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Revisiting blastocyst biopsy strategies in modern IVF practice:Lessons from Capalbo et al 2014 and 2016
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作者 Thinh Ngo Van Dung Le Thi Thuy +1 位作者 Nhung Dang Thi Huyen Trang Nguyen Ha 《Asian pacific Journal of Reproduction》 2025年第6期285-286,共2页
Trophectoderm(TE)biopsy has become the preferred approach in preimplantation genetic testing,providing clear advantages over polar body and cleavage-stage biopsy.However,the optimal timing and methodology for blastocy... Trophectoderm(TE)biopsy has become the preferred approach in preimplantation genetic testing,providing clear advantages over polar body and cleavage-stage biopsy.However,the optimal timing and methodology for blastocyst biopsy remain subjects of ongoing debate.McArthur et al in 2005 were the first to demonstrate the safety of TE biopsy at the hatching blastocyst stage with laser-assisted opening in the zona pellucida(ZP)on Day 3,reporting 100%survival of 1050 biopsied blastocysts,all of which re-expanded,with an implantation rate of 41%[1].Nearly a decade later,Capalbo et al in 2014 introduced a modified strategy,performing biopsy on fully expanded blastocysts by creating a laser-assisted ZP opening and immediately aspirating TE cells on Day 5. 展开更多
关键词 preimplantation genetic testingproviding blastocyst biopsy zona pellucida laser assisted zona puncture preimplantation genetic testing te biopsy trophectoderm biopsy hatching blastocyst stage
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Search for Dispersed Repeats in Oryza sativa Genome Using Iterative Procedure Method
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作者 Valentina RUDENKO Eugene KOROTKOV 《Rice science》 2025年第4期472-474,共3页
In this study,we searched for dispersed repeats(DRs)in the rice(Oryza sativa)genome using the iterative procedure(IP)method.The results revealed that the O.sativa genome contained 79 DR families,comprising 992739 DNA ... In this study,we searched for dispersed repeats(DRs)in the rice(Oryza sativa)genome using the iterative procedure(IP)method.The results revealed that the O.sativa genome contained 79 DR families,comprising 992739 DNA repeats,of which 496762 and 495977 were identified on the forward and reverse DNA strands,respectively.The detected DRs were,on average,374 bp in length and occupied 66.4%of the O.sativa genome.Totally 61%of DRs,identified by the IP method,overlapped with previously annotated dispersed repeats(ADRs)detected using the Extensive De Novo TE Annotator(EDTA)pipeline. 展开更多
关键词 Oryza sativa genome dna repeatsof iterative procedure annotated dispersed repeats dispersed repeats drs de novo te annotator dispersed repeats
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Evaluation of the Agronomic Performances of Eight Varieties of Orange-Fleshed Sweet Potato in Central Côte d’Ivoire
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作者 Konan Evrard Brice Dibi Niambet Jean-Michel Koffi +5 位作者 Adou Emmanuel Ehounou Brice Sidoine Essis Kouassi Thiègba Kouamé Kinampinan Adelphe Hala Adjo Christiane Koffi Guy Fernand Yao 《American Journal of Plant Sciences》 2025年第2期301-315,共15页
