Search

The present work sought to investigate the applicability of the microCT scanning beyond petrophysics in oil and gas industry. We analysed external features (morphology) with all their nuances, and internal features such as mineral inclusions and vugs, in micrometric alluvial gold grains from one of the largest rivers in Southeastern Brazil. Owing to the complicated X-ray interactions with any metallic material, mainly gold, several imaging protocols were used until obtaining the most appropriate one. The results corroborate that microCT scanning can be a useful tool in provenance studies of detrital gold grains, even in an adverse analytical context and with small gold grain populations. [ABSTRACT FROM AUTHOR]

Placer gold recovered from the Paraíba do Sul River, which flows along a high-grade shear zone in northern Rio de Janeiro, Brazil, has a distinctive component of palladiferous gold. Its finding, reported for the first time in the state of Rio de Janeiro, implies a hydrothermal system of high salinity at relatively low temperatures, in which metal transport is facilitated by hematite-rich rocks and generally precipitated at redox fronts. Such a hydrothermal system is not geologically manifested in the currently exposed high-grade shear zone. The finding of palladiferous gold suggests that its source was eroded during periods of increased denudation rates since the Lower Cretaceous, as indicated by apatite fission-track (AFT) data that have been reported for the region. [ABSTRACT FROM AUTHOR]

Copyright of Géneros: Multidisciplinary Journal of Gender Studies is the property of Generos: Multidisciplinary Journal of Gender Studies 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.)

Several gold deposits display complex Bi-bearing mineralogy. Bismuth-bearing phases are generally sensitive to changes in physicochemical conditions such that the interpretation of Bi–Au associations is useful to understand these mineralizing systems. However, gaps in the physicochemical constraints given by the Bi enrichment in these systems prevent robust metallogenic models in some complex deposits. São Sebastião is a hypozonal gold deposit in the Quadrilátero Ferrífero historic mining district in Brazil, and unlike other Archean gold deposits in this area, it displays a disseminated high-temperature and high-grade sulfide overprint with Bi enrichment. The Bi-bearing mineralogy at São Sebastião is heterogeneously distributed in the BIF-hosted ore bodies. Bismuth-sulfosalts, Bi-chalcogenides, and native bismuth have crystallized in a variable set of intercalated patches, yielding different ore facies given by the fractionation of hydrothermally assisted melts. Base metal–bearing Bi-sulfosalts, electrum, and acanthite result from high-temperature (~ 600 °C) immiscible melts rich in chloride ligands, while late crystallization of high-fineness native gold associated with native bismuth at 271 °C is evidence for Au scavenging by protracted low-temperature Bi-enriched metallic melts. This mechanism has favored gold remobilization from early sulfide assemblages and the development of localized upgraded ore stringers. Rapid uplift from a reduced (low fO2) hypozonal environment to oxidized brittle conditions is suggested by crosscutting bismuthinite-bearing veins' fluid inclusion patterns and the absence of maldonite (Au–Bi alloy). Many hypozonal deposits like São Sebastião show similar mineralogy and have developed at the boundaries of Archean terrains, registering multiple tectonic overprints where partial melts may have had an essential role in the final ore formation. [ABSTRACT FROM AUTHOR]

Halloysite is a 1:1 dioctahedral clay mineral that has been studied widely for applications in nanotechnology and as a mineral exploration guide for recognizing regolith-hosted heavy rare earth element (HREE) deposits. In Brazil, pegmatites from the state of Rio de Janeiro have been catalogued, but their potential to host halloysite deposits has never been studied. After a mineral exploration programme, one pegmatite with considerable halloysite contents and economic potential was discovered. This study reports the mineralogical and chemical characterization of the halloysite of this pegmatite and evaluates the possibility of clay-adsorbed HREE deposits, like that in the Zudong (China) regolith-hosted HREE deposit. Seven samples were collected in horizontal channels. Bulk samples and clay fractions (<2 µm) were analysed by quantitative mineral analysis (X-ray diffraction/Rietveld method), chemical analysis (major elements by X-ray fluorescence and Y, U, Th and rare earth elements by inductively coupled plasma mass spectrometry), scanning electron microscopy, Fourier-transform infrared spectroscopy, particle-size analysis, nitrogen physisorption and cation-exchange capacity. Mixed polygonal/cylindrical halloysite-7Å in concentrations between 6.3 and 35.4 wt.% in bulk samples and between 58.0 and 89.8 wt.% in the clay fractions were identified in the pegmatite. The clay fractions presented an average chemical composition of 45.46 wt.% SiO2, 36.10 wt.% Al2O3, 14.62 wt.% loss on ignition and 1.04 wt.% Fe2O3, as well as technological properties close to those observed in world-class halloysite deposits such as Dragon Mine (USA) and Matauri Bay (New Zealand). The clay minerals did not present significant HREE contents. [ABSTRACT FROM AUTHOR]

Copyright of Ceramica is the property of Associacao Brasileira de Ceramica 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.)

