The effect of conjugating RGD into 3D alginate hydrogels on adipogenic differentiation of human adipose-derived stromal cells

The effects of RGD peptide conjugation to alginate hydrogel on the adipogenic differentiation of ASCs was investigated. After 3 d of culture, RGD-modified alginate hydrogels significantly stimulated FAK and integrin α1 gene expressions and vinculin expression in ASCs. In addition, RGD-modified alginate hydrogels significantly enhanced the adipogenic differentiation of human ASCs to exhibit higher expression levels of oil red O staining and adipogenic genes compared to those of the control group (unmodified gels). These results suggest potential applications of RGD-modified alginate gels for adipose tissue regeneration.     

The synthesis of silica and silica-ceria, core-shell nanoparticles in a water-in-oil (W/O) microemulsion composed of heptane and water with the binary surfactants AOT and NP-5

In a previous work [1] we showed that the swelling behavior of carboxylated core-shell particles (PS-PC) can be modified using a specific sample preparation route or favoring the hydrophobic attractive interaction by other way, i.e. controlling the temperature. In that paper, we found that the swelling was promoted in those particles which were initially in a highly swollen state (pH?10) while it was hindered for those particles which were not previously in this trigger pH. In this work, we present a discussion of the salt-induced swelling of the same carboxylated core-shell system (PS-PC) with two tuned swelling behaviors: the former, called A-2, exhibits promoted swelling while in the latter, called B-1, the swelling is greatly suppressed because of a compact conformation of the polymer shell is induced [1]. Good agreement between experimental, numerical and theoretical results at all pH values is obtained for promoted particles (A-2). On the other hand, the salt-induced swelling behaviors shown by hindered particles (B-1) corroborate that polymer restructuring includes assembly among ionic groups which affect their ionization degree and also the electrosteric interaction between particles. Finally, the salt-induced swelling behavior shown by the B-1 system at pH 8.6 resembles the Pincus regime predicted by scaling theory.     

On a Stochastic Survival Model for a System Under Randomly Variable Environment

In many cases, the survival probability of a system depends not only on the intrinsic characteristic of the system itself but also on the randomly variable external environment under which the system is being operated. In this paper we study a stochastic survival model for a system under random shock process which affects the survival of the system in a complicated way. The lifetime distribution of the system is derived, and the effect of environmental factors on the failure process of the system is also investigated.     

铋系超导体反常晶格膨胀X射线衍射研究

本文利用变温X射线衍射方法研究了室温至液氮温度区间铋系超导体晶格热膨胀与畸变特性.在从正常态向超导态转变过程中,铋系2223相和2212相均在高温区和低温区发生反常热膨胀.发生在超导转变前的晶格反常热膨胀与Mossbauer谱和超声内耗测量得到晶格软化温度相对应,这种结构上的反常行为是超导转变的前驱效应.     

Photoluminescence Study of Functionalized Polysiloxane Gel

Photoluminescence of a polysiloxane gel film incorporating a partially conjugated copolymer polyether-polyphenylenevinylene (PEPPV) has been studied and compared with results obtained from bulk and vacuum evaporated films of the same starting material. The evaporation clearly affects the distribution of lengths of the conjugated parts, yet the incorporation in the gel matrix induces only slight changes in the spectroscopic properties of the polymer.     

Mössbauer analysis on the magnetic properties of Fe–Co nanoparticles synthesized by chemical vapor condensation process

The magnetic properties of Fe–Co nanoparticles synthesized by chemical vapor condensation (CVC) process were investigated. Effect of CVC processing variables on the magnetic properties was analyzed in detail, using Mössbauer spectroscopy, XRD, BET and HRTEM. The synthesized particles were nearly spherical, and their surfaces were identified to be -FeOOH, γ-FeOOH and Fe₃O₄, but not -Fe₂O₃. The magnetic properties were strongly influenced by CVC processing parameters. The increase of cobalt content had changed the magnetic property of the sample. However, when the decomposition temperature and the oxygen content in the carrier gas (Ar) were increased, the magnetic property reduced with decreasing the average particle size. Increasing the vacuum pressure in the chamber resulted in that the magnetic field reinforced with the increase of average particle size.     

高功率激光稳定腔选模分析

讨论了在有限菲涅耳数时，稳定凹－凸腔的高功率激光选模特性，研究表明当稳定凹－凸腔工作在临近界稳区时，基模体积显著提高，具有良好的选模效果。     

Single-path interferometer for measuring fluid flows in real time with low-quality optics

An interferometric concept based on a modified version of the Fabry–Perot interferometry is proposed for measuring flow fields in real-time and some results are presented for demonstration. Being based on a single-path configuration of interfering beams, it is very convenient to build a simple compact measurement system. While allowing the deployment of low-quality optics including test-section windows through compensation of system errors, it is also immune to external vibration. In addition, it can easily allow large aperture and long pathlength of probing beams with good precision. These aforementioned features are very appropriate for measuring large flow fields including wind tunnel testing as well as conducting laboratory experiments without elaborate equipment.