Nota sobre a Baritina de Serrote, Estado de São Paulo

Crystals commonly tabular || c (001) occur in the place named Serrote (State of Sao Paulo) They are frequently found in the cavities of massive barite, which owes its origin probably to metasomatic processes. Occasionally the crystals exhibit distinct inclusion of microscopic needles of pyrolusite arranged in radiated orientation. Colourless when pure; yellowish and pale gree

Determinação de Indices de Zona no Sistema Hexagonal

A general graphical solution of zone index determination in the hexagonal system is herein described. Zone axis may be treated as vectors in such a manner that they could be solved into several components, according to the crystallographic axis X, Y, W , Z. These components are proportional to the searched zone indices. The vector decomposition may be performed by drawing normals to the crystallographic axis from any given point P of the vector. In such way, the computed zone indices will satisfy the condition u+v +ɯ=

Aplicações da Trigonometria Esférica em problemas da Simetria Cristalográfica

The present article deals with the application of elementary spherical trigonometry to solution of symmetry problems. The main purpose of the article is to point out symmetry axis associations, and to show the possibilities and impossibilities of several associations, revealed through spherical trigonometric relations. The following axis associations have been a matter of study : a ) 6 + 6; b ) 4 + 4; c ) 2 + 2; d ) 6 + 3; e ) 6 + 4; f ) 6 + 2; g ) 4 + 3. For solution of all the proposed problem sonly one trigonometric formula has been used: cos a = cos b cos c + sen b sen c cos A which is applicable to scalene triangle

Estudo cristaloquimico de rutílios inclusos em diamantes naturais

Rutile has been identified as syngenetic inclusion in detritic diamonds from Garças River (Mato Grosso State), and Caiapó River (Goiás State), Brazil. The inclusions, which are brown colored and prismatic in habit, have dimensions approximately 1 mm along the crystallographic c axis. The unit cell dimensions are a o = 4,59 Å and c o = 2,95 Å, measured in precession photographs. Microprobe analyses show that the rutile is almost depleted from chemical impurities; besides TiO2 whose content ranges around 99,7%, rutile contains less than 0,4% of Si, Al, Cr, Fe, Mg, Ca and Mn. Presumably, the inclusions, as well as their diamond hosts crystallized in an eclogitic environment, similar to the eclogite xenoliths found in kimberlites.Inclusões singenéticas de rutílio foram identificadas em diamantes aluvionares dos rios das Garças (Mato Grosso) e Caiapó (Goiás). As referidas inclusões constituem cristais prismáticos terminados, acentuadamente alongados na direção do eixo cristalográfico c; apresentam coloração castanha intensa e dimensões próximas de 1 mm na direção de maior alongamento dos cristais. Observações adicionais efetuadas por meio do microscópio eletrônico de varredura revelaram microestruturas concordantes com a simetria pontual do rutílio. As dimensões da cela unitária determinadas pelo método de precessão são: a o = 4,59 Å e c o = 2,95 Å. Os dados de composição química, obtidos com o auxílio da microssonda eletrônica, indicam que as inclusões de rutílios são próximas de estequimetria química e praticamente isentas de impurezas. Além do TiO2 , cuja média nas duas amostras analisadas é de 99,7%, os demais óxidos ocorrem em proporções menores de 0,4%. O teor baixo de Cr2O3 (< 0,2%) sugere que as inclusões de rutílio, e conseqüentemente os diamantes hospedeiros, cristalizaram-se a partir de uma assembléia mineralógica de natureza eclogítica

Arsenopirita de Juca Vieira, Caeté, Minas Gerais, Brasil

Well-formed arsenopyrite crystals occur included into sericite talc schists, associated with pyrite. The arsenopyrite, commonly twinned after (101) and (110) , shows the following crystallographic forms: (110) , (014 ) and more rarely (001) and (011) . The arsenopyrite is frequently fractured, exhibiting inclusions of euhedral pyrite crystals, which probably have been formed through replacement by penetration of forming solutions into the arsenopyrite small crack

