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A Moving Pseudo-Boundary MFS for Three-dimensional Void detection

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Advances in Applied Mathematics and Mechanics 2013年第4期5卷 510-527页

作者： Andreas Karageorghis daniel Lesnic Liviu marin department of Mathematics and Statistics University of CyprusP.O.Box 205371678 NicosiaCyprus department of AppliedMathematics University of LeedsLeeds LS29JTUK Institute of SolidMechanics Romanian Academy15 ConstantinMilleP.O.Box 1-863010141 Bucharestand Centre for Continuum MechanicsFaculty of Mathematics and Computer ScienceUniversity of Bucharest14 Academiei010014 BucharestRomania

We propose a new moving pseudo-boundary method of fundamental solutions(MFS)for the determination of the boundary of a three-dimensional void(rigid inclusion or cavity)within a conducting homogeneous host medium from overdetermined Cauchy data on the accessible exterior *** algorithm for imaging the interior of the medium also makes use of radial spherical parametrization of the unknown star-shaped void and its centre in three *** also include the contraction and dilation factors in selecting the fictitious surfaces where the MFS sources are to be positioned in the set of unknowns in the resulting regularized nonlinear leastsquares *** feasibility of this new method is illustrated in several numerical examples.

关键词： Void detection inverse problem method of fundamental solutions

Analysis of the genotoxic potential of low concentrations of Malathion on the Allium cepa cells and rat hepatoma tissue culture

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Journal of Environmental Sciences 2015年第10期27卷 102-111页

作者： Jaqueline Bianchi Mario Sérgio Mantovani Maria Aparecida marin.Morales department of Biology Institute of BiosciencesSao Paulo State University(UNESP) department of General Biology Biological Science CentreUniv Estadual de Londrina

Based on the concentration of Malathion used in the field, we evaluated the genotoxic potential of low concentrations of this insecticide on meristematic and F1 cells of Allium cepa and on rat hepatoma tissue culture（HTC cells）. In the A. cepa, chromosomal aberrations（CAs）, micronuclei（MN）, and mitotic index（MI） were evaluated by exposing the cells at 1.5,0.75, 0.37, and 0.18 mg/m L of Malathion for 24 and 48 hr of exposure and 48 hr of recovery time. The results showed that all concentrations were genotoxic to A. cepa cells. However,the analysis of the MI has showed non-relevant effects. Chromosomal bridges were the CA more frequently induced, indicating the clastogenic action of Malathion. After the recovery period, the higher concentrations continued to induce genotoxic effects, unlike the observed for the lowest concentrations tested. In HTC cells, the genotoxicity of Malathion was evaluated by the MN test and the comet assay by exposing the cells at 0.09, 0.009, and0.0009 mg/5 m L culture medium, for 24 hr of exposure. In the comet assay, all the concentrations induced genotoxicity in the HTC cells. In the MN test, no significant induction of MN was observed. The genotoxicity induced by the low concentrations of Malathion presented in this work highlights the importance of studying the effects of low concentrations of this pesticide and demonstrates the efficiency of these two test systems for the detection of genetic damage promoted by Malathion.

关键词： HTC Chromosomal aberration Micronuclei Comet assay Pesticide

Bloch surface eigenstates within the radiation continuum

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Light(Science & Applications) 2013年第1期2卷 113-118页

作者： Chia Wei Hsu Bo Zhen Song-Liang Chua Steven G Johnson John d Joannopoulos marin.Soljacic Research Laboratory of Electronics Massachusetts Institute of TechnologyCambridgeMA 02139USA department of Physics Harvard UniversityCambridgeMA 02138USA department of Mathematics Massachusetts Institute of TechnologyCambridgeMA 02139USA

From detailed numerical calculations,we demonstrate that in simple photonic crystal structures,a discrete number of Bloch surface-localized eigenstates can exist inside the continuum of free-space *** to the free space causes the surface modes to leak,but the forward and back-reflected leakage may interfere destructively to create a perfectly bound surface state with zero *** perform analytical temporal coupled-mode theory analysis to show the generality of such phenomenon and its robustness from variations of system ***,time-reversal invariance,two-fold rotational symmetry and a perfectly reflecting boundary are necessary for these unique states.

