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The stability safety factor calibration based on the reliability index 被引量:1
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作者 Tong Xiaolong Fang Zhi 《Engineering Sciences》 EI 2014年第3期65-69,共5页
When the bridge structure stability safety factor of the first type is 4, the research that whether the structure reliability index will reach target reliability index under the more-likely-to-happen collapse situatio... When the bridge structure stability safety factor of the first type is 4, the research that whether the structure reliability index will reach target reliability index under the more-likely-to-happen collapse situation of the second type is necessary. The stability calculations of the first and the second type are made respectively for single layer and single span rigid frame bridge. Based on the critical load obtained from the stability calculation of the first type, the stability safety factor of the first type is taken as 4, and the first order reliability method is used to program and calculate the reliability index. Then, the load effect under the stability reliability index cal- culation of the first type and the critical load of the second type are employed to calculate the reliability index of the second type. The evaluation of structure stability safety factor is discussed according to reliability index. Based on the discussion above, parameter analysis of the stable critical loads of two types is made, and the in- fluence of critical load change on reliability index is researched. The result shows that stability analysis should identify collapse state; when the stability safety factor of the first type is 4, but the structure has the collapse of the second type, the reliability index cannot be ensured to reach the target reliability index under certain condi- tions. 展开更多
关键词 stability safety factor reliability index RIGID FRAME BRIDGE
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An Assessment of Heavy-Metal Contamination in Soils within Auto-Mechanic Workshops Using Enrichment and Contamination Factors with Geoaccumulation Indexes 被引量:4
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作者 Isaac A. Ololade 《Journal of Environmental Protection》 2014年第11期970-982,共13页
Soil characterization and heavy metals in different layers (0 - 15 cm;15 - 30 cm and 30 - 45 cm depth) of automobile mechanic waste dumps were studied. The soils showed remarkably high levels of all the metals above b... Soil characterization and heavy metals in different layers (0 - 15 cm;15 - 30 cm and 30 - 45 cm depth) of automobile mechanic waste dumps were studied. The soils showed remarkably high levels of all the metals above background concentrations with most (Ni, Cu, Fe, Cr and Cd) decreasing with soil depth. The distribution pattern were in the following order Fe > Cu > Zn > Pb > Cr > Ni > Cd. Across all the sampling locations and profiles, Fe and Cd showed the highest (476.4 μg·g-1) and least (37.5 μg·g-1) mean concentrations respectively. Pollution load index (PLI) and index of geoaccumulation (Igeo) revealed overall high and moderate contamination respectively but the enrichment factors (EFs) for Pb Ni and Cd are severe. The inter-element relationship revealed the identical source of elements in the soils of the studied area. The accuracy of the results has been cheeked using the standard reference material;SRM (PACS-2). The mechanic waste dumps represent potential sources of heavy metal pollution to environment. The elevated levels of heavy metals in these soil profiles constitute a serious threat to both surface and groundwater. 展开更多
关键词 HEAVY Metals SOIL CONTAMINATION SOIL Profiles Automobile MECHANIC ENRICHMENT factor Geoaccumulation index
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Risk factors and ankle brachial indexes in cerebral infarction combined with peripheral arterial disease
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作者 Huihua Liu Jun Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第7期653-656,共4页
