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矽卡岩单轴循环加卸载试验及声发射特性研究 被引量:56
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作者 徐速超 冯夏庭 陈炳瑞 《岩土力学》 EI CAS CSCD 北大核心 2009年第10期2929-2934,共6页
利用MTS岩石力学试验系统和PAC声发射信号采集系统,研究了单轴循环加卸载作用下矽卡岩强度变化及声发射特征。在矽卡岩循环加卸载过程中,若加载过程中岩样没有明显局部破坏,则随着循环次数的增加,弹性模量逐渐增大,岩样强度略有提高;若... 利用MTS岩石力学试验系统和PAC声发射信号采集系统,研究了单轴循环加卸载作用下矽卡岩强度变化及声发射特征。在矽卡岩循环加卸载过程中,若加载过程中岩样没有明显局部破坏,则随着循环次数的增加,弹性模量逐渐增大,岩样强度略有提高;若加载过程中岩样内部已经出现明显的局部破坏,产生了不可恢复的宏观裂纹,则循环加卸载会促进宏观裂纹层面间的滑移,从而加速岩样失稳破坏。矽卡岩在单轴压缩作用下声发射曲线大体可分为压密、弹性、塑性、峰后屈服4个阶段,并伴随有不同的声发射情况。此外,矽卡岩在循环加卸载作用下具有反凯塞效应,并且随着加卸载循环次数的增加,费拉西蒂比逐渐变小;岩样卸载阶段仍然有大量声发射产生。 展开更多
关键词 矽卡岩 单轴压缩 声发射 振铃数 绝对能量 循环加卸载
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Comparison of total splenic artery embolization and partial splenic embolization for hypersplenism 被引量:23
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作者 Xin-Hong He Jian-Jian Gu +5 位作者 Wen-Tao Li Wei-Jun Peng Guo-Dong Li Sheng-Ping Wang Li-Chao Xu Jun Ji 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第24期3138-3144,共7页
AIM:To evaluate whether total splenic artery embolization(TSAE) for patients with hypersplenism delivers better long-term outcomes than partial splenic embolization(PSE).METHODS:Sixty-one patients with hypersplenism e... AIM:To evaluate whether total splenic artery embolization(TSAE) for patients with hypersplenism delivers better long-term outcomes than partial splenic embolization(PSE).METHODS:Sixty-one patients with hypersplenism eligible for TSAE(n = 27,group A) or PSE(n = 34,group B) were enrolled into the trial,which included clinical and computed tomography follow-up.Data on technical success,length of hospital stay,white blood cell(WBC) and platelet(PLT) counts,splenic volume and complications were collected at 2 wk,6 mo,and 1,2,3,4 years postoperatively.RESULTS:Both TSAE and PSE were technically successful in all patients.Complications were significantly fewer(P = 0.001),and hospital stay significantly shorter(P = 0.007),in group A than in group B.Postprocedure WBC and PLT counts in group A were significantly higher than those in group B from 6 mo to 4 years(P = 0.001),and post-procedure residual splenic volume in group A was significantly less than that observed in group B at 1,2,3 and 4 years post-procedure(P = 0.001).No significant differences were observed in red blood cell counts and liver function parameters between the two groups following the procedure.CONCLUSION:Our results indicate that TSAE for patients with hypersplenism not only delivers a better longterm outcome,but is also associated with lower complication rates and a shorter hospital stay than PSE. 展开更多
关键词 EMBOLIZATION HYPERSPLENISM COMPLICATIONS White cell counts Platelet counts
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附属刑法的立法模式问题探讨 被引量:18
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作者 孟庆华 《法学论坛》 CSSCI 北大核心 2010年第3期76-81,共6页
附属刑法具有"由国家立法机关制定"、基本内容是"犯罪与刑罚的行为规范"与"非刑事法律中附加制定"等三个基本构成特征。我国附属刑法目前主要有"笼统式"与"依照式"两种立法模式。&qu... 附属刑法具有"由国家立法机关制定"、基本内容是"犯罪与刑罚的行为规范"与"非刑事法律中附加制定"等三个基本构成特征。我国附属刑法目前主要有"笼统式"与"依照式"两种立法模式。"笼统式"规定一般表述为"构成犯罪的,依法追究刑事责任","依照式"规定一般表述为"依照刑法追究刑事责任",这些表述由于缺乏必要的明确性,因而缺乏实际的可操作性。解决我国附属刑法立法模式存在的问题,根本方式就是制定创制性附属刑法。 展开更多
关键词 附属刑法 罪状 法定刑
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五十种植物的染色体计数 被引量:14
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作者 陈升振 陈忠毅 +3 位作者 黄向旭 黄少甫 王雅琴 赵治芬 《广西植物》 CAS CSCD 北大核心 1990年第1期33-37,001,T002,共7页
本文对种子植物32科44属的50种(包括变种)作了染色体计数观察,其中16种9变种是染色体计数的新记录。
关键词 染色体计数 种子植物 标本
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铝合金疲劳裂纹扩展声发射监测 被引量:15
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作者 朱荣华 刚铁 《焊接学报》 EI CAS CSCD 北大核心 2013年第3期29-32,114,共4页
采用声发射(acoustic emission,AE)技术对7N01铝合金单边缺口三点弯曲试样不同应力比、不同峰值载荷下疲劳裂纹扩展过程中声发射信号进行了监测,建立了裂纹扩展速率、声发射计数(count)与应力强度因子之间的关系.结果表明,大部分的声发... 采用声发射(acoustic emission,AE)技术对7N01铝合金单边缺口三点弯曲试样不同应力比、不同峰值载荷下疲劳裂纹扩展过程中声发射信号进行了监测,建立了裂纹扩展速率、声发射计数(count)与应力强度因子之间的关系.结果表明,大部分的声发射信号主要产生于疲劳循环载荷的低应力阶段,这主要是低应力阶段的声发射活动主要与裂纹尖端的塑性变形和裂纹闭合现象有关,声发射计数与应力强度因子之间呈指数增长的关系.基于所建立的声发射计数率与裂纹扩展速率的关系,可以预测疲劳损伤结构的剩余寿命. 展开更多
