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N-Acyl-N-alkysulfonamides (NASAs) can be used to site-selectively label proteins via proximity-mediated reactions. However, the synthesis of NASA probes can be challenging, typically using a two-step synthetic route that relies on alkylation of a weakly nucleophilic acyl-sulfonamide intermediate. Here, we develop a novel one-step strategy for NASA synthesis from a common alkyl-sulfonamide intermediate, overcoming these challenges. A series of NASA probes bearing common labels for protein modification are efficiently synthesized, in a single step, from the corresponding carboxylic acid. This method will increase the accessibility and versatility of these powerful reagents, and the applications of proximity-mediated protein labelling.
Rapid, accurate, and reliable detection of pathogenic bacteria remains a critical need in clinical, food, and environmental monitoring. In today's context, nucleic acid amplification-mediated biosensing have emerged as a prominent approach to improve detection sensitivity, whereas dual-mode signal readout approaches have more enhanced analytical robustness and reliability. This review outlines recent advances in nucleic acid signal amplification strategies, including enzyme-based methods like LAMP, RPA, and RCA, as well as enzyme-free approaches like HCR, CHA, and EDR. Special attention is given to incorporating these amplification methods into dual-mode biosensing systems that combine both optical and electrochemical transduction mechanisms. This integration enables complementary signal generation and improves detection accuracy by reducing false-positive and false-negative results. This study critically examines the advancement of nucleic acid signal amplification strategies (NASAS)-mediated dual-mode sensing systems for detecting major pathogenic bacteria, including Escherichia coli, Salmonella, Listeria monocytogenes, Staphylococcus aureus, and Vibrio species, focusing on selectivity, sensitivity, assay design, and real-sample applicability. Finally, the review highlights present challenges related to system integration, standardization, and point-of-care applications. Additionally, it outlines potential future directions for rendering nucleic acid amplification-based dual-mode probes into practical diagnostic devices. Overall, this study affords a comprehensive synthesis of emerging approaches and design mechanisms for next-generation diagnostic scaffold for pathogen analysis.
This paper introduces a high resolution, machine learning-ready heliophysics dataset derived from NASA's Solar Dynamics Observatory (SDO), specifically designed to advance machine learning (ML) applications in solar physics and space weather forecasting. The dataset includes processed imagery from the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI), spanning a solar cycle from May 2010 to December 2024. To ensure suitability for ML tasks, the data has been preprocessed, including correction of spacecraft roll angles, orbital adjustments, exposure normalization, and degradation compensation. We also provide auxiliary application benchmark datasets complementing the core SDO dataset. These provide benchmark applications for central heliophysics and space weather tasks such as active region segmentation, active region emergence forecasting, coronal field extrapolation, solar flare prediction, solar Extreme Ultraviolet (EUV) spectra prediction, and solar wind speed estimation. By establishing a unified, standardized data collection, this dataset aims to facilitate benchmarking, enhance reproducibility, and accelerate the development of AI-driven models for critical space weather prediction tasks, bridging gaps between solar physics, machine learning, and operational forecasting.
Although lightning activity has been confirmed on Jupiter, Saturn, and Neptune through the detection of lightning-generated electromagnetic waves, its occurrence on Venus and Mars remains unclear. Here, we report observations of such a frequency-dispersed whistler detected in the ionosphere of Mars by NASA's MAVEN spacecraft. We demonstrate the plausibility of wave propagation from the atmosphere to the spacecraft, and we show that the observed dispersion corresponds to theoretical expectations using realistic crustal magnetic field and ionospheric models. Increased attenuation at higher frequencies explains why only the low-frequency part of the whistler is observed. Our observations provide direct evidence of electromagnetic waves from an impulsive source on Mars, suggesting that electric discharges may indeed occur in the Martian atmosphere.
