[The development and national norm of the assessment of spinal health of youths].

Objective: To develop the Assessment of Spinal Health of Youths (ASHY), and evaluate its reliability and construct validity and further definite the national norm. Methods: According to literature review and expert consultation, the ASHY included 37 items within 4 dimensions, named symptoms of neck-shoulder and low back, the dysfunction of neck-shoulder and low back, daily risk behaviors and health-seeking behaviors. Between December 2015 and March 2016, a total of 15 096 students were purposively selected from Shenyang, Zhengzhou, Shenzhen and Jiangxi province. Item analysis, factor analysis and reliability evaluation methods were used to select items and evaluate the questionnaire. Between November 2017 and January 2018, a total of 14 500 students were purposively selected from Shenzhen, Zhengzhou, Nanchang and Guiyang. These data were used to develop a national norm of ASHY in adolescents. Results: The ASHY consisted of 4 dimensions covering 34 items. Variance cumulative contribution rate was 68.37%. Internal consistency test showed that Cronbach's α coefficient of the questionnaire was 0.91 and Cronbach's α coefficient of each dimension was between 0.76 and 0.93. The split-half coefficient of the questionnaire was 0.78 and ranged from 0.62 to 0.77 for each dimension. Confirmatory factor analysis results showed that the value of RMSEA was 0.067, and the values of NFI, RFI, CFI, GFI, AGFI were all above 0.80, which had a good fitting degree. The 90th percentile was used as the cutoff point about total scores of 92 for junior high school students, 102 for senior high school students and 98 for the overall middle school students. Conclusions: The ASHY is consistent with the evaluation standard of psychometrics. It can be used as a tool to evaluate the spinal health in adolescents.

[Effects of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children].

Objective: To explore the effect of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children. Methods: From October to November 2017, 27 987 children aged 3 to 6 years old from 109 kindergartens in 11 cities of Hubei, Anhui and Jiangsu Provinces were selected by using the cluster sampling method. A total of 27 200 valid questionnaires which were completed by subjects' parents were collected. The emotional and behavioral problems of preschool children were collected by "strengths and difficulties questionnaire" and the parental rearing patterns were evaluated by the "Parental Behavior Scale". The differences in emotional and behavioral abnormality rates of preschool children with different characteristics were analyzed; with emotional and behavioral problems as dependent variables and parental support/participation and compulsion/hostility as independent variables, the multivariate logistic regression model was used to analyze the effect of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children. Results: The age of children was (4.35±0.96) years old, and 51.4% of children were 13 975 males. There were 24 634 (90.6%) urban children and 17 916 (65.9%) only children. Both parents with strong support/participation accounted for 14.9%, and those with poor support/participation accounted for 11.9%; both parents with strong compulsion/hostility accounted for 15.2%, and those with low compulsion/hostility accounted for 11.3%. The rates of emotional symptoms, conduct behavior, hyperactive behavior, peer interaction, total difficulty score, and abnormal prosocial behavior of preschool children were 9.5%, 9.5%, 18.2%, 24.5%, 11.2%, and 10.2%, respectively. The multivariate logistic regression model analysis showed that after adjusting for gender, only child, living area, family economic status, mother's age and education level, father's education level, and other factors, compared with fathers/mothers with strong support/participation and low compulsion/hostility and parents with strong support/participation and low compulsion/hostility, preschool children who had fathers/mothers with poor support/participation and strong compulsion/hostility or parents with poor support/participation and strong compulsion/hostility were more likely to have emotional symptoms, conduct behavior, hyperactive behavior, peer interaction, total difficulty score, and abnormal prosocial behavior (P<0.05). Conclusions: Parental rearing patterns and their consistency are related to the emotional and behavioral problems of preschool children.

[Cost-effectiveness analysis of cervical cancer screening strategies in urban China].

