Novel Device (novel + device)

Distribution by Scientific Domains


Selected Abstracts


Figulla ASD Occluder versus Amplatzer Septal Occluder: A Comparative Study on Validation of a Novel Device for Percutaneous Closure of Atrial Septal Defects

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2009
AYSENUR PAC M.D.
Objectives: Occlutech Figulla ASD Occluder (FSO) is an alternative device to Amplatzer Septal Occluder (ASO) with some structural innovations including increased flexibility, minimizing the amount of material implanted, and absence of the left atrial clamp. We aimed to report our experiences with FSO and compare the outcomes of this novel device versus ASO. Interventions: Between December 2005 and February 2009, 75 patients diagnosed with secundum atrial septal defects underwent transcatheter closure. The FSO device was used in 33 patients, and the ASO was used in 42. Results: Patient characteristics, stretch size of the defect, device left disc size, procedure, and fluoroscopy time were similar between the groups. However, the difference between device waist size and stretched diameter of the defect was significantly higher, and device delivery sheath was significantly larger in FSO group and device left disc size was significantly lower in the FSO group. In all subjects, the residual shunt was small to trivial during follow-up and the reduction in prevalence of residual shunt with time was similar in both groups (P = 0.68). We found no differences in complication rate between the two devices; however, device embolization to the pulmonary bifurcation in one patient was recorded as major complication in FSO device group. Conclusions: Both devices are clinically safe and effective in ASD closure. FSO device has similar outcomes when compared to ASO device. Difficulties in selecting the correct device size in larger defects and larger venous sheath requirement need to be evaluated in further studies. [source]


A Novel Device for Single Particle Light Scattering Size Analysis and Concentration Measurement at High Pressures and Temperatures

PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 2 2008
Heinz Umhauer
Abstract Based on the findings of previous work, a novel instrument was developed for the size analysis and concentration measurement of particles dispersed in gases at high temperatures (600,°C) and pressures (16 bar). The main motivation for the construction of this device was a measurement requirement at the conditions of a pressurized pulverized coal combustion (PPCC) test installation in Dorsten, Germany. The development of a high efficiency (>,50,%), coal based, combined cycle process, and specifically, the development of efficient gas cleaning technology for gas combustion under demanding conditions (1400,°C and 16 bar) was the main target. A suitable measurement technique was required for the determination of particle size and concentration downstream of the gas cleaning equipment, which is able to operate close to the given conditions. The performance of the novel device was tested in several measurement series with various monodisperse aerosols at ambient conditions as well as in high pressure, high temperature situations with very satisfactory results, i.e., the lower detection limit (50,% counting efficiency at ca. 0.3 ,m) and resolution of the novel device are comparable to state of the art instruments (of the same principle) intended for room temperature operation. [source]


SDS-CGE of proteins in microchannels made of SU-8 films

ELECTROPHORESIS, Issue 18 2006
Maria Agirregabiria
Abstract This work describes the SDS-CGE of proteins carried out in microchannels made of the negative photoresist EPON SU-8. Embedded electrophoretic microchannels have been fabricated with a multilayer technology based on bonding and releasing steps of stacked SU-8 films. This technology allows the monolithic integration of the electrodes in the device. A high wafer fabrication yield and mass production compatibility guarantees low costs and high reliability. A poly(methyl methacrylate) (PMMA) packaging allows an easy setup and replacement of the device for electrophoresis experiments. In addition, the wire-bonding step is avoided. The electrophoretic mobilities of four proteins have been measured in microchannels filled with polyacrylamide. Different pore sizes have been tested obtaining their Ferguson plots. Finally, a separation of two proteins (20 and 36,kDa) has been carried out confirming that this novel device is suitable for protein separation. A resolution of 2.75 is obtained. This is the first time that this SU-8 microfluidic technology has been validated for SDS-CGE of proteins. This technology offers better separation performance than glass channels, at lower costs and with an easy packaging procedure. [source]


