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To establish a genetic susceptibility assessment model of lung cancer risk potentially associated with polycyclic aromatic hydrocarbon (PAH) inhalation exposure among non-smokers in China, a total of 143 patients with lung adenocarcinoma and 143 cancer-free individuals were recruited. Sixty-eight genetic polymorphisms in 10 pathways related to PAH metabolism and tumorigenesis were selected and examined. It was observed that 3 genetic polymorphisms, along with 10 additional genetic polymorphisms via gene-gene interactions, significantly influenced lung cancer risk potentially associated with PAH inhalation exposure. Most polymorphisms were associated with PAH metabolism. According to the established genetic susceptibility score (GSS), lung cancer risk increased with a rise in the GSS level, thereby indicating a positive dose-response relationship.

A kind of elastic coated abrasives used for polishing large mould surface, such as automobile panel mould, is investigated in this research. Many polishing experiments were finished by using elastic coated abrasives in order to study the effects of grit and workpiece material on surface roughness and machining efficiency. It is concluded that surface roughness is minimum and polishing efficiency is the highest when using 120# abrasives at the same condition, surface roughness is the lowest and polishing efficiency is the highest for AISI 1045 steel in three materials. The difficulty of material removal is different if the textures prior to polishing are different in workpiece surface. Surface texture prior to polishing has effects on surface roughness and polishing efficiency. The research results provide foundation for process planning to achieve good surface roughness and high efficiency in the future research.

A novel design of flat chip-size microchannel heat sink for high power devices cooling is proposed and optimized. The inlet of cooling media is placed in the highest heat flux region, leading the coolest media into the region with the highest temperature directly, and as a result, the overall cooling efficiency is improved. Simultaneously, the collect channel is set and the inlet position is slightly off-center, which achieves a uniform temperature distribution. With the aid of a computational fluid dynamics (CFD) method, the temperature distribution of microchannel heat sink under steady-state conditions is examined and the microchannel distribution is optimized, forming an optimal design for the chip-size microchannel heat sink.

The electrical characteristic of MOS device is susceptible to the external mechanical stress. In order to investigate the effect, the four-point bending technique has been used by many researchers to apply stress on the device. In this paper, a new way for applying stress to MOS device has been presented. The stress is applied by a metallic film which is deposited on the backside of the chip. Its convenient to apply different stress to each chip on the wafer. The above method is used to study the influence of stress on the performance of VDMOS device. The results show that the on-resistance decreases about 3% and 8% with the compressive stress of 50MPa and 70MPa respectively.

A compliant abrasive tool is investigated in this paper. By the polishing experiment of this abrasive tool, the technique of polishing the large mould free-form surface is acquired. The polishing experiments about the elastic abrasive tool are carried out, which indicates that the abrasive tool has the advantages of the high efficiency, the elasticity and compliant performance. The relation of the deflection and polishing force is investigated and it is concluded that they is approximately linearity. The effect of polishing pressure on the surface roughness is researched by experiment. Polishing quality for the edge of abrasive tool was investigated and presented. These experiment results provide significant foundation for planning polishing path and controlling process parameters to achieve good surface roughness and high efficiency in the next research.

In order to solve spring-back problem of the stamping forming process, A method for stamping forming and spring-back process simulation of automotive panel by finite element technologies was proposed. The solid model of automobile right side strengthening panel was created in UG software and transmitted to Dynaform. The stamping forming and spring-back process simulation were realized by using Dynaform. The distribution of strain, the variety of the sheet thickness and the spring-back were analyzed. The maximum stress or strain, the minimum thickness and the maximum spring-back were obtained. The simulation results can reflect the real stamping forming of the strengthening panel, and forecast the possibly spring-back value in stamping process. This research can optimize the stamping process and provide strong references for the design of the automotive panel die.