This research presents the mineralogical and chemical characterization and beneficiation study of two kaolin deposits from the Borborema Pegmatite Province, Brazil. Seven samples were collected and treated in two different beneficiation routes involving magnetic separation and chemical bleaching. The fractions obtained were studied by X-ray diffraction, X-ray fluorescence spectrometry, scanning electron microscopy, particle-size analyses, electron paramagnetic resonance and determination of optical properties. The samples are composed mainly of subhedral kaolinite in the form of booklets, as well as muscovite, quartz, microcline and illite impurities. The kaolinite structural formulae indicated significant replacement of Si4+ by Al3+ in tetrahedral sites and low replacement of Fe3+ by Al3+ in the octahedral sites. The first 30 min of chemical bleaching improved significantly the optical properties of kaolin, indicating that the process is more efficient than magnetic separation. [ABSTRACT FROM AUTHOR]

Water quality has declined globally due to increased contamination of aquatic ecosystems. The use of fish genotoxicity biomarkers may improve and complement parameters for environmental risk assessment. The aim of this study was to assess the genotoxicity of samples collected from streams of the Jordão River, a tributary of the Paranaíba River, Brazil with different levels of metal contamination, utilizing a native fish species to determine the sensitivity and viability of implementing a useful, reliable technique for routine biomonitoring programs. Chemical analysis of water and sediments collected from different sites indicated that a gradient of contamination existed as evidenced by different concentrations of metals detected. After chronic exposure to contaminated samples, micronucleus (MN) frequencies in fish erythrocytes were measured and correlation with environmental parameters determined. Sites where the water concentrations of the metals aluminum (Al), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) were high indicating a greater genotoxic potential of these elements. At the samples collected from the urban zone, a gradual increase was found for chromium (Cr), cadmium (Cd) and nickel (Ni) indicative of adverse impacts of discharge of urban effluents. Data demonstrated that Astyanax altiparanae, used in the test, exhibited a reliable sensitivity for detection of genotoxic consequences attributed to exposure to water samples collected near the discharge of industrial and domestic waste. [ABSTRACT FROM AUTHOR]

Copyright of Enfermagem Brasil is the property of Atlantica Editora 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.)

Background: The nematode Angiostrongylus cantonensis is a zoonotic parasite and the most important cause of eosinophilic meningitis worldwide in humans. In Brazil, this disease has been reported in the states of Espírito Santo and Pernambuco. The parasite has been detected in the naturally infected intermediate host, in the states of Rio de Janeiro, Pernambuco and Santa Catarina. The murid Rattus norvegicus R. rattus were recently reported to be naturally infected in Brazil. In this study, we conducted a two-year investigation of the dissemination pattern of A. cantonensis in R. norvegicus in an urban area of Rio de Janeiro state, Brazil, and examined the influence of seasonality, year, host weight and host gender on parasitological parameters of A. cantonensis in rats. Methods: The study was conducted in an area of Trindade, São Gonçalo municipality, Rio de Janeiro, Brazil. Prevalence of infected rats, intensity and abundance of A. cantonensis were calculated, and generalized linear models were created and compared to verify the contribution of host gender, host weight, year and seasonality to the variations in A. cantonensis abundance and prevalence in rats. Results: The prevalence of A. cantonensis infection was stable during the rainy (71%, CI 58.9- 81.6) and dry seasons (71%, CI 57.9-80.8) and was higher in older rats and in females. Seasonality, host weight (used as a proxy of animal age) and gender were all contributing factors to variation in parasite abundance, with females and heavier (older) animals showing larger abundance of parasites, and extreme values of parasite abundance being more frequent in the dry season. Conclusions: The high prevalence of this parasite throughout the study suggests that its transmission is stable and that conditions are adequate for the spread of the parasite to previously unaffected areas. Dispersion of the parasite to new areas may be mediated by males that tend to have larger dispersal ability, while females may be more important for maintaining the parasite on a local scale due to their higher prevalence and abundance of infection. A multidisciplinary approach considering the ecological distribution of the rats and intermediate hosts, as well as environmental features is required to further understand the dynamics of angiostrongyliasis. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Enfermagem Referência is the property of Escola Superior de Enfermagem de Coimbra 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 Acta Geográfica is the property of Acta Geografica 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.)

