Search Results (2,649)

Earth’s early history provides the only natural record for evaluating how planetary evolution can generate environments capable of initiating life. Here we review early Earth evolution through the lens of urability: the time-dependent capacity of planetary environments to support prebiotic chemistry progressing toward compartmentalized, self-propagating, information-bearing systems. We argue that urability is not a single globally habitable state, but a transient overlap among several coupled dimensions: liquid water availability, permissive temperature, ocean pH and salinity, access to bioessential elements, atmospheric shielding and volatile retention, and exposed or shallow environments that enable concentration, mineral catalysis, and wet–dry cycling. During the Hadean–early Archean transition, these dimensions were shaped by magma-ocean degassing, late accretion history, atmospheric compositional evolution from CO₂-rich to more N₂-dominated states, ferruginous ocean chemistry, tectonic recycling, continental growth, and intermittent land emergence. These processes created tradeoffs: high pCO₂ may have enhanced abiotic nitrogen fixation but imposed hot and acidic conditions, whereas CO₂ drawdown improved climate and ocean pH while weakening some fixed-nitrogen sources; ferruginous chemistry could locally enhance phosphate availability while also promoting nutrient scavenging; and tectonic recycling could stabilize the carbon cycle while generating chemically diverse but spatially intermittent land environments. We therefore frame life’s origin as a planetary timing problem, in which prebiotic opportunities opened and closed as multiple environmental constraints came into and out of overlap. This perspective motivates coupled models that resolve when and where water, temperature, pH, nutrients, energy, atmospheric photochemistry, and exposed land surfaces jointly produced urable environments on Earth and other rocky planets. Full article

The durability deterioration of concrete under the coupled action of freeze–thaw cycles and corrosive media is a critical technical challenge for engineering structures in cold regions and salt corrosive environments. This paper systematically reviews the research progress on the mechanical properties of concrete subjected to coupled freeze–thaw and corrosion effects. Starting from the mechanisms of freeze–thaw damage and corrosion damage, it analyzes the material degradation laws under individual factors and the synergistic failure mechanism of the coupled freeze–thaw–corrosion condition. The coupling effect is revealed: freeze–thaw-induced microcracks accelerate the penetration of corrosive media, while the expansion of corrosion products in turn aggravates freeze–thaw damage. Building on this, from the perspective of factors influencing concrete failure, this paper systematically summarizes the key factors governing concrete damage under single-factor and coupled-factor conditions as well as their nonlinear response characteristics. The review indicates that the damage degree under the coupled action is far greater than the simple superposition of damage caused by individual factors and presents complex patterns, including the concentration threshold effect, the time-sequence effect, and sensitivity to a low water–cement ratio. Existing reviews predominantly focus on qualitative descriptions of single-factor deterioration mechanisms, while systematic comparative analyses of threshold behaviors under multi-factor coupling and quantitative consolidation of mechanical degradation metrics remain limited. Furthermore, targeted durability design guidance tailored to cold saline environments is rarely summarized in the prior literature, which motivates the present comprehensive review. Although existing studies are relatively well-established for single damage mechanisms, further efforts are still needed to deepen the understanding of multi-factor interaction thresholds and dynamic evolution processes. The findings of this review can provide theoretical support and engineering reference for the durability design and service life prediction of concrete structures in cold regions and salt corrosive environments. The summarized threshold laws and quantitative mechanical degradation data can provide targeted parameter guidance for the durability design of hydraulic structures, bridge substructures, and port engineering in northwest saline soil, northern severe cold, and eastern coastal salt fog areas. Full article

