The longitudinal behavioral effects of acute exposure to galactic cosmic radiation in female C57BL/6J mice: Implications for deep space missions, female crews, and potential antioxidant countermeasures.

Galactic cosmic radiation (GCR) is an unavoidable risk to astronauts that may affect mission success. Male rodents exposed to 33-beam-GCR (33-GCR) show short-term cognitive deficits but reports on female rodents and long-term assessment are lacking. We asked: What are the longitudinal behavioral effects of 33-GCR on female mice? Also, can an antioxidant/anti-inflammatory compound (CDDO-EA) mitigate the impact of 33-GCR? Mature (6-month-old) C57BL/6J female mice received CDDO-EA (400 µg/g of food) or a control diet (vehicle, Veh) for 5 days and Sham-irradiation (IRR) or whole-body 33-GCR (0.75Gy) on the 4th day. Three-months post-IRR, mice underwent two touchscreen-platform tests: (1) location discrimination reversal (tests behavior pattern separation and cognitive flexibility, abilities reliant on the dentate gyrus) and (2) stimulus-response learning/extinction. Mice then underwent arena-based behavior tests (e.g. open field, 3-chamber social interaction). At the experiment's end (14.25-month post-IRR), an index relevant to neurogenesis was quantified (doublecortin-immunoreactive [DCX+] dentate gyrus immature neurons). Female mice exposed to Veh/Sham vs. Veh/33-GCR had similar pattern separation (% correct to 1st reversal). There were two effects of diet: CDDO-EA/Sham and CDDO-EA/33-GCR mice had better pattern separation vs. their respective control groups (Veh/Sham, Veh/33-GCR), and CDDO-EA/33-GCR mice had better cognitive flexibility (reversal number) vs. Veh/33-GCR mice. One radiation effect/CDDO-EA countereffect also emerged: Veh/33-GCR mice had slower stimulus-response learning (days to completion) vs. all other groups, including CDDO-EA/33-GCR mice. In general, all mice showed normal anxiety-like behavior, exploration, and habituation to novel environments. There was also a change relevant to neurogenesis: Veh/33-GCR mice had fewer DCX+ dentate gyrus immature neurons vs. Veh/Sham mice. Our study implies space radiation is a risk to a female crew's longitudinal mission-relevant cognitive processes and CDDO-EA is a potential dietary countermeasure for space-radiation CNS risks.

Assessment of Eye Care Apps for Children and Adolescents Based on the Mobile App Rating Scale: Content Analysis and Quality Assessment.

BACKGROUND: In China, the current situation of myopia among children and adolescents is very serious. Prevention and control of myopia are inhibited by the lack of medical resources and the low awareness about eye care. Nevertheless, mobile apps provide an effective means to solve these problems. Since the health app market in China is still immature, it has become particularly important to conduct a study to assess the quality of eye-care apps to facilitate the development of better eye-care service strategies. OBJECTIVE: This study aimed to evaluate the quality, functionality, medical evidence, and professional background of eye-care apps targeting children and adolescents in the Chinese app stores. METHODS: A systematic search on iOS and Android app stores was performed to identify eye-care apps for children and adolescents. The general characteristics, development context, and functional features of the apps were described. Quality assessment of the apps was completed by 2 independent researchers using the Mobile App Rating Scale. RESULTS: This study included 29 apps, of which 17 (59%) were developed by commercial organizations and 12 (41%) had a design with relevant scientific basis. The main built-in functions of these apps include self-testing (18/29, 62%), eye exercises (16/29, 55%), and eye-care education (16/29, 55%). The mean overall quality of eye-care apps was 3.49 (SD 0.33), with a score ranging from 2.89 to 4.39. The overall Mobile App Rating Scale score exhibited a significant positive correlation with the subscale scores (r=0.81-0.91; P<.001). In addition, although most apps provided basic eye-care features, there are some deficiencies. For example, only a few apps were developed with the participation of medical organizations or professional ophthalmologists, and most of the apps were updated infrequently, failing to provide the latest eye-care information and technology in a timely manner. CONCLUSIONS: In general, the quality of eye-care apps for children and teenagers in Chinese app stores is good. These apps fulfill users' needs for eye-care services to a certain extent, but they still suffer from insufficient medical background, low user engagement, and untimely updates. In order to further improve the effectiveness of eye-care apps, cooperation with medical institutions and professional ophthalmologists should be strengthened to enhance the scientific and authoritative nature of the apps. At the same time, interactive features and regular updates should be added to enhance user participation and the continuity of the apps. This study provides a reference for future development or improvement of eye-care apps, which can help promote myopia prevention and control.

