Haciendo hologramas en la escuela y en la casa

La comunidad científica que se ocupa de los problemas relacionados con el proceso de enseñanza-aprendizaje de la físicas, ha dedicado muchos esfuerzos en los ultimos años al perfeccionamiento del mismo, motivado en primera instancia, por las demandas de renovación que el impetuoso desarrollo científico-técnico le impone en la actualidad a la enseñanza de las ciencias. En los últimos años se ha producido un desarrollo vertiginoso en la fabricación de diodos láser que emiten en el espectro visible, esto ha permitido su utilización creciente en múltiples aplicaciones y hace factible su utilización en la enseñanza aprendizaje de la física universitaria y en particular de la holografía, por sus grandes ventajas frente a los láseres convencionales de gran costo y difícil manipulación. En el trabajo se describen la instalación experimental portátil diseñada para la obtención de hologramas en la escuela y en la casa con la utilización de diodos láser, la metodología de trabajo a seguir, los métodos de procesamiento utilizados para diferentes tipos de emulsiones holográficas y un análisis de los defectos que pueden presentar los hologramas producidos y la forma de detectarlos y erradicarlos

Biogeochemical processes and the diversity of Nhecolândia lakes, Brazil

The Pantanal of Nhecolândia, the world's largest and most diversified field of tropical lakes, comprises approximately 10,000 lakes, which cover an area of 24,000 km² and vary greatly in salinity, pH, alkalinity, colour, physiography and biological activity. The hyposaline lakes have variable pHs, low alkalinity, macrophytes and low phytoplankton densities. The saline lakes have pHs above 9 or 10, high alkalinity, a high density of phytoplankton and sand beaches. The cause of the diversity of these lakes has been an open question, which we have addressed in our research. Here we propose a hybrid process, both geochemical and biological, as the main cause, including (1) a climate with an important water deficit and poverty in Ca2+ in both superficial and phreatic waters; and (2) an elevation of pH during cyanobacteria blooms. These two aspects destabilise the general tendency of Earth's surface waters towards a neutral pH. This imbalance results in an increase in the pH and dissolution of previously precipitated amorphous silica and quartzose sand. During extreme droughts, amorphous silica precipitates in the inter-granular spaces of the lake bottom sediment, increasing the isolation of the lake from the phreatic level. This paper discusses this biogeochemical problem in the light of physicochemical, chemical, altimetric and phytoplankton data.

ScriptLattes: an open-source knowledge extraction system from the Lattes platform

The Lattes platform is the major scientific information system maintained by the National Council for Scientific and Technological Development (CNPq). This platform allows to manage the curricular information of researchers and institutions working in Brazil based on the so called Lattes Curriculum. However, the public information is individually available for each researcher, not providing the automatic creation of reports of several scientific productions for research groups. It is thus difficult to extract and to summarize useful knowledge for medium to large size groups of researchers. This paper describes the design, implementation and experiences with scriptLattes: an open-source system to create academic reports of groups based on curricula of the Lattes Database. The scriptLattes system is composed by the following modules: (a) data selection, (b) data preprocessing, (c) redundancy treatment, (d) collaboration graph generation among group members, (e) research map generation based on geographical information, and (f) automatic report creation of bibliographical, technical and artistic production, and academic supervisions. The system has been extensively tested for a large variety of research groups of Brazilian institutions, and the generated reports have shown an alternative to easily extract knowledge from data in the context of Lattes platform. The source code, usage instructions and examples are available at http://scriptlattes.sourceforge.net/.

T.W. Adorno e a psicologia social

Neste ensaio, ressalta-se a importância da disciplina Psicologia Social na obra de T. W. Adorno e a concepção que formula acerca dessa disciplina. Esse autor defende que há uma nova forma de configuração dos indivíduos, expressada por atitudes e comportamentos individuais padronizados e por um ego frágil, facilmente cooptado por movimentos sociais totalitários. Tais indivíduos surgem em uma sociedade caracterizada por uma forma de dominação calcada na racionalidade administrativa e tecnológica. Para esse autor, a Psicologia Social deveria estudar esse objeto para que, com o esclarecimento produzido e difundido, os indivíduos possam resistir à adesão cega a movimentos sociais irracionais, tal como o fascismo, insistindo que a determinação desses movimentos não é individual, mas social.

