Vignan University

About: Vignan University is a education organization based out in Guntur, Andhra Pradesh, India. It is known for research contribution in the topics: Control theory & CMOS. The organization has 1138 authors who have published 1381 publications receiving 7798 citations.

Synthesis and Antitumor Activity Evaluation of 2-Aminothiazoles Appended 5-methylisoxazoline and Pyridine-piperazine Hybrid Molecules

Abstract: A highly efficient and milder protocol for the syntheses of novel series of 2-aminothiazoles bearing 5-methylisoxazoline and pyridine-piperazine hybrid molecules has been developed. The target compounds 13a-e were screened for their in vitro cytotoxicity activity against various tumor cell lines including MCF-7 (human breast adenocarcinoma), HCT-116 (colorectal carcinoma), Jurkat (human Tcell leukemia) and THP-1 (human acute monocytic leukemia). The bioactive assay showed most of the new compounds exhibited promising results in comparison with the parental Sunitinib. The synthesized compounds could well be used in the future as lead anticancer drugs in drug development studies. The synthesized compounds were fully characterized by IR, 1H NMR, 13C NMR, elemental analysis and mass spectral data.

A low power encoder for a 5-GS/s 5-bit flash ADC

Abstract: A low power high speed encoder is proposed for a 5-GS/s 5-bit flash analogue-to-digital converter (ADC). The designing of a thermometer code to binary code is one of the bottlenecks in achieving high speed. The modus operandi involved in this process is that an encoder circuit translates the thermometer code into the gray code to reduce the effect of meta-stability and reduction of bubble errors. And also that low power and high speed encoder is designed by deploying a new logic design style to implement conversion of the thermometer code to binary code through differential cascade voltage switch logic (DCVSL). However the encoder proposed is designed by using Cadence 180 nm CMOS technology with a supply rail voltage typically ±0.5 V. The simulating results thus obtained is shown for sampling frequency of 5-GS/s and the average power dissipation of 23.29 µW.

Iron Oxide-Cobalt Nanocatalyst for O-tert-Boc Protection and O-Arylation of Phenols.

Abstract: Efficient and general protocols for the O-tert-boc protection and O-arylation of phenols were developed in this paper using a recyclable magnetic Fe3O4-Co3O4 nanocatalyst (Nano-Fe-Co), which is easily accessible via simple wet impregnation techniques in aqueous mediums from inexpensive precursors. The results showed the catalysts were well characterized by XRD (X-ray Diffraction), ICP-AES (Inductive Coupled Plasma Atomic Emission Spectroscopy), TEM (Transmission Electron Microscopy), TOF-SIMS (Time-Of-Flight Secondary Ion Mass Spectrometry) and XPS (X-ray Photoelectron Spectroscopy). The O-tert-boc protection and O-arylation of phenols was accomplished in good to excellent yields (85–95%) and the catalyst was reusable and recyclable with no loss of catalytic activity for at least six repetitions.

Segmentation of Lungs from Chest X Rays Using Firefly Optimized Fuzzy C-Means and Level Set Algorithm

Abstract: Segmentation of lungs from chest x ray is a non trivial task required as a preprocessing step for detection of different diseases like cardiomelagy, tuberculosis, pneumonia High accuracy in segmentation of lung results in high accuracy of detection of diseases from lungs For the past four decades multiple techniques were proposed for automatic segmentation of lungs In this paper, we propose a hybrid segmentation technique based on firefly optimized fuzzy c-means clustering algorithm The output of the fuzzy c-means is given to level set to finalize the segmentation of the lungs The performance of the proposed technique is evaluated using two public chest x ray datasets: JRST and Montgomery County JRST contains 247 chest x-rays and MC dataset contains 138 chest x-rays The Jaccard coefficient for the proposed segmentation technique is 951 which is on par with the state of art segmentation techniques