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Background and Aim We evaluated whether diffusion kurtosis and tensor imaging (DKI/DTI) could reveal microstructural alterations in the brains of patients with functional gastrointestinal disorders (FGIDs), and whether imaging findings were correlated with health‐related quality of life (HRQOL). Methods Twelve patients with FGIDs fulfilling the Rome IV criteria, and seven healthy controls were examined using a 3 T magnetic resonance (MR) scanner. Tract‐based spatial statistics and regions of interest analyses were performed to compare the mean kurtosis (MK), fractional anisotropy (FA), and mean diffusivity (MD) between patients with FGIDs versus controls. HRQOL was assessed in patients with FGIDs using the eight‐item short form of the Medical Outcome Study Questionnaire (SF‐8) and the Gastrointestinal Symptom Rating Scale. Results Patients with FGIDs had extensive, widespread regions of reduced MD in the white matter in comparison with healthy controls, whereas no significant differences were observed in MK and FA. No significant differences in deep gray matter for the MK, FA, and MD values were observed between patients with FGIDs and controls. In patients with FGIDs, the FA values in the globus pallidus had a significant and negative correlation with SF‐8 (a mental component summary) (r = −0.797, P = 0.01 uncorrected for multiple comparisons). Conclusions DKI/DTI can help identify microstructural white matter alterations in patients with FGIDs. The FA values in the globus pallidus may be useful for a severity assessment of FGIDs., We evaluated whether DKI/DTI could reveal microstructural alterations in the brains of patients withFGIDs, and if imaging findings were correlated with HRQOL. Patients with FGIDs had extensive, widespread regions of reduced MD in the white matter in comparison with healthy controls. In FGIDs, the FA values in the globus pallidus had a significant and negative correlation with SF‐8 (a mental component summary). The FA values in the globus pallidus may be useful for a severity assessment of FGIDs.

Differentiation between multiple system atrophy (MSA) and other spinocerebellar degenerations showing cerebellar ataxia is often difficult. Hence, we investigated whether magnetic resonance diffusion kurtosis imaging (DKI) could detect pathological changes that occur in these patients and be used for differential diagnosis.Thirty-six subjects (12 patients with MSA accompanied by predominant cerebellar ataxia [MSA-C], 10 patients with spinocerebellar ataxias [SCAs] or sporadic adult-onset ataxia of unknown etiology [SAOA], and 14 healthy controls) were examined using 1.5- or 3-T magnetic resonance scanners. From the DKI data, the mean kurtosis, fractional anisotropy, and mean diffusivity values of the pontine crossing tract (PCT), middle cerebellar peduncle, and cerebellum were automatically measured, and the ratios against the values of the corpus callosum were calculated.We found significant decreases in mean kurtosis and fractional anisotropy ratios in the PCT and middle cerebellar peduncle, and a significant increase in the mean diffusivity ratio in the PCT in the MSA-C group, as compared with the SCA/SAOA and control groups (p0.027-0.001). Among these metrics, there were no significant differences in the diagnostic performance. By contrast, the ratios in the cerebellum showed no significant differences between the MSA-C and SCA/SAOA groups but were significantly altered when compared with the controls (p0.001).Quantitative DKI analyses can be used to differentiate between patients with MSA-C and those with SCA/SAOA.

OBJECTIVES Nasal passages adjust the temperature of inhaled air to reach the required body temperature for the lungs. The nasal regions of primates including humans are believed to have experienced anatomical modifications that are adaptive to effective conditioning of the atmospheric air in the habitat for a given species. Measurements of the nasal temperature are required to understand the air-conditioning performance for a given species. Unfortunately, repeated direct measurements within the nasal passage have been technically precluded in most nonhuman primates. MATERIALS AND METHODS Computational fluid dynamics (CFD) simulation is a potential approach for examining the temperature profile in the nasal passage without any direct measurements. The CFD simulation model mainly comprises a computational model to simulate physiological mechanisms and a wall model to simulate the nasal passage's anatomical and physical properties. We used a computational model developed for humans and examined corrections for the developed wall model based on human properties for predicting its performance in Japanese macaques. RESULTS This study confirmed that the epithelium layer thickness of the wall model affects the accuracy of the predictions for macaques. A convenient correction of the thickness based on body mass allows us to simulate the actual air temperature profile in macaques' nasal passage. DISCUSSION The CFD simulations of the wall model corrected with body mass can be applied to other nonhuman primates and mammals. This convenient corrective approach allows us to examine the functional contributions of a specific morphology to the air-conditioning performance without any direct measurements to improve our understanding of primates' functional morphology and physical adaptations to the temperature environment in their habitat.

