Impact Of Environmental Stress Research Articles

Influence of Thermal and Chemical Stresses on Thermal Properties, Crystal Morphology, and Mechanical Strength Development of a Sulfur Polymer Composite

The unique properties and sustainability advantages of sulfur polymer cement have led to efforts to use them as alternatives to traditional Portland cement. The current study explores the impact of environmental stresses on the strength development of polymer composite SunBG90, a material composed of animal and plant fats/oils vulcanized with 90 wt. % sulfur. The environmental stresses investigated include low temperature (−25 °C), high temperature (40 °C), and submersion in water, hexanes, or aqueous solutions containing strong electrolyte, strong acid, or strong base. Samples were analyzed for the extent to which exposure to these stresses influenced the thermo-morphological properties and the compressional strength of the materials compared to identical materials allowed to develop strength at room temperature. Differential scanning calorimetry (DSC) analysis revealed distinct thermos-morphological transitions in stressed samples and the notable formation of metastable γ-sulfur in hexane-exposed specimens. Powder X-ray diffraction confirmed that the crystalline domains identified by DSC were primarily γ-sulfur, with ~5% contribution of γ-sulfur in hexane-exposed samples. Compressive strength testing revealed high strength retention other than aging at elevated temperatures, which led to ~50% loss of strength. These findings reveal influences on the strength development of SunBG90, lending important insight into possible use as an alternative to OPC.

Exploring the Role of DNA Methylation in Regulating Gene Expression and Adaptation in Plants: A Case Study on the Impact of Environmental Stress on Gene Regulation

Exploring the Role of DNA Methylation in Regulating Gene Expression and Adaptation in Plants: A Case Study on the Impact of Environmental Stress on Gene Regulation

Advancements and Prospects of Genome-Wide Association Studies (GWAS) in Maize.

Genome-wide association studies (GWAS) have emerged as a powerful tool for unraveling intricate genotype-phenotype association across various species. Maize (Zea mays L.), renowned for its extensive genetic diversity and rapid linkage disequilibrium (LD), stands as an exemplary candidate for GWAS. In maize, GWAS has made significant advancements by pinpointing numerous genetic loci and potential genes associated with complex traits, including responses to both abiotic and biotic stress. These discoveries hold the promise of enhancing adaptability and yield through effective breeding strategies. Nevertheless, the impact of environmental stress on crop growth and yield is evident in various agronomic traits. Therefore, understanding the complex genetic basis of these traits becomes paramount. This review delves into current and future prospectives aimed at yield, quality, and environmental stress resilience in maize and also addresses the challenges encountered during genomic selection and molecular breeding, all facilitated by the utilization of GWAS. Furthermore, the integration of omics, including genomics, transcriptomics, proteomics, metabolomics, epigenomics, and phenomics has enriched our understanding of intricate traits in maize, thereby enhancing environmental stress tolerance and boosting maize production. Collectively, these insights not only advance our understanding of the genetic mechanism regulating complex traits but also propel the utilization of marker-assisted selection in maize molecular breeding programs, where GWAS plays a pivotal role. Therefore, GWAS provides robust support for delving into the genetic mechanism underlying complex traits in maize and enhancing breeding strategies.

Phenological Variation in Chickpea (Cicer arietinum L.) Varieties through Foliar Application of Cytokinin Analogs and Nutrients under Water Deficit Stress

