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Sysmex UF5000尿沉渣分析仪建立RBC WBC CAST阳性cut off值及准确性评估 被引量:2
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作者 邱慧娜 陈雅斌 +1 位作者 周静琪 张志珊 《基层医学论坛》 2021年第5期670-672,共3页
目的建立Sysmex UF5000尿沉渣分析仪检测尿液标本相关参数红细胞(RBC)、白细胞(WBC)、管型(CAST)的阳性cut off值,并评价其性能。方法选取1059例尿液标本在Sysmex UF5000尿沉渣分析仪上进行检测,并离心镜检。以镜检结果作为金标准,ROC... 目的建立Sysmex UF5000尿沉渣分析仪检测尿液标本相关参数红细胞(RBC)、白细胞(WBC)、管型(CAST)的阳性cut off值,并评价其性能。方法选取1059例尿液标本在Sysmex UF5000尿沉渣分析仪上进行检测,并离心镜检。以镜检结果作为金标准,ROC曲线分析RBC、WBC、CAST的阳性cut off值,并计算其敏感性、特异性、符合率、假阳性率和假阴性率等。进一步分析假阳性标本的影响因素和部分假阴性标本。结果阳性cut off值:RBC>16/μL(男)或>15/μL(女);WBC>17/μL(男)或>30/μL(女);CAST>0.49/μL。相关的敏感性、特异性、符合率均较高。假阳性标本影响因素中RBC男性主要是结晶,女性以结晶、细菌为主;WBC女性以鳞状上皮细胞为主,男性未见明显的影响因素;CAST均以黏液丝和鳞状上皮细胞为主。假阴性率低于5%,其中仅有9例为肾脏、泌尿系统疾病标本,占比0.85%。结论本实验室设置的UF5000尿沉渣分析仪RBC、WBC、BACT阳性cut off值,相关的敏感性、特异性、假阴性率和符合率均符合ISO15189认可和实验室的日常工作需求。 展开更多
关键词 Sysmex UF5000尿沉渣分析仪 RBC WBC CAST阳性 cut off 评估
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血清过敏原特异性IgE酶联免疫吸附法检测CUT OFF值的建立 被引量:4
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作者 滕凤猛 贾宁人 《国际检验医学杂志》 CAS 2022年第12期1521-1524,共4页
目的通过对酶联免疫吸附法检测血清中过敏原特异性IgE的干扰因素分析和判读方式优化,建立该实验室的CUT OFF值。方法采用酶联免疫吸附法过敏原特异性IgE检测试剂盒,对861例患者血清中过敏原特异性IgE进行定性检测;采用专用扫描分析软件... 目的通过对酶联免疫吸附法检测血清中过敏原特异性IgE的干扰因素分析和判读方式优化,建立该实验室的CUT OFF值。方法采用酶联免疫吸附法过敏原特异性IgE检测试剂盒,对861例患者血清中过敏原特异性IgE进行定性检测;采用专用扫描分析软件判读结果并结合人工辅助判读,依据统计学方法建立该实验室的CUT OFF值。根据不同的判读方式结合试剂说明书提供的CUT OFF值,分别计算不同CUT OFF值条件下的假阴性率和假阳性率;比较两者之间有无差异。结果分析软件判读结果显示,蛋清、屋尘螨、屋尘和柏树的血清过敏原特异性IgE判读的CUT OFF值为0.29 IU/mL,各组之间差异无统计学意义(P>0.05)。鳕鱼、虾、牛肉、芒果、花生、苦艾和猫毛血清过敏原特异性IgE判读的CUT OFF值为0.21 IU/mL,各组之间差异无统计学意义(P>0.05)。牛奶和点青霉血清过敏原特异性IgE判读的CUT OFF值为0.25 IU/mL,各组之间差异无统计学意义(P>0.05)。结合人工辅助判读结果显示,屋尘螨、屋尘、苦艾和点青霉血清过敏原特异性IgE判读的CUT OFF值为0.27 IU/mL,各组之间差异无统计学意义(P>0.05)。鳕鱼、虾、牛肉、芒果、花生和猫毛血清过敏原特异性IgE判读的CUT OFF值为0.21 IU/mL,各组差异无统计学意义(P>0.05)。牛奶和蛋清血清过敏原特异性IgE判读的CUT OFF值为0.19 IU/mL,差异无统计学意义(P>0.05)。柏树血清过敏原特异性IgE抗体判读的CUT OFF值为0.33 IU/mL。结论各实验室应建立各自的血清过敏原特异性IgE CUT OFF值。采用人工辅助判读方式可以排除干扰因素,降低假阳性率和假阴性率,为临床提供准确可靠的结果。 展开更多
关键词 血清 过敏原 特异性IGE 酶联免疫吸附法 cut off
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Squeezing Effects on the Estimation Precision of Cut off Frequency
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作者 Asghar Ullah Khalid Khan 《Journal of Quantum Information Science》 2021年第1期13-23,共11页
We study the behavior of quantum Fisher information for a qubit probe that is interacting with a squeezed thermal environment. We analyzed the effect of squeezing parameters on the dynamics of quantum Fisher informati... We study the behavior of quantum Fisher information for a qubit probe that is interacting with a squeezed thermal environment. We analyzed the effect of squeezing parameters on the dynamics of quantum Fisher information which affects the optimal precision of the estimation parameter. We show that the squeezed field may offer a significant role in the precise measurement of the parameter cut-off frequency which is linked to the environment correlation time. Our results may be useful in quantum metrology, communication, and quantum estimation processes. 展开更多
关键词 Quantum Fisher information (QFI) Squeezed Thermal Environment Qubit Probe cut off Frequency
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Hongjiadu and Yinzidu hydropower stations on Wujiang River were successfully cut off
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《Electricity》 2001年第4期7-7,共1页
关键词 Hongjiadu and Yinzidu hydropower stations on Wujiang River were successfully cut off
