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Test and Evaluation of Relative Humidity Forecast in Each Competition Area of the "14 th National Winter Games" by Intelligent Forecasting Methods
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作者 Sitong LIU Xuefeng YANG 《Meteorological and Environmental Research》 2025年第1期37-40,共4页
Based on ground observation data of relative humidity,the prediction performance of STNF and MIFS in each competition area during February 13-26,2024 was tested and evaluated by using two intelligent forecasting metho... Based on ground observation data of relative humidity,the prediction performance of STNF and MIFS in each competition area during February 13-26,2024 was tested and evaluated by using two intelligent forecasting methods(STNF and MIFS).The results show that STNF had better performance in forecasting relative humidity in high-altitude areas,and was suitable for fine forecasting under complex terrain.MIFS improved the short-term forecast of some low-altitude stations,but the long-term reliability was insufficient.STNF method performed better than MIFS during 0-24 h.As the prediction time extended to 24-72 h,the errors of both methods showed a systematic increase trend.STNF had higher precision,lower root mean square error and smaller mean error in most regions under the background of most weather systems,showing its superiority as a forecasting method of relative humidity.However,the precision of MIFS was slightly higher than that of STNF in Liangcheng without system background,revealing that MIFS may also be an effective option in some specific conditions. 展开更多
关键词 Intelligent forecast Relative humidity Model test
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Magnetic pulse welding of Al-5754 with Al-7075 and MARS 380:Weldability windows and ballistic testing
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作者 Benoit Lagain Thomas Heuzé +1 位作者 Guillaume Racineux Michel Arrigoni 《Defence Technology(防务技术)》 2026年第1期64-79,共16页
Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining... Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining technique that overcomes these issues by using impact to create strong bonds without melting the substrate materials.This study investigates the weldability of aluminum alloy Al-5754 with Al-7075 and MARS 380 steel,used in armouring solutions of defense systems,by the use of MPW.In this work,weldability windows are investigated by varying standoff distances between the coating material and its substrate(0.25-4.5 mm)and discharge energies(5-13 kJ)with both O-shape and U-shape inductors.Mechanical strength of the welded joints were assessed through single lap shear tests,identifying optimal welding parameters.Then,the velocity profiles of the flyer plates were measured using heterodyne velocimetry to understand the dynamics of the impact.Then,substructures assembled with the optimal welding conditions were subjected to ballistic testing using 7.62 mm×51 mm NATO and 9 mm×19 mm Parabellum munitions to evaluate the resilience of the welds under ballistic impact.The outcomes demonstrate that MPW effectively joins Al-5754 with both Al-7075 and MARS 380,producing robust welds capable of withstanding ballistic impacts under certain conditions.This research advances the application of MPW in lightweight ballistic protection of defense systems,contributing to the development of more resilient and lighter protective structures. 展开更多
关键词 Magnetic pulse welding(MPW) Dissimilar material joining Weldability windows Impact welding Ballistic testing
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Key role of Levitt’s carbon monoxide breath test in revealing coexistent Gilbert syndrome and erythropoietic protoporphyria:A case report
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作者 Ling-Ling Kang Hou-De Zhang 《World Journal of Clinical Cases》 2026年第1期28-33,共6页
