Stress Index Research Articles

Antarctic Krill Euphausia superba Oil Supplementation Attenuates Hypercholesterolemia, Fatty Liver, and Oxidative Stress in Diet-Induced Obese Mice.

Several Previous studies indicate that consuming krill oil may aid in reducing hypercholesterolemia and improving cholesterol metabolism. Therefore, our study was designed to investigate the effectiveness of Antarctic krill oil (Euphausia superba) (ESKO) in combating obesity and lowering fat/lipid/cholesterol levels. The study aimed to investigate the molecular docking model targeting 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) using ESKO-derived eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and astaxanthin. In this study, histological alterations in the liver of the obesity model (ICR male mouse), obesity-related or antioxidant markers in both liver and serum, the molecular mechanisms in HepG2 cells and liver tissue, and HMGCR activity were analyzed. Our findings revealed that a high-fat diet (HFD) significantly led to increased oxidative stress, obesity-related indicators, and cardiovascular-associated risk indices. However, ESKO effectively mitigated HFD-induced oxidative stress, fat accumulation, and the suppression of low-density lipoprotein receptor (LDLR) or activation of related molecular pathways. This was achieved through improvements in metabolic parameters, including CD36/liver X receptor α (LXRα)/sterol regulatory element-binding protein 1c (SREBP1c), proprotein convertase subtilsin/kexin type 9 (PCSK-9), and HMGCR, ultimately ameliorating HFD-induced hypercholesterolemia and obesity. These beneficial findings indicate that ESKO might have significant potential for preventing and treating obesity-related disorders.

Effects of Oregano Aromatic Water (Oreganum onites L.) Supplementation on Diets of Lactating Dairy cows on Milk Production Performance, Metabolic Health and Antioxidative Defense Mechanism

This study aimed to validate the effect of oregano aromatic water (OAW) on blood parameters, oxidative stress, and production and composition of milk when used as a feed additive. Thirty lactating Holstein cows (average 570 kg), average 74 days in milk and 2.44 lactation number, were randomly divided into three groups for a period of 60-days. These groups included: (G1) control ration, (G2) control ration + OAW (10 mg/kg of DM), (G3) control ration + OAW (20 mg/kg of DM). Milk production (MP) were unaffected by OAW doses (P>0.05). The supplementation of OAW did not affect the milk composition, and somatic cell count (SCC) (P>0.05). OAW supplementation did not affect blood biochemical values except ketone and glucose. The glucose value increased as the ketone decreased with OAW supplementation (P<0.05). The hematological blood values were not found to be significant. OAW significantly decreased Total oxidant capacity (TOC) and oxidative stress index (OSI) while increasing Total antioxidant capacity (TAC). The current study's findings indicated that OAW can be used as a feed additive to improve cow health and milk production.

Effect of heat stress, determination of temperature-humidity index

Relevance. Increased values of temperature and relative humidity of the external environment lead to negative consequences for the animal body, forcing the thermoregulation processes to be turned on. These mechanisms allow the animal organism to adapt to new environmental conditions at the expense of productivity. In these cases heat stress is observed. It is established that its manifestation is observed after 17 hours and there is a possible decrease in productivity by 35–40%. To identify the effect of heat stress, accurate determination of temperature-humidity index (THI) is necessary.Methods. The materials and methods contain the most common formulas for determining the temperature and humidity index. The equipment and software package used for the research are presented.Results. A graph of the results of South Korean studies is presented to compare the effects of heat stress on productivity. The results and discussions display a modernized formula for determining the heat stress index and figures showing the level of heat stress at different temperature and relative humidity levels.

Characterizing heatwaves based on land surface energy budget

Heat extremes pose pronounced threats to social-ecological systems and are projected to become more intense, frequent, and longer. However, the mechanisms driving heatwaves vary across heatwave types and are not yet fully understood. Here we decompose perturbations in the surface energy budget to categorize global heatwave-days into four distinct types: sunny–humid (38%), sunny-dry (26%), advective (18%), and adiabatic (18%). Notably, sunny-dry heatwave-days decrease net ecosystem carbon uptake by 0.09 gC m−2 day−1 over harvested areas, while advective heatwave-days increase the thermal stress index by 6.20 K in populated regions. In addition, from 2000 to 2020, sunny-dry heatwaves have shown the most widespread increase compared to 1979 to 1999, with 67% of terrestrial areas experiencing a doubling in their occurrence. Our findings highlight the importance of classifying heatwave-days based on their underlying mechanisms, as this can enhance our understanding of heatwaves and improve strategies for heat adaptation.

