As a component of the process of rationalization, lowcost housing Institution, as well as major investiment companies, commonly reuse a typical design as a standard. The goal of this procedure is to obtain cheaper cos...As a component of the process of rationalization, lowcost housing Institution, as well as major investiment companies, commonly reuse a typical design as a standard. The goal of this procedure is to obtain cheaper costs both in the construction and in the maintenance of an homogeneous lot of buildings. The paper shows that, nevertheless an identical design being proposed in different towns, the final results are buildings with a different aspect. This is mainly due to the influence of building codes of the urban plan of the specific town, and to the site conditions, such as street orientation, ground inclination and so on. As a result the paper offers the ability to evaluate the role of the external factors on a standard design (with the afore said scale vantages) under the criminological point of view as well. This may be considered a further vantage that aims to obtain a lower crime risk level in town design.展开更多
AIM:To detect the impact of insulin-like growth factor-1(IGF-1)and other risk factors for the early prediction of retinopathy of prematurity(ROP)and to establish a scoring system for ROP prediction by using clini...AIM:To detect the impact of insulin-like growth factor-1(IGF-1)and other risk factors for the early prediction of retinopathy of prematurity(ROP)and to establish a scoring system for ROP prediction by using clinical criteria and serum IGF-1 levels.METHODS:The study was conducted with 127 preterm infants.IGF-1 levels in the 1st day of life,1st,2nd,3rd and4th week of life was analyzed.The score was established after logistic regression analysis,considering the impact of each variable on the occurrences of any stage ROP.A validation cohort containing 107 preterm infants was included in the study and the predictive ability of ROP score was calculated.RESULTS:Birth weights(BW),gestational weeks(GW)and the prevalence of breast milk consumption were lower,respiratory distress syndrome(RDS),bronchopulmonarydysplasia(BPD)and necrotizing enterocolitis(NEC)were more frequent,the duration of mechanical ventilation and oxygen supplementation was longer in patients with ROP(P〈0.05).Initial serum IGF-1 levels tended to be lower in newborns who developed ROP.Logistic regression analysis revealed that low BW(〈1250 g),presence of intraventricular hemorrhage(IVH)and formula feeding increased the risk of ROP.Afterwards,the scoring system was validated on 107 infants.The negative predictive values of a score less than 4 were 84.3%,74.7%and 79.8%while positive predictive values were 76.3%,65.5%and71.6%respectively.CONCLUSION:In addition to BW〈1250 g and IVH,formula consumption was detected as a risk factor for the development of ROP.Breastfeeding is important for prevention of ROP in preterm infants.展开更多
Objectives Mu Lao Zu population.Methods A total of 1055 subjects of Mu Lao Zu were studied by a stratified randomized cluster sampling.Blood pressure,body height, body weight,waist circumference and serum lipid and ap...Objectives Mu Lao Zu population.Methods A total of 1055 subjects of Mu Lao Zu were studied by a stratified randomized cluster sampling.Blood pressure,body height, body weight,waist circumference and serum lipid and apolipoprotein(Apo) levels were measured.The data were compared with those in 969 subjects of Han Chinese from the same region.In order to evaluate the association of hyperlipidemia with nine possible riks factors,multivariate logistic regression analysis was also performed in the combined population of Mu Lao Zu and Han,Mu Lao Zu,and Han;respectively. Results The levels of total cholesterol,triglyceride, low-density lipoprotein cholesterol and ApoB in Mu Lao Zu were significantly higher than those in Han(P【0.05-0.001); but the levels of high-density lipoprotein cholesterol,ApoA1 and ApoA1/Apo were significantly lower than those in Han (P【0.001 ).The prevalence of hyperlipidemia and Hypercholesterolemia was also significantly higher in Mu Lao Zu than in Han(53.0%vs.46.1%,P【0.001) and(44.5%vs. 37.5%,P【0.001).There was no difference in the prevalence of hypertriglyceridemia between the both ethnic groups (22.8%vs.19.4%,P】0.05).Hyperlipidemia was positively correlated with age,BMI,and systolic blood pressureMu Lao Zu(P【0.05),whereas it was positively correlated with BMI and hypertension in Han(P【0.05 for each).Conclusions The serum lipid profiles,the prevalence of hyperlipidemia and the risk factors are different between the Mu Lao Zu and Han populations.The differences in serum lipid profiles between the two ethnic groups might result from different dietary habit,life style,as well as genetic factors,in ? To determine the serum lipid levels and their risk factors in the Guangxi.展开更多
The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multi...The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multienergy complementary ways.Focusing on the regional integrated energy system composed of electrical microgrid and natural gas network,a fault risk warning method based on the improved RelieF-softmax method is proposed in this paper.The raw data-set was first clustered by the K-maxmin method to improve the preference of the random sampling process in the RelieF algorithm,and thereby achieved a hierarchical and non-repeated sampling.Then,the improved RelieF algorithm is used to identify the feature vectors,calculate the feature weights,and select the preferred feature subset according to the initially set threshold.In addition,a correlation coefficient method is applied to reduce the feature subset,and further eliminate the redundant feature vectors to obtain the optimal feature subset.Finally,the softmax classifier is used to obtain the early warnings of the integrated energy system.Case studies are conducted on an integrated energy system in the south of China to demonstrate the accuracy of fault risk warning method proposed in this paper.展开更多
