Preparation of Collagen‐Glycosaminoglycan Sponges with Open Surface Porous Structures Using Ice Particulate Template Method

Funnel‐like sponges of collagen incorporated with glycosaminoglycan (GAG) were prepared by freeze‐drying using ice particulates as templates. The funnel‐like collagen‐GAG sponges showed similar porous structures to those of funnel‐like collagen sponges. The funnel‐like collagen‐GAG and collagen sponges have one top surface layer and one bulk porous layer. The large, top surface pores were determined by ice particulates that were used as templates, and the inner bulk pores were determined by freezing temperature. The funnel‐like pore structures facilitated homogenous cell distribution, improved cell viability, and resulted in homogenous tissue formation. Incorporation of GAG increased the mechanical property and cell viability of collagen sponges.

     

Electrical switching properties of nanostructured multilayer superlattice Ge–Si…Cu…Si–Ge prepared by electron beam evaporation on glass

In this study, the fabrication of nanostructured multilayer superlattice Ge–Si…Cu…Si–Ge using electron beam evaporation on glass substrates at a temperature of 200 °C has been reported. The structural, optical and electrical characteristics of such films were then studied by means of DC polarization, powder X-ray diffraction (XRD), scanning electron microscopy, atomic force microscopy (AFM), Rutherford backscattering (RBS) and UV–visible spectroscopic techniques. The XRD pattern obtained showed an amorphous state along with some reflected XRD signals from the Ge planes while there were no reflected signals from the Si and Cu layers. The average estimated grain size diameter (_Dav.)$\left(D_{av.}\right)$ is 30.13 nm as found from the XRD experiment using the Debye–Scherrer equation. The grain size as estimated from the AFM images was found to be within 28–31 nm, which is in good agreement with the XRD average value. RBS analysis confirmed the multilayer structure of the superlattice. The optical allowed indirect band gap of the superlattice obtained from the Tauc plot was found to be 1.19 eV, which is greater than that of bulk Ge semiconductor (0.66 eV). This fact indicates that the incorporation of a Cu layer instead of the Ge layer enables us to change the indirect to direct transitions in Ge/Si devices. Current density–voltage (J$J$–V$V$) characteristics of the nanodevice showed an electrical switching effect (VCNR) with the largest ON/OFF current ratio of the order of 10 ⁶ at 15 V.     

Critical Enhancements of MRI Contrast and Hyperthermic Effects by Dopant‐Controlled Magnetic Nanoparticles

Doped up : The incorporation of Zn²⁺ dopants in tetrahedral sites leads to the successful magnetism tuning of spinel metal ferrite nanoparticles (see picture). (Zn_0.4Mn_0.6)Fe₂O₄ nanoparticles exhibit the highest magnetization value among the metal ferrite nanoparticles. Such high magnetism results in the largest MRI contrast effects (r2=860 mm^?1 s^?1) reported to date and also huge hyperthermic effects.

     

Rational Construction of 2D and 3D Borromean Arrayed Organic Crystals by Hydrogen‐Bond‐Directed Self‐Assembly

Borromean organic networks: The rigid and trigonal pyramidal molecule, 1,3,5‐tris(4‐carboxyphenyl)adamantane (TCA), self‐assembles into a 2D Borromean linked network by hydrogen bonds. Different linkers (methanol, phenazine, 4,4′‐bipyridine, and 4,4′‐azopyridine) result in more complex Borromean networks or a 3D polycatenation network.

     

Retrodiction for coherent communication with homodyne or heterodyne detection

Previous work on the retrodictive theory of direct detection is extended to cover the homodyne detection of coherent optical signal states and . The retrodictive input state probabilities are obtained by the application of Bayes' theorem to the corresponding predictive distributions, based on the probability operator measure (POM) elements for the homodyne process. Results are derived for the retrodictive information on the complex amplitude of the signal field obtainable from the difference photocount statistics of both 4-port and 8-port balanced homodyne detection schemes. The local oscillator is usually assumed much stronger than the signal but the case of equal strengths in 4-port detection is also considered. The calculated probability distributions and error rates are illustrated numerically for values of signal and local oscillator strengths that extend from the classical to the quantum regimes.     

Solvent-assisted room-temperature compression molding approach to fabricate porous scaffolds for tissue engineering

This study investigated the room-temperature compression molding/particle leaching approach to fabricate three-dimensional porous scaffolds for tissue engineering. Scaffolds with anatomical shapes (ear, joint, tube, cylinder) were made from biodegradable poly(D,L-lactide) and poly[(D,L-lactide)-co-glycolide]. The utility of this room-temperature compression approach comes from the effect of solvent assistance, but the tendency for post-molding scaffold shrinkage is a problem unique to this method and is thus examined with emphasis in this paper. Scaffold shrinkage was found to be tolerable under normal fabrication conditions with high salt contents, which is just what the preparation of highly porous scaffolds requires. Furthermore, the resultant porosities after salt leaching were measured as well as the initial scaffold shrinkages after solvent evaporation, and the relation between them was revealed by theoretical analysis and confirmed by comparison with experimental measurements. The pores were interconnected, and porosity can exceed 90%. The effects of porosity on the mechanical properties of porous scaffolds were also investigated. This convenient fabrication approach is a prospective method for the tailoring of porous scaffolds for a variety of possible applications in tissue engineering and tissue reconstruction.