Objective: To explore the most economically feasible cervical cancer screening strategies in urban China. Methods: A series of Markov models were constructed to evaluate health and economic outcomes of different screening strategies. There were 24 screening strategies including four screening methods: liquid-based cytology (LBC), human papillomavirus (HPV) DNA genotyping, HPV DNA genotyping with LBC triage (HPV DNA+ LBC), HPV DNA genotyping and LBC co-testing (HPV DNA-LBC), along with three intervals (every 1, 3 or 5 years) and two starting age for screening (30 or 35 years old) were compared. Models parameters were obtained from a cervical cancer screening study in urban China and literature reviews. Results: The cumulative incidence and mortality risk of cervical cancer declined over 69% and 82% respectively for each screening strategy as compared with the no screening scenario. LBC every five years starting from 35 years old strategy cost the least (RMB 690 per capita) and could save life years compared with no screening. The cost effectiveness ratios of 24 strategies ranged from -10 903 to 117 992 RMB per life year saved. All strategies were cost-effective compared to no screening. In the incremental cost-effectiveness analysis, LBC every 5 years starting from 30 strategy, HPV DNA genotyping every 3 years starting from 30 strategy, LBC every 3 years starting from 30 strategy and LBC every year starting from 30 strategy were dominant strategies. Conclusions: Screening can effectively prevent cervical cancer. In urban Chinese areas with insufficient socioeconomic resources, LBC every 5 years from 35 years old strategy is recommended. In relatively more affluent areas, LBC every 5 years from 30 years old strategy, LBC every 3 years from 30 years old strategy, HPV DNA genotyping every 3 years from 30 years old strategy, and LBC every year from 30 years old strategy are recommended successively.

[Study on direct economic burden and influencing factors in patients with cervical cancer and precancerous lesions].

Objective: To account the direct cost of uterine cervix carcinoma treatment in China and to explore the related factors which influence the direct financial burden of the disease. Methods: Data was collected through the medical record system and telephone interviews in 14 county-level hospitals and 9 provincial and municipal hospitals from 14 provinces/municipalities enrolled in the Chinese National Health Industry Research Project in 2015. The direct financial burden of uterine cervix carcinoma treatment consisted of the direct medical cost and the direct non-medical cost of treatment in different pathological cervical cancer stages and precancerous lesions. Multiple liner regression method was used to analyze the factors affecting the costs. Results: The age of the 3 246 patients was (46.40±10.43) years, including 2 423 patients from provincial and municipal hospitals and 823 patients from county-level hospitals. The direct financial burden for one patient of pathological uterine cervix carcinoma stage or precancerous lesion ranged from 10 156.3 yuan to 75 716.4 yuan in provincial and municipal hospitals, and for patients from county-level hospitals, the cost was between 4 927.9 yuan and 47 524.8 yuan per person. There was a wide gap between the direct financial burden of patients in different disease stages. The direct financial burden of patients with precancerous lesions ranged from 4 927.9 yuan per person to 11 243.0 yuan per person, as for patients of pathological uterine cervix carcinoma stages, the direct financial burden was between 29 274.6 yuan and 75 716.4 yuan per person. The factors which influence direct financial burden would include: the levels of the hospital, pathological period, medicare reimbursement, days of treatment, and the methods of treatment (P<0.001). Conclusion: The direct financial burden of diseases in patients with pathological uterine cervix carcinoma stage or precancerous lesion differed in different levels of hospital and pathological periods. In addition, medicare reimbursement, days of treatment, and the methods of treatment all had impact on it.

Handwashing behaviour among Chinese adults: a cross-sectional study in five provinces.