BACKGROUND: Ankle brachial index (ABI) is widely involved in researches and clinical application of peripheral vascular injury of patients with diabetes mellitus (DM); however, the application in cerebral infarction (... BACKGROUND: Ankle brachial index (ABI) is widely involved in researches and clinical application of peripheral vascular injury of patients with diabetes mellitus (DM); however, the application in cerebral infarction (CI) is rare. OBJECTIVE: To investigate the possible risk factor of cerebral infarction plus peripheral arterial disease (PAD), compare metabolic characteristics of patients who having CI plus PAD or only having CI, and understand the significance of ABI on screening and diagnosing CI plus PAD of lower limb. DESIGN: Contrast observation based on CI patients. SETTING: Department of Neurology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region. PARTICIPANTS: A total of 124 CI patients were selected from Department of Neurology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region from July 2005 to April 2006, including 72 males and 52 females aged from 45 to 88 years. All patients met the diagnostic criteria of cerebrovascular disease established by National Academic Conference of Cerebrovascular Diseases in 1995 and determined as cerebral infarction with MRI or CT examination. All patients provided informed consent. There were 46 cases (37.2%) with CI plus PAD and 78 cases (62.8%) only with CI. METHODS: Blood pressure of bilateral ankles and upper extremities was measured at plain clinostatism with DINAMAP blood pressure monitor (GE Company). The ratio between average systolic pressure of lateral ankle and average systolic pressure of both upper extremities was regarded as ABI. The normal ABI was equal to or more than 0.9. If ABI < 0.9 occurred at one side, patients were diagnosed as PAD. On the second morning after hospitalization, blood was collected to measure fasting blood glucose (FBG), 2-hour postprandial blood glucose (PBG2h), glycosylated hemoglobin (HbA1c), triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Among them, blood glucose, lipid and other biochemical markers were measured with enzyme chemistry assay and HbA1c was measured with HbA1c meter based on high liquid phase. Measurement data and enumeration data were compared with t test and Chi-square test, and multiple factors were dealt with Logistic regression analysis and multivariate linear regression analysis. MAIN OUTCOME MEASURES: Results of correlation between ABI and metabolic markers with multivariate linear regression analysis; risk factors of CI plus PAD with Logistic regression analysis; comparisons of metabolic markers between PAD and non-PAD patients. RESULTS: All 124 patients with acute CI were involved in the final analysis. ① Comparisons of metabolic markers: Levels of serum LDL-C and uric acid (UA) were higher of PAD patients than those of non-PAD patients (t =2.051 9, 3.339 1, P < 0.05); however, there were no significant differences among other metabolic markers (P > 0.05). ② Results of multivariate linear regression analysis: PBG2h, LDL-C and UA were obvious correlation with ABI of posterior tibial artery of lower limb and dorsal pedis artery (partial regression coefficient = -0.231 to -1.010, P < 0.05). ③ Risk factors of CI plus PAD with Logistic regression analysis: Age, smoking history, sum of CI focus (≥3) and LDL-C were independent risk factor of CI plus PAD (OR =1.524-5.422, P < 0.05-0.01). CONCLUSION: ① Levels of serum LDL-C and UA of patients with CI plus PAD are high. ② ABI of lower limbs is correlation with PBG2h, LDL-C and UA. In addition, measuring ABI is beneficial for early diagnosing PAD of lower limbs of patients who have poorly controlled blood glucose, abnormal lipid and poor renal function. ③ Age, LDL-C and sum of CI focus (≥3) are independent risk factors of CI plus PAD. It is of significance for screening non-PAD patients to evaluate risk degrees and prognosis and select therapeutic methods based on ABI measurement. 展开更多
关键词 PAD ABI Risk factors and ankle brachial indexes in cerebral infarction combined with peripheral arterial disease
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Estimation of Global Solar Radiation Using Clearness Index and Cloud Transmittance Factor at Trans-Himalayan Region in Nepal 被引量:1
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作者 Khem N. Poudyal Binod K. Bhattarai +1 位作者 Balkrishna Sapkota Berit Kjeldstad 《Energy and Power Engineering》 2012年第6期415-421,共7页
