Stress Levels Research Articles

Hydroponic Screening at Early Seedling Stage Identified Sources of Salinity Tolerance in Wheat (Triticum aestivum L.) Crop

Wheat is a vital crop globally, essential for agriculture, economics, and food security. However, in arid and semi-arid conditions, wheat production faces significant challenges due to low water availability, uneven rainfall distribution, and high soil salinity. The germination and early seedling stages are particularly vulnerable to these stresses. Therefore, this study assessed 15 wheat genotypes for their tolerance to salinity stress during early growth stages, using a hydroponic system with four salt stress levels (0, 50, 100, and 150 mM NaCl). Significant differences were observed for genotype and salinity main effects and their interaction on all investigated traits, indicating considerable variability in the response to salt stress among the investigated wheat cultivars. High NaCl concentrations led to substantial reductions in measured parameters across genotypes, with some showing resilience while others exhibited heightened sensitivity. Stress tolerance indices, such as mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM), stress tolerance index (STI) and yield index (YI), were identified as reliable indicators for selecting salt-tolerant wheat cultivars. Consequently, Sidi Okba (G11), Ziad (G12), Tamezghida (G13) and Zidane (G14) emerged as the most promising, displaying acceptable performance under both non-stress and salt-stress conditions. These genotypes could serve as valuable genetic resources for breeding programs aimed at enhancing wheat’s salinity tolerance, particularly in arid and semi-arid regions.

How Dietary Choices and Nutritional Knowledge Relate to Eating Disorders and Body Esteem of Medical Students? A Single-Center Cross-Sectional Study

Eating disorders and body image concerns are increasingly prevalent issues among young individuals, with medical students being particularly vulnerable due to heightened stress levels. This study enrolled 879 medical students to investigate these concerns. The KomPAN questionnaire was utilized to assess dietary habits and knowledge, the Body Esteem Scale (BES) to evaluate body satisfaction, and The Eating Attitudes Test (EAT-26) to identify eating disorders. A higher level of nutritional knowledge was found to be statistically significantly associated with attempts at excessive calorie restriction among women (β = 0.0864) and negatively among men (β = −0.2039). Moreover, it was negatively associated with self-control of food intake only among men (β = −0.2060). Furthermore, a higher BMI was associated with attempts of excessive calorie restriction in both women and men (β = 0.1052 and β = 0.1656, respectively) and negatively with self-control of food intake (β = −0.0813 and β = −0.1453, respectively). A higher BMI was associated with poorer body esteem across all variables in both genders, except for upper body strength among men. Nutritional knowledge did not correspond with any of these variables, while dietary quality was positively associated with physical condition in women and with physical condition, physical attractiveness, and upper body strength in men. Our study findings suggest that dietary interventions could be improved by considering gender-based behavioral differences and focusing on portion control for individuals with a higher BMI. Caution is warranted in extrapolating the results to the general population due to the specific nature of the study population.

Nutrient-coated urea mitigates deleterious impacts of salinity and supports wheat performance by enhancing antioxidant activities, photosynthetic performance and nitrogen use efficiency

Soil salinization has increased over recent years and is negatively affecting crop productivity. Nutrient application is an effective strategy to improve abiotic stress tolerance in crops. The application of coated fertilizers has emerged as an excellent approach to mitigate the adverse impacts of soil salinity. Therefore, the present study was conducted to determine the effects of zinc and sulfur coated urea on the performance of wheat growing under saline conditions. The study comprised of diverse salinity stress levels; 0, 6 and 12 dS m-1, cross combined with normal urea (NU), zinc coated urea (ZCU) and sulfur coated urea (SCU). Salinity stress reduced wheat yield by impairing leaf water status, reducing photosynthetic pigments, osmolytes accumulation, potassium (K) and nitrogen (N) uptake while increasing sodium (Na) and chloride (Cl) uptake and hydrogen peroxide (H2O2), malondialdehyde (MDA) and electrolyte leakage (EL) accumulation. The application of ZCU increased the wheat yield by enhancing photosynthetic pigments, leaf water status, antioxidant activities, osmolytes accumulation, and reducing H2O2, MDA and EL accumulation. Furthermore, the significant increase in growth and yield of wheat with ZCU and SCU was also linked with improved K and N uptake, higher nitrogen use efficiency (NUE) and reduced Na and Cl concentration. Thus, the application of ZCU could be an effective approach to improve wheat productivity under saline conditions.

