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Trends of environmental accidents and impact factors in China

Pengli XUE, Weihua ZENG

《环境科学与工程前沿（英文）》 2011年第5卷第2期页码 266-276 doi: 10.1007/s11783-010-0267-1

摘要： An overview of the spatial and temporal variations of the environmental accidents in China in recent years was presented in this paper using available data. The results showed that the frequency of pollution accidents was significantly decreased, from 3462 in 1990 to 462 in 2007. The water and air pollution accidents were found to be the dominant types, accounting for more than 80% of the total accidents. Considering the classification of environmental accidents at 4 scales, the general environmental accident, i.e., the least serious type, was the most frequent event, taking up 58.98% of the total pollution accidents. In addition, the distribution of environmental accidents was generally in accordance with the industrial layout in the country during the past decade. It is very important to note that the extraordinarily severe environmental accidents showed an increasing trend in underdeveloped regions, which was caused by the transfer and the development of heavy polluted industry in these areas. As to the losses of environmental accidents, the casualties presented an obvious reduction tendency, while the direct economic loss per accident tended to climb up. Furthermore, some key factors that affect the spatial and temporal tendencies of environmental accidents in China were discussed and some suggestions were put forward, hoping to shed light on environmental risk management and emergency plans making associated with environmental accidents in China.

关键词： environmental accidents spatial and temporal trends environmental risk

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Interaction and independence on methane oxidation of landfill cover soil among three impact factors:

Pinjing HE, Na YANG, Wenjuan FANG, Fan Lü, Liming SHAO

《环境科学与工程前沿（英文）》 2011年第5卷第2期页码 175-185 doi: 10.1007/s11783-011-0320-8

摘要： To understand the influence patterns and interactions of three important environmental factors, i.e. soil water content, oxygen concentration, and ammonium addition, on methane oxidation, the soils from landfill cover layers were incubated under full factorial parameter settings. In addition to the methane oxidation rate, the quantities and community structures of methanotrophs were analyzed to determine the methane oxidation capacity of the soils. Canonical correspondence analysis was utilized to distinguish the important impact factors. Water content was found to be the most important factor influencing the methane oxidation rate and Type II methanotrophs, and the optimum value was 15% (w/w), which induced methane oxidation rates 10- and 6- times greater than those observed at 5% (w/w) and 20% (w/w), respectively. Ambient oxygen conditions were more suitable for methane oxidation than 3% oxygen. The addition of of ammonium induced different effects on methane oxidation capacity when conducted at low or high water content. With regard to the methanotrophs, Type II was sensitive to the changes of water content, while Type I was influenced by oxygen content. Furthermore, the methanotrophic acidophile, , was detected in soils with a pH of 4.9, which extended their known living environments.

关键词： quantitative polymerase chain reaction (PCR) denaturing gradient gel electrophoresis (DGGE) principal component analysis (PCA) canonical correspondence analysis (CCA)

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Study on factors affecting TB/HIV co-infection in four counties of China

Shi-Ming CHENG MD, Yu-Ji LAI MS, Er-Yong LIU MS, Lin ZHOU MD, Xue-Jing WANG MS, Qiu-Lan CHEN MS, Dong-Ming LI MS, Ning WANG MD,

