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一类4维3-李代数上的O-算子及导出的3-Pre-李代数
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作者 程紫莹 吕家凤 亢闯闯 《浙江师范大学学报(自然科学版)》 CAS 2025年第1期21-29,共9页
李代数的Operad理论应用于3-李代数,可自然地构造出3-Pre-李代数,其与Pre-李代数有很多相似的性质.利用4维复3-李代数的分类以及3-李代数和O-算子的结构常数的关系,使用Maple软件求解三次非线性方程组,对一类4维复3-李代数上与伴随表示... 李代数的Operad理论应用于3-李代数,可自然地构造出3-Pre-李代数,其与Pre-李代数有很多相似的性质.利用4维复3-李代数的分类以及3-李代数和O-算子的结构常数的关系,使用Maple软件求解三次非线性方程组,对一类4维复3-李代数上与伴随表示相结合的O-算子进行了刻画.此外,利用所得结果,给出了这些O-算子导出的26个3-Pre-李代数的例子. 展开更多
关键词 3-pre-李代数 O-算子 3-李代数 pre-李代数
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天津市部分新诊断HIV阳性男男性行为者PrEP和nPEP知晓及使用情况分析 被引量:1
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作者 费丽萍 赵鹤鹤 +6 位作者 王实 郭燕 龚卉 于茂河 杨杰 汤后林 吕繁 《中国艾滋病性病》 北大核心 2025年第3期283-287,共5页
目的了解新诊断HIV阳性MSM对PrEP和nPEP的知晓和使用情况。方法以2023年12月至2024年8月天津市部分新诊断HIV阳性MSM为研究对象,通过问卷调查收集研究对象的基本人口学信息、性行为特征及PrEP、nPEP的知晓和使用情况。使用Logistic回归... 目的了解新诊断HIV阳性MSM对PrEP和nPEP的知晓和使用情况。方法以2023年12月至2024年8月天津市部分新诊断HIV阳性MSM为研究对象,通过问卷调查收集研究对象的基本人口学信息、性行为特征及PrEP、nPEP的知晓和使用情况。使用Logistic回归分析新诊断HIV阳性MSM中PrEP和nPEP知晓的影响因素。结果共计纳入研究对象251人,其中83人(33.1%)知晓PrEP,111人(55.8%)知晓nPEP。12人(4.8%)曾使用过PrEP,9人(3.6%)曾使用过nPEP。多因素Logistic回归分析显示,大专及以上文化程度者(PrEP:aOR=3.31,95%CI:1.66~6.83;nPEP:aOR=2.33,95%CI:1.28~4.28)、性伴数≥2(PrEP:aOR=2.29,95%CI:1.14~4.69;nPEP:aOR=2.02,95%CI:1.12~3.68)、既往有HIV检测史(PrEP:aOR=12.26,95%CI:5.62~30.00;nPEP:aOR=3.99,95%CI:2.21~7.36)是PrEP和nPEP知晓的促进因素。此外,同性性向(aOR=2.52,95%CI:1.08~6.31)也是nPEP知晓的促进因素。结论天津市部分新诊断HIV阳性MSM的PrEP和nPEP的知晓和使用情况均较低。可以通过网络平台、社会组织及同伴教育者在动员MSM进行HIV检测的同时普及PrEP和nPEP知识。 展开更多
关键词 艾滋病病毒感染者 暴露前预防 非职业暴露后预防 知晓 男男性行为者
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大连市MSM对HIV PrEP用药知晓和使用意愿相关因素分析
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作者 张敏 孙明玉 +9 位作者 曹雪 赵志杰 熊帮洁 张群 王雅琪 洪晟杰 马兆煜 张宇 崔佳 李程 《中国艾滋病性病》 北大核心 2025年第9期997-1002,共6页
目的分析大连市MSM对HIV PrEP用药的知晓、使用意愿及相关因素,为制定该人群HIV PrEP服务策略提供科学依据。方法采用“滚雪球”的方法,通过MSM社会组织和疾控中心自愿咨询检测门诊招募MSM,进行面对面问卷调查,收集其一般人口学特征、... 目的分析大连市MSM对HIV PrEP用药的知晓、使用意愿及相关因素,为制定该人群HIV PrEP服务策略提供科学依据。方法采用“滚雪球”的方法,通过MSM社会组织和疾控中心自愿咨询检测门诊招募MSM,进行面对面问卷调查,收集其一般人口学特征、行为学信息、对PrEP的知晓和使用意愿情况,并以PrEP知晓和PrEP使用意愿为因变量,进行χ^(2)检验和多因素Logistic回归分析。结果共调查500名MSM,年龄18~77岁,PrEP知晓率46.0%,63.0%的调查对象知晓并愿意使用PrEP。多因素Logistic回归分析结果显示,最近3个月从未使用安全套(OR=3.839,95%CI:1.549~9.516),使用过rush popper(OR=2.546,95%CI:1.454~4.458),接受过HIV检测(OR=1.951,95%CI:1.039~3.662),知晓PEP(OR=23.678,95%CI:13.284~42.205)是PrEP知晓的促进因素,性行为方式为同性/异性均可(OR=0.568,95%CI:0.343~0.941)是PrEP知晓的阻碍因素。月收入≥5000元(OR=2.816,95%CI:1.190~6.664),性伴数量>10个(OR=2.338,95%CI:1.129~4.842),近3个月有时使用安全套(OR=2.667,95%CI:1.257~5.661),透露过性向(OR=2.728,95%CI:1.425~5.224),知晓PEP(OR=7.057,95%CI:1.661~29.977)是PrEP使用意愿的促进因素。结论大连市MSM的PrEP知晓和使用意愿比例较低,应进一步开展针对性PrEP宣传教育,尤其是提高不使用安全套、使用过rush、多性伴MSM对PrEP正确认识和引导有需求的MSM正确使用PrEP,从而提升PrEP知晓和使用。 展开更多
关键词 艾滋病病毒 男男性行为者 暴露前预防 影响因素
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RPC-Chain:基于信誉机制与受控PRE的众包模型链
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作者 董文浩 朱晓军 +1 位作者 王龙 杨倩倩 《计算机应用研究》 北大核心 2025年第1期36-41,共6页
