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Polycyclic Aromatic Hydrocarbons (PAHs) exposure has been linked to asthma, but their individual and combined effects in children remain unclear. Using data from the 2003–2012 National Health and Nutrition Examination Survey (NHANES), we investigated the associations between PAHs and asthma through logistic regression, Weighted Quantile Sum (WQS) regression, Quantile g Computation (qg computation), and Bayesian Kernel Machine Regression (BKMR). Subgroup analyses revealed a significant impact of PAHs on asthma, particularly in males. The WQS model showed a marginally significant combined effect of 9 PAHs on asthma (Odds Ratio = 1.37, 95% Confidence Interval: 1.06–1.75). BKMR also indicated a positive association between combined PAH exposure and asthma. 2-Hydroxyfluorene and 1-Hydroxypyrene were identified as the most significant contributors. These findings suggest that mixed PAH exposure is associated with asthma risk in children. [ABSTRACT FROM AUTHOR]

Background: Co-exposure to multiple volatile organic compounds (VOCs) is common in daily life. However, few studies have evaluated the associations between the patterns of simultaneous exposure to multiple VOCs and the risk of hyperuricemia. Methods: This study included 7490 adults from the National Health and Nutrition Examination Survey conducted between 2003 and 2012. The K-means clustering method was applied to cluster eight kinds of VOCs in the blood into various co-exposure patterns, including benzene, bromodichloromethane, chloroform, dibromochloromethane, 1,4-dichlorobenzene, ethylbenzene, methyl tertiary-butyl ether (MTBE), and o-xylene. Binary logistic regression analysis was utilized to assess the association between single VOCs, the co-exposure patterns of multiple VOCs, and the hyperuricemia risk. Restricted cubic spline functions were utilized to investigate the non-linear relationships. Results: Based on eight VOCs, four characteristic co-exposure patterns were generated. Compared with the low-level exposure group, the levels of volatile organic compound (VOC) co-exposure in cluster 2, characterized by relatively high levels of MTBE and moderate levels of bromodichloromethane, chloroform, and dibromochloromethane, were associated with increased hyperuricemia risk, with an odds ratio of 1.32 (1.02, 1.71). Increasing levels of bromodichloromethane and chloroform were significantly associated with an increased risk of hyperuricemia. A strong J-shaped relationship was found between MTBE and hyperuricemia. Conclusions: This study indicated that blood bromodichloromethane and chloroform were positively associated with hyperuricemia risk. Blood MTBE had a J-shaped association with hyperuricemia. In addition, the significant association of the co-exposure patterns of multiple VOCs in the blood with hyperuricemia risk was observed. Changing VOC co-exposure patterns may play a crucial role in the occurrence of hyperuricemia. [ABSTRACT FROM AUTHOR]

It is crucial to investigate the effects of mixtures of contaminants on aquatic organisms, because they reflect what occurs in the environment. Cadmium (Cd) and nickel (Ni) are metals that co‐occur in aquatic ecosystems, and information is scarce on their joint toxicity to Chlorophyceae using multiple endpoints. We evaluated the effects of isolated and combined Cd and Ni metals on multiple endpoints of the chlorophycean Raphidocelis subcapitata. The results showed that Cd inhibited cell density, increased reactive oxygen species (ROS) production (up to 308% at 0.075 mg L−1 of Cd), chlorophyll a (Chl a) fluorescence (0.050–0.100 mg L−1 of Cd), cell size (0.025–0.100 mg L−1 of Cd), and cell complexity in all concentrations evaluated. Nickel exposure decreased ROS production by up to 25% at 0.25 mg L−1 of Ni and Chl a fluorescence in all concentrations assessed. Cell density and oxygen‐evolving complex (initial fluorescence/variable fluorescence [F0/Fv]) were only affected at 0.5 mg L−1 of Ni. In terms of algal growth, mixture toxicity showed antagonism at low doses and synergism at high doses, with a dose level change greater than the median inhibitory concentration. The independent action model and dose‐level–dependent deviation best fit our data. Cadmium and Ni mixtures resulted in a significant increase in cell size and cell complexity, as well as changes in ROS production and Chl a fluorescence, and they did not affect the photosynthetic parameters. Environ Toxicol Chem 2024;43:1855–1869. © 2024 SETAC [ABSTRACT FROM AUTHOR]

The escalating impacts of climate change, particularly ocean acidification and warming, are pivotal stressors for marine ecosystems and have profound effects on biota in polar regions. This study investigated the immunological responses of the Antarctic fish Notothenia rossii to environmental stressors indicative of future ocean conditions under the Intergovernmental Panel on Climate Change Shared Socioeconomic Pathways 5–8.5 scenario for 2100. We exposed N. rossii to conditions simulating present-day conditions: control, elevated temperature, acidification, and both stressors combined over six days. Utilizing RNA-Seq for comprehensive gene expression analysis, we identified significant upregulation and downregulation of immune-related pathways, highlighting a complex interplay of genes involved in complement and coagulation cascades, the intestinal immune network for immunoglobulin A production, cytosolic DNA sensing, natural killer cell-mediated cytotoxicity, and Interleukin 17 signaling pathways. Our findings revealed a predominantly antagonistic gene expression response, suggesting an intricate balance between energy allocation for maintaining homeostasis and the capacity of the immune system to combat stressors. This reflects a potential adaptive mechanism to combined environmental stressors, underscoring the complexity of immune responses in N. rossii and suggesting both potential vulnerabilities and resilience in the face of climate change. This study provides critical insights into the immunological impacts of acidification and warming on Antarctic marine species, emphasizing the need for further research to unravel the mechanisms underlying these observed changes and inform conservation strategies for polar ecosystems in a changing global climate.

Abstract Background Sleep health and obesity may affect the risk of female infertility. However, few studies focused on the interaction of obesity and sleep health on the female infertility risk. This study aimed to evaluate the combined impact of trouble sleeping / sleep duration and overweight/obesity/ abdominal obesity on the risk of female infertility. Methods The data for this cross-sectional study was obtained from National Health and Nutritional Examination Survey, which provided information on trouble sleeping, sleep duration, overweight/obesity, abdominal obesity, and confounding factors. Adopted weighted univariate and multivariate logistic regression models to explore the relationship between trouble sleeping, sleep duration, overweight/obesity, abdominal obesity, and the risk of infertility, respectively, and the combined effect of trouble sleeping and overweight/obesity, trouble sleeping and abdominal obesity, sleep duration and overweight/obesity, sleep duration and abdominal obesity, on the female infertility risk. Results This study included a total of 1,577 women, and 191 were diagnosed with infertility. Women with infertility had a higher proportion of people with overweight/obesity, abdominal obesity, sleep duration ≤ 7 h and trouble sleeping than those with non-infertility. The result indicated that trouble sleeping [odds ratio (OR) = 2.25, 95% confidence intervals (CI): 1.49–3.39], sleep duration ≤ 7 h (OR = 1.59, 95% CI: 1.03–2.48), and the combined impact of abdominal obesity and trouble sleeping (OR = 2.18, 95% CI: 1.28–3.72), abdominal obesity and sleep duration ≤ 7 h (OR = 2.00, 95% CI: 1.17–3.40), overweight/obesity and trouble sleeping (OR = 2.29, 95% CI: 1.24–4.26), and overweight/obesity and sleep duration ≤ 7 h (OR = 1.88, 95% CI: 1.01–3.49) were associated with increased odds of infertility, respectively. Conclusion There was combined effects of trouble sleeping/sleep duration ≤ 7 h and overweight/obesity/ abdominal obesity on increased odds of female infertility.