Summary: Conventional tillage may impose changes in soil physical properties that lead to a decrease in soil physical quality. Although plough pan formation is considered to be an important consequence of conventional tillage practices in Southeastern Brazil, few studies have focused on its hydrological consequences. Detailed investigations in two experimental plots located in the hilly landscape of Serra do Mar close to Rio de Janeiro city were carried out to characterize the changes in soil physical properties and in soil hydrology due to plough pan formation. Conventional (CT) and minimum tillage (MT) practices were implemented in two plots for 3years and soil matric potential (SMP) was monitored in each plot via nests of tensiometers and Watermark® sensors installed at different depths. Undisturbed soil blocks were collected for micromorphological analyses to quantify the total pore space in soils under CT and MT systems, and in soils under natural tropical forest. Results suggest that soils under the CT system developed a plough pan layer at about 20cm depth that had 44% less total porosity as compared to surface conditions. It is shown that soils under the CT system tended to stay saturated for longer periods of time after each rainfall event. Besides, during intense rainy periods soils under the CT system may develop hydrologic conditions that favor lateral flows while soils under the MT system were still draining. Such hydrological responses may explain why average soil erosion rates measured for individual rainfall events under the CT system were about 2.5 times greater than the ones observed at MT. The results attested that conventional tillage in this area generated modifications in soil fabric, especially in pore-size distribution and connectivity, which induced important changes in soil hydrology and soil erosion. The agricultural practices used in this area, associated with the local steep hillslopes and intense rainfall events, are definitely not adequate and require the introduction of soil and water conservation practices in order to become sustainable. [Copyright &y& Elsevier]

Abstract: Well characterized kaolin samples from different deposits of Brazil were studied by electron paramagnetic resonance. Three paramagnetic species attributed to iron in different chemical environments were identified in raw samples. A very intense and broad line with 0.2mT linewidth was typical of large particles of iron oxides/hydroxides. A species at g =2.0 with 0.04mT line width was associated with superparamagnetic particles adsorbed to kaolinite surfaces or trapped between its lamellae. An isotropic and/or orthorhombic species in the g =4.2 region belongs to structural Fe3+ replacing Al3+ in sites with different crystal-field symmetries. It was verified that large iron oxide particles were responsible for keeping the kaolin whiteness at levels below 50%. Superparamagnetic iron particles mainly affect whiteness in the range of 50%< whiteness <86%. They may be totally removed by magnetic separation followed by chemical treatment using sodium dithionite. The kaolin high whiteness levels (whiteness >86%) were determined by Fe3+ iron content in the kaolinite structure. However, only a small part of this species can be removed from the kaolinite structure by traditional industrial processing techniques. These results showed that EPR is a powerful technique to assist in controlling kaolin quality in industrial processes. [Copyright &y& Elsevier]

Copyright of Revista Brasileira de Crescimento e Desenvolvimento Humano is the property of Centro de Estudos de Crescimento e Desenvolvimento do Ser Humano 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 Psychosocial Care Centers for children and adolescents (CAPSi) are strategic elements of mental public health attention for children and adolescents suffering from persistent and severe mental disorders. They are articulated in a network that goes over the health field and interacts with the territory resources of a community in order to promote social inclusion of children and adolescents and they may also count on the partnership of families, society, schools and other sectors. In the list of their therapeutic practices there is specific time reserved to the attendance of families when it is considered a necessary measure for the children and adolescents in focus. Objective: to identify therapeutical practices offered to families of children and adolescents from CAPSi. Method: transversal study in children and adolescents who are assisted in CAPSi, selected randomly, from 19 CAPSi of São Paulo state from September 2008 to February 2009. The descriptive analysis was presented through tables with number and percentage. Results: mothers were shown as the main caregiver of the population studied. However, it is important to say that many files had no registration about attendance or proposals directed to the families. Conclusion: the main therapeutic practice indicated for families is group intervention. Families have not been privileged in the therapeutic practices in the projects of the population from CAPSi. Failures in files registration may have been a limitation of the study. The actions are preponderantly institutional and the activities out side of the service are incipient. [ABSTRACT FROM AUTHOR]

