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Agrobacterium tumefaciens-mediated transformation of Eucalyptus urophylla clone BRS07-01

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Journal of Forestry Research 2020年第2期31卷 507-519页

作者： Gisela manuela de franca Bettencourt Carlos Ricardo Soccol Thais Salete Giovanella Luziane franciscon Daiane Rigoni Kestring Isabel Rodrigues Gerhardt Juliana Degenhardt-Goldbach Department of Bioprocess Engineering and Biotechnology Federal University of ParanaAvenida Cel.Francisco Heraclito dos Santos210CuritibaParanaBrazil Department of Agronomy Federal University of ParanaRua dos Funcionarios1540CuritibaParanaBrazil Embrapa Forestry Estrada da RibeiraKm 111ColomboParanaBrazil Embrapa Agricultural Informatics Av.Andre Tosello209CampinasSao PauloBrazil

Genetic transformation is becoming routine for engineering specific traits in important clones of recalcitrant species such as Eucalyptus;however,the efficiency is still low for most species,so many researchers still use seeds instead of clones as initial *** work aimed to develop a genetic transformation protocol,based on a highly efficient in vitro organogenesis protocol,for an Eucalyptus urophylla clone selected in our breeding *** growth regulators were evaluated for indirect organogenesis and *** a two-step protocol,the combination of callus induction media supplemented with 0.5 μM thidiazuron+0.5 μM naphthaleneacetic acid(NAA)and shoot induction media supplemented with 5.0 μM benzylaminopurine+1.0 lM NAA allowed up to 85.6%shoot formation with more shoots per explants when compared with other *** plants expressing the uidA gene were obtained using Agrobacterium tumefaciens and selected for kanamycin resistance.A RAPD analysis was used to check for somaclonal *** tests using 11 RAPD primers,we did not observe somaclonal variation in the in vitro stages evaluated.

关键词： Eucalyptus Genetic transformation In vitro regeneration Plant growth regulators Somaclonal variation

Production Process and Properties of a Highly Porous Al Alloy Made Using NaCl Droplets as a Space Holder

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 1034-1040页

作者： manuela Covaciu Andrew Richard Kennedy Faculty of Engineering University of Nottingham Faculty of Material Science and Engineering Universitatea Tehnica din Cluj-Napoca School of Engineering Pontificia Universidad Católica de Chile

Porous Al structures have been made using a porogen leaching method but with additional novel steps. In this way, Al-0.25Cu-0.6Si-1.0Mg alloys with interconnected, open cells have been made, with high levels of porosity（up to 89%）. The use of 4 to 5 mm diameter sodium chloride droplets combined with interspersion of the metal powder and droplets in the die and dissolution of the salt before sintering was found to enable easier interspersion of the two components, resulting in good connectivity of the beads via the formation of ‘‘windows＇＇ between the pores, and rapid elimination of salt from the structure. Porous Al with densities in the range of 0.28–0.86 g/cm3 exhibited compressive yield strengths in the range of 0.14 to 7.5 MPa, with no difference being observed between the samples made by this route and by more conventional dissolution of the salt after sintering. These novel steps widen the possibility for porous metal manufacture to other materials, not limited by the need to have a sintering temperature below that for the melting point of salt.

关键词： Aluminium alloy Sodium chloride Porous metal

Live-cell imaging:new avenues to investigate retinal regeneration

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Neural Regeneration Research 2017年第8期12卷 1210-1219页

作者： manuela Lahne David R.Hyde Department of Biological Sciences University of Notre Dame Notre Dame IN USA

Sensing and responding to our environment requires functional neurons that act in concert. Neuronal cell loss resulting from degenerative diseases cannot be replaced in humans, causing a functional impairment to integrate and/or respond to sensory cues. In contrast, zebrafish（Danio rerio） possess an endogenous capacity to regenerate lost neurons. Here, we will focus on the processes that lead to neuronal regeneration in the zebrafish retina. Dying retinal neurons release a damage signal, tumor necrosis factor α, which induces the resident radial glia, the Müller glia, to reprogram and re-enter the cell cycle. The Müller glia divide asymmetrically to produce a Müller glia that exits the cell cycle and a neuronal progenitor cell. The arising neuronal progenitor cells undergo several rounds of cell divisions before they migrate to the site of damage to differentiate into the neuronal cell types that were lost. Molecular and immunohistochemical studies have predominantly provided insight into the mechanisms that regulate retinal regeneration. However, many processes during retinal regeneration are dynamic and require live-cell imaging to fully discern the underlying mechanisms. Recently, a multiphoton imaging approach of adult zebrafish retinal cultures was developed. We will discuss the use of live-cell imaging, the currently available tools and those that need to be developed to advance our knowledge on major open questions in the field of retinal regeneration.

