Right-chiral sneutrinos and long-lived staus: event characteristics at the Large Hadron Collider

We investigate the signals of a supersymmetric scenario where the lighter tau-sneutrino is the lightest supersymmetric particle, while the lighter stau-state is the next lightest. We confirm that such a scenario can be motivated within the framework of minimal supergravity, with just the addition of a right-chiral neutrino superfield. Such a spectrum leads to rather unusual signals of supersymmetry, showing stable tracks of the stau in the muon chambers. We have studied two types of signals, namely, (a) two or more hard jets and two stau tracks, and (b) hard jets with two muons and two stau tracks. We demonstrate that the stau tracks can be distinguished from the muonic ones through proper kinematic cuts which also enable one to remove all standard model backgrounds.Comment: Latex2E, 18 pages, 8 eps figures included (To appear in Phys.Rev. D

Distinguishing split supersymmetry in Higgs signals at the Large Hadron Collider

We examine the possibility of detecting signals of split supersymmetry in the loop-induced decay h --> gamma gamma of the Higgs boson at the Large Hadron Collider, where charginos, as surviving light fermions of the supersymmetric spectrum, can contribute in the loop. We perform a detailed study of uncertainties in various parameters involved in the analysis, and thus the net uncertainty in the standard model prediction of the rate. After a thorough scan of the parameter space, taking all constraints into account, we conclude that it will be very difficult to infer about split supersymmetry from Higgs signals alone.Comment: 22 pages, 14eps figures, LateX, Changes in the figures and minor modifications in the text. Final version to appear in Physical Review

Analog and RF Performance Evaluation of Dual Metal Double Gate High-k Stack (DMDG-HKS) MOSFETs

Dual Metal Gate (DMG) technology was proposed to reduce the short channel effects (SCE’s) of double gate MOSFETs. But, DMG alone is not enough to rectify the problem of gate tunneling current due to thinning of oxide layer with device downscaling. So, the use of high-k dielectric as gate oxide is considered to overcome the gate tunneling effect. But, high gate dielectric thickness leads to higher fringing fields leading to undesirable higher gate capacitance. So, the use of oxide stack i.e. a combination of silicon dioxide and high-k dielectric material is preferred as gate oxide. This paper presents the evaluation of the analog performance of nMOS dual metal double gate with high-k oxide stack (DMDG-HKS) MOSFETs, comparing their performance with those exhibited by dual metal double gate (DMDG) transistors and single metal double gate (SMDG) transistors of identical dimensions. The analog performance has been investigated in subthreshold regime of operation by varying the channel length, gate oxide stack and considering different analog parameters extracted from the 2-D device simulations. It has been observed that the DMDG-HKS devices offer better transconductance gm, early voltage Va, intrinsic gain gm / gd, drain conductance gd, transconductance generation factor gm / Id, transition frequency fT, etc. The variation of these analog parameters has also been investigated by changing the equivalent oxide thickness (EOT) and channel length of the DMDG-HKS transistor and has been observed that above parameters tends to improve with channel length and EOT as well. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3194

Modulation of elasticity and interactions in charged lipid multibilayers: monovalent salt solutions

We have studied the electrostatic screening effect of NaCl solutions on the interactions between anionic lipid bilayers in the fluid lamellar phase using a Poisson-Boltzmann based mean-field approach with constant charge and constant potential limiting charge regulation boundary conditions. The full DLVO potential, including the electrostatic, hydration and van der Waals interactions, was coupled to thermal bending fluctuations of the membranes via a variational Gaussian Ansatz. This allowed us to analyze the coupling between the osmotic pressure and the fluctuation amplitudes and compare them both simultaneously with the measured dependence on the bilayer separation, determined by the small-angle X-ray scattering experiments. High-structural resolution analysis of the scattering data revealed no significant changes of membrane structure as a function of salt concentration. Parsimonious description of our results is consistent with the constant charge limit of the general charge regulation phenomenology, with fully dissociated lipid charge groups, together with a four-fold reduction of the membranes' bending rigidity upon increasing NaCl concentration.Comment: 18 pages, 5 figures, improved discussions of the steric parameter (or penetration coefficient) c, vestigial osmotic pressure and salt-induced reduction of bending rigidity of charged lipid bilayers, Langmuir (2016

Design parameter based method of partial discharge detection and location in power transformers