There was an error published in [Journal of Experimental Biology (2015) 218, 2394-2401][1] ([doi:10.1242/jeb.118059][2]). The authors mistakenly transposed the citations of two references on p. 2400 in the Materials and Methods. The corrected text before equations 12 and 13 should read: ‘The

Cerebrovascular reactivity (CVR) to acetazolamide (ACZ) on single-photon emission computed tomography (SPECT) can be used to assess the severity of chronic cerebral ischemia; however, this is an invasive method. We examined whether whole-brain magnetic resonance angiography (MRA) at 7T could non-invasively detect impaired CVR in patients with chronic cerebral ischemia by demonstrating the leptomeningeal collaterals (LMCs).Fifty-seven patients with symptomatic unilateral cervical stenosis underwent whole-brain time-of-flight MRA at 7T and cerebral perfusion SPECT before/after the ACZ challenge. MRA images were visually assessed based on 6-point grading systems to evaluate the development of LMCs toward the middle cerebral artery (MCA) and antegrade flow of MCA. CVR of the affected side was calculated from the SPECT data. Subsequently, we compared the LMC grades on MRA with CVR on SPECT.CVR was significantly lower in grades ≥ 2 of LMCs than in grades 0-1 (P 0.05) when applying LMCs from the anterior cerebral artery (ACA) and/or posterior cerebral artery (PCA). These differences were more evident than those in the grading of the antegrade MCA flow. The LMC grades from ACA/PCA readily detected reduced CVR (18.4%) with a sensitivity/specificity of 0.79/0.82.The development of LMCs on whole-brain MRA at 7T can non-invasively detect reduced CVR with a high sensitivity/specificity in patients with unilateral cervical stenosis.

In stroke patients, muscle tone on the unaffected side is often increased during voluntary tasks. This is known as a mirror movement and might be an impediment to function recovery, but its neural background is still unclear. In this study, we investigated the effect of unilateral muscle hypertonia on ipsilateral cortical activity and contralateral motor function. Fourteen right-handed healthy young subjects lifted a weight of 10% body weight with the right upper limb to increase muscle tone (weight task), while no weight lifting was set as the control 'nonweight' task. We recorded the motor-evoked potential (MEP), resting motor threshold and H-reflex from the left flexor carpi radialis muscle during both tasks. To estimate the functional effect of the weight task, subjects performed the 'Purdue pegboard test', consisting of examination for 30 seconds (peg-30) and assembly for 60 seconds (peg assembly). Left-hand grip strength was also measured. When subjects performed the weight task, the MEP amplitude increased significantly and the MT decreased significantly. There was no significant difference of H-reflex amplitude between the two tasks. No significant difference of the peg-30 score was observed between weight and nonweight tasks, but the peg assembly score was significantly lower during the weight task. Grip strength showed a significant increase during the weight task. These results indicate that the present weight load model may have the potential to advance our understanding of the mechanisms underlying mirror movements after stroke.

