Design and Analysis of Current Mirror Circuits on HSPICE 180nm Technology

Current mirrors are one of the most common buildings blocks both in analog and mixed-signal VLSI circuits. Current mirrors are very useful elements for performing current mode analog signal processing. It generated dc current in direct ratio with reference current.Thus used for biasing integratred circuits also as active load in amplifier design, scaling and replication purpose. This paper presents design and analysis of basic NMOS and PMOS current mirror with various conditions and also few concepts likecurrent steering and scaling, source degenerative circuit to improve output impedance.Synopsys HSPICE circuit simulator with Stanford NMOS and PMOS model at 180nm technology atVDD of 1.8V is used for simulation of all circuit. Simulation result shows NMOS current mirror power consumption of 3.9?W while PMOS current mirror takes 25?W power. Source degenerative circuit shows output impedance of 1203M?

VLSI Implementation of Modified Hamming Neural Network for non Binary Pattern Recognition

Artificial intelligence is integral part of a neural network is based on mathematical equations and artificial neurons. The focus here is the implementation of the Artificial Neural Network Architecture (ANN) with on chip learning in analog VLSI for pattern recognition. It is a maximum likelohood classifier which can be implemented using VLSI. Modified Hamming neural network architecture is presented.Thenew circuit is modified to accept real time inputs as well as to determine next close pattern with respect to input pattern.Modified digit recognition circuit was simulated using HSPICE level 49 model parameters with version 3.1180n at VDD of 3V. The circuit shows power consumption of 34mW and transient delay of 0.35nS

VLSI Realization of Switched Hamming Neural Network for 3-Bit Digit Recognition

This paper aims at analyzing neural network method in pattern recognition. HSPICE level 49 simulation of switched current mode hamming neural network is able to recognize any threebit digit provided its template is stored using current mirror. It determines highest input current signal and output it based on time division basisusing Winner Take All circuit (WTA) based on time division basis. The DC simulation shows power dissipation of 1.8517mW and rise time delay of 3.2318E-09

Patterns of epithelial cell abnormalities in Pap smears and its clinicopathological and demographic association: a descriptive study from Visakhapatnam city, Andhra Pradesh, India

Background: Cervical cancer is one of the leading cancers amongst women. Periodic pap screening is the simplest way to diagnose precancerous lesions. Factors such as ignorance, poverty poorly developed public healthcare delivery system put women in urban slums at a disadvantage for receiving any health screening activity. Objectives of the present study were to know the prevalence of epithelial cell abnormalities of the cervix among the subjects and to study the association with clinical and demographic characteristics.Methods: A camp based descriptive study was conducted in an urban ward. All women above the age of 20 years were included in the study. Data was recorded using a pretested questionnaire. Study variables included socio-demographic characteristics, symptoms of reproductive tract infection, findings of clinical examination, and Pap smear collection and evaluation. The latter was done from 194 women aged between 20-69 years. Pap smears were made by conventional Pap smear technique and reported according to The Revised Bethesda System of classification 2001(TBS).Results: Among the 194 women, in 8 subjects, the smears collected were unsatisfactory for evaluation. Analysis was done in the remaining 186 subjects. Among the latter, in 83.9%, the smears were negative for intraepithelial lesions (NIEL) and 16.1% revealed epithelial cell abnormalities (ECA). Among those with ECA, Atypical cells of undetermined significance (ASCUS) was identified in 66.67%, Low grade squamous intraepithelial lesions(LSIL) in 16.67%, Atypical squamous cells-cannot exclude HSIL (ASC-H) and Atypical glandular cells-not otherwise specified (AGC-NOS) in 6.67% each and High grade squamous intraepithelial lesions (HSIL) in 3.33%. Epithelial cell abnormalities were more common in women in the age group of 30-60 years (80%), they were more common in those with age at marriage between 13-18 years (63.3%) and in those with age at first child birth between 15-19 years (56.7%). Conclusions: Therefore there is a need for Pap screening at regular intervals through camp based approach in these populations to motivate the women, increase their awareness, ensure follow up and referral and timely intervention in appropriate cases.