It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and er... It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and erythropoietic protoporphyria(EPP),which has not been previously documented.CASE SUMMARY We present a rare case of coexisting GS and EPP in a 23-year-old Chinese male with a long history of jaundice and recently found splenomegaly.Serial nonspecific hemolysis screening tests yielded inconsistent results,and investigations for common hemolytic etiologies were negative.However,Levitt’s carbon monoxide breath test,which measures erythrocyte lifespan(the gold-standard marker of hemolysis),demonstrated significant hemolysis,revealing a markedly shortened erythrocyte lifespan of 11 days(normal average 120 days).Genetic testing subsequently confirmed EPP with a homozygous ferrochelatase gene mutation and GS with a heterozygous uridine diphosphate glucuronosyl trans-ferase 1A1 gene mutation.CONCLUSION The rapid,non-invasive Levitt’s carbon monoxide breath test resolved the diagnostic challenge posed by a rare and complex cause of hyperbilirubinemia. 展开更多
关键词 Isolated hyperbilirubinemia Erythropoietic protoporphyria Gilbert syndrome HEMOLYSIS Levitt’s carbon monoxide breath test Erythrocyte lifespan Case report
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Methodology to Evaluate Fatigue Damage of High-Speed Train Welded Bogie Frames Based on On-Track Dynamic Stress Test Data 被引量:5
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作者 Guangxue Yang Meng Wang +1 位作者 Qiang Li Ran Ding 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期181-188,共8页
The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. ... The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. In this paper, a new method was established to compute the equivalent stress amplitude to evaluate the fatigue damage based on the measurable randomness, since the equivalent stress is the key parameter for assessment of structure fatigue life and load derivation. The equivalent stress amplitude of a high-speed train welded bogie frame was found to obey normal distribution under uniform operation route that verified by on-track dynamic stress data, and the proposed model is, in effect, an improved version of the mathematical model used to calculate the equivalent stress amplitude. The data of a long-term, on-track dynamic stress test program was analyzed to find that the normal distribution parameters of equivalent stress amplitude values differ across different operation route. Thus, the fatigue damage of the high-speed train welded bogie frame can be evaluated by the proposed method if the running schedule of the train is known a priori. The results also showed that the equivalent stress amplitude of the region connected to the power system is more random than in other regions of the bogie frame. 展开更多
关键词 Fatigue damage evaluation Equivalent STRESS amplitude On-track dynamic STRESS test WELDED BOGIE frame of high-speed train
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Value of a new stick-type rapid urine test for the diagnosis of Helicobacter pylori infection in the Vietnamese population 被引量:4
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作者 Duc T Quach Toru Hiyama +5 位作者 Fumio Shimamoto Quang D Le Linh X Ho Nhu HT Vu Masaharu Yoshihara Naomi Uemura 《World Journal of Gastroenterology》 SCIE CAS 2014年第17期5087-5091,共5页
AIM: To assess the value of a new test for the diagnosis of Helicobacter pylori (H. pylori) infection, Rapirun<sup>&#x000ae;</sup>H. pylori Antibody Stick (Rapirun<sup>&#x000ae;</sup> S... AIM: To assess the value of a new test for the diagnosis of Helicobacter pylori (H. pylori) infection, Rapirun<sup>&#x000ae;</sup>H. pylori Antibody Stick (Rapirun<sup>&#x000ae;</sup> Stick), in a Vietnamese population. 展开更多
关键词 Helicobacter pylori Urine test Rapirun® Stick Vietnamese Rapid urease test
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Evaluation of genotoxicity of Trois through Ames and in vitro chromosomal aberration tests
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作者 Manu Chaudhary Anurag Payasi 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第11期902-906,共5页
