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Real-World Evidence in Localized Pancreatic: Coping with Uncertainty in Unselected Populations
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作者 María I. Pamies Ramón Diana Ibarra Anguita +8 位作者 Paula Rodríguez Payá Alvaro Muñoz Abad David Sánchez García María Valero Revert Beatriz Grau Mirete Mariano Martínez Marín Alicia Calero Amaro Lorena Rodríguez Cazalla Javier Gallego Plazas 《Journal of Cancer Therapy》 2024年第4期164-178,共15页
Background: Localized pancreatic cancer, including resectable (R), borderline resectable (BR) and locally advanced unresectable disease (LAU), is considered in clinical guidelines for diverse treatment options based o... Background: Localized pancreatic cancer, including resectable (R), borderline resectable (BR) and locally advanced unresectable disease (LAU), is considered in clinical guidelines for diverse treatment options based on clinical trials in selected populations. Hence, exploring with real world evidence (RWE) clinicians’ preferences for treatment options and their results seems pertinent. Methods: In a set of consecutive patients with localized pancreatic cancer assisted in a third level hospital from January 2013 to December 2022, medical records, symptoms, diagnostic process, distribution between subtypes, and treatment plans, with safety and efficacy results, were assessed. Results: A total of 152 patients with localized disease were included (43.4% R, 21.0% BR, 33.6% LAU). The population characteristics exemplified differences between daily practice and clinical trials. Tumor location and symptoms were as expected. Treatment plan was conditioned by PS or comorbidities in 23.0% of patients. In patients with R disease, surgery followed by different adjuvant chemotherapy (CT) regimes was the antineoplastic treatment of choice (64.8%) with efficacy results (OS 37.5 months;95% CI 18.4 - 56.7), in the range of contemporary standards. The common use of neoadjuvant CT for BR disease (94.4%), with surgery in 50% of them, and its results (OS 30.8 months;95% CI 10.5 - 51.2) reflected current controversies of treatment recommendations and evolution in this scenario. Paliative CT with or without radiotherapy was the standard specific treatment in LAU disease (95.1%) with survival results (PFS: 10.8 months;95% CI 8.8 - 12.7. OS: 20.3 months;95% CI 13.5 - 27.2) that justify the distinct character and the specific study of this entity. Conclusion: RWE for localized pancreatic cancer aroused from the analysis of this population confirms the distinct nature of patients assisted in daily practice, as well as mirrors the complexity of decision making in clinical assumptions in which achieving stronger evidence should be paramount. 展开更多
关键词 Real-World Evidence localized PANCREATIC CANCER
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In-situ AFM and quasi-in-situ studies for localized corrosion in Mg-9Al-1Fe-(Gd) alloys under 3.5 wt.% NaCl environment
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作者 Junping Shen Tao Lai +7 位作者 Zheng Yin Yang Chen Kun Wang Hong Yan Honggun Song Ruiliang Liu Chao Luo Zhi Hu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1170-1185,共16页
Revealing the localized corrosion process of Mg alloy is considered as one of the most significant ways for improving its corrosion resistance.The reliable monitor should be high distinguishability and real-time in li... Revealing the localized corrosion process of Mg alloy is considered as one of the most significant ways for improving its corrosion resistance.The reliable monitor should be high distinguishability and real-time in liquid environment.Herein,Mg-9Al-1Fe and Mg-9Al-1Fe-1Gd alloys were designed to highlight the impact of intermetallic on the corrosion behaviour.In-situ AFM with a special electrolyte circulation system and quasi-in-situ SEM observation were used to monitor the corrosion process of the designed alloys.SEM-EDS and TEM-SAED were applied to identify the intermetallic in the designed alloys,and their volta potentials were measured by SKPFM.According to the real-time and real-space in-situ AFM monitor,the corrosion process consisted of dissolution of anodicα-Mg phase,accumulation of corrosion products around cathodic phase and shedding of some fine cathodic phase.Then,the localized corrosion process of Mg alloy was revealed combined with the results of the monitor of corrosion process and Volta potential difference. 展开更多
关键词 Magnesium localized corrosion In-situ AFM SKPFM Corrosion behaviour.
