Rahul Mishra - Academia.edu (original) (raw)

Papers by Rahul Mishra

IEEE Consumer Electronics Magazine

Similar aggregation and β-sheet propensity of amino acids in globular proteins and amyloids, sugg... more Similar aggregation and β-sheet propensity of amino acids in globular proteins and amyloids, suggests comparable principles of their formation. Here we show that during the process of aggregation into amyloid-like fibers, these rules are not the same in an amino-acid-homopolymer (AAHP) polyglutamine (PolyGln). An aggregation kinetic analysis on nine-point mutants of a forty-six long PolyGln peptide was carried in physiological conditions. At the dynamic equilibrium state of aggregation, critical-concentration derived free-energy differences, signifying aggregation propensity of incorporated amino acids were obtained. None of the obtained propensities correlated with existing conventional aggregation and β-sheet propensities of the amino acids in proteins and amyloids. Further, the differential aggregation behavior of all the peptides only correlated with van der Waals volume of the incorporated amino acid and not with any other physicochemical characteristic of amino acids. The new ...

We consider the inference problem of reconstructing a visual stimulus from brain activity measure... more We consider the inference problem of reconstructing a visual stimulus from brain activity measurements (e.g. fMRI) that encode this stimulus. Recovering a complete image is complicated by the fact that neural representations are noisy, high-dimensional, and contain incomplete information about image details. Thus, reconstructions of complex images from brain activity require a strong prior. Here we propose to train generative adversarial networks (GANs) to learn a generative model of images that is conditioned on measurements of brain activity. We consider two challenges of this approach: First, given that GANs require far more data to train than is typically collected in an fMRI experiment, how do we obtain enough samples to train a GAN that is conditioned on brain activity? Secondly, how do we ensure that our generated samples are robust against noise present in fMRI data? Our strategy to surmount both of these problems centers around the creation of surrogate brain activity sampl...

BioMed Research International

Background. Femoral bone remodeling around hip prosthesis after total hip arthroplasty (THA) is d... more Background. Femoral bone remodeling around hip prosthesis after total hip arthroplasty (THA) is definite but unpredictable in time and place. This study aimed to investigate the implant-specific remodeling and periprosthetic bone mineral density (BMD) changes after implantation of the Ribbed anatomic cementless femoral stem. Methods. After power analysis, 41 patients who had undergone primary unilateral THA with the Ribbed anatomic cementless stem were included. BMD of the seven Gruen zones was measured by dual-energy X-ray absorptiometry, and the contact, fitness, and fixation of the femoral stem and proximal femur were analyzed by X-ray. Additional clinical outcome parameters were also recorded. Results. Compared with the contralateral unoperated side, significant reductions of BMD were detected in the distal zone (Gruen zone 4: 1.665±0.198 versus 1.568±0.242 g/cm2, P=0.001) and middle distal zone (Gruen zone 5: 1.660±0.209 versus 1.608±0.215 g/cm2, P=0.026) on the prosthetic side...

Nature Materials

Spintronics is a multidisciplinary field whose central theme is the active manipulation of spin d... more Spintronics is a multidisciplinary field whose central theme is the active manipulation of spin degrees of freedom in solid-state systems. Ferromagnetic spintronics has been a main focus as it offers non-volatile memory and logic applications through current-induced spintransfer torques 1-4. Enabling wider applications of such magnetic devices requires a lower switching current for a smaller cell while keeping the thermal stability of magnetic cells for non-volatility. As the cell size reduces, however, it becomes extremely difficult to meet this requirement with ferromagnets because spin-transfer torque for ferromagnets is a surface torque due to rapid spin dephasing 5,6 , leading to the 1/ferromagnet-thickness dependence of the spin-torque efficiency 7. Requirement of a larger switching current for a thicker and thus

Nature communications, Nov 8, 2017

Topological insulators with spin-momentum-locked topological surface states are expected to exhib... more Topological insulators with spin-momentum-locked topological surface states are expected to exhibit a giant spin-orbit torque in the topological insulator/ferromagnet systems. To date, the topological insulator spin-orbit torque-driven magnetization switching is solely reported in a Cr-doped topological insulator at 1.9 K. Here we directly show giant spin-orbit torque-driven magnetization switching in a Bi2Se3/NiFe heterostructure at room temperature captured using a magneto-optic Kerr effect microscope. We identify a large charge-to-spin conversion efficiency of ~1-1.75 in the thin Bi2Se3 films, where the topological surface states are dominant. In addition, we find the current density required for the magnetization switching is extremely low, ~6 × 10(5) A cm(-2), which is one to two orders of magnitude smaller than that with heavy metals. Our demonstration of room temperature magnetization switching of a conventional 3d ferromagnet using Bi2Se3 may lead to potential innovations in...

Journal of Inorganic and Organometallic Polymers and Materials

Magnetic SiC nanowires were obtained by the pyrolysis of iron containing polycarbosilane (PCS) wh... more Magnetic SiC nanowires were obtained by the pyrolysis of iron containing polycarbosilane (PCS) which in turn was synthesized by the reaction of polycarbosilane and iron (III) acetylacetonate [Fe(acac) 3 ] in solvent. Characterization of synthesized polycarbosilane and Fe-SiC were performed with Fourier transformation infrared spectroscopy, energy dispersive X-ray spectrometry, powder X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, electron spin resonance and vibrating sample magnetometer.