Sweet potato is one of the most important crops in Côte d’Ivoire. However, some constraints related to climate change limit its production. This study evaluated the agronomic and technological performances of ei... Sweet potato is one of the most important crops in Côte d’Ivoire. However, some constraints related to climate change limit its production. This study evaluated the agronomic and technological performances of eight varieties of orange-fleshed of sweet potato (Ipomoea batatas (L.) to identify the most promising ones. The results show three groups of varieties with different agronomic performances. Group 1 composed of Irene and Vita is characterized by low production of small and large tuberous roots, low number of productive plants and low yield. Group 2 consisting mainly of Kabode is characterized by high production and weight of large tuberous roots as well as high yield. Group 3, composed of Tacha-2 Ininda, Ejumula Gloria, TIB-440060, CIP-199062-1, Bela bela is characterized by high production of small and large tuberous roots, high number of productive plants and average yield. The TIB-440060 variety has a recovery rate of 100%. The Irene, Kabode, Vita, Kabode varieties were resistant to viral and fungal diseases. In terms of technological quality, the TIB-440060 and CIP-199062-1 varieties have the best organoleptic qualities. Given the agronomic performances of the Kabode, TIB-440060 and CIP-199062-1 varieties, could be selected as the elites varieties and distributed to producers. 展开更多
关键词 Sweet Potato Agronomic and technological Performances Climate Change te d’Ivoire
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Commentary on “A systematic review and meta-analysis comparing objectively measured and estimated fitness to predict all-cause and cardiovascular disease mortality in adults”
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作者 Barbara E.Ainsworth Zhenghua Cai 《Journal of Sport and Health Science》 2025年第3期128-130,共3页
Measuring cardiorespiratory fitness(CRF)is an important predictor of morbidity and mortality in epidemiological studies and clinical settings.1 However,the feasibility of measuring maximal CRF is low due to the time,e... Measuring cardiorespiratory fitness(CRF)is an important predictor of morbidity and mortality in epidemiological studies and clinical settings.1 However,the feasibility of measuring maximal CRF is low due to the time,equipment,and expertise needed to conduct laboratory cardiopulmonary exercise testing(CPET)to determine the maximal rate of oxygen uptake(VO2max)as an objective measure of CRF.Alternatively,indirect estimates of CRF have been applied by measuring maximal duration on treadmill or cycle ergometer tests,2,3 extrapolating maximal CRF from workload or heart rate during submaximal fitness tests,4,5 and using non-exercise algorithms to estimate CRF from an individual’s age,sex,body mass,and physical activity habits.6 It is assumed that objectively measured VO2max is superior to extrapolated and estimated values due to errors associated with the estimated values;7,8 however,until Singh et al.9 newly released article in the Journal of Sport and Health Science,the comparability of these methods in identifying risks for all-cause and cardiovascular disease(CVD)mortality was unknown. 展开更多
关键词 cardiorespiratory fitness measuring maximal duration treadmill cycle ergometer te all cause mortality meta analysis cardiopulmonary exercise testing cpet cardiorespiratory fitness crf systematic review