Abstract Background As a primary form of work-related violence in the healthcare sector, patient mistreatment negatively impacts nurses’ well-being. To date, there has yet reached a definitive conclusion on the mediating mechanism and boundary conditions behind the influence of patient mistreatment on nurses’ emotional exhaustion. Methods This study employed a convenience sampling method to recruit a sample of 1672 nurses from public hospitals in Western China. The data were collected through anonymous self-report questionnaires and analyzed using hierarchical regression and conditional processes to investigate a theoretical framework encompassing patient mistreatment, emotional exhaustion, social sharing of negative events, organizational support, and trait resilience. Results Patient mistreatment led to emotional exhaustion among nurses (β = 0.625, p

Background: Sleep health and obesity may affect the risk of female infertility. However, few studies focused on the interaction of obesity and sleep health on the female infertility risk. This study aimed to evaluate the combined impact of trouble sleeping / sleep duration and overweight/obesity/ abdominal obesity on the risk of female infertility. Methods: The data for this cross-sectional study was obtained from National Health and Nutritional Examination Survey, which provided information on trouble sleeping, sleep duration, overweight/obesity, abdominal obesity, and confounding factors. Adopted weighted univariate and multivariate logistic regression models to explore the relationship between trouble sleeping, sleep duration, overweight/obesity, abdominal obesity, and the risk of infertility, respectively, and the combined effect of trouble sleeping and overweight/obesity, trouble sleeping and abdominal obesity, sleep duration and overweight/obesity, sleep duration and abdominal obesity, on the female infertility risk. Results: This study included a total of 1,577 women, and 191 were diagnosed with infertility. Women with infertility had a higher proportion of people with overweight/obesity, abdominal obesity, sleep duration ≤ 7 h and trouble sleeping than those with non-infertility. The result indicated that trouble sleeping [odds ratio (OR) = 2.25, 95% confidence intervals (CI): 1.49–3.39], sleep duration ≤ 7 h (OR = 1.59, 95% CI: 1.03–2.48), and the combined impact of abdominal obesity and trouble sleeping (OR = 2.18, 95% CI: 1.28–3.72), abdominal obesity and sleep duration ≤ 7 h (OR = 2.00, 95% CI: 1.17–3.40), overweight/obesity and trouble sleeping (OR = 2.29, 95% CI: 1.24–4.26), and overweight/obesity and sleep duration ≤ 7 h (OR = 1.88, 95% CI: 1.01–3.49) were associated with increased odds of infertility, respectively. Conclusion: There was combined effects of trouble sleeping/sleep duration ≤ 7 h and overweight/obesity/ abdominal obesity on increased odds of female infertility. [ABSTRACT FROM AUTHOR]

Co-exposure soil studies of pollutants are necessary for an appropriate ecological risk assessment. Here, we examined the effects of two-component mixtures of metal oxide nanoparticles (ZnO NPs or goethite NPs) with the insecticide chlorpyrifos (CPF) under laboratory conditions in short-term artificial soil assays using Eisenia andrei earthworms. We characterized NPs and their mixtures by scanning electron microscopy, atomic force microscopy, dynamic light scattering and zeta potential, and evaluated effects on metal accumulation, oxidative stress enzymes, and neurotoxicity related biomarkers in single and combined toxicity assays. Exposure to ZnO NPs increased Zn levels compared to control in single and combined exposure (ZnO NPs + CPF) at 72 h and 7 days, respectively. In contrast, there was no indication of Fe increase in organisms exposed to goethite NPs. One of the most notable effects on oxidative stress biomarkers was produced by single exposure to goethite NPs, showing that the worms were more sensitive to goethite NPs than to ZnO NPs. Acetylcholinesterase and carboxylesterase activities indicated that ZnO NPs alone were not neurotoxic to earthworms, but similar degrees of inhibition were observed after single CPF and ZnO NPs + CPF exposure. Differences between single and combined exposure were found for catalase and superoxide dismutase (goethite NPs) and for glutathione S-transferase (ZnO NPs) activities, mostly at 72 h. These findings suggest a necessity to evaluate mixtures of NPs with co-existing contaminants in soil, and that the nature of metal oxide NPs and exposure time are relevant factors to be considered when assessing combined toxicity, as it may have an impact on ecotoxicological risk assessment. [ABSTRACT FROM AUTHOR]

It has been confirmed that microplastics (MPs) are present in the environment. This study simulated secondary PE-MPs via aging and mechanical processes to evaluate their effects on Pak choi (Brassica rapa L.) over 21 d. Two common pollutants, dichlorodiphenyltrichloroethane (DDT) and naphthalene, were used in the combined toxicity tests. The results indicated that the growth of Pak choi was significantly inhibited after exposure to secondary PE-MPs, and the combined effects were antagonistic, owing to the adsorption capacity of secondary PE-MPs to DDT and naphthalene. Oxidative stress in Pak choi can be markedly affected, leading to oxidative damage to plant cells. The moisture content, soil bulk density, soil density, cation exchange capacity (CEC), and FDA hydrolase in the planted soils increased in the treated groups, and the TOC content changed significantly. We also found that the microbial composition of the soil in the DDT and naphthalene groups showed more significant alterations than that in the other groups. Alpha diversity analysis showed that species diversity increased in the combined groups but indicated a clear downward trend in the single MPs groups. This study suggests that secondary PE-MPs harm the growth of Pak choi and can change soil properties, revealing the harm to the ecosystem of MPs in the soil. [ABSTRACT FROM AUTHOR]

Background: As a primary form of work-related violence in the healthcare sector, patient mistreatment negatively impacts nurses' well-being. To date, there has yet reached a definitive conclusion on the mediating mechanism and boundary conditions behind the influence of patient mistreatment on nurses' emotional exhaustion. Methods: This study employed a convenience sampling method to recruit a sample of 1672 nurses from public hospitals in Western China. The data were collected through anonymous self-report questionnaires and analyzed using hierarchical regression and conditional processes to investigate a theoretical framework encompassing patient mistreatment, emotional exhaustion, social sharing of negative events, organizational support, and trait resilience. Results: Patient mistreatment led to emotional exhaustion among nurses (β = 0.625, p <.001), and social sharing of negative events mediated this positive relationship (effect = 0.073, SE = 0.013). The combined effects of organizational support and resilience moderated the mediating effect of the social sharing of negative events between patient mistreatment and emotional exhaustion (β=-0.051, p <.05). Specifically, nurses with a high level of resilience would benefit from organizational support to alleviate emotional exhaustion caused by patient mistreatment. Conclusions: This study validated a significant positive association between patient mistreatment and emotional exhaustion, which aligns with previous research findings. Integrating conservation of resources theory and goal progress theory, we addressed previous contradictory findings on the impact of social sharing of negative events on emotional exhaustion. Social sharing of negative events served as a mediator between patient mistreatment and emotional exhaustion. Additionally, the moderating effect of organizational support on the relationship between social sharing of negative events and emotional exhaustion depended on individual trait of resilience. [ABSTRACT FROM AUTHOR]

Exploring the impact of complex urban morphology on the urban heat island (UHI) effect is essential for sustainable environmental management and enhancing human well-being. This study explored the combined cooling effect of street canyon geometry and the surrounding built environment using a CatBoost model and the Shapley method. The findings indicated that in streets with low building height and density, a high proportion of sky and vegetation and a flatter skyline are conductive to mitigate UHI effect. In streets with high building height and density, a lower proportion of sky and vegetation, and a well-proportioned skyline, can effectively mitigate UHI effect. Regardless of the building density and height around the street, street trees are the optimal choice for greening construction and improvement of large and medium-sized cities in China, given their high controllability and the current urban stock background. Therefore, reasonable control and allocation of street trees can effectively adjust the street canyon geometry, providing suitable cooling strategies for streets with different surrounding built environments. This study proposed a method to mitigate the UHI effect through street canyon geometry, which can be extended to other high-density urban thermal environment studies and guide policymakers on street construction and urban design. [ABSTRACT FROM AUTHOR]

Context: High temperature and oil pollution are typical examples of environmental stress to sea cucumber (Apostichopus japonicus) in northern China. Aims: Evaluate the combined effects of high temperature and oil pollution on the immune responses of sea cucumbers. Methods: In this study, we investigated the immune responses in the respiratory tree of sea cucumber subjected to the optimal temperature (16°C), high temperature (26°C), Oman crude oil (OCO) water-accommodated fractions (WAF) at 16°C (WAF + 16°C) and OCO WAF at 26°C (WAF + 26°C) for 48 h. Key results: All three treatments significantly up-regulated total antioxidant capacity and disturbed active oxygen species homeostasis in sea cucumbers. Moreover, all three treatments caused immune-enzyme activity disorders, manifested by a significant increase in acid–alkaline phosphatase and nitric oxide synthase activities and a noticeable decline in lysozyme activity. Conclusions: Combining the integrated biomarker-response index (WAF + 26°C > 26°C > WAF + 16°C), the combined stress could result in a more adverse effect on the immune responses of sea cucumbers than do high temperature or oil pollution alone, which might further exacerbate the health challenges for sea cucumbers in response to environmental stress. Implications: This study has provided an insight into the immune impacts in benthic organisms caused by high temperature and oil pollution. We investigated the immune responses in the respiratory tree of sea cucumber (Apostichopus japonicus) to high temperature, oil pollution, and the combined stress of high temperature and oil pollution. We found that acute exposure to oil pollution may have affect the immune function of sea cucumbers, whereas high temperature may exacerbate the health challenges of sea cucumbers subjected to environmental stress. [ABSTRACT FROM AUTHOR]