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Cut Off质控图的意义及应用的探讨
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作者 李昱君 《检验医学与临床》 CAS 2013年第A02期277-278,共2页
提高检测准确度和灵敏度,一直是检验的追求,也一直是困扰检验的难题,它一方面依赖工作人员素质的提高;一方面依赖检测方法、技术和设备的进步。如何将阴阳性(或反应性)更准确地区分出来,很大程度上取决于检测方法与技术的进步,... 提高检测准确度和灵敏度,一直是检验的追求,也一直是困扰检验的难题,它一方面依赖工作人员素质的提高;一方面依赖检测方法、技术和设备的进步。如何将阴阳性(或反应性)更准确地区分出来,很大程度上取决于检测方法与技术的进步,其中科学的CutOff是不可忽视的:当前ELISA比较科学实用的CutOff产生原理有2种:1.测定阴阳性标本,在NCutOff和PCutOff的基础上根据灰区的大小,结合假阴阳性确定CutOff;2.加测转化型血清,将能区别转化型样本的OD作为CutOff。 展开更多
关键词 cut off 质量控制图 室内质控 误差来源分析
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Analytical-Numerical Model for the Cut off Frequency of AIGaNIGaN High Electron Mobility Transistors
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作者 Rajab Yahyazadeh Zahra Hashempour 《材料科学与工程(中英文B版)》 2011年第2期190-199,共10页
关键词 高电子迁移率晶体管 数值模型 频率分析 数值分析模型 电压特性 截止频率 泊松方程 电子陷阱
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An analytical model for the cut off frequency and noise of AIGaN/GaN high electron mobility transistor (HEMTs)
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作者 Rajab Yahyazadeh Zahra Hashempour +1 位作者 Manouchehr Kalafi Mohammad Reza Aboulhasani 《材料科学与工程(中英文版)》 2009年第12期22-25,共4页
关键词 HEMT器件 高电子迁移率晶体管 计算模型 截止频率 噪声分析 GaN 界面陷阱密度 氮化镓
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ONECUT2高表达介导胃癌复发患者5-FU化疗耐药
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作者 朱海峰 陈述 +1 位作者 龙卫国 王旭 《江苏大学学报(医学版)》 CAS 2024年第1期19-24,共6页
目的:探究One cut结构域家族成员2(ONECUT2)是否可以作为对5-FU耐药的胃癌复发患者的治疗靶点。方法:利用癌症基因组图谱(TCGA)数据库分析ONECUT2基因在胃癌患者及胃癌复发患者的表达情况。利用基因集富集分析(GSEA)评估TCGA数据库中ONE... 目的:探究One cut结构域家族成员2(ONECUT2)是否可以作为对5-FU耐药的胃癌复发患者的治疗靶点。方法:利用癌症基因组图谱(TCGA)数据库分析ONECUT2基因在胃癌患者及胃癌复发患者的表达情况。利用基因集富集分析(GSEA)评估TCGA数据库中ONECUT2表达量与药物代谢相关生物学过程的相关性。利用CCK-8细胞毒性实验评估胃癌细胞敲低或过表达ONECUT2对5-FU的耐药情况。分析30例胃癌术后复发患者ONECUT2表达量与5-FU治疗效果的相关性。结果:TCGA数据库分析显示,在经受过化疗且复发的胃癌患者中,ONECUT2高表达的患者无病间隔期(disease-free interval,DFI)更短。GSEA分析结果表明,ONECUT2高表达与异生药物代谢通路呈正相关,这提示可能与胃癌患者的耐药相关。体外实验中,敲低ONECUT2降低胃癌细胞对5-FU的半数抑制浓度(IC_(50))值;反之,过表达ONECUT2增加细胞对5-FU的IC_(50)值。30例胃癌复发患者对5-FU的药物敏感性与ONECUT2表达量相关。结论:胃癌复发患者的ONECUT2表达量更高,ONECUT2高表达与胃癌复发患者的5-FU耐药相关,可能是潜在的治疗靶点。 展开更多
关键词 One cut结构域家族成员2 胃癌复发 5-FU耐药 GSEA 细胞毒性 半数抑制浓度
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Instability mechanism of mining roadway passing through fault at different angles in kilometre-deep mine and control measures of roof cutting and NPR cables 被引量:2
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作者 SUN Xiaoming WANG Jian +6 位作者 ZHAO Wenchao MING Jiang ZHANG Yong LI Zhihu MIAO Chengyu GUO Zhibiao HE Manchao 《Journal of Mountain Science》 SCIE CSCD 2024年第1期236-251,共16页
The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and ... The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and field experiments in the context of the Daqiang coal mine located in Shenyang, China. The stability control countermeasure of "pre-splitting cutting roof + NPR anchor cable"(PSCR-NPR) is simultaneously proposed. According to the different deformation characteristics of the roadway, the faults are innovatively classified into three types, with α of type I being 0°-30°, α of type II being 30°-60°, and α of type III being 60°-90°. The full-cycle stress evolution paths during mining roadway traverses across different types of faults are investigated by numerical simulation. Different pinch angles α lead to high stress concentration areas at different locations in the