STRESS AND HEALTH BEHAVIOR OF HEALTH PROFESSIONS STUDENTS IN BULGARIA

The purpose of this study is to determine the prevalence of stress among students of various health specialties in Bulgaria and to examine its relationship with the individual and institutional characteristics of the students and with their health behavior. Methods: A survey was conducted among students from all 26 Bachelor and Master of health sciences programmes at a Medical University in Bulgaria. Information on self-assessed levels of health and stress, aspects of the health behavior (physical activity, smoking, alcohol intake, diet and sleep duration), personal (age, gender) and institutional factors (specialty and year of study) was collected with a structured questionnaire. Multinomial logistic regression was performed to evaluate the determinants of the perceived high level of stress. Results: A total of 570 (10% sample) of all students from the university with a mean age of 24 (SD 7.6) years took part in the study. The majority of students (61.7%) experienced a moderate level of stress. Self-reported high level of stress (25.4%) was significantly independently associated with three factors - female gender (OR=2.92, 95% CI=1.09-7.81), low level of self-rated health (OR=6.95, 95% CI=2.17-22.25) and higher (fourth or fifth) year of study compared to first (OR=5.49, 95% CI=1.72-17.59; OR=4.06, 95% CI=1.36-12.16). Conclusions: Stress is an important problem affecting the health of this group of the population. Active actions for building environments conducive to and supporting students' mental health are necessary, for which medical universities are in a very favourable position.

Shedding light on the shadows: oxidative stress and its pivotal role in prostate cancer progression

ObjectivesData on oxidative protein damage, total antioxidant capacity (TAC) and lipid peroxidation in progression of prostate cancer remain elusive. So far, the influence of the presence of perineural invasion on the level of oxidative stress has not been described. Additionally, there is limited data on the level of oxidative stress in patients’ urine.MethodsWe compared the levels of oxidative stress markers in serum and urine in 50 patients with prostate cancer depending on the tumor stage and histological grade, the Gleason score, and the presence of perineural invasion.ResultsWe found a significantly de-creased level of serum thiol groups and TAC in participants with prostate cancer. Similarly, serum Amadori products and malondialdehyde (MDA) were higher in patients than in healthy men. There was a significantly decrease in TAC and a significantly increased MDA in the urine of prostate cancer patients. As the stage of cancer increased, a decrease in the thiol group concentration and TAC as well as an increase in the concentration of lipid peroxidation products in the serum was observed. The serum level of advanced oxidation protein products (AOPP) increased in the group with Gleason scores greater than 7. Furthermore, serum thiol groups and TAC were reduced in the group with Gleason >7 as compared to Gleason <7. The presence of perineural invasion significantly reduced serum and urinary TAC and increased urinary AOPP concentration.ConclusionsThese results indicate a significant role for oxidative damage in prostate carcinogenesis and its progression. Characterizing oxidative and nitrosative damage to proteins may be useful in designing targeted therapies for prostate cancer patients.

The psychological implications of COVID-19 over the eighteen-month time span following the virus breakout in Italy