BackgroundLife events are important risk factors for depression and post-traumatic stress disorder (PTSD). Physical activity is a beneficial behavior to physiological and psychological health. While it has not been reported at present the combined effect of physical activity and life events on individual depression and PTSD, and whether it can alleviate the psychological risks induced by life events.ObjectiveTo comprehensively investigate the current status of life events experiences in Chinese students aged 16–24 years and analyze the combined effects of physical activity and life events on their depression and PTSD.MethodsAn online cross-sectional survey was conducted on physical activity levels, life events experiences, depression and PTSD of 1,552 Chinese students aged 16–24 using short version of International Physical Activity Questionnaire (IPAQ-S), adolescent self-rating life events checklist (ASLEC), PTSD Check List-Civilian Version (PCL-C) and Patient Health Questionnaire Depression Scale. Then, logistic regression equation and stratified analysis were used to explore the combined effects of physical activity and life events on depression and PTSD.ResultsRegression analysis showed that, except for female,

Background: Co-exposure to multiple volatile organic compounds (VOCs) is common in daily life. However, few studies have evaluated the associations between the patterns of simultaneous exposure to multiple VOCs and the risk of hyperuricemia. Methods: This study included 7490 adults from the National Health and Nutrition Examination Survey conducted between 2003 and 2012. The K-means clustering method was applied to cluster eight kinds of VOCs in the blood into various co-exposure patterns, including benzene, bromodichloromethane, chloroform, dibromochloromethane, 1,4-dichlorobenzene, ethylbenzene, methyl tertiary-butyl ether (MTBE), and o-xylene. Binary logistic regression analysis was utilized to assess the association between single VOCs, the co-exposure patterns of multiple VOCs, and the hyperuricemia risk. Restricted cubic spline functions were utilized to investigate the non-linear relationships. Results: Based on eight VOCs, four characteristic co-exposure patterns were generated. Compared with the low-level exposure group, the levels of volatile organic compound (VOC) co-exposure in cluster 2, characterized by relatively high levels of MTBE and moderate levels of bromodichloromethane, chloroform, and dibromochloromethane, were associated with increased hyperuricemia risk, with an odds ratio of 1.32 (1.02, 1.71). Increasing levels of bromodichloromethane and chloroform were significantly associated with an increased risk of hyperuricemia. A strong J-shaped relationship was found between MTBE and hyperuricemia. Conclusions: This study indicated that blood bromodichloromethane and chloroform were positively associated with hyperuricemia risk. Blood MTBE had a J-shaped association with hyperuricemia. In addition, the significant association of the co-exposure patterns of multiple VOCs in the blood with hyperuricemia risk was observed. Changing VOC co-exposure patterns may play a crucial role in the occurrence of hyperuricemia.

Backgrounds: The validity of heart rate variability (HRV) has been substantiated in mental workload assessments. However, cognitive tasks often coincide with physical exertion in practical mental work, but their synergic effects on HRV remains insufficiently established. The study aims were to investigate the combined effects of cognitive and physical load on autonomic nerve functions. Methods: Thirty-five healthy male subjects (aged 23.5 ± 3.3 years) were eligible and enrolled in the study. The subjects engaged in n-back cognitive tasks (1-back, 2-back, and 3-back) under three distinct physical conditions, involving isotonic contraction of the left upper limb with loads of 0 kg, 3 kg, and 5 kg. Electrocardiogram signals and cognitive task performance were recorded throughout the tasks, and post-task assessment of subjective experiences were conducted using the NASA-TLX scale. Results: The execution of n-back tasks resulted in enhanced perceptions of task-load feelings and increased reaction times among subjects, accompanied by a decline in the accuracy rate (p < 0.05). These effects were synchronously intensified by the imposition of physical load. Comparative analysis with a no-physical-load scenario revealed significant alterations in the HRV of the subjects during the cognitive task under moderate and high physical conditions. The main features were a decreased power of the high frequency component (p < 0.05) and an increased low frequency component (p < 0.05), signifying an elevation in sympathetic activity. This physiological response manifested similarly at both moderate and high physical levels. In addition, a discernible linear correlation was observed between HRV and task-load feelings, as well as task performance under the influence of physical load (p < 0.05). Conclusion: HRV can serve as a viable indicator for assessing mental workload in the context of physical activities, making it suitable for real-world mental work scenarios. [ABSTRACT FROM AUTHOR]

Background Globally, hypereutrophic conditions in major water reservoirs used for irrigation purposes, promote the co-existence of cyanotoxins and other pollutants such as linear alkylbenzene sulfonate (LAS). LAS is known to alter the permeability of membranes and promote the uptake of other pollutants by plants. In light of the potential human health risks and prevailing hypereutrophic conditions in some catchments in South Africa, we investigated the combined effects of LAS and microcystins (MCs) on food plants when cyanobacteria infested water is used to irrigate terrestrial crops. Methods To understand the potential risks, pot-culture experiments were conducted to assess the effect of LAS on the accumulation of MCs in Brassica oleracea (cabbage) and Solanum tuberosum (potato) plants. The plants were watered with dam water containing 3.48 mg L -1 of the LAS (sodium dodecyl sulfate) and MCs (MC-LR: 10.47 ± 3.879; 6.158 ± 4.127 for MC-RR and 8.160 ± 2.544 for MC-YR μg L -1) for 20 days. Results The presence of LAS, at environmentally relevant concentrations in the irrigation water, did not enhance the uptake of MCs in the two plants, as demonstrated by statistically insignificant differences in the means of the treatments (with and without LAS). In addition, the presence of LAS, high pH, electrical conductivity (EC), and cyanotoxins in the water did not affect the total chlorophyll or the well-being of the plants. However, in some cases the levels of MCs bioaccumulated by the two plants exceeded the WHO recommended tolerable daily intake (TDI). Conclusions These findings imply that the tested levels of LAS and MCs did not have any synergic effects on the two plant species, but irrigating food crops with such water still poses a human health risk.

Background Globally, hypereutrophic conditions in major water reservoirs used for irrigation purposes, promote the co-existence of cyanotoxins and other pollutants such as linear alkylbenzene sulfonate (LAS). LAS is known to alter the permeability of membranes and promote the uptake of other pollutants by plants. In light of the potential human health risks and prevailing hypereutrophic conditions in some catchments in South Africa, we investigated the combined effects of LAS and microcystins (MCs) on food plants when cyanobacteria infested water is used to irrigate terrestrial crops. Methods To understand the potential risks, pot-culture experiments were conducted to assess the effect of LAS on the accumulation of MCs in Brassica oleracea (cabbage) and Solanum tuberosum (potato) plants. The plants were watered with dam water containing 3.48 mg L-1 of the LAS (sodium dodecyl sulfate) and MCs (MC-LR: 10.47 ± 3.879; 6.158 ± 4.127 for MC-RR and 8.160 ± 2.544 for MC-YR μg L-1) for 20 days. Results The presence of LAS, at environmentally relevant concentrations in the irrigation water, did not enhance the uptake of MCs in the two plants, as demonstrated by statistically insignificant differences in the means of the treatments (with and without LAS). In addition, the presence of LAS, high pH, electrical conductivity (EC), and cyanotoxins in the water did not affect the total chlorophyll or the well-being of the plants. However, in some cases the levels of MCs bioaccumulated by the two plants exceeded the WHO recommended tolerable daily intake (TDI). Conclusions These findings imply that the tested levels of LAS and MCs did not have any synergic effects on the two plant species, but irrigating food crops with such water still poses a human health risk.

