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Preferences for oral-vs blood-based human immunodeficiency virus self-testing:A scoping review of the literature
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作者 Victor Abiola Adepoju Winifred Imoyera Ali Johnson Onoja 《World Journal of Methodology》 2023年第3期142-152,共11页
BACKGROUND The evidence on preferences for oral-vs blood-based human immunodeficiency virus self-testing(HIVST)has been heterogenous and inconclusive.In addition,most evaluations have relied on hypothetical or stated ... BACKGROUND The evidence on preferences for oral-vs blood-based human immunodeficiency virus self-testing(HIVST)has been heterogenous and inconclusive.In addition,most evaluations have relied on hypothetical or stated use cases using discreet choice experiments rather than actual preferences among experienced users,which are more objective and critical for the understanding of product uptake.Direct head-to-head comparison of consumer preferences for oral-versus bloodbased HIVST is lacking.AIM To examine the existing literature on preferences for oral-vs blood-based HIVST,determine the factors that impact these preferences,and assess the potential implications for HIVST programs.METHODS Databases such as PubMed,Medline,Google Scholar,and Web of Science were searched for articles published between January 2011 to October 2022.Articles must address preferences for oral-vs blood-based HIVST.The study used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist to ensure the quality of the study.RESULTS The initial search revealed 2424 records,of which 8 studies were finally included in the scoping review.Pooled preference for blood-based HIVST was 48.8%(9%-78.6%),whereas pooled preference for oral HIVST was 59.8%(34.2%-91%)across all studies.However,for male-specific studies,the preference for blood-based HIVST(58%-65.6%)was higher than that for oral(34.2%-41%).The four studies that reported a higher preference for blood-based HIVST were in men.Participants considered blood-based HIVST to be more accurate and rapid,while those with a higher preference for oral HIVST did so because these were considered non-invasive and easy to use.CONCLUSION Consistently in the literature,men preferred blood-based HIVST over oral HIVST due to higher risk perception and desire for a test that provides higher accuracy coupled with rapidity,autonomy,privacy,and confidentiality,whereas those with a higher preference for oral HIVST did so because these were considered non-invasive and easy to use.Misinformation and distrust need to be addressed through promotional messaging to maximize the diversity of this new biomedical technology. 展开更多
关键词 Human immunodeficiency virus self-testing PREFERENCES Oral human immunodeficiency virus self-testing Blood-based human immunodeficiency virus self-testing
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Acceptability and strategies for enhancing uptake of human immunodeficiency virus self-testing in Nigeria
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作者 Victor Abiola Adepoju Chidinma Umebido +1 位作者 Ademola Adelekan Ali Johnson Onoja 《World Journal of Methodology》 2023年第3期127-141,共15页
BACKGROUND In 2019,the Nigerian Ministry of Health published the first operational guidelines for human immunodeficiency virus self-testing(HIVST)to improve access to human immunodeficiency virus(HIV)testing services ... BACKGROUND In 2019,the Nigerian Ministry of Health published the first operational guidelines for human immunodeficiency virus self-testing(HIVST)to improve access to human immunodeficiency virus(HIV)testing services among undertested populations in the country.Also,as part of the campaign to increase HIV testing services in Nigeria,the Nigerian Ministry of