NASA identifies spaceflight-associated neuro-ocular syndrome (SANS) as a significant health concern for astronauts on missions exceeding 30 d. This retrospective analysis evaluates age, mission duration, and preflight bodyweight as risk factors for hyperopic shift, a component of SANS. Results may guide the development of prevention strategies for future missions and provide insight into similar conditions on Earth. Deidentified data were obtained from NASA' s Medical Evaluation Documents, Volume B database for astronauts who participated in space missions >30 d. Refractive outcomes were assessed using manifest refraction (MR) and manifest refraction spherical equivalent (MRSE), calculating the mean change between pre- and postflight measurements across both eyes. The cohort included 85 subjects for age and mission duration analyses and 84 for bodyweight. Each risk factor was divided into quintiles. Spearman's rank correlation identified associations between quintiles and hyperopic shift. Age showed a significant positive correlation with hyperopic shift (MR: r = 0.373; MRSE: r = 0.353). Mission duration correlated with MR (r = 0.253) and showed a nonsignificant trend with MRSE (r = 0.195). Preflight bodyweight correlated significantly with MRSE (r = 0.242) and showed a similar nonsignificant trend with MR (r = 0.207). Age was the strongest predictor of hyperopic shift. Mission duration and bodyweight showed weaker positive associations. Future investigations should define SANS with threshold criteria and use logistic regression. The relationship between these risk factors and other manifestations of SANS also warrants further investigation. Aldeghi TM, Higbee RG. Identifying predisposing factors for hyperopic shift in long-duration spaceflight. Aerosp Med Hum Perform. 2026; 97(8):627-632.
The observation of the lunar crescent is significant in astronomy, cultural traditions, and religious lunar calendar determinations. However, earth-based imaging that captures all lunar phases, particularly the new crescent across multiple months, remains limited. This study explores the feasibility of using artificial intelligence (AI) techniques to detect and analyze the birth of the new lunar crescent using space-borne imagery from NASA's Lunar Reconnaissance Orbiter (LRO), spanning over 13 years. This study evaluates both deep learning and traditional machine learning approaches for new crescent detection. Convolutional Neural Networks (CNN), Random Forests (RF), and Support Vector Machines (SVM) were applied to orbital lunar images. A custom image preprocessing pipeline was implemented, including grayscale conversion, contrast-limited adaptive histogram equalization, and noise reduction. The CNN architecture was further enhanced by integrating lunar imagery with moon age data. Experiments were conducted using a temporally split dataset to simulate real-world conditions. Model robustness was also evaluated using synthetically generated noise and occlusion. The experimental results demonstrated high performance across all evaluated models, achieving precision, recall, F-score, and overall accuracy of approximately 98%. Among the tested approaches, RF and CNN models produced the best overall performance, outperforming SVM. The CNN model showed strong robustness under degraded image conditions, maintaining high accuracy when subjected to Gaussian noise and image occlusions of up to 50%. The findings indicate that AI-based techniques, particularly CNN and RF models, are effective for detecting the new lunar crescent from orbital imagery. The robustness of the CNN model suggests practical applicability in real-world lunar observation scenarios. This study contributes toward supporting traditional crescent identification methods and offers potential solutions for reducing calendar discrepancies across different regions.
NASA's Goddard Earth Observing System (GEOS) infrastructure was used to couple a cloud-admitting (7-km grid, 72 levels) configuration of the GEOS atmospheric model with a mesoscale-resolving (2-4-km grid, 90 levels) Estimating the Circulation and Climate of the Ocean (ECCO) configuration of the Massachusetts Institute of Technology general circulation model (MITgcm), and to conduct a 14-month "nature" simulation initialized with January 20, 2020, 21Z conditions. The output of this simulation is contained in the dataset described here. The NASA GEOS/ECCO Coupled Nature Run includes astronomical tidal forcing in the ocean component of the simulation, an interactive aerosol component and aerosol-cloud interactions in the atmosphere, and the storage of copious amounts of model output. The inclusion of tidal forcing permits a more realistic representation of vertical mixing in the ocean and of high-frequency variability that is aliased in satellite observations. All of the above make this simulation well suited as a nature run in Observing System Simulation Experiments (OSSEs) and for the study of high frequency/wavenumber coupled processes in weather and climate.
NASA's ICESat-2 mission was launched in 2018, carrying a photon-counting laser altimeter, with a primary objective of measuring height changes across Earth's surface. ICESat-2 has provided measurements of ice surface height between 88º N and S, repeated four times per year, with high vertical accuracy and along-track spatial resolution. Its accuracy and coverage has enabled near-complete recovery of height changes across the ice sheets, capturing subtle changes in the interior, and rapid changes along the dynamic margins with steep slopes and the floating peripheral ice shelves. The ICESat-2 Science Team has developed a suite of algorithms that produce along-track and gridded land ice height products at various levels of processing, all freely available at the National Snow and Ice Data Center. Here, we describe three higher-level land-ice data products derived from ATL06 and their underlying algorithms: along-track height change (ATL11), digital elevation model (ATL14) and gridded surface height change (ATL15). We demonstrate the suitability of each data product for studying different ice sheet regions. We then show height changes for Greenland and Antarctica from ATL15 during the first 6 years of the ICESat-2 mission (October 2018-December 2024), illustrating how ICESat-2 measurements can distinguish the multi-year trends from seasonal fluctuations.
