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First serological Evidence on Endemicity of HEV Infection in Wild Boar(sus scrofa) Populations from Portugal

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Virologica sinica 2018年第2期33卷 197-200页

作者： Daniel Goncalves joao pereira-Vaz Vitor Duque Victor Bandeira Carlos Fonseca Ana Donato Cristina Luxo Ana Miguel Matos Laboratory of Virology Faculty of Pharmacy University of Coimbra 3000-548 Coimbra Portugal Laboratory of Molecular Biology Clinical Pathology UnitHospital and University Centre of Coimbra3000-602 Coimbra Portugal Infectious Diseases Department Hospital and University Centre of Coimbra 3000-075 Coimbra Portugal Biology Department and CEsAM University of Aveiro3810-193 Aveiro Portugal Clinical Laboratory Faculty of Pharmacy University of Coimbra 3000-548 Coimbra Portugal Research Centre on Chemical Processes Engineering and Forest Products (CIEPQF) Faculty of Pharmacy University of Coimbra 3030-790 Coimbra Portugal

Increasing number of hepatitis E virus（HEV）infection has been described in industrialized countries,with infection occurring as a sporadic disease,usually associated with travel to endemic regions or small outbreaks... 详细信息

关键词：感染 HEV 血清学葡萄牙野猪证据特性人口

Frequency Response Optimization of Dual Depletion InGaAs/InP PIN Photodiodes

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Photonic sensors 2016年第1期6卷 63-70页

作者： J. M. Torres.pereira joao Paulo N. TORREs Instituto de Telecomunicacoes Instituto Superior Tecnico-Universidade de Lisboa Lisboa Portugal

The frequency response of a dual depletion p-i-n （PIN） photodiode structure is investigated. It is assumed that the light is incident on the N side and the drift region is located between the N contact and the absorption region. The numerical model takes into account the transit time and the capacitive effects and is applied to photodiodes with non-uniform illumination and linear electric field profile. With an adequate choice of the device＇s structural parameters, dual depletion photodiodes can have larger bandwidths than the conventional PIN devices.

关键词： PIN photodiodes dual depletion frequency response modeling

Transesterification of sunflower oil in microchannels with circular obstructions

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Chinese Journal of Chemical Engineering 2018年第4期26卷 852-863页

作者： Harrson s.santana joao L.silva Jr Deborah s.Tortola Osvaldir P.Taranto school of Chemical Engineering University of Campinas13083-852 CampinasSPBrazil Federal Institute of Education Science and Technology of South of Minas Gerais-IFSULDEMINAS37560-260 Poaso AlegreMGBrazil

The present paper studied numerical and experimentally the transesterification reaction between sunflower oil and ethanol with NaO H catalyst in microchannels with circular obstructions. The micromixer design influence on fluid mixing and oil conversion was investigated for a range of operating conditions: Reynolds number(Re = 0.1–100),Temperature(25–75 °C), ethanol/oil molar ratio(6-12), and catalyst concentration(0.75 wt%–1.25 wt%), using three microchannel configurations(Length = 35 mm; Width = 1500 μm; Height = 200 μm): T-shape – channel without obstructions; MCO – channel with 3 obstructions ensemble – equally disposed over longitudinal length;MWO – channel with 7 obstructions ensemble. The MCO micromixer was based on literature work, and the MWO is a totally new micromixer design. Experimental tests were conducted in similar conditions in microreactors using these micromixers(Length = 411 mm) made of polydimethylsiloxane. The MCO configuration presented the highest performance(mixing index of 0.80 at Re = 100), oil conversion of 81.13% at 75 °C, molar ratio of 9 and catalyst concentration of 1%. Experimental results showed high conversions for MCO and MWO configurations(99.99%) at 50 °C, molar ratio of 9 and catalyst concentration of 1%, with a residence time of 12 s.

关键词： Biodiesel sunflower oil-ethanol Transesterification reaction Circular obstructions Microreactor Numerical simulation

structural Optimization of Metal and Polymer Ore Conveyor Belt Rollers

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Computer Modeling in Engineering & sciences 2022年第12期133卷 601-618页

作者： joao Pedro Ceniz Rodrigo de sá Martins Marco Antonio Luersen Tiago Cousseau Department of Mechanical Engineering Federal University of Technology-Parana(UTFPR)Curitiba81280-340Brazil

