First in-situ measurements of plume chemistry at mount garet volcano, island of gaua (Vanuatu)

Recent volcanic gas compilations have urged the need to expand in-situ plume measurements to poorly studied, remote volcanic regions. Despite being recognized as one of the main volcanic epicenters on the planet, the Vanuatu arc remains poorly characterized for its subaerial emissions and their chemical imprints. Here, we report on the first plume chemistry data for Mount Garet, on the island of Gaua, one of the few persistent volatile emitters along the Vanuatu arc. Data were collected with a multi-component gas analyzer system (multi-GAS) during a field campaign in December 2018. The average volcanic gas chemistry is characterized by mean molar CO2 /SO2, H2 O/SO2, H2 S/SO2 and H2 /SO2 ratios of 0.87, 47.2, 0.13 and 0.01, respectively. Molar proportions in the gas plume are estimated at 95.9 ± 11.6, 1.8 ± 0.5, 2.0 ± 0.01, 0.26 ± 0.02 and 0.06 ± 0.01, for H2 O, CO2, SO2, H2 S and H2 . Using the satellite-based 10-year (2005–2015) averaged SO2 flux of ~434 t d−1 for Mt. Garet, we estimate a total volatile output of about 6482 t d−1 (CO2 ~259 t d−1; H2 O ~5758 t d−1; H2 S ~30 t d−1; H2 ~0.5 t d−1 ). This may be representative of a quiescent, yet persistent degassing period at Mt. Garet; whilst, as indicated by SO2 flux reports for the 2009–2010 unrest, emissions can be much higher during eruptive episodes. Our estimated emission rates and gas composition for Mount Garet provide insightful information on volcanic gas signatures in the northernmost part of the Vanuatu Arc Segment. The apparent CO2-poor signature of high-temperature plume degassing at Mount Garet raises questions on the nature of sediments being subducted in this region of the arc and the possible role of the slab as the source of subaerial CO2 . In order to better address the dynamics of along-arc volatile recycling, more volcanic gas surveys are needed focusing on northern Vanuatu volcanoes

Crustal controls on light noble gas isotope variability along the Andean Volcanic Arc

This study combines new noble gas data from fluid inclusions in minerals from Sabancaya, Ubinas, and El Misti (CVZ, Peru) and Villarica (South Chile, SVZ) with a revised noble gas compilation in the Andes, to identify systematic along arc variations in helium isotope compositions. We find 3He/4He ratios varying from 8.8 RA (Colombia) to 7.4 RA (Ecuador) within the NVZ, and only as high as 6.4 RA in the CVZ (RA is the atmospheric 3He/4He ratio of 1.39 × 10–6). These distinct isotope compositions cannot be explained by variable radiogenic 4He production via slab fluid transport of U and Th in the mantle wedge, since both NVZ and CVZ share similar slab sediment inputs (Th/La ≈ 0.08–0.13). Instead, the progressively more radiogenic 3He/4He signatures in Ecuador and Peru reflect 4He addition upon magma ascent/storage in the crust, this being especially thick in Peru (>70 km) and Ecuador (>50 km) relative to Colombia (∼30–45 km). The intermediate compositions in the North (8.0 RA) and South (7.9 RA) Chile, both high sediment flux margins, mostly reflect a more efficient delivery of radiogenic He in the wedge from the subducted (U-Th-rich) terrigenous sediments. Our results bring strong evidence for the major role played by crustal processes in governing noble gas compositions along continental arcs

Mafic magma feeds degassing unrest at Vulcano Island, Italy

The benign fuming activity of dormant volcanoes is punctuated by phases of escalating degassing activity that, on some occasions, ultimately prelude to eruption. However, understanding the drivers of such unrest is complicated by complex interplay between magmatic and hydrothermal processes. Some of the most comprehensively characterised degassing unrest have recently been observed at La Fossa cone on Vulcano Island, but whether or not these episodes involve new, volatile-rich ascending magma remains debated. Here, we use volcanic gas measurements, in combination with melt inclusion information, to propose that heightened sulphur dioxide flux during the intense fall 2021 La Fossa unrest is sourced by degassing of volatile-rich mafic magma. Calculations using a numerical model indicate observations are consistent with the unrest being triggered by the emplacement of ∼3·106 m3 of mafic magma at ∼4–5 km depth. Degassing of mafic magma is argued as a recurrent driver of unrest at dormant volcanoes worldwide

Prevalence of chronic kidney disease and comorbidities in isolated African descent communities (PREVRENAL): methodological design of a cohort study

