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A Cloud-Fog Enabled and Privacy-Preserving IoT Data Market Platform Based on Blockchain

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2237-2260页

作者： Yurong Luo wei you Chao Shang Xiongpeng Ren Jin Cao Hui Li School of Cyber Engineering State Key Laboratory of Integrated Service NetworkXidian UniversityXi’an710126China

The dynamic landscape of the Internet of Things(IoT)is set to revolutionize the pace of interaction among entities,ushering in a proliferation of applications characterized by heightened quality and diversity.Among the pivotal applications within the realm of IoT,as a significant example,the Smart Grid(SG)evolves into intricate networks of energy deployment marked by data integration.This evolution concurrently entails data interchange with other IoT entities.However,there are also several challenges including data-sharing overheads and the intricate establishment of trusted centers in the IoT ecosystem.In this paper,we introduce a hierarchical secure data-sharing platform empowered by cloud-fog integration.Furthermore,we propose a novel non-interactive zero-knowledge proof-based group authentication and key agreement protocol that supports one-to-many sharing sets of IoT data,especially SG data.The security formal verification tool shows that the proposed scheme can achieve mutual authentication and secure data sharing while protecting the privacy of data providers.Compared with previous IoT data sharing schemes,the proposed scheme has advantages in both computational and transmission efficiency,and has more superiority with the increasing volume of shared data or increasing number of participants.

关键词： IoT data sharing zero-knowledge proof authentication privacy preserving blockchain

Clinical Value of the Quantitative Flow Ratio to Predict Long-term Target Vessel Failure in Patients with In-stent Restenosis after Drug-coated Balloon Angioplasty

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Current Medical Science 2024年第3期44卷 561-567页

作者： Xiang-qi WU Long-bo LI wei you Zhi-ming WU Lei ZHAO Zhi-hui WANG Pei-na MENG Bin LIU Fei YE Department of Cardiology Nanjing First HospitalNanjing Medical UniversityNanjing210006China Department of Cardiology The Second Hospital of Jilin UniversityJilin130000China

Objective The study sought to investigate the clinical predictive value of quantitative flow ratio(QFR)for the long-term target vessel failure(TVF)outcome in patients with in-stent restenosis(ISR)by using drug-coated balloon(DCB)treatment after a long-term follow-up.Methods This was a retrospective study.A total of 186 patients who underwent DCB angioplasty for ISR in two hospitals from March 2014 to September 2019 were enrolled.The QFR of the entire target vessel was measured offline.The primary endpoint was TVF,including target vessel-cardiac death(TV-CD),target vessel-myocardial infarction(TV-MI),and clinically driven-target vessel revascularization(CD-TVR).Results The follow-up time was 3.09±1.53 years,and 50 patients had TVF.The QFR immediately after percutaneous coronary intervention(PCI)was significantly lower in the TVF group than in the no-TVF group.Multivariable Cox regression analysis indicated that the QFR immediately after PCI was an excellent predictor for TVF after the long-term follow-up[hazard ratio(HR):5.15×10−5(6.13×10−8−0.043);P<0.01].Receiver-operating characteristic(ROC)curve analysis demonstrated that the optimal cut-off value of the QFR immediately after PCI for predicting the long-term TVF was 0.925(area under the curve:0.886,95%confidence interval:0.834–0.938;sensitivity:83.40%,specificity:88.00;P<0.01).In addition,QFR≤0.925 post-PCI was strongly correlated with the TVF,including TV-MI and CD-TVR(P<0.01).Conclusion The QFR immediately after PCI showed a high predictive value of TVF after a long-term follow-up in ISR patients who underwent DCB angioplasty.A lower QFR immediately after PCI was associated with a worse TVF outcome.

关键词： percutaneous coronary intervention in-stent restenosis target vessel failure quantitative flow ratio

Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China

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Acta Geochimica 2024年第3期43卷 441-458页

作者： Qing-Qing Zhang you-wei Chen Jian-Feng Gao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South China.The Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained granite.The deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and sericitization.This study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and veins.Trace element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge compensators.Low Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic origin.The low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization temperatures.In contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten miner-alization.Ti contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°C.Variations in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH variations.Consequently,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit.

