Radiation and Dust Sensor for Mars Environmental Dynamic Analyzer Onboard M2020 Rover.

The Radiation and Dust Sensor is one of six sensors of the Mars Environmental Dynamics Analyzer onboard the Perseverance rover from the Mars 2020 NASA mission. Its primary goal is to characterize the airbone dust in the Mars atmosphere, inferring its concentration, shape and optical properties. Thanks to its geometry, the sensor will be capable of studying dust-lifting processes with a high temporal resolution and high spatial coverage. Thanks to its multiwavelength design, it will characterize the solar spectrum from Mars' surface. The present work describes the sensor design from the scientific and technical requirements, the qualification processes to demonstrate its endurance on Mars' surface, the calibration activities to demonstrate its performance, and its validation campaign in a representative Mars analog. As a result of this process, we obtained a very compact sensor, fully digital, with a mass below 1 kg and exceptional power consumption and data budget features.

Prevalence, awareness, treatment and control of diabetes and impaired fasting glucose in the Southern Cone of Latin America.

AIMS: To determine the prevalence, treatment and control of diabetes mellitus (DM) and impaired fasting glucose (IFG) as well as associated factors in the adult population of four cities of the Southern Cone of Latin America (SCLA). METHODS: This is a cross-sectional population-based study that included 7407 adults between 35 and 74 years old in four cities of the SCLA: Temuco (Chile), Marcos Paz and Bariloche (Argentina), and Pando-Barros Blancos (Uruguay). DM was defined as fasting plasma glucose ≥126 mg/dL or self-reported history of diabetes. Awareness, treatment, and control of DM were defined as subjects self-reporting a DM previous diagnosis, the use of a prescription medication or nonpharmacological intervention for DM, and fasting plasma glucose <126 mg/dl, respectively. RESULTS: Prevalence of DM varied among cities, between 8.4% in Bariloche and 14.3% in Temuco. Prevalence of IFG varied at different sites, from 3.5% in Barros Blancos to 6.8% in Marcos Paz. Of the total number of people with diabetes, 20% were newly diagnosed at the time of the study. Overall, 79.8% of patients with diabetes were aware of their condition. The treatment and control rate were 58.8% and 46.2%, respectively. Older age, family history of diabetes, lower educational attainment, overweight, obesity, central obesity, low physical activity, hypertension, hypercholesterolemia and hypertriglyceridemia were all significantly associated with an increased risk of diabetes. CONCLUSIONS: The prevalence of DM and IFG in the adult population of the SCLA is high and varies among cities. These conditions represent a public health challenge since the rates of awareness, treatment, and control are still low.

Prevalence, Distributions and Determinants of Obesity and Central Obesity in the Southern Cone of America.

BACKGROUND: Obesity is a major determinant of cardiovascular disease in South America. However, population-based data are limited. METHODS: A total of 7,524 women and men, aged 35 to 74 years old, were randomly selected from 4 cities in the Southern Cone of Latin America between February 2010 and December 2011. Obesity clinical measurements and cardiovascular risk factors were measured using standard methodology. RESULTS: The prevalence of obesity and central obesity were 35.7% and 52.9%, respectively. The prevalence of obesity and central obesity were higher in women, and even higher in women with lower education compared with women with higher education. In men and women obesity was associated with a higher prevalence of diabetes, odds ratio (OR) 2.38 (95% Confidence Interval [CI]: 1.86 to 3.05) and 3.01 (95%CI 2.42 to 3.74) respectively, hypertension (OR 2.79 (95%CI 2.32 to 3.36) and 2.40 (95%CI 2.05 to 2.80) respectively, dyslipidemia (OR 1.83 (95%CI 1.50 to 2.24) and 1.69 (95%CI 1.45 to 1.98), respectively, low physical activity (OR 1.38(95%CI 1.14 to 1.68) and 1.38 (95%CI 1.18 to 1.62) respectively and a lower prevalence of smoking (OR, 0.65 (95%CI 0.53 to 0.80) and 0.58(95%CI 0.48 to 0.70) respectively. CONCLUSIONS: Obesity and central obesity are highly prevalent in the general population in the Southern Cone of Latin America and are strongly associated with cardiovascular risk factor prevalence. These data suggest that efforts toward prevention, treatment, and control of obesity should be a public health priority in the Southern Cone of Latin America.

Prevalence, Awareness, Treatment, and Control of Hypertension in the Southern Cone of Latin America.

