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Design of a wideband non-uniform microstrip line for complex impedance matching in automotive radar frequencies
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作者 ZHANG Shuang-Gen YU Tao +2 位作者 WANG Yu-Lan CHENG Zhi-Hua YAO Jian-Quan 《红外与毫米波学报》 北大核心 2025年第2期168-176,共9页
Microstrip transmission lines connecting to the millimeter wave radar chip and antenna significantly affect the radiation efficiency and bandwidth of the antenna.Here,a wideband non-uniform wavy microstrip line for co... Microstrip transmission lines connecting to the millimeter wave radar chip and antenna significantly affect the radiation efficiency and bandwidth of the antenna.Here,a wideband non-uniform wavy microstrip line for complex impedance in automotive radar frequency range is proposed.Unlike the gradient transmission line,the wavy structure is composed of periodically semi-circular segments.By adjusting the radius of the semi-circular,the surface current is varied and concentrated on the semi-circular segments,allowing a wider tunability range of the resonant frequency.The results reveal that the bandwidth of the loaded wavy transmission line antenna improves to 9.37 GHz,which is 5.81 GHz wider than that of the loaded gradient line.The gain and the half power beam width of the loaded antenna are about 14.69 dB and 9.58°,respectively.The proposed non-uniform microstrip line scheme may open up a route for realizing wideband millimeter-wave automotive radar applications. 展开更多
关键词 millimeter wave gradient line wavy transmission line broadband high gain array antenna
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Compact Ultra-Low Loss Optical True Delay Line on Thin Film Lithium Niobate
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作者 Yuan Ren Bo-Yang Nan +6 位作者 Rong-Bo Wu Yong Zheng Rui-Xue Liu Xue-Wen Wang Yun-Peng Song Min Wang Ya Cheng 《Chinese Physics Letters》 2025年第7期145-149,共5页
We report the fabrication of an 8-meter-long thin-flm lithium niobate optical true delay line using the photolithography-assisted chemomechanical etching technique,showing a low transmission loss of 0.036 dB/cm in the... We report the fabrication of an 8-meter-long thin-flm lithium niobate optical true delay line using the photolithography-assisted chemomechanical etching technique,showing a low transmission loss of 0.036 dB/cm in the conventional telecom band. 展开更多
关键词 conventional telecom band COMPACT transmission loss optical true delay line true delay line thin film ultra low loss lithium niobate
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China’s Sea Lines of Communication Security: A Perspective from a Holistic Approach to National Security
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作者 Wang Xu 《China International Studies》 2025年第4期31-68,共38页
Sea lines of communication(SLOCs)security has long been a strategic concern for major powers.Following the establishment of the People’s Republic of China,the country’s focus was on the traditional security aspects ... Sea lines of communication(SLOCs)security has long been a strategic concern for major powers.Following the establishment of the People’s Republic of China,the country’s focus was on the traditional security aspects of its SLOCs.Since the reform and opening-up era-and especially after the end of the Cold War-China has shifted its emphasis toward economic security.China’s SLOCs security bears on multiple dimensions of a holistic approach to national security,encompassing economic security,the safety of its citizens. 展开更多
关键词 holistic approach economic securitythe citizen safety sea lines communication slocs security national security sea lines communication security economic security
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Continuously Tunable Thin-Film Lithium Niobate Optical Delay Line with 293 ps Tuning Range
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作者 Lv-Bin Song Yong Zheng +8 位作者 Yuan Ren Bo-Yang Nan Rui-Xue Liu Hao-Zong Zhong Lin Li Min Wang Jin-Ming Chen Rong-Bo Wu Ya Cheng 《Chinese Physics Letters》 2025年第9期62-67,共6页
