检索结果-南通市图书馆

Comparison of blood rheological models in patient specific cardiovascular system simulations

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

Journal of Hydrodynamics 2017年第2期29卷 293-304页

作者： Anastasios Skiadopoulos Panagiotis Neofytou christos Housiadas thermal Hydraulics and Multiphase Flows Laboratory I.N.RA.S.T.E.SN.C.S.R.

Newtonian, Quemada and Casson blood viscosity models are implemented in order to simulate the rheological behavior of blood under pulsating flow conditions in a patient specific iliac bifurcation. the influence of the applied blood constitutive equations is monitored via the wall shear stress （WSS） distribution, magnitude and oscillations, non-Newtonian importance factors, and viscosity values according to the shear rate. the distribution of WSS on the vascular wall follows a pattern which is independent of the theological model chosen. On the other hand, the WSS magnitude and oscillations are directly related to the blood constitutive equations applied and the shear rate. It is concluded that the Newtonian approximation is satisfactory only in high shear and flow rates. Moreover, the Newtonian model seems to overestimate the possibility for the formation of atherosclerotic lesions or aneurysms at sites of the vascular wall where the WSS are oscillating.

关键词： Key words: Blood flow simulation patient specific geometries geometry reconstruction non-Newtonian models wall shear stress,pulsating flow

RF-based location of partial discharge sources using received signal features

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

High Voltage 2019年第1期4卷 28-32页

作者： Ephraim t.Iorkyase christos tachtatzis Ian A.Glover Robert C.Atkinson Department of Electronic and Electrical Engineering University of StrathclydeRoyal College Building204 George StreetGlasgow G11XWUK Department of Engineering and technology University of HuddersfieldHD13DH HuddersfieldUK

Partial discharges(PDs)are symptomatic of some localised defects in the insulation system of electrical *** activity emits electrical pulses in the form of radio frequency(RF)signals which can be captured using appropriate *** analysis of the measured RF signals facilitates localisation of *** study investigates the plausibility of using purely RF received signal features of PD pulses to locate PD at low cost.A localisation approach based on the analysis of these features has been developed,with the assumption that PDs generate unique RF spatial patterns due to the complexities and nonlinearities of RF *** this approach,two distinct frequency bands which hold different PD information are *** location features are extracted from the main PD signal and the two sub-band ***-based feature selection(CFS)is employed for feature selection and dimensionality *** results show that PD location can be inferred from the features of the PD *** application of CFS to PD data reduces the memory/computational demand and improves localisation accuracy.

关键词： signal features electrical

Interleukin 12/interleukin 23 pathway: Biological basis and therapeutic effect in patients with Crohn's disease

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2018年第36期24卷 4093-4103页

作者： Ioanna Aggeletopoulou Stelios F Assimakopoulos christos Konstantakis christos triantos Division of Gastroenterology Department of Internal MedicineMedical SchoolUniversity of Patras Department of Internal Medicine University Hospital of Patras

Considering that both innate and adaptive immune responses are involved in the pathogenesis of Crohn's disease(CD), novel therapeutic options have significantly been developed. Biological agents represent an important addition to the conventional treatments for immuno-inflammatory conditions, acting as antagonists of adhesion molecules or various inflammatory cytokines. the interleukin 12(IL-12)/IL-23 common pathway has been found to play a determinant role in the induction of inflammation in adaptive immune responses. In particular, IL-23 promotes the differentiation of na?ve t helper cells into th17 phenotype with the concomitant secretion of several inflammatory cytokines such as IL-17 and IL-22, whereas IL-12 induces the th1 polarization and production of critical cytokines such as interferon-γ and tumor necrosis factor. Nowadays, there is increased interest regarding the role of IL-23 as a therapeutic target of CD through the blockage of IL-23 mediated pathways. In this editorial, we focus on the role of IL-12/IL-23 pathway in the regulation of mucosal immunity and in the induction and maintenance of chronic inflammation. In parallel, we critically discuss the available data regarding the therapeutic effect of the IL-12/IL-23 inhibitors and especially of ustekinumab, a human monoclonal antibody which has been recently approved by the United States Food and Drug Administration for the management of moderateto-severe CD and its potential to be used as first-line therapy in everyday clinical practice.