Effects of dietary fermented mealworm larvae and stocking density on performance, blood stress indicator and intestine parameters of broilers

The present study was conducted to evaluate the effects of the supplementation of defatted mealworm larvae meal fermented with probiotics as a new antibacterial feed additive to the diet of broilers reared under normal- (NSD) and high- (HSD) stocking density on growth performance, blood and slaughtering parameters, microorganism content and morphology of ileum and short-chain fatty acids content of ceca. A total of four hundred and fifty one-d-old Ross 308 male broiler chicks were randomly distributed into six groups of similar mean weight, each containing five replicates. Experimental treatments consisted of a 2 x 3 factorial arrangement with two levels of stocking density (12 birds/m2 as NSD and 18 birds/m2 as HSD) and three different mash diets: CONT- a corn-soybean meal-based diet containing no fermented defatted mealworm larvae meal (FDM) (0%); FDMLP- the diet obtained by supplementing DM fermented with Lactobacillus plantarum to the CONT diet (0.4%); FDMLB- the diet obtained by supplementing DM fermented with Lactobacillus brevis to the CONT diet (0.4%). HSD significantly decreased the growth performance except feed conversion ratio (FCR), carcass yields (CYs), Lactobacillus spp. content and villus height (VH) and villus surface area (VSA) of ileum and short-chain fatty acids (SCFAs) concentrations of ceca, but, increased the blood heterophil/lymphocyte (H/L) ratio and Escherichia coli content and crypt depth (CD) of ileum of broilers compared to NSD. The FDMLP and FDMLB diets significantly improved the FCR and increased final body weight (BW), BW gain, Lactobacillus spp. content and VH and VSA of ileum and SCFAs concentrations of ceca, however, reduced the blood H/L ratio and Escherichia coli content and CD of ileum of broilers when compared to the CONT diet. In conclusion, FDMLP and FDMLB can be utilized as new antibacterial feed additives in broiler diets regardless of stocking density.

COMPARISON OF NEUTROPHILAND LYMPHOCYTE (N/L) RATIO IN SAPERAAND CROSSBRED ETAWAH GOATS IN SAYEGAN, SLEMAN, YOGYAKARTA AND ITSSOROUNDING AREA

Neutrophil and lymphocyte ratio (N/L) can be used as a chronic stress indicator inanimal. Increase of N/L ratio indicates stress in animal that marked by neutrophilia and lymphopenia. The study was aimed to determine the comparison of N/L ratio in Sapera an Ettawah crossbreed goats.The samples of this study were obtained from 126 Sapera goats and 99 Ettawah cross breed goats with various physiological condition status (rams, pregnant ewes, nanny goats, ewes, young rams, young ewes, and lactating goats)that are clinically healthy from farm in Seyegan, Sleman, and its surrounding. Blood samples were taken through jugular vein in the morning, the blood smear were made to calculate leukogram. The average calculation results of N/L ratio in Sapera goat group is 0.55±0.,57and Ettawah crossbreed goat group is 0.47±0.44.The results of the statistical analysis using the One-Way Analysis of Variance test showed an insignifi cant difference in the N/L ratio (p > 0.05) between groups of Sapera and Ettawah crossbreed goats. It can be concluded there was no significant influence of the breed and physiological status difference in Sapera and Ettawah crossbreed goat's blood N/L ratio.

Effect of Lead, Cadmium, and Their Combination on the Heart Rate Regulation in Nonlinear Rats.

We studied heart rate variability (HRV) and the concentrations of heavy metals in the heart tissue after 14-fold peroral administration of heavy metal salts: lead acetate (50 mg/kg), cadmium chloride (5 mg/kg), and their combination. After administration of lead, its concentration in the myocardium exceeded the control values by 1.2 times or did not change in case of combination with cadmium; after administration of cadmium, its concentration in the myocardium exceeded the control value by 6.1 times or by 2 times after combined administration. After lead administration, a moderate increase in HR, low values of stress and centralization indices, and an increase in the power in all ranges of the HRV spectrum were recorded. After cadmium intoxication, a tendency to a decrease in heart rhythm variability, a moderate increase in HR, stress and centralization indices, and an increase in the contribution of VLF waves in the HRV spectrum were observed. After combined administration, a pronounced increase in HR and stress index and a moderate increase in the centralization of heart rhythm control were recorded, which was similar to changes in HRV observed after administration of cadmium alone. In the experiment, the concentration of cadmium in the myocardium increased to a much greater extent than the concentration of lead. After lead administration, the autonomous type of regulation persisted and parasympathetic influences increased. Cadmium apparently acts as a stress factor and increases the role of sympathoadrenal influences and central ergotropic structures in the heart rhythm regulation.