An enormous amount of construction and demolition waste is generated globally every year, and it increases disposal costs in landfills. The advantage of adopting crushed concrete aggregate as an alternative cushioning material provides a novel approach for reusing and recycling waste materials. However, a lack of understanding of the dynamic responses of recycled concrete aggregate (RCA) inhibits their potential use. In this study, large-scale field tests are carried out to replicate dynamic impact loading on an instrumented concrete shed that is shielded by a 1 m-thick RCA cushioning layer. Six successive large-scale field boulder impact tests with energy levels reaching 70 kJ are conducted. Two different RCA particle sizes—RS (100–150 mm) and RL (200–250 mm)—are investigated. The results show that up to 82% maximum transmitted load can be reduced if the RL cushioning layer is replaced with RS cushioning layer. This phenomenon is attributed to the force chains composed of small particles that are more susceptible to collapse than large particles. To optimize the load-reduction performance of the RCA cushioning layer, practitioners should adopt a small particle size when considering a single boulder impact. In contrast, after six impacts, the maximum transmitted load for Rs is approximately 4.2 times larger than that for RL. This increased load is caused by the relative particle breakage index (Br) for RL being at least 1.3 times larger than that for Rs. This finding indicates that the amount of crushing RCA particles increases with increasing particle size. This phenomenon induces force chains to collapse more easily, and the transmitted load decreases. An RCA cushioning layer with a large particle size can effectively reduce the transmitted load under the consideration of successive impacts. This implies that the combined effects of particle size and number of successive impacts strongly influence the load distributions exerted on structures shielded by an RCA cushioning layer. Highlights: Six successive large-scale field boulder impact tests with energy levels reaching 70 kJ are conducted. [ABSTRACT FROM AUTHOR]

This study evaluates the single and combined effects of dimethoate (DI) and malathion (MA) on oxidative stress biomarkers in the freshwater mussel Dreissena polymorpha, estimating the potential harm of these pesticides on aquatic ecosystems. Superoxide dismutase (SOD) and catalase (CAT) activities, and glutathione (GSH) and lipid peroxidation (TBARS) levels were determined in D. polymorpha exposed to sublethal concentrations of DI, MA and a combination of the two during 24 and 96 h periods. The results showed that the GSH levels were decreased but the TBARS levels were increased in all the exposure groups after 24 and 96 h compared to the control. It was observed that SOD activity decreased but CAT activity increased in all the DI exposure groups after 24 h compared to the control. At the end of 96 hours, it was observed that CAT and SOD activities increased again in some exposure groups compared to the control. Exposure time also had an effect on biomarkers in different levels. According to the results, the cytotoxicity of DI and MA combination depended on their concentrations. DI or/ and MA, in sub-lethal concentrations, induced oxidative damages in D. polymorpha. Combined exposure of the pesticides can alter their toxicity and may be evidence of increased toxicity and oxidative stress. [ABSTRACT FROM AUTHOR]

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Glyphosate (GLY), the most widely used herbicide in the world, is frequently detected in various environmental matrices, including soil, the foundation of agriculture. In practice, more than 2000 GLY-based herbicide (GBH) products are used, consisting of one or more active ingredients (AIs) and so-called "inert" co-formulants that increase the efficacy of the AIs. However, the focus of ecotoxicological assessments is mainly on AIs, while organisms are exposed to complex pesticide formulations under real-world conditions. Overall, the effects on non-target organisms indicate a broad range of biochemical and physiological modes of action, which contrasts with the general assumption that herbicides are specific and act only on target plants. Both GLY alone and GBHs have unintended side-effects on many terrestrial organisms, including non-target plants, microorganisms, insects, spiders, or earthworms, as well as vertebrates such as amphibians, reptiles, or mammals. One of the triggering mechanisms for these effects is oxidative stress with consequences on biochemical parameters and DNA damage. In addition, disruptions of various physiological, behavioral and ecological processes have been reported. Most studies have examined the short-term effects of a single application of GLY/GBH to a single species. However, the agricultural practice of applying GBHs two to three times during a cultivation season over an extended period of time, the interactions with other pesticides and agrochemicals applied to the same field, and effects on ecological interactions within the field and landscape are rarely considered. In the vast majority of cases, the toxicity of GBHs exceeds the toxicity of GLY, demonstrating that supposedly inert co-formulants are either toxic in their own right or interact and add to the toxicity of AIs. The chemical diversity of different GBHs and the non-disclosure of the co-formulants make it difficult to attribute effects to specific chemical substances within a GBH. Moreover, impurities in GBHs (e.g., heavy metals such as arsenic, chromium, cobalt) pose additional environment and food safety risks. These impacts are even more critical because GBHs are so widely distributed worldwide and interact with other pollutants and environmental stressors. Based on the available literature on terrestrial ecotoxicity, and given the drastic decline in biodiversity, we conclude that the continued high use of GBHs, resulting in increased exposure and risk, cannot be considered ecologically sustainable. [ABSTRACT FROM AUTHOR]

The hyper-eutrophic conditions in impoundments used for irrigation around South Africa’s major cities promote the co-existence of linear alkylbenzene sulfonate (LAS) and other pollutants such as metals. The combined effects of LAS and metals, when such water is used to irrigate crops, has not been properly investigated in light of human health risks and prevailing local conditions. To understand the potential risks, pot-culture experiments were conducted to assess the effect of the LAS, sodium-dodecyl-sulfonate (SDS), on the accumulation of aluminum (Al), manganese (Mn) and strontium (Sr) in Brassica oleracea (cabbage) and Solanum tuberosum (potato) plants. The plants were watered with dam water containing 3.48 mg·L−1 of the LAS (sodium dodecyl sulfonate) and Mn (0.257 mg·L−1), Al (0.6 mg·L−1) and Sr (0.16 mg·L−1) as determined by field surveys, for 20 days. The presence of SDS in the irrigation water at environmentally relevant concentrations did not enhance uptake of Sr, Mn, Al in the two plants, as demonstrated by statistically insignificant differences in the means of the treatments (with and without SDS). In addition, the presence of the metals, high pH, EC and presence of cyanotoxins in the water did not affect total chlorophyll and growth of the plants. These findings imply that the prevailing levels of anionic surfactants such as SDS, metals and other contaminants in the hyper-eutrophic reservoirs pose little risk to crop yields, quality of crops and human health, due to the possible accumulation of these contaminants in irrigated plants. Despite the study reporting no immediate inherent risk to the plants and human health, continuous monitoring of the contaminants in water, soil and irrigated plants is recommended since the conditions, concentrations and other factors can quickly change if the management of the catchment does not improve in the near future. [ABSTRACT FROM AUTHOR]

Faba bean water extract (FBW) and vitamin K3 (VK3) have been demonstrated to improve the muscle textural quality of fish. To better apply these two feed additives in commercial aquaculture setting, four experimental diets (control, commercial feed group; 15% FBW, 15% faba bean water extract group; 2.5% VK3, 2.5% vitamin K3 group; combined group, 15% faba bean water extract + 2.5% vitamin K3 group) were formulated to explore their combined effects of FBW and VK3 on the growth, health status, and muscle textural quality of grass carp. The growth performance, textural quality, intestinal characteristics, and oxidative and immune responses were analyzed on days 40, 80 and 120. The results showed that supplementation with higher doses of FBW and VK3 have no influence on growth-related parameters and immune parameters of grass carp. Notably, compared with the control, fish in the combined group had the highest textural qualities (hardness, chewiness and adhesiveness), followed by those in 15% FBW and 2.5% VK3 groups (P < 0.05). Also, FBW and VK3, to some extent, may lower antioxidative ability of grass carp, as illustrated by lower levels of GSH and CAT in 15% FBW, 2.5% VK3, and combined groups on day 120 (P < 0.05). In addition, enhanced lipase activity was observed in the 15% FBW group. Taken together, the combined supplementation of FBW and VK3 was demonstrated to be a more advanced option than their individual supplementation in a commercial setting owing to the resulting combined effects on both the textural quality and health status of grass carp. [ABSTRACT FROM AUTHOR]

The effects of low-dose radiation that are observed in plant populations in radioactively contaminated areas are variable. One of the reasons is the influence of fluctuating weather conditions and the interaction of radiation with weather factors. This article summarizes results of 12-year research on the viability and radioresistance of greater plantain (Plantago major L.) seed progeny growing in the East Ural Radioactive Trace (EURT) zone and in control (nonradioactive) areas, with consideration of weather conditions' variability. The EURT was formed by the Kyshtym accident, which occurred in 1957 at the Mayak Production Association. Absorbed dose rates of P. major parental plants in the pollution gradient were 14.5–165.9 μGy h−1, which correspond to a low-dose range. Seed progeny quality was evaluated as seed weight, the survival rate, and root length of 21-day seedlings. Interannual variability in the studied parameters was high, and their ranges overlapped between EURT groups of seeds and control groups in most cases. The number of significant correlations between the parameters of seed quality and weather conditions was higher in EURT groups than in control populations. In the control groups of seeds, 88.9% of correlations were negative, whereas in the EURT groups, 78.5% were positive. [ABSTRACT FROM AUTHOR]

