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ObjectiveTo assess the exposure and health risks from perchlorates in food and tea among Chinese residents grouped by key and common areas.MethodsPerchlorate content data for food and tea in China were collected from the literature. Combined with data from the Chinese Total Diet Study in 2015 and using the hazard quotient， the estimated dietary exposure to perchlorate in different areas was assessed and compared using several health-based guidance values.ResultsThe highest mean perchlorate content was 175.54 μg/kg in tea. The results of the probability assessment showed that vegetables were critical exposure pathways in the Chinese population， accounting for 79.40% of total daily perchlorate intake. The 99% daily perchlorate intake of Chinese populations was lower than the provisional maximum tolerable daily intake （PMTDI， 10 μg/kg∙BW） set by the Joint FAO/WHO. However， the daily perchlorate intake of 4.96% and 26.57% of the residents in two areas far exceeded the temporary tolerable daily intake （tTDI， 0.7 μg/kg∙BW） set by China. In tea， 95% of daily perchlorate intake was lower than the PMTDI， but the daily perchlorate intakes of 57.47% and 77.94% of the tea drinkers in the two areas exceeded the tTDI.ConclusionThe risk of exposure to perchlorate via dietary intake in the Chinese population is generally low； however， there are key areas where the exposure is significantly higher than those in other areas owing to high local pollution.

ObjectiveTo analyze the co-occurrence characteristics of mycotoxins in wheat， a classification model based on climatic regions of China was built.MethodsA total of 887 wheat samples collected from 12 provinces/autonomous regions were analyzed for the concentrations of eight mycotoxins， including deoxynivalenol， nivalenol， aflatoxins， ochratoxin A， fumonisins， zearalenone， T-2 and HT-2. All the samples were divided into three groups， temperate continental climate， temperate monsoon climate and subtropical monsoon climate， according to the climate types of their sampling sites. The borderline-SMOTE method was used for sample augment to balance the data set. Principal component analysis （PCA） was applied for data dimension reduction， and the first two dimensions with a cumulative contribution rate of 97% were chosen as the characteristics of the original data. The classification of the data feature was implemented using the k-nearest neighbor （KNN） nonlinear classifier， and the parameters of the KNN model were optimized using GridSearchCV. Confusion Matrix， accuracy， recall rate and F1 score were used as the indexes for model evaluation， and the performance of this model was compared with three other common models， including support vector machine， random forest and artificial neural network.ResultsThe classification accuracy of eight mycotoxins in wheat using the combination of borderline-SMOTE， PCA and KNN model reached 98.31%， and the performance of this approach was superior to other frequently used methods.ConclusionThe classification model established in this paper can effectively categorize the wheat samples into three climate regions based on the co-occurrence characteristics of mycotoxins， which provides a basis for region-specific cumulative risk assessment of combined mycotoxin exposure and puts forward a food classification method based on multiple food safety indicators.

Objective To investigate the relevant risk factors of high-risk human papillomavirus(HR-HPV) infection. Methods From October 2020 to January 2021, the cases of positive HR-HPV test were selected as the infection group, and the cases of negative HR-HPV test were selected as the control group. Both groups of patients filled in self-designed 'survey of HR-HPV infection-related factors' in order to explore the relevant risk factors. Results A total of 125 patients in the infection group and 53 patients in the control group were included. Univariate analysis showed that there were statistically significant differences between the two groups in the following factors: unemployed or low socioeconomic status, vulva cleaning with lotion, high frequency of vaginal irrigation, homosexual orientation, production number, history of vaginitis, large amount of vaginal secretions, abnormal characteristics of vaginal secretion and chlamydia trachomatis infection(all P < 0.05). Logistic regression analysis showed that production number(OR=5.106, 95% CI: 1.521-17.145, P=0.008), previous history of vaginitis (OR=3.910, 95% CI: 1.167~13.099, P=0.027) and abnormal vaginal secretion (OR=758.313, 95% CI: 58.151~9888.714, P < 0.001) were risk factors for HR-HPV infection. In addition, the habit of using lotion to clean the vulva or vagina(OR=2.004), homosexual orientation (OR=13.972), and chlamydia trachomatis infection (OR=15.058) all showed a strong association with HR-HPV, but due to the small number of samples in the control group, no conclusions with statistical significance were drawn. Conclusions HR-HPV papillomavirus infection is associated with a variety of factors. Production number, history of vaginitis and abnormal characteristics of vaginal secretion are risk factors for HR-HPV infection. It is therefore recommended to pay attention to the characteristics of vaginal secretions, and timely seek medical treatment if there is any abnormality. If possible, cervical HR-HPV screening should be added to the vaginal microecological examination. If there are reproductive tract inflammatory diseases, it should be treated in time, so as to prevent HR-HPV infection from many aspects and reduce the risk of continuing infection of HR-HPV.