Detection of organic molecules on Mars is challenging due to a variety of degradation processes occurring at the Martian surface, including UV irradiation. Nevertheless, the NASA's Curiosity rover found evidence of organic molecules in clays, suggesting that these minerals might be particularly suitable to preserve organics on Mars. In this work, the photostability of L-histidine adsorbed at different pHs on nontronite under Martian-like UV irradiation was investigated in order to assess the preservation potential of this clay in the Martian environment. The interactions between L-histidine and nontronite were investigated via Infrared spectroscopy and X-Ray Diffraction, in order to understand the possible preservation mechanisms. Results indicate that L-histidine intercalates into the mineral interlayer at acidic pH, and undergoes minor degradation after UV exposure compared to the pure molecule. At basic pH, polymolecular layers are formed and no degradation is observed. These results show that nontronite acts as a photoprotective mineral for L-histidine both at acidic and basic pH, making it a suitable mineral target for organic detection on Mars.
IntroductionExposure to spaceflight and microgravity environments has been implicated in large reductions in astronaut bone mineral density (BMD). While low BMD is a known risk factor for fracture, there have been no reported cases of in-flight fracture, and very little documentation of post-flight fracture. The present study sought to review the incidence of fractures within 5 years of return to spaceflight.MethodsUsing NASA's Lifetime Surveillance of Astronaut Health epidemiology database, a retrospective cohort study was conducted to identify the incidence of fracture in the 5-year post-flight period. All astronauts who participated in spaceflight with 5-year post-flight medical data were included. Demographics were compared between the fracture and nonfracture cohorts.ResultsOf the 242 astronauts who met the inclusion criteria, 7 (2.9%) sustained fractures within 5 years post-flight. Three post-flight fractures occurred in the hip or spine. Six of the 7 fractures occurred within 2 years of return from spaceflight. Spaceflight length, age, and time from spaceflight were not statistically significantly associated with increased risk of fracture.ConclusionFracture upon return to the gravitational environment is a serious risk for astronauts that can significantly jeopardize astronaut health and mission success. Fractures of the hip and spine, specifically, are associated with decreased BMD. While the incidence of these fractures is roughly 1%, the negative implications, including high 1-year mortality rates and functional implications, emphasize the need to optimize bone health and fracture treatment protocols.
The combustion of solid waste remains an understudied global challenge due to difficulty in monitoring these types of fires. Furthermore, the health and environmental impacts of waste fires are disproportionately felt by rural and Indigenous communities. To address this gap, we characterized fires at landfills, unregulated disposal sites, and recycling facilities using NASA's Fire Information for Resource Management System (FIRMS) and high spatial-temporal-resolution satellite imagery from PlanetScope for 2019-2024; we also evaluated spatial and temporal increases in particulate matter (PM) concentrations concurrent with fire events and IoT ground sensing systems in a complementary approach. Results indicated that 35% of identified fires were detected by FIRMS, 52% by PlanetScope products, and elevated PM2.5 levels were observed during 37% of fires. VIIRS instruments account for a majority of detections. Across detections, brightness temperature ranged from 295.4-367.0 K and fire radiative power (FRP) ranged from 0.3-376.3 W. A general increase in detections is seen after 2017-2018, concurrent with geopolitical trends, climate change, and changes in waste composition that increase risk of waste-fire. These findings demonstrate the potential utility of remote sensing data products for the surveillance of waste fires, thereby enhancing capacity to address the health and environmental impacts of these events. Notably, this is the first study emphasizing surveillance of unregulated disposal site fires in the American waste stream.
Blue Ghost data suggest NASA's growing commercial Moon program can deliver results.
