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Journal of Magnesium and Alloys 2020年第2期8卷 510-522页

作者： n.pulido-Gonzalez B.Torres P.Rodrigo n.Hort J.Rams Department of Applied Mathematics Materials Science and Engineering and Electronics Technology.ESCETRey Juan Carlos UniversityC/Tulipan s/n28933 MdstolesMadridSpain Magnesium Innovation Centre Helmholtz-Zentrum Geesthacht21502 GeesthachtGermany

The as-cast Mg-3Zn-0.4Ca alloy shows a great potential to be used in biomedical applications due to its composition,mechanical properties and *** and Ca appear naturally in the organism accomplishing vital *** alloy consists of an a-Mg matrix and a eutectic composed of *** eutectic product enhances the mechanical properties of the studied alloy,causing strengthening and providing superior hardness *** this alloy,cracks initiate at the intermetallic compounds and progress through the matrix because of the open network formed by the *** to the corrosion results,the eutectic product presents a noble potential compared to the a-Mg *** this reason,the corrosion progresses preferentially through the matrix,avoiding the(α-Mg+Ca2Mg6Zri3)eutectic product,when the alloy is in direct contact to Hank's solution.

关键词： Mg-Zn-Ca alloys Biomaterials Biodegradable implants nanoindentation Three-point bending test Corrosion behaviour

Post-transplant biliary complications using liver grafts from deceased donors older than 70 years:Retrospective case-control study

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世界胃肠外科杂志:英文版(电子版) 2023年第8期15卷 1615-1628页

作者： Carlos Jimenez-Romero Iago Justo-Alonso Pilar del Pozo-Elso Alberto Marcacuzco-Quinto Cristina Martín-Arriscado-Arroba Alejandro Manrique-Municio Jorge Calvo-pulido Alvaro García-Sesma Ricardo San Román Oscar Caso-Maestro Unit of HPB Surgery and Abdominal Organs Transplantation `12 de Octubre´University HospitalMadrid 28041Spain Clinical Research Unit(I+12) `12 de Octubre´University HospitalMadrid 28041Spain Department of Radiology `12 de Octubre´University HospitalMadrid 28041Spain

BACKGROUnD The shortage of liver grafts and subsequent waitlist mortality led us to expand the donor pool using liver grafts from older *** To determine the incidence,outcomes,and risk factors for biliary complications(BC)in liver transplantation(LT)using liver grafts from donors aged>70 *** Between January 1994 and December 31,2019,297 LTs were performed using donors older than 70 *** excluding 47 LT for several reasons,we divided 250 LTs into two groups,namely post-LT BC(n=21)and without BC(n=229).This retrospective case-control study compared both *** Choledocho-choledochostomy without T-tube was the most frequent technique(76.2%in the BC group vs 92.6%in the non-BC group).Twenty-one patients(8.4%)developed BC(13 anastomotic strictures,7 biliary leakages,and 1 nonanastomotic biliary stricture).nine patients underwent percutaneous balloon dilation and nine required a Rouxen-Y hepaticojejunostomy because of dilation *** incidence of post-LT complications(graft dysfunction,rejection,renal failure,and non-BC reoperations)was similar in both *** were no significant differences in the patient and graft survival between the ***,only three deaths were attributed to *** female donors were protective factors for BC,donor cardiac arrest was a risk *** The incidence of BC was relatively low on using liver grafts>70 *** could be managed in most cases by percutaneous dilation or Roux-en-Y hepaticojejunostomy,without significant differences in the patient or graft survival between the groups.

关键词： Older liver Liver transplant Biliary complications Biliary strictures Septuagenarian donors Octogenarian donors

Bandgap engineering to tune the optical properties of Be_xMg_(1-x)X(X=S, Se, Te) alloys

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Chinese Physics B 2018年第1期27卷 415-423页

作者： B Sabir n A noor M Rashid Fasih Ud din Shahid M Ramay Asif Mahmood Centre for Advanced Studies in Physics Government College University Department of Physics School of Science University of Management and TechnologyLahore Pakistan Department of Physics COMSATS Institute of Information Technology Physics and Astronomy Department College of Science King Saud University Chemical Engineering Department College of Engineering King Saud University

