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一种基于CDMA的无线ATM介质访问控制协议

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桂林电子工业学院学报 2000年第2期20卷 27-32页

作者：肖炼斌郑继禹仇洪冰桂林电子工业学院电子信息分院 541004

提出了一种基于 CDMA的介质访问控制协议 ,通过较少的基站控制能支持话音 /数据等实时和非实时业务的传输并保证各自的服务质量要求。仿真表明协议能在各种条件下获得很好的性能并可以作为无线

关键词：介质访问控制协议码分多址异步转移模式移动

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ABR控制算法性能研究

桂林电子工业学院学报 2000年第2期20卷 21-26页

作者：陶光庆郑继禹仇洪冰桂林电子工业学院电子信息分院 541004

在考察了接入 IP业务时四种 ATM ABR流量控制算法之后 ,对网中存在 VBR背景流的情况下的性能进行了分析研究 ,发现通过计算机仿真 ,虽然计算 ACR的方法各异 ,四种算法均能够使网络提供持续。

关键词：流量控制 ABR业务 ATM网络 IP业务

Novel flexible and transparent microstrip low-pass filter design with Π-shaped DGS

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The Journal of China Universities of Posts and Telecommunications 2025年

作者： Liu Zhaohan Han Yunan qiu Xianbo Li Xianli College of Information Science and Technology， Beijing University of Chemical Technology

This paper proposes a new design for a transparent low-pass filter (LPF) using a flexible PTFE material and metallic copper. The transparent microstrip filter employs an asymmetric Π-shaped structure with dimensions of 260 mm × 13 mm × 0.148 mm， which owns a narrow transition band and achieves an insertion loss of less than 1.0 dB below 0.26 GHz. Furthermore， the insertion loss of the transparent microstrip filter can exceed 30 dB in the stopband of 1.02 GHz to 6.50 GHz. Square holes are added to the copper layer to improve the transparency of the LPF， and the filter performance can be adjusted by changing the square hole area and resolution. Additionally， multiple identical structures are cascaded to increase the insertion loss in the stopband while maintaining the passband. The transparent microstrip LPF has the characteristics of flexibility， high transparency， and significant insertion loss in the stopband， making it suitable for applications that require electromagnetic protection in a clear field of vision.

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Low-complexity channel estimation for wideband mmWave massive MIMO systems with uniform planar arrays

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The Journal of China Universities of Posts and Telecommunications 2025年

作者： Wang Haotian Liu Lizhou qiu Ling Zhang Lei School of Electronic and Information Engineering， University of Science and Technology of China

Millimeter-wave (mmWave) and massive multiple-input multiple-output (MIMO) are broadly recognized as key enabling technologies for the fifth generation communication systems. In this paper， a low-complexity angle-delay parameters estimation (ADPE) method was put forward for wideband mmWave systems with uniformly planar arrays (UPA). In particular， ADPE method effectively decouples the angle-delay parameters and converts the angle-delay estimation problem into three independent subproblems. Accordingly， the ability to devise an off-grid method based on discrete Fourier transform (DFT) with a closed-form solution for angle-delay estimation and potential path number acquisition can be realized. In actuality， only a limited number of potential paths are close to the true paths influenced by noise. Consequently， the removal of noise paths to acquire the corresponding true path gains through a sparsity adaptive path gains estimation (APGE) method is postulated. Finally， the simulation results substantiate the effectiveness of ADPE and APGE methods.

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Low-complexity and fast convergent multiuser detections for impulse UWB systems

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High Technology Letters 2008年第2期14卷 141-146页

作者：郑霖 qiu hongbing Department of Communication ＆ Information Engineering Guilin University of Electronic Technology Guilin 541004 P.R. China

To solve the problem that the conventional detections in DS-CDMA suffer from high complexity and poor robustness for the time-hopping pulse signals, the received pulse signals were remodeled, and a mulfipath-free detection scheme, which provides a simple approach to select samples of received signals, was introduced. By this scheme, the subsequent multiuser detection （MUD） would get rid of the mis- match due to the correlative multipath signal in IR-UWB. In addition, a computationally efficient recur-sive least squares （RLS） type algorithm based on least mean fourth （LMF） criterion is derived to suppress multi-access interference. The proposed multiuser detection algorithm performs well at low complexity, even in dense muhipath environment.

关键词： ultra-wideband multiuser detection (MUD) multipath interference (MPI) leastmean fourth (LMF)

AAV2-PDE6B restores retinal structure and function in the retinal degeneration 10 mouse model of retinitis pigmentosa by promoting phototransduction and inhibiting apoptosis

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Neural Regeneration Research 2025年第8期20卷 2408-2419页

作者： Ruiqi qiu Mingzhu Yang Xiuxiu Jin Jingyang Liu Weiping Wang Xiaoli Zhang Jinfeng Han Bo Lei Henan Eye Hospital Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Eye Institute Henan Academy of Innovations in Medical ScienceZhengzhouHenan ProvinceChina Branch of National Clinical Research Center for Ocular Disease Henan Provincial People’s HospitalZhengzhouHenan ProvinceChina Academy of Medical Science Zhengzhou UniversityZhengzhouHenan ProvinceChina