Comparative study of the photosynthetic efficiency and leaf structure of four Cotoneaster species

Plants belonging to the genus Cotoneaster can be valuable sources of phytochemicals with potential therapeutic properties. The natural habitats of most of these species are situated in Asia, Africa and southern Europe. Introducing them into other climatic conditions could expose them to abiotic and biotic stresses, affecting their bioactive properties. The aim of this study was to assess and compare the performance of four non-native Cotoneaster species (C. roseus, C. hissaricus, C. hsingshangensis, C. nebrodensis) grown in eastern Poland in terms of leaf morphology, anatomy, and efficiency of the photosynthetic apparatus in relation to lipid peroxidation level, being an indicator of oxidative stress. Photosynthetic pigments concentration and chlorophyll a fluorescence parameters were used to evaluate the photosynthetic capacity. The morphological and anatomical analysis of leaves did not show any anomalies or stress symptoms. Cotoneaster roseus was characterized by the highest chlorophyll concentration, viability index (Rfd) and a moderate lipid peroxidation level. On the other hand, the lowest values of photochemical quenching (qP), maximum fluorescence (Fm), Rfd, and quantum yield of the photosystem II (QY) observed for C. nebrodensis might indicate an inferior efficiency of the photosynthetic apparatus in this species; however, it demonstrated the lowest lipid peroxidation level. Nevertheless, the content and proportion of the photosynthetic pigments as well as overall chlorophyll a fluorescence parameters and lipid peroxidation levels indicate a good physiological condition of all examined plants. The observed differences between the species may be rather species specific and genetically established and not indicate their sensitivity to non-native growth conditions. This is the first report about the physiological parameters of the four Cotoneaster species, proving they are well adapted to growth in the climatic conditions of central Europe providing thus a raw material with potential for pharmaceutical applications.

Dietary Restriction of Advanced Glycation End-Products (AGEs) in Patients with Diabetes: A Systematic Review of Randomized Controlled Trials.

Advanced Glycation End Products (AGEs) are formed through non-enzymatic reactions between reducing sugars and proteins, nucleic acids or lipids (for example through hyperoxidation). In diabetes, elevated glucose levels provide more substrate for AGEs formation. AGEs can also be ingested through the diet from foods cooked at high temperatures, or containing much sugar. The present work aimed to review all published randomized controlled trials (RCT) on low-dietary AGE (L-dAGEs) interventions in patients with diabetes. Pubmed, Scopus and Cochrane databases were searched (until 29 February 2024) with appropriate keywords (inclusion criteria: RCT, patients with diabetes, age > 18 years, outcomes related to inflammation, glucose, and lipids; exclusion criteria: non-RCTs, case-series, case reports and Letter to the Editor, or animal studies). The present review was registered to the Open Science Framework (OSF). From 7091 studies, seven were ultimately included. Bias was assessed with the updated Cochrane Risk of Bias tool. A reduction in circulating AGEs was documented in 3/3 studies. No particular differences were documented in glycemic parameters after a L-dAGEs diet. Reductions in glucose levels were observed in one out of six studies (1/6), while HbA1c and HOMA did not change in any study (0/6 and 0/3, correspondingly). Lipid profile also changed in one out of four studies (1/4). More consistent results were observed for oxidative stress (beneficial effects in 3/3 studies) and inflammatory markers (beneficial effects in 4/4 studies). Other athero-protective effects, such as adiponectin increases, were reported. Limitations included the small sample size and the fact that dietary and physical activity habits were not considered in most studies. In conclusion, a L-dAGEs pattern may minimize AGEs accumulation and have beneficial effects on oxidative stress and inflammation indices, while its effects on glycemic and lipemic parameters are inconsistent and modest in patients with diabetes.