We investigated the prevalence and risk factors of anemia and iron deficiency in 398 rural Amazonians aged 5-90 years in Acre, Brazil. Anemia and iron deficiency were diagnosed in 16% and 19% of the population, respectively. Anemia was likely to have multiple causes; although nearly half of anemic school children and women had altered iron status indicators, only 19.7% of overall anemia was attributable to iron deficiency. Geohelminth infection and a recent malaria episode were additional factors affecting iron status indicators in this population. (Am J Public Health. 2007;97:237-239.) [ABSTRACT FROM AUTHOR]

The Codó Formation is an Aptian marine-influenced lacustrine depositional system in the Parnaíba Basin (Brazil). This unit is an important sedimentary succession because of the high organic matter content and for being an ancient analog for the depositional systems of the Brazilian Pre-salt interval. However, mineralogical and lithogeochemical studies have not been sufficiently carried out on the Codó Formation, which hinders detailed sedimentological knowledge. We report new mineralogical and lithogeochemical data that allow a better understanding of the environmental, climatic, and provenance evolution of the Codó deposits. Mineralogical and lithogeochemical studies were performed on 50 lutite samples collected from the 1-UN-32-PI core and 13 outcrop lutite samples obtained from sites close to the Grajaú and Imperatriz regions. A magnesium-sulfate-rich shallow alkaline hypersaline lake was identified in the lower Codó Formation based on the identification of a clay mineral assemblage composed of authigenic saponite and detrital illite. Hydrothermal processes were interpreted as the magnesium source of this alkaline lake. A salinity-alteration event was identified at the upper limit of the alkaline lake and was interpreted as the first marine ingression in the Codó Formation. This event changed the lake's pH from alkaline to acid, inhibiting the formation of Mg-smectites, and changing its hydrochemical conditions, originating a marine-influenced sulfate-rich acid saline/hypersaline sabkha. This facies succession coincides with a clay mineral assemblage composed of detrital montmorillonite, illite and kaolinite. A regional paleoclimate humidification process was identified from the sabkha to a lagoon facies succession in the upper Codó Formation. This last succession reveals the marine-dominated interval of the Codó Formation and coincides with a clay mineral assemblage composed of detrital kaolinite, montmorillonite and illite. Based on lithogeochemical data, a common post-Archean intermediate source area was also interpreted for these three environments. • The first characterization of Mg-smectites in the Aptian Codó Formation is presented. • An alkaline hypersaline lake in the lower Codó Formation caused by hydrothermal processes is described. • Marine ingressions were important triggers for environmental changes in the Codó Formation. • Regional climate change associated with the early onset of the Equatorial Humid Belt was recognized. [ABSTRACT FROM AUTHOR]

Abstract: Kaolin has been intensively used as an industrial mineral, mainly in the paper industry, as coating or filler material. In order to achieve the market requirements for this kind of use, there are several beneficiation processes that kaolin should pass, such as grain size classification, chemical bleaching and magnetic separation. In this work, mineralogical, chemical and physical characterizations were carried out in kaolin samples from the mined ore in Capim 1 deposit being commercially exploited by Pará Pigmentos S/A, before and after different steps of the industrial beneficiation processes. X-ray fluorescence and brightness measurement results indicate that all kaolin samples are typified by low iron content and high brightness grade. X-ray diffraction and scanning electron microscopy data exhibit kaolinite as the main mineral phase with minor amounts of quartz. The Hinckley index (>1.06) as determined with XRD shows that all samples exhibit high structural order. From electron spin resonance and 57Fe Mössbauer spectroscopy data we obtained essential information about the chemical nature of iron impurities. Results reveal that the highest improvement in kaolin properties is obtained when previous magnetic separation is included in the beneficiation. [Copyright &y& Elsevier]

