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This paper aims to introduce the initiative "Escola Sirius para Professores do Ensino Médio" (ESPEM, Sirius School for High School Teachers) hosted by the "Centro Nacional de Pesquisa em Energia e Materiais" (CNPEM, Brazilian Center for Research in Energy and Materials) and supported by the Sociedade Brasileira de Física (SBF, Brazilian Physical Society). The program covers the principles and applications of synchrotron radiation with expositive lectures, discussions, and visits to the CNPEM facilities. By using semi structured interviews, a remote focal group and surveys to find out the impact of ESPEM, we observed that the teachers shared their experience and disseminate the acquired knowledge with their peers and students.

The role of peer and teacher mediation in discussions about two original scientific texts in the final year of high school in Brazil is explored in this study. A text by James C. Maxwell, deals with the characterisation of light as an electromagnetic phenomenon, and refers to the continuous manner of the distribution of energy by radiation in space. The other, by Ludwig Boltzmann, is about thermodynamics in its probabilistic conception and some of its consequences for the comprehension of the nature of heat. We analyse some of the students' interpretations using a version of discourse analysis, developed in Brazil following the French tradition of Michel Pêcheux. We highlight interactions that contribute to the reading of the texts and the mediations of both the teacher and peers that promote the establishment of relevant meanings about physics concepts. The appropriation of their statements about the content is observed in this communicative approach. We contribute to the investigation of physics teaching using strategies informed by a humane scientific and cultural educational perspective in high schools.

This research aimed to investigate the misconceptions on nuclear physics topics. Misconceptions are defined as ideas whose meaning departs from what is commonly accepted by scientific consensus. A total of 34 high school students of the Federal Institute of Education, Science and Technology of Sao Paulo (IFSP), Brazil, answered a questionnaire on atomic model, radiation and radioactivity themes. The results showed that more than half of the students used similar representations to the Rutherford model when they had to draw an atom. In addition, at least 60% of the students had heard about radiation but could not explain the scientific meaning of the term. Also, it was noted in the research the influence of knowledge acquired by students outside the classroom by mentions made on nuclear fission, a topic not covered in the curriculum, and the frequent use of the Rutherford atomic model, ideas often conveyed by the media. Thus, there is a need for further discussion by teachers and teachers in training on the inclusion of nuclear physics topics in the high school curriculum.

Harmful plastic debris found on beaches and in the oceans are not limited to drinking straws or bags. There are several synthetic organic polymers that can be used to make different kinds of plastic materials and have resulted in billions of tons of waste that can reach the aquatic biome and are harmful to freshwater and marine communities as well as humans. Small pieces, known as microplastics, are very small (<5mm) and can readily be ingested by marine organisms, causing dangerous threats to the food supply chain. Although plastic debris appears as particles of varying size, shape, color, and chemical composition, its origin or source cannot easy be identified by the naked eye. Sometimes, it is also difficult to identify whether debris is made of plastics materials. However, plastic debris sources can be revealed by applying basic concepts of the interaction of infrared radiation with matter. If a sample is irradiated with infrared light, a part of the radiation can be absorbed and provide detailed information about the structure of chemical compounds, such as the arrangement of nuclei and chemical bonds within the molecule. Chemical features of a molecule allow identification of the type of polymer that makes up a plastic material. In this paper the authors describe a multidisciplinary approach to teaching the interaction of infrared light and the vibrating process of molecules to characterize plastic pollutants. The practical classes involve both indoor and outdoor activities, divided into four steps: choice of case study site; plastic debris sampling; sample preparation and physical and chemical characterization of plastic debris (size, color, shape and polymer type); data interpretation and identification of the main plastic debris sources. The first three steps, which include outdoor activities, can also be performed by students of all ages, as well as by geography, environmental science and biology teachers who are fundamental in multidisciplinary studies. The data interpretation step that involves the polymer identification is performed at the laboratory, by using ATR-FTIR and/or optical transmittance sensor systems. Finally, the identification of the main plastic debris sources and the final conclusions are tasks that can be performed in a multidisciplinary way.

Radon is a dangerous radioactive gas that is always present in the environment. It is important that students and society in general are aware of radon as a health hazard. This study describes a simple experiment to measure the variations of radon gas concentration outdoors. We compared the concentration of radon gas in the environment in dry and wet weather conditions and at different times of day. The results show that outdoor radon concentrations are significantly lower, by as much as 50%, during cloudy and rainy conditions.

