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Objective assessment of the effect of pupil size upon the power distribution of multifocal contact lenses

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International Journal of Ophthalmology(English edition) 2017年第1期10卷 103-108页

作者： Eleni Papadatou antonio J.Del Aguila-Carrasco jose J.Esteve-Taboada David Madrid-Costa Alejandro Cervino-Exposito Optometry Research Group University of ValenciaValencia 46100Spain Optics Ⅱ Department Optics and Optometry FacultyComplutense University of MadridMadrid 28037Spain

AIM： To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact ***： Two multifocal contact lenses of center-near design and one multifocal contact lens of center-distance design were used in this study. Their power profiles were measured using the NIMO TR1504 device （LAMBDA-X, Belgium）. Based on their power profiles, the power distribution was assessed as a function of pupil size. For the high addition lenses, the resulting refractive power as a function of viewing distance （far, intermediate, and near） and pupil size was also ***： The power distribution of the lenses was affected by pupil size differently. One of the lenses showed a significant spread in refractive power distribution, from about ？3 D to 0 D. Generally, the power distribution of the lenses expanded as the pupil diameter became greater. The surface of the lens dedicated for each distance varied substantially with the design of the ***： In an experimental basis, our results show how the lenses power distribution is affected by the pupil size and underlined the necessity of careful evaluation of the patient’s visual needs and the optical properties of a multifocal contact lens for achieving the optimal visual outcome.

关键词： multifocal contact lenses pupil size power profiles refractive power distribution

Ethical and Legal Arguments about Telemedicine in Colombia

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Journal of Computer and Communications 2017年第3期5卷 116-128页

作者： jose antonio García Pereánez American University Corporation MedellinColombia University of Antioquia MedellinColombia

This paper makes a reflection of humanistic approach about telemedicine in the cyber culture context, including a debate on the “digital era” and the nature of human communication. It is aimed at interpreting the influence of the technological era in the communication between the emitting subjects and receptors that emerge from communicative relations in telemedicine. This is the result of the analysis on legitimacy and legality of Communication for Health among individuals interacting in the cyberspace, mediated and conceived by modern technologies such as computer science, telematics and cybernetics. Telemedicine, according to ethical and legal proposals, can be subject of criticism because of the displacement of the medical doctor-patient relationship. Bigger distance and asymmetries in the medical act are established, being exposed to the inter-subjective relations of the cyberspace that immerses the patient into a deeper vulnerability, mediated by the technology that overflows him. A literature review through the empirical-analytical method, aimed at describing the impact of telemedicine in users, was done. This technology of recent use in Colombia promises to become a tool to support the solution of some health problems. Its development must be linked to the use of regulations that involve the “must be”, and its application must be decided according to legal principles that take on responsibility on medical doctors and technicians. The inevitable development of medical technology and its application in telemedicine may lead to the vulnerability of ethical principles, and consequently, the harm and misinterpretation of the medical act.

关键词： Medical Act Ethical-Legal Cyberculture Digital Subject Telemedicine

A model of bone adaptation as a topology optimization process with contact

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Journal of Biomedical Science and Engineering 2012年第5期5卷 229-244页

作者： antonio Andrade-Campos antonio Ramos jose A.Simoes Department of Mechanical Engineering Centre for Mechanical Technology&AutomationUniversity of AveiroCampus Universitário de SantiagoAveiroPortugal

Topology optimization is presently used in most diverse scientific, technologic and industrial areas, including biomechanics. Bone remodelling models and structural optimization has mutually provided inspiration for new developments in biomechanics and biomedicine. Considering that bone has the ability to adapt its internal structure to mechanical loading (Wolff’s law and Roux’s paradigm), it is possible to model the behaviour of the bone structure by the use of a topology optimization methodology whose optimization variables can be the relative densities and the orthotropic directions. In this work, the internal bone adaptation of a proximal femur is considered. The bone-remodelling scheme is numerically described by a time-dependent evolutionary procedure with anisotropic material parameters. The remodelling rate equation is obtained from the structural optimization task of maximizing the stiffness subject to a biological cost associated with metabolic maintenance of bone tissue in time. The situation of multiple load conditions is considered for a three-dimensional finite element model of the proximal femur. The bone density distribution of a real femur is used as the initial design for the onset of the remodelling mechanism. Examples of bone adaptation resulting from load changes are presented. The three-dimensional finite element model of the proximal femur with initial bone density distribution was adapted to implant a cementless stem. A remeshing technique is used to assign the bone relative density distribution to the new geometry and mesh. The time adaptation of the bone is assessed considering contact with friction at the bone-stem interface. Results of bone density evolution and osteointegration distribution are obtained.