关键词 铝合金 声发射 疲劳 计数
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Numerical simulation of soldered joints and reliability analysis of PLCC components with J-shape leads 被引量:13
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作者 张亮 薛松柏 +2 位作者 卢方焱 韩宗杰 王俭辛 《China Welding》 EI CAS 2008年第2期37-41,共5页
This paper deals with a study on SnPb and lead-free soldered joint reliability of PLCC devices with different lead counts under three kinds of temperature cycle profiles, which is based on non-linear finite element me... This paper deals with a study on SnPb and lead-free soldered joint reliability of PLCC devices with different lead counts under three kinds of temperature cycle profiles, which is based on non-linear finite element method. By analyzing the stress of soldered joints, it is found that the largest stress is at the area between the soldered joints and the leads, and analysis results indicate that the yon Mises stress at the location slightly increases with the increase of lead counts. For PLCC with 84 leads the soldered joints was modeled for three typical loading (273 -398 K, 218 -398 K and 198 -398 K) in order to study the influence of acceleration factors on the reliability of soldered joints. And the estimation of equivalent plastic strain of three different lead-free solder alloys ( Sn3.8AG0. 7Cu, Sn3.5Ag and Sn37Pb ) was also carried out. 展开更多
关键词 finite element method reliability lead counts equivalent plastic strain
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Bibliometrics: tracking research impact by selecting Lhe appropriate metrics 被引量:13
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作者 Ashok Agarwal Damayanthi Durairajanayagam +18 位作者 Sindhuja Tatagari Sandro C Esteves Avi Harlev Ralf Henkel Shubhadeep Roychoudhury Sheryl Homa Nicolas Garrido Puchalt Ranjith Ramasamy Ahmad Majzoub Kim Dao Ly Eva Tvrda Mourad Assidi Kavindra Kesai Reecha Sharma Saleem Banihani Edmund Ko Muhammad Abu-Elmagd Jaime Gosalvez Asher Bashiri 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第2期296-309,J0008,共15页
Traditionally, the success of a researcher is assessed by the number of publications he or she publishes in peer-reviewed, indexed, high impact journals. This essential yardstick, often referred to as the impact of a ... Traditionally, the success of a researcher is assessed by the number of publications he or she publishes in peer-reviewed, indexed, high impact journals. This essential yardstick, often referred to as the impact of a specific researcher, is assessed through the use of various metrics. While researchers may be acquainted with such matrices, many do not know how to use them to enhance their careers. In addition to these metrics, a number of other factors should be taken into consideration to objectively evaluate a scientist's profile as a researcher and academician. Moreover, each metric has its own limitations that need to be considered when selecting an appropriate metric for evaluation. This paper provides a broad overview of the wide array of metrics currently in use in academia and research. Popular metrics are discussed and defined, including traditional metrics and article-level metrics, some of which are applied to researchers for a greater understanding of a particular concept, including varicocete that is the thematic area of this Special Issue of Asian Journal of Andrology. We recommend the combined use of quantitative and qualitative evaluation using judiciously selected metrics for a more objective assessment of scholarly output and research impact. 展开更多
关键词 article-level metrics BIBLIOMETRICS citation counts H-INDEX impact factor research databases research impact research productivity traditional metrics
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Rock burst proneness prediction by acoustic emission test during rock deformation 被引量:13
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作者 张志镇 高峰 尚晓吉 《Journal of Central South University》 SCIE EI CAS 2014年第1期373-380,共8页