Objective:To investigate the mutagenic potential of Trois using the bacterial reverse mutation assay(Ames test)and in vitro chromosomal aberration test.Methods:The ability of Trois to induce reverse mutations was eval... Objective:To investigate the mutagenic potential of Trois using the bacterial reverse mutation assay(Ames test)and in vitro chromosomal aberration test.Methods:The ability of Trois to induce reverse mutations was evaluated in Salmonella lyphimurium(TA 98,TA100,TAI535 and TA1537)and Escherichia coli(WP2 uvrA)with and without metabolic activation system(S9 mix)at the dose range of 313 to 5000μg/plate.Chromosomal aberrations were evaluated in Chinese hamster lung(CHL)cell line at the dose levels of 15,7.5,3.7,1.9 and 0.9 mg/mL in the absence and presence of S9 mix.Results:There were no increases in the number of revertant colonies at any concentrations of Trois used in the study with and without S9 mix in all tester strains.Trois did not produce any structural aberration in CHL cells in the presence or absence of S9 mix.Conclusions:Results of this study suggest that Trois is non-mutagenic. 展开更多
关键词 Trois ames test CHROMOSOMAL ABERRATION test
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Ames Test of Protein-modified Enterococcus faecalis
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作者 Lijun DING Shasha ZHAO 《Agricultural Biotechnology》 CAS 2019年第1期78-79,共2页
The potential mutagenicity of protein-modified Enterococcus faecalis was evaluated by the Ames test. The test subject was designed with 0. 05,0. 5,5. 0,and 50. 0 mg/dish doses,and a control group was set. With Salmone... The potential mutagenicity of protein-modified Enterococcus faecalis was evaluated by the Ames test. The test subject was designed with 0. 05,0. 5,5. 0,and 50. 0 mg/dish doses,and a control group was set. With Salmonella typhimurium mutant strains TA97,TA98,TA100 and TA102 as test strains,the Ames test was carried out with( +) or without(-) S9,and the number of revertant colonies was counted. The results showed that for the protein-modified E. faecalis in the case of + S9 and-S9,the average numbers of revertant colonies of the four test strains were less than two times of that of the negative control group,and no dose-response relationship was observed. The protein-modified E. faecalis was tested to be negative in the Ames test,indicating that the test substance was not mutagenic in vitro. 展开更多
关键词 Protein-modified ENTEROCOCCUS FAECALIS ames test
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Investigation of the Mutagenic Potential of Immunomodulator Arglabin Native in Tablets in the Ames Test
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作者 Khorlan I. Itzhanova Roza B. Seidakhmetova Sergazy M. Adekenov 《Journal of Pharmacy and Pharmacology》 2018年第8期790-795,共6页
The mandatory preclinical safety evaluation is an essential prerequisite to obtain the qualitative and effective medicines. Due to the fact that drugs may reveal genotoxic properties, the investigation of their mutage... The mandatory preclinical safety evaluation is an essential prerequisite to obtain the qualitative and effective medicines. Due to the fact that drugs may reveal genotoxic properties, the investigation of their mutagenic activity is an obligatory part of the preclinical drug safety program. The aim of the research is to study mutagenic properties of a new original immunomodulator Arglabin native in tablets in the induced test of gene mutations (the Ames test) on Salmonella typhimurium strains. Materials and methods: Four strains of S. typhimurium TA98, TA100, TA1535, and TA1537 were used to assess the mutagenicity in the Ames test. Results and conclusions: No statistically reliable dose-dependent increase in the number of revertant colonies of Salmonella typhimurium has been observed in the presence of the given drug within the investigated dose ranges from 5.0 to 100.0 μg/mL for strains TA100 and TA1535, and from 5.0 to 250 μg/mL for strains TA98 and TA1537 against the baseline of spantaneous mutations. Arglabin native in tablets does not reveal a mutagenic activity within the studied dose ranges on Salmonella typhimurium strains TA98, TA100, TA1535, TA1537. 展开更多
关键词 Arglabin native the ames test mutagenic properties.
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基于波形比对TestBench的Verilog在线自动测试系统设计 被引量:1