Transplantation of human umbilical cord-derived mesenchymal stem cells improves age-related ovarian functional decline via regulating the local renin–angiotensin system on inflammation and oxidative stress

BackgroundAge-related reproductive aging is a natural and irreversible physiological process, and delaying childbearing is increasingly common all over the world. Transplantation of mesenchymal stem cells (MSCs) is considered a new and effective therapy to restore ovarian function, but the relevant mechanisms remain unclear. Recently, it has been found that there is a local Renin–angiotensin system (RAS) in human ovary and it plays a key role.MethodsAfter collecting follicular fluid from women who received oocyte retrieval for pure male factor infertility, the level of RAS components in it were detected, and the correlation analysis by linear regression. Then, the in vivo experiments on female C57BL/6 mice were designed to measure ovarian function, and the transcription and translation levels of RAS pathway were detected by molecular biology methods. Moreover, the role of RAS in regulating inflammation and oxidative stress in the co-culture system were explored in in vitro experiments on KGN cells.ResultsFirst, a total of 139 samples of analyzable follicular fluid were obtained. The local RAS of ovary, which is independent of systemic RAS (P > 0.05), is affected by age (Pearson r < 0, P < 0.05) and related to ovarian function, inflammation, oxidative stress indexes and assisted reproduction laboratory outcomes (P < 0.05). Next, the ovary/body weight of aging mice decreased significantly and serum sex hormones levels changed significantly (P < 0.01). The number of functional follicles decreased, while the atresia follicles increased (P < 0.05). After MSCs transplantation, all the above measures have been partially recovered (P < 0.05). Although several RAS components in aging ovary changed, MSCs only improved the expression level of AT1R (P < 0.05). Furthermore, the secretion ability and mitochondrial membrane potential of aging KGN cells decreased, while the intracellular ROS level and the aging cells ratio increased (P < 0.01). All the above measures have been partially recovered when co-cultured with MSCs (P < 0.05). After Ang(1–7) were added into the co-culture system, the above have been more significantly restored compared with Ang II (P < 0.05). Nevertheless, there was no statistical difference in estradiol level no matter which one was added (P > 0.05).ConclusionsTogether, our findings indicate that a novel possible mechanism to explain how stem cells restore age-related ovarian functional decline.

Sociodemographic and Clinical Profile of 915 Autistic Preschoolers Engaged in Intensive Early Intervention in Australia.

There is a paucity of information on the sociodemographic and clinical characteristics of autistic children with high support needs. This study aims to address this gap by profiling a cohort of 915 children enrolled in full-time early intervention for autism spectrum disorder (ASD) in Australia between 2012 and 2024. Intake questionnaires assessed the sociodemographic characteristics of families entering the service. Clinical measures included the Autism Diagnostic Observation Schedule (2nd ed.), Mullen Scales of Early Learning, and Vineland Adaptive Behaviour Scale (2nd and 3rd eds.). Family measures included the Parenting Stress Index (4th ed., Short Form) and Autism Family Experience Questionnaire. Results indicated a male to female ratio of 3.8:1, clear delays from the age of first concern to diagnosis and intervention, and notable proportions of culturally diverse families. While clinical data indicated cognitive and adaptive deficits beyond findings in other ASD studies, measures of stress and family experiences were comparable to other autism literature. By reporting these findings, this study aims to facilitate a more informed, tailored and nuanced approach to addressing the unique challenges faced by autistic children with high support needs. The scope and limitations of this cohort are discussed.

Integrating observational and modelled data to advance the understanding of heat stress effects on pregnant subsistence farmers in the gambia

Studies on the effect of heat stress on pregnant women are scarce, particularly in highly vulnerable populations. To support the risk assessment of pregnant subsistence farmers in the West Kiang district, The Gambia we conducted a study on the pathophysiological effects of extreme heat stress and assessed the applicability of heat stress indices. From ERA5 climate reanalysis we added location-specific modelled solar radiation to datasets of a previous observational cohort study involving on-site measurements of 92 women working in the heat. Associations between physiological and environmental variables were assessed through Pearson correlation coefficient analysis, mixed effect linear models with random intercepts per participant and confirmatory composite analysis. We found Pearson correlations between r-values of 0 and 0.54, as well as independent effects of environmental variables on skin- and tympanic temperature, but not on heart rate, within a confidence interval of 98%. Pregnant women experienced stronger pathophysiological effects from heat stress in their third rather than in their second trimester. Environmental heat stress significantly altered maternal heat strain, particularly under humid conditions above a 50% relative humidity threshold, demonstrating interactive effects. Based on our results, we recommend including heat stress indices (e.g. UTCI or WBGT) in local heat-health warning systems.

