检索结果-南通市图书馆

Chinese Chemical Letters 2003年第8期14卷 790-793页

作者： Xin Yong LIU Wen Fang XU jing de wu School of Pharmacy Shandong UniversityJinan 250012

A series of novel 3-alkylthio-4-arylideneamino-5-(2-furyl)-1, 2, 4-triazole derivatives were synthesized. Their chemical structures were confirmed with elemental analysis and spectral data. Endothelin(ET) receptor c... 详细信息

关键词： Triazole derivatives ET antagonist.

维普期刊数据库

A buffer overflow detection and defense method based on RiSC-V instruction set extension

在线全文

学校读者我要写书评

暂无评论

Cybersecurity 2024年第2期7卷 28-43页

作者： Chang Liu Yan-Jun wu jing-Zheng wu Chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating *** overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,deP,StackGuard,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security ***,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in *** to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

Benchmarking visual SLAM methods in mirror environments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computational Visual Media 2024年第2期10卷 215-241页

作者： Peter Herbert jing wu Ze Ji Yu-Kun Lai School of Computer Science and Informatics Cardiff UniversityAbacws BuildingSenghennydd RdCardiff CF244AGUK School of Engineering Cardiff UniversityQueen’s BuildingsThe ParadeCardiff CF243AAUK

Visual simultaneous localisation and mapping(vSLAM)finds applications for indoor and outdoor navigation that routinely subjects it to visual complexities,particularly mirror *** effect of mirror presence(time visible and its average size in the frame)was hypothesised to impact localisation and mapping performance,with systems using direct techniques expected to perform ***,a dataset,MirrEnv,of image sequences recorded in mirror environments,was collected,and used to evaluate the performance of existing representative *** ORB-SLAM3 and BundleFusion appear to show moderate degradation of absolute trajectory error with increasing mirror duration,whilst the remaining results did not show significantly degraded localisation *** mesh maps generated proved to be very inaccurate,with real and virtual reflections colliding in the reconstructions.A discussion is given of the likely sources of error and robustness in mirror environments,outlining future directions for validating and improving vSLAM performance in the presence of planar *** MirrEnv dataset is available at https://***/10.17035/d.2023.0292477898.

关键词： visual simultaneous localisation and mapping(vSLAM) mirror localisation mapping reflection datase

Effect of the yaw angle on turbulent flow structures around the submarine model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： Yi-jing Hu Yi Qu Qin wu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of Electronic System Engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

Major methods of seismic anisotropy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Research Advances 2024年第3期4卷 82-91页

作者： Xinai Zhao jing wu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China

Seismic anisotropy reveals that seismic wave velocity, amplitude, and other physical properties show variations in different directions, which can be divided into lattice-preferred orientation(LPO) and shape-preferred orientation(SPO) according to its physical mechanisms. The main methods for studying seismic anisotropy include shearwave splitting analysis, P-wave travel time inversion and surface-wave tomography, etc. There are some differences and correlations among these methods. Seismic anisotropy is an important way to reveal the dynamic processes of crust-mantle evolution, and it is significant for monitoring crustal stress changes and improve seismic exploration studies. With the help of long-term observation, the application of machine learning techniques and combining inversion based on multiple phases would become potential developments in seismic anisotropy studies. This may improve the understanding of complex seismic anisotropic models, such as multiple layers anisotropy with an oblique axis of symmetry.

关键词： Seismic anisotropy Shear-wave splitting P-wave travel time inversion Surface-wave tomography

维普期刊数据库

Non-alcoholic fatty liver degree and long-term risk of incident inflammatory bowel disease: A large-scale prospective cohort study

在线全文

学校读者我要写书评

暂无评论

中华医学杂志(英文版) 2024年第14期137卷 1705-1714页

作者： Zhang Qian Liu Si wu jing Zhu Shengtao wu Yongdong wu Shanshan Zhang Shutian department of Gastroenterology Beijing Friendship Hospital Capital Medical University National Clinical Research Center for Digestive Disease Beijing Digestive Disease Center Beijing Key Laboratory for Precancerous Lesion of Digestive Disease Beijing China

