Extended screened exchange functional derived from transcorrelated density functional theory.

PubMed

Umezawa, Naoto

2017-09-14

We propose a new formulation of the correlation energy functional derived from the transcorrelated method in use in density functional theory (TC-DFT). An effective Hamiltonian, H TC , is introduced by a similarity transformation of a many-body Hamiltonian, H, with respect to a complex function F: H TC =1FHF. It is proved that an expectation value of H TC for a normalized single Slater determinant, D n , corresponds to the total energy: E[n] = ⟨Ψ n |H|Ψ n ⟩/⟨Ψ n |Ψ n ⟩ = ⟨D n |H TC |D n ⟩ under the two assumptions: (1) The electron density nr associated with a trial wave function Ψ n = D n F is v-representable and (2) Ψ n and D n give rise to the same electron density nr. This formulation, therefore, provides an alternative expression of the total energy that is useful for the development of novel correlation energy functionals. By substituting a specific function for F, we successfully derived a model correlation energy functional, which resembles the functional form of the screened exchange method. The proposed functional, named the extended screened exchange (ESX) functional, is described within two-body integrals and is parametrized for a numerically exact correlation energy of the homogeneous electron gas. The ESX functional does not contain any ingredients of (semi-)local functionals and thus is totally free from self-interactions. The computational cost for solving the self-consistent-field equation is comparable to that of the Hartree-Fock method. We apply the ESX functional to electronic structure calculations for a solid silicon, H - ion, and small atoms. The results demonstrate that the TC-DFT formulation is promising for the systematic improvement of the correlation energy functional.

Appraisal of the nitrogen-15 natural-abundance method for quantifying dinitrogen fixation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bremer, E.; van Kessel, C.

Several investigators have questioned the use of the {sup 15}N natural-abundance method of estimating N{sub 2} fixation because of variability in soil {delta}{sup 15}N and small differences between the {delta}{sup 15}N of soil N and atmospheric N. Investigations were conducted to compare the {sup 15}N natural-abundance and {sup 15}N-isotope-dilution methods for estimating N{sub 2} fixation of field-grown pea (Pisum sativum L.) and lentil (Lens culinaris Medik.). Spatial variability was assessed at three sites by determining the {delta}{sup 15}N of non-N{sub 2}-fixing plants. Seasonal variation in {delta}{sup 15}N for spring and winter wheat (Triticum aestivum L.), flax (Linum usitatissimum L.), barleymore » (Hordeum vulgare L.), rape (Brassica napus L.) and lentil was determined at one site. Comparisons between {delta}{sup 15}N and {sup 15}N-enriched isotope-dilution methods for estimating N{sub 2} fixation by lentil were conducted at several sites over a 3-yr period. Variability in {delta}{sup 15}N of the reference plant was site dependent: the {delta}{sup 15}N ranged from 2.8 to 9.3 at the first site, 3.4 to 8.8 at the second site, and 3.5 to 6.2 at the third site. The average {delta}{sup 15}N of four of the five non-N{sub 2}-fixing plants increased from 5.4 at 42 d after planting to 6.9 at the final harvest. The fifth non-N{sub 2}-fixing plant, rape, accumulated most of its N during the first 42 d after planting, and its {delta}{sup 15}N value declined from 8.1 at 42 d after planting to 7.3 at the final harvest. Estimates of N{sub 2} fixation were not significantly different in 18 out of 21 comparisons; in two comparisons in the {delta}{sup 15}N method and in one comparison the {sup 15}N-enriched method provided higher estimates of N{sub 2} fixation. Overall, both methods appeared to provide equally reliable estimates of N{sub 2} fixation for lentil.« less

New reference materials for nitrogen-isotope-ratio measurements

USGS Publications Warehouse

Böhlke, John Karl; Gwinn, C. J.; Coplen, T. B.

1993-01-01

Three new reference materials were manufactured for calibration of relative stable nitrogen-isotope-ratio measurements: USGS25 (ammonium sulfate) d15N' = -30 per mil; USGS26 (ammonium sulfate) d15N' = +54 per mil; USGS32 (potassium nitrate) d15N' = +180 per mil, where d15N', relative to atmospheric nitrogen, is an approximate value subject to change following interlaboratory comparisons. These materials are isotopically homogeneous in aliquots at least as small as 10 µmol N2 (or about 1-2 mg of salt). The new reference materials greatly extend the range of d15N values of internationally distributed standards, and they allow normalization of d15N measurements over almost the full range of known natural isotope variation on Earth. The methods used to produce these materials may be adapted to produce homogeneous local laboratory standards for routine use.

Dynamical density delay maps: simple, new method for visualising the behaviour of complex systems

PubMed Central

2014-01-01

Background Physiologic signals, such as cardiac interbeat intervals, exhibit complex fluctuations. However, capturing important dynamical properties, including nonstationarities may not be feasible from conventional time series graphical representations. Methods We introduce a simple-to-implement visualisation method, termed dynamical density delay mapping (“D3-Map” technique) that provides an animated representation of a system’s dynamics. The method is based on a generalization of conventional two-dimensional (2D) Poincaré plots, which are scatter plots where each data point, x(n), in a time series is plotted against the adjacent one, x(n + 1). First, we divide the original time series, x(n) (n = 1,…, N), into a sequence of segments (windows). Next, for each segment, a three-dimensional (3D) Poincaré surface plot of x(n), x(n + 1), h[x(n),x(n + 1)] is generated, in which the third dimension, h, represents the relative frequency of occurrence of each (x(n),x(n + 1)) point. This 3D Poincaré surface is then chromatised by mapping the relative frequency h values onto a colour scheme. We also generate a colourised 2D contour plot from each time series segment using the same colourmap scheme as for the 3D Poincaré surface. Finally, the original time series graph, the colourised 3D Poincaré surface plot, and its projection as a colourised 2D contour map for each segment, are animated to create the full “D3-Map.” Results We first exemplify the D3-Map method using the cardiac interbeat interval time series from a healthy subject during sleeping hours. The animations uncover complex dynamical changes, such as transitions between states, and the relative amount of time the system spends in each state. We also illustrate the utility of the method in detecting hidden temporal patterns in the heart rate dynamics of a patient with atrial fibrillation. The videos, as well as the source code, are made publicly available. Conclusions Animations based on density delay maps provide a new way of visualising dynamical properties of complex systems not apparent in time series graphs or standard Poincaré plot representations. Trainees in a variety of fields may find the animations useful as illustrations of fundamental but challenging concepts, such as nonstationarity and multistability. For investigators, the method may facilitate data exploration. PMID:24438439

Fast quantum nD Fourier and radon transforms

NASA Astrophysics Data System (ADS)

Labunets, Valeri G.; Labunets-Rundblad, Ekaterina V.; Astola, Jaakko T.

2001-07-01

Fast Classical and quantum algorithms are introduced for a wide class of non-separable nD discrete unitary K- transforms(DKT)KNn. They require a number of 1D DKT Kn smaller than in the Cooley-Tukey radix-p FFT-type approach. The method utilizes a decomposition of the nDK- transform into a product of original nD discrete Radon Transform and of a family parallel/independ 1DK-transforms. If the nDK-transform has a separable kernel, that again in this case our approach leads to decrease of multiplicative complexity by factor of n compared to the tow/column separable Cooley-Tukey p-radix approach.

Polyhedral realizations of crystal bases for quantum algebras of classical affine types

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoshino, A.

2013-05-15

We give the explicit forms of the crystal bases B({infinity}) for the quantum affine algebras of types A{sub 2n-1}{sup (2)}, A{sub 2n}{sup (2)}, B{sub n}{sup (1)}, C{sub n}{sup (1)}, D{sub n}{sup (1)}, and D{sub n+1}{sup (2)} by using the method of polyhedral realizations of crystal bases.

Cloning Sequencing and Structural Manipulation of the Enterotoxin D and E Genes from Staphylococcus aureus

DTIC Science & Technology

1990-07-01

Iandolo, J.J. and R.K. Tweten. 1988. Purification of staphylococcal enterotoxin. In. Methods of Enzymology, (N.O. Kaplan , S. Harshman, Eds.) volume 165...N C V 9 L G 0 K 1 S P A K I C T S N 0 149 "T7AACTGG&&C&hICG&clhht:7caflCATGTAATAa~aI ACca CAACaCAA 942 L K D G D K L Z L I G T P r D H K V N 0 H L..L

Estimation of Slow Crack Growth Parameters for Constant Stress-Rate Test Data of Advanced Ceramics and Glass by the Individual Data and Arithmetic Mean Methods

NASA Technical Reports Server (NTRS)

Choi, Sung R.; Salem, Jonathan A.; Holland, Frederic A.

1997-01-01

The two estimation methods, individual data and arithmetic mean methods, were used to determine the slow crack growth (SCG) parameters (n and D) of advanced ceramics and glass from a large number of room- and elevated-temperature constant stress-rate ('dynamic fatigue') test data. For ceramic materials with Weibull modulus greater than 10, the difference in the SCG parameters between the two estimation methods was negligible; whereas, for glass specimens exhibiting Weibull modulus of about 3, the difference was amplified, resulting in a maximum difference of 16 and 13 %, respectively, in n and D. Of the two SCG parameters, the parameter n was more sensitive to the estimation method than the other. The coefficient of variation in n was found to be somewhat greater in the individual data method than in the arithmetic mean method.

NMR investigation and theoretical calculations of the solvent effect on the conformation of valsartan

NASA Astrophysics Data System (ADS)

Chashmniam, Saeed; Tafazzoli, Mohsen

2017-11-01

Structure and conformational properties of valsartan were studied by advanced NMR techniques and quantum calculation methods. Potential energy scanning using B3LYP/6-311++g** and B3LYP-D3/6-311++g** methods were performed and four conformers (V1-V4) at minimum points of PES diagram were observed. According to the NMR spectra in acetone-d6, there are two conformers (M and m) with m/M = 0.52 ratio simultaneously and energy barriers of the two conformers were predicted from chemical shifts and multiplicities. While, intramolecular hydrogen bond at tetrazole ring and carboxylic groups prevent the free rotation on N6sbnd C11 bond in M-conformer, this bond rotates freely in m-conformer. On the other hand, intramolecular hydrogen bond at carbonyl and carboxylic acid can be observed at m-conformer. So, different intramolecular hydrogen bond is the reason for the stability of both M and m structures. Quite interestingly, 1H NMR spectra in CDCl3 show two distinct conformers (N and n) with unequal ratio which are differ from M-m conformers. Also, intramolecular hydrogen bond seven-member ring involving five-membered tetrazole ring and carboxylic acid group observed in both N and n-conformers Solvent effect, by using a set of polar and non-polar solvents including DMSO-d6, methanol-d4, benzene-d6, THF-d8, nitromethane-d3, methylene chloride-d2 and acetonitrile-d3 were investigated. NMR parameters include chemical shifts and spin-spin coupling constants were obtained from a set of 2D NMR spectra (H-H COSY, HMQC and HMBC). For this purpose, several DFT functionals from LDA, GGA and hybrid categories were used which the hybrid method showed better agreement with experiment values.

