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Powder metallurgy with space holder for porous titanium implants:A review

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Journal of Materials Science & Technology 2021年第17期76卷 129-149页

作者： Alejandra Rodriguez-Contreras Miquel Punset JoséA.Calero Francisco Javier Gil elisa Ruperez JoséMaría Manero Biomaterials Biomechanics and Tissue Engineering Group(BBT)Department of Materials Science and EngineeringUniversitat Politecnica de Catalunya(UPC)Av.Edurad Maristany 1608019BarcelonaSpain Barcelona Research Centre in Multiscale Science and Engineering Technical University of Catalonia(UPC)Av.Eduard Maristany 10-1408019BarcelonaSpain UPC Innovation and Technology Center(CIT-UPC).Technical University of Catalonia(UPC) C.Jordi Girona 3-108034Barcelona.Spain AMES GROUP SA.Carretera Nacional 340 Pol.Ind."Les Fallulles"08620Sant Vicenc dels HortsBarcelonaSpain Bioengineering Institute for Technology Universitat Intemacional de Catalunyac/Josep Trueta s/n08195BarcelonaSpain

One of the biggest challenges in the biocompatibility of implantable metals is the prevention of the stress shielding effect,which is related to the coupling of the bone-metal mechanical *** stress shielding phenomenon provokes bone resorption and the consequent adverse effects on prosthesis ***,it can be inhibited by adapting the stiffness of the implant *** the use of titanium(Ti)porous structures is a great alternative not only to inhibit this effect but also to improve the osteointegration of orthopedic and dental implants,a brief description of the techniques used for their manufacturing and a review of the current commercialized implants produced from porous Ti assemblies are compiled in this *** powder metallurgy(PM)with space holder(SH)is a powerful technology used to produce porous Ti structures,it is here discussed its potential for the fabrication of medical devices from the perspectives of both design and *** most important parameters of the technique such as the size and shape of the initial metallic particles,the SH and binder type of materials,the compaction pressure of the green form,and in the sintering stage,the temperature,atmosphere,and time are reviewed according to the bibliography ***,the importance of the porosity and its types together with the influence of the mentioned parameters in the final porosity and,consequently,in the ultimate mechanical properties of the structure are ***,a few examples of the PM-SH application for the manufacturing of orthopedic implants are presented.

关键词： Powder metallurgy Space holder method Porous titanium structures Medical devices Stress shielding effect Porous materials permeability Interconnected porosity Porous bone substitute materials Open-cell titanium foams Sintering-dissolution technique

Suspended particulate mercury associated with tidal fluxes in a lagoon environment impacted by cinnabar mining activity(northern Adriatic Sea)

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Journal of Environmental Sciences 2018年第6期30卷 100-113页

作者： Alisè Turritto Alessandro Acquavita Annelore Bezzi Stefano Covelli Giorgio Fontolan elisa Petranich Raffaella Piani Simone Pillon Department of Mathematics and Geoscience University of Trieste Via Weiss 2 34128 Trieste Italy Co.N.I.S.Ma. Consorzio Nazionale Interuniversitario per le Scienze del Mare Piazzale Flaminio 9 00196 Rome Italy ARPA FVG Environmental Protection Agency of Friuli Venezia Giulia Via Cairoli 14 33057 Palmanova (Udine) Italy

The Isonzo River has been demonstrated to be a continuing point source of mercury（Hg）in the Gulf of Trieste although the Idrija mine was last active in 1996. The present study aims to investigate the role of the suspended particulate matter（SPM） associated with tidal fluxes to disperse particulate Hg（PHg） into the Grado coastal lagoon system. PHg concentrations（avg. 3.11 ± 2.62 μg/g, d.w.）, notwithstanding the ebb or flood tides, were significantly higher than the local sediment background（0.13 μg/g）. The relative affinity of Hg for the particulate phase in surface waters was confirmed by higher average distribution coefficient（Kd） values（5.6–6.7）. PHg contents showed the highest values in ebb tide conditions, thus suggesting their origin from the erosion of tidal flats and saltmarshes of the lagoon. When compared to river discharge, high PHg surface concentrations in flood tide are related to rainfall events occurring within the river basin. Results can be used to make an indicative assessment of the amount of Hg bound to SPM which is transported in and out of the lagoon basin following the action of tidal fluxes. A simple estimation provides a negative budget for the Grado lagoon sub-basin which loses between 0.14 and 1.16 kg of PHg during a tidal semi-cycle. This conclusion is in agreement with the evidence of morphological deterioration which has emerged from recent studies on the lagoon environment, and which testifies to a current sedimentary loss from the lagoon into the northern Adriatic Sea.

