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Air pollution is a major contributor to the global disease burden, especially affecting respiratory and cardiovascular health. However, physical activity is associated with improved lung function, a slower decline in lung function, and lower mortality. The public is more likely to be exposed to air pollution during outdoor physical activity. However, studies on how long-term and short-term exposure to air pollution interacts with physical activity yield inconsistent results, and the thresholds for air pollution and physical activity remain unclear. Thus, more studies are needed to provide sufficient evidence to guide the public to safely engage in outdoor physical activity when exposed to air pollution.

Abstract Dietary exposure to heavy metals and metalloids [metal(loid)s] deserves increased attention; however, there is a lack of a comprehensive understanding of the risks of dietary exposure from multi-type food intake and multi-metal(loid) exposure using a bioaccessibility-corrected method. Here, we determined the concentration and bioaccessibility of six toxic metal(loid)s in six major food groups in an industrial city with intensive smelting activity. By incorporating children’s dietary patterns, the probability distribution of health risks from dietary metal(loid)s exposure was assessed. Marked differences were observed in the dietary exposure characteristics within metal(loid)s and major food groups. Cereal and vegetables were the major food groups local children intake. Cereals, meat, beans, and aquatic products had the highest concentrations of Cu and Cd, Pb and Cr, Ni, and As, respectively. Generally, meat, eggs, and aquatic products exhibited higher bioaccessibility than cereals, beans, and vegetables. The bioaccessibility of metal(loid)s decreased in the following order: Pb > Cr > Cu > Ni > As > Cd. For non-carcinogenic risks, the average hazard index was 7.3, with 99.6% exceeding acceptable levels. Arsenic was the dominant risk element and aquatic product was the main risk source. The aggregated carcinogenic risk was 3.4 × 10–3, with Cr the major risk contributor and cereals and meat the dominant food sources. The findings demonstrated that (1) the metal(loid) dietary exposure risk of children from areas with intensive smelting activities should be taken seriously, and (2) it is necessary to identify the specific food category and metal(loid) based on a comprehensive analysis of the metal(loid) concentration and bioaccessibility, and dietary habits of the population to effectively reduce risk.

In this study, Lactobacillus plantarum (Lp), Lactobacillus fermentum (Lf) and Weissella confusa (Wc) were selected as exogenous strains for the fermentation of sourdough. The growth of lactic acid bacteria, the distribution of major metabolites such as organic acid and sugar, and the distribution of protein in sourdough were evaluated by high performance liquid chromatography (HPLC) and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Finally, the sourdough was applied to the production of frozen dough bread. The results showed that in the sourdough, the bacteria entered the logarithmic growth phase at 4–12 h, and mixed cultures grew better than individual ones, showing synergism. Particularly, the colony count of Lf + Wc in sourdough was as high as 9.18 (lg(CFU/g)) after 12 h fermentation, and a large amount of fructose (11.82 mmol/kg) and extracellular polysaccharide (EPS) (3.132 g/kg) were generated. Compared with the other groups, Lf + Wc exhibited moderate acid production rate, lower protease activity and slower protein degradation rate. The baking quality of bread made from Lf + Wc fermented sourdough frozen and stored for 13 weeks decreased slightly, and the baking loss rate decreased only by 5.3%. In addition, GC-MS analysis showed that the number of volatile compounds in frozen dough bread fermented with Lf + Wc increased by eight after 13 weeks of frozen storage. In conclusion, Lf and Wc have a good synergistic effect when used together. Notably, metabolites such as exopolysaccharides generated during metabolism are of great significance for delaying and controlling the deterioration of frozen dough bread quality. This study provides a certain theoretical basis for the application of multigrain sourdough as a natural antifreeze agent in the large-scale preparation of frozen dough.

