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X-ray phase imaging based on X-ray Talbot-Lau interferometry is an emerging nondestructive testing (NDT) method applicable to materials consisting of light elements such as organic and plastic materials. Aiming at future application to the examination of objects carried on conveyor systems, a scanner-type X-ray phase imaging apparatus is developed. Following the verification of the algorithm for phase-scanner image formation (S. Bachche et al., Sci. Rep., 2017), we report on a development with a desk-sized compact configuration and a 200-mm-wide field of view. Gratings used to construct an X-ray Talbot-Lau interferometer are bent and tiled. A scan speed of 9.2 mm/s with a spatial resolution of 0.29 mm is achieved in resultant images of absorption and scattering. Three scattering images are obtained for a carbon fiber reinforced plastic sample by changing its orientation against the gratings to visualize anisotropic fibrous structures.

ZnO films are commonly employed as n-type semiconductors in heterojunctions with PbS colloidal quantum-dot (CQDs) films because of their outstanding optical transparency and electron acceptor properties, yet studies of the impact of ZnO film microstructure, composition, and defect qualities on the solar-cell performance are quite limited. Here we report on the fabrication of ZnO films via pulsed-laser deposition and use these films to investigate how different morphologies affect the PbS CQD solar-cell performance. By modification of the background gas O2 pressures during the ZnO deposition process, the device performance approaching a 7.8% energy conversion efficiency is achieved with an O2 pressure of 100 mTorr. Higher or lower O2 pressures led to significantly lower device efficiency. We employ various materials and device characterizations to highlight the differences in the physical properties introduced by the fabrication oxygen pressure. In particular, we have found that the differences in the type and density of ZnO oxygen defects are the key factors behind the dispersion in solar-cell performances.

In low earth orbit (LEO), atomic oxygen (AO) has shown to cause degradation of organic materials used in spacecrafts. Similar to other metal oxides such as SiO2, Al2O3 and ITO, TiO2 has potential to protect organic materials. In this study, the anatese-type TiO2 thin films were fabricated by a sol-gel method and irradiated with AO. The properties of TiO2 were compared using mass change, scanning electron microscope (SEM), atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmittance spectra and photocatalytic activity before and after AO irradiation. The results indicate that TiO2 film was hardly eroded and resistant against AO degradation. AO was shown to affects only the surface of a TiO2 film and not the bulk. Upon AO irradiation, the TiO2 films were slightly oxidized. However, these changes were very small. Photocatalytic activity of TiO2 was still maintained in spite of slight decrease upon AO irradiation, which demonstrated that TiO2 thin films are promising for elimination of contaminations outgassed from a spacecraft's materials.

Corrugated structures are integral to many types of photoelectronic devices, used essentially for the manipulation of optical energy inputs. Here, we have investigated the gains and losses incurred by this microscale geometrical change. We have employed nanostructured electrode gratings of 600 nm pitch in PbS colloidal quantum dot (PbS-CQD) solar cells and investigated their effect on photovoltaic properties. Solar cells employing grating structure achieved a 32% and 20% increase in short-circuit current density (Jsc) and power conversion efficiency, respectively, compared to nonstructured reference cells. The observed photocurrent increase of the structured devices mainly stems from the enhancement of photon absorption due to the trapping of optical energy by the grating structures. This optical absorption enhancement was particularly high in the near-infrared portion of the sun spectrum where PbS-based solar cells commonly present poor absorption. We have interestingly observed that the open-circuit voltage of all the devices increase with the increase in the absorbed photon energy (at a fixed light intensity), indicating a significant shift in Fermi energy level due to localization of low photon energy generated carriers in the tail of the density of states. We elucidate the role of the grating structure on charge dynamics and discuss the feasibility of these structures for construction of cheap and efficient photovoltaic devices.

To understand cortical mechanisms related to truncal posture control during human locomotion, we investigated hemodynamic responses in the supplementary motor area (SMA) with quadrupedal and bipedal gaits using functional near-infrared spectroscopy in 10 healthy adults. The subjects performed three locomotor tasks where the degree of postural instability varied biomechanically, namely, hand-knee quadrupedal crawling (HKQuad task), upright quadrupedalism using bilateral Lofstrand crutches (UpQuad task), and typical upright bipedalism (UpBi task), on a treadmill. We measured the concentration of oxygenated hemoglobin (oxy-Hb) during the tasks. The oxy-Hb significantly decreased in the SMA during the HKQuad task, whereas it increased during the UpQuad task. No significant responses were observed during the UpBi task. Based on the degree of oxy-Hb responses, we ranked these locomotor tasks as UpQuad > UpBi > HKQuad. The order of the different tasks did not correspond with postural instability of the tasks. However, qualitative inspection of oxy-Hb time courses showed that oxy-Hb waveform patterns differed between upright posture tasks (peak-plateau-trough pattern for the UpQuad and UpBi tasks) and horizontal posture task (downhill pattern for the HKQuad task). Thus, the SMA may contribute to the control of truncal posture accompanying locomotor movements in humans.

