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Characterization of human IgM and IgG repertoires in individuals with chronic HIV-1 infection

Virologica Sinica 2022年第3期37卷 370-379页

作者： Xiaolong Tian binbin hong Xiaoyi Zhu Desheng Kong Yumei Wen Yanling Wu Liying Ma Tianlei Ying MOE/NHC Key Laboratory of Medical Molecular Virology School of Basic Medical SciencesShanghai Medical CollegeFudan UniversityShanghai200032China Central Laboratory The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou362000China State Key Laboratory of Infectious Disease Prevention and Control National Center for AIDS/STD Control and PreventionChinese Center for Disease Control and PreventionBeijing102206China Shanghai Engineering Research Center for Synthetic Immunology Shanghai200032China Shanghai Key Laboratory of Lung Inflammation and Injury Shanghai200032China

Advancements in high-throughput sequencing(HTS)of antibody repertoires(Ig-Seq)have unprecedentedly improved our ability to characterize the antibody repertoires on a large scale.However,currently,only a few studies explored the influence of chronic HIV-1 infection on human antibody repertoires and many of them reached contradictory conclusions,possibly limited by inadequate sequencing depth and throughput.To better understand how HIV-1 infection would impact humoral immune system,in this study,we systematically analyzed the differences between the IgM(HIV-IgM)and IgG(HIV-IgG)heavy chain repertoires of HIV-1 infected patients,as well as between antibody repertoires of HIV-1 patients and healthy donors(HH).Notably,the public unique clones accounted for only a negligible proportion between the HIV-IgM and HIV-IgG repertoires libraries,and the diversity of unique clones in HIV-IgG remarkably reduced.In aspect of somatic mutation rates of CDR1 and CDR2,the HIV-IgG repertoire was higher than HIV-IgM.Besides,the average length of CDR3 region in HIV-IgM was significant longer than that in the HH repertoire,presumably caused by the great number of novel VDJ rearrangement patterns,especially a massive use of IGHJ6.Moreover,some of the B cell clonotypes had numerous clones,and somatic variants were detected within the clonotype lineage in HIV-IgG,indicating HIV-1 neutralizing activities.The in-depth characterization of HIV-IgG and HIV-IgM repertoires enriches our knowledge in the profound effect of HIV-1 infection on human antibody repertoires and may have practical value for the discovery of therapeutic antibodies.

关键词： Ig-seq HIV-1 Antibody repertoire VDJ rearrangement Junctional diversity

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Five-channel frequency-division multiplexing using low-loss epsilon-near-zero metamaterial waveguide

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Science China(Physics,Mechanics & Astronomy) 2022年第7期65卷 129-137页

作者： binbin hong Lei Sun Wanlin Wang Yanbing Qiu Naixing Feng Dong Su Nutapong Somjit Ian Robertson Guo Ping Wang Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China The Tenth Research Institute China Electronics Technology Group CorporationChengdu 610036China School of Electronic and Electrical Engineering University of LeedsLeeds LS29JTUK

The rapidly growing global data usage has demanded more efficient ways to utilize the scarce electromagnetic spectrum resource. Recent research has focused on the development of efficient multiplexing techniques in the millimeter-wave band(1-10 mm, or 30-300 GHz) due to the promise of large available bandwidth for future wireless networks. Frequency-division multiplexing is still one of the most commonly-used techniques to maximize the transmission capacity of a wireless network.Based on the frequency-selective tunnelling effect of the low-loss epsilon-near-zero metamaterial waveguide, we numerically and experimentally demonstrate five-channel frequency-division multiplexing and demultiplexing in the millimeter-wave range.We show that this device architecture offers great flexibility to manipulate the filter Q-factors and the transmission spectra of different channels, by changing of the epsilon-near-zero metamaterial waveguide topology and by adding a standard waveguide between two epsilon-near-zero channels. This strategy of frequency-division multiplexing may pave a way for efficiently allocating the spectrum for future communication networks.