The Impact of Gamified Smartphone App Interventions on Behaviour and Metabolic Outcomes in Individuals at Risk of Cardiovascular Disease.

This study examines gamified smartphone app interventions for improving lifestyle choices and cardiometabolic health in adults at risk for cardiovascular disease. A systematic review of six databases compared gamified interventions with conventional methods. Despite a functionality rating of 4.07, user engagement was lacking. Findings suggest that incorporating game elements into health apps can promote lifestyle changes and improve cardiometabolic health, guiding future digital health strategies to reduce cardiovascular disease risk.

Metal-support interaction in supported Pt single-atom catalyst promotes lattice oxygen activation to achieve complete oxidation of acetone at low concentrations.

A precious metal catalyst with loaded Pt single atoms was prepared and used for the complete oxidation of C3H6O. Detailed results show that the T100 of the 1.5Pt SA/γ-Al2O3 catalyst in the oxidation process of acetone is 250 °C, the TOF of Pt is 1.09 × 10-2 s-1, and the catalyst exhibits good stability. Characterization reveals that the high dispersion of Pt single atoms and strong interaction with the carrier improve the redox properties of the catalyst, enhancing the adsorption and dissociation capability of gaseous oxygen. DFT calculations show that after the introduction of Pt, the oxygen vacancy formation energy on the catalyst surface is reduced to 1.2 eV, and PDOS calculations prove that electrons on Pt atoms can be quickly transferred to O atoms, increasing the number of electrons on the σp * bond and promoting the escape of lattice oxygen. In addition, in situ DRIFTS and adsorption experiments indicate that the C3H6O oxidation process follows the Mars-van Krevelen reaction mechanism, and CH2 =C(CH3)=O(ads), O* (O2-), formate, acetate, and carbonate are considered as the main intermediate species and/or transients in the reaction process. Particularly, the activation rate of O2 and the cleavage of the -C-C- bond are the main rate-determining steps in the oxidation of C3H6O. This work will further enhance the study of the oxidation mechanism of oxygenated volatile organic pollutants over loaded noble metal catalysts.

Hyperexpansion of genetic diversity and metabolic capacity of extremophilic bacteria and archaea in ancient Andean lake sediments.

BACKGROUND: The Andean Altiplano hosts a repertoire of high-altitude lakes with harsh conditions for life. These lakes are undergoing a process of desiccation caused by the current climate, leaving terraces exposed to extreme atmospheric conditions and serving as analogs to Martian paleolake basins. Microbiomes in Altiplano lake terraces have been poorly studied, enclosing uncultured lineages and a great opportunity to understand environmental adaptation and the limits of life on Earth. Here we examine the microbial diversity and function in ancient sediments (10.3-11 kyr BP (before present)) from a terrace profile of Laguna Lejía, a sulfur- and metal/metalloid-rich saline lake in the Chilean Altiplano. We also evaluate the physical and chemical changes of the lake over time by studying the mineralogy and geochemistry of the terrace profile. RESULTS: The mineralogy and geochemistry of the terrace profile revealed large water level fluctuations in the lake, scarcity of organic carbon, and high concentration of SO42--S, Na, Cl and Mg. Lipid biomarker analysis indicated the presence of aquatic/terrestrial plant remnants preserved in the ancient sediments, and genome-resolved metagenomics unveiled a diverse prokaryotic community with still active microorganisms based on in silico growth predictions. We reconstructed 591 bacterial and archaeal metagenome-assembled genomes (MAGs), of which 98.8% belonged to previously unreported species. The most abundant and widespread metabolisms among MAGs were the reduction and oxidation of S, N, As, and halogenated compounds, as well as aerobic CO oxidation, possibly as a key metabolic trait in the organic carbon-depleted sediments. The broad redox and CO2 fixation pathways among phylogenetically distant bacteria and archaea extended the knowledge of metabolic capacities to previously unknown taxa. For instance, we identified genomic potential for dissimilatory sulfate reduction in Bacteroidota and α- and γ-Proteobacteria, predicted an enzyme for ammonia oxidation in a novel Actinobacteriota, and predicted enzymes of the Calvin-Benson-Bassham cycle in Planctomycetota, Gemmatimonadota, and Nanoarchaeota. CONCLUSIONS: The high number of novel bacterial and archaeal MAGs in the Laguna Lejía indicates the wide prokaryotic diversity discovered. In addition, the detection of genes in unexpected taxonomic groups has significant implications for the expansion of microorganisms involved in the biogeochemical cycles of carbon, nitrogen, and sulfur. Video Abstract.