Background: Many previous studies have demonstrated that botulinum toxin A (BTX-A) injections satisfactorily reduce spasticity. Nevertheless, BTX-A, with or without an adjuvant therapy, effectively improves the direct functional movement in few patients with spastic upper extremity paralysis. Therefore the present study aimed to determine the effectiveness of task-orientated therapy on spasticity and functional movement by using electromyography-triggered functional electrical stimulation (EMG-FES) after BTX-A injections. Design: Open-label, prospective clinical trial Method: The subjects were 15 patients with spastic paresis (12 male, 3 female; age range, 17―74 years; 14 due to stroke, 1 due to spinal cord injury) who received BTX-A injections. Before the study was started, all subjects had undergone task-orientated therapy sessions with EMG-FES for 4 months. Despite all patients showing a various extent of improved upper extremity function, upper extremity function reached a plateau because of upper extremity spasticity. After BTX-A injection, all patients underwent task-orientated therapy sessions with EMG-FES for 4 months. The outcomes were assessed with the modified Ashworth scale, the simple test for evaluating hand function, box and block test, grip and release test, finger individual movement test, and grip strength. Assessments were performed at baseline and 10 days and 4 months after BTX-A injection. Results: The median modified Ashworth scale score decreased from 2 at baseline to 1 at 10 days and 4 months after BTX-A injection. The finger individual movement test score increased slightly at 10 days (p =0.29) and further increased at 4 months (p

Indium tin oxide (ITO) is the premier choice for transparent conductive electrodes in optoelectronic devices despite its inherent brittleness. Here we report the fabrication of a grating-like structure that obviates ITO’s mechanical limitations while retaining its resistivity and optical qualities. ITO nanopatterned films exhibited a resistivity 90% across the whole visible spectrum range. We demonstrate the nanopatterned ITO retains extraordinary flexibility and durability on heat-sensitive substrates, accommodating cyclic bending to a curvature diameter of at least 3.2 mm for over 50 cycles of compressive and decompressive flexing without significant deterioration of its resistivity or optical properties. Moreover, 2-dimensional extrapolation shows that multiaxial bending is also feasible while maintaining mechanical flexibility, durability, and optical transparency.

The role of optical charge generation and nongeminate recombination on the photocurrent of upright and inverted colloidal-PbS quantum-dot solar cells is investigated. With a controlled active layer thickness, upright (PbS/fullerene) devices are found to present overall better photovoltaic performance relative to inverted devices, notwithstanding the better NIR photoconversion efficiency in the latter. Through detailed analysis and numerical optoelectronic simulations, we show that beyond incidental differences, these two device architectures have fundamentally dissimilar properties that stem from their particular optical generation characteristics and the nature of the recombination processes at play, with the inverted devices affected only by trap-assisted losses and the upright ones suffering from enhanced bimolecular recombination. This study unveils the role of device geometry and inherent material properties on the carrier generation and collection efficiency of the light-generated photocurrent in co...

In recent years, our understanding of motor learning, neuroplasticity and functional recovery after the occurrence of brain lesion has grown significantly. Novel findings in basic neuroscience have provided an impetus for research in motor rehabilitation. The brain reveals a spectrum of intrinsic capacities to react as a highly dynamic system which can change the properties of its neural circuits. This brain plasticity can lead to an extreme degree of spontaneous recovery and rehabilitative training may modify and boost the neuronal plasticity processes. Animal studies have extended these findings, providing insight into a broad range of underlying molecular and physiological events. Neuroimaging studies in human patients have provided observations at the systems level that often parallel findings in animals. In general, the best recoveries are associated with the greatest return toward the normal state of brain functional organization. Reorganization of surviving central nervous system elements supports behavioral recovery, for example, through changes in interhemispheric lateralization, activity of association cortices linked to injured zones, and organization of cortical representational maps. Evidence from animal models suggests that both motor learning and cortical stimulation alter intracortical inhibitory circuits and can facilitate long-term potentiation and cortical remodeling. Current researches on the physiology and use of cortical stimulation animal models and in humans with stroke related hemiplegia are reviewed in this article. In particular, electromyography (EMG) -controlled electrical muscle stimulation improves the motor function of the hemiparetic arm and hand. A multi-channel near-infrared spectroscopy (NIRS) studies in which the hemoglobin levels in the brain were non-invasively and dynamically measured during functional activity found that the cerebral blood flow in the injured sensory-motor cortex area is greatest during an EMG-controlled FES session. Only a few idea is, however, known for the optimal timing of the different processes and therapeutic interventions and for their interactions in detail. Finding optimal rehabilitation paradigms requires an optimal organization of the internal processes of neural plasticity and the therapeutic interventions in accordance with defined plastic time windows. In this review the mechanisms of spontaneous plasticity after stroke and experimental interventions to enhance plasticity are summarized, with an emphasis on functional electrical stimulation therapy.

Objective: In our search for a new augmentation therapy for stroke patients, we administered cilostazol, an antiplatelet agent. Subjects: The patients suffered from mild hemiparesis or cognitive disorder showing reduced cerebral perfusion in the prefrontal cortex. Methods: We evaluated the functional cerebral blood flow (CBF) before and after the administration of cilostazol using near-infrared resonance spectroscopy (NIRS) during a verbal fluency task (VFT). Results: For the patient with cognitive disorder, statistically significant improvements were observed in the number of generated words in the VFT before and after administration of 50 mg cilostazol (p 0.05, Mann-Whitney U test). Another patient without cognitive disorder, however, showed no significant VFT improvement after administration of cilostazol. Effect size data revealed large or very large effects of cilostazol on brain activation (oxy-Hb levels) at the affected side prefrontal cortex for both patients. The patient with cognitive disorder showed significant improvement in VFT performance as well as an increase in bilateral prefrontal CBF after cilostazol administration. Discussion: These findings suggest that, for patients with cerebrovascular lesions suffering from cognitive disorder, cilostazol may be promising as a drug to improve cognitive function in addition to preventing recurrent cerebral infarction.

