Objective:To learn about the implementation of prevention and control measures in drinking water-borne endemic fluorosis areas and the trend of the disease change in Jiangsu Province.Methods:In March to October 2021, a general survey was carried out in 1 972 villages with drinking water-borne endemic fluorosis in 27 counties (cities and districts) of Jiangsu Province, the operation of water improvement projects in the villages was monitored, and the water fluoride content was determined. The prevalence of dental fluorosis among children aged 8 to 12 years in all the villages was investigated.Results:The 1 972 villages with drinking water-borne endemic fluorosis had completed water improvement, and all water improvement projects were operating normally and the water was qualified. Among them, 1 774 villages in the disease affected areas had achieved the control goal, accounting for 89.96%; and there were 198 villages in the disease affected areas with control measures up to the standard, accounting for 10.04%. A total of 47 water improvement projects were monitored, including 2 small-scale water improvement projects, accounting for 4.26%. There were 45 large-scale water improvement projects, accounting for 95.74%. A total of 125 790 children aged 8 to 12 years were examined, and 12 625 cases of dental fluorosis were detected. The detection rate of dental fluorosis was 10.04%, and the dental fluorosis index was 0.19. The detection rate of dental fluorosis in children aged 8 to 12 years was 9.98% (1 854/18 579), 10.27% (2 704/26 323), 9.48% (2 765/29 152), 9.73% (2 835/29 145) and 10.92% (2 467/22 591), respectively, with statistically significant difference (χ 2 = 10.51, P = 0.015). Among the 198 villages with control measures up to standard, according to the historical water fluoride, the detection rate of dental fluorosis in children in each water fluoride range (1.20-2.00, 2.01-3.00, 3.01-4.00, > 4.00 mg/L) was 37.73% (698/1 850), 43.17% (1 176/2 724), 45.50% (769/1 690) and 55.20% (802/1 453), respectively, with a statistically significant difference (χ 2 = 104.15, P < 0.001). Conclusion:The water improvement measures in drinking water-borne endemic fluorosis areas in Jiangsu Province have achieved significant results, which still need to be further consolidated.

Objective:To dynamically observe the changes in iodine level in residents' drinking water after the change of regional water supply mode (2020) in Jiangsu Province.Methods:The survey of water iodine level was conducted from June to October 2020 in administrative villages of Jiangsu Province with a median water iodine ≥40 μg/L in 2017. The survey mainly covered 1 537 administrative villages in 21 counties (cities and districts) of 5 cities, including Huaian City, Lianyungang City, Suqian City, Yancheng City, and Xuzhou City. Based on the standard of "Definition and Demarcation of Iodine Deficient Areas and Iodine Adequate Areas" (WS/T 669-2020), the administrative villages with a median water iodine of 40 - 100 μg/L were classified as iodine adequate areas. Water iodine testing was conducted using the "Method for Water Iodine Testing in Iodine Deficient and High Iodine Areas" recommended by the National Reference Laboratory for Iodine Deficiency Disorders.Results:Totally 1 498 administrative villages in Jiangsu Province were monitored in 2020, all of which had centralized water supply. The minimum value of water iodine in all administrative villages was 1.2 μg/L and the maximum value was 606.7 μg/L, and the median water iodine was 35.2 μg/L. Among them, 206 administrative villages had median water iodine < 10 μg/L, accounting for 13.75% (206/1 498); 610 administrative villages had median water iodine from 10 to < 40 μg/L, accounting for 40.72% (610/1 498); 635 administrative villages had median water iodine from 40 to 100 μg/L, accounting for 42.39% (635/1 498); and 47 administrative villages with median water iodine > 100 μg/L, accounting for 3.14% (47/1 498). Except for Sucheng District in Suqian City, Xinyi City and Gulou District in Xuzhou City, Qingjiangpu District and Xuyi County in Huaian City, and Guannan County in Lianyungang City, the median water iodine in the administrative villages of the remaining 15 counties (cities and districts) in 2020 decreased significantly compared to 2017, and the differences were statistically significant ( P < 0.05). Conclusion:After change of regional water supply mode in 2020, in most monitored counties (cities and districts) of Jiangsu Province, the water iodine level of administrative villages has decreased significantly compared to 2017.

Abstract Hydrogels are widely used in biomedical fields such as drug delivery, wound dressings and tissue engineering because of their good biocompatibility and biodegradability. According to the source of material, it can be divided into synthetic material hydrogel and natural material hydrogel. Natural polysaccharide hydrogel not only can be used as material, but also has unique pharmacological activity and better mechanical properties, gradually become the preferred material. Dynamic covalent hydrogels have attracted much attention due to their structural flexibility, self healing performance and environmental responsiveness. In this paper, the dynamic bond mode natural polysaccharide hydrogel systems are classified and summarized, and the research status of the construction of this kind of hydrogel in drug delivery and tissue repair are summarized, to provide reference for the application of new polysaccharide hydrogels in clinical application.