Medicinal and aromatic plants are important sources of secondary metabolites used in pharmaceutical, cosmetic, nutraceutical, and health-related applications. However, the phytochemical and bioactive composition of plant raw materials is often highly variable because it is influenced by genotype, developmental stage, cultivation environment, and post-harvest conditions. Controlled environment agriculture (CEA) offers an opportunity to reduce this variability by regulating key aboveground and root-zone factors under reproducible cultivation conditions. This review synthesizes recent research on how environmental control in CEA can influence plant metabolism, biomass formation, phytochemical accumulation, and production value in medicinal and aromatic plants. Particular attention is given to light spectrum and quantity, UV radiation, air temperature, vapor pressure deficit, CO₂ concentration, nutrient solution composition, pH, electrical conductivity, root-zone temperature, salinity, and chemical elicitors. The review distinguishes general environmental regulation from controlled elicitation: some factors primarily support growth, resource-use efficiency, and product consistency, whereas others can be applied as defined stimuli to activate stress-related or defense-related secondary metabolism. Evidence indicates that these factors can modify phenolics, flavonoids, terpenoids, alkaloids, essential-oil constituents, and other bioactive compounds. However, reported phytochemical changes should not be evaluated only by metabolite concentration but also by biomass production, resource input, technological feasibility, and batch-to-batch consistency. The review also highlights the need to move from single-factor optimization toward integrated, plant-informed control strategies that account for factor interactions, treatment timing, genotype specificity, non-destructive feedback, and realistic energy and resource constraints. Integrating plant physiology, phytochemistry, environmental control, and production technology may support the development of CEA as a framework for developing phytochemical standardization protocols and more reproducible production of high-value medicinal plant material, although further validation across batches, production cycles, and resource inputs is required. Full article

Saline irrigation is a major constraint on vegetation establishment in arid coal-mining landscapes. Nitraria tangutorum Bobrov is a xerohalophytic shrub established in the Dananhu mine-restoration area of Hami, Xinjiang, but its physiological responses to long-term saline irrigation remain insufficiently characterized. In this field study, approximately two-year-old plants were maintained for approximately two growing seasons under freshwater drip irrigation or irrigation water containing 8 or 12 g L⁻¹ total dissolved solids. Unlike short-term controlled salinity assays that evaluate individual response pathways, the present field study integrates root and shoot responses across osmolyte accumulation, oxidative injury, redox regulation, nitrogen metabolism, phytohormone signaling, and lipid remodeling under long-term mixed-salt irrigation. Increasing salinity significantly reduced shoot total chlorophyll content, whereas shoot carotenoid content showed a nonsignificant numerical increase. Soluble sugars, proline, and soluble proteins increased, while total free amino acids declined. Superoxide anion (O₂⁻), hydrogen peroxide (H₂O₂), and malondialdehyde (MDA) increased progressively, demonstrating oxidative injury. The protein concentrations of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX) increased, whereas glutathione peroxidase (GSH-PX) and glutathione reductase (GR) declined. Concurrent decreases in ascorbic acid/ascorbate (AsA) and reduced glutathione (GSH), together with increases in dehydroascorbic acid (DHA) and oxidized glutathione (GSSG), indicated progressive oxidation of the cellular redox environment. Nitrate reductase (NR) declined under salinity, while glutamine synthetase (GS) and glutamate synthase (GOGAT) increased at 8 g L⁻¹ but decreased at 12 g L⁻¹. Growth-associated hormones declined, whereas stress-associated hormones increased. Together, these responses reveal a dose-dependent transition from co-occurring biochemical adjustment and oxidative injury at 8 g L⁻¹ to broader redox and metabolic disruption at 12 g L⁻¹ under long-term field irrigation. These variables provide candidate indicators of downstream salinity response, but ion homeostasis, plant water status, growth, survival, and long-term performance must be evaluated before salt tolerance or irrigation thresholds can be established. Full article

Understanding the relationships among plant functional traits and how these are shaped by the soil environment is essential for the study of plant adaptation. Conducted in the desert ecosystem surrounding Ebinur Lake, China, this study assessed key functional traits for eight common desert plant species, including the foliar carbon (C), nitrogen (N), and phosphorus (P) content, and their stoichiometric ratios (C:N, C:P, N:P), as well as the chlorophyll content (Chl), leaf area (LA), and leaf thickness (LT). Separate plant trait networks (PTNs) were constructed for herbs, shrubs, and trees growing in two distinct soil environments: those with high (HS) versus low (LS) soil moisture and salinity. The study had three key findings. (1) Both soil properties and plant functional traits differed between HS and LS environments (p < 0.05). (2) Distinct PTNs were observed among plant life forms, with different central traits. Herbs (central traits: leaf thickness and the N:P ratio) had high-density PTNs demonstrating strong adaptability, while shrubs (central traits: C and P) and PTNs had high connectivity that was stable across soil environments; tree PTNs (central traits: N and the C:P ratio) were highly modular and showed strong resistance to disturbance. (3) Soil factors also regulated PTN topology, with the total nitrogen (TN) and total phosphorus (TP) being key regulators in HS, while the soil salt content and water content were the most important factors in LS. In conclusion, the PTNs of desert plants reflected their unique adaptations to arid environments, and the application of these findings should support efforts to conserve and manage desert vegetation. Full article