Magnetic Resonance Imaging of Total Ankle Arthroplasty: State-of-The-Art Assessment of Implant-Related Pain and Dysfunction.

Total ankle arthroplasty (TAA) is an effective alternative for treating patients with end-stage ankle degeneration, improving mobility, and providing pain relief. Implant survivorship is constantly improving; however, complications occur. Many causes of pain and dysfunction after total ankle arthroplasty can be diagnosed accurately with clinical examination, laboratory, radiography, and computer tomography. However, when there are no or inconclusive imaging findings, magnetic resonance imaging (MRI) is highly accurate in identifying and characterizing bone resorption, osteolysis, infection, osseous stress reactions, nondisplaced fractures, polyethylene damage, nerve injuries and neuropathies, as well as tendon and ligament tears. Multiple vendors offer effective, clinically available MRI techniques for metal artifact reduction MRI of total ankle arthroplasty. This article reviews the MRI appearances of common TAA implant systems, clinically available techniques and protocols for metal artifact reduction MRI of TAA implants, and the MRI appearances of a broad spectrum of TAA-related complications.

Health Literacy and Medication Adherence Among Patients with Type 2 Diabetes in Jordan: A Cross-Sectional Study.

Background: Improving health literacy has been found to play a significant role in enhancing medication adherence in patients with type 2 diabetes. Purpose: The present study aims to evaluate health literacy and its association with medication adherence among diabetic patients in Jordan. Patients and Methods: This cross-sectional study included 400 diabetic patients, predominantly female (68.8%), with a median age of 58 years, attending the endocrinology outpatient clinic at Albasheer Hospital in Amman, Jordan, between August and December 2023. Patients were recruited using convenience sampling, including those aged 18 and older, literate, diagnosed with T2DM for at least one year, and on at least one medication for T2DM. Sample size was calculated based on the Events Per Variable (EPV) criterion to ensure sufficient power for logistic regression analysis. Data were collected using two validated instruments: the Jordanian Diabetic Health Literacy Questionnaire (JDHLQ), assessing health literacy, and the Medication Adherence Report Scale (MARS-5), measuring medication adherence. A binary logistic regression model was constructed to identify variables associated with adherence levels. Results: The study enrolled 400 diabetic patients (females =68.8%). While most of the participants (70.3%) reported high adherence levels, results revealed a window for health literacy improvement as the median for the JDHLQ score was 22 (ranging from 18 to 25) out of a maximum possible score of 32. More than half of the participants replied "never" to "I forget to take my medications", followed by "I stop taking my medications for a while". Conclusion: The binary regression model revealed that a higher JDHLQ score significantly increased the odds of a high adherence level. The significant association between improved health literacy and medication adherence necessitates the implementation of educational campaigns for enhancing literacy and hence medication adherence among patients with type 2 diabetes.

Liquid water in the Martian mid-crust.