surrounding rock. The non-uniform stress field formed in the shallow surrounding rock is an important reason for the instability of the roadway. The pre-cracked cut top shifted the high stress region to the deep rock mass and formed a low stress region in the shallow rock mass. The high prestressing NPR anchor cable transforms the non-uniform stress field of the shallow surrounding rock into a uniform stress field. PSCR-NPR is applied in the fault-through roadway of Daqiang mine. The low stress area of the surrounding rock was enlarged by 3-7 times, and the cumulative convergence was reduced by 45%-50%. It provides a reference for the stability control of the deep fault-through mining roadway. 展开更多
关键词 Kilometre-deep mine Fault Mining roadway Failure mechanism Pre-splitting cutting roof High pre-stress NPR anchor cable
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Lipoprotein (a) Cut-Off in Chronic Kidney Disease Patients with a History of Cardiovascular Disease in Center Hospital University Souro SANOU, Burkina Faso
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作者 Ollo Da Aoua Semde +7 位作者 Arnaud Kouraogo Emmanuel Zongo Amidou Sawadogo Aristide Zongo Fatou Gueye Tall Souleymane Fofana Sanata Bamba Georges Anicet Ouedraogo 《Advances in Biological Chemistry》 2023年第6期228-235,共8页
Patients living with chronic kidney disease (CKD) are at high risk of cardiovascular events. Our aim in this study was to assess the cut-off value for lipoprotein (a) (Lp(a)) in CKD patients with a history of cardiova... Patients living with chronic kidney disease (CKD) are at high risk of cardiovascular events. Our aim in this study was to assess the cut-off value for lipoprotein (a) (Lp(a)) in CKD patients with a history of cardiovascular disease (CVD). This was a cross-sectional study. Variables including age, sex, history of CVD, body mass index and CKD stage, were collected during CKD patient’s first admission in the nephrology dialysis department. Blood samples were collected for quantitative determination of Lp(a) by immunoturbidimetric method. They were divided into two groups: CKD patients without history of CVD and CKD patients with history of CVD. Fisher’s exact test was used to assess associations with a significance level of 0.05%. Area under the curve (AUC) and new cut-off value for Lp(a) were identified by drawing Receiver Operating Characteristic (ROC) curve. A total of seventy CKD patients with median age of 43 years [minimum-maximum = 15 - 78 years] were included. Patients with history of CVD were 65.71% (46/70). New Lp(a) cut-off point in CKD patients with history of CVD was 66.50 nmol/L [sensitivity, 87.00%;specificity, 58.30%;AUC = 0.727;p = 0.000]. ROC curve demonstrated good performance of Lp(a) to screen CKD patients with history of CVD. Further research is needed to determine an LPA gene polymorphism’s contribution to increasing risk for CVD at each kidney disease stage. 展开更多
关键词 Lipoprotein (a) cut-off Chronic Kidney Disease Cardiovascular Disease
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Unraveling engineering disturbance effects on deformation in red-bed mudstone railway cuttings:incorporating crack-facilitated moisture diffusion
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作者 HUANG Kang DAI Zhangjun +3 位作者 YAN Chengzeng YAO Junkai CHI Zecheng CHEN Shanxiong 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1663-1682,共20页
Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in expansion, deformation, and cracking upon exposure to moisture. This study addresses upli... Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in expansion, deformation, and cracking upon exposure to moisture. This study addresses uplift deformation disasters in high-speed railways by employing a moisture diffusion-deformation-fracture coupling model based on the finite-discrete element method(FDEM). The model integrates the influence of cracks on moisture diffusion. The investigation into various excavation depths reveals a direct correlation between depth and the formation of tensile cracks at the bottom of the railway cutting. These cracks expedite moisture migration, significantly impacting the temporal and spatial evolution of the moisture field. Additionally, crack expansion dominates hygroscopic deformation, with the lateral coordinate of the crack zone determining peak vertical displacement. Furthermore, key factors influencing deformation in railway cuttings, including the swelling factor and initial moisture content at the bottom of the cutting, are explored. The number of tensile and shear cracks increases with greater excavation depth, particularly concerning shear cracks. Higher swelling factors and initial moisture contents result in an increased total number of cracks, predominantly shear cracks. Numerical calculations provide valuable insights, offering a scientific foundation and directional guidance for the precise prevention, control, prediction, and comprehensive treatment of mudstone-related issues in high-speed railways. 展开更多
关键词 Red-bed mudstone Railway cutting FDEM Moisture diffusion DEFORMATION CRACK
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Precipitates Generation Mechanism and Surface Quality Improvement for Aluminum Alloy 6061 in Diamond Cutting
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作者 王海龙 DENG Wenping 王素娟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期150-159,共10页
To improve the surface quality for aluminum alloy 6061(Al6061) in ultra-precision machining, we investigated the factors affecting the surface finish in single point diamond turning(SPDT)by studying influence of the p... To improve the surface quality for aluminum alloy 6061(Al6061) in ultra-precision machining, we investigated the factors affecting the surface finish in single point diamond turning(SPDT)by studying influence of the precipitates generation of Al6061 on surface integrity and surface roughness.Based on the Johnson-Mehl-Avrami solid phase transformation kinetics equation, theoretical and experimental studies were conducted to build the relationship between the aging condition and the type, size and number of the precipitates for Al6061. Diamond cutting experiments were conducted to machine Al6061 samples under different aging conditions. The experimental results show that, the protruding on the chip surface is mainly Mg_(2)Si and the scratches on the machined surface mostly come from the iron-containing phase(α-, β-AlFeSi).Moreover, the generated Mg_(2)Si and α-, β-AlFeSi affect the surface integrity and the diamond turned surface roughness. Especially, the achieved surface roughness in SPDT is consistent with the variation of the number of AlFeSi and Mg_(2)Si with the medium size(more than 1 μm and less than 2 μm) in Al6061. 展开更多
关键词 Al6061 PRECIPITATES aging treatment diamond cutting surface roughness
