The glass transition and crystallization kinetic studies on BaNaB9O15 glasses

Transparent glasses of BaNaB9O15 (BNBO) were fabricated via the conventional melt-quenching technique. The amorphous and the glassy nature of the as-quenched samples were respectively, confirmed by X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC). The glass transition and crystallization parameters were evaluated under non-isothermal conditions using DSC. The correlation between the heating rate dependent glass transition and the crystallization temperatures was discussed and deduced the Kauzmann temperature for BNBO glass-plates and powdered samples. The values of the Kauzmann temperature for the plates and powdered samples were 776 K and 768 K, respectively. Approximation-free method was used to evaluate the crystallization kinetic parameters for the BNBO glass samples. The effect of the sample thickness on the crystallization kinetics of BNBO glasses was also investigated.Comment: 23 pages, 12 figure

Atomic scale friction studies on single crystal GaAs using AFM and molecular dynamics simulation

This paper provides a fresh perspective and new insights on the nanoscale friction investigated using molecular dynamics simulation and atomic force microscope (AFM) nanoscratch experiments. The work considered Gallium Arsenide, an important III-V direct bandgap semiconductor material residing in the zinc-blende structure as a reference sample material due to its growing usage in 5G communication devices. In the simulations, the scratch depth was tested as a variable in the fine range of 0.5 nm to 3 nm to understand the behaviour of material removal as well as to gain insights into the nanoscale friction. Scratch force, normal force and average cutting forces were extracted from the simulation to obtain two scalar quantities namely, the scratch cutting energy (defined as the work done in removing a unit volume of material) and kinetic coefficient of friction (defined as the force ratio). A strong size effect was observed for scratch depths below 2 nanometres from the MD simulations and about 15 nm from the AFM experiments. A strong quantitative corroboration was obtained between the MD simulations and the AFM experiments in the specific scratch energy and more qualitative corroboration with the pile up and the kinetic coefficient of friction. This conclusion suggested that the specific scratch energy is insensitive to the tool geometry and the speed of scratch used in this investigation but the pile up and kinetic coefficient of friction are dependent on the geometry of the tool tip

Formulation and Evaluation of Galantamine Hydrobromide Proniosome Gel for Alzheimer’s disease

Galantamine hydrobromide is formulated in tablets and capsules prescribed through oral delivery for the treatment of Alzheimer’s disease. However, oral delivery of drugs can cause severe side effects such as nausea, vomiting, and gastrointestinal disturbance. In the present research work, Galantamine hydrobromide is formulated as proniosome gel by Coacervation phase separation method using different surfactants such as Tweens and Spans. Overall eight formulations were developed and evaluated for various parameters. The prepared gels were viewed by naked eye to observe the colour of gel. Microscopical observations of the gels showed vesicles of optimum size from 3.030 mm (P2) - 3.735 mm (P5). The gel also showed optimum rate of spontaneity in the range 9.60 mm3x1000 (P7) to 11.80 mm3x1000 (P4) and entrapment efficiency of vesicles in the range 66.15% (P5) to 86.92% (P3). The gels had pH in suitable range of skin (5.92-6.9). The in vitro drug diffusion studies revealed that the drug diffusion was affected by the various surfactants used. The rank order of surfactant effect on in-vitro drug diffusion was Tween 80 > Tween 60 > Tween 40 >Tween 20 > Span 80 > Span 60 > Span 40 > Span 20. The proniosomal gel containing Tween 80 showed maximum drug diffusion (99.24%) and the gel containing Span 20 showed minimum drug diffusion (71.74%). FT-IR studies of optimized proniosome gel P8 revealed the absence of any chemical interactions between drug and carriers used. Keywords: Galantamine hydrobromide, Proniosome gel, Coacervation phase separation method,   Surfactants, in vitro drug diffusion studies

Ultrasound Image Denoising using Multiscale Ridgelet Transform with Hard and NeighCoeff Thresholding

Ultrasound imaging utilizes sound waves reflected from different organs of the body to give local details and important diagnostic information on the human body. However, using ultrasound images for diagnosis is difficult because of the existence of speckle noise in the image. The speckle noise is due to interference between coherent waves which are backscattered by targeted surfaces and arrive out of phase at the sensor. This hampers the perception and the extraction of fine details from the image. Speckle reduction/filtering i.e. visual enhancement techniques are used for enhancing the visual quality of the images. The multscale ridgelet transform based denoising algorithm for Ultrasound images is proposed for effective edge preservation in comparison to filtering techniques using the Adaptive Filters

Budget feasible mechanisms on matroids

Motivated by many practical applications, in this paper we study budget feasible mechanisms where the goal is to procure independent sets from matroids. More specifically, we are given a matroid =(,) where each ground (indivisible) element is a selfish agent. The cost of each element (i.e., for selling the item or performing a service) is only known to the element itself. There is a buyer with a budget having additive valuations over the set of elements E. The goal is to design an incentive compatible (truthful) budget feasible mechanism which procures an independent set of the matroid under the given budget that yields the largest value possible to the buyer. Our result is a deterministic, polynomial-time, individually rational, truthful and budget feasible mechanism with 4-approximation to the optimal independent set. Then, we extend our mechanism to the setting of matroid intersections in which the goal is to procure common independent sets from multiple matroids. We show that, given a polynomial time deterministic blackbox that returns -approximation solutions to the matroid intersection problem, there exists a deterministic, polynomial time, individually rational, truthful and budget feasible mechanism with (3+1) -approximation to the optimal common independent set

Urinary bladder melanosis with complete resolution case report

Background Melanosis of the bladder is a rare condition characterized by multifocal, diffuse melanin pigmentation of the urothelial mucosa or lamina propria without any proliferation of melanocytes. Less than 25 cases have been reported so far of which only four patients had concurrent urothelial carcinoma. Case presentation We are reporting a case of melanosis of the bladder in a 58-year-old female associated with pTaG1 transitional urothelial cell carcinoma (TCC) of the bladder who presented with symptoms of recurrent urinary tract infection (UTI). Cystoscopy and biopsy results confirmed benign melanosis. Conclusion Our case is unique because bladder melanosis associated low grade TCC with complete resolution of both conditions within one year

Wealth distribution in an ancient Egyptian society

Modern excavations yielded a distribution of the house areas in the ancient Egyptian city Akhetaten, which was populated for a short period during the 14th century BC. Assuming that the house area is a measure of the wealth of its inhabitants allows us to make a comparison of the wealth distributions in ancient and modern societies