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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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Determination of Genotoxic Pollution of Some Hospital Wastewater with Salmonella Ames Test
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作者 Ali Riza Atasoy Engin Karakece +2 位作者 Mustafa Petek Lokman Alpsoy Abdullah Kiran 《Journal of Water Resource and Protection》 2012年第10期859-865,共7页
Wastewater of hospitals contains materials that would be a threat to alive. These water needs to be checked by a biological purification before leaving to nature. Hospital wastewater has differences than domestic wast... Wastewater of hospitals contains materials that would be a threat to alive. These water needs to be checked by a biological purification before leaving to nature. Hospital wastewater has differences than domestic waste because of especially blood, body waste, drugs, chemicals, medical device waste and radioactive materials. We aimed to determine genotoxic effects of total pollution in hospital wastewater on alive by Salmonella microsome test method. In this study, we decided on three hospitals which weren’t checked as biological purification of waste. The samples were taken for six 1-week periods between March 2009 and June 2009. Mutagenite studies of samples taken from hospitals were made with ,Salmonella typhimurium TA 98 and TA 100. Wastewater samples were evaporated. 27 different test materials were prepared using DMSO, ethanol and acetone solvents, two different MGA plaques were used for each test material. Each experiment was made for 3 times with known results of mutagens and we made it ready for “Ames” test method. We had genotoxicity 50% in Istanbul University Medical Faculty Hospital, 56% in Haseki Hospital and 61% in Vak?f Gureba Hospital. According to three hospitals result there are 9 positives, 9 negatives in DMSO;9 positives, 9 negatives in ethanol;12 positives, 6 negatives in acetone. These values are totally 56%. Our results give important information about mutagenic effect of total pollution in hospital wastewater. It is first time researched in Turkey that effect on DNA of pollution is from hospital wastewaters. In prospective studies, it is necessary to use this system as a method to monitor mutagenic genotoxic pollution in hospital wastewaters. These kinds of studies present applicability and importance of our method because of placing in the literature. Method constitutes a new approach to check mutagenite of pollution in hospital wastewater. 展开更多
关键词 Hospital Wastewater ames test TA 98 TA 100 GENOTOXICITY
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基于ETest的嵌入式软件测试应用与实践
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作者 赵聚雪 郑楚锋 《工业控制计算机》 2025年第9期48-50,共3页
随着技术的发展,嵌入式产品越来越丰富,为了保障嵌入式软件的质量,对嵌入式软件测试的研究也越来越多,探索了国产半实物仿真测试平台ETest开展嵌入式软件测试的应用过程,并对嵌入式软件测试与Web应用软件测试的异同进行了简要分析。
关键词 Etest 嵌入式软件 软件测试 WEB
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Conceptual study of X-braced frames with different steel grades using cyclic half-scale tests
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作者 Parviz Ebadi Saeid Sabouri-Ghomi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第3期313-329,共17页
In this paper, an experimental and analytical study of two half-scale steel X-braced flames with equal nominal shear strength under cyclic loading is described. In these tests, all members except the braces are simila... In this paper, an experimental and analytical study of two half-scale steel X-braced flames with equal nominal shear strength under cyclic loading is described. In these tests, all members except the braces are similar. The braces are made of various steel grades to monitor the effects of seismic excitation. Internal stiffeners are employed to limit the local buckling and increase the fracture life of the steel bracing. A heavy central core is introduced at the intersection of the braces to decrease their effective length. Recent seismic specifications are considered in the design of the X-braced frame members to verify their efficiency. The failure modes of the X-braced frames are also illustrated. It is observed that the energy dissipation capacity, ultimate load capacity and ductility of the system increase considerably by using lower grade steel and proposed detailing. Analytical modeling of the specimens using nonlinear finite element software supports the experimental findings. 展开更多
