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Multiyear analyses of ground-level air contaminants over Paris metropolitan region using real-time observations and air mass backward trajectories

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Particuology 2016年第5期14卷 60-71页

作者： Marie-Cecile G. Chalbot Ioannis Nicolis Chantal Guihenneuc-Jouyaux ilias G. Kavouras University of Arkansas for Medical Sciences Little Rock AR 72205 USA Universite Paris Descartes 75006 Paris Francec University of Alabama at Birmingham Birmingham AL 35294 USA

For the years 2008-2013, particles of diameter 〈 10 and 2.5 μm （PM10 and PM2.5, respectively）, NOx, SO2, and O3 concentrations at urban, suburban, rural, and traffic sites in the Paris metropolitan area were analyzed. Strong spatial variability at traffic and rural sites and relatively uniform profiles at urban and suburban sites for PM10, PM2.5, and O3 were observed. The O3 weekend effect was induced by lower NOx emissions during the weekend, and favored volatile organic compounds （VOCs）-limited atmospheric conditions. In conJunction with low ambient temperature, these conditions could also favor increased formation of secondary particulate nitrates in winter. Winter air pollution events were associated with multiple pollutants, whereas those observed in spring were caused by high PM10 and PM2.5 levels. Back- ward trajectory analyses showed the contribution of sources in Western and Central Europe on days with high PM10, PM2.5, and O3, and a local/national comvonent for NOx and SO2.

关键词： Air quality Megacity Regional transport PM10 PM2.5 Ozone

Secure Packet Video Transmission over Wireless Multimedia Sensor Networks

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China Communications 2008年第2期5卷 59-67页

作者： ilias Politis Michail Tsagkaropoulos Sofia Gouskou Stavros Kotsopoulos Peter Stavroulakis Dept.of Electrical and Computer Engineering University of Patras Ericsson Research Technical University of Crete

This paper proposes a packet scheduling scheme thatoptimizing the coded video transmission overmultipath wireless multimedia sensor networks interms of received video distortion and power efficiencyenhances the security aspects of the *** the aggregate transmission rateavailable at the network cannot support the requiredtransmission rate,the scheduling algorithm can selectivelydrop combinations of video packets prior totransmission to adapt the rate of the sender to thelimitations of the wireless channel *** algorithms are *** Baselinescheme utilizes a novel distortion prediction modeland decides upon which packet can be dropped priorto transmission based on the packet’s impact on thevideo *** addition to the bandwidthlimitations,the Power aware packet scheduling is an extension of the Baseline capable of estimating thepower that will be consumed by each node during thetransmission;hence it can control the power consumptionby selectively drop packets of low importanceto the decoded *** results indicatethe efficiency of the proposed scheduling schemein terms of received video distortion(PSNR)andpower consumption.

关键词： Terms-WMSN packet scheduling power consumption video distortion

On the QoS Assessment of Video Sessions in Heterogeneous 3G-WLAN Networks with Seamless and Secure Mobility Support

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China Communications 2007年第1期4卷 105-119页

作者： ilias Politis Michail Tsagkaropoulos Stavros Kotsopoulos Tasos Dagiuklas Peter Stavroulakis Dept.of Electrical and Computer Engineering University of Patras26500 Greece Dept.of Telecommunications and Network Systems Technical Institute of MessolonghiNafpaktosGreece Technical University of Crete Roumeliotaki 17 str.73100 LentarianaChaniaCreteGreece

Real-time video data transmission is currently emerging as a popular application among mobile users but it is very sensitive to QoS degradation due to packet losses in wireless *** order to achieve service continuity and integrity upon handoffs among heterogeneous networks,provisioning of seamless and secure mobility is ***,in order to reduce the delay and packet losses during vertical handovers we need to employ supportive protocols like context *** this paper we evaluate the QoS of video transmission over a heterogeneous 3G-WLAN *** aggregate video data traffic is represented by a dynamic two-dimensional Markov chain model,which has been evaluated against real video data *** the vertical handover, appropriate AAA handshaking and enhanced mobility management using context transfer have been *** QoS evaluation of video streams was performed based on peak signal-noise ratio(PSNR) measurements,while we analyticallyestimated the number of packet losses during *** results show that both packet loss within the converged network and loss occurrence affecting the perceived video quality is reduced. Moreover,the proposed context transfer scheme minimizes handover delay and the number of lost packet up to 3 times compared to standard AAA handshaking.

