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

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

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Visual function,performance,and processing of basketball players *** individuals

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Journal of Sport and health Science 2020年第6期9卷 587-594页

作者： Jesús Vera Raimundo Jiménez David cárdenas Beatriz Redondo josé Antonio García Department of Optics Faculty of ScienceUniversity of GranadaGranada 18071Spain Department of Physical Education and Sport Faculty of Sport ScienceUniversity of GranadaGranada 18071Spain Sport and health University Mixed Institute University of GranadaGranada 18071Spain

Background:Athletes tend to have better visuo-motor performance than do sedentary ***,several basic visual-function and perceptual parameters remain unexplored to *** this study,we investigated whether differences exist in visual function,performance,and processing between basketball players and individuals without a sport-involvement ***:A total of 33 healthy men with no visual impairment or pathology were divided into 2 groups,depending on the involvement in sport(semi-professional basketball players and sedentary individuals).We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level,and we checked their visual function,performance,and processing through an extended battery of optometric ***:The 2 groups differed in resting heart-rate variability parameters(pconfirming their dissimilarities in regular time practising sports per *** basketball players showed a closer breakpoint and recovery nearpoint of convergence,a higher fusional-vergence rate,better discriminability halos,and better eye-hand coordination(all p valuesconclusion:These results show evidence that athletes,basketball players in this case,exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds,suggesting an improvement due to the systematic involvement of those skills during basketball practice.

关键词： Exercise Fitness level health heart rate variability Visual skills Team sport

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A Proof of Wedderburn＇s Theorem

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Algebra colloquium 2015年第4期22卷 603-606页

作者： josé Antonio cuenca Mira Departamento de álgebra Geometría y Topología Facultad de Ciencias Universidad de Málaga 29071 Málaga Spain

In this note we first introduce the finite weak herstein condition, which is a property that holds for every finite field. For a field F satisfying the finite weak herstein condition, we then characterize whether all the finite-dimensional division F-algebras are commutative. This gives an alternate proof of Wedderburn＇s Theorem.

关键词： division algebra finite-dimensional algebra finite field Galois extension

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Temperature and Thermal Stress Distribution for Metal Mold in Squeeze casting Process

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Journal of Materials Science & Technology 2008年第3期24卷 347-350页

作者： c.h.Lee S.h.Lee Institute of Technology and Science Chung-Ang University

In the squeeze casting process, loaded high pressure （over approximately 200 MPa） and high temperature influence the thermo-mechanical behavior and performance of the used metal mold. Therefore, to safely maintain the metal molds, the thermo-mechanical characteristics （temperature and thermal stress） of metal mold in the squeeze casting must be investigated. In this paper, temperature and thermal stress distribution of steel mold in squeeze casting process were investigated by using a three-dimensional non-steady heat conduction analysis and a three-dimensional thermal elastic-plastic analysis considering temperature-dependent thermophysical and mechanical properties of the steel mold.

关键词： Squeeze casting Steel mold Thermal stress Thermo-Mechanical analysis

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Presynaptic endoplasmic reticulum architecture and hereditary spastic paraplegia

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Neural Regeneration Research 2024年第3期19卷 485-486页

作者： Juan joséPérez-Moreno Instituto de Biomedicina de Sevilla(IBiS) Hospital Universitario Virgen Del Rocío/CSIC/Universidad de Sevillaand Departamento de Biología CelularFacultad de BiologíaUniversidad de SevillaSevilleSpain

hereditary spastic paraplegia(hSP)is a clinically and genetically heterogeneous neurodegenerative disorder,characterized primarily by progressive spasticity and weakness in the lower *** ients can also experience peripheral neuropathy,cognitive impairment,and other neurological *** date,more than 80 genes have been implicated in hSP,encompassing various cellular components,although mutations in genes encoding endoplasmic reticulum(ER)-shaping proteins are the most prevalent(Parodi et al.,2017).ER-shaping proteins are generally known for regulating the tubulation and curvation of the ER,but most of them show additional functions,including fusion of ER tubules,microtubule-severing,ER autophagy,lipid droplet synthesis,contact sites with other organelles(Öztürk et al.,2020).This highlights the complexity of studying the role of these proteins and the link between ER function and hSP.

关键词： reticulum endoplasmic

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Gravitational waves from compact objects

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Research in Astronomy and Astrophysics 2010年第11期10卷 1071-1099页

作者： josé Antonio de Freitas Pacheco University of Nice-Sophia Antipolis Observatoire de la Cote d'Azur Laboratoire Cassiopée-UMR 6202 BP 4229-F606304-Nice Cedex 4-France

Large ground-based laser beam interferometers are presently in operation both in the USA （LIGO） and in Europe （VIRGO） and potential sources that might be detected by these instruments are revisited. The present generation of detectors does not have a sensitivity high enough to probe a significant volume of the universe and, consequently, predicted event rates are very low. The planned advanced generation of interferometers will probably be able to detect, for the first time, a gravitational sig- nal. Advanced LIGO and EGO instruments are expected to detect few （some）： binary coalescences consisting of either two neutron stars, two black holes or a neutron star and a black hole. In space, the sensitivity of the planned LISA spacecraft constellation will allow the detection of the gravitational signals, even within a ＂pessimistic＂ range of possible signals, produced during the capture of compact objects by supermassive black holes, at a rate of a few tens per year.

