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
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
This paper focuses on the dynamic variation of groundwater level in Lhasacity. According to the data, the obvious characteristic of the groundwater level of the city is thatit is changing seasonally. Lhasa is divided ...This paper focuses on the dynamic variation of groundwater level in Lhasacity. According to the data, the obvious characteristic of the groundwater level of the city is thatit is changing seasonally. Lhasa is divided into three districts according to hydrogeologicalconditions: the alluvial plain of the Lhasa-river, the alluvial plain of the Doilung-river, and thealluvial fan of inter mountain, which presents a downward trend, a slight upward trend and basicallystabilizing trend over the years individually. The analysis indicates that meteorological andhydrological factors lead to the obvious dynamic change of the groundwater level. However, more andmore human activities and over-exploitation of the groundwater cause the downward trend inthegroundwater level.展开更多
The nuclear spin relaxation rate （l/T1） is measured for GaAs two-dimensional （2D） electron systems in the quantum Hall regime with an all-electrical technique for agitating and probing the nuclear spins. A ＂tilte...The nuclear spin relaxation rate （l/T1） is measured for GaAs two-dimensional （2D） electron systems in the quantum Hall regime with an all-electrical technique for agitating and probing the nuclear spins. A ＂tilted plateau＂ feature is observed near the Landau level filling factor v = 1 in 1/T1 versus v. Both the width and magnitude of the plateau increase with decreasing electron density. At low temperatures, lIT1 exhibits an Arrhenius temperature dependence within the tilted plateau regime. The extracted energy gaps are up to two orders of magnitude smaller than the corresponding charge transport gaps. These results point to a nontrivial mechanism for the disorder-enhanced nuclear spin relaxation, in which microscopic inhomogeneities play a key role for the low energy spin excitations related to skyrmions.展开更多
The dynamic characteristics and influencing factors of groundwater level in Qianyang County were analyzed.The results showed that in the south bank of the Qianhe River,the change of groundwater level was mainly affect...The dynamic characteristics and influencing factors of groundwater level in Qianyang County were analyzed.The results showed that in the south bank of the Qianhe River,the change of groundwater level was mainly affected by precipitation,and the response of the groundwater level to the change of precipitation was one year later.The groundwater level presented a downward trend on the whole.In the north bank of the Qianhe River,the supply source of the groundwater level included precipitation and hydrology,and the groundwater level showed a rising trend on the whole.In the plain area,there was a sudden change in the groundwater level under the control of human activities.In a word,the main factors influencing the groundwater level in various geological conditions were different,so there were great differences between various regions in the dynamic characteristics of the groundwater level in Qianyang County.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
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
To promote modern agricultural equipment level is one characteristic of constructing and developing modern agriculture in China.This paper makes up stepwise linear regression analysis model of influence factors of mod...To promote modern agricultural equipment level is one characteristic of constructing and developing modern agriculture in China.This paper makes up stepwise linear regression analysis model of influence factors of modern agricultural equipment level,and chooses rural labor,per capita income of rural residents,rural investment,proportion of people at secondary education level and at higher level in per hundred rural labor force and arable land area as independent variables,and total power of machine as induced variable.The major results show that the relativity of modern agricultural equipment level,rural investment and education level of peasants is remarkable,and they are the major influence factors of modern agricultural equipment level.Raising investment level of rural infrastructure construction as well as and research and development and promotion of advanced and applicable modern agricultural equipment,improving quality and education level of peasants can accelerate the development of China's modern agricultural equipment effectively in the process of agricultural sustainable development.展开更多
This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct(PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power...This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct(PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power components,overall system loss and magnetic component selection based upon the single-level boost PFC switch converter.Besides,relying on the application of mi-croprocessor in power converter technology and DSP(Digital Signal Processing) chip's strong cal-culating capacity,the letter presents the adoption of modified scheme of tri-level boost PFC converter under the control of predictive control algorithm.Moreover,the operating principle and control method are specified,the results of circuit test and analysis are provided and the advantages of pre-dictive control technology-based multi-level boost PFC converter is verified.展开更多
Background: The aim of the current study was to evaluate the anthropometric and demographic factors and their correlation with type 2 diabetes mellitus (T2DM) in Bangladesh. Methods: One hundred fourteen patients (70 ...Background: The aim of the current study was to evaluate the anthropometric and demographic factors and their correlation with type 2 diabetes mellitus (T2DM) in Bangladesh. Methods: One hundred fourteen patients (70 males and 44 females) between 30 and 75 years of age from various areas of Bangladesh were screened for T2DM. Fasting blood sugar (FBS) was analyzed by using laboratory kits and spectrophotometric technique. Anthropometric and socio-demographic data were collected using a structured questionnaire. Body mass index (BMI) was calculated from weight (kg) and height (m) of the individual respondents. Physical activity was categorized based on activity during daily work. Economic condition is defined by respective family income and education level is categorized into 3 levels: illiterate, 0 - 12 years of education and graduate or above. Results: According to the current study results, half of the patients were from the middle-class family with low physical activity and their age was within the range of 30 - 45 years. The male and female ratio of the study population was 60:40. Most of the patients were found to be obese and educated. Urban populations were more prone to have DM than the rural population. Age, education, the area of residence (urban and rural), physical activity and co-morbid diseases were significantly correlated with T2DM in Bangladesh (P Conclusion: Our study shows that different socio-demographic factors have a significant correlation with T2DM in Bangladesh. Diabetes awareness, early diagnosis, patient education and life-style modification can be initiated to manage T2DM efficiently.展开更多
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.
