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基于波形比对TestBench的Verilog在线自动测试系统设计
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作者 黄继业 金清嵩 +1 位作者 李平 刘鑫 《实验室研究与探索》 北大核心 2025年第2期91-94,109,共5页
为解决Verilog编程练习需求大和现有在线测评系统无法较好地支持Verilog在线评测的问题,设计了基于波形比对TestBench的Verilog在线自动测试系统。系统将标准答案源码和学生提交代码分别仿真,得到两种输出波形并转换为txt文本加以比对,... 为解决Verilog编程练习需求大和现有在线测评系统无法较好地支持Verilog在线评测的问题,设计了基于波形比对TestBench的Verilog在线自动测试系统。系统将标准答案源码和学生提交代码分别仿真,得到两种输出波形并转换为txt文本加以比对,根据比对结果在线自动评分。根据代码正确率给出具体分数,并将代码错误信息以文本形式反馈给学生,帮助学生全面评估自身水平并快速定位纠错。该系统已部署至程序设计类实验辅助教学平台,经过教学实践,能有效提升学生的Verilog编程能力,在教学中取得了显著成效。 展开更多
关键词 Verilog在线自动测试 OJ系统 测试基准 波形比对
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Kali Pi—A Miniature Ultra-Portable Penetration Testing Device
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作者 Ahmed Bin Ali 《Journal of Information Security》 2025年第1期101-113,共13页
Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant... Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant on traditional laptops and computers, which, while portable, lack true ultra-portability. This paper explores the potential impact of developing a dedicated, ultra-portable, low-cost device for on-the-go penetration testing. Such a device could replicate the core functionalities of advanced penetration testing tools, including those found in Kali Linux, within a compact form factor that fits easily into a pocket. By offering the convenience and portability akin to a smartphone, this innovative device could redefine the way penetration testers operate, enabling them to carry essential tools wherever they go and ensuring they are always prepared to conduct security assessments efficiently. This approach aims to revolutionize penetration testing by merging high functionality with unparalleled portability. 展开更多
关键词 Penetration testing Portable Device CYBERSECURITY Raspberry Pi
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Research of NOx Sensors Performance Test
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作者 Zhengang Zhang Zhonggang Tang +3 位作者 Wei Gao Li Liu Cong Wang Hourui Sun 《Journal of Materials Science and Chemical Engineering》 2025年第2期23-30,共8页
NOx sensors, as a core component of diesel engine exhaust treatment system, play an important role in exhaust emission control, which can accurately and quickly detect the NOx and O2 concentration. It has become a nec... NOx sensors, as a core component of diesel engine exhaust treatment system, play an important role in exhaust emission control, which can accurately and quickly detect the NOx and O2 concentration. It has become a necessary option for the detection of existing exhaust emission standards. At present, there is limited and scattered information on knowledge and test methods of NOx sensors, the research of NOx sensors has become a challenging research topic at home and abroad. Based on these requirements, the article systematically integrates the knowledge of principle and testing methods. First of all, through introducing functional description of NOx sensors and the basic principle of NOx sensors, the relevant scholars can have an overall understanding of the product and master the operation mode of products. Secondly, the current status of performance test bench and methods of NOx sensors were described, which can contribute to having a clear understanding of the development process. After that, a new structure of NOx sensors test bench was purposed, which contains six major units including standard gas source, gas mixing unit, analyzer measurement unit, sensor measurement unit, data processing and display unit, exhaust gas treatment unit. And the test bench was validated. The experimental results show that the test bench has the advantages of high-repeatability, high reliability and low cost. And it can realize automatic detection of multiple target values, which is worthy further promotion. Thereby, the article can contribute to the development of its technology indirectly. 展开更多
关键词 NOx Sensors FUNCTION Performance test Basic Principle
