Effects Of Stress Research Articles

Caloric Vestibular Stimulation Alleviates Cold Water Swimming Stress Induced Changes in BDNF and Haematological Parameters

Introduction: Stress is inevitable in daily life. Stress in long term has been implicated in the development of physical and neuronal disorders. Various studies have described the levels and role of BDNF in the brain following stress. Studies representing the changes in serum BDNF and wet weight of organs in stress are limited and controversial. Aim: The aim of the present study is to find the effect of stress on serum BDNF concentration, wet weight of selected organs, haematological parameters and to evaluate the effectiveness of caloric vestibular stimulation on stress-induced changes in these parameters. Methods and material: Male Wistar rats were exposed to cold water swimming stress for 14 days for a duration of 30 minutes per day. Serum corticosterone and serum BDNF were measured using the ELISA method. Weight of liver, spleen, thymus and lymph nodes were measured and their relation to body weight was calculated. Total RBC count, total WBC count, platelet count and haemoglobin concentration were analysed. Results: A statistically significant increase in serum corticosterone and BDNF was observed following stress. Liver weight, thymus weight and lymph nodes weight did not show any significant changes but spleen weight has reduced in the normal recovery group following stress. Total RBC count, total WBC count, platelet count and haemoglobin levels were significantly higher in the stress group. Caloric vestibular stimulation was effective in managing stress-induced changes in serum corticosterone, BDNF and spleen weight. Conclusion: Caloric vestibular stimulation is effective in restoring the stress-induced changes.

Anti-oxidative stress effects of ethyl acetate fraction of Diaphananthe bidens Leaf in Streptozotocin-Induced Type-2 Diabetic (T2D) Rats

Anti-oxidative stress effects of ethyl acetate fraction of Diaphananthe bidens Leaf in Streptozotocin-Induced Type-2 Diabetic (T2D) Rats

Effects of chronic heat stress on spleen structure, apoptosis and immune response in Siberian Sturgeon (Acipenser baerii)

Chronic heat stress induced by global warming has important implications for fish survival, and the response of important immune organs, such as the spleen, to chronic heat stress remains to be investigated. In this study, one control group (20 ℃) and two heat stress groups (24 ℃ and 28 ℃) were set up to investigate the effects of heat stress on the spleen of Siberian Sturgeon (Acipenser baerii). As per the histological section analysis, heat stress caused vacuolization, reticulocyte hyperplasia, and macrophage infiltration in the spleen, with hyperplasia being more pronounced in the 28 ℃ group. The flow cytometry results showed that the spleen’s apoptosis level significantly increased at 28 ℃ (p < 0.05). Hematological studies revealed a significant increase in the number of red blood cells in the 28 ℃ group (p < 0.05). Meanwhile, the mRNA expression of immune-related factors (tgf-β, il-1β, and il-8) was significantly higher in the 28 ℃ heat stress group compared with the control group. This study reveals the effects of heat stress on the A. baerii spleen and contributes to the understanding of coping strategies of cold-water fish to chronic heat stress.

Study on a Pseudo-Elastic Model for High-Damping Rubber

With advancements in seismic isolation and damping technology, high-damping rubber (HDR) bearings are now widely used. However, significant gaps remain in HDR-analysis model research, with few studies integrating multiple factors, the Mullins effect, and stiffness hardening for more accurate practical predictions. This study classifies the effective behavior of HDR and examines the stress–strain relationships of different behavioral types using more appropriate equations. Mathematical models were established based on pseudo-elasticity theory, which is an extension of continuum mechanics. Subsequently, parameter functions were developed through parameter determination tests and regression analysis, leading to the completion of the pseudo-elastic model for HDR. Finally, the model’s effectiveness was validated through validation tests. This study finds that behavior classification effectively examines phenomenological-based HDR stress–strain relationships, as distinct behavioral patterns are not adequately captured by a single approach. Incorporating tests to functionalize material parameters complements theoretical models. Additionally, accurately explaining HDR behavior requires considering the Mullins effect and stiffness hardening, influenced by the coupled effects of temperature, strain amplitude, and compressive stress. Consequently, this HDR pseudo-elastic model offers a comprehensive explanation of HDR behavior, including the Mullins effect and stiffness hardening, under various influencing factors based on clear mechanical principles and explicit computational procedures.

