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Application of dezocine patient-controlled epidural analgesia in postoperative analgesia in patients with total myomectomy

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World Journal of Clinical Cases 2024年第20期12卷 4265-4271页

作者： feng-feng ning Ting-Ting Yao Xiao-Xia Wang Department of Anesthesiology Gansu Provincial Maternity and Child-care HospitalLanzhou 730050Gansu ProvinceChina Department of Gynecology Gansu Provincial Maternity and Child-Care HospitalLanzhou 730050Gansu ProvinceChina

BACKGROUND Uterine fibroids are common benign gynecological *** who experience excessive menstruation,anemia,and pressure symptoms should be administered medication,and severe cases require a total *** procedure is invasive and causes severe postoperative pain,which can affect the patient’s postoperative sleep quality and,thus,the recovery *** To evaluate use of dezocine in patient-controlled epidural analgesia(PCEA)for postoperative pain management in patients undergoing total *** We selected 100 patients undergoing total abdominal hysterectomy for uterine fibroids and randomized them into two groups:A control group receiving 0.2%ropivacaine plus 0.06 mg/mL of morphine and an observation group receiving 0.2%ropivacaine plus 0.3 mg/mL of diazoxide in their *** assessed included pain levels,sedation,recovery indices,PCEA usage,stress factors,and sleep *** The observation group showed lower visual analog scale scores,shorter postoperative recovery indices,fewer mean PCEA compressions,lower cortisol and blood glucose levels,and better polysomnographic parameters compared to the control group(P<0.05).The cumulative incidence of adverse reactions was lower in the observation group than in the control group(P<0.05).CONCLUSION Dezocine PCEA can effectively control the pain associated with total myomectomy,reduce the negative impact of stress factors,and have less impact on patients’sleep,consequently resulting in fewer adverse effects.

关键词： Diazoxide Patient-controlled epidural analgesia Total hysterectomy Sleep impacts Adverse effects

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CToMP: a cycle-task-oriented memory protection scheme for unmanned systems

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Science China(Information Sciences) 2024年第6期67卷 399-417页

作者： Chengyan MA ning XI Di LU Yebo feng Jianfeng MA School of Cyber Engineering Xidian University School of Computer Science and Technology Xidian University Department of Computer and Information Science University of Oregon

Memory corruption attacks(MCAs) refer to malicious behaviors of system intruders that modify the contents of a memory location to disrupt the normal operation of computing systems, causing leakage of sensitive data or perturbations to ongoing processes. Unlike general-purpose systems, unmanned systems cannot deploy complete security protection schemes, due to their limitations in size, cost and *** in unmanned systems are particularly difficult to defend against. Furthermore, MCAs have diverse and unpredictable attack interfaces in unmanned systems, severely impacting digital and physical sectors. In this paper, we first generalize, model and taxonomize MCAs found in unmanned systems currently, laying the foundation for designing a portable and general defense approach. According to different attack mechanisms,we found that MCAs are mainly categorized into two types — return2libc and return2shellcode. To tackle return2libc attacks, we model the erratic operation of unmanned systems with cycles and then propose a cycle-task-oriented memory protection(CToMP) approach to protect control flows from tampering. To defend against return2shellcode attacks, we introduce a secure process stack with a randomized memory address by leveraging the memory pool to prevent Shellcode from being executed. Moreover, we discuss the mechanism by which CTo MP resists the return-oriented programming(ROP) attack, a novel variant of return2libc attacks. Finally, we implement CTo MP on CUAV V5+ with Ardupilot and Crazyflie. The evaluation and security analysis results demonstrate that the proposed approach CTo MP is resilient to various MCAs in unmanned systems with low footprints and system overhead.

关键词： unmanned system memory corruption attack memory protection system security randomized memory address

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Starlet:Network defense resource allocation with multi-armed bandits for cloud-edge crowd sensing in IoT

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Digital Communications and Networks 2024年第3期10卷 586-596页

作者： Hui Xia ning Huang Xuecai feng Rui Zhang Chao Liu College of Computer Science and Technology Ocean University of ChinaQingdao266100China

The cloud platform has limited defense resources to fully protect the edge servers used to process crowd sensing data in Internet of *** guarantee the network's overall security,we present a network defense resource allocation with multi-armed bandits to maximize the network's overall ***,we propose the method for dynamic setting of node defense resource thresholds to obtain the defender(attacker)benefit function of edge servers(nodes)and ***,we design a defense resource sharing mechanism for neighboring nodes to obtain the defense capability of ***,we use the decomposability and Lipschitz conti-nuity of the defender's total expected utility to reduce the difference between the utility's discrete and continuous arms and analyze the difference ***,experimental results show that the method maximizes the defender's total expected utility and reduces the difference between the discrete and continuous arms of the utility.