We present a compact optical delay line(ODL)with wide-range continuous tunability on thin-film lithium niobate platform.The proposed device integrates an unbalanced Mach-Zehnder interferometer(MZI)architecture with du... We present a compact optical delay line(ODL)with wide-range continuous tunability on thin-film lithium niobate platform.The proposed device integrates an unbalanced Mach-Zehnder interferometer(MZI)architecture with dual tunable couplers,where each coupler comprises two 2×2 multimode interferometers and a MZI phase-tuning section.Experimental results demonstrate continuous delay tuning from 0 to 293 ps through synchronized control of coupling coefficients,corresponding to a 4 cm path difference between interferometer arms.The measured delay range exhibits excellent agreement with theoretical predictions derived from ODL waveguide parameters.This result addresses critical challenges in integrated photonic systems that require precise temporal control,particularly for applications in optical communications and quantum information processing,where a wide tuning range is paramount. 展开更多
关键词 continuous tunable thin film lithium niobate optical delay line wide range continuous tunability delay tuning optical delay line odl unbalanced Mach Zehnder interferometer synchronized control coupling coefficientscorresponding dual tunable couplers cm path difference interfe
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Overall survival with frontline vs subsequent anti-epidermal growth factor receptor therapies in unresectable,RAS/BRAF wild-type,leftsided metastatic colorectal cancer
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作者 Nussara Pakvisal Richard M Goldberg +5 位作者 Chirawadee Sathitruangsak Witthaya Silaphong Satawat Faengmon Nattaya Teeyapun Chinachote Teerapakpinyo Suebpong Tanasanvimon 《World Journal of Clinical Oncology》 2025年第3期57-67,共11页
BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metasta... BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metastatic colorectal cancer(mCRC).Several studies have also demonstrated the benefit of anti-EGFR therapy in sub-sequent line settings for this patient population.However,direct evidence com-paring the effectiveness of frontline vs subsequent anti-EGFR therapy remains limited,leaving a crucial gap in guiding optimal treatment strategies.AIM To compare overall survival(OS)between frontline and subsequent anti-EGFR treatment in patients with unresectable,RAS and BRAF wild-type,left-sided mCRC.METHODS We retrospectively reviewed the medical records of mCRC patients treated at The King Chulalongkorn Memorial Hospital and Songklanagarind Hospital,Thailand,between January 2013 and April 2023.Patients were classified into two groups based on the sequence of their anti-EGFR treatment.The primary endpoint was OS.RESULTS Among 222 patients with a median follow-up of 29 months,no significant difference in OS was observed between the frontline and subsequent-line groups(HR 1.03,95%CI:0.73-1.46,P=0.878).The median OS was 35.53 months(95%CI:26.59-44.47)for the frontline group and 31.60 months(95%CI:27.83-35.37)for the subsequent-line group.In the subsequent-line group,71 patients(32.4%)who ultimately never received anti-EGFR therapy had a significantly worse median OS of 19.70 months(95%CI:12.87-26.53).CONCLUSION Frontline and subsequent-line anti-EGFR treatments provide comparable OS in unresectable,RAS/BRAF wild-type,left-sided mCRC patients,but early exposure is vital for those unlikely to receive subsequent therapy. 展开更多
关键词 Metastatic colorectal cancer Anti-epidermal growth factor receptor FRONTline Subsequent line RAS wild-type metastatic colorectal cancer BRAF wild-type metastatic colorectal cancer Left-sided metastatic colorectal cancer Overall survival
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A 2.69 ppm/℃ bandgap reference with 42 ppm/V line sensitivity for battery management system 被引量:1
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作者 Jing Wang Feixiang Zhang +2 位作者 Zhiyuan He Hui Zhang Lin Cheng 《Journal of Semiconductors》 2025年第6期31-42,共12页
