Search Results (3,272)

Salinity, a critical environmental factor for fish survival, remains poorly understood in terms of how Triplophysa strauchii, a characteristic fish in Northwest China, physiologically responds to salinity stress. This study aimed to determine its salinity tolerance threshold and explore the associated physiological damage mechanisms. Six salinity gradients (11, 11.7, 12.5, 13.3, 14.3, 15.1 ppt) and a freshwater control group were established. Acute toxicity tests recorded mortality and behavior, while physiological–biochemical assays measured ion concentrations and enzyme activities in gills, kidneys, liver, intestines, and plasma over 96 h. The results showed a 96-hour median lethal concentration of 13.31 ppt and a safe concentration of 4.05 ppt. Gills and kidneys, as primary osmoregulatory organs, responded rapidly, whereas the liver and intestine lagged. Salinity ≤ 13.3 ppt allowed the fish to maintain homeostasis via physiological adjustments, but ≥14.3 ppt caused ion imbalance, immune function was significantly suppressed, and irreversible damage. These findings clarify the species’ salinity adaptation strategies, providing a basis for further research on chronic salinity stress. Full article

A learning management system (LMS) plays a crucial role in supporting students’ educational activities by centralized platforms for course delivery, communication, and student support. Recently, many universities have integrated chatbots into their LMS to assist students with various inquiries and tasks. However, existing chatbots often necessitate human interventions to manually respond to complex queries, resulting in limited scalability and efficiency. In this paper, we present a memory-augmented large language model (LLM) framework that enhances the reasoning and contextual continuity of LMS-based chatbots. The proposed framework first embeds user queries and retrieves semantically relevant entries from various LMS resources, including instructional documents and academic frequently asked questions. Retrieved entries are then filtered through a two-stage confidence filtering process that combines similarity thresholds and LLM-based semantic validation. Validated information, along with user queries, is processed by LLM for response generation. To maintain coherence in multi-turn interactions, the chatbot incorporates short-term, long-term, and temporal event memories, which track conversational flow and personalize responses based on user-specific information, such as recent activity history and individual preferences. To evaluate response quality, we employed a multi-layered evaluation strategy combining BERTScore-based quantitative measurement, an LLM-as-a-Judge approach for automated semantic assessment, and a user study under multi-turn scenarios. The evaluation results consistently confirm that the proposed framework improves the consistency, clarity, and usefulness of the responses. These findings highlight the potential of memory-augmented LLMs for scalable and intelligent learning support within university environments. Full article

The safety profile of Lentilactobacillus buchneri KU200793, which has neuroprotective effects, was comprehensively evaluated through both phenotypic and genotypic analyses. Phenotypically, the strain exhibited no β-hemolysis, mucin degradation, indole production, gelatin liquefaction, urease activity, or β-glucuronidase activity. Additionally, it did not produce D-lactate, and only trace amounts of spermidine were detected among the biogenic amines. Furthermore, L. buchneri KU200793 did not exhibit bile salt deconjugation, further supporting its safety profile. However, its tetracycline resistance exceeded the threshold set by the European Food Safety Authority. Genotypic analysis using the HGTree program identified tetA(58) and nalD genes with sequence similarities of 33.64% and 30.17%, respectively, indicating a low level of homology. These findings suggest that tetracycline resistance in L. buchneri KU200793 is unlikely to have been acquired through horizontal gene transfer, thereby minimizing the risk of resistance gene dissemination. This study underscores the importance of comprehensive safety assessments to evaluate the suitability of L. buchneri KU200793 for probiotic applications. Full article

Background: In occupational science and therapy, occupations are understood as meaningful activities. Satisfaction with the amount and variety of occupations is called occupational balance. The “Occupational Balance in Informal Caregivers” (OBI-Care) questionnaire assesses satisfaction with occupations across three subscales: occupational areas, characteristics, and resilience. In doing so, it also addresses occupational contingency, i.e., the ability to adapt occupations in response to unforeseen events. While previous studies have confirmed its validity in other populations, psychometric properties have not been explored in informal caregivers of stroke survivors. This study aimed to evaluate the construct validity, internal consistency, and suitability of the German OBI-Care for assessing occupational balance for this target group. Methods: A validation study was conducted using data collected via an online survey. Measurement properties of the three subscales were examined using Rasch Rating Scale analysis, exploring construct validity, internal consistency, and interpretability. Construct validity was assessed via dimensionality analyses, item fit, model fit, and threshold ordering. Internal consistency was evaluated using inter-item correlations, item–total correlations, person separation index, and Cronbach’s alpha. Interpretability was examined through floor and ceiling effects. Results: A total of 156 informal caregivers of stroke survivors participated, with 84% (n = 131) women and a median age of 58 (IQR: 49–66) years. All subscales showed unidimensionality with acceptable item and model fit and ordered thresholds. Internal consistency was excellent across all subscales. No floor and ceiling effects were observed. Conclusions: This study demonstrates good construct validity, internal consistency, and interpretability of the German OBI-Care. It is suitable for assessing occupational balance and may help identify and support occupational contingency in informal caregivers of stroke survivors. Full article