关键词： bound state in continuum embedded eigenvalue photonic crystal surface mode

determination of REE,U,Тh,Ba,and Zr in simulated hydrogeological leachates by ICP-AES after matrix solvent extraction

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Journal of Rare Earths 2009年第1期27卷 123-127页

作者： marin.Ayranov Joaquin Cobos Karin Popa Vincenzo V.Rondinella European Commission Joint Research Centre Institute for Transuranium Elements Postfach 2340 76125 Karlsruhe Germany Paul Scherrer Institut CH-5232 Villigen PSI Switzerland "Al.I.Cuza"University Department of Chemistry 11-Carol I Blvd. 700506-Ia■i Romania

A fast, reliable and precise method for the determination of Ba, Zr, Th, U, La, Ce, Eu, Hf and Gd in leaching solutions containing up to 1 mol/L FeCl3 by inductively coupled plasma-atomic emission spectrometry（ICP-AES） was ***-liquid extraction with diethyl ether was applied for selective and quantitative extraction of the iron with a decontamination factor of *** study has enabled the determination of rare earth elements, U, Th Ba, and Zr, from the solution with high iron content with detection limits in the range of 1-24 ng/ml and a precision of 0.9%-4.6 % relative standard *** developed method was simple and was adopted for implementation in a glove box for handling radioactive materials.

关键词： rare earths elements ICP-AES iron

MEC-based architecture for interoperable and trustworthy internet of moving things

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digital Communications and Networks 2023年第1期9卷 270-279页

作者： Jesus Sanchez-Gomez Rafael marin.Perez Ramon Sanchez-Iborra Miguel Angel Zamora department of Information and Communications Engineering University of MurciaMurciaSpain Odin Solutions S.L. MurciaSpain University Center of defense San Javier Air Force BaseMurciaSpain

The expansion of the Internet of Moving Things(IoMT)leads to limitless and continuous working playgrounds exploited by highly dynamic end *** requires the adoption of multi-Radio Access Technologies(RATs)-based strategies to provide IoMT units with ubiquitous *** this end,the development of secure bootstrapping and authentication mechanisms is necessary to permit the secure operation of end *** the transmission and power limitations of these elements,current cryptographic solutions do not address these stringent *** that reason,in the study we present a Multi-Access Edge Computing(MEC)-based endto-end architecture that enables an efficient and secure authentication and key agreement between end devices and network servers over heterogeneous resource-limited networks such as the Low Power Wide Area Networks(LPWANs).Our proposal is based on the Authentication,Authorization,and Accounting(AAA)architecture and the recent Internet Engineering Task Force initiatives Static Context Header Compression and Low-Overhead *** results obtained from experimental tests reveal the validity of the proposal as it enables constrained IoMT devices to gain IPv6 connectivity as well as performs end-to-end secure authentication with notable reliability and controlled latency.

关键词： Internet of moving things LPWAN Authentication LO-CoAP-EAP SCHC

does shifting to professional emergency department staffing affect the decision for chest radiography?

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World Journal of Emergency Medicine 2021年第2期12卷 87-92页

作者： marin.Pavlov Lucija Klobucar Iva Klobučar Kristinazgela Vesna degoricija department of Cardiology Sestre Milosrdnice University Hospital CentreZagreb 10000Croatia Institute of Emergency Medicine Osijek-Baranja CountyOsijek 31000Croatia University of Zagreb School of Medicine Zagreb 10000Croatia department of Medicine Sestre milosrdnice University Hospital CentreZagreb 10000Croatia

BACKGROUNd: The study aims to determine whether shifting to professional emergency department(Ed) teams leads to a higher rate of radiologic ***: We retrospectively analyzed a total of 2,000 patients presenting to the Ed of a tertiary teaching hospital in two time periods: group 1(G1) comprised 1,000 consecutive patients enrolled from december 21, 2012 to January 5, 2013(all patients were examined by an internal medicine specialist);group 2(G2) comprised 1,000 consecutive patients enrolled from december 21, 2018 to January 3, 2019(all patients were examined by an emergency physician).RESULTS: The chest X-ray(CXR) was performed in 40.6% of all patients. There was no difference in the frequency of CXR(38.9% in G1 vs. 42.3% in G2, P=0.152). More CXRs were performed in G2 patients older than 65 years, in female patients older than 65 years, in patients presenting during the evening and night shifts or off-hours, in patients with a history of malignancy, in patients with gastrointestinal bleeding, and in patients with bradycardia, but fewer in patients presenting with arrhythmia. No difference in the rates of pathological CXR was found(47.3% in G1 vs. 52.2% in G2, P=0.186). Compared with G2, higher sensitivity and specificity were obtained for the binary logistic regression model predicting pathological findings in ***: Shifting to professional Ed teams does not increase radiologic workup. By implementing deliberate usage of ultrasound, some self-governing procedures, case-oriented investigations, and center-specific recommendations, unnecessary radiologic workup can be avoided. Professional Ed teams could lead to a higher standard of emergency care.

