Numerical analysis of voltage-controlled magnetization switching operation in magnetic-topological-insulator-based devices

We theoretically investigate influences of electronic circuit delay, noise and temperature on write-error-rate (WER) in voltage-controlled magnetization switching operation of a magnetic-topological-insulator-based (MTI) device by means of the micromagnetic simulation. This device realizes magnetization switching via spin-orbit torque(SOT) and voltage-controlled magnetic anisotropy (VCMA) which originate from 2D-Dirac electronic structure. We reveal that the device operation is extremely robust against circuit delay and signal-to-noise ratio. We demonstrate that the WER on the order of approximately $10^{-4}$ or below is achieved around room temperature due to steep change in VCMA. Also, we show that the larger SOT improves thermal stability factor. This study provides a next perspective for developing voltage-driven spintronic devices with ultra-low power consumption.Comment: 6 pages, 5 figure

Numerical analysis of perpendicular magnetic printing for hard disks beyond 2 Tb/in2

AbstractA micromagnetic analysis of magnetic printing onto an exchange-coupled composite (ECC) media was performed with a data signal density of over 2 Tb/in2. Magnetic printing is a promising method of recording a servo signal onto an ECC media with data signal densities beyond 2 Tb/in2. The printing performance was close to 100% at servo signal densities of 1.0 and 1.7 Tb/in2. There was an optimum intergrain coupling strength in ECC media at each servo signal density, and as the servo signal density increased, the optimum intergrain coupling strength became weaker

Non-invasive assessment of arterial stiffness using oscillometric blood pressure measurement

<p>Abstract</p> <p>Background</p> <p>Arterial stiffness is a major contributor to cardiovascular diseases. Because current methods of measuring arterial stiffness are technically demanding, the purpose of this study was to develop a simple method of evaluating arterial stiffness using oscillometric blood pressure measurement.</p> <p>Methods</p> <p>Blood pressure was conventionally measured in the left upper arm of 173 individuals using an inflatable cuff. Using the time series of occlusive cuff pressure and the amplitudes of pulse oscillations, we calculated local slopes of the curve between the decreasing cuff pressure and corresponding arterial volume. Whole pressure-volume curve was derived from numerical integration of the local slopes. The curve was fitted using an equation and we identified a numerical coefficient of the equation as an index of arterial stiffness (Arterial Pressure-volume Index, API). We also measured brachial-ankle (baPWV) PWV and carotid-femoral (cfPWV) PWV using a vascular testing device and compared the values with API. Furthermore, we assessed carotid arterial compliance using ultrasound images to compare with API.</p> <p>Results</p> <p>The slope of the calculated pressure-volume curve was steeper for compliant (low baPWV or cfPWV) than stiff (high baPWV or cfPWV) arteries. API was related to baPWV (<it>r </it>= -0.53, <it>P </it>< 0.05), cfPWV (<it>r </it>= -0.49, <it>P </it>< 0.05), and carotid arterial compliance (<it>r </it>= 0.32, <it>P </it>< 0.05). A stepwise multiple regression analysis demonstrated that baPWV and carotid arterial compliance were the independent determinants of API, and that API was the independent determinant of baPWV and carotid arterial compliance.</p> <p>Conclusions</p> <p>These results suggest that our method can simply and simultaneously evaluate arterial stiffness and blood pressure based on oscillometric measurements of blood pressure.</p

Newly established cell lines from mouse oral epithelium regenerate teeth when combined with dental mesenchyme

The present study attempted to examine whether clonal cell lines of the oral epithelium can differentiate into ameloblasts and regenerate tooth when combined with dental germ mesenchyme. Clonal cell lines with a distinct morphology were established from the oral epithelium of p53-deficient fetal mice at embryonic day 18 (E18). The strain of mouse is shown to be a useful source for establishing clonal and immortalized cell lines from various tissues and at various stages of development. Tooth morphogenesis is almost completed and the oral epithelium is segregated from the dental epithelium at E18. In RT-PCR analysis of cell lines, mucosal epithelial markers (cytokeratin 14) were detected, but ameloblast markers such as amelogenin and ameloblastin were not detected when cells were cultured on plastic dish. They formed stratified epithelia and expressed a specific differentiation marker (CK13) in the upper layer when cultured on feeder layer or on collagen gel for 1–3 wk, demonstrating that they are of oral mucosa origin. Next, bioengineered tooth germs were prepared with cell lines and fetal molar mesenchymal tissues and implanted under kidney capsule for 2–3 wk. Five among six cell lines regenerated calcified structures as seen in natural tooth. Our results indicate that some oral epithelial cells at E18 possess the capability to differentiate into ameloblasts. Furthermore, cell lines established in the present study are useful models to study processes in tooth organogenesis and tooth regeneration