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Facilitating prelithiation of silicon carbon anode by localized high-concentration electrolyte for high-rate and long-cycle lithium storage
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作者 Yuanxing Zhang Borong Wu +6 位作者 Jiaying Bi Xinyu Zhang Daobin Mu Xin-Yu Zhang Ling Zhang Yao Xiao Feng Wu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期216-233,共18页
The commercialization of silicon-based anodes is affected by their low initial Coulombic efficiency(ICE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)layer.Her... The commercialization of silicon-based anodes is affected by their low initial Coulombic efficiency(ICE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)layer.Herein,a feasible and cost-effective prelithiation method under a localized highconcentration electrolyte system(LHCE)for the silicon-silica/graphite(Si-SiO_(2)/C@G)anode is designed for stabilizing the SEI layer and enhancing the ICE.The thin SiO_(2)/C layers with-NH_(2) groups covered on nano-Si surfaces are demonstrated to be beneficial to the prelithiation process by density functional theory calculations and electrochemical performance.The SEI formed under LHCE is proven to be rich in ionic conductivity,inorganic substances,and flexible organic products.Thus,faster Li+transportation across the SEI further enhances the prelithiation effect and the rate performance of Si-SiO_(2)/C@G anodes.LHCE also leads to uniform decomposition and high stability of the SEI with abundant organic components.As a result,the prepared anode shows a high reversible specific capacity of 937.5 mAh g^(-1)after 400 cycles at a current density of 1 C.NCM 811‖Li-SSGLHCE full cell achieves a high-capacity retention of 126.15 mAh g^(-1)at 1 C over 750 cycles with 84.82%ICE,indicating the great value of this strategy for Si-based anodes in large-scale applications. 展开更多
关键词 localized high-concentration electrolytes prelithiation SEI layer silicon anode
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Observation of flat-band localized state in a one-dimensional diamond momentum lattice of ultracold atoms
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作者 曾超 石悦然 +5 位作者 毛一屹 武菲菲 谢岩骏 苑涛 戴汉宁 陈宇翱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期212-217,共6页
We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on th... We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on the diamond model, precisely controlling the coupling strength and phase between individual lattice sites. Utilizing two lattice sites couplings, we generated a compact localized state associated with the flat band, which remained localized throughout the entire time evolution. We successfully realized the continuous shift of flat bands by adjusting the corresponding nearest neighbor hopping strength, enabling us to observe the complete localization process. This opens avenues for further exploration of more complex properties within flat-band systems, including investigating the robustness of flat-band localized states in disordered flat-band systems and exploring many-body localization in interacting flat-band systems. 展开更多
关键词 diamond lattice flat band momentum lattice localized state
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Evolution of mechanical properties,localized corrosion resistance and microstructure of a high purity Al-Zn-Mg-Cu alloy during non-isothermal aging
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作者 DAI Xuan-xuan LI Yu-zhang +2 位作者 LIU Sheng-dan YE Ling-ying BAO Chong-jun 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1790-1807,共18页
The evolution of mechanical properties,localized corrosion resistance of a high purity Al-Zn-Mg-Cu alloy during non-isothermal aging(NIA)was investigated by hardness test,electrical conductivity test,tensile test,inte... The evolution of mechanical properties,localized corrosion resistance of a high purity Al-Zn-Mg-Cu alloy during non-isothermal aging(NIA)was investigated by hardness test,electrical conductivity test,tensile test,intergranular corrosion test,exfoliation corrosion test,slow strain rate tensile test and electrochemical test,and the mechanism has been discussed based on microstructure examination by optical microscopy,electron back scattered diffraction,scanning electron microscopy and scanning transmission electron microscopy.The NIA treatment includes a heating stage from 40℃to 180℃with a rate of 20℃/h and a cooling stage from 180℃to 40℃with a rate of 10℃/h.The results show that the hardness and strength increase rapidly during the heating stage of NIA since the increasing temperature favors the nucleation and the growth of strengthening precipitates and promotes the transformation of Guinier-Preston(GPI)zones toη'phase.During the cooling stage,the sizes ofη'phase increase with a little change in the number density,leading to a further slight increase of the hardness and strength.As NIA proceeds,the corroded morphology in the alloy changes from a layering feature to a wavy feature,the maximum corrosion depth decreases,and the reason has been analyzed based on the microstructural and microchemical feature of precipitates at grain boundaries and subgrain boundaries. 展开更多