关键词： Chest radiography Emergency department Emergency physicians Healthcare organization

Contrasting climate drivers of seasonal growth in western vs. eastern Mexican mountain conifer forests

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Forest Ecosystems 2023年第1期10卷 64-72页

作者： marin.Pompa-Garcia J.Julio Camarero Eduardo dVivar-Vivar Laboratorio de dendroecologia Facultad de Ciencias Forestales y AmbientalesUniversidad Juarez del Estado de DurangoRio Papaloapan y Blvd.Durango s/n Col.Valle del SurDurango34120Mexico Instituto Pirenaico de Ecologia(IPE-CSIC) Avda.Montanana 100550192ZaragozaSpain

Hydroclimate affects the radial growth responses of trees, but the drivers of their spatial and population variability are not sufficiently understood. We addressed this issue by sampling several conifer populations located at the same latitude, but at different longitude and elevation in western(W) and eastern(E) Mexican regions. We used dendroecology to disentangle how earlywood width(EW), latewood width(LW) and adjusted LW(LWadj),i.e. the residuals after removing EW influences on LW, responded to climate variables(temperature and precipitation), climate indices(Southern Oscillation Index, SOI, Nino 3.4, Pacific decadal Oscillation, PdO) and a drought index(Standardised Precipitation-Evapotranspiration Index, SPEI). The W species(Pinus herrerae Martinez, Pinus durangensis Martinez, Abies durangensis Martínez and Cupressus lusitanica Mill.) showed lower growth rates than the E species(Pinus hartwegii Lindl., Picea mexicana Martinez, Pseudotsuga menziesii(Mirb.) Franco and Abies vejari Martinez). Growth in W benefits mostly from high precipitation in the prior winter and current spring and it is limited by high temperatures in spring, whereas growth in the E showed similar but weaker ***, positive(negative) correlations were found in radial growth with the Nino 3.4(SOI) and the PdO from the prior to current autumns, which were again stronger in absolute terms in the W than in the E regions,excepting SOI in summer. In the W, P. durangensis and C. lusitanica were the least and most responsive species to spring drought, respectively;whilst P. menziesii and A. vejari were very responsive to spring drought compared to P. hartwegii in the E. Our results suggest greater responsiveness to hydroclimate and atmospheric patterns in the W than in the E region. These findings allow better interpretations of future changes in growth and composition in Mexican conifer forests, considering that climate models forecast warmer spring conditions and increased water s

关键词： drought Earlywood El Nino-Oscillation Latewood

Reassembly of the axon initial segment and nodes of Ranvier in regenerated axons of the central nervous system

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Neural Regeneration Research 2017年第8期12卷 1276-1277页

作者： Miguel A.marin.Matthew N.Rasband department of Neuroscience Baylor College of Medicine HoustonTX USA department of Neurology David Geffen Schoolof Medicine University of California Los Angeles Los Angeles CAUSA

Myelinated axons of the peripheral and central nervous system（PNS＆CNS）are divided into molecularly distinct excitable domains,including the axon initial segment（AIS）and nodes of *** AIS is composed of a dense network of cytoskeletal proteins,cell adhesion molecules,and voltage gated ion channels and is located at the proximal most region of the axon（Koleand Stuart, 2012）.

关键词： node CPT AMP Reassembly of the axon initial segment and nodes of Ranvier in regenerated axons of the central nervous system AIS RGCs

The Effect of Internationalization on Firm Performance and the Role of Cultural,Institutional and Geographical distance ——A Study on Chinese Firms

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The Effect of Internationalization on Firm Performance and t...

作者： marin.Hagemans 上海交通大学

学位级别：硕士

due to the globalization trend,the effects of internationalization are in high interest of many *** research has primarily focused on a linear relationship which has led to contradictive findings in the effect of internationalization on firm ***,the importance of the location of subsidiaries has been underestimated in previous *** study answers the question “How does the degree of internationalization affect firm performance?”,in addition it considered the moderating effect of cultural,institutional and geographical distance on this *** study examined 2174 Chinese firms active in 81 different industries,in an unbalanced dataset between *** on moderating variables was collected via different publicly available *** hypotheses were tested based on 15 statistical models using a fixed-effects *** results show that the relation between degree of internationalization and firm performance is an S-shaped *** negative impact of geographical distance was partially supported while the cultural distance had a reversed effect as *** findings support that different levels of internationalization affect the firm performance in different *** attention should be paid to the diversity in distance between cultures and geographic locations of subsidiaries.

关键词： degree of internationalization firm performance cultural distance geographical distance institutional distance Chinese business diversity S-shape