Ore conveyor belt rollers operate in harsh environments,making them prone to premature *** service lives are highly dependent on the stress field and bearing misalignment angle,for which limit values are defined in a *** this work,an optimization methodology using metamodels based on radial basis functions is implemented to reduce themass of twomodels of *** a structural point of view,one of the rollers ismade completely of metal,while the other also has some components made of polymeric *** objective of this study is to develop and apply a parametric structural optimization methodology to minimize the mass of the two models of *** represent the mechanical behavior of the rollers,simulations were performed using the finite element *** the numerical optimization process,the variable parameters were the dimensions of the shaft and external *** geometric configuration that corresponded at the same time to the lowest mass and acceptable ranges for the stress and bearingmisalignment angle was *** the proposed methodology,a 32.3% reduction in mass was obtained for a metal roller design and an 18.9% reduction for a polymer *** both cases,the constraints were not *** the all-metal roller,the safety factors for the maximum stress and bearingmisalignment angle were 1.44 and 1.75,respectively,while for the polymer roller the corresponding figures were 1.50 and *** work describes a low-computational-cost optimization methodology for roller designs that have been little studied in the ***,the methodology could be adapted for use with other types of rollers and rollers made of different materials.

关键词： Conveyor belt rollers structural optimization surrogate models radial basis functions

马铃薯在12℃贮藏及在4℃贮后重调贮温其块茎中还原糖的遗传模式

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园艺与种苗 1993年第5期 34-36页

作者： A.da s.pereira 张华

马铃薯薯片色泽是决定消费者对油炸薯片接受力的最重要因素。薯片的褐变主要是美拉尔德(Maillard)反应的结果,即在炸制过程中发生于还原糖(果糖、葡萄糖)和氨基化合物之间的反应,以还原糖的量为限制因子。马铃薯块茎中糖含量取决于诸多... 详细信息

马铃薯薯片色泽是决定消费者对油炸薯片接受力的最重要因素。薯片的褐变主要是美拉尔德(Maillard)反应的结果,即在炸制过程中发生于还原糖(果糖、葡萄糖)和氨基化合物之间的反应,以还原糖的量为限制因子。马铃薯块茎中糖含量取决于诸多因素,既有遗传的又有环境的。多数用于制作薯片的品种的块

关键词：还原糖 ND 无性系低水平还原性糖无性繁殖系品系(育种) 块茎地下茎亲本系

Development of metal organic fromwork-199 immobilized zeolite foam for adsorption of common indoor VOCs

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Journal of Environmental sciences 2017年第5期29卷 321-330页

作者： Vipin K.saini joao Pires school of Environment and Natural Resources Doon UniversityDehradun 248001India Department of Chemistry and Biochemistry Faculty of SciencesUniversity of LisbonLisbon 1749-016Portugal

Reticulated foam shaped adsorbents are more efficient for the removal of volatile organic compounds（VOCs）,particularly from low VOC-concentration indoor air streams. In this study composite structure of zeolite and metal organic frameworks（MOFs）,referred as ZMF,has been fabricated by immobilization of fine MOF-199 powder on foam shaped Zeolite socony Mobil-5（ZsM-5）Zeolitic structure,referred as ZF. The ZMF possess a uniform and well-dispersed coating of MOF-199 on the porous framework of ZF. It shows higher surface area,pore volume,and VOCs adsorption capacity,as compared to ***-fabrication changes in selective adsorption properties of ZMF were studied with three common indoor VOCs（benzene,n-hexane,and cyclohexane）,using gravimetric adsorption technique. The adsorption capacity of ZMF with different VOCs follow the order of benzene 〉 n-hexane 〉 cyclohexane. In comparison with MOF-199 and ZF,the composite structure ZMF shows improvement in selectivity for benzene from other two VOCs. Further,improvement in efficiency and stability of prepared ZMF was found to be associated with its high MOF loading capacity and unique morphological and structural properties. The developed composite structure with improved VOCs removal and recyclability could be a promising material for small to limited scale air pollution treatment units.

关键词： VOCs Adsorption Composite materials selectivity Zeolite foam MOFs HKUsT-1

Molecule-based kinetic modeling by Monte Carlo methods for heavy petroleum conversion

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science China Chemistry 2013年第11期56卷 1608-1622页

作者： de OLIVEIRA Luís.pereira VERsTRAETE Jan J. KOLB Max IFP Energies nouvelles Rond-point de l'échangeur de Solaize-BP 369360 SolaizeFrance Laboratoire de Chimie cole Normale Supérieure69364 Lyon Cedex 07France

A methodology for kinetic modeling of conversion processes is *** proposed approach allows to overcome the lack of molecular detail of the petroleum fractions and to simulate the reactions of the process by means of a two-step *** the first step,a synthetic mixture of molecules representing the feedstock is generated via a molecular reconstruction method,termed sR-REM molecular *** the second step,a kinetic Monte Carlo method,termed stochastic simulation algorithm(ssA),is used to simulate the effect of the conversion reactions on the mixture of *** resulting methodology is applied to the Athabasca vacuum residue *** adequate molecular representation of the vacuum residue is obtained using the sR-REM *** reaction simulations present a good agreement with the laboratory data for Athabasca vacuum residue *** addition,the proposed methodology provides the molecular detail of the vacuum residue conversion throughout the reactions simulations.