关键词： Internet of things Defense resource sharing Multi-armed bandits Defense resource allocation

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A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

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Petroleum Science 2024年第3期21卷 1865-1874页

作者： Ji Wang ning Qi Hong-Yao Yin Yu-Jun feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR.China Tianfu Yongxing Laboratory New Theory and Technology of CO_(2) Capture Research CenterChengdu610065SichuanPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well ***,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and *** reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs *** work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

关键词： Viscoelastic surfactants Thermal stability Self-diverting acid Wormlike micelles Acidizing stimulation

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Liquid-mediated Ostwald ripening of Ag-based clusters supported on oxides

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Nano Research 2024年第6期17卷 4971-4978页

作者： Conghui Liu Rongtan Li Yamei Fan Shiwen Li Xiaohui feng Lu feng Yanxiao ning Qiang Fu School of Chemistry Dalian University of TechnologyDalian 116024China State Key Laboratory of Catalysis Chinese Academy of SciencesDalian Institute of Chemical PhysicsDalian 116023China

Reconstruction of supported nanocatalysts often occurs in gas-solid reactions and significantly affects the catalytic performance,yet it is much less explored in liquid-phase ***,we find that highly-dispersed Ag nanocatalysts,i.e.,AgOx clusters,supported on alumina,silica,and titania,can aggregate into larger Ag or Ag2O particles after immersing in liquid-phase media at room *** spontaneous aggregation of AgOx clusters in liquid water is attributed to liquid-phase Ostwald ripening through dissolution of AgOx clusters into water and subsequent redeposition to form Ag2O *** immersion into organic solvents such as ethanol leads to reduction of AgOx clusters and further growth into Ag *** work reveals that liquid-phase reaction media can induce substantial structural evolution of supported nanostructured catalysts,which should be carefully considered in liquid-solid interface catalytic reactions such as electrocatalysis,environmental catalysis,and organic synthesis in liquid phase.

关键词： Ag catalysts Ostwald ripening liquid phase media dissolution-deposition process

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Robot-Oriented 6G Satellite-UAV Networks: Requirements, Paradigm Shifts, and Case Studies

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China Communications 2024年第2期21卷 74-84页

作者： Peng Wei Wei feng Yunfei Chen ning Ge Wei Xiang Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Department of Engineering University of DurhamDH13LEDurhamUK School of Computing Engineering and Mathematical SciencesLa Trobe UniversityMelbourneVIC 3086Australia

Networked robots can perceive their surroundings, interact with each other or humans,and make decisions to accomplish specified tasks in remote/hazardous/complex environments. Satelliteunmanned aerial vehicle(UAV) networks can support such robots by providing on-demand communication services. However, under traditional open-loop communication paradigm, the network resources are usually divided into user-wise mostly-independent links,via ignoring the task-level dependency of robot collaboration. Thus, it is imperative to develop a new communication paradigm, taking into account the highlevel content and values behind, to facilitate multirobot operation. Inspired by Wiener’s Cybernetics theory, this article explores a closed-loop communication paradigm for the robot-oriented satellite-UAV network. This paradigm turns to handle group-wise structured links, so as to allocate resources in a taskoriented manner. It could also exploit the mobility of robots to liberate the network from full coverage,enabling new orchestration between network serving and positive mobility control of robots. Moreover,the integration of sensing, communications, computing and control would enlarge the benefit of this new paradigm. We present a case study for joint mobile edge computing(MEC) offloading and mobility control of robots, and finally outline potential challenges and open issues.

关键词： closed-loop communication mobility control satellite-UAV network structured resource allocation

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Exploration on electrical resistance tomography in characterizing the slurry spatial distribution in cemented granular materials

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 365-379页

作者： Bohao WANG Wei WANG feng JIN Handong TAN ning LIU Duruo HUANG State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China Institute of Science and Technology China Three Gorges CorporationBeijing 100038China School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China

This study investigated the application of electrical resistance tomography(ERT)in characterizing the slurry spatial distribution in cemented granular materials(CGMs).For CGM formed by self-flow grouting,the voids in the accumulation are only partially filled and the bond strength is often limited,which results in difficulty in obtaining in situ samples for quality ***,it is usually infeasible to evaluate the grouting effect or monitor the slurry spatial distribution by a mechanical *** this research,the process of grouting cement paste into high alumina ceramic beads(HACB)accumulation is reliably monitored with *** shows that ERT results can be used to calculate the cement paste volume in the HACB accumulation,based on calibrating the saturation exponent n in Archie’s *** results support the feasibility of ERT as an imaging tool in CGM characterization and may provide guidance for engineering applications in the future.

