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Recent reports indicate a new concept of low-dose ionising radiation cataractogenesis. In 2020, a two-stage aetiology of initiation and maturation was proposed by Richardson and colleagues for posterior subcapsular cataract (PSC) and perhaps cortical cataract development. The mechanisms involve various oxidative stress and biochemical factors, some of which are relevant to A-bomb survivors, such as ocular ion imbalance, inflammation, and maybe oxygen level changes. An example of a known, specific cataractogen is hypoparathyroidism and associated hypocalcaemia. However, a recent report indicated calcium overload in situ is also a cataractogen. In fact, Neriishi and colleagues in 2003 reported a preliminary analysis of the serum in A-bomb survivors, finding persistent inflammation and calcium levels that were statistically significant as indirect systemic effects in the dose response of PSC and cortical cataract. Therefore, the above reports linking cataractogenesis to 'intermediate variables' and perhaps insulin resistance strongly support the preliminary results in A-bomb survivors. US astronauts display similar excess cataracts and serum-derived biomarkers. Thus, further analyses of updated datasets from A-bomb survivors and astronauts allowing for these intermediate risk factors and retinal/uveal pathologies are required to test these new concepts in ionising radiation cataractogenesis.

Long-term microgravity disrupts astronauts' intestinal homeostasis, causing gut dysbiosis, barrier injury and immune imbalance among other issues. Vitamin D (VD) and probiotics may provide synergistic protection, but their synchronous and stable gastrointestinal delivery remains a key challenge. In this study, zein and sodium caseinate (NaCas) were used as wall materials to fabricate Vitamin D3 (VD3)-loaded nanoparticles (ZND) by anti-solvent precipitation. ZND and Lactobacillus rhamnosus GG (LGG) were then co-encapsulated into microcapsules (ZND-loaded LGG microcapsules, ZND-L) via complex coacervation. ZND-L showed favorable physicochemical properties, good storage stability, high encapsulation efficiency, and high probiotic viability retention. It also exhibited gastrointestinal-environment-adaptive controlled release behavior. The microcapsules shell protected VD3 and LGG against acidic and bile-related stresses, reduced premature release under simulated gastric conditions, and enabled sustained release under simulated intestinal conditions. This design promoted distal intestinal delivery of bioactive VD3 and viable LGG. In the tail-suspension simulated microgravity rat model, ZND-L mitigated intestinal dysbiosis, restored intestinal barrier function by upregulating the expression of occludin (OCC), zonula occludens-1 (ZO-1) and secretory immunoglobulin A (sIgA), and further reshaped systemic immune homeostasis by reducing the production of pro-inflammatory cytokines. These benefits were associated with coordinated microbiota-barrier-immune regulation and improved VD3 metabolic signaling through activation of the vitamin D receptor (VDR) pathway. The combined microcapsules intervention outperformed single VD3 supplementation and administration of free LGG. It offers a promising strategy for maintaining intestinal health in microgravity environments and has the potential for application in the field of aerospace nutrition.

To enhance understanding of the biotoxicity of inhaled lunar dust (LD) and safeguard astronaut health during future crewed lunar missions, we performed coarse-grained molecular dynamics simulations of nine silica nanoparticle (SiNP) aggregates─the primary component of LD─varying in size (3 and 6 nm), shape (sphere, ellipsoid, and cube), and surface features (0, 1, and 3 bulges) interacting with a pulmonary surfactant (PS) monolayer. The key findings are (1) shape, not size, governs aggregate architecture and fate: cubic SiNPs yield the most aspherical, rapidly forming aggregates and switch translocation from penetration to embedding when present as 6 nm members, and aggregation time scales as cube > ellipsoid > sphere. (2) Aggregates induce greater PS disturbance than equal-volume single SiNP, and the DPPC order parameter Sz falls to 0.678-0.706 and is driven lower (0.587-0.720) when nonspherical SiNPs dominate the aggregates. (3) Surface bulges normally hinder translocation, yet once their size and number exceed a threshold, they locally rupture the PS monolayer and shorten translocation while still increasing PS adsorption and Sz. These findings establish that aggregate morphology, rather than mass, exacerbates PS monolayer disturbance and provide quantitative benchmarks for guiding dust-mitigation strategies for future lunar missions.

