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1

Emerging Communication Technologies (ECT) Phase 4 Report  

NASA Technical Reports Server (NTRS)

The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Crew Exploration Vehicle (CEV), Advanced Range Technology Working Group (ARTWG), and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures on a 24/7 basis. ECT is a continuation of the Range Information System Management (RISM) task started in 2002. This is the fourth year of the project.

Bastin, Gary L.; Harris, William G.; Marin, Jose A.; Nelson, Richard A.

2005-01-01

2

Emerging Communication Technologies (ECT) Phase 2 Report. Volume 2; Appendices  

NASA Technical Reports Server (NTRS)

The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB

Bastin, Gary L.; Harris, William G.; Chiodini, Robert; Nelson, Richard A.; Huang, PoTien; Kruhm, David A.

2003-01-01

3

Emerging Communication Technologies (ECT) Phase 3 Final Report  

NASA Technical Reports Server (NTRS)

The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB.

Bastin, Gary L.; Harris, William G.; Bates, Lakesha D.; Nelson, Richard A.

2004-01-01

4

Emerging Communication Technologies (ECT) Phase 2 Report. Volume 3; Ultra Wideband (UWB) Technology  

NASA Technical Reports Server (NTRS)

The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB

Bastin, Gary L.; Harris, William G.; Chiodini, Robert; Nelson, Richard A.; Huang, PoTien; Kruhm, David A.

2003-01-01

5

Emerging Communication Technologies (ECT) Phase 2 Report. Volume 1; Main Report  

NASA Technical Reports Server (NTRS)

The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB.

Bastin, Gary L.; Harris, William G.; Chiodini, Robert; Nelson, Richard A.; Huang, PoTien; Kruhm, David A.

2003-01-01

6

Advances in lens implant technology  

PubMed Central

Cataract surgery is one of the oldest and the most frequent outpatient clinic operations in medicine performed worldwide. The clouded human crystalline lens is replaced by an artificial intraocular lens implanted into the capsular bag. During the last six decades, cataract surgery has undergone rapid development from a traumatic, manual surgical procedure with implantation of a simple lens to a minimally invasive intervention increasingly assisted by high technology and a broad variety of implants customized for each patient’s individual requirements. This review discusses the major advances in this field and focuses on the main challenge remaining – the treatment of presbyopia. The demand for correction of presbyopia is increasing, reflecting the global growth of the ageing population. Pearls and pitfalls of currently applied methods to correct presbyopia and different approaches under investigation, both in lens implant technology and in surgical technology, are discussed. PMID:23413369

Kampik, Anselm; Dexl, Alois K.; Zimmermann, Nicole; Glasser, Adrian; Baumeister, Martin; Kohnen, Thomas

2013-01-01

7

RFID technology for human implant devices  

Microsoft Academic Search

This article presents an overview on Radio Frequency Identification (RFID) technology for human implants and investigates the technological feasibility of such implants for locating and tracking persons or for remotely controlling human biological functions. Published results on the miniaturization of implantable passive RFID devices are reported as well as a discussion on the choice of the transmission frequency in wireless

Hervé Aubert

2011-01-01

8

Using Aerospace Technology To Design Orthopedic Implants  

NASA Technical Reports Server (NTRS)

Technology originally developed to optimize designs of composite-material aerospace structural components used to develop method for optimizing designs of orthopedic implants. Development effort focused on designing knee implants, long-term goal to develop method for optimizing designs of orthopedic implants in general.

Saravanos, D. A.; Mraz, P. J.; Davy, D. T.

1996-01-01

9

WHAT IS ECT? DOES ECT WORK?  

E-print Network

? WHAT ARE THE RISKS AND BENEFITS? RESOURCES Electroconvulsive Therapy (ECT) Although ECT can be very to 15 minutes. What is ECT? Electroconvulsive therapy (ECT) is a medical treatment most commonly used

Oliver, Douglas L.

10

Microsystem technologies for ophtalmological implants  

NASA Astrophysics Data System (ADS)

Due to the low power consumption CMOS electronics is ideal for the use in implanted systems. This paper presents two projects working on ophthalmological implants. Both systems are powered by an external RF-field. One system has been developed to measure the intraocular pressure continuously which is important for the therapy of glaucoma patients. The system consists of a micro coil and an integrated pressure transponder chip built into an artificial soft lens. A second example is a very complex system for epiretinal stimulation of the nerve cells of the retina. With such a system it might be possible to give blind people that are suffering from retinitis pigmentosa some visual contact to their surrounding.

Mokwa, Wilfried

2003-01-01

11

TOPICAL REVIEW: Microsystem technologies for implantable applications  

NASA Astrophysics Data System (ADS)

Microsystem technologies (MST) have become the basis of a large industry. The advantages of MST compared to other technologies provide opportunities for application in implantable biomedical devices. This paper presents a general and broad literature review of MST for implantable applications focused on the technical domain. A classification scheme is introduced to order the examples, basic technological building blocks relevant for implantable applications are described and finally a case study on the role of microsystems for one clinical condition is presented. We observe that the microfabricated parts span a wide range for implantable applications in various clinical areas. There are 94 active and 67 commercial 'end items' out of a total of 142. End item refers to the total concept, of which the microsystem may only be a part. From the 105 active end items 18 (13% of total number of end items) are classified as products. From these 18 products, there are only two for chronic use. The number of active end items in clinical, animal and proto phase for chronic use is 17, 13 and 20, respectively. The average year of first publication of chronic end items that are still in the animal or clinical phase is 1994 (n = 7) and 1993 (n = 11), respectively. The major technology market combinations are sensors for cardiovascular, drug delivery for drug delivery and electrodes for neurology and ophthalmology. Together these form 51% of all end items. Pressure sensors form the majority of sensors and there is just one product (considered to be an implantable microsystem) in the neurological area. Micro-machined ceramic packages, glass sealed packages and polymer encapsulations are used. Glass to metal seals are used for feedthroughs. Interconnection techniques such as flip chip, wirebonding or conductive epoxy as used in the semiconductor packaging and assembly industry are also used for manufacturing of implantable devices. Coatings are polymers or metal. As an alternative to implantable primary batteries, rechargeable batteries were introduced or concepts in which energy is provided from the outside based on inductive coupling. Long-term developments aiming at autonomous power are, for example, based on electrostatic conversion of mechanical vibrations. Communication with the implantable device is usually done using an inductive link. A large range of materials commonly used in microfabrication are also used for implantable microsystems.

Receveur, Rogier A. M.; Lindemans, Fred W.; de Rooij, Nicolaas F.

2007-05-01

12

Evaluating the Feasibility of Using Remote Technology for Cochlear Implants  

ERIC Educational Resources Information Center

The use of remote technology to provide cochlear implant services has gained popularity in recent years. This article contains a review of research evaluating the feasibility of remote service delivery for recipients of cochlear implants. To date, published studies have determined that speech-processor programming levels and other objective tests…

Goehring, Jenny L.; Hughes, Michelle L.; Baudhuin, Jacquelyn L.

2012-01-01

13

Ion sources for ion implantation technology (invited)  

SciTech Connect

Ion sources for ion implantation are introduced. The technique is applied not only to large scale integration (LSI) devices but also to flat panel display. For LSI fabrication, ion source scheduled maintenance cycle is most important. For CMOS image sensor devices, metal contamination at implanted wafer is most important. On the other hand, to fabricate miniaturized devices, cluster ion implantation has been proposed to make shallow PN junction. While for power devices such as silicon carbide, aluminum ion is required. For doping processes of LCD fabrication, a large ion source is required. The extraction area is about 150 cm × 10 cm, and the beam uniformity is important as well as the total target beam current.

Sakai, Shigeki, E-mail: sakai-shigeki@nissin.co.jp; Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki [Nissin Ion Equipment co., ltd, 575 Kuze-Tonoshiro-cho Minami-ku, Kyoto 601-8205 (Japan)] [Nissin Ion Equipment co., ltd, 575 Kuze-Tonoshiro-cho Minami-ku, Kyoto 601-8205 (Japan)

2014-02-15

14

ECT IN NEUROLOGICAL COUNDITIONS  

PubMed Central

It is a myth that electroconvulsive therapy (ECT) produces greater side effects and worsens the neurological condition when used in neurologically ill patients. With the advancement and sophistication in ECT practice standards and modification procedures, it can be safely administered either to treat selected neurological conditions or the co-morbid psychiatric illnesses without additional risks. However ECT should be administered only after thorough evaluation of risks and benefits in such individuals. PMID:21206577

Girish, K.; Gangadhar, B.N.; Janakiramaiah, N.

2002-01-01

15

Study on application of aerospace technology to improve surgical implants  

NASA Technical Reports Server (NTRS)

The areas where aerospace technology could be used to improve the reliability and performance of metallic, orthopedic implants was assessed. Specifically, comparisons were made of material controls, design approaches, analytical methods and inspection approaches being used in the implant industry with hardware for the aerospace industries. Several areas for possible improvement were noted such as increased use of finite element stress analysis and fracture control programs on devices where the needs exist for maximum reliability and high structural performance.

Johnson, R. E.; Youngblood, J. L.

1982-01-01

16

Ion implantation of graphene-toward IC compatible technologies.  

PubMed

Doping of graphene via low energy ion implantation could open possibilities for fabrication of nanometer-scale patterned graphene-based devices as well as for graphene functionalization compatible with large-scale integrated semiconductor technology. Using advanced electron microscopy/spectroscopy methods, we show for the first time directly that graphene can be doped with B and N via ion implantation and that the retention is in good agreement with predictions from calculation-based literature values. Atomic resolution high-angle dark field imaging (HAADF) combined with single-atom electron energy loss (EEL) spectroscopy reveals that for sufficiently low implantation energies ions are predominantly substitutionally incorporated into the graphene lattice with a very small fraction residing in defect-related sites. PMID:24059439

Bangert, U; Pierce, W; Kepaptsoglou, D M; Ramasse, Q; Zan, R; Gass, M H; Van den Berg, J A; Boothroyd, C B; Amani, J; Hofsäss, H

2013-10-01

17

Optimal design of composite hip implants using NASA technology  

NASA Technical Reports Server (NTRS)

Using an adaptation of NASA software, we have investigated the use of numerical optimization techniques for the shape and material optimization of fiber composite hip implants. The original NASA inhouse codes, were originally developed for the optimization of aerospace structures. The adapted code, which was called OPORIM, couples numerical optimization algorithms with finite element analysis and composite laminate theory to perform design optimization using both shape and material design variables. The external and internal geometry of the implant and the surrounding bone is described with quintic spline curves. This geometric representation is then used to create an equivalent 2-D finite element model of the structure. Using laminate theory and the 3-D geometric information, equivalent stiffnesses are generated for each element of the 2-D finite element model, so that the 3-D stiffness of the structure can be approximated. The geometric information to construct the model of the femur was obtained from a CT scan. A variety of test cases were examined, incorporating several implant constructions and design variable sets. Typically the code was able to produce optimized shape and/or material parameters which substantially reduced stress concentrations in the bone adjacent of the implant. The results indicate that this technology can provide meaningful insight into the design of fiber composite hip implants.

Blake, T. A.; Saravanos, D. A.; Davy, D. T.; Waters, S. A.; Hopkins, D. A.

1993-01-01

18

The Ect2 Rho Guanine Nucleotide Exchange Factor Is Essential for Early Mouse Development and Normal Cell Cytokinesis and Migration  

PubMed Central

Ect2 is a member of the human Dbl family of guanine nucleotide exchange factors (RhoGEFs) that serve as activators of Rho family small GTPases. Although Ect2 is one of at least 25 RhoGEFs that can activate the RhoA small GTPase, cell culture studies using established cell lines determined that Ect2 is essential for mammalian cell cytokinesis and proliferation. To address the function of Ect2 in normal mammalian development, we performed gene targeting to generate Ect2 knockout mice. The heterozygous Ect2 +/– mice showed normal development and life span, indicating that Ect2 haplodeficiency was not deleterious for development or growth. In contrast, Ect2 –/– embryos were not found at birth or postimplantation stages. Ect2 –/– blastocysts were recovered at embryonic day 3.5 but did not give rise to viable outgrowths in culture, indicating that Ect2 is required for peri-implantation development. To further assess the importance of Ect2 in normal cell physiology, we isolated primary fibroblasts from Ect2 fl/fl embryos (MEFs) and ablated Ect2 using adenoviral delivery of Cre recombinase. We observed a significant increase in multinucleated cells and accumulation of cells in G2/M phase, consistent with a role for Ect2 in cytokinesis. Ect2 deficiency also caused enlargement of the cytoplasm and impaired cell migration. Finally, although Ect2-dependent activation of RhoA has been implicated in cytokinesis, Ect2 can also activate Rac1 and Cdc42 to cause growth transformation. Surprisingly, ectopic expression of constitutively activated RhoA, Rac1, or Cdc42, known substrates of Ect2, failed to phenocopy Ect2 and did not rescue the defect in cytokinesis caused by loss of Ect2. In summary, our results establish the unique role of Ect2 in development and normal cell proliferation. PMID:22701760

Cook, Danielle R.; Solski, Patricia A.; Bultman, Scott J.; Kauselmann, Gunther; Schoor, Michael; Kuehn, Ralf; Friedman, Lori S.; Cowley, Dale O.; Van Dyke, Terry; Yeh, Jen Jen; Johnson, Leisa

2011-01-01

19

Research on Factors of Influencing ECT Image Reconstruction  

Microsoft Academic Search

As a measure technology for testing parameters of multi-phase flow, electrical capacitance tomography (ECT) has the characteristics of non -intrusion, non -radiation, low cost, fast response, easy to implement. The quality and rate of image reconstruction are critical for application of ECT in practical industries. In this paper, the factors including numberof pixel, shape of finite element, number of electrode

Yanli Gao; Qing Xu; Feng Zhou

2007-01-01

20

Implants  

MedlinePLUS

... vs. Alternatives Implants are devices that replace the roots of missing teeth. They are used to support ... confidence. There are several types of implants, including: Root form Subperiosteal Mini Root-form implants are the ...

21

Evolution of Ion Implantation Technology and its Contribution to Semiconductor Industry  

SciTech Connect

Industrial aspects of the evolution of ion implantation technology will be reviewed, and their impact on the semiconductor industry will be discussed. The main topics will be the technology's application to the most advanced, ultra scaled CMOS, and to power devices, as well as productivity improvements in implantation technology. Technological insights into future developments in ion-related technologies for emerging industries will also be presented.

Tsukamoto, Katsuhiro [Mitsubishi Electric Corporation (Japan); Kuroi, Takashi; Kawasaki, Yoji [Renesas Electronics Corporation (Japan)

2011-01-07

22

Science and technology of biocompatible thin films for implantable biomedical devices.  

SciTech Connect

This presentation focuses on reviewing research to develop two critical biocompatible film technologies to enable implantable biomedical devices, namely: (1) development of bioinert/biocompatible coatings for encapsulation of Si chips implantable in the human body (e.g., retinal prosthesis implantable in the human eye) - the coating involves a novel ultrananocrystalline diamond (UNCD) film or hybrid biocompatible oxide/UNCD layered films; and (2) development of biocompatible films with high-dielectric constant and microfabrication process to produce energy storage super-capacitors embedded in the microchip to achieve full miniaturization for implantation into the human body.

Li, W.; Kabius, B.; Auciello, O.; Materials Science Division

2010-01-01

23

High density ion implanted contiguous disk bubble technology  

NASA Astrophysics Data System (ADS)

During the past year we have advanced the state-of-the-art in several areas of magnetic bubble technology. The main thrust of our research has been to advance ion implanted contiguous disk devices because these devices offer order of magnitude higher bit density than presently manufactured bubble devices. We succeeded in several regards. Noteworthy accomplishments include demonstration of bubble propagation in devices having 4 sq micron bit cells and exhibiting operating margins equal to those of today's manufactured devices. These devices were demonstrated to operate from 0 C to 120 C, the limits of our present testing capabilities. A major factor in this success was our development of new epitaxial garnet materials which exhibited isotropic magnetostrictive properties -- a feature previously not obtained. In addition to the work on bubble propagation we made significant progress on demonstrating a fully operational contiguous disk chip, complete with bubble generators, transfer gates and stretcher/detectors. All components have now been demonstrated to operate with good overlapping margins and a complete chip has been designed and fabricated. We are in the process of testing it.

Kryder, M. H.; Greve, D. W.; Guzman, A.; Jo, S. C.; Ramesh, M.

1987-10-01

24

Electroconvulsive therapy after maxillofacial metallic implants.  

PubMed

A growing body of literature suggests that electroconvulsive therapy (ECT) can be safely utilized in patients with craniofacial metallic implants. Here we provide radiographic images and the clinical course of a 49-year-old woman with both maxillary and mandibular metallic implants who safely received ECT. PMID:24553317

Freeman, G Mark; Perry, Matthew T; Manatt, George S; Cristancho, Pilar

2014-03-01

25

ECT Stimulus Parameters: Rethinking Dosage  

PubMed Central

In this paper we review the parameters that define the ECT electrical stimulus and discuss their biophysical roles. We also present the summary metrics of charge and energy that are conventionally used to describe the dose of ECT and the rules commonly deployed to individualize the dose for each patient. We then highlight the limitations of these summary metrics and dosing rules in that they do not adequately capture the roles of the distinct stimulus parameters. Specifically, there is strong theoretical and empirical evidence that stimulus parameters (pulse amplitude, shape, and width, and train frequency, directionality, polarity, and duration) exert unique neurobiological effects that are important for understanding ECT outcomes. Consideration of the distinct stimulus parameters, in conjunction with electrode placement, is central to further optimization of ECT dosing paradigms to improve the risk/benefit ratio. Indeed, manipulation of specific parameters, such as reduction of pulse width and increase in number of pulses, has already resulted in dramatic reduction of adverse side effects, while maintaining efficacy. Furthermore, the manipulation of other parameters, such as current amplitude, which are commonly held at fixed, high values, might be productively examined as additional means of targeting and individualizing the stimulus, potentially reducing side effects. We recommend that ECT dose be defined using all stimulus parameters rather than a summary metric. All stimulus parameters should be noted in treatment records and published reports. To enable research on optimization of dosing paradigms, we suggest that ECT devices provide capabilities to adjust and display all stimulus parameters. PMID:20805726

Peterchev, Angel V.; Rosa, Moacyr A.; Deng, Zhi-De; Prudic, Joan; Lisanby, Sarah. H.

2010-01-01

26

Nanomaterials and synergistic low intensity direct current (LIDC) stimulation technology for orthopaedic implantable medical devices  

PubMed Central

Nanomaterials play a significant role in biomedical research and applications due to their unique biological, mechanical, and electrical properties. In recent years, they have been utilised to improve the functionality and reliability of a wide range of implantable medical devices ranging from well-established orthopaedic residual hardware devices (e.g. hip implants) that can repair defects in skeletal systems to emerging tissue engineering scaffolds that can repair or replace organ functions. This review summarizes the applications and efficacies of these nanomaterials that include synthetic or naturally occurring metals, polymers, ceramics, and composites in orthopaedic implants, the largest market segment of implantable medical devices. The importance of synergistic engineering techniques that can augment or enhance the performance of nanomaterial applications in orthopaedic implants is also discussed,, the focus being on a low intensity direct electric current (LIDC) stimulation technology to promote the long-term antibacterial efficacy of oligodynamic metal-based surfaces by ionization, while potentially accelerating tissue growth and osseointegration. While many nanomaterials have clearly demonstrated their ability to provide more effective implantable medical surfaces, further decisive investigations are necessary before they can translate into medically safe and commercially viable clinical applications. The paper concludes with a discussion about some of the critical impending issues with the application of nanomaterials-based technologies in implantable medical devices, and potential directions to address these. PMID:23335493

Samberg, Meghan E.; Cohen, Paul H.; Wysk, Richard A.; Monteiro-Riviere, Nancy A.

2012-01-01

27

Ultra-low energy ion implantation technology using decaborane (B10H14)  

NASA Astrophysics Data System (ADS)

We have developed the first ever low-energy, high-dosage boron ion implantation technology using a decaborane (B10H14) molecule. Since B10H14 consists of ten boron atoms, they are implanted with about a one-tenth lower effective acceleration energy and a ten times higher effective beam current compared with those of boron. Using this implantation, we show an ultra-shallow 500 eV boron profile, which do not show transient diffusion after rapid thermal annealing.

Goto, K.; Matsuo, J.; Takeuchi, D.; Sugii, T.; Yamada, I.

1997-02-01

28

Decaborane (B10H14) ion implantation technology for sub-0.1-?m PMOSFET's  

Microsoft Academic Search

A low-energy, high-dosage boron ion implantation technology using a decaborane (B10H14) molecule is developed. Since B10N14 consists of ten boron atoms, they are implanted with about a one-tenth lower effective acceleration energy and ten times higher effective beam current compared with those of boron. We demonstrated an ultrashallow boron profile with 0.5 keV effective acceleration energy, which does not cause

K. Goto; J. Matsuo; Y. Tada; T. Sugii; I. Yamada

1999-01-01

29

Human implantation: the last barrier in assisted reproduction technologies?  

PubMed

Implantation processes are highly complex involving the actions of numerous hormones, immunoglobulins, cytokines and other factors in the endometrium. They are also essential matters for the success of assisted reproduction. The nature of early embryonic development is of equal significance. It involves ovarian follicle growth, ovulation, fertilization and preimplantation growth. These processes are affected by imbalanced chromosomal constitutions or slow developmental periods. Post-implantation death is also a significant factor in cases of placental insufficiency or recurrent abortion. Clearly, many of these matters can significantly affect birth rates. This review is concerned primarily with the oocyte, the early embryo and its chromosomal anomalies, and the nature of factors involved in implantation. These are clearly among the most important features in determining successful embryonic and fetal growth. Successive sections cover the endocrine stimulation of follicle growth in mice and humans, growth of human embryos in vitro, their apposition and attachment to the uterus, factors involved in embryo attachment to uterine epithelium and later stages of implantation, and understanding the gene control of polarities and other aspects of preimplantation embryo differentiation. New aspects of knowledge include the use of human oocyte maturation in vitro as an approach to simpler forms of IVF, and new concepts in developmental genetics. PMID:17169215

Edwards, Robert G

2006-12-01

30

Human implantation: the last barrier in assisted reproduction technologies?  

PubMed

Implantation processes are highly complex involving the actions of numerous hormones, immunoglobulins, cytokines and other factors in the endometrium. They are also essential matters for the success of assisted reproduction. The nature of early embryonic development is of equal significance. It involves ovarian follicle growth, ovulation, fertilization and preimplantation growth. These processes are affected by imbalanced chromosomal constitutions or slow developmental periods. Post-implantation death is also a significant factor in cases of placental insufficiency or recurrent abortion. Clearly, many of these matters can significantly affect birth rates. This review is concerned primarily with the oocyte, the early embryo and its chromosomal anomalies, and the nature of factors involved in implantation. These are clearly among the most important features in determining successful embryonic and fetal growth. Successive sections cover the endocrine stimulation of follicle growth in mice and humans, growth of human embryos in vitro, their apposition and attachment to the uterus, factors involved in embryo attachment to uterine epithelium and later stages of implantation, and understanding the gene control of polarities and other aspects of preimplantation embryo differentiation. New aspects of knowledge include the use of human oocyte maturation in vitro as an approach to simpler forms of IVF, and new concepts in developmental genetics. PMID:20483395

Edwards, Robert G

2007-01-01

31

Technological, biological, and acoustical constraints to music perception in cochlear implant users.  

PubMed

Despite advances in technology, the ability to perceive music remains limited for many cochlear implant users. This paper reviews the technological, biological, and acoustical constraints that make music an especially challenging stimulus for cochlear implant users, while highlighting recent research efforts to overcome these shortcomings. The limitations of cochlear implant devices, which have been optimized for speech comprehension, become evident when applied to music, particularly with regards to inadequate spectral, fine-temporal, and dynamic range representation. Beyond the impoverished information transmitted by the device itself, both peripheral and central auditory nervous system deficits are seen in the presence of sensorineural hearing loss, such as auditory nerve degeneration and abnormal auditory cortex activation. These technological and biological constraints to effective music perception are further compounded by the complexity of the acoustical features of music itself that require the perceptual integration of varying rhythmic, melodic, harmonic, and timbral elements of sound. Cochlear implant users not only have difficulty perceiving spectral components individually (leading to fundamental disruptions in perception of pitch, melody, and harmony) but also display deficits with higher perceptual integration tasks required for music perception, such as auditory stream segregation. Despite these current limitations, focused musical training programs, new assessment methods, and improvements in the representation and transmission of the complex acoustical features of music through technological innovation offer the potential for significant advancements in cochlear implant-mediated music perception. PMID:23665130

Limb, Charles J; Roy, Alexis T

2014-02-01

32

Evolution and acceptability of medical applications of RFID implants among early users of technology.  

PubMed

RFID as a wireless identification technology that may be combined with microchip implants have tremendous potential in today's market. Although these implants have their advantages and disadvantages, recent improvements how allowed for implants designed for humans. Focus was given to the use of RFID tags and its effects on technology and CRM through a case study on VeriChip, the only corporation to hold the rights and the patent to the implantable chip for humans, and an empirically based study on working professionals to measure perceptions by early adopters of such technology. Through hypotheses-testing procedures, it was found that although some resistance to accept microchip implants was found in several applications, especially among gender, it was totally expected that healthcare and medical record keeping activities would be universally treated in a positive light and the use of authorities (namely governmental agencies) would be equally treated in a negative light by both sexes. Future trends and recommendations are presented along with statistical results collected through personal interviews. PMID:19042524

Smith, Alan D

2007-01-01

33

Cochlear Implants  

MedlinePLUS

... are better able to hear, comprehend sound and music, and speak than their peers who receive implants ... future hold for cochlear implants? With advancements in technology and continued follow-up studies with people who ...

34

Implantable sensor technology: measuring bone and joint biomechanics of daily life in vivo  

PubMed Central

Stresses and strains are major factors influencing growth, remodeling and repair of musculoskeletal tissues. Therefore, knowledge of forces and deformation within bones and joints is critical to gain insight into the complex behavior of these tissues during development, aging, and response to injury and disease. Sensors have been used in vivo to measure strains in bone, intraarticular cartilage contact pressures, and forces in the spine, shoulder, hip, and knee. Implantable sensors have a high impact on several clinical applications, including fracture fixation, spine fixation, and joint arthroplasty. This review summarizes the developments in strain-measurement-based implantable sensor technology for musculoskeletal research. PMID:23369655

2013-01-01

35

Status of p-on- n Arsenic-Implanted HgCdTe Technologies  

NASA Astrophysics Data System (ADS)

In this paper recent developments made by the French Atomic Energies and Alternative Energies Commission (CEA) at the Electronics and Information Technology Laboratory (LETI) on the fabrication of planar p-on- n HgCdTe photodiodes are reported. Results obtained on long-wavelength infrared (LWIR) liquid-phase epitaxy (LPE) and mid- and short-wavelength infrared (MWIR/SWIR) molecular beam epitaxy (MBE) have been previously published. For these photodiodes, p-type doping is obtained by arsenic implantation followed by diffusion and activation under Hg-overpressure annealing. The active layer is n-type doped by indium incorporation during growth. Control of the p-on- n junctions is one of the key points of this technology, requiring good knowledge of the arsenic implantation and diffusion and the evolution of implantation-induced defects. Concerning implantation, the impact of dose (from 2 × 1014 at./cm2 to 2 × 1015 at./cm2) and energy (from 50 keV to 500 keV) on As profiles is considered. The profiles after implantation are modeled using Pearson IV moments. Realistic descriptions of arsenic distributions are obtained, and the evolution of moments with implantation conditions is fitted. In addition, implantation damage is examined by transmission electron microscopy (TEM) and the evolution of defects is studied depending on implantation conditions and Hg-overpressure annealing. Previous results obtained on 30- ?m-pitch LPE LWIR and MBE MWIR/SWIR showed state-of-the-art detector performance. Since these first results, progress has been made to decrease the pixel pitch to 15 ?m and increase the focal-plane array (FPA) format. In this way, 640 × 512 LPE LWIR FPAs have been processed and characterized. In addition we report results obtained on our first p-on- n very long-wavelength infrared (VLWIR) photodiode fabricated at CEA-LETI with ? c = 13.35 ?m at 50 K. These latest results demonstrate the viability of our technology and materials.

Mollard, L.; Destefanis, G.; Bourgeois, G.; Ferron, A.; Baier, N.; Gravrand, O.; Barnes, J. P.; Papon, A. M.; Milesi, F.; Kerlain, A.; Rubaldo, L.

2011-08-01

36

Cryogenic ion implantation near amorphization threshold dose for halo/extension junction improvement in sub-30 nm device technologies  

SciTech Connect

We report on junction advantages of cryogenic ion implantation with medium current implanters. We propose a methodical approach on maximizing cryogenic effects on junction characteristics near the amorphization threshold doses that are typically used for halo implants for sub-30 nm technologies. BF{sub 2}{sup +} implant at a dose of 8 Multiplication-Sign 10{sup 13}cm{sup -2} does not amorphize silicon at room temperature. When implanted at -100 Degree-Sign C, it forms a 30 - 35 nm thick amorphous layer. The cryogenic BF{sub 2}{sup +} implant significantly reduces the depth of the boron distribution, both as-implanted and after anneals, which improves short channel rolloff characteristics. It also creates a shallower n{sup +}-p junction by steepening profiles of arsenic that is subsequently implanted in the surface region. We demonstrate effects of implant sequences, germanium preamorphization, indium and carbon co-implants for extension/halo process integration. When applied to sequences such as Ge+As+C+In+BF{sub 2}{sup +}, the cryogenic implants at -100 Degree-Sign C enable removal of Ge preamorphization, and form more active n{sup +}-p junctions and steeper B and In halo profiles than sequences at room temperature.

Park, Hugh; Todorov, Stan; Colombeau, Benjamin; Rodier, Dennis; Kouzminov, Dimitry; Zou Wei; Guo Baonian; Khasgiwale, Niranjan; Decker-Lucke, Kurt [Applied Materials, Varian Semiconductor Equipment, 35 Dory Road, Gloucester, Massachusetts 01930 (United States)

2012-11-06

37

A low-frequency versatile wireless power transfer technology for biomedical implants.  

PubMed

Implantable biomedical sensors and actuators are highly desired in modern medicine. In many cases, the implant's electrical power source profoundly determines its overall size and performance . The inductively coupled coil pair operating at the radio-frequency (RF) has been the primary method for wirelessly delivering electrical power to implants for the last three decades . Recent designs significantly improve the power delivery efficiency by optimizing the operating frequency, coil size and coil distance . However, RF radiation hazard and tissue absorption are the concerns in the RF wireless power transfer technology (RF-WPTT) , . Also, it requires an accurate impedance matching network that is sensitive to operating environments between the receiving coil and the load for efficient power delivery . In this paper, a novel low-frequency wireless power transfer technology (LF-WPTT) using rotating rare-earth permanent magnets is demonstrated. The LF-WPTT is able to deliver 2.967 W power at  ? 180 Hz to an 117.1 ? resistor over 1 cm distance with 50% overall efficiency. Because of the low operating frequency, RF radiation hazard and tissue absorption are largely avoided, and the power delivery efficiency from the receiving coil to the load is independent of the operating environment. Also, there is little power loss observed in the LF-WPTT when the receiving coil is enclosed by non-magnetic implant-grade stainless steel. PMID:23893211

Jiang, Hao; Zhang, Junmin; Lan, Di; Chao; Liou, Shyshenq; Shahnasser, Hamid; Fechter, Richard; Hirose, Shinjiro; Harrison, Michael; Roy, Shuvo

2013-08-01

38

A phone-assistive device based on Bluetooth technology for cochlear implant users.  

PubMed

Hearing-impaired people, and particularly hearing-aid and cochlear-implant users, often have difficulty communicating over the telephone. The intelligibility of telephone speech is considerably lower than the intelligibility of face-to-face speech. This is partly because of lack of visual cues, limited telephone bandwidth, and background noise. In addition, cellphones may cause interference with the hearing aid or cochlear implant. To address these problems that hearing-impaired people experience with telephones, this paper proposes a wireless phone adapter that can be used to route the audio signal directly to the hearing aid or cochlear implant processor. This adapter is based on Bluetooth technology. The favorable features of this new wireless technology make the adapter superior to traditional assistive listening devices. A hardware prototype was built and software programs were written to implement the headset profile in the Bluetooth specification. Three cochlear implant users were tested with the proposed phone-adapter and reported good speech quality. PMID:14518792

Qian, Haifeng; Loizou, Philipos C; Dorman, Michael F

2003-09-01

39

Plasma-based ion implantation and deposition: A review of physics,technology, and applications  

SciTech Connect

After pioneering work in the 1980s, plasma-based ion implantation (PBII) and plasma-based ion implantation and deposition (PBIID) can now be considered mature technologies for surface modification and thin film deposition. This review starts by looking at the historical development and recalling the basic ideas of PBII. Advantages and disadvantages are compared to conventional ion beam implantation and physical vapor deposition for PBII and PBIID, respectively, followed by a summary of the physics of sheath dynamics, plasma and pulse specifications, plasma diagnostics, and process modeling. The review moves on to technology considerations for plasma sources and process reactors. PBII surface modification and PBIID coatings are applied in a wide range of situations. They include the by-now traditional tribological applications of reducing wear and corrosion through the formation of hard, tough, smooth, low-friction and chemically inert phases and coatings, e.g. for engine components. PBII has become viable for the formation of shallow junctions and other applications in microelectronics. More recently, the rapidly growing field of biomaterial synthesis makes used of PBII&D to produce surgical implants, bio- and blood-compatible surfaces and coatings, etc. With limitations, also non-conducting materials such as plastic sheets can be treated. The major interest in PBII processing originates from its flexibility in ion energy (from a few eV up to about 100 keV), and the capability to efficiently treat, or deposit on, large areas, and (within limits) to process non-flat, three-dimensional workpieces, including forming and modifying metastable phases and nanostructures. We use the acronym PBII&D when referring to both implantation and deposition, while PBIID implies that deposition is part of the process.

Pelletier, Jacques; Anders, Andre

2005-05-16

40

Ion beam technology applications study. [ion impact, implantation, and surface finishing  

NASA Technical Reports Server (NTRS)

Specific perceptions and possible ion beam technology applications were obtained as a result of a literature search and contact interviews with various institutions and individuals which took place over a 5-month period. The use of broad beam electron bombardment ion sources is assessed for materials deposition, removal, and alteration. Special techniques examined include: (1) cleaning, cutting, and texturing for surface treatment; (2) crosslinking of polymers, stress relief in deposited layers, and the creation of defect states in crystalline material by ion impact; and (3) ion implantation during epitaxial growth and the deposition of neutral materials sputtered by the ion beam. The aspects, advantages, and disadvantages of ion beam technology and the competitive role of alternative technologies are discussed.

Sellen, J. M., Jr.; Zafran, S.; Komatsu, G. K.

1978-01-01

41

Managing complexity: An integration of ethics, management, and technology viewed through the Dow Corning silicone implant case  

Microsoft Academic Search

This dissertation is a contextual examination of an ethical organizational dilemma complicated by elaborate and interrelated systems or soft technologies. Dow Corning's silicone breast implant case is analyzed by example, to show the usefulness of a more varied, flexible, and multi-faceted approach to ethics and management in the midst of a rapidly expanding technological society. This case represents an ongoing

Patricia Jane Tod

1999-01-01

42

Technology Advances and Challenges in Hermetic Packaging for Implantable Medical Devices  

Microsoft Academic Search

\\u000a Many implantable medical devices contain sophisticated electronic circuits. Hermetic packaging is required to provide the\\u000a implant’s electronic circuitry with protection from the harsh environment of the human body. This chapter provides a review\\u000a of available hermetic sealing methods and their applications. General considerations of implantable medical device packaging\\u000a are discussed. Various testing methods applicable to the packaging of implantable medical

Guangqiang Jiang; David D. Zhou

2010-01-01

43

The use of CAD/CAM technology to fabricate a custom ceramic implant abutment: a clinical report.  

PubMed

Well-placed dental implants are a prerequisite of functional and esthetically successful dental implant-supported crowns. The presence of soft tissue is essential for excellent esthetics because the dental implant or titanium abutment may become visible if the soft-tissue contour is not acceptable. This clinical report describes the use of a custom ceramic implant abutment designed with computer-aided design and computer-aided manufacturing (CAD/CAM) technology by milling a zirconia framework that was cemented extraorally to a prefabricated titanium abutment with a reduced diameter. This ceramic abutment has the strength and precise fit of a titanium interface and also the esthetic advantages of shaded custom-milled zirconia, with no visible metal. PMID:24433839

Bertolini, Martinna de Mendonça e; Kempen, Juan; Lourenço, Eduardo José Veras; Telles, Daniel de Moraes

2014-05-01

44

Design of a miniature implantable left ventricular assist device using CAD/CAM technology.  

PubMed

In this study, we developed a new miniature motor-driven pulsatile left ventricular assist device (LVAD) for implantation into a Japanese patient of average build by means of computer-aided design and manufacturing (CAD/CAM) technology. A specially designed miniature ball-screw and a high-performance brushless DC motor were used in an artificial heart actuator to allow miniaturization. A blood pump chamber (stroke volume 55 ml) and an inflow and outflow port were designed by computational fluid dynamics (CFD) analysis. The geometry of the blood pump was evaluated using the value of index of pump geometry (IPG) = (Reynolds shear stress) x (occupied volume) as a quantitative index for optimization. The calculated value of IPG varied from 20.6 Nm to 49.1 Nm, depending on small variations in pump geometry. We determined the optimum pump geometry based on the results of quantitative evaluation using IPG and qualitative evaluation using the flow velocity distribution with blood flow tracking. The geometry of the blood pump that gave lower shear stress had more optimum spiral flow around the diaphragm-housing (D-H) junction. The volume and weight of the new LVAD, made of epoxy resin, is 309 ml and 378 g, but further miniaturization will be possible by improving the geometry of both the blood pump and the back casing. Our results show that our new design method for an implantable LVAD using CAD/CAM promises to improve blood compatibility with greater miniaturization. PMID:14598098

Okamoto, Eiji; Hashimoto, Takuya; Mitamura, Yoshinori

2003-01-01

45

ECT AND PLATELET 5HT UPTAKE IN MAJOR DEPRESSION  

PubMed Central

Several studies have reported decreased platelet 5-HT uptake in patients of major depression. The mechanism of antidepressant action of ECT is not clear. The present work was undertaken with the aim to study the active platelet 5-HT uptake and the effect of ECT on it in patients of major depression. 15 patients of major depression (DSM-lll-R) and equal number of age and sex-matched controls were included in the study. Active platelet 5-HT uptake was determined before ECT, after a course of ECT and 7 days after last ECT. Platelet 5-HT uptake was. significantly lower in der essives than normal controls. After ECT treatment there was significant increase in 5-HT uptake which came down to pretreatment level after 1 week of last ECT. The effect of ECT on serotonergic system is discussed. PMID:21584091

Dalal, P.K.; Lal, Narottam; Trivedi, J.K.; Seth, P.K.; Agarwal, A.K.; Khalid, Abdul

1997-01-01

46

Simultaneous e ects of homogenization and vanishing viscosity  

E-print Network

Simultaneous e#11;ects of homogenization and vanishing viscosity in fully nonlinear elliptic simultaneous e#11;ects of homogenization and vanishing viscosity in uniformly and degenerate elliptic partial possible cases. Key Words: Homogenization, vanishing viscosity, elliptic equations, viscosity solu- tions

Ishii, Hitoshi

47

FIRST SEMESTER (27.5 ECTS) Cultural History of Tourism 3  

E-print Network

2 FIRST SEMESTER (27.5 ECTS) Cultural History of Tourism 3 Economics and Politics of International Tourism 4.5 E-tourism Technology Labs 3 International Relations and Tourism 3 New Media for Tourism Communication 4.5 Research Methods in Tourism 3 Rhetoric and Persuasion in Tourism Communication 3 Tourism

Krause, Rolf

48

Plasma-based ion implantation: a valuable technology for the elaboration of innovative materials and nanostructured thin films  

NASA Astrophysics Data System (ADS)

Plasma-based ion implantation (PBII), invented in 1987, can now be considered as a mature technology for thin film modification. After a brief recapitulation of the principle and physics of PBII, its advantages and disadvantages, as compared to conventional ion beam implantation, are listed and discussed. The elaboration of thin films and the modification of their functional properties by PBII have already been achieved in many fields, such as microelectronics (plasma doping/PLAD), biomaterials (surgical implants, bio- and blood-compatible materials), plastics (grafting, surface adhesion) and metallurgy (hard coatings, tribology), to name a few. The major advantages of PBII processing lie, on the one hand, in its flexibility in terms of ion implantation energy (from 0 to 100 keV) and operating conditions (plasma density, collisional or non-collisional ion sheath), and, on the other hand, in the easy transferrability of processes from the laboratory to industry. The possibility of modifying the composition and physical nature of the films, or of drastically changing their physical properties over several orders of magnitude makes this technology very attractive for the elaboration of innovative materials, including metastable materials, and the realization of micro- or nanostructures. A review of the state of the art in these domains is presented and illustrated through a few selected examples. The perspectives opened up by PBII processing, as well as its limitations, are discussed.

Vempaire, D.; Pelletier, J.; Lacoste, A.; Béchu, S.; Sirou, J.; Miraglia, S.; Fruchart, D.

2005-05-01

49

Rationale for the Use of CAD/CAM Technology in Implant Prosthodontics  

PubMed Central

Despite the predictable longevity of implant prosthesis, there is an ongoing interest to continue to improve implant prosthodontic treatment and outcomes. One of the developments is the application of computer-aided design and computer-aided manufacturing (CAD/CAM) to produce implant abutments and frameworks from metal or ceramic materials. The aim of this narrative review is to critically evaluate the rationale of CAD/CAM utilization for implant prosthodontics. To date, CAD/CAM allows simplified production of precise and durable implant components. The precision of fit has been proven in several laboratory experiments and has been attributed to the design of implants. Milling also facilitates component fabrication from durable and aesthetic materials. With further development, it is expected that the CAD/CAM protocol will be further simplified. Although compelling clinical evidence supporting the superiority of CAD/CAM implant restorations is still lacking, it is envisioned that CAD/CAM may become the main stream for implant component fabrication. PMID:23690778

Abduo, Jaafar; Lyons, Karl

2013-01-01

50

Submicron CBiCMOS technology with new well and buried layer formed by multiple energy ion implantation  

Microsoft Academic Search

A simple 0.6-?m complementary BiCMOS (CBiCMOS) technology was developed without an epitaxial layer. The wells and the buried layers for all transistors were formed by only three steps of masking layers, using multiple energy ion implantation with megaelectronvolt energy. The problem of the secondary defect induced by high dose and high energy ion implementation was solved by using the rapid

Keiichi HIGASHITANI; Takashi KUROI; K. Suda; M. Hatanaka; S. Nagao; N. Tsubouchi

1991-01-01

51

A 3.5GHz Power Amplifier Module Using Directly-Ion-Implanted GaAs MESFET Technology for Wireless Communications  

Microsoft Academic Search

GaAs power amplifier modules are the main components in the transmitter of a wireless com- munication system.High-performance GaAs power transistors play an important role for design of advanced GaAs power amplifier modules.The ion implantation technologies including selective and direct implantation approaches have the advantages of high uniformity, high throughput, and low costs over the epitaxial technologies for fabrication of microwave

Y.-L. Lai; D.-G. Liu; M.-S. Shiau; S.-Y. Yang

2000-01-01

52

Cochlear implants.  

PubMed

Cochlear implants are the first example of a neural prosthesis that can substitute a sensory organ: they bypass the malfunctioning auditory periphery of profoundly-deaf people to electrically stimulate their auditory nerve. The history of cochlear implants dates back to 1957, when Djourno and Eyriès managed, for the first time, to elicit sound sensations in a deaf listener using an electrode implanted in his inner ear. Since then, considerable technological and scientific advances have been made. Worldwide, more than 300,000 deaf people have been fitted with a cochlear implant; it has become a standard clinical procedure for born-deaf children and its success has led over the years to relaxed patient selection criteria; for example, it is now not uncommon to see people with significant residual hearing undergoing implantation. Although the ability to make sense of sounds varies widely among the implanted population, many cochlear implant listeners can use the telephone and follow auditory-only conversations in quiet environments. PMID:25247367

Macherey, Olivier; Carlyon, Robert P

2014-09-22

53

Polymeric heart valves for surgical implantation, catheter-based technologies and heart assist devices.  

PubMed

Efficient function and long-term durability without the need for anticoagulation, coupled with the ability to be accommodated in many different types of patient, are the principal requirements of replacement heart valves. Although the clinical use of valves appeared to have remained steady for several decades, the evolving demands for the elderly and frail patients typically encountered in the developed world, and the needs of much younger and poorer rheumatic heart disease patients in the developing world have now necessitated new paradigms for heart valve technologies and associated materials. This includes further consideration of durable elastomeric materials. The use of polymers to produce flexible leaflet valves that have the benefits of current commercial bioprosthetic and mechanical valves without any of their deficiencies has been held desirable since the mid 1950s. Much attention has been focused on thermoplastic polyurethanes in view of their generally good physico-chemical properties and versatility in processing, coupled with the improving biocompatibility and stability of recent formulations. Accelerated in vitro durability of between 600 and 1000 million cycles has been achieved using polycarbonate urethanes, and good resistance to degradation, calcification and thrombosis in vivo has been shown with some polysiloxane-based polyurethanes. Nevertheless, polymeric valves have remained relegated to use in temporary ventricular assist devices for bridging heart failure patients to transplantation. Some recent studies suggest that there is a greater degree of instability in thermoplastic materials than hitherto believed so that significant challenges remain in the search for the combination of durability and biocompatibility that would allow polymeric valves to become a clinical reality for surgical implantation. Perhaps more importantly, they could become candidates for use in situations where minimally invasive transcatheter procedures are used to replace diseased valves. Being amenable to relatively inexpensive mass production techniques, the attainment of this goal could benefit very large numbers of patients in developing and emerging countries who currently have no access to treatment for rheumatic heart disease that is so prevalent in these areas. This review discusses the evolution and current status of polymeric valves in wide-ranging circumstances. PMID:25443788

Bezuidenhout, Deon; Williams, David F; Zilla, Peter

2015-01-01

54

Biocorrosion of magnesium alloys: a new principle in cardiovascular implant technology?  

PubMed Central

Objectives: To develop and test a new concept of the degradation kinetics of newly developed coronary stents consisting of magnesium alloys. Methods: Design of a coronary stent prototype consisting of the non-commercial magnesium based alloy AE21 (containing 2% aluminium and 1% rare earths) with an expected 50% loss of mass within six months. Eleven domestic pigs underwent coronary implantation of 20 stents (overstretch injury). Results: No stent caused major problems during implantation or showed signs of initial breakage in the histological evaluation. There were no thromboembolic events. Quantitative angiography at follow up showed a significant (p < 0.01) 40% loss of perfused lumen diameter between days 10 and 35, corresponding to neointima formation seen on histological analysis, and a 25% re-enlargement (p < 0.05) between days 35 and 56 caused by vascular remodelling (based on intravascular ultrasound) resulting from the loss of mechanical integrity of the stent. Inflammation (p < 0.001) and neointimal plaque area (p < 0.05) depended significantly on injury score. Planimetric degradation correlated with time (r = 0.67, p < 0.01). Conclusion: Vascular implants consisting of magnesium alloy degradable by biocorrosion seem to be a realistic alternative to permanent implants. PMID:12748224

Heublein, B; Rohde, R; Kaese, V; Niemeyer, M; Hartung, W; Haverich, A

2003-01-01

55

Design and simulation of an implantable medical drug delivery system using microelectromechanical systems technology  

Microsoft Academic Search

A unique design of an implantable micropump for medical drug delivery systems was proposed. The peristaltic pumping principle was selected. Three pump chambers are individually actuated by each bulk PZT (lead zirconate titanate) disk in a peristaltic motion. It is this peristaltic motion that propels the fluid. The design of the micropump includes inlet, three pump chambers, three silicon membranes,

Li Cao; Susan Mantell; Dennis Polla

2001-01-01

56

Acute bilateral ECT in a depressed patient with a hip-aztreonam-spacer and subsequent maintenance ECT after prosthesis collocation.  

