Search Results (12,646)

Identifying reliable geochemical signals that reflect crustal stress evolution remains a major challenge in earthquake monitoring. Spring fluids, due to their deep circulation and rapid response, provide an important window into fault-zone processes. This study presents three years (May 2022–March 2025) of hourly hydrogen gas (H₂) concentration monitoring in spring gases from the Muji Basin on the northern Pamir Plateau, integrated with meteorological and seismic data. H₂ concentrations exhibited a stable diurnal pattern, positively correlated with water and air temperatures and negatively correlated with atmospheric pressure. Short-term anomalies during seismically quiet periods may reflect a combination of temperature-dependent solubility effects and transient degassing caused by localized gas accumulation and sudden release under heterogeneous fault and aquifer conditions. During seismically active phases, sustained increases in H₂ concentrations were also recorded; however, such anomalies did not consistently precede earthquakes, instead reflecting broader phases of tectonic instability and episodic fault-zone degassing. These findings highlight the potential of long-term H₂ monitoring to improve our understanding of the coupling between crustal stress, fluid transport, and degassing processes in tectonically active regions. Full article

Sand pear is a fruit tree crop with high economic value, widely cultivated in East Asia. However, ripening fruits often suffer from high-temperature stress, which has adverse effects on the quality and yield of the fruit. In this study, we perform high-temperature treatment on mature stage ‘Housui’ pear fruits. The results showed that heat stress decreased fruit firmness and mineral elements, as well as lead to the flesh appearance of watercore. High temperature induces H₂O₂, MDA, and the antioxidant enzyme activity including SOD, APX, POD, and CAT were significantly increased. Transcriptome and metabolomic analyses revealed that heat stress up-regulated genes related to sucrose synthesis (SPS) while down-regulating those involved in sucrose degradation (SS and NI), resulting in sucrose accumulation. Moreover, the expression of sorbitol dehydrogenase (SDH) and sorbitol transporter (SOT) genes was markedly suppressed, leading to sorbitol accumulation and impaired transport, which promoted watercore development. High temperature also stimulated the expression of ethylene synthesis genes, accelerating abnormal ripening of fruits. In addition, high temperature decreased the accumulation of organic acid and bioactive compounds. Additionally, several antioxidant enzymes genes, five heat shock transcription factors (HSFs) and 34 heat shock protein (HSP) genes were significantly up-regulated. Together, these findings provided new insights into the transcriptional response and metabolomic reprogramming of sand pear response to high-temperature stress. Full article

Space weather exerts a significant influence on the Earth’s atmosphere, driving a variety of physical processes, including the production of cosmogenic radionuclides. Among these, ⁷Be is a naturally occurring radionuclide formed through spallation reactions induced by cosmic-ray showers interacting with atmospheric constituents, primarily oxygen and nitrogen. Over long timescales, the atmospheric concentration of ⁷Be exhibits a direct correlation with the cosmic-ray flux reaching the Earth and an inverse correlation with solar activity, which modulates this flux via variations of the heliosphere. The large availability of ⁷Be concentration data, resulting from its use as a natural tracer employed in atmospheric transport studies and in monitoring the fallout from radiological incidents such as the Chernobyl disaster, can also be exploited to investigate the impact of space weather conditions on the terrestrial atmosphere and related geophysical processes. The present study analyzes a long-term dataset of monthly ⁷Be activity concentrations in air samples collected at ground level since 1987 at the ENEA Casaccia Research Center in Rome, Italy. In particular, the linear correlation of this time series with the galactic cosmic ray flux on Earth and solar activity have been investigated. Data from a ground-based neutron monitor and sunspot numbers have been used as proxies for galactic cosmic rays and solar activity, respectively. A centered running-mean low-pass filter was applied to the monthly ⁷Be time series to extract its low-frequency component associated with cosmic drivers, which is partially hidden by high-frequency modulations induced by atmospheric dynamics. For Solar Cycles 22, 23, 24, and partially 25, the analysis shows that a substantial portion of the relationship between stratospheric ⁷Be concentrations and cosmic drivers is captured by linear correlation. Within a statistically consistent framework, the evidence supports a correlation between ⁷Be and cosmic drivers consistent with solar-cycle variability. The ⁷Be radionuclide can therefore be regarded as a reliable atmospheric tracer of cosmic-ray variability and, indirectly, of solar modulation. Full article