Background Immunotherapy-related endocrine adverse reactions are relatively common, which often lead to serious outcomes if not treated in time. However, the incidence of immunotherapy-related endocrine adverse reactions varies widely in previous literature reports without standard processing. Objective To investigate the occurrence and treatment process of endocrinologic adverse reactions caused by immune checkpoint inhibitors (ICIs) in the real world. Methods The clinical data of 204 patients with solid tumors treated with ICIs at the Third People's Hospital of Zhengzhou from January 2019 to March 2022 was retrospectively analyzed, the endocrinologic adverse reactions occured their treatment were observed and standardized management was conducted according to the adverse reactions grading. Results A total of 204 patients with solid tumors were included, involving 139 male patients and 65 female patients, with a median age of 65.4 (8.0, 88.4) years. The types of solid tumor were predominantly non-small cell lung cancer (43.1%) , the treatment drugs were mainly sindilizumab (47.1%) , and the treatment patterns were predominantly immunotherapy combined with targeted agents (57.4%) . 12 patients developed ICIs-related endocrinologic adverse reactions, including 9 cases (4.4%) of hypothyroidism (1 case of gradeⅠ, 7 cases of grade Ⅱ, 1 case of grade Ⅲ) with the median onset time of 7 (6, 10) weeks after the treatment of immunological drugs, 1 case (0.5%) of hyperthyroidism (gradeⅠ) occurred 9 weeks after the immunotherapy, 1 case (0.5%) of type 1 diabetes (gradeⅣ) occurred 6 weeks after auto-immunotherapy, 1 case (0.5%) of adrenal dysfunction (gradeⅢ) occurred 7 weeks after immunotherapy. All the 12 patients with endocrinologic adverse reactions were treated in time according to the hierarchical management process, and all their symptoms were improved or returned to normal, and continued to be treated with ICIs. Conclusion The risk of endocrinologic adverse reactions in the endocrine system is relatively high during the use of ICIs, especially abnormal thyroid function, which requires regular detection of endocrine indicators during treatment, timely intervention will not affect the subsequent treatment of ICIs.

Physiologically based pharmacokinetic/toxicokinetic (PBPK/PBTK) models are designed to elucidate the mechanism of chemical compound action in organisms based on the physiological, biochemical, anatomical, and thermodynamic properties of organisms. After nearly a century of research and practice, good results have been achieved in the fields of medicine, environmental science, and ecology. However, there is currently a lack of a more systematic review of progress in the main research directions of PBPK models, especially a more comprehensive understanding of the application in aquatic environmental research. In this review, a total of 3974 articles related to PBPK models from 1996 to 24 March 2024 were collected. Then, the main research areas of the PBPK model were categorized based on the keyword co-occurrence maps and cluster maps obtained by CiteSpace. The results showed that research related to medicine is the main application area of PBPK. Four major research directions included in the medical field were “drug assessment”, “cross-species prediction”, “drug–drug interactions”, and “pediatrics and pregnancy drug development”, in which “drug assessment” accounted for 55% of the total publication volume. In addition, bibliometric analyses indicated a rapid growth trend in the application in the field of environmental research, especially in predicting the residual levels in organisms and revealing the relationship between internal and external exposure. Despite facing the limitation of insufficient species-specific parameters, the PBPK model is still an effective tool for improving the understanding of chemical–biological effectiveness and will provide a theoretical basis for accurately assessing potential risks to ecosystems and human health. The combination with the quantitative structure–activity relationship model, Bayesian method, and machine learning technology are potential solutions to the previous research gaps.

Objectives: The aim of this study was to explore whether indoor or outdoor relative humidity (RH) modulates the influenza epidemic transmission in temperate and subtropical climates. Methods: In this study, the daily temperature and RH in 1558 households from March 2017 to January 2019 in five cities across both temperate and subtropical regions in China were collected. City-level outdoor temperature and RH from 2013 to 2019 were collected from the weather stations. We first estimated the effective reproduction number (Rt) of influenza and then used time-series analyses to explore the relationship between indoor/outdoor RH/absolute humidity and the Rt of influenza. Furthermore, we expanded the measured 1-year indoor temperature and the RH data into 5 years and used the same method to examine the relationship between indoor/outdoor RH and the Rt of influenza. Results: Indoor RH displayed a seasonal pattern, with highs during the summer months and lows during the winter months, whereas outdoor RH fluctuated with no consistent pattern in subtropical regions. The Rt of influenza followed a U-shaped relationship with indoor RH in both temperate and subtropical regions, whereas a U-shaped relationship was not observed between outdoor RH and Rt. In addition, indoor RH may be a better indicator for Rt of influenza than indoor absolute humidity. Conclusion: The findings indicated that indoor RH may be the driver of influenza seasonality in both temperate and subtropical locations in China.