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Life-Cycle Bearing Capacity for Pre-Stressed T-beams Based on Full-Scale Destructive Test
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作者 Yushan Ye Tao Gao +4 位作者 Liankun Wang Junjie Ma Yingchun Cai Heng Liu Xiaoge Liu 《Structural Durability & Health Monitoring》 EI 2025年第1期145-166,共22页
To investigate the evolution of load-bearing characteristics of pre-stressed beams throughout their service life and to provide a basis for accurately assessing the actual working state of damaged pre-stressed concret... To investigate the evolution of load-bearing characteristics of pre-stressed beams throughout their service life and to provide a basis for accurately assessing the actual working state of damaged pre-stressed concrete T-beams,destructive tests were conducted on full-scale pre-stressed concrete beams.Based on the measurement and ana-lysis of beam deflection,strain,and crack development under various loading levels during the research tests,combined with the verification coefficient indicators specified in the codes,the verification coefficients of bridges at different stages of damage can be examined.The results indicate that the T-beams experience complete,incom-plete linear,and non-linear stages during the destructive test process.In the complete linear elastic stage,both the deflection and bottom strain verification coefficients comply with the specifications,indicating a good structural load-bearing capacity no longer adheres to the code’s requirements.In the non-linear stage,both coefficients exhi-bit a sharp increase,resulting in a further decrease in the structure’s load-bearing capacity.According to the pro-visions of the current code,the beam can be in the incomplete linear stage when both values fall within the code’s specified range.The strain verification coefficient sourced from the compression zone at the bottom of theflange is not recommended for assessing the bridge’s load-bearing capacity. 展开更多
关键词 Pre-stressed T-beams whole process destructive test bearing capacity verification coefficient
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Hypothetical Willingness to Share the Genetic Test Results among the Relatives of Individuals with HBOC: A Study on the Japanese Population
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作者 Ikumi Kataoka Chieko Itaki Tomisato Miura 《Advances in Breast Cancer Research》 2025年第1期16-28,共13页
Objective: Hereditary breast and ovarian cancer syndrome (HBOC) increases the risk of developing breast, ovarian, prostate, and pancreatic cancers. With the insurance coverage for BRCA genetic testing, the number of i... Objective: Hereditary breast and ovarian cancer syndrome (HBOC) increases the risk of developing breast, ovarian, prostate, and pancreatic cancers. With the insurance coverage for BRCA genetic testing, the number of individuals diagnosed with HBOC has increased. To use these test results effectively, cascade genetic testing (CGT) is recommended for at-risk relatives;however, it is not yet widely available. The purpose of this study was to investigate the willingness of the general population to share genetic test results and undergo CGT, as well as to analyze the factors influencing these decisions. Based on these findings, the study aimed to identify the types of support needed to support the sharing of genetic test results and promote the use of CGT. Methods: An online survey was conducted with 500 participants (50 men and women from each of the five generations, ranging from 20 to 69 years). Results: Among the HBOC blood relatives, 51.2% wanted to share the genetic results and 71.9% expressed a willingness to undergo CGT. “Matters to be shared with relatives” and “Helpful for my cancer prevention” were identified as key factors promoting the willingness to share the BRCA genetic test results and undergo CGT. The motivation for “Helpful for my cancer prevention” had a particularly strong influence on the decision to undergo CGT. Conclusion: In the general population, there is an emerging understanding that the genetic information impacts not only the individuals but also their entire families and can be valuable for cancer prevention. To promote the sharing of BRCA genetic test results and CGT uptake, the healthcare providers should offer support tailored to each family’s circumstances and establish cancer prevention measures recommended for HBOC. 展开更多
