检索结果-南通市图书馆

Unilateral versus bilateral Y-type stent-in-stent metal stent insertions in inoperable malignant hilar biliary strictures:A multicenter retrospective study

引用

Hepatobiliary & Pancreatic Diseases International 2021年第6期20卷 561-567页

作者： Ik Hyun Jo Chang-Nyol Paik dae Bum kim Jaesin Lee Jong Yul Lee Jae Hyuck Chang Kyu-Hyun Paik won-Suk Park Department of Internal Medicine College of MedicineSt.Vincent’s HospitalThe Catholic University of KoreaSeoulKorea Department of Internal Medicine College of MedicineIncheon St.Mary’s HospitalThe Catholic University of KoreaSeoulKorea Department of Internal Medicine College of MedicineBucheon St.Mary’s HospitalThe Catholic University of KoreaSeoulKorea Department of Internal Medicine College of MedicineDaejeon St.Mary’s HospitalThe Catholic University of KoreaSeoulKorea

Background:To date,there is controversy regarding unilateral versus bilateral stent placement in patients with malignant hilar biliary strictures(MHBSs).The aim of this study was to compare the clinical outcomes and complications of unilateral and bilateral(stent-in-stent method)stent placements for these ***:We conducted a multicenter retrospective analysis of patients with inoperable MHBS who underwent endoscopic self-expandable metal stent(SEMS)placement from January 2009 to December *** groups classified according to the stent procedure method were compared for demographic,procedural,and postprocedure *** analysis for patency loss and overall survival was also ***:A total of 236 subjects were included.A superior technical success rate was found in the unilateral stent group(98.8%vs.82.5%,P<0.001),whereas the clinical success rate was higher in the bilateral group(85.7%vs.70.5%,P=0.028).There was no significant difference with respect to complications or patency loss,and the bilateral group had better overall survival(P<0.01).In the Cox proportional hazard model,MHBSs from lymph node compression were associated with a higher risk of death(HR=9.803,P=0.003).In contrast,bilateral SEMS insertion showed reduced postprocedural mortality(HR=0.316,P=0.001).Conclusions:Y-type stent-in-stent bilateral SEMSs are technically difficult but demonstrated more favorable overall survival for palliative bile drainage of inoperable MHBS patients compared to unilateral insertions.

关键词： Cholestasis Extrahepatic neoplasm Cholangiopancreatography Endoscopy Self-expandable metal stents

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ag-GST/HfO_(x)-based unidirectional threshold switching selector with low leakage current and threshold voltage distribution for high-density cross-point arrays

引用

Rare Metals 2024年第1期43卷 280-288页

作者： Kyoung-Joung Yoo dae-Yun Kang Nahyun kim Ho-Jin Lee Ta-Hyeong kim Taeho kim Tae Geun kim School of Electrical Engineering Korea UniversitySeoul 02841Republic of Korea

The use of electrochemical-metallization-based volatile threshold switching selectors in cross-point arrays has been widely explored owing to their high on-off ratios and simple ***,these devices are unsuitable for cross-point architectures because of the difficulty in controlling the random filament formation that results in large fluctuations in the threshold voltage during *** this study,we investigated the unidirectional threshold transition characteristics associated with an Ag/GST/HfO_(x)/Pt-based bilayer selector and demonstrated the occurrence of a low leakage current(<1×10^(-11) A) and low distribution of the threshold voltage(Δ0.11 V).The bilayer structure could control the filament formation in the intermediate state through the insertion of an HfO_(x) tunneling *** stacking a bilayer selector with NiO_(x)based resistive random-access memory,the leakage and programming currents of the device could be significantly *** the crossbar array configuration,we performed equivalent circuit analysis of a one-selector oneresistor(1S1R) devices and estimated the optimal array size to demonstrate the applicability of the proposed *** maximum acceptable crossbar array size of the 1S1R device with the Ag/GST/HfO_(x)/Pt/Ti/NiO_(x)/Pt structure was 5.29×10^(14)(N^(2),N=2.3×10^(7)).

