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Compressed sensing-based structured joint channel estimation in a multi-user massive MIMO system

结构化学 2024年第3期43卷 3-9页

作者： Kun zhang Ni Dan Dan-Dan Ren ruo-yu zhang Xiaoyan Lu Ya-Pan Wu Li-Lei zhang Hong-Ru Fu Dong-Sheng Li College of Materials and Chemical Engineering China Three Gorges UniversityYichang443002PR China College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyang471934PR China College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyang471934PR China College of Materials and Chemical Engineering China Three Gorges UniversityYichang443002PR China

Achieving high heat-resisting room temperature phosphorescence(RTP)performance and robust white emission from pure small molecules is a meaningful but challenging ***,a simple donor-acceptor(D-A)molecule,9-(1H-benzotriazol-1-ylmethyl)-9H-carbazole(CzBtrz),was *** simple molecule not only exhibits multiple emissions including white light,thermally activated delayed fluorescence(TADF)and ultralong RTP with a lifetime of 988.54 ms at 545 nm,but also shows superhigh heat-resisting phosphorescence property which can maintain stability in a large temperature region from 77 to 350 K(ΔT=273 K),exceeding those of other RTP ***,this molecule shows the time-evolved dynamic *** experimental and theoretical an-alyses from CzBtrz crystal demonstrate that the intramolecular charge transfer(ICT)interaction and molecular stacking play an important role in the generation of ***,this work provides an efficient strategy to design ultrahigh heat-resistant RTP,ultralong RTP and single-phased white-light emitting materials.

关键词： Ultralong RTP TADF D-A molecule Heat-resisting White light

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Frontiers of Information Technology & Electronic Engineering 2017年第12期18卷 2082-2100页

作者： ruo-yu zhang Hong-lin ZHAO Shao-bo JIA Communication Research Center Harbin Institute of Technology Harbin 150080 China

Acquisition of accurate channel state information （CSI） at transmitters results in a huge pilot overhead in massive multiple input multiple output （MIMO） systems due to the large number of antennas in the base station （BS）. To reduce the overwhelming pilot overhead in such systems, a structured joint channel estimation scheme employing compressed sensing （CS） theory is proposed. Specifically, the channel sparsity in the angular domain due to the practical scattering environment is analyzed, where common sparsity and individual sparsity structures among geographically neighboring users exist in multi-user massive MIMO systems. Then, by equipping each user with multiple antennas, the pilot overhead can be alleviated in the framework of CS and the channel estimation quality can be improved. Moreover, a structured joint matching pursuit （SJMP） algorithm at the BS is proposed to jointly estimate the channel of users with reduced pilot overhead. Furthermore, the probability upper bound of common support recovery and the upper bound of channel estimation quality using the proposed SJMP algorithm are derived. Simulation results demonstrate that the proposed SJMP algorithm can achieve a higher system performance than those of existing algorithms in terms of pilot overhead and achievable rate.

关键词： Compressed sensing Multi-user massive multiple input multiple output (MIMO) Frequency-division duplexing Structured joint channel estimation Pilot overhead reduction

Strain Effects on Properties of Phosphorene and Phosphorene Nanoribbons:a DFT and Tight Binding Study

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Chinese Physics Letters 2018年第1期35卷 85-89页

作者： ruo-yu zhang Ji-Ming Zheng Zhen-Yi Jiang Department of Physics Northwest UniversityXi'an 710069 National Key Laboratory of Photoelectric Technology and Functional Materials Culture Base in Shaanxi Province National Photoelectric Technology and Functional Materials&Application of Science and Technology International Cooperation BaseInstitute of Photonics&Photon-TechnologyNorthwest UniversityXi'an 710069

We perform comprehensive density functional theory calculations of strain effect on electronic structure of black phosphorus(BP)and on BP *** uniaxial and biaxial strain are applied,and the dramatic change of BP's band structure is *** 0-8%uniaxial strain,the band gap can be modulated in the range of 0.55-1.06 eV,and a direct-indirect band gap transition causes strain over 4%in the y *** 0-8%biaxial strain,the band gap can be modulated in the range of 0.35-1.09 eV,and the band gap maintains *** strain to BP nanoribbon,the band gap value reduces or enlarges markedly either zigzag nanoribbon or armchair *** the orbital composition and using a tight-binding model we ascribe this band gap behavior to the competition between effects of different bond lengths on band *** results would enhance our understanding on strain effects on properties of BP and phosphorene nanoribbon.