Physical Review Applied

We theoretically study the influence of a predominant field-like spin-orbit torque on the magneti... more We theoretically study the influence of a predominant field-like spin-orbit torque on the magnetization switching of small devices with a uniform magnetization. We show that for a certain range of ratios (0.23-0.55) of the Slonczewski to the field-like torques, it is possible to deterministically switch the magnetization without requiring any external assist field. A precise control of the pulse length is not necessary, but the pulse edge sharpness is critical. The proposed switching scheme is numerically verified to be effective in devices by micromagnetic simulations. Switching without any external assist field is of great interest for the application of spin-orbit torques to magnetic memories.

2016 International Conference on Next Generation Intelligent Systems (ICNGIS), 2016

Heteroatom Chem, 2009

... On the Reactivity of Metal and Organometallic Halides toward R3 Sn O SnR3 Systems Kiran Singh... more ... On the Reactivity of Metal and Organometallic Halides toward R3 Sn O SnR3 Systems Kiran Singhal, Rahul Mishra, and Prem Raj Department of Chemistry, University of Lucknow, Lucknow 226 007, India Received 12 April 2009; revised 20 June 2009 ...

PloS one, 2015

VopK, a type III effector protein, has been implicated in the pathogenesis of Vibrio cholerae str... more VopK, a type III effector protein, has been implicated in the pathogenesis of Vibrio cholerae strains belonging to diverse serogroups. Ectopic expression of this protein exhibits strong toxicity in yeast model system. In order to map critical residues in VopK, we scanned the primary sequence guided by available data on various toxins and effector proteins. Our in silico analysis of VopK indicated the presence of predicted MCF1-SHE (SHxxxE) serine peptidase domain at the C-terminus region of the protein. Substitution of each of the predicted catalytic triad residues namely Ser314, His353 and Glu357 with alanine resulted in recombinant VopK proteins varying in lethality as evaluated in yeast model system. We observed that replacement of glutamate357 to alanine causes complete loss in toxicity while substitutions of serine314 and histidine353 with alanine exhibited partial loss in toxicity without affecting the stability of variants. In addition, replacement of another conserved serine...

ACS Applied Materials & Interfaces, 2015

Restoring the antibacterial properties of existing antibiotics is of great concern. Herein, we pr... more Restoring the antibacterial properties of existing antibiotics is of great concern. Herein, we present, for the first time, the formation and deposition of stable antibiotic nanoparticles (NPs) on graphene oxide (GO) sheets by a facile one-step sonochemical technique. Sonochemically synthesized graphene oxide/tetracycline (GO/TET) composite shows enhanced activity against both sensitive and resistant Staphylococcus aureus (S. aureus). The size and deposition of tetracycline (TET) nanoparticles on GO can be controlled by varying the sonication time. The synthesized NPs ranged from 21 to 180 nm. Moreover, ultrasonic irradiation does not cause any structural and chemical changes to the TET molecule as confirmed by Fourier transform infrared spectroscopy (FTIR). The virtue of π-π stacking between GO and TET additionally facilitate the coating of TET NPs upon GO. A time dependent release kinetics of TET NPs from the GO surface is also monitored providing important insights regarding the mechanism of antibacterial activity of GO/TET composites. Our results show that the GO/TET composite is bactericidal in nature, resulting in similar values of minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). This composite is found to be active against TET resistant S. aureus at a concentration four times lower than the pristine TET. The sensitive S. aureus follows the same trend showing six times lower MIC values compared to pristine TET. GO shows no activity against both sensitive and resistant S. aureus even at a concentration as high as 1 mg/mL but influences the biocidal activity of the GO/TET composite. We propose that the unique structure and composition manifested by GO/TET composites may be further utilized for different formulations of antibiotics with GO. The sonochemical method used in this work can be precisely tailored for the stable deposition of a variety of antibiotics on the GO surface to reduce health risks and increase the spectrum of applications.

International Journal of Advanced Research in Artificial Intelligence, 2013

The purpose of this paper is to explore a new way of autonomous mapping. Current systems using pe... more The purpose of this paper is to explore a new way of autonomous mapping. Current systems using perception techniques like LAZER or SONAR use probabilistic methods and have a drawback of allowing considerable uncertainty in the mapping process. Our approach is to break down the environment, specifically indoor, into reachable areas and objects, separated by boundaries, and identifying their shape, to render various navigable paths around them. This is a novel method to do away with uncertainties, as far as possible, at the cost of temporal efficiency. Also this system demands only minimum and cheap hardware, as it relies on only Infra-Red sensors to do the job.

2007 IEEE International SOI Conference, 2007

ABSTRACT

Moderate and Deep Sedation in Clinical Practice, 2012

International Journal of Research in Engineering and Technology, 2014

This paper investigates the effect of fly ash (generated from thermal power plant, Panki, Kanpur)... more This paper investigates the effect of fly ash (generated from thermal power plant, Panki, Kanpur) on geotechnical properties of local soil, Bhauti Kanpur (U.P), INDIA. The fly ash used in the experimental work was of Class 'F' and soil was clayey in nature .Fly ash collected from the hopper attached to an electrostatic precipitator when coal was changed at a coal fired power plant. Concerning the major challenges regarding the safe reuse, management and disposal of these wastes an attempt has been made to mix fly ash at 5,10, 15, 20, 25, and 30% on the basis of dry weight with local clay soil. To understand the behavior of fly ash with soil, numbers of laboratory experiments were performed on the local soil (clay) and contaminated soil with varying percentage of fly ash. As the result, it is shown that all the investigated properties were decreased except CBR value and optimum moisture content.