关键词： frequency-division multiplexing artificial effective medium epsilon-near-zero metamaterial integrated photonics

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Optical waveguide in curved and welded perovskite nanowires

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Science China(Technological Sciences) 2023年第5期66卷 1471-1479页

作者： ZHANG ZhenYu ZHANG YuPeng hong binbin WANG GuoPing College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060China

Single-crystalline lead halide perovskite nanowires are emerging as promising one-dimensional blocks for nanoscience and nanotechnology,and extensive studies of nano-lasers and nano-photodetectors have been reported.However,as perfect confined structures,their optical waveguide performances have not been widely paid attention to up to now.Here,we report on the such issue on single-crystalline CsPbBr3nanowires and quantify it by near-field optical response mappings.The waveguide is verified as total internal reflection mode at the visible band(532 nm),and its far-field end-facet coupling efficiency of 89.6%and propagation loss as low as 5.9 dB/mm are measured from the nanowire with cross-sectional geometry of~600 nm×300 nm.No evident bending loss exists in naturally curved nanowires,while it usually emerges in artificial-bended ones due to the wrinkled surfaces.Naturally welded nanowire networks show significant advantages in integrated waveguides over the artificial assembled ones,due to the coupled photons at the space-confined end-facet segments.Roughened surface reasoned by lattice degradation is detrimental to propagation loss,but it provides leaked channels for waveguide coupling on nanowire surface.This work studies the optical waveguide performance of perovskite nanowires with different geometries and goes a step further for integrated nanophotonics.

关键词： optical waveguide perovskite nanowires SNOM curved nanowire welded networks

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Mid-infrared waveguiding in three-dimensional microstructured optical waveguides fabricated by femtosecond-laser writing and phosphoric acid etching

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Photonics Research 2020年第3期8卷 257-262页

作者： JINMAN LV binbin hong YANG TAN FENG CHEN JAVIER RODRíGUEZ VáZQUEZ DE ALDANA GUO PING WANG Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518052China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Departamento Fisica Aplicada Facultad CienciasUniversidad de SalamancaSalamanca 37008Spain

We fabricated a three-dimensional microstructured optical waveguide(MOW)in a single-crystal using femtosecond-laser writing and phosphoric acid etching techniques,and observed excellent midinfrared waveguiding performance with low loss of^0.5 d B∕cm.Tracks with a periodic arrangement were written inside the yttrium aluminum garnet(YAG)crystal via femtosecond laser inscription,and then etched by the phosphoric acid(H3 PO4)to form hollow structures.The evolution of the microstructure of tracks was investigated in detail.The function of the MOW was analyzed by different numerical methods,indicating the proposed MOW can effectively operate in quasi-single-mode pattern in the midinfrared wavelength range,which agrees well with our experiment results.

关键词： microstructure laser wave

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False Negative Sample Detection for Graph Contrastive Learning

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Tsinghua Science and Technology 2024年第2期29卷 529-542页

作者： binbin Zhang Li Wang College of Data Science Taiyuan University of TechnologyJinzhong 030600China

Recently,self-supervised learning has shown great potential in Graph Neural Networks (GNNs) through contrastive learning,which aims to learn discriminative features for each node without label information. The key to graph contrastive learning is data augmentation. The anchor node regards its augmented samples as positive samples,and the rest of the samples are regarded as negative samples,some of which may be positive samples. We call these mislabeled samples as “false negative” samples,which will seriously affect the final learning effect. Since such semantically similar samples are ubiquitous in the graph,the problem of false negative samples is very significant. To address this issue,the paper proposes a novel model,False negative sample Detection for Graph Contrastive Learning (FD4GCL),which uses attribute and structure-aware to detect false negative samples. Experimental results on seven datasets show that FD4GCL outperforms the state-of-the-art baselines and even exceeds several supervised methods.