The IMAP-Hi Energetic Neutral Atom (ENA) Imager on NASA's Interstellar Mapping and Acceleration Probe (IMAP) mission (McComas et al. 2018a, 2025) is designed to measure ENAs from the global interaction between the heliosphere and the local interstellar medium (LISM). These ENAs are initially plasma ions of solar wind origin that are neutralized by charge exchange with the cold neutral atoms of LISM that freely flow through the heliosphere-LISM interaction region. IMAP-Hi consists of two identical single-pixel sensors, each covering the ENA spectral range from 0.44 keV to 15.6 keV over nine contiguous energy passbands and having an approximately conical field-of-view (FOV) of 4.1o full width at half maximum (FWHM). The Hi-45 sensor points 45o relative to the spacecraft spin axis from the antisunward direction; each spacecraft spin, it measures ENA intensity over a circular swath with half-cone angle 45o centered on the ecliptic plane. The Hi-90 sensor points 90o relative to the spin axis; each spacecraft spin, it measures ENA intensity over a great circle in the sky, sampling both the north and south ecliptic poles. As the IMAP spin vector is re-pointed daily toward the Sun, the ecliptic longitude of the swaths moves daily by ∼1o such that a full sky map is acquired by Hi-90 every six months and a complete low latitude (-45o to +45o) map is acquired by Hi-45 annually. The IMAP-Hi sensor design has direct heritage from the IBEX-Hi imager on the Interstellar Boundary Explorer (IBEX) mission, with substantial improvements in energy range, energy resolution, angular resolution, signal-to-noise ratio, and, for ecliptic latitudes within ±45o, temporal resolution and exposure time. The global ENA maps acquired by IMAP-Hi partially overlap in energy and viewing with the ENA maps acquired by the IMAP-Lo and IMAP-Ultra ENA imagers, which we combine to answer fundamental questions about the structure and dynamics of the interaction of the heliosphere and the LISM.
The difference between the ice and water pressures, or the effective pressure, influences water flow and sliding at the ice-bed interface. Effective pressure is typically quantified with subglacial hydrology models because direct measurements of the subglacial environment are sparse. Active subglacial lakes provide an opportunity to constrain effective pressures with altimetry because subglacial water-volume changes manifest at the ice-sheet surface as elevation-change anomalies. Here, we develop a method for estimating effective pressures from altimetry data above active subglacial lakes. We synthesise a previous theory of subglacial lake effective pressure with an altimetry-based inverse method that relates elevation-change data to water-volume changes. We apply the method to elevation-change data from NASA's ICESat-2 satellite altimetry mission over several active lakes in Antarctica. We find that deviations from flotation (zero effective pressure) are typically a negligible fraction of the overburden (e.g., 10 kPa), although larger deviations can arise when the ice viscosity is large. For example, effective pressures over subglacial lake Byrds10 in East Antarctica locally reached magnitudes on the order of the tensile strength of glacier ice (e.g., over 100 kPa). These effective pressure estimates can constrain subglacial hydrology models in regions with active subglacial lakes and provide new insights into glacier-bed dynamics.
The translocation of molecules through nanoscale pores is ubiquitous in biology and widely used in biotechnology for nanopore sequencing and characterizing single biological molecules. Numerous artificial channels mimicking biological pores have been developed, and one of those is a single-walled carbon nanotube porin (CNTP) embedded in a lipid bilayer membrane. Although transport of ssDNA through CNTP has been demonstrated experimentally, protein translocation through CNTP has rarely been achieved. Here, we report the experimental observations of protein (cytochrome c) translocation through a single-walled carbon nanotube of an inner diameter of ∼1.3 nm embedded in a lipid bilayer membrane without using any chemical denaturant, enzyme motor, or tagging with an oligonucleotide. The electric field was found to sufficiently unfold the cytochrome c protein to facilitate the translocation, as confirmed by a decrease in the average residence time of the protein at the CNTP upon increasing the transmembrane potential. A simple free energy model suggests that the relatively fast (microseconds) dynamic interconversions of protein conformational states appear to dictate the slow (∼100 ms) translocation and account for the observed voltage-dependent rate constants from the exponential residence time distributions. Our report on the experimental evidence of protein translocation through CNTP may open the opportunity to explore the applications of CNTP in targeted protein delivery, in nanopore proteomics, and probing protein conformational transitions at the single-molecule level.