Estuaries support distinct spawning and nursery habitats for migratory fishes, yet the differential environmental response patterns between these two critical early life habitats remain poorly understood from a spatial non-stationarity perspective. Based on six ichthyoplankton surveys conducted during peak and late spawning seasons from 2018 to 2020 in the Yangtze Estuary, this study applied geographically weighted regression (GWR) models to quantify the spatially varying effects of sea surface temperature, sea surface salinity, chlorophyll-a, water depth and distance to coast on the distributions of Coilia mystus eggs and larvae. The results reveal clear divergence in both spatial pattern and environmental drivers between spawning and nursery habitats. Spawning grounds were persistently concentrated in the middle reaches of the South Branch, and shifted approximately 10 km upstream during the spring saltwater intrusion event in 2020. Nursery grounds, by contrast, formed a stable dual-core structure, with the northern core at the North Branch mouth consistently supporting higher larval densities than the southern core in the North and South Passages. Salinity was the primary limiting factor for spawning in spring, while temperature dominated in summer, and chlorophyll-a was never retained in optimal egg models. For larvae, chlorophyll-a emerged as a consistent key driver alongside salinity and temperature, and local regression coefficients spanned a wider range than those for eggs, indicating greater spatial heterogeneity in larval distribution–environment relationships. This study provides the first comparative analysis of spatially non-stationary environmental controls on spawning versus nursery habitats of C. mystus, and offers empirical support for stage-specific habitat conservation and fisheries management in the Yangtze Estuary. Full article

Compared with traditional Al–Si die-cast alloys, which have good formability and low cost but poor brazeability and inadequate corrosion resistance, high-pressure die-cast (HPDC) Al–RE alloys exhibit superior comprehensive properties. To satisfy the demand for lightweight, high-performance materials in automotive thermal management, a controlled-atmosphere brazing (CAB) furnace was employed in this work to investigate the effect of the complete brazing cycle on the microstructure, mechanical properties, and corrosion resistance of the HPDC Al–RE alloy. In the as-cast state, the eutectic Al₁₁(La,Ce)₃ phase presents a lamellar structure. After the simulated brazing process, this phase transforms into dispersed near-spherical particles. Such microstructural evolution directly determines the mechanical and corrosion behaviors of the alloy. The yield strength and ultimate tensile strength decrease, while the elongation increases substantially owing to the alleviation of stress concentration. The corrosion resistance of the alloy depends on the service environment. After 960 h of neutral salt spray (NSS) testing, the alloy showed excellent corrosion resistance with only slight corrosion. Nevertheless, severe localized pitting corrosion (maximum pit depth: 0.932 mm) was observed after 480 h of sea water acidified accelerated test (SWAAT) exposure. This pitting phenomenon is directly associated with spheroidized Al₁₁(La,Ce)₃ particles. In acidic chloride-containing media, these intermetallic particles undergo preferential anodic dissolution relative to the α-Al matrix, resulting in micro-galvanic corrosion. In conclusion, after simulated brazing treatment, the ductility of the Al–RE alloy is remarkably improved at the cost of a moderate reduction in strength. The Al–RE alloy possesses good corrosion resistance in neutral saline environments. However, severe localized corrosion tends to occur in acidic environments due to the high electrochemical activity of spheroidized intermetallic phases. Full article