PubMed

ABSTRACT Electroconvulsive Therapy (ECT) has been demonstrated to be a safe and effective treatment for geriatric depression, although its application might be challenging when medical comorbidities exist. The present case reports a 78-year-old man diagnosed with recurrent unipolar major depressive disorder (MDD), who presented with a severe depressive episode with psychotic features (DSM IV). He successfully received a course of bitemporal (BT) ECT with a hip-aztreonam-spacer due to a hip fracture that occurred during hospitalization. This was followed by maintenance ECT (M-ECT) with a recent prosthesis collocation. This particular case illustrates the importance of a multidisciplinary approach in geriatric patients with somatic complications receiving ECT. PMID:25381759

Gálvez, Verònica; de Arriba Arnau, Aida; Martínez-Amorós, Erika; Ribes, Carmina; Urretavizcaya, Mikel; Cardoner, Narcís

2014-11-10

57

Development of a "Self-Cleaning" Encapsulation Technology for Implantable Glucose Monitoring  

E-print Network

........................................... 97 6.2 Optical properties of skin model layers ...................................................... 101 6.3 Physical properties of common contraceptive implants ............................. 104 6.4 Classification of medical devices... is 140 to 199 mg/dL after a 2 hour oral glucose tolerance test.4 The growing epidemic is so 4 serious that it prompted a United Nations Resolution on diabetes, which designates November 14th as World Diabetes Day in order to raise public awareness...

Gant, Rebecca M.

2011-02-22

58

Surface modification of titanium implants using bioactive glasses with air abrasion technologies  

Microsoft Academic Search

A growing number of surface treated titanium implants are routinely used in dental and orthopaedic surgery, with a view to\\u000a enhancing integration capacity with osseous tissue. This study examines the use of bioactive glass 45S5 as an alternative\\u000a abrasive and osteoproductive surface modification material. Abrasive blasting of commercially pure titanium with bioactive\\u000a glass 45S5 produced an irregular finish with a

Garrit Koller; Richard J. Cook; Ian D. Thompson; Timothy F. Watson; Lucy Di Silvio

2007-01-01

59

Packaging and Non-Hermetic Encapsulation Technology for Flip Chip on Implantable MEMS Devices  

PubMed Central

We report here a successful demonstration of a flip-chip packaging approach for a microelectromechanical systems (MEMS) device with in-plane movable microelectrodes implanted in a rodent brain. The flip-chip processes were carried out using a custom-made apparatus that was capable of the following: 1) creating Ag epoxy microbumps for first-level interconnect; 2) aligning the die and the glass substrate; and 3) creating non-hermetic encapsulation (NHE). The completed flip-chip package had an assembled weight of only 0.5 g significantly less than the previously designed wire-bonded package of 4.5 g. The resistance of the Ag bumps was found to be negligible. The MEMS micro-electrodes were successfully tested for its mechanical movement with microactuators generating forces of 450 ?N with a displacement resolution of 8.8 ?m/step. An NHE on the front edge of the package was created by patterns of hydrophobic silicone microstructures to prevent contamination from cerebrospinal fluid while simultaneously allowing the microelectrodes to move in and out of the package boundary. The breakdown pressure of the NHE was found to be 80 cm of water, which is significantly (4.5–11 times) larger than normal human intracranial pressures. Bench top tests and in vivo tests of the MEMS flip-chip packages for up to 75 days showed reliable NHE for potential long-term implantation. PMID:24431925

Sutanto, Jemmy; Anand, Sindhu; Sridharan, Arati; Korb, Robert; Zhou, Li; Baker, Michael S.; Okandan, Murat; Muthuswamy, Jit

2013-01-01

60

Packaging and Non-Hermetic Encapsulation Technology for Flip Chip on Implantable MEMS Devices.  

PubMed

We report here a successful demonstration of a flip-chip packaging approach for a microelectromechanical systems (MEMS) device with in-plane movable microelectrodes implanted in a rodent brain. The flip-chip processes were carried out using a custom-made apparatus that was capable of the following: 1) creating Ag epoxy microbumps for first-level interconnect; 2) aligning the die and the glass substrate; and 3) creating non-hermetic encapsulation (NHE). The completed flip-chip package had an assembled weight of only 0.5 g significantly less than the previously designed wire-bonded package of 4.5 g. The resistance of the Ag bumps was found to be negligible. The MEMS micro-electrodes were successfully tested for its mechanical movement with microactuators generating forces of 450 ?N with a displacement resolution of 8.8 ?m/step. An NHE on the front edge of the package was created by patterns of hydrophobic silicone microstructures to prevent contamination from cerebrospinal fluid while simultaneously allowing the microelectrodes to move in and out of the package boundary. The breakdown pressure of the NHE was found to be 80 cm of water, which is significantly (4.5-11 times) larger than normal human intracranial pressures. Bench top tests and in vivo tests of the MEMS flip-chip packages for up to 75 days showed reliable NHE for potential long-term implantation. PMID:24431925

Sutanto, Jemmy; Anand, Sindhu; Sridharan, Arati; Korb, Robert; Zhou, Li; Baker, Michael S; Okandan, Murat; Muthuswamy, Jit

2012-04-10

61

Design of high-speed ECT and ERT system  

NASA Astrophysics Data System (ADS)

Process tomography technique provides a novel method to investigate the multi-phase flow distribution inside pipe or vessel. Electrical resistance tomography (ERT) and electrical capacitance tomography (ECT) are extensively studied in recent years. As the capacitance to voltage and resistance to voltage converters run faster, the speeds of other circuits in the system, such as MCU, A/D, D/A etc, have become the bottlenecks of improving the speed. This paper describes a new dual-modal, ECT and ERT, data acquisition system. The system is controlled by a digital signal processor. Both the ERT and the ECT systems use one platform to simplify the system design and maintenance. The system can work at high speed which is only limited by the capacitance to voltage converter or resistance to voltage converter. Primary test results show the speed of the new system is 1400 frames/second for 16-electrode ERT and 2200 frames/second for 12-electrode ECT.

Wang, Baoliang; Huang, Zhiyao; Li, Haiqing

2009-02-01

62

Zirconia dental implants: a literature review.  

PubMed

Titanium and titanium alloys are widely used for fabrication of dental implants. Because of potential immunologic and possible esthetic compromises with titanium implants, novel implant technologies are being developed. However, these novel technologies must maintain the characteristics that provide titanium implants with their high success rates. Zirconia implants were introduced into dental implantology as an alternative to titanium implants. Zirconia seems to be a suitable implant material because of its toothlike color, mechanical properties, biocompatibility, and low plaque affinity. The aim of this study is to review clinical and research articles conducted on zirconia dental implants, compare them with titanium dental implants, and provide information on zirconia dental implant osseointegration and mechanical strength. Zirconia dental implants have the potential to become alternative dental implants to titanium dental implants, but they are not yet in routine clinical use. PMID:20545529

Özkurt, Zeynep; Kazazo?lu, Ender

2011-06-01

63

Cochlear Implants  

MedlinePLUS

... FDA) website on cochlear implants. Cochlear implants are electronic hearing devices. Doctors implant cochlear implants into people ... State & Local Officials Consumers Health Professionals Science & Research Industry Scroll back to top

64

Bifrontal ECT for drug-induced psychosis in Parkinson's disease.  

PubMed

Psychosis has been documented to occur during treatment for idiopathic Parkinson's disease (PD). This case report describes an elderly male who developed psychosis during the course of treatment for idiopathic PD. He was treated with clozapine but experienced significant adverse effects without clinical improvement. He was prescribed bifrontal electroconvulsive therapy (BF-ECT). Here, we report the efficacy of BF-ECT in treating psychosis and motor symptoms in PD, without producing cognitive side effects in an elderly male. PMID:21772651

Muralidharan, K; Thimmaiah, R; Chakraborty, V; Jain, S

2011-04-01

65

SERUM POTASSIUM CHANGES WITH E.C.T.  

PubMed Central

SUMMARY Serum potassium changes with direct E.C.T. and with modified E.C.T., given under three anaesthetic (thiopentone, diazepam and propanidid) and relaxant (suxamethonium) combinations were studied in 25 patients. Ten patients each, undergoing minor surgical procedures, acted as controls for these three combinations. Modified E.C.T. caused a rise in scram potassium, which, being highest at 3 minutes, was sustained well beyond 10 minutes. Direct E.C.T. caused maximum rise within one minute which, however, came down rapidly. The rise following modified E.C.T. was one and half times more compared to that occurring in controls given only drugs but not E.C.T., in all the three anaesthetic-relaxant combinations. The rise from pre-induction level was maximum following diazepam and minimum with propanidid, thiopentone falling in between. The rise from pre-relaxant level, on the other hand, was maximum with thiopentone and minimum with propanidid. PMID:21965907

Shukla, G.D.; Srivastava, S.L.; Kaur, A.; Varma, D.D.; Doshi, L.D.

1982-01-01

66

Results of 2007 Ect Benchmark Obtained with Civa at Cea: Prediction of Ect Inspection Over Tubes with 2d or 3d Flaws  

Microsoft Academic Search

The French Atomic Energy Commission (CEA) has developed for years the software CIVA dedicated to the simulation of NDT techniques such as Eddy Current Testing (ECT). ECT modeling is achieved in CIVA using semi-analytical models based on the Volume Integral Method (VIM). This paper presents results obtained with CIVA for the QNDE 2007 ECT benchmark, dedicated to the inspection of

G. Pichenot; C. Reboud; R. Raillon; S. Mahaut

2008-01-01

67

Miniature low-power inertial sensors: promising technology for implantable motion capture systems.  

PubMed

Inertial and magnetic sensors are valuable for untethered, self-contained human movement analysis. Very recently, complete integration of inertial sensors, magnetic sensors, and processing into single packages, has resulted in miniature, low power devices that could feasibly be employed in an implantable motion capture system. We developed a wearable sensor system based on a commercially available system-in-package inertial and magnetic sensor. We characterized the accuracy of the system in measuring 3-D orientation-with and without magnetometer-based heading compensation-relative to a research grade optical motion capture system. The root mean square error was less than 4° in dynamic and static conditions about all axes. Using four sensors, recording from seven degrees-of-freedom of the upper limb (shoulder, elbow, wrist) was demonstrated in one subject during reaching motions. Very high correlation and low error was found across all joints relative to the optical motion capture system. Findings were similar to previous publications using inertial sensors, but at a fraction of the power consumption and size of the sensors. Such ultra-small, low power sensors provide exciting new avenues for movement monitoring for various movement disorders, movement-based command interfaces for assistive devices, and implementation of kinematic feedback systems for assistive interventions like functional electrical stimulation. PMID:24846651

Lambrecht, Joris M; Kirsch, Robert F

2014-11-01

68

Engineering the heart: Evaluation of conductive nanomaterials for improving implant integration and cardiac function  

NASA Astrophysics Data System (ADS)

Recently, carbon nanotubes together with other types of conductive materials have been used to enhance the viability and function of cardiomyocytes in vitro. Here we demonstrated a paradigm to construct ECTs for cardiac repair using conductive nanomaterials. Single walled carbon nanotubes (SWNTs) were incorporated into gelatin hydrogel scaffolds to construct three-dimensional ECTs. We found that SWNTs could provide cellular microenvironment in vitro favorable for cardiac contraction and the expression of electrochemical associated proteins. Upon implantation into the infarct hearts in rats, ECTs structurally integrated with the host myocardium, with different types of cells observed to mutually invade into implants and host tissues. The functional measurements showed that SWNTs were essential to improve the performance of ECTs in inhibiting pathological deterioration of myocardium. This work suggested that conductive nanomaterials hold therapeutic potential in engineering cardiac tissues to repair myocardial infarction.

Zhou, Jin; Chen, Jun; Sun, Hongyu; Qiu, Xiaozhong; Mou, Yongchao; Liu, Zhiqiang; Zhao, Yuwei; Li, Xia; Han, Yao; Duan, Cuimi; Tang, Rongyu; Wang, Chunlan; Zhong, Wen; Liu, Jie; Luo, Ying; (Mengqiu) Xing, Malcolm; Wang, Changyong

2014-01-01

69

Status of p -on- n Arsenic-Implanted HgCdTe Technologies  

Microsoft Academic Search

In this paper recent developments made by the French Atomic Energies and Alternative Energies Commission (CEA) at the Electronics\\u000a and Information Technology Laboratory (LETI) on the fabrication of planar p-on-n HgCdTe photodiodes are reported. Results obtained on long-wavelength infrared (LWIR) liquid-phase epitaxy (LPE) and mid-\\u000a and short-wavelength infrared (MWIR\\/SWIR) molecular beam epitaxy (MBE) have been previously published. For these photodiodes,

L. Mollard; G. Destefanis; G. Bourgeois; A. Ferron; N. Baier; O. Gravrand; J. P. Barnes; A. M. Papon; F. Milesi; A. Kerlain; L. Rubaldo

2011-01-01

70

Implantation characteristics by boron cluster ion implantation  

NASA Astrophysics Data System (ADS)

Recently, boron cluster implantation (i.e. decaborane: B10Hx+) is regarded as a promising technology for the formation of P-type Ultra Shallow Junction (USJ) because of the equivalent high beam current with less beam divergence compared to the conventional B+ or BF2+ implantation. Also as-implanted and after-annealing characteristics are different due to the appearance of self-amorphized layer by the cluster ion bombardment, which suppresses the channeling and enhances the boron activation. However, it is anticipated that the properties caused by this amorphous layer will vary with different implantation conditions or a presence of Pre Amorphization Implantation (PAI) process, which should be understood well to maintain a good process control. From this point of view, we have measured the decaborane implantation characteristics by a couple of different related conditions, for instance, the beam energy and current. Sheet resistance vs junction depth (Rs-Xj) are also evaluated in different annealing methods with combination of PAI processes. In addition, a brief comparison is made by implanting the different boron cluster ions (i.e. B8Hx+) by mass selecting the ions extracted from decaborane ionization chamber. In this paper, these characteristics of boron cluster implantations are reviewed.

Nagayama, Tsutomu; Hamamoto, Nariaki; Umisedo, Sei; Tanjyo, Masayasu; Aoyama, Takayuki

2006-11-01

71

SEMICONDUCTOR TECHNOLOGY: Influence of nitrogen dose on the charge density of nitrogen-implanted buried oxide in SOI wafers  

NASA Astrophysics Data System (ADS)

To harden silicon-on-insulator (SOI) wafers fabricated using separation by implanted oxygen (SIMOX) to total-dose irradiation, the technique of nitrogen implantation into the buried oxide (BOX) layer of SIMOX wafers can be used. However, in this work, it has been found that all the nitrogen-implanted BOX layers reveal greater initial positive charge densities, which increased with increasing nitrogen implantation dose. Also, the results indicate that excessively large nitrogen implantation dose reduced the radiation tolerance of BOX for its high initial positive charge density. The bigger initial positive charge densities can be ascribed to the accumulation of implanted nitrogen near the Si-BOX interface after annealing. On the other hand, in our work, it has also been observed that, unlike nitrogen-implanted BOX, all the fluorine-implanted BOX layers show a negative charge density. To obtain the initial charge densities of the BOX layers, the tested samples were fabricated with a metal-BOX-silicon (MBS) structure based on SIMOX wafers for high-frequency capacitance-voltage (C-V) analysis.

Zhongshan, Zheng; Zhongli, Liu; Ning, Li; Guohua, Li; Enxia, Zhang

2010-02-01

72

Science and Technology of Bio-Inert Thin Films as Hermetic-Encapsulating Coatings for Implantable Biomedical Devices: Application to Implantable Microchip in the Eye for the Artificial Retina  

NASA Astrophysics Data System (ADS)

Extensive research has been devoted to the development of neuron prostheses and hybrid bionic systems to establish links between the nervous system and electronic or robotic prostheses with the main focus of restoring motor and sensory functions in blind patients. Artificial retinas, one type of neural prostheses we are currently working on, aim to restore some vision in blind patients caused by retinitis picmentosa or macular degeneration, and in the future to restore vision at the level of face recognition, if not more. Currently there is no hermetic microchip-size coating that provides a reliable, long-term (years) performance as encapsulating coating for the artificial retina Si microchip to be implanted inside the eye. This chapter focuses on the critical topics relevant to the development of a robust, long-term artificial retina device, namely the science and technology of hermetic bio-inert encapsulating coatings to protect a Si microchip implanted in the human eye from being attacked by chemicals existing in the eye's saline environment. The work discussed in this chapter is related to the development of a novel ultrananocrystalline diamond (UNCD) hermetic coating, which exhibited no degradation in rabbit eyes. The material synthesis, characterization, and electrochemical properties of these hermetic coatings are reviewed for application as encapsulating coating for the artificial retinal microchips implantable inside the human eye. Our work has shown that UNCD coatings may provide a reliable hermetic bio-inert coating technology for encapsulation of Si microchips implantable in the eye specifically and in the human body in general. Electrochemical tests of the UNCD films grown under CH4/Ar/H2 (1%) plasma exhibit the lowest leakage currents (˜7 × 10-7 A/cm2) in a saline solution simulating the eye environment. This leakage is incompatible with the functionality of the first-generation artificial retinal microchip. However, the growth of UNCD on top of the Si microchip passivated by a silicon nitride layer or the oxide layers is also under investigation in our group as introduced in this chapter. The electrochemically induced leakage will be reduced by at least one to three orders of magnitude to the range of 10-10 A/cm2, which is compatible with reliable, long-term implants.

Auciello, Orlando; Shi, Bing

73

Titel des Moduls: LP (nach ECTS): Kurzbezeichnung: Project Numerical Analysis  

E-print Network

Titel des Moduls: LP (nach ECTS): Kurzbezeichnung: Project Numerical Analysis 6 PNA Verantwortlich. Qualifikationsziele This is an advanced project course in Numerical Analysis. Students shall learn how to apply-Art SWS LP P / W / WP Semester Project Numerical Analysis IV 4 6 P WS/SS 5. Beschreibung der Lehrformen

Nabben, Reinhard

74

Optical absorption spectra and geometric e ects in higher fullerenes  

E-print Network

Optical absorption spectra and geometric e ects in higher fullerenes (Running head: Optical absorption in higher fullerenes) Kikuo Harigaya and Shuji Abe Physical Science Division, Electrotechnical of their amplitudes at the pentagons. The oscillator strengths of projected absorption almost accord with those

Harigaya, Kikuo

75

In ationary e!ect of crude oil prices in Turkey  

Microsoft Academic Search

It is generally acknowledged that changes in oil prices a!ect economic welfare in ways that are not entirely re ected in transactions in the oil market. In this article, by using the 1990 input- output table, the in ationary e!ects of crude oil prices are investigated for Turkey. Under 2xed nominal wages, pro2ts, interest and rent earnings, the e!ect of

Hakan Berument; Hakan Ta

76

Dental Implant Systems  

PubMed Central

Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with vital hard/soft tissue and is subjected to chemical as well as mechanical bio-environments. Such requirements should, at least, include biological compatibility, mechanical compatibility, and morphological compatibility to surrounding vital tissues. In this review, based on carefully selected about 500 published articles, these requirements plus MRI compatibility are firstly reviewed, followed by surface texturing methods in details. Normally dental implants are placed to lost tooth/teeth location(s) in adult patients whose skeleton and bony growth have already completed. However, there are some controversial issues for placing dental implants in growing patients. This point has been, in most of dental articles, overlooked. This review, therefore, throws a deliberate sight on this point. Concluding this review, we are proposing a novel implant system that integrates materials science and up-dated surface technology to improve dental implant systems exhibiting bio- and mechano-functionalities. PMID:20480036

Oshida, Yoshiki; Tuna, Elif B.; Aktören, Oya; Gençay, Koray

2010-01-01

77

Power supply's design and research for high voltage circuit of active ECT  

Microsoft Academic Search

Electronic Current Transformer (ECT) is an important equipment when constructing a major digital substation. The power supply of the ECT is intended solely for providing the DC power supply that could ensure the data collecting system's normal working. And which is the key way to ensure the reliability and accuracy of ECT. A new model of the power supply based

Zhang YiJie; Zeng Xiangjun; Liu Weibo; Zhao Zhenfeng; Li Jian

2010-01-01

78

Relating Operational and Denotational Semantics for Input/Output E ects  

E-print Network

Relating Operational and Denotational Semantics for Input/Output E ects Roy L. Crole Department side-e ects. Our vehicle is a small higher-order imperative language, with operations for interactive and denotational semantics for I/O e ects. We use a novel labelled transition system that uni- formly expresses

Crole, Roy L.

79

B 259---261 (1999) ---361 Localization e#ects disordered Kondo lattices  

E-print Network

Physica B 259---261 (1999) ---361 Localization e#ects disordered Kondo lattices Miranda lattices. that distribution Kondo temperatures strongly a#ected by fluctuations the conduction electron investigate role localization e#ects Kondo disorder mechanism non­Fermi liquid behavior disordered Kondo

Miranda, Eduardo

80

Current trends in dental implants  

PubMed Central

Tooth loss is very a very common problem; therefore, the use of dental implants is also a common practice. Although research on dental implant designs, materials and techniques has increased in the past few years and is expected to expand in the future, there is still a lot of work involved in the use of better biomaterials, implant design, surface modification and functionalization of surfaces to improve the long-term outcomes of the treatment. This paper provides a brief history and evolution of dental implants. It also describes the types of implants that have been developed, and the parameters that are presently used in the design of dental implants. Finally, it describes the trends that are employed to improve dental implant surfaces, and current technologies used for the analysis and design of the implants. PMID:24868501

Gaviria, Laura; Salcido, John Paul; Guda, Teja

2014-01-01

81

Results of 2007 Ect Benchmark Obtained with Civa at Cea: Prediction of Ect Inspection Over Tubes with 2d or 3d Flaws  

NASA Astrophysics Data System (ADS)

The French Atomic Energy Commission (CEA) has developed for years the software CIVA dedicated to the simulation of NDT techniques such as Eddy Current Testing (ECT). ECT modeling is achieved in CIVA using semi-analytical models based on the Volume Integral Method (VIM). This paper presents results obtained with CIVA for the QNDE 2007 ECT benchmark, dedicated to the inspection of tube affected by 2D and 3D flaws. Further configurations are also proposed for future benchmark sessions.

Pichenot, G.; Reboud, C.; Raillon, R.; Mahaut, S.

2008-02-01

82

Guided surgery for implant therapy.  

PubMed

New three-dimensional diagnostic and treatment planning technologies in implant dentistry have expanded on concepts of a team approach to the planning and placement of dental implants. The accurate and predictable placement of implants according to a computer-generated virtual treatment plan is now a reality, taking the virtual plan from the computer to the patient clinically. Recent advances in three-dimensional imaging in dentistry, in combination with the introduction of third-party proprietary implant planning software and associated surgical instrumentation, have revolutionized dental implant diagnosis and treatment and created an interdisciplinary environment in which communication leads to better patient care and outcomes. PMID:21492799

Orentlicher, Gary; Abboud, Marcus

2011-05-01

83

Thyratron modulators in plasma source ion implantation  

Microsoft Academic Search

Plasma source ion implantation (PSII) is an emerging technology which can be used to harden metal surfaces in a conformal manner. North Star Research Corp. (NSRC) is building a unique implanter system for Empire Hard Chrome which will be the first truly commercial implanter of this type. The choice of pulsed power technology for this application is important from the

R. J. Adler; J. Scheuer; W. Horne

1995-01-01

84

Low Energy Implantation for Medium Current Implanter with Molecular Ions  

NASA Astrophysics Data System (ADS)

Ion implantation is now indispensable process for semiconductor device fabrication. One of the key issues for the next generation LSI device fabrication is the formation of ultra shallow junction using Boron implantation. Medium current ion implanter for LSI production use can dope ions to the device wafer with accurately controlled uniformity and incident angle at a variety of energy ranges. However, the productivity of LSI at sub-keV energy region with conventional atomic B+ implantation will quickly fall down due to the low beam current caused by the well-known space charge limitation. To achieve a high productivity in this energy region, Decaborane (B10Hx+) implantation is supposed to be an appropriate solution. We are to review the technologies used for the commercial medium current ion implanter including Decaborane implantation for ultra shallow junction formation.

Nagai, Nobuo; Sakai, Shigeki; Hamamoto, Nariaki; Naito, Masao

2003-08-01

85

Design of high-speed ECT and ERT system  

Microsoft Academic Search

Process tomography technique provides a novel method to investigate the multi-phase flow distribution inside pipe or vessel. Electrical resistance tomography (ERT) and electrical capacitance tomography (ECT) are extensively studied in recent years. As the capacitance to voltage and resistance to voltage converters run faster, the speeds of other circuits in the system, such as MCU, A\\/D, D\\/A etc, have become

Baoliang Wang; Zhiyao Huang; Haiqing Li

2009-01-01

86

Volatility-Spillover E ?ects in European Bond Markets  

Microsoft Academic Search

We analyze volatility spillover from the US and aggregate European bond markets into individual European bond markets using a GARCH volatility-spillover model. We ?nd strong statistical evidence of volatility-spillover e ?ects from both the US and Europe into the individual bond markets.For the EMU countries,the US volatility-spillover effects are rather weak whereas the European volatility-spillover effects are strong.The opposite applies

Charlotte Christiansen

2003-01-01

87

Introduction to Special Issue on Implantable Electronics With great advances in electronics and electrode technologies, it has become possible  

E-print Network

as in Functional Electrical Stimulation (FES) to assist patients in grasping, standing, or urination. Deep brain broad scientific and transformational impact. They are saving or enhancing the lives of millions through systems in future. The next two articles describe implantable systems that interface with the brain

Bhunia, Swarup

88

Superelastic Orthopedic Implant Coatings  

NASA Astrophysics Data System (ADS)

The demand for hip and knee replacement surgery is substantial and growing. Unfortunately, most joint replacement surgeries will fail within 10-25 years, thereby requiring an arduous, painful, and expensive revision surgery. To address this issue, a novel orthopedic implant coating material ("eXalt") has been developed. eXalt is comprised of super elastic nitinol wire that is knit into a three-dimensional spacer fabric structure. eXalt expands in vivo to conform to the implantation site and is porous to allow for bone ingrowth. The safety and efficacy of eXalt were evaluated through structural analysis, mechanical testing, and a rabbit implantation model. The results demonstrate that eXalt meets or exceeds the performance of current coating technologies with reduced micromotion, improved osseointegration, and stronger implant fixation in vivo.

Fournier, Eric; Devaney, Robert; Palmer, Matthew; Kramer, Joshua; El Khaja, Ragheb; Fonte, Matthew

2014-07-01

89

Up-regulation of ECT2 is associated with poor prognosisn gastric cancer patients  

PubMed Central

Objectives: The aim of this study was to investigate the expression of ECT2 in gastric cancer and its clinical significance. Methods and results: We investigated the differentially expressed genes between gastric cancer tissues and normal gastric mucosa by cDNA microarray, and then we found ECT2 was up-regulated in gastric cancer. What is more, we verified ECT2 expression level by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and measured its protein level by immunohistochemistry (IHC). qRT-PCR analysis indicated ECT2 was significantly up-regulated in gastric cancer and Immunohistochemistry confirmed the percentage of ECT2-positive specimens was significantly higher in gastric carcinoma than in non-tumor tissues. Up-regulation of ECT2 is associated with the degree of histological differentiation (P = 0.007), invasion depth (P = 0.047), lymph node metastasis (P = 0.016), distant metastasis (P = 0.021) and TNM stage (P = 0.016), patients with up-regulated ECT2 had a lower overall survival rate (P = 0.000). Cox regression analysis revealed that up-regulation of ECT2 is an independent prognostic factor in gastric cancer patients (P = 0.012). Conclusion: Up-regulation of ECT2 might contribute to the progression of gastric carcinogenesis and may be a useful prognostic indicator in gastric cancer.

Jin, Yi; Yu, Yuhui; Shao, Qinshu; Ma, Yingyu; Zhang, Ruxuan; Yao, Haibo; Xu, Yuan

2014-01-01

90

Preconditioned alternating projection algorithms for maximum a posteriori ECT reconstruction  

NASA Astrophysics Data System (ADS)

We propose a preconditioned alternating projection algorithm (PAPA) for solving the maximum a posteriori (MAP) emission computed tomography (ECT) reconstruction problem. Specifically, we formulate the reconstruction problem as a constrained convex optimization problem with the total variation (TV) regularization. We then characterize the solution of the constrained convex optimization problem and show that it satisfies a system of fixed-point equations defined in terms of two proximity operators raised from the convex functions that define the TV-norm and the constraint involved in the problem. The characterization (of the solution) via the proximity operators that define two projection operators naturally leads to an alternating projection algorithm for finding the solution. For efficient numerical computation, we introduce to the alternating projection algorithm a preconditioning matrix (the EM-preconditioner) for the dense system matrix involved in the optimization problem. We prove theoretically convergence of the PAPA. In numerical experiments, performance of our algorithms, with an appropriately selected preconditioning matrix, is compared with performance of the conventional MAP expectation-maximization (MAP-EM) algorithm with TV regularizer (EM-TV) and that of the recently developed nested EM-TV algorithm for ECT reconstruction. Based on the numerical experiments performed in this work, we observe that the alternating projection algorithm with the EM-preconditioner outperforms significantly the EM-TV in all aspects including the convergence speed, the noise in the reconstructed images and the image quality. It also outperforms the nested EM-TV in the convergence speed while providing comparable image quality.

Krol, Andrzej; Li, Si; Shen, Lixin; Xu, Yuesheng

2012-11-01

91

Endodontic implants  

PubMed Central

Endodontic implants were introduced back in 1960. Endodontic implants enjoyed few successes and many failures. Various reasons for failures include improper case selection, improper use of materials and sealers and poor preparation for implants. Proper case selection had given remarkable long-term success. Two different cases are being presented here, which have been treated successfully with endodontic implants and mineral trioxide aggregate Fillapex (Andreaus, Brazil), an MTA based sealer. We suggest that carefully selected cases can give a higher success rate and this method should be considered as one of the treatment modalities. PMID:25298723

Yadav, Rakesh K.; Tikku, A. P.; Chandra, Anil; Wadhwani, K. K.; Ashutosh kr; Singh, Mayank

2014-01-01

92

Endodontic implants.  

PubMed

Endodontic implants were introduced back in 1960. Endodontic implants enjoyed few successes and many failures. Various reasons for failures include improper case selection, improper use of materials and sealers and poor preparation for implants. Proper case selection had given remarkable long-term success. Two different cases are being presented here, which have been treated successfully with endodontic implants and mineral trioxide aggregate Fillapex (Andreaus, Brazil), an MTA based sealer. We suggest that carefully selected cases can give a higher success rate and this method should be considered as one of the treatment modalities. PMID:25298723

Yadav, Rakesh K; Tikku, A P; Chandra, Anil; Wadhwani, K K; Ashutosh Kr; Singh, Mayank

2014-01-01

93

Ion implantation in semiconductors  

Microsoft Academic Search

Ion implantation is being applied extensively to silicon device technology. Two principle features are utilized- 1) charge control in MOS structures for threshold shift, autoregistration, and complementary wells and 2) distribution control in microwave and bipolar structures. Another feature that has not been extensively exploited is to combine the advantages of the high resolution capabilities of electric beam pattern delineation

James W. Mayer

1973-01-01

94

[Implant allergies].  

PubMed

An increasing number of patients receive and benefit from osteosynthesis materials or artificial joint replacement. The most common complications are mechanical problems or infection. Metals like nickel, chromium and cobalt as well as bone cement components like acrylates and gentamicin are potential contact allergens which can cause intolerance reactions to implants. Eczema, delayed wound/bone healing, recurrent effusions, pain and implant loosening all have been described as manifestation of implant allergy. In contrast to the high incidence of cutaneous metal allergy, allergies associated with implants are rare. Diagnosis of metal implant allergy is still difficult. Thus differential diagnoses--in particular infection--have to be excluded and a combined approach of allergologic diagnostics by patch test and histopathology of peri-implant tissue is recommended. It is still unknown which conditions induce allergic sensitization to implants or trigger peri-implant allergic reactions in the case of preexisting cutaneous metal allergy. Despite the risk of developing complications being unclear, titanium based osteosynthesis materials are recommended for metal allergic patients and the use of metal-metal couplings in arthroplasty is not recommended for such patients. If the regular CoCr-polyethylene articulation is employed, the patient should give informed written consent. PMID:20204719

Thomas, P; Thomsen, M

2010-03-01

95

The E ect of Barriers on The Tidal Range in Yong Ming Tang  

E-print Network

interest in constructing tidal barrages, either to control the tide or to extract power. CorrespondinglyThe E ect of Barriers on The Tidal Range in Estuaries Yong Ming Tang Abstract Numerical simulations of the shallow water equations are used to study the e ect of topographic barriers on the tidal range

96

Stark E ect of Interactive Electron-hole pairs in Spherical Semiconductor Quantum Dots  

E-print Network

Stark E#11;ect of Interactive Electron-hole pairs in Spherical Semiconductor Quantum Dots B in Spherical Semiconductor QDs 2 1. Introduction For about two decades, nano-structures, like quantum dots model, on the quantum-con#12;nement Stark e#11;ects for spherical semiconducting quantum dots

Recanati, Catherine

97

A Study of the E#ect of Ties in the kmodes Algorithm for Categorical data  

E-print Network

A Study of the E#ect of Ties in the k­modes Algorithm for Categorical data R. E. Funderlic, M. T Science April 28, 2004 Abstract Categorical data can easily have ties. This paper identifies two types of ties and studies their e#ect on the k­modes methods for categorical data. Three commonly used variants

98

Modelling the e#ects of air pollution on health using Bayesian Dynamic Generalised Linear Models  

E-print Network

Modelling the e#ects of air pollution on health using Bayesian Dynamic Generalised Linear Models 1 Introduction The potential detrimental e#ects of ambient air pollution is a major issue in public (2004)). Large multi­city studies such as `Air pollution and health: a European approach' (APHEA

Bath, University of

99

OIL IN THE OPEN WATER Oil in the open water may a ect the health of  

E-print Network

OIL IN THE OPEN WATER Oil in the open water may a ect the health of microscopic plants and animals. Far beneath the surface, corals and other deepwater communities might also be a ected. OIL AND HUMAN AND SEDIMENTS · Water quality surveys · Transect surveys to detect submerged oil · Oil plume modeling · Sediment

100

DIS[subscript 2]ECT: A Framework for Effective Inclusive Science Instruction  

ERIC Educational Resources Information Center

The purpose of this article is to provide special education and general education teachers a framework (DIS[subscript 2]ECT) for teaching science in inclusive settings. DIS2ECT stands for Design (Backwards); Individualization; Scaffolding and Strategies; Experiential learning; Cooperative Learning; and Teamwork. This framework was derived from our…

Spaulding, Lucinda S.; Flannagan, Jenny Sue

2012-01-01

101

EXTRACTION DE CONNAISSANCES PARTIR DES DONNEES ET DES TEXTES (ECD ET ECT "DATA & TEXT MINING")  

E-print Network

1 EXTRACTION DE CONNAISSANCES � PARTIR DES DONNEES ET DES TEXTES (ECD ET ECT "DATA & TEXT MINING'Extraction de Connaissances à partir de Textes (ECT, "Text Mining") comme un descendant direct de l'Extraction de Connaissances à partir de Données (ECD, "Data Mining"). Le point fondamental qui distingue ces

Spagnolo, Filippo

102

Microstructural E ects in Brittle Fracture with the Extended Finite Element Method  

E-print Network

Microstructural E#11;ects in Brittle Fracture with the Extended Finite Element Method N. Sukumar 1), 2001 Abstract A two-dimensional numerical model of microstructural e#11;ects in brittle fracture) is introduced in the specimen. Brittle fracture is investigated by carrying out computer simulations for varying

Sukumar, N.

103

Semiconductor Ion Implanters  

NASA Astrophysics Data System (ADS)

In 1953 the Raytheon CK722 transistor was priced at 7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at 6.2 billion! Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing `only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around 2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

MacKinnon, Barry A.; Ruffell, John P.

2011-06-01

104

Semiconductor Ion Implanters  

SciTech Connect

In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion. Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

MacKinnon, Barry A. [Isys, 2727 Walsh Ave., Suite 103, Santa Clara, CA 95051 (United States); Ruffell, John P. [Group 3, LLC, Sunnyvale, CA 94086 (United States)

2011-06-01

105

Preconditioned Alternating Projection Algorithms for Maximum a Posteriori ECT Reconstruction  

PubMed Central

We propose a preconditioned alternating projection algorithm (PAPA) for solving the maximum a posteriori (MAP) emission computed tomography (ECT) reconstruction problem. Specifically, we formulate the reconstruction problem as a constrained convex optimization problem with the total variation (TV) regularization. We then characterize the solution of the constrained convex optimization problem and show that it satisfies a system of fixed-point equations defined in terms of two proximity operators raised from the convex functions that define the TV-norm and the constrain involved in the problem. The characterization (of the solution) via the proximity operators that define two projection operators naturally leads to an alternating projection algorithm for finding the solution. For efficient numerical computation, we introduce to the alternating projection algorithm a preconditioning matrix (the EM-preconditioner) for the dense system matrix involved in the optimization problem. We prove theoretically convergence of the preconditioned alternating projection algorithm. In numerical experiments, performance of our algorithms, with an appropriately selected preconditioning matrix, is compared with performance of the conventional MAP expectation-maximization (MAP-EM) algorithm with TV regularizer (EM-TV) and that of the recently developed nested EM-TV algorithm for ECT reconstruction. Based on the numerical experiments performed in this work, we observe that the alternating projection algorithm with the EM-preconditioner outperforms significantly the EM-TV in all aspects including the convergence speed, the noise in the reconstructed images and the image quality. It also outperforms the nested EM-TV in the convergence speed while providing comparable image quality. PMID:23271835

Krol, Andrzej; Li, Si; Shen, Lixin; Xu, Yuesheng

2012-01-01

106

[Fully implantable hearing systems].  

PubMed

As yet comparatively little experience has been gained with fully implantable hearing systems, as the two systems available at present have only recently received CE permission for Europe and the FDA permissions are still pending in the USA. Additionally the technology is expensive and usually not covered by insurance companies. However, it could be shown that by careful patient selection and very careful surgical techniques, good results can be achieved with this highly sensitive technology, often with better patient satisfaction and hearing quality than with conventional hearing aids. To spread the technology further, the systems must also show reliable results on a broad application. Further surgery to change the batteries should not be necessary more frequently than with cardiac pacemakers. Not all technical problems are finally solved. However, it is to be foreseen that fully implantable hearing systems will be a good long-term alternative to conventional hearing aids for some patients. PMID:19247624

Maurer, J

2009-03-01

107

Interface Biology of Implants  

PubMed Central

Implants are widely used in various clinical disciplines to replace or stabilize organs. The challenge for the future is to apply implant materials to specifically control the biology of the surrounding tissue for repair and regeneration. This field of research is highly interdisciplinary and combines scientists from technical and life sciences disciplines. To successfully apply materials for regenerative processes in the body, the understanding of the mechanisms at the interface between cells or tissues and the artificial material is of critical importance. The research focuses on stem cells, design of material surfaces, and mechanisms of cell adhesion. For the third time around 200 scientists met in Rostock, Germany for the international symposium “Interface Biology of Implants.” The aim of the symposium is to promote the interdisciplinary dialogue between the scientists from the different disciplines to develop smart implants for medical use. In addition, researchers from basic sciences, notably cell biology presented new findings concerning mechanisms of cell adhesion to stimulate research in the applied field of implant technology. PMID:19690468

Nebe, Barbara

2009-01-01

108

Breast Implants  

MedlinePLUS

... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Medical Devices Print this page Share this page E-mail this page Home Medical Devices Products and Medical Procedures Implants and Prosthetics Breast ...

109

Speech Understanding with a New Implant Technology: A Comparative Study with a New Nonskin Penetrating Baha System  

PubMed Central

Objective. To compare hearing and speech understanding between a new, nonskin penetrating Baha system (Baha Attract) to the current Baha system using a skin-penetrating abutment. Methods. Hearing and speech understanding were measured in 16 experienced Baha users. The transmission path via the abutment was compared to a simulated Baha Attract transmission path by attaching the implantable magnet to the abutment and then by adding a sample of artificial skin and the external parts of the Baha Attract system. Four different measurements were performed: bone conduction thresholds directly through the sound processor (BC Direct), aided sound field thresholds, aided speech understanding in quiet, and aided speech understanding in noise. Results. The simulated Baha Attract transmission path introduced an attenuation starting from approximately 5?dB at 1000?Hz, increasing to 20–25?dB above 6000?Hz. However, aided sound field threshold shows smaller differences and aided speech understanding in quiet and in noise does not differ significantly between the two transmission paths. Conclusion. The Baha Attract system transmission path introduces predominately high frequency attenuation. This attenuation can be partially compensated by adequate fitting of the speech processor. No significant decrease in speech understanding in either quiet or in noise was found. PMID:25140314

Caversaccio, Marco

2014-01-01

110

Reverse engineering of ECT probes for nondestructive evaluation of moving conductors  

NASA Astrophysics Data System (ADS)

Numerical modeling of commercial ECT equipment requires preparatory work in reverse engineering. The reconstruction of given ECT probes was performed in terms of (i) geometry, (ii) material properties and source parameters, (iii) impedance computation. High-resolution X-ray images were taken in order to build appropriate CAD models of given ECT probes. An optimization strategy was applied in order to estimate the permeability of the magnetic shield as well as the supply current by means of measurement data of the magnetic flux density. Subsequently, normalized impedance calculations were performed and compared to measurements in generic benchmark models containing artificial defects.

Porzig, Konstantin; Carlstedt, Matthias; Ziolkowski, Marek; Brauer, Hartmut; Toepfer, Hannes

2014-02-01

111

Hip Implant Systems  

MedlinePLUS

... Devices Products and Medical Procedures Implants and Prosthetics Metal-on-Metal Hip Implants Section Contents Menu Products and Medical Procedures Implants and Prosthetics Metal-on-Metal Hip Implants The Hip Joint Hip ...

112

QED E ects on Inner Shells of Heavy W. R. Johnson  

E-print Network

QED E#11;ects on Inner Shells of Heavy Atoms W. R. Johnson #3; Department of Physics, University on this subject by Johnson and Cheng. [2] The experimental binding energy of a K-shell electron in a heavy atom

Johnson, Walter R.

113

Serotonergic and dopaminergic neuroendocrine responses of male depressive patients before and after a therapeutic ECT course  

Microsoft Academic Search

.  \\u000a Background: Electroconvulsive therapy (ECT) is an effective treatment for major depressive illness, even for patients who do not respond\\u000a to antidepressant drugs. According to the prevailing neurophysiological hypotheses for depression, it can be expected that\\u000a an ECT therapeutic course modulates the responsivity of central neurotransmitter systems, but the results up to now have been\\u000a inconclusive. To test such hypotheses,

Manolis Markianos; John Hatzimanolis; Lefteris Lykouras

2002-01-01

114

ECT in an Adolescent with Down Syndrome and Treatment-Refractory Major Depressive Disorder  

Microsoft Academic Search

The efficacy of electroconvulsive therapy (ECT) as a treatment for patients with major depressive disorder who are intolerant of or refractory to antidepressant medications is well known. This treatment may be overlooked in children and adolescents, and in those with developmental disabilities. The case report of a 15-year-old male with Down syndrome and treatment-refractory major depressive disorder who received ECT

Paula M. Gensheimer; Karen G. Meighen; Christopher J. McDougle

2002-01-01

115

Ion Implant  

NSDL National Science Digital Library

This website includes an animation which illustrates the ion implant process. Objective: Name the three common dopants used in implantation processes and explain the process of generating an ion beam from source to wafer. You can find this animation under the heading "Process & Equipment III." This simulation is from Module 026 of the Process & Equipment III Cluster of the MATEC Module Library (MML). To view other clusters or for more information about the MML visit http://matec.org/ps/library3/process_I.shtmlKey

2012-10-04

116

Emergency ECT in an Incapacitated, Medically Compromised Patient with Huntington's Disease.  

PubMed

Electroconvulsive therapy (ECT) is infrequently considered an "emergency" medical procedure; however, there are certain conditions in which there is considerable urgency to initiate ECT. For example, prompt administration of ECT to treat neuroleptic malignant syndrome and malignant catatonia is necessary to improve a patient's overall prognosis and potentially save the patient's life. In this case, a 57-year-old woman with Huntington's disease was admitted to our medical intensive care unit for failure to thrive due to severe psychotic symptoms. Prior to her admission, the patient had become increasingly psychotic and agitated, resulting in her refusal and/or inability to eat. Efforts to treat her severe psychiatric and behavioral symptoms with various psychopharmacological strategies were largely unsuccessful. As the patient's physical health continued to decline, with loss of approximately 35 pounds over 2 months, her family began making arrangements to transfer her to a hospice facility. The day before she was to be transferred, the psychiatry consultation-liaison service recommended ECT. Unfortunately, this recommendation was complicated because the patient was unable to provide consent. This case report describes the legal and administrative process used to ethically and legally administer ECT without consent from the patient or a court-appointed guardian in order to treat a life-threatening condition. To the best of our knowledge, this report documents the first time ECT has been granted "medical emergency" status in Texas. (Journal of Psychiatric Practice 2014;20:470-475). PMID:25406052

Magid, Michelle; Trevino, Kenneth; Reid, William H; Jalalat, Sheila; Husain, Mustafa M; Kahn, David A

2014-11-01

117

Approved Module Information for EE1ECT, 2014/5 Module Title/Name: Electrical Circuit Theory Module Code: EE1ECT  

E-print Network

Approved Module Information for EE1ECT, 2014/5 Module Title/Name: Electrical Circuit Theory Module techniques of electrical circuits to enable higher level study on electronic and communication subjects. The module will concentrate on the fundamentals of electrical DC and AC circuits with particular applications

Neirotti, Juan Pablo

118

Computer-guided implant surgery: indications and guidelines for use.  

PubMed

The introduction of medical-grade computed tomography (CT) technologies and the ballooning use of cone beam CT (CBCT) in dental offices, in combination with the use of proprietary dental implant software, has revolutionized the planning and placement of dental implants. These technologies facilitate a team approach in a truly restoratively driven treatment plan based on the accurate planning and placement of dental implants. Using this approach, the planned restoration for an implant site is first created; then the dental team, in effect, works backwards to virtually plan the ideal implant position for the site based on the anatomy, vital structures in the area, surrounding and opposing teeth and restorations, and the restoration planned. Although an argument could be made for using these technologies in most implant patients, their cost/time/benefit precludes their use in every situation. This article presents an overview of the guidelines and indications for use of computer-guided technologies in dental implant treatment. PMID:24964483

Orentlicher, Gary; Horowitz, Andrew; Abboud, Marcus

2012-01-01

119

Crystal structure of triple-BRCT-domain of ECT2 and insights into the binding characteristics to CYK-4.  

PubMed

Homo sapiens ECT2 is a cell cycle regulator that plays critical roles in cytokinesis. ECT2 activity is restrained during interphase via intra-molecular interactions that involve its N-terminal triple-BRCT-domain and its C-terminal DH-PH domain. At anaphase, this self-inhibitory mechanism is relieved by Plk1-phosphorylated CYK-4, which directly engages the ECT2 BRCT domain. To provide a structural perspective for this auto-inhibitory property, we solved the crystal structure of the ECT2 triple-BRCT-domain. In addition, we systematically analyzed the interaction between the ECT2 BRCT domains with phospho-peptides derived from its binding partner CYK-4, and have identified Ser164 as the major phospho-residue that links CYK-4 to the second ECT2 BRCT domain. PMID:25068414

Zou, Yang; Shao, Zhenhua; Peng, Junhui; Li, Fudong; Gong, Deshun; Wang, Chongyuan; Zuo, Xiaobing; Zhang, Zhiyong; Wu, Jihui; Shi, Yunyu; Gong, Qingguo

2014-08-25

120

Experimental and computational approach for the evaluation of the biomechanical e!ects of dental bridge mis\\  

Microsoft Academic Search

Dental bridges supported by osseointegrated implants are commonly used to treat the partially or completely edentulous jaw. The bridges are manufactured in metal alloy using a sequence of technological steps which well match the requirement to get custom overstructures but does not guarantee geometrical and dimensional tolerances. Dentists often experience that a perfect\\

Riccardo Pietrabissa; Roberto Contro; Virginio Quaglini; Monica Soncini; Luca Gionso; Massimo Simion

121

Effect of anatomical variability on neural stimulation strength and focality in electroconvulsive therapy (ECT) and magnetic seizure therapy (MST)  

Microsoft Academic Search

We present a quantitative comparison of two metrics-neural stimulation strength and focality-in electroconvulsive therapy (ECT) and magnetic seizure therapy (MST) using finite-element method (FEM) simulation in a spherical head model. Five stimulation modalities were modeled, including bilateral ECT, unilateral ECT, focal electrically administered seizure therapy (FEAST), and MST with circular and double-cone coils, with stimulation parameters identical to those applied

Zhi-De Deng; Sarah H. Lisanby; Angel V. Peterchev

2009-01-01

122

Electronic Communications Technologies and the Transition to College: Links to Parent-Child Attachment and Adjustment  

ERIC Educational Resources Information Center

Electronic communications technologies (ECTs) help college students and parents remain in contact. Because recent reports have emphasized a link between ECTs, helicopter parenting, and autonomy issues, this study focused on the significance of contact patterns for attachment and student adjustment. First-semester college students (199 female, 81…

Sarigiani, Pamela A.; Trumbell, Jill M.; Camarena, Phame M.

