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High Voltage 2021年第5期6卷 822-835页

作者： Erika Stracqualursi rodolfo Araneo Amedeo Andreotti DIAEE-Electrical Engineering Division University of Rome“La Sapienza”RomeItaly Electrical Engineering Department University Federico II of NapoliNapoliItaly

In this study,the implementation of different corona discharge models in a transient program for overhead multiconductor lines based on the implicit Crank‐Nicolson Finite Difference Time Domain method is *** different corona models available in the literature,two empirical models(Gary's and Suliciu's models)and a physics‐based model(Malik's model)are discussed,which are broadly used in EMT programs,and their predictions under fast‐front lightning surges and slow‐front switching impulses are *** authors critically review the dynamic capacitance approach in terms of numerical accuracy,when dealing with slowly varying voltages,and applicability,regarding dispersive models assuming a non‐instantaneous charge‐voltage *** alternative voltage‐controlled generator approach is proposed,which is successfully included in the implicit Crank‐Nicolson *** of the objectives of this study is to show how different corona models may predict overvoltages with huge discrepancies,depending on the transient waveform and the propagation distance,despite the similarity of the q‐v hysteresis *** evident discrepancies between models under fast‐front voltage waves are reported,rather than for switching *** consistency of these results in terms of the models'features and q‐v curves is analysed,highlighting the necessity for new engineering tools for corona simulation of general predictive capability.

关键词： conductor transient dealing

Gold-iridium catalysts for the hydrogenation of biomass derived products

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Chinese Journal of Catalysis 2016年第10期37卷 1771-1775页

作者： Lorenzo Landenna Alberto Villa rodolfo Zanella Claudio Evangelisti Laura Prati 米兰大学化学系墨西哥国立自治大学科学应用与技术开发中心意大利国家研究委员会分子科学技术研究所

Au-Ir and Au-Ru on TiOz catalysts prepared by sequential deposition-precipitation technique were compared with the corresponding monometallics in the hydrogenation of levulinic acid to y-valero]actone. Interestingly the addition of Ao to Ir/TiO2 showed a detrimental effect on the activity of Ir monometallic catalyst whereas a positive synergistic effect was shown in the case of Ru. Both catalysts were reduced under H2 to increase the M0-Au0 interaction, From previous DFT calculations and catalytic test, we addressed the lower activity of Au-lr/TiO2 than that of Ir/TiO2 to the interference of Au into the redox mechanism of lr atoms.

关键词： Levulinic acid hydrogenationGold-irdium catalystGold-ruthenium catalysty-ValerolactoneSynergistic effect

Effects of resource sharing directionality on physiologically integrated clones of the invasive Carpobrotus edulis

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Journal of Plant Ecology 2021年第5期14卷 884-895页

作者： Rubén Portela rodolfo Barreiro Sergio R Roiloa BioCost Group Department of BiologyFaculty of ScienceUniversidadc da Coruna15071 A CorunaSpain

Aims One of the key traits associated with clonal growth in plants is the capacity for physiological integration,which allows resource sharing between connected ramets within a clonal *** transport is expected to occur following a source–sink relationship:from ramets established in rich patches to ramets growing in poor ***,some experiments have shown that acropetal transport(from basal to apical modules)usually exceeds basipetal transport(from apical to basal ramets).In this study,we aimed to determine the resource transport directionality in physiologically integrated modules of the invader Carpobrotus *** We conducted two manipulative experiments under common garden conditions that studied the effect of different nutrient levels located at different positions(basal,medial and apical)on connected and disconnected clonal systems of *** compared the biomass partitioning patterns and final biomass of ramets to elucidate whether the effect of physiological integration is affected by the directionality of the resource *** Findings Results indicate a prevalent acropetal transport of resources in ***,with a developmentally programmed division of labor where basal ramets were specialized in obtaining soil-based resources and apical ramets specialized in aboveground *** biomass partitioning pattern was not affected by the nutrient conditions in which basal or apical ramets were growing,although the highest benefit was achieved by apical ramets growing under the most stressed *** developmentally programmed division of labor is expected to increase the lateral growth of ***,and therefore could have meaningful implications for the expansion of this invasive species.