关键词 Hereditary Breast and Ovarian Cancer Cascade Genetic testing JAPANESE
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Analysis of the Diagnostic Value of Blood Test Indicators for Anemia
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作者 Xueguo Yu 《Journal of Clinical and Nursing Research》 2025年第1期69-74,共6页
Objective: To analyze the effectiveness of blood test indicators in the differential diagnosis of anemia. Methods: Sixty patients diagnosed with anemia (disease group) from June 2021 to June 2024 were selected. Based ... Objective: To analyze the effectiveness of blood test indicators in the differential diagnosis of anemia. Methods: Sixty patients diagnosed with anemia (disease group) from June 2021 to June 2024 were selected. Based on the type of disease, the group was subdivided into iron deficiency anemia (IDA) with 31 cases, hemolytic anemia (HA) with 11 cases, and aplastic anemia (AA) with 18 cases. Based on the severity of the disease, the group was divided into mild anemia (30 cases), moderate anemia (19 cases), and severe anemia (11 cases). Sixty healthy individuals (control group) were also included, and all underwent blood tests. Comparisons were made between the red blood cell (RBC) indicators of the disease group and the control group, the blood test indicators of different types of anemia, and the serum iron levels of varying severity of anemia. Results: Except for red cell distribution width (RDW), the RBC indicators in the disease group were lower than those in the control group (P < 0.05). Comparisons of RBC indicators among different types of anemia showed significant differences (P < 0.05). Serum iron levels varied significantly among different degrees of anemia severity (P < 0.05). Conclusion: Blood tests can detect anemia, distinguish types of anemia, and assess anemia severity, offering high diagnostic value. 展开更多
关键词 Blood test indicators ANEMIA Differential diagnosis
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A new tube chamber system for evaluation of anterior chamber pressure during phacoemulsification tested in porcine eyes
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作者 Fumiaki Higashijima Makoto Hatano +5 位作者 Manami Ohta Tadahiko Ogata Takuya Yoshimoto Atsushige Ashimori Makiko Wakuta Kazuhiro Kimura 《International Journal of Ophthalmology(English edition)》 2025年第1期9-14,共6页
AIM:To measure the optimal anterior chamber pressure(ACP)for safe phacoemulsification using a new tube chamber system with internal pressure measurement function in the porcine eye.METHODS:The 20-gauge and 21-gauge st... AIM:To measure the optimal anterior chamber pressure(ACP)for safe phacoemulsification using a new tube chamber system with internal pressure measurement function in the porcine eye.METHODS:The 20-gauge and 21-gauge straight tips with yellow and orange sleeves,respectively,were covered by a test chamber combined with a pressure sensor for measuring ACP.This was measured for 20s from 10s after starting aspiration in the linear mode using vacuum levels of 200 and 150 mm Hg with a 20-gauge tip,and 300 and 250 mm Hg with a 21-gauge tip.Using a porcine eye,a pressure sensor fixed with a 0.9 mm corneal incision measured ACP.For the posterior capsule contact assay,porcine eyes were treated as described above,and the ultrasonic needle tip was held at the height of the iris and aspirated for 30s in linear mode at a vacuum of 200 and 150 mm Hg for the 20-gauge tip,and 300 and 250 mm Hg for the 21-gauge tip.The bottle height at which the posterior capsule accidentally contacted the ultrasonic tip was recorded,and the estimated ACP was calculated.RESULTS:The internal pressure of the new tube chamber system and ACP from