关键词： Bone remodelling Topology Optimization Finite element Contact Osteointegration

Tropical tree community composition and diversity variation along a volcanic elevation gradient

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Journal of Mountain Science 2022年第12期19卷 3475-3486页

作者： Ruben MARTINEZ-CAMILO Manuel MARTINEZ-MELENDEZ Nayely MARTINEZ-MIELENDEZ Derio antonio JIMENEZ-LOPEZ Mauricio jose-RIOS Unidad Villa Corzo Facultad de IngenieríaUniversidad de Ciencias y Artes de Chiapas30520 Villa CorzoChiapasMexico Instituto de Ciencias Biológicas Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico Eizia A.C. 29045 Tuxtla GutiérrezChiapasMexico Departamento de Conservación de la Biodiversidad El Colegio de la Frontera Sur29290 San Cristóbal de las CasasChiapasMexico Orquidiario y Jardín Botánico de Comitán Secretaría de Medio Ambiente e Historia Natural30106 Comitán de DomínguezChiapasMexico Instituto de Investigación en Gestión de Riesgos y Cambio Climático Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico

Unraveling the factors that determine variation of diversity in tropical mountain systems is a topic for debate in plant *** is especially true in areas where topography is complex due to volcano elevational gradients and where forests are vulnerable to human *** this study we used a set of climatic(temperature,rainfall,and radiation solar),topographic(elevation,slope aspect,and slope orientation)and human disturbance variables to determine their effect on diversity and composition patterns of a tree community,considering three slope aspects of a tropical volcano in southeastern *** sampled trees in seventy 0.1-ha plots distributed on three slope aspects of the Tacanávolcano along an elevational gradient of 1500 to 2500 *** determined diversity patterns(general tree richness,exponential of Shannon index,and pioneer species richness)with linear regression models,and for beta diversity,we used a dissimilarity index(within and between elevational bands 100 m wide).The effect of a set of environmental and human disturbance variables on tree diversity and community composition was analyzed with general linear models and multivariate analyses,*** registered 2,949 individual trees belonging to 176 species and *** average species richness and alpha diversity per plot were 13(standard deviation±6)and 9(±5),*** tree richness and alpha diversity increased in the middle part(unimodal patterns)of the elevational gradient,but pioneer species richness decreased linearly with *** variance explained by general linear models was greater in richness(32%)than in alpha diversity(25.3%).The most important predictor variables were temperature(elevational gradient),which explained the unimodal pattern(richness and alpha diversity increase at intermediate levels of temperature),and slope orientation,which explained the increase in richness and alpha diversity toward the geographic *** temperature had a signific

关键词： Composition Environmental gradient Tree diversity patterns Tropical humid cloud forest Tropical volcanoes

Fiber Optic Intensity-Modulated Sensors： a Review in Biomechanics

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Photonic Sensors 2012年第4期2卷 315-330页

作者： Paulo RORIZ antonio RAMOS jose L. SANTOS jose A. SIMOES Department of Mechanics University of Aveiro 3810-193 Aveiro Portugal Faculty of Sciences University of Porto Rua do Campo Alegre 687 4150-179 Porto Portugal

Fiber optic sensors have a set of properties that make them very attractive in biomechanics. However, they remain unknown to many who work in the field. Some possible causes are scarce information, few research groups using them in a routine basis, and even fewer companies offering turnkey and affordable solutions. Nevertheless, as optical fibers revolutionize the way of carrying data in telecommunications, a similar trend is detectable in the world of sensing. The present review aims to describe the most relevant contributions of fiber sensing in biomechanics since their introduction, from 1960s to the present, focusing on intensity-based configurations. An effort has been made to identify key researchers, research and development （R＆D） groups and main applications.

