DNA-psoralen: single-molecule experiments and first principles calculations

The authors measure the persistence and contour lengths of DNA-psoralen complexes, as a function of psoralen concentration, for intercalated and crosslinked complexes. In both cases, the persistence length monotonically increases until a certain critical concentration is reached, above which it abruptly decreases and remains approximately constant. The contour length of the complexes exhibits no such discontinuous behavior. By fitting the relative increase of the contour length to the neighbor exclusion model, we obtain the exclusion number and the intrinsic intercalating constant of the psoralen-DNA interaction. Ab initio calculations are employed in order to provide an atomistic picture of these experimental findings.Comment: 9 pages, 4 figures in re-print format 3 pages, 4 figures in the published versio

Modified Beer-Lambert law for blood flow

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPWe develop and validate a Modified Beer-Lambert law for blood flow based on diffuse correlation spectroscopy (DCS) measurements. The new formulation enables blood flow monitoring from temporal intensity autocorrelation function data taken at single or multiple delay-times. Consequentially, the speed of the optical blood flow measurement can be substantially increased. The scheme facilitates blood flow monitoring of highly scattering tissues in geometries wherein light propagation is diffusive or non-diffusive, and it is particularly well-suited for utilization with pressure measurement paradigms that employ differential flow signals to reduce contributions of superficial tissues.51140534075FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2012/02500-82013/07559-3We gratefully acknowledge help from Marion Knaus and Victoria Pallett per preparing the pig, and we thank longtime collaborators Daniel Licht, John Detre, Emile Mohler, Thomas Floyd, Turgut Durduran, and Theresa Busch for valuable discussions. We acknowledge support from the National Institutes of Health (R01-NS060653, NHLBI-HL007915, 8P41-EB015893), the American Heart Association (ABP, 14POST20460161), the Thrasher Pediatric Research Foundation Early Career Award (DRB), and the Sao Paulo Research Foundation (RCM, 2012/02500-8, 2013/07559-3)

Modified Beer-Lambert law for blood flow

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOThe modified Beer-Lambert law is among the most widely used approaches for analysis of near-infrared spectroscopy (NIRS) reflectance signals for measurements of tissue blood volume and oxygenation. Briefly, the modified Beer-Lambert paradigm is a scheme to derive changes in tissue optical properties based on continuous-wave (CW) diffuse optical intensity measurements. In its simplest form, the scheme relates differential changes in light transmission (in any geometry) to differential changes in tissue absorption. Here we extend this paradigm to the measurement of tissue blood flow by diffuse correlation spectroscopy (DCS). In the new approach, differential changes of the intensity temporal auto-correlation function at a single delay-time are related to differential changes in blood flow. The key theoretical results for measurement of blood flow changes in any tissue geometry are derived, and we demonstrate the new method to monitor cerebral blood flow in a pig under conditions wherein the semi-infinite geometry approximation is fairly good. Specifically, the drug dinitrophenol was injected in the pig to induce a gradual 200% increase in cerebral blood flow, as measured with MRI velocity flow mapping and by DCS. The modified Beer-Lambert law for flow accurately recovered these flow changes using only a single delay-time in the intensity auto-correlation function curve. The scheme offers increased DCS measurement speed of blood flow. Further, the same techniques using the modified Beer-Lambert law to filter out superficial tissue effects in NIRS measurements of deep tissues can be applied to the DCS modified Beer-Lambert law for blood flow monitoring of deep tissues.The modified Beer-Lambert law is among the most widely used approaches for analysis of near-infrared spectroscopy (NIRS) reflectance signals for measurements of tissue blood volume and oxygenation. Briefly, the modified Beer-Lambert paradigm is a scheme to derive changes in tissue optical properties based on continuous-wave (CW) diffuse optical intensity measurements. In its simplest form, the scheme relates differential changes in light transmission (in any geometry) to differential changes in tissue absorption. Here we extend this paradigm to the measurement of tissue blood flow by diffuse correlation spectroscopy (DCS). In the new approach, differential changes of the intensity temporal auto-correlation function at a single delay-time are related to differential changes in blood flow. The key theoretical results for measurement of blood flow changes in any tissue geometry are derived, and we demonstrate the new method to monitor cerebral blood flow in a pig under conditions wherein the semi-infinite geometry approximation is fairly good. Specifically, the drug dinitrophenol was injected in the pig to induce a gradual 200% increase in cerebral blood flow, as measured with MRI velocity flow mapping and by DCS. The modified Beer-Lambert law for flow accurately recovered these flow changes using only a single delay-time in the intensity auto-correlation function curve. The scheme offers increased DCS measurement speed of blood flow. Further, the same techniques using the modified Beer-Lambert law to filter out superficial tissue effects in NIRS measurements of deep tissues can be applied to the DCS modified Beer-Lambert law for blood flow monitoring of deep tissues.9319123FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO2012/02500-8; 2013/07559-311. Conference on Optical Tomography and Spectroscopy of Tissue9 a 11 de Fevereiro de 2015San Francisco, CASPIE - International Society for Optical EngineeringAgências de fomento estrangeiras apoiaram essa pesquisa, mais informações acesse artig

Crescimento de mudas de dendezeiro produzidas em tubetes plásticos durante o previveiro em função da aplicação de doses crescentes de Osmocote®.

Atualmente, a utilização de tubetes plásticos durante a fase de previveiro na formação de mudas de dendezeiro (Elaeis guineensis Jacq.) tem sido estudada, apresentando-se como boa alternativa ao sistema de produção tradicional de mudas, mas esta metodologia ainda carece de aperfeiçoamento. Este trabalho teve como objetivos verificar o efeito da adição de doses crescentes de Osmocote®, durante a fase de previveiro, no crescimento e na partição de matéria seca de mudas de dendezeiro produzidas em tubetes plásticos

DRIS standards for nutritional evaluation of Phaseolus vulgaris in Cerrado, Goiás State, Brazil.