关键词： Crohn’s disease Interleukin 12 Interleukin 23 Monoclonal antibodies Ustekinumab Biological agents Interleukin 12/interleukin 23 blockade

Efficiency limits of concentrating spectral-splitting hybrid photovoltaic-thermal(PV-t)solar collectors and systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2021年第2期10卷 264-277页

作者： Gan Huang Kai Wang christos N.Markides Clean Energy Processes(CEP)Laboratory Department of Chemical EngineeringImperial College LondonLondon SW72AZUK Institute of Refrigeration and Cryogenics Key Laboratory of Refrigeration and Cryogenic Technology of Zhejiang ProvinceZhejiang UniversityHangzhou 310027China

Spectral splitting is an approach to the design of hybrid photovoltaic-thermal(PVt)collectors that promises significant performance ***,the ultimate efficiency limits,optimal PV cell materials and optical filters of spectral-splitting PVt(SSPVt)collectors remain unclear,with a lack of consensus in the *** develop an idealized model of SSPVt collectors and use this to determine their electrical and thermal efficiency limits,and to uncover how these limits can be approached through the selection of optimal PV cell materials and spectral-splitting *** that thermal losses can be minimized,the efficiency limit,optimal PV material and optimal filter all depend strongly on a coefficient w,which quantifies the value of the delivered thermal energy relative to that of the generated *** total(electrical plus thermal)efficiency limit of SSPVt collectors increases at higher w and at higher optical *** optimal spectral-splitting filter is defined by sharp lower-and upper-bound energies;the former always coincides with the bandgap of the cell,whereas the latter decreases at higher *** total effective efficiency limit of SSPVt collectors is over 20%higher than those of either standalone PV modules or standalone St collectors when w is in the range from 0.35 to 0.50 and up to 30%higher at w~*** study provides a method for identifying the efficiency limits of ideal SSPVt collectors and reports these limits,along with guidance for selecting optimal PV materials and spectral-splitting filters under different conditions and in different applications.

关键词： splitting thermal optimal

Modelling monthly soil losses and sediment yields in Cyprus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2016年第8期9卷 766-787页

作者： christos G.Karydas Panos Panagos School of Agriculture Forestry and Natural Environment Aristotle University of ThessalonikiThessalonikiGreece European Commission Joint Research CentreInstitute of Environment and SustainabilityIspraVAItaly

the aim of this study was to map soil erosion on the Mediterranean island of *** G2 model,an empirical model for month-time step erosion assessments,was *** losses in Cyprus were mapped at a 100 m cell size,while sediment yields at a sub-basin scale of 0.62 km^(2) mean *** results indicated a mean annual erosion rate of 11.75 t ha^(−1)y−^(1),with October and November being the most erosive *** 34%of the island’s surface was found to exceed non-sustainable erosion rates(>10 t ha^(−1)y−^(1)),with sclerophyllous vegetation,coniferous forests,and non-irrigated arable land being the most extensive non-sustainable erosive land *** mean sediment delivery ratio(SDR)was found to be 0.26,while the mean annual specific sediment yield(SSY)value for Cyprus was found to be 3.32 t ha^(−1)y−^(1).the annual sediment yield of the entire island was found to be 2.746 Mt y−*** study was the first to provide complete and detailed erosion figures for Cyprus at a country *** geodatabase and all information records of the study are available at the European Soil Data Centre(ESDAC)of the Joint Research Centre(JRC).

关键词： Soil erosion G2 model USLE Gavrilovic digital earth

Nucleic acid vaccines: A taboo broken and prospect for a hepatitis B virus cure

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第41期27卷 7005-7013页

作者： Efthymios P tsounis Athanasia Mouzaki christos triantos Division of Gastroenterology Department of Internal MedicineUniversity of PatrasPatras 26504Greece Division of Hematology Department of Internal MedicineUniversity of PatrasPatras 26504Greece

Although a prophylactic vaccine is available,hepatitis B virus(HBV)remains a major cause of liver-related morbidity and *** treatment options are improving clinical outcomes in chronic hepatitis B;however,true functional cure is currently the exception rather than the *** acid vaccines are among the emerging immunotherapies that aim to restore weakened immune function in chronically infected *** vaccines in particular have shown promising results in vivo by reducing viral replication,breaking immune tolerance in a sustained manner,or even decimating the intranuclear covalently closed circular DNA reservoir,the hallmark of HBV *** DNA vaccines encoding surface antigens administered by conventional injection elicit HBVspecific t cell responses in humans,initial clinical trials failed to demonstrate additional therapeutic benefit when administered with nucleos(t)ide *** an attempt to improve vaccine immunogenicity,several techniques have been used,including codon/promoter optimization,coadministration of cytokine adjuvants,plasmids engineered to express multiple HBV epitopes,or combinations with other *** vaccine delivery by electroporation is among the most efficient strategies to enhance the production of plasmid-derived antigens to stimulate a potent cellular and humoral anti-HBV *** results suggest that DNA vaccination via electroporation efficiently invigorates both arms of adaptive immunity and suppresses serum HBV *** contrast,the study of mRNA-based vaccines is limited to a few in vitro experiments in this *** studies are needed to clarify the prospects of nucleic acid vaccines for HBV cure.