Chickpea (Cicer arietinum L.), a rainfed crop predominantly grown in temperate and subtropical climates, faces significant challenges in production due to terminal drought stress impacting various phenological stages. This study addresses the challenges posed by terminal drought stress on the phenological stage of chickpea varieties viz., JG 36 and JG 14. The experiment was conducted during the Rabi seasons of 2021-2022 and 2022-2023 at the Experimental Research Farm, Seed Technology Research Unit, JNKVV, Jabalpur (M.P), using a split-split plot design with three replications. This research also investigates the impact of foliar applications of cytokinin analogs viz., Thiourea, Thidiazuron, and Benzyladenine and nutrients viz., ZnSO4 and KCl on chickpea under water deficit stress conditions. The results revealed significant differences in days to pod formation, seed formation, physiological maturity, and harvest maturity among the irrigation levels, varieties, and foliar spray of plant growth regulators and nutrients. Under different irrigation levels, D1 (Irrigation at 30 DAS and flower initiation) exhibited delayed phenological stages of the crop, while D2 (Drought stress at flowering up to physiological maturity) showed an early onset of all the phenological stages. Under water deficit conditions, JG 14 exhibited accelerated maturity beyond its typical early maturation in comparison to well-watered conditions, highlighting the impact of environmental stress on varietal responses. With respect to the application of plant growth regulators and nutrients, treatment T12 (TDZ @ 10 ppm + 1% KCl) significantly delayed pod and seed formation, as well as physiological and harvest maturity as compared to untreated control (T1). Foliar application of TDZ @ 10 ppm + 1% KCl (T12) enhanced seed filling duration by 2.59 days compared to the untreated control. Further investigations are needed to identify the impact of Thidiazuron and KCl in enhancing seed yield and seed weight of chickpea under optimal and sub-optimal soil water conditions, to provide recommendations for chickpea growers.

In vitro assessment of the bacterial stress response and resistance evolution during multidrug-resistant bacterial invasion of the Xenopus tropicalis intestinal tract under typical stresses

The intestinal microbiome might be both a sink and source of resistance genes (RGs). To investigate the impact of environmental stress on the disturbance of exogenous multidrug-resistant bacteria (mARB) within the indigenous microbiome and proliferation of RGs, an intestinal conjugative system was established to simulate the invasion of mARB into the intestinal microbiota in vitro. Oxytetracycline (OTC) and heavy metals (Zn, Cu, Pb), commonly encountered in aquaculture, were selected as typical stresses for investigation. Adenosine 5’-triphosphate (ATP), hydroxyl radical (OH·-) and extracellular polymeric substance (EPS) were measured to investigate their influence on the acceptance of RGs by intestinal bacteria. The results showed that the transfer and diffusion of RGs under typical combined stressors were greater than those under a single stressor. Combined effect of OTC and heavy metals (Zn, Cu) significantly increased the activity and extracellular EPS content of bacteria in the intestinal conjugative system, increasing intI3 and RG abundance. OTC induced a notable inhibitory response in Citrobacter and exerted the proportion of Citrobacter and Carnobacterium in microbiota. The introduction of stressors stimulates the proliferation and dissemination of RGs within the intestinal environment. These results enhance our comprehension of the typical stresses effect on the RGs dispersal in the intestine.

Trials for the Control of Isopods Infesting Lake Qarun, Egypt, with the Impact of Environmental Stresses on their Parasitism

Trials for the Control of Isopods Infesting Lake Qarun, Egypt, with the Impact of Environmental Stresses on their Parasitism

Response and Impact of Environmental Stress on Crop Reproduction

Response and Impact of Environmental Stress on Crop Reproduction

Effect of Acute and Cumulative Stress on Gene Expression in Mammary Tissue and Their Interactions with Physiological Responses and Milk Yield in Saanen Goats

This study addresses the hypothesis that different acute stressors can cumulatively decrease milk yield. In fact, in a time of global warming, the impact of environmental stress and farm management practices on milk production remains unclear. In this context, our objective was to investigate the effect of acute and cumulative stress on gene expression in mammary tissue and their interactions with physiological responses and milk yield in Saanen goats. Thirty lactating goats were subjected to two treatments: (1) control (CT), in which goats were maintained following a habitual routine under comfort conditions; (2) stress (ST), in which the goats were subjected to different types of environmental stress: heat stress, adrenocorticotropic hormone administration, hoof care management, and exposure to rain. These stressors were performed sequentially, with one stress per day on four consecutive lactation days, to evaluate their effect on milk quality and milk yield. Our results showed that compared to CT goats, cumulative stress increased the gene expression of glucocorticoid receptor (GR), interferon-gamma (IFN-γ), superoxide dismutase (SOD), and catalase (CAT) in mammary tissue, which are indicators of cortisol action, inflammatory response, and antioxidant enzymes. Furthermore, the acute challenges imposed on ST goats changed their rectal temperature and respiratory frequency and increased cortisol, glucose, cholesterol, triglycerides, and high-density lipoprotein release in plasma when compared to CT goats. Although these physiological and metabolic responses restore homeostasis, ST goats showed lower milk yield and higher somatic cell count in milk than CT goats. In conclusion, the results confirmed our initial hypothesis that different acute stressors cumulatively decrease the milk yield in Saanen goats.