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Evaluation of Novel 3D Architectures Based on Knitting Technologies for Engineering Biological Tissues 被引量:1
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作者 RIBEIRO Viviana Pinto RIBEIRO Ana Soares +7 位作者 SILVA Carla Joana DURES Nelson Feio BONIFCIO Graa CORRELO Vitor Manuel MARQUES Alexandra Pinto SOUSA Rui Amandi OLIVEIRA Ana Leite REIS Rui Luís 《Journal of Donghua University(English Edition)》 EI CAS 2013年第5期421-426,共6页
Textile-based technologies are considered as potential routes for the production of 3D porous architectures for tissue engineering( TE) applications. We describe the use of two polymers,namely polybutylene succinate( ... Textile-based technologies are considered as potential routes for the production of 3D porous architectures for tissue engineering( TE) applications. We describe the use of two polymers,namely polybutylene succinate( PBS) and silk fibroin(SF) to produce fiber-based finely tuned porous architectures by weft and warp knittings. The obtained knitted constructs are described in terms of their morphology, mechanical properties,swelling ability,degradation behaviour,and cytotoxicity. Each type of polymer fibers allows for the processing of a very reproducible intra-architectural scaffold geometry,with distinct characteristics in terms of the surface physicochemistry,mechanical performance,and degradation capability,which has an impact on the resulting cell behaviour at the surface of the respective biotextiles. Preliminary cytotoxicity screening shows that both materials can support cell adhesion and proliferation. Furthermore, different surface modifications were performed( acid /alkaline treatment, UV radiation,and plasma) for modulating cell behavior. An increase of cell-material interactions were observed,indicating the important role of materials surface in the first hours of culturing. Human adipose-derived stem cells( hASCs) became an emerging possibility for regenerative medicine and tissue replacement therapies. The potential of the recently developed silk-based biotextile structures to promote hASCs adhesion,proliferation,and differentiation is also evaluated. The obtained results validate the developed constructs as viable matrices for TE applications. Given the processing efficacy and versatility of the knitting technology, and the interesting structural and surface properties of the proposed polymer fibers,it is foreseen that our developed systems can be attractive for the functional engineering of tissues such as bone,skin,ligaments or cartilage and also for develop more complex systems for further industrialization of TE products. 展开更多
关键词 textile-based teCHNOLOGIES silk POLYBUTYLENE succinate(PBS) surface modifications human adipose-derived stem cells(hASCs) tissue engineering(te)
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Molecular Identification of Maize Streak Virus in Côte d’Ivoire
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作者 Guinagui N’Doua Bertrand Koala Moustapha +6 位作者 Yéo Gnénakan Tuo Seydou Ouattara Bakary Ouattara Bognan Winnie Miyasi Sérémé Drissa Koné Daouda Fatogoma Sorho 《American Journal of Plant Sciences》 2025年第1期41-50,共10页