Large volumes of liquid water transiently existed on the surface of Mars more than 3 billion years ago. Much of this water is hypothesized to have been sequestered in the subsurface or lost to space. We use rock physics models and Bayesian inversion to identify combinations of lithology, liquid water saturation, porosity, and pore shape consistent with the constrained mid-crust (∼11.5 to 20 km depths) seismic velocities and gravity near the InSight lander. A mid-crust composed of fractured igneous rocks saturated with liquid water best explains the existing data. Our results have implications for understanding Mars' water cycle, determining the fates of past surface water, searching for past or extant life, and assessing in situ resource utilization for future missions.

Factors Influencing Mental Well-being Among Older Malaysians.

Older adults are at greater risk of mental health issues. This study examined the factors influencing mental well-being among 2230 Malaysian older adults, using data from the 2018 to 2019 Malaysia Ageing and Retirement Survey. The World Health Organization-Five Well-Being Index (WHO-5) was used to assess mental well-being, and linear regression analysis identified the significant factors. Women had lower mental well-being scores than men (P = .012, ß = -0.016). Chinese (P = .024, ß = -0.020), Indian (P < .001, ß = -0.043), and other ethnicities (P < .001, ß = -0.031) reported lower scores than Malays. The factors associated with better well-being were secondary (P = .001, ß = 0.032) and tertiary education (P < .001, ß = 0.063), and good (P < .001, ß = 0.081) and moderate (P < .001, ß = 0.038) health status. Diseases-limiting activities were associated with poor well-being (P < .001, ß = -0.030). Support from family (P < .001, ß = 0.062) and friends (P < .001, ß = 0.032), social activity participation (P < .001, ß = 0.026), and functional ability (P < .001, ß = 0.043) were significant positive factors. There is a need for targeted interventions to enhance mental health among Malaysian older adults.

Insights into the Quality of Mobile Health Apps: Preliminary Results of an Analysis of MARS Scores.

Many mHelath applications have been developed, and the Mobile App Rating Scale (MARS) is a common tool for assessing them. This study aims to provide mean values for MARS scores found in recent literature. We systematically searched for literature in which MARS was used and analyzed them. MARS values for 5,920 applications from 215 studies were compiled. The mean MARS Quality Score is 3.51. The highest average score was achieved in the Functionality category (3.98), followed by Aesthetics (3.52), Information (3.33), Engagement (3.18) and Subjective (2.72). To the best of our knowledge, this is the first study to calculate average values for the five categories of the MARS and the MARS score based on such an extensive collection of data. The study shows that the overall quality of the applications is above the average value of 2.5.

Medication Adherence to Direct Oral Anticoagulants: Extent and Impact of Side Effects.

Purpose: Arterial and venous thromboembolism are a leading cause of mortality. Direct oral anticoagulants (DOACs) are highly effective in both stroke prevention and prevention of venous thrombotic events. Medication adherence is a prerequisite for optimal protection against thromboembolic complications. Recent studies have shown that good adherence cannot be taken for granted by DOACs. In this cross-sectional study adherence among DOAC users was investigated and associations between beliefs about medication, perceived side effects and adherence were explored. Patients and Methods: We included 100 randomly selected adult DOAC users visiting one of the two participating Dutch community pharmacies in the summer of 2020. The self-reported adherence (primary outcome) was assessed with the Medication Adherence Rating Scale-5 (MARS-5) using three different cut-off scores. Beliefs about DOACs were assessed with the Beliefs about Medicine Questionnaire Specific (BMQ-S), while side effects and side effect burden were assessed with a self-developed questionnaire based on the Lareb Intensive Monitoring (LIM) system. Results: Of the participants, 9% reported non-adherence on the primary MARS-5 cut-off score <24. For the MARS-5 scores <23 and <25 non-adherence percentages of, respectively, 3 and 33% were calculated. Associations were found between adherence and both side effects and side effect burden, regardless of the MARS-5 cut-off score. Bruising and minor bleeds were the most reported side effects (both 20%). For all patients, the necessity beliefs outweighed the concern beliefs. No associations were found between adherence and either gender, indication, DOAC or dosage. Conclusion: This study confirms that adherence in patients on DOACs cannot be taken for granted. High necessity beliefs do not guarantee good adherence, as side effects impair adherence even in patients having high necessity beliefs. Therefore, we recommend that both physicians and pharmacists evaluate both adherence and side effects with these patients on a regular base.