Abstract Purpose: Presence of diabetes in glaucoma patients may influence findings while documenting the progression of glaucoma. We conducted the study to compare individual and combined effects of diabetes and glaucoma on macular thickness and ganglion cell complex thickness. Methods: The present study is a cross-sectional analysis of 172 eyes of 114 individuals. The groups were categorized according to the following conditions: glaucoma, diabetes mellitus, both glaucoma and diabetes (`both' group), and none of these conditions (`none' group). Patients with diabetes did not have diabetic retinopathy (DR). We compared retinal nerve fiber layer (RNFL) thickness, ganglion cell complex (GCC) thickness, foveal loss of volume (FLV), and global loss of volume (GLV) among the groups. We used random effects multivariate analysis to adjust for potential confounders. Results: The mean (SD) age of these individuals was 60.7 (10.1) years. The total average RNFL and GCC were significantly lower in the glaucoma group (RNFL: -36.27, 95% confidence intervals [CI]: -42.79 to -29.74; P < 0.05, and GCC: -26.24, 95% CI: -31.49 to -20.98; P < 0.05) and the `both' group (RNFL: -24.74, 95% CI: -32.84 to -16.63; P < 0.05, and GCC: -17.92, 95% CI: -24.58 to -11.26; P < 0.05) as compared with the `none' group. There were no significant differences in the average RNFL values and total average GCC between the diabetes group and the `none' group. The values of FLV and GLV were significantly higher in the `glaucoma' group and the `both' group as compared with the `none' group. The foveal values were not significantly different across these four groups. Among the glaucoma cases, 25% were mild, 30% were moderate, and 45% were severe; there was no significant difference in the proportion of severity of glaucoma between the `glaucoma only' and `both' groups (p=0.32). After adjusting for severity and type of glaucoma, there were no statistically significant differences in the values of average RNFL (6.6, 95% CI: -1.9 to 15.2; P=0.13), total average GCC (3.6, -95% CI: -2.4 to 9.6; P=0.24), and GLV (-3.9, 95% CI: -9.5 to 1.6; P=0.16) in the `both group' as compared with the glaucoma only group. Conclusion: We found that diabetes with no DR did not significantly affect the retinal parameters in patients with glaucoma. Thus, it is less likely that thickness of these parameters will be overestimated in patients with glaucoma who have concurrent diabetes without retinopathy.

This study examines the factors affecting the 2m‐temperatures (T2m) in South Korea in winter (DJF) from 1979/1980 to 2018/2019. For this purpose, we performed an empirical orthogonal function (EOF) analysis of the geopotential height at 500 hPa in the region 15°–75°N, 70°E–180° centred around the Korean Peninsula. The first EOF mode, which accounted for 31.1% of the total variance of the winter T2m in the region, is related to the KamChatka Blocking Frequency (KCBF). The second mode, which accounted for 18.3%, is associated with East Asian winter monsoon (EAWM). In addition to EOF analysis, the partial correlation (PC) analysis also confirmed that KCBF Index and EAWM Index, which are highly correlated with the winter T2ms in South Korea, are independent of each other. The individual and combined effects of the KCBF and EAWM are examined because they independently affect the winter T2ms in South Korea. According to the composite analysis, in the years when KCBF is higher than normal (H_KCBF), negative and positive Z500 anomalies are located over the south Sea of Japan and the Kamchatka Peninsula, respectively. In other words, the positive geopotential anomaly over the Kamchatka Peninsula lowers the T2ms of South Korea by blocking the flow of cold air moving eastward from the Korean Peninsula. In the years when a strong EAWM occurred (S_EAWM), negative and positive Z500 anomalies are located over the Manchuria region and the northwestern regions of Russia, respectively. Consequently, cold air in the north moves southward, resulting in lower T2ms in South Korea. For the combined effects of KCBF and EAWM on the T2ms, winters of 40 years are categorized into L_KCBF‐W_EAWM, L_KCBF‐S_EAWM, H_KCBF‐W_EAWM and H_KCBF‐S_EAWM years. The analyses show that when KCBF and EAWM are in phase, the T2ms in South Korea are more prominent than when they are out‐of‐phase. [ABSTRACT FROM AUTHOR]

Studying the impact of various factors on environmental perception is crucial because humans live in an environment where these factors interact and blend. The thermal-acoustic environment is the major factor that affects the overall perception of urban parks. This study focuses on urban parks in the subtropical region, with Xihu Park in Fuzhou, China, as the research area. Through measurements and questionnaires, this study explores the effects of the thermal-acoustic environment in urban parks on subjective evaluation (thermal assessment, acoustic assessment, and overall environmental assessment). The results reveal that: (1) a higher temperature significantly increases the sensation of heat and lowers thermal comfort, heat acceptance, and overall thermal environment evaluation scores. The type of sound source has a significant positive impact on thermal assessment, and the higher the ranking of the sound source type, the greater its positive impact on thermal assessment. (2) Regarding acoustic evaluation, higher sound pressure level is associated with more negative subjective ratings of loudness, harshness, intensity, and excitement. In contrast, positive sound sources can enhance comfort, preference, disorder, coordination, and overall soundscape evaluation. Additionally, temperature increases tend to result in more negative harshness, intensity, and coordination ratings. The interaction between temperature and sound pressure level also significantly affects subjective loudness, harshness, and intensity. (3) Overall environmental evaluation is also affected by temperature, with increasing temperatures leading to decreased comfort and satisfaction while increasing irritation. High sound pressure environments result in worse overall irritation ratings, while positive sound sources can significantly enhance overall comfort, irritation, and satisfaction ratings. Furthermore, the interaction between temperature and sound pressure level significantly impacts overall irritation and satisfaction ratings. These findings are significant for managing and improving the park's thermal environment and soundscape, providing a practical framework for landscape architects. [ABSTRACT FROM AUTHOR]

Great efforts have been made so far to evaluate the influence of nanomaterials (NMs) on aquatic organisms, however, co-exposure of NMs and other pollutants on microalgae has remained largely unstudied. In this regard, the present study first investigated the biological responses of Dunaliella salina to different concentrations of multi-wall carbon nanotubes (MWNTs) and cadmium, separately. Furthermore, the influence of Gum Arabic (GA)-modified MWNTs was also explored on the microalgae. Following this, D. salina was co-exposed to low concentrations (5 mg L−1) of uncoated and GA-coated MWNTs with 300 µM Cd to evaluate the effects and underlying mechanism of MWNTs on metal toxicity. Results showed a growth inhibition in culture media containing uncoated MWNTs. The observed toxicity disappears when MWNTs coated with GA. The toxicity of uncoated MWNTs to D. salina can be ascribed to higher algal cells-nanoparticles (NPs) hetero-aggregation, higher lipid peroxidation, and lower content of the non-enzymatic antioxidants. In addition, shading effect was one of the main reasons for the rise in the chlorophyll content of microalgae exposed to uncoated MWNTs. It was found that both uncoated MWNTs and Cd2+ could inhibit growth of D. salina. However, the introduction of GA-coated MWNTs mitigated the adverse effects of Cd on microalgae, as indicated by algal growth, lipid peroxidation, and non-enzymatic antioxidant component. Adsorption of Cd on GA-coated MWNTs was responsible to attenuate the cadmium toxicity by adding MWNTs. Altogether, these findings bring out the possibility of GA reducing the toxicity of MWNTs and cadmium, making it an ideal capping agent. [ABSTRACT FROM AUTHOR]

Study region: The Fuhe River Basin in Jiangxi Province, China. Study focus: Global climate change and intensified human activities are making the hydrological processes at Fuhe River Basin experiencing dramatic changes. Although some studies have investigated their individual impacts on basin-scale water resources, their combined effects on hydrology have received little attention. In this study, future scenarios were constructed for three future periods, based on five global climate model outputs (GCMs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6) and a dataset of future land use projections under three shared socioeconomic pathways and representative concentration pathways (SSP-RCPs). Then, the Soil and Water Assessment Tool (SWAT) model was used to assess the relative changes in water balance components and extreme flow frequency under these developed scenarios. Furthermore, the hydrological response assessment methodology was improved from the original multiscenario ensemble flow forecast (MESF) framework, which not only strengthens the connection between climate and land use input changes but also adds more assessment items. New hydrological insights for the region: The flow at the outlet of Fuhe River Basin is expected to increase by approximately 27.1%− 30.2%, 24.7–39.0% and 35.5%− 43.5% in the 2030 s, 2060 s and 2090 s, respectively. Water availability will increase significantly in February, August and October and decrease in November and December. To the end of 21st century, surface runoff will have more than 100% increase. Future floods and droughts will be more frequent and severe under SSP5–8.5.