Maize (Zea mays L.) is the world’s leading cereal crop, with production estimated at over 1 billion tonnes in 2022. In Côte d’Ivoire, maize is one of the most widely consumed foods, with national production exc... Maize (Zea mays L.) is the world’s leading cereal crop, with production estimated at over 1 billion tonnes in 2022. In Côte d’Ivoire, maize is one of the most widely consumed foods, with national production exceeding 1 million tonnes in 2022. Despite its importance, this crop is subject to numerous biotic constraints, including Maize streak virus (MSV). The objective of this study was to characterize MSV isolates from Côte d’Ivoire using molecular biology techniques. To achieve this, maize leaf samples displaying characteristic symptoms of MSV were collected from different agro-ecological zones (AEZs) of Côte d’Ivoire. Total DNA was extracted from the collected samples using the CTAB method and quantified with a Nanodrop spectrophotometer. The C2 region of the MSV genome’s open reading frame (ORF) was amplified through polymerase chain reaction (PCR) using MSV-specific primers. The resulting PCR products were sequenced using the Sanger method. Bioinformatics analysis was performed using MSV sequences from other African countries (retrieved from NCBI) alongside sequences obtained in this study. The analysis was conducted using MEGA X version 10.05 software. The results showed that the main symptoms observed in the field included the presence of longitudinal light green streaks on leaves, stunted plant growth, and incomplete seed development in infected plants. Phylogenetic analysis of the sequences from Côte d’Ivoire revealed three monophyletic groups, with sequences of some isolates collected from the same plot belonging to different groups. The MSV sequences from Côte d’Ivoire are very close to those from Rwanda. This study underscores the need for further investigation into the genetic diversity of MSV strains to enhance the diagnosis and management of this viral disease, which is particularly prevalent in maize crops in Côte d’Ivoire. 展开更多
关键词 CHARACteRIZATION Molecular Biology MSV MAIZE te d’Ivoire
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High‑Performance p‑Type Bi_(2)Te_(3)‑Based Thermoelectric Materials with a Wide Temperature Range Obtained by Direct Sb Doping
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作者 Xicheng Guan Zhiyuan Liu +8 位作者 Ni Ma Zhou Li Juan Liu Huiyan Zhang Hailing Li Qian Ba Junjie Ma Chuangui Jin Ailin Xia 《Acta Metallurgica Sinica(English Letters)》 2025年第5期849-858,共10页
Doping modification is one of the most effective ways to optimize the thermoelectric properties of Bi_(2)Te_(3)-based alloys.P-type Bi_(2−x)Sb_(x)Te_(3) thermoelectric materials have been successfully prepared by dire... Doping modification is one of the most effective ways to optimize the thermoelectric properties of Bi_(2)Te_(3)-based alloys.P-type Bi_(2−x)Sb_(x)Te_(3) thermoelectric materials have been successfully prepared by direct Sb doping method.It can be found that doping Sb into Bi_(2)Te_(3) lattice array for Bi-site replacement facilitates the generation of Sb′Te anti-site defects.This anti-site defects can increase the hole concentration and optimize electrical transport properties of Bi_(2−x)Sb_(x)Te_(3) alloys.In addition,the point defects induced by mass and stress