BackgroundIn a short time, the COVID-19 pandemic has exerted a huge impact on many aspects of people’s lives with a number of consequences, an increase in the risks of psychological diseases being one of them. The aim of this experimental study, based on an eighteen-month follow-up survey, is to assess the psychological effects of the COVID-19 pandemic, in particular, changes in stress, anxiety and depression levels, and the risks of developing Post-Traumatic Stress Disorder (PTSD).MethodsA follow-up survey was performed on a sample of 184 Italian individuals to collect relevant information about the psychological impact of COVID-19. Predictors of the components of the psychological impact were calculated based on the ANCOVA model.ResultsThe analysis of the online questionnaires led to the conclusion that a high percentage of the participants suffer from levels of stress, anxiety and depression higher than normal as well as an increased risk of PTSD. The severity of such disorders significantly depends on gender, the loss of family members or acquaintances due to the pandemic, the amount of time spent searching for COVID-19 related information, the type of information sources and, in part, on the level of education and income. The time factor had a more severe effect on the low-income population.ConclusionCOVID-19 has entailed a very strong psychological impact on the Italian population also depending on the coping strategies adopted, the level of mindful awareness, socio-demographic variables, people’s habits and the way individuals use the available means of communication and information.

Pebble to the Metal: A Boulder Approach to Enrichment for Danio rerio.

Zebrafish are an established and widely used animal model, yet there is limited understanding of their welfare needs. Despite an increasing number of studies on zebrafish enrichment, in-tank environmental enrichment remains unpopular among researchers. This is due to perceived concerns over health/hygiene when it comes to introducing enrichment into the tank, although actual evidence for this is sparse. To accommodate this belief, regardless of veracity, we tested the potential benefits of enrichments presented outside the tank. Thus, we investigated the preferences and physiological stress of zebrafish with pictures of pebbles placed underneath the tank. We hypothesized that zebrafish would show a preference for enriched environments and have lower stress levels than barren housed zebrafish. In our first experiment, we housed zebrafish in a standard rack system and recorded their preference for visual access to a pebble picture, with two positive controls: visual access to conspecifics, and group housing. Using a crossover repeated-measures factorial design, we tested if the preference for visual access to pebbles was as strong as the preference for social contact. Zebrafish showed a strong preference for visual access to pebbles, equivalent to that for conspecifics. Then, in a second experiment, tank water cortisol was measured to assess chronic stress levels of zebrafish housed with or without a pebble picture under their tank, with group housing as a positive control. Cortisol levels were significantly reduced in zebrafish housed with pebble pictures, as were cortisol levels in group housed zebrafish. In fact, single housed zebrafish with pebble pictures showed the same cortisol levels as group housed zebrafish without pebble pictures. Thus, the use of an under-tank pebble picture was as beneficial as being group housed, effectively compensating for the stress of single housing. Pebble picture enrichment had an additive effect with group housing, where group housed zebrafish with pebble pictures had the lowest cortisol levels of any treatment group.

Stress perception, coping behaviors and work-privacy conflict of student midwives in times of COVID-19 pandemic: the “Healthy MidStudents” study in Germany

BackgroundStudent midwives deliver care for women under challenging job demands, which may affect their mental health– thus creating a high need for health promotion. Given the lack of research addressing this topic, the aim of this study is to examine the links between stress perception, coping behaviors, work-privacy conflict, and perception of COVID-19 pandemic impact on studies of student midwives in northern Germany.MethodsData were collected using a cross-sectional online-survey at nine midwifery study sites in northern Germany from October 2022 to January 2023. 342 student midwives (response rate: 61.3%) were surveyed on stress perception, coping behaviors, work-privacy conflict, and perceived impact of the COVID-19 pandemic on their studies. Descriptive, linear regression and moderation analyses were run to test explorative assumptions.ResultsResults revealed that higher levels of perceived stress were reported by 13.4% of student midwives. Social support (M = 13.76, SD = 2.19) and active stress coping (M = 10.72, SD = 2.01) were identified as most prevalent coping behaviors in the present sample. It was found that work-privacy conflict was positively associated with stress perception (ß = 0.53, p =.001) and maladaptive coping behaviors (alcohol and cigarette consumption: ß = 0.14, p =.015), and negatively associated with adaptive coping behaviors (positive thinking: ß = − 0.25, p =.001, social support: ß = − 0.23, p =.001). Students with children reported significantly lower levels of social support than students without children. 55.6% of student midwives perceived a negative impact of the COVID-19 pandemic on their studies (mostly on lectures, seminars, and contact with fellow students).ConclusionsKey findings highlighted moderate stress levels among student midwives during theoretical study stage. Based on current research, prevalence of high stress levels among student midwives remains unclear. Given the overall heterogeneous, limited research on student midwives’ stress perception, coping behaviors, work-privacy conflict and perceptions of COVID-19 pandemic impact on studies, implications for research are suggested, e.g. longitudinal studies at different time points and settings and interventional studies. Findings provide a starting point for implementation of workplace health promotion in theoretical and practical stages of midwifery science study programs, e.g. training courses on stress prevention and adaptive coping, and for improvement of working conditions.