This study investigated the long-term neurobehavioral and physiological impacts of low-dose helium (4He) ion exposure-a key component of galactic cosmic radiation-on male Long Evans rats. After training on the rodent psychomotor vigilance test (rPVT), the rats were irradiated and monitored for up to 180 days to assess sustained attention and social recognition memory, alongside blood and bone analyses. Results showed that acute exposure to 25 cGy 4He ions significantly impaired sustained attention, increasing attention lapses and reaction times, and decreasing task accuracy. Exposure to 5 cGy only affected specific reaction time measures. However, both doses caused persistent social recognition memory impairments for 180 days. While overall bone mechanics remained largely unchanged, specific skeletal strength parameters were affected. Importantly, significant correlations emerged between behavioral performance and circulating cytokines (IL-1beta), undercarboxylated osteocalcin (ucOC), and bone biomechanics. This suggests these blood and bone targets could serve as diagnostic biomarkers for radiation-induced neurobehavioral deficits. The sustained and progressive nature of the neurobehavioral deficits observed underscores the critical need for effective countermeasures to protect astronaut health and performance during exploration-class missions.

Spaceflight-associated neuro-ocular syndrome (SANS) poses significant ocular health risks in long-duration missions, yet its molecular mechanisms remain incompletely understood. Oxidative stress and apoptosis are candidate drivers, but their transcriptomic-phenotypic relationships in spaceflight-exposed retinal tissue have not been systematically characterized. We applied a machine learning ensemble to predict two ocular phenotypes: 4-hydroxynonenal (4-HNE) endothelial cell density as a marker of oxidative damage, and TUNEL endothelial cell density as a marker of apoptosis. In this observational study, we use transcriptomic data from a controlled experiment with ground control and spaceflown mice to predict these phenotypes. Gene Ontology pathway enrichment was performed using the most predictive genes for each phenotype. Genes predicting 4-HNE converge on membrane-associated pathways, photoreceptor modification, synaptic dysfunction, and extracellular matrix dysregulation, including B2m, Trf, Cnga1, mt-Nd1, Snap25, and Efemp1. Genes predicting TUNEL emphasize stress-induced apoptosis, rod photoreceptor degeneration, and endoplasmic reticulum dysfunction, with Ddit4, Nrl, Rom1, Reep6, and Gabarapl1 emerging as central regulators. Oxidative lipid peroxidation and apoptotic cell death represent complementary and molecularly distinct pathological mechanisms in spaceflight-exposed murine retinal tissue. The gene signatures provide a putative molecular framework for developing noninvasive biomarkers and therapeutic targets to monitor and protect astronaut visual health during long-duration and deep-space missions.

Astronauts consistently exhibit slower movements in microgravity, even during tasks requiring rapid responses. The sensorimotor mechanisms underlying this general slowing remain debated. Two hypotheses have been proposed: either the sensorimotor system adopts a conservative control strategy for safety and postural stability, or the system underestimates body mass due to reduced inputs from proprioceptive receptors. To dissociate these opinions, we studied 12 taikonauts aboard the China Space Station performing a classical hand-reaching task. Compared to their pre-flight performance and to an age-matched control group, participants showed increased movement durations and altered kinematic profiles in microgravity. Model-based analyses of motor control parameters revealed that these changes stemmed from reduced initial force generation in the feedforward control phase followed by compensatory feedback-based corrections. These findings provide support for the body mass underestimation hypothesis while being inconsistent with the strategic slowing hypothesis. Importantly, the sensory estimate of bodily property in microgravity is biased but immune from sensorimotor adaptation, calling for an extension of existing theories of motor learning.

Hypogravity environments (e.g., 1/6 g on the Moon and 3/8 g on Mars, where gravity is lower than on Earth) profoundly alter the sensorimotor mechanisms underlying spatial orientation, perception, and manual task execution. Understanding these adaptations is essential for ensuring astronaut operational performance. In particular, there is a need for a better understanding of the long-term effects of hypogravity on manual task performance during seated operations, such as piloting, landing, and navigating, which rely on the integration of vestibular, visual, and somatosensory signals that drive motor adaptation in unfamiliar gravitational environments. However, sensorimotor processes and adaptation to hypogravity remain incompletely understood, particularly after prolonged exposure. This perspective paper synthesizes current knowledge largely derived from experimental platforms with inherent constraints. Additionally, it explores the convergence of technological approaches used both to simulate hypogravity for spaceflight preparation and to support rehabilitation after vestibular or neurological impairment. Finally, it suggests that future research should focus on long-term hypogravity simulation using AI-driven assistive technologies through interdisciplinary collaboration.