Superfast algorithms of multidimensional discrete k-wave transforms and Volterra filtering based on superfast radon transform

NASA Astrophysics Data System (ADS)

Labunets, Valeri G.; Labunets-Rundblad, Ekaterina V.; Astola, Jaakko T.

2001-12-01

Fast algorithms for a wide class of non-separable n-dimensional (nD) discrete unitary K-transforms (DKT) are introduced. They need less 1D DKTs than in the case of the classical radix-2 FFT-type approach. The method utilizes a decomposition of the nD K-transform into the product of a new nD discrete Radon transform and of a set of parallel/independ 1D K-transforms. If the nD K-transform has a separable kernel (e.g., the case of the discrete Fourier transform) our approach leads to decrease of multiplicative complexity by the factor of n comparing to the classical row/column separable approach. It is well known that an n-th order Volterra filter of one dimensional signal can be evaluated by an appropriate nD linear convolution. This work describes new superfast algorithm for Volterra filtering. New approach is based on the superfast discrete Radon and Nussbaumer polynomial transforms.

On the use of a Euclidean norm function for the estimation of local dynamic stability from 3D kinematics using time-delayed Lyapunov analyses.

PubMed

Beaudette, Shawn M; Howarth, Samuel J; Graham, Ryan B; Brown, Stephen H M

2016-10-01

Several different state-space reconstruction methods have been employed to assess the local dynamic stability (LDS) of a 3D kinematic system. One common method is to use a Euclidean norm (N) transformation of three orthogonal x, y, and z time-series' followed by the calculation of the maximum finite-time Lyapunov exponent (λmax) from the resultant N waveform (using a time-delayed state space reconstruction technique). By essentially acting as a weighted average, N has been suggested to account for simultaneous expansion and contraction along separate degrees of freedom within a 3D system (e.g. the coupling of dynamic movements between orthogonal planes). However, when estimating LDS using N, non-linear transformations inherent within the calculation of N should be accounted for. Results demonstrate that the use of N on 3D time-series data with arbitrary magnitudes of relative bias and zero-crossings cause the introduction of error in estimates of λmax obtained through N. To develop a standard for the analysis of 3D dynamic kinematic waveforms, we suggest that all dimensions of a 3D signal be independently shifted to avoid the incidence of zero-crossings prior to the calculation of N and subsequent estimation of LDS through the use of λmax. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

A fast calibration method for 3-D tracking of ultrasound images using a spatial localizer.

PubMed

Pagoulatos, N; Haynor, D R; Kim, Y

2001-09-01

We have developed a fast calibration method for computing the position and orientation of 2-D ultrasound (US) images in 3-D space where a position sensor is mounted on the US probe. This calibration is required in the fields of 3-D ultrasound and registration of ultrasound with other imaging modalities. Most of the existing calibration methods require a complex and tedious experimental procedure. Our method is simple and it is based on a custom-built phantom. Thirty N-fiducials (markers in the shape of the letter "N") embedded in the phantom provide the basis for our calibration procedure. We calibrated a 3.5-MHz sector phased-array probe with a magnetic position sensor, and we studied the accuracy and precision of our method. A typical calibration procedure requires approximately 2 min. We conclude that we can achieve accurate and precise calibration using a single US image, provided that a large number (approximately ten) of N-fiducials are captured within the US image, enabling a representative sampling of the imaging plane.

3 d printing of 2 d N=(0,2) gauge theories

NASA Astrophysics Data System (ADS)

Franco, Sebastián; Hasan, Azeem

2018-05-01

We introduce 3 d printing, a new algorithm for generating 2 d N=(0,2) gauge theories on D1-branes probing singular toric Calabi-Yau 4-folds using 4 d N=1 gauge theories on D3-branes probing toric Calabi-Yau 3-folds as starting points. Equivalently, this method produces brane brick models starting from brane tilings. 3 d printing represents a significant improvement with respect to previously available tools, allowing a straightforward determination of gauge theories for geometries that until now could only be tackled using partial resolution. We investigate the interplay between triality, an IR equivalence between different 2 d N=(0,2) gauge theories, and the freedom in 3 d printing given an underlying Calabi-Yau 4-fold. Finally, we present the first discussion of the consistency and reduction of brane brick models.

n-SIFT: n-dimensional scale invariant feature transform.

PubMed

Cheung, Warren; Hamarneh, Ghassan

2009-09-01

We propose the n-dimensional scale invariant feature transform (n-SIFT) method for extracting and matching salient features from scalar images of arbitrary dimensionality, and compare this method's performance to other related features. The proposed features extend the concepts used for 2-D scalar images in the computer vision SIFT technique for extracting and matching distinctive scale invariant features. We apply the features to images of arbitrary dimensionality through the use of hyperspherical coordinates for gradients and multidimensional histograms to create the feature vectors. We analyze the performance of a fully automated multimodal medical image matching technique based on these features, and successfully apply the technique to determine accurate feature point correspondence between pairs of 3-D MRI images and dynamic 3D + time CT data.

A fast Chebyshev method for simulating flexible-wing propulsion

NASA Astrophysics Data System (ADS)

Moore, M. Nicholas J.

2017-09-01

We develop a highly efficient numerical method to simulate small-amplitude flapping propulsion by a flexible wing in a nearly inviscid fluid. We allow the wing's elastic modulus and mass density to vary arbitrarily, with an eye towards optimizing these distributions for propulsive performance. The method to determine the wing kinematics is based on Chebyshev collocation of the 1D beam equation as coupled to the surrounding 2D fluid flow. Through small-amplitude analysis of the Euler equations (with trailing-edge vortex shedding), the complete hydrodynamics can be represented by a nonlocal operator that acts on the 1D wing kinematics. A class of semi-analytical solutions permits fast evaluation of this operator with O (Nlog ⁡ N) operations, where N is the number of collocation points on the wing. This is in contrast to the minimum O (N2) cost of a direct 2D fluid solver. The coupled wing-fluid problem is thus recast as a PDE with nonlocal operator, which we solve using a preconditioned iterative method. These techniques yield a solver of near-optimal complexity, O (Nlog ⁡ N) , allowing one to rapidly search the infinite-dimensional parameter space of all possible material distributions and even perform optimization over this space.

Measurement of the Neutron Flux of the Reaction C$sup 12$(d,n)N$sup 13$ Based on the Activity of N$sup 13$. Report No. 28; MEDICION DEL FLUJO NEUTRONICO DE LA REACCION C$sup 12$(d,n)N$sup 13$ A BASE DE LA ACTIVIDAD DEL N$sup 13$. INFORME NO 28

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keller, A.

1960-08-01

The principal problem in the measurement of neutron flux from the reaction C/sup 12/(d,n)N/sup 13/, based on the activity of N/sup 13/, is the possibility of nitrogen escape. A method for the measurement of possibie N/sup 13/ losses is described, and measurements with TiC targets irradiated with 600- kev deuterons are reported. The formulas for the calculation of the neutron flux are indicated. (tr-auth)

Localization of a variational particle smoother

NASA Astrophysics Data System (ADS)

Morzfeld, M.; Hodyss, D.; Poterjoy, J.

2017-12-01

Given the success of 4D-variational methods (4D-Var) in numerical weather prediction,and recent efforts to merge ensemble Kalman filters with 4D-Var,we consider a method to merge particle methods and 4D-Var.This leads us to revisit variational particle smoothers (varPS).We study the collapse of varPS in high-dimensional problemsand show how it can be prevented by weight-localization.We test varPS on the Lorenz'96 model of dimensionsn=40, n=400, and n=2000.In our numerical experiments, weight localization prevents the collapse of the varPS,and we note that the varPS yields results comparable to ensemble formulations of 4D-variational methods,while it outperforms EnKF with tuned localization and inflation,and the localized standard particle filter.Additional numerical experiments suggest that using localized weights in varPS may not yield significant advantages over unweighted or linearizedsolutions in near-Gaussian problems.

Reductive amination-assisted quantitation of tamoxifen and its metabolites by liquid phase chromatography tandem mass spectrometry.

PubMed

Liang, Shih-Shin; Wang, Tsu-Nai; Chiu, Chien-Chih; Kuo, Po-Lin; Huang, Mei-Fang; Liu, Meng-Chieh; Tsai, Eing-Mei

2016-02-19

Tamoxifen, a hormonal therapy drug against estrogen receptor-positive breast cancer, can be metabolized by cytochrome P450 enzymes such as CYP3A4 and CYP3A5, and converted to N-desmethyltamoxifen, which is subsequently, metabolized by CYP2D6 and inverted to form 4-hydroxy-N-desmethyltamoxifen (endoxifen). Conventional mass spectrometry (MS) analyses of tamoxifen and its metabolites require isotopic internal standards (ISs). In this study, endoxifen and N-desmethyltamoxifen amine groups were modified by reductive amination with formaldehyde-D2 to produce new metabolite molecules. Both endoxifen and N-desmethyltamoxifen generated their corresponding D2-methyl modified analogs. This method is expected to simplify MS detection and overcome the difficulty in selecting adequate ISs when tamoxifen metabolites are analyzed by absolute quantification. It identified tamoxifen, D2-methyl modified endoxifen, and D2-methyl modified N-desmethyltamoxifen with a linearity ranging from 2 to 5000 ng/mL with correlation coefficient (R(2)) values of 0.9868, 0.9849, and 0.9880, respectively. Furthermore, this reductive amination-based method may enhance the signal intensities of D2-methyl modified N-desmethyltamoxifen and endoxifen, thus facilitating the MS detection. Copyright © 2016 Elsevier B.V. All rights reserved.

0D/2D Z-Scheme Heterojunctions of Bismuth Tantalate Quantum Dots/Ultrathin g-C3N4 Nanosheets for Highly Efficient Visible Light Photocatalytic Degradation of Antibiotics.