关键词： biomass partitioning Carpobrotus clonal growth division of labor physiological integration

Expanding treatment strategies for hepatocellular carcinoma patients: postoperative adjuvant transarterial chemoembolization

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Hepatobiliary Surgery and Nutrition 2020年第1期9卷 59-61页

作者： rodolfo Sacco Antonio Facciorusso Gastroenterology Unit Department of Medical SciencesUniversity of FoggiaFoggiaItaly

In spite of the recent improvements in diagnostic and treatment options for hepatocellular carcinoma (HCC) patients, with an increasing number of patients diagnosed in early stage and offered more effective therapies, the high recurrence rates even after radical treatments, such as surgery or radiofrequency ablation, still represent an unsolved issue (1).

关键词： patients hepatocellular treatment

A Model of a Quantum Particle in a Quantum Environment: A Numerical Study

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Communications in Computational Physics 2015年第6期18卷 247-262页

作者： Raffaele Carlone rodolfo Figari Claudia Negulescu Universita Federico II di Napoli Dipartimento di Matematica e Applicazioni“R.Caccioppoli”MSA I-80126 NapoliItaly Universita Federico II di Napoli Dipartimento di Fisica e INFN Sezione di NapoliMSA I-80126 NapoliItaly Universite de Toulouse&CNRS UPSInstitut de Mathematiques de Toulouse UMR 5219F-31062 ToulouseFrance

We define and investigate,via numerical analysis,a one dimensional toymodel of a cloud *** energetic quantum particle,whose initial state is a superposition of two identical wave packets with opposite average momentum,interacts during its evolution and exchanges(small amounts of)energy with an array of localized *** by the interaction with the environment,the initial superposition state turns into an incoherent sum of two states describing the following situation:or the particle is going to the left and a large number of spins on the left side changed their states,or the same is happening on the right *** evolution is reminiscent of what happens in a cloud chamber where a quantum particle,emitted as a spherical wave by a radioactive source,marks its passage inside a supersaturated vapour-chamber in the form of a sequence of small liquid bubbles arranging themselves around a pssible classical trajectory of the particle.

关键词： Schrodinger equation quantum particle+environment model multi-channel point interactions Wilson cloud chamber trace formation decoherence numerical discretization

Yield stress measurements and microstructure of colloidal kaolin powders clusterized and dispersed in different liquids

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Particuology 2009年第6期7卷 438-444页

作者： Dario T.Beruto Alberto Lagazzo rodolfo Botter Roberto Grillo Department of Civil Environmental and Architectural Engineering (DICAT)University of GenoaP.le Kennedy (Fiera del Mare)Pad. D16129-GenoaItaly Artigo S.p.A. loc.Carpeneto17014-Cairo Montenotte (SV)Italy

Rheologicat measurements of four colloidal kaolin powders dispersed in water, paraffinic oil and liquid rubber have been done at solid concentration （9 （VS/VL） in the range 8-33%. In quasi-static conditions the yield stress τ° values were derived. An S-shaped relationship between τ° and （9 exists, that allows to evaluate the percolation threshold θc values. In water θc ranges between 29% and 33%, while it is between 17% and 21% in oil and in liquid rubber. In water the microstructure units, i.e. the primary clusters among kaolin crystallites, are denser and bigger than the ones in the two other liquids. Furthermore, in quasistatic condition, the aqueous microstructure units have less tendency to cling together to form a network that can span all over the liquid phase. The different kaolin dispersions at θ equal to 22% are characterized by yield stress ranging between 7.S Pa and 59 Pa in water, 66-250 Pa in oil and 230-770 Pa in liquid rubber. It has been found that for any kaolin types the log τ°/ θ evaluated near to the percolation threshold is a conservative parameter of the three different liquids. These results are useful to design colloidal dispersions with selected microstructure.