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Endoscopic radial incision and cutting method for adult congenital duodenal webs:A case report
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作者 Hyun Deok Shin 《World Journal of Clinical Cases》 SCIE 2024年第18期3622-3628,共7页
BACKGROUND Congenital duodenal webs are rare in adults and can lead to various symptoms such as nausea,vomiting,and postprandial fullness.The treatment for this disease is mostly surgical.Endoscopic treatment techniqu... BACKGROUND Congenital duodenal webs are rare in adults and can lead to various symptoms such as nausea,vomiting,and postprandial fullness.The treatment for this disease is mostly surgical.Endoscopic treatment techniques have been developed and attempted for this disease.Endoscopic radial incision and cutting(RIC)techniques are reportedly very effective in benign anastomotic stricture.This case report highlights the effectiveness and safety of endoscopic RIC as a minimally invasive treatment for adult congenital duodenal webs.CASE SUMMARY A 23-year-old female patient with indigestion was referred to a tertiary hospital.The patient complained of postprandial fullness in the epigastric region.Previous physical examinations or blood tests indicated no abnormalities.Computed tomography revealed an eccentric broad-based delayed-enhancing mass-like lesion in the second portion of the duodenum.Endoscopy showed an enlarged gastric cavity and a significantly dilated duodenal bulb;a very small hole was observed in the distal part of the second portion,and scope passage was not possible.Gastrografin upper gastrointestinal series was performed,revealing an intraduodenal barium contrast-filled sac with a curvilinear narrow radiolucent rim,a typical"windsock"sign.Endoscopic RIC was performed on the duodenal web.The patient recovered uneventfully.Follow-up endoscopy showed a patent duodenal lumen without any residual stenosis.The patient reported complete resolution of symptoms at the 18-month follow-up.CONCLUSION Endoscopic RIC may be an effective treatment for congenital duodenal webs in adults. 展开更多
关键词 Congenital duodenal web Endoscopic treatment Radial incision and cutting method Surgery Case report
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Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery
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作者 Xi-Dao Wu Peng Xiao +2 位作者 Bei Liu Guang-Jin Chen Jian-Hua Pang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期974-986,共13页
CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility reduction.However,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fractio... CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility reduction.However,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely researched.In this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil recovery.Firstly,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT cell.Subsequently,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary tube.Furthermore,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were analyzed.The results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) emulsion.An inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was confirmed.CO_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water cut.Eventually,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,respectively.This work may provide guidelines for EOR using CO_(2) emulsions with high water cut. 展开更多
关键词 CO_(2)/H_(2)O emulsion High water cut CO_(2) mobility control Enhanced oil recovery