The Aqualon SLT: A novel device for measuring hair stiffness and lubricity

INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2010
K. A. Vaynberg
J. Cosmet. Sci., 60, 135,141 (March/April 2009) Synopsis The ability to quantify hair property changes in response to treatment is essential to the successful development of new formulations and benefiting agents. In the attempt to expand the toolbox of hair tress testing tools, we developed a device that allows hair scientists to measure hair tress changes in stiffness and lubricity. The tool is based on a system of pins mounted on free rotating bearings and is operated in two modes: rotating and stationary. The hair attributes are measured by threading a hair tress through the pin assembly and measuring the total work of pulling through in rotational and stationary modes (the latter mode is obtained by immobilizing pins by a retaining plate). The data thus obtained is de-convoluted into the work of apparent stiffness (rotational mode) and the work of the friction-on-pins or lubricity (stationary mode minus the apparent stiffness). The data can be further reduced to produce an apparent friction coefficient defined as a ratio of the apparent lubricity to the apparent stiffness. This work demonstrates the utility of the parameters measured by the Aqualon SLT and illustrates how the device can be used to predict and understand the impacts of various hair treatments. [source]


Figulla ASD Occluder versus Amplatzer Septal Occluder: A Comparative Study on Validation of a Novel Device for Percutaneous Closure of Atrial Septal Defects

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2009
AYSENUR PAC M.D.
Objectives: Occlutech Figulla ASD Occluder (FSO) is an alternative device to Amplatzer Septal Occluder (ASO) with some structural innovations including increased flexibility, minimizing the amount of material implanted, and absence of the left atrial clamp. We aimed to report our experiences with FSO and compare the outcomes of this novel device versus ASO. Interventions: Between December 2005 and February 2009, 75 patients diagnosed with secundum atrial septal defects underwent transcatheter closure. The FSO device was used in 33 patients, and the ASO was used in 42. Results: Patient characteristics, stretch size of the defect, device left disc size, procedure, and fluoroscopy time were similar between the groups. However, the difference between device waist size and stretched diameter of the defect was significantly higher, and device delivery sheath was significantly larger in FSO group and device left disc size was significantly lower in the FSO group. In all subjects, the residual shunt was small to trivial during follow-up and the reduction in prevalence of residual shunt with time was similar in both groups (P = 0.68). We found no differences in complication rate between the two devices; however, device embolization to the pulmonary bifurcation in one patient was recorded as major complication in FSO device group. Conclusions: Both devices are clinically safe and effective in ASD closure. FSO device has similar outcomes when compared to ASO device. Difficulties in selecting the correct device size in larger defects and larger venous sheath requirement need to be evaluated in further studies. [source]


A non-invasive method for studying an index of pupil diameter and visual performance in the rhesus monkey

JOURNAL OF MEDICAL PRIMATOLOGY, Issue 2 2006
Sarah J. Fairhall
Abstract Background, A non-invasive model has been developed to estimate gaze direction and relative pupil diameter, in minimally restrained rhesus monkeys, to investigate the effects of low doses of ocularly administered cholinergic compounds on visual performance. Methods, Animals were trained to co-operate with a novel device, which enabled eye movements to be recorded using modified human eye-tracking equipment, and to perform a task which determined visual threshold contrast. Responses were made by gaze transfer under twilight conditions. 4% w/v pilocarpine nitrate was studied to demonstrate the suitability of the model. Results, Pilocarpine induced marked miosis for >3 h which was accompanied by a decrement in task performance. Conclusions, The method obviates the need for invasive surgery and, as the position of point of gaze can be approximately defined, the approach may have utility in other areas of research involving non-human primates. [source]


Effect of cyclic mechanical loading on osteoclast recruitment in periodontal tissue

JOURNAL OF PERIODONTAL RESEARCH, Issue 1 2010
K. Nozaki
Nozaki K, Kaku M, Yamashita Y, Yamauchi M, Miura H. Effect of cyclic mechanical loading on osteoclast recruitment in periodontal tissue. J Periodont Res 2009; doi: 10.1111/j.1600-0765.2008.01193.x. © 2009 The Authors. Journal compilation © 2009 Blackwell Munksgaard Background and Objective:, It is well accepted that cyclic mechanical loading induces osteoclastogenesis in periodontal tissue, but its molecular mechanisms are not well understood, in part because of a lack of appropriate models. In this study, we investigated a novel device that allows cyclic mechanical loading to be performed in a well-controlled manner. Furthermore, by employing this model, the effect of cyclic loading on osteoclast recruitment in the periodontal tissue was described. Material and Methods:, By using a newly developed device, the cyclic loading of 20 n (reference loading corresponding to the fracture hardness of dietary pellets) and two excessive loadings (i.e. 30 and 40 n) were applied to maxillary right molars in rats for up to 7 d, and osteoclast recruitment in the periodontal tissue was evaluated by analyzing relevant marker proteins using immunohistochemistry. Results:, Osteoclastogenesis was induced by day 3 within alveolar bone subjected to a compression force of 30 n. With both 30 and 40 n loadings, cells that were positive to for tartrate-resistant acid phosphate, receptor activator of nuclear factor-,B ligand and osteoprotegerin were significantly increased in the alveolar bone/periodontal ligament in a time-dependent manner. Conclusion:, A new device was developed that allows various levels of cyclic mechanical loading to be exerted. By using this device in rats, early events of osteoclast recruitment in the periodontal tissues were observed with excessive loadings in a time-dependent manner, indicating the usefulness of this model. [source]


