950 resultados para IMPLANT CONNECTION


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Rainbow connection number, rc(G), of a connected graph G is the minimum number of colors needed to color its edges so that every pair of vertices is connected by at least one path in which no two edges are colored the same (note that the coloring need not be proper). In this paper we study the rainbow connection number with respect to three important graph product operations (namely the Cartesian product, the lexicographic product and the strong product) and the operation of taking the power of a graph. In this direction, we show that if G is a graph obtained by applying any of the operations mentioned above on non-trivial graphs, then rc(G) a parts per thousand currency sign 2r(G) + c, where r(G) denotes the radius of G and . In general the rainbow connection number of a bridgeless graph can be as high as the square of its radius 1]. This is an attempt to identify some graph classes which have rainbow connection number very close to the obvious lower bound of diameter (and thus the radius). The bounds reported are tight up to additive constants. The proofs are constructive and hence yield polynomial time -factor approximation algorithms.

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This paper investigates the instantaneous spatial higher pair to lower pair substitute-connection which is kinematically equivalent up to acceleration analysis for two smooth surfaces in point contact. The existing first-order equivalent substitute-connection consisting of a Hooke's joint (U-joint) and a spherical joint (S-joint) connected by an additional link is extended up to second-order. A two step procedure is chalked out for achieving this equivalence. First, the existing method is employed for velocity equivalence. In the second step, the two centers of substitution are obtained as a conjugate relationship involving the principal normal curvatures of the surfaces at the contact point and the screw coordinates of the instantaneous screw axis (ISA) of the first-order relative motion. Unlike the classical planar replacement, this particular substitution cannot be done by merely examining the profiles of the contacting surfaces. An illustrative example of a three-link direct-contact mechanism is presented. (C) 2014 Elsevier Ltd. All rights reserved.

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Understanding technology evolution through periodic landscaping is an important stage of strategic planning in R&D Management. In fields like that of healthcare, where the initial R&D investment is huge and good medical product serve patients better, these activities become crucial. Approximately five percentage of the world population has hearing disabilities. Current hearing aid products meet less than ten percent of the global needs. Patent data and classifications on cochlear implants from 1977-2010, show the landscapes and evolution in the area of such implant. We attempt to highlight emergence and disappearance of patent classes over period of time showing variations in cochlear implant technologies. A network analysis technique is used to explore and capture technology evolution in patent classes showing what emerged or disappeared over time. Dominant classes are identified. The sporadic influence of university research in cochlear implants is also discussed.

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A simple microstructural rationale for successful anodization of metallic films into ordered oxide nanostructures has been identified. It applies to three of the most commonly studied systems, Zr, Ti and Al films and can be extended to other such oxides. A dense Zone T or II microstructure, in sputtered films, is the most critical ingredient. While T-substrate > 0.3T(melting) Ching is the simplest route, pressure and plasma heating can also be exploited. Such microstructures are also associated with a unique growth stress signature. (C) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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The degeneration of the outer retina usually causes blindness by affecting the photoreceptor cells. However, the ganglion cells, which consist of optic nerves, on the middle and inner retina layers are often intact. The retinal implant, which can partially restore vision by electrical stimulation, soon becomes a focus for research. Although many groups worldwide have spent a lot of effort on building devices for retinal implant, current state-of-the-art technologies still lack a reliable packaging scheme for devices with desirable high-density multi-channel features. Wireless flexible retinal implants have always been the ultimate goal for retinal prosthesis. In this dissertation, the reliable packaging scheme for a wireless flexible parylene-based retinal implants has been well developed. It can not only provide stable electrical and mechanical connections to the high-density multi-channel (1000+ channels on 5 mm × 5 mm chip area) IC chips, but also survive for more than 10 years in the human body with corrosive fluids.

The device is based on a parylene-metal-parylene sandwich structure. In which, the adhesion between the parylene layers and the metals embedded in the parylene layers have been studied. Integration technology for high-density multi-channel IC chips has also been addressed and tested with dummy and real 268-channel and 1024-channel retinal IC chips. In addition, different protection schemes have been tried in application to IC chips and discrete components to gain the longest lifetime. The effectiveness has been confirmed by the accelerated and active lifetime soaking test in saline solution. Surgical mockups have also been designed and successfully implanted inside dog's and pig's eyes. Additionally, the electrodes used to stimulate the ganglion cells have been modified to lower the interface impedance and shaped to better fit the retina. Finally, all the developed technologies have been applied on the final device with a dual-metal-layer structure.