关键词 Al-Zn-Mg-Cu alloy non-isothermal aging mechanical properties localized corrosion resistance MICROSTRUCTURE
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Iterative Subregion Correction Preconditioners with Adaptive Tolerance for Problems with Geometrically Localized Stiffness
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作者 Michael Franco Per-Olof Persson Will Pazner 《Communications on Applied Mathematics and Computation》 EI 2024年第2期811-836,共26页
We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated problems.These preconditioners are designed to treat the ca... We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated problems.These preconditioners are designed to treat the case of geometrically localized stiffness,where the convergence rates of iterative methods are degraded in a localized subregion of the mesh.Slower convergence may be caused by a number of factors,including the mesh size,anisotropy,highly variable coefficients,and more challenging physics.The approach taken in this work is to correct well-known preconditioners such as the block Jacobi and the block incomplete LU(ILU)with an adaptive inner subregion iteration.The goal of these preconditioners is to reduce the number of costly global iterations by accelerating the convergence in the stiff region by iterating on the less expensive reduced problem.The tolerance for the inner iteration is adaptively chosen to minimize subregion-local work while guaranteeing global convergence rates.We present analysis showing that the convergence of these preconditioners,even when combined with an adaptively selected tolerance,is independent of discretization parameters(e.g.,the mesh size and diffusion coefficient)in the subregion.We demonstrate significant performance improvements over black-box preconditioners when applied to several model convection-diffusion problems.Finally,we present performance results of several variations of iterative subregion correction preconditioners applied to the Reynolds number 2.25×10^(6)fluid flow over the NACA 0012 airfoil,as well as massively separated flow at 30°angle of attack. 展开更多
关键词 Subregion correction Nested Krylov Geometrically localized stiffness
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Conditional Generative Adversarial Network Enabled Localized Stress Recovery of Periodic Composites
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作者 Chengkan Xu Xiaofei Wang +2 位作者 Yixuan Li Guannan Wang He Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期957-974,共18页
Structural damage in heterogeneousmaterials typically originates frommicrostructures where stress concentration occurs.Therefore,evaluating the magnitude and location of localized stress distributions within microstru... Structural damage in heterogeneousmaterials typically originates frommicrostructures where stress concentration occurs.Therefore,evaluating the magnitude and location of localized stress distributions within microstructures under external loading is crucial.Repeating unit cells(RUCs)are commonly used to represent microstructural details and homogenize the effective response of composites.This work develops a machine learning-based micromechanics tool to accurately predict the stress distributions of extracted RUCs.The locally exact homogenization theory efficiently generates the microstructural stresses of RUCs with a wide range of parameters,including volume fraction,fiber/matrix property ratio,fiber shapes,and loading direction.Subsequently,the conditional generative adversarial network(cGAN)is employed and constructed as a surrogate model to establish the statistical correlation between these parameters and the corresponding localized stresses.The stresses predicted by cGAN are validated against the remaining true data not used for training,showing good agreement.This work demonstrates that the cGAN-based micromechanics tool effectively captures the local responses of composite RUCs.It can be used for predicting potential crack initiations starting from microstructures and evaluating the effective behavior of periodic composites. 展开更多
关键词 Periodic composites localized stress recovery conditional generative adversarial network
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Recent trends and impact of localized surface plasmon resonance (LSPR) and surface-enhanced Raman spectroscopy (SERS) in modern analysis
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作者 Bibhu Prasad Nanda Priyanka Rani +3 位作者 Priyanka Paul Aman Subrahmanya S.Ganti Rohit Bhatia 《Journal of Pharmaceutical Analysis》 CSCD 2024年第11期1603-1624,共22页
