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Improved Q-learning algorithm for load balance in millimeter wave backhaul networks

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The Journal of China Universities of Posts and Telecommunications 2018年第3期25卷 8-16页

作者： meng Danfeng Li Xiaohui Pu wenjuan State Key Laboratory of Integrated Service Networks Xidian University Collaborative Innovation Center of Information Sensing and Understanding Xidian University

With the intensive deployment of users and the drastic increase of traffic load, a millimeter wave （mmWave） backhaul network was widely investigated. A typical mmWave backhaul network consists of the macro base station （MBS） and the small base stations （SBSs）. How to efficiently associate users with the MBS and the SBSs for load balancing is a key issue in the network. By adding a virtual power bias to the SBSs, more users can access to the SBSs to share the load of the MBS. The bias values shall be set reasonably to guarantee the backhaul efficiency and the quality of service （QoS）. An improved Q-learning algorithm is proposed to effectively adjust the bias value for each SBS. In the proposed algorithm, each SBS becomes an agent with independent learning and can achieve the best behavior, namely the optimal bias value through a series of training. Besides, an improved behavior selection mechanism is adopted to improve the learning efficiency and accelerate the convergence of the algorithm. Finally, simulations conducted in the 60 GHz band demonstrate the superior performance of the proposed algorithm in backhaul efficiency and user outage probability.

关键词： millimeter wave backhaul networks load balance user association Q-learning

GID complex regulates the differentiation of neural stem cells by destabilizing TET2

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Frontiers of Medicine 2023年第6期17卷 1204-1218页

作者： Meiling Xia Rui Yan wenjuan Wang meng Zhang Zhigang Miao Bo Wan Xingshun Xu Department of Neurology The First Afiliated Hospital of Soochow UniversitySuzhou 215006China Institute of Neuroscience Soochow UniversitySuzhou 215006China Jiangsu Key Laboratory of Neuropsychiatric Diseases Soochow UniversitySuzhou 215123China

Brain development requires a delicate balance between self-renewal and differentiation in neural stem cells(NSC),which rely on the precise regulation of gene expression.Ten-eleven translocation 2(TET2)modulates gene expression by the hydroxymethylation of 5-methylcytosine in DNA as an important epigenetic factor and participates in the neuronal differentiation.Yet,the regulation of TET2 in the process of neuronal differentiation remains unknown.Here,the protein level of TET2 was reduced by the ubiquitin-proteasome pathway during NSC differentiation,in contrast to mRNA level.We identified that TET2 physically interacts with the core subunits of the glucose-induced degradation-deficient(GID)ubiquitin ligase complex,an evolutionarily conserved ubiquitin ligase complex and is ubiquitinated by itself.The protein levels of GID complex subunits increased reciprocally with TET2 level upon NSC differentiation.The silencing of the core subunits of the GID complex,including WDR26 and ARMC8,attenuated the ubiquitination and degradation of TET2,increased the global 5-hydroxymethylcytosine levels,and promoted the differentiation of the NSC.TET2 level increased in the brain of the Wdr26^(+/-)mice.Our results illustrated that the GID complex negatively regulates TET2 protein stability,further modulates NSC differentiation,and represents a novel regulatory mechanism involved in brain development.

关键词： TET2 GID complex neural stem cells differentiation of neurons

Recent advances in mitochondria-and lysosomes-targeted small-molecule two-photon fluorescent probes

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Chinese Chemical Letters 2017年第10期28卷 1943-1951页

作者： Peng Ning wenjuan Wang Man Chen Yan Feng Xiangming meng School of Chemistry and Chemical Engineering & Center for Atomic Engineering of Advanced Materials & Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials Anhui University Hefei 230601 China

Mitochondria and lysosomes are essential cellular organelles in most eukaryotic cells by playing the physiological roles to support the normal functions of cells, as well as the life of the whole body. To date,small-molecule fluorescent probes have been considered as one of the vital tools for monitoring and visualizing multiple biological analytes. This review summarized the recent advances in small-molecule two-photon fluorescent probes for metal ions, reactive oxygen species（ROS） and reactive sulfur species（RSS）, and changes inside micro-environment（e.g., p H, viscosity and polarity） in mitochondria and lysosomes, or served as mitotracker and lysotracker with the assistance of two-photon microscopy.

