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1

Emulsion Chamber Technology Experiment (ECT)  

NASA Technical Reports Server (NTRS)

The experimental objective of Emulsion Chamber Technology (ECT) was to develop space-borne emulsion chamber technology so that cosmic rays and nuclear interactions may subsequently be studied at extremely high energies with long exposures in space. A small emulsion chamber was built and flown on flight STS-62 of the Columbia in March 1994. Analysis of the several hundred layers of radiation-sensitive material has shown excellent post-flight condition and suitability for cosmic ray physics analysis at much longer exposures. Temperature control of the stack was 20 +/-1 C throughout the active control period and no significant deviations of temperature or pressure in the chamber were observed over the entire mission operations period. The unfortunate flight attitude of the orbiter (almost 90% Earth viewing) prevented any significant number of heavy particles (Z greater than or equal to 10) reaching the stack and the inverted flow of shower particles in the calorimeter has not allowed evaluation of absolute primary cosmic ray-detection efficiency nor of the practical time limits of useful exposure of these calorimeters in space to the level of detail originally planned. Nevertheless, analysis of the observed backgrounds and quality of the processed photographic and plastic materials after the flight show that productive exposures of emulsion chambers are feasible in low orbit for periods of up to one year or longer. The engineering approaches taken in the ECT program were proven effective and no major environmental obstacles to prolonged flight are evident.

Gregory, John C.; Takahashi, Yoshiyuki

1996-01-01

2

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

3

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

4

Advances in lens implant technology.  

PubMed

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

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

2013-01-01

5

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.

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

2013-01-01

6

Ion Implantation Processing Technologies for Telecommunications Electronics  

SciTech Connect

The subject CRADA was a collaboration between Oak Ridge National Laboratory and Bell Laboratories, Lucent Technologies (formerly AT and T Bell Laboratories) to explore the development of ion implantation technologies for silicon integrated circuit (IC) manufacturing.

Haynes, T.E.

2000-05-01

7

RFID technology for human implant devices  

NASA Astrophysics Data System (ADS)

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 communication between a passive RFID device implanted inside human body and an off-body interrogator. The two techniques (i.e., inductive coupling and electromagnetic coupling) currently used for wirelessly supplying power to and read data from a passive implantable RFID device are described and some documented biomedical and therapeutic applications of human RFID-implant devices are finally reported.

Aubert, Hervé

2011-09-01

8

Ion implantation technology and ion sources.  

PubMed

Ion implantation (I/I) technology has been developed with a great economic success of industries of VLSI (Very Large-Scale Integrated circuit) devices. Due to its large flexibility and good controllability, the I/I technology has been assuming various challenging requirements of VLSI evolutions, especially in advanced evolutional characteristics of CMOSFET. Here, reviewing the demands of VLSI manufacturing to the I/I technology, required characteristics of ion implanters, and their ion sources are discussed. PMID:24593652

Sugitani, Michiro

2014-02-01

9

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

10

Implantable micropump technologies for murine intracochlear infusions  

Microsoft Academic Search

Due to the very small size of the mouse inner ear, 600 nL volume, developing effective, controlled infusion systems is quite challenging. Key technologies have been created to minimize both size and power for an implantable pump for murine intracochlear infusions. A method for coupling fine capillary tubing to microfluidic channels is presented which provides low volume, biocompatible interconnects withstanding

D. G. Johnson; M. J. Waldron; R. D. Frisina; D. A. Borkholder

2010-01-01

11

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

12

Technologic advances in implantable cardioverter defibrillators.  

PubMed

Multiple technologic advances in the implantable cardioverter defibrillator (ICD) have resulted in smaller size, easier implantation, and improved detection, therapy, and stored diagnostic information. Advanced dual-chamber ICDs are currently available that allow dual-chamber rate-responsive pacing with mode switching, enhanced detection algorithms, antitachycardia pacing, low-energy cardioversion, high-energy shocks, and extensive diagnostics. Based on improvements in lead systems and improved energy waveforms, almost all devices are being implanted with nonthoracotomy leads in the pectoralis area. The results of recent clinical trials have expanded indications for the ICD for primary and secondary prevention of sudden cardiac death. With advances in capacitor and battery technology coupled with improved lead systems and waveform resulting in lower defibrillation thresholds, it is likely that lower-output, smaller devices will be developed. In the future, ICDs may have expanded indications and may incorporate physiologic sensors to access hemodynamic significance of arrhythmias and algorithms for prediction and prevention of cardiac arrhythmias. PMID:9932202

Swygman, C A; Homoud, M K; Link, M S; Wang, P J; Estes, N A

1999-01-01

13

Implantable micropump technologies for murine intracochlear infusions.  

PubMed

Due to the very small size of the mouse inner ear, 600 nL volume, developing effective, controlled infusion systems is quite challenging. Key technologies have been created to minimize both size and power for an implantable pump for murine intracochlear infusions. A method for coupling fine capillary tubing to microfluidic channels is presented which provides low volume, biocompatible interconnects withstanding pressures as high as 827 kPa (120 psi) and consuming less than 20 nL of volume exiting in-plane with the pump. Surface micromachined resistive bridges integrated into the flow channel for anemometry based flow rate measurement have been optimized for low power operation in the ultra-low flow rate regime. A process for creation of deformable diaphragms over pump chambers with simultaneous coating of the microfluidic channels has been developed allowing integration of a biocompatible fluid flow path. These advances represent enabling capabilities for a drug delivery system suitable for space constrained applications such as subcutaneous implantation in mice. PMID:21096713

Johnson, D G; Waldron, M J; Frisina, R D; Borkholder, D A

2010-01-01

14

Implantable Micropump Technologies for Murine Intracochlear Infusions  

PubMed Central

Due to the very small size of the mouse inner ear, 600 nL volume, developing effective, controlled infusion systems is quite challenging. Key technologies have been created to minimize both size and power for an implantable pump for murine intracochlear infusions. A method for coupling fine capillary tubing to microfluidic channels is presented which provides low volume, biocompatible interconnects withstanding pressures as high as 827 kPa (120 psi) and consuming less than 20 nL of volume exiting in-plane with the pump. Surface micromachined resistive bridges integrated into the flow channel for anemometry based flow rate measurement have been optimized for low power operation in the ultra-low flow rate regime. A process for creation of deformable diaphragms over pump chambers with simultaneous coating of the microfluidic channels has been developed allowing integration of a biocompatible fluid flow path. These advances represent enabling capabilities for a drug delivery system suitable for space constrained applications such as subcutaneous implantation in mice.

Johnson, D. G.; Waldron, M. J.; Frisina, R. D.; Borkholder, D. A.

2011-01-01

15

Semiconductor Technology of Ion Implanted Silicon Devices.  

National Technical Information Service (NTIS)

The influence of ion implantion on various processes in the production of bipolar silicon devices was investigated. Results show that the oxidation behavior of ion implanted silicon layers exhibits an enhancement of the oxidation rate depending on ion spe...

J. Goetzlich A. Heuberger H. Kranz B. Schubert F. Soller

1979-01-01

16

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.

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

2010-01-01

17

Orthopaedic implant technology: biomaterials from past to future.  

PubMed

Orthopaedic implant technology is heavily based on the development and use of biomaterials. These are non-living materials (e.g. metals, polymers and ceramics) that are introduced into the human body as constituents of implants that fulfill or replace some important function. Examples would be prosthetic joint replacements and fracture fixation implants. For orthopaedic biomaterials to succeed in their desired functions and outcomes in the body, a number of factors need to be considered. The most obvious mechanical properties of the implants are that they need to suit their intended function, and various classes and types of biomaterials have been developed and characterised for use in different implant components depending on their demands. Less well understood but no less important are the interactions that occur between the constituent biomaterials and the living cells and tissues, both of the human host as well as pathogens such as bacteria. Biomaterials used for orthopaedic applications are generally considered to be biocompatible. However, adverse effects arising from interactions at the implant interface can result in various modes of implant failure, such as aseptic loosening and implant infection. This review paper uses the illustrative example of total hip replacement (which has been called the operation of the century) to highlight key points in the evolution of orthopaedic biomaterials. It will also examine research strategies that seek to address some of the major problems that orthopaedic implant surgery are facing today. PMID:21678015

Wang, Wilson; Ouyang, Youheng; Poh, Chye Khoon

2011-05-01

18

Medical student attitudes and knowledge about ECT.  

PubMed

We report the results of a survey of second-year medical students concerning attitudes and basic knowledge of electroconvulsive therapy (ECT). It appeared that there were significant negative biases against ECT in a portion of the group. Forty percent of the students who participated felt that psychiatrists often misused ECT, while 31% actually thought ECT was used to punish violent or uncooperative patients. Few students knew the typical frequency or duration of treatment or even that it was done under general anesthesia. It was interesting that the group describing themselves as highly knowledgeable about psychiatric illness had a greater bias against ECT. Students in the negative group did not differ in the sources of their information about ECT. The most common sources of this information about ECT were movies or college classes. The results document the need for appropriate coverage of ECT in medical school curriculum. PMID:11417934

Clothier, J L; Freeman, T; Snow, L

2001-06-01

19

Ion sources for ion implantation technology (invited).  

PubMed

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. PMID:24593650

Sakai, Shigeki; Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki

2014-02-01

20

GaAs FET Device Fabrication and Ion Implantation Technology.  

National Technical Information Service (NTIS)

Microwave device fabrication and evaluation in conjunction with ion implantation has been selected to provide a benchmark technology for evaluation of semi-insulating GaAs and InP grown at NRL and elsewhere. Devices have been processed by a combination of...

K. J. Sleger H. B. Dietrich

1980-01-01

21

The family caregiving experience of outpatient ECT  

Microsoft Academic Search

BackgroundGiven its safety and efficacy, electroconvulsive therapy (ECT) is increasingly being provided on an outpatient basis. However, there is limited understanding about the educational needs of the family in providing care to one of its members who is receiving outpatient ECT.

Stephanie Sethi; Reg Arthur Williams

2003-01-01

22

GaAS FET device fabrication and ion implantation technology  

Microsoft Academic Search

Microwave device fabrication and evaluation in conjunction with ion implantation has been selected to provide a benchmark technology for evaluation of semi-insulating GaAs and InP grown at NRL and elsewhere. Devices have been processed by a combination of conventional contact photolithography and liftoff techniques to achieve geometries with linewidths as small as 0.8 microns. A plasma deposited layer of Si3N4

K. J. Sleger; H. B. Dietrich

1980-01-01

23

Future technology in cochlear implants: assessing the benefit.  

PubMed

It has been over 50 years since Djourno and Eyries first attempted electric stimulation in a patient with deafness. Over this time, the Cochlear Implant (CI) has become not only remarkably successful, but increasingly complex. Although the basic components of the system still comprise an implanted receiver stimulator and electrode, externally worn speech processor, microphone, control system, and power source, there are now several alternative designs of these components with different attributes that can be variably combined to meet the needs of specific patient groups. Development by the manufacturers has been driven both by these various patient needs, and also by the desire to achieve technological superiority, or at least differentiation, ultimately in pursuit of market share. Assessment of benefit is the responsibility of clinicians. It is incumbent on both industry and clinicians to ensure appropriate, safe, and affordable introduction of new technology. For example, experience with the totally implanted cochlear implant (TIKI) has demonstrated that quality of hearing is the over-riding consideration for CI users. To date, improved hearing outcomes have been achieved by improvements in: speech processing strategies; microphone technology; pre-processing strategies; electrode placement; bilateral implantation; use of a hearing aid in the opposite ear (bimodal stimulation); and the combination of electric and acoustic stimulation in the same ear. The resulting expansion of CI candidacy, with more residual hearing, further improves the outcomes achieved. Largely facilitated by advances in electronic capability and computerization, it can be expected that these improvements will continue. However, marked variability of results still occurs and we cannot assure any individual patient of their outcome. Realistic goals for implementation of new technology include: improved hearing in noise and music perception; effective invisible hearing (no external apparatus); automated fitting; and reduction in outcome variability. This paper provides examples of relevant potential future technologies that can be applied to reach these goals. In the quest for better outcomes, future technology must deliver improved reliability and usability for both clinicians and recipients that does not compromise safety and is affordable. One of the challenges related to the introduction of new technologies is the 'classification' of CI systems and the framework under which sufficient change and increased benefit can be demonstrated to establish a claim of 'new generation CI' and hence increased reimbursement from third-party payers. Significant improvements in hearing outcomes and quality of life associated with CI design changes are difficult to measure, particularly when there is such dramatic benefit from the intervention of cochlear implantation from the individual's perspective. Manufacturers and clinicians need to be objective and undertake appropriate safety studies and long-term and multi-centre clinical trials to ensure that the introduction of new technology is both safe and effective and supported by health systems worldwide. PMID:21756467

Briggs, Robert J S

2011-05-01

24

GaAS FET device fabrication and ion implantation technology  

NASA Astrophysics Data System (ADS)

Microwave device fabrication and evaluation in conjunction with ion implantation has been selected to provide a benchmark technology for evaluation of semi-insulating GaAs and InP grown at NRL and elsewhere. Devices have been processed by a combination of conventional contact photolithography and liftoff techniques to achieve geometries with linewidths as small as 0.8 microns. A plasma deposited layer of Si3N4 has been employed as an annealing encapsulant at temperatures between 800 C and 850 C for 15-30 minutes (GaAs) or 700 C - 750 C for 15 minutes (InP). Si and Se were used as the principal implant species. During this period, the Si3N4 encapsulation process and the fabrication of GaAs FETs with one micron gate lengths and noise figures below 2.4 dB at 6 GHz have become routine. Difference in microwave performance between ion implanted channel and epitaxial channel (industrially supplied) GaAs FETs was systematically correlated with various materials parameters such as mobility and light sensitivity and with static FET characteristics such as looping, backside gating, pinch-off voltage and transconductance. Experimental results indicate that good microwave performance can be obtained even though a few of the static or material characteristics are independently judged to be substandard.

Sleger, K. J.; Dietrich, H. B.

1980-06-01

25

Implants  

MedlinePLUS

... root-form implants were placed in people. Other types of implants also have been used for the last 30 to 40 years. Many implant systems are available from various dental manufacturers. Success Studies ...

26

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

27

Production technology for high efficiency ion implanted solar cells  

NASA Technical Reports Server (NTRS)

Ion implantation is being developed for high volume automated production of silicon solar cells. An implanter designed for solar cell processing and able to properly implant up to 300 4-inch wafers per hour is now operational. A machine to implant 180 sq m/hr of solar cell material has been designed. Implanted silicon solar cells with efficiencies exceeding 16% AM1 are now being produced and higher efficiencies are expected. Ion implantation and transient processing by pulsed electron beams are being integrated with electrostatic bonding to accomplish a simple method for large scale, low cost production of high efficiency solar cell arrays.

Kirkpatrick, A. R.; Minnucci, J. A.; Greenwald, A. C.; Josephs, R. H.

1978-01-01

28

GaAs FET device fabrication and ion implantation technology (microwave 3-5 compound semiconductors)  

Microsoft Academic Search

Microwave Schottky barrier FETs and ion implantation have been selected to provide a bench mark technology for evaluation of III-V compound semiconductor materials grown at NRL and elsewhere. FETs used here employ a nominal one micron gate length and are processed by a combination of conventional contact photolithography and liftoff techniques. Ion implantation studies have centered about creating doping profiles

K. J. Sleger; H. B. Dietrich

1979-01-01

29

THE NIMHANS MODEL ECT INSTRUMENT: A TECHNICAL REPORT  

PubMed Central

SUMMARY The importance of electrical dose measurement (“dosimetry”) during electroconvulsive therapy (ECT) has been gaining recognition. There is a need to explicitly provide full details of the electrical stimulus used during ECT. The conventional sinewave ECT stimulators in use in our country suffer from some limitations in this regard. To overcome these, a new model of ECT instrument was designed to deliver unmodified, bidirectional sinewave stimuli, with facilities for measuring the electrical dose incorporated into the instrument. The report outlines the features of this model of ECT instrument, and describes the dosimetric observations carried out in preclinical and clinical settings.

Gangadhar, B.N.; Laxmanna, G.; Andrade, C.; Janakiramaiah, G.; Channabasavanna, S.M.

1988-01-01

30

Visualization of Flow Pattern in Thermosyphon by ECT  

NASA Astrophysics Data System (ADS)

An investigation on the visualization of the flow of the liquid in a two-phase closed thermosyphon (TPCT) is carried out. Electrical capacitance tomography (ECT) with optimal step lengths for iterative image reconstruction algorithm is applied in the study. Measurements are made under a range of heating rates of the TPCT. As against the common assumption of ``low spatial resolution of ECT'', the experimental results have demonstrated ECT's capability of reconstructing images of thin films on the order of 100 ?m in thickness. Results for film thickness by ECT are compared with the established theory. Agreements and discrepancies are observed among the reconstructed images corresponding to difference thresholds. ECT images of the liquid distributions in the TPCT show clear dependence on the variation of working conditions, which proves the potential of ECT as an advantageous technique for monitoring the operation of TPCT.

Liu, Shi; Li, Jingtao; Chen, Qi

2007-06-01

31

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.

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

1982-01-01

32

Physical morbidity with unmodified ect - a decade of experience.  

PubMed

Recent recommendations for the routine use of modified ECT prompted an audit to be undertaken to determine the incidence of musculoskeletal complications occurring in patients who received ECT at our centre from 1980 to 1990. Of the 13,597 treatments given, 98% were unmodified, due to the lack of availability of anesthetists. Musculoskeletal complications occurred in less than 1% of treatments and were of little clinical significance. However, modified ECT was associated with significantly greater frequency of potentially fatal complications such as cardiac arrest. The findings of this audit indicate that unmodified ECT administered by a trained team does not result in significant musculoskeletal morbidity and may be preferable to modified ECT in the absence of trained anaesthetic personnel. The decision to routinely recommend modified ECT in developing countries should await scientific debate with due consideration of the complications, resources, ethics, practicality and cost as well as the consequences of such a recommendation on clinical practice. PMID:21743648

Tharyan, P; Saju, P J; Datta, S; John, J K; Kuruvilla, K

1993-10-01

33

Ion sources for ion implantation technology (invited)a)  

NASA Astrophysics Data System (ADS)

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; Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki

2014-02-01

34

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

PubMed

Nanomaterials play a significant role in biomedical research and applications because of their unique biological, mechanical, and electrical properties. In recent years, they have been utilized to improve the functionality and reliability of a wide range of implantable medical devices ranging from well-established orthopedic 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 orthopedic 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 orthopedic 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 article 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

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

2013-01-01

35

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.

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

2012-01-01

36

Continuation and maintenance ECT: a review of recent research.  

PubMed

Continuation and maintenance electroconvulsive therapy (ECT) is used to reduce the risk for relapse and recurrence of illness in patients who fare poorly with continuation and maintenance medication regimens. Despite the potential value of these ECT schedules, both are relatively neglected in clinical practice. This article therefore reviews the last decade of research on the subject. Although the research comprises mostly single and multiple case reports and small open studies, continuation and maintenance ECT does emerge as a safe and effective treatment for relapse- and recurrence-prone patients who have responded to a course of ECT. PMID:12394534

Andrade, Chittaranjan; Kurinji, S

2002-09-01

37

Towards a European Credit Transfer System for Networked Learning (ECTS-NL)  

Microsoft Academic Search

In this paper an ECTS system for Network Learning (ECTS-NL) is proposed as the framework for developing Network Learning courses and studies. After a short introduction to Network Learning and the ECTS system, the necessary extensions and modifications are made to the classical ECTS system, to create an ECTS-NL system that is both capable to provide the underlying structure for

Theodoros Kargidis; Petros Kefalas; Demosthenes Stamatis; Athanasios Tsadiras

38

The ObjECTS: Framework for Integrated Assessment: Hybrid Modeling of Transportation  

Microsoft Academic Search

Technology is a central issue for the global climate change problem, requiring analysis tools that can examine the impact of specific technologies with a long-term, global context. This paper describes the architecture of the ObjECTS-MiniCAM integrated assessment model, which implements a long-term, global model of energy, economy, agriculture, land-use, atmosphere, and climate change in a framework that allows the flexible

Son H. Kim; James A. Edmonds; Joshua Lurz; Steven J. Smith; Marshall A. Wise

2006-01-01

39

The objECTS Framework for integrated Assessment: Hybrid Modeling of Transportation  

Microsoft Academic Search

Technology is a central issue for the global climate change problem, requiring analysis tools that can examine the impact of specific technologies within a long-term, global context. This paper describes the architecture of the ObjECTS-MiniCAM integrated assessment model, which implements a long-term, global model of energy, economy, agriculture, land-use, atmosphere, and climate change in a framework that allows the flexible

2006-01-01

40

Resuming electroconvulsive therapy (ECT) after emergence of asymptomatic atrial fibrillation during a course of right unilateral ECT.  

PubMed

Atrial fibrillation induced by electroconvulsive therapy (ECT) is rare, with only 3 reported cases. None of those cases involved either young healthy patients or right unilateral ECT. We report a 46-year-old healthy male observed to be in atrial fibrillation immediately after electrical induction of the 25th administration of right unilateral ECT. Diltiazem was administered, and he spontaneously cardioverted. After a negative cardiology workup, he safely resumed ECT. Atrial fibrillation was most likely triggered by autonomic imbalance due to the combination of electrical induction, seizure, and medication. PMID:22343588

Loeffler, George; Capobianco, Marc

2012-03-01

41

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

42

Ion Implant Technology for Intermediate Band Solar Cells  

NASA Astrophysics Data System (ADS)

This chapter describes the creation of an Intermediate Band (IB) on single crystal silicon substrates by means of high-dose Ti implantation and subsequent Pulsed Laser Melting (PLM). The Ti concentration over the Mott limit is confirmed by Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) measurements and the recovery of the crystallinity after annealing by means of Glancing Incidence X Ray Diffraction (GIXRD) and Transmission Electron Microscopy (TEM). Rutherford Backscattering Spectroscopy (RBS) measurements show that most of the atoms are located interstitially. Analysis of the sheet resistance and mobility measured using the van der Pauw geometry shows a temperature-dependent decoupling between the implanted layer and the substrate. This decoupling and the high laminated conductivity of the implanted layer could not be explained except if we assume that an IB has been formed in the semiconductor. A specific model for the bilayer electrical behaviour has been developed. The fitting of this model and also the simulation of the sheet resistance with the ATLAS code allow to determine that the IB energetic position is located around 0.36-0.38 eV below the conduction band. Carriers at the IB have a density very similar to the Ti concentration and behave as holes with mobilities as low as 0.4 cm2 Vs- 1.

Olea, Javier; Pastor, David; Luque, María Toledano; Mártil, Ignacio; Díaz, Germán González

43

GaAs FET Device Fabrication and Ion Implantation Technology (Microwave III-V Compound Semiconductors).  

National Technical Information Service (NTIS)

Microwave Schottky barrier FETs and ion implantation have been selected to provide a bench mark technology for evaluation of III-V compound semiconductor materials grown at NRL and elsewhere. FETs used here employ a nominal one micron gate length and are ...

K. J. Sleger H. B. Dietrich

1979-01-01

44

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.

2013-01-01

45

Accuracy of a digital impression system based on parallel confocal laser technology for implants with consideration of operator experience and implant angulation and depth.  

PubMed

Purpose: To evaluate the accuracy of a digital impression system based on parallel confocal red laser technology, taking into consideration clinical parameters such as operator experience and angulation and depth of implants. Materials and Methods: A maxillary master model with six implants (located bilaterally in the second molar, second premolar, and lateral incisor positions) was fitted with six polyether ether ketone scan bodies. One second premolar implant was placed with 30 degrees of mesial angulation; the opposite implant was positioned with 30 degrees of distal angulation. The lateral incisor implants were placed 2 or 4 mm subgingivally. Two experienced and two inexperienced operators performed intraoral scanning. Five different interimplant distances were then measured. The files obtained from the scans were imported with reverse-engineering software. Measurements were then made with a coordinate measurement machine, with values from the master model used as reference values. The deviations from the actual values were then calculated. The differences between experienced and inexperienced operators and the effects of different implant angulations and depths were compared statistically. Results: Overall, operator 3 obtained significantly less accurate results. The angulated implants did not significantly influence accuracy compared to the parallel implants. Differences were found in the amount of error in the different quadrants. The second scanned quadrant had significantly worse results than the first scanned quadrant. Impressions of the implants placed at the tissue level were less accurate than implants placed 2 and 4 mm subgingivally. Conclusions: The operator affected the accuracy of measurements, but the performance of the operator was not necessarily dependent on experience. Angulated implants did not decrease the accuracy of the digital impression system tested. The scanned distance affected the predictability of the accuracy of the scanner, and the error increased with the increased length of the scanned section. PMID:25032765

Giménez, Beatriz; Ozcan, Mutlu; Martínez-Rus, Francisco; Pradíes, Guillermo

2014-01-01

46

The Radiation Belt Storm Probes (RBSP) Energetic Particle, Composition, and Thermal Plasma (ECT) Instrument Suite  

Microsoft Academic Search

The Energetic particle, Composition, and Thermal plasma (ECT) instrument suite was selected recently by NASA as part of the Radiation Belt Storm Probe (RBSP) mission. In this presentation, we summarize the RBSP-ECT science investigation. The ECT suite contains a well-proven complement of particle instruments to ensure the highest quality measurements in the inner magnetosphere. The coordinated ECT particle measurements, analyzed

H. E. Spence; E. Kepko; G. Reeves; H. Funsten; M. Thomsen; M. Henderson; R. Friedl; R. Skoug; V. Jordanova; J. Fennell; J. B. Blake; J. Clemmons; T. O'Brien; J. Green; T. Onsager; S. Elkington; D. Baker; X. Li; J. Goldstein; D. Young; J. Jahn; R. Thorne; M. Hudson; R. Horne; S. Bourdarie; I. Mann

2006-01-01

47

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

48

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

49

History of some early developments in ion-implantation technology leading to silicon transistor manufacturing  

Microsoft Academic Search

Ion implantation of dopant impurities to form p-n junctions and other doped regions in silicon transistors has evolved from an experimental curiosity in solid-state physics to become a dominant technology in today's integrated circuit manufacturing. This paper traces the key inventions and early developments in ion beam doping concepts from the early 1950's through the 1970's as they were applied

RICHARD B. FAIR

1998-01-01

50

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

51

Development of vacuum arc ion sources for heavy ion accelerator injectors and ion implantation technology (invited)  

NASA Astrophysics Data System (ADS)

The status of experimental research and ongoing development and upgrade of MEVVA-type ion sources over the last two years since the previous ICIS-95 is reviewed. There are two main application fields for this ion source: heavy ion accelerators and material surface implantation technology. For particle accelerator ion injection to accelerators it is important to enhance the fractions of multiply charged ions in the ion beam as well as controlling the charge state distribution, and to improve of beam current stability (i.e., to minimize the beam noise) and pulse-to-pulse reproducibility. For ion implantation application we need to increase both the implantation dose rate and the source lifetime (between required maintenance downtime) as well as making this kind of source more reliable and of yet low cost. Most of experimental results reported on here have been obtained in a collaborative program between research groups LBNL (Berkeley, USA), GSI (Darmstadt, Germany), HCEI (Tomsk, Russia), and other important contributions have been made by the groups at (BNU, Beijing, China), EDU (Izmir, Turkey), and elsewhere.

Oks, Efim M.

1998-02-01

52

A programmed release multi-drug implant fabricated by three-dimensional printing technology for bone tuberculosis therapy  

Microsoft Academic Search

In the world, bone tuberculosis is still very difficult to treat and presents a challenge to clinicians. In this study, we utilized 3D printing technology to fabricate a programmed release multi-drug implant for bone tuberculosis therapy. The construction of the drug implant was a multi-layered concentric cylinder divided into four layers from the center to the periphery. Isoniazid and rifampicin

Weigang Wu; Qixin Zheng; Xiaodong Guo; Jianhua Sun; Yudong Liu

2009-01-01

53

The correlation of the indentation size e(ect measured with indenters of various shapes  

Microsoft Academic Search

Experimental results are presented which show that the indentation size e(ect for pyramidal and spherical indenters can be correlated.For a pyramidal indenter, the hardness measured in crystalline materials usually increases with decreasing depth of penetration, which is known as the indentation size e(ect.Spherical indentation also shows an indentation size e(ect.However, for a spherical indenter, hardness is not a(ected by depth,

J. G. Swadener; E. P. Georgea; G. M. Pharr

54

The ObjECTS: Framework for Integrated Assessment: Hybrid Modeling of Transportation  

SciTech Connect

Technology is a central issue for the global climate change problem, requiring analysis tools that can examine the impact of specific technologies with a long-term, global context. This paper describes the architecture of the ObjECTS-MiniCAM integrated assessment model, which implements a long-term, global model of energy, economy, agriculture, land-use, atmosphere, and climate change in a framework that allows the flexible incorporation of explicit technology detail. We describe the implementation of a ''bottom-up'' representation of the transportation sector as an illustration of this approach, in which the resulting hybrid model is fully integrated, internally consistent and theoretically compatible with the regional and global modeling framework. The analysis of the transportation sector presented here supports and clarifies the need for a comprehensive strategy promoting advanced vehicle technologies and an economy-wide carbon policy to cost-effectively reduce carbon emissions from the transportation sector in the long-term.

Kim, Son H.; Edmonds, James A.; Lurz, Joshua; Smith, Steven J.; Wise, Marshall A.

2006-09-01

55

Comparison of SAGS I vs. SAGS II delivery systems in emerging implantation technologies  

NASA Astrophysics Data System (ADS)

The International Fire Code has classified Subatmospheric Gas Delivery Systems (SAGS) technologies into two main categories: SAGS Type I and SAGS Type II systems. SAGS Type I delivery systems both store and deliver gases at subatmospheric pressures. An example of this technology is ATMI's Safe Delivery Source (SDS®) adsorbent based cylinder. SAGS Type II delivery systems store fluids at high pressure and utilize mechanical devices internal to the cylinder to deliver the gas at subatmospheric pressures. Typical mechanical devices used to enable subatmospheric delivery are either set point regulators or mechanical capillary based systems. This paper focuses on how these delivery systems perform against the unique requirements of traditional beam line ion implantation as well as solar and flat panel applications. Specifically, data are provided showing the capability of these systems with respect to flow rate, residual gas left within the cylinder, and cylinder end-point flow and delivery pressure dynamics.

Despres, Joseph; Sweeney, Joseph

2012-11-01

56

Bypassing the learning curve in permanent seed implants using state-of-the-art technology  

SciTech Connect

Purpose: The aim of this study was to demonstrate, based on clinical postplan dose distributions, that technology can be used efficiently to eliminate the learning curve associated with permanent seed implant planning and delivery. Methods and Materials: Dose distributions evaluated 30 days after the implant of the initial 22 consecutive patients treated with permanent seed implants at two institutions were studied. Institution 1 (I1) consisted of a new team, whereas institution 2 (I2) had performed more than 740 preplanned implantations over a 9-year period before the study. Both teams had adopted similar integrated systems based on three-dimensional (3D) transrectal ultrasonography, intraoperative dosimetry, and an automated seed delivery and needle retraction system (FIRST, Nucletron). Procedure time and dose volume histogram parameters such as D90, V100, V150, V200, and others were collected in the operating room and at 30 days postplan. Results: The average target coverage from the intraoperative plan (V100) was 99.4% for I1 and 99.9% for I2. D90, V150, and V200 were 191.4 Gy (196.3 Gy), 75.3% (73.0%), and 37.5% (34.1%) for I1 (I2) respectively. None of these parameters shows a significant difference between institutions. The postplan D90 was 151.2 Gy for I1 and 167.3 Gy for I2, well above the 140 Gy from the Stock et al. analysis, taking into account differences at planning, results in a p value of 0.0676. The procedure time required on average 174.4 min for I1 and 89 min for I2. The time was found to decrease with the increasing number of patients. Conclusion: State-of-the-art technology enables a new brachytherapy team to obtain excellent postplan dose distributions, similar to those achieved by an experienced team with proven long-term clinical results. The cost for bypassing the usual dosimetry learning curve is time, with increasing team experience resulting in shorter treatment times.

Beaulieu, Luc [Departement de Radio-oncologie, Centre Hospitalier Universitaire de Quebec, Hotel-Dieu de Quebec, Quebec, PQ (Canada)]. E-mail: beaulieu@phy.ulaval.ca; Evans, Dee-Ann Radford [Departments of Radiation Oncology and Medical Physics, Tom Baker Cancer Centre, Calgary, AB (Canada); Aubin, Sylviane [Departement de Radio-oncologie, Centre Hospitalier Universitaire de Quebec, Hotel-Dieu de Quebec, Quebec, PQ (Canada); Angyalfi, Steven [Departments of Radiation Oncology and Medical Physics, Tom Baker Cancer Centre, Calgary, AB (Canada); Husain, Siraj [Departments of Radiation Oncology and Medical Physics, Tom Baker Cancer Centre, Calgary, AB (Canada); Kay, Ian [Departments of Radiation Oncology and Medical Physics, Tom Baker Cancer Centre, Calgary, AB (Canada); Martin, Andre-Guy [Departement de Radio-oncologie, Centre Hospitalier Universitaire de Quebec, Hotel-Dieu de Quebec, Quebec, PQ (Canada); Varfalvy, Nicolas [Departement de Radio-oncologie, Centre Hospitalier Universitaire de Quebec, Hotel-Dieu de Quebec, Quebec, PQ (Canada); Vigneault, Eric [Departement de Radio-oncologie, Centre Hospitalier Universitaire de Quebec, Hotel-Dieu de Quebec, Quebec, PQ (Canada); Dunscombe, Peter [Departments of Radiation Oncology and Medical Physics, Tom Baker Cancer Centre, Calgary, AB (Canada)

2007-01-01

57

The Role of Ect2 Nuclear RhoGEF Activity in Ovarian Cancer Cell Transformation.  

PubMed

Ect2, a Rho guanine nucleotide exchange factor (RhoGEF), is atypical among RhoGEFs in its predominantly nuclear localization in interphase cells. One current model suggests that Ect2 mislocalization drives cellular transformation by promoting aberrant activation of cytoplasmic Rho family GTPase substrates. However, in ovarian cancers, where Ect2 is both amplified and overexpressed at the mRNA level, we observed that the protein is highly expressed and predominantly nuclear and that nuclear but not cytoplasmic Ect2 increases with advanced disease. Knockdown of Ect2 in ovarian cancer cell lines impaired their anchorage-independent growth without affecting their growth on plastic. Restoration of Ect2 expression rescued the anchorage-independent growth defect, but not if either the DH catalytic domain or the nuclear localization sequences of Ect2 were mutated. These results suggested a novel mechanism whereby Ect2 could drive transformation in ovarian cancer cells by acting as a RhoGEF specifically within the nucleus. Interestingly, Ect2 had an intrinsically distinct GTPase specificity profile in the nucleus versus the cytoplasm. Nuclear Ect2 bound preferentially to Rac1, while cytoplasmic Ect2 bound to RhoA but not Rac. Consistent with nuclear activation of endogenous Rac, Ect2 overexpression was sufficient to recruit Rac effectors to the nucleus, a process that required a functional Ect2 catalytic domain. Furthermore, expression of active nuclearly targeted Rac1 rescued the defect in transformed growth caused by Ect2 knockdown. Our work suggests a novel mechanism of Ect2-driven transformation, identifies subcellular localization as a regulator of GEF specificity, and implicates activation of nuclear Rac1 in cellular transformation. PMID:24386507

Huff, Lauren P; Decristo, Molly J; Trembath, Dimitri; Kuan, Pei Fen; Yim, Margaret; Liu, Jinsong; Cook, Danielle R; Miller, C Ryan; Der, Channing J; Cox, Adrienne D

2013-11-01

58

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

59

The Cresco Bridge and implant concept: presentation of a technology for fabrication of abutment-free, passively fitting superstructures.  