Objective:To analyze the iodine nutrition status of key populations in water source high iodine areas in Jiangsu Province, providing a reference for scientific prevention and control of water source high iodine hazards.Methods:From May to June 2020, monitoring sites were determined by administrative villages in six high iodine counties (cities, districts) in Jiangsu Province, and drinking water samples were collected from residents to detect the iodine content in the water; 40 non boarding children aged 8 - 10 from one primary school in each village (half male and half female, with an age balance) and 20 pregnant women were selected. Salt samples were taken from children and pregnant women's homes, and urine samples were randomly taken once to detect salt and urine iodine contents. Thyroid volume of children was examined.Results:A total of 36 administrative villages were monitored, with a median of 45.3 μg/L for water iodine, ranging from 8.5 - 372.1 μg/L. A total of 1 422 salt samples were collected, of which 26 were iodized salt, accounting for 1.83%; and 1 396 non iodized salt, with the coverage rate of non iodized salt was 98.17%. A total of 1 365 urine samples were collected from children, with a median urine iodine of 405.6 μg/L. There were statistically significant differences in urine iodine levels among children in different regions, drinking water iodine contents, and age groups ( H = 128.39, 67.81, 39.94, P < 0.001). A total of 57 urine samples were collected from pregnant women, with a median urine iodine of 282.0 μg/L. There were statistically significant differences in urine iodine levels among pregnant women in different regions and drinking water iodine contents groups ( H = 17.54, 18.39, P < 0.001). A total of 1 365 children's thyroid volumes were examined, and 44 cases of thyroid enlargement were detected, with a goiter rate of 3.22%. There were no statistically significant differences in the incidence of thyroid enlargement among children in different regions, drinking water iodine contents, salt types, gender, and age groups ( P > 0.05). Conclusions:The iodine nutrition of children in water source high iodine areas in Jiangsu Province is at an iodine excess level, while the iodine nutrition of pregnant women is at an over optimal level. In areas with high iodine content in water sources, the iodine content in drinking water has a significant impact on the iodine intake of the local population. There is currently no correlation between the iodine content in drinking water, salt type, gender, and age factors and thyroid enlargement in children.

Objective:To analyze the detection rate of thyroid nodules and goiter in school-age children in different water iodine regions and investigate the difference of thyroid nodule and goiter in school-age children with different age, gender and body mass index (BMI) in Jiangsu Province.Methods:In 2017, three villages with water iodine values of 8.1, 51.2 and 115.4 μg/L (iodine deficient group, iodine appropriate group and iodine high group) were selected as survey sites in Xuzhou City, Jiangsu Province, where the supply of iodized salt was suspended. One primary school was selected from each village, and children aged 8 to 10 years old (age balance, half male and half female) were selected from each primary school as the survey subjects. Urine sample were collected, urinary iodine level was determined, height and weight were measured, and neck B ultrasound was performed.Results:A total of 131, 140 and 138 school-age children aged 8 to 10 years old were investigated in the iodine deficient group, iodine appropriate group and iodine high group, respectively, with a total of 409 children. The detection rates of thyroid nodules were 6.9% (9/131), 15.0% (21/140) and 16.7% (23/138), respectively, and the detection rates of goiter were 1.5% (2/131), 1.4% (2/140) and 6.5% (9/138) in the three groups, respectively. There were statistically significant differences in the detection rates of thyroid nodules and goiter in different water iodine groups (χ 2 = 6.92, 6.37, P < 0.05). The detection rates of thyroid nodules in different age groups were 9.5% (12/126), 11.3% (16/142) and 17.7% (25/141), the differences were statistically significant (χ 2 = 9.05, P < 0.05). The detection rates of thyroid nodules were 11.6% (24/207), 14.4% (29/202), and 12.5% (39/313), 16.9% (14/83), 0/9 and 0/4 in the subjects of different gender and BMI, the differences were not statistically significant (χ 2 = 0.69, P > 0.05). The detection rates of goiter in the subjects of different gender, age and BMI were 1.4% (3/207), 5.0% (10/202); 2.4% (3/126), 6.3% (9/142), 0.7% (1/141); 1.6% (3/313), 4.8% (4/83), 3/9 and 1/4. The differences were statistically significant (χ 2 = 4.07, 7.66, P < 0.05). Conclusion:The detection rate of thyroid nodules in school-age children in different water iodine regions in Jiangsu Province may have a certain relationship with age, and the detection rate of goiter may have a certain relationship with age, gender and BMI.