The Three Gorges region in China was basically a geohazard-prone area prior to construction of the Three Gorges Reservoir (TGR). After construction of the TGR, the water level was raised from 70 m to 175 m above sea...The Three Gorges region in China was basically a geohazard-prone area prior to construction of the Three Gorges Reservoir (TGR). After construction of the TGR, the water level was raised from 70 m to 175 m above sea level (ASL), and annual reservoir regulation has caused a 30-m water level difference after impoundment of the TGR since September 2008. This paper first presents the spatiotemporal distribution of landslides in six periods of 175 m ASL trial impoundments from 2008 to 2014. The results show that the number of landslides sharply decreased from 273 at the initial stage to less than ten at the second stage of impoundment. Based on this, the reservoir-induced landslides in the TGR region can be roughly classified into five failure patterns, i.e. accumulation landslide, dip-slope landslide, reversed bedding landslide, rockfall, and karst breccia landslide. The accumulation landslides and dip-slope landslides account for more than 90%. Taking the Shuping accumulation landslide (a sliding mass volume of 20.7 × 106 m^3) in Zigui County and the Outang dip-slope landslide (a sliding mass volume of about 90 × 106 m^3) in Fengjie County as two typical cases, the mechanisms of reactivation of the two landslides are analyzed. The monitoring data and factor of safety (FOS) calculation show that the accumulation landslide is dominated by water level variation in the reservoir as most part of the mass body is under 175 m ASL, and the dip-slope landslide is controlled by the coupling effect of reservoir water level variation and precipitation as an extensive recharge area of rainfall from the rear and the front mass is below 175 m ASL. The characteristics of landslide-induced impulsive wave hazards after and before reservoir impoundment are studied, and the probability of occurrence of a landslide-induced impulsive wave hazard has increased in the reservoir region. Simulation results of the Ganjingzi landslide in Wushan County indicate the strong relationship between landslide-induced surge and water variation with high potential risk to shipping and residential areas. Regarding reservoir regulation in TGR when using a single index, i.e. 1-d water level variation, water resources are not well utilized, and there is also potential risk of disasters since 2008. In addition, various indices such as 1-d, 5-d, and 10-d water level variations are proposed for reservoir regulation. Finally, taking reservoir-induced landslides in June 2015 for example, the feasibility of the optimizing indices of water level variations is verified.展开更多
In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 a...In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 articles met our inclusion criteria. The overall geometric mean (GM) BLL was 71 μg/L, and the prevalence of elevated BLL (EBLL, defined as BLL ≥100 μg/L) was 18.48% among children. The prevalence of EBLL remained significantly higher among boys. In children less than 6 years of age, there were significantly increasing trends in both BLL and prevalence of EBLL in an age-dependent manner. The ban on leaded gasoline significantly reduced the BLL as well as EBLL prevalence; however, children whose parents had lower educational levels or were exposed to lead in the workplace had a higher EBLL prevalence. Despite its decline over time, the average BLL among children in China remains higher than the average level most recently reported in the United States. Childhood lead poisoning remains a public health problem in China.展开更多
To the Editor:We read with great interest the article by Yang et al.[1]evaluating the effects of postoperative serum total cholesterol(s TC)changes on early allograft dysfunction and survival after living donor liver ...To the Editor:We read with great interest the article by Yang et al.[1]evaluating the effects of postoperative serum total cholesterol(s TC)changes on early allograft dysfunction and survival after living donor liver transplantation(LDLT).By the multivariate regression analysis,they showed that patients with s TC<1.42 mmol/L on postoperative day 3 had 4.08-fold and 2.72-fold greater risks of展开更多
Purpose–The smoothness of the high-speed railway(HSR)on the bridge may exceed the allowable standard when an earthquake causes vibrations for HSR bridges,which may threaten the safety of running trains.Indeed,few stu...Purpose–The smoothness of the high-speed railway(HSR)on the bridge may exceed the allowable standard when an earthquake causes vibrations for HSR bridges,which may threaten the safety of running trains.Indeed,few studies have evaluated the exceeding probability of rail displacement exceeding the allowable standard.The purposes of this article are to provide a method for investigating the exceeding probability of the rail displacement of HSRs under seismic excitation and to calculate the exceeding probability.Design/methodology/approach–In order to investigate the exceeding probability of the rail displacement under different seismic excitations,the workflow of analyzing the smoothness of the rail based on incremental dynamic analysis(IDA)is proposed,and the intensity measure and limit state for the exceeding probability analysis of HSRs are defined.Then a finite element model(FEM)of an assumed HSR track-bridge system is constructed,which comprises a five-span simply-supported girder bridge supporting a finite length CRTS II ballastless track.Under different seismic excitations,the seismic displacement response of the rail is calculated;the character of the rail displacement is analyzed;and the exceeding probability of the rail vertical displacement exceeding the allowable standard(2mm)is investigated.Findings–The results show that:(1)The bridge-abutment joint position may form a step-like under seismic excitation,threatening the running safety of high-speed trains under seismic excitations,and the rail displacements at mid-span positions are bigger than that at other positions on the bridge.(2)The exceeding probability of rail displacement is up to about 44%when PGA 50.01g,which is the level-five risk probability and can be described as’very likely to happen’.(3)The exceeding probability of the rail at the mid-span positions is bigger than that above other positions of the bridge,and the mid-span positions of the track-bridge system above the bridge may be the most hazardous area for the running safety of trains under seismic excitation when high-speed trains run on bridges.Originality/value–The work extends the seismic hazardous analysis of HSRs and would lead to a better understanding of the exceeding probability for the rail of HSRs under seismic excitations and better references for the alert of the HSR operation.展开更多
