Water and Chlorine in the Martian Subsurface Along the Traverse of NASA's Curiosity Rover: 1. DAN Measurement Profiles Along the Traverse.

This paper presents estimates of the water and chlorine contents in the subsurface of Gale crater based on the measurements by the Dynamic Albedo of Neutrons (DAN) instrument onboard the NASA Curiosity rover. It is Part 1 of a two-paper series. Data derived both from DAN active and passive measurements are presented in discrete surface areas (pixels) assuming a homogeneous distribution of water within the DAN sensing depth (60 cm) along the traverse of the rover. It is shown that the content of hydrogen, reported as Water Equivalent Hydrogen, varies between almost zero and a maximum of (6.1 ± 0.7) wt.%. The content of absorption equivalent chlorine varies between almost zero and (2.6 ± 0.2) wt.%. Such variations are thought to be related to the different geological processes and environmental conditions present in the strata along the traverse during the evolutionary history of Gale crater. The second paper (Part 2) studies particular properties of water and abundances of neutron absorbing elements at distinct geological regions, that the rover crossed on its way.

Observations of neutron radiation environment during Odyssey cruise to Mars.

In April 2001, Mars Odyssey spacecraft with the High Energy Neutron Detector (HEND) onboard was launched to Mars. HEND/Odyssey was switched on measurement mode for most of transit to Mars to monitor variations of spacecraft background and solar activity. Although HEND/Odyssey was originally designed to measure Martian neutron albedo and to search for Martian subsurface water/water ice, its measurements during cruise phase to Mars are applicable to evaluate spacecraft ambient radiation background. The biological impact of the neutron component of this radiation background should be understood, as it must be taken into account in planning future human missions to Mars. We have modeled the spacecraft neutron spectral density and compared it with HEND measurements to estimate neutron dose equivalent rates during Odyssey cruise phase, which occurred during the maximum period of solar cycle 23. We find that the Odyssey ambient neutron environment during May - September 2001 yields 10.6 ± 2.0 µSv per day in the energy range from 0 to 15 MeV, and about 29 µSv per day when extrapolated to the 0-1000 MeV energy range during solar quiet time (intervals without Solar Particle Events, SPEs). We have also extrapolated HEND/Odyssey measurements to different periods of solar cycle and find that during solar minimum (maximum of GCR flux), the neutron dose equivalent rate during cruise to Mars could be as high as 52 µSv per day with the same shielding. These values are in good agreement with results reported for a similar measurement made with an instrument aboard the Mars Science Laboratory during its cruise to Mars in 2011-2012.

A bright γ-ray flare interpreted as a giant magnetar flare in NGC 253.

Soft γ-ray repeaters exhibit bursting emission in hard X-rays and soft γ-rays. During the active phase, they emit random short (milliseconds to several seconds long), hard-X-ray bursts, with peak luminosities1 of 1036 to 1043 erg per second. Occasionally, a giant flare with an energy of around 1044 to 1046 erg is emitted2. These phenomena are thought to arise from neutron stars with extremely high magnetic fields (1014 to 1015 gauss), called magnetars1,3,4. A portion of the second-long initial pulse of a giant flare in some respects mimics short γ-ray bursts5,6, which have recently been identified as resulting from the merger of two neutron stars accompanied by gravitational-wave emission7. Two γ-ray bursts, GRB 051103 and GRB 070201, have been associated with giant flares2,8-11. Here we report observations of the γ-ray burst GRB 200415A, which we localized to a 20-square-arcmin region of the starburst galaxy NGC 253, located about 3.5 million parsecs away. The burst had a sharp, millisecond-scale hard spectrum in the initial pulse, which was followed by steady fading and softening over 0.2 seconds. The energy released (roughly 1.3 × 1046 erg) is similar to that of the superflare5,12,13 from the Galactic soft γ-ray repeater SGR 1806-20 (roughly 2.3 × 1046 erg). We argue that GRB 200415A is a giant flare from a magnetar in NGC 253.