Background: Chronic kidney disease (CKD) is considered a serious public health problem, both in Brazil and worldwide, with an increasing number of cases observed inrecent years. Especially, CKD has been reported to be highly prevalent in those of African descent. However, Brazil lacks data from early-stage CKD population studies, and the prevalence of CKD is unknown for both the overall and African descent populations. Hence, the present study aims to estimate the prevalence of early-stage CKD and its associated risk factors in African-Brazilians from isolated African-descent communities. Herein, the detailed methodology design of the study is described. Methods: This population-based, prospective, longitudinal, cohort study (PREVRENAL) is performed in three stages: first, clinical, nutritional, and anthropometric evaluationsmeasurements of serum and urinary markersand examinations of comorbidities were performed. Second, repeated examinations of individuals with CKD, systemic arterial hypertension, and/or diabetes mellitusimage screeningand cardiac risk assessment were performed. Third, long-term monitoring of all selected individuals will be conducted (ongoing). Using probability sampling, 1539 individuals from 32 communities were selected. CKD was defined asaglomerular filtration rate (GFR) 30 mg/day. Discussion: This study proposes to identify and monitor individuals with and without reduced GFR and high albuminuria in isolated populations of African descendants in Brazil. As there are currently no specific recommendations for detecting CKD in African descendants, four equations for estimating the GFR based on serum creatinine and cystatin C were used and will be retrospectively compared. The present report describes the characteristics of the target population, selection of individuals, and detection of a population at risk, along with the imaging, clinical, and laboratory methodologies used. The first and second stages have been concluded and the results will be published in the near future. The subsequent (third) stage is the long-term, continuous monitoring of individuals diagnosed with renal abnormalities or with CKD risk factors. The entire study population will be re-evaluated five years after the study initiation. The expectation is to obtain information about CKD evolution among this population, including the progression rate, complication development, and cardiovascular events.Research Support Foundation of Maranhao (Fundacao de Amparo a Pesquisa do Maranhao - FAPEMA)Univ Fed Maranhao, Kidney Dis Prevent Ctr, Sao Luis, MA, BrazilUniv Fed Maranhao, Dept Med 1, Sao Luis, MA, BrazilUniv Fed Maranhao, Dept Publ Hlth, Sao Luis, MA, BrazilUniv Fed Maranhao, Kidney Dis Prevent Ctr, Sao Luis, MA, BrazilUniv Fed Maranhao, Dept Physiol Sci, Sao Luis, MA, BrazilUniv Sao Paulo, Ribeirao Preto Sch Med, Dept Pathol & Radiol, Ribeirao Preto, SP, BrazilUniv Estado Rio De Janeiro, Dept Internal Med, Rio De Janeiro, RJ, BrazilUniv Fed Sao Paulo, Paulista Sch Med, Discipline Nephrol, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Paulista Sch Med, Discipline Nephrol, Sao Paulo, SP, BrazilWeb of Scienc

Diversity and ethics in trauma and acute care surgery teams: results from an international survey

Background Investigating the context of trauma and acute care surgery, the article aims at understanding the factors that can enhance some ethical aspects, namely the importance of patient consent, the perceptiveness of the ethical role of the trauma leader, and the perceived importance of ethics as an educational subject. Methods The article employs an international questionnaire promoted by the World Society of Emergency Surgery. Results Through the analysis of 402 fully filled questionnaires by surgeons from 72 different countries, the three main ethical topics are investigated through the lens of gender, membership of an academic or non-academic institution, an official trauma team, and a diverse group. In general terms, results highlight greater attention paid by surgeons belonging to academic institutions, official trauma teams, and diverse groups. Conclusions Our results underline that some organizational factors (e.g., the fact that the team belongs to a university context or is more diverse) might lead to the development of a higher sensibility on ethical matters. Embracing cultural diversity forces trauma teams to deal with different mindsets. Organizations should, therefore, consider those elements in defining their organizational procedures. Level of evidence Trauma and acute care teams work under tremendous pressure and complex circumstances, with their members needing to make ethical decisions quickly. The international survey allowed to shed light on how team assembly decisions might represent an opportunity to coordinate team member actions and increase performance

First In-Situ Measurements of Plume Chemistry at Mount Garet Volcano, Island of Gaua (Vanuatu)