Rock burst is a severe disaster in mining and underground engineering,and it is important to predict the rock burst risk for minimizing the loss during the constructing process.The rock burst proneness was connected w... Rock burst is a severe disaster in mining and underground engineering,and it is important to predict the rock burst risk for minimizing the loss during the constructing process.The rock burst proneness was connected with the acoustic emission(AE) parameter in this work,which contributes to predicting the rock burst risk using AE technique.Primarily,a rock burst proneness index is proposed,and it just depends on the heterogeneous degree of rock material.Then,the quantificational formula between the value of rock burst proneness index and the accumulative AE counts in rock sample under uniaxial compression with axial strain increases is developed.Finally,three kinds of rock samples,i.e.,granite,limestone and sandstone are tested about variation of the accumulative AE counts under uniaxial compression,and the test data are fitted well with the theoretic formula. 展开更多
关键词 rock mechanics rock burst proneness PREDICTION accumulative acoustic emission counts Weibull statistical distribution
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中日新数学教科书中的“勾股定理” 被引量:11
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作者 朱哲 张维忠 《数学教育学报》 北大核心 2011年第1期84-87,共4页
由于勾股定理在数学及数学教育中的特殊地位,它几乎是全世界的中学数学课程都要介绍的内容.从教科书内容的广度和深度来看,《中学数学》最难,《数学》次之,New Mathematics Counts最易;《中学数学》和New Mathematics Counts对勾... 由于勾股定理在数学及数学教育中的特殊地位,它几乎是全世界的中学数学课程都要介绍的内容.从教科书内容的广度和深度来看,《中学数学》最难,《数学》次之,New Mathematics Counts最易;《中学数学》和New Mathematics Counts对勾股定理的发现和证明做了弱化处理;《数学》重视对勾股定理的证明,向学生展现了多元文化背景下的数学内容;3种教科书对定理的应用都很重视,都给出了一定数量的例题和习题. 展开更多
关键词 数学教科书 勾股定理 中学数学 NEW MATHEMATICS counts 比较
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Predictive value of immune cell counts and neutrophil-to-lymphocyte ratio for 28-day mortality in patients with sepsis caused by intra-abdominal infection 被引量:10
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作者 Shuangqing Liu Yuxuan Li +2 位作者 Fei She Xiaodong Zhao Yongming Yao 《Burns & Trauma》 SCIE 2021年第1期573-583,共11页
Background:The current study aimed to evaluate the value of immune cell counts and neutrophilto-lymphocyte ratio(NLR)when attempting to predict 28-day mortality.Methods:We conducted an observational retrospective stud... Background:The current study aimed to evaluate the value of immune cell counts and neutrophilto-lymphocyte ratio(NLR)when attempting to predict 28-day mortality.Methods:We conducted an observational retrospective study that included consecutive septic patients.Severity scores on the first day and peripheral circulating immune cell counts(at day 1,day 3,day 5 and day 7 of admission)were collected during each patient’s emergency intensive care unit stay.We assessed the associations of peripheral circulating immune cell counts and NLR with the severity of illness.The relationships between 28-day mortality and peripheral circulating immune cell counts and NLR with were evaluated using Cox proportional cause-specific hazards models.Results:A total of 216 patients diagnosed with sepsis caused by IAI were enrolled.The lymphocyte counts(days 1,3,5 and 7)and monocyte counts(days 3,5 and 7)were significantly lower in nonsurvivors(n=72)than survivors(n=144).The NLR values at each time point were significantly higher in non-survivors.The day 1 lymphocyte counts,as well as the monocyte counts,were significantly lower in the highest-scoring group,when stratified by the Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores,than in the other groups(p<0.05).The day 1 NLR was significantly higher in the highest-scoring group than in the other groups(p<0.05).The day 5 and day 7 lymphocyte counts,day 3 and day 7 monocyte counts and day 7 NLR were significant predictors of 28-day mortality in the Cox proportional hazards models(day 5 lymphocyte count:hazard ratio,0.123(95%CI,0.055–0.279),p<0.001;day 7 lymphocyte count:hazard ratio,0.115(95%CI,0.052–0.254),p<0.001;day 3 monocyte count:hazard ratio,0.067(95%CI,0.005–0.861),p=0.038;day 7 monocyte count:hazard ratio,0.015(95%CI,0.001–0.158),p<0.001;day 7 NLR:hazard ratio,0.773(95%CI,0.659–0.905),p=0.001).Conclusions The results showed that circulating lymphocytes and monocytes were dramatically decreased within 7 days in non-survivor 展开更多