This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Mete... This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Meter at Lukla (Latitude 26.69oN,Longitude 86.73?E and Altitude 2850 m) in the foothills of the Mt Everest (8850 m high). Monthly and seasonal variations of global solar radiation as well as correlation between clearness index and cloud transmittance factor at Lukla are presented. The annual average daily global solar radiation is about 3.83 kWh/sq·m/day which is sufficient to promote solar active and passive energy technology at high mountain terrain where there is no other viable alternative sources of energy. The maximum and minimum global solar radiation of 5.33 and 2.08 kWh/sq·m/day is recorded in April and September 2010 respectively. The seasonal variation of solar energy is about 2.87 kWh/sq·m/day and 4.83 kWh/sq·m/day in summer and spring respectively which is not in line with the general trend. The coefficient of determination (R2) between cloud transmittance factor (cf) and clearness factor (K) is found to be 0.97. This novel result can be utilized to estimate the global solar radiation at the horizontal surface where K and cf are available. 展开更多
关键词 Global Solar Radiation SEASONAL Variation CLOUD TRANSMITTANCE factor CLEARNESS index Coefficient of Determination High HIMALAYA Region
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Assessing Total Factor Productivity for Soybean Production in China Based on DEA-Malmquist Index: 2005-2017
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作者 Shuguo Yang Jaime Malaga Xiangyu Guo 《American Journal of Plant Sciences》 2020年第1期24-39,共16页
The low and slowly increasing soybean yield restricts the development of soybean production. Accurate measures of total factor productivity (TFP) for soybean production can be helpful in identifying conditions, instit... The low and slowly increasing soybean yield restricts the development of soybean production. Accurate measures of total factor productivity (TFP) for soybean production can be helpful in identifying conditions, institutions or policies that promote soybean production development in China. In this paper, TFP growth for soybean production was estimated for a panel data of 10 major soybean producing provinces from 2005 to 2017. Results reveal that TFP grew at an average rate of 1.3% over the whole period, with technical progress contributing 2.3% and efficiency change providing the other -1.0%. The change of TFP for soybean production over that time, whether increase or decline, was mainly derived by technical change except in three years (2005-2007). Positive TFP growth in the provinces of Liaoning and Inner Mongolia, and negative TFP growth in Hebei and Anhui were mainly driven by efficiency change, specifically scale efficiency change except pure technical efficiency in Liaoning. 展开更多
关键词 TOTAL factor PRODUCTIVITY (TFP) SOYBEAN DEA-MALMQUIST index
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磷指数法——PI(PIndex)的修正及应用 被引量:10
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作者 王丽华 王晓燕 +1 位作者 张志锋 窦培谦 《首都师范大学学报(自然科学版)》 2006年第2期85-88,84,共5页
在农业非点源污染研究中,确定农业非点源污染的关键源区或危险区域是开展有针对性研究和控制农业非点源污染的首要问题之一.磷指数法作为一种评估磷的流失危险性大小的工具,得到了广泛的应用.本文主要介绍了磷指数法的建立及其修正,其... 在农业非点源污染研究中,确定农业非点源污染的关键源区或危险区域是开展有针对性研究和控制农业非点源污染的首要问题之一.磷指数法作为一种评估磷的流失危险性大小的工具,得到了广泛的应用.本文主要介绍了磷指数法的建立及其修正,其中包括三个比较主要的修正,及一些针对本地区实际状况进行的修正.同时本文对该方法在我国的应用提出了建议. 展开更多
关键词 磷指数法 因子 修正 磷流失 潜力
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基于SPSS的城市区域地下水变异Factor Analysis过程 被引量:13
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作者 何兴江 张信贵 易念平 《地质与勘探》 CAS CSCD 北大核心 2006年第1期93-96,共4页
对需要大量运算的统计问题,运用SPSS软件可以快速得到演算结果,从而彻底消除重复而单调的过程,研究人员可更多地专注于统计模型的建立。作者建立了城市建设引发城市区域的地下水缓慢变异的模型,调用SPSS的Factor Analysis过程,对城市区... 对需要大量运算的统计问题,运用SPSS软件可以快速得到演算结果,从而彻底消除重复而单调的过程,研究人员可更多地专注于统计模型的建立。作者建立了城市建设引发城市区域的地下水缓慢变异的模型,调用SPSS的Factor Analysis过程,对城市区域地下水场变异起重要的组分进行提取,以起重要作用的K、Na、Ca、Mg、Fe、Mn组分最少组合来作为评价地下水变异的指标体系。对南宁市区地下水中特征点进行初步定量分析表明,城市区域地下水年变异水平是城市的建设与发展作用的结果,随时间增长变异水平呈增长之势。从历史背景下研究城市区域地下水缓慢变异程度及趋势,对城市地下水演化规律的认识有重要的指导意义。 展开更多
关键词 SPSS软件 地下水环境变异 水化学组分 评价指标 因子分析
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黄土丘陵区县域耕地时空格局变化及驱动因素分析——以天水市武山县为例
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作者 白永刚 刘学录 刘星雨 《国土与自然资源研究》 2025年第1期8-13,共6页