OBJECTIVES: To describe the patterns of handwashing behaviour among Chinese adults, and assess their associations with sociodemographic factors and knowledge of hand hygiene. STUDY DESIGN: A representative sample (n = 6159) of Chinese adults aged 18-60 years in five provinces was attained by multiple-stage, stratified sampling mainly based on geographical location and economic status. Data on handwashing behaviour, knowledge of hand hygiene and sociodemographic factors were collected through self-administrated questionnaires. METHODS: Associations between handwashing behaviour and sociodemographic factors were tested in logistic models. Path analysis was applied to examine the associations between sociodemographic factors, knowledge of hand hygiene and proper handwashing behaviour in order to evaluate the relative magnitude of these determinants and internal relationships. RESULTS: This study found that 52.7% (rural vs urban: 44.6% vs 56.8%) and 67.3% (rural vs urban: 59.7% vs 71.1%) of Chinese adults reported they always washed hands before eating and after defaecation, and 30.0% (rural vs urban: 25.1% vs 32.8%) of adults always used soap or other sanitizers during washing. Using the criteria of 'always or very often washing hands with soap before eating and after defaecation without sharing a towel with family members after washing', only 47.2% (rural vs urban: 23.8% vs 59.1%) of the adults were graded to practice proper handwashing behaviour. Urban area, high level of education level, high level of knowledge about diseases, female gender and older age were protective factors for good hand hygiene; of these, area was found to be associated most strongly with handwashing behaviour. CONCLUSIONS: Adherence to an appropriate handwashing method and duration of handwashing are critical problems among Chinese adults. Area difference, level of education and level of knowledge of hand hygiene were most strongly associated with handwashing behaviour, and should be targeted in future health education.

Risk assessment of PCDD/Fs levels in human tissues related to major food items based on chemical analyses and micro-EROD assay.

Nine groups of food items (freshwater fish, marine fish, pork, chicken, chicken eggs, leafy, non-leafy vegetables, rice and flour) and three types of human samples (human milk, maternal serum and cord serum) were collected for the analysis of PCDD/Fs. Results of chemical analysis revealed PCDD/Fs concentrations (pg g(-1) fat) in the following ascending order: pork (0.289 pg g(-1) fat), grass carp (Ctenopharyngodon idellus) (freshwater fish) (0.407), golden thread (Nemipterus virgatus) (marine fish) (0.511), chicken (0.529), mandarin fish (Siniperca kneri) (marine fish) (0.535), chicken egg (0.552), and snubnose pompano (Trachinotus blochii) (marine fish) (1.219). The results of micro-EROD assay showed relatively higher PCDD/Fs levels in fish (2.65 pg g(-1) fat) when compared with pork (0.47), eggs (0.33), chicken (0.13), flour (0.07), vegetables (0.05 pg g(-1) wet wt) and rice (0.05). The estimated average daily intake of PCDD/Fs of 3.51 pg EROD-TEQ/kg bw/day was within the range of WHO Tolerable Daily Intake (1-4 pg WHO-TEQ/kg bw/day) and was higher than the Provisional Tolerable Daily Intake (PMTL) (70 pg for dioxins and dioxin-like PCBs) recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) [Joint FAO/WHO Expert Committee on Food Additives (JECFA), Summary and conclusions of the fifty-seventh meeting, JECFA, 2001.]. Nevertheless, the current findings were significantly lower than the TDI (14 pg WHO-TEQ/kg/bw/day) recommended by the Scientific Committee on Food of the Europe Commission [European Scientific Committee on Food (EU SCF), Opinions on the SCF on the risk assessment of dioxins and dioxin-like PCBs in food, 2000.]. However, it should be noted that micro-EROD assay overestimates the PCDD/Fs levels by 2 to 7 folds which may also amplify the PCDD/Fs levels accordingly. Although the levels of PCDD/Fs obtained from micro-EROD assay were much higher than those obtained by chemical analysis by 2 to 7 folds, it provides a cost-effective and rapid screening of dioxin levels in food and human samples.

Modeling the dynamic changes in concentrations of gamma-hexachlorocyclohexane (gamma-HCH) in Tianjin region from 1953 to 2020.