PubMed

Wang, Kai; Zhang, Gaoke; Li, Jun; Li, Yuan; Wu, Xiaoyong

2017-12-20

Constructing 0D/2D Z-scheme photocatalysts is a great promising path to improve photocatalytic activity by  efficiently enhancing charge separation. Herein, we fabricated a visible-light-responsive Bi 3 TaO 7 quantum dots (QDs)/g-C 3 N 4 nanosheets (NSs) 0D/2D Z-scheme composite via a facile ultrasound method, and Bi 3 TaO 7 QDs could be interspersed on the surface of g-C 3 N 4 NSs uniformly. Furthermore, the strong interaction between Bi 3 TaO 7 QDs and g-C 3 N 4 NSs disturbed the CN heterocycles by forming C═O bonds between C atoms of the N-(C) 3 group and O atoms of the Ta-O bond. The optimum composite with 20 wt % g-C 3 N 4 NSs showed the superior photocatalytic activity for degradation of ciprofloxacin (CIP) over the composites prepared by mechanical mixing and solid-state methods, the photocatalytic efficiency of which were 4 and 12.2 times higher than those of bare Bi 3 TaO 7 and g-C 3 N 4 . Photoluminescence (PL), time-resolved transient PL decay spectra, and photocurrent together verify that the photogenerated hole-electron pairs in this 0D/2D Z-scheme composite have been effectively separated. The enhanced photocatalytic activity of as-synthesized photocatalysts could be attributed to the synergistic effect of efficient Z-scheme charge separation, highly dispersed 0D Bi 3 TaO 7 nanocrystals, coordinating sites of 2D g-C 3 N 4 NSs and the strong coupling between them. This study might pave the way toward designing novel visible-light-induced 0D/2D photocatalyst systems for highly efficient degradation of antibiotics.

Tensor numerical methods in quantum chemistry: from Hartree-Fock to excitation energies.

PubMed

Khoromskaia, Venera; Khoromskij, Boris N

2015-12-21

We resume the recent successes of the grid-based tensor numerical methods and discuss their prospects in real-space electronic structure calculations. These methods, based on the low-rank representation of the multidimensional functions and integral operators, first appeared as an accurate tensor calculus for the 3D Hartree potential using 1D complexity operations, and have evolved to entirely grid-based tensor-structured 3D Hartree-Fock eigenvalue solver. It benefits from tensor calculation of the core Hamiltonian and two-electron integrals (TEI) in O(n log n) complexity using the rank-structured approximation of basis functions, electron densities and convolution integral operators all represented on 3D n × n × n Cartesian grids. The algorithm for calculating TEI tensor in a form of the Cholesky decomposition is based on multiple factorizations using algebraic 1D "density fitting" scheme, which yield an almost irreducible number of product basis functions involved in the 3D convolution integrals, depending on a threshold ε > 0. The basis functions are not restricted to separable Gaussians, since the analytical integration is substituted by high-precision tensor-structured numerical quadratures. The tensor approaches to post-Hartree-Fock calculations for the MP2 energy correction and for the Bethe-Salpeter excitation energies, based on using low-rank factorizations and the reduced basis method, were recently introduced. Another direction is towards the tensor-based Hartree-Fock numerical scheme for finite lattices, where one of the numerical challenges is the summation of electrostatic potentials of a large number of nuclei. The 3D grid-based tensor method for calculation of a potential sum on a L × L × L lattice manifests the linear in L computational work, O(L), instead of the usual O(L(3) log L) scaling by the Ewald-type approaches.

Grid-based lattice summation of electrostatic potentials by assembled rank-structured tensor approximation

NASA Astrophysics Data System (ADS)

Khoromskaia, Venera; Khoromskij, Boris N.

2014-12-01

Our recent method for low-rank tensor representation of sums of the arbitrarily positioned electrostatic potentials discretized on a 3D Cartesian grid reduces the 3D tensor summation to operations involving only 1D vectors however retaining the linear complexity scaling in the number of potentials. Here, we introduce and study a novel tensor approach for fast and accurate assembled summation of a large number of lattice-allocated potentials represented on 3D N × N × N grid with the computational requirements only weakly dependent on the number of summed potentials. It is based on the assembled low-rank canonical tensor representations of the collected potentials using pointwise sums of shifted canonical vectors representing the single generating function, say the Newton kernel. For a sum of electrostatic potentials over L × L × L lattice embedded in a box the required storage scales linearly in the 1D grid-size, O(N) , while the numerical cost is estimated by O(NL) . For periodic boundary conditions, the storage demand remains proportional to the 1D grid-size of a unit cell, n = N / L, while the numerical cost reduces to O(N) , that outperforms the FFT-based Ewald-type summation algorithms of complexity O(N3 log N) . The complexity in the grid parameter N can be reduced even to the logarithmic scale O(log N) by using data-sparse representation of canonical N-vectors via the quantics tensor approximation. For justification, we prove an upper bound on the quantics ranks for the canonical vectors in the overall lattice sum. The presented approach is beneficial in applications which require further functional calculus with the lattice potential, say, scalar product with a function, integration or differentiation, which can be performed easily in tensor arithmetics on large 3D grids with 1D cost. Numerical tests illustrate the performance of the tensor summation method and confirm the estimated bounds on the tensor ranks.

One-step synthesis of 2D-layered carbon wrapped transition metal nitrides from transition metal carbides (MXenes) for supercapacitors with ultrahigh cycling stability.

PubMed

Yuan, Wenyu; Cheng, Laifei; Wu, Heng; Zhang, Yani; Lv, Shilin; Guo, Xiaohui

2018-03-13

A novel one-step method to synthesize 2D carbon wrapped TiN (C@TiN) was proposed via using 2D metal carbides (MXenes) as precursors. This study provides a novel approach to synthesize carbon wrapped metal nitrides.

Quantitative determination of free D-Asp, L-Asp and N-methyl-D-aspartate in mouse brain tissues by chiral separation and Multiple Reaction Monitoring tandem mass spectrometry.

PubMed

Fontanarosa, Carolina; Pane, Francesca; Sepe, Nunzio; Pinto, Gabriella; Trifuoggi, Marco; Squillace, Marta; Errico, Francesco; Usiello, Alessandro; Pucci, Piero; Amoresano, Angela

2017-01-01

Several studies have suggested that free d-Asp has a crucial role in N-methyl d-Asp receptor-mediated neurotransmission playing very important functions in physiological and pathological processes. This paper describes the development of an analytical procedure for the direct and simultaneous determination of free d-Asp, l-Asp and N-methyl d-Asp in specimens of different mouse brain tissues using chiral LC-MS/MS in Multiple Reaction Monitoring scan mode. After comparing three procedures and different buffers and extraction solvents, a simple preparation procedure was selected the analytes of extraction. The method was validated by analyzing l-Asp, d-Asp and N-methyl d-Asp recovery at different spiked concentrations (50, 100 and 200 pg/μl) yielding satisfactory recoveries (75-110%), and good repeatability. Limits of detection (LOD) resulted to be 0.52 pg/μl for d-Asp, 0.46 pg/μl for l-Asp and 0.54 pg/μl for NMDA, respectively. Limits of quantification (LOQ) were 1.57 pg/μl for d-Asp, 1.41 pg/μl for l-Asp and 1.64 pg/μl for NMDA, respectively. Different concentration levels were used for constructing the calibration curves which showed good linearity. The validated method was then successfully applied to the simultaneous detection of d-Asp, l-Asp and NMDA in mouse brain tissues. The concurrent, sensitive, fast, and reproducible measurement of these metabolites in brain tissues will be useful to correlate the amount of free d-Asp with relevant neurological processes, making the LC-MS/MS MRM method well suited, not only for research work but also for clinical analyses.

A Wideband Fast Multipole Method for the two-dimensional complex Helmholtz equation

NASA Astrophysics Data System (ADS)

Cho, Min Hyung; Cai, Wei

2010-12-01

A Wideband Fast Multipole Method (FMM) for the 2D Helmholtz equation is presented. It can evaluate the interactions between N particles governed by the fundamental solution of 2D complex Helmholtz equation in a fast manner for a wide range of complex wave number k, which was not easy with the original FMM due to the instability of the diagonalized conversion operator. This paper includes the description of theoretical backgrounds, the FMM algorithm, software structures, and some test runs. Program summaryProgram title: 2D-WFMM Catalogue identifier: AEHI_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHI_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 4636 No. of bytes in distributed program, including test data, etc.: 82 582 Distribution format: tar.gz Programming language: C Computer: Any Operating system: Any operating system with gcc version 4.2 or newer Has the code been vectorized or parallelized?: Multi-core processors with shared memory RAM: Depending on the number of particles N and the wave number k Classification: 4.8, 4.12 External routines: OpenMP ( http://openmp.org/wp/) Nature of problem: Evaluate interaction between N particles governed by the fundamental solution of 2D Helmholtz equation with complex k. Solution method: Multilevel Fast Multipole Algorithm in a hierarchical quad-tree structure with cutoff level which combines low frequency method and high frequency method. Running time: Depending on the number of particles N, wave number k, and number of cores in CPU. CPU time increases as N log N.

Synthesis of N-peptide-6-amino-D-luciferin Conjugates.

PubMed

Kovács, Anita K; Hegyes, Péter; Szebeni, Gábor J; Nagy, Lajos I; Puskás, László G; Tóth, Gábor K

2018-01-01

A general strategy for the synthesis of N -peptide-6-amino-D-luciferin conjugates has been developed. The applicability of the strategy was demonstrated with the preparation of a known substrate, N -Z-Asp-Glu-Val-Asp-6-amino-D-luciferin ( N -Z-DEVD-aLuc). N -Z-DEVD-aLuc was obtained via a hybrid liquid/solid phase synthesis method, in which the appropriately protected C-terminal amino acid was coupled to 6-amino-2-cyanobenzothiazole and the resulting conjugate was reacted with D-cysteine in order to get the protected amino acid-6-amino-D-luciferin conjugate, which was then attached to resin. The resulting loaded resin was used for the solid-phase synthesis of the desired N -peptide-6-amino-D-luciferin conjugate without difficulties, which was then attested with NMR spectroscopy and LC-MS, and successfully tested in a bioluminescent system.

Synthesis of N-peptide-6-amino-D-luciferin Conjugates

PubMed Central

Kovács, Anita K.; Hegyes, Péter; Szebeni, Gábor J.; Nagy, Lajos I.; Puskás, László G.; Tóth, Gábor K.

