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Nano Research 2013年第7期6卷 511-524页

作者： Christopher C. m. Neumann eduardo Laborda Kristina Tschulik Kristopher R. Ward Richard G. Compton Department of Chemistry Physical and Theoretical Chemistry Laboratory Oxford University South Parks Road Oxford OXl 3QZUnited Kingdom

The electrocatalytic activity for oxygen reduction reaction （ORR） at neutral pH of citrate-capped silver nanoparticles （diameter = 18 nm） supported on glassy carbon （GC） is investigated voltammetrically. Novelly, the modification of the substrate by nanoparticles sticking to form a random nanoparticle array and the voltammetric experiments are carried out simultaneously by immersion of the GC electrode in an air-saturated 0.1 m NaC104 solution （pH = 5.8） containing chemically-synthesized nanoparticles. The experimental voltammograms of the resulting nanoparticle array are simulated with homemade programs according to the two-proton, two-electron reduction of oxygen to hydrogen peroxide where the first electron transfer is rate determining. In the case of silver electrodes, the hydrogen peroxide generated is partially further reduced to water via heterogeneous decomposition. Comparison of the results obtained on a silver macroelectrode and silver nanoparticles indicates that, for the silver nanoparticles and particle coverages （0.035%-0.457%） employed in this study, the ORR electrode kinetics is slower and the production of hydrogen peroxide larger on the glassy carbon-supported nanoparticles than on bulk silver.

关键词： oxygen reduction reaction silver nanoparticles nanoelectrocatalysis hydrogen peroxide escape fuel cells

Efficiency of soil-applied ^(67)Zn-enriched fertiliser across three consecutive crops

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Pedosphere 2021年第4期31卷 531-537页

作者： Edson m.mATTIELLO eduardo L.CANCELLIER Rodrigo C.DA SILVA Fien DEGRYSE Roslyn BAIRD mike J.mCLAUGHLIN Department of Soil Science Universidade Federal de ViçosaViçosaMinas Gerais(Brazil) Department of Soil Science Universidade Federal de LavrasMinas Gerais(Brazil) The University of Adelaide School of AgricultureFood and WineFertiliser Technology Research CentrePMB 1Waite CampusGlen Osmond SA 5064(Australia)

A very small amount of applied zinc(Zn) is taken up by crops, resulting in low recovery by plants. Adding elemental sulphur to zinc oxide(ZnO) fertiliser could improve Zn solubilisation and exert a higher residual effect on crops than soluble Zn sources. We produced an isotopically labelled Zn-elemental sulphur fertiliser and evaluated its performance in comparison to traditional Zn sources during sequential crop cultivation. Three ^(67)Zn-labelled fertilisers,ZnO, zinc sulphate(ZnSO_(4)), and ZnO co-granulated with elemental sulphur(ZnOS^(0)), were soil applied, and their contributions to the uptake of Zn by three consecutive crops, wheat, ryegrass, and corn, were assessed in a 294-d pot experiment. The contributions of Zn fertilisers followed the order: ZnSO_(4) > ZnO= ZnOS^(0). The relative contributions of Zn fertilisers were lower in the first crop than in the subsequent crops. The overall recovery of applied Zn by the three crops was higher for ZnSO_(4) than for ZnO and ZnOS^(0), reaching 1.56%, 0.45%, and 0.33% of the applied Zn, respectively. Zinc recovery by plants was very low, regardless of the source of Zn. Adding elemental sulphur to ZnO did not increase its effectiveness up to 294 d after application. Fertiliser contribution was higher for the subsequent crops than for the initial crop, indicating the importance of assessing the residual effects of Zn fertilisers.