Background The severity of chronic cerebral ischemia can be assessed using cerebrovascular reactivity (CVR) to acetazolamide (ACZ) challenge, which is measured by single-photon emission computed tomography (SPECT); however, this is an invasive method. We investigated whether intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) can assess impaired CVR in preoperative patients with chronic cerebral ischemia and compared it to SPECT-CVR. Methods Forty-seven patients with unilateral cervical carotid artery stenosis underwent diffusion-weighted MRI with 11 b-values in the range of 0–800 s/mm2 and cerebral perfusion SPECT with the ACZ challenge. The perfusion fraction (f) and diffusion coefficient (D) of the IVIM parameters were calculated using a bi-exponential model. The f and D values and these ratios of the ipsilateral middle cerebral artery territory against the contralateral side were compared with the CVR values of the affected side calculated from the SPECT data. Results The IVIM-f and D values in the affected side were significantly higher than those in the unaffected side (median: 7.74% vs. 7.45%, p = 0.027; 0.816 vs. 0.801 10−3mm2/s, p Conclusion The IVIM perfusion parameter, f, can noninvasively assess impaired CVR with high sensitivity and specificity in patients with unilateral cervical carotid artery stenosis.

The short-term joint immobilization induces a decrease of corticospinal excitability; however, detailed time course of the immobilization-induced central nervous system changes and their extent have not yet been clarified. To evaluate the time course of changes in corticospinal excitability during forearm/hand immobilization for 24 h and investigate the effect on muscle strength, adhesive casting tape was used to immobilize the nondominant forearm/hand. The amplitude of the motor-evoked potential of the flexor pollicis brevis muscle induced by transcranial magnetic stimulation was measured during immobilization and after cast removal. The muscle strength was evaluated after the termination of immobilization. The resting motor-evoked potential recorded from flexor pollicis brevis muscle showed a significant decrease 3 h after initiation of immobilization and gradually declined further until the end of immobilization. It then increased over 2 h after cast removal, but was still significantly below baseline. However, no significant difference from baseline was observed at 3 h. Both pinch power and integrated electromyogram were significantly reduced by immobilization, and then gradually returned to baseline after the cast was removed. These results indicate that short-term forearm/hand immobilization rapidly reduces corticospinal excitability, and this change is rapidly reversed after resumption of movement.

Background and Purpose— The oxygen extraction fraction (OEF) is an effective metric to evaluate metabolic reserve in chronic ischemia. However, OEF is considered to be accurately measured only when using positron emission tomography (PET). Thus, we investigated whether OEF maps generated by magnetic resonance quantitative susceptibility mapping (QSM) at 7 Tesla enabled detection of OEF changes when compared with those obtained with PET. Methods— Forty-one patients with chronic stenosis/occlusion of the unilateral internal carotid artery or middle cerebral artery were examined using 7 Tesla-MRI and PET scanners. QSM images were obtained from 3-dimensional T2*-weighted images, using a multiple dipole-inversion algorithm. OEF maps were generated based on susceptibility differences between venous structures and brain tissues on QSM images. OEF ratios of the ipsilateral middle cerebral artery territory against the contralateral side were calculated on the QSM-OEF and PET-OEF images, using an anatomic template. Results— The OEF ratio in the middle cerebral artery territory showed significant correlations between QSM-OEF and PET-OEF maps ( r =0.69; P r =0.79; P =0.004), although showing significant systematic biases for the agreements. An increased QSM-OEF ratio of >1.09, as determined by receiver operating characteristic analysis, showed a sensitivity and specificity of 0.82 and 0.86, respectively, for the substantial increase in the PET-OEF ratio. Absolute QSM-OEF values were significantly correlated with PET-OEF values in the patients with increased PET-OEF. Conclusions— OEF ratios on QSM-OEF images at 7 Tesla showed a good correlation with those on PET-OEF images in patients with unilateral steno-occlusive internal carotid artery/middle cerebral artery lesions, suggesting that noninvasive OEF measurement by MRI can be a substitute for PET.

