Iron oxide nanoparticles fabricated by electric explosion of wire: Focus on magnetic nanofluids

Nanoparticles of iron oxides (MNPs) were prepared using the electric explosion of wire technique (EEW). The main focus was on the fabrication of de-aggregated spherical nanoparticles with a narrow size distribution. According to XRD the major crystalline phase was magnetite with an average diameter of MNPs, depending on the fraction. Further separation of air-dry EEW nanoparticles was performed in aqueous suspensions. In order to provide the stability of magnetite suspension in water, we found the optimum concentration of the electrostatic stabilizer (sodium citrate and optimum pH level) based on zeta-potential measurements. The stable suspensions still contained a substantial fraction of aggregates which were disintegrated by the excessive ultrasound treatment. The separation of the large particles out of the suspension was performed by centrifuging. The structural features, magnetic properties and microwave absorption of MNPs and their aqueous solutions confirm that we were able to obtain an ensemble in which the magnetic contributions come from the spherical MNPs. The particle size distribution in fractionated samples was narrow and they showed a similar behaviour to that expected of the superparamagnetic ensemble. Maximum obtained concentration was as high as 5 % of magnetic material (by weight). Designed assembly of de-aggregated nanoparticles is an example of on-purpose developed magnetic nanofluid. Copyright © 2012 Author(s)

Glucosamine HCl-based solid dispersions to enhance the biopharmaceutical properties of acyclovir

The objective of the work presented here was to assess the feasibility of using glucosamine HCl as a solid-dispersion (SD) carrier to enhance the biopharmaceutical properties of a BCS class III/IV drug, acyclovir (ACV). The solid-dispersions of acyclovir and glucosamine HCl were prepared by an ethanol-based solvent evaporation method. The prepared formulations characterized by photomicroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transforms infrared spectrophotometry (FTIR), powder x-ray diffractometry (PXRD) and drug content analysis. The functional characterization of ACV-SD was performed by aqueous solubility evaluation, dissolution studies, fasted versus fed state dissolution comparison, ex vivo permeability, and stability studies. Photomicroscopy and SEM analysis showed different surface morphologies for pure ACV, glucosamine HCl and ACV-SD. The physical-chemical characterization studies supported the formation of ACV-SD. A 12-fold enhancement in the aqueous solubility of ACV was observed in the prepared solid dispersions, compared to pure ACV. Results from in vitro dissolution demonstrated a significant increase in the rate and extent of ACV dissolution from the prepared ACV-SD formulations, compared to pure ACV. The rate and extent of ACV permeability across everted rat intestinal membrane were also found to be significantly increased in the ACV-SD formulations. Under fed conditions, the rate and extent of the in vitro dissolution of ACV from the formulation was appreciably greater compared to fasted conditions. Overall, the results from the study suggest the feasibility of utilizing glucosamine HCl as a solid dispersion carrier/excipient for enhancement of biopharmaceutical properties of acyclovir, and similar drugs with low solubility/permeability characteristics

Watermarking Based Image Authentication for Secure Color Image Retrieval in Large Scale Image Databases

An important facet of traditional retrieval models is that they retrieve images and videos and consider their content and context reliable. Nevertheless, this consideration is no longer valid since they can be faked for many reasons and at different degrees thanks to powerful multimedia manipulation software. Our goal is to investigate new ways detecting possible fake in social network platforms. In this paper, we propose an approach that assets identification faked images by combining standard content-based image retrieval (CBIR) techniques and watermarking. We have prepared the wartermarked image database of all images using LSB based watermarking. Using gabor features and trained KNN, user is able to retrieve the matching query image. The retrieved image is authenticated by extracting the watermark and matching it again with the test image

Electrochemical evaluation and phase-related impedance studies on silicon–few layer graphene (FLG) composite electrode systems

Silicon-Few Layer Graphene (Si-FLG) composite electrodes are investigated using a scalable electrode manufacturing method. A comprehensive study on the electrochemical performance and the impedance response is measured using electrochemical impedance spectroscopy. The study demonstrates that the incorporation of few-layer graphene (FLG) results in significant improvement in terms of cyclability, electrode resistance and diffusion properties. Additionally, the diffusion impedance responses that occur during the phase changes in silicon is elucidated through Staircase Potentio Electrochemical Impedance Spectroscopy (SPEIS): a more comprehensive and straightforward approach than previous state-of-charge based diffusion studies