为解决众包面临的信任问题、不对称贡献与收益关系以及数据安全性共享等挑战,提出一种基于信誉模型与受控代理重加密(PRE)的众包模型链,即RPC-Chain。RPC-Chain基于超级账本Fabric,将众包模型的交易流程抽象化。首先,完善信誉机制提高... 为解决众包面临的信任问题、不对称贡献与收益关系以及数据安全性共享等挑战,提出一种基于信誉模型与受控代理重加密(PRE)的众包模型链,即RPC-Chain。RPC-Chain基于超级账本Fabric,将众包模型的交易流程抽象化。首先,完善信誉机制提高系统整体的效率与公平;其次,引入受控代理重加密以确保数据安全共享服务;最后,使用Fabric搭建众包区块链仿真平台并进行了相关测试。实验表明,该方案在模型设计、数据安全加密共享和信誉模型的激励效果等方面显示出一定优势。 展开更多
关键词 区块链 代理重加密 信誉机制 智能合约 众包
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Pseudoephedrine: A Review and Benefit-Risk Assessment with Reference to the Risk of Posterior Reversible Encephalopathy Syndrome (PRES) and Reversible Cerebral Vasoconstriction Syndrome (RCVS)
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作者 Ronald Eccles 《Open Journal of Respiratory Diseases》 2025年第1期19-34,共16页
Pseudoephedrine (PSE) is a widely used nasal decongestant. A review by the European Medicines Agency has reported that PSE may be associated with risks of posterior reversible encephalopathy syndrome (PRES) and revers... Pseudoephedrine (PSE) is a widely used nasal decongestant. A review by the European Medicines Agency has reported that PSE may be associated with risks of posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS). PRES and RCVS are rare but serious conditions that affect cerebral blood flow. This review discusses the pharmacology of PSE and potential risks for PRES and RCVS and concludes that considering the common use of PSE, with over 70 million packs of PSE taken each year in the European Union and the United Kingdom, and the rare occurrence of PRES and RCVS, that the risks of developing PRES/RCVS on exposure to PSE are likely to be very low. 展开更多
关键词 Posterior Reversible Encephalopathy Syndrome (preS) Reversible Cerebral Vasoconstriction Syndrome (RCVS) PSEUDOEPHEDRINE European Medicines Agency
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High Speed Regular Expression Matching Engine with Fast Pre-Processing 被引量:1
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作者 Zhe Fu Jun Li 《China Communications》 SCIE CSCD 2019年第2期177-188,共12页
Regular expression matching is playing an important role in deep inspection. The rapid development of SDN and NFV makes the network more dynamic, bringing serious challenges to traditional deep inspection matching eng... Regular expression matching is playing an important role in deep inspection. The rapid development of SDN and NFV makes the network more dynamic, bringing serious challenges to traditional deep inspection matching engines. However, state-of-theart matching methods often require a significant amount of pre-processing time and hence are not suitable for this fast updating scenario. In this paper, a novel matching engine called BFA is proposed to achieve high-speed regular expression matching with fast pre-processing. Experiments demonstrate that BFA obtains 5 to 20 times more update abilities compared to existing regular expression matching methods, and scales well on multi-core platforms. 展开更多
关键词 deep inspection FINITE AUTOMATON REGULAR expression MATCHING pre-processing
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新疆MSM基于事件驱动型PrEP用药方案的成本效用分析
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作者 王骋昊 杨恒 +1 位作者 边举元 张国珍 《中国艾滋病性病》 北大核心 2025年第7期737-743,共7页
