Evaluation of a gate capacitance in the sub-aF range for a chemical field-effect transistor with a silicon nanowire channel

An evaluation of the gate capacitance of a field-effect transitor (FET) whose channel length and width are several ten nanometer, is a key point for sensors applications. However, experimental and precise evaluation of capacitance in the aF range or less has been extremely difficult. Here, we report an extraction of the capacitance down to 0.55 aF for a silicon FET with a nanoscale wire channel whose width and length are 15 and 50 nm, respectively. The extraction can be achieved by using a combination of four kinds of measurements: current characteristics modulated by double gates, random-telegraph-signal noise induced by trapping and detrapping of a single electron, dielectric polarization noise, and current characteristics showing Coulomb blockade at low temperature. The extraction of such a small gate capacitance enables us to evaluate electron mobility in a nanoscale wire using a classical model of current characteristics of a FET.Comment: To be published in IEEE Trans. Nanotechno

Valley splitting by extended zone effective mass approximation incorporating strain in silicon

Silicon metal-oxide-semiconductor field effect transistors (MOSFETs) fabricated on a SIMOX (001) substrate, which is a kind of silicon on insulator (SOI) substrate, that is annealed at high temperature for a long time are known to exhibit large valley splitting, but the origin of this splitting has long been unknown. Extended zone effective-mass approximation (EMA) predicts that strain significantly affects valley splitting. In this study, we analyzed valley splitting based on this theory and found that the shear strain along of approximately 5% near the buried oxide (BOX) interface is a promising source for large valley splitting.Comment: 12 pages, 5 figures

Percutaneous Endoscopic Gastrostomy, Duodenostomy and Jejunostomy

Although enteral feeding by nasal gastric tube is popular for the patients who have a swallowing disability and require long-term nutritional support, but have intact gut, this tube sometimes causes aspiration pneumonia or esophageal ulcer. For these patients, conventional techniques for performance of a feeding gastrostomy made by surgical laparotomy have been used so far. However, these patients are frequently poor anesthetic and operative risks. Percutaneous endoscopic gastrostomy (PEG) which can be accomplished with local anesthesia and without the necessity for laparotomy has become popular in the clinical treatment for these patients. PEG was performed in 31 cases, percutaneous endoscopic duodenostomy (PED) in 1 case, and percutaneous endoscopic jejunostomy (PEJ) in 2 cases. All patients were successfully placed, and no major complication and few minor complications (9%) were experienced in this procedure. After this procedure, some patients could discharge their sputa easily and their pneumonia subsided. PED and PEJ for the patients who had previously received gastrostomy could also be done successfully with great care. Our experience suggests that PEG, PED, and PEJ are rapid, safe, and useful procedures for the patients who have poor anesthetic or poor operative risks

MEFV gene mutations in neuro-Behçet's disease and neuro-Sweet disease

ArticleAnnals of clinical and translational neurology. 6(12): 2595-2600 (2019)journal articl

がん地域連携における役割分担に関するアンケート調査

It was suggested long ago that regional cooperation is necessary for cancer patients. Both doctors in base hospitals and community doctors understand the importance of such cooperation. Here we report the results of our widely distributed questionnaire designed to clarify the division of physicians' roles and to strengthen the relationships between base hospital and community doctors. The questionnaire asks whether community doctors can accept cancer patients and what types of medical treatment the doctors can provide for patients with esophageal cancer, lung cancer, breast cancer, and thyroid cancer. The doctors in 289 of 550 (53%) facilities completed and returned the questionnaire. About half of the community doctors responded that they can accept patients with any of the four cancers and can provide most types of the necessary medical examinations and treatments in their daily practices. Most of the community doctors indicated that they could not provide some anti-cancer drugs and supportive drug therapies for breast cancer patients. The development and implementation of a clinical pathway system could enable the participation of more community doctors and base hospital doctors. Although our findings are preliminary, they will contribute to a foundation for building better regional corporative relationships with community doctors who treat cancer patients