Application of polymeric nanofibers in medical designs,part IV: Drug and biological materials delivery

Nanotechnology has potential applications in different sciences, especially in the biological sciences and medicine. The development of nanofibers has greatly enhanced the scope for fabricating designs that can potentially use in medical sciences. Nanofibers mimic the porous topography of natural extracellular matrix, and are advantageous for tissue regeneration and also sustained release of encapsulated drug or growth factor. In part IV the author summarizes the currently available applications of nanofibers in drug and biological materials delivery.     

Application of polymeric nanofibers in medical designs,part I: Skin and eye

Nanotechnology has wide applications in many fields, especially in the biological sciences and medicine. Nanomaterials are applied as potential materials for treatment and diagnosis. The development of nanofibers has greatly enhanced the scope for fabricating designs that can be potentially used in medical sciences. The application of polymeric nanofibers in biomaterials sciences and tissue engineering review in four sections: skin and eye, neural and cardiovascular tissues, musculoskeletal and urological tissues, drug and biological materials’ delivery. The present review summarizes the currently available applications of nanofibers in skin and eye tissues.     

Algorithms for Handoff Minimization in Wireless Networks

Journal of Computer Science and Technology - This study focuses on the problem of handoff minimization for a set of users moving in a wireless network. This problem is analyzed by considering two...     

Multiple human 3D pose estimation from multiview images

Multimedia Tools and Applications - Multiple human 3D pose estimation is a challenging task. It is mainly because of large variations in the scale and pose of humans, fast motions, multiple persons...     

A low power reconfigurable multi-mode continuous time Delta Sigma modulator for seven different mobile standards with VCO-based quantizer

In this research a novel low power multi-mode continuous time Delta Sigma modulator was designed to be compatible with many mobile wireless standards. This modulator has a reconfigurable structure to adapt to various standards from 0.2 to 20 MHz. The designed modulator uses a VCO-based quantizer not only for lowering power consumption, but also for reducing the required chip area. The presented modulator can function with up to third order of noise shaping, or in a low power mode in which the loop filter is disabled and only the VCO-based quantizer is used. The proposed modulator was implemented and simulated in transistor level in 180 nm technology. This modulator can digitize at least seven standards (LTE (20 MHz)/WLAN/LTE (9 MHz)/WCDMA/UMTS/Bluetooth/GSM) with a favorable dynamic range (65–89 dB) and power consumption (9.1 mW–670 μW).     

Plasmonic Color Filters as Dual‐State Nanopixels for High‐Density Microimage Encoding

Plasmonic color filtering has provided a range of new techniques for “printing” images at resolutions beyond the diffraction‐limit, significantly improving upon what can be achieved using traditional, dye‐based filtering methods. Here, a new approach to high‐density data encoding is demonstrated using full color, dual‐state plasmonic nanopixels, doubling the amount of information that can be stored in a unit‐area. This technique is used to encode two data sets into a single set of pixels for the first time, generating vivid, near‐full sRGB (standard Red Green Blue color space)color images and codes with polarization‐switchable information states. Using a standard optical microscope, the smallest “unit” that can be read relates to 2 × 2 nanopixels (370 nm × 370 nm). As a result, dual‐state nanopixels may prove significant for long‐term, high‐resolution optical image encoding, and counterfeit‐prevention measures.     

Mineralogical and sink-float studies of Jajarm low-grade bauxite

Jajarm's bauxite deposits are mainly diasporic,and they have a low mass ratio of Al2O3/SiO2. It is necessary to increase the run-of-mine mass ratio before feeding the material to the Bayer process. Chemical analysis indicated that the low-grade bauxite sample from Jajarm contained 43.9wt% Al2O3 and 13.35wt% SiO2, resulting in a mass ratio of 3.29. According to mineralogical studies, the presence of aluminosilicate minerals such as kaolinite, illite, and quartz was the main reason for the decrease of the mas...     

Fabrication of superhydrophobic and antibacterial surface on cotton fabric by doped silica-based sols with nanoparticles of copper

The study discussed the synthesis of silica sol using the sol-gel method, doped with two different amounts of Cu nanoparticles. Cotton fabric samples were impregnated by the prepared sols and then dried and cured. To block hydroxyl groups, some samples were also treated with hexadecyltrimethoxysilane. The average particle size of colloidal silica nanoparticles were measured by the particle size analyzer. The morphology, roughness, and hydrophobic properties of the surface fabricated on cotton samples were analyzed and compared via the scanning electron microscopy, the transmission electron microscopy, the scanning probe microscopy, with static water contact angle (SWC), and water shedding angle measurements. Furthermore, the antibacterial efficiency of samples was quantitatively evaluated using AATCC 100 method. The addition of 0.5% (wt/wt) Cu into silica sol caused the silica nanoparticles to agglomerate in more grape-like clusters on cotton fabrics. Such fabricated surface revealed the highest value of SWC (155° for a 10-μl droplet) due to air trapping capability of its inclined structure. However, the presence of higher amounts of Cu nanoparticles (2% wt/wt) in silica sol resulted in the most slippery smooth surface on cotton fabrics. All fabricated surfaces containing Cu nanoparticles showed the perfect antibacterial activity against both of gram-negative and gram-positive bacteria.     

Anomalous first normal stress difference behavior of polymer nanocomposites and liquid crystalline polymer composites

The first normal stress difference (N₁) behavior of polymer nanocomposites and liquid crystalline polymer (LCP) composites is a measure of elasticity and is affected by shear stress as a result of morphological alterations at the molecular and nanostructure levels. In this study, the steady shear rheological behaviors of polylactide (PLA) and nanographite platelet (NGP) bionanocomposites containing 1, 2, 3, and 5 wt% nanofiller were investigated. The shear rheological properties of glass fiber‐filled LCPs (filler aspect ratio > 100) were also examined. One of the objectives of this study was to obtain a correlation between N₁, filler contents, and shear stress/rate of the measurements. The results suggest that N₁ in PLA/NGP bionanocomposites is dependent on the level of filler loading as well as the shear rate beyond a critical value. For the LCP systems, N₁ is positive for the unfilled and negative for the glass fiber‐filled LCPs, respectively. A novel rectangular hyperbola model was successfully developed and utilized to fit the N₁ data of the neat PLA and PLA/NGP composites as well as the unfilled LCPs. The anomalous N₁ behavior of PLA/NGP and LCP composites was also thoroughly discussed in this study. POLYM. ENG. SCI., 54:1300–1312, 2014. © 2013 Society of Plastics Engineers