299 research outputs found
On cosmic-ray production efficiency at supernova remnant shocks propagating into realistic diffuse interstellar medium
Using three-dimensional magnetohydrodynamics simulations, we show that the
efficiency of cosmic-ray (CR) production at supernova remnants (SNRs) is
over-predicted if it could be estimated based on proper motion measurements of
H filaments in combination with shock-jump conditions. Density
fluctuations of upstream medium make shock waves rippled and oblique almost
everywhere. The kinetic energy of the shock wave is transferred into that of
downstream turbulence as well as thermal energy which is related to the shock
velocity component normal to the shock surface. Our synthetic observation shows
that the CR acceleration efficiency as estimated from a lower downstream plasma
temperature, is overestimated by 10-40%, because rippled shock does not
immediately dissipate all upstream kinetic energy.Comment: 7 pages, 3 figures, 1 table, accepted for publication in ApJ; the
paper with full resolution images is
http://www.phys.aoyama.ac.jp/~ryo/papers/shimoda2015.pd
A highly sensitive chemiluminescence assay for superoxide detection and chronic granulomatous disease diagnosis
Reactive oxygen species (ROS) produced by neutrophils are crucial for defense against infectious diseases, and the adequate measurement of ROS levels is an important way to evaluate the possibility of infections. The fluorescent probe dihydrorhodamine 123 has been applied exclusively to the measurement of ROS thus far. We developed a novel method for detecting ROS, which utilizes the chemiluminescent probes Luminol and Diogenes. The new method quantitatively detects ROS produced by as few as 10 to 104 neutrophils. Furthermore, this method can detect ROS levels in one microliter of whole blood or ROS produced by Epstein-Barr immortalized B lymphocytes. This method will be valuable for prompt diagnosis of neonatal chronic granulomatous diseases in which neutrophils aberrantly produce superoxide
Induction of fatty liver by Coleus forskohlii extract through enhancement of de novo triglyceride synthesis in mice
AbstractColeus forskohlii extract (CFE), an herbal ingredient, is used for weight-loss products. CFE's alleged efficacy is attributed to forskolin. However, CFE has been shown to induce fatty liver in mice, with components other than forskolin playing a part in this effect. The present study addressed the underlying mechanism of CFE-induced fatty liver by analyzing changes in CFE-treated mice of lipid concentrations and of the levels of mRNAs encoding enzymes and transcription factors known to be related to fatty liver. Mice were fed a diet containing 0, 0.3 and 1% CFE for 2 weeks. CFE at 1% clearly induced fatty liver, as demonstrated by histological examination and confirmed by increases in triglyceride concentrations in liver. However, treated mice did not exhibit elevation in plasma levels of non-esterified fatty acids. Comprehensive analysis of liver mRNA levels revealed accumulation of multiple transcripts, including mRNAs encoding enzymes acetyl-CoA carboxylase and long-chain elongase; transcription factor peroxisome proliferator-activated receptor gamma (PPARγ); and lipid-droplet-associated fat-specific protein 27 (Fsp27). These findings suggest that the de novo synthesis and accumulation of triglyceride in the liver, through the enhanced expression of specific lipogenic mRNAs, is a major underlying mechanism of fatty liver induction by CFE
A Faster Constant-time Algorithm of CSIDH keeping Two Points
At ASIACRYPT 2018, Castryck, Lange, Martindale, Panny and Renes proposed CSIDH, which is a key-exchange protocol based on isogenies between elliptic curves, and a candidate for post-quantum cryptography. However, the implementation by Castryck et al. is not constant-time. Specifically, a part of the secret key could be recovered by the side-channel Attacks. Recently, Meyer, Campos and Reith proposed a constant-time implementation of CSIDH by introducing dummy isogenies and taking secret exponents only from intervals of non-negative integers. Their non-negative intervals make the calculation cost of their implementation of CSIDH twice that of the worst case of the standard (variable-time) implementation of CSIDH. In this paper, we propose a more efficient constant-time algorithm that takes secret exponents from intervals symmetric with respect to the zero. For using these intervals, we need to keep two torsion points in an elliptic curve and calculation for these points. We evaluate the costs of our implementation and that of Meyer et al. in terms of the number of operations on a finite prime field. Our evaluation shows that our constant-time implementation of CSIDH reduces the calculation cost by 28.23% compared with the implementation by Mayer et al. We also implemented our algorithm by extending the implementation in C of Meyer et al. (originally from Castryck et al.). Then our implementation achieved 152.8 million clock cycles, which is about 29.03% faster than that of Meyer et al. and confirms the above reduction ratio in our cost evaluation
Endobronchial Argon Plasma Coagulation for the Palliation of Recurrent Tracheobronchial Adenoid Cystic Carcinoma
This is a non-final version of an article published in final form in Journal of Bronchology, 14(4):278-280, October 2007.The standard treatment of adenoid cystic carcinoma (ACC) of the airway is surgery, if possible, because survival rate is better than other treatments including radiotherapy. Although ACC shows frequent recurrence during the long-term follow-up unless there has been a complete resection (negative surgical margin), no further treatments are recommended. This report describes how argon plasma coagulation using flexible bronchoscopy has been successfully employed in the treatment of ACC after conventional therapy in 1 case of recurrence after surgery and 2 cases of inoperable patients. All of the patients are alive and healthy more than 6 years after diagnosis.ArticleJournal of Bronchology. 14(4):278-280 (2007)journal articl
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