Disaggregating National Statistical Data to Assess the Sub-National SDG 6.4.2 Water Stress Indicator by Integrating Satellite Observations and Model Data

Ensuring the sustainable management of water and sanitation for all is the primary goal of Sustainable Development Goal 6 (SDG 6). SDG indicator 6.4.2 (level of water stress) is critical for monitoring the progress toward SDG 6. The assessment of the SDG indicator 6.4.2 is currently based on statistical data at the national scale, i.e., one value for one country, which cannot reflect spatial variability in water stress in a country. The lack of data at sub-national scales limits the assessment of water stress in sub-national regions. This study developed a method of disaggregating national statistical renewable water resources (TRWR) and freshwater withdrawals (TFWW) to estimate the SDG 6.4.2 water stress indicator at a sub-national scale by combining satellite remote sensing data and model simulated data. Remote sensing (RS)-based precipitation (P); the difference between precipitation and evapotranspiration (P-ET); and the difference between precipitation, evapotranspiration, terrestrial water storage change (P-ET-dS), and model-simulated naturized runoff and withdrawal water use were used as spatial and temporal surrogates to disaggregate the national-scale statistics of TRWR and TFWW to the grid scale. Gridded TRWR and TFWW can be used to calculate the water stress of any interest regions. Disaggregated TRWR, TFWW, and water stress estimation were validated at three different spatial scales, from major river basins and provinces to prefectures in China, by comparing the corresponding statistical data. The results show that the disaggregation for TRWR is generally better than for TFWW, and the overall accuracy for water stress estimation can reach up to 91%. The temporal evolution of disaggregated variables also showed good consistency with statistical time series data. The RS-based P-ET and P-ET-dS have great potential for disaggregating TRWR at different spatiotemporal scales, with no obvious differences with the results using the model simulation as a surrogate for the disaggregation of SDG indicator 6.4.2. The disaggregation accuracy can be further improved when the sub-regional statistical data of TRWR and TFWW are applied to the disaggregation approach.

STUDY OF PHYSIOLOGICAL AND BIOCHEMICAL VARIATIONS IN POPULATION GROUPS UNDERGOING ACUTE OR CHRONIC STRESS

Objective: Stress arises from derangements of personal and professional activities. The basic reason is changes in lifestyle and psychosocial adaptations. Life becomes demanding, complicated, mechanical, and devoid of health. In today’s modern world, occupational stress has become the major factor for loss of health and peacefulness of mind. Methods: This is an observational descriptive study which was conducted in a group of 84 people between 25 and 60 years of age to study the association of acute stress on salivary amylase level and effect of chronic stress on lipid profile, glycosylated hemoglobin and certain inflammatory markers in people representing different forms of stress. Three groups of the population were studied. Group 1 (n=20) - Patients undergoing any elective surgery (abdominal/genitourinary) or an invasive diagnostic procedure (upper GI endoscopy, lymph node biopsy) Group 2 (n=32) – High/middle socio-economic male or female working for ≥8 h/day with or without stress. Group 3 (n=32) – Low socioeconomic male or female earning <100 Rs/day with or without stress. Salivary alpha-amylase and chromogranin A (CgA) levels are good markers of stress. Results: There was increased levels of cortisol (p<0.0001), alpha amylase (p<0.01), and decreased levels of CgA (p<0.001) pre-procedure period as a marker of acute stress. In the chronic stress group of low income as well as high-income status, glycosylated hemoglobin, and blood lipid profile in both males and females were significantly deranged. Plasma malondialdehyde (MDA) levels and interleukin (IL)-1 and IL-2 were significantly raised in both groups. Serum ferritin level was low in the low socioeconomic group but normal in the high socioeconomic group. Conclusion: Salivary amylase level was raised in acute stress and there is a direct correlation of chronic stress with high low-density lipoprotein/ high-density lipoprotein ratio, raised glycosylated Hemoglobin, serum MDA, IL-1, 2 levels irrespective of economic group.