Salivary exRNA biomarkers to detect gingivitis and monitor disease regression

AimThis study tests the hypothesis that salivary extracellular RNA (exRNA) biomarkers can be developed for gingivitis detection and monitoring disease regression.Materials and MethodsSalivary exRNA biomarker candidates were developed from a total of 100 gingivitis and nonâ gingivitis individuals using Affymetrix’s expression microarrays. The top 10 differentially expressed exRNAs were tested in a clinical cohort to determine whether the discovered salivary exRNA markers for gingivitis were associated with clinical gingivitis and disease regression. For this purpose, unstimulated saliva was collected from 30 randomly selected gingivitis subjects, the gingival and plaque indexes scores were taken at baseline, 3 and 6 weeks and salivary exRNAs were assayed by means of reverse transcription quantitative polymerase chain reaction.ResultsEight salivary exRNA biomarkers developed for gingivitis were statistically significantly changed over time, consistent with disease regression. A panel of four salivary exRNAs [SPRR1A, lncâ TET3â 2:1, FAM25A, CRCT1] can detect gingivitis with a clinical performance of 0.91 area under the curve, with 71% sensitivity and 100% specificity.ConclusionsThe clinical values of the developed salivary exRNA biomarkers are associated with gingivitis regression. They offer strong potential to be advanced for definitive validation and clinical laboratory development test.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144647/1/jcpe12930.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144647/2/jcpe12930_am.pd

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Agenesia e lipoma de corpo caloso: relato de caso

The agenesis and lipoma of the corpus callosum is a very rare association. We report the case of a 18-years old woman with rare epileptic seizures since the age of 6 years, normal neurological examination, as well as normal electroencephalogram. The brain computed tomography scanning and the magnetic resonance showed the lipoma and the agenesis of the corpus callosum.A agenesia e lipoma do corpo caloso é uma associação muito rara. Relatamos o caso de uma paciente de 18 anos com raras crises epilépticas desde os 6 anos de idade, exame neurológico normal, assim como eletrencefalograma normal. A tomografia computadorizada de crânio e a ressonância magnética mostraram o lipoma e a agenesia de corpo caloso.Escola Paulista de MedicinaUNIFESP, EPMSciEL

Carbon uptake by mature Amazon forests has mitigated Amazon nations' carbon emissions

Background: Several independent lines of evidence suggest that Amazon forests have provided a significant carbon sink service, and also that the Amazon carbon sink in intact, mature forests may now be threatened as a result of different processes. There has however been no work done to quantify non-land-use-change forest carbon fluxes on a national basis within Amazonia, or to place these national fluxes and their possible changes in the context of the major anthropogenic carbon fluxes in the region. Here we present a first attempt to interpret results from groundbased monitoring of mature forest carbon fluxes in a biogeographically, politically, and temporally differentiated way. Specifically, using results from a large long-term network of forest plots, we estimate the Amazon biomass carbon balance over the last three decades for the different regions and nine nations of Amazonia, and evaluate the magnitude and trajectory of these differentiated balances in relation to major national anthropogenic carbon emissions. Results: The sink of carbon into mature forests has been remarkably geographically ubiquitous across Amazonia, being substantial and persistent in each of the five biogeographic regions within Amazonia. Between 1980 and 2010, it has more than mitigated the fossil fuel emissions of every single national economy, except that of Venezuela. For most nations (Bolivia, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname) the sink has probably additionally mitigated all anthropogenic carbon emissions due to Amazon deforestation and other land use change. While the sink has weakened in some regions since 2000, our analysis suggests that Amazon nations which are able to conserve large areas of natural and semi-natural landscape still contribute globally-significant carbon sequestration. Conclusions: Mature forests across all of Amazonia have contributed significantly to mitigating climate change for decades. Yet Amazon nations have not directly benefited from providing this global scale ecosystem service. We suggest that better monitoring and reporting of the carbon fluxes within mature forests, and understanding the drivers of changes in their balance, must become national, as well as international, priorities

Evolutionary Heritage Influences Amazon Tree Ecology

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change