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Rapid Phase Ambiguity Elimination Methods for DOA Estimator via Hybrid Massive MIMO Receive Array

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Chinese Journal of Electronics 2024年第1期33卷 175-184页

作者： Xichao zhan Zhongwen SUN Feng shu Yiwen CHEN Xin CHENG Yuanyuan WU Qi zhanG Yifan LI Peng zhanG School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology

For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of Max-RP.To achieve the Cramer Rao lower bound, a Root-MUSIC plus Max-RP-QI scheme is developed. Simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUSIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4 d B compared to the Cramer Rao lower bound.

关键词： Hybrid analog and digital Direction of arrival Massive hybrid multiple-input multiple-output Phase ambiguity Low computational complexity

Androgen signaling inhibits de novo lipogenesis to alleviate lipid deposition in zebrafish

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Zoological Research 2024年第2期45卷 355-366页

作者： Jing-Yi Jia Guang-Hui Chen Ting-Ting shu Qi-Yong Lou Xia Jin Jiang-Yan He Wu-Han Xiao Gang Zhai zhan Yin College of Fisheries Huazhong Agriculture UniversityWuhanHubei 430070China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China Hubei Key Laboratory of Three Gorges Project for Conservation of Fishes Chinese Sturgeon Research InstituteChina Three Gorges CorporationYichangHubei 443100China Hubei Hongshan Laboratory Huazhong Agriculture UniversityWuhanHubei 430070China Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100049China

Testosterone is closely associated with lipid metabolism and known to affect body fat composition and muscle mass in males.However,the mechanisms by which testosterone acts on lipid metabolism are not yet fully understood,especially in teleosts.In this study,cyp17a1-/-zebrafish(Danio rerio)exhibited excessive visceral adipose tissue(VAT),lipid content,and up-regulated expression and activity of hepatic de novo lipogenesis(DNL)enzymes.The assay for transposase accessible chromatinwithsequencing(ATAC-seq)results demonstrated that chromatin accessibility of DNL genes was increased in cyp17a1-/-fish compared to cyp17a1+/+male fish,including stearoyl-CoA desaturase(scd)and fatty acid synthase(fasn).Androgen response element(ARE)motifs in the androgen signaling pathway were significantly enriched in cyp17a1+/+male fish but not in cyp17a1-/-fish.Both androgen receptor(ar)-/-and wildtype(WT)zebrafish administered with Ar antagonist flutamide displayed excessive visceral adipose tissue,lipid content,and up-regulated expression and activity of hepatic de novo lipogenesis enzymes.The Ar agonist BMS-564929 reduced the content of VAT and lipid content,and down-regulated acetyl-CoA carboxylase a(acaca),fasn,and scd expression.Mechanistically,the rescue effect of testosterone on cyp17a1-/-fish in terms of phenotypes was abolished when ar was additionally depleted.Collectively,these findings reveal that testosterone inhibits lipid deposition by down-regulating DNL genes via Ar in zebrafish,thus expanding our understanding of the relationship between testosterone and lipid metabolism in teleosts.

关键词： Cyp17a1 Testosterone Androgen receptor De novo lipogenesis Fatty acid synthesis

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Context‑dependent antioxidant defense system(ADS)‑based stress memory in response to recurrent environmental challenges in congeneric invasive species

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Marine Life Science & Technology 2024年第2期6卷 315-330页

作者： Hanxi Li Xuena Huang Aibin zhan Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Marine ecosystems are facing escalating environmental fluctuations owing to climate change and human activities,imposing pressures on marine species.To withstand recurring environmental challenges,marine organisms,especially benthic species lacking behavioral choices to select optimal habitats,have to utilize well-established strategies such as the antioxidant defense system(ADS)to ensure their survival.Therefore,understanding of the mechanisms governing the ADS-based response is essential for gaining insights into adaptive strategies for managing environmental challenges.Here we conducted a com-parative analysis of the physiological and transcriptional responses based on the ADS during two rounds of'hypersalinity-recovery'challenges in two model congeneric invasive ascidians,Ciona robusta and C.savignyi.Our results demonstrated that C.savignyi exhibited higher tolerance and resistance to salinity stresses at the physiological level,while C.robusta demonstrated heightened responses at the transcriptional level.We observed distinct transcriptional responses,particularly in the utilization of two superoxide dismutase(SOD)isoforms.Both Ciona species developed physiological stress memory with elevated total SOD(T-SOD)and glutathione(GSH)responses,while only C.robusta demonstrated transcriptional stress memory.The regulatory distinctions within the Nrf2-Keap1 signalling pathway likely explain the formation disparity of transcriptional stress memory between both Ciona species.These findings support the'context-dependent stress memory hypothesis',emphasizing the emergence of species-specific stress memory at diverse regulatory levels in response to recurrent environmental challenges.Our results enhance our understanding of the mechanisms of environmental challenge manage-ment in marine species,particularly those related to the ADS.

