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SGT-Net: A Transformer-Based Stratified Graph Convolutional Network for 3D Point Cloud Semantic Segmentation

Computers, Materials & Continua 2024年第6期79卷 4471-4489页

作者： Suyi Liu Jianning Chi Chengdong wu fang Xu Xiaosheng Yu Faculty of Robot Science and Engineering Northeastern UniversityShenyang110167China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China SIASUN Robot&Automation Co. Ltd.Shenyang110169China

In recent years,semantic segmentation on 3D point cloud data has attracted much *** 2D images where pixels distribute regularly in the image domain,3D point clouds in non-Euclidean space are irregular and inherently ***,it is very difficult to extract long-range contexts and effectively aggregate local features for semantic segmentation in 3D point cloud *** current methods either focus on local feature aggregation or long-range context dependency,but fail to directly establish a global-local feature extractor to complete the point cloud semantic segmentation *** this paper,we propose a Transformer-based stratified graph convolutional network(SGT-Net),which enlarges the effective receptive field and builds direct long-range ***,we first propose a novel dense-sparse sampling strategy that provides dense local vertices and sparse long-distance vertices for subsequent graph convolutional network(GCN).Secondly,we propose a multi-key self-attention mechanism based on the Transformer to further weight augmentation for crucial neighboring relationships and enlarge the effective receptive *** addition,to further improve the efficiency of the network,we propose a similarity measurement module to determine whether the neighborhood near the center point is *** demonstrate the validity and superiority of our method on the S3DIS and ShapeNet *** ablation experiments and segmentation visualization,we verify that the SGT model can improve the performance of the point cloud semantic segmentation.

关键词： 3D point cloud semantic segmentation long-range contexts global-local feature graph convolutional network dense-sparse sampling strategy

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Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： ZHAO Tao shi Yan LU Kun XI Xiang wu XueZhong XIAO DingBang College of Intelligence Science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

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Antibacterial activity and mechanism of X33 antimicrobial oligopeptide against Acinetobacter baumannii

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Synthetic and Systems Biotechnology 2024年第2期9卷 312-321页

作者： Qunlin Lu Xiaoyu wu Yuan fang Yuanxiu Wang Bin Zhang College of Bioscience and Bioengineering Jiangxi Agriculture UniversityNanchang330045China Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources Nanchang330045China Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables in Jiangxi Province Nanchang330045China

Acinetobacter baumannii is a pathogenic bacterium widespread in human environments,especially in intensive care units,and is associated with high morbidity and infection *** drug resistance in *** frequently leads to the death of patients,making the development of multi-effect antibacterial agents against this bacterium a research *** have previously found that the X33 antimicrobial oligopeptide can effectively inhibit the growth of Penicillium digitatum and Candida ***,we evaluated the antibacterial activity of X33 antimicrobial oligopeptide against *** by determining the minimum inhibitory concentration,inhibition zone,and growth *** increase in extracellular alkaline phosphatase and the leakage of intracellular compounds confirmed the effect of X33 antimicrobial oligopeptide on the cell wall and *** in reactive oxygen species,malondialdehyde,ATP,reducing sugar,soluble protein,and pyruvate content demonstrated that the incubation with X33 antimicrobial oligopeptide affected energy metabolism and oxidative *** with the physiological characteristics,transcriptomics analysis indicated that incubation with X33 antimicrobial oligopeptide significantly induced changes in the expression of 2339 genes,including 1262 upregulated and 1077 downregulated genes,which participate in oxidative phosphorylation,ribosome,quorum sensing,fatty acid degradation,glycolysis/gluconeogenesis,and citrate cycle *** results provide a fundamental basis for investigating the mechanism of X33 antimicrobial oligopeptide as a potential drug against ***.