关键词： multiphoton microscopy live-cell imaging zebrafish interkinetic nuclear migration tissue culture retinal regeneration Miiller glia neuronal progenitor cell differentiation phagocytosis

New insights on cholangiocarcinoma

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World Journal of Gastrointestinal Oncology 2010年第3期2卷 136-145页

作者： manuela Gatto Domenico Alvaro Division of Gastroenterology Department of Clinical MedicineUniversity of Rome"Sapienza"Polo Pontino

Cholangiocarcinoma(CCA) is a devastating cancer arising from the neoplastic transformation of the biliary *** is characterized by a progressive increase in incidence and *** only curative therapy is radical surgery or liver transplantation but,unfortunately,the majority of patients present with advanced stage disease,which is not amenable to surgical ***,proposed serum and bile biomarkers could help in the screening and surveillance of categories at risk and in diagnosing CCA at an early *** molecular mechanisms triggering neoplastic transformation and growth of biliary epithelium are still undef ined,but signif icant progress has been achieved in the last few *** review deals with the most recent advances on epidemiology,biology,and clinical management of CCA.

关键词： Cholangiocarcinoma Cholangiocytes Growth factors Proliferation Apoptosis

Sarcopenic obesity:recent consensus and clinical implications in patients with chronic liver disease

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Hepatobiliary Surgery and Nutrition 2023年第3期12卷 417-420页

作者： manuela Merli Saniya Khan Department of Translational and Precision Medicine Sapienza University of RomeRomaItaly

Sarcopenia and obesity are two major public health concerns,particularly in the elderly *** conditions have a significant impact on both the individual’s health and quality of *** is defined as a loss of muscle mass,strength,and function physiologically present with aging,while obesity is an excessive accumulation of body *** these conditions are often considered separately,there is growing recognition that they frequently coexist,may synergistically enhance one another,leading to an increased risk of various chronic diseases and *** obesity(SO)is the term utilized to define the simultaneous occurrence of sarcopenia and obesity(1).Since recently,the lack of common diagnostic criteria for SO has made it difficult to diagnose and manage this condition effectively.

关键词： Sarcopenia obesity sarcopenic obesity liver disease

Analysis of the Vibrissa Parametric Resonance Causing a Signal Amplification during Whisking Behaviour

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Journal of Bionic Engineering 2016年第2期13卷 312-323页

作者： Tatiana Volkova Igor Zeidis Hartmut Witte manuela Schmidt Klaus Zimmermann Technische Universiat Ilmenau Technical Mechanics Group 98693 Max-Planck-Ring 12 Ilmenau Germany Technische Universitat Ilmenau Biomechatronics Group 98693 Max-Planck-Ring 12 Ilmenau Germany Friedrich-Schiller-Universitat Jena Institute of Systematic Zoology and Evolutionary Biology with Phyletic Museum 07743 Erbertstrafle 1 Jena Germany

The paper deals with the mechanical vibrational motion ofvibrissae during natural exploratory behaviour of mammals. The theoretical analysis is based on a mechanical model of a cylindrical beam with circular natural configuration under an applied periodic force at the tip, which corresponds to the surface roughness of an investigated object. The equation of motion of the beam is studied using the Euler-Bemoulli beam theory and asymptotic methods of mechanics. It is shown that from the me- chanical point of view the phenomenon of parametric resonance of the vibrissa is possible. It means that the amplitude of forced vibrations of a vibrissa increases exponentially with time, if it is stimulated within a specific resonance frequency range, which depends on biomechanical parameters of the vibrissa. The most intense parametric resonance occurs, when the excitation frequency is close to the doubled natural frequency of free vibrations. Thus, it may be used to distinguish and amplify specific periodic components of a complex roughness profile during texture discrimination.

关键词： vibrissa whisking vibration tactile sensor beam theory parametric resonance

Microstructure and Mechanical Performance of Ti-6Al-4V Lattice Structures Manufactured via Electron Beam Melting(EBM):A Review

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 183-203页

作者： Giuseppe Del Guercio manuela Galati Abdollah Saboori Paolo Fino Luca Iuliano Department of Management and Production Engineering(DIGEP) Politecnico di TorinoCorso Duca Degli Abruzzi 2410129 TurinItaly Department of Applied Science and Technology(DISAT) Politecnico di TorinoCorso Duca Degli Abruzzi 2410129 TurinItaly Integrated Additive Manufacturing Center(IAM)@Polito Politecnico Di TorinoCorso Duca Degli Abruzzi 2410129 TurinItaly

Electron beam melting(EBM) process is an additive manufacturing process largely used to produce complex metallic components made of high-performance materials for aerospace and medical ***,lattice structures made by Ti-6A1-4V have represented a hot topic for the industrial sectors because of having a great potential to combine lower weights and higher performances that can also be tailored by subsequent heat ***,the little knowledge about the mechanical behaviour of the lattice structures is limiting their *** present work aims to provide a comprehensive review of the studies on the mechanical behaviour of the lattice structures made of *** main steps to produce an EBM part were considered as guidelines to review the literature on the lattice performance:(1) design,(2) process and(3) post-heat ***,the correlation between the geometrical features of the lattice structure and their mechanical behaviour is *** addition,the correlation among the mechanical performance of the lattice structures and the process precision,surface roughness and working temperature are also *** investigation on the studies about the properties of heat-treated lattice structure is also conducted.

