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Power Allocation for SE Maximization in Uplink Massive MIMO System Under Minimum Rate Constraint

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China Communications 2024年第3期21卷 104-117页

作者： Wang hui Yu Xiangbin Liu Fuyuan bai Jiawei College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

In this paper,we optimize the spectrum efficiency(SE)of uplink massive multiple-input multiple-output(MIMO)system with imperfect channel state information(CSI)over Rayleigh fading channel.The SE optimization problem is formulated under the constraints of maximum power and minimum rate of each user.Then,we develop a near-optimal power allocation(PA)scheme by using the successive convex approximation(SCA)method,Lagrange multiplier method,and block coordinate descent(BCD)method,and it can obtain almost the same SE as the benchmark scheme with lower complexity.Since this scheme needs three-layer iteration,a suboptimal PA scheme is developed to further reduce the complexity,where the characteristic of massive MIMO(i.e.,numerous receive antennas)is utilized for convex reformulation,and the rate constraint is converted to linear constraints.This suboptimal scheme only needs single-layer iteration,thus has lower complexity than the near-optimal scheme.Finally,we joint design the pilot power and data power to further improve the performance,and propose an two-stage algorithm to obtain joint PA.Simulation results verify the effectiveness of the proposed schemes,and superior SE performance is achieved.

关键词： imperfect CSI massive MIMO minimum rate constraint power allocation spectral efficiency

Influence of varied drought types on soil conservation service within the framework of climate change:insights from the Jinghe River Basin,China

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Journal of Arid Land 2024年第2期16卷 220-245页

作者： bai Jizhou LI Jing RAN hui ZHOU Zixiang DANG hui ZHANG Cheng YU Yuyang School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054China

Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,China.Investigating the influence of drought on soil conservation service is of great importance to regional environmental protection and sustainable development.However,there is little research on the coupling relationship between them.In this study,focusing on the Jinghe River Basin,China as a case study,we conducted a quantitative evaluation on meteorological,hydrological,and agricultural droughts(represented by the Standardized Precipitation Index(SPI),Standardized Runoff Index(SRI),and Standardized Soil Moisture Index(SSMI),respectively)using the Variable Infiltration Capacity(VIC)model,and quantified the soil conservation service using the Revised Universal Soil Loss Equation(RUSLE)in the historical period(2000-2019)and future period(2026-2060)under two Representative Concentration Pathways(RCPs)(RCP4.5 and RCP8.5).We further examined the influence of the three types of drought on soil conservation service at annual and seasonal scales.The NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP)dataset was used to predict and model the hydrometeorological elements in the future period under the RCP4.5 and RCP8.5 scenarios.The results showed that in the historical period,annual-scale meteorological drought exhibited the highest intensity,while seasonal-scale drought was generally weakest in autumn and most severe in summer.Drought intensity of all three types of drought will increase over the next 40 years,with a greater increase under the RCP4.5 scenario than under the RCP8.5 scenario.Furthermore,the intra-annual variation in the drought intensity of the three types of drought becomes smaller under the two future scenarios relative to the historical period(2000-2019).Soil conservation service exhibits a distribution pattern characterized by high levels in the southwest and southeast and lower levels in the north,and this pattern has remained consistent both in the historical and future pe

关键词： meteorological drought hydrological drought agricultural drought soil conservation service Variable Infiltration Capacity(VIC)model Revised Universal Soil Loss Equation(RUSLE) Jinghe River Basin

Neuroimmune interactions and their roles in neurodegenerative diseases

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Fundamental Research 2024年第2期4卷 251-261页

作者： bai-Rong Chen Ting Wu Ting-hui Chen Yun Wang Neuroscience Research Institute and Department of Neurobiology School of Basic Medical SciencesKey Laboratory for NeuroscienceMinistry of Education/National Health Commission and State Key Laboratory of Natural and Biomimetic DrugsPeking UniversityBeijing 100083China PKU-IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China

The nervous system possesses bidirectional,sophisticated and delicate communications with the immune system.These neuroimmune interactions play a vitally important role in the initiation and development of many disorders,especially neurodegenerative diseases.Although scientific advancements have made tremendous progress in this field during the last few years,neuroimmune communications are still far from being elucidated.By organizing recent research,in this review,we discuss the local and intersystem neuroimmune interactions and their roles in Alzheimer’s disease,Parkinson’s disease and amyotrophic lateral sclerosis.Unveiling these will help us gain a better understanding of the process of interplay inside the body and how the organism maintains homeostasis.It will also facilitate a view of the diseases from a holistic,pluralistic and interconnected perspective,thus providing a basis of developing novel and effective methods to diagnose,intervene and treat diseases.

