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Objective: The aim of this study was to examine whether the plantar flexion test could adequately replace treadmill testing in patients who were unable to exercise. Design: Prospective observational study. Patients: Twenty-seven patients with intermittent claudication secondary to peripheral arterial disease (PAD). Methods: Patients performed two treadmill tests and two plantar flexion tests. Ankle pressure, near infrared spectroscopy (NIRS) data, heart rate and blood pressures were monitored along with pain-free and maximum walking distances for treadmill, pain-free and maximum exercise time for plantar flexion. Results: Maximum exercise time and walking distance were well correlated (R=0.74). Eleven patients (41%) developed non-claudicating symptoms during the treadmill test but not during the flexion test. Rate pressure product was significantly higher after the treadmill but not after the plantar flexion. Conclusions: Plantar flexion test showed good reliability and correlation. Plantar flexion may serve as an alternative to treadmill testing in evaluating muscle pain in patients with intermittent claudication. [Copyright &y& Elsevier]

• The numerical stress solutions at incipient failure everywhere, for conical sand heaps under both active and passive conditions were successfully solved. • The 5th order adaptive Runge–Kutta method in conjunction with appropriate numerical perturbations and the shooting technique were employed. • The arching effect in an axisymmetric cone was visualized by the trajectories of principal stresses subjected to various repose angles. Stress discontinuity plays an important role in both planar and conical heaps of granular materials. The aim of this study is to reveal the numerical solutions for the stress distribution in fully plastic conical sand heaps that obey the Mohr-Coulomb yield criterion under both passive and active conditions. Levy's circumferential stress assumption was added to the system of equilibrium equations to formulate a pair of ordinary differential equations that were integrated by the 5th order adaptive Runge–Kutta method. Moreover, the numerical perturbations of the initial conditions were put in place to overcome the singularities of the integrations. Trial-and-error iterations were implemented under the passive condition to indicate the location of the stress discontinuity in conjunction with the application of the stress jump condition. Meanwhile, the shooting technique was employed to facilitate the integration under the active condition. The results of the passive conical sand heaps exhibit a local minimum pressure at the center, thus initiating arch action. In addition, the trajectories of principal stresses visually elucidate the mechanisms of load transfer in the conical sand heaps. The linear-fitting relationship between the location of the stress discontinuity and the repose angle in a conical sand heap under the passive condition was also elaborated. [ABSTRACT FROM AUTHOR]

Abstract: Preparation of epitaxial YBa2Cu3O7 (YBCO) films on cerium oxide-buffered sapphire (r-cut α-Al2O3) substrates by an excimer-laser-assisted metalorganic deposition (ELAMOD) is reported. The ELAMOD process has been developed to bring about the advantage of shorter heating time than that in the conventional metalorganic deposition; the coated films are irradiated by an excimer laser beam before firing. We initiated the ELAMOD–YBCO process using a homogenized 8-mm-square laser beam which irradiates the coated surface in a fixed substrate mode. In order to extend the process applicable to large-area films, a scan irradiation mode was employed and a high critical-current density over 6MA/cm2 has been observed. In the process, an appropriate choice of laser energy is difficult but crucial to obtain YBCO films with high superconducting properties. Then, laser irradiation from backside of the substrate was examined and proved to be beneficial to extend the experimental window of the laser energy. Moreover, a newly developed ELAMOD process using a 90-mm-wide line-beam is also reported which has a potential ability for large-area applications. [Copyright &y& Elsevier]

Abstract: Brain histaminergic neurons play a prominent role in arousal and maintenance of wakefulness (W). H3-receptors control the activity of histaminergic neurons through presynaptic autoinhibition. The role of H3-receptor antagonists/inverse agonists (H3R-antagonists) in the potential therapy of vigilance deficiency and sleep–wake disorders were studied by assessing their effects on the mouse cortical EEG and sleep–wake cycle in comparison to modafinil and classical psychostimulants. The H3R-antagonists, thioperamide and ciproxifan increased W and cortical EEG fast rhythms and, like modafinil, but unlike amphetamine and caffeine, their waking effects were not accompanied by sleep rebound. Conversely, imetit (H3R-agonist) enhanced slow wave sleep and dose-dependently attenuated ciproxifan-induced W, indicating that the effects of both ligands involve H3-receptor mechanisms. Additional studies using knockout (KO) mice confirmed the essential role of H3-receptors and histamine-mediated transmission in the wake properties of H3R-antagonists. Thus ciproxifan produced no increase in W in either histidine-decarboxylase (HDC, histamine-synthesizing enzyme) or H1- or H3-receptor KO-mice whereas its waking effects persisted in H2-receptor KO-mice. These data validate the hypothesis that H3R-antagonists, through disinhibition of H3-autoreceptors, enhancing synaptic histamine that in turn activates postsynaptic H1-receptors promoting W. Interestingly amphetamine and modafinil, despite their potent arousal effects, appear unlikely to depend on histaminergic mechanism as their effects still occurred in HDC KO-mice. The present study thus distinguishes two classes of wake-improving agents: the first acting through non-histaminergic mechanisms and the second acting via histamine and supports brain H3-receptors as potentially novel therapeutic targets for vigilance and sleep–wake disorders. [Copyright &y& Elsevier]

Abstract: Epitaxial YBa2Cu3O7 (YBCO) films with high-critical-current density (J c) properties were successfully prepared on cerium oxide-buffered sapphire (r-cut α-Al2O3) substrates by an excimer-laser-assisted metalorganic deposition (ELAMOD) using a new irradiation manner. The previously reported ELAMOD process in which the laser beam is irradiated from the surface of the substrate has brought about the advantages of shorter heating time as well as high-J c of the YBCO films [M. Sohma, T. Tsuchiya, K. Tsukada, I. Yamaguchi, T. Manabe, T. Kumagai, K. Koyanagi, T. Ebisawa, H. Ohtsu, IEEE Trans. Appl. Supercond. 15 (2007) 3612; M. Sohma, T. Tsuchiya, K. Tsukada, I. Yamaguchi, T. Manabe, T. Kumagai, K. Koyanagi, T. Ebisawa, H. Ohtsu, Physica C 463–465 (2007) 891]. The J c values over 6MA/cm2 has been reported by an inductive method at 77.3K only for the laser-irradiated areas. An awaiting solution has remained since the appropriate fluence range of the laser beam is much limited to obtain high-J c ELAMOD–YBCO films with good reproducibility. In this paper we report a new irradiation manner to resolve the difficulty. The backside of the substrate was irradiated by homogenized KrF excimer laser beam (scanning mode) after application of a fluorine-free ingredient solution. The indispensable laser fluence increased to obtain the high-J c YBCO films because of absorption from the substrate and the CeO2 buffer. High-J c values of around 6MA/cm2 at 77.3K using an inductive method were obtained in the area irradiated at a wider fluence range, while a part of unirradiated area also showed relatively high-J c of 2–5MA/cm2. Attenuation and scattering effects are considered to bring the extended option of the laser fluence. [Copyright &y& Elsevier]