PubMed

This article describes a new and cost-effective concept comprising innovative and simplified clinical and laboratory procedures for the rational fabrication of abutment-free, cast-titanium superstructures with passive fit to implants. Other alloys, such as precious metal or cobalt-chromium, can also be used. The precision of fit between the implants and superstructure is obtained by the Cresco Ti Precision method. This method is a user-friendly technology and can be adapted to most implant systems on the market. The method does not include any abutments, even when implants are positioned in extremely different angulations or inclined in a facial or palatal direction. Coupled with a simple All Parts Included (API) delivery system, the concept therefore represents an efficient treatment alternative. PMID:15736782

Helldén, Leif B; Ericson, Gunnel; Olsson, Carl-Olof

2005-02-01

60

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

61

A source\\/drain formation technology utilizing sub-10 keV arsenic and assist-phosphorus implantation for 0.13 ?m MOSFET  

Microsoft Academic Search

We have developed a novel technology for formation of source\\/drain regions in 0.13 ?m MOSFETs. A combination of low-energy arsenic (8 keV) implantation and assist-phosphorous implantation suppresses transient enchanted diffusion (TED) of boron, and this improves Ion -Ioff characteristics as well as Vth roll-off. Assisted by low-dose phosphorous implantation, this technology can minimize both junction-leakage current and gate-poly depletion. An

K. Imai; S. Shishiguchi; K. Yamaguchi; N. Kimizuka; H. Onishi; T. Horiuchi

1999-01-01

62

Multiple gate oxide technology using nitrogen implantation and high-pressure O2 oxidation  

NASA Astrophysics Data System (ADS)

We demonstrate a novel process for multiple gate oxide technology using a combination of nitrogen implantation and high-pressure O2 oxidation. Using this approach we realize a range of different thicknesses from 26 to 140 Å simultaneously on a silicon wafer. A secondary ion mass spectroscopy profile shows an identical nitrogen peak that cannot be obtained by conventional oxynitridation. A vertical high-pressure (VHP) O2 device shows a leakage current about ten times lower and only ~40 mV difference in VFB compared to the SiO2 device when the nitrogen dose is 7 × 1014 atoms cm-2. The elimination of boron penetration is observed after a drive-in of 1050 °C for 30 s. In this work, we demonstrate a novel approach to realize >500% difference in the oxide growth rate using VHP oxidation (15-25 atm at 750-850 °C) and N implantation (between 1 × 1014 and 3 × 1015 atoms cm-2).

Lee, C. H.; Kwong, D. L.

2003-02-01

63

Ironic technology: Old age and the implantable cardioverter defibrillator in US health care.  

PubMed

We take the example of cardiac devices, specifically the implantable cardioverter defibrillator, or ICD, to explore the complex cultural role of technology in medicine today. We focus on persons age 80 and above, for whom ICD use is growing in the U.S. We highlight an ironic feature of this device. While it postpones death and 'saves' life by thwarting a lethal heart rhythm, it also prolongs living in a state of dying from heart failure. In that regard the ICD is simultaneously a technology of life extension and dying. We explore that irony among the oldest age group -- those whose considerations of medical interventions are framed by changing societal assumptions of what constitutes premature death, the appropriate time for death and medicine's goals in an aging society. Background to the rapidly growing use of this device among the elderly is the 'technological imperative' in medicine, bolstered today by the value given to evidence-based studies. We show how evidence contributes to standards of care and to the expansion of Medicare reimbursement criteria. Together, those factors shape the ethical necessity of physicians offering and patients accepting the ICD in late life. Two ethnographic examples document the ways in which those factors are lived in treatment discussions and in expectations about death and longevity. PMID:21126815

Kaufman, Sharon R; Mueller, Paul S; Ottenberg, Abigale L; Koenig, Barbara A

2011-01-01

64

Health Technology Assessment Reports, 1990. Number 10. Implantation of the Automatic Cardioverter-Defibrillator.  

National Technical Information Service (NTIS)

The automatic implantable cardioverter-defibrillator (AICD) is an electronic device that can be implanted in patients identified as being at high risk for sudden cardiac death (SDC) due to ventricular tachycardia or fibrillation (VT/VF). The device contin...

H. Handelsman

1991-01-01

65

[Modern digital technologies as a useful tool for dental implantation planning].  

PubMed

The method of implant size choice concerning mechanical properties of bone tissue surrounding an implant is proposed based on CT-assessment of anatomical and topographical conditions using MIMICS-ANSYS software. PMID:23752851

Chu?ko, A N; Levandovski?, R A; Ugrin, M M; Belikov, A B

2013-01-01

66

Electroconvulsive Therapy in Patients With Skull Defects or Metallic Implants: A Review of the Literature and Case Report  

PubMed Central

Context: Head injury is often associated with psychiatric morbidity. While it is well understood that the loss of critical areas of the brain may play a role in cognitive dysfunction and change in personality, head injury can also have profound effects on mood and cognition. The role of medications in the treatment of mood disorders associated with brain injury is well documented, and there is also evidence favoring the use of electroconvulsive therapy (ECT) in this context. However, data are limited on the use of ECT in patients with skull defects or metallic head implants. Evidence Acquisition: First, a review of the literature on use of ECT in patients with metallic head implants is provided. Electronic databases and online sites, including PubMed, Cochrane Library of Systematic Reviews, and UpToDate, were used to search for relevant articles and case reports on the use of ECT in patients with and without metallic implants in the head (1964 to 2009). The search terms electroconvulsive, electroconvulsive therapy, ECT, electroshock therapy, EST, head injury, brain injury, metallic plates, metallic implants, skull prosthesis, and depression were used interchangeably. The search produced 7 articles discussing exclusively the use of ECT in patients with a metallic skull plate. Second, the case of the successful and safe use of ECT in an individual with a previous history of brain trauma and metallic plate implantation is described. Results: Most cases of head injury are managed by neurologists and rehabilitation consultants; the more severe cases of depression and other mood disorders tend to be referred for specialist psychiatric care. With greater degrees of deficit following head injury, management becomes more complicated. Our patient showed positive results with ECT, including improvement in depressive features and resolution of suicidal ideas/plans. Conclusion: ECT is an effective and safe alternative in patients with a history of brain trauma and metallic plate implantation who subsequently develop treatment-resistant depression and associated suicidal ideas or plans refractory to management with medications.

Delva, Nicholas; McRae, Harold; Campbell, Laura A.; Cole, Julie

2012-01-01

67

Low-cost ion implantation and annealing technology for solar cells  

NASA Technical Reports Server (NTRS)

Ion implantation and thermal annealing techniques for processing junctions and back surface layers in solar cells are discussed. Standard 10 keV (31)p(+) junction implants and 25 keV (11)B(+) back surface implants in combination with three-step furnace annealing are used for processing a range of silicon materials and device structures. Cells with efficiencies up to 16.5% AM1 are being produced, and large-area terrestrial cells with implanted junctions and back fields being fabricated in pilot production exhibit average efficiencies in excess of 15% AM1. Thermal annealing methods for removal of the radiation damage caused by implantation should be replaced by transient processing techniques in future production. Design studies have been completed for solar cell processing implanters to support 10 MW/yr and 100 MW/yr production lines, and analyses indicate that implantation costs can be reduced to approximately 1 cent/watt.

Kirkpatrick, A. H.; Minnucci, J. A.; Greenwald, A. C.

1980-01-01

68

Implantable Microimagers  

PubMed Central

Implantable devices such as cardiac pacemakers, drug-delivery systems, and defibrillators have had a tremendous impact on the quality of live for many disabled people. To date, many devices have been developed for implantation into various parts of the human body. In this paper, we focus on devices implanted in the head. In particular, we describe the technologies necessary to create implantable microimagers. Design, fabrication, and implementation issues are discussed vis-à-vis two examples of implantable microimagers; the retinal prosthesis and in vivo neuro-microimager. Testing of these devices in animals verify the use of the microimagers in the implanted state. We believe that further advancement of these devices will lead to the development of a new method for medical and scientific applications.

Ng, David C.; Tokuda, Takashi; Shiosaka, Sadao; Tano, Yasuo; Ohta, Jun

2008-01-01

69

Role of EctR as transcriptional regulator of ectoine biosynthesis genes in Methylophaga thalassica.  

PubMed

In the halophilic aerobic methylotrophic bacterium Methylophaga thalassica, the genes encoding the enzymes for biosynthesis of the osmoprotectant ectoine were shown to be located in operon ectABC-ask. Transcription of the ect-operon was started from the two promoters homologous to the ?(70)-dependent promoter of Escherichia coli and regulated by protein EctR, whose encoding gene, ectR, is transcribed from three promoters. Genes homologous to ectR of methylotrophs were found in clusters of ectoine biosynthesis genes in some non-methylotrophic halophilic bacteria. EctR proteins of methylotrophic and heterotrophic halophiles belong to the MarR-family of transcriptional regulators but form a separate branch on the phylogenetic tree of the MarR proteins. PMID:22860907

Mustakhimov, I I; Reshetnikov, A S; Fedorov, D N; Khmelenina, V N; Trotsenko, Y A

2012-08-01

70

Detection and Sizing of Defects in Structural Components of a Nuclear Power Plant by ECT  

NASA Astrophysics Data System (ADS)

In this paper, progress of ECT technique for inspection of stress corrosion cracks in a structural component of a nuclear power plant is reported. Access and scanning vehicle (robot), advanced probes for SG tube inspection, development and evaluation of new probes for welding joint, and ECT based crack sizing technique are described respectively. Based on these new techniques, it is clarified that ECT can play as a supplement of UT for the welding zone inspection. It is also proved in this work that new ECT sensors are efficient even for a stainless plate as thick as 15mm.

Chen, Zhenmao; Miya, Kenzo

2005-04-01

71

High Energy Ion Implantation for C-MOS Isolation N-Wells Technology: Some Problems Related to the Use of Multicharged Phosphorous Ions in an Industrial Context.  

National Technical Information Service (NTIS)

It has been shown that high energy ion implantation can be a very attractive technique for the realisation of isolation wells in C-MOS technology. This technique needs high energy ion implantation equipment which is still rare and expensive, so the use of...

P. Spinelli J. Escaron A. Soubie M. Bruel

1984-01-01

72

Advances in pump technology: insulin patch pumps, combined pumps and glucose sensors, and implanted pumps.  

PubMed

This review discusses the most recent developments in insulin pump technology. The benefits of the insulin pump to patients with type 1 diabetes are recognized both for its metabolic effectiveness and its positive effects on quality of life. The current pumps are reliable, small and light, and are becoming more and more sophisticated. Nevertheless, there remain practical and psychological constraints for the patient. However, recent patch-pump advances should simplify the technical aspects of pump treatment and enhance patient comfort. Another advance combines the insulin pump with a glucose sensor. Such a combination is logical for optimizing pump use and, to that end, developing an automated or 'closed-loop'system that permits the delivery of subcutaneous insulin adjusted according to measured levels of subcutaneous glucose. Finally, implanted insulin pumps have proven their worth not only because of their simple use, but also for their contribution in the artificial pancreas project. Indeed, the prompt response with intraperitoneal administration of insulin makes it of interest for use in a closed-loop system. PMID:22208717

Schaepelynck, P; Darmon, P; Molines, L; Jannot-Lamotte, M F; Treglia, C; Raccah, D

2011-12-01

73

On new reproductive technologies and family ethics: Pre-implantation genetic diagnosis for sibling donor in Israel and Germany  

Microsoft Academic Search

This paper discusses the policy debate and ethical discussion surrounding pre-implantation genetic diagnosis (PGD) for sibling donor (SD) in Germany and Israel. Based on an analysis of the regulations and ethical discourse concerning a unique form of new reproductive technology (NRT)—PGD for SD—we complement the scholarly discussion of NRTs in these countries, by pointing to an explanatory factor that has

Yael Hashiloni-Dolev; Shiri Shkedi

2007-01-01

74

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

PubMed

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. PMID:24429673

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

75

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

76

Implant planning and placement using optical scanning and cone beam CT technology.  

PubMed

There is a growing interest in minimally invasive implant therapy as a standard prosthodontic treatment, providing complete restoration of occlusal function. A new treatment method (CADDIMA), which combines both computerized tomographic (CT) and optical laser-scan data for planning and design of surgical guides, implant abutments, and prosthetic devices, is described. Imaging using a "NewTom 3G" cone beam CT scanner and a modified laser triangulation scanner "D200c" is discussed, as are impression and surgical guide fabrication, which allow for flapless, precise implant placement and an accurate provisional prosthesis. The new approach gives the operator full control over the design of the implant prosthesis for planning of proper occlusal relations and shows promise for further evaluation. PMID:18482361

van der Zel, Jef M

2008-08-01

77

High-dose carbon implantations into silicon: fundamental studies for new technological tricks  

Microsoft Academic Search

Depending on the implantation temperature, the implantation of carbon ions into silicon at high doses results in the formation of either amorphous SiCx or crystalline 3C-SiC precipitates. Various aspects of the precipitation behaviour observed, such as the impeded nucleation, the limited growth and the resulting sensitivity to ballistic destruction are attributed to the large interfacial energy between crystalline silicon and

J. K. N. Lindner

2003-01-01

78

High-dose carbon implantations into silicon: fundamental studies for new technological tricks  

Microsoft Academic Search

.   Depending on the implantation temperature, the implantation of carbon ions into silicon at high doses results in the formation\\u000a of either amorphous SiCx or crystalline 3C-SiC precipitates. Various aspects of the precipitation behaviour observed, such as the impeded nucleation,\\u000a the limited growth and the resulting sensitivity to ballistic destruction are attributed to the large interfacial energy between\\u000a crystalline silicon

J. K. N. Lindner

2003-01-01

79

Battery and capacitor technology for uniform charge time in implantable cardioverter-defibrillators  

Microsoft Academic Search

Implantable cardioverter-defibrillators (ICDs) are implantable medical devices designed to treat ventricular fibrillation by administering a high-voltage shock directly to the heart. Minimizing the time a patient remains in fibrillation is an important goal of this therapy. Both batteries and high-voltage capacitors used in these devices can display time-dependency in performance, resulting in significant extension of charge time. Altering the electrode

Paul M. Skarstad

2004-01-01

80

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.

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

2012-01-01

81

Attitudes toward technology and risk: Going beyond what is immediately given1  

Microsoft Academic Search

In this paper, perceived risk and attitudes toward technology are considered in a wide contextual perspective. Risk perception data are related to technology and technology attributes, in particular with respect to the possibility of replacinga technology, to the belief that it may have as yet unknown e¡ects, and have e¡ects involvinga destructive relationship with Nature. These contextual characteristics of a

82

Income E¤ects and Indeterminacy in a Calibrated One-Sector Growth Model  

Microsoft Academic Search

Abstract This paper analyzes how,the indeterminacy,of competitive,equilibrium,in one-sector growth models,depends,on the magnitude,of the households’income e¤ect on the demand,for leisure. The paper,…rst establishes that the presence of income,e¤ect is necessary for the existence of an indeterminate,equilibrium. Because I am,further interested in quantitatively characterizing regions of uniqueness,and,regions of indeterminacy,of equilibria as a function of this income e¤ect, I need a utility function

Nir Jaimovich

83

The use of laser technology (Er;Cr:YSGG) and stereolithography to aid in the placement of a subperiosteal implant: case study.  

PubMed

The use of laser technology has helped this clinician to provide treatment with less postoperative pain and increased healing. The subperiosteal implant is a modality that has been used for several decades, although its popularity has declined in favor of endosseous dental implants. In some instances, however, it remains the treatment of choice, specifically in the atrophic mandible (where placement of endosseous implants is not possible) or when placement would increase the chances of jaw fracture. This article reports the case of a patient rehabilitated using a simplified surgical protocol involving laser surgery and stereolithography. PMID:19288882

Kusek, Edward R

2009-01-01

84

The controlled-releasing drug implant based on the three dimensional printing technology: Fabrication and properties of drug releasing in vivo  

Microsoft Academic Search

Three dimensional (3D) printing technology was utilized to fabricate a new type of drug implant with complicated architectures,\\u000a employing levofloxacin (LVFX) and rifampicine (RFP) as model drugs. The prepared drug implant prototype consists of a double-layer\\u000a structure, of which the upper region is a reservoir system containing RFP and the lower region is a matrix one containing\\u000a LVFX. The release

Weigang Wu; Qixin Zheng; Xiaodong Guo; Weidong Huang

2009-01-01

85

Materials processing towards development of rapid prototyping technology for manufacturing biomedical implants  

Microsoft Academic Search

Materials processing towards development of fused deposition of materials (FDM) method for manufacturing biomedical implants has been studied experimentally. Main processing steps consisted of thermoplastic binder development in the ethylene vinyl acetate (EVA)-microcrystalline wax system, feedstock extrusion, characterization and optimization of binder degradation, and sintering of calcium deficient hydroxyapatite. Differential scanning calorimetry (DSC) revealed that the melting index (MI) of

Senol Pekin

2000-01-01

86

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.

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

2003-01-01

87

The Effect of Technology and Testing Environment on Speech Perception Using Telehealth with Cochlear Implant Recipients  

ERIC Educational Resources Information Center

Purpose: In this study, the authors evaluated the effect of remote system and acoustic environment on speech perception via telehealth with cochlear implant recipients. Method: Speech perception was measured in quiet and in noise. Systems evaluated were Polycom visual concert (PVC) and a hybrid presentation system (HPS). Each system was evaluated…

Goehring, Jenny L.; Hughes, Michelle L.; Baudhuin, Jacquelyn L.; Valente, Daniel L.; McCreery, Ryan W.; Diaz, Gina R.; Sanford, Todd; Harpster, Roger

2012-01-01

88

Advanta facial implants.  

PubMed

Advanta facial implants represent a new method of expanded polytetrafluoroethylene (ePTFE) technology and appear to be different from previous ePTFE products. The implants appear to work well when used for lip augmentation. The author has 18 months' experience with this implant. Placement of these implants is simple and predictable. The complication rate is low and the implants are serviceable. The procedure is reversible without extensive damage to normal tissue. The Advanta facial implant appears to be a useful option in the armamentarium of the cosmetic oral and maxillofacial surgeon. PMID:18088762

Niamtu, Joseph

2005-02-01

89

COMPARISON OF THERAPEUTIC EFFICACY OF ECT AND IMIPRAMINE : A RANDOMIZED CONTROLLED TRIAL  

PubMed Central

Efficacy studies comparing ECT and tricyclics in depression have had methodological limitations. This study compared EC T and imipramine (IMN) prescribed as the first line of treatment in major depression, Drug-naive, consenting, DSM-IV major depression patients (n=28), were randomized to receive either bilateral ECTs or IMN (225 mg/d) for four weeks. Severity of depression was scored at twice weekly intervals. Subjective side effects were scored at second and fourth week. Patients had significant reductions in depression scores over time but there were no differences between the two treatment groups. The rate of antidepressant response did not significantly differ between the two groups. ECT group had significantly fewer side effects. IMN offered therapeutic response comparable to ECT without compromising on the speed of antidepressant response, but caused more side effects.

Selvan, C. Panneer; Mayur, Prashanth M.; Gangadhar, B.N.; Janakiramaiah, N.; Subbakrishna, D.K.; Murali, N.

1999-01-01

90

What does the electroencephalogram tell us about the mechanisms of action of ECT in major depressive disorders?  

PubMed

Electroconvulsive therapy (ECT) remains to be one of the most effective treatment options in treatment-resistant major depressive disorder (MDD). From the early days, researchers have embarked on extracting information from electroencephalography (EEG) recordings before, during, and after ECT to identify neurophysiological targets of ECT and discover EEG predictors of response to ECT in patients with MDD. In this article, we provide an overview of visually detected and quantitative EEG features that could help in furthering our understanding of the mechanisms of action of ECT in MDD. We further discuss the EEG findings in the context of postulated hypotheses of ECT therapeutic pathways. We introduce an alternative and unifying hypothesis suggesting that ECT may exert its therapeutic efficacy through resetting the aberrant functional connectivity and promoting the generation of new and healthy connections in brain regions implicated in MDD pathophysiology, a mechanism that may be in part mediated by the ECT-induced activation of inhibitory and neuroplasticity mechanisms. We further discuss the added value of EEG markers in the larger context of ECT research and as complementary to neuroimaging and genetic markers. We conclude by drawing attention to the need for longitudinal studies in large cohort of patients and the need for standardization and validation of EEG algorithms of functional connectivity across studies to facilitate the translation of EEG correlates of ECT response in routine clinical practice. PMID:24810774

Farzan, Faranak; Boutros, Nash N; Blumberger, Daniel M; Daskalakis, Zafiris J

2014-06-01

91

Cochlear Implants  

MedlinePLUS

... treated only with a cochlear implant. How do cochlear implants work? Cochlear implants bypass damaged hair cells and ... brain, where it is interpreted as meaningful sound. Cochlear implant benefits Cochlear implants are designed only for individuals ...

92

Income and Pollutant Emissions in the ObjECTS MiniCAM Model  

SciTech Connect

This paper examines the implications of the relationship between income and pollutant emission controls as parameterized in the ObjECTS MiniCAM integrated assessment model. Future scenarios for energy-related emissions of nitrous oxide (NOx) and sulfur dioxide (SO2) are presented along with the methodology used to parameterize this relationship. We use a “pseudo-Kuznets” approach where the level of emission control is assumed to vary with per-capita income. No explicit assumption is, therefore, made about the relationship between income and emissions — emissions are the result of driving forces, such as economic activity level, and energy combustion technology in addition to emission controls. Emission projections depend both on the assumptions for when emissions controls are implemented and the stringency of those controls. We suggest that historical analysis of the relationship between income and emission controls might be particularly useful in informing the selection of parameters that control when emission controls are implemented. Historical analysis is likely to be less helpful in informing the selection of parameters for the future levels of control, however, particularly at future times when parameter values are well outside the range of historical experience.

Smith, Steven J.

2005-01-03

93

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.

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

2013-01-01

94

On new reproductive technologies and family ethics: pre-implantation genetic diagnosis for sibling donor in Israel and Germany.  

PubMed

This paper discusses the policy debate and ethical discussion surrounding pre-implantation genetic diagnosis (PGD) for sibling donor (SD) in Germany and Israel. Based on an analysis of the regulations and ethical discourse concerning a unique form of new reproductive technology (NRT)--PGD for SD--we complement the scholarly discussion of NRTs in these countries, by pointing to an explanatory factor that has been so far neglected, namely the hegemonic notions regarding the ideal relationship between the generations, and the mutual obligations between different family members in Germany and Israel. We argue the fact that PGD (in general) and PGD for SD (in particular) have been banned in Germany, but were endorsed without hesitation in Israel, has to do with different perceptions of family ethics within the two societies. Furthermore, we argue that this factor contributes significantly to the more general understanding of German and Israeli policies regarding NRTs. PMID:17669568

Hashiloni-Dolev, Yael; Shkedi, Shiri

2007-11-01

95

ects of super¢cial layers on coseismic displacements for a dip-slip fault and geophysical implications  

Microsoft Academic Search

SUMMARY We study the e¡ect of a super¢cial layer overlying a half-space on the surface displacements created by a dip-slip dislocation on aplanar rectangular fault using a 2-D ¢nite element model. The e¡ect of the density and Poisson's ratio is negligible. On the other hand, the contrast in Young's modulus between the top layer and the half-space below signi¢cantly a¡ects

R. Cattin; P. Briole; H. Lyon-Caen; P. Bernard; P. Pinettes

96

Assessment on Implantable Defibrillators and the Evidence for Primary Prevention of Sudden Cardiac Death. Technology Assessment Report.  

National Technical Information Service (NTIS)

Implantable cardioverterdefibrillators (ICDs) are battery-powered implantable devices that monitor heart rhythm and deliver therapy in the form of either electric shock or antitachycardia pacing (ATP) when a life-threatening ventricular arrhythmia is dete...

A. Earley A. C. Garlitski E. M. Balk K. Uhlig R. Persson

2013-01-01

97

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.

Payne, Nancy A.; Prudic, Joan

2010-01-01

98

Building Better Bones Researchers are advancing medical bone implant technology with rapid prototyping techniques and digitally designed zirconia molds  

Microsoft Academic Search

spects of rapid prototyping and ti- tanium casting have been com- bined in a system to produce tita- nium replicas of human bones. Although titanium is currently used for bone replacement, implants are simple geometric approximations of the bone shape. Mismatches between implants and real bone often cause stress con- centrations and result in premature implant failure. If more accurate

NICOLE HARLAN; REUBEN REYES; DAVID BOURELL

2000-01-01

99

A hybrid ECT image reconstruction based on Tikhonov regularization theory and SIRT algorithm  

NASA Astrophysics Data System (ADS)

Electrical Capacitance Tomography (ECT) image reconstruction is a key problem that is not well solved due to the influence of soft-field in the ECT system. In this paper, a new hybrid ECT image reconstruction algorithm is proposed by combining Tikhonov regularization theory and Simultaneous Reconstruction Technique (SIRT) algorithm. Tikhonov regularization theory is used to solve ill-posed image reconstruction problem to obtain a stable original reconstructed image in the region of the optimized solution aggregate. Then, SIRT algorithm is used to improve the quality of the final reconstructed image. In order to satisfy the industrial requirement of real-time computation, the proposed algorithm is further been modified to improve the calculation speed. Test results show that the quality of reconstructed image is better than that of the well-known Filter Linear Back Projection (FLBP) algorithm and the time consumption of the new algorithm is less than 0.1 second that satisfies the online requirements.

Lei, Wang; Xiaotong, Du; Xiaoyin, Shao

2007-07-01

100

Dental Implants  

MedlinePLUS

... 11.14 Read More Find a Cosmetic Dentist Teeth Whitening Accredited and General Member Dental Patients ? Cosmetic Procedures ? Dental Implants Dental Implants The ... key benefit of dental implants over other tooth replacement systems is that an implant connects directly ...

101

High current vacuum-arc ion source for ion implantation and coating deposition technologies  

SciTech Connect

This work is devoted to the development and investigation of a high current ion source based on dc vacuum-arc plasma generation. Extraction and acceleration of ion beams are realized in a repetitively pulsed mode with the pulse repetition rate up to 200 pps, the pulse duration up to 400 {mu}s, the accelerating voltage up to 40 kV, and the pulsed ion-beam current up to 2 A. To remove microparticles from the vacuum-arc plasma a straight-line plasma filter is used. Examples of the source use for realization of high-intensity and high-concentration ion implantation regimes including those with formation of doped layers at depths that exceed ion projective range for more than an order of magnitude are presented. At the expense of change in order and intensity of ion and plasma material treatment, the advantage of application of one source for execution of material surface pretreatment and activation regimes, formation of wide transition layers between the substrate and coating, coating deposition, and high-intensity ion mixing using ions of the same type was shown.

Ryabchikov, Alexander I.; Ryabchikov, Igor A.; Stepanov, Igor B.; Dektyarev, Sergey V. [Nuclear Physics Institute, Tomsk Polytechnic University, 2A Lenina Avenue, Tomsk 634050 (Russian Federation)

2006-03-15

102

High current vacuum-arc ion source for ion implantation and coating deposition technologies  

NASA Astrophysics Data System (ADS)

This work is devoted to the development and investigation of a high current ion source based on dc vacuum-arc plasma generation. Extraction and acceleration of ion beams are realized in a repetitively pulsed mode with the pulse repetition rate up to 200 pps, the pulse duration up to 400 ?s, the accelerating voltage up to 40 kV, and the pulsed ion-beam current up to 2 A. To remove microparticles from the vacuum-arc plasma a straight-line plasma filter is used. Examples of the source use for realization of high-intensity and high-concentration ion implantation regimes including those with formation of doped layers at depths that exceed ion projective range for more than an order of magnitude are presented. At the expense of change in order and intensity of ion and plasma material treatment, the advantage of application of one source for execution of material surface pretreatment and activation regimes, formation of wide transition layers between the substrate and coating, coating deposition, and high-intensity ion mixing using ions of the same type was shown.

Ryabchikov, Alexander I.; Ryabchikov, Igor A.; Stepanov, Igor B.; Dektyarev, Sergey V.

2006-03-01

103

Correcting for observed exposures in randomized experiments using random e®ects structural models and structural covariance models  

Microsoft Academic Search

Modern statistical methods for causal inference on the e®ects of observed exposures in randomized experiments model the shift in mean or distribution of responses following a physical change in exposure. We argue that insight in interventions and their causal e®ects can also benet from direct investigation of their impact on outcome variation. We develop 2 approaches for data structures which

S. Vansteelandt; E. Goetghebeur

104

Implant Chips  

NSDL National Science Digital Library

A group of eight people, including all members of one Florida family, had an implant chip, roughly the size of a grain of rice, injected under their skin on Friday, May 10. Manufactured by Applied Digital Solutions (ADS), the chips store a special identification number that enables the retrieval of personal and medical information. In the event of a medical emergency, a special handheld scanner activates the dormant digital implant, which provides identification data with which medical personnel can query ADS's database, the location of the patient's medical records. Alzheimer's patients seem to be the most promising market for this technology, even though other people, like the Florida family, hope to benefit from it as well. Another product that ADS offers is called Digital Angel, a wearable global positioning system (GPS) device that, among other things, can track in real time the wearer's physical movements. In the future, ADS is planning to release a product that will utilize both of these technologies: an implanted GPS-enabled chip. Unlike VeriChip, though, the GPS-enabled implant would require Food and Drug Administration (FDA) approval, meaning the US market won't see its introduction until after FDA testing. Many organizations, ranging from privacy advocates to religious groups, have already denounced VeriChip and its eventually successors, associated them with "Big Brother" and the biblical "Mark of the Beast."To read about the eight people that received their implants, look at the first and second sites, articles from the Los Angeles Times and Miami Herald respectively. For a non-US perspective, view the news story posted by the British Broadcasting Company (BBC). The fourth site, an extensive analysis of the subject from ABC News, should give readers a broader understanding of implanted chips and their potential uses. Two sites from ADS are next -- VeriChip's product pages and the press release that details a FDA's decision regarding VeriChip in April, 2002. Finally, the last two sites give more information on Digital Angel and a sample of GPS technology already in use.

Schroeder, Ted.

2002-01-01

105

First long term in vivo study on subdurally implanted micro-ECoG electrodes, manufactured with a novel laser technology.  

PubMed

A novel computer aided manufacturing (CAM) method for electrocorticography (ECoG) microelectrodes was developed to be able to manufacture small, high density microelectrode arrays based on laser-structuring medical grade silicone rubber and high purity platinum. With this manufacturing process, we plan to target clinical applications, such as presurgical epilepsy monitoring, functional imaging during cerebral tumor resections and brain-computer interface control in paralysed patients, in the near future. This paper describes the manufacturing, implantation and long-term behaviour of such an electrode array. In detail, we implanted 8-channel electrode arrays subdurally over rat cerebral cortex over a period of up to 25 weeks. Our primary objective was to ascertain the electrode's stability over time, and to analyse the host response in vivo. For this purpose, impedance measurements were carried out at regular intervals over the first 18 weeks of the implantation period. The impedances changed between day 4 and day 7 after implantation, and then remained stable until the end of the implantation period, in accordance with typical behaviour of chronically implanted microelectrodes. A post-mortem histological examination was made to assess the tissue reaction due to the implantation. A mild, chronically granulated inflammation was found in the area of the implant, which was essentially restricted to the leptomeninges. Overall, these findings suggest that the concept of the presented ECoG-electrodes is promising for use in long-term implantations. PMID:20838900

Henle, C; Raab, M; Cordeiro, J G; Doostkam, S; Schulze-Bonhage, A; Stieglitz, T; Rickert, J

2011-02-01

106

Phosphorus Fertilizer and Grazing Management Eff ects on Phosphorus in Runoff from Dairy Pastures  

Microsoft Academic Search

ects on runoff P concentration of P rate, P rate × number of applications (P < 0.001), P rate × time since fertilizer ( P < 0.001), dung P (P < 0.001), time since grazing ( P < 0.05), and pasture biomass (P < 0.001). A conceptual model of the sources of P in runoff comprising three components is proposed

Warwick J. Dougherty; Paul J. Nicholls; Paul J. Milham; J. Havilah; Roy A. Lawrie

107

ECT2 amplification and overexpression as a new prognostic biomarker for early-stage lung adenocarcinoma.  

PubMed

Genetic abnormality in early-stage lung adenocarcinoma was examined to search for new prognostic biomarkers. Six in situ lung adenocarcinomas and nine small but invasive adenocarcinomas were examined by array-comparative genomic hybridization, and candidate genes of interest were screened. To examine gene abnormalities, 83 cases of various types of lung carcinoma were examined by quantitative real-time genomic PCR and immunohistochemistry. The results were then verified using another set of early-stage adenocarcinomas. Array-comparative genomic hybridization indicated frequent amplification at chromosome 3q26. Of the seven genes located in this region, we focused on the epithelial cell transforming sequence 2 (ECT2) oncogene, as ECT2 amplification was detected only in invasive adenocarcinoma, and not in in situ carcinoma. Quantitative PCR and immunohistochemistry analyses also detected overexpression of ECT2 in invasive adenocarcinoma, and this was correlated with both the Ki-67 labeling index and mitotic index. In addition, it was associated with disease-free survival and overall survival of patients with lung adenocarcinoma. These results were verified using another set of early-stage adenocarcinomas resected at another hospital. Abnormality of the ECT2 gene occurs at a relatively early stage of lung adenocarcinogenesis and would be applicable as a new biomarker for prognostication of patients with lung adenocarcinoma. PMID:24484057

Murata, Yoshihiko; Minami, Yuko; Iwakawa, Reika; Yokota, Jun; Usui, Shingo; Tsuta, Koji; Shiraishi, Kouya; Sakashita, Shingo; Satomi, Kaishi; Iijima, Tatsuo; Noguchi, Masayuki

2014-04-01

108

Multichannel implantable telemetry system  

NASA Technical Reports Server (NTRS)

Multiplexed biotelemetry system for animal research combines several power-saving features. Implantable sensor measures up to eight parameters simultaneously, including blood flow. Microamp transistors, switching circuits, and CMOS technology are used to lower power requirements. However, when blood flow is monitored, these measures are insufficient to reduce power enough for long-term operation from implantable primary battery.

Fryer, T. B.; Mccutcheon, E. P.; Sandler, H.; Freund, W.

1977-01-01

109

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

110

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

111

Cochlear Implants (For Parents)  

MedlinePLUS

Sometimes called a "bionic ear," the cochlear implant offers the hope of regaining or restoring the ability to sense sound for some people ... does may help kids better understand their new bionic ear and the cool technology behind it that ...

112

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

113

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

114

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

115

Semiconductor Measurement Technology: Differential Capacity-Voltage Profiling of Schottky Barrier Diodes for Measuring Implanted Depth Distributions in Silicon.  