the porcine eye closely matched proportional changes at vacuum levels of 200 and 150 mm Hg with 20-gauge tips.Similarly,proportional changes at vacuum levels of 300 and 250 mm Hg with the 21-gauge tip were nearly equal.The bottle height at which the posterior capsule contacted with the tip and estimated ACP were 57.5±12.6 cm(20.2±7.9 mm Hg)at 200 mm Hg with a 20-gauge tip,35.0±10.0 cm(16.6±6.3 mm Hg)at 150 mm Hg with a 20-gauge tip,47.5±12.6 cm(18.7±8.7 mm Hg)at 300 mm Hg with a 21-gauge tip,and 32.5±5.0 cm(15.7±3.5 mm Hg)at 250 mm Hg with a 21-gauge tip.CONCLUSION:A comprehensive understanding of this chamber system’s characteristics and usage can resolve anterior chamber instability caused by changing preoperative settings on the phaco machine. 展开更多
关键词 test chamber cataract surgery SETTINGS anterior chamber stability
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Large-scale shaking table test on unlined tunnel in fault zone under threedimensional earthquake
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作者 ZHANG Xiaoyu TAO Zhigang +1 位作者 YANG Xiaojie ZHANG Ruixue 《Journal of Mountain Science》 2025年第1期296-311,共16页
A fault is a geological structure characterized by significant displacement of rock masses along a fault plane within the Earth's crust.The Yunnan Tabaiyi Tunnel intersects multiple fault zones,making tunnel const... A fault is a geological structure characterized by significant displacement of rock masses along a fault plane within the Earth's crust.The Yunnan Tabaiyi Tunnel intersects multiple fault zones,making tunnel construction in fault-prone areas particularly vulnerable to the effects of fault activity due to the complexities of the surrounding geological environment.To investigate the dynamic response characteristics of tunnel structures under varying surrounding rock conditions,a three-dimensional large-scale shaking table physical model test was conducted.This study also aimed to explore the damage mechanisms associated with the Tabaiyi Tunnel under seismic loading.The results demonstrate that poor quality surrounding rock enhances the seismic response of the tunnel.This effect is primarily attributed to the distribution characteristics of acceleration,dynamic strain,and dynamic soil pressure.A comparison between unidirectional and multi-directional(including vertical)seismic motions reveals that vertical seismic motion has a more significant impact on specific tunnel locations.Specifically,the maximum tensile stress is observed at the arch shoulder,with values ranging from 60 to 100 k Pa.Moreover,NPR(Non-Prestressed Reinforced)anchor cables exhibit a substantial constant resistance effect under low-amplitude seismic waves.However,when the input earthquake amplitude reaches 0.8g,local sliding occurs at the arch shoulder region of the NPR anchor cable.These findings underscore the importance of focusing on seismic mitigation measures in fault zones and reinforcing critical areas,such as the arch shoulders,in practical engineering applications. 展开更多
关键词 Fault tunnel Shaking table test Dynamic response Three-directional earthquake Damage mechanism
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C-reactive Protein(CRP)and Procalcitonin(PCT)Combined Testing in the Diagnosis of Elderly Patients with Bacterial Pneumonia
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作者 Bingzhi Li 《Journal of Clinical and Nursing Research》 2025年第1期299-304,共6页
Objective:To analyze the diagnostic value of combined testing of C-reactive protein(CRP)and procalcitonin(PCT)in elderly patients with bacterial pneumonia.Methods:This study included 50 elderly patients with bacterial... Objective:To analyze the diagnostic value of combined testing of C-reactive protein(CRP)and procalcitonin(PCT)in elderly patients with bacterial pneumonia.Methods:This study included 50 elderly patients with bacterial pneumonia as the observation group and 50 patients with non-bacterial pneumonia as the control group,recruited from May 2022 to October 2023.Fasting venous blood samples were collected in the