Ionizing radiation one of modern physics experimental teaching in colleges and high school can be easily implemented today due to low coasts of detectors and also electronic circuits and data acquisition interfaces. First it is interesting to show to young's students what is ionizing radiation and from where they appears near ground level? How it is possible to measure these radiations and how to check intensities variation during day, night, dry and wet periods in the same school? For increasing interest and stimulation in others students how to proceed in making the graphics of the ionizing radiation and presenting him in real time using Web internet facilities? Many others facilities like calibration of the detector using low intensities radioactive ionizing radiation sources, make comparison of the measurements and discussions of the results should be possible between many groups of students from several schools in the region of Brazil. This paper presents the experimental procedures including detectors and associated electronic including data acquisition, graphics elaboration and Web internet procedures to discuss and exchanging data measurements from several schools.

In the Cerrado-Amazonian ecotone in the State of Mato Grosso, intensely altered by anthropic action, the knowledge and processes of energy conversion and energy balance are still incipient, making the monitoring and modeling of diffuse radiation essential for several applications. The objective of this study was to evaluate the seasonality of the diurnal evolution and estimate the hourly diffuse radiation ( H d h) and incident radiation in the horizontal plane between June 2011 and October 2016. The instantaneous measurements (5 min) of diffuse radiation underwent geometric, astronomical, and anisotropic corrections, with subsequent hourly integrations. The seasonality of diffuse radiation and its radiometric fractions was evaluated. The estimates were made considering total and seasonal data groupings (water stations in the region) and in different cloudiness classes (atmospheric transmissivity index— K T h ). The diurnal behavior of diffuse radiation ( H d h ) was similar to that of global radiation and at the top of the atmosphere, with maximum values at solar noon. The correlations between K d h and K T h showed third-order polynomial behavior, with maximum observed values of K d h ranging from 0.8 to 0.9, for K T h less than 0.2. Estimation equations based on radiometric fractions underestimated the values of diffuse radiation, with a better performance presented by models adjusted in annual data groupings. Among the parameterized models for estimating diffuse radiation obtained in the literature, those calibrated regionally in this study, together with those developed for tropical regions, presented better statistical performances. [ABSTRACT FROM AUTHOR]

Comprising the oldest unequivocal dinosauromorphs in the fossil record, silesaurs play an important role in the Triassic radiation of dinosaurs. These reptiles provide the main source of information regarding the ancestral body plan of dinosaurs, as well as the basis for biogeographic models. Nevertheless, the co-occurrence of silesaurs and the oldest unequivocal dinosaurs is rare, which hampers reliable ecological inferences. Here we present the first species of silesaur from the oldest unequivocal dinosaur-bearing beds from Brazil. Amanasaurus nesbitti gen. et sp. nov. possesses a unique set of femoral traits among silesaurs, including the oldest occurrence of an anterior trochanter separated by the femoral shaft by a marked cleft. Its femoral length indicates that the new species rivals in size with most coeval dinosaurs. This find challenges the assumption that in faunas where silesaurs and unambiguous dinosaurs co-occurred, silesaurs were relatively smaller. Moreover, the presence of dinosaur-sized silesaurs within ecosystems with lagerpetids, sauropodomorphs and herrerasaurids reinforces the complex scenario regarding the early radiation of Pan-Aves. Silesaurs—independent of their phylogenetic position—persisted during most of the Triassic Period, with its plesiomorphic body size advancing through the dawn of dinosaurs, instead of silesaur lineages decrease in body size through time. [ABSTRACT FROM AUTHOR]

The State of Alagoas dedicates 1o,95% of its area to the cultivation of sugar cane (Saccharums sp.). Soil heat flux (SHF) is a crucial component of net radiation (Rn), which also varies due to changes in vegetation cover. This experiment was carried out in an area of experimental sugar cane cultivation in the municipality of Rio Largo (09°28'03" S, 35°49'49" W) from November 2017 to November 2018. The aim was to characterize SHF and Rn under different degrees of soil vegetation cover in the Coastal Tablelands of the Alagoas state, Brazil. Net radiation components were measured using a Kipp and Zonen CNR1 net radiometer, whereas SHF was measured using three HFT-3 plates (REBS, Campbell Scientific Inc., USA), which were installed at a depth of 0.05 meters. The predominant atmospheric transmittance (Kt) classification was partly cloudy (54.70%). Precipitation, along with cloudiness, incident solar radiation, and land cover, influenced the seasonal cycle of net radiation (Rn) and soil heat flux (SHF). On average, the removal of vegetation cover had a negligible impact on Rn, whereas it led to a 437% increase in SHF during the day and a 240% increase during the night. [ABSTRACT FROM AUTHOR]