关键词： Monte-Carlo molecular reconstruction kinetic modeling stochastic simulation algorithm vacuum residue hydrocracking

Artificial intelligence application in diagnostic gastrointestinal endoscopy-Deus ex machina?

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World Journal of Gastroenterology 2021年第32期27卷 5351-5361页

作者： Fábio pereira Correia Luís Carvalho Lourenço Department of Gastroenterology Hospital Prof.Dr Fernando FonsecaLisbon 2720-276Portugal

The close relationship of medicine with technology and the particular interest in this symbiosis in recent years has led to the development of several computed artificial intelligence(AI)systems aimed at various areas of medicine.A number of studies have demonstrated that those systems allow accurate diagnoses with histological precision,thus facilitating decision-making by clinicians in real *** the field of gastroenterology,AI has been applied in the diagnosis of pathologies of the entire digestive tract and their attached glands,and are increasingly accepted for the detection of colorectal polyps and confirming their histological *** have shown high accuracy,sensitivity,and specificity in relation to expert endoscopists,and mainly in relation to those with less *** applications that are increasingly studied and with very promising results are the investigation of dysplasia in patients with Barrett's esophagus and the endoscopic and histological assessment of colon inflammation in patients with ulcerative *** some cases AI is thus better than or at least equal to human ***,additional studies are needed to reinforce the existing data,and mainly to determine the applicability of this technology in other *** review summarizes the state of the art of AI in gastroenterological pathology.

关键词： Artificial intelligence Computer-aided diagnosis Deep learning gastrointestinal endoscopy Colorectal polyps Dysplasia

Trans-10,cis-12 conjugated linoleic acid reduces neutral lipid content and may affect cryotolerance of in vitro-produced crossbred bovine embryos

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Journal of Animal science and Biotechnology 2014年第4期5卷 391-398页

作者： Ribrio Ivan Tavares.pereira Batista Nadia Rezende Barbosa Raposo Paulo Henrique Almeida Campos-Junior Michele Munk pereira Luiz sergio Almeida Camargo Bruno Campos Carvalho Marco Antonio sundfeld Gama joao Henrique Moreira Viana Federal University of Juiz de Fora Juiz de ForaMG 36036-900Brazil Embrapa Dairy Cattle Research Center Juiz de ForaMG 36038-330Brazil Federal University of Minas Gerais Belo HorizonteMG 31270-901Brazil

Background：Due to high neutral lipids accumulation in the cytoplasm,in vitro-produced embryos from Bos primigenius indicus and their crosses are more sensitive to chilling and cryopreservation than those from Bos primigenius *** objective of the present study was to evaluate the effects of trans-10,cis-12 conjugated linoleic acid（CLA） on the development and cryotolerance of crossbred Bos primigenius taurus x Bos primigenius indicus embryos produced in vitro,and cultured in the presence of fetal calf *** zygotes（n = 1,692）were randomly assigned to one of the following treatment groups：1） Control,zygotes cultured in Charles Rosenkrans 2 amino acid（CR2aa） medium（n = 815） or 2） CLA,zygotes cultured in CR2 aa medium supplemented with 100 μmol/L of trans-10,cis-12 CLA（n =877）.Embryo development（cleavage and blastocyst rates evaluated at days 3 and 8 of culture,respectively）,lipid content at morula stage（day 5） and blastocyst cryotolerance（re-expansion and hatching rates,evaluated 24 and 72 h post-thawing,respectively） were compared between ***,selected mRNA transcripts were measured by Real-Time PCR in blastocyst ***：The CLA treatment had no effect on cleavage and blastocyst rates,or on mRNA levels for genes related to cellular stress and *** the other hand,abundance of mRNA for the 1-acylglycerol-3-phosphate0-acyltransferase-encoding gene（AGPAT）,which is involved in triglycerides synthesis,and consequently neutral lipid content,were reduced by CLA treatment.A significant increase was observed in the re-expansion rate of embryos cultured with trans-10,cis-12 CLA when compared to control（56.3 vs.34.4%,respectively,P = 0.002）.However,this difference was not observed in the hatching rate（16.5 vs.14.0%,respectively,P=0.62）.Conclusions：The supplementation with trans-10,ds-12 CLA isomer in culture medium reduced the lipid content of in vitro produced bovine embryos by reducing the gene expression of 1-acylglycerol 3-phosphate 0

关键词： Blastocysts CLA Crossbred cattle Cryopreservation Lipid content