The issue Thrombosis affects many people. Complications like stroke and lung embolism are a major cause of health damage, disability and even death. Direct oral anticoagulants (DOACs) are highly effective drugs at preventing these complications. However, patients need to take their medication properly to get the best protection. Recent studies showed that not all patients consistently take their DOACs. What's new? In this study, we discovered that patients experiencing bothersome side effect were less likely to stick to their medication schedule. The most common side effects reported were bruising and minor bleeding, by 20% each. There were no differences in how well patients took their medication based on gender, medical condition, type of DOAC or prescribed dosage. Most patients believed their medication was necessary for their health. Why is this important? This study shows that side effects hinder patients taking their medication correctly even when they believe their medication is necessary for their health. This means that patients on DOAC therapy who experience side effects may be less protected against stroke and lung embolism. Therefore, we recommend that doctors and pharmacists regularly check in with patients about any side effects they experience and how consistently they take their DOACs. What's next? This study highlights the importance of developing, testing, and implementing practical tools to find and help patients who do not take their DOACs correctly, to ensure they are better protected against blood clots.

Investigating the stability of aromatic carboxylic acids in hydrated magnesium sulfate under UV irradiation to assist detection of organics on Mars.

The Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument onboard the Mars 2020 Perseverance rover detected so far some of the most intense fluorescence signals in association with sulfates analyzing abraded patches of rocks at Jezero crater, Mars. To assess the plausibility of an organic origin of these signals, it is key to understand if organics can survive exposure to ambient Martian UV after exposure by the Perseverance abrasion tool and prior to analysis by SHERLOC. In this work, we investigated the stability of organo-sulfate assemblages under Martian-like UV irradiation and we observed that the spectroscopic features of phthalic and mellitic acid embedded into hydrated magnesium sulfate do not change for UV exposures corresponding to at least 48 Martian sols and, thus, should still be detectable in fluorescence when the SHERLOC analysis takes place, thanks to the photoprotective properties of magnesium sulfate. In addition, different photoproduct bands diagnostic of the parent carboxylic acid molecules could be observed. The photoprotective behavior of hydrated magnesium sulfate corroborates the hypothesis that sulfates might have played a key role in the preservation of organics on Mars, and that the fluorescence signals detected by SHERLOC in association with sulfates could potentially arise from organic compounds.

Molecular Adsorbent Recirculating System in Acute Liver Failure.

Acetaminophen (APAP) overdose is the most common cause of acute liver failure (ALF) in the United States. Liver transplantation (LT) is potentially lifesaving for patients with ALF, but its feasibility in clinical practice is limited. Liver assist devices, such as the Molecular Adsorbent Recirculating System (MARS), are used in some centers as a "bridge" to liver transplantation or as a means of liver recovery, but their role in the treatment of ALF is not well-defined. We present the case of a 44-year-old man with APAP-associated ALF who experienced hepatic recovery after treatment with MARS.

Challenges and innovations in food and water availability for a sustainable Mars colonization.

In recent years, extensive research has been dedicated to Mars exploration and the potential for sustainable interplanetary human colonization. One of the significant challenges in ensuring the survival of life on Mars lies in the production of food as the Martian environment is highly inhospitable to agriculture, rendering it impractical to transport food from Earth. To improve the well-being and quality of life for future space travelers on Mars, it is crucial to develop innovative horticultural techniques and food processing technologies. The unique challenges posed by the Martian environment, such as the lack of oxygen, nutrient-deficient soil, thin atmosphere, low gravity, and cold, dry climate, necessitate the development of advanced farming strategies. This study explores existing knowledge and various technological innovations that can help overcome the constraints associated with food production and water extraction on Mars. The key lies in utilizing resources available on Mars through in-situ resource utilization. Water can be extracted from beneath the ice and from the Martian soil. Furthermore, hydroponics in controlled environment chambers, equipped with nutrient delivery systems and waste recovery mechanisms, have been investigated as a means of cultivating crops on Mars. The inefficiency of livestock production, which requires substantial amounts of water and land, highlights the need for alternative protein sources such as microbial protein, insects, and in-vitro meat. Moreover, the fields of synthetic biology and 3-D food printing hold immense potential in revolutionizing food production and making significant contributions to the sustainability of human life on Mars.