The Brazilian coast is rich in monazite which is found in beach sand deposits. In this study, the composition of the monazite sands from beaches of State of Espírito Santo, Brazil, was investigated. The concentrations of rare earth elements (REEs), Th, and U were determined by inductively coupled plasma mass spectrometry (ICP-MS). In the studied region, the mean concentration of investigated elements increased in the following order: Tm < Yb < Ho < Lu < Eu < Er < Tb < Dy < U < Y < Th < Gd < Sm < Pr < Nd < La < Ce. The sampling sites were classified into three clusters and discriminated by the concentrations of REEs, Th, and U found. In general, the radiological risk indices were higher than the established limits, and the risk of developing cancer was estimated to be higher than the world average. [ABSTRACT FROM AUTHOR]

The Caatinga biome, characterized by its dynamic vegetation due to climate and land use changes, experiences varied environmental responses during the dry and rainy seasons. This research aims to dissect the complexity of surface radiation fluxes, vapor pressure, and air and soil temperatures across three distinct vegetation densities within the Caatinga: recovering, degraded, and preserved. Utilizing data from Moderate Resolution Imaging Spectroradiometer/Enhanced Vegetation Index products to analyze these densities offers a novel lens through which to view the biome's reaction to climatic shifts. Our findings unveiled specific patterns of solar and longwave radiation fluxes that correlate with key climatic variables like air temperature and surface albedo. This investigation not only addresses a critical gap in our knowledge of a globally significant but underexplored biome, but it also advances our comprehension of how vegetation density influences radiation fluxes in arid settings. Insights from this study are vital for forecasting and mitigating the ecological and climatic impacts of land cover transformations in semiarid regions worldwide. Significantly, the degraded site displayed nearly double the solar radiation reflection (138 Wm−2) compared to the recovering site (68 Wm−2), underscoring the role of vegetation density in modulating local climate conditions, despite atmospheric consistency across the study sites. [Display omitted] • The Caatinga biome covers the world's most densely populated dry region. • The study observes radiation fluxes over different vegetation densities. • Recovering and degraded vegetation had higher incoming solar radiation. • Preserved Caatinga areas emitted the most intense longwave radiation. • Degraded Caatinga showed the highest surface albedo values. [ABSTRACT FROM AUTHOR]

The objective of this paper was to study the radiation interaction parameters and the degree of weathering of horizons of a Cambisol located in a conservation unit using the percentages of oxides. The oxide contents of the horizons were obtained by employing ED (energy dispersive) and WD (wavelength dispersive) X-ray fluorescence (XRF) techniques, considering that their interpretation of the weathering indices differs according to their resolution. The radiation interaction parameters were calculated using the XCOM computational code, which allowed us to obtain the following parameters: µ/ρ (mass attenuation coefficient), σA and σE (atomic and electronic cross section), Zeff (effective atomic number) and Nel (electronic density). The results indicated that although both techniques proved to be efficient in detecting the levels of oxides, WDXRF was more sensitive. Fe2O3 showed great influence on the parameters µ/ρ, σA and σE, while Zeff and Nel presented no correlations. However, the curves of Zeff and Nel, in the studied energy range (1–100 keV), showed a better distinction between them when compared to the other parameters. The studied Cambisol presented a preserved structure, since it belongs to a conservation unit. Therefore, our findings should be considered a reference result for soils in the region with the same classification and origin, but which were subjected to anthropic action. [ABSTRACT FROM AUTHOR]

Dragon fruit cultivation in Brazil has been growing and the increase in consumption is associated with the nutritional benefits and attractiveness of the fruit. However, information on the fruit postharvest behavior relative to its conservation potential and technologies is incipient. In this context, this study aimed to evaluate the postharvest quality of red dragon fruit submitted to different doses of UV-C radiation. The fruits were obtained from a commercial orchard in the rural area of Piracanjuba-GO, Brazil. The experiment was conducted in a completely randomized design in a 4x9 factorial scheme, with four radiation doses (0, 1.81, 3.62, and 7.24 kJ m-2) and nine days of analysis (0, 2, 4, 6, 8, 10, 12, 14, and 16 days). After radiation, one fruit was packed per low-density polyethylene (LDPE) package, which was refrigerated and stored in a BOD at 8±1 °C and 60±4% RH. Weight loss, postharvest conservation, soluble solids content, pH, titratable acidity, maturation index, color (°hue and chroma), betacyanins, and carotenoids were evaluated. The data were subjected to analysis of variance (P<0.05) and, when significant, to regression analysis. The dose of 1.81 kJ m-2 stood out for maintaining the red dragon fruit quality. The red dragon fruit, whether or not treated with UV-C radiation, packed in LDPE, can be maintained refrigerated for up to 21 days without deteriorating. [ABSTRACT FROM AUTHOR]