关键词： Selector device Tunneling barrier Threshold switching Sputtering 1S1R Cross-point array

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Discovery of Zr-based metal-organic polygon:Unveiling new design opportunities in reticular chemistry

引用

Nano Research 2021年第2期14卷 392-397页

作者： Jiyeon kim Dongsik Nam Hiroshi Kitagawa dae-Woon Lim wonyoung Choe Department of Chemistry Ulsan National Institute of Science and Technology50 UNIST-gilUlsan 44919Republic of Korea Department of Chemistry Graduate School of ScienceKyoto UniversityKitashirakawa Oiwake-choSakyo-kuKyoto 606-8502Japan Department of Chemistry and Medical Chemistry College of Science and TechnologyYonsei University1 Yonseidae-gilWonjuGangwon-do 26493Republic of Korea

Metal-based secondary building unit and the shape of organic ligands are the two crucial factors for determining the final topology of metal-organic materials.A careful choice of organic and inorganic structural building units occasionally produces unexpected structures,facilitating deeper fundamental understanding of coordination-driven self-assembly behind metal-organic ***,we have synthesized a triangular metal-organic polygon(MOT-1),assembled from bulky tetramethyl terephthalate and Zr-based secondary building ***,the Zr-based secondary building unit serves as an unusual ditopic Zr-connector,toform metal-organic polygon MOT-1,proven to be a good candidate for water adsorption with *** study highlights the interplay of the geometrically frustrated ligand and secondary building unit in controlling the connectivity of metal-organic *** a strategy can be further used to unveil a new class of metal-organic materials.

关键词： reticular chem istry Zr-based metal-organic polygon geometrical frustration ditopic secondary building unit

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Direct interaction of DNMT inhibitors to PrP^C suppresses pathogenic process of prion

引用

Acta Pharmaceutica Sinica B 2019年第5期9卷 952-959页

作者： dae-Hwan kim Chunyan Ren Chongsuk Ryou Jiaojie Li Institute of Pharmaceutical Science and Technology Hanyang UniversityAnsan15588Republic of Korea School of Undergraduate Studies College of Transdisciplinary StudiesDaegu Gyeongbuk Institute of Science and TechnologyDaegu42988Republic of Korea Boston Children’s Hospital Harvard Medical SchoolBostonMA02115USA Department of Pharmacy Hanyang UniversityAnsan15588Republic of Korea Department of Chemistry Gwangju Institute of Science and TechnologyGwangju61005Republic of Korea

The conversion of the normal cellular prion protein(PrP^C) to the misfolded pathogenic scrapie prion protein(Pr PSc) is the biochemical hallmark of prion replication. So far, various chemical compounds that inhibit this conformational conversion have been identified. Here, we report the novel anti-prion activity of SGI-1027 and its meta/meta analogue(M/M), previously known only as potent inhibitors of DNA methyltransferases(DNMTs). These compounds effectively decreased the level of Pr PSc in cultured cells with permanent prion infection, without affecting PrP^Cat the transcriptional or translational levels. Furthermore, SGI-1027 prevented effective prion infection of the cells. In a Pr P aggregation assay, both SGI-1027 and M/M blocked the formation of misfolded Pr P aggregates, implying that binding of these compounds hinders the Pr P conversion process. A series of binding and docking analyses demonstrated that both SGI-1027 and M/M directly interacted with the C-terminal globular domain of PrP^C, but only SGI-1027 bound to a specific region of PrP^C with high affinity, which correlates with its potent antiprion efficacy. Therefore, we report SGI-1027 and related compounds as a novel class of potential antiprion agents that preferentially function through direct interaction with PrP^C.

关键词： Prion DNMT Therapeutic compounds PrP^C Epigenetic regulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

FEA technique of hot plate forming process using cell-typed die with cooling device

引用

中国有色金属学会会刊：英文版 2012年第S3期22卷 831-837页

作者： Jung-Min LEE In-Kyu LEE Kyung-Hun LEE dae-Soon kim Byung-Min kim Dongnam Regional Division Korea Institute of Industrial Technology School of Mechanical Engineering Pusan National University Industrial Technology Division Hyundai Heavy Industries

Hot plate forming using a cell-typed die is a process for forming a large thick plate with a spherical shape for the manufacture of a large spherical LNG ***-typed upper and lower dies made of a framework of steel plates fitted to make a grid pattern are used in this process,and an air-cooling device is separately installed inside the lower die.A finite element analysis (FEA) technique was developed,which included hot forming,air flow,cooling and thermal deformation analysis for the hot plate forming process using the cell-typed ***,the convective and interface heat transfer coefficients were used to reproduce analytically the effects of the cooling device in the hot plate forming analysis.A small-scale model test of the process was conducted to verify the FEA *** analysis results show that the curvature of the final plate agrees well with that of the designed experiment within a maximum relative error of 0.03% at the corner of the plate.