关键词： heterogeneous wireless networks multiplexed video traffic RADIUS-AAA,context transfer

Melatonin’s actions are not limited to sleep

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World Journal of Experimental Medicine 2023年第2期13卷 4-6页

作者： Evangelia Venaki Eftychia Koukkou Ioannis ilias Department of Endocrinology Diabetes and MetabolismElena Venizelou HospitalAthens GR-11521Greece

Melatonin is widely available as a supplement,usually for sleep *** consumption of melatonin supplements has increased considerably in recent *** overlooked aspect of melatonin’s administration is the resulting increase in prolactin secretion,via its action on hypothalamic dopaminergic *** believe that since the effect of melatonin on prolactin is tangible,the laboratory finding of hyperprolactinemia could be encountered more often,given the increase in melatonin’s *** is an issue that merits further study.

Multifunctional antiperovskites driven by strong magnetostructural coupling

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npj Computational Materials 2021年第1期7卷 890-898页

作者： Harish K.Singh ilias Samathrakis Nuno MFortunato Jan Zemen Chen Shen Oliver Gutfleisch Hongbin Zhang Institute of Materials Science Technische Universität DarmstadtDarmstadtGermany Faculty of Electrical Engineering Czech Technical UniversityPragueCzech Republic Department of Physics Blackett LaboratoryImperial College LondonLondonUK Materials Recycling and Resource Strategies Fraunhofer IWKSHanauGermany

Based on density functional theory calculations,we elucidated the origin of multifunctional properties for cubic antiperovskites with noncollinear magnetic ground states,which can be attributed to strong isotropic and anisotropic magnetostructural *** 54 stable magnetic antiperovskites M_(3)XZ(M=Cr,Mn,Fe,Co,and Ni;X=selected elements from Li to Bi except for noble gases and 4f rare-earth metals;and Z=C and N),14 are found to exhibit the Γ_(4g)/Γ_(5g)(i.e.,characterized by irreducible representations)antiferromagnetic magnetic configurations driven by frustrated exchange coupling and strong magnetocrystalline *** the magnetic deformation as an effective proxy,the isotropic magnetostructural coupling is characterized,and it is observed that the paramagnetic state is critical to understand the experimentally observed negative thermal expansion and to predict the magnetocaloric ***,the piezomagnetic and piezospintronic effects induced by biaxial strain are *** is revealed that there is not a strong correlation between the induced magnetization and anomalous Hall conductivities by the imposed ***,the anomalous Hall/Nernst conductivities can be significantly tailored by the applied strain due to the fine-tuning of the Weyl points energies,leading to promising spintronic applications.

关键词： deformation coupling structural

Surgical management of spontaneous,lateonset Descemet membrane detachment after penetrating keratoplasty for keratoconus:a case report

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Eye and Vision 2017年第1期4卷 66-69页

作者： Myrsini Petrelli Konstantinos Oikonomakis Konstantinos Andreanos Andreas Mouchtouris ilias Georgalas George Kymionis Department of Ophthalmology University of AthensAthensGreece

Background:To report a surgical method for treating corneal oedema in a case of late-onset Descemet membrane detachment after penetrating *** presentation:A 55-year old patient presented with sudden visual loss in his left eye 28 years after penetrating keratoplasty for ***-lamp biomicroscopy revealed a distortion of the corneal graft anatomy with protrusion of the graft and peripheral thinning and steepening in the residual host tissue,accompanied by corneal graft *** segment optical coherence tomography revealed detachment of Descemet membrane localized to the area of the graft *** proceeded with a full-thickness,partially circumferential incision in the graft-host junction,followed by repositioning and re-suturing of the graft in place,and intracameral air injection in order to achieve reattachment of Descemet ***:Corneal graft repositioning in combination with re-bubbling may represent an effective therapeutic option in keratoconic patients with peripheral thinning in the residual host corneal tissue and subsequent Descemet membrane detachment.