Association of Arterial Hypertension with Hepatobiliary Pathology: The Occurrence of Comorbidity and Features of Metabolic Processes.

Comorbidity of hypertension and hepatobiliary pathology has negative medical and social consequences, including an increase in the indicators of hospital admissions, disability and mortality. OBJECTIVE: The aim was to study the occurrence of hypertension combined with hepatobiliary diseases depending on social status, gender and age in 2003-2017 and their influence on indicators of metabolic processes in patients with a therapeutic profile. METHODS: A cross-sectional study using the inpatients' medical record database of the clinic of Federal Research Centre for Basic and Translational Medicine (Novosibirsk, Russia), which collects demographics, diagnoses (using ICD-10 codes), procedures and examinations of all inpatients from 2003-2017 was conducted. The incidence of comorbidity of hypertension and hepatobiliary pathology depending on age, gender and social status, based on the analysis of 13496 medical records was examined. A comparative analysis of biochemical parameters characterizing the main types of metabolism (lipid, protein, carbohydrate and purine) was carried out in 3 groups of patients: with hypertension; with hepatobiliary pathology, and with a combined pathology. RESULTS: During the years 2003-2005, there was the greatest frequency of this comorbidity in workers, in women, in the age group 60 years and older. In 2009-2017, the highest incidence was observed in the male administrative staff. In patients with this comorbidity, more pronounced changes in carbohydrate, protein, lipid and purine metabolism were found in comparison with groups of patients with isolated diseases. CONCLUSION: The results highlight the need to improve the system of prevention and treatment of comorbidity taking into account sex, age, occupation and features of metabolism.

The ADRON-RM Instrument Onboard the ExoMars Rover.

This overview presents the physical principles, design, measurement capabilities, and summary of planned operations of the autonomous detector of radiation of neutrons onboard rover at Mars (ADRON-RM) on the surface of Mars. ADRON-RM is a Russian project selected for the joint European Space Agency-Roscosmos ExoMars 2020 landing mission. A compact passive neutron spectrometer, ADRON-RM, was designed to study the abundance and distribution of water and neutron absorption elements (such as Cl, Fe, and others) in the martian subsurface along the path of the ExoMars rover. Key Words: Mars exploration-Surface-Neutron Spectroscopy-Water. Astrobiology 17, 585-594.

A comparative study of LaBr3(Ce(3+)) and CeBr3 based gamma-ray spectrometers for planetary remote sensing applications.

The recent availability of large volume cerium bromide crystals raises the possibility of substantially improving gamma-ray spectrometer limiting flux sensitivities over current systems based on the lanthanum tri-halides, e.g., lanthanum bromide and lanthanum chloride, especially for remote sensing, low-level counting applications or any type of measurement characterized by poor signal to noise ratios. The Russian Space Research Institute has developed and manufactured a highly sensitive gamma-ray spectrometer for remote sensing observations of the planet Mercury from the Mercury Polar Orbiter (MPO), which forms part of ESA's BepiColombo mission. The Flight Model (FM) gamma-ray spectrometer is based on a 3-in. single crystal of LaBr3(Ce(3+)) produced in a separate crystal development programme specifically for this mission. During the spectrometers development, manufacturing, and qualification phases, large crystals of CeBr3 became available in a subsequent phase of the same crystal development programme. Consequently, the Flight Spare Model (FSM) gamma-ray spectrometer was retrofitted with a 3-in. CeBr3 crystal and qualified for space. Except for the crystals, the two systems are essentially identical. In this paper, we report on a comparative assessment of the two systems, in terms of their respective spectral properties, as well as their suitability for use in planetary mission with respect to radiation tolerance and their propensity for activation. We also contrast their performance with a Ge detector representative of that flown on MESSENGER and show that: (a) both LaBr3(Ce(3+)) and CeBr3 provide superior detection systems over HPGe in the context of minimally resourced spacecraft and (b) CeBr3 is a more attractive system than LaBr3(Ce(3+)) in terms of sensitivities at lower gamma fluxes. Based on the tests, the FM has now been replaced by the FSM on the BepiColombo spacecraft. Thus, CeBr3 now forms the central gamma-ray detection element on the MPO spacecraft.