The COVID-19 pandemic caused by SARS-CoV-2 has significantly impacted public health worldwide. This study aimed to assess the clinical and diagnostic features of COVID-19 cases in the Tlemcen region, Algeria, and analyze epidemiological trends from January to December 2021. This retrospective study included 68,745 confirmed snapshot active COVID-19 cases from the Public Local Health Care Establishment (EPSP)—University Hospital of Tlemcen. Patients underwent PCR testing and chest CT imaging for clinical evaluation. Data on symptoms, PCR cycle threshold (Ct) values, and CT imaging findings were collected, and statistical analysis was performed to examine the patient’s viral load and lung involvement data. Among 488 confirmed cases, common symptoms included fever, cough, and shortness of breath. PCR Ct values ranged from 15 to 35, and CT imaging revealed widespread lung involvement, with ground-glass opacities being the predominant feature. Epidemiological trends showed a consistent increase in cumulative cases, highlighting sustained transmission throughout the study period. Over the study period, epidemiological surveillance recorded a progressive rise in daily cases, peaking in July with 72 cases, followed by a gradual decline toward the end of the year. The findings underscore the utility of PCR Ct values and CT imaging in evaluating disease severity and monitoring regional case progression. The upward trend in cumulative cases emphasizes the need for ongoing public health measures and diagnostic strategies to manage future outbreaks effectively. Full article

This study presents the results of preliminary documentation and radon tracer investigations conducted at the “Aurelia” Mine in Złotoryja. Measurements of ²²²Rn activity concentrations were carried out between 17 March and 26 August 2023, while terrestrial laser scanning (TLS) for mapping purposes was performed on 16 November 2024. The radon data exhibited a consistently right-skewed distribution, with skewness coefficients ranging from 0.9 to 8.2 and substantial standard deviations, indicating significant data dispersion. Outliers and extreme outliers were identified as key factors influencing average radon activity concentrations from April through August, whereas data from March displayed homogeneity, with no detected anomalies. The average ²²²Rn activity concentrations recorded from March to July ranged from 51.4 Bq/m³ to 65.9 Bq/m³. In contrast, July and August showed elevated average values (75.8 Bq/m³ and 5784.8 Bq/m³, respectively) due to the presence of outliers and extreme values. Upon removal of these anomalies, the adjusted means were 73.8 Bq/m³ and 1003.6 Bq/m³, respectively, resulting in reduced skewness and improved representativeness. These findings suggest that the annual average radon concentrations at the “Aurelia” Mine remain compliant with the regulatory threshold of 300 Bq/m³ set by the Atomic Law Act, with exceedances likely related to atypical or rare geophysical phenomena requiring further statistical validation. August exhibited a significant occurrence of outliers and extreme outliers in ²²²Rn activity concentration data, particularly concentrated between the 13th and 17th days of the month. This anomaly is hypothesized to be associated with geological processes, notably mining-induced seismic events within the LGOM (Legnica–Głogów Copper District) region. It is proposed that periodic transitions between tensional and compressional phases within the rock mass, triggered by mining activity, may lead to abrupt increases in radon exhalation, potentially occurring before or after seismic events with a magnitude exceeding 2.5. Although the presented data provide preliminary evidence supporting the influence of tectonic kinematic changes on subsurface radon dynamics, further systematic observations are required to confirm this relationship. At the current stage, the hypothesis remains speculative but may contribute to the broader understanding of radon behavior in geologically active underground environments. Complementing the geochemical analysis, TLS enabled detailed geological mapping and 3D spatial modeling of the mine’s underground tourist infrastructure. The resulting simplified linked data model—integrating radon activity concentrations, geological structures, and spatial parameters—provides a foundational framework for developing a comprehensive GIS database. This integrative approach highlights the feasibility of combining tracer studies with spatial and cartographic data to improve radon risk assessment models and ensure regulatory compliance in underground occupational settings. Full article