2013-01-01

123

Electroconvulsive Therapy Part I: A Perspective on the Evolution and Current Practice of ECT  

PubMed Central

The concept of inducing convulsions, mainly through chemical means, to promote mental wellness has existed since the 16th century. In 1938, Italian scientists first applied electrically induced therapeutic seizures. Although electroconvulsive therapy (ECT) is employed in the treatment of several psychiatric disorders, it is most frequently used today to treat severe depressive episodes and remains the most effective treatment available for those disorders. Despite this, ECT continues to be the most stigmatized treatment available in psychiatry, resulting in restrictions on and reduced accessibility to a helpful and potentially life-saving treatment. The psychiatric and psychosocial ramifications of this stigmatization may include the exacerbation of the increasingly serious, global health problem of major depressive disorders as well as serious consequences for individual patients who may not be offered, or may refuse, a potentially beneficial treatment. The goal of this first article in this two-part series is to provide an overview of ECT's historical development and discuss the current state of knowledge about ECT, including technical aspects of delivery, patient selection, its side-effect profile, and factors that may contribute to underuse of ECT. PMID:19820553

Payne, Nancy A.; Prudic, Joan

2010-01-01

124

Outcome of ECT by Race in the CORE Multi-Site Study  

PubMed Central

Objective The authors examine the differences in outcome between black and white patients receiving ECT as a part of the CORE multi-site study. Methods A total of 624 patients were enrolled in an NIMH-funded, randomized controlled ECT trial comparing the efficacy of continuation ECT versus continuation pharmacotherapy between 1997 and 2004. This analysis focuses on the 32 black and 483 white patients who participated in phase I of the study. The authors compared baseline demographic and clinical variables, and acute outcomes of these two groups. Results Compared to whites, far fewer blacks participated in the study. Those who did were less likely to have failed adequate medication trials and were more likely to have psychotic features. Their initial HAMD24 scores were higher than whites, and they showed a greater reduction in these HAMD24 scores by the end of the treatment period. While sample size limited the statistical significance of the findings, black patients also showed a higher rate of remission after an acute phase of ECT. Conclusions This study found that black and white patients with major depressive disorder had comparable outcomes. We also found that fewer black patients received ECT than whites, a difference that has been reported in other samples. PMID:18580553

Williams, Mark; Rummans, Teresa; Sampson, Shirlene; Knapp, Rebecca; Mueller, Martina; Husain, Mustafa M.; Fink, Max; Rasmussen, Keith; O’Connor, Kevin; Smith, Glenn; Petrides, George; Kellner, Charles H.

2014-01-01

125

ECT associated musical hallucinations in an elderly patient: a case report  

PubMed Central

Electro Convulsive Therapy (ECT) is a medical treatment for severe mental illness in which small, carefully controlled electricity is applied to the brain. This electric stimulation is done in conjunction with anesthesia and muscle relaxant medications to produce a mild generalized seizure. This is used to treat a variety of psychiatric disorders. This is most effective in the treatment of severe depression providing a rapid relief. We report and discuss an unusual presentation of a ninety three year old lady with a diagnosis of Major Depressive Disorder, Recurrent, Severe with Psychotic features (296.34) who experienced musical hallucinations whilst she was treated on ECT. Clinically there was an inverse relationship between the biological symptoms of depression and musical hallucination during the ECT management. Though similar reports have never been reported earlier, we noticed a good association between the initiation of ECT and musical hallucination in our patient. The patient stopped experiencing musical hallucinations and improved of her biological symptoms of depression completely after the full course of ECT. PMID:16889667

Janakiraman, Raguraman; Wildgoose, Keith; Seelam, Kalyan

2006-01-01

126

Photobiomodulation and implants: implications for dentistry  

PubMed Central

The use of dental implants has become a mainstay of rehabilitative and restorative dentistry. With an impressive clinical success rate, there remain a few minor clinical issues with the use of implants such as peri-implant mucositis and peri-implantitis. The use of laser technology with implants has a fascinating breadth of applications, beginning from their precision manufacturing to clinical uses for surgical site preparation, reducing pain and inflammation, and promoting osseointegration and tissue regeneration. This latter aspect is the focus of this review, which outlines various studies of implants and laser therapy in animal models. The use of low level light therapy or photobiomodulation has demonstrated its efficacy in these studies. Besides more research studies to understand its molecular mechanisms, significant efforts are needed to standardize the clinical dosing and delivery protocols for laser therapy to ensure the maximal efficacy and safety of this potent clinical tool for photobiomodulation. PMID:24455438

Tang, Elieza

2013-01-01

127

Nanostructured Surfaces of Dental Implants  

PubMed Central

The structural and functional fusion of the surface of the dental implant with the surrounding bone (osseointegration) is crucial for the short and long term outcome of the device. In recent years, the enhancement of bone formation at the bone-implant interface has been achieved through the modulation of osteoblasts adhesion and spreading, induced by structural modifications of the implant surface, particularly at the nanoscale level. In this context, traditional chemical and physical processes find new applications to achieve the best dental implant technology. This review provides an overview of the most common manufacture techniques and the related cells-surface interactions and modulation. A Medline and a hand search were conducted to identify studies concerning nanostructuration of implant surface and their related biological interaction. In this paper, we stressed the importance of the modifications on dental implant surfaces at the nanometric level. Nowadays, there is still little evidence of the long-term benefits of nanofeatures, as the promising results achieved in vitro and in animals have still to be confirmed in humans. However, the increasing interest in nanotechnology is undoubted and more research is going to be published in the coming years. PMID:23344062

Bressan, Eriberto; Sbricoli, Luca; Guazzo, Riccardo; Tocco, Ilaria; Roman, Marco; Vindigni, Vincenzo; Stellini, Edoardo; Gardin, Chiara; Ferroni, Letizia; Sivolella, Stefano; Zavan, Barbara

2013-01-01

128

Decaborane implantation with the medium current implanter  

NASA Astrophysics Data System (ADS)

A decaborane implantation system has been developed. The maximum beam current achieved at a wafer is 30 ?A at 5 keV with the divergence less than 0.4°, which corresponds to the equivalent 500 eV-300 ?A boron monomer implantation without an energy contamination. As-implanted secondary ion mass spectroscopy (SIMS) profile of the decaborane implanted at the equivalent energy 500 eV shows the steeper and shallower profile than that of the boron implanted. The result of Rs- Xj proves the higher activation with shallower junction depth. These advantages possibly arise from the self-amorphization layer by the decaborane implantation.

Hamamoto, Nariaki; Umisedo, Sei; Nagayama, Tsutomu; Tanjyo, Masayasu; Sakai, Shigeki; Nagai, Nobuo; Aoyama, Takayuki; Nara, Yasuo

2005-08-01

129

ACTIVE PLATELET 5-HT UPTAKE IN DEPRESSIVES TREATED WITH IMPRAMINE AND ECT  

PubMed Central

Several studies have reported decreased platelet 5-HT uptake in patients of major depression. The present study was undertaken with the aim to study the active platelet 5-HT uptake in depressed patients and effect of treatment with imipramine/ECT on platelet 5-HT uptake in these patients. 30 patients of major depression and equal number of age and sex-matched controls were included in the study. The depressives received imipramine (N=15) or ECT (N=15). Pretreatment active platelet 5-HT uptake was lower in depressives. Treatment with imipramine resulted in significant decrease in 5-HT uptake while with ECT there was significant increase. The serotonergic mechanisms are discussed. PMID:21494445

Dalal, P.K.; Lal, Narottam; Trivedi, J.K.; Seth, P.K.; Agarwal, A.K.; Khalid, Abdul

1998-01-01

130

Appraisal of evidence base for introduction of new implants in hip and knee replacement: a systematic review of five widely used device technologies  

PubMed Central

Objective To determine the evidence of effectiveness and safety for introduction of five recent and ostensibly high value implantable devices in major joint replacement to illustrate the need for change and inform guidance on evidence based introduction of new implants into healthcare. Design Systematic review of clinical trials, comparative observational studies, and registries for comparative effectiveness and safety of five implantable device innovations. Data sources PubMed (Medline), Embase, Web of Science, Cochrane, CINAHL, reference lists of articles, annual reports of major registries, summaries of safety and effectiveness for pre-market application and mandated post-market studies at the US Food and Drug Administration. Study selection The five selected innovations comprised three in total hip replacement (ceramic-on-ceramic bearings, modular femoral necks, and uncemented monoblock cups) and two in total knee replacement (high flexion knee replacement and gender specific knee replacement). All clinical studies of primary total hip or knee replacement for symptomatic osteoarthritis in adults that compared at least one of the clinical outcomes of interest (patient centred outcomes or complications, or both) in the new implant group and control implant group were considered. Data searching, abstraction, and analysis were independently performed and confirmed by at least two authors. Quantitative data syntheses were performed when feasible. Results After assessment of 10?557 search hits, 118 studies (94 unique study cohorts) met the inclusion criteria and reported data related to 15?384 implants in 13?164 patients. Comparative evidence per device innovation varied from four low to moderate quality retrospective studies (modular femoral necks) to 56 studies of varying quality including seven high quality (randomised) studies (high flexion knee replacement). None of the five device innovations was found to improve functional or patient reported outcomes. National registries reported two to 12 year follow-up for revision occurrence related to more than 200?000 of these implants. Reported comparative data with well established alternative devices (over 1?200?000 implants) did not show improved device survival. Moreover, we found higher revision occurrence associated with modular femoral necks (hazard ratio 1.9) and ceramic-on-ceramic bearings (hazard ratio 1.0-1.6) in hip replacement and with high flexion knee implants (hazard ratio 1.0-1.8). Conclusion We did not find convincing high quality evidence supporting the use of five substantial, well known, and already implemented device innovations in orthopaedics. Moreover, existing devices may be safer to use in total hip or knee replacement. Improved regulation and professional society oversight are necessary to prevent patients from being further exposed to these and future innovations introduced without proper evidence of improved clinical efficacy and safety. PMID:25208953

Nieuwenhuijse, Marc J; Nelissen, R G H H; Schoones, J W

2014-01-01

131

Vanishing Electronic Medical Implants  

NSDL National Science Digital Library

Scientists have developed a new class of electronics capable of degrading into their environment. Unlike todayâÂÂs electronic devices, which are designed to last forever, the transient circuits developed by Suk-Won Hwang and colleagues disappear after a programmed amount of time. The technology could be useful in biomedical implants to help treat surgical infections or stimulate bone growth. The researchers crafted electronic circuits from cocoon silk, thin sheets of porous silicon and magnesium electrodes -- materials all capable of disappearing or resorbing into their environment.

Nadia Ramlagan (Science;)

2012-09-28

132

Osteogenic activity and antibacterial effect of zinc ion implanted titanium.  

PubMed

Titanium (Ti) and its alloys are widely used as orthopedic and dental implants. In this work, zinc (Zn) was implanted into oxalic acid etched titanium using plasma immersion ion implantation technology. Scanning electron microscopy and X-ray photoelectron spectroscopy were used to investigate the surface morphology and composition of Zn-implanted titanium. The results indicate that the depth profile of zinc in Zn-implanted titanium resembles a Gaussian distribution, and zinc exists in the form of ZnO at the surface whereas in the form of metallic Zn in the interior. The Zn-implanted titanium can significantly stimulate proliferation of osteoblastic MC3T3-E1 cells as well as initial adhesion, spreading activity, ALP activity, collagen secretion and extracellular matrix mineralization of the rat mesenchymal stem cells. The Zn-implanted titanium presents partly antibacterial effect on both Escherichia coli and Staphylococcus aureus. The ability of the Zn-implanted titanium to stimulate cell adhesion, proliferation and differentiation as well as the antibacterial effect on E. coli can be improved by increasing implantation time even to 2 h in this work, indicating that the content of zinc implanted in titanium can easily be controlled within the safe concentration using plasma immersion ion implantation technology. The Zn-implanted titanium with excellent osteogenic activity and partly antibacterial effect can serve as useful candidates for orthopedic and dental implants. PMID:24632388

Jin, Guodong; Cao, Huiliang; Qiao, Yuqin; Meng, Fanhao; Zhu, Hongqin; Liu, Xuanyong

2014-05-01

133

Decaborane implantation with the medium current implanter  

Microsoft Academic Search

A decaborane implantation system has been developed. The maximum beam current achieved at a wafer is 30?A at 5keV with the divergence less than 0.4°, which corresponds to the equivalent 500eV–300?A boron monomer implantation without an energy contamination. As-implanted secondary ion mass spectroscopy (SIMS) profile of the decaborane implanted at the equivalent energy 500eV shows the steeper and shallower profile

Nariaki Hamamoto; Sei Umisedo; Tsutomu Nagayama; Masayasu Tanjyo; Shigeki Sakai; Nobuo Nagai; Takayuki Aoyama; Yasuo Nara

2005-01-01

134

Fast Particle Finite Orbit Width and Larmor Radius E ects on Low-n Toroidicity induced Alfv en Eigenmode Excitation  

E-print Network

Fast Particle Finite Orbit Width and Larmor Radius E ects on Low-n Toroidicity induced Alfv en 451 Princeton, NJ 08543-0451 January 13, 1999 The e ects of nite drift orbit width FOW and nite Larmor !c is particle cy- clotron frequency by following the particle drift orbit and thus fully retains

135

2008 Ect Benchmark Results: Modeling with Civa of 3d Flaws Responses in Planar and Cylindrical Work Pieces  

Microsoft Academic Search

The configurations proposed in the 2008 ECT modeling benchmark session are addressed in this paper using the eddy current modeling tool embedded into CIVA, which is a multi-technique simulation platform dedicated to NDT and developed at the French Atomic Energy Commission (CEA). The theoretical approach used in CIVA for ECT modeling is based on Volume integral Method (VIM) coupled with

C. Reboud; G. Pichenot; D. Prémel; R. Raillon

2009-01-01

136

[Comperative study of implant surface characteristics].  

PubMed

The osseointegration between the implant and its' bone environment is very important. The implants shall meet the following requirements: biocompatibility, rigidity, resistance against corrosion and technical producibility. In our present study surface morphology and material characteristics of different implants (Denti Bone Level, Denti Zirconium C, Bionika CorticaL, Straumann SLA, Straumann SLA Active, Dentsply Ankylos and Biotech Kontact implant) were investigated with scanning electron microscopy and energy-dispersive X-ray spectroscopy. The possible surface alterations caused by the manufacturing technology were also investigated. During grit-blasting the implants' surface is blasted with hard ceramic particles (titanium oxide, alumina, calcium phosphate). Properties of blasting material are critical because the osseointegration of dental implants should not be hampered. The physical and chemical features of blasting particles could importantly affect the produced surfaces of implants. Titanium surfaces with micro pits are created after immersion in mixtures of strong acids. On surfaces after dual acid-etching procedures the crosslinking between fibrin and osteogenetic cells could be enhanced therefore bone formation could be directly facilitated on the surface of the implant. Nowadays there are a number of surface modification techniques available. These can be used as a single method or in combination with each other. The effect of the two most commonly used surface modifications (acid-etching and grit-blasting) on different implants are demonstrated in our investigation. PMID:24551957

Katona, Bernadett; Daróczi, Lajos; Jenei, Attila; Bakó, József; Hegedus, Csaba

2013-12-01

137

Ethics of Academic Research (2 ECTS) Responsible Conduct of Research (RCR) and Scientific Misconduct  

E-print Network

Ethics of Academic Research (2 ECTS) Contents: · Responsible Conduct of Research (RCR) and Scientific Misconduct · Ethical (Pre-)Review and the RCR Investigation Process · Questions Pertaining to All authorship, peer review, mentor/trainee responsibilities) · Discipline-Specific Ethical Issues (human

Wahlberg, Niklas

138

Master's project in biology/immunology, 30 and 45 ECTS Exploring autoreactive B lymphocytes  

E-print Network

Master's project in biology/immunology, 30 and 45 ECTS Exploring autoreactive B lymphocytes Project of immunological techniques and equipment - Weekly lab meetings, journal clubs and seminars in immunology have a relevant background with completed courses in immunology and/or infectious biology. -Experience

Uppsala Universitet

139

The e#ect of circuit parameters on ferroresonant solutions in an LCR circuit  

E-print Network

­ sponse of a laboratory­scale transformer and numerically simulate a series LCR circuit. Excellent of operating conditions for a sinusoidally­driven series LCR circuit. This is one of the simplest circuitsThe e#ect of circuit parameters on ferroresonant solutions in an LCR circuit H. LAMBA # S. Mc

Lamba, Harbir

140

An Assessment of the ECTS in Software Engineering: A Teaching Experience  

ERIC Educational Resources Information Center

Spain is currently implementing the regulatory modifications promulgated by the Declaration of Bologna, which should result in the updating of the structure of university degrees, and the inclusion of the European Credit Transfer and Accumulation System (ECTS) methodology. In some Spanish universities, the experimental adoption of this methodology…

Salas-Morera, L.; Berral-Yeron, J.; Serrano-Gomez, I.; Martinez-Jimenez, P.

2009-01-01

141

A Study of the E ects of Compiler-Controlled Speculation on Instruction and Data Caches  

E-print Network

A Study of the E ects of Compiler-Controlled Speculation on Instruction and Data Caches Roger A. Bringmann Scott A. Mahlke y Wen-mei W. Hwu Center for Reliable and High-Performance Computing University of Illinois Urbana, IL 61801 Abstract Compiler-controlled speculation has been shown to be e ec- tive

Mahlke, Scott A.

142

Applying the ECTS System to the Childhood Education Teaching Degree in Andalusia  

ERIC Educational Resources Information Center

This article presents the research conducted as part of a Pilot Experiment regarding the application of the ECTS to the Childhood Education Teaching Degree taught at the University of Cordoba (Spain). It analyses the Experiment, which was carried out in the Education Faculty over the course of three academic years (2004/05, 2005/06 and 2006/07).…

Serrano, Rosario Merida; Romero, Julia Angulo; Del Pino, Carmen Gil

2008-01-01

143

Detecting Pulsatile Hormone Secretions Using Nonlinear Mixed E#ects Partial Spline Models  

E-print Network

Detecting Pulsatile Hormone Secretions Using Nonlinear Mixed E#ects Partial Spline Models Yu signaling. The identification of episodic releases of hormonal pulse signals constitutes a major emphasis hormone concentration measurements is of critical importance in endocrinology. In this paper, we propose

Wang, Yuedong

144

The E ect of Correlating Quantum Allocation and Job Size for Gang Scheduling ?  

E-print Network

The E ect of Correlating Quantum Allocation and Job Size for Gang Scheduling ? Gaurav Ghare Scott T,leutg@cs.du.edu Abstract. Gang scheduling is an e ective scheduling policy for multi- processing workloads with signi cant has generalized and re ned the coscheduling (now often called gang scheduling) concept 5,6,8,9,11, 14

Feitelson, Dror

145

ccsd00000448 Swelling of phospholipid oating bilayers: the e ect of chain length  

E-print Network

ccsd­00000448 (version 1) : 26 Jun 2003 Swelling of phospholipid oating bilayers: the e#11;ect of a homogeneous lipid bilayer, oating near an identical bilayer deposited on the hydrophilic surface of a silicon, n, varying from 16 to 20. The average and r.m.s. positions of the oating bilayer were determined

146

Top Ten Reasons a Graduate Student Should Apply to Be an ECT Foundation Intern  

ERIC Educational Resources Information Center

In this article, the author encourages graduate students to apply for the ECT Foundation Internship. She presents a list of the top ten benefits the internship offers a graduate student's career: (1) It could change your life. It changed mine; (2) Networking; (3) Mentoring; (4) Leadership opportunities; (5) Behind the scenes pass; (6) Shadowing;…

York, Cindy S.

2009-01-01

147

Initial Results from a Study of the E ects of Meditation on Multitasking Performance  

E-print Network

Initial Results from a Study of the E ects of Meditation on Multitasking Performance MEDITATION CONTROL MEDITATION RELAXATION 8 weeks 8 weeks memorytask performance/strategy None of the groups showed the meditation group demonstrated a major change in multi- tasking strategy, namely, a marked tendency to spend

Wobbrock, Jacob O.

148

Modeling Transport E ects on Ground-Level Ozone Using a  

E-print Network

Modeling Transport E ects on Ground-Level Ozone Using a Non-Stationary Space-Time Model Hsin on Ground-Level Ozone 1 #12;Summary This article presents a novel autoregressive space-time model for ground-level ozone data, which models not only spatio-temporal dynamics of hourly ozone con- centrations, but also

Huang, Su-Yun

149

Climate Change Eff ects on Runoff , Catchment Phosphorus Loading and Lake Ecological State, and Potential Adaptations  

Microsoft Academic Search

Climate change may have profound eff ects on phosphorus (P) transport in streams and on lake eutrophication. Phosphorus loading from land to streams is expected to increase in northern temperate coastal regions due to higher winter rainfall and to a decline in warm temperate and arid climates. Model results suggest a 3.3 to 16.5% increase within the next 100 yr

Martin Søndergaard; Kristina M. Hansen; Hans E. Andersen; Torben L. Lauridsen; Lone Liboriussen

150

Identifying Pathways and Processes Aff ecting Nitrate and Orthophosphate Inputs to Streams in Agricultural Watersheds  

Microsoft Academic Search

Understanding nutrient pathways to streams will improve nutrient management strategies and estimates of the time lag between when changes in land use practices occur and when water quality eff ects that result from these changes are observed. Nitrate and orthophosphate (OP) concentrations in several environmental compartments were examined in watersheds having a range of base fl ow index (BFI) values

Anthony J. Tesoriero; John H. Duff; David M. Wolock; Norman E. Spahr USGS

151

Macroeconomic E?ects of Regulation and Deregulation in Goods and Labor Markets  

Microsoft Academic Search

Abstract Product and labor market deregulation are fundamentally about reducing and redistributing rents, leading economic players to adjust in turn to this new distribution. Thus, even if deregulation eventu- ally proves bene¯cial, it comes with strong distribution and dynamic e®ects. The transition may imply the decline of incumbent ¯rms. Un- employment may increase for a while. Real wages may decrease

O. J Blanchard; F. Giavazzi

2001-01-01

152

Retrograde peri-implantitis  

PubMed Central

Retrograde peri-implantitis constitutes an important cause for implant failure. Retrograde peri-implantitis may sometimes prove difficult to identify and hence institution of early treatment may not be possible. This paper presents a report of four cases of (the implant placed developing to) retrograde peri-implantitis. Three of these implants were successfully restored to their fully functional state while one was lost due to extensive damage. The paper highlights the importance of recognizing the etiopathogenic mechanisms, preoperative assessment, and a strong postoperative maintenance protocol to avoid retrograde peri-implant inflammation. PMID:20922082

Mohamed, Jumshad B.; Shivakumar, B.; Sudarsan, Sabitha; Arun, K. V.; Kumar, T. S. S.

2010-01-01

153

Ganciclovir implants (Vitrasert).  

PubMed

Ganciclovir implants, used for treating CMV retinitis, are effective in stemming the progression of CMV in patients already diagnosed with the disease. The implants need to be replaced after 32 weeks to lessen the likelihood of relapse. Studies show ganciclovir implants improve eyesight in the majority of patients using them. One large trial, comparing implants with other ganciclovir delivery methods, shows implants to be superior in halting CMV progression. A drawback of the implants is that because they release the drug into the eye only, CMV can spread to other parts of the body. A pill form of the drug is available to use in combination with the implant. PMID:11363393

1996-04-01

154

Some Considerations of the Tolerability of Ketamine for ECT Anesthesia: A Case Series and Review of the Literature.  

PubMed

Most anesthetic agents used for electroconvulsive therapy (ECT) have few intrinsic adverse effects. Ketamine, however, is well known to be associated with a variety of adverse effects including nausea, dizziness, and psychotomimetic phenomena. Over the past several decades, there have been numerous reports on the use of ketamine for ECT anesthesia, with varied assessments on how prominent these adverse effects are in the ECT situation. Ketamine has received a resurgence of interest as an ECT anesthetic of late owing to its established independent antidepressant effects and to theoretical reasons why it might lessen the cognitive adverse effects of ECT. In this case series, the author reviews the experience with 14 patients who had undergone ECT who were switched to ketamine as anesthetic from methohexital at the preference of the treating anesthesiologist. All 14 patients spontaneously reported a strong preference not to be given ketamine again due to bothersome adverse effects. The latter consisted of either vestibular-type symptoms (nausea/vomiting, dizziness, and vertigo) or psychotomimetic effects (dissociative phenomena). It is concluded that ketamine is not free of adverse effects when used as an ECT anesthetic. Electroconvulsive therapy clinicians should be vigilant about assessing for these effects when ketamine is used, and consideration should be given to using a benzodiazepine such as diazepam or midazolam at seizure termination when ketamine anesthesia is used to prevent bothersome adverse effects seen upon awakening. PMID:24820945

Rasmussen, Keith G; Ritter, Matthew J

2014-12-01

155

Fabricating specialised orthopaedic implants using additive manufacturing  

NASA Astrophysics Data System (ADS)

It has been hypothesised that AM is ideal for patient specific orthopaedic implants such as those used in bone cancer treatment, that can rapidly build structures such as lattices for bone and tissues to in-grow, that would be impossible using current conventional subtractive manufacturing techniques. The aim of this study was to describe the adoption of AM (direct metal laser sintering and electron beam melting) into the design manufacturing and post-manufacturing processes and the early clinical use. Prior to the clinical use of AM implants, extensive metallurgical and mechanical testing of both laser and electron beam fabrications were undertaken. Concurrently, post-manufacturing processes evaluated included hipping, cleaning and coating treatments. The first clinical application of a titanium alloy mega-implant was undertaken in November 2010. A 3D model of the pelvic wing implant was designed from CT scans. Novel key features included extensive lattice structures at the bone interfaces and integral flanges to fix the implant to the bone. The pelvic device was implanted with the aid of navigation and to date the patient remains active. A further 18 patient specific mega-implants have now been implanted. The early use of this advanced manufacturing route for patient specific implants has been very encouraging enabling the engineer to produce more advanced and anatomical conforming implants. However, there are a new set of design, manufacturing and regulatory challenges that require addressing to permit this technique to be used more widely. This technology is changing the design and manufacturing paradigm for the fabrication of specialised orthopaedic implants.

Unwin, Paul

2014-03-01

156

Subcutaneous implantable cardiac defibrillators: indications and limitations.  

PubMed

The implantable cardioverter defibrillator is today an indisputable evidence-based treatment for cardiac sudden death both in primary and secondary prevention. However, trans-venous cardioverter defibrillator implantation still carries a not negligible risk of complications both acutely and during follow-up. Trans-venous endocardial lead is the weak link of implantable cardioverter defibrillator (ICD) technology being the source of most mechanical complications on vessels and heart structures and exposed to infection, malfunction and recalls. A totally subcutaneous defibrillation lead has recently been introduced in clinical practice. With the subcutaneous pulse generator forms a defibrillation system that leaves the vessels and the heart completely "untouched." Subcutaneous ICD has proven to be safe and effective in many clinical trials. Patients without pacing indications and at higher risk of complications from trans-venous lead implantation represent the perfect candidates to S-ICD technology. However, with technical improvement, it is reasonable to expect a further expansion of indications. PMID:25475178

Bongiorni, Maria Grazia; Viani, Stefano; Zucchelli, Giulio; Di Cori, Andrea; Segreti, Luca; Paperini, Luca; Levorato, Dianora; Boem, Adriano; Branchitta, Giulia; Andreini, Diana; Soldati, Ezio

2015-02-01

157

A Case Report of Prolonged Apnea during ECT in a Patient with Suicidal Attempt by Organophosphorus Poison.  

PubMed

Organophosphorus pesticides have been used in some cases for suicidal attempts. Such poison can affect plasma cholinesterase activity. The case was a 47-year-old man hospitalized due to suicide attempt with swallowing agricultural poison. The patient, diagnosed with major depressive disorder (MDD), underwent treatment with electroconvulsive therapy (ECT). At the first ECT session, the patient developed apnea for 45 minutes following receiving 20 mg succinylcholine. The patient was intubated; after restoration of respiration depth and rate, the patient was extubated. Collectively, in cases with history of suicide attempts, taking organophosphorus pesticides should be warn for pre-ECT anesthesia. PMID:24644472

Moudi, Sussan; Alijanpour, Ebrahim; Manouchehri, Ali-Asghar; Jafarian, Hasan

2012-01-01

158

Science Highlights from the RBSP-ECT Particle Instrument Suite on NASA's Van Allen Probes Mission  

NASA Astrophysics Data System (ADS)

The NASA Van Allen Probes mission includes an instrument suite known as the Radiation Belt Storm Probes (RBSP) - Energetic Particle, Composition, and Thermal Plasma (ECT) suite. RBSP-ECT contains a well-proven complement of particle instruments to ensure the highest quality measurements ever made in the radiation belts and the inner magnetosphere. The coordinated RBSP-ECT particle measurements, analyzed in combination with fields and waves observations and state of-the-art theory and modeling, provide new understanding on the acceleration, global distribution, and variability of radiation belt electrons and ions, key science objectives of NASA's Living With a Star program and the Van Allen Probes mission. The RBSP-ECT suite consists of three highly-coordinated instruments: the Helium Oxygen Proton Electron (HOPE) spectrometer, the Magnetic Electron Ion Spectrometer (MagEIS), and the Relativistic Electron Proton Telescope (REPT). Collectively these three instrument types cover comprehensively the full electron and ion spectra from one eV to 10's of MeV with sufficient energy resolution, pitch angle coverage and resolution, and with composition measurements in the critical energy range up to 50 keV and also from a few to 50 MeV/nucleon. All three instruments are based on measurement techniques proven in the radiation belts, then optimized to provide unambiguous separation of ions and electrons and clean energy responses even in the presence of extreme penetrating background environments. In this presentation, we summarize overall ECT science goals and then show scientific results derived from the ECT suite on the dual Van Allen Probes spacecraft to date. Mission operations began only in late October 2012, and we have now achieved significant results. Results presented here will include substantial progress toward resolving primary Van Allen Probes science targets, such as: the relative role of localized acceleration versus transport-generated particle acceleration; the role of plasma electron temperature anisotropies, whistler waves, and radiation belt electron variability; global characteristics of outer zone electron drift loss to the magnetopause; the role of storms, substorms, and ion composition in radiation belt dynamics, both in terms of sources and sinks; new physical perspectives on inner zone and slot protons and electrons; and, how plasmasphere properties control or influence radiation belt behavior.

Spence, Harlan

2014-05-01

159

Rehabilitation of deaf persons with cochlear implants  

Microsoft Academic Search

Summary  \\u000a In the last decade, the rehabilitation of postlingually deaf adults and prelingually deaf children with cochlear implants\\u000a has been established as a treatment of deafness. The technological development of the implant devices and improvement of the\\u000a surgical technique have led to a considerable increase of hearing performance during the last years. The postlingually deaf\\u000a adults are able to use

W. Gstoettner; J. Hamzavi; C. Czerny

1997-01-01

160

CAD/CAM guided surgery in implant dentistry: a brief review.  

PubMed

Advanced imaging and CAD/CAM technologies and their applications in enhancing treatment outcomes in implant dentistry have gained widespread interest. Guided implant surgery utilizing these advanced technologies has significant applications in implant dentistry. This article provides information on some of the perceived advantages and disadvantages for planning guided versus conventional implant surgery as well as basic steps involved in the fabrication of guided surgical templates (GST). PMID:24881444

Kattadiyil, Mathew T; Parciak, Ewa; Puri, Shweta; Scherer, Michael D

2014-01-01

161

ECT imaging of three-phase fluidized bed based on three-phase capacitance model  

Microsoft Academic Search

In this work, the electrical capacitance tomography (ECT) with neural network multi-criteria optimization image reconstruction technique (NN-MOIRT), early developed by the authors, is applied to imaging bubble column and three-phase fluidized bed systems in the real time manner. Air, norpar (paraffin) and glass-beads are used as the gas, liquid, and solid phases, respectively. A three-phase capacitance model coupled with a

W Warsito; L.-S Fan

2003-01-01

162

Perturbative approach to compute sensitivity matrix elements in electrical capacitance tomography (ECT) of flow systems  

Microsoft Academic Search

We describe an efficient way to compute the sensitivity matrix for electrical capacitance tomography (ECT). The sensitivity matrix is used in conjunction with a neural-network based multi-criterion optimization image reconstruction technique (NN-MOIRT) designed for 3D realtime imaging of three-phase flow systems. We adopt a perturbative approach for the calculation of the sensitivity matrix for very small pixel sizes (higher resolutions).

Q. Marashdeh; F. L. Teixeira

2003-01-01

163

English Bachelor Modules Dep. EI 09/14 Modul ID Modulbezeichnung Sem. ECTS  

E-print Network

English Bachelor Modules Dep. EI 09/14 Modul ID Modulbezeichnung Sem. ECTS Lehrform V/�/P SWS Prüfungsart Spra- che EI0679 Basic Laboratory Course on Telecommunications WS/SS 5 0/0/4 4 7x s, 30 min (je 1/7) E EI0554 Blockpraktikum C++ WS/SS 6 2/0/4 6 s, 60 min (60%) + m (40%) + l (SL) D/E EI0607

Kuehnlenz, Kolja

164

Test Particle Simulation of Thermal Plasma Distribution Observed by the HOPE Instrument on RBSP-ECT  

NASA Astrophysics Data System (ADS)

We analyze and simulate the `first-light' plasmaspheric thermal plasma measurements from the Helium Oxygen Proton Electron (HOPE) instruments, part of the Energetic Particle, Composition, and Thermal Plasma Suite (ECT) onboard the Radiation Belts Storm Probes (RBSP) mission. A plasmaspheric test particle (PTP) simulation is run to reproduce and provide global contextual information for the dawnside HOPE observations, allowing us to estimate the thermal plasma environment experienced by radiation belt electrons.

Goldstein, J.; Spence, H. E.; Reeves, G. D.; Thomsen, M. F.; Skoug, R. M.; Funsten, H. O.; Livi, R.

2012-12-01

165

Effects of zopicloone and Lorazepam on ect seizure duration : clinical implications of findings from an animal model.  

PubMed

Lorazepam is commonly prescribed to treat insomnia in depressed patients who receive electroconvulsive therapy (ECT); however, lorazepam may interfere with ECT seizure parameters, and may thereby compromise the efficacy of the treatment. This study therefore sought to assess whether zopicione, a hypnotic agent, interferes less with the ECT seizure. For ethical reasons, the study utilized an animal model. Sprague-Dawley rats (n=10/group) received either zopicione (1.5 mg/ kg), lorazepam (0.2 mg/kg), or a placebo equivalent. After 30 minutes, an electroconvulsive shock was administered to the rats. It was observed that the motor seizure duration but not the total motoric phase was significantly attenuated by zopicione. Lorazepam did not impact significantly upon either seizure measure. It is concluded that zopicione may be a suitable hypnotic for patients receiving ECT only if sufficient time is allowed for the drug to be substantially washed out of the body. PMID:21407962

Andrade, C; Reddy, K P; Srihari, B S; Sudha, S; Chandra, J S

2000-07-01

166

Breast reconstruction - implants  

MedlinePLUS

... be filled with either saline or a silicone gel. You may have another minor procedure later that ... breast reconstruction with implants are: The implant may break or leak in the first 10 years. If ...

167

The Ion Implanter  

NSDL National Science Digital Library

This web site displays and describes the major components of a modern high current ion implanter. It uses a series of clickable image maps to help navigate. The site describes the entire process of ion implantation.

2012-07-31

168

Usability of ECT for quantitative and qualitative characterization of trickle-bed flow dynamics subject to filtration conditions  

Microsoft Academic Search

This work investigates the pros and cons related to the use of the electrical capacitance tomography (ECT) technique for the imaging and the quantitative characterization of flow dynamics that develop in a four-phase trickle-bed reactor. The use of ECT in non-invasive imaging is increasing continuously owing to its low cost and technical convenience when compared to other tomography methods, such

Cristian Tibirna; David Edouard; André Fortin; Faïçal Larachi

2006-01-01

169

Decaborane ion implantation  

Microsoft Academic Search

The continued scaling of integrated circuit devices has resulted in the need for lower and lower implant energy capabilities. The difficulties associated with extraction and transport of low energy beams have lead to research in novel techniques for ultra low energy implantation. Results from one such technique, decaborane ion implantation, are reported here. Decaborane is a molecule with 10 boron

A. S. Perel; W. Krull; D. Hoglund; K. Jackson; T. Horsky

2000-01-01

170

Ablation plasma ion implantation  

Microsoft Academic Search

The novel hybrid technique, Ablation Plasma Ion Implantation (APII), has been characterized and optimized for ion implantation and\\/or thin film deposition. In APII, a solid target is ablated by a laser; the resulting plasma plume is the source of ions, which are accelerated to high energy by a negative bias voltage imposed on the substrate. The ions are implanted into

Bo Qi

2002-01-01

171

Rapid Response of Long-Standing, Treatment-Resistant Non-Catatonic Mutism in Paranoid Schizophrenia with Single ECT session  

PubMed Central

Context: Mutism is a common manifestation of catatonia, but mutism due to other forms of psychopathology and neurological disorders have also been described. Although not common, long-standing mutism has also been a feature of non-catatonic schizophrenia and traditionally responds less to conventional therapies. Case Report: We describe a rare case of paranoid schizophrenia presenting with continuous mutism for about 4 years. This 26-year-old male had symptoms of schizophrenia without catatonia. After failed trial of adequate pharmacotherapy and psychological intervention and considering his level of dysfunction, he was started on electroconvulsive therapy (ECT). To our surprise, he improved with a single session of ECT while he was on concurrent pharmacotherapy. We also discuss the possible explanation for this rapid effect of ECT in such clinical presentation. To our knowledge, this is the first case of non-catatonic mutism of schizophrenia of this long duration responding so promptly to ECT, although there are other reports as well in literature, but multiple ECT sessions were applied in those cases. Conclusion: Non-catatonic mutism is perhaps presenting as a cultural variant in this part of the world and whenever encountered, ECT should be an option. Further research should be carried out to validate this idea.

Dar, Mansoor Ahmad; Rather, Yasir Hassan; Shah, Majid Shafi; Wani, Rayees Ahmad; Hussain, Arshad

2014-01-01

172

Biomedical Imaging in Implantable Drug Delivery Systems.  

PubMed

Implantable drug delivery systems (DDS) provide a platform for sustained release of therapeutic agents over a period of weeks to months and sometimes years. Such strategies are typically used clinically to increase patient compliance by replacing frequent administration of drugs such as contraceptives and hormones to maintain plasma concentration within the therapeutic window. Implantable or injectable systems have also been investigated as a means of local drug administration which favors high drug concentration at a site of interest, such as a tumor, while reducing systemic drug exposure to minimize unwanted side effects. Significant advances in the field of local DDS have led to increasingly sophisticated technology with new challenges including quantification of local and systemic pharmacokinetics and implant-body interactions. Because many of these sought-after parameters are highly dependent on the tissue properties at the implantation site, and rarely represented adequately with in vitro models, new nondestructive techniques that can be used to study implants in situ are highly desirable. Versatile imaging tools can meet this need and provide quantitative data on morphological and functional aspects of implantable systems. The focus of this review article is an overview of current biomedical imaging techniques, including magnetic resonance imaging (MRI), ultrasound imaging, optical imaging, X-ray and computed tomography (CT), and their application in evaluation of implantable DDS. PMID:25418857

Zhou, Haoyan; Hernandez, Christopher; Goss, Monika; Gawlik, Anna; Exner, Agata A

2014-11-22

173

Miniaturized neural interfaces and implants  

NASA Astrophysics Data System (ADS)

Neural prostheses are technical systems that interface nerves to treat the symptoms of neurological diseases and to restore sensory of motor functions of the body. Success stories have been written with the cochlear implant to restore hearing, with spinal cord stimulators to treat chronic pain as well as urge incontinence, and with deep brain stimulators in patients suffering from Parkinson's disease. Highly complex neural implants for novel medical applications can be miniaturized either by means of precision mechanics technologies using known and established materials for electrodes, cables, and hermetic packages or by applying microsystems technologies. Examples for both approaches will be introduced and discussed. Electrode arrays for recording of electrocorticograms during presurgical epilepsy diagnosis have been manufactured using approved materials and a marking laser to achieve an integration density that is adequate in the context of brain machine interfaces, e.g. on the motor cortex. Microtechnologies have to be used for further miniaturization to develop polymer-based flexible and light weighted electrode arrays to interface the peripheral and central nervous system. Polyimide as substrate and insulation material will be discussed as well as several application examples for nerve interfaces like cuffs, filament like electrodes and large arrays for subdural implantation.

Stieglitz, Thomas; Boretius, Tim; Ordonez, Juan; Hassler, Christina; Henle, Christian; Meier, Wolfgang; Plachta, Dennis T. T.; Schuettler, Martin

2012-03-01

174

Bioengineering the skin-implant interface: the use of regenerative therapies in implanted devices.  

PubMed

This discussion and review article focuses on the possible use of regenerative techniques applied to the interfaces between skin and medical implants. As is widely known, the area of contact between an implant and the skin--the skin-implant interface--is prone to recurrent and persistent problems originated from the lack of integration between the material of the implant and the skin. Producing a long-term successful biointerface between skin and the implanted device is still an unsolved problem. These complications have prevented the development of advanced prosthetics and the evolution of biointegrated devices with new technologies. While previous techniques addressing these issues have relied mostly on the coating of the implants or the modification of the topology of the devices, recent in vitro developed techniques have shown that is possible to introduce biocompatible and possibly regenerative materials at the skin-device interface. These techniques have also shown that the process of delivering the materials has biological effects on the skin surrounding the implant, thus converting bioinert into bioactive, dynamic interfaces. Given that the best clinical outcome is the long-term stabilization and integration of the soft tissue around the implant, this article presents the basis for the selection of regenerative materials and therapies for long-term use at the skin-device interface, with focus on the use of natural biopolymers and skin cell transplantation. PMID:20140520

Peramo, Antonio; Marcelo, Cynthia L

2010-06-01

175

Benzocyclobutene (BCB) based neural implants with microfluidic channel  

Microsoft Academic Search

Benzocyclobutene (BCB) based intracortical neural implants for basic neuroscience research in animal models was fabricated, in which microfluidic channel was embedded to deliver chemical reagents. BCB presents several attractive features for chronic applications: flexibility, biocompatibility, desirable chemical and electrical properties, and can be easily manufactured using existing batch microfabrication technology; The fabricated implants have single shank with three recording sites

K. Lee; J. He; L. Wang

2004-01-01

176

Nanotechnology and Dental Implants  

PubMed Central

The long-term clinical success of dental implants is related to their early osseointegration. This paper reviews the different steps of the interactions between biological fluids, cells, tissues, and surfaces of implants. Immediately following implantation, implants are in contact with proteins and platelets from blood. The differentiation of mesenchymal stem cells will then condition the peri-implant tissue healing. Direct bone-to-implant contact is desired for a biomechanical anchoring of implants to bone rather than fibrous tissue encapsulation. Surfaces properties such as chemistry and roughness play a determinant role in these biological interactions. Physicochemical features in the nanometer range may ultimately control the adsorption of proteins as well as the adhesion and differentiation of cells. Nanotechnologies are increasingly used for surface modifications of dental implants. Another approach to enhance osseointegration is the application of thin calcium phosphate (CaP) coatings. Bioactive CaP nanocrystals deposited on titanium implants are resorbable and stimulate bone apposition and healing. Future nanometer-controlled surfaces may ultimately direct the nature of peri-implant tissues and improve their clinical success rate. PMID:21253543

Lavenus, Sandrine; Louarn, Guy; Layrolle, Pierre

2010-01-01

177

The effect of plasma chemical oxidation of titanium alloy on bone-implant contact in rats  

Microsoft Academic Search

Many different technologies have been used to enhance osseointegration in orthopaedic and dental implant surgery. Hydroxyapatite coatings, pure or in combination with growth factors or bisphosphonates, showed improved osseointegration of titanium alloy implants. We choose a different approach to enhance osseointegration: plasma chemical oxidation was used to modify the surface of titanium alloy implants. This technique converts the nm-thin natural

Michael Diefenbeck; Thomas Mückley; Christian Schrader; Jürgen Schmidt; Sergiy Zankovych; Jörg Bossert; Klaus D. Jandt; Mathilde Faucon; Ulrich Finger

2011-01-01

178

Statistical Study of Ect Detection around Fasteners Using Simulation Based Pod Curves  

NASA Astrophysics Data System (ADS)

Calculation of Probability of Detection (POD) curves based on simulation results are presented in the case of the Eddy Current Testing (ECT) configurations involving a flaw buried inside a riveted structure. In order to overcome some accuracy limitations and to optimize calculation speed, the semi-analytical model used in simulation has been improved in order to handle separate discretizations of objects. New possibilities consecutive to this development are presented, as well as two parametric models used for the computation of interactive POD curves with the CIVA software.

Reboud, C.; Pichenot, G.; Paillard, S.; Jenson, F.

2010-02-01

179

Human pre-implantation embryo development  

PubMed Central

Understanding human pre-implantation development has important implications for assisted reproductive technology (ART) and for human embryonic stem cell (hESC)-based therapies. Owing to limited resources, the cellular and molecular mechanisms governing this early stage of human development are poorly understood. Nonetheless, recent advances in non-invasive imaging techniques and molecular and genomic technologies have helped to increase our understanding of this fascinating stage of human development. Here, we summarize what is currently known about human pre-implantation embryo development and highlight how further studies of human pre-implantation embryos can be used to improve ART and to fully harness the potential of hESCs for therapeutic goals. PMID:22318624

Niakan, Kathy K.; Han, Jinnuo; Pedersen, Roger A.; Simon, Carlos; Pera, Renee A. Reijo

2012-01-01

180

Multi-Gate Fin Field-Effect Transistors Junctions Optimization by Conventional Ion Implantation for (Sub-)22 nm Technology Nodes Circuit Applications  

NASA Astrophysics Data System (ADS)

In this work we explore several doping schemes for aggressively scaled multi-gate field-effect transistor devices with the conduction channels wrapped around silicon fins (FinFETs) (HFin?37 nm, WFin?10 nm, Lg?30 nm), using conventional ion implantation (I/I), and suitable for both logic and dense circuit applications. We demonstrate that low-energy and: 1) low-tilt, double-sided extension(-less) I/I, or 2) high-tilt, single-sided extension I/I schemes can enable pitch scaling without resist shadowing effects, with no penalty in device performance and yielding higher six transistors-static random access memory (6T-SRAM) static noise margin (SNM) values. Key advantages of the extension-less approach are: reduced cost and cycle time with 2 less critical I/I photos, enabling better quality, defect-free growth of Si-epitaxial raised source/drain (SEG), and up to 20× lower IOFF. It, however, requires a tight spacer critical dimension (CD) control, a less critical parameter for the single-sided I/I scheme, which also allows wider overlay margins.

Veloso, Anabela; De Keersgieter, An; Brus, Stephan; Horiguchi, Naoto; Absil, Philippe P.; Hoffmann, Thomas

2011-04-01

181

Managing esthetic implant complications.  

PubMed

Dental implant success today is judged not only by osseointegration but also by esthetic results. Cosmetic predictability can often be difficult to attain, and esthetic implant failures can be multifactorial. Once esthetic implant failures occur, many cannot be fully corrected. Some complications must be addressed by an interdisciplinary dental team. In this summary of case reports, surgical considerations are provided, including cases of facial asymmetry/recession due to facial implant placement or bone loss resulting from technique/treatment failures, as well as papillary deficiencies. Restorative considerations for correcting failures are also discussed. PMID:22908600

Butler, Bobby; Kinzer, Greggory A

2012-01-01

182

Programming, Care, and Troubleshooting of Cochlear Implants for Children.  