关键词： Nervous system Immune system Neuroimmune interactions Alzheimer’s disease Parkinson’s disease Amyotrophic lateral sclerosis

Surface reconstruction and structural transformation of twodimensional Ni-Fe MOFs for oxygen evolution in seawater media

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Nano Research 2024年第4期17卷 2429-2437页

作者： Liyuan Xiao Xue bai Jingyi Han Tianmi Tang Siyu Chen hui Qi Changmin Hou Fuquan bai Zhenlu Wang Jingqi Guan Institute of Physical Chemistry College of ChemistryJilin UniversityChangchun 130021China The Second Hospital of Jilin University Changchun 130021China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryChangchun 130023China

As a four-electron transfer reaction,oxygen evolution reaction(OER)is limited by large overpotential and slow kinetics.Here,we in-situ synthesized two-dimensional(2D)Ni-Fe metal-organic framework nanosheets on nickel foam(NixFe-TPA/NF,TPA=terephthalic acid)for oxygen evolution in alkaline and alkaline seawater electrolytes.In 1 M KOH,Ni3Fe-TPA/NF shows a low overpotential(η10)of 189 mV at 10 mA·cm^(-2) and an ultra-low overpotential of only 260 mV at 500 mA·cm^(-2).In alkaline seawater,Ni3Fe-TPA/NF still provides impressive OER performance,with anη10 of 265 mV.In-situ Raman characterization results show that the phase transition occurs during the OER,and Ni3FeOOH with more oxygen vacancies is in-situ formed,reducing the OER energy barrier.Density functional theory(DFT)reveals that the synergy between Ni and Fe reduces the energy barrier and accelerates the rate-determining step.In addition,the ultra-thin 2D sheet structure and the close combination of Ni3FeOOH and highly conductive NF support ensure the high catalytic OER activity.Therefore,the surface reconstruction and structural modification strategy can be used to design and prepare high-performance OER electrocatalysts for energy-related applications.

关键词： density functional theory(DFT)calculation Ni3FeOOH oxygen evolution reaction seawater electrolysis surface reconstruction

Psychological interventions for depression in children and adolescents:A bibliometric analysis

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World Journal of Psychiatry 2024年第3期14卷 467-483页

作者： Nan Wang Jia-Qi Kong Nan bai hui-Yue Zhang Min Yin School of Nursing Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND Depression has gradually become a common psychological disorder among children and adolescents.Depression in children and adolescents affects their physical and mental development.Psychotherapy is considered to be one of the main treatment options for depressed children and adolescents.However,our understanding of the global performance and progress of psychological interventions for depression in children and adolescents(PIDCA)research is limited.AIM To identify collaborative research networks in this field and explore the current research status and hotspots through bibliometrics.METHODS Articles and reviews related to PIDCA from January 2010 to April 2023 were identified from the Web of Science Core Collection database.The Charticulator website,CiteSpace and VOSviewer software were used to visualize the trends in publications and citations,the collaborative research networks(countries,institutions,and authors),and the current research status and hotspots.RESULTS Until April 16,2023,1482 publications were identified.The number of documents published each year and citations had increased rapidly in this field.The United States had the highest productivity in this field.The most prolific institution was the University of London.Pim Cuijpers was the most prolific author.In the context of research related to PIDCA,both reference co-citation analysis and keywords co-occurrence analysis identified 10 research hotspots,including thirdwave cognitive behavior therapy,short-term psychoanalytic psychotherapy,cognitive behavioral analysis system of psychotherapy,family element in psychotherapy,modular treatment,mobile-health,emotion-regulation-based transdiagnostic intervention program,dementia risk in later life,predictors of the efficacy of psychological intervention,and risks of psychological intervention.CONCLUSION This bibliometric study provides a comprehensive overview of PIDCA from 2010 to present.Psychological intervention characterized as psychological-process-focused,short,family-involved,modular,inte

