768 research outputs found
Nuclear Wobbling Motion and Electromagnetic Transitions
The nuclear wobbling motion is studied from a microscopic viewpoint. It is
shown that the expressions not only of the excitation energy but also of the
electromagnetic transition rate in the microscopic RPA framework can be cast
into the corresponding forms of the macroscopic rotor model. Criteria to
identify the rotational band associated with the wobbling motion are given,
based on which examples of realistic calculations are investigated and some
theoretical predictions are presented.Comment: 39 pages, plain TeX, figures not included, available via conventional
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Development of Hydrologic Characterization Technology of Fault Zones
Through an extensive literature survey we find that there is very limited amount of work on fault zone hydrology, particularly in the field using borehole testing. The common elements of a fault include a core, and damage zones. The core usually acts as a barrier to the flow across it, whereas the damage zone controls the flow either parallel to the strike or dip of a fault. In most of cases the damage zone isthe one that is controlling the flow in the fault zone and the surroundings. The permeability of damage zone is in the range of two to three orders of magnitude higher than the protolith. The fault core can have permeability up to seven orders of magnitude lower than the damage zone. The fault types (normal, reverse, and strike-slip) by themselves do not appear to be a clear classifier of the hydrology of fault zones. However, there still remains a possibility that other additional geologic attributes and scaling relationships can be used to predict or bracket the range of hydrologic behavior of fault zones. AMT (Audio frequency Magneto Telluric) and seismic reflection techniques are often used to locate faults. Geochemical signatures and temperature distributions are often used to identify flow domains and/or directions. ALSM (Airborne Laser Swath Mapping) or LIDAR (Light Detection and Ranging) method may prove to be a powerful tool for identifying lineaments in place of the traditional photogrammetry. Nonetheless not much work has been done to characterize the hydrologic properties of faults by directly testing them using pump tests. There are some uncertainties involved in analyzing pressure transients of pump tests: both low permeability and high permeability faults exhibit similar pressure responses. A physically based conceptual and numerical model is presented for simulating fluid and heat flow and solute transport through fractured fault zones using a multiple-continuum medium approach. Data from the Horonobe URL site are analyzed to demonstrate the proposed approach and to examine the flow direction and magnitude on both sides of a suspected fault. We describe a strategy for effective characterization of fault zone hydrology. We recommend conducting a long term pump test followed by a long term buildup test. We do not recommend isolating the borehole into too many intervals. We do recommend ensuring durability and redundancy for long term monitoring
Structures of smooth muscle myosin and heavy meromyosin in the folded, shutdown state
Remodelling of the contractile apparatus within smooth muscle cells is an essential process that allows effective contractile activity over a wide range of cell lengths. The thick filaments may be redistributed via depolymerisation into inactive myosin monomers that have been detected in vitro, in which the long tail has a folded conformation. The structure of this folded molecule has been controversial. Using negative stain electron microscopy of individual folded molecules from turkey gizzard we show they are more compact than previously described, with heads and the three segments of the folded tail closely packed. Smooth muscle heavy meromyosin (HMM), which lacks two-thirds of the tail, closely resembles the equivalent parts of whole myosin. Image processing reveals a characteristic head region morphology for both HMM and myosin whose features are identifiable by comparison with less compact molecules. The two heads associate asymmetrically: the tip of one motor domain touches the base of the other, resembling the blocked and free heads of this HMM when it forms 2-D crystals on lipid. The tail of HMM lies between the heads, contacting the blocked motor domain, unlike in the 2-D crystal. The tail of the intact myosin is bent sharply and consistently at two positions close to residues 1175 and 1535. The first bend position correlates with a skip in the coiled coil sequence, the second does not. The first segment runs between the heads from the head-tail junction. Unexpectedly, the other segments associate only with the blocked head rather than both heads, such that the second bend lies at a specific position near the C-lobe of the blocked head regulatory light chain. Quantitative analysis of tail flexibility shows that the single coiled coil of HMM has an apparent Young’s modulus of about 0.5 GPa. The folded tail of the intact molecule is less flexible indicating interactions between the segments. The folded tail does not modify the compact head arrangement but stabilises it, indicating a structural mechanism for the very low ATPase activity of the folded molecule
Evaluation for Web-based Learning Material Utilizing Animation to Support Practicum Class for DTP
本研究は,ディジタルメディア表現能力を高めるために模倣学習を行うWeb動画教材の開発と評価・改善プロセスについて報告するものである.先行研究の学習モデルに基づき,実際にDTP実習を支援する学習環境を開発した.その評価プロセスから,学習者が一人で模倣学習を完遂するために,システム面で改善すべき機能が明らかとなった.それらの機能を実装した結果,学習者が一人で模倣学習を完遂できるレベルに教材の質を高めることができた.ただし,学習者の個人差に配慮するべきいくつかの課題は残された.ショートレタ
Spectral Properties of Quasiparticle Excitations Induced by Magnetic Moments in Superconductors
The consequences of localized, classical magnetic moments in superconductors
are explored and their effect on the spectral properties of the intragap bound
states is studied. Above a critical moment, a localized quasiparticle
excitation in an s-wave superconductor is spontaneously created near a magnetic
impurity, inducing a zero-temperature quantum transition. In this transition,
the spin quantum number of the ground state changes from zero to 1/2, while the
total charge remains the same. In contrast, the spin-unpolarized ground state
of a d-wave superconductor is found to be stable for any value of the magnetic
moment when the normal-state energy spectrum possesses particle-hole symmetry.