Thoracoscopic cell sheet transplantation with a novel device

JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 4 2009
Masanori Maeda
Abstract Regenerative medicine with transplantable cell sheets fabricated on temperature-responsive culture surfaces has been successfully achieved in clinical applications, including skin and cornea treatment. Previously, we reported that transplantation of fibroblast cell sheets to wounded lung had big advantages for sealing intraoperative air leaks compared with conventional materials. Here, we report a novel device for minimally invasive transplantation of cell sheets in endoscopic surgery, such as video-assisted thoracoscopic surgery (VATS). The novel device was designed with a computer-aided design (CAD) system, and the three-dimensional (3D) data were transferred to a 3D printer. With this rapid prototyping system, the cell sheet transplantation device was fabricated using a commercially available photopolymer approved for clinical use. Square cell sheets (24 × 24 mm) were successfully transplanted onto wound sites of porcine lung placed in a human body model, with the device inserted through a 12 mm port. Such a device would enable less invasive transplantation of cell sheets onto a wide variety of internal organs. Copyright © 2009 John Wiley & Sons, Ltd. [source]


A novel visual analogue scale (VAS) device: an instrument based on the VAS designed to quantify the subjective visual experience

OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2004
Jonathan S. Pointer
Abstract Purpose :,To evaluate a novel device intended to facilitate the direct quantification of the subjective visual experience. The design principle is based on that of the visual analogue scale (VAS) technique but obviates the need for subsequent measurement unlike the administration of the conventional paper VAS. Methods :,The visual experience of 134 normally sighted 17,40-year-olds was quantified using (in randomised sequence) a paper VAS and the novel VAS device. A notional 100-point scale was utilised in either case, and the extreme descriptive anchors for both instruments were ,dreadful' and ,perfect'. Results :,The degree of clinical agreement between the two alternative VAS techniques was very high. A small bias (mean = +0.7 VAS units: 95% confidence interval 0.3,1.2 units) towards the paper VAS was evident in these data, an outcome of no clinical significance or impediment as regards the substitution of the novel device for the conventional paper-based approach. Conclusions :,The moving of a bead along a wire is shown to be a clinically and statistically reliable alternative procedure to the pen-marking of a conventional paper VAS for the evaluation of the recent subjective visual experience, provided that the same minimum/maximum descriptive anchors are used for either instrument. The instant quantification of the VAS score afforded by the novel technique introduced here broadens the potential clinical application of this technique. [source]


A Novel Device for Single Particle Light Scattering Size Analysis and Concentration Measurement at High Pressures and Temperatures

PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 2 2008
Heinz Umhauer
Abstract Based on the findings of previous work, a novel instrument was developed for the size analysis and concentration measurement of particles dispersed in gases at high temperatures (600,°C) and pressures (16 bar). The main motivation for the construction of this device was a measurement requirement at the conditions of a pressurized pulverized coal combustion (PPCC) test installation in Dorsten, Germany. The development of a high efficiency (>,50,%), coal based, combined cycle process, and specifically, the development of efficient gas cleaning technology for gas combustion under demanding conditions (1400,°C and 16 bar) was the main target. A suitable measurement technique was required for the determination of particle size and concentration downstream of the gas cleaning equipment, which is able to operate close to the given conditions. The performance of the novel device was tested in several measurement series with various monodisperse aerosols at ambient conditions as well as in high pressure, high temperature situations with very satisfactory results, i.e., the lower detection limit (50,% counting efficiency at ca. 0.3 ,m) and resolution of the novel device are comparable to state of the art instruments (of the same principle) intended for room temperature operation. [source]


The PediSedate® device, a novel approach to pediatric sedation that provides distraction and inhaled nitrous oxide: clinical evaluation in a large case series