关键词： Acinetobacter baumannii Antimicrobial agents Antibiotic resistance Hospital-acquired infections

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SO_(2)-Insertion induced enantioselective oxysulfonylation to access β-chiral sulfones with quaternary carbon stereocenters

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Science China Chemistry 2024年第3期67卷 908-913页

作者： Jun Zhang Xuefeng Wang Peiqi Wang Jiayuan fang Shaoyu Li Jie wu School of Pharmaceutical and Chemical Engineering&Institute for Advanced Studies Taizhou UniversityShanghai 200438China Department of Chemistry Fudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

β-Chiral sulfones are structural motifs widely found in natural products and bioactive molecules, while also serving as important intermediates for the synthesis of valuable chiral scaffolds. In contrast to the rapid growth of sulfur dioxide insertion chemistry over the last decade, enantioselective catalytic variants for accessing β-chiral sulfones, especially those bearing a quaternary carbon stereocenter, remain rare. Herein, we report an enantioselective copper/bisoxazoline catalyzed oxysulfonylation of alkenes to yield isoxazolinyl-containing β-chiral sulfones bearing quaternary carbon stereocenters with moderate to excellent yields and up to 96:4 er. The advantage and irreplaceability of this sulfur dioxide insertion catalytic system have been demonstrated by achieving transformations clearly unavailable with the previously reported sulfonyl chloride system. Additionally,the recoverability of the new-developed bisoxazoline ligand L9 and its reusability without any erosion of the catalytic activity and enantioselectivity further demonstrate the usefulness of the protocol.

关键词： β-chiral sulfones sulfur dioxide insertion oxysulfonylation copper catalysis enantioselectivity

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Characteristics,origins,and significance of pyrites in deep-water shales

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Science China Earth Sciences 2024年第2期67卷 313-342页

作者： Chao LIANG shichao JI Yingchang CAO Keyu LIU Jing wu fang HAO National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China School of Geosciences China University of PetroleumQingdao266000China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China

As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their *** on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this *** the microscopic scale,each type of pyrite is associated with a different formation *** are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous *** pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal *** morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron *** addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen ***,pyrite can also serves as an indicator of shale gas reservoirs.

关键词： Shale Pyrite Sulfate reduction reaction Isotope fractionation Pyrite element

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Assessment of pathogenicity and functional characterization of APPL1 gene mutations in diabetic patients

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World Journal of Diabetes 2024年第2期15卷 275-286页

作者： Ping shi Yang Tian Feng Xu Lu-Na Liu Wan-Hong wu Ying-Zhou shi An-Qi Dai Hang-Yu fang Kun-Xia Li Chao Xu Department of Endocrinology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina Department of Pediatric Yantai Yuhuangding Hospital Affiliated to Qingdao UniversityYantai 264099Shandong ProvinceChina

BACKGROUND Adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 1(APPL1)plays a crucial role in regulating insulin signaling and glucose *** in the APPL1 gene have been associated with the development of maturity-onset diabetes of the young type 14(MODY14).Currently,only two mutations[c.1655T>A(***552*)and c.281G>A p.(Asp94Asn)]have been identified in association with this *** the limited understanding of MODY14,it is imperative to identify additional cases and carry out comprehensive research on MODY14 and APPL1 *** To assess the pathogenicity of APPL1 gene mutations in diabetic patients and to characterize the functional role of the APPL1 *** Patients exhibiting clinical signs and a medical history suggestive of MODY were screened for the *** exome sequencing was performed on the patients as well as their family *** pathogenicity of the identified APPL1 variants was predicted on the basis of bioinformatics *** addition,the pathogenicity of the novel APPL1 variant was preliminarily evaluated through in vitro functional ***,the impact of these variants on APPL1 protein expression and the insulin pathway were assessed,and the potential mechanism underlying the interaction between the APPL1 protein and the insulin receptor was further *** A total of five novel mutations were identified,including four missense mutations(Asp632Tyr,Arg633His,Arg532Gln,and Ile642Met)and one intronic mutation(1153-16A>T).Pathogenicity prediction analysis revealed that the Arg532Gln was pathogenic across all *** Asp632Tyr and Arg633His variants also had pathogenicity based on *** addition,multiple alignment of amino acid sequences showed that the Arg532Gln,Asp632Tyr,and Arg633His variants were conserved across different ***,in in vitro functional experiments,both the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations

关键词： Adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 1 Maturity-onset diabetes of the young Bioinformatics analysis Gene mutation Domain

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Evaluation of Well Spacing for Primary Development of Fractured Horizontal Wells in Tight Sandstone Gas Reservoirs

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1015-1030页

作者： fang Li Juan wu Haiyong Yi Lihong wu Lingyun Du Yuan Zeng Exploration and Development Research Institute PetroChina Southwest Oil&Gas Field CompanyChengdu610041China Oil and Gas Resources Department PetroChina Southwest Oil&Gas Field CompanyChengdu610000China

Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage *** this study,the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage *** the basis of these experiments,a numerical simulation model(based on the special seepage mechanism)and an inverse dynamic reserve algorithm(with different equivalent drainage areas)were *** well spacing ranges of Classes I,II,and III wells in the Q gas field are determined to be 802–1,000,600–662,and 285–400 m,respectively,with their average ranges as 901,631,and 342.5 m,*** considering both the pairs of parallel well groups and series well groups as examples,the reliability of the calculation results is *** is shown that the combination of the two models can reduce errors and provide accurate results.

关键词： Well spacing for primary development tight gas reservoir fractured horizontal well threshold pressure gradient stress sensitivity

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Local field potentials,spiking activity,and receptive fields in human visual cortex

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Science China(Life Sciences) 2024年第3期67卷 543-554页

作者： Lu Luo Xiongfei Wang Junshi Lu Guanpeng Chen Guoming Luan wu Li Qian Wang fang fang School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health Peking UniversityBeijing 100871China School of Psychology Beijing Sport UniversityBeijing 100084China Department of Neurosurgery Sanbo Brain HospitalCapital Medical UniversityBeijing 100093China Beijing Key Laboratory of Epilepsy Epilepsy CenterSanbo Brain HospitalCapital Medical UniversityBeijing 100093China IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeijing 100871China Beijing Institute for Brain Disorders Beijing 100069China State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China

The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2/V3). We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–30 Hz) were larger than those estimated from low-gamma activity(LGA, 30–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.

关键词： human visual cortex receptive field intracranial EEG local field potential spiking activity

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An all-dielectric chiral metasurface with circular dichroism and asymmetric transmission characteristics

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Optoelectronics Letters 2024年第9期20卷 537-542页

作者： wu Qihang shi Zhuolin HE Jinglin DONG Jianfeng Department of Electronic Information Science and Technology Ningbo UniversityNingbo 31521lChina

This paper designs an all-dielectric metasurface with tunable chiral properties in the near-infrared range,whose working wavelength is 1250-2200 *** metasurface exhibits circular dichroism(CD)and asymmetric transmission(AT)characteristics for circularly polarized *** metasurface is a double-layer structure composed of Ge_(2)Sb_(2)Se_(4)Te_(1)(GSST).

关键词： circular dielectric chiral

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A reinforcement learning approach to vehicle coordination for structured advanced air mobility

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Green Energy and Intelligent Transportation 2024年第2期3卷 20-37页

作者： Sabrullah Deniz Yufei wu Yang shi Zhenbo Wang Department of Mechanical Aerospaceand Biomedical EngineeringThe University of TennesseeKnoxvilleTN37996USA

Advanced Air Mobility(AAM)has emerged as a pioneering concept designed to optimize the efficacy and ecological sustainability of air *** core objective is to provide highly automated air transportation services for passengers or cargo,operating at low altitudes within urban,suburban,and rural *** seeks to enhance the efficiency and environmental viability of the aviation sector by revolutionizing the way air travel is *** a complex aviation environment,traffic management and control are essential technologies for safe and effective AAM *** of the most difficult obstacles in the envisioned AAM systems is vehicle coordination at merging points and *** escalating demand for air mobility services,particularly within urban areas,poses significant complexities to the execution of such *** this study,we propose a novel multi-agent reinforcement learning(MARL)approach to efficiently manage high-density AAM operations in structured *** approach provides effective guidance to AAM vehicles,ensuring conflict avoidance,mitigating traffic congestion,reducing travel time,and maintaining safe ***,intelligent learning-based algorithms are developed to provide speed guidance for each AAM vehicle,ensuring secure merging into air corridors and safe passage through *** validate the effectiveness of our proposed model,we conduct training and evaluation using BlueSky,an open-source air traffic control simulation *** the simulation of thousands of aircraft and the integration of real-world data,our study demonstrates the promising potential of MARL in enabling safe and efficient AAM *** simulation results validate the efficacy of our approach and its ability to achieve the desired outcomes.

关键词： Advanced Air Mobility(AAM) Urban Air Mobility(UAM) Air Traffic Control(ATC) Multi-Agent Reinforcement Learning(MARL)

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