关键词： Antioxidant defense Ascidian Biological invasion Environmental stress Stress memory

Gelfand-Kirillov Dimension and Reducibility of Scalar Generalized Verma Modules for Classical Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第3期40卷 658-706页

作者： zhan Qiang BAI Jing JIANG School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China E-mail:zqbai@*** jjsd6514@***

Let g be a classical complex simple Lie algebra and q be a parabolic subalgebra.Let M be a generalized Verma module induced from a one dimensional representation of q.Such M is called a scalar generalized Verma module.In this paper,we will determine the reducibility of scalar generalized Verma modules associated to maximal parabolic subalgebras by computing explicitly the Gelfand-Kirillov dimension of the corresponding highest weight modules.

关键词： Generalized Verma module Gelfand-Kirillov dimension Young tableau

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Research on the prognostic value of adjusting intraperitoneal threedimensional quality evaluation mode in laparoscopic cholecystectomy patients

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1078-1086页

作者： Yuan Zhou zhan-Qing Chen Operating Room Lianyungang Hospital of Traditional Chinese MedicineLianyungang 222000Jiangsu ProvinceChina Operating Room The Second People's Hospital of Lianyungang Affiliated to Kangda College of Nanjing Medical UniversityLianyungang 222000Jiangsu ProvinceChina

BACKGROUND Benign gallbladder diseases have become a high-prevalence condition not only in China but also worldwide.The main types of benign gallbladder diseases include gallbladder polyps,acute and chronic cholecystitis,and gallstones,with gallstones being the most common,accounting for over 70%of cases.Although the mortality rate of benign gallbladder diseases is low,they carry obvious potential risks.Studies have shown that an increased incidence of benign gallbladder diseases can increase the risk of cardiovascular diseases and gallbladder cancer,resulting in a substantial disease burden on patients and their families.AIM To assess the medical utility of the Configuration-Procedure-Consequence(CPC)three-dimensional quality evaluation model in modulating the prognosis of laparoscopic cholecystectomy patients.METHODS A total of 98 patients who underwent laparoscopic cholecystectomy in our hospital from February 2020 to January 2022 were selected as the subjects.According to the random number table method,they were divided into a study group and a control group,with 49 patients in each group.The control group received routine perioperative care,while the study group had the addition of the CPC three-dimensional quality evaluation.The postoperative recovery-related indicators(time to first flatus,time to oral intake,time to ambulation,hospital stay),stress indicators(cortisol and adrenaline levels),distinctions in anxiety and RESULTS The time to first flatus,time to oral intake,time to ambulation,and hospital stay of the study group patients were obviously lower than those of the control group patients,with statistical significance(P0.05).However,on the 3rd day after surgery,the cortisol and adrenaline levels,as well as SAS and SDS scores of the study gr

关键词： Configuration-Procedure-Consequence Three-dimensional quality evaluation Laparoscopic Cholecystectomy Recovery process Anxiety and depression Complications

Mega-Constellations Based TT&C Resource Sharing: Keep Reliable Aeronautical Communication in an Emergency

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China Communications 2024年第2期21卷 1-16页

作者： Haoran Xie Yafeng zhan Jianhua Lu Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

With the development of the transportation industry, the effective guidance of aircraft in an emergency to prevent catastrophic accidents remains one of the top safety concerns. Undoubtedly, operational status data of the aircraft play an important role in the judgment and command of the Operational Control Center(OCC). However, how to transmit various operational status data from abnormal aircraft back to the OCC in an emergency is still an open problem. In this paper, we propose a novel Telemetry, Tracking,and Command(TT&C) architecture named Collaborative TT&C(CoTT&C) based on mega-constellation to solve such a problem. CoTT&C allows each satellite to help the abnormal aircraft by sharing TT&C resources when needed, realizing real-time and reliable aeronautical communication in an emergency. Specifically, we design a dynamic resource sharing mechanism for CoTT&C and model the mechanism as a single-leader-multi-follower Stackelberg game. Further, we give an unique Nash Equilibrium(NE) of the game as a closed form. Simulation results demonstrate that the proposed resource sharing mechanism is effective, incentive compatible, fair, and reciprocal. We hope that our findings can shed some light for future research on aeronautical communications in an emergency.