2018-01-01

A general strategy for the synthesis of N-peptide-6-amino-D-luciferin conjugates has been developed. The applicability of the strategy was demonstrated with the preparation of a known substrate, N-Z-Asp-Glu-Val-Asp-6-amino-D-luciferin (N-Z-DEVD-aLuc). N-Z-DEVD-aLuc was obtained via a hybrid liquid/solid phase synthesis method, in which the appropriately protected C-terminal amino acid was coupled to 6-amino-2-cyanobenzothiazole and the resulting conjugate was reacted with D-cysteine in order to get the protected amino acid-6-amino-D-luciferin conjugate, which was then attached to resin. The resulting loaded resin was used for the solid-phase synthesis of the desired N-peptide-6-amino-D-luciferin conjugate without difficulties, which was then attested with NMR spectroscopy and LC-MS, and successfully tested in a bioluminescent system. PMID:29725588

-HPLC determination of acidic d-amino acids and their N-methyl derivatives in biological tissues

PubMed Central

Tsesarskaia, Mara; Galindo, Erika; Szókán, Gyula; Fisher, George

2015-01-01

d-aspartate (d-Asp) and N-methyl-d-aspartate (NMDA) occur in the neuroendocrine systems of vertebrates and invertebrates where they play a role in hormone release and synthesis, neurotransmission, and memory and learning. N-methyl-d-glutamate (NMDG) has also been detected in marine bivalves. Several methods have been used to detect these amino acids, but they require pretreatment of tissue samples with o-phthaldialdehyde (OPA) to remove primary amino acids which interfere with the detection of NMDA and NMDG. We report here a one step derivatization procedure with the chiral reagent N-α-(5-fluoro-2,4-dinitrophenyl)-(d or l)-valine amide, FDNP-Val-NH2, a close analog of Marfey’s reagent but with better resolution and higher molar absorptivity. The diastereomers formed are separated by HPLC on an ODS-Hypersil column eluted with TFA/water – TFA/MeCN. UV absorption at 340 nm permits detection levels as low as 5–10 picomoles. D-Asp, NMDA and NMDG peaks are not obscured by other primary or secondary amino acids; hence pretreatment of tissues with OPA is not required. This method is highly reliable and fast (less than 40 minutes HPLC run). Using this method, we have detected D-Asp, NMDA and NMDG in several biological tissues (octopus brain, optical lobe, and bucchal mass; foot and mantle of the mollusk Scapharca broughtonii), confirming the results of other researchers. PMID:19277955

Accurate D-bar Reconstructions of Conductivity Images Based on a Method of Moment with Sinc Basis.

PubMed

Abbasi, Mahdi

2014-01-01

Planar D-bar integral equation is one of the inverse scattering solution methods for complex problems including inverse conductivity considered in applications such as Electrical impedance tomography (EIT). Recently two different methodologies are considered for the numerical solution of D-bar integrals equation, namely product integrals and multigrid. The first one involves high computational burden and the other one suffers from low convergence rate (CR). In this paper, a novel high speed moment method based using the sinc basis is introduced to solve the two-dimensional D-bar integral equation. In this method, all functions within D-bar integral equation are first expanded using the sinc basis functions. Then, the orthogonal properties of their products dissolve the integral operator of the D-bar equation and results a discrete convolution equation. That is, the new moment method leads to the equation solution without direct computation of the D-bar integral. The resulted discrete convolution equation maybe adapted to a suitable structure to be solved using fast Fourier transform. This allows us to reduce the order of computational complexity to as low as O (N (2)log N). Simulation results on solving D-bar equations arising in EIT problem show that the proposed method is accurate with an ultra-linear CR.

Accurate prediction of bond dissociation energies of large n-alkanes using ONIOM-CCSD(T)/CBS methods

NASA Astrophysics Data System (ADS)

Wu, Junjun; Ning, Hongbo; Ma, Liuhao; Ren, Wei

2018-05-01

Accurate determination of the bond dissociation energies (BDEs) of large alkanes is desirable but practically impossible due to the expensive cost of high-level ab initio methods. We developed a two-layer ONIOM-CCSD(T)/CBS method which treats the high layer with CCSD(T) method and the low layer with DFT method, respectively. The accuracy of this method was validated by comparing the calculated BDEs of n-hexane with that obtained at the CCSD(T)-F12b/aug-cc-pVTZ level of theory. On this basis, the C-C BDEs of C6-C20 n-alkanes were calculated systematically using the ONIOM [CCSD(T)/CBS(D-T):M06-2x/6-311++G(d,p)] method, showing a good agreement with the data available in the literature.

RATE CONSTANTS FOR THE REACTIONS OF OH RADICALS AND CL ATOMS WITH DI-N-PROPYL ETHER AND DI-N-BUTYL ETHER AND THEIR DEUTERATED ANALOGS. (R825252)

EPA Science Inventory

Using relative rate methods, rate constants for the gas-phase reactions of OH radicals and Cl atoms with di-n-propyl ether, di-n-propyl ether-d₁₄, di-n-butyl ether and di-n-butyl ether-d₁₈ have been measured at 296 ? 2 K and atmos...

Analysis of concentration and (13)C enrichment of D-galactose in human plasma.

PubMed

Schadewaldt, P; Hammen, H W; Loganathan, K; Bodner-Leidecker, A; Wendel, U

2000-05-01

A stable-isotope dilution method for the sensitive determination of D-galactose in human plasma was established. D-[(13)C]Galactose was added to plasma, and the concentration was measured after D-glucose was removed from the plasma by treatment with D-glucose oxidase and the sample was purified by ion-exchange chromatography. For gas chromatographic-mass spectrometric analysis, aldononitrile pentaacetate derivatives were prepared. Monitoring of the [MH-60](+) ion intensities at m/z 328, 329, and 334 in the positive chemical ionization mode allowed the assessment of 1-(12)C-, 1-(13)C-, and U-(13)C(6)-labeled D-galactose, respectively. The D-galactose concentration was quantified on the basis of the (13)C-labeled internal standard. The method was linear (range examined, 0.1-5 micromol/L) and of good repeatability in the low and high concentration ranges (within- and between-run CVs <15%). The limit of quantification for plasma D-galactose was <0.02 micromol/L. Measurements in plasma of postabsorptive subjects yielded D-galactose concentrations (mean +/- SD) of 0.12 +/- 0.03 (n = 16), 0.11 +/- 0.04 (n = 15), 1.44 +/- 0.54 (n = 10), and 0.17 +/- 0.07 (n = 5) micromol/L in healthy adults, diabetic patients, patients with classical galactosemia, and obligate heterozygous parents thereof, respectively. These data were considerably lower (3- to 18-fold) than the values of a conventional enzymatic assay. The procedure was also applied successfully in a stable-isotope turnover study to evaluate endogenous D-galactose formation. The present findings establish that detection of D-galactose from endogenous sources is feasible in human plasma and show that erroneously high results may be obtained by enzymatic methods.

State Space Methods in Multidimensional Digital Signal Processing

DTIC Science & Technology

1991-01-01

2-D finite difference equation with quarter-plane support is given by [1]. Li L-2 Ll L2 g (nln2) =E E Zb(jl,j2)f(n,-j, n 2 -j 2 ) - E a(jl,j2) g (n, - j...B2 [ g (n , n2)] = [C1 C2 1 Sq’(n nl2) ]+ D [f (ni, n 2 )] (2.2) Roesser’s state space model is based upon assigning state variables to the output of...QH(n - 1,n2) + [ B1 [f(nl,n2)]Qv(ni, n2) I A3 A411 Qv(nl, n2 -1 1 B2 [ g (n 1 ,n 2 )] = [C1 C 2] Q(n - n) + D[f(nin 2 )] (2.5) I Qv(ni,n2- 1) 1 In this

Accuracy and reliability of coronal and sagittal spinal curvature data based on patient-specific three-dimensional models created by the EOS 2D/3D imaging system.

PubMed

Somoskeöy, Szabolcs; Tunyogi-Csapó, Miklós; Bogyó, Csaba; Illés, Tamás

2012-11-01

Three-dimensional (3D) deformations of the spine are predominantly characterized by two-dimensional (2D) angulation measurements in coronal and sagittal planes, using anteroposterior and lateral X-ray images. For coronal curves, a method originally described by Cobb and for sagittal curves a modified Cobb method are most widely used in practice, and these methods have been shown to exhibit good-to-excellent reliability and reproducibility, carried out either manually or by computer-based tools. Recently, an ultralow radiation dose-integrated radioimaging solution was introduced with special software for realistic 3D visualization and parametric characterization of the spinal column. Comparison of accuracy, correlation of measurement values, intraobserver and interrater reliability of methods by conventional manual 2D and sterEOS 3D measurements in a routine clinical setting. Retrospective nonrandomized study of diagnostic X-ray images created as part of a routine clinical protocol of eligible patients examined at our clinic during a 30-month period between July 2007 and December 2009. In total, 201 individuals (170 females, 31 males; mean age, 19.88 years) including 10 healthy athletes with normal spine and patients with adolescent idiopathic scoliosis (175 cases), adult degenerative scoliosis (11 cases), and Scheuermann hyperkyphosis (5 cases). Overall range of coronal curves was between 2.4° and 117.5°. Analysis of accuracy and reliability of measurements were carried out on a group of all patients and in subgroups based on coronal plane deviation: 0° to 10° (Group 1, n=36), 10° to 25° (Group 2, n=25), 25° to 50° (Group 3, n=69), 50° to 75° (Group 4, n=49), and more than 75° (Group 5, n=22). Coronal and sagittal curvature measurements were determined by three experienced examiners, using either traditional 2D methods or automatic measurements based on sterEOS 3D reconstructions. Manual measurements were performed three times, and sterEOS 3D reconstructions and automatic measurements were performed two times by each examiner. Means comparison t test, Pearson bivariate correlation analysis, reliability analysis by intraclass correlation coefficients for intraobserver reproducibility and interrater reliability were performed using SPSS v16.0 software (IBM Corp., Armonk, NY, USA). No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this article. In comparison with manual 2D methods, only small and nonsignificant differences were detectable in sterEOS 3D-based curvature data. Intraobserver reliability was excellent for both methods, and interrater reproducibility was consistently higher for sterEOS 3D methods that was found to be unaffected by the magnitude of coronal curves or sagittal plane deviations. This is the first clinical report on EOS 2D/3D system (EOS Imaging, Paris, France) and its sterEOS 3D software, documenting an excellent capability for accurate, reliable, and reproducible spinal curvature measurements. Copyright © 2012 Elsevier Inc. All rights reserved.

Pretrichodermamides D-F from a Marine Algicolous Fungus Penicillium sp. KMM 4672.