ERIC Educational Resources Information Center

This article provides an overview of current cochlear implant technology, programming strategies, troubleshooting, and care techniques. It considers: device components, initial stimulation, speech coding strategies, use and care, troubleshooting, and the classroom environment. (Contains references.) (DB)

Hedley-Williams, Andrea J.; Sladen, Douglas P.; Tharpe, Anne Marie

2003-01-01

183

Master's Program Cognitive Sciences and Technologies  

E-print Network

, learning, cognitive development and cognitive breakdown, the mechanisms of reasoning, language, and problemMaster's Program Cognitive Sciences and Technologies Duration: 2 years Language of instruction: English ECTS credits: 120 Cognitive psychology is an experimental discipline in which we study the origins

Greifswald, Ernst-Moritz-Arndt-Universität

184

Additively manufactured porous tantalum implants.  

PubMed

The medical device industry's interest in open porous, metallic biomaterials has increased in response to additive manufacturing techniques enabling the production of complex shapes that cannot be produced with conventional techniques. Tantalum is an important metal for medical devices because of its good biocompatibility. In this study selective laser melting technology was used for the first time to manufacture highly porous pure tantalum implants with fully interconnected open pores. The architecture of the porous structure in combination with the material properties of tantalum result in mechanical properties close to those of human bone and allow for bone ingrowth. The bone regeneration performance of the porous tantalum was evaluated in vivo using an orthotopic load-bearing bone defect model in the rat femur. After 12weeks, substantial bone ingrowth, good quality of the regenerated bone and a strong, functional implant-bone interface connection were observed. Compared to identical porous Ti-6Al-4V structures, laser-melted tantalum shows excellent osteoconductive properties, has a higher normalized fatigue strength and allows for more plastic deformation due to its high ductility. It is therefore concluded that this is a first step towards a new generation of open porous tantalum implants manufactured using selective laser melting. PMID:25500631

Wauthle, Ruben; van der Stok, Johan; Amin Yavari, Saber; Van Humbeeck, Jan; Kruth, Jean-Pierre; Zadpoor, Amir Abbas; Weinans, Harrie; Mulier, Michiel; Schrooten, Jan

2015-03-01

185

Space Science Technology Health General Sci-fi & Gaming Oddities International Business Politics Education Entertainment Sports Implant Maps Heart Electrical Activity In  

E-print Network

current devices. The new device represents the first use of flexible silicon technology for a medical to the design of devices for localizing and treating abnormal heart rhythms. We believe these new devices in medical devices." Now, for example, devices for mapping and eliminating life-threatening heart rhythms

Rogers, John A.

186

Implant identification system.  

PubMed

Osseointegrated oral implantology has become a widespread option of dental care. A universal system of implant identification is required to enable dentists, patients and participating third parties to accurately identify a particular implant and historically record and follow its bio-clinical status. A simple system, based on the existing FDI two-digit tooth identification system is presented. PMID:10858743

Colgan, P J

1999-04-01

187

Implantable CMOS Biomedical Devices  

PubMed Central

The results of recent research on our implantable CMOS biomedical devices are reviewed. Topics include retinal prosthesis devices and deep-brain implantation devices for small animals. Fundamental device structures and characteristics as well as in vivo experiments are presented. PMID:22291554

Ohta, Jun; Tokuda, Takashi; Sasagawa, Kiyotaka; Noda, Toshihiko

2009-01-01

188

Batteryless implanted echosonometer  

NASA Technical Reports Server (NTRS)

Miniature ultrasonic echosonometer implanted within laboratory animals obtains energy from RF power oscillator that is electronically transduced via induction loop to power receiving loop located just under animal's skin. Method of powering device offers significant advantages over those in which battery is part of implanted package.

Kojima, G. K.

1977-01-01

189

Graphene for Biomedical Implants  

NASA Astrophysics Data System (ADS)

In this study, we used graphene, a one-atom thick sheet of carbon atoms, to modify the surfaces of existing implant materials to enhance both bio- and hemo-compatibility. This novel effort meets all functional criteria for a biomedical implant coating as it is chemically inert, atomically smooth and highly durable, with the potential for greatly enhancing the effectiveness of such implants. Specifically, graphene coatings on nitinol, a widely used implant and stent material, showed that graphene coated nitinol (Gr-NiTi) supports excellent smooth muscle and endothelial cell growth leading to better cell proliferation. We further determined that the serum albumin adsorption on Gr-NiTi is greater than that of fibrinogen, an important and well understood criterion for promoting a lower thrombosis rate. These hemo-and biocompatible properties and associated charge transfer mechanisms, along with high strength, chemical inertness and durability give graphene an edge over most antithrombogenic coatings for biomedical implants and devices.

Moore, Thomas; Podila, Ramakrishna; Alexis, Frank; Rao, Apparao

2013-03-01

190

Nucleotide exchange factor ECT2 interacts with the polarity protein complex Par6/Par3/protein kinase Czeta (PKCzeta) and regulates PKCzeta activity.  

PubMed

Regulation of cell polarity is an important biological event that governs diverse cell functions such as localization of embryonic determinants and establishment of tissue and organ architecture. The Rho family GTPases and the polarity complex Par6/Par3/atypical protein kinase C (PKC) play a key role in the signaling pathway, but the molecules that regulate upstream signaling are still not known. Here we identified the guanine nucleotide exchange factor ECT2 as an activator of the polarity complex. ECT2 interacted with Par6 as well as Par3 and PKCzeta. Coexpression of Par6 and ECT2 efficiently activated Cdc42 in vivo. Overexpression of ECT2 also stimulated the PKCzeta activity, whereas dominant-negative ECT2 inhibited the increase in PKCzeta activity stimulated by Par6. ECT2 localization was detected at sites of cell-cell contact as well as in the nucleus of MDCK cells. The expression and localization of ECT2 were regulated by calcium, which is a critical regulator of cell-cell adhesion. Together, these results suggest that ECT2 regulates the polarity complex Par6/Par3/PKCzeta and possibly plays a role in epithelial cell polarity. PMID:15254234

Liu, Xiu-Fen; Ishida, Hiroshi; Raziuddin, Razi; Miki, Toru

2004-08-01

191

Focal Electrically Administered Seizure Therapy: A Novel form of ECT Illustrates the Roles of Current Directionality, Polarity, and Electrode Configuration in Seizure Induction  

Microsoft Academic Search

Electroconvulsive therapy (ECT) is a mainstay in the treatment of severe, medication-resistant depression. The antidepressant efficacy and cognitive side effects of ECT are influenced by the position of the electrodes on the head and by the degree to which the electrical stimulus exceeds the threshold for seizure induction. However, surprisingly little is known about the effects of other key electrical

Timothy Spellman; Angel V Peterchev; Sarah H Lisanby

2009-01-01

192

Effectiveness and clinical predictors of response to combined ECT and antipsychotic therapy in patients with treatment-resistant schizophrenia and dominant negative symptoms.  

PubMed

The effectiveness and predictors of response to electroconvulsive therapy (ECT) combined with antipsychotics (AP) in treatment-resistant schizophrenia patients with the dominance of negative symptoms (TRS-NS) have not been studied systematically so far. 29 patients aged 21-55 years diagnosed with TRS-NS underwent ECT combined with antipsychotics (ECT+AP). Prior to the ECT, the symptom profile and severity were evaluated using Positive and Negative Syndrome Scale (PANSS). Demographic and medical data was collected; ECT parameters and pharmacotherapy results were evaluated. After the combined ECT+AP therapy a significant decrease in symptom severity was found. A response to treatment was achieved by 60% of patients. The greatest reductions were obtained in general and positive PANSS subscale (median change: 11 and 7 pts.) and the smallest, but still significant, ones in negative symptoms subscale (median: 3.5 pts.). Patients who responded to ECT+AP demonstrated a significantly shorter duration of the current episode in comparison with patients who did not experience at least a 25% reduction in symptom severity (median: 4 vs. 8 months). A combination of ECT and antipsychotic therapy can provide a useful treatment option for patients with TRS-NS. The only significant predictor of response to treatment was a shorter duration of the current episode. PMID:25129562

Pawe?czyk, Tomasz; Ko?odziej-Kowalska, Emilia; Pawe?czyk, Agnieszka; Rabe-Jab?o?ska, Jolanta

2014-12-15

193

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. Module A: Fundamentals of Marine Biology and Ecology (15 ECTS) Modul  

E-print Network

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. Module A: Fundamentals of Marine Biology and Ecology Biology and Biological Oceanography Principles of Marine Ecophysiology Experimental Design & Data Analysis: Advanced Studies in Marine Biology (18 ECTS) Module G: Project Development & Implementation (9 ECTS

Hoffmeister, Thomas S.

194

Medical application of ion implantation (Ionguard TM) for overall improvement of titanium alloys  

NASA Astrophysics Data System (ADS)

Ion implantation is an emerging technology that allows for selective modification of the surface properties of materials. Properties such as hardness, corrosion resistance, friction and others can be improved without adversely affecting the bulk properties of the material. This paper concentrates on the discussion of the overall improvement of orthopaedic implants by the ion implantation (IONGUARD TM) process. The unique capabilities, outstanding features and overall potential of the technology are described. Based on the very impressive improvement in wear, corrosion and fatigue resistance, the ion implantation process is expected to become the technology of choice not only for surface treatment of titanium orthopaedic implants but also in other medical applications such as titanium surgical scissors or dental implants. The technology is also expected to have an increasing contribution in a great variety of other applications such as the aerospace field.

Sioshansi, Piran

1987-04-01

195

Maximizing cochlear implant patients' performance with advanced speech training procedures.  

PubMed

Advances in implant technology and speech processing have provided great benefit to many cochlear implant patients. However, some patients receive little benefit from the latest technology, even after many years' experience with the device. Moreover, even the best cochlear implant performers have great difficulty understanding speech in background noise, and music perception and appreciation remain major challenges. Recent studies have shown that targeted auditory training can significantly improve cochlear implant patients' speech recognition performance. Such benefits are not only observed in poorly performing patients, but also in good performers under difficult listening conditions (e.g., speech noise, telephone speech, music, etc.). Targeted auditory training has also been shown to enhance performance gains provided by new implant devices and/or speech processing strategies. These studies suggest that cochlear implantation alone may not fully meet the needs of many patients, and that additional auditory rehabilitation may be needed to maximize the benefits of the implant device. Continuing research will aid in the development of efficient and effective training protocols and materials, thereby minimizing the costs (in terms of time, effort and resources) associated with auditory rehabilitation while maximizing the benefits of cochlear implantation for all recipients. PMID:18295992

Fu, Qian-Jie; Galvin, John J

2008-08-01

196

Implantable brain computer interface: challenges to neurotechnology translation.  

PubMed

This article reviews three concepts related to implantable brain computer interface (BCI) devices being designed for human use: neural signal extraction primarily for motor commands, signal insertion to restore sensation, and technological challenges that remain. A significant body of literature has occurred over the past four decades regarding motor cortex signal extraction for upper extremity movement or computer interface. However, little is discussed regarding postural or ambulation command signaling. Auditory prosthesis research continues to represent the majority of literature on BCI signal insertion. Significant hurdles continue in the technological translation of BCI implants. These include developing a stable neural interface, significantly increasing signal processing capabilities, and methods of data transfer throughout the human body. The past few years, however, have provided extraordinary human examples of BCI implant potential. Despite technological hurdles, proof-of-concept animal and human studies provide significant encouragement that BCI implants may well find their way into mainstream medical practice in the foreseeable future. PMID:20035870

Konrad, Peter; Shanks, Todd

2010-06-01

197

Technology.  

ERIC Educational Resources Information Center

Focuses on technology, on advances in such areas as aeronautics, electronics, physics, the space sciences, as well as computers and the attendant progress in medicine, robotics, and artificial intelligence. Describes educational resources for elementary and middle school students, including Web sites, CD-ROMs and software, videotapes, books,…

Online-Offline, 1998

1998-01-01

198

Mobility implants: a review.  

PubMed

We present a brief review of mobility implants, their contribution, and the experiences derived after almost 40 years since the new concepts of full mobility implants were introduced. In early 1940, experiments with a new material for the making of plastic artificial eyes was also being considered for the making of orbital implants. Methyl-methacrylate (MMA) had proven inert and satisfactory for dental products. The Surgeon Generals office of the Armed Services encouraged further research and experimental work in the development of plastic eyes. The success of the new material sponsored the beginning of great expansion with new concepts for orbital implants. Through a period of more than a decade, the design and types of implants went through three stages. First, the buried implant was introduced, then the exposed integrated followed, and the buried integrated subsequently followed. The path of progress was not smooth. Theoretically correct designs and surgical procedures met unexpected practical difficulties for the ophthalmic surgeon, the patient, and the eye maker. Surgical and technical efforts were carefully reviewed to eliminate the problems encountered, only to have further unforeseen complications arise. Infections, extrusions, and migration of the implant were not uncommon. The exposed integrated implant was eventually abandoned. However, there were some extraordinary successes of mobility. A new era introduced fully buried mobility implants that were more successful. However, this procedure also produced some problems, causing infection (or allergy), extrusion, and migration. Tantalum mesh and gauze gave great promise with the inception of their use. Orbital tissue grew into the material in an astonishing way, making it possible to secure the extraocular muscles and tenons.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2248721

Danz, W

1990-01-01

199

Monte Carlo Study of the E ects of Design Parameters on the Sensitivity of a CMB Polarization Experiment  

E-print Network

Monte Carlo Study of the E#11;ects of Design Parameters on the Sensitivity of a CMB Polarization a monte carlo to simulate Cosmic Microwave Background polarization maps on caps around the North Celestial Pole. We used this monte carlo to explore how the sensitivity of a single parameter #12;t depends

200

Antidepressant efficacy of Sudarshan Kriya Yoga (SKY) in melancholia: a randomized comparison with electroconvulsive therapy (ECT) and imipramine  

Microsoft Academic Search

Background: Sudarshan Kriya Yoga (SKY) is a procedure that involves essentially rhythmic hyperventilation at different rates of breathing. The antidepressant efficacy of SKY was demonstrated in dysthymia in a prospective, open clinical trial. This study compared the relative antidepressant efficacy of SKY in melancholia with two of the current standard treatments, electroconvulsive therapy (ECT) and imipramine (IMN). Methods: Consenting, untreated

N. Janakiramaiah; B. N. Gangadhar; P. J. Naga Venkatesha Murthy; M. G. Harish; D. K. Subbakrishna; A. Vedamurthachar

2000-01-01

201

Continental Shelf Research 20 (2000) 1}13 Internal tide e!ects on a sewage plume  

E-print Network

Continental Shelf Research 20 (2000) 1}13 Internal tide e!ects on a sewage plume at Sand Island, is described and explained by the forcing from an internal tide. The sewage plume, discharged from the Sand to the di!user, suggested that the presence of an internal tide of 18 km wavelength propagating along

Fabrikant, Sara Irina

202

ePUB: Modellierung Molecular Life Sciences Master Major 90 ECTS-Credits with special qualification in Biochemistry/  

E-print Network

in Biochemistry/ Chemical Biology [Reglement 01.10.2005] Seite 1 1. Teil: Struktur des Studiums (Prüfungsfächer) Offizieller Abschluss: Master of Science in Molecular Life Sciences with special qualification in Biochemistry/Chemical Biology, Universität Bern ePUB - interne Bezeichnung: MLS M Major 90 ECTS Biochemistry/Chemical Biology

Richner, Heinz

203

ePUB: Modellierung Molecular Life Sciences Master Major 90 ECTS-Credits with special qualification in Plant Physiology  

E-print Network

in Plant Physiology [Reglement 01.10.2005] Seite 1 1. Teil: Struktur des Studiums (Prüfungsfächer Physiology, Universität Bern ePUB - interne Bezeichnung: MLS M Major 90 ECTS Plant Physiology [MLSMA Module general topics Module special qualification Plant Physiology 2. Teil: Struktur der Leistungen

Richner, Heinz

204

Transcatheter aortic valve implantation  

PubMed Central

Transcatheter aortic valve implantation was developed to offer a therapeutic solution to patients with severe symptomatic aortic stenosis who are not candidates for conventional aortic valve replacement. The improvement in transcatheter aortic valve implantation outcomes is still of concern in the areas of stroke, vascular injury, heart block, paravalvular regurgitation and valve durability. Concomitantly, the progress, both technical and in terms of material advances of transcatheter valve systems, as well as in patient selection, renders transcatheter aortic valve implantation an increasingly viable treatment for more and more patients with structural heart disease. PMID:25374670

Oliemy, Ahmed

2014-01-01

205

Biological Functionalization of Dental Implants with Fibronectin: A Scanning Electron Microscopic Study  

PubMed Central

Objectives Early stages of peri-implant bone formation play an essential role in the osseointegration and long-term success of dental implants. Biological implant surface coatings are an emerging technology to enhance the attachment of the implant to the surrounding bone and stimulate bone regeneration. The purpose of this study was to determine the effect of coating the implant surface with fibronectin on osseointegration. Material and methods The experiment was conducted on a total of twelve New Zealand white mature male rabbits, weight between 2.5–4 kg. Twenty four pure titanium implants were used in this study. Each rabbits received two implants, one implant in each tibia; the implant in the right limb was coated with fibronectin (experimental group), whilst on the contralateral side the implants were placed without coating (control group). Six rabbits were sacrificed for Scanning Electron Microscopic evaluation after 4 and 8 week healing periods. Results The results of the present study demonstrating the mean gap distance between the bone and implant was greater in the control group compared to fibronection group at both observation periods however, the difference between these two groups was not statistically significant. Conclusion Thus, it could be suggested that the biological functionalization of dental implants with fibronectin, may influence the integration or biocompatibility and bonding of the implant to the surrounding bone. PMID:24899880

Elkarargy, Amr

2014-01-01

206

A touch probe method of operating an implantable RFID tag for orthopedic implant identification.  

PubMed

The major problem in operating an implantable radio-frequency identification (RFID) tag embedded on an orthopedic implant is low efficiency because of metallic interference. To improve the efficiency, this paper proposes a method of operating an implantable passive RFID tag using a touch probe at 13.56 MHz. This technology relies on the electric field interaction between two pairs of electrodes, one being a part of the touch probe placed on the surface of tissue and the other being a part of the tag installed under the tissue. Compared with using a conventional RFID antenna such as a loop antenna, this method has a better performance in the near field operation range to reduce interference with the orthopedic implant. Properly matching the touch probe and the tag to the tissue and the implant reduces signal attenuation and increases the overall system efficiency. The experiments have shown that this method has a great performance in the near field transcutaneous operation and can be used for orthopedic implant identification. PMID:23853323

Liu, Xiaoyu; Berger, J Lee; Ogirala, Ajay; Mickle, Marlin H

2013-06-01

207

Wrapping hydroxyapatite implants.  

PubMed

Hydroxyapatite (HA) implants currently are most commonly wrapped in fresh unprocessed human donor sclera before implantation to facilitate entry into the orbital space and allow extraocular muscle attachment. Autologous temporalis fascia or autologous fascia lata are alternatives, but prolong surgery time and require a second operative site. Recently, a number of other wraps, such as processed human pericardium, processed human fascia lata, processed human sclera, bovine pericardium and expanded polytetrafluoroethylene [e-PTFE], have being marketed. Although they also facilitate implant placement, they can be costly. Polygalactin (Vicryl, Ethicon, Somerville, NJ) mesh is another readily available wrap that is easy to use and cost effective. To obtain a high success rate with this wrap, the polygalactin mesh wrapped HA implant must be moistened and seated into the orbit properly. If it is not, exposure may occur, which may explain why some surgeons shy away from its use. The proper technique is reviewed in this paper. PMID:10334031

Jordan, D R; Klapper, S R

1999-05-01

208

Risks of Breast Implants  

MedlinePLUS

... a 29-year- old woman 7 years after placement of silicone gel-filled breast implants. Photo courtesy ... stresses such as trauma or intense physical pressure Placement through a non-FDA approved incision site, for ...

209

Visible Embryo: Implantation begins  

NSDL National Science Digital Library

the page on early implantation and HCG production from a comprehensive resource of information on human development from conception to birth, designed for both medical student and interested lay people.

Carmen Arbona (Mouseworks)

2006-09-08

210

Corrosion of bio implants  

Microsoft Academic Search

Chemical stability, mechanical behaviour and biocompatibility in body fluids and tissues are the basic requirements for successful\\u000a application of implant materials in bone fractures and replacements. Corrosion is one of the major processes affecting the\\u000a life and service of orthopaedic devices made of metals and alloys used as implants in the body. Among the metals and alloys\\u000a known, stainless steels

U. Kamachimudali; T. M. Sridhar; Baldev Raj

2003-01-01

211

Microtelemetry techniques for implantable smart sensors  

NASA Astrophysics Data System (ADS)

The advent of the emerging field of smart sensors suggests new applications for implantable microelectronic devices in neural prostheses. Optimal use of miniature and subminiature (thin- film) electronic sensors in implanted systems will depend upon the nature of the power and communication link to the sensor. Microtelemetry technology is under current development to meet this need. Microtelemetry techniques can be used to provide operating power and bi- directional communication for a microimplant through a common, wireless, magnetic link. Owing to the extremely unfavorable geometry, i.e. the size of the implant relative to the size of the extracorporeal transmitter, the design of such links is highly parametric. Magnetic circuit parameters must be closely matched to the implant's integrated-circuit power usage. In addition, the bandwidth of the communication channel must be adequate to meet the data collection requirements. This paper describes on-going R&D work for the design and fabrication of smart sensors based upon microtelemetry technology. Presently, sensor designs for two applications are in progress -- EMG and joint angle position.

Troyk, Philip R.; Schwan, M. A.; DeMichele, G. A.; Loeb, Gerald E.; Schulman, Joe; Strojnik, P.

1996-05-01

212

The Biolink Implantable Telemetry System  

NASA Technical Reports Server (NTRS)

Most biotelemetry applications deal with the moderated data rates of biological signals. Few people have studied the problem of transcutaneous data transmission at the rates required by NASA's Life Sciences-Advanced BioTelemetry System (LS-ABTS). Implanted telemetry eliminate the problems associated with wire breaking the skin, and permits experiments with awake and unrestrained subjects. Our goal is to build a low-power 174-216MHz Radio Frequency (RF) transmitter suitable for short range biosensor and implantable use. The BioLink Implantable Telemetry System (BITS) is composed of three major units: an Analog Data Module (ADM), a Telemetry Transmitter Module (TTM), and a Command Receiver Module (CRM). BioLink incorporates novel low-power techniques to implement a monolithic digital RF transmitter operating at 100kbps, using quadrature phase shift keying (QPSK) modulation in the 174-216MHz ISM band. As the ADM will be specific for each application, we focused on solving the problems associated with a monolithic implementation of the TTM and CRM, and this is the emphasis of this report. A system architecture based on a Frequency-Locked Loop (FLL) Frequency Synthesizer is presented, and a novel differential frequency that eliminates the need for a frequency divider is also shown. A self sizing phase modulation scheme suitable for low power implementation was also developed. A full system-level simulation of the FLL was performed and loop filter parameters were determined. The implantable antenna has been designed, simulated and constructed. An implant package compatible with the ABTS requirements is also being proposed. Extensive work performed at 200MHz in 0.5um complementary metal oxide semiconductors (CMOS) showed the feasibility of integrating the RF transmitter circuits in a single chip. The Hajimiri phase noise model was used to optimize the Voltage Controlled Oscillator (VCO) for minimum power consumption. Two test chips were fabricated in a 0.5pm, 3V CMOS process. Measured phase noise for a 1.5mW, 200MHz ring oscillator VCO is -80dBc/Hz at 100KHZ offset, showing good agreement with the theory. We also propose a novel superregenerative receiver architecture for implementing the command receiver. The superregenerative receiver's simplicity, low cost, and low power consumption has made it the receiver of choice for short-distance data communications, remote control and home automation. We present the design of a superregenerative AM receiver implemented in a 0.5um CMOS technology that operates at 433.92MHz and dissipates only 300uW. Further work entails detailed transistor-level design of the FLL and superregenerative receiver and a monolithic implementation of an implantable transceiver in 0.5um CMOS technology.

Betancourt-Zamora, Rafael J.

1999-01-01

213

Effects of urinary and recombinant gonadotrophins on gene expression profiles during the murine peri-implantation period  

Microsoft Academic Search

BACKGROUND: Controlled ovarian stimulation (COS) with urinary gonadotrophins but not recombinant gonado- trophins, adversely affect the implantation process. In this study, we investigated the effects of urinary and recom- binant gonadotrophins on gene expression profiles at implantation sites during the mouse peri-implantation period and the possible molecular mechanisms involved in the detrimental effects of urinary gonadotrophins using microar- ray technology.

R. M. Sibug; N. Datson; A. M. I. Tijssen; M. Morsink; J. de Koning; E. R. de Kloet; F. M. Helmerhorst

2006-01-01

214

Implant-bone interface characteristics of bioglass dental implants.  

PubMed

Three-dimensional finite element analysis (FEA) has been used to determine the implant-bone interface characteristics of bioglass dental implants. The results of the FEA were verified by comparison with the results of mechanical testing performed on animal implant specimens. The results of the study showed that the assumption of a discontinuous change of elastic properties at the bone-implant interface was a poor assumption for the bioglass implants. Interface elastic moduli of 354.0, 155.0, and 47.0 MPa for conditions of 25, 50, and 100% tissue attachment were determined for the bioglass implants. PMID:6987233

Weinstein, A M; Klawitter, J J; Cook, S D

1980-01-01

215

Maxillary overdentures supported by four splinted direct metal laser sintering implants: a 3-year prospective clinical study.  

PubMed

Purpose. Nowadays, the advancements in direct metal laser sintering (DMLS) technology allow the fabrication of titanium dental implants. The aim of this study was to evaluate implant survival, complications, and peri-implant marginal bone loss of DMLS implants used to support bar-retained maxillary overdentures. Materials and Methods. Over a 2-year period, 120 implants were placed in the maxilla of 30 patients (18 males, 12 females) to support bar-retained maxillary overdentures (ODs). Each OD was supported by 4 implants splinted by a rigid cobalt-chrome bar. At each annual follow-up session, clinical and radiographic parameters were assessed. The outcome measures were implant failure, biological and prosthetic complications, and peri-implant marginal bone loss (distance between the implant shoulder and the first visible bone-to-implant contact, DIB). Results. The 3-year implant survival rate was 97.4% (implant-based) and 92.9% (patient-based). Three implants failed. The incidence of biological complication was 3.5% (implant-based) and 7.1% (patient-based). The incidence of prosthetic complication was 17.8% (patient-based). No detrimental effects on marginal bone level were evidenced. Conclusions. The use of 4 DMLS titanium implants to support bar-retained maxillary ODs seems to represent a safe and successful procedure. Long-term clinical studies on a larger sample of patients are needed to confirm these results. PMID:25580124

Mangano, Francesco; Luongo, Fabrizia; Shibli, Jamil Awad; Anil, Sukumaran; Mangano, Carlo

2014-01-01

216

Maxillary Overdentures Supported by Four Splinted Direct Metal Laser Sintering Implants: A 3-Year Prospective Clinical Study  

PubMed Central

Purpose. Nowadays, the advancements in direct metal laser sintering (DMLS) technology allow the fabrication of titanium dental implants. The aim of this study was to evaluate implant survival, complications, and peri-implant marginal bone loss of DMLS implants used to support bar-retained maxillary overdentures. Materials and Methods. Over a 2-year period, 120 implants were placed in the maxilla of 30 patients (18 males, 12 females) to support bar-retained maxillary overdentures (ODs). Each OD was supported by 4 implants splinted by a rigid cobalt-chrome bar. At each annual follow-up session, clinical and radiographic parameters were assessed. The outcome measures were implant failure, biological and prosthetic complications, and peri-implant marginal bone loss (distance between the implant shoulder and the first visible bone-to-implant contact, DIB). Results. The 3-year implant survival rate was 97.4% (implant-based) and 92.9% (patient-based). Three implants failed. The incidence of biological complication was 3.5% (implant-based) and 7.1% (patient-based). The incidence of prosthetic complication was 17.8% (patient-based). No detrimental effects on marginal bone level were evidenced. Conclusions. The use of 4 DMLS titanium implants to support bar-retained maxillary ODs seems to represent a safe and successful procedure. Long-term clinical studies on a larger sample of patients are needed to confirm these results. PMID:25580124

Mangano, Francesco; Shibli, Jamil Awad; Anil, Sukumaran

2014-01-01

217

Identification and characterization of ectoine biosynthesis genes and heterologous expression of the ectABC gene cluster from Halomonas sp. QHL1, a moderately halophilic bacterium isolated from Qinghai Lake.  

PubMed

The moderately halophilic bacterium Halomonas sp. QHL1 was identified as a member of the genus Halomonas by 16S rRNA gene sequencing. HPLC analysis showed that strain QHL1 synthesizes ectoine in its cytoplasm. The genes involved in the ectoine biosynthesis pathway were identified on the chromosome in the order ectABC. Subsequently, the ectB gene from this strain was amplified by PCR, and the entire ectABC gene cluster (3,580 bp) was cloned using genome walking. Analysis showed that the ectA (579 bp), ectB (1269 bp), and ectC (390 bp) genes were organized in a single transcriptional unit and were predicted to encode three peptides of 21.2 kDa, 46.4 kDa, and 14.7 kDa, respectively. Two putative promoters, a ?(70)-dependent promoter and a ?(38)-controlled promoter, as well as several conserved motifs with unknown function were identified. Individual ectA, ectB, and ectC genes, and the entire ectABC gene cluster were inserted into the expression plasmid pET-28a(+) to generate the recombinant plasmids pET-28a(+)-ectA, pET-28a(+)-ectB, pET-28a(+)-ectC and pET-28a(+)-ectABC, respectively. Heterologous expression of these proteins in Escherichia coli BL21 (DE3) was confirmed by SDS-PAGE. The recombinant E. coli strain BL21 (pET-28a (+)-ectABC) displayed a higher salt tolerance than native E. coli cells but produced far less ectoine than the wild-type QHL1 strain. PMID:24500478

Zhu, Derui; Liu, Jian; Han, Rui; Shen, Guoping; Long, Qifu; Wei, Xiaoxing; Liu, Deli

2014-02-01

218

Ethical implications of implantable radiofrequency identification (RFID) tags in humans.  

PubMed

This article reviews the use of implantable radiofrequency identification (RFID) tags in humans, focusing on the VeriChip (VeriChip Corporation, Delray Beach, FL) and the associated VeriMed patient identification system. In addition, various nonmedical applications for implanted RFID tags in humans have been proposed. The technology offers important health and nonhealth benefits, but raises ethical concerns, including privacy and the potential for coercive implantation of RFID tags in individuals. A national discussion is needed to identify the limits of acceptable use of implantable RFID tags in humans before their use becomes widespread and it becomes too late to prevent misuse of this useful but ethically problematic technology. PMID:18802863

Foster, Kenneth R; Jaeger, Jan

2008-08-01

219

Modulation Techniques for Biomedical Implanted Devices and Their Challenges  

PubMed Central

Implanted medical devices are very important electronic devices because of their usefulness in monitoring and diagnosis, safety and comfort for patients. Since 1950s, remarkable efforts have been undertaken for the development of bio-medical implanted and wireless telemetry bio-devices. Issues such as design of suitable modulation methods, use of power and monitoring devices, transfer energy from external to internal parts with high efficiency and high data rates and low power consumption all play an important role in the development of implantable devices. This paper provides a comprehensive survey on various modulation and demodulation techniques such as amplitude shift keying (ASK), frequency shift keying (FSK) and phase shift keying (PSK) of the existing wireless implanted devices. The details of specifications, including carrier frequency, CMOS size, data rate, power consumption and supply, chip area and application of the various modulation schemes of the implanted devices are investigated and summarized in the tables along with the corresponding key references. Current challenges and problems of the typical modulation applications of these technologies are illustrated with a brief suggestions and discussion for the progress of implanted device research in the future. It is observed that the prime requisites for the good quality of the implanted devices and their reliability are the energy transformation, data rate, CMOS size, power consumption and operation frequency. This review will hopefully lead to increasing efforts towards the development of low powered, high efficient, high data rate and reliable implanted devices. PMID:22368470

Hannan, Mahammad A.; Abbas, Saad M.; Samad, Salina A.; Hussain, Aini

2012-01-01

220

A decaborane ion source for high current implantation  

NASA Astrophysics Data System (ADS)

Progressive semiconductor device scaling in each technology node requires the formation of shallower junctions, and thus lower energy implants. The difficulties associated with extraction and transport of low energy beams often result in a loss in wafer throughput. Implantation of boron using the molecular compound decaborane has been found to allow for the shallow implantation of boron without a significant design change in the implanter. The decaborane molecule has 10 boron atoms and 14 hydrogen atoms. The implanted dose is ten times the electrical dose and the implanted depth is equivalent to the depth of a boron beam at 1/11th of the extraction energy. This advantage can only be exploited with an ion source that does not destroy the fragile molecule. We report on the design of an ion source capable of ionizing decaborane without significant fragmentation of the molecule. After it was shown that the decaborane molecule fragments above 350 °C an ion source was designed to prevent thermal dissociation of the molecule. Competitive boron dose rates were achieved using this source in a commercial high current implanter. In addition, evidence is shown that a decaborane dimer is formed in the ion source and can be implanted.

Perel, Alex S.; Loizides, William K.; Reynolds, William E.

2002-02-01

221

Bone growth around dental implants.  

PubMed

For the complete understanding of stimulation of bone growth around dental implants, a thorough knowledge is necessary regarding the reaction of bone to trauma and to a variety of implant materials. The atraumatic preparation of the bony implant bed serves to create the most favorable situation for the formation of bone around any implant material. Some implant materials are more likely to result in soft tissue encapsulation despite the most careful handling of bone; others result in different amounts of implant-bone contact zones. From the character and the amount of bone formation around different implants, it can be concluded whether the used materials are biocompatible. Titanium-surfaced implants may not demonstrate the biocompatibility that is seen with hydroxyapatite-coated implants. However, the results seen with hydroxyapatite-coated implants have to be viewed critically because the biointegrity of these coatings has not been demonstrated until now. On the other hand, titanium-surfaced implants have success rates for as long as 25 years and enable the implantologist to rely on a well-accepted implant material. The use of guided tissue regeneration and the sinus augmentation technique appear to enable the implantologist to stimulate bone formation around dental implants. These techniques may extend the limits for the successful placement of dental implants into bone-deficient sites. PMID:1879579

Weinlaender, M

1991-07-01

222

Biological fixation of endosseous implants.  

PubMed

Primary implant stability is ensured by a mechanical fixation of implants. However, during implant healing a biological anchorage is necessary to achieve final osseointegration. Aim of this study was to investigate the histological aspects of biological fixation around titanium screws. Forty-eight titanium screws with different surfaces (smooth, plasma sprayed, sand blasted) were inserted in tibiae and femura of sheep and analyzed by light microscope and SEM 1 hour, 14 and 90 days after implantation. One hour after implantation the implant-bone gap was filled with a blood clot and host bone chips arising from burr surgical preparation or friction during implant insertion. Fourteen days after implantation new trabecular bone and enveloped bone chips were observed in the gap: no osteogenesis developed where implant threads were in contact with host bone. Ninety days after surgery all trabecular bone and most of the bone chips were substituted by a mature lamellar bone with few marrow spaces. Our results suggest that the trabecular bone and bone chips represent a three-dimensional network ensuring a biological implant fixation in all different implant surfaces 2 weeks after surgery. Host bone chips could favour the peri-implant osteogenesis. Inter-trabecular and implant-trabecular marrow spaces of both trabecular and lamellar bone may favour the peri-implant bone turnover. PMID:16233979

Franchi, M; Fini, M; Martini, D; Orsini, E; Leonardi, L; Ruggeri, A; Giavaresi, G; Ottani, V

2005-01-01

223

Implanted p+n-Junctions in Silicon Carbide  

Microsoft Academic Search

Ion implantation is considered a key technology for the realisation of silicon carbide electronic devices. Here we will give an overview of the field and present some recent results of ion implanted 4H SiC epitaxial layers. Mainly Al ions of keV energies have been used at different fluence, flux and target temperature. The samples have been investigated by secondary ion

A. Hallén; M. S. Janson; J. Osterman; U. Zimmermann; M. Linnarsson; A. Kuznetsov; Y. Zhang; B. G. Svensson

2003-01-01

224

Laser Additive Manufacturing of Modified Implant Surfaces with Osseointegrative Characteristics  

Microsoft Academic Search

Additive Manufacturing technology, such as Selective Laser Melting, allows fabrication of complex metal parts with freeform surfaces. Using biocompatible metal alloys, e.g. TiAl6V4, medical implants can be produced. To increase osseointegrative behavior the ability to fabricate filigree lattice structures can be utilized to achieve a modified implant surface. In order to increase dimensional accuracy when applying a lattice structure on

C. Emmelmann; P. Scheinemann; M. Munsch; V. Seyda

2011-01-01

225

Effectiveness of implantation of a subcutaneous implantable cardioverter-defibrillator in a patient with complete heart block and a pacemaker.  

PubMed

The subcutaneous implantable cardioverter-defibrillator (S-ICD) represents an important alternative to traditional ICD therapy. The major limitation of this technology is the inability to provide pacing. Here, we present a case of a patient with complete heart block and a pacemaker who underwent placement of an S-ICD. Special considerations had to be taken with regards to evaluation and implantation of the S-ICD because of the pacemaker. In conclusion, implantation of an S-ICD can be done in patients with pacemaker effectively with appropriate electrocardiographic screening, device testing, and programming. PMID:25465940

Porterfield, Christopher; DiMarco, John P; Mason, Pamela K

2015-01-15

226

Age at implantation and auditory memory in cochlear implanted children.  

PubMed

Early cochlear implantation, before the age of 3 years, provides the best outcome regarding listening, speech, cognition an memory due to maximal central nervous system plasticity. Intensive postoperative training improves not only auditory performance and language, but affects auditory memory as well. The aim of this study was to discover if the age at implantation affects auditory memory function in cochlear implanted children. A total of 50 cochlear implanted children aged 4 to 8 years were enrolled in this study: early implanted (1-3y) n = 27 and late implanted (4-6y) n = 23. Two types of memory tests were used: Immediate Verbal Memory Test and Forward and Backward Digit Span Test. Early implanted children performed better on both verbal and numeric tasks of auditory memory. The difference was statistically significant, especially on the complex tasks. Early cochlear implantation, before the age of 3 years, significantly improve auditory memory and contribute to better cognitive and education outcomes. PMID:24869438

Mikic, B; Miric, D; Nikolic-Mikic, M; Ostojic, S; Asanovic, M

2014-05-01

227

MEAT SCIENCE AND MUSCLE BIOLOGY SYMPOSIUM--anabolic implants and meat quality.  

PubMed

Anabolic implants are routinely used in the finishing phase of beef production to improve animal performance and feed efficiency. Implanting during the feedlot phase on average increases ADG 18%, feed intake 6%, feed efficiency 8%, carcass weight 5%, and ribeye area 4% compared with nonimplanted controls. Implants reduce the cost of beef production, which is important given current high feed costs and beef prices. In a 1996 review of 37 implant trials, the use of a combination (i.e., estrogenic and trenbolone acetate) implant increased returns by US$77/head compared with nonimplanted steers. If calculated using today's prices, a combination implant would increase returns by $163/head. However, concerns about potential negative effects of implants on marbling scores, quality grades, and tenderness exist. Changes in Warner-Bratzler shear force values of steaks from implanted steers are small (<0.5 kg) and appear related to an increase in initial tenderness, possibly due to hypertrophy of muscle fiber, instead of alterations in postmortem proteolysis. The increase in ribeye size observed with implanting may also reduce marbling scores through a dilution effect. The impact of anabolic implants on gene expression has shown that implanting downregulates expression of certain lipogenic genes (e.g., stearoyl-CoA desaturase, fatty acid synthetase, fatty acid elongase-6) in steers with low quality grades (Select-) but not in implanted steers with high quality grades (Choice-). Examination of the adipocyte's transcriptome has shown that 36 genes were differentially expressed due to implant treatment. More research is needed to further determine how anabolic implants alter lipogenic gene expression to address changes in marbling deposition with implant usage. Given our current high feed costs and cattle prices, anabolic implants are one of the most cost-effective technologies that can be used in beef production systems. PMID:24243897

Duckett, S K; Pratt, S L

2014-01-01

228

Radome technology  

NASA Astrophysics Data System (ADS)

The paper gives a comprehensive view of the manifold field of radome technology, specifies the parameters influencing the choice of materials and the structural design of advanced aircraft radomes, and deals with the technical disciplines contributing to radome technology. In this connection, recently developed computational methods, materials and manufacturing techniques, as well as test procedures and test facilities, are considered. The wide ranging application of radome technology is outlined. The strong connection between radome materials and materials for medical implant and the fruitful interaction between rain erosion testing and shock wave research for medical applications are described.

Natter, Manfred; Schroeder, Hans-Wolfgang; Schaefer, Wolfgang

229

Very Large Scale Plasma Source Ion Implantation  

NASA Astrophysics Data System (ADS)

Plasma Source Ion Implantation (PSII) is a technology in the process of being commercialized for the surface enhancement of industrial components.( Plasma-Based Processing of Materials for Motor Vehicle Components and Manufacturing Applications, National Institute of Standards and Technology, Advanced Technology Program, Focused Program 95-02) The process is based on the utilization of plasma sheath characteristics to accelerate and implant ions (in pulses ranging from ~ 1 ?sec to a few 10s of ?sec) into target surfaces which can be complex, composed of multiple individual components, and potentially have very large surface areas. The implanted ions (typically nitrogen, carbon, oxygen, or other species readily produced from gaseous precursors) modify the target surface characteristics to depths of ~ 1000 Åthrough the formation of hard nitrides, carbides, etc. which can have significantly better wear and corrosion properties than the base target material. PSII is capable of achieving surface property enhancements which are comparable to those obtained through more conventional beam line implantation, but with significant improvements in process time and cost for large, complex targets.(C.P. Munson, et al., Surface and Coatings Technology 84 (1996) 528-536.) Plasma, plasma sheath, and secondary electron interactions become critically important for applications involving implantation into three dimensional target assemblies composed of large numbers of individual components. In these cases, interaction of the plasma sheaths from different portions of the target assembly and interaction of the energetic secondary electrons with the plasma and background neutral gas can dramatically alter the ambient plasma conditions. The highly energetic (>= 20 keV) secondary electrons can approach densities which are 10% of the background plasma (ne ~ 1-5 × 10^8/cm^3, Te ~ 2-5 eV), leading to highly non-Maxwellian velocity distributions and accompanying plasma instabilities. Langmuir probe measurements from within such an assembly are being compared to particle-in-cell simulations of the plasma behavior during the implantation process. Results of the experimental measurements and comparison to the numerical simulations will be presented.

Munson, Carter P.

1997-11-01

230

An ECT/ERT dual-modality sensor for oil-water two-phase flow measurement  

SciTech Connect

This paper presents a new sensor for ECT/ERT dual-modality system which can simultaneously obtain the permittivity and conductivity of the materials in the pipeline. Quasi-static electromagnetic fields are produced by the inner electrodes array sensor of electrical capacitance tomography (ECT) system. The results of simulation show that the data of permittivity and conductivity can be simultaneously obtained from the same measurement electrode and the fusion of two kinds of data may improve the quality of the reconstructed images. For uniform oil-water mixtures, the performance of designed dual-modality sensor for measuring the various oil fractions has been tested on representative data and the results of experiments show that the designed sensor broadens the measurement range compared to single modality.

Wang, Pitao [School of Electronic Engineering and Automation, Tianjin University, 300072 and School of Electronic Engineering, University of Jinan (China); Wang, Huaxiang; Sun, Benyuan; Cui, Ziqiang [School of Electronic Engineering and Automation, Tianjin University, 300072 (China); Huang, Wenrui [HuaDian Heavy Industries Co. Ltd, Beijing, 100077 (China)

2014-04-11

231

2008 Ect Benchmark Results: Modeling with Civa of 3d Flaws Responses in Planar and Cylindrical Work Pieces  

NASA Astrophysics Data System (ADS)

The configurations proposed in the 2008 ECT modeling benchmark session are addressed in this paper using the eddy current modeling tool embedded into CIVA, which is a multi-technique simulation platform dedicated to NDT and developed at the French Atomic Energy Commission (CEA). The theoretical approach used in CIVA for ECT modeling is based on Volume integral Method (VIM) coupled with the Method of Moments (MoM) and thus leads to fast and accurate calculations in the case of canonical geometries. Symmetries of the configurations considered in this benchmark are moreover exploited by using the Dodd and Deed formalism for the field computations. After a presentation of the semi-analytical model, results obtained in all benchmark cases are discussed and compared with experimental data.

Reboud, C.; Pichenot, G.; Prémel, D.; Raillon, R.

2009-03-01

232

An ECT/ERT dual-modality sensor for oil-water two-phase flow measurement  

NASA Astrophysics Data System (ADS)

This paper presents a new sensor for ECT/ERT dual-modality system which can simultaneously obtain the permittivity and conductivity of the materials in the pipeline. Quasi-static electromagnetic fields are produced by the inner electrodes array sensor of electrical capacitance tomography (ECT) system. The results of simulation show that the data of permittivity and conductivity can be simultaneously obtained from the same measurement electrode and the fusion of two kinds of data may improve the quality of the reconstructed images. For uniform oil-water mixtures, the performance of designed dual-modality sensor for measuring the various oil fractions has been tested on representative data and the results of experiments show that the designed sensor broadens the measurement range compared to single modality.

Wang, Pitao; Wang, Huaxiang; Sun, Benyuan; Cui, Ziqiang; Huang, Wenrui

2014-04-01

233

Implantation-plasma nitriding  

NASA Astrophysics Data System (ADS)

Martensite steel 0.5Cr12Ni2MoMgMn and titanium alloy TiMo1Zr4.5Sn3 were nitrided by high intensity nitrogen plasma bombardment (current densities were 3·1016 cm-2s-1 and 1.2·1017cm-2s-1 for martensite steel and titanium alloy correspondingly). Preliminary 30-keV N+2 ion implantation and subsequent plasma treatment essentially increases N penetration depth two orders of magnitude and surface hardness by a factor ˜3. Approximately the same effect was received also at low energy (300eV) and high intensity Ar+ ion prebombardment and subsequent nitrogen plasma treatment. Near the surface a X-ray amorphous layer is created as a result of implantation-plasma treatment. High dose implanted atoms penetration is explained by their repulsive interaction and diffusion along dislocations.

Guseva, M. I.; Gordeeva, G. V.; Martynenko, Yu. V.; Atamanov, M. V.; Neumoin, V. E.; Smyslov, A. M.

234

Ion implantation in silicate glasses  

SciTech Connect

This review examines the effects of ion implantation on the physical properties of silicate glasses, the compositional modifications that can be brought about, and the use of metal implants to form colloidal nanosize particles for increasing the nonlinear refractive index.

Arnold, G.W.

1993-12-01

235

Acute and residual e V ects of vibratory stimulation on explosive strength in elite and amateur athletes  

Microsoft Academic Search

- 2 transmitted through the two-arm s handle to the arm muscles. The m echanical power of each repetition was m easured by thePower Teach' instrument. The m axim al and mean power values for each set were autom atically recorded and shown on the screen. The acute e V ect was evaluated as the diV erence between the mean

V. B. ISSURIN

236

Partial Type and E ect Inference for Rcc/Java is NP-Complete Williams College Technical Note 04-01  

E-print Network

Partial Type and E#11;ect Inference for Rcc/Java is NP-Complete Williams College Technical Note 04 of California at Santa Cruz Williams College Santa Cruz, CA 95064 Williamstown, MA 01267 February 25, 2004 1

Freund, Stephen N.

237

Journal of Magnetism and Magnetic Materials 198}199 (1999) 55}57 E!ect of deposition parameters on the CPP-GMR of  

E-print Network

-magnetoresistance; Heusler alloys Energy band calculations [1] indicate that the fer- romagnetic Heusler alloy (HA) Ni-metallic (100% spin polarized) ferromagnetic alloy NiMnSb. The observed e!ect of 5}10% is much smaller than

Reilly, Anne

238

Printing of Titanium implant prototype  

Microsoft Academic Search

Dental implant plays an important role as a conduit of force and stress to flow from the tooth to the related bone. In the load sharing between an implant and its related bone, the amount of stress carried by each of them directly related to their stiffness or modulus. Hence, it is a crucial issue for the implant to have

Florencia Edith Wiria; John Yong Ming Shyan; Poon Nian Lim; Francis Goh Chung Wen; Jin Fei Yeo; Tong Cao

2010-01-01

239

Prosthetic Failure in Implant Dentistry.  

