Risk factors for silent cerebral infarcts in subcortical white matter and basal ganglia

BACKGROUND AND PURPOSE: The purpose of this study was to clarify whether the relevant risk factors for silent cerebral infarcts (SCIs) in subcortical white matter (WM) are different from those in the basal ganglia (BG). METHODS: Subjects of this study were 219 adults without a history of stroke or transient ischemic attack and without any abnormality on a neurological examination who consecutively visited the neurology service in our hospital between January 1994 and November 1997 requesting medical evaluation for possible cerebrovascular diseases. Subjects included 141 men and 78 women ranging in age from 33 to 83 years (mean+/-SD, 63.2+/-9.5 years). We performed brain MRIs and cervical/cranial MR angiographies on all subjects. In this study, SCI was defined as a focal lesion >5 mm in diameter that was prolonged on both T2-weighted and proton density images. RESULTS: SCIs in the WM and/or BG were detected in 88 (40.2%) of the 219 subjects. No SCI >15 mm was observed in this series. Fifty of the subjects had SCIs only in the WM, 32 subjects had SCIs in both the WM and BG, and 6 subjects had SCIs only in the BG. Thus, 82 (93.2%) of 88 subjects with SCIs had lesions in the WM. Most subjects with SCIs in the BG also had SCIs in the WM. Multiple logistic regression analyses revealed that age, female sex, and hypertension were significant and independent predictors of SCIs in the WM, and that age, a history of ischemic heart disease, and carotid artery stenosis were significant and independent predictors of SCIs in the BG. CONCLUSIONS: The present study indicated that the relevant risk factors for SCIs in the WM and those for SCI in the BG were different. Our results suggest that SCIs are prone to first appear in the WM in association with aging and hypertension, and the additional appearance of SCIs in the BG predicts a progression of generalized atherosclerosis that is manifested in the carotid and coronary arteries.     

Multi-component granulation in a fast fluidized bed

The granulation of multi-component particles was conducted in a fast fluidized bed with an atomizing binder solution. The effects of gas velocity and binder droplet diameter on granulation rate, granule size distribution and granule composition were studied. The granulation rate and granule yield were determined by the balance between the agglomeration rate of feed particles and the disintegration rate of granules because there was no secondary granulation. With the increase in gas velocity and the reduction in binder droplet size, the agglomeration rate of feed particles decreased but the disintegration rate of granules increased, resulting in a reduced granule yield. Despite the larger fraction of small particles in the granules, the homogenous granulation of multi-component particles was achieved.     

Optical properties of photoluminescent polycrystalline CuLa0.98Eu0.02O2 thin film prepared by pulsed laser deposition at room temperature

Smooth CuLa_0.98Eu_0.02O₂ thin film has successfully been prepared by pulsed laser deposition method at room temperature. Crystal structure of the obtained film was almost same as that of CuLa_0.98Eu_0.02O₂ polycrystalline ceramic. Orange luminescence with high intensity due to ⁵D₀ – ⁷F_0,1 transitions of Eu³⁺, which was an evidence of Eu³⁺ substitution for La³⁺ site in LaO₆ octahedra with the inversion symmetry, was also observed in the obtained film. The optical band gap of CuLa_0.98Eu_0.02O₂ was measured to be 2.85 eV from absorption spectroscopy.     

Investigation of VFT surges propagated into transformer and overvoltages applied to winding

Investigations were conducted on the VFT (Very Fast Transient) surges that propagate into a 500‐kV transformer. The disconnector restriking surge and ground fault surged were discussed. It was regarded that a large part of the surge voltage was applied just at the entrance of the transformer winding for the VFT surges. Thus, an equivalent circuit that models the windings was used for the analysis. The overvoltages that appear between the first winding sections at the entrance of the transformer were computed. The following was established. (1) The overvoltage between the first winding sections becomes greater when the magnitude of the voltage change at the transformer terminal is larger. The overvoltage between the first winding sections is not affected by the magnitude of the transformer terminal voltage. (2) For the disconnectors that are not connected directly to the transformer, the voltage change at the transformer terminal is not so large. (3) In the case of a ground fault at the GIS near the transformer, the voltage change at the transformer terminal is the same as that for a disconnector directly connected to the transformer. (4) In actual GIS, the disconnector that is connected directly to the transformer is not usually used. In this situation, the overvoltages that threaten the transformer insulation will not be generated by the restriking of the disconnectors. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(2): 20–26, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10225     

