Microarray Patches: Poking a Hole in the Challenges Faced When Delivering Poorly Soluble Drugs

Poorly soluble drugs constitute more than 60% of currently marketed pharmaceuticals with over two-thirds of promising new chemical entities failing to enter a clinical setting due to solubility issues. Although oral formulations have made some impact, alternative enhancement strategies for administration of such molecules are actively sought. Over the last decade, innovation on a global scale has enabled the expansion of the frontiers of microarray patches (MAPs) further than ever before. Initially designed to load low doses of hydrophilic and potent therapeutic agents, MAPs are now becoming a viable strategy for the immediate and long-acting delivery of poorly soluble drugs through the skin. This together with the advantages of transdermal administration over the oral and parenteral routes, make of MAPs an appealing platform for the development of products with increased patient compliance. Undoubtedly, MAPs will soon become a readily available therapeutic alternative, and experts from academia, industry and regulatory bodies are working together aiming to facilitate the progression of MAPs toward safe and effective clinical use. This review aims to highlight the ability of MAPs to deliver poorly soluble actives, discuss the mechanisms behind in-skin drug absorption, and evaluate the future direction of the field.     

Automatic computer-aided caries detection from dental x-ray images using intelligent level set

Multimedia Tools and Applications - Dental diseases have high risk of affection across the globe and mostly in adult population. The analysis of dental X-ray images has some difficulties in...     

An electrochemical study of the synthesis and properties of multi-walled carbon nanotube/poly ortho aminophenol composites

Composites of multi-walled carbon nanotubes (MWCNTs) and poly ortho aminophenol (POAP) with good uniformity for use as electrodes in electrochemical capacitors were prepared by electropolymerization by using the ionic surfactant as electrolyte, for dispersing CNTs within conducting polymer/carbon nanotube composite films. The capacitance properties were investigated with cyclic voltammetry (CV), discharge tests and ac impedance spectroscopy. The composite electrode shows much higher specific capacitance, better power characteristics and is more promising for application in the capacitor than a pure POAP electrode. The effect and role of MWCNT in the composite electrode are discussed in detail. In comparison with a Ni–POAP/glassy carbon (GC), a Ni–MWCNT–POAP/GC electrode shows a better catalytic performance for the electrocatalytic oxidation of methanol.     

The oxide electrochemistry of ruthenium and its relevance to trench liner applications in damascene copper plating

There is considerable interest in the use of ruthenium as an ultrathin trench liner in damascene copper plating used to fabricate on-chip interconnects. The problem is that when freshly deposited ruthenium films are exposed to air, their surfaces tend to undergo spontaneous oxidation, and such deposits (as demonstrated here) are reluctant to undergo reduction. Copper deposition in an acid plating bath occurs readily on the oxidized ruthenium, but the presence of oxide is known to have a detrimental effect both on the copper superfilling process and copper adhesion at the Ru/Cu interface.     

A 5th-order ΣΔ modulator with combination of op-Amp and CBSC circuit for ADSL applications

In this letter, a 5th-Order single-loop low distortion Sigma–Delta Modulator (SDM) is implemented with the combination of the comparator-based switched-capacitor (CBSC)-based and op-amp-based techniques for asymmetric digital subscriber line (ADSL) applications. This structure, which uses integrator (CBSC-based) and IIR filter (op-amp-based) concurrently, has relatively fewer feed-forward paths and modulator coefficients for sensitivity reduction to mismatch. To lower the power consumption of the modulator, the integrators are implemented with CBSC, the IIR filter block is implemented by single OTA, and a passive adder is used to realize the adder at the input of the 5-bit quantizer. The design purpose is minimizing the power consumption while the dynamic performance maintains high. As shown in the simulation result, for a 2-MHz signal bandwidth, the modulator achieves a dynamic range (DR) of 86.5 dB and a peak signal-to-noise and distortion ratio (SNDR) of 85 dB with an oversampling ratio of 8. In addition it consumes 18.75 mW from a 1.8-V power supply at 32 MS/s, which obtains a figure of merit of 1.6e−3.     

Simultaneous effects of polymer concentration,jet-stretching,and hot-drawing on microstructural development of wet-spun poly(acrylonitrile) fibers

Investigation of structural development of acrylic fibers during the early stages of the wet-spinning process has great importance both in carbon fiber and textile industries. The simultaneous effects of increasing polymer concentration, jet-stretching and hot-drawing on porosity, morphology, and mechanical properties of wet-spun poly(acrylonitrile) fibers were studied. The detailed microstructure of the voids was characterized by electron microscopy, porosimetry, and thermoporometry. The effects of jet-stretching/hot-drawing on the overall porosity of the fibers were negligible below a threshold polymer concentration. Increasing polymer concentration from 10 to 20 vol.% reduced the total porosity. Hot-drawing was more effective in reducing the overall porosity of the fibers in comparison with jet-stretching. Stretching and drawing replaced the macrovoids by dense ligaments but did not change the volume fraction of nanovoids, however, shifted nanovoids size distribution toward smaller values. In general, Young’s modulus and elongation at break increased by decreasing overall porosity, however, they depended also on the distribution of voids size and chain orientation along the fiber axis. Strength–diameter correlation showed a good agreement with the Griffith’s theory.     

Synthesis of B4C-Nano TiB2 Composite Powder by Sol-Gel Method

Production of (B₄C-nano TiB₂) composite powder by chemical method was evaluated in this study. Starting materials were boron carbide, carbon, and titanium (IV) iso propoxide (TTIP). Water was used as a hydrolyser agent. TTIP was hydrolyzed with water and, consequently, amorphous Ti(OH)₄ was formed. Heat-treatment of Ti(OH)₄ at 100 and 850 °C led to the production of TiO₂ and TiB₂ phases, respectively. The effect of heat-treatment time and temperature on the phase transformation and size of the produced nano powder were investigated. The produced nano powder was characterized by XRD, SEM, and DTA. It was found that heat-treatment time and temperature have significant effects on the amount and size of the produced TiB₂ powder. The data also reveal that the minimum temperature for TiB₂ formation is 650 °C.     

A mathematical model for prediction of microporosity in aluminum alloy A356

In the present work, a mathematical model was developed based on finite difference method to predict the microporosity distribution in A356 aluminum alloy casting. Heat, mass, and gas conservation equations were solved in this model. Moreover, Darcy’s equation was considered in the mushy zone. Results show that the distribution and concentration of microporosities in cast parts vary with both cooling rate and initial gas content. Simulation results were compared with experimental data where proportionally good agreement with experimental results was found. Finally, a complex cast part was simulated presenting the ability of the model to predict the porosities in industrial cast parts.