目的 评估在新疆高危MSM中基于事件驱动型PrEP用药方案,实施暴露前预防用药策略的成本效用。方法 基于事件驱动型PrEP用药方案,依据高危MSM的不同占比、PrEP覆盖率和依从性设立8种干预策略,利用Markov模型,计算无PrEP干预和不同PrEP干... 目的 评估在新疆高危MSM中基于事件驱动型PrEP用药方案,实施暴露前预防用药策略的成本效用。方法 基于事件驱动型PrEP用药方案,依据高危MSM的不同占比、PrEP覆盖率和依从性设立8种干预策略,利用Markov模型,计算无PrEP干预和不同PrEP干预策略的成本和质量调整寿命年,以2022年新疆全年人均国内生产总值为标准评价PrEP策略的经济价值。结果 在中依从性且高危MSM占比为20%或40%,覆盖率分别为50%、80%时,成本效用比分别比为19 687元/QALY、19 676元/QALY、19 671元/QALY、19 672元/QALY;在高依从性高危MSM占比为20%或40%、覆盖率分别为50%、80%时,成本效用比分别为18 848元/QALY、18 857元/QALY,18 858元/QALY、18 855元/QALY,均小于2022年新疆人均GDP。结论 在高危MSM中基于事件驱动型PrEP用药方案实施PrEP策略有较好经济效益。未来应多渠道,针对性宣传PrEP;探索低成本PrEP方案;通过同伴监督等方式强化PrEP的依从性。 展开更多
关键词 艾滋病 暴露前预防用药 男男性行为者 MARKOV模型 成本效用分析
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Wheat TaPKL genes regulate pre-harvest sprouting and yield-related traits
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作者 Wanqing Bai Ziyi Yang +5 位作者 Xuchang Yu Shuxian Huang Yufan Wang Yexing Jing Yunwei Zhang Jiaqiang Sun 《Journal of Genetics and Genomics》 2025年第9期1148-1150,共3页
Wheat(Triticum aestivum L.)is an important staple food crop in the world and supplies about 20%of human caloric and protein consumption(Giraldo et al.,2019;Xiao et al.,2022).Wheat production accounts for~30%of global ... Wheat(Triticum aestivum L.)is an important staple food crop in the world and supplies about 20%of human caloric and protein consumption(Giraldo et al.,2019;Xiao et al.,2022).Wheat production accounts for~30%of global cereal crops(Li et al.,2019).With the global population increasing and the frequency of natural disasters rising,enhancing wheat yield is crucial to meet food demand.Spike traits such as increased grain number per spike are key determinants of wheat yield.Pre-harvest sprouting(PHS)is a significant natural disaster that severely impacts grain yield and end-use quality of wheat(Tai et al.,2021,2024). 展开更多
关键词 spike traits pre harvest sprouting yield GENES natural disasters WHEAT
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Empowering Sentiment Analysis in Resource-Constrained Environments:Leveraging Lightweight Pre-trained Models for Optimal Performance
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作者 V.Prema V.Elavazhahan 《Journal of Harbin Institute of Technology(New Series)》 2025年第1期76-84,共9页
Sentiment analysis,a cornerstone of natural language processing,has witnessed remarkable advancements driven by deep learning models which demonstrated impressive accuracy in discerning sentiment from text across vari... Sentiment analysis,a cornerstone of natural language processing,has witnessed remarkable advancements driven by deep learning models which demonstrated impressive accuracy in discerning sentiment from text across various domains.However,the deployment of such models in resource-constrained environments presents a unique set of challenges that require innovative solutions.Resource-constrained environments encompass scenarios where computing resources,memory,and energy availability are restricted.To empower sentiment analysis in resource-constrained environments,we address