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The sheet-pile wall is widely combined with anchoring frame beam to support high slope in Geotechnical Engineering. However, the dynamic characteristics of the sheet-pile wall with anchoring frame beam subjected to seismic excitation are not clear, and the seismic design for such combined structure is still performed based on pseudo-static method or experience. The combination effect will probably induce an interaction between the sheet-pile wall and the anchoring frame beam, which subsequently makes the seismic behavior of such combined structure more complex. In this study, numerical simulation and shaking table test were carried out to investigate the seismic response of the sheet-pile wall with anchoring frame beam by applying Wenchuan ground motion with different amplitudes. The acceleration response, the earth pressure response and the axial stress of anchor were studied in time domain, and the failure mode of structure was obtained by analyzing the element state at different excitation moment. The influence of the excitation amplitudes on the seismic response of sheet-pile wall with anchoring frame beam was also studied regarding the acceleration amplification, the residual earth pressure, the peak earth pressure response, the distribution of anchor stress and the element state of structure. The results show that the acceleration response of sheet-pile wall with anchoring frame beam is less intense while experiencing another equal seismic excitation. The acceleration amplification of anchoring frame beam is greater than that of sheet-pile wall. The residual earth pressure behind sheet-pile wall increases with an increase in excitation amplitude, especially at the top of sheet-pile wall. The peak earth pressure response at the back of sheet-pile wall increases along the wall height, while it presents a decreasing trend behind anchoring frame beam. The anchor is more likely to fail at the beginning of earthquake. The axial stress of anchor increases nonlinearly with an increase in excitation amplitude, and the increasing ratio increases for a larger value of input acceleration. The outer surface of soil deposit experiences repeated tension and shear failures. The element state of structure changes greatly during the intense periods of seismic excitation.

The combined retaining structure is widely used in high slope supporting engineering. In this paper, shaking table test and numerical simulation are carried out on the seismic response of a combined retaining structure where a gravity wall and an anchoring frame beam are used as a lower structure and an upper structure, respectively. The shaking events of Wenchuan, Da-Rui and Kobe ground motions with different amplitudes are applied in both horizontal and vertical directions. The horizontal and vertical acceleration responses are studied in time domain and frequency domain based on shaking table test, and the results are compared with those obtained from numerical simulation. The axial stress response of anchor and the element state of combined retaining structure subjected to earthquake loading are supplemented and studied by using numerical simulation. Both horizontal and vertical acceleration responses near the bottom of frame beam are significantly magnified, which results in a dramatic increment in acceleration amplification. The acceleration response behind the frame beam is more intensive than that at the back of the gravity wall. The high-frequency component of seismic ground motion is weakened by the combined retaining structure, and the vertical acceleration response presents a wider frequency band. The axial stress of anchor is greatly increased by seismic excitation, and the increment is mainly induced within the excitation period of great acceleration amplitude. Shear failure, tension failure, or both are observed at different positions of combined retaining structure during seismic excitation.

The thermal decomposition of n‐heptane is an important process in petroleum industry. The theoretical investigations show that the main products are C2H4, H2, and C3H6, which agree well with the experimental results. The products populations depend strongly on the temperature. The quantity of ethylene increases quickly as the temperature goes up. The conversion of n‐heptane and the mole fraction of primary products from reactive molecular dynamic and chemical kinetic modeling are compared with each other. We also investigated the pre‐exponential factor and activation energy for thermal decomposition of n‐heptane by kinetic analysis from the reactive force field simulations, which were extracted to be 1.78×1014s−1 and 47.32 kcal/mol respectively.

A series of ( E )-3-benzylidene-4-chromanone derivatives are synthesized, which are substituted with a halogen group on the chromanone moiety in order to control the molecular arrangement in the crystalline state. The stereoselective photoreactions of these compounds in the solid state are examined based on the crystal structures of the reactants and products. All the examples tested undergo photodimerization, except for ( E )-3-benzylidene-6-fluorochroman-4-one. The reactants with β-structures give syn -head-to-head ( syn -HH) products with high selectivity. Only ( E )-6-chloro-3-(4-methylbenzylidene)-chroman-4-one adopted the α-form and gives an anti -head-to-tail ( anti -HT) product.