Recent volcanic gas compilations have urged the need to expand in-situ plume measurements to poorly studied, remote volcanic regions. Despite being recognized as one of the main volcanic epicenters on the planet, the Vanuatu arc remains poorly characterized for its subaerial emissions and their chemical imprints. Here, we report on the first plume chemistry data for Mount Garet, on the island of Gaua, one of the few persistent volatile emitters along the Vanuatu arc. Data were collected with a multi-component gas analyzer system (multi-GAS) during a field campaign in December 2018. The average volcanic gas chemistry is characterized by mean molar CO2/SO2, H2O/SO2, H2S/SO2 and H2/SO2 ratios of 0.87, 47.2, 0.13 and 0.01, respectively. Molar proportions in the gas plume are estimated at 95.9 ± 11.6, 1.8 ± 0.5, 2.0 ± 0.01, 0.26 ± 0.02 and 0.06 ± 0.01, for H2O, CO2, SO2, H2S and H2. Using the satellite-based 10-year (2005–2015) averaged SO2 flux of ~434 t d−1 for Mt. Garet, we estimate a total volatile output of about 6482 t d−1 (CO2 ~259 t d−1; H2O ~5758 t d−1; H2S ~30 t d−1; H2 ~0.5 t d−1). This may be representative of a quiescent, yet persistent degassing period at Mt. Garet; whilst, as indicated by SO2 flux reports for the 2009–2010 unrest, emissions can be much higher during eruptive episodes. Our estimated emission rates and gas composition for Mount Garet provide insightful information on volcanic gas signatures in the northernmost part of the Vanuatu Arc Segment. The apparent CO2-poor signature of high-temperature plume degassing at Mount Garet raises questions on the nature of sediments being subducted in this region of the arc and the possible role of the slab as the source of subaerial CO2. In order to better address the dynamics of along-arc volatile recycling, more volcanic gas surveys are needed focusing on northern Vanuatu volcanoes

Influence of the satellite cells in the formation and transition of skeletal muscle fibers

Trabalho de Projeto do Mestrado Integrado em Medicina apresentado à Faculdade de MedicinaAs células satélite são células com capacidade de regenerar o tecido muscular esquelético. São activadas por um estímulo, nomeadamente uma lesão por doença ou por treino. Elas são capazes não só de manter o seu pool, como de fazer com que as células musculares recuperem de modo a que a massa muscular não seja perdida.O tecido muscular esquelético é composto fibras do tipo I e II, sendo que cada tipo é mais especializado num certo trabalho (rápido, anaeróbio; lento, aeróbio). Para além das fibras serem regeneradas com a ajuda das células satélite, que, por sua vez, aumentam em quantidade com o exercício, elas poderão converter-se para um tipo diferente de fibra consoante o tipo de treino.Este trabalho tem como objectivo rever os mecanismos biológicos das células satélite, a composição e estrutura do músculo estriado esquelético e a conversão entre fibras musculares, bem como quais os diferentes estímulos para essa conversão.Foram seleccionadas publicações escritas na língua inglesa ou portuguesa, identificadas na Pubmed e no Google Académico. Foram incluídos artigos científicos e artigos de revisão. Concluiu-se que, com o treino aeróbio, há conversão de fibras musculares do tipo II para o tipo I, enquanto que, com o treino anaeróbio, há conversão de fibras musculares do tipo I para o tipo II. Apesar de os mecanismos moleculares da acção das células satélite estar muito bem descrito, não se sabe bem qual o papel das mesmas nesta transição de fibras. Além disso, levantou-se a hipótese de as fibras não se converterem, mas sim de, com a lesão e inflamação provocada pelo treino, elas morrerem e, graças às células satélite, serem geradas fibras novas, mas de outro tipo, mais adequadas ao tipo de exercício que elas são mais frequentemente sujeitas.Satellite cells are cells capable of regenerating the skeletal muscle. They are activated by specific signals, like an injury because of disease or exercise. These cells can maintain their own pool, and also regenerate de muscular cells so that there won’t exist any loss of muscular mass. Skeletal muscle has fibers from type I and type II, and they are specialized in a certain kind of training (fast, anaerobic; slow, aerobic). Those fibers are regenerated by the satellite cells, and these last ones increase their number with training. Also, the muscular fibers can transform themselves from one type to another one. This work will review the biological mechanism of the satellite cells, the composition and structure of the skeletal muscle, the transformation between muscular fibers and all the stimulus to that transformation as well.Several publications written in english and portuguese were used to do this work, searched on Pubmed and Google Scholar. It was used scientific articles and review articles. It was concluded that, with the aerobic exercise, there is a transformation of fibers from type II to type I, and with the anaerobic exercise, there is a transformation of fibers from type I to type II. Despite of satellite cells molecular mechanisms being very well known, we don’t know their exact job in the process of fibers transformation. Also, there is an hipotesis suggesting that muscular fibers don’t transform, but, with all the injury, they die and, thanks to satellite cells, new fibers are generated, but from a different type, more specific to the type of exercise they are mostly used for