PEDIATRIC ANESTHESIA, Issue 2 2007
WILLIAM T. DENMAN MD FRCA
Summary Background:, Pediatric sedation is of paramount importance but can be challenging. Fear and anticipatory anxiety before invasive procedures often lead to uncooperativeness. A novel device (PediSedate®) provides sedation through a combination of inhaled nitrous oxide and distraction (video game). We evaluated the acceptability and safety of the PediSedate® device in children. Methods:, We enrolled children between 3 and 9 years old who were scheduled to undergo surgical procedures that required general inhalational anesthesia. After the device was applied, he/she played a video game while listening to the audio portion of the game through the earphones. Nitrous oxide in oxygen was administered via the nasal piece of the headset starting at 50% and increasing to 70%, in 10% increments every 8 min. Treatment failures, vital signs, arterial oxygen saturation, depth of sedation, airway patency, side effects, acceptance of the device and parental satisfaction were all evaluated. Results:, Of 100 children included, treatment failure occurred in 18% mainly because of poor tolerance of the device. At least 96% of the children who completed the study exhibited an excellent degree of sedation, 22% had side effects, and none experienced serious airway obstruction. Nausea and vomiting were the most common side effects and no patients had hemodynamic instability. Conclusions:, The PediSedate® device combines nonpharmacologic with pharmacologic methods of sedation. Most of the children we evaluated were able to tolerate the PediSedate® device and achieved an adequate degree of sedation. [source]


Quantum and conversion efficiency calculation of AlGaAs/GaAs multiple quantum well solar cells

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 9 2005
J. C. Rimada
Abstract The quantum well solar cell (QWSC) is a novel device that has been proposed by Barnham and co-workers at Imperial College London. In this work, the quantum efficiency for AlGaAs/GaAs QWSC has been calculated and compared with available data from the group at Imperial College London. Quantum efficiency calculations will be presented and compared with experimental data for several AlGaAs/GaAs QWSC, obtaining good agreement. The photocurrent then is calculated from the quantum efficiency calculations and included in the J(V) relation to optimize the efficiency of AlGaAs/GaAs QWSC. It also shows that for a range of quantum well widths and barrier bandgaps the conversion efficiencies of the quantum well solar cell are higher than the corresponding homogeneous p,i,n solar cell. Our results give a broad representation of quantum well solar cell operation, and provide a profitable guide for designing and interpreting the performance characteristics of AlGaAs/GaAs QWSCs. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Estimating Subglottal Pressure via Airflow Redirection,

THE LARYNGOSCOPE, Issue 8 2007
Christopher D. Baggott
Abstract Subglottal pressure (SGP) is a valuable parameter in the research and clinical assessment of laryngeal function. The lungs serve as a constant pressure source during sustained phonation, and that pressure, SGP, can be used to determine the efficiency with which the larynx converts aerodynamic power to acoustic power. As the larynx serves as an aerodynamic transducer, the vocal efficiency (Ve) coefficient, defined as acoustic power (dB) divided by aerodynamic power (SGP × glottal airflow) has been shown to reliably reflect vocal health. However, current SGP measurement techniques are hesitantly used because of either an invasive nature or the requirement of intensive patient training. This study tests a novel device that has been designed to noninvasively estimate SGP through mechanical airflow redirection, producing a numeric output on completion of the trial, which lasts only a few seconds. The novelty of this design lies in the ease of use for both the patient and the clinician. Multiple mechanical airflow redirections occlude the airway for only 135 ms, which is predicted to limit the effect of confounding laryngeal reflexes that may occur during the trials. Additionally, the airflow redirection into a retention device allows for the pneumatic in-trial comparison of the estimated SGP with the pressure achieved by the patient, providing a numeric output to the clinician on completion. [source]


Improving diffraction by humidity control: a novel device compatible with X-ray beamlines

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 12 2009
Juan Sanchez-Weatherby
Dehydration of protein crystals is rarely used, despite being a post-crystallization method that is useful for the improvement of crystal diffraction properties, as it is difficult to reproduce and monitor. A novel device for hydration control of macromolecular crystals in a standard data-collection environment has been developed. The device delivers an air stream of precise relative humidity that can be used to alter the amount of water in macromolecular crystals. The device can be rapidly installed and is fully compatible with most standard synchrotron X-ray beamlines. Samples are mounted in cryoloops and the progress of dehydration can be monitored both optically and by the acquisition of diffraction images. Once the optimal hydration level has been obtained, cryocooling is easy to achieve by hand or by using a sample changer. The device has been thoroughly tested on several ESRF beamlines and is available to users. [source]