Objective To investigate the correlation between changes of contralesional cortical excitability evaluated by transcranial magnetic stimulation (TMS) and functional recovery in patients with hemiparetic stroke. Methods Eight inpatients (mean age: 75.9±13.8 years) with mild to moderate hemiparesis were enrolled. TMS was delivered to the optimal scalp position over the contralesional (ipsilateral to the paresis) primary motor cortex (M1) to activate the unaffected flexor carpi radialis muscle (FCR) while the patient picked up a wooden block with the affected hand. The amplitude of the motor-evoked potential (MEP) was measured and then was divided by the resting MEP amplitude (MEP ratio). For evaluation of motor function, we tested grip strength (GS), performed the upper extremity motor section of the Fugl-Meyer Assessment (FMA-UE), and performed the Purdue Pegboard Test (PPT) when the patients were admitted to our hospital (T1) and 2 months after admission (T2). Results The MEP ratio was significantly decreased at the second examination. The partial correlations between the MEP ratio and FMA-UE at T1, and PPT of an affected hand at T2 were observed while controlling for the period after stroke onset as the confounding variable. Conclusion The reduction of contralesional cortical hyperactivity is related to the functional recovery in part, but not related with the period after stroke onset. This suggests that enhanced reduction of contralesional M1 hyperactivity contributes to functional recovery after stroke.

Purpose The Bayesian estimation algorithm improves the precision of bolus tracking perfusion imaging. However, this algorithm cannot directly calculate Tmax, the time scale widely used to identify ischemic penumbra, because Tmax is a non-physiological, artificial index that reflects the tracer arrival delay (TD) and other parameters. We calculated Tmax from the TD and mean transit time (MTT) obtained by the Bayesian algorithm and determined its accuracy in comparison with Tmax obtained by singular value decomposition (SVD) algorithms. Methods The TD and MTT maps were generated by the Bayesian algorithm applied to digital phantoms with time-concentration curves that reflected a range of values for various perfusion metrics using a global arterial input function. Tmax was calculated from the TD and MTT using constants obtained by a linear least-squares fit to Tmax obtained from the two SVD algorithms that showed the best benchmarks in a previous study. Correlations between the Tmax values obtained by the Bayesian and SVD methods were examined. Results The Bayesian algorithm yielded accurate TD and MTT values relative to the true values of the digital phantom. Tmax calculated from the TD and MTT values with the least-squares fit constants showed excellent correlation (Pearson's correlation coefficient = 0.99) and agreement (intraclass correlation coefficient = 0.99) with Tmax obtained from SVD algorithms. Conclusions Quantitative analyses of Tmax values calculated from Bayesian-estimation algorithm-derived TD and MTT from a digital phantom correlated and agreed well with Tmax values determined using SVD algorithms.

Supplemental Digital Content is available in the text., Background and Purpose— The frictional force because of blood flow may dislodge masses present on the surface of a plaque. Such frictional force is calculated as wall shear stress (WSS) using computational fluid dynamics. The aims of the present study were to determine whether, in addition to carotid plaque intensity on T1-weighted magnetic resonance (MR) imaging, WSS calculated using computational fluid dynamics analysis for carotid arteries is associated with development of an embolism during exposure of carotid arteries during carotid endarterectomy. Methods— One hundred patients with internal carotid artery stenosis (≥70%) underwent carotid plaque imaging with MR, and 54 patients with a vulnerable plaque (intraplaque hemorrhage or lipid/necrotic core) displayed as a high-intensity lesion underwent additional cervical 3-dimensional MR angiography. The maximum value of WSS within the most severe stenotic segment of the internal carotid artery was calculated using MR angiography. Transcranial Doppler monitoring of microembolic signals (MES) in the ipsilateral middle cerebral artery was performed during carotid endarterectomy. Results— Although none of the 46 patients with a nonvulnerable carotid plaque had MES during exposure of carotid arteries, 24 of the 54 patients with a vulnerable carotid plaque (44%) had MES. Logistic regression analysis showed that higher plaque intensity (P=0.0107) and higher WSS (P=0.0029) were significantly associated with the development of MES. When both cutoff points of plaque intensity and WSS in the receiver operating characteristic curves for predicting development of MES were combined, specificity (from 63% to 93%) and positive predictive value (from 66% to 90%) became greater than those for plaque intensity alone. Conclusions— In addition to carotid plaque intensity on T1-weighted MR imaging, WSS calculated using computational fluid dynamics analysis for carotid arteries is associated with development of an embolism during exposure of carotid arteries during carotid endarterectomy.

