Serra Dourada Research Articles

SOFTWARE DENTAL OFFICE: SEGURANÇA E ARMAZENAMENTO DE DADOS EM CLÍNICAS ODONTOLÓGICAS

Dental Office Software aims to organize and speed up the majority of services at the Dental Office, which is why it is important to use a system to control a company’s movements so that everything can be computerized, modern, better controlled and organized, making day-to-day life easier. day of the clinics. The objective of this work is to present the tools that the Dental Office application has for managing the Novos Ventos Dental Clinic at Faculdade Serra Dourada in Altamira-Pa, with an emphasis on the importance of digital security, protection of patient information, including compliance with the LGPD. 36 students from the dentistry course at Serra Dourada College who are between the 4th and 10th period participated in the research. The implementation of the same for the dental clinic will bring agility, security, greater storage capacity since the system was considered complete and suitable for the routine in the school clinic.

WATER STRESS IN MODERN UPLAND RICE CULTIVARS: A MULTIVARIATE STUDY BETWEEN PHYSIOLOGICAL TRAITS AND YIELD

Water stress negatively affects upland rice production. The objective of this study was to identify physiological traits that could depict yield responses under water stress conditions. Three modern upland rice cultivars (C) (BRS A501 CL, BRS Esmeralda and BRS Serra Dourada) were subjected to three water availability levels (W): Control (100% of the field capacity throughout the growing cycle) and 70 and 40% of the water applied to the control during flowering. Yield, spikelet sterility, and 1000-grain weight were influenced by the water availability level (p < 0.05), whereas for the cultivar, only 1000-grain weight was significant. The W × C interaction was not significant for the analyzed yield components. Multivariate analysis revealed that well-irrigated plants were positively associated with grain yield and gas exchange traits, whereas the 40% water availability level was highly related to spikelet sterility and the crop water stress index. The best-fitted model for grain yield was obtained using photosynthesis, stomatal conductance, and transpiration (R2 = 0.76). Thus, physiological parameters can be used to explain the variations in upland rice yield under water stress.

Still on the Stachytarpheta longispicata complex (Verbenaceae): two new narrowly endemic species from the Cerrado domain of Central Brazil

Among the Brazilian Stachytarpheta, the small group of species treated as the Stachytarpheta longispicata complex is morphologically recognised by its inflorescences with pedicellate flowers. This character is also present in S. longibracteata and S. rizzoi, two new species herein described based on the morphological species concept. Both species have a restricted distribution in the Cerrado domain, with S. longibracetata found in the Jalapão region (State of Tocantins) and S. rizzoi in the Serra Dourada region (State of Goiás). Detailed diagnosis, morphological comparisons, line drawings, ecological and taxonomic data, provisional conservation status, and a distribution map are provided for each new species. With these findings, we improve the taxonomy of the S. longispicata complex by increasing the number of known species to seven, and providing an identification key for this peculiar group with pedicellate flowers exclusive to the Cerrado.

The role of natural and anthropic factors in the variability of soil loss in the state of Goiás between 1985 and 2018

Soil loss depends on natural and anthropic factors with high spatial and temporal variability, and can be inferred by predictive models such as the Revised Universal Soil Loss Equation (RUSLE). In this sense, the objective of this work is to analyze the spatio-temporal distribution and variation of soil losses in the state of Goiás for the years 1985, 2000 and 2018, based on the application of RUSLE and using the drainage basin as a multiscale unit of analysis. The results generally show that there has beenan increase in the average loss of soils in the state between the observed years with the average in 1985 being 2.4 ton.ha-1.year-1, growing to 10.8 ton.ha-1.year-1 in 2000, and 11.56 ton.ha-1.year-1 in 2018. The hydrographic regions of Tocantins and Paraná presented the highest losses. In addition to the general control of the Cerrado conversion expansion, the state of Goiás presents two spatial soil loss patterns; one in which the control of natural factors predominates, being linked to morphogenetic aspects with a strong influence of the topographic factor; and the other being rain erosivity, spatialized in areas such as the “front” of Cuesta Caiapó, Serra Dourada and Serra dos Pireneus. When associated, these two factors define sensitive areas with the highest soil losses in the state of Goiás.

