323 research outputs found
MovieMaker: A Parallel Movie-Making Software for Large Scale Simulations
We have developed a parallel rendering software for scientific visualization
of large-scale, three-dimensional, time development simulations. The goal of
this software, MovieMaker, is to generate a movie, or a series of visualization
images from totally one TB-scale data within one night (or less than 12 hours).
The isocontouring, volume rendering, and streamlines are implemented.
MovieMaker is a parallel program for the shared memory architecture with
dynamic load balancing and overlapped disk I/O.Comment: 3pages, 5figures, submitted to J. Plasma Physcs (special issue for
19th ICNSP
Pressure-induced defects in zirconates
Defects, e.g. vacancies and interstitials, play an important role on the physical properties of oxides, especially on their ionic transport. Those defects in oxides are generally controlled and analyzed as functions of dopant concentration, c, temperature, T, and oxygen chemical potential, O2, but not of total pressure, P. This is not surprising given that a molar volume, Vm, of solids is much smaller than that of gas phase by a factor of ≈1/1000. Meanwhile, under high pressure such as several GPa, the effect of total pressure on free energy, i.e. VmP, reaches 20~100 kJ/mol, which is high enough to affect the defect formation and migration in solids. In fact, pressure-induced phenomena are recently of great interest in solid state ionics. In this study, we focus on the pressure effects on the defect formation in some stabilized ZrO2 and acceptor-doped BaZrO3.
For Y-stabilized ZrO2, reduction was found to be enhanced under high pressure. Figure 1 shows the lattice constant of 8YSZ electrochemically reduced under high pressure as a function of oxygen deficiency introduced. Under high pressure such as 1 to 6 GPa, 8YSZ was easily reduced even at 3VDC at 500°C. The oxygen deficiency reaches = 0.05. Unlike reduced CeO2 which shows lattice expansion, the reduced 8YSZ shows 0.5% smaller lattice constant. The lattice shrinkage was also confirmed by DFT calculations. This supports that applying high pressure, which in general enhances a reaction with negative volume change, enhances the reducing reaction of cubic ZrO2. Figure 2 shows the temperature dependence of electrical conductivity of reduced 8YSZ. The reduced 8YSZ appears to show mixed ionic and electronic conduction; major carrier is electrons. Acceptor-doped BaZrO3 was also subjected to high pressure on the order of GPa. Their defect equilibrium and proton conductivity will be also discussed.
Please click Additional Files below to see the full abstract
Vertically stacked graphene tunnel junction with structured water barrier
We report a vertically stacked graphene tunnel junction with an atomically thin insulating layer for novel function devices. The insulating water layer sandwiched between graphene samples as a tunnel barrier which is fabricated through deionized (DI) water treatment of epitaxial graphene. Two graphene samples fabricated by SiC thermal decomposition are directly bonded to each other in a face-to-face manner. Vertically stacked graphene samples without DI water treated formed an ohmic junction. By inserting the structured water layer as tunnel barrier, the stacked junction exhibits Direct tunneling (DT) characteristics in a low-electric-field regime and Fowler-Nordheim tunneling (FNT) characteristics in a high-electric-field regime. The thickness of the structured water layer is estimated to be 0.28 nm by fitting the FNT formula. The very thin structured water layer is stable as tunnel barrier on epitaxial graphene for diode devices, which will have a widely application in electronic devices
Fine structure of OPCs observed by SBF-SEM
Oligodendrocyte precursor cells (OPC) arise from restricted regions of the central nervous system (CNS) and differentiate into myelin-forming cells after migration, but their ultrastructural characteristics have not been fully elucidated. This study examined the three-dimensional ultrastructure of OPCs in comparison with other glial cells in the early postnatal optic nerve by serial block-face scanning electron microscopy. We examined 70 putative OPCs (pOPC) that were distinct from other glial cells according to established morphological criteria. The pOPCs were unipolar in shape with relatively few processes, and their Golgi apparatus were localized in the perinuclear region with a single cisterna. Astrocytes abundant in the optic nerve were distinct from pOPCs and had a greater number of processes and more complicated Golgi apparatus morphology. All pOPCs and astrocytes contained a pair of centrioles (basal bodies). Among them, 45% of pOPCs extended a short cilium, and 20% of pOPCs had centrioles accompanied by vesicles, whereas all astrocytes with basal bodies had cilia with invaginated ciliary pockets. These results suggest that the fine structures of pOPCs during the developing and immature stages may account for their distinct behavior. Additionally, the vesicular transport of the centrioles, along with a short cilium length, suggests active ciliogenesis in pOPCs
Ectopic varices in a right diaphragm that ruptured into the pleural cavity.