关键词 BRACING low grade steel EXPERIMENTATION cyclic test seismic behavior analytical modeling DUCTILITY
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STUDIES ON 15 HOME-MADE ANTIFERTILITY DRUGS BY AMES TEST
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《癌变·畸变·突变》 CAS CSCD 1991年第S1期201-201,共1页
15 home-made antifertility drugs havebeen studied by Ames test.They are AF-53,Estradiol volerate,Ethinyl Estradiol,Hy-droxyprogesterone caproate,Hydroxyproges-ten compound injection,Megestrol Aceta-te,Megestrol compou... 15 home-made antifertility drugs havebeen studied by Ames test.They are AF-53,Estradiol volerate,Ethinyl Estradiol,Hy-droxyprogesterone caproate,Hydroxyproges-ten compound injection,Megestrol Aceta-te,Megestrol compound tablet。 展开更多
关键词 Aceta TABLET ames ELECTIVE
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DETECTING THE MUTAGENICITY OF ACIDIUM MANDELICUM BY WAY OF AMES TEST
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《癌变·畸变·突变》 CAS CSCD 1991年第S1期88-88,共1页
Acidium mandelicum(AM) was used as an urinaryantiseptics in the 1930’.Recently,through laboratoryexperiment and clinical use,we have found AM tohave spermicide effect and possess special contra-ceptive mechanism.Thus... Acidium mandelicum(AM) was used as an urinaryantiseptics in the 1930’.Recently,through laboratoryexperiment and clinical use,we have found AM tohave spermicide effect and possess special contra-ceptive mechanism.Thus,it may be a reliable contra-ceptive.As any mutagenicity-positive material 展开更多
关键词 contra mater chose turned ames
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Ames试验阳性结果原因及后续试验方法选择的研究进展 被引量:1
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作者 吴辉 耿兴超 +1 位作者 李晓瑜 文海若 《癌变·畸变·突变》 2025年第1期85-88,F0003,共5页
遗传毒性试验是药物非临床安全性评价的重要组成部分,主要用于药物早期致癌性风险评价。近年来,新靶点和创新药效结构的药物大量涌现,遗传毒性或致癌性结果呈阳性的创新药物数量大幅增加。然而,有研究显示细菌回复突变试验(Ames)结果为... 遗传毒性试验是药物非临床安全性评价的重要组成部分,主要用于药物早期致癌性风险评价。近年来,新靶点和创新药效结构的药物大量涌现,遗传毒性或致癌性结果呈阳性的创新药物数量大幅增加。然而,有研究显示细菌回复突变试验(Ames)结果为阳性的化合物中约1/3为非致癌物。本文回顾了致突变性与致癌性风险间的关联,Ames试验阳性结果的原因及当前国际上对Ames试验阳性结果的药物的监管要求,总结了可供选择的后续体内试验方法,并提出当药物在非临床安全性评价中Ames试验结果为阳性时的评价思路和机制研究策略,为药物研发及评价提供借鉴。 展开更多
关键词 ames试验 阳性结果 后续试验 转基因啮齿动物 Pig-a基因突变试验 下一代测序
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Seismic performance testing of reinforcement concrete frames strengthened with Y-eccentrically brace
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作者 王大鹏 YU An-lin XUE Li-ming 《Journal of Chongqing University》 CAS 2012年第4期151-160,共10页
Two single-storey single-span reinforcement concrete (RC) frame structures strengthened with Y-eccentrically brace were designed and manufactured to be 1/3 scale. The pseudo-dynamic testing method was used to study ... Two single-storey single-span reinforcement concrete (RC) frame structures strengthened with Y-eccentrically brace were designed and manufactured to be 1/3 scale. The pseudo-dynamic testing method was used to study the mechanical characteristics and the seismic performance under E1-Centro earthquake action with different peak acceleration adjusted by China's Code for Seismic Design of Buildings. The test results indicate that RC frame structures strengthened with Y- eccentrically steel brace present perfect seismic performance under strong earthquake action owing to the good ductility, strong bearing capability and fine energy absorbing capability provided by energy dissipation element and high lateral stiffness provided by diagonal braces. The seismic performance is also affected by the length of outsourcing steel at the joint between energy dissipation element of eccentric steel brace and RC frame beam. The joint should be considerably designed to make sure that shear failure can firstly occur in energy dissipation element. 展开更多
关键词 Y-eccentrically steel brace energy dissipation element pseudo-dynamic test seismic performance shear failure
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Research of NOx Sensors Performance Test 被引量:1