The knowledge of nutritional requirements of beans, the efficiency of soil acidity correction and the fertilization programs are essential to increase productivity. The Integrated Recommendation and Diagnosis System (DRIS) assists with nutritional diagnosis of cultivated plants based on existing interactions between nutrients and the hierarchizing of limitations. This study aimed at establishing standards using the DRIS method for areas of production of irrigated common beans and at determining the most limiting nutritional factors to production using leaf analyses interpreted by concentration ranges and DRIS. Eighteen different beanproducing areas were selected in a central pivot irrigation system, from which 82 sampling points were established to collect leaves of crop and determine their nutritional contents. The reference population had productivity of over 3,000 kg ha- 1. Using DRIS, we determined that phosphorus is the most limiting nutrient regarding its deficiency, with great sensitivity to diagnose nutritional problems of plants, especially micronutrients. Phosphorus (68.3%), molybdenum (65.9%), iron (64.6 %) and sodium (63.4%) and are nutrients with highest percentage of samples presenting levels below adequate according to sufficiency ranges for plants. Using DRIS, we can evaluate interactions among nutrients and determine of the magnitude of crop nutritional limitation whether due to deficiency or excess. These results may indicate which nutrients are limiting the crop productive capacity, allowing greater efficiency in its correction in soil

Caracterização de híbridos de melão do grupo inodorus desenvolvidos pela Embrapa Agroindústria Tropical.

bitstream/CNPAT-2010/11918/1/bd-26.pd

Bias in protein and potassium intake collected with 24-h recalls (EPIC-Soft) is rather comparable across European populations

Purpose: We investigated whether group-level bias of a 24-h recall estimate of protein and potassium intake, as compared to biomarkers, varied across European centers and whether this was influenced by characteristics of individuals or centers. Methods: The combined data from EFCOVAL and EPIC studies included 14 centers from 9 countries (n = 1,841). Dietary data were collected using a computerized 24-h recall (EPIC-Soft). Nitrogen and potassium in 24-h urine collections were used as reference method. Multilevel linear regression analysis was performed, including individual-level (e.g., BMI) and center-level (e.g., food pattern index) variables. Results: For protein intake, no between-center variation in bias was observed in men while it was 5.7% in women. For potassium intake, the between-center variation in bias was 8.9% in men and null in women. BMI was an important factor influencing the biases across centers (p <0.01 in all analyses). In addition, mode of administration (p = 0.06 in women) and day of the week (p = 0.03 in men and p = 0.06 in women) may have influenced the bias in protein intake across centers. After inclusion of these individual variables, between-center variation in bias in protein intake disappeared for women, whereas for potassium, it increased slightly in men (to 9.5%). Center-level variables did not influence the results. Conclusion: The results suggest that group-level bias in protein and potassium (for women) collected with 24-h recalls does not vary across centers and to a certain extent varies for potassium in men. BMI and study design aspects, rather than center-level characteristics, affected the biases across center

Capacitar profissionais para trabalhar/difundir a segurança alimentar e nutricional da comunidade

Trabalho apresentado no II Congresso Nacional do PROJETO RONDON, realizado em Florianópolis, SC, no período de 23 a 25 de setembro de 2015 - Universidade Federal de Santa Catarina.O conceito de Segurança alimentar e Nutricional (SAN) é muito amplo, define-se como o direito de todos ao acesso a alimentos de qualidade e em quantidade, sem comprometer o acesso a outras necessidades essenciais. Além disso, a SAN constitui a prática de uma alimentação adequada com alimentos saudáveis, e consumir nutrientes necessários para as atividades diárias de cada cidadão. Sendo assim, foi desenvolvida durante a Operação Bororos - julho/2015, no Conjunto A de atividades no município de Nortelândia/MT, uma oficina que objetivou o esclarecimento dos direitos supracitados a toda população, além de promover o conhecimento sobre os alimentos que estão disponíveis para o consumo, e quais os benefícios que estes podem trazer para a saúde, sua quantidade e variedade adequada. Além de direcionar formas de promoção à alimentação saudável e de auto produção e consumo. Esta oficina foi desenvolvida na Escola Municipal Júlio Praxe de Duarte com auxílio de recursos audiovisuais para 47 pessoas que incluíam profissionais da área da saúde, merendeiras e comunidade em geral. Foram dois dias de atividade no período integral (manhã e tarde), onde no primeiro dia foram desenvolvidas atividades teóricas sobre conceitos de SAN, componentes dos alimentos, grupos alimentares, e aspectos de higiene alimentar. No segundo dia foram desenvolvidas atividades práticas, sendo construída, no período matutino uma horta comunitária no pátio da escola e no período vespertino praticado o monitoramento da SAN para a população, como exemplo, a realização do cálculo do Índice de Massa Corporal (IMC). Foi verificado que houve impacto das informações sobre a população, que se sentiu esclarecida, sendo ouvidos muitos relatos que deixou exposto que o ato de alimentar-se não expressava tanta preocupação com relação a qualidade e propósito dos alimentos. Também constatou-se que o conhecimento sobre como alimentar-se, e o que ingerir, e o porquê consumir tais alimentos apresentaram conceitos novos. Conclui-se desta forma que a atividade promoveu um impacto sobre a comunidade implicando em sua qualidade de vida, e que poderá ser replicada mesmo após a conclusão do trabalho dos rondonistas