关键词： Mercury Tidal fluxes Suspended particulate matter Lagoon

Synthesis of palladium-rhodium bimetallic nanoparticles for formic acid dehydrogenation

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Journal of Energy Chemistry 2021年第1期30卷 301-309,I0010页

作者： Ilaria Barlocco Sofia Capelli elisa Zanella Xiaowei Chen Juan JDelgado Alberto Roldan Nikolaos Dimitratos Alberto Villa Dipartimento di Chimica Universitàdegli Studi di MilanoMilan I-20133Italy Departamento de Ciencia de los Materiales Ingeniería Metalúrgica y Química InorgánicaFacultad de CienciasUniversidad de CádizCampus Río San PedroPuerto Real(Cádiz)E-11510Spain School of Chemistry Cardiff UniversityMain BuildingPark PlaceCF103AT CardiffUnited Kingdom Dipartimento di Chimica Industriale e dei Materiali Alma Mater Studiorum Universitàdi BolognaViale Risorgimento 4I-40136 BolognaItaly

Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones by sol immobilization using polyvinyl alcohol(PVA) as protecting agent and NaBH4 as reducing agent,using carbon nanofibers with high graphitization degree(HHT) as the desired *** synthesized catalysts were characterized by means of Transmission Electron Microscopy(TEM) and inductively coupled plasma optical emission spectroscopy(ICP-OES).TEM shows that the average particle size of the Pd-Rh nanoparticles is the range of 3-4 nm,with the presence of few large agglomerated *** bimetallic catalysts,EDX-STEM analysis of individual nanoparticles demonstrated the presence of random-alloyed nanoparticles even in all cases Rh content is lower than the nominal one(calculated Pd:Rh molar ratio:90-10,69-31,49-51,40-60).The catalytic performance of the Pd-Rh catalysts was evaluated in the liquid phase dehydrogenation of formic acid to *** was found that Pd-Rh molar ratio strongly influences the catalytic ***-rich catalysts were more active than Rh-rich ones,with the highest activity observed for Pd90:Rh10(1792 h^(-1)),whereas Pd69:Rh31(921 h^(-1)) resulted the most stable during recycling ***,Pd90:Rh10 was chosen as a representative sample for the liquid-phase hydrogenation of muconic acid using formic acid as hydrogen donor,showing good yield to adipic acid.

关键词： Palladium Rhodium Alloy Formic acid Hydrogen Muconic acid

Analysis of genetic relationship among Arbutus unedo L. genotypes using RAPD and SSR markers

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Journal of Forestry Research 2013年第2期24卷 227-236页

作者： Filomena Gomes Rita Costa Maria M. Ribeiro elisa Figueiredo Jorge M. Canhoto CERNAS Departamento Florestal Escola Superior Agrária Coimbra INRB Instituto Nacional de Recursos Biológicos Departamento de Recursos Naturais e Desenvolvimento Sustentável Escola Superior Agrária Centre of Functional Ecology Department of Life Sciences University of Coimbra

The strawberry tree （Arbutus unedo L.） is an underutilized, drought tolerant, fire resistant species with a south western distribution in Europe, and with ecological and putative socio-economical impact in Portugal and Mediterranean countries. Our aim was to develop an appropriate set of molecular markers to enable genetic diversity to be assessed and to fingerprint Arbutus unedo genotypes for breeding and conservation purposes in Portugal. Twenty-seven trees from a broad geographic range were screened with 20 random amplified polymorphic DNA （RAPD primers） and 11 microsatellite markers （SSR）. The RAPDs generated 124 bands, 57.3% of which were polymorphic, with an expected heterozygosity of 27%. We cross-amplified 11 SSR primers developed for Vaccinium spp., and 5 were found to be polymorphic in A. unedo, with 75% of expected heterozygosity, a number of alleles of 11.6, a null allele frequency of 7.6% and a polymorphic information content of 71%. Although the SSRs were more polymorphic and informative than the RAPDs, both markers displayed high genetic variability with the gathered data. No geographic pattern was observed in the genetic variation distribution based on both marker systems, and the lack of correlation between genetic and geographical matrices was confirmed by Mantel tests. Likely, no correlation was found between pairwise SSR and RAPD band-sharing matrices. These results and their implications on A. unedo breeding and conservation programs are discussed.