Long-duration spaceflight elicits spinal impairments, including bone loss and intervertebral disc degeneration (IVDD). As the connective hub of the entire spine, the intervertebral disc (IVD) plays a pivotal role in maintaining spinal stability. However, the molecular mechanisms through which space microgravity mediates IVDD remain elusive, and the core spinal component responsible for mechanical load-bearing and the maintenance of spinal mechanical homeostasis has not been identified. Herein, we identified for the first time that space microgravity induces nucleus pulposus (NP) degeneration via PIEZO1. Analysis of samples from patients with IVDD indicates downregulated PIEZO1 expression in NP cells. Specific Piezo1 deficiency in NP cells not only disrupts the extracellular matrix (ECM) metabolism of NP but also impairs the homeostasis of the annulus fibrosus and cartilage endplate. Mechanistically, Piezo1 deficiency drives NP cell apoptosis and alters their secretory profile by activating the AMP-activated protein kinase (AMPK) signaling pathway, thereby mediating functional spinal unit (FSU) dysfunction through paracrine regulation. Targeted delivery of AMPK inhibitors to NP tissue markedly mitigates the progression of IVDD induced by mechanical instability. Together, our findings uncover the central role of the NP in mechanical response and its paracrine function within the FSU for the first time, providing a potential therapeutic strategy for IVDD treatment and astronaut spinal protection.

Accurate attitude estimation for highly dynamic spacecraft relies on robust fusion of star-tracker and inertial measurements. However, asynchronous sensing, motion blur in star images, and delayed star-tracker outputs can significantly degrade estimation accuracy and temporal consistency. To address these challenges, this paper proposes a dual-layer factor graph optimization framework for asynchronous star-tracker/IMU fusion under highly dynamic conditions. At the lower layer, high-rate IMU measurements are combined with motion-blurred star streak observations to construct a local factor graph over the exposure interval. The proposed local fusion process reconstructs discrete star-trail points, estimates angular velocity, and selects IMU-aligned representative observations for temporally consistent association of blurred star measurements. At the upper layer, delayed attitude constraints, propagated star-vector information, and inertial rotational constraints are jointly incorporated to refine the attitude trajectory. Simulation and semi-physical experimental results demonstrate that the proposed framework achieves higher estimation accuracy, stronger robustness, and better tolerance to delayed or intermittent star-tracker observations than the comparison methods, while maintaining practical computational efficiency for near-real-time onboard implementation.

The seismic performance of vertical reinforcement discontinuous splice prefabricated shear walls (SGBL prefabricated shear walls) in high-rise buildings is investigated in this study. The failure mechanisms, load-bearing capacity, ductility, and energy dissipation characteristics of these walls are clarified, with particular attention given to the influence of the shear-span ratio and axial compression ratio. A refined model was established using ABAQUS finite element software, and simulations were conducted on individual SGBL wall panels under various shear-span ratios (achieved by adjusting story heights) and axial compression ratios (0.1, 0.3, 0.5). The results demonstrate that the load-bearing capacity of the wall panels increases significantly with the axial compression ratio (Specimens with shear-span ratios of 1.25, 1.5, and 1.75 exhibited increases of 76.8%, 88%, and 82%, respectively). In contrast, ductility and energy dissipation capacity are reduced. When an axial ratio of 0.5 and a shear-span ratio of 1.25 were applied, interlaced diagonal cracks were observed in specimen SW1-0.5. Therefore, the inclusion of inclined reinforcement is recommended in practice to prevent premature brittle failures. Under a constant axial compression ratio, it was found that the load-bearing capacity decreases as the shear-span ratio increases, whereas ductility and energy dissipation capacity are enhanced. Specimen SW3-0.1, characterized by a low axial compression ratio and a large shear-span ratio, exhibited the optimum energy dissipation capacity and ductility. During the simulation, no vertical cracks were observed at the joint interface between the precast panels and the cast-in-situ components, confirming that the structure exhibits excellent integrity and compatibility.

Phase engineering has proved effective in enhancing electrocatalytic performance by precisely controlling crystal structures. While significant efforts have been dedicated to phase regulation of active metals, the role of crystal phase of catalyst supports in steering the hydrogen migration during hydrogen evolution reaction (HER) remains underexplored. This work systematically investigates zirconium dioxide in its monoclinic (m-ZrO2) and tetragonal (t-ZrO2) phases as supports for Ru nanoclusters. A combination of spectroscopy and theoretical calculation demonstrates strong electronic metal-support interactions and work function difference between Ru and m-ZrO2 lead to interfacial charge accumulation, accelerated water dissociation, and reverse hydrogen spillover, significantly enhancing electrocatalytic HER performance in alkaline medium. The Ru@m-ZrO2/C catalyst exhibits excellent HER activity in different electrolytes. It achieves 10 mA cm-2 with an extremely low overpotential (η10) of only 28 mV in 1 M KOH, delivering a mass activity of 2.72 A mgRu-1 (at 50 mV overpotential), which is 45 times higher than that of commercial Pt/C. The η10 values are 56, 42, and 30 mV in 0.5 M H2SO4, 1 M KOH + 2 M NaCl, and 1 M KOH + simulated seawater, respectively. Furthermore, the catalyst also demonstrates excellent stability under alkaline simulated seawater electrolysis conditions. When integrated into an anion-exchange membrane water electrolyzer, it achieves 1.0 A cm-2 at 1.76 V with stability exceeding 300 h. This work underscores the pivotal importance of support phase engineering for designing high-performance electrocatalysts for water splitting.