关键词： agronomic biofortification elemental sulphur fertilizer residual effect plant uptake Zn bioavailability Zn fertilization Zn source

Dendritic Growth, Eutectic Features and Their Effects on Hardness of a Ternary Sn–Zn–Cu Solder Alloy

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Acta metallurgica Sinica(English Letters) 2017年第6期30卷 528-540页

作者： Bismarck Luiz Silva Rodrigo Valenzuela Reyes Amauri Garcia Joséeduardo Spinelli Department of materials Engineering Federal University of Rio Grande do Norte-UFRNNatalRN 59078-970Brazil Department of materials Engineering Federal University of Sao Carlos-UFSCarSao CarlosSP 13565-905Brazil Department of manufacturing and materials Engineering University of CampinasUNICAMPCampinasSP 13083-860Brazil

The present investigation is based on the results of a directionally solidified （DS） Sn-9 wt%Zn-2 wt%Cu alloy, including primary/secondary/tertiary dendrite arm spacings of the Sn-rich matrix, the morphologies of the eutectic mixture and the corresponding interphase spacing, the nature and proportion of the Cu-Zn intermetallic compound （ImC）. The main purpose is to establish interrelations of these microstructure features with experimental solidification thermal parameters, such as cooling rates and growth rates （v）, macrosegregation and hardness. Such interrelations are interesting for both industry and academy since they represent a tool permitting the preprogramming of final properties based on the design of the microstructure. In the case of Sn-Zn-Cu alloys, hardly anything is known about the combined effects of the length scale of the microstructure and fraction and distribution of the primary ImC on hardness. The alloy microstructure is composed of a β-Sn dendritic region, surrounded by a eutectic mixture of α-Zn and β-Sn phases and the γ-Cu5Zn8 ImC. The eutectic interphase spacing varies in the range 1.2-3.6 μm, with the α-Zn phase having a globular morphology for ν 〉 0.5 mm/s and a needle-like morphology for ν 〈 0.3 mm/s. A modified Hall-Petch-type experimental expression relating hardness to the interphase spacing is proposed.

关键词： Sn-Zn-Cu solder alloy Solidification microstructure Eutectic morphology Hardness

Design of a Novel Exoskeleton with Passive magnetic Spring Self-locking and Spine Lateral Balancing

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Journal of Bionic Engineering 2024年第1期21卷 236-255页

作者： Jhon F.Rodríguez-León Betsy D.m.Chaparro-Rico Daniele Cafolla Francesco Lago eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico Department of mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly Faculty of Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTER University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical *** proposed design is based on a novel PRRRP(P-Prismatic;R-Revolute)kinematic chain with 5 passive Degrees of Freedom(DoF).Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task *** proposed exoskeleton incorporates a balancing mechanism to alleviate discomfort and spinal torsional effects also helping in limb weight *** paper reports specific models and simulations to demonstrate the feasibility and effectiveness of the proposed *** experimental characterization is performed to validate the performance of the mechanism in terms of forces and physical strain during a specific application consisting of ceiling-surface drilling *** obtained results preliminarily validate the engineering feasibility and effectiveness of the proposed exoskeleton in the intended operation task thereby requiring the user to exert significantly less force than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Is autoimmune hepatitis a frequent finding among HCV patients with intense interface hepatitis?

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World Journal of Gastroenterology 2010年第29期16卷 3704-3708页

作者： Rosilene G Badiani Vitória Becker Renata m Perez Carla AL matos Lara B Lemos Valéria P Lanzoni Luis eduardo C Andrade Alessandra Dellavance Antonio eduardo B Silva maria Lucia G Ferraz Division of Gastroenterology Federal University of Sao Paulo04023-900Sao PauloBrazil Department of Internal medicine Federal University of Rio de Janeiro21941-913Rio de JaneiroBrazil Department of Pathology Immunology Group Fleury medicine and Health 不详