Growing evidence links long-term air pollution exposure with renal function. However, little research has been conducted on the combined effects of air pollutant mixture on renal function and multiple mediation effects of metabolic risk factors. This study enrolled 8996 adults without chronic kidney disease (CKD) at baseline from the CHCN-BTH cohort study. Three-year exposure to air pollutants [particulate matter ≤ 2.5 µm (PM2.5), PM10, PM1, ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO)] and PM2.5 components [black carbon (BC), ammonium (NH4+), nitrate (NO3-), sulfate (SO42-) and organic matter (OM)] were assessed using well-validated machine learning methods. Linear mixed models were applied to investigate the associations between air pollutants and estimated glomerular filtration rate (eGFR). Quantile G-computation was used to assess the combined effects of pollutant mixtures. Causal mediation analysis and Bayesian mediation analysis were employed to estimate the mediation effects of metabolic risk factors. An interquartile range increases in BC (−0.256, 95 %CI: −0.331, −0.180) and OM (−0.603, 95 %CI: −0.810, −0.397) were significantly associated with eGFR decline; while O3 (1.151, 95 %CI: 0.813, 1.489), PM10 (0.721, 95 %CI: 0.309, 1.133), NH4+ (0.990, 95 %CI: 0.638, 1.342), and NO3- (0.610, 95 %CI: 0.405, 0.815) were associated with higher eGFR. The combined effect of the PM2.5 component mixture was found to be associated with lower eGFR (−1.147, 95 % CI: −1.456, −0.839), with OM contributing 72.4 % of the negative effect. Univariate mediation analyses showed that high-density lipoprotein (HDL) mediated 7.1 %, 6.9 %, and 6.1 % effects of O3, BC, and OM, respectively. However, these mediation effects were not significant in Bayesian mediation analysis. These findings suggest the effect of the PM2.5 component mixture on eGFR decline and the strong contribution of OM. Metabolic risk factors may not mediate the effects of air pollutants. Further study is warranted to clarify the potential mechanisms involved.

The relationships between sea levels and single climate indexes have been widely explored. However, sea level is controlled by multiple climate factors simultaneously with differences among places and time scales. Despite this, few studies have addressed the relationships between sea levels and multiple climate indexes. Here, the interrelations between the annual mean sea level (AMSL) and individual climate indexes and combinations of climate indexes were characterized by wavelet coherence (WTC) and multiple wavelet coherence (MWC). The results showed that six climate indexes had a significant correlation with AMSL, among which the Atlantic Multidecadal Oscillation (AMO) had the least significant correlation, but Niño3.4 had the significant correlation. The average significant coherence area (PASC) value for Niño3.4 was 14.03% and its average wavelet coherence (AWC) value was 0.79. By combining climate indexes, the average values of PASC and AWC can be significantly increased. The average PASC and AWC values of the five climate index combinations were the largest, 95.87% and 0.965, respectively, followed by four, three, and two index combinations. A single climate index is not sufficient to explain sea level change in North America. Sea level changes in North America require between three and five climate indexes to explain, depending on the region. By calculating PASC and AWC values, this study provides the possibility to understand the impact of the combined effects of multiple climate indexes on AMSL, is of great help to screen the best predictor of sea level, and provides a new method to reveal the complex mechanism of sea level change. HIGHLIGHTS Multiple wavelet coherence is first used to study the relationship between the annual mean sea level and multiple climate indexes.; We determine the optimal climate index combination for the annual mean sea level in North America.; We analyze the multiple time scales and dominant periods of the annual mean sea level in North America.;

Sedentary behavior (SB) and low (insufficient) physical activity (LPA) are two complementary negative factors affecting cardiovascular health. Most of the current studies are devoted to the study of SB and physical activity (PA) of different intensity separately, while their combined effect has not been studied enough. The purpose was to analyze the literature on the assessment of combined SB+PA effect of different intensity on the general and cardiovascular health of a person. When preparing the review, a search was made for publications in the MedLine, Cochrane, Scopus databases, as well as electronic resources e-library, CyberLeninka and libraries of physical culture and sports universities in Russia for 2002-2022.Issues related to various SB+PA combinations and their effects on general and cardiovascular health are considered and discussed. The facts of the favorable effect of switching sedentary behavior on the same time moderate-intensity PA are presented. The presented data indicate the need for further study, taking into account the mutual substitution of SB and FA of different intensity.

Even though the toxic effects of antibiotics and heavy metals have been extensively studied in the last decades, their combined adverse impact on aquatic organisms is poorly understood. Therefore, the objective of this study was to assess the acute effects of a ciprofloxacin (Cipro) and lead (Pb) mixture on the 3D swimming behavior, acetylcholinesterase (AChE) activity, lipid peroxidation level (MDA—malondialdehyde), activity of some oxidative stress markers (SOD—superoxide dismutase and GPx—glutathione peroxidase), and the essential elements content (Cu—copper, Zn—zinc, Fe—iron, Ca—calcium, Mg—magnesium, Na—sodium and K—potassium) in the body of zebrafish (Danio rerio). For this purpose, zebrafish were exposed to environmentally relevant concentrations of Cipro, Pb, and a mixture for 96 h. The results revealed that acute exposure to Pb alone and in mixture with Cipro impaired zebrafish exploratory behavior by decreasing swimming activity and elevating freezing duration. Moreover, significant deficiencies of Ca, K, Mg, and Na contents, as well as an excess of Zn level, were observed in fish tissues after exposure to the binary mixture. Likewise, the combined treatment with Pb and Cipro inhibited the activity of AChE and increased the GPx activity and MDA level. The mixture produced more damage in all studied endpoints, while Cipro had no significant effect. The findings highlight that the simultaneous presence of antibiotics and heavy metals in the environment can pose a threat to the health of living organisms. [ABSTRACT FROM AUTHOR]

This study investigates the dominant characteristics of winter Arctic tropospheric thickness (1000–200 hPa), the variations of winter atmospheric circulation in the Northern Hemisphere, and the related winter North Pacific storm track (NPST) variabilities during 1979–2018 under the combined effects of the La Niña events with different periods of Arctic tropospheric thermal conditions. Results show that the leading mode (42.7%) exhibits prominent warm anomalies centered on Greenland and Baffin Bay. The winter Arctic tropospheric thickness experienced a phase shift from a cold period of the Arctic tropospheric temperature in 1979–1999 to the warm period after 2000. During the La Niña events with Arctic tropospheric warm anomalies, a wave train is shown in the mid-high latitudes with alternative anticyclonic, cyclonic, and anticyclonic anomalies over the Ural Mountains, Lake Baikal, and North Pacific, respectively. This atmospheric circulation pattern not only intensifies the linkage between the Arctic and mid-low latitudes but also induces the winter NPST shifting poleward. The possible physical mechanism is attributed to the large-scale circulation change and the local baroclinic energy conversion (BCEC). The enhanced anticyclonic anomaly in the North Pacific alters the climatological mean flow, further influencing the local BCEC through the interaction between the mean flow and eddies. The significantly robust BCEC over the North Pacific possibly induces the poleward shift of winter NPST during the La Niña events under the warm period. [ABSTRACT FROM AUTHOR]