A novel Gram-negative bacterium, designated strain SN16^T, was isolated from a harmful algal bloom (HAB). Strain SN16^T exhibited potent, broad-spectrum algicidal activity against the colony-forming alga Phaeocystis globosa and eight other HAB-causing species, highlighting its potential as a promising candidate for the biological control of HABs. A phylogenetic analysis of 16S rRNA gene sequences placed strain SN16^T within the genus Flagellimonas. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between strain SN16^T and its relatives were 75.4–91.4% and 19.3–44.0%, respectively. These values fall below the established thresholds for species delineation, confirming that SN16^T represents a novel species. A chemotaxonomic analysis revealed its dominant cellular fatty acids to be iso-C_15:0 and iso-C_15:1 G. The major polar lipid was phosphatidylethanolamine, and the primary respiratory quinone was menaquinone-6. Genome mining identified 11 biosynthetic gene clusters (BGCs), including those encoding for terpenes, ribosomal peptide synthetases, and non-ribosomal peptide synthetases. By integrating BGC analysis with the observed algicidal activities, we predicted that pentalenolactone and xiamycin analogues are the likely causative compounds. Based on this polyphasic evidence, strain SN16^T is proposed as a novel species of the genus Flagellimonas, named Flagellimonas algicida sp. nov. This is the first report of Flagellimonas species exhibiting broad-spectrum algicidal activity, including activity against the colonial form of P. globosa—a key ecological challenge in HAB mitigation. Full article

Diabetic neuropathy (DN) is one of the most prevalent complications of diabetes mellitus, affecting a substantial proportion of patients and contributing to progressive sensorimotor dysfunction. Despite its clinical significance, available treatments are often insufficient and associated with undesirable effects. This study aims to evaluate the potential of Morus alba (MA), Angelica archangelica (AA), Valeriana officinalis (VO), and Passiflora incarnata (PI) extracts in ameliorating nociceptive alterations and inflammatory markers in the alloxan-induced diabetic rat model. Male Wistar rats with alloxan-induced DN received oral administration of the plant extracts (200 mg/kg/day) or gabapentin (100 mg/kg/day) for 15 days, the dosage regimen being established based on prior efficacy data in preclinical neuropathy models. Behavioral assessments of thermal and mechanical hypersensitivity were conducted using hot plate, tail withdrawal, von Frey, and Randall–Sellito tests. Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels were quantified in brain and liver homogenates to evaluate neuro-inflammatory responses. All plant extracts produced significant improvements in nociceptive thresholds compared to diabetic control, with the most marked effects observed for MA extract. Pro-inflammatory cytokine levels were significantly reduced in all treatment groups, with MA and AA extracts inducing the most significant reductions in TNF-α and IL-6 concentrations. Computational target prediction and molecular docking analyses revealed that key phytochemicals from the plant extracts may exert antihyperalgesic effects through multi-target modulation, notably via interactions with AAK1, a kinase involved in neuropathic pain signaling. The investigated plant extracts displayed significant antihyperalgesic and anti-inflammatory activities in a rat model of DN. Among them, MA extract revealed the most consistent therapeutic profile, supporting its potential role as a strategy for managing DN. Full article

Interactions between protamines and DNA are essential for the correct structure of human sperm chromatin. Reproductive health can be adversely affected by environmental pollutants like per- and polyfluoroalkyl substances (PFAS). We previously reported that exposure to PFAS in the Veneto region causes alterations in sperm nuclear basic proteins (SNBP), along with reduced seminal antioxidant activity and increased lipoperoxides. This study analysed the protamine-to-histone ratio in SNBP and quantified the extent of DNA damage induced by SNBP in subjects in Veneto with serum perfluorooctanoic acid (PFOA) levels above the reference threshold. We found that all individuals with serum PFOA above the threshold exhibited grade three DNA damage, regardless of the protamine–histone ratio, which was generally altered but consistently shifted toward protamines. This indicate that exposure to PFAS can alter the protamine–histone ratio in these subjects. Moreover, SNBPs from these individuals showed reduced DNA-protective capacity under pro-oxidant conditions, suggesting a role in oxidative damage. To rationalize these effects, in this cross sectional study, we investigated the potential interactions between PFAS and human protamines by molecular docking analyses which showed that PFAS can form stable complexes with DNA through hydrophobic and polar interactions, especially with thymine pyrimidine rings. Further, docking analyses revealed that fluorine atoms in PFAS may interact with guanidinium groups in protamine P1 via electrostatic and van der Waals forces, competing with DNA for binding sites and potentially disrupting chromatin organisation. A ternary PFAS–DNA–protamine adduct may underpin the observed DNA damage. These results suggest that PFAS induce oxidative stress, which could affect male fertility. 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