morning from all 100 participants.CRP levels were measured using a fully automated biochemical analyzer,while PCT levels were detected using the immunoturbidimetric luminescence method.Results:CRP and PCT levels were significantly higher in bacterial pneumonia patients[(98.25±11.59)mg/L and(3.57±1.35)μg/L,respectively]compared to the control group[(5.55±2.78)mg/L and(0.25±0.12)μg/L,respectively],with significant intergroup differences(P<0.05).Patients with severe bacterial pneumonia exhibited higher serum CRP and PCT levels compared to those with moderate or mild disease(P<0.05).The combined testing of CRP and PCT showed higher sensitivity and specificity than individual tests.In the observation group,CRP and PCT levels significantly decreased after treatment compared to pre-treatment levels.Conclusion:The combination of CRP and PCT testing provides high diagnostic accuracy for bacterial pneumonia in elderly patients.It effectively differentiates bacterial from non-bacterial infections,offering valuable data to guide clinical treatment. 展开更多
关键词 C-reactive protein(CRP) Procalcitonin(PCT) Combined testing Elderly bacterial pneumonia
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Model tests and numerical analysis of emergency treatment of cohesionless soil landslide with quick-setting polyurethane
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作者 ZHANG Zhichao TANG Xuefeng +2 位作者 HUANG Rufa CAI Zhenjie GAO Anhua 《Journal of Mountain Science》 2025年第1期110-121,共12页
Shotcrete is one of the common solutions for shallow sliding.It works by forming a protective layer with high strength and cementing the loose soil particles on the slope surface to prevent shallow sliding.However,the... Shotcrete is one of the common solutions for shallow sliding.It works by forming a protective layer with high strength and cementing the loose soil particles on the slope surface to prevent shallow sliding.However,the solidification time of conventional cement paste is long when shotcrete is used to treat cohesionless soil landslide.The idea of reinforcing slope with polyurethane solidified soil(i.e.,mixture of polyurethane and sand)was proposed.Model tests and finite element analysis were carried out to study the effectiveness of the proposed new method on the emergency treatment of cohesionless soil landslide.Surcharge loading on the crest of the slope was applied step by step until landslide was triggered so as to test and compare the stability and bearing capacity of slope models with different conditions.The simulated slope displacements were relatively close to the measured results,and the simulated slope deformation characteristics were in good agreement with the observed phenomena,which verifies the accuracy of the numerical method.Under the condition of surcharge loading on the crest of the slope,the unreinforced slope slid when the surcharge loading exceeded 30 k Pa,which presented a failure mode of local instability and collapse at the shallow layer of slope top.The reinforced slope remained stable even when the surcharge loading reached 48 k Pa.The displacement of the reinforced slope was reduced by more than 95%.Overall,this study verifies the effectiveness of polyurethane in the emergency treatment of cohesionless soil landslide and should have broad application prospects in the field of geological disasters concerning the safety of people's live. 展开更多
关键词 Cohesionless soil landslide POLYURETHANE Emergency treatment Reinforcement effect Model test Finite element analysis
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LDRA Testbed在动车EBCU软件测试中的应用与研究
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作者 王贤斌 《现代信息科技》 2025年第1期155-160,共6页
动车制动控制系统是高铁安全运行的重要保障。随着动车系统的复杂性和自动化程度的提高,对制动控制系统的软件测试也提出了更高的要求。文章通过将LDRA Testbed软件自动化测试工具应用于动车EBCU软件,详细介绍了静态分析、单元测试及集... 动车制动控制系统是高铁安全运行的重要保障。随着动车系统的复杂性和自动化程度的提高,对制动控制系统的软件测试也提出了更高的要求。文章通过将LDRA Testbed软件自动化测试工具应用于动车EBCU软件,详细介绍了静态分析、单元测试及集成测试的方法和步骤,并结合实际测试结果分析其有效性和重要性。通过全面的测试手段,不仅提高了EBCU软件的可靠性和安全性,还为动车制动控制系统的维护和优化提供了科学依据。 展开更多
关键词 动车 制动控制系统 testBED 静态分析 单元测试 集成测试