Impact of sowing dates on the yield efficiency of upland rice cultivars

The choice of cultivars adapted to different regions and the determination of the best sowing dates are indispensable tools for crop development. This allows the installation of the crop in times favorable to its development, as well as cultivars that manage to reach their maximum yield potential. The objective of this study was to determine the best sowing dates and the cultivars that can adapt to the low-altitude Cerrado region and have the best development and yield efficiency. The experiment was conducted on a typical clayey dystrophic Red Latosol soil. The experimental design was in randomized blocks in a factorial scheme, comprised by four sowing dates during the spring/summer season (October, November, December, and February) and in each sowing date there were eight upland rice cultivars (BRS Esmeralda, ANa 6005, ANa 5015, IPR 117, IAC 203, IAC 500, ANa 7211 and BRSGO Serra Dourada) with four replicates. Sowing in October and November benefited the aerial dry mass and the spikelets fertility however, sowing in November provided higher plant height, which caused lodging in plants. Sowing in December caused the incidence of scald, mainly affecting the cultivar ANa 7211. For all cultivars, sowing in October favored the yield efficiency of upland rice in the low-altitude Cerrado, followed by sowing in November. The cultivars which demonstrated higher yield efficiency in the conditions of the region were BRS Esmeralda and ANa 5015.

REE residence, behaviour and recovery from a weathering profile related to the Serra Dourada Granite, Goiás/Tocantins States, Brazil

The Serra Dourada Granite (SDG) is a roughly ellipsoidal massif with batholith dimensions that crop out in Goiás and Tocantins States, Central Brazil. It has been studied since the 1970′s due to its position in a complex geological framework, and exploited by both artisanal miners and mining companies, targeting mainly cassiterite. Circa 2008–2011, it begun to be systematically surveyed in respect to its REE occurrences, culminating in the Serra Verde Deposit, a REE ion adsorption-type mineralization hosted in a reddish coarse-grained biotite granite, the first of its kind in Brazil. Given that the massif has multiple facies, this paper reports the REE residence and behaviour along a weathering profile beyond the current limits of the Serra Verde Deposit, formed at the expense of a pinkish fine-grained muscovite-biotite granite, in order to verify its potential to host a similar mineralization. It also presents the results of a 2-step sequential leaching, to assess the REE recovery from the weathered material. Monazite-(Ce), xenotime-(Y), zircon, thorite, REE fluorocarbonates and fluorite were the main REE sinks identified at the base of the profile, where the parental granite occurs. In weathered samples from horizons above, monazite-(Ce), Th-rich monazite, xenotime-(Y), thorite, Ti-bearing Fe-oxide, cassiterite, Pb-rich cassiterite, Pb-oxide and zircon were the main accessory minerals. Whole-rock analyses in the parental granite reveals REE contents of 828 ppm, and the highest grade saprolite samples yields 1,075 ppm. The chondrite-normalized REE patterns of all samples shows that the granite is LREE-selective, as well as the patterns obtained after the complete extraction. Positive Ce anomalies characterize the upper samples, whereas negative Ce anomaly characterizes horizons below. The recovery rate of the weakly adsorbed REE ions (step-1) ranges from 16 to 31%, whereas step-2 (REE associated with Fe-oxides), extracts 44–57% relative to whole rock REE. XRD analyses reveals that kaolinite and illite are the most abundant clays in weathered samples, so that those clays are the main reservoirs that adsorb REE ions released from minerals during weathering. The accumulation of the LREE in the uppermost and lower half of the profile coupled with HREE depletion, arises from the different resistance to weathering of LREE- and HREE-enriched minerals in the bedrock and saprolite. The HREE higher affinity with complexants such as OH–, F and CO32– possibly present in percolating water may also play a secondary role in leaching them out contributing the the HREE depletion. The main conclusions of this study is that easily soluble LREE fluorocarbonates provide most of the REE to the weathering profile, and that the overall REE grade in saprock and saprolite is akin to other important ion-adsorption ores, although the REE contents in leachate solutions herein are somewhat lower than others. The exception is Ce, which contents and recovery, specially following step-2, are considerable.