关键词： Nanoribbons

Polyether-polyester and HMDI Based Polyurethanes:Effect of PLLA Content on Structure and Property

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Chinese Journal of Polymer Science 2019年第11期37卷 1152-1161页

作者： Lei Shi ruo-yu zhang Wu-Bin Ying Han Hu yu-Bin Wang Ya-Qian Guo Wen-Qin Wang Zhao-Bin Tang Jin Zhu Key Laboratory of Bio-based Polymeric Materials Technology and Application of Zhejiang Province Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Ningbo 315201 China School of Material Science and Chemical Engineering Ningbo University Ningbo 315211 China

Thermoplastic poly(ether-ester-urethane)s were synthesized from poly(L-lactide) diols (PLLA diols), polytetrahydrofuran diol (PTMG diols), 4,4'-dicyclohexylmethane diisocyanate (HMDI), and 1,4-butanediol (BDO) by a two-step reaction, and the morphology and property of the resultant TPU could be adjusted by varying the PLLA contents. The soft segment was composed of PLLA and PTMG diols. By controlling the percentage of PLLA in the soft segment, the glass transition temperature and mechanical properties of the polyurethanes could be regulated. Based on the FTIR spectrum, we found that two kinds of hydrogen bonding existed individually in soft matrix and hard domain. The hydrogen bonding in soft matrix was unstable, which could be destroyed during elongation. With in situ stretching WAXS and SAXS experiments, we found that the PLLA crystal was destroyed and the PLLA domain oriented along the stretch direction. Finally, we proposed a schematic model to illustrate the microstructures of these elastomers before and after stretch.

关键词： Poly(L-lactide) diol Polyurethane Mechanical property Hydrogen bonding

Hydrodynamic Characteristics of Undular Tidal Bores in the Qiantang River Based on Field Observations

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China Ocean Engineering 2024年第3期38卷 505-518页

作者： zhang Shu-yu PAN Cun-hong zhang Shen-yang LI ruo-hua CHENG Wenlong XIE Dong-feng Zhejiang Tongji Vocational College of Science and Technology Hangzhou 311231China Zhejiang Institute of Hydraulics and Estuary Hangzhou 310020China

Understanding the undular tidal bores in the Qiantang River is essential for effective river management and *** breaking tidal bores have been studied extensively, reports on undular tidal bores in the Qiantang Riverremain limited. Furthermore, observed data on undular tidal bores fulfilling the requirements of short measurementtime intervals, and spring, medium, and neap tide coverage, and providing detailed data for the global vertical stratificationof flow velocity are quite limited. Based on field observations at Qige in the Qiantang estuary, we analyzedthe characteristics of undular tidal bores. The results showed that the flooding amplitude (a) of the first wave isalways larger than its ebbing amplitude (b). Moreover, the vertical distribution of the maximum flood velocity exhibitesthree shapes, influenced by the tidal range, while that of the maximum ebb velocity exhibites a single shape. Duringthe initial phase of the flood tide in the spring and medium tides, the upper water body experiences multiple oscillatingchanges along the flow direction, corresponding to the alternating process of the crest and trough of the tide levelupon the arrival of the tidal bore. The tidal range is a crucial parameter in tidal bore hydrodynamics. By establishingthe relationship between hydrodynamic parameters and tidal range, other hydrodynamic parameters, such as the tidalbore height, maximum flood depth–averaged velocity, maximum flood stratified velocity at the measurement points,and duration of the flood tide current, can be effectively predicted, thereby providing an important reference for rivermanagement and maintenance.