以黄土丘陵区武山县为研究对象,基于土地利用数据,运用变化轨迹分析法、面积加权平均差椭圆和景观格局指数以及土地利用预测模型,探究1990-2018年武山县耕地格局变化特征,判断各要素对其变化的重要程度。结果显示,(1)3个研究时段武山县... 以黄土丘陵区武山县为研究对象,基于土地利用数据,运用变化轨迹分析法、面积加权平均差椭圆和景观格局指数以及土地利用预测模型,探究1990-2018年武山县耕地格局变化特征,判断各要素对其变化的重要程度。结果显示,(1)3个研究时段武山县耕地面积总体呈减少趋势,耕地重心不同时段存在差异,耕地重心先向西南转移再向东南转移。(2)3个研究时段武山县耕地变化都具有减少补充的基本特征,2000年前速率缓慢,2000年后速率加快,耕地减少面积比补充面积多,耕地减少以城关镇和洛门镇为主。(3)3个研究时段武山县耕地图斑呈现出破碎化现象,破碎化程度加剧。(4)3个研究时段武山县耕地发生变化的主要原因可以归纳为政策影响、自然环境因子影响、空间距离要素的影响,而受地理空间要素影响较小。综上,武山县耕地在28年间变化明显,武山县需要贯彻耕地保护政策和可持续发展理念,合理利用耕地。 展开更多
关键词 耕地格局变化 景观格局指数 驱动要素 武山县
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普伐他汀对大鼠坐骨神经压碎损伤功能恢复的影响
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作者 刘赞 安冉 李宝成 《中国组织工程研究》 CAS 北大核心 2025年第5期942-950,共9页
背景:普伐他汀是临床上治疗高胆固醇血症的有效药物,目前发现其在中枢神经损伤的治疗上也能发挥有益作用,然而其机制仍未可知。目的:探究普伐他汀治疗能否加速坐骨神经压碎损伤的功能恢复及其潜在作用机制。方法:将雄性SD大鼠随机分为... 背景:普伐他汀是临床上治疗高胆固醇血症的有效药物,目前发现其在中枢神经损伤的治疗上也能发挥有益作用,然而其机制仍未可知。目的:探究普伐他汀治疗能否加速坐骨神经压碎损伤的功能恢复及其潜在作用机制。方法:将雄性SD大鼠随机分为假手术组(坐骨神经暴露但不损伤+生理盐水灌胃)、阴性对照组(坐骨神经压碎损伤+生理盐水灌胃)、普伐他汀组(坐骨神经压碎损伤+普伐他汀灌胃)。普伐他汀组大鼠术后普伐他汀(5 mg/kg)灌胃治疗1周,其余两组大鼠给予等量生理盐水灌胃。术后观察各组大鼠一般情况;术后第2,4,6,8周末测量各组大鼠的坐骨功能指数;术后8周末测量腓肠肌湿质量比;ELISA法检测血清中炎症细胞因子的水平;组织形态计量学分析坐骨神经有髓神经纤维数目、纤维直径、轴突直径、髓鞘厚度;RT-qPCR检测神经生长因子、脑源性神经营养因子的mRNA表达量,Western blot法检测生长相关蛋白43的蛋白表达量。结果与结论:与阴性对照组相比,普伐他汀组坐骨神经功能指数恢复更快(P<0.05),更接近于假手术组水平,血清中炎症细胞因子肿瘤坏死因子α及白细胞介素6表达更低(P<0.05)且接近假手术组,坐骨神经中神经生长因子、脑源性神经营养因子的mRNA相对表达量增加(P<0.05或P<0.01),坐骨神经中生长相关蛋白43的蛋白相对表达量也明显增加(P<0.05),有髓神经纤维数目增加更多,纤维直径、轴突直径及髓鞘厚度数值更大(P<0.01)且与假手术组更接近。结果说明,普伐他汀的治疗加速了坐骨神经压碎损伤的功能恢复,其可能机制是抑制炎症细胞因子肿瘤坏死因子α及白细胞介素6的表达及促进神经营养因子神经生长因子、脑源性神经营养因子的分泌。 展开更多
关键词 周围神经损伤 普伐他汀 功能恢复 神经营养因子 坐骨神经功能指数
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关于Zp^*分解基S的选取及在Index—calculus算法中的应用
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作者 张金山 张元标 《成都理工大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第1期108-110,共3页
给出循环群Zp*分解基S的选取方法,并由此确定有效生成关系式:αk=∏ti=1pici(其中ci≥0)和βαk=∏ti=1pidi(其中di≥0)。该方法在离散对数体制中,对计算离散对数的Index-calculus算法大有裨益,并通过大量实例验证之。
关键词 分解基 B-smooth index-calculus算法
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基于Three Factor+C模型改进的地形辐射校正方法 被引量:3
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作者 张伟阁 杨辽 +1 位作者 曹良中 贾洋 《国土资源遥感》 CSCD 北大核心 2015年第2期36-43,共8页
地形辐射校正(简称"地形校正")是复杂地形遥感定量化研究的关键环节之一。针对传统的经验地形校正模型存在的不同坡度采用同一校正系数的缺陷,基于简化的Three Factor+C模型,借鉴改进型Minnaert模型中坡度分级的思想,提出了基... 地形辐射校正(简称"地形校正")是复杂地形遥感定量化研究的关键环节之一。针对传统的经验地形校正模型存在的不同坡度采用同一校正系数的缺陷,基于简化的Three Factor+C模型,借鉴改进型Minnaert模型中坡度分级的思想,提出了基于Three Factor+C+坡度的地形校正方法。结果表明,使用Three Factor+C+坡度模型进行地形校正后的遥感图像,其均值、标准差、像元值与光照系数的相关性、阴阳坡光谱辐亮度值、离散指数和同质系数等6个指标均优于参与比较的C模型、SCS模型、Three Factor模型和Three Factor+C模型的对应指标。Three Factor+C+坡度模型有比较完善的物理机制,并较好地消除地形对光谱辐亮度的影响,值得推广。 展开更多
关键词 地形校正 THREE factor+C模型 坡度分级 离散系数 同质系数
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甘肃省农业绿色全要素生产率测算及影响因素研究
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作者 秦博 范国华 《国土与自然资源研究》 2025年第1期59-65,共7页
提升农业绿色全要素生产率对于实现农业可持续发展具有重要的意义。运用SBM-GML指数法对甘肃省各市州2011-2020年的农业绿色全要素生产率及其区域差异进行分析,最后运用Tobit模型对甘肃省农业绿色全要素生产率影响因素进行分析,并在此... 提升农业绿色全要素生产率对于实现农业可持续发展具有重要的意义。运用SBM-GML指数法对甘肃省各市州2011-2020年的农业绿色全要素生产率及其区域差异进行分析,最后运用Tobit模型对甘肃省农业绿色全要素生产率影响因素进行分析,并在此基础上提出相应的对策建议。研究结果显示,(1)甘肃省农业绿色全要素生产率总体呈上升趋势,上升的主要动力来源于技术进步。(2)甘肃省农业绿色全要素生产率存在一定的空间差异性,总体呈现出“西低东高”的分布特点。(3)在甘肃省农业绿色全要素生产率的影响因素中,经济发展水平、城镇化水平、财政支农水平和农业产业结构对甘肃省农业绿色全要素生产率的提升具有显著的正向影响,受灾率对甘肃省农业绿色全要素生产率的提升具有显著的负向影响,且不同区域的农业绿色全要素生产率的影响因素也各不相同。最后,在以上分析的基础上提出了相应的对策建议。 展开更多
关键词 农业绿色全要素生产率 影响因素 SBM-GML指数 TOBIT模型
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Risk factors for tuberculosis after gastrectomy in gastric cancer 被引量:3
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作者 Won Jai Jung Young Mok Park +11 位作者 Joo Han Song Kyung Soo Chung Song Yee Kim Eun Young Kim Ji Ye Jung Moo Suk Park Young Sam Kim Se Kyu Kim Joon Chang Sung Hoon Noh Ji Yeong An Young Ae Kang 《World Journal of Gastroenterology》 SCIE CAS 2016年第8期2585-2591,共7页