关键词 Lymphocyte counts Monocyte counts Predictive value MORTALITY SEPSIS Intra-abdominal infection
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Postoperative Low Absolute Lymphocyte Counts may Predict Poor Outcomes of Hepatocellular Carcinoma After Liver Resection 被引量:9
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作者 Ming Wang Chuan Li +2 位作者 Tian-Fu Wen Wei Peng Li-Ping Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第5期536-541,共6页
Background:The absolute lymphocyte counts (ALCs) have been reported as one of worse prognostic factors for hepatocellular carcinoma (HCC) patient after liver transplantation.The aim of this study was to assess th... Background:The absolute lymphocyte counts (ALCs) have been reported as one of worse prognostic factors for hepatocellular carcinoma (HCC) patient after liver transplantation.The aim of this study was to assess the influence of ALCs on the outcomes of patients with hepatitis B virus (HBV)-related HCC within the Milan criteria following liver resection.Methods:Data of patients with HCC within the Milan criteria who received liver resection between January 2007 and June 2013 were reviewed,and perioperative ALCs were carefully monitored.All potential risk factors were statistically analyzed by uni-and multi-variate analyses.The receiver operating characteristic (ROC) curve was used to determine the optimalALCs cut-offvalue to predict HCC recurrence after liver resection.Results:A total of 221 patients were enrolled in the current study.During the follow-up period,106 patients experienced recurrence,and 38 patients died.Multivariate analysis suggested microvascular invasion (MVI),a tumor grade ≥2,and a low postoperative ALCs in the 1^st postoperative month increased the incidence of postoperative recurrence,besides,MVI,intraoperative transfusion,and a low postoperative ALCs in the 1 st postoperative month were associated with poor overall survival (OS).An ROC analysis showed that a cut-offvalue of 1.5 × 10^9/L for ALCs in the 1^st postoperative month predicted postoperative recurrence.The 5-year recurrence-free survival (RFS) and OS rates of patients with low postoperative ALCs were 34.5% and 64.8%,respectively,which were significantly lower than those of patients with high postoperative ALC (58.5% for RFS and 86.5% for OS).Conclusion:Low ALCs in the 1^st postoperative month may be associated with high recurrence incidence and poor OS for patients with HBV-related HCC within the Milan criteria after liver resection. 展开更多
关键词 Absolute Lymphocyte counts Hepatocellular Carcinoma Liver Resection OUTCOME
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单轴加卸载条件下岩盐变形过程能量和声发射特征研究 被引量:9
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作者 邓朝福 刘建锋 +3 位作者 徐慧宁 边宇 吴池 向高 《四川大学学报(工程科学版)》 CSCD 北大核心 2017年第S2期150-156,共7页
利用MTS815 Flex Test GT岩石力学试验系统及声发射(AE)实时监测系统,对取自平顶山和淮安两处矿井的纯盐岩进行单抽加卸载试验,得到岩盐的应力-应变加卸载曲线、声发射振铃计数率和能量率曲线,并从能量与声发射的角度研究纯岩盐变形破... 利用MTS815 Flex Test GT岩石力学试验系统及声发射(AE)实时监测系统,对取自平顶山和淮安两处矿井的纯盐岩进行单抽加卸载试验,得到岩盐的应力-应变加卸载曲线、声发射振铃计数率和能量率曲线,并从能量与声发射的角度研究纯岩盐变形破坏过程的基本特征。研究表明:岩盐单轴加卸载条件下,弹性变形阶段很短,屈服过程产生很大的塑形变形,且峰后的变形过程没有应力的急剧下降,整个试验过程中加卸、载之间滞回环面积很微小。在整个试验过程中,弹性应变能所占比例非常小;盐岩单轴加卸载变形破坏过程中,其耗散能随应变一直增加,且增长率递增,而当应力接近峰值时,增长率趋于恒定,耗散能曲线开始呈线性增长;弹性应变能在峰前一直增加,且增长率递减,在峰值处达到最大值,峰后开始下降。岩盐在试验初始阶段振铃计数率与能量率大量产生,后在屈服阶段呈现下降进入稳定发展期,直到峰值处,出现一个累计振铃计数和累计能量曲线的拐点,峰后以一个更高的速率稳定且呈现阶梯状发展。本文对于盐岩储气库的水溶开挖和采气过程中逐渐卸载的应力环境施工过程有一定的实际指导意义。 展开更多
关键词 岩盐 滞回环 耗散能 弹性应变能 振铃计数