An elevated serum lipid is one of the major risk factors for coronary heart disease (CHD). Physicians' awareness contributes to successful adoption of practice guidelines. Community medical centers are the primary defense against chronic disease. This study aimed to investigate community physicians' awareness of cholesterol guidelines and their utilization.Six hundred and one community physicians were randomly selected from four different regions, and completed a confidential and semi-structured questionnaire. Four hundred and ninety-one completed the questionnaire, and 486 valid questionnaires were available.The physicians' fundamental knowledge of lipids was astonishingly poor, while the awareness of cholesterol guidelines was low. Only 24% and 14% of the physicians reported the right optimal low-density lipoprotein cholesterol (LDL-C) level for CHD and diabetes patients respectively. More than half of the physicians (55.8%) mistakenly considered elevated transaminases to be the lethal side effect of statins. More than half of the physicians (51.9%) would give up statin treatment in the case of transaminase elevation.Educational interventions to improve cholesterol knowledge and to publicize standard treatment are needed among Chinese community physicians.

To investigate the prevalence of dyslipidemia and borderline dyslipidemia and other coronary heart disease (CHD) risk factors in residents from Beijing communities.Resident samples were selected by random cluster multistage method. Serum lipid level and CHD factors were obtained through questionnaire, physical examination and biochemical analysis during June 2007 to August 2007 from 10 054 residents.Age- and sex-adjusted standardized prevalence of hypercholesterolemia, high low-density lipoprotein cholesterolemia, low high-density lipoprotein cholesterolemia, and triglyceridemia were 9.3%, 2.56%, 18.79% and 16.84%, respectively. Incidence of borderline hypercholesterolemia was 23.96%. Incidence of dyslipidemia and borderline dyslipidemia was 31.23% and 23.30% respectively, 71.17% residents have at least 1 CHD major risk factor and 20.23% residents were in borderline CHD risks. Prevalence of hypertension, diabetes, smoking and obese was 41.57%, 11.08%, 35.81% and 22.89%, respectively. The odds ratio for dyslipidemia (95% confidence interval) in residents having 1 borderline CHD risk factor (RF), 2 RF, and 3 RF versus none RF was 1.668, (95%CI: 1.319 - 2.110), 2.537 (95%CI: 1.989 - 3.235), and 3.203 (95%CI: 2.007 - 5.114).The prevalence of dyslipidemia of residents from Beijing communities is higher the average level of China (25.1%). Over 1 out of 5 residents were in increased risk for borderline dyslipidemia or CHD risks. Intensive control of dyslipidemia and CHD risk factors are warranted in Beijing residents.

To study the difference in prevalence of major risk factors of coronary heart disease (CHD) in resident from Beijing communities in different age groups so as to offer suggestions for prevention of CHD in Beijing.The samples were selected by random cluster multistage method. Serum lipid level and CHD factors were determined through questionnaire, physical examination and biochemical detection for 10 054 subjects in Beijing communities during June 2007 to August 2007. According to age, the subjects were divided into 3 groups: 20 - 44 yr group, 45 - 59 yr group andor = 60 yr group.After age and sex standardization the prevalence of hypercholesterolemia, hypertension, diabetes, smoking and obesity was 9.30%, 41.57%, 10.18%, 35.81% and 22.89% respectively. The prevalence of hypercholesterolemia, hypertension and diabetes showed an rising trend with advancing age (trend chi(2): 15.6, 31.7 and 18.0, all P0.001). The group of 45 - 59 yr had the highest prevalence in smoking and obesity 28% and 25.27% respectively. Over 30% in the groups of 45 - 59 yr andor = 60 yr were in the borderline of hypercholesterolemia and hypertension and over 40% were overweight. After age and sex standardization, 67.15% of community residents had at least 1 CHD risk factor, 21.37% and 8.50% 2 or over 3 CHD risk factors. As compared with group 20 - 44 yr, the odds ratio (95%CI) for clustering of CHD risk factors in groups 45 - 59 yr andor = 60 yr were 2.63 (95%CI 2.371 - 2.924) and 4.3 (95%CI 3.764 - 4.913) respectively. The odds ratio (95%CI) for clustering of CHD risk factors for male vs female was 4.392 (95%CI 3.938 - 4.899).The prevalence of CHD major risk factors of Beijing community residents is high. Groups of 45 - 59 yr andor = 60 yr have a higher prevalence and clustering of CHD major risk factors than 20 - 44 yr group. So these age groups deserve a higher priority of comprehensive prevention and control strategies of CHD.