National Technical Information Service (NTIS)

This report discusses experimental and analytical aspects of differential capacitance-voltage profiling of ion-implanted carrier depth distributions using reverse-biased Schottky barrier diodes and the associated accuracies, experimental errors, and range...

R. G. Wilson D. M. Jamba

1982-01-01

116

Income and Pollutant Emissions in the ObjECTS MiniCAM Model  

Microsoft Academic Search

This article examines the relationship between income and pollutant emissions in the ObjECTS Mini Climate Assessment Model (MiniCAM) to determine how historical analysis can best guide modeling efforts. Future scenarios for energy-related emissions of nitrous oxide (NOx) and sulfur dioxide (SO2)are presented along with the methodology used. A pseudo-Kuznets approach is used where the level of emission control is assumed

Steven J. Smith; Steven J

2005-01-01

117

E!ects of prosodic and lexical constraints on parsing in young children (and adults) q  

Microsoft Academic Search

Prior studies of ambiguity resolution in young children have found that children rely heavily on lexical information but persistently fail to use referential constraints in online parsing (Trueswell, J.C., Sekerina, I., Hill, N.M., & Logrip, M.L, (1999). The kindergarten-path e!ect: Studying on-line sentence processing in young children. Cognition, 73, 89- 134; Snedeker, J. & Trueswell, J. (2004). The developing constraints

Jesse Snedeker; Sylvia Yuan

118

D Rf-Ect Simulations of Isi of U-Bend SG Tubes in Fbr  

NASA Astrophysics Data System (ADS)

The paper focus on 3-dimensional finite element simulations of the steam generator inspection using remote field eddy current testing (RF-ECT) in order to asses the performance of the in-service inspection in SG tubes. It is evaluated the influences of the SG tubes U-bend curvature on the eddy current sensor signal by taking into account a 3D model in which also multiple SG tubes are located close to each other, as in the nuclear reactor.

Mihalache, Ovidiu; Yamaguchi, Toshihiko; Ueda, Masashi; Tsukimori, Kazuyuki

2010-02-01

119

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

120

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

121

How does skilled emigration a¤ect developing countries? Facts theory and policy  

Microsoft Academic Search

Abstract This paper reviews what,is known,to date about the magnitude,of the brain drain from developing to developed,countries and the way such skilled migration a¤ects the source countries. In a …rst, descriptive section, we characterize the evolution and spatial distribution of the brain drain. We then provide a non- formal theoretical discussion of the various channels through,which,the brain drain impacts on

Frédéric Docquier; Hillel Rapoport

122

Scientific Data Processing for the ECT (Energetic Particle, Composition & Thermal Plasma Suite) on NASA's RBSP (Radiation belt Storm Probes) Mission  

NASA Astrophysics Data System (ADS)

Los Alamos is leading the Science Operations Center (SOC) for the Energetic Particle, Composition, and Thermal Plasma Suite (ECT) for NASA's upcoming Radiation Belt Storm Probe Mission (RBSP). Here we present the ECT team's facilities for making data available to both the ECT team and the public. The ECT-SOC will make extensive use of resources such as Autoplot, which will be tightly integrated into a modern version and process control system developed at LANL. In order to support the scientific investigations at the heart of the RBSP mission we make use of existing LANL resources to provide data in PSD format at constant adiabatic invariants, using the LANLGeoMag library and processing pipeline developed for the LANL DREAM (Dynamic Radiation Environment Assimilation Model). We intend to also present here the first runs of DREAM using the RBSP Space Weather Beacon real-time data.

Friedel, R. H.; Henderson, M. G.; Morley, S.; Reeves, G. D.; Niehof, J. T.

2012-12-01

123

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

124

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.

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

2014-01-01

125

Engineered porous metals for implants  

NASA Astrophysics Data System (ADS)

Interest is significant in patient-specific implants with the possibility of guided tissue regeneration, particularly for load-bearing implants. For such implants to succeed, novel design approaches and fabrication technologies that can achieve balanced mechanical and functional performance in the implants are necessary. This article is focused on porous load-bearing implants with tailored micro-as well as macrostructures using laser-engineered net shaping (LENS™), a solid freeform fabrication or rapid prototyping technique that can be used to manufacture patient-specific implants. This review provides an insight into LENS, some properties of porous metals, and the potential applications of this process to fabricate unitized structures which can eliminate longstanding challenges in load-bearing implants to increase their in-vivo lifetime, such as in a total hip prosthesis.

Vamsi Krishna, B.; Xue, Weichang; Bose, Susmita; Bandyopadhyay, Amit

2008-05-01

126

Prospective technology for system-on-a-chip: N2 implant followed by VHP O2 reoxidation  

NASA Astrophysics Data System (ADS)

A novel technique - N2 ion implant followed by vertical high pressure O2 re-oxidation in a furnace, capable of growing oxides of multiple thickness is presented. It is observed that the oxidation rate can be well modulated by varying the N2 I/I dose, and VHP O2 re-oxidation provides enhanced oxide growth rate and controls the nitrogen profile in the film, as compared to RTO or furnace O2 re-oxidation. Therefore, more than 500 percent differential oxide growth rate can be realized by using N2 I/I and VHP O2 re-oxidation. In addition, post-implant RTA N2 anneal is found to improve the channel carrier and alter the flat-band and threshold voltages without increasing the oxide thickness.

Luo, Tien-Ying; Al-Shareef, Husam N.; Brown, George A.; Watt, Victor H. C.; Karamcheti, Arun; Jackson, Mike D.; Huff, Howard R.; Evans, Bob; Lee, Chongmok; Luan, Hong-Fa; Kwong, Dim-Lee

2000-08-01

127

Prospective technology for system-on-a-chip: N2 implant followed by VHP O2 reoxidation  

Microsoft Academic Search

A novel technique - N2 ion implant followed by vertical high pressure O2 re-oxidation in a furnace, capable of growing oxides of multiple thickness is presented. It is observed that the oxidation rate can be well modulated by varying the N2 I\\/I dose, and VHP O2 re-oxidation provides enhanced oxide growth rate and controls the nitrogen profile in the film,

Tien-Ying Luo; Husam N. Al-Shareef; George A. Brown; Victor H. Watt; Arun Karamcheti; Mike D. Jackson; Howard R. Huff; Bob Evans; Chongmok Lee; Hong-Fa Luan; Dim-Lee Kwong

2000-01-01

128

Ect2 and MgcRacGAP regulate the activation and function of Cdc42 in mitosis  

PubMed Central

Although Rho regulates cytokinesis, little was known about the functions in mitosis of Cdc42 and Rac. We recently suggested that Cdc42 works in metaphase by regulating bi-orient attachment of spindle microtubules to kinetochores. We now confirm the role of Cdc42 by RNA interference and identify the mechanisms for activation and down-regulation of Cdc42. Using a pull-down assay, we found that the level of GTP-Cdc42 elevates in metaphase, whereas the level of GTP-Rac does not change significantly in mitosis. Overexpression of dominant-negative mutants of Ect2 and MgcRacGAP, a Rho GTPase guanine nucleotide exchange factor and GTPase activating protein, respectively, or depletion of Ect2 by RNA interference suppresses this change of GTP-Cdc42 in mitosis. Depletion of Ect2 also impairs microtubule attachment to kinetochores and causes prometaphase delay and abnormal chromosomal segregation, as does depletion of Cdc42 or expression of the Ect2 and MgcRacGAP mutants. These results suggest that Ect2 and MgcRacGAP regulate the activation and function of Cdc42 in mitosis.

Oceguera-Yanez, Fabian; Kimura, Kazuhiro; Yasuda, Shingo; Higashida, Chiharu; Kitamura, Toshio; Hiraoka, Yasushi; Haraguchi, Tokuko; Narumiya, Shuh

2005-01-01

129

Drug Delivery: Enabling Technology for Drug Discovery and Development. iPRECIO Micro Infusion Pump: Programmable, Refillable, and Implantable.  

PubMed

Successful drug delivery using implantable pumps may be found in over 12,500 published articles. Their versatility in delivering continuous infusion, intermittent or complex infusion protocols acutely or chronically has made them ubiquitous in drug discovery and basic research. The recent availability of iPRECIO(®), a programmable, refillable, and implantable infusion pump has made it possible to carry out quantitative pharmacology (PKPD) in single animals. When combined with specialized catheters, specific administration sites have been selected. When combined with radiotelemetry, the physiologic gold standard, more sensitive and powerful means of detecting drug induced therapeutic, and/or adverse effects has been possible. Numerous application examples are cited from iPRECIO(®) use in Japan, United States, and Europe with iPRECIO(®) as an enabling drug delivery device where the refillable and programmability functionality were key benefits. The ability to start/stop drug delivery and to have control periods prior dosing made it possible to have equivalent effects at a much lower dose than previously studied. Five different iPRECIO(®) applications are described in detail with references to the original work where the implantable, refillable, and programmable benefits are demonstrated with their different end-points. PMID:21863140

Tan, Tsung; Watts, Stephanie W; Davis, Robert Patrick

2011-01-01

130

Drug Delivery: Enabling Technology for Drug Discovery and Development. iPRECIO® Micro Infusion Pump: Programmable, Refillable, and Implantable  

PubMed Central

Successful drug delivery using implantable pumps may be found in over 12,500 published articles. Their versatility in delivering continuous infusion, intermittent or complex infusion protocols acutely or chronically has made them ubiquitous in drug discovery and basic research. The recent availability of iPRECIO®, a programmable, refillable, and implantable infusion pump has made it possible to carry out quantitative pharmacology (PKPD) in single animals. When combined with specialized catheters, specific administration sites have been selected. When combined with radiotelemetry, the physiologic gold standard, more sensitive and powerful means of detecting drug induced therapeutic, and/or adverse effects has been possible. Numerous application examples are cited from iPRECIO® use in Japan, United States, and Europe with iPRECIO® as an enabling drug delivery device where the refillable and programmability functionality were key benefits. The ability to start/stop drug delivery and to have control periods prior dosing made it possible to have equivalent effects at a much lower dose than previously studied. Five different iPRECIO® applications are described in detail with references to the original work where the implantable, refillable, and programmable benefits are demonstrated with their different end-points.

Tan, Tsung; Watts, Stephanie W.; Davis, Robert Patrick

2011-01-01

131

Intravascular implant  

US Patent & Trademark Office Database

The invention has for its object the provision of an intravascular implant that has mechanical characteristics and physiological characteristics and is very low in cell cytotoxicity and provides an intravascular implant having an implant body made of a metal material that contains gadolinium and magnesium and is free of yttrium.

2012-10-23

132

Ion Implantation in Gallium Arsenide  

Microsoft Academic Search

Ion implantation is a useful method to incorporate dopants into semiconductors. Understanding implantation processes is essential to the advancement of solid state technology. Because of its technical importance, gallium arsenide (GaAs) was chosen for this study. Hall effect, x-ray diffraction, and electrochemical capacitance-voltage (CV) profiling were used to study activation of silicon implants as functions of dose and annealing temperature

John Hamilton Madok

1993-01-01

133

Ion-implanted microwave MOSFET's  

Microsoft Academic Search

One-µm n-channel silicon MOSFET's have been fabricated using ion-implantation techniques. The gate structures are self-aligned, with negligible overlapping capacitance. Because of low-temperature aspects of the ion-implantation and post-implantation annealing processes, they can be incorporated at any stage of the conventional silicon technology. The devices exhibit characteristics consistent with the inversion layer electron velocity saturation model. The transconductance in the saturation

F. F. Fang; B. L. Crowder

1970-01-01

134

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

2014-04-01

135

Changes in Heart Rate Variability before and after ECT in the Treatment of Resistant Major Depressive Disorder.  

PubMed

Background: In this study, we aimed to evaluate the effects of electroconvulsive therapy (ECT) on cardiac autonomic functions (CAF) in patients with major depressive disorder (MDD) using heart rate variability (HRV) analysis. Method: Fourteen men joined the study. Nine ECTs were administered. Holter monitoring was performed before treatment and at the end of the first, third and sixth weeks of the treatment. The Hamilton Depression Rating Scale (HAM-D) was used to assess symptom severity. Results: Seven patients responded to ECT. There was a change of 2-hour resting HF, pNN50 and RMSSD scores between week 0 and week 6. This change was not significant after week 1 and week 3. HRV values did not differ when we grouped the patients as responders and non-responders to ECT except the 2-hour resting HF value of responders between week 0 and week 6 and the 24-hour HF value of non-responders between week 1 and week 6. All observed changes showed a decrease in parameters. Overall, the LF/HF ratio did not change significantly in either analysis. HRV values did not correlate with HAM-D scores and no relation was found between treatment response and HRV analysis. After Benferroni-adjustment none of the changes were found statistically significant. Limitations: The limitations of the study are the small sample size and the absence of healthy controls. Conclusions: A consistent change in HRV was not observed in response to ECT in patients with MDD. Accepting the HRV as a promising surrogate marker of autonomic activity, ECT does not cause a significant change in nine male treatment resistant MDD patients cardiac autonomic functions. PMID:24029110

Bozkurt, Ali; Barcin, Cem; Isintas, Mehmet; Ak, Mehmet; Erdem, Murat; Ozmenler, K Nahit

2013-01-01

136

Cochlear implants in China.  

PubMed

China has approximately 6 million totally deaf people according to an official survey conducted in 1990, although the actual number is probably higher. A primary cause of deafness is the use of ototoxic drugs. There does not appear to be any emergent deaf culture in China at present. As the only available medical device that can restore partial hearing to a totally deaf person, the cochlear implant has been in development in China since 1979. This paper provides an overview of cochlear implants in China and is based on a review of published materials, visits to research institutes and hospitals, and personal communication with Chinese colleagues. As of 1993, about 1,000 deaf people, including 50 children below age 12 years, have received four types of single-electrode cochlear implants that were developed and fabricated by institutions in China. These single-electrode devices have provided an aid to lip reading, but are no longer in use due to their inability to produce open-set speech recognition. Present implant research in China focuses on development of multi-electrode devices. Basic research in electrical stimulation is relatively lacking and standardized audiological evaluation for cochlear implant effectiveness needs to be developed. The present economic growth and legal system reform in China, combined with advances in implant technology, may make it possible to produce an affordable yet effective cochlear implant system. This paper discusses cochlear implants only in China, but the social and economic factors are similar in many developing countries in Asia, South America, Eastern Europe, and Africa, where a low-cost, high-performance cochlear implant system is also needed. PMID:8561684

Zeng, F G

1995-01-01

137

0.5 {mu}m E/D AlGaAs/GaAs heterostructure field effect transistor technology with DFET threshold adjust implant  

SciTech Connect

A doped-channel heterostructure field effect transistor (H-FET) technology has been developed with self-aligned refractory gate processing and using both enhancement- and depletion-mode transistors. D-HFET devices are obtained with a threshold voltage adjust implant into material designed for E-HFET operation. Both E- and D-HFETs utilize W/WSi bilayer gates, sidewall spacers, and rapid thermal annealing for controlling short channel effects. The 0.5 {mu}m E- HFETs (D-HFETs) have been demonstrated with transconductance of 425 mS/mm (265-310 mS/mm) and f{sub t} of 45-50 GHz. Ring oscillator gate delays of 19 ps with a power of 0.6 mW have been demonstrated using direct coupled FET logic. These results are comparable to previous doped-channel HFET devices and circuits fabricated by selective reactive ion etching rather than ion implantation for threshold voltage adjustment.

Baca, A.G.; Sherwin, M.E.; Zolper, J.C.; Shul, R.J.; Briggs, R.D.; Heise, J.A.; Robertson, P.J.; Hafich, M.F.

1997-04-01

138

SEMICONDUCTOR MATERIALS: Growth of strained-Si material using low-temperature Si combined with ion implantation technology  

NASA Astrophysics Data System (ADS)

In order to fabricate strained-Si MOSFETs, we present a method to prepare strained-Si material with high-quality surface and ultra-thin SiGe virtual substrate. By sandwiching a low-temperature Si (LT-Si) layer between a Si buffer and a pseudomorphic Si0.8Ge0.2 layer, the surface roughness root mean square (RMS) is 1.02 nm and the defect density is 106 cm-2 owing to the misfit dislocations restricted to the LT-Si layer and the threading dislocations suppressed from penetrating into the Si0.8Ge0.2 layer. By employing P+ implantation and rapid thermal annealing, the strain relaxation degree of the Si0.8Ge0.2 layer increases from 85.09% to 96.41% and relaxation is more uniform. Meanwhile, the RMS (1.1 nm) varies a little and the defect density varies little. According to the results, the method of combining an LT-Si layer with ion implantation can prepare high-quality strained-Si material with a high relaxation degree and ultra-thin SiGe virtual substrate to meet the requirements of device applications.

Hongdong, Yang; Qi, Yu; Xiangzhan, Wang; Jingchun, Li; Ning, Ning; Mohua, Yang

2010-06-01

139

Comparison between the effect of liothyronine and piracetam on personal information, orientation and mental control in patients under treatment with ECT  

PubMed Central

Objective: The study aimed to compare the effect of liothyronine and piracetam on three subscales of the Wechsler memory test on patients under treatment with ECT. Materials and Methods: In a double blind clinical trial, 60 of 99 patients between 20 and 45 years old, under treatment with ECT were studied in three groups. Patients in the allocation groups received liothyronine, piracetam, or placebo, from the first session of ECT until 1 month after the last session of ECT. Personal information, orientation, and mental control were tested in the participants at first, fourth, and last session of ECT and 1 month after the last session of ECT. Data were analyzed with Repeated measure ANOVA using SPSS 13. Results: There wasn’t any significant difference among three groups in demographic characteristics before the study and number of ECT sessions (P=0.684). After intervention, a significant difference in memory scores was seen in third and fourth assessment sessions (0.002). Orientation subscales showed a significant difference among four assessment sessions (P=0.001). Personal information and mental control never decreased in the liothyronine group. There was no significant difference among three studied groups in personal information, orientation, and mental control (P>0.05). Conclusion: Memory changes due to ECT may be limited to some parts of memory like orientation. More powerful studies for comparison between the effect of liothyronine and placebo are necessary.

Ghafur, Mousavi Seyed; Saadat, Mohammad; Maraci, Mohamad Reza; Bagherian, Reza S.; Mazaheri, Mina

2012-01-01

140

High Productivity Implantation ``PARTIAL IMPLANT''  

NASA Astrophysics Data System (ADS)

The patterned ion implantation ``PARTIAL IMPLANT'' has been developed as a productivity improvement tool. The Partial Implant can form several different ion dose areas on the wafer surface by controlling the speed of wafer moving and the stepwise rotation of twist axis. The Partial Implant system contains two implant methods. One method is ``DIVIDE PARTIAL IMPLANT,'' that is aimed at reducing the consumption of the wafer. The Divide Partial Implant evenly divides dose area on one wafer surface into two or three different dose part. Any dose can be selected in each area. So the consumption of the wafer for experimental implantation can be reduced. The second method is ``RING PARTIAL IMPLANT'' that is aimed at improving yield by correcting electrical characteristic of devices. The Ring Partial Implant can form concentric ion dose areas. The dose of wafer external area can be selected to be within plus or minus 30% of dose of wafer central area. So the electrical characteristic of devices can be corrected by controlling dose at edge side on the wafer.

Hino, Masayoshi; Miyamoto, Naoki; Sakai, Shigeki; Matsumoto, Takao

2008-11-01

141

The influence of heavily doped buried layer implants on electrostatic discharge (ESD), latchup, and a silicon germanium heterojunction bipolar transistor in a BiCMOS SiGe technology  

Microsoft Academic Search

This paper will demonstrate the effect of heavily doped buried layers (HDBL) on electrostatic discharge protection, latchup, and silicon germanium (SiGe) heterojunction bipolar transistors (HBT). Heavily doped buried layers (HDBL) implants, in prior publications, have demonstrated improvements in latchup robustness in low-doped substrate wafer technology. The influence of HDBL on MOSFET ESD protection has also been demonstrated. In this paper,

S. Voldman; L. Lanzerotti; W. Morris; L. Rubin

2004-01-01

142

Ion Implantation  

NASA Astrophysics Data System (ADS)

In this tutorial we describe the basic principles of the ion implantation technique and we demonstrate that emission Mössbauer spectroscopy is an extremely powerful technique to investigate the atomic and electronic configuration around implanted atoms. The physics of dilute atoms in materials, the final lattice sites and their chemical state as well as diffusion phenomena can be studied. We focus on the latest developments of implantation Mössbauer spectroscopy, where three accelerator facilities, i.e., Hahn-Meitner Institute Berlin, ISOLDE-CERN and RIKEN, have intensively been used for materials research in in-beam and on-line Mössbauer experiments immediately after implantation of the nuclear probes.

Langouche, G.; Yoshida, Y.

143

Implantable insulin delivery system  

SciTech Connect

An insulin delivery system suitable for experimental implants and external use has been developed to study glucose control for diabetics. The programmable system developed at Sandia National Laboratories, in conjunction with the University of New Mexico School of Medicine, employs miniature electronics and mechanical technologies developed for use in other Department of Energy programs.

Love, J.T.; Gaona, J.I. Jr.

1981-01-01

144

Oxygen implanter for simox  

Microsoft Academic Search

Interest in silicon or) insulator (SOI) technology has led to the development of several alternatives to silicon on sapphire. One of the most promising techniques makes use of an ion implanter to form a buried oxide layer directly in the silicon substrate. To have useful single crystalline silicon on top of the oxide layer, it is necessary to do the

M. Guerra; V. Benveniste; G. Ryding; D. H. Douglas-Hamilton; M. Reed; G. Gagne; A. Armstrong; M. Mack

1985-01-01

145

Cognitive and radiological eff ects of radiotherapy in patients with low-grade glioma: long-term follow-up  

Microsoft Academic Search

Background Our previous study on cognitive functioning among 195 patients with low-grade glioma (LGG) a mean of 6 years after diagnosis suggested that the tumour itself, rather than the radiotherapy used to treat it, has the most deleterious eff ect on cognitive functioning; only high fraction dose radiotherapy (>2 G y) resulted in signifi cant added cognitive deterioration. The present

Linda Douw; Martin Klein; Selene S A A Fagel; Josje van den Heuvel; Martin J B Taphoorn; Neil K Aaronson; Tjeerd J Postma; W Peter Vandertop; Jacob J Mooij; Rudolf H Boerman; Guus N Beute; Jasper D Sluimer; Ben J Slotman; Jaap C Reijneveld; Jan J Heimans

2009-01-01

146

Sequential Cyk-4 binding to ECT2 and FIP3 regulates cleavage furrow ingression and abscission during cytokinesis  

PubMed Central

Cytokinesis is a highly regulated and dynamic event that involves the reorganization of the cytoskeleton and membrane compartments. Recently, FIP3 has been implicated in targeting of recycling endosomes to the mid-body of dividing cells and is found required for abscission. Here, we demonstrate that the centralspindlin component Cyk-4 is a FIP3-binding protein. Furthermore, we show that FIP3 binds to Cyk-4 at late telophase and that centralspindlin may be required for FIP3 recruitment to the mid-body. We have mapped the FIP3-binding region on Cyk-4 and show that it overlaps with the ECT2-binding domain. Finally, we demonstrate that FIP3 and ECT2 form mutually exclusive complexes with Cyk-4 and that dissociation of ECT2 from the mid-body at late telophase may be required for the recruitment of FIP3 and recycling endosomes to the cleavage furrow. Thus, we propose that centralspindlin complex not only regulates acto-myosin ring contraction but also endocytic vesicle transport to the cleavage furrow and it does so through sequential interactions with ECT2 and FIP3.

Simon, Glenn C; Schonteich, Eric; Wu, Christine C; Piekny, Alisa; Ekiert, Damian; Yu, Xinzi; Gould, Gwyn W; Glotzer, Michael; Prekeris, Rytis

2008-01-01

147

[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

148

Breast Implants  

MedlinePLUS

... result of an original surgery. There are two types of breast implants approved for sale in the United States: saline- ... Encourage reporting of adverse events associated with breast implants through our Medwatch Reporting System. Related Links Medscape Interview with FDA staff on ...

149

Risks of Breast Implants  

MedlinePLUS

... Booklet Anaplastic Large Cell Lymphoma (ALCL) Other Resources Risks of Breast Implants Risks of Breast Implants Implant ... Getting Breast Implants (Available in text and PDF) Risks of Breast Implants Some of the complications and ...

150

Bilateral cochlear implantation.  

PubMed

Cochlear implantation (CI) is the standard of care for the treatment of children and adults with bilateral severe-to-profound sensorineural hearing loss. Because the ultimate and continuous goal of CI teams is to improve patient performance, a potential method is bilateral CI. The potential benefits of bilateral CI include binaural summation, squelch, equivalent head shadow for each ear, improved hearing in noise, sound localization ability, and spatial release from masking. The potential disadvantages include additional or prolonged surgical procedure, unproven cost/benefit profile, and the elimination of the ability to use future technologies and/or medical therapies in the implanted ear. PMID:22115683

Wanna, George B; Gifford, René H; McRackan, Theodore R; Rivas, Alejandro; Haynes, David S

2012-02-01

151

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

152

The use of VIRBO and Autoplot within the automated processing chain for data from the ECT team for the upcoming RBSP mission  

NASA Astrophysics Data System (ADS)

Los Alamos is leading the Science Operations Center (SOC) for the Energetic Particle, Composition, and Thermal Plasma Suite (ECT) for NASA's upcoming Radiation Belt Storm Probe Mission (RBSP). This paper will present the ECT team's plans for making data available to both the ECT team and the public. The ECT-SOC will make extensive use of resources made available through the VIRBO Virtual observatory, and tools such as Autoplot and PaPCo, which will be tightly integrated into a modern version and process control system developed at LANL. ECT data will be available in quicklook and validated format, both as browsable images and ISTP-comliant CDF files. Our process control system will enable us to maintain full control over the version history of all input and output files and individual processes, allowing the re-creation of and specific version of a data product. In the absence of real ECT data we will show examples using existing data from LANL's energetic particle and plasma instruments as "proxies" for the ECT instrumentation HOPE (plasma), MagEIS (high energy) and REPT (very high energies).

Friedel, R. H.; Faden, J.; Weigel, R. S.

2011-12-01

153

ECT imaging with Tc(V)-99m dimercaptosuccinic acid useful to detect lung metastases of osteosarcoma  

SciTech Connect

ECT imaging, using Tc(V)-99m dimercaptosuccinic acid (Tc(V)-DMS) was performed in two patients with lung metastasis of osteosarcoma, and the results were compared with those of CT scan. Clear accumulation of Tc(V)-DMS was recognized in all cases in the same area that CT scans demonstrated. Tc(V)-DMS was labeled under optimal pH 8, had very low SnCl/sub 2/ concentrations, an equilibrium between a stable form and a dissociated form of anion TcO/sub 4/(3-) structurally similar to PO/sub 4/(3-), and was postulated for tumor uptake. Considering this proposed mechanism for Tc(V)-DMS uptake by tumor cells, ECT imaging using this tracer could be of use in the early detection of lung metastasis of osteosarcoma.

Ohta, H.; Ishii, M.; Yoshizumi, M.; Endo, K.; Fujita, T.; Nakajima, T.; Sakahara, H.; Torizuka, K.; Kotoura, Y.; Yokoyama, A.

1985-01-01

154

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

155

Retinal Implants for Blind Patients  

NASA Astrophysics Data System (ADS)

Recently, very promising results have been obtained in clinical trials with eye-prostheses for the blind. There is a chance that advances in surgical techniques, microelectronics design, and material science may lead to the first really useful applications of retinal implants in the near future. This chapter will focus on the actual status of subretinal surgery and implant technologies. Opportunities and limitations of the different technologies will be discussed in terms of patients benefit and technological challenges. Finally, a vision on how the devices may work and look like in the future will be given.

Rothermel, Albrecht

156

Characterization of the Edge Crack Torsion (ECT) Test for Mode III Fracture Toughness Measurement of Laminated Composites  

NASA Technical Reports Server (NTRS)

The edge crack torsion (ECT) test is designed to initiate mode III delamination growth in composite laminates. An ECT specimen is a rectangular laminate, containing an edge delamination at the laminate mid-plane. Torsion load is applied to the specimens, resulting in relative transverse shear sliding of the delaminated faces. The test data reduction schemes are intended to yield initiation values of critical mode III strain energy release rate, G(sub IIIc), that are constant with delamination length. The test has undergone several design changes during its development. The objective of this paper was to determine the suitability of the current ECT test design as a mode III fracture test. To this end, ECT tests were conducted on specimens manufactured from IM7/8552 and specimens made from S2/8552 tape laminates. Several specimens, each with different delamination lengths are tested. Detailed, three-dimensional finite element analyses of the specimens were performed. The analysis results were used to calculate the distribution of mode I, mode II, and mode III strain energy release rate along the delamination front. The results indicated that mode III-dominated delamination growth would be initiated from the specimen center. However, in specimens of both material types, the measured values of G(sub IIIc) exhibited significant dependence on delamination length. Furthermore, there was a large amount of scatter in the data. Load-displacement response of the specimens exhibited significant deviation from linearity before specimen failure. X-radiographs of a sample of specimens revealed that damage was initiated in the specimens prior to failure. Further inspection of the failure surfaces is required to identify the damage and determine that mode III delamination is initiated in the specimens.

Ratcliffe, James G.

2004-01-01

157

Impianti Cocleari: Indagine su Stato dell'arte, Problematiche Riscontrate, Aspetti Clinici e Normativi (Cochlear Implants; A Study on technology, Problems Found Clinical and Regulation Aspects).  

National Technical Information Service (NTIS)

The Istituto Superiore di Sanita (the National Institute of Health in Italy) has started a preliminary study on the cochlear implant but basic to the future aspects. In this first phase it has been investigated the evolution of the cochlear implants, from...

D. Giansanti G. Maccioni M. Grigioni S. Morelli

2009-01-01

158

The Guanine Nucleotide Exchange Factors Trio, Ect2, and Vav3 Mediate the Invasive Behavior of Glioblastoma  

PubMed Central

Malignant gliomas are characterized by their ability to invade normal brain tissue. We have previously shown that the small GTPase Rac1 plays a role in both migration and invasion in gliomas. Here, we aim to identify Rac-activating guanine nucleotide exchange factors (GEFs) that mediate glioblastoma invasiveness. Using a brain tumor expression database, we identified three GEFs, Trio, Ect2, and Vav3, that are expressed at higher levels in glioblastoma versus low-grade glioma. The expression of these GEFs is also associated with poor patient survival. Quantitative real-time polymerase chain reaction and immunohistochemical analyses on an independent set of tumors confirmed that these GEFs are overexpressed in glioblastoma as compared with either nonneoplastic brain or low-grade gliomas. In addition, depletion of Trio, Ect2, and Vav3 by siRNA oligonucleotides suppresses glioblastoma cell migration and invasion. Depletion of either Ect2 or Trio also reduces the rate of cell proliferation. These results suggest that targeting GEFs may present novel strategies for anti-invasive therapy for malignant gliomas.

Salhia, Bodour; Tran, Nhan L.; Chan, Amanda; Wolf, Amparo; Nakada, Mitsutoshi; Rutka, Fiona; Ennis, Matthew; McDonough, Wendy S.; Berens, Michael E.; Symons, Marc; Rutka, James T.

2008-01-01

159

Characterization of the Edge Crack Torsion (ECT) Test for Mode III Fracture Toughness Measurement of Laminated Composites  

NASA Technical Reports Server (NTRS)

The edge crack torsion (ECT) test is designed to initiate mode III delamination growth in composite laminates. The test has undergone several design changes during its development. The objective of this paper was to determine the suitability of the current ECT test design a mode III fracture test. To this end, ECT tests were conducted on specimens manufactured from IM7/8552 and S2/8552 tape laminates. Three-dimensional finite element analyses were performed. The analysis results were used to calculate the distribution of mode I, mode II, and mode III strain energy release rate along the delamination front. The results indicated that mode IIIdominated delamination growth would be initiated from the specimen center. However, in specimens of both material types, the measured values of GIIIc exhibited significant dependence on delamination length. Load-displacement response of the specimens exhibited significant deviation from linearity before specimen failure. X-radiographs of a sample of specimens revealed that damage was initiated in the specimens prior to failure. Further inspection of the failure surfaces is required to identify the damage and determine that mode III delamination is initiated in the specimens.

Ratcliffe, James G.

2004-01-01

160

Dynamics of spiral bubble plume motion in the entrance region of bubble columns and three-phase fluidized beds using 3D ECT  

Microsoft Academic Search

In this study, we have developed, for the first time in the field, a ‘dynamic’ three-dimensional image reconstruction technique for electrical capacitance tomography (ECT) imaging based on a neural-network multi-criterion optimization (NNMOIRT). This development enables a real time, 3D imaging of a moving object to be realized. The image reconstruction scheme of the 3D ECT is established by introducing a

W. Warsito; L.-S. Fan

2005-01-01

161

Implant-Associated Infection  

Microsoft Academic Search

\\u000a During the last 50 years, medical devices have gained growing importance (Darouiche 2004). On the one side, there is an increasing\\u000a need due to the higher median age of the population suffering from degenerative diseases. On the other side, technology evolved\\u000a and many functions can be replaced by novel medical devices, such as cochlear implants, brain stimulators, and ventricular\\u000a assist

Werner Zimmerli; Andrej Trampuz

162

Implant-Supported Denture  

MedlinePLUS

... interfere with the placement of implants. The time frame to complete the implant and denture depends on ... the type of implant used. The shortest time frame for standard implants is about five months for ...

163

First Results from the Radiation Belt Storm Probes (RBSP) - Energetic particle, Composition, and Thermal plasma (ECT) Suite Science Investigation  

NASA Astrophysics Data System (ADS)

The Radiation Belt Storm Probes (RBSP) - Energetic Particle, Composition, and Thermal Plasma (ECT) suite 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 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 RBSP 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 they 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 questions and then show first scientific results derived from the ECT suite on the dual RBSP spacecraft. We anticipate that these results will include progress toward resolving primary RBSP 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, H. E.; Reeves, G. D.

2012-12-01

164

[Dental implants. History and tissue reactions of implants].  

PubMed

Dental implant (oral implant) is totally based on dentistry and the progress in its technology. On this occasion, dental implant are described from the standpoints of experimental pathology and clinical pathology. Demands for improved dental technology have brought significant developments in the dental implant field. Based upon the latest general implant technology, improvements in dental implant technology have primarily taken the form of better materials and designs historically. The object of these developments has been to provide the patients with restored teeth whose structure and function are asymptotically close to those of natural teeth while enhancing recovery of the occlusion function and improving aesthetic quality by means of applying technique of oral surgery (including periodontics) and prosthodontics. The basic structure of the dental implant consists of the substructure buried in the jaw bone, the junction, and the superstructure projected into the oral cavity. These three items correspond respectively to the root, the neck, and the crown of a natural tooth. However, neither the structure nor the function of such an implant body can be identical to those of a natural standing tooth. Physiologic metabolism, which is present in the latter, does not exist in the former. Therefore, it should always be remembered that even modern technology and materials can not reproduce the oral conditions identical to those produced by physiologic tissue and functions which are subject to chronological change. We should bear in mind that this system, unlike those made up by inter-material relations or inter-organic relations is made of an artificial structure, functions apart from the natural organs, and serves only as a substitute. Certain inherently unstable factors are inevitable. For example, radiographic findings confirm that V-shaped radiolucency by bone resorption in the alveolar bone surrounding the tooth neck is always more extensive than in the case of natural teeth. First study: Histopathological Studies of Tissue Reaction for Implant Materials(Fig. 4-10). This study is a basic experiment to help the development of implant materials used in repairing extraction wounds of teeth and bone defects. It is desirable that the materials should be preservable, easy to process, and with high histocompatibility. Examined materials are DCFF or non-DCFF treated bone matrices (grafts) of rats and human, and single crystal ceramics (Al2O3). DCFF treatment is a procedure of decalcifying, defatting and freeze-drying bones and ligaments of animals after fixation in formalin for immunological tolerance (M. KATAGIRI got a patent for this invention in America, West Germany and Japan, Table 1).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2489285

Katagiri, M

1989-10-01

165

Implantable enzyme amperometric biosensors.  

