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Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

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Digital Communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai Huan Li Xiao Tang ruonan Zhang Haotong Cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of Computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum *** tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded *** fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent *** tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV ***,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation *** further propose an iterative power allocation algorithm based on the sequential convex approximation *** simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management

Potential evaluation and implementation strategy for pocket park construction in high-density urban areas: A case study in Dalian, China

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Frontiers of Architectural Research 2024年第2期13卷 319-334页

作者： Jing Dong ruonan Guo Fei Guo Jun Cai School of Architecture and Fine Art Dalian University of TechnologyDalian 116024China

As an important element of urban renewal in highly urbanized areas, pocket parks with small size, flexible layout and daily accessibility are becoming a major component of green infrastructure and the mainstay of outdoor recreation space expansion in high-density urban centers. Nevertheless, the absence of a comprehensive framework for evaluating the potential of pocket park construction (PPC), one that integrates diverse influencing factors on a macro scale, has resulted in the random installation of such spaces, often failing to optimize the utilization of urban land. Addressing this critical lacuna, we propose an approach to evaluate PPC potential from a city-scale perspective, which is used to support the determination of which land units should be prioritized for PPC. A complete and feasible workflow was also established to identify potential land units, construct an index system for PPC combining demand and supply levels, quantitatively calculate indices based on remote sensing (RS) and geographic information system (GIS), accurately evaluate PPC potential using an entropy-weighted TOPSIS model, and develop targeted renewal strategies. A case study in Dalian, China, demonstrated the applicability and implications of the workflow. The results showed that it is flexible and easy to adapt to different local contexts, allowing evaluators to introduce parameters considering the availability of local data, and will help decision makers to build pocket parks in the most effective plots, providing a strong reference for high-quality development in other high-density urban centers facing the contradiction between ecological construction and land scarcity.

关键词： Pocket park Potential evaluation Urban renewal High-density urban areas

Syntheses of new di-nuclear and tetra-nuclear lanthanide 9-anthracenecarboxylates:Magnetocaloric effect,slow magnetic relaxation and luminescent properties

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Journal of Rare Earths 2024年第6期42卷 1101-1109,I0004页

作者： Xing Liu ruonan Yang Lu Zhang Jian Zhou Chunmei Huang Huahong Zou Zunhong Xiao Chongqing Key Laboratory of Inorganic Functional Materials College of ChemistryChongqing Normal UniversityChongqing401331China Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources(ministry of Education of China) School of Chemistry and Chemical Engineering of Guangxi Normal UniversityGuilin541004China School of Chemistry and Materials Guizhou Normal UniversityGuiyang550025China

Lanthanide complex-based materials with magnetic and luminescent properties have received a great deal of attention,owing to their importantly potential applications in diverse *** this work,the 9-anthracenecarboxylic acid(9-Haca)as bridging ligand was applied in combination with optically activeπ-conjugated 2,4,6-tri(2-pyridyl)-1,3,5-triazine(tptz)to construct a series of new di-nuclear and tetranuclear lanthanide 9-anthracenecarboxylates[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]·0.25H_(2)O(1),[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]·0.5AQ·CH_(3)COOH_(2)H_(2)O[Ln=Sm(2a),Eu(2b),Gd(2c),Tb(2d),Dy(2e),Tm(2f);AQ=9,10-anthracenedione]and[Ln_(4)(9-aca)_(10)(tptz)_(2)(CH3COO)2]·H_(2)O[Ln=Eu(3a),Gd(3b),Dy(3c)].1 displays a di-nuclear centrosymmetric moiety[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]built up from two complex[La(9-aca)_(2)(tptz)]groups bridged by one H_(2)O molecule and two syn-syn-μ2-η1:η1-9-aca-bridging ligands,while 2a-2f are isostructural and co mprise another di-nuclear centrosymmetric moieties[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]based on two complex[Ln(9-aca)_(2)(tptz)(H_(2)O)]groups connected by two syn-syn-μ2-η1:η1-9-aca-bridging ligands,3a-3c are isostructural and show tetra-nuclear centro symmetric moieties[Ln4(9-aca)10(tptz)2(CH3COO)2]containing three types of coordination modes of *** present compounds offer the only examples of lanthanide 9-anthracenecarboxylates decorated by optically active *** investigations of 2a,2c-2f,and 3b-3c indicate that 3c is typical of slow relaxation of the magnetization,while 2c and 3b show significant magnetocaloric effect(MCE)with the value of-ΔSm of 5.26 J/(kg·K)at 4 K and 15.65 J/(kg·K)at 2 K(ΔH=7 T),*** luminescent properties were also studied and reveal that the characteristic luminescent properties of the 7r-conjugated aromatic ligands are introduced into magnetic lanthanide 9-anthracenecarboxylates,simultaneously exhibiting slow magnetic relaxation(or MCE)and luminescen

