3-D GPU Based Real Time Diffuse Optical Tomographic System

3-Dimensional Diffuse Optical Tomographic (3-D DOT) image reconstruction algorithm is computationally complex and requires excessive matrix computations and thus hampers reconstruction in real time. In this paper, we present near real time 3D DOT image reconstruction that is based on Broyden approach for updating Jacobian matrix. The Broyden method simplifies the algorithm by avoiding re-computation of the Jacobian matrix in each iteration. We have developed CPU and heterogeneous CPU/GPU code for 3D DOT image reconstruction in C and MatLab programming platform. We have used Compute Unified Device Architecture (CUDA) programming framework and CUDA linear algebra library (CULA) to utilize the massively parallel computational power of GPUs (NVIDIA Tesla K20c). The computation time achieved for C program based implementation for a CPU/GPU system for 3 planes measurement and FEM mesh size of 19172 tetrahedral elements is 806 milliseconds for an iteration.

Combined inhalation and oral supplementation of Vitamin A and Vitamin D: A possible prevention and therapy for tuberculosis

Tuberculosis is continuing as a problem of mankind. With evolution, MDR and XDR forms of tuberculosis have emerged from drug sensitive strain. MDR and XDR strains are resistant to most of the antibiotics, making the management more difficult. BCG vaccine is not providing complete protection against tuberculosis. Therefore new infections are spreading at a tremendous rate. At the present moment there is experimental evidence to believe that Vitamin A and Vitamin D has anti-mycobacterial property. It is in this context, we have hypothesized a host based approach using the above vitamins that can cause possible prevention and cure of tuberculosis with minimal chance of resistance or toxicity. (C) 2015 Elsevier Ltd. All rights reserved.

On linear series and a conjecture of D. C. Butler

Let C be a smooth irreducible projective curve of genus g and L a line bundle of degree d generated by a linear subspace V of H-0 (L) of dimension n+1. We prove a conjecture of D. C. Butler on the semistability of the kernel of the evaluation map V circle times O-C -> L and obtain new results on the stability of this kernel. The natural context for this problem is the theory of coherent systems on curves and our techniques involve wall crossing formulae in this theory.

Adaptive Mesh Refinement for Fast Convergence of EFIE-Based 3-D Extraction

3-D full-wave method of moments (MoM) based electromagnetic analysis is a popular means toward accurate solution of Maxwell's equations. The time and memory bottlenecks associated with such a solution have been addressed over the last two decades by linear complexity fast solver algorithms. However, the accurate solution of 3-D full-wave MoM on an arbitrary mesh of a package-board structure does not guarantee accuracy, since the discretization may not be fine enough to capture spatial changes in the solution variable. At the same time, uniform over-meshing on the entire structure generates a large number of solution variables and therefore requires an unnecessarily large matrix solution. In this paper, different refinement criteria are studied in an adaptive mesh refinement platform. Consequently, the most suitable conductor mesh refinement criterion for MoM-based electromagnetic package-board extraction is identified and the advantages of this adaptive strategy are demonstrated from both accuracy and speed perspectives. The results are also compared with those of the recently reported integral equation-based h-refinement strategy. Finally, a new methodology to expedite each adaptive refinement pass is proposed.

Eu3+-activated SrMoO4 phosphors for white LEDs applications: Synthesis and structural characterization

We report the synthesis of Eu3+-activated SrMoO4 phosphors by the facile nitrate-citrate gel combustion method. Powder XRD and Rietveld refinement data confirmed that these phosphors have a monophasic scheelite-type tetragonal structure with space group I4(1)/a (No. 88). FESEM micrographs indicate the agglomerated spherical particles. FTIR spectra showed four stretching and bending vibrational modes (2A(u) and 2E(u)). UV-Visible absorption spectroscopy illustrated that the optical band gap energy (E-g) values increase with increase in Eu3+ concentration. The host SrMoO4 phosphor exhibited an intense blue emission under UV excitation (368 nm). The Eu3+-activated SrMoO4 phosphors revealed characteristic luminescence due to Eu3+ ion corresponding to D-5(1) -> F-7(J) (J = 1,2) and D-5(0) -> F-7(J) (J = 1,2,3,4) transitions upon 465 nm excitation. The electric dipole transition located at 615 nm (D-5(0) -> F-7(2)) was stronger than the magnetic dipole transition located at 592 nm (D-5(0) -> F-7(1)). Intensity parameters (Omega(2), Omega(4)) and radiative properties such as transition probabilities (A(T)), radiative lifetime (tau(rad)) and branching ratio (beta) of Eu3+-activated SrMoO4 phosphors were calculated using the Judd-Ofelt theory. Based on the CIE chromaticity diagram, these phosphors can be promising materials for the development of blue and orange-red component in white LEDs. (C) 2015 Elsevier B.V. All rights reserved.