The thermal decomposition process of 1,7-diacetoxy-2,4,6-trinitro-2,4,6-triazaheptane (BSX) was studied by TG-DSC, TG-MS, TG-FTIR technology and ReaxFF molecular dynamics (ReaxFF MD) simulation. The decomposition activation energy of BSX was calculated according to the test results of TG-DSC. The main thermal decomposition products of BSX were determined by combining experiments and simulations, and the possible thermal decomposition pathways were analyzed. The results showed that the decomposition activation energy of BSX is 161 ± 2.6 kJ·mol−1; The thermal decomposition of BSX may generate the main intermediate products C8H14N5O8, C4H7NO2, C2H3O2, HNO2, NO2 and NO, etc., and the intermediate products continued to decompose to generate the final products CH2O, CO2, CO, H2O and N2; The reaction rate constants of each stage of BSX were calculated, and the possible thermal decomposition pathways of BSX were obtained: BSX → C8H14N5O8 + NO2 → C5H9N3O4 + C4H7N4O6 + C4H7NO2 + C3H5N2O4 → C2H3O2 + C2H3O + CH2O + CO2 + CO + H2O + HNO2 + N2O2 + NO2 + NO + H + OH + … → CH2O + CO2 + CO + H2O + N2 + … This study contributes to a deeper understanding of the decomposition process of BSX after heating and has specific significance for reducing the thermal hazard of the BSX pyrolysis process.

Straw return utilizes waste resources to reduce the use of chemical fertilizers worldwide. However, information is still lacking on the relative impact of straw return on soil fertility, the nutrient composition of different soil aggregates, and soil microbial communities. Therefore, this study aimed to understand the effects of different management practices on the crop yield, soil fertility, and soil community composition in a 14-year wheat–rice rotation system. The treatments included a control (without fertilizer and straw addition), chemical fertilization (NPK), straw return without fertilizer (S), and straw addition with chemical fertilizer (NPKS). The results showed that NPKS improved the wheat and rice yield by 185.12% and 88.02%, respectively, compared to the CK treatment. Additionally, compared to the CK treatment, the N, P, and K contents of the wheat stem were increased by 39.02%, 125%, and 20.23% under the NPKS treatment. Compared to the CK treatment, SOM, TN, TP, AN, AP, AK, CEC, AFe, AMn, ACu, and AZn were increased by 49.12%, 32.62%, 35.06%, 22.89%, 129.36%, 48.34%, 13.40%, 133.95%, 58.98%, 18.26% and 33.33% under the NPKS treatment, respectively. Moreover, straw addition promoted the creation and stabilization of macro-aggregates in crop soils. The relative abundance of macro-aggregates (0.25–2 mm) increased from 37.49% to 52.97%. Straw addition was associated with a higher proportion of aromatic and carbonyl carbon groups in the soil, which, in turn, promoted the formation of macro-aggregates. Redundancy analysis showed that straw return significantly increased the microbial community diversity. These findings demonstrate that straw addition together with chemical fertilizer could increase the crop yield by improving soil fertility, soil aggregate stability, and the diversity of fungi.

Ultrasonic contactless power transfer (UCPT) technology is a new kind of contactless power transfer (CPT) technology, which can be used to transfer power to loads in enclosed metal containers. In this paper, an UCPT system of transferring power and data simultaneously of different direction using only one pair of transducer is proposed. In the proposed system, power is transferred from the transmitting side to receiving side, and data is transferred in reverse direction simultaneously, from receiving side to transmitting side. The proposed system consists of power transfer channel and data backward transfer channel. The power transfer channel is modeled and the data backward transfer channel is analyzed in detail. 2ASK technology is used in data transfer channel. To show the effectiveness of the proposed system, an experimental setup is built. For power transfer channel, the output power is up to 40 W, and for data transfer channel, the data transfer rate is up to 1.6 kbps in ideal situation. When transferring a picture, the data transfer rate is 1.43 kbps and the output voltage is 5V which are realized at the same time.

As the concentration of fine particles (PM _2.5 ) is declining, ozone (O _3 ) concentration has been increasing in China in recent years. To collaboratively control PM _2.5 and O _3 , it is critical to understand the relationship between the two and identify major controlling factors. We use a convergent cross-mapping method to detect the causal relationship between daily PM _2.5 and maximum daily 8 h average (MDA8) O _3 concentrations in Beijing, Taizhou, Shenzhen and Chengdu, China, in the four seasons in 2015–2021. In addition, we also examined causal effects of atmospheric oxidation capacity, precursors and meteorological elements on PM _2.5 and MDA8 O _3 in the four cities. PM _2.5 and MDA8 O _3 are strongly positively correlated and show bidirectional causal relationships during the Beijing and Taizhou summer and in the four seasons in Shenzhen, due mainly to the strong photochemical reactions in the daytime. During the Beijing winter, PM _2.5 and MDA8 O _3 show bidirectional causal relationships, but the two are significantly negatively correlated, driven by NO _2 and relative humidity. Weak bidirectional, unidirectional and no causal effects between PM _2.5 and MDA8 O _3 are detected in other seasons in the four cities. In these seasons and cities, the top three causal factors of PM _2.5 differ from those of MDA8 O _3 . Season-, city- and pollutant-specific control measures of PM _2.5 and MDA8 O _3 are required.