Essential Oil of Psidium glaziovianum Kiaersk Alleviates the Effects of Complete Freund’s Adjuvant (CFA)-Induced Arthritis by Regulating Inflammation and Oxidative Stress

Rheumatoid arthritis (RA) is a chronic and debilitating condition that affects a significant number of individuals worldwide. Unfortunately, the currently available therapeutic approaches often yield unsatisfactory results and may be accompanied by harmful side effects. A medicinal plant called Psidium glaziovianum Kiaersk has potential benefits in the treatment of this condition due to its anti-inflammatory and analgesic properties. In this study, our objective was to investigate the potential therapeutic effects of P. glaziovianum essential oil (PgEO) in alleviating arthritis symptoms in mice induced by Complete Freund’s Adjuvant (CFA). The effect of P. glaziovianum essential oil was evaluated in mice with Complete Freund’s Adjuvant (CFA)-induced arthritis. Edema sizes, macroscopic and radiographic images, cytokine levels, and oxidative stress were evaluated. Administration of PgEO at dosages of 50 and 100 mg/kg effectively prevented CFA-induced osteoarticular changes in arthritic mice, resulting in a significant reduction in joint damage. Additionally, the PgEO treatment exhibited the ability to minimize edema, a common symptom associated with arthritis. Furthermore, PgEO can modulate the levels of pro-inflammatory cytokines and oxidative stress, both of which play crucial roles in the progression of the disease. In conclusion, our study suggests that PgEO holds great potential as a natural therapeutic agent for rheumatoid arthritis.

Protein content and antioxidant enzymes activity in reaction wood of poplar and their response to different levels of sustained bending stress

Protein content and antioxidant enzymes activity in reaction wood of poplar and their response to different levels of sustained bending stress

Sequence variants of unknown significance in small fiber neuropathy : Characterization of a heterogeneous patient population

In almost half of patients suffering from small fiber neuropathies (SFN), the etiology remains elusive. For these patients with "idiopathic SFN", symptomatic analgesic therapy is the only option. Reports on apotential genetic background of neuropathic pain syndromes are increasing and particularly in SFN patients, several genetic variants were found mainly located in genes encoding voltage-gated sodium channels. Although up to 30% of SFN patients show genetic alterations, most of these remain of "unknown pathogenic significance" and little is known about "genetic SFN". The study aimed to determine clinical characteristics of SFN patients carrying arare genetic variant of unknown significance in pain-associated genes. From 2015 to 2020, 66patients with primarily idiopathic SFN were examined and rare gene variants of unknown significance detected in 13/66 (20%) of these. Adetailed medical history with focus on pain was recorded and patients filled in standardized questionnaires to assess physical and emotional burden due to pain. The authors found 13/66 (20%) patients with rare variants of unknown significance located in pain-associated genes who reported pain refractory to analgesic treatment, ahigher number of external factors influencing clinical symptoms, and ahigher level of physical impairment and emotional stress due to pain compared with patients without such genetic variants. Early genetic assessment is recommended to optimize the management of patients with potentially hereditary SFN. Early access to rehabilitation and mental support as well as aconsequent elimination of external triggering factors should be granted.