Computational Design and In Vitro Characterization of an Integrated Maglev Pump-Oxygenator

ARTIFICIAL ORGANS, Issue 10 2009
Juntao Zhang
Abstract For the need for respiratory support for patients with acute or chronic lung diseases to be addressed, a novel integrated maglev pump-oxygenator (IMPO) is being developed as a respiratory assist device. IMPO was conceptualized to combine a magnetically levitated pump/rotor with uniquely configured hollow fiber membranes to create an assembly-free, ultracompact system. IMPO is a self-contained blood pump and oxygenator assembly to enable rapid deployment for patients requiring respiratory support or circulatory support. In this study, computational fluid dynamics (CFD) and computer-aided design were conducted to design and optimize the hemodynamics, gas transfer, and hemocompatibility performances of this novel device. In parallel, in vitro experiments including hydrodynamic, gas transfer, and hemolysis measurements were conducted to evaluate the performance of IMPO. Computational results from CFD analysis were compared with experimental data collected from in vitro evaluation of the IMPO. The CFD simulation demonstrated a well-behaved and streamlined flow field in the main components of this device. The results of hydrodynamic performance, oxygen transfer, and hemolysis predicted by computational simulation, along with the in vitro experimental data, indicate that this pump-lung device can provide the total respiratory need of an adult with lung failure, with a low hemolysis rate at the targeted operating condition. These detailed CFD designs and analyses can provide valuable guidance for further optimization of this IMPO for long-term use. [source]


Functional and Biocompatibility Performances of an Integrated Maglev Pump-Oxygenator

ARTIFICIAL ORGANS, Issue 1 2009
Tao Zhang
Abstract To provide respiratory support for patients with lung failure, a novel compact integrated pump-oxygenator is being developed. The functional and biocompatibility performances of this device are presented. The pump-oxygenator is designed by combining a magnetically levitated pump/rotor with a uniquely configured hollow fiber membrane bundle to create an assembly free, ultracompact, all-in-one system. The hemodynamics, gas transfer and biocompatibility performances of this novel device were investigated both in vitro in a circulatory flow loop and in vivo in an ovine animal model. The in vitro results showed that the device was able to pump blood flow from 2 to 8 L/min against a wide range of pressures and to deliver an oxygen transfer rate more than 300 mL/min at a blood flow of 6 L/min. Blood damage tests demonstrated low hemolysis (normalized index of hemolysis [NIH],0.04) at a flow rate of 5 L/min against a 100-mm Hg afterload. The data from five animal experiments (4 h to 7 days) demonstrated that the device could bring the venous blood to near fully oxygen-saturated condition (98.6% ± 1.3%). The highest oxygen transfer rate reached 386 mL/min. The gas transfer performance was stable over the study duration for three 7-day animals. There was no indication of blood damage. The plasma free hemoglobin and platelet count were within the normal ranges. No gross thrombus is found on the explanted pump components and fiber surfaces. Both in vitro and in vivo results demonstrated that the newly developed pump-oxygenator can achieve sufficient blood flow and oxygen transfer with excellent biocompatibility. [source]


Protein loading, elution, and resolution behavior in a novel device that integrates ultrafiltration and chromatographic separation

BIOTECHNOLOGY & BIOENGINEERING, Issue 2 2003
Xiao-Ping Dai
Abstract Hollow fiber membranes and chromatographic resin beads are commonly employed in a variety of bioseparation processes. A new class of integrated separation devices is being studied in which the shell side of a hollow fiber device is filled with adsorbents/chromatographic resin beads. Such devices and the corresponding separation methods integrate feed broth clarification by the microfiltration/ultrafiltration membrane with bioproduct purification by the shell-side resin beads either as an adsorbent or as beads in elution chromatography. A mathematical model has been developed for the prediction of the chromatographic behavior of such an integrated device. Simulations have been done to study the effects of axial dispersion, feed flow rate, water permeation rate, fiber packing density, and void fraction. Numerical solutions were obtained by solving the governing equations. This model can reasonably describe the concentration profiles as well as the breakthrough and elution behaviors in the integrated device. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 83: 125,139, 2003. [source]