关键词： Chronic hepatitis B therapeutic vaccination Nucleic acid vaccines DNA vaccines Electroporation Immunotherapy

Information Divergence and the Generalized Normal Distribution:A Study on Symmetricity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Mathematics and Statistics 2021年第4期9卷 439-465页

作者： thomas L.toulias christos P.Kitsos Department of Electrical and Electronics Engineering University of West AtticaCampus 1Egaleo12243 AthensGreece Department of Informatics and Computer Engineering University of West AtticaCampus 1Egaleo12243 AthensGreece

this paper investigates and discusses the use of information divergence,through the widely used Kullback–Leibler(KL)divergence,under the multivariate(generalized)γ-order normal distribution(γ-GND).the behavior of the KL divergence,as far as its symmetricity is concerned,is studied by calculating the divergence of γ-GND over the Student’s multivariate t-distribution and vice *** special cases are also given and ***,three symmetrized forms of the KL divergence,i.e.,the Jeffreys distance,the geometric-KL as well as the harmonic-KL distances,are computed between two members of the γ-GND family,while the corresponding differences between those information distances are also discussed.

关键词： Kullback-Leibler divergence Jeffreys distance Resistor-average distance Multivariateγ-order normal distribution Multivariate Student’s t-distribution Multivariate Laplace distribution

toward a new era of hepatitis B virus therapeutics:the pursuit of a functional cure

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第21期27卷 2727-2757页

作者： Efthymios P tsounis Evanthia tourkochristou Athanasia Mouzaki christos triantos Division of Gastroenterology Department of Internal MedicineMedical SchoolUniversity of PatrasPatras 26504Greece Division of Hematology Department of Internal MedicineMedical SchoolUniversity of PatrasPatras 26504Greece

Hepatitis B virus(HBV)infection,although preventable by vaccination,remains a global health problem and a major cause of chronic liver *** current treatment strategies suppress viral replication very efficiently,the optimal endpoint of hepatitis B surface antigen(HBsAg)clearance is rarely ***,the thorny problems of persistent chromatin-like covalently closed circular DNA and the presence of integrated HBV DNA in the host genome are ***,the scientific community has focused on developing innovative therapeutic approaches to achieve a functional cure of HBV,defined as undetectable HBV DNA and HBsAg loss over a limited treatment period.A deeper understanding of the HBV life cycle has led to the introduction of novel direct-acting antivirals that exert their function through multiple mechanisms,including inhibition of viral entry,transcriptional silencing,epigenetic manipulation,interference with capsid assembly,and disruption of HBsAg *** parallel,another category of new drugs aims to restore dysregulated immune function in chronic hepatitis B accompanied by lethargic cellular and humoral *** of innate immunity by pattern-recognition receptor agonists leads to upregulation of antiviral cytokine expression and appears to contribute to HBV *** checkpoint inhibitors and adoptive transfer of genetically engineered t cells are breakthrough technologies currently being explored that may elicit potent HBV-specific t-cell *** addition,several clinical trials are attempting to clarify the role of therapeutic vaccination in this ***,it is increasingly recognized that elimination of HBV requires a treatment regimen based on a combination of multiple *** review describes the rationale for progressive therapeutic interventions and discusses the latest findings in the field of HBV therapeutics.

关键词： Chronic hepatitis B Functional cure Direct-acting antivirals Gene silencing Immunotherapy therapeutic vaccination

Simulation study on the emittance compensation of off-axis emitted beam in RF photoinjector

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2016年第11期40卷 184-190页

作者：黄瑞萱 Chad Mitchell 贾启卡 christos Papadopoulos Fernando Sannibale [1NSRL University of Science and Technology of ChinaHefei 230029China AtAP Lawrence Berkeley National LaboratoryOne Cyclotron RoadBerkeleyCalifornia94720USA

to make full use of the photocathode material and improve its quantum efficiency lifetime, it can be necessary to operate the laser away from the cathode center in photoinjectors. In RF guns, the off-axis emitted beam will see a time-dependent RF effect, which would generate a significant growth in transverse emittance. It has been demonstrated that such an emittance growth can be almost completely compensated by orienting the beam on a proper orbit in the downstream RF cavities along the injector [1]. In this paper we analyze in detail the simulation techniques used in reference [1] and the issues associated with them. the optimization of photoinjector systems involving off-axis beams is a challenging problem. to solve this problem, one needs advanced simulation tools including both genetic algorithms and an efficient algorithm for 3D space charge. In this paper, we report on simulation studies where the two codes AStRA and IMPACt-t are used jointly to overcome these challenges, in order to optimize a system designed to compensate for the emittance growth in a beam emitted off axis.

关键词： photoinjector off-axis emission genetic algorithm AStRA IMPACt-t RF effect emittance compen-sation