PubMed

Although osseointegrated dental implants have become a predictable and effective modality for the treatment of single or multiple missing teeth, their use is associated with clinical complications. Such complications can be biologic, technical, mechanical, or esthetic and may compromise implant outcomes to various degrees. This article presents prosthetic complications accompanied with implant-supported single and partial fixed dental prostheses. PMID:25434566

Sadid-Zadeh, Ramtin; Kutkut, Ahmad; Kim, Hyeongil

2015-01-01

240

Investigation of droplet distribution in electrohydrodynamic atomization (EHDA) using an ac-based electrical capacitance tomography (ECT) system with an internal-external electrode sensor  

NASA Astrophysics Data System (ADS)

Electrohydrodynamic atomization (EHDA) has recently been applied to the fabrication of polymeric micro- or nano-particles or fibres for drug encapsulation. For in situ monitoring of pharmaceutical particle fabrication in an EHDA encapsulation chamber, electrical capacitance tomography (ECT) has been used as a non-invasive measurement technique. The key achievements made during this study include the successful monitoring of very dilute droplet and particle trajectories in different regions of the EHDA encapsulation chamber. The results of both a charge/discharge ECT system and an ac-based ECT system are compared. A new type of ECT sensor with internal and external electrodes is used to improve the sensitivity of ECT measurement for detection of the objects in the central area of the EHDA encapsulation chamber. The water-air and dicholoromethane (DCM)-air systems in the dripping and spray modes have been investigated to determine the feasibility of imaging water and DCM droplets of low concentration in the encapsulation chamber using ECT.

Rezvanpour, Alireza; Wang, Chi-Hwa; Liang, Yung C.; Yang, Wuqiang

2012-01-01

241

Application of confocal laser microscopy for monitoring mesh implants in herniology  

SciTech Connect

The state of the surface of mesh implants and their encapsulation region in herniology is investigated by laser confocal microscopy. A correlation between the probability of developing relapses and the size and density of implant microdefects is experimentally shown. The applicability limits of differential reverse scattering for monitoring the post-operation state of implant and adjacent tissues are established based on model numerical experiments. (optical technologies in biophysics and medicine)

Zakharov, V P; Belokonev, V I; Bratchenko, I A; Timchenko, P E; Vavilov, A V; Volova, L T

2011-04-30

242

Modeling of nanocluster formation by ion beam implantation  

SciTech Connect

A theoretical model was developed to investigate the mechanism of the formation of nanoclusters via ion beam implantation. The evolution of nanoclusters, including the nucleation and growth process known as Ostwald ripening, was rebuilt using numerical simulations. The effects of implantation parameters such as the ion energy, ion fluence, and temperature on the morphology of implanted microstructures were also studied through integration with the Monte Carlo Transport of Ions in Matter code calculation for the distribution profiles of implanted ions. With an appropriate ion fluence, a labyrinth-like nanostructure with broad size distributions of nanoclusters formed along the ion implantation range. In a latter stage, a buried layer of implanted impurity developed. With decreasing ion energy, the model predicted the formation of precipitates on the surface. These simulation results were fully consistent with many experimental observations. With increased temperature, the characteristic length and size of nanostructures would increase due to the high mobility. This theoretical model provides an efficient numerical approach for fully understanding the mechanism of the formation of nanoclusters, allowing for the design of ion beam experiments to form specific nanostructures through ion-implantation technology.

Li, Kun-Dar [Department of Materials Science, National University of Tainan, Tainan, Taiwan 700 (China)

2011-08-15

243

The Development of the Nucleus® Freedom™ Cochlear Implant System  

PubMed Central

Cochlear Limited (Cochlear™) released the fourth-generation cochlear implant system, Nucleus® Freedom™, in 2005. Freedom is based on 25 years of experience in cochlear implant research and development and incorporates advances in medicine, implantable materials, electronic technology, and sound coding. This article presents the development of Cochlear's implant systems, with an overview of the first 3 generations, and details of the Freedom system: the CI24RE receiver-stimulator, the Contour Advance™ electrode, the modular Freedom processor, the available speech coding strategies, the input processing options of SmartSound™ to improve the signal before coding as electrical signals, and the programming software. Preliminary results from multicenter studies with the Freedom system are reported, demonstrating better levels of performance compared with the previous systems. The final section presents the most recent implant reliability data, with the early findings at 18 months showing improved reliability of the Freedom implant compared with the earlier Nucleus 3 System. Also reported are some of the findings of Cochlear's collaborative research programs to improve recipient outcomes. Included are studies showing the benefits from bilateral implants, electroacoustic stimulation using an ipsilateral and/or contralateral hearing aid, advanced speech coding, and streamlined speech processor programming. PMID:17172547

Patrick, James F.; Busby, Peter A.; Gibson, Peter J.

2006-01-01

244

Multichannel implantable telemetry system  

NASA Technical Reports Server (NTRS)

Multichannel telemetry system is used for chronic implantation in animals to monitor a variety of physiological parameters. A hermetically sealed unit, the system uses a time-sharing multiplex scheme to commutate between various sensor inputs and enables the number of channels to be increased or decreased.

Fryer, T. B.

1968-01-01

245

Implantable medical sensor system  

Microsoft Academic Search

An implantable chemical sensor system for medical applications is described which permits selective recognition of an analyte using an expandable biocompatible sensor, such as a polymer, that undergoes a dimensional change in the presence of the analyte. The expandable polymer is incorporated into an electronic circuit component that changes its properties (e.g., frequency) when the polymer changes dimension. As the

Christopher B. Darrow; Satcher Jr. Joe H; Abraham P. Lee; Amy W. Wang

2001-01-01

246

Remote actuated valve implant  

DOEpatents

Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

McKnight, Timothy E; Johnson, Anthony; Moise, Jr., Kenneth J; Ericson, Milton Nance; Baba, Justin S; Wilgen, John B; Evans, III, Boyd McCutchen

2014-02-25

247

Implantable Impedance Plethysmography  

PubMed Central

We demonstrate by theory, as well as by ex vivo and in vivo measurements that impedance plethysmography, applied extravascularly directly on large arteries, is a viable method for monitoring various cardiovascular parameters, such as blood pressure, with high accuracy. The sensor is designed as an implant to monitor cardiac events and arteriosclerotic progression over the long term. PMID:25123467

Theodor, Michael; Ruh, Dominic; Ocker, Martin; Spether, Dominik; Förster, Katharina; Heilmann, Claudia; Beyersdorf, Friedhelm; Manoli, Yiannos; Zappe, Hans; Seifert, Andreas

2014-01-01

248

Implantable Drug Dispenser  

NASA Technical Reports Server (NTRS)

Drugs such as insulin are injected as needed directly into bloodstream by compact implantable dispensing unit. Two vapor cavities produce opposing forces on drug-chamber diaphragm. Heaters in cavities allow control of direction and rate of motion of bellows. Dispensing capsule fitted with coil so batteries can be recharged by induction.

Collins, E. R. J.

1983-01-01

249

Implantable electrical device  

NASA Technical Reports Server (NTRS)

A fully implantable and self contained device is disclosed composed of a flexible electrode array for surrounding damaged nerves and a signal generator for driving the electrode array with periodic electrical impulses of nanoampere magnitude to induce regeneration of the damaged nerves.

Jhabvala, M. D. (inventor)

1982-01-01

250

Basic design and construction of the Vienna FES implants: existing solutions and prospects for new generations of implants.  

PubMed

We can distinguish 3 generations of FES implants for activation of neural structures: 1. RF-powered implants with antenna displacement dependent stimulation amplitude; 2. RF-powered implants with stabilised stimulation amplitude; and 3. battery powered implants. In Vienna an 8-channel version of the second generation type has been applied clinically to mobilisation of paraplegics and phrenic pacing. A 20-channel implant of the second generation type for mobilisation of paraplegics and an 8-channel implant of the third generation type for cardiac assist have been tested in animal studies. A device of completely new design for direct stimulation of denervated muscles is being tested in animal studies. There is a limited choice of technologically suitable biocompatible and bioresistant materials for implants. The physical design has to be anatomically shaped without corners or edges. Electrical conductors carrying direct current (D.C.) have to be placed inside a hermetic metal case. The established sealing materials, silicone rubber and epoxy resin, do not provide hermeticity and should only embed DC-free components. For electrical connections outside the hermetic metal case welding is preferable to soldering; conductive adhesives should be avoided. It is advisable to use a hydrophobic oxide ceramic core for telemetry antenna coils embedded in sealing polymer. Cleaning of all components before sealing in resin is of the utmost importance as well as avoidance of rapid temperature changes during the curing process. PMID:11344008

Mayr, W; Bijak, M; Rafolt, D; Sauermann, S; Unger, E; Lanmüller, H

2001-01-01

251

Industrial applications of ion implantation into metal surfaces  

SciTech Connect

The modern materials processing technique, ion implantation, has intriguing and attractive features that stimulate the imaginations of scientists and technologists. Success of the technique for introducing dopants into semiconductors has resulted in a stable and growing infrastructure of capital equipment and skills for use of the technique in the economy. Attention has turned to possible use of ion implantation for modification of nearly all surface related properties of materials - optical, chemical and corrosive, tribological, and several others. This presentation provides an introduction to fundamental aspects of equipment, technique, and materials science of ion implantation. Practical and economic factors pertaining to the technology are discussed. Applications and potential applications are surveyed. There are already available a number of ion-implanted products, including ball-and-roller bearings and races, punches-and-dies, injection screws for plastics molding, etc., of potential interest to the machine tool industry.

Williams, J.M.

1987-07-01

252

SEM analysis of ion implanted SiC  

NASA Astrophysics Data System (ADS)

SiC is a material used in two future energy production technologies, firstly as a photovoltaic layer to harness the UV spectrum in high efficient power solar cells, and secondly as a diffusion barrier material for radioactive fission products in the fuel elements of the next generation of nuclear power plants. For both applications, there is an interest in the implantation of reactive and non-reactive ions into SiC and their effects on the properties of the SiC. In this study 360 keV Ag+, I+ and Xe+ ions were separately implanted into 6H-SiC and in polycrystalline SiC at various substrate temperatures. The implanted samples were also annealed in vacuum at temperatures ranging from 900 °C to 1600 °C for various times. In recent years, there had been significant advances in scanning electron microscopy (SEM) with the introduction of an in-lens detector combined with field emission electron guns. This allows defects in solids, such as radiation damage created by the implanted ions, to be detected with SEM. Cross-sectional SEM images of 6H-SiC wafers implanted with 360 keV Ag+ ions at room temperature and at 600 °C and then vacuum annealed at different temperatures revealed the implanted layers and their thicknesses. A similar result is shown of 360 keV I+ ions implanted at 600 °C into 6H-SiC and annealed at 1600 °C. The 6H-SiC is not amorphized but remained crystalline when implanting at 600 °C. There are differences in the microstructure of 6H-SiC implanted with silver at the two temperatures as well as with reactive iodine ions. Voids (bubbles) are created in the implanted layers into which the precipitation of silver and iodine can occur after annealing of the samples. The crystallinity of the substrate via implantation temperature caused differences in the distribution and size of the voids. Implantation of xenon ions in polycrystalline SiC at 350 °C does not amorphize the substrate as is the case with room temperature heavy ion bombardment. Subsequent annealing of the implanted polycrystalline samples leads to increased thermal etching effects such as grain boundary grooving. Damage due to channelling (or non-channelling) in the different crystallites resulted also in differences in thermal etching in the crystallites.

Malherbe, Johan B.; van der Berg, N. G.; Botha, A. J.; Friedland, E.; Hlatshwayo, T. T.; Kuhudzai, R. J.; Wendler, E.; Wesch, W.; Chakraborty, P.; da Silveira, E. F.

2013-11-01

253

Revision and salvage patellar arthroplasty using a porous tantalum implant 1 1 No benefits or funds were received in support of this study. Dr. Poggie is an employee of Zimmer Trabecular Metal Technology, Inc., Allendale, NJ  

Microsoft Academic Search

The purpose of this study was to assess the clinical results of a new surgical technique and novel porous tantalum implant for augmentation or arthroplasty of the patella for 11 patients who underwent revision total knee arthroplasty. Preoperative average knee function and pain scores were 24 and 20, respectively, and average range of motion (ROM) was 62°. The low knee

Sam Nasser; Robert A Poggie

2004-01-01

254

Ablation plasma ion implantation  

NASA Astrophysics Data System (ADS)

The novel hybrid technique, Ablation Plasma Ion Implantation (APII), has been characterized and optimized for ion implantation and/or thin film deposition. In APII, a solid target is ablated by a laser; the resulting plasma plume is the source of ions, which are accelerated to high energy by a negative bias voltage imposed on the substrate. The ions are implanted into the substrate, and the neutral atoms in the ablation plume deposit on the substrate in the form of a thin film. Two configurations of APII are characterized and compared. The parallel target-substrate configuration yields ion-beam-assisted deposition and/or ion implantation, and the perpendicular target-substrate configuration yields pure ion implantation mode. A novel theory of the ion matrix sheath has been developed for APII. The ion current predicted by the Child-Langmuir sheath theory matches well with the experimental ion current. Two different target-substrate orientations have been compared for APII. Parallel target-substrate orientation yields ion-beam-assisted-deposition and ion implantation; to prevent arcing, a laser-voltage delay of several microseconds is required for this mode. For the optimized perpendicular target-substrate orientation, the laser can be fired during the voltage pulse, thereby accelerating ions to full energy. Furthermore, the ion dose is higher than that of the parallel target-substrate orientation by a factor of two. The parameters of plasma plumes have been thoroughly characterized by numerous diagnostics, which include electrical characteristics, optical emission spectroscopy, dye laser resonance absorption photography, resonant/non-resonant interferometry, and Langmuir probe. The total number of ions measured by Langmuir probe, and resonant interferometry, is in the range of 1014 ions per laser pulse. Ion dose measured by plasma diagnostics, has been correlated to the ion dose obtained from material analysis, including sputtering yield calculation, X-ray Energy Dispersive Spectroscopy and X-ray Photoelectron Spectroscopy. The retained and delivered ion doses are in the range of 10 12/cm2 per pulse, which is favorable compared to the ion dose obtained from conventional Plasma Immersion Ion Implantation (PHI). The APII ion implantation efficiency is estimated to be about 2%. Ion acceleration and implantation was demonstrated for both of the APB configurations. The feasibility of APII was verified by Cross-Sectional Transmission Electron Microscopy and X-ray Photoelectron Spectroscopy. For parallel target-substrate configuration, the average deposition rate is 0.0075 nm/shot for the Ti -10 kV APII film. Atomic Force Microscopy implemented at Timken Research Lab indicates that the -4 kV APII film has the smoothest surface. Scratch tests performed at Timken Research lab also prove that APR produces excellent film adhesion.

Qi, Bo

255

Models and Signal Processing for an Implanted Ethanol BioSensor  

Microsoft Academic Search

The understanding of drinking patterns leading to alcoholism has been hindered by an inability to unobtrusively measure ethanol consumption over periods of weeks to months in the community environment. An implantable ethanol sensor is under development using microelectromechanical systems technology. For safety and user acceptability issues, the sensor will be implanted subcutaneously and, therefore, measure peripheral-tissue ethanol concentration. Determining ethanol

Han Jae-Joon; Peter C. Doerschuk; Saul B. Gelfand; Sean J. O'Connor

2008-01-01

256

Left ventricular assist device implantation: short and long-term surgical complications  

Microsoft Academic Search

Long-term implanted left ventricular assist devices (LVADs) have significantly improved the care of patients awaiting heart transplantation and will provide an alternative therapy to select patients with heart failure. However, although the technology and clinical results continue to improve, LVAD implantation is still associated with a significant level of complications. Left ventricular assist device–associated complications can be broadly divided by

William Piccione

2000-01-01

257

A Wireless Power Interface for Rechargeable Battery Operated Neural Recording Implants  

E-print Network

A Wireless Power Interface for Rechargeable Battery Operated Neural Recording Implants Pengfei Li a biocompatible rechargeable battery. As battery technology continues to advance toward higher volumetric for a low power elec- tronic interface capable of supporting a rechargeable battery implant framework

Slatton, Clint

258

Bored By Non-Glowing Skin? Ultra-Flexible, Waterproof LED Implants Are What You Seek  

E-print Network

Bored By Non-Glowing Skin? Ultra-Flexible, Waterproof LED Implants Are What You Seek By Alasdair Wilkins/io9 Posted 10.19.2010 at 12:15 pm LED Lights Could Be Implanted Under Skin Photo courtesy of iO9 LEDs are, on small scales, the cheapest, most reliable, and most technologically powerful light sources

Rogers, John A.

259

CAD/CAM implant abutments using coded healing abutments: a detailed description of the restorative process.  

PubMed

Computer-aided design/computer-aided manufacturing (CAD/CAM) represents a leap forward in the fabrication of implant restorations. Coded healing abutments can be digitally read, and they eliminate the steps needed to make implant impressions using traditional impression copings. This article provides a detailed description of the restorative process using CAD/CAM technology and coded healing abutments. PMID:24564614

Mahn, Douglas H; Prestipino, Tony

2013-09-01

260

Transapical endovascular implantation of neochordae using a suction and suture device  

Microsoft Academic Search

Objective: Neochordae implantation is a standard method for treatment of mitral valve prolapse. We describe a transcatheter technology enabling transapical endovascular chordal implantation. Methods: Six adult pigs were anesthetized. Two 10F sheaths were introduced in the femoral vessels for monitoring and intracardiac echo. After midline sternotomy, the pericardium was opened, the apex was punctured inside two 2–0 polypropylene purse strings.

Francesco Maisano; Iassen Michev; Stanton Rowe; Alessandro Addis; Marino Campagnol; Andrea Guidotti; Antonio Colombo; Ottavio Alfieri

2009-01-01

261

Time encoding and reconstruction of multichannel data by brain implants using asynchronous sigma delta modulators  

Microsoft Academic Search

Recently, information technology and microelectronics have enabled implanting miniature and highly intelligent devices within the brain for in-vitro diagnostic and therapeutic functions. Power and physical size constraints of these devices necessitate novel signal processing methods. In this paper we investigate an effective data acquisition and reconstruction method for brain implants based on asynchronous sigma delta modulators (ASDMs). The ASDMs are

Seda Senay; Luis F. Chaparro; Robert J. Sclabassi; Mingui Sun

2009-01-01

262

Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges  

PubMed Central

With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of implanted device research in the future. This review will hopefully lead to increasing efforts towards the development of low powered, highly efficient, high data rate and reliable automatic frequency controllers for implanted devices. PMID:25615728

Hannan, Mahammad A.; Hussein, Hussein A.; Mutashar, Saad; Samad, Salina A.; Hussain, Aini

2014-01-01

263

BF{sub 3} PIII modeling: Implantation, amorphisation and diffusion  

SciTech Connect

In the race for highly doped ultra-shallow junctions (USJs) in complementary metal oxide semi-conductor (CMOS) technologies, plasma immersion ion implantation (PIII) is a promising alternative to traditional beamline implantation. Currently, no commercial technology computer aided design (TCAD) process simulator allows modeling the complete USJ fabrication process by PIII, including as-implanted dopant profiles, damage formation, dopant diffusion and activation. In this work, a full simulation of a p-type BF{sub 3} PIII USJ has been carried out. In order to investigate the various physical phenomena mentioned above, process conditions included a high energy/high dose case (10 kV, 5 Multiplication-Sign 10{sup 15} cm{sup -2}), specifically designed to increase damage formation, as well as more technology relevant implant conditions (0.5 kV) for comparison. All implanted samples were annealed at different temperatures and times. As implanted profiles for both boron and fluorine in BF{sub 3} implants were modeled and compared to Secondary Ion Mass Spectrometry (SIMS) measurements. Amorphous/crystalline (a/c) interface depths were measured by transmission electron microscopy (TEM) and successfully simulated. Diffused profiles simulations agreed with SIMS data at low thermal budgets. A boron peak behind the a/c interface was observed in all annealed SIMS profiles for the 10 kV case, indicating boron trapping from EOR defects in this region even after high thermal budgets. TEM measurements on the annealed samples showed an end of range (EOR) defects survival behind the a/c interface, including large dislocation loops (DLs) lying on (001) plane parallel to the surface. In the last part of this work, activation simulations were compared to Hall measurements and confirmed the need to develop a (001) large BICs model.

Essa, Z.; Cristiano, F.; Spiegel, Y.; Boulenc, P.; Qiu, Y.; Quillec, M.; Taleb, N.; Burenkov, A.; Hackenberg, M.; Bedel-Pereira, E.; Mortet, V.; Torregrosa, Frank; Tavernier, C. [STMicroelectronics 850 rue Jean Monnet F-38926 Crolles France and LAAS-CNRS 7 av. du Col. Roche 31077 Toulouse (France); LAAS-CNRS 7 av. du Col. Roche 31077 Toulouse (France); IBS av. Gaston Imbert prolongee 13790 Peynier Rousset (France); STMicroelectronics 850 rue Jean Monnet F-38926 Crolles (France); LAAS-CNRS 7 av. du Col. Roche 31077 Toulouse (France); Probion Analysis 37 rue de Fontenay 92220 Bagneux (France); Fraunhofer IISB Schottkystrasse 10, 91058 Erlangen (Germany); LAAS-CNRS 7 av. du Col. Roche 31077 Toulouse (France); IBS av. Gaston Imbert prolongee 13790 Peynier Rousset (France); STMicroelectronics 850 rue Jean Monnet F-38926 Crolles (France)

2012-11-06

264

Tissue response to the components of a hydroxyapatite-coated composite femoral implant.  

PubMed

Bone loss around femoral implants used for THA is a persistent clinical concern. It may be caused by stress shielding, generally attributed to a mismatch in stiffness between the implants and host bone. In this regard, a fatigue resistant, carbon fiber (CF) composite femoral implant with bone-matching stiffness has been developed. This study evaluated the tissue response to the three material components of this implant in normal and textured (blasted with 24 grit alumina) surfaces: the hydroxyapatite (HA) coating, the CF composite and the intermediate crystalline HA particulate composite layer to bond to the HA coating (blended). Sprague-Dawley rats underwent bilateral femoral implantation each receiving two rod-like implants. Bone apposition to the HA (37%) and textured Ti (41%) implants was not significantly different. Bone apposition to the untextured CF (14%) and blended (19%) implants and polished Ti (8%) implants was significantly lower. Bone apposition to the textured CF (9%) and blended (11%) implants was lower (but not statistically from the as received or untextured counterparts). Nearly all sections from femurs containing CF implants presented CF debris. There was no evidence of localized bone loss or any strong immune response associated with any of the implant materials. All materials were well tolerated with minimal inflammation despite the presence of particulate debris. The high degree of bone apposition to the HA-coated composite implants and the lack of short-term inflammation and adverse tissue response to the three material implant component support continued evaluation of this composite technology for use in THA. PMID:20730932

Hacking, S A; Pauyo, T; Lim, L; Legoux, J G; Bureau, M N

2010-09-01

265

The socially constructed breast: breast implants and the medical construction of need.  

PubMed Central

When silicone gel breast implants became the subject of a public health controversy in the early 1990s, the most pressing concern was safety. This paper looks at another, less publicized issue: the need for implants. Using a symbolic interactionist approach, the author explores the social construction of the need for implants by tracing the history of the 3 surgical procedures for which implants were used. Stakeholders in this history constructed need as legitimized individual desire, the form of which shifted with changes in the technological and social context. PMID:9702166

Jacobson, N

1998-01-01

266

Miniature implantable ultrasonic echosonometer  

NASA Technical Reports Server (NTRS)

A miniature echosonometer adapted for implantation in the interior of an animal for imaging the internal structure of a organ, tissue or vessel is presented. The echosonometer includes a receiver/transmitter circuit which is coupled to an ultrasonic transducer. Power is coupled to the echosonometer by electromagnetic induction through the animal's skin. Imaging signals from the echosonometer are electromagnetically transmitted through the animal's skin to an external readout apparatus.

Kojima, G. K. (inventor)

1978-01-01

267

Autologous Chondrocyte Implantation  

Microsoft Academic Search

Currently, autologous chondrocyte implantation (ACI) is ideally indicated for symptomatic ICRS grade III-IV lesions greater\\u000a than 2 cm2 along the femoral condyle or trochlear regions. High-demand patients between the ages of 15 to 55 years of age with excellent\\u000a motivation and compliance potential should be chosen. Lars Peterson assessed his first 101 patients at intermediate to long-term\\u000a follow-up. Good to

Deryk G. Jones; Lars Peterson

268

Biocompatibility and biofunctionality of implanted materials.  

PubMed

The mechanical and chemical properties of metals, such as titanium, titanium-based alloys and cobalt-based alloys, and ceramics, such as Bioglass and calcium phosphate, make them suitable for implant applications. However, several factors affect the biologic response to these implanted materials. The predominant tissue found at the implant interface is affected by implant stability, material biocompatibility, and implant design and implant placement into the surgical site. Improvements in implant design and surface preparation may improve implant longevity and fixation for all implants materials. PMID:1308341

Cook, S D; Dalton, J E

1992-01-01

269

Sub-meninges implantation reduces immune response to neural implants.  

PubMed

Glial scar formation around neural interfaces inhibits their ability to acquire usable signals from the surrounding neurons. To improve neural recording performance, the inflammatory response and glial scarring must be minimized. Previous work has indicated that meningeally derived cells participate in the immune response, and it is possible that the meninges may grow down around the shank of a neural implant, contributing to the formation of the glial scar. This study examines whether the glial scar can be reduced by placing a neural probe completely below the meninges. Rats were implanted with sets of loose microwire implants placed either completely below the meninges or implanted conventionally with the upper end penetrating the meninges, but not attached to the skull. Histological analysis was performed 4 weeks following surgical implantation to evaluate the glial scar. Our results found that sub-meninges implants showed an average reduction in reactive astrocyte activity of 63% compared to trans-meninges implants. Microglial activity was also reduced for sub-meninges implants. These results suggest that techniques that isolate implants from the meninges offer the potential to reduce the encapsulation response which should improve chronic recording quality and stability. PMID:23370311

Markwardt, Neil T; Stokol, Jodi; Rennaker, Robert L

2013-04-15

270

Evaluation of the Edge Crack Torsion (ECT) Test for Mode 3 Interlaminar Fracture Toughness of Laminated Composites  

NASA Technical Reports Server (NTRS)

An analytical and experimental investigation was carried out on G40-800/R6376 graphite epoxy laminates to evaluate the Edge Crack Torsion (ECT) test as a candidate for a standard Mode 3 interlaminar fracture toughness test for laminated composites. The ECT test consists of a (90/(+/- 45)(sub 3)/(+/- 45)(sub 3)/90))(sub s) laminate with a delamination introduced by a non-adhesive film at the mid-plane along one edge and loaded in a special fixture to create torsion along the length of the laminate. Dye penetrate enhanced X-radiograph of failed specimens revealed that the delamination initiated at the middle of the specimen length and propagated in a self similar manner along the laminate mid-plane. A three-dimensional finite element analysis was performed that indicated that a pure Mode 3 delamination exists at the middle of specimen length away from both ends. At the ends near the loading point a small Mode 2 component exists. However, the magnitude of this Mode 2 strain energy release rate at the loading point is small compared to the magnitude of Mode 3 component in the mid-section of the specimen. Hence, the ECT test yielded the desired Mode 3 delamination. The Mode 3 fracture toughness was obtained from a compliance calibration method and was in good agreement with the finite element results. Mode 2 End-Notched Flexure (ENF) tests and Mode 1 Double Cantilever Beam (DCB) tests were also performed for the same composite material. The Mode 1 fracture toughness was much smaller than both the Mode 2 and Mode 3 fracture toughness. The Mode 2 fracture toughness was found to be 75% of the Mode 3 fracture toughness.

Li, Jian; Lee, Edward W.; OBrien, T. Kevin; Lee, Shaw Ming

1996-01-01

271

Implanted renal replacement for end-stage renal disease.  

PubMed

The nearly 400000 American patients on dialysis suffer high cardiovascular and infectious mortality, but there is now evidence that this morbid phenotype can be rescued by intensive dialytic therapy. Self-care dialysis at home is limited by patient fears about skill and safety. An implanted artificial kidney would provide the benefits of intensive therapy while avoiding the focal points of patient concern. Hollow fiber polymer membranes and dialytic waste removal are lifesaving innovations but are difficult to adapt to implantable therapies. Biomimetic membranes and living cells can replicate the native kidney's strategy for waste removal. Three key technology developments are necessary for implementation of an implantable artificial kidney: high efficiency ultrafiltration membranes, control of blood-materials interactions such as thrombosis and fouling, and stable differentiated function of renal proximal tubule cells in an engineered construct. There has been significant progress in demonstrating proof-of-concept experiments in each key technology area. PMID:21775942

Roy, S; Goldman, K; Marchant, R; Zydney, A; Brown, D; Fleischman, A; Conlisk, A; Desai, T; Duffy, S; Humes, H; Fissell, W

2011-09-01

272

Electrical capacitance tomography (ECT) and gamma radiation meter for comparison with and validation and tuning of computational fluid dynamics (CFD) modeling of multiphase flow  

NASA Astrophysics Data System (ADS)

The electrical capacitance tomographic (ECT) approach is increasingly seen as attractive for measurement and control applications in the process industries. Recently, there is increased interest in using the tomographic details from ECT for comparing with and validating and tuning CFD models of multiphase flow. Collaboration with researchers working in the field of computational fluid dynamics (CFD) modeling of multiphase flows gives valuable information for both groups of researchers in the field of ECT and CFD. By studying the ECT tomograms of multiphase flows under carefully monitored inflow conditions of the different media and by obtaining the capacitance values, C(i, j, t) with i = 1…N, j = 1,?2,…N and i ? j obtained from ECT modules with N electrodes, it is shown how the interface heights in a pipe with stratified flow of oil and air can be fruitfully compared to the values of those obtained from ECT and gamma radiation meter (GRM) for improving CFD modeling. Monitored inflow conditions in this study are flow rates of air, water and oil into a pipe which can be positioned at varying inclinations to the horizontal, thus emulating the pipelines laid in subsea installations. It is found that ECT-based tomograms show most of the features seen in the GRM-based visualizations with nearly one-to-one correspondence to interface heights obtained from these two methods, albeit some anomalies at the pipe wall. However, there are some interesting features the ECT manages to capture: features which the GRM or the CFD modeling apparently do not show, possibly due to parameters not defined in the inputs to the CFD model or much slower response of the GRM. Results presented in this paper indicate that a combination of ECT and GRM and preferably with other modalities with enhanced data fusion and analysis combined with CFD modeling can help to improve the modeling, measurement and control of multiphase flow in the oil and gas industries and in the process industries in general. This article was invited for the special feature on Imaging Systems and Techniques 2012, published in July 2013.

Pradeep, Chaminda; Yan, Ru; Vestøl, Sondre; Melaaen, Morten C.; Mylvaganam, Saba

2014-07-01

273

Chromosomal localization of the human ECT2 proto-oncogene to 3q26.1 {yields} q26.2 by somatic cell analyses and fluorescence in situ hybridization  

SciTech Connect

The mouse ect2 oncogene was identified in a search of mitogenic signal transducers using a novel expression cloning strategy. In this system, the introduction of an appropriate expression-cDNA library prepared from the mRNA of one cell type into another can result in the morphological transformation of the recipient cells. The predicted Ect2 protein has sequence similarity within a central core of 255 amino acids to the products of the breakpoint-cluster gene, bcr, the yeast cell cycle gene, CDC24, the dbl and vav oncogenes, and the RasGrf gene. Baculovirus-expressed Ect2 protein shows specific binding to Rho and Rac proteins, indicating that Ect2 is a new member of transforming proteins that can interact with Rho-like proteins of the Ras superfamily. The ect2 foci exhibit an unusual stellate morphology and are capable of forming tumors when subcutaneously inoculated in nude mice. These results indicate that the ect2 gene acts as an oncogene. To investigate the involvement of the ect2 in human tumors, the authors isolated the human homolog, ECT2, of mouse ect2 and determined its chromosomal localization. 13 refs., 1 fig.

Takai, Setsuo; Yamada, Kiyomi [International Medical Center of Japan, Tokyo (Japan)] [International Medical Center of Japan, Tokyo (Japan); Long, J.E. [National Cancer Institute, Bethesda, MD (United States)] [and others] [National Cancer Institute, Bethesda, MD (United States); and others

1995-05-01

274

Implant stategies for Littlefield Feedyard  

E-print Network

Acknowledgements Table of Contents List of Tables List of Figures Internship Introduction Objectives Literature Review Approach Results Literature Cited Vita tv 10 29 31 List of Tables 1. Available Implants to the Feedyard Industry 2. Cost... responsible for ordering iinplants and other drugs administered at reimplantation. Literature Review Before a discussion can be undertaken on which implant program is best for a particular situation, an understanding of what function implants serve and why...

Turner, John Sutton

2012-06-07

275

Imaging breasts with silicone implants  

Microsoft Academic Search

.   Over the last two decades, the use of breast implants both for breast augmentation and for breast reconstruction following\\u000a mastectomy has increased substantially. It is estimated that around two million women have undergone breast augmentation,\\u000a while hundreds of thousands have had breast reconstruction surgery. Different types of material have been used for breast\\u000a implants, but silicone gel implants have

E. Azavedo; B. Boné

1999-01-01

276

The evolution of breast implants.  

PubMed

Breast augmentation remains one of the most common aesthetic procedures performed in the United States. Silicone implants have undergone an evolution with the availability of both fourth- and fifth-generation devices from the 3 leading manufacturers in the United States. This article explores the evolution of breast implants with special emphasis on the advancement of the silicone implants. Clinicians should strive to provide ongoing data and sound science to continue to improve clinical outcomes in the future. PMID:25057743

Maxwell, G Patrick; Gabriel, Allen

2014-07-01

277

Antibacterial coatings on titanium implants.  

PubMed

Titanium and titanium alloys are key biomedical materials because of their good biocompatibility and mechanical properties. Nevertheless, infection on and around titanium implants still remains a problem which is usually difficult to treat and may lead to eventual implant removal. As a result, preventive measures are necessary to mitigate implant-frelated infection. One important strategy is to render the implant surface antibacterial by impeding the formation of a biofilm. A number of approaches have been proposed for this purpose and they are reviewed in this article. PMID:19637369

Zhao, Lingzhou; Chu, Paul K; Zhang, Yumei; Wu, Zhifen

2009-10-01

278

Esthetic Failure in Implant Dentistry.  

PubMed

The definition of failure for dental implants has evolved from lack of osseointegration to increased concern for other aspects, such as esthetics. However, esthetic failure in implant dentistry has not been well defined. Although multiple esthetic indices have been validated for objectively evaluating clinical outcomes, including failure of an implant-supported crown, only one author has determined a failure threshold. On the basis of objective indices, esthetic failures in implant dentistry can be categorized as pink-tissue failures and white-tissue failures. This article discusses esthetic failures, the factors involved in these failures, and their prevention and treatment. PMID:25434568

Fuentealba, Rodrigo; Jofré, Jorge

2015-01-01

279

Implant biomaterials: A comprehensive review.  

PubMed

Appropriate selection of the implant biomaterial is a key factor for long term success of implants. The biologic environment does not accept completely any material so to optimize biologic performance, implants should be selected to reduce the negative biologic response while maintaining adequate function. Every clinician should always gain a thorough knowledge about the different biomaterials used for the dental implants. This article makes an effort to summarize various dental bio-materials which were used in the past and as well as the latest material used now. PMID:25610850

Saini, Monika; Singh, Yashpal; Arora, Pooja; Arora, Vipin; Jain, Krati

2015-01-16

280

Implant biomaterials: A comprehensive review  

PubMed Central

Appropriate selection of the implant biomaterial is a key factor for long term success of implants. The biologic environment does not accept completely any material so to optimize biologic performance, implants should be selected to reduce the negative biologic response while maintaining adequate function. Every clinician should always gain a thorough knowledge about the different biomaterials used for the dental implants. This article makes an effort to summarize various dental bio-materials which were used in the past and as well as the latest material used now. PMID:25610850

Saini, Monika; Singh, Yashpal; Arora, Pooja; Arora, Vipin; Jain, Krati

2015-01-01

281

Implantable medical devices MRI safe.  

PubMed

Pacemakers, ICDs, neurostimulators like deep brain stimulator electrodes, spiral cord stimulators, insulin pumps, cochlear implants, retinal implants, hearing aids, electro cardio gram (ECG) leads, or devices in interventional MRI such as vascular guide wires or catheters are affected by MRI magnetic and electromagnetic fields. Design of MRI Safe medical devices requires computer modeling, bench testing, phantom testing, and animal studies. Implanted medical devices can be MRI unsafe, MRI conditional or MRI safe (see glossary). In the following paragraphs we will investigate how to design implanted medical devices MRI safe. PMID:23739365

Dal Molin, Renzo; Hecker, Bertrand

2013-01-01

282

An Implantable MEMS Drug Delivery Device for Rapid Delivery in Ambulatory Emergency Care  

E-print Network

We introduce the first implantable drug delivery system based on MEMS (Micro-Electro-Mechanical-Systems) technology specifically designed as a platform for treatment in ambulatory emergency care. The device is named ...

Elman, Noel

283

Emergency delivery of Vasopressin from an implantable MEMS rapid drug delivery device  

E-print Network

An implantable rapid drug delivery device based on micro-electro-mechanical systems (MEMS) technology was designed, fabricated and validated for the in vivo rapid delivery of vasopressin in a rabbit model. In vitro ...

Ho Duc, Hong Linh, 1978-

2009-01-01

284

Development of Implantable Medical Devices: From an Engineering Perspective  

PubMed Central

From the first pacemaker implant in 1958, numerous engineering and medical activities for implantable medical device development have faced challenges in materials, battery power, functionality, electrical power consumption, size shrinkage, system delivery, and wireless communication. With explosive advances in scientific and engineering technology, many implantable medical devices such as the pacemaker, cochlear implant, and real-time blood pressure sensors have been developed and improved. This trend of progress in medical devices will continue because of the coming super-aged society, which will result in more consumers for the devices. The inner body is a special space filled with electrical, chemical, mechanical, and marine-salted reactions. Therefore, electrical connectivity and communication, corrosion, robustness, and hermeticity are key factors to be considered during the development stage. The main participants in the development stage are the user, the medical staff, and the engineer or technician. Thus, there are three different viewpoints in the development of implantable devices. In this review paper, considerations in the development of implantable medical devices will be presented from the viewpoint of an engineering mind. PMID:24143287

2013-01-01

285

Development of implantable medical devices: from an engineering perspective.  

PubMed

From the first pacemaker implant in 1958, numerous engineering and medical activities for implantable medical device development have faced challenges in materials, battery power, functionality, electrical power consumption, size shrinkage, system delivery, and wireless communication. With explosive advances in scientific and engineering technology, many implantable medical devices such as the pacemaker, cochlear implant, and real-time blood pressure sensors have been developed and improved. This trend of progress in medical devices will continue because of the coming super-aged society, which will result in more consumers for the devices. The inner body is a special space filled with electrical, chemical, mechanical, and marine-salted reactions. Therefore, electrical connectivity and communication, corrosion, robustness, and hermeticity are key factors to be considered during the development stage. The main participants in the development stage are the user, the medical staff, and the engineer or technician. Thus, there are three different viewpoints in the development of implantable devices. In this review paper, considerations in the development of implantable medical devices will be presented from the viewpoint of an engineering mind. PMID:24143287

Joung, Yeun-Ho

2013-09-01

286

A remotely powered implantable biomedical system with location detector.  

PubMed

An universal remote powering and communication system is presented for the implantable medical devices. The system be interfaced with different sensors or actuators. A mobile external unit controls the operation of the implantable chip and reads the sensor's data. A locator system is proposed to align the mobile unit with the implant unit for the efficient magnetic power transfer. The location of the implant is detected with 6 mm resolution from the rectified voltage level at the implanted side. The rectified voltage level is fedback to the mobile unit to adjust the magnetic field strength and maximize the efficiency of the remote powering system. The sensor's data are transmitted by using a free running oscillator modulated with on-off key scheme. To tolerate large data carrier drifts, a custom designed receiver is implemented for the mobile unit. The circuits have been fabricated in 0.18 um CMOS technology. The remote powering link is optimized to deliver power at 13.56 MHz. On chip voltage regulator creates 1.8 V from a 0.9 V reference voltage to supply the sensor/actuator blocks. The implantable chip dissipates 595 ?W and requires 1.48 V for start up. PMID:24988596

Kilinc, Enver G; Ghanad, Mehrdad A; Maloberti, Franco; Dehollain, Catherine

2015-02-01

287

Implanted p+n-Junctions in Silicon Carbide  

NASA Astrophysics Data System (ADS)

Ion implantation is considered a key technology for the realisation of silicon carbide electronic devices. Here we will give an overview of the field and present some recent results of ion implanted 4H SiC epitaxial layers. Mainly Al ions of keV energies have been used at different fluence, flux and target temperature. The samples have been investigated by secondary ion mass spectrometry (SIMS), channeling Rutherford backscattering (RBS-c) and transmission electron microscopy (TEM), both as-implanted and after annealing up to 1900 °C. Also the electrical activation of Al-implanted and annealed material has been investigated by scanning spreading resistance microscopy (SSRM). The damage accumulation, monitored by RBS-c, is linear with ion fluence but depends strongly on implantation temperature and ion flux. Annealing at temperatures above 1700 °C is needed to remove the damage and to electrically activate implanted Al ions. At these high annealing temperatures, however, dislocation loops are formed that have a negative influence on device performance.

Hallén, A.; Janson, M. S.; Osterman, J.; Zimmermann, U.; Linnarsson, M.; Kuznetsov, A.; Zhang, Y.; Persson, P. O. A.?.; Svensson, B. G.

2003-08-01

288

Implanted p+n-Junctions in Silicon Carbide  

SciTech Connect

Ion implantation is considered a key technology for the realisation of silicon carbide electronic devices. Here we will give an overview of the field and present some recent results of ion implanted 4H SiC epitaxial layers. Mainly Al ions of keV energies have been used at different fluence, flux and target temperature. The samples have been investigated by secondary ion mass spectrometry (SIMS), channeling Rutherford backscattering (RBS-c) and transmission electron microscopy (TEM), both as-implanted and after annealing up to 1900 deg. C. Also the electrical activation of Al-implanted and annealed material has been investigated by scanning spreading resistance microscopy (SSRM). The damage accumulation, monitored by RBS-c, is linear with ion fluence but depends strongly on implantation temperature and ion flux. Annealing at temperatures above 1700 deg. C is needed to remove the damage and to electrically activate implanted Al ions. At these high annealing temperatures, however, dislocation loops are formed that have a negative influence on device performance.

Hallen, A.; Janson, M.S.; Osterman, J.; Zimmermann, U.; Linnarsson, M. [Dept. of Microelectronics and Information Technology, Royal Inst. of Technology, P.O. Box Electrum 229, SE 164 40 Kista (Sweden); Kuznetsov, A.; Svensson, B.G. [Physics Dept., Physical Electronics, University of Oslo, PB 1048, Blindern, N 0316 Oslo (Norway); Zhang, Y. [Div. of Ion Physics, A ring ngstroem Laboratory, Uppsala University, P.O. Box 534, SE 751 21 Uppsala (Sweden); Persson, P.O.A. [Thin Film Physics Div., Dept. of Physics, Linkoeping University, SE 581 83 Linkoeping (Sweden)

2003-08-26

289

Pressure based mass flow control for ion implant SDS applications  

Microsoft Academic Search

Thermal mass flow control (MFC) has been used to control the flow of gas in semiconductor process systems for many years. With the introduction of SDS gas sources for ion implantation, improvements in mass flow control technology were required to maximize cylinder yield and effect a corresponding reduction in operating cost. Pressure-based MFC (PMFC) is an alternative to thermal flow

R. L. Brown; J. M. Schwartz

1999-01-01

290

Single Color Centers Implanted in Diamond Nanostructures  

E-print Network

The development of materials processing techniques for optical diamond nanostructures containing a single color center is an important problem in quantum science and technology. In this work, we present the combination of ion implantation and top-down diamond nanofabrication in two scenarios: diamond nanopillars and diamond nanowires. The first device consists of a 'shallow' implant (~20nm) to generate Nitrogen-vacancy (NV) color centers near the top surface of the diamond crystal. Individual NV centers are then isolated mechanically by dry etching a regular array of nanopillars in the diamond surface. Photon anti-bunching measurements indicate that a high yield (>10%) of the devices contain a single NV center. The second device demonstrates 'deep' (~1\\mu m) implantation of individual NV centers into pre-fabricated diamond nanowire. The high single photon flux of the nanowire geometry, combined with the low background fluorescence of the ultrapure diamond, allows us to sustain strong photon anti-bunching even at high pump powers.

Birgit J. M. Hausmann; Thomas M. Babinec; Jennifer T. Choy; Jonathan S. Hodges; Sungkun Hong; Irfan Bulu; A. Yacoby; M. D. Lukin; Marko Lon?ar

2010-09-21

291

Low energy implantation of boron with decaborane ions  

NASA Astrophysics Data System (ADS)

Implantation of molecular ions of decaborane (B10H14) is an alternative path to ultra shallow doping of Si with B ions of very low energy (<1 keV). Because of their mass, the molecular ions with an energy an order of magnitude larger than an energy of B+ monomer ions achieve the same implantation depth. In addition, the molecular ions transport ten times more B per unit charge. To assess the feasibility of this approach, the properties of the decaborane ion beams with energies from 2 to 10 keV were examined. The ions were generated in an electron impact ionization source and transported to a sample chamber through a 2.5 m long beam line with an analyzing magnet. Experiments with electrostatic beam deflection show that the large ions survive the transport in the implanter environment and that neutralization is negligible. Si samples were implanted with decaborane ions and the implanted dose measured by current integration was compared with the amount of retained 11B obtained by nuclear reaction analysis. The retained dose was found to be larger for decaborane ions, which may be attributed to a sputtering yield of Si, smaller than for low energy B+ ions. Development of ion sources capable of generating decaborane ion beams has reached the stage where batches of wafers can be implanted. The implanted B profiles and electrical characteristics of test MOS transistors fabricated using implantation with decaborane ions and B+ and BF2+ ions of equivalent energy were found to be very similar. The results confirm the potential of decaborane ion beams as an alternative technology for manufacturing of ultra shallow p-type junctions in Si. More research is needed to fully understand the effects of cluster ions in semiconductors.

Sosnowski, Marek

2001-07-01

292

Chapter 29. The Retinal Implant Project The Retinal Implant Project  

E-print Network

. At the completion of the surgery, the whole implant was covered by the conjunctiva. No complications were observed that it was functional following the surgery. In May of 2008, we successfully repeated this surgery twice more. An ab during the surgeries, although some extrusion of the implant through the conjunctiva #12;Chapter 29

293

Effects of implantation of decaborane ions in silicon  

NASA Astrophysics Data System (ADS)

The next generations of Si microelectronic devices will require ultra shallow p-type junctions formed by implantation of B ions with energies below 1 keV, at which available beam currents are severely limited by space charge effects. To solve this problem, decaborane (B 10H14) cluster ion implantation has been suggested as an attractive alternative to conventional B implants, because one decaborane ion implants ten B atoms simultaneously and each of the B atoms only carries approximately 1/11 of the total ion energy. Thus the same implantation depth and dose as with monomer B ions can be obtained using decaborane ions but with 10 times less charge and ten times higher energy. In this dissertation research, various effects of implantation of decaborane cluster ions in silicon were studied, using an experimental ion implanter in the Ion Beam and Thin Film Research Laboratory at NJIT. Secondary Ion Mass Spectrometry (SIMS) depth profiles of boron and hydrogen in decaborane-implanted samples were measured before and after thermal activation annealing and compared to that in the control samples. Shallow p-type junction could be achieved with decaborane implantation. The co-implanted hydrogen diffused out almost entirely after annealing and hence is expected to have a negligible effect on the device performance. Transient enhanced diffusion (TED) of B atoms in Si implanted with mass analyzed decaborane ions of three energies were measured and compared to that of B atoms in Si implanted with B+ ions of equivalent B energy and dose. The results demonstrated that implantation of B with decaborane cluster ions led to essentially the same amount of TED of B in Si as that in Si implanted with atomic B+ ions of the equivalent energy and dose. The sputtering yields of Si with B in the form of decaborane clusters were measured and compared to those for boron monomer ions, estimated using an empirical formula. The surface morphology of amorphous Si, crystalline Si and Ta film irradiated with energetic decaborane ions and argon ions were studied using Atomic Force Microscopy (AFM). Results of surface roughness and Power Spectral Density (PSD) analysis show that decaborane cluster ions smooth rather than roughen these surfaces. Molecular Dynamics (MD) simulations have been performed to compare impact effects on Si target by B monomers and B10 clusters at the same energy per B atom. B depth profiles were found to be similar for B atoms implanted with B10 clusters and with B monomers. The crater formation, a unique feature of cluster impacts, was also observed on the Si surface impacted by a B10 cluster. The calculated sputtering yield of Si (the number of ejected Si atoms per incident B) was much larger with B10 clusters than with B monomers and also larger than the experimental values. The results of this research confirm that decaborane implantation is a viable alternative to low energy B implantation for ultra shallow p-type junction formation. These results also contribute to the knowledge base of the technology of ultra shallow B doping in CMOS devices and will help to better understand cluster-solid interactions in general.