The term ectopic varices is used to describe dilated portosystemic collateral veins in unusual locations other than the gastroesophageal region. We recently experienced a rare case of ectopic varices that developed in the right diaphragm and ruptured into the pleural cavity. A 68-year-old female with hepatocellular carcinoma complicated with liver cirrhosis was admitted due to an acute onset of dyspnea and right bloody pleural effusion. Because of the patient's advanced hepatocellular carcinoma and poor condition, conservative therapies such as hemostats and blood transfusion were selected. Even though the bleeding to the pleural cavity stopped spontaneously, the patient died due to a progression of liver failure. Autopsy revealed a huge collateral vein in the right diaphragm. The etiology, prevalence, relationship with portal hypertension, and treatment of ectopic varices are discussed herein
ICBT survey for cervical cancer
To review the current status of, and labor expended for (in terms of time required), intracavitary brachytherapy (ICBT) in definitive radiotherapy/chemoradiotherapy for cervical cancer patients, two national surveys were performed. The first survey was conducted between July and August 2016 and consisted of a questionnaire of 12 items regarding ICBT procedures for cervical cancer, which was sent to 173 centers installed with high-dose-rate remote after-loading brachytherapy systems. Between November and December 2016, another survey was performed in 79 centers to evaluate labor required for ICBT procedures in terms of time spent and number of staff involved. In the first survey, the response rate was 77% of the 173 centers. ICBT was performed for cervical cancer in 118 (89%) centers. Imaging modalities used after applicator insertion were X-ray alone in 46 (40%), computed tomography in 69 (60%) and magnetic resonance imaging in 5 (4%) centers. Three-dimensional (3D) planning was performed in 55 centers (48%). Fifty-five (70%) centers responded to the second survey regarding ICBT-mandated labor. The median cumulative duration of the entire ICBT procedure was 330 min (the sum of the times spent by each staff member) and was longer in the 3D image–guided brachytherapy (3D-IGBT) (405 min) than in the X-ray group (230 min). This trend was significant for the specific processes of image acquisition and treatment planning, especially for radiation oncologists. In definitive radiotherapy/chemoradiotherapy for cervical cancer patients, 3D-IGBT use has been gradually spreading in Japan. The present survey revealed that ICBT, especially 3D-IGBT, requires substantial labor and time from staff
The Molecular Mechanism Underlying Continuous Exercise Training-Induced Adaptive Changes of Lipolysis in White Adipose Cells
Physical exercise accelerates the mobilization of free fatty acids from white adipocytes to provide fuel for energy. This happens in several tissues and helps to regulate a whole-body state of metabolism. Under these conditions, the hydrolysis of triacylglycerol (TG) that is found in white adipocytes is known to be augmented via the activation of these lipolytic events, which is referred to as the “lipolytic cascade.” Indeed, evidence has shown that the lipolytic responses in white adipocytes are upregulated by continuous exercise training (ET) through the adaptive changes in molecules that constitute the lipolytic cascade. During the past few decades, many lipolysis-related molecules have been identified. Of note, the discovery of a new lipase, known as adipose triglyceride lipase, has redefined the existing concepts of the hormone-sensitive lipase-dependent hydrolysis of TG in white adipocytes. This review outlines the alterations in the lipolytic molecules of white adipocytes that result from ET, which includes the molecular regulation of TG lipases through the lipolytic cascade
Height Constitutes an Important Predictor of Mortality in End-Stage Renal Disease
Aim. Height is an important determinant of augmentation index (AI) that anticipates cardiovascular prognosis. There is a scanty of the data whether short height predicts survival in patients with end-stage renal diseases, a high risk population. Methods. Fifty two hypertensive patients with type 2 diabetic nephropathy receiving hemodialysis and 52 patients with nondiabetic nephropathy were enrolled. In addition to AI estimated with radial artery tonometry, classical cardiovascular risk factors were considered. Patients were followed for 2 years to assess cardiovascular prognosis. Results. Cox hazards regression revealed that both smoking and shortness in height independently contributed to total mortality and indicated that smoking as well as the presence of left ventricular hypertrophy predicted cardiovascular mortality. Our findings implicated that high AI, the presence of diabetes, and low high-density lipoprotein cholesterol were significant contributors to cardiovascular events. Conclusions. Our findings provide new evidence that shortness in height independently contributes to total mortality in hemodialysis patients
JASTRO IC/IS Guideline for Gynecologic Cancers
It has been postulated that the combination of intracavitary and interstitial brachytherapy (IC/IS) is effective and safe for large and irregularly shaped uterine cervical cancer patients. However, due to its invasiveness compared to conventional intracavitary brachytherapy (ICBT), it has to be said that the implementation speed of IC/IS is slow. Until now, there have been no guidelines for required equipment, human resources, and procedural guide focusing solely on IC/IS. The purpose of this guideline is to provide radiation oncologists and medical physicists who wish to start IC/IS with practical and comprehensive guidance for a safe IC/IS introduction and to help accelerate the spread of the utilization of IC/IS nationwide. This is the English translation of the Japanese IC/IS Guidelines, and it was created in an effort to share the Japanese approach to the management of locally advanced uterine cervical cancer worldwide
- …