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An Efficient Encrypted Speech Retrieval Based on Unsupervised Hashing and B+ Tree Dynamic Index
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作者 Qiu-yu Zhang Yu-gui Jia +1 位作者 Fang-Peng Li Le-Tian Fan 《Computers, Materials & Continua》 SCIE EI 2023年第7期107-128,共22页
Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech dat... Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech data to meet users’real-time retrieval requirements.This study proposes an efficient method for retrieving encryption speech,using unsupervised deep hashing and B+ tree dynamic index,which avoid privacy leak-age of speech data and enhance the accuracy and efficiency of retrieval.The cloud’s encryption speech library is constructed by using the multi-threaded Dijk-Gentry-Halevi-Vaikuntanathan(DGHV)Fully Homomorphic Encryption(FHE)technique,which encrypts the original speech.In addition,this research employs Residual Neural Network18-Gated Recurrent Unit(ResNet18-GRU),which is used to learn the compact binary hash codes,store binary hash codes in the designed B+tree index table,and create a mapping relation of one to one between the binary hash codes and the corresponding encrypted speech.External B+tree index technology is applied to achieve dynamic index updating of the B+tree index table,thereby satisfying users’needs for real-time retrieval.The experimental results on THCHS-30 and TIMIT showed that the retrieval accuracy of the proposed method is more than 95.84%compared to the existing unsupervised hashing methods.The retrieval efficiency is greatly improved.Compared to the method of using hash index tables,and the speech data’s security is effectively guaranteed. 展开更多
关键词 Encrypted speech retrieval unsupervised deep hashing learning to hash B+tree dynamic index DGHV fully homomorphic encryption
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Sensitivity analysis and dynamic modification of modal parameter in mechanical transmission system
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作者 XIE Shao-Wang CHEN Qi-Lian +1 位作者 CHEN Chang-Zheng LI Qing-Fen 《Journal of Marine Science and Application》 2005年第4期53-58,共6页
Sensitivity analysis is one of the effective methods in the dynamic modification. The sensitivity of the modal parameters such as the natural frequencies and mode shapes in undamped free vibration of mechanical transm... Sensitivity analysis is one of the effective methods in the dynamic modification. The sensitivity of the modal parameters such as the natural frequencies and mode shapes in undamped free vibration of mechanical transmission system is analyzed in this paper.In particular,the sensitivities of the modal parameters to physical parameters of shaft system such as the inertia and stiffness are given.A calculation formula for dynamic modification is presented based on the analysis of modal parameter.With a mechanical transmission system as an example, the sensitivities of natural frequencies and modes shape are calculated and analyzed. Furthermore, the dynamic modification is also carried out and a good result is obtained. 展开更多
关键词 transmission system modal parameter sensitivity analysis dynamic modification.
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Sex modification of the association of the radial augmentation index and incident hypertension in a Chinese community-based population
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作者 Qiao QIN Fang-Fang FAN +11 位作者 Meng-Yuan LIU Bo LIU Jia JIA Long ZHANG Yu-Xi LI Yi-Meng JIANG Peng-Fei SUN Dan-Mei HE Jian-Ping LI Ming CHEN Bo ZHENG Yan ZHANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2021年第1期39-46,共8页
BACKGROUND Arterial stiffness,as assessed by aortic ultrasound and pulse wave velocity,is associated with incident hypertension.However,there is still no consensus on whether the augmentation index(AI)affects new onse... BACKGROUND Arterial stiffness,as assessed by aortic ultrasound and pulse wave velocity,is associated with incident hypertension.However,there is still no consensus on whether the augmentation index(AI)affects new onset of hypertension.This study investigated the relationship of radial AI(r AI)and incident hypertension in a Chinese community-based population without hypertension at baseline.METHOD A total of 1,615 Chinese non-hypertensive participants from an atherosclerosis cohort in Beijing,China were included in our analysis.Baseline r AI normalized to heart rate of 75 beats/min(r AIp75)was obtained using HEM-9000 AI.New-onset hypertension was defined as blood pressure≥140/90 mm Hg or self-reported hypertension or taking anti-hypertensive medications at