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931.
Takaki Habuchi Prof. Dr. Takao Yamaguchi Prof. Dr. Satoshi Obika 《Chembiochem : a European journal of chemical biology》2019,20(8):1060-1067
Oligonucleotides containing bridged nucleic acids (BNAs) show high duplex-forming ability towards target single-stranded RNA, so many BNAs have been developed for antisense applications. Amide-bridged nucleic acids (AmNAs), which are BNA analogues bearing an amide bond at the bridge, exhibit high duplex-forming ability, enzymatic stability, and antisense activity; thus, the AmNA motif represents a promising BNA scaffold. The high enzymatic stability of the AmNA motif is presumably attributable to the bulky amide structure, because it inhibits the access of nucleases to the phosphodiester linkage. Here, to improve enzymatic stability further, we designed thioAmNAs: thioamide-bridged nucleotides that have a bulkier bridge structure than AmNA. The synthesis of thioAmNAs bearing either thymine (thioAmNA-T) or 2-thiothymine (thioAmNA-S2T) bases was successful, and the obtained monomers were introduced into designed oligonucleotides without noticeable by-product generation. The thioAmNA-T- and thioAmNA-S2T-modified oligonucleotides showed strong binding affinity toward complementary single-stranded RNA, with the thioAmNA-S2T-modified oligonucleotide displaying excellent base-discrimination capability. Moreover, both thioAmNA-T and thioAmNA-S2T endowed oligonucleotides with higher resistance to enzymatic degradation than AmNA-T. These results indicate that thioAmNAs are potentially useful chemical modifications for oligonucleotide-based therapeutics. 相似文献
932.
该文针对摄入醋酸菌对于酒精性肝损伤的影响进行了评价。将C57BL/6J小鼠(8周龄,雄性,22~27 g)分为对照组(非乙醇给药组)、乙醇组(给予2.5 g/kg乙醇)、乙醇+醋酸菌组(给予2.5 g/kg乙醇+10 mg醋酸菌),分别每天给药3次,连续经口给药14 d,测定了血清谷草转氨酶(AST)、谷丙转氨酶(ALT)及肝脏油脂浓度。结果表明,与对照组相比较,乙醇组小鼠的AST与ALT浓度,肝脏甘油三酯与胆固醇浓度显著增高(P<0.05);乙醇+醋酸菌组的数值则显著低于乙醇组(P<0.05)。以上结果表明,摄入醋酸菌有可能会减轻酒精性肝损伤。 相似文献
933.
Satoshi Fukuta Keita Ogawa Masaki Nomura Mariko Yamasaki Yasutoshi Sasaki 《Holz als Roh- und Werkstoff》2017,75(4):595-602
In this study sound insulation of walls was evaluated using wood insulation mat and plywood jointed with a combination of adhesive tape and wood dowels. Building of actual wall assembly test specimens and evaluating their sound insulation revealed that the sound transmission loss for jointing using a combination of adhesive tape and wood dowels was considerably higher than that using nails, for middle and high frequency ranges of 2 kHz and above. When comparing heat-insulating materials (sound-absorbing materials), the test specimen using high-density glass wool had greater sound insulation than the specimen using low-density materials, and the specimen using wooden heat-insulating/sound-absorbing materials showed roughly the same properties as glass wool of 20 % higher density. When the sound insulation for impact sounds of the experimental specimen (joined with adhesive tape and using wooden heat-insulating/sound-absorbing materials) was compared to a specimen with a typical composition (joined with nails and using glass wool), the former proved to have better sound insulation, by approximately 10 dB for light impact sounds between 400 and 800 Hz and approximately 5 dB for higher frequencies. For heavy impact sounds, the experimental specimen displayed a greater sound insulation for all frequencies, by 5–10 dB at frequencies of around 100 Hz and of 400 Hz and above. 相似文献
934.
Tomohisa Okazaki Satoshi Seino Junichiro Kugai Yuji Ohkubo Hiroaki Nitani Takashi Nakagawa 《Journal of Nuclear Science and Technology》2017,54(4):472-480
The process of nanoparticle formation by radiochemical synthesis in a heterogeneous system has been investigated considering the effects of the metal ion location in the reaction medium. PtCu nanoparticles supported on carbon and γ-Fe2O3 were synthesized using a high-energy electron beam. The metal ions in the precursor were categorized as those dissolved in solution, adsorbed on support, and precipitated. The ratio of metal ions in the solution was varied prior to the electron beam irradiation and its effects on the synthesized particle structures were examined. The nanoparticles were characterized by inductively coupled plasma-atomic emission spectrometry, transmission electron microscopy, X-ray diffraction, and X-ray absorption spectroscopy. A PtCu alloy and CuO were immobilized on the support in all the samples. The PtCu alloy nanoparticle composition depended on the Cu ion content in the solution. The nanoparticle formation mechanism could be explained using the obtained results. Metal ions present in the solution resulted in formation of the alloy. The adsorbed ions also contributed to the alloy formation by desorbing from the support when irradiated. On the other hand, alloy formation with Pt from the precipitated Cu ions was found to be difficult. 相似文献
935.