the crucial need by leveraging lightweight pre-trained models.These models,derived from popular architectures such as DistilBERT,MobileBERT,ALBERT,TinyBERT,ELECTRA,and SqueezeBERT,offer a promising solution to the resource limitations imposed by these environments.By distilling the knowledge from larger models into smaller ones and employing various optimization techniques,these lightweight models aim to strike a balance between performance and resource efficiency.This paper endeavors to explore the performance of multiple lightweight pre-trained models in sentiment analysis tasks specific to such environments and provide insights into their viability for practical deployment. 展开更多
关键词 sentiment analysis light weight models resource⁃constrained environment pre⁃trained models
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Amaurosis fugax in primigravida woman precursor of posterior reverse encephalopathy syndrome concurrent with macular edema
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作者 Panayiotis Christodoulou Ioannis Katsimpris 《International Journal of Ophthalmology(English edition)》 2025年第11期2213-2216,共4页
Dear Editor,Posterior reverse encephalopathy syndrome(PRES),manifests as a confusional state/delirium,convulsion,or acute blindness which illustrates in magnetic resonance imaging(MRI)typical bilateral white matter le... Dear Editor,Posterior reverse encephalopathy syndrome(PRES),manifests as a confusional state/delirium,convulsion,or acute blindness which illustrates in magnetic resonance imaging(MRI)typical bilateral white matter lesions.These clinical and radiological changes are reversible in two to three weeks,usually generated by acute hypertension,preeclampsia,eclampsia,immunosuppression,septicemia,and end-stage renal disease.PRES is commonly diagnosed in patients in their thirties. 展开更多
关键词 posterior reversible encephalopathy syndrome amaurosis fugax PRIMIGRAVIDA macular edema reverse encephalopathy syndrome pres manifests clinical radiological changes
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乙型肝炎病毒preS基因突变对乙型肝炎病毒相关肝细胞癌的诊断价值
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作者 陈秋宇 程倬 +2 位作者 邬亚鑫 邓立功 庞红全 《传染病信息》 2025年第4期313-319,共7页
目的分析乙型肝炎病毒相关肝细胞癌(hepatocellular carcinoma,HCC)患者的乙型肝炎病毒(hepatitis B virus,HBV)前表面抗原(preS)基因突变特点,描述HBV preS基因突变对HBV相关HCC的诊断价值。方法回顾性分析2019年9月至2023年9月就诊于... 目的分析乙型肝炎病毒相关肝细胞癌(hepatocellular carcinoma,HCC)患者的乙型肝炎病毒(hepatitis B virus,HBV)前表面抗原(preS)基因突变特点,描述HBV preS基因突变对HBV相关HCC的诊断价值。方法回顾性分析2019年9月至2023年9月就诊于达州市中心医院消化内科的慢性乙型肝炎(chronic hepatitis B,CHB)患者(CHB组)和HBV相关HCC患者(HCC组)。采用sanger测序法分析preS区突变。结果HCC组的患者年龄更大、基因型为C型的患者更多、HBV DNA水平更低、甲胎蛋白(alpha fetoprotein,AFP)水平更高(P<0.05)。在HCC组及CHB组中,共有24.41%(31/127)的患者发生preS1缺失,preS1区共发现47.90%(57/119)的点突变;共有16.54%(21/127)的患者发生preS2缺失,preS2区共发现65.45%(36/55)的点突变。preS1区W4P/R/Y、D27G/S、N51Y/T/S/Q/P、I/N56H/W、K57Q/K、A60V、D/A62S/T、G73S/N、A90T/S/G、V95A和L108V/I,以及preS2区T125S/N/P、F141V/L/I、V158A点突变在HCC组中的发生率高于CHB组(P<0.05)。基因型为C型、HBV DNA以及W4P/R/Y(preS1)、A90T/S/G(preS1)、L108V/I(preS1)、F141V/L/I(preS2)点突变可独立诊断CHB患者中HCC的发生。结论preS区W4P/R/Y(preS1)、A90T/S/G(preS1)、L108V/I(preS1)、F141V/L/I(preS2)与HCC发生相关,使用这些点突变检测将有助于HBV相关HCC的临床诊断。 展开更多