ObjectiveTo estimate the global prevalence and concentration of deoxynivalenol （DON）， aflatoxins （AFs）， zearalenone （ZEN）， nivalenol （NIV）， T-2 toxin （T2）， HT-2 toxin （HT2）， ochratoxin A （OTA）， fumonisins （FBs）， alternariol （AOH）， alternariol monomethyl ether （AME）， tentoxin （TEN） and tenuazonic acid （TeA） in wheat and wheat-based products via Meta-analysis.MethodsThe databases include PubMed， Web of Science， CNKI and WANFANG database.ResultsA total of 69 eligible studies were included in this study， related to 22，308 samples. The global pooled prevalence of mycotoxins in wheat and wheat-based products was 58% （95%CI： 51%-66%）， which mainly were TeA （99%）， TEN （88%）， DON （85%）， AFs （57%）， ZEN （42%）， T2 （39%）， AOH （30%）， AME （29%）， NIV （28%）， HT2 （25%）， OTA （21%） and FBs （16%）. The global pooled concentration of mycotoxins in wheat and wheat-based products was 32.80 μg/kg （95%CI： 24.96-43.10 μg/kg）. DON showed the highest concentration （317.53 μg/kg）， followed by TeA （117.37 μg/kg）， FBs （45.09 μg/kg）. The co-occurrence rate of DON-ZEN was 11.0%, 14.0% and 26.7%, TeA-TEN was 16.2%, TeA-TEN-AME was 14.3% and TeA-TEN-AOH-AME was 19.5%, respectively.ConclusionWheat and wheat-based products showed different characteristics of mycotoxin contamination in different countries or regions, and the co-occurrence rate of more than one mycotoxin in wheat and wheat-based products was high, which should be paid attention to in the combined exposure assessment.

ObjectiveTo analyze the correlation of muti-mycotoxin contamination in wheat， the co-contamination characteristics of different mycotoxins were studied.MethodsData mining analysis of the association between monitoring data for multiple mycotoxins contamination in wheat was performed using the association rule Apriori algorithm. Boolean data type of transaction database was constructed according to the pollutant index values to risk hierarchy structure to mine frequent item sets of transaction database. To determine frequent item sets and obtain strong association rules， minimum threshold support and minimum confidence was set， and iterative connection and pruning operations were performed repeatedly. Association rules were evaluated by confidence， support and promotion degree， etc. Finally， data visualization was applied to association rules to display and verify rules more intuitively.ResultsThe potential strong association rules of co-contamination of muti-mycotoxins in wheat were found， including 9 strong association rules of single common contamination toxin and several strong association rules of combined term sets. The co-pollution relationship between deoxynivalenol and nivalenol， zearalenone and deoxynivalenol was analyzed and verified. The confidence was 92.0% and 80.6%， respectively.ConclusionThe strong association rules obtained by data mining have certain significance for the early warning， prevention and control of wheat toxin risk， which provides basis for the assessment of combined exposure to multiple toxins.

Objective To investigate the detection rate of vaginal intraepithelial neoplasia (VaIN) in women without hysterectomy, and explore its correlation with high-risk types of human papillomavirus (HPV) and cervical lesions, and the role and suggestions of liquid-based cytology in screening VaIN. Methods The clinical data of 96 VaIN patients who did not have hysterectomy history selected from 3 084 patients undergoing colposcopy in our department from June 2019 to July 2020 were collected and retrospectively analyzed. The detection rate, onset age, type of susceptible HPV, the relationship between HPV and cervical lesions and the predictive value of liquid-based cytology in VaIN were analyzed. Results The detection rate of VaIN in people without hysterectomy was 3.11% (96/3 084), in which, 24 cases (25.0%) of high-grade VaIN and 72 cases (75.0%) of low-grade VaIN were found. The patients infected with 2 or more high-risk HPV subtypes had a higher incidence of high-grade VaIN than those infected with only 1 type (P=0.019). There was no correlation between cervical intraepithelial neoplasia and the presence of high-grade vaginal intraepithelial neoplasia (P=0.904). No difference in cytological results was seen between high-grade and low-grade VaIN groups (P=0.264). Conclusion The patients without hysterectomy with the infection of 2 or more sub-types of high-risk HPV have a higher risk of high-grade VaIN compared to those infected by only 1 high-risk sub-type. There is no relationship between cervical lesions and different grades of VaIN. For the high-risk population of VaIN, cytological sampling of vaginal wall can be carried out separately and specifically.