[Features of polymorbidity in cardiac and gastroenterologic patients from a therapeutic clinic].

AIM: To examine the incidence of polymorbidity (PM) and changes in its rates in 2003 to 2011 in cardiac and gastroenterologic patients living in the Novosibirsk Region and the Republic of Sakha (Yakutia) in accordance with gender, occupation, and residence. SUBJECTS AND METHODS: The dynamics of PM rates was analyzed in 13 496 patients who had been examined and treated at the Cardiology and Gastroenterology Departments, Therapeutic Clinic, Research Institute of Experimental and Clinical Medicine (Novosibirsk), 2003-2011. The study used an archival research method and a statistical analysis of all nosological entities, groups, and classes in ICD-10, regardless of whether the diagnosis was primary or concurrent. RESULTS: There was an increase in PM rates among the therapeutic clinic's patients of regardless of their gender and occupation. There were gender differences in the incidence of PM: its higher rates were noted in the women than those in the men among both the residents of the Novosibirsk Region and those of the Republic of Sakha (Yakutia). More significantly higher PM rates were registered in the male inhabitants of the Novosibirsk Region. There were also regional differences in the incidence of PM: its rates proved to be higher in the patients in the Republic of Sakha (Yakutia) than in those in the Novosibirsk Region in 2003-2007. At the same time, the growth rates for PM were more marked in the patients in the Novosibirsk region than in those in the Republic of Sakha (Yakutia); these differences levelled off in subsequent years. CONCLUSION: The findings indicate a pronounced increase in the incidence of PM in cardiac and gastroentorologic patients and determine a need to keep in mind the influence of gender, social, and regional factors on its development in order to create and improve a primary and secondary prevention, diagnosis and treatment system.

Moonshine: Diurnally varying hydration through natural distillation on the Moon, detected by the Lunar Exploration Neutron Detector (LEND).

The Lunar Exploration Neutron Detector (LEND), on the polar-orbiting Lunar Reconnaissance Orbiter (LRO) spacecraft, has detected suppression in the Moon's naturally-occurring epithermal neutron leakage flux that is consistent with the presence of diurnally varying quantities of hydrogen in the regolith near the equator. Peak hydrogen concentration (neutron flux suppression) is on the dayside of the dawn terminator and diminishes through the dawn-to-noon sector. The minimum concentration of hydrogen is in the late afternoon and dusk sector. The chemical form of hydrogen is not determinable from these measurements, but other remote sensing methods and anticipated elemental availability suggest water molecules or hydroxyl ions. Signal-to-noise ratio at maximum contrast is 5.6σ in each of two detector systems. Volatiles are deduced to collect in or on the cold nightside surface and distill out of the regolith after dawn as rotation exposes the surface to sunlight. Liberated volatiles migrate away from the warm subsolar region toward the nearby cold nightside surface beyond the terminator, resulting in maximum concentration at the dawn terminator. The peak concentration within the upper ~1 m of regolith is estimated to be 0.0125 ± 0.0022 weight-percent water-equivalent hydrogen (wt% WEH) at dawn, yielding an accumulation of 190 ± 30 ml recoverable water per square meter of regolith at each dawn. Volatile transport over the lunar surface in opposition to the Moon's rotation exposes molecules to solar ultraviolet radiation. The short lifetime against photolysis and permanent loss of hydrogen from the Moon requires a resupply rate that greatly exceeds anticipated delivery of hydrogen by solar wind implantation or by meteoroid impacts, suggesting that the surface inventory must be continually resupplied by release from a deep volatile inventory in the Moon. The natural distillation of water from the regolith by sunlight and its capture on the cold night surface may provide energy-efficient access to volatiles for in situ resource utilization (ISRU) by direct capture before volatiles can enter the surface, eliminating the need to actively mine regolith for volatile resource recovery.