关键词 肝细胞癌 乙型肝炎病毒 乙型肝炎病毒前表面抗原 基因突变 诊断
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Commentary on the dose-response effect of pre-exercise carbohydrates in McArdle disease:Methodological considerations and practical implications
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作者 Jiawei Du Jinghua Hou 《Journal of Sport and Health Science》 2025年第2期77-78,共2页
We read with great interest the recent article by Valenzuela et al.1titled“Dose-response effect of pre-exercise carbohydrates under muscle glycogen unavailability:Insights from McArdle disease”published in the Journ... We read with great interest the recent article by Valenzuela et al.1titled“Dose-response effect of pre-exercise carbohydrates under muscle glycogen unavailability:Insights from McArdle disease”published in the Journal of Sport and Health Science The study's exploration of the effects of varying carbohydrate(CHO)doses on exercise capacity in Mc Ardle disease,a condition characterized by complete muscle glycogen unavailability,is a significant contribution to the field of sports science and metabolic disorders. 展开更多
关键词 dose response exercise capacity mcardle disease published muscle glycogen sports science metabolic disorders McArdle disease pre exercise carbohydrates
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Scientific data products and the data pre-processing subsystem of the Chang'e-3 mission 被引量:1
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作者 Xu Tan Jian-Jun Liu +7 位作者 Chun-Lai Li Jian-Qing Feng Xin Ren Fen-Fei Wang Wei Yan Wei Zuo Xiao-Qian Wang Zhou-Bin Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1682-1694,共13页
The Chang'e-3 (CE-3) mission is China's first exploration mission on the surface of the Moon that uses a lander and a rover. Eight instruments that form the scientific payloads have the following objectives: (1... The Chang'e-3 (CE-3) mission is China's first exploration mission on the surface of the Moon that uses a lander and a rover. Eight instruments that form the scientific payloads have the following objectives: (1) investigate the morphological features and geological structures at the landing site; (2) integrated in-situ analysis of minerals and chemical compositions; (3) integrated exploration of the structure of the lunar interior; (4) exploration of the lunar-terrestrial space environment, lunar sur- face environment and acquire Moon-based ultraviolet astronomical observations. The Ground Research and Application System (GRAS) is in charge of data acquisition and pre-processing, management of the payload in orbit, and managing the data products and their applications. The Data Pre-processing Subsystem (DPS) is a part of GRAS. The task of DPS is the pre-processing of raw data from the eight instruments that are part of CE-3, including channel processing, unpacking, package sorting, calibration and correction, identification of geographical location, calculation of probe azimuth angle, probe zenith angle, solar azimuth angle, and