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Phase Transforming Cellular Material (PXCM) exhibits transformation by loading and maintains the deformed shape even after unloading after compression and restores the original shape by deforming in the opposite direction. Conventional PXCM needs to be stressed reversely to restore its original shape. Bimetals, i.e., clad sheets of metals with large differences in the coefficient of thermal expansion, can spontaneously bend in response to temperature changes because of thermal stress. In this study, we designed a lattice structure that not only deforms when a compressive/tensile load is applied but also changes its shape by heating/cooling by using bimetal for the curved beam of PXCM. A newly created PXCM is named thermally induced PXCM. The TI-PXCM exhibited a large recovery strain of 20% or more with a temperature hysteresis of 302 K in the temperature range of − 190 to 200 °C. Graphical abstract

A number of disease conditions in luminal organs are associated with alterations in tissue mechanical properties. Here, we report a new omni-directional viewing Laser Speckle Rheology (LSR) catheter for mapping the mechanical properties of luminal organs without the need for rotational motion. The LSR catheter incorporates multiple illumination fibers, an optical fiber bundle and a multi-faceted mirror to permit omni-directional viewing of the luminal wall. By retracting the catheter using a motor-drive assembly, cylindrical maps of tissue mechanical properties are reconstructed. Evaluation conducted in a test phantom with circumferentially-varying mechanical properties demonstrates the capability of the LSR catheter for the accurate mechanical assessment of luminal organs.

A number of disease conditions including coronary atherosclerosis, peripheral artery disease and gastro-intestinal malignancies are associated with alterations in tissue mechanical properties. Laser speckle rheology (LSR) has been demonstrated to provide important information on tissue mechanical properties by analyzing the time scale of temporal speckle intensity fluctuations, which serves as an index of tissue viscoelasticity. In order to measure the mechanical properties of luminal organs in vivo, LSR must be conducted via a miniature endoscope or catheter. Here we demonstrate the capability of an omni-directional LSR catheter to quantify tissue mechanical properties over the entire luminal circumference without the need for rotational motion. Retracting the catheter using a motor-drive assembly enables the reconstruction of cylindrical maps of tissue mechanical properties. The performance of the LSR catheter is tested using a luminal phantom with mechanical moduli that vary in both circumferential and longitudinal directions. 2D cylindrical maps of phantom viscoelastic properties are reconstructed over four quadrants of the coronary circumference simultaneously during catheter pullback. The reconstructed cylindrical maps of the decorrelation time constants easily distinguish the different gel components of the phantom with different viscoelastic moduli. The average values of decorrelation times calculated for each gel component of the phantom show a strong correspondence with the viscoelastic moduli measured via standard mechanical rheometry. These results highlight the capability for cylindrical mapping of tissue viscoelastic properties using LSR in luminal organs using a miniature catheter, thus opening the opportunity for improved diagnosis of several disease conditions.

Acute myocardial infarction is frequently caused by the rupture of coronary plaques with severely compromised viscoelastic properties. We have developed a new optical technology termed intravascular laser speckle imaging (ILSI) that evaluates plaque viscoelastic properties, by measuring the time scale (time constant, τ) of temporally evolving laser speckle fluctuations. To enable coronary evaluation in vivo, an optical ILSI catheter has been developed that accomplishes omni-directional illumination and viewing of the entire coronary circumference without the need for mechanical rotation. Here, we describe the capability of ILSI for evaluating human coronary atherosclerosis in cadaveric hearts. ILSI was conducted in conjunction with optical coherence tomography (OCT) imaging in five human cadaveric hearts. The left coronary artery (LCA), left anterior descending (LAD), left circumflex artery (LCx), and right coronary artery (RCA) segments were resected and secured on custom-developed coronary holders to enable accurate co-registration between ILSI, OCT, and histopathology. Speckle time constants, τ, calculated from each ILSI section were compared with lipid and collagen content measured from quantitative Histopathological analysis of the corresponding Oil Red O and Picrosirius Red stained sections. Because the presence of low viscosity lipid elicits rapid speckle fluctuations, we observed an inverse correlation between τ measured by ILSI and lipid content (R= -0.64, p< 0.05). In contrast, the higher viscoelastic modulus of fibrous regions resulted in a positive correlation between τ and collagen content (R= 0.54, p< 0.05). These results demonstrate the feasibility of conducting ILSI evaluation of arterial mechanical properties using a miniaturized omni-directional catheter.