Continuous paddy reclamation is a promising strategy for restoring sodic lands, yet the exact mechanisms driving soil organic carbon (SOC) stabilization remain insufficiently quantified. Here, we investigated SOC dynamics across a 12-year rice cultivation chronosequence (0, 2, 5, 10, and 12 years) at 0–20 cm and 20–40 cm depths in western Jilin Province, China. Successive rice cultivation progressively alleviated saline–alkaline stress, with electrical conductivity (EC) decreasing by 70.11% in topsoil after 12 years, establishing a stabilized soil environment by years 10–12. Concurrently, topsoil SOC and total nitrogen (TN) increased by 63.09% and 26.02%, respectively. This physicochemical amelioration triggered a directional carbon transformation: while particulate organic carbon (POC) accumulated in early stages, mineral-associated organic carbon (MAOC) dominated medium-term storage, expanding by 147.12% in topsoil and elevating its share of SOC. Fourier transform infrared (FTIR) spectroscopy confirmed a shift toward molecular structural persistence, marked by increased aromaticity and hydrophobicity. Partial least squares path modeling (PLS-PM) demonstrated that cultivation duration directly drove soil stability (β = 0.94, p < 0.001), operating through a hierarchical cascade where management-induced stress reduction enhanced soil enzyme activity and microbial processing, thereby accelerating the conversion of labile plant inputs into mineral-protected MAOC. Overall, this study quantifies the pivotal role of paddy management in driving organo-mineral protection and chemical persistence, providing a mechanistic framework for carbon sequestration in degraded agroecosystems. Full article

The selection and breeding of salt-tolerant rice and the use of saline–alkali land for rice cultivation are crucial for food security. However, most studies have focused only on the seedling salt tolerance stage, with little research on the salt tolerance mechanisms during the reproductive growth period. This study selected the salt-tolerant rice line SR17, the salt-tolerant variety SR86, and the salt-sensitive variety IR29 as research subjects. Two salt stress gradients of 0% and 0.5% (7.8 dS m⁻¹) were established. Salt stress was applied continuously from rice transplanting to the maturity stage, and the differences in response mechanisms during the young panicle stage under long-term salt stress were analyzed. The results showed that, under salt stress, SR17 exhibited the least lipid peroxidation and membrane damage, followed by SR86, while IR29 suffered the most severe damage. SR17 and SR86 could reduce oxidative damage and maintain membrane system integrity by activating the antioxidant enzyme system and accumulating soluble proteins. In contrast, the antioxidant system in IR29 was insufficiently activated; this indicates that the adaptability of this variety to salt-induced oxidative stress is relatively poor. The chlorophyll content and most photosynthetic parameters in SR17 showed no significant changes, and leaf gas exchange performance and chlorophyll status were the least affected, whereas IR29 suffered severe damage. Agronomic trait investigation revealed that, compared with the control, SR17 exhibited the smallest reductions in plant height, spikelets per panicle, 1000-grain weight, grain yield per plant, and main spikelet number under salt stress, and the decreases in key yield-related indicators—effective panicle number, grain yield per plant, and seed setting rate—were not significant. This study confirms that SR17 possesses superior salt tolerance and holds potential for further breeding and multi-environment trials, while also providing an important basis for elucidating the physiological mechanisms of salt tolerance during the reproductive stage of rice. Full article

If a CO₂ reservoir or transmission pipeline were to leak, both the surrounding ecology and maritime traffic safety could be put at risk. To better understand and prepare for this risk, multiphase Computational Fluid Dynamics (CFD) models were built in ANSYS Fluent to capture the behavior of a leak once it enters the water. A 3D Eulerian–Eulerian model was used for validation, while a simplified 2D model was applied to simulate conditions at a 50-m depth. The models integrate bubble dynamics, gas holdup, CO₂ dissolution, dissolved species transport, and seawater acidification into a unified CFD framework. Mass transfer was calculated using the Hughmark correlation, and local seawater temperature and salinity were factored in to determine dissociation behavior and the relevant Henry’s Law constant. To confirm the 3D model’s accuracy, results were checked against two experimental datasets: the QICS field study and the Hauser Tank experiments. The team also modeled a hypothetical release scenario at the High Island 10L site and compared the results with earlier published work. The results show that at a depth of 50 m, the surrounding water column can completely absorb a CO₂ release at a rate of 35 kg/s, since the gas dissolves into the seawater as it rises toward the surface. Beyond confirming this mitigation capacity, the simulations shed light on how a leak would actually unfold in the environment, including the shape and movement of the rising bubble plume, how much CO₂ dissolves along the way, and the resulting shifts in seawater pH and pCO₂. Together, this provides a practical framework for assessing how CO₂ leaks could affect marine environments in the Gulf of Mexico. Full article