A level IV fugacity model was used to simulate the dynamic changes of gamma-hexachlorocyclohexane (gamma-HCH) concentrations in environmental media in Tianjin, China. A similar model (level III) was previously used and validated under steady state conditions; this paper explores its dynamic behavior. Application of the level IV fugacity model has been validated using independently observed gamma-HCH concentrations in various media during the early 1980s and during 2001. Sensitivity analysis was conducted using coefficient-of-variation normalized sensitivity coefficients. The model was also subject to uncertainty analysis using Monte Carlo simulation. It was found that concentrations of gamma-HCH reached within 95% of their steady-state levels in all media after less than 15 years. Around one order-of-magnitude decreases in gamma-HCH concentrations in various media occurred between 1993 and 2001. We project that gamma-HCH concentrations will decrease another 1.7-1.9 orders of magnitude to reach 1.1 (0.9-1.2) x 10(-14), 2.7 (2.5-3.0) x 10(-10), 1.2 (1.1-1.3) x 10(-7), and 6.1 (5.4-6.8) x 10(-8) mol/m(3), in air, water, soil, and sediment, respectively, by 2020. The sensitivities and true uncertainty of the model are discussed.

Human exposure and health risk of alpha-, beta-, gamma- and delta-hexachlorocyclohexane (HCHs) in Tianjin, China.

The dynamic exposures to HCHs of individuals born between the years 1913 and 1993 in Tianjin have been simulated by connecting a fugacity model (IV) with a multimedia exposure model. Ingestion is the most important pathway for human beings to take up HCHs, and concentrations in the human body correlate with body weight changes. Accumulations of HCHs were derived assuming that the degradation in human body behaved linearly. The health risk of exposure to HCHs was measured using cancer risk and loss of life expectancy (LLE), and LLE was modified from its original definition to incorporate a dynamic calculation that takes variances in exposure into account. Monte-Carlo simulations were run to analyze the uncertainties of the model.

Uncertainty analysis of parameters for modeling the transfer and fate of benzo(a)pyrene in Tianjin wastewater irrigated areas.

A Monte Carlo simulation for uncertainty analysis of three key parameters (local coal consumption rate Q(1L), dry deposition velocity of aerosol particulate Kp and biodegradation rate of benzo(a)pyrene in soil and sediment K(R3)) was conducted in this study. Results of the simulation indicate that the three parameters were influenced by uncertainty and that all equilibrium concentrations in the four bulk compartments and various sub-compartments were log-normally distributed. However, the results also indicated that among the six primary transfer fluxes, erosion associated with solids in soil and deposition associated with solids in water, along with output from sewers were also log-normally distributed, while deposition from air to soil and biodegradation in soil and sediment followed normal distributions. The effect of uncertainty on the model results of the three key parameters was derived using a comparison of upper and lower of confidence interval boundaries at the 95% level of confidence. The results reveal that uncertainty in the key parameters had a more significant influence on equilibrium concentrations of the chemical in the bulk compartments of soil and sediment than on concentrations in the other two bulk compartments, various sub-compartments and the six predominant transfer fluxes.

Low-cost and efficient coupling technique using reflowed sol-gel microlens.

In this paper, we present a novel reflow technique for the fabrication of an elliptical microlens array in sol-gel glass. The fabricated refractive microlens array has a very smooth surface, and structural and dimensional conformity with the designed parameters. It is shown that the microlens array can provide high coupling efficiency of a laser diode to a single mode fiber, and relax the lateral and axial misalignment tolerance. The microlens coupling technique has the advantages of low coupling loss, large misalignment tolerances, and small package volume.

Lake ecosystem health assessment: indicators and methods.