We compared the time-course of satellite cell (SC) activation between eccentric and concentric contractions in the vastus lateralis (VL) muscle after step exercise. Young adults participated in a 30-min step up/down exercise which mainly involved concentric contractions with the right VL muscle and eccentric contractions with the left VL muscle. The concentric and eccentric contraction phases of the VL muscles were identified by changes in the electromyogram (EMG) and knee joint angle. Biopsy samples were taken from both VL muscles at three time periods: before the exercise and 2 and 5 days after the exercise. We found that the numbers of SCs were significantly increased in the type IIa fibers of the left VL at 2 and 5 days after the exercise. The expression of both hepatocyte growth factor (HGF) and myogenic differentiation 1 (MyoD) mRNA had significantly increased in the left VL at 2 and 5 days after the exercise and in the right VL at 5 days after the exercise. The expression of transient receptor potential canonical (TRPC) 1 mRNA also increased in the left VL at 2 days after exercise. These results indicate that eccentric contraction can effectively activate SC proliferation for up to 5 days after exercise. Similar changes in HGF, MyoD and TRPC1 mRNA expression suggest that HGF/c-Met signal activation through cation influx has a major impact on skeletal muscle SC activation in response to eccentric exercise.

Background: Infarcts in the lateral striate artery (LSA) territory can be caused by several pathological changes, including lipohyalinosis and microatheroma. However, fluid dynamic effects on these changes remain unknown. Thus, we investigated whether the fluid dynamic metrics of the LSAs were altered in patients with acute ischemic stroke using computational fluid dynamics (CFD) analysis. Methods: Fifty-one patients with acute ischemic stroke confined in the basal ganglia and/or corona radiata underwent high-resolution magnetic resonance angiography (HR-MRA) at 7T. We performed CFD analyses to obtain indices including the wall shear stress (WSS), WSS gradient (WSSG), and flow velocity (FV) and compared these values between the ipsilesional and contralesional sides in the patients with infarcts in the LSA or non-LSA territories. Results: In patients with LSA-territory infarcts, the WSS, WSSG, and FV values were significantly lower in the ipsilesional LSAs than in the contralesional LSAs (P = .01-.03), while these values in the proximal middle cerebral arteries showed no significant lateralities. In contrast, in patients with non-LSA-territory infarcts, there were no significant lateralities in the metrics between the ipsilesional and contralesional sides. Conclusions: The CFD analyses using HR-MRA revealed significantly low WSS and WSSG values of the ipsilesional LSAs compared with that of the contralesional side in patients with LSA-territory infarcts, suggesting that fluid dynamic factors of LSAs can be one of the risk factors for LSA-territory infarctions.

Knowing the detailed responses associated with the environment of our closest living relative allows us to comprehend more data about apes which may be useful to conclude hypotheses regarding the behavior of early hominins. The difference between humans and apes toward the adaptability to the living environment is caused by the difference among both bodies’ biological functions such as the nasal cavity biological function. Indeed, the temperature and the humidity of the inhaled air are adjusted by the heat and the water exchange in the nasal cavity wall's surface. In order to understand the nasal cavity functions for the adjustment of the temperature and the humidity of the inhaled air, it is necessary to know the flow distribution during breathing process. To do so, a noninvasive measurement is hard to be held. Therefore, this study simulates a laminar steady airflow, in a realistic adult male chimpanzee's nasal cavity shape reconstructed from Computed Tomography (CT) images, using CFD. So far, an airflow study related to chimpanzee's nasal cavity has not been previously reported. We present for the first time a computer simulation of a realistic chimpanzee's nasal cavity flow. This study uses a model with heat and humidity transport. The governing equations include a continuum equation and the equations describing momentum, energy, and water transport. The findings are in agreement with the expected results directly inferred from the biological function of the nasal cavity itself.