To evaluate the abstinence rate and relapse rate of smoker with ACS after discharged from hospital, to evaluate the effect of simple smoking cessation interventions.150 smokers with ACS were collected and was divided into simple intervention group (n = 87) and control group (n = 63), respectively, followed up for 6 months. 2 months, 6 months abstinence rate, relapse rate were compared between two groups, logistic regression model was used to analyzed the relevant factors for relapse.The smoking rate in patients with ACS was 31.14%, 6-month continuous abstinence rate and 6-month relapse rate was 64.6%, 36.4%, respectively. 6-month continuous abstinence rate and relapse rate between simple quit-smoking intervention group and control group showed no difference. Nicotine dependence score more than 4 points can be used as predictor of relapse.The smoking rate and the abstinence rate of smoker with ACS is higher than the general population, simple quit-smoking intervention do not increase the success rate of quit-smoking, indicated the need to strengthen the intervention in patients with ACS and smoking.

To compare the prognostic value of B-type natriuretic peptide (BNP) and GRACE score in patients with acute coronary syndrome.A total of 246 patients with chest pain to hospital time24 hours were followed up to 30 days. Admission plasma B-type natriuretic peptide was measured by point-of-care. Endpoints included death, reinfarction, recurrent ischemia and new onset of congestive heart failure. The receiver operating characteristic (ROC) curve was used to evaluate prognostic value of BNP and GRACE score. The logistic regression models were used to assess the prognostic contribution of BNP level and GRACE score.The mean age was (67.6 +/- 12.0) years (61.8% males) and ST elevation myocardial infarction (STEMI) was diagnosed in 135 patients (54.9%). During the follow up, 34 endpoints (13.8%) were recorded including 9 deaths (3.7%). The systolic blood pressure [(121 +/- 29) mm Hg vs. (130 +/- 23) mm Hg, P = 0.034; 1 mm Hg = 0.133 kPa] was significantly lower while the heart rate and plasma creatinine were significantly higher in the endpoints group than in non-endpoints group. TNI and CRP levels were similar between the two groups. The BNP level at admission (median 883.5 ng/L vs. 216.5 ng/L) and GRACE score (median 164.5 vs. 142.0) were significantly higher in the endpoints group than in non-endpoints group (all P0.05). The prognostic criteria for BNP level (area under cure, 0.704) was 194.5 ng/L determined by ROC (P = 0.043). For GRACE score, the predictive value for endpoints was 0.742 (P = 0.003) and the cut-off point was 158. In the logistic regression model, BNP concentration (194.5 ng/L, OR = 3.174) and GRACE score (158, OR = 4.031) were independent predictors of endpoints in patients with ACS.Both BNP level at admission and GRACE score were independent predictors for endpoints at 30 days in patients with ACS.

Criteria of obesity in the Chinese population with multiple metabolic risk factors remains unclear. The objective was to determine the best anthropometrical measurements with regard to the metabolic syndrome (MetS) and to propose optimal cut-off values. Between April and August, 2007, 3,704 men and 6,392 women aged 18-85 years were recruited from four community centers. Medical examinations included measurement of weight, height, waist circumference (WC), hip circumference, fasting blood triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), glucose concentrations, and blood pressure (BP). Body mass index (BMI), waist to hip ratio (WHR), WC and waist to stature ratio (WSR) were calculated. Four metabolic risk factors were examined: 1) high BP; 2) high levels of TG; 3) low levels of HDL-C; 4) impaired glucose tolerance. The relationships between studied indices and risk factors were analyzed using partial correlation analyses, analysis of variance (ANOVA), linear regression, and Receiver Operator Characteristic (ROC) curve analysis. The optimal cut-off values of each obesity index were calculated using ROC analysis respectively. All obesity indices were positively associated with metabolic risk factors. Area under curve (AUC) of WC was the largest foror= 2 risk factors after adjustment for age in both genders. Optimal cut-off points for WC were 89 cm in men, and 80.5cm, 82.5cm, and 89.5cm in40-yr, 40-60-yr, and60-yr women respectively. Waist circumference is best associated with metabolic risk factors among the studied indices in Chinese adults. Indices of abdominal obesity for older age groups tend to be higher than younger age groups in women.