Prediction of number of generations of serpentine leaf miner, &lt;i&gt;Liriomyza trifolii&lt;/i&gt; (Burgess) (Agromyzidae: Diptera) in India assessed by CLIMEX under climate change scenario

The serpentine leaf miner, Liriomyza trifolii, is an invasive pest that affects plants, causing damage to the leaves and reducing crop yield. Number of generations of serpentine leaf miner was assessed under current and expected future climate change scenarios. The assessment was done for Representative Concentration Pathway (RCP 8.5) future climate change scenario in India. L. trifolii would have had 16-19 generations, in base line and 17-24 in 2050-time frame under future climate change in Andhra Pradesh conditions. Under Arunachal Pradesh conditions, it would have had 6-14 generations in base line and is expected to complete the same number of generations in 2050, scenario. Under Sikkim conditions 3 - 4 and 5 number of generations were assessed for present and future climate change scenario. Suitability of the localities was expressed in terms of Ecoclimatic index (EI) ranging from 0 to &gt; 20 by combining the interaction effect of various stress indices and growth indices for the development of L. trifolii. It was observed that in temperate areas the pest incidence may increase in future, in contrast to the decreasing trend in areas where already the prevailing temperatures are near upper thresholds. It is therefore expected that number of generations of L. trifolii would increase with the rising temperatures under climate change situations.

Relationship of chronic low back pain intensity with functional activity, stress and quality of life in working-age adults

Background. Low back pain (LBP) is a global problem in the modern world. A detailed study of the relationship between pain intensity and the indicators with which it may be associated will allow optimising approaches to the treatment and rehabilitation of patients with chronic LBP. The purpose was to eva­luate the relationship between the intensity of chronic LBP and indicators of functional activity, stress and quality of life in subjects of working age. Materials and methods. A survey was conducted among 159 persons aged 18-65 years with LBP lasting more than 3 months. Using a Google-form, the participants were given a questionnaire that included socio-demographic, anthropometric characteristics, lifestyle data, bad habits, physical activity (PhA) and stress levels, quality of life, and impairment. The intensity of pain was measured at the first visit to a PhRM doctor using a visual analogue scale (VAS). Results. The study involved 159 patients, 65.7 % women and 34.3 % men, with a mean VAS pain intensity of 46.5 ± 18.6 mm. A weak positive correlation was found between pain intensity and age (r = 0.30, p &lt; 0.001), but no significant relationship was found between pain intensity and anthropometric parameters. Subjects who smoke, have insufficient PhA and sleep disturbance had higher pain intensity scores (57.6 ± 15.2 mm (p = 0.04), 49.0 ± 18.8 mm (p = 0.12), 49.7 ± 19.9 mm (p = 0.002), respectively). Sitting time more than 6 hours had significant associations with pain intensity (p &lt; 0.001). A weak positive correlation was found between pain intensity on the VAS scale and stress le­vel (r = 0.24, p = 0.002), a moderate positive correlation between pain intensity and impairment (r = 0.36, p &lt; 0.001) and a mo­derate negative correlation between quality of life and pain intensity. ­Conclusions. There was a significant association between pain intensity and age, smoking, sleep disturbance, sedentary work for more than 6 hours, higher stress levels, impaired functioning and lower quality of life.

Effects of smoking on local and systemic oxidative stress markers in individuals with periodontitis

Aim: This study aimed to assess the effects of smoking on systemic and local oxidative stress markers in patients with periodontitis. Methods: A total of 72 patients with periodontitis [38 smokers (S +P+), 34 non-smokers (S-P+)] and 54 periodontally healthy individuals [28 smokers (S+P-), 26 non-smokers (S-P-, control)] were included. After clinical measurements and samplings, the cotinine level, total antioxidant capacity (TAOC), total oxidative status (TOS), and malondialdehyde (MDA) level in the serum and saliva were determined, and the oxidative stress index (OSI) was calculated. Kruskal-Wallis and Mann-Whitney U tests were used for multiple and pairwise comparisons. Correlations were analyzed using Pearson correlation coefficient. P&lt;0.05 was considered statistically significant. Results: Smoking and periodontitis decreased the serum and salivary TAOCs and increased the TOS, MDA level, and OSI. The smokers with periodontitis had the lowest TAOC and the highest TOS, MDA level, and OSI, while the controls had the highest TAOC and the lowest TOS, MDA level, and OSI. The systemic and local effects of smoking seemed more pronounced than those of periodontitis in the oxidative stress study, but no significant difference was identified between the smoking (S+P-) and periodontitis (S-P+) groups. The clinical parameters and oxidative stress markers showed both substantial positive and negative relationships in all groups (p&lt;0.01). Conclusions: It can be concluded that smoking and periodontitis (S+P+) are associated with a decrease in serum and salivary TAOCs and an increase in TOS, MDA levels, and OSI. Smoking has a similar effect as periodontitis on local and systemic oxidative stress, and oxidative stress caused by smoking may be a significant factor in the pathophysiology of periodontitis.