AIm:To evaluate the overlap of autoimmune hepatitis in hepatitis C virus(HCV)-infected patients with intense interface ***:Among 1759 patients with hepatitis C submitted to liver biopsy,92(5.2%) presented intense interface *** patients were evaluated regarding the presence of antinuclear antibody(ANA),anti-smooth muscle antibody(SmA) and anti-liver/kidney microsomal antibody(LKm-1),levels of γ-globulin and histological findings related to autoimmune hepatitis(plasma cell infiltrate and presence of rosettes).RESULTS:Among patients with hepatitis C and intense interface hepatitis there was a low prevalence of autoantibodies(ANA=12%,SmA=5%,LKm-1=0%) and the median γ-globulin level was within the normal *** histological findings of autoimmune disease were observed in only two cases(2%).After applying the score for diagnosis of autoimmune hepatitis,only one patient was classified with a definitive diagnosis of autoimmune *** overlap with autoimmune hepatitis was not the explanation for the intense necroinflammatory activity in patients with chronic hepatitis C we sought to identify the variables associated with this *** presence of intense interface hepatitis was associated with more advanced age,both at the time of infection and at the time of the biopsy,and higher prevalence of blood transfusion and alcohol ***:Although possible,overlap with autoimmune hepatitis is a very rare association in HCV-infected patients with intense interface hepatitis,an unusual presentation which seems to be related to other host variables.

关键词： Hepatitis C Liver biopsy Antinuclear antibody Autoimmune hepatitis Interface hepatitis

Hydrothermal alteration of the surface volcanic rocks at the Acoculco geothermal field,mexico:a multi-parametric approach

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Acta Geochimica 2024年第6期43卷 1037-1053页

作者： America Yosiris García-Soto Kailasa Pandarinath ESantoyo eduardo Gonzalez-Partida Instituto de Energías Renovables Universidad Nacional Autónoma de MéxicoPriv.Xochicalco s/no.Col.CentroApartado Postal 3462580 TemixcoMorelosMexico Centro de Geociencias UNAMApartado Postal 1-74276001 QuerétaroQuerétaroMexico

The studies on hydrothermal alteration-induced eff ects in surface and subsurface rocks provide useful information in the characterization and exploitation of a geothermal ***,these studies are based on traditional,and reliable methods like petrography(primary and secondary minerals,and grade of alteration),and geochemistry(mobility of elements,changes in mass and concentration of elements,and fluid inclusions).Recently,apart from these established methods,some methods based on the geochemical(Chemical Index of Alteration,CIA;Weathering Index of Parkar,WIP;Loss on Ignition,LOI;and Sulfur,S)and rock magnetic properties(magnetic susceptibility,χlf;and percentage frequency-dependent susceptibility,χfd%)are also being applied in the identification of whether a rock is an altered or a fresh *** Acoculco Geothermal Field(AGF),mexico,is characterized by high temperature and very low permeability,and it is considered a promissory Enhanced Geothermal *** following changes are observed in the rocks as a result of an increase in hydrothermal alteration:(1)an increase in CIA,LOI,and S values,and a decrease in WIP;(2)an increase in quartz and quartz polymorph minerals(silicification),and clay minerals(argillization);and(3)decrease inχlf *** AGF,the most altered surface acid rocks are characterized by entirely quartz and its polymorphs,and clay *** present study also indicates the applicability of the binary plots of major elements(felsic vs mafic component)and rock magnetic parameters(χlf vs.χfd%).The rock withχfd%value of 2-10 andχlf valuem^(3) kg^(-1)indicate the presence of single domain and stable single domain grains,which in turn suggests that it is an altered *** methods are simple to apply,rapid,reliable,and have the potential to become eff ective tools for the identifi cation of hydrothermally altered rocks during the initial stage of geothermal exploration.

关键词： Geothermal fields Hydrothermal alteration Surface rocks magnetic susceptibility Alteration indices

Hyperelastic membrane Actuators:Analysis of Toroidal and Helical multifunctional Configurations

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Cyborg and Bionic Systems 2022年第1期2022卷 129-140页

作者： eduardo Perez-Guagnelli Joanna Jones Dana D.Damian Department of Automatic Control and Systems Engineering Universty of Shefield UK