Salt stress severely constrains agricultural productivity in arid and semi-arid regions. This study evaluated exogenous proline as an osmoprotector in Physalis ixocarpa Brot. (Mexican husk tomato) under salinity. Germination screening identified 75 mM NaCl as a threshold stress level, reducing germination by 38.9% while maintaining seedling viability. Proline pretreatment (30-min imbibition) at 8 mM restored germination to 78% and fresh weight to control levels under salt stress. In vitro experiments revealed that 8 mM proline enhanced chlorophyll content above salt-stressed controls while reducing root length from 9.72 to 5.08 cm, indicating resource reallocation toward photosynthetic protection. Infrared spectroscopy showed characteristic polysaccharide shifts and bands potentially associated with proline incorporation. Gas chromatography–mass spectrometry metabolomics of stem–leaf extracts revealed salt-induced synthesis of nitrogenous osmolytes (such as long-chain amines) and carbohydrate reorganization from α-D-glucopyranoside to β-D-riboside. Proline treatment restored the original carbohydrate profile while generating pyrrolidine derivatives (2.83%), evidence of active proline metabolism. Phenolic antioxidants (e.g., catechol) present in controls were absent under both salt stress and proline treatment, suggesting that proline’s protective mechanism may operate through metabolic regulation of osmolyte pathways and membrane stabilization rather than inducing phenolic antioxidant synthesis. These findings demonstrate proline’s multifaceted protective mechanisms and support its potential application for enhancing salt tolerance in this crop. Full article

Indoor sports facilities face distinctive indoor air quality (IAQ) challenges due to high occupant density, elevated metabolic emissions, and diverse pollutant sources associated with physical activity. This review presents a narrative synthesis of multidisciplinary evidence concerning IAQ in sports environments. It explores major pollutant categories, including carbon dioxide (CO₂), particulate matter (PM), volatile organic compounds (VOCs), and airborne microbial agents, highlighting their sources, behavior during exercise, and associated health risks. Research shows that physical activity can increase PM concentrations by up to 300%, and CO₂ levels frequently exceed 1000 ppm in inadequately ventilated spaces. The presence of semi-volatile organics and bioaerosols further complicates pollutant dynamics, especially in humid and densely occupied areas. Measurement technologies such as optical sensors, chromatographic methods, and molecular techniques are reviewed and compared for their applicability to dynamic indoor settings. Existing IAQ standards across China, the USA, the EU, the UK, and WHO are examined, revealing a lack of activity-specific thresholds and insufficient responsiveness to real-time conditions. Mitigation strategies (e.g., including demand-controlled ventilation, use of low-emission materials, liquid chalk substitutes, and integrated HEPA-UVGI purification systems) are evaluated, many demonstrating pollutant removal efficiencies over 80%. The integration of intelligent building management systems is emphasized for enabling real-time monitoring and adaptive control. This review concludes by identifying research priorities, including the development of activity-sensitive IAQ control frameworks and long-term health impact assessments for athletes and vulnerable users. Full article

Background/Objectives: Chitosan-based films incorporating green-synthesized silver nanoparticles AgNPs) or copper oxide nanoparticles (CuONPs) were developed to compare their selective antimicrobial action for topical applications. While AgNPs are known for broad-spectrum activity, this study hypothesized that CuONPs would exhibit superior, targeted efficacy against the acne-associated bacterium Cutibacterium acnes. Methods: Nanoparticles were synthesized using Camellia sinensis extract and characterized. Antimicrobial activity was evaluated using Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays. Chitosan films containing AgNPs or CuONPs were further tested for selective antimicrobial activity and fibroblast cytocompatibility. Results: AgNPs showed strong activity against Escherichia coli and Staphylococcus aureus (MIC = 15 µg/mL) but were less effective against C. acnes (MIC = 125 µg/mL). In contrast, CuONPs demonstrated selective efficacy against C. acnes (MIC = 62 µg/mL; MBC = 125 µg/mL). When incorporated into chitosan films, AgNPs@CHI inhibited E. coli (35 mm halo) and S. aureus (30 mm), whereas CuONPs@CHI were selectively effective against C. acnes (45 mm). All films preserved fibroblast viability above the 70% ISO 10993-5 threshold. Conclusions: CuONPs@CHI films validated selective anti-C. acnes performance, highlighting their promise for targeted anti-acne therapies, while AgNPs@CHI films served as effective broad-spectrum antimicrobial barriers.revealed that AgNPs were potent against Escherichia coli and Staphylococcus aureus (MIC = 15 µg/mL) but less effective against C. acnes (MIC = 125 µg/mL). Conversely, CuONPs demonstrated a marked selective advantage against C. acnes (MIC = 62 µg/mL; MBC = 125 µg/mL). When incorporated into chitosan films, AgNPs@CHI films inhibited E. coli (35 mm halo) and S. aureus (30 mm), whereas CuONPs@CHI films were selectively effective only against C. acnes (45 mm), confirming the targeted performance. All films maintained fibroblast viability above the 70% ISO 10993-5 cytotoxicity threshold. These findings validate the selective action of CuONPs@CHI films, positioning them as a promising biomaterial for targeted anti-acne therapies, while AgNPs@CHI films serve as effective broad-spectrum antimicrobial barriers. Full article