关键词： Quartz Xingluokeng Tungsten deposit Trace elements South China

Effect of negative remodeling of the side branch ostium on the efficacy of a two-stent strategy for distal left main bifurcation lesions:an intravascular ultrasound study

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Journal of Geriatric Cardiology 2024年第5期21卷 506-522页

作者： Yi XU Tian XU Jia-Cong NONG Xiao-Han KONG Meng-Yao ZHAO Zhi-Jing GAO Yi-Fei WANG wei you Pei-Na MENG Yu-He ZHOU Xiang-Qi WU Zhi-Ming WU Mei-En ZHAN Yan-Qing WANG De-Feng PAN Fei YE Department of Cardiology Nanjing First HospitalNanjing Hospital Affiliated to Nanjing Medical UniversityNanjing Medical UniversityNanjingChina Department of Cardiology Clinical Medicine School of Nanjing UniversityNanjingChina Department of Cardiology Tianchang People’s HospitalTianchangChina Department of Cardiology the Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina

OBJECTIVES To investigate whether negative remodeling(NR)detected by intravascular ultrasound(IVUS)of the side branch ostium(SBO)would affect in-stent neointimal hyperplasia(NIH)at the one-year follow-up and the clinical outcome of target lesion failure(TLF)at the long-term follow-up for patients with left main bifurcation(LMb)lesions treated with a two-stent strategy.METHODS A total of 328 patients with de novo true complex LMb lesions who underwent a 2-stent strategy of percutaneous coronary intervention(PCI)treatment guided by IVUS were enrolled in this study.We divided the study into two phases.Of all the patients,48 patients who had complete IVUS detection pre-and post-PCI and at the 1-year follow-up were enrolled in phase I analysis,which aimed to analyze the correlation between NR and in-stent NIH at SBO at the 1-year follow-up.If the correlation was confirmed,the cutoff value of the remodeling index(RI)for predicting NIH≥50%was analyzed next.The phase II analysis focused on the incidence of TLF as the primary endpoint at the 1-to 5-year follow-up for all 328 patients by grouping based on the cutoff value of RI.RESULTS In phase I:according to the results of a binary logistic regression analysis and receiver operating characteristic(ROC)analysis,the RI cutoff value predicting percent NIH≥50%was 0.85 based on the ROC curve analysis,with a sensitivity of 85.7%,a specificity of 88.3%,and an AUC of 0.893(0.778,1.000),P=0.002.In phase II:the TLR rate(35.8%vs.5.3%,P<0.0001)was significantly higher in the several NR(sNR,defined as RI≤0.85)group than in the non-sNR group.CONCLUSION The NR of LCxO is associated with more in-stent NIH post-PCI for distal LMb lesions with a 2-stent strategy,and NR with RI≤0.85 is linked to percent NIH area≥50%at the 1-year follow-up and more TLF at the 5-year follow-up.

关键词： lesions remodeling intravascular

Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin

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Petroleum Science 2024年第1期21卷 87-99页

作者： Yan-Nan Du Kong-you Wu Yin Liu Yan-Ying Li Zi-Cheng Cao you-wei Cui Jun Liu Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina Exploration and Development Research Institute SINOPEC Northwest Oilfield BranchUrumqi 830011XinjiangChina The Fifth Gas Production Plant Changqing OilfieldPetroChinaXi'an 710018ShaanxiChina

With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention recently.Affected by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related structures.In contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon accumulation.In this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim Basin.High-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic characteristics.Then,the stress state of each point of the STGs was calculated using seismic curvature attributes.Finally,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were discussed.The results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped bending.These STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both ends.The shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient reservoirs.This study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area.

关键词： Tarim Basin Sigmoidal tension gashes Seismic attributes Shear stress calculation Formation mechanism Reservoir control

Integrating Au and ZnO nanoparticles onto graphene nanosheet for enhanced sonodynamic therapy

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Nano Research 2022年第10期15卷 9223-9233页

作者： Fei Wang Boyu Wang wei you Guang Chen Ye-Zi you Neurosurgical Department the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China

Sonodynamic therapy has attracted widespread attention for cancer treatment because of its noninvasiveness and high tissuepenetration ability.Generally,ultrasound irradiation of sonosensitizers produces separated electrons(e−)and holes(h+),which inhibits cancer by producing reactive oxygen species(ROS).However,the separated electrons(e−)and holes(h+)could easily recombine,lowering the yield of ROS and hindering the application of sonodynamic therapy(SDT).Herein,we present a highly efficient sonosensitizer system for enhanced sonodynamic therapy built on reduced graphene oxide(rGO)nanosheets,bridged ZnO and Au nanoparticles,coated with polyvinyl pyrrolidone(PVP).The ultrasound irradiation activates ZnO nanoparticles to generate separated electron–hole(e−–h+)pairs,and the rGO nanosheets facilitate electron transfer from ZnO to Au nanoparticles because of the narrow band gap of rGO,which could efficiently restrain the recombination of the e−–h+pairs,thereby significantly augmenting the production of ROS to kill cancer cells,such as U373MG,HeLa,and CT26 cells.Moreover,rGO nanosheets integrated with Au nanoparticles could catalyze the endogenous decomposition of H_(2)O_(2) into O_(2),which can alleviate hypoxic tumor microenvironment(TME).Therefore,the rational design of Au-rGO-ZnO@PVP nanomaterials can not only improve the efficiency of sonodynamic therapy,but also mitigate the hypoxic tumor microenvironment,which would provide a new perspective in the development of efficient sonosensitizers.

