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排序方式: 共有1710条查询结果,搜索用时 31 毫秒
921.
922.
In this paper, we develop an algorithm for minimizing the L q norm of a vector whose components are linear fractional functions, where q is an arbitrary positive integer. The problem is a kind of sum-of-ratios optimization problem, and often occurs in computer vision. In that case, it is characterized by a large number of ratios and a small number of variables. The algorithm we propose here exploits this feature and generates a globally optimal solution in a practical amount of computational time. 相似文献
923.
Chikako Nishigori Eiji Nakano Taro Masaki Ryusuke Ono Seiji Takeuchi Mariko Tsujimoto Takehiro Ueda 《Photochemistry and photobiology》2019,95(1):140-153
Xeroderma pigmentosum (XP) is a rare autosomal recessive hereditary disease caused by deficiency in repair of DNA lesions generated by ultraviolet radiation and other compounds. Patients with XP display pigmentary change and numerous skin cancers in sun‐exposed sites, and some patients show exaggerated severe sunburns even upon minimum sun exposure as well as neurological symptoms. We conducted a nationwide survey for XP since 1980. In Japan, the frequency of the XP complementation group A is the highest, followed by the variant type; while in the Western countries, those of groups C or D are the highest. Regarding skin cancers in XP, basal cell carcinoma was the most frequent cancer that afflicted patients with XP, followed by squamous cell carcinoma, and malignant melanoma. The frequency of these skin cancers in patients with XP has decreased in these 20 years, and the age of onset of developing skin cancers is higher than those previously observed, owing to early diagnosis and education to patients and care takers on strict prevention from sunlight for patients with XP. On the other hand, the effective therapy for neurological XP has not been established yet, and this needs to be done urgently. 相似文献
924.
Masaki Takata 《Synchrotron Radiation News》2013,26(4):39-41
No matter the location, it is particularly important to achieve sustainable and efficient access to a synchrotron radiation (SR) facility in order for there to be rapid progress in science and technology. Asia-Oceania is now a vibrant and thriving area in terms of making feasible a broad expansion of access to SR facility services and laying the foundation for more competitive industrial science and future economic growth to which SR science can contribute. Recently, SR facilities have started to pop up, one after another, in the Asia-Oceania region. To enhance global cooperation for SR research in this region, the AOFSRR (Asia-Oceania Forum for Synchrotron Radiation Research) was established by Australia, China, South Korea, Singapore, Taiwan, Thailand, and Japan in 2006. The objective of the AOFSRR is to organize a general framework of collaboration for the development of science and technology of mutual benefit to advancing the research goals and promoting comprehensive cooperation in synchrotron radiation research in the Asia-Oceania region. 相似文献
925.
Masaki Matsui Toshihiro ShibataMasato Fukushima Yasuhiro KubotaKazumasa Funabiki 《Tetrahedron》2012,68(48):9936-9941
3-Butoxy-4-(1-butyl-3,3-dimethyl-3H-indol-2-ylidenemethyl)-3-cyclobut-1,2-dione exhibited the most intense florescence at fluorescence maxima 536 and 563 nm with fluorescence quantum yield 0.21 among any indolenine semi-squarylium dyes in the crystalline form due to the isolated dimer-type molecular packing and its suitable melting point. This compound showed aggregation-induced emission enhancement. 相似文献
926.
Experiments were carried out to examine the effects of a single porous-type roughness element on the insulated wall opposite the smooth heated plate on the heat transfer. The local heat transfer and drag coefficients depend on the porous diameter and the porosity. The local heat transfer coefficient takes a peak, PI, under the porous element in laminar flow. On the other hand, in turbulent flow, it takes two peaks, PI and P2, under and after the element, respectively. The position of peak P2 varies with the height of the element and the Reynolds number. The drag coefficient of the porous element is lower than that of the solid element. According to thermal performance at constant pumping power, this kind of element should be used in laminar flow. In addition, it is estimated that the porous element should be utilized in the composite effects (the turbulence increase and the thermal radiation shielding effect) of heat transfer in order to apply the element effectively. 相似文献
927.
Prof. Katsuhiko Ariga Mr. Masaki Ishii Dr. Taizo Mori 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6461-6472
Soft and flexible two-dimensional (2D) systems, such as liquid interfaces, would have much more potentials in dynamic regulation on nano–macro connected functions. In this Minireview article, we focus especially on dynamic motional functions at liquid dynamic interfaces as 2D material systems. Several recent examples are selected to be explained for overviewing features and importance of dynamic soft interfaces in a wide range of action systems. The exemplified research systems are mainly classified into three categories: (i) control of microobjects with motional regulations; (ii) control of molecular machines with functions of target discrimination and optical outputs; (iii) control of living cells including molecular machine functions at cell membranes and cell/biomolecular behaviors at liquid interface. Sciences on soft 2D media with motional freedom and their nanoarchitectonics constructions will have increased importance in future technology in addition to popular rigid solid 2D materials. 相似文献
928.
Kensuke Shigeta Masafumi Kikuchi Masaki Tanaka Shinya Takasaki Hisashi Oishi Tetsu Sado Yasushi Matsuda Masafumi Noda Yoshinori Okada Nariyasu Mano Hiroaki Yamaguchi 《Biomedical chromatography : BMC》2020,34(8):e4853
Sirolimus is used on patients after solid organ transplantation and on lymphangioleiomyomatosis (LAM) patients, and therapeutic drug monitoring is required in clinical practice. We have previously reported an accurate method for quantitative determination of sirolimus, but its sample preparation step was complicated. In this study, we developed a modified liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI–MS/MS) method for sirolimus quantification. A supported liquid extraction cartridge was used to purify sirolimus from whole blood and ion suppression was mostly prevented. The validation results met the acceptance criteria. This method was compared with the antigen conjugated magnetic immunoassay (ACMIA) and our previously reported method, using whole blood samples from LAM patients. Comparison of the Bland–Altman plots of the currently developed method and the previous method revealed no significant difference between the two methods (mean bias, −2.02%; 95% CI, −7.81–3.78). The values obtained using ACMIA were significantly higher than those obtained using the current method by 13.87% (95% CI, 6.49–21.25) owing to cross-reactivity. The degrees of cross reactivities in LAM patients and in organ transplant patients were similar, and our LC/ESI–MS/MS method precisely measured the blood concentrations of sirolimus. 相似文献
929.
Masaki Matsui Masato Fukushima Yasuhiro Kubota Kazumasa Funabiki Motoo Shiro 《Tetrahedron》2012,68(7):1931-1935
An N-butyl indolenine squarylium dye could include toluene and p-xylene and exhibited the solid-state fluorescence in near-infrared region (Fmax=761 nm) in crystalline form due to inhibition of π/π-interactions between the fluorophores. 相似文献
930.