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The spin dependent cross sections, σT1/2 and σT3/2 , and asymmetries, A and A for 3He have been measured at the Jefferson Lab's Hall A facility. The inclusive scattering process 3He(e,e)X was performed for initial beam energies ranging from 0.86 to 5.1 GeV, at a scattering angle of 15.5°. Data includes measurements from the quasielastic peak, resonance region, and the deep inelastic regime. An approximation for the extended Gerasimov-Drell-Hearn integral is presented at a 4-momentum transfer Q2 of 0.2-1.0 GeV2.

Also presented are results on the performance of the polarized 3He target. Polarization of 3He was achieved by the process of spin-exchange collisions with optically pumped rubidium vapor. The 3He polarization was monitored using the NMR technique of adiabatic fast passage (AFP). The average target polarization was approximately 35% and was determined to have a systematic uncertainty of roughly ±4% relative.

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The results are described of eco-physiological investigations of the broad-pincered (Astacus astacus L.J.) crayfish and the long-pincered (Astacus astacus Esch.) crayfish, conducted in 1963—64 in the Institute of Zoology and Parasitology of the Academy of Science of the Lithuanian SSR, for the purpose of studying the interspecific relationship of these two species. In the course of the investigation were determined: the influence of the temperature of the environment on the consumption of oxygen by full grown individuals of both species and on the respiratory movements of the scaphognathites, the threshold temperatures and the saturation of the water by oxygen, the diel activity in the winter period.

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[EU]Txosten honetan konexio konikodun hortzetako inplante baten eraginkortasuna aztertzen da. Zehatzagoak izanik, inplante bat ahotik kanporatu ahal izateko beharrezkoa den indarra aztertu egiten da, kontuan hartuz aldagai horren balioa ezagutzea ezinbestekoa dela pazientearen osasuna eta konforta ziurtatzeko. Proiektu honek zein eremutan garrantzia edukiko duen ikusteko, lehenik eta behin testuingurua deskribatuko da. Horren ondoren helburu nagusiak eta onura zientifiko-tekniko zein ekonomikoak adieraziko dira. Helburuak lortzeko posibleak diren bide desberdinak aztertuko dira, eta bakoitzaren abantailak eta desabantailak kontuan hartuz kasu honi hobeto egokitzen zaion alternatiba aukeratuko da. Jarraian, metodo horri dagokion azalpenari ekingo zaio, proiektuaren garapenean egindako lanak pausoz pauso deskribatuz. Proiektuaren hasieratik amaierara arte egindako lanen planifikazioa era argi batean adierazteko Gantt diagrama erabiliko da. Bertan hiru etapa nagusi ezberdindu daitezke: saiakuntzen aurre-diseinua, kanpaina esperimentala eta emaitzen interpretazioa. Azkenik, egindako saiakuntzen eta analisien emaitzak laburbilduko dira, horiek dakartzaten ondorioak azalduz. Puntu honekin hasiera batean planteatutako helburuei erantzun bat emango zaie, eta proiektu honen ondoren jarraitu ahal izango diren hurrengo pausoak aipatuko dira.

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Since its inception in the 1930's the Freshwater Biological Association at Windermere, England has been involved in research on African lakes and rivers. Research has included general and multidisciplinary surveys of many lakes including Lake Victoria, Lake Tanganyika, Lake Nyasa (Lake Malawi) and Lake George. The hydrobiology of the River Nile has also been studied. Research into physical and chemical limnology, phytoplankton ecology and primary productivity, invertebrate biology, freshwater fish and fisheries.

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Ecosystem level models are motivated by some combination of scientific and practical concerns. Those models motivated by practical concerns are likely to bear little historical relation to previous models. Mechanisms of interaction between particular species and their ecosystems vary enormously. Some species literally construct their own ecosystems. Others have more or less complex and important interactions with other species so that their presence or absence may alter the ecosystem. Prior information about the natural history of particular species can make ecosystem investigations quicker, cheaper, and more effective. The optimal resource for preparing to deal with the unlimited diversity of questions asked of ecologists would be a large' computerized databank of natural history observations for as many species as possible.

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The Elastomer Visible Implant system (EVI) is a relatively new technique for batch marking fish. The aim of this study was to assess retention rates and the possible effects of tagging on the growth and mortality of barbel, Barbus barbus, (81-197mm, fork length) over approximately 2 months using a syringe injection system.