关键词： Two-photon absorption Fluorescent probe Localization Mitochondria Lysosomes

High-Voltage-Gain DC-DC Converter with Three-Winding Coupled Inductor

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Chinese Journal of Electrical Engineering 2019年第1期5卷 10-23页

作者： wenjuan Liang Xuefeng Hu Hao Chen Guiyang Wu meng Zhang Guodong Tan School of Electrical Engineering Anhui University of TechnologyMa’anshan243032 China

A novel DC-DC converter topology that uses a three-winding coupled inductor(TWCI)and a new voltagemultiplication technique is presented for achieving high voltage gain.The proposed converter comprises one boost unit,one passive absorption circuit,and two voltage-multiplier cells.The tertiary winding of the coupled inductor is connected to a capacitor and diode,and this combination acts as a secondary voltage-multiplier cell(SVMC).The SVMC,when combined with two capacitors,the secondary winding of the coupled inductor,a diode,and a switch,forms a primary voltage-multiplier cell,which can achieve a large voltage-conversion ratio that can be adjusted easily.The new voltage-multiplier technique can be used to decrease the number of capacitors and diodes,which improves the transformation efficiency.A prototype circuit with a nominal rating of 300 W is designed to verify the correctness of theoretical analysis.

关键词： Three-winding coupled inductor voltage multiplier output diode stress high step-up

Rice transcription factors OsLBD37/38/39 regulate nitrate uptake by repressing OsNRT2.1/2.2/2.3 under high-nitrogen conditions

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The Crop Journal 2022年第6期10卷 1623-1632页

作者： Xinxin Zhu Dujun Wang Lijuan Xie Tao Zhou Jingyi Zhao Qian Zhang meng Yang wenjuan Wu Xingming Lian National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research(Wuhan) Huazhong Agricultural UniversityWuhan 430070HubeiChina

Nitrate(NO_(3)^(-)) uptake involves a finely regulated and complex multilevel response system.Elucidating the molecular mechanism of nitrate uptake may lead to improving the growth and productivity of plants in the presence of dynamic variation in nitrate concentration.In this study,we identified three lateral organ boundaries domain(LBD)transcription factors,OsLBD37,OsLBD38,and OsLBD39,as regulators of nitrate uptake in response to nitrogen(N)availability.OsLBD37,OsLBD38,and OsLBD39 were induced by ammonium and glutamine in rice roots.Individual or collective knockout of OsLBD37,OsLBD38,and OsLBD39 led to increased concentrations of nitrate and increased expression of OsNRT2.1,OsNRT2.2,and OsNRT2.3respectively under high-N conditions,whereas overexpression of each of these three LBD genes produced opposite effects where N accumulation was reduced.Dual-luciferase reporter assay further confirmed that OsLBD37,OsLBD38,and OsLBD39 possessed transcription inhibitory activities in rice protoplast cells,downregulating the expression of OsNRT2.1/OsNRT2.2/OsNRT2.3.Yeast two-hybrid and bimolecular fluorescence complementation assays showed that OsLBD37 interacted with OsLBD37,OsLBD38,and OsLBD39in the nucleus.Together,these results show that OsLBD37,OsLBD38,and OsLBD39 collaborate to inhibit the expression of OsNRT2.1/OsNRT2.2/OsNRT2.3 transporters under N-sufficient conditions,thereby helping rice plants avoid excessive nitrate accumulation that may affect their growth.

