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排序方式: 共有1324条查询结果,搜索用时 203 毫秒
1.
Virginia Veronica Visconti Ida Cariati Simona Fittipaldi Riccardo Iundusi Elena Gasbarra Umberto Tarantino Annalisa Botta 《International journal of molecular sciences》2021,22(8)
DNA methylation is one of the most studied epigenetic mechanisms that play a pivotal role in regulating gene expression. The epigenetic component is strongly involved in aging-bone diseases, such as osteoporosis and osteoarthritis. Both are complex multi-factorial late-onset disorders that represent a globally widespread health problem, highlighting a crucial point of investigations in many scientific studies. In recent years, new findings on the role of DNA methylation in the pathogenesis of aging-bone diseases have emerged. The aim of this systematic review is to update knowledge in the field of DNA methylation associated with osteoporosis and osteoarthritis, focusing on the specific tissues involved in both pathological conditions. 相似文献
2.
To enhance chemical stability and suppress of aggregation of magnetite nanoparticles (MNPs), which are used as a support for thermoresponsive copolymer immobilization, silica coating of the MNPs is applied via the electrooxidation method. Although the resulting silica coated-MNPs also formed aggregates, the size distribution of the aggregate shifted to smaller size range. Because of that, the surface area available for copolymer immobilization increased approximately 6.7 times at maximum as compared with that of the uncoated MNPs. It contributed to the increase of the amount of the immobilized copolymer on the silica-coated MNPs, which is approximately four times larger than that on the uncoated MNPs. Fe3O4 dissolution test confirmed enhancement of chemical stability of MNPs. The thermoresponsive copolymer immobilized on the silica-coated MNPs shows the ability to recycle Cu(II) ion from Cu(II) containing solution by changing temperature with significantly shorter time than those in other thermoresponsive adsorbents in gel form. 相似文献
3.
Karolina Storesund Francine Amon Anne Steen‐Hansen Shayesteh Haghighatpanah Ida Larsson 《火与材料》2021,45(1):181-190
The aim of this exploratory study has been to investigate the fire properties and environmental aspects of different upholstery material combinations, mainly for domestic applications. An analysis of the sustainability and circularity of selected textiles, along with lifecycle assessment, is used to qualitatively evaluate materials from an environmental perspective. The cone calorimeter was the primary tool used to screen 20 different material combinations from a fire performance perspective. It was found that textile covers of conventional fibres such as wool, cotton and polyester, can be improved by blending them with fire resistant speciality fibres. A new three‐dimensional web structure has been examined as an alternative padding material, showing preliminary promising fire properties with regard to ignition time, heat release rates and smoke production. 相似文献
4.
5.
The oxidation of Fe(II) with dissolved molecular oxygen was studied in sulfuric acid solutions containing 0.2 mol . dm-3 FeSO4 at temperatures ranging from 343 to 363 K. In solutions of sulfuric acid above 0.4 mol . dm-3, the oxidation of Fe (II) was found to proceed through two parallel paths. In one path the reaction rate was proportional
to both [Fe2+]2 and po2, exhibiting an activation energy of 51.6 . kJ mol-1. In another path the reaction rate was proportional to [Fe2+]2, [SO4-], and po2 with an activation energy of 144.6 kJ . mol-1. A reaction mechanism in which the SO4- ions play an important role was proposed for the oxidation of Fe(II). In dilute solutions of sulfuric acid below 0.4 mol
. dm-3, the rate of the oxidation reaction was found to be proportional to both [Fe(II)]2 and Po2, and was also affected by [H+] and [SO2-
4]. The decrease in [H+] resulted in the increase of reaction rate. The discussion was further extended to the effect of Fe (III) on the oxidation
reaction of Fe (II). 相似文献
6.
24 18–40 yr olds performed a memory-scanning task (S. Sternberg, 1966, 1969) in which probe letters were displayed unilaterally or bilaterally after sets of 2, 4, or 6 letters were memorized. The mean response time (RT) to bilateral presentations was significantly longer than the mean RT to unilateral presentations, but the slope of the set-size function was not affected, suggesting that presenting stimuli bilaterally affected stages other than memory scanning. There were no significant visual-field effects in either the bilateral or unilateral conditions, suggesting that memory scanning is not a lateralized process. There was no evidence that bilateral presentation increased visual-field differences. This is not consistent with D. B. Boles' (1983, 1990) hypothesis that visual-field asymmetry effects are more pronounced with bilateral than with unilateral presentation of stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Ida I. Sato J. Sekizawa T. Yoshimura H. Ito K. 《Antennas and Propagation, IEEE Transactions on》2002,50(6):821-826
The efficiency fractional efficiency bandwidth product (EB) that is expressed as a ratio of the radiation resistance to the absolute value of an input reactance of an antenna is used as a performance measure for small dielectric-loaded monopole antennas (DLMAs). The dependence of the efficiency bandwidth (EB) on the permittivity of the dielectric loading (i.e., the electrical volume) is experimentally investigated for the first time after we succeeded in measuring the small radiation resistance of the DLMAs precisely on the basis of the Wheeler cap method. As a result, it was found that the EBs of some DLMAs were enhanced over a bare monopole antenna and an EB characteristic curve has a maximum point. This result suggests the presence of the optimum electrical volume for the dielectric loading in order to obtain the best EB performance. A calculation by the finite-difference time-domain (FDTD) method was also conducted to confirm the presence of the maximum EB value under a certain condition. A general reason for the existence of the peak value is also explained using a mathematical deduction 相似文献
8.