关键词： gravitational waves -- neutron stars -- black holes

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Increasing Powers in a Degenerate Parabolic Logistic Equation

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chinese Annals of Mathematics,Series B 2013年第2期34卷 277-294页

作者： jos Francisco RODRIGUES hugo TAVARES Department of Mathematics and cMAF Universidade de LisboaAvenida Professor Gama Pinto 21649-003 LisboaPortugal

The purpose of this paper is to study the asymptotic behavior of the positive solutions of the problem tu- △u=au-b（x）up in Ω×R＋,u（0）=u0,u（t ）｜ Ω=0, as p→ ＋∞, where Ω is a bounded domain, and b（x） is a nonnegative function. The authors deduce that the limiting configuration solves a parabolic obstacle problem, and afterwards fully describe its long time behavior.

关键词： Parabolic logistic equation Obstacle problem Positive solution Increasing power Subsolution and supersolution

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Liver transplantation for alcoholic liver disease: Lessons learned and unresolved issues

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World Journal of Gastroenterology 2015年第39期21卷 10994-11002页

作者： josé Ursic-Bedoya Stéphanie Faure hélène Donnadieu-Rigole Georges-Philippe Pageaux Liver Transplantation Unit Digestive Department Saint Eloi University Hospital University of Montpellier Addictology Department Saint Eloi University Hospital University of Montpellier

The use of liver transplantation(LT) as a treatment for alcoholic liver disease(ALD) has been highly controversial since the beginning. The ever increasing shortage of organs has accentuated the low priority given to patients suffering from ALD, which is considered a "self-inflicted" condition. however, by improving the long-term survival rates, making them similar to those from other indications, and recognizing that alcoholism is a primary disease, ALD has become one of the most common indications for LT in Europe and North America, a situation thought unfathomable thirty years ago. Unfortunately, there are still many issues with the use of this procedure for ALD. There are significant relapse rates, and the consequences of excessive drinking after LT range from asymptomatic biochemical and histological abnormalities to graft failure and death. A minimum three-month period of sobriety is required for an improvement in liver function, thus making LT unnecessary, and to demonstrate the patient's commitment to the project, even though a longer abstinence period does not guarantee lower relapse rates after LT. Recent data have shown that LT is also effective for severe alcoholic hepatitis when the patient is unresponsive to corticosteroids therapy, with low relapse rates in highly selected patients, although these results must be confirmed before LT becomes a standard procedure in this setting. Finally, LT for ALD is accompanied by an increased risk of de novo solid organ cancer, skin cancer, and lymphoproliferative disorders, which has a large impact on the survival rates.

关键词： Liver transplantation Alcoholic liver disease cirr

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MEAT AND MEAT PRODUcTS

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Journal of Integrative Agriculture 2013年第11期12卷 1916-1918页

作者： josé M Lorenzo centro Tecnológico de la carne de Galicia

In recent years, meat quality has assumed a greater consumer significance and public attention. There is growing awareness of the link between diet and health and this is reflected in the demand for more information a... 详细信息

关键词： MEAT AND MEAT PRODUcTS

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Tropical dendrochronology applied to invasive tree species in the Brazilian Atlantic Forest

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Journal of Forestry Research 2021年第1期32卷 91-101页

作者： carolina Nogueira Xavier Daniela Granato-Souza Ana carolina M.c.Barbosa joséReinaldo Moreira da Silva Forest Sciences Department Federal University of Lavras(UFLA)C.P.3037Lavras 37200-000Brazil Department of Geosciences University of ArkansasFayettevilleAR 72701USA

The Atlantic Forest is one of the largest and most biodiverse rainforests of South America but anthropogenic activities are drastically changing these *** invasion of alien or exotic species is one of the greatest threats to *** are few studies of invasive species in tropical Brazilian *** research examines growth and ecological aspects of Syzygium cumini and clitoria fairchildiana,two invasive tree species in the Pedra Branca State Park,an Atlantic Forest remnant in southeastern *** species were successfully dated,indicating an average age of 58 and 31 years,respectively.A positive relationship between growth and precipitation of the previous growing season suggests an ecological adaptive strategy,which could be facilitating their invasion into the *** growth diameter curves indicate slow and fast growth rates for *** and ***,*** release episodes detected in the tree rings indicate increased anthropogenic disturbances over the last 50 years.

关键词： Atlantic Forest biome Invasive species Protected areas Tree rings

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