An optical biosensor is a specialized analytical device that utilizes the principles of optics and light in bimolecular processes.Localized surface plasmon resonance(LSPR)is a phenomenon in the realm of nanophotonics ... An optical biosensor is a specialized analytical device that utilizes the principles of optics and light in bimolecular processes.Localized surface plasmon resonance(LSPR)is a phenomenon in the realm of nanophotonics that occurs when metallic nanoparticles(NPs)or nanostructures interact with incident light.Conversely,surface-enhanced Raman spectroscopy(SERS)is an influential analytical technique based on Raman scattering,wherein it amplifies the Raman signals of molecules when they are situated near specific and specially designed nanostructures.A detailed exploration of the recent groundbreaking developments in optical biosensors employing LSPR and SERS technologies has been thoroughly discussed along with their underlying principles and the working mechanisms.A biosensor chip has been created,featuring a high-density deposition of gold nanoparticles(AuNPs)under varying ligand concentration and reaction duration on the substrate.An ordinary description,along with a visual illustration,has been thoroughly provided for concepts such as a sensogram,refractive index shift,surface plasmon resonance(SPR),and the evanescent field,Rayleigh scattering,Raman scattering,as well as the electromagnetic enhancement and chemical enhancement.LSPR and SERS both have advantages and disadvantages,but widely used SERS has some advantages over LSPR,like chemical specificity,high sensitivity,multiplexing,and versatility in different fields.This review confirms and elucidates the significance of different disease biomarker identification.LSPR and SERS both play a vital role in the detection of various types of cancer,such as cervical cancer,ovarian cancer,endometrial cancer,prostate cancer,colorectal cancer,and brain tumors.This proposed optical biosensor offers potential applications for early diagnosis and monitoring of viral disease,bacterial infectious diseases,fungal diseases,diabetes,and cardiac disease biosensing.LSPR and SERS provide a new direction for environmental monitoring,food safety,refining impurities from water samples,and lead detection.The understanding of these biosensors is still limited and challenging. 展开更多
关键词 localized surface plasmon resonance Surface-enhanced Raman spectroscopy Nanophotonic Biosensors Nanoparticles BIOMARKER Cancer
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Navigating the pathways:TAR-DNA-binding-protein-43 aggregation,axonal transport,and local synthesis in amyotrophic lateral sclerosis pathology
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作者 Ori Bar Avi Eran Perlson 《Neural Regeneration Research》 SCIE CAS 2025年第10期2921-2922,共2页
Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and m... Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and metabolic events,which need to be carried out at the right place,time,and intensity.Such mechanisms include axonal transport,local synthesis,and liquid-liquid phase separations.Alterations and malfunctions in these processes are correlated to neurodegenerative diseases such as amyotrophic lateral sclerosis(ALS). 展开更多
关键词 SYNTHESIS local AGGREGATION
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Localized Application of Chinese Standards in Jakarta-Bandung HSR Project
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作者 WANG Yanchen WANG Shujie SHEN Meiying(Translated) 《Chinese Railways》 2024年第1期13-22,共10页
Jakarta-Bandung HSR in Indonesia is the first“go global”project of China's high speed railway with a whole system,all elements and a whole industry chain,as well as the first overseas project adopting a complete... Jakarta-Bandung HSR in Indonesia is the first“go global”project of China's high speed railway with a whole system,all elements and a whole industry chain,as well as the first overseas project adopting a complete set of Chinese standards.This paper sorts out the differences between relevant standards in China and Indonesia,including those in concrete raw materials,rebar standards and other main material standards,and those in external interface standards,train operation direction requirements,project approval requirements,special acceptance requirements,etc.,and summarizes the realization methods and specific achievements of localized application of Chinese standards during the implementation of Jakarta-Bandung HSR Project,to provide reference for localized application of Chinese standards in overseas projects in the future. 展开更多
关键词 Jakarta-Bandung HSR Chinese standards localized application Indonesian standards overseas projects
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Reconfigurable exceptional point-based sensing with 0.001λsensitivity using spoof localized surface plasmons
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作者 Yaoran Zhang Hao Hu +4 位作者 Francisco JoséGarcía-Vidal Jingjing Zhang Liangliang Liu Yu Luo Zhuo Li 《Advanced Photonics Nexus》 2024年第5期58-66,共9页