[Combination of arterial hypertension and type 2 diabetes mellitus with obesity].

The aim of the study was to elucidate dynamics of the incidence of arterial hypertension (AH), 2 type diabetes mellitus (DM), and obesity as the main risk factor of these conditions, combinations between them and certain circulation disorders in the patients admitted to our clinic from 2003 to 2011. We analysed 25,451 case histories. Patients were regarded as having AH, DM, obesity, coronary heart disease, cardiac rhythm disturbances and cerebovascular disorders if they had verified diagnosis of nosological forms corresponding to the respective ICD-10 codes. Their occurrence was calculatedfor 3 three-year periods with reference to the mean age of the patients in different groups. It was shown that increased incidence of AH in the above time periods was associated with the enhanced occurrence of combination of AH and obesity or AH, obesity and DM. Similarly, the increased incidence of DM was associated with the enhanced occurrence of combination DM, AH, and obesity. A significant increase of the mean age was documented only in women with AH and obesity and in men with AH or AH plus obesity. The presence of DM in AH patients had no appreciable effect on the frequency of cerebrovascular pathology that increased in the presence ofAH with obesity.

[Regional features of present-day polymorbidity of internal diseases].

Analysis of transnosological and trans-systemic polymorbidity for 2003-2011 in a general therapy clinic included 23310 patients (9111 men and 14199 women). It was supplemented by comparative analysis of morbidity in southern West Siberia and Yakutiya. The assessment was performed for three age groups (16-39, 40-59, over 60 years). The mean number of nosological forms (transnosological morbidity) and affected systems of organs (trans-systemic morbidity) averaged 5.19 +/- 0.01 and 4.09 +/- 0.01 per patient respectively (4.93 +/- 0.02 and 3.92 +/- 0.02 in men, 5.36 +/- 0.02 and 4.19 +/- 0.01 in women). The prevalence of polymorbidity was significantly higher in women than in men and in Yakutia higher than in West Siberia. The differences tend to be smoothed in recent years. Transnosological morbidity coefficients in male and female residents of Novosibirsk region increased from 4.14 +/- 0.03 and 4.60 +/- 0.04 respectively in 2003-2005 to 5.48 +/- 0.05 and 6.70 +/- 0.06 in 2009-2011 (p < 0.0001). In Yakutiya this growth in men was less pronounced than in a more temperate climate and was practically inapparent in women.

[The prevalence of metabolic syndrome in an organized population].

Triple screening of industrial employees (city of Mirny, West Yakutia) was carried out in 1991-2007 in conformity with the WHO/CINDI protocol designed to elucidate risk factors of chronic non-infectious diseases. The study included 2221 subjects. Metabolic syndrome (MS) was diagnosed based on criteria of NCEP-ATP III Program modified in 2005. The prevalence of MS increased during 17 years more than three-fold in both men and women (from 6 3 to 23.0% and from 9.2 to 32.4% respectively). In other words, it grows continuously. The commonest components in the structure of MS in men and women were arterial hypertension, abdominal obesity, hyperglycemia in 1991 and arterial hypertension, low HDLP cholesterol level, abdominal obesity in 2000 and 2007 (additionally, hypertriglyceridemia in men).

[The increase of carbon dyoxidi production at hypoxia in health subjects].

