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Daqingshan piedmont fault is located in the northern margin of Hetao basin and has been active strongly since the Late Quaternary. Previous researchers had conducted extensive research on the characteristics of paleoseismic in this area, but limited by the dating techniques and the fact that there were fewer data available on the same fault profile that can effectively constrain paleoseismic events, and fewer profiles that can reveal more paleoseismic events. This paper explores the excavation of an paleoseismic trench on the east side of Lianhuashan in the western section of Tuyouqi of the Daqingshan piedmont fault, using Optically Stimulated Luminescence data, and combineing with the age data of previous exploration trenches. By using the fault successive limit method, it is found that the western section of the Tuyouqi fault has experienced five paleoseismic events approximately 11500 years ago, with an average recurrence interval of 2260 years. The five paleoseismic events in this section of the fault, from new to old, are 1.28 to 1.42 ka, 3.41 to 3.60 ka, 4.08 to 5.01 ka, 8.26 to 9.32 ka, and 10.70 to 11.30 ka, respectively. The latest event of activity should be the earthquake of 849 AD. Meanwhile, the trench exploration revealed that the fault in this section exhibits a normal fault nature, with an inclination angle between 58 and 77 degrees. According to empirical formula, the potential seismic capacity of the Baotou section, the western section of Tuyouqi, and the western section of Tuzuoqi are around MW6.8～7.1, MW6.8～7.1 and MW7.1～7.2, respectively. The magnitude obtained by the empirical formula in this paper is relatively small, and there may be cascade rupture. In the later stage, it is necessary to conduct a comprehensive evaluation of the risk of the western section of Daqingshan piedmont fault combined with other means.

Pepper originated in South America and was introduced to China in the 16th century. With high nutritional value, pepper has an important role in health care, beauty, food, medicine, violence and other industries. It becomes one of the most important vegetable crops in China. With the gradual increase of cultivation area pepper ranks the top among vegetable crops in China in this aspect. In the process of pepper production, it inevitably suffers from various diseases, causing great losses to production. It is the most economical and effective measure to control diseases through selecting disease-resistant varieties, although the chemical control methods and agricultural control measures can reduce the harm to a certain extent. With the development of molecular biology, the combination of molecular breeding and conventional breeding methods for disease resistance is a direction of future breakthroughs. In recent years, great progress has been made in the molecular breeding of pepper disease resistance, especially, the molecular mechanism of disease resistance. Molecular breeding mainly includes two parts: one is marker-assisted breeding, and the other is creating disease-resistant breeding materials by means of genetic engineering. In marker-assisted breeding, molecular markers must be found first. Molecular markers are divided into gene markers, markers obtained by linkage analysis in segregation populations, and markers gotten by association analysis through sequencing of a large number of materials. The premise of genetic engineering is to isolate and obtain disease resistance genes, and then introduce them into pepper breeding materials with good economic traits, or mutate negatively regulated genes through gene editing technology or gene silencing technology to improve disease resistance of plants. In this paper, molecular markers and marker-assisted selection, molecular mechanism of disease resistance and disease-resistant germplasm (resistance to virus, bacterial wilt and Phytophthora capsici) obtained by genetic engineering technology are comprehensively introduced, and the development trend and research focus in the future are prospected.

ObjectiveTo comprehensively assess rural environmental sanitation of 25 prefectures/counties/districts in and outside the Yellow River Basin, Shandong province for developing strategies on improvement of rural environmental sanitation. MethodsWe collected monitoring data of 2021 on rural environment sanitation of 25 prefectures/counties/districts of Shandong province; the 13 regions located at the Yellow River Basin were set as cases and the 12 regions outside the basin as controls. Principal component analysis and technique for order preference by similarity to an ideal solution (TOPSIS) analysis was adopted in the assessment. Nine positive high performance indicators were introduced to fit the evaluation model. Regional-specific standardized distance between the scores of each of the nine indicators and optimal ideal solution was utilized to evaluate rural environment sanitation of the 25 prefectures/counties/districts and comprehensive evaluation index was calculated for each of the 25 regions using Euclidean distance approximation method to determine ideal points through TOPSIS. ResultsThe nine core indicators included in the principal component analysis were region-specific annual net income per capita for farmers, annual net income per capital for all rural residents, county-level investment in rural environmental health, construction rate of comprehensive improvement projects for rural sanitation, construction rate of environment sanitation management system, prevalence of sanitary toilet, coverage of centralized rural water supply, transfer ratio of solid waste in rural areas, and transfer ratio of domestic sewage in rural areas. The three identified principal components for rural environment sanitation evaluation were economic condition, sanitation management, and primary health facilities, with the eigenvalues of 2.109, 2.076, and 1.349 and a cumulative contribution rate of 61.485%. Among the top five prefectures/counties/districts with higher values of comprehensive evaluation index, two were located in the Yellow River Basin (Huantai county and Shouguang prefecture, with the scores of 0.705 and 0.665) and three were outside of the basin (Rongcheng, Yanzhou and Gaomi prefectures, with the scores of 0.758, 0.687, and 0.662, respectively). Among the three identified principal components, the score for economic conditions showed the highest coefficient of variation (CV, 0.481) for the regions in the Yellow River Basin; while, the score for rural environmental sanitation management showed the lowest CV (0.114). ConclusionIn rural Shandong, the sanitation management and primary health facilities are better in the regions in the Yellow River Basin but the contribution of the economic situation to the comprehensive index for environment sanitation evaluation is relatively low compared to those in the regions outside of the basin.