关键词： Yield stress Colloid Dispersions Microstructure units Cluster Kaolin Rheology

Acute hepatitis C in a chronically HIV-infected patient:Evolution of different viral genomic regions

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World Journal of Gastroenterology 2003年第7期9卷 1496-1500页

作者： Diego Flichman Veronica Kott Silvia Sookoian rodolfo Campos Catedra de Virologia Facultad de Farmacia y BioquimicaUniversidad de Buenos AiresArgentina Unidad de Higado Hospital"Dr.Cosme Argerich"Argentina

AIM: To analyze the molecular evolution of different viral genomic regions of HCV in an acute HCV infected patient chronically infected with HIV through a 42-month ***: Serum samples of a chronically HIV infected patient that seroconverted to anti HCV antibodies were sequenced, from the event of superinfection through a period of 17 months and in a late sample (42nd month). Hypervariable genomic regions of HIV (V3 loop of the gp120) and HCV (HVR-1 on the E2 glycoprotein gene) were studied. In order to analyze genomic regions involved in different biological functions and with the cellular immune response, HCV core and NS5A were also chosen to be sequenced. Amplification of the different regions was done by RT-PCR and directly sequenced. Confirmation of sequences was done on reamplified material. Nucleotide sequences of the different time points were aligned with CLUSTAL W 1.5, and the corresponding amino acid ones were ***: Hypervariable genomic regions of both viruses (HVR1 and gp120 V3 loop) presented several nonsynonymous changes but, while in the gp120 V3 loop mutations were detected in the sample obtained right after HCV superinfection and maintained throughout, they occurred following a sequential and cumulative pattern in the HVR1. In the NS5A region of HCV, two amino acid changes were detected during the follow-up period, whereas the core region presented several amino acid replacements, once the HCV chronic infection had been ***: During the HIV-HCV superinfection, each genomic region analyzed shows a different evolutionary *** of the nucleotide substitutions observed are nonsynonymous and clustered in previously described epitopes,thus suggesting an immune-driven evolutionary process.

关键词： Acute Disease Adolescent Amino Acid Sequence Female Genome, Viral HIV HIV Envelope Protein gp120 HIV Infections Hepacivirus Hepatitis C Humans Molecular Sequence Data Research Support, Non-U.S. Gov't Superinfection Viral Nonstructural Proteins Viral Proteins

Differences in physiological integration between invasive and noninvasive introduced clonal species of Carpobrotus

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Journal of Plant Ecology 2019年第6期12卷 972-981页

作者： Sergio R.Roiloa Peter Alpert rodolfo Barreiro BioCost Group Biology DepartmentUniversidade da CoruñaA CoruñaSpain Biology Department University of MassachusettsAmherstMA 01003USA

Aims Clonal growth is associated with invasiveness in introduced plant species,but few studies have compared invasive and noninvasive introduced clonal species to investigate which clonal traits may underlie *** test the hypothesis that greater capacity to increase clonal growth via physiological integration of connected ramets increases invasiveness in clonal plants,we compared the effects of severing connections on accumulation of mass in the two species of the creeping,succulent,perennial,herbaceous genus Carpobrotus that have been introduced on sand dunes along the Pacific Coast of northern California,the highly invasive species Carpobrotus edulis and the co-occurring,noninvasive species Carpobrotus *** Pairs of ramets from four mixed populations of the species from California were grown in a common garden for 3 months with and without severing the stem connecting the *** simulate the effect of clones on soils in natural populations,the older ramet was grown in sand amended with potting compost and the younger in sand *** Findings Severance decreased net growth in mass by~60%in *** and~100%in ***,due mainly to the negative effect of severance on the shoot mass of the younger ramet within a *** to the hypothesis,this suggests that physiological integration increases growth more in the less invasive ***,severance also decreased allocation of mass to roots in the older ramet and increased it in the younger ramet in a pair,and the effect on the younger ramet was about twice as great in *** as in *** indicates that the more invasive species shows greater phenotypic plasticity in response to physiological integration,in particular greater capacity for division of *** could contribute to greater long-term growth and suggests that the division of labor may be a trait that underlies the association between clonal growth and invasiveness in plants.