Background: The frequent use of hand-held vibrating tools by construction workers exposes them to hand-transmitted vibration (HTV) and noise. This study investigated the effect of combined exposure to HTV and noise on workers' fatigues under simulated work with a typical building destruction tool. Methods:The repeated measures study was conducted on 40 construction workers exposed to HTV (5 m/s2 rms with frequencies of 31.5, 63, and 125 Hz), HTV (10 m/s2 rms-31.5 Hz), noise (90 dBA), and concurrent exposure (noise (90 dBA) + HTV (10 m/s2 rms-31.5 Hz)) with the typical vibrating hand-held tool for 30 minutes. Electromyography signals determined each worker's fatigue level in the Flexor digitorum superficialis (FDS) muscle in two pre-and post-exposure periods. The subjects also filled out the visual analog scale to evaluate mental fatigue severity subjectively. Results:The mean difference of muscle fatigue parameters was significant in all scenarios except for the two scenarios of alone exposure to HTV (5 m/s2 -125 Hz) and noise exposure (p-value < 0.05). The mean difference of mental fatigue in all scenarios except for the two scenarios of exposure to HTV (5 m/s2 -125 Hz) and exposure to HTV (5 m/s2 -63 Hz) was significant (p-value < 0.05). The most differences in muscle fatigue parameters (Amplitude = 8.16±5.63, Mean frequency=-4.69±3.78) and mental fatigue (4.97±2.38) were observed in the simultaneous exposure to noise and HTV. Conclusion: Noise exposure alone cannot produce remarkable effects on muscle fatigue but can aggravate the effects of vibrations as a consequence of synergistic interaction. However, the role of noise on perceived mental fatigue was more dominant than the HTV. These findings should be considered to adapt the existing exposure limits to actual work conditions. [ABSTRACT FROM AUTHOR]

Dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) are mainly released as by-products of human activities, often in the form of mixtures, and the potential harm on human health deserves attention. Therefore, our study aimed to analyze the combined effect of dioxins and DL-PCB exposures on hypertension (HTN) among US adults. Data of eligible participants were acquired from the National Health and Nutrition Examination Survey (NHANES). Multiple logistic regression models with adjustment for covariates were applied to explore the associations between 13 persistent organic pollutants (POPs) and HTN. Stratified analyses and interaction analyses were then conducted by age and gender. Finally, the combined effects of dioxins and DL-PCBs on HTN were assessed by the weighted quantile sum (WQS) model and the Bayesian kernel machine regression (BKMR) model. A total of 976 adults were included in our study, of whom 397 had HTN. Spearman correlations indicated positive correlations among 13 POPs. And most of them (except PCB28, PCB66, and 1,2,3,4,7,8,9-hpcdf) had significant effects on HTN. The result of WQS revealed that mixed exposure to dioxins and DL-PCBs was significantly associated with increased risk of HTN (OR: 2.205; 95% CIs: 1.555, 3.127). The BKMR model also presented a positive trend of HTN risk with exposure to multiple dioxins and DL-PCBs. And 1,2,3,4,6,7,8,9-ocdd may be the main factor for this positive association. Considering the limitations of our cross-sectional study with the small sample, further prospective studies are necessary to validate our findings. [ABSTRACT FROM AUTHOR]

Evidence for the multifaceted responses of terrestrial ecosystems has been shown by the weakening of CO2 fertilization-induced and warming-controlled productivity gains. The intricate relationship between vegetation productivity and various environmental controls still remains elusive spatially. Here several inherent preponderances make China a natural experimental setting to investigate the interaction and relative contributions of five drivers to gross primary productivity for the period from 1982 to 2018 (i.e., elevated atmospheric CO2 concentrations, climate change, nutrient availability, anthropogenic land use change, and soil moisture) by coupling multiple long-term datasets. Despite a strikingly prominent enhancement of vegetation productivity in China, it exhibits similar saturation responses to the aforementioned environmental drivers (elevated CO2, climatic factors, and soil moisture). The CO2 fertilization-dominated network explains the long-term variations in vegetation productivity in humid regions, but its effect is clearly attenuated or even absent in arid and alpine environments controlled by climate and soil moisture. Divergence in interactions also provides distinct evidence that water availability plays an essential role in limiting the potential effects of climate change and elevated CO2 concentrations on vegetation productivity. Unprecedented industrialization and dramatic surface changes may have breached critical thresholds of terrestrial ecosystems under the diverse natural environment and thus forced a shift from a period dominated by CO2 fertilization to a period with nonlinear interactions. These findings suggest that future benefits in terrestrial ecosystems are likely to be counteracted by uncertainties in the complicated network, implying an increasing reliance on human societies to combat potential risks. Our results therefore highlight the need to account for the intricate interactions globally and thus incorporate them into mitigation and adaptation policies. [ABSTRACT FROM AUTHOR]

Although Crassostrea nippona and C. gigas are occasionally found to be sympatric, little is known about the differences in tolerance against environmental stresses between species, which may potentially result in severe economic losses due to the neglect of species-specific biological characteristics in farming practices. Therefore, two independent and consecutive experiments were performed to evaluate the differences in temperature and salinity tolerance between C. nippona and C. gigas spat and determine the optimal environmental conditions for the aquaculture of C. nippona spat. The experimental results of dynamic treatment showed that the accumulative survival rate (ASR) of C. nippona spat was generally lower than that of C. gigas throughout temperature changes and salinity decreases, while the ASR of C. nippona spat was superior to that of C. gigas with increasing salinity. In addition, the daily growth rate (DGR) of both species was significantly inhibited at 18 °C and peaked at 25 °C with increasing temperature (p < 0.05) at each experimental salinity. At 32 °C, the survival rate (SR) of C. nippona spat was significantly lower than that of C. gigas on day 10 at all salinities tested (p < 0.05), whereas the difference in the SR between species at 35 psu gradually disappeared with prolonged stress time. The data indicated that C. gigas spat was suitable for rearing at temperatures of 25 and 32 °C at all salinity levels, except the combination of 32 °C and 35 psu. By contrast, combinations of 25 °C and salinities of 21–35 psu were considered as the optimal environmental conditions for the long-term culture of C. nippona spat. These present findings contribute to a better understanding of the tolerance of C. nippona spat to environmental stresses and suggest that particular attention should be paid to the inferior adaptability of C. nippona when farming in locations outside their natural habitats. [ABSTRACT FROM AUTHOR]

The potential toxicity of microplastics (MPs) and UV filter Benzophenone-4 (BP4) to aquatic organisms has caused widespread concern among the public. However, the combined effects of MPs and BP4 on aquatic organisms are not well understood. This study sought to examine the combined impacts of 10 μg/L BP4, 1 mg/L Polystyrene (PS, 10 μm), and a mixture of both on the feeding, behavior, growth, and reproduction of Daphnia magna (D. magna) over a period of 21 days. The results showed that the combined exposure led to a reciprocal facilitation of bioaccumulation, along with a decrease in the second antenna beats frequency in D. magna. While the co-exposure did not change the body size or growth rate of D. magna , it did affect their feeding efficiency, leading to a decrease in Chlorella ingestion within a 24-h period. Furthermore, there was a high occurrence of malformations in two generations of D. magna exposed to BP4 and PS. The combined exposure also negatively affected reproductive parameters, such as the cumulative number of neonates and the days of first brood, suggesting a decline in overall reproductive success possibly due to feeding inhibition, with available energy potentially being redistributed between reproduction and growth in the daphnids. Co-exposure to BP4 and PS also led to elevated levels of Reactive Oxygen Species (ROS), Malonydialdehyde (MDA), and Glutathione (GSH) levels, as well as mRNA levels related to reproduction, growth, and detoxification in D. magna. Overall, this study delved into the consequences of BP4 and PS on bioaccumulation, feeding, behavior, growth, and reproduction, demonstrating that simultaneous exposure to BP4 and PS could pose a synergistic ecological hazard, potentially threatening aquatic organisms. These findings are critical and should be taken into account for accurate environmental risk assessments. [Display omitted] • Co-exposure to benzophenone-4 (BP4) and polystyrene (PS) could reciprocally enhance their accumulation in Daphnia magna (D. magna). • Co-exposure caused a decrease in motor activity and feeding efficiency. • Co-exposure induced a reduction in reproductive capacity in the F0 generation. • Co-exposure to BP4 and PS led to malformations in D. magna spanning two generations. • Combined effects is a consequence of oxidative stress and changes in related genes. [ABSTRACT FROM AUTHOR]