Background: Non-alcoholic fatty liver disease (NAFLD) and inflammatory bowel disease (IBD) have shown similar worsening epidemic patterns globally and shared various overlapping pathophysiological mechanisms. However, evidence on the relationship between NAFLD and IBD risk is lacking. We aimed to investigate the associations between long-term risk of incident IBD and NAFLD in a large prospective ***: Participants from the United Kingdom Biobank cohort (https://***/) who were free of IBD and alcoholic liver disease at baseline were enrolled. Baseline non-alcoholic fatty liver degree was measured by the well-established fatty liver index (FLI). The outcomes of interest included incident IBD, ulcerative colitis (UC), and Crohn’s disease (CD). Multivariable Cox proportional hazard regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).Results: Among 418,721 participants (mean FLI: 48.11 ± 30.11), 160,807 (38.40%) participants were diagnosed as NAFLD at baseline. During a median of 12.4 years’ follow-up, 2346 incident IBD cases (1545 UC, 653 CD, and 148 IBD-unclassified) were identified. Due to limited events, those IBD-unclassified were combined in UC or CD when examining the associated risk of UC or CD, separately. Compared with the lowest quartile of FLI, the highest quartile showed a separately 36.00%, 25.00%, and 58.00% higher risk of incident IBD (HRQ4vs. Q1 =1.36, 95% CI: 1.19-1.55,Ptrend dent IBD (HR=1.13, 95% CI: 1.04-1.24) and CD (HR =1.36, 95% CI: 1.17-1.58).Conclusions: Higher degree of non-alcoholic fatty liver is associated with increased risk of incident IBD. Interventions aimed at improving NAFLD may be a potential targeted strategy for the detection and treatm

关键词： Non-alcoholic fatty liver disease Inflammatory bowel disease Ulcerative colitis Crohn’s disease Cohort study

Targeting synaptic pathology in Alzheimer’s disease

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2024年第4期45卷 875-876页

作者： jing Cao Yun-wu Zhang Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceSchool of MedicineXiamen UniversityXiamenFujian 361102China

Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by memory and cognitive *** two primary pathological hallmarks of AD include the accumulation ofβ-amyloid(Aβ)plaques and formation of neurofibrillary tangles(NFTs)composed predominantly of hyperphosphorylated tau protein(Zhang et al.,2023).Moreover,synaptic dysfunction is considered another crucial factor in AD pathogenesis and is closely associated with cognitive ***,synaptic damage,loss,and dysfunction manifest earlier than the pathological features of Aβplaques and NFTs(Knopman et al.,2021).Therefore,understanding the mechanisms underlying synaptic dysfunction in AD is vital for providing insights into disease mechanisms and developing novel therapeutic strategies.

关键词： Alzheimer Aβ tau

维普期刊数据库

Adaptive Graph Convolutional Adjacency Matrix Network for Video Summarization

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第8期80卷 1947-1965页

作者： jing Zhang Guangli wu Shanshan Song School of Cyberspace Security Gansu University of Political Science and LawLanzhou730000China

Video summarization aims to select key frames or key shots to create summaries for fast retrieval,compression,and efficient browsing of *** neural networks efficiently capture information about graph nodes and their neighbors,but ignore the dynamic dependencies between *** address this challenge,we propose an innovative Adaptive Graph Convolutional Adjacency Matrix Network(TAMGCN),leveraging the attention mechanism to dynamically adjust dependencies between graph ***,we first segment shots and extract features of each frame,then compute the representative features of each ***,we utilize the attention mechanism to dynamically adjust the adjacency matrix of the graph convolutional network to better capture the dynamic dependencies between graph ***,we fuse temporal features extracted by Bi-directional Long Short-Term Memory network with structural features extracted by the graph convolutional network to generate high-quality *** experiments are conducted on two benchmark datasets,TVSum and SumMe,yielding F1-scores of 60.8%and 53.2%,*** results demonstrate that our method outperforms most state-of-the-art video summarization techniques.