AIM: To examine incidence of tuberculosis(TB) in gastrectomy patients and investigate the risk factors for developing TB after gastrectomy in patients with gastric cancer.METHODS: A retrospective cohort study of gastr... AIM: To examine incidence of tuberculosis(TB) in gastrectomy patients and investigate the risk factors for developing TB after gastrectomy in patients with gastric cancer.METHODS: A retrospective cohort study of gastrectomy patients with gastric cancer was performed at a university-affiliated hospital in Seoul, South Korea between January 2007 and December 2009. We reviewed patient medical records and collected data associated with the risk of TB, surgery, and gastric cancer. Standardized incidence ratios(SIRs) of TB were calculated to compare the incidence of TB in gastrectomy patients with that in the general Korean population, and risk factors for TB after gastrectomies were analyzed.RESULTS: Among the 1776 gastrectomy patients, 0.9%(16/1776) developed post-gastrectomy TB, with an incidence of 223.7 cases per 100000 patients per year. The overall incidence of TB in gastrectomy patients, adjusted by sex and age, was significantly higher thanthat in the general population(SIR = 2.22, 95%CI: 1.27-3.60). Previous TB infection [odds ratio(OR) = 7.1, P < 0.001], lower body mass index(BMI)(kg/m2; OR = 1.21, P = 0.043) and gastrectomy extent(total gastrectomy vs subtotal gastrectomy)(OR = 3.48, P = 0.017) were significant risk factors for TB after gastrectomy in a multivariate analysis.CONCLUSION: TB incidence after gastrectomy is higher than that in the general population. Previous TB infection, lower BMI, and total gastrectomy are risk factors for TB after gastrectomy in patients with gastric cancer. 展开更多
关键词 TUBERCULOSIS GASTRECTOMY BODY mass index Risk factor GASTRIC cancer
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Contamination and Ecological Risk Assessment of Heavy Metal in the Sediment of Turag River, Bangladesh: An Index Analysis Approach 被引量:5
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作者 Zoynab Banu Md. Shariful Alam Chowdhury +1 位作者 Md. Delwar Hossain Ken’ichi Nakagami 《Journal of Water Resource and Protection》 2013年第2期239-248,共10页
Encroachment, disposal of untreated domestic and industrial wastewater and dumping of solid wastes have degraded the overall quality of the river Turag, which is located in Dhaka—the Capital City of Bangladesh. The p... Encroachment, disposal of untreated domestic and industrial wastewater and dumping of solid wastes have degraded the overall quality of the river Turag, which is located in Dhaka—the Capital City of Bangladesh. The present study investigated the extent of pollution of sediments of this river and analyzed the regional variability for the concentrations of Cr, Pb, Zn, Cu and Cd—all of concern because of their potential toxicity, using atomic absorption spectrophotometer. As per US EPA sediment quality guideline, metal concentrations ranged between Cd: 0.00 - 0.80, Cr: 32.00 - 75.50, Cu: 46.30 - 60.00, Pb: 28.30 - 36.40, and Zn: 94.60 - 190.10 mg/kg in the Turag river sediments. Cr, Cu, Zn belongs to moderately to highly polluted, Pb and Cd belongs to not polluted for Turag river. The heavy metals contamination in the sediments were also evaluated by applying Index of geo-accumulation (Igeo), contamination factor (Cf), pollution load index (PLI) etc. Toxicity characteristics leaching procedure (TCLP) test (US EPA 1311) for sediment samples have been performed also for metals (Pb, Cd, Cr, Cu and Zn) to determine the readily toxicity level of heavy metals. Sieve analysis of sediment performed in this study to determine the physical characteristic of sediment samples. The metal concentrations are well below the regulated level as per US EPA. This index can be complemented with the contamination index, which allows more site-specific and accurate information on contaminant levels. If the aim of work on contamination evaluation is to assess the overall contamination of a study area, the indices are highly appropriate. 展开更多
关键词 Heavy Metal TCLP Test SEDIMENT Geo-Accumulation index Ecological Risk index CONTAMINATION factor Turag RIVER etc.
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The Impacts of Mosquito Density and Meteorological Factors on Dengue Fever Epidemics in Guangzhou, China, 2006-2014: a Time-series Analysis 被引量:12
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作者 SHEN Ji Chuan LUO Lei +4 位作者 LI Li JING Qin Long OU Chun Quan YANG Zhi Cong CHEN Xiao Guang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第5期321-329,共9页