Volcanic Gas Emissions Along the Colombian Arc Segment of the Northern Volcanic Zone (CAS-NVZ): Implications for volcano monitoring and volatile budget of the Andean Volcanic Belt

Studying spatial and temporal trends in volcanic gas compositions and fluxes is crucial both to volcano monitoring and to constrain the origin and recycling efficiency of volatiles at active convergent margins. New volcanic gas compositions and volatile fluxes are here reported for Nevado del Ruiz, Galeras, and Purace, three of the most persistently degassing volcanoes located in the Colombian Arc Segment of the Northern Volcanic Zone. At Nevado del Ruiz, from 2014 to 2017, plume emissions showed an average molar CO2/S-T ratio of 3.9 +/- 1.6 (S-T is total sulfur, S). Contemporary, fumarolic chemistry at Galeras progressively shifted toward low-temperature, S-depleted fumarolic gas discharges with an average CO2/S-T ratio in excess of 10 (6.0-46.0, 2014-2017). This shift in volcanic gas compositions was accompanied by a concurrent decrease in SO2 emissions, confirmed on 21 March 2017 by high-resolution ultraviolet camera-based SO2 fluxes of similar to 2.5 kg/s (similar to 213 t/day). For comparison, SO2 emissions remained high at Nevado del Ruiz (weighted average of 8 kg/s) between 2014 and 2017, while Purace maintained rather low emission levels (<1 kg/s of SO2, CO2/SO2 approximate to 14). We here estimate carbon dioxide fluxes for Nevado del Ruiz, Galeras, and Purace of similar to 23, 30, and 1 kg/s, respectively. These, combined with recent CO2 flux estimates for Nevado del Huila of similar to 10 kg/s (similar to 860 t/day), imply that this arc segment contributes about 50% to the total subaerial CO2 budget of the Andean Volcanic Belt. Furthermore, our work highlights the northward increase in carbon-rich sediment input into the mantle wedge via slab fluids and melts that is reflected in magmatic CO2/S-T values far higher than those reported for Southern Volcanic Zone and Central Volcanic Zone volcanoes. We estimate that about 20% (similar to 1.3 Mt C/year) of the C being subducted (similar to 6.19 Mt C/year) gets resurfaced through subaerial volcanic gas emissions in Colombia (Nevado del Ruiz similar to 0.7 Mt C/year). As global volcanic volatile fluxes continue to be quantified and refined, the contribution from this arc segment should not be underestimated

First In-Situ Measurements of Plume Chemistry at Mount Garet Volcano, Island of Gaua (Vanuatu)

International audienceRecent volcanic gas compilations have urged the need to expand in-situ plume measurements to poorly studied, remote volcanic regions. Despite being recognized as one of the main volcanic epicenters on the planet, the Vanuatu arc remains poorly characterized for its subaerial emissions and their chemical imprints. Here, we report on the first plume chemistry data for Mount Garet, on the island of Gaua, one of the few persistent volatile emitters along the Vanuatu arc. Data were collected with a multi-component gas analyzer system (multi-GAS) during a field campaign in December 2018. The average volcanic gas chemistry is characterized by mean molar CO2/SO2, H2O/SO2, H2S/SO2 and H2/SO2 ratios of 0.87, 47.2, 0.13 and 0.01, respectively. Molar proportions in the gas plume are estimated at 95.9 ± 11.6, 1.8 ± 0.5, 2.0 ± 0.01, 0.26 ± 0.02 and 0.06 ± 0.01, for H2O, CO2, SO2, H2S and H2. Using the satellite-based 10-year (2005–2015) averaged SO2 flux of ~434 t d−1 for Mt. Garet, we estimate a total volatile output of about 6482 t d−1 (CO2 ~259 t d−1; H2O ~5758 t d−1; H2S ~30 t d−1; H2 ~0.5 t d−1). This may be representative of a quiescent, yet persistent degassing period at Mt. Garet; whilst, as indicated by SO2 flux reports for the 2009–2010 unrest, emissions can be much higher during eruptive episodes. Our estimated emission rates and gas composition for Mount Garet provide insightful information on volcanic gas signatures in the northernmost part of the Vanuatu Arc Segment. The apparent CO2-poor signature of high-temperature plume degassing at Mount Garet raises questions on the nature of sediments being subducted in this region of the arc and the possible role of the slab as the source of subaerial CO2. In order to better address the dynamics of along-arc volatile recycling, more volcanic gas surveys are needed focusing on northern Vanuatu volcanoes