the follow up survey.Multivariate regression models were used to evaluate the impact of r AIp75 on the risk of new-onset hypertension.RESULTS After a mean 2.35-year follow-up,213(13.19%)participants developed incident hypertension.No significant relation between r AIp75 and incident hypertension was observed in the whole population after adjustment for possible confounders(adjusted odds ratio(OR)and 95%confidence interval(CI):1.09[0.95-1.27];P=0.2260).However,r AIp75 was significantly associated with incident hypertension in women,but not in men(adjusted OR and 95%CI:1.29[1.06-1.56],P=0.0113 for women;0.91[0.72-1.15],P=0.4244 for men;P for interaction=0.0133).CONCLUSIONS Sex modified the effect of the r AI on incident hypertension in a Chinese,community-based,non-hypertensive population.Screening of the r AI could be considered in women with a high risk of hypertension for the purpose of primary intervention. 展开更多
关键词 Sex modification of the association of the radial augmentation index and incident hypertension in a Chinese community-based population
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Effect of Tooth Profile Modification on Vibration of Power Split Gear Transmission System 被引量:2
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作者 Jincheng Dong Sanmin Wang +1 位作者 Jiashun Guo He Lin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第3期61-68,共8页
Based on Newton ' s second law,the bend-torsion-shaft coupling nonlinear dynamic model and equations of power split gear transmission system are established.According to the principle of tooth profile modification... Based on Newton ' s second law,the bend-torsion-shaft coupling nonlinear dynamic model and equations of power split gear transmission system are established.According to the principle of tooth profile modification,the tooth profile modification is considered as time-varying gear backlash function acting along the line of action.Then the dynamic functions are solved by using Runge-Kutta numerical method.After analyzing the effect of tooth profile modification quantity( TPMQ) and relative tooth profile modification length( TPML) to the nonlinear dynamic characteristics of power split gear transmission,the following conclusions are drawn:1 The TPMQ of a certain stage transmission affects the vibration of its own stage more significantly than the other stage,and the coupling effect between two stages can be ignored usually in the modification design;2 If the first stage TPMLs are less than 0.3,the influence of the first stage TPMLs to the first stage transmission vibration is much more greatly than the influence of the second stage TPMLs to the first stage transmission vibration,or else both the first and second stage TPMLs affect the first stage transmission vibration largely.The same is true for the second stage TPMLs,and the cutoff value is 0.2;3 The TPMQ affects the vibration of power split gear transmission system more principally than the TPML,and should be top-priority in the modification design. 展开更多
关键词 power SPLIT GEAR transmission system TOOTH profile modification nonlinear dynamic characteristics TIME-VARYING GEAR BACKLASH function
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TRIGONOMETRIC CURVE MODIFICATION OF SCROLL PROFILE AND ITS EFFECT ON PERFORMANCES OF A SCROLL COMPRESSOR 被引量:5
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作者 Liu Tao Liu Zhenquan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期498-503,共6页
A modification of central profile with trigonometric curve is proposed based on the theory of engagement of scroll compressor. General modification equations for central profile of a pair of scrolls are given and vari... A modification of central profile with trigonometric curve is proposed based on the theory of engagement of scroll compressor. General modification equations for central profile of a pair of scrolls are given and various modification patterns are discussed. The equidistant method is employed to calculate the volume of a sealed chamber and a set of general equations is represented. Modification parameters affecting geometric and dynamic property of a scroll compressor are analyzed systematically, and the relations between them are accurately determined. The condition for transforming a trigonometric curve modification into an arc-curve modification is explained. The conclusions can also be applied to other scroll fluid machines. 展开更多
关键词 Scroll profile modification Trigonometric curve Geometric dynamic
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Damping modification factors for acceleration response spectra 被引量:5
