Showing papers by "Osamu Sato published in 2022"

Photoinduced Persistent Polarization Change in a Spin Transition Crystal.

Abstract: Using light as a local heat source to induce a temporary pyroelectric current is widely recognized as an effective way to control the polarization of crystalline materials. In contrast, harnessing light directly to modulate the polarization of a crystal via excitation of the electronic bands remains less explored. In this study, we report an Fe(II) spin crossover crystal that exhibits photoinduced macroscopic polarization change upon excitation by green light. When the excited crystal relaxes to the ground state, the corresponding pyroelectric current can be detected. An analysis of the structures, magnetic properties and the Mössbauer and infrared spectra of the complex, supported by calculations, revealed that the polarization change is dictated by the directional relative movement of ions during the spin transition process. The spin transition and polarization change occur simultaneously in response to light stimulus, which demonstrates the enormous potential of polar spin crossover systems in the field of optoelectronic materials.

Turnover in Japanese IT Professionals: Antecendants and Nuances

Abstract: The Japanese information technology (IT) workplace is unique compared to that of other nations. IT represents a large sector of the country’s economy, and organizations need to develop proactive approaches to retain their IT workforce. In order to manage employee turnover, they need to understand the distinctive factors influencing employee turnover intention, as turnover intention is known to be a reliable predictor of actual turnover. In this study, a model was constructed and tested with data collected from 284 Japanese IT professionals. Our findings show that the effects of work exhaustion, personal accomplishment, and friendship networks on turnover intention are fully mediated through job satisfaction. Work-home conflict has no impact on job satisfaction. The strength of the relationships is stronger for younger than for older organizations. Furthermore, individualistic factors (i.e., work exhaustion and personal accomplishment) have a stronger impact on job satisfaction than collectivistic factors (i.e., work-home conflict and friendship networks). These results show the fragility of the notion of long-term employment, which is supposed to be embraced within the entire Japanese work culture.

Macroscopic Polarization Change of Mononuclear Valence Tautomeric Cobalt Complexes Through the Use of Enantiopure Ligand.

Abstract: The crystallization of a complex having electron transfer properties in a polar space group can induce the polarization switching of a crystal in a specific direction, which is attractive for the development of sensors, memory devices, and capacitors. Unfortunately, the probability of crystallization in a polar space group is usually low. Noticing that enantiopure compounds crystallize in Sohncke space groups, this paper reports a strategy for the molecular design of non-ferroelectric polarization switching crystals based on the use of intramolecular electron transfer and chirality. In addition, this paper describes the synthesis of a mononuclear valence tautomeric (VT) cobalt complex bearing an enantiopure ligand. The introduction of enantiomer enables the crystallization of the complex in the polar space group (P2 1 ). The polarization of the crystals along the b-axis direction is not canceled out and the VT transition is accompanied by a change in the macroscopic polarization of the polar crystal. Polarization switching via electron transfer is realized at around room temperature.

Long-Term Outcomes following Common Femoral Endarterectomy

Abstract: Thromboendarterectomy of the common femoral artery (CFA) for occlusive disease is a crucial procedure in vascular surgery. As an outcome reference for emerging endovascular procedures and new devices, we need more robust evidence of the outcome of this gold standard technique. The purpose of this study was to report 10-year results after femoral endarterectomy (FEA). A retrospective review of medical records at our institution identified eighty consecutive patients (91 limbs) who underwent FEA for CFA lesions. Indications for FEA included 50 limbs (55%) for intermittent claudication (IC) and 39 limbs (43%) with chronic limb-threatening ischemia (CLTI). Two limbs (2%) underwent FEA to prevent hemodynamic steal during extra-anatomical bypass. Adjunctive procedures included endovascular therapy in 32%. CFAs were closed with patch angioplasty in 44%. With a mean follow-up period of 39 months, the survival rates at 3 and 8 years were 85% and 77%, respectively. Limb salvage rates were 92% and 87%. Primary patencies were 98% and 84%. Freedom from target lesion revascularization was 95% at 3 years and 91% at 8 years. Our findings support the durability of FEA, with comparable long-term procedural results in CLTI patients as well as IC patients. Since the FEA is a gate maneuver for hybrid revascularization in CLTI patients, our findings support a strategy combining open and endovascular approaches. Femoral endarterectomy remains a durable solution for common femoral occlusive disease in IC and CLTI in the era of endovascular therapy.

Development of a novel gauge filled with resin for X-ray CT

Abstract: X-ray computed tomography (CT) systems have been widely used for three-dimensional (3D) measurements in the engineering field. Therefore, verifying X-ray CT systems with full traceability is necessary to ensure accurate measurements. Measurement errors of X-ray CT systems are evaluated using a reference gauge whose geometry is calibrated using 3D measuring systems with higher accuracy. Thus, this study developed and characterized a novel reference gauge for X-ray CT systems, comprising spheres embedded in a cylindrical resin.