Through a process of photoelectrochemical (PEC) water splitting, we demonstrated an effective strategy for engineering the barrier height of a heterogeneous semiconductor interface by piezoelectric polarization, known as the piezotronic effect. A consistent enhancement or reduction of photocurrent was observed when tensile or compressive strains were applied to the ZnO anode, respectively. The photocurrent variation is attributed to a changed barrier height at the ZnO/ITO interface, which is a result of the remnant piezoelectric potential across the interface due to a nonideal free charge distribution in the ITO electrode. In our system, ∼1.5 mV barrier height change per 0.1% applied strain was identified, and 0.21% tensile strain yielded a ∼10% improvement of the maximum PEC efficiency. The remnant piezopotential is dictated by the screening length of the materials in contact with piezoelectric component. The difference between this time-independent remnant piezopotential effect and time-dependent piezoelectric effect is also studied in details.

Dye-sensitized solar cells (DSCs) with films (photoelectrodes) of ZnO nanopowders and nanorods were constructed and investigated. Films having different thicknesses were fabricated by an electrophoretic deposition technique (EPD) and sensitized using different concentrations of a N719 dye solution. Adsorption isotherms for this dye were obtained and showed different behaviors depending upon whether the adsorbent was nanopowders or nanorods. The DSCs were characterized by linear sweep voltammetry and electrochemical impedance spectroscopy. The photo-electrochemical performance of these DSCs was measured and cell performance depended on the thickness of films, concentration of dye solution used, and the film structure. The DSC having an electrodeposited film of ZnO nanorods showed a higher efficiency than that containing ZnO nanopowders.

We have investigated a template-free electrophoretic deposition (EPD) process using preformed ZnO nanorods suspended in isopropanol. The preformed ZnO nanorods were synthesized using a solvothermal reaction under different conditions of temperature and time. The length of the resulting ZnO nanorods depended on conditions of synthesis. The powders of ZnO nanorods were then suspended in isopropanol. Electrophoretic mobility of the ZnO nanorods was measured and zeta potential calculated. Thin-films comprised of ZnO nanorods were fabricated on transparent conductive oxide glass using EPD. Resulting ZnO thin-films were smooth and uniform, and film-weight was controlled by changing the voltage that was applied as well as the time of deposition. These thin-films were characterized by X-ray diffraction and scanning electron microscopy methods. To illustrate one application of these electrophoretically deposited materials, the films of both ZnO nanorods and nanopowders were used as photoelectrodes of dye-sensitized solar cells (DSCs) and their performance tested. The DSCs fabricated with a film of ZnO nanorods showed higher efficiency than those of ZnO nanopowders.

ZnO nanorods were obtained by solvothermal reaction using quantum dot precursors suspended in ethanol. The ZnO suspensions were prepared from ethanolic zinc acetate solutions in the presence of lithium hydroxide, and treated by solvothermal synthesis under different reaction temperatures and duration times. Parameters of processing of these nanorods were investigated, including the concentration of precursors and solvothermal temperature. The ZnO nanorod powders were characterized by XRD, SEM, TEM, FT-IR, thermal analysis, and isothermal N2(g) adsorption analyses. Commercially available ZnO nanopowders were studied for comparison. Resulting ZnO nanorod powders were pure ZnO and showed higher surfaces area than commercial ZnO nanopowders. Length and diameter of ZnO nanorods depended on the concentration of precursors and the annealing temperature employed. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

InCliPS (Inba Clinical Pathway for local Stroke network) has been utilized among the hospitals in suburban area at Chiba Prefecture. The organization of transferring the stroke patients from acute to rehabilitation hospitals might be improved by the implementation of this clinical pathway. This regional clinical pathway has been useful not only to compile the information about hospitalized medical records but also to investigate the rehabilitation outcome. Following pathway implementation there have been clinically important, but not statistically significant, allied health assessment and decrease hospitalized periods in convalescent rehabilitation hospitals. It is necessary to cooperate among the acute and convalescent rehabilitation hospitals in order to organize the networks for global stroke medical care through the regional clinical pathway. There, however, have been various difficulties for promoting this network because there have been a lot of regional clinical pathways. It is needed to establish the prefectural common clinical pathway for stroke among the hospital networks to reduce the complicated problems. The prefectural common clinical pathway has just been propelled in the project team consisted of the acute and rehabilitation hospitals and prefectural committee.