Structural, electronic, and optical properties of alloys BexMgl-xX （X = S, Se, Te） in the assortment 0 〈 x 〈 1 were theoretically reported for the first time in zinc-blende （ZB） phase. The calculations were carried out by using full-potential linearized augmented plane wave plus local orbitals （FP-LAPW＋lo） formalism contained by the framework of density functional theory （DFT）. Wu--Cohen （WC） generalized gradient approximation （GGA）, based on optimization energy, has been applied to calculate these theoretical results. In addition, we used Becke and Johnson （mBJ-GGA） potential, modified form of GGA functional, to calculate electronic structural properties up to a high precision degree. The alloys were composed with the concentrations x = 0.25, 0.5, and 0.75 in pursuance of ＇special quasi-random structures＇（SQS） approach of Zunger for the restoration of disorder around the observed site of alloys in the first few shells. The structural parameters have been predicted by minimizing the total energy in correspondence of unit cell volume. Our alloys established direct band gap at different concentrations that make their importance in optically active materials. Furthermore, density of states was discussed in terms of the contribution of Be and Mg s and chalcogen （S, Se, and Te） s and p states and observed charge density helped us to investigate the bonding nature. By taking into consideration of immense importance in optoelectronics of these materials, the complex dielectric function was calculated for incident photon energy in the range 0--15 eV.

关键词： BexMgl-xX (X = S Se Te) alloys zinc-blende (ZB) phase density functional theory (DFT),electronic and optical properties

Intertwined leukocyte balances in tumours and peripheral blood as robust predictors of right and left colorectal cancer survival

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World Journal of Gastrointestinal Oncology 2022年第1期14卷 295-318页

作者： Ramón Cantero-Cid Karla Marina Montalbán-Hernández Jenny Guevara Alejandro Pascual-Iglesias Elisa pulido JoséCarlos Casalvilla Cristóbal Marcano Cristina Barragán Serrano Jaime Valentín Gloria Cristina Bonel-Pérez JoséAvendaño-Ortiz Verónica Terrón Roberto Lozano-Rodríguez Alejandro Martín-Quirós Elvira Marín Eva Pena Laura Guerra-Pastrián Eduardo López-Collazo Luis Augusto Aguirre Tumor Immunology Laboratory The Innate Immune Response GroupHospital La Paz Institute for Health Research(IdiPAZ)Madrid 28046Spain Digestive Surgery Service La Paz University HospitalMadrid 28046Spain Emergency Department and Emergent Pathology Research Group Hospital La Paz Institute for Health Research(IdiPAZ)Madrid 28046Spain Pathologic Anatomy Service Hospital La PazMadrid 28046Spain

BACKGROUnD Colorectal cancer(CRC)accounts for 9.4%of overall cancer deaths,ranking second after lung *** the large number of factors tested to predict their outcome,most patients with similar variables show big differences in ***,right-sided CRC(RCRC)and left-sided CRC(LCRC)patients exhibit large differences in outcome after surgical intervention as assessed by preoperative blood leukocyte *** hypothesised that stronger indexes than circulating(blood)leukocyte ratios to predict RCRC and LCRC patient outcomes will result from combining both circulating and infiltrated(tumour/peritumour fixed tissues)concentrations of *** To seek variables involving leukocyte balances in peripheral blood and tumour tissues and to predict the outcome of CRC *** Sixty-five patients diagnosed with colon adenocarcinoma by the Digestive Surgery Service of the La Paz University Hospital(Madrid,Spain)were enrolled in this study:43 with RCRC and 22 with *** were followed-up from January 2017 to March 2021 to record overall survival(OS)and recurrence-free survival(RFS)after surgical *** concentrations in peripheral blood were determined by routine laboratory ***-fixed samples of tumour and peritumoural tissues were assessed for leukocyte concentrations by immunohistochemical detection of CD4,CD8,and CD14 marker *** of leukocyte concentration in blood and tissues were calculated and evaluated for their predictor values for OS and RFS with Spearman correlations and Cox univariate and multivariate proportional hazards regression,followed by the calculation of the receiver-operating characteristic and area under the curve(AUC)and the determination of Youden’s optimal cutoff values for those variables that significantly correlated with either RCRC or LCRC patient *** patients from the cohort were randomly assigned to modelling and validation sets,and clinician-friendly nomogra

关键词： Left colorectal cancer Leukocyte ratios Prognostic variables Recurrence-free survival Right colorectal cancer Overall survival

Role of hypoxia preconditioning in therapeutic potential of mesenchymal stem-cell-derived extracellular vesicles

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World Journal of Stem Cells 2022年第7期14卷 453-472页