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Cutting Propagation Technique of Pennisetum purpureum Schum
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作者 Yuanbin HU Jing ZHANG +2 位作者 Yanan LIU Xiaoyu LIANG Yang JI 《Plant Diseases and Pests》 2024年第2期27-31,共5页
[Objectives]The paper was to study the cutting propagation technique of Pennisetum purpureum Schum and to provide a technical reference for establishing an efficient cutting propagation method.[Methods]Six treatments ... [Objectives]The paper was to study the cutting propagation technique of Pennisetum purpureum Schum and to provide a technical reference for establishing an efficient cutting propagation method.[Methods]Six treatments were set up using P.purpureum cv.Guiminyin and P.purpureum cv.Guimu-1 as test materials,including 1-node oblique insertion,1-node oblique insertion+rooting powder,1-node transverse burial,2-node oblique insertion,2-node oblique insertion+rooting powder and 2-node transverse burial.The following indices were observed and determined for P.purpureum cuttings:emergence rate,rooting rate,root number,longest root length,fresh root weight,plant height,number of tillers,number of leaves,and fresh stem and leaf weight.[Results]In the 2-node cutting+rooting powder treatment,Guiminyin and Guimu-1 exhibited the highest survival rate,root growth indices,and stem and leaf growth indices,with the emergence rates of 94.29%and 90.26%,respectively.The 2-node cutting treatment followed closely behind,while the 1-node cutting treatment had the lowest indices.Under the same treatment,Guimuyin exhibited higher mean values for plant height,number of leaves,fresh stem and leaf weight,longest root length,and fresh root weight compared to Guimu-1.However,it had lower mean number of tillers,and emergence rate and rooting rate of the 1-node cutting treatment compared to Guimu-1.[Conclusions]The P.purpureum cuttings thrived in the 2-node cutting+rooting powder treatment,and the overall cutting effect of Guiminyin was superior to that of Guimu-1. 展开更多
关键词 Pennisetum purpureum Schum cutTING PROPAGATION Emergence rate
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Cutting-edge Technological Innovation Outcome Displayed at 2024 Beijing Science and Technology Week
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作者 Zhang Yida 《China's Foreign Trade》 2024年第3期47-49,共3页
The 2024 National Science and Technology Week and Beijing Science and Technology Week opened in Shougang Park in Shijingshan District from May 25 to June 1.Under the theme of“Carrying forward the spirit of scientists... The 2024 National Science and Technology Week and Beijing Science and Technology Week opened in Shougang Park in Shijingshan District from May 25 to June 1.Under the theme of“Carrying forward the spirit of scientists and inspiring societal innovation,”this event focused on the new-generation IT technology,medical health,energy and technology,modern agriculture and intelligent manufacturing industries. 展开更多
关键词 DISTRICT cutTING opened
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Research on the Resistance of Cutting Mechanism of Mining Longitudinal Roadheader
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作者 Mengjiao NIU Yong ZHAO Yongliang YUAN 《Mechanical Engineering Science》 2024年第1期8-12,共5页