A polymerase chain reaction experiment using Escherichia coli and Mars sand simulant for detection and analysis of extraterrestrial life.

In this study, we conducted polymerase chain reaction (PCR) experiments using Escherichia coli (E. coli) and a Mars sand simulant (Mars Global Simulant MGS-1, Exolith Lab) to detect and analyze potential extraterrestrial life. The targeted DNA sequence is common among the bacterial kingdom on Earth. PCR experiments conducted after alkaline heat extraction, wherein samples with varying amounts of Mars sand simulant were compared, revealed that the simulant interfered with DNA detection. We then conducted PCR experiments following treatment with a sand DNA extraction kit on samples with various E. coli densities. DNA bands for a minimum E. coli density of 900 cells/(g sand) were confirmed, while no DNA bands were visible in the 90 cells/(g sand) sample with and without the Mars sand simulant. The total DNA mass contained in 900 cells was calculated to be 15.3 pg (i.e., 1.53 pg in 0.1 g sand sample we evaluated). We tested and compared the influence of the eluate of Mars sand simulant and DNA adsorption onto Mars sand simulant based on optical absorbance measurements. Our findings suggest that the mechanism by which the Mars sand simulant prevents PCR is through the adsorption of DNA onto the Mars sand simulant.

The Preservation and Spectral Detection of Historic Museum Specimen Microbial Mat Biosignatures Within Martian Dust: Lessons Learned for Mars Exploration and Sample Return.

The key building blocks for life on Mars could be preserved within potentially habitable paleo-depositional settings with their detection possible by utilizing mid-infrared spectroscopy; however, a definite identification and confirmation of organic or even biological origin will require the samples to be returned to Earth. In the present study, Fourier-transform infrared (FTIR) spectroscopic techniques were used to characterize both mineralogical and organic materials within Mars dust simulant JSC Mars-1 and ancient Antarctic cyanobacterial microbial mats from 1901 to 1904 Discovery Expedition. When FTIR spectroscopy is applied to cyanobacterial microbial mat communities, the resulting spectra will reflect the average biochemical composition of the mats rather than taxa-specific spectral patterns of the individual organisms and can thus be considered as a total chemical analysis of the mat colony. This study also highlights the potential difficulties in the detection of these communities on Mars and which spectral biosignatures will be most detectable within geological substrates. Through the creation and analysis of a suite of dried microbial mat material and Martian dust simulant mixtures, the spectral signatures and wavenumber positions of CHx aliphatic hydrocarbons and the C-O and O-H bands of polysaccharides remained detectable and may be detectable within sample mixtures obtained through Mars Sample Return activities.

Variable and Large Losses of Diagnostic Biomarkers After Simulated Cosmic Radiation Exposure in Clay- and Carbonate-Rich Mars Analog Samples.

Mars has been exposed to ionizing radiation for several billion years, and as part of the search for life on the Red Planet, it is crucial to understand the impact of radiation on biosignature preservation. Several NASA and ESA missions are looking for evidence of ancient life in samples collected at depths shallow enough that they have been impacted by galactic cosmic rays (GCRs). In this study, we exposed a diverse set of Mars analog samples to 0.9 Megagray (MGy) of gamma radiation to mimic 15 million years of exposure on the Martian surface. We measured no significant impact of GCRs on the total organic carbon (TOC) and bulk stable C isotopes in samples with initial TOC concentration > 0.1 wt. %; however, diagnostic molecular biosignatures presented a wide range of degradation that didn't correlate to factors like mineralogy, TOC, water content, and surface area. Exposure dating suggests that the surface of Gale crater has been irradiated at more than five times our dose, yet using this relatively low dose and "best-case scenario" geologically recalcitrant biomarkers, large and variable losses were nevertheless evident. Our results empasize the importance of selecting sampling sites at depth or recently exposed at the Martian surface.