We are flat-faced hominins with an external nose that protrudes from the face. This feature was derived in the genus Homo, along with facial flattening and reorientation to form a high nasal cavity. The nasal passage conditions the inhaled air in terms of temperature and humidity to match the conditions required in the lung, and its anatomical variation is believed to be evolutionarily sensitive to the ambient atmospheric conditions of a given habitat. In this study, we used computational fluid dynamics (CFD) with three-dimensional topology models of the nasal passage under the same simulation conditions, to investigate air-conditioning performance in humans, chimpanzees, and macaques. The CFD simulation showed a horizontal straight flow of inhaled air in chimpanzees and macaques, contrasting with the upward and curved flow in humans. The inhaled air is conditioned poorly in humans compared with nonhuman primates. Virtual modifications to the human external nose topology, in which the nasal vestibule and valve are modified to resemble those of chimpanzees, change the airflow to be horizontal, but have little influence on the air-conditioning performance in humans. These findings suggest that morphological variation of the nasal passage topology was only weakly sensitive to the ambient atmosphere conditions; rather, the high nasal cavity in humans was formed simply by evolutionary facial reorganization in the divergence of Homo from the other hominin lineages, impairing the air-conditioning performance. Even though the inhaled air is not adjusted well within the nasal cavity in humans, it can be fully conditioned subsequently in the pharyngeal cavity, which is lengthened in the flat-faced Homo. Thus, the air-conditioning faculty in the nasal passages was probably impaired in early Homo members, although they have survived successfully under the fluctuating climate of the Plio-Pleistocene, and then they moved "Out of Africa" to explore the more severe climates of Eurasia., ヒトの鼻腔機能はチンパンジーに及ばない -それでも、原人は出アフリカを遂げた-. 京都大学プレスリリース. 2016-03-25.

The nasal cavity performs several important functions for the inhaled air, such as temperature and humidity adjustments. Although it is necessary to obtain velocity, temperature, and humidity distributions during inhalation in order to understand the nasal cavity's functions, it is difficult to measure them noninvasively in the nasal cavity. Therefore, we have continued to study nasal flow simulation with heat and humidity transport. In such a simulation, the governing equations include a continuum equation and the equations describing momentum, energy, and water transport. The temperature and humidity of the inhaled air are adjusted by heat and water exchange on the nasal cavity wall's surface. Therefore, in the simulation, these roles of the wall in the energy and water transport equations were included as the boundary conditions. Although in related studies of nasal flow simulation with heat and humidity transport, the nasal cavity wall's surface temperature and humidity were constant, here they were treated as degrees of using Newton's cooling law. A flow including temperature and humidity in a realistic human nasal cavity shape was simulated. The simulation results agreed well with the measurements reported by Keck at al. Therefore, this study concludes that our model can simulate the heat and humidity exchange occurring in the nasal cavity. In addition, it was found that the temperature and humidity adjustment functions worked effectively in the front and narrow regions of the nasal cavity.

Electron projection lithography (EPL) is a realistic technology for the 65nm node and below, as a complementary technology of optical lithography especially for contacts and gate layers because of its high resolution and large process margin. Nikon has developed an EPL exposure tool as an electron-beam (EB) stepper and the first generation EB stepper; NSR-EB1A is now almost completed as an R&D tool for the 65nm technology node. Using a ϕ200mm reticle, a 20mm×25mm exposure field is realized. Full-field exposure performance of NSR-EB1A is shown. A 70nm isolated line and 1:1 nested lines are simultaneously resolved, as are 50nm 1:2 nested lines. 60nm contact holes are resolved with a depth of focus over a 10μm range and dosage window over ±6%. Stitching accuracy is about 20nm (3σ) and the single machine overlay is about 30nm (mean + 3σ). These data mean sufficient performance for device manufacturing of the 65nm technology node. The concept of a large subfield is one candidate for resolution and throughput e...