This paper introduces a high-precision bandgap reference(BGR)designed for battery management systems(BMS),fea-turing an ultra-low temperature coefficient(TC)and line sensitivity(LS).The BGR employs a current-mode sche... This paper introduces a high-precision bandgap reference(BGR)designed for battery management systems(BMS),fea-turing an ultra-low temperature coefficient(TC)and line sensitivity(LS).The BGR employs a current-mode scheme with chopped op-amps and internal clock generators to eliminate op-amp offset.A low dropout regulator(LDO)and a pre-regula-tor enhance output driving and LS,respectively.Curvature compensation enhances the TC by addressing higher-order nonlinear-ity.These approaches,effective near room temperature,employs trimming at both 20 and 60°C.When combined with fixed cur-vature correction currents,it achieves an ultra-low TC for each chip.Implemented in a CMOS 180 nm process,the BGR occu-pies 0.548 mm²and operates at 2.5 V with 84μA current draw from a 5 V supply.An average TC of 2.69 ppm/℃ with two-point trimming and 0.81 ppm/℃ with multi-point trimming are achieved over the temperature range of-40 to 125℃.It accommo-dates a load current of 1 mA and an LS of 42 ppm/V,making it suitable for precise BMS applications. 展开更多
关键词 bandgap reference high precision low temperature coefficient small line sensitivity battery management system BMS
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GFRF R-CNN:Object Detection Algorithm for Transmission Lines
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作者 Xunguang Yan Wenrui Wang +3 位作者 Fanglin Lu Hongyong Fan Bo Wu Jianfeng Yu 《Computers, Materials & Continua》 SCIE EI 2025年第1期1439-1458,共20页
To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related issues.The increasing resolution of drone-cap... To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related issues.The increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution images.This study presents an enhanced object detection algorithm based on the Faster Regionbased Convolutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical components like insulators,shock hammers,and screws in transmission line.The algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine details.The Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and speed.The incorporation of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s accuracy.Experimental results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase compared to the standard Faster R-CNN.This highlights the effectiveness of the proposed algorithm in identifying electrical components in high-resolution aerial images. 展开更多
关键词 Faster R-CNN transmission line object detection GIOU GFR
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Aerodynamics and countermeasures of train-tail swaying inside single-line tunnels 被引量:1
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作者 Yadong SONG Yanpeng ZOU +2 位作者 Yuan YAO Ting QIN Longjiang SHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第5期438-455,共18页
In recent years,train-tail swaying of 160 km/h electric multiple units(EMUs)inside single-line tunnels has been heavily researched,because the issue needs to be solved urgently.In this paper,a co-simulation model of v... In recent years,train-tail swaying of 160 km/h electric multiple units(EMUs)inside single-line tunnels has been heavily researched,because the issue needs to be solved urgently.In this paper,a co-simulation model of vortex-induced vibration(VIV)of the tail car body is established,and the aerodynamics of train-tail swaying is studied.The simulation results were confirmed through a field test of operating EMUs.Furthermore,the influence mechanism of train-tail swaying on the wake flow field is studied in detail through a wind-tunnel experiment and a simulation of a reduced-scaled train model.The results demonstrate that the aerodynamic force frequency(i.e.,vortex-induced frequency)of the train tail increases linearly with train speed.When the train runs at 130 km/h,with a small amplitude of train-tail swaying(within 10 mm),the vortex-induced frequency is 1.7 Hz,which primarily depends on the nose shape of the train tail.After the tail car body nose is extended,the vortex-induced frequency