Recent breakthroughs in the field of non-Hermitian physics present unprecedented opportunities,from fundamental theories to cutting-edge applications such as multimode lasers,unconventional wave transport,and high-per... Recent breakthroughs in the field of non-Hermitian physics present unprecedented opportunities,from fundamental theories to cutting-edge applications such as multimode lasers,unconventional wave transport,and high-performance sensors.The exceptional point,a spectral singularity widely existing in non-Hermitian systems,provides an indispensable route to enhance the sensitivity of optical detection.However,the exceptional point of the forementioned systems is set once the system is built or fabricated,and machining errors make it hard to reach such a state precisely.To this end,we develop a highly tunable and reconfigurable exceptional point system,i.e.,a single spoof plasmonic resonator suspended above a substrate and coupled with two freestanding Rayleigh scatterers.Our design offers great flexibility to control exceptional point states,enabling us to dynamically reconfigure the exceptional point formed by various multipolar modes across a broadband frequency range.Specifically,we experimentally implement five distinct exceptional points by precisely manipulating the positions of two movable Rayleigh scatterers.In addition,the enhanced perturbation strength offers remarkable sensitivity enhancement for detecting deep-subwavelength particles with the minimum dimension down to 0.001λ(withλto be the free-space wavelength). 展开更多
关键词 non-Hermitian optics spoof localized surface plasmons exceptional points ultrasensitive microwave sensors
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Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential
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作者 Jia Zhao Taixi Feng Guimin Lu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期439-449,共11页
The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La a... The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies. 展开更多
关键词 magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation
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Unveiling optical rogue wave behavior with temporally localized structures in Brillouin random fiber laser comb
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作者 Yuxi Pang Qiang Ji +6 位作者 Shaonian Ma Xian Zhao Zengguang Qin Zhaojun Liu Ping Lu Xiaoyi Bao Yanping Xu 《Advanced Photonics Nexus》 2024年第2期59-74,共16页
The optical rogue wave(RW),known as a short-lived extraordinarily high amplitude dynamics phenomenon with small appearing probabilities,plays an important role in revealing and understanding the fundamental physics of... The optical rogue wave(RW),known as a short-lived extraordinarily high amplitude dynamics phenomenon with small appearing probabilities,plays an important role in revealing and understanding the fundamental physics of nonlinear wave propagations in optical systems.The random fiber laser(RFL),featured with cavity-free and“modeless”structure,has opened up new avenues for fundamental physics research and potential practical applications combining nonlinear optics and laser physics.Here,the extreme event of optical RW induced by noise-driven modulation instability that interacts with the cascaded stimulated Brillouin scattering,the quasi-phase-matched four-wave mixing as well as the random mode resonance process is observed in a Brillouin random fiber laser comb(BRFLC).Temporal and statistical characteristics of the RWs concerning their emergence and evolution are experimentally explored and analyzed.Specifically,temporally localized structures with high intensities including chair-like pulses with a sharp leading edge followed by a trailing plateau appear frequently in the BRFLC output,which can evolve to chair-like RW pulses with adjustable pulse duration and amplitude under controlled conditions.This investigation provides a deep insight into the extreme event of RWs and paves the way for RW manipulation for its generation and elimination in RFLs through adapted laser configuration. 展开更多
关键词 optical rogue wave modulation instability random fiber laser cascaded stimulated Brillouin scattering four-wave mixing temporally localized structure
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Numerical and Experimental Study of Localized Lifetime Control LIGBT by High Dose He Ion Implantation 被引量:3
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作者 方健 唐新伟 +1 位作者 李肇基 张波 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第9期1048-1054,共7页