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This paper focuses on the dynamic variation of groundwater level in Lhasacity. According to the data, the obvious characteristic of the groundwater level of the city is thatit is changing seasonally. Lhasa is divided into three districts according to hydrogeologicalconditions: the alluvial plain of the Lhasa-river, the alluvial plain of the Doilung-river, and thealluvial fan of inter mountain, which presents a downward trend, a slight upward trend and basicallystabilizing trend over the years individually. The analysis indicates that meteorological andhydrological factors lead to the obvious dynamic change of the groundwater level. However, more andmore human activities and over-exploitation of the groundwater cause the downward trend inthegroundwater level.
基金Project supported by the National Basic Research Program of China(Grant Nos.2012CB921703 and 2015CB921102)the National Natural Science Foundation of China(Grant Nos.91121003,11374337,and 61425015)the Chinese Academy of Sciences,the BMBF,and the German–Israel Foundation
文摘The nuclear spin relaxation rate （l/T1） is measured for GaAs two-dimensional （2D） electron systems in the quantum Hall regime with an all-electrical technique for agitating and probing the nuclear spins. A ＂tilted plateau＂ feature is observed near the Landau level filling factor v = 1 in 1/T1 versus v. Both the width and magnitude of the plateau increase with decreasing electron density. At low temperatures, lIT1 exhibits an Arrhenius temperature dependence within the tilted plateau regime. The extracted energy gaps are up to two orders of magnitude smaller than the corresponding charge transport gaps. These results point to a nontrivial mechanism for the disorder-enhanced nuclear spin relaxation, in which microscopic inhomogeneities play a key role for the low energy spin excitations related to skyrmions.
基金Supported by the Key Laboratory Project of Shaanxi Province,China(09JS071)
文摘The dynamic characteristics and influencing factors of groundwater level in Qianyang County were analyzed.The results showed that in the south bank of the Qianhe River,the change of groundwater level was mainly affected by precipitation,and the response of the groundwater level to the change of precipitation was one year later.The groundwater level presented a downward trend on the whole.In the north bank of the Qianhe River,the supply source of the groundwater level included precipitation and hydrology,and the groundwater level showed a rising trend on the whole.In the plain area,there was a sudden change in the groundwater level under the control of human activities.In a word,the main factors influencing the groundwater level in various geological conditions were different,so there were great differences between various regions in the dynamic characteristics of the groundwater level in Qianyang County.
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
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one of the research outputs of the Second China Agricultural Census Projects (Program NO. N1203)Art Development Fund of Ocean University of China (Project No.H07YB02)
文摘To promote modern agricultural equipment level is one characteristic of constructing and developing modern agriculture in China.This paper makes up stepwise linear regression analysis model of influence factors of modern agricultural equipment level,and chooses rural labor,per capita income of rural residents,rural investment,proportion of people at secondary education level and at higher level in per hundred rural labor force and arable land area as independent variables,and total power of machine as induced variable.The major results show that the relativity of modern agricultural equipment level,rural investment and education level of peasants is remarkable,and they are the major influence factors of modern agricultural equipment level.Raising investment level of rural infrastructure construction as well as and research and development and promotion of advanced and applicable modern agricultural equipment,improving quality and education level of peasants can accelerate the development of China's modern agricultural equipment effectively in the process of agricultural sustainable development.
文摘This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct(PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power components,overall system loss and magnetic component selection based upon the single-level boost PFC switch converter.Besides,relying on the application of mi-croprocessor in power converter technology and DSP(Digital Signal Processing) chip's strong cal-culating capacity,the letter presents the adoption of modified scheme of tri-level boost PFC converter under the control of predictive control algorithm.Moreover,the operating principle and control method are specified,the results of circuit test and analysis are provided and the advantages of pre-dictive control technology-based multi-level boost PFC converter is verified.
文摘Background: The aim of the current study was to evaluate the anthropometric and demographic factors and their correlation with type 2 diabetes mellitus (T2DM) in Bangladesh. Methods: One hundred fourteen patients (70 males and 44 females) between 30 and 75 years of age from various areas of Bangladesh were screened for T2DM. Fasting blood sugar (FBS) was analyzed by using laboratory kits and spectrophotometric technique. Anthropometric and socio-demographic data were collected using a structured questionnaire. Body mass index (BMI) was calculated from weight (kg) and height (m) of the individual respondents. Physical activity was categorized based on activity during daily work. Economic condition is defined by respective family income and education level is categorized into 3 levels: illiterate, 0 - 12 years of education and graduate or above. Results: According to the current study results, half of the patients were from the middle-class family with low physical activity and their age was within the range of 30 - 45 years. The male and female ratio of the study population was 60:40. Most of the patients were found to be obese and educated. Urban populations were more prone to have DM than the rural population. Age, education, the area of residence (urban and rural), physical activity and co-morbid diseases were significantly correlated with T2DM in Bangladesh (P Conclusion: Our study shows that different socio-demographic factors have a significant correlation with T2DM in Bangladesh. Diabetes awareness, early diagnosis, patient education and life-style modification can be initiated to manage T2DM efficiently.