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AquiferTest软件在抽水试验中的应用
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作者 张晋磊 王学谦 闫秀英 《技术与市场》 2025年第1期100-102,107,共4页
通过现场原位抽水试验确定的水文地质参数的精度和准确性会直接影响基坑降水工程的准确性和可靠性。结合在某场地进行的潜水非稳定流抽水试验,在数据处理过程中,传统人工配线法效率、精度低,运用AquiferTest软件计算了潜水含水层渗透系... 通过现场原位抽水试验确定的水文地质参数的精度和准确性会直接影响基坑降水工程的准确性和可靠性。结合在某场地进行的潜水非稳定流抽水试验,在数据处理过程中,传统人工配线法效率、精度低,运用AquiferTest软件计算了潜水含水层渗透系数,采用Neuman法、Boulton法、仿泰斯公式法计算,提高计算结果精度,并对计算结果进行分析优化得到最终结果,符合实际水文地质条件。 展开更多
关键词 抽水试验 渗透系数 Aquifertest软件 潜水含水层
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pytest自动测试框架通用搭建方法研究
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作者 邢浩 孙孟宇 石杰 《山西电子技术》 2025年第1期102-105,共4页
Pytest是一种基于python的自动测试框架,可以实现测试代码的自动化执行,应用十分广泛。由于Pytest支持测试代码自动执行、并行执行、测试报告自动生成等多种功能,因此在搭建pytest开发环境时需要安装各种第三方插件和python依赖包,这给p... Pytest是一种基于python的自动测试框架,可以实现测试代码的自动化执行,应用十分广泛。由于Pytest支持测试代码自动执行、并行执行、测试报告自动生成等多种功能,因此在搭建pytest开发环境时需要安装各种第三方插件和python依赖包,这给pytest开发环境的搭建带来了麻烦。为了给pytest使用人员提供便利,对pytest自动测试框架的通用搭建方法进行了研究。首先介绍了pytest自动测试框架的应用领域和特点;然后分别对联网环境和离网环境下pytest的搭建方法进行了介绍;之后分析了不同操作系统下pytest安装方法的通用性;最后对pytest通用安装方法的应用效果进行了说明。 展开更多
关键词 pytest 自动测试框架 通用搭建方法 联网搭建 离网搭建
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Assessment of cerebrovascular reserve impairment using the breath-holding index in patients with leukoaraiosis 被引量:5
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作者 Ying Bian Jin-Chun Wang +6 位作者 Feng Sun Zi-Yi Sun Yu-Jiao Lin Yang Liu Bin Zhao Li Liu Xiao-Guang Luo 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第8期1412-1418,共7页
Many studies have demonstrated that leukoaraiosis is associated with impaired cerebrovascular reserve function. However, the definitive hemodynamic changes that occur in leukoaraiosis are not clear, and there are many... Many studies have demonstrated that leukoaraiosis is associated with impaired cerebrovascular reserve function. However, the definitive hemodynamic changes that occur in leukoaraiosis are not clear, and there are many controversies. This study aimed to investigate hemodynamic changes in symptomatic leukoaraiosis using transcranial Doppler ultrasonography and the breath-holding test in a Chinese Han population, from northern China. A total of 203 patients who were diagnosed with ischemic stroke or clinical chronic progressive ischemic symptoms were enrolled in this study, including 97 males and 106 females, with an age range of 43-93 years. The severity of leukoaraiosis was evaluated according to the Fazekas grading scale, and patients were divided into four groups accordingly. Grade 0 was no leukoaraiosis, and grades I, II, and III were mild, moderate, and severe leukoaraiosis, respectively, with 44, 79, 44, and 36 cases in each group. Transcranial Doppler ultrasonography and the breath-holding test were performed. The mean blood flow velocity of the bilateral middle cerebral artery was measured and the breath-holding index was calculated. The breath holding index was correlated with leukoaraiosis severity and cognitive impairment. Patients with a low breath holding index presented poor performance in the Montreal Cognitive Assessment (MoCA) and executive function tests. That is, the lower the breath holding index, the lower the scores for the MoCA and the higher for the trail-making test Parts A and B. These results indicate that the breath-holding index is a useful parameter for the evaluation of cerebrovascular reserve impairment in patients with leukoaraiosis. In addition, the breath-holding index can reflect cognitive dysfunction, providing a new insight into the pathophysiology of leukoaraiosis. This study was approved by the Ethics Committee of the Fifth Peoples Hospital of Shenyang, China (approval No. 20160301) and registered in the Chinese Clinical Trial Registry (registration number: ChiCTR1800014421). 展开更多
关键词 nerve REGENERATION CEREBRAL small vascular disease white matter HYPERINTENSITIES CEREBRAL hemodynamics CEREBRAL hypoperfusion middle CEREBRAL artery blood flow velocity breath-holding test breath-holding index cognitive function neural REGENERATION