关键词： aeronautical emergency communication mega-constellation networked TT&C resource allocation stackelberg game

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A Review on the Mullins Effect in Tough Elastomers and Gels

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Acta Mechanica Solida Sinica 2024年第2期37卷 181-214页

作者： Lin zhan Shaoxing Qu Rui Xiao MOE Key Lab of Disaster Forecast and Control in Engineering College of Mechanics and Construction EngineeringJinan UniversityGuangzhou510632China State Key Laboratory of Fluid Power and Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering MechanicsZhejiang UniversityHangzhou310027China

Tough elastomers and gels have garnered broad research interest due to their wide-ranging potential applications.However,during the loading and unloading cycles,a clear stress softening behavior can be observed in many material systems,which is also named as the Mullins effect.In this work,we aim to provide a complete review of the Mullins effect in soft yet tough materials,specifically focusing on nanocomposite gels,double-network hydrogels,and multi-network elastomers.We first revisit the experimental observations for these soft materials.We then discuss the recent developments of constitutive models,emphasizing novel developments in the damage mechanisms or network representations.Some phenomenological models will also be briefly introduced.Particular attention is then placed on the anisotropic and multiaxial modeling aspects.It is demonstrated that most of the existing models fail to accurately predict the multiaxial data,posing a significant challenge for developing future anisotropic models tailored for tough gels and elastomers.

关键词： Mullins effect Double-network hydrogels Nanocomposite gels Multi-network elastomers Anisotropic damage model Multiaxial model

Recent Advances in Enantioselective Reactions of Terminal Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第7期42卷 760-776页

作者： Qihang Guo Xbxuzhong She zhan Lu Centerof ChemistryforFrontier Technologies Departmentof ChemistryZhejiang UniversityHangzhouZhejiang 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center HangzhouZhejiang 311215China College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China

α-Olefins as aliphatic terminal alkenes could be obtained easily from numerous contemporary synthetic reactions as well as petro-chemical industry,and also found in natural products.Compared to the alkenes attaching the directing groups or activating group,the catalytic asymmetric reaction of unactivated terminal alkenes presents great challenges due to the weak electron effect and small steric hindrance effect.This review mainly summarizes the latest progress of the asymmetric reaction of unactivated terminal olefins since 2016.

关键词： Asymmetric catalysis Terminal unactivated alkenes Hydrofunctionalization Difunctionalization Metal-catalyzed

Kinetic model of vibration screening for granular materials based on biological neural network

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Particuology 2024年第5期88卷 98-106页

作者： zhan Zhao Yan zhang Fang Qin Mingzhi Jin School of Agricultural Engineering Jiangsu UniversityZhenjiang212013China Shandong Academy of Agricultural Machinery Sciences Ji'nan250100China

The kinetic model is the theoretical basis for optimizing the structure and operation performance of vibration screening devices.In this paper,a biological neurodynamic equation and neural connections were established according to the motion and interaction properties of the material under vibration excitation.The material feeding to the screen and the material passing through apertures were considered as excitatory and inhibitory inputs,respectively,and the generated stable neural activity landscape was used to describe the material distribution on the 2D screen surface.The dynamic process of material vibration screening was simulated using discrete element method(DEM).By comparing the similarity between the material distribution established using biological neural network(BNN)and that obtained using DEM simulation,the optimum coefficients of BNN model under a certain screening parameter were determined,that is,one relationship between the BNN model coefficients and the screening operation parameters was established.Different screening parameters were randomly selected,and the corresponding relationships were established as a database.Then,with straw/grain ratio,aperture diameter,inclination angle,vibration strength in normal and tangential directions as inputs,five independent adaptive neuro-fuzzy inference systems(ANFIS)were established to predict the optimum BNN model coefficients,respectively.The training results indicated that ANFIS models had good stability and accuracy.The flexibility and adaptability of the proposed BNN method was demonstrated by modeling material distribution under complex feeding conditions such as multiple regions and non-uniform rate.

关键词： Kinetic model Material distribution Vibration screening Biological neural network DEM simulation Adaptive neuro-fuzzy inference systems