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作者 Heng Li Feng Chen 《Geodesy and Geodynamics》 2017年第5期361-370,共10页
DMF (Damping modification factors) are used to modify elastic response spectral values corresponding to damping ratio 5% to other damping levels. The influence of seismological parameters (magnitude, epicentral dis... DMF (Damping modification factors) are used to modify elastic response spectral values corresponding to damping ratio 5% to other damping levels. The influence of seismological parameters (magnitude, epicentral distances and site conditions) on DMF for acceleration spectra was analysed. The results show that for a given period as the magnitude or distance increase, the effect of damping on the seismic response will also increase, which indicates the response reduction from the structural damping will become more efficient. In the near-field of small earthquakes, the influence of site conditions on DMF is obvious, but it does not show a consistent rule. Furthermore, the DMF corresponding to different site conditions gradually close to unity with increasing magnitude and distance. The influence of the above mentioned parameters is related to the relative attenuation of the frequency components of the ground motion. The attenuation index alone is sufficient to take into account the influence. Based on these features, this paper roDoses a formula of DMF for acceleration response spectra. 展开更多
关键词 Damping modification factorsAcceleration response spectraSeismic codesAttenuation index
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Internal modification in transparent hybrid germanium-silica plates using plasma formation induced by a femtosecond laser 被引量:1
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作者 Ji-Wook YOON Jung-Kyu PARK +2 位作者 Kwang-Ho KIM Myung-Chang KANG Sung-Hak CHO 《中国有色金属学会会刊:英文版》 CSCD 2012年第S3期808-812,共5页
The fabrication of an internal diffraction grating with photoinduced refractive index modification in planar hybrid germanium-silica plates was demonstrated using low-density plasma formation excited by a high-intensi... The fabrication of an internal diffraction grating with photoinduced refractive index modification in planar hybrid germanium-silica plates was demonstrated using low-density plasma formation excited by a high-intensity femtosecond (150 fs) Ti:sapphire laser (λp=790 nm).The refractive index modifications with diameters ranging from 400 nm to 3 μm were photoinduced after plasma formation occurred upon irradiation with peak intensities of more than 2×1013 W/cm2.The graded refractive index profile was fabricated to be a symmetric around from the center of the point at which low-density plasma occurred. 展开更多
关键词 diffraction grating refractive index modification plasma formation HYBRID germanium-silica plate FEMTOSECOND laser
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Model Simplification and Parameter Modification for Offshore Platforms Using Experiment Data
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作者 Xu, Bin Tian, Qianli 《China Ocean Engineering》 SCIE EI 1993年第2期157-166,共10页
In this paper, a computation method has been developed so as to compare the finite element method (FEM) with the test results directly. The structure is divided into the 'master' and 'slave' degrees of... In this paper, a computation method has been developed so as to compare the finite element method (FEM) with the test results directly. The structure is divided into the 'master' and 'slave' degrees of freedom. The simplified model can be obtained with modal reduction. Then the design sensitivity analysis of the eigenvalues and eigenvectors has been carried out using the modal frequency and modal shape of the test. A two-story frame structure and a jacket model structure have been calculated. Meanwhile, the modified coefficient, the FEM computational and experimental values have been given. It has been shown that the FEM model modified using the test modal value is efficient. 展开更多
关键词 Degrees of freedom (mechanics) dynamics Eigenvalues and eigenfunctions Finite element method Mathematical models Model structures modification Sensitivity analysis
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Modification of short-range repulsive interactions in ReaxFF reactive force field for Fe–Ni–Al alloy
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作者 Huaqiang Chen Lin Lang +7 位作者 Shuaiyu Yi Jinlong Du Guangdong Liu Lixia Liu Yufei Wang Yuehui Wang Huiqiu Deng Engang Fu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期113-119,共7页