solar zenith angle and so on, and conducting quality checks. These processes produce Level 0, Level 1 and Level 2 data. The computing platform of this subsystem is comprised of a high-performance computing cluster, including a real-time subsystem used for processing Level 0 data and a post-time subsystem for generating Level 1 and Level 2 data. This paper de- scribes the CE-3 data pre-processing method, the data pre-processing subsystem, data classification, data validity and data products that are used for scientific studies. 展开更多
关键词 Moon: data products -- methods: data pre-processing -- space vehicles:instruments
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男男性行为者PrEP污名化体验的Meta整合
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作者 彭雨馨 钟涛 +1 位作者 徐璇 付光蕾 《中国艾滋病性病》 北大核心 2025年第1期106-111,共6页
目的系统评价和整合MSM暴露前预防污名化体验的质性研究,为MSM实施针对性干预提供循证依据。方法检索Cochrane Library、PubMed、Embase、Web of Science、CINAHL、SinoMed、万方数据库、中国知网和维普数据库中关于MSM暴露前预防污名... 目的系统评价和整合MSM暴露前预防污名化体验的质性研究,为MSM实施针对性干预提供循证依据。方法检索Cochrane Library、PubMed、Embase、Web of Science、CINAHL、SinoMed、万方数据库、中国知网和维普数据库中关于MSM暴露前预防污名化体验的质性研究,检索时限为建库至2024年9月。结果共纳入16篇基于国外研究的文献,提炼出57个研究结果,形成14个新类别,进一步归纳得到4个整合结果:污名化影响因素复杂、污名化存在多重表现、污名化影响日常生活、污名化应对策略多样。结论MSM暴露前预防污名化体验复杂,未来可借鉴国外研究,结合我国国情及文化背景,加强医护人员专业化培训,运用数字化工具积极实施综合性干预措施,联合家庭、社区构建整体化社会支持模式,帮助MSM减轻污名化体验。 展开更多
关键词 HIV 男男性行为者 暴露前预防 污名化 质性研究 Meta整合
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Pre-processing filter design at transmitters for IBI mitigation in an OFDM system 被引量:1
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作者 Xia Wang Lei Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第5期722-728,共7页
In order to meet the demands for high transmission rates and high service quality in broadband wireless communication systems, orthogonal frequency division multiplexing (OFDM) has been adopted in some standards. Ho... In order to meet the demands for high transmission rates and high service quality in broadband wireless communication systems, orthogonal frequency division multiplexing (OFDM) has been adopted in some standards. However, the inter-block interference (IBI) and inter-carrier interference (ICI) in an OFDM system affect the performance. To mitigate IBI and ICI, some pre-processing approaches have been proposed based on full channel state information (CSI), which improved the system performance. A pre-processing filter based on partial CSI at the transmitter is designed and investigated. The filter coefficient is given by the optimization processing, the symbol error rate (SER) is tested, and the computation complexity of the proposed scheme is analyzed. Computer simulation results show that the proposed pre-processing filter can effectively mitigate IBI and ICI and the performance can be improved. Compared with pre-processing approaches at the transmitter based on full CSI, the proposed scheme has high spectral efficiency, limited CSI feedback and low computation complexity. 展开更多
关键词 pre-processing filter inter-block interference (IBI) mitigation limited feedback orthogonal frequency division multiplexing (OFDM).