Solid state structure of p-bromo phenyl 4,5,7-tri-O-benzyl-beta-D-glycero-D-talo-septanoside and an analysis of non-covalent interactions

The solid state structure of a new seven-membered sugar oxepane derivative, namely, p-bromo phenyl 4,5,7-tri-O-benzyl-beta-D-glycero-D-talo-septanoside is discussed, as determined through single crystal X-ray structural determination and in relation to their conformational features. The molecule adopts twist-chair as the preferred conformation, with conformational descriptor (TC2,3)-T-0,1. The solid state packing of molecules is governed by a rich network of non-covalent bonding originating from O-H center dot center dot center dot O, C-H center dot center dot center dot pi, C-H center dot center dot center dot Br and aromatic pi center dot center dot center dot pi interactions that stabilize the packing of molecules in the crystal. (C) 2015 Elsevier Ltd. All rights reserved.

Timing Recovery Algorithms and Architectures for 2-D Magnetic Recording Systems

We investigate the problem of timing recovery for 2-D magnetic recording (TDMR) channels. We develop a timing error model for TDMR channel considering the phase and frequency offsets with noise. We propose a 2-D data-aided phase-locked loop (PLL) architecture for tracking variations in the position and movement of the read head in the down-track and cross-track directions and analyze the convergence of the algorithm under non-separable timing errors. We further develop a 2-D interpolation-based timing recovery scheme that works in conjunction with the 2-D PLL. We quantify the efficiency of our proposed algorithms by simulations over a 2-D magnetic recording channel with timing errors.

High T-g fluoranthene-based electron transport materials for organic light-emitting diodes

In this study, fluoranthene-based derivatives with a high thermal stability were synthesized for applications in organic electroluminescent devices. The two derivatives synthesized in this study, bis(4-(7,9,10-triphenylfluoranthen-8-yl)phenyl)sulfane (TPFDPS) and 2,8-bis(7,9,10-triphenylfluoranthen-8-yl)dibenzob,d]thiophene (TPFDBT), were characterized by cyclic voltammetry, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). TPFDPS exhibits a high T-g of 210 degrees C while TPFDBT is crystalline in nature. Both the derivatives are thermally stable up to 500 degrees C. The charge transport studies reveal predominant electron transport properties. Subsequently, we fabricated blue OLEDs with 2-tert-butyl-9,10-bis-(beta-naphthyl)-anthracene (TBADN) as the emitting layer to demonstrate the applications of these molecules as an electron transporting layer.

Contrasting Electronic Requirements for C-H Binding and C-H Activation in d(6) Half-Sandwich Complexes of Rhenium and Tungsten

A computational study of the interaction half-sandwich metal fragments (metal=Re/W, electron count=d(6)), containing linear nitrosyl (NO+), carbon monoxide (CO), trifluorophosphine (PF3), N-heterocyclic carbene (NHC) ligands with alkanes are conducted using density functional theory employing the hybrid meta-GGA functional (M06). Electron deficiency on the metal increases with the ligand in the order NHC < CO < PF3 < NO+. Electron-withdrawing ligands like NO+ lead to more stable alkane complexes than NHC, a strong electron donor. Energy decomposition analysis shows that stabilization is due to orbital interaction involving charge transfer from the alkane to the metal. Reactivity and dynamics of the alkane fragment are facilitated by electron donors on the metal. These results match most of the experimental results known for CO and PF3 complexes. The study suggests activation of alkane in metal complexes to be facile with strong donor ligands like NHC. (C) 2015 Wiley Periodicals, Inc.

An Unbiased Risk Estimator for Multiplicative Noise - Application to 1-D Signal Denoising

The effect of multiplicative noise on a signal when compared with that of additive noise is very large. In this paper, we address the problem of suppressing multiplicative noise in one-dimensional signals. To deal with signals that are corrupted with multiplicative noise, we propose a denoising algorithm based on minimization of an unbiased estimator (MURE) of meansquare error (MSE). We derive an expression for an unbiased estimate of the MSE. The proposed denoising is carried out in wavelet domain (soft thresholding) by considering time-domain MURE. The parameters of thresholding function are obtained by minimizing the unbiased estimator MURE. We show that the parameters for optimal MURE are very close to the optimal parameters considering the oracle MSE. Experiments show that the SNR improvement for the proposed denoising algorithm is competitive with a state-of-the-art method.

