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We attempted direct detection of elastic distortion in α-Fe particles embedded in a Cu matrix and surrounded by Orowan loops, by utilizing moire fringes which were formed by nearly parallel matrix {111} Cu and particle {110} Fe planes. Foils for transmission electron microscopy were made out of a work hardened Cu-Fe sample. Rotation angles of the moire fringes, which gave the inclination angles of the particle {110} Fe planes to the matrix {111} Cu planes, were examined before and after foil annealing. The annealing rotated the panicle {110} Fe planes in the same direction for almost all the panicles examined, indicating the decrease in the elastic distortion of the panicles due to the disappearance of the Orowan loops. The measured rotation angles on the annealing were in the correct order of magnitude predicted by an elasticity calculation, although the absolute magnitude was smaller in the measurement.

The contraction ratios along [110] and [001] were calculated for a number of cubic crystals by means of the generalized stress and strain relations expressed in the elastic compliances on the assumption that the single crystals were subjected to uniaxial loading along [110]. It was revealed that the contraction ratios along [110] take negative values for many crystals, whose anisotropy factors are greater than about 2. For example, negative values of −0.53 and −0.10 were obtained for β-brass and copper respectively. The pure bending tests employing holographic interferometry were conducted to confirm this phenomena using copper single crystals. In this study, the expression describing the morphology of contour lines of the anisotropic materials subjected to pure bending was presented in terms of the elastic compliances. It was suggested from the expression that, as contour lines, the positive values of the contraction ratio provide hyperbolas, on the contrary, the negative values provide ellipses. The experimental results were in good agreement with the results expected analytically.

We attempted to predict the severity of cerebral ischemia, prior to permanent occlusion of a common carotid artery (CCA), in the gerbil by measuring the diameter of the distal CCA before and during temporary ligation and correlated the severity of cerebral ischemia and the pattern of cerebral circulation. All gerbils with reduction of the diameter over 44% after temporary occlusion developed severe neurological signs following permanent ligation. These gerbils lacked any connection between the left and right anterior cerebral arteries (ACA) and the pericallosal arteries originated from the ACA of the occluded side. No gerbils with reduction of less than 30% developed neurological signs and those gerbils possessed a definite anastomosis between the ACAs from both sides. Six of 7 gerbils without connection between the ACAs whose pericallosal arteries originated from the ACA of the non-occluded side proved to be moderately symptomatic. It was concluded that we could reliably predict severely symptomatic and moderately symptomatic gerbils with specific cerebral circulation patterns prior to permanent occlusion of the CCA. The preselected 'stroke-prone' gerbils should be useful for the investigation of cerebral ischemia and the evaluation of pharmacological agents.

Introduction The aim of this study was to examine the association between mild parkinsonian signs (MPS), cerebral small-vessel disease (SVD), and total SVD burden in patients with vascular risk factors. Methods We performed a cross-sectional study among 268 patients with vascular risk factors but without parkinsonism or dementia (71.0 ± 7.8 years, 63% male). MPS was evaluated via Unified Parkinson's Disease Rating Scale Part III. Brain MRI was used to determine SVD (cerebral microbleeds [CMBs], lacunar infarctions [LIs], and white matter hyperintensities [WMH]). The presence of each SVD feature was indicated by the total SVD score. Logistic regression analyses were performed adjusting for age, sex, history of stroke, hypertension, diabetes mellitus, and dyslipidemia. Results In a multivariate analysis, we found that the presence of CMBs, deep CMBs, mixed (in the basal ganglia and thalamus) LIs, periventricular hyperintensities (PVH), and deep WMH (DWMH), and total SVD score were significantly associated with MPS, whereas strictly lobar CMBs and other LIs (in strictly basal ganglia or strictly thalamus) were not. We also found a significant association between mixed LIs, PVH, DWMH and total SVD score and gait/balance function, between PVH and rigidity, and between mixed LIs and bradykinesia. Among elderly participants (≥73years), the association of total SVD score, deep CMBs, mixed LIs, and PVH, with MPS remained significant. Conclusion Our results provide additional evidence that SVD including CMBs, and especially total SVD burden, might be a surrogate marker for MPS and support the contribution of hypertensive microangiopathy as the underlying etiology.