关键词： Attention mechanism deep learning graph neural network key-shot video summarization

defects in phospholipase C zeta cause polyspermy and low fertilization after conventional IVF:not just ICSI failure

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2024年第2期26卷 175-182页

作者： Jian-Fang Che Hui-Xia wu Si-Cong Zeng Yue-Ren wu jing Dai de-Hua Cheng Fei Gong Guang-Xiu Lu Ge Lin Can Dai School of Medicine Hunan Normal UniversityChangsha 410013China Reproductive and Genetic Hospital of CITIC-Xiangya Changsha 410008China Clinical Research Center for Reproduction and Genetics in Hunan Province Changsha 410078China National Engineering and Research Center of Human Stem Cell Changsha 410205China

Phospholipase C zeta(PLC)is a key sperm-borne oocyte-activating factor that triggers Ca^(2+)oscillations and the subsequent block to polyspermy following gamete *** in PLCZ1,the gene encoding PLCζ,cause male infertility and intracytoplasmic sperm injection(ICSI)fertilization failure;and PLCζ expression and localization patterns are significantly correlated with ICSI fertilization rate(FR).However,in conventional in vitro fertilization(cIVF),whether and how sperm PLCζ affects fertilization remain ***,we identified one previously reported and two novel PLCZ1 mutations associated with polyspermy in vitro that are characterized by excessive sperm-zona binding and a delay in pronuclei(PN)*** staining and oocyte activation testing revealed that virtually all spermatozoa from patients lacked functional PLCζ and were thus unable to evoke Ca^(2+) *** with an artificial oocyte activation treatment successfully rescued the polyspermic phenotype and resulted in a live ***,we analyzed PLCζ in an additional 58 males after cIVF treatment in the Reproductive and Genetic Hospital of CiTiC-Xiangya(Changsha,China)between February 2019 and January *** found that the proportion of spermatozoa that expressed PLCζ was positively correlated with both 2PN rate and total *** optimal cutoff value below which males were likely to experience low FR(total FR≤30%)after clVF was 56.7%for the proportion of spermatozoa expressing *** study expands the mutation and the phenotypic spectrum of PLCZ1 and further suggests that PLCζ constitutes a promising biomarker for identifying low FRs cases in cIVF due to sperm-related oocyte activation deficiency and that sperm PLCζ analysis may benefit the widermale population and not onlymen with IcsI failure.

关键词： conventional IVF gene variants PLCζ polyspermy

Highly active and durable core-shell electrocatalysts for proton exchange membrane fuel cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第10期17卷 8772-8784页

作者： Hsiwen wu Fei Xiao jing Wang Meng Gu Minhua Shao department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Fok Ying Tung Research Institute The Hong Kong University of Science and TechnologyGuangzhou 511458China Energy Institute and Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution The Hong Kong University of Science and TechnologyClear Water BayHong KongChina

This work presents simple post-treatment methods to selectively and partially remove the Pd core of Pd-Pt core–shell(Pt@Pd/C)*** proton exchange membrane fuel cell with the post-treated Pt@Pd/C cathode(Pt loading:0.10 mg·cm^(-2))delivers an impressive peak power density of 1.2 W·cm^(-2).The partial removal of Pd core endows an ultrahigh oxygen reduction reaction(ORR)mass activity of 0.32 A·g_(PGM)-1 when normalized to the platinum group metal(PGM)mass,or equivalently 0.55 A·mg_(Pt)^(-1) at 0.9 V measured in a fuel *** post-treatment thickens the Pt shells and mitigates the Pd dissolution during potential *** a result,the post-treated core-shell catalyst demonstrates superior durability in ORR mass activity and polarization power density retention than untreated core-shell catalyst and benchmark Pt/***-situ inductively coupled plasmamass spectrometry(ICP-MS)results highlight that the amount of dissolved Pd in post-treated core–shell catalyst is 17-times lower than that of the untreated *** findings highlight the importance of structural tuning of catalysts in enhancing their mass activity and durability.

关键词： core-shell catalyst platinum monolayer proton exchange membrane fuel cell oxygen reduction reaction durability