关键词： Child Adolescent Depression Psychological intervention Bibliometrics

Primary pancreatic peripheral T-cell lymphoma:A case report

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1668-1675页

作者： Yan-Liang bai Li-Jie Wang hui Luo Ya-Bin Cui Jin-hui Xu hui-Jie Nan Pei-Yao Yang Jun-Wei Niu Ming-Yue Shi Department of Hematology Zhengzhou University People's Hospital and Henan Provincial People's HospitalZhengzhou 450003Henan ProvinceChina Department of Hematology Henan University People's Hospital and Henan Provincial People's HospitalZhengzhou 450003Henan ProvinceChina Department of Radiation Oncology The Affiliated Cancer Hospital of Zhengzhou UniversityZhengzhou 450008Henan ProvinceChina

BACKGROUND Primary pancreatic lymphoma(PPL)is an exceedingly rare tumor with limited mention in scientific literature.The clinical manifestations of PPL are often nonspecific,making it challenging to distinguish this disease from other panc-reatic-related diseases.Chemotherapy remains the primary treatment for these individuals.CASE SUMMARY In this case study,we present the clinical details of a 62-year-old woman who initially presented with vomiting,abdominal pain,and dorsal pain.On further evaluation through positron emission tomography-computed tomography,the patient was considered to have a pancreatic head mass.However,subsequent endoscopic ultrasonography-guided fine needle aspiration(EUS-FNA)revealed that the patient had pancreatic peripheral T-cell lymphoma,not otherwise specified(PTCL-NOS).There was a substantial decrease in the size of the pancreatic mass after the patient underwent a cycle of chemotherapy comprised of brentuximab vedotin,decitabine,and oxaliplatin(brentuximab vedotin and Gemox).The patient had significant improvement in radiological findings at the end of the first cycle.CONCLUSION Primary pancreatic PTCL-NOS is a malignant and heterogeneous lymphoma,in which the clinical manifestations are often nonspecific.It is difficult to diagnose,and the prognosis is poor.Imaging can only be used for auxiliary diagnosis of other diseases.With the help of immunostaining,EUS-FNA could be used to aid in the diagnosis of PPL.After a clear diagnosis,chemotherapy is still the first-line treatment for such patients,and surgical resection is not recommended.A large number of recent studies have shown that the CD30 antibody drug has potential as a therapy for several types of lymphoma.However,identifying new CD30-targeted therapies for different types of lymphoma is urgently needed.In the future,further research on antitumor therapy should be carried out to improve the survival prognosis of such patients.

关键词： Pancreatic cancer Lymphoma Chemotherapy Primary pancreatic lymphoma Case report

Metal-organic framework and its composites modulate macrophage polarization in the treatment of inflammatory diseases

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Chinese Chemical Letters 2024年第5期35卷 45-56页

作者： Feifei Wang Hang Yao Xinyue Wu Yijian Tang Yang bai hui Chong Huan Pang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China School of Pharmacy Changzhou UniversityChangzhou 213164China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing 210023China

Metal-organic framework(MOF)is a periodic sexual network structure with large surface area and high porosity,which is assembled by inorganic nodes and organic ligands through coordinate covalent bond.MOFs have the advantages of controllable pore size and shape,large specific surface area,easy modification and more active sites.In addition,MOF based nanoenzymes display excellent enzyme catalytic activity due to their special structure and multiple exposed metal active sites,controlling the production of reactive oxygen species(ROS)in cells or the body,and thus regulating the polarization of macrophage.This article reviews the mechanism of MOF material regulating macrophage polarization and the function of macrophages with different phenotypes.By utilizing the excellent properties of MOFs and the advantages of combining them with bioactive materials,we have discovered their excellent applications in the treatment of inflammatory diseases.Finally,we discussed the current challenges and prospects faced by MOF based composite materials.We expect that the research in this developing field will play a more important role in combating inflammatory diseases in the field of nanomedicine.