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Research of Image pre-processing Algorithm in Automation Fingerprint Identification
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作者 Jiang,Jie Li, Jie Hu, Xiaoli 《微计算机信息》 北大核心 2005年第12X期172-174,共3页
In the paper, a valid method of fingerprint Image pre- processing is introduced. Experiment results show that this kind of algorithm can availably wipe off yawp imported by the incom- plete leave fingerprint - marking... In the paper, a valid method of fingerprint Image pre- processing is introduced. Experiment results show that this kind of algorithm can availably wipe off yawp imported by the incom- plete leave fingerprint - marking of sensor surface when finger- print sensor record fingerprint. Meanwhile, it can extract the ef- fective and uneffective zone of fingerprint effectively, and also further enhance ridge line and vale line of fingerprint so that make the lines of fingerprint clear, continuum, lubricity and has better contrast, at the same time, has quite quick speed, this fingerprint Image pre- processing time can be shorten greatly. 展开更多
关键词 指纹识别 图象处理 图象分割 传感器
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原核生物pre-tRNA 5'末端剪切酶的结构和功能研究
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作者 邵齐源 李洋洋 +1 位作者 张威振 甘建华 《复旦学报(自然科学版)》 北大核心 2025年第1期113-120,共8页
5'末端的剪切是pre-tRNA加工和成熟过程中非常重要的一个环节,由RNase P负责催化。不同于常规的RNase P,原核生物中存在一类protein-only RNase P(也称HARP),不需要依赖核酶就能对pre-tRNA的5'末端进行剪切。为了阐明HARP结合... 5'末端的剪切是pre-tRNA加工和成熟过程中非常重要的一个环节,由RNase P负责催化。不同于常规的RNase P,原核生物中存在一类protein-only RNase P(也称HARP),不需要依赖核酶就能对pre-tRNA的5'末端进行剪切。为了阐明HARP结合和剪切pre-tRNA的分子机制,我们表达和纯化了Thermocrinis ruber来源的HARP蛋白(TrHARP)。定点突变、分子筛和体外活性实验证实TrHARP具有pre-tRNA剪切活性,而且该活性受到蛋白聚合状态的影响。此外,我们还筛选获得了TrHARP蛋白质的晶体,采集了衍射数据并建立了初始的结构模型。尽管TrHARP与Aquifex aeolicus来源的HARP Aq_880的折叠方式类似,但TrHARP与Aq_880在结构中的聚合方式和相对方位存在显著的差异。分子筛以及负染电镜实验结果均显示pre-tRNA的引入会导致HARP结构的解聚,这为进一步阐明HARP结合和催化pre-tRNA的5'末端成熟的分子机制奠定了基础。 展开更多
关键词 protein-only RNase P pre-tRNA HARP 晶体结构 功能 蛋白表达
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HIV/梅毒双重检测在MSM PrEP使用者中的成本效果分析
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作者 张忻恒 高天帅 +1 位作者 赖锦 陈丹镝 《中国艾滋病性病》 北大核心 2025年第9期980-986,共7页
目的评估在使用PrEP的MSM中进行单独和双重HIV/梅毒检测的成本效果,为推动双重检测在MSM中的扩大应用提供决策依据。方法本研究采用马尔可夫模型,模拟2020年至2024年中国MSM中HIV和梅毒的流行情况,并假设了一个由10万名年龄≥18岁的MSM... 目的评估在使用PrEP的MSM中进行单独和双重HIV/梅毒检测的成本效果,为推动双重检测在MSM中的扩大应用提供决策依据。方法本研究采用马尔可夫模型,模拟2020年至2024年中国MSM中HIV和梅毒的流行情况,并假设了一个由10万名年龄≥18岁的MSM组成的静态队列,效果指标采用质量调整寿命年(QALYs)。结果实施背景频率的单独梅毒检测(年检测率60.4%)、每3个月进行一次单独梅毒检测和每3个月进行一次HIV/梅毒双重检测将分别额外花费1400万美元、2160万美元和1600万美元,其增量成本效果比(ICER)分别为5457美元/QALY、3826美元/QALY和5174美元/QALY。结论在使用PrEP的MSM中每3个月进行一次HIV/梅毒双重检测比单独检测更具成本效果。双重检测不仅降低了检测成本,还减少了个人需要接受检测的次数,有望提高检测依从性。 展开更多
关键词 艾滋病病毒 梅毒 双重检测 暴露前预防 男男性行为者 成本效果分析
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The Role of Combined OSR and SDF Method for Pre-Processing of Microarray Data that Accounts for Effective Denoising and Quantification
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作者 Jayakishan Meher Mukesh Kumar Raval +1 位作者 Pramod Kumar Meher Gananath Dash 《Journal of Signal and Information Processing》 2011年第3期190-195,共6页