is decreased.As the swaying amplitude of the train tail increases(exceeding 25 mm),the separation point of the high-intensity vortex in the train wake shifts downstream to the nose tip,and the vortex-induced frequency shifts from 1.7 Hz to the nearby car body hunting(i.e.,the primary hunting)frequency of 1.3 Hz,which leads to the frequency-locking phenomenon of VIV,and the resonance intensifies train-tail swaying.For the motor vehicle of the train tail,optimization of the yaw damper to improve its primary hunting stability can effectively alleviate train-tail swaying inside single-line tunnels.Optimization of the tail car body nose shape reduces the amplitude of the vortex-induced force,thereby weakening the aerodynamic effect and solving the problem of train-tail swaying inside the single-line tunnels. 展开更多
关键词 train tail swaying wind tunnel experiment field test single line tunnels AERODYNAMICS co simulation electric multiple units emus inside vortex induced vibration
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Impact of Single-Phase Automatic Recloser of Critical Transmission Line on the Stability of the Power Transmission Network
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作者 Chuulan Natsagdorj Ganbat Gantamir Erdenebileg Doljinsuren 《Journal of Power and Energy Engineering》 2025年第2期43-56,共14页
In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220... In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220 kV and a length of 250 km. These overhead power lines (L-213, L-214) connect the 220/110/35 kV “Songino” substation with the “Mandal” substation and form system networks. This paper presents the challenges encountered when implementing single-phase automatic reclosing (SPAR) devices and compares the changes in power system parameters before and after SPAR deployment for a long 220 kV line. Simulations and analyses were carried out using DIgSILENT PowerFactory software, focusing on rotor angle stability, and the overall impact on the power system during short-circuit faults. The evaluation also utilized measurement data from the Wide Area Monitoring System (WAMS) to compare system behavior pre- and post-implementation of SPAR. The findings reveal that SPAR significantly enhances system reliability and stability, effectively mitigating the risk of oscillations and stability loss triggered by short circuits. This improvement contributes to a more resilient power system, reducing the potential for disturbances caused by faults. 展开更多
关键词 Automatic Reclosing Single-Phase Automatic Reclosing Relay Protection Overhead Power lines System Stability Rotor Angle Stability
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Quick Author Guideline for OIL CROP SCIENCE
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《Oil Crop Science》 2025年第2期F0003-F0003,共1页
Manuscript Text and figures combined into a single file with page and line numbers up to3 MB in size in txt,doc,docx or tex files.Prepares your manuscript in the following order:Title page,Abstract,Introduction,Materi... Manuscript Text and figures combined into a single file with page and line numbers up to3 MB in size in txt,doc,docx or tex files.Prepares your manuscript in the following order:Title page,Abstract,Introduction,Materials and Methods,Results,Discussion,Acknowledgments,References,Tables,Figure Legends and Figures.Provide Cover letter and Supplementary Material(if necessary)at the same time. 展开更多
关键词 line oil crop text PAGE cover letter supplementary material SCIENCE MANUSCRIPT
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A Study of Multiple Molecular Lines at the 3 mm Band toward Gas Infalling Sources
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作者 Yang Yang Xi Chen +3 位作者 Zhibo Jiang Zhiwei Chen Shuling Yu Jun Li 《Research in Astronomy and Astrophysics》 2025年第5期230-245,共16页