Dynamic individual beam control in a multi-electron-beam system was demonstrated. In a multi-beam system, individual beam blanking and accurate correction of each beam position and irradiation dose are essential. In this paper, 16 beams in a 1024-beam system were individually blanked at 100-MHz frequency. Individual beam blanking was verified by pattern delineation. The beam position was corrected by the data shift through the feedback from the positions of formerly delineated patterns. The irradiation dose was corrected by measuring the dose of each beam and calibrating the irradiation time. Moreover, a movable blanking aperture was installed to improve the uniformity of blanking control. Finally, these corrections were evaluated by measuring the line widths in delineated patterns smaller than 65 nm. As a result, positioning accuracy within 1 pixel and dose deviation within 2.4% were achieved. In conclusion, it was clarified that our multi-beam-system has potential applications in

L10-ordered MnAl thin films were epitaxially grown by sputtering. The film composition dependences of structural and magnetic properties were systematically investigated in the MnAl thin films. Both the L10-ordered parameter and the perpendicular magnetic anisotropy energy strongly depended on the composition of the MnAl thin films. The MnAl thin films with a Mn composition of 53–54 at. % showed both the highest L10-ordered parameter and the perpendicular magnetic anisotropy. The substrate and annealing temperatures were optimized to improve the magnetic properties and surface morphology. We have fabricated MnAl thin films with both a very high K u of 12 × 106 erg/cm3 and a small surface roughness of ca. 0.2 nm by optimizing the film composition and substrate and annealing temperatures. These results are useful guidelines for the fabrication of highly L10-ordered MnAl thin films with a large perpendicular magnetic anisotropy.

By chemical vapor deposition, we have tried to grow epitaxial films of graphene nano-ribbons on Pt (755) and TiC (755) surfaces. Some properties of these graphene films have been clarified by X-ray photoelectron spectroscopy, low energy electron diffraction, and angle-resolved ultraviolet photoelectron spectroscopy. Nano-ribbons have not been prepared on Pt (755), but they have successfully been prepared on TiC (755). Quantized n bands and new electronic states at E, have been found in the photoemission spectra.

Structural and magnetic properties of MnAl thin films with different composition, growth temperature, and post-annealing temperature were investigated. The optimum condition for fabrication of L10-MnAl perpendicularly magnetized thin film deposited on Cr-buffered MgO single crystal substrate was revealed. The results of x ray diffraction indicated that the MnAl films annealed at proper temperature had a (001)-orientation and L10-ordered structure. The L10-ordered films were perpendicularly magnetized and had a large perpendicular anisotropy. In addition, low surface roughness was achieved. For the optimized fabrication condition, the saturation magnetization Ms of 600 emu/cm3 and perpendicular magnetic anisotropy Ku of 1.0 × 107 erg/cm3 was obtained using the Mn48Al52 target at deposition temperature of 200 °C and post-annealing temperature of 450 °C.

A novel single-column multi-electron-beam system, called a beam-split array, has been developed for a high-resolution, high-throughput lithography tool. In this system, a single electron beam is divided into 1024 beams by a multisource module (MSM) composed of an aperture array (a beam-dividing aperture), a static lens array (Einzel lenses for each divided beam), and a blanker array (BLA, blanking electrode pairs for each focused beam). The MSM is used to form multiple intermediate images of the electron source at the BLA. These images are demagnified to form final images through a projection optics consisting of a double lens doublet with a blanking aperture and deflector. To align the multiple beam paths in the MSM, aligners between these arrays are used, and the aligner conditions are determined by monitoring the blanking-aperture image. Moreover, because each beam current is about 0.1% of the total beam current on the specimen, a high-contrast transmission detection method is used to detect the electr...

A testing apparatus for inspecting the beams formed by a multisource module (MSM) was built for the feasibility study of a beam splitting array (BSA), a multielectron beam system the authors are developing. In this BSA, the MSM plays the following three key roles: splitting the beam from a single cathode into 32×32 beams, converging the 32×32 beams, and blanking them individually. Accordingly, the inspection of all beams formed by the MSM is essential for the feasibility study of the system. The testing apparatus was therefore designed for measuring all the beams formed by the MSM without demagnifying them. To maintain the accuracy during the inspection of all 32×32 beams, the measurement process was automated. This testing apparatus was used to measure the diameters and misalignments of all beams formed by a prototype MSM. As a result, the mean values of the transverse and the longitudinal diameters were found to be 0.88 and 0.92μm, respectively. A single stigmator can cancel the difference between these...