MutLα heterodimers modify the molecular phenotype of Friedreich ataxia

This article has been made available through the Brunel Open Access Publishing Fund.Background: Friedreich ataxia (FRDA), the most common autosomal recessive ataxia disorder, is caused by a dynamic GAA repeat expansion mutation within intron 1 of FXN gene, resulting in down-regulation of frataxin expression. Studies of cell and mouse models have revealed a role for the mismatch repair (MMR) MutS-heterodimer complexes and the PMS2 component of the MutLα complex in the dynamics of intergenerational and somatic GAA repeat expansions: MSH2, MSH3 and MSH6 promote GAA repeat expansions, while PMS2 inhibits GAA repeat expansions. Methodology/Principal Findings: To determine the potential role of the other component of the MutLα complex, MLH1, in GAA repeat instability in FRDA, we have analyzed intergenerational and somatic GAA repeat expansions from FXN transgenic mice that have been crossed with Mlh1 deficient mice. We find that loss of Mlh1 activity reduces both intergenerational and somatic GAA repeat expansions. However, we also find that loss of either Mlh1 or Pms2 reduces FXN transcription, suggesting different mechanisms of action for Mlh1 and Pms2 on GAA repeat expansion dynamics and regulation of FXN transcription. Conclusions/Significance: Both MutLα components, PMS2 and MLH1, have now been shown to modify the molecular phenotype of FRDA. We propose that upregulation of MLH1 or PMS2 could be potential FRDA therapeutic approaches to increase FXN transcription. © 2014 Ezzatizadeh et al.This article has been made available through the Brunel Open Access Publishing Fund

Cluster Lenses

Clusters of galaxies are the most recently assembled, massive, bound structures in the Universe. As predicted by General Relativity, given their masses, clusters strongly deform space-time in their vicinity. Clusters act as some of the most powerful gravitational lenses in the Universe. Light rays traversing through clusters from distant sources are hence deflected, and the resulting images of these distant objects therefore appear distorted and magnified. Lensing by clusters occurs in two regimes, each with unique observational signatures. The strong lensing regime is characterized by effects readily seen by eye, namely, the production of giant arcs, multiple-images, and arclets. The weak lensing regime is characterized by small deformations in the shapes of background galaxies only detectable statistically. Cluster lenses have been exploited successfully to address several important current questions in cosmology: (i) the study of the lens(es) - understanding cluster mass distributions and issues pertaining to cluster formation and evolution, as well as constraining the nature of dark matter; (ii) the study of the lensed objects - probing the properties of the background lensed galaxy population - which is statistically at higher redshifts and of lower intrinsic luminosity thus enabling the probing of galaxy formation at the earliest times right up to the Dark Ages; and (iii) the study of the geometry of the Universe - as the strength of lensing depends on the ratios of angular diameter distances between the lens, source and observer, lens deflections are sensitive to the value of cosmological parameters and offer a powerful geometric tool to probe Dark Energy. In this review, we present the basics of cluster lensing and provide a current status report of the field.Comment: About 120 pages - Published in Open Access at: http://www.springerlink.com/content/j183018170485723/ . arXiv admin note: text overlap with arXiv:astro-ph/0504478 and arXiv:1003.3674 by other author

Tenascin-C Enhances Pancreatic Cancer Cell Growth and Motility and Affects Cell Adhesion through Activation of the Integrin Pathway

Background: Pancreatic cancer (PDAC) is characterized by an abundant fibrous tissue rich in Tenascin-C (TNC), a large ECM glycoprotein mainly synthesized by pancreatic stellate cells (PSCs). In human pancreatic tissues, TNC expression increases in the progression from low-grade precursor lesions to invasive cancer. Aim of this study was the functional characterization of the effects of TNC on biologic relevant properties of pancreatic cancer cells. Methods: Proliferation, migration and adhesion assays were performed on pancreatic cancer cell lines treated with TNC or grown on a TNC-rich matrix. Stable transfectants expressing the large TNC splice variant were generated to test the effects of endogenous TNC. TNC-dependent integrin signaling was investigated by immunoblotting, immunofluorescence and pharmacological inhibition. Results: Endogenous TNC promoted pancreatic cancer cell growth and migration. A TNC-rich matrix also enhanced migration as well as the adhesion to the uncoated growth surface of poorly differentiated cell lines. In contrast, adhesion to fibronectin was significantly decreased in the presence of TNC. The effects of TNC on cell adhesion were paralleled by changes in the activation state of paxillin and Akt. Conclusion: TNC affects proliferation, migration and adhesion of poorly differentiated pancreatic cancer cell lines and migh