关键词： Metal-organic framework Inflammation Macrophage polarization Reactive oxygen species Nanozyme activity

Rosemary extract improves egg quality by altering gut barrier function,intestinal microbiota and oviductal gene expressions in late-phase laying hens

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Journal of Animal Science and Biotechnology 2024年第1期15卷 295-312页

作者： Lianhua Zhang Junwei Ge Fei Gao Min Yang hui Li Fei Xia Hongtong bai Xiangshu Piao Zhiying Sun Lei Shi Key Laboratory of Plant Resources Institute of BotanyChinese Academy of SciencesBeijing 100093China China National Botanical Garden Beijing 100093China College of Pharmacy Shandong University of Traditional Chinese MedicineJinan 250355China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background Rosemary extract(RE)has been reported to exert antioxidant property.However,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not been systematically studied.This study was investigated to detect the potential effects of RE on performance,egg quality,serum parameters,intestinal heath,cecal microbiota and metabolism,and oviductal gene expressions in late-phase laying hens.A total of 21065-week-old“Jing Tint 6”laying hens were randomly allocated into five treatments with six replicates and seven birds per replicate and fed basal diet(CON)or basal diet supplemented with chlortetracycline at 50 mg/kg(CTC)or RE at 50 mg/kg(RE50),100 mg/kg(RE100),and 200 mg/kg(RE200).Results Our results showed that RE200 improved(P<0.05)Haugh unit and n-6/n-3 of egg yolk,serum superoxide dismutase(SOD)compared with CON.No significant differences were observed for Haugh unit and n-6/n-3 of egg yolk among CTC,RE50,RE100 and RE200 groups.Compared with CTC and RE50 groups,RE200 increased serum SOD activity on d 28 and 56.Compared with CON,RE supplementation decreased(P<0.05)total cholesterol(TC)level.CTC,RE100 and RE200 decreased(P<0.05)serum interleukin-6(IL-6)content compared with CON.CTC and RE200 increased jejunal m RNA expression of ZO-1 and Occludin compared with CON.The biomarkers of cecal microbiota and metabolite induced by RE 200,including Firmicutes,Eisenbergiella,Paraprevotella,Papillibacter,and butyrate,were closely associated with Haugh unit,n-6/n-3,SOD,IL-6,and TC.PICRUSt2 analysis indicated that RE altered carbohydrate and amino acid metabolism of cecal microbiota and increased butyrate synthesizing enzymes,including 3-oxoacid Co A-transferase and butyrate-acetoacetate Co A-transferase.Moreover,transcriptomic analysis revealed that RE200 improved gene expressions and functional pathways related to immunity and albumen formation in the oviductal magnum.Conclusions Dietary supplementation with 200 mg/kg RE could increase egg quality of late-p

关键词： Intestinal health Laying hens Microbiota Oviductal function Phytochemicals Production

Excitonic devices based on two-dimensional transition metal dichalcogenides van der Waals heterostructures

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 41-67页

作者： Yulun Liu Yaojie Zhu Zuowei Yan Ruixue bai Xilin Zhang Yanbo Ren Xiaoyu Cheng hui Ma Chongyun Jiang College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350China School of Physical Science and Technology Tiangong UniversityTianjin 300387China

Excitonic devices are an emerging class of technology that utilizes excitons as carriers for encoding, transmitting, and storing information. Van der Waals heterostructures based on transition metal dichalcogenides often exhibit a type II band alignment, which facilitates the generation of interlayer excitons. As a bonded pair of electrons and holes in the separation layer, interlayer excitons offer the chance to investigate exciton transport due to their intrinsic out-of-plane dipole moment and extended exciton lifetime. Furthermore, interlayer excitons can potentially analyze other encoding strategies for information processing beyond the conventional utilization of spin and charge. The review provided valuable insights and recommendations for researchers studying interlayer excitonic devices within van der Waals heterostructures based on transition metal dichalcogenides. Firstly, we provide an overview of the essential attributes of transition metal dichalcogenide materials, focusing on their fundamental properties, excitonic effects, and the distinctive features exhibited by interlayer excitons in van der Waals heterostructures. Subsequently, this discourse emphasizes the recent advancements in interlayer excitonic devices founded on van der Waals heterostructures, with specific attention is given to the utilization of valley electronics for information processing, employing the valley index. In conclusion, this paper examines the potential and current challenges associated with excitonic devices.

关键词： excitonic devices van der Waals heterostructures transition metal dichalcogenides interlayer excitons valley-Hall effect optoelectronics