关键词： Lanthanide complexes Luminescence Magnetic properties Magnetocaloric effect Slow magnetic relaxation Rare earths

Microbial phenolic metabolites 3-(3',4'-dihydroxyphenyl)propanoic acid and 3',4'-dihydroxyphenylacetic acid prevent obesity in mice fed high-fat diet

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Food Science and Human Wellness 2024年第1期13卷 327-338页

作者： Wanbing Chen ruonan Liu Xiaoling Zhu Qun Lu Hong Yang Rui Liu College of Food Science and Technology Huazhong Agricultural UniversityWuhan 430000China Key Laboratory of Environment Correlative Dietology(Huazhong Agricultural University) Ministry of educationWuhan 430000China Wuhan Engineering Research Center of Bee Products on Quality and Safety Control Wuhan 430000China Key Laboratory of Urban Agriculture in Central China Ministry of Agriculture and Rural AffairsWuhan 430000China Hubei Provincial Institute for Food Supervision and Test Wuhan 430070China

Obesity is associated with numerous metabolic disorders,and dietary polyphenols have been confirmed to have beneficial effects on the metabolism in ***,the effect of 3-(3’,4’-dihydroxyphenyl)propanoic acid(DHPA)and 3’,4’-dihydroxyphenylacetic acid(DHAA),two main metabolites of dietary polyphenols,on obesity remains poorly *** this study,DHPA and DHAA were found to alleviate obesity,as well as regulate insulin resistance,lipid metabolism,and oxidative stress response in high-fat diet(HFD)***,the 16S rRNA sequencing and UHPLC-Q-TOF/MS demonstrated that DHPA and DHAA only slightly disturbed the intestinal microbiome,but significantly altered the urine metabolome of HFD mice mainly by regulating pentose and glucuronate interconversion,tyrosine metabolism,pentose phosphate and tricarboxylic acid(TCA)cycle as indicated by metabolic pathway analysis based on Kyoto Encyclopedia of Genes and Genomes(KEGG)*** analysis revealed that the differential metabolites are strongly associated with body weight,blood glucose,insulin level,and superoxide dismutase(SOD)enzyme *** results revealed that DHPA and DHAA exert their anti-obesity effect by regulating important metabolites in the glucose,lipid and tyrosine metabolism pathways.

关键词： Obesity Dietary polyphenol metabolites Gut microbiota Metabonomics

The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model

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Food Science and Human Wellness 2024年第2期13卷 748-764页

作者： ruonan Yan Chi-Tang Ho Yanan Liu Shengnan Zhan Zufang Wu Xin Zhang Department of Food Science and Engineering Ningbo UniversityNingbo 315211China Department of Food Science Rutgers UniversityNew BrunswickNew Jersey 08901USA

The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host *** present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state *** fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic *** results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health.

关键词： Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism

Pd cluster decorated free standing flexible cathode for high performance Li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： Liang Guo Guoliang Zhang ruonan Yang Dongmei Zhang Xiuqi Zhang Han Yu Xia Li Feng Dang Key Laboratory for Liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for Li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

Gradient layered MXene/Fe_(3)O_(4)@CNTs/TOCNF ultrathin nanocomposite paper exhibiting effective electromagnetic shielding and multifunctionality

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Nano Research 2024年第9期17卷 8233-8242页

作者： Zhengkun Ma Jingzong He Shilin Liu Xiaoxuan Qie Meiheng Gan ruonan Cheng Qilin Wu Malcolm Xing State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China Department of Mechanical Engineering University of ManitobaWinnipegMB R3T 2N2Canada

As wearable electronic devices are rapidly developing,there is an urgent need for lightweight,flexible,and ultrathin multifunctional electromagnetic interference(EMI)shielding ***,the flexible ultrathin paper that combines efficient shielding and multifunctional integration remains a considerable ***,a novel MXene/Fe_(3)O_(4)@CNTs/TOCNF(MCT,MXene=transition metal carbide/carbonitride,CNTs=carbon nanotubes,TOCNF=TEMPO-oxidized cellulose nanofiber,TEMPO=2,2,6,6-tetramethylpiperidine-1-oxyl radical)nanocomposite paper with a multilayer electromagnetic gradient structure and electromagnetic dual losses was successfully prepared by a simple filtration *** from effective gradient design and adjusting the proportion of TOCNF,the composite paper(only 18μm)exhibits outstanding shielding effectiveness(SE)of 66 dB in the X-band,ultrahigh thickness-specific SE and surface-specific SE values of 3300 dB·mm-1 and 31,428 dB·cm^(2)·g^(-1)***,dehydroxylation treatment improves MCT paper's hydrophobicity,environmental stability,and mechanical strength,expanding its range of ***,the highly efficient Joule heating properties and hydrophobicity provide MCT additional de-icing *** also simulated the electromagnetic shielding effects of MCT composite paper,which was applied in *** study documents an innovative and intriguing material combination,providing a simple and effective manufacturing strategy for developing EMI shielding *** paper is highly suitable for outdoor portable or wearable electronic devices and has significant application potential in humid/severe cold environments.