Health developed standard operating procedures for using HIVST kits.AIM To systematically review the acceptability and strategies for enhancing the uptake of HIVST in Nigeria.METHODS The systematic review was conducted and reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses.Different databases were searched to get the necessary materials needed for this review.Standardized forms developed by the authors were used for data extraction to minimize the risk of bias and ensure that the articles used for the study were properly screened.Identified articles were first screened using the titles and their abstracts.The full papers were screened,and the similarities of the documents were determined.Qualitative,quantitative,and mixed-method studies were evaluated using the Critical Appraisal Skills Programme and Critical Appraisal Framework criteria.RESULTS All the publications reviewed were published between 2015 and 2022,with 33.3%published in 2021.Most(77.8%)of the studies were cross-sectional,43.3%were conducted in Lagos State,and 26.3%were conducted among young people.The study revealed a high level of acceptability of HIVST.Certain factors,such as gender,sexual activity,and previous testing experience,influence the acceptability of HIV self-testing,with some individuals more likely to opt-out.The cost of the kit was reported as the strongest factor for choosing HIVST services,and this ranged from 200 to 4000 Naira(approximately United States Dollar 0.55-11.07),with the majority willing to pay 500 Naira(approximately United States Dollar 1.38).Privately-owned,registered pharmacies,youthfriendly centres,supermarkets,and online stores were the most cited access locations for HIVST.The least influential attribute was the type of specimen needed for HIVST.Strategies addressing cost and preferred access points and diverse needs for social media promotion,local translation of product use instructions,and HIVST distribution led by key opinion leaders for key populations were found to significantly enhance HIVST uptake and linkage to care.CONCLUSION HIVST acceptability is generally high from an intention-to-use perspective.Targeted strategies are required to improve the acceptability of HIV self-testing,especially among males,sexually active individuals,and first-time testers.Identified and proposed uptake-enhancing strategies need to be investigated in controlled settings and among different populations and distribution models in Nigeria. 展开更多
关键词 ACCEPTABILITY HIV self-testing UPTAKE Intention-to-use Regulation Linkage to care
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Uptake of HIV Self-testing among Men Who have Sex with Men in Beijing, China: a Cross-sectional Study 被引量:13
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作者 REN Xian Long WU Zun You +3 位作者 MI Guo Dong MCGOOGAN Jennifer ROU Ke Ming ZHAO Yan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第6期407-417,共11页
Objective To examine HIV self-testing uptake and its determinates among men who have sex with men (MSM) in Beijing, China. Methods A cross-sectional online survey was conducted in Beijing, China in 2016. Participant... Objective To examine HIV self-testing uptake and its determinates among men who have sex with men (MSM) in Beijing, China. Methods A cross-sectional online survey was conducted in Beijing, China in 2016. Participants were users of a popular Chinese gay networking application and had an unknown or negative HIV status. Univariate and multivariate logistic regression analyses were conducted to examine factors associated with HIV self-testing based on adjusted odds ratio (AOR) and 95% confidence interval (CI). Results Among the 5,996 MSM included in the study, 2,383 (39.7%) reported to have used HIV self-testing kits. Willingness to