关键词： cell-typed die hot plate forming spherical LNG tank heat transfer coefficient

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Flexible and transparent thin-film light-scattering photovoltaics about fabrication and optimization for bifacial operation

引用

npj Flexible Electronics 2023年第1期7卷 388-397页

作者： Soo-won Choi Jae-Ho Park Ji-Woo Seo Chaewon Mun Yonghun kim Pungkeun Song Myunghun Shin Jung-dae Kwon Surface&Nano Materials Division Korea Institute of Materials ScienceChangwonGyeongnam 51508Republic of Korea Department of Materials Science and Engineering Pusan National UniversityBusan 46241Republic of Korea Cell R&D Team Hanhwa QCells202 Sansusandan 2-roLwol-myeonJincheon-gunChungcheongbuk-do 27816Republic of Korea School of Electronics and Information Engineering Korea Aerospace UniversityGoyangGyeonggi 10540Republic of Korea Department of Advance Materials Engineering University of Science and Technology(UST)217 Gajeong-roYuseong-guDaejeon 34113Republic of Korea

Flexible and transparent thin-film silicon solar cells were fabricated and optimized for building-integrated photovoltaics and bifacial operation.A laser lift-off method was developed to avoid thermal damage during the transfer of light-scattering structures onto colorless polyimide substrates and thus enhance front-incidence photocurrent,while a dual n-type rear window layer was introduced to reduce optical losses,facilitate electron transport for rear incidence,and thus enhance performance during bifacial *** introduction of the window layer increased the rear-to-front power conversion efficiency ratio to~86%.The optimized bifacial power conversion efficiency for front and rear irradiances of 1 and 0.3 sun,respectively,equaled 6.15%,and the average transmittance within 500–800 nm equaled 36.9%.Additionally,the flexible and transparent solar cells fabricated using laser lift-off exhibited good mechanical reliability(i.e.,sustained 500 cycles at a bending radius of 6 mm)and were therefore suitable for building-integrated photovoltaics.

关键词： transparent scattering film

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comparative study of tensile and high-cycle fatigue properties of extruded AZ91 and AZ91-0.3Ca-0.2Y alloys

引用

Journal of Materials Science & Technology 2021年第34期93卷 41-52页

作者： Ye Jin kim Young Min kim Seong-Gu Hong dae Woong kim Chong Soo Lee Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Implementation Research Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Division of Industrial Metrology Korea Research Institute of Standards and ScienceDaejeon 34113Republic of Korea Energy Infra Material Measure Team Korea Research Institute of Standards and ScienceDaejeon 34113Republic of Korea Graduate Institute of Ferrous Technology Pohang University of Science and Technology.Pohang 37673Republic of Korea

Mg-Al-Zn-Ca-Y alloys with excellent ignition and corrosion resistances—termed SEN alloys(where the letters"S,""E,"and"N"stand for stainless,environmentally friendly,and non-flammable,respectively)—have been developed *** this study,the microstructure,tensile properties,and high-cycle fatigue properties of an extruded Mg-9.0Al-0.8Zn-0.1Mn-0.3Ca-0.2Y(SEN9)alloy are investigated and compared with those of a commercial Mg-9.0Al-0.8Zn-0.1Mn(AZ91)alloy extruded under the same *** the extruded SEN9 alloy and the extruded AZ91 alloy have a fully recrystallized structure comprising equiaxed grains,but the former has a smaller average grain size owing to the promoted dynamic recrystallization during *** extruded AZ91 alloy contains coarse Mg_(17)Al_(12) discontinuous precipitate(DP)bands parallel to the extrusion direction,which are formed during its cool down after *** contrast,the extruded SEN9 alloy contains relatively fine undissolved Al_(2)Ca,Al_(8)Mn_(4)Y,and Al_(2)Y second-phase particles,which are formed during the solidification stage of the casting *** tensile strength of the extruded SEN9 alloy,which has finer grains and more abundant particles,is slightly higher than that of the extruded AZ91 ***,the difference in their strengths is relatively small because the stronger solid-solution hardening and precipitation hardening effects in the extruded AZ91alloy offset the stronger grain-boundary hardening and dispersion hardening effects in the extruded SEN9alloy to some *** tensile elongation of the extruded AZ91 alloy is significantly lower than that of the extruded SEN9 alloy because the large cracks formed in the DP bands in the former cause its premature *** the extruded SEN9 alloy has higher tensile properties than the extruded AZ91alloy,the high-cycle fatigue life and fatigue strength of the former are shorter and lower,respectively,than those of the *** DP bands in the extruded

关键词： Mg-Al-Zn-Ca-Y alloy Extrusion Tensile properties High-cycle fatigue Crack source