The Aptian Crato Member of the Araripe Basin is a 50-m-thick succession of laminated limestones alternated with siliciclastic rocks. This unit has been receiving attention worldwide mainly because it is one of the most famous fossil Konservat - Lagerstätten , where were identified well-preserved paleofauna and paleoflora. Clay mineralogy and lithogeochemical data have been widely used in paleoenvironmental, paleoclimatic and provenance reconstructions. However, these techniques were not systematically used to study the Crato Member rocks. This study reports the mineralogical and lithogeochemical characterization of the Crato Member lutites looking for paleoenvironmental, paleoclimatic, and provenance reconstructions. Facies analysis, X-ray diffractometry, lithogeochemical, and scanning electron microscopy studies were carried out on thirteen Crato Member lutite samples in the Três Irmãos quarry, near Nova Olinda County. Regional arid paleoclimate conditions were identified using clay mineral assemblages and two paleoenvironmental models with subtle paleoprecipitation and provenance differences were interpreted. In the lower Três Irmãos quarry, a tidal-dominated delta mouth bar facies succession coincident with a clay mineral association with lesser kaolinite contents was identified, which indicates drier conditions. Lithogeochemical data suggests provenance from Archean felsic rocks. In the upper Três Irmãos quarry, a marginal paleolagoon facies succession coincident with a clay mineral association with higher kaolinite contents was recognized, which indicates wetter conditions. Lithogeochemical data indicate provenance from mixed Post-Archean to Archean felsic-mafic rocks. The paleolagoon water was interpreted as brackish and sudden paleosalinity increases indicated seawater inputs, which were also responsible for raising the paleolagoon water table in the marginal paleolagoon facies succession, which presented paleoenvironmental proxies suggesting a more expressive marine character. • Paleoenvironmental, paleoclimatic, and provenance differences between the upper and lower parts of Três Irmãos quarry. • Paleoenvironmental proxies indicating marine influence in the Crato Member. • New lithogeochemical data of the Crato Member lutites. [ABSTRACT FROM AUTHOR]

The Irati Formation documents a singular moment in the evolution of the Paraná Basin, when an effective restriction of water circulation between the syneclise and the Panthalassa Ocean finally established a favorable environment for the deposition of oil shales. The present study presents data from X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) for the determination of different mineralogical components in the entire interval of the Irati Formation. Seeking to correlate the varying mineralogical content of the formation with the paleoenvironmental, paleoclimatic and stratigraphic conditions, total organic carbon (TOC), total sulfur (S) and insoluble residue (IR) data were also utilized. The results showed that variations in mineralogical content occurred mainly in the interval where the greatest values of TOC, S and IR are found. The authigenesis of minerals such as analcime, pyrite, gypsite and barite are closely tied to the environment where they were formed, and these minerals bear within them characteristics of paleoenvironmental conditions, such as restricted water circulation, abundant organic matter, alkalinity and pelagic sedimentation. Variations in the mineralogical content of clay minerals point to an enrichment of illite in the upper interval of the Assistência Member, thus constituting a syndepositional process. The mineralogical data indicate a predominance of illite, chlorite and kaolinite in the Taquaral Member. However, clay mineral suite change in the different depositional domains of the Assistência Member: the internal platform has clay mineral suite dominated primarily by illite and saponite. Kaolinite increase in the intermediary platform and disappear in distal platform. The kaolinite increase probably is the result of intensified weathering due to increase temperature and precipitation. Kaolinite characterizes the transgressive systems tracts under warm and humid paleoclimatic conditions. In contrast, illite and saponite indicate warm and dry conditions in the highstand systems tracts. • The authigenic minerals related to alkaline and organic matter-rich environments with restricted water and pelagic sedimentation. • Illite concentration related to a syn-depositional process that has chlorite or even kaolinite as its precursor mechanism. • A change from illite- to kaolinite-dominated suites indicates a change in precipitation regime. • Kaolinite characterizes the transgressive systems tracts under warm and humid paleoclimatic conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adsorption of Nd species onto palygorskite is a favourable and endothermic process. • Q max was 18 mg/g; Nd removal higher than 99% was attained at pH 5. • Temkin isotherm model best fitted the experimental adsorption data. • Sorption of Nd3+ ions on PAL surface is complex, comprising more than one mechanism. • The sorption phenomena consider both monolayer adsorption and heterogeneous surface. Run-of-mine (ROM) palygorskite (PAL) from Guadalupes (Piauí/Brazil) was prepared, beneficiated and then properly characterized by physical–chemical analyses. Then, the removal of Nd3+ ions by PAL was evaluated as a function of solution pH, adsorbent concentration, and initial metal concentration. The results showed that the maximum sorption capacity was 18 mg/g, and more than 99 % of Nd was remove from the solution at pH 5. The sorption data were analysed by several isotherm models, but the better good of fitness (R2 ≥ 0.97; RMSE ≤ 0.98) was attributed to the Temkin model. It́s suggested that the adsorption process proceeds firstly by the introduction of the Nd ions into the interior and exterior pore of PAL, then the PAL surface acquires a negative charge by deprotonation of PAL actives sites (Me-OH), and then the capture of the Nd3+ ions on its inside and outside surface may take place through electrostatic interaction. Thermodynamic parameters indicated that the sorption process was favourable and endothermic. Thus, the present results pointed out that palygorskite has potential for removing Nd ions, and probable another rare earth elements from aqueous solutions, being a promisor adsorbent to the treatment of effluents containing neodymium, e.g. industry of permanent magnets. [ABSTRACT FROM AUTHOR]

