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Association analysis of an anti-obesity mechanism and key ripened Pu-erh tea bioactive components by mimicking human general tea drinking

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Food Science and Human Wellness 2024年

作者： junyu liu Zhengyang Song Haihong Chen Wen Zeng Guirong Han Wei Li Bing Xu Yuan Lu Canyang Zhang Zhenglian Xue Bin Lü Chong Zhang Song Yang Yi Wang Xinhui Xing Institute of Biomedical Health Technology and Engineering Shenzhen Bay Laboratory MOE Key Laboratory for Industrial Biocatalysis Centre for Synthetic and Systems Biology Department of Chemical Engineering Tsinghua University Shenzhen International Graduate School Tsinghua University Shandong Province Key Laboratory of Applied Mycology Qingdao International Center on Microbes Utilizing Biogas School of Life Sciences Qingdao Agricultural University Anhui University of Technology Yunnan Shujian Tea Co. Ltd.

Pu-erh tea， a traditional Chinese beverage， performs an anti-obesity function， but the correlation between its components and efficacy remains unknown. Here， we screened two Pu-erh teas with significant anti-obesity efficacies from 11 teas. In vitro experiments revealed that lipid accumulation in L02 cells and lipid synthesis in 3T3-L1 cells were significantly better inhibited by Tea-B than Tea-A. Further in vivo experiments using model mice revealed that the differences in chemical components generated two pathways in the anti-obesity efficacy and mechanism of Pu-erh teas. Tea-A changes the histomorphology of brown adipose tissue (BAT) and increases the abundance of Coriobacteriaceae＿UCG＿002 and cyclic AMP in guts through high chemical contents of cyclopentasiloxane， decamethyl， tridecane and 1，2，3-trimethoxybenzene， eventually increasing BAT activation and fat browning gene expression; the high content of hexadecane and 1，2-dimethoxy-benzene in Tea-B reduces white adipose tissue (WAT) accumulation and the process of fatty liver， increases the abundance of Odoribacter and sphinganine 1-phosphate， inhibits the expression of lipid synthesis and transport genes. These mechanistic findings on the association of the representative bioactive components in Pu-erh teas with the anti-obesity phenotypes， gut microbes， gut metabolite structure and anti-obesity pathways， which were obtained for the first time， provide foundations for developing functional Pu-erh tea.

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Attention-Enhanced Voice Portrait Model Using Generative Adversarial Network

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Computers, Materials & Continua 2024年第4期79卷 837-855页

作者： Jingyi Mao Yuchen Zhou YifanWang junyu Li Ziqing liu Fanliang Bu School of Information Network Security People’s Public Security University of ChinaBeijing100038China

Voice portrait technology has explored and established the relationship between speakers’ voices and their facialfeatures, aiming to generate corresponding facial characteristics by providing the voice of an unknown speaker.Due to its powerful advantages in image generation, Generative Adversarial Networks (GANs) have now beenwidely applied across various fields. The existing Voice2Face methods for voice portraits are primarily based onGANs trained on voice-face paired datasets. However, voice portrait models solely constructed on GANs facelimitations in image generation quality and struggle to maintain facial similarity. Additionally, the training processis relatively unstable, thereby affecting the overall generative performance of the model. To overcome the abovechallenges,wepropose a novel deepGenerativeAdversarialNetworkmodel for audio-visual synthesis, namedAVPGAN(Attention-enhanced Voice Portrait Model using Generative Adversarial Network). This model is based ona convolutional attention mechanism and is capable of generating corresponding facial images from the voice ofan unknown speaker. Firstly, to address the issue of training instability, we integrate convolutional neural networkswith deep GANs. In the network architecture, we apply spectral normalization to constrain the variation of thediscriminator, preventing issues such as mode collapse. Secondly, to enhance the model’s ability to extract relevantfeatures between the two modalities, we propose a voice portrait model based on convolutional attention. Thismodel learns the mapping relationship between voice and facial features in a common space from both channeland spatial dimensions independently. Thirdly, to enhance the quality of generated faces, we have incorporated adegradation removal module and utilized pretrained facial GANs as facial priors to repair and enhance the clarityof the generated facial images. Experimental results demonstrate that our AVP-GAN achieved a cosine similarity of0.511, outperforming the performance of our comparison mo

关键词： Cross-modal generation GANs voice portrait technology face synthesis

Inhibition of Defect-Induced Ice Nucleation, Propagation, and Adhesion by Bioinspired Self-Healing Anti-Icing Coatings

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Research 2024年第1期2023卷 237-246页

作者： Shu Tian Ruiqi Li Xinmeng liu Jiancheng Wang junyu Yu Sijia Xu Yunqing Tian Jing Yang Lei Zhang Department of Biochemical Engineering Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(MOE)School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou CityShandong Province 256606China

Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing cycles.Herein,the mechanisms of surface-defect-induced icing are clarified.At the defects,water molecules exhibit stronger adsorption and the heat transfer rate increases,accelerating the condensation of water vapor as well as ice nucleation and propagation.Moreover,the ice–defect interlocking structure increases the ice adhesion strength.Thus,a self-healing(at−20℃)antifreeze-protein(AFP)-inspired anti-icing coating is developed.The coating is based on a design that mimics the ice-binding and non-ice-binding sites in AFPs.It enables the coating to markedly inhibit ice nucleation(nucleation temperature<−29.4℃),prevent ice propagation(propagation rate<0.00048 cm^(2)/s),and reduce ice adhesion on the surface(adhesion strength<38.9 kPa).More importantly,the coating can also autonomously self-heal at−20℃,as a result of multiple dynamic bonds in its structure,to inhibit defect-induced icing processes.The healed coating sustains high anti-icing and deicing performance even under various extreme conditions.This work reveals the in-depth mechanism of defect-induced ice formation as well as adhesion,and proposes a self-healing anti-icing coating for outdoor infrastructures.