Halogen substituent plays an important role in the crystalline packing of aromatic compounds. The [2+2] photocycloaddition of (E)-3-benzylidene-4-chromanones in the crystalline state was investigated, and halogen substitution has been adopted to organize molecules with proper arrangement for photodimerization. Not halogen bonds, but the electron-withdrawing property of halogen atoms can enhance the face-to-face π–π interactions. Therefore, F, Cl or Br substitution at the para position of phenyl gave rise to almost the same β-structures with face-to-face π-stacking. Only resulted β-structures can undergo photodimerization, which gave the syn-HH (syn-head-to-head) products with high regio-/stereoselectivity.

A series of novel C3 symmetric tris(thiazoline) ligands were synthesized from trimethyl nitrilotriacetate and an enantiomerically pure amino alcohol via an efficient route. Compound 7a showed moderate to good catalytic enantioselectivity for the asymmetric allylic oxidation of cycloalkenes.

A door-to-door two-phase study was used to investigate the prevalence of senile dementia in an urban community of Beijing. In the study population, 5,003 individuals aged 60 years and older (≥65 years, n = 3,728) were screened at home with the Chinese version of the MMSE. Persons who screened positive for dementia, using different cutoff scores based on degree of literacy, were further evaluated using the criteria of DSM-III-R and ICD-10. Among subjects who screened positive in phase I, 134 were diagnosed as having dementia in phase II. The prevalence ratios of dementia were 2.68% in the population aged 60 years and older, and 3.49% in the population aged 65 years and older. The prevalence rates among those aged 65 years and older were 1.85% for Alzheimer’s disease, 1.37% for vascular dementia and 0.27% for other dementia (including mixed dementia). The prevalence of all dementia and AD increased steeply with advancing age and was consistently higher in women, but it was not obviously higher for VaD in women. Alzheimer’s disease was the commonest type of dementia. Our prevalence figures for dementia and AD are similar to those previously reported for China.

Background and Purpose —Stroke has been the second leading cause of death in large cities in China since the 1980s. Meanwhile, the prevalences of hypertension and smoking have steadily increased over the last 2 decades. Therefore, a community-based intervention trial was initiated in 7 Chinese cities in 1987. The overall goal of the study was to evaluate the effectiveness of an intervention aimed at reducing multiple risk factors for stroke. The primary study objective was to reduce the incidence of stroke by 25% over 3.5 years of intervention. Methods —In May 1987 in each of 7 the cities, 2 geographically separated communities with a registered population of about 10 000 each were selected as either intervention or control communities. In each community, a cohort containing about 2700 subjects (≥35 years old) free of stroke was sampled, and a survey was administered to obtain baseline data and screen the eligible subjects for intervention. In each city, a program of treatment for hypertension, heart disease, and diabetes was instituted in the intervention cohort (n≈2700) and health education was provided to the full intervention community (n≈10 000). A follow-up survey was conducted in 1990. Comparisons of intervention and control cohorts in each city were pooled to yield a single summary. Results —A total of 18 786 subjects were recruited to the intervention cohort and 18 876 to the control cohort from 7 cities. After 3.5 years, 174 new stroke cases had occurred in the intervention cohort and 253 in the control cohort. The 3.5-year cumulative incidence of total stroke was significantly lower in the intervention cohort than the control cohort (0.93% versus 1.34%; RR=0.69; 95% CI, 0.57 to 0.84). The incidence rates of nonfatal and fatal stroke, as well as ischemic and hemorrhagic stroke, were significantly lower in the intervention cohort than the control cohort. The prevalence of hypertension increased by 4.3% in the intervention cohort and by 7.8% in the control cohort. The average systolic and diastolic blood pressures increased more in the control cohort than in the intervention cohort. Among hypertensive individuals in the intervention cohort, awareness of hypertension increased by 6.7% and the percentage of hypertensives who regularly took antihypertensive medication increased 13.2%. All of these indices became worse in the control cohort. The prevalence of heart diseases and diabetes increased significantly in the both cohorts ( P Conclusions —A community-based intervention for stroke reduction is feasible and effective in the cities of China. The reduction, due to the intervention, in the incidence of stroke in the intervention cohort was statistically significant after 3.5 years of intervention. The sharp reduction in the incidence of stroke may be due to the interventions having blunted the expected increase in hypertension that accompanies aging as well as to better and earlier treatment of hypertension, particularly borderline hypertension. Applied health education to all the residents of the community may have prevented some normotensive individuals from developing hypertension and improved overall health awareness and knowledge.

