Electrospun nanofibrous scaffolds in neural tissue engineering provide an alternative approach for neural regeneration. Since the topography of a surface affects the microscopic behaviour of material; the creation of nanoscale surface features, which mimic the natural roughness of live tissue, on polymer surfaces can promote an appropriate cell growth and proliferation. In this research, a unique PLGA nanofibrous structure was fabricated without any post-electrospinning treatment. Scaffolds were prepared in two general groups: cylindrical and ribbon-shaped electrospun fibres, with smooth and rough (porous and grooved) surfaces. The experiments about nerve cell culture have demonstrated that the nanoroughness of PLGA electrospun scaffolds can increase the cell growing rate to 50 % in comparison with smooth and conventional electrospun scaffolds. SEM and AFM images and MTT assay results have shown that the roughened cylindrical scaffolds enhance the nerve growth and proliferation compared to smooth and ribbon-shaped nanofibrous scaffolds. A linear interaction has been found between cell proliferation and surface features. This helps to approximate MTT assay results by roughness parameters.

Layered fabric systems with an electrospun nanofiber web layered onto a sandwich of woven fabric were developed to examine the feasibility of developing breathable barrier textile materials. Some parameters of nanofiber mats, including the time of electrospinning and the polymer solution concentration, were designed to change and barrier properties of specimens were compared. Air permeability, water vapor transmission, and water repellency (Bundesmann and hydrostatic pressure tests) were assessed as indications of comfort and barrier performance of different samples. These performances of layered nanofiber fabrics were compared with a well-known water repellent breathable multi-layered fabric (Gortex). Multi-layered electrospun nanofiber mats equipped fabric (MENMEF) showed better performance in windproof property than Gortex fabric. Also, water vapor permeability of MENMEF was in a range of normal woven sport and work clothing. Comparisons of barrier properties of MENMEF and the currently available PTFE coated materials showed that, those properties could be achieved by layered fabric systems with electrospun nanofiber mats.

SUMMARY Statement of the Problem:The color stability of resin cements plays a major role in the esthetic performance of porcelain laminate veneers. Some dual-polymerizable resin cements used to bond porcelain laminates were shown to undergo color changes during service. Some recently produced cements are described as being color stable, but scientific data are not available. Clinical RelevanceWhile the studied cements behaved acceptably according to the color change index (∆E), they functioned differently in regards to opacity, especially the self-cure ones.

A new technology based on the liquid support system is introduced for fabricating continuous twisted nanofibrous yarn. In this novel technique, the electrospun yarn was collected from the top of the water vortex such that it can be twisted simultaneously during yarn production. Our study demonstrated the feasibility of the technique for producing continuous twisted yarn from well aligned nanofibers. It is shown that the system can be modified to have different yarn counts with various twists. Further, significant improvement can be seen in the strength and strain when nanofibrous yarn is twisted compared to non‐twisted yarn. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers

Specific internal pore architectures are required to provide the needed biological and biophysical functions for fibrous scaffolds as these architectures are critical to cell infiltration and in-grows performance. However, the key challenging on evaluating 3D pore structure of fibrous scaffolds for better understanding the capability of different structures for biological application is not well investigated. This article reports a fast, accurate, nondestructive, and comprehensive evaluation approach based on confocal laser scanning microscopy (CLSM) and three-dimensional image analysis to study the pore structure and porosity parameters of Nano/Microfibrous scaffolds. Also a new method of making the fiber fluorescent using quantum dots (QDs) was applied before 3D imaging. Fibrous scaffolds with different porosity parameters produced by electrospinning and their 3D-pore structure was evaluated by this approach and the results were compared to results of capillary flow porometry. The pore structural properties measured in this approach are in good agreement with that measured by the capillary flow porometry (with significant level 0.05). Furthermore, the introduced approach can measure the pore interconnectivity of the scaffold.