关键词： graph representation learning contrastive learning false negative sample detection

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Perspective for OER electrocatalysts:Lattice engineering of clay-like frameworks with near-surface cluster active sites

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Science China(Technological Sciences) 2024年第1期67卷 330-334页

作者： ZHANG DanTong QIAN binbin XUE DongFeng Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Near-surface cluster active centers(NSCAC)are pivotal functional units in the catalysis of oxygen evolution reaction(OER),which exceeds the limitations imposed by the diverse coordination environments experienced in atomic and molecular active centers,thereby serving as an exceptional medium for exploring the dynamic catalytic processes of metal active sites[1,2].In the OER,the NSCAC primarily consist of the catalytic site and the first neighboring coordinating atoms.The investigation of NSCAC surpasses the exclusive reliance on the electron state regulation mechanism at the atomic level.

关键词： cluster centers exceptional

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Runoff and Infiltration responses of revegetated slopes to clipping management on the northern Loess Plateau

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International Soil and Water Conservation Research 2024年第1期12卷 171-183页

作者： Qilin He binbin Li Fengbao Zhang Nan Shen Mingyi Yang The Research Center of Soil and Water Conservation and Ecological Environment Chinese Academy of Sciences and Ministry of EducationYanglingShaanxi712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYanglingShaanxi712100China Institute of Soil and Water Conservation Northwest A&F UniversityYanglingShaanxi712100China Water and Soil Conservation Monitoring Center of Ministry of Water Resources Beijing100053China University of Chinese Academy of Sciences Beijing100049China

Large-scale vegetation restoration can reduce local watershed water yield,limit vegetation establishment and subsequent growth,and influence regional ecosystem functions.Clipping management by reducing aboveground parts of grassland was gradually recommended and adopted in Grain-for-Green project management to offset these additional issues.Thus,scientific evaluation of the effectiveness of clipping management on infiltration and runoff processes is necessary for maintaining the stability of the surface water system and the sustainability of vegetation restoration in semi-arid regions.A field simulated rainfall experiment was conducted with four managed clipping grasslands(mainly bunge needlegrass and Stipa grandis),including no clipping,light clipping,heavy clipping,and complete clipping under three slope gradients(10,20,and 30°)and three rainfall intensities(60,90,and 120 mm/h)to explore the mechanism of runoff and infiltration responses to clipping using structural equation modeling and variation partitioning based on an SCS-CN model.The results showed the runoff coefficient of the light clipping,heavy clipping,and complete clipping plots were 1.33,2.22,and 4.22 times that of the no clipping plot.The light clipping,heavy clipping,and complete clipping plots decreased the infiltration coefficients by 0%,5%,and 26%relative to the no clipping plot.Rainfall intensity dominated runoff and infiltration amounts,and clipping intensity's total effect was stronger than slope gradient.Clipping intensity and slope gradient were more influential on runoff with increasing rainfall intensity.The mutual inhibition effect was between clipping intensity and slope gradient on runoff.In order to maintain the sustainability of restoration,a 25-50%vegetation coverage after clipping maximizes the benefits of increasing runoff and maintaining enough soil water supply that prevents possible soil drought.We propose that future vegetation restoration policies should evaluate the appropriate clipping intensity;meanwhile,local physiograph

关键词： Runoff Infiltration Grassland clipping management SCS-CN model Structural equation model Variation partitioning

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Transient flameout process of boron-magnesium agglomerates during combustion in oxygen-rich atmospheres

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Particuology 2024年第5期88卷 290-301页

作者： Lian Duan Zhixun Xia Yunchao Feng binbin Chen Likun Ma Jianxin Hu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China School of Mechanical Engineering and Mechanics Xiangtan UniversityXiangtan 411105China

In this study,boron–magnesium agglomerates with varying mass ratios were prepared by drying a micron-sized boron–magnesium mixed suspension,and the combustion process of these agglomerates under different oxygen-rich concentrations were investigated using a laser ignition system.The test results showed that when the mass fraction of magnesium powder in boron-magnesium agglomerates exceeded a certain threshold(between 2%and 5%),flame extinction and reignition occurred after a significant reduction in the agglomerate volume during combustion.This process is referred to as the transient flameout process,which is affected by the magnesium content of the agglomerate and the oxygen concentration in the ambient atmosphere.An increase in the magnesium content or oxygen concentration makes this phenomenon more pronounced.During weakening of the flame intensity,a dark film gradually covered the particle surfaces.X-ray diffraction and elemental analyses of the cross-section and outer surface of the condensed combustion product suggested that the dark film is primarily composed of Mg-B-O ternary oxides.This film prevents direct contact between boron and oxygen,thereby inhibiting surface and gas-phase reactions and leading to the occurrence of the transient flameout phenomenon.