关键词： Ericaceae fingerprinting geographic pattern molecular markers strawberry tree.

Is bigger better？ Male body size affects wing-borne courtship signals and mating success in the olive fruit fly, Bactrocera oleae （Diptera： Tephritidae）

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Insect Science 2016年第6期23卷 869-880页

作者： Giovanni Benelli elisa Donati Donato Romano Giacomo Ragni Gabriella Bonsignori Cesare Stefanini Angelo Canale Insect Behaviour Group Department of Agriculture Food and Environment University of Pisa Pisa The BioRobotics Institute Sant'Anna School of Advanced Studies Pontedera Italy

Variations in male body size are known to affect inter- and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor affecting signal strength and mate choice. We evaluated the effect of male size on courtship displays and mating success of the olive fruit fly, Bactrocera oleae （Diptera： Tephritidae）. Wing vibrations performed during successful and unsuccessful courtships by large and small males were recorded by high-speed videos and analyzed through frame-by-frame analysis. Mating success of large and small males was investigated. The effect of male-male competition on mating success was evaluated. Male body size affected both male courtship signals and mating outcomes. Successful males showed wing-borne signals with high frequencies and short interpulse intervals. Wing vibrations displayed by successful large males during copulation attempt had higher frequencies over smaller males and unsuccessful large males. In no-competition conditions, large males achieved higher mating success with respect to smaller ones. Allowing large and small males to compete for a female, large males achieve more mating success over smaller ones. Mate choice by females may be based on selection of the larger males, able to produce high-frequency wing vibrations. Such traits may be indicative of ＂good genes,＂ which under sexual selection could means good social-interaction genes, or a good competitive manipulator of conspecifics.

关键词： communication channels courtship call male-male competition mate choice sexual selection social resources

Plastic occurrence,sources,and impacts in Antarctic environment and biota

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Water Biology and Security 2022年第2期1卷 60-71页

作者： Gabriella Caruso elisa Bergami Neelu Singh Ilaria Corsi Institute of Polar Sciences National Research CouncilMessinaItaly British Antarctic Survey Natural Environment Research CouncilHigh CrossMadingley RoadCambridgeCB30ETUK Department of Life Sciences University of Modena and Reggio EmiliaModenaItaly Norwegian Polar Institute LongyearbyenNorway Department of Physical Earth and Environmental Sciences University of Siena53100SienaItaly

Several studies have documented that plastic pollution is affecting one of the most remote and pristine regions of our planet,*** of different size and polymeric composition have been retrieved in Antarctic sea ice,surface waters and sediments,with microplastics(mostly fibers)found both in terrestrial and marine *** evidence raises concerns about potential detrimental effects on biodiversity and ecosystem *** present review aims to report the most up-to-date knowledge on occurrence and distribution of plastic pollution in the Antarctic environment and biota including interaction with microorganisms,potential sources,and its impact on Antarctic *** understanding of plastic pollution in this polar region will help us define the human footprint in Antarctica and predict future ecological risks.

关键词： Anthropogenic impact Contamination Microplastics Southern ocean Antarctica Occurrence Sources Ecotoxicity Colonization Biosecurity

A Novel Gaussian Extrapolation Approach for 2D Gel Electrophoresis Saturated Protein Spots

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Genomics, Proteomics & Bioinformatics 2012年第6期10卷 336-344页

作者： Massimo Natale Alfonso Caiazzo Enrico M. Bucci elisa Ficarra Department of Control and Computer Engineering Politecnico di Torino BioDigitalValley S.r.l. WIAS Berlin Istituto di Biostrutture e Bioimmagini

Analysis of images obtained from two-dimensional gel electrophoresis （2D-GE） is a topic of utmost importance in bioinformatics research, since commercial and academic software available currently has proven to be neither completely effective nor fully automatic, often requiring manual revision and refinement of computer generated matches. In this work, we present an effective technique for the detection and the reconstruction of over-saturated protein spots. Firstly, the algorithm reveals overexposed areas, where spots may be truncated, and plateau regions caused by smeared and overlapping spots. Next, it reconstructs the correct distribution of pixel values in these overexposed areas and plateau regions, using a two-dimensional least-squares fitting based on a generalized Gaussian distribution. Pixel correction in saturated and smeared spots allows more accurate quantification, providing more reliable image analysis results. The method is validated for *** exposed 2D-GE images, comparing reconstructed spots with the corresponding non-saturated image, demonstrating that the algorithm enables correct spot quantification.