PubMed

Yurchenko, Anton N; Smetanina, Olga F; Ivanets, Elena V; Kalinovsky, Anatoly I; Khudyakova, Yuliya V; Kirichuk, Natalya N; Popov, Roman S; Bokemeyer, Carsten; von Amsberg, Gunhild; Chingizova, Ekaterina A; Afiyatullov, Shamil Sh; Dyshlovoy, Sergey A

2016-06-27

Three new epidithiodiketopiperazines pretrichodermamides D-F (1-3), together with the known N-methylpretrichodermamide B (4) and pretrichodermamide С (5), were isolated from the lipophilic extract of the marine algae-derived fungus Penicillium sp. KMM 4672. The structures of compounds 1-5 were determined based on spectroscopic methods. The absolute configuration of pretrichodermamide D (1) was established by a combination of modified Mosher's method, NOESY data, and biogenetic considerations. N-Methylpretrichodermamide B (5) showed strong cytotoxicity against 22Rv1 human prostate cancer cells resistant to androgen receptor targeted therapies.

Quantification of 3-nitrobenzanthrone-DNA adducts using online column-switching HPLC-electrospray tandem mass spectrometry.

PubMed

Gamboa da Costa, Gonçalo; Singh, Rajinder; Arlt, Volker M; Mirza, Amin; Richards, Meirion; Takamura-Enya, Takeji; Schmeiser, Heinz H; Farmer, Peter B; Phillips, David H

2009-11-01

The aromatic nitroketone 3-nitrobenzanthrone (3-nitro-7H-benz[de]anthracen-7-one; 3-NBA) is an extremely potent mutagen and a suspected human carcinogen detected in the exhaust of diesel engines and in airborne particulate matter. 3-NBA is metabolically activated via reduction of the nitro group to the hydroxylamine (N-OH-3-ABA) to form covalent DNA adducts. Thus far, the detection and quantification of covalent 3-NBA-DNA adducts has relied solely on (32)P-postlabeling methodologies. In order to expand the range of available techniques for the detection and improved quantification of 3-NBA-DNA adducts, we have developed a method based upon online column-switching HPLC coupled to electrospray tandem mass spectrometry, with isotopic dilution of (15)N-labeled internal standards. This methodology was applied to the determination of three 3-NBA-derived adducts: 2-(2'-deoxyguanosin-N(2)-yl)-3-aminobenzanthrone (dG-N(2)-3-ABA), N-(2'-deoxyguanosin-8-yl)-3-aminobenzanthrone (dG-C8-N-3-ABA) and 2-(2'-deoxyguanosine-8-yl)-3-aminobenzanthrone (dG-C8-C2-3-ABA). Dose-dependent increases were observed for all three adducts when salmon testis DNA was reacted with N-acetoxy-3-aminobenzanthrone (N-AcO-3-ABA). dG-C8-C2-3-ABA was detected at much lower levels (overall 1%) than the other two adducts. DNA samples isolated from tissues of rats treated either intratracheally with 3-NBA or intraperitoneally with N-OH-3-ABA were analyzed by mass spectrometry, and the results compared to those obtained by (32)P-postlabeling. The method required 50 microg of hydrolyzed animal DNA on column and the limit of detection was 2.0 fmol for each adduct. dG-C8-C2-3-ABA was not observed in any of the samples providing confirmation that it is not formed in vivo. Linear regression analysis of the levels of dG-N(2)-3-ABA and dG-C8-N-3-ABA in the rat DNA showed a reasonable correlation between the two methods (R(2) = 0.88 and 0.93, respectively). In summary, the mass spectrometric method is a faster, more automated analytical approach that also provides structural confirmation of the adducts detected by (32)P-postlabeling, and it has sufficient sensitivity and precision to analyze DNA adducts in animals exposed to 3-NBA or its hydroxylamine metabolite.

Design of two-dimensional zero reference codes with cross-entropy method.

PubMed

Chen, Jung-Chieh; Wen, Chao-Kai

2010-06-20

We present a cross-entropy (CE)-based method for the design of optimum two-dimensional (2D) zero reference codes (ZRCs) in order to generate a zero reference signal for a grating measurement system and achieve absolute position, a coordinate origin, or a machine home position. In the absence of diffraction effects, the 2D ZRC design problem is known as the autocorrelation approximation. Based on the properties of the autocorrelation function, the design of the 2D ZRC is first formulated as a particular combination optimization problem. The CE method is then applied to search for an optimal 2D ZRC and thus obtain the desirable zero reference signal. Computer simulation results indicate that there are 15.38% and 14.29% reductions in the second maxima value for the 16x16 grating system with n(1)=64 and the 100x100 grating system with n(1)=300, respectively, where n(1) is the number of transparent pixels, compared with those of the conventional genetic algorithm.

Recording 13C-15N HMQC 2D sparse spectra in solids in 30 s

NASA Astrophysics Data System (ADS)

Kupče, Ēriks; Trébosc, Julien; Perrone, Barbara; Lafon, Olivier; Amoureux, Jean-Paul

2018-03-01

We propose a dipolar HMQC Hadamard-encoded (D-HMQC-Hn) experiment for fast 2D correlations of abundant nuclei in solids. The main limitation of the Hadamard methods resides in the length of the encoding pulses, which results from a compromise between the selectivity and the sensitivity due to losses. For this reason, these methods should mainly be used with sparse spectra, and they profit from the increased separation of the resonances at high magnetic fields. In the case of the D-HMQC-Hn experiments, we give a simple rule that allows directly setting the optimum length of the selective pulses, versus the minimum separation of the resonances in the indirect dimension. The demonstration has been performed on a fully 13C,15N labelled f-MLF sample, and it allowed recording the build-up curves of the 13C-15N cross-peaks within 10 min. However, the method could also be used in the case of less sensitive samples, but with more accumulations.

Three-dimensional ghost imaging lidar via sparsity constraint

NASA Astrophysics Data System (ADS)

Gong, Wenlin; Zhao, Chengqiang; Yu, Hong; Chen, Mingliang; Xu, Wendong; Han, Shensheng

2016-05-01

Three-dimensional (3D) remote imaging attracts increasing attentions in capturing a target’s characteristics. Although great progress for 3D remote imaging has been made with methods such as scanning imaging lidar and pulsed floodlight-illumination imaging lidar, either the detection range or application mode are limited by present methods. Ghost imaging via sparsity constraint (GISC), enables the reconstruction of a two-dimensional N-pixel image from much fewer than N measurements. By GISC technique and the depth information of targets captured with time-resolved measurements, we report a 3D GISC lidar system and experimentally show that a 3D scene at about 1.0 km range can be stably reconstructed with global measurements even below the Nyquist limit. Compared with existing 3D optical imaging methods, 3D GISC has the capability of both high efficiency in information extraction and high sensitivity in detection. This approach can be generalized in nonvisible wavebands and applied to other 3D imaging areas.

A Floating Potential Method for Determining Ion Density

NASA Astrophysics Data System (ADS)

Evans, John D.; Chen, Francis F.

2001-10-01

The density n in partially ionized discharges is often found from the saturation ion current Ii of a cylindrical Langmuir probe. Collisionless probe theories, however, disagree with measured I - V curves probably because of collisions^1. We use a heuristic method that yields n from probe data agreeing with microwave interferometry. Probe current I is raised to the 4/3 power and fitted to a straight line on an I^4/3-V plot. The line is extrapolated to the floating potential V_f, thus approximating I_i(V_f). The sheath thickness d_sh for V = Vf is calculated from the Child-Langmuir (CL) law, and applying the Bohm sheath criterion to the surface at r_sh = Rp + d_sh yields n when Ii = I_i(V_f). This method works, but it cannot be justified by theory. Neglected are (a) cylindrical convergence of the ion charge, (b) finite ion energy at r = r_sh, (c) ions orbiting the probe, and (d) escape of ions axially. The Allen-Boyd-Reynolds theory, which treats (a) and (b) and neglects (c) and (d), gives too low n's. Apparently the errors self-cancel, and the simple Vf method gives the right result. ^1 F.F. Chen, Phys. Plasmas 8, 3029 (2001).

The Transcorrelated Method Combined with the Variational Monte Carlo Calculation: Application to Atoms

NASA Astrophysics Data System (ADS)

Umezawa, Naoto; Tsuneyuki, Shinji; Ohno, Takahisa; Shiraishi, Kenji; Chikyow, Toyohiro

2005-03-01

The transcorrelated (TC) method is a useful approach to optimize the Jastrow-Slater-type many-body wave function FD. The basic idea of the TC method [1] is based on the similarity transformation of a many-body Hamiltonian H with respect to the Jastrow factor F: HTC=frac1F H F in order to incorporate the correlation effect into HTC. Both the F and D are optimized by minimizing the variance ^2=|Hrm TCD - E D |^2 d^3N x. The optimization for F is implemented by the variational Monte Carlo calculation, and D is determined by the TC self-consistent-field equation for the one-body wave functions φμ(x), which is derived from the functional derivative of ^2 with respect to φmu(x). In this talk, we will present the results given by the transcorrelated variational Monte Carlo (TC-VMC) method for the ground state [2] and the excited states of atoms [3]. [1]S. F. Boys and N. C. Handy, Proc. Roy. Soc. A, 309, 209; 310, 43; 310, 63; 311, 309 (1969). [2]N. Umezawa and S. Tsuneyuki, J. Chem. Phys. 119, 10015 (2003). [3]N. Umezawa and S. Tsuneyuki, J. Chem. Phys. 121, 7070 (2004).

Three-dimensional modeling of n+-nu-n+ and p+-pi-p+ semiconducting devices for analog ULSI microelectronics

NASA Astrophysics Data System (ADS)

Gillet, Jean-Numa; Degorce, Jean-Yves; Belisle, Jonathan; Meunier, Michel

2004-03-01

Three-dimensional modeling of n^+-ν -n^+ and p^+-π -p^+ semiconducting devices for analog ULSI microelectronics Jean-Numa Gillet,^a,b Jean-Yves Degorce,^a Jonathan Bélisle^a and Michel Meunier.^a,c ^a École Polytechnique de Montréal, Dept. of Engineering Physics, CP 6079, Succ. Centre-vile, Montréal, Québec H3C 3A7, Canada. ^b Corresponding author. Email: Jean-Numa.Gillet@polymtl.ca ^c Also with LTRIM Technologies, 140-440, boul. A.-Frappier, Laval, Québec H7V 4B4, Canada. We present for the first time three-dimensional (3-D) modeling of n^+-ν -n^+ and p^+-π -p^+ semiconducting resistors, which are fabricated by laser-induced doping in a gateless MOSFET and present significant applications for analog ULSI microelectronics. Our modeling software is made up of three steps. The two first concerns modeling of a new laser-trimming fabrication process. With the molten-silicon temperature distribution obtained from the first, we compute in the second the 3-D dopant distribution, which creates the electrical link through the device gap. In this paper the emphasis is on the third step, which concerns 3-D modeling of the resistor electronic behavior with a new tube multiplexing algorithm (TMA). The device current-voltage (I-V) curve is usually obtained by solving three coupled partial differential equations with a finite-element method. A 3-D device as our resistor cannot be modeled with this classical method owing to its prohibitive computational cost in three dimensions. This problem is however avoided by our TMA, which divides the 3-D device into one-dimensional (1-D) multiplexed tubes. In our TMA 1-D systems of three ordinary differential equations are solved to determine the 3-D device I-V curve, which substantially increases computation speed compared with the classical method. Numerical results show a good agreement with experiments.