To assess the effects of daily power-assisted functional electrical stimulation (FES) home program therapy in chronic stroke.A total of 20 consecutively enrolled stroke patients with spastic upper-extremity impairments1 year after stroke were recruited for this non-blinded randomized controlled trial. Subjects were assigned to control and FES groups and followed for 5 months. The FES group used a power-assisted FES device to induce greater muscle contraction by electrical stimulation in proportion to the integrated electromyography (EMG) signal picked up on surface electrodes. Target muscles were the extensor carpi radialis longus (ECRL) and extensor carpi radialis brevis (ECRB), extensor digitorum communis (EDC), extensor indicis proprius (EIP), and deltoid (Del). Patients underwent 30 approximately 60 min FES sessions at home about 6 days/week. Root mean square (RMS) of ECRL, EDC and Del maximum voluntary EMGs, active range of motion (ROM) of wrist and finger extension and shoulder flexion, modified Ashworth scale (MAS), and clinical tests were investigated before and after FES training.The FES group displayed significantly greater improvements in RMS, active ROM, MAS and functional hand tests, and was able to smoothly perform activities of daily life using the hemiplegic upper extremities.Daily power-assisted FES home program therapy can effectively improve wrist and finger extension and shoulder flexion. Proprioceptional sensory feedback might play an important role in power-assisted FES therapy.

Colloidal quantum dot (CQD) solar cells have attracted tremendous attention mostly due to their wide absorption spectrum window and potentially low processability cost. The ultimate efficiency of CQD solar cells is highly limited by their high trap state density. Here we show that the overall device power conversion efficiency could be improved by employing photonic structures that enhance both charge generation and collection efficiencies. By employing a two-dimensional numerical model, we have calculated the characteristics of patterned CQD solar cells based of a simple grating structure. Our calculation predicts a power conversion efficiency as high as 11.2%, with a short circuit current density of 35.2 mA/cm2, a value nearly 1.5 times larger than the conventional flat design, showing the great potential value of patterned quantum dot solar cells.

Colloidal quantum dot (CQD) solar cells have attracted tremendous attention because of their tunable absorption spectrum window and potentially low processing cost. Recently reported quantum junction solar cells represent a promising approach to building a rectifying photovoltaic device that employs CQD layers on each side of the p-n junction. However, the ultimate efficiency of CQD solar cells is still highly limited by their high trap state density in both p- and n-type CQDs. By modeling photonic structures to enhance the light absorption within the carrier transport length and by ensuring that the carrier generation and collection efficiencies were both augmented, our work shows that overall device current density could be improved. We utilized a two-dimensional numerical model to calculate the characteristics of patterned CQD solar cells based on a simple grating structure. Our calculation predicts a short circuit current density as high as 31 mA/cmsup2/sup, a value nearly 1.5 times larger than that of the conventional flat design, showing the great potential value of patterned quantum junction solar cells.

The effect on spastic hemiparesis of a hybrid therapy consisting of functional electrical stimulation and block therapy was examined.Sixteen consecutively enrolled stroke patients who had spastic upper-extremity impairments more than 1 yr after stroke were recruited for this nonblinded randomized controlled trial. Patients underwent hybrid functional electrical stimulation therapy on their extensor carpi radialis longus and brevis, extensor digitorum communis, and extensor indicis proprius muscles once or twice a week for 4 mos after motor point blocks at the spastic finger flexor muscles. Surface electrodes picked up the electromyography signal and stimulated those muscles in proportion to the integrated electromyography signal obtained by the functional electrical stimulation device. The root mean square of the extensor carpi radialis longus and extensor digitorum communis maximum voluntary electromyography, active range of motion of wrist extension, finger extension, Modified Ashworth Scale, and two clinical tests were examined before and after training.Root mean square, active range of motion, Modified Ashworth Scale, and two clinical tests showed marked improvement in all patients as compared with the control subjects.The hybrid therapy was effective for patients with chronic spastic hemiparesis. Proprioceptional sensory feedback may have an important role in power-assisted functional electrical stimulation therapy.

慢性期の患者では認知機能の新たな改善が期待されないためか, 認知リハは行われない傾向にある。本症例では発症後10年以上が経過しているが, 注意訓練を主体とした認知リハの結果, 認知機能の改善が認められた。症例は1991年12月もやもや病, 脳出血の発症から高次脳機能障害を呈した33歳の女性。認知リハ開始前の初期評価において全般的な知的低下, 記憶力の低下, 注意力低下が認められたため, 段階的に注意賦活訓練, 視覚認知訓練, 代償手段活用訓練を, 1ヵ月に1度の外来訓練に, 家庭で行う課題を併用して実施した。認知リハ後は知的機能, 注意力, 記憶力に改善がみられ, 日常生活でも記憶の代償手段の利用が可能となった。訓練前評価から個々に見合った認知リハ計画を立案し推進することが, 改善に寄与したと思われた。慢性期の患者に対しても, 集約的な認知リハの遂行で高次脳機能の維持や改善が可能であると推察される。

Objective: We examined the time at which loss of functioning motor units occurs on the hemiparetic side, the relationship between that loss and hemiparetic severity, and how long that loss continues. Methods: Sample surface motor unit action potentials (S-MUAPs) were evoked in F-waves. They entirely represent the activity of the relative numbers of different shape S-MUAPs for each abductor pollicis brevis muscle. S-MUAPs from selected population of F-waves were averaged after aligning onset latency. Motor unit number was obtained by dividing the maximum M-potential negative peak amplitude by the averaged S-MUAP one. Results: The motor unit number on the hemiparetic side was significantly lower than that on the unaffected side in stroke patients who had suffered hemiparesis for more than 9 days. This motor unit loss was greater in patients with severe hemiparesis. One year after onset, the chronic stroke patients showed the same motor unit loss on hemiparetic side as they had 3 ‐ 4 months after onset. Conclusions: Motor unit loss on the hemiparetic side is present as early as the second week after onset and is correlated with hemiparesis severity, and this loss continues out to 1 year. This may be due to trans-synaptic degeneration that occurs secondarily to upper motor neuron lesion.