According to the anisotropic elasticity theory, the contraction ratios along [110] take negative values for a number of metals when the single crystals are subjected to uniaxial forces along [110]. The pure bending tests employing holographic interferometry were conducted to confirm this phenomena using copper single crystals. In this study , the expression describing the morphology of contour lines of the anisotropic materials subjected to pure bending was presented in terms of the elastic compliances. It was suggested from this expression that, as contour lines, the positive values of contraction ratio provide hyperbolas, on the contrary, the negative values provide ellipses. The experimental results were in good agreement with the results expected analytically.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We investigated the neuronal distribution of microtubule-associated protein 2 in gerbil brain and monitored the progression of ischemic damage immunohistochemically by using this protein as a dendritic marker. The reaction for microtubule-associated protein 2 in normal gerbil brain clearly visualized neuronal soma and dendrites but other structures such as axonal bundles, glia and endothelial cells exhibited little immunoreactivity. In a reproducible gerbil model of unilateral cerebral ischemia, we could detect the ischemic lesions as early as 3 min after right common carotid occlusion at the subiculum-CA1 region of the ipsilateral hippocampus as faint loss of the reaction in the dendrites. After ischemia for 30 min, the ischemic lesions were clearly detected as loss of the reaction in the nerve cell bodies, dendrites and the neuropil in the hippocampus, cerebral cortex, thalamus and the caudoputamen. Although the mechanism for prompt disappearance of the immunohistochemical reaction for microtubule-associated protein 2 is not clear, the present investigation suggests that dendrites in the vulnerable regions may be quite susceptible to ischemic stress and that the immunohistochemical procedure for microtubule-associated protein 2 may be very useful for demonstration of dendritic damage in various pathophysiological states of the central nervous system.

The relationship between the bulk and surface related sources of acoustic emission (AE) is studied by analysing the effect of geometry and the surface on AE-level. The AE maximum at the onset of plastic deformation is found to be proportional to the surface area. It is concluded that AE during early stages of plastic deformation of both single and polycrystals is largely determined by the surface related defects.

The fatigue performance of the fine-grain 5056 Al-Mg alloy processed by severe plastic deformation through equal-channel angular pressing (ECAP) is assessed in both stress- and plastic strain-controlled experiments. Compared to its conventional counterpart, the ECAP material exhibits a high tensile and low-cyclic fatigue strength under constant stress amplitude. However, its fatigue life under strain-controlled conditions is notably shorter than that of the O-temper specimens. Despite severe pre-straining of the specimen during ECA-pressing, cyclic softening was found to be rather small. It is shown that the mechanical characteristics obtained after ECAP can be significantly improved during short time annealing at moderate temperatures (150°C, 15 min) after fabrication. Such heat treatment is supposed to recover partially the grain boundary region, which has been most heavily distorted during processing. Mechanisms of fatigue in ECA-processed materials are discussed within a framework of a simple one-parametric model of dislocation kinetics.

Aortic arch atherosclerotic lesions can cause ischemic cerebrovascular disease (ICVD). The association between carotid and aortic atherosclerosis was examined, and it was investigated whether noninvasive carotid evaluation aids in the identification of aortic lesions as potential ICVD risk. The subjects comprised 147 patients with ICVD who had undergone carotid ultrasonography and transesophageal echocardiography. Carotid and aortic arch atherosclerosis was evaluated by measuring the maximum intima - media thickness (IMT), with aortic IMT of at least 4 mm, mobile plaques and/or ulcers defined as complex aortic lesions with potential ICVD risk. Carotid IMT was linearly associated with aortic IMT (r=0.53, p