关键词： Electron beam melting(EBM) Additive manufacturing(AM) Lattice structures Ti–6Al–4V Mechanical properties Heat treatment

Interaction of silver nanoparticles with mediterranean agricultural soils: Lab-controlled adsorption and desorption studies

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Journal of Environmental Sciences 2019年第9期31卷 205-216页

作者： Laura Torrent Eva Margui Ignasi Queralt manuela Hidalgo Monica Iglesias Department of Chemistry University of Girona C/M. Aurelia Capmany 69 17003 Girona Spain Institute of Environmental Assessment and Water Research (IDAEA-CSIC) C. Jordi Girona 28-26 08034 Barcelona Spain

The production of silver nanoparticles(AgNPs) has increased tremendously during recent years due to their antibacterial and physicochemical properties. As a consequence, these particles are released inevitably into the environment, with soil being the main sink of disposal. Soil interactions have an effect on AgNP mobility, transport and bioavailability. To understand AgNP adsorption processes, lab-controlled kinetic studies were *** tests performed with five different Mediterranean agricultural soils showed that cation exchange capacity and electrical conductivity are the main parameters controlling the adsorption processes. The adsorption kinetics of different sized(40, 75, 100 and 200 nm)and coated(citrate, polyvinylpyrrolidone and polyethyleneglycol(PEG)) AgNPs indicated that these nanoparticle properties have also an effect on the adsorption *** assess the mobility and bioavailability of AgNPs and to determine if their form is maintained during adsorption/desorption processes, loaded soils were submitted to leaching tests three weeks after batch adsorption studies. The DIN 38414-S4 extraction method indicated that AgNPs were strongly retained on soils, and single-particle inductively coupled plasma mass spectrometry confirmed that silver particles maintained their nanoform, except for 100 nm PEG-AgNPs and 40 nm citrate-coated AgNPs. The DTPA(diethylenetriaminepentaacetic acid) leaching test was more effective in extracting silver,but there was no presence of AgNPs in almost all of these leachates.

关键词： Silver nanoparticles Agricultural soils Sorption kinetics Leaching tests Single-particle inductively coupled plasma mass spectrometry

Analyzing the Interplay of Sintering Conditions on Microstructure and Hardness in Indirect Additive Manufacturing of 17-4PH Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1611-1620页

作者： Erika Lannunziata Mohammad Hossein Mosallanejad manuela Galati Gabriele Piscopo Abdollah Saboori Integrated Additive Manufacturing Center Department of Management and Production EngineeringPolitecnico di TorinoCorso Duca Degli Abruzzi 2410129TurinItaly

Indirect additive manufacturing(AM)methods have recently attracted attention from researchers thanks to their great potential for cheap,straightforward,and small-scale production of metallic *** diffusion additive manufacturing(ADAM),a variant of indirect AM methods,is a layer-wise indirect AM process recently developed based on fused deposition modeling and metal injection ***,there is still limited knowledge of the process conditions and material properties fabricated through this process,where sintering plays a crucial role in the final consolidation of ***,this research,for the first time,systematically investigates the impact of various sintering conditions on the shrinkage,relative density,microstructure,and hardness of the 17-4PH ADAM *** this reason,as-washed samples were sintered under different time-temperature *** sample density was evaluated using Archimedes,computed tomography,and image analysis *** outcomes revealed that sintering variables significantly impacted the density of brown 17-4PH Stainless Steel *** results indicated more than 99% relative densities,higher than the value reported by Markforged Inc.(~96%).Based on parallel porosities observed in the computed tomography results,it can be suggested that by modifying the infill pattern during printing,it would be possible to increase the final relative *** microhardness of the sintered samples in this study was higher than that of the standard sample provided by Markforged *** at 1330℃ for 4 h increased the density of the printed sample without compromising its mechanical *** to X-ray diffraction analysis,the standard sample provided by Markforged ***“1330℃—4 h”one had similar stable phases,although copper-rich intermetallics were more abundant in the microstructure of reference *** study is expected to facilitate the adoption of indirect metal AM methods by different sector

关键词： Indirect additive manufacturing Atomic diffusion additive manufacturing 17-4PH stainless steel Computed tomography Sintering