Our understanding of motor learning, neuro-plasticity and functional recovery after the occurrence of brain lesion has grown significantly. New findings in basic neuroscience provided stimuli for research in motor rehabilitation. Electrical stimulation can be applied in a variety of ways to the neurological impairment. Especially, electromyography (EMG) initiated electrical muscle stimulation improves motor dysfunction of the hemiparetic arm and hand. Triggered electrical stimulation is reported to be more effective than non-triggered electrical stimulation in facilitating upper extremity motor recovery. Power-assisted FES induces greater muscle contraction by electrical stimulation in proportion to the voluntary integrated EMG signal picked up. Daily power-assisted FES home program therapy with the novel equipment has been able to improve wrist, finger extension and shoulder flexion effectively. Combined modulation of voluntary movement, proprioceptional sensory feedback and electrical stimulation might play an important role to facilitate impaired sensory-motor integration in power-assisted FES therapy. It is recognized that increased cerebral blood flow in the sensory-motor cortex area on the injured side during power-assisted FES session compared to simple active movement or simple electrical stimulation in a multi-channels Near-infrared spectroscopy (NIRS) study to non-invasively and dynamically measure hemoglobin levels in the brain during functional activity.

To investigate how three-directional molecules behave upon complexation with ferric iron, tripodal 1,3,5-benzene-centered mono-, di- and tritopic iron-chelating ligands {C6H3[CO–(Ahe–(HO)Apr)n–OH]3: 1, n = 1; 2, n = 2; 3, n = 3}, composed of strands containing an –Ahe–(HO)Apr– sequence [Ahe = 6-aminohexanoyl; (HO)Apr = 3-(N-hydroxy)aminopropanoyl], were synthesized. These hydroxamate ligands form intramolecular six-coordinate octahedral complexes with Fe(III): Fe1-1, Fe1-2, Fe2-2, Fe1-3, Fe2-3 and Fe3-3. The complexes formed were investigated from a topological viewpoint and examined in terms of stability against attack by H+ and HO−, monoprotonation equilibrium and iron removal kinetics using a 20-molar excess of EDTA. Fe1-1, Fe1-2 and Fe2-2 have tripodal interstrand structures. In particular, the iron removal reaction of Fe2-2 shows a consecutive first-order reaction pattern. From kinetic data of the first-order reactions, Fe1-3, Fe2-3 and Fe3-3 are concluded to possess one, two and three discrete ferrioxamine-type (intrastrand) structures, respectively.

Combining three units of one of H-(alanyl)n-beta-(HO)alanyl peptides (n = 1-3) with nitrilotriacetic acid affords tripodal peptide hydroxamate ligands (1L, 1D, 2LL, 2DL, and 3LLL, where each L or D denotes the L- or D-alanyl residue). These ligands form six-coordinate octahedral complexes (Fe-1L, Fe-1D, Fe-2LL, Fe-2DL, and Fe-3LLL) with iron(III) in aqueous near neutral pH solution, and the stability and the chirality of the complexes formed depend on the alanyl residues incorporated. Thus Fe-2LL is the most stable against attack of H+ and OH- ions and the least labile in the iron(III) removal by EDTA. The CD spectra show a predominance of the A configuration for Fe-1D, Fe-2LL, Fe-2DL, and Fe-3LLL, but the opposite delta configuration for Fe-1L. These ligands and their gallium(III) complexes are studied by 1H NMR spectroscopy in DMSO-d6 solution. CD and NMR spectral analysis, aided by molecular model examinations, indicates that critical factors in controlling the configuration and the stability of the complexes are (1) the hydroxamate-carrying alanyl residue, (2) the expanse of an interior space in the ligand, and (3) an interstrand amide NH hydrogen bond; the latter bonding is possible with ligands 2LL and 2DL. A microbial growth promotion activity test shows that ligands 1L, 2LL, and 3LLL all act as iron-transporting agents.