Taurine supplementation enhances endurance capacity by delaying blood glucose decline during prolonged exercise in rats

Taurine enhances physical performance; however, the underlying mechanism remains unclear. This study examined the effect of taurine on the overtime dynamics of blood glucose concentration (BGC) during endurance exercise in rats. Male F344 rats were subjected to transient treadmill exercise until exhaustion following 3 weeks of taurine supplementation or non-supplementation (TAU and CON groups). Every 10 min during exercise, BGC was measured in blood collected through cannulation of the jugular vein. Gluconeogenesis-, lipolysis-, and fatty acid oxidation-related factors in the plasma, liver, and skeletal muscles were also analyzed after 120-min run. Exercise time to exhaustion was significantly longer with taurine supplementation. BGC in the two groups significantly increased by 40 min and gradually and significantly decreased toward the respective exhaustion point. The decline in BGC from the peak at 40 min was significantly slower in the TAU group. The time when the once-increased BGC regressed to the 0-time level was significantly and positively correlated with exercise time until exhaustion. At the 120-min point, where the difference in BGC between the two groups was most significant, plasma free fatty acid concentration and acetyl-carnitine and N-acetyltaurine concentrations in skeletal muscle were significantly higher in the TAU group, whereas glycogen and glucogenic amino acid concentrations and G6Pase activity in the liver were not different between the two groups. Taurine supplementation enhances endurance capacity by delaying the decrease in BGC toward exhaustion through increases of lipolysis in adipose tissues and fatty acid oxidation in skeletal muscles during endurance exercise

Granulomatosis with Polyangiitis Localized in the Greater Omentum

Granulomatosis with polyangiitis (GPA) is known as anti-neutrophil cytoplasmic antibody- (ANCA-) associated small vessel vasculitis and typically manifests as pulmonary-renal syndrome, but the disease is not limited to pulmonary or renal systems. The inflammation can involve whole body organs. In addition, the ANCA titer does not always become positive. Here, we describe the case of a 91-year-old man who presented with umbilical pain and fever of unknown origin. Only the increased computed tomography value of the greater omentum suggested intra-abdominal inflammation; however, serological examinations, including the ANCA level, could not reveal the focus or cause of symptoms. Finally, the histopathological examination of specimens surgically excised from the greater omentum demonstrated GPA limited to the greater omentum. This report reminds physicians to consider GPA in the differential diagnosis of acute abdominal pain or fever of unknown origin

Phase II study of trifluridine/tipiracil (TAS‑102) therapy in elderly patients with colorectal cancer (T‑CORE1401): geriatric assessment tools and plasma drug concentrations as possible predictive biomarkers

Purpose The current study aimed to determine the efficacy of trifluridine/tipiracil for elderly patients with advanced colorectal cancer. Methods This single-arm, open-label, multicenter, phase II study included elderly patients aged 65 years or more who had fluoropyrimidine-refractory advanced colorectal cancer and received trifluridine/tipiracil (70 mg/m2, days 1–5 and 8–12, every 4 weeks). The primary endpoint was progression-free survival (PFS), while secondary endpoints included overall survival (OS), overall response rate (ORR), toxicities, association between efficacy and geriatric assessment scores, and association between toxicity and plasma drug concentrations. Results A total of 30 patients with a mean age of 73 years were enrolled. Median PFS was 2.3 months (95% confidence interval, 1.9–4.3 months), while median OS was 5.7 months (95% confidence interval, 3.7–8.9 months). Patients had an ORR of 0%, with 57% having stable disease. Grade 4 neutropenia was observed in 13% of the patients. Patients with a higher G8 score (15 or more) showed longer PFS than those with a lower G8 score (median 4.6 vs. 2.0 months; p = 0.047). Moreover, patients with grade 3 or 4 neutropenia showed higher maximum trifluridine concentrations than those with grade 1 or 2 neutropenia (mean 2945 vs. 2107 ng/mL; p = 0.036). Discussion The current phase II trial demonstrated that trifluridine/tipiracil was an effective and well-tolerated option for elderly patients with advanced colorectal cancer. Moreover, geriatric assessment tools and/or plasma drug concentration monitoring might be helpful in predicting the efficacy and toxicities in elderly patients receiving this drug. Trial registration number UMIN000017589, 15/May/2015 (The University Hospital Medical Information Network