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昆明烟区土壤线虫数量与环境因子的Mantel Test分析
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作者 施锘 李恩星 +9 位作者 陈江政 蒋碧霞 吴思昊 贺艳杰 王戈 王娜 白羽祥 周鹏 杜宇 李杰 《山东农业科学》 北大核心 2024年第10期153-158,共6页
为进一步明确昆明烟区影响线虫的环境因素,于2022年采集云南昆明烟区8个县(市、区)64个乡镇的320个植烟土壤样品,调查与测定样品采集地的海拔、土壤线虫数量以及土壤理化性质(pH值及有机质、水解性氮、速效钾和有效磷含量),并探讨土壤... 为进一步明确昆明烟区影响线虫的环境因素,于2022年采集云南昆明烟区8个县(市、区)64个乡镇的320个植烟土壤样品,调查与测定样品采集地的海拔、土壤线虫数量以及土壤理化性质(pH值及有机质、水解性氮、速效钾和有效磷含量),并探讨土壤线虫数量与植烟土壤环境因子之间的潜在关系。结果表明,昆明烟区土壤线虫数量一定程度上受到海拔及土壤理化性质的影响,海拔与有机质、水解性氮和速效钾呈显著正相关,pH值与有效磷呈极显著负相关,相关系数为-0.850;土壤线虫数量与土壤有效磷呈正相关,与海拔、pH值、有机质、水解性氮、速效钾呈负相关,其中与海拔、有机质和水解性氮的相关系数较大,分别为-0.751、-0.651和-0.568。通过Mantel test分析确定海拔、有机质和水解性氮含量是影响昆明烟区土壤线虫数量的重要因子。本结果可为有效防治土壤线虫提供科学依据。 展开更多
关键词 土壤线虫 海拔 土壤理化特性 Mantel test分析
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Failure characterization of fully grouted rock bolts under triaxial testing 被引量:1
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作者 Hadi Nourizadeh Ali Mirzaghorbanali +3 位作者 Mehdi Serati Elamin Mutaz Kevin McDougall Naj Aziz 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期778-789,共12页
Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic st... Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic stress conditions.Under these conditions,it is assumed that the intermediate principal stress(σ_(2))equals the minimum principal stress(σ_(3)).This assumption overlooks the potential variations in magnitudes of in situ stress conditions along all three directions near an underground opening where a rock bolt is installed.In this study,a series of push tests was meticulously conducted under triaxial conditions.These tests involved applying non-uniform confining stresses(σ_(2)≠σ_(3))to cubic specimens,aiming to unveil the previously overlooked influence of intermediate principal stresses on the strength properties of rock bolts.The results show that as the confining stresses increase from zero to higher levels,the pre-failure behavior changes from linear to nonlinear forms,resulting in an increase in initial stiffness from 2.08 kN/mm to 32.51 kN/mm.The load-displacement curves further illuminate distinct post-failure behavior at elevated levels of confining stresses,characterized by enhanced stiffness.Notably,the peak load capacity ranged from 27.9 kN to 46.5 kN as confining stresses advanced from σ_(2)=σ_(3)=0 to σ_(2)=20 MPa and σ_(3)=10 MPa.Additionally,the outcomes highlight an influence of confining stress on the lateral deformation of samples.Lower levels of confinement prompt overall dilation in lateral deformation,while higher confinements maintain a state of shrinkage.Furthermore,diverse failure modes have been identified,intricately tied to the arrangement of confining stresses.Lower confinements tend to induce a splitting mode of failure,whereas higher loads bring about a shift towards a pure interfacial shear-off and shear-crushed failure mechanism. 展开更多
关键词 Rock bolts Bolt-grout interface Bond strength Push test Triaxial tests
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Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models 被引量:1
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作者 Jian-Guo Li Bai-Shan Hu +1 位作者 Shuang Zhang Fu-Rong Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期1-2,共2页
The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting neutrons.The unbound feature of the heaviest oxygen isotope,^(28)O,provides an ... The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting neutrons.The unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear models.The atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N. 展开更多
关键词 testING QUANTUM system
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Micromechanical testing and property upscaling of planetary rocks:A critical review 被引量:2
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作者 Yiwei Liu Guoping Zhang +1 位作者 Jiangmei Qiao Xuhai Tang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1217-1241,共25页