作者： Victoria pulido-Escribano Bárbara Torrecillas-Baena Marta Camacho-Cardenosa Gabriel Dorado MaríaÁngeles Gálvez-Moreno Antonio Casado-Díaz Unidad de Gestión Clínica de Endocrinología y nutrición-GC17 Instituto Maimónides de Investigación Biomédica de CórdobaHospital Universitario Reina SofíaCórdoba 14004Spain Dep.Bioquímica y Biología Molecular Campus Rabanales C6-1-E17Campus de Excelencia Internacional Agroalimentario(ceiA3)Universidad de CórdobaCIBERFESCórdoba 14071Spain

The use of mesenchymal stem-cells(MSC)in cell therapy has received considerable attention because of their *** properties include high expansion and differentiation in vitro,low immunogenicity,and modulation of biological processes,such as inflammation,angiogenesis and ***,the regenerative effect of MSC is partly due to their paracrine *** has prompted numerous studies,to investigate the therapeutic potential of their secretome in general,and specifically their extracellular vesicles(EV).The latter contain proteins,lipids,nucleic acids,and other metabolites,which can cause physiological changes when released into recipient ***,contents of EV can be modulated by preconditioning MSC under different culture *** them,exposure to hypoxia stands out;these cells respond by activating hypoxia-inducible factor(HIF)at low O_(2) *** has direct and indirect pleiotropic effects,modulating expression of hundreds of genes involved in processes such as inflammation,migration,proliferation,differentiation,angiogenesis,metabolism,and cell *** of these genes is reflected in the contents of secreted ***,numerous studies show that MSC-derived EV conditioned under hypoxia have a higher regenerative capacity than those obtained under *** this review,we show the implications of hypoxia responses in relation to tissue *** addition,hypoxia preconditioning of MSC is being evaluated as a very attractive strategy for isolation of EV,with a high potential for clinical use in regenerative medicine that can be applied to different pathologies.

关键词： Cell priming Extracellular vesicles Hypoxia Hypoxia-inducible factor Mesenchymal stemcells Regenerative medicine

Synthesis of crystalline perovskite-structured SrTiO_3 nanoparticles using an alkali hydrothermal process

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International Journal of Minerals,Metallurgy and Materials 2016年第1期23卷 109-115页

作者： U.K.n.din.T.H.T.Aziz M.M.Salleh A.A.Umar Institute of Microengineering and nanoelectronics (IMEn) Universiti Kebangsaan Malaysia

We report an experimental route for synthesizing perovskite-structured strontium titanate （SrTiO3） nanocubes using an alkali hydrothermal process at low temperatures without further heating. Furthermore, we studied the influence of heating time （at 180℃） on the crystallinity, morphology, and perovskite phase formation of SrTiO3. The SrTiO3 powder, which is formed via nanocube agglomeration, transforms into cubic particles with a particle size of 120--150 nm after 6 h of hydrothermal sintering. The crystallinity and percentage of the perovskite phase in the product increased with heating time. The cubic particles contained 31.24at% anatase TiO2 that originated fi＇om the precursor. By varying the weight ratio of anatase TiO2 used to react with the strontium salt precursor, we reduced the anatase-TiO2 content to 18.8at%. However, the average particle size increased when the anatase-TiO2 content decreased.

关键词： strontium titanate nanoparticles anatase hydrothermal synthesis

基体表面粗糙度对非晶碳薄膜摩擦磨损性能的影响

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材料保护 2024年第6期57卷 68-73,80页

作者：李一治刘京周丁子珊江小辉郭维诚鞠鹏飞上海理工大学机械工程学院上海200093 上海航天设备制造总厂有限公司上海200245

为了探究不同基体表面粗糙度对非晶碳薄膜摩擦磨损性能的影响,改善2Cr13试样表面在601EF润滑脂润滑下的摩擦学性能,使用机加工、抛光等方式在2Cr13试样表面制备不同的表面粗糙度,然后采用磁控溅射法在不同粗糙度样件表面制备非晶碳薄膜... 详细信息