关键词： Biomechanics fiber optic sensors intensity-modulated sensors

Non-Intrusive Elastic Query Processing in the Cloud

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Journal of Computer Science & Technology 2013年第6期28卷 932-947页

作者： Ticiana L. Coelho da Silva Mario A. Nascimento jose antonio F. de Macedo Flavio R. C. Sousa Javam C. Machado Department of Computing Federal University of Ceara Fortaleza Ceara Brazil Department of Computing Science University of Alberta Edmonton Alberta T6G 2E8 Canada

Cloud computing is a very promising paradigm of service-oriented computing. One major benefit of cloud computing is its elasticity, i.e., the system＇s capacity to provide and remove resources automatically at runtime. For that, it is essential to design and implement an efficient and effective technique that takes full advantage of the system＇s potential flexibility. This paper presents a non-intrusive approach that monitors the performance of relational database management systems in a cloud infrastructure, and automatically makes decisions to maximize the efficiency of the provider＇s environment while still satisfying agreed upon ＂service level agreements＂（SLAs）. Our experiments conducted on Amazon＇s cloud infrastructure, confirm that our technique is capable of automatically and dynamically adjusting the system＇s allocated resources observing the SLA.

关键词： elasticity query processing non-intrusive service level agreement

Anisotropic gold nanoparticles: Preparation and applications in catalysis

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Chinese Journal of Catalysis 2016年第10期37卷 1619-1650页

作者： Peter Priecel Hammed Adekunle Salami Romen Herrera Padilla Ziyi Zhong jose antonio Lopez-Sanchez 利物浦大学化学系可再生能源斯蒂芬森研究所英国利物浦新加坡科技研究局(A*STAR) 化学与工程科学研究所新加坡裕廊岛627833

Despite the high amount of scientific work dedicated to the gold nanoparticles in catalysis, most of the research has been performed utilising supported nanoparticles obtained by traditional impreg‐nation of gold salts onto a support, co‐precipitation or deposition‐precipitation methods which do not benefit from the recent advances in nanotechnologies. Only more recently, gold catalyst scien‐tists have been exploiting the potential of preforming the metal nanoparticles in a colloidal suspen‐sion before immobilisation with great results in terms of catalytic activity and the morphology con‐trol of mono‐and bimetallic catalysts. On the other hand, the last decade has seen the emergence of more advanced control in gold metal nanoparticle synthesis, resulting in a variety of anisotropic gold nanoparticles with easily accessible new morphologies that offer control over the coordination of surface atoms and the optical properties of the nanoparticles （tunable plasmon band） with im‐mense relevance for catalysis. Such morphologies include nanorods, nanostars, nanoflowers, den‐dritic nanostructures or polyhedral nanoparticles to mention a few. In addition to highlighting newly developed methods and properties of anisotropic gold nanoparticles, in this review we ex‐amine the emerging literature that clearly indicates the often superior catalytic performance and amazing potential of these nanoparticles to transform the field of heterogeneous catalysis by gold by offering potentially higher catalytic performance, control over exposed active sites, robustness and tunability for thermal‐, electro‐and photocatalysis.

关键词： Anisotropic metal nanoparticles Gold nanoparticles Gold catalysis Photocatalysis Electrocatalysis Catalytic oxidation Colloidal gold nanoparticles Gold nanorod Gold nanostars Sol immobilisation

Risk factors and classifications of hilar cholangiocarcinoma

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World Journal of Gastrointestinal Oncology 2013年第7期5卷 132-138页

作者： Miguel Angel Suarez-Munoz jose Luis Fernandez-Aguilar Belinda Sanchez-Perez jose antonio Perez-Daga Beatriz Garcia-Albiach Ysabel Pulido-Roa Naiara Marin-Camero Julio Santoyo-Santoyo General Digestive and Transplantation Surgery Service HPB and Liver Transplant UnitUniversity Hospital Carlos Haya29010 MalagaSpain