关键词： Image analysis Two-dimensional gel electrophoresis Proteomics Software tools

Singing on the wings! Male wing fanning performances affect female willingness to copulate in the aphid parasitoid Lysiphlebus testaceipes （Hymenoptera： Braconidae： Aphidiinae）

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Insect Science 2016年第4期23卷 603-611页

作者： Giovanni Benelli Nickolas G. Kavallieratos elisa Donati Giulia Giunti Cesare Stefanini Angelo Canale Insect Behavior Group Department of Agriculture Food and Environment University of Pisa Pisa Italy Laboratory of Agricultural Entomology Department of Entomology and Agricultural Zoology Benaki Phytopathological Institute Kifissia Attica Greece The BioRobotics Institute Sant'Anna School of Advanced Studies Pontedera Pisa Italy

Lysiphlebus testaceipes （Hymenoptera： Braconidae： Aphidiinae） is a generalist endoparasitoid attacking more than 100 aphid species. In L. testaceipes, wing fanning is a main male courtship display evoked by a female-borne sex pheromone. However, no information is available on the characteristics and behavioral role of male fanning during courtship in this parasitoid. Here, the courtship behavior of a wild strain ofL. testaceipes was quantified and the male wing fanning performances were analyzed through high-speed video recordings and examined in relation to mating success. Courtship sequence of wild L. testaceipes did not substantially differ from that previously reported for other populations mass reared on aphids. We observed that the male courtship duration did not affect mating success. However, video analysis revealed that the males producing high-frequency fanning signals achieved higher mating success over those that display low-frequency fanning. Wing fanning before successful and unsuccessful courtship differed in amplitude of wing movements and alignment toward the mate, highlighting that frontal courtship positively influence the female mating decisions. This study increases knowledge on sexual behavior in a key parasitoid of aphids, highlighting the importance of wing fanning among the range of sensory modalities used in the sexual communication ofL. testaceipes. From a practical point of view, this information is useful in L. testaceipes-based biocontrol strategies, since it can help to establish parameters for quality checking of mass-reared wasps over time.

关键词： biocontrol agent courtship mating success parasitic wasp sensory ecology sexual communication

On the evaluation of ALD TiO_(2),ZrO_(2) and HfO_(2) coatings on corrosion and cytotoxicity performances

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Journal of Magnesium and Alloys 2021年第5期9卷 1828-1841页

作者： Mirco Peron Susanna Cogo Maria Bjelland Abdulla Bin Afif Anup Dadlani elisa Greggio Filippo Berto Jan Torgersen Department of Industrial and Mechanical Engineering Norwegian University of Science and TechnologyRichard Birkelands vei 2b7034 TrondheimNorway Department of Biology University of PadovaVia Ugo Bassi 58/b35131PadovaItaly

Magnesium alloys have been widely studied as materials for temporary implants,but their use has been limited by their corrosion ***,coatings have been proven to provide an effective *** only little explored in the field,Atomic Layer Deposition(ALD)stands out as a coating technology due to the outstanding film conformality and density ***,we provide first insights into the corrosion behavior and the induced biological response of 100 nm thick ALD TiO_(2),HfO_(2)and ZrO_(2)coatings on AZ31 alloy by means of potentiodynamic polarization curves,electrochemical impedance spectroscopy(EIS),hydrogen evolution and MTS colorimetric assay with L929 *** three coatings improve the corrosion behavior and cytotoxicity of the ***,HfO_(2)coatings were characterized by the highest corrosion resistance and cell viability,slightly higher than those of ZrO_(2)***_(2)was characterized by the lowest corrosion improvements and,though generally considered a biocompatible coating,was found to not meet the demands for cellular applications(it was characterized by grade 3 cytotoxicity after 5 days of culture).These results reveal a strong link between biocompatibility and corrosion resistance and entail the need of taking the latter into consideration in the choice of a biocompatible coating to protect degradable Mg-based alloys.

关键词： Atomic layer deposition(ALD) Coatings Corrosion resistance Cytocompatibility Magnesium