A high speed LIGBT with localized lifetime control by using high dose and low en ergy helium implantation(LC-LIGBT) is proposed.Compared with conventional LIGB Ts,particle irradiation results show that trade-off relat... A high speed LIGBT with localized lifetime control by using high dose and low en ergy helium implantation(LC-LIGBT) is proposed.Compared with conventional LIGB Ts,particle irradiation results show that trade-off relationship between turn- off time and forward voltage drop is improved.At the same time,the forward volta ge drop and turn-off time of such device are researched,when localized lifetime control region place near the p+-n junction,even in p+ anode.The results s how for the first time,helium ions,which stop in the p+ anode,also contribute to the forward voltage drop increasing and turn-off time reducing. 展开更多
关键词 LIGBT localized lifetime control helium ion implantation
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Research on Localized Design of Roof Garden
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作者 梅小清 吴鹏 黄筱 《Journal of Landscape Research》 2011年第4期4-5,9,共3页
The paper had studied localized design and construction of roof garden.Starting from the history of roof garden,it summarized development of roof garden.It was considered that roof garden could not only provide public... The paper had studied localized design and construction of roof garden.Starting from the history of roof garden,it summarized development of roof garden.It was considered that roof garden could not only provide public rest space,realize thermal insulation and noise reduction of architectures,help water-storage and urban drainage;but also beautify environment,ameliorate regional climate,enrich urban landscape,help to increase ground greening area and improve ecological quality.Finally,some designing principles for roof garden had been proposed,including ① enhancing security consciousness and highlighting roof load design;② emphasizing ecological use and stressing greening coverage;③ manifesting artistic feature;④ investing cautiously,saving construction cost and paying attention to later maintenance. 展开更多
关键词 Roofgarden Green SPACE ECOLOGICAL ENVIRONMENT localized DESIGN
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β-Amylase Is Predominantly Localized to Plastids in the Developing Tuberous Root of Sweet Potato 被引量:3
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作者 秦颖 王毅 +1 位作者 段长青 张大鹏 《Acta Botanica Sinica》 CSCD 2003年第5期581-588,共8页
Starch degradation in cells is closely associated with cereal seed germination, photosynthesis in leaves, carbohydrate storage in tuber and tuberous roots, and fleshy fruit development. Based on previously reported ... Starch degradation in cells is closely associated with cereal seed germination, photosynthesis in leaves, carbohydrate storage in tuber and tuberous roots, and fleshy fruit development. Based on previously reported in vitro assays, β amylase is considered as one of the key enzymes catalyzing starch breakdown, but up to date its role in starch breakdown in living cells remains unclear because the enzyme was shown often extrachloroplastic in living cells. Recently we have shown for the first time that β_amylase is predominantly immuno_localized to plastids in living cells of developing apple fruit. But it remains to know whether this model of β_amylase compartmentation is more widespread in plant living cells. The present experiment, conducted in tuberous root of sweet potato ( Ipomea batatas Lam. cv. Xushu 18) and via immunogold electron_microscopy technique, showed that β amylase visualized by gold particles was predominantly localized in plastids especially at periphery of starch granules, but the gold particles were scarcely found in other subcellular compartments, indicating that the enzyme is subcellularly compartmented in the same zone as its starch substrates. The density of gold particles (β amylase) in plastids was increasing during growing season, but the predominantly plastid_distributed pattern of β amylase in cells was shown unchanged throughout the tuberous root development. These data prove that the enzyme is compartmented in its functional sites, and so provide evidence to support the possible widespread biological function of the enzyme in catalyzing starch breakdown in plant living cells or at least in living cells of plant storage organs. 展开更多
关键词 AMYLASE subcellular localization sweet potato tuberous root PLASTID hydrolysis starch
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Microstructural Evolution of Localized Shear Bands Induced during Explosion in Ti-6Al-4V Alloy 被引量:7
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作者 YongboXU M.A.Mevers 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第5期385-387,共3页
Microstructures of the localized shear bands generated during explosion with a thick-walled cylinder specimen in Ti-6AI-4V alloy, were characterized by TEM and SEM. The results show that the twinning is a major mode o... Microstructures of the localized shear bands generated during explosion with a thick-walled cylinder specimen in Ti-6AI-4V alloy, were characterized by TEM and SEM. The results show that the twinning is a major mode of deformation, and the distortion-free grains in the bands with the size of 10μm in diameter were proposed to be the re-crystallization during dynamic explosion. The further observations show that the α→α2 phase transformation may occur in the bands, and this kind of transformation could be confirmed by its dark field image and electron diffraction analysis. Analysis shows that there is specified orientation between the α and α2 Phases. 展开更多