A set of ecological indicators including structural, functional, and system-level aspects were proposed for a lake ecosystem health assessment, according to the structural, functional, and system-level responses of lake ecosystems to chemical stresses including acidification, eutrophication and copper, oil and pesticide contamination. The structural indicators included phytoplankton cell size and biomass, zooplankton body size and biomass, species diversity, macro- and micro-zooplankton biomass, the zooplankton phytoplankton ratio, and the macrozooplankton microzooplankton ratio. The functional indicators encompassed the algal C assimilation ratio, resource use efficiency, community production, gross production/respiration (i.e. P/R) ratio, gross production standing crop biomass (i.e. P/B) ratio, and standing crop biomass unit energy flow (i.e. B/E) ratio. The ecosystem-level indicators conisisted of ecological buffer capacities, energy, and structural energy. Based on these indicators, a direct measurement method (DMM) and an ecological modeling method (EMM) for lake ecosystem health assessment were developed. The DMM procedures were designed to: (1) identify key indicators; (2) measure directly or calculate indirectly the selected indicators; and, (3) assess ecosystem health on the basis of the indicator values. The EMM procedures were designed to: (1) determine the structure and complexity of the ecological model according to the lake's ecosystem structure; (2) establish an ecological model by designing a conceptual diagram, establishing model equations, and estimating model pararmeters; (3) compare the simulated values of important state variables and process rates with actual observations; (4) calculate ecosystem health indicators using the ecological model; and, (5) assess lake ecosystem health according to the values of the ecological indicators. The results of a case study demonstrated that both methods provided similar results which corresponded with the lake's actual trophic state.

Multi-country comparison of plasma lipid relationship to years of schooling in men and women.

BACKGROUND: The association between coronary heart disease (CHD) and social status has differed among societies in strength and direction. As years of schooling is a major determinant of socioeconomic status and dyslipidaemia a major CHD determinant, the purpose of this investigation is to estimate the association of years of schooling with plasma lipids and lipoproteins among samples from five countries representing different cultures, socio-political systems and stages of economic development. METHODS: Men and women from Chinese, Polish, Russian, Israeli and US samples were studied. Years of schooling were analysed both as a multi-category ordinal variable and divided into two strata: less than the equivalent of high school and greater than or equal to high school equivalence. Fasting plasma cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol and triglycerides were compared across years of schooling strata within each country. Lipid levels were computed unadjusted and then adjusted for age and lipid risk factor variables. RESULTS: Total cholesterol, LDL cholesterol, and triglycerides varied directly with years of schooling in Chinese, Polish and Russian men, and in contrast varied inversely with years of schooling among US white men. The HDL cholesterol varied inversely with years of schooling for Chinese, Polish, and Russian men, but varied directly with years of schooling among US white men. The lipid differences between men of high versus low years of schooling were not explained by age, body mass index, smoking, alcohol consumption or blood pressure medication use. Findings were less consistent for women and for Israelis and US blacks of both genders. CONCLUSIONS: Lipid and lipoprotein levels consistent with atherogenicity varied directly with years of schooling in Chinese, Polish, and Russian samples. Opposite trends were present in US whites. These findings are consistent with a hypothesized influence of social status on CHD risk differing among populations in relation to stages in societal economic development.

Hazard assessment of germanium supplements.

Germanium-containing dietary supplements became popular in the 1970s in Japan and later in other countries, as elixirs for certain diseases (e.g., cancer and AIDS). Germanium is not an essential element. Its acute toxicity is low. However, at least 31 reported human cases linked prolonged intake of germanium products with renal failure and even death. Signs of kidney dysfunction, kidney tubular degeneration, and germanium accumulation were observed. Other adverse effects were anemia, muscle weakness, and peripheral neuropathy. Recovery of renal function is slow and incomplete even long after germanium intake was stopped. The total dose of ingested germanium (as dioxide, carboxyethyl germanium sesquioxide, germanium-lactate-citrate, or unspecified forms) varied from 15 to over 300 g; the exposure duration varied from 2 to 36 months. In laboratory animals, elevated germanium in tissues and impaired kidney and liver function were observed in a life-time drinking water (5 ppm germanium) study. Other toxicities associated with ingested germanium products in human cases were also demonstrated in animal studies with germanium dioxide and sometimes other germanium compounds. Based on the evidence of persistent renal toxicity associated with germanium dioxide, the lack of conclusive findings of differential nephrotoxicity of organic germanium compounds, and the possibility of contamination of the organic germanium products with inorganic germanium, it is clear that germanium products present a potential human health hazard.