use an HIV self-test kit in the future was expressed by 92% of the participants. High monthly income (AOR = 1.49; CI = 1.10-2.02; P = 0.010), large number of male sex partners (≥2: AOR = 1.24; CI = 2.09-1.43; P = 0.002), sexual activity with commercial male sex partners (〉 2: AOR = 1.94; CI = 1.34 -2.82; P = 0.001), long-term drug use (AOR = 1.42; CI = 1.23-1.62; P 〈 0.001), and long-term HIV voluntary counseling and testing (VCT) attendance (AOR = 3.62; CI = 3.11-4.22; P 〈 0.001) were all associated with increased odds of HIV self-testing uptake. Conclusion The nearly 40% rate of HIV self-testing uptake among MSM in our sample was high. In addition, an over 90% willingness to use kits in the future was encouraging. HIV self-testing could be an important solution to help China achieve the global target of having 90% of all people living with HIV diagnosed by 2020. 展开更多
关键词 Men who have sex with men HIV self-testing Associated factors BEIJING
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Robustness self-testing of states and measurements in the prepare-and-measure scenario with 3 → 1 random access code
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作者 魏士慧 郭奋卓 +1 位作者 李新慧 温巧燕 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期144-151,共8页
Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(... Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(2018)].They realized the self-testing of preparations and measurements in an N → 1(N ≥ 2) random access code(RAC), and provided robustness bounds in a 2 → 1 RAC.Since all N → 1 RACs with shared randomness are combinations of 2 → 1 and 3 → 1 RACs, the3 → 1 RAC is just as important as the 2 → 1 RAC.In this paper, we find a set of preparations and measurements in the3 → 1 RAC, and use them to complete the robustness self-testing analysis in the prepare-and-measure scenario.The method is robust to small but inevitable experimental errors. 展开更多
关键词 ROBUSTNESS self-testING prepare-and-measure SCENARIO 3 1 random access CODE
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Efficient self-testing system for quantum computations based on permutations
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作者 马树泉 朱畅华 +1 位作者 聂敏 权东晓 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期61-73,共13页
Verification in quantum computations is crucial since quantum systems are extremely vulnerable to the environment.However,verifying directly the output of a quantum computation is difficult since we know that efficien... Verification in quantum computations is crucial since quantum systems are extremely vulnerable to the environment.However,verifying directly the output of a quantum computation is difficult since we know that efficiently simulating a large-scale quantum computation on a classical computer is usually thought to be impossible.To overcome this difficulty,we propose a self-testing system for quantum computations,which can be used to verify if a quantum computation is performed correctly by itself.Our basic idea is using some extra ancilla qubits to test the output of the computation.We design two kinds of permutation circuits into the original quantum circuit:one is applied on the ancilla qubits whose output indicates the testing information,the other is applied on all qubits(including ancilla qubits) which is aiming to uniformly permute the positions of all qubits.We show that both permutation circuits are easy to achieve.By this way,we prove that any quantum computation has an efficient self-testing system.In the end,we also discuss the relation between our self-testing system and interactive proof systems,and show that the two systems are equivalent if the verifier is allowed to have some quantum capacity. 展开更多
关键词 quantum computation VERIFICATION self-testing systems complexity theory