BACKGROUND: Hypertension is the leading global preventable risk factor for premature death. While hypertension prevalence has been declining in high-income countries, it has increased continuously in low- and middle-income countries. METHODS: We conducted a cross-sectional survey in 7,524 women and men aged 35-74 years from randomly selected samples in 4 cities (Bariloche and Marcos Paz, Argentina; Temuco, Chile; and Pando-Barros Blancos, Uruguay) in 2010-2011. Three blood pressure (BP) measurements were obtained by trained observers using a standard mercury sphygmomanometer. Hypertension was defined as a mean systolic BP ≥140mm Hg and/or diastolic BP ≥90mm Hg and/or use of antihypertensive medications. RESULTS: An estimated 42.5% of the study population (46.6% of men and 38.7% of women) had hypertension and an estimated 32.5% (36.0% of men and 29.4% of women) had prehypertension. Approximately 63.0% of adults with hypertension (52.5% of men and 74.3% of women) were aware of their disease condition, 48.7% (36.1% of men and 62.1% of women) were taking prescribed medications to lower their BP, and only 21.1% of all hypertensive patients (13.8% of men and 28.9% of women) and 43.3% of treated hypertensive patients (38.1% of men and 46.5% of women) achieved BP control. CONCLUSIONS: This study indicates that the prevalence of hypertension is high while awareness, treatment, and control are low in the general population in the Southern Cone of Latin America. These data call for bold actions at regional and national levels to implement effective, practical, and sustainable intervention programs aimed to improve hypertension prevention, detection, and control.

Multiple cardiometabolic risk factors in the Southern Cone of Latin America: a population-based study in Argentina, Chile, and Uruguay.

BACKGROUND: Cardiovascular disease is a major cause of death, and its mortality is increasing in Latin America. However, population-based data on cardiovascular disease risk factors are sparse in these countries. METHODS: A total of 7524 men and women, aged 35 to 74 years old, were recruited between February 2010 and December 2011 from randomly selected samples in 4 cities (Bariloche and Marcos Paz, Argentina; Temuco, Chile; and Pando-Barros Blancos, Uruguay) in the Southern Cone of Latin America. Cardiovascular risk factors were measured using standard methods by trained and certified observers. RESULTS: Approximately 85.5% of adults ate less than five servings of fruit or vegetables per day, 35.2% engaged in low physical activity, and 29.7% currently smoked cigarettes. The prevalences of obesity, central obesity, hypertension, chronic kidney disease, dyslipidemia, diabetes, and metabolic syndrome were 35.7%, 52.9%, 40.8%, 2.0%, 58.4%, 12.4%, and 37.4%, respectively. The proportion of individuals with ≥3 cardiovascular risk factors, including low intake of fruit and vegetables, low physical activity, current cigarette smoking, obesity or central obesity, hypertension, chronic kidney disease, dyslipidemia, and diabetes, was 68.3%, and the proportion of individuals with ≥3 cardiometabolic risk factors, including obesity or central obesity, hypertension, chronic kidney disease, dyslipidemia, and diabetes, was 22.9%. CONCLUSIONS: Cardiovascular disease risk factors are highly prevalent in the general population in the Southern Cone of Latin America. These data suggest that national efforts on the prevention, treatment, and control of cardiovascular risk factors should be a public health priority in the Southern Cone of Latin America.

Prokaryotic communities and operating metabolisms in the surface and the permafrost of Deception Island (Antarctica).

In this study we examined the microbial community composition and operating metabolisms on the surface and in the permafrost of Deception Island, (Antarctica) with an on site antibody microarray biosensor. Samples (down to a depth of 4.2 m) were analysed with LDChip300 (Life Detector Chip), an immunosensor containing more than 300 antibodies targeted to bacterial and archaeal antigens. The immunograms showed positive antigen-antibody reactions in all surface samples (lichens, pyroclasts) and the top layer of the permafrost. The results indicated the presence of exopolysaccharides, bacteria belonging to the Alpha-, Delta- and Gammaproteobacteria, Bacteroidetes, Gram-positive Actinobacteria and Firmicutes, as well as archaeal species, most probably Methanobacterium spp. Positive reactions with antibodies to proteins and peptides revealed the presence of nitrogen fixation (NifHD, GlnB, HscA), methanogenic (McrB), iron homeostasis and iron scavenging (ferritins and DPS proteins) proteins, as well as ABC transporters, which indicated that these processes were operating at the time of sampling. These results were validated with other molecular ecology techniques such as oligonucleotide microarrays, 16S bacterial rRNA gene sequence analysis, aerobic viable counts and microscopy. Molecular ecology results showed a differentiated pattern along the depth of the drill, being the top active layer the most diverse, with Acidobacteria, Actinobacteria, Proteobacteria, Bacteroidetes and the phototrophs Cyanobacteria and Chloroflexi as dominant groups. Actinobacteria and Firmicutes were dominant in depths from 0.5 to 2 m, and Betaproteobacteria from 3 to 4.2 m. The geochemical analysis revealed the presence of low molecular weight organic acids (acetate, formate) which could be used by microorganisms as energy sources for sulfate, nitrate and metal reduction under anaerobic conditions.