Environmental Pollution and Oxidative Stress: Health Effects During Pregnancy: A Review

Oxidative stress is an imbalance between reactive oxygen species production and antioxidant defense that can lead to reproductive disorders and poor pregnancy outcomes. Environmental pollution under climate change is involved in reactive oxygen species formation and may cause various dysfunctions of the reproductive system. Oxidative stress is a widespread factor that affects the physiology of the male and female reproductive systems, leading to high levels of DNA damage and infertility. Miscarriage, preeclampsia, and premature birth are all linked to oxidative stress. Environmental pollution induces excesses of oxidative stress by expanding ROS generation or overwhelming the physiological responses of the antioxidant defense system. This increases cellular damage, inflammation, and the development of numerous diseases. Here, we present a brief outline of the physiological and developmental roles that oxidative stress plays during pregnancy. We also offer some insights into the underlying mechanisms that have been put forth, which culminate in a summary of the harmful effects of oxidative stress that have an environmental origin in pregnancy-related complications. The current work may motivate the design of more focused wellbeing measures in order to prevent and promote human health and anticipate unfavorable pregnancy outcomes.

The Hope Therapy Effect Toward Depression, Anxiety, and Stress of Tuberculosis Patients with Multi-Drug Resistance at Jayapura’s Healthcare Center, Papua

Background: Indonesia is the third country with a high-rate case of tuberculosis with multi-drug resistance, for a percentage of 5% per 100.000 population. In Papua, TB-MDR becomes the main problem of health with a successful percentage of medication at 68.7%, an indicator of WHO higher than 85%. The complexity and the prolonged occurrence make the patients to have mental health illnesses, such as depression, anxiety, and stress. The field data of depression cases consisted of 65 patients. 50% with had mild depression, 20% with moderate, and 25.55 with severe. Patients with anxiety ranged from 16.7% to 37.29%. Patients with severe stress consisted of 20%. The mental illness health problems for TB-MDR patients required the roles of the nurses, such as counseling based on HOPE therapy. Purpose: Analyzed the effects of HOPE therapy to manage depression, anxiety, and stress levels. Methods: Quasi-experimental research applied a systematically assigned control group. The population consisted of patients with TB-MDR receiving medication at Jayapura's healthcare center, 40 individuals. Results: HOPE therapy effects for depression, stress, and anxiety levels applied the Wilcoxon test. The obtained result was a p-value lower than 0.05. The results indicated the effect of HOPE therapy medication on depression, stress, and anxiety levels. The intervention group had decreased depression, stress, and anxiety levels with p-values of 0.043 and 0.012. The results contradicted the control group. The obtained p-value was higher than 0.05, indicating no effect. The p-values were 0.721, 0.532, and 0.670. Conclusion: HOPE therapy was useful for TB-MDR patients with mental illness. The administered HOPE therapy for patients could improve their confidence and hopes to live better and recover.

Effect of salinity stress on the morphological parameters of <i>Hura crepitans</i> L. ameliorated with <i>Calapogonium mucunoides</i> DESV. and Biochar

Salinity is one of the most serious limiting factors for plant growth and production. This study assessed the effect of salinity stress on the morphological parameters of Hura crepitans ameliorated with Calapogonuim mucunoides Desv. and Biochar. Standard methodology was adopted to examine physicochemical properties of the soil and morphological parameters of the plant. The physicochemicalproperties of the experimental soils was significant at p=0.01. Morphological parameters of shoot length of H. crepitans at 1% non-amended saline soil for week 6 and 7 recorded 4.03±4.03cm which indicated a significant reduction (p=0.01) when compared to control 15.70±3.35 and 19.50±4.43cm respectively. The amelioration of the saline soil at 0.001% KI with biochar and C. mucunoides (21.80±0.05 and 22.43±3.52cm) of H. crepitans shoot length was significant when compared to the control 21.00±4.00cm. The higher the concentration of salinity, the lower the petiole length of H. crepitans for amended treatments. The photosynthetic pigment 56.70±2.47 of H .crepitans at 0.001% was significant (p=0.05) when compared to the control 51.36±2.99.This results showed that salinity causes a detrimental effect on some plant growth parameters. However, amelioration of saline soil with C. mucunoides and biochar recorded a satisfactory remediation effect on the growth of H. crepitans. Based on this research, amelioration treatment such as C. mucunoides and biochar can be use to improve crops planted in saline soil.

