Development of topical gel containing aceclofenac-crospovidone solid dispersion by “Quality by Design (QbD)” approach

This article describes the development, optimization, and evaluation of Carbopol 940 topical gel containing aceclofenac-crospovidone (1:4) solid dispersion using “Quality by Design (QbD)” approach based on 2³ factorial design. The effect of crospovidone, tri-ethanolamine, and ethyl alcohol amount on the drug permeation profile of the topical gel containing aceclofenac-crospovidone solid dispersion was optimized by 2³ factorial design. The optimized gel showed improved permeation profile with cumulative drug permeation of 26.262 ± 2.157%, and permeation flux of 0.059 ± 0.011 μg/cm²/h. These gels were characterized by pH, viscosity, gel strength and FTIR study. The in vivo anti-inflammatory activity of the optimized gel was evaluated in rats using carrageenan-induced rat-paw oedema model and found excellent anti-inflammatory comparable with a marketed gel without producing any skin irritation.     

Effect of interface coupling between polarization and magnetization in La0.7Pb0.3MnO3 (LPMO)/P(VDF-TrFE) flexible nanocomposite films

Journal of Materials Science - La0.7Pb0.3MnO3(LPMO) nanoparticles (NPs) were prepared by sol–gel auto-combustion method. These were embedded in P(VDF-TrFE) to form (0–3) nanocomposite...     

AMORE: A World Wide Web image retrieval engine

Search engines are useful because they allow the user to find information of interest from the World Wide Web. However, most of the popular search engines today are textual; they do not allow the user to find images from the Web. This paper describes AMORE, a Web search engine that allows the user to retrieve images from the Web by specifying relevant keywords or a similar image. Text and image search can also be combined. Moreover, we have developed a Query Result Visualization Environment that allows the organization of the results if many images are retrieved. In this paper we present AMORE's user interface and explain the technique for retrieving images visually similar to a user specified image. The method of automatically assigning relevant keywords to the images is then explained. Finally, the architecture of the system as well as some interesting observations of our experiences with AMORE are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

High current efficiency single-stage bulk-driven subthreshold-biased class-AB OTAs with enhanced transconductance and slew rate for large capacitive loads

This paper introduces two high-performance single-stage bulk-driven (BD) operational transconductance amplifiers (OTA) in weak-inversion with rail-to-rail input and output voltage ranges suited for the excessively low-voltage of 0.5 V supply. The strategy depends on adopting a modified bulk-driven non-tailed input core to achieve high input core transconductance with a minimum power supply and an enhanced input common-mode range. Moreover, a partial positive feedback loop provides an overall improved DC gain and effective transconductance further. The input core of OTA1, named composite class-AB OTA, comprises two combined non-tailed differential pairs as composite differential pairs. The proposed OTA2, named composite super class-AB BD-OTA, exploits a matched bulk-input Flipped voltage follower (FVF) pair to adaptively bias the input core used in the composite class-AB BD OTA. As a result, a significant increase in large-signal input current to the output side due to super class-AB behavior improves the slew rate. The post-layout simulation results using the Cadence Spectre simulator with UMC 0.18 µm process technology confirm that the proposed OTAs have improved small-signal and large-signal performances over the conventional OTA driving a high capacitive load of 5 nF. The proposed composite class-AB and super class-AB BD OTA deliver 2.29 times, and 3.77 times open-loop DC gain, 10.6 times, and 117 times unity-gain bandwidth with 2 times, and 12.03 times slew rate at the expense of almost 0.52 times and 1.21 times power consumed over conventional counterpart, respectively.

     

A highly linear CMOS transconductance amplifier in 180?nm process technology

The present article describes the design and analysis of an operational transconductance amplifier (voltage to current converter) with wide linear input range. The proposed configuration combines the techniques of signal attenuation and source degeneration in order to reduce the odd order harmonic distortion significantly. The proposed circuit is compared with several circuit topologies based on MOS differential pairs with respect to their achievable linearity, input referred noise and power consumption. The linear transconductor is designed and simulated in 180?nm CMOS process technology with 1.8?V power supply. Simulation results show third order harmonic distortion (HD ₃) of ?70?dB for 600?mV_pp input signal. For 1% transconductance variation the linear range is about 1.2?V_pp. The input referred noise of the transconductor is $70\,\hbox{nV}/\sqrt{\text {Hz}}$ at 10?MHz. The quiescent power consumption is only 450???W.     