《医学前沿（英文）》 2010年第4卷第2期页码 185-191 doi: 10.1007/s11684-010-0040-7

摘要： The factors affecting case detection of tuberculosis (TB)/human immunodeficiency virus (HIV) co-infection cases were explored in order to provide evidence-based formulation of a TB/HIV co-infection control strategy in China. Four counties with different modes of HIV transmission and varying cooperation mechanisms between TB and HIV institutions were selected. HIV test among TB patients and TB examination among people living with HIV/acquired immunodeficiency syndrome (AIDS) were conducted. Patients also completed questionnaires on potential factors affecting TB/HIV co-infection. The results showed that 19 (1.7%) were HIV-positive among 1089 cases of people living with active TB who received HIV testing. Conversely, there were 126 (10%) cases of active TB among 1255 cases of people living with HIV/AIDS. Among the newly discovered 145 cases of TB/HIV co-infection, AIDS institutions found 86.9% of these co-infections and 14.1% came from TB institutes. In different registration categories, there were 31 (21.4%) cases of smear positive TB, 104 (71.7%) cases of smear negative TB, and extrapulmonary cases accounted for 10 (6.9%). Gender, occupation, marital status, ethnic group, education, HIV transmission route, CD4 level, and type of TB susceptible symptoms had significant effects on whether HIV/AIDS patients were co-infected with TB disease (<0.01). Sex, age, ethnic group, occupation, and type of tuberculosis had no significant influence on whether TB patients had HIV infection. AIDS institutions could find more TB/HIV co-infection patients in comparison with TB institutions, particularly in patients with smear negative pulmonary tuberculosis and extrapulmonary tuberculosis. Therefore, a cooperation mechanism should be built up between TB and HIV control systems, and routine TB checks should be conducted for HIV/AIDS patients. In areas where sex or drug use is the major transmission mode of HIV infection, antiretroviral therapy should be expanded, treatment adherence should be improved and patients’ immunity level should be increased in order to decrease TB incidence. Cough and expectoration of more than two weeks, bloody sputum, and recurrent fevers could be revealing symptoms in TB screening of HIV/AIDS patients.

关键词： tuberculosis/acquired immunodeficiency syndrome dual infection prevention and control case detection impact factors

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数控机床精度评价新方法

赵万华,张俊,刘辉,杨晓君

《中国工程科学》 2013年第15卷第1期页码 93-98

摘要：

传统的定位精度与重复定位精度等指标是在准静态下评价数控机床（CNC）性能的，无法反映数控机床在运动和加工过程中的精度。首先从数控机床的数控、伺服、机械等环节在服役态下所表现出来的性能出发，提出一种对数控机床更有针对性的，以运动精度为指标的机床精度评价新方法，通过数控指令与运动轴实际位移的符合程度即运动精度来评价机床精度，然后给出了具体的评价指标，并提出了评价指标的测量方法。分析表明，这种新的机床运动精度描述评价方法能够系统、全面地评价数控机床关键性能的优劣。最后从数控、伺服和机械角度分别阐述了影响运动精度的因素。

关键词：数控机床运动精度评价指标影响因素

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Meta-analysis of the risk factors of breast cancer concerning reproductive factors and oral contraceptive

Qiong DAI MD, Bei LIU MD, Yukai DU MM,

《医学前沿（英文）》 2009年第3卷第4期页码 452-458 doi: 10.1007/s11684-009-0080-z

摘要： The authors performed a meta-analysis of case-control studies that addressed whether reproductive factors and oral contraceptive use were associated with breast cancer by searching the MEDLINE, PubMed, Proquest, Embase, ScienceDirect, African Healthline, BMJ Health Intelligence and Chinese Periodical net databases for all English-language and Chinese-language papers published from January 1, 1997 to December 31, 2007. A total of 15 studies calculating pool ORs indicated that menopausal age >50yr [odds ratio (OR), 1.39; 95% confidence interval (CI), 1.22―1.57] and oral contraceptive use (OR, 2.12*, “*”: summary OR was adjusted; 95% CI, 1.24―3.62) were correlated with the increase in breast cancer risk while the summary OR based on number of full-term pregnancies ≥1 (OR, 0.63*; 95% CI, 0.60―0.68) and breast-feeding (OR, 0.76; 95% CI, 0.64―0.90) indicated no association with breast cancer risk. The correlation was statistically significant. Menopausal age >50yr and oral contraceptive use are positively correlated with an increase in breast cancer risk while breast-feeding and number of full-term pregnancies ≥1 are protective factors.

关键词： meta-analysis breast cancer risk factors reproductive factors oral contraceptive use

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Risk factors of prognosis after acute kidney injury in hospitalized patients

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《医学前沿（英文）》 2017年第11卷第3期页码 393-402 doi: 10.1007/s11684-017-0532-9