Suscetibilidade à Erosão Laminar e Linear da Bacia Hidrográfica do Rio Vermelho e a sua Relação com o Uso e Cobertura da Terra em 2012

A perda de solos por erosão leva à redução da produtividade agrícola, e quando em um estágio avançado, impulsiona a degradação dos solos, tornando-os inaptos para o cultivo agrícola. Neste trabalho, buscou-se avaliar a suscetibilidade da Bacia Hidrográfica do Rio Vermelho (BHRV) a erosão laminar e a suscetibilidade a erosão linear da sub-bacia do Córrego Grande, localizada no compartimento de maior suscetibilidade da BHRV, com o intuito de identificar áreas mais propícias a ocorrência de focos erosivos. A alta bacia, que engloba os municípios de Goiás, Buriti de Goiás, Fazenda Nova, Novo Brasil e Mossamedes, foi o compartimento que apresentou a maior suscetibilidade a erosão laminar, devido à presença de solos de alta erodibilidade sobre um relevo de alta declividade, favorecendo o escoamento superficial em detrimento da infiltração de água no solo. Neste compartimento, as áreas de pastagem localizadas na Serra de Santa Rita em Faina e na Serra Dourada em Goiás tiveram alguns terrenos cujo uso do solo foi incompatível com a suscetibilidade à erosão laminar, apresentando alto potencial para a ocorrência de focos erosivos de origem laminar. Já a menor suscetibilidade à erosão laminar ocorreu na baixa bacia, em particular nos municípios de Britânia e Aruanã, por ser esta uma área de relevo plano de baixas altitudes sobre depósitos sedimentares recentes. Comparando a suscetibilidade a erosão laminar com a linear para a sub-bacia do Córrego Grande, diferentemente da primeira, a suscetibilidade a erosão linear é maior em declividades intermediárias (7-17%), as quais favorecem uma maior concentração do escoamento superficial.Palavras-chave: Erosão, Bacia Hidrográfica do Rio Vermelho, Declividade, Comprimento de Rampa, Sub-bacia do Córrego Grande. Susceptibility of the Red River Basin to Laminar and Linear Erosions and its Relationship to Land Use and Land Cover in 2012 A B S T R A C TLoss of soil by erosion leads to reduced agricultural productivity, and when at an advanced stage, it drives soil degradation, rendering it unfit for agricultural cultivation. The objective of this work was to evaluate the susceptibility of the Rio Vermelho Hydrographic Basin (BHRV) to laminar erosion and the susceptibility to linear erosion of the Córrego Grande sub-basin, located in the most susceptible compartment of the BHRV, in order to identify favorable areas to erosion. The high basin, which encompasses the municipalities of Goiás, Buriti de Goiás, Fazenda Nova, Novo Brasil and Mossamedes, was the compartment that presented the greatest susceptibility to laminar erosion, due to the presence of soils of high erodibility on a relief of high slope, favoring the superficial flow in detriment to the infiltration of water in the soil. In this compartment, pasture areas located in Serra de Santa Rita in Faina, and Serra Dourada in Goiás, had some terrain whose soil use was incompatible with the susceptibility to laminar erosion, presenting high potential for the occurrence of erosive foci of laminar origin. The lowest susceptibility to laminar erosion occurred in the low basin, particularly in the municipalities of Britania and Aruanã, because it is a flat relief area of low altitudes on recent sedimentary deposits. Comparing susceptibility to laminar erosion with linear erosion for the Córrego Grande sub-basin, differently from the former, susceptibility to linear erosion is higher in intermediate slopes (7-17%), which favors a higher concentration of surface runoff.Keywords: Erosion, Rio Vermelho Watershed, Slope, Ramp Length, Córrego Grande Sub-basin.