关键词： sonodynamic therapy reactive oxygen species reduced graphene oxide tumor

A combined denoising method of empirical mode decomposition and singular spectrum analysis applied to Jason altimeter waveforms: A case of the Caspian Sea

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Geodesy and Geodynamics 2022年第4期13卷 327-342页

作者： Wenguan Jiang wei you Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Third Geodetic Team of the Department of Natural Resources Chengdu 610100China State-Province Joint Engineering Laboratory of Spatial Information Technology for High-Speed Railway Safety Chengdu 610031China

During the satellite pulse propagation and reception, the altimeter waveform is inevitably affected by noise. To reduce the noise level in Jason altimeter waveforms, we used singular spectrum analysis(SSA),empirical mode decomposition(EMD), and the combination of SSA and EMD to obtain the denoised waveforms. The advantages of the combined method were verified and the accuracy of the mean sea surface height(MSSH) model was improved. Comparing the denoising effect of the three methods, the results show that the signal-to-noise ratio(SNR), correlation coefficient and root-mean-square error are effectively improved by the combination of SSA and EMD. The sea surface heights(SSHs) were remeasured with a 50% threshold retracker of denoised waveforms, and the MSSH model of the Caspian Sea with a grid of 1’× 1’was established from the retracked SSHs of Jason-1/2/3. Taking the mean value of the four models as a control, it is found that the model calculated by the combined denoising method has the highest accuracy. This indicates that using the combined denoising method to reduce the noise level is beneficial to improve the accuracy of the MSSH model.

关键词： Altimetry waveforms Jason-1/2/3 Combined method Waveform retracking Mean sea surface height

Ring-opening metathesis polymerization of cyclopropene derivatives towards polyolefin elastomer analogues

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Science China Chemistry 2022年第11期65卷 2182-2187页

作者： Jing Bai Yu Wang wei you Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing 100049China

Polyolefin elastomers(POEs) are important reprocessable industrial materials with high strain-recovery performance. Traditional POEs are prepared from transition-metal-catalyzed polymerization of ethylene and α-olefins, while because of the complicated coordination polymerization mechanism, defining the actual distribution and length of alkyl branches in POEs is extremely challenging. We herein propose an alternative approach of synthesizing POE analogues from ring-opening metathesis polymerization(ROMP) of highly strained 3,3-alkyl-substituted cyclopropenes(CPEs). The structures of monomers and the substituents of Ru-catalysts are investigated in detail to evaluate the homobenzyl-substituted CPE derivative as a new living ROMP monomer. After copolymerization with cyclooctene and backbone hydrogenation, POE analogues with well-defined alkyl branches are prepared. Since the ROMP reactions have little isomerization and can also give good control of molecular weight and copolymer composition, it is hypothesized that this synthetic approach provides a novel platform to assist understanding the influence of branches on the properties of POEs.

关键词： cyclopropenes ring-opening metathesis polymerization polyolefin elastomers alkyl substituents

Experimental and numerical investigation on the mechanical responses and cracking mechanism of 3D confined single-flawed rocks under dynamic loading

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第2期14卷 477-493页

作者： wei you Feng Dai Yi Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

Accurately characterizing the mechanical responses and cracking mechanism of three-dimensional confined fractured rocks under coupled static-dynamic loading is of paramount importance for underground engineering construction.Using a modified split Hopkinson pressure bar(SHPB)system,five groups of single-flawed specimens with the axial prestress ratio from 0 to 0.8 are tested at the strain rates in the range of 65-205 s-1under a fixed radial prestress.Our results indicate that both the dynamic strength and total strength show significant positive linear correlations with the strain rate,and the dynamic strength shows more strain rate sensitivity under higher axial prestress.The dynamic strength and corresponding failure strain decrease with increasing axial prestress,while the total strength is barely affected by the axial prestress.The dynamic elastic modulus initially increases before the axial prestress ratio reaches 0.6 and then decreases.The failure pattern of tested specimens changes from single diagonal failure to an“X”shaped conjugated failure as axial prestress increases.Furthermore,the progressive cracking processes of confined single-flawed specimens under different axial prestresses are numerically visualized by the discrete element method(DEM).Based on the displacement trend lines on both sides of cracking surface,five crack types are identified and classified in our simulation.The displacement field distributions of the DEM models reveal that the macroscopic single diagonal failure under lower axial prestress is mainly controlled by mixed tensile-shear cracks,while the“X”shaped conjugated failure under higher axial prestress is shear dominated.

关键词： Confined flawed rock Split hopkinson pressure bar(SHPB) Cracking mechanism Discrete element method(DEM)