Seafloor massive sulfides from mid-ocean ridges: Exploring the causes of their geochemical variability with multivariate analysis

The neovolcanic zones of mid-ocean ridges are host to seawater-derived hydrothermal systems forming seafloor massive sulfide (SMS) deposits. These deposits have high concentrations of base metals and potentially economic enrichment of a wide range of trace elements. The factors controlling this enrichment are currently poorly understood. We have investigated the main factors controlling SMS compositional variability through robust principal component analysis and robust factor analysis of published and newly obtained bulk geochemical data for samples collected from SMS deposits worldwide. We found that a large part of the observed variability is produced by a combination of three independent factors, which are interpreted to reflect (in order of importance): (1) the temperature of deposition, (2) the ridge spreading rate, and (3) zone refining. The first and the third factors are mostly related to processes operating near the seafloor, such as conductive cooling, mixing of the hydrothermal fluids with seawater and metal remobilization, and determine the relative proportions of the main minerals and, thus, of Cu and Zn (Co, Se, Sb, Pb). The ridge spreading rate influences the structure of the oceanic lithosphere, which exerts a major control on the length and depth of the hydrothermal convection cell and on the rock-to-water ratios in the reaction zone, which in turn control the behavior of the precious metals Au and Ag and elements including Ni (Mo, Se). Despite the obvious role of substrate rocks as metal sources, their composition (specifically mafic vs. ultramafic) does not emerge as a statistically significant independent factor

The issues of implementation of simulation-simulation module in the curriculum of the virtual clinic emergency conditions

The aim of this work was the optimization of the learning process diagnostic and treatment interventions at emergencies in clinic of internal diseases students of 6 course of medical faculty. The object of the study was the simulation of interregional certification centre NSMU, the subject of the study — simulation clinic emergency conditions, emergency medicine. Formulated the hypothesis: based on the mining simulation equipment ("Apollo" and ESC) practical skills in physical name, instrumental examination of the patient and treatment to enhance efficiency and quality assist with emergency status, successful completion of an accreditation graduates with developed check sheet with the sequence of actions in providing medical emergency care to the patient with hypertension issues for the input test control of level of knowledge, questionnaire evaluation of satisfaction of students, list of questions for final test control of knowledge level (Moodle), practical tasks and creation of electronic clinical tasks with the incremental algorithm.Целью работы явилась оптимизация процесса обучения диагностическим и лечебным мероприятиям при неотложных состояниях в клинике внутренних болезней студентов 6 курса лечебного факультета. Объектом исследования стал межрегиональный симуляционно-аттестационный центр НГМУ, предметом исследования — симуляционная клиника неотложных состояний, отделение неотложной терапии. Была сформулирована гипотеза: на основе отработки на симуляционном оборудовании («Аполло» и ESC) практических навыков по физикальному, инструментальному обследованию пациента и лечению, повысить эффективность, качество оказания помощи при неотложном состоянии, успешное прохождение аккредитации выпускниками с помощью разработанных: чек-листа с алгоритмом действий при оказании медицинской неотложной помощи больному с артериальной гипертензией, вопросов для входного тестового контроля, уровня знаний анкеты оценки удовлетворенности обучающихся, перечня вопросов для итогового тестового контроля уровня знаний (система Moodle), ситуационных заданий, а также создания клинических электронных задач с пошаговым алгоритмо

Hydrogen and chlorine abundances in the Kimberley formation of Gale crater measured by the DAN instrument on board the Mars Science Laboratory Curiosity rover

The Dynamic Albedo of Neutron (DAN) instrument on board the Mars Science Laboratory Curiosity rover acquired a series of measurements as part of an observational campaign of the Kimberley area in Gale crater. These observations were planned to assess the variability of bulk hydrogen and neutron‐absorbing elements, characterized as chlorine‐equivalent concentration, in the geologic members of the Kimberley formation and in surface materials exposed throughout the area. During the traverse of the Kimberley area, Curiosity drove primarily over the “Smooth Hummocky” unit, a unit composed primarily of sand and loose rocks, with occasional stops at bedrock of the Kimberley formation. During the Kimberley campaign, DAN detected ranges of water equivalent hydrogen (WEH) and chlorine‐equivalent concentrations of 1.5–2.5 wt % and 0.6–2 wt %, respectively. Results show that as the traverse progressed, DAN observed an overall decrease in both WEH and chlorine‐equivalent concentration measured over the sand and loose rocks of the Smooth Hummocky unit. DAN measurements of WEH and chlorine‐equivalent concentrations in the well‐exposed sedimentary bedrock of the Kimberley formation show fluctuations with stratigraphic position. The Kimberley campaign also provided an opportunity to compare measurements from DAN with those from the Sample Analysis at Mars (SAM) and the Alpha‐Particle X‐ray Spectrometer (APXS) instruments. DAN measurements obtained near the Windjana drill location show a WEH concentration of ~1.5 wt %, consistent with the concentration of low‐temperature absorbed water measured by SAM for the Windjana drill sample. A comparison between DAN chlorine‐equivalent concentrations measured throughout the Kimberley area and APXS observations of corresponding local surface targets and drill fines shows general agreement between the two instruments

Hydrogen and chlorine abundances in the Kimberley formation of Gale crater measured by the DAN instrument on board the Mars Science Laboratory Curiosity rover

The Dynamic Albedo of Neutron (DAN) instrument on board the Mars Science Laboratory Curiosity rover acquired a series of measurements as part of an observational campaign of the Kimberley area in Gale crater. These observations were planned to assess the variability of bulk hydrogen and neutron‐absorbing elements, characterized as chlorine‐equivalent concentration, in the geologic members of the Kimberley formation and in surface materials exposed throughout the area. During the traverse of the Kimberley area, Curiosity drove primarily over the “Smooth Hummocky” unit, a unit composed primarily of sand and loose rocks, with occasional stops at bedrock of the Kimberley formation. During the Kimberley campaign, DAN detected ranges of water equivalent hydrogen (WEH) and chlorine‐equivalent concentrations of 1.5–2.5 wt % and 0.6–2 wt %, respectively. Results show that as the traverse progressed, DAN observed an overall decrease in both WEH and chlorine‐equivalent concentration measured over the sand and loose rocks of the Smooth Hummocky unit. DAN measurements of WEH and chlorine‐equivalent concentrations in the well‐exposed sedimentary bedrock of the Kimberley formation show fluctuations with stratigraphic position. The Kimberley campaign also provided an opportunity to compare measurements from DAN with those from the Sample Analysis at Mars (SAM) and the Alpha‐Particle X‐ray Spectrometer (APXS) instruments. DAN measurements obtained near the Windjana drill location show a WEH concentration of ~1.5 wt %, consistent with the concentration of low‐temperature absorbed water measured by SAM for the Windjana drill sample. A comparison between DAN chlorine‐equivalent concentrations measured throughout the Kimberley area and APXS observations of corresponding local surface targets and drill fines shows general agreement between the two instruments

Using the Schaefer production model for assessment of the Barents Sea Greenland halibut

In 2010 commercial fishing of Greenland halibut in the Barents Sea was reopened. But due to poor fitting of the previous model to input data, management of fishery is currently being performed using the survey trends. In this paper, the calculations of the Barents Sea halibut stock based on the Schaefer production model have been presented and some conclusions about the applicability of this model have been mad