Search Results (1,009)

Six river basins of the Upper Indus Basin (UIB), Pakistan, representing glacier-dominated (Hunza and Shyok), snow-dominated (Gilgit, Chitral, and Astore), and rain–snow-mixed (Swat) hydroclimatic regimes are examined to evaluate the suitability of uncorrected CORDEX-SA climate data for hydrological modelling. Data scarcity and complex high-mountain topography make it difficult to obtain reliable inputs, and although bias correction is widely applied to regional climate model (RCM) outputs, it can distort the climate signal and introduce additional uncertainties. This study investigates the extent to which uncorrected outputs from the CORDEX South Asia ensemble can directly simulate daily streamflow in a data-scarce mountainous environment. Nine GCM–RCM combinations, comprising five global climate models and three regional climate models (COSMO-crCLIM-v1-1, REMO2015, and RegCM4-7), are used to drive the HBV-IANIGLA snow–glacier hydrological model over 1981–2005, with calibration from 1981 to 1999 and validation from 2000 to 2005. Several CORDEX-SA members reproduce daily streamflow with acceptable skill without bias correction, but performance is strongly regime-dependent. Snow-dominated basins perform best, followed by glacier-dominated basins, while the rain–snow-mixed basin remains most challenging. COSMO-crCLIM-v1-1 and RegCM4-7 outperform REMO2015 on average. The results indicate that uncorrected CORDEX-SA members can support hydrological assessments in snow-dominated catchments, whereas glacier-dominated and monsoon-influenced basins require additional treatment of climate forcing. Full article

Background/Objectives: Metabolic syndrome (MS) has been demonstrated to be associated with subclinical myocardial dysfunction, which develops in the early stages. It has been hypothesised that traditional echocardiographic parameters may be insufficient in detecting these changes. The frontal QRS-T angle is an electrocardiographic parameter that is easily obtained and that reflects ventricular electrical heterogeneity. This study aimed to examine the relationship between the frontal QRS–T angle and left ventricular myocardial deformation, as assessed by four-dimensional strain echocardiography (4DSE), in patients with MS. Methods: The present cross-sectional study comprised 70 patients diagnosed with MS and 61 healthy individuals matched for age and gender. All participants underwent standard transthoracic and 4DSE examination and 12-lead electrocardiography. The values of global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS) and global area strain (GAS) were analysed. The frontal QRS-T angle was calculated as the absolute difference between the QRS and T axes. The interrelationships between the variables were assessed using correlation and multivariate linear regression analyses. Results: Despite comparable left ventricular ejection fraction (LVEF) between the groups, 4DSE-derived myocardial deformation parameters, including GLS, GCS, GAS, and GRS, were significantly impaired in the MS group. The frontal QRS-T angle was found to be significantly higher in patients diagnosed with MS in comparison to the control group (p < 0.001). A significant correlation was identified between the frontal QRS-T angle and GLS (r = 0.498, p < 0.001). In multivariable linear regression analysis, the frontal QRS–T angle was independently associated with GLS (standardized β = 0.501, p < 0.001). In exploratory receiver operating characteristic (ROC) analysis, the frontal QRS–T angle showed moderate discriminatory ability for GLS-defined impaired myocardial deformation area under the curve (AUC) = 0.720). Conclusions: An increased frontal QRS–T angle in individuals with metabolic syndrome was independently associated with subclinical LV dysfunction despite preserved ejection fraction (EF). These findings suggest that the frontal QRS–T angle may serve as a simple and readily available electrocardiographic marker associated with impaired myocardial deformation, warranting further validation in larger prospective studies. Full article