Optimizing wheat supplementary irrigation: Integrating soil stress and crop water stress index for smart scheduling

A two-year field experiment was conducted to integrate soil moisture stress with the Crop Water Stress Index (CWSI) for optimizing irrigation in winter wheat (Triticum aestivum L.) under varying irrigation regimes. The study took place at the Water Technology Centre (WTC-02) of ICAR-IARI, New Delhi, where the climate shows a blend of monsoon-influenced humid subtropical and semi-arid conditions. Using a randomized block design (RBD), five irrigation treatments were applied: full irrigation and deficit irrigation (DI) at 15 %, 30 %, 45 %, and 60 % levels. Canopy and ambient air temperature data, along with vapor pressure deficit (VPD), were recorded using a developed integrated sensing device to empirically determine the lower baseline equations and upper threshold for CWSI computation at pre-heading and post-heading stages. The slope (m), intercept (c) of the lower baseline equation, and upper threshold (UL) for pre-heading and post-heading were found: m: −1.94, c: −1.33, UL: 1.92°C and m: −1.30, c: −2.37, UL: 2.0°C, respectively. Results showed that increasing water deficit levels led to significant reductions in grain yield, biomass production, and harvest index. A strong negative correlation (R² = 0.95 and 0.93) between mean seasonal CWSI and yield attributes highlighted the utility of CWSI in yield prediction under varying irrigation regimes. It is recommended to schedule irrigation based on the CWSI approach when CWSI ≥0.35 for optimum wheat yields. Integrating CWSI with soil moisture stress provides valuable real-time insights into crop water status, enabling more precise and smart irrigation scheduling.

Analyzing the Spatiotemporal Dynamics of Drought in Shaanxi Province

Drought, as a natural disaster with wide-ranging impacts and long duration, has an adverse effect on the global economy and ecosystems. In this paper, four remote sensing drought indices, namely the Crop Water Stress Index (CWSI), Vegetation Supply Water Index (VSWI), Temperature Vegetation Dryness Index (TVDI), and Normalized Difference Water Index (NDWI), are selected for drought analysis. The correlation analysis is carried out with the self-calibrated Palmer Drought Severity Index (sc-PDSI), and based on the optimal index (CWSI), the spatiotemporal characteristics of drought in Shaanxi Province from 2001 to 2021 were studied by SEN trend analysis, Mann–Kendall test, and a center of gravity migration model. The results show that (1) the CWSI performs best in drought monitoring in Shaanxi Province and is suitable for drought studies in this region. (2) Drought in Shaanxi Province shows a decreasing trend from 2001 to 2021; the main manifestation of this phenomenon is the decrease in the occurrence of severe drought, with severe drought covering less than 10% of the area in 2010 and subsequent years. The most severely affected regions in the province are the northern Loess Plateau region and Guanzhong Plain region. In terms of the overall trend, only 0.21% of the area shows an increase in drought, primarily concentrated in the Guanzhong Plain region and the outskirts of the Qinling–Bashan mountainous region. (3) Drought conditions are generally improving, with the droughts’ center of gravity moving northeastward at a rate of 3.31 km per year. The results of this paper can provide a theoretical basis and a practical reference for drought control and decision-making in Shaanxi Province.