Abstract Background School closure is a common mitigation strategy during severe influenza epidemics and pandemics. However, the effectiveness of this strategy remains controversial. In this study, we aimed to explore the effectiveness of school closure on seasonal influenza epidemics in provincial-level administrative divisions (PLADs) with varying urbanization rates in China. Methods This study analyzed influenza surveillance data between 2010 and 2019 provided by the Chinese National Influenza Center. Taking into consideration the climate, this study included a region with 3 adjacent PLADs in Northern China and another region with 4 adjacent PLADs in Southern China. The effect of school closure on influenza transmission was evaluated by the reduction of the effective reproductive number of seasonal influenza during school winter breaks compared with that before school winter breaks. An age-structured Susceptible-Infected-Recovered-Susceptible (SIRS) model was built to model influenza transmission in different levels of urbanization. Parameters were determined using the surveillance data via robust Bayesian method. Results Between 2010 and 2019, in the less urbanized provinces: Hebei, Zhejiang, Jiangsu and Anhui, during school winter breaks, the effective reproductive number of seasonal influenza epidemics reduced 14.6% [95% confidential interval (CI): 6.2–22.9%], 9.6% (95% CI: 2.5–16.6%), 7.3% (95% CI: 0.1–14.4%) and 8.2% (95% CI: 1.1–15.3%) respectively. However, in the highly urbanized cities: Beijing, Tianjin and Shanghai, it reduced only 5.2% (95% CI: -0.7–11.2%), 4.1% (95% CI: -0.9–9.1%) and 3.9% (95% CI: -1.6–9.4%) respectively. In China, urbanization is associated with decreased proportion of children and increased social contact. According to the SIRS model, both factors could reduce the impact of school closure on seasonal influenza epidemics, and the proportion of children in the population is thought to be the dominant influencing factor. Conclusions Effectiveness of school closure on the epidemics varies with the age structure in the population and social contact patterns. School closure should be recommended in the low urbanized regions in China in the influenza seasons. Graphical abstract

Polycyclic aromatic hydrocarbons (PAHs) are an important class of pollutants in China. The land use regression (LUR) model has been used to predict the selected PAH concentrations and screen the key influencing factors. However, most previous studies have focused on particle-associated PAHs, and research on gaseous PAHs was limited. This study measured representative PAHs in both gaseous phases and particle-associated during the windy, non-heating and heating seasons from 25 sampling sites in different areas of Taiyuan City. We established separate prediction models of 15 PAHs. Acenaphthene (Ace), Fluorene (Flo), and benzo [g,h,i] perylene (BghiP) were selected to analyze the relationship between PAH concentration and influencing factors. The stability and accuracy of the LUR models were quantitatively evaluated using leave-one-out cross-validation. We found that Ace and Flo models show good performance in the gaseous phase (Ace: adj. R2 = 0.14–0.82; Flo: adj. R2 = 0.21–0.85), and the model performance of BghiP is better in the particle phase (adj. R2 = 0.20–0.42). Additionally, better model performance was observed in the heating season (adj R2 = 0.68–0.83) than in the non-heating (adj R2 = 0.23–0.76) and windy seasons (adj R2 = 0.37–0.59). Those gaseous PAHs were highly affected by traffic emissions, elevation, and latitude, whereas BghiP was affected by point sources. This study reveals the strong seasonal and phase dependence of PAH concentrations. Building separate LUR models in different phases and seasons improves the prediction accuracy of PAHs.