Essential oils are multicomponent natural products with potential neurobehavioral activity, but integrated comparative studies remain limited. This study compared the essential oils of Satureja brevicalyx, Peperomia dolabriformis, and Rosmarinus officinalis in relation to their chemical profiles, predicted target interactions, preliminary acute oral safety, anxiolytic-like and antidepressant-like effects, antagonist-sensitive behavioral patterns, and exploratory serum biomarkers. Oils were characterized by GC-MS, and their constituents were screened by molecular docking against anxiety-, depression-, sleep-, and stress-related targets. Independent cohorts of male BALB/c mice received oral essential oils (25–100 mg/kg) and were assessed in anxiety-related, depression-related, and locomotor behavioral paradigms, including the elevated plus maze, light–dark box, marble burying, tail suspension, forced swim, and open field tests. Flumazenil and WAY-100635 were used to examine whether the behavioral responses were sensitive to γ-aminobutyric acid type A (GABA-A)/benzodiazepine- and serotonin 1A (5-HT1A)-related pharmacological modulation, respectively. In a preliminary 24-h acute oral toxicity screen, no mortality was observed up to 5000 mg/kg. The three oils produced anxiolytic-like and antidepressant-like effects without reducing spontaneous locomotor activity. Within its experimental block, S. brevicalyx showed the most consistent flumazenil-sensitive anxiolytic-like pattern and FDR-significant reductions in corticosterone and TNF-α, together with increased IL-4. P. dolabriformis showed a broader predicted multitarget docking profile and antagonist-sensitive behavioral attenuation compatible with mixed pathway participation. R. officinalis produced significant but more moderate behavioral effects. WAY-100635 partially attenuated the antidepressant-like effects of all three oils. These findings support differentiated but convergent functional neurobehavioral profiles among the oils. The docking, antagonist, and biomarker results should be interpreted as hypothesis-generating evidence of possible pathway involvement, supporting further validation in chronic stress models, receptor-specific assays, pharmacokinetic studies, and expanded safety evaluations. Full article

The relationship between the morphology of pygidial glands and the chemical nature of their secretions in the tribe Chlaeniini (family Carabidae) has long been recognised. We analysed the morphological features of the pygidial glands and the chemical composition of their secretions in three taxa: Chlaenius (Chlaeniellus) tristis (Schaller, 1783), C. (Chlaenites) spoliatus spoliatus (Rossi, 1792), and C. (Chlaenius) festivus festivus (Panzer, 1796). We examined the morphology of the pygidial glands in all three taxa using bright-field microscopy (BFM) and nonlinear microscopy (NLM). We used gas chromatography–mass spectrometry (GC–MS) and nuclear magnetic resonance (NMR) to analyse the chemical composition of the secretions. We measured and photographed the glands and conducted comparative morphological analyses. We detected a total of 21 chemicals in the pygidial gland secretions of the studied Chlaeniini. We found the highest number of compounds in C. tristis (17), slightly fewer in C. festivus festivus (13), and the lowest number in C. spoliatus spoliatus (seven). Thirteen compounds were new to the tribe Chlaeniini, eight of which were also new to the entire family Carabidae. The most dominant compound in the secretions of all three taxa was 3-methylphenol. We also discussed the taxonomic value of the chemical composition of the pygidial gland secretions. Full article

Urbanization is increasingly limiting daily human exposure to natural forest environments, highlighting the growing importance of urban green infrastructure and nature-based solutions in supporting human health and well-being. Among the mechanisms underlying the beneficial effects of forests, biogenic volatile organic compounds (BVOCs), particularly terpenes, are recognized as key contributors due to their bioactive properties and role in cultural ecosystem services related to human well-being. This study explores the potential of urban and natural trees of Pinus nigra J. F. Arnold to serve as sources of health-relevant BVOCs by examining seasonal and spatial variability in needle terpene profiles. Needle samples were collected from trees growing in an urban park and a protected natural area across three seasons (spring, summer, and autumn), and analyzed using headspace GC/MS. The study was designed as an exploratory assessment aimed at identifying general patterns of terpene variability across contrasting environments. Across all seasons and locations, α- and β-pinene consistently dominated the terpene profile, together accounting for the majority of detected compounds, and showed no significant variation in relation to site or season. In contrast, secondary monoterpenes and sesquiterpenes exhibited greater variability, contributing to context-dependent differences between environments. Despite these variations, the overall terpene composition remained relatively stable, particularly with respect to compounds previously associated with health-related effects. These preliminary findings provide insights into the potential role of Pinus nigra within urban and natural green infrastructure associated with nature-based health-oriented practices. The observed stability of health-related terpenes suggests that urban Austrian pine trees can represent a consistent source of compounds previously associated with health-related effects, although their relevance requires further investigation involving total and individual BVOC emissions measurements and human exposure assessments. Full article