The effects of environmental factors on plant diversity of Darab natural ecosystems in Fars province, Iran.

This research quantitatively evaluated the diversity of plants to protect vulnerable species. To measure vegetation information, the appropriate sampling plot size was determined based on the canopy cover of the dominant species of the study area (1 m2). Then, in each unit, sampling was done along 3 transects of 100m. Along each transect, 10 plots with dimensions of one square meter were placed at a distance of 10m from each other. In each plot, the type, life forms, frequency of plant species, and species density were recorded. Species diversity indices were calculated using Ecological Methodology software. The values obtained from these indicators were analyzed in SPSS 24 statistical software and using the F test. The results of the Analysis of variance (ANOVA) showed that the highest values of the species diversity indices are in the middle altitudes (ecotone) class. ANOVA of the richness, evenness, and heterogeneity indices in different altitude classes showed that the values of the richness indices were not significant, but among the indices related to the heterogeneity, the Hill index and all the evenness indices were significant. Comparing the numerical indices of our communities enables us to determine the impact of environmental stress in a single community to choose the best habitat among a similar group for conservation. A community that has high diversity and richness is important for conservation. Therefore, the authorities must prevent the destruction of the vegetation of the study area in connection with the implementation of principled and correct management by the potential of the region, but also to reduce the pressure of livestock grazing and carry out corrective and restoration operations, to turn these rangelands towards rich diversity.

Contrasting effects of different organic amendments on the microbial responses to extreme temperature changes

Soil organic amendments can change microbial communities, potentially impacting their resilience to environmental stresses and, consequently, their transformation of soil carbon and nitrogen. While several studies have investigated the impact of a few organic amendments on microbial resilience to stresses in the form of absolute change in environmental conditions, the potential stress effects of different rates of change have received much less attention. The rate of change in environmental properties such as temperature may induce different microbial stress responses, given the reliance of microbial defensive mechanisms on time-dependent signalling and activation processes. In this research, we explored the relevance of the rate of temperature change as a microbial stressor and evaluated the potential use of organic amendments in steering soil ecological response. We monitored the changes in microbial properties and concentrations of different carbon and nitrogen fractions to temperature change treatments of 2.5 and 30 °C/d after the application of three commonly available rural organic amendments to a podzol soil in a laboratory incubation study. Results showed significant effects of the temperature treatments on bacterial and total microbial DNA concentrations, as well as on dissolvable and insoluble carbon and nitrogen ratios regardless of the organic amendment treatment. Temperature impacts on respiration rates, priming rates and the concentration of soil hot water extractable carbon and nitrogen differed depending on the organic amendment treatment. Results demonstrated that compost-amended soils were least sensitive to the temperature treatments, while grasses and fermented grasses treatments were generally more sensitive while showing opposite responses. Our findings indicate that organic amendments might be utilized to manipulate the impact of environmental stresses on soil carbon and nitrogen concentrations, and highlight the need for future research to investigate the relevant ecological properties and mechanisms.

Early-Stage Detection of Biotic and Abiotic Stress on Plants by Chlorophyll Fluorescence Imaging Analysis.

