Conjugate addition of methanol to 3-buten-2-one to form 4-methoxy-butan-2-one proceeds effectively over the solid base catalysts such as alkaline earth oxides, strontium hydroxide, barium hydroxide, ...and alumina supported potassium fluoride and hydroxide at a reaction temperature of 273
K. The catalytic activities of magnesium oxide, calcium oxide, and alumina supported KF catalyst were not much affected by exposure of the catalysts to carbon dioxide or air.
Petal color change in morning glory Ipomoea tricolor cv. Heavenly Blue, from red to blue, during the flower-opening period is due to an unusual increase in vacuolar pH (pHv) from 6.6 to 7.7 in ...colored epidermal cells. We clarified that this pHv increase is involved in tonoplast-localized Na+/H+ exchanger (NHX). However, the mechanism of pHv increase and the physiological role of NHX1 in petal cells have remained obscure. In this study, synchrony of petal-color change from red to blue, pHv increase, K+ accumulation, and cell expansion growth during flower-opening period were examined with special reference to ItNHX1. We concluded that ItNHX1 exchanges K+, but not Na+, with H+ to accumulate an ionic osmoticum in the vacuole, which is then followed by cell expansion growth. This function may lead to full opening of petals with a characteristic blue color. (Communicated by Ryoji NOYORI, M.J.A.)
Aim
Sofosbuvir (SOF), a nucleotide analog pro‐drug, targets hepatitis C virus (HCV) NS5B polymerase and shows potential for treating HCV infection, given its high efficacy and good barrier to ...resistance. However, in addition to the rare resistant‐associated variant (RAV) of non‐structural protein NS5B S282T, several new potential RAVs of SOF have been reported, especially related to HCV genotype 1b. However, the prevalence and characteristics of these RAVs have not been clarified.
Methods
We analyzed the prevalence of variants in the NS3/NS5A/NS5B regions in 96 patients treated with simeprevir (SMV) combination therapy, and the prevalence of RAVs in patients showing treatment failure was determined by direct‐ or deep‐sequencing methods. Associations between these potential RAVs and clinical factors were also analyzed.
Results
Prevalence of NS5B RAV C316N was high (46.9%, 45/96), whereas that of NS5B L159F was relatively low (1.04%, 1/96); however, deep sequencing showed that 30.0% of patients with C316N also had NS5B RAV L159F. Additionally, there was no significant relationship between the existence of potential NS5B and NS5A or NS3 RAVs. However, the presence of NS5B C316N was significantly associated with an HCV core amino acid 91 substitution. No significant difference was detected between each RAV and sustained virological response in simeprevir combination therapy.
Conclusion
We provide clear evidence of the high prevalence of two potential naturally occurring NS5B RAVs (C316N and L159F) in Japan. It may be important to pay particular attention to these new potential RAVs, especially when using SOF‐based therapy in patients with RAVs due to previous direct‐acting antiviral therapy failure.
Background Little information is available regarding the incidence of aortic dissection or rupture in patients with a dilated ascending aorta after aortic valve replacement (AVR). The present ...clinical study aimed to demonstrate the incidence of aortic complications after AVR in patients with a dilated ascending aorta and to clarify those risk factors associated with the progression of a dilated ascending aorta or late aortic events. Methods and Results A total of 35 patients with a dilated ascending aorta at the time of AVR were enrolled. A dilated ascending aorta was defined as 40 mm or greater in diameter by preoperative computed tomography or operative findings. The baseline ascending aorta diameter ranged from 40 to 55 mm with a mean of 44.8±4.4 mm. There was a high frequency of bicuspid valve disease in patients with a dilated ascending aorta (57%). The mean follow-up interval was 8.1±3.5 years (range: 2.3-13). Aortic events occurred in 5 patients (aortic dissection in 1, rupture in 2, reoperation in 2) during the follow-up. One aortic dissection developed at a baseline aortic size of 42 mm, whereas 2 aortic ruptures occurred at baseline aortic sizes of 47 mm and 50 mm. There was no statistically significant univariate association between any of the patient clinical characteristics and late aortic events or ascending aortic progression. Conclusion Although the clinical course of patients with a dilated ascending aorta is unpredictable, aortic events may occur even in patients with a baseline aortic diameter of <50 mm. Therefore, preventive aortic surgery at the time of AVR should be considered to prevent aortic dissection or rupture in patients with an even slightly dilated ascending aorta with a diameter of 40 to 50 mm, unless the patient has a high operative risk or older age. (Circ J 2005; 69: 392 - 396)
The fracture toughness and hardness of Ti (C0.7N0.3)-19Mo2C-xNbC-24Ni cermets (x = 0, 5, 20) were studied. Fracture toughness of 5 NbC was the largest, and it of 20 NbC was the lowest. The ...microstructures of all the cermets consisted of Ti (C,N) and solid soluted Ti (C,N) hard phase, and Ni binder phase. The solid soluted Ti (C,N) surrounded Ti (C,N), namely, core-rim structures were observed in 0NbC and 5NbC. On the other hand, the isolated Ti (C,N) and solid soluted Ti (C,N) were observed in 20NbC, as a result of the phase separation between Ti (C,N) core and solid soluted Ti (C,N).