Cholangiocarcinoma is the second most common primary malignant tumor of the *** cholangiocarcinoma or Klatskin tumor represents more than 50% of all biliary tract cholangiocarcinomas.A wide range of risk factors have been identified among patients with Perihilar cholangiocarcinoma including advanced age,male gender,primary sclerosing cholangitis,choledochal cysts,cholelithiasis,cholecystitis,parasitic infection(Opisthorchis viverrini and Clonorchis sinensis),inflammatory bowel disease,alcoholic cirrhosis,nonalcoholic cirrhosis,chronic pancreatitis and metabolic *** classifications have been used to describe the pathologic and radiologic appearance of *** three systems most commonly used to evaluate Perihilar cholangiocarcinoma are the Bismuth-Corlette(BC) system,the Memorial Sloan-Kettering Cancer Center and the TNM *** BC classification provides preoperative assessment of local *** Memorial Sloan-Kettering cancer center proposes a staging system according to three factors related to local tumor extent:the location and extent of bile duct involvement,the presence or absence of portal venous invasion,and the presence or absence of hepatic lobar *** TNM classification,besides the usual descriptors,tumor,node and metastases,provides additional information concerning the possibility for the residual tumor(R) and the histological grade(G).Recently,in 2011,a new consensus classification for the Perihilar cholangiocarcinoma had been *** consensus was organised by the European Hepato-PancreatoBiliary Association which identified the need for a new staging system for this type of *** classification includes information concerning biliary or vascular(portal or arterial) involvement,lymph node status or metastases,but also other essential aspects related to the surgical risk,such as remnant hepatic volume or the possibility of underlying disease.

关键词： Hilar cholangiocarcinoma Klatskin tumor Perihilar cholangiocarcinoma Bile duct cancer

Watt-scale super-octave mid-infrared intrapulse difference frequency generation

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Light(Science & Applications) 2018年第1期7卷 124-131页

作者： Christian Gaida Martin Gebhardt Tobias Heuermann Fabian Stutzki Cesar Jauregui jose antonio-Lopez Axel Schulzgen Rodrigo Amezcua-Correa Andreas Tunnermann Ioachim Pupeza Jens Limpert Institute of Applied Physics Abbe Center of PhotonicsFriedrich-Schiller-Universitat JenaAlbert-Einstein-Str.1507745 JenaGermany Helmholtz-Institute Jena Frobelstieg 307743 JenaGermany Fraunhofer Institute for Applied Optics and Precision Engineering Albert-Einstein-Str.707745 JenaGermany CREOL College of Optics and PhotonicsUniversity of Central FloridaOrlandoFL 32816USA Max-Planck-Institute of Quantum Optics Hans-Kopfermann-Str.185748 GarchingGermany

The development of high-power,broadband sources of coherent mid-infrared radiation is currently the subject of intense research that is driven by a substantial number of existing and continuously emerging applications in medical diagnostics,spectroscopy,microscopy,and fundamental *** of the major,long-standing challenges in improving the performance of these applications has been the construction of compact,broadband mid-infrared radiation sources,which unify the properties of high brightness and spatial and temporal *** to the lack of such radiation sources,several emerging applications can be addressed only with infrared(IR)-beamlines in largescale synchrotron facilities,which are limited regarding user access and only partially fulfill these ***,we present a table-top,broadband,coherent mid-infrared light source that provides brightness at an unprecedented level that supersedes that of synchrotrons in the wavelength range between 3.7 and 18μm by several orders of *** result is enabled by a high-power,few-cycle Tm-doped fiber laser system,which is employed as a pump at 1.9μm wavelength for intrapulse difference frequency generation(IPDFG).IPDFG intrinsically ensures the formation of carrierenvelope-phase stable pulses,which provide ideal prerequisites for state-of-the-art spectroscopy and microscopy.

关键词： pump coherent difference