关键词： tidal bores Qiantang Estuary tidal bore height tidal bore velocity propagation speed

Rotating magnetic field inhibits Aβ protein aggregation and alleviates cognitive impairment in Alzheimer’s disease mice

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Zoological Research 2024年第4期45卷 924-936页

作者： ruo-Wen Guo Wen-Jing Xie Biao yu Chao Song Xin-Miao Ji Xin-yu Wang Mei zhang Xin zhang High Magnetic Field Laboratory CAS Key Laboratory of High Magnetic Field and Ion Beam Physical BiologyHefei Institutes of Physical ScienceChinese Academy of SciencesHefeiAnhui 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefeiAnhui 230036China Institutes of Physical Science and Information Technology Anhui UniversityHefeiAnhui 230601China School of Life Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China

Amyloid beta(Aβ)monomers aggregate to form fibrils and amyloid plaques,which are critical mechanisms in the pathogenesis of Alzheimer’s disease(AD).Given the important role of Aβ1-42 aggregation in plaque formation,leading to brain lesions and cognitive impairment,numerous studies have aimed to reduce Aβaggregation and slow AD *** diphenylalanine(FF)sequence is critical for amyloid aggregation,and magnetic fields can affect peptide alignment due to the diamagnetic anisotropy of aromatic *** this study,we examined the effects of a moderate-intensity rotating magnetic field(RMF)on Aβaggregation and AD *** indicated that the RMF directly inhibited Aβamyloid fibril formation and reduced Aβ-induced cytotoxicity in neural cells in *** the AD mouse model APP/PS1,RMF restored motor abilities to healthy control levels and significantly alleviated cognitive impairments,including exploration and spatial and non-spatial memory *** examinations demonstrated that RMF reduced amyloid plaque accumulation,attenuated microglial activation,and reduced oxidative stress in the APP/PS1 mouse *** findings suggest that RMF holds considerable potential as a non-invasive,high-penetration physical approach for AD treatment.

关键词： lzheimer’s disease Rotating magnetic field Amyloid-β Cognitive function Alzheimer’s disease animal models

Double active sites promoting hydrogen evolution activity and stability of CoruoH/Co_(2)P by rapid hydrolysis

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Chinese Chemical Letters 2024年第7期35卷 206-211页

作者： Bin Dong Ning yu Qiu-yue Wang Jing-Ke Ren Xin-yu zhang Zhi-Jie zhang ruo-Yao Fan Da-Peng Liu Yong-Ming Chai State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Cobalt-based phosphides show excellent hydrogen evolution reaction(HER)performance,however,improving the intrinsic activity and stability of it in alkaline electrolyte still remains a ***,CoruoH/Co_(2)P/CF with heterojunction structure was developed by means of molten salt and rapid hydrolysis(30 s).The OH-from rapid surface hydrolysis of Co_(2)P as a hydrogen adsorption site can facilitate the formation of thin CoruoH layer as a water dissociation site,which may bring out better synergistic effect for alkaline ***,the covering of CoruoH can improve the stability of Co_(2)P for *** drives at 100 mA/cm^(2),it only requires overpotential of 81 mV in 1.0 mol/L KOH(25℃).Even at higher current density(1000 mA/cm^(2)),CoruoH/Co_(2)P/CF can also operate stability for at least 100 *** coupling with NiFe-LDH/IF in a two-electrode system,the voltage of NiFe-LDH/IF(+)||CoruoH/Co_(2)P/CF(-)at 1000 mA/cm^(2)is merely 1.77 V with 100 h,demonstrating great potential for water *** implementation of this work provides a new strategy and reference for the further improvement of transition metal phosphides as HER electrocatalysts.

关键词： CoruoH/Co_(2)P/CF Enhanced activity and stability Double active site Large current density Hydrogen evolution reaction

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Erythropoietin-induced hepatocyte receptor A2 regulates effect of pyroptosis on gastrointestinal colorectal cancer occurrence and metastasis resistance

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World Journal of Gastrointestinal Oncology 2024年第9期16卷 3781-3797页

作者： yu-Kun zhang Ran Shi ruo-yu Meng Shui-Li Lin Mei Zheng Department of Rehabilitation Medicine The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qianfoshan HospitalJinan 250014Shandong ProvinceChina Department of Minimally Invasive Comprehensive Treatment of Cancer Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina Department of Ana and Intestinal Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

Erythropoietin-induced hepatocyte receptor A2(EphA2)is a receptor tyrosine kinase that plays a key role in the development and progression of a variety of *** article reviews the expression of EphA2 in gastrointestinal(GI)colorectal cancer(CRC)and its regulation of *** is a form of programmed cell death that plays an important role in tumor *** have shown that EphA2 regulates pyrodeath through various signaling pathways,affecting the occurrence,development and metastasis of GI *** overexpression of EphA2 is closely related to the aggressiveness and metastasis of GI CRC,and the inhibition of EphA2 can induce pyrodeath and improve the sensitivity of cancer cells to *** addition,EphA2 regulates intercellular communication and the microenvironment through interactions with other cytokines and receptors,further influencing cancer *** role of EphA2 in GI CRC and its underlying mechanisms provide us with new perspectives and potential therapeutic targets,which have important implications for future cancer treatment.

