Química mineral e geotermobarometria de rochas neoproterozoicas do nordeste do Cinturão Dom Feliciano, RS

O nordeste do Cinturão Dom Feliciano compreende rochas gnáissicas tonalíticas de afinidade cálcico-alcalina médio-K, de fácies anfibolito, e rochas graníticas póstranscorrentes de afinidade cálcico-alcalina alto-K e alcalina. Com o objetivo de obter dados a respeito das condições de formação destas rochas, métodos geotermobarométricos com base na química mineral e de rocha total foram aplicados. A química mineral dos anfibólios das rochas gnáissicas (Fe-hornblenda a Fetschermakita) registrou uma mudança nas condições de pressão que foi interpretada como tendo um núcleo ígneo, com temperaturas, pressões e profundidades, respectivamente, de 710 a 760 °C, 3,4 a 3,9 kbar e 12 a 14 km; e uma borda metamórfica de 690 a 760 °C, 4,8 a 7,7 kbar e 18 a 28 km. A química mineral dos anfibólios dos granitos (Mg-hornblenda) registrou temperaturas de 659 a 759 e pressões de 3,2 a 5,0 kbar, com profundidades de 11 a 18 km. As temperaturas obtidas com base no teor de Zr na titanita registraram eventos entre 607 a 881 °C, que foram interpretados, em conjunto com observações petrográficas, como tendo tanto uma origem magmática (700 – 881 °C), quanto pós-magmática (<700 °C), ambas com características químicas distintas.The northeast of the Dom Feliciano Belt comprises post-transcending granitic rocks of high K-alkaline and alkaline affinity, and tonalitic gneissic rocks of amphibolite-calciumalkaline affinity. In order to obtain data regarding the formation conditions of these rocks, geothermobarometric methods based on mineral chemistry and bulk rock geochemistry were applied. The mineral chemistry of the amphiboles of the gneiss rocks (Fe-hornblende to Fe-tschermakite) registered a change in pressure conditions that were interpreted as having an igneous core, with temperatures, pressures and depths, respectively, from 710 to 760 ° C, 3,4 to 3.9 kbar and 12 to 14 km; and a metamorphic rim of 690 to 760 ° C, 4.8 to 7.7 kbar and 18 to 28 km. The mineral chemistry of granite amphiboles (Mg-hornblende) recorded temperatures from 659 to 759 and pressures from 3.2 to 5.0 kbar, with depths from 11 to 18 km. The temperatures obtained based on the Zr content in titanite registered events between 607 to 881 ° C, which were interpreted, together with petrographic observations, as having both a magmatic (700 - 881 ° C) and post-magmatic origin (<700 ° C), both with different chemical characteristics

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Leucita - Nefelina - Diopsídio a 4 GPa no estudo da estabilidade das fases potássicas no manto superior

O diagrama de fase ternário Lc(leucita)-Ne(nefelina)-Di(diopsídio) pode ser utilizado para responder questões sobre o comportamento dos elementos alcalinos (Na e K) durante a evolução da Terra no seu período de acresção planetária, além de acrescentar informações importantes sobre a gênese de rochas alcalinas potássicas e sódicas. A sua construção pode ser realizada através de técnicas de petrologia experimental. O potássio, um elemento litófilo, móvel, incompatível e volátil para as temperaturas de acresção planetária tende a se concentrar na parte silicática do Planeta ou ser volatizado durante a acresção do planeta. Estudos mais recentes, entretanto, sugerem que ele possa ter sido aprisionado em porções mais profundas do manto durante esta fase de acreção. A finalidade deste estudo foi investigar quais as fases estáveis e em equilíbrio com um líquido, e suas composições no diagrama Lc-Ne-Di em temperaturas de até 1400°C e pressão de 4 GPa. Estudos experimentais neste diagrama foram realizados no Laboratório de Altas Pressões e Materiais Avançados (LAPMA) em prensa de 1000 tonf com câmaras de perfil toroidal a pressão de 4 GPa. O material inicial foi produzido a partir de óxidos e carbonatos em proporções estequiométricas e a célula de reação utilizada, composta por cápsula de platina, pirofilita, nitreto de boro hexagonal (h-BN) e grafite, e gaxeta de material carbonático. As fases cristalizadas obtidas nos experimentos incluem Cpx, Ks, Kf e Ne. O maior conteúdo de potássio (K2O) encontrado no Cpx foi de 2,02%peso, cujo coeficiente de partição foi de 0,34. O maior conteúdo de K2O no Cpx foi relacionado positivamente com a quantidade de Na2O e Al2O3. Essas quantidades de K encontradas no Cpx evidenciam uma possibilidade de existência de reservatório de K no manto.The ternary phase diagram Lc (leucite) - Ne (nepheline) - Di (diopside) can be used to answer questions about the behavior of alkaline elements (Na and K) during the evolution of Earth in its period of planetary accretion, and add important information about the genesis of potassic and sodic alkaline rocks. Its construction can be accomplished through techniques of experimental petrology. Potassium, an element litófilo, mobile, incompatible and volatile at temperatures of planetary accretion tends to be concentrated in the silicate Earth or be volatilized during the accretion of the planet. More recent studies, however, suggest that he may have been trapped in the deeper portions of the mantle during this phase of accretion. The purpose of this study was to investigate which phases in stable equilibrium with a liquid, and their compositions in the diagram Lc-Ne-Di at temperatures up to 1400°C and pressure of 4 GPa. in this diagram experimental studies were performed at the Laboratory of High pressures and Advanced Materials (LAPMA) in press 1000 tonf profile toroidal chamber with a pressure of 4 GPa. The starting material was produced from oxides and carbonates in stoichiometric proportions and the reaction cell used consisting of a platinum dish and pyrophyllite , hexagonal boron nitride (h-BN) and graphite, and gasket carbonate material. The crystallized phases obtained in the experiments include Cpx, Ks, Kf and Ne. The highest content of potassium (K2O) Cpx was found in 2.02 wt%, whose partition coefficient was 0.34. The highest content of K2O in Cpx was positively related to the amount of Na2O and Al2O3. These amounts of K found in Cpx show a possibility of K in the mantle reservoir