Technologies that providemechanical assistance arerequired inthemdicalfeld,such asimplants that regenerate tssuethroughelongation and *** ofthe challenges is to develop actuators that combinethe benefits ofhigh axialextension at lowpressures,modularity,multifunction,and load bearing capabilities into one design while maintaining their shape and *** such a challenge wll provide implants with enhanced capacity for mechanical assistance to induce *** introduce two novel actuators(m2H)built of stacked Hyperelastic Balloning membrane Actuators(HBmAs)that can be realized using helical and toroidal *** restraining the HBmA expansion deterministicallyusing a semisoft exoskeleton,the actuatorsors areendoweded withh axial extension and radial expansion *** actuatorsare thus built of modules that canconfiguured different therapeutical needs and multifunctionality,to provideanatomically congruent *** desigl,fabricationtestin;and numerical and experimental validation ofthe *** can aaxiallyind6 in their helicaland toroidal configurations at input pressuresas low as 26 and 24 kPa,*** the axial module is used separately,its extension capacity reaches>170%.The m2H-HBmAs can perform independent and simultaneousxpansion and extension motions with negligible intraluminaldeformation as well as stand at least 1kg of axial force without *** m2H-HBmAs overcome the limitations ofhyperexpanding machines that show low resistance to *** envisage m2H-HBmAs as promising tools to perform tisueregeneration procedures.

关键词： restrain overcome skeleton

Chemotherapy for gastric cancer

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World Journal of Gastroenterology 2006年第2期12卷 204-213页

作者： Javier Sastre Jose Angel García-Saenz eduardo Díaz-Rubio Servicio de Oncologia médica HCU San Carlosc/Martín Lagos s/n 28040 MadridSpain Servicio de Oncologia médica HCU San Carlosc/Martía Lagos s/n 28040 MadridSpain

metastatic gastric cancer remains a non-curative disease. Palliative chemotherapy has been demonstrated to prolong survival without quality of life compromise. many single-agents and combinations have been confirmed to be active in the treatment of metastatic disease. Objective response rates ranged from 10-30% for single-agent therapy and 30-60% for polychemotherapy. Results of phase Ⅱ and Ⅲ studies are reviewed in this paper as well as the potential efficacy of new drugs. For patients with localized disease, the role of adjuvant and neoadjuvant chemotherapy and radiation therapy is discussed. most studies on adjuvant chemotherapy failed to demonstrate a survival advantage, and therefore, it is not considerecl as standard treatment in most centres. Adjuvant immunochemotherapy has been developed fundamentally in Korea and Japan. A meta-analysis of phase Ⅲ trials with OK-432 suggested that immunochemotherapy may improve survival of patients with curatively resected gastric cancer. Based on the results of US Intergroup 0116 study, postoperative chemoradiation has been accepted as standard care in patients with resected gastric cancer in North America. However, the results are somewhat confounded by the fact that patients underwent less than a recommended D1 lymph node dissection and the pattern of recurrence suggested a positive effect derived from local radiotherapy without any effect on micrometastatic disease. Neoadjuvant chemotherapy or chemoradiation therapy remains experimental, but several phase Ⅱ studies are showing promising results. Phase Ⅲ trials are needed.

关键词： Gastric cancer Chemotherapy Adjuvant treatment

Angiotensin Ⅱ receptor blockers and gastrointestinal adverse events of resembling sprue-like enteropathy:a systematic review

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Gastroenterology Report 2019年第3期7卷 162-167,I0001页

作者： Ayesha Kamal Christopher Fain Angela Park Peiqi Wang eduardo Gonzalez-Velez Daniel A.Leffler Susan m.Hutfless Department of medicine Division of GastroenterologyJohns Hopkins UniversityBaltimoreMDUSA Johns Hopkins Department of Surgery and Surgical SciencesJohns Hopkins UniversityBaltimoreMDUSA Division of Gastroenterology Beth Israel Deaconess Medical CenterBostonMAUSA Department of Epidemiology Johns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA

Background:Olmesartan,an angiotensin Ⅱ receptor blocker(ARB),is associated with gastrointestinal symptoms resembling sprue-like *** have proposed that enteropathy may be a class effect rather than *** performed a systematic review to identify literature of sprue-like enteropathy for all ***:Case reports,case series and comparative studies of ARBs were searched on Pubmed and Embase databases through 21 November 2018 and then ***:A total of 82 case reports and case series as well as 5 comparative studies,including 248 cases,were selected and *** ARBs listed in the case reports were olmesartan(233 users;94.0%),telmisartan(5 users;2.0%),irbesartan(4 users;1.6%),valsartan(3 users;1.2%),losartan(2 users;0.8%)and eprosartan(1 user;0.4%).The periods between ARB initiation and onset of symptoms ranged from 2 weeks to 13 *** results were reported in 218 cases,in which 201 cases(92.2%)were villous atrophy and 131 cases(60.1%)were intraepithelial *** leucocyte antigen(HLA)testing was performed in 147 patients,among whom 105(71.4%)had HLA-DQ2 or HLA-DQ8 *** antibodies were tested in 169 patients,among whom 167(98.8%)showed negative *** exclusion from the diet failed to relieve symptoms of enteropathy in 127(97.7%)of 130 patients with *** remission of symptoms after discontinuation of ARB was reported in 233(97.4%)of the 239 patients with *** cases(2.8%)reported recurrence of symptoms after restarting olmesartan;rechallenge was not reported for the non-olmesartan *** retrospective studies conducted worldwide had inconsistent study designs(*** in periods of study and case definition)and ***:Although enteropathy is rare,clinicians should remain vigilant of this potential adverse event even years after medication initiation.

关键词： angiotensinⅡreceptor blockers olmesartan enteropathy diarrhea

Identific tion of quantitative trait loci and associated candidate genes for pregnancy success in Angus–Brahman crossbred heifers

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Journal of Animal Science and Biotechnology 2024年第1期15卷 162-170页

作者： Quinn A.Hoorn Gabriel A.Zayas eduardo E.Rodriguez Laura m.Jensen Raluca G.mateescu Peter J.Hansen Department of Animal Sciences Donald Henry Barron Reproductive and Perinatal Biology Research Programand the Genetics InstituteUniversity of FloridaGainesvilleFLUSA School of Applied Systems Biology La Trobe UniversityBundooraVIC 3083Australia

Background In beef cattle, more than 50% of the energy input to produce a unit of beef is consumed by the female that produced the calf. Development of genomic tools to identify females with high genetic merit for reproductive function could increase the profitability and sustainability of beef *** Genome-wide association studies(GWAS) were performed using a single-step genomic best linear unbiased prediction approach on pregnancy outcome traits from a population of Angus–Brahman crossbred heifers. Furthermore, a validation GWAS was performed using data from another farm. Heifers were genotyped with the Bovine GGP F250 array that contains 221,077 SNPs. In the discovery population, heifers were bred in winter breeding seasons involving a single round of timed artificial insemination(AI) followed by natural mating for 3 months. Two phenotypes were analyzed: pregnancy outcome to first-service AI(PAI;n = 1,481) and pregnancy status at the end of the breeding season(PEBS;n = 1,725). The heritability was estimated as 0.149 and 0.122 for PAI and PEBS, respectively. In the PAI model, one quantitative trait locus(QTL), located between 52.3 and 52.5 mb on BTA7, explained about 3% of the genetic variation, in a region containing a cluster of γ-protocadherin genes and SLC25A2. Other QTLs explaining between 0.5% and 1% of the genetic variation were found on BTA12 and 25. In the PEBS model, a large QTL on BTA7 was synonymous with the QTL for PAI, with minor QTLs located on BTA5, 9, 10, 11, 19, and 20. The validation population for pregnancy status at the end of the breeding season were Angus–Brahman crossbred heifers bred by natural mating. In concordance with the discovery population, the large QTL on BTA7 and QTLs on BTA10 and 12 were *** In summary, QTLs and candidate SNPs identified were associated with pregnancy outcomes in beef heifers, including a large QTL associated with a group of protocadherin genes. Confirmation of these associations

关键词： Beef cattle Fertility GWAS QTL