In order to accurately obtain the dynamic characteristics of the cutting mechanism of the mining longitudinal roadheader,combined with the working principle of the mining longitudinal roadheader,the theoretical analys... In order to accurately obtain the dynamic characteristics of the cutting mechanism of the mining longitudinal roadheader,combined with the working principle of the mining longitudinal roadheader,the theoretical analysis and derivation are carried out in detail.By using ADAMS to simulate,the resistance curve and torque curve of the cutting mechanism in different directions are obtained.The results show that ADAMS can effectively predict the excavation resistance and torque of the cutting mechanism of mining longitudinal roadheader,which has certain reference value for future optimization design. 展开更多
关键词 longitudinal roadheader cutting mechanism dynamic characteristics DYNAMICS
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Design and Numerical Simulation of Dust Removal System for Sutomotive Iongitudinal Beam Plasma Cutting
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作者 Wenqiang GAO Xudong MA Heyu TIAN 《Mechanical Engineering Science》 2024年第1期30-34,共5页
To improve the poor efficiency of the dust removal system in the plasma cutting station of automotive longitudinal beams,and reduce the cutting surface quality degradation due to dust,a bottom-side suction dust remova... To improve the poor efficiency of the dust removal system in the plasma cutting station of automotive longitudinal beams,and reduce the cutting surface quality degradation due to dust,a bottom-side suction dust removal system is designed,and the dust removal effect is optimized through the setting of the following dampers and diversion plates.The result of numerical simulation indicates that the particle collection rate can reach 99.44%,and the field test also proves the effectiveness of the dust removal system,which is of guiding significance for the transformation of other similar dust removal systems. 展开更多
关键词 plasma cutting dust removal equipment SIMULATION
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基于cut-off方法刚性承台下群桩基础优化分析 被引量:2
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作者 梁发云 陈海兵 《岩土力学》 EI CAS CSCD 北大核心 2011年第S1期61-65,共5页
针对刚性筏板下群桩基础优化设计问题进行分析,通过改变桩长分布来调整各桩的荷载分担,群桩分析采用基于弹性理论的积分方程方法,并通过cut-off方法来反映桩的弹塑性特性,实现群桩基础的弹塑性优化分析,改进了常规弹性分析方法的缺陷。... 针对刚性筏板下群桩基础优化设计问题进行分析,通过改变桩长分布来调整各桩的荷载分担,群桩分析采用基于弹性理论的积分方程方法,并通过cut-off方法来反映桩的弹塑性特性,实现群桩基础的弹塑性优化分析,改进了常规弹性分析方法的缺陷。算例分析表明,随着外荷载的不断增加,角桩首先达到极限荷载,对角桩超出极限荷载的部分进行重新分布,继而使得边桩逐渐达到极限承载状态,继续加载直至内桩也达到极限承载状态,从而引起桩筏基础的整体破坏。采用cut-off方法可以改进基础变刚度优化设计,使之与实际情况更为吻合。 展开更多
关键词 cut-off方法 长短桩 优化分析 刚性承台 弹塑性
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利用RIBA试验确定HCV抗体检测的cut-off值及比较分析 被引量:1
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作者 陈陆 徐东 +4 位作者 宋玉杰 石磊 李英 曹正 翟燕红 《标记免疫分析与临床》 CAS 2022年第9期1465-1468,共4页
目的利用重组蛋白免疫印迹分析(RIBA)实验,制定本实验室所用的日本希森美康公司的HISCL-5000型化学发光免疫分析仪及配套的相关试剂检测丙型肝炎病毒抗体(抗-HCV)的cut-off值。方法在2015年10月至2016年9月所检测的19341例患者标本中收... 目的利用重组蛋白免疫印迹分析(RIBA)实验,制定本实验室所用的日本希森美康公司的HISCL-5000型化学发光免疫分析仪及配套的相关试剂检测丙型肝炎病毒抗体(抗-HCV)的cut-off值。方法在2015年10月至2016年9月所检测的19341例患者标本中收集抗-HCV阳性标本80例,进行RIBA确认实验后进行分析,再利用ROC曲线计算出cut-off值。结果在本室HCV抗体阳性率为0.41%的数据中,RIBA结果可分为3种,其中25例(31.3%)为阴性,18例(22.5%)为不确定,37例(46.2%)为阳性。当截断值为3.95 COI时,灵敏度为81.1%,特异性为95.1%。另外当特异性为100%时,截断值为5.25 COI,灵敏度为73%。结论希森美康HISCL-5000型化学发光免疫分析仪及配套的相关试剂检测丙型肝炎病毒抗体(抗-HCV)与RIBA结果间呈正相关;当cut-off值为3.95 COI时,是一个适合本实验室的cut-off值。 展开更多
关键词 HCV抗体检测 希森美康HISCL-5000 RIBA试验 cut-off
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