The tall wheatgrass Thinopyrum ponticum has excellent saline–alkali tolerance and great potential for restoring saline–alkali land to enhance productivity. This study used the Thinopyrum ponticum cv. “Orbit” variety, which is widely planted in saline–alkali pastures, as the material and artificially simulated salt stress using 150 mM NaCl and 150 mM Na₂SO₄, respectively. The growth and physiological indexes of the leaves and roots of seedlings were measured after various treatment durations, and the transcriptomes of untreated and Na₂SO₄-treated leaves and roots were also analyzed after 24 h of treatment. The results showed that salt stress resulted in significant reductions in leaf relative water content in seedlings and inhibited root elongation growth, with Na₂SO₄ treatment producing a greater impact on plant growth than NaCl treatment. Salt stress significantly alters ion transport and distribution in Thinopyrum ponticum, characterized by pronounced Na⁺ accumulation and a concomitant decline in K⁺ uptake. Additionally, to adapt to salt stress, roots enhance their ability to absorb and transport essential cations, such as Ca²⁺, Mg²⁺, Fe³⁺, and Cu²⁺. RNA-Seq analysis identified 1682 and 2816 differentially expressed genes (DEGs) in leaves and roots under Na₂SO₄ stress, respectively, with 210 common DEGs. Enrichment analyses revealed that DEGs were primarily associated with redox homeostasis, ion balance, and signal transduction. Furthermore, transcription regulation analysis indicated the Thinopyrum ponticum can coordinate the activation of NAC/MYB/WRKY transcription factors, SA/ETH hormone signaling, and Ca²⁺ pathways in response to salt stress. In summary, this study systematically reveals for the first time the molecular mechanisms by which Thinopyrum ponticum responds to Na₂SO₄ stress through coordinated regulation of ion transport, transcription factor networks, and hormone-Ca²⁺ signaling pathways. Based on transcriptomic and protein–protein interaction analyses, nine key candidate genes for saline–alkali tolerance were identified, including UGT7472, JMT, T4E14.7, CAX5, CP1, PXG2 NAMT1, BON3, and APX7. These findings provide novel genetic resources and a theoretical foundation for breeding salt–alkali-tolerant crops. Full article

The mycoheterotrophic orchid Gastrodia elata relies entirely on symbiosis with Armillaria for nutrient acquisition during tuber development. The signaling mechanisms underlying this interaction have long been a research focus, and several pathways, such as phytohormone-mediated signaling, have been reported. However, the role of plant-derived extracellular vesicles (PDEVs) in G. elata–Armillaria communication remains unexplored. In this study, we conducted a comprehensive lipidomic analysis of G. elata-derived extracellular vesicles (GDEVs) isolated from juvenile, immature (active symbiosis), and mature tubers. By employing high-resolution mass spectrometry and advanced statistical methods, we established a detailed EV lipidome profile for G. elata, identifying 996 lipid species spanning eight major classes. Distinct lipidomic remodeling was observed throughout tuber maturation. Notably, as the immature stage corresponds to the period of peak symbiotic activity, targeted lipidome comparisons enabled the identification of core lipid markers, particularly Glc-sitosterols and the polyketide 7,8-dehydroastaxanthin, which are highly enriched during active symbiosis and potentially associated with inter-kingdom communication. These findings suggest that developmentally regulated lipid transport via EVs plays a critical role in mediating G. elata–Armillaria interaction. Our work not only illuminates the contribution of vesicle lipids to plant–fungal interaction but also provides a methodological foundation for investigating EV-mediated signaling in non-model plant–microbe systems. Full article