PubMed

The implantable enzyme amperometric biosensor continues as the dominant in vivo format for the detection, monitoring and reporting of biochemical analytes related to a wide range of pathologies. Widely used in animal studies, there is increasing emphasis on their use in diabetes care and management, the management of trauma-associated hemorrhage and in critical care monitoring by intensivists in the ICU. These frontier opportunities demand continuous indwelling performance for up to several years, well in excess of the currently approved seven days. This review outlines the many challenges to successful deployment of chronically implantable amperometric enzyme biosensors and emphasizes the emerging technological approaches in their continued development. The foreign body response plays a prominent role in implantable biotransducer failure. Topics considering the approaches to mitigate the inflammatory response, use of biomimetic chemistries, nanostructured topographies, drug eluting constructs, and tissue-to-device interface modulus matching are reviewed. Similarly, factors that influence biotransducer performance such as enzyme stability, substrate interference, mediator selection and calibration are reviewed. For the biosensor system, the opportunities and challenges of integration, guided by footprint requirements, the limitations of mixed signal electronics, and power requirements, has produced three systems approaches. The potential is great. However, integration along the multiple length scales needed to address fundamental issues and integration across the diverse disciplines needed to achieve success of these highly integrated systems, continues to be a challenge in the development and deployment of implantable amperometric enzyme biosensor systems. PMID:22516142

Kotanen, Christian N; Moussy, Francis Gabriel; Carrara, Sandro; Guiseppi-Elie, Anthony

2012-05-15

166

Size at Implantation Affects Growth of Juvenile Steelhead Implanted with 12-mm Passive Integrated Transponders  

Microsoft Academic Search

Passive integrated transponder (PIT) tags have led to greater understanding of fish growth, survival, predation, migration, behavior, and the effects of human-caused environmental manipulation. Technological advances have reduced the size of PIT tags, permitting their implantation into smaller fish. To reap the benefits of PIT tag technology, implantation must not adversely impact growth, survival, or behavior. Steelhead Oncorhynchus mykiss parr

Christopher P. Tatara

2009-01-01

167

Cochlear Implants  

MedlinePLUS

... portion that sits behind the ear and a second portion that is surgically placed under the skin (see figure). An implant has the following parts: A microphone, which picks up sound from the environment. A speech processor, which selects and arranges sounds ...

168

Integrated electronics platforms for wireless implantable biosensors  

Microsoft Academic Search

Wireless intelligent sensing devices implanted in animals or in humans have rigorous size, power, functional, and reliability requirements. Miniaturized electronics integrated in part or in whole, is necessary to achieve these goals. Electronic design considerations, often unique to implants, takes into account the medical application, transducer technology, telemetry, and level of integration. In this paper, we discuss the salient issues

R. H. Farahi; T. L. Ferrell; A. Guiseppi-Elie; P. Hansen

2007-01-01

169

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

170

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

171

Leukocyte Gene Expression in Patients with Medication Refractory Depression before and after Treatment with ECT or Isoflurane Anesthesia: A Pilot Study  

PubMed Central

Objective. To evaluate leukocyte gene expression for 9 selected genes (mRNAs) as biological markers in patients with medication refractory depression before and after treatment with ECT or isoflurane anesthesia (ISO). Methods. In a substudy of a nonrandomized open-label trial comparing effects of ECT to ISO therapy, blood samples were obtained before and after treatment from 22 patients with refractory depression, and leukocyte mRNA was assessed by quantitative PCR. Patients' mRNAs were also compared to 17 healthy controls. Results. Relative to controls, patients before treatment showed significantly higher IL10 and DBI and lower ADRA2A and ASIC3 mRNA (P < 0.025). Both ECT and ISO induced significant decreases after treatment in 4 genes: IL10, NR3C1, DRD4, and Sult1A1. After treatment, patients' DBI, ASIC3, and ADRA2A mRNA remained dysregulated. Conclusion. Significant differences from controls and/or significant changes after ECT or ISO treatment were observed for 7 of the 9 mRNAs studied. Decreased expression of 4 genes after effective treatment with either ECT or ISO suggests possible overlap of underlying mechanisms. Three genes showing dysregulation before and after treatment may be trait-like biomarkers of medication refractory depression. Gene expression for these patients has the potential to facilitate diagnosis, clarify pathophysiology, and identify potential biomarkers for treatment effects.

Iacob, E.; Tadler, S. C.; Light, K. C.; Weeks, H. R.; Smith, K. W.; White, A. T.; Hughen, R. W.; VanHaitsma, T. A.; Bushnell, L. A.; Light, A. R.

2014-01-01

172

Ion Implantation in Gallium Arsenide  

NASA Astrophysics Data System (ADS)

Ion implantation is a useful method to incorporate dopants into semiconductors. Understanding implantation processes is essential to the advancement of solid state technology. Because of its technical importance, gallium arsenide (GaAs) was chosen for this study. Hall effect, x-ray diffraction, and electrochemical capacitance-voltage (CV) profiling were used to study activation of silicon implants as functions of dose and annealing temperature and time. The annealing of crystalline damage and activation of dopants proceeds in a definite sequence. Implantation damage is annealed at approximately 625^ circC, with activation taking place between 625 and 675^circC. The electron profiles arising from Si implantation into GaAs possess long tails. Increasing the annealing temperature to greater than 900^circC results in a shortening of the tail because of the formation of an unknown acceptor defect. This result is reproducible and was used to enhance the performance of GaAs JFETs. Co-implantation of In or Ga with C was investigated by Local Vibrational Mode Spectroscopy (LVM), Rutherford Backscattering (RBS), Particle-Induced X-Ray Emission (PIXE), Photoluminescence (PL), and Hall effect. The dose of the C was 5 times 10^ {14} cm^{-2} 27 keV, while the doses of In, 185 keV, or Ga, 160 keV, ranged from 5 times 10 ^{13} to 5 times 10^{15} cm ^{-2}. The data shows that 99% of the C, when implanted alone and annealed, is not located as isolated, substitutional atoms on either sublattice, but in non-substitutional, inactive sites. The co-implanted ion acts to increase both the concentration of C _{rm As} ((C_ {rm As})) and the sheet hole concentration. For co-implant doses of 5 times 10 ^{13} and 5 times 10^{14} cm ^{-2}, these values are in good agreement. A co-implant dose of 5 times 10^{15} cm ^{-2} results in a hole concentration that is 30% less than the (C_{rm As}) and the co-implanted ions begin to occupy non-substitutional sites. The reduction in the concentration of holes due to C_{rm As} appears to be caused by a compensating donor defect which limits the maximum sheet hole concentration obtainable by the co-implantation technique in GaAs.

Madok, John Hamilton

173

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.

Tang, Elieza

2013-01-01

174

Photobiomodulation and implants: implications for dentistry.  

PubMed

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; Arany, Praveen

2013-12-01

175

Alloy May Improve Durability of Dental Implants.  

National Technical Information Service (NTIS)

This citation summarizes a one-page announcement of technology available for utilization. A porous metal implant designed to support removable dentures and fixed bridges and to replace missing teeth proved successful in tests on monkeys at the University ...

1983-01-01

176

Pre-implantation genetic diagnosis  

Microsoft Academic Search

Pre-implantation genetic diagnosis (PGD) was developed in the UK over 10 years ago. There are now more than 40 centres worldwide carrying out PGD and 150 babies have been born after genetic testing on day 3 of development, at the cleavage stage. This review covers the current status of PGD, the technology used and the types of genetically determined diseases

Joy D. A. Delhanty; Joyce C. Harper

2000-01-01

177

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

178

Knee Replacement Implants  

MedlinePLUS

... and Knee Replacement Rehabilitation News News Multimedia Resources Knee Replacement Implants Introduction | Implant Design | Implant Components | Fixed- ... Article Text Size: + | - Next Your doctor may recommend knee replacement surgery if you have severe knee pain ...

179

Implantable visual prostheses.  

PubMed

Visual impairment and blindness is primarily caused by optic neuropathies like injuries and glaucomas, as well as retinopathies like agerelated macular degeneration (MD), systemic diseases like diabetes, hypertonia and hereditary retinitis pigmentosa (RP). These pathological conditions may affect retinal photoreceptors, or retinal pigment epithelium, or particular subsets of retinal neurons, and in particular retinal ganglion cells (RGCs). The RGCs which connect the retina with the brain are unique cells with extremely long axons bridging the distance from the retina to visual relays within the thalamus and midbrain, being therefore vulnerable to heterogeneous pathological conditions along this pathway. When becoming mature, RGCs loose the ability to divide and to regenerate their accidentally or experimentally injured axons. Consequently, any loss of RGCs is irreversible and results to loss of visual function. The advent of micro- and nanotechnology, and the construction of artificial implants prompted to create visual prostheses which aimed at compensating for the loss of visual function in particular cases. The purpose of the present contribution is to review the considerable engineering expertise that is essential to fabricate current visual prostheses in connection with their functional features and applicability to the animal and human eye. In this chapter, 1) Retinal and cortical implants are introduced, with particular emphasis given to the requirements they have to fulfil in order to replace very complex functions like vision. 2) Advanced work on material research is presented both from the technological and from the biocompatibility aspect as prerequisites of any perspectives for implantation. 3) Ultimately, experimental studies are presented showing the shaping of implants, the procedures of testing their biocompatibility and essential modifications to improve the interfaces between technical devices and the biological environment. The review ends by pointing to future perspectives in the rapidly accelerating process of visual prosthetics and in the increasing hope that restoration of the visual system becomes reality. PMID:17691336

Thanos, S; Heiduschka, P; Stupp, T

2007-01-01

180

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

181

Breast Implants: An Information Update.  

National Technical Information Service (NTIS)

Contents: History of Breast Implants; Availability of Implants; The Surgery; Surgical Risks of Implants; Other Implant-Related Risks; Illness and Conditions Elsewhere in The Body and Breast Implants; Special Medical and Physical Considerations; Breast Imp...

1997-01-01

182

A Comparison of Pectoral and Abdominal Transvenous Defibrillator Implantation: Analysis of Costs and Outcomes  

Microsoft Academic Search

Traditionally cardioverter-defibrillator implantation was performed by surgeons under general anesthesia. However, with advances in lead and pulse generator technology, the surgical implantation technique has been simplified and routine pectoral pulse generator placement without general anesthesia is now possible. To assess the economic benefit of pectoral implantation, we analyzed 43 consecutive initial transvenous defibrillator implantations. The patients were grouped according to

Michael R Gold; Deborah Froman; Neal G. Kavesh; Robert W. Peters; Andrew Foster; Stephen R Shorofsky

1998-01-01

183

Combined Intacs and Posterior Chamber Toric Implantable Collamer Lens Implantation for Keratoconic Patients with Extreme Myopia  

Microsoft Academic Search

? PURPOSE: To evaluate the results of combined Intacs (Addition Technology, Fremont, California, USA) and posterior chamber toric implantable Collamer lens (ICLs) (Visian ICL; STAAR Surgical, Monrovia, California, USA) implantation in keratoconic patients with extreme myopia and irregular astigmatism. ? DESIGN: Prospective, single-center, noncomparative, interventional, consecutive case series. ? METHODS: Three eyes of two consecutive highly my- opic keratoconic patients

EFEKAN COSKUNSEVEN; METHIYE ONDER; GEORGE D. KYMIONIS; VASILIOS F. DIAKONIS; EBRU ARSLAN; NIKOLAOS TSIKLIS; DIMITRIOS I. BOUZOUKIS; IOANNIS PALLIKARIS

2007-01-01

184

Information Communication Technology & Crime: the Future of Criminology  

Microsoft Academic Search

Today the 21st century can be considered the centur y of the technological revolution. The increase in communication flows has brought about an evolution in the global economy and the globa l spread of Internet and mobile communication, all of which aff ect our lives significantly and are key factors of social change. New models of deviance and crime can

Arije Antinori

185

30 GHz monolithic balanced mixers using an ion-implanted FET-compatible 3-inch GaAs wafer process technology  

NASA Technical Reports Server (NTRS)

An all ion-implanted Schottky barrier mixer diode which has a cutoff frequency greater than 1000 GHz has been developed. This new device is planar and FET-compatible and employs a projection lithography 3-inch wafer process. A Ka-band monolithic balanced mixer based on this device has been designed, fabricated and tested. A conversion loss of 8 dB has been measured with a LO drive of 10 dBm at 30 GHz.

Bauhahn, P.; Contolatis, A.; Sokolov, V.; Chao, C.

1986-01-01

186

Eff ect of N-( n-butyl) Thiophosphoric Triamide and 3,4 Dimethylpyrazole Phosphate on Gaseous Emissions from Grasslands under Diff erent Soil Water Contents  

Microsoft Academic Search

Th e intensifi cation of grassland systems is leading to serious environmental risks due to the large input of nitrogen (N) in fertilizers and the subsequent gaseous losses. Addition of nitrifi cation inhibitors (NI) or urease activity inhibitors to fertilizers could reduce these losses to the atmosphere. In the present study, the eff ects of the nitrifi cation inhibitor 3,4-dimethylpyrazole

P. Merino; M. Pinto NEIKER

187

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

188

Polo-Like Kinase 1 Directs Assembly of the HsCyk-4 RhoGAP\\/Ect2 RhoGEF Complex to Initiate Cleavage Furrow Formation  

Microsoft Academic Search

Polo-like kinase 1 promotes assembly of the contractile ring that divides a cell in two by creating a docking site for the RhoA activator Ect2 on the Cyk-4-containing centralspindlin complex at the midzone of the mitotic spindle.

Benjamin A. Wolfe; Tohru Takaki; Mark Petronczki; Michael Glotzer

2009-01-01

189

Technology  

Microsoft Academic Search

The presence of technology in the hospitality industry is increasing at a rapid rate. Technology has had an effect on the efficiency of many facets of the hospitality industry. Despite the growing number of meetings, conventions, and conferences, there has not been a published needs assessment study of training needs-especially technology needs-of hospitality sales managers. This paper presents the results

Gail Sammons

2000-01-01

190

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

191

Plasma immersion ion implantation for silicon processing  

NASA Astrophysics Data System (ADS)

Plasma Immersion Ion Implantation (PIII) is a technology which is currently widely investigated as an alternative to conventional beam line implantation for ultrashallow doping beyond the 0.15 m technology. However, there are several other application areas in modern semiconductor processing. In this paper a detailed discussion of the PIII process for semiconductors and of actual as well as future applications is given. Besides the well known advantages of PIII - fast process, implantation of the whole surface, low cost of ownership - several peculiarities - like spread of the implantation energy due to finite rise time or collisions, no mass separation, high secondary electron emission - must be mentioned. However, they can be overcome by adjusting the system and the process parameters. Considering the applications, ultrashallow junction formation by PIII is an established industrial process, whereas SIMOX and Smart-Cut by oxygen and hydrogen implantation are current topics between research and introduction into industry. Further applications of PIII, of which some already are research topics and some are only investigated by conventional ion implantation, include seeding for metal deposition, gettering of metal impurities, etch stop layers and helium implantation for localized lifetime control.

Yankov, Rossen A.; Mändl, Stephan

2001-04-01

192

Ion-implantation doping of silicon carbide  

SciTech Connect

Because of their commercial availability in bulk single crystal form, the 6H- and 4H- polytypes of SiC are gaining importance for high-power, high-temperature, and high-frequency device applications. Selective area doping is a crucial processing step in integrated circuit manufacturing. In Si technology, selective area doping is accomplished by thermal diffusion or ion-implantation. Because of the low diffusion coefficients of most impurities in SiC, ion implantation is indispensable in SiC device manufacturing. In this paper the authors present their results on donor, acceptor, and compensation implants in 6H-SiC.

Gardner, J.; Edwards, A.; Rao, M.V. [George Mason Univ., Fairfax, VA (United States); Papanicolaou, N.; Kelner, G. [Naval Research Lab., Washington, DC (United States); Holland, O.W. [Oak Ridge National Lab., TN (United States)

1997-10-01

193

[Implantable patient chip].  

PubMed

Currently, enormous innovative developments are taking place in the area of micro-electronics. In particular, advances in the sector of chip card controller ICs make it appear possible to quickly implement theoretical applications which, only just a few months ago would have been considered utopian and would have ended up gathering dust in the developer's drawer. The present paper describes a technical possibility, so far not implementable in practice, for always having personal emergency data available. Only a year or two ago any idea of implanting electronic circuitry employing memory modules would have been immediately dropped again. At the present state of development in the area of microelectronics, however, structures measuring less than 5 microns in length have become a matter of routine, and a personal memory chip in biotolerable packaging and measuring no more than about (5 x 5 x 1) mm3 can now be implanted subcutaneously. At the present time, further application based on the use of the same technological facilities, such as, for example, the cyclic recording and storage of the heart rate, are under discussion. PMID:9063953

Bedrich, M R

1996-11-01

194

Implant success!!!.....simplified.  

PubMed

The endeavor towards life-like restoration has helped nurture new vistas in the art and science of implant dentistry. The protocol of "restoration-driven implant placement" ensures that the implant is an apical extension of the ideal future restoration and not the opposite. Meticulous pre-implant evaluation of soft and hard tissues, diagnostic cast and use of aesthetic wax-up and radiographic template combined with surgical template can simplify the intricate roadmap for appropriate implant treatment.By applying the harmony of artistic skill, scientific knowledge and clinical expertise, we can simply master the outstanding implant success in requisites of aesthetics, phonetics and function. PMID:20376237

Luthra, Kaushal K

2009-01-01

195

Technology.  

ERIC Educational Resources Information Center

Presents annotations of 30 works of children's literature that support the topic of technology and its influences on readers' daily lives. Notes some stories tell about a time when simple tools enabled individuals to accomplish tasks, and others feature visionaries who used technology to create buildings, bridges, roads, and inventions. Considers…

Giorgis, Cyndi; Johnson, Nancy J.

2002-01-01

196

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

197

Placing Dental Implants  

MedlinePLUS

... mouth so that no second surgery is needed. Restoration Generally, you will go to your dentist or ... breakage. Either the implant or the implant-supported restoration (crown, bridge or denture) can break. This usually ...

198

Initial stability comparison of modular hip implants in synthetic femurs.  

PubMed

Synthetic femurs were used to assess the initial bone-implant interface stability of three total hip systems: Wright Medical Technology's Infinity smooth trochanteric module (S-TM), Infinity porous-coated trochanteric module (PC-TM), and Johnson and Johnson S-ROM with a porous surface. The hips were implanted into synthetic femurs, rigidly fixed, and subjected to internal rotation and cyclic, axial compressive loads. The results showed that all three implants achieved good initial implant stability and would be expected to permit bone ingrowth. The porous-coated implants showed greater initial implant stability with less axial micromotion compared with the smooth implants. This finding suggests that surface texture plays a role in initial stability of uncemented prostheses if the bone behaves similar to the material used in this study. PMID:9731670

Lee, T Q; Danto, M I; Kim, W C

1998-08-01

199

Physical understanding of cryogenic implant benefits for electrical junction stability  

SciTech Connect

We investigate the effect of cryogenic temperature implants on electrical junction stability for ultra shallow junction applications for sub-32 nm technology nodes and beyond. A comprehensive study was conducted to gain physical understanding of the impact of cryogenic temperature implants on dopant-defect interactions. Carborane (C{sub 2}B{sub 10}H{sub 12}) molecule, a potential alternative to monomer boron was implanted in carbon preamorphized silicon substrates at cryogenic implant temperatures. Results indicate implants at cryogenic temperatures increase dopant activation with reduced diffusion, resulting in lower sheet resistance for a lower junction depth. Further, this study emphasizes the benefits of co-implants performed at cryogenic temperatures as alternative to traditional preamorphizing implants.

Adeni Khaja, Fareen; Colombeau, Benjamin; Thanigaivelan, Thirumal; Ramappa, Deepak; Henry, Todd [Applied Materials-Varian Semiconductor Equipment, 35 Dory Road, Gloucester, Massachusetts 01930 (United States)

2012-03-12

200

Mammography and breast implants  

Microsoft Academic Search

Mammography in the presence of breast implants is complicated by the opacity of the implants, the displacement of breast tissue by the implant, and the presence of secondary changes such as calcification within a fibrous capsule. A special technique of mammography, known as the displacement technique, has been developed by Eklund in the USA, where it is widely used. The

G. L. Bantick; I. Taggart

1995-01-01

201

Clinical utility of implantable loop recorders.  

PubMed

Implantable loop recorders provide the highest sensitivity and accuracy of diagnosing cardiac arrhythmia that results in cardiac syncope. When bradyarrhythmia or tachyarrhythmia, including atrial fibrillation, is detected, appropriate secondary prevention therapy will be implemented, which will impact the long-term clinical outcome. An implantable loop recorder enables the clinician to record for a longer period of time, which increases the likelihood of detecting cardiac arrhythmia. Currently, this technology is being evaluated to diagnose a cardiac etiology of ischemic stroke and to optimize atrial fibrillation management that will predict the success of rhythm control and prevent thromboembolic events. This article reviews implantable loop recorder technology, and discusses the current indications, the outcomes of clinical studies and ongoing current studies, and future technological improvements. PMID:24685966

Houmsse, Mahmoud; Ishola, Abiodun; Daoud, Emile G

2014-03-01

202

The Intergenerational E¤ects of Paternal Migration on Schooling and Work: What Can We Learn from Children’s Time Allocations?  

Microsoft Academic Search

Abstract This paper,explores,the e¤ect of a father’s current,migration,to the U.S. on his children’s schooling,and,work,outcomes,in Mexico.,While remittances,from abroad,could relax the household,budget,constraint and allow the child to obtain,more,schooling,and,work,less they may,be out- weighed,by the deleterious,e¤ects due,to the father’s absence,from,the home,and,the possibility that a father’s migration,experience,could lead to an underinvestment,in Mexican,education,that is not well-rewarded,in the U.S. To get around the endogeneity of paternal migration,

Francisca Antman

203

Parents' narratives on cochlear implantation: reconstructing the experience of having a child with cochlear implant.  

PubMed

This paper discusses parents' narratives on cochlear implantation in Bogotá, Colombia using a qualitative approach. The main research objective was to identify how parents perceived the processes of diagnosis of their child's hearing loss, making the decision for cochlear implantation and the post-surgery period. All participants were hearing couples (n = 13) with similar socio-cultural backgrounds whose children had undergone cochlear implant surgery. Results show why cochlear implants are a very highly valued technological device with great symbolic power for parents. The study also deals with how perceptions about oral/sign language and disability, as well as social expectations for their children's lifetime opportunities, determine how the parents themselves have experienced their journey through the process of their children's cochlear implantation. PMID:21917202

Peñaranda, Augusto; Suárez, Roberto M; Niño, Natalia M; Aparicio, Maria Leonor; García, Juan Manuel; Barón, Clemencia

2011-08-01

204

Deformation and fracture of aluminium foams under proportional and non proportional multi-axial loading: statistical analysis and size e%ect  

Microsoft Academic Search

An extensive experimental programme and detailed mechanical analysis were performed to test and model the statistical response of metallic foams under complexloading conditions. Tensile tests were performed on more than 80 specimens of closed-cell aluminium foams with four di%erent specimen sizes. These test results show a large scatter and a signi7cant size e%ect especially on standard deviation. The average fracture

P.-M. Fourt

205

Eff ects of high-dose versus low-dose losartan on clinical outcomes in patients with heart failure (HEAAL study): a randomised, double-blind trial  

Microsoft Academic Search

Summary Background Angiotensin-receptor blockers (ARBs) are eff ective treatments for patients with heart failure, but the relation between dose and clinical outcomes has not been explored. We compared the eff ects of high-dose versus low-dose losartan on clinical outcomes in patients with heart failure. Methods This double-blind trial was undertaken in 255 sites in 30 countries. 3846 patients with heart

Marvin A Konstam; James D Neaton; Kenneth Dickstein; Helmut Drexler; Michel Komajda; Felipe A Martinez; Gunter A J Riegger

206

[Porous orbital implants].  

PubMed

Since the introduction of the first coralline hydroxyapatite porous orbital implant as eye replacement in the early 1980s, numerous other modified porous implants have been developed. Due to the different design of the existing studies concerning long-term safety with, in some cases, relatively short follow-up, a comparison is difficult and none of the implant types can be clearly identified as being superior. Factors affecting the exposure rate of the implant seem to be the implant coating, the surgical technique and the condition of the patient's tissue at the beginning of surgery. PMID:24942122

Cleres, B; Meyer-Rüsenberg, H W

2014-06-01

207

Nanotechnology Approaches for Better Dental Implants  

PubMed Central

The combined requirements imposed by the enormous scale and overall complexity of designing new implants or complete organ regeneration are well beyond the reach of present technology in many dimensions, including nanoscale, as we do not yet have the basic knowledge required to achieve these goals. The need for a synthetic implant to address multiple physical and biological factors imposes tremendous constraints on the choice of suitable materials. There is a strong belief that nanoscale materials will produce a new generation of implant materials with high efficiency, low cost, and high volume. The nanoscale in materials processing is truly a new frontier. Metallic dental implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel coatings and nanopatterning of dental implants. It also provides a general summary of the state of the art in dental implant science and describes possible advantages of nanotechnology for further improvements. The ultimate goal is to produce materials and therapies that will bring state-of-the-art technology to the bedside and improve quality of life and current standards of care.

Tomsia, Antoni P.; Launey, Maximilien E.; Lee, Janice S.; Mankani, Mahesh H.; Wegst, Ulrike G.K.; Saiz, Eduardo

2011-01-01

208

Peri-implant soft tissue management: Where are we?  

PubMed Central

Dental implants have evolved dramatically over the last decade, and so have our expectations from them in terms of functional and esthetic criteria. The maintenance and augmentation of the soft tissue has emerged as an area of concern and focus. The triad of anatomical peri-implant characteristics, soft tissue response to the implant material, and clinical skill form the fundamental principles in augmenting soft tissue. However, as clinicians, where are we with regards to the ability to augment and maintain soft tissue around dental implants, about 40 years after the first implants were placed? We now understand that peri-implant soft tissue management begins with extraction management. Our treatment modalities have evolved from socket compression post-extraction, to socket preservation with an aim to enhance the eventual peri-implant soft tissue. This short communication will assess the evolution of our thought regarding peri-implant soft tissue management, augmentation of keratinized mucosa around implants, and also look at some recent techniques including the rotated pedicle connective tissue graft for enhancing inter-implant papilla architecture. With newer research modalities, such as cyto-detachment technology, and cutting-edge bioengineering solutions (possibly a soft-tissue-implant construct) which might be available in the near future for enhancing soft tissue, we are certainly in an exciting era in dentistry.

Bhatavadekar, Neel

2012-01-01

209

Peri-implant soft tissue management: Where are we?  

PubMed

Dental implants have evolved dramatically over the last decade, and so have our expectations from them in terms of functional and esthetic criteria. The maintenance and augmentation of the soft tissue has emerged as an area of concern and focus. The triad of anatomical peri-implant characteristics, soft tissue response to the implant material, and clinical skill form the fundamental principles in augmenting soft tissue. However, as clinicians, where are we with regards to the ability to augment and maintain soft tissue around dental implants, about 40 years after the first implants were placed? We now understand that peri-implant soft tissue management begins with extraction management. Our treatment modalities have evolved from socket compression post-extraction, to socket preservation with an aim to enhance the eventual peri-implant soft tissue. This short communication will assess the evolution of our thought regarding peri-implant soft tissue management, augmentation of keratinized mucosa around implants, and also look at some recent techniques including the rotated pedicle connective tissue graft for enhancing inter-implant papilla architecture. With newer research modalities, such as cyto-detachment technology, and cutting-edge bioengineering solutions (possibly a soft-tissue-implant construct) which might be available in the near future for enhancing soft tissue, we are certainly in an exciting era in dentistry. PMID:23493178

Bhatavadekar, Neel

2012-10-01

210

Peri-implantitis.  

PubMed

The risk of developing peri-implantitis seems to be more pronounced in patients with a history of periodontitis. Pretreatment to eliminate periodontal pathogens from the patient's oral cavity before dental implant treatment therefore is important to reduce the risk of peri-implantitis. Smoking has been shown to be a negative risk factor for treatment success. Several protocols have been used in the treatment of peri-implantitis. Mechanical infection control following surgical flap procedures, particularly in conjunction with antimicrobial therapy, is the most successful concept. There is no reliable evidence that suggests which intervention is the most effective for treating peri-implantitis. This article includes background information on the biology of tissue-destructive periodontitis and peri-implantitis to help clinicians interpret the clinical manifestation of the risk for peri-implantitis. PMID:15978246

Klinge, Björn; Hultin, Margareta; Berglundh, Tord

2005-07-01

211

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

2011-04-01

212

Emerging synergy between nanotechnology and implantable biosensors: A review  

Microsoft Academic Search

The development of implantable biosensors for continuous monitoring of metabolites is an area of sustained scientific and technological interests. 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

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

2010-01-01

213

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.

Lavenus, Sandrine; Louarn, Guy; Layrolle, Pierre

2010-01-01

214

Finite volume analysis of temperature effects induced by active MRI implants: 2. Defects on active MRI implants causing hot spots  

Microsoft Academic Search

BACKGROUND: Active magnetic resonance imaging implants, for example stents, stent grafts or vena cava filters, are constructed as wireless inductively coupled transmit and receive coils. They are built as a resonator tuned to the Larmor frequency of a magnetic resonance system. The resonator can be added to or incorporated within the implant. This technology can counteract the shielding caused by

Martin HJ Busch; Wolfgang Vollmann; Dietrich HW Grönemeyer

2006-01-01

215

Incidence of Endodontic Implantitis and Implant Endodontitis Occurring with Single-tooth Implants: A Retrospective Study  

Microsoft Academic Search

The purposes of this study were to determine success and survival rates for implants and teeth adjacent to implants and the incidence of endodontic implantitis (E-I) (endodontic involvement in adjacent teeth causing implant failure) and implant endodontitis (I-E) (implant placement causing endodontic failure). The data were from 233 single-tooth implants placed in 116 subjects by postgraduate periodontal students with recall

Bradley S. Laird; Michael S. Hermsen; Tom G. Gound; Fahd Al Salleeh; Matthew R. Byarlay; Merlyn Vogt; David B. Marx

2008-01-01

216

Kelch-like ECT2-interacting protein KLEIP regulates late-stage pulmonary maturation via Hif-2? in mice  

PubMed Central

Respiratory distress syndrome (RDS) caused by preterm delivery is a major clinical problem with limited mechanistic insight. Late-stage embryonic lung development is driven by hypoxia and the hypoxia-inducible transcription factors Hif-1? and Hif-2?, which act as important regulators for lung development. Expression of the BTB-and kelch-domain-containing (BTB-kelch) protein KLEIP (Kelch-like ECT2-interacting protein; also named Klhl20) is controlled by two hypoxia response elements, and KLEIP regulates stabilization and transcriptional activation of Hif-2?. Based on the available data, we hypothesized an essential role for KLEIP in murine lung development and function. Therefore, we have performed a functional, histological, mechanistic and interventional study in embryonic and neonatal KLEIP?/? mice. Here, we show that about half of the KLEIP?/? neonates die due to respiratory failure that is caused by insufficient aeration, reduced septal thinning, reduced glycogenolysis, type II pneumocyte immaturity and reduced surfactant production. Expression analyses in embryonic day (E) 18.5 lungs identified KLEIP in lung capillaries, and showed strongly reduced mRNA and protein levels for Hif-2? and VEGF; such reduced levels are associated with embryonic endothelial cell apoptosis and lung bleedings. Betamethasone injection in pregnant females prevented respiratory failure in KLEIP?/? neonates, normalized lung maturation, vascularization, aeration and function, and increased neonatal Hif-2? expression. Thus, the experimental study shows that respiratory failure in KLEIP?/? neonates is determined by insufficient angiocrine Hif-2?–VEGF signaling and that betamethasone activates this newly identified signaling cascade in late-stage embryonic lung development.

Woik, Nicole; Dietz, Christian T.; Schaker, Kathrin; Kroll, Jens

2014-01-01

217

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.

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

2012-01-01

218

UWB for low power, short range, in-body medical implants  

Microsoft Academic Search

Medical implants are battery-powered, and have very stringent power consumption requirements. Devices like pacemakers consume few tens of microamps and last for well over 7-8 years. RF technologies are increasingly enabling communication and configuration of these medical implants. The Federal Communications Commission (FCC) has allocated a dedicated spectrum for operation of medical devices, the Medical Implant Communication System (MICS). This

Ashutosh Ghildiyal; Balwant Godara; Karima Amara; Renzo Dalmolin; Amara Amara

2010-01-01

219

Study of low energy implants for ultrashallow junctions using thermal wave and optical techniques  

NASA Astrophysics Data System (ADS)

A combination of the thermal wave and optical technologies was found to be advantageous in characterization of implants for ultrashallow junctions. Two sets of Si wafers implanted with boron and arsenic ions at low energies (0.5-5.0 keV) and high dose (5×1014 cm-2) were studied after implantation and prior to annealing. Signals obtained by using the thermal wave and optical methods exhibit a linear dependence on implantation energy below 2 keV for both implants. Results of the thermal wave and optical studies were also correlated to conventional TRIM calculations of crystalline damage and implanted ion concentration.

Nicolaides, Lena; Salnick, Alex; Opsal, Jon

2003-01-01

220

Larynx: implants and stents.  

PubMed

In the human larynx, implants a primarily used for the correction of glottis insufficiency. In a broader sense laryngeal stents may be considered as implants as well. Laryngeal implants can be differentiated into injectable and solid. The most important representatives of both groups are discussed in detail along with the respective technique of application. Laryngeal stents are primarily used perioperatively. Different types and their use are presented. PMID:22073097

Sittel, Christian

2009-01-01

221

Larynx: implants and stents  

PubMed Central

In the human larynx, implants a primarily used for the correction of glottis insufficiency. In a broader sense laryngeal stents may be considered as implants as well. Laryngeal implants can be differentiated into injectable and solid. The most important representatives of both groups are discussed in detail along with the respective technique of application. Laryngeal stents are primarily used perioperatively. Different types and their use are presented.

Sittel, Christian

2011-01-01

222

Implantable cardioverter defibrillator during laser transurethral resection of the prostate.  