Copyright of Revista Gaucha de Enfermagem is the property of Revista Gaucha de Enfermagem and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simultaneous cultivation of agricultural and forest species may result in changes in plant community interactions, generating microclimatic changes within the understory and then modifying growth and yield characteristics of the intercropping systems. Thus, this study aimed to assess the radiation use efficiency, growth and yield of bean and soybean cultivated in succession under two arrangements of agroforestry and full sun. To these ends, two field experiments were conducted in Southern Brazil: bean in‐season and soybean off‐season. Absolute and relative growth rates, net assimilation rate, leaf weight ratio, leaf area ratio, specific leaf area, radiation use efficiency and yield of bean and soybean were assessed. The solar radiation flux was modified by plant arrangement and tree canopy characteristics. Shading affected growth and yield characteristics and the radiation use efficiency of the studied crops. From the results obtained in this study, it is possible to recommend crop bean cultivation in agroforestry systems. However, for soybean, due to the reduced yields obtained in agroforestry systems, further research should be conducted in order to study more spaced arrangements and crop insertion in the early years of agroforestry, in order to enable its insertion in agroforestry systems in Southern Brazil. [ABSTRACT FROM AUTHOR]

This article deals with "radiação" or radiation as a process that creates bond and distance between people and spiritual entities -- souls, spirits, and "caboclos" -- and between these entities themselves. Drawing on ethnographic research conducted in Andaraí, a city in the Chapada Diamantina region, located in the northeast of Brazil, it presents a range of variations around the radiation in two contexts: in the "jarê", an African-based religion, and in the mourning ritual called "terno das almas". The radiation is often defined as a stage prior to possession, being an experience underlined by ambivalence and uncertainty of the entities' presence in people's bodies and practices. In this paper, I will argue that the radiation experience can also be thought of as a way of being in a relationship with these entities, demanding attention, knowledge, and zeal. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Statement of the Problem: Non-syndromic cleft lip and palate are the most frequent craniofacial abnormalities in humans. The genetic, environmental and behavioral factors involved in this malformation must be clarified in different parts of the globe in the view of implementing preventive measures. Purpose: To analyze the influence of parental exposure to risk factors on the occurrence of oral clefts. Materials and Method: A case-control study was conducted with 150 mothers of oral cleft children paired by the children's gender to 300 mothers of children without congenital anomalies from Mato Grosso, Brazil, for the study of the variables: gender and race/color of the children; parental educational level; age; number of pregnancies; prenatal care; obesity; stress; diabetes; hypertension; use of medications, alcohol and illicit drugs; smoking and exposure to ionizing radiation during the first trimester of pregnancy. The results were analyzed in relation to the chances possibility of each variable for the occurrence of oral cleft through the bivariate and multivariate analysis by applying the model of logistic regression. Results: Passive smoking, obesity, exposure to ionizing radiation and use of antibiotics were associated with the presence of clefts. The use of folic acid and analgesics were identified as preventive factors. The father's low educational level was found as a risk factor, while the black race/color was a preventive factor; nevertheless these variables were not associated in the multivariate analysis. Conclusion: The results reinforce the need to follow up the pregnant women, especially in the first trimester of pregnancy, in order to control the identified risk factors. Considering the factors associated with occurrence of oral clefts and those associated with its prevention, it is possible to apply specific health promotion measures during pregnancy, which can result in the reduction of oral clefts' occurrence. [ABSTRACT FROM AUTHOR]

The Brazilian solar energy potential presents an annual average considerably high compared with Germany, which receives 40% less radiation than the least sunny place in Brazil and, even so, is at an advanced stage of research and facilities. The cooperation between Brazil and Germany promotes important results for the development of solar energy in the country. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia, Cuidado e Saude is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Predatory dinosaurs were an important ecological component of terrestrial Mesozoic ecosystems. Though theropod dinosaurs carried this role during the Jurassic and Cretaceous Periods (and probably the post-Carnian portion of the Triassic), it is difficult to depict the Carnian scenario, due to the scarcity of fossils. Until now, knowledge on the earliest predatory dinosaurs mostly relies on herrerasaurids recorded in Carnian strata of South America. Phylogenetic investigations recovered the clade in different positions within Dinosauria, whereas fewer studies challenged its monophyly. Although herrerasaurid fossils are much better recorded in present-day Argentina than in Brazil, Argentinean strata so far yielded no fairly complete skeleton representing a single individual. Here, we describe Gnathovorax cabreirai, a new herrerasaurid based on an exquisite specimen found as part of a multitaxic association form southern Brazil. The type specimen comprises a complete and well-preserved articulated skeleton, preserved in close association (side by side) with rhynchosaur and cynodont remains. Given its superb state of preservation and completeness, the new specimen sheds light into poorly understood aspects of the herrerasaurid anatomy, including endocranial soft tissues. The specimen also reinforces the monophyletic status of the group, and provides clues on the ecomorphology of the early carnivorous dinosaurs. Indeed, an ecomorphological analysis employing dental traits indicates that herrerasaurids occupy a particular area in the morphospace of faunivorous dinosaurs, which partially overlaps the area occupied by post-Carnian theropods. This indicates that herrerasaurid dinosaurs preceded the ecological role that later would be occupied by large to medium-sized theropods. [ABSTRACT FROM AUTHOR]