Deciphering Acclimation to Sublethal Combined and Sequential Abiotic Stresses in Arabidopsis thaliana.

Plants are frequently exposed to environmental challenges. Responses to sub-lethal abiotic stress combinations are complex and often distinct from responses to individual stresses and remain poorly understood. Investigating traits and molecular factors mediating acclimation to stress combinations is essential for the development of climate change-resilient field crops. Here, we studied the morphological, physiological, and molecular responses of Arabidopsis thaliana to i) co-occurring high temperature and drought and ii) flooding followed by drought, both of which have increased in frequency due to climate change, and the individual component stresses: high temperature, drought and flooding. A set of 15 physiological and morphological traits were assessed during single and combined stresses. By combining these comprehensive trait analyses with transcriptome characterization, we established the generally additive negative effects of simultaneous or sequential stresses on plant morphology and physiology compared to the corresponding individual stresses. Although drought had a mild effect on various growth, morphological and physiological traits in both stress combinations, a unique transcriptome signature emerged upon combination with high temperature simultaneously or flooding sequentially. Molecular processes identified as important for multi-stress resilience included plastid-nucleus communication, ABA signaling and photo-acclimation. Based on the RNA-seq data, a set of 39 genes was identified as potential multi-stress response regulators. Mutants were tested to validate the contribution of these genes to plant survival and phenotypic acclimation under combined stress. We confirmed the involvement of several genes in regulating phenotypic acclimation traits. Among the identified factors were EARLY FLOWERING 6 (ELF6) and ARABIDOPSIS TÓXICOS EN LEVADURA 80 (ATL80), with substantial effects on plant growth, leaf development and plant survival (wilting) during high-temperature drought and post-submergence drought, respectively.

Environmental Stress Drives Transgenerational Epigenetic Inheritance through miR-212/132 Expression Alterations

Transgenerational Epigenetic Inheritance (TEI) is a phenomenon that is deeply affected by the presence of environmental stress and disease. This phenomenon has been proposed to accelerate the evolution of many animal species. However, most current studies commonly focus on the C. elegantly which is frequently presented as deviating a lot from humans and the studies on mice still fail to propose a plausible explanation for the detailed mechanism of TEI in mammals. In this study, we primarily focused on the effect of environmental stress on mice and the possible TEI characteristics it may perform. The miR212/132 was chosen as the main target for studying and the role it play in the TEI is verified. The hippocampus-sperm communication mechanism of miR212/132 will also be focused and verified which revealed why the differential expression happen in the germ-line cell.

Welfare and performance benefits of shade provision during summer for feedlot cattle in a temperate climatic zone.

There is increasing interest from cattle lot-feeders in the use of shade to mitigate the effects of a potential heat stress event, though it is unclear whether the reported benefits of shade in previous studies conducted in more high-risk heat stress zones are pertinent in cooler temperate zones. The objectives of this study were to measure the welfare and performance benefits of shade provision for lot-fed cattle at a commercial feedlot located in a mild heat-stress risk zone in Western Australia. Six blocks of black Angus (Bos taurus) steers were inducted into the feedlot over six time-windows across a southern hemisphere summer, with 80 cattle per block housed in a partially shaded pen (providing 3.125 m2 of shade per animal) and 80 in an unshaded pen. Parameters assessed in 960 cattle over the first 70 days in the feedlot included weight gain, feed intake, and physiological and behavioral indices of overall health and welfare. Over the months of October through to May in which the experiment was conducted, shaded cattle demonstrated a modest 0.13kg overall increase in average daily gain across the 70-day feedlot period (P = 0.13). There was no difference in dry matter intake between any block or treatment. The physiological and behavioral markers of health and welfare revealed that, even during to hottest times of the experiment, the cattle were quite able to thermoregulate, via increased panting and seeking shade (if available), to maintain physiological homeostasis. In addition, we measured the effect of heat stress and shade provision on the affective state of the cattle. Qualitative behavioral assessment was used to indicate that the cattle in the 'no stress' temperature humidity index (THI) category and the shaded cattle in the 'moderate stress' THI category displayed the most positive demeanor (P < 0.05), being described as more 'settled and sociable', while the unshaded cattle in the 'moderate stress' THI category and all cattle in the 'severe stress' THI category were described as more 'agitated/anxious' (P < 0.05). Overall, the findings from the present study suggest that there are definite welfare and modest performance benefits associated with providing cattle with shade in summer in a feedlot situated in a temperate climatic zone.