The short-range repulsive interactions of any force field must be modified to be applicable for high energy atomic collisions because of extremely far from equilibrium state when used in molecular dynamics(MD)simulati... The short-range repulsive interactions of any force field must be modified to be applicable for high energy atomic collisions because of extremely far from equilibrium state when used in molecular dynamics(MD)simulations.In this work,the short-range repulsive interaction of a reactive force field(ReaxFF),describing Fe-Ni-Al alloy system,is well modified by adding a tabulated function form based on Ziegler-Biersack-Littmark(ZBL)potential.The modified interaction covers three ranges,including short range,smooth range,and primordial range.The short range is totally predominated by ZBL potential.The primordial range means the interactions in this range is the as-is ReaxFF with no changes.The smooth range links the short-range ZBL and primordial-range ReaxFF potentials with a taper function.Both energies and forces are guaranteed to be continuous,and qualified to the consistent requirement in LAMMPS.This modified force field is applicable for simulations of energetic particle bombardments and reproducing point defects'booming and recombination effectively. 展开更多
关键词 molecular dynamics force field modification Fe–Ni–Al alloy irradiation
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Advanced surface engineering of titanium materials for biomedical applications:From static modification to dynamic responsive regulation 被引量:5
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作者 Pinliang Jiang Yanmei Zhang +6 位作者 Ren Hu Bin Shi Lihai Zhang Qiaoling Huang Yun Yang Peifu Tang Changjian Lin 《Bioactive Materials》 SCIE CSCD 2023年第9期15-57,共43页
Titanium(Ti)and its alloys have been widely used as orthopedic implants,because of their favorable mechanical properties,corrosion resistance and biocompatibility.Despite their significant success in various clinical ... Titanium(Ti)and its alloys have been widely used as orthopedic implants,because of their favorable mechanical properties,corrosion resistance and biocompatibility.Despite their significant success in various clinical applications,the probability of failure,degradation and revision is undesirably high,especially for the patients with low bone density,insufficient quantity of bone or osteoporosis,which renders the studies on surface modification of Ti still active to further improve clinical results.It is discerned that surface physicochemical properties directly influence and even control the dynamic interaction that subsequently determines the success or rejection of orthopedic implants.Therefore,it is crucial to endow bulk materials with specific surface properties of high bioactivity that can be performed by surface modification to realize the osseointegration.This article first reviews surface characteristics of Ti materials and various conventional surface modification techniques involving mechanical,physical and chemical treatments based on the formation mechanism of the modified coatings.Such conventional methods are able to improve bioactivity of Ti implants,but the surfaces with static state cannot respond to the dynamic biological cascades from the living cells and tissues.Hence,beyond traditional static design,dynamic responsive avenues are then emerging.The dynamic stimuli sources for surface functionalization can originate from environmental triggers or physiological triggers.In short,this review surveys recent developments in the surface engineering of Ti materials,with a specific emphasis on advances in static to dynamic functionality,which provides perspectives for improving bioactivity and biocompatibility of Ti implants. 展开更多
关键词 Titanium materials Orthopedic implants Bioactivity Static modification dynamic responsive regulation
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Dynamic response of buildings under debris flow impact
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作者 LIU Huan FAN Xiaoyi +1 位作者 TIAN Shujun DENG Xin 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1581-1597,共17页