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Assessing the Acceptability and Willingness to Use HIV Self-Testing among Student Nurses in a Private Nursing College, Gauteng Province, South Africa
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作者 Sphiwe Madiba Molly Segobola Mathildah Mokgatle 《World Journal of AIDS》 2015年第3期208-216,共9页
Globally, there is increasing evidence that HIV self-testing (HIVST) is commonly practiced among health care workers (HCWs). Although HIVST kits are available in South Africa, their distribution and use remain unregul... Globally, there is increasing evidence that HIV self-testing (HIVST) is commonly practiced among health care workers (HCWs). Although HIVST kits are available in South Africa, their distribution and use remain unregulated and its acceptability, undocumented. The aim of the study was to explore the acceptability of HIV self-testing among student nurses, examine their willingness to use self-testing, and evaluate their views on the implementation of a regulated HIV self-testing programme. This was a qualitative explorative study, and six focus group discussions were conducted with 67 student nurses recruited from a private nursing college, in Pretoria, South Africa. Thematic analysis and NVivo10 qualitative software were used for data analysis. The nurses perceived HIVST as an acceptable option for HIV testing and most were willing to self-test. Self-testing will provide confidential and accessible HIV testing services, reduce the stigma associated with the condition, and increase partner testing and disclosure. HIVST is more likely to be practised if self-testing kits are easily accessible and affordable, and there are strategies to educate people before the adoption of HIVST. The lack of pre- and post-test counselling, the risk of inaccurate test results, and lack of strategies for the confirmation of self-testing results were the main arguments against HIVST. The high acceptance of HIVST among nurses suggests that HIVST is a feasible option to increase the uptake of HIV-testing among HCWs. However, pre- and post-test counselling should be considered important components in the implementation of self-testing services. Educational and awareness campaigns should precede the roll-out of the self-testing programs. 展开更多
关键词 HIV self-testING Nurses ACCEPTABILITY South AFRICA Health Care Workers
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Phase-Coding Self-Testing Quantum Random Number Generator
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作者 宋萧天 李宏伟 +5 位作者 银振强 梁文烨 张春梅 韩云光 陈巍 韩正甫 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期6-8,共3页
How to estimate the randomness of the measurement outcomes generated by a given device is an important issue in quantum information theory. Recently, Brunner et al. [Phys. Rev. Lett. 112 (2014)140407] proposed a pre... How to estimate the randomness of the measurement outcomes generated by a given device is an important issue in quantum information theory. Recently, Brunner et al. [Phys. Rev. Lett. 112 (2014)140407] proposed a prepare-and-measure quantum random number generation scenario with device-independent assumption, which indicates a method to test the randomness of bit strings according to the generation process rather than the results. Based on this protocol, we implement a quantum random number generator with an intrinsic stable phase-encoded quantum key distribution system. The system has been continuously running for more than 200 h, a stable witness W with the average value of 0.9752 and a standard deviation of 0.0024 are obtained. More than 1 G random bits are generated and the results pass all items of NIST test suite. 展开更多
关键词 Phase-Coding self-testing Quantum Random Number Generator