关键词： Colorectal cancer Pyroptosis Erythropoietin-induced hepatocyte receptor A2 Tumor metastasis Drug resistance

N6-methyladenosine methylation regulates the tumor microenvironment of Epstein-Barr virus-associated gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2555-2570页

作者： yu zhang Fang Zhou Ming-yu zhang Li-Na Feng Jia-Lun Guan ruo-Nan Dong yu-Jie Huang Su-Hong Xia Jia-Zhi Liao Kai Zhao Department of Gastroenterology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina Institute of Liver and Gastrointestinal Diseases Hubei Key Laboratory of Hepato-Pancreato-Biliary DiseasesTongji Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina Department of Pharmacy Wuhan Fourth HospitalWuhan 430030Hubei ProvinceChina

BACKGROUND N6-methyladenosine(m6A)methylation modification exists in Epstein-Barr virus(EBV)primary infection,latency,and lytic *** also modifies EBV latent genes and lytic ***-associated gastric cancer(EBVaGC)is a distinctive molecular subtype of *** hypothesized EBV and m6A methylation regulators interact with each other in EBVaGC to differentiate it from other types of *** To investigate the mechanisms of m6A methylation regulators in EBVaGC to determine the differentiating factors from other types of *** First,The Cancer Gene Atlas and Gene Expression Omnibus databases were used to analyze the expression pattern of m6A methylation regulators between EBVaGC and EBV-negative GC(EBVnGC).Second,we identified Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment of m6A-related differentially expressed *** quantified the relative abundance of immune cells and inflammatory factors in the tumor microenvironment(TME).Finally,cell counting kit-8 cell proliferation test,transwell test,and flow cytometry were used to verify the effect of insulin-like growth factor binding protein 1(IGFBP1)in EBVaGC cell *** m6A methylation regulators were involved in the occurrence and development of *** with EBVnGC,the expression levels of m6A methylation regulators Wilms tumor 1-associated protein,RNA binding motif protein 15B,CBL proto-oncogene like 1,leucine rich pentatricopeptide repeat containing,heterogeneous nuclear ribonucleoprotein A2B1,IGFBP1,and insulin-like growth factor 2 binding protein 1 were significantly downregulated in EBVaGC(P<0.05).The overall survival rate of EBVaGC patients with a lower expression level of IGFBP1 was significantly higher(P=0.046).GO and KEGG functional enrichment analyses showed that the immunity pathways were significantly activated and rich in immune cell infiltration in *** with EBVnGC,the infiltration of activated CD4+T cells,activated CD8+T cel

关键词： N6-methyladenosine methylation Tumor microenvironment Epstein-Barr virus Gastric cancer Insulin-like growth factor binding protein 1

Acute suppurative terminal cholangitis:Clinical characteristics of a new subtype of acute cholangitis

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 293-299页

作者： Rong-Tao Zhu Ye Li Chi-Xian zhang Wei-Jie Wang ruo-Peng Liang Jian Li Kai Bai yu-Ling Sun Department of Hepatobiliary and Pancreatic Surgery the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Zhengzhou Key Laboratory of Hepatobiliary and Pancreatic Diseases Zhengzhou 450052China Institute of Hepatobiliary and Pancreatic Diseases Zhengzhou UniversityZhengzhou 450052China Department of Pathology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well *** explore this subtype of acute cholangitis,we described our clinical experience with ***:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August *** analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and ***:A total of 32 ASTC patients were included in the *** majority of the patients had a history of biliary operations,and clinical manifestations were occult and *** positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance *** with effective antibiotics was provided as soon as diagnosis was *** treatment,most patients had a good *** levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor ***:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed.

关键词： Acute suppurative terminal cholangitis Acute cholangitis Gram-negative bacterial infections Diagnosis Treatment