It is well known that agrochemicals have played a important role in agricultural production that provided for about 700 million people during the past 50 years. At the same time, the increasing world population seems to be a major driving force for the need to enhance the output of food production. The agrochemical industry has been very successful in developing new herbicides and other agrochemicals. Herbicides are used widely in the world in protecting crops from undue competition from weeds (Price & Kelton, 2011).

A case control study was conducted to investigate the association of family history of febrile seizures (FS) and history of maternal, pregnancy and delivery, and postnatal factors with FS. Information was gathered by door-to-door survey in six major cities in the People's Republic of China. Factors present before the date of onset of FS were assessed in 182 subjects and in an equal number of controls matched for age, sex, and geographic area. The odds ratio for risk of FS in children with a family history of FS in a first-degree relative was 10.0 (confidence interval 2.7-58.6), confirming other observations that familial factors are an important predisposing characteristic for FS. Maternal acute respiratory infection during the first trimester of pregnancy was slightly more frequent in children with FS (odds ratio, 1.9 confidence interval 1.0-3.9). None of the other examined pregnancy or delivery factors was associated with an increased risk, suggesting that birth history is not an important factor predisposing to FS.

A case-control study on stroke was carried out in 1985 in conjunction with a prevalence survey on neurologic disorders in 22 rural communities of the People's Republic of China. 585 cases of stroke, detected from the survey, together with an equal number of matched controls were investigated. The statistically significant factors associated with stroke in this study were: hypertension (history, findings at examination); high salt intake; family member(s) with cerebrovascular disease and/or hypertension; heart disease (history, abnormal findings at examination); history of transient ischemic attacks, and arteriosclerotic funduscopic findings. These factors were analyzed separately for hemorrhagic and ischemic strokes.

To investigate the effects of hemorrhagic shock and intra-abdominal hypertension (IAH) on inflammatory responses of peripheral circulating neutrophils such as intracellular cytokine production, phagocytic capacity and expression of nuclear factor (NF)- kappaB.Twenty-four rabbits were divided equally into 4 groups including a hemorrhagic shock (HS) group complicated by abdominal compartment syndrome (ACS) (Group A), a HS group (Group B), a ACS group (Group C) and a normal control group (Group D). Intracellular interleukin (IL)-8 production in the peripheral neutrophils were measured in the rabbits by flow cytometry, phagocytic function of the neutrophils evaluated by a chemiluminescence method and the NF-kappaB expression detected by immunocytochemistry before, immediately and 4 h after the traumatization.Four hours after the trauma, decreased intracellular IL-8 production and impaired phagocytic function of the peripheral neutrophils were observed in Group A along with suppressed NF-kappaB expression. But in Group B and Group C, the intracellular IL-8 production, phagocytic function and expression of NF-kappaB returned to the normal levels 4 hours after the trauma following the early-stage changes. In Group D, no significant changes occurred during the observation.Responsiveness and function of the neutrophils to the stimuli by endotoxin are suppressed by the sequential second-hit of IAH after hemorrhagic shock, which may contribute to the occurrence of sepsis in ACS.