A microbial oasis in the hypersaline Atacama subsurface discovered by a life detector chip: implications for the search for life on Mars.

The Atacama Desert has long been considered a good Mars analogue for testing instrumentation for planetary exploration, but very few data (if any) have been reported about the geomicrobiology of its salt-rich subsurface. We performed a Mars analogue drilling campaign next to the Salar Grande (Atacama, Chile) in July 2009, and several cores and powder samples from up to 5 m deep were analyzed in situ with LDChip300 (a Life Detector Chip containing 300 antibodies). Here, we show the discovery of a hypersaline subsurface microbial habitat associated with halite-, nitrate-, and perchlorate-containing salts at 2 m deep. LDChip300 detected bacteria, archaea, and other biological material (DNA, exopolysaccharides, some peptides) from the analysis of less than 0.5 g of ground core sample. The results were supported by oligonucleotide microarray hybridization in the field and finally confirmed by molecular phylogenetic analysis and direct visualization of microbial cells bound to halite crystals in the laboratory. Geochemical analyses revealed a habitat with abundant hygroscopic salts like halite (up to 260 g kg(-1)) and perchlorate (41.13 µg g(-1) maximum), which allow deliquescence events at low relative humidity. Thin liquid water films would permit microbes to proliferate by using detected organic acids like acetate (19.14 µg g(-1)) or formate (76.06 µg g(-1)) as electron donors, and sulfate (15875 µg g(-1)), nitrate (13490 µg g(-1)), or perchlorate as acceptors. Our results correlate with the discovery of similar hygroscopic salts and possible deliquescence processes on Mars, and open new search strategies for subsurface martian biota. The performance demonstrated by our LDChip300 validates this technology for planetary exploration, particularly for the search for life on Mars.

Detection and follow-up of chronic obstructive pulmonary disease (COPD) and risk factors in the Southern Cone of Latin America: the pulmonary risk in South America (PRISA) study.

BACKGROUND: The World Health Organization has estimated that by 2030, chronic obstructive pulmonary disease will be the third leading cause of death worldwide. Most knowledge of chronic obstructive pulmonary disease is based on studies performed in Europe or North America and little is known about the prevalence, patient characteristics and change in lung function over time in patients in developing countries, such as those of Latin America. This lack of knowledge is in sharp contrast to the high levels of tobacco consumption and exposure to biomass fuels exhibited in Latin America, both major risk factors for the development of chronic obstructive pulmonary disease. Studies have also demonstrated that most Latin American physicians frequently do not follow international chronic obstructive pulmonary disease diagnostic and treatment guidelines. The PRISA Study will expand the current knowledge regarding chronic obstructive pulmonary disease and risk factors in Argentina, Chile and Uruguay to inform policy makers and health professionals on the best policies and practices to address this condition. METHODS/DESIGN: PRISA is an observational, prospective cohort study with at least four years of follow-up. In the first year, PRISA has employed a randomized three-staged stratified cluster sampling strategy to identify 6,000 subjects from Marcos Paz and Bariloche, Argentina, Temuco, Chile, and Canelones, Uruguay. Information, such as comorbidities, socioeconomic status and tobacco and biomass exposure, will be collected and spirometry, anthropometric measurements, blood sampling and electrocardiogram will be performed. In year four, subjects will have repeat measurements taken. DISCUSSION: There is no longitudinal data on chronic obstructive pulmonary disease incidence and risk factors in the southern cone of Latin America, therefore this population-based prospective cohort study will fill knowledge gaps in the prevalence and incidence of chronic obstructive pulmonary disease, patient characteristics and changes in lung function over time as well as quality of life and health care resource utilization. Information gathered during the PRISA Study will inform public health interventions and prevention practices to reduce risk of COPD in the region.

SOLID3: a multiplex antibody microarray-based optical sensor instrument for in situ life detection in planetary exploration.