A Study of Shadowing on Indoor Visible-Light Wireless Communication Utilizing Plural White LED Lightings 总被引:3,自引:1,他引:2
Toshihiko Komine Shinichiro Haruyama Masao Nakagawa 《Wireless Personal Communications》2005,34(1-2):211-225
White LED is considered as a strong candidate for the future lighting technology. We have proposed an optical wireless communication
system that employs white LEDs for indoor wireless networks. In this system, LED is used not only as a lighting device, but
also as a communication device. The transmitter has large optical power and large emission characteristics to function as
lighting device. And the system has specific wireless channel impulse response differing from infrared wireless communication.
In this paper, we discuss about shadowing effect on the system utilizing plural LED lightings including the performance of
ISI based on the impulse response. We consider the downlink transmission based on TDMA and evaluate the shadowing effect caused
by pedestrians with computer simulation. When the shadowing often occurs at 800 Mb/s, the performance of outage call duration
rate and blocking rate are improved by using 3 LED lightings compared with 1 or 2 LED lightings. And, we show that the system
with the optimal number of the LED lighting is robust against shadowing and can accommodate more calls.
Toshihiko Komine was born in Shizuoka, Japan, on November 17, 1978. He received the B.E. and M.E. degrees in Information and Computer Science
from Keio University, Yokohama, Japan, in 2001 and 2003 respectively. He is currently studying for the Ph.D. degree at Department
of Information and Computer Science, Keio University. His current research interests are optical wireless communications and
LED communications.
Shinichiro Haruyama is a professor at Department of Information and Computer Science, Faculty of Science and Technology, Keio University, Yokohama,
Japan. He received an M.S. in engineering science from University of California at Berkeley in 1983 and a Ph.D. in computer
science from the University of Texas at Austin in 1990. He worked for Bell Laboratories of AT{&}T and Lucent Technologies,
U.S.A from 1991 to 1996, and for Sony Computer Science Laboratories, Inc. from 1998 to 2002. His research interests include
reconfigurable system, system design automation, wireless communication, and visible light communication.
Masao Nakagawa was born in Tokyo, Japan in 1946. He received the B.E., M.E. and Ph.D. degrees in electrical engineering from Keio University,
Yokohama, Japan, in 1969, 1971 and 1974 respectively. Since 1973, he has been with the Department of Electrical Engineering,
Keio University, where he is now a Professor. His research interests are in CDMA, consumer Communications, Mobile communications,
ITS (Intelligent Transport Systems), Wireless Home Networks, and Visible light Communication. He received 1989 IEEE Consumer
Electronics Society Paper Award, 1999-Fall Best Paper Award in IEEE VTC, IEICE Achievement Award in 2000, IEICE Fellow Award
in 2001. He was the executive committee chairman on International Symposium on Spread Spectrum Techniques and Applications
in 1992 and the technical program committee chairman of ISITA (International Symposium on Spread Spectrum Techniques and Applications)
in 1994. He is an editor of Wireless Personal Communications and was a guest editor of the special issues on “CDMA Networks
I, II, III and IV” published in IEEE JSAC in 1994 (I and II) and 1996 (III and IV). He chairs the Wireless Home Link sub-committee
in MMAC (Multimedia Mobile Access Communication Promotion Committee). 相似文献
9.
The aim of this study was to bring to the surface the strategic use of imitative processes in the context of a 2-route model: (a) direct imitation, used in reproducing new, meaningless actions, and (b) imitation based on stored semantic knowledge of familiar meaningful actions. Three experiments were carried out with healthy participants who reproduced meaningful and meaningless actions within an established time limit. The study investigated 3 factors that could potentially affect the selection of processes used for imitation: (a) the composition of the experimental list (blocked or mixed presentation), (b) the presence-absence of instructions (Experiments 1 and 2), and (c) the relative proportions of the stimuli (Experiment 3). Overall, the results suggest that each of these factors influences the selection of imitative strategies in healthy individuals with temporarily reduced capacities, as happens in the case of brain-damaged patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Yasushi Sobajima Kunihiro Mori Masahiro Tsukamoto Norimitsu Yoshida Masao Takahashi Hikaru Kobayashi Shuichi Nonomura 《Solar Energy Materials & Solar Cells》2005,85(2):240-187
Effects of cyanide (CN) treatment with hydrogenated amorphous silicon (a-Si:H) films have been investigated. The decrease of ΔV/V was observed in cyanide treated a-Si:H films and the successive thermal annealing at 200°C after CN treatment induced the further reduction of the ΔV/V. XPS spectra show the indirect evidence that the cyanide species is present within 10 nm from the hydrogenated amorphous silicon surface. The results of CN treatment with a-Si:H solar cells are demonstrated. 相似文献