50175 research outputs found
Sort by
Auto-Reactive Th17-Cells Trigger Obsessive-Compulsive-Disorder Like Behavior in Mice With Experimental Autoimmune Encephalomyelitis
No full textTh17-lymphocytes are well known for their deleterious role in autoimmunity. But does the notoriety of this repertoire extend beyond autoimmunity? In the present study we employed experimental autoimmune encephalomyelitis as model system to study the role auto-reactive Th17 cells in neuropsychiatric disorders. The mice with experimental autoimmune encephalomyelitis exhibited exaggerated grooming activity. The observed behavioral anomaly resembled obsessive compulsive disorder (OCD) upon analysis of grooming microstructure, induced grooming, marble burying and nestlet shredding. The observed OCD like behavior was relieved upon Th17 cell depletion; alternatively, it could alone be induced by adoptive transfer of myelin oligodendrocyte glycoprotein (35-55) reactive Th17 in B6.Rag1(-/-) mice. The observed OCD like behavior was also alleviated upon treatment with a selective serotonin reuptake inhibitor, fluoxetine
Resonant Transport in Single Diketopyrrolopyrrole Junctions
No full textWe study the single-molecule transport properties of small bandgap diketopyrrolopyrrole oligomers (DPPn, n = 1-4) with lengths varying from 1 to 5 nm. At a low bias voltage, the conductance decays exponentially as a function of length indicative of nonresonant transport. However, at a high bias voltage, we observe a remarkably high conductance close to 10(-2) Go with currents reaching over 0.1 mu A across all four oligomers. These unique transport properties, together with density functional theory-based transport calculations, suggest a mechanism of resonant transport across the highly delocalized DPP backbones in the high bias regime. This study thus demonstrates the unique properties of diketopyrrolopyrrole derivatives in achieving highly efficient long-range charge transport in single molecule devices
Evaporative Crystallization in Drops on Superhydrophobic and Liquid-Impregnated Surfaces
No full textMineral-fouling induced corrosion and deterioration of marine vessels, aircraft, and coastal structures is due in part from structural intrusion of crystals grown from ocean-generated saline drops. As such, much work has explored surface treatments that induce hydrophobicity or introduce barriers for antifouling and corrosion prevention; however, the efficacy of these strategies will be altered by the underlying substrate texture. Here, we study the behavior of evaporating saline drops on superhydrophobic and liquid-impregnated surfaces as a function of surface texture. On superhydrophobic surfaces, four disparate regimes (which are not observed for particle-laden drops) emerge as a function of the substrate solid fraction: Cassie-pinning, Cassie-gliding, Cassie-Wenzel transition, and Wenzel. These regimes control the morphology of the resultant crystal deposits. In contrast to the superhydrophobic surfaces, spreading liquid-impregnated surfaces demonstrate minimal influence of solid fraction on evaporative crystallization. The area, area localization, timescale of evaporation, and deposit morphology are all normalized by the presence of the lubricating layer, thus introducing an efficient method of eliminating crystal ``coffee rings'' as well as reducing the potential for fouling and corrosion
An Integrated Magnetic Actuation System for High-Speed Atomic Force Microscopy
No full textHigh-speed atomic force microscopy enables in situ studies of dynamic phenomena at the nanometer-scale. This paper presents the design, fabrication, and evaluation of an integrated magnetic actuation system for high-speed atomic force microscopy. The proposed system consists of a microcantilever probe with an attached permanent magnet particle and a microactuator for generation of magnetic field. Novel geometries are proposed for the probe, the magnetic particle, and the actuator that together result in a high bandwidth and adequate actuation gain. A lumped parameter model is developed for the probe's dynamics and employed to optimize its design. Subsequently the integrated actuation system has been fabricated and evaluated. The actuator has been shown to generate actuation fields as high as 216 G with associated temperature rise of less than 8 degrees C. The probe has been evaluated to have an Eigen-frequency of 104 kHz with an actuation gain of 1 nm/G in air. Characterization of the probe in water reveals the reduction in Eigen-frequency to be merely 23%, which is nearly 3-fold less than that of a conventional probe. Finally, the developed actuation system has been employed to perform high-speed dynamic mode imaging of a grating inside aqueous medium at various imaging rates up to 1.25 frames/s
A COMPLETE CHARACTERIZATION OF BIRKHOFF-JAMES ORTHOGONALITY IN INFINITE DIMENSIONAL NORMED SPACE
No full textIn this paper, we study Birkhoff-James orthogonality of bounded linear operators and give a complete characterization of Birkhoff-James orthogonality of bounded linear operators on infinite dimensional real normed linear spaces. As an application of the results obtained, we prove a simple but useful characterization of Birkhoff-James orthogonality of bounded linear functionals defined on a real normed linear space, provided the dual space is strictly convex. We also provide separate necessary and sufficient conditions for smoothness of bounded linear operators on infinite dimensional normed linear spaces
DFG partitioning algorithms for coarse grained reconfigurable array assisted RTL simulation accelerators