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

60 years of Rabinowicz' criterion for adhesive wear

引用

Friction 2018年第3期6卷 341-348页

作者： Elena POPOVA Valentin L.POPOV dae-Eun kim Institute of Mechanics Technische Universit?t Berlin School of Mechanical Engineering Yonsei University Center for Nano-Wear Yonsei University

60 years ago, in 1958, Ernest Rabinowicz published a 5 page paper titled "The effect of size on the looseness of wear fragments" where he suggested a criterion determining the minimum size of wear particles. The criterion of Rabinowicz is based on the consideration of the interplay of elastic energy stored in "asperities" and the work of separation needed for detaching a wear particle. He was probably the first researcher who explicitly emphasized the role of adhesion in friction and wear. In a recent paper in Nature Communications, Aghababaei, Warner and Molinari confirmed the criterion of Rabinowicz by means of quasi-molecular dynamics and illustrated the exact mechanism of the transition from plastic smoothing to formation of wear debris. This latter paper promoted the criterion of Rabinowicz to a new paradigm for current studies of adhesive wear. The size arguments of Rabinowicz can be applied in the same form also to many other problems, such as brittle-ductile transition during indentation, cutting of materials or ultimate strength of nano-composites.

关键词： adhesion plasticity wear Archard's law of wear Rabinowicz criterion surface topography history of Tribology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development of twin wheel creep-feed grinding machine using continuous dressing for machining of aircraft rotary wing

引用

Journal of Central South University 2011年第3期18卷 704-710页

作者： kim Jin-seob HWANG Jong-dae JUNG Yoon-gyo School of Mechatronics Changwon National University

The purpose of this study is to develop a twin wheel creep-feed grinding machine using continuous dressing to machine precise axisymmetric turbine blades that have been difficult to machine using a conventional creep-feed *** order to develop such a machine,3D-modeling and machine simulations were performed and a twin wheel creep-feed grinding machine was ***,the axisymmetric precision of the machined workpieces through practical machining was evaluated and the quality of the continuous dressing effect of the developed machine was *** addition,experimental considerations for a proper dresser-to-wheel speed ratio and proper feed rate of the dresser were carried *** a result,a twin wheel creep-feed grinding machine with continuous dressing is developed through machine simulation,manufacturing and performance *** condition for the dresser feed rate is 0.3μm/*** cases of large dressor-to-wheel speed ratio,grinding efficiency can be enhanced,but the surface roughness shows a conflicting *** twin wheel creep-feed grinding machine has satisfactory appraisal with regard to surface roughness,flatness,and *** surface roughness below 0.1μm can be obtained for the blade of ***,in order to perform precise machining,it is necessary to improve the structure of the twin wheel creep-feed grinding machine.

关键词： creep-feed grinding twin wheel surface roughness grinding force continuous dressing flatness parallelism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of ozonation and coagulation on effluent organic matter characteristics and ultrafiltration membrane fouling

引用

Journal of Environmental Sciences 2014年第6期26卷 1325-1331页

作者： Kwon Jeong dae-Sung Lee Do-Gun kim Seok-Oh Ko Department of Civil Engineering Kyung Hee UniversityYongin 446-701 Korea Institute of Construction Technology KUMHO Engineering & ConstructionYongin 449-822 Korea

Effluent organic matter （EfOM） is the major cause of fouling in the low pressure membranes process for wastewater reuse. Coagulation and oxidation of biological wastewater treatment effluent have been applied for the fouling control of microfiltration membranes. However, the change in EfOM structure by pre-treatments has not been clearly identified. The changes of EfOM characteristics induced by coagulation and ozonation were investigated through size exclusion chromatography, UV/Vis spectrophotometry, fluorescence spectrophotometry and titrimetric analysis to identify the mechanisms in the reduction of ultrafiltration （UF） membrane fouling. The results indicated that reduction of flux decline by coagulation was due to modified characteristics of dissolved organic carbon （DOC） content. Total concentration of DOC was not reduced by ozonation. However, the mass fraction of the molecules with molecular weight larger than 5 kDa, fluorescence intensity, aromaticity, highly condensed chromophores, average molecular weight and soluble microbial byproducts decreased greatly after ozonation. These results indicated that EfOM was partially oxidized by ozonation to low molecular weight, highly charged compounds with abundant electron- withdrawing functional groups, which are favourable for alleviating UF membrane flux decline.

关键词： effluent organic matter fouling ultrafiltration oxidation molecular weight distribution acidity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：