Objective:To evaluate the effect of health education on drinking-warter-borne endemic fluorosis in Jiangsu Province.Methods:From 2014 to 2018, a total of 12 counties (districts) with drinking-warter-borne endemic fluorosis were selected to carry out public health education activities, and 3 townships were chosen in each project county (district). School health education activities were carried out in the classes of grade 4 - 6 in the central primary school in each selected twonship. In the meantime, 3 villages were chosen in each selected township where the health education activities in the community were carried out. Before and after the health education activities, questionnaire surveys on knowledge of drinking-warter-borne endemic fluorosis prevention were conducted among 30 students in one class of grade 5 in the central primary school and 15 housewives lived near the central primary school in each township.Results:After the health education activities, the rates of knowledge awareness in the students and the housewives were 94.83% (15 362/16 200) and 95.14% (7 706/8 100), respectively, which were significantly higher than those before the health education activities [63.88% (10 348/16 200) and 65.94% (5 341/8 100)], and the differences were statistically significant (χ 2 = 4 700.00, 2 200.00, P < 0.001). There were no statistical differences in the rates of knowledge awareness in the students and housewives before the health education activities from 2014 to 2018 (χ 2 = 8.43, 0.88, P = 0.077, 0.928). Before the health education activities, the rate of knowledge awareness in the students was lower than that in the housewives, and the difference was statistically significant (χ 2 = 10.03, P = 0.002). After the health education activities, there was no statistical difference between the rate of knowledge awareness in the students and that in the housewives (χ 2 = 1.07, P = 0.301). Conclusions:The rates of knowledge awareness in the students and the housewives are increased significantly after the health education activities. We should expand the coverage of health education. Wide, deep and persistent health education in more ways for different people are needed to consolidate the achievements.

Objective:To investigate the iodine content distribution of drinking water in Jiangsu Province.Methods:In 2017, the iodine content in drinking water of residents in townships (streets, hereinafter referred to as townships) of Jiangsu Province was investigated. Administrative villages (neighborhood committees, hereinafter referred to as administrative villages) of Jiangsu Province were selected as units for the investigation of townships with the median water iodine greater than 10 μg/L. Delimitation criteria: the median iodine content of water < 40 μg/L was iodine deficiency area, 40-100 μg/L was suitable iodine area, and > 100 μg/L was high iodine area.Results:A total of 1 285 townships were surveyed in 101 counties (cities, districts) in 13 cities, and the median water iodine in townships was 7.28 μg/L. Among them, there were 875 townships with median water iodine < 10 μg/L, accounting for 68.09%; 315 townships 10-< 40 μg/L, accounting for 24.51%; 56 townships 40-100 μg/L, accounting for 4.36%; 39 townships > 100 μg/L, accounting for 3.04%. The water iodine survey at the administrative village level was conducted in 5 864 administrative villages in 410 townships in 6 cities. Among them, 769 administrative villages with median water iodine < 10 μg/L, accounting for 13.11%; 3 558 administrative villages 10 - < 40 μg/L, accounting for 60.68%; 613 administrative villages 40 - 100 μg/L, accounting for 10.45%; and 924 administrative villages > 100 μg/L, accounting for 15.76%.Conclusion:According to the water iodine, there are iodine deficiency, suitable iodine and high iodine areas in Jiangsu Province, mainly in iodine deficiency areas.

Objective:To investigate the prevalence of thyroid nodules among students aged 8 - 17 years in Jintan District, Changzhou City, Jiangsu Province, and to explore the risk factors of thyroid nodules among underage students.Methods:In September 2018, two primary and middle schools, one ordinary high school and one vocational high school in Jintan District were selected as the survey sites. Students aged 8 - 17 years were selected as the survey subjects, and questionnaire survey, physical examination and thyroid ultrasound examination were conducted. At the same time, drinking water samples from schools and towns were collected to test water iodine, and urine samples from students and family salt samples were collected to test urinary iodine and salt iodine. Multivariate logistic regression was used to analyze related factors that may affect the occurrence of thyroid nodules.Results:A total of 725 students were surveyed, including 359 (49.5%) boys and 366 (50.5%) girls. Two water samples were collected from each of the four schools, and the mean values of water iodine were 0.3, 8.5, 0.2 and 0.2 μg/L, respectively; two water samples were collected from each of the towns where the four schools were located, and the mean values of water iodine were 6.8, 8.1, 4.8 and 3.7 μg/L, respectively. A total of 725 urine samples were collected, and the median urinary iodine was 209.92 μg/L, ranging from 8.60 to 932.00 μg/L. A total of 725 edible salt samples were collected from students' families, and the salt iodine content was (23.75 ± 7.10) mg/kg, ranging from 0.00 to 60.30 mg/kg, and 95.0% (689/725) of students' families ate iodized salt. A total of 725 students were examined for thyroid gland, and 22 were diagnosed with goiter, with an enlargement rate of 3.0%; and 155 were diagnosed with thyroid nodules, with a detection rate of 21.4%. The detection rates of thyroid nodules in boys and girls were 20.9% (75/359) and 21.9% (80/366), respectively; the detection rates of thyroid nodules in students who participated and did not participate in extracurricular tuition/interest classes in the past month were 28.2% (71/252) and 17.8% (84/473), respectively. The results of multivariate logistic regression analysis showed that girls and participating in extracurricular tuition/interest classes in the past month were independent risk factors for the occurrence of thyroid nodules [odds ratio ( OR) = 2.057, 2.538, 95% confidence interval ( CI): 1.226 - 3.451, 1.532 - 4.204, P < 0.05). Conclusions:The detection rate of thyroid nodules in students aged 8 - 17 years in Jintan District is at a high level. Girls and participating in extracurricular tuition/interest classes in the past month are independent risk factors for the occurrence of thyroid nodules.