BACKGROUND Stent placement for cerebral aneurysms leads to a decrease in blood flow. This occurs not only through the direct obstruction of flow but also by the expansion of the parent artery. The latter has been observed in several clinical studies. OBJECTIVE The goal of this study was to clarify the effects of parent artery expansion after stent treatment on the following: 1) decrease in blood flow to an aneurysm, 2) wall shear stress (WSS), and 3) oscillatory shear index (OSI). METHODS The parent artery geometry constructed U-shape. The aneurysm location with respect to the U-shaped parent artery was determined according to previous clinical data. We performed calculations in unsteady-state situations using constructed models. RESULTS Parent artery expansion with stent reduces blood inflow to an aneurysm and WSS of the aneurysm wall, in addition to increasing OSI. The aneurysm position affects the decrease of the inflow rate and WSS ratio and increases the OSI ratio. Expansion causes the majority of effects on flow reduction inside an aneurysm model. Thus, the expansion effects of all samples should not be neglected. CONCLUSION These data suggest that parent artery expansion and its effect should be measured and included in the total decrease in blood flow. Parent artery expansion may induce intimal hyperplasia, thus increasing the thickness of the aneurysm wall.

The aging society has rapidly progressed worldwide and the mortality and morbidity rates of aortic diseases are increasing. In particular, aortic aneurysm and aortic dissection are serious disorders. These may be fatal if their diagnosis and treatment are delayed. In 2006, guideline for the diagnosis and treatment of aortic aneurysm and aortic dissection was established in Japan [1]. In 2010, a guideline for the diagnosis and management of patients with thoracic aortic diseasewas established in the United States[2]. These guidelines pay particular attention to the diagnosis and treatment of aortic diseases. We investigated the possibility of estimating timedependent changes in these diseases using Computational Fluid Dynamics (CFD) simulation. This chapter describes the numerical simulations used for ulcer-like projections due to aortic dissections with complete thrombosis. By combining the results of CFD and diagnostic imaging, we can anticipate future improvements in diagnosis.

Cerebral aneurysms (CA) are pathological dilations of the cerebral artery walls, which mostly occur at the circle of Willis. The incidence of CA has been estimated to be between 1% and 8 % among western populations. CA has rupture mortality and morbidity rates are exceedingly high. In the medical field, the stent placement in intracranial artery is call as endovascular treatment. Recently, stent placement as a low invasive therapy is paid to attention for treatment of aneurysm. The role of stent is to prevent blood flow into the aneurysm and to decrease the risk of rupture. Moreover, the effect of only stent on the flow reduction in CA has been reported in Computed Fluid Dynamics (CFD), recently. Moreover, the comparable effect is also reported in experiment. Some results suggested that the blood flow into aneurysm can reduce by only stent placement. Moreover, in generally, he stent porosities investigated under physiologically flow conditions were limited to the rage of 60-86%. And the stent of high porosity such as silk stent and pipeline stent is used for treatment of CA. However, the rupture of CA is reported in the case to use silk stent for CA. Although low or high porosity, it is important to understand flow of stent neighborhood and effect to aneurysm in stent placement. We reconstructed idealize cerebral aneurysm geometry to examine flow pattern and effect to aneurysm by stent placement and analyzed without- and with-stent. As results, the flow cannot divert by stent placement. The flow of wall neighborhood flows into aneurysm. Moreover, average and maximum of pressure distribution and wall shear stress distribution with stent is higher than that of without stent. We examine flow pattern and effect to aneurysm. Although treating by stent placement, there is a possibility of increasing the influence on the aneurysm.

The Hoffman reflex (H-reflex) is a useful tool for studying the functional aspects of the spinal cord without anesthesia and/or damage to the body. H-reflex studies are performed mainly in the hindlimbs. The purpose of the present study was to evaluate the characteristics of the H-reflex in the forelimbs and hindlimbs in rats anesthetized with ketamine-HCl. H- and M-waves were recorded from the interosseous muscles after electrical stimulation of the n. lateral plantar of the hindlimb and n. medialis of the forelimb. Hmax/Mmax values were significantly smaller in the forelimbs than in the hindlimbs. Furthermore, paired-pulse attenuation tended to be stronger in the forelimbs than in the hindlimbs. These findings suggest that control by descending and/or propriospinal pathways is stronger in the forelimbs than in the hindlimbs in rats.