This study employs the smoothed particle hydrodynamics–finite element method(SPH–FEM) coupling numerical method to investigate the impact of debris flow on reinforced concrete(RC)-frame buildings. The methodology co... This study employs the smoothed particle hydrodynamics–finite element method(SPH–FEM) coupling numerical method to investigate the impact of debris flow on reinforced concrete(RC)-frame buildings. The methodology considers the variables of debris flow depth and velocity and introduces the intensity index IDV(IDV = DV) to evaluate three different levels of debris flow impact intensity. The primary focus of this study is to investigate the dynamic response and failure mechanism of RC-frame buildings under debris flow impact, including structural failure patterns, impact force and column displacement. The results show that under a highintensity impact, a gradual collapse process of the RCframe building can be observed, and the damage mode of the frame column reflects shear failure or plastic hinge failure mechanism. First, the longitudinal infill walls are damaged owing to their low out-of-plane flexural capacity;the critical failure intensity index IDV value is approximately 7.5 m2/s. The structure cannot withstand debris flows with an intensity index IDV greater than 16 m2/s, and it is recommended that the peak impact force should not exceed 2100 k N. The impact damage ability of debris flow on buildings mostly originates from the impact force of the frontal debris flow, with the impact force of the debris flow body being approximately 42% lower than that of the debris flow head. Finally, a five-level classification system for evaluating the damage status of buildings is proposed based on the numerical simulation and investigation results of the disaster site. 展开更多
关键词 SPH–FEM method Debris flow BUILDINGS The intensity index dynamic response
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Study on Ecological Change Remote Sensing Monitoring Method Based on Elman Dynamic Recurrent Neural Network
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作者 Zhen Chen Yiyang Zheng 《Journal of Geoscience and Environment Protection》 2024年第4期31-44,共14页
In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to t... In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to the opening up, economic prosperity and social stability of Northeast China. In this paper, the remote sensing ecological index (RSEI) of Hailin City in recent 20 years was calculated by using Landsat 5/8/9 series satellite images, and the temporal and spatial changes of the ecological environment in Hailin City were further analyzed and the influencing factors were discussed. From 2003 to 2023, the mean value of RSEI in Hailin City decreased and increased, and the ecological environment decreased slightly as a whole. RSEI declined most significantly from 2003 to 2008, and it increased from 2008 to 2013, decreased from 2013 to 2018, and increased from 2018 to 2023 again, with higher RSEI value in the south and lower RSEI value in the northwest. It is suggested to appropriately increase vegetation coverage in the northwest to improve ecological quality. As a result, the predicted value of Elman dynamic recurrent neural network model is consistent with the change trend of the mean value, and the prediction error converges quickly, which can accurately predict the ecological environment quality in the future study area. 展开更多
关键词 Remote Sensing Ecological index Long Time Series Space-Time Change Elman dynamic Recurrent Neural Network
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Dynamic modifications of biomacromolecules: mechanism and chemical interventions 被引量:3
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作者 Chu Wang Peng Zou +7 位作者 Caiguang Yang Lei Liu Liang Cheng Xiaopeng He Liang Zhang Yan Zhang Hualiang Jiang Peng RChen 《Science China(Life Sciences)》 SCIE CAS CSCD 2019年第11期1459-1471,共13页
Biological macromolecules(proteins,nucleic acids,polysaccharides,etc.)are the building blocks of life,which constantly undergo chemical modifications that are often reversible and spatial-temporally regulated.These dy... Biological macromolecules(proteins,nucleic acids,polysaccharides,etc.)are the building blocks of life,which constantly undergo chemical modifications that are often reversible and spatial-temporally regulated.These dynamic properties of chemical modifications play fundamental roles in physiological processes as well as pathological changes of living systems.The Major Research Project(MRP)funded by the National Natural Science Foundation of China(NSFC)—"Dynamic modifications of biomacromolecules:mechanism and chemical interventions"aims to integrate cross-disciplinary approaches at the interface of chemistry,life sciences,medicine,mathematics,material science and information science with the following goals:(i)developing specific labeling techniques and detection methods for dynamic chemical modifications of biomacromolecules,(ii)analyzing the molecular mechanisms and functional relationships of dynamic chemical modifications of biomacromolecules,and(iii)exploring biomacromolecules and small molecule probes as potential drug targets and lead compounds. 展开更多
关键词 CHEMICAL BIOLOGY BIOMACROMOLECULE dynamic modification modification analysis CHEMICAL INTERVENTION