Leucita - Nefelina - Diopsídio a 4 GPa no estudo da estabilidade das fases potássicas no manto superior

O diagrama de fase ternário Lc(leucita)-Ne(nefelina)-Di(diopsídio) pode ser utilizado para responder questões sobre o comportamento dos elementos alcalinos (Na e K) durante a evolução da Terra no seu período de acresção planetária, além de acrescentar informações importantes sobre a gênese de rochas alcalinas potássicas e sódicas. A sua construção pode ser realizada através de técnicas de petrologia experimental. O potássio, um elemento litófilo, móvel, incompatível e volátil para as temperaturas de acresção planetária tende a se concentrar na parte silicática do Planeta ou ser volatizado durante a acresção do planeta. Estudos mais recentes, entretanto, sugerem que ele possa ter sido aprisionado em porções mais profundas do manto durante esta fase de acreção. A finalidade deste estudo foi investigar quais as fases estáveis e em equilíbrio com um líquido, e suas composições no diagrama Lc-Ne-Di em temperaturas de até 1400°C e pressão de 4 GPa. Estudos experimentais neste diagrama foram realizados no Laboratório de Altas Pressões e Materiais Avançados (LAPMA) em prensa de 1000 tonf com câmaras de perfil toroidal a pressão de 4 GPa. O material inicial foi produzido a partir de óxidos e carbonatos em proporções estequiométricas e a célula de reação utilizada, composta por cápsula de platina, pirofilita, nitreto de boro hexagonal (h-BN) e grafite, e gaxeta de material carbonático. As fases cristalizadas obtidas nos experimentos incluem Cpx, Ks, Kf e Ne. O maior conteúdo de potássio (K2O) encontrado no Cpx foi de 2,02%peso, cujo coeficiente de partição foi de 0,34. O maior conteúdo de K2O no Cpx foi relacionado positivamente com a quantidade de Na2O e Al2O3. Essas quantidades de K encontradas no Cpx evidenciam uma possibilidade de existência de reservatório de K no manto.The ternary phase diagram Lc (leucite) - Ne (nepheline) - Di (diopside) can be used to answer questions about the behavior of alkaline elements (Na and K) during the evolution of Earth in its period of planetary accretion, and add important information about the genesis of potassic and sodic alkaline rocks. Its construction can be accomplished through techniques of experimental petrology. Potassium, an element litófilo, mobile, incompatible and volatile at temperatures of planetary accretion tends to be concentrated in the silicate Earth or be volatilized during the accretion of the planet. More recent studies, however, suggest that he may have been trapped in the deeper portions of the mantle during this phase of accretion. The purpose of this study was to investigate which phases in stable equilibrium with a liquid, and their compositions in the diagram Lc-Ne-Di at temperatures up to 1400°C and pressure of 4 GPa. in this diagram experimental studies were performed at the Laboratory of High pressures and Advanced Materials (LAPMA) in press 1000 tonf profile toroidal chamber with a pressure of 4 GPa. The starting material was produced from oxides and carbonates in stoichiometric proportions and the reaction cell used consisting of a platinum dish and pyrophyllite , hexagonal boron nitride (h-BN) and graphite, and gasket carbonate material. The crystallized phases obtained in the experiments include Cpx, Ks, Kf and Ne. The highest content of potassium (K2O) Cpx was found in 2.02 wt%, whose partition coefficient was 0.34. The highest content of K2O in Cpx was positively related to the amount of Na2O and Al2O3. These amounts of K found in Cpx show a possibility of K in the mantle reservoir