Deoxynivalenol (DON) is a kind of widespread traditional Fusarium mycotoxins in the environment, and its intestinal toxicity has received considerable attention. Recently, the emerging Fusarium mycotoxin enniatins (ENNs) have also been shown to frequently coexist with DON in animal feed and food with large consumption. However, the mechanism of intestinal damage caused by the two mycotoxins co-exposure remains unclear. In this study, Caco-2 cell line was used to investigate the combined toxicity and potential mechanisms of four representative ENNs (ENA, ENA 1 , ENB, and ENB 1) and DON. The results showed that almost all mixed groups showed antagonistic effects, particularly ENB at 1/4 IC 50 (CI = 6.488). Co-incubation of ENNs mitigated the levels of signaling molecule levels disrupted by DON, including reactive oxygen species (ROS), calcium mobilization (Ca2+), adenosine triphosphate (ATP). The differentially expressed genes (DEGs) between the mixed and ENB groups were significantly enriched in the Ras/PI3K/Akt signaling pathway, including 28 up-regulated genes and 40 down-regulated genes. Quantitative real-time PCR further confirmed the lower expression of apoptotic gene in the mixed group, thereby reducing the cytotoxic effects caused by DON exposure. This study emphasizes that co-exposure of ENNs and DON reduces cytotoxicity by regulating the Ras/PI3K/Akt signaling pathway. Our results provide the first comprehensive evidence about the antagonistic toxicity of ENNs and DON on Caco-2 cells, and new insights into mechanisms investigated by transcriptomics. [Display omitted] • Co-exposure of ENNs and DON reduces cytotoxicity of Caco-2 cells. • Coexistence of mycotoxins mitigated intracellular signaling molecules fluctuations. • The mixed group had high similarity with the DON group on transcriptomics profiles. • The Ras/PI3K/Akt signaling pathway was involved in the antagonism. [ABSTRACT FROM AUTHOR]

The electric superchargers driven by a high-speed motor instead of exhaust gas to operate the compressor have excellent transient characteristics and can effectively reduce the turbo lag of diesel engines. To develop an optimal control strategy for the electric superchargers, it is necessary to explore the combined effects of the electric supercharger and turbocharger under transient processes. Therefore, this study investigated the influence of different intervention speed and time of the electric supercharger on the transient performances of a turbocharged diesel engine. The combined effects of the electric supercharger and turbocharger were analyzed to optimize control strategy through simulations. Effects of the optimization in control strategies were tested through engine experiments. According to the results, the optimized control strategy (slope control strategy) was able to effectively balance transient responsiveness and stability since the rise time of intake pressure were reduced by 52.5 % compared to the base engine and the fluctuations in intake pressure and engine torque were significantly eliminated. Besides, the slope control strategy achieved the lowest PM and NOx emissions during the transient loading process. • The transient characteristics are greatly improved by the electric supercharger. • The combined effects of the electric supercharger and turbocharger are investigated. • An advanced control strategy of the electric supercharger is developed. • Emissions during the transient process are reduced by the electric supercharger. [ABSTRACT FROM AUTHOR]

The biomarkers of the subchronic toxicity of binary mixtures of food additives sorbic acid and aspartame in concentrations of 50, 100 mg/l and 500, 1000 mg/l, respectively, were studied using plant biotests. A comparative analysis of the indicators such as biomass gain, a level of production of the oxidative stress marker, malondialdehyde (MDA), and dynamics of accumulation of proliferative and cytogenetic disorders was carried out after incubation of Allium cepa roots in the aqueous solutions of these compounds. A significant delay in the root growth (more than 60%) was observed in the combinations of sorbic acid and aspartame of 50/1000 and 100/500 mg/l compared to the control. However, significant differences in the effects on root mass gain were not revealed after analysis of the results of treatment with additives individually and with their mixture. It was found that upon treatment with the mixture of additives, only sorbic acid influenced root mass gain, while the interaction of these compounds was insignificant. An effect of the combined impact of sorbic acid and aspartame on the proliferative activity of meristem cells was more negative than upon treatment in the mono-mode in the similar concentrations. This indicator was affected by both sorbic acid and aspartame; however, the preserving agent again played the leading role. Moreover, the level of proliferation also depended on the effect of the interaction between these additives. The antagonistic effect in regard to the indicator of the oxidative stress was not recorded when treating with the mixture of these additives; although, the MDA level in roots increased more than twice upon individual treatment with sorbic acid, while aspartame, on the contrary, reduced its level by half. The obtained results can be used to monitor and predict early consequences of effects of combinations of sorbic acid and aspartame in the food composition.

Traffic emissions and waste incineration are the main sources of PAHs in urban atmosphere, but their spatially superimposed effects are currently unclear. This study assessed the spatial distribution of PAHs and HPAHs concentrations in the atmosphere of Shenzhen by simulating the spatial and temporal dispersion of PAHs and HPAHs emissions from on-road vehicles and municipal solid waste incinerators (MSWIs). Generally, the concentrations of PAHs and HPAHs were higher on workdays than on weekends due to higher traffic volumes, while the prevailing wind direction of the northeast could cause more widespread dispersion of PAHs and HPAHs within Shenzhen’s atmosphere. After superimposing the spatial distribution of pollutants emitted by vehicles and MSWIs, PAHs within 1000 m downwind of MSWIs are mainly contributed by MSWIs and beyond 1000 m by vehicles. The cancer risk values induced by exposure to PAHs and HPAHs via inhalation in Shenzhen were below the acceptable risk level for males and females in each age group, while adults faced the highest cancer risk, followed by adolescents and children. However, spatially, the cancer risk values were above the priority risk level for adult males in localized high-traffic areas in Futian and Luohu districts.

Purpose of review: The goal of this review is to identify cumulative modeling methods used to evaluate combined effects of exposures to environmental chemicals and social stressors. The specific review question is: What are the existing quantitative methods used to examine the cumulative impacts of exposures to environmental chemical and social stressors on health? Recent findings: There has been an increase in literature that evaluates combined effects of exposures to environmental chemicals and social stressors on health using regression models; very few studies applied other data mining and machine learning techniques to this problem. The majority of studies we identified used regression models to evaluate combined effects of multiple environmental and social stressors. With proper study design and appropriate modeling assumptions, additional data mining methods may be useful to examine combined effects of environmental and social stressors.

Background: The chemokines, CXCL12 and CXCL11, are upregulated in tumors from many organs and control their progression. CXCL12 and CXCL11 affect tumor cell functions by either binding their prime receptors, CXCR4 and CXCR3, respectively, and/or CXCR7 as a common second chemokine receptor. In humans, CXCR3 exists in the functional splice variants, CXCR3A and CXCR3B, which either have pro- or anti-tumor activity, respectively. Despite the intimate crosstalk between the CXCL12- and CXCL11-system, the impact of a combination of CXCL12 and CXCL11 on tumor progression remains vague. Methods: In the present work, we have analyzed CXCL12 and CXCL11 for combined effects on migration, invasion, proliferation, and cytostatic-induced apoptosis of the human tumor cells, A549, A767, A772, DLD-1, and MDA-MB-231. Results: We demonstrate that the mode of interaction differs with respect to cell type and function and allows for either potentiation, attenuation or no changes of cellular responses. The divergent responses are not the result of the distinct use of different CXCL12- and CXCL11-receptors by the respective tumor cells, but in case of cell migration seem to be associated with the activation of p38 signaling pathways. Conclusions: Our findings point to therapeutic limitations of ongoing efforts to selectively target CXCR3, CXCR4, or CXCR7 in cancer patients, and rather favor individualized targeting strategies. [ABSTRACT FROM AUTHOR]

Ocean acidification and warming (OAW) are pressing contemporary issues affecting marine life and specifically calcifying organisms. Here, we investigated the direct effects of OAW on life-history traits of the Pacific oyster Crassostrea gigas , the most cultivated bivalve species worldwide. We also tested whether parental conditioning history shaped the phenotypic characters of their progenies (intergenerational carryover effects). Adult oysters and their offspring were exposed to two temperatures (18°C, +3°C) under ambient pH conditions or under an end-of-century acidification scenario (−0.33 pH unit). In adults, we monitored standard biometric and reproductive parameters, stress response by quantifying neuroendocrine metabolites and gamete quality. In larvae, we measured hatching rate, size, biochemical quality, and behavior. We found that reducing pH reduced growth rate and activated the serotonin system, but increasing temperature attenuated these effects. There was no effect of pH on reproduction at either temperature, and no intergenerational carryover effects. Larval characteristics were similar between treatments, regardless of parental conditioning history. Thus, the Pacific oyster seems robust to changes in pH, and increasing temperature is not an aggravating factor. We emphasize that the use of neuroendocrine indicators holds promise for revealing sublethal impacts of environmental changes. [ABSTRACT FROM AUTHOR]