摘要：

The risk factors, especially laboratory indicators, of prognosis after acute kidney injury (AKI) remain unclear. We conducted a retrospective survey of Chinese People’s Liberation Army General Hospital from January 1, 2012 to December 31, 2012 according to the AKI diagnosis standard issued by Kidney Disease Improving Global Outcomes. The epidemiological features and factors influencing hospital mortality and renal function recovery were evaluated through logistic regression analysis. Among 77 662 cases of hospitalized patients, 1387 suffered from AKI. The incidence rate and mortality of AKI were 1.79% and 14.56%, respectively. Multivariate logistic regression analysis revealed that high AKI stage, age greater than 80 years, neoplastic disease, low cardiac output, increased white blood cell count, and decreased platelet count and serum albumin levels were the risk factors affecting the mortality of AKI patients. Conversely, body mass index between 28 and 34.9 was a protective factor. Increased AKI stage, tumor disease, post-cardiopulmonary resuscitation, and RRT were the risk factors of renal function recovery upon discharge. In addition to traditional risk factors, white blood cell count, platelet count, albumin, and BMI were the predictors of the mortality of AKI patients. No laboratory indicators were found to be the risk factors of renal function recovery in AKI patients.

关键词： acute kidney injury risk factors prognosis

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Game theoretic analysis of environmental impact assessment system in China

CHENG Hongguang, PU Xiao, GONG Li, QI Ye

《环境科学与工程前沿（英文）》 2007年第1卷第4期页码 448-453 doi: 10.1007/s11783-007-0071-8

摘要： Environmental impact assessment (EIA) system has been established in China since 1973. In present EIA cases, there are four participants in general: governments, enterprises, EIA organizations and the public. The public has held re

关键词： public impact assessment Environmental impact general

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The clinical impact of tricuspid regurgitation in patients with a biatrial orthotopic heart transplant

《医学前沿（英文）》 2023年第17卷第3期页码 527-533 doi: 10.1007/s11684-022-0967-5

摘要： In this study, we aim to elucidate the clinical impact and long-term course of tricuspid regurgitation (TR), taking into account its dynamic nature, after biatrial orthotopic heart transplant (OHT). All consecutive adult patients undergoing biatrial OHT (1984−2017) with an available follow-up echocardiogram were included. Mixed-models were used to model the evolution of TR. The mixed-model was inserted into a Cox model in order to address the association of the dynamic TR with mortality. In total, 572 patients were included (median age: 50 years, males: 74.9%). Approximately 32% of patients had moderate-to-severe TR immediately after surgery. However, this declined to 11% on 5 years and 9% on 10 years after surgery, adjusted for survival bias. Pre-implant mechanical support was associated with less TR during follow-up, whereas concurrent LV dysfunction was significantly associated with more TR during follow-up. Survival at 1, 5, 10, 20 years was 97% ± 1%, 88% ± 1%, 66% ± 2% and 23% ± 2%, respectively. The presence of moderate-to-severe TR during follow-up was associated with higher mortality (HR: 1.07, 95% CI (1.02–1.12), p = 0.006). The course of TR was positively correlated with the course of creatinine (R = 0.45). TR during follow-up is significantly associated with higher mortality and worse renal function. Nevertheless, probability of TR is the highest immediately after OHT and decreases thereafter. Therefore, it may be reasonable to refrain from surgical intervention for TR during earlier phase after OHT.

关键词： orthotopic heart transplant tricuspid regurgitation clinical impact biatrial heart transplantation

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Dynamical analysis of droplet impact spreading on solid substrate

Zhaomiao LIU, Huamin LIU, Xin LIU,

《机械工程前沿（英文）》 2010年第5卷第3期页码 308-315 doi: 10.1007/s11465-010-0020-2

摘要： This paper investigates the impact spreading of a droplet on a solid substrate using numerical simulation on the basis of a volume-of-fluid (VOF) model. The process of droplet spreading is described, the analysis of low speed and high speed droplet spreading, and more than one droplet spreading simultaneously is performed. The pressure, velocity, and spreading factor during the droplet spreading are reported. According to the spreading factor’s evolvement, the process of droplet spreading can be classified into spreading phase and recoiling phase. The spreading factors are almost the same at the low speed droplet spreading; however, the pressures on the substrate are quite different and air entrainment may be found as the impact speeds in a certain range. The impact speed impacts on the spreading factors in high speed droplet spreading. The spreading factor obviously increases with increasing impact speed; however, splashing will appear in the status when the speed is high enough in the high speed droplet spreading. The distance between the neighbor droplets affects the film’s quality, and only the distance between the static diameter and the maximum diameter can ensure the film’s quality. The results could help in understanding the process of droplet spreading and provide advice on the operation of a spray coating process.

