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The frequency of urban storms has increased, influenced by the climate changing and urbanization, and the process of urban rainfall runoff has also changed, leading to severe urban waterlogging problems. Against this background, the risk of urban waterlogging was analyzed and assessed accurately, using an urban stormwater model as necessary. Most studies have used urban hydrological models to assess flood risk; however, due to limited flow pipeline data, the calibration and the validation of the models are difficult. This study applied the MIKE URBAN model to build a drainage system model in the Beijing Future Science City of China, where the discharge of pipelines was absent. Three methods, of empirical calibration, formula validation, and validation based on field investigation, were used to calibrate and validate the parameters of the model. After the empirical calibration, the relative error range between the simulated value and the measured value was verified by the formula as within 25%. The simulated runoff depth was consistent with a field survey verified by the method of validation based on field investigation, showing the model has good applicability in the study area. Then, the rainfall scenarios of different return periods were designed and simulated. Simulation results showed that, for the 10-year return period, there are overflow pipe sections in northern and southern regions, and the number of overflow pipe sections in the northern region is more than that in the southern region. For the 20-year return period and 50-year return period, the number of overflow pipe sections and nodes in the northern region increased, while for the 100-year return period, the number of overflow nodes both increased. With the increase in the rainfall return period, the pipe network load increased, the points and sections prone to accumulation and waterlogging increased, and the regional waterlogging risk increased. The southern region is prone to waterlogging because the pipeline network density is higher than that in the northern region and the terrain is low-lying. This study provides a reference for the establishment of rainwater drainage models in regions with similar database limitations and provides a technical reference for the calibration and validation of stormwater models that lack rainfall runoff data.

Objective: To investigate the correlation between clinical periodontal indexes of periodontitis and glomerular filtration rate (GFR) in a non-diabetic elderly population in four communities of Shijingshan, Beijing. Methods: This was a cross-sectional study. Questionnaires, blood biochemical examinations, and periodontal indexes were conducted in elderly people (35 to 84 years old) in four communities of Shijingshan, Beijing between May and July 2005. Non-diabetic patients with fasting blood glucose<6.1 mmol/L, postprandial blood glucose<7.8 mmol/L, and ≥ 10 remaining teeth were included. Patients with diabetes, fasting blood glucose ≥6.1 mmol/L or postprandial blood glucose ≥7.8 mmol/L, and total residual teeth less than 10 were excluded. A total of 362 study subjects met the inclusion criteria. The survey subjects were selected by convenient sampling method. The mean full-mouth probing depth (PD), bleeding index (BI), attachment loss (AL), and plaque index (PLI), as well as PD≥4 mm% (the number of sites with PD≥4 mm as a percentage of the total number of sites in full mouth), PD≥5 mm%, PD≥6 mm%, AL≥3 mm%, AL≥4 mm%, AL≥5 mm% and AL≥6 mm% were used for the analysis. Serum creatinine values was used to calculate GFR. GFR≥90 ml/(min·1.73 m 2 ) was defined as normal group and GFR<90 ml/(min·1.73 m 2 ) was defined as reduced group. Univariate analysis was conducted between two groups. Multivariate regression analysis was performed with GFR as dependent variable and adjusted for risk factors such as age, sex, smoking, waist-hip ratio and physical activity. Results: There were 164 subjects in the normal GFR group (45.3%) and 198 in the reduced GFR group (54.7%). Percentage of males in the reduced GFR group, 118 in total, accounting for 59.6%, were significantly higher than in the normal GFR group (73, 44.5%)( P =0.004). The median of age, uric acid, triglyceride, and waist-to-hip ratio (65 years, 323 mmol/L, 1.73 mmol/L, 0.90) were significantly higher in the reduced GFR group than in the normal GFR group (54 years, 277 mmol/L, 1.45 mmol/L, 0.88) ( P< 0.05). The median of PD mean, AL mean, BI mean, PD≥4 mm%, AL≥3 mm%, and AL≥4 mm% in the reduced GFR group were 2.80 mm, 2.52 mm, 2.06, 20.4%, 46.5%, and 30.4%, respectively, which were significantly higher than those in the GFR normal group (2.60 mm, 2.37 mm, 1.93, 16.6%, 42.9%, 28.9%) ( P< 0.05). After adjusting for confounding factors such as age, gender, smoking, waist-to-hip ratio and physical activity, the results of logistic regression analysis showed that PD mean, AL mean, PD≥4 mm%, PD≥5 mm%, PD≥6 mm%, AL≥3 mm% and AL≥4 mm% of clinical periodontal indexes were significantly correlated with reduced GFR in this population ( OR values were 1.765, 1.879, 1.430, 1.713, 1.771, 1.428, 1.445, respectively, P< 0.05). Conclusions: In the non-diabetic elderly population in communities of Shijingshan, Beijing, clinical periodontal indexes reflecting the degree of periodontal tissue destruction were associated with a decreased level of GFR.

Objective: To survey the cigarette smoking status and periodontal status, and to study the correlation between cigarette smoking and periodontal status., Methods: Questionnaires were distributed (including self-assessed periodontal status, such as bleeding while brushing teeth, oral odor, tooth loosening, gum swelling, etc.) and clinical periodontal examinations performed for parameters including probing depth (PD), bleeding index (BI), attachment loss (AL), plaque index (PLI) and amount of teeth loss, which was recorded in the population above 35 years of a community in Beijing. A total of 974 subjects were recruited in the study. The population was divided into current smokers and non-smokers, and the differences of self-assessed periodontal status and periodontal parameters between the groups analyzed., Results: The smokers had significantly less bleeding during toothbrushing, and in the meantime, had significantly more self-reported tooth loosening compared with the non-smokers. The smokers brushed their teeth less than the non-smokers (P<0.05). The self-reported gum swelling and oral odor had no significant difference between the smokers and non-smokers. The smokers had 0.565 times and 1.572 times the risk of bleeding during toothbrushing, self-reported tooth loosening and from Logistic regression analyses, respectively (P<0.05). The mean PD, AL, PLI and the amount of tooth loss of the smokers were significant higher than the non-smokers (P<0.05). However, the mean BI of the smokers was slightly less than the non-smokers' (1.93±0.540 vs. 1.94±0.512, P=0.707). The smokers had 2.129 times, 1.698 times and 1.933 times the risk of the mean PD>3 mm, the mean AL>3 mm, and the amount of tooth loss above 8, respectively compared with the non-smokers (P<0.05) from Logistic regression analyses., Conclusion: The self-assessed periodontal status is different between smokers and non-smokers in the population of a community in Beijing. Smokers have less bleeding during toothbrushing but no significant difference with BI. Smokers also have more self-reported tooth loosening. Compared with non-smokers, smokers have more severe periodontal destruction.