fluctuations and the Sb impurities produced during the sintering process can enhance the multi-scale phonon scattering and reduce the lattice thermal conductivity.As a result,the Bi_(0.47)Sb_(1.63)Te_(3) sample has a maximum thermoelectric figure of merit ZT of 1.04 at 350 K.It is worth noting that the bipolar effect of Bi_(2)Te_(3)-based alloys can be weakened with the increase of Sb content.The Bi_(0.44)Sb_(1.66)Te_(3) sample has a maximum average ZT value(0.93)in the temperature range of 300–500 K,indicating that direct doping of Sb can broaden the temperature range corresponding to the optimal ZT value.This work provides an idea for developing high-performance near room temperature thermoelectric materials with a wide temperature range. 展开更多
关键词 Bi2te3-based materials Sb doping Wide temperature range Thermoelectric properties
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A Comparative Study of the Technological Characteristics of Cotton Fibers from Two Types of Gins in Côte d’Ivoire
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作者 Brou Julien Kouakou Tièba Victor Ouattara +4 位作者 Koffi Christophe Kobenan Kouadio Emmanuel N’Goran Nogbou Ferdinand Amangoua Malanno Kouakou N’Guessan Maxime Kouame 《American Journal of Plant Sciences》 2025年第1期11-21,共11页
Production of this crop is experiencing significant challenges, resulting in a decline in seed and fiber quality. To address this challenge, generations of high-performance cotton plants of the Gossypium hirsutum L. s... Production of this crop is experiencing significant challenges, resulting in a decline in seed and fiber quality. To address this challenge, generations of high-performance cotton plants of the Gossypium hirsutum L. species have been developed and are currently being commercialized. This study evaluated the impact of gin types on the agro-industrial quality of cotton in Côte d’Ivoire. To this end, cotton from the G3, R1, and R2 generations was harvested, sampled, and ginned on machines with 10 and 170 saws in the localities of Ouangolodougou, Ferkessédougou, Korhogo, M’Bengué, Boundiali, Séguéla, and Mankono, as well as at the Centre National de Recherche Agronomique CNRA) in Bouaké. The results demonstrated that cotton fibers obtained from ginning on 10-saw machines exhibited superior quality compared to those from 170-saw machines. Fiber length, fiber length uniformity, and short fiber rate exhibited the highest deviations according to gin type. The use of 170-saw gins resulted in a notable decline in quality. Conversely, micronaire index, fiber tenacity and elongation, and reflectance remained consistent across machine types. These results will enable us to more effectively regulate and advise cotton-processing factories, which primarily utilize 170-saw gins to enhance agro-industrial quality in Côte d’Ivoire. Furthermore, these results will assist breeders in incorporating them into their processes to enhance the quality of the varieties they offer to farmers. 展开更多
关键词 Agro-Industrial Quality technological Characteristics Gossypium Hirsutum L. Saw Gin te d’Ivoire
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CdZnTe衬底对碲镉汞气相外延表面形貌的影响 被引量:1
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作者 王仍 焦翠灵 +6 位作者 张莉萍 张可锋 陆液 杜云辰 邵秀华 林杏潮 李向阳 《激光与红外》 CAS CSCD 北大核心 2015年第9期1064-1067,共4页