Most agricultural land, as a result of climate change, experiences severe stress that significantly reduces agricultural yields. Crop sensing by imaging techniques allows early-stage detection of biotic or abiotic stress to avoid damage and significant yield losses. Among the top certified imaging techniques for plant stress detection is chlorophyll a fluorescence imaging, which can evaluate spatiotemporal leaf changes, permitting the pre-symptomatic monitoring of plant physiological status long before any visible symptoms develop, allowing for high-throughput assessment. Here, we review different examples of how chlorophyll a fluorescence imaging analysis can be used to evaluate biotic and abiotic stress. Chlorophyll a is able to detect biotic stress as early as 15 min after Spodoptera exigua feeding, or 30 min after Botrytis cinerea application on tomato plants, or on the onset of water-deficit stress, and thus has potential for early stress detection. Chlorophyll fluorescence (ChlF) analysis is a rapid, non-invasive, easy to perform, low-cost, and highly sensitive method that can estimate photosynthetic performance and detect the influence of diverse stresses on plants. In terms of ChlF parameters, the fraction of open photosystem II (PSII) reaction centers (qp) can be used for early stress detection, since it has been found in many recent studies to be the most accurate and appropriate indicator for ChlF-based screening of the impact of environmental stress on plants.

Identification and characterization of Prx5 and Prx6 in Chilo suppressalis in response to environmental stress.

The antioxidant proteins, peroxiredoxins (Prxs), function to protect insects from reactive oxygen species-induced toxicity. In this study, two Prx genes, CsPrx5, and CsPrx6, were cloned and characterized from the paddy field pest, Chilo suppressalis, containing open reading frames of 570 and 672 bp encoding 189 and 223 amino acid polypeptides, respectively. Then, we investigated the influence of various stresses on their expression levels using quantitative real-time PCR (qRT-PCR). The results showed expression of CsPrx5 and CsPrx6 in all developmental stages, with eggs having the highest level. CsPrx5 and CsPrx6 showed higher expression in the epidermis and fat body, and CsPrx6 also showed higher expression in midgut, fat body, and epidermis. Increasing concentrations of insecticides (chlorantraniliprole and spinetoram) and hydrogen peroxide (H2 O2 ) increased the expression levels of CsPrx5 and CsPrx6. In addition, the expression levels of CsPrx5 and CsPrx6 were almost markedly upregulated in larvae under temperature stress or fed by vetiver. Thus, CsPrx5 and CsPrx6 upregulation might increase the C. suppressalis defense response by reducing the impact of environmental stress, providing a better understanding of the relationship between environmental stresses and insect defense systems.

The Impact of Environmental Stress on the Secondary Metabolites and the Chemical Compositions of the Essential Oils from Some Medicinal Plants Used as Food Supplements

This study aims to study the impact of environmental stresses on the chemical compositions of essential oils and the content of secondary metabolites of the plants most used by the rural population: Thymus vulgaris, Mentha pulégium and Rosmarinus officinalis. The results of the study indicate that the percentage of secondary metabolites increased in the second year when temperature and water pressure increased by 50%. Specifically, coumarin increased from 3.94% to 9.23%, saponins increased from 6.17% to 7.78%, tannins increased from 2.90% to 6.12%, alkaloids increased from 6.72% to 15.95%, and flavonoids increased from 7.42% to 12.90%. However, in the fourth year, the temperature continued to increase, and water availability decreased by 75%, leading to a decrease in the rate of secondary metabolites. Coumarin decreased from 9.22% to 6.15%, saponin decreased from 7.80% to 6.79%, tannin decreased from 6.11% to 4.16%, alkaloids decreased from 15.95% to 10.45%, and flavonoids decreased from 12.90% to 9.70%. Similar results were observed for the essential oil yield, which increased in year two from 3.57% to 3.84% and decreased in year four to 1.04%. The same pattern was observed for Mentha pulégium and Rosmarinus officinalis. The gas chromatography analysis of the three essential oil samples showed that the majority of the compounds of the three plants were modified under the conditions of climate change. For Mentha pulégium, pulegone was found to represent the highest proportion in sample two (73.3%), followed by sample one (71.1%), and finally, sample three (61.8%). For Rosmarinus officinalis, the majority of compounds were cineole and camphor, with cineole representing 36% in sample two, 45.89% in sample one, and 43.08% in sample three, and camphor representing 21.44% in sample two, 21.56% in sample three, and 17.44% in sample one. For Thymus vulgaris, the majority of the compounds were Thymol and Carvacrol, which underwent approximately the same modifications as the majority of compounds in the other two plants. The results indicate that environmental stresses can lead to significant changes in these compounds, which can affect the medicinal and aromatic properties of these plants. The findings of this study highlight the need for more research to understand the impacts of climate change on plant species and the potential implications for human health and well-being.