Background/Objectives: Chronic kidney disease (CKD) requires intensive dietary and lifestyle management, yet patient engagement and access to tailored education remain limited, particularly outside clinical settings. This study describes the development and implementation of NephroGo, and evaluates its usability, user engagement, and perceived acceptability among patients with CKD. Methods: The app was developed based on clinical and dietary guidelines, incorporating personalized nutrient recommendations, dialysis tracking, and educational content. Technically, it features a Django backend, Flutter mobile frontend, and secure cloud-based hosting. User feedback was collected through one-time interviews (n = 10) and a standardized Mobile App Rating Scale (MARS) survey (n = 32). Longitudinal usage data over four years were also analyzed. Results: Initially, NephroGo was downloaded by 204 users, of whom 93.6% were considered active users based on defined behavioral engagement thresholds. Over a four-year period, the app accumulated a total of 1670 downloads. This study focuses on evaluating user engagement, usability, and perceived acceptability of the NephroGo app over a four-year period. Most users were female (52.3%) and aged 30–65. Stage 5 CKD patients and those undergoing peritoneal dialysis (PD) had the highest engagement. The most-used feature was the personalized nutrition calculator, with sodium being the most frequently exceeded nutrient. The average MARS score was 4.09 ± 0.66, with functionality rated highest (4.27 ± 0.74). App ratings were significantly higher among users referred by physicians (p = 0.039). Conclusions: NephroGo offers a scalable digital tool to support dietary management and health monitoring, with potential to complement standard nephrology care in a resource-conscious manner. Full article

In the exploitation of ion-adsorption rare earth ores, the environmental effects of leaching agents are key constraints for green mining. Understanding the release behavior of typical heavy metals from soils under leaching conditions is of great significance. Laboratory column leaching experiments were conducted to systematically investigate the effects of three leaching agents—(NH₄)₂SO₄, Al₂(SO₄)₃, and MgSO₄—as well as varying concentrations of Al₂(SO₄)₃ on the release and speciation transformation of heavy metal Pb in mining-affected soils. The results revealed a three-stage pattern in Pb release—characterized by slow release, a sharp increase, and eventual stabilization—with environmental risks predominantly concentrated in the middle to late stages of leaching. Under 3% (NH₄)₂SO₄ and 3% Al₂(SO₄)₃ leaching conditions, Pb concentrations in soil increased significantly, with a higher proportion of labile fractions, indicating pronounced activation and risk accumulation. Due to its relatively weak ion-exchange capacity, MgSO₄ exhibited a lower and more gradual Pb release profile, posing substantially lower pollution risks compared to (NH₄)₂SO₄ and Al₂(SO₄)₃. Pb release under varying Al₂(SO₄)₃ concentrations showed a nonlinear response. At 3% Al₂(SO₄)₃, both the proportion of bioavailable Pb and the Risk Assessment Code (RAC) peaked, while the residual fraction declined sharply, suggesting a threshold effect in risk induction. All three leaching agents promoted the transformation of Pb in soil from stable to more labile forms, including acid-soluble, reducible, and oxidizable fractions, thereby increasing the overall proportion of active Pb (F1 + F2 + F3). A combined analysis of RAC values and the proportion of active Pb provides a comprehensive framework for assessing Pb mobility and ecological risk under different leaching conditions. These findings offer a theoretical basis for the prevention and control of heavy metal risks in the green mining of ion-adsorption rare earth ores. Full article