A Coupled Model for Forecasting Spatiotemporal Variability of Regional Drought in the Mu Us Sandy Land Using a Meta-Heuristic Algorithm

Vegetation plays a vital role in terrestrial ecosystems, and droughts driven by rising temperatures pose significant threats to vegetation health. This study investigates the evolution of vegetation drought from 2010 to 2024 and introduces a deep-learning-based forecasting model for analyzing regional spatial and temporal variations in drought. Extensive time-series remote-sensing data were utilized, and we integrated the Temperature–Vegetation Dryness Index (TVDI), Drought Severity Index (DSI), Evaporation Stress Index (ESI), and the Temperature–Vegetation–Precipitation Dryness Index (TVPDI) to develop a comprehensive methodology for extracting regional vegetation drought characteristics. To mitigate the effects of regional drought non-stationarity on predictive accuracy, we propose a coupling-enhancement strategy that combines the Whale Optimization Algorithm (WOA) with the Informer model, enabling more precise forecasting of long-term regional drought variations. Unlike conventional deep-learning models, this approach introduces rapid convergence and global search capabilities, utilizing a sparse self-attention mechanism that improves performance while reducing model complexity. The results demonstrate that: (1) compared to the traditional Transformer model, test accuracy is improved by 43%; (2) the WOA–Informer model efficiently handles multi-objective forecasting for extended time series, achieving MAE (Mean Absolute Error) ≤ 0.05, MSE (Mean Squared Error) ≤ 0.001, MSPE (Mean Squared Percentage Error) ≤ 0.01, and MAPE (Mean Absolute Percentage Error) ≤ 5%. This research provides advanced predictive tools and precise model support for long-term vegetation restoration efforts.

Understanding the effect of occupational stress on sleep quality in firefighters: the modulating role of depression and burnout.

Sleep quality of firefighters can be negatively affected by occupational stressors. A cross-sectional investigation was conducted to understand how work-related stress, post-traumatic stress, burnout and depression collectively contribute to sleep quality. Professional firefighters in Northern Iran completed a survey comprised of demographic information, the Pittsburgh Sleep Quality Index, HSE's Stress Indicator Tool, the Posttraumatic Stress Disorder Checklist, Maslach's Burnout Inventory, and the Beck Depression Inventory during a work rest break. Data were analysed using structural equation modelling. Mean age of the 2339 firefighters who completed the survey was 32.30 (5.74) years. Most experienced poor sleep quality, scoring above the established cut-off of 5. Levels of work-related stress, post-traumatic stress, burnout and depression were high. Fit indices of the final theoretical model were all adequate: the obtained and adjusted goodness-of-fit indices were 0.925 and 0.917 respectively. Comparative, and incremental fit indices were 0.946 and 0.948 respectively. Root mean squared error of approximation was 0.061. Post-traumatic stress was directly and indirectly related to sleep quality through eight paths, modulated by burnout variables and depression. Work-related stress was negatively related to sleep quality through four paths modulated, by burnout variables and depression. The findings illustrate the complex relationships of work-related stress and post-traumatic stress and sleep quality. High levels of poor sleep quality in this occupation emphasise the need to develop targeted and sustainable interventions to manage occupational stressors, burnout and depression to improve sleep quality in firefighters.

Hemodynamic characteristics of pulsatile blood flow through bifurcated stenosed carotid artery

Purpose Carotid artery is often associated with plaque deposition because of its shape and associated flow features. The shape of stenosed bifurcation is characterised by bifurcation angle (ß), planarity angle (α) and severity of stenosis (b). In the present work, three-dimensional numerical computations have been performed to analyse the effect of these geometrical parameters of carotid bifurcation on the characteristics of flow. Design/methodology/approach Governing equations of this study were solved using ANSYS Fluent 20.1 and the blood flow was considered as laminar, pulsatile and non-Newtonian. Instantaneous flow behaviour has been illustrated using vorticity, velocity and helicity contours, whereas the time-averaged wall shear stress ( τw¯) and oscillatory shear index (OSI) quantify the time-averaged behaviour. Findings The recirculation zone and secondary flow are ascertained to be stronger for higher bifurcation angle as compared to the lower bifurcation angle. Strength of the secondary flow is found to reduce with increase in α from 0° to 10°, whereas it grows as α varies from 10° to 20°. For higher bifurcation angles, τw¯ is lower than 2 Pa and OSI is greater than 0.2 on the outer walls. Similar observations were made for τw¯ and OSI distribution on bottom wall in non-planar cases, which predicted atherogenic locations. Originality/value The values for ß were taken as 30°, 45°, 60° and 75°, whereas for α, range of 0°–20° was chosen. The stenosis was considered on the outer wall of internal carotid artery and its severity was considered within the range of 0%–60%.