关键词： Oslbd37/Oslbd38/Oslbd39 Transcription factor Nitrate uptake Rice

Semi-Idealized Modeling of Lightning Initiation Related to Vertical Air Motion and Cloud Microphysics

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Journal of Meteorological Research 2017年第5期31卷 976-986页

作者： fei wang yijun zhang dong zheng liangtao xu wenjuan zhang qing meng state key laboratory of severe weather chinese academy of meteorological sciencesBeijing 100081 laboratory of lightning physics and protection engineering chinese academy of meteorological sciencesBeijing 100081

A three-dimensional charge^lischarge numerical model is used, in a semi-idealized mode, to simulate a thunder- storm cell. Characteristics of the granpel microphysics and vertical air motion associated with the lightning initiation are revealed, which could be useful in retrieving charge strength during lightning when no charge^diseharge model is available, The results show that the vertical air motion at the lightning initiation sites （Wini） has a cubic polynomial correlation with the maximum updraft of the storm cell （WceH_m^x）, with the adjusted regression coefficient R2 of ap- proximately 0.97. Meanwhile, the graupel mixing ratio at the lightning initiation sites （qg-ini） has a linear correlation with the maximum graupel mixing ratio of the storm cell （qg-cell-max） and the initiation height （Zini）, with the coeffi- cients being 0.86 and 0.85, respectively. These linear correlations are more significant during the middle and late stages of lightning activity. A zero-charge zone, namely, the area with very low net charge density between the main positive and negative charge layers, appears above the area of qg-oewm and below the upper edge of the granpel re- gion, and is found to be an important area for lightning initiation. Inside the zero-charge zone, large electric intensity forms, and the ratio of qice （ice crystal mixing ratio） to qg （graupel mixing ratio） illustrates an exponential relation- ship to qg-ini. These relationships provide valuable clues to more accurately locating the high-risk area of lightning initiation in thunderstorms when only dual-polarization radar data or outputs from numerical models without char- ging/discharging schemes are available. The results can also help understand the environmental conditions at light- ning initiation sites.

关键词： lightning initiation graupel ice crystal vertical air motion cloud microphysics

Development of fluorine-substituted NH_(2)-biphenyl-diarylpyrimidines as highly potent non-nucleoside reverse transcriptase inhibitors:Boosting the safety and metabolic stability

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Acta Pharmaceutica Sinica B 2023年第3期13卷 1192-1203页

作者： Xin Jin Shuai Wang Limin Zhao wenjuan Huang Yinxiang Zhang Christophe Pannecouque Erik De Clercq Ge meng Huri Piao Fener Chen Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433China Key Laboratory of Natural Resources of Changbai Mountain&Functional Molecules Ministry of EducationCollege of PharmacyYanbian UniversityYanji 133002China Rega Institute for Medical Research KU LeuvenLeuven B-3000Belgium

Our recent studies for nonnucleoside reverse transcriptase inhibitors identified a highly potent compound JK-4b against WT HIV-1(EC_(50)=1.0 nmol/L),but the poor metabolic stability in human liver microsomes(t_(1/2)=14.6 min)and insufficient selectivity(SI=2059)with high cytotoxicity(CC_(50)=2.08μmol/L)remained major issues associated with JK-4b.The present efforts were devoted to the introduction of fluorine into the biphenyl ring of JK-4b,leading to the discovery of a novel series of fluorine-substituted NH_(2)-biphenyl-diarylpyrimidines with noticeable inhibitory activity toward WT HIV-1 strain(EC_(50)=1.8–349 nmol/L).The best compound 5t in this collection(EC_(50)=1.8 nmol/L,CC_(50)=117μmol/L)was 32-fold in selectivity(SI=66,443)compared to JK-4b and showed remarkable potency toward clinically multiple mutant strains,such as L100I,K103N,E138K,and Y181C.The metabolic stability of 5t was also significantly improved(t_(1/2)=74.52 min),approximately 5-fold higher than JK-4b in human liver microsomes(t_(1/2)=14.6 min).Also,5t possessed good stability in both human and monkey plasma.No significant in vitro inhibition effect toward CYP enzyme and hERG was observed.The single-dose acute toxicity test did not induce mice death or obvious pathological damage.These findings pave the way for further development of 5t as a drug candidate.