关键词： biomass allocation Carpobrotus clonal growth physiological integration plant invasions

An experimental model of vitreous motion induced by eye rotations

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Eye and Vision 2015年第1期2卷 85-94页

作者： Andrea Bonfiglio Alberto Lagazzo rodolfo Repetto Alessandro Stocchino Department of Civil Chemical and Environmental EngineeringUniversity of GenoaItalyVia Montallegro 116145 GenoaItaly

Background:During eye rotations the vitreous humour moves with respect to the eye *** relative motion has been suggested to possibly have an important role in inducing degradation of the gel structure,which might lead to vitreous liquefaction and/or posterior vitreous *** of the present work is to study the characteristics of vitreous motion induced by eye ***:We use an experimental setup,consisting of a Perspex model of the vitreous chamber that,for simplicity,is taken to have a spherical *** model is filled with an artificial vitreous humour,prepared as a solution of agar powder and hyaluronic acid sodium salt in deionised water,which has viscoelastic mechanical properties similar to those of the real *** model rotates about an axis passing through the centre of the sphere and velocity measurements are taken on the equatorial plane orthogonal to the axis of rotation,using an optical ***:The results show that fluid viscoelasticity has a strong influence on flow *** particular,at certain frequencies of oscillation of the eye model,fluid motion can be resonantly *** means that fluid velocity within the domain can be significantly larger than that of the ***:The frequencies for which resonant excitation occurs are within the range of possible eye rotations ***,the present results suggest that resonant excitation of vitreous motion is likely to occur in ***,in turn,implies that eye rotations produce large stresses on the retina and within the vitreous that may contribute to the disruption of the vitreous gel *** present results also have implications for the choice of the ideal properties for vitreous substitute fluids.

关键词： Vitreous motion Vitreous dynamics Retinal detachment Viscoelasticity

Population structure and range expansion:the case of the invasive gastropod Cyclope neritea in northwest Iberian Peninsula

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Integrative Zoology 2012年第3期7卷 286-298页

作者： Lucía COUCEIRO Lúa LÓPEZ JoséMiguel RUIZ rodolfo BARREIRO Department of Ecology College of ScienceUniversity of A CoruñaA CoruñaSpain

Biotic invasions have a reputation for unpredictable ***,we report how slight changes in human activity responsible for the introduction and range expansion of a non-native mollusk have led to detectable differences in the genetics of the *** neritea is a non-predatory gastropod introduced to 2 areas of the European Atlantic:the northwest Iberian Peninsula(NWIP)and the French Atlantic coast(FAC).Shellfish seabed farming is intense in both areas but focuses on different commercial *** mitochondrial gene sequences,the lower genetic diversity recorded along the NWIP suggests a more homogeneous range of source populations than in the *** FAC,genetic diversity and haplotype composition in the NWIP correlate with the date of first occurrence of *** at each site rather than with geographical *** this pattern evokes the genetic signature expected under a serial-founder colonization model from a single initial enclave,a comparison with samples from potential source populations suggests that the NWIP probably experienced several independent *** jump dispersal pattern of *** in the NWIP,together with the observation that populations established in the same year are genetically undifferentiated,point to human transport as the most plausible explanation for the current range *** evidence for human-mediated dispersal,*** managed to develop a seemingly non-random genetic pattern in the *** is suggested that caution must be exerted when interpreting genetic patterns in invaders.

关键词： alien species Cyclope neritea cytochrome oxidase I genetic geographic pattern population structure