Background: Ambient and household air pollution are found to lead to premature deaths from all-cause or cause-specific death. The national lockdown measures in China during COVID-19 were found to lead to abrupt changes in ambient surface air quality, but indoor air quality changes were neglected. In this study, we aim to investigate the impacts of lockdown measures on both ambient and household air pollution as well as the short-term health effects of air pollution changes. Methods: In this study, an up-to-date emission inventory from January to March 2020 in China was developed based on air quality observations in combination with emission-concentration response functions derived from chemical transport modeling. These emission inventories, together with the emissions data from 2017 to 2019, were fed into the state-of-the-art regional chemistry transport model to simulate the air quality in the North China Plain. A hypothetical scenario assuming no lockdown effects in 2020 was also performed to determine the effects of the lockdown on air quality in 2020. A difference-to-difference approach was adopted to isolate the effects on air quality due to meteorological conditions and long-term decreasing emission trends by comparing the PM2.5 changes during lockdown to those before lockdown in 2020 and in previous years (2017–2019). The short-term premature mortality changes from both ambient and household PM2.5 changes were quantified based on two recent epidemiological studies, with uncertainty of urban and rural population migration considerations. Findings: The national lockdown measures during COVID-19 led to a reduction of 5.1 µg m−3 in ambient PM2.5 across the North China Plain (NCP) from January 25th to March 5th compared with the hypothetical simulation with no lockdown measures. However, a difference-to-difference method showed that the daily domain average PM2.5 in the NCP decreased by 9.7 µg m−3 between lockdown periods before lockdown in 2020, while it decreased by 7.9 µg m−3 during the same periods for the previous three-year average from 2017 to 2019, demonstrating that lockdown measures may only have caused a 1.8 µg m−3 decrease in the NCP. We then found that the integrated population-weighted PM2.5, including both ambient and indoor PM2.5 exposure, increased by 5.1 µg m−3 during the lockdown periods compared to the hypothetical scenario, leading to additional premature deaths of 609 (95% CI: 415–775) to 2,860 (95% CI: 1,436–4,273) in the short term, depending on the relative risk chosen from the epidemiological studies. Interpretation: Our study indicates that lockdown measures in China led to abrupt reductions in ambient PM2.5 concentration but also led to significant increases in indoor PM2.5 exposure due to confined indoor activities and increased usages of household fuel for cooking and heating. We estimated that hundreds of premature deaths were added as a combination of decreased ambient PM2.5 and increased household PM2.5. Our findings suggest that the reduction in ambient PM2.5 was negated by increased exposure to household air pollution, resulting in an overall increase in integrated population weighted exposure. Although lockdown measures were instrumental in reducing the exposure to pollution concentration in cities, rural areas bore the brunt, mainly due to the use of dirty solid fuels, increased population density due to the large-scale migration of people from urban to rural areas during the Chinese New Year and long exposure time to HAP due to restrictions in outdoor movement.

As a critical air pollutant, PM2.5 is proved to be associated with numerous adverse health impacts and pose serious challenges to human life. This situation is especially important for China as the most populous and one of the heaviest PM2.5 polluted country in the world. However, health burden estimations reported for China in previous studies may be biased due to the usage of PM2.5 concentrations at a coarsely spatial resolution, as well as the ignorance of the spatial discrepancies of parameters (e.g. respiratory rate) employed in the exposure-response function. This study therefore utilized a hybrid remote sensing-geostatistical approach to refine PM2.5 concentrations at 1 km resolution across mainland China from 2013 to 2017. Meanwhile, nationwide exposure parameters were for the first time introduced to weight the integrated exposure response (IER) function to calculate and spatially reallocate the corresponding PM2.5-attributable premature deaths at 1 km resolution. Results showed that annually averaged PM2.5 concentrations in mainland China decreased by 39.5%, from 59.1 μg/m3 in 2013 to 35.8 μg/m3 in 2017. Subsequently, PM2.5 attributable premature deaths reduced 12.6%, from 1.20 million (95% CI: 0.57; 1.71) in 2013 to 1.05 million (95% CI: 0.44; 1.44) in 2017. This declining trend was found in most parts of China except some areas in Xinjiang, Jilin, and Heilongjiang provinces. As a result, 214,821 (95% CI: 96,675; 302,897) life were saved with an estimated monetary value of US$ 210.14 billion (2011 values). However, it has to be acknowledged that, the central and northern China within priority areas of air pollution control were still experiencing high numbers of premature deaths due to the severe PM2.5 pollution and high-density population. But more worrying than these priority areas are those Harbin-Changchun Metropolitan Region, City Belt in Central Henan and Yangtze-Huaihe City Belt in non-priority areas, which also have been seriously suffering PM2.5 attributable premature deaths over 28, 000 cases per year. In conclusion, despite the huge gain in life-saving effects in China over the past five years with the help of air pollution intervention policy, future work on cleaner air and better human health is still strongly needed, especially in non-priority areas of air pollution control. Keywords: PM2.5, Health burden, Spatial-temporal, Remote sensing, Exposure parameters