Review of Watermarking and Color Image Retrieval

The development of information technology and network technology is increasing rapidly. In network technology, multimedia communication applications are used in various formats such as text, image, audio and video. These formats are spreading very fast over the internet without any security and they can be easily copied by anyone without any prior protection and their feature can be easily copied. Nowadays the copyright infringement and piracy become very serious problem. Because of this problem, watermarking technology is used to protect the color image. In a recent year, several watermarking techniques are available such as spatial watermarking technique and frequency based watermarking technique. Frequency watermarking technique is used to differentiate the transformation of the wave and the discrete cosine transformation but transform watermarking techniques cannot provide adequate protection of image or data. This provides a weak answer to the problem of geometrical attack such as noise attack, rotation attack and translation attack. Therefore the use of spatial watermarking technique is recommended through the use of least significant bits, patch work and coding to reduce the problem of geometrical attack. This technique is comparatively simple. It can survive simple operations such as cutting and adding noise. In this document, we propose the watermark scheme based on spatial domain for color images. This scheme uses the Sobel and Canny edge detection methods to determine border information of the Luminance and chrominance components of the color image

Image Segmentation and Classification for Medical Image Processing

Segmentation and labeling remains the weakest step in many medical vision applications. This paper illustrates an approach based on watershed transform which are designed to solve typical problems encountered in various applications, and which are controllable through adaptation of their parameters. Two of these modules are presented: the lung cancer detection, a method for the segmentation of cancer regions from CT images, a watershed algorithm for image segmentation and brain tumor detection from MRI images. Various GLCM features along with some statistical features are used for classification using Neural network and Support Vector Machine (SVM). We describe the principles of the algorithms and illustrate their generic properties by discussing the results of both applications in 2D MRI images of Brain tumor and CT images of lung cancer

Image Processing for Medical Image Analysis: A Review

Image processing techniques are used widely in medical areas for improving the image in earlier detection and treatment stages, it is very important to discover the abnormality issues in given images, specially in various cancer, tumours such as lung cancer, breast cancer, etc. Image quality and accuracy is the main factors of this work, image quality improvement and assessment are depending on the enhancement stage where pre-processing techniques is used. The principal objectives of this course are to provide basic introduction and techniques for medical image processing and to promote for further study and research in medical image processing

Mobile satellite service in the United States

Mobile satellite service (MSS) has been under development in the United States for more than two decades. The service will soon be provided on a commercial basis by a consortium of eight U.S. companies called the American Mobile Satellite Consortium (AMSC). AMSC will build a three-satellite MSS system that will offer superior performance, reliability and cost effectiveness for organizations requiring mobile communications across the U.S. The development and operation of MSS in North America is being coordinated with Telesat Canada and Mexico. AMSC expects NASA to provide launch services in exchange for capacity on the first AMSC satellite for MSAT-X activities and for government demonstrations

Study of cervical pap smears in a tertiary care hospital of south Gujarat, India

Background: In India cervical cancer is the leading cause of morbidity and mortality. Cancer of cervix is preventable, and can be diagnosed at the pre-malignant/pre-invasive stage with adequate and repetitive cytological screening by Papanicolaou (Pap) smears.  Methods: The prospective study includes total 1425 patients who were presented with various gynecological problems. Samples were taken and prepared smear were stained with PAP stain. Reporting was carried out by two independent cytopathologist as per Bethesda system.Results: Total 1425 patients were screened; there were 1034 (72.56%) abnormal Pap smears, with 354 (24.84%) normal cases and 37 (2.59%) unsatisfactory or inadequate samples. Total 27 (1.89%) cases showed epithelial cell abnormalities. ASCUS was the most commonly found (40.74%) epithelial cell abnormality out of 27 cases.Conclusions: Incidence of invasive cervical malignancy can be prevented if Pap screening program is effectively implemented in target population