• Theoretical model for organic PV module P3HT:PCBM. • Experimental determination of equivalent circuit parameters of organic PV module. • Reduced dependence of V OC on module temperature observed. • Long-term tests performed using fixed voltage method for obtaining energy yield. In this work the behavior of an organic solar module operating under real solar radiation conditions is presented. This allows to understand which parameters limit the efficiency of an organic device and their underlying mechanisms. The characterization of a module, produced by CSEM Brasil, with active layer P3HT:PCBM, is based on instantaneous voltage and current curves, dark current curves and analysis of the module operating continuously with fixed voltage. This allows to extract the parameters of the equivalent circuit of the module, such as diode saturation current (I 0), series resistance (R S) and shunt resistance (R SH) as well as to understand the influence of different levels of radiation and temperature on such parameters. The work presented was performed by using a commercial organic solar module in extensive outdoor experiments. The results are based on continuous use and for several levels of radiation and temperature under real operating conditions in comparison with a theoretical model for the first time. With the continuous tests it was possible to demonstrate the average daily generation of the module in Wh/m2, and also to verify experimentally, that the module presents better efficiency for diffuse radiation. [ABSTRACT FROM AUTHOR]

Physalis peruviana L. is a species of commercial interest belonging to the Solanaceae family, cultivated preferentially in shaded environment, which still has cultivation restricted to small areas in Brazil and therefore requires further studies. Plants are directly affected by environmental factors such as drought, temperature, radiation, among others. These factors affect not only the vegetative organs, but also reproductive structures, which may cause damage to agronomically explored plants. With the need for shading presented by the crop, the present work aimed to characterize the pollen grain and to verify the influence of shade nets used in shading on the morphology of pollen grains of this species. The work was developed at the Lavras Federal University, where three replications of two plants were cultivated under full sun and under shadenets white, blue, red and black. Flower anthesis pollen was collected, processed and photographed by scanning electron microscope (SEM). Polar diameter, equatorial diameter and pollen area were measured in ten pollen grains. The results showed that P. peruviana pollen grains are isopolar, radial, prolato-spheroidal in shape and medium in size. There was also an increase in pollen grain area when cultivated in shading with white shade net and in full sun. [ABSTRACT FROM AUTHOR]

The objective of this study was to measure the intensity of photosynthetically active radiation (PAR), ultraviolet A (UVAR) and ultraviolet B (UVBR) for one year (May to December 2013 and January to April 2014) in Florianópolis. Measurements were performed every Monday, Wednesday and Friday at 1-hour intervals from 10:00 a.m. to 2:00 p.m. The highest intensities of PAR were observed in January, followed by February, November and December. The highest intensities of UVAR occurred from September to February, and for UVBR, from November to February. Taking into account the time, the incidences of PAR showed no statistical difference, UVAR intensities were higher than those of UVBR during all months and at all times. For UVAR the incidence peaks occur at noon, while the UVBR was more constant during measured times. Seasonally, it was noted that the highest indices of PAR, UVAR and UVBR occurred in summer. [ABSTRACT FROM AUTHOR]

There has been a growing demand on energy sector for short-term predictions of energy resources to support the planning and management of electricity generation and distribution systems. The purpose of this work is establishing a methodology to produce solar irradiation forecasts for the Brazilian Northeastern region by using Weather Research and Forecasting Model (WRF) combined with a statistical post-processing method. The 24 h solar irradiance forecasts were obtained using the WRF model. In order to reduce uncertainties, a cluster analysis technique was employed to select areas presenting similar climate features. Comparison analysis between WRF model outputs and observational data were performed to evaluate the model skill in forecasting surface solar irradiance. Next, model-derived short-term solar irradiance forecasts from the WRF outputs were refined by using an artificial neural networks (ANNs) technique. The output variables of the WRF model representing the forecasted atmospheric conditions were used as predictors by ANNs, adjusted to calculate the solar radiation incident for the entire Brazilian Northeastern (NEB) (which was divided into four homogeneous regions, defined by the Ward method). The data used in this study was from rainy and dry seasons between 2009 and 2011. Several predictors were tested to adjust and simulate the ANNs. We found the best ANN architecture and a group of 10 predictors, in which a deeper analyzes were carried out, including performance evaluation for Fall and Spring of 2011 (rainy and dry season in NEB, mainly in the northern section). There was a significant improvement of the WRF model forecasts when adjusted by the ANNs, yielding lower bias and RMSE, and an increase in the correlation coefficient. [ABSTRACT FROM AUTHOR]