Li, Cheng

294

Additive manufacturing: From implants to organs.  

PubMed

Additive manufacturing (AM) constructs 3D objects layer by layer under computer control from 3D models. 3D printing is one example of this kind of technology. AM offers geometric flexibility in its products and therefore allows customisation to suit individual needs. Clinical success has been shown with models for surgical planning, implants, assistive devices and scaffold-based tissue engineering. The use of AM to print tissues and organs that mimic nature in structure and function remains an elusive goal, but has the potential to transform personalised medicine, drug development and scientific understanding of the mechanisms of disease.  PMID:25214247

Douglas, Tania S

2014-06-01

295

Norplant implants in Ethiopia.  

PubMed

This is a cross-sectional study involving 364 clients who have had Norplant implants insertion for contraception at the Gandhi Memorial Hospital (GMH) during the second half of 1994. It was part of the pilot project designed to introduce Norplant in Ethiopia after evaluating the safety, efficacy, tolerance, acceptability and reversibility of the method. The vast majority of the clients were found to be married, housewives, multiparae, relatively educated, urban dwellers, Christian by faith and in their reproductive age group with a mean age of 27.9 +/- 5.7 years. A significant number of them used one or more types of contraceptive methods prior to their switch to Norplant (P < 0.05). A third of the patients were lactating at the time of the Norplant insertion. The time taken to insert the implants was 12.5 +/- 4.3 minutes. The mean duration since the insertion is computed to be 25.3 +/- 4.2 months. Their main source of information was from the medical personnel. The acceptability and continuation rate of the method was 93.9% and 95.1%, respectively. The fertility-reversibility among those who desired to have childbirth was achieved in 72.3% and 84.1% at one and two years, respectively. Adverse effects of Norplant were registered in a quarter of the study population and included abnormal menstruation, headache, weight changes and pain at the site of implantation. These were not influenced by age, body weight, parity, duration of usage of the method, blood pressure patterns and previous use of contraception (P > 0.05). We have not encountered any method failure in the last 30 months. The study concludes that Norplant is safe, effective, acceptable, and reversible long-term birth control method which can be used in our setting in parallel with other available options. PMID:9299831

Argina, H; Lukman, H Y

1997-04-01

296

Broad beam ion implanter  

DOEpatents

An ion implantation device for creating a large diameter, homogeneous, ion beam is described, as well as a method for creating same, wherein the device is characterized by extraction of a diverging ion beam and its conversion by ion beam optics to an essentially parallel ion beam. The device comprises a plasma or ion source, an anode and exit aperture, an extraction electrode, a divergence-limiting electrode and an acceleration electrode, as well as the means for connecting a voltage supply to the electrodes. 6 figs.

Leung, K.N.

1996-10-08

297

[A Roman orbital implant?].  

PubMed

During an excavation in Regensburg/Germany the skeleton of an approximately 20-year-old Roman man was found who was buried in the 3rd/4th century after Christ. A "stone" was found which fitted into the left orbit precisely. After a thorough investigation of the "stone" and with the ophthalmohistorical literature in mind an orbital "implant" as well as a petrified medical paste ("Kollyrium") could be ruled out almost with certainty. Possibly the "stone" served another medical purpose or was used for protection of the eye. PMID:23011607

Rohrbach, J M; Harbeck, M; Holzhauser, P; Tekeva-Rohrbach, C I; Mach, M; Codreanu-Windauer, S

2012-11-01

298

Production of Endohedral Fullerenes by Ion Implantation  

SciTech Connect

The empty interior cavity of fullerenes has long been touted for containment of radionuclides during in vivo transport, during radioimmunotherapy (RIT) and radioimaging for example. As the chemistry required to open a hole in fullerene is complex and exceedingly unlikely to occur in vivo, and conformational stability of the fullerene cage is absolute, atoms trapped within fullerenes can only be released during extremely energetic events. Encapsulating radionuclides in fullerenes could therefore potentially eliminate undesired toxicity resulting from leakage and catabolism of radionuclides administered with other techniques. At the start of this project however, methods for production of transition metal and p-electron metal endohedral fullerenes were completely unknown, and only one method for production of endohedral radiofullerenes was known. They therefore investigated three different methods for the production of therapeutically useful endohedral metallofullerenes: (1) implantation of ions using the high intensity ion beam at the Oak Ridge National Laboratory (ORNL) Surface Modification and Characterization Research Center (SMAC) and fullerenes as the target; (2) implantation of ions using the recoil energy following alpha decay; and (3) implantation of ions using the recoil energy following neutron capture, using ORNL's High Flux Isotope Reactor (HFIR) as a thermal neutron source. While they were unable to obtain evidence of successful implantation using the ion beam at SMAC, recoil following alpha decay and neutron capture were both found to be economically viable methods for the production of therapeutically useful radiofullerenes. In this report, the procedures for preparing fullerenes containing the isotopes {sup 212}Pb, {sup 212}Bi, {sup 213}Bi, and {sup 177}Lu are described. None of these endohedral fullerenes had ever previously been prepared, and all of these radioisotopes are actively under investigation for RIT. Additionally, the chemistry for derivatizing the radiofullerenes for water-solubility and a method for removing exohedral radionuclides are reported. The methods and chemistry developed during this CRADA are the crucial first steps for the development of fullerenes as a method superior to existing technologies for in vivo transport of radionuclides.

Diener, M.D.; Alford, J. M.; Mirzadeh, S.

2007-05-31

299

The optimal design of an implant to improve bone quality of implant surroundings based on stress analysis  

NASA Astrophysics Data System (ADS)

Research on how implant surface shape contributes to long-term stability after implantation is important in the field of orthopaedics. In particular, technology that controls various bone quality parameters and voluntary bone inducement in implant surroundings should be developed for the next generation of implants and this will improve the patient's quality of life (QOL). For this research, we focused on the inducement of the appropriate alignment for biological apatite (BAp) crystallites and related collagen (Col.) fibres as a bone quality parameter. In this study, we predicted that when stress is applied to bone, the BAp/Col. preferential alignment can be formed if osteocytes are in an environment that is aligned with the principle stress vector. We tested this idea by introducing grooves in the principal stress direction on the surface of an implant. This work thus analyzes the effect of stress transmission by a load at the proximal femur on the bone inside and near the grooves by using mechanical simulation in which groove angles can be changed on the implant surface. Coordinate data from the mechanical simulation of the combined bone/implant environment was verified against the coordinate data obtained by CT scans of actual canine bone. Results suggest that the tendency of stress transmission differs depending on the position and angle of the grooves and based on a vector diagram of the maximum and minimum principal stresses. The simulation was able to predict bone dynamics in vivo and enabled a best design of an implant to control the BAp/Col. alignment as an index of bone quality.

Noyama, Yoshihiro; Nagayama, Noriyuki; Kuramoto, Koichi; Nakano, Takayoshi

2009-05-01

300

Implant fixation by bone ingrowth  

Microsoft Academic Search

The term osseointegration referred originally to an intimate contact of bone tissue with the surface of a titanium implant; the term bone ingrowth refers to bone formation within an irregular (beads, wire mesh, casting voids, cut grooves) surface of an implant. The section dealing with the historical background describes the development of macroporous, microporous, and textured surfaces with an emphasis

H. Kienapfel; C. Sprey; A. Wilke; P. Griss

1999-01-01

301

Porous metal for orthopedics implants  

PubMed Central

Summary Porous metal has been introduced to obtain biological fixation and improve longevity of orthopedic implants. The new generation of porous metal has intriguing characteristics that allows bone healing and high osteointegration of the metallic implants. This article gives an overview about biomaterials properties of the contemporary class of highly porous metals and about the clinical use in orthopaedic surgery. PMID:24133527

Matassi, Fabrizio; Botti, Alessandra; Sirleo, Luigi; Carulli, Christian; Innocenti, Massimo

2013-01-01

302

Implant fixation by bone ingrowth.  

PubMed

The term osseointegration referred originally to an intimate contact of bone tissue with the surface of a titanium implant; the term bone ingrowth refers to bone formation within an irregular (beads, wire mesh, casting voids, cut grooves) surface of an implant. The section dealing with the historical background describes the development of macroporous, microporous, and textured surfaces with an emphasis on the evolution of porous and textured metal surfaces. The principal requirements for osseointegration and bone ingrowth are systematically reviewed as follows: i) the physiology of osseointegration and bone ingrowth, including biomaterial biocompatibility with respect to cellular and matrix response at the interface; ii) the implant surface geometry characteristics; iii) implant micromotion and fixation modes; and iv) the implant-bone interface distances. Based on current methods of bone ingrowth assessment, this article comparatively reviews and discusses the results of experimental studies with the objective of determining local and systemic factors that enhance bone ingrowth fixation. PMID:10220191

Kienapfel, H; Sprey, C; Wilke, A; Griss, P

1999-04-01

303

Airport detectors and orthopaedic implants.  

PubMed

As a result of the rising threats of terrorism, airport security has become a major issue. Patients with orthopaedic implants are concerned that they may activate alarms at airport security gates. A literature overview showed that the activation rate of the alarm by hand-held detectors is higher than for arch detectors (100% versus 56%). Arch detection rate has significantly increased from 0% before 1995 up to 83.3% after 1994. Reported factors which influence detection rates are implant mass, implant combinations, implant volume, transfer speed, side of implant, detector model, sensitivity settings, material and tissue masking. Detection rate has been improved by more sensitive devices and improved filter software. Doctors should be able to objectively inform patients. A form is presented which will easily inform the airport security staff. PMID:16184989

van der Wal, Bart C H; Grimm, Bernd; Heyligers, Ide C

2005-08-01

304

Hydrogen Implants for Layer Exfoliation  

NASA Astrophysics Data System (ADS)

Researchers at Corning Incorporated have developed a process whereby single crystal silicon thin films are transferred onto a flat panel display glass substrate using hydrogen ion implantation. The energy of the implant controls the effective exfoliation thickness, agreeing well with SRIM calculations, while the hydrogen ion dose controls the size of the platelets formed. The ion dose was found to influence the final void defect count in exfoliated films. Finally, the ion beam and ion implant end-station cooling characteristics were investigated. These parameters control the effective implant heat load generated during ion beam processing. The temperature at which exfoliation occurs during an exfoliation heat cycle was found to be inversely proportional to the hydrogen ion dose when the temperature during ion implantation is <100 °C. The most sensitive exfoliation temperature to ion dose dependence was observed for cooler implants, i.e. <35 °C. Data indicates that at the minimum exfoliation dose the exfoliation temperature is reduced significantly by increasing the implant heat generated during ion beam processing. Higher hydrogen doses than the minimum required for exfoliation exhibit only a small exfoliation temperature variation with ion dose. By optimizing the implant heat load generated during ion beam processing it is observed that the efficiency of the exfoliation process is also enhanced. Implant temperatures of 150 to 160 °C were found to further reduce the minimum implant dose required for exfoliation by an additional 5%, as verified by calorimetric measurements. These results enable us to further conclude that hydrogen out-diffusion is not significant in this process.

Cherekdjian, S.; Couillard, J. G.; Wilcox, C.

2011-01-01

305

Implantation of Vascular Grafts Lined with Genetically Modified Endothelial Cells  

NASA Astrophysics Data System (ADS)

The possibility of using the vascular endothelial cell as a target for gene replacement therapy was explored. Recombinant retroviruses were used to transduce the lacZ gene into endothelial cells harvested from mongrel dogs. Prosthetic vascular grafts seeded with the genetically modified cells were implanted as carotid interposition grafts into the dogs from which the original cells were harvested. Analysis of the graft 5 weeks after implantation revealed genetically modified endothelial cells lining the luminal surface of the graft. This technology could be used in the treatment of atherosclerosis disease and the design of new drug delivery systems.

Wilson, James M.; Birinyi, Louis K.; Salomon, Robert N.; Libby, Peter; Callow, Allan D.; Mulligan, Richard C.

1989-06-01

306

A Retrospective Analysis of Ruptured Breast Implants  

PubMed Central

Background Rupture is an important complication of breast implants. Before cohesive gel silicone implants, rupture rates of both saline and silicone breast implants were over 10%. Through an analysis of ruptured implants, we can determine the various factors related to ruptured implants. Methods We performed a retrospective review of 72 implants that were removed for implant rupture between 2005 and 2014 at a single institution. The following data were collected: type of implants (saline or silicone), duration of implantation, type of implant shell, degree of capsular contracture, associated symptoms, cause of rupture, diagnostic tools, and management. Results Forty-five Saline implants and 27 silicone implants were used. Rupture was diagnosed at a mean of 5.6 and 12 years after insertion of saline and silicone implants, respectively. There was no association between shell type and risk of rupture. Spontaneous was the most common reason for the rupture. Rupture management was implant change (39 case), microfat graft (2 case), removal only (14 case), and follow-up loss (17 case). Conclusions Saline implants have a shorter average duration of rupture, but diagnosis is easier and safer, leading to fewer complications. Previous-generation silicone implants required frequent follow-up observation, and it is recommended that they be changed to a cohesive gel implant before hidden rupture occurs. PMID:25396188

Baek, Woo Yeol; Lew, Dae Hyun

2014-01-01

307

Or Th Pr Au Cr Two-Year Master Program (120 ECTS)  

E-print Network

focus in sustainable car technologies Compulsory courses Module 1 : Vehicle dynamics and safety MECA0492-2 Vehicle dynamics (english language) - Pierre DUYSINX Q1 30 20 - 4 MECA0493-2 Vehicle aerodynamics (english

Wolper, Pierre

308

Characteristics of planar n-p junction diodes made by double-implantations into 4H-SiC  

Microsoft Academic Search

Double implantation technology consisting of deep-range acceptor followed by shallow-range donor implantation was used to fabricate planar n+-p junction diodes in 4H-SiC. Either Al or B was used as the acceptor species and N as the donor species with all implants performed at 700°C and annealed at 1650°C with an AlN encapsulant. The diodes were characterized for their current-voltage (I-V)

Jesse B. Tucker; Mulpuri V. Rao; Nicolas A. Papanicolaou; Jeff Mittereder; Ahmed Elasser; A. William Clock; Mario Ghezzo; O. W. Holland; Kenneth A. Jones

2001-01-01

309

Observation of the Inverse CottonMouton E#ect Andrei BenAmar Baranga, 1,# Remy Battesti, 1 Mathilde Fouche, 1,2,3 Carlo Rizzo, 1,2,3,#  

E-print Network

the dependence of the measured e#ect on the laser power density and polarization, and on the static external. In 1987 Zon et al. reported the measurement of a magnetization of a magnetic film induced by a laser beam the de­ pendence of the measured e#ect on the laser energy and polarization, and on the external magnetic

310

The effect of plasma chemical oxidation of titanium alloy on bone-implant contact in rats.  

PubMed

Many different technologies have been used to enhance osseointegration in orthopaedic and dental implant surgery. Hydroxyapatite coatings, pure or in combination with growth factors or bisphosphonates, showed improved osseointegration of titanium alloy implants. We choose a different approach to enhance osseointegration: plasma chemical oxidation was used to modify the surface of titanium alloy implants. This technique converts the nm-thin natural occurring titanium oxide layer on an implant to a 4 ?m thick ceramic coating (TiOB surface). Bioactive TiOB surfaces have a macroporous structure and were loaded with calcium and phosphorus, while bioinert TiOB surfaces are smooth. A rat tibial model with bilateral placement of titanium alloy implants was employed to analyze the bone response to TiOB surfaces in vivo. 64 rats were randomly assigned to four groups of implants: (1) titanium alloy (control), (2) titanium alloy, type III anodization, (3) bioinert TiOB surface and (4) bioactive TiOB surface. Mechanical fixation, peri-implant-bone area and bone contact were evaluated by pull-out tests and histology at three and eight weeks. Shear strength and bone contact at eight weeks were significantly increased in the bioactive TiOB group compared to all other groups. The results of plasma chemical oxidation in a rat model showed that the bioactive TiOB surface has a positive effect on implant anchorage by enhancing the bone-implant contact in normal bone. PMID:21840591

Diefenbeck, Michael; Mückley, Thomas; Schrader, Christian; Schmidt, Jürgen; Zankovych, Sergiy; Bossert, Jörg; Jandt, Klaus D; Faucon, Mathilde; Finger, Ulrich

2011-11-01

311

Wireless microsensor network solutions for neurological implantable devices  

NASA Astrophysics Data System (ADS)

The design and development of wireless mocrosensor network systems for the treatment of many degenerative as well as traumatic neurological disorders is presented in this paper. Due to the advances in micro and nano sensors and wireless systems, the biomedical sensors have the potential to revolutionize many areas in healthcare systems. The integration of nanodevices with neurons that are in communication with smart microsensor systems has great potential in the treatment of many neurodegenerative brain disorders. It is well established that patients suffering from either Parkinson"s disease (PD) or Epilepsy have benefited from the advantages of implantable devices in the neural pathways of the brain to alter the undesired signals thus restoring proper function. In addition, implantable devices have successfully blocked pain signals and controlled various pelvic muscles in patients with urinary and fecal incontinence. Even though the existing technology has made a tremendous impact on controlling the deleterious effects of disease, it is still in its infancy. This paper presents solutions of many problems of today's implantable and neural-electronic interface devices by combining nanowires and microelectronics with BioMEMS and applying them at cellular level for the development of a total wireless feedback control system. The only device that will actually be implanted in this research is the electrodes. All necessary controllers will be housed in accessories that are outside the body that communicate with the implanted electrodes through tiny inductively-coupled antennas. A Parkinson disease patient can just wear a hat-system close to the implantable neural probe so that the patient is free to move around, while the sensors continually monitor, record, transmit all vital information to health care specialist. In the event of a problem, the system provides an early warning to the patient while they are still mobile thus providing them the opportunity to react and trigger the feed back system or contact a point-of-care office that can remotely control the implantable system. The remote monitoring technology can be adaptable to EEG monitoring of children with epilepsy, implantable cardioverters/defibrillators, pacemakers, chronic pain management systems, treatment for sleep disorders, patients with implantable devices for diabetes. In addition, the development of a wireless neural electronics interface to detect, transmit and analyze neural signals could help patients with spinal injuries to regain some semblance of mobile activity.

Abraham, Jose K.; Whitchurch, Ashwin; Varadan, Vijay K.

2005-05-01

312

Chip-scale hermetic feedthroughs for implantable bionics.  

PubMed

Most implantable medical devices such as cochlear implants and visual prostheses require protection of the stimulating electronics. This is achieved by way of a hermetic feedthrough system which typically features three important attributes: biocompatibility with the human body, device hermeticity and density of feedthrough conductors. On the quest for building a visual neuroprosthesis, a high number of stimulating channels is required. This has encouraged new technologies with higher rates of production yield and further miniaturization. An Al(2)O(3) based feedthrough system has been developed comprising up to 20 platinum feedthroughs per square millimeter. Ceramics substrates are shown to have leak rates below 1 × 10(-12) atm × cc/s, thus exceeding the resolution limits of most commercially available leak detectors. A sheet resistance of 0.05 ? can be achieved. This paper describes the design, fabrication process and hermeticity testing of high density feedthroughs for use in neuroprosthetic implants. PMID:22255880

Guenther, Thomas; Dodds, Christopher W D; Lovell, Nigel H; Suaning, Gregg J

2011-01-01

313

Emerging Synergy between Nanotechnology and Implantable Biosensors: A Review  

PubMed Central

The development of implantable biosensors for continuous monitoring of metabolites is an area of sustained scientific and technological interest. On the other hand, nanotechnology, a discipline which deals with the properties of materials at the nanoscale, is developing as a potent tool to enhance the performance of these biosensors. This article reviews the current state of implantable biosensors, highlighting the synergy between nanotechnology and sensor performance. Emphasis is placed on the electrochemical method of detection in light of its widespread usage and substantial nanotechnology-based improvements in various aspects of electrochemical biosensor performance. Finally, issues regarding toxicity and biocompatibility of nanomaterials, along with future prospects for the application of nanotechnology in implantable biosensors, are discussed. PMID:20042326

Vaddiraju, Santhisagar; Tomazos, Ioannis; Burgess, Diane J; Jain, Faquir C; Papadimitrakopoulos, Fotios

2010-01-01

314

Energy Efficiency and Reliability in Wireless Biomedical Implant Systems  

E-print Network

The use of wireless implant technology requires correct delivery of the vital physiological signs of the patient along with the energy management in power-constrained devices. Toward these goals, we present an augmentation protocol for the physical layer of the Medical Implant Communications Service (MICS) with focus on the energy efficiency of deployed devices over the MICS frequency band. The present protocol uses the rateless code with the Frequency Shift Keying (FSK) modulation scheme to overcome the reliability and power cost concerns in tiny implantable sensors due to the considerable attenuation of propagated signals across the human body. In addition, the protocol allows a fast start-up time for the transceiver circuitry. The main advantage of using rateless codes is to provide an inherent adaptive duty-cycling for power management, due to the flexibility of the rateless code rate. Analytical results demonstrate that an 80% energy saving is achievable with the proposed protocol when compared to the IE...

Abouei, Jamshid; Plataniotis, Konstantinos N; Pasupathy, Subbarayan

2011-01-01

315

Implantable Electrical Vesical Stimulator  

PubMed Central

Considerable interest has been shown recently in electrical stimulation of the incompetent urinary bladder. Two types of bladder stimulation have been attempted in dogs and in humans: (a) stimulation of nervi erigentes and (b) direct stimulation of the detrusor urinae muscle. After several years of animal experimentation, a vesical stimulator, built on a new electronic principle, was implanted successfully in a paraplegic patient who has a complete post-traumatic lower motor neuron lesion. The stimulator has been working satisfactorily since November 1965. This stimulator could eventually also be used in purely sensory sacral lesions, in well-selected incomplete lower motor neuron lesions, and in flaccid detrusors of the myogenic type. A review of the literature up to the time of this report shows only a few encouraging but incomplete results in humans. The techniques and the complexities involved in this problem are discussed. ImagesFig. 1Fig. 3Fig. 5 PMID:5923472

Susset, J. G.; Boctor, Z. N.; Rosario, F.; Rabinovitch, H.; Nagler, B.; MacKinnon, K. J.

1966-01-01

316

Percutaneous Pulmonary Valve Implantation  

PubMed Central

Pulmonary regurgitation (PR) is a frequent sequelae after repair of tetralogy of Fallot, pulmonary atresia, truncus arteriosus, Rastelli and Ross operation. Due to patient growth and conduit degeneration, these conduits have to be changed frequently due to regurgitation or stenosis. However, morbidity is significant in these repeated operations. To prolong conduit longevity, bare-metal stenting in the right ventricular outflow tract (RVOT) obstruction has been performed. Stenting the RVOT can reduce the right ventricular pressure and symptomatic improvement, but it causes PR with detrimental effects on the right ventricle function and risks of arrhythmia. Percutaneous pulmonary valve implantation has been shown to be a safe and effective treatment for patients with pulmonary valve insufficiency, or stenotic RVOTs. PMID:23170091

Lee, Hyoung-Doo

2012-01-01

317

Ion-implanted laser annealed silicon solar cells  

NASA Technical Reports Server (NTRS)

Development of low cost solar cells fabrication technology is being sponsored by NASA JPL as part of the Low Cost Solar Array Project (LSA). In conformance to Project requirements ion implantation and laser annealing were evaluated as junction formation techniques offering low cost-high throughput potential. Properties of cells fabricated utilizing this technology were analyzed by electrical, transmission electron microscopy, Rutherford backscattering and secondary ion mass spectrometry techniques. Tests indicated the laser annealed substrates to be damage free and electrically active. Similar analysis of ion implanted furnace annealed substrates revealed the presence of residual defects in the form of dislocation lines and loops with substantial impurity redistribution evident for some anneal temperature/time regimes. Fabricated laser annealed cells exhibited improved spectral response and conversion efficiency in comparison to furnace annealed cells. An economic projection for LSA indicates a potential for considerable savings from laser annealing technology.

Katzeff, J. S.

1980-01-01

318

Occlusion on oral implants: current clinical guidelines.  

PubMed

Proper implant occlusion is essential for adequate oral function and the prevention of adverse consequences, such as implant overloading. Dental implants are thought to be more prone to occlusal overloading than natural teeth because of the loss of the periodontal ligament, which provides shock absorption and periodontal mechanoreceptors, which provide tactile sensitivity and proprioceptive motion feedback. Although many guidelines and theories on implant occlusion have been proposed, few have provided strong supportive evidence. Thus, we performed a narrative literature review to ascertain the influence of implant occlusion on the occurrence of complications of implant treatment and discuss the clinical considerations focused on the overloading factors at present. The search terms were 'dental implant', 'dental implantation', 'dental occlusion' and 'dental prosthesis'. The inclusion criteria were literature published in English up to September 2013. Randomised controlled trials (RCTs), prospective cohort studies and case-control studies with at least 20 cases and 12 months follow-up interval were included. Based on the selected literature, this review explores factors related to the implant prosthesis (cantilever, crown/implant ratio, premature contact, occlusal scheme, implant-abutment connection, splinting implants and tooth-implant connection) and other considerations, such as the number, diameter, length and angulation of implants. Over 700 abstracts were reviewed, from which more than 30 manuscripts were included. We found insufficient evidence to establish firm clinical guidelines for implant occlusion. To discuss the ideal occlusion for implants, further well-designed RCTs are required in the future. PMID:25284468

Koyano, K; Esaki, D

2015-02-01

319

Surgical Complications After Implant Placement.  

PubMed

Placement of dental implants in the maxillofacial region is routine and considered safe. However, as with any surgical procedure, complications occur. Many issues that arise at surgery can be traced to the preoperative evaluation of the patient and assessment of the underlying anatomy. In this article, the authors review some common and uncommon complications that can occur during and shortly after implant placement. The emphasis of each section is on the management and prevention of complications that may occur during implant placement. PMID:25434559

Camargo, Igor Batista; Van Sickels, Joseph E

2015-01-01

320

MO/~ECt3LAaPHYSICS,1993, VOL. 79, No. 2, 245-251 Far-infrared vibration-rotation-tunnelling spectroscopy of ArDCI  

E-print Network

MO/~ECt3LAaPHYSICS,1993, VOL. 79, No. 2, 245-251 Far-infrared vibration of the ArDC1 complex have been observed by tunable far-infrared laser spectroscopyin a supersonic planar jet Ltd. #12;246 M.J. Elrod et al. (denoted H6(3)) [5] solely from direct far-infrared (FIR) measurements

Cohen, Ronald C.

321

ReProTool Version 2.0: Re-Engineering Academic Curriculum Using Learning Outcomes, ECTS and Bologna Process Concepts  

ERIC Educational Resources Information Center

Purpose: The purpose of this paper is to present ReProTool Version 2.0, a software tool that is used for the European Credit Transfer System (ECTS) and the Bologna Process re-engineering of academic programmes. The tool is the result of an 18 months project (February 2012-July 2013) project, co-financed by the European Regional Development Fund…

Pouyioutas, Philippos; Gjermundrod, Harald; Dionysiou, Ioanna

2012-01-01

322

E ect of the reservoir size on gas adsorption in inhomogeneous porous media E. Kierlik, 1 J. Puibasset, 2 and G. Tarjus 1  

E-print Network

E#11;ect of the reservoir size on gas adsorption in inhomogeneous porous media E. Kierlik, 1 J of the reservoir on the adsorption isotherms of a uid in disordered or inhomogeneous mesoporous solids. We, the uid inside the porous solid exchanges matter with a reservoir of gas that is at the same temperature

Recanati, Catherine

323

Proc. of the 5 th Int. Conference on Digital Audio E#ects (DAFx02), Hamburg, Germany, September 2628, 2002 DOPPLER SIMULATION AND THE LESLIE  

E-print Network

, followed by a description of a Leslie simulator. 2. THE DOPPLER EFFECT In the real world, a Doppler shift­28, 2002 DOPPLER SIMULATION AND THE LESLIE Julius Smith, Stefania Serafin Center for Computer Research@uaudio.com dpberner@uaudio.com ABSTRACT An e#cient algorithm for simulating the Doppler e#ect us­ ing interpolating

Smith III, Julius Orion

324

Eff ects of Elevated Atmospheric CO 2 on Invasive Plants: Comparison of Purple and Yellow Nutsedge (Cyperus rotundus L. and C. esculentus L.)  

Microsoft Academic Search

Th e rise in atmospheric CO 2 concentration coupled with its direct, often positive, eff ect on the growth of plants raises the question of the response of invasive plants to elevated atmospheric CO2 levels. Response of two invasive weeds (purple nutsedge (Cyperus rotundus L.) and yellow nutsedge ( Cyperus esculentus L.)) to CO2 enrichment was tested. Plants were exposed

H. H. Rogers; G. B. Runion; A. J. Price; H. A. Torbert USDA-ARS

325

Time to start writing a manuscript for your thesis work? Welcome to the PhD course `Writing Scientific Papers' (5 ECTS) starting  

E-print Network

Scientific Papers' (5 ECTS) starting Friday 27 September 2013! Last day to register for the course the basics in how to write a scientific paper for submission to an international scientific journal. Content students present and discuss their comments, questions and suggestions. Examination: Participation

326

Accidental Implant Screwdriver Ingestion: A Rare Complication during Implant Placement  

PubMed Central

One of the complications during a routine dental implant placement is accidental ingestion of the implant instruments, which can happen when proper precautions are not taken. Appropriate radiographs should be taken to locate the correct position of foreign body; usually the foreign body passes asymptomatically from gastrointestinal tract but sometimes it may lead to intestinal obstruction, perforations and impactions. The aim of this article is to report accidental ingestion of 19 mm long screw driver by a senile patient.

Jain, Anshul; Baliga, Shridhar D

2014-01-01

327

Elastic relaxation in patterned and implanted strained silicon on insulator  

NASA Astrophysics Data System (ADS)

Mechanical relaxations of strained silicon on insulator (sSOI) nanostructures are studied for the isolation and implantation processes used in transistor technology. Two model systems are quantitatively analyzed by grazing incidence x-ray diffraction: long etched sSOI lines of different widths and bidimensional (2D) sSi samples implanted by As/Xe ions with the same stripe geometry, the gate stack acting as an implantation mask. For sSOI lines, the strain of the initial 2D layer is conserved along the longer direction, i.e., the transport direction. Along the small direction, a large relaxation is observed especially for the smaller widths. This relaxation is almost complete for thicker samples (70 nm), whereas it is much more limited for thinner ones (10 nm). The tuning by etching/size selection of the sSOI initial biaxial stress into uniaxial stress along the transport direction should represent a great advantage for n-metal oxide semiconductor (n-MOS) devices in terms of mobility. Similar relaxation anisotropies have been observed for the implanted samples with 60 nm thickness. In this case, the relaxed small dimension of the area under the gate stack corresponds to the transport direction. This direct source/drain implantation step should therefore damage the performance of partially depleted sSOI n-MOS devices. However these relaxation phenomena should be advantageously used with new integration schemes.

Baudot, S.; Andrieu, F.; Rieutord, F.; Eymery, J.

2009-06-01

328

The design and production of Ti-6Al-4V ELI customized dental implants  

NASA Astrophysics Data System (ADS)

This paper addresses the production of customized Ti-6Al-4V ELI dental implants via electron beam melting (EBM). The melting of Ti-6Al-4V ELI powder produces implants with great biocompatibility, fi ne mechanical performance, and a high bone ingrowth potential. The EBM technology is used to produce one-component dental implants that mimic the exact shape of the patient’s tooth, replacing the traditional, three-component, “screw-like” standardized dental implants currently used. The new generation of implants provides the possibility of simplifying pre-insertion procedures leading to faster healing time, and the potential of better and stronger osseointegration, specifi cally through incorporating lattice structure design.

Chahine, Gilbert; Koike, Mari; Okabe, Toru; Smith, Pauline; Kovacevic, Radovan

2008-11-01

329

Ion implantation processing for high-speed GaAs JFETs  

SciTech Connect

GaAs Junction Field Effect Transistors (JFETs) offer a higher gate turn-on voltage, resulting in a better noise margin and reduced power dissipation, than the more widely employed GaAs MESFET. The primary reason the JFET has not been more widely used is the speed penalty associated with the gate/channel junction and corresponding gate length broadening. We present the ion implantation processes used for a self-aligned, all ion-implanted, GaAs JFET that minimizes the speed penalty for the JFET while maintaining the advantageous higher gate turn-on voltage. Process characterization of the p{sub +}-gate implant done with either Mg, Zn, or Cd along with the co-implantation of P is presented. In addition, a novel backside channel confinement technology employing ion-implanted carbon is discussed. Complete JFET device results are reported.

Zolper, J.C.; Baca, A.G.; Sherwin, M.E.; Shul, R.J.

1995-07-01

330

ANTIARRHYTHMICS VERSUS IMPLANTABLE DEFIBRILLATORS (AVID)  

EPA Science Inventory

Evaluates whether use of an implantable cardiac defibrillator (ICD) results in reduction in total mortality, when compared with conventional pharmacological therapy, in patients resuscitated from sudden cardiac death who are otherwise at very high risk of mortality from arrhythmi...

331

Minimally Invasive Penile Implant Surgery  

MedlinePLUS Videos and Cool Tools

... specialists are doing penile prosthesis cases in the United States? 00:16:27 J. FRANCOIS EID, MD: I ... should be. Do you realize that across the United States there’s 300,000 breast implants a year? Across ...

332

Cyborg Technology  

NSDL National Science Digital Library

Discussions of cyborg technology tend to be relegated to science fiction literature and TV programs like Star Trek. This Topic in Depth looks into current issues and developments in the area of cyborg technology. The first website, from the UC Santa Barbara Department of English, (1) lists a variety of resources on cyborgs, from philosophical articles and literary criticism to current scientific practices. A related area of research is brain-computer interfacing (BCI), which is described on this website from the Helsinki Institute of Technology (2). Research on neural engineering, which combines work in electrical and computer engineering, tissue engineering, materials science, and nanotechnology, is also described on this website from USC (3). The Discovery School (4) suggests this lesson on technology for grades six through eight, in which students explore how the human body uses electric signals to send messages to and from the brain, and then how the nervous system uses those signals, with the option for additional discussions regarding the potential for cyborg technology. The next website from National Public Radio (5) provides a current look at applications of cyber technology, most of which are in the area of healthcare. For example, this program reports on how "scientists make it possible for quadriplegics to control a television, play simple computer games and check e-mail... by just thinking about it." Another interesting experiment--Project Cyborg--involves the neuro-surgical implantation of a device into the median nerves of this researchers' left arm and is described this website (6).

333

Implantable Cardioverter Defibrillators. Prophylactic Use  

PubMed Central

Executive Summary Objective The use of implantable cardiac defibrillators (ICDs) to prevent sudden cardiac death (SCD) in patients resuscitated from cardiac arrest or documented dangerous ventricular arrhythmias (secondary prevention of SCD) is an insured service. In 2003 (before the establishment of the Ontario Health Technology Advisory Committee), the Medical Advisory Secretariat conducted a health technology policy assessment on the prophylactic use (primary prevention of SCD) of ICDs for patients at high risk of SCD. The Medical Advisory Secretariat concluded that ICDs are effective for the primary prevention of SCD. Moreover, it found that a more clearly defined target population at risk for SCD that would be likely to benefit from ICDs is needed, given that the number needed to treat (NNT) from recent studies is 13 to 18, and given that the per-unit cost of ICDs is $32,000, which means that the projected cost to Ontario is $770 million (Cdn). Accordingly, as part of an annual review and publication of more recent articles, the Medical Advisory Secretariat updated its health technology policy assessment of ICDs. Clinical Need Sudden cardiac death is caused by the sudden onset of fatal arrhythmias, or abnormal heart rhythms: ventricular tachycardia (VT), a rhythm abnormality in which the ventricles cause the heart to beat too fast, and ventricular fibrillation (VF), an abnormal, rapid and erratic heart rhythm. About 80% of fatal arrhythmias are associated with ischemic heart disease, which is caused by insufficient blood flow to the heart. Management of VT and VF with antiarrhythmic drugs is not very effective; for this reason, nonpharmacological treatments have been explored. One such treatment is the ICD. The Technology An ICD is a battery-powered device that, once implanted, monitors heart rhythm and can deliver an electric shock to restore normal rhythm when potentially fatal arrhythmias are detected. The use of ICDs to prevent SCD in patients resuscitated from cardiac arrest or documented dangerous ventricular arrhythmias (secondary prevention) is an insured service in Ontario. Primary prevention of SCD involves identification of and preventive therapy for patients who are at high risk for SCD. Most of the studies in the literature that have examined the prevention of fatal ventricular arrhythmias have focused on patients with ischemic heart disease, in particular, those with heart failure (HF), which has been shown to increase the risk of SCD. The risk of HF is determined by left ventricular ejection fraction (LVEF); most studies have focused on patients with an LVEF under 0.35 or 0.30. While most studies have found ICDs to reduce significantly the risk for SCD in patients with an LVEF less than 0.35, a more recent study (Sudden Cardiac Death in Heart Failure Trial [SCD-HeFT]) reported that patients with HF with nonischemic heart disease could also benefit from this technology. Based on the generalization of the SCD-HeFT study, the Centers for Medicare and Medicaid in the United States recently announced that it would allocate $10 billion (US) annually toward the primary prevention of SCD for patients with ischemic and nonischemic heart disease and an LVEF under 0.35. Review Strategy The aim of this literature review was to assess the effectiveness, safety, and cost effectiveness of ICDs for the primary prevention of SCD. The standard search strategy used by the Medical Advisory Secretariat was used. This included a search of all international health technology assessments as well as a search of the medical literature from January 2003–May 2005. A modification of the GRADE approach (1) was used to make judgments about the quality of evidence and strength of recommendations systematically and explicitly. GRADE provides a framework for structured reflection and can help to ensure that appropriate judgments are made. GRADE takes into account a study’s design, quality, consistency, and directness in judging the quality of evidence for each outcome. The balance between benefits and harms, quality of e

2005-01-01

334

Ion implanted dielectric elastomer circuits  

NASA Astrophysics Data System (ADS)

Starfish and octopuses control their infinite degree-of-freedom arms with panache—capabilities typical of nature where the distribution of reflex-like intelligence throughout soft muscular networks greatly outperforms anything hard, heavy, and man-made. Dielectric elastomer actuators show great promise for soft artificial muscle networks. One way to make them smart is with piezo-resistive Dielectric Elastomer Switches (DES) that can be combined with artificial muscles to create arbitrary digital logic circuits. Unfortunately there are currently no reliable materials or fabrication process. Thus devices typically fail within a few thousand cycles. As a first step in the search for better materials we present a preliminary exploration of piezo-resistors made with filtered cathodic vacuum arc metal ion implantation. DES were formed on polydimethylsiloxane silicone membranes out of ion implanted gold nano-clusters. We propose that there are four distinct regimes (high dose, above percolation, on percolation, low dose) in which gold ion implanted piezo-resistors can operate and present experimental results on implanted piezo-resistors switching high voltages as well as a simple artificial muscle inverter. While gold ion implanted DES are limited by high hysteresis and low sensitivity, they already show promise for a range of applications including hysteretic oscillators and soft generators. With improvements to implanter process control the promise of artificial muscle circuitry for soft smart actuator networks could become a reality.

O'Brien, Benjamin M.; Rosset, Samuel; Anderson, Iain A.; Shea, Herbert R.

2013-06-01

335

Immediate implant placement and provisionalization using a customized anatomic temporary abutment (CATA) to achieve gingival margin stability.  

PubMed

As advances have progressed in implant dentistry, patient acceptance and long-term success rates have been on the rise. With technology ever improving, clinicians have taken treatment approaches that are aimed at a more immediate timetable as well as esthetics. The immediate implant placement and provisionalization protocol is now being applied to the anterior region. With esthetic concerns being at the forefront of implant dentistry, this case report highlights the importance of five key parameters that are related to the risk of recession following dental implant restoration in maxillary anterior sites. PMID:23991853

Ross, Scott B; Pette, Gregory A

2013-05-01

336

21 CFR 872.3970 - Interarticular disc prosthesis (interpositional implant).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Interarticular disc prosthesis (interpositional implant). 872... § 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An interarticular disc prosthesis (interpositional implant) is...

2011-04-01

337

21 CFR 886.3300 - Absorbable implant (scleral buckling method).  

Code of Federal Regulations, 2010 CFR

...false Absorbable implant (scleral buckling method). 886.3300 Section...3300 Absorbable implant (scleral buckling method). (a) Identification. An absorbable implant (scleral buckling method) is a device intended...

2010-04-01

338

[Biodeterioration and corrosion of metallic implants and prostheses].  

PubMed

The use of surgical implants and prosthetic devices to replace the original function of different components of the human biological system is a well established tradition in the history of medicine. Currently, one of the most prevalent points of view in dealing with this subject, is that of biocompatibility of materials of construction and methods of fabrication of these devices, in order to avoid negative impacts on the patient due to failure of implants through degradation mechanisms such as corrosion. This article presents a current general review of the relationship between biocompatibility and deterioration of metallic implants and prosthetic devices, emphasizing the specific forms that corrosion adopts in biological media. The historical perspective shows the consolidation of a tendency towards a more systematic study of these phenomena in recent years, as opposed to trial and error practices that used to be common before the third decade of this century. The understanding of interactions between implants and biological tissue, thus led to some of the most promising current techniques, such as the use of powder metallurgy components to optimize skeletal fixation of implants by means of interstitial bone growth into porous metallic surfaces. The review of metals and alloys currently used for the fabrication of implants shows the amplitude of available technological alternatives, as well as the multiple criteria required to make a good selection for each specific case. Applications and pros and cons of stainless steel, Cr, Ni, Co and Ti alloys, and tantalum are briefly discussed. The introduction to basic concepts of corrosion, serves as a basis for the description of the typical forms that these phenomena adopt in biological media, including pitting, crevice corrosion, fatigue-corrosion, stress corrosion, fretting corrosion, galvanic corrosion, and intergranular corrosion. This review shows that the study of interactions between biological media and metallic implants has become a well established and specific field of science. As a result of this conclusion, an interdisciplinary treatment of the subject of biodeterioration of metallic implants and prosthetic devices is proposed. In practical terms, this proposal can be understood as the integration of an expert in materials science and engineering to the medical team. Thus, quality and reliability of the implant, as well as maximization of its useful life, would be achieved through the implementation of technical specifications, accepted standards, and pertinent testing as recommended by the above mentioned expert, who will be the person of the team more able to grasp the novelties that the dynamic field of biomaterials constantly offers. PMID:8114635

López, G D

1993-01-01

339

'Fast-implantable' aortic valve implantation and concomitant mitral procedures.  

PubMed

Concomitant aortic and mitral valve replacement or concomitant aortic valve replacement and mitral repair can be a challenge for the cardiac surgeon: in particular, because of their structure and design, two bioprosthetic heart valves or an aortic valve prosthesis and a rigid mitral ring can interfere at the level of the mitroaortic junction. Therefore, when a mitral bioprosthesis or a rigid mitral ring is already in place and a surgical aortic valve replacement becomes necessary, or when older high-risk patients require concomitant mitral and aortic procedures, the new 'fast-implantable' aortic valve system (Intuity™ valve, Edwards Lifesciences, Irvine, CA, USA) can represent a smart alternative to standard aortic bioprosthesis. Unfortunately, this is still controversial (risk of interference). However, transcatheter aortic valve replacements have been performed in patients with previously implanted mitral valves or mitral rings. Interestingly, we learned that there is no interference (or not significant interference) among the standard valve and the stent valve. Consequently, we can assume that a fast-implantable valve can also be safely placed next to a biological mitral valve or next to a rigid mitral ring without risks of distortion, malpositioning, high gradient or paravalvular leak. This paper describes two cases: a concomitant Intuity™ aortic valve and bioprosthetic mitral valve implantation and a concomitant Intuity™ aortic valve and mitral ring implantation. PMID:25015540

Ferrari, Enrico; Siniscalchi, Giuseppe; Marinakis, Sotirios; Berdajs, Denis; von Segesser, Ludwig

2014-07-11

340

Behavior of AISI SAE 1020 Steel Implanted by Titanium and Exposed to Bacteria Sulphate Deoxidizer  

NASA Astrophysics Data System (ADS)

A hybrid technology to treat solid surfaces with the pulse high voltage and electric arc discharges of low pressure with a three-dimensional ion implantation technique (3DII) is applied. This technology is used to protect AISI SAE 1020 steel against a microbiological corrosion. The titanium ion implanted steel samples (coupons) are subjected to a medium of bacteria sulphate deoxidizer (BSD) which are very typical of the hydrocarbon industry and are potentially harmful for structures when are in contact with petroleum and some of its derivatives. The used technology aims to find an effective hybrid procedure to minimize the harmful effects of bacteria on AISI SAE 1020 steel. The hybrid technology efficiency of superficial titanium implantation is estimated through the measurements of the point corrosion characteristics obtained after testing both the treated and non-treated coupons. The three-dimensional surface structures of the samples are reconstructed with help of a confocal microscope.

Niño, Ely Dannier V.; Garnica, Hernán; Dugar-Zhabon, Veleriy; Castillo, Genis

2014-05-01

341

Fretting wear behavior of nitrogen ion implanted titanium alloys in bovine serum lubrication  

Microsoft Academic Search

Nitrogen ion implantation was performed on biomedical titanium alloys by using of the PBII technology to improve the surface mechanical properties for the application of artificial joints. The titanium nitride phase was characterized with X-ray photoelectron spectroscopy (XPS). The nanohardness of the titanium alloys and implanted samples were measured by using of in-situ nano-mechanical testing system (TriboIndenter). Then, the fretting

Yong Luo; Shirong Ge

2009-01-01

342

Implantable biomedical devices on bioresorbable substrates  

DOEpatents

Provided herein are implantable biomedical devices, methods of administering implantable biomedical devices, methods of making implantable biomedical devices, and methods of using implantable biomedical devices to actuate a target tissue or sense a parameter associated with the target tissue in a biological environment. Each implantable biomedical device comprises a bioresorbable substrate, an electronic device having a plurality of inorganic semiconductor components supported by the bioresorbable substrate, and a barrier layer encapsulating at least a portion of the inorganic semiconductor components. Upon contact with a biological environment the bioresorbable substrate is at least partially resorbed, thereby establishing conformal contact between the implantable biomedical device and the target tissue in the biological environment.

Rogers, John A; Kim, Dae-Hyeong; Omenetto, Fiorenzo; Kaplan, David L; Litt, Brian; Viventi, Jonathan; Huang, Yonggang; Amsden, Jason

2014-03-04

343

A Paradigm for the Development and Evaluation of Novel Implant Topologies for Bone Fixation: In Vivo Evaluation  

PubMed Central

While contemporary prosthetic devices restore some function to individuals who have lost a limb, there are efforts to develop bio-integrated prostheses to improve functionality. A critical step in advancing this technology will be to securely attach the device to remnant bone. To investigate mechanisms for establishing robust implant fixation in bone while undergoing loading, we previously used a topology optimization scheme to develop optimized orthopaedic implants and then fabricated selected designs from titanium (Ti)-alloy with selective laser sintering (SLS) technology. In the present study, we examined how implant architecture and mechanical stimulation influence osseointegration within an in vivo environment. To do this, we evaluated three implant designs (two optimized and one non-optimized) using a unique in vivo model that applied cyclic, tension/ compression loads to the implants. Eighteen (six per implant design) adult male canines had implants surgically placed in their proximal, tibial metaphyses. Experimental duration was 12 weeks; daily loading (peak load of ±22N for 1000 cycles) was applied to one of each animal’s bilateral implants for the latter six weeks. Following harvest, osseointegration was assessed by non-destructive mechanical testing, micro-computed tomography (microCT) and back-scatter scanning electron microscopy (SEM). Data revealed that implant loading enhanced osseointegration by significantly increasing construct stiffness, peri-implant trabecular morphology, and percentages of interface connectivity and bone ingrowth. While this experiment did not demonstrate a clear advantage associated with the optimized implant designs, osseointegration was found to be significantly influenced by aspects of implant architecture. PMID:22951278

Long, Jason P.; Hollister, Scott J.; Goldstein, Steven A.