关键词： coating defect clarified

Analysis of RNA Recognition and Binding Characteristics of OsCPPR1 Protein in Rice

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Rice science 2024年第2期31卷 215-225,I0032-I0035页

作者： ZHENG Shaoyan CHEN junyu LI Huatian liu Zhenlan LI Jing ZHUANG Chuxiong State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Guangdong Laboratory for Lingnan Modern Agriculture/College of Life Sciences South China Agricultural UniversityGuangzhou 510642China

Pentatricopeptide repeat(PPR)proteins represent one of the largest protein families in plants and typically localize to organelles like mitochondria and chloroplasts.By contrast,CYTOPLASMLOCALIZED PPR1(OsCPPR1)is a cytoplasm-localized PPR protein that can degrade OsGOLDENLIKE1(OsGLK1)mRNA in the tapetum of rice anther.However,the mechanism,by which OsCPPR1 recognizes and binds to OsGLK1 transcripts,remains unknown.Through protein structure prediction and macromolecular docking experiments,we observed that distinct PPR motif structures of OsCPPR1 exhibited varying binding efficiencies to OsGLK1 RNA.Moreover,RNA-electrophoretic mobility shift assay experiment demonstrated that the recombinant OsCPPR1 can directly recognize and bind to OsGLK1 mRNA in vitro.This further confirmed that the mutations in the conserved amino acids in each PPR motif resulted in loss of activity,while truncation of OsCPPR1 decreased its binding efficiency.These findings collectively suggest that it may require some co-factors to assist in cleavage,a facet that warrants further exploration in subsequent studies.

关键词： OsCPPR1 RNA recognition and binding pentatricopeptide repeat rice

Energy-efficient UAV-NOMA aided wireless coverage with massive connections

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Science China(Information Sciences) 2023年第12期66卷 194-208页

作者： Yuqiao TONG Min SHENG junyu liu Nan ZHAO School of Information and Communication Engineering Dalian University of Technology State Key Laboratory of Integrated Services Networks Xidian University

In this paper, we propose an unmanned aerial vehicle(UAV)-assisted wireless coverage scheme,wherein UAVs help to serve the cell-edge users for ground base stations based on non-orthogonal multiple access(NOMA). The combined benefits of wide coverage and massive connections enable UAV-NOMA-aided wireless coverage to effectively meet the requirements of the Internet of Everything. Meanwhile, energy efficiency(EE) is maximized via resource allocation to address the issue of the power supply bottleneck of UAVs. The non-convex optimization problem is transformed into two convex subproblems of trajectory optimization and power allocation, and an iterative alternating optimization algorithm is proposed to address it effectively. Moreover, we further considered the energy consumption of the ground base stations, effectively minimizing it by optimizing precoding while guaranteeing average throughput. Numerical results verify the effectiveness of the proposed UAV-aided wireless coverage scheme and demonstrate the EE improvement.

关键词： energy efficiency non-orthogonal multiple access trajectory optimization unmanned aerial vehicle wireless coverage

6G Service Coverage with Mega Satellite Constellations

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China Communications 2022年第1期19卷 64-76页

作者： Min Sheng Di Zhou Weigang Bai junyu liu Jiandong Li State Key Laboratory of Integrated Service Networks Xidian UniversityXi’anShaanxi710071China

The rapid development and continuous updating of the mega satellite constellation(MSC)have brought new visions for the future 6G coverage extension, where the global seamless signal coverage can realize ubiquitous services for user terminals. However, global traffic demands present nonuniform characteristics. Therefore, how to ensure the on-demand service coverage for the specific traffic demand, i.e., the ratio of traffic density to service requirement per unit area, is the core issue of 6G wireless coverage extension exploiting the MSC. To this regard, this paper first discusses the open challenges to reveal the future direction of 6G wireless coverage extension from the perspective of key factors affecting service coverage performance, i.e., the network access capacity, space segment capacity and their matchingrelationship. Furthermore, we elaborate on the key factors affecting effective matchings of the aforementioned aspects, thereby improving service coverage capability.