Investigating the effect of chronic stress, depressive-like pathology and cognitive impairments on acute myocardial infarction: sex-differentiated effects

Abstract Background/Introduction Depression is an independent risk factor for cardiovascular disease (CVD) with the prevalence rates being higher in women than men in the general population and among patients with CVD. Furthermore, an association between myocardial infarction and cognitive deficits has been proposed, but the pathophysiological mechanisms that are responsible for the brain-heart axis interaction have not been elucidated. Purpose The present study aims to: 1) evaluate sex differences in the effect of chronic unpredictable stress (CUS) on myocardial infarct size (IS) and 2) determine the molecular pathways affected by CUS in the heart. Methods Adult male and female C57BL/6J mice, were randomly divided into 4 groups (n=7/group): CON (Control, sham surgery), iCON (Control, myocardial ischemia/reperfusion (IR)), STR (Stress, sham surgery) and iSTR (Stress, IR). Mice were intermittently exposed to the CUS protocol consisted of 4 different stressors for 6 consecutive weeks. Locomotor activity (open field-OF), anxiety-like alterations (OF, elevated plus-maze-EPM test), depressive-like pathology (tail suspension test- TST) and cognition (Y-maze and Novel Object Recognition-NOR tests) were evaluated. After behavioral evaluation, the animals were subjected to 30 min I followed by 24 h of R or sham surgery and infarct size (IS) was determined via double Evan’s Blue and triphenyltetrazolium chloride staining. In a second series of experiments (n=5/group), the ischemic part of the myocardium was collected at 24h R and subjected to label free proteomic analysis, in order to identify alterations associated with the effect of CUS and IR. Results CUS induced anxiety, depressive-like pathology and cognitive deficits as indicated by the increased time spent in the closed arms of the EPM (p&amp;lt;0.005), the increased immobility time (TST, p&amp;lt;0.05), the reduced preference for the novel object (NOR, p&amp;lt;0.05), and the significant body weight reduction (p&amp;lt;0.001), in both male and female mice. CUS significantly increased IS (p&amp;lt;0.001) in both male and female mice. Proteomic analysis revealed that CUS affected the heart proteome, related to endoplasmic reticulum stress, mitochondrial damage and apoptosis, of both sexes in the absence of IR. Female mice were more susceptible to IR damage in absence of CUS with 248 significant genes (FDR&amp;lt;0.05) being deregulated mainly belonging to Keap-Nrf2-ARE signaling pathway, in contrast to 168 significant genes in male mice. In male mice, CUS exacerbated the IR injury proteome changes mainly related to induction of apoptosis and mitochondrial dysregulation (292 significant genes, FDR&amp;lt;0.05 for males vs 102 for females). Conclusions Chronic exposure to stress increases depressive-like pathology and cognitive deficits, leading to heart proteome alterations and increased IS in both sexes. Sex differences were observed indicating that the coexistence of CUS and IR render the male heart more susceptible to myocardial damage.

Beat-to-beat analysis of hemodynamic response to mental and psychological stress in sickle cell anemia

Abstract Vaso-occlusive crises are a hallmark symptom of sickle cell disease. Physical stressors can trigger decreased microvascular blood flow and increase the risk for vaso-occlusive crises. However, the effect of mental and psychological stressors on vascular physiology in sickle cell disease is not well-established. We hereby examined fluctuations in continuous blood pressure to evaluate hemodynamic changes in sickle cell disease patients during mental and psychological stress. Thirteen sickle cell disease subjects from the Children’s Hospital Los Angeles and 11 healthy volunteers were recruited. Continuous blood pressure was recorded during two mental tasks and one psychological stress task. Systolic beat-to-beat blood pressure variability measurements were calculated for each subject. Three very short-term blood pressure variability metrics served as outcome measures: standard deviation, coefficient of variation, and average real variability. Peripheral augmentation index was calculated from arterial waveforms. Linear mixed effects models evaluated associations between patient factors and outcome measures. Sickle cell disease patients exhibit increased systolic blood pressure variability in response to psychological stress. All subjects exhibited a decrease in systolic blood pressure variability in response to mental stress tasks. During mental stress, both groups displayed increased augmentation index, reflective of stress-induced vasoconstriction, while psychological stress in sickle cell disease patients led to both decreased mean arterial pressure and increased augementation index, suggestive of uncompensated vasoconstriction. These findings emphasize the impact of mental and psychological stressors on vascular function in sickle cell disease and the potential for monitoring physiological signals to predict vaso-occlusive crisis events.