PubMed

  Implantable cardioverter defibrillators have been instrumental in the health and safety of patients who are at increased risk of sudden death by ventricular tachycardia or fibrillation. Consensus on the perioperative management of cardiovascular implantable electronic devices has suggested that certain surgical interventions (including transurethral resection of the prostate) may interfere with the sensing capability of the device, thereby resulting in unforeseen adverse outcomes. However, improvements in the implantable cardioverter defibrillators have made it less susceptible to surgical interference. In addition, current guidelines recommend deactivation of the implantable cardioverter defibrillators to an asynchronous mode prior to most surgical interventions. We present the first two case reports in which implantable cardioverter defibrillators were not deactivated prior to GreenLight 180-W XPS laser-guided transurethral resection of the prostate. We left the implantable cardioverter defibrillators activated to allow them to detect and treat lethal arrhythmias by direct rather than extrinsic cardioversion. There was no cardiac arrhythmia incident in these two cases. Laser technology is not a documented source of electromagnetic interference in patients with implantable cardioverter defibrillators. There is no current evidence that links lasers to implantable cardioverter defibrillators malfunction. With increasing numbers of patients with implantable cardioverter defibrillators undergoing many different laser surgical procedures, further studies are warranted to analyze in depth the effects of laser therapy on implantable cardioverter defibrillators function and update in current guidelines. PMID:24800199

Deroee, A F; Cohen, B J; O'Hara, J F

2014-01-01

223

History of implants.  

PubMed

In summary, implants are highly successful because encapsulation occurs around the implant without rejection and no other fixation is necessary. There is relatively no shortening or instability of the toe, such as a floppy toe. This seems to prevent painful stiff pseudoarthrosis or arthritis because it acts as a spacer to prevent narrowing of the joint and allows for movement. It prevents a short first toe and prevents any undesired cosmetic results, as it provides the joint with a pain-free range of motion, allowing it to become more mobile and stable. Also, ulnar implants have been used with the same indications and contraindications. The most important consideration about implant surgery is that these implants, that is, the Silastic and the Swanson design, are nonabsorbable. They will not cause tissue reaction and the fibrous encapsulation forms all that is necessary to encapsulate the implant itself; therefore, there is very little bony rejection. From recent literature and through professional experience, it has been proved that implants act primarily as a spacer. They provide a pain-free range of motion but not as well as desired. Implants provide stability to the joint, which is of the utmost importance. The Silastic implants have stood the test of time in most cases. However, the search for better biomaterials, better results, and better functions is never ending. There is a great need for continued research into this field. Podiatry must continue to maintain, contribute, and improve this research. PMID:6399227

Kaplan, E G; Kaplan, G S; Kaplan, D M; Kaplan, R K

1984-04-01

224

Complications in implant dentistry.  

PubMed

The mainstream use of dental implants has allowed millions of patients to benefit from the predictability of dental implant therapy and, in many instances, dental implants have become the standard of care. Even though success rates in implant dentistry are well above 90 percent, complications do occur. Most complications are preventable with proper planning and execution. Others are inherent to the risks of surgery and may require intervention. The purpose of this paper is to classify the possible complications that may occur and to discuss their prevention and management. PMID:24881442

Pi-Anfruns, Joan

2014-01-01

225

LINAC simulation for high energy ion implantation  

Microsoft Academic Search

RF linear accelerators (LINACs) are routinely used to accelerate ions to few hundreds of MeV in high energy physics accelerators. When this technology is applied to high energy ion implantation for semiconductor device fabrication, parameters such as high transmission, low energy spread, and small beam emittance must be preserved over a wide range of energies and masses. We have modified

Z. Wan; K. Saadatmand; F. Sinclair; W. Lysenko; B. Rusnak; L. Young

1996-01-01

226

Fully ion-implanted bipolar transistors  

Microsoft Academic Search

Technology for the fabrication of fully ion-implanted bipolar transistors with arsenic emitters and boron bases is described. This technology results in extremely uniform distributions of electrical parameters, e.g,, hFE= 113 with a standard deviation of 1.3 across a wafer. In addition, it can produce a wide range of doping profiles and hence, a wide range of device performance. Using very

R. S. Payne; R. J. Scavuzzo; K. H. Olson; J. M. Nacci; R. A. Moline

1974-01-01

227

Orchestrated Regulation of Nogo Receptors, Lotus, AMPA Receptors and BDNF in an ECT Model Suggests Opening and Closure of a Window of Synaptic Plasticity  

PubMed Central

Electroconvulsive therapy (ECT) is an efficient and relatively fast acting treatment for depression. However, one severe side effect of the treatment is retrograde amnesia, which in certain cases can be long-term. The mechanisms behind the antidepressant effect and the amnesia are not well understood. We hypothesized that ECT causes transient downregulation of key molecules needed to stabilize synaptic structure and to prevent Ca2+ influx, and a simultaneous increase in neurotrophic factors, thus providing a short time window of increased structural synaptic plasticity. Here we followed regulation of NgR1, NgR3, LOTUS, BDNF, and AMPA subunits GluR1 and GluR2 flip and flop mRNA levels in hippocampus at 2, 4, 12, 24, and 72 hours after a single episode of induced electroconvulsive seizures (ECS) in rats. NgR1 and LOTUS mRNA levels were transiently downregulated in the dentate gyrus 2, 4, 12 and 4, 12, 24 h after ECS treatment, respectively. GluR2 flip, flop and GluR1 flop were downregulated at 4 h. GluR2 flip remained downregulated at 12 h. In contrast, BDNF, NgR3 and GluR1 flip mRNA levels were upregulated. Thus, ECS treatment induces a transient regulation of factors important for neuronal plasticity. Our data provide correlations between ECS treatment and molecular events compatible with the hypothesis that both effects and side effects of ECT may be caused by structural synaptic rearrangements.

Nordgren, Max; Karlsson, Tobias; Svensson, Maria; Koczy, Josefin; Josephson, Anna; Olson, Lars; Tingstrom, Anders; Brene, Stefan

2013-01-01

228

CUX1 and E2F1 Regulate Coordinated Expression of the Mitotic Complex Genes Ect2, MgcRacGAP, and MKLP1 in S Phase ? †  

PubMed Central

Rho GTPases are critical for mitosis progression and completion of cytokinesis. During mitosis, the GDP/GTP cycle of Rho GTPases is regulated by the exchange factor Ect2 and the GTPase activating protein MgcRacGAP which associates with the kinesin MKLP1 in the centralspindlin complex. We report here that expression of Ect2, MgcRacGAP, and MKLP1 is tightly regulated during cell cycle progression. These three genes share similar cell cycle-related signatures within their promoter regions: (i) cell cycle gene homology region (CHR) sites located at ?20 to +40 nucleotides of their transcription start sites that are required for repression in G1, (ii) E2F binding elements, and (iii) tandem repeats of target sequences for the CUX1 transcription factor. CUX1 and E2F1 bind these three promoters upon S-phase entry, as demonstrated by chromatin immunoprecipitation, and regulate transcription of these genes, as established using promoter-luciferase reporter constructs and expression of activated or dominant negative transcription factors. Overexpression of either E2F1 or CUX1 increased the levels of the endogenous proteins whereas small interfering RNA knockdown of E2F1 or use of a dominant negative E2F1 reduced their expression levels. Thus, CUX1, E2F, and CHR elements provide the transcriptional controls that coordinate induction of Ect2, MgcRacGAP, and MKLP1 in S phase, leading to peak expression of these interacting proteins in G2/M, at the time they are required to regulate cytokinesis.

Seguin, Laetitia; Liot, Caroline; Mzali, Rym; Harada, Ryoko; Siret, Aurelie; Nepveu, Alain; Bertoglio, Jacques

2009-01-01

229

Quantitative Ion Implantation.  

National Technical Information Service (NTIS)

This is a report of the study of the implantation of heavy ions at medium keV-energies into electrically conducting mono-elemental solids, at ion doses too small to cause significant loss of the implanted ions by resputtering. The study has been undertake...

W. H. Gries

1976-01-01

230

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

231

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

232

Breast Implants: An Information Guide, 1998.  

National Technical Information Service (NTIS)

Contents: Background; Availability of Implants; The Surgery; Surgical Risks of Implants; Other Implant-Related Risks; Illness and Conditions Elsewhere in the Body and Breast Implants; Special Medical and Physical Considerations; Breast Implants and Medica...

1998-01-01

233

Corticosteroid intravitreal implants.  

PubMed

Intraocular implants developed for ocular inflammation which release glucocorticoids for a prolonged period within the vitreous cavity make use of either a bioerodible polymer (dexamethasone in polylactic acid-coglycolic acid matrix) or non-erodible implantable device (fluocinolone acetonide, FA, in a polyvinyl acetate/silicone laminate). Pharmacologically, both steroids are similar in their binding characteristics to glucocorticoid receptors (GR), their ability to transactivate the GR complex and their vitreous half-lives. They both possess neuroprotective properties for retina and retinal pigment epithelium which place them apart from triamcinolone acetonide. Triamcinolone acetonide's higher lipophilicity makes it possible to create an implant with prolonged release characteristics, but may be increasing the propensity for ocular side effects such as cataract and glaucoma. In clinical trials, both implants were shown to be effective at inhibiting intraocular inflammation in patients with intermediate or posterior uveitis. The Dexamethasone implant is inserted through a 22-gauge needle through the pars plana and can control inflammation for up to 6 months. The FA implant requires surgical insertion through the pars plana and can control inflammation for up to 3 years. The MUST trial has shown the FA implant when placed bilaterally to be slightly more effective than strict systemic therapy, though at the cost of additional ocular surgeries for cataract and glaucoma. Certain clinical situations particularly with asymmetric uveitis may in fact favor local vs. systemic therapy. PMID:22517210

de Smet, Marc D

2012-01-01

234

Dental implants from functionally graded materials.  

PubMed

Functionally graded material (FGM) is a heterogeneous composite material including a number of constituents that exhibit a compositional gradient from one surface of the material to the other subsequently, resulting in a material with continuously varying properties in the thickness direction. FGMs are gaining attention for biomedical applications, especially for implants, owing to their reported superior composition. Dental implants can be functionally graded to create an optimized mechanical behavior and achieve the intended biocompatibility and osseointegration improvement. This review presents a comprehensive summary of biomaterials and manufacturing techniques researchers employ throughout the world. Generally, FGM and FGM porous biomaterials are more difficult to fabricate than uniform or homogenous biomaterials. Therefore, our discussion is intended to give the readers about successful and obstacles fabrication of FGM and porous FGM in dental implants that will bring state-of-the-art technology to the bedside and develop quality of life and present standards of care. PMID:23754641

Mehrali, Mehdi; Shirazi, Farid Seyed; Mehrali, Mohammad; Metselaar, Hendrik Simon Cornelis; Kadri, Nahrizul Adib Bin; Osman, Noor Azuan Abu

2013-10-01

235

Plasma-based biofunctionalization of vascular implants.  

PubMed

Polymeric and metallic materials are used extensively in permanently implanted cardiovascular devices and devices that make temporary but often prolonged contact with body fluids and tissues. Foreign body responses are typically triggered by host interactions at the implant surface, making surface modifications to increase biointegration desirable. Plasma-based treatments are extensively used to modify diverse substrates; modulating surface chemistry, wettability and surface roughness, as well as facilitating covalent biomolecule binding. Each aspect impacts on facets of vascular compatibility including endothelialization and blood contact. These modifications can be readily applied to polymers such as Dacron and expanded polytetrafluoroethylene, which are widely used in bypass grafting and the metallic substrates of stents, valves and pacemaker components. Plasma modification of metals is more challenging given the need for coating deposition in addition to surface activation, adding the necessity for robust interface adhesion. This review examines the evolving plasma treatment technology facilitating the biofunctionalization of polymeric and metallic implantable cardiovascular materials. PMID:23249334

Wise, Steven G; Waterhouse, Anna; Kondyurin, Alexey; Bilek, Marcela M; Weiss, Anthony S

2012-12-01

236

Analyses of fractured implant fixture after prolonged implantation  

Microsoft Academic Search

Although fortunately rare, fracture of implants causes significant problems for both clinicians and patients. The major cause\\u000a of a fractured implant may be corrosion fatigue fracture. To investigate how to increase the fatigue life and corrosion resistance\\u000a of dental implants, the surface morphology of six Steri-Oss fractured implants was analyzed. The period of implantation after\\u000a loading in patient jaws varied

Han-Cheol Choe; June-Kyu Lee; Chae-Heon Chung

2004-01-01

237

The contraceptive implant.  

PubMed

Contraceptive implants provide long-acting, highly effective reversible contraception. Currently, the only subdermal implant available to women in the United States is the single rod etonogestrel implant, Implanon (N.V. Organon, Oss, the Netherlands) approved by the Food and Drug Administration in July 2006. Implanon is currently approved for 3 years of use, provides excellent efficacy throughout its use, and is easy to insert and remove. Similar to other progestin-only contraceptives, Implanon can cause irregular vaginal bleeding. Implanon has been shown to be safe to use during lactation, may improve dysmenorrhea, and does not significantly affect bone mineral density, lipid profile, or liver enzymes. PMID:17982333

Hohmann, Heather; Creinin, Mitchell D

2007-12-01

238

Spectroscopy of implants  

NASA Astrophysics Data System (ADS)

The spectral criteria of selection of soft intraocular lens (IOL) implants of long service in an organism have been defined for ophthalmology. The analysis of Fourier Transform Infrared (FTIR) spectra provides the required and sufficient level of material polymerization for manufacturing non-toxic lenses for the eye. The spectral limits for determining the biocompatibility of samples can be related to the intensity ratio of two bands only in the FTIR spectra of siloxane. Siloxane-poly(urethane) block copolymers and other materials for implants have been studied. Passivated surfaces of implants have been obtained and registered by methods of Fourier Transform Spectroscopy.

Afanasyeva, Natalia I.

1994-01-01

239

Dynamic Ion Implantation.  

NASA Astrophysics Data System (ADS)

The Dynamic Ion Implantation Technique consists of ion implantation of a film during the film deposition process. This technique was investigated theoretically and experimentally with ions whose incident energy is of the order of a few times 100 keV. We found it to be a viable alternative low-temperature method for the preparation of thick zirconium nitride films (~1 ?m) with good mechanical properties. Theoretical modeling of the processes involved during dynamic ion implantation lead to analytical expressions for the ions' depth profile distributions. Numerical evaluations of these equations indicated that the depth distributions of dynamically implanted ions are in general more uniform than those predicted by the model for ions implanted by more conventional techniques like, for example, the post implantation technique. Theoretical and experimental profiles were found to be in reasonable agreement. Numerical evaluations of analytical expressions obtained with a diffusional model of the dynamic ion beam mixing pointed out the possibility of tailoring the amounts of induced mixing in order to suit experimental needs. Rutherford Backscattering Spectroscopy and Grazing Angle X-Ray Diffraction analysis indicated zirconium nitride phase formation in RF sputter deposited zirconium films (~ 5000 A) dynamically implanted with singly ionized molecular nitrogen, for ion to atom arrival ratios of the order of 0.44, and 100 keV ion incident energy. Knoop micro-hardness of samples, prepared with nitrogen to zirconium arrival ratios ranging from 0.027 to 0.44 and ion incident energies between 100 and 300 keV, were found to increase with increasing ion to atom arrival ratios and decrease with increasing energies. Mechanical properties of stoichiometric RF sputter deposited zirconium nitride films post implanted with krypton and rubidium ions were investigated. Scratch-adhesion critical load and Vickers micro-hardness of samples implanted with doses varying from 1 times 10 ^{15} to 5 times 10^{16} ions/cm ^2 and energies ranging from 300 to 500 keV were studied. In general, best mechanical properties were observed for 300-keV krypton implantations. At this energy and an implanted dose of 1 times 10^{15} ion/cm ^2, an increment of the order of 60% in micro -hardness was obtained for the implanted sample with respect to the as-deposited sample.

Oppenheim, Ivette F. C.

240

Annealing of PEEK, PET and PI implanted with Co ions at high fluencies  

NASA Astrophysics Data System (ADS)

The properties of implanted polymers strongly depend on the implantation ion fluence and on the properties of the implanted atoms. The stability of synthesized nano-structures during further technological steps like annealing is of importance for their possible applications. Polyimide (PI), polyetheretherketone (PEEK), and polyethyleneterephtalate (PET) were implanted with 40 keV Co+ ions at room temperature at fluences ranging from 0.2 × 1016 cm-2 to 1.0 × 1017 cm-2 and annealed at a temperature of 200 °C. The implanted depth profiles of as-implanted and annealed samples, determined by the RBS method, were compared with the results of SRIM 2012 simulations. The structural and compositional changes of the implanted and subsequently annealed polymers were characterized by RBS and UV-vis spectroscopy. The surface morphology of as-implanted and annealed samples was examined by the AFM method and their electrical properties by sheet resistance measurement.

Mackova, A.; Malinsky, P.; Miksova, R.; Pupikova, H.; Khaibullin, R. I.; Valeev, V. F.; Svorcik, V.; Slepicka, P.

2013-07-01

241

Modular adaptive implant based on smart materials.  

PubMed

Applications of biological methods and systems found in nature to the study and design of engineering systems and modern technology are defined as Bionics. The present paper describes a bionics application of shape memory alloy in construction of orthopedic implant. The main idea of this paper is related to design modular adaptive implants for fractured bones. In order to target the efficiency of medical treatment, the implant has to protect the fractured bone, for the healing period, undertaking much as is possible from the daily usual load of the healthy bones. After a particular stage of healing period is passed, using implant modularity, the load is gradually transferred to bone, assuring in this manner a gradually recover of bone function. The adaptability of this design is related to medical possibility of the physician to made the implant to correspond to patient specifically anatomy. Using a CT realistic numerical bone models, the mechanical simulation of different types of loading of the fractured bones treated with conventional method are presented. The results are commented and conclusions are formulated. PMID:19050799

Bîzdoac?, N; Tarni??, Daniela; Tarni??, D N

2008-01-01

242

Anomalous Current-Voltage Characteristics and Threshold Voltage Shift in Implanted-Polysilicon-Gated Complementary MetalOxideSemiconductor Field-Effect Transistors with\\/without Titanium-Polycide Technology  

Microsoft Academic Search

The current-voltage (I-V) characteristics and threshold voltage (V t) of implanted-polycrystalline surface channel complementary metal-oxide-semiconductor field-effect transistors (CMOSFETs) with and without titanium-polycided polycrystalline silicon gate structures are compared. We find that the earlier punch-through phenomenon is caused by boron (B) penetration into the gate oxide and channel regions in the boron-implanted p+-poly-silicon-gated device, and this degradation is reduced by using

Chii-Wen Chen; Yean-Kuen Fang; Gun-Yuan Lee; Jang-Cheng Hsieh; Mong-Song Liang; Mou-Shiung Lin; Chue-San Yoo

1995-01-01

243

Cochlear Implantation after Kidney Transplantation  

PubMed Central

Patients with chronic renal failure may develop sensorineural hearing loss. Cochlear implantation has rarely done after organ transplantation. Herein, we report on a 33-year-old kidney transplantation recipient who underwent cochlear implantation for her progressive sensorineural hearing loss in Khalili Hospital Cochlear Implant Center, affiliated to Shiraz University of Medical Sciences. The implantation was done successfully with no complications. Cochlear implantation may be an appropriate therapeutic option for sensorineural hearing loss caused by chronic renal failure.

Hashemi, S. B.; Bahrani Fard, H.; Zandifar, Z.

2012-01-01

244

Implantable Insulin Delivery System.  

National Technical Information Service (NTIS)

An insulin delivery system suitable for experimental implants and external use has been developed to study glucose control for diabetics. The programmable system developed at Sandia National Laboratories, in conjunction with the University of New Mexico S...

J. T. Love J. I. Gaona

1981-01-01

245

Single-Tooth Implants  

MedlinePLUS

... a crown. The final crown in place The restoration (the part that looks like a tooth) is ... has had advanced training in the placement and restoration of implants. Your dentist will do a comprehensive ...

246

Implant-Supported Bridge  

MedlinePLUS

... dental lab. Porcelain-fused-to-metal bridge The restoration (the part that looks like teeth) is a ... who has advanced training in the placement and restoration of implants. Your dentist will do a comprehensive ...

247

Elementary Implantable Force Sensor  

PubMed Central

Implementing implantable sensors which are robust enough to maintain long term functionality inside the body remains a significant challenge. The ideal implantable sensing system is one which is simple and robust; free from batteries, telemetry, and complex electronics. We have developed an elementary implantable sensor for orthopaedic smart implants. The sensor requires no telemetry and no batteries to communicate wirelessly. It has no on-board signal conditioning electronics. The sensor itself has no electrical connections and thus does not require a hermetic package. The sensor is an elementary L-C resonator which can function as a simple force transducer by using a solid dielectric material of known stiffness between two parallel Archimedean coils. The operating characteristics of the sensors are predicted using a simplified, lumped circuit model. We have demonstrated sensor functionality both in air and in saline. Our preliminary data indicate that the sensor can be reasonably well modeled as a lumped circuit to predict its response to loading.

Wachs, Rebecca A.; Ellstein, David; Drazan, John; Healey, Colleen P.; Uhl, Richard L.; Connor, Kenneth A.

2014-01-01

248

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

249

Knee Replacement Implants  

MedlinePLUS

... and 20 ounces, depending on the size selected. Material Criteria The construction materials used must meet several criteria: They must be ... for fixation. Cementless implants are made of a material that attracts new bone growth. Most are textured ...

250

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

251

NEAMTWS-ECTE1: The First Enlarged Communication Test Exercise of the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and connected seas  

NASA Astrophysics Data System (ADS)

During the seventh session of the Intergovernmental Coordination Group for the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and connected seas (ICG/NEAMTWS) held in Paris, France, from 23 to 25 November 2010, a task team on Communication Test and Tsunami Exercises (TT-CT&TE) was established. The task team was responsible for the preparation and conduct of the First Enlarged Communication Test Exercise (NEAMTWS-ECTE1) and the organization of its assessment. The aim of the test exercise was to refine procedures for testing the communication of tsunami alert messages between National Tsunami Warning Centres and all Tsunami Warning Focal Points (TWFPs), including speed and availability within NEAM region. Earlier small size tests, conducted during the previous intersessional period, highlighted the importance of having other communication method like Global Telecommunication System (GTS), and therefore the utilization of GTS during the NEAMTWS-ECTE1 was another aim of the exercise. NEAMTWS-ECTE1 was conducted on 10 August 2011 with the participation of 139 end-users belonging to 42 agencies in 31 countries. A methodical and detailed analysis of the ECTE1 has been provided to ICG/NEAMTWS as a report, where 27 new recommendations were provided in order to improve all aspects of a Communication Test Exercise (CTE), ranging from the manual to the interaction with the media, but especially focusing on the technical and procedural improvements. Some technical problems during the NEAMTWS-ECTE1 have helped to clearly identify certain operational and procedural issues on which NEAMTWS should conclude some guidelines. A Small Scale Communication Test (SSCT-1) focusing on the problem areas of NEAMTWS-ECTE1 was conducted on 26 October 2011 as a follow-up exercise to consolidate the lessons learnt from NEAMTWS-ECTE1. Both NEAMTWS-ECTE-1 and SSCT-1 clearly indicates that message dissemination using fax is the least effective communication method utilized and subject to deficiencies beyond the control of the message provider and/or recipient. GTS dissemination should be considered as very effective, yet more testing needs to be done to obtain a sufficient maturity of the use of GTS within NEAM region.

Necmioglu, O.; Rudloff, A.; Matias, L. M.; Schindele, F.; Comoglu, M.; Meral Ozel, N.

2012-04-01

252

Ion implantation effects on GaAs MESFET's  

NASA Astrophysics Data System (ADS)

The effects of ion-implantation on the uniformity and the ultimately achievable performance of GaAs MESFETs are calculated. The results of an extensive study of the profiles of Si, Se, and Be ions implanted into GaAs are incorporated into a combined process and device model for GaAs MESFET technology. Taken into account are the scaling of transconductances with implantation energy, effects of implant profile and impurities on low-gate-bias transconductances, dopant diffusion during annealing, effects of encapsulant thickness and etch depth on threshold-voltage uniformity, and effects of recoil atoms on threshold voltages for implants through Si3N4 and SiO2 caps.

Anholt, Robert; Sigmon, Thomas W.

1989-02-01

253

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.

Elkarargy, Amr

2014-01-01

254

Biomaterials in cochlear implants  

PubMed Central

The cochlear implant (CI) represents, for almost 25 years now, the gold standard in the treatment of children born deaf and for postlingually deafened adults. These devices thus constitute the greatest success story in the field of ‘neurobionic’ prostheses. Their (now routine) fitting in adults, and especially in young children and even babies, places exacting demands on these implants, particularly with regard to the biocompatibility of a CI’s surface components. Furthermore, certain parts of the implant face considerable mechanical challenges, such as the need for the electrode array to be flexible and resistant to breakage, and for the implant casing to be able to withstand external forces. As these implants are in the immediate vicinity of the middle-ear mucosa and of the junction to the perilymph of the cochlea, the risk exists – at least in principle – that bacteria may spread along the electrode array into the cochlea. The wide-ranging requirements made of the CI in terms of biocompatibility and the electrode mechanism mean that there is still further scope – despite the fact that CIs are already technically highly sophisticated – for ongoing improvements to the properties of these implants and their constituent materials, thus enhancing the effectiveness of these devices. This paper will therefore discuss fundamental material aspects of CIs as well as the potential for their future development.

Stover, Timo; Lenarz, Thomas

2011-01-01

255

Infection in breast implants.  

PubMed

Infection is the leading cause of morbidity that occurs after breast implantation and complicates 2.0-2.5% of interventions in most case series. Two-thirds of infections develop within the acute post-operative period, whereas some infections may develop years or even decades after surgery. Infection rates are higher after breast reconstruction and subsequent implantation than after breast augmentation. Risk factors for infection associated with breast implantation have not been carefully assessed in prospective studies with long-term follow-up. Surgical technique and the patient's underlying condition are the most important determinants. In particular, breast reconstruction after mastectomy and radiotherapy for cancer is associated with a higher risk for infection. The origin of infection in women with implants remains difficult to determine, but potential sources include a contaminated implant, contaminated saline, the surgery itself or the surgical environment, the patient's skin or mammary ducts, or, as suggested by many reports, seeding of the implant from remote infection sites. Late infection usually results from secondary bacteraemia or an invasive procedure at a location other than breasts. Diagnostic and management strategies are proposed and the value of peri-operative surgical prophylaxis is revisited. The current hypothesis of the possible role of low-grade or subclinical infection in the origin of capsular contracture is also reviewed. PMID:15680779

Pittet, Brigitte; Montandon, Denys; Pittet, Didier

2005-02-01

256

Synthesis of CAD\\/CAM, robotics and biomaterial implant fabrication: single-step reconstruction in computer aided frontotemporal bone resection  

Microsoft Academic Search

The preoperative manufacturing of individual skull implants, developed by an interdisciplinary research group at Ruhr-University Bochum, is based on the use of titanium as the most common material for implants at present. Using the existing technology for materials that can be milled or moulded, customized implants may be manufactured as well. The goal of the study was to examine biodegradable

Stephan Weihe; Michael Wehmöller; Henning Schliephake; Stefan Haßfeld; Alexander Tschakaloff; Jörg Raczkowsky; Harald Eufinger

2000-01-01

257

Modulation techniques for biomedical implanted devices and their challenges.  

PubMed

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

258

Laser Additive Manufacturing of Modified Implant Surfaces with Osseointegrative Characteristics  

NASA Astrophysics Data System (ADS)

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 a curved surface, process constraints for single lattice bars are studied. The investigated lattice structure was thereupon applied on the surface of a medical implant.

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

259

Nanostructured ceramics for biomedical implants.  

PubMed

Recent progress in the synthesis, characterization, and biological compatibility of nanostructured ceramics for biomedical implants is reviewed. A major goal is to develop ceramic coating technology that can reduce the friction and wear in mating total joint replacement components, thus contributing to their significantly improved function and longer life span. Particular attention is focused on the enhancement of mechanical properties such as hardness, toughness, and friction coefficient and on the bioactivity as they pertain to the nanostructure of the material. The development of three nanostructured implant coatings is discussed: diamond, hydroxyapatite, and functionally graded metalloceramics based on the Cr-Ti-N ternary system. Nanostructured diamond produced by chemical vapor deposition (CVD) techniques and composed of nano-size diamond grains have particular promise because of the combination of ultrahigh hardness, improved toughness over conventional microcrystalline diamond, low friction, and good adhesion to titanium alloys. Nanostructured processing applied to hydroxyapatite coatings is used to achieve the desired mechanical characteristics and enhanced surface reactivity and has been found to increase osteoblast adhesion, proliferation, and mineralization. Finally, nanostructured metalloceramic coatings provide continuous variation from a nanocrystalline metallic bond at the interface to the hard ceramic bond on the surface and have the ability to overcome adhesion problems associated with ceramic hard coatings on metallic substrates. PMID:12908255

Catledge, Shane A; Fries, Marc D; Vohra, Yogesh K; Lacefield, William R; Lemons, Jack E; Woodard, Shanna; Venugopalan, Ramakrishna

2002-01-01

260

REVIEW ARTICLE: Medical implants based on microsystems  

NASA Astrophysics Data System (ADS)

The fast development of CMOS technologies to smaller dimensions led to very high integration densities with complex circuitry on very small chip areas. In 2006 Intel fabricated the first products in a 65 nm technology. The cointegration of microsensors or actuators together with the very low power consumption of the CMOS circuitry is very well suited for use in implanted systems. Applications like intracranial or intraocular pressure measurements have become possible. This review presents an overview over actual applications and developments of sensor/actuator-based microsystems for medical implants. It concentrates on the technical part of these investigations. It will mainly review work on systems measuring pressure in blood vessels and on systems for ophthalmic applications.

Mokwa, W.

2007-05-01

261

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

262

Tribological behavior of duplex coating improved by ion implantation  

Microsoft Academic Search

In the present paper the tribological behavior of the coatings are discussed. Duplex coatings were applied on cold working steel 100Cr6. Samples were plasma nitrided at different thickness of plasma surface layers. TiN was deposited with a classic BALZERS PVD equipment and subsequent ion implantation. Ion implantation was provided with N5+ ions. The other samples were produced with IBAD technology

D. Kaka; B Škoric; M Rakita

2004-01-01

263

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

264

The Adaptation of Three Subjects from the First Year of Psychology Studies of the University of Salamanca (Spain) for Teaching Within the Framework of the European Credit Transfer System (ECTS)  

Microsoft Academic Search

We report a pilot program set up at the School of Psychology of the University of Salamanca (Spain) as a step to precede adapting three subjects to the European Credit Transfer System (ECTS). After reviewing the relevant literature, we contacted via e-mail 30 schools of psychology in 13 countries with which we exchange students through the Erasmus-Socrates Program in order

José M. Arana; M. Angeles Mayor; Begoña Zubiauz; David L. Palenzuela

2005-01-01

265

Management of peri-implantitis  

PubMed Central

Peri-implantitis is a site-specific infectious disease that causes an inflammatory process in soft tissues, and bone loss around an osseointegrated implant in function. The etiology of the implant infection is conditioned by the status of the tissue surrounding the implant, implant design, degree of roughness, external morphology, and excessive mechanical load. The microorganisms most commonly associated with implant failure are spirochetes and mobile forms of Gram-negative anaerobes, unless the origin is the result of simple mechanical overload. Diagnosis is based on changes of color in the gingiva, bleeding and probing depth of peri-implant pockets, suppuration, X-ray, and gradual loss of bone height around the tooth. Treatment will differ depending upon whether it is a case of peri-implant mucositis or peri-implantitis. The management of implant infection should be focused on the control of infection, the detoxification of the implant surface, and regeneration of the alveolar bone. This review article deals with the various treatment options in the management of peri-implantitis. The article also gives a brief description of the etiopathogenesis, clinical features, and diagnosis of peri-implantitis.

Prathapachandran, Jayachandran; Suresh, Neethu

2012-01-01

266

Novel biomedical implant interconnects utilizing micromachined LCP  

NASA Astrophysics Data System (ADS)

Micro- and nano-MEMS technology is being increasingly exploited in biomedical applications, such as large electrode-count neural prosthesis probe arrays. However, a bottleneck in fully utilizing this technology has been the interconnect between the implanted MEMS device and the external system connected to the implanted device. Since the implanted MEMS device is capable of having a large number of elements, the interconnect must have a sufficient number of electrical connections to communicate with each and every element. Complicating this is the fact that the interconnect requirements may include electrical signals, microfluidics transport and optical signals, all packaged in a miniature biocompatible interconnect cable. Micromachined liquid crystal polymer (LCP) is a promising technology for this application, due to LCP's biocompatibility, chemical inertness, electromechanical properties and its ability to be micromachined. This paper presents the results from the development of surface micromachining techniques compatible with LCP, and is demonstrated in the realization of a prototype micromachined LCP biomedical interconnect device. In particular, the development of the interconnect device demonstrates the realization of biocompatible connectors with high-density ultra-fine pitch electrical traces.

Dean, Robert N., Jr.; Weller, Jenny; Bozack, Michael; Farrell, Brian; Jauniskis, Linas; Ting, Joseph; Edell, David; Hetke, Jamille

2004-10-01

267

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

268

Hardness of Ion Implanted Ceramics.  

National Technical Information Service (NTIS)

It has been established that the wear behavior of ceramic materials can be modified through ion implantation. Studies have been done to characterize the effect of implantation on the structure and composition of ceramic surfaces. To understand how these c...

W. C. Oliver C. J. McHargue G. C. Farlow C. W. White

1985-01-01

269

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

270

Asymmetric implants for breast asymmetry.  

PubMed

The indications, advantages, and disadvantages of round and anatomical implants have previously been described. The principles of biodimensional implant selection have been developed by several authors, where the objective choice of breast prosthesis for augmentation is based on the patient's breast tissues. This process has largely been applied to anatomical implant selection. We report a case of breast asymmetry, where we have applied the same concepts in the selection of implants based on tissue dimension. This resulted in an anatomical implant being used to augment the left breast, and a round implant on the right. To our knowledge a round implant and an anatomical implant have not previously been employed in the same patient to correct breast asymmetry. This resulted in excellent postoperative symmetry. PMID:22542729

Mallucci, P; Branford, O A

2012-11-01

271

Hydroxylapatite Otologic Implants  

SciTech Connect

A Cooperative Research and Development Agreement (CRADA) between Lockheed Martin Energy Research Corporation (LMER) and Smith and Nephew Richards Inc. of Bartlett, TN, was initiated in March 1997. The original completion date for the Agreement was March 25, 1998. The purpose of this work is to develop and commercialize net shape forming methods for directly creating dense hydroxylapatite (HA) ceramic otologic implants. The project includes three tasks: (1) modification of existing gelcasting formulations to accommodate HA slurries; (2) demonstration of gelcasting to fabricate green HA ceramic components of a size and shape appropriate to otologic implants: and (3) sintering and evaluation of the HA components.

McMillan, A.D.; Lauf, R.J.; Beale, B.; Johnson, R.

2000-01-01

272

The impact of network and recency effects on the adoption of e-collaboration technologies in online communities  

Microsoft Academic Search

This study investigates the impact that network and recency effects have on the adoption of e-collaboration technologies (ECT).\\u000a The network effect is a widely documented phenomenon affecting the adoption of technology in the real world. However, its\\u000a impact in virtual workspaces remains relatively underexplored. We know little about whether the observed network effect in\\u000a offline settings also applies to online

Gang Peng; Peter Woodlock

2009-01-01

273

The ruptured PIP breast implant.  

