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Optimization and Engineering - 相似文献
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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
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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
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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
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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
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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
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Dattoli G. De Angelis A. Gallerano G.P. Mari C. Torre A. 《Quantum Electronics, IEEE Journal of》1991,27(4):903-907
The authors use a simple model of saturation in free-electron lasers operating with pulsed beams to study the intensity growth as a function of the cavity mismatch and of the coupling parameter. In spite of the simplicity of the model, the dependence of the intracavity power, as a function of the cavity detuning, is reproduced remarkably well. It is also pointed out that an enhancement of the optical power is obtained by adjusting the cavity length while the optical signal grows. The problem is analyzed qualitatively and realization schemes are proposed 相似文献