Hara Y, Akaboshi K, Masakado Y, Chino N. Physiologic decrease of single thenar motor units in the F-response in stroke patients. Arch Phys Med Rehabil 2000;81:418-23. Objective: To investigate the left-right difference and the reproducibility by the F-wave motor unit number estimation and to compare the motor unit number between the hemiplegic and unaffected side in stroke patients. Setting: A referral center and institutional practice providing outpatient care. Subjects: Seven healthy volunteers and 15 consecutive stroke patients. Design: Diagnostic statistical test and correlational study. Method: Submaximal stimuli were used to evoke a sample of surface motor unit action potentials (S-MUAPs) in the F-waves that are entirely representative of the relative numbers of detected S-MUAPs of different sizes. The average S-MUAP amplitude was calculated from a selected population of F-wave responses for each abductor pollicis brevis (APB) muscle. The motor unit number was calculated by dividing the maximum M-potential negative peak amplitude by the average S-MUAP negative peak amplitude. Result: There was no statistical difference between motor unit numbers on either side and between test and retest in this motor unit number estimation method among normal subjects. The motor unit number on the hemiplegic side was significantly lower than on the unaffected side ( p Conclusion: The motor unit could decrease in the hemiplegic side after a moderate-to-severe hemiplegic stroke and this decrement might be due to the transsynaptic degeneration secondary to an upper motor neuron lesion. © 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Several authors have reported that disuse might not be a major factor of muscle wasting in hemiplegic patients with stroke. A number of published investigations have shown that pathological spontaneous activity can occur in electromyographic studies in upper motor neuron lesions. There have been some reports that the decrease of hemiplegic side M-potential reflects the drop of motor unit numbers. Most of them have estimated that pathological spontaneous activity in hemiplegic muscles might due to transsynaptic degeneration. The submaximal stimuli can evoke a sample of motor unit action potentials of S-MUAPs in the F-response entirely representative of the relative numbers of surface detected S-MUAPs of different sizes. The motor unit number estimation (MUNE) was investigated among the bilateral abductor pollicis brevis (APB) muscles in seven healthy normal controls and fifteen stroke patients with moderate-to-severe hemiplegia. The needle EMG was examined in hemiplegic side APB. The average S-MUAP on each APB muscle was calculated from a selected population of F-wave responses. The MUNE was calculated by dividing the negative peak amplitude measured from the average S-MUAP waveform into corresponding values measured from a maximum M-potential. There was no statistically difference between the both sides motor units number among normal subjects and this MUNE method also revealed the good reproducibility in them. The needle EMG revealed the spontaneous activity in hemiplegic APB muscles at 3-4 months after the onset. The motor unit number on the hemiplegic side was significantly lower than on the unaffected side (p

Fujiwara T, Hara Y, Chino N: Expiratory function in complete tetraplegics: study of spirometry, maximal expiratory pressure, and muscle activity of pectoralis major and latissimus dorsi muscles. Am J Phys Med Rehabil 1999;78:464-469 Respiratory complications, such as pneumonia and atelectasis, are major causes of mortality and inhibit rehabilitation programs in spinal cord injury. Tetraplegic patients cannot cough enough to clear their sputum because of expiratory muscle weakness, mainly of the abdominal muscles. However, tetraplegics are still able to activate some muscles during coughing. Some tetraplegics, even though they cannot contract the abdominal muscles, can cough effectively. It was supposed that some accessory expiratory muscles were activated during coughing in tetraplegics. We, therefore, studied the peak expiratory flow rate, expiratory muscle strength, and the activities of the pectoralis major and latissimus dorsi muscles in 11 complete tetraplegics. Peak expiratory flow rate was measured by spirometry. Expiratory muscles strength was assessed by maximal expiratory mouth pressure; muscle activity was assessed by means of the root mean square voltage obtained by surface electromyography. The results showed that peak expiratory flow rate, maximal expiratory mouth pressure, and root mean square of these two muscles were correlated with neurological level. Peak expiratory flow rate was correlated with peak expiratory flow rate. Peak expiratory flow rate was correlated with the root mean square voltage of the pectoralis major and latissimus dorsi muscles. It was supposed that these two muscles were activated as accessory expiratory muscles and play an important role in expiratory function in tetraplegic patients.

The degree of disability varies widely among C6 tetraplegic patients in comparison with that at other neurological levels. Shoulder muscle strength is thought to be one factor that affects functional outcome. The aim of this study was to examine the relationship between shoulder muscle strength and the Functional Independence Measure (FIM) motor score among 14 complete C6 tetraplegic patients. The FIM motor score and American Spinal Injury Association (ASIA) motor score of these patients were assessed upon discharge. We evaluated muscle strength of bilateral scapular abduction and upward rotation, shoulder vertical adduction and shoulder extension by manual muscle testing (MMT). The total shoulder strength score was calculated from the summation of those six MMT scores. The relationships among ASIA motor score, total shoulder strength score and FIM motor score were analyzed. The total shoulder strength score was significantly correlated with the FIM motor score and the score of the transfer item in the FIM. In the transfer item of the FIM, the total shoulder strength score showed a statistically significant difference between the Independent and Dependent Group. Shoulder muscle strength appears to be an important factor in the functional abilities of those with C6 complete tetraplegia. Functional variation depends on the strength of shoulder muscles, especially among C6 tetraplegics.

WHOが推奨するCraig Handicap Assessment and Reporting Technique (CHART) を用いて脊髄損傷患者を評価し, その社会的不利に影響を与える因子を検討した.対象は外来通院中の完全脊髄損傷患者73名 (頸損30名, 胸腰損43名) で, CHART得点と, ASIA Motor score, FIM運動項目の排尿, 排便コントロール, 褥瘡の既往との関係を調べた.結果はCHARTの得点はASIA Motor scoreとは相関しなかった (p=0.13) が, 排尿, 排便が自立しているほど高得点であった (排尿自立群414.1点, 非自立群337.9点 : p

肩関節拘縮を認めた脳卒中患者11例(肩関節痛8例)において,肩甲下筋モーターポイントブロックの効果を検討した.患側肩甲下筋のモーターポイント数ヵ所に5%フェノール液を数ml注入した後,他動的ROMは屈曲25.6°,外転18.9°,外旋23.9°改善し(p

Hexagonal patterned indium tin oxide (ITO) with a height of 1.5 μm was fabricated on fluorinated SnO2 (FTO) substrate via nanoimprint lithography and pulsed laser deposition (PLD). Tantalum doped TiO2 was deposited on the patterned substrate by PLD. The film of Ta:TiO2 grew vertically and separately on the patterned ITO and formed a brush-like structure. Dye-sensitized solar cells with the Ta:TiO2 film deposited on the patterned substrate as well as flat FTO substrate for comparison were fabricated and tested. The device with the patterned substrate showed a 25% increase in short circuit current (Jsc) compared to the one with flat FTO substrate. Optical and photoelectrochemical characterization techniques were performed to investigate the improvement. The increase of Jsc was attributed to the enhancements of light absorption in the 600–750 nm range and collection of excited electrons by the brush-like structure and the patterned ITO, respectively.