PubMed

Public concern erupted about the safety of Poly Implant Prothèse (PIP) breast implants when it was revealed in 2011 that they contained an inferior, unlicensed industrial-grade silicone associated with a high rate of rupture. There followed national guidance for UK clinicians, which led to a considerable increase in referrals of asymptomatic women for breast implant assessment. In this review we discuss possible approaches to screening the PIP cohort and the salient characteristics of a ruptured implant. PMID:23622796

Helyar, V; Burke, C; McWilliams, S

2013-08-01

274

Complications of cosmetic iris implants.  

PubMed

Cosmetic intraocular iris implants for the purpose of changing iris color have recently been developed; however, little is known about their safety. We report a patient who had bilateral implantation of colored silicone iris implants solely for cosmetic reasons. The rapid development of uveitis, corneal decompensation, and ocular hypertension resulted in the need for explantation of the implants. Placement of these devices should require specific medical indications and meticulous surgery with early and long-term evaluation. PMID:18571095

Thiagalingam, Sureka; Tarongoy, Pamela; Hamrah, Pedram; Lobo, Ann-Marie; Nagao, Karina; Barsam, Charles; Bellows, Robert; Pineda, Roberto

2008-07-01

275

Performance measures of implant antennas  

Microsoft Academic Search

Modern electronic medical implants have reached a high degree of complexity. This has increased the demands on the communication link with the implant, both regarding the bandwidth and the communication distance. A medical communication system at RF frequencies has been standardised, the Medical Implant Communication System (MICS), which use a frequency allocation of 402 ¿ 405 MHz. This frequency band

Anders J. Johansson

2006-01-01

276

Studies of rejected dental Ti-implants by laser microspectral analysis  

NASA Astrophysics Data System (ADS)

The surface of rejected dental implants was studied. It was clarified that the implant rejection happened in a case of incomplete osteointegration of implants, incomplete proliferation of a bone tissue in holes. In a turn, osteointegration depends on uniformity of deposition of a titanium-hydroxyapatite (Ti/HA) coating and the impurities composition of used materials. The excess of exterior elements imported at technological processes also influences on adhesion.

Surmenko, Elena L.; Tuchin, Valery V.; Sokolova, Tatiana N.; Seryanov, Yury V.

2003-10-01

277

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

278

A composite hip implant.  

PubMed

Composites are made of two or more different components that combine their properties into a new material. By modifying the type or structure or volume of the components, a theoretically endless number of new materials can be produced and their properties can be altered as desired. A composite hip implant made of carbon fiber and polysulfone is described. PMID:3405625

Mendes, D G; Roffman, M; Soudry, M; Angel, D; Boss, J; Charit, Y; Rotem, A; Hunt, M; Mordechovitch, D

1988-04-01

279

Potentially implantable miniature batteries.  

PubMed

All presently used batteries contain reactive, corrosive or toxic components and require strong cases, usually made of steel. As a battery is miniaturized, the required case dominates its size. Hence, the smallest manufactured batteries are about 50 mm3 in size, much larger then the integrated circuits or sensors of functional analytical packages, as exemplified by implantable glucose sensors for diabetes management. The status of the miniaturization of the power sources of such implantable packages is reviewed. Three microcells, consisting only of potentially harmless subcutaneously implantable anodes and cathodes, are considered. Because their electrolyte would be the subcutaneous interstitial fluid, the cells do not have a case. One potentially implantable cell has a miniature Nafion-coated Zn anode and a biocompatible hydrogel-shielded Ag/AgCl cathode. The core innovation on which the cell is based is the growth of a hopeite-phase Zn2+ conducting solid electrolyte film on the discharging anode. The film blocks the transport of O2 to the Zn, preventing its corrosion, while allowing the necessary transport of Zn2+. The second cell, with the same anode, would have a bioinert hydrogel-shielded wired bilirubin oxidase-coated carbon cathode, on which O2 dissolved in the subcutaneous fluid would be electroreduced to water. In the third cell, the glucose of the subcutaneous interstitial would be electrooxidized to gluconolactone at an implanted wired glucose anode, similar to that tested now for continuous glucose monitoring in diabetic people, and O2 in the subcutaneous fluid would be electroreduced to water on its wired bilirubin oxidase cathode. PMID:16538459

Heller, Adam

2006-06-01

280

[Implants: where, when, how, why?].  

PubMed

The concept of osseointegration which means direct contact between bone and implant has provided new possibilities for implantology and a much more serious approach of the method. Implants are placed following a two phases schedule: first a surgical procedure with a sophisticated insertion of the implants and 3 to 6 months later a prosthetic procedure. Implants can be used in many applications: single tooth replacement, partial and total edentulism. Osseous grafts can be added if needed. Connected and non-connected bridges are built on implants with a tendency to use more non-connected bridges. If all the conditions of placement of the implants and of realisation of the prosthetic supra-structures are respected, there are very few complications. Implants are actually the unique possibility to give the patient fixed oral rehabilitation while preserving the remaining bone and teeth. PMID:2077575

Daelemans, P; Malevez, C

1990-01-01

281

Continuous infusion with implantable pumps: expanding the radiologist's role.  

PubMed

Drug infusion systems attract increasing attention as biomedical technology offers miniaturized devices for targeted delivery of therapeutic substances on an outpatient basis. We have used a totally implantable, subcutaneous pump, externally programmable by radiofrequency link, learning the technique of implantation and management and using various imaging modalities for the diagnosis and control of complications. The procedure for implanting systems for continuous intrathecal analgesia and systemic intravenous chemotherapy is described. Our experience of the latter is made up of 296 implants in 290 patients. The selected infusion pump proved reliable and acceptable to patients and the quality of life, given the reduced drug toxicity, more than good. The complications were few both in frequency and in severity. The setting-up of a long-term infusion system, when major surgery is not needed, can fall within the interventional radiologist's field, partly because of a good cost-benefit ratio. PMID:1906807

Damascelli, B; Bonalumi, M G; Marchianò, A; Spreafico, C; Garbagnati, F; Amadeo, A; Salvetti, M; Frigerio, L F; Piragine, G; Cesa Bianchi, A

1991-01-01

282

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

283

Dynamic implant valve approach for dental implant procedures.  

PubMed

Objective: To present the results of our current research involving the dynamic implant valve approach (DIVA) in cases with human patients. Methods: The new kind of implant was designed with an internal sealing screw that might serve for drug delivery system and possible endoscopic direct observation via its channel. The DIVA was used in cases when the implant insertion should be combined with the maxillary sinus floor lifting and/or bone augmentation procedure. A total of 63 patients (female n = 31, male n = 32, age range 33-67 years old, mean age 49 years old) were treated with DIVA and 218 new type implants were inserted. Results: Out of 218 inserted implants, 146 implants were inserted in the maxilla with bone level < 5 mm, and 72 implants were inserted in the maxilla with bone level > 5 mm. The number of implants per patients varied from one to eight. The failure consisted of seven implants (3.2%) in five patients. No correlation was found between failure cases and the bone density or quality. Follow up (4 to 18 months) showed that in 211 cases (96.8%), the implantation was totally successful both from objective clinical, imaging (cone beam computed tomography) and subjective patients' viewpoints. Conclusion: The new dynamic implant valve approach simplified dental implantation procedure and postoperative treatment. The implant with an inner sealing screw could be considered for use in cases when elevation of the maxillary sinus membrane is needed, as well as in cases when bone augmentation procedures or future treatment might be suspected. PMID:25028685

Nahlieli, Oded

2014-01-01

284

A retrospective study of paediatric health and development following pre-implantation genetic diagnosis and screening  

Microsoft Academic Search

Pre-implantation genetic diagnosis and screening (PGD and PGS) are treatments for patients that have (or are carriers of) an inherited genetic disorder, or who have had a history of miscarriage, problems with embryo implantation, etc. Often conducted alongside assisted reproductive technologies (ART), a number of embryos are produced, and the DNA and chromosomes of each are tested for various disorders

Mark Olive; Alison Lashwood; Tony Solomonides

2011-01-01

285

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

286

Biphasic electrical current stimulator for early bone formation in dental implant  

Microsoft Academic Search

Since the discovery of piezoelectric properties of natural bone, electrical stimulation has been widely used in the clinical treatment of orthopedic fracture. Nevertheless, in dental implant technologies, it is the methods of surface modification that has been recently developed to enhance early osteointegration between implant's surface and surrounding tissue. In this paper, in order to accelerate bone formation, we developed

Jong Keun Song; Sung June Kim

287

Nitinol Surfaces for Implantation  

Microsoft Academic Search

Nitinol, a group of nearly equiatomic Ni-Ti alloys, steadily conquers new areas of application. Because of the need to keep\\u000a a low profile of miniature implant devices, and considering the lack of compatibility between Nitinol superelasticity and\\u000a the mechanical properties of traditional coatings, bare surfaces are of interest. In this article, an overview of our studies\\u000a of bare Nitinol surfaces

Svetlana Shabalovskaya; Gianni Rondelli; Markus Rettenmayr

2009-01-01

288

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

289

[Osseointegration and dental implants].  

PubMed

The concept of osseointegration was developed and the term was coined Dr. Brånemark. Osseointegration is initially defined as the direct structural and functional connection between living bone and surface living bone and the surface of a loadbearing artificial implant, typically made of titanium. Osseointegration required new bone formation around fixture, the healing of implant system is similar to primary bone healing. Bone formation on the titanium surface needs the formation of oxide film, deposition of calcium phosphate, and deposition of the protein. However, osseointegration is not the direct bonding between bone and the titanium surface, there exists an amorphous layer including osteopontin or osteocalcin that osteoblasts use them as a scaffold. In clinical the ratio of bone and implant contacts is called as BIC, and BIC was from 40% to 60% if the osseointegration was obtained. Numerous studies were performed for the surface modification to increase the score of BIC. Recently, surface treatments such as glow discharge, acid-etch, or UV irradiation have been found to be effective for osseointegration. Further modification would be needed to maintain the osseointegration as well as to obtain the osseointegration. PMID:24473360

Goto, Tetsuya

2014-02-01

290

An investigation into the use of a mixture model for simulating the electrical properties of soil with varying effective saturation levels for sub-soil imaging using ECT  

NASA Astrophysics Data System (ADS)

A new visualisation tool is being developed for seed breeders, providing on-line data for each individual plant in a screening programme. It will be used to indicate how efficiently each plant utilises the water and nutrients available in the surrounding soil. This will facilitate early detection of desirable genetic traits with the aim of increased efficiency in identification and delivery of tomorrow's drought tolerant food crops. Visualisation takes the form of Electrical Capacitance Tomography (ECT), a non-destructive and non-intrusive imaging technique. Measurements are to be obtained for an individual plant thus allowing water and nutrient absorption levels for an individual specimen to be inferred. This paper presents the inverse problem, discusses the inherent challenges and presents the early experimental results. Two mixture models are evaluated for the prediction of electrical capacitance measurement data for varying effective soil saturation levels using a finite element model implemented in COMSOL Multiphysics. These early studies have given the research team an understanding of the technical challenges that must now be addressed to take the current research into the world of agri-science and food supply.

Hayes, R. R.; Newill, P. A.; Podd, F. J. W.; York, T. A.; Grieve, B. D.; Dorn, O.

2010-11-01

291

Etonogestrel implant (Implanon) for contraception.  

PubMed

Levonorgestrel 38 mg subdermal implant (Norplant), intended to provide contraception for 5 years, was withdrawn in the UK in 1999 due to unwanted effects (menstrual disturbances) and difficulties in removing the device. Since then, [symbol: see text]etonogestrel implant (Implanon-Organon), another progestogen--only subdermal contraceptive device, has become available in the UK. The manufacturer claims that etonogestrel implant provides contraception for up to 3 years and is easy to insert and remove. Here, we consider the place of etonogestrel implant. PMID:11526801

2001-08-01

292

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

293

Short implants: A systematic review  

PubMed Central

Background: Short implants are manufactured for use in atrophic regions of the jaws. Although many studies report on short implants as ?10 mm length with considerable success, the literature regarding survival rate of ?7 mm is sparse. Purpose: The purpose of this study was to systematically evaluate the publications concerning short dental implants defined as an implant with a length of ?7 mm placed in the maxilla or in the mandible. Materials and Methods: A Medline and manual search was conducted to identify studies concerning short dental implants of length ?7 mm published between 1991 and 2011. The articles included in this study report data on implant length ?7 mm, such as demographic variables, implant type, location in jaws, observation time, prostheses and complications. Results: The 28 included studies represent one randomized controlled trial, 12 prospective studies and 10 retrospective studies. The survival rate of short implant was found to be increased from 80% to 90% gradually, with recent articles showing 100%. Conclusion: When severe atrophy of jaws was encountered, short and wide implants can be placed successfully.

Karthikeyan, I.; Desai, Shrikar R.; Singh, Rika

2012-01-01

294

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.

2013-01-01

295

Developing a wireless implantable body sensor network in MICS band.  

PubMed

Through an integration of wireless communication and sensing technologies, the concept of a body sensor network (BSN) was initially proposed in the early decade with the aim to provide an essential technology for wearable, ambulatory, and pervasive health monitoring for elderly people and chronic patients. It has become a hot research area due to big opportunities as well as great challenges it presents. Though the idea of an implantable BSN was proposed in parallel with the on-body sensor network, the development in this area is relatively slow due to the complexity of human body, safety concerns, and some technological bottlenecks such as the design of ultralow-power implantable RF transceiver. This paper describes a new wireless implantable BSN that operates in medical implant communication service (MICS) frequency band. This system innovatively incorporates both sensing and actuation nodes to form a closed-control loop for physiological monitoring and drug delivery for critically ill patients. The sensing node, which is designed using system-on-chip technologies, takes advantage of the newly available ultralow-power Zarlink MICS transceiver for wireless data transmission. Finally, the specific absorption rate distribution of the proposed system was simulated to determine the in vivo electromagnetic field absorption and the power safety limits. PMID:21571615

Fang, Qiang; Lee, Shuenn-Yuh; Permana, Hans; Ghorbani, Kamran; Cosic, Irena

2011-07-01

296

The implications of megatrends in information and communication technology and transportation for changes in global physical activity.  

PubMed

Physical inactivity accounts for more than 3 million deaths per year, most from non-communicable diseases in low-income and middle-income countries. We used reviews of physical activity interventions and a simulation model to examine how megatrends in information and communication technology and transportation directly and indirectly affect levels of physical activity across countries of low, middle, and high income. The model suggested that the direct and potentiating eff ects of information and communication technology, especially mobile phones, are nearly equal in magnitude to the mean eff ects of planned physical activity interventions. The greatest potential to increase population physical activity might thus be in creation of synergistic policies in sectors outside health including communication and transportation. However, there remains a glaring mismatch between where studies on physical activity interventions are undertaken and where the potential lies in low-income and middle-income countries for population-level effects that will truly affect global health. PMID:22818940

Pratt, Michael; Sarmiento, Olga L; Montes, Felipe; Ogilvie, David; Marcus, Bess H; Perez, Lilian G; Brownson, Ross C

2012-07-21

297

Microstructural characterization of iron implanted sapphire nanocomposites  

SciTech Connect

Nanocomposites of iron in sapphire ({alpha}-Al{sub 2}O{sub 3}) prepared by ion implantation have been studied as a model to investigate the potential of such materials for applications in high technology areas. The implantation was performed with 160 keV ions at several doses; the nanocomposites were then annealed at selected temperatures between 700 and 1,400 C in an Ar-4%H{sub 2} atmosphere for 1 hour. Rutherford backscattering spectroscopy and high resolution transmission electron microscopy (TEM) were used to characterize the structure of these nanocomposites. Measurements showed that damage depth extended to about 300 nm and the embedded iron extended to about 200 nm. This region became amorphous when the fluence reaches 2 {times} 10{sup 17} Fe/cm{sup 2} at this energy. Thermal annealing could be used to restore the crystallinity to the damaged near-surface region, to form the metallic colloids, and also to coarsen the precipitates. In the case of high dose implantation, oriented precipitates with diameters of 2 to 3 nm were identified by TEM techniques as {alpha}-Fe which had the following orientation relationship with the sapphire matrix: <111>{sub Fe} {parallel} <310>{sub Sapphire} and {l_brace}01{bar 1}{r_brace}{sub Fe} {parallel} {l_brace}006{r_brace}{sub Sapphire}. The optical density and luminescence spectra were also measured. The predominant defects were oxygen vacancies with two electrons (F center) at the known absorption peak of 200 nm.

Ren, S.X.; McHargue, C.J. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering; Allard, L.F.; Chen, Y.; Hunn, J.D.; Lucas, B.N.; Williams, R.K. [Oak Ridge National Lab., TN (United States)

1994-12-31

298

Patient specific implants: scope for the future.  

PubMed

"Patient Specific" technology introduced in last 5 years, slowly gained popularity but has currently plateaued. We have a number of studies on patient specific instruments where they have been compared with conventional jigs in total knee arthroplasty and reported to have no clear additional benefits. This review discusses their intraoperative and postoperative advantages/disadvantages and cost effectiveness and provides a synopsis in light of current literature. Patient specific implants are not freely available yet, and there is no scientific literature reporting on their use in clinical practice. PMID:24691710

Maniar, Rajesh N; Singhi, Tushar

2014-06-01

299

Medical implants and fibrosis-inducing agents  

US Patent & Trademark Office Database

Implants are used in combination with a fibrosis-inducing agent in order to induce fibrosis that may otherwise not occur when the implant is placed within an animal or increase fibrosis between the implant and the host tissue.

2007-01-23

300

Ion Implantation in Perovskite Type Ferroelectrics.  

National Technical Information Service (NTIS)

The object of this work was to study ion implantation in perovskite ferroelectrics and to investigate the conductive behavior of implanted layers. Implantation experiments were carried out on strontium titanate, barium titanate (single crystal and ceramic...

R. Gerson

1979-01-01

301

Cohesive gel naturally-shaped breast implants  

Microsoft Academic Search

According to the author, cohesive gel naturally-shaped breast implants provide particular benefits for patients who prefer retromammary implant placement. He discusses his experimence with these implants in 50 patients.

Richard Sadove

2003-01-01

302

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.

Leung, Ka-Ngo (Hercules, CA)

1996-01-01

303

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

304

Implantable medical sensor system  

DOEpatents

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 circuit changes its characteristics, an external interrogator transmits a signal transdermally to the transducer, and the concentration of the analyte is determined from the measured changes in the circuit. This invention may be used for minimally invasive monitoring of blood glucose levels in diabetic patients.

Darrow, Christopher B. (Pleasanton, CA) [Pleasanton, CA; Satcher, Jr., Joe H. (Modesto, CA); Lane, Stephen M. (Oakland, CA) [Oakland, CA; Lee, Abraham P. (Walnut Creek, CA) [Walnut Creek, CA; Wang, Amy W. (Berkeley, CA) [Berkeley, CA

2001-01-01

305

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

306

DIY 3D Printing of Custom Orthopaedic Implants: A Proof of Concept Study.  

PubMed

3D printing is an emerging technology that is primarily used for aiding the design and prototyping of implants. As this technology has evolved it has now become possible to produce functional and definitive implants manufactured using a 3D printing process. This process, however, previously required a large financial investment in complex machinery and professionals skilled in 3D product design. Our pilot study's aim was to design and create a 3D printed custom orthopaedic implant using only freely available consumer hardware and software. PMID:24574013

Frame, Mark; Leach, William

2014-03-01

307

Implant-retained mandibular overdentures with ITI implants.  

PubMed

This prospective study has been designed to compare the results of immediate and delayed loading of implant-retained mandibular overdentures after a 2-year follow-up. Twenty patients have been randomly divided into two groups. Group 1 patients (test group) received four ITI implants in the intraforaminal area of the mandible. Octa abutments were immediately screwed on implants; 2 days after surgery, the implants were rigidly connected with a U-shaped Dolder gold bar and loaded with an overdenture. Group 2 patients (control group) received, in the same area, the same type and number of implants, which were left to heal according to the standard protocol. At 3-4 months, Octa abutments were screwed on the implants and the same prosthetic procedure of the test group was applied. The minimum follow-up period lasted 2 years, with recall appointments at 2 weeks, 1, 3, 6 months, 1 year and every following year postoperatively, evaluating: MPI, MBI, PD, Periotest and radiographic peri-implant bone resorption. Success criteria according to Albrektsson et al. were used. Only one implant out of the 40 of group 2 failed, whereas none failed in group 1. No statistical difference of the clinical parameters evaluated was noticed in the two groups. Therefore, immediate loading of implants, if connected with a U-shaped bar, can provide the same results of the 'traditional' technique as far as osseointegration and short-term survival rates of implants are concerned. Moreover, this method significantly shortens the treatment period, thus increasing patient satisfaction. PMID:12453126

Romeo, Eugenio; Chiapasco, Matteo; Lazza, Andrea; Casentini, Paolo; Ghisolfi, Marco; Iorio, Marco; Vogel, Giorgio

2002-10-01

308

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

309

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).

310

Body Implanted Medical Device Communications  

Microsoft Academic Search

The medical care day by day and more and more is associated with and reliant upon concepts and advances of electronics and electromagnetics. Numerous medical devices are implanted in the body for medical use. Tissue implanted devices are of great interest for wireless medical applications due to the promising of different clinical usage to promote a patient independence. It can

Kamya Yekeh Yazdandoost; Ryuji Kohno

2009-01-01

311

Implanted antenna for biomedical applications  

Microsoft Academic Search

In this paper we present the design, realization and measurements of a first prototype of a complete implantable device. The RF system, working over the medical implanted communication systems (MICS) bandwidth and composed of the antenna, the battery, the transceiver for the data communication and the insulation material, has been designed and realized in order to be integrated with an

F. Merli; L. Bolomey; E. Meurville; A. K. Skrivervik

2008-01-01

312

Recoverable Temperature-Sensing Implant.  

National Technical Information Service (NTIS)

A temperature-sensing device suitable for chronic implantation in 3- to 8-kg. animals was designed to be recoverable. The implant case and screw-on cap were machined from Teflon stock, which provides a moisture-impervious seal between case and cap. The co...

H. Buchanan W. F. Moore C. R. Richter

1969-01-01

313

Dental implant changes following incineration.  

PubMed

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 available. Currently, there are no experimental investigations to determine what changes occur to dental implants following high temperature exposure. A selection of dental implants was radiographed, utilizing purpose built apparatus to allow standard methodology. They were then heated in an INFI-TROL™ kiln to a maximum temperature of 1125°C and the radiographic procedure repeated. Image subtraction evaluation of the radiographs was recorded using Adobe(®) Photoshop(®). Both commercially pure titanium and titanium alloy dental implants survived the incineration and there was oxidation of the surface leading to minor alteration of the image. There was, however, no detectable sagging of the implants. The results of this research suggest that dental implants are still recognizable following incineration. In scenarios commonly seen by forensic odontologists, heat will destroy both teeth and conventional dental restorative materials. Implants, however, will resist these conditions and will also retain the features necessary to identify the type of implant. PMID:20880643

Berketa, J; James, H; Marino, V

2011-04-15

314

Sequential provisional implant prosthodontics therapy.  

PubMed

The fabrication and long-term use of first- and second-stage provisional implant prostheses is critical to create a favorable prognosis for function and esthetics of a fixed-implant supported prosthesis. The fixed metal and acrylic resin cemented first-stage prosthesis, as reviewed in Part I, is needed for prevention of adjacent and opposing tooth movement, pressure on the implant site as well as protection to avoid micromovement of the freshly placed implant body. The second-stage prosthesis, reviewed in Part II, should be used following implant uncovering and abutment installation. The patient wears this provisional prosthesis until maturation of the bone and healing of soft tissues. The second-stage provisional prosthesis is also a fail-safe mechanism for possible early implant failures and also can be used with late failures and/or for the necessity to repair the definitive prosthesis. In addition, the screw-retained provisional prosthesis is used if and when an implant requires removal or other implants are to be placed as in a sequential approach. The creation and use of both first- and second-stage provisional prostheses involve a restorative dentist, dental technician, surgeon, and patient to work as a team. If the dentist alone cannot do diagnosis and treatment planning, surgery, and laboratory techniques, he or she needs help by employing the expertise of a surgeon and a laboratory technician. This team approach is essential for optimum results. PMID:23220306

Zinner, Ira D; Markovits, Stanley; Jansen, Curtis E; Reid, Patrick E; Schnader, Yale E; Shapiro, Herbert J

2012-01-01

315

Ion Implantation of Ceramic Bearings.  

National Technical Information Service (NTIS)

This report explores the use of ion implantation techniques to form solid lubricating surfaces on all ceramic (silicon nitride) and hybrid ball bearings. Techniques were developed to implant and/or cost silicon nitride and 52100 bearing steel with MoS2, B...

A. J. Armini S. N. Bunker

1989-01-01

316

[Conservative femoral implants. Short stems].  

PubMed

Uncemented hip replacement matches the best results of classic cemented replacements. With the aim of preserving bone and soft tissue, implants with shorter stems and proximal metaphyseal support have been developed. Likewise, the lack of distal load should avoid cortical diaphyseal remodelling phenomena and the thigh pain of some cylindrical and wedge implants. The resurfacing implant, very popular as a conservative hip replacement in the young adult, has disadvantages associated with the fragility of the neck and with large head metal friction torque. Short stem hip replacement may be a reasonable alternative to classic implants and surface hip replacements. The different designs of conservative short stem implants are analysed, and are classified according to their morphology and biomechanical characteristics. Some medium term series show promising results. PMID:23177948

Valverde-Mordt, C; Valverde-Belda, D

2012-01-01

317

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

318

Gain coupled AlGaInAs\\/GaInAs DFB-lasers utilizing gratings by masked implantation enhanced intermixing  

Microsoft Academic Search

Masked implantation enhanced intermixing (MIEI) offers the advantage of a full planar technology for realization of gain coupled (GC)-DFB-lasers with the potential of a simplified laser\\/waveguide coupling with a reduced number of process steps for integration. The high implantation contrast reached in the AlGaInAs\\/GaInAs material system offers the capability of defining DFB-gratings by implantation. The process is based on the

A. Hase; C. Kaden; H. Kovac; V. Hofsass; H. Schmidt; H. Kunzel; H. Schweizer

1994-01-01

319

Transcatheter aortic valve implantation.  

PubMed

Transcatheter aortic valve implantation (TAVI) was introduced experimentally in 1989, based on a newly developed heart valve prosthesis - the stentvalve. The valve was invented by a Danish cardiologist named Henning Rud Andersen. The new valve was revolutionary. It was foldable and could be inserted via a catheter through an artery in the groin, without the need for heart lung machine. This allowed for a new valve implantation technique, much less invasive than conventional surgical aortic valve replacement (SAVR). Surgical aortic valve replacement is safe and improves symptoms along with survival. However, up to 1/3 of patients with aortic valve stenosis cannot complete the procedure due to frailty. The catheter technique was hoped to provide a new treatment option for these patients. The first human case was in 2002, but more widespread clinical use did not begin until 2006-2010. Today, in 2011, more than 40,000 valves have been implanted worldwide. Initially, because of the experimental character of the procedure, TAVI was reserved for patients who could not undergo SAVR due to high risk. The results in this group of patients were promising. The procedural safety was acceptable, and the patients experienced significant improvements in their symptoms. Three of the papers in this PhD-thesis are based on the outcome of TAVI at Skejby Hospital, in this high-risk population [I, II and IV]. Along with other international publications, they support TAVI as being superior to standard medical treatment, despite a high risk of prosthetic regurgitation. These results only apply to high-risk patients, who cannot undergo SAVR. The main purpose of this PhD study has been to investigate the quality of TAVI compared to SAVR, in order to define the indications for this new procedure. The article attached [V] describes a prospective clinical randomised controlled trial, between TAVI to SAVR in surgically amenable patients over 75 years of age with isolated aortic valve stenosis. The study was terminated prematurely, as patients undergoing TAVI showed a statistically non-significant trend towards more complications than SAVR patients. Although non-significant the study was closed for ethical reasons. At present, scientific evidence supports TAVI as being superior to standard medical treatment, in patients who cannot undergo SAVR due to high- predicted risk. However, in patients who are surgically amenable, current publications suggest that TAVI using presently available devices is not competitive to SAVR, with regards to procedural safety and outcome. PMID:23290293

Nielsen, Hans Henrik Møller

2012-12-01

320

Investigation of the silicone structure in breast implants using (1)H NMR.  

PubMed

Against the background of the scandal about low-grade silicone breast implants of the French manufacturer Poly Implant Prothese (PIP), several types of implants were examined using (1)H NMR spectroscopy. The intention was to classify an implant according to its silicone structure. Therefore, the certificated raw material of the American silicone producer Nusil Technology was analyzed and used as a reference. The list of tested implants consists of implants by PFM medical, PIP, Silimed, Rofil, Eurosilicone, Mentor, Perouse Plastie, Polytech, Nagor, CUI, and McGhan. In the (1)H NMR spectrum the signal of the vinyl group, which is used to cross link silicone rubbers, is visible. It is possible to differentiate between silicones which have a vinyl terminated end group and silicones whose vinyl group is located within the chain of the polymer. The two different types of the vinyl group are one mean to classify the implants. Other categories besides the type of vinyl include the relative amount of the remaining vinyl in the implant and the chemical structure of the material used for the production of the envelope. With these characteristics the examined implants could be grouped into four types. PMID:24342752

Formes, Andreas; Diehl, Bernd

2014-05-01

321

Ion implantation for high performance III-V JFETS and HFETS  

SciTech Connect

Ion implantation has been an enabling technology for realizing many high performance electronic devices in III-V semiconductor materials. We report on advances in ion implantation processing for GaAs JFETs (joint field effect transistors), AlGaAs/GaAs HFETs (heterostructure field effect transistors), and InGaP or InAlP-barrier HFETs. The GaAs JFET has required the development of shallow p-type implants using Zn or Cd with junction depths down to 35 nm after the activation anneal. Implant activation and ionization issues for AlGaAs are reported along with those for InGaP and InAlP. A comprehensive treatment of Si-implant doping of AlGaAs is given based on donor ionization energies and conduction band density-of-states dependence on Al-composition. Si and Si+P implants in InGaP are shown to achieve higher electron concentrations than for similar implants in AlGaAs due to absence of the deep donor level. An optimized P co- implantation scheme in InGaP is shown to increase the implanted donor saturation level by 65%.

Zolper, J.C.; Baca, A.G.; Sherwin, M.E.; Klem, J.F.

1996-06-01

322

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

323

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.

Lee, Hyoung-Doo

2012-01-01

324

Implantable functional gastrointestinal neurostimulation.  

PubMed

Neural Gastrointestinal Electrical Stimulation (NGES) is a new microprocessor-based method for invoking gastric or colonic contractions by generating multi-channel, high energy, high frequency waveforms. It has been shown that when applied to the lower stomach, NGES offers the possibility for enhancing propulsive peristalsis for the treatment of gastric motor dysfunctions, or for producing retrograde peristalsis for the treatment of obesity. When applied to the colon, NGES can be utilized either for propulsive control in severe constipation or for invoked retrograde contractility. This paper briefly discusses the implementation of an implantable neurostimulator and summarizes the performance of the NGES technique in acute tests on experimental animals and humans, and in chronic tests on animals. These experimental tests indicate that NGES is successful in accelerating gastric emptying of both liquids and solids, and in producing strong, externally-controlled, retrograde contractions. PMID:19963851

Jurkov, A S; Arriagada, A; Mintchev, M P

2009-01-01

325

Implantate in der Augenheilkunde  

NASA Astrophysics Data System (ADS)

Im Bereich der Augenheilkunde findet sich die weltweit am häufigsten ausgeführte chirurgische Massnahme, die operative Behandlung des Grauen Stars: die Katarakt. Bei der Katarakt handelt es sich um eine Eintrübung der natürlichen Augenlinse, die sich je nach Stadium der Erkrankung leicht opak, über milchig bis zu bräunlich präsentiert. Mit dieser Zunahme der Undurchlässigkeit für das sichtbare Licht geht eine Abnahme des Sehvermögens einher, die bis zur totalen Erblindung führen kann. Bedingt durch die sehr eingeschränkten chirurgischen Möglichkeiten in den Ländern der Dritten Welt ist die Katarakt die Erblindungsursache Nummer 1 in der Welt. Ganz im Gegensatz hierzu ist in den industrialisierten Ländern Europas, Amerikas und Asiens die Katarakt-OP die sicherste chirurgische Intervention. In der Augenheilkunde werden Implantate aller drei Aggregatszustände verwendet.

Dresp, Joachim H.

326

Implants in maxillary sinus.  

PubMed

Augmentation of the floor of the maxillary sinus is an extremely important technique for posterior site development in the maxilla prior to implant placement. A number of techniques have been suggested and used in the past to deal with membrane perforations such as suturing the membrane, application of fibrin sealants oxidized regenerated cellulose and collagen membranes. The most important aspect of sinus grafting is the integrity of the sinus membrane solely to confine the graft. If membrane tears are not taken care of, graft material can extravasate into the antrum and block the ostium. The fast-resorbing membranes are not good enough to form bone as their integrity is lost before woven bone forms. The novel technique demonstrates the use of a slow-resorbing membrane not only for perforations, but even in circumstances where the sinus is devoid of a membrane, thus bypassing the waiting period for schnederian membrane regeneration prior to grafting. PMID:23833502

Gandhi, Yazad R; Singh, Mayank; Singh, Nimisha; Hariram

2012-07-01

327

Implants in maxillary sinus  

PubMed Central

Augmentation of the floor of the maxillary sinus is an extremely important technique for posterior site development in the maxilla prior to implant placement. A number of techniques have been suggested and used in the past to deal with membrane perforations such as suturing the membrane, application of fibrin sealants oxidized regenerated cellulose and collagen membranes. The most important aspect of sinus grafting is the integrity of the sinus membrane solely to confine the graft. If membrane tears are not taken care of, graft material can extravasate into the antrum and block the ostium. The fast-resorbing membranes are not good enough to form bone as their integrity is lost before woven bone forms. The novel technique demonstrates the use of a slow-resorbing membrane not only for perforations, but even in circumstances where the sinus is devoid of a membrane, thus bypassing the waiting period for schnederian membrane regeneration prior to grafting.

Gandhi, Yazad R.; Singh, Mayank; Singh, Nimisha; Hariram

2012-01-01

328

Evaluation of synthetic osteochondral implants.  

PubMed

This translational animal model study was designed to assess function, bone ingrowth and integration, and joint pathology associated with two different synthetic, bilayered osteochondral implants over a 3-month period after implantation into the femoral condyles of dogs. SynACart-Titanium (n?=?6) and SynACart-PEEK (n?=?6) (Arthrex, Naples, FL, and Sites Medical, Columbia City, IN) implants were press-fit into the lateral or medial femoral condyle (alternating location) of purpose-bred adult research dogs. Dogs were humanely euthanized 3 months after surgery and the operated knees were assessed radiographically, arthroscopically, grossly, and histologically. Based on all assessments, both types of implants were well tolerated and safe with no evidence for infection, migration, or rejection. Half of the SynACart-PEEK implants showed radiographic and histologic evidence of poor incorporation with all of these being in the lateral femoral condyle. SynACart-Titanium implants were considered effective in terms of integration into bone, lack of damage to surrounding and apposing articular cartilage, and maintenance of implant integrity and architecture for the duration of the study. PMID:24281985

Cook, James L; Kuroki, Keiichi; Bozynski, Chantelle C; Stoker, Aaron M; Pfeiffer, Ferris M; Cook, Cristi R

2014-08-01

329

Ultraviolet photofunctionalization of titanium implants.  