The present work aims to identify flood hazards and risks, particularly to the Attanagalu Oya river basin in Gampaha district, the western province in Sri Lanka. Attanagalu Oya river catchment area periodically faced ...The present work aims to identify flood hazards and risks, particularly to the Attanagalu Oya river basin in Gampaha district, the western province in Sri Lanka. Attanagalu Oya river catchment area periodically faced flood hazards. The flood is categorized by complex like 2008, 2010, 2016, 2017, and it chose 2016 as the primary flood event. Study areas have been selected depending on data availability. Attanagalu Oya river basin is mainly focused as a study area. However, here selected only four Grama Niladhari Divisions are as a sample area. Those are;Kirindivita, Ambanvita, Thammita West, Gonagaha1. Furthermore, many flood hazards can be identified when considering the flood events history. But here selected only two years were 2010 and 2016. These two years were selected with high flood events. For the study, that flood series used 1 feet elevation contours used to identify flood levels and used LiDAR image to identify risk areas in the study site. Due to the blockage of the main waterways that discharge water into the Negombo Lagoon, limited water transportation, low lying land reclamation for development, mainly affect paddy lands and roads, and flood as a major problem identified temporarily and spatially. Eventually, the study could identify flood-prone areas and map the risk zones within the study area.展开更多
This work describes the development,optimisation and validation of an analytical method for the rapid determination of 17 priority pharmaceutical compounds and endocrine disrupting chemicals(EDCs).Rather than studying...This work describes the development,optimisation and validation of an analytical method for the rapid determination of 17 priority pharmaceutical compounds and endocrine disrupting chemicals(EDCs).Rather than studying compounds from the same therapeutic class,the analyses aimed to determine target compounds with the highest risk potential(with particular regard to Scotland),providing a tool for further monitoring in different water matrices.Prioritisation was based on a systematic environmental risk assessment approach,using consumption data;wastewater treatment removal efficiency;environmental occurrence;toxicological effects;and pre-existing regulatory indicators.This process highlighted 17 compounds across various therapeutic classes,which were then quantified,at environmentally relevant concentrations,by a single analytical methodology.Analytical determination was achieved using a single-step solid phase extraction(SPE)procedure followed by high-performance liquid chromatography with tandem mass spectrometry(HPLC-MS/MS).The fully optimised method performed well for the majority of target compounds,with recoveries>71%for 15 of 17 analytes.The limits of quantification for most target analytes(14 of 17)ranged from 0.07 ng/L to 1.88 ng/L in river waters.The utility of this method was then demonstrated using real water samples associated with a rural hospital/setting.Eight compounds were targeted and detected,with the highest levels found for the analgesic,paracetamol(at up to 105,910 ng/L in the hospital discharge).This method offers a robust tool to monitor high priority pharmaceutical and EDC levels in various aqueous sample matrices.展开更多
Ambient benzene homologues were measured at a site in the northeastern urban area of Beijing, China, from August 24 to September 4, 2012 by SUMMA canister sampling followed by laboratory determination using cryogenic ...Ambient benzene homologues were measured at a site in the northeastern urban area of Beijing, China, from August 24 to September 4, 2012 by SUMMA canister sampling followed by laboratory determination using cryogenic cold trap pre-concentration-GC-MS/FID, and their health risks were also assessed. Daily total benzene homologues ranged from 0.99 to 49.71 μg/m3 with an average of 11.98 μg/m3. Benzene homologues showed higher concentrations in the morning and evening than that at noontime. Comparison with previous studies revealed a trend of decrease for ambient benzene homologues probably due to the effective emission control in Beijing in recent years. Vehicular exhaust was the main source while volatilization of paints and solvents also made substantial contributions. Health risk assessment showed that BTEX (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) and styrene had no appreciable adverse non-cancer health risks for the exposed population, while benzene has potential cancer risk of 1.34E-05. Available data from cities in China all implied that benzene imposes relatively higher cancer risk on the exposed populations and therefore strict control measures should be taken to further lower ambient benzene levels in China.展开更多
Deficiency of the Preventive Erosion Capacity (PEC) of a bridge pier is the main factor leading to bridge fai lures. In this paper, the PEC of bridge piers was analyzed using the stochastic analysis method. The defi...Deficiency of the Preventive Erosion Capacity (PEC) of a bridge pier is the main factor leading to bridge fai lures. In this paper, the PEC of bridge piers was analyzed using the stochastic analysis method. The definitions of the reliability and risk level of a bridge p ier subjected to water erosion were proposed and a computational model for erosi on depth and risk level in was suggested.展开更多