Two rice genotypes Huanghuazhan (HHZ, heat-resistant) and IR36 (heat-susceptible) were subjected to high-temperature (HT, 40 °C) and normal-temperature (NT, 32 °C) treatments at the spikelet differentiation stage. HT treatment inhibited spikelet differentiation, aggravated spikelet degeneration, reduced spikelet size, and disordered carbohydrate allocation. Meanwhile, HT treatment increased nonstructural carbohydrate content in leaves, but decreased that in stems and young panicles, and the same tendencies of sucrose and starch contents were observed in leaves and stem. However, HT treatment significantly increased the sucrose content and sharply decreased the glucose and fructose contents in young panicles. Lower activity levels of soluble acid invertase (EC3.2.1.26) and sucrose synthase (EC2.4.1.13) were observed under HT treatment. Moreover, HT treatment reduced the activities of key enzymes associated with glycolysis and the tricarboxylic acid cycle, which indicated sucrose consumption was inhibited in young panicles under HT treatment. Exogenous glucose and fructose applied under HT treatment increased the spikelet number more than exogenous sucrose. In conclusion, the results demonstrated that the reduction of spikelet number under high temperature was more affected by the decrease in sugar consumption than the blocking of sucrose transport. The impairment of sucrose hydrolysis was the main reason for the inhibition of sugar utilization. Keywords: Rice, High temperature, Panicle development, Spikelet number, Carbohydrate allocation, Sugar consumption

In order to compare the health literacy level of college students in Guangdong province in 2020 and 2022, so as to provide a scientific basis for targeted health literacy intervention and policy formulation for college students in Guangdong province, surveys were respectively conducted in 2020 and 2022. The data collation and analysis were performed using SPSS 19.0 statistical software. The χ2 test was used to compare different health literacy, and logistic regression was performed to analyse the factors influencing health literacy. The results show that the general health literacy level of college students in Guangdong province in 2022 is 46.5%, 6.3% higher than 40.2% in 2020, which difference is statistically significant. The three dimensions and six aspects of health literacy all have improved. The results of both years showed that health skills, basic medical literacy and health information literacy were at a low level. According to logistic regression analysis, the health literacy level of senior students is higher than that of junior students，and those who have taken health related courses have higher health literacy level. The most desirable type of health knowledge is prevention and treatment of infectious diseases, and the new media access is becoming more popular among students to gain health knowledge. In conclusion, Guangdong college students’ health literacy is relatively high, but still needs to be improved, especially in health skills, basic medical care and health information literacy. The government, colleges and universities should work together to improve college students’ health literacy.

This paper presents the efficient modeling and analysis of laminated composite plates using an eightnode quasi-conforming solid-shell element, named as QCSS8. The present element QCSS8 is not only lockingfree, but highly computational efficiency as it possesses the explicit element stiffness matrix. All the six components of stresses can be evaluated directly by QCSS8 in terms of the 3-D constitutive equations and the appropriately assumed element strain field. Several typical numerical examples of laminated plates are solved to validate QCSS8, and the resulting values are compared with analytical solutions and the numerical results of solid/solidshell elements of commercial codes computed by the present authors in which fine meshes were used. The numerical results show that QCSS8 can give accurate displacements and stresses of laminated composite plates even with coarse meshes. Furthermore, QCSS8 yields also accurate transverse normal strain which is very important for the evaluation of interlaminar stresses in laminated plates. Since each lamina of laminated composite plates can be modeled naturally by one or a few layers of solidshell elements and a large aspect ratio of element edge to thickness is allowed in solid-shell elements, the present solid-shell element QCSS8 is extremely appropriate for the modeling of laminated composite plates.

This paper analyses a frequency domain performance of an adaptive windowing parabolic sliding mode filter (AW-PSMF) by using Describing Function method. The analysis results show that AW-PSMF has similar gain characteristics to that of the second-order Butterworth low-pass filter (2-LPF), but AW-PSMF produces flatter gain behaviour than 2-LPF does at cutoff frequency. In addition, AW-PSMF produces smaller phase lag than 2-LPF does.