PubMed

In the face of growing demands and challenges in implant therapy, implant surfaces with improved biologic capabilities are required. This review paper summarizes the findings of recent in vitro and in vivo studies related to ultraviolet (UV) photofunctionalization of titanium. UV photofunctionalization is defined as an overall phenomenon of modification of titanium surfaces occuring after UV treatment, including the alteration of physicochemical properties and the enhancement of biologic capabilities. Bone morphogenesis around UV-treated titanium implants is distinctly improved compared with that seen around untreated control implants, leading to rapid and complete establishment of osseointegration with nearly 100% bone-to-implant contact in an animal model, as opposed to less than 55% for untreated implants. A series of in vitro studies demonstrated considerable enhancement of attachment, retention, and subsequent functional cascades of osteogenic cells derived from animals and humans after UV treatment. UV treatment converts titanium surfaces from hydrophobic to superhydrophilic and removes unavoidably contaminated hydrocarbons. UV-treated titanium surfaces also manifest a unique electrostatic status and act as direct cell attractants without the aid of ionic and organic bridges, which imparts a novel physicochemical functionality to titanium, which has long been understood as a bioinert material. UV treatment is simple and low in cost, and it has been proven effective for all types of titanium surfaces tested. These data suggest that UV photofunctionalization can be a novel, effective measure to improve implant therapy in the dental and orthopedic fields. Future research will focus on validating these findings in clinical studies. PMID:24451893

Ogawa, Takahiro

2014-01-01

330

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

331

Deep Trench Doping by Plasma Immersion Ion Implantation in Silicon  

SciTech Connect

The realization of three dimensional (3D) device structures remains a great challenge in microelectronics. One of the main technological breakthroughs for such devices is the ability to control dopant implantation along silicon trench sidewalls. Plasma Immersion Ion Implantation (PIII) has shown its wide efficiency for specific doping processing in semiconductor applications. In this work, we propose to study the capability of PIII method for large scale silicon trench doping. Ultra deep trenches with high aspect ratio were etched on 6'' N type Si wafers. Wafers were then implanted with a PIII Pulsion system using BF3 gas source at various pressures and energies. The obtained results evidence that PIII can be used and are of grateful help to define optimized processing conditions to uniformly dope silicon trench sidewalls through the wafers.

Nizou, S. [Universite Francois Rabelais, Tours, L.M.P, 16, rue Pierre et Marie Curie, B.P. 7155, F37071 TOURS Cedex (France); STMicroelectronics, 16, rue Pierre et Marie Curie, B.P. 7155, F37071 TOURS Cedex (France); Vervisch, V.; Etienne, H.; Torregrosa, F.; Roux, L. [Ion Beam Services, Rue Gaston Imbert Prolongee, ZI Peynier-Rousset, 13790, PEYNIER (France); Ziti, M.; Alquier, D. [Universite Francois Rabelais, Tours, L.M.P, 16, rue Pierre et Marie Curie, B.P. 7155, F37071 TOURS Cedex (France); Roy, M. [STMicroelectronics, 16, rue Pierre et Marie Curie, B.P. 7155, F37071 TOURS Cedex (France)

2006-11-13

332

[Actuator design and control exemplified by a urologic implant].  

PubMed

The state of the art concerning the use of actuators and sensors and the intelligent microprocessor-based control will be discussed on the basis of a novel urological implant, a fine tuned, sensor controlled artificial sphincter. A set of powerful actuators with a reaction time lower than 10 ms have been realised due to an appropriate design of components. This has been achieved at a supply voltage of 4.2 V and a power input lower than 0.1 mW. An optimal reliability as well as the comfort in operating the implant by the physician and the patient was gained by the use of different data technologies being adapted to the implanted system. PMID:12465309

Schostek, S; Ho, C N; Wassermann, H

2002-01-01

333

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.

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

2010-01-01

334

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

335

Hardness of ion implanted ceramics  

SciTech Connect

It has been established that the wear behavior of ceramic materials can be modified through ion implantation. Studies have been done to characterize the effect of implantation on the structure and composition of ceramic surfaces. To understand how these changes affect the wear properties of the ceramic, other mechanical properties must be measured. To accomplish this, a commercially available ultra low load hardness tester has been used to characterize Al/sub 2/O/sub 3/ with different implanted species and doses. The hardness of the base material is compared with the highly damaged crystalline state as well as the amorphous material.

Oliver, W.C.; McHargue, C.J.; Farlow, G.C.; White, C.W.

1985-01-01

336

A two-stage surgical approach to the treatment of severe peri-implant defect: a 30-month clinical follow-up report.  

PubMed

With the advance of dental implant technology and the consequential increase in its success rate, the implant has become a highly predictable treatment method. Despite this, related complications are on the rise, with peri-implant mucositis and peri-implantitis being the most commonly observed. As in the case of conventional periodontitis, many patients experience peri-implant mucositis and peri-implantitis. In this case presentation, extensive bone loss occurred around the implant due to peri-implantitis, and the infection was first treated by applying chlorhexidine-soaked gauze and topical antibiotics. Then the guided bone regeneration procedure was performed using a bovine bone material and a collagen membrane, which resulted in the recovery of the lesion. With follow-ups of the healing process for 30 months, a successful outcome was observed that is reported herein. PMID:23110578

Kim, Jong-Eun; Kim, Ha-Young; Huh, Jung-Bo; Lee, Jeong-Yol; Shin, Sang-Wan

2014-06-01

337

Fracture behaviour of implant–implant- and implant–tooth-supported all-ceramic fixed dental prostheses utilising zirconium dioxide implant abutments  

Microsoft Academic Search

This in vitro study investigated the fracture behaviour of implant–implant-supported and implant–tooth-supported all-ceramic\\u000a fixed dental prostheses (FDP) using zirconium dioxide implant abutments (FRIADENT® CERCON® abutments, DENTSPLY Friadent).\\u000a Six different test groups (n?=?8) were prepared. Groups 1, 2, 4, and 5 represented an implant–implant-supported FDP condition, whereas groups 3 and 6\\u000a simulated an implant–tooth-supported FDP condition. The second right premolar of

Frank Philipp Nothdurft; Sabine Merker; Peter Reinhard Pospiech

2011-01-01

338

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.

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

2013-01-01

339

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

340

Tissue Response to Peritoneal Implants.  

National Technical Information Service (NTIS)

Peritoneal implants were fabricated from poly 2-OH, ethyl methacrylate (HEMA), polyetherurethane (polytetramethylene glycol 1000 MW, 1,4 methylene disocynate, and ethyl diamine), and untreated and sputter treated polytetrafluoroethylene (PTFE). The sputte...

G. J. Picha

1980-01-01

341

Ion Implantation and Laser Annealing.  

National Technical Information Service (NTIS)

Three ion implantation and laser annealing projects have been performed by ORNL through the DOE sponsored Seed Money Program. The research has contributed toward improving the characteristics of wear, hardness, and corrosion resistance of some metals and ...

1986-01-01

342

Low Cost Implantation into Silicon.  

National Technical Information Service (NTIS)

The work outlined here concerns optimization of an ''ion incrustation technique'': implantation without mass separation, and pulsed annealing by YAG laser for production of junctions on silicon. The ion incrustation process is based on gas discharge in a ...

J. C. Muller P. Siffert

1985-01-01

343

Implantable Telemetry for Small Animals.  

National Technical Information Service (NTIS)

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 multich...

1982-01-01

344

Nanosurface - The Future of Implants  

PubMed Central

Nanotechnology is a relatively newer field of science that is finding enormous scope in the dental & medical science. Use of endosseous dental implant surfaces having nano-scale topography is fast becoming part of modern implantology. The purpose of this review is to discuss and understand the role of nanoscale surface modification of titanium materials for the purpose of improving various phases of implantology including osseointegration. Nanotechnology equips bioengineers with newer ways of interacting with relevant biological processes. On the other hand, the field of nanotechnology provides means of understanding and achieving cell specific functions. An understanding of the role of nano-topography leads to the significant osseointegration modulations by nanoscale modification of the implants surface. Use of nanotechnology to modify the topography of titanium endosseous implant can drastically improve cellular and tissue responses that may benefit osseointegration and dental implant procedures.

Thakral, Rashmi; Sharma, Neeraj; Seth, Jyotsana; Vashisht, Pallavi

2014-01-01

345

[Imaging in silicone breast implantation].  

PubMed

Recently, there have been concerns regarding the use of breast implants from Poly Implant Prothèse (PIP, Seyne sur Mer, France) for breast augmentation due to their tendency to rupture and the possibility of having toxic contents. MRI using a specific silicone-sensitive sequence has proven to be the most sensitive and specific technique in the detection of intra- and extracapsular implant rupture. However, given its high costs, it is important that this technique is used sparingly. In this clinical lesson, we compare the sensitivity and specificity of mammography, ultrasound, CT and MRI for the detection of breast implant rupture. Based on two cases, a diagnostic approach is given in order to reduce health care costs. PMID:24252405

Gielens, Maaike P M; Koolen, Pieter G L; Hermens, Roland A E C; Rutten, Matthieu J C M

2013-01-01

346

Implants for draining neovascular glaucoma.  

PubMed Central

The implant design, surgical technique, and pharmacological methods of controlling bleb fibrosis, used to treat neovascular glaucoma, are described, together with the results of 14 operations performed on 12 eyes. Images

Molteno, A C; Van Rooyen, M M; Bartholomew, R S

1977-01-01

347

Ion Implanted Silicon Solar Cells.  

National Technical Information Service (NTIS)

The theory of pn-junction silicon solar cells is thoroughly discussed including detailed deductions and calculations concerning the theoretical spectral response and the dark current in a solar cell with a back surface field. Ion implantation theory is re...

P. Balslev

1981-01-01

348

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

349

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

350

Cochlear implantations in Northern Ireland: an overview of the first five years.  

PubMed

During the last few years cochlear implantation (CI) has made remarkable progress, developing from a mere research tool to a viable clinical application. The Centre for CI in the Northern Ireland was established in 1992 and has since been a provider of this new technology for rehabilitation of profoundly deaf patients in the region. Although individual performance with a cochlear implant cannot be predicted accurately, the overall success of CI can no longer be denied. Seventy one patients, 37 adults and 34 children, have received implants over the first five years of the Northern Ireland cochlear implant programme, which is located at the Belfast City Hospital. The complication rates and the post-implantation outcome of this centre compare favourably with other major centres which undertake the procedure. This paper aims to highlight the patient selection criteria, surgery, post-CI outcome, clinical and research developments within our centre, and future prospects of this recent modality of treatment. PMID:10489806

John, G; Toner, J G

1999-05-01

351

Implant-retained auricular prosthesis.  

PubMed

Auricular defects may result from congenital malformations, injuries from motor vehicle crashes, trauma, or tumor resections. An auricular prosthesis was fabricated for a patient who had an injury from a motor vehicle crash. Extraoral implants and bar-and-clip retention for the proper connection of the auricular prosthesis to implant were used. This prosthesis was acceptable to the patient because of excellent support, retentive abilities, and the patient's appearance. PMID:21119423

Demir, Necla; Malkoc, Meral Arslan; Ozturk, A Nilgun; Tosun, Zekeriya

2010-11-01

352

Biologic effects of implant debris.  

PubMed

Biologic response to orthopedic implants debris is central to clinical performance. Eventual implant loosening due to aseptic osteolysis has been attributed to local inflammatory responses to wear and corrosion products that are produced by articulating implant interfaces. The response to implant debris is dominated by local immune activation, e.g. macrophages. Immune reactivity has been shown to depend on the number of particles produced or the dose (i.e., the concentration of phagocytosable particles per tissue volume, which can be characterized by knowing the size distribution and amount of debris). Elongated particles (fbers) are generally more pro-inflammatory than round particles, and there is a growing consensus that metals particles are more proinflammatory than polymers in vivo. Generally, to produce an in vitro inflammatory response, particles need to be less than 10 mum, i.e. phagocytosable. However, both soluble and particulate debris derived from Co-Cr-Mo alloy implants can induce monocyte/macrophage activation and secretion of pro-inflammatory cytokines such as IL-1beta, TNFalpha, IL-6 and IL-8 via up-regulation of transcription factor NFkappabeta, and activation of inflammasome danger signaling in human macrophages. Not only does activation of local (and systemic) inflammation result in decreased osteoblast function but osteoclast activity increases. Some people are more predisposed to implant debris induced inflammation and metal "allergy" testing services are becoming available. New pathways of implant debris-induced inflammatory reactions continue to be discovered, such as the "danger signaling" inflammasome pathway, which provides new targets for pharmaceutical intervention and improved implant performance. PMID:19583551

Hallab, Nadim J; Jacobs, Joshua J

2009-01-01

353

Pathology findings with acrylic implants  

Microsoft Academic Search

We report the pathological findings in cases of acrylic implants obtained by direct intratumoral injection of poly-methyl-methacrylate (PMMA) and N-butyl-cyano-acrylate (NBCA). Direct intratumoral injection of acrylic implants was performed for a variety of primary and secondary bone lesions. These types of treatments have been used at our institution in the last 4 years for 40 vertebroplasty (PMMA) procedures and for

D San Millán Ruíz; K Burkhardt; B Jean; M Muster; J. B Martin; J Bouvier; J. H. D Fasel; D. A Rüfenacht; A. M Kurt

1999-01-01

354

Optima XE Single Wafer High Energy Ion Implanter  

SciTech Connect

The Optima XE is the first production worthy single wafer high energy implanter. The new system combines a state-of-art single wafer endstation capable of throughputs in excess of 400 wafers/hour with a production-proven RF linear accelerator technology. Axcelis has been evolving and refining RF Linac technology since the introduction of the NV1000 in 1986. The Optima XE provides production worthy beam currents up to energies of 1.2 MeV for P{sup +}, 2.9 MeV for P{sup ++}, and 1.5 MeV for B{sup +}. Energies as low as 10 keV and tilt angles as high as 45 degrees are also available., allowing the implanter to be used for a wide variety of traditional medium current implants to ensure high equipment utilization. The single wafer endstation provides precise implant angle control across wafer and wafer to wafer. In addition, Optima XE's unique dose control system allows compensation of photoresist outgassing effects without relying on traditional pressure-based methods. We describe the specific features, angle control and dosimetry of the Optima XE and their applications in addressing the ever-tightening demands for more precise process controls and higher productivity.

Satoh, Shu; Ferrara, Joseph; Bell, Edward; Patel, Shital; Sieradzki, Manny [Axcelis Technologies, Inc. 108 Cherry Hill Drive, Beverly, MA 01915 (United States)

2008-11-03

355

Synthetic implants in hernia surgery.  

PubMed

Abdominal wall hernia correction is one of the most common surgical procedures. 85,000 hernia operations are performed in Poland each year. Modern techniques of abdominal wall reconstruction utilize surgical implants for fascial defect closure. In the 70s and the 80s of the last century, these techniques gained widespread acceptance among surgeons. Significant improvement of results in terms of recurrences was observed. Treatment of large abdominal wall defects became possible. Three types of surgical implants were developed early: polipropylene (PP), poliethylene (PE) and politetrafluoroethylene (PTFE). Unfortunately, negative effects of implanted material soon became apparent. Excessive native tissues inflammatory response to the implanted material, leading to multiple complications was observed. Recurrences due to fibrosis, chronic regional pain, stiffness of the operation site, intestinal adhesions and fistulas, infertility and infections were reported. In some cases the use of standard synthetic implant was contraindicated. Analyzing drawbacks of the standard hernia implants, the medical industry developed new materials to improve treatment results. The most popular, currently utilized synthetic materials, are presented in this review in the context of clinical results. PMID:24596016

Lukasiewicz, Aleksander; Drewa, Tomasz

2014-01-01

356

Body Implanted Medical Device Communications  

NASA Astrophysics Data System (ADS)

The medical care day by day and more and more is associated with and reliant upon concepts and advances of electronics and electromagnetics. Numerous medical devices are implanted in the body for medical use. Tissue implanted devices are of great interest for wireless medical applications due to the promising of different clinical usage to promote a patient independence. It can be used in hospitals, health care facilities and home to transmit patient measurement data, such as pulse and respiration rates to a nearby receiver, permitting greater patient mobility and increased comfort. As this service permits remote monitoring of several patients simultaneously it could also potentially decrease health care costs. Advancement in radio frequency communications and miniaturization of bioelectronics are supporting medical implant applications. A central component of wireless implanted device is an antenna and there are several issues to consider when designing an in-body antenna, including power consumption, size, frequency, biocompatibility and the unique RF transmission challenges posed by the human body. The radiation characteristics of such devices are important in terms of both safety and performance. The implanted antenna and human body as a medium for wireless communication are discussed over Medical Implant Communications Service (MICS) band in the frequency range of 402-405MHz.

Yazdandoost, Kamya Yekeh; Kohno, Ryuji

357

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

358

Reasons for failures of oral implants.  

PubMed

This study reviews the literature regarding the factors contributing to failures of dental implants. An electronic search was undertaken including papers from 2004 onwards. The titles and abstracts from these results were read to identify studies within the selection criteria. All reference lists of the selected studies were then hand-searched, this time without time restrictions. A narrative review discussed some findings from the first two parts where separate data from non-comparative studies may have indicated conclusions different from those possible to draw in the systematic analysis. It may be suggested that the following situations are correlated to increase the implant failure rate: a low insertion torque of implants that are planned to be immediately or early loaded, inexperienced surgeons inserting the implants, implant insertion in the maxilla, implant insertion in the posterior region of the jaws, implants in heavy smokers, implant insertion in bone qualities type III and IV, implant insertion in places with small bone volumes, use of shorter length implants, greater number of implants placed per patient, lack of initial implant stability, use of cylindrical (non-threaded) implants and prosthetic rehabilitation with implant-supported overdentures. Moreover, it may be suggested that the following situations may be correlated with an increase in the implant failure rate: use of the non-submerged technique, immediate loading, implant insertion in fresh extraction sockets, smaller diameter implants. Some recently published studies suggest that modern, moderately rough implants may present with similar results irrespective if placed in maxillas, in smoking patients or using only short implants. PMID:24612346

Chrcanovic, B R; Albrektsson, T; Wennerberg, A

2014-06-01

359

FISH for Pre-implantation Genetic Diagnosis  

PubMed Central

Pre-implantation genetic diagnosis (PGD) is an established alternative to pre-natal diagnosis, and involves selecting pre-implantation embryos from a cohort generated by assisted reproduction technology (ART). This selection may be required because of familial monogenic disease (e.g. cystic fibrosis), or because one partner carries a chromosome rearrangement (e.g. a two-way reciprocal translocation). PGD is available for couples who have had previous affected children, and/or in the case of chromosome rearrangements, recurrent miscarriages, or infertility. Oocytes aspirated following ovarian stimulation are fertilized by in vitro immersion in semen (IVF) or by intracytoplasmic injection of an individual spermatozoon (ICSI). Pre-implantation cleavage-stage embryos are biopsied, usually by the removal of a single cell on day 3 post-fertilization, and the biopsied cell is tested to establish the genetic status of the embryo. Fluorescence in situ hybridization (FISH) on the fixed nuclei of biopsied cells with target-specific DNA probes is the technique of choice to detect chromosome imbalance associated with chromosome rearrangements, and to select female embryos in families with X-linked disease for which there is no mutation-specific test. FISH has also been used to screen embryos for spontaneous chromosome aneuploidy (also known as PGS or PGD-AS) in order to try and improve the efficiency of assisted reproduction; however, the predictive value of this test using the spreading and FISH technique described here is likely to be unacceptably low in most people's hands and it is not recommended for routine clinical use. We describe the selection of suitable probes for single-cell FISH, spreading techniques for blastomere nuclei, and in situ hybridization and signal scoring, applied to PGD in a clinical setting.

Scriven, Paul N.; Kirby, Toby L.; Ogilvie, Caroline Mackie

2011-01-01

360

New advances in erectile technology.  

PubMed

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; Wang, Run

2014-02-01

361

Improving mechanical properties of polyethylene orthopaedic implants by high frequency cold plasma surface activation  

NASA Astrophysics Data System (ADS)

Although a tremendous progress has been made in developing new methods and materials for manufacturing orthopaedic implants, the new technology still faces various problems. Polyethylene implants are relatively easy to manufacture and at lower cost compared to metallic or ceramic implants, but they present a fundamental problem: during usage and in time, due to their manufacturing technology, the material suffers from pitting and delamination which leads to crack propagation and finally to sudden fracture. Our studies and tests performed on polyethylene showed that, using cold plasma surface activation during the manufacturing process of the orthopaedic implants made from polyethylene can significantly increase their mechanical properties. The breaking tests revealed an increase of the tensile strength in the laminated polyethylene samples by a factor of 4 after plasma activation. "Aging" tests have been also performed to investigate how the cold plasma treated samples maintain their properties in time, after the surface activation process.

Tudoran, Cristian D.; Vlad, Iulia E.; Dadarlat, Dorin N.; Anghel, Sorin D.

2013-11-01

362

[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

363

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

364

Impedance changes in chronically implanted and stimulated cochlear implant electrodes.  

PubMed

Objectives Electrode impedance increases following implantation and undergoes transitory reduction with onset of electrical stimulation. The studies in this paper measured the changes in access resistance and polarization impedance in vivo before and following electrical stimulation, and recorded the time course of these changes. Design Impedance measures recorded in (a) four cats following 6 months of cochlear implant use, and (b) three cochlear implant recipients with 1.5-5 years cochlear implant experience. Results Both the experimental and clinical data exhibited a reduction in electrode impedance, 20 and 5% respectively, within 15-30 minutes of stimulation onset. The majority of these changes occurred through reduction in polarization impedance. Cessation of stimulation was followed by an equivalent rise in impedance measures within 6-12 hours. Conclusions Stimulus-induced reductions in impedance exhibit a rapid onset and are evident in both chronic in vivo models tested, even several years after implantation. Given the impedance changes were dominated by the polarization component, these findings suggest that the electrical stimulation altered the electrode surface rather than the bulk tissue and fluid in the cochlea. PMID:23998484

Newbold, Carrie; Mergen, Silvana; Richardson, Rachael; Seligman, Peter; Millard, Rodney; Cowan, Robert; Shepherd, Robert

2014-07-01

365

Investigation of nitrogen and carbon co-implantation under room temperature and cryo-condition  

NASA Astrophysics Data System (ADS)

Co-implantation of non-dopant species is widely used in 65nm and beyond Complementary Metal-Oxide-Semiconductor (CMOS) technology node to meet ITRS ultra shallow junction roadmap and device performance requirement. With co-implantation, non-dopant species, such as Carbon (C), Fluorine (F) and Nitrogen (N), can either suppress doping diffusion or modify material property and improve device reliability. Cold implantation with wafer pedestal cooling to near -100°C is another hot topic in CMOS manufacture recently. It has obvious benefits, such as good amorphization performance, less end of range defect, less stress relaxation especially for e-SiGe formation. In the present work, different co-implantations with nitrogen and/or carbon were investigated for advanced NMOS Lightly Doped Drain (LDD) junction formation. The co-implantation was performed under room temperature or -100°C. It was found that C or C plus N co-implantations are very effective to suppress the diffusion of halo-implanted boron. Comparing with room temperature, the cryo-implantation under -100°C can get much better amorphization and less End of Range (EOR) defects, which result in reduced junction leakage and high activation as observed on blanket wafer and device wafers.

He, Yonggen; Wu, Bing; Yu, Guobin; Chen, Yong; Liu, Hailong; He, Youfeng; Dai, Haibo; Wu, Jingang; Zhang, David Wei; Lu, Junfeng; Xu, Jingrui; Guo, Baonian

2012-11-01

366

Transcatheter aortic valve implantation: what has been done and what is going to be done.  

PubMed

Transcatheter valve implantation is developing into an effective and reproducible therapy for aortic valve stenosis. The origin of this technique was pursued in 1992 when Andersen demonstrated the feasibility of percutaneous implantation of catheter-based valve prosthesis. Since then a lot of technical and device advances have been made and to date, transcatheter aortic valve implantation has became a concrete alternative to surgical replacement. This paper aims to go over all the current devices, from the most widely used to the newest technology, focusing on device description, procedural issues, potential complications and clinical studies currently available in literature. PMID:20014989

Tamburino, Corrado; Barbanti, Marco; Capodanno, Davide; Ussia, Gian Paolo

2010-01-01

367

Shape memory effect and superelasticity of titanium nickelide alloys implanted with high ion doses  

NASA Astrophysics Data System (ADS)

The state of the art in ion implantation of superelastic NiTi shape memory alloys is analyzed. Various technological applications of the shape memory effect are outlined. The principles and techiques of ion implantation are described. Specific features of its application for modification of surface layers in surface engineering are considered. Key properties of shape memory alloys and problems in utilization of ion implantation to improve the surface properties of shape memory alloys, such as corrosion resistance, friction coefficient, wear resistance, etc. are discussed. The bibliography includes 162 references.

Pogrebnjak, A. D.; Bratushka, S. N.; Beresnev, V. M.; Levintant-Zayonts, N.

2013-12-01

368

Modern metal-on-metal hip implants.  

PubMed

This Technology Overview was prepared using systematic review methodology and summarizes the findings of studies published as of July 15, 2011, on modern metal-on-metal hip implants. Analyses conducted on outcomes by two joint registries indicate that patients who receive metal-on-metal total hip arthroplasty (THA) and hip resurfacing are at greater risk for revision than are patients who receive THA using a different bearing surface combination. Data from these registries also indicate that larger femoral head components have higher revision rates and risk of revision and that older age is associated with increased revision risks of large-head metal-on-metal THA. Several studies noted a correlation between suboptimal hip implant positioning and higher wear rates, local metal debris release, and consequent local tissue reactions to metal debris. In addition, several studies reported elevated serum metal ion concentrations in patients with metal-on-metal hip articulations, although the clinical significance of these elevated ion concentrations remains unknown. PMID:22661570

Bozic, Kevin J; Browne, James; Dangles, Chris J; Manner, Paul A; Yates, Adolph J; Weber, Kristy L; Boyer, Kevin M; Zemaitis, Paul; Woznica, Anne; Turkelson, Charles M; Wies, Janet L

2012-06-01

369

Characterizations of additive manufactured porous titanium implants.  

PubMed

This article describes physical, chemical, and mechanical characterizations of porous titanium implants made by an additive manufacturing method to gain insight into the correlation of process parameters and final physical properties of implants used in orthopedics. For the manufacturing chain, the powder metallurgy technology was combined with the additive manufacturing to fabricate the porous structure from the pure tanium powder. A 3D printing machine was employed in this study to produce porous bar samples. A number of physical parameters such as titanium powder size, polyvinyl alcohol (PVA) amount, sintering temperature and time were investigated to control the mechanical properties and porosity of the structures. The produced samples were characterized through porosity and shrinkage measurements, mechanical compression test and scanning electron microscopy (SEM). The results showed a level of porosity in the samples in the range of 31-43%, which is within the range of the porosity of the cancelluous bone and approaches the range of the porosity of the cortical bone. The results of the mechanical test showed that the compressive strength is in the wide range of 56-509 MPa implying the effect of the process parameters on the mechanical strengths. This technique of manufacturing of Ti porous structures demonstrated a low level of shrinkage with the shrinkage percentage ranging from 1.5 to 5%. PMID:22865677

Basalah, Ahmad; Shanjani, Yaser; Esmaeili, Shahrzad; Toyserkani, Ehsan

2012-10-01

370

Drug-eluting medical implants.  

PubMed

Drug-eluting medical implants are actually active implants that induce healing effects, in addition to their regular task of support. This effect is achieved by controlled release of active pharmaceutical ingredients (API) into the surrounding tissue. In this chapter we focus on three types of drug-eluting devices: drug-eluting vascular stents, drug-eluting wound dressings and protein-eluting scaffolds for tissue regeneration, thus describing both internal and external implants. Each of these drug-eluting devices also presents an approach for solving the drug release issue. Most drug-eluting vascular stents are loaded with water-insoluble antiproliferative agents, and their diffusion from the device to the surrounding tissue is relatively slow. In contrast, most drug-eluting wound dressings are loaded with highly water-soluble antibacterial agents and the issue of fast release must therefore be addressed. Growth factor release from scaffolds for tissue regeneration offers a new approach of incorporating high-molecular-weight bioactive agents which are very sensitive to process conditions and preserve their activity during the preparation stage. The drug-eluting medical implants are described here in terms of matrix formats and polymers, incorporated drugs and their release profiles from the implants, and implant functioning. Basic elements, such as new composite core/shell fibers and structured films, can be used to build new antibiotic-eluting devices. As presented in this chapter, the effect of the processing parameters on the microstructure and the resulting drug release profiles, mechanical and physical properties, and other relevant properties, must be elucidated in order to achieve the desired properties. Newly developed implants and novel modifications of previously developed approaches have enhanced the tools available for creating clinically important biomedical applications. PMID:20217535

Zilberman, Meital; Kraitzer, Amir; Grinberg, Orly; Elsner, Jonathan J

2010-01-01

371

Evaluation and integration of a new gas source package for boron trifluoride used in ion implantation  

Microsoft Academic Search

A new reduced risk packaging technology for boron trifluoride gas was tested at Agere Systems MOS 5 (formerly Lucent Technologies) Allentown, Pa. semiconductor fabrication facility. Produced by ATMI, Inc. of Danbury, Ct. the VAC™ package allows for high capacity storage of corrosive and flammable gases while dispensing only at sub-atmospheric pressure for the ion implant application. This paper reports the

D. J. Mckee; L. J. Van Horn

2002-01-01

372

Wear resistance of plasma immersion ion implanted Ti6Al4V  

Microsoft Academic Search

The plasma immersion ion implantation (PI3tm) process has been employed in the treatment of the Ti6Al4V alloy in order to improve its notoriously poor tribological properties. In particular, this study was undertaken with a view to its potential application for the surface engineering of orthopaedic implants.PI3 has been developed over recent years at the Australian Nuclear Science and Technology Organisation

S. M. Johns; T. Bell; M. Samandi; G. A. Collins

1996-01-01

373

Indium channel implant for improved short-channel behavior of submicrometer NMOSFETs  

Microsoft Academic Search

Indium has been used as an alternative channel implant in submicrometer-channel Si MOSFETs in order to obtain highly nonuniform channel doping. Superior device characteristics have been obtained down to 0.17-?m channel length. The device characteristics have been compared to those of uniform boron-implanted short-channel MOSFETs used in a 0.25-?m CMOS technology. Results indicate that NMOSFETs with nonuniform channel doping obtained

G. G. Shahidi; Bijan Davari; Thomas J. Bucelot; P. A. Ronsheim; P. J. Coane; S. Pollack; C. R. Blair; B. Clark; Howard H. Hansen

1993-01-01

374

Superior latch-up resistance of high dose, high energy implanted p + buried layers  

Microsoft Academic Search

Implantation of high dose, high energy blanket boron buried layers into p-type silicon is becoming increasingly attractive for leading edge CMOS technology. Implanted p+ buried layers provide several device and circuit benefits, such as superior latch-up immunity as compared to thin epi, and secondary defect gettering of other point defects. We have demonstrated that a 1×1015 cm-2 1.7 MeV boron

K. C. Leong; P. C. Liu; W. Morris; L. Rubin; C. H. Gan; L. Chan

1999-01-01

375

Biocompatible benzocyclobutene (BCB)-based neural implants with micro-fluidic channel  

Microsoft Academic Search

Poly-benzocyclobutene (BCB)-based intracortical neural implant was fabricated, in which micro-fluidic channel was embedded to deliver drug solutions. BCB presents several attractive features for chronic applications: flexibility, biocompatibility, desirable chemical and electrical properties, and can be easily manufactured using existing batch micro-fabrication technology. The fabricated implants have single shank with three recording sites (20?m×20?m) and two reserviors (inlet and outlet). The

Keekeun Lee; Jiping He; Ryan Clement; Stephen Massia; Bruce Kim

2004-01-01

376

Experience and Evaluation of a New, Saline-Filled Implant for Cosmetic Lip Augmentation  

Microsoft Academic Search

purpose of this article is to discuss the author's experience with a new saline-filled lip implant technology in an initial series of patients. Materials and Methods: The novel saline-fillable implant (VeraFil; Evera Medical) is composed of a thin expanded polytetrafluoroethylene outer membrane bonded, only at the ends of the device, to a silicone inner membrane creating a slip plane between

Joe Niamtu

377

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

378

Endoscopic cochlear implant procedure.  

PubMed

The objective was to asses the feasibility of the endoscopic technique for cochlear implant (CI) positioning avoiding mastoidectomy and to discuss the benefits and drawbacks of the technique. The study design is a surgical procedure description and prospective case series report. From December 2011 to October 2012, six patients underwent endoscopic CI. All cases were selected based on CT and MRI studies. All surgical steps were analyzed; intra-and post-operative complications were noted. The length of time for each surgical procedure was recorded. The surgical procedure was described step by step focusing on the anatomy of the round window (RW) niche, analyzing the critical point during the dissection. The timing of the surgical procedures was 120 ± 21 (mean ± SD) min. In 1/6 patients, intra-operative injury of the chorda tympani occurred. In all cases, an endoscopic identification was performed and the anatomical details of the RW niche were noted. In 6/6 cases, a RW niche magnification was performed endoscopically. 5/6 cases showed a normal conformation of the RW. In 1/6 patients, obliteration of the RW niche was found. In 4/6 patients, an endoscopic cochleostomy through the RW was performed. In 1/6 patients, a difficult insertion of the array was observed. The current follow-up is 7.3 months (SD ± 3.7). No post-operative short- or long-term complications were noted in this series. Endoscopic CI is a safe and viable technique with a low rate of complications and with good outcomes. PMID:23595616

Marchioni, Daniele; Grammatica, Alberto; Alicandri-Ciufelli, Matteo; Genovese, Elisabetta; Presutti, Livio

2014-05-01

379

Surface biotechnology for refining cochlear implants.  

PubMed

The advent of the cochlear implant is phenomenal because it is the first surgical prosthesis that is capable of restoring one of the senses. The subsequent rapid evolution of cochlear implants through increasing complexity and functionality has been synchronized with the recent advancements in biotechnology. Surface biotechnology has refined cochlear implants by directly influencing the implant–tissue interface. Emerging surface biotechnology strategies are exemplified by nanofibrous polymeric materials, topographical surface modification, conducting polymer coatings, and neurotrophin-eluting implants. Although these novel developments have received individual attention in the recent literature, the time has come to investigate their collective applications to cochlear implants to restore lost hearing. PMID:24404581

Tan, Fei; Walshe, Peter; Viani, Laura; Al-Rubeai, Mohamed

2013-12-01

380

Investigation on plasma immersion ion implantation treated medical implants.  