BackgroundA number of studies have shown that heavy metals in atmospheric PM2.5 have impacts on human health, while studies on the impact of long-term and low-concentration exposure to lead in PM2.5 on human health are limited. ObjectiveTo investigate the pollution characteristics of lead in ambient PM2.5 and assess its chronic health risks. MethodsDaily PM2.5 concentration data in Jinan from 2014 to 2019 were collected, and the year-by-year trend of PM2.5 concentration was analyzed. Licheng District (an industrial area) and Shizhong District (a residential area) were elected to install an ambient PM2.5 monitoring stationrespectively. The sampling instrument was a 100 L·min−1 high-flow PM2.5 sampler, with a cumulative sampling time of 20-24 h per day, using a quartz fiber filter membrane for lead detection and a glass fiber filter membrane for PM2.5 determination. The sampling frequency was 7 consecutive days per month from the 10th to the 16th (A total of 493 d were sampled and some were missing; 172 d during the heating period and 321 d during the non-heating period). Two PM2.5 samples were collected in one monitoring site each day. A total of 986 samples were collected in one monitoring site. The lead content in PM2.5 samples was detected by inductively coupled plasma mass spectrometry. The concentration of PM2.5 was measured by weighing method. The annual average concentration and enrichment factor of lead in PM2.5, the change trend of lead content per unit mass of PM2.5, and the difference between heating period and non-heating period from 2014 to 2019 were estimated. Technical guide for environment health risk assessment of chemical exposure (WS/T 777-2021) was used to assess the health risks of exposure to lead in PM2.5. ResultsThe average annual concentration of lead in PM2.5 ranged from 23.2 ng·m−3 to 154.7 ng·m−3. The average concentration in heating period from 2015 to 2019 was higher than that in non-heating period, and the differences in 2015, 2017, and 2019 were statistically significant (P < 0.01 or 0.001). The enrichment factors ranged from 200 to 1342 in 2014 to 2019. The average enrichment factors in heating period in 2015, 2017, and 2018 was higher than those in non-heating period, and the difference was statistically significant (P < 0.05 or 0.001). The lead contents per unit mass of PM2.5 ranged from 493 ng·mg−1 to 1944 ng·mg−1, and the differences between heating period and non-heating period in 2014, 2017, and 2018 were statistically significant (P < 0.05 or 0.001). The average annual concentration and enrichment factor of lead in PM2.5 showed a downward trend, and thus the lead content per unit mass of PM2.5 also decreased. From 2014 to 2019, the carcinogenic risk of lead in PM2.5 in Jinan ranged from 1.69×10−8 to 2.45×10−6, showing a significant downward trend year by year, and the 95th percentile decreased by 3%-46% from the previous year. The carcinogenic risk level of lead was reduced to an acceptable level (