关键词 Shear localization Ti-alloy PHASE-TRANSFORMATION TWINNING
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Simulation on function mechanism of T1(Al_2CuLi) precipitate in localized corrosion of Al-Cu-Li alloys 被引量:10
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作者 李劲风 郑子樵 +3 位作者 任文达 陈文敬 赵旭山 李世晨 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2006年第6期1268-1273,共6页
To clarify the corrosion mechanism associated with the precipitate of T1(Al2CuLi)in Al-Li alloys,the simulated bulk precipitate of T1 was fabricated through melting and casting.Its electrochemical behavior and couplin... To clarify the corrosion mechanism associated with the precipitate of T1(Al2CuLi)in Al-Li alloys,the simulated bulk precipitate of T1 was fabricated through melting and casting.Its electrochemical behavior and coupling behavior with α(Al)in 3.5% NaCl solution were investigated.Meanwhile,the simulated Al alloy containing T1 particle was prepared and its corrosion morphology was observed.The results show that there exists a dynamic conversion corrosion mechanism associated with the precipitate of T1.At the beginning,the precipitate of T1 is anodic to the alloy base and corrosion occurs on its surface.However,during its corrosion process,its potential moves to a positive direction with immersion time increasing,due to the preferential dissolution of Li and the enrichment of Cu.As a result,the corroded T1 becomes cathodic to the alloy base at a later stage,leading to the anodic dissolution and corrosion of the alloy base at its adjacent periphery.It is suggested that the localized corrosion associated with the precipitate of T1 in Al-Li alloys is caused by the alternate anodic dissolution of the T1 precipitate and the alloy base at its adjacent periphery. 展开更多
关键词 AL-CU-LI ALLOY localized CORROSION mechanism T1(Al2CuLi)precipitate
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Perioperative complications of radical retropubic prostatectomy in patients with locally advanced prostate cancer: a comparison with clinically localized prostate cancer 被引量:3
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作者 Xu-Dong Yao Xiao-Jun Liu +3 位作者 Shi-Lin Zhang Bo Dai Hai-Liang Zhang Ding-Wei Ye 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第2期241-245,I0007,I0008,共7页
Radical prostatectomy (RP) continues to be an effective surgical therapy for prostate carcinoma, particularly for organ-confined prostate cancer (PCa). Recently, RP has also been used in the treatment of locally a... Radical prostatectomy (RP) continues to be an effective surgical therapy for prostate carcinoma, particularly for organ-confined prostate cancer (PCa). Recently, RP has also been used in the treatment of locally advanced prostate cancer. However, little research has been performed to elucidate the perioperative complications associated with RP in patients with clinically localized or locally advanced PCa. We sought to analyse the incidence of complications in these two groups after radical retropubic prostatectomy (RRP). From June 2002 to July 2010, we reviewed 379 PCa patients who underwent RRP in our hospital. Among these cases, 196 had clinically localized PCa (Tla-T2c group 1), and 183 had locally advanced PCa ( ≥ T3,: group 2). The overall complication incidence was 21.9%, which was lower than other studies have reported. Perioperative complications in patients with locally advanced PCa mirror those in patients with clinically localized PCa (26.2% vs. 17.8%, P=0.91). Our results showed that perioperative complications could not be regarded as a factor to consider in regarding RP in patients with cT3 or greater. 展开更多
关键词 COMPLICATIONS clinically localized prostate cancer locally advanced prostate cancer prostate cancer (PCa) prostatectomy radical retropubic prostatectomy (RRP)
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Folded localized excitations in the (2+1)-dimensional modified dispersive water-wave system 被引量:7
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作者 雷燕 马松华 方建平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期138-142,共5页
By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is de... By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is derived. Based on the derived solutions and using some multi-valued functions, we obtain some novel folded localized excitations of the system. 展开更多
关键词 mapping approach modified dispersive water-wave system solitary wave solution folded localized excitation
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