Scaffold architecture is a key determinant of cell behavior and tissue regeneration in bone tissue engineering, yet the influence of pore size under dynamic culture conditions remains incompletely understood. This study aimed to evaluate the effects of scaffold pore size on osteogenic differentiation of porcine bone marrow-derived mesenchymal stem cells (pBMSCs) cultured in a rotational oxygen-permeable bioreactor system (ROBS). Three-dimensionally (3D) printed beta-tricalcium phosphate (β-TCP) scaffolds with pore sizes of 500 µm and 1000 µm were seeded with pBMSC and cultured for 7 and 14 days under dynamic perfusion conditions. Gene expression analysis revealed significantly higher levels of osteogenic markers (Runx2, BMP-2, ALP, Osx, Col1A1) in the 1000 µm group, particularly at the early time point, with the later-stage marker Osteocalcin (Ocl) rising faster and higher in the 1000 µm group, after a lower expression at 7 days. ALP activity assays corroborated these findings. Despite having lower mechanical strength, the 1000 µm scaffolds supported a homogeneous cell distribution and high viability across all regions. These results suggest that larger pore sizes enhance early osteogenic commitment by improving nutrient transport and fluid flow in dynamic culture. These findings also support the use of larger-pore scaffolds in bioreactor-based preconditioning strategies and underscore the clinical importance of promoting early osteogenic differentiation to reduce in vitro culture time, an essential consideration for the timely preparation of implantable grafts in bone tissue engineering. Full article

Infections caused by carbapenem-resistant Enterobacterales (CRE), particularly those harboring metallo-β-lactamases (MBLs) such as VIM, constitute a significant public health threat due to the paucity of effective therapeutic options. Cefiderocol (CFD), a novel siderophore-conjugated cephalosporin, exhibits potent activity against CRE by exploiting bacterial iron uptake systems. Nevertheless, the emergence of CFD resistance has been recently documented. This study aimed to characterize the development of CFD resistance in a VIM-producing Klebsiella pneumoniae isolate during antimicrobial treatment. Antimicrobial susceptibility was assessed by broth microdilution using iron-depleted medium according to EUCAST guidelines. Whole-genome sequencing and comparative genomic analyses focused on mutations in genes related to iron transport and CFD resistance, using Illumina MiSeq. Initial isolates (RS, BA1) were susceptible to CFD (MIC 2 mg/L), whereas the isolate recovered after 9 days of CFD therapy (BA2) was resistant (MIC 8 mg/L). In conclusion, this study illustrates for the first time the rapid emergence of CFD resistance in a VIM-producing ST307 K. pneumoniae isolate linked to a missense variant in envZ gene, arising after a 9-day CFD treatment. Full article

Percocypris pingi was listed in the China Vertebrate Red List in 2015, and albino P. pingi exhibits remarkable ocular phenotypes due to melanin synthesis defects, including the deficiency of melanin granules in the iris and retinal pigment epithelium (RPE). However, the regulatory mechanism of pigment loss in the eyes of albino P. pingi has not yet been clarified. This study systematically revealed the potential mechanisms underlying the obstruction of ocular melanin synthesis in albino P. pingi through histopathological analysis, transcriptomics, and proteomics techniques. The results showed that the synergistic effects of abnormal H⁺ transport mediated by SLC45A2, excessive activation of retinol metabolism, and cytoskeletal transport disorders led to the inhibition of tyrosinase activity and retention of pigment granules, ultimately causing melanin deficiency in the eyes. This study first elucidates the molecular network of ocular albinism in fish from a multi-omics perspective, providing a new perspective for the mechanistic research of pigmentation disorders in vertebrates. Full article

Cascading link failures continue to imperil power grids, transport networks, and cyber-physical systems, yet the relationship between a network’s robustness at the moment of attack and its subsequent resiliency remains poorly understood. We introduce a dynamic framework in which connectivity-based cascades and distributed self-healing act concurrently within each time-step. Failure is triggered when a node’s active-neighbor ratio falls below a threshold $\phi$; healing activates once the global fraction of inactive nodes exceeds trigger $T$ and is limited by budget $B$. Two real data sets—a 332-node U.S. airport graph and a 1133-node university e-mail graph—serve as testbeds. For each graph we sweep the parameter quartet ($\phi ,\hspace{0.17em}B,\hspace{0.17em}T,attackmode$) and record (i) immediate robustness $R$, (ii) 90% recovery time T₉₀, and (iii) cumulative average damage. Results show that targeted hub removal is up to three times more damaging than random failure, but that prompt healing with $B\ge 0.12$ can halve T₉₀. Scatter-plot analysis reveals a non-monotonic correlation: high-$R$ states recover quickly only when $B$ and $T$ are favorable, whereas low-$R$ states can rebound rapidly under ample budgets. A multiplicative fit $T_{90}\propto B^{-\beta }g\left(T\right)h\left(R\right)$ (with $\beta \approx 1$) captures these interactions. The findings demonstrate that structural hardening alone cannot guarantee fast recovery; resource-aware, early-triggered self-healing is the decisive factor. The proposed model and data-driven insights provide a quantitative basis for designing infrastructure that is both robust to failure and resilient in restoration. Full article