Knowledge of the mechanical behavior of planetary rocks is indispensable for space explorations.The scarcity of pristine samples and the irregular shapes of planetary meteorites make it difficult to obtain representat... Knowledge of the mechanical behavior of planetary rocks is indispensable for space explorations.The scarcity of pristine samples and the irregular shapes of planetary meteorites make it difficult to obtain representative samples for conventional macroscale rock mechanics experiments(macro-RMEs).This critical review discusses recent advances in microscale RMEs(micro-RMEs)techniques and the upscaling methods for extracting mechanical parameters.Methods of mineralogical and microstructural analyses,along with non-destructive mechanical techniques,have provided new opportunities for studying planetary rocks with unprecedented precision and capabilities.First,we summarize several mainstream methods for obtaining the mineralogy and microstructure of planetary rocks.Then,nondestructive micromechanical testing methods,nanoindentation and atomic force microscopy(AFM),are detailed reviewed,illustrating the principles,advantages,influencing factors,and available testing results from literature.Subsequently,several feasible upscaling methods that bridge the micro-measurements of meteorite pieces to the strength of the intact body are introduced.Finally,the potential applications of planetary rock mechanics research to guiding the design and execution of space missions are environed,ranging from sample return missions and planetary defense to extraterrestrial construction.These discussions are expected to broaden the understanding of the microscale mechanical properties of planetary rocks and their significant role in deep space exploration. 展开更多
关键词 METEORITES Planetary rock mechanics Non-destructive testing Upscaling method Extraterrestrial construction Space exploration
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Electrochemical biosensors for point-of-care testing 被引量:1
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作者 Jinsol Kim Juho Jeong Seung Hwan Ko 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期548-565,共18页
Point-of-care testing(POCT)is the practice of diagnosing and monitoring diseases where the patient is located,as opposed to traditional treatment conducted solely in a medical laboratory or other clinical setting.POCT... Point-of-care testing(POCT)is the practice of diagnosing and monitoring diseases where the patient is located,as opposed to traditional treatment conducted solely in a medical laboratory or other clinical setting.POCT has been less common in the recent past due to a lack of portable medical devices capable of facilitating effective medical testing.However,recent growth has occurred in this field due to advances in diagnostic technologies,device miniaturization,and progress in wearable electronics.Among these developments,electrochemical sensors have attracted interest in the POCT field due to their high sensitivity,compact size,and affordability.They are used in various applications,from disease diagnosis to health status monitoring.In this paper we explore recent advancements in electrochemical sensors,the methods of fabricating them,and the various types of sensing mechanisms that can be used.Furthermore,we delve into methods for immobilizing specific biorecognition elements,including enzymes,antibodies,and aptamers,onto electrode surfaces and how these sensors are used in real-world POCT settings. 展开更多
关键词 Point-of-care testing(POCT) Electrochemical sensor ENZYME ANTIBODY Health care
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Aquifer Test求群孔抽水试验水文地质参数
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作者 李红伟 《中国高新科技》 2024年第5期56-57,129,共3页
在水文地质条件复杂的地区,往往采用大型的群孔抽水试验充分揭露含水层特征,获取水文地质参数。用Aquifer Test软件求解水文地质参数,则方便实用、简捷高效,可快速输出拟合图形和求参结果。Aquifer Test提供了丰富的求参方案,求参必须... 在水文地质条件复杂的地区,往往采用大型的群孔抽水试验充分揭露含水层特征,获取水文地质参数。用Aquifer Test软件求解水文地质参数,则方便实用、简捷高效,可快速输出拟合图形和求参结果。Aquifer Test提供了丰富的求参方案,求参必须结合当地当时的水文地质条件实际情况考虑,选择适合的方案和时空数据求取水文地质参数。 展开更多
关键词 群孔抽水试验 水文地质参数 Aquifer test
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