In recent years, our understanding of motor learning, neuroplasticity and functional recovery after the occurrence of brain lesion has grown significantly. New findings in basic neuroscience have provided an impetus for research in motor rehabilitation. Several prospective studies have shown that repeated motor practice and motor activity in a real world environment have a favorable effect on motor recovery in stroke patients. Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following a stroke. In particular, electromyography (EMG)- triggered electrical muscle stimulation improves the motor function of the hemiparetic arm and hand. Triggered electrical stimulation is reported to be more effective than non-triggered electrical stimulation in facilitating upper extremity motor recovery after stroke. EMG-controlled functional electrical stimulation (FES) induces greater muscle contraction by electrical stimulation that is in proportion to voluntary integrated EMG signals. EMG-controlled FES and motor point block for antagonist muscles have been applied as a new hybrid FES therapy in an outpatient rehabilitation clinic for patients with stroke with good result. Daily EMG-controlled FES home-program therapy with novel equipment has been shown to effectively improve wrist, finger extension, and shoulder flexion. Combined modulation of voluntary movement, proprioceptive sensory feedback, and electrical stimulation might play an important role in improving impaired sensory-motor integration by EMG-controlled FES therapy. A multi-channel near-infrared spectroscopy (NIRS) studies in which the hemoglobin levels in the brain were non-invasively and dynamically measured during functional activity found that the cerebral blood flow in the injured sensory-motor cortex area is greater during a EMG-controlled FES session than during simple active movement or simple electrical stimulation. Nevertheless, evidence-based strategies for FES rehabilitation are more and more available, particularly for patients suffering from hemiparesis.

Green tea leaves are rich in polyphenolic compounds known as catechins, which have potent biological anti-oxidant activity. Oxidative stress greatly mediates neuronal and behavioral deficits during aging, and elevated levels of amyloid β peptide (Aβ) levels in the brain increases the levels of oxidative stress, leading to neurodegeneration in the corticohippocampal tissues. We prepared an animal model of Alzheimer’s disease (AD) by infusing Aβ (1–40) in the rat cerebral ventricle. This was associated with impaired spatial cognitive learning ability and increased oxidative stress levels in the brain tissues, and we used it to demonstrate the beneficial effects of green tea catechins on AD. Administration of green tea catechins prevented the impairment with a concomitant decrease in the levels of oxidative stress and enhanced hippocampal neurogenesis. The preventative effects of green tea catechins on cognitive decline with aging and AD pathology are introduced here.

A pair of linear and cyclic peptide-based trihydroxamate ligands (1 and 2) have been prepared through fragment condensation of suitably protected Ala-Ala-β(HO)Ala units. These ligands have an eight...

脳卒中患者の体力評価における上肢エルゴメーター負荷(AE)の有用性を検討する目的で,片麻痺患者87名と健常者35名を比較した.予備実験では負荷の再現性は高く,片側負荷のVO2maxは両側の約80%に相当し,左右差はなかった.VO2maxは両群で差がないのに対し,心拍酸素係数は片麻痺群で有意に低かった.これは末梢性要因(筋)の関与が大きい最大運動においては健側の訓練効果により差が出にくいのに対し,中枢性要因(心肺系)を反映する最大下運動においては体力の低下をとらえやすいためと思われた.さらに測定が容易な握力から体力を推定しうることが示唆された.AEは片麻痺患者の体力を考慮したリハビリテーションを行ううえで有用と考えられた.

Objective The relation was investigated between hemiparetic arm function improvement and brain cortical perfusion (BCP) change during voluntary muscle contraction (VOL), EMG-controlled FES (EMG-FES) and simple electrical muscle stimulation (ES) before and after EMG-FES therapy in chronic stroke patients. Methods Sixteen chronic stroke patients with moderate residual hemiparesis underwent 5months of task-orientated EMG-FES therapy of the paretic arm once or twice a week. Before and after treatment, arm function was clinically evaluated and BCP during VOL, ES and EMG-FES were assessed using multi-channel near-infrared spectroscopy. Results BCP in the ipsilesional sensory-motor cortex (SMC) was greater during EMG-FES than during VOL or ES; therefore, EMG-FES caused a shift in the dominant BCP from the contralesional to ipsilesional SMC. After EMG-FES therapy, arm function improved in most patients, with some individual variability, and there was significant improvement in Fugl–Meyer (FM) score and maximal grip strength (GS). Clinical improvement was accompanied by an increase in ipsilesional SMC activation during VOL and EMG-FES condition. Conclusion The EMG-FES may have more influence on ipsilesional BCP than VOL or ES alone. Significance The sensory motor integration during EMG-FES therapy might facilitate BCP of the ipsilesional SMC and result in functional improvement of hemiparetic upper extremity.