According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was d...According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was developed using principles from complex network theory.The vulnerability and risk level of each edge in this model were calculated,and high-risk edges and disaster chains were identified.The analysis reveals that the edge“floods→building collapses”has the highest vulnerability.Implementing measures to mitigate this edge is crucial for delaying the spread of secondary disasters.The highest risk is associated with the edge“building collapses→casualties,”and increased risks are also identified for chains such as“earthquake→building collapses→casualties,”“earthquake→landslides and debris flows→dammed lakes,”and“dammed lakes→floods→building collapses.”Following an earthquake,the prompt implementation of measures is crucial to effectively disrupt these chains and minimize the damage from secondary disasters.展开更多
Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.I...Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.In this regard,the research proposes to construct the correlation between climatic design conditions and indoor thermal environment risk level,and explore the effect of uncertainty in building thermal performance on this correlation from the perspective of probability,thus realizing the process of selecting the climatic design conditions based on the requirement for indoor thermal environment risk level.Taking Guangzhou in China as an example,the new process of determining climatic design conditions is realized.On this basis,the difference between the traditional method and the present research method is compared.In the Chinese norm method,the indoor thermal environ-ment risk level of the building is between 0 and 0.03%when the climatic design conditions are selected with 0.57%cumulative frequency of occurrence;in the research method,the indoor thermal environment risk level of the building is between 0.2%and 0.6%when the climatic design conditions are selected with 0.57%indoor thermal environment risk level and 100%confidence level.The results indicate that the research method can meet the designer’s expectation for indoor thermal environment risk level in design more directly and accurately.展开更多
This report addresses the role of radiation dose rate effects on stochastic risks for low linear energy transfer (LET) radiation .The chernobyl nuclear power
Abstract Objectives To investigate the relationship between the β-fibrinogen gene -455A/G polymorphism and plasma fibrinogen level and to determine the influence of the mutation on ischemic stroke. Methods Ninety-o...Abstract Objectives To investigate the relationship between the β-fibrinogen gene -455A/G polymorphism and plasma fibrinogen level and to determine the influence of the mutation on ischemic stroke. Methods Ninety-one patients (63.5±10.1 years) with ischemic stroke and 74 elderly control subjects (60.6±10.8 years) without any thromboembolic events and 98 healthy blood donators as young control (37.5±13.3 years) were enrolled in this trial. The β-fibrinogen gene -455A/G polymorphism was analyzed for all subjects by PCR-RFLP with the restrictive enzyme Hae Ⅲ, while plasma fibrinogen levels were obtained from the prothrombin time (PT) assay. For statistical analysis, the parameters were compared between any two different groups by the unpaired Student’s t test and the Chi-square test. Before analysis, log transformations for concentrations of fibrinogen were carried out.Results H2 allele frequency was higher in male ischemic stroke patients than in the elderly control (22.7% vs 7.1%, χ 2=5.56, P【0.02). There was no significant difference between the female groups. In those patients without any thromboembolic events (both elderly and young control groups), the frequency of H2 decreased with age (≤40, 21.3%; 41-59, 15.4%; and ≥60, 10.2%). In the male elderly and young control groups, the level of plasma fibrinogen was lower in the H1H1 genotype (287±96*!mg/dl and 234±58*!mg/dl) than in H1H2 and H2H2 (331±44*!mg/dl and 307±55*!mg/dl; t=2.53 and 9.67, P【0.05). In the female elderly groups, this tendency was not found.Conclusion Plasma fibrinogen expression is affected by the β-fibrinogen gene -455A/G polymorphism, and the H2 allele may be a risk factor for ischemic stroke in Chinese males.展开更多
As a global pollutant, high levels of mercury(Hg) have been found in remote ecosystem due to the long range atmospheric transport. In this study, a total of 60 fish samples were collected from four rivers across the...As a global pollutant, high levels of mercury(Hg) have been found in remote ecosystem due to the long range atmospheric transport. In this study, a total of 60 fish samples were collected from four rivers across the Tibetan Plateau to study the accumulation of Hg in remote and high-altitude aquatic environment. The total Hg(THg) and methylmercury(MeHg) in fish muscles ranged from 11 to 2097 ng/g dry weight(dw)(average: 819 ng/g dw)and from 14 to 1960 ng/g dw(average: 756 ng/g dw), respectively. Significantly positive linear relationships were observed between the THg(r = 0.591, p 〈 0.01, n = 36) and MeHg concentrations(r = 0.473, p 〈 0.01, n = 36) with the trophic level of fish from Lhasa River,suggesting trophic transfer and biomagnification of Hg in this aquatic ecosystem. Moreover,the THg levels in fish had significantly positive correlations with the length(r = 0.316,p 〈 0.05, n = 60) and weight(r = 0.271, p 〈 0.05, n = 60) of fish. The high levels of Hg were attributed to the slow growth and long lifespan of the fish under this sterile and cold environment. Risk assessment revealed that the consumption of Oxygymnocypris stewartii,Schizothorax macropogon, Schizothorax waltoni, Schizopygopsis younghusbandi and Schizothorax o'connori would lead to a high exposure to Me Hg.展开更多
文摘As a component of the process of rationalization, lowcost housing Institution, as well as major investiment companies, commonly reuse a typical design as a standard. The goal of this procedure is to obtain cheaper costs both in the construction and in the maintenance of an homogeneous lot of buildings. The paper shows that, nevertheless an identical design being proposed in different towns, the final results are buildings with a different aspect. This is mainly due to the influence of building codes of the urban plan of the specific town, and to the site conditions, such as street orientation, ground inclination and so on. As a result the paper offers the ability to evaluate the role of the external factors on a standard design (with the afore said scale vantages) under the criminological point of view as well. This may be considered a further vantage that aims to obtain a lower crime risk level in town design.