Orosirian I-type calc-alkaline granitoids from northern Brazil: Petrogenetic implications for evolution of the central Amazonian Craton

New petrographic, lithochemical, in situ UPb geochronological and Nd isotopes data allowed to propose a petrotectonic model for 1.90–1.88 Ga I-type calc-alkaline granitoids (Terra Preta Massif - TPM, Água Branca Suite) from the southernmost Uatumã-Anauá Domain (UAD), Ventuari-Tapajós Province (VTP), central Amazonian Craton, Brazil. The main rock facies of the TPM (1898–1885 Ma) vary from quartz monzodiorite to syenogranite, which display dominantly metaluminous to weakly peraluminous composition. A quartz diorite displaying particular petrographic features can be associated with the TPM and it does not seem to have evolved by fractional crystallization. Field and petrographic evidences, supported by trace element modeling, suggest that the quartz diorite has an origin linked to mixing between the TPM granodioritic (60 wt%) and related quartz gabbro (40 wt%) magmas. Lithochemical data show that a great petrographic variation of the TPG's main facies was not caused by fractional crystallization and point to different degrees of melting of the enriched mantle. Main facies also indicate weak positive ƐNd(t) anomalies that suggests upwelling asthenospheric mantle that provided heat to remelt the lower continental crust. The dataset of Nd isotopes and inherited zircon crystals also suggests reworking of Rhyacian granulites (French Guyana Domain-FGD, Maroni-Itacaiúnas Province) and Orosirian granulites (Anauá Complex, UAD, VTP) and assimilation of metasedimentary rocks (Cauarane Group, Central Guyana Domain, VTP), collisional granitoids (Serra Dourada Suite, UAD, VTP) and Orosirian orthogneisses (Rio Urubu Complex, CGD, VTP). Sources modeling of lithospheric mantle indicated that it is possible to generate tholeiitic mafic and I-type calc-alkaline melts, by melting of 2.15 Ga komatiitic metabasalts from FGD. A melt fraction of 28 wt% of 2.03 Ga granulites was also able to generate a liquid compatible with the main facies of the TPM. Offset of the slab breakoff in the post-collisional setting caused the asthenospheric mantle input and mixture of depleted melts (highly positive ƐNdt) with enriched melts (negative ƐNdt), resulting in ƐNd(t) values close to zero, which renders the lithospheric mantle as the main isotopic reservoir for the TPM.

­­­­­­­­­<strong>Melastomataceae in the Parque Estadual da Serra Dourada, Goiás state, Brazil</strong>

Melastomataceae is represented in the Parque Estadual da Serra Dourada by 42 taxa in 14 genera. Miconia is the most representative genus, with 18 species, followed by Tibouchina, with five, Microlicia and Pleroma with four species each, and Clidemia with two species. Acisanthera, Cambessedesia, Desmoscelis, Macairea, Pterolepis, Rhynchanthera, Siphanthera, Tococa, and Trembleya have one species each. This study provides a key to the species, descriptions, comments about morphological characters, geographical data, and the flowering and fruiting periods of each species, as well as illustrations of the species that are poorly illustrated in the literature.