The Effect of Workload and Organizational Climate on Turnover Intentions with Job Stress as an Intervening Variable in Generation Z Employees of PT. MMI Ambon Regional

The purpose of this research is examining effect of workload on work stress, examining effect of workload on turnover intention, examining effect of workload on turnover intention through work stress, examining effect of organizational climate on workload, examining effect of organizational climate on turnover intention, examining effect of organizational climate on turnover intention through work stress, and examining effect of work stress on turnover intention among Generation Z employees of PT. MMI (affiliated with PNM) in the Ambon region. This research employs a quantitative approach by distributing questionnaires to 213 employees, assisted by data processing using SmartPLS. The results indicate that workload positively influences work stress, workload positively influences turnover intention, workload positively affects turnover intention through work stress, organizational climate negatively impacts work stress, organizational climate don’t have significant effect to turnover intention, organizational climate negatively influences turnover intention through work stress, and work stress significantly influences turnover intention

Effects of Abscisic Acid on the Physiological and Biochemical Responses of Saccharina japonica Under High-Temperature Stress

Saccharina japonica is one of the most productive aquatic plants in the world, widely used in food, feed, medicine, and other industries. Predominantly inhabiting temperate marine environments in mid- to high-latitude regions of the Northern Hemisphere, the growth of S. japonica is significantly limited by high-temperature stress. Abscisic acid (ABA) plays an important role in plant growth and development and stress responses. However, the role of ABA on high-temperature stress tolerance in S. japonica still needs to be further elucidated. Here, we found that exogenous ABA significantly alleviated disease and decay in S. japonica under high-temperature stress while also increasing the relative growth rate, chlorophyll fluorescence parameters, photosynthetic pigment, and osmotic substance content. Meanwhile, exogenous ABA enhanced the activity of protective enzymes and up-regulated the transcript levels of antioxidant-related genes, thereby reducing oxidative damage. Most importantly, we observed a significant increase in ABA content and the transcript levels of key genes involved in ABA synthesis in S. japonica under high-temperature stress, which were further amplified by the addition of exogenous ABA. In conclusion, this study provides evidence that ABA can moderate the detrimental effects of high-temperature stress and provides a theoretical basis for the screening of S. japonica germplasm resources and the cultivation of new stress-resistant varieties.

Investigating N6-methyladenosin RNA modification as a mediator of microRNA mechanical regulation in the heart

Abstract Background The heart is exposed to mechanical forces and continuously adapts to its environment in a process known as cardiac remodeling. Excessive mechanical load is a primary driver of pathological cardiac remodeling, leading to heart failure (HF), a prominent cause of morbidity and mortality worldwide. A set of microRNAs (miRs), termed mechano-miRs, has been identified to respond to mechanical forces and contribute to heart pathophysiology and HF. N6-methyladenosine (m6A) RNA modification is emerging as a novel regulatory layer impacting gene expression and occurring both in coding and non-coding RNAs. In this context, the N6-adenosine-methyltransferase METTL-3 regulates the processing of miR primary transcripts (pri-miRs) to functional miRs, promoting angiogenesis and cardiac repair after myocardial infarction. On the other side, dysregulation of m6A due to a defect in FTO, a m6A demethylase, has been implicated in HF. However, the role of m6A RNA modifications in heart mechanical responses and mechano-miR regulation remains unexplored. Purpose This project aims to: 1) investigate the impact of mechanical overload on the expression of m6A regulatory machinery components; 2) unveil the role of m6A-mechano-miRs axis in mechanically induced responses driving pathological cardiac remodeling leading to heart failure. Methods and Results Using living myocardial slices (LMS) technology, we modulate mechanical load in a multicellular environment while maintaining physiological behavior. Human LMS, obtained from the left ventricle of human donor non-failing hearts (NHS Blood and Transplant INOAR program, IRAS project ID: 189069) and rat LMS are subjected to two degrees of mechanical preload: physiological sarcomere length (SL) (SL = 2.2 μm) and overload (SL = 2.4 μm). This enables us to mimic the effects of mechanical stress on the heart during HF (volume overload model). LMS are maintained for 48 hours under electrical stimulation in circulating oxygenated media at 37°C. Mechanically overloaded LMS exhibit decreased contractility, accompanied by an increase in global m6A levels compared to physiological controls. Consistent with this finding, the analysis of the expression of m6A machinery reveals a downregulation of m6A demethylases (FTO and ALKBH5) in overloaded LMS. We identified putative cardiac mechano-miRs by small-RNA sequencing in both human and rat LMS and next predicted potential m6A sites on their primary transcripts via SRAMP (sequence-based RNA adenosine methylation site predictor). Conclusions Mechanical overload affects global m6A levels and the expression of m6A demethylases in the heart. Ongoing analysis of the m6A profile on the identified mechano-miR primary transcripts and mRNA targets holds promise for unveiling novel mechanically regulated m6A events, providing insights for transformative therapeutic strategies.