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Modification of PAE-degrading Esterase(CarEW)for Higher Degradation Efficiency Through Integrated Homology Modeling,Molecular Docking,and Molecular Dynamics Simulation
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作者 ZHOU Mengying LI Yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2022年第6期1400-1413,共14页
Six phthalate acid esters(PAEs)priority pollutants[dimethyl phthalate(DMP),diethyl phthalate(DEP),dibutyl phthalate(DBP or DNBP),di-n-octyl phthalate(DNOP),di 2-ethyl hexyl phthalate(DEHP),and butyl benzyl phthalate(B... Six phthalate acid esters(PAEs)priority pollutants[dimethyl phthalate(DMP),diethyl phthalate(DEP),dibutyl phthalate(DBP or DNBP),di-n-octyl phthalate(DNOP),di 2-ethyl hexyl phthalate(DEHP),and butyl benzyl phthalate(BBP)]were opted as the research object.PAE-degrading esterase CarEW(PDB ID:1C7I)isolated from Bacillus subtilis acting as a template and an iterative saturation mutation strategy was adopted to modify key amino acids to attain efficient PAE-degrading esterase substitutes with a reasonable structure constructed by homology modeling method.Present study designed a total of 285 unit-site and multi-site substitutions of PAE-degrading esterase using the homology modeling method.Among them,207 PAE-degrading esterase substitutions,which contained the 6-site PAE-degrading esterase substitute 1C7I-6-9 with 84.21%enhancement intensity of degradation ability revealed better degradability to all the 6 PAEs after modification.Moreover,molecular dynamics simulation based on the Taguchi method reported the optimal external application environment for PAE-degrading esterase substitutes as follows:pH=6,T=35℃,the rhamnolipid concentration was 50 mg/L,the molar ratio of nitrogen to phosphorus(N:P)was 10:1,the concentration of H2O_(2) was 50 mg/L,and the voltage gradient was 1.5 V/cm.The degradation ability of PAE-degrading esterase substitutes was found to be elevated by 13.04%as compared to that of the blank control under the optimal condition.Moreover,11 highly efficient PAE-degrading esterase substitutes with thermal stability were designed. 展开更多
关键词 Phthalate acid ester(PAE) PAE-degrading esterase Enzymatic modification Homology modeling Molecular docking Molecular dynamics simulation
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Effects of terminal modification on the catalytic efficiency and thermostability of Brucella melitensis 7α‑hydroxysteroid dehydrogenase
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作者 Zhiyong Liu Rongzhen Zhang +1 位作者 Wenchi Zhang Yan Xu 《Systems Microbiology and Biomanufacturing》 EI 2023年第3期469-478,共10页
Brucella melitensis 7α-hydroxysteroid dehydrogenase(Bm7α-HSDH)catalyzes the oxidation of chenodeoxycholic acid to 7-oxolithocholic acid.In this work,we investigated the effects of terminal modification(His-tags loca... Brucella melitensis 7α-hydroxysteroid dehydrogenase(Bm7α-HSDH)catalyzes the oxidation of chenodeoxycholic acid to 7-oxolithocholic acid.In this work,we investigated the effects of terminal modification(His-tags location and terminal truncation)on its catalytic efficiency and thermostability.Compared with C-terminal His-tagged Bm7α-HSDH(C-Bm7α-HSDH),N-Bm7α-HSDH showed a 3.6-fold higher kcat and a 1.3-fold lower Km,resulting in a 7.0-fold higher kcat/Km value toward chenodeoxycholic acid.Circular dichroism spectroscopy indicated that the melting temperature of N-Bm7α-HSDH(46.13℃)was 3.0℃lower than that of C-Bm7α-HSDH(49.13℃).N-Bm7α-HSDH produced 7-oxolithocholic acid in the highest yield of 96.7%in 4 h,whereas the C-Bm7α-HSDH gave 96.4%in 10 h.Moreover,amino acids truncation and His-tag cleave experiments confirmed the C-terminal residues played key roles in catalytic functions.Molecular dynamics simulations further indicated C-terminal His-tagged modification could deform the substrate-binding region to disrupt the enzyme–substrate interactions and catalytic motion.However,the N-terminal His-tag hardly affected the catalytic efficiency due to its location far from the active site of the enzyme.This study provides structural insights into the terminus modifications of hydroxysteroid dehydrogenase on steroid substrate recognition and stabilization,thus affecting its catalytic functions. 展开更多
关键词 Terminal modification 7α-hydroxysteroid dehydrogenase Catalytic efficiency Thermostability Molecular dynamics simulations
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Numerical investigation of basic oxygen furnace slag modification with gas bottom-blowing and SiO_(2) modifier
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作者 Chang Liu Yu-feng Tian +4 位作者 Yong-li Xiao Yong-qian Li Yang Li Guang-qiang Li Qiang Wang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2023年第7期1451-1460,共10页