Background: Childhood obesity is a global health issue, and limited evidence suggests that air pollution may be a contributing factor. This study aims to examine whether exposure to fine particulate matter (PM2.5) is associated with obesity status in a nationally representative sample of schoolchildren in China. Methods: The study population consisted of 41,439 schoolchildren of 6–17 years old, recruited from 30 provinces in China using a multi-stage stratified sampling method. Weights and heights were measured for all the participants, and sociodemographic information was collected using a questionnaire. The obesity status was classified following the Chinese national standards. The PM2.5 exposure was estimated as the 5-year average concentration at the school location for each participant. The association between obesity status and PM2.5 exposure was examined using weighted logistic regressions adjusted for potential confounders. Results: The prevalence of normal weight, overweight, and obesity were 78.5%, 12.4%, and 9.0%, respectively. PM2.5 exposure averaged 59.8 ± 17.6 μg/m3 with a range of 30.5–115.2 μg/m3 among all the participants. The risk of obesity increased by 10.0% (95% confidence interval: 3.0–16.0%) per 10 μg/m3 increase in PM2.5 exposure. The PM2.5-associated risk was significantly elevated in older age groups and children living in urban areas (interaction p-values

China has made great efforts towards air pollutant concentration control during the past five years, which has led to positive outcomes. However, air pollutant concentration focused efforts were considered separately from human exposure risk. And this might result in a misunderstanding that reducing exposure risk can only rely on the national level measures of air pollutant control. This study integrates the first Chinese survey of human activity patterns and the spatially continuous high-resolution PM2.5 concentration maps to reveal the spatial and temporal variations of China’s air pollution exposure risk from 2013 to 2017. More importantly, the effects on risk reduction from multi-scale and multi-object perspectives (reductions of ambient PM2.5 concentrations by national or provincial measures and changes of individual behavior patterns by personal efforts) are deeply investigated. Results show that the reductions of PM2.5 concentration and associated reductions of exposure risk from 2013 to 2017 were 40% and 35.7%, respectively. They also showed that both the reduction of PM2.5 concentrations and change of personal behavior patterns were effective for risk reduction when China’s total PM2.5 exposure risk was higher than 1.58. However, only individual behavior changes contributed to risk reduction for scenarios with state-level risk value below 1.58. For regional strategies, threshold values for PM2.5 exposure risk control differentiating national measures or personal efforts were spatially and temporally dependent. The role of personal behavior changes on PM2.5 exposure risk reduction was growing in these five years with concentration rapidly decreasing regions. The findings suggest that people-centered air pollution exposure risk prevention not only depends on government management for air pollution control, but also on individual changes of activity patterns. Efforts from the state and individuals are both essential for reducing air pollution exposure risk in China, especially growing individual efforts are needed in regions with the decreasing air pollutant concentrations in the coming future. Moreover, this study mainly discussed the PM2.5 exposure risk from the macroscopic perspective, the research at the microcosmic perspective is also needed in the further study. Keywords: Air pollution, Exposure risk, Individual exposure, Exposure factors

Abstract Silicon nanowires (SiNWs) with excellent light trapping properties have been widely applied in photovoltaic devices, which provide opportunities for boosting the photons harvested by Si. However, the photoexcited carriers are easily trapped and recombined by high-density surface defects due to higher surface area prolonging to depth of nanowire. In this work, in order to reduce the surface defects and recombination rate of SiNWs, a simple solution process is used to modify the surface structure. Applying the tetramethyl ammonium hydroxide (TMAH) treatment leads to smooth and taper Si NW surface, which improves the open-circuit voltage (V oc) and fill factor (FF) obviously. Thus, a champion PCE of 14.08% is achieved for the nanostructured Si/PEDOT:PSS hybrid device by 60-s TMAH treatment. It also indicates that TMAH treatment promises a simple and effective method for enhancing Si NW-based devices.