The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemica properties of these sources and help us estimate their evolutionary stages.We report line detections within ... The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemica properties of these sources and help us estimate their evolutionary stages.We report line detections within the 3 mm band using the FTS wide-sideband mode of the IRAM 30 m telescope toward 20 gas-infalling sources.Using XCLASS,we identify the emission lines of up to 22 molecular species(including a few isotopologues)and on hydrogen radio recombination line in these sources.H^(13)CO^(+),HCO^(+),HCN,HNC,c-C_(3)H_(2),and CCH lines are detected in 15 sources.We estimate the rotation temperatures and column densities of these molecular species using the LTE radiative transfer model,and compare the molecular abundances of these sources with those from nine high mass star-forming regions reported in previous studies and with those from the chemical model.Our results sugges that G012.79-0.20,G012.87-0.22 clump A and B,and G012.96-0.23 clump A may be in the high-mass protostella object stage,while sources with fewer detected species may be in the earlier evolutionary stage.Additionally,th CCH and c-C_(3)H_(2)column densities in our sources reveal a linear correlation,with a ratio of N(CCH)/N(c-C_(3)H_(2)=89.2±5.6),which is higher than the ratios reported in the literature.When considering only sources with lowe column densities,this ratio decreases to 29.0±6.1,consistent with those of diffuse clouds.Furthermore,comparison between the N(CCH)/N(c-C_(3)H_(2))ratio and the sources’physical parameters reveals a correlation,with sources exhibiting higher ratios tending to have higher kinetic temperatures and H2column densities. 展开更多
关键词 GALAXIES star formation-ISM clouds-ISM lines and bands-ISM MOLECULES
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HiFAST: An H I Data Calibration and Imaging Pipeline for FAST.Ⅲ.Standing Wave Removal
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作者 Chen Xu Jie Wang +13 位作者 Yingjie Jing Fujia Li Hengqian Gan Ziming Liu Tiantian Liang Qingze Chen Zerui Liu Zhipeng Hou Hao Hu Huijie Hu Shijie Huang Peng Jiang Chuan-Peng Zhang Yan Zhu 《Research in Astronomy and Astrophysics》 2025年第1期247-261,共15页
The standing waves existing in radio telescope data are primarily due to reflections among the instruments,which significantly impact the spectral quality of the Five-hundred-meter Aperture Spherical radio Telescope(F... The standing waves existing in radio telescope data are primarily due to reflections among the instruments,which significantly impact the spectral quality of the Five-hundred-meter Aperture Spherical radio Telescope(FAST).Eliminating these standing waves for FAST is challenging given the constant changes in their phases and amplitudes.Over a ten-second period,the phases shift by 18°while the amplitudes fluctuate by 6 mK.Thus,we developed the fast Fourier transform(FFT)filter method to eliminate these standing waves for every individual spectrum.The FFT filter can decrease the rms from 3.2 to 1.15 times the theoretical estimate.Compared to other methods such as sine fitting and running median,the FFT filter achieves a median rms of approximately 1.2 times the theoretical expectation and the smallest scatter at 12%.Additionally,the FFT filter method avoids the flux loss issue encountered with some other methods.The FFT is also efficient in detecting harmonic radio frequency interference(RFI).In the FAST data,we identified three distinct types of harmonic RFI,each with amplitudes exceeding 100 mK and intrinsic frequency periods of 8.1,0.5,and 0.37 MHz,respectively.The FFT filter,proven as the most effective method,is integrated into the H I data calibration and imaging pipeline for FAST(HiFAST,https://hifast.readthedocs.io). 展开更多
关键词 methods data analysis-techniques image processing-galaxies ISM-radio lines GALAXIES
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Retraction:Puerarin inhibits proliferation and induces apoptosis by upregulation of miR-16 in bladder cancer cell line T24
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作者 Oncology Research Editorial Office 《Oncology Research》 2025年第4期993-993,共1页
The published article titled“Puerarin inhibits proliferation and induces apoptosis by upregulation of miR-16 in bladder cancer cell line T24”has been retracted from Oncology Research,Vol.26,No.8,2018,pp.1227–1234.