Objective To explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China. Methods The monthly number of DF cases, Breteau Index ... Objective To explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China. Methods The monthly number of DF cases, Breteau Index (BI), and meteorological measures during 2006-2014 recorded in Guangzhou, China, were assessed. A negative binomial regression model was used to evaluate the relationships between BI, meteorological factors, and the monthly number of DF cases. Results A total of 39,697 DF cases were detected in Guangzhou during the study period. DF incidence presented an obvious seasonal pattern, with most cases occurring from June to November. The current month's BI, average temperature (Tare), previous month's minimum temperature (Train), and Tare were positively associated with DF incidence. A threshold of 18.25℃ was found in the relationship between the current month's Tmin and DF incidence. Conclusion Mosquito density, Tove, and Tmin play a critical role in DF transmission in Guangzhou. These findings could be useful in the development of a DF early warning system and assist in effective control and prevention strategies in the DF epidemic. 展开更多
关键词 Breteau index Dengue fever Meteorological factors Negative binomial regression model
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Climatic Characteristics of Hail and Risk Zoning of Its Disaster Factor in Anhui Province 被引量:1
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作者 Huayang Wen Hong Tian +2 位作者 Weian Tang Yanyu Lu Rong Wu 《Meteorological and Environmental Research》 CAS 2013年第8期32-35,38,共5页
[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chi... [ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chinese Meteorologica/Disaster Dictionary (1951 to 2005) and The Yearbook of Meteorological Disaster in Anhui Province (2006 to 2009), we discussed the climatic characteristic and dsk zoning of hail disaster in Anhui Province. [Result] The hail days exhibited significant interdecadal variability, and it had a significant negative correlation with annual mean minimum temperature. The hail usually occurred from March to August, most frequently in June but less in autumn and winter. It most likely took place from aftemoon to sunset. The spatial distribution showed that the hail occurred more in northeast of Huaibei, south of Dabie Mountain and some areas of Huangshan Mountain, but less in Jianghuai region. The index of hail intensity was defined by three factors, the diameter, duration and gust grade, and the percentile method was used to grade the intensity of the hail disaster. This work provided a possibility for quantitative assessment of the intensity of hail disaster. The results of hail disaster risk zoning in Anhui Province showed that high dsk zones were concentrated in northeast of Huaibei, and low risk zones were mainly in south of Huaihe River. Finally, vedfied by historic disaster, it showed that the results of risk zoning had a certain rationality and feasibility. Conclusion The research could provide reference basis for hail disaster defense and assessment. 展开更多
关键词 HAIL Climatic charactedstics Hail intensity index Disaster factor Risk zoning China
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A body mass index ≥25 kg/m2 is associated with a poor prognosis in patients with acute pancreatitis: a study of Japanese patients 被引量:9
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作者 Tsukasa Ikeura Kota Kato +5 位作者 Makoto Takaoka Masaaki Shimatani Masanobu Kishimoto Kenichiro Nishi Shuji Kariya Kazuichi Okazaki 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2017年第6期645-651,共7页
BACKGROUND:In Asian population, there is limited infor mation on the relevance between obesity and poor outcomes in acute pancreatitis(AP). The objective of this study was to examine the clinical impact of obesity bas... BACKGROUND:In Asian population, there is limited infor mation on the relevance between obesity and poor outcomes in acute pancreatitis(AP). The objective of this study was to examine the clinical impact of obesity based on body mass index(BMI) on prognosis of AP in Japanese patients.METHODS:A total of 116 patients with AP were enrolled in this study. Univariate and multivariate logistic regression analyses were performed to examine relations between BMI and patients’ outcomes. Additionally, to investigate whether including obesity as a prognostic factor