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441.
Monitoring complex biological assays such as in vitro protein synthesis over long periods in micrometer-sized cavities of poly(dimethyl siloxane) (PDMS) microfluidic devices requires a strategy that solves the adsorption and absorption problems on PDMS surfaces. In this study, we developed a technique that instantaneously arrays aqueous microdroplets coated with a phospholipid membrane within a single microfluidic device. The simple lipid bilayer coating effectively inhibits the adsorption of proteins and DNA, whereas the encapsulation of the droplet reduces the area in contact with the PDMS surface, resulting in decreased absorption in part. Although the size becomes smaller during the first few hours, a lipid-coated microdroplet array demonstrated a temporal stability of more than 20 h and a size uniformity of CV 3% in the device. Furthermore, we succeeded in expressing a green fluorescent protein by confining an in vitro translation system in the microdroplets, which was confirmed by scanning the fluorescence spectrum of the droplets, demonstrating that the lipid coat secured the synthetic reaction from the adsorption problem. 相似文献
442.
Ogata T Kudo S Watanabe Y Muramatsu T Yamamoto H Iwai S Takagi S Harano H Matsumoto T Nishiyama J 《Radiation protection dosimetry》2011,146(1-3):107-110
Bonner sphere spectrometer (BSS) is used in radiation protection measurement because of its wide energy range (thermal to MeV) and easy operation. Mitsubishi Heavy Industries (MHI) has used BSS to obtain neutron spectrum and has used the neutron spectrum to estimate neutron dose or induced activity. Calibration of BSS is important to estimate precise neutron dose or induced activity. MHI BSS was calibrated at National Institute of Advanced Industrial Science and Technology (AIST). The calibration results at AIST are in good agreement with calculation results. 相似文献
443.
针对GPS卫星信号在楼群密集的城市和室内存在定位盲区而无法单独完成定位的难题,提出GPS-DTMB组合导航定位方法。在多源信号组合导航定位系统中,为了解决导航定位精度与运算复杂度间的矛盾,研究改进的加权行列式选星算法在GPS与DTMB组合定位系统中的可行性,与传统最小GDOP选星算法相比较,改进的选星算法具有运算复杂度低、计算消耗时间短的优点,并且对比分析在不同的组合卫星数目中,该算法与直接利用传统最小GDOP选星算法相比较的偏差大小,仿真表明,在15种组合卫星中,偏差小于0.1的概率在90%左右,能够得到满意的性能,证明了此方法的实用性。 相似文献
444.
Analytic Self-Consistent Condensates in Quasi-1D Superfluid Fermi Gases in the Andreev Approximation
Giacomo Marmorini Ryosuke Yoshii Shunji Tsuchiya Muneto Nitta 《Journal of Low Temperature Physics》2014,175(1-2):420-426
We present an analytic method to approach Eilenberger equation and the associated Bogoliubov–de Gennes equation for quasi-1D fermionic gases. The problem of finding self-consistent inhomogeneous condensates is reduced to solving a certain class of nonlinear Schrödinger equations, whose most general solitonic solution is indeed available. Previously known solutions can be retrieved by taking appropriate limits in the parameters. The applicability of the method extends to systems with population imbalance and subject to external potential. In particular we show that fermionic zero-modes are robust against population imbalance. 相似文献
445.
446.
In order to reveal the role of disulfide (S‐S) bonds in the fine structure of human hair fibers, especially in the complex between intermediate filaments (IFs) and intermediate filament‐associated proteins (IFAP), we investigated the relationship between melting behavior of (‐crystallites on thermal analysis and structural orientation of the fibers when S‐S bonds were oxidized using 1.5 wt% peracetic acid (PAA) solution. It was revealed that oxidative treatment of human hair fibers immersed in PAA solution made cystine residues dissociate to cysteic acids and that the (‐crystalline structure of the oxidized hair fibers was maintained despite the fission of S‐S bonds. Their thermographs in water on high pressure differential scanning calorimetry (HPD‐SC) showed that the endothermic peak assigned as the melting of (‐crystallites became separated into two endothermic peaks with progression of the treatment time, and the one started melting at a lower temperature while the other had a higher melting temperature than the melting temperature of untreated hair. Furthermore, the sum of the two endothermic peak areas decreased. Polarized light microscopic observation indicated that the orientation of IFAP still existed at the temperature at which the orientation of IFs disappeared. Therefore, these results suggested that some S‐S linkages at the interface between IFs and IFAP dissociated with the PAA treatment and that there was not only some region of IFs stabilized by S‐S bonds but also another region of IFs stabilized by hydrophobic interaction for their thermostability. Keywords: human hair fiber, peracetic acid, disulfide bonds, intermediate filament, (‐crystallites, thermostability, high pressure differential scanning calorimetry, polarized light microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy 相似文献
447.