Environmental stress, majoritarianism, and social unrest in Europe

ABSTRACT As climate change continues to affect countries worldwide, scholars have begun considering the impact of environmental stress for political instability in industrialized countries. This paper analyzes the risk of social unrest in various European political systems in relation to the interaction of environmental stress and electoral institutions. We use a spatially and temporally disaggregated dataset to examine the possible relationships between environmental stress and social unrest in all European Union member countries from 2000 to 2020. We find that there are stark differences between the observed interaction of majoritarian electoral features and environmentally induced unrest in those European states with a history of Communist rule or climate vulnerability versus the rest of Europe. Overall, these results suggest that electoral systems play an important but heterogenous role in the understanding of climate change and political unrest.

ECOLOGICAL CRISES AND POPULATION PSYCHOLOGY

This article explains the information about the occurrence of a number of negative environmental conditions as a result of the drying of the Aral Sea, the deterioration of living conditions, and the sharp aggressive impact of environmental stress on the behaviour of individuals. that they negatively affect personality traits.

Impact of Environmental Stresses on the Antibacterial Activity of Graphene Oxide (GO) Nanoparticles against P. putida Biofilms.

As the production of graphene-based nanomaterials such as GO is increasing, it is expected that a large amount of GO waste will be generated. The environment (i.e., soil and aquatic systems) will be amongst the final repositories of these wastes which means important natural microbial communities in such environments will be at risk of GO exposure. However, little is known about how these communities respond to environmental stresses in synergy with the presence of GO. In this study, the effect of three different stress conditions: temperature (5, 25 and 40 °C); pH (5 to 9) and osmotic stress (51, 219 and 320 mM NaCl) in addition to GO treatment was investigated on the viability and physiology of biofilms and planktonic cells of soil bacterium P. putida. It was found that planktonic cells were more resistant to GO alone compared to biofilms. However, the cells were sensitive to GO when exposed to pH or osmotic stresses. Temperature was not found to influence the survival of biofilm with or without exposure to GO. However, low pH caused a reduction in colony-forming units (CFU) at pHs 5 and 6 for the pre-treated samples, while biofilms at pH 7-9 did not show any decrease. Interestingly, the post-treatment of planktonic cells or biofilms with GO showed a significant reduction in CFU at all pH ranges. The effect of higher osmotic stress in combination with GO resulted in a significant reduction in biofilms. These results show that the effect of stresses naturally occurring in the environment can be affected and changed when in combination with GO and can potentially affect the balance of natural biofilms.

Solid-State Fermentation of Plant Feedstuff Mixture Affected the Physiological Responses of European Seabass (Dicentrarchus labrax) Reared at Different Temperatures and Subjected to Salinity Oscillation.