improved the predic tive accuracy of a Japanese prognostic factor score(PF score)a receiver-operating characteristic(ROC) curve analysis of mortality was conducted.RESULTS:Multiple logistic regression analyses revealed that BMI ≥25 kg/m2was associated with a significant higher mor tality [odds ratio(OR)=15.8; 95% confidence interval(CI):1.1-227; P=0.043]. The area under the ROC curve(AUC) for the combination of PF score and BMI ≥25 kg/m2(AUC=0.881;95% CI:0.809-0.952) was higher than that for the PF score alone(AUC=0.820; 95% CI:0.713-0.927)(P=0.034).CONCLUSIONS:The negative impact of a high BMI on the prognosis of AP was confirmed in a Japanese population Including BMI ≥25 kg/m2 as an additional parameter to PF score enhanced the predictive value of the PF score for AP-related mortality. 展开更多
关键词 acute pancreatitis OBESITY body mass index severity criteria prognostic factor score
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Human development index is associated with mortality-to-incidence ratios of gastrointestinal cancers 被引量:3
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作者 Qi-Da Hu Qi Zhang +2 位作者 Wei Chen Xue-Li Bai Ting-Bo Liang 《World Journal of Gastroenterology》 SCIE CAS 2013年第32期5261-5270,共10页
AIM:To identify the role of human development in the incidence and mortality rates of gastrointestinal cancers worldwide.METHODS:The age-standardized incidence and mortality rates for gastrointestinal cancers,includin... AIM:To identify the role of human development in the incidence and mortality rates of gastrointestinal cancers worldwide.METHODS:The age-standardized incidence and mortality rates for gastrointestinal cancers,including cancers of the esophagus,stomach,pancreas,liver,gallbladder,and colorectum,were obtained from the GLOBOCAN 2008 database and United States Cancer Statistics(USCS)report.The human development index(HDI)data were calculated according to the 2011 Human Development Report.We estimated the mortality-toincidence ratios(MIRs)at the regional and national levels,and explored the association of the MIR with development levels as measured by the HDI using a modified"drug dose to inhibition response"model.Furthermore,countries were divided into four groups according to the HDI distribution,and the MIRs of the four HDI groups were compared by one-way ANOVA followed by the Tukey-Kramer post-hoc test.Statespecific MIRs in the United States were predicted from the estimated HDI using the fitted non-linear model,and were compared with the actual MIRs calculated from data in the USCS report.RESULTS:The worldwide incidence and mortality rates of gastrointestinal cancers were as high as 39.4and 54.9 cases per 100000 individuals,respectively.Linear and non-linear regression analyses revealed an inverse correlation between the MIR of gastrointestinal cancers and the HDI at the regional and national levels(<0;P=0.0028 for regional level and<0.0001 for national level,ANOVA).The MIR differed significantly among the four HDI areas(very high HDI,0.620±0.033;high HDI,0.807±0.018;medium HDI,0.857±0.021;low HDI,0.953±0.011;P<0.001,oneway ANOVA).Prediction of the MIRs for individual United States states using best-fitted non-linear models showed little deviation from the actual MIRs in the United States.Except for 28 data points(9.93%of282),the actual MIRs of all gastrointestinal cancers were mostly located in the prediction intervals via the best-fit non-linear regression models.CONCLUSION:The inverse correlation between HDI and MIR demonstrates that more developed areas have a relatively efficacious healthcare system,resulting in low MIRs,and HDI can be used to estimate the MIR. 展开更多
关键词 GASTROINTESTINAL NEOPLASMS Mortality-toincidence ratio Human development index Healthcare DISPARITIES SOCIOECONOMIC factors
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Correlation of serum albumin and prognostic nutritional index with outcomes following pancreaticoduodenectomy 被引量:7
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作者 Narongsak Rungsakulkij Pongsatorn Tangtawee +3 位作者 Wikran Suragul Paramin Muangkaew Somkit Mingphruedhi Suraida Aeesoa 《World Journal of Clinical Cases》 SCIE 2019年第1期28-38,共11页