关键词： 6G mega satellite constellations on-demand service coverage un-uniform traffic demands resource management

An improved typhoon monitoring model based on precipitable water vapor and pressure

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Geodesy and Geodynamics 2024年第3期15卷 276-290页

作者： junyu Li Haojie Li Lilong liu Jiaqing Chen Yibin Yao Mingyun Hu Liangke Huang Fade Chen Tengxu Zhang Lv Zhou College of Geomatics and Geoinformation Guilin University of TechnologyGuilin 541006China Guangxi Key Laboratory of Spatial Information and Geomatics Guilin 541006China Qinzhou Institute of Surveying and Mapping for Housing and Urban-Rural Development Co. Ltd.Qinzhou 535000China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China School of Resources and Environmental Science and Engineering Hubei University of Science and TechnologyXianning 437100China

The potential of monitoring the movement of typhoons using the precipitable water vapor(PWV) has been confirmed. However, monitoring the movement of typhoon is focused on PWV, making it difficult to describe the movement of a typhoon in detail minutely and resulting in insufficient accuracy. Hence,based on PWV and meteorological data, we propose an improved typhoon monitoring mode. First, the European Centre for Medium-Range Weather Forecasts Reanalysis 5-derived PWV(ERA5-PWV) and the Global Navigation Satellite System-derived PWV(GNSS-PWV) were compared with the reference radiosonde PWV(RS-PWV). Then, using the PWV and atmospheric parameters derived from ERA5, we discussed the anomalous variations of PWV, pressure(P), precipitation, and wind speed during different typhoons. Finally, we compiled a list of critical factors related to typhoon movement, PWV and P. We developed an improved multi-factor typhoon monitoring mode(IMTM) with different models(i.e.,IMTM-I and IMTM-II) in different cases with a higher density of GNSS observation or only Numerical Weather Prediction(NWP) data. The IMTM was evaluated through the reference movement speeds of HATO and Mangkhut from the China Meteorological Observatory Typhoon Network(CMOTN). The results show that the root mean square(RMS) of the IMTM-I is 1.26 km/h based on ERA5-P and ERA5-PWV,and the absolute bias values are mostly within 2 km/h. Compared with the models considering the single factor ERA5-P/ERA5-PWV, the RMS of the IMTM-I is improved by 26.3% and 38.5%, respectively. The IMTM-II model manifests a residual of only 0.35 km/h. Compared with the single-factor model based on GNSS-PWV/P, the residual of the IMTM-II model is reduced by 90.8% and 84.1%, respectively. These results propose that the typhoon movement monitoring approach combining PWV and P has evident advantages over the single-factor model and is expected to supplement traditional typhoon monitoring.

关键词： Typhoon GNSS/ERA5 PWV Pressure Monitoring Improved model

Enabling Efficient Caching in High Mobility UAV Communications Network under Limited Backhaul

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China Communications 2022年第10期19卷 207-219页

作者： Yan Wu Jiandong Li junyu liu Min Sheng Chenxi Zhao State Key Laboratory of Integrated Service Networks Xidian UniversityXi'anShaanxi 710071China

Due to flexible deployment,unmanned aerial vehicle(UAV)mounted aerial access points are capable of expanding the coverage capabilities of existing terrestrial base stations(TBSs).Different from TBSs,however,UAV access points(UAPs)are of high mobility in horizontal and vertical dimensions,which may deteriorate the coverage performance.Worsestill,the mobility of UAPs would as well increase the pressure of wireless backhaul.In this light,we investigate the performance of the cache-enabled UAV communications network(CUCN)in terms of network spatial throughput(ST)by analyzing the line of sight(LoS)connections and non-line of sight(NLoS)connections.It is found that the network ST is exponentially decreased with the square of UAP altitude.Furthermore,contrary to intuition,a large cache size may deteriorate the network ST when UAPs are over-deployed.The reason is that a large cache size increases the hit probability,which may increase the activation of UAPs and consequently result in complicated interference.Aiming to maximize the network ST,we optimize the cache strategy under limited backhaul.Remarkably,the results show that network ST could be substantially improved by the optimized cache strategy and the performance degeneration brought by UAP high mobility could be even eliminated especially when the UAP altitude is high.

关键词： caching optimization UAV communications network spatial throughput stochastic geometry aerial access point

Spectrum-Efficient User Association in Caching Enabled Dense Small Cell Network

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China Communications 2023年第3期20卷 86-104页

作者： junyu liu Min Sheng Xiaona Zhao Shuang Ni Jiandong Li State Key Laboratory of ISN Xidian UniversityXi’an 710071China Department of Broadband Communication Peng Cheng LaboratoryShenzhen 518055China

In this paper,we reveal the fundamental limitation of network densification on the performance of caching enabled small cell network(CSCN)under two typical user association rules,namely,contentand distance-based rules.It indicates that immoderately caching content would significantly change the interference distribution in CSCN,which may degrade the network area spectral efficiency(ASE).Meanwhile,it is shown that content-based rule outperforms the distance-based rule in terms of network ASE only when small cell base stations(BSs)are sparsely deployed with low decoding thresholds.Moreover,it is proved that network ASE under distance-based user association serves as the upper bound of that under content-based rule in dense BS regime.To enable more spectrum-efficient user association in dense CSCN,we further optimize network ASE by designing a probabilistic content retrieving strategy based on distance-based rule.With the optimized retrieving probability,network ASE could be substantially enhanced and even increase with the growing BS density in dense BS regime.

关键词： caching dense network user association