Objective:To study a classifier used to classify arrhythmia electrocardiogram (ECG) signals under the inter-patient paradigm to improve the accuracy of automatic classification and solve the limitations of manual diagnosis of arrhythmia.Methods:A SVM+XGBoost ensemble classifier with four modules including preprocessing, feature extraction, support vector machine (SVM) training and ensemble classification was constructed. ECG signal was preprocessed, and R-R interval, high-order statistics, local binary patterns and wavelet components were used as features to train independent SVM classifiers. Then, XGboost algorithm was used to integrate independent SVM classifiers and output arrhythmia classification results. The integrated classifiers were trained and tested on MIT-BIH database.Results:The overall classification accuracy of the ensemble classifier for arrhythmia was 0.867 and the average sensitivity was 0.782.Conclusions:The proposed ensemble classifier can realize automatic and accurate classification of arrhythmia ECG signals under the inter-patient paradigm, and can be used for clinical auxiliary diagnosis.

Objective: To explore the acute effect of fine particulate matters (PM_2.5), O₃, NO₂ on daily non-accidental mortality, cardiovascular disease mortality and respiratory mortality data in thirteen cities of Jiangsu province. Methods: Daily average concentrations of non-accidental mortality, cardiovascular disease mortality, respiratory mortality data and environmental data were collected from January 1, 2015 to December 31, 2017 in thirteen cities of Jiangsu Province. Daily air quality, mortality and meteorology data were collected from the Information System of Air Pollution and Health Impact Monitoring of Chinese Center for Disease Control and Prevention. We used generalized additive model to evaluate the association between daily concentrations of air pollutants and mortality at single-city level and multi-city level, after adjusting the long-term and seasonal trend, as well as meteorological factors and the effect of "days and weeks" . A multivariate Meta-analysis with random effects was applied to estimate dose-response relationship between air pollutants and mortality. Results: At multi-city level, per interquartile range increase of PM_2.5, O₃, NO₂ was associated with an increase of 1.10% (95%CI: 0.66%, 1.54%), 0.59% (95%CI: 0.18%, 1.00%), 2.00% (95%CI: 1.29%, 2.72%) of daily non-accidental mortality respectively; 1.01% (95%CI: 0.63%, 1.38%), 0.66% (95%CI: 0.02%, 1.30%), 1.62% (95%CI: 1.00%, 2.23%) of daily cardiovascular mortality respectively; 1.09% (95%CI: 0.35%, 1.82%), 0.44% (95%CI: -0.29%, 1.16%), 2.75% (95%CI: 1.42%, 4.08%) of daily respiratory mortality respectively. The air pollutants effect varied across different cities. The strongest effect of PM_2.5 was current day (excess risk (ER)=1.10%, 95%CI: 0.66%, 1.54%)), the strongest effect of O₃ was 2-day lag (ER=1.82%, 95%CI: 0.69%, 2.97%) and the strongest effect of NO₂ was 1-day lag (ER=2.09%, 95%CI: 1.34%, 2.83%) of daily non-accidental mortality respectively. Conclusion The increases of PM_2.5 and NO₂ concentration could result in the increases of daily non-accidental mortality, cardiovascular disease mortality and respiratory mortality. O₃ could result in the increases of daily non-accidental mortality and cardiovascular disease mortality. The acute effects for non-accidental mortality from high to low were NO₂, PM_2.5 and O_3, and the strongest effect of PM_2.5 was current day. O₃ and NO₂ had lagged effects.