Background: studies are needed which consider CNS-controlled strategies for accommodating perturbed bipedal (Bp) posture and walking. Objective: to demonstrate the suitability of the Japanese monkey, Macaca fuscata, for the above purpose. Setting and subjects: three adult monkeys were operantly trained to use Bp-walking on a moving treadmill belt. On one side of the belt, a rectangular adjustable-height obstacle confronted the ipsilateral leg every 4–6 steps, as determined by belt speed. Methods: animal posture and walking patterns were captured and digitized by two high-speed video systems. Frame-byframe analyses of side- and back-view kinematics were obtained. Results: the monkeys learned quickly to proactively clear the in-coming obstacles by use of a flexible hip-knee-ankle flexion strategy. This featured an appropriate postural adjustment and leg trajectory. In cases where a monkey failed to clear the obstacle, it promptly adopted a defensive posture to avoid falling. There was then a quick return to a posture that allowed the resumption of a Bp gait. Conclusions: when Bp posture and gait are perturbed in a non-human primate model, the prompt adjustment of a flexible hip-knee-ankle flexion strategy and a defensive postural adjustment act together to prevent a fall and enable the speedy resumption of normal Bp posture and gait.

Electron Projection Lithography (EPL) is considered one of promising technologies below 45nm node, especially for contact/via holes and gate layers. EPL has some nice features such as very high resolution to be applied for two device nodes, large process margin associated with large depth of focus and an expected lower CoO. Nikon has been developing an EPL tool, so-called EB Stepper. NSR-EB1A is the first EB Stepper that was designed as R&D tool for 65nm technology node and that was already delivered for Selete (Semiconductor Leading Edge Technologies, Inc.) at Tsukuba in Japan. Nikon has developed two NSR-EB1A tools so far, one system for Selete as a 300mm wafer system and the other for Nikon's development and evaluation as a 200mm wafer system. Both tools have already started to show full performance data and good stability characteristics. The latest EB1A tool performance shows very good results in such data as the resolution of 50nm 2:1 L/S and 60nm 1:1 dense contact holes patterns, stitching accuracy of around 18nm, and overlay accuracy of around 20nm(X+3sigma).

Electron projection lithography (EPL) is one of the promising technologies below the 65 nm node, especially for contact hole and gate layers. Nikon is developing an EPL exposure tool as an electron beam (EB) stepper and the first generation EB stepper is now being manufactured. The voltage of 100 kV is adopted for electron beam acceleration. The subfield size is 0.25 mm×0.25 mm on the wafer and the deflection width of the electron beam is 5 mm on the wafer. The magnification of the projection optics is 1/4. A 5 mm×25 mm area from the φ200 mm reticle can be exposed by the combination of beam deflection and stage scanning motion (dynamic exposure). This area is called “a mechanical stripe.” After one mechanical stripe exposure, the reticle and wafer stages turn around and the next exposure of the adjacent mechanical stripe starts as a scan and stitch stage motion. Finally, a 20 mm×25 mm exposure field from the φ200 mm reticle is exposed. We report the first dynamic exposure in the history of EPL although only a φ100 mm reticle was used. A 5 mm×10 mm area was used as the mechanical stripe and 10 mm×10 mm exposure fields were exposed. 100 nm nested lines were resolved in the entire exposure field and stitching accuracies of 17–18 nm (3σ) are obtained. There remain systematic errors, and stitching accuracy less than 15 nm will be achieved after fine adjustment of the subfield positions. We feel the reality of EPL is now sufficiently proven.

In order to simulate an earthquake shock originating from the earthquake source and the damage it causes to buildings, not only the seismic wave that propagates over a wide region of several 100 km2, but also the building vibrations that occur over a small region of several 10 m2 must be resolved concurrently. Such a multi-scale simulation is difficult because such kind of modeling and implementation by only a specific application are limited. To overcome these problems, a multi-scale weak-coupling simulation of seismic wave and building vibrations using “ppOpen-HPC” libraries is conducted. The ppOpen-HPC, wherein “pp” stands for “post-peta scale”, is an open source infrastructure for development and execution of optimized and reliable simulation codes on large-scale parallel computers. On the basis of our evaluation, we confirm that an acceptable result can be achieved that ensures that the overhead cost of the coupler is negligible and it can work on large-scale computational resources.