关键词： droplet impact spreading numerical simulation

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Factors affecting the distribution of microplastics in soils of China

《环境科学与工程前沿（英文）》 2023年第17卷第9期 doi: 10.1007/s11783-023-1710-4

摘要：

● Microplastic (MP) abundance in soil of China was highly heterogeneous.

关键词： Microplastic distribution Microplastic heterogeneity Effecting factors Agriculture Socio-economic factors

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Epidemic obesity in children and adolescents: risk factors and prevention

Eun Young Lee, Kun-Ho Yoon

《医学前沿（英文）》 2018年第12卷第6期页码 658-666 doi: 10.1007/s11684-018-0640-1

摘要： The prevalence of obesity among children and adolescents (aged 2–18 years) has increased rapidly, with more than 100 million affected in 2015. Moreover, the epidemic of obesity in this population has been an important public health problem in developed and developing countries for the following reasons. Childhood and adolescent obesity tracks adulthood obesity and has been implicated in many chronic diseases, including type 2 diabetes, hypertension, and cardiovascular disease. Furthermore, childhood and adolescent obesity is linked to adulthood mortality and premature death. Although an imbalance between caloric intake and physical activity is a principal cause of childhood and adolescent obesity, environmental factors are exclusively important for development of obesity among children and adolescents. In addition to genetic and biological factors, socioenvironmental factors, including family, school, community, and national policies, can play a crucial role. The complexity of risk factors for developing obesity among children and adolescents leads to difficulty in treatment for this population. Many interventional trials for childhood and adolescent obesity have been proven ineffective. Therefore, early identification and prevention is the key to control the global epidemic of obesity. Given that the proportion of overweight children and adolescents is far greater than that of obesity, an effective prevention strategy is to focus on overweight youth, who are at high risk for developing obesity. Multifaceted, comprehensive strategies involving behavioral, psychological, and environmental risk factors must also be developed to prevent obesity among children and adolescents.

关键词： obesity children adolescents epidemiology risk factor prevention

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CRITICAL PROCESSES AND MAJOR FACTORS THAT DRIVE NITROGEN TRANSPORT FROM FARMLAND TO SURFACE WATER BODIES

《农业科学与工程前沿（英文）》 2023年第10卷第4期页码 541-552 doi: 10.15302/J-FASE-2023518

摘要：

Agricultural non-point source pollution is increasingly an important issue affecting surface water quality. Currently, the majority of the studies on nitrogen loss have focused on the agricultural field scale, however, the response of surface water quality at the watershed scale into the nitrogen loss at the field scale is poorly understood. The present study systematically reviewed the critical processes and major factors that nitrogen transport from farm fields to surface water bodies. The critical processes of farmland nitrogen entering surface water bodies involve the processes of nitrogen transport from farmland to ditches and the transformation processes of nitrogen during migration in ditches/rivers. Nitrogen transport from farmland to ditches is one of the prerequisites and critical processes for farmland nitrogen transport to surface water bodies. The transformation of nitrogen forms in ditches/rivers is an intermediate process in the migration of nitrogen from farmland to surface water bodies. Nitrogen loss from farmland is related to soil storage and exogenous inputs. Therefore, nitrogen input management should not only consider the current input, but also the contribution of soil storage due to the historical surpluses. Ditches/rivers have a strong retention capacity for nitrogen, which will significantly affect the process of farmland nitrogen entering surface water bodies. The factors affecting nitrogen transformation in river/ditches can be placed in four categories: (1) factors affecting hydraulic retention time, (2) factors affecting contact area, (3) factors affecting biological activity, and (4) forms and amount of nitrogen loading to river/ditches. Ditch systems are more biologically (including plants and microbes) active than rivers with biological factors having a greater influence on nitrogen transformation. When developing pollution prevention and control strategies, ecological ditches can be constructed to increase biological activity and reduce the amount of surplus nitrogen entering the water body. The present research should be valuable for the evaluation of environment impacts of nitrogen loss and the non-point source pollution control.