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Reduction effect of bacterial counts by preoperative saline lavage of the stomach in performing laparoscopic and endoscopic cooperative surgery 被引量:9
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作者 Hirohito Mori Hideki Kobara +9 位作者 Takaaki Tsushimi Shintaro Fujihara Noriko Nishiyama Tae Matsunaga Maki Ayaki Tatsuo Yachida Joji Tani Hisaaki Miyoshi Asahiro Morishita Tsutomu Masaki 《World Journal of Gastroenterology》 SCIE CAS 2014年第42期15763-15770,共8页
AIM: To investigate the effects of gastric lavage with 2000 mL of saline in laparoscopic and endoscopic cooperative surgery.
关键词 Laparoscopic and endoscopic cooperative surgery Systemic gastric lavage Disinfection Bacterial counts Duodenal balloon occlusion
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Impact of baseline CD4^+ T cell counts on the efficacy of nevirapinebased highly active antiretroviral therapy in Chinese HIV/AIDS patients: a prospective, multicentric study 被引量:7
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作者 LIU Zheng-yin GUO Fu-ping HAN Yang QIU Zhi-feng ZUO Ling-yan LI Yan-ling LI Tai-sheng 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第20期2497-2502,共6页
Background CD4^+T cell counts have been used as the indicator of human immunodeficiency virus type 1 (HIV-1) disease progression and thereby to determine when to start highly active antiretroviral therapy (HAART)... Background CD4^+T cell counts have been used as the indicator of human immunodeficiency virus type 1 (HIV-1) disease progression and thereby to determine when to start highly active antiretroviral therapy (HAART). Whether and how the baseline CD4^+T cell count affects the immunological and viral responses or adverse reactions to nevirapine (NVP)-containing HAART in Chinese HIV-1 infected adults remain to be characterized. Methods One hundred and ninety-eight HIV-seropositive antiretroviral therapy (ART)-naive subjects were enrolled into a prospective study from 2005 to 2007. Data were analyzed by groups based on baseline CD4^+T cell counts either between 100-200 cells/μl or 201-350 cells/μl. Viral responses, immunologic responses and adverse events were monitored at baseline and at weeks 4, 12, 24, 36, 52, 68, 84, 100. Results Eighty-six and 112 subjects ranged their CD4^+T cell counts 100-200 cells/μl and 201-350 cells/μl, respectively. The pre-HAART viral load in CD4 201-350 cells/μl group was significantly lower than that in CD4 100-200 cells/μl group (P=0.000). After treatment, no significant differences were observed between these two groups either in the plasma viral load (pVL) or in the viral response rate calculated as the percentage of pVL less than 50 copies/ml or less than 400 copies/ml. The CD4^+T cell counts were statistically higher in the 201-350 group during the entire follow-ups (P 〈0.01) though CD4^+ T cell count increases were similar in these two groups. After 100-week treatment, the median of CD4^+ T cell counts were increased to 331 cells/μl for CD4 100-200 cells/μl group and to 462 cells/μl for CD4 201-350 cells/μl group. Only a slightly higher incidence of nausea was observed in CD4 201-350 cells/μl group (P=0.05) among all adverse reactions, including rash and liver function abnormality. Conclusions The pVLs and viral response rates are unlikely to be associated with the baseline CD4^+T cell counts. Initiating HAART in Chinese H 展开更多
关键词 human immunodeficiency virus acquired immunodeficiency syndrome highly active antiretroviral therapy CD4^+ T cell counts NEVIRAPINE
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Semen analysis from an epidemiologic perspective 被引量:7
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作者 Jens Peter Ellekilde Bonde 《Asian Journal of Andrology》 SCIE CAS CSCD 2010年第1期91-94,共4页