Pulmonary gas exchange, SpO2 and heart rate at 15-min hypoxia (respiration by air with 0.17; 0.15 and 0.13 oxygen fractions) have been investigated in 24 health subjects. It has been established, results of the group analysis and the results of the individual analysis had been differed. Reaction on hypoxia at the group analysis had been found only at 0.13 02 fraction. It was only hyperventilation. The individual analysis had revealed 4 types of reaction on hypoxia already at 0.17 and 0.15 02 fractions: (1) hyperventilation, (2) decrease of oxygen consumption, (3) increase of ventilation effectiveness, (4) increase of CO2 production. The mechanisms of last reaction are unknown, but we supposed it was connected with anaerobic metabolism. The reactions were detected at light hypoxia (0.17 and 0.15 oxygen fractions) in 90% health subjects when SpO2 decreased to 87-93%. The increase ventilation has been detected at hypoxia within respiration 0.13 oxygen in 60% subjects when SpO2 decreased to 83-87%, while other reactions were nearly absent.

Response to comment on "Hydrogen mapping of the lunar South Pole using the LRO neutron detector experiment LEND".

Critical comments from Lawrence et al. are considered on the capability of the collimated neutron telescope Lunar Exploration Neutron Detector (LEND) on NASA's Lunar Reconnaissance Orbiter (LRO) for mapping lunar epithermal neutrons, as presented in our paper. We present two different analyses to show that our previous estimated count rates are valid and support the conclusions of that paper.

Hydrogen mapping of the lunar south pole using the LRO neutron detector experiment LEND.

Hydrogen has been inferred to occur in enhanced concentrations within permanently shadowed regions and, hence, the coldest areas of the lunar poles. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission was designed to detect hydrogen-bearing volatiles directly. Neutron flux measurements of the Moon's south polar region from the Lunar Exploration Neutron Detector (LEND) on the Lunar Reconnaissance Orbiter (LRO) spacecraft were used to select the optimal impact site for LCROSS. LEND data show several regions where the epithermal neutron flux from the surface is suppressed, which is indicative of enhanced hydrogen content. These regions are not spatially coincident with permanently shadowed regions of the Moon. The LCROSS impact site inside the Cabeus crater demonstrates the highest hydrogen concentration in the lunar south polar region, corresponding to an estimated content of 0.5 to 4.0% water ice by weight, depending on the thickness of any overlying dry regolith layer. The distribution of hydrogen across the region is consistent with buried water ice from cometary impacts, hydrogen implantation from the solar wind, and/or other as yet unknown sources.

Experiment LEND of the NASA Lunar Reconnaissance Orbiter for high-resolution mapping of neutron emission of the Moon.

The scientific objectives of neutron mapping of the Moon are presented as 3 investigation tasks of NASA's Lunar Reconnaissance Orbiter mission. Two tasks focus on mapping hydrogen content over the entire Moon and on testing the presence of water-ice deposits at the bottom of permanently shadowed craters at the lunar poles. The third task corresponds to the determination of neutron contribution to the total radiation dose at an altitude of 50 km above the Moon. We show that the Lunar Exploration Neutron Detector (LEND) will be capable of carrying out all 3 investigations. The design concept of LEND is presented together with results of numerical simulations of the instrument's sensitivity for hydrogen detection. The sensitivity of LEND is shown to be characterized by a hydrogen detection limit of about 100 ppm for a polar reference area with a radius of 5 km. If the presence of ice deposits in polar "cold traps" is confirmed, a unique record of many millions of years of lunar history would be obtained, by which the history of lunar impacts could be discerned from the layers of water ice and dust. Future applications of a LEND-type instrument for Mars orbital observations are also discussed.

The Dynamic Albedo of Neutrons (DAN) experiment for NASA's 2009 Mars Science Laboratory.

We present a summary of the physical principles and design of the Dynamic Albedo of Neutrons (DAN) instrument onboard NASA's 2009 Mars Science Laboratory (MSL) mission. The DAN instrument will use the method of neutron-neutron activation analysis in a space application to study the abundance and depth distribution of water in the martian subsurface along the path of the MSL rover.

Some pathophysiological regularities of formation of digestive diseases in population newly coming to the North.