Trait hedonic capacity correlates with sexual pleasure and motives for sexualized drug use in young adults

AbstractAlthough pleasure is a primary motivator for sexual activity, research into the mechanisms facilitating pleasurable sexual experiences is limited. The present research adopts a self-regulatory perspective on sexual pleasure, investigating individuals? capacity to shield hedonic activities from distracting thoughts (trait hedonic capacity) as a correlate of sexual pleasure and sexualized drug use. Study 1 (N?=?247) demonstrates that young adults with higher trait hedonic capacity experience more sexual pleasure and are less prone to cognitive distraction during partnered sexual activities. Pre-registered Study 2 replicates these findings while accounting for demand effects (N?=?182, n?=?86). Expanding on these findings, pre-registered Study 3 (N?=?903) shows that young adults with lower trait hedonic capacity are more inclined to use alcohol as a means of coping with cognitive distraction during sexual activity. Exploratory moderation analyses suggest that this is particularly true for women and individuals with higher levels of stress. In summary, low trait hedonic capacity is associated with lower sexual pleasure and a tendency to use alcohol with the motivation to cope with distracting thoughts during partnered sexual activity.

A Research to Examine the Stress Level and Coping Means Applied by Family Members of Patients With Cancer

One of the main causes of illness and disability worldwide nowadays is cancer. Both first and the second most common cause of mortality in the developed world are cancer-related illnesses. Individuals with a cancer diagnosis constitute a valuable subset within our society. Cancer's effects extend beyond the individual to include family and the community. The stress that caregivers go through is much the same as what cancer patients go through. As they accompany the patients on this journey, the family members are also adjusting to new roles and dealing with personal difficulties that may or may not be connected to the patient's condition. The health of the caregiver is impacted by stress while providing care. The study showed that 34(56.67%) of the samples were female, 23(38.33%) of the samples were in the age group of 29-38years, 49(81.66%) of the samples were married, Spouse were the care takers of cancer patients 25(41.66%), More than half of the caregivers caring the cancer patients for 3-12 months 35(58.33%). Moderate stress was experienced by 49(81.7%)of caregivers and 11(18.3%) of caregivers were experienced severe stress. 35(58.3%) of the caregivers used Adaptive coping strategy and 25 (41.6%) of them used Maladaptive coping strategy. Study concludes that 82% of the caregivers were having moderate stress and majority of the caregivers were using adaptive coping strategies to deal their stress.

Small‐Bandgap Transducers Induced Carrier Separation for In Situ Dual‐Amplified Tumor Oxidative Stress

AbstractThe inherent and unique charge‐carrier release characteristics of piezoelectric sonosensitizers with desired bandgap can be leveraged to initiate reactive oxygen species (ROS) reactions that have considerable potential for sonodynamic therapy (SDT). In this study, a bimetallic Bi4NbO8Br‐polyvinylpyrrolidone (BNOBP) with a small bandgap (2.45 eV) is synthesized as a potential piezoelectric sonosensitizer. The robust interactions within and between the Bi─O and Nb─O layers narrow the bandgap, facilitating carrier transfer. Concurrently, compared with that of TiO2 and BiOBr, BNOBP exhibits a rapid acoustoelectric response and desirable electron–hole separation efficiency, enabling the generation of ·O2− under ultrasound (US) irradiation. Notably, BNOBP alleviates the overexpression of glutathione (GSH) in tumors and prevents the consumption of the generated ROS by GSH. Combining the previous small bandgap endow the high ROS generation efficiency, this study provides a paradigm for in situ regulation of oxidative stress levels in tumor tissue microenvironment based on bimetallic piezoelectric sonosensitizers.

Vestibular system and human cognitive functions

The article is a review of scientific research on the influence of the vestibular system on human cognitive functions. The vestibular apparatus is well studied. Research in recent decades using functional tomography techniques has shown that it has extensive connections with the subcortical and cortical structures of the brain that provide cognitive activity. Hypotheses are put forward that the conduction and processing of bioelectric impulses by the brain, which are recorded by the vestibular apparatus, creates the necessary background for the course of all cognitive processes. The vestibular apparatus has connections with the limbic system, hippocampus, striatum and neocortex. Therefore, vestibular dysfunctions can reduce the ability to learn, cause impaired attention, memory, executive functions, cause disorientation, and affect stress levels. An urgent area of research is the study of the influence of vestibular sensory reactivity on children’s learning ability. This influence has long been underestimated, since it was generally assumed that motor and cognitive development occur independently of each other. The mechanisms linking vestibular dysfunction with cognitive impairment have not yet been sufficiently studied. Further studies are needed to assess the possible impact of vestibular dysfunctions on attention, memory, and speech. Such studies are already underway. Their results are most relevant for patients with neurodegenerative disorders and for children with special needs.