关键词 PUERARIN bladder cancer bladder cancer cell line T miR APOPTOSIS PROLIFERATION
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Evaluation of transgenic cotton lines expressing an insecticidal fern protein against whitefly,Bemisia tabaci(Gennadius)
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作者 KUMAR Rishi NAGRARE V.S. +14 位作者 SHAH Vivek SINGH Satnam PANDHER Suneet SINGH Satpal VERMA S.K. PAUL Debashis RATHORE Pankaj SHUKLA Anoop Kumar SINGH Mithlesh Kumar SAURABH Sharad KUMAR Harish KAUR Rupinderjeet SINGH Pradhyumna Kumar WAGHMARE V.N. PRASAD Y.G. 《Journal of Cotton Research》 2025年第2期163-177,共15页
Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with des... Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with desirable traits that wouldn’t be possible through conventional breeding methods.Transgenic crops have been developed for various traits globally.Whitefly,Bemisia tabaci(Gennadius)is one of the major sucking pests of cotton that cause significant damage to the cotton production.To combat whitefly infestations,researchers have developed four transgenic cotton lines expressing the fern protein.And those transgenic lines need to be evaluated for their performance against the target pest—whitefly.The evaluation was designed as controlled trials in polyhouse or muslin cloth cages under open-choice and no-choice conditions by comparing four transgenic cotton lines(A,B,C,and D)with three control groups,including untransformed cotton plants with a same genetic background of the transgenic line,conventionally bred whitefly-resistant cotton,and whitefly-susceptible cotton.In order to study the generational effect,the evaluation also involved studies on whitefly development in laboratory,muslin cloth cage,and polyhouse conditions.Results Both open-choice and no-choice experiments had shown that all the four transgenic cotton lines(A,B,C,and D)expressing the fern protein reduced adult whitefly numbers significantly compared with the control lines,except for the no-choice conditions in 2021,where the transgenic line C was non-significant different from the resistant control line.Notably,the nymphal population on the resistant control line was relatively low and nonsignificant different from the transgenic line C in 2021;and the transgenic lines A and C in 2022 under open-choice conditions.Under no-choice condition,the nymphal counts in the resistant control line was non-significant different from transgenic lines C and D in 2021;and transgenic line D in 2022.All transgenic lines showed significant decrease in egg hatching in 2021 and nymphal development in 2022,except for the transgenic line C which had no significant different in the nymphal development comparing with non-transgenic control lines in 2022.Adult emergence rates in both years of evaluation showed significant decrease in transgenic lines A and B comparing with the control lines.Additionally,the results showed a significant reduction in cotton leaf curl disease and sooty mold development in all the four transgenic lines compared with susceptible control under open-choice conditions,indicating potential benefits of transgenic lines beyond direct effect on whitefly control.Furthermore,the research explored the generational effects of the fern protein on whitefly which revealed the lowest fecundity in the transgenic line C across F0,F1 and F3 generations,lower egg hatching in F1 and F2 generations in transgenic lines A and B,shorter nymphal duration in F1 and F2 generations in transgenic line B,and the least total adult emergence in the transgenic line C in F0 and F3 generations.Conclusions These findings suggest that the transgenic cotton lines expressing fern protein disrupts whitefly populations and the life cycle to a certain extent.However,results are not consistent over generations and years of study,indicating these transgenic lines were not superior over control lines and need to be improved in future breeding. 展开更多
关键词 EVALUATION Fern protein Transgenic cotton lines WHITEFLY
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逆转座子LINE-1对293T细胞增殖及细胞形态的影响
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作者 李丹 刘红梅 张鹏 《中国生物工程杂志》 北大核心 2025年第7期1-10,共10页
目的:探索逆转座子LINE-1(long interspersed nuclear elements-1)编码的ORF-1p在维持293T细胞增殖和形态中的作用。方法:利用核糖核酸干扰(RNA interference,RNAi)技术,构建LINE-1 ORF-1p表达量下调的293T细胞系,通过qPCR(quantitative... 目的:探索逆转座子LINE-1(long interspersed nuclear elements-1)编码的ORF-1p在维持293T细胞增殖和形态中的作用。方法:利用核糖核酸干扰(RNA interference,RNAi)技术,构建LINE-1 ORF-1p表达量下调的293T细胞系,通过qPCR(quantitative polymerase chain reaction)和Western blot验证干扰效率,通过免疫荧光染色检测ORF-1p的表达和定位,通过细胞计数和克隆形成实验检测细胞增殖能力,通过鬼笔环肽和4’,6-二脒基-2-苯基吲哚(4’,6-diamidino-2-phenylindole,DAPI)染色分析细胞形态。结果:成功构建两种LINE-1敲低的293T细胞系,通过免疫荧光染色观察ORF-1p的表达定位,显示ORF-1p主要分布在细胞质,干扰LINE-1后ORF-1p表达减少;通过细胞计数和集落形成实验,发现下调ORF-1p后细胞的增殖能力和克隆形成能力显著降低(P<0.05);通过鬼笔环肽标记细胞骨架,DAPI标记细胞核,相差显微镜和共聚焦显微镜观察干扰LINE-1后细胞形态,结果显示,下调ORF-1p后shL1-749细胞面积减小,细胞圆润度增加(P<0.05)。结论:成功构建了LINE-1敲低的293T细胞系,发现下调ORF-1p蛋白能够抑制293T细胞的生长,改变细胞形态,为进一步了解LINE-1在细胞增殖和调控中的分子机制奠定了基础。 展开更多
关键词 line-1 ORF-1p RNAI 293T 细胞增殖 细胞形态
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ISOPERIMETRIC INEQUALITIES FOR INTEGRAL GEOMETRIC INVARIANTS OF RANDOM LINES
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作者 Gaoyong ZHANG 《Acta Mathematica Scientia》 2025年第1期189-199,共11页
Isoperimetric type inequalities for integral geometric invariants of random lines in the Euclidean space are shown.Entropy inequalities of probability densities on the affine Grassmann manifold of lines are given.