Chemical analysts and archeologists are increasingly interested in organic remains that penetrate the porous structures of ceramic vessels. Fatty acids and archaeological biomarkers are chemical compounds that are particularly important for determining the contents of ceramic vessels. This study involved gas chromatography coupled with mass spectrometry (GC–MS) analysis of organic residues extracted from 56 Neolithic pottery samples found in 18 different settlements in Poland. Fatty acid ratios, including the newly proposed C15:0/C17:0 ratio (pentadecanoic acid/heptadecanoic acid) for the identification of dairy products and archaeological biomarker analysis, were used to determine the possible origin of these residues. The data obtained from the gas chromatography studies were statistically analyzed using principal component analysis (PCA), k-means clustering, and PERMANOVA to determine differences in the diet of the people inhabiting individual settlements. The obtained results allowed us to determine that the Neolithic diet was probably similar in different regions of Poland and throughout different periods of the Neolithic era. However, because of the large difference in variance between the different sample groups, we believe that research should continue and that a larger number of samples per settlement or historical period should be examined. We can conclude that all samples contained residues of mixed animal and plant origin, and the food stored in these vessels was likely subjected to thermal processing. Full article

Background/Objectives: Despite the availability of multiple pharmacological treatment options, up to one-third of patients with depressive disorders fail to achieve adequate symptom relief following first-line antidepressant therapy, representing a major unmet clinical need. Fatty acids—including short-chain (SCFAs), medium-chain (MCFAs), and long-chain polyunsaturated fatty acids (PUFAs)—are increasingly implicated in depression pathogenesis through neuroinflammation, gut–brain axis signaling, and neurotransmitter metabolism, but their potential as predictors of antidepressant response remains largely unexplored. The primary aim is to evaluate whether baseline fatty acid profiles can predict pharmacological antidepressant treatment efficacy. The secondary objective is to assess the association between blood fatty acid profile and clinical presentation of depressive disorders. Methods: Sixty adults diagnosed with depressive disorders (ICD-11) at the initiation of a new antidepressant treatment will be recruited from psychiatric settings. Fasting blood samples collected at baseline will undergo gas chromatographic analysis of fatty acid methyl esters (FAMEs) and GC-MS quantification of SCFAs (acetic, propionic, and butyric acids). Clinical outcomes will be assessed at baseline and at 3, 6, and 12 weeks using the Beck Depression Inventory-II (BDI-II) and the Depression Anxiety Stress Scales (DASS-42). The primary endpoint is the change in BDI-II total score from baseline to week 6. Treatment response, defined as a ≥50% reduction in BDI-II total score at week 6, and remission, defined as a BDI-II score ≤12 at week 6, will be examined as secondary outcomes. Dietary habits, physical activity, quality of life, and anthropometric parameters will be collected as potential confounders. Discussion: This study is among the first prospective investigations to comprehensively characterize the circulating fatty acid spectrum as potential predictors of antidepressant outcomes. Findings may support identification of metabolic phenotypes of depression and contribute to personalized treatment strategies. Full article