WC-FeAl composites were fabricated by vacuum sintering technique from mixture of WC and FeAl powders containing various oxygen content. Mechanical properties such as hardness, fracture toughness and ...transverse rupture strength were influenced by the oxygen content in the powders. Control of the oxygen content was succeeded by changing the powder preparation process. Contrary to expectations, the reduction of oxygen content led to degrade the fracture toughness and transverse rupture strength of the composites. This result was attributed to the microstructural change in the sintered composite. The sintered composite of lower oxygen content exhibited WC grain growth or inhomogeneous microstructure, which can be the cause of degradation of those mechanical properties. It was concluded that the oxygen content was one of the key factors to influence the microstructure or mechanical properties of WC-FeAl composites.
TiC based cermet is a candidate material for alternatives of WC-Co used in tools/dies. Ordinary, Ni and Co, etc. are used as a metal binder of TiC based cermet. They are kinds of rare metals, ...therefore it is desired that metal binders are also replaced with the ubiquitous materials. FeAl intermetallic alloys are one of candidate materials of alternative rare metal binder made from ubiquitous materials. FeAl is well-known as an extremely resistance material to corrosion under oxidizing atmospheres, sulfidizing atmospheres, and in molten salts. Combination of intermetallic and carbide, the hardness is very high, but it would be brittle. In this work, TiC-FeAl alloys are made by wet milling and pulsed electric current sintering to improve transverse rupture strength while the hardness is kept. We achieved that TiC-40 vol. % (Fe-40 at. % Al) alloy with hardness of 17.7 GPa and T.R.S. of 1.9 GPa.
The integrated interleaving error correcting scheme is a coding scheme for combining codes with different error correcting capabilities. This method is applied to channels in which a data sequence is ...interleaved, e.g., magnetic recording channels. We propose a decoding method which enhances the error correcting capability of the scheme. By using the method, we can correct more errors which occur in retrieved data sequences.
The fracture toughness and hardness of Ti (C sub(0.7) N sub(0.) sub(3))-19Mo sub( 2) C-x NbC-24Ni cermets (x= 0, 5, 20) were studied. Fracture toughness of 5 NbC was the largest, and it of 20 NbC was ...the lowest. The microstructures of all the cermets consisted of Ti (C,N) and solid soluted Ti (C,N) hard phase, and Ni binder phase. The solid soluted Ti (C,N) surrounded Ti (C,N), namely, core-rim structures were observed in 0NbC and 5NbC. On the other hand, the isolated Ti (C,N) and solid soluted Ti (C,N) were observed in 20NbC, as a result of the phase separation between Ti (C,N) core and solid soluted Ti (C,N).
Abstract Background and purpose To compare the efficacy and toxicity of short-course carbon ion radiotherapy (C-ion RT) for patients with hepatocellular carcinoma (HCC) in terms of tumor location: ...adjacent to the porta hepatis or not. Materials and methods The study consisted of 64 patients undergoing C-ion RT of 52.8 GyE in four fractions between April 2000 and March 2003. Of these patients, 18 had HCC located within 2 cm of the main portal vein (porta hepatis group) and 46 patients had HCC far from the porta hepatis (non-porta hepatis group). We compared local control, survival, and adverse events between the two groups. Results The 5-year overall survival and local control rates were 22.2% and 87.8% in the porta hepatis group and 34.8% and 95.7% in the non-porta hepatis group, respectively. There were no significant differences ( P = 0.252, P = 0.306, respectively). Further, there were no significant differences in toxicities. Biliary stricture associated with C-ion RT did not occur. Conclusions Excellent local control was obtained independent of tumor location. The short-course C-ion RT of 52.8 GyE in four fractions appears to be an effective and safe treatment modality in the porta hepatis group just as in the non-porta hepatis group.
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