2012-01-01

344

Science Goals and Overview of the Radiation Belt Storm Probes (RBSP) Energetic Particle, Composition, and Thermal Plasma (ECT) Suite on NASA's Van Allen Probes Mission  

NASA Astrophysics Data System (ADS)

The Radiation Belt Storm Probes (RBSP)-Energetic Particle, Composition, and Thermal Plasma (ECT) suite contains an innovative complement of particle instruments to ensure the highest quality measurements ever made in the inner magnetosphere and radiation belts. The coordinated RBSP-ECT particle measurements, analyzed in combination with fields and waves observations and state-of-the-art theory and modeling, are necessary for understanding the acceleration, global distribution, and variability of radiation belt electrons and ions, key science objectives of NASA's Living With a Star program and the Van Allen Probes mission. The RBSP-ECT suite consists of three highly-coordinated instruments: the Magnetic Electron Ion Spectrometer (MagEIS), the Helium Oxygen Proton Electron (HOPE) sensor, and the Relativistic Electron Proton Telescope (REPT). Collectively they cover, continuously, the full electron and ion spectra from one eV to 10's of MeV with sufficient energy resolution, pitch angle coverage and resolution, and with composition measurements in the critical energy range up to 50 keV and also from a few to 50 MeV/nucleon. All three instruments are based on measurement techniques proven in the radiation belts. The instruments use those proven techniques along with innovative new designs, optimized for operation in the most extreme conditions in order to provide unambiguous separation of ions and electrons and clean energy responses even in the presence of extreme penetrating background environments. The design, fabrication and operation of ECT spaceflight instrumentation in the harsh radiation belt environment ensure that particle measurements have the fidelity needed for closure in answering key mission science questions. ECT instrument details are provided in companion papers in this same issue. In this paper, we describe the science objectives of the RBSP-ECT instrument suite on the Van Allen Probe spacecraft within the context of the overall mission objectives, indicate how the characteristics of the instruments satisfy the requirements to achieve these objectives, provide information about science data collection and dissemination, and conclude with a description of some early mission results.

Spence, H. E.; Reeves, G. D.; Baker, D. N.; Blake, J. B.; Bolton, M.; Bourdarie, S.; Chan, A. A.; Claudepierre, S. G.; Clemmons, J. H.; Cravens, J. P.; Elkington, S. R.; Fennell, J. F.; Friedel, R. H. W.; Funsten, H. O.; Goldstein, J.; Green, J. C.; Guthrie, A.; Henderson, M. G.; Horne, R. B.; Hudson, M. K.; Jahn, J.-M.; Jordanova, V. K.; Kanekal, S. G.; Klatt, B. W.; Larsen, B. A.; Li, X.; MacDonald, E. A.; Mann, I. R.; Niehof, J.; O'Brien, T. P.; Onsager, T. G.; Salvaggio, D.; Skoug, R. M.; Smith, S. S.; Suther, L. L.; Thomsen, M. F.; Thorne, R. M.

2013-11-01

345

Medical implants and methods of making medical implants  

DOEpatents

A medical implant device having a substrate with an oxidized surface and a silane derivative coating covalently bonded to the oxidized surface. A bioactive agent is covalently bonded to the silane derivative coating. An implantable stent device including a stent core having an oxidized surface with a layer of silane derivative covalently bonded thereto. A spacer layer comprising polyethylene glycol (PEG) is covalently bonded to the layer of silane derivative and a protein is covalently bonded to the PEG. A method of making a medical implant device including providing a substrate having a surface, oxidizing the surface and reacting with derivitized silane to form a silane coating covalently bonded to the surface. A bioactive agent is then covalently bonded to the silane coating. In particular instances, an additional coating of bio-absorbable polymer and/or pharmaceutical agent is deposited over the bioactive agent.

Shaw, Wendy J; Yonker, Clement R; Fulton, John L; Tarasevich, Barbara J; McClain, James B; Taylor, Doug

2014-09-16

346

Multicomponent Implant Releasing Dexamethasone  

NASA Astrophysics Data System (ADS)

Several inflammatory conditions are usually treated with corticosteroids. There are various problems like side effects with traditional applications of steroids, e.g. topical, or systemic routes. Local drug delivery systems have been studied and developed to gain more efficient administration with fewer side effects. Earlier, we reported on developing Dexamethasone (DX) releasing biodegradable fibers. However, their drug release properties were not satisfactory in terms of onset of drug release. Thus, we assessed the development of multicomponent (MC) implant to enhance earlier drug release from such biodegradable fibers. Poly (lactide-co-glycolide) (PLGA) and 2 wt-% and 8 wt-% DX were compounded and extruded with twin-screw extruder to form of fibers. Some of the fibers were sterilized to obtain a change in drug release properties. Four different fiber classes were studied: 2 wt-%, 8 wt-%, sterilized 2 wt-%, and sterilized 8 wt-%. 3×4 different DX-releasing fibers were then heat-pressed to form one multicomponent rod. Half of the rods where sterilized. Drug release was measured from initial fibers and multicomponent rods using a UV/VIS spectrometer. Shear strength and changes in viscosity were also measured. Drug release studies showed that drug release commenced earlier from multicomponent rods than from component fibers. Drug release from multicomponent rods lasted from day 30 to day 70. The release period of sterilized rods extended from day 23 to day 57. When compared to the original component fibers, the drug release from MC rods commenced earlier. The initial shear strength of MC rods was 135 MPa and decreased to 105 MPa during four weeks of immersion in phosphate buffer solution. Accordingly, heat pressing has a positive effect on drug release. After four weeks in hydrolysis, no disintegration was observed.

Nikkola, L.; Vapalahti, K.; Ashammakhi, N.

2008-02-01

347

Cochlear Implantation in Older Adults  

PubMed Central

Cochlear implants allow individuals with severe-to-profound hearing loss access to sound and spoken language. The number of older adults in the United States who are potential candidates for cochlear implantation is approximately 150,000 and will continue to increase with the aging of the population. Should cochlear implantation (CI) be routinely recommended for these older adults, and do these individuals benefit from CI? We reviewed our 12 year experience with cochlear implantation in adults ?60 years (n = 445) at Johns Hopkins to investigate the impact of CI on speech understanding and to identify factors associated with speech performance. Complete data on speech outcomes at baseline and 1 year post-CI were available for 83 individuals. Our results demonstrate that cochlear implantation in adults ?60 years consistently improved speech understanding scores with a mean increase of 60. 0% (S. D. 24. 1) on HINT sentences in quiet . The magnitude of the gain in speech scores was negatively associated with age at implantation such that for every increasing year of age at CI the gain in speech scores was 1. 3 percentage points less (95% CI: 0. 6 – 1. 9) after adjusting for age at hearing loss onset. Conversely, individuals with higher pre-CI speech scores (HINT scores between 40–60%) had significantly greater post-CI speech scores by a mean of 10. 0 percentage points (95% CI: 0. 4 – 19. 6) than those with lower pre-CI speech scores (HINT <40%) after adjusting for age at CI and age at hearing loss onset. These results suggest that older adult CI candidates who are younger at implantation and with higher preoperative speech scores obtain the highest speech understanding scores after cochlear implantation with possible implications for current Medicare policy. Finally, we provide an extended discussion of the epidemiology and impact of hearing loss in older adults. Future research of CI in older adults should expand beyond simple speech outcomes to take into account the broad cognitive, social, and physical functioning outcomes that are likely detrimentally impacted by hearing loss and may be mitigated by cochlear implantation. PMID:22932787

Lin, Frank R.; Chien, Wade W.; Li, Lingsheng; Niparko, John K.; Francis, Howard W.

2012-01-01

348

Revision total hip arthroplasty: the femoral side using cemented implants  

Microsoft Academic Search

Advances in surgical technique and implant technology have improved the ten-year survival after primary total hip arthroplasty\\u000a (THA). Despite this, the number of revision procedures has been increasing in recent years, a trend which is predicted to\\u000a continue into the future. Revision THA is a technically demanding procedure often complicated by a loss of host bone stock\\u000a which may be

Graeme Holt; Samantha Hook; Matthew Hubble

2011-01-01

349

Complications at the Time of Transcatheter Aortic Valve Implantation  

PubMed Central

Transcatheter aortic valve implantation (TAVI) improves the prognosis of patients with severe aortic stenosis who are deemed too high risk for surgical valve replacement.1 However, this evolving technology is associated with a wide range of potential complications — some specific to TAVI, some often fatal. Prevention, early recognition, and effective treatment of these complications will significantly improve the outcome of this procedure and are essential prerequisites before the therapy is extended to lower-risk patient subsets. PMID:22891127

Brecker, Stephen J.D.; Roy, David; Jahangiri, Marjan

2012-01-01

350

SURFACE CHEMISTRY INFLUENCE IMPLANT BIOCOMPATIBILITY  

PubMed Central

Implantable medical devices are increasingly important in the practice of modern medicine. Unfortunately, almost all medical devices suffer to a different extent from adverse reactions, including inflammation, fibrosis, thrombosis and infection. To improve the safety and function of many types of medical implants, a major need exists for development of materials that evoked desired tissue responses. Because implant-associated protein adsorption and conformational changes thereafter have been shown to promote immune reactions, rigorous research efforts have been emphasized on the engineering of surface property (physical and chemical characteristics) to reduce protein adsorption and cell interactions and subsequently improve implant biocompatibility. This brief review is aimed to summarize the past efforts and our recent knowledge about the influence of surface functionality on protein:cell:biomaterial interactions. It is our belief that detailed understandings of bioactivity of surface functionality provide an easy, economic, and specific approach for the future rational design of implantable medical devices with desired tissue reactivity and, hopefully, wound healing capability. PMID:18393890

Thevenot, Paul; Hu, Wenjing; Tang, Liping

2011-01-01

351

PROPERTIES OF DEFECTS AND IMPLANTS IN Mg+ IMPLANTED SILICON CARBIDE  

SciTech Connect

As a candidate material for fusion reactor designs, silicon carbide (SiC) under high-energy neutron irradiation undergoes atomic displacement damage and transmutation reactions that create magnesium as one of the major metallic products. The presence of Mg and lattice disorder in SiC is expected to affect structural stability and degrade thermo-mechanical properties that could limit SiC lifetime for service. We have initiated a combined experimental and computational study that uses Mg+ ion implantation and multiscale modeling to investigate the structural and chemical effects in Mg implanted SiC and explore possible property degradation mechanisms.

Jiang, Weilin; Zhu, Zihua; Varga, Tamas; Bowden, Mark E.; Manandhar, Sandeep; Roosendaal, Timothy J.; Hu, Shenyang Y.; Henager, Charles H.; Kurtz, Richard J.; Wang, Yongqiang

2013-09-25

352

Analysis of induced electrical currents from magnetic field coupling inside implantable neurostimulator leads  

PubMed Central

Background Over the last decade, the number of neurostimulator systems implanted in patients has been rapidly growing. Nearly 50, 000 neurostimulators are implanted worldwide annually. The most common type of implantable neurostimulators is indicated for pain relief. At the same time, commercial use of other electromagnetic technologies is expanding, making electromagnetic interference (EMI) of neurostimulator function an issue of concern. Typically reported sources of neurostimulator EMI include security systems, metal detectors and wireless equipment. When near such sources, patients with implanted neurostimulators have reported adverse events such as shock, pain, and increased stimulation. In recent in vitro studies, radio frequency identification (RFID) technology has been shown to inhibit the stimulation pulse of an implantable neurostimulator system during low frequency exposure at close distances. This could potentially be due to induced electrical currents inside the implantable neurostimulator leads that are caused by magnetic field coupling from the low frequency identification system. Methods To systematically address the concerns posed by EMI, we developed a test platform to assess the interference from coupled magnetic fields on implantable neurostimulator systems. To measure interference, we recorded the output of one implantable neurostimulator, programmed for best therapy threshold settings, when in close proximity to an operating low frequency RFID emitter. The output contained electrical potentials from the neurostimulator system and those induced by EMI from the RFID emitter. We also recorded the output of the same neurostimulator system programmed for best therapy threshold settings without RFID interference. Using the Spatially Extended Nonlinear Node (SENN) model, we compared threshold factors of spinal cord fiber excitation for both recorded outputs. Results The electric current induced by low frequency RFID emitter was not significant to have a noticeable effect on electrical stimulation. Conclusions We demonstrated a method for analyzing effects of coupled magnetic field interference on implantable neurostimulator system and its electrodes which could be used by device manufacturers during the design and testing phases of the development process. PMID:22014169

2011-01-01

353

21 CFR 522.1350 - Melatonin implant.  

Code of Federal Regulations, 2013 CFR

...One implant per mink. (2) Indications for use . For use in healthy male and female kit and adult female mink (Mustela vison ) to accelerate the fur priming cycle. (3) Limitations . For subcutaneous implantation in mink only....

2013-04-01

354

21 CFR 522.1350 - Melatonin implant.  

Code of Federal Regulations, 2014 CFR

...One implant per mink. (2) Indications for use. For use in healthy male and female kit and adult female mink (Mustela vison ) to accelerate the fur priming cycle. (3) Limitations. For subcutaneous implantation in mink only....

2014-04-01

355

21 CFR 522.1350 - Melatonin implant.  

Code of Federal Regulations, 2012 CFR

...One implant per mink. (2) Indications for use . For use in healthy male and female kit and adult female mink (Mustela vison ) to accelerate the fur priming cycle. (3) Limitations . For subcutaneous implantation in mink only....

2012-04-01

356

[Dental implantation by low-density bone].  

PubMed

The paper analyzes modern approaches to bone density evaluation by planning of dental implantation procedure. Implantation technique in patients with low-density bone creating favorable conditions for osseous integration is described. PMID:23268182

Kulakov, A A; Arkhipov, A V

2012-01-01

357

Educational Challenges for Children with Cochlear Implants.  

ERIC Educational Resources Information Center

This article addresses educational challenges for children with severe to profound hearing loss who receive cochlear implants. Despite the implants, these children face acoustic challenges, academic challenges, attention challenges, associative challenges, and adjustment challenges. (Contains references.) (Author/DB)

Chute, Patricia M.; Nevins, Mary Ellen

2003-01-01

358

Implanting Beef Calves and Stocker Cattle  

E-print Network

Implanting beef calves offers one of the highest benefit-to-cost ratios of all the management practices available to cow/calf and stocker cattle producers. This publication offers advice on implant administration....

McCollum III, Ted

1998-04-24

359

21 CFR 522.1350 - Melatonin implant.  

Code of Federal Regulations, 2011 CFR

...Indications for use . For use in healthy male and female kit and adult female mink (Mustela vison ) to accelerate the fur priming cycle. (3) Limitations . For subcutaneous implantation in mink only. Do not implant potential breeding stock....

2011-04-01

360

21 CFR 522.1350 - Melatonin implant.  

Code of Federal Regulations, 2010 CFR

...Indications for use . For use in healthy male and female kit and adult female mink (Mustela vison ) to accelerate the fur priming cycle. (3) Limitations . For subcutaneous implantation in mink only. Do not implant potential breeding stock....

2010-04-01

361

Who Needs an Implantable Cardioverter Defibrillator?  

MedlinePLUS

... page from the NHLBI on Twitter. Who Needs an Implantable Cardioverter Defibrillator? Implantable cardioverter defibrillators (ICDs) are ... children, teens, and adults. Your doctor may recommend an ICD if you're at risk for certain ...

362

Defect characteristics by boron cluster ion implantation  

NASA Astrophysics Data System (ADS)

Cluster ion implantation using decaborane (B 10H 14) has been proposed as a shallow implantation technique for LSI devices with gate lengths of several-tens nanometers. Experiments and computer simulations of low-energy boron monomers and decaborane clusters implantation were performed. Molecular dynamics simulations of B 10 cluster implantation have shown similar implant depth but different damage density and damage structure compared to monomer (B 1) ion implantation with the same energy-per-atom. For monomer implantation, point-defects such as vacancy-interstitial pairs are mainly formed. On the other hand, B 10 generates large numbers of defects within a highly-amorphised region at the impact location. This difference in damage structure produced during implantation is expected to cause different annihilation processes.

Aoki, Takaaki; Matsuo, Jiro; Takaoka, Gikan; Toyoda, Noriaki; Yamada, Isao

2003-05-01

363

21 CFR 878.4300 - Implantable clip.  

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4300 Implantable clip. (a) Identification. An implantable clip is a...

2012-04-01

364

21 CFR 878.4750 - Implantable staple.  

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4750 Implantable staple. (a) Identification. An implantable staple is a...

2012-04-01

365

21 CFR 878.4750 - Implantable staple.  

Code of Federal Regulations, 2014 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4750 Implantable staple. (a) Identification. An implantable staple is a...

2014-04-01

366

21 CFR 878.4750 - Implantable staple.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4750 Implantable staple. (a) Identification. An implantable staple is a...

2011-04-01

367

21 CFR 878.4750 - Implantable staple.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4750 Implantable staple. (a) Identification. An implantable staple is a...

2010-04-01

368

21 CFR 878.4300 - Implantable clip.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4300 Implantable clip. (a) Identification. An implantable clip is a...

2010-04-01

369

21 CFR 878.4300 - Implantable clip.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4300 Implantable clip. (a) Identification. An implantable clip is a...

2011-04-01

370

21 CFR 878.4750 - Implantable staple.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4750 Implantable staple. (a) Identification. An implantable staple is a...

2013-04-01

371

21 CFR 878.4300 - Implantable clip.  

Code of Federal Regulations, 2014 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4300 Implantable clip. (a) Identification. An implantable clip is a...

2014-04-01

372

21 CFR 878.4300 - Implantable clip.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4300 Implantable clip. (a) Identification. An implantable clip is a...

2013-04-01

373

A low-power cochlear implant system  

E-print Network

Cochlear implants, or bionic ears, restore hearing to the profoundly deaf by bypassing missing inner-ear hair cells in the cochlea and electrically stimulating the auditory nerve. For miniaturized cochlear implants, including ...

Baker, Michael W. (Michael Warren), 1977-

2007-01-01

374

Physiological and molecular determinants of embryo implantation  

PubMed Central

Embryo implantation involves the intimate interaction between an implantation-competent blastocyst and a receptive uterus, which occurs in a limited time period known as the window of implantation. Emerging evidence shows that defects originating during embryo implantation induce ripple effects with adverse consequences on later gestation events, highlighting the significance of this event for pregnancy success. Although a multitude of cellular events and molecular pathways involved in embryo-uterine crosstalk during implantation have been identified through gene expression studies and genetically engineered mouse models, a comprehensive understanding of the nature of embryo implantation is still missing. This review focuses on recent progress with particular attention to physiological and molecular determinants of blastocyst activation, uterine receptivity, blastocyst attachment and uterine decidualization. A better understanding of underlying mechanisms governing embryo implantation should generate new strategies to rectify implantation failure and improve pregnancy rates in women. PMID:23290997

Zhang, Shuang; Lin, Haiyan; Kong, Shuangbo; Wang, Shumin; Wang, Hongmei; Wang, Haibin; Armant, D. Randall

2014-01-01

375

Analysis of Two Dow Corning Breast Implants Removed After 28 Years of Implantation  

Microsoft Academic Search

A pair of intact silicone gel breast implants that had been implanted for 28 years was analyzed after surgical removal in 1997 because of severe capsular contracture and heavily calcified capsules. The implants, manufactured by Dow Corning Corporation, were seamless, teardrop-shaped Cronin style (Silastic® 0) with Dacron® fixation patches. To determine the effects of long-term implantation, the material properties of

Harold J. Brandon; Walter Peters; V. Leroy Young; Kenneth L. Jerina; Clarence J. Wolf; Marla Watson Schorr

1999-01-01

376

Radial {sup 32}P ion implantation using a coaxial plasma reactor: Activity imaging and numerical integration  

SciTech Connect

Beta-emitting biomedical implants are currently employed in angioplasty, in the treatment of certain types of cancers, and in the embolization of aneurysms with platinum coils. Radioisotopes such as {sup 32}P can be implanted using plasma-based ion implantation (PBII). In this article, we describe a reactor that was developed to implant radioisotopes into cylindrical metallic objects. The plasma first ionizes radioisotopes sputtered from a target, and then acts as the source of particles to be implanted into the biased biomedical device. The plasma therefore plays a major role in the ionization/implantation process. Following a sequence of implantation tests, the liners protecting the interior walls of the reactor were changed and the radioactivity on them measured. This study demonstrates that the radioactive deposits on these protective liners, adequately imaged by radiography, can indicate the distribution of the radioisotopes that are not implanted. The resulting maps give unique information about the activity distribution, which is influenced by the sputtering of the {sup 32}P-containing fragments, their ionization in the plasma, and also by the subsequent ion transport mechanisms. Such information can be interpreted and used to significantly improve the efficiency of the implantation procedure. Using a surface barrier detector, a comparative study established a relationship between the gray scale of radiographs of the liners, and activity measurements. An integration process allows the quantification of the activities on the walls and components of the reactor. Finally, the resulting integral of the {sup 32}P activity is correlated to the sum of the radioactivity amounts that were sputtered from radioactive targets inside the implanter before the dismantling procedure. This balance addresses the issue of security regarding PBII technology and confirms the confinement of the radioactivity inside the chamber.

Fortin, M.A.; Dufresne, V.; Paynter, R.; Sarkissian, A.; Stansfield, B. [INRS-EMT, 1650 boulevard Lionel Boulet, Varennes, Quebec J3X 1S2 (Canada); Plasmionique Inc., 1650 boulevard Lionel Boulet, Varennes, Quebec J3X 1S2 (Canada); INRS-EMT, 1650 boulevard Lionel Boulet, Varennes, Quebec J3X 1S2 (Canada)

2004-12-01

377

Neurophysiologic Basis for Cochlear and Auditory Brainstem Implants  

E-print Network

Neurophysiologic Basis for Cochlear and Auditory Brainstem Implants Aage R. Møller Callier Center for cochlear and brainstem implants is discussed. It is concluded that the success of cochlear implants may: cochlear implants, brainstem implants, auditory physiology. Cochlear implants were pioneered by Michelson

O'Toole, Alice J.

378

Skewness of implanted ion profiles  

NASA Astrophysics Data System (ADS)

Skewness of implanted ion profiles is determined by extending the Biersack model to higher-order terms. Nuclear and electronic energy losses up to the fourth moment are included in the skewness equations to yield better results for any ion-target combination. The feasibility of the proposed skewness equations is examined using profiles of various ions implanted into target materials of up to two constituents. Calculated skewness values correlate well with experimental data. Kurtosis values calculated using Biersack's fitting formula also closely correspond to experimental data.

Liang, J. H.; Liao, K. Y.

379

Mutation breeding by ion implantation  

NASA Astrophysics Data System (ADS)

Ion implantation as a new mutagenic method has been used in the rice breeding program since 1986, and for mutation breeding of other crops later. It has been shown, in principle and in practice, that this method has many outstanding advantages: lower damage rate; higher mutation rate and wider mutational spectrum. Many new lines of rice with higher yield rate; broader disease resistance; shorter growing period but higher quality have been bred from ion beam induced mutants. Some of these lines have been utilized for the intersubspecies hybridization. Several new lines of cotton, wheat and other crops are now in breeding. Some biophysical effects of ion implantation for crop seeds have been studied.

Yu, Zengliang; Deng, Jianguo; He, Jianjun; Huo, Yuping; Wu, Yuejin; Wang, Xuedong; Lui, Guifu

1991-07-01

380

Radiographic evaluation of hip implants.  

PubMed

Serial radiographs are the mainstay in the longitudinal assessment of hip implants. The prosthesis, periprosthetic bone, and juxta-articular soft tissues are inspected for fracture, periosteal reaction, stress shielding, calcar resorption, osteolysis, bony remodeling, metallic debris, and heterotopic ossification. Comparison radiographs best confirm implant migration, subsidence, and aseptic loosening. Infection, particle disease, reaction to metal, and mechanical impingement are important causes of postsurgical pain, but in their earliest stages they may be difficult to diagnose using radiographs. This article addresses the role of radiography following hip arthroplasty. PMID:25633021

Chang, Connie Y; Huang, Ambrose J; Palmer, William E

2015-02-01

381

A novel ECT-EST combined method for gas-solids flow pattern and charge distribution visualization  

NASA Astrophysics Data System (ADS)

A non-invasive measurement method of visualizing the flow pattern and charge distribution of gas-solids two-phase flow has been studied and verified using gravity-dropping and pneumatic conveyance rigs with pulverized coal as solids. It has been proven that the permittivity distribution acquired from an electrical capacitance tomography (ECT) system can be used to improve the accuracy in establishing charge sensitivity field of an electrostatic tomography (EST) system, and to reduce the uncertainty of charge distribution reconstruction. The experimental results show that, under the given experimental conditions for the gravity-dropping system, charge density increases with particles' concentration, whilst in the pneumatic conveyance system, charge density decreases in the area where the particles' concentration is higher, and the total charge intensity decreases with the increase of the concentration of pulverized coal in the pipe. The method proposed in this paper is potentially important in pneumatic processes for charge distribution measurement and safe operations. It is envisaged that with further development, this technique can provide information for investigation into the mechanism of inter-particle force on electrostatic attraction and repulsion.

Zhou, B.; Zhang, J. Y.

2013-07-01

382

Corrosion and fatigue of surgical implants  

NASA Technical Reports Server (NTRS)

Implants for the treatment of femoral fractures, mechanisms leading to the failure or degradation of such structures, and current perspectives on surgical implants are discussed. Under the first heading, general usage, materials and procedures, environmental conditions, and laboratory analyses of implants after service are considered. Corrosion, crevice corrosion, stress corrosion cracking, intergranular corrosion, pitting corrosion, fatigue, and corrosion fatigue are the principal degradation mechanisms described. The need for improvement in the reliability of implants is emphasized.

Lisagor, W. B.

1975-01-01

383

Domination game: e#ect of edge and vertexremoval Bostjan Bresar a,d Paul Dorbec b Sandi Klavzar c,a,d  

E-print Network

Domination game: e#ect of edge­ and vertex­removal BoŸstjan BreŸsar a,d Paul Dorbec b Sandi Klav and Mechanics, Ljubljana, Slovenia Abstract The domination game is played on a graph G by two players, named of vertices dominated before the move on it. Dominator's goal is that the game is finished as soon as possible

Klavzar, Sandi

384

Domination game: e#ect of edge and vertexremoval Bostjan Bresar a Paul Dorbec b Sandi Klavzar c,a Gasper Kosmrlj c  

E-print Network

Domination game: e#ect of edge­ and vertex­removal BoŸstjan BreŸsar a Paul Dorbec b Sandi Klav sandi.klavzar@fmf.uni­lj.si gasper.kosmrlj@student.fmf.uni­lj.si Abstract The domination game is played is that the game is finished as soon as possible, while Staller wants the game to last as long as possible

Klavzar, Sandi

385

New advances in erectile technology  

PubMed Central

New discoveries and technological advances in medicine are rapid. The role of technology in the treatment of erectile dysfunction (ED) will be widened and more options will be available in the years to come. These erectile technologies include external penile support devices, penile vibrators, low intensity extracorporeal shockwave, tissue engineering, nanotechnology and endovascular technology. Even for matured treatment modalities for ED, such as vacuum erectile devices and penile implants, there is new scientific information and novel technology available to improve their usage and to stimulate new ideas. We anticipate that erectile technologies may revolutionize ED treatment and in the very near future ED may become a curable condition. PMID:24489605

Stein, Marshall J.; Lin, Haocheng

2014-01-01

386

Negative continuum e ects on the two{photon decay rates of hydrogen{like ions Andrey Surzhykov 1;2 , Jos e Paulo Santos 3;4 , Pedro Amaro 1;3;4 and Paul Indelicato 5  

E-print Network

- tum electrodynamical (QED) e#11;ects [14] as well as about the basic concepts of quantum physics- tems, much of today's interest is focused also on the two{photon transitions in high{Z ions and atoms

Recanati, Catherine

387

Implants and Ethnocide: Learning from the Cochlear Implant Controversy  

ERIC Educational Resources Information Center

This paper uses the fictional case of the "Babel fish" to explore and illustrate the issues involved in the controversy about the use of cochlear implants in prelinguistically deaf children. Analysis of this controversy suggests that the development of genetic tests for deafness poses a serious threat to the continued flourishing of Deaf culture.…

Sparrow, Robert

2010-01-01

388

Knee implants – Review of models and biomechanics  

Microsoft Academic Search

Since the 1950s, knee implants have been designed to replace damaged cartilage and bone of the tibiofemoral and patellofemoral joints. At least 150 implants exist today, with advancements by physicians and engineers that simulate the geometry and behavior of a healthy knee joint. Various researchers have evaluated the biomechanics of knee implant components to assess the performance of some of

Brandi C. Carr; Tarun Goswami

2009-01-01

389

(ii) Implant removal in revision hip surgery  

Microsoft Academic Search

Implant removal is a major part of revision hip surgery. A complication, such as fracture or perforation during implant removal, more common in the presence of surrounding osteopenia, can compromise subsequent reconstruction. Similarly, care must be taken to avoid additional bone loss during implant removal. Various techniques are available on both the femoral and acetabular sides that can facilitate the

Andrew R. J. Manktelow

2009-01-01

390

New Dependability Approach for Implanted Medical Devices  

E-print Network

New Dependability Approach for Implanted Medical Devices Fabien Soulier§, Fanny Le Floch§, Serge, this paper proposes a strategy for risk management at system level for FES medical implant. The idea a new strategy for risk manage- ment at system level for FES medical implant. The aim is to propose

Paris-Sud XI, Université de

391

Security and Privacy for Implantable Medical Devices  

Microsoft Academic Search

Protecting implantable medical devices against attack without compromising patient health requires balancing security and privacy goals with traditional goals such as safety and utility. Implantable medical devices monitor and treat physiological conditions within the body. These devices - including pacemakers, implantable cardiac defibrillators (ICDs), drug delivery systems, and neurostimulators - can help manage a broad range of ailments, such as

Daniel Halperin; Thomas S. Heydt-benjamin; Kevin Fu; Tadayoshi Kohno; William H. Maisel

2008-01-01

392

From neuroprosthetics to implanted FES control architecture  

Microsoft Academic Search

In this paper, we deal with complementary aspects of an implanted functional electrical stimulation control architecture: distributed stimulation units, deterministic implanted network, architecture implantation (electronic devices) and control over this network. We argue from analogy with embedded control architecture, of robots for example, from distributed control, closed-loop control, supervisory control and fieldbus considerations. The global embedded FES architecture on which

Guillaume Souquet; David Andreu; David Guiraud

2008-01-01

393

A Curvable Silicon Retinal Implant Rostam Dinyari  

E-print Network

developed a thin (30m thick) photovoltaic silicon implant that, when combined with a goggle-mounted optical Abstract We have developed a curvable photovoltaic monolithic retinal implant that requires no electrical of the retinal pigment epithelium (RPE). The implant consists of a two-dimensional (2D) array of photovoltaic

Palanker, Daniel

394

Bone response to machined cast titanium implants  

Microsoft Academic Search

The aim was to evaluate the bone response to machined cast titanium (Ti) implants. Commercially pure (c.p.) machined Ti implants served as controls. Analyses of the surface composition and topography by Auger electron spectroscopy (AES) and scanning electron microscopy (SEM) revealed no differences comparing the two materials. Cast screw-shaped and identical machined Ti implants were inserted in the tibial metaphysis

S. Mohammadi; M. Esposito; L. Wictorin; B.-O. Aronsson; P. Thomsen

2001-01-01

395

Effects of a new implant abutment design on peri-implant soft tissues.  

PubMed

The purpose of this study was to assess the effects of a modified implant abutment design on peri-implant soft and hard tissues in dogs. Three months after extraction of mandibular premolar teeth, 3 dental implants were placed in each side of the jaw using a 1-stage approach. Implants on one side of the mandible received standard abutments (control), and implants on the contralateral side received modified, patented, grooved abutments (test). Two months after implant placement, animals were euthanized and specimens were prepared for histologic and histomorphometric assessment. The linear distance (in micrometers) was measured from the implant shoulder (IS) to the following landmarks: gingival margin (GM; distance IS-GM), most apical position of the junctional epithelium (JE; distance IS-JE), and bone crest (BC; distance IS-BC). Percent of bone-to-implant contact was also measured. Histologic assessment revealed that all implants were osseointegrated and that interimplant gingival fibers between test abutments appeared to be more numerous and organized than control abutments. The IS-GM and IS-JE distances in test implants were greater than the corresponding distances in control implants (P = .024 and P = .015, respectively), whereas crestal bone loss (IS-BC) was greater for control implants than test implants (P = .037). There were no differences between control and test implants in bone-to-implant contact (P = .69), which averaged close to 50%. These results suggest that the modified groove design incorporated in standard abutments confers both soft and hard tissue benefits. PMID:23339331

Chien, Hua-Hong; Schroering, Robert L; Prasad, Hari S; Tatakis, Dimitris N

2014-10-01

396

Modification of anti-bacterial surface properties of textile polymers by vacuum arc ion source implantation  

NASA Astrophysics Data System (ADS)

Ion implantation provides an important technology for the modification of material surface properties. The vacuum arc ion source is a unique instrument for the generation of intense beams of metal ions as well as gaseous ions, including mixed metal-gas beams with controllable metal:gas ion ratio. Here we describe our exploratory work on the application of vacuum arc ion source-generated ion beams for ion implantation into polymer textile materials for modification of their biological cell compatibility surface properties. We have investigated two specific aspects of cell compatibility: (i) enhancement of the antibacterial characteristics (we chose to use Staphylococcus aureus bacteria) of ion implanted polymer textile fabric, and (ii) the "inverse" concern of enhancement of neural cell growth rate (we chose Rat B-35 neuroblastoma cells) on ion implanted polymer textile. The results of both investigations were positive, with implantation-generated antibacterial efficiency factor up to about 90%, fully comparable to alternative conventional (non-implantation) approaches and with some potentially important advantages over the conventional approach; and with enhancement of neural cell growth rate of up to a factor of 3.5 when grown on suitably implanted polymer textile material.

Nikolaev, A. G.; Yushkov, G. Yu.; Oks, E. M.; Oztarhan, A.; Akpek, A.; Hames-Kocabas, E.; Urkac, E. S.; Brown, I. G.

2014-08-01

397

New advanced surface modification technique: titanium oxide ceramic surface implants: long-term clinical results  

NASA Astrophysics Data System (ADS)

The purpose of this paper is to discuss the background to advanced surface modification technologies and to present a new technique, involving the formation of a titanium oxide ceramic coating, with relatively long-term results of its clinical utilization. Three general techniques are used to modify surfaces: the addition or removal of material and the change of material already present. Surface properties can also be changed without the addition or removal of material, through the laser or electron beam thermal treatment. The new technique outlined in this paper relates to the production of a corrosion-resistant 2000-2500 A thick, ceramic oxide layer with a coherent crystalline structure on the surface of titanium implants. The layer is grown electrochemically from the bulk of the metal and is modified by heat treatment. Such oxide ceramic-coated implants have a number of advantageous properties relative to implants covered with various other coatings: a higher external hardness, a greater force of adherence between the titanium and the oxide ceramic coating, a virtually perfect insulation between the organism and the metal (no possibility of metal allergy), etc. The coated implants were subjected to various physical, chemical, electronmicroscopic, etc. tests for a qualitative characterization. Finally, these implants (plates, screws for maxillofacial osteosynthesis and dental root implants) were applied in surgical practice for a period of 10 years. Tests and the experience acquired demonstrated the good properties of the titanium oxide ceramic-coated implants.

Szabo, Gyorgy; Kovacs, Lajos; Barabas, Jozsef; Nemeth, Zsolt; Maironna, Carlo

2001-11-01

398

Direct metal laser sintering titanium dental implants: a review of the current literature.  

PubMed

Statement of Problem. Direct metal laser sintering (DMLS) is a technology that allows fabrication of complex-shaped objects from powder-based materials, according to a three-dimensional (3D) computer model. With DMLS, it is possible to fabricate titanium dental implants with an inherently porous surface, a key property required of implantation devices. Objective. The aim of this review was to evaluate the evidence for the reliability of DMLS titanium dental implants and their clinical and histologic/histomorphometric outcomes, as well as their mechanical properties. Materials and Methods. Electronic database searches were performed. Inclusion criteria were clinical and radiographic studies, histologic/histomorphometric studies in humans and animals, mechanical evaluations, and in vitro cell culture studies on DMLS titanium implants. Meta-analysis could be performed only for randomized controlled trials (RCTs); to evaluate the methodological quality of observational human studies, the Newcastle-Ottawa scale (NOS) was used. Results. Twenty-seven studies were included in this review. No RCTs were found, and meta-analysis could not be performed. The outcomes of observational human studies were assessed using the NOS: these studies showed medium methodological quality. Conclusions. Several studies have demonstrated the potential for the use of DMLS titanium implants. However, further studies that demonstrate the benefits of DMLS implants over conventional implants are needed. PMID:25525434

Mangano, F; Chambrone, L; van Noort, R; Miller, C; Hatton, P; Mangano, C

2014-01-01

399

The prospects for low energy implantation with large molecular ions—the case of decaborane  

NASA Astrophysics Data System (ADS)

Future generations of Si technology will need junctions shallower than 50 nm. Implantation of B to form p-type junctions of such low depth requires very low energies, below 1 keV, where beam formation and transport of ions at reasonably high currents become critical problems. This paper discusses a new approach using beams of ionized large molecules, which are implanted at the depth corresponding to a fraction of the beam energy, partitioned between the atoms of the molecule. Recently, great interest has been aroused by the reports of shallow junctions formed by implantation of decaborane (B10H14). The results are reviewed and the prospects for using these molecules in ion implanters are examined, based on measurements of their ionization properties. Recent data on comparison of transient enhanced diffusion (TED) in Si implanted with 5 keV B10H14 and with B ions of the equivalent energy and dose, are discussed. While the diffusion enhancement appears to be the same in the two cases, it is expected to diminish with further lowering of effective implantation energy, thus making molecular ion beams an attractive alternative to ultra-low energy atomic B implantation. The success of the method in industry will depend on the availability of effective sources of these ions.

Sosnowski, Marek

1999-06-01

400

Ex vivo alendronate localization at the mesoporous titania implant/bone interface.  

PubMed

An attractive approach in implant technology is local drug delivery, and design of efficient, safe and reliable treatments. Our hitherto strategy has been to coat Ti implants with a thin mesoporous TiO2 film that in turn is loaded with an osteoporosis drug, such as Alendronate (ALN) that is known to suppress osteoclastic activity. This system has proven highly successful and results in excellent osseointegration. However, more detailed information about drug-release and distribution at the bone/implant interface is needed. In this study, (14)C-ALN loaded titanium implants were placed up to 8 weeks into rat tibia and the spatial-temporal distribution of the drug was evaluated. Autoradiography data demonstrated a sustained release of (14)C-ALN and the released drug remained bound to bone in close vicinity, within 500 micrometers, of the implants. Liquid scintillation counting experiments confirmed that the distal transport of released (14)C-ALN was extremely low. The results are favorable as they show that ALN stays for a long time in the vicinity of the implant and may therefore improve for a long time the mechanical fixation of bone anchored implants. Moreover, these findings suggest due to the low systemic spreading a minimal risk of Alendronate related systemic side effects. PMID:25577217

Karlsson, Johan; Harmankaya, Necati; Allard, Stefan; Palmquist, Anders; Halvarsson, Mats; Tengvall, Pentti; Andersson, Martin

2015-01-01

401

Phase formation and corrosion behavior of nitrogen implanted Zr Sn Nb alloy in alkaline environment  

NASA Astrophysics Data System (ADS)

Fretting induced corrosion occurring at the tube-grid contact is a very important problem for cladding materials and ion implantation has been considered an effective technology capable of improving the corrosion resistance of fuel cladding material without noticeably changing in dimensional integrity. In this paper, Zr-Sn-Nb specimens were implanted by nitrogen with fluence range from 5 × 10 16 to 4 × 10 17 ions/cm 2, and then subjected to electrochemical study in a solution with pH = 10 in order to determine the optimum fluence that can give good corrosion resistance in a simulated nuclear reactor condition. Glancing angle X-ray diffraction (GAXRD) was employed on the implanted to understand phase formation with increasing fluences. The depth profile of the oxides in the scale was analyzed by Auger electron spectroscopy (AES). The results showed the corrosion resistance of Zr-Sn-Nb was sensitive to the ion fluence and the substrate temperature during the implantation. The alloy implanted at below 473 K exhibited an inferior corrosion resistance to the unimplanted sample irrespective of the ion fluence. A drastic increase in the resistance to pitting corrosion in alkaline solution of the implanted alloy, were found to be associated with the formation of ZrN layer with a stoichiometric ratio of N to Zr. The worse corrosion resistance of the alloy implanted at below 473 K may be attributed to the increase in structural defects produced by ion bombardment.

Liu, Y. Z.; Zu, X. T.; Zhu, S.; Wang, L. M.

2006-05-01

402

Direct Metal Laser Sintering Titanium Dental Implants: A Review of the Current Literature  

PubMed Central

Statement of Problem. Direct metal laser sintering (DMLS) is a technology that allows fabrication of complex-shaped objects from powder-based materials, according to a three-dimensional (3D) computer model. With DMLS, it is possible to fabricate titanium dental implants with an inherently porous surface, a key property required of implantation devices. Objective. The aim of this review was to evaluate the evidence for the reliability of DMLS titanium dental implants and their clinical and histologic/histomorphometric outcomes, as well as their mechanical properties. Materials and Methods. Electronic database searches were performed. Inclusion criteria were clinical and radiographic studies, histologic/histomorphometric studies in humans and animals, mechanical evaluations, and in vitro cell culture studies on DMLS titanium implants. Meta-analysis could be performed only for randomized controlled trials (RCTs); to evaluate the methodological quality of observational human studies, the Newcastle-Ottawa scale (NOS) was used. Results. Twenty-seven studies were included in this review. No RCTs were found, and meta-analysis could not be performed. The outcomes of observational human studies were assessed using the NOS: these studies showed medium methodological quality. Conclusions. Several studies have demonstrated the potential for the use of DMLS titanium implants. However, further studies that demonstrate the benefits of DMLS implants over conventional implants are needed. PMID:25525434

Mangano, F.; Chambrone, L.; van Noort, R.; Miller, C.; Hatton, P.; Mangano, C.

2014-01-01

403

Optical waveguides in TiO? formed by He ion implantation.  

PubMed

We report on the formation and the optical properties of the planar and ridge optical waveguides in rutile TiO? crystal by He+ ion implantation combined with micro-fabrication technologies. Planar optical waveguides in TiO? are fabricated by high-energy (2.8 MeV) He+-ion implantation with a dose of 3 × 10¹? ions/cm² and triple low energies (450, 500, 550) keV He+-ion implantation with all fluences of 2 × 10¹? ions/cm² at room temperature. The guided modes were measured by a modal 2010 prism coupler at wavelength of 1539 nm. There are damage profiles in ion-implanted waveguides by Rutherford backscattering (RBS)/channeling measurements. The refractive-index profile of the 2.8 MeV He+-implanted waveguide was analyzed based on RCM (Reflected Calculation Method). Also ridge waveguides were fabricated by femtosecond laser ablation on 2.8 MeV ion implanted planar waveguide and Ar ion beam etching on the basis of triple keV ion implanted planar waveguide, separately. The loss of the ridge waveguide was estimated. The measured near-field intensity distributions of the planar and ridge modes are all shown. PMID:22418555

Bi, Zhuan-Fang; Wang, Lei; Liu, Xiu-Hong; Zhang, Shao-Mei; Dong, Ming-Ming; Zhao, Quan-Zhong; Wu, Xiang-Long; Wang, Ke-Ming

2012-03-12

404

Biocompatible coatings on titanium implants  

Microsoft Academic Search

Titanium metal and alloys are widely used as materials implanted. Due to the natural film of titanium oxide on titanium surface it stands against corrosion and is considered to be bioinert material. Cohesive resistance of this film as well as its strength is not high. Titanium and alloys are put on oxidation for the purpose to obtain the film with

V. P. Ignatov; T. S. Petrovskaya

2003-01-01

405

Cortical Plasticity after Cochlear Implantation  

PubMed Central

The most dramatic progress in the restoration of hearing takes place in the first months after cochlear implantation. To map the brain activity underlying this process, we used positron emission tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners with prelingual hearing loss. Furthermore, Broca's area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca's area in restoration of speech perception, but only in individuals in whom Broca's area has been active prior to the loss of hearing. PMID:24377050

Petersen, B.; Gjedde, A.; Wallentin, M.; Vuust, P.

2013-01-01

406

Will Retinal Implants Restore Vision?  

Microsoft Academic Search

A number of research groups are developing electrical implants that can be attached directly to the retina in an attempt to restore vision to patients suffering from retinal degeneration. However, despite promising results in animal experiments, there are still several major obstacles to overcome before retinal prostheses can be used clinically.

Eberhart Zrenner

2002-01-01

407

Partially implantable vibrating ossicular prosthesis  

Microsoft Academic Search

A partially implantable hearing prosthesis for sensorineural hearing loss patients has been developed using a novel electromagnetic actuator. The system is designed to couple acoustic frequency, vibrational energy into the ossicular structure of the middle ear. The complete system includes external signal processing and a transdermal telemetry system. The focus of this paper is to describe the transducer used to

Timothy G. Dietz; Geoffrey R. Ball; Bob H. Katz

1997-01-01

408

Cortical plasticity after cochlear implantation.  

PubMed

The most dramatic progress in the restoration of hearing takes place in the first months after cochlear implantation. To map the brain activity underlying this process, we used positron emission tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners with prelingual hearing loss. Furthermore, Broca's area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca's area in restoration of speech perception, but only in individuals in whom Broca's area has been active prior to the loss of hearing. PMID:24377050

Petersen, B; Gjedde, A; Wallentin, M; Vuust, P

2013-01-01

409

Contamination Control in Ion Implantation  

SciTech Connect

The investigation and elimination or control of metallic contamination in ion implanters has been a leading, continuous effort at implanter OEMs and in fabs/IDMs alike. Much of the efforts have been in the area of control of sputtering through material and geometry changes in apertures, beamline and target chamber components. In this paper, we will focus on an area that has not, heretofore, been fully investigated or controlled. This is the area of lubricants and internal and external support material such as selected cleaning media. Some of these materials are designated for internal use (beamline/vacuum) only while others are for internal and/or external use. Many applications for selected greases, for example, are designated for or are used for platens, implant disks/wheels and for wafer handling components. We will present data from popular lubricants (to be unnamed) used worldwide in ion implanters. This paper will review elements of concern in many lubricants that should be tracked and monitored by all fabs.Proper understanding of the characteristics, risks and the control of these potential contaminants can provide for rapid return to full process capability following major PMs or parts changes. Using VPD-ICPMS, Glow Discharge Mass Spectrometry and Ion Chromatography (IC) data, we will review the typical cleaning results and correlation to ''on wafer'' contamination by elements of concern--and by some elements that are otherwise barred from the fab.

Eddy, R. [KLE Engineering, 365 High Chaparral Loop, Prescott AZ 86303 (United States); Doi, D. [Fastgate Corporation, 1011 Niizo, Toda, Saitama 335-001 (Japan); Santos, I.; Wriggins, W. [Core Systems, 1050 Kifer Rd. Sunnyvale, CA 94086 (United States)

2011-01-07

410

He reemission implanted in metals  

NASA Astrophysics Data System (ADS)

Helium (He) reemission of Al, Ni and Mo under energetic He implantation (10-30 keV) in wide temperature range is studied to understand behavior of implanted He in correlation with structure changes. The reemission behavior is categorized into 4 different temperature ranges with the normalized temperature (Tm) to the melting point of each metal. At elevated temperatures (well above ?0.6 Tm), interstitial He atoms and/or He-vacancy (ies) clusters can migrate remaining no structure change and showing smooth reemission without any burst. Between ?0.25 and 0.6 Tm, He reemission always accompanies significant structure modification. For ?04-0.6 Tm, implanted He coalesce to make bubbles and the bubbles can move to the surface. Bubble migration accompanies materials flow to the surface resulting in fuzz surface or columnar structure, depending on implantation flux. Slower bubble motion at ?0.25-0.4 prohibits the material migration. Instead the bubbles coalesce to grow large and multi-layered blistering appears as periodic reemission behavior. Below ?0.25 Tm, He migration is too slow for bubbles to grow large, but bubble density increases up to a certain fluence, where neighboring bubbles start to coalesce. Accordingly, He release is mostly caused by mechanical failure or blister rapture. With increasing fluence, all defects (bubbles and dislocation loops) tangle or inter connected with neighboring defects and accordingly He migration to the surface along the tangled or connected defects is enhanced, resulting 100% reemission easily without making multilayered blistering.