Synovitis is an inflammatory disorder in horses that contributes to cartilage degradation and osteoarthritis. This study evaluated the effects of intra-articular administration of high-molecular-weight (HMW), linear (non-cross-linked) hyaluronic acid (HA) in an equine model of lipopolysaccharide (LPS)-induced acute synovitis. In this randomized blinded study, acute synovitis was induced in radiocarpal joints of 16 adult horses using LPS (0.25 ng). After 12 h, joints were treated intra-articularly with either 2 mL of phosphate-buffered saline (PBS; control group) or 2 mL of HMW-HA (20 mg/mL; 2280 kDa; treatment group). Horses underwent orthopedic, ultrasonographic, and synovial fluid evaluations. Horses treated with HMW-HA exhibited lower synovial membrane thickening and reduced lameness scores compared with controls. Synovial fluid analysis demonstrated increased concentrations of HMW-HA during the acute inflammatory phase in treated joints. Reduced chondroitin sulfate release was also detected following HMW-HA administration. Lower lipid peroxidation levels (TBARS) were observed in the treated group at 24 h and 14 days. Intra-articular administration of high-molecular-weight linear hyaluronic acid was associated with increased synovial availability of HMW-HA during the acute inflammatory phase, attenuation of pain-related clinical signs and synovial membrane thickening, and modulation of the redox environment. These findings support a modulatory role of linear HMW-HA in the intra-articular environment. Full article

The corrosion behavior of N80 steel in a simulated coalbed–methane environment was investigated in a high-temperature, high-pressure autoclave. Uniform corrosion and maximum pit depth were quantified by weight-loss measurements and ultra-depth-of-field three-dimensional microscopy, respectively, while SEM, EDS, and XRD were used to characterize the morphology, elemental composition, and crystalline phases of the surface corrosion products. A one-factor-at-a-time design was applied at a constant total pressure of 10 MPa to evaluate the effects of nominal CO₂ partial pressure (0.10–1.00 MPa), nominal O₂ partial pressure (0–0.40 MPa), Cl⁻ concentration (3–187 g/L), and temperature (40–75 °C). Increasing the nominal CO₂ partial pressure raised the uniform corrosion rate from 0.712 to 0.930 mm/a but reduced the maximum pitting corrosion rate from 1.691 to 0.280 mm/a, while FeCO₃-containing surface coverage increased. Increasing the nominal O₂ partial pressure intensified both corrosion modes; at 0.40 MPa, the uniform and maximum pitting corrosion rates reached 1.446 and 2.202 mm/a, respectively, and the corrosion-product layer exhibited extensive cracking and spallation. Increasing the Cl⁻ concentration reduced the uniform corrosion rate from 1.078 to 0.839 mm/a but increased the maximum pitting corrosion rate from 0.474 to 1.807 mm/a, indicating a shift in the principal damage risk from average metal loss to localized penetration. The uniform corrosion rate reached a maximum of 1.516 mm/a at 60 °C, whereas the maximum pitting corrosion rate increased continuously to 2.202 mm/a at 75 °C. XRD identified Fe, FeCO₃, Fe₂O₃, Fe₃O₄, and FeOOH. The persistent Fe substrate reflections, interpreted together with the SEM observations, revealed spatially heterogeneous corrosion-product coverage. These results show that the protective contribution of FeCO₃-containing products depends on their surface coverage and visible integrity rather than on phase presence alone. The findings support stringent oxygen-ingress control, targeted pitting protection in high-salinity environments, and enhanced corrosion surveillance of intermediate- and high-temperature well sections. Full article

Photovoltaic technology selection in Gulf Cooperation Council (GCC) desert environments is affected by coupled dust, thermal, ultraviolet (UV), humidity, and salinity stresses, which are not fully represented by static weighting and additive multi-criteria decision-making models. This study develops a GCC evidence-calibrated nonlinear decision-support framework that integrates published literature-derived GCC/desert-stress calibration, adaptive hybrid entropy–desert weighting, and bipolar fuzzy Einstein aggregation. The framework is applied to compare passivated emitter and rear cell (PERC), tunnel oxide passivated contact (TOPCon), and heterojunction technology (HJT) photovoltaic technologies using calibrated evidence from Qatar, the United Arab Emirates, Saudi Arabia, and Oman. The results show that dust tolerance receives the highest final hybrid weight (0.258), followed by thermal resistance (0.228), UV resistance (0.207), efficiency (0.173), and cost effectiveness (0.134). The nonlinear Einstein aggregation ranks HJT first (0.889), followed by TOPCon (0.861) and PERC (0.742). Benchmark comparison with TOPSIS, VIKOR, and PROMETHEE II shows high rank agreement, while Monte Carlo perturbation analysis indicates that HJT preserves the first rank in 93% of perturbation runs. The proposed framework links PV technology selection with published GCC desert-stress evidence and provides a reproducible basis for technology prioritization in harsh solar energy deployment environments. A stress-to-decision translation table is also provided to clarify how desert degradation mechanisms are converted into decision criteria and reusable selection guidance. Full article