The research aimed to evaluate the effect of row spacing and plant population on the production of sweet sorghum in sowing season and off-season crop. The experiments were conducted at Embrapa Maize and Sorghum, Sete Lagoas (MG) in an Oxisol in the 2011/2012 season. For two seasons of sowing, the plots were composed of five row spacings (50;60;70 and 80cm and double line 100x50cm), and sub-plots for four plant populations of sweet sorghum (80.000, 100.000, 120.000 and 140.000 plants ha-1). The experimental design was randomized blocks with three replications. It was used the variety of sweet sorghum BRS506. The experiment in the sowing season was implemented in November/2011 and the off-season in March/2012. The sowing season period resulted in higher fresh weight of total biomass, juice mass and Brix of sweet sorghum, regardless of plant arrangement. The row spacing of 50cm resulted in higher total biomass and juice mass ha-1, regardless of the period sowing. The double spacing resulted in values similar to the row spacing of 80cm for the main production variables, regardless of the period sowing. The plant population did not influence the yield of fresh mass of stems and juice mass, regardless of the period sowing. [ABSTRACT FROM AUTHOR]

This study consists of an ecotoxicological assessment related to one the most important environmental Brazilian disasters: the failure of an iron mining dam of the Vale S.A. in Brumadinho (Minas Gerais State, Brazil). Tailing samples (mixed with many other materials) were collected in three areas: (i) Zona Quente (n = 9) – close to the dam collapse; (ii) Parque das Cachoeiras (n = 3) – downstream of the Zona Quente; and (iii) Alberto Flores (n = 3), closer to Paraopeba river (an important tributary of one of the most important Brazilian watersheds). Acute ecotoxicological tests with Eisenia andrei and Daphnia similis and chronic reproduction tests with Folsomia candida and Chlorella vulgaris were performed. The bioassays with aquatic organisms were carried out with elutriates of the samples. Metal concentrations and physical, chemical and mineralogical properties of the samples were determined to support the interpretation of the ecotoxicological data. The increase of the particle density values (significantly correlated to an anomalous iron-enrichment and positive ΔpH values) seem to play a relevant role in the toxicity. As a result of iron-enrichment, the reduction of organic matter contents and water holding capacity were also crucial in the toxicity. Metal-enrichment factors showed abnormally high values, especially for Fe, Mn and Ni, while toxic metals concentrations exceeded the limits established by Brazilian law. Reproduction chronic effects were more intense than the acute ones, for both aquatic and soil organisms. Such extremely low reproduction levels of F. candida and C. vulgaris should be highlighted, since such organisms have a key ecological relevance. The samples collected in the Zona Quente were significantly different from the samples collected in downstream areas — fact that might be related to a high energy and turbulent flux of tailings in zones closer to dam, and the reduction of its energy in downstream areas. • First evaluation integrating toxic effects on soil and aquatic biota in Brumadinho • Toxic metals contents exceeded the limits defined by Brazilian law. • The iron contents played a crucial role in the terrestrial and aquatic toxicity. • Chronic ecotoxicological effects were more severe compared to the acute ones. • Materials deposited in areas closer to the dam are different from downstream ones. [ABSTRACT FROM AUTHOR]