Relações entre preconceito, ideologia e atitudes frente à educação inclusiva

Este artigo analisa atitudes de alunos de um curso de pedagogia frente à educação inclusiva. Parte da hipótese de que o preconceito e a ideologia podem ser obstáculos à inclusão de crianças com deficiência na escola. Foram aplicadas quatro escalas: Manifestação de Preconceito, Atitudes Frente à Educação Inclusiva e Ideologia da Racionalidade Tecnológica, elaboradas por Crochík em 2000, 2003 e 2006, e a escala F, construída por Adorno, Frenkel-Brunswik, Levinson e Sanford em 1950. O estudo foi realizado com 188 estudantes de pedagogia. Os alunos desta amostra tenderam a ser mais favoráveis do que desfavoráveis à educação inclusiva, e foi possível verificar que o preconceito, a adesão à ideologia da racionalidade tecnológica e, implicitamente, ao fascismo, são variáveis que se relacionam às atitudes acerca desse tipo de educação.

Solvation simplified

The effects of solvents on chemical phenomena is complex because there are various solute-solvent interaction mechanisms. Solvatochromism refers to the effects of solvents on the spectra of probes. The study of this phenomenon sheds light on the relative importance of the solvation mechanisms. Solvation in pure solvents is quantitatively analyzed in terms of a multi-parameter equation. In binary solvent mixtures, solvation is analyzed by considering the organic solvent, S, water, W, and a 1:1 hydrogen bonded species (S-W). The applications of solvatochromism to understand distinct chemical phenomena, reactivity and swelling of cellulose, is briefly discussed.

Análise direta de sólidos por espectrometria de absorção atômica com atomização em forno de grafite: uma revisão

This is a review of direct analysis using solid sampling graphite furnace atomic absorption spectrometry. Greater emphasis is dedicated to sample preparation, sample homogeneity, calibration and its application to microanalysis and micro-homogeneity studies. The main advantages and some difficulties related to the applicability of this technique are discussed. A literature search on the application of solid sampling graphite furnace atomic absorption spectrometry in trace element determination in many kinds of samples, including biological, clinical, technological and environmental ones, is also presented.

Benthic macrofauna structure in the northeast area of Todos os Santos Bay, Bahia State, Brazil: patterns of spatial and seasonal distribution

Structure of intertidal and subtidal benthic macrofauna in the northeastern region of Todos os Santos Bay (TSB), northeast Brazil, was investigated during a period of two years. Relationships with environmental parameters were studied through uni-and multivariate statistical analyses, and the main distributional patterns shown to be especially related to sediment type and content of organic fractions (Carbon, Nitrogen, Phosphorus), on both temporal and spatial scales. Polychaete annelids accounted for more than 70% of the total fauna and showed low densities, species richness and diversity, except for the area situated on the reef banks. These banks constitute a peculiar environment in relation to the rest of the region by having coarse sediments poor in organic matter and rich in biodetritic carbonates besides an abundant and diverse fauna. The intertidal region and the shallower area nearer to the oil refinery RLAM, with sediments composed mainly of fine sand, seem to constitute an unstable system with few highly dominant species, such as Armandia polyophthalma and Laeonereis acuta. In the other regions of TSB, where muddy bottoms predominated, densities and diversity were low, especially in the stations near the refinery. Here the lowest values of the biological indicators occurred together with the highest organic compound content. In addition, the nearest sites (stations 4 and 7) were sometimes azoic. The adjacent Caboto, considered as a control area at first, presented low density but intermediate values of species diversity, which indicates a less disturbed environment in relation to the pelitic infralittoral in front of the refinery. The results of the ordination analyses evidenced five homogeneous groups of stations (intertidal; reef banks; pelitic infralittoral; mixed sediments; Caboto) with different specific patterns, a fact which seems to be mainly related to granulometry and chemical sediment characteristics.