No full textAs the complexity of circuit design increases, verification of these circuits through simulation also becomes extremely challenging. This creates a bottleneck in the IC design process. Distributed simulation is one way of solving this problem where the simulation workload is distributed among the parallel processors involved in the simulation. However the design has to be carefully partitioned for this purpose. In order to perform distributed simulation, many efficient partitioning algorithms have been proposed till date. These algorithms mostly partition gate level netlist or logic circuits and reduces inter-processor communication by minimizing cutsize for a given constraint of load balance. In this paper, we present two different partitioning schemes for performing distributed simulation. They are: a Discrete Particle Swarm Optimization (DPSO) based partitioning algorithm (DPSO-PA) and an effective partitioning heuristic. These algorithms partitions Data Flow Graph (DFG) for a recently proposed Coarse Grained Reconfigurable Array assisted Hardware Accelerator (CGRA-HA). We also propose an improved version of the original DPSO methodology through careful selection of initial partition sets. It is found that the proposed heuristic based partitioning algorithm outperforms the modified DPSO-PA in terms of lesser cut-edges
Cation distributions and magnetism of Al-substituted CoFe2O4 - NiFe2O4 solid solutions synthesized by sol-gel auto-combustion method
No full textAluminium substituted cobalt-nickel ferrite nanoparticles were synthesized by citrate gel auto-combustion method followed by annealing at 1000 degrees C for 1 h in air. Scanning electron micrographs of all the samples show crystalline particles of irregular morphology with a small variation in particle sizes (similar to 110-160 nm). From the analysis of the X-ray diffraction results we observed that the unit cell parameter decreases linearly with increase in aluminium concentration due to the smaller ionic radius of the Al3+ ions substituting the other cations such as Co2+, Ni2+ and Fe3+ ions in the compounds. The room temperature Mossbauer spectra of the samples show Zeeman split sextet patterns corresponding to the tetrahedral (Th) and octahedral (Oh) interstitial iron (Fe3+) cations. The observed magnetic hyperfine field (B-hf) decreases with increase in Al-concentration due to the distribution of diamagnetic Al3+ in the environment of Fe-57 probe atoms. The saturation magnetization measured by Vibrating Sample Magnetometer (VSM) shows a similar trend like that of Bhf. The distributions of the cations obtained from the Rietveld refinement and Mossbauer spectroscopy results indicate an increase in Fe3+(Th)/Fe3+ (Oh) occupancy-ratio on increasing Al3+ concentration, and Ni-2 cations prefer the octahedral site, whereas Co-2 and Al3+ ions redistribute themselves in tetrahedral and octahedral sites, in the ratio 2:3
Comparative functional analysis of proteins containing low-complexity predicted amyloid regions
No full textBackground: In both prokaryotic and eukaryotic proteins, repeated occurrence of a single or a group of few amino acids are found. These regions are termed as low complexity regions (LCRs). It has been observed that amino acid bias in LCR is directly linked to their uncontrolled expansion and amyloid formation. But a comparative analysis of the behavior of LCR based on their constituent amino acids and their association with amyloidogenic propensity is not available. Methods: Firstly we grouped all LCRs on the basis of their composition: homo-polymers, positively charged amino acids, negatively charged amino acids, polar amino acids and hydrophobic amino acids. We analyzed the compositional pattern of LCRs in each group and their propensity to form amyloids. The functional characteristics of proteins containing different groups of LCRs were explored using DAVID. In addition, we also analyzed the classes, pathways and functions of human proteins that form amyloids in LCRs. Results: Among homopolymeric LCRs, the most common was Gln repeats. LCRs composed of repeats of Met and aromatic amino acids were amongst the least occurring. The results revealed that LCRs composed of negatively charged and polar amino acids were more common in comparison to LCRs formed by positively charged and hydrophobic amino acids. We also noted that generally proteins with LCRs were involved in transcription but those with Gly repeats were associated to translational activities. Our analysis suggests that proteins in which LCR is composed of hydrophobic residues are more prone toward amyloid formation. We also found that the human proteins with amyloid forming LCRs were generally involved in binding and catalytic activity. Discussion: The presented analysis summarizes the most common and least occurring LCRs in proteins. Our results show that though repeats of Gln are the most abundant but Asn repeats make longest stretch of low complexity. The results showed that potential of LCRs to form amyloids varies with their amino acid composition
Multicast Networks Solvable over Every Finite Field
No full textIn this work, it is revealed that an acyclic multicast network that is scalar linearly solvable over Galois Field of two elements, GF(2), is solvable over all higher finite fields. An algorithm which, given a GF(2) solution for an acyclic multicast network, computes the solution over any arbitrary finite field is presented. The concept of multicast matroid is introduced in this paper. Gammoids and their base-orderability along with the regularity of a binary multicast matroid are used
Codes with Combined Locality and Regeneration Having Optimal Rate, d(min) and Linear Field Size
No full textIn this paper, we study vector codes with all-symbol locality, where the local code is either a Minimum Bandwidth Regenerating (MBR) code or a Minimum Storage Regenerating (MSR) code. In the first part, we present vector codes with all-symbol MBR locality, for all parameters, that have both optimal minimum-distance and optimal rate. These codes combine ideas from two popular codes in the distributed storage literature; Product-Matrix codes and Tamo-Barg codes. In the second part which deals with codes having all-symbol MSR locality, we follow a Pairwise Coupling Transform-based approach to arrive at optimal minimum-distance and optimal rate, for a range of parameters. All the code constructions presented in this paper have a low field-size that grows linearly with the code-length n