Proposing solutions for potable water supply in semiarid regions such as Brazil's Northeast region is of great importance. In addition to the water shortage, the lack of chemical and biological quality in the water is another difficulty to be faced. Taking advantage of the high levels of solar irradiation in those regions, the use of solar systems for water treatment is possible. In this paper, an automated solar pasteurizer system was used for the microbiological decontamination of water. The main characteristics of the solar pasteurizer are energetic self-sufficiency and robustness, the ability to promote decontamination regardless of the turbidity or pH, absence of production of trihalomethanes, local biome preservation (Caatinga), control of treatment time and the absence of secondary contamination derived from the mixture of contaminated water with water in treatment. The system was able to treat the water in pre-programmed temperatures and time intervals of 3600 s at 55 °C; 2700 s at 60 °C; 1800 s at 65 °C; 900 s at 75 °C; and 15 s at 85 °C. The microbiological analysis performed (presence/absence of Total Coliforms and Escherichia coli ) indicated the efficacy of the system, making it suitable for water treatment. It was found that productivity (batches' frequency) is directly proportional to accumulated irradiation. The pasteurizer is able to treat the water starting at the solar irradiation level of ≥12.2 MJ/m 2 for systems without a heat recovery exchanger. The use of a heat recovery exchanger in this system, to pre-heat the water at the collector's inlet, is of great importance because it induces an increase in productivity of approximately 50% (highest productivity reaching 30 L in a day) and lowers the minimum level of solar irradiation 8.3 MJ/m 2 . [ABSTRACT FROM AUTHOR]

Radiative cooling (RC) can provide free cooling by emitting radiative heat into outer space. This article presents the effects of solar radiation, non-radiative heat gains, atmospheric conditions, and spectral selectivity on the performance of radiative cooling technologies. Radiative cooling materials, including polymeric structures, pigmented paints, and photonic structures, are also reviewed. The benefits of integrating RC structures into buildings are reviewed, including estimates of energy and cost savings, and payback period. Methods for determining the global warming potential (GWP) when carrying out a life-cycle assessment (LCA) for RC structures are also presented. These LCA methods include two primary mechanisms through which radiative cooling technologies reduce GWP: 1) by directly reducing radiative forcing by radiating energy to outer space, and 2) by indirectly reducing radiative forcing by decreasing cooling loads, which reduces the CO 2 emissions associated with providing power for cooling. Estimates for exemplary case studies show that by installing radiative cooling technologies the GWP for cooling houses in Jamaica, Ghana and Brazil over a 20 year period can be reduced by ∼40,000 kg CO 2-eq , ∼14,000 kgCO 2-eq , and ∼22,000 kgCO 2-eq , respectively. In most cases, the dominant reason for the decrease in the GWP is the reduction in CO 2 emissions achieved by reducing the building cooling load. However, the emission of long wavelength radiation and the corresponding reduction in radiative forcing is significant and is the dominant factor reducing the GWP for some cases. The limitations and future prospects for RC technologies in building applications are also discussed. • Detailes of radiative cooling principles and underlying heat transfer modes are reviewd. • A comprehensive review of the recent radiative cooling structures. • Applications of integrating radiative cooling into buildings and their benefits. • New methods to account for the effects of radiative cooling on radiative forcing in LCA studies. [ABSTRACT FROM AUTHOR]

Abstract: Highlights of findings on radiological measurements, radiobiological and epidemiological studies in some main world high background natural radiation (HBNR) areas such as in Brazil, China, India and Iran are presented and discussed with special regard to remediation of radiation exposure of inhabitants in such areas. The current radiation protection philosophy and recommendations applied to workers and public from operation of radiation and nuclear applications are based on the linear non-threshold (LNT) model. The inhabitants of HBNR and radon prone areas receive relatively high radiation doses. Therefore, according to the LNT concept, the inhabitants in HBNR areas and in particular those in Ramsar are considered at risk and their exposure should be regulated. The HBNR areas in the world have different conditions in terms of dose and population. In particular, the inhabitants in HBNR areas of Ramsar receive very high internal and external exposures. This author believes that the public in such areas should be protected and proposes a plan to remedy high exposure of the inhabitants of the HBNR areas of Ramsar, while maintaining these areas as they stand to establish a national environmental radioactivity park which can be provisionally called “Ramsar Research Natural Radioactivity Park” (RRNRP). The major HBNR areas, the public exposure and the need to remedy exposures of inhabitants are reviewed and discussed. [Copyright &y& Elsevier]