Phlebotomines (Diptera, Psychodidae) in the Ribeira Valley Speleological Province - 1. Parque Estadual Intervales, state of São Paulo, Brazil

The identification of the sandfly fauna and investigation of some ecological aspects of its populations in areas frequented by tourists of the PEI, an Atlantic forest reserve with many caves, were the objective of this study. Captures were undertaken monthly from January 2001 to December 2002, with automatic light traps installed in 13 ecotopes, including caves, forests, domiciliary and peridomiciliary environments, and by aspiration in armadillo burrows. Additionally, although not at regular intervals, Shannon traps were installed in forests and anthropic environments, aspirations were made on cave walls, among roots and fallen leaves, and some insects were captured while biting researchers. A total of 891 sandflies belonging to 21 species were captured. Six hundred specimens representing 19 species were captured with light traps, 215 in anthropic (2.24 insects/trap) and 385 in extra-domiciliary (1.46 insects/trap) environments. Brumptomyia troglodytes was the most abundant species (the Standardised Index of Species Abundance = 0.705). Pintomyia monticola predominated in the Shannon traps and showed anthropophilic and diurnal activity. Psathyromyia pascalei predominated in the aspirations; the largest number being in armadillo burrows. Eleven species were captured in caves; although some might be troglophiles, the majority used these ecotopes as resting places. Nyssomyia intermedia, Nyssomyia neivai and Migonemyia migonei, implicated in the transmission of cutaneous leishmaniasis in the Southeastern Brazilian region, were all found, though in such low densities as to suggest minimal risk of the disease in the PEI.

Habitat suitability of Anopheles vector species and association with human malaria in the Atlantic Forest in south-eastern Brazil

Every year, autochthonous cases of Plasmodium vivax malaria occur in low-endemicity areas of Vale do Ribeira in the south-eastern part of the Atlantic Forest, state of São Paulo, where Anopheles cruzii and Anopheles bellator are considered the primary vectors. However, other species in the subgenus Nyssorhynchus of Anopheles (e.g., Anopheles marajoara) are abundant and may participate in the dynamics of malarial transmission in that region. The objectives of the present study were to assess the spatial distribution of An. cruzii, An. bellator and An. marajoara and to associate the presence of these species with malaria cases in the municipalities of the Vale do Ribeira. Potential habitat suitability modelling was applied to determine both the spatial distribution of An. cruzii, An. bellator and An. marajoara and to establish the density of each species. Poisson regression was utilized to associate malaria cases with estimated vector densities. As a result, An. cruzii was correlated with the forested slopes of the Serra do Mar, An. bellator with the coastal plain and An. marajoara with the deforested areas. Moreover, both An. marajoara and An. cruzii were positively associated with malaria cases. Considering that An. marajoara was demonstrated to be a primary vector of human Plasmodium in the rural areas of the state of Amapá, more attention should be given to the species in the deforested areas of the Atlantic Forest, where it might be a secondary vector.

Time trends and predictors of mortality from ill-defined causes in old age: 9 year folllow-up of the Bambuí cohort study (Brazil)

The study objective was to examine differentials in time trends and predictors of deaths assigned to symptoms, signs and ill-defined conditions in comparison with other ill-defined conditions (ill-defined cardiovascular diseases, cancer and injury) in a population-based cohort study. Of 1,606 baseline participants aged 60 years and over, 524 died during 9-year follow-up and were included in this study. Deaths coded to "symptoms" declined by 77% in the period from 1997-1999 to 2003-2005. Deaths coded to other ill-defined conditions remained unchanged. The calendar period 2003-2005 (RR = 0.25; 95%CI: 0.09-0.70) and in-hospital deaths (RR = 0.16; 95%CI: 0.08-0.34) were independently associated with "symptoms", but not with other ill-defined conditions. Baseline socio-demographic characteristics and chronic diseases were not predictors of these outcomes. International and national agencies have focused on the reduction of deaths assigned to "symptoms" to improve the registration of vital statistics, while other ill-defined conditions have received little attention. Our data provide evidence supporting the need to redress this situation.

Competição entre larvas de Aedes aegypti e Aedes albopictus em laboratório

Este estudo teve como objetivo avaliar os efeitos da competição larval intra e interespecífica entre Aedes aegypti e Aedes albopictus, sobre sobrevivência de larvas, tempo de desenvolvimento e comprimento de asa. O experimento foi realizado em três densidades com 5 proporções das espécies. A sobrevivência de Aedes aegypti apresentou-se superior a de Aedes albopictus em densidade intermediária e inferior em densidade alta. Somente Aedes albopictus teve seu tempo de desenvolvimento afetado. Diferenças encontradas nas comparações das combinações das espécies demonstraram que o comprimento médio de asas de Aedes aegypti, no geral, foi maior que Aedes albopictus. Nas duas espécies, a competição afetou mais o comprimento de asa e a sobrevivência que o tempo de desenvolvimento. Aedes aegypti parece apresentar maior capacidade competitiva em relação a Aedes albopictus em densidade intermediária.