The fifth edition of the World Health Organization (WHO) manual for semen analysis includes for the first time reference values for human semen characteristics. This paper considers whether such values will help to ... The fifth edition of the World Health Organization (WHO) manual for semen analysis includes for the first time reference values for human semen characteristics. This paper considers whether such values will help to resolve the intensely debated data indicating temporal and geographical shifts in sperm counts and hypotheses that anthropogenic activities that result in the release of chemicals into the environment are detrimental to male reproductive health. The reasons that these reference values will not fulfil these purposes are also explained. Although established reference values for semen characteristics are of limited value in analytical epidemiologic research, the WHO guidelines are of utmost importance for supporting the development of appropriate research protocols. Moreover, in spite of its limitations, semen analysis is still a useful research tool in epidemiological research, and no superior alternatives are on the horizon. 展开更多
关键词 DECLINE EPIDEMIOLOGY reference values RESEARCH semen analysis sperm counts
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Empirical Bayesian Approach to Testing Homogeneity of Several Means of Inflated Poisson Distributions (IPD)
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作者 Mohamed M. Shoukri Maha Aleid 《Open Journal of Statistics》 2023年第3期285-299,共15页
Objectives: We introduce a special form of the Generalized Poisson Distribution. The distribution has one parameter, yet it has a variance that is larger than the mean a phenomenon known as “over dispersion”. We dis... Objectives: We introduce a special form of the Generalized Poisson Distribution. The distribution has one parameter, yet it has a variance that is larger than the mean a phenomenon known as “over dispersion”. We discuss potential applications of the distribution as a model of counts, and under the assumption of independence we will perform statistical inference on the ratio of two means, with generalization to testing the homogeneity of several means. Methods: Bayesian methods depend on the choice of the prior distributions of the population parameters. In this paper, we describe a Bayesian approach for estimation and inference on the parameters of several independent Inflated Poisson (IPD) distributions with two possible priors, the first is the reciprocal of the square root of the Poisson parameter and the other is a conjugate Gamma prior. The parameters of Gamma distribution are estimated in the empirical Bayesian framework using the maximum likelihood (ML) solution using nonlinear mixed model (NLMIXED) in SAS. With these priors we construct the highest posterior confidence intervals on the ratio of two IPD parameters and test the homogeneity of several populations. Results: We encountered convergence problem in estimating the hyperparameters of the posterior distribution using the NLMIXED. However, direct maximization of the predictive density produced solutions to the maximum likelihood equations. We apply the methodologies to RNA-SEQ read count data of gene expression values. 展开更多
关键词 Distributions of Over-Dispersed counts Lagrange Class of Distributions Knowledge Transfer Gamma Prior Posterior Inference Wilson-Hilferty Transformation RNA_SEQ Read counts Data
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Bird Habitats in Urban Environments: A Case from an Urban Landfill in and around Tayba Al Hasanab Landfill, Khartoum, Sudan
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作者 Mutasim Essa Abdallah Adam Mawya Ahmed Elshafea Mohamed 《Journal of Environmental Protection》 2024年第8期887-905,共19页