Residential Move During COVID-19 Pandemic and Psychological Health Among College Students: The Role of Perceived Social Support

Research has widely documented the high stress levels posed to college students by the Coronavirus Disease 2019 (COVID-19). However, the role of social support in mitigating the mental health impacts of stressors like residential instability among college students is less well-researched. Using data from a multi-campus online survey of college students’ experiences during the COVID-19 pandemic (n = 2,486), this study examines the role of social support in the association between residential move during COVID-19 pandemic and college students’ reports of depressive symptoms and anxiety. We tested whether perceived social support was more significantly related to depressive symptoms among students who moved in response to COVID-19. The results show significantly higher levels of depressive symptoms and higher prevalence rates of severe anxiety among college students with COVID-19-related move relative to those who did not move during the pandemic. Irrespective of their residential status, college students who received less support than needed during the pandemic had significantly higher levels of depressive symptoms and higher odds of severe anxiety. The findings add to the existing studies showing how the COVID-19 pandemic compounds the problems of depression and anxiety among college students, particularly those experiencing residential instability and with limited social support.

Investigating stress-induced effects on the multifaceted properties of cubic NaTaO3 perovskite oxide: prospects for advanced applications

This study explored the structural, optoelectronic, elastic, mechanical, and thermodynamic behaviour of NaTaO3 cubic perovskite oxide, under varying stress levels. Geometric property analysis reveals a decrease in lattice constants from 4.1 Å to 3.7 Å and cell volume from 71.1–53.4 Å3 as stress increases from 0 to 100 GPa. X-ray diffraction analysis indicated the stable cubic phase with slight peak shifts, demonstrating the material's structural flexibility. Electronic properties revealed an initial increase in the band gap (1.698 eV to 1.936 eV) with applied stress up to 60 GPa, which could be attributed to complex interactions within the material's electronic structure. Optical property analysis suggested that NaTaO3 possessed high optical absorption and conductivity, along with low reflectivity. Furthermore, elastic constants meeting the Born-stability condition (C11 – C12 > 0, C11 + 2C12 > 0, and C44 > 0) confirm the material's mechanical stability. Additional characteristics like the Poisson ratio, Cauchy pressure, and Frantsevich ratio highlighted the ductile and anisotropic nature of NaTaO3. Thermodynamic and phonon dispersion analysis suggested that NaTaO3 can withstand high-stress levels, evidenced by its elevated Debye temperature, indicating superior mechanical stability and increased resistance to thermal degradation. Based on these findings, NaTaO3 proposed as a potential candidate for photovoltaic and thermoelectric devices.

Actomyosin-II protects axons from degeneration induced by mild mechanical stress.

Whether, to what extent, and how the axons in the central nervous system (CNS) can withstand sudden mechanical impacts remain unclear. By using a microfluidic device to apply controlled transverse mechanical stress to axons, we determined the stress levels that most axons can withstand and explored their instant responses at nanoscale resolution. We found mild stress triggers a highly reversible, rapid axon beading response, driven by actomyosin-II-dependent dynamic diameter modulations. This mechanism contributes to hindering the long-range spread of stress-induced Ca2+ elevations into non-stressed neuronal regions. Through pharmacological and molecular manipulations in vitro, we found that actomyosin-II inactivation diminishes the reversible beading process, fostering progressive Ca2+ spreading and thereby increasing acute axonal degeneration in stressed axons. Conversely, upregulating actomyosin-II activity prevents the progression of initial injury, protecting stressed axons from acute degeneration both in vitro and in vivo. Our study unveils the periodic actomyosin-II in axon shafts cortex as a novel protective mechanism, shielding neurons from detrimental effects caused by mechanical stress.