Retinitis pigmentosa is a group of inherited diseases that lead to retinal degeneration and photoreceptor cell ***,there is no effective treatment for retinitis pigmentosa caused by PDE6B ***-associated virus(AAV)-mediated gene therapy is a promising strategy for treating retinitis *** aim of this study was to explore the molecular mechanisms by which AAV2-PDE6B rescues retinal *** do this,we injected retinal degeneration 10(rd10)mice subretinally with AAV2-PDE6B and assessed the therapeutic effects on retinal function and structure using dark-and light-adapted electroretinogram,optical coherence tomography,and ***-independent acquisition-mass spectrometry-based proteomic analysis was conducted to investigate protein expression levels and pathway enrichment,and the results from this analysis were verified by real-time polymerase chain reaction and western ***2-PDE6B injection significantly upregulated PDE6βexpression,preserved electroretinogram responses,and preserved outer nuclear layer thickness in rd10 *** expressed proteins between wild-type and rd10 mice were closely related to visual perception,and treating rd10 mice with AAV2-PDE6B restored differentially expressed protein expression to levels similar to those seen in wild-type *** Encyclopedia of Genes and Genome analysis showed that the differentially expressed proteins whose expression was most significantly altered by AAV2-PDE6B injection were enriched in phototransduction ***,the phototransductionrelated proteins Pde6α,Rom1,Rho,Aldh1a1,and Rbp1 exhibited opposite expression patterns in rd10 mice with or without AAV2-PDE6B ***,Bax/Bcl-2,p-ERK/ERK,and p-c-Fos/c-Fos expression levels decreased in rd10 mice following AAV2-PDE6B *** data suggest that AAV2-PDE6B-mediated gene therapy promotes phototransduction and inhibits apoptosis by inhibiting the ERK signaling pathway and upr

关键词： apoptosis AAV2-PDE6B ERK1/2 gene therapy phototransduction proteomics rd10 retinitis pigmentosa

Nanograting‑Based Dynamic Structural Colors Using Heterogeneous Materials

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Nano-Micro Letters 2025年第3期17卷 138-151页

作者： Jingang Wang Haibo Yu Jianchen Zheng Yuzhao Zhang Hongji Guo Ye qiu Xiaoduo Wang Yongliang Yang Lianqing Liu State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Dynamic structuralcolors can change in response todifferent environmental *** ability remains effectiveeven when the size of the speciesresponsible for the structural coloris reduced to a few micrometers,providing a promising sensingmechanism for solving microenvironmentalsensing problems inmicro-robotics and ***, the lack of dynamicstructural colors that can encoderapidly, easily integrate, and accuratelyreflect changes in physical quantities hinders their use in microscale sensing applications. Herein, we present a 2.5-dimensionaldynamic structural color based on nanogratings of heterogeneous materials, which were obtained by interweaving a pH-responsive hydrogelwith an IP-L photoresist. Transverse gratings printed with pH-responsive hydrogels elongated the period of longitudinal grating in the swollenstate, resulting in pH-tuned structural colors at a 45° incidence. Moreover, the patterned encoding and array printing of dynamic structuralcolors were achieved using grayscale stripe images to accurately encode the periods and heights of the nanogrid structures. Overall, dynamicstructural color networks exhibit promising potential for applications in information encryption and in situ sensing for microfluidic chips.

关键词： Dynamic structural colors Four-dimensional printing pH-responsive Nanogrid Heterogeneous materials

An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu Zhe Wang MengXi Shi Willie Soon ShiCan qiu Department of Geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth Sciences(CERES) SalemMA 01970USA Institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

Resolving the developmental mechanisms of cardiac microthrombosis of SARS-CoV-2 based on single-cell transcriptome analysis

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Science China Life Sciences 2025年第1期68卷 103-115页

作者： Xizi Luo Nan Zhang Yuntao Liu Beibei Du Xuan Wang Tianxu Zhao Bingqiang Liu Shishun Zhao Jiazhang qiu Guoqing Wang State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Basic MedicineJilin University State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Veterinary MedicineJilin University College of Mathematics Jilin University Bioinformatic Lab School of MathematicsShandong University Department of Cardiology China-Japan Union HospitalJilin University

The coronavirus disease 2019（COVID-19） outbreak caused by the severe acute respiratory syndrome coronavirus-2（SARS-CoV-2） developed into a global health emergency. Systemic microthrombus caused by SARS-CoV-2 infection is a common complication in patients with COVID-19. Cardiac microthrombosis as a complication of SARS-CoV-2 infection is the primary cause of cardiac injury and death in patietns with severe COVID-19. In this study, we performed single-cell sequencing analysis of the right ventricular free wall tissue from healthy donors,patients who died during the hypercoagulable period of characteristic coagulation abnormality（CAC）, and patients who died during the fibrinolytic period of CAC. We collected 61,187 cells enriched in 24 immune cell subsets and 13 cardiac-resident cell subsets. We found that in the course of SARS-CoV-2 infected heart microthrombus, MYO1EhighRASGEF1Bhighmonocyte-derived macrophages promoted hyperactivation of the immune system and initiated the extrinsic coagulation pathway by activating chemokines CCL3, CCL5. This series of events is the main cause of cardiac microthrombi following SARS-CoV-2 infection. In a SARS-CoV-2 infected heart microthrombus, excessive immune activation is accompanied by an increase in cellular iron content, which in turn promotes oxidative stress and intensifies intercellular competition. This induces cells to alter their metabolic environment, resulting in increased sugar uptake via the glycosaminoglycan synthesis pathway. In addition, high levels of reactive oxygen species generated by elevated iron levels promote increased endogenous malondialdehyde synthesis in a subpopulation of cardiac endothelial cells. This exacerbates endothelial cell dysfunction and exacerbates the coagulopathy process.

关键词： SARS-CoV-2 cardiac microthrombosis immune hyperactivation cell competition