利用气相外延技术在Cd Zn Te衬底上生长Hg1-xCdxTe薄膜材料,通过在不同晶向、不同极性、不同晶向偏离角度Cd Zn Te衬底上的外延结果发现,Cd Zn Te衬底对外延形貌的影响非常大。(111)面衬底上外延形貌明显优于(211)面衬底的外延形貌。对... 利用气相外延技术在Cd Zn Te衬底上生长Hg1-xCdxTe薄膜材料,通过在不同晶向、不同极性、不同晶向偏离角度Cd Zn Te衬底上的外延结果发现,Cd Zn Te衬底对外延形貌的影响非常大。(111)面衬底上外延形貌明显优于(211)面衬底的外延形貌。对于同是<111>Cd Zn Te晶向的衬底,(111)Cd面Cd Zn Te衬底上的外延形貌明显优于(111)Te面。对于(111)Cd面Cd Zn Te衬底,当晶向偏离角度不同时,其外延形貌也有差异,晶向偏离角越小表面形貌越好。 展开更多
关键词 Hg1-xCdxte晶体 CdZnte衬底 (111)Cd面 (111)te
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碳效应增敏-电感耦合等离子体质谱法(ICP-MS)直接测定地球化学样品中的Te 被引量:1
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作者 袁秀雪 赵越 +3 位作者 江冶 乔爱香 胡萍 曹磊 《地质学刊》 2025年第1期103-110,共8页
采用HNO_(3)-HF-HClO4常压消解样品,优化前处理方法,考察标准(STD)模式和动能歧视(KED)模式下标准样品分析结果的准确度。分别添加体积分数为2%~30%的甲醇、乙醇、乙腈3种碳效应增敏剂并研究其对^(126)Te和^(128)Te信号强度及测定结果... 采用HNO_(3)-HF-HClO4常压消解样品,优化前处理方法,考察标准(STD)模式和动能歧视(KED)模式下标准样品分析结果的准确度。分别添加体积分数为2%~30%的甲醇、乙醇、乙腈3种碳效应增敏剂并研究其对^(126)Te和^(128)Te信号强度及测定结果准确度的影响,进而建立STD模式下电感耦合等离子体质谱法(ICP-MS)直接测定地球化学样品中碲(Te)的方法。结果表明,在STD和KED模式下^(126)Te、^(128)Te准确度几乎相同,在STD模式下添加体积分数为5%的乙醇增敏并以^(126)Te为分析同位素时,Te信号强度提高了1.39倍,方法检出限降为0.002 mg/kg。土壤、水系沉积物和岩石3类国家一级标准物质的测试结果表明,该方法简单方便、成本低,易于推广应用,适用于地球化学样品中Te的快速分析。 展开更多
关键词 碳效应增敏 te 乙醇 ICP-MS
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Radiation pattern analyses of circular aperture antenna to generate radio orbital angular momentum
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作者 LIN Cheng-long LIN Ming-tuan +1 位作者 LIU Pei-guo TANG Xing 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第6期1513-1523,共11页
Circular aperture antenna recently has been regarded as a nature source to generate high power radio orbital angular momentum (OAM) in millimeter (mm) wave; however, the radiation pattern was not investigated. Theoret... Circular aperture antenna recently has been regarded as a nature source to generate high power radio orbital angular momentum (OAM) in millimeter (mm) wave; however, the radiation pattern was not investigated. Theoretical derivation of radiation pattern of circular aperture OAM antenna is conducted to evaluate the performance. Extensive simulations verify the validity of the theoretical result. Furthermore, performance of such antenna excited by orthogonal TE and TM modes is compared, which shows the potential application for TEgl mode to create pure OAM g-1 mode in a practical system, providing guidance for generation of twisted radio waves in mm-wave bands. 展开更多
关键词 orbital angular momentum(OAM) twisted radio wave MILLIMEteR-WAVE circular aperture antenna radiation pattern te mode TM mode
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肥厚型梗阻性心肌病化学消融后急性期Tp-Te间期和Tp-Te/Q-T的变化 被引量:1
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作者 何玮 陈长曦 +4 位作者 孙丽卿 周浩 李晟 计光 黄伟剑 《心电与循环》 2015年第3期181-183,共3页
目的探讨肥厚型梗阻性心肌病(HOCM)化学消融后急性期Tp-Te间期和Tp-Te/Q-T的变化。方法 1 3例(男性3例,女性10例)HOCM患者行经皮酒精室间隔消融术治疗,分别于术前和术后行超声心动图和心电图检测。结果室间隔厚度和左心室质量指数消融... 目的探讨肥厚型梗阻性心肌病(HOCM)化学消融后急性期Tp-Te间期和Tp-Te/Q-T的变化。方法 1 3例(男性3例,女性10例)HOCM患者行经皮酒精室间隔消融术治疗,分别于术前和术后行超声心动图和心电图检测。结果室间隔厚度和左心室质量指数消融术后较术前明显降低[分别为(18.08±2.02)mm、(20.77±2.39)mm;(186.56±58.30)g/m^2、(208.79±72.76)g/m^2],差异均有统计学意义(均P<0.05)。Tp-Te间期、Tp-Te/Q-T和Tp-Te/Q-Tc在消融术后24h及3~5d较术前降低[Tp-Te间期术前(136.15±7.12)ms,术后24h(129.23±9.76)ms,术后3~5d(128.08±10.11)ms;Tp-Te/Q-T术前0.32±0.03,术后24h 0.29±0.03,术后3~5d 0.29±0.03;Tp-Te/Q-Tc术前0.30±0.03,术后24h 0.27±0.02,术后3~5d 0.27±0.03],差异均有统计学意义(均P<0.05)。结论 HOCM室间隔消融术后急性期Tp-Te间期、Tp-Te/Q-T和Tp-Te/Q-Tc明显缩短。 展开更多