Tanabe, T.

2014-10-01

411

Dental implant changes following incineration  

Microsoft Academic Search

Non-visual identification of victims utilizes DNA, fingerprint and dental comparison as primary scientific identifiers. In incidents where a victim has been incinerated, there may be loss of fingerprint detail and denaturing of DNA. Although extremely durable, tooth loss will also occur with extreme temperatures and the characteristics of recovered dental implants, if any, may be the only physical identifying data

J. Berketa; H. James; V. Marino

2011-01-01

412

Vestibular Effects of Cochlear Implantation  

Microsoft Academic Search

Objectives\\/Hypothesis: Cochlear implantation (CI) carries with it the potential risk for vestibular system insult or stimulation with resultant dysfunc- tion. As candidate profiles continue to evolve and with the recent development of bilateral CI, under- standing the significance of this risk takes on an in- creasing importance. Study Design: Between 1997 to 2001, a prospective observational study was carried out

Craig A. Buchman; Jennifer Joy; Annelle Hodges; Fred F. Telischi; Thomas J. Balkany

2004-01-01

413

Oxygen Ion Implantation into Indium Phosphate  

NASA Astrophysics Data System (ADS)

This paper is the results of oxygen ion implantation on morphological and electrical properties of indium phosphate (InP) semiconductor wafers. The oxygen ions were implanted at 30 keV and various doses in the range between 5 × 1015 and 5 × 1017 ions/cm2 and at nearly room temperature. The changes in surface roughness and resistivity before and after the implantation is studied using atomic force microscopy (AFM) and four-point probes technique, respectively. The results show that the resistivity is depend on the ion implantation dose. In addition, the RMS roughness of implanted samples dramatically increases by accumulation of oxygen ion dose.

Ramezani, A. H.; Hantezadeh, M. R.; Ghoranneviss, M.; Sari, A. H.

2011-08-01

414

Hydroxyapatite-coated tooth implants by laser  

NASA Astrophysics Data System (ADS)

Thin films of biocompatible ceramic were fabricated by pulsed laser deposition on cylindrical implants. Diamond- like carbon films were deposited in vacuum on titanium alloy prostheses, heated to 90 degrees C. Coated prostheses were implanted into legs of rats and osseointegration higher than 60 percent was determined. Thin films of hydroxyapatite were created on real dental implants at 500 degrees C in Ar-water vapor atmosphere. Coated implants were implanted into mandibula of minipigs to study load free osseointegration. Results and experiences are presented and discussed.

Jelinek, Miroslav; Dostalova, Tatjana; Himmlova, Lucia; Grivas, Christos

1996-09-01

415

Peri-implant esthetics assessment and management  

PubMed Central

Providing an esthetic restoration in the anterior region of the mouth has been the basis of peri-implant esthetics. To achieve optimal esthetics, in implant supported restorations, various patient and tooth related factors have to be taken into consideration. Peri-implant plastic surgery has been adopted to improve the soft tissue and hard tissue profiles, during and after implant placement. The various factors and the procedures related to enhancement of peri-implant esthetics have been discussed in this review article. PMID:23878557

Balasubramaniam, Aarthi S.; Raja, Sunitha V.; Thomas, Libby John

2013-01-01

416

Nanoporous inorganic membranes or coatings for sustained drug delivery in implantable devices.  

PubMed

The characteristics of nanoporous inorganic coatings on implants or on implantable devices are reviewed. The commonly used nanoporous materials, such as aluminum oxide (Al(2)O(3)), titanium oxide (TiO(2)) and porous silicon are highlighted with illustrative examples. The critical issues for sustained release systems are examined and the elution profiles of nanoporous coatings are discussed. The available data shows that these systems can be used effectively for sustained release applications. They satisfy the basic biocompatibility tests, meet the requirements of drug loading and sustained release profiles extending to several weeks and also are compatible with current implant technologies. Nanoporous inorganic coatings are well suited to provide improved efficacy and integration of implants in a variety of therapeutic situations. PMID:19922749

Gultepe, Evin; Nagesha, Dattatri; Sridhar, Srinivas; Amiji, Mansoor

2010-03-01

417

Formation of ultrathin nitrided SiO{sub 2} oxides by direct nitrogen implantation into silicon  

SciTech Connect

A nitridation technique is proposed for ultrathin, SiO{sub 2} oxides in deep submicron CMOS technology, which involves direct implantation of molecular nitrogen (N{sub 2}) into the silicon substrate. N{sub 2} ions were implanted into silicon at different doses and energies, through a 150 {angstrom} thick screen oxide. In this study the effect of implanted N atoms on silicon oxidation, and SiO{sub 2} oxide nitridation process have been studied. Two groups of the N{sub 2}-implanted wafers were used: wafers from one group were annealed prior to the screen oxide removal, whereas wafers of the other group did not receive this anneal. It is shown that nitridation can be achieved both ways, allowing this technique to be easily integrated into a semiconductor IC fabrication process.

Soleimani, H.R.; Doyle, B.S.; Philipossian, A. [Digital Equipment Corp., Hudson, MA (United States). ULSI Operations Group

1995-08-01

418

Surface modification of implants in long bone.  

PubMed

Coatings of orthopedic implants are investigated to improve the osteoinductive and osteoconductive properties of the implant surfaces and thus to enhance periimplant bone formation. By applying coatings that mimic the extracellular matrix a favorable environment for osteoblasts, osteoclasts and their progenitor cells is provided to promote early and strong fixation of implants. It is known that the early bone ongrowth increases primary implant fixation and reduces the risk of implant failure. This review presents an overview of coating titanium and hydroxyapatite implants with components of the extracellular matrix like collagen type I, chondroitin sulfate and RGD peptide in different small and large animal models. The influence of these components on cells, the inflammation process, new bone formation and bone/implant contact is summarized. PMID:23507866

Förster, Yvonne; Rentsch, Claudia; Schneiders, Wolfgang; Bernhardt, Ricardo; Simon, Jan C; Worch, Hartmut; Rammelt, Stefan

2012-01-01

419

Decontamination of dental implant surface in peri-implantitis treatment: A literature review  

PubMed Central

Etiological treatment of peri-implantitis aims to reduce the bacterial load within the peri-implant pocket and decontaminate the implant surface in order to promote osseointegration. The aim of this literature review was to evaluate the efficacy of different methods of implant surface decontamination. A search was conducted using the PubMed (Medline) database, which identified 36 articles including in vivo and in vitro studies, and reviews of different decontamination systems (chemical, mechanical, laser and photodynamic therapies). There is sufficient consensus that, for the treatment of peri-implant infections, the mechanical removal of biofilm from the implant surface should be supplemented by chemical decontamination with surgical access. However, more long-term research is needed to confirm this and to establish treatment protocols responding to different implant characterics. Key words:Peri-implantitis, treatment, decontamination, implant surface, laser. PMID:23986023

Buitrago-Vera, Pedro; Solá-Ruiz, María F.; Ferrer-García, Juan C.

2013-01-01

420

Successful Rehabilitation of Partial Edentulous Maxilla and Mandible with New Type of Implants: Molecular Precision Implants  

PubMed Central

The extraction of teeth results in rapid bone resorption both vertically and horizontally in the first month. The loss of alveolar ridge reduces the chance of implant rehabilitation. Atraumatic extraction, implant placement in extraction socket, and an immediate prosthesis have been proposed as alternative therapies to maintain the volume and contours tissue and reduce time and cost of treatment. The immediate load of implants is a universally practiced procedure; nevertheless a successful procedure requires expertise in both the clinical and the reconstructive stages using a solid implant system. Excellent primary stability and high bone-implant contact are only minimal requirements for any type of implant procedure. In this paper we present a case report using a new type of implants. The new type of implants, due to its sophisticated control system of production, provides to the implantologist a safe and reliable implant, with a macromorphology designed to ensure a close contact with the surrounding bone. PMID:25525437

Danza, Matteo; Carinci, Francesco

2014-01-01

421

Effect of Platelet-Rich-Plasma (PRP) and Implant Surface Topography on Implant Stability and Bone  

PubMed Central

Purpose: To evaluate the effect of Platelet-Rich-Plasma (PRP) and different implant surface topography on implant stability and bone levels around immediately loaded dental implants. Materials and Methods: Dental implants were placed in subjects divided into two groups and four subgroups on basis of implant treatment with PRP and implant surface topography used. A total of 30 implants were placed, 15 in each group. For PRP group, implants were placed after surface treatment with PRP. Temporization was done within two weeks and final prosthesis was given after three months. Implant stability was measured with Periotest at baseline, one month and three months. Bone height was measured on mesial & distal side on standardized IOPA x-rays. Results: A statistically significant difference was noticed in implant stability with PRP at baseline. The effect of PRP on bone height changes was not statistically significant. A synergistic effect of PRP and square thread-form was observed on improved implant stability and bone levels; however, no such effect is seen with PRP and reverse buttress thread-form. Conclusion: Within the limitation of this study, enhancement on implant stability and bone healing was observed with PRP treated implant surfaces, and with use of implant with square thread-form. PMID:25121060

Kundu, Renu

2014-01-01

422

Development of batteries for implantable applications  

NASA Astrophysics Data System (ADS)

Neuroprosthetic devices that electrically stimulate paralyzed muscles require implantable power sources with exceptional cycle life, safety, and sufficient energy and power density. Of the rechargeable battery technologies, lithium ion batteries have the highest energy density; however, they have limited cycle life of about 1000 cycles. Nickel-hydrogen batteries, currently used in space applications are remarkable for long cycle life (40,000) and low maintenance; however they utilize high hydrogen pressures (60 atm) making them unsuitable for implantable applications. The present work involves design and development of low pressure nickel-hydrogen batteries (1 atm) by utilizing a metal hydride (MH) to store hydrogen, rather than as a negative electrode in the nickel-metal hydride battery. A method to increase the exchange current density of the negative platinum electrode using cyclic voltammetry was developed. A nickel mesh was chosen as the current collector because of its low resistance and stability in alkaline solutions. The tested separators, zirconium oxide and polypropylene, were not significantly different from each other. A pasted type nickel hydroxide electrode was fabricated by two means: screen printing and spatula pressing. The mechanism of electrode formation, the effect of different formation rates with and without overcharge and the effect of binder and nickel content on utilization were studied. Addition of filamentary nickel to the electrode increases the utilization by 10% by decreasing the oxygen evolution. A low pressure nickel-hydrogen battery with and without MH was assembled. Charge and pressure data were analyzed to study the oxygen evolution, the recombination reaction and the self discharge of the cell. Oxygen evolution increases with the depth of charge; however the evolved oxygen recombines completely---70% during charging and the remainder during the first hour of the rest period. About 40-45% hydrogen from the metal hydride was used as fuel during cycling. The pressure composition isotherm was used to estimate the state of charge and to fuel gauge the cell. The NM is deactivated when exposed to KOH solution, increasing the hydrogen equilibration time. Of the tested implantable lithium ion cells, Quallion outperformed the Wilson Greatbatch cells in cycle life. The conditions for maximum cycle life were determined.

Purushothaman, Bushan Kumar

423

Experimental and theoretical studies of implant assisted magnetic drug targeting  

NASA Astrophysics Data System (ADS)

One way to achieve drug targeting in the body is to incorporate magnetic nanoparticles into drug carriers and then retain them at the site using an externally applied magnetic field. This process is referred to as magnetic drug targeting (MDT). However, the main limitation of MDT is that an externally applied magnetic field alone may not be able to retain a sufficient number of magnetic drug carrier particles (MDCPs) to justify its use. Such a limitation might not exist when high gradient magnetic separation (HGMS) principles are applied to assist MDT by means of ferromagnetic implants. It was hypothesized that an Implant Assisted -- MDT (IA-MDT) system would increase the retention of the MDCPs at a target site where an implant had been previously located, since the magnetic forces are produced internally. With this in mind, the overall objective of this work was to demonstrate the feasibility of an IA-MDT system through mathematical modeling and in vitro experimentation. The mathematical models were developed and used to demonstrate the behavior and limitations of IA-MDT, and the in vitro experiments were designed and used to validate the models and to further elucidate the important parameters that affect the performance of the system. IA-MDT was studied with three plausible implants, ferromagnetic stents, seed particles, and wires. All implants were studied theoretically and experimentally using flow through systems with polymer particles containing magnetite nanoparticles as MDCPs. In the stent studies, a wire coil or mesh was simply placed in a flow field and the capture of the MDCPs was studied. In the other cases, a porous polymer matrix was used as a surrogate capillary tissue scaffold to study the capture of the MDCPs using wires or particle seeds as the implant, with the seeds either fixed within the polymer matrix or captured prior to capturing the MDCPs. An in vitro heart tissue perfusion model was also used to study the use of stents. In general, all the results demonstrated that IA-MDT is indeed feasible and that careful modification of the MDCP properties and implant properties are fundamental to the success of this technology.

Aviles, Misael O.

424

A woman's experience: living with an implantable cardioverter defibrillator.  

PubMed

The implantable cardioverter defibrillators (ICD) have decreased mortality rates from those who are at risk for sudden cardiac death or who have survived sudden cardiac death and has been shown to be superior to anti-arrhythmic medications (Greenburg et al., 2004). This advance in technology may improve physical health but can impose some challenges to patients, such as depression, anxiety, fear, and unpredictability. Published research on how ICD affects a woman's life experience using phenomenology is limited. Therefore, the purpose of this article is to describe the experiences of women who have an ICD using Colaizzi's method of phenomenology since their implant. Analysis of the three interviews resulted in five themes that described the essence of this experience. The results of this study could not only help clinicians understand what their patients are experiencing but also it can be used as an education tool. PMID:25481839

Conelius, Jaclyn

2014-11-13

425

The Responsivity of a Miniaturized Passive Implantable Wireless Pressure Sensor.  

PubMed

A miniature batteryless implantable wireless pressure sensor that can be used deep inside the body is desired by the medical community. MEMS technology makes it possible to achieve high responsivity that directly determines the operating distance between a miniature implanted sensor and the external RF probe, while providing the read-out. In this paper, for the first time, an analytical expression of the system responsivity versus the sensor design is derived using an equivalent circuit model. Also, the integration of micro-coil inductors and pressure sensitive capacitors on a single silicon chip using MEMS fabrication techniques is demonstrated. Further, the derived analytical design theory is validated by the measured responsivity of these sensors. PMID:25309965

Jiang, Hao; Lan, Di; Goldman, Ken; Etemadi, Mozziyar; Shahnasser, Hamid; Roy, Shuvo

2011-01-01

426

The Responsivity of a Miniaturized Passive Implantable Wireless Pressure Sensor  

PubMed Central

A miniature batteryless implantable wireless pressure sensor that can be used deep inside the body is desired by the medical community. MEMS technology makes it possible to achieve high responsivity that directly determines the operating distance between a miniature implanted sensor and the external RF probe, while providing the read-out. In this paper, for the first time, an analytical expression of the system responsivity versus the sensor design is derived using an equivalent circuit model. Also, the integration of micro-coil inductors and pressure sensitive capacitors on a single silicon chip using MEMS fabrication techniques is demonstrated. Further, the derived analytical design theory is validated by the measured responsivity of these sensors. PMID:25309965

Jiang, Hao; Lan, Di; Goldman, Ken; Etemadi, Mozziyar; Shahnasser, Hamid; Roy, Shuvo

2011-01-01

427

Terrestrial applications from space technology  

NASA Technical Reports Server (NTRS)

NASA's Technology Utilization Program, which is concerned with transferring aerospace technologies to the public and private sectors, is described. The strategy for transferring the NASA technologies to engineering projects includes: (1) identification of the problem, (2) selection of an appropriate aerospace technology, (3) development of a partnership with the company, (4) implementation of the project, and (5) commercialization of the product. Three examples revealing the application of aerospace technologies to projects in biomedical engineering, materials, and automation and robotics are presented; the development of a programmable, implantable medication system and a programmable, mask-based optical correlator, and the improvement of heat and erosion resistance in continuous casting are examined.

Clarks, H.

1985-01-01

428

Wearable and implantable sensors: the patient's perspective.  

PubMed

There has been a rising interest in wearable and implantable biomedical sensors over the last decade. However, many technologies have not been integrated into clinical care, due to a limited understanding of user-centered design issues. Little information is available about these issues and there is a need to adopt more rigorous evidence standards for design features to allow important medical sensors to progress quicker into clinical care. Current trends in patient preferences need to be incorporated at an early stage into the design process of prospective clinical sensors. The first comprehensive patient data set, discussing mobile biomedical sensor technology, is presented in this paper. The study population mainly consisted of individuals suffering from arthritis. It was found that sensor systems needed to be small, discreet, unobtrusive and preferably incorporated into everyday objects. The upper extremity was seen as the favored position on the body for placement, while invasive placement yielded high levels of acceptance. Under these conditions most users were willing to wear the body-worn sensor for more than 20 h a day. This study is a first step to generate research based user-orientated design criteria's for biomedical sensors. PMID:23443394

Bergmann, Jeroen H M; Chandaria, Vikesh; McGregor, Alison

2012-01-01

429

Implant periapical lesion: Diagnosis and treatment  

PubMed Central

The implant periapical lesion is the infectious-inflammatory process of the tissues surrounding the implant apex. It may be caused by different factors: contamination of the implant surface, overheating of bone during drilling, preparation of a longer implant bed than the implant itself, and pre-existing bone disease. Diagnosis is achieved by studying the presence of symptoms and signs such us pain, swelling, suppuration or fistula; in the radiograph an implant periapical radiolucency may appear. A diagnostic classification is proposed to establish the stage of the lesion, and determine the best treatment option accordingly. The following stages are distinguished: acute apical periimplantitis (non-suppurated and suppurated) and subcacute (or suppurated-fistulized) apical periimplantitis. The most adequate treatment of this pathology in the acute stage and in the subacute stage if there is no loss of implant stability is apical surgery. In the subacute stage, if there is implant mobility, the extraction of the implant is necessary. Key words:Implant periapical lesion, apical periimplantitis, retrograde periimplantitis. PMID:22926472

Maestre-Ferrín, Laura; Cervera-Ballester, Juan; Peñarrocha-Oltra, David

2012-01-01

430

Miniscrew implant applications in contemporary orthodontics.  

PubMed

The need for orthodontic treatment modalities that provide maximal anchorage control but with minimal patient compliance requirements has led to the development of implant-assisted orthodontics and dentofacial orthopedics. Skeletal anchorage with miniscrew implants has no patient compliance requirements and has been widely incorporated in orthodontic practice. Miniscrew implants are now routinely used as anchorage devices in orthodontic treatment. This review summarizes recent data regarding the interpretation of bone data (i.e., bone quantity and quality) obtained by preoperative diagnostic computed tomography (CT) or by cone-beam computed tomography (CBCT) prior to miniscrew implant placement. Such data are essential when selecting appropriate sites for miniscrew implant placement. Bone characteristics that are indications and contraindications for treatment with miniscrew implants are discussed. Additionally, bicortical orthodontic skeletal anchorage, risks associated with miniscrew implant failure, and miniscrew implants for nonsurgical correction of occlusal cant or vertical excess are reviewed. Finally, implant stability is compared between titanium alloy and stainless steel miniscrew implants. PMID:24581210

Chang, Hong-Po; Tseng, Yu-Chuan

2014-03-01

431

Ablation Plasma Ion Implantation (APII)  

NASA Astrophysics Data System (ADS)

Ablation plasmas are generated by an excimer laser incident on pure metal targets. Initial APII film depositions have implanted Fe into Si wafer substrates at negative voltages up to 10 kV. Thin film properties (e.g., adhesion, morphology) of thin films deposited by laser ablative deposition (zero voltage) will be compared to films deposited with APII. A simple one dimensional theory is developed [1] to calculate the implanted ion current, extracted from the ion matrix sheath, as a function of time for various substrate-plume separations. This model accurately recovers Lieberman's classic results when the plume front is initially in contact with the substrate. [1] B. Qi, Y. Y. Lau, and R. M. Gilgenbach, Appl. Phys. Lett. (to be published). This work was supported by NSF. *Timken Research, Canton, OH 44706-0939

Gilgenbach, R. M.; Qi, Bo; Lau, Y. Y.; Johnston, M. D.; Doll, G. L.

2000-10-01

432

Cochlear Implant Using Neural Prosthetics  

NASA Astrophysics Data System (ADS)

This research is based on neural prosthetic device. The oldest and most widely used of these electrical, and often computerized, devices is the cochlear implant, which has provided hearing to thousands of congenitally deaf people in this country. Recently, the use of the cochlear implant is expanding to the elderly, who frequently suffer major hearing loss. More cutting edge are artificial retinas, which are helping dozens of blind people see, and ìsmartî artificial arms and legs that amputees can maneuver by thoughts alone, and that feel more like real limbs.Research, which curiosity led to explore frog legs dancing during thunderstorms, a snail shapedorgan in the inner ear, and how various eye cells react to light, have fostered an understanding of how to ìtalkî to the nervous system. That understanding combined with the miniaturization of electronics and enhanced computer processing has enabled prosthetic devices that often can bridge the gap in nerve signaling that is caused by disease or injury.

Gupta, Shweta; Singh, Shashi kumar; Dubey, Pratik Kumar

2012-10-01

433

Hallux rigidus: cheilotomy or implant?  

PubMed

Fifty-one feet in 42 patients with varying degrees of symptomatic hallux rigidus and with 2 years of follow-up have been operated with excellent results. Cheilotomy was performed in all cases with only cheilotomy employed in the young patients and implant surgery (single-stem silicone) reserved for the older and more advanced arthritis cases. Pain generally disappeared within 3 months. Range of toe motion in dorsiflexion increased. All patients returned to their activity of choice. All patients were able to utilize off-the-shelf footwear postoperatively. There have been no fractures or inflammatory reactions of the implants as yet, including those inserted 4 or more years ago. PMID:7349857

Gould, N

1981-05-01

434

Implantable telemetry for small animals  

NASA Technical Reports Server (NTRS)

A series of totally implantable telemetry devices for use in measuring deep body parameters in small animals were developed. Under a collaborative agreement with NASA, several of these systems; the continuous wave Doppler ultrasonic flowmeter, the multichannel telemetry system, and the inductively-powered dual channel cardiac pacer were evaluated in a series of ten mongrel dogs (15 to 20 kg.). These systems were used to measure ascending aortic and coronary blood flow, aortic pressure, and subcutaneous EKG.

1982-01-01

435

Assessment of interleukin-1beta and interleukin-6 in the crevicular fluid around healthy implants, implants with peri-implantitis, and healthy teeth: a cross-sectional study  

PubMed Central

Objectives This study aimed to assess and compare the levels of interleukin-1beta (IL-1?) and interleukin-6 (IL-6) in the crevicular fluid around healthy implants, implants with peri-implantitis, and healthy teeth. Materials and Methods This study evaluated 16 dental implants in 8 patients (4 males and 4 females). These patients had at least one healthy implant and one implant with peri-implantitis next to healthy teeth. The crevicular fluid was collected using absorbent cones and transferred to the laboratory. Specimens were evaluated by ELISA for interleukin levels. Data were analyzed using repeated measures ANOVA and Bonferroni tests (P<0.05). Results Levels of IL-1? in the crevicular fluid around implants with peri-implantitis were significantly higher than around healthy implants (P=0.002); the latter was significantly higher than around healthy teeth (P=0.015). A significant difference was found in the level of IL-6 in the crevicular fluid around implants with peri-implantitis and healthy implants (P=0.049) and also between implants with peri-implantitis and healthy teeth (P<0.001). Conclusion Within the limitations of this study, significant differences exist in the levels of IL-1? and IL-6 in the crevicular fluid of implants with peri-implantitis, healthy implants, and healthy teeth. More studies with larger sample sizes in different populations are necessary. PMID:25368834

Yaghobee, Siamak; Khorsand, Afshin; Rasouli Ghohroudi, Amir Alireza; Sanjari, Khashayar

2014-01-01

436

Interstitial implant with interstitial hyperthermia  

SciTech Connect

A Phase I Pilot Study combining interstitial or intracavitary irradiation using /sup 192/Ir or /sup 137/Cs and interstitial hyperthermia in advanced or recurrent tumors is underway at the City of Hope National Medical Center. Hyperthermia is performed using 0.5 megahertz RF (500 kilohertz) radiofrequency localized current fields. In the implanted volume, a temperature of 41/sup 0/ to 45/sup 0/C is maintained for 30 to 40 minutes. Hyperthermia is performed prior to irradiation in all patients. All patients had either failed previous conventional treatments, including surgery, chemotherapy and/or radiation therapy, or had advanced malignant tumors which were not felt to be controllable by conventional means. Sixteen lesions were implanted in 15 patients. Of the 16 lesions, 11/16 (68%) achieved complete response, and three had no response or recurred locally. The six patients (100%) receiving interstitial implant and hyperthermia as the primary therapy achieved complete response. Normal tissue complications were minimal. Range of response was three to 13 months. Interstitial thermoradiotherapy appears to be a safe and promising mode of therapy in advanced or recurrent accessible malignant tumors.

Vora, N.; Forell, B.; Joseph, C.; Lipsett, J.; Archambeau, J.D.

1982-12-01

437

Ion implantation damage in solids  

NASA Astrophysics Data System (ADS)

Ion implantation damage in silicon and ion irradiation induced surface smoothing and roughening process on metal and metallic alloys were studied. Defects were produced in Si by ion implantation. The initial state of damage, the onset temperature of interstitial mobility, the broader annealing behavior of the defects and the effect of surface on damage accumulation were studied using diffuse X-ray scattering, high resolution X-ray diffraction and transmission electron microscopy methods. A critical dose was observed during self-ion irradiation at 100°C for the conversion of small three-dimensional clusters in two-dimensional dislocation loops. The annealing behavior following self-ion irradiations shows different behavior from that following irradiation with inert gas ions. The surface was shown to be an effective sink for defects and that it plays an important role in defect accumulation during low energy implantation. Ion induced surface smoothing and roughening processes were studied using Molecular Dynamics (MD) computer simulation. The simulations on self-ion bombarded W showed the effect of the surface on defect production and the roughening of the surface. The simulations on the CuTi, Ag and Ni with amorphous and crystalline states reveal the smoothing and roughening process due to a single ion impact.

Zhong, Yuncheng

438

Immediate implants in anterior maxillary arch  

PubMed Central

Aim: The aim of the study was to evaluate the osseo-integration and soft tissue status of the endosseous implants placed in immediate extraction socket. Methodology: Seven patients (4 males and 3 females) aged 20-30 years were selected for the study. Nine implants were placed in seven patients in the maxillary arch. All the patients were clinically ?nd thoroughly examined. Under local anesthesia, the indicated tooth was extracted. The extracted socket was prepared using standard drills with palatal wall as guide. The longest and widest implants were placed (Hi-Tec Implants). All implants showed good primary stability. The implants used in the study were tapered design endosseous implants with Threaded implants (TI) unit plasma-sprayed surface. Surgical re-entry (secondary surgery) was performed to remove the healing cap after 6 months for supra crestal fabrication. All patients were reviewed periodically at 3rd and 6th month interval and the following clinical parameters including modified plaque index (mPlI), modified bleeding index (mBI), probing depth (PD), attachment level (AL), and distance between the implant shoulder and mucosal margin (DIM), distance between the implant shoulder and first bone-implant contact, and Clinical Mobility Index were recorded. The results were computed and subjected to statistical evaluation. Results: The mPlI, mBI, PD, AL, and DIM were evaluated around the implants at baseline, 3rd and 6th month intervals and analyzed statistically by Friedman T-test. The results of the above were shown to be statistically non-significant. The distance between the implant shoulder and first bone implant contact was evaluated around the implants at base line, 3rd and 6th month intervals. The results proved to be statistically significant (0.01) implying that there was a bone apposition around the implants. Conclusion: During the course of the study, soft tissue status around implants was found to be healthy. Osseointegration as assessed by clinical and radiographic findings was found to be sound. PMID:24678203

Anitha, K.; Kumar, S. Senthil; Babu, M. R. Ramesh; Candamourty, Ramesh; Thirumurugan

2014-01-01

439

Reconstruction of the ossicular chain with titanium implants  

Microsoft Academic Search

Objectives: Since 1994 more than 1300 titanium implants have been used to reconstruct the ossicular chain of the middle ear for chronic otitis media. Two different types of implants were used. First, a total and a partial implant of fixed length, available in numerous different lengths. And second, a total and partial implant that has an adjustable length. The implants

C. V. Dalchow; D. Grün; H. F. Stupp

2001-01-01

440

Unalloyed titanium for implants in bone surgery.  

PubMed

Commercially pure (c.p.) titanium has proven its suitability as an implant material in bone surgery over many years in the fields of osteosynthesis, oral implantology, and in certain applications in joint prosthetics. Excellent biocompatibility and corrosion resistance are outstanding features. Furthermore, c.p. titanium is known for not causing allergic reactions. The different grades of c.p. titanium and their minimum mechanical properties are specified in ISO and ASTM standards for implant materials. Typical mechanical properties are given for AO ASIF implant applications. The properties and clinical performance of c.p. titanium are discussed and compared to those of implant stainless steel and titanium alloys. In brief some specific features relating to c.p. titanium implant material are treated, including biocompatibility and soft tissue and bone response and taking into account the effects of implant surface configurations at the same time. In addition, issues are addressed which arise from frequent inquiries from clinics. PMID:11270082

Pohler, O E

2000-12-01

441

The diagnosis of silicone breast implant rupture.  

PubMed

Magnetic resonance imaging of the breast in the diagnosis of silicone breast implant rupture is widely accepted to be the imaging study of choice for most women. Magnetic resonance imaging in the detection of silicone implant failure has been shown to have the highest sensitivity and specificity and has the ability to image the entire implant without the use of ionizing radiation. Unfortunately, some women are unable to have a magnetic resonance imaging examination of the breast because of contraindications such as cardiac pacemakers, aneurysm clips, and claustrophobia. Therefore, mammography, ultrasonography, and computed tomography will have roles in the diagnosis of silicone breast implant ruptures. This article illustrates the spectrum of imaging appearances of normal silicone gel implants and the appearances of silicone breast implant ruptures. PMID:18090814

Gorczyca, David P; Gorczyca, Stephanie M; Gorczyca, Kathryn L

2007-12-01

442

Cluster ion implantation for shallow junction formation  

SciTech Connect

The implantation of Ar and B into Si by cluster ion has been examined. Shallow implantation was clearly demonstrated with a high energy cluster ion. The damage layer thickness is less than 200{angstrom}, when 150keV Ar cluster ions are implanted into Si. This thickness is one order of magnitude smaller than that by Ar monomer ion bombardment with the same total energy. The thickness of the damaged layer formed by cluster ion bombardment increased with the cluster size, when the total energy of cluster ion remain the same. This is one of the non-linear effect of cluster implantation. Poly-atomic cluster-ion implantation with decaborane has also been demonstrated. Shallow implantation (<0.05 {mu}m) can be achieved by decaborane (B{sub 10}H{sub 14}) ions. The sheet resistance of the sample reached a few hundred {Omega}/{open_square} after annealing at 1000{degrees}C for 10s.

Matsuo, Jiro; Takeuchi, Daisuke; Aoki, Takaaki; Yamada, Isao [Kyoto Univ., Sakyo (Japan)

1996-12-31

443

Patients, Pacemakers, and Implantable Defibrillators: Human Values and Security for Wireless Implantable  

E-print Network

Terms Design, Human Factors, Security. INTRODUCTION Implantable medical devices (IMDs), such as pacemak Implantable Medical Devices Tamara Denning , Alan Borning , Batya Friedman , Brian T. Gill , Tadayoshi Kohno of Washington Department of Mathematics, Seattle Pacific University + Medical Device Safety Institute, Beth

Anderson, Richard

444

The Bone-Forming Effects of HIF-1?-Transduced BMSCs Promote Osseointegration with Dental Implant in Canine Mandible  

PubMed Central

The presence of insufficient bone volume remains a major clinical problem for dental implant placement to restore the oral function. Gene-transduced stem cells provide a promising approach for inducing bone regeneration and enhancing osseointegration in dental implants with tissue engineering technology. Our previous studies have demonstrated that the hypoxia-inducible factor-1? (HIF-1?) promotes osteogenesis in rat bone mesenchymal stem cells (BMSCs). In this study, the function of HIF-1? was validated for the first time in a preclinical large animal canine model in term of its ability to promote new bone formation in defects around implants as well as the osseointegration between tissue-engineered bone and dental implants. A lentiviral vector was constructed with the constitutively active form of HIF-1? (cHIF). The ectopic bone formation was evaluated in nude mice. The therapeutic potential of HIF-1?-overexpressing canine BMSCs in bone repair was evaluated in mesi-implant defects of immediate post-extraction implants in the canine mandible. HIF-1? mediated canine BMSCs significantly promoted new bone formation both subcutaneously and in mesi-implant defects, including increased bone volume, bone mineral density, trabecular thickness, and trabecular bone volume fraction. Furthermore, osseointegration was significantly enhanced by HIF-1?-overexpressing canine BMSCs. This study provides an important experimental evidence in a preclinical large animal model concerning to the potential applications of HIF-1? in promoting new bone formation as well as the osseointegration of immediate implantation for oral function restoration. PMID:22403648

Zou, Duohong; He, Jiacai; Zhang, Kai; Dai, JieWen; Zhang, Wenjie; Wang, Shaoyi; Zhou, Jian; Huang, Yuanliang

2012-01-01

445

ECT-induced Mania  

PubMed Central

Electroconvulsive therapy can induce mania. A recent change in the Diagnostic and Statistical Manuel of Mental Disorders, Fifth Edition classifies electroconvulsive therapy-induced manic episodes as a bipolar type I diagnosis. There are no current established guidelines to treat such condition. The following clinical vignette describes a vignette in which a manic episode occurred following electroconvulsive therapy treatment. This case report examines the potential benefit of prescribing mood stabilizers during the acute episode and for maintenance care.

Lee, Jae; Arcand, Laura; Narang, Puneet

2014-01-01

446

Pulsed source ion implantation apparatus and method  

DOEpatents

A new pulsed plasma-immersion ion-implantation apparatus that implants ions in large irregularly shaped objects to controllable depth without overheating the target, minimizing voltage breakdown, and using a constant electrical bias applied to the target. Instead of pulsing the voltage applied to the target, the plasma source, for example a tungsten filament or a RF antenna, is pulsed. Both electrically conducting and insulating targets can be implanted. 16 figs.

Leung, K.N.

1996-09-24

447

Pulsed source ion implantation apparatus and method  

DOEpatents

A new pulsed plasma-immersion ion-implantation apparatus that implants ions in large irregularly shaped objects to controllable depth without overheating the target, minimizing voltage breakdown, and using a constant electrical bias applied to the target. Instead of pulsing the voltage applied to the target, the plasma source, for example a tungsten filament or a RF antenna, is pulsed. Both electrically conducting and insulating targets can be implanted.

Leung, Ka-Ngo (Hercules, CA)

1996-01-01

448

Antibacterial iodine-supported titanium implants  

Microsoft Academic Search

Deep infection remains a serious complication in orthopedic implant surgery. In order to reduce the incidence of implant-associated infections, several biomaterial surface treatments have been proposed. This study focused on evaluating the antibacterial activity of iodine-supported titanium (Ti–I2) and its impact on post-implant infection, as well as determining the potential suitability of Ti–I2 as a biomaterial. External fixation pins were

T. Shirai; T. Shimizu; K. Ohtani; Y. Zen; M. Takaya; H. Tsuchiya

2011-01-01

449

Effect of phosphorus ion implantation on back gate effect of partially depleted SOI NMOS under total dose radiation  

NASA Astrophysics Data System (ADS)

The mechanism of improving the TID radiation hardened ability of partially depleted silicon-on-insulator (SOI) devices by using the back-gate phosphorus ion implantation technology is studied. The electron traps introduced in SiO2 near back SiO2/Si interface by phosphorus ions implantation can offset positive trapped charges near the back-gate interface. The implanted high concentration phosphorus ions can greatly reduce the back-gate effect of a partially depleted SOI NMOS device, and anti-total-dose radiation ability can reach the level of 1 Mrad(Si) for experimental devices.

Leilei, Li; Xinjie, Zhou; Zongguang, Yu; Qing, Feng

2015-01-01

450

Influence of prosthesis design and implantation technique on implant stresses after cementless revision THR  

Microsoft Academic Search

Background  Femoral offset influences the forces at the hip and the implant stresses after revision THR. For extended bone defects, these\\u000a forces may cause considerable bending moments within the implant, possibly leading to implant failure. This study investigates\\u000a the influences of femoral anteversion and offset on stresses in the Wagner SL revision stem implant under varying extents\\u000a of bone defect conditions.

Markus O Heller; Manav Mehta; William R Taylor; Dong-Yeong Kim; Andrew Speirs; Georg N Duda; Carsten Perka

2011-01-01

451

Fig. 1. (a) Cochlea implant system and (b) Cochlea anatomy Abstract--Robot-assisted cochlear implant surgery was  

E-print Network

--Robot-assisted cochlear implant surgery was proposed and proved to be efficient in reducing insertion forces on acrylic implant surgeries. I. INTRODUCTION ULTI-CHANNEL cochlear implants have been developed for more than 30 cochlear implant surgery. The cochlear implant system includes a microphone, a micro

Simaan, Nabil

452

Implantation failure: molecular mechanisms and clinical treatment  

PubMed Central

BACKGROUND Implantation is a complex initial step in the establishment of a successful pregnancy. Although embryo quality is an important determinant of implantation, temporally coordinated differentiation of endometrial cells to attain uterine receptivity and a synchronized dialog between maternal and embryonic tissues are crucial. The exact mechanism of implantation failure is still poorly understood. METHODS This review summarizes the current knowledge about the proposed mechanisms of implantation failure in gynecological diseases, the evaluation of endometrial receptivity and the treatment methods to improve implantation. RESULTS The absence or suppression of molecules essential for endometrial receptivity results in decreased implantation rates in animal models and gynecological diseases, including endometriosis, hydrosalpinx, leiomyoma and polycystic ovarian syndrome. The mechanisms are diverse and include abnormal cytokine and hormonal signaling as well as epigenetic alterations. CONCLUSIONS Optimizing endometrial receptivity in fertility treatment will improve success rates. Evaluation of implantation markers may help to predict pregnancy outcome and detect occult implantation deficiency. Treating the underlying gynecological disease with medical or surgical interventions is the optimal current therapy. Manipulating the expression of key endometrial genes with gene or stem cell-based therapies may some day be used to further improve implantation rates. PMID:20729534

Cakmak, Hakan; Taylor, Hugh S.

2011-01-01

453

Flapless implant placement: a case report.  

PubMed

Full-thickness periosteal flap elevation for implant placement is often accompanied by potential marginal bone loss and/or soft tissue recession around the implant due to compromised blood supply to underlying bone. To preserve the blood supply to underlying bone, implants can be placed with a flapless surgical procedure. This procedure also provides numerous other benefits, such as decreased trauma, short recovery time, less pain, reduced rate of infection, and improved patient compliance. This report presents a case of flapless implant placement in the mandibular posterior region that achieved optimum results and caused minimal discomfort to the patient. The advantages and limitations of this procedure are also discussed. PMID:24914919

Jain, Deshraj; Gaur, Ghanshyam

2014-06-01

454

[Consensus on peri-implant infections].  

PubMed

In 2008, in a workshop of the European Federation on Periodontology, a consensus was reached concerning oral peri-implant infections on the basis of the state of the art in the relevant sciences. Important conclusions were that peri-implant mucositis occurs in 80% of subjects with oral implants, and that peri-implantitis occurs in 28-56% of subjects studied. Important risk factors for developing peri-implant infections seem to be insufficient oral hygiene, a history of periodontitis and cigarette smoking. There are insufficient research findings available to support a definitive conclusion about the role of genetic factors, diabetes mellitus, alcohol consumption and implant surface properties. Mechanical treatment in combination with antimicrobial oral mouth rinses may be effective in the treatment of mucositis. No evidence has been found that mechanical treatment of peri-implantitis is effective. To control the infection of peri-implantitis, surgical treatment, often in combination with the use of local or systemic antibiotics, is necessary. Validated protocols for the treatment of peri-implant infections are not available due to lack of clinical scientific evidence. PMID:21077390

van Winkelhoff, A J

2010-10-01

455

Physical modification of polyetheretherketone for orthopedic implants  

NASA Astrophysics Data System (ADS)

Polyetheretherketone (PEEK) is regarded as one of the most potential candidates for replacing current implant applications. To obtain good bone-implant interfaces, many modification methods have been developed to enable PEEK and PEEK-based composites from bio-inert to bioactive. Among them, physical methods have aroused significant attention and been widely used to modify PEEK for orthopedic implants. This review summarizes current physical modification techniques of PEEK for orthopedic applications, which include composite strategies, surface coating methods and irradiation treatments. The positive consequences of those modification methods will encourage continuing investigations and stimulate the wide range of applications of PEEK-based implants in orthopedics.

Du, Ya-Wei; Zhang, Li-Nan; Hou, Zeng-Tao; Ye, Xin; Gu, Hong-Sheng; Yan, Guo-Ping; Shang, Peng

2014-12-01

456

Techniques for dental implant nanosurface modifications  

PubMed Central

PURPOSE Dental implant has gained clinical success over last decade with the major drawback related to osseointegration as properties of metal (Titanium) are different from human bone. Currently implant procedures include endosseous type of dental implants with nanoscale surface characteristics. The objective of this review article is to summarize the role of nanotopography on titanium dental implant surfaces in order to improve osseointegration and various techniques that can generate nanoscale topographic features to titanium implants. MATERIALS AND METHODS A systematic electronic search of English language peer reviewed dental literature was performed for articles published between December 1987 to January 2012. Search was conducted in Medline, PubMed and Google scholar supplemented by hand searching of selected journals. 101 articles were assigned to full text analysis. Articles were selected according to inclusion and exclusion criterion. All articles were screened according to inclusion standard. 39 articles were included in the analysis. RESULTS Out of 39 studies, seven studies demonstrated that bone implant contact increases with increase in surface roughness. Five studies showed comparative evaluation of techniques producing microtopography and nanotopography. Eight studies concluded that osteoblasts preferably adhere to nano structure as compared to smooth surface. Six studies illustrated that nanotopography modify implant surface and their properties. Thirteen studies described techniques to produce nano roughness. CONCLUSION Modification of dental osseous implants at nanoscale level produced by various techniques can alter biological responses that may improve osseointegration and dental implant procedures.

Bathala, Lakshmana Rao; Sangur, Rajashekar

2014-01-01

457

Scleral melt following Retisert intravitreal fluocinolone implant  

PubMed Central

Intravitreal fluocinolone acetonide implant (Retisert) has a high potency, a low solubility, and a very short duration of action in the systemic circulation, enabling the steroid pellet to be small and reducing the risk of systemic side effects. Scleral melt has not been reported as a possible complication of Retisert implant. The authors describe the occurrence of scleral melt 18 months after the implantation of fluocinolone acetonide implant in a 42-year-old Caucasian woman. To the authors’ knowledge, this is the first report of this possible complication. PMID:25489235

Georgalas, Ilias; Koutsandrea, Chrysanthi; Papaconstantinou, Dimitrios; Mpouritis, Dimitrios; Petrou, Petros

2014-01-01

458

Evaluation of the retention of endodontic implants.  

PubMed

The study investigated the retentive strength of endodontic implants measured by forced removal (pull-out or push-out tests) as a function of implant design and cement type. Smooth-tapered, threaded, and an innovative porous-surfaced implant were evaluated. Specimens were cemented in single-rooted human teeth with five different cements: zinc phosphate, polycarboxylate, glass ionomer, silicophosphate, or AH-26. The results indicated superior retention for the threaded and porous-surfaced implants, and stronger retention with glass-ionomer and AH-26 cements. PMID:3162990

Maniatopoulos, C; Pilliar, R M; Smith, D C

1988-04-01

459

Implant-supported fixed restoration of post-traumatic mandibular defect accompanied with skin grafting: A clinical report  

PubMed Central

Traumatic defects are mostly accompanied by hard and soft tissue loss. This report describes the surgical and prosthetic treatment of a patient with post-traumatic mandibular defect. A split-thickness skin graft was performed prior to implant placement and prefabricated acrylic stent was placed to hold the graft in place. The esthetic and functional demands of the patient were fulfilled by implant-supported screw-retained fixed prosthesis using CAD-CAM technology. PMID:23508120

Noh, Kwantae; Choi, Woo-Jin

2013-01-01

460

Short-term evaluation of dental implants in a diabetic population: an in vivo study  

PubMed Central

PURPOSE The study was conducted to evaluate the efficacy of implant supported tooth replacement in diabetic patients. MATERIALS AND METHODS The study involved placement of implants (UNITI implants, Equinox Medical Technologies, Zeist, Holland, diameter of 3.7 mm and length 13 mm) in five diabetic patients (three females and two males) of age ranging from 35-65 years with acceptable metabolic control of plasma glucose. All patients included in the study were indicated for single tooth maxillary central incisor replacement, with the adjacent teeth intact. The survival of the restored implants was assessed for a period of three months by measurement of crestal bone heights, bleeding on probing and micro flora predominance. Paired t-test was done to find out the difference in the microbial colonization, bleeding on probing and crestal bone loss. P values of less than 0.05 were taken to indicate statistical significance. RESULTS Results indicated that there was a significant reduction in bleeding on probing and colonization at the end of three months and the bone loss was not statistically significant. CONCLUSION The study explores the hypothesis that patients with diabetes are appropriate candidates for implants and justifies the continued evaluation of the impact of diabetes on implant success and complications. PMID:22977720

Veeravalli, Padmanabhan Thallam; Vaidyanathan, Anand Kumar; Grover, Manita

2012-01-01

461

Remotely powered, multichannel, microprocessor based telemetry systems for a smart implantable total knee implant  

Microsoft Academic Search

The development of improved implantable devices and materials requires knowledge of their in vivo behavior. However, little is known about the actual loads borne by implanted devices in vivo. Direct load measurement would provide extremely valuable information, for the improvement of device designs, and for the rapid rehabilitation of individuals in which devices have been implanted. Multichannel telemetry systems, combined

Christopher P. Townsend; Steven W. Arms; Michael J. Hamel

462

Implants and Decoding for Intracortical Brain Computer Interfaces  

PubMed Central

Intracortical brain computer interfaces (iBCIs) are being developed to enable a person to drive an output device, such as a computer cursor, directly from their neural activity. One goal of the technology is to help people with severe paralysis or limb loss. Key elements of an iBCI are the implanted sensor that records the neural signals and the software which decodes the user’s intended movement from those signals. Here, we focus on recent advances in these two areas, with special attention being placed on contributions that are or may soon be adopted by the iBCI research community. We discuss how these innovations increase the technology’s capability, accuracy, and longevity, all important steps that are expanding the range of possible future clinical applications. PMID:23862678

Homer, Mark L.; Nurmikko, Arto V.; Donoghue, John P.; Hochberg, Leigh R.

2014-01-01

463

Energy conservation potential of surface modification technologies  

SciTech Connect

This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

Le, H.K.; Horne, D.M.; Silberglitt, R.S.

1985-09-01

464

A Nano Power CMOS Tinnitus Detector for a Fully Implantable Closed-Loop Neurodevice  

E-print Network

Biomedical Electronics Group, Electronics Research Laboratory, Delft University of Technology of life of the patients [1] and can lead to insomnia [2], anxiety [3] and depression [4]. Currently. In order to deliver electrical brain stimulation therapy, implantable pulse generators (IPGs) are used

Serdijn, Wouter A.

465

Titanium implants with oxidized surfaces: the background and long-term results  

Microsoft Academic Search

The purpose of this paper is to give an overview of different implant surface modification technologies—including the presentation of a new technique, involving the formation of a ceramic titanium oxide coating. Three techniques are used to modify metal surfaces: (1) addition of material, (2) removal of material and (3) modification of material already present, e.g. by means of laser or

Christian Toth; György Szabó; Lajos Kovács; Kálmán Vargha; József Barabás; Zsolt Németh

2002-01-01

466