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HIV Self-Testing Kits Uptake in Mashonaland West Province, Zimbabwe, 2019-2020: A Secondary Data Analysis
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作者 Tendai Hlabangana Owen Mugurungi +5 位作者 Howard Nyika Emmanuel Govha Tsitsi Patience Juru Notion Tafara Gombe Addmore Chadambuka Mufuta Tshimanga 《World Journal of AIDS》 2022年第1期20-31,共12页
Background: Human Immuno-Deficiency Virus Self-Testing (HIVST) is a process where an individual who wants to know their HIV status collects a specimen, performs a test and interprets the result by themselves. HIVST da... Background: Human Immuno-Deficiency Virus Self-Testing (HIVST) is a process where an individual who wants to know their HIV status collects a specimen, performs a test and interprets the result by themselves. HIVST data from the Zimbabwe AIDS and TB Program (ATP) directorate showed that between 2019-2020, only 31% of the target HIVST kits were distributed in the country. Mashonaland West Province was one of the least performing provinces in meeting targets for HIVST kits distribution. Gaps in the implementation of the HIVST in the province ultimately affect the nationwide scaleup of targeted testing, a key enabler in achieving HIV epidemic control. We analyzed HIVST trends in Mashonaland West Province to inform HIV testing services programming. Methods: We conducted a cross-sectional study using HIVST secondary data obtained from the District Health Information Software 2 (DHIS2) electronic database. We conducted regression analysis for trends using Epi Info 7.2 and tables, bar graphs, pie charts and linear graphs were used for data presentation. Results: A total of 31,070 clients accessed HIVST kits in Mashonaland West Province from 2019-2020. A slightly higher proportion (50.4% and 51.7%) of females as compared to males accessed HIVST kits in 2019 and 2020 respectively. Overall, an increase in the trend of HIVST kits uptake was recorded (males R<sup>2</sup> = 0.3945, p-value = 0.003 and females R<sup>2</sup> = 0.4739, p-value = 0.001). There was generally a decline in the trend of community-based distribution of HIVST kits from the third quarter of 2019 throughout 2020 (R<sup>2</sup> = 0.2441, p-value = 0.006). Primary distribution of HIVST kits remained the dominant method of distribution, constituting more than half of the kits distributed in both 2019 (67%) and 2020 (86%). Conclusion: Mashonaland West Province was mainly utilising facility-based distribution model for HIVST over the community-based distribution model. We recommended training more community-based distribution agents to increase community distribution of HIVST kits. 展开更多
关键词 HIV self-testing Analysis Secondary Data
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An Adaptive Ramp Generator for ADC Built-in Self-Test 被引量:1
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作者 张娜 姚素英 张钰 《Transactions of Tianjin University》 EI CAS 2008年第3期178-181,共4页
An adaptive ramp generator based on linear histogram was proposed for the built-in selftest (BIST) of analog to digital convertor (ADC) in CMOS image sensor. By comparing the generated ramp signal to a reference volta... An adaptive ramp generator based on linear histogram was proposed for the built-in selftest (BIST) of analog to digital convertor (ADC) in CMOS image sensor. By comparing the generated ramp signal to a reference voltage and feeding back a calibration signal, the slope adjustment was implemented, and high linearity and precision of ramp slope were realized. By modulating the pulse width and reference voltage, sweep length varied from microsecond to second and signal swing could reach 3 V with 5.6 mW power consumption. The ramp was used as input to an ideal 10-bit single-slope ADC, and the corresponding DNL and INL were 0.032 LSB and 0.078 LSB, re-spectively. 展开更多