关键词： electrical resistance tomography cemented granular material grouting spatial distribution Archie’s law

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Significant enhancement in local thermal conductivity of erythritol at interface with nanoparticles due to their interaction

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Nano Research 2024年第8期17卷 7726-7736页

作者： ning Cao Yanhui feng Kening Yan Zihan Liu Jiawei Wan Lin Qiu School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

When nano-fillers are used to enhance the thermal conductivity of organic phase change materials(PCMs),the naturally formed interface is considered to hinder thermal transport of the composite ***,the effect of the interface on the thermal properties of surrounding PCM has not been fully *** this paper,three composite PCMs(Ery@SiC,Ery@SiO_(2) and Ery@Si_(3)N_(4))were prepared by melt-blending *** local thermal conductivity and reduced Young’s modulus(E^(*))of the erythritol at the interface and far away from the interface in the composite PCMs were simultaneously measured by scanning thermal microscopy(SThM).The results revealed significant enhancement in local thermal conductivity of erythritol at the interface and its obvious positive correlation with E^(*).For different composite PCMs,molecular dynamics(MD)simulations suggested that the increase in intrinsic thermal conductivity and E^(*)of erythritol is attributed to the increase in interaction energy between erythritol and nanoparticles,as more erythritol phonon vibrations transform from localized mode to delocalized mode and erythritol has a higher density at the *** findings will provide new ideas for the design of PCM for energy storage.

关键词： scanning thermal microscopy phase change materials thermal conductivity reduced Young’s modulus interaction energy phonon participation ratio

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Subnanometric bimetallic Pt-Pd clusters in zeolites for efficient hydrogen production and selective tandem hydrogenation of nitroarenes

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Science China Chemistry 2024年第9期67卷 2911-2917页

作者： Jiafu Li Tao Cai Yanran feng Xia Liu ning Wang Qiming Sun Institute of Sustainable Energy and Resources College of Chemistry and Chemical EngineeringKey Laboratory of Shandong Provincial Universities for Functional Molecules and MaterialsQingdao UniversityQingdao 266071China Innovation Center for Chemical Sciences College of ChemistryChemical Engineering and Materials ScienceJiangsu Key Laboratory of Advanced Negative Carbon TechnologiesSoochow UniversitySuzhou 215123China

The solvolysis of ammonia borane(AB)and the hydrogenation of nitroarenes represent significant reactions for hydrogen generation and value-added chemical *** strategic engineering of the catalysts is imperative for surmounting obstacles associated with their stability and catalytic *** this work,subnanometric bimetallic Pt–Pd clusters were encapsulated within silicalite-1(S-1)zeolites through a ligand-protected in-situ hydrothermal synthesis *** synergetic effect of bimetallic composition and zeolite confinement markedly enhances the catalytic performance of representative Pt_(0.5)Pd_(0.5)@S-1-H catalyst,affording exceptional turnover frequency(TOF)values of 1,043 and 573 mol_(H_(2))mol_(metal)^(-1)min^(-1)for AB hydrolysis and methanolysis at ambient conditions,respectively,surpassing most of the state-of-the-art Pt-based *** and isotopic experiments reveal that the bimetallic catalytic system remarkably boosts the O-H cleavage of water,thereby facilitating the H_(2) production from AB ***,a conspicuous synergistic effect is demonstrated in the shape-selective tandem hydrogenation of nitroarenes,with the bimetallic catalyst facilitating both AB hydrolysis and nitroarene hydrogenation,giving a high TOF value of 1,260 h^(-1)under atmospheric *** study not only demonstrates the effectiveness of bimetallic nanocatalysts encapsulated in zeolites for hydrogen production from chemical hydrogen storage materials,but also paves the way for the design of catalysts with multifunctional active sites capable of synergistically promoting tandem catalytic processes.

关键词： subnanometer bimetallic cluster zeolite synergistic effect ammonia borane solvolysis selective tandem hydrogenation

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Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy

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China Foundry 2024年第2期21卷 147-158页

作者： ning Wang Kai Ma Qiu-da Li Yu-dong Yuan Yan-chun Zhao Li feng School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals Lanzhou 730050China CNNC Nuclear Power Operation and Management Co. Ltd.Haiyan 314300ZhejiangChina

AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting *** microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal *** results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the ***(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these *** an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then ***,the area fraction initially decreases and then ***,the alloy’s strength and wear resistance decrease,while its plasticity *** Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·N^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively.

关键词： high-entropy alloys microstructure mechanical properties wear resistance strengthening mechanisms

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