50 mg). The process was monitored using high-performance liquid chromatography (HPLC) to determine the degradation rate as a function of reaction time, and direct infusion electrospray ionization mass spectrometry (DI-ESI-MS) to search for (and potentially characterize) any possible byproducts formed during degradation. The results obtained via HPLC showed that after 60 min, the degradation of the substrate reached nearly 100% in an acidic medium, whereas the mineralization rate (as determined by total organic carbon measurements) was as low as 3%. Data obtained by DI-ESI-MS showed that byproducts were formed mainly by insertions of hydrogen atoms into the nitrile, imine, and pyridine ring moieties, in addition to the observation of chlorine substitution by hydrogen replacement (hydrodechlorination) reactions.

Chinese multinational corporations in Brazil: strategies and implications in energy and telecom sectors

This study aims to understand how Chinese enterprises acted in Brazilian energy and telecommunication sectors in the past ten years and whether they would be leading to an increase in the asymmetries between Brazil and China. It argues that the asymmetries presented in the relations are due in large part to successful Chinese enterprises' strategies.

Chinese energy policy progress and challenges in the transition to low carbon development, 2006-2013

If the world is not to jeopardize the chances for human life on Earth, climate change must be mitigated; therefore, achieving low carbon development is crucial. China is the world's greatest GHG emitter, energy producer and energy consumer; investigating its energy-climate policy developments and international positions are of utmost importance to understand and tackle current stumbling blocks of the global energy and climate governance.

Public hearings as a tool to improve participation in regulatory policies: case study of the National Agency of Electric Energy

The participation of citizens in public policies is an opportunity not only to educate them, but also to increase their empowerment. However, the best way for deploying participatory policies, defining their scope and approach, still remains an open and continuous debate. Using as a case study the Brazilian National Agency of Electric Energy (Aneel), with its public hearings about tariff review, this paper aims at analyzing the democratic aspects of these hearings and challenges the hypothesis of many scholars about the social participation bias in this kind of procedure. This study points out a majority participation of experts, contrasting with the political content of discussions. And, this way, it contributes to a critical analysis of the public hearings as a participatory tool, indicating their strengths and their aspects which deserve a special attention.

Imunidade relativa à poliomielite em crianças de zero a dez anos, após o "Quarto Dia Nacional de Vacinação Contra a Poliomielite" com a vacinação oral trivalente, tipo Sabin, em área da Região da Grande São Paulo, SP (Brasil), 1982

Efetuou-se um levantamento soro-epidemiológico, abrangendo 898 crianças, para a verificação da imunidade aos poliovírus 1, 2 e 3 por meio da determinação dos títulos de anticorpos neutralizantes. De 522 crianças, ou seja, de 58,1% da população estudada, foi possível a obtenção de informações referentes à situação vacinal a partir de anotações existentes nas próprias Cadernetas de Vacinação. Neste último sub-grupo foi estudado o estado imunitário em relação ao número de doses de vacina oral tipo Sabin recebidas. Os resultados mostraram alta proporção de imunes para os três tipos de poliovírus entre as crianças estudadas, porém também revelaram a existência de lacuna imunitária nos menores de um ano, especialmente no primeiro semestre de vida. Não foram observadas diferenças importantes na proporção de imunes segundo o sorotipo considerado. Salientou-se a necessidade de um alerta constante e permanente em relação à ocorrência de possíveis surtos epidêmicos em segmentos mais vulneráveis da população, particularmente entre crianças menores de 1 ano.

Diagnóstico nutricional de crianças de zero a cinco anos atendidas pela rede municipal de saúde em área urbana da região sul do Brasil, 1988

Como um dos requisitos para a operacionalização do Sistema de Vigilância Alimentar e Nutricional (SISVAN) no município de Curitiba, PR, Brasil, foi realizado um levantamento epidemiológico retrospectivo com dados de 1988, que buscou através do exame antropométrico conhecer a prevalência e as formas de desnutrição calórico-protéico de crianças menores de cinco anos atendidas pela Rede Municipal de Saúde de Curitiba. Numa amostra de 4.213 crianças encontrou-se pela Classificação de Gòmez 28,1% de desnutridos, sendo que 3,6% destes situam-se no grau II e III. A Classificação de Seoane e Latham modificada por Batista Filho revelou que 19,7% das crianças apresentam alguma forma de desnutrição. O perfil antropométrico revelou maior concentração de crianças no primeiro decil a partir do sexto mês de vida, sendo esta mais acentuada no grupo etário de 12 a 24 meses para os índices: peso/idade e altura/idade.