As coronavirus disease 2019 (COVID-19) has transitioned into an endemic phase characterized by sustained transmission and widespread hybrid immunity, understanding region-specific determinants of severe disease remains important for real-world risk stratification and public health planning. A retrospective surveillance study was conducted using 5,072 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) whole-genome sequences linked to clinical metadata from 13 cities in Jiangsu Province (from January 2023 to December 2024). Features derived from clinical, viral genomic, and regional epidemiological domains were evaluated using five machine learning models and assessed on an independent 2024 cohort. Model interpretability was examined using SHapley Additive exPlanations (SHAP) analysis. Key mutations were further examined through epitope prediction, peptide-HLA docking and binding affinity assessments to explore potential immunological implications. Integrated multidimensional features demonstrated superior predictive performance compared with single-domain inputs. In the independent 2024 validation cohort, LightGBM achieved the best overall performance (F1-score = 0.603; AUC = 0.735). SHAP analysis identified age as the dominant model predictor, followed by the age-viral load interaction, regional location, vaccination status, and selected viral genomic features. Epitope prediction and structural analyses suggested L452W-associated changes in predicted peptide-HLA interaction patterns within the evaluated set of high-frequency HLA class I alleles in the Jiangsu population, providing candidate hypotheses for future experimental validation. COVID-19 severity during the endemic phase appeared to reflect interactions among host susceptibility, viral genetic variation, and regional epidemiological context, with age and vaccination emerging as key predictive factors. This population-based, interpretable framework highlights clinically relevant risk-associated features and may support real-world risk stratification in ongoing and future infectious disease surveillance.

The study of interfacial fluxes under evaporative or condensation processes is ubiquitous in thermal systems, propulsion devices, and many other engineering applications. Most continuum-scale models fail to capture the true nature of thermodynamic property variation across the interface, particularly under high-temperature and high-pressure conditions. An improvement over the sharp interface assumption of such continuum-scale models is the consideration of a diffused interface and using kinetic boundary conditions (KBCs) to model mass transport across the liquid-vapor interface. Prior studies on KBCs mainly address monatomic fluids. Two of the main ingredients required to form KBCs are density and mass flux. Here, we study a Type-III binary mixture of n-dodecane and nitrogen using non-equilibrium molecular dynamics at near-critical temperatures. Interfacial properties such as thickness, density gradient, and surface tension were analyzed. A key result is the temporal evolution of the evaporation and reflected mass fluxes across the vapor-liquid interface. We observe that both the evaporation and reflection fluxes increase with increasing temperature, indicating enhanced molecular activity and mass transport across the interface at higher Tr. In contrast, the evaporation coefficient αevap decreases from about α ≈ 0.978 at Tr = 0.70 to α ≈ 0.905 at Tr = 0.95 because the reflected-out flux increases along with the evaporation flux, which reduces the net efficiency of molecular evaporation across the interface. To the authors' knowledge, this is one of the very few studies estimating mass transport coefficients for Type-III binary systems, laying the foundation for KBCs in hydrocarbon/nitrogen mixtures.

Betalains are nitrogen-containing pigments that produce red-violet and yellow-orange coloration in plants of the order Caryophyllales. Owing to their antioxidant, anti-inflammatory and anticancer activities, they have attracted considerable interest as natural food colourants and functional ingredients. Betalain biosynthesis is governed by both developmental programmes and environmental inputs, among which light quality and jasmonate signalling are key regulators. This review systematically examines the independent and synergistic roles of these two signals in controlling betalain production. Exogenous methyl jasmonate (MeJA), a widely used elicitor, is converted intracellularly to the bioactive ligand JA-Ile, which triggers SCF(COI1)-dependent degradation of JAZ repressors, thereby releasing MYC2 and MYC3 to activate downstream transcription. Light quality, operating through specific photoreceptors and the COP1-HY5 module, modulates betalain accumulation in a wavelength- and species-specific manner. Accumulating evidence suggests that both pathways converge on R2R3-MYB transcription factors, which bind MBS motifs in the promoters of the key structural genes CYP76AD1 and DODA. The betalain biosynthetic pathway proceeds through four principal enzymatic steps to yield betacyanins and betaxanthins, catalysed sequentially by ADH, CYP76AD1, DODA and cDOPA5GT. We propose a MYC2-HY5-MYB regulatory axis as a working model for the coordinate regulation of betalain biosynthesis, and identify key questions that remain to be resolved through functional studies in betalain-producing species.