Objectives to investigate the occurrence of the purple line and its respective discoloration in women during the active phase of labor and its association with dilation of the cervix and the position of the fetus in the pelvis, Methods: a descriptive. prospective, observational study was carried out in 100 women in labor at a normal delivery clinic in the State of Süo Paulo. Results: the purple line appeared in 56 of the 100 women in the active phase of labor There was a statistically significant correlation between the measurements for dilation of the cervix and those for the line; in 22% the purple line was discolored and there was no association between the number of women with this discoloration and the extent to which the head of the fetus had descended in the cervix. For 81% of the women in labor, the evaluation caused no discomfort whatsoever. Conclusions: as this line is present, measurement of it could be used to reduce the number of vaginal examinations, especially when the single aim is to measure dilation of the cervix. [ABSTRACT FROM AUTHOR]

Abstract: The technological characterization of kaolin from the Borborema–Seridó region has shown that it is predominantly kaolinitic, pseudoplastic and thixotropic; approximately 50% of its particles size is less than 2 μm. By using electronic paramagnetic resonance (EPR) and Mössbauer spectroscopy (ME), it was observed that Fe2+ and Fe3+ substitute Al3+ in octahedral sites of kaolinite. After magnetic separation followed by chemical bleaching, kaolin reached a brightness index of 87.72% ISO and an opacity index of 85.58% ISO, indicating that it can be used mainly as a filler and a coating in the paper industry, paint and pottery, among other industries. [Copyright &y& Elsevier]

This work aimed to evaluate the effect of acid mist on microbial communities developed on mortar with same composition from the wall of the National Museum in Rio de Janeiro. Five autochthonous microbial groups were inoculated on coated with acrylic paint and uncoated mortar surfaces and submitted to acid mist or water mist for 100 days. A heterogeneous biofilm was well developed in uncoated coupons under acid mist. Molecular analysis revealed that the bacterial communities were structured according to the incubation condition. The impact of coating on bacterial community structure was more important than the acid mist effect. The eukaryotic community structure was not affected by the acid mist, whereas the impact of coating by paint has been observed. The alpha diversity indexes also varied according to the treatment. H' and D were higher for uncoated conditions, particularly when submitted to acid mist. Actinobacteria, Chloroflexi, Cyanobacteria, Firmicutes and Proteobacteria were dominant. Additionally, eukaryotic community was not affected by the acid mist and paint and Tremellomycetes dominated. Image 1 • Evaluation of coating and acid mist in the mortar biodeterioration. • Experimental ecology, culture and molecular biology, and imagery provided good tools. • Acid mist promotes the development of microorganisms. • Bacterial and fungal communities were impacted by coating. [ABSTRACT FROM AUTHOR]

In São Pedro da Serra, district of Nova Friburgo/RJ, local farmers have been replacing the slash-and-burn cultivation agriculture because of current environmental laws. Moreover, the establishment of the Environmental Protection Area in Macaé de Cima imposed restrictions on the traditional agriculture practicese of the region. This paper aims at evaluating the phytosociological structure of three successional stages (Slash- and-burn I/4-7 years, Slash-and-burn II/10-12 years and Forest 50-70 years), the litterfall monthly production and its water holding capacity to investigate the sustainability of this agricultural practice. The structure of the arboreal component was determined by the delineation of three plots in each system, totaling 480 m². In each area, all individuals were mapped by the DBH (diameter at breast height, or 1,3m of soil) to ≥ 5cm. To quantify the monthly litterfall production, five collectors of 0,50 m2 were placed in each system(Proctor, 1983). Five seasonal samples were collected so that water holding capacity was measured And to measure the water retention capacity, seasonal five samples were collected in each system, with a square iron of 0.25 m2 (Vallejo, 1982). Seven different species in the PO I and PO II with the same dominant species (Machaerium stipitatum) were found, varying only in their representation in each system with 35% and 69% respectively. In the forest, Rubiaceae family presented highest number of individuals (54.3%). Concerning the exclusive species of each area, there were Croton floribundus in PO I, Solanum Argenteum in PO II and Guapira opposita in forest. As for water retention in the fall, the forest presented the highest retention rate, being followed by POII (26,52%) and POI (20,38%) The winter season shows the system POII (48.02%) with higher retention, followed by FL (38.46%) and POI (25.59%). The monthly output, FL showed the highest rate (19.77 g), followed by POI (14.99 g) and POII (10g). Regarding litter, it can be seen a different behavior that can be further defined by the completion of phytosociological studies. [ABSTRACT FROM AUTHOR]