Infrared-monitored cold response in the assessment of Raynaud's phenomenon

CLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 1 2006
J. Foerster
Summary Background., Evaluation of treatments for Raynaud's phenomenon (RP) requires objective response parameters in addition to clinical activity scores. Thermographic monitoring of fingertip re-warming after cold challenge has been widely used but usually requires sophisticated equipment. We have previously shown that fingertip re-warming after cold challenge follows a first-order transient response curve that can be described by a single variable, designated ,. Objectives., Here, we describe a novel device termed a duosensor, which records the , value upon cold challenge in an automated manner. Methods., We determined , values in healthy probands, patients with primary or secondary RP associated with autoimmune disease and patients with scleroderma-associated RP following cold challenge, to determine assay variability, sensitivity and specificity. Results., Duosensor-based thermography exhibited low intraindividual variability in healthy probands. As expected, , values in RP patients were significantly increased compared with controls (8.08 ± 3.65 min vs. 3.23 ± 1.65 min). The duosensor-determined , value yielded a specificity of 94.6% and predictive value of 95.3% for the presence of RP in a retrospective analysis of 139 patients. Furthermore, in a cohort of scleroderma patients with RP, patient self-assessment of RP severity correlated with , values. Conclusions., Taken together, the present data suggest that , value determination provides a suitable outcome measure for clinical studies of novel RP treatments. As the duosensor is a simple stand-alone device requiring no supporting equipment and minimal personnel attention, it should allow RP activity monitoring even in clinical settings with minimal technical infrastructure. [source]


Synthesis and Assembly of Monodisperse High-Coercivity Silica-Capped FePt Nanomagnets of Tunable Size, Composition, and Thermal Stability from Microemulsions,

ADVANCED MATERIALS, Issue 19 2006
Q. Yan
A microemulsion approach to obtain high - coercivity (850 mT) FePt nanomagnets capped with a nanoscopic silica shell is reported (see figure). This versatile method allows the easy tuning of particle size and composition. The silica shell inhibits agglomeration and preserves the chemical stability of the particles up to 650,°C, and facilitates surface functionalization and particle assembly. These attributes are attractive for harnessing the nanomagnets for realizing novel devices and composites. [source]


Use of confocal and multiphoton microscopy for the evaluation of micro-optical components and emitters

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 4 2004
J.M. Girkin
Abstract We report on the application of confocal and multiphoton microscopic techniques for the evaluation of the latest generation of micro optical components. The optical emitting characteristics of arrays of matrix addressable GaN micrometer-sized light emitting diodes (micro-LEDs) have been measured using a commercial confocal microscope utilising the LEDs' own emission along with reflection confocal microscopy to determine the surface structure. Multiphoton induced luminescence from the 10,20-micron diameter emitters has also been used to examine the structure of the device and we compare this with electrically induced emission. In related work, the optical properties of micro lens arrays (10,100-micron diameter) fabricated in SiC, Sapphire, and Diamond have been determined using transmission confocal microscopy. Such optical microscopy techniques offer a simple, non-destructive method to determine the structure and performance of such novel devices. Microsc. Res. Tech. 64:293,296, 2004. © 2004 Wiley-Liss, Inc. [source]


Weak localization and the Mooij rule in disordered metals

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 2 2003
Mi-Ae Park
Abstract Weak localization leads to the same correction to both the conductivity and the McMillan's electron,phonon coupling constant , (and ,tr, transport electron,phonon coupling constant). Consequently the temperature dependence of the thermal electrical resistivity is decreasing as the conductivity is decreasing due to weak localization, which results in the decrease of the temperature coefficient of resistivity (TCR) with increasing the residual resistivity. When , and ,tr are approaching zero, only the residual resistivity part remains and it gives rise to the negative TCR. Accordingly, the Mooij rule is a manifestation of weak localization correction to the conductivity and the electron,phonon interaction. This understanding provides a new means of probing the phonon-mechanism in exotic superconductors and an opportunity of fabricating new novel devices. [source]


Collaborative Research Centre of the Deutsche Forschungsgemeinschaft Semiconductor Nanometer Devices Fundamentals , Concepts , Realisations

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 8 2004
Markus C. Amann
This Special Issue is a collection of Review Articles written by the members of the Collaborative Research Centre (SFB) 348 of the German Research Foundation (DFG). Its aims were the development of new methods for nanometer-scale structuring of semiconductors, the experimental and theoretical investigations of such nanostructures, and the design and prototyping of novel devices for high frequency, optical and optoelectronic applications. This required coordinated research efforts by physicists and electrical engineers into both basic physical phenomena and device oriented questions. [source]