Evanescent-wave trapping and evaporative cooling of an atomic gas near two-dimensionality

A dense gas of cesium atoms at the crossover to two-dimensionality is prepared in a highly anisotropic surface trap that is realized with two evanescent light waves. Temperatures as low as 100nK are reached with 20.000 atoms at a phase-space density close to 0.1. The lowest quantum state in the tightly confined direction is populated by more than 60%. The system offers intriguing prospects for future experiments on degenerate quantum gases in two dimensions

Evaluating the Application of Microbial Induced Calcite Precipitation Technique to Stabilize Expansive Soils

Expansive soils, also known as swell-shrink soils have been a problem for civil infrastructures including roads and foundations from ancient times. The use of chemical additives such as cement and lime to stabilize expansive soils is a common practice among geotechnical engineers, especially for lightly loaded structures. However, several occurrences of subgrade failures have been observed after stabilizing with chemical additives. Hence, engineers are in search of sustainable stabilization alternatives. Microbial Induced Calcite Precipitation (MICP) is gaining attention as an environmentally friendly soil improvement technique. Several researchers have successfully tested its feasibility in mitigating liquefaction-induced problems in sandy soils. In this research, the authors are evaluating its effectiveness in stabilizing expansive soils. For this purpose two natural expansive soils with high and low plasticity properties were subjected to MICP treatments. The soil samples were first augmented with bacterium Sporosarcina Pasteurii and then treated with Calcium Chloride and Urea. Variables such as microbial concentrations and curing times were studied in this research. Geotechnical testing including Atterberg limits and unconfined compression strength were performed to evaluate the efficacy of MICP treatments. Preliminary results indicate that there is a reduction in plasticity and swelling characteristics of the soils and increase in the unconfined compression strength

Cerebrovascular dysfunction and microcirculation rarefaction precede white matter lesions in a mouse genetic model of cerebral ischemic small vessel disease

Cerebral ischemic small vessel disease (SVD) is the leading cause of vascular dementia and a major contributor to stroke in humans. Dominant mutations in NOTCH3 cause cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a genetic archetype of cerebral ischemic SVD. Progress toward understanding the pathogenesis of this disease and developing effective therapies has been hampered by the lack of a good animal model. Here, we report the development of a mouse model for CADASIL via the introduction of a CADASIL-causing Notch3 point mutation into a large P1-derived artificial chromosome (PAC). In vivo expression of the mutated PAC transgene in the mouse reproduced the endogenous Notch3 expression pattern and main pathological features of CADASIL, including Notch3 extracellular domain aggregates and granular osmiophilic material (GOM) deposits in brain vessels, progressive white matter damage, and reduced cerebral blood flow. Mutant mice displayed attenuated myogenic responses and reduced caliber of brain arteries as well as impaired cerebrovascular autoregulation and functional hyperemia. Further, we identified a substantial reduction of white matter capillary density. These neuropathological changes occurred in the absence of either histologically detectable alterations in cerebral artery structure or blood-brain barrier breakdown. These studies provide in vivo evidence for cerebrovascular dysfunction and microcirculatory failure as key contributors to hypoperfusion and white matter damage in this genetic model of ischemic SVD

Proposta corporativa para implantação de gestão ambiental na Embrapa.

Este documento traduz uma iniciativa que contribui para a internalização de conceitos e orientações visando à implantação de instrumentos de gestão ambiental na Embrapa, em consonância com a explícita preocupação da empresa quanto à sua atuação institucional de vanguarda em termos de adoção de responsabilidade e ética para o desenvolvimento sustentável. Para gerir as atividades do projeto, foi criado um comitê gestor formado por representantes de várias unidades, e da própria sede, com perfil multidisciplinar. Este comitê focou sua atenção na realização de um diagnóstico sobre o estágio de disseminação da cultura da questão ambiental no corpo técnico e administrativo das unidades descentralizadas da Embrapa. Dessa forma, foi possível evidenciar as diferenças existentes nos diversos centros de pesquisa bem como as dificuldades para a implantação de um sistema de gestão ambiental, em função da diversidade geográfica da localização de algumas unidades, da cultura local, da percepção ambiental e importância dada à questão ambiental em certas unidades, da qualificação dos recursos humanos para lidar com o tema meio ambiente e , outras vezes, da inadequação das instalações prediais de várias unidades. Como resultado desse esforço, foi construído um modelo de gestão ambiental para a Embrapa, fundamentado em experiências bem sucedidas de algumas unidades e validado pelo corpo técnico da própria empresa. Este modelo deu início à incorporação das questões ambientais na cultura organizacional, por meio dos planos de ação do projeto que originou este documento (Projeto de Gestão Ambiental: uma proposta corporativa da Embrapa), e que abrigavam procedimentos relativos à educação ambiental corporativa, gestão de resíduos laboratoriais, gestão de campos experimentais, gestão integrada de resíduos, gestão de áreas protegidas e realização de plano de manejo para as unidades da Embrapa.bitstream/item/108222/1/2009-DOC-0097.pd