Abstract Rapid urbanization is causing serious PM2.5 (particulate matter ≤2.5 μm) pollution in China. However, the impacts of human activities (including industrial production, energy production, agriculture, and transportation) on PM2.5 concentrations have not been thoroughly studied. In this study, we obtained a regression formula for PM2.5 concentration based on more than 1 million PM2.5 recorded values and data from meteorology, industrial production, energy production, agriculture, and transportation for 31 provinces of mainland China between January 2013 and May 2017. We used stepwise regression to process 49 factors that influence PM2.5 concentration, and obtained the 10 primary influencing factors. Data of PM2.5 concentration and 10 factors from June to December, 2017 was used to verify the robustness of the model. Excluding meteorological factors, production of natural gas, industrial boilers, and ore production have the highest association with PM2.5 concentration, while nuclear power generation is the most positive factor in decreasing PM2.5 concentration. Tianjin, Beijing, and Hebei provinces are the most vulnerable to high PM2.5 concentrations caused by industrial production, energy production, agriculture, and transportation (IEAT).

World Health Organization updated the target of annual mean NO _2 from 40 μ g m ^−3 to 10 μ g m ^−3 in 2021 based on new evidences that showed statistically independent effects of long-term exposure to ambient NO _2 and mortality. We estimate the excess deaths associated with long-term exposure to ambient NO _2 (DAAN) from non-accidental disease (NAD), cardiovascular disease (CVD) and respiratory disease (RD) in China in 2013–2020 using a counterfactual analytic framework adopted by Global Burden Disease. We use relative risk (RR) values based on a meta-analysis, and assume a linear concentration-response (C-R) function and a threshold value of 10 μ g m ^−3 . DAAN from NAD vary in 279 (95% Cl: 189–366) to 339 (95% Cl: 231–442) thousand in 2013–2020, comparable to excess deaths attributed to long-term exposure to ambient O _3 in China. DAAN from NAD changes by −43%–+220% using different RR values, C-R function shapes, and threshold values. DAAN from RD reduces while those from CVD increases significantly in 2013–2020. DAAN from RD account for ∼10% of total DAAN. We found that the reduction of NO _2 concentration and baseline mortality of NAD offsets the adverse effects of population growth and aging in 2013–2017. In 2017–2020, the contribution from air pollution reduction surpasses the adverse effects of population growth and aging in most regions. We suggest that continuing the reduction rate of NO _2 emissions in 2013–2020 would offset the effects of population growth and aging in 2020–2030. Faster reduction of NO _2 sources is required to reduce DAAN in Liaoning, Shanxi, Shanghai, and Anhui, where DAAN from NAD, CVD and RD increased in 2013–2020. Our results should be interpreted with caution because the causality support of long-term exposure to ambient NO _2 on mortality from toxicological studies is not firm yet, and NO _2 is possibly just a marker of traffic-related pollutants.

Abstract Traditional sampling for soil pollution evaluation is cost intensive and has limited representativeness. Therefore, developing methods that can accurately and rapidly identify at-risk areas and the contributing pollutants is imperative for soil remediation. In this study, we propose an innovative integrated H-G scheme combining human health risk assessment and geographical detector methods that was based on geographical information system technology and validated its feasibility in a renewable resource industrial park in mainland China. With a discrete site investigation of cadmium (Cd), arsenic (As), copper (Cu), mercury (Hg) and zinc (Zn) concentrations, the continuous surfaces of carcinogenic risk and non-carcinogenic risk caused by these heavy metals were estimated and mapped. Source apportionment analysis using geographical detector methods further revealed that these risks were primarily attributed to As, according to the power of the determinant and its associated synergic actions with other heavy metals. Concentrations of critical As and Cd, and the associated exposed CRs are closed to the safe thresholds after remediating the risk areas identified by the integrated H-G scheme. Therefore, the integrated H-G scheme provides an effective approach to support decision-making for regional contaminated soil remediation at fine spatial resolution with limited sampling data over a large geographical extent.

Feruloyl esterase (FAE; EC 3.1.1.73) catalyzes the hydrolysis of the 4-hydroxy-3-methoxycinnamoyl group in an esterified sugar to assist in waste biomass degradation or to release ferulic acid (FA). An FAE-producing strain was isolated from humus soil samples and identified as Bacillus pumilus SK52.001. The BpFAE gene from B. pumilus SK52.001 was speculated and heterogeneously expressed in Bacillus subtilis WB800 for the first time. The enzyme exists as a monomer with 303 amino acids and a molecular mass of 33.6 kDa. Its specific activity was 377.9 ± 10.3 U/(mg protein), using methyl ferulate as a substrate. It displays an optimal alkaline pH of 9.0, an optimal temperature of 50 °C, and half-lives of 1434, 327, 235, and 68 min at 50, 55, 60, and 65 °C, respectively. Moreover, the purified BpFAE released 4.98% FA of the alkali-acidic extractable FA from de-starched wheat bran (DSWB). When the DSWB was enzymatically degraded by the synergistic effect of the BpFAE and commercial xylanase, the FA amount reached 49.47%. It suggested that the alkaline BpFAE from B. pumilus SK52.001, which was heterologously expressed in B. subtilis WB800, possesses great potential for biomass degradation and achieving high-added value FA production from food by-products.