Managed open landfill sites can serve as crucial feeding grounds for birds. Studies have demonstrated that garbage dumps offer favorable feeding habitats for various trophic generalist species, including storks and sc... Managed open landfill sites can serve as crucial feeding grounds for birds. Studies have demonstrated that garbage dumps offer favorable feeding habitats for various trophic generalist species, including storks and scavenger raptors. This study aimed to assess bird diversity and abundance in and around Tayba Al Hasanab Landfill, Khartoum. A bird census was conducted using block counts in January 2021. A questionnaire complemented field observations, and interviews were conducted with landfill authorities and waste collectors to gather information on bird availability, numbers, and diversity. During the block counts, 23 bird species were recorded inside and around the landfill. These species directly relied on food resources available at and around the landfill, belonging to 8 orders and 11 families. The four most abundant species foraging at the landfill were Sparrow House (Passer domesticus) with 97 individuals, Black kite (Milvus migrans) with 67 individuals, cattle egret (Bubulcus ibis) with 42 individuals, and Laughing Dove (Spilopelia senegalensis) with 36 individuals. This suggests that these species are the primary exploiters of food resources at the landfill. The results indicate that all species are considered least concerned except the Egyptian Vulture (Neophron percnopterus), which is classified as endangered. Most of the interviewed individuals reported seeing birds in the study area. The study recorded instances of dead birds, such as a white stork colliding and being electrocuted with a transition line observed at different sites along transmission lines near the landfill. Surveys around Tayba landfill need to be conducted to identify deadly power lines for replacement or implement possible mitigation measures on power lines running parallel and close to the Tayba landfills. The avian community foraging at the landfill displayed fluctuations in abundance and interspecific interactions across seasons. Given that the substantial influx of birds to landfills can pose various environmental challenges in 展开更多
关键词 Bird Diversity Block counts Endangered Species COLLISIONS Electrocutions Landfill Management
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三维加速度counts估算不同步速能量消耗应用初探 被引量:6
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作者 管培培 丁宁炜 +1 位作者 汤强 刘春辉 《山东体育科技》 北大核心 2013年第1期72-75,共4页
以间接热测定法为标准,探索counts与能量消耗之间的关系,建立基于三维加速度counts能耗推算方程,寻求不同强度身体运动的counts切点。实验选取115名受试者,佩戴Cortex-3B便携式气体代谢分析仪与ActiGraph GT3X三轴加速度计,分别采用4.8k... 以间接热测定法为标准,探索counts与能量消耗之间的关系,建立基于三维加速度counts能耗推算方程,寻求不同强度身体运动的counts切点。实验选取115名受试者,佩戴Cortex-3B便携式气体代谢分析仪与ActiGraph GT3X三轴加速度计,分别采用4.8km/h、5.6km/h、6.4km/h、7.2km/h、8.0km/h、8.8km/h步速。结果认为:不同步速下合矢量counts性别间差异不显著;不同步速下体重组别合矢量counts差异无统计学意义;身高、去脂体重与VO2、MET相关性较低,而性别、BMI都在0.2左右水平上显著相关;将BMI与性别引入推算方程,有效提高了counts预测能耗的准确性。 展开更多
关键词 三轴加速度计 counts 能量消耗 合矢量 校准
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Standard manual capsulorhexis / Ultrasound phacoemulsification compared to femtosecond laser-assisted capsulorhexis and lens fragmentation in clear cornea small incision cataract surgery 被引量:7
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作者 Anastasios John Kanellopoulos George Asimellis 《Eye and Vision》 SCIE 2016年第1期154-165,共12页
Background:Femtosecond-laser assisted clear cornea cataract surgery may hold promise in safer and more effective procedures.We decided to perform a comparative study to standard manual incision phacoemulsification sur... Background:Femtosecond-laser assisted clear cornea cataract surgery may hold promise in safer and more effective procedures.We decided to perform a comparative study to standard manual incision phacoemulsification surgery.Methods:This is a single-center,single-intervention,and prospective comparative data evaluation of 133 consecutive cases subjected to cataract surgery.Group-A(Phaco),manual capsulorhexis&ultrasound phacoemulsification(n=66);Group-B femtosecond-laser assisted capsulorhexis and lens fragmentation(n=67),employing the LenSx laser(Alcon Surgical,Ft.Worth,TX).All cases were evaluated for refraction,visual acuity,keratometry,tomography,pachymetry,endothelial cell counts,intraocular pressure,and type of intraocular lens(IOL)implanted.The groups were matched for age,gender,pre-operative