Real-time monitoring of radioactive liquid effluents from nuclear power plants (NPPs) is essential for environmental safety assurance, yet existing liquid scintillation counting (LSC) instruments are bulky (>200 kg), laboratory-bound, and incapable of autonomous online deployment. This paper presents the design and implementation of a fully automated online LSC monitoring process integrating seawater sampling, distillation pre-treatment, liquid scintillator mixing, dual photomultiplier tube (PMT) coincidence detection, field-programmable gate array (FPGA)-based digital signal processing, and 4G remote data transmission in a single portable unit weighing 21.59 kg. The automated process executes a complete sample-to-result cycle in approximately 45 min without human intervention. The signal processing chain comprises a dual-PMT coincidence system, a custom two-stage pre-amplifier, a 14-bit 40 MSPS analogue-to-digital converter (ADC; AD9245, Analog Devices, Norwood, MA, USA), and a five-stage FPGA pipeline implementing anti-coincidence rejection, pulse amplitude discrimination, charge comparison method (CCM) waveform discrimination, and convolutional neural network (CNN)-based alpha/beta classification achieving 97.4% accuracy on a Geant4-simulated test set. System performance was validated against a PerkinElmer 1220 QUANTULUS reference spectrometer across a five-point calibration range (0–400 Bq/L; R² = 0.9987, recovery 99.4–101.6%), confirmed via third-party environmental testing (−10 °C to +50 °C, GB/T 2423.1-2008), and verified in field measurements at Tianwan Nuclear Power Plant. The experimentally determined system background is (1.83 ± 0.12) cpm; the calculated minimum detectable activity (MDA) for tritium is 0.073 Bq/mL at 30 min counting time (η = 3.4%, V = 10 mL, T_s = 1800 s per the Currie formulation), satisfying the GB 14587 (the Chinese national standard: Limits of Radioactivity for Liquid Effluents from Nuclear Power Plant) regulatory reference limit of 0.5 Bq/mL with a 7× safety margin. The proposed system is, to the authors’ knowledge, the first reported instrument combining full process automation (including distillation pre-treatment), single-person portability, and real-time 4G remote data transmission for continuous NPP liquid effluent surveillance in high-salinity seawater environments. Full article

The accumulation of polycyclic aromatic hydrocarbons (PAHs) in saline environments poses a threat to ecological security; however, the elimination of PAHs from saline environments is difficult. In this study, a constructed microbial consortium, designated NOMA, was constructed from Novosphingobium sp. J3 and Martelella sp. E4 via a “bottom-up” method. Consortium NOMA degraded phenanthrene within 7 days at 5% salinity and retained phenanthrene-degradation activity across the tested salinity, pH, and Cd²⁺ gradients (pH values of 5–10, salinities of 1–20%, and Cd²⁺ concentrations of 0–50 mg/L). PAH-degrading genes in both strains were annotated based on the genomic information. Based on the genomic information and intermediate detection, a cross-feeding model of the phenanthrene degradation process by consortium NOMA was proposed. Strain J3 was responsible for the upstream degradation of phenanthrene, and strain E4 promoted multiple downstream degradation pathways to increase the rate of intermediate transfer. Genome-scale metabolic model (GSMM) predictions suggested a potential interspecies cross-feeding mechanism: J3 supplies upstream aromatic intermediates, whereas E4 provides complementary nutritional and cofactor-related support to J3. This study deepens the understanding of the cross-feeding pattern of PAHs in saline environments and provides a biological resource for the bioremediation of PAH under saline and cadmium stress conditions. Full article