关键词： Agglomerated particle Boron–magnesium fuel Boron combustion Transient flameout process Solid fuel ramjet

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A statistical analysis of the Kappa-type energy spectrum distribution of radiation belt electrons observed by Van Allen Probes

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Earth and Planetary Physics 2024年第2期8卷 368-374页

作者： LuHuai Jiao Xin Ma YuanNong Zhang TaiFeng Jin Song Fu binbin Ni Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation belts.Increased measurements have indicated that the commonly used Maxwellian and Kappa distributions are inadequate for capturing the realistic spectral distributions of radiation belt electrons.Here we adopt the Kappa-type(KT)distribution as the fitting function and perform a statistical analysis to investigate the radiation belt electron flux spectra observed by the Van Allen Probes.By calculating the optimal values of the key KT distribution parameters(i.e.,κandθ2)from the observed spectral shapes,we fit the radiation belt electron fluxes at different L-shells under different geomagnetic conditions.In this manner,we obtain typical values of the KT distribution parameters,which are statistically feasible for modeling the radiation belt electron flux profiles during either geomagnetically quiet or active periods.A comparison of the KT distribution model results with those using the Maxwellian or Kappa distribution reveals the advantage of the KT distribution for studying the overall properties of the radiation belt electron spectral distribution,which has important implications for deepening the current understanding of the radiation belt electron dynamics under evolving geomagnetic conditions.

关键词： radiation belt electron Kappa-type distribution fitting geomagnetic storm

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MSC-YOLO:Improved YOLOv7 Based on Multi-Scale Spatial Context for Small Object Detection in UAV-View

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Computers, Materials & Continua 2024年第4期79卷 983-1003页

作者： Xiangyan Tang Chengchun Ruan Xiulai Li binbin Li Cebin Fu School of Computer Science and Technology Hainan UniversityHaikou570228China Hainan Blockchain Technology Engineering Research Center Hainan UniversityHaikou570228China School of Cyberspace Security(School of Cryptology) Hainan UniversityHaikou570228China

Accurately identifying small objects in high-resolution aerial images presents a complex and crucial task in thefield of small object detection on unmanned aerial vehicles(UAVs).This task is challenging due to variations inUAV flight altitude,differences in object scales,as well as factors like flight speed and motion blur.To enhancethe detection efficacy of small targets in drone aerial imagery,we propose an enhanced You Only Look Onceversion 7(YOLOv7)algorithm based on multi-scale spatial context.We build the MSC-YOLO model,whichincorporates an additional prediction head,denoted as P2,to improve adaptability for small objects.We replaceconventional downsampling with a Spatial-to-Depth Convolutional Combination(CSPDC)module to mitigatethe loss of intricate feature details related to small objects.Furthermore,we propose a Spatial Context Pyramidwith Multi-Scale Attention(SCPMA)module,which captures spatial and channel-dependent features of smalltargets acrossmultiple scales.This module enhances the perception of spatial contextual features and the utilizationof multiscale feature information.On the Visdrone2023 and UAVDT datasets,MSC-YOLO achieves remarkableresults,outperforming the baseline method YOLOv7 by 3.0%in terms ofmean average precision(mAP).The MSCYOLOalgorithm proposed in this paper has demonstrated satisfactory performance in detecting small targets inUAV aerial photography,providing strong support for practical applications.

关键词： Small object detection YOLOv7 multi-scale attention spatial context

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