为了探究不同基体表面粗糙度对非晶碳薄膜摩擦磨损性能的影响,改善2Cr13试样表面在601EF润滑脂润滑下的摩擦学性能,使用机加工、抛光等方式在2Cr13试样表面制备不同的表面粗糙度,然后采用磁控溅射法在不同粗糙度样件表面制备非晶碳薄膜,采用球-盘接触的摩擦磨损试验研究了在601EF润滑脂润滑条件下非晶碳薄膜及氮化硅球的摩擦磨损性能,通过光学显微镜对磨损处进行分析。结果表明:与基体表面对摩的Si_(3)n_(4)球均磨出了明显的平台,而基体表面并未出现明显的磨痕,Ra范围在0.20~0.75μm样品对偶球的磨损量要小,磨斑面积范围为0.152~0.165 mm^(2),磨损形式为黏着磨损,Ra范围在0.95~3.19μm样品对偶球的磨损量要大,磨斑面积范围为0.228~0.275 mm^(2),出现了犁沟状磨痕,磨损较为严重;在相同的工况条件下,随着基体表面粗糙度的增大,两摩擦副间的启动、平均摩擦系数以及Si_3n_4球的磨损量均呈先减小后增大再减小的趋势,当Ra为0.56μm时,非晶碳薄膜的摩擦学性能最好,摩擦系数曲线较为稳定,平均摩擦系数为0.162,其对偶球磨损量最小,为0.152 mm^(2)。基体表面粗糙度影响非晶碳薄膜的摩擦学性能,通过机加工、抛光等手段在基体表面制备合适的粗糙度可以得到具有良好减摩性能的表面。

关键词：基体表面粗糙度非晶碳薄膜摩擦磨损 601EF润滑脂 Si_3n_4球

Design and Analysis of Graphene Based Tunnel Field Effect Transistor with Various Ambipolar Reducing Techniques

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Computers, Materials & Continua 2023年第7期76卷 1309-1320页

作者： Puneet Kumar Mishra Amrita Rai nitin Sharma Kanika Sharma nitin Mittal Mohd Anul Haq Ilyas Khan ElSayed M.Tag El din Department of Electronics and Communication Engineering G L Bajaj Institute of Technology and ManegmentGretear NoidaIndia Department of Electronics and Communication Engineering Chandigarh UnievrsityMohaliPunjabIndia Department of Electronics and Communication Engineering NITTTRChandigarhIndia University Center of Research&Development Chandigarh UniversityMohali121102India Department of Computer Science College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of Mathematics College of Science Al-ZulfiMajmaah University11952Al-MajmaahSaudi Arabia Electrical Engineering Department Faculty of Engineering&TechnologyFuture University in EgyptNew Cairo11835Egypt

The fundamental advantages of carbon-based graphene material,such as its high tunnelling probability,symmetric band structure(linear dependence of the energy band on the wave direction),low effective mass,and characteristics of its 2D atomic layers,are the main focus of this research *** impact of channel thickness,gate under-lap,asymmetric source/drain doping method,workfunction of gate contact,and High-K material on Graphene-based Tunnel Field Effect Transistor(TFET)is analyzed with 20 nm *** modelling and electrical characteristic performance have been simulated using the Atlas device simulator of SILVACO TCAD with user-defined material syntax for the newly included graphene material in comparison to silicon carbide(SiC).The simulation results in significant suppression of ambipolar current to voltage characteristics of TFET and modelled device exhibits a significant improvement in subthreshold swing(0.0159 V/decade),the ratio of Ion/Ioff(1000),and threshold voltage(-0.2 V with highly doped p-type source and 0.2 V with highly doped n-type drain)with power supply of 0.5 V,which make it useful for low power digital applications.

关键词： Graphene tunnel field effect transistor(TFET) band to band tunnelling subthreshold swing

High-Bandwidth,Low-Power CMOS Transistor Based CAB for Field Programmable Analog Array

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Computers, Materials & Continua 2023年第3期74卷 5885-5900页

作者： Ameen Bin Obadi Alaa El-din Hussein Samir Salem Al-Bawri Kabir Hossain Abdullah Abdulhameed Muzammil Jusoh Thennarasan Sabapathy Ahmed Jamal Abdullah Al-Gburi Mahmoud A.Albreem Advanced Communication Engineering(ACE) Centre of ExcellenceUniversiti Malaysia Perlis(UniMAP)Faculty of Electronic Engineering TechnologyKangar01000Malaysia Electrical Engineering King Fahd University of Petroleum and MineralsDhahranEastern31261Saudi Arabia Space Science Centre Climate Change InstituteUniversiti Kebangsaan MalaysiaBangi43600Malaysia Department of Electronics&Communication Engineering Faculty of Engineering&PetroleumHadhramout UniversityAl-MukallaHadhramout50512Yemen Faculty of Engineering Norwegian University of Science and Technology(NTNU)GjovikN-2815Norway Faculty of Electronic Engineering Technology Universiti Malaysia Perlis(UniMAP)Kampus Alam UniMAP Pauh PutraArau02600Malaysia Department of General Educational Development Faculty of Science and Information Technology(FSIT)Daffodil International UniversityDhaka1207Bangladesh Department of Electronics and Computer Engineering(FKEKK) Center for Telecommunication Research and Innovation(CeTRI)Universiti Teknikal Malaysia Melaka(UTeM)Durian Tungal76100Malaysia Department of Electrical Engineering University of SharjahSharjah27272United Arab Emirates