Symplocin A, a Linear Peptide from the Bahamian Cyanobacterium Symploca sp. Configurational Analysis of N,N-Dimethylamino Acids by Chiral-Phase HPLC of Naphthacyl Esters†

PubMed Central

Molinski, Tadeusz F.; Reynolds, Kirk A.; Morinaka, Brandon I.

2012-01-01

The absolute stereostructures of the components of symplocin A (3), a new N,N-dimethyl-terminated peptide from the Bahamian cyanobacterium, Symploca sp., were assigned from spectroscopic analysis, including MS and 2D NMR and Marfey’s analysis. The complete absolute configuration of symplocin A, including the unexpected D-configurations of the terminal N,N-dimethylisoleucine and valic acid residues, were assigned by chiral-phase HPLC of the corresponding 2-naphthacyl esters, a highly sensitive, complementary strategy for assignment of N-blocked peptide residues where Marfey’s method is ineffectual, or other methods fall short. Symplocin A exhibited potent activity as an inhibitor of cathepsin E (IC50 300 pM). PMID:22360587

Chemical constituents and biological activities of Dianthus elegans var. elegans.

PubMed

Mutlu, Kiymet; Sarikahya, Nazli Boke; Nalbantsoy, Ayse; Kirmizigul, Suheyla

2018-06-01

Chemical investigation of the aerial parts of Dianthus elegans var. elegans afforded two previously undescribed saponins, named dianosides M-N (1-2), together with four oleanane-type triterpenoid glycosides (3-6). Their structures were elucidated as 3-O-α-L-arabinofuranosyl-16α-hydroxyolean-12-ene-23α, 28β-dioic acid (1) and 3-O-α-L-arabinofuranosyl-(1 → 3)-β-D-glucopyranosyl 16α-hydroxyolean-12-ene-23α-oic acid, 28-O-β-D-glucopyranosyl-(1 → 6)-β-D-glycosyl ester (2) by chemical and extensive spectroscopic methods including IR, 1D, 2D NMR and HRESIMS. Both of the saponins were evaluated for their cytotoxicities against HEK-293, A-549 and HeLa human cancer cells using the MTT method. All compounds showed no substantial cytotoxic activity against tested cell lines. However, dianosides M-N and the n-butanol fraction exhibited considerable haemolysis in human erythrocyte cells. The immunomodulatory properties of dianosides M-N were also evaluated in activated whole blood cells by PMA plus ionomycin. Dianosides M-N increased IL-1β concentration significantly whereas the n-butanol fraction slightly augmented IL-1β secretion. All compounds did not change IL-2 and IFN-γ levels considerably.

Comparison of a bioassay and a liquid chromatography-fluorescence-mass spectrometry(n) method for the detection of incurred enrofloxacin residues in chicken tissues.

PubMed

Schneider, M J; Donoghue, D J

2004-05-01

Regulatory monitoring for most antibiotic residues in edible poultry tissues is often accomplished with accurate, although expensive and technically demanding, chemical analytical techniques. The purpose of this study is to determine if a simple, inexpensive bioassay could detect fluoroquinolone (FQ) residues in chicken muscle above the FDA established tolerance (300 ppb) comparable to a liquid chromatography-fluorescencemass spectrometry(n) method. To produce incurred enrofloxacin (ENRO) tissues (where ENRO is incorporated into complex tissue matrices) for the method comparison, 40-d-old broilers (mixed sex) were orally dosed through drinking water for 3 d at the FDA-approved dose of ENRO (50 ppm). At the end of each day of the 3-d dosing period and for 3 d postdosing, birds were sacrificed and breast and thigh muscle collected and analyzed. Both methods were able to detect ENRO at and below the tolerance level in the muscle, with limits of detection of 26 ppb (bioassay), 0.1 ppb for ENRO, and 0.5 ppb for the ENRO metabolite, ciprofloxacin (liquid chromatography-fluorescence-mass spectrometry(n)). All samples that had violative levels of antibiotic were detected by the bioassay. These results support the use of this bioassay as a screening method for examining large numbers of samples for regulatory monitoring. Positive samples should then be examined by a more extensive method, such as liquid chromatography-fluorescence-mass spectrometry(n), to provide confirmation of the analyte.

Fast Collaborative Filtering from Implicit Feedback withProvable Guarantees

DTIC Science & Technology

2016-11-22

n2 = Ω (( ε d̃2sσK(M2) )2) • n3 = Ω ( K2 ( 10 d̃2sσK(M2)5/2 + 2 √ 2 d̃3sσK(M2)3/2 )2 ε2 ) 212 Fast Collaborative Filtering for some constants c1 and c2...drawback of Method of Moments is that it will not work when there are only a few users available such that N < Θ( K2 ). However, modern recommendation systems...2 √ 2 d̃3sσK(M2)3/2 ) 2ε√ N ≤ c1 1 K √ πmax Since πmax ≤ 1, we need N ≥ Ω ( K2 ( 10 d̃2sσK(M2)5/2 + 2 √ 2 d̃3sσK(M2)3/2 )2 ε2 ) . This con- tributes

Evaluation of the DNA damaging potential of cannabis cigarette smoke by the determination of acetaldehyde derived N2-ethyl-2'-deoxyguanosine adducts.

PubMed

Singh, Rajinder; Sandhu, Jatinderpal; Kaur, Balvinder; Juren, Tina; Steward, William P; Segerbäck, Dan; Farmer, Peter B

2009-06-01

Acetaldehyde is an ubiquitous genotoxic compound that has been classified as a possible carcinogen to humans. It can react with DNA to form primarily a Schiff base N(2)-ethylidene-2'-deoxyguanosine (N(2)-ethylidene-dG) adduct. An online column-switching valve liquid chromatography tandem mass spectrometry (LC-MS/MS) selected reaction monitoring (SRM) method was developed for the determination of N(2)-ethylidene-dG adducts in DNA following reduction with sodium cyanoborohydride (NaBH(3)CN) to the chemically stable N(2)-ethyl-2'-deoxyguanosine (N(2)-ethyl-dG) adduct. Accurate quantitation of the adduct was obtained by the addition of the [(15)N(5)]N(2)-ethyl-dG stable isotope-labeled internal standard prior to enzymatic hydrolysis of the DNA samples to 2'-deoxynucleosides with the incorporation of NaBH(3)CN in the DNA hydrolysis buffer. The method required 50 microg of hydrolyzed DNA on column for the analysis, and the limit of detection for N(2)-ethyl-dG was 2.0 fmol. The analysis of calf thymus DNA treated in vitro with acetaldehyde (ranging from 0.5 to 100 mM) or with the smoke generated from 1, 5, and 10 cannabis cigarettes showed linear dose-dependent increases in the level of N(2)-ethyl-dG adducts (r = 0.954 and r = 0.999, respectively). Similar levels (332.8 +/- 21.9 vs 348.4 +/- 19.1 adducts per 10(8) 2'-deoxynucleosides) of N(2)-ethyl-dG adducts were detected following the exposure of calf thymus DNA to 10 tobacco or 10 cannabis cigarettes. No significant difference was found in the levels of N(2)-ethyl-dG adducts in human lung DNA obtained from nonsmokers (n = 4) and smokers (n = 4) with the average level observed as 13.3 +/- 0.7 adducts per 10(8) 2'-deoxynucleosides. No N(2)-ethyl-dG adducts were detected in any of the DNA samples following analysis with the omission of NaBH(3)CN from the DNA hydrolysis buffer. In conclusion, these results provide evidence for the DNA damaging potential of cannabis smoke, implying that the consumption of cannabis cigarettes may be detrimental to human health with the possibility to initiate cancer development.

CORRELATIONS OF EFFECTIVE TEMPERATURES FOR NEUTRON SPECTRA EMITTED IN U$sup 235$ AND Pu$sup 239$ FISSION BY FAST AND SLOW NEUTRONS (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smirenkin, G.M.

1959-12-01

The method of threshold indicators was used for determining the magnitude of dT/sub ef//dE/sub n/. The fission neutrons were produced by fast and slow neutron bombardment. tron bombardment was accomplished in a paraffin block. Hollow metallic U/sup 235/ (90% enriched) and Pu/sup 239/ specimens with 50 mm outside diameters and 10 mm thick contained the threshold activator Ag/sup 107/(n,2n)Ag/sup 106m/. Measurements were made of the neutron flux above the threshold (9.5 Mev) of the Ag/sup 107/(n,2n)Ag/sup 106m/ reaction and the number of fission in the sphere (N/sub gamma /). The final data showed that for U/sup 235/ dT/sub ef//dE/sub n/more » = 0.008 plus or minus 0.004 and for Pu/sup 239/ dT/ sub ef/ /dE/sub n/ = tron fission distributions explain part of the error of the measurement. (R.V.J.)« less

Comparison and Concordance of Academic Air Force Officer Qualifying Test, SAT, and ACT Scores among Air Force ROTC Cadets

DTIC Science & Technology

2013-05-01

N A E P -Q A S co rin g S p ecial S tu d y F Y 0 5 — D R A F T REPORT DOCUMENTATION PAGE Form...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 iv N A E P -Q A S co rin g S p ecial S tu d y F Y 0 5 — D R A F T...admissions. 3 N A E P -Q A S co rin g S p ecial S tu d y F Y 0 5 — D R A F T Method

Compound-specific nitrogen isotope analysis of D-alanine, L-alanine, and valine: application of diastereomer separation to delta15N and microbial peptidoglycan studies.