On a transient thermal stress problem in an infinite circular cylinder with a penny-shaped crack

In the present paper, we deal with finding the stress intensity factors under transient thermal loading in an infinitely long circular cylinder containing a penny-shaped crack. Variations of the stress intensity factors with time, which will be closely related with crack extension, are illustrated in the figures.     

Block-Orthogonal Frequency Division Multiplexing in Multi-Path Fading Channel

Orthogonal frequency division multiplexing (OFDM) is robust against multi-path interference due to using a lot of low symbol rate sub-carriers. In order to mitigate the degradation due to multi-path interference, guard time interval (GI) is inserted into each OFDM symbol. However, redundant allocation to GI leads to loss of effective transmission power. We propose the Block-OFDM which can reduce the GI overhead ratio per frame compared with conventional OFDM. In Block-OFDM system frequency domain equalization (FDE) is carried out in order to remove multi-path interference. We evaluated Block-OFDM performance in a frequency selective fading channel and compared with that of conventional OFDM. Ryohei Kimura received his B.E. and M.S degrees in communications engineering form Tohoku University, Sendai, Japan, in 2001 and 2003, respectively. In 2003, he joined Panasonic Mobile Communications Co., Ltd. His current research interests include such mobile communication technologies as OFDM and MIMO (MLD), and the like. Akiyoshi Monma received his B.E. in communications engineering form Tohoku University, Sendai, Japan, in 1998. In 1998, he joined Panasonic Mobile Communications Sendai R&D Lab. Co., Ltd. His current research interests include such mobile communication technologies as OFDM and PAPR reduction, and the like. Jinsong Duan received his B.E. and M.S. from Changsha Institute of Technology, China in 1987 and 1990. He received his Ph.D. from Osaka City University, Japan in 2000. From 2000–2003 he was with Mitsubishi Electric Corporation, where he engaged in research and development of WCDMA systems. From 2003, he joined Panasonic Mobile Communications Co., Ltd. His current interests include such mobile communication technologies as OFDM, MIMO, link adaptation, scheduling, and TDMA/FDMA/CDMA systems. Mitsuru Uesugi received his B.E. degree from Waseda University in 1986 and received his Ph.D degree from Tohoku University in 2004, respectively. He is a general manager in the Mobile Communication Technology Development Center of Panasonic Mobile Communications Co., Ltd. His current research interests include such mobile communication technologies as equalization, interference cancellation, modulation method, and the like.     

Good trellises for IC implementation of Viterbi decoders for linearblock codes

This paper investigates trellis structures of linear block codes for the integrated circuit (IC) implementation of Viterbi decoders capable of achieving high decoding speed while satisfying a constraint on the structural complexity of the trellis in terms of the maximum number of states at any particular depth. Only uniform sectionalizations of the code trellis diagram are considered. An upper-bound on the number of parallel and structurally identical (or isomorphic) subtrellises in a proper trellis for a code without exceeding the maximum state complexity of the minimal trellis of the code is first derived. Parallel structures of trellises with various section lengths for binary BCH and Reed-Muller (RM) codes of lengths 32 and 64 are analyzed. Next, the complexity of the IC implementation of a Viterbi decoder based on an L-section trellis diagram for a code is investigated. A structural property of a Viterbi decoder called add-compare-select (ACS)-connectivity which is related to state connectivity is introduced. This parameter affects the complexity of wire-routing (interconnections within the IC). The effect of five parameters namely: (1) effective computational complexity; (2) complexity of the ACS-circuit; (3) traceback complexity; (4) ACS-connectivity; and (5) branch complexity of a trellis diagram on the very large scale integration (VLSI) complexity of a Viterbi decoder is investigated. It is shown that an IC implementation of a Viterbi decoder based on a nonminimal trellis requires less area and is capable of operation at higher speed than one based on the minimal trellis when the commonly used ACS-array architecture is considered     