Element doping and functional group modification engineering serve as efficient approaches that contribute to the improvement of the functional efficiency in graphitic carbon nitride (CN) materials. A CN photocatalyst co-modified with sulfur (S) and cyano moieties was prepared through thermal condensation polymerization. The introduced S species modulated the band structure, increased charge carrier mobility, and significantly promoted charge separation and transport. Additionally, the introduction of cyano groups extended light absorption range and improved the material’s selective adsorption of reactant molecules. The as-prepared sulfur-modified CN photocatalyst obtained after a 6 h thermal treatment, which was capable of degrading organic pollutants and producing hydrogen (H₂) efficiently and stably, exhibited excellent catalytic performance. The photocatalyst’s photocatalyst exhibited a significantly enhanced photocatalytic activity, with a Rhodamine B (RhB) removal efficiency reaching 97.3%. Meanwhile, the H₂ production level reached 1221.47 μmol h⁻¹g⁻¹. Based on four-cycle experiments, the photocatalyst exhibited excellent recyclability and stability in both H₂ production processes and photocatalytic organic pollutant degradation. In addition, mechanistic studies confirmed the dominant role of ·OH and ·O₂⁻ as active species responsible for the reaction system’s performance. This study highlights that the co-decoration of heteroatoms and functional groups can markedly enhance the photocatalytic performance of CN-based materials, offering considerable potential for future applications in energy conversion and environmental remediation. Full article

This study evaluated the effectiveness of essential oil from Aloysia citrodora (EOAC) (48% citral and 19% limonene) for use in anesthesia and simulated transport of tambaqui (Colossoma macropomum) juveniles at two cargo densities (CDs). Concentrations of 0 (control), 10, 25, 50, 100, 150, 200, and 250 µL EOAC L⁻¹ were tested for use in anesthesia induction and recovery, while 0 (control) and 20 µL EOAC L⁻¹ were tested for their effects on the ventilatory rate (VR) and during 6 h simulated transport at a low CD (LCD, 65 g L⁻¹) and standard CD (SCD, 130 g L⁻¹). Fish were anesthetized at EOAC concentrations above 50 µL L⁻¹, with the optimal anesthesia (141.83 s) and recovery times (160.00 s) at 250 µL L⁻¹. The water unionized ammonia was lowest in the EOAC-LCD group. Using 20 µL EOAC L⁻¹ during transport minimized changes in the hematological parameters (erythrocytes, hemoglobin, hematocrit, total leukocytes, and heterophils) and reduced the liver aspartate aminotransferase activity at both CDs. Transport at an SCD, regardless of EOAC use, increased the plasma glucose, hepatic glycogen, and alanine transaminase activity. The VR was higher with 20 µL EOAC L⁻¹ than in the control group. In conclusion, our findings confirm that 20 µL EOAC L⁻¹ can effectively be used to transport tambaqui for up to 6 h without impairing fish health. Full article

In the context of increasing environmental and social challenges, sustainable tourism—and particularly awareness of climate-related threats—plays a crucial role in protecting the environment. Certain travel behaviors, such as inappropriate choices of transportation or vacation destinations, have a significant impact on it. Generation Z, defined as individuals born after 1995, stands out due to the cohort’s high environmental awareness and openness to new technologies, which may influence their tourism choices. The aim of this study is to verify hypotheses concerning the main reasons for travel reduction among Generation Z and to identify the relationships between selected demographic factors, such as place of residence and source of income, and the tourism activity of this social group. Statistical methods were employed, and a chi-square test was used to analyze the relationship between the decision to forgo travel and variables such as place of residence and source of income. The results indicate that place of residence and income source are not significantly associated with the likelihood of engaging in tourism in 2024. A considerable proportion of young respondents reported refraining from travel primarily due to a lack of free time. Financial and environmental concerns also played important roles. Tourism policy should therefore consider not only economic and spatial factors but also the growing ecological awareness, promoting sustainable forms of tourism and initiatives that enhance accessibility for diverse social groups. Full article