关键词 肥厚型梗阻性心肌病 TP-te间期 Tp-te/Q-T Tp-te/Q-Tc 化学消融
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Cu_(2)Te基热电材料的制备及优化方法研究现状
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作者 李晔 王晓欢 夏阳阳 《热加工工艺》 北大核心 2025年第23期24-31,共8页
Cu_(2)Te作为热电材料具有输运性能可调、元素丰富、低毒性以及高温稳定性的优点。但是由于Te的电负性小,弱的电负性导致较弱和更少离子的Cu-X键,使得Cu_(2)Te的空穴浓度很高,ZT值较低,从而热电转化效率较低。利用不同的制备工艺并结合... Cu_(2)Te作为热电材料具有输运性能可调、元素丰富、低毒性以及高温稳定性的优点。但是由于Te的电负性小,弱的电负性导致较弱和更少离子的Cu-X键,使得Cu_(2)Te的空穴浓度很高,ZT值较低,从而热电转化效率较低。利用不同的制备工艺并结合元素掺杂、复合和控制元素含量等手段不断优化其电输运性能。总结了Cu_(2)Te的晶体结构、复杂的相变以及金属导电性,介绍了部分制备工艺和优化热电性能的方法。最后,总结了Cu_(2)Te基热电材料目前存在的问题及未来方向,为铜基热电材料的研究提供了借鉴价值。 展开更多
关键词 Cu_(2)te 热电材料 元素掺杂 复合
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一种宽带双脊TE21模耦合器的设计
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作者 张博 李振生 李栋 《河北省科学院学报》 2025年第3期15-19,共5页
针对传统TE21模耦合器工作带宽较窄,无法实现宽带跟踪的问题,本研究基于松紧耦合理论对TE21模耦合器的选模耦合方式进行了深入分析。同时利用双脊波导与常规矩形波导相比,在保持相同口径尺寸的前提下,双脊结构能够实现更低的截止频率和... 针对传统TE21模耦合器工作带宽较窄,无法实现宽带跟踪的问题,本研究基于松紧耦合理论对TE21模耦合器的选模耦合方式进行了深入分析。同时利用双脊波导与常规矩形波导相比,在保持相同口径尺寸的前提下,双脊结构能够实现更低的截止频率和更宽的高频工作带宽的独特优势,通过将耦合器副波导在宽边方向进行双脊加载优化设计,实现了主波导TE21模到每个副波导的高效耦合,耦合度达到-8.5 dB。最终研制的耦合器样机展现出优异的宽带特性,其最大耦合带宽达到1.8∶1,显著提升了器件性能。 展开更多
关键词 宽频带 te21模 定向耦合器 双脊波导
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一种S/X双频段同轴波导TE21模耦合器设计
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作者 张博 刘艳明 +1 位作者 王超 张连松 《无线互联科技》 2025年第14期107-110,115,共5页
文章提出了一种基于同轴波导的S/X双频段单脉冲自跟踪TE21模耦合器。X频段TE21模耦合器采用传输式,在25%的相对工作带宽内可实现-8.5 dB的单臂差模耦合度。S频段耦合器采用反射式,与传统的耦合器相比长度缩短了50%,在100 MHz的工作带宽... 文章提出了一种基于同轴波导的S/X双频段单脉冲自跟踪TE21模耦合器。X频段TE21模耦合器采用传输式,在25%的相对工作带宽内可实现-8.5 dB的单臂差模耦合度。S频段耦合器采用反射式,与传统的耦合器相比长度缩短了50%,在100 MHz的工作带宽内,耦合器对主模抑制度大于24 dB,差模单臂耦合度达到-7.1 dB。该耦合器性能优良可大大缩小TE21模自跟踪系统的结构尺寸。 展开更多
关键词 S/X双频段 单脉冲自跟踪 同轴波导 te21模
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同轴波导TE11模衰减和功率容量特性研究
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作者 焦一嵩 杜彪 《电波科学学报》 北大核心 2025年第3期596-602,共7页
针对双频/多频段同轴馈源对低损耗和高功率容量的需求,利用微扰法,基于同轴波导第一高次模TE11模的矢量模函数,导出了同轴TE11模的衰减常数与功率容量的计算公式。本文计算结果与商业软件HFSS仿真结果吻合较好,证明了本文方法和公式的... 针对双频/多频段同轴馈源对低损耗和高功率容量的需求,利用微扰法,基于同轴波导第一高次模TE11模的矢量模函数,导出了同轴TE11模的衰减常数与功率容量的计算公式。本文计算结果与商业软件HFSS仿真结果吻合较好,证明了本文方法和公式的正确性。同时,研究了同轴波导TE11模衰减常数和功率容量与同轴波导内外径比的关系。对于几种典型双频段共用的应用情况,基于损耗最小、功率容量最大和综合性能最优原则,分别给出了同轴馈源输入端内外径比初始参数的选取准则,为双频/多频段同轴馈源设计提供了理论支撑。 展开更多
关键词 同轴波导 te11模 衰减常数 功率容量 传输特性
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An Improved Description of Characteristics Length in Substrate Current Model for Submicron and Deep-Submicron LDD MOSFET's
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作者 于春利 杨林安 郝跃 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第9期1084-1090,共7页
A novel substrate current model is proposed for submicron and deep-submicron li ghtly-doped-drain (LDD) n-MOSFET,with the emphasis on accurate description of the characteristics length by taking the effects of channe... A novel substrate current model is proposed for submicron and deep-submicron li ghtly-doped-drain (LDD) n-MOSFET,with the emphasis on accurate description of the characteristics length by taking the effects of channel length and bias int o account.This is due to that the characteristics lenth significantly affects th e maximum lateral electric field and the length of velocity saturation region,bo th of which are very important in modeling the drain current and the substrate c urrent.The comparison between simulations and experiments shows a good predictio n of the model for submicron and deep-submicron LDD MOSFET.Moreover,the analyti cal model is suitable for descgn of devices as it is low in computation consumpt ion. 展开更多