Unveiling Challenging Microbial Fossil Biosignatures from Rio Tinto with Micro-to-Nanoscale Chemical and Ultrastructural Imaging.

Understanding the nature and preservation of microbial traces in extreme environments is crucial for reconstructing Earth's early biosphere and for the search for life on other planets or moons. At Rio Tinto, southwestern Spain, ferric oxide and sulfate deposits similar to those discovered at Meridiani Planum, Mars, entomb a diversity of fossilized organisms, despite chemical conditions commonly thought to be challenging for life and fossil preservation. Investigating this unique fossil microbiota can elucidate ancient extremophile communities and the preservation of biosignatures in acidic environments on Earth and, potentially, Mars. In this study, we use an innovative multiscale approach that combines the state-of-the-art synchrotron X-ray nanoimaging methods of ptychographic X-ray computed laminography and nano-X-ray fluorescence to reveal Rio Tinto's microfossils at subcellular resolution. The unprecedented nanoscale views of several different specimens within their geological and geochemical contexts reveal novel intricacies of preserved microbial communities. Different morphotypes, ecological interactions, and possible taxonomic affinities were inferred based on qualitative and quantitative 3D ultrastructural information, whereas diagenetic processes and metabolic affinities were inferred from complementary chemical information. Our integrated nano-to-microscale analytical approach revealed previously invisible microbial and mineral interactions, which complemented and filled a gap of spatial resolution in conventional methods. Ultimately, this study contributes to the challenge of deciphering the faint chemical and morphological biosignatures that can indicate life's presence on the early Earth and on distant worlds.

Modeling the Effects of Protracted Cosmic Radiation in a Human Organ-on-Chip Platform.

Galactic cosmic radiation (GCR) is one of the most serious risks posed to astronauts during missions to the Moon and Mars. Experimental models capable of recapitulating human physiology are critical to understanding the effects of radiation on human organs and developing radioprotective measures against space travel exposures. The effects of systemic radiation are studied using a multi-organ-on-a-chip (multi-OoC) platform containing engineered tissue models of human bone marrow (site of hematopoiesis and acute radiation damage), cardiac muscle (site of chronic radiation damage) and liver (site of metabolism), linked by vascular circulation with an endothelial barrier separating individual tissue chambers from the vascular perfusate. Following protracted neutron radiation, the most damaging radiation component in deep space, a greater deviation of tissue function is observed as compared to the same cumulative dose delivered acutely. Further, by characterizing engineered bone marrow (eBM)-derived immune cells in circulation, 58 unique genes specific to the effects of protracted neutron dosing are identified, as compared to acutely irradiated and healthy tissues. It propose that this bioengineered platform allows studies of human responses to extended radiation exposure in an "astronaut-on-a-chip" model that can inform measures for mitigating cosmic radiation injury.

Comparison of in situ black-lipped oyster spat collection and larval dispersal modelling results in semi-closed pearl-farming lagoons of the Tuamotu Archipelago.

Spat collection of the pearl oyster Pinctada margaritifera in atoll lagoons of French Polynesia is the fundamental sustain of black pearl farming. Spat collection has always yielded variable results in space and time, but obvious signs of steady decreases, even collapses, have emerged in several lagoons. Spat collection materializes the ecological connectivity pathways between wild spawning populations and the location of artificial larval settlement substrates. To assess if oyster larval dispersal modelling could capture such pathways, we compared four six-week long spat collector deployment periods with dispersal simulations in two different lagoons. Spat collectors displayed wide spatial and temporal variations. Numerical modelling and field experiments were generally not in agreement. Although both methods have limitations, they can still approximate each other. But the accuracy of model simulations cannot be ascertained with spat collection data only. Using a SWOT (Strength-Weakness-Opportunities-Threats) analysis, we emphasize the complementarity of both approaches for management decisions.