Lithium Ion Secondary Cell Prepared by a Printing Procedure,and Its Application to All-Solid-State Inorganic Lithium Ion Cells

We have developed a straightforward printing method for preparation of a lithium secondary cell. LiCo_1/3Ni_1/3Mn_1/3O₂ and Li₄Ti₅O₁₂ viscous printable pastes were used for the cathode and anode, respectively. Electrochemical measurement was used to characterize the capacitance of each cell, and field-emission scanning electron microscopy and particle size measurements were used to characterize particle size and morphology. These film electrodes functioned stably both in a standard liquid electrolyte and in an Li₂SiO₃ solid electrolyte, although the capacitance of the all-solid-state cell was significantly lower than that of the cell containing liquid electrolyte. When liquid electrolyte was used, the capacity decreased by 36% after 50 cycles. However, the capacity of 0.2 mA h/g remained almost the same even after 50 charge–discharge cycles, demonstrating the stability and strength of the all-solid-state lithium ion cell. It was also found that the cell resistance mostly arose from the electrode/electrolyte interface and not from the bulk electrolyte. Addition of a sol–gel to the solid electrolyte printable paste improved cell performance.     

A database of frequency distributions of energy depositions in small-size targets by electrons and ions

Linear energy transfer (LET) is an average quantity, which cannot display the stochastics of the interactions of radiation tracks in the target volume. For this reason, microdosimetry distributions have been defined to overcome the LET shortcomings. In this paper, model calculations of frequency distributions for energy depositions in nanometre size targets, diameters 1-100 nm, and for a 1 μm diameter wall-less TEPC, for electrons, protons, alpha particles and carbon ions are reported. Frequency distributions for energy depositions in small-size targets with dimensions similar to those of biological molecules are useful for modelling and calculations of DNA damage. Monte Carlo track structure codes KURBUC and PITS99 were used to generate tracks of primary electrons 10 eV to 1 MeV, and ions 1 keV μm(-1) to 300 MeV μm(-1) energies. Distribution of absolute frequencies of energy depositions in volumes with diameters of 1-100 nm randomly positioned in unit density water irradiated with 1 Gy of the given radiation was obtained. Data are presented for frequency of energy depositions and microdosimetry quantities including mean lineal energy, dose mean lineal energy, frequency mean specific energy and dose mean specific energy. The modelling and calculations presented in this work are useful for characterisation of the quality of radiation beam in biophysical studies and in radiation therapy.     

Systemic effects and withdrawal syndrome in chronic users of corticosteroids]

Three newly found vibrational levels at energies Te(v) = 45127.88(3), 51900.40(4), and 52604.95(3) cm-1 allow the first application of resonance-enhanced multiphoton ionization for detecting the SO radical in its low-energy singlet states, a1Delta and b1Sigma+. The analysis of the spectra is based on the observation of 10 rotationally resolved bands starting from a1Delta v = 0, 6 ellipsis 11 and b1Sigma+ v = 8, covering a typical range of J = 5 ellipsis 40 or 50. Population of these SO singlet states has been achieved by two-photon dissociation of SO2 in a molecular beam environment, applying wavelengths in the 248 to 291 nm range. This paper presents an analysis of the rotational, vibrational, and electronic properties of the new levels. Reviewing earlier works on the singlet states of SO, a revised term energy scheme is provided which connects the singlet and triplet systems of the molecule. Copyright 1998 Academic Press.