To avoid the volume expansion of basic oxygen furnace (BOF) slag for use in building materials, a hot slag modification process was proposed to reduce free CaO (f-CaO) in the molten slag. A transient 3D numerical mode... To avoid the volume expansion of basic oxygen furnace (BOF) slag for use in building materials, a hot slag modification process was proposed to reduce free CaO (f-CaO) in the molten slag. A transient 3D numerical model of BOF molten slag modification by SiO_(2) particles was established. The flow and heat transfer of molten slag, movement and dissolution of the modifier, and concentration distribution of f-CaO in slag during the modification of BOF were studied. The distribution of f-CaO concentration is inhomogeneous all over the molten slag. The mixing effect at the slag surface is weaker than that at the half-height plane of the slag. To consume the f-CaO below 2.0 wt.% in the slag, the optimum quantity of the SiO_(2) modifier is 10.0% of the mass of the slag. The fine SiO_(2) particles help attain a lower final mass fraction of f-CaO and a higher SiO_(2) utilization ratio. 展开更多
关键词 Basic oxygen furnace slag modification SiO_(2)modifier Free CaO Discrete phase model Computational fluid dynamics
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The Dynamic Plateau Monsoon Index and Its Association with General Circulation Anomalies 被引量:18
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作者 荀学义 胡泽勇 马耀明 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第6期1249-1263,共15页
Based on monthly ECMWF reanalysis-Interim (ERA-Interim) reanalysis data, along with monthly precipitation and temperature data, the Dynamic Plateau Monsoon Index (DPMI) is defined. The results of a contrast analys... Based on monthly ECMWF reanalysis-Interim (ERA-Interim) reanalysis data, along with monthly precipitation and temperature data, the Dynamic Plateau Monsoon Index (DPMI) is defined. The results of a contrast analysis of the DPMI versus the Traditional Plateau Monsoon Index (TPMI) are described. The response of general circulation to northern Qinghai-Xizang Plateau summer monsoon anomalies and the correlation of the DPMI with general circulation anomalies are investigated. The results show that, the DPMI reflected meteorological elements better and depicted climate variation more accurately than the TPMI. In years when the plateau summer monsoon is strong, the low over the plateau and the trough near the eastern coast of Asia are deeper and higher than normal over South China. This correlation corresponds to two anomalous cyclones over the plateau and the eastern coast of Asia and an anomalous anticyclone in South China. The plateau and its adjacent regions are affected by anomalous southwesterly winds that transport more moisture to South China and cause more precipitation. The lower reaches of the Yangtze River appear to receive more precipitation by means of the strong westerly water vapor flow transported from the "large triangle affecting the region". In years when the plateau summer monsoon is weak, these are opposite. The plateau monsoon is closely related to the intensity and position of the South Asian high, and the existence of a teleconnection pattern in the mid-upper levels suggests a possible linkage of the East Asian monsoon and the Indian monsoon to the plateau summer monsoon. 展开更多
关键词 Qinghai-Xizang Plateau dynamic Plateau Monsoon index center position general circulation
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Predictive Values of Postoperative and Dynamic Changes of Inflammation Indexes in Survival of Patients with Resected Colorectal Cancer 被引量:11
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作者 Zi-quan ZHOU Shuo PANG +4 位作者 Xing-chen YU Qi XUE Hong-yu JIANG Xin-jun LIANG Li LIU 《Current Medical Science》 SCIE CAS 2018年第5期798-808,共11页
The aim of the present study was to evaluate the prognostic potential of postoperative scores of inflammation indexes and the dynamic changes of scores before and after tumor resection in colorectal cancer patients.Th... The aim of the present study was to evaluate the prognostic potential of postoperative scores of inflammation indexes and the dynamic changes of scores before and after tumor resection in colorectal cancer patients.The study included 516 colorectal cancer patients with primary colorectal tumor resection.Cox regression was applied to estimate the associations of postoperative and dynamic changes of inflammation indexes with progression-free survival and overall survival.As results,we found that higher postoperative neutrophil to lymphocyte