BackgroundThe presence of formaldehyde, ammonia, benzene, toluene, and xylene in indoor air of public places has been confirmed to cause health damage. The employees of barber and beauty shops are exposed to relatively enclosed space for a long time, and could surfer more serious health risks from indoor air chemical pollutants.ObjectiveTo analyze the concentrations of common indoor air chemical pollutants in barber shops and beauty salons in Liaocheng City, and explore potential health risks of the pollutants for employees.MethodsUsing a stratified randomized sampling method, 8 to 10 barber shops and 5 to 10 beauty salons were selected in the main urban area of Liaocheng City to conduct monitoring of the sanitary conditions of public places in winter and summer every year from 2016 to 2021; the indoor air concentrations of formaldehyde, ammonia, benzene, toluene, and xylene in the selected sites were measured, and a questionnaire survey was conducted to collect exposure characteristics of indoor pollutants. The concentration distributions of the five chemical pollutants were obtained from the monitoring data for 6 consecutive years, and the health risk assessment model recommended by the U.S. Environmental Protection Agency was used to perform health risk assessment of inhalation exposure.ResultsIn 2016–2021, the median indoor air concentrations of formaldehyde, ammonia, benzene, toluene, and xylene in the two types of sites were lower than the limits of Hygienic Indicators and Limits for Public Places (GB 37488-2019), but the concentrations of some monitoring sites were higher than the limits. The disqualification rates of the five pollutants in the barber shops were 16.8%, 2.7%, 2.4%, 6.4%, and 12.0%, respectively. The disqualification rate of formaldehyde was the highest in all pollutants (22.0%), while the disqualification rates of ammonia, toluene, and xylene were 1.3%, 2.0%, and 2.0% in beauty salons respectively. Both formaldehyde and benzene were found to have carcinogenic risks (CR) in the two types of public places. Both median values of CR were greater than 1.0×10−6, and both maximum values were greater than 1.0×10−4. Formaldehyde had the highest non-carcinogenic risk in the indoor air of barber shops and beauty salons. The median non-carcinogenic hazard quotients (HQ) of formaldehyde were both greater than 1, and the maximum values were 16.72 and 12.19 times of the standard value; ammonia and toluene had the lowest non-carcinogenic risks, and their maximum values of HQ were less than 1; the median HQs of benzene and xylene were far less than 1, but their maximum risk values of barber shop were greater than 1.ConclusionFor the sake of worker's health, formaldehyde and benzene should be the indoor air pollutant control priority for barber shops and beauty salons in Liaocheng; formaldehyde poses the most serious health hazard to practitioners and should be given high attention and necessary measures to reduce the hazard; benzene poses certain carcinogenic risks, with some of its highest values exceeding 10−4, which is higher than the recommended safety threshold.

In order to analyze the influence of key parameters on the contact and lubrication performance of the inner meshing worm gear of the roller envelop， the mathematical model of the new worm drive is built. And the lubrication angle and the induced normal curvature equation are constructed by the meshing equation. Then the influence of the key parameters on the lubrication and contact performance of worm drive are analyzed by the numerical calculation method. These key parameters include the center distance，the transmission ratio，roller radius and the worm-wheel rotational deflection. The analysis shows that in these key parameters，the deflection angle of the worm wheel has a great influence on the contact and lubrication performance of the inner meshing worm gearing of the roller envelope. It is suggested that the deviation angle of the worm wheel is the best in the range of 0°to 40°. And the corresponding parameters are selected for 3D modeling analysis to verify the validity of the analysis parameters. The study provides a reference for further research on the roller enveloping internal worm drive.

Background People with normal weight obesity (NWO) are prone to cardiovascular diseases in their middle and old age. High-intensity interval training (HIIT) has been demonstrated to effectively improve cardiovascular health. However, whether HIIT can decrease the risk of cardiovascular diseases in NWO population is not clear. Objective To explore the effects of HIIT on the advanced glycation end-products (AGEs) and the risk of cardiovascular disease in NWO female university students. Methods From November to December 2020, 137 female college students were recruited in Shanghai University of Medicine & Health Sciences, among whom 40 NWO cases were screened out as subjects by the Asian female NWO standard. They were equally and randomly divided into a control group (n=20) and a HIIT intervention group (n=20) to receive no interventions or weekly five-day interventions, for consecutive four weeks after one-week adaptive training. Body weight, body mass index (BMI) , body fat percentage (BF%) , visceral fat level (VFL) , visceral fat area (VFA) , waist circumference, levels of four blood lipids 〔high-density lipoprotein (HDL) , low-density lipoprotein (LDL) , triglyceride (TG) , and total cholesterol (TC) 〕, cardiovascular disease risk (assessed by the China-PAR model) , AGEs, and fasting blood glucose of two groups were observed before and after intervention. The correlation between AGEs and cardiovascular disease risk was analyzed. Results Except for 10 dropouts, the remaining 30 cases (13 in the control group and 17 in the HIIT intervention group) were finally included for analysis. After intervention, the average BMI, BF%, VFA, VFL, waist circumference, TC/HDL ratio, LDL/HDL ratio, TG/HDL ratio, AGEs and fasting blood glucose in HIIT intervention group were lower than those in control group (P