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Evidence suggests the persistence of non-spore-forming Acinetobacter johnsonii in high-stakes controlled and nutrient-limited environments. Here, we investigated the mechanisms underlying this adaptability through a comprehensive genomic analysis of 22 isolates of A. johnsonii from NASA's Payload Hazardous Servicing Facility (PHSF) and one carbapenem-resistant strain (E154408A) from patient colonization in Ireland. Core-genome phylogeny revealed clustering of PHSF-originating isolates in a monophyletic clade divergent from the main species lineage. Species-wide virulence-associated genes and metabolic reconstruction indicated the exclusive presence in PHSF-originating isolates of two complete efflux pumps and a conserved allantoin racemase, suggesting adaptability for multiple environmental stresses. The ubiquity of blaOXA in genomes analyzed (n = 112) and the phenotypically validated multidrug-resistant profile of the E154408A strain highlight A. johnsonii's potential as an antimicrobial resistance (AMR) reservoir. Plasmidome analysis suggested gain/loss events across the monophyletic population and potential AMR acquisition pathways. Genome-to-metagenome mapping identified genomic signatures of A. johnsonii in PHSF >10 years post-initial isolation.IMPORTANCEAcinetobacter johnsonii is increasingly recognized as an emerging human pathogen, with growing evidence of its ability to persist in controlled, high-stakes environments, posing risks as both a persistent environmental contaminant and an antimicrobial resistance (AMR) reservoir. Yet, gaps remain in our understanding of its AMR profile and the mechanisms that enable its enhanced environmental adaptability. This knowledge is necessary in contexts where biological cleanliness is a priority, such as clinical settings and spacecraft assembly facilities' cleanrooms, where contamination of hardware with terrestrial microorganisms is concerning. In this study, we aim to address some of the key knowledge gaps by providing genomic insights into a rare multidrug-resistant clinical isolate and 22 NASA cleanroom isolates that persisted for over a decade in extremely clean conditions. Our findings will help assess the contamination risk of A. johnsonii in high-stakes environments and ultimately strengthen our ability to manage this microbial contaminant across terrestrial and extraterrestrial settings.Cleanroom-derived A. johnsonii genomes show traits consistent with increased adaptability.Genomic signatures of A. johnsonii persisted in the cleanrooms for over 10 years.blaOXA is ubiquitously found in all 112 A. johnsonii genomes analyzed.Isolate E154408A is the first reported patient colonization case by carbapenem-resistant A. johnsonii in Europe.
NASA's OSIRIS-REx mission demonstrated the potential for robotic spacecraft to probe physical properties of planetary bodies. In 2020, the spacecraft autonomously collected granular material from Bennu, a small unconsolidated asteroid, leaving behind a region excavated by the combined effects of the gas-driven sampler and backaway thrusters. Disambiguating the physical responses to these two energy-injection events offers an opportunity to characterize a microgravity asteroid's near-surface properties and understand how thruster-surface interactions could be utilized by future missions. We do so here using data from the spacecraft's instruments and telemetry in conjunction with detailed modeling of the thrusters. The sampler initially formed a crater 0.5-0.7 meters in radius before thruster activation. The thrusters deposited four regions of high-pressure gas ∼1-6 meters from the contact location, with lower pressures inside and beyond this region. As a result, the crater expanded into a region undergoing active erosion from the thrusters, and its final dimensions were increased by thruster effects. The total erosion and redeposition depend on the pre-existing mass distribution and topography of the area. Varying erosion responses to the thrusters indicate variability in material properties laterally, and, combined with accelerometer data, as a function of depth. The efficacy of the thrusters to mobilize material over a broad area (>100 square meters), and at very small pressures (perhaps as low as 0.005 Pa), motivates their use to interrogate small-body surface properties, particularly in the spacecraft's planned 2029 encounter with asteroid Apophis. The online version contains supplementary material available at 10.1007/s11214-026-01285-8.
In 2024, NASA's Perseverance rover explored Neretva Vallis, an ancient river channel that once transported water into Jezero crater. There, the rover encountered Mg-poor mudstones with diverse alteration features. In 32 rock targets in Neretva Vallis, nickel (Ni) was detected by the SuperCam instrument with concentrations in individual rocks as high as ~1.1 weight percent - the highest abundance ever seen in bedrock on Mars. In this work, we describe and contextualize these Ni enrichments using outcrop-scale imagery and petrographic-scale elemental maps provided by the PIXL instrument. We find Ni enrichment in Fe-sulfides and their weathering products. The geochemistry and morphology of Neretva Vallis Fe-sulfides are similar to pyrite present in terrestrial Archean and Paleoproterozoic sedimentary rocks. As an essential element for terrestrial microbial life, the proximity of Ni enrichments to reduced sulfur and organic matter adds to the interest in bringing back to Earth the rock sample collected by Perseverance at this location, which could provide key insights into complex redox chemistry on early Mars.