关键词 isoperimetric inequality convex body random points random lines chord integral Riesz potential ENTROPY
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Development of Gossypium hirsutum–Gossypium raimondii introgression lines and their use in QTL mapping of agricultural traits
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作者 Liang Wang Nijiang Ai +12 位作者 Zechang Zhang Chenhui Zhou Guoli Feng Sheng Cai Ningshan Wang Liuchun Feng Yu Chen Min Xu Yingying Wang Haoran Yue Mengfei Chen Liangshuai Xing Baoliang Zhou 《Journal of Integrative Agriculture》 2025年第5期1688-1703,共16页
Gossypium raimondii(2n=2x=26,D_(5)),an untapped wild species,is the putative progenitor of the D-subgenome of G.hirsutum(2n=4x=52,AD_(1)),an extensively cultivated species.Here,we developed a G.hirsutum(recipient)–G.... Gossypium raimondii(2n=2x=26,D_(5)),an untapped wild species,is the putative progenitor of the D-subgenome of G.hirsutum(2n=4x=52,AD_(1)),an extensively cultivated species.Here,we developed a G.hirsutum(recipient)–G.raimondii(donor)introgression population to exploit the favorable QTLs/genes and mapped potential quantitative trait loci(QTLs)from wild cotton species.The introgression population consisted of 256 lines with an introgression rate of 52.33%for the G.raimondii genome.The introgression segment length range was 0.03–19.12 Mb,with an average of 1.22 Mb.The coverage of total introgression fragments from G.raimondii was 386.98 Mb.Further genome-wide association analysis(Q+K+MLM)and QTL mapping(RSTEP-LRT)identified 59 common QTLs,including 14 stable QTLs and six common QTL(co-QTL)clusters,and one hotspot of micronaire(MIC).The common QTLs for seed index all showed positive additive effects,while the common QTLs for boll weight all had negative additive effects,indicating that the linkage between seed index and boll weight could be broken.QTLs for lint percentage showed positive effects and could be beneficial for improving cotton yield.Most QTLs for fiber quality had negative additive effects,implying these QTLs were domesticated/improved in G.hirsutum.A few fiber quality QTLs showed positive additive effects,so they could be used to improve cotton fiber quality.The introgression lines developed could be useful for molecular marker-assisted breeding and mapping QTLs precisely for mining desirable genes from the wild species G.raimondii.Such genes can improve cultivated cotton in the future through a designbreeding approach. 展开更多
关键词 Gossypium hirsutum Gossypium raimondii introgression lines YIELD fiber quality quantitative trait locus
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Formation of Damaging Surface Winds in a Bow-shaped Squall Line Mature Stage over South China
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作者 JIANG Ping CHEN Gui-xing +3 位作者 ZHANG Fen WU Yao ZHU Hao-nan ZHOU Rui-lin 《Journal of Tropical Meteorology》 2025年第1期17-29,共13页
Observational analyses and convection-permitting simulations are conducted to study an extreme event of damaging surface winds within a bow-shaped squall line over South China.Prevailing explanations for the formation... Observational analyses and convection-permitting simulations are conducted to study an extreme event of damaging surface winds within a bow-shaped squall line over South China.Prevailing explanations for the formation of damaging surface winds were applied to investigate the detailed processes at the mature stage of a squall line in a complicated real-world scenario.It is shown that environmental vertical wind shear was adequately strong to cause a shearing vorticity,and the shearing vorticity was comparable to the baroclinic vorticity by a cold pool.The balance led to strong upward motions at the leading edge of the squall line and brought plenty of rainfall.The descending rainfall cooled the surrounding air and entrained the upper-level cold air downward to the lower