Color/race inequalities in oral health among Brazilian adolescents

This study assessed oral health outcomes (perceived dental treatment need, untreated dental caries, gingival bleeding, periodontal pockets, and pain in teeth and gums), in relation to color/race inequalities among adolescents in each Brazilian region. The database included dental examination and interview of 16,833 15-19-year-old adolescents, surveyed by the Brazilian health authority, from May 2002 to October 2003, in accordance with international diagnostic criteria standardized by the World Health Organization. Prevalence ratios estimated by Poisson regression, and controlled by socioeconomic status and access to fluoridated piped water, assessed oral health differentials among color/race groups and country's regions. Except for periodontal pockets, prevalence figures were higher in the North and Northeast: perceived dental treatment needs, untreated dental caries, gingival bleeding at probing and pain in teeth and gums varied between 80-83%, 75-76%, 38-43%, and 17-18%, respectively, in these regions. Adolescents living in the Southeast - the richest Brazilian region - presented a better general profile of oral health than their counterparts living in the remaining regions; they had a lower prevalence of untreated dental caries (54%) and unfavorable gingival status (29%). However, the Southeast presented color/race inequalities in all oral health outcomes, with a poorer profile systematically affecting browns or blacks, depending on the oral health condition under consideration. These results reinforce the need for expanding the amplitude of health initiatives aimed at adolescent oral health. Socially appropriate health programs should concurrently aim at the reduction of levels of oral disease and its inequalities.

Body trunk fat and insulin resistance in post-pubertal obese adolescents

CONTEXT AND OBJECTIVE: Insulin resistance is a metabolic disorder commonly associated with excess body fat accumulation that may increase chronic disease risk. The present study was undertaken to evaluate the relationship between body composition and insulin resistance among obese adolescents. DESIGN AND SETTING: Cross-sectional study, at the Adolescence Center, Pediatric Department, Universidade Federal de São Paulo. METHODS: Body composition was assessed using dual-energy X-ray absorptiometry. Dietary intake was evaluated using a three-day dietary record. The biochemical evaluation comprised glucose, insulin, serum lipid, leptin and ghrelin measurements. Insulin resistance was calculated by means of the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Forty-nine post-pubertal obese adolescents participated in the study: 12 boys and 37 girls of mean age 16.6 (1.4) years and mean body mass index (BMI) of 35.0 (3.9) kg/m². The mean glucose, insulin and HOMA values were 90.3 (6.4) mg/dl, 16.6 (8.1) µIU/ml and 3.7 (1.9), respectively. Hyperinsulinemia and insulin resistance were observed in 40.2% and 57.1% of the subjects, respectively. Adolescents with insulin resistance had higher BMI and body trunk fat. There was a trend towards higher leptin concentration in obese individuals with insulin resistance. Insulin resistance was positively correlated with body trunk fat, BMI, body fat mass (kg), leptin and body fat percentage. Furthermore, there was a negative correlation between HOMA-IR and lean body mass. The body composition predicted 30% of the HOMA-IR levels, according to linear regression models. CONCLUSION: Body trunk fat was significantly associated with insulin resistance, demonstrating the clinical importance of abdominal obesity during adolescence.

Novas perspectivas na gestão do sistema de saúde da Espanha

Ao longo dos últimos vinte e cinco anos, a organização do sistema de saúde na Espanha vem adotando diversas medidas que reorientaram seu gerenciamento, melhoraram sua eficiência e aprimoraram seu sistema de financiamento, resultado de profundas reformas e da introdução de novos instrumentos de gestão. Este artigo é resultado de uma análise documental que objetivou descrever a trajetória de conformação do sistema de saúde espanhol e sua organização na contemporaneidade. Apresenta alguns determinantes históricos que tornaram possíveis as reformas no setor sanitário, como a descentralização para o nível das Comunidades Autônomas, a incorporação de mecanismos de coordenação e a integração e o financiamento dos novos e distintos formatos organizativos coexistentes no país. Além disso, identifica desafios que emergem no cenário atual do Sistema Nacional de Saúde, como o fenômeno da imigração, o avançado processo de transição demográfica, a crescente demanda por melhorias na qualidade da atenção e de incorporação tecnológica. Todos esses fatores influem na sustentabilidade do sistema, o que motivou a criação de mais um espaço para estabelecimentos de consensos sobre o papel fundamental do sistema sanitário para o Estado de Bem-Estar espanhol.