Retrospective study of the situation of Brazilian countryside schools and conceptions of teachers of rural public schools in the municipality of Itapuranga, Goiás, Brazil

The aim of this study was to understand the underlying context of the countryside education according to the teachers in the municipality of Itapuranga-GO, as well as retrospective analysis of the closure of the countryside schools and the number of enrollments. Data collection included application of a questionnaire about teachers' conceptions and concepts regarding the structure, transportation, professional training and transformations in education in the school of the countryside in which they work. The survey with the teachers was carried out in August 2017 and the search for the number of enrollments and schools was carried out on the databases of QEdu and IBGE (Brazilian Institute of Geography and Statistics). Municipality of Itapuranga has two rural municipal schools, the Betel Municipal School and Serra Dourada Municipal School, containing 08 and 03 teachers, respectively. Only 09 teachers agreed to participate in this study, being 5 of the female and 4 of the male gender. The age of teachers varied from 30 to 50 years. They all have degrees in areas such as Pedagogy, Letters (English), Mathematics and/or History, and only has a complementary course in the field of countryside school, which is in Family Farming. It was verified that the management model, the contents, the projects and the training of teachers of the countryside schools of the municipality follow the same Pedagogical Political Project (PPP) of the urban schools and that there is not an effort of the state and the professionals to adapt the rural schools within established principles.

Performance of upland rice cultivars at different sowing times: an alternative for crop rotation in low altitude Cerrado region, Brazil

The adequacy of the best sowing times and the choice of rice cultivars is determinant for greater investment and return in upland rice cultivation. Thus, this study identified the best sowing time and the cultivar that expresses its yield potential, being adaptable and stable, in a low altitude Cerrado region. The study was conducted during the agricultural year 2016/17. The soil of the site is a typical clayey dystrophic Red Latosol. The experimental design was in randomized blocks, in factorial scheme with four sowing times in spring/summer season (October, November, December and February), each with eight upland rice cultivars (BRS Esmeralda, ANa 5015, ANa 6005, IPR 117, IAC 500, IAC 203, BRSGO Serra Dourada and ANa 7211) and four replicates. The following parameters were evaluated: days elapsed from emergence to flowering and harvesting, number of panicles m-2, number of filled spikelets per panicle, thousand grain weight and yield. Analyzes of adaptability and stability were performed as well as the principal components analysis. Except for the hundred grains weight, sowing times and cultivars interacted significantly for all characteristics evaluated. The cultivar BRS Esmeralda was adapted and stable to the different sowing times, being the most productive mainly when sown in October. The high yields were correlated with better grain filling, according principal components analysis.

Rice seeds vigor through image processing of seedlings

ABSTRACT: The aim of this paper was to verify the viability of digital image processing in the measurement of rice seedling and its potential use as seed vigor test. The experiment took place at the Laboratório Didático de Análise de Sementes, located in Capão do Leão (RS), using seeds of eight rice cultivars: Irga 424, Puitá Inta CL, BRS Esmeralda, SCS 116, Guri Inta CL, BRS Pampa, BRSGO Serra Dourada and Olimar. An image processing system (IPS) was used to measure length and area of shoot and root as an index of seed vigor in rice seeds. The experiment design was completely randomized with five replications. The evaluated variables were root and shoot length in graded ruler and by image, root and shoot area, and field emergence. Results obtained with the IPS were correlated with other quality tests though the Pearson tests. Determination of shoot length and leaf area of the seedlings obtained through IPS is effective for assessing the vigor of rice seeds.

Resistance in 27 Rice Cultivars to Sugarcane Borer (Lepidoptera: Crambidae).

Rice (Oryza sativa L.) is considered one of the most important crops in the world, and the sugarcane borer, Diatraea saccharalis Fabricius (Lepidoptera: Crambidae), is among the key pests damaging the crop in the Americas. The objective of this work was to identify rice genotypes as a source of resistance to D. saccharalis. Rice plants were infested in the greenhouse and subsequently evaluated for damage, larval weight and survival, and stem size. The cultivars 'Bonança', 'Caripuna', 'IR 42', 'Canela de Ferro', 'SWA Norte', 'BR IRGA 409', 'Pepita', 'Serra Dourada', 'Araguaia', 'Xingú', 'Tangará', and 'Soberana' showed antibiosis antixenosis, or both to D. saccharalis. These cultivars may be used as donor sources in the breeding program and used directly by Brazilian farmers as a component of rice-integrated pest management.