This study aimed to evaluate the effects of dietary inclusion of plant feedstuff mixture (PFM) pre-treated by solid-state fermentation (SSF) on the physiological responses of European seabass. For that purpose, two diets were formulated to contain: 20% inclusion level of non-fermented plant ingredients mixture (20Mix) and 20Mix fermented by A. niger in SSF conditions (20Mix-SSF). Seabass juveniles (initial body weight: 20.9 ± 3.3 g) were fed the experimental diets, reared at two different temperatures (21 and 26 °C) and subjected to weekly salinity oscillations for six weeks. Growth performance, digestive enzyme activities, humoral immune parameters, and oxidative stress indicators were evaluated. A reduction in weight gain, feed intake, and thermal growth coefficient was observed in fish fed the fermented diet (20Mix-SSF). Salinity oscillation led to an increase in weight gain, feed efficiency, daily growth index, and thermal growth coefficient, regardless of dietary treatment. Higher rearing temperatures also increased daily growth index. No dietary effect was observed on digestive enzymes activities, whereas rearing temperature and salinity oscillation modulated digestive enzyme activities. Oxidative stress responses were significantly affected by experimental diets, temperature, and salinity conditions. Catalase and glutathione peroxidase activities showed an interactive effect. Fish reared at 21 °C showed higher enzymatic activity when fed the 20Mix-SSF. Conversely, fish reared at 26 °C showed higher GPx activity when fed the 20Mix diet. Fish reared at 26 °C showed reduced peroxidase and lysozyme activities, while salinity fluctuation led to increased lysozyme activity and decreased ACH50 activity. ACH50 activity increased in fish fed the 20Mix-SSF. Overall, the dietary inclusion of PFM fermented by A. niger was unable to mitigate the impact of environmental stress on physiological performance in European seabass. In fact, fermented feed caused an inhibition of growth performances and an alteration of some physiological stress indicators.

Chromatin Immunostaining of Plant Nuclei.

Recent evidence has demonstrated that specific epigenetic changes are also related to plant growth and development. Immunostaining enables the detection and characterization of chromatin modification, e.g., histone H4 acetylation (H4K5ac), histone H3 methylation (H3K4me2 and H3K9me2), and DNA methylation (5mC) with unique and specific patterns in plant tissues. Here we describe experimental procedures to determine the histone H3 methylation (H3K4me2 and H3K9me2) patterns in 3D-chromatin in whole roots tissue and 2D-chromatin in single nuclei in rice. To analyze both iron and salinity treatments, we show how to test for changes to the epigenetic chromatin landscape using heterochromatin (H3K9me2) and euchromatin (H3K4me) markers for chromatin immunostaining, especially in the proximal meristem region. To elucidate the epigenetic impact of environmental stress and external plant growth regulators, we demonstrate how to apply a combination of salinity, auxin, and abscisic acid treatments. The results of these experiments provide insights into the epigenetic landscape during rice root growth and development.

Ten questions concerning the impact of environmental stress on office workers

We regularly face stress during our everyday activities, to the extent that stress is recognized by the World Health Organization as the epidemic of the 21st century. Stress is how humans respond physically and psychologically to adjustments, experiences, conditions, and circumstances in their lives. While there are many reasons for stress, work and job pressure remain the main cause. Thus, companies are increasingly interested in creating healthier, more comfortable, and stress-free offices for their workers. The indoor environment can induce environmental stress when it cannot satisfy the individual needs for health and comfort. In fact, office environmental conditions (e.g., thermal, and indoor air conditions, lighting, and noise) and interior design parameters (e.g., office layout, colors, furniture, access to views, distance to window, personal control and biophilic design) have been found to affect office workers' stress levels. A line of research based on the stress recovery theory offers new insights for establishing offices that limit environmental stress and help with work stress recovery. To that end, this paper answers ten questions that explore the relation between the indoor office-built environment and stress levels among workers. The answers to the ten questions are based on an extensive literature review to draw conclusions from what has been achieved to date. Thus, this study presents a foundation for future environmental stress related research in offices.

The MIS 4 environmental stress impact on hominin occupation in the northwestern Caucasus: New evidence from the Hadjoh 2 site

The Hadjoh 2 open-air site is one of a few Middle Palaeolithic sites known in the northwestern Caucasus, which provide evidence of both the early (MIS 5) and late (MIS 3) stages of the Middle Palaeolithic occupation of the region. The 2020 multidisciplinary research indicates that Hadjoh 2 preserves four distinct Middle Palaeolithic layers, which house the evidence for hominins that produced the Middle Palaeolithic assemblages and visited the site periodically from about 120–100 ka in MIS 5d to about 50–45 ka in MIS 3. At present, Hadjoh 2 is the only Middle Palaeolithic open-air site in the North Caucasus, in which the site's lithostratigraphy and paleoenvironmental conditions were investigated by means of modern-level studies, including palynological and paleopedologic analyses, and magnetic proxy data.