To evaluate the community-based intervention on reduction of hypertension and stroke in different age groups and subtypes hypertension.In 6 cities, 2 geographically separated communities with a registered population about 10 000 of each were selected as either intervention or control communities. A cohort containing 2 700 subjects, 35 years or older, and free of stroke were sampled from each community. The baseline survey was conducted to screen the subjects for intervention. In each city, a program for control of hypertension, heart diseases and diabetes was initiated in the intervention cohort and health education was provided to the whole intervention community. A follow-up survey was conducted 3 years later.Within 3 years, the prevalence of hypertension increased in both intervention and control cohorts, as well as in the middle and elderly cohorts, especially in the middle aged in control group. Among hypertensives in the intervention cohort, the rates of awareness, treatment and control of hypertension got improved. The incidence of stroke was 29% lower (HR = 0.71, 95% CI: 0.58 - 0.87) and mortality of stroke was 40% lower (HR = 0.60, 95% CI: 0.42 - 0.86) in the intervention cohort than the control cohort. The intervention was most effective in reduction of stroke for those with isolated systolic hypertension and combined systolic and diastolic hypertension (All P0.05). Meanwhile, all-cause mortality was 11% lower (HR = 0.89, 95% CI: 0.78 - 0.99) in the intervention cohort than in the control cohort.The community-based intervention was effective in controlling the development of hypertension and stroke, while the elderly people benefit more than the middle aged people from the intervention.

As part of a longitudinal study performed in urban China, 37,655 subjects were evaluated for stroke risk factors, including having their blood pressure measured in a standard fashion. The cohort was followed for 3.5 years during which time 427 subjects experienced incident strokes – 221 ischemic, 203 hemorrhagic, and 3 undefined. Both systolic and diastolic blood pressure were significantly related to risk of stroke and stroke type. Associations were stronger for systolic than diastolic blood pressure. These results emphasize the importance of systolic blood pressure, as opposed to diastolic, as a risk factor for stroke. In this study, the risk of stroke is increased by about 25% with each 10 mm Hg increase in systolic blood pressure.

Background and Purpose Incidence of stroke varies markedly in different world populations. In seven Chinese cities, the effect of a program of risk factor modification on the incidence and mortality of stroke was studied and compared with a control population. This article describes the incidence of stroke in the control populations for the years 1986 through 1990. Methods Incidence (first-ever strokes only) for 1986 was obtained by door-to-door interview with heads of households with subsequent verification on examination by a neurologist and review of medical and/or hospital records. In subsequent years, cases were ascertained with a three-tier monitoring system: by community health workers, local medical centers, and the Beijing Neurosurgical Institute. Results Average annual age-adjusted incidence per 100 000 was 215.6 (261.5 for males, 174.5 for females; P P Conclusions The stroke incidence rates in China, like those in Japan, are among the higher ones in the world. In recent years, there has been an apparent decline in stroke incidence. Marked differences in rates were found between males and females with decline in incidence occurring almost exclusively in males. There were also marked differences in stroke incidence among the cities studied. These differences may result in part from differences in diet, alcohol and cigarette consumption, or prevalence of hypertension.

Findings are reported from a collaborative research project on the experience of epilepsy and treatment among patients and family members in Shanxi and Ningxia Provinces in China. Family, marriage, financial and moral consequences of the social experience of epilepsy support the conceptualization of chronic illness as possessing a social course. Beyond traditional concern with stigma, application of concepts of delegitimation, sociosomatic processes, coping as resistance, contestation in the evaluation of efficacy and compliance, and the cultural ontology of suffering illustrate other ways that social theory is useful in research on chronic illness and disability.

Using a case-control method, we studied the role of environmental risk factors and viral infection in the development of Parkinson's disease (PD) in China. Ninety-three PD patients and 186 controls were investigated with a questionnaire and from most of them, blood was taken to test the antibody levels of four virus (measles, rubella, HSV-1, CMV) IgG. The study result showed that positive family history, living near rubber plants, drinking river-water were associated with an increased risk of developing PD. In contrast, living in small cities, drinking well-water, drinking hard-liquor frequently, were associated with a decreased risk for PD. PD cases and controls did not differ with respect to other factors investigated including smoking and viral infection. These findings suggest that some environmental factors may be related to the development of PD, but further standardized studies will be required to confirm our results.