Social Support Management and Academic Stress: Implications for Students' Subjective Well-being

The high dropout rate suggests that students' well-being is in doubt, especially in relation to their subjective well-being. This study aims to investigate the impact of perceived social support and academic stress on subjective well-being. This research method uses a quantitative approach. The subjects of this study were 83 students of Faculty Pharmacy X University who were selected by simple random sampling technique. The data collection method used was the subjective well-being scale, social support, and academic stress. The data analysis technique used was multiple linear regression. The results showed that: (1) there is an influence of social support and academic stress on subjective well-being with the value of F count = 9.367 &gt; F table = 3.11 and p value = 0.000 and has an influence contribution (R2) of 18.6%; (2) there is no significant influence of social support on subjective well-being with a beta coefficient value (β) = 0. 141, t count = 1.284 &lt; t table = 1.989, and p value 0.202 (p &gt; 0.05); (3) there is a positive and significant effect of academic stress on subjective well-being with a beta coefficient value (β) = 0.353, t count = 3.202 &gt; t table = 1.989, and p value 0.002 (p &lt; 0.05). The conclusion in this study is that there is a significant influence between social support and academic stress on students' subjective well-being.

Plant growth regulators improve the yield of white lupin (Lupinus albus) by enhancing the plant morpho-physiological functions and photosynthesis under salt stress

BackgroundWhite lupin (Lupinus albus L.) is a multi-purpose, climate resilient, pulse crop with exceptionally high protein content that makes it a suitable alternative of soybean in livestock feed. Although white lupin grows well on marginal sandy soils, previous studies have reported its sensitivity towards salinity stress. This experiment aims to assess the influence of salinity stress and mitigating role of plant growth regulators (PGRs) on performance of white lupin.MethodologyThe white lupin plants were sown in pots maintained at three salinity levels (1, 3 and 4.5 dS m− 1) throughout the growing season and foliar sprayed with different PGRs, including ascorbic acid, potassium chloride, boric acid, ammonium molybdate and methionine at sowing, four weeks after emergence and at the initiation of flowering. Foliar spray of distilled water and salinity level of 1 dS m− 1 were maintained as control treatments. Data were recorded for seed germination indices, plant growth, antioxidant enzymes and photosynthetic efficiency variables.ResultsThe severe salinity stress (4.5 dS m− 1) reduced the germination indices by 9–50%, plant growth traits by 26–54%, root nodulation by 12–26%, grain development by 44–53%, antioxidant enzymes activity by 13–153% and photosynthetic attributes by 1–8% compared to control (1 dS m− 1). Different PGRs improved several morpho-physiological attributes in a varied manner. The application of potassium chloride improved seed vigour index by 53%, while ascorbic acid improved root nodulation by 12% and number of pods per cluster by 75% at the severe salinity level. The foliar application of PGRs also displayed a recovery of 140% in the activity of superoxide dismutase and 70% in catalase. The application of multi zinc displayed an improvement of 37% in plant relative chlorophyll, while ascorbic acid brought an increase of 25% in non-photochemical quenching and 21% in photochemical quenching coefficient at the severe salinity level. On contrary, the application of PGRs brought a relatively modest improvement (8–13%) in quantum yield of photosystem II at slight to moderate (3 dS m− 1) salinity stress. The correlation analysis confirmed a partial contribution of leaf area and seed vigour index to overall photosynthetic efficiency of white lupin.ConclusionsClearly, salinity exerted a negative impact on white lupin through a decline in chlorophyll content, activity of antioxidant enzymes and efficiency of photosynthetic apparatus. However, PGRs, especially ascorbic acid and potassium chloride considerably improved white lupin growth and development by mitigating the negative effects of salinity stress.