关键词： HIV-1 NNRTI DAPYs Safety Metabolic stability

A general strategy for bimetallic Pt-based nano-branched structures as highly active and stable oxygen reduction and methanol oxidation bifunctional catalysts

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Nano Research 2020年第3期13卷 638-645页

作者： wenjuan Lei menggang Li Lin He Xun meng Zijie Mu Yongsheng Yu Frances MRoss Weiwei Yang Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun 130103China Ministry of Industry and Information Technology Key Laboratory of Critical Materials Technology for New Energy Conversion and StorageSchool of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Bioelectrochemistry&Environmental Analysis of Gansu Province College cf Chemistry&Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China Department of Materials Science and Engineering Massachusetts Institute cf TechnologyCambridgeMA 02139USA

The morphology and size of Pt-based bimetallic alloys are known to determine their electrocatalytic performance in reactions relevant to fuel cells.Here,we report a general approach for preparing Pt-M(M=Fe,Co and Ni)bimetallic nano-branched structure(NBs)by a simple high temperature solution-phase synthesis.As-prepared Pt-M NBs show a polycrystalline structure and are rich in steps and kinks on the surface,which promote them favorable bifunctional catalytic properties in acidic electrolytes,specifically in terms of the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR).Specially,Pt-Co NBs/C catalyst shows 6.1 and 5.3 times higher in specific activity(SA)and mass activity(MA)for ORR than state-of-the-art commercial Pt/C catalysts,respectively.Moreover,it exhibits a loss of 4.0%in SA and 14.4%in MA after 10,000 cycles of accelerated durability tests(ADTs)compared with the initial activities.In addition,we also confirmed the superior MOR activity of Pt-Co NBs/C catalyst in acidic electrolytes.For Pt-M NBs with other alloying metals,the ORR and MOR activities are both higher than commercial catalysts and are in the sequence of Pt-Co/C>Pt-Fe/C>Pt-Ni/C>commercial Pt/C(or PtRu/C).The improved activities and durability can benefit from the morphological and compositional effects.This synthesis approach may be applied to develop bifunctional catalysts with enhanced ORR and MOR properties for future fuel cells designs.

关键词： Pt-based bimetallic alloy nano-branched structure electrocatalysts,oxygen reduction reaction methanol oxidation reaction

MOF-mediated synthesis of novel PtFeCoNiMn high-entropy nanoalloy as bifunctional oxygen electrocatalysts for zinc-air battery

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Nano Research 2024年第6期17卷 5288-5297页

作者： Mingkuan Xie Xin Xiao Duojie Wu Cheng Zhen Chunsheng Wu wenjuan Wang Hao Nian Fayan Li meng Danny Gu Qiang Xu Shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials(SKLPM) Shenzhen 518055China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech-Kyoto University Advanced Energy Materials Joint Innovation Laboratory(SKAEM-JIL) Shenzhen 518055China Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of Guangdong Southern University of Science and TechnologyShenzhen 518055China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200China

High-entropy alloy(HEA)-based materials are expected to be promising oxygen electrocatalysts due to their exceptional properties.The electronic structure regulation of HEAs plays a pivotal role in enhancing their elctrocatalytic ability.Herein,PtFeCoNiMn nanoparticles(NPs)with subtle lattice distortions are constructed on metal-organic framework-derived nitrogen-doped carbon by an ultra-rapid Joule heating process.Thanks to the modulated electronic structure and the inherent cocktail effect of HEAs,the as-synthesized PtFeCoNiMn/NC exhibits superior bifunctional electrocatalytic performance with a positive half-wave potential of 0.863 V vs.reversible hydrogen electrode(RHE)for oxygen reduction reaction and a low overpotential of 357 mV at 10 mA·cm^(-2)for oxygen evolution reaction.The assembled quasi-solid-state zinc-air battery using PtFeCoNiMn/NC as air electrode shows a high peak power density of 192.16 mW·cm^(-2),low charge−discharge voltage gap,and excellent durability over 500 cycles at 5 mA·cm^(-2).This work demonstrates an effective route for rational design of bifunctional nanostructured HEA electrocatalysts with favorable electronic structures,and opens up a fascinating directions for energy storage and conversion,and beyond.

关键词： oxygen reduction reaction oxygen evolution reaction high-entropy nano-alloy zinc-air battery