Gamma irradiation is one of the techniques widely authorized for the decontamination of dried herbs and spices. Its effect on the functional properties of essential oils, however, remains incompletely characterized. In this study, we examined the impact of gamma irradiation (at 5, 15, and 25 kGy) on the phytochemical composition, antimicrobial activity, antioxidant capacity, and insect-repellent activity of Cymbopogon citratus essential oil. The GC-MS analysis revealed that the citral-dominant chemotype remained stable across all irradiation doses, with geranial and neral constituting approximately 62–63% of the volatile profile. The antibacterial assays were done on five bacterial strains (Staphylococcus aureus, Bacillus subtilis, Streptococcus spp., Pseudomonas aeruginosa, and Klebsiella pneumoniae). Inhibition zones showed no statistically significant differences across irradiation doses (p ≥ 0.05), while MIC (75–100 µg/mL) and MBC (125–150 µg/mL) values remained constant across all doses. DPPH, ABTS, and FRAP antioxidant assays revealed no dose-dependent changes (DPPH IC₅₀: 688–703 µg/mL; ABTS IC₅₀: 18–22 µg/mL; FRAP: 505–517 µg/mL ascorbic-acid equivalents). The essential oil exhibited pronounced repellent activity (87–99%) against adult Tribolium confusum beetles at 0.125 µL/cm², persisting for 24 h and unaffected by irradiation. Molecular docking of the major constituents (geranial, neral, geraniol, and β-myrcene) against key target proteins (3N7H, 3NVY, 4URM, and 8BN6) provided predictive support consistent with the observed activities, indicating plausible molecular interactions rather than confirmed target engagement. In silico ADME and toxicity profiling indicated favorable predicted pharmacokinetic properties and no major in silico toxicity alerts for the four modeled constituents. Taken together, these findings indicate that, under the conditions tested, gamma irradiation at food-decontamination doses produced no major shifts in composition and no statistically detectable changes in the measured bioactivities of C. citratus essential oil. Full article

This study investigated the effect of ethanol on the relative headspace percent composition of evaporative emissions from gasoline at different temperatures using HS-SPME-GC-MS. The results showed that the relative abundance of monoaromatics in the headspace decreased with increasing ethanol content in all tested fuels at all temperatures examined. The paraffins and i-paraffins exhibited a similar decreasing trend in most samples, with reductions more pronounced in E20 (20% ethanol content) than in E10 (10% ethanol content) fuels. The experimental results for the temperature effect on headspace composition were variable: monoaromatics showed slight increases at higher temperatures, whereas paraffins, iso-paraffins, and mononaphthenes generally decreased. However, ethanol addition did not significantly alter these temperature-dependent trends, as similar patterns were observed in both ethanol-blended and ethanol-free fuels. The magnitude of the ethanol effect depended on fuel composition, with the largest reductions in monoaromatic hydrocarbons observed for the high-density gasoline samples. These findings demonstrate that ethanol modifies the relative distribution of hydrocarbon classes in gasoline headspace, with the most pronounced effect being a reduction in monoaromatic hydrocarbons, and highlight the value of class-resolved analysis for understanding fuel evaporation behavior. Full article

This study investigates the decay-like degradation mechanisms of the matrix material in composite insulators, focusing on the pronounced influence of humid environments on partial discharge (PD) characteristics and degradation pathways. A sealed chamber discharge platform was established, integrating PD signal monitoring, surface characterization, and gas chromatography-mass spectrometry (GC-MS) with molecular network analysis to examine the synergistic effects of thermal influences from PD and active atmospheric particles at humidity levels of 0% RH, 50% RH, and 100% RH. Results show that dry conditions favor high-energy, low-repetition-rate discharges, promoting cleavage and recombination of high-bond-energy bonds (e.g., benzene rings and (α)C–O), yielding primarily long-chain carboxylic acids (C9 and above). In contrast, humid conditions shift to low-energy, high-repetition-rate discharges, with water vapor decomposition generating highly oxidizing hydroxyl radicals (·OH). These facilitate selective scission of lower-bond-energy (β)C–O bonds and deep oxidation, significantly increasing short-chain dicarboxylic acids—especially oxalic acid—whose acidity and water solubility are nearly an order of magnitude higher than in dry environments, becoming the dominant acidic products. The work demonstrates that many PD-generated organic acids act as intrinsic corrosive agents in insulating systems, independent of ambient nitric acid. This elucidates, at the reaction pathway level, how high humidity modulates PD to enhance corrosive acid production, providing a microchemical basis for understanding regional decay-like failure patterns in composite insulators. Full article