level,strengthening the cold pool by excessive evaporation and melting.The cold pool accelerated the propagation speed of the squall line and caused extensive wind damage at the surface.Meanwhile,the horizontal vortex lines at the leading edge of the cold pool were lifted by frontal updrafts and tilted to form the anti-cyclonic vortex at the middle level.This maintained and intensified the rearinflow jet behind the apex of bow echo in association with a notable midlevel pressure gradient.The rear-inflow jet was then transported downward to the surface by descending condensate,leading to damaging winds there.Other factors,such as environmental flows,however,contributed less to the damaging surface winds. 展开更多
关键词 bow echo damaging winds cold pool rear-inflow jet vortex line tilting
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Exploring Optimization Strategies for Island Power Grid Line Layout Oriented Towards Large-Scale Distributed Renewable Energy Integration
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作者 Zhenhuan Song Wenxin Liu 《Proceedings of Business and Economic Studies》 2025年第4期495-502,共8页
The construction of island power grids is a systematic engineering task.To ensure the safe operation of power grid systems,optimizing the line layout of island power grids is crucial.Especially in the current context ... The construction of island power grids is a systematic engineering task.To ensure the safe operation of power grid systems,optimizing the line layout of island power grids is crucial.Especially in the current context of large-scale distributed renewable energy integration into the power grid,conventional island power grid line layouts can no longer meet actual demands.It is necessary to combine the operational characteristics of island power systems and historical load data to perform load forecasting,thereby generating power grid line layout paths.This article focuses on large-scale distributed renewable energy integration,summarizing optimization strategies for island power grid line layouts,and providing a solid guarantee for the safe and stable operation of island power systems. 展开更多
关键词 Island power grid line layout Optimization strategy Distributed renewable energy LARGE-SCALE
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Efficient and lightweight 3D building reconstruction from drone imagery using sparse line and point clouds
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作者 Xiongjie YIN Jinquan HE Zhanglin CHENG 《虚拟现实与智能硬件(中英文)》 2025年第2期111-126,共16页
Efficient three-dimensional(3D)building reconstruction from drone imagery often faces data acquisition,storage,and computational challenges because of its reliance on dense point clouds.In this study,we introduced a n... Efficient three-dimensional(3D)building reconstruction from drone imagery often faces data acquisition,storage,and computational challenges because of its reliance on dense point clouds.In this study,we introduced a novel method for efficient and lightweight 3D building reconstruction from drone imagery using line clouds and sparse point clouds.Our approach eliminates the need to generate dense point clouds,and thus significantly reduces the computational burden by reconstructing 3D models directly from sparse data.We addressed the limitations of line clouds for plane detection and reconstruction by using a new algorithm.This algorithm projects 3D line clouds onto a 2D plane,clusters the projections to identify potential planes,and refines them using sparse point clouds to ensure an accurate and efficient model reconstruction.Extensive qualitative and quantitative experiments demonstrated the effectiveness of our method,demonstrating its superiority over existing techniques in terms of simplicity and efficiency. 展开更多
关键词 3D reconstruction line clouds Sparse clouds Lightweight models
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