Towards the development of a mechanical model that can be part of multi-physical analysis of frozen soils, a program of systematic frozen-unfrozen parallel triaxial tests at different temperatures and strain rates was conducted. The mechanical behavior of the reconstituted high-plasticity clay samples was investigated and interpreted through a state concept based on Ladanyi and Morel’s (1990) postulate on the unique relationship between the inter-particle “effective” stress and the strain path. The Critical State Lines (CSLs) for clay specimens frozen undrained were mapped by referring to the shear behavior of unfrozen specimens sharing the same strain history. With other conditions set identical, the shear strength linearly increased with a decrease in the temperature for the range from ?10 °C to ?2 °C, and log-linearly increased with an increase in the strain rate for the range from 0.001%/min to 0.1%/min. Direct comparison of the strain-rate effects between frozen and unfrozen specimens with identical strain paths and states in the soil skeleton clearly indicates that the viscoplasticity derives from that of pore ice. A conceptual interpretative framework invoking temperature- and strain rate-dependent state bounding surfaces and CSLs was proposed to describe the behavior of frozen soils under steady and non-steady temperature and strain rate. The above observations of the behavioral features of frozen and unfrozen soils, with further experimental work, are expected to lead to the construction of a unified framework for describing the behavior under both states and the transition between them. 相似文献
936.
This article seeks to unify two subfields of psychology that have hitherto stood separately: evolutionary psychology and intelligence research/differential psychology. I suggest that general intelligence may simultaneously be an evolved adaptation and an individual-difference variable. Tooby and Cosmides's (1990a) notion of random quantitative variation on a monomorphic design allows us to incorporate heritable individual differences in evolved adaptations. The Savanna–IQ Interaction Hypothesis, which is one consequence of the integration of evolutionary psychology and intelligence research, can potentially explain why less intelligent individuals enjoy TV more, why liberals are more intelligent than conservatives, and why night owls are more intelligent than morning larks, among many other findings. The general approach proposed here will allow us to integrate evolutionary psychology with any other aspect of differential psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
937.
Kohno H Nogami T Takeda S Ohno Y Yonenaga I Ichikawa S 《Journal of nanoscience and nanotechnology》2010,10(10):6655-6658
Electron transport across individual Si nanochains and silicide nanochains is investigated using a micro-manipulator in a transmission electron microscope. The current increases nonlinearly with increasing the bias voltage. Electrical breakdowns occur with a current typically as large as 10(1)-10(2) nA. Furthermore, some FN plots exhibit a bend presumably due to the formation of a heavily distorted nanotube of carbon. 相似文献
938.
Satoshi Semboshi Naofumi Ohtsu Yoshiteru Mizukoshi Naoya Masahashi 《Thin solid films》2010,519(2):719-724
The structure and dielectric properties of an anodic oxide on Nb solid solution (Nbss)/Nb2N two phase alloys were investigated. The anodized specimens were covered with two types of anodic oxides on the Nbss and Nb2N phases, respectively. The relative permittivity and leakage current density of the anodized specimens can be explained by the combination of the two oxides; the relative permittivity of the specimens increased with the volume fraction of the oxide on the Nbss phase, because the relative permittivity of the oxide on the Nbss phase is higher than that on the Nb2N phase. The leakage current was suppressed irrespective of the constitute phases as compared with the anodized pure Nb, because it was reduced in both the oxides on the Nbss and Nb2N phases. 相似文献
939.
Nobuhiro Kumada Hideyuki Ogiso Keiko Shiroki Satoshi Wada Yoshinori Yonesaki Takahiro Takei Nobukazu Kinomura 《Materials Letters》2010,64(3):383-385
The solid solution (Ba1−2xBi2x)(CuxTi1− x)O3 (0.0 < x ≤ 0.10) was prepared by conventional high temperature reaction. In the region of x ≤ 0.040 single phases of tetragonal perovskite-type compounds were obtained and the c-axis increased up to x = 0.015 and the maximum of the a/c ratio was 1.0123 at x = 0.010. In x > 0.040 a small amount of an unknown impurity phase appeared in addition to a tetragonal perovskite-type phase. The Curie temperature Tc increased to 140 °C at x = 0.010. Rising Tc was confirmed by temperature dependence of the dielectric constants and the endothermic peaks observed in DTA curves. This is the first example for rising Tc in the solid solution based on BaTiO3 except for doping of Pb2+ ion. 相似文献
940.