Soil is prone to structural degradation under water infiltration, and the combined effects of dry density and salinity further complicate its hydraulic conductivity and drying shrinkage behavior. However, previous studies have primarily focused on single factors, and the interactive mechanisms between compaction state and salinity remain poorly understood. To investigate the hydraulic conductivity and drying shrinkage behavior of soil under different dry densities and salinity levels, this study examined three dry densities (1.30, 1.35, 1.45 g/cm³) and four NaCl contents (0, 0.5%, 2%, 6%). Saturated hydraulic conductivity (ks) and drying shrinkage were systematically measured. The results indicate that dry density is the primary factor controlling pore structure evolution, ks and drying shrinkage behavior. Increasing dry density markedly reduced porosity (up to 15.95%), ks (by 57.14–92.91%), and drying shrinkage. In contrast, salinity exhibited non-monotonic, density-dependent effects. Salts increased porosity through electrochemical interactions and crystallization-induced pore support, but their effects on ks and drying shrinkage displayed threshold and reversal behavior. These coupled effects demonstrate strong nonlinearity and density dependence, providing a mechanistic basis for compaction optimization and the stability assessment of soil under saline conditions. Full article

Background/Objectives: Lavandula cariensis species is cultivated uncommonly in the western region of Turkey. The colloquial appellations avayianos, karabasi, and myra are used to refer to the L. cariensis plant. The essential oil of L. cariensis was studied for its potential antiglaucoma, antioxidant, antidiabetic, and acetylcholinesterase inhibitory effects. Methods: The inhibitory effect of the essential oil of L. cariensis on the acetylcholinesterase (AChE), carbonic anhydrase II (CA II), and α-amylase enzymes was determined. Therefore, chemical profiles of L. cariensis’ essential oil were identified using Gas Chromatography Mass Spectrometry (GC-MS) and as Chromatography with Flame Ionization Detection (GC-FID) analyses. Results: Camphor (39.73%), fenchone (19.49%), exobornyl acetate (6.81%), camphene (5.49%), and eucalyptol (5.49%) were the most abundant compounds in L. cariensis essential oil. Radical scavenging effect of the essential oil of L. cariensis was examined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC₅₀: 231.0 ± 0.094 μg/mL) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) (IC₅₀: 7.45 ± 0.013 μg/mL) radicals. Also, the ferric ions (Fe³⁺), cupric ions (Cu²⁺), and Fe³⁺-2,4,6-tri(2-pyridyl)-S-triazine (TPTZ) complex reducing capabilities were studied. Additionally, essential oil of L. cariensis indicated a comparable level of inhibition towards hCA II (IC₅₀: 276.42 μg/mL), AChE (IC₅₀: 14.22 μg/mL), and α-amylase (IC₅₀: 475.63 μg/mL) enzymes. Conclusions: The evaluation of the antioxidant capabilities and enzyme inhibition profiling of the essential oil of L. cariensis will be made possible by this comprehensive study, which serves as a springboard for further research. The essential oil of L. cariensis demonstrated enzyme-inhibitory activities against target enzymes associated with Alzheimer’s disease, diabetes, and glaucoma. Also, this study’s in vitro inhibition suggests promising prospects. Full article