Copyright of Rev Rene is the property of Rev Rene and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The genus Alcantarea comprises near 30 species endemic to rocky outcrops from eastern Brazil. Most species are ornamental and several are threatened due to habitat loss and over collection. In this paper we examine the phylogenetics of Alcantarea and its relationship with the Brazilian members of Vriesea, a genus of which Alcantarea has been treated as a subgenus. We discuss the morphological evolution of the stamen position and its implication for pollination and the occurrence of Alcantarea in the Espinhaço mountain range rocky savanna-like habitat vegetation. DNA sequence data derived from two plastid markers (trnK-rps16, trnC-petN) and from a low copy nuclear gene (Floricaula/Leafy) together with 20 nuclear microsatellite loci were the data source to perform analyses and construct phylogenetic and Neighbor Joining trees for the genus. Alcantarea is well supported as monophyletic in both Bayesian and parsimony analyses, but sections of Vriesea, represented by the eastern Brazilian species, appear paraphyletic. Microsatellites delimit geographically isolated species groups. Nevertheless individuals belonging to a single species may appear related to distinct clusters of species, suggesting that hybridization and/or homoplasy and/or incomplete lineage sorting are also influencing the analysis based on such markers and may be the reasons for some unexpected results. Alcantarea brasiliana is hypothesized as putative hybrid between A. imperialis and A. geniculata. Spreading stamens, a morphological floral characteristic assumed to be related to Chiropterophily, apparently evolved multiple times within the genus, and invasion of rocky savanna-like habitat vegetation by Atlantic rainforest ancestors seems to have occurred multiple times as well. [Copyright &y& Elsevier]

Objective. Measure physical therapists' exposure to the electric and magnetic fields produced by 17 shortwave diathermy devices in physical therapy clinics in the city of Presidente Prudente, São Paulo State, Brazil. Compare the observed values with the exposure levels recommended by the International Commission on Non-ionizing Radiation Protection (ICNIRP). Observe the efficacy of Faraday cages as a means of protecting physical therapists from exposure to oscillating electric and magnetic fields. Methods. Electric and magnetic field measurements were taken at four points during actual physical therapy sessions: in proximity to the operator's pelvis and head, the devices' electrical cables, and the electrodes. The measuring equipment was a Wandel & Goltermann EMR-200. Results. The values obtained in proximity to the electrodes and cables were 10 to 30 times higher than ICNIRP's recommended occupational reference levels. In the short-wave diathermy treatment rooms with Faraday cages, the fields were even higher than in treatment rooms not so equipped--principally the magnetic field, where the values were more than 100 times higher than the ICNIRP exposure limit. Conclusions. The electric and magnetic field intensities obtained in this study are generally above the exposure levels recommend in ICNIRP standards. It was also observed that the Faraday cage offers physical therapists no protection, and instead, increases their level of exposure. [ABSTRACT FROM AUTHOR]

The article presents a case study on determining the dissolution parameters of uranium oxide (UO), in a Brazilian nuclear fuel factory or pellet plant. For determining solubility parameters, a static dissolution test in vitro was used and Gamble's solution as the simulated lung fluid (SLF). It concludes by stating that the use of specific parameters provided a more realistic assessment of the worker's risk due to inhalation of airborne particles containing uranium.

The main goal of this work is to describe the anthropogenic energy flux ( Q) in the city of São Paulo, Brazil. The hourly, monthly, and annual values of the anthropogenic energy flux are estimated using the inventory method, and the contributions of vehicular, stationary, and human metabolism sources from 2004 to 2007 are considered. The vehicular and stationary sources are evaluated using the primary consumption of energy based on fossil fuel, bio fuel, and electricity usage by the population. The diurnal evolution of the anthropogenic energy flux shows three relative maxima, with the largest maxima occurring early in the morning (∼19.9 Wm) and in the late afternoon (∼20.3 Wm). The relative maximum that occurs around noontime (∼19.6 Wm) reflects the diurnal pattern of vehicle traffic that seems to be specific to São Paulo. With respect to diurnal evolution, the energy flux released by vehicular sources ( Q) contributes approximately 50% of the total anthropogenic energy flux. Stationary sources ( Q) and human metabolism (Q) represent about 41% and 9% of the anthropogenic energy flux, respectively. For 2007, the monthly values of Q, Q, Q, and Q are, respectively, 16.8 ± 0.25, 14.3 ± 0.16, 3.5 ± 0.03, and 34.6 ± 0.41 MJ m month. The seasonal evolution monthly values of Q, Q, Q, and Q show a relative minimum during the summer and winter vacations and a systematic and progressive increase associated with the seasonal evolution of the economic activity in São Paulo. The annual evolution of Q indicates that the city of São Paulo released 355.2 MJ m year in 2004 and 415.5 MJ m year in 2007 in association with an annual rate of increase of 19.6 MJ m year (from 2004 to 2006) and 30.5 MJ m year (from 2006 to 2007). The anthropogenic energy flux corresponds to about 9% of the net radiation at the surface in the summer and 15% in the winter. The amplitude of seasonal variation of the maximum hourly value of the diurnal variation increases exponentially with latitude. [ABSTRACT FROM AUTHOR]