关键词： Keratoconus Penetrating keratoplasty Spontaneous Descemet membrane detachment

Constrained crystals deep convolutional generative adversarial network for the inverse design of crystal structures

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npj Computational Materials 2021年第1期7卷 588-594页

作者： Teng Long Nuno M.Fortunato Ingo Opahle Yixuan Zhang ilias Samathrakis Chen Shen Oliver Gutfleisch Hongbin Zhang Institute of Materials Science Technische Universität DarmstadtDarmstadtGermany

Autonomous materials discovery with desired properties is one of the ultimate goals for materials science,and the current studies have been focusing mostly on high-throughput screening based on density functional theory calculations and forward modeling of physical properties using machine *** the deep learning techniques,we have developed a generative model,which can predict distinct stable crystal structures by optimizing the formation energy in the latent *** is demonstrated that the optimization of physical properties can be integrated into the generative model as on-top screening or backward propagator,both with their own *** the generative models on the binary Bi-Se system reveals that distinct crystal structures can be obtained covering the whole composition range,and the phases on the convex hull can be reproduced after the generated structures are fully relaxed to the *** method can be extended to multicomponent systems for multi-objective optimization,which paves the way to achieve the inverse design of materials with optimal properties.

关键词： properties crystal inverse

Additive manufacturing of antibacterial PLA-ZnO nanocomposites:Benefits,limitations and open challenges

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Journal of Materials Science & Technology 2022年第16期111卷 120-151页

作者： Wei Juene Chong Shirley Shen Yuncang Li Adrian Trinchi Dejana Pejak ilias(Louis)Kyratzis Antonella Sola Cuie Wen School of Engineering RMIT UniversityMelbourneVictoria 3001Australia CSIRO Manufacturing Business Unit ClaytonVictoria 3169Australia

Polymeric biomaterials such as polylactic acid(PLA)play a prominent role in the advancement of biomedical additive manufacturing(AM).PLA offers indeed a very advantageous combination of thermomechanical properties and functional attributes,as it is biobased,biodegradable,biocompatible and easy to ***,PLA can be damaged by common sterilization methods and is sensitive to most chemical disinfectants,and this may impair its widespread *** of the most promising ways to overcome this shortcoming is to provide PLA with embedded antibacterial activity by the addition of appropriate fillers such as zinc oxide(Zn O)*** a detailed introduction to the basic properties of PLA and ZnO nanoparticles,the present review analyzes the main variables that govern the antibacterial activity of PLA-ZnO *** applications and related manufacturing processes are also presented to showcase the importance of having embedded antibacterial functions in demanding applications such as food packaging and wound *** is then placed on the emerging literature of the AM of PLA-ZnO nanocomposites,with a focus on fused filament fabrication(also known as fused deposition modeling).Existing gaps and hurdles related to the development and 3D printing of such composites is critically *** is envisioned that a deeper understanding of the processability,thermo-mechanical behavior,biocompatibility and antibacterial efficacy of additively manufactured PLAZnO nanocomposites will foster their adoption in the biomedical field and,ultimately,in all circumstances where it is crucial to limit infection transmission.

关键词： Additive manufacturing Antibacterial activity Fused filament fabrication Nanocomposite PLA ZnO Fused deposition modeling

Treatment of anterior corneal scarring,following DSAEK graft failure,with combined graft exchange and phototherapeutic keratectomy

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Eye and Vision 2017年第1期4卷 56-58页

作者： George Kymionis Konstantinos Oikonomakis Myrsini Petrelli Konstantinos Andreanos Andreas Mouchtouris ilias Georgalas 1st Department of Ophthalmology University of AthensGeneral Hospital of Athens“G.Gennimatas”154 Mesogion AvAthens 11527Greece

Background:To present a method,alternative to penetrating keratoplasty,for the restoration of impaired corneal clarity with anterior stromal scarring following long-standing corneal graft *** presentation:A 48-year old female who had previously underwent Descemet stripping automated endothelial keratoplasty(DSAEK)for the treatment of pseudophakic bullous keratopathy,presented with longstanding corneal oedema and anterior corneal scarring.A significant improvement in corrected distance visual acuity was demonstrated,as corneal clarity was restored following graft exchange and phototherapeutic keratectomy(PTK).Conclusions:The combination of corneal graft exchange and phototherapeutic keratectomy may represent an effective therapeutic option for long-standing corneal oedema with concomitant anterior corneal scarring after failure of a DSAEK graft.

关键词： DSAEK failure Anterior corneal scar Graft exchange Phototherapeutic keratectomy