文摘AIM:To detect the impact of insulin-like growth factor-1(IGF-1)and other risk factors for the early prediction of retinopathy of prematurity(ROP)and to establish a scoring system for ROP prediction by using clinical criteria and serum IGF-1 levels.METHODS:The study was conducted with 127 preterm infants.IGF-1 levels in the 1st day of life,1st,2nd,3rd and4th week of life was analyzed.The score was established after logistic regression analysis,considering the impact of each variable on the occurrences of any stage ROP.A validation cohort containing 107 preterm infants was included in the study and the predictive ability of ROP score was calculated.RESULTS:Birth weights(BW),gestational weeks(GW)and the prevalence of breast milk consumption were lower,respiratory distress syndrome(RDS),bronchopulmonarydysplasia(BPD)and necrotizing enterocolitis(NEC)were more frequent,the duration of mechanical ventilation and oxygen supplementation was longer in patients with ROP(P〈0.05).Initial serum IGF-1 levels tended to be lower in newborns who developed ROP.Logistic regression analysis revealed that low BW(〈1250 g),presence of intraventricular hemorrhage(IVH)and formula feeding increased the risk of ROP.Afterwards,the scoring system was validated on 107 infants.The negative predictive values of a score less than 4 were 84.3%,74.7%and 79.8%while positive predictive values were 76.3%,65.5%and71.6%respectively.CONCLUSION:In addition to BW〈1250 g and IVH,formula consumption was detected as a risk factor for the development of ROP.Breastfeeding is important for prevention of ROP in preterm infants.
文摘Objectives Mu Lao Zu population.Methods A total of 1055 subjects of Mu Lao Zu were studied by a stratified randomized cluster sampling.Blood pressure,body height, body weight,waist circumference and serum lipid and apolipoprotein(Apo) levels were measured.The data were compared with those in 969 subjects of Han Chinese from the same region.In order to evaluate the association of hyperlipidemia with nine possible riks factors,multivariate logistic regression analysis was also performed in the combined population of Mu Lao Zu and Han,Mu Lao Zu,and Han;respectively. Results The levels of total cholesterol,triglyceride, low-density lipoprotein cholesterol and ApoB in Mu Lao Zu were significantly higher than those in Han(P【0.05-0.001); but the levels of high-density lipoprotein cholesterol,ApoA1 and ApoA1/Apo were significantly lower than those in Han (P【0.001 ).The prevalence of hyperlipidemia and Hypercholesterolemia was also significantly higher in Mu Lao Zu than in Han(53.0%vs.46.1%,P【0.001) and(44.5%vs. 37.5%,P【0.001).There was no difference in the prevalence of hypertriglyceridemia between the both ethnic groups (22.8%vs.19.4%,P】0.05).Hyperlipidemia was positively correlated with age,BMI,and systolic blood pressureMu Lao Zu(P【0.05),whereas it was positively correlated with BMI and hypertension in Han(P【0.05 for each).Conclusions The serum lipid profiles,the prevalence of hyperlipidemia and the risk factors are different between the Mu Lao Zu and Han populations.The differences in serum lipid profiles between the two ethnic groups might result from different dietary habit,life style,as well as genetic factors,in ? To determine the serum lipid levels and their risk factors in the Guangxi.
基金Supported by National Natural Science Foundation of China(No.51777193).
文摘The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multienergy complementary ways.Focusing on the regional integrated energy system composed of electrical microgrid and natural gas network,a fault risk warning method based on the improved RelieF-softmax method is proposed in this paper.The raw data-set was first clustered by the K-maxmin method to improve the preference of the random sampling process in the RelieF algorithm,and thereby achieved a hierarchical and non-repeated sampling.Then,the improved RelieF algorithm is used to identify the feature vectors,calculate the feature weights,and select the preferred feature subset according to the initially set threshold.In addition,a correlation coefficient method is applied to reduce the feature subset,and further eliminate the redundant feature vectors to obtain the optimal feature subset.Finally,the softmax classifier is used to obtain the early warnings of the integrated energy system.Case studies are conducted on an integrated energy system in the south of China to demonstrate the accuracy of fault risk warning method proposed in this paper.
