Search results for "TUNNEL"
showing 10 items of 576 documents
Evaluation of carpal tunnel syndrome in patients with polyneuropathy
1997
The difference between the median nerve latency to the second lumbrical muscle and the ulnar nerve latency to the second interosseous muscle (L-I DIFF) was tested in a prospective study to discriminate whether prolonged distal motor latency of the median nerve in patients with polyneuropathy (PNP) reflects an additional carpal tunnel syndrome (CTS). We investigated 92 patients (107 hands) with CTS, 30 patients (34 hands) with PNP, 22 patients (27 hands) with CTS and coexisting PNP (PNP+CTS), and 77 controls (87 hands). L-I DIFF was significantly prolonged in both the CTS and PNP+CTS patients as compared to PNP patients and controls. It proved to be the most specific test to differentiate be…
Direct and Indirect Effects of Function in Associated Variables Such as Depression and Severity on Pain Intensity in Women with Carpal Tunnel Syndrome
2015
Objective To determine the direct and indirect effects of function on clinical variables such as age, pain intensity, years of the disease, severity of symptoms, and depression in women with electrodiagnostic and clinical diagnosis of carpal tunnel syndrome (CTS). Design A cross-sectional study. Setting Patients from an urban hospital referred to a university clinic. Methods Two hundred and forty-four (n = 224) women with CTS were included. Demographic and clinical data, duration of symptoms, function, symptom's severity of the symptoms, pain intensity, and depression were self-reported collected. Correlation and path analysis with maximum likelihood estimation were conducted to assess the …
Aerodynamics of Ski Jumping
2016
Ski jumping is an exciting and primarily competitive sport involving both ballistic and aerodynamic factors. The ballistic factors are release velocity and release position of a ski jumper from the take-off table, whereas aerodynamic factors include the gliding properties of the jumper/ski system (velocity, suit design, surface area, posture of the jumper/ski system, resisting and lifting forces). Both ballistic and aerodynamic factors place special demands on the jumper so that he/she can, for example, optimally maximize the vertical lift and minimize the drag forces. Ski jumping has attracted spectators 200 years and it has undergone several notable steps in the development of performance…
Supersymmetric structures for second order differential operators
2012
Necessary and sufficient conditions are obtained for a real semiclassical partial differential operator of order two to possess a supersymmetric structure. For the operator coming from a chain of oscillators, coupled to two heat baths, we show the non-existence of a smooth supersymmetric structure, for a suitable interaction potential, provided that the temperatures of the baths are different.
Properties of native ultrathin aluminium oxide tunnel barriers
2003
We have investigated planar metal–insulator–metal tunnel junctions with aluminium oxide as the dielectricum. These oxide barriers were grown on an aluminium electrode in pure oxygen at room temperature till saturation. By applying the Simmons model we derived discrete widths of the tunnelling barrier, separated by Δs ≈ 0.38 nm. This corresponds to the addition of single layers of oxygen atoms. The minimum thickness of s0 ≈ 0.54 nm is then due to a double layer of oxygen. We found a strong and systematic dependence of the barrier height on the barrier thickness. Breakdown fields up to 5 GV m−1 were reached. They decreased strongly with increasing barrier thickness. Electrical breakdown could…
Excess Electrons at Oxide Surfaces
2015
Excess electrons profoundly affect the properties of oxide surfaces. The present review deals with excess charges on rutile and anatase. These much studied titania polymorphs open with strong prospects regarding (photo)catalysis and dye-sensitized solar cells. In the complex landscape of the mechanisms of electron trapping and electron transfer toward adsorbates, excess electrons open with flexible model systems which are the focus of an extensive research effort.
Lateral Fusion of Chemical Vapor Deposited N = 5 Armchair Graphene Nanoribbons
2017
Bottom-up synthesis of low-bandgap graphene nanoribbons with various widths is of great importance for their applications in electronic and optoelectronic devices. Here we demonstrate a synthesis of N = 5 armchair graphene nanoribbons (5-AGNRs) and their lateral fusion into wider AGNRs, by a chemical vapor deposition method. The efficient formation of 10- and 15- AGNRs is revealed by a combination of different spectroscopic methods, including Raman and UV−visnear-infrared spectroscopy as well as by scanning tunneling microscopy. The degree of fusion and thus the optical and electronic properties of the resulting GNRs can be controlled by the annealing temperature, providing GNR films with o…
Comparison between probe stagnation point heat flux measurements and correlation formulas in SCIROCCO plasma wind tunnel tests
2012
A large part of the SCIROCCO Arc Heater Performance Map has been investigated. The heat flux measurements at the stagnation point of t he facility Calibratio Probe have been used to find an experimental fit. Such a formula ha s been compared with the predictions of the De Filippis-Serpico equation and the well known Fay-Riddell formula. Finally the experimental fit has been also compared with the Sa gner-Verant formula obtained at the ONERA F4 hypersonic plasma wind tunnel.
Dynamics of spin state conversion processes in the solid state
1989
High spin (HS) ⇌ low spin (LS) conversions in transition metal complexes are nonradiative transitions between spin states. In this contribution, we present a study of the temperature and pressure dependence of the HS ⇌ LS intersystem crossing dynamics. For some iron(II) spin-crossover complexes, the rate constants were determined by line shape analysis of57Fe Mossbauer spectra. Their temperature dependence is described by an Arrhenius equation, their pressure dependence is interpreted within absolute rate theory. HS → LS conversion rates at low temperatures were determined from the relaxation of light-induced formation of HS states, monitored by optical spectroscopy. Deviations from a simpl…
Intersystem crossing in Fe(II) coordination compounds
1994
Fe(II) spin-crossover systems can be quantitatively converted from the low-spin (LS) to the high-spin (HS) state well below the thermal transition temperature by irradiating either into the metal-ligand charge transfer or d-d absorption bands, and even in low-spin systems a transient population of the HS state can be achieved. This fact can be made use of to determine HS → LS relaxation rate constants for a wide variety of Fe(II) spin-crossover and low-spin systems. The HS → LS relaxation shows strong deviations from an Arrhenius behaviour, with nearly temperature-independent tunnelling below ∼70 K and a thermally activated process above ∼100 K. The range of more than 12 orders of magnitude…