The supplementary motor area (SMA) has been regarded as a third speech area. The SMA is anatomically classified into two regions, pre-SMA and SMA proper, but the functional specialization of speech production between the two regions remains unknown. Although word retrieval difficulties were often observed in older adults, there was no report as to whether the SMA would be involved in the retrieval difficulties. We focused on the SMA as a function of word production and then used near-infrared spectroscopy (NIRS) with the verbal fluency task (VFT) to explore the possible mechanism underlying the retrieval difficulties related to aging. Based on the anatomical differences within the SMA, we relied on region-of-interest (ROI) analysis to compare the brain activation patterns in the SMA during VFT between 11 healthy elder and 11 younger subjects in the situation where both groups show comparable task performance. Notably, the anterior VFT-related SMA response was more robust in the younger than in the elder group. Furthermore, anterior SMA responses in the elder group may only have a positive correlation with the VFT performance. The findings imply that anterior SMA hypoactivity in elders may cause word retrieval difficulties, while bilateral prefrontal cortices, having close connection with the pre-SMA, may contribute to the compensatory process that enables equivalent performance of the elder group with the younger one.

Three-dimensional (3D) nanowire (NW) networks are promising for designing high-performance photoelectrochemical (PEC) electrodes owing to their long optical path for efficient light absorption, high-quality one-dimensional conducting channels for rapid electron-hole separation and charge transportation, as well as high surface areas for fast interfacial charge transfer and electrochemical reactions. By growing titanium dioxide (TiO(2)) nanorods (NRs) uniformly on dense Si NW array backbones, we demonstrated a novel three-dimensional high-density heterogeneous NW architecture that could enhance photoelectrochemical efficiency. A 3D NW architecture consisting of 20 μm long wet-etched Si NWs and dense TiO(2) NRs yielded a photoelectrochemical efficiency of 2.1%, which is three times higher than that of TiO(2) film-Si NWs having a core-shell structure. This result suggests that the 3D NW architecture is superior to straight NW arrays for PEC electrode design. The efficiency could be further improved by optimizing the number of overcoating cycles and the length/density of NW backbones. By implementing these 3D NW networks into electrode design, one may be able to advantageously impact PEC and photovoltaic device performance.

Our understanding of motor learning, neuroplasticity, and functional recovery after the occurrence of brain lesions has increased considerably. New findings in basic neuroscience have provided an impetus for research in motor rehabilitation. Several prospective studies have shown that repeated motor practice and motor activity in a real world environment have a favorable effect on motor recovery in stroke patients. Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following a stroke. In particular, electromyography (EMG)-triggered electrical muscle stimulation improves the motor function of the hemiparetic arm and hand. Triggered electrical stimulation is reported to be more effective than non-triggered electrical stimulation in facilitating upper extremity motor recovery after stroke. Power-assisted functional electrical stimulation (FES) induces greater muscle contraction by electrical stimulation that is in proportion to voluntary integrated EMG signals. Daily power-assisted FES home-program therapy with novel equipment has been shown to effectively improve wrist, finger extension, and shoulder flexion. Combined modulation of voluntary movement, proprioceptive sensory feedback, and electrical stimulation might play an important role in improving impaired sensory-motor integration by power-assisted FES therapy. A multi-channel near-infrared spectroscopy (NIRS) studies in which the hemoglobin levels in the brain were non-invasively and dynamically measured during functional activity found that the cerebral blood flow in the injured sensory-motor cortex area is greater during a power-assisted FES session than during simple active movement or simple electrical stimulation. A novel power-assisted FES sleeve (Cyberhand) has been developed for the rehabilitation of hemiplegic upper extremities.

In recent years, our understanding of motor learning, neuroplasticity, and functional recovery after the occurrence of brain lesion has grown significantly. New findings in basic neuroscience have stimulated research in motor rehabilitation. Repeated motor practice and motor activity in a real-world environment have been identified in several prospective studies as favorable for motor recovery in stroke patients. Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following stroke. In this paper, an overview of current research into clinical and therapeutic applications of functional electrical stimulation (FES) is presented. In particular, electromyography (EMG)-initiated electrical muscle stimulation--but not electrical muscle stimulation alone--improves the motor function of the hemiparetic arm and hand. Triggered electrical stimulation is reported to be more effective than untriggered electrical stimulation in facilitating upper extremity motor recovery following stroke. Power-assisted FES induces greater muscle contraction by electrical stimulation in proportion to the voluntary integrated EMG signal picked up, which is regulated by a closed-loop control system. Power-assisted FES and motor point block for antagonist muscles have been applied with good results as a new hybrid FES therapy in an outpatient rehabilitation clinic for patients with stroke. Furthermore, a daily home program therapy with power-assisted FES using new equipment has been able to effectively improve wrist and finger extension and shoulder flexion. Proprioceptive sensory feedback might play an important role in power-assisted FES therapy. Although many physiotherapeutic modalities have been established, conclusive proof of their benefit and physiological models of their effects on neuronal structures and processes are still missing. A multichannel near-infrared spectroscopy study to noninvasively and dynamically measure hemoglobin levels in the brain during functional activity has shown that cerebral blood flow in the sensory-motor cortex on the injured side is higher during a power-assisted FES session than during simple active movement or simple electrical stimulation. Nevertheless, evidence-based strategies for motor rehabilitation are more easily available, particularly for patients with hemiparesis.