Quantum Size Effects and Transport Phenomena in PbSe Quantum Wells and PbSe/EuS Superlattices

It is established that the room-temperature dependences of transport properties on the total thickness of PbSe layers d in PbSe/EuS superlattices exhibit an oscillatory behavior. It is shown that the oscillation period Δd practically coincides with the period of the thickness oscillations observed earlier in single PbSe/EuS quantum well. The non-monotonic character of these dependences is attributed to quantum size effects. The theoretically estimated and experimentally determined Δd values are in good agreement

Osteoinductive properties of secretome of human mesenchymal stem cells, obtained with automatic cell culture system

The secretome of human mesenchymal stem cells (MSCs) after osteogenic differentiation of FetMSC cells in vitro was obtained to develop tissue engineering technologies for bone tissue. For standard secretome samples a large number of FetMSC cells (7 × 108 cells) were cultured in serum-free conditioned medium (SFCM

Modern approaches to diagnosis and treatment of urethral strictures: literature review and own experience

This article presents a literature review of modern methods of diagnosis and treatment for urethral strictures. In addition, the own results of a pilot study on the use of synthetic tissue-engineering structures as a material for urethroplasty substitution are presented as well

Experimental application of tissue engineered constructions for urethroplasty

Introduction. For diseases such as stricture and obliteration of the urethra, urethral hypospadias, reconstructive operations are required. The buccal mucosa is the material most commonly used for these operations. The search for alternative materials, carried out in order to reduce trauma and complications in the donor area, is an urgent area of modern urology. Tissue engineered constructions (TEC) can be used as such material.Objective. Justification of the possibility of applying a TEC based on the biodegradable polymers and seeded with autologous buccal epithelium (BE) cells as an implantable material for urethroplasty in an experiment.Methods and Materials. TEC based on poly-L-lactide-caprolactone (PLC) and poly-L-lactide-glycolide (PLG) seeded with BCs was created. Rabbits (n=12) underwent a biopsy of the oral mucosa, BCs were isolated, cultured and PLC-PLG scaffold was seeded with cells. TECs seeded with autological BCs were used on the model of acute trauma of rabbit urethra for replacement urethroplasty.Results. The results were evaluated after 12 weeks, according to the histological examination, there was a repair of the urethral mucosa. According to the data of retrograde urethrography, no impaired urethra patency was detected.Conclusion. TEC (PLK-PLG) seeded with autologous BCs ensured the maintenance of the rabbit urethral lumen which is necessary for adequate urination. This TEC could be recommended for the further clinical studies

Anisotropic Microwave Absorption in High-Tc\text{}_{c} like Semiconductor Superconducting Superlattices (001) PbTe-PbS

The anisotropic microwave absorption in the presence of alternative magnetic field has been studied for the first time in superconducting super-lattices based on PbTe-PbS, which are layered anisotropic systems similar to high T$\text{}_{c}$ superconductors. A new method of study has been used. The microwave response was detected under broad-band conditions and compared with the results of synchronous detection. All the features which have been observed in high T$\text{}_{c}$ materials are clearly seen here

Superconductivity of Non-Strained PbTe-PbS and Strained PbTe-SnTe Superlattices

A comparative study of structural and superconductive properties of semi conductor epitaxial superlattices PbTe-SnTe and PbTe-PbS grown on (001) KCl has been carried out. It has been found that the superconductivity of the PbTe-SnTe superlattices is caused by the stretching strain in the SnTe layers and it may be connected with the relative positions of L$\text{}_{8}^{+}$ and L$\text{}_{6}^{+}$ terms of PbTe and SnTe, respectively in the heterojunction. In contrast to the PbTe-SnTe superlattices, the superconductivity of the PbTe-PbS super lattices is found to be associated with regular misfit dislocation grids which are generated at the interfaces