This study had the objective to carry out a comparative study of Blaney Criddle, Hargreaves-Samani and Radiation methods with the standard method (Penman-Monteith FAO 56) for the climate conditions in the city of Uberaba, located in the "Triângulo Mineiro" region of the state of Minas Gerais, Brazil. A set of 10 years daily data (1996 to 2005) of maximum and minimum temperatures, wind speed, insolation and relative humidity was used. In order to compare the evapotranspiration values estimated by the empirical equations with the universal standard Penman-Monteith method (FAO56), the parameters of the regression equation a and b, determination coefficient, Pearson's correlation coefficient, mean bias error, the mean absolute error, root mean squared error, the index of agreement and the index of confidence or performance were considered. The methods were evaluated for two seasons: (1) low evaporative demand, in the months of April and September and, (2) high evaporative demand, in the months of October and March. In both cases, the Blaney Criddle equation was shown to be more accurate. The Hargreaves-Samani method presented the worst performance for the studied climate conditions. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on the long term effects of accidental exposures to ionizing radiation in Goiânia, Brazil in 1987, Yanango, Peru in 1999, and Concepción, Chile in 2005. Psychosocial problems were the most relevant issues in addition to recurrences of local radiation injuries in three Goiânian patients. The article points out that severe medical, psychosocial, environmental and economic impacts result from radiation accidents. Majority of accidents are blamed on gammagraphy.

Copyright of Revista Ciência & Saúde Coletiva is the property of Associacao Brasileira de Pos-Graduacao em Saude Coletiva and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two indigenous ceramics fragments, one from Lagoa Queimada (LQ) and another from Barra dos Negros (BN), both sites located on Bahia state (Brazil), were dated by termoluminescence (TL) method. Each fragment was physically prepared and divided into two fractions, one was used for TL measurement and the other for annual dose determination. The TL fraction was chemically treated, divided in sub samples and irradiated with several doses. The plot extrapolation from TL intensities as function of radiation dose enabled the determination of the accumulated dose (Dac), 3.99 Gy and 1.88 Gy for LQ and BN, respectively. The annual dose was obtained through the uranium, thorium and potassium determination by ICP-MS. The annual doses (Dan) obtained were 2.86 and 2.26 mGy/year. The estimated ages were ~1375 and 709 y for BN and LQ ceramics, respectively. The ages agreed with the archaeologists' estimation for the Aratu and Tupi tradition periods, respectively. [ABSTRACT FROM AUTHOR]

Abstract: An estimation of passive cooling techniques was conducted for 14 cities in Brazil, using a fairly accurate algorithm that accounts for heat conduction, convection, radiation, and evaporation; this was done to determine the amount of heat gain/loss of room air, defined as a particular quantitative index for passive techniques. Heat gains and losses were calculated for four envelope conditions – namely, insulated, high-albedo, wet surface, and a combination of the previous two – and compared to a case assumed to be the standard condition. A conclusion drawn was that a passive design is efficient in decreasing the need for cooling in typical dwellings in Brazil; solutions should differ with regional climate characteristics. In semi-arid areas, evaporative cooling showed the best results. Reduced heat gain was found during the warm seasons for all cities, along with increased heat gain during the cool seasons for mid-latitude cities. In particular, a combination of high-albedo enveloping and evaporation can greatly decrease heat gain in building walls. High-albedo surfaces in the sub-tropical areas found in southern Brazil are more efficient. It is suggested that passive techniques should be conceived in such a way so as to work during the cooling season and be disabled during mild ones. [Copyright &y& Elsevier]

The objective of this paper was to evaluate the influence of shading during the period of floral buds development on the growth and maturation of coffee fruits, production and grain size of Coffea arabica L. The experiment was carried out in Londrina, PR, Brazil. Plots of adult coffee plants were shaded monthly in April, May, June, July and August of 2004 using shading screens with 50% of porosity. The coverings were removed simultaneously at the beginning of October of the same year. The interception of 50% of incident radiation over the coffee canopy in different periods of floral buds development did not alter fruit growth and development. Fruit maturation was anticipated due to high temperatures and water deficit, however without significant differences on maturation periods among treatments. Grain yield and size were not affected by shading in the different periods. [ABSTRACT FROM AUTHOR]