Regulating crystal orientation is a powerful strategy for enhancing the optoelectronic performance of perovskite solar cells (PSCs). However, most existing approaches rely on single-site ligand binding, which not only forms insulating layers that hinder charge transport but also involves weak coordination that limits orientation control. Here, we report a holistic strategy based on a dual-site-binding ligand, dithiopyr, that simultaneously modulates nucleation kinetics, crystal orientation, defect passivation, and charge transport in perovskite films. By coordinating its dual thioester functionalities with adjacent Pb2+ defect sites, dithiopyr effectively relieves lattice strain and promotes a preferential (100) orientation, thereby facilitating efficient charge transport. As a result, the inverted PSCs achieve power conversion efficiencies of 26.90% (certified 26.14%) (1.55 eV), 22.02% (1.25 eV), and 23.11% (1.68 eV), respectively. Notably, large-area modules (30 × 30 cm2) deliver an efficiency of 21.28%, which is among the highest values reported for inverted perovskite solar cells. Unencapsulated devices retain 93.1% of their initial efficiency after 3600 h under ambient conditions and maintain over 95% of their initial performance after 1100 h of maximum power point tracking. This work establishes dithiopyr as a versatile and robust platform for precise crystal orientation control toward high-performance perovskite photovoltaics.

This study presents an experimental and numerical investigation on the impact of embedded fiber optic sensors on the mechanical properties, like tensile, compression, bending and compression-after-impact properties, and sensing performances of intelligent composites. The influence by different volume fractions of embedded fiber optics on the mechanical properties was revealed. Combined with finite element simulations, the effect of embedded sensors on the basic mechanical properties of composite materials was obtained. The sensing performance of the embedded fiber Bragg grating (FBG) sensors was validated through comparison with conventional strain gauges.

Lithium-carbon dioxide batteries (Li-CO2), featuring a high discharge voltage (∼2.8 V) and a high theoretical energy density (1876 Wh kg- 1), have garnered significant attention for their dual capability in energy storage and CO2 fixation. However, the complex reaction pathways across multiphase interfaces and sluggish discharge-charge kinetics result in poor reversibility, which severely hinders their practical application. Addressing these challenges necessitates the development of efficient cathode catalysts, whose activity is fundamentally governed by their electronic structure. In this review, we systematically elucidate the structure-performance-mechanism relationships of cathode catalysts in Li-CO2 batteries by first examining the underlying reaction mechanisms at the electrode-electrolyte interface. We then provide a detailed analysis of how the electronic structures of heterogeneous catalysts influence discharge-charge processes. Particular emphasis is placed on specific electronic structure modulation methods or their combinations, through strategies targeting active sites, surface morphology, and interface structure, as a pivotal route for constructing high-performance catalysts. Subsequently, we also discuss the underlying atomic-level origins of these modulation effects. Finally, we propose several future research directions aimed at advancing the fundamental understanding of Li-CO2 electrochemistry, optimizing electrocatalytic performance, and accelerating the practical implementation of Li-CO2 batteries.

Graphite anodes are limited by low capacity and instability. Conversion-type transition metal sulfides (TMSs) offer high energy density, yet single-component TMSs suffer from rapid capacity decay owing to volume changes, hindering their practical implementation. Herein, a carbon-coated Cu1.81S/ZnS composite (Cu1.81S/ZnS@C) is rationally designed and synthesized via a high-temperature mixing method (HTMM) in the hydrothermal process and the carbonization process. This unique structure integrates ZnS nanoparticles with Cu1.81S nanosheets, uniformly encapsulated within a conductive carbon matrix. When evaluated as an anode material, the Cu1.81S/ZnS@C composite exhibits significantly enhanced lithium storage performance compared to its single-component counterparts. It delivers a high reversible capacity of 571.4 mAh g-1 at 1 A g-1 after 550 cycles. Kinetic analysis reveals a predominant pseudocapacitive contribution, accounting for its fast reaction kinetics. The outstanding electrochemical performance stems from the synergistic coupling of the Cu1.81S, ZnS, and carbon components. This multi-component integration collectively provides abundant active sites and establishes highly efficient pathways for both ionic diffusion and electronic conduction. Overall, this study highlights the effectiveness of a rationally designed heterostructure with multi-interface synergy in advancing high-performance metal sulfide anodes for next-generation energy storage systems.