PubMed

In this work the biocompatibility of osteosynsthesis plates treated with plasma immersion ion implantation (PIII) was tested using a rat model. Small rods (Ø 0.9 mm, and length 10 mm) prepared from different materials-pure Ti, anodised Ti, and two NiTi alloys (SE 508, and SM 495)-were implanted with oxygen by PIII to form a rutile surface layer and subsequently inserted into rat femurs, together with a control group of untreated samples. The results of the biomechanical tests correlate with the histological results, and show that plasma immersion ion implantation leads to an increase of biocompatibility and osseointegration of titanium and NiTi, albeit no improvement of the (bad) biocompatibility of the anodised Ti. Despite the layer thickness of up to 0.5 microm a strong influence of the base material is still present. PMID:12202173

Mändl, S; Sader, R; Thorwarth, G; Krause, D; Zeilhofer, H-F; Horch, H H; Rauschenbach, B

2002-08-01

381

Generator and Lead-Related Complications of Implantable Cardioverter Defibrillators  

PubMed Central

Background: Increase in the number of patients treated with Implantable Cardioverter Defibrillator (ICD) requests more attention regarding its complications. Objectives: This study aimed to assess the generator- and lead-related complications at implantation and during follow-up in the patients who were treated with ICD for primary and secondary prevention reasons. Methods: We retrospectively reviewed 255 consecutive patients who underwent transvenous ICD implantation for the first time in a 7-year period and were followed-up for 3 years at Tehran Heart Center. The personal and clinical data of the patients as well as specific data on the ICD implantation were retrieved. The frequency of each of the complications was reported and the study variables were compared between the patients with and without complications using Student’s t-test and chi-square test where appropriate. P values less than 0.05 were considered as statistically significant. Results: Out of a total of 525 implanted leads and 255 implanted devices in 255 patients (mean age = 62.57 ± 13.50 years; male = 196 [76.9%]), complications leading to generator or lead replacement occurred in 32 patients (12.5%). The results revealed no significant difference between the patients with and without complications regarding gender and age (P = 0.206 and P = 0.824, respectively). Also, no significant difference was found between the two groups concerning the ejection fraction (P = 0.271). Lead fracture was the most frequent lead-related complication and was observed in 17 patients (6.6%). Besides, it was mainly observed in the RV leads. Generator-related complications leading to generator replacement were observed in 2 patients (0.7%). Conclusions: Despite considerable improvements in the ICD technology, the rate of the ICD complications leading to device replacement and surgical revision, especially those related to the leads, is still clinically important.

Yaminisharif, Ahmad; Soofizadeh, Nader; Shafiee, Akbar; Kazemisaeid, Ali; Jalali, Arash; Vasheghani-Farahani, Ali

2014-01-01

382

Multimodality Noninvasive Imaging for Transcatheter Aortic Valve Implantation: A primer  

PubMed Central

Transcatheter aortic valve implantation (TAVI) has recently emerged as a treatment option for patients with severe aortic valve stenosis (AS). For patients who are deemed inoperable for surgical aortic valve replacement (SAVR), TAVI has a significant mortality benefit compared to medical therapy. This review discusses established and emerging roles for multimodality imaging and focuses on the application of these technologies for patient selection, intraprocedural guidance, and the detection and quantification of acute and chronic complications of this novel procedure.

Shah, Dipan J.; Mahmarian, John J.

2012-01-01

383

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.

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

2012-01-01

384

Keratoprosthesis. Implantation of artificial corneas.  

PubMed

Keratoprosthesis (implantation of artificial, plastic cornea) is indicated in severe cases with corneal leucoma (non-transparent, cicatrized cornea) in which keratoplasty (corneal transplantation) is not possible or has repeatedly failed. In the past 40 years we implanted 37 artificial corneas (7 Cardona type, 29 Konstantinov type, 1 Fjodorov type). The visual acuity increase was temporary (lasting from a few weeks to a few months) in 25 patients. The visual acuity was at least 0.2 three years following the implantation of keratoprosthesis in 12 patients. One patient had 1.0 vision 10 years after surgery. Our results indicate that the implantation of artificial corneal is still an "ultimum refugium", an operation that can be justified only in monocular patients, in eyes that cannot be and/or had unsuccessfully been operated on with repeated keratoplasties. The visual improvement is temporary, but in some cases may last for several years. Still this is the only procedure by which useful vision can be provided, for shorter or longer time intervals, for patients suffering from corneal blindness (nontransparent cornea in otherwise functioning eye) whose only eye cannot be treated with corneal transplantation. Keratoprosthesis with better biocompatibility, better fixation techniques, and wider visual fields have to be developed before the implantation of artificial cornea can be looked upon as a surgical procedure with which full optical rehabilitation can be achieved. PMID:9408276

Berta, A

1997-01-01

385

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.

Thevenot, Paul; Hu, Wenjing; Tang, Liping

2011-01-01

386

Rhenium ion beam for implantation into semiconductors  

SciTech Connect

At the ion source test bench in Institute for Theoretical and Experimental Physics the program of ion source development for semiconductor industry is in progress. In framework of the program the Metal Vapor Vacuum Arc ion source for germanium and rhenium ion beam generation was developed and investigated. It was shown that at special conditions of ion beam implantation it is possible to fabricate not only homogenous layers of rhenium silicides solid solutions but also clusters of this compound with properties of quantum dots. At the present moment the compound is very interesting for semiconductor industry, especially for nanoelectronics and nanophotonics, but there is no very developed technology for production of nanostructures (for example quantum sized structures) with required parameters. The results of materials synthesis and exploration are presented.

Kulevoy, T. V.; Seleznev, D. N.; Alyoshin, M. E.; Kraevsky, S. V.; Yakushin, P. E.; Khoroshilov, V. V. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Gerasimenko, N. N.; Smirnov, D. I. [National Research University of Electronic Technology ''MIET'', Moscow (Russian Federation); Fedorov, P. A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); National Research University of Electronic Technology ''MIET'', Moscow (Russian Federation); Temirov, A. A. [National University of Science and Technology ''MISIS'', Moscow (Russian Federation)

2012-02-15

387

Programmable Implantable Medication System: Its Applications to Diabetes.  

National Technical Information Service (NTIS)

In Year 03, animal work has continued to lay the basis for human implantation of the Implantable, Programmable Infusion Pump (IPIP), the implanted component of PIMS. The authors did not progress to the point of human implantation because technical obstacl...

C. D. Saudek

1984-01-01

388

Electrical Activation Studies of Ion Implanted Gallium Nitride.  

National Technical Information Service (NTIS)

A comprehensive and systematic electrical activation study of Si- implanted GaN was performed as a function of ion implantation dose, anneal temperature, and implantation temperature. Additionally, Mg-implanted GaN was also investigated. Temperature-depen...

J. A. Fellows

2001-01-01

389

Tinting of intraocular lens implants  

SciTech Connect

Intraocular lens (IOL) implants of polymethyl methacrylate (PMMA) lack an important yellow pigment useful as a filter in the visual process and in the protection of the retina from short-wavelength radiant energy. The ability to produce a yellow pigment in the PMMA used in IOL implants by exposure to near-ultraviolet (UV) light was tested. It was found that the highly cross-linked material in Copeland lens blanks was tinted slightly because of this exposure. The absorptive properties of lens blanks treated with near-UV light in this way approached that of the absorptive properties of human lenses. This finding shows that it is possible to alter IOL implants simply so as to induce a pale-yellow pigment in them to improve the visual process and to protect the retinas of IOL users.

Zigman, S.

1982-06-01

390

Implant rehabilitation in bruxism patient.  

PubMed

A white female patient presented to the university clinic to obtain implant retained prostheses. She had an edentulous maxillary jaw and presented three teeth with poor prognosis (33, 34 and 43). The alveolar bone and the surrounding tissues were healthy. The patient did not report any relevant medical history contraindicating routine dental treatment or implant surgery, but self-reported a dental history of asymptomatic nocturnal bruxism. The treatment plan was set and two Branemark protocols supported by six implants in each arch were installed after a 6-month healing period. A soft occlusal splint was made due to the patient's history of bruxism, and the lack of its use by the patient resulted in an acrylic fracture. The prosthesis was repaired and the importance of using the occlusal splint was restated. In the 4-year follow-up no fractures were reported. PMID:24907215

Goiato, Marcelo Coelho; Sonego, Mariana Vilela; Dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas

2014-01-01

391

MRI artefacts after Bonebridge implantation.  

PubMed

The new transcutaneous bone conduction implant (BCI) Bonebridge (BB, MED-EL) allows the skin to remain intact and therefore overcomes some issues related to percutaneous systems, such as skin reaction around the external screw and cosmetic complaints. According to manufacturer, BB is MRI conditional up to 1,5 Tesla (T). The artefact of the neurocranium after BB implantation is extensive as shown in the present report. This has to be taken into account when patients suffering conductive, mixed or single-sided hearing loss with candidacy for a BCI are counselled. In patients with comorbid intracranial tumour or other diseases of the brain that require imaging control scans with MRI percutaneous, BCI should be the implant of choice considering the very small artefact of the percutaneous screw in MRI. PMID:24639341

Steinmetz, C; Mader, I; Arndt, S; Aschendorff, A; Laszig, R; Hassepass, F

2014-07-01

392

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.

2011-01-01

393

Electrochemical Properties of Ion Implanted Silicon.  

National Technical Information Service (NTIS)

The electrochemical behaviour of ion implanted silicon in contact with hydrofluoric acid solution was investigated. It was shown that the implanted layer on silicon changes profoundly its electrochemical properties (photopotential, interface impedance, re...

Pham minh Tan

1979-01-01

394

Surgical Tooth Implants, Combat and Field.  

National Technical Information Service (NTIS)

Long term implant studies of alumina tooth roots are being performed in both humans and baboons. The implants designed for this project are a single root rectangular design with serrations arranged for maximal stress distribution of occlusal loads. THe im...

C. R. Hassler R. M. Downes L. G. McCoy

1981-01-01

395

Surgical Tooth Implants, Combat and Field.  

National Technical Information Service (NTIS)

Long term implant studies of alumina tooth roots are being performed in both humans and baboons. The implants designed for this project are single root elliptical and rectangular designs with serrations arranged for maximal stress distribution of occlusal...

C. R. Hassler R. M. Downes G. L. Messing O. E. Russell

1979-01-01

396

Surgical Tooth Implants, Combat and Field.  

National Technical Information Service (NTIS)

Long term implant studies of alumina tooth roots are being performed on both humans and baboons. The implants designed for this project are a single root rectangular design with serrations arranged for maximal stress distribution of occlusal loads. The im...

C. R. Hassler L. G. McCoy N. E. Arlin

1983-01-01

397

Surgical Tooth Implants, Combat and Field.  

National Technical Information Service (NTIS)

Long term implant studies of alumina tooth roots are being performed in both humans and baboons. The implants designed for this project are a single root rectangular design with serrations arranged for maximal stress distribution of occlusal loads. The im...

C. R. Hassler R. M. Downes L. G. McCoy

1982-01-01

398

Assessment of Implantation in the Rat.  

National Technical Information Service (NTIS)

A series of protocols has been assembled and used for the assessment of implantation failure following chemical exposure in the rat. Upon detecting a chemically-induced blockade of implantation, these protocols are designed to probe the physiological mech...

A. M. Cummings

1991-01-01

399

Mechanical Properties of Ion Implanted Ceramics.  

National Technical Information Service (NTIS)

The surface mechanical properties of ceramics are altered by ion implantation. The alteration results from the microstructural changes and the residual stresses produced in the implanted zone. Because of difficulties associated with accurate property dete...

C. J. McHargue

1988-01-01

400

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

401

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

402

Surgical Tooth Implants, Combat and Field.  

National Technical Information Service (NTIS)

Studies have been conducted concerning the development of improved, high-density, high-strength grooved alumina tooth root structures of the nonbifurcated design for monkey and human implant studies. Biomechanical stabilization of the implants in a tooth ...

C. R. Hassler, T. D. Driskell, L. G. McCoy, D. E. Niesz

1974-01-01

403

Interstitial IR192 implants of the oral cavity: the planning and construction of volume implants  

Microsoft Academic Search

The success of radioactive implant therapy for head and neck carcinomas depends critically on careful planning and execution of the implant procedure. In this paper we discuss our experience with oral tongue and floor of mouth implants, and some innovations introduced to facilitate these procedures. Implants were carried out using standard angiocatheters modified with magnetic caps at the open end

R. Schmidt-Ullrich; R. D. Zwicker; A. Wu; Kathleen Kelly

1991-01-01

404

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

405

Augmentation mammaplasty using implants: a review.  

PubMed

One of the techniques for augmentation mammaplasty is the procedure using implants. Even though this technique has been used for many years, there are still several controversial issues to be discussed and overcome for patient safety. In this review article, capsular contracture, leak or rupture of the implants, possible systemic disease, relation with breast cancer, and recent problems with Poly Implant Prothese implants are described and discussed. PMID:23094237

Takayanagi, Susumu

2012-09-01

406

Augmentation Mammaplasty Using Implants: A Review  

PubMed Central

One of the techniques for augmentation mammaplasty is the procedure using implants. Even though this technique has been used for many years, there are still several controversial issues to be discussed and overcome for patient safety. In this review article, capsular contracture, leak or rupture of the implants, possible systemic disease, relation with breast cancer, and recent problems with Poly Implant Prothese implants are described and discussed.

2012-01-01

407

Positron annihilation study of P implanted Si  

SciTech Connect

High-energy ion implantation (above 200 keV) is now commonly used in a variety of VLSI processes. The high energy required for these implants is often achieved by implanting multiply charged ions, which inevitably brings in the problem of low-energy ion contamination. The low-energy contamination is difficult to diagnose and detect. Positron annihilation spectroscopy is used to examine the defect distributions in these high energy implants with varying degrees of contamination.

Asoka-Kumar, P.; Au, H.L.; Lynn, K.G. (Brookhaven National Lab., Upton, NY (United States)); Sferlazzo, P. (Eaton Corp., Beverly, MA (United States). SED Division)

1992-01-01

408

Positron annihilation study of P implanted Si  

SciTech Connect

High-energy ion implantation (above 200 keV) is now commonly used in a variety of VLSI processes. The high energy required for these implants is often achieved by implanting multiply charged ions, which inevitably brings in the problem of low-energy ion contamination. The low-energy contamination is difficult to diagnose and detect. Positron annihilation spectroscopy is used to examine the defect distributions in these high energy implants with varying degrees of contamination.

Asoka-Kumar, P.; Au, H.L.; Lynn, K.G. [Brookhaven National Lab., Upton, NY (United States); Sferlazzo, P. [Eaton Corp., Beverly, MA (United States). SED Division

1992-12-01

409

Ion implantation of superhard ceramic cutting tools  

Microsoft Academic Search

Despite numerous reports of tool life increase by ion implantation in machining operations, ion implantation applications\\u000a of cutting tools remain limited, especially for ceramic tools. Mechanisms of tool-life improvement by implantation are not\\u000a clearly established due to complexity of both implantation and tool-wear processes. In an attempt to improve performance of\\u000a cubic boron nitride (CBN) tools for hard machining by

Y. Kevin Chou; Jie Liu

2004-01-01

410

Update on retinal prosthetic research: the Boston Retinal Implant Project.  

PubMed

The field of retinal prosthetic research, now more than 20 years old, has produced many high-quality technical options that have the potential to restore vision to patients with acquired disease of the outer retina. Five companies have performed Phase I clinical trials demonstrating that blind patients can reliably report basic elements of visual percepts induced by electrical stimulation. However, at present patients and observers generally do not consider the results to be useful enough in the performance of tasks of daily living to justify the risks of surgery and chronic implantation or the costs. Having developed a wireless device implanted in the subretinal space, the Boston Retinal Implant Project has focused its efforts on developing scalable technologies to create a hermetic device that can deliver individually controlled pulses of electrical stimulation to each of hundreds of electrodes. An advanced device with such attributes will be needed to justify the risks of implantation. An assessment of long-term biocompatibility for all devices remains to be done. PMID:21593628

Rizzo, Joseph F

2011-06-01

411

Implantable electrode lead in a growing limb  

Microsoft Academic Search

An implantable electrode leadwire system used to provide limb function for individuals with spinal cord injuries (SCI's) was evaluated in a series of growing dogs to determine whether it could maintain its performance in the presence of growth. Thirty implantable electrodes (15 epimysial and 15 intramuscular) were implanted in the forelimb muscles of 6 young dogs. The electrodes' leads were

June M. Akers; Brian T. Smith; Randal R. Betz

1999-01-01

412

Dental implant installation without antibiotic prophylaxis  

Microsoft Academic Search

The objective of this study was to retrospectively compare the outcomes of dental implant treatment with and without antibiotic prophylaxis. Two groups of patients with edentulous or partially edentulous maxillas or mandibles (or both) were treated with dental implants. One group, consisting of 147 patients (790 implants), was given prophylaxis with oral phenoxymethylpenicillin; 1 g of antibiotic was administered 1

Göran W Gynther; Per Åke Köndell; Lars-Erik Moberg; Anders Heimdahl

1998-01-01

413

Ion Implantation of Two Titanium Alloys.  

National Technical Information Service (NTIS)

Samples of two titanium alloys, Ti-6Al-4V and Ti-15V-3Cr-3Sn-3Al, were ion implanted with a combination of nitrogen (N(sup (plus))) and oxygen (O(sup (plus))). For each alloy, implantation parameters were chosen to give implanted nitrogen concentrations o...

B. D. Barton T. N. Wittberg

1989-01-01

414

Clinical testing of implanted pacemakers  

Microsoft Academic Search

The function of implanted pacemakers was assessed at a special pacemaker clinic at intervals of three to six months. Measurements of the basic discharge rate of the pacemaker were made and the waveform was recovered from skin electrodes and displayed on an oscilloscope screen. The impulse was photographed from the screen and subsequent waveform analysis was carried out. Reproducible results

Edgar Sowton; Kenneth Gray

1971-01-01

415

Pre-implantation genetic diagnosis  

Microsoft Academic Search

Pre-implantation genetic diagnosis is an alternative to prenatal diagnosis for a select group of patients. Patients have to go through in vitro fertilization in order to produce embryos in vitro, from which one or two cells are removed at the 8-cell stage. A fluorescence in situ hybridization or polymerase chain reaction is carried out for the genetic diagnosis. Fluorescence in

Joyce C Harper

2002-01-01

416

Ion implantation doping of diamond  

SciTech Connect

The introduction by ion implantation of electrical dopants into single crystal diamond for the formation of an extrinsic semiconductor has been studied. RBS/channeling and optical absorption have been used to study the radiation damage produced by implantation of carbon ions into single crystal diamond. Damage recovery by thermal annealing has been measured as a function of dose, anneal temperature, and anneal rate. Three dose dependent effects have been observed in the annealed samples. At low dose, recovery of the crystal structure was possible when annealed above 900[degrees]C. At high dose, sufficient amorphization caused a conversion to graphite upon annealing at high temperature. In a medium dose range, a thermally stable damage region was formed at 800[degrees]C which showed no channeling but did not convert to graphite. The results of the annealing studies were applied to minimize the damage accompanying the implantation of boron (p-type), sodium (n-type), and other dopants into single crystal diamond. Implantation of boron successfully reproduced the semiconducting behavior observed in natural, boron doped, semiconducting diamond. A single electrical activation energy of 0.32 eV has been measured over a broader temperature range than previously observed. N-type doping with suitable species has also been attempted. Exponentially activated conduction has been observed but thermal instability points to a damage related mechanism.

Hunn, J.D.

1992-01-01

417

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

418

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.

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

2013-01-01

419

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

420

Implant Surfaces and Interface Processes  

Microsoft Academic Search

The past decades and current R&D of biomaterials and medical implants show some general trends. One major trend is an increased degree of functionalization of the material surface, better to meet the demands of the biological host system. While the biomaterials of the past and those in current use are essentially bulk materials (metals, ceramics, polymers) or special compounds (bioglasses),

B. Kasemo; J. Gold

1999-01-01

421

Facial skeletal reconstruction using porous polyethylene implants.  

PubMed

A retrospective review of clinical outcomes was performed to determine the clinical utility and morbidity associated with the use of porous polyethylene facial implants. Three hundred seventy implants were placed in 162 consecutive patients, in 178 operations performed in 11 years. The number of patients, the number of implants used, and the average follow-up period were categorized according to the cause of the deformity. The resultant distribution was as follows: acquired (tumor-related), 17 patients, 39 implants, and 30 months; congenital, eight patients, 31 implants, and 92 months; aesthetic, 39 patients, 97 implants, and 24 months; secondary posttraumatic, 48 patients, 139 implants, and 37 months; and acute trauma (internal orbit reconstruction), 50 patients, 64 implants, and 9 months. The distribution of implants according to location was as follows: frontal, 21; temporal, 30; internal orbit, 145; infraorbital rim, 28; malar, 58; paranasal, 29; nasal, 13; mandible, 24; and chin, 22. The combined average follow-up period per patient was 27 months (range, immediate postoperative period to 11 years). All implants were placed in the subperiosteal plane, and the majority were fixed with titanium screws. Antibiotics were administered perioperatively. No implants were extruded or migrated, formed clinically apparent capsules, or caused symptoms attributable to bioincompatibility. The overall reoperation rate was 10 percent (n = 16), which included operations to remove implants because of acute infections (2 percent, n = 3) or a late infection (1 percent, n = 1), to remove implants causing displeasing contours (2 percent, n = 3), and to improve contours (6 percent, n = 9). Porous polyethylene implants have biomaterial properties favorable for facial skeletal augmentation. Screw application of the implants to the skeleton allows precise predictable contouring, thus limiting the need for revisional surgical procedures. PMID:12711941

Yaremchuk, Michael J

2003-05-01

422

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

423

Characterization of Charging Control of a Single Wafer High Current Spot Beam Implanter  

SciTech Connect

This paper focuses on the characterization of charging control of an Axcelis Optima HD single wafer high current spot beam implanter using MOS capacitors with attached antennas of different size and shape. Resist patterns are implemented on Infineon Technologies own charging control wafers to investigate the influence of photo resist on charging damage. Compared to batch high current implanters the design of the beamline and the beam shape are comparable to single wafer high current spot beam implanters, however due to the different scanning architecture the dose rate of the single wafer high current spot beam implanters is significantly higher compared to the batch tools. Therefore, the risk of charging damage will be higher. The charging damage was studied as a function of the energy, the beam current and the most important plasma flood gun parameters. The results have shown that for very high antenna ratios the charging damage for single wafer implanters, even spot or ribbon beam implanters, is higher than for high current batch implanters.

Schmeide, Matthias; Bukethal, Christoph [Infineon Technologies Dresden GmbH and Co. OHG, Koenigsbruecker Str. 180, D-01099 Dresden (Germany)

2008-11-03

424

Growth of YBa2Cu3O7-? on Co implanted substrates  

NASA Astrophysics Data System (ADS)

We have studied films of YBa2Cu3O7-? (YBCO) grown on SrTiO3 substrates, which were implanted with high doses of Co (1 × 1016-5 × 1017 ions/cm2 at 100 keV). The indirect modification of YBCO by local ion implantation of Co into the substrate is investigated to evaluate the feasibility of a new planar technology for the fabrication of Josephson junctions. The modified YBCO might become a barrier region of a Josephson junction. We found a strong diffusion of the implanted Co ions out of the substrates into the YBCO films during the deposition process, forming YBa2Cu3-xCoxO7-?. Our EDX and SNMS analyses show that the Co concentration x is homogeneous across the films. YBa2Cu3-xCoxO7-? is well known to be an excellent barrier material for SNS-type Josephson junctions. Using a 1.4 ?m thick photoresist mask, we have locally implanted Co into the substrates to study the lateral diffusion of Co into the YBCO film above the non-implanted region. We performed EDX analysis on cross-sectional TEM samples and found strong lateral diffusion of Co from the implanted substrate within the YBCO film located above the non-implanted region.

Kahlmann, F.; Weber, C.; Schubert, J.; Zander, W.; Buchal, Ch.; Kabius, B.; Breuer, U.

1997-02-01

425

Growth of YBa 2Cu 3O 7-? on Co implanted substrates  

NASA Astrophysics Data System (ADS)

We have studied films of YBa 2Cu 3O 7-? (YBCO) grown on SrTiO 3 substrates, which were implanted with high doses of Co (1 × 10 16-5 × 10 17 ions/cm 2 at 100 keV). The indirect modification of YBCO by local ion implantation of Co into the substrate is investigated to evaluate the feasibility of a new planar technology for the fabrication of Josephson junctions. The modified YBCO might become a barrier region of a Josephson junction. We found a strong diffusion of the implanted Co ions out of the substrates into the YBCO films during the deposition process, forming YBa 2Cu 3- xCo xO 7-?. Our EDX and SNMS analyses show that the Co concentration x is homogeneous across the films. YBa 2Cu 3- xCo xO 7-? is well known to be an excellent barrier material for SNS-type Josephson junctions. Using a 1.4 ?m thick photoresist mask, we have locally implanted Co into the substrates to study the lateral diffusion of Co into the YBCO film above the non-implanted region. We performed EDX analysis on cross-sectional TEM samples and found strong lateral diffusion of Co from the implanted substrate within the YBCO film located above the non-implanted region.

Weber, C.; Kahlmann, F.; Schubert, J.; Zander, W.; Kabius, B.; Breuer, U.; Buchal, Ch.

426

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

427

[Digital implant impression taking - an overview].  

PubMed

In dentist's daily practice, intraoral scanning systems are increased. Besides scanning of prepared teeth, also implants could be scanned intraorally. This clinical report describes the step-by-step techniques to scan digitally intraoral implants with two intraoral scanners (Lava™ C.O.S., 3M Espe and the CEREC AC connected with inLab MC XL, Sirona) for generating implant suprastructures without the use of impression materials, dental stone or implant impression copings. Different workflows, possibilities and limits by scanning dental implants are demonstrated. PMID:24585419

Mahl, Dominik; Glenz, Fabienne; Marinello, Carlo P

2014-01-01

428

Predicting Peri-implant Stresses Around Titanium and Zirconium Dental Implants-A Finite Element Analysis.  

PubMed

Due to anatomical and surgical constrains the implant placement may not be parallel to each other always. Non-parallel implants are subjected to detrimental stresses at implant bone interface. Also depending on type of implant material i.e. titanium or zirconium, stresses tend to vary due to change in physical and mechanical properties. Hence stress analysis at implant bone interface between different parallel and non-parallel implants becomes significant. Evaluation and comparison of stress distribution in the bone around two parallel and non-parallel titanium and zirconium dental implants on axial and non-axial loading supporting three unit fixed prosthesis. Three dimensional finite element models (M1, M2, M3) were made of three differently angulated implants in ANSYS (11.0 Version) software and P4 processor with a speed of 3 GHz and 3 Gb RAM hardware, common for titanium and zirconium implants. Stress around the implants was analyzed on an axial load of 200 N and a non-axial load of 50 N. In both titanium and zirconium implants on axial loading in cortical bone, higher stresses were observed in M3 followed by M2 and M1. On non-axial loading higher stresses were observed in M2, followed by M3 and M1. In both titanium and zirconium implants on axial and non-axial loading in cancellous bone stresses were higher in M3 followed by M2 and M1. Zirconium implants showed lower stresses in cortical bone and higher stresses in cancellous bone compared to titanium implants. Over all Stresses in the bone were more due to titanium implants than zirconium implants. Zirconium implants led to lower peri-implant stresses than titanium implants. PMID:24431734

Gujjarlapudi, Manmohan Choudary; Nunna, Narayana Venkata; Manne, Sanjay Dutt; Sarikonda, Varalakshmi Reddy; Madineni, Praveen Kumar; Meruva, Reddi Narasimha Rao

2013-09-01

429

Properties of 23Na implanted targets  

NASA Astrophysics Data System (ADS)

Ten types of 23Na implanted targets have been fabricated for the purposes of investigating the effects of proton beam bombardment on the implanted sodium distribution. Targets were implanted at energies of ENa = 10-30 keV using copper, tantalum, and nickel as host materials. Thin layers (100-200 Å) of chromium and gold were also evaporated over some of the targets to provide a protective layer for the implanted sodium. The 23Na( p, ?) resonance at a lab proton energy of Ep = 309 keV was used to determine the implanted distribution. Successive resonance profile measurements are presented for each implanted target, and the concurrent loss of 23Na resulting from beam bombardment is reported. The calculated temperature rise of the targets indicates that beam heating has a negligible effect on the implanted sodium distribution, and that the principal mechanism for 23Na loss during beam bombardment is sputtering.

Brown, T. A. D.; Deryckx, K.; García, A.; Sallaska, A. L.; Snover, K. A.; Storm, D. W.; Wrede, C.

2009-10-01

430

Early History and Challenges of Implantable Electronics  

PubMed Central

Implantable systems for biomedical research and clinical care are now a flourishing field of activities in academia as well as industrial institutions. The broad field includes experimental explorations in electronics, mechanical, chemical, and biological components and systems, and the combination of all these. Today virtually all implants involve both electronic circuits and micro-electro-mechanical-systems (MEMS). This article offers a very brief glance back at the early history of implant electronics in the period from the 1950s to the 1970s, by employing selected examples from the author’s research. This short review also discusses the challenges of implantable electronics at present, and suggests some potentially important trends in the future research and development of implantable microsystems. It is aimed as an introduction of implantable/attached electronic systems to research engineers that are interested in implantable systems as a section of Biomedical Instrumentations.

KO, WEN H.

2013-01-01

431

[Factors involved in endosseous implant function].  

PubMed

Periodontometric and Periotest mobility parameters of 87 endosseous implants were studied during a period of up to 6 years. Moreover, the condition of the surrounding bone and mucosa was assessed by means of the Periodontal Index (PI). Mobility of endosseous implants was lowest during the first year of insertion and highest at the end of the study. Among all those variables that had a favorable effect on implant function, the length of the implants was in the first line. What is called the osseointegration of dental implants is no longer evident after just a short period of masticatory loading by a denture. Mobility parameters of implants then increase to those of periodontally healthy natural teeth. Improved dental hygiene and cleansing of the periimplant area reduce the incidence of pathological findings and improve the prognosis of dental implants. PMID:1817937

Niedermeier, W; Küblbeck, K

1991-09-01

432

A wireless implantable sensor network system for in vivo monitoring of physiological signals.  

PubMed

A wireless implantable sensor network system (WISNS) is designed for in vivo monitoring physiological signals of a population of animals. WISNS can simultaneously monitor more than 15 animals, communicating three kinds of analog information among sensor nodes. Analog signals are transmitted to relay node at 800-KHz carrier by AM. Relay nodes digitalize and package them into messages, and then forward to the Wireless sensor network by Nordic RF technology (NWSN). Smaller overall dimensions (<2 cm (3)), lower power regulation, and dedicated packaging make the system suitable and compatible for implantable devices. The implantable sensor node, protocol stack of NWSN, and performance of the system are evaluated and optimized with ECG monitoring test of rats. Compared with those commercially available sensor nodes, our implantable one is leading in the weight and volume miniaturization, and our WISNS solution shows huge potential in achieving the compatibility of different animals. PMID:21536536

Fu, Xiuquan; Chen, Weihong; Ye, Shuming; Tu, Yuewen; Tang, Yawei; Li, Dingli; Chen, Hang; Jiang, Kai

2011-07-01

433

3DII implantation effect on corrosion properties of the AISI/SAE 1020 steel  

NASA Astrophysics Data System (ADS)

The three dimensional ion implantation technology (3DII) is one of the methods of improving the tribological characteristics and resistance to hydrogen embrittlement processes in metals. In this report, some results concerning the resistance effect of nitrogen ion implantation to oxidation of the sample, made of AISI/SAE 1020 steel, are given. The nitrogen ions were implanted in the discharge chamber of the JUPITER reactor. Both the treated and untreated samples were tested through potential-static measurements, which permitted to determine the corrosion current, the slopes that characterise the braking level of anode and cathode reactions. The polarization resistance near the corrosion potential is calculated. The results of the study encourage to consider the nitrogen ion implantation in high voltage and low pressure discharges as one of the methods of anticorrosive protection which do not change the geometric configuration of the treated steel pieces.

Dulcé M., Héctor J.; Rueda v., Alejandro; Dougar-Jabon, Valeri

2005-08-01

434

Rationale for tilted implants: FEA considerations and clinical reports  

PubMed Central

SUMMARY The prevalence of the elderly population, as well as life expectancy, increased in the final decades of the 20th century, as described in the World Health Organization 2004 Annual Report. The edentulous condition therefore has a negative impact on the oral health–related quality of life. Patients wearing complete dentures for many years infact, and especially in the mandible, are often unsatisfied because of the instability of the prosthesis during speaking and eating. To date dental implant treatment is well documented as a predictable treatment for partial or complete edentulism. On the other hand the rehabilitation of atrophied edentulous arches with endosseous implants (> 10 mm) in the posterior regions is often associated with anatomic problems such as bone resorption, poor bone quality, mandibular canal, and the presence of maxillary sinuses. Different procedures have been proposed to overcome these anatomic limitations. The use of tilted implants parallel to the anterior wall of the maxillary sinus or the mental foramen/inferior alveolar nerve has been proposed as a conservative solution for the treatment of the atrophic edentulous maxilla. Aim of this study was to describe, through a detailed literature review, the clinical and biomechanical rationale for tilting implants and to evaluate the long-term prognosis of immediately loaded full fixed prostheses for the treatment of edentulous patients (#35) with extreme bone atrophy rehabilited with both axial (#70) and tilted (#70) implants from 2008 to 2010. The results of the present study would suggest that this new surgical technique may reduce patient morbidity and extend the indications for immediate loading full fixed rehabilitations. This improves the predictability of treatment goal, allows for a better risk management, and provides more individual information for the patient. These are the most important aspects of this technology, which may contribute to establish higher-quality standards in implantology.

DE VICO, G.; BONINO, M.; SPINELLI, D.; SCHIAVETTI, R.; SANNINO, G.; POZZI, A.; OTTRIA, L.

2011-01-01

435

Rationale for tilted implants: FEA considerations and clinical reports.  

PubMed

The prevalence of the elderly population, as well as life expectancy, increased in the final decades of the 20th century, as described in the World Health Organization 2004 Annual Report. The edentulous condition therefore has a negative impact on the oral health-related quality of life. Patients wearing complete dentures for many years infact, and especially in the mandible, are often unsatisfied because of the instability of the prosthesis during speaking and eating. To date dental implant treatment is well documented as a predictable treatment for partial or complete edentulism. On the other hand the rehabilitation of atrophied edentulous arches with endosseous implants (> 10 mm) in the posterior regions is often associated with anatomic problems such as bone resorption, poor bone quality, mandibular canal, and the presence of maxillary sinuses. Different procedures have been proposed to overcome these anatomic limitations. The use of tilted implants parallel to the anterior wall of the maxillary sinus or the mental foramen/inferior alveolar nerve has been proposed as a conservative solution for the treatment of the atrophic edentulous maxilla. Aim of this study was to describe, through a detailed literature review, the clinical and biomechanical rationale for tilting implants and to evaluate the long-term prognosis of immediately loaded full fixed prostheses for the treatment of edentulous patients (#35) with extreme bone atrophy rehabilited with both axial (#70) and tilted (#70) implants from 2008 to 2010. The results of the present study would suggest that this new surgical technique may reduce patient morbidity and extend the indications for immediate loading full fixed rehabilitations. This improves the predictability of treatment goal, allows for a better risk management, and provides more individual information for the patient. These are the most important aspects of this technology, which may contribute to establish higher-quality standards in implantology. PMID:23277870

DE Vico, G; Bonino, M; Spinelli, D; Schiavetti, R; Sannino, G; Pozzi, A; Ottria, L

2011-07-01

436

Wearable and Implantable Sensors: The Patient's Perspective  

PubMed Central

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.

Bergmann, Jeroen H. M.; Chandaria, Vikesh; McGregor, Alison

2012-01-01

437