vision metrics,and cataract grade,and were followed up to 1 year.Results:In group-A post-operative uncorrected distance visual acuity(UDVA)was 20/20 or better in 61.5%and 20/25 or better in 78.5%of the eyes.The femtosecond laser group-B had improved outcomes(p=0.075 and p=0.042,respectively):post-operative UDVA was 20/20 or better in 62.7%of the eyes and 20/25 or better in 85.1%.Linear regression scatterplots of achieved versus attempted spherical equivalent had excellent regression coefficients(r^(2)=0.983 in group-A and 0.979 in group-B).There were 75.2%cases in group-A and 80.6%in group-B(p=0.8732)within±0.50 D of targeted refractive equivalent.Slight trend of under-correction was noted in group-A.Average residual manifest cylinder in the toric subgroup-A was-0.50 D(95%Limit-of-Agreement(LoA)=-0.78 D),and in toric subgroup-B-0.45 D(LoA=-0.45 D).Conclusions:Mean spherical equivalent refraction and visual acuity are comparable with laser cataract surgery compared with manual capsulorhexis&ultrasound phacoemulsification.Improved astigmatism correction may be among the benefits of femtosecond laser–assisted cataract surgery.Transient corneal edema may be a first day transient disadvantage in femtosecond laser–assisted 展开更多
关键词 Femto-second laser cataract surgery Manual capsulorhexis LenSx Toric IOL PHACOEMULSIFICATION Refractive outcomes Endothelial cell counts Corneal edema Clear cornea small-incision cataract surgery
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Blood cell counts and nonalcoholic fatty liver disease: Evidence from Mendelian randomization analysis
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作者 Bin Hu Ai-Hong Wan +7 位作者 Xi-Qiao Xiang Yuan-Hao Wei Yi Chen Zhen Tang Chang-De Xu Zi-Wei Zheng Shao-Ling Yang Kun Zhao 《World Journal of Hepatology》 2024年第8期1145-1155,共11页
BACKGROUND Previous research has highlighted correlations between blood cell counts and chronic liver disease.Nonetheless,the causal relationships remain unknown.AIM To evaluate the causal effect of blood cell traits ... BACKGROUND Previous research has highlighted correlations between blood cell counts and chronic liver disease.Nonetheless,the causal relationships remain unknown.AIM To evaluate the causal effect of blood cell traits on liver enzymes and nonalcoholic fatty liver disease(NAFLD)risk.METHODS Independent genetic variants strongly associated with blood cell traits were extracted from a genome-wide association study(GWAS)conducted by the Blood Cell Consortium.Summary-level data for liver enzymes were obtained from the United Kingdom Biobank.NAFLD data were obtained from a GWAS meta-analysis(8434 cases and 770180 controls,discovery dataset)and the Fingen GWAS(2275 cases and 372727 controls,replication dataset).This analysis was conducted using the inverse-variance weighted method,followed by various sensitivity analyses.RESULTS One SD increase in the genetically predicted haemoglobin concentration(HGB)was associated with aβof 0.0078(95%CI:0.0059-0.0096),0.0108(95%CI:0.0080-0.0136),0.0361(95%CI:0.0156-0.0567),and 0.0083(95%CI:00046-0.0121)for alkaline phosphatase(ALP),alanine aminotransferase(ALT),aspartate aminotransferase,and gammaglutamyl transferase,respectively.Genetically predicted haematocrit was associated with ALP(β=0.0078,95%CI:0.0052-0.0104)and ALT(β=0.0057,95%CI:0.0039-0.0075).Genetically determined HGB and the reticulocyte fraction of red blood cells increased the risk of NAFLD[odds ratio(OR)=1.199,95%CI:1.087-1.322]and(OR=1.157,95%CI:1.071-1.250).The results of the sensitivity analyses remained significant.CONCLUSION Novel causal blood cell traits related to liver enzymes and NAFLD development were revealed through Mendelian randomization analysis,which may facilitate the diagnosis and prevention of NAFLD. 展开更多
关键词 Blood cell counts Liver enzymes Nonalcoholic fatty liver disease Genome-wide association Mendelian randomization study Causal relationship
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