Effect of Support-Induced Stress on the Failure Characteristics of Deep Tunnels Based on True-Triaxial Compression Tests

Effect of Support-Induced Stress on the Failure Characteristics of Deep Tunnels Based on True-Triaxial Compression Tests

Rumen fermentation shifts and microbial dynamics in mid-lactating holstein dairy cows experiencing heat stress and subsequent recovery periods.

In this study, we investigated the effects of heat stress (HS) on rumen fermentation, blood parameters, and ruminal microbial communities in mid-lactating Holstein dairy cows in Korea. Our study involved 12 mid-lactation Holstein dairy cows aged 55.54 months with 2.5 ± 0.65 parities and 100 to 200 days in milking (DIM), fed a total mixed ratio (TMR) diet. Samples were collected during HS (temperature-humidity index (THI) = 81.69) and recovery (RC) period (THI 69.84). The samples were analyzed for rumen fermentation, blood parameters, heat shock proteins, and microbial communities in dairy cows. The milk yield, milk fat, milk protein, and milk urea nitrogen (MUN) levels differed significantly between two -time points (p < 0.05). Rumen pH and volatile fatty acid (VFA) concentrations, the pH was not significantly different (p=0.619) between HS and RC periods; however, the ammonia nitrogen (NH3-N) levels increased during HS period ), however, there was no significant difference (p>0.05). Blood total protein significantly increased during HS period compared with that during RC period (p < 0.05), while no significant differences were observed in other parameters between the two periods. HSP27, HSP70, and HSP90 increased in dairy cows under HS conditions compared with those during the RC period. Taxonomic classification revealed that Firmicutes and Bacteroidetes dominated the bacterial community. PERMANOVA and PERMDISP showed significant differences in rumen bacterial diversity between HS and RC periods, based on Unifrac metrics (p=0.044 and p=0.015, respectively), indicating taxonomic variations. Microbial networks with correlations of > 0.8 (p < 0.05) showed a complex structure with equal positive and negative connections, indicating Anaerohabdus furcosa and Ruminiclostridium cellobioparum as key species during the HS and RC periods respectively. Heat stress significantly impacts Holstein dairy cows' physiological and metabolic processes, altering rumen fermentation, blood biochemistry, and gut microbiota during mid-lactation.

Antioxidant Capacity of Thyme (Thymus vulgaris) Essential Oil and Its Effect on In Vivo Fertility of Rams Subjected to Testicle Heat Stress.

The detrimental effects of hyperthermia on the testes and the protective effect of thyme essential oil against testicular damage induced by this stress in rams were studied. Twenty-four rams of the Barbarine breed with an average weight of 62.5 ± 0.3 kg and an average age of 24 ± 0.6 months. The experiment consisted of inducing localized heat stress on the first group of rams by applying heat bags to both testicles of six rams (G s). The second group underwent the same heat stress on the testes but received orally 100 µL/day/animal of thyme essential oil (G s-he). A positive control did not undergo stress but received thyme essential oil (G he) with the same doses as the (G s-he) group, and the negative control did not undergo either stress or receive the essential oil of thyme (G c). One hundred twenty-eight adult ewes of the same breed divided into four groups of 32 ewes were used to study the effect of different treatments on the in vivo ram's fertility. Ewes are synchronized and we have applied natural mating with oestrus control, the reproduction balance sheet is calculated after lambing. The results showed that tests of heat stress (HS) negatively affect semen quality but did not cause infertility. However, neither tests for heat stress nor treatment with thyme EO significantly affected the haematological profile. The study of the effect of heat stress on the testes on fertility in vivo showed a drop in the number of females who were fertilized at the first oestrus and consequently a drop in fertility. However, the rams that suffered the same stress but were treated with EO thymus recorded an improvement in these parameters.