The search for unequivocal signs of life on other planetary bodies is one of the major challenges for astrobiology. The failure to detect organic molecules on the surface of Mars by measuring volatile compounds after sample heating, together with the new knowledge of martian soil chemistry, has prompted the astrobiological community to develop new methods and technologies. Based on protein microarray technology, we have designed and built a series of instruments called SOLID (for "Signs Of LIfe Detector") for automatic in situ detection and identification of substances or analytes from liquid and solid samples (soil, sediments, or powder). Here, we present the SOLID3 instrument, which is able to perform both sandwich and competitive immunoassays and consists of two separate functional units: a Sample Preparation Unit (SPU) for 10 different extractions by ultrasonication and a Sample Analysis Unit (SAU) for fluorescent immunoassays. The SAU consists of five different flow cells, with an antibody microarray in each one (2000 spots). It is also equipped with an exclusive optical package and a charge-coupled device (CCD) for fluorescent detection. We demonstrated the performance of SOLID3 in the detection of a broad range of molecular-sized compounds, which range from peptides and proteins to whole cells and spores, with sensitivities at 1-2 ppb (ng mL⁻¹) for biomolecules and 104 to 10³ spores per milliliter. We report its application in the detection of acidophilic microorganisms in the Río Tinto Mars analogue and report the absence of substantial negative effects on the immunoassay in the presence of 50 mM perchlorate (20 times higher than that found at the Phoenix landing site). Our SOLID instrument concept is an excellent option with which to detect biomolecules because it avoids the high-temperature treatments that may destroy organic matter in the presence of martian oxidants.

Classification of modern and old Río Tinto sedimentary deposits through the biomolecular record using a life marker biochip: implications for detecting life on Mars.

The particular mineralogy formed in the acidic conditions of the Río Tinto has proven to be a first-order analogue for the acid-sulfate aqueous environments of Mars. Therefore, studies about the formation and preservation of biosignatures in the Río Tinto will provide insights into equivalent processes on Mars. We characterized the biomolecular patterns recorded in samples of modern and old fluvial sediments along a segment of the river by means of an antibody microarray containing more than 200 antibodies (LDCHIP200, for Life Detector Chip) against whole microorganisms, universal biomolecules, or environmental extracts. Samples containing 0.3-0.5 g of solid material were automatically analyzed in situ by the Signs Of LIfe Detector instrument (SOLID2), and the results were corroborated by extensive analysis in the laboratory. Positive antigen-antibody reactions indicated the presence of microbial strains or high-molecular-weight biopolymers that originated from them. The LDCHIP200 results were quantified and subjected to a multivariate analysis for immunoprofiling. We associated similar immunopatterns, and biomolecular markers, to samples with similar sedimentary age. Phyllosilicate-rich samples from modern fluvial sediments gave strong positive reactions with antibodies against bacteria of the genus Acidithiobacillus and against biochemical extracts from Río Tinto sediments and biofilms. These samples contained high amounts of sugars (mostly polysaccharides) with monosaccharides like glucose, rhamnose, fucose, and so on. By contrast, the older deposits, which are a mix of clastic sands and evaporites, showed only a few positives with LDCHIP200, consistent with lower protein and sugar content. We conclude that LDCHIP200 results can establish a correlation between microenvironments, diagenetic stages, and age with the biomarker profile associated with a sample. Our results would help in the search for putative martian biomarkers in acidic deposits with similar diagenetic maturity. Our LDCHIP200 and SOLID-like instruments may be excellent tools for the search for molecular biomarkers on Mars or other planets.

SOLID2: an antibody array-based life-detector instrument in a Mars Drilling Simulation Experiment (MARTE).

A field prototype of an antibody array-based life-detector instrument, Signs Of LIfe Detector (SOLID2), has been tested in a Mars drilling mission simulation called MARTE (Mars Astrobiology Research and Technology Experiment). As one of the analytical instruments on the MARTE robotic drilling rig, SOLID2 performed automatic sample processing and analysis of ground core samples (0.5 g) with protein microarrays that contained 157 different antibodies. Core samples from different depths (down to 5.5 m) were analyzed, and positive reactions were obtained in antibodies raised against the Gram-negative bacterium Leptospirillum ferrooxidans, a species of the genus Acidithiobacillus (both common microorganisms in the Río Tinto area), and extracts from biofilms and other natural samples from the Río Tinto area. These positive reactions were absent when the samples were previously subjected to a high-temperature treatment, which indicates the biological origin and structural dependency of the antibody-antigen reactions. We conclude that an antibody array-based life-detector instrument like SOLID2 can detect complex biological material, and it should be considered as a potential analytical instrument for future planetary missions that search for life.