BACKGROUND Pancreaticoduodenectomy(PD) is a complex surgical procedure with a high morbidity rate. The serious complications are major risk factors for poor longterm surgical outcome. Studies have reported an associat... BACKGROUND Pancreaticoduodenectomy(PD) is a complex surgical procedure with a high morbidity rate. The serious complications are major risk factors for poor longterm surgical outcome. Studies have reported an association between early postoperative prognostic nutritional index(PNI) and prediction of severe complications after abdominal surgery. However, there have been no studies on the use of early postoperative PNI for predicting serious complications following PD.AIM To analyze the risk factors and early postoperative PNI for predicting severe complications following PD.METHODS We retrospectively analyzed 238 patients who underwent PD at our hospital between January 2007 and December 2017. The postoperative complications were classified according to the Dindo-Clavien classification. Grade Ⅲ-Ⅴ postoperative complications were classified as serious. The risk factors for serious complications were analyzed by univariate analysis and multivariate logistic regression analysis.RESULTS Overall complications were detected in 157 of 238 patients(65.9%) who underwent PD. The grade Ⅲ-Ⅴ complication rate was 26.47%(63/238 patients).The mortality rate was 3.7%(9/238 patients). Multivariate logistic regression analysis revealed that preoperative serum albumin [odds ratio(OR): 0.883, 95%confidence interval(CI): 0.80-0.96; P < 0.01] and PNI on postoperative day 3 <40.5(OR: 2.77, 95%CI: 1.21-6.38, P < 0.05) were independent factors associated with grade Ⅲ-Ⅴ postoperative complications.CONCLUSION Perioperative albumin is an important factor associated with serious complications following PD. Low early postoperative PNI(< 40.5) is a predictor for serious complications. 展开更多
关键词 POSTOPERATIVE complications PANCREATECTOMY Serum ALBUMIN Risk factors PROGNOSTIC NUTRITIONAL index
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An empirical study on evaluation indexes of scientific research achievements in nursing 被引量:6
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作者 Jin-Lian Cheng Xi Tan 《Frontiers of Nursing》 CAS 2018年第1期35-41,共7页
Objective: The purpose of this empirical study was to investigate the evaluation indexes of nursing research results and to provide references for the optimization of nursing research results and their clinical applic... Objective: The purpose of this empirical study was to investigate the evaluation indexes of nursing research results and to provide references for the optimization of nursing research results and their clinical applications.Methods: A total of 150 clinical nursing studies were randomly selected, the clinical applications of their results were investigated,and the results were evaluated using the evaluation indexes of nursing research achievements.Results: The results of 101 clinical nursing studies were promoted through their application, accounting for 82.79%, but they were mostly promoted and applied in small areas. When the evaluation indexes of nursing research results were used to evaluate the results, the scores for the applied results were higher than those of unapplied results, and the difference was statistically significant(P < 0.05). Considering the levels of the results, the scores of the results of studies at the national level were higher than those of studies at the municipal and hospital levels; the scores of the results of studies at the provincial level were higher than those at the hospital level; and the scores of the results of originally innovative studies were higher than those of partially innovative studies. The differences were statistically significant(P < 0.05). In terms of overall scores, the scores of the results at the provincial level were higher than those at the hospital level, and the difference was statistically significant(P < 0.05).Conclusions: The evaluation indexes of nursing research results in this study can scientifically and effectively evaluate the level,value, and effectiveness of the nursing research results and can promote the clinical application of the optimized results. 展开更多
关键词 NURSING CLINICAL study results evaluation index PROMOTION by application influencing factorS
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