Microarray data is inherently noisy due to the noise contaminated from various sources during the preparation of microarray slide and thus it greatly affects the accuracy of the gene expression. How to eliminate the e... Microarray data is inherently noisy due to the noise contaminated from various sources during the preparation of microarray slide and thus it greatly affects the accuracy of the gene expression. How to eliminate the effect of the noise constitutes a challenging problem in microarray analysis. Efficient denoising is often a necessary and the first step to be taken before the image data is analyzed to compensate for data corruption and for effective utilization for these data. Hence preprocessing of microarray image is an essential to eliminate the background noise in order to enhance the image quality and effective quantification. Existing denoising techniques based on transformed domain have been utilized for microarray noise reduction with their own limitations. The objective of this paper is to introduce novel preprocessing techniques such as optimized spatial resolution (OSR) and spatial domain filtering (SDF) for reduction of noise from microarray data and reduction of error during quantification process for estimating the microarray spots accurately to determine expression level of genes. Besides combined optimized spatial resolution and spatial filtering is proposed and found improved denoising of microarray data with effective quantification of spots. The proposed method has been validated in microarray images of gene expression profiles of Myeloid Leukemia using Stanford Microarray Database with various quality measures such as signal to noise ratio, peak signal to noise ratio, image fidelity, structural content, absolute average difference and correlation quality. It was observed by quantitative analysis that the proposed technique is more efficient for denoising the microarray image which enables to make it suitable for effective quantification. 展开更多
关键词 DENOISING MICROARRAY pre-processing Quantification SPATIAL Domain Filtering Optimized SPATIAL Resolution Quality Measures
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血清preS1水平与慢性乙型肝炎患者肝纤维化的关系及对癌变的诊断价值 被引量:4
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作者 高兴娟 程磊 +5 位作者 马秀清 刘守珠 王宝英 刘海燕 才德吉 杨兴唐 《传染病信息》 2024年第2期132-136,共5页
目的分析血清乙型肝炎病毒(hepatitis B virus,HBV)前S1蛋白(precursor S1 protein,preS1)与慢性乙型肝炎(chronic hepatitis B,CHB)肝纤维化及癌变进展的相关性。方法对2019年10月—2021年10月期间在青海红十字医院接受检查的228例乙... 目的分析血清乙型肝炎病毒(hepatitis B virus,HBV)前S1蛋白(precursor S1 protein,preS1)与慢性乙型肝炎(chronic hepatitis B,CHB)肝纤维化及癌变进展的相关性。方法对2019年10月—2021年10月期间在青海红十字医院接受检查的228例乙肝表面抗原(hepatitis B surface antigen,HBsAg)阳性慢性HBV感染者进行回顾性分析,其中CHB患者75例、肝硬化(liver cirrhosis,LC)患者93例(LC组)、肝细胞癌(hepatocellular carcinoma,HCC)患者60例(HCC组)。根据LC和HCC组肝组织活检分析肝脏炎症活动及肝纤维化程度。结果HCC组血清preS1水平[496.32(457.63,988.0)ng/mL]和LC组[338.72(247.93,554.61)ng/mL]血清preS1水平均显著高于CHB组[113.69(87.09,177.40)ng/mL],且差异具有统计学意义(P均<0.05)。HCC组血清preS1水平亦高于LC组(P=0.002)。经受试者工作特征曲线分析,血清preS1水平鉴别诊断CHB与LC的曲线下面积(area under the curve,AUC)是0.881(95%CI:0.830~0.932),鉴别诊断CHB/LC与HCC的AUC是0.861(95%CI:0.815~0.908)。3组患者的血清preS1水平与HBsAg(rs=0.799,P<0.001)呈强正相关和Log HBV DNA(rs=0.262,P<0.001)呈弱正相关。此外LC组和HCC组血清preS1水平与肝脏炎症活动分级(rs=0.201,P=0.009)及肝纤维化分期也呈弱正相关性(rs=0.295,P<0.001)。结论血清preS1水平与血清HBsAg、HBV DNA水平和肝脏炎症和纤维化进展呈正相关,有可能成为鉴别诊断HBV相关慢性肝病肝硬化或癌变的候选标志物。 展开更多
关键词 乙型肝炎病毒 HBV前S1蛋白 慢性乙型肝炎 肝纤维化 肝硬化 肝细胞癌
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