The effect of impurity scattering on the quasiparticle states is interpreted in
the spirit of relevant symmetries of the clean superconductor. The results
obtained by the non-self-consistent (T matrix) and the self-consistent
mean-field approximations are compared and qualitative agreement between the
two schemes is found in the regime where the coherence length is longer than
the Fermi length.Comment: to appear in Phys. Rev. B55, May 1st (1997
Local Electronic Structure of Defects in Superconductors
The electronic structure near defects (such as impurities) in superconductors
is explored using a new, fully self-consistent technique. This technique
exploits the short-range nature of the impurity potential and the induced
change in the superconducting order parameter to calculate features in the
electronic structure down to the atomic scale with unprecedented spectral
resolution. Magnetic and non-magnetic static impurity potentials are
considered, as well as local alterations in the pairing interaction. Extensions
to strong-coupling superconductors and superconductors with anisotropic order
parameters are formulated.Comment: RevTex source, 20 pages including 22 figures in text with eps
Associations Between Metal Levels in Whole Blood and IgE Concentrations in Pregnant Women Based on Data From the Japan Environment and Children’s Study
Background: Metal exposures could possibly affect allergic responses in pregnant women, although no studies have yet shown a clear relationship between the two, and such exposures might also affect the development of allergic diseases in children.
Methods: We investigated the relationship between metal concentrations in whole blood and immunoglobulin E (IgE; total and specific) in 14,408 pregnant women who participated in the Japan Environment and Children’s Study. The subjects submitted self-administered questionnaires, and blood samples were collected from them twice, specifically, during the first trimester and again during the second=third trimester. Concentrations of the metals Cd, Pb, Hg, Se, and Mn, as well as serum total and allergen-specific IgEs for egg white, house dust-mites (HDM), Japanese cedar pollen (JCP), animal dander, and moth, were measured. Allergen-specific IgE(s) were divided based on concentrations <0.35 or ≥0.35UA=mL, and the metal levels were divided into quartiles.
Results: Multivariable logistic regression analysis showed that there was a significant negative correlation between HDM- and animal dander-specific IgEs and Hg and Mn concentrations. Conversely, there was a significant positive relationship between JCP-specific IgE and Hg and Se concentrations.
Conclusions: Metal exposures may be related to both increases and decreases in allergen-specific IgEs in pregnant women.This work was supported by the Ministry of the Environment, Japan.Supplementary data related to this article can be found at https://doi.org/10.2188/jea.JE20180098
Scaling and optimisation of lateral super-junction multi-gate MOSFET for high drive current and low specific on-resistance in sub–50 V applications
The scaling of a non-planar super-junction (SJ) Si MOSFET based on SOI technology for low voltage rating applications (below 50 V) requires a subsequent optimisation of SJ unit. The scaling and the SJ optimisation are carried out with physically based commercial TCAD device simulations by Silvaco. The study is based on a meticulous calibration of drift-diffusion simulations against experimental characteristics of a 1 μm gate length SJ multi-gate MOSFET (SJ-MGFET) aiming at improving density, switching speed, drive current, breakdown voltage (BV), and specific on-resistance (Ron,sp). We investigate scaling of the device architecture to improve the device performance by optimising doping profile to achieve an avalanche-enabled device under a charge balanced condition. The optimised SJ-MGFETs scaled by a factor of 0.5 and 0.25, with a folded alternating U-shaped n/p-SJ drift region pillar of a width of 0.3 μm and a trench depth of 2.7 μm, achieve a low specific on-resistance (Ron,sp) of 7.68 mΩ⋅mm2 and 2.24 mΩ⋅mm2 (VGS = 10 V) and BV of 48 V and 26 V, respectively. The scaled 0.5 μm and 0.25 μm gate length SJ-MGFETs offer a transconductance (gm) of 20 mS/mm and 56 mS/mm at a drain voltage of 0.1 V, respectively, greatly improving the levels of integration in a CMOS architecture
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