Insulation defect detection in time ensures higher operational reliability of power system assets. Power transformers are the most critical unit of power systems both from economical and operational front. Hence it becomes necessary to have knowledge of the actual insulation condition of transformer to increase dependability of the system. The performance and ageing of the transformer insulation is mainly affected by Partial discharges (PD). Proper diagnosis in terms of amplitude and location of partial discharge in a power transformer enables us to predict well in advance, with much confidence, the defect in insulation system, which avoids large catastrophic failures. In this work a 20kVA, 230/50kV single phase core type transformer is used for evaluation of the transfer function-based partial discharge detection and location using modeling of the winding, using design data. The simulation of capturing on-line PD pulses across the bushing tap capacitor is done for various tap positions. Standard PD source model is used to inject PD pulse signal at 10 tap locations in the winding and corresponding response signatures are captured at the bushing tap end (across 1000pF). The equivalent high frequency model of the winding is derived from the design parameters using analytical calculations and simulations in packages such as MAGNET and ANSOFT. The test conditions are simulated using ORCAD-9 and the results are evaluated for location accuracy using design parameter based PD monitoring method.

Functional Study of Oncogenic Transcription Factor ERG and its Signaling in Prostate Cancer

TMPRSS2–ERG is the most frequent type of genomic rearrangement present in prostate tumors, in which the 5- prime region of the TMPRSS2 gene is fused to the ERG oncogene. TMPRSS2, containing androgen response elements (AREs), is regulated by androgens in the prostate. The truncated TMPRSS2-ERG fusion transcript is overexpressed in half of the prostate cancer patients. The formation of TMPRSS2-ERG transcript is an early event in prostate carcinogenesis and previous in vivo and in vitro studies have shown ectopic ERG expression to be associated with increased cell invasion. However, the molecular function of ERG and its role in cell signaling is poorly understood. In this study, genomic rearrangement of ERG with TMPRSS2 was studied by using comparative genomic hybridization (CGH) in prostate cancer samples. The biological processes associated with the ERG oncogene expression in prostate epithelial cells were studied, and the results were compared with findings observed in clinical prostate tumor samples. The gene expression data indicated that increased WNT signaling and loss of cell adhesion were a characteristic of TMPRSS2- ERG fusion positive prostate tumor samples. Up- regulation of WNT pathway genes were present in ERG positive prostate tumors, with frizzled receptor 4 (FZD4) presenting with the highest association with ERG overexpression, as verified by quantitative reverse transcription-PCR, immunostaining, and immunoblotting in TMPRSS2-ERG positive VCaP prostate cancer cells. Furthermore, ERG and FZD4 silencing increased cell adhesion by inducing active β1-integrin and E-cadherin expression in VCaP cells. Furthermore, we found a novel inhibitor, 4-(chloromethyl) benzoyl chloride which inhibited the WNT signaling and induced similar phenotypic effects as observed after ERG or FZD4 down regulation in VCaP cells. In conclusion, this work deepens our understanding on the complex oncogenic mechanisms of ERG in prostate cancer that may help in developing drugs against TMPRSS2-ERG positive tumors.Siirretty Doriast

Distant Homes: Migrant Sensibilities and the Problems of Acculturation

Continued waves of diasporic movement over successive historical moments in South Asia make it difficult to homogenise all diaspora into one mould. The present paper explores the conflict between the process of acculturation and the longing for homeland experienced by three South Asian poets who belong to a specific period in modern diaspora. Contemporaries all, Agha Shahid Ali (1949-2001), Meena Alexander (1951-) and Imtiaz Dharker (1954-) express in their poetry their (c)overt sense of longing and attachment to the homeland even as they negotiate the different interstitial spaces they occupy. Their reinvention of their identity in the process of acculturation and their expanding political concerns lead them to look beyond the nation as home and develop a form of cosmopolitanism. Does this cosmopolitanism give them an assurance, a sense of belonging or an uneasy discomfort? I intend to discuss some of these issues as expressed in their poetry

Question of urban transport in India

Public bus transport is of great import in India. Not only is an efficient public bus system important for meeting the mobility needs in this rapidly growing economy, but a higher share of bus transport would also have a positive impact on pollution, both local and global, and energy demand. That apart, improved availability of public transport is critical for ensuring access to basic services such as education and health, and integrating rural communities into the economic mainstream. Hence, it is incumbent on governments in developing countries to institute appropriate policy initiatives to increase the share of public transport. The increasingly urban character of growth has led to a rapid growth in transportation activity in India cities