关键词 LDD MOSFET substra te current characteristics length maximum lateral electric field
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大致正常心电图中Tp-Te间期预测冠状动脉重度狭窄的临床研究
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作者 杨艳丽 李颖 习诗良 《巴楚医学》 2025年第1期49-53,共5页
目的:通过分析大致正常心电图中T波峰末间期(Tp-Te间期)的变化,探讨Tp-Te间期是否可用于预测冠状动脉重度狭窄。方法:收集2020年1月—2024年5月在宜昌市中心人民医院行冠状动脉CT血管造影检查的患者663例,其中合并前降支重度狭窄(狭窄... 目的:通过分析大致正常心电图中T波峰末间期(Tp-Te间期)的变化,探讨Tp-Te间期是否可用于预测冠状动脉重度狭窄。方法:收集2020年1月—2024年5月在宜昌市中心人民医院行冠状动脉CT血管造影检查的患者663例,其中合并前降支重度狭窄(狭窄程度≥90%)的患者为病例组(n=146),完全无狭窄且无其它异常的患者为对照组(n=517)。收集两组患者的心电图记录,测量Tp-Te间期。采用Logistic回归模型绘制受试者工作特征(ROC)曲线,计算曲线下面积(AUC),绘制约登指数曲线,明确Tp-Te间期诊断冠状动脉重度狭窄的阈值、敏感性和特异性。结果:与对照组相比,病例组V1[(82.91±18.73)ms vs(72.31±15.22)ms]、V2[(90.48±16.86)ms vs(84.23±13.45)ms]、V3[(90.13±16.04)ms vs(83.11±14.79)ms]、V4[(88.86±15.03)ms vs(71.12±13.94)ms]的Tp-Te间期均明显升高(均P<0.001)。V1~V4的Tp-Te间期及联合预测的AUC值分别为0.691、0.582、0.573、0.714、0.633。当V4导联Tp-Te间期为79.5 ms时,预测的敏感性为74.66%,特异性为77.40%,为临床预测时的最佳平衡点52.06%。结论:Tp-Te间期可预测重度冠状动脉狭窄,V4导联效应量最大,预测效能最高,Tp-Te间期的阈值为79.5 ms。 展开更多
关键词 心电图 冠状动脉狭窄 TP-te间期
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基于LSTM-TE模型的冬枣可溶性固形物含量高光谱估测
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作者 刘傲然 孟惜 +3 位作者 刘智国 宋宇斐 赵雪曼 智丹宁 《光谱学与光谱分析》 北大核心 2025年第8期2326-2334,共9页
冬枣因其丰富的营养成分、香甜的口感和优良的风味,深受消费者的喜爱。随着消费者对水果品质要求的提高,可溶性固形物含量(SSC)作为衡量水果成熟度和口感质量的重要指标,已成为水果品质评估中的关键因素。因此,实现冬枣SSC的高效、无损... 冬枣因其丰富的营养成分、香甜的口感和优良的风味,深受消费者的喜爱。随着消费者对水果品质要求的提高,可溶性固形物含量(SSC)作为衡量水果成熟度和口感质量的重要指标,已成为水果品质评估中的关键因素。因此,实现冬枣SSC的高效、无损预测具有重要的应用价值和实际意义。提出一种融合长短时记忆网络(LSTM)与Transformer编码器的LSTM-TE模型,旨在实现冬枣SSC的快速无损预测。采集900个冬枣样本的高光谱数据并测定其SSC值,结合多种光谱数据预处理方法[包括多元散射校正(MSC)、矢量归一化(VN)、Savitzky-Golay(SG)滤波、一阶导数(D1)和二阶导数(D2)等]对数据进行处理,通过PLSR、SVR、VGG16、ResNet18、LSTM五种模型系统比较了10种预处理组合的效果,确定最优预处理方案为MSC-SG-D1。在该预处理方法的基础上,进一步构建了PLSR、SVR、VGG16、ResNet18、LSTM和LSTM-TE的多模型对比体系,并对其在测试集上的性能进行了对比分析。实验结果表明,LSTM-TE模型在测试集上的决定系数为0.9598,均方根误差为1.2690,较传统机器学习模型PLSR(R_(p)^(2)=0.8173)提升17.4%,较单一LSTM模型(R_(p)^(2)=0.8652)提升10.9%。该模型通过LSTM的时序特征捕捉能力与Transformer编码器的全局依赖建模优势,有效挖掘了高光谱数据中的非线性特征关系。本研究为冬枣品质的在线检测与分级提供了新的技术方案,对高光谱技术在精准农业中的应用具有重要参考价值。 展开更多
关键词 可溶性固形物含量(SSC) 高光谱 深度学习 LSTM-te模型
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Tp-Te预测ICD一级预防的有效性
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作者 黄启祥 黄清秀 +2 位作者 苏中州 张伟明 黄静瑜 《临床心电学杂志》 2020年第1期13-16,21,共5页
目的探讨Tp-Te/QRS和Tp-Te/(QT·QRS)在心脏性猝死(SCD)一级预防植入埋藏式心脏转复除颤器(ICD)有效性的预测价值。方法通过回顾性分析符合SCD一级预防并植入ICD患者的Tp-Te/QRS和Tp-Te/(QT·QRS)无创检测指标,并通过起搏器程... 目的探讨Tp-Te/QRS和Tp-Te/(QT·QRS)在心脏性猝死(SCD)一级预防植入埋藏式心脏转复除颤器(ICD)有效性的预测价值。方法通过回顾性分析符合SCD一级预防并植入ICD患者的Tp-Te/QRS和Tp-Te/(QT·QRS)无创检测指标,并通过起搏器程控仪调取起搏器数据,根据是否发生判断正确的心血管事件(室性心动过速或心室颤动)及适当的ICD治疗分两组,对比分析指标在两组间的统计差异程度。结果两组间Tp-Te/QRS和Tp-Te/(QT·QRS)有显著差异(p<0.01)。Tp-Te/QRS和Tp-Te/(QT·QRS)的ROC曲线显示曲线下面积分别为0.789(95%CI 0.667~0.910)和0.733(95%CI 0.585~0.880)。ROC曲线对应的值Tp-Te/QRS≥1.18,敏感性为100%,特异性82%;Tp-Te/(QT·QRS)≥0.0029,敏感性为100%,特异性82%。结论Tp-Te/QRS和Tp-Te/(QT·QRS)在预测SCD一级预防植入ICD的有效性方面有较高的临床应用价值。 展开更多
关键词 心血管病学 心脏性猝死 一级预防 Tp-te Tp-te/QRS Tp-te/(QT·QRS)
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