关键词 自适应发电机 自适应电路 内置自检验 积分电路
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Feasibility of a finger prick-based self-testing kit in first- and second-degree relatives of children with coeliac disease
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作者 Judith Pichler Matthias Zilbauer +3 位作者 Franco Torrente Robert Heuschkel Alan Phillips Camilla Salvestrini 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第14期1840-1843,共4页
AIM:To assess feasibility of a finger prick-based kit as method for self-testing of first and second-degree relatives of coeliac disease (CD) patients. METHODS:A total number of 379 subjects were invited to participat... AIM:To assess feasibility of a finger prick-based kit as method for self-testing of first and second-degree relatives of coeliac disease (CD) patients. METHODS:A total number of 379 subjects were invited to participate in this study,consisting of 197 first- degree and 182 second-degree relatives of CD patients. The self-testing kit (BiocardTM) was sent out with included instructions for use. Completed tests were sent back to the study coordinator for assessment. RESULTS:One hundred and ninety-six invited relatives carried out the BiocardTM test at home. Amongst these,70% were children. In 97% of the cases the test was performed correctly. Three tests revealed a positive result,all of which were later confirmed by serology and histology as coeliac disease.CONCLUSION:Our study indicates that BiocardTM test is a reliable,easy to use and well-accepted tool for home testing of first- and second-degree relatives of CD patients. 展开更多
关键词 检测试剂盒 第一代 腹腔 学位 疾病 儿童 手指 测试评估
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Multicenter evaluation of a simple and sensitive nucleic acid self-testing for SARS-CoV-2
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作者 Xin-Xin Shen Feng-Yu Li +6 位作者 Meng Qin Guo-Hao Zhang Meng-Yi Zhang Hong Liu Xiu-Li Sun Zhen-Jiang Xin Xue-Jun Ma 《Virologica Sinica》 SCIE CAS CSCD 2023年第4期620-626,共7页
A rapid and accurate COVID-19 diagnosis is a prerequisite for blocking the source of infection as soon as possible and taking the appropriate medical action.Herein,we developed GeneClick,a device for nucleic acid self... A rapid and accurate COVID-19 diagnosis is a prerequisite for blocking the source of infection as soon as possible and taking the appropriate medical action.Herein,we developed GeneClick,a device for nucleic acid self-testing of SARS-CoV-2,consisting of three modules:a sampling kit,a microfluidic chip-based disposable cartridge,and an amplification reader.In addition,we evaluated the clinical performance of GeneClick using 2162 nasal swabs collected at three medical institutions,using three commercial RT-qPCR kits and an antigen self-test as references.Compared to RT-qPCR,the sensitivity and specificity of the GeneClick assay were 97.93%and 99.72%,respectively,with a kappa value of 0.979(P<0.01).Of the 2162 samples,2076 were also tested for SARS-CoV-2 antigens.Among the 314 positive samples identified by GeneClick assay,63 samples were undetected by antigen tests.Overall,the GeneClick nucleic acid self-test demonstrated higher accuracy than the antigen-based detection.Based on the additional features,including simple operation,affordable price,portable device,and reliability of smartphone APP-driven sampling and result reporting,GeneClick offers a powerful tool for field-based SARS-CoV-2 detection in primary healthcare institutions or at-home use. 展开更多
关键词 Nucleic acid self-testing SARS-CoV-2 RT-QPCR Antigen-test
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Parallel Software-Based Self-Testing with Bounded Model Checking for Kilo-Core Networks-on-Chip