ratio (NLR),neutrophil and monocyte to lymphocyte ratio (NMLR),platelet to lymphocyte ratio (PLR) and systemic immune inflammation index (SII)were associated with shorter progression-free survival.The increased NLR,NMLR,PLR,SII and C-reaction protein (CRP)to albumin (ALB) ratio (CAR)were associated with poor progression-free survival,with HRs (95% CIs)of 1.92 (1.27-2.90),1.46(1.11-2.09),2.10(1.34-3.30),1.81(1.22-2.70)and 1.65(1.03-2.67), respectively.Postoperative NMLR,SII,CAR,and their dynamic changes were also significantly correlated with overall survival,with the HRs (95% CIs)of 2.63(1.30-3.97), 2.44(1.43-4.17),2.74(1.31-5.74),2.08(1.21-3.60),1.97(1.12-3.45)and 2.55(1.21-5.38)respectively.In conclusion,postoperative inflammation indexes and their dynamic changes,particularly for NMLR,SII and CAR are promising prognostic predictors of CRC patients. 展开更多
关键词 COLORECTAL cancer POSTOPERATIVE INFLAMMATION index dynamic change PROGNOSIS
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DYNAMIC RESPONSE OF ROLLER GEAR INDEXING CAM SYSTEM CONSIDERING CLEARANCE AND MOTOR CHARACTERISTIC 被引量:4
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作者 Chang Zongyu Civil Aviation College,Nanjing University of Aeronautics and Astronautics Zhang Ce Yang Yuhu Wang Yuxin Tianjin University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期189-192,共4页
The dynamic responses of roller gear indexing cam mechanism are investigated .With applying Lagarange equation and Gear method,motion equations of this mechanism including clearance,motor characteristic,torsion flexib... The dynamic responses of roller gear indexing cam mechanism are investigated .With applying Lagarange equation and Gear method,motion equations of this mechanism including clearance,motor characteristic,torsion flexibility are developed and solved.The results show that clearance affects primarily the response on turret,and has little effects on the responses on rotary table.At the same time,the velocity fluctuation of motor shaft is not serious for the existence of inertia of reducer,and the high frequency of velocity fluctuation of camshaft is related with the torsion stiffness of shaft and the clearance between pairs. 展开更多
关键词 Roller gear indexing cam mechanism CLEARANCE Motor characteristic dynamic response
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Population dynamics and condition index of natural stock of blood cockle,Tegillarca granosa(Mollusca,Bivalvia,Arcidae)in the Marudu Bay,Malaysia
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作者 Joanna W.Doinsing Vienna Anastasia Admodisastro +1 位作者 Laditah Duisan Julian Ransangan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第8期89-97,共9页
The population parameters of blood cockles,Tegillarca granosa in the intertidal zone of Marudu Bay,Sabah,Malaysia were investigated based on monthly length-weight frequency data(July 2017 to June 2018).A total of 279 ... The population parameters of blood cockles,Tegillarca granosa in the intertidal zone of Marudu Bay,Sabah,Malaysia were investigated based on monthly length-weight frequency data(July 2017 to June 2018).A total of 279 cockle individuals with shell length and weight ranging from 27.7 mm to 82.2 mm and 13.11 g to 192.7 g were subjected to analysis.T.granosa in Marudu Bay showed a consistent moderately high condition index 4.98±0.86 throughout the year.The exponent b of the length-weight relationship was 2.6 demonstrating negative allometric growth.The estimated asymptotic length(L_(∞)),growth coefficient(K)and growth performance(Ф)of the T.granosa population in Marudu Bay were estimated at 86.68 mm,0.98 a^(-1) and 3.87,respectively.The observed maximum shell length was 82.55 mm and the predicted maximum shell length was 84.44 mm with estimated maximum life span(t_(max))of 3.06 years.The estimated mean lengths at the end of 2,4,6,8,10 and 12 months of age were 21.31 mm,31.16 mm,39.53 mm,46.63 mm,52.67 mm and 57.79 mm.Total,natural,and fishing mortalities were estimated at 2.39 a^(-1),1.32 a^(-1) and 1.07 a^(-1).The exploitation level(E)was 0.45.Results of the current study also demonstrated that T.granosa in the Marudu Bay has two major recruitment peaks;one in March and another in October.The exploitation level revealed that natural stock of T.granosa in the Marudu Bay was approaching the maximum exploitation level.If such trend continues or demand for T.granosa is increasing,coupled with no effective fisheries management in place,possibility of the T.granosa population in the Marudu Bay to collapse is likely to elevate. 展开更多
关键词 Arcidae population dynamics condition index Marudu Bay
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