Soil management, seed treatment and soil compaction on the sowing furrows affect grain yields of upland rice genotypes

The water availability for flood irrigated rice (Oryza sativa L.) is decreasing worldwide. Therefore, developing technologies to allow growing rice in aerobic condition, such as a no-tillage system (NTS) can contribute to produce upland rice grains without yield losses and also in saving more water. The objective of this study was to determine the effect of soil management, seed treatment and compaction on the sowing furrow on grain yield of upland rice genotypes. We made two trials, one in an NTS and another using conventional tillage, CT (one plowing and two diskings). The field experiments were performed in the Central Region of Brazil in Cerrado soils. For each trial, the experimental design was a randomized block design in a factorial scheme, with three replications. The treatments consisted of a combination of 10 genotypes with 2 compaction pressures on the sowing furrow (25 kPa and 126kPa) and 2 types of seed treatment (with and without pesticide). Under CT, the seed treatment did not contribute to increase upland rice grain yields. However, under NTS the grain yield of some genotypes [BRS Esmeralda (from 723 to 1,766 kg ha-1), BRS Pepita (from 930 to 1,874 kg ha-1), AB072044 (from 523 to 1,579 kg ha-1), and AB072085 (from 632 to 1,636 kg ha-1) at 25 kPA soil compaction pressure, and Sertaneja (from 994 to 2,167 kg ha-1), BRS Pepita (from 1,161 to 2,100 kg ha-1), and AB072085 (from 958 to 2,213 kg ha-1), at 126 kPA soil compaction pressure] increased with the use of this practice. At CT the higher soil compaction pressure on the sowing furrow (from 25 kPa to 126 kPa) increased rice grain yield only when it was used seed treatment and the genotypes Serra Dourada (from 1,239 to 2,178 kg ha-1), Sertaneja (from 1,510 to 2,379 kg ha-1), and Cambara (from 1,877 to 2,831 kg ha-1). On the other hand, under NTS, increasing soil compaction pressure on the sowing furrow allowed for an increased rice grain yield of Serra Dourada (from 1,553 to 2,347 kg ha-1), Esmeralda (from 723 to 1,643 kg ha-1), AB072044 (from 523 to 2,040 kg ha-1), and Cambara (from 1,243 to 2,032 kg ha-1) without seed treatment and Sertaneja (from 1,385 to 2,167 kg ha-1) and AB072044 (from 1,579 to 2,356 kg ha-1) with seed treatment. In CT the most productive genotypes were AB062008 (2,714 kg ha-1) and BRSMG Caravera (2,479 kg ha-1), while at NTS were the genotypes: BRSGO Serra Dourada (2,118 kg ha-1), AB072047 (1,888 kg ha-1), AB062008 (1,823 kg ha-1), BRSMG Caravera (1,737 kg ha-1), Cambara (1,716 kg ha-1), AB072044 (1,625 kg ha-1), BRS Esmeralda (1,604 kg ha-1), and BRS Pepita (1,516 kg ha-1).

Seed treatment, soil compaction and nitrogen management affect upland rice

ABSTRACT Water availability for cultivation of irrigated rice (Oryza sativa L.) is decreasing worldwide. Therefore, new technologies are needed to grow rice under aerobic conditions, in order to produce rice grains without yield losses and with lower water consumption. This study aimed at determining the best combination of management options for producing upland rice. A randomized blocks design, in a factorial scheme, was used. The treatments consisted of a combination of five rice cultivars (BRS Caçula, BRS Serra Dourada, BRS Primavera, BRS Sertaneja and BRS Esmeralda) with two compaction pressures in the seed furrow (25 kPa or 126 kPa), two types of seed treatment (with or without pesticide) and two types of N management (all at sowing or all at topdressing). Applying N at sowing instead of at topdressing produced higher grain yield in the no-tillage system (NTS). Under this system, upland rice genotypes show higher grain yield with higher compaction pressure. Seed treatment with pesticide provided greater grain yield for the BRS Sertaneja, in NTS, and for all genotypes in the conventional tillage system (CTS). BRS Esmeralda, in NTS, and BRS Esmeralda and BRS Primavera, in CTS, were the most productive genotypes. Moreover, in NTS, the application of N at sowing and the compaction pressure on the seed furrow are important for increasing upland rice grain yield. In CTS, seed treatment is important to improve upland rice grain yield.