The nature of the Bauschinger effect in metallic materials is explained mainly by two different approaches. One takes account of the internal stresses related to macroscopic residual stresses between the neighboring grain which shows different hysteresis loops. The other approach is based on the long-range elastic interactions between dislocations creating microscopic stress field (see the review (1) for details). Obviously, these two mechanisms operate simultaneously in a common polycrystalline material. Discrimination between these two mechanisms is not quite straightforward, and the magnitudes of individual contributions to the Bauschinger effect are still ambiguous. In order to separate these two contributions, it might be convenient to compare the results obtained on a bicrystal having a longitudinal grain boundary with those of constituent single crystals. However, a technical problem arises in experiment with bicrystals. If the flow stresses of constituent grains are different, the deviation in the axial stress gives rise to a certain bending moment leading to inhomogeneous stress and strain distribution in the specimen. In order to diminish this bending moment, we employed a tricrystal with two longitudinal parallel boundaries as shown schematically in Fig. 1. The grains at both ends of the specimens are of the same orientation and dimension. In the present study, the cyclic deformation tests were carried out on the tricrystal and its constituent single crystals. The Bauschinger effect during the cyclic deformation was compared between the tricrystal and the constituent single crystals by means of the Bauschinger energy parameter bE (2) and the Bauschinger stress parameter bs (3). The authors attempted to understand the Bauschinger effect in the cyclically-deformed tricrystal by mixing the corresponding pairs of hysteresis loops of the constituent grains.

今回，我々は脳転移を契機に発見されたS状結腸癌に対し転移巣および原発巣切除を行い，長期生存を得た症例を経験したので報告する．症例は54歳の女性で，2005年11月に頭痛と右上下肢の痺れ，脱力を主訴に当院脳外科を受診した．造影MRIで造影効果を伴う直径15 mm大の円形腫瘍と周囲の広範な浮腫を認めた．腫瘍マーカーはCA19-9が58 U/mlと軽度上昇していた．腹部CTでS状結腸の壁肥厚と所属リンパ節の腫大を認め，S状結腸癌とそれによる脳転移が疑われた．同月，神経症状の増悪のため脳外科での腫瘍切除を先行し，高分化型腺癌の診断に至り外科転科となった．同12月に高位前方切除D2郭清を施行，最終診断はS/C，type2，tub1，53×45 mm，pSS，ly1，v1，pN1，sH0，cP0，cM1，fStageIVであった．UFT＋LVによる追加治療を1年継続し，現在51か月の無病再発期間を得ている．

症例は54歳の女性で，2001年9月に当院で右側スピーゲルヘルニアに対して修復術を施行した．2007年9月に左中腹部膨隆を主訴に当科を受診した．身体所見上，左中腹部に腹圧にて出現する膨隆を触知し圧痛は認めなかった．還納は容易であり，直径2 cm大のヘルニア門を触診した．前回手術痕は右側対称に認められた．CTでは左腹直筋外縁に腹腔内から皮下に脱出するヘルニア嚢を認めた．以上より，左側スピーゲルヘルニア異時性発症と診断し，待機的に全身麻酔下で手術を施行した．ヘルニア門は直径1.5×1.5cm大で，腹直筋と内外腹斜筋および腹横筋間の癒合が完全欠損したタイプであった．Composix® Kugel® patchを用いて修復を行った．術後経過は良好で，第8病日に退院した．術後15か月が経過し，再発は認めていない．今回，我々は非嵌頓異時性両側スピーゲルヘルニアの1例を経験したので，文献的考察を含め報告した．

Acoustic emission (AE) is investigated during cycling at a constant plastic strain amplitude of ultrafine-grain (UFG) copper produced by severe plastic deformation, aiming at detailed characterization of AE in the time and frequency domain and clarification of fatigue damage mechanisms. The results of AE analysis in UFG copper are compared with those obtained in conventional polycrystals and single crystals. It is shown that fatigue damage and corresponding AE in UFG copper is controlled by three main mechanisms: large-scale shear banding, mode I tensile crack opening and mode II shear crack propagation. No AE that could be associated with ordinary dislocation mechanisms typical for conventional coarse-grain metals was detected in the UFG state. A close connection between strain localization, crack nucleation and grain boundaries in UFG materials is emphasized. It is shown that annealing at a moderate temperature of UFG materials fabricated by severe plastic deformation can reduce the degree of s...