Time-of-Use (TOU) tariff is one of effective price-based demand response strategy, which can guide consumers to relieve the load peak pressure of power system and tap demand-side response potential. However, without considering the impact of pricing, improper peak-valley time period schemes may lead to a decrease in power supply reliability and an increase in operation costs of the power system. Therefore, this paper presents a peak-valley time period partition scheme of TOU tariff based on fuzzy equivalence relation clustering (FERC) algorithm. First, the solving steps and corresponding mathematical models of FERC algorithm are given, such as the characteristic indicator fuzzy set determined by the membership function and the fuzzy equivalence matrix. Secondly, the peak-valley characteristics of the load are first analyzed, and then a peak-valley period partition clustering based on FERC algorithm is proposed by combining semi-trapezoid membership functions and partition criterion constraints. Finally, the effectiveness of the proposed method is verified under a typical daily load in Hunan province. The results show that the proposed method can not only accurately reflect the peak valley characteristics of the load curve, but also effectively improve the calculation speed and convergence of peak-valley time period partition. [ABSTRACT FROM AUTHOR]

A cleaning model based on clustering by fast search and find of density peaks (CFSSFDP) is proposed to address the problem of many data types and low data quality in the distribution network fault database. First, auto-extraction model of fault data features based on 1D convolutional auto-encoder is established to obtain fault features of massive fault data. Next, the fault data features are clustered by CFSSFDP, the incorrect and invalid fault features are isolated, and the incorrect and invalid fault data in the database are cleaned. Finally, the effectiveness and accuracy of the model for cleaning of fault data in distribution network is verified through the experimental analysis of the cleaning of Simulink simulation fault data. [ABSTRACT FROM AUTHOR]

Cable channel fire is an important factor affecting the safe operation and maintenance of power cables. This paper summarizes the current research situation of fire-extinguishing technology, analyzes the fire-extinguishing technology suitable for cable channel, and proposes to use S-type aerosol fire-extinguishing technology to extinguish the fire of cable channel..

A semantic segmentation method based on the fully convolutional network is proposed to detect the buffer layer defect in high voltage cable automatically. One hundred seventy-seven high-resolution X-ray images of cables are collected. FCN-8s and VGG16 backbone are adopted. The results indicated that the FCN-8s achieves the mIoU to 0.67 on the test set, proving to be an efficient way to detect the buffer layer defects.

This study focuses on assessing the health risk by particulate matter (PM) inhalation within the Abuja municipal area, Nigeria. Particulate matters (PM2.5 and PM10), HCHO and VOCs were collected by A handheld portable smart air quality detector BR-SMART-126. A hybrid single-particle Lagrangian integrated trajectory (HYSPLIT) model for backward trajectory was applied to tract the air flow (transportation) and potential sources. Health risk was estimated by comparing with the air quality index (AQI) stipulated by the World Health Organization (WHO). The result shows that the daily averaged concentrations of PM2.5 varied from 15.30 µg/m3 to 70.20 µg/m3. The top four most-polluted locations (Locations 10, 14, 17 and 18) of the twenty locations were found to be above the acceptable (25 µg/m3) AQI limit stipulated by WHO, which all fell far under the unhealthy AQI value index level. In general, business/commercial locations had the highest PM2.5 level followed by transport/market, offices/mixed use and residential. The results from the backwards trajectories show that the source of local particles for the four most-polluted locations is long-range air transport originating from the Atlantic Ocean. The results of the health-risk assessment implies that for PM2.5, the AQI varied from 73.2 to 280.8 in this assessment. Based on this, the population of workers within the business location are at health risk based on the relatively poor air quality in these areas—especially location 10 and 17. Based on these findings, it is recommended that the regulatory and enforcement agency needs to develop a more robust monitoring mechanism, regulations and enforcement. Furthermore, there is need for a national drive on renewable energy, clean energy for business/commercial district to help reduce fumes from generators and to form cleaner air initiatives in order to ensure a safe environment to live in as well as reduce particulate matters in the city.