This article presents an integrated current mode configurable analog block(CAB)system for field-programmable analog array(FPAA).The proposed architecture is based on the complementary metal-oxide semiconductor(CMOS)transistor level design where MOSFET transistors operating in the saturation region are *** proposed CAB architecture is designed to implement six of thewidely used current mode operations in analog processing systems:addition,subtraction,integration,multiplication,division,and pass *** functionality of the proposed CAB is demonstrated through these six operations,where each operation is chosen based on the user’s selection in the CAB interface *** architecture of the CAB system proposes an optimized way of designing and integrating only three functional cells with the interface circuitry to achieve the six ***,optimized programming and digital tuning circuitry are implemented in the architecture to control and interface with the functional ***,these designed programming and tuning circuitries play an essential role in optimizing the performance of the proposed *** of the proposed CMOS Transistor Based CAB system is carried out using Tanner EDA Tools in 0.35μm standard CMOS *** design uses a±1.5 V power supply and results in maximum 3 dB bandwidth of 34.9 MHz and an approximate size of 0.0537 *** demonstrates the advantages of the design over the current state-of-the-art designs presented for comparison in this ***,the proposed design has a clear aspect of simplicity,low power consumption,and high bandwidth operation,which makes it a suitable candidate for mobile telecommunications applications.

关键词： CMOS field programmable analog array configurable analog block current mode circuit

Intravitreal dexamethasone implant in naive and previously treated patients with diabetic macular edema:a retrospective study

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International Journal of Ophthalmology(English edition) 2020年第10期13卷 1597-1605页

作者： Marta Medina-Baena Olga Cejudo-Corbalán Juan Ignacio García-pulido María Jesús Huertos-Carrillo Eloy Girela-López Hospital Universitario Puerto Real Puerto Real 11510CadizSpain University of Cordoba Cordoba 14004Spain

AIM:To assess the effect of the intravitreal dexamethasone implant(DEX)Ozurdex on the best corrected visual acuity(BCVA)and central retinal thickness(CRT)in patients with diabetic macular edema(DME).METHODS:Totally 43 eyes(24 naive and 19 previously treated)were included in the *** and single-center study involved patients with a clinical diagnosed of DME,who received treatment with DEX implant and had a follow-up of at least 12 *** endpoints included changes in BCVA and ***:At month 12,mean improvement in BCVA from baseline was 20.4±20.8 letters and 6.8±6.9 letters in naive and previously treated patients,respectively(P=0.0132).The naive patients achieved the BCVA improvement significantly faster(2.4±1.5 mo)than the previously treated ones(3.5±2.4 mo,P=0.0298;MannWhitney test).The proportion of eyes gaining≥15 letters was 54.2%and 21.1%in the non-previously treated and previously treated groups,respectively(P=0.0293).CRT was significantly reduced from 484.0±119.8 and 487.5±159.9μm to 272.0±39.2 and 233.5±65.7μm in the naive and previously treated patients,respectively;Pnce of subretinal fluid was significantly associated with the proportion of patients achieving a BCVA improvement≥5 letters[HR(95%CI),1.23(1.04 to 1.45),P=0.0145];≥10 letters[HR(95%CI),1.75(1.10 to 2.77),P=0.0182];and≥15 letters[HR(95%CI),2.04(1.03 to 4.02),P=0.0407].naive patients received less DEX implants throughout the study than the previously treated ones(1.8±0.6 vs 2.3±0.6,P=0.0172,respectively).Totally 9 patients(20.9%)have developed ocular hypertension,which was successfully controlled with topical hypotensive *** the 23 phakic eyes at baseline,5 eyes(21.7%)either had new onset lens opacity or progression of an existing opacity during the study *** of them(2 in the naive group and 2 in the previously treated one)required cataract surgery at months 4,6,6,and 6,***:The results obtained in this

关键词： diabetic macular edema dexamethasone implant Ozurdex visual acuity central retinal thickness naive patients