CYSTOPTERIS (CYSTOPTERIDACEAE) DEL CONO SUR Y BRASIL

A taxonomical treatment of the representatives of Cystopteris (Cystopteridaceae) occurring in Argentina, Bolivia, Brazil, Chile and Uruguay is presented. In this region, the genus is represented by three species: Cystopteris apiiformis from Argentina and Chile, C. diaphana from Argentina, Bolivia, Brazil and Uruguay, and C. ulei, endemic from Serra Dourada (Goias), Brazil. Identification keys, descriptions, comments, illustrations, the full synonymy, distribution maps, and ecological remarks for the species are presented. Four taxa: Athyrium fumarioides, C. apiiformis, C. ulei and Polypodium diaphanum are lectotypified. Two new synonyms are proposed: C. fumarioides (sensu Kunze) and C. emarginulata under C. diaphana. Cystopteris fragilis is excluded from the studied area.

Occurrence and behavior of monazite-(Ce) and xenotime-(Y) in detrital and saprolitic environments related to the Serra Dourada granite, Goiás/Tocantins State, Brazil: Potential for REE deposits

The mode of occurrence, mobility and fractionation of REE has been investigated in the geochemical context of the Serra Dourada granite, an A-type granitic body located in northern Goiás State, Brazil. Several analyses were performed to best characterize each mode of occurrence of REE, from fresh rock to its products of alteration such as the saprolite, placers and clayish horizon. In the fresh rock it was found that the REE budget is related to monazite-(Ce), xenotime-(Y), bastnäsite and allanite. Resistant monazite-(Ce) and xenotime-(Y) withstand fluvial transportation and are concentrated in placers within the massif, whereas bastnäsite and allanite do not. The alluvial sediments contain up to 0.87wt.% monazite-(Ce) and 0.46wt.% xenotime-(Y). Considering only the heavy minerals, monazite-(Ce), zircon and ilmenite represent 60–80% of the total variability, being monazite-(Ce) and xenotime-(Y) the most important REE carriers. The same minerals are also present, although in lower amounts, in the saprolite. Both qualitative and quantitative electron probe microanalyses were carried out in detrital monazite-(Ce) and xenotime-(Y) to assess their main features and composition. Monazite-(Ce) REE contents are 60wt.% in average, while REE contents in detrital xenotime-(Y) are 55wt.% in average. Low totals are ascribed to the alteration of the minerals caused by the presence of both organic and inorganic ligands present in the system. The results support the idea that REE are mobile under supergene conditions and during granite weathering, tending to be higher and more fractionated towards the products of alteration (saprolite, alluvial sediments and clayish horizon). REE2O3 contents in the fresh granite, saprolite, alluvial sediments and clayish horizon are 0.07, 0.21, 1.2 and 0.11wt.% respectively, the clayish horizon being HREE-selective. Placer deposits and the clayish horizon tend to occur in low-slope areas within the Massif, where deposition and accumulation are more favorable. The saprolite occurs preferably in high-slope areas formed in situ at the expense of the granite. The placer deposits could be exploited, but their occurrence is more restricted and local. The saprolite has the advantage of covering extensive areas widely distributed over the granite. Currently a private company, the Serra Verde Mining, posses the mining claims in the area to exploit the REE associated with the saprolite, under the model of ion-adsorption type deposits.