Discovering and Analyzing World Wide Web Collections

With the explosive growth of the World Wide Web, it is becoming increasingly difficult for users to discover Web pages that are relevant to a topic. To address this problem we are developing a system that allows the collection and analysis of Web pages related to a particular topic. In this paper we present the systems overall architecture and introduce the focused crawler used by the system. We also discuss the various techniques we use to allow the user to analyze and gain useful insights about a collection. Finally, we present some statistics on the collections.     

Tuning the BODIPY core for its potential use in DSSC: a quantum chemical approach

Boron dipyrromethene (BODIPY) is a highly promising candidate for use in dye-sensitized solar cell (DSSC), because of its attractive absorption characteristics such as strong extinction coefficients in the visible and near-IR ranges (70000–80000 \(\hbox {M}^{-1}\) \(\hbox {cm}^{-1})\), large quantum yields, longer excited-state lifetime and also high solubility in many organic solvents. Moreover, the absorption peaks can be shifted towards longer wavelengths when functionalized at suitable positions of the BODIPY core. Herein, on the basis of density functional theory (DFT) and time-dependent DFT, we provide the opto-electronic properties of BODIPY core-functionalized dyes to see their applicability in organic DSSC. Our systematic analyses reveal that the 2,6 substituted dyes show better photovoltaic properties compared to the 3,5 substituted ones. On the basis of empirical relationship, we have also calculated the photo-induced electron injection times of some dye-\(\hbox {TiO}_{2}\) composites, which seem to be in the ultrafast time scale, thus rendering them a promising candidate for DSSC applications. Our theoretical studies provide that judiciously designed BODIPY core-derived dyes show certain unique spectroscopic and electronic features that make them highly advantageous in DSSC applications as compared to other organic dyes.     

Usability is more valuable predictor than product personality for product choice in human-product physical interaction

Product personality and product usability are two important factors which can influence consumers' product choice. Published literature are available regarding independent impact of product personality and product usability on product choice but no research has been reported so far for understanding their collective influence on product choice. In addition, which factor between usability and product personality contributing more in product choice is still not clear. Current research thus aimed to bridge these research gaps by establishing inter-relationships among product personality, usability and product choice. To achieve this goal, two separate experiments were conducted. Results of first experiment revealed that products having high product usability also possessed strong product personality. Following second experiment, it was observed that solitary influence of product usability on product choice was more than the standalone influence of product personality in human-product physical interaction. Moreover, it unfolded the fact that product usability mediates the influence of product personality towards product choice. Established interrelationships among product personality, usability and product choice, would help designer and ergonomists to decide how product attributes could be manipulated to enhance product personality and/or product usability to ensure product choice.     

Quinoline–Glycomimetic Conjugates Reducing Lipogenesis and Lipid Accumulation in Hepatocytes

Nonalcoholic fatty liver disease (NAFLD), which is characterized by excess accumulation of triglyceride in hepatocytes, is the major cause of chronic liver disease worldwide and no approved drug is available. The mechanistic target of rapamycin (mTOR) complexes has been implicated in promoting lipogenesis and fat accumulation in the liver, and thus, serve as attractive drug targets. The generation of non‐ or low cytotoxic mTOR inhibitors is required because existing cytotoxic mTOR inhibitors are not useful for NAFLD therapy. New compounds based on the privileged adenosine triphosphate (ATP) site binder quinoline scaffold conjugated to glucose and galactosamine derivatives, which have significantly low cytotoxicity, but strong mTORC1 inhibitory activity at low micromolar concentrations, have been synthesized. These compounds also effectively inhibit the rate of lipogenesis and lipid accumulation in cultured hepatocytes. This is the first report of glycomimetic–quinoline derivatives that reduce lipid load in hepatocytes.