关键词： nitrogen loss from soil transformation farm field scale watershed scale

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Oocyte-associated transcription factors in reprogramming after somatic cell nuclear transfer: a review

Fengxia YIN,Hui LIU,Shorgan BOU,Guangpeng LI

《农业科学与工程前沿（英文）》 2014年第1卷第2期页码 104-113 doi: 10.15302/J-FASE-2014003

摘要： Oocytes are unique cells with the inherent capability to reprogram nuclei. The reprogramming of the somatic nucleus from its original cellular state to a totipotent state is essential for term development after somatic cell nuclear transfer. The nuclear-associated factors contained within oocytes are critical for normal fertilization by sperm or for somatic cell nuclear reprogramming. The chromatin of somatic nuclei can be reprogrammed by factors in the egg cytoplasm whose natural function is to reprogram sperm chromatin. The oocyte first obtains its reprogramming capability in the early fetal follicle, and then its capacity is enriched in the late growth phase and reaches its highest capability for reprogramming as fully-grown germinal vesicle oocytes. The cytoplasmic milieu most likely contains all of the specific transcription and/or reprogramming factors necessary for cellular reprogramming. Certain transcription factors in the cytoplast may be critical as has been demonstrated for induced pluripotent stem cells. The maternal pronucleus exerts a predominant, transcription-dependent effect on embryo cytofragmentation, with a lesser effect imposed by the ooplasm and the paternal pronucleus. With deep analysis of transcriptomics in oocytes and early developmental stage embryos more maternal transcription factors inducing cellular reprogramming will be identified.

关键词： nuclear reprogramming somatic cell transcription factors transcriptomics

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Understanding coupled factors that affect the modelling accuracy of typical planar compliant mechanisms

Guangbo HAO,Haiyang LI,Suzen KEMALCAN,Guimin CHEN,Jingjun YU

《机械工程前沿（英文）》 2016年第11卷第2期页码 129-134 doi: 10.1007/s11465-016-0392-z

摘要：

In order to accurately model compliant mechanism utilizing plate flexures, qualitative planar stress (Young’s modulus) and planar strain (plate modulus) assumptions are not feasible. This paper investigates a quantitative equivalent modulus using nonlinear finite element analysis (FEA) to reflect coupled factors in affecting the modelling accuracy of two typical distributed-compliance mechanisms. It has been shown that all parameters have influences on the equivalent modulus with different degrees; that the presence of large load-stiffening effect makes the equivalent modulus significantly deviate from the planar assumptions in two ideal scenarios; and that a plate modulus assumption is more reasonable for a very large out-of-plane thickness if the beam length is large.

关键词： coupling factors modelling accuracy compliant mechanisms equivalent modulus

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Changes in major factors affecting the ecosystem health of the Weihe River in Shaanxi Province, China

Qi LI, Jinxi SONG, Anlei WEI, Bo ZHANG

《环境科学与工程前沿（英文）》 2013年第7卷第6期页码 875-885 doi: 10.1007/s11783-013-0568-2

摘要： Maintenance of the ecosystem health of a river is of great importance for local sustainable development. On the basis of both qualitative and quantitative analysis of the influence of natural variations and human activities on the ecosystem function of the Weihe River, the changes in major factors affecting its ecosystem health are determined, which include: 1) Deficiency of environment flow: since the 1960s, the incoming stream flow shows an obvious decreasing tendency. Even in the low flow period, 80% of the water in the stream is impounded by dams for agriculture irrigation in the Baoji district. As a result, the water flow maintained in the stream for environmental use is very limited. 2) Deterioration of water quality: the concentrations of typical pollutants like Chemical Oxygen Demand (COD) and NH -N are higher than their maximum values of the Chinese environmental quality standard. Very few fish species can survive in the River. 3) Deformation of water channels: the continuous channel sedimentation has resulted in the decrease in stream gradient, shrinkage of riverbed and the decline in the capability for flood discharge. 4) Loss of riparian vegetation: most riparian land has been occupied by urban construction activities, which have caused the loss of riparian vegetation and biodiversity and further weakened flood control and water purification functions.

关键词： influencing factors ecosystem health ecological and environmental functions the Weihe River Shaanxi Province