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作者 张颖 季鹏飞 +3 位作者 朱潘玮 Zebo Peng 李华伟 江建慧 《Journal of Computer Science & Technology》 SCIE EI CSCD 2023年第2期405-421,共17页
Online testing is critical to ensuring reliable operations of the next generation of supercomputers based on a kilo-core network-on-chip(NoC)interconnection fabric.We present a parallel software-based self-testing(SBS... Online testing is critical to ensuring reliable operations of the next generation of supercomputers based on a kilo-core network-on-chip(NoC)interconnection fabric.We present a parallel software-based self-testing(SBST)solution that makes use of the bounded model checking(BMC)technique to generate test sequences and parallel packets.In this method,the parallel SBST with BMC derives the leading sequence for each router’s internal function and detects all functionally-testable faults related to the function.A Monte-Carlo simulation algorithm is then used to search for the approximately optimum configuration of the parallel packets,which guarantees the test quality and minimizes the test cost.Finally,a multi-threading technology is used to ensure that the Monte-Carlo simulation can reach the approximately optimum configuration in a large random space and reduce the generating time of the parallel test.Experimental results show that the proposed method achieves a high fault coverage with a reduced test overhead.Moreover,by performing online testing in the functional mode with SBST,it effectively avoids the over-testing problem caused by functionally untestable turns in kilo-core NoCs. 展开更多
关键词 software-based self-testing(SBST) parallel test kilo-core networks-on-chip(NoCs) online testing
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一种基于分压电路的绑定后TSV测试方法
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作者 刘军 项晨 +1 位作者 陈田 吴玺 《微电子学与计算机》 2024年第4期132-140,共9页
对硅通孔(Through Silicon Via,TSV)进行绑定后测试可以有效地提升三维集成电路的性能和良率。现有的测试方法虽然对于开路和桥接故障的测试能力较高,但是对于泄漏故障的测试效果较差,并且所需的总测试时间较长。对此,提出了一种基于分... 对硅通孔(Through Silicon Via,TSV)进行绑定后测试可以有效地提升三维集成电路的性能和良率。现有的测试方法虽然对于开路和桥接故障的测试能力较高,但是对于泄漏故障的测试效果较差,并且所需的总测试时间较长。对此,提出了一种基于分压电路的TSV绑定后测试方法。该方法设计了一种分压电路,进行泄漏故障测试时可以形成一条无分支的电流路径,有效提高了对泄漏故障的测试能力。此外,该方法测试开路故障和泄漏故障时的电流路径不会相互干扰,可以同时测试相邻TSV的开路故障和泄漏故障。实验结果表明,该方法可以测试10 kΩ以下的弱泄漏故障,并且在工艺偏差下依然能够保持较高的测试能力。相比同类测试方法,该方法所需面积开销更小,所需总测试时间更少。 展开更多
关键词 三维集成电路 硅通孔 绑定后测试 内建自测试
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PB840呼吸机气路分析及故障维修
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作者 曲超 李首峰 《中国医疗设备》 2024年第7期176-180,共5页
呼吸机是一种能替代患者自主通气的医疗仪器,广泛应用于呼吸衰竭患者、呼吸支持治疗以及急救复苏过程,是医院急诊、重症加强护理病房最重要的抢救仪器。本文介绍了2例PB840呼吸机故障,故障现象均为呼吸机报警、停止送气,报警代码相似。... 呼吸机是一种能替代患者自主通气的医疗仪器,广泛应用于呼吸衰竭患者、呼吸支持治疗以及急救复苏过程,是医院急诊、重症加强护理病房最重要的抢救仪器。本文介绍了2例PB840呼吸机故障,故障现象均为呼吸机报警、停止送气,报警代码相似。第1例故障经过呼吸机扩展自检(Extenden Self Test,EST)后分析自检数据,发现为呼出端流量传感器Q3故障,经过柠檬酸浸泡处理Q3后故障解除;第2例故障为氧气调零流量检测失败,具体原因为氧比例电磁阀故障,更换配件后故障解除。通过两例故障提示维修人员需熟悉仪器的气路图,熟练掌握呼吸机EST方法,提高维修准确度。 展开更多
关键词 PB840呼吸机 气路分析 扩展自检 流量传感器
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膨润土浆液及其自凝灰浆黏度微观机理研究
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作者 江志安 张宝增 +1 位作者 崔溦 苗日成 《人民黄河》 CAS 北大核心 2024年第8期149-154,共6页
不同厂家生产的钠基膨润土在相同配比要求下制备的自凝灰浆黏度差别很大,其本质是材料微观组分、结构不一致。基于SEM、XRD、EDS与NMR等微观试验,对两个厂家生产的同类钠基膨润土(简称湘源土和玉龙土)及其所制自凝灰浆进行试验分析,并... 不同厂家生产的钠基膨润土在相同配比要求下制备的自凝灰浆黏度差别很大,其本质是材料微观组分、结构不一致。基于SEM、XRD、EDS与NMR等微观试验,对两个厂家生产的同类钠基膨润土(简称湘源土和玉龙土)及其所制自凝灰浆进行试验分析,并据此对其黏度微观机理进行研究。结果如下:湘源土和玉龙土浆液黏度具有触变性,“卡片宫”的建立与Q~4结构的生成会促使其黏度上升,剪切作用会破坏微观结构使其黏度降低;湘源土蒙脱石含量高于玉龙土的,所以其浆液黏度整体高于玉龙土浆液。搅拌与低剪切作用促进蒙脱石颗粒小片层分散,小片层分散越多,停止剪切后膨润土浆液黏度越高。对于膨润土所制自凝灰浆,其黏度的变化主要依赖于内部电荷吸附与水化反应的程度,水化反应生成的C-S-H凝胶会促进浆液黏度提高。自凝灰浆在凝结过程中生成的碳硫硅酸钙不利于C-S-H凝胶生成,湘源土自凝灰浆碳硫硅酸钙含量高于玉龙土自凝灰浆的,所以其整体黏度低于玉龙土自凝灰浆的。 展开更多
关键词 膨润土 自凝灰浆 黏度 微观试验 机理
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预应力CFRP布加固混凝土梁受弯试验