关键词： cellulose fiber thin papers nanocomposites electromagnetic interference(EMI)shielding

TBBPA rather than its main derivatives enhanced growth of endometrial cancer via p53 ubiquitination

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Journal of Environmental Sciences 2024年第3期137卷 82-95页

作者： Hongyan Yu Jingxu Zhang Jing Liu ruonan Pan Yu Wang Xiaoting Jin Rifat Zubair Ahmed Yuxin Zheng Department of Occupational Health and Environmental Health School of Public HealthQingdao UniversityQingdao 266071China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Genetics University of KarachiKarachi 75270Pakistan

Tetrabromobisphenol A(TBBPA)and its derivatives widely exist in various environments and *** the available data indicate that TBBPA exposure is highly associated with the increased incidence of endometrial cancer(EC),the effects of TBBPA and its main derivatives on EC proliferation and the involved crucial mechanism remain *** present study aimed to investigate the effects of TBBPA and its derivatives under environmental concentrations on the proliferation of EC,and the crucial mechanism on the progression of EC caused by bromine fame retardants *** this research,TBBPA and two of the most common TBBPA derivatives including TBBPA bis(2-hydroxyethyl ether)(TBBPABHEE)and TBBPA bis(dibromopropyl ether)(TBBPA-BDBPE)were screened for their capacities in induced EC proliferation and explored the related mechanism by in vitro cell culture model and in vivo mice *** environmental concentrations,TBBPA promoted the proliferation of EC,the main derivatives of TBBPA(TBBPA-BHEE and TBBPA-BDBPE)did not present the similar facilitation *** ubiquitination degradation of p53 was crucial in TBBPA induced EC proliferation,which resulted in the increase of downstream cell cycle and decrease of *** further molecular docking result suggested the high affinity between TBBPA and ubiquitinated *** finding revealed the effects of TBBPA and its derivatives on EC proliferation,thus providing novel insights into the underlying mechanisms of TBBPA-caused EC.

关键词： Tetrabromobisphenol A(TBBPA) Endometrial cancer(EC) Derivatives Ubiquitin proteases p53

Effects of long-term partial substitution of inorganic fertilizer with pig manure and/or straw on nitrogen fractions and microbiological properties in greenhouse vegetable soils

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Journal of Integrative Agriculture 2024年第6期23卷 2083-2098页

作者： Shuo Yuan ruonan Li Yinjie Zhang Hao'an Luan Jiwei Tang Liying Wang Hongjie Ji Shaowen Huang State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China Institute of Agricultural Resources and Environment Hebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051China College of Resources and Environment Henan Agricultural UniversityZhengzhou 450002China College of Forestry Hebei Agricultural UniversityBaoding 071000China

Partial substitution of inorganic fertilizers with organic amendments is an important agricultural management *** 11-year field experiment(22 cropping periods)was carried out to analyze the impacts of different partial substitution treatments on crop yields and the transformation of nitrogen fractions in greenhouse vegetable *** treatments with equal N,P_(2)O_(5),and K_(2)O inputs were selected,including complete inorganic fertilizer N(CN),50%inorganic fertilizer N plus 50%pig manure N(CPN),50%inorganic fertilizer N plus 25%pig manure N and 25%corn straw N(CPSN),and 50%inorganic fertilizer N plus 50%corn straw N(CSN).Organic substitution treatments tended to increase crop yields since the 6th cropping period compared to the CN *** the 8th to the 22nd cropping periods,the highest yields were observed in the CPSN treatment where yields were 7.5-11.1%greater than in CN *** 11-year fertilization,compared to CN,organic substitution treatments significantly increased the concentrations of NO_(3)^(-)-N,NH_(4)^(+)-N,acid hydrolysis ammonium-N(AHAN),amino acid-N(AAN),amino sugar-N(ASN),and acid hydrolysis unknown-N(AHUN)in soil by 45.0-69.4,32.8-58.1,49.3-66.6,62.0-69.5,34.5-100.3,and 109.2-172.9%,*** analysis indicated that soil C/N and OC concentration significantly affected the distribution of N *** highest concentrations of NO_(3)^(-)-N,AHAN,AAN,AHUN were found in the CPSN *** substitution treatments increased the activities ofβ-glucosidase,β-cellobiosidase,N-acetyl-glucosamidase,L-aminopeptidase,and phosphatase in the *** substitution treatments reduced vector length and increased vector angle,indicating alleviation of constraints of C and N on soil *** substitution treatments increased the total concentrations of phospholipid fatty acids(PLFAs)in the soil by 109.9-205.3%,and increased the relative abundance of G^(+)bacteria and fungi taxa,but decreased the relat

关键词： organic substitution management greenhouse vegetable production N fractions microbial community composition extracellular enzyme activity enzyme stoichiometry coefficients