PubMed

Takano, Yoshinori; Chikaraishi, Yoshito; Ogawa, Nanako O; Kitazato, Hiroshi; Ohkouchi, Naohiko

2009-01-01

We have developed an analytical method to determine the compound-specific nitrogen isotope compositions of individual amino acid enantiomers using gas chromatography/combustion/isotope ratio mass spectrometry. A novel derivatization of amino acid diastereomers by optically active (R)-(-)-2-butanol or (S)-(+)-2-butanol offers two advantages for nitrogen isotope analysis. First, chromatographic chiral separation can be achieved without the use of chiral stationary-phase columns. Second, the elution order of these compounds on the chromatogram can be switched by a designated esterification reaction. We applied the method to the compound-specific nitrogen isotope analysis of D- and L-alanine in a peptidoglycan derived from the cell walls of cultured bacteria (Firmicutes and Actinobacteria; Enterococcus faecalis, Staphylococcus aureus, Staphylococcus staphylolyticus, Lactobacillus acidophilus, Bacillus subtilis, Micrococcus luteus, and Streptomyces sp.), natural whole bacterial cells (Bacillus subtilis var. natto), (pseudo)-peptidoglycan from archaea (Methanobacterium sp.), and cell wall from eukaryota (Saccharomyces cerevisiae). We observed statistically significant differences in nitrogen isotopic compositions; e.g., delta15N ( per thousand vs air) in Staphylococcus staphylolyticus for d-alanine (19.2 +/- 0.5 per thousand, n = 4) and L-alanine (21.3 +/- 0.8 per thousand, n = 4) and in Bacillus subtilis for D-alanine (6.2 +/- 0.2 per thousand, n = 3) and L-alanine (8.2 +/- 0.4 per thousand, n = 3). These results suggest that enzymatic reaction pathways, including the alanine racemase reaction, produce a nitrogen isotopic difference in amino acid enantiomers, resulting in 15N-depleted D-alanine. This method is expected to facilitate compound-specific nitrogen isotope studies of amino acid stereoisomers.

[Determination of equilibrium solubility and n-octanol/water partition coefficient of pulchinenosiden D by HPLC].

PubMed

Rao, Xiao-Yong; Yin, Shan; Zhang, Guo-Song; Luo, Xiao-Jian; Jian, Hui; Feng, Yu-Lin; Yang, Shi-Lin

2014-05-01

To determine the equilibrium solubility of pulchinenosiden D in different solvents and its n-octanol/water partition coefficients. Combining shaking flask method and high performance liquid chromatography (HPLC) to detect the n-octanol/water partition coefficients of pulchinenosiden D, the equilibrium solubility of pulchinenosiden D in six organic solvents and different pH buffer solution were determined by HPLC analysis. n-Octanol/water partition coefficients of pulchinenosiden D in different pH were greater than zero, the equilibrium solubility of pulchinenosiden D was increased with increase the pH of the buffer solution. The maximum equilibrium solubility of pulchinenosiden D was 255.89 g x L(-1) in methanol, and minimum equilibrium solubility of pulchinenosiden D was 0.20 g x L(-1) in acetonitrile. Under gastrointestinal physiological conditions, pulchinenosiden D exists in molecular state and it has good absorption but poor water-solubility, so increasing the dissolution rate of pulchinenosiden D may enhance its bioavailability.

Fast reconstruction of off-axis digital holograms based on digital spatial multiplexing.

PubMed

Sha, Bei; Liu, Xuan; Ge, Xiao-Lu; Guo, Cheng-Shan

2014-09-22

A method for fast reconstruction of off-axis digital holograms based on digital multiplexing algorithm is proposed. Instead of the existed angular multiplexing (AM), the new method utilizes a spatial multiplexing (SM) algorithm, in which four off-axis holograms recorded in sequence are synthesized into one SM function through multiplying each hologram with a tilted plane wave and then adding them up. In comparison with the conventional methods, the SM algorithm simplifies two-dimensional (2-D) Fourier transforms (FTs) of four N*N arrays into a 1.25-D FTs of one N*N arrays. Experimental results demonstrate that, using the SM algorithm, the computational efficiency can be improved and the reconstructed wavefronts keep the same quality as those retrieved based on the existed AM method. This algorithm may be useful in design of a fast preview system of dynamic wavefront imaging in digital holography.

Experimentally-based ExB drifts in the DIII-D divertor and SOL calculated from integration of Ohm's law using Thomson scattering measurements of T e and n e

DOE PAGES

Stangeby, Peter C.; Elder, J. David; McLean, Adam G.; ...

2017-03-27

We calculated the 2D spatial distributions of cross field drift velocities from 2D Thomson scattering measurements of T e and n e in the divertor and SOL of DIII-D. In contrast with the method that has been used on DIII-D where the 2D distribution of plasma potential V plasma is obtained from measurements of the probe floating potential of reciprocating probes, the present method does not require insertion of a probe into the plasma and can therefore be used in high power discharges. Furthermore, the 2D spatial distribution of V plasma is calculated from Ohm’s Law for the parallel electricmore » field E || along each flux tube, E || s || = -1.71dT e/ds || - T e/n edn e/ds ||, where the Thomson scattering values of T e and n e are used. To within a constant of integration, V plasma is obtained by integrating E || along the flux-tubes (field lines); the constant is obtained for each flux tube using the sheath drop at the target calculated from the characteristic of Langmuir probes built into the divertor tiles. The 2D distributions of E./01/2 = -dV4/ds./01/2, E452510/2 = -dV4/ds452510/2, v789 452510/2 = E./01/2/B and v789 ./01/2 = E452510/2/B are then calculated as well as the particle drift flux densities Γ789 452510/2 = nv789 452510/2 and Γ789 ./01/2 = nv789 ./01/2 for electrons, fuel ions and impurity ions, using the appropriate values of particle density, n.« less

Experimentally-based ExB drifts in the DIII-D divertor and SOL calculated from integration of Ohm's law using Thomson scattering measurements of T e and n e

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stangeby, Peter C.; Elder, J. David; McLean, Adam G.

We calculated the 2D spatial distributions of cross field drift velocities from 2D Thomson scattering measurements of T e and n e in the divertor and SOL of DIII-D. In contrast with the method that has been used on DIII-D where the 2D distribution of plasma potential V plasma is obtained from measurements of the probe floating potential of reciprocating probes, the present method does not require insertion of a probe into the plasma and can therefore be used in high power discharges. Furthermore, the 2D spatial distribution of V plasma is calculated from Ohm’s Law for the parallel electricmore » field E || along each flux tube, E || s || = -1.71dT e/ds || - T e/n edn e/ds ||, where the Thomson scattering values of T e and n e are used. To within a constant of integration, V plasma is obtained by integrating E || along the flux-tubes (field lines); the constant is obtained for each flux tube using the sheath drop at the target calculated from the characteristic of Langmuir probes built into the divertor tiles. The 2D distributions of E./01/2 = -dV4/ds./01/2, E452510/2 = -dV4/ds452510/2, v789 452510/2 = E./01/2/B and v789 ./01/2 = E452510/2/B are then calculated as well as the particle drift flux densities Γ789 452510/2 = nv789 452510/2 and Γ789 ./01/2 = nv789 ./01/2 for electrons, fuel ions and impurity ions, using the appropriate values of particle density, n.« less

Denitrification and nitrogen transport in a coastal aquifer receiving wastewater discharge

USGS Publications Warehouse

DeSimone, L.A.; Howes, B.L.

1996-01-01

Denitrification and nitrogen transport were quantified in a sandy glacial aquifer receiving wastewater from a septage-treatment facility on Cape Cod, MA. The resulting groundwater plume contained high concentrations of NO3- (32 mg of NL-1), total dissolved nitrogen (40.5 mg of N L-1), and dissolved organic carbon (1.9 mg of C L-1) and developed a central anoxic zone after 17 months of effluent discharge. Denitrifying activity was measured using four approaches throughout the major biogeochemical zones of the plume. Three approaches that maintained the structure of aquifer materials yielded comparable rates: acetylene block in intact sediment cores, 9.6 ng of N cm-3 d-1 (n = 61); in situ N2 production, 3.0 ng of N cm-3 d-1 (n = 11); and in situ NO3- depletion, 7.1 ng of N cm-3 d-1 (n = 3). In contrast, the mixing of aquifer materials using a standard slurry method yielded rates that were more than 15-fold higher (150 ng of N cm-3 d-1, n = 16) than other methods. Concentrations and ??15N of groundwater and effluent N2, NO3-, and NH4+ were consistent with the lower rates of denitrification determined by the intact-core or in situ methods. These methods and a plumewide survey of excess N2 indicate that 2-9% of the total mass of fixed nitrogen recharged to the anoxic zone of the plume was denitrified during the 34-month study period. Denitrification was limited by organic carbon (not NO3-) concentrations, as evidenced by a nitrate and carbon addition experiment, the correlation of denitrifying activity with in situ concentrations of dissolved organic carbon, and the assessments of available organic carbon in plume sediments. Carbon limitation is consistent with the observed conservative transport of 85-96% of the nitrate in the anoxic zone. Although denitrifying activity removed a significant amount (46250 kg) of fixed nitrogen during transport, the effects of aquifer denitrification on the nitrogen load to receiving ecosystems are likely to be small (<10%).

All-optical Integrated Switches Based on Azo-benzene Liquid Crystals on Silicon

DTIC Science & Technology

2011-11-01

Glass D263 SU8 Polymer Polymer NLC n̂ n̂ Refractive index @1.55 µm Materials n// = 1.689 n⊥= 1.502 n = 1.575 n = 1.516 E7 Glass D263 SU8 ...In the other case we have a nonlinear LCW based on glass substrates. It consists in a rectangular hollow realized in SU8 photoresist two glass...and discussion 5. All optical polymeric waveguide: methods, assumptions and procedure 6. All optical polymeric waveguide: results and discussion 7

Intermolecular dissociation energies of dispersively bound complexes of aromatics with noble gases and nitrogen

NASA Astrophysics Data System (ADS)

Knochenmuss, Richard; Sinha, Rajeev K.; Leutwyler, Samuel

2018-04-01

We measured accurate intermolecular dissociation energies D0 of the supersonic jet-cooled complexes of 1-naphthol (1NpOH) with the noble gases Ne, Ar, Kr, and Xe and with N2, using the stimulated-emission pumping resonant two-photon ionization method. The ground-state values D0(S0) for the 1NpOHṡS complexes with S= Ar, Kr, Xe, and N2 were bracketed to be within ±3.5%; they are 5.67 ± 0.05 kJ/mol for S = Ar, 7.34 ± 0.07 kJ/mol for S = Kr, 10.8 ± 0.28 kJ/mol for S = Xe, 6.67 ± 0.08 kJ/mol for isomer 1 of the 1NpOHṡN2 complex, and 6.62 ± 0.22 kJ/mol for the corresponding isomer 2. For S = Ne, the upper limit is D0 < 3.36 kJ/mol. The dissociation energies increase by 1%-5% upon S0 → S1 excitation of the complexes. Three dispersion-corrected density functional theory (DFT-D) methods (B97-D3, B3LYP-D3, and ωB97X-D) predict that the most stable form of these complexes involves dispersive binding to the naphthalene "face." A more weakly bound edge isomer is predicted in which the S moiety is H-bonded to the OH group of 1NpOH; however, no edge isomers were observed experimentally. The B97-D3 calculated dissociation energies D0(S0) of the face complexes with Ar, Kr, and N2 agree with the experimental values within <5%, but the D0(S0) for Xe is 12% too low. The B3LYP-D3 and ωB97X-D calculated D0(S0) values exhibit larger deviations to both larger and smaller dissociation energies. For comparison to 1-naphthol, we calculated the D0(S0) of the carbazole complexes with S = Ne, Ar, Kr, Xe, and N2 using the same DFT-D methods. The respective experimental values have been previously determined to be within <2%. Again, the B97-D3 results are in the best overall agreement with experiment.