Synthesizing Racy Tests

Subtle concurrency errors in multithreaded libraries that arise because of incorrect or inadequate synchronization are often difficult to pinpoint precisely using only static techniques. On the other hand, the effectiveness of dynamic race detectors is critically dependent on multithreaded test suites whose execution can be used to identify and trigger races. Usually, such multithreaded tests need to invoke a specific combination of methods with objects involved in the invocations being shared appropriately to expose a race. Without a priori knowledge of the race, construction of such tests can be challenging. In this paper, we present a lightweight and scalable technique for synthesizing precisely these kinds of tests. Given a multithreaded library and a sequential test suite, we describe a fully automated analysis that examines sequential execution traces, and produces as its output a concurrent client program that drives shared objects via library method calls to states conducive for triggering a race. Experimental results on a variety of well-tested Java libraries yield 101 synthesized multithreaded tests in less than four minutes. Analyzing the execution of these tests using an off-the-shelf race detector reveals 187 harmful races, including several previously unreported ones.

Spectral characterizations and photophysical properties of one-step synthesized blue fluorescent 4 `-aryl substituted 2,2 `:6 `,2 `'-terpyridine for OLEDs application

We have synthesized a series of 4'-aryl substituted 2,2':6',2 `'-terpyridine (terpy) derivatives, namely 4'-(4-methylphenyl)-2,2':6',2 `'-terpyridine (C-1), 4'-(2-furyl)-2,2':6'2 `'-terpyridine (C-2), and 4'-(3,4,5-trimethoxyphenyl)-2,2':6',2 `'-terpyridine (C-3). The synthesized terpy compounds were characterized by elemental analyses, FTIR, NMR (H-1 and C-13), and ESI-Mass spectrometry. Photophysical, electrochemical and thermal properties of terpy compounds were systematically studied. Maximum excitation band was observed between 240 and 330 nm using UV-visible spectra, and maximum emission peaks from PL spectra were observed at 385, 405 and 440 nm for C-1, C-2 and C-3 respectively. Fluorescence lifetime (tau) of the fluorophores was found to be 035 and 1.55 ns at the excitation wavelength of 406 nm for C-1 and C-2 respectively, and tau value for C-3 was found to be 0.29 ns at the excitation wavelength of 468 nm. We noticed that the calculated values of HOMO energy levels were increased from 5.96 (C-1) to 6.08 (C-3) eV, which confirms that C-3 derivative is more electrons donating in nature. The calculated electrochemical band gaps were 2.95, 2.82 and 3.02 eV for C-1, C-2 and C-3 respectively. These blue fluorescent emitter derivatives can be used as an electron transport and electroluminescent material to design the blue fluorescent organic light emitting diode (OLED) applications. (C) 2015 Elsevier B.V: All rights reserved.

Development and Evaluation of Prussian Blue Mediated Glucose Sensor for Reverse Iontophoresis Application

The screen printed electrochemical glucose sensor is developed suitable for revere iontophoresis (RI) application. Glucose oxidase is immobilized on screen printed sensor using crosslinking method. Electrochemical and material characterization studies are conducted on the developed sensor and the obtained results confirm the suitability of the developed sensor for RI application. The developed sensor is validated by conducting clinical investigations on 10 human subjects through RI. A correlation is established between the blood glucose and extracted glucose, and correlation is found to be 0.73. (C) 2015 The Electrochemical Society. All rights reserved.

Cadmium Sulfide Nanocrystal Sensitized Vertically Aligned Titanium Dioxide Rods for Large Area Image Sensors on 3-D Substrates

We discuss here a semiconductors assembly comprising of titanium dioxide (TiO2) rods sensitized by cadmium sulfide (CdS) nanocrystals for potential applications in large area electronics on three dimensional (3-D) substrates. Vertically aligned TiO2 rods are grown on a substrate using a 150 degrees C process flow and then sensitized with CdS by SILAR method at room temperature. This structure forms an effective photoconductor as the photo-generated electrons are rapidly removed from the CdS via the TiO2 thereby permitting a hole rich CdS. Current-voltage characteristics are measured and models illustrate space charge limited photo-current as the mechanism of charge transport at moderate voltage bias. The stable assembly and high speed are achieved. The frequency response with a loading of 10 pF and 9 M Omega shows a half power frequency of 100 Hz. (C) 2015 The Electrochemical Society. All rights reserved.

Study of H/D exchange rates to derive the strength of intramolecular hydrogen bonds in halo substituted organic building blocks: An NMR spectroscopic investigation

Rates of hydrogen/deuterium (H/D) exchange determined by H-1 NMR spectroscopy are utilized to derive the strength of hydrogen bonds and to monitor the electronic effects in the site-specific halogen substituted benzamides and anilines. The theoretical fitting of the time dependent variation of the integral areas of H-1 NMR resonances to the first order decay function permitted the determination of HID exchange rate constants (k) and their precise half-lives (t(1/2)) with high degree of reproducibility. The comparative study also permitted the unambiguous determination of relative strength of hydrogen bonds and the contribution from electronic effects on the HID exchange rate. (C) 2015 Elsevier B.V. All rights reserved.