Excessive nitrogen export from lowland polders is a key contributor to cultural eutrophication in downstream aquatic ecosystems. This study investigated the spatiotemporal characteristics, migration pathways, and sources of nitrogen pollution in a typical polder system. Eight surface water sampling campaigns were conducted at 13 sites in Quyuan Polder, Dongting Lake, from 2022 to 2023, combining ArcGIS spatial analysis, multivariate statistics, and dual-isotope (δ¹⁵N-NO⁻), δ¹⁸O-NO₃⁻) techniques. Nitrate and ammonium nitrogen dominated the nitrogen pool, accounting for ~76% of total nitrogen. Concentrations were higher in the dry season (2.48 mg/L) than in the wet season (1.89 mg/L) and differed significantly among hydrological periods (p < 0.05). Within the polder, total nitrogen and ammonium nitrogen were elevated, whereas nitrate nitrogen was higher at the outlet, reflecting distinct nitrogen profiles along the hydrological gradient. Nitrogen transport patterns were largely consistent with flow direction, driven by both upstream inputs and in situ generation. Isotopic signatures indicated that nitrate originated mainly from ammonium fertilizer and soil nitrogen, with contributions from manure and sewage. These findings enhance understanding of nitrogen dynamics in lowland catchments and provide a scientific basis for targeted pollution control in polder waters. Full article

With the rapid development of the Internet of Things (IoT) applications, the ability to automatically discover and retrieve resource information has become increasingly enhanced. Despite being one of the most commonly used IoT communication protocols, Message Queuing Telemetry Transport (MQTT) does not natively support resource discovery. To address this limitation, MQTT-resource discovery (MQTT-RD), a resource discovery mechanism based on MQTT, has been used for resource management. In this study, we tested and evaluated MQTT-RD using the Sniffer system that manages the resource directory and synchronizes data via MQTT. When too many Sniffers are activated, the MQTT-RD system becomes unsustainable. However, the experimental results in this study revealed that frequent updates to the resource directory (RD) and high-frequency heartbeat messages (pingalive) significantly increase network traffic and system load. In this study, we identified performance and stability issues to propose improvement strategies, including refining the topic design, reducing message transmission frequency, and improving the synchronization mechanism. Additionally, the feasibility of incorporating centralized management was explored to enhance system efficiency. Full article

Active school transportation (AST), including walking or cycling to school, is common among children and youth in India. However, rising air pollution and public health advisories may encourage parents to restrict outdoor activities. The role of parental restrictions on children’s and youths’ participation in AST remains largely unexplored. This study examines how parental restrictions on outdoor activity influence children’s and youths’ engagement in AST. We surveyed children and youth aged 5 to 17 from 41 schools across 28 urban and rural locations in five Indian states, collecting data on AST, parental restrictions, perceptions of air pollution, sociodemographic factors, and school distance. Data were analyzed using multiple logistic regression models, adjusted and unadjusted for children’s and youths’ perceptions of air pollution, segregated by age, gender, and location. Reported parental restrictions due to air pollution were associated with lower odds of engaging in AST overall (OR = 0.625, 95% CI = 0.400–0.971), for ages 5–12 (OR = 0.460, 95% CI = 0.208–0.985, and in urban areas (OR = 0.433, 95% CI = 0.198–0.881). Adjusting for children’s and youths’ air pollution perceptions, these associations persisted in overall and urban analyses. Living over 2 kilometres from school also lowered odds of AST participation (p < 0.05 across all models). The interplay between AST, air pollution, and parental restrictions is self-reinforcing: air pollution can trigger parents to restrict child and youth mobility and reduce AST and, in turn, lower AST may contribute to worsening air quality because of increased motorized transport. Integrated policies are required to simultaneously mitigate pollution and enhance active transportation infrastructure. Full article