157 research outputs found
Temperature stabilized linkage
A temperature compensated passive linkage for interconnecting two members having different coefficients of expansion. Preferably the linkage is utilized for interconnecting the stabilizer of a plane with its elevator. The stabilizer may be a graphite epoxy composite while the elevator may consist of aluminum-fiberglass. The differences in the rate of expansion of the two members is compensated by the linkage of the invention which in turn will move a side load hinge fitting to minimize aerodynamic and mechanical problems
QUANTITATIVE ANALYSIS ON THE MUSCULAR ACTIVITY OF LOWER EXTREMITY DURING WATER WALKING
This study compared water walking (WW) with land walking (LW) in order to evaluate the muscular activities of the lower extremity. Nine young healthy subjects performed WW at voluntary slow, normal and fast speeds for 8 seconds with two repetitions. On the LW condition, subjects performed two trials at normal pace. Surface electromyography electrodes were placed on the tibialis anterior (TA), medial gastrocnemius (GAS), rectus femoris (RF) and biceps femoris (BF). As for WW, each muscular activity patterns at different speeds had moderate or high correlation with LW in cross correlation function (r = 0.53-0.90). The mean value of the muscular activity of GAS at slow speed condition during WW were lower than that of LW. At the fast speed condition, TA, RF and BF activities in WW were higher than that of LW. It was considered that WW was able to simulate LW at any levels of speeds and stimulate thigh muscles and TA sufficiently even in slow speed WW
Effects of broadening and electron overheating in tunnel structures based on metallic clusters
We study the influence of energy levels broadening and electron subsystem
overheating in island electrode (cluster) on current-voltage characteristics of
three-electrode structure. A calculation scheme for broadening effect in
one-dimensional case is suggested. Estimation of broadening is performed for
electron levels in disc-like and spherical gold clusters. Within the
two-temperature model of metallic cluster and by using a size dependence of the
Debye frequency the effective electron temperature as a function of bias
voltage is found approximately. We suggest that the effects of broadening and
electron overheating are responsible for the strong smoothing of
current-voltage curves, which is observed experimentally at low temperatures in
structures based on clusters consisting of accountable number of atoms.Comment: 8 pages, 5 figure
Microscopic theory of single-electron tunneling through molecular-assembled metallic nanoparticles
We present a microscopic theory of single-electron tunneling through metallic
nanoparticles connected to the electrodes through molecular bridges. It
combines the theory of electron transport through molecular junctions with the
description of the charging dynamics on the nanoparticles. We apply the theory
to study single-electron tunneling through a gold nanoparticle connected to the
gold electrodes through two representative benzene-based molecules. We
calculate the background charge on the nanoparticle induced by the charge
transfer between the nanoparticle and linker molecules, the capacitance and
resistance of molecular junction using a first-principles based Non-Equilibrium
Green's Function theory. We demonstrate the variety of transport
characteristics that can be achieved through ``engineering'' of the
metal-molecule interaction.Comment: To appear in Phys. Rev.
Pressure tuning of structure, superconductivity and novel magnetic order in the Ce-underdoped electron-doped cuprate T'-Pr_1.3-xLa_0.7Ce_xCuO_4 (x = 0.1)
High-pressure neutron powder diffraction, muon-spin rotation and
magnetization studies of the structural, magnetic and the superconducting
properties of the Ce-underdoped superconducting (SC) electron-doped cuprate
system T'-Pr_1.3-xLa_0.7Ce_xCuO_4 with x = 0.1 are reported. A strong reduction
of the lattice constants a and c is observed under pressure. However, no
indication of any pressure induced phase transition from T' to T structure is
observed up to the maximum applied pressure of p = 11 GPa. Large and non-linear
increase of the short-range magnetic order temperature T_so in
T'-Pr_1.3-xLa_0.7Ce_xCuO_4 (x = 0.1) was observed under pressure.
Simultaneously pressure causes a non-linear decrease of the SC transition
temperature T_c. All these experiments establish the short-range magnetic order
as an intrinsic and a new competing phase in SC T'-Pr_1.2La_0.7Ce_0.1CuO_4. The
observed pressure effects may be interpreted in terms of the improved nesting
conditions through the reduction of the in-plane and out-of-plane lattice
constants upon hydrostatic pressure.Comment: 11 pages, 10 figure
Detection of siRNA administered to cells and animals by using a fluorescence intensity distribution analysis polarization system
Small interfering RNA (siRNA) has excellent pharmacological features and is expected to be used for therapeutic drug development. To this end, however, new RNA technology needs to be established so that extremely small amounts (less than 1 pmol) of siRNA can be detected in organs of experimental animals and in human blood to facilitate pharmacokinetics studies. An important feature is that this new technology is not dependent on radioisotopes and can detect siRNA molecules identical to those used for drug development in preclinical tests with experimental animals or in clinical tests with humans. We report a convenient method that can detect small amounts of siRNA. The method uses high-power confocal microscopic analysis of fluorescence polarization in DNA probes that are bound to one of the strands of siRNA and directly quantitates the copy number of siRNA molecule after extraction from specimens. A pharmacokinetic study to examine the blood retention time of siRNA/cationic liposomes in mice showed that this straightforward method is consistent with the other reverse transcriptase polymerase chain reaction amplification-based method. We believe that the entire process is simple and applicable for a high-throughput analysis, which provides excellent technical support for fundamental research on RNA interference and development of siRNA drugs
Oxygen on-site Coulomb energy in PrLaCeCuO and BiSrCaCuO and its relation with Heisenberg exchange
We study the electronic structure of electron-doped
PrLaCeCuO (PLCCO ; = 27 K, x = 0.1) and
hole-doped BiSrCaCuO (Bi2212 ; = 90 K) cuprate
superconductors using x-ray absorption spectroscopy (XAS) and resonant
photoemission spectroscopy (Res-PES). From Res-PES across the O K-edge and Cu
L-edge, we identify the O 2p and Cu 3d partial density of states (PDOS) and
their correlation satellites which originate in two-hole Auger final states.
Using the Cini-Sawatzky method, analysis of the experimental O 2p PDOS shows an
oxygen on-site Coulomb energy for PLCCO to be = 3.30.5 eV and for
Bi2212, = 5.60.5 eV, while the copper on-site Coulomb correlation
energy, = 6.50.5 eV for Bi2212. The expression for the Heisenberg
exchange interaction in terms of the electronic parameters ,
, charge-transfer energy and Cu-O hopping obtained
from a simple CuO cluster model is used to carry out an optimization
analysis consistent with known from scattering experiments. The analysis
also provides the effective one band on-site Coulomb correlation energy
and the effective hopping . PLCCO and Bi2212 are shown
to exhibit very similar values of / 9-10,
confirming the strongly correlated nature of the singlet ground state in the
effective one-band model for both the materials.Comment: 13, pages, 11 figure
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