Stable isotope systematics and fluid inclusion studies in the Cu–Au Visconde deposit, Carajás Mineral Province, Brazil: implications for fluid source generation

The Cu–Au Visconde deposit is located in the Carajas Mineral Province (CMP), northern Brazil, near the contact between the ca. 2.76 Ga metavolcano-sedimentary rocks of the Itacaiunas Supergroup rocks and the ~3.0 Ga granitic-gneissic basement. It is hosted by mylonitized Archean rocks, mainly metadacites, the Serra Dourada granite, and gabbros/diorites, which have been successively altered by sodic, sodic-calcic-magnesian, potassic, and calcic-magnesian hydrothermal processes, producing diverse mineralogical associations (albite-scapolite; albite-actinolite-scapolite-epidote; K-feldspar-biotite; chlorite-actinolite-epidote-calcite, etc.). Chalcopyrite is the dominant ore mineral and occurs principally in breccias and veins/veinlets. The aqueous fluids responsible for the alteration/mineralization were initially hot (>460 °C) and very saline (up to 58 wt.% equivalent (equiv.) NaCl), but as the system evolved, they experienced successive dilution processes. Mineral oxygen and hydrogen isotope data show that 18O-rich (\( {\delta}^{18}{O}_{{\mathrm{H}}_2\mathrm{O}}=+4.2 \) to +9.4 ‰) fluids prevailed in the earlier alteration (including magnetitites) and reached temperatures as high as 410–355 °C. Metamorphic/formation waters, most likely derived from the Carajas Basin rocks, appear to have contributed a major component to the fluid composition, although some magmatic input cannot be discounted. In turn, the later alterations and the mineralization involved cooler (<230 °C), 18O-depleted (\( {\delta}^{18}{O}_{{\mathrm{H}}_2\mathrm{O}}=-1.3 \) to +3.7 ‰) and less saline (7–30 wt.% equiv. NaCl) fluids, indicating the influx of meteoric water. Fluid dilution and cooling might have caused abundant precipitation of sulfides, especially as breccia cement. Ore δ 34 S values (+0.5 to +3.4 ‰) suggest a magmatic source for sulfur (from sulfide dissolution in pre-existing igneous rocks). The chalcopyrite Pb–Pb ages (2.73 ± 0.15 and 2.74 ± 0.10 Ga) indicate that the Visconde mineralization is Neoarchean, rather than Paleoproterozoic as previously considered. If so, the hydrothermal processes were synchronous with the 2.75–2.73 Ga transpressive event recorded in the CMP, which is considered the most likely phenomenon that triggered the migration of highly saline fluids trapped in the Carajas Basin rocks.

Espaços educativos na perspectiva da educação integral

A proposta deste artigo é discutir o potencial educacional dos espaços educativos. A investigação percorre o cotidiano das aulas de ciências e tem como instrumento a observação participante. A amostra da pesquisa é composta de 23 alunos do sexto ano do ensino fundamental da Escola Estadual de Tempo Integral, na cidade de Goiás. Os pressupostos teóricos que direcionam a investigação estão pautados nas concepções de Anísio Teixeira, Darcy Ribeiro, Jaqueline Moll entre outros. Como parte dos resultados, evidenciou- -se que os espaços educativos, mais notadamente a nascente do rio Vermelho localizado na Serra Dourada, contribuem de forma significativa na formação integral de crianças e adolescentes.

Espaços educativos na perspectiva da educação integral

The purpose of this paper is to discuss the educational spaces as possibility of learning. The investigation discusses the routine of science classes and has as instrument the participant observation. The audience is composed by twenty-three 6th grade elementary students from the State Full-time School in the city of Goiás. The theoretical assumptions that guide the research base on the conceptions of Anísio Teixeira, Darcy Ribeiro, Jacqueline Moll and others. In the results, it became clear that the educational spaces – particularly the source of the Red River located at Serra Dourada – contribute significantly to the integral development of children and adolescents.