Syntheses of Spinon Thermal Conductivity Materials in Sr–Cu–O System by Glass‐Ceramics Technique

We have synthesized spinon thermal conductivity materials in Sr–Cu–O system by glass‐ceramics technique. The materials are promising for active control of thermal energy in microelectronic devices because of high and anisotropic thermal conduction, its controllability, and electric insulation. Nevertheless, research on these materials has been limited to that concerning theoretical perspectives and investigation of physical properties using large single crystals. In this study, we adopt glass‐ceramics technique to synthesize these materials: We prepared melt‐quenched multicomponent oxides including SrO and CuO, and checked its glass‐forming ability and crystallization behaviors by heating. As a result, we have found that SrCuO₂ and Sr₁₄Cu₂₄O₄₁, known as the spinon thermal conductivity materials, are synthesized using SrO–CuO–?Li₂O–?Al₂O₃?–Ga₂O₃ system. This synthesis process for the system will provide practical application of the spinon thermal conductivity materials.     

Cerebral Hyperperfusion after Revascularization Inhibits Development of Cerebral Ischemic Lesions Due to Artery-to-Artery Emboli during Carotid Exposure in Endarterectomy for Patients with Preoperative Cerebral Hemodynamic Insufficiency: Revisiting the “Impaired Clearance of Emboli” Concept

The purpose of the present study was to determine whether cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during exposure of the carotid arteries in carotid endarterectomy (CEA). In patients undergoing CEA for internal carotid artery stenosis (≥70%), cerebral blood flow (CBF) was measured using single-photon emission computed tomography (SPECT) before and immediately after CEA. Microembolic signals (MES) were identified using transcranial Doppler during carotid exposure. Diffusion-weighted magnetic resonance imaging (DWI) was performed within 24 h after surgery. Of 32 patients with a combination of reduced cerebrovascular reactivity to acetazolamide on preoperative brain perfusion SPECT and MES during carotid exposure, 14 (44%) showed cerebral hyperperfusion (defined as postoperative CBF increase ≥100% compared with preoperative values), and 16 (50%) developed DWI-characterized postoperative cerebral ischemic lesions. Postoperative cerebral hyperperfusion was significantly associated with the absence of DWI-characterized postoperative cerebral ischemic lesions (95% confidence interval, 0.001–0.179; p = 0.0009). These data suggest that cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during carotid exposure in CEA, supporting the “impaired clearance of emboli” concept. Blood pressure elevation following carotid declamping would be effective when embolism not accompanied by cerebral hyperperfusion occurs during CEA.     

Combination of cytomegalovirus enhancer with human cellular promoters for gene-induced chondrogenesis of human bone marrow mesenchymal stem cells

High-expression plasmid vectors for human mesenchymal stem cells (MSCs) were constructed by combination of cytomegalovirus immediate-early enhancer with cellular promoters. MSCs transfected with the vector showed higher transgene production of a cytokine, which increased the differentiation level to chondrocytes.     

Proposal for a benchmark model of a laminated iron core and a large‐scale and highly accurate magnetic analysis

This paper describes a benchmark model proposed for the clarification of the characteristic of various methods for modeling the laminated iron core. In order to obtain a reference solution of the benchmark model, a large‐scale nonlinear magnetostatic field analysis with a mesh fine enough to represent the microscopic structure of the laminated iron core is carried out by using the hybrid finite element–boundary element (FE‐BE) method combined with the fast multipole method (FMM) based on diagonal forms for translation operators. The computational costs and accuracy of two kinds of homogenization methods are discussed, comparing them with the reference solution. As a consequence, it is verified that the homogenization methods can analyze magnetic fields in laminated iron core within acceptable computational costs. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(1): 26–35, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20809     

Development of rapid hygrothermal pasteurization using saturated water vapor

We developed a novel rapid hygrothermal pasteurization (RHP) method using saturated water vapor with a dew point of 100 °C. In the present study, the effects of RHP on microbiological quality and quality attributes such as color changes, firmness and ascorbic acid content on many fresh-cut fruits and vegetables (cabbage, cucumber, carrot, cherry tomato, bell pepper, strawberry, pineapple and melon) were investigated. The RHP was performed within a second by free-falling samples through a cylindrical processing chamber filled with steam. The RHP resulted in a 0.7–2.0 log order reduction in the numbers of naturally inoculated mesophilic bacteria. Furthermore, the RHP induced no significant changes in color and firmness of samples, except on the leafy vegetable, cabbage. Ascorbic acid was also retained approximately 80% and above. These results indicate that the RHP is a clean and effective method for decontaminating mesophilic bacteria on fresh fruits and vegetables with minimal changes in quality.Industrial relevanceIn fresh-cut industry, an effective and risk-free decontamination technology is required for use in place of a conventional method, washing by chlorine that can produce carcinogenic chlorinated by-products. In this study, the rapid hygrothermal pasteurization (RHP) method using saturated water vapor was invented and their ability for applying minimal processing was evaluated. The results showed that RHP, without using chemicals, can reduce microorganism load and preserve quality attributes in many kinds of fresh-cut fruits and vegetables. Therefore, RHP could be used as a novel method, which can be generally applicable to fresh-cut fruits and vegetables in the food industry.     

Single-Electron Device With Si Nanodot Array and Multiple Input Gates

We have developed a flexible-logic-gate single-electron device (SED) with an array of nanodots. Although the small size of SEDs is highly advantageous, the size of the nanodots inevitably fluctuates, which causes variations in device characteristics. This variability can be eliminated and high device functionality can be obtained by exploiting the oscillatory characteristics and multigate capability of SEDs. We fabricated, on a silicon-on-insulator wafer, a Si nanodot array device with two input gates and a control gate and investigated its basic operation characteristics experimentally. The device was demonstrated to operate as a logic gate providing six important logic functions ( and, or, nand, nor, xor, and xnor), which are obtained by adjusting the control-gate voltage.     

Thermodynamics of iron oxide in Fe x O-dilute CaO + Al2O3 + MgO + Fe x O slags at 1873 K

In order to determine the ferrous and ferric ion capacities: 3

128 line photonic switching system using LiNbO3 switchmatrices and semiconductor traveling wave amplifiers

The possibility of a 128-line photonic space division switching system incorporating LiNbO₃ switch matrices and semiconductor traveling wave amplifiers (TWAs) is discussed. System design is considered in terms of the most suitable location for the TWA devices that gives the most practical power margin. Design requirements for a 128-line photonic switching system suitable for a small-sized private branch exchange requirement are presented along with experimental results. It has been shown that a five-stage switch cascade, suitable for such a high-capacity switching system with a power margin of greater than 5 dB in the highest switch loss situation is possible, using low-facet-reflection TWAs. Such TWA devices have been developed in the 1.3-μm wavelength region with maximum fiber-to-fiber gain values of 15 dB. With maximum gain-polarization dependencies of 3 dB, switch losses can be compensated even under TM mode operation