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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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基于Siamese网络的油田业务试题相似度计算方法
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作者 尚福华 马文博 +1 位作者 解红涛 杜睿山 《计算机与数字工程》 2025年第3期870-876,共7页
由于对试题进行相似度检测可以有效地提高题库中试题质量,针对油田业务试题专业性及逻辑性强、包含字母和数字等的特点,且现存的相似度计算方法不能很好地挖掘其深层语义信息,论文提出了一种基于Siamese网络的油田业务试题相似度计算方... 由于对试题进行相似度检测可以有效地提高题库中试题质量,针对油田业务试题专业性及逻辑性强、包含字母和数字等的特点,且现存的相似度计算方法不能很好地挖掘其深层语义信息,论文提出了一种基于Siamese网络的油田业务试题相似度计算方法,首先利用双向长短期记忆网络提取试题的全局特征,之后通过注意力机制进一步突出试题的关键信息,之后采用1D-CNN将上述提取的试题信息与字嵌入信息进行融合拼接,以获得试题的深层次语义特征信息。最后,通过余弦相似度计算方法计算出两试题的语义相似度。论文方法在实际油田业务试题上的准确率、召回率以及F1值分别为91.29%、89.57%、90.99%。实验结果表明该方法的有效性。 展开更多
关键词 Siamese网络 油田业务试题相似度 BiLSTM 注意力机制 1D-CNN
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缬沙坦中亚硝胺药物成分相关杂质(Q)SAR评价及Ames试验研究
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作者 蒙宏 桑晶 +3 位作者 朱国荣 孙叶丹 王焌 匡荣 《中国现代应用药学》 北大核心 2025年第17期3081-3087,共7页
目的 结合基因毒性软件预测和细菌回复突变试验(Ames试验)评价缬沙坦中亚硝胺药物成分相关杂质(nitrosamine drug substance-related impurities,NDSRI)V6-NO的基因突变风险。方法 采用CASE Ultra软件对V6-NO进行初步预测和分类,采用标... 目的 结合基因毒性软件预测和细菌回复突变试验(Ames试验)评价缬沙坦中亚硝胺药物成分相关杂质(nitrosamine drug substance-related impurities,NDSRI)V6-NO的基因突变风险。方法 采用CASE Ultra软件对V6-NO进行初步预测和分类,采用标准平板掺入法Ames试验(±S9:10%大鼠肝S9混合液)和预培养法Mini-Ames试验(±S9:30%大鼠肝S9混合液,37℃预培养1 h)评价V6-NO的致突变性。结果 因V6-NO具有N-亚硝基类警示结构,基于统计学规则模型和专家知识规则模型的预测结果均为阳性,ICH M7分类为第3类,但基于统计学规则的预测结果显示该杂质结构中具有6个失活特征。Ames试验结果显示,在±S9条件下,在标准平板掺入法Ames试验中,V6-NO在每皿62~5 000μg剂量下回复突变菌落数均未超过溶媒对照组的2倍,在预培养法Mini-Ames试验中,V6-NO在每孔62.5~1 000μg剂量下回复突变菌落数也未超过溶媒对照组的2倍,Ames试验和Mini-Ames试验结果均为致突变阴性。结论 当NDSRI的软件预测结果为阳性,且与Ames试验结果不一致时,要综合分析和进一步的验证,主要从其结构中存在的活化和失活特征入手,并通过改进Ames试验条件进行验证,全面分析和了解NDSRI的致突变性风险,为药物研发提供有价值的参考信息。 展开更多
关键词 缬沙坦 亚硝胺药物成分相关杂质(NDSRI) (定量)构效关系 致突变性 ames试验 失活特征
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Advances and challenges in gastric cancer testing:the role of biomarkers 被引量:1
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作者 Yu Sun Pavitratha Puspanathan +1 位作者 Tony Lim Dongmei Lin 《Cancer Biology & Medicine》 2025年第3期212-230,共19页
Advances in the identification of molecular biomarkers and the development of targeted therapies have enhanced the prognosis of patients with advanced gastric cancer.Several established biomarkers have been widely int... Advances in the identification of molecular biomarkers and the development of targeted therapies have enhanced the prognosis of patients with advanced gastric cancer.Several established biomarkers have been widely integrated into routine clinical diagnostics of gastric cancer to guide personalized treatment.Human epidermal growth factor receptor 2(HER2)was the first molecular biomarker to be used in gastric cancer with trastuzumab being the first approved targeted therapy for HER2-positive gastric cancer.Programmed death-ligand 1 positivity and microsatellite instability can guide the use of immunotherapies,such as pembrolizumab and nivolumab.More recently,zolbetuximab has been approved for patients with claudin 18.2-positive diseases in some countries.More targeted therapies,including savolitinib for MET-positive patients,are currently under clinical investigation.However,the clinical application of these diagnostic approaches could be hampered by many existing challenges,including invasive and costly sampling methods,variability in immunohistochemistry interpretation,high costs and long turnaround times for next-generation sequencing,the absence of standardized and clinically validated diagnostic cut-off values for some biomarkers,and tumor heterogeneity.Novel testing and analysis techniques,such as artificial intelligence-assisted image analysis and multiplex immunohistochemistry,and emerging therapeutic strategies,including combination therapies that integrate immune checkpoint inhibitors with targeted therapies,offer potential solutions to some of these challenges.This article reviews recent progress in gastric cancer testing,outlines current challenges,and explores future directions for biomarker testing and targeted therapy for gastric cancer. 展开更多
关键词 Gastric cancer testING DIAGNOSIS biomarkers precision therapy
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