Optimal Conclusive Teleportation of an Arbitrary d-Dimensional N-Particle Unknown State via a Partially Entangled Quantum Channel

NASA Astrophysics Data System (ADS)

Hao, San-Ru; Hou, Bo-Yu; Xi, Xiao-Qiang; Yue, Rui-Hong

2003-02-01

In this paper we generalize the standard teleportation to the conclusive teleportation case which can teleport an arbitrary d-dimensional N-particle unknown state via the partially entangled quantum channel. We show that only if the quantum channel satisfies a constraint condition can the most general d-dimensional N-particle unknown state be perfect conclusively teleported. We also present a method for optimal conclusively teleportation of the N-particle states and for constructing the joint POVM which can discern the quantum states on the sender's (Alice's) side. Two typical examples are given so that one can see how our method works. The project supported in part by National Natural Science Foundation of China under Grant No. 19975036 and the Foundation of Science and Technology Committee of Hunan Province of China under Grant No. 21000205

Pressure-controlled terahertz filter based on 1D photonic crystal with a defective semiconductor

NASA Astrophysics Data System (ADS)

Qinwen, XUE; Xiaohua, WANG; Chenglin, LIU; Youwen, LIU

2018-03-01

The tunable terahertz (THz) filter has been designed and studied, which is composed of 1D photonic crystal (PC) containing a defect layer of semiconductor GaAs. The analytical solution of 1D defective PC (1DDPC) is deduced based on the transfer matrix method, and the electromagnetic plane wave numerical simulation of this 1DDPC is performed by using the finite element method. The calculated and simulated results have confirmed that the filtering transmittance of this 1DDPC in symmetric structure of air/(Si/SiO2) N /GaAs/(SiO2/Si) N /air is far higher than in asymmetric structure of air/(Si/SiO2) N /GaAs/(Si/SiO2) N /air, where the filtering frequency can be tuned by the external pressure. It can provide a feasible route to design the external pressure-controlled THz filter based on 1DPC with a defective semiconductor.

Moderate Bacterial Etching Allows Scalable and Clean Delamination of g-C3N4 with Enriched Unpaired Electrons for Highly Improved Photocatalytic Water Disinfection.

PubMed

Kang, Shifei; Huang, Wei; Zhang, Lu; He, Maofen; Xu, Suyun; Sun, Di; Jiang, Xia

2018-04-25

Delamination treatment is crucial in promoting the activity of bulk graphitic carbon nitride (g-C 3 N 4 ). However, most of the currently used methods of exfoliating bulk g-C 3 N 4 to achieve g-C 3 N 4 thin layers suffer from low yield and environmental pollution. Herein, we developed a facile bacterial etching approach for the preparation of high-quality g-C 3 N 4 nanosheets by exfoliating bulk g-C 3 N 4 under room temperature. Morphology and physicochemical characterizations show that the bacteria-treated g-C 3 N 4 (BT-CN) samples, especially BT-CN-2d, have a lamina-like two-dimensional (2D) in-plane porous structure, a significantly enlarged specific surface area (82.61 m 2 g -1 ), and a remarkable narrow band gap (2.11 eV). X-ray photoelectron spectroscopy and electron paramagnetic resonance spectra confirm the dramatic enrichment of unpaired electron in the BT-CN-2d g-C 3 N 4 nanosheets. EIS spectra and photocurrent tests indicate the fast electron transportation. As a result, the representative BT-CN-2d g-C 3 N 4 photocatalyst shows an optimal visible light-driven photocatalytic performance in water disinfection (fourfold higher than bulk g-C 3 N 4 ), as well as good cycle stability. This moderate and clean bacterial etching process can be realized in tens of gram scale in the laboratory and should be readily extended to kilogram scale. The present work provides fundamental knowledge about the scalable production of high-quality g-C 3 N 4 by bioengineering method, offering extendable availability for designing and fabricating other functional 2D materials.

Integrated Reconfigurable Intelligent Systems (IRIS) for Complex Naval Systems

DTIC Science & Technology

2010-02-21

RKF45] and Adams Variable Step- Size Predictor - Corrector methods). While such algorithms naturally are usually used to numerically solve differential...verified by yet another function call. Due to their nature, such methods are referred to as predictor - corrector methods. While computationally expensive...CONTRACT NUMBER N00014-09- C -0394 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER N/A 6. Author(s) Dr. Dimitri N. Mavris Dr. Yongchang Li 5d

Quanitfying atmospheric nitrogen loading to watersheds using nitrate isotopes (15N, 17O, 18O)

NASA Astrophysics Data System (ADS)

Wankel, S. D.; Kendall, C.

2002-12-01

Over the past century, human activity has greatly increased the amount of reactive nitrogen (N) in the atmosphere and the N inputs to terrestrial and aquatic ecosystems. Recent studies in the northeastern US have indicated that atmospheric N deposition is a significant source to land and water in the region, with contributions ranging from 15 to 60%. Estimates of the importance of atmospheric N have been plagued with uncertainty, however, due to incomplete data from atmospheric monitoring networks, to the varied spatial and temporal scales of databases dealing with agricultural, population, and land use, and to simplifications that are necessary to describe the complex rates of N accumulation and transformation. The principal objective of this study is the evaluation of new stable isotope techniques for quantifying the relative contributions atmospheric sources of anthropogenic nitrogen to the landscape and to the total N exported from watersheds in the northeastern US. In the last decade, several studies have used d18O and d15N of nitrate to evaluate the relative contributions of riverine nitrate derived from atmospheric sources. Very recent advances in analytical techniques (by Michalski, Thiemens, and colleagues) that allow the analysis of nitrate for d17O have shown that atmospheric nitrate is labeled with an anomalous, non-terrestrial, d17O signature. Hence, we now have three isotopes of nitrate that can be used to quantify sources of riverine nitrate. To test whether the analysis of nitrate for d17O enhances our ability to quantify atmospheric contributions to the total nitrate exported by major river basins, we have initiated a pilot study of many of the major rivers in the Ohio Basin and the northeastern USA. Published studies in these basins suggest that nitrate from basins dominated by urban, forested, and undeveloped landuses frequently has d18O values consistent with significant input from atmospheric sources. Preliminary d18O and d15N of nitrate data from these basins, generated using the new microbial denitrifier method developed by Sigman et al (2001) and Casciotti et al (in press), are in general agreement with published values. We are in the process of testing a modification of the Sigman-Casciotti method that will permit the additional analysis of nitrate from very small samples for d17O. The results of this new method along with a preliminary assessment of the data generated with our pilot study will be presented.

Study of Proximity Effect at D-Wave Superconductors in Quasiclassical Methods

NASA Astrophysics Data System (ADS)

Tanuma, Y.; Tanaka, Y.; Kashiwaya, S.

2005-08-01

Tunneling spectra via Andreev bound states between a normal metal (N) / dx2-y2-wave superconductor (S) (in the presence of a subdominant s-wave pair potential) junction are investigated. In the present work, in order to study the role of proximity effect, we employ quasiclassical Green's function methods. This merit is that we can determine the spatial variation of the pair potentials self-consistently, where the leaking of pair potentials into the N side is involved. In the N/S junction with orientational angle θ = π/4, we can regard as the isolated d-wave superconductor, where attractive interaction in the N side is negligible. On the other hand, in the case of a high transparent contact to the d-wave superconductor (θ = 0), the pair potential penetrates into the inside of the N due to the proximity effect, where the is-wave is not indued at all. Then, the tunneling spectra has a very sharp zero-energy peak (ZEP). This ZEP originates from the fact that quasiparticles feel different sign of the pair potentials between normal metals and d-wave superconductors through Andreev reflections. We show that the spatial dependence of pair potentials is significantly sensitive to the transparency of the junction.

Sufficient and necessary condition of separability for generalized Werner states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deng Dongling; Chen Jingling

2009-02-15

In a celebrated paper [Optics Communications 179, 447, 2000], A.O. Pittenger and M.H. Rubin presented for the first time a sufficient and necessary condition of separability for the generalized Werner states. Inspired by their ideas, we generalized their method to a more general case. We obtain a sufficient and necessary condition for the separability of a specific class of N d-dimensional system (qudits) states, namely special generalized Werner state (SGWS): W{sup [d{sup N}]}(v)=(1-v)(I{sup (N)})/(d{sup N}) +v|{psi}{sub d}{sup N}><{psi}{sub d}{sup N}|, where |{psi}{sub d}{sup N}>={sigma}{sub i=0}{sup d-1}{alpha}{sub i}|i...i> is an entangled pure state of N qudits system and {alpha}{sub i} satisfiesmore » two restrictions: (i) {sigma}{sub i=0}{sup d-1}{alpha}{sub i}{alpha}{sub i}*=1; (ii) Matrix 1/d (I{sup (1)}+T{sigma}{sub i{ne}}{sub j}{alpha}{sub i}|i>

Critical Two-Point Function for Long-Range O( n) Models Below the Upper Critical Dimension

NASA Astrophysics Data System (ADS)

Lohmann, Martin; Slade, Gordon; Wallace, Benjamin C.

2017-12-01

We consider the n-component |φ|^4 lattice spin model (n ≥ 1) and the weakly self-avoiding walk (n=0) on Z^d, in dimensions d=1,2,3. We study long-range models based on the fractional Laplacian, with spin-spin interactions or walk step probabilities decaying with distance r as r^{-(d+α )} with α \\in (0,2). The upper critical dimension is d_c=2α . For ɛ >0, and α = 1/2 (d+ɛ ), the dimension d=d_c-ɛ is below the upper critical dimension. For small ɛ , weak coupling, and all integers n ≥ 0, we prove that the two-point function at the critical point decays with distance as r^{-(d-α )}. This "sticking" of the critical exponent at its mean-field value was first predicted in the physics literature in 1972. Our proof is based on a rigorous renormalisation group method. The