Madhuca indica J.F.Gmel. holds significant economic and industrial value due to its applications in traditional and modern medicine. Its oil is especially important for biodiesel production, owing to its high acid value and suitability as a non-edible feedstock. However, propagation is difficult due to low seed germination, seed recalcitrance, and poor rooting of stem cuttings, limiting large-scale multiplication through conventional methods. To address these limitations, a regeneration protocol using nodal explants was developed. Murashige and Skoog (MS) medium augmented with BA (5.0 µM) and NAA (0.5 µM) produced a maximum of 7.10 ± 0.11 shoots per explant with an average shoot length of 4.53 ± 0.22 cm after six weeks. Rooting was achieved on half-strength medium supplemented with IBA (1.0 µM), resulting in 4.83 ± 0.17 roots per shoot and a root length of 4.50 ± 0.20 cm. In vitro-derived plants were successfully acclimatised in Soilrite with an 82.3% survival rate. The explants were derived from aseptic seedling material, representing juvenile rather than mature elite donor sources. Direct shoot bud development was verified by histological examination. Within the resolution of the employed marker systems, no polymorphism was found utilising RAPD and ISSR markers. SEM showed similar leaf surface characteristics, and physiological and biochemical studies were carried out throughout acclimatisation. A partial overlap in metabolite composition with qualitative and relative quantitative differences between mother and in vitro-derived plants was shown by GC–MS-based profiling. Overall, the study establishes a reproducible regeneration system for M. indica, providing a basis for further optimisation and conservation-oriented applications. Full article

Background/Objectives: Mosquitoes, including Culex quinquefasciatus and Aedes aegypti, are important vectors of dengue fever, Zika virus, West Nile virus, Japanese encephalitis virus, Eastern equine encephalitis virus, etc. Biological control has always been urgent in mosquito prevention due to resistance developing to synthetic insecticides and environmental toxicity by insecticides. Methods: The leaf essential oil of Mosla. chinensis was isolated, and major components were identified via GC-MS, followed by olfactory behavior assays to evaluate its repellent activity against C. quinquefasciatus. Additionally, the odorant-binding protein 1 and odorant-binding protein 2 (CquiOBP1-2) genes were prokaryotically expressed, and their fluorescence competitive binding activities with the active components of essential oils were examined. Results: The bioassays indicated this essential oil greatly repels C. quinquefasciatus, which will significantly protect people against vector-borne diseases. In the fluorescence competitive binding experiments, the CquiOBP1-2 proteins exhibit great binding capacities to volatile components, including Citronellal, Citronellol, Geraniol, Limonene and Isopulegol. Furthermore, the behavioral experimental results also indicate that the mixture of these five ligand compounds has an obvious repellent effect on mosquitoes, highlighting that they may be applied as potential mosquito repellent agents. Moreover, molecular docking and site-directed mutation analysis further confirm Phe123 and Gln77 are both key amino acid residues of CquiOBP1-2 proteins involved in the olfactory recognition of repellent ligand compounds from M. chinensis essential oil. Conclusions: The behavioral experimental verification and the exploration of olfactory molecular mechanisms are helpful to promote the biological control of plant essential oils in mosquito pests. Full article

Polishing enhances the appearance and market competitiveness of rice. To better understand the effect of polishing on rice flavor, volatile flavor compounds in polished rice (PR), unpolished rice (UR), cooked polished rice (CPR), and cooked unpolished rice (CUR) were examined using headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS). The results revealed fourteen volatile flavor compounds displayed significant differences in abundance, with eight of these compounds potentially contributing to the overall flavor profile based on their volatility and reported odor characteristics. Among these compounds, only eicosane and hexanal were detected in uncooked rice, whereas acetophenone, hexadecanol, dodecane, and octadecane were unique to CUR. Four compounds were associated with aroma notes reminiscent of flowers, wax, and almond, among others. However, nonanal and nerol were common in both cooked rice samples, and they may contribute to a sweet-like aroma in cooked rice. These findings illuminate the changes in volatile composition, offer insights to prevent over-polishing, and inspire further research toward producing rice with potentially improved aroma profiles. Full article