To determine the prevalence of major neurologic disorders, a door-to-door survey was conducted in six cities of the People's Republic of China during 1983 in a well-defined population of 63,195. The survey included a complete census and a screening interview together with an examination having high sensitivity for detecting individuals with frequently occurring neurologic disorders, including epilepsy. All individuals with responses or findings suggesting neurologic disease were examined by senior neurologists using standardized diagnostic criteria. There was 100% cooperation among the study subjects. Two hundred eighty-nine individuals alive on prevalence day (January 1, 1983) were identified as having epilepsy, yielding a lifetime age-adjusted (to the 1960 U.S. population) point prevalence ratio of 4.4/1,000. There were 16 people who developed epilepsy in the sample population during 1982, providing an age-adjusted incidence rate of 35/100,000 per year. The most frequent type identified was generalized convulsive seizures. Brain injury, intracranial infection, and cerebrovascular disease, in that order, were the leading putative causes of epilepsy.

A case-control study was conducted in 1983 on 210 cerebrovascular disease (CVD) patients identified from a retrospective cross-sectional door-to-door survey of four cities in the People's Republic of China. One hundred and eleven male (mean age 63.8 +/- 8.9 years) and 99 female (mean age 63.5 +/- 11.1 years) CVD survivors and controls matched for sex, age, race and area were selected. Total serum cholesterol, high-density lipoprotein and low-density lipoprotein cholesterol were measured to see if there were differences between lipids in survivors of CVD and their matched controls. There was a higher level of total cholesterol in cerebral thrombotic patients (n = 114) and a lower level of total cholesterol and high-density lipoprotein cholesterol in cerebral hemorrhagic patients (n = 35) than in controls, although the results were not statistically significant. The only higher level of total serum cholesterol that might be important was in the group of male thrombotic patients of age greater than 70 years (n = 22; nominal p value less than 0.05). The implication of this finding needs further clarification.

A door-to-door survey was carried out in a well-defined population of Beijing to determine the prevalence and incidence of cerebrovascular disease (CVD) among 10,941 individuals. The survey included a

A door-to-door survey was carried out in six cities of the People's Republic of China (PRC). There was 100% cooperation with the survey. Among 63,195 screened individuals, there were 392 prevalent cases of completed stroke and 115 incidence cases. Prevalence ratios and incidence rates for completed stroke showed a south-to-north gradient. The highest point prevalence ratio and incidence rate (age-adjusted to the 1960 US population) were documented in Harbin in northeast PRC (1,249/100,000; 441/100,000/yr). The majority of new completed strokes were cerebral infarction, but the percentage of intracerebral hemorrhage (44%) was much greater than that reported among Caucasian populations.

Two Chinese populations over age 15 were surveyed as to the point prevalence of “incapacitating” headaches in an urban population of 1, 525 persons and a rural one of 1,203. Personal interviews were carried out by a team of instructed interviewers; there was 100% cooperation. In both populations, prevalence in women was twice that in men except in the urban population in the youngest age group. Prevalence in the urban was almost exactly twice that of the rural population, with the highest figure occurring in traders.

SYNOPSIS The first large scale study of migraine epidemiology from a nationwide collaborative group was carried out in 22 Chinese rural and ethnic minority communities of 21 provinces of the People's Republic of China during 1985 in a well-defined population of 246,812 inhabitants. On the day for which prevalence was calculated, January 1, 1985, there were 1703 cases of migraine, yielding a point prevalence ratio of 690/100,000. The prevalence ratio of migraine for females was higher than that for males. The overall sex difference in the prevalence ratio was significant (Z=26.57, P

• A door-to-door survey was carried out in six cities of the People's Republic of China during 1983 in a well-defined population of 63,195 to determine the prevalence of frequently occurring neurologic disorders, including brain injury. In the survey, trained health workers conducted a complete census and administered a questionnaire that had been pretested to assure a high level of sensitivity in identifying individuals suffering from brain injury due to head trauma. All those with responses suggesting brain injury were examined by senior neurosurgeons who used uniform diagnostic criteria and reviewed available medical records to establish a diagnosis. There was 100% cooperation with the screening and diagnostic phases of the survey. Based on this investigation, the age-adjusted (to the 1960 US population) prevalence ratio for brain injury due to head trauma is seven per 1,000, and the incidence rate is 56 per 100,000 per year. The ratios and rates are higher in male than female subjects. The main cause of brain injury due to head trauma in the People's Republic of China is bicycle accidents.