OBJECTIVES: The purpose of the work was to reveal some pathophysiological regularities of digestive diseases (DD) development, depending on a period of living in the North. STUDY DESIGN: A total of 1,014 workers of industrial enterprises in Mirny-city (Yakutia) have been screened according to the WHO\ CINDI program. DD have been revealed in 321 patients. Dynamics of the clinical manifestations of DD has been analyzed depending on a period of living in the North with time intervals 0-5 years, 5-9 years, 10-29 years, 30 years and more. METHODS: There have been defined the content of cortisol, insulin, total cholesterol, triglycerides, alpha-cholesterol, neutrophils' activity on lysosomecation test with their percent distribution in blood serum. RESULTS AND CONCLUSION: It is stated that at digestive diseases, the hormonal-metabolic indices depend on a period of living in the North. The phase dynamics of changes of lipid, cortisol, insulin of cationic protein in blood neutrophils has been revealed. The data presented give more deep information about formation mechanisms of DD pathology.

The 2000 canine distemper epidemic in Caspian seals (Phoca caspica): pathology and analysis of contributory factors.

More than 10,000 Caspian seals (Phoca caspica) were reported dead in the Caspian Sea during spring and summer 2000. We performed necropsies and extensive laboratory analyses on 18 seals, as well as examination of the pattern of strandings and variation in weather in recent years, to identify the cause of mortality and potential contributory factors. The monthly stranding rate in 2000 was up to 2.8 times the historic mean. It was preceded by an unusually mild winter, as observed before in mass mortality events of pinnipeds. The primary diagnosis in 11 of 13 seals was canine distemper, characterized by broncho-interstitial pneumonia, lymphocytic necrosis and depletion in lymphoid organs, and the presence of typical intracytoplasmic inclusion bodies in multiple epithelia. Canine distemper virus infection was confirmed by phylogenetic analysis of reverse transcriptase-polymerase chain reaction products. Organochlorine and zinc concentrations in tissues of seals with canine distemper were comparable to those of Caspian seals in previous years. Concurrent bacterial infections that may have contributed to the mortality of the seals included Bordetella bronchiseptica (4/8 seals), Streptococcus phocae (3/8), Salmonella dublin (1/8), and S. choleraesuis (1/8). A newly identified bacterium, Corynebacterium caspium, was associated with balanoposthitis in one seal. Several infectious and parasitic organisms, including poxvirus, Atopobacter phocae, Eimeria- and Sarcocystis-like organisms, and Halarachne sp. were identified in Caspian seals for the first time.

An exceptionally bright flare from SGR 1806-20 and the origins of short-duration gamma-ray bursts.

Soft-gamma-ray repeaters (SGRs) are galactic X-ray stars that emit numerous short-duration (about 0.1 s) bursts of hard X-rays during sporadic active periods. They are thought to be magnetars: strongly magnetized neutron stars with emissions powered by the dissipation of magnetic energy. Here we report the detection of a long (380 s) giant flare from SGR 1806-20, which was much more luminous than any previous transient event observed in our Galaxy. (In the first 0.2 s, the flare released as much energy as the Sun radiates in a quarter of a million years.) Its power can be explained by a catastrophic instability involving global crust failure and magnetic reconnection on a magnetar, with possible large-scale untwisting of magnetic field lines outside the star. From a great distance this event would appear to be a short-duration, hard-spectrum cosmic gamma-ray burst. At least a significant fraction of the mysterious short-duration gamma-ray bursts may therefore come from extragalactic magnetars.

CO2 snow depth and subsurface water-ice abundance in the northern hemisphere of Mars.

Observations of seasonal variations of neutron flux from the high-energy neutron detector (HEND) on Mars Odyssey combined with direct measurements of the thickness of condensed carbon dioxide by the Mars Orbiter Laser Altimeter (MOLA) on Mars Global Surveyor show a latitudinal dependence of northern winter deposition of carbon dioxide. The observations are also consistent with a shallow substrate consisting of a layer with water ice overlain by a layer of drier soil. The lower ice-rich layer contains between 50 and 75 weight % water, indicating that the shallow subsurface at northern polar latitudes on Mars is even more water rich than that in the south.