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作者 于玲 王泽鹏 +2 位作者 任成明 包龙生 王宇 《沈阳建筑大学学报(自然科学版)》 CAS 北大核心 2024年第2期241-249,共9页
目的 研究不同加固方法下预应力碳纤维布加固混凝土梁的受弯性能,解决桥梁加固缺陷的问题。方法 制作了5根试验梁,其中一根为对比梁,不做任何加固处理,其余4根分别采用不同的锚固方式、不同的初始张拉力及不同的加固位置进行加固,通过... 目的 研究不同加固方法下预应力碳纤维布加固混凝土梁的受弯性能,解决桥梁加固缺陷的问题。方法 制作了5根试验梁,其中一根为对比梁,不做任何加固处理,其余4根分别采用不同的锚固方式、不同的初始张拉力及不同的加固位置进行加固,通过控制变量,进行加载试验,分析其受弯性能的差异。结果 经加固后的试验梁承载能力与刚度明显增加,与对比梁相比,极限荷载分别提升了25%、22.06%、30.78%及36.76%;各试验梁达到屈服荷载时,经加固的试验梁挠度均小于对比梁产生的挠度,且模腔自锁式锚具锚固的试验梁挠度小于穿孔式自锁锚具锚固的试验梁挠度,相同锚固方法下初始张拉力较大的试验梁挠度要小于初始张拉力较小的试验梁挠度。结论 使用预应力碳纤维布加固混凝土梁能够有效提高混凝土梁的抗弯性能,提升效果与加固位置、锚固方式及初始张拉力大小有关。 展开更多
关键词 预应力碳纤维布 桥梁加固 受弯试验 缠绕自锁式锚具
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PC钢棒-钢筋混合配筋混凝土柱抗震性能试验研究
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作者 张香成 吴治莼 +4 位作者 李小鹏 赵军 赵佳宝 王春光 刘明阳 《振动与冲击》 EI CSCD 北大核心 2024年第15期133-141,共9页
为研究预应力混凝土用钢棒(steel bar for prestressed concrete, PC钢棒)-钢筋混合配筋混凝土柱的抗震性能,设计制作了5根相同尺寸、相同纵筋配筋率、不同PC钢棒替代率的PC钢棒-钢筋混合配筋混凝土柱试件,通过拟静力试验研究了PC钢棒... 为研究预应力混凝土用钢棒(steel bar for prestressed concrete, PC钢棒)-钢筋混合配筋混凝土柱的抗震性能,设计制作了5根相同尺寸、相同纵筋配筋率、不同PC钢棒替代率的PC钢棒-钢筋混合配筋混凝土柱试件,通过拟静力试验研究了PC钢棒替代率对试件抗震性能的影响规律。结果表明:随着PC钢棒替代率的提高,试件的裂缝分布高度降低,裂缝数量变少,滞回曲线的饱满程度逐渐降低,耗能能力降低,残余位移角减小,自复位能力增强;当PC钢棒的替代率不大于50%时,各试件的峰值荷载接近;当PC钢棒的替代率大于50%时,试件的峰值荷载随PC钢棒替代率的增大而提高;当加载位移角相同且不大于1.0%时,配置PC钢棒的混凝土柱的残余位移角较为接近,且明显小于未配置PC钢棒的钢筋混凝土柱的残余位移角;当加载位移角相同且大于1%时,柱的残余位移角随着PC钢棒替代率的增高而降低。 展开更多
关键词 PC钢棒 混凝土柱 拟静力试验 抗震性能 自复位性能
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国家对非国家行为体行使自卫权的国际法律问题研究
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作者 廖丽 秦冰燚 《中国软科学》 CSCD 北大核心 2024年第8期71-82,共12页
随着全球化和国际事务的不断演变,非国家行为体在国际关系中的角色愈发凸显。本文探讨国家是否有权对非国家行为体行使自卫权的问题,认为国际法并未明确排除面对武力攻击时国家对非国家行为体行使自卫权的可能,同时指出尽管“不愿或不... 随着全球化和国际事务的不断演变,非国家行为体在国际关系中的角色愈发凸显。本文探讨国家是否有权对非国家行为体行使自卫权的问题,认为国际法并未明确排除面对武力攻击时国家对非国家行为体行使自卫权的可能,同时指出尽管“不愿或不能”测试在维护受害国国家安全和非国家行为体所在领土国主权之间保持了微妙平衡,但这个学说缺乏学理支撑且国际上未形成法律确信,自卫权行使仍需遵循“必要性”和“相称性”原则。因此,在面临来自非国家行为体的武力攻击时,国家有权采取包括自卫权在内的必要行动来维护国家安全,但各国必须深化在国际和地区事务中的沟通协作,捍卫以国际法为基础的国际秩序,确保自卫权的行使符合国际社会的共同利益和国际和平与安全的目标。 展开更多
关键词 非国家行为体 武力攻击 自卫权 “不愿或不能”测试
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蒺藜苜蓿MtCIM基因结构和功能分析 被引量:1
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作者 谢宏 周丽莹 +3 位作者 李舒文 王梦迪 艾晔 晁跃辉 《生物技术通报》 CAS CSCD 北大核心 2024年第1期262-269,共8页
【目的】CIM(cytokinin induce messager)属于Expansin蛋白家族,该蛋白是一类在植物生长和发育过程中起关键作用的蛋白质。为分析蒺藜苜蓿MtCIM基因结构、表达、亚细胞定位及在植物生长和发育过程中的功能。【方法】利用生物信息学工具... 【目的】CIM(cytokinin induce messager)属于Expansin蛋白家族,该蛋白是一类在植物生长和发育过程中起关键作用的蛋白质。为分析蒺藜苜蓿MtCIM基因结构、表达、亚细胞定位及在植物生长和发育过程中的功能。【方法】利用生物信息学工具对其进行深入分子量、理论等电点、不稳定系数及蛋白质结构预测和分析;同时,利用RT-qPCR方法,对不同激素处理(IAA、ABA、GA3)下的基因表达进行了检测;并通过融合蛋白瞬时表达及酵母表达方法鉴定其亚细胞定位及转录自激活情况;对MtCIM转基因植株进行低磷环境的适应分析。【结果】生物信息学分析显示,CIM蛋白的相对分子量为29.563 kD,理论等电点为5.54,不稳定系数为41.62,其蛋白质性质不稳定。二级及三级结构预测表明,该蛋白主要由无规则卷曲构成。外施IAA能够显著提高MtCIM的表达,外施ABA和GA3后,MtCIM表达呈现先升高后降低的趋势。亚细胞定位结果显示,其定位于细胞质中。对MtCIM进行转录自激活活性分析显示,蒺藜苜蓿MtCIM不存在自激活活性。对获得的20株转基因株系进行分析表明,转基因株系叶片细胞壁更厚;转基因植株对低磷环境具有更好的适应能力。【结论】对蒺藜苜蓿MtCIM的全面分析,揭示了其作为Expansin蛋白家族成员在植物生长和发育中的关键作用,并提高了植物在低磷环境中适应能力。 展开更多
关键词 蒺藜苜蓿 MtCIM基因 自激活检测 表达分析 亚细胞定位 低磷响应
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大规模芯片内嵌存储器的BIST测试方法研究
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作者 葛云侠 陈龙 +3 位作者 解维坤 张凯虹 宋国栋 奚留华 《国外电子测量技术》 2024年第5期18-25,共8页
随着大规模芯片的块存储器(block random access memory,BRAM)数量不断增多,常见的存储器内建自测试(memory build-in-self test,Mbist)方法存在故障覆盖率低、灵活性差等问题。为此,提出了一种新的基于可编程有限状态机的Mbist方法,通... 随着大规模芯片的块存储器(block random access memory,BRAM)数量不断增多,常见的存储器内建自测试(memory build-in-self test,Mbist)方法存在故障覆盖率低、灵活性差等问题。为此,提出了一种新的基于可编程有限状态机的Mbist方法,通过3个计数器驱动的可编程Mbist控制模块和算法模块集成8种测试算法,提高故障覆盖率和灵活性。采用Verilog语言设计了所提出的Mbist电路,通过Modelsim对1 Kbit×36的BRAM进行仿真并在自动化测试系统上进行了实际测试。实验结果表明,该方法对BRAM进行测试能够准确定位故障位置,故障的检测率提高了15.625%,测试效率提高了26.1%,灵活性差的问题也得到了很大改善。 展开更多
关键词 大规模芯片 块存储器 存储器内建自测试 可编程存储器内建自测试控制器 故障覆盖率
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