基金The"Twelfth Five-Year Plan"of the National Science and Technology Support Project(Grant No.2012BAK10B01)the National Natural Science Foundation of China(Grant Nos.41372321 and 41502305)China Geological Survey Projects(Grant No.121201009000150018)
文摘The Three Gorges region in China was basically a geohazard-prone area prior to construction of the Three Gorges Reservoir (TGR). After construction of the TGR, the water level was raised from 70 m to 175 m above sea level (ASL), and annual reservoir regulation has caused a 30-m water level difference after impoundment of the TGR since September 2008. This paper first presents the spatiotemporal distribution of landslides in six periods of 175 m ASL trial impoundments from 2008 to 2014. The results show that the number of landslides sharply decreased from 273 at the initial stage to less than ten at the second stage of impoundment. Based on this, the reservoir-induced landslides in the TGR region can be roughly classified into five failure patterns, i.e. accumulation landslide, dip-slope landslide, reversed bedding landslide, rockfall, and karst breccia landslide. The accumulation landslides and dip-slope landslides account for more than 90%. Taking the Shuping accumulation landslide (a sliding mass volume of 20.7 × 106 m^3) in Zigui County and the Outang dip-slope landslide (a sliding mass volume of about 90 × 106 m^3) in Fengjie County as two typical cases, the mechanisms of reactivation of the two landslides are analyzed. The monitoring data and factor of safety (FOS) calculation show that the accumulation landslide is dominated by water level variation in the reservoir as most part of the mass body is under 175 m ASL, and the dip-slope landslide is controlled by the coupling effect of reservoir water level variation and precipitation as an extensive recharge area of rainfall from the rear and the front mass is below 175 m ASL. The characteristics of landslide-induced impulsive wave hazards after and before reservoir impoundment are studied, and the probability of occurrence of a landslide-induced impulsive wave hazard has increased in the reservoir region. Simulation results of the Ganjingzi landslide in Wushan County indicate the strong relationship between landslide-induced surge and water variation with high potential risk to shipping and residential areas. Regarding reservoir regulation in TGR when using a single index, i.e. 1-d water level variation, water resources are not well utilized, and there is also potential risk of disasters since 2008. In addition, various indices such as 1-d, 5-d, and 10-d water level variations are proposed for reservoir regulation. Finally, taking reservoir-induced landslides in June 2015 for example, the feasibility of the optimizing indices of water level variations is verified.
基金supported by The National Natural Science Foundation of China(No.81172628)the Fundamental Research Funds for the Central Universities(No.2014305020201)
文摘In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 articles met our inclusion criteria. The overall geometric mean (GM) BLL was 71 μg/L, and the prevalence of elevated BLL (EBLL, defined as BLL ≥100 μg/L) was 18.48% among children. The prevalence of EBLL remained significantly higher among boys. In children less than 6 years of age, there were significantly increasing trends in both BLL and prevalence of EBLL in an age-dependent manner. The ban on leaded gasoline significantly reduced the BLL as well as EBLL prevalence; however, children whose parents had lower educational levels or were exposed to lead in the workplace had a higher EBLL prevalence. Despite its decline over time, the average BLL among children in China remains higher than the average level most recently reported in the United States. Childhood lead poisoning remains a public health problem in China.
文摘To the Editor:We read with great interest the article by Yang et al.[1]evaluating the effects of postoperative serum total cholesterol(s TC)changes on early allograft dysfunction and survival after living donor liver transplantation(LDLT).By the multivariate regression analysis,they showed that patients with s TC<1.42 mmol/L on postoperative day 3 had 4.08-fold and 2.72-fold greater risks of
基金supported by National Key Research and Development Plan of China“Basic Theory and Methods for Resilience Assessment and Risk Control of Transportation Infrastructures”(2021YFB2600500)the National Nature Science Foundation of Si Chuan(2023NSFSC0388)the Joint Research Fund for Earthquake Science launched by the National Natural Science Foundation of China and China Earthquake Administration(U2039208).
文摘Purpose–The smoothness of the high-speed railway(HSR)on the bridge may exceed the allowable standard when an earthquake causes vibrations for HSR bridges,which may threaten the safety of running trains.Indeed,few studies have evaluated the exceeding probability of rail displacement exceeding the allowable standard.The purposes of this article are to provide a method for investigating the exceeding probability of the rail displacement of HSRs under seismic excitation and to calculate the exceeding probability.Design/methodology/approach–In order to investigate the exceeding probability of the rail displacement under different seismic excitations,the workflow of analyzing the smoothness of the rail based on incremental dynamic analysis(IDA)is proposed,and the intensity measure and limit state for the exceeding probability analysis of HSRs are defined.Then a finite element model(FEM)of an assumed HSR track-bridge system is constructed,which comprises a five-span simply-supported girder bridge supporting a finite length CRTS II ballastless track.Under different seismic excitations,the seismic displacement response of the rail is calculated;the character of the rail displacement is analyzed;and the exceeding probability of the rail vertical displacement exceeding the allowable standard(2mm)is investigated.Findings–The results show that:(1)The bridge-abutment joint position may form a step-like under seismic excitation,threatening the running safety of high-speed trains under seismic excitations,and the rail displacements at mid-span positions are bigger than that at other positions on the bridge.(2)The exceeding probability of rail displacement is up to about 44%when PGA 50.01g,which is the level-five risk probability and can be described as’very likely to happen’.(3)The exceeding probability of the rail at the mid-span positions is bigger than that above other positions of the bridge,and the mid-span positions of the track-bridge system above the bridge may be the most hazardous area for the running safety of trains under seismic excitation when high-speed trains run on bridges.Originality/value–The work extends the seismic hazardous analysis of HSRs and would lead to a better understanding of the exceeding probability for the rail of HSRs under seismic excitations and better references for the alert of the HSR operation.
文摘The present work aims to identify flood hazards and risks, particularly to the Attanagalu Oya river basin in Gampaha district, the western province in Sri Lanka. Attanagalu Oya river catchment area periodically faced flood hazards. The flood is categorized by complex like 2008, 2010, 2016, 2017, and it chose 2016 as the primary flood event. Study areas have been selected depending on data availability. Attanagalu Oya river basin is mainly focused as a study area. However, here selected only four Grama Niladhari Divisions are as a sample area. Those are;Kirindivita, Ambanvita, Thammita West, Gonagaha1. Furthermore, many flood hazards can be identified when considering the flood events history. But here selected only two years were 2010 and 2016. These two years were selected with high flood events. For the study, that flood series used 1 feet elevation contours used to identify flood levels and used LiDAR image to identify risk areas in the study site. Due to the blockage of the main waterways that discharge water into the Negombo Lagoon, limited water transportation, low lying land reclamation for development, mainly affect paddy lands and roads, and flood as a major problem identified temporarily and spatially. Eventually, the study could identify flood-prone areas and map the risk zones within the study area.
文摘This work describes the development,optimisation and validation of an analytical method for the rapid determination of 17 priority pharmaceutical compounds and endocrine disrupting chemicals(EDCs).Rather than studying compounds from the same therapeutic class,the analyses aimed to determine target compounds with the highest risk potential(with particular regard to Scotland),providing a tool for further monitoring in different water matrices.Prioritisation was based on a systematic environmental risk assessment approach,using consumption data;wastewater treatment removal efficiency;environmental occurrence;toxicological effects;and pre-existing regulatory indicators.This process highlighted 17 compounds across various therapeutic classes,which were then quantified,at environmentally relevant concentrations,by a single analytical methodology.Analytical determination was achieved using a single-step solid phase extraction(SPE)procedure followed by high-performance liquid chromatography with tandem mass spectrometry(HPLC-MS/MS).The fully optimised method performed well for the majority of target compounds,with recoveries>71%for 15 of 17 analytes.The limits of quantification for most target analytes(14 of 17)ranged from 0.07 ng/L to 1.88 ng/L in river waters.The utility of this method was then demonstrated using real water samples associated with a rural hospital/setting.Eight compounds were targeted and detected,with the highest levels found for the analgesic,paracetamol(at up to 105,910 ng/L in the hospital discharge).This method offers a robust tool to monitor high priority pharmaceutical and EDC levels in various aqueous sample matrices.
基金supported by the Special Research Project for the National Environmental Protection Public Welfare Industry of China(No.201009032)the Strategic Pilot Science and Technology Project of Chinese Academy of Sciences(Class B)(No.XDB05010200)the Project of National Natural Science Foundation of China(No.41175111)
文摘Ambient benzene homologues were measured at a site in the northeastern urban area of Beijing, China, from August 24 to September 4, 2012 by SUMMA canister sampling followed by laboratory determination using cryogenic cold trap pre-concentration-GC-MS/FID, and their health risks were also assessed. Daily total benzene homologues ranged from 0.99 to 49.71 μg/m3 with an average of 11.98 μg/m3. Benzene homologues showed higher concentrations in the morning and evening than that at noontime. Comparison with previous studies revealed a trend of decrease for ambient benzene homologues probably due to the effective emission control in Beijing in recent years. Vehicular exhaust was the main source while volatilization of paints and solvents also made substantial contributions. Health risk assessment showed that BTEX (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) and styrene had no appreciable adverse non-cancer health risks for the exposed population, while benzene has potential cancer risk of 1.34E-05. Available data from cities in China all implied that benzene imposes relatively higher cancer risk on the exposed populations and therefore strict control measures should be taken to further lower ambient benzene levels in China.
文摘Deficiency of the Preventive Erosion Capacity (PEC) of a bridge pier is the main factor leading to bridge fai lures. In this paper, the PEC of bridge piers was analyzed using the stochastic analysis method. The definitions of the reliability and risk level of a bridge p ier subjected to water erosion were proposed and a computational model for erosi on depth and risk level in was suggested.
基金National Key Research and Development Program of China(No.2022YFC3803000).
文摘According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was developed using principles from complex network theory.The vulnerability and risk level of each edge in this model were calculated,and high-risk edges and disaster chains were identified.The analysis reveals that the edge“floods→building collapses”has the highest vulnerability.Implementing measures to mitigate this edge is crucial for delaying the spread of secondary disasters.The highest risk is associated with the edge“building collapses→casualties,”and increased risks are also identified for chains such as“earthquake→building collapses→casualties,”“earthquake→landslides and debris flows→dammed lakes,”and“dammed lakes→floods→building collapses.”Following an earthquake,the prompt implementation of measures is crucial to effectively disrupt these chains and minimize the damage from secondary disasters.
基金supported financially by the National Natural Science Foundation of China(Grant No.51978449)was conducted based on the results of“the 13th Five Year”National Science and Technology Ma-jor Project of China(Grant No.2018YFC0704500)National Natural Science Foundation of China(Grant No.51378336).
文摘Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.In this regard,the research proposes to construct the correlation between climatic design conditions and indoor thermal environment risk level,and explore the effect of uncertainty in building thermal performance on this correlation from the perspective of probability,thus realizing the process of selecting the climatic design conditions based on the requirement for indoor thermal environment risk level.Taking Guangzhou in China as an example,the new process of determining climatic design conditions is realized.On this basis,the difference between the traditional method and the present research method is compared.In the Chinese norm method,the indoor thermal environ-ment risk level of the building is between 0 and 0.03%when the climatic design conditions are selected with 0.57%cumulative frequency of occurrence;in the research method,the indoor thermal environment risk level of the building is between 0.2%and 0.6%when the climatic design conditions are selected with 0.57%indoor thermal environment risk level and 100%confidence level.The results indicate that the research method can meet the designer’s expectation for indoor thermal environment risk level in design more directly and accurately.
文摘This report addresses the role of radiation dose rate effects on stochastic risks for low linear energy transfer (LET) radiation .The chernobyl nuclear power
文摘Abstract Objectives To investigate the relationship between the β-fibrinogen gene -455A/G polymorphism and plasma fibrinogen level and to determine the influence of the mutation on ischemic stroke. Methods Ninety-one patients (63.5±10.1 years) with ischemic stroke and 74 elderly control subjects (60.6±10.8 years) without any thromboembolic events and 98 healthy blood donators as young control (37.5±13.3 years) were enrolled in this trial. The β-fibrinogen gene -455A/G polymorphism was analyzed for all subjects by PCR-RFLP with the restrictive enzyme Hae Ⅲ, while plasma fibrinogen levels were obtained from the prothrombin time (PT) assay. For statistical analysis, the parameters were compared between any two different groups by the unpaired Student’s t test and the Chi-square test. Before analysis, log transformations for concentrations of fibrinogen were carried out.Results H2 allele frequency was higher in male ischemic stroke patients than in the elderly control (22.7% vs 7.1%, χ 2=5.56, P【0.02). There was no significant difference between the female groups. In those patients without any thromboembolic events (both elderly and young control groups), the frequency of H2 decreased with age (≤40, 21.3%; 41-59, 15.4%; and ≥60, 10.2%). In the male elderly and young control groups, the level of plasma fibrinogen was lower in the H1H1 genotype (287±96*!mg/dl and 234±58*!mg/dl) than in H1H2 and H2H2 (331±44*!mg/dl and 307±55*!mg/dl; t=2.53 and 9.67, P【0.05). In the female elderly groups, this tendency was not found.Conclusion Plasma fibrinogen expression is affected by the β-fibrinogen gene -455A/G polymorphism, and the H2 allele may be a risk factor for ischemic stroke in Chinese males.
基金supported by the National Basic Research Program (973) of China (Nos. 2013CB430004, 2014CB460612)the National Natural Science Foundation of China (Nos. 41422306, 21120102040)the Young Scientists Fund of Research Center for Eco-Environmental Sciences (No. RCEES-QN-20130007F)
文摘As a global pollutant, high levels of mercury(Hg) have been found in remote ecosystem due to the long range atmospheric transport. In this study, a total of 60 fish samples were collected from four rivers across the Tibetan Plateau to study the accumulation of Hg in remote and high-altitude aquatic environment. The total Hg(THg) and methylmercury(MeHg) in fish muscles ranged from 11 to 2097 ng/g dry weight(dw)(average: 819 ng/g dw)and from 14 to 1960 ng/g dw(average: 756 ng/g dw), respectively. Significantly positive linear relationships were observed between the THg(r = 0.591, p 〈 0.01, n = 36) and MeHg concentrations(r = 0.473, p 〈 0.01, n = 36) with the trophic level of fish from Lhasa River,suggesting trophic transfer and biomagnification of Hg in this aquatic ecosystem. Moreover,the THg levels in fish had significantly positive correlations with the length(r = 0.316,p 〈 0.05, n = 60) and weight(r = 0.271, p 〈 0.05, n = 60) of fish. The high levels of Hg were attributed to the slow growth and long lifespan of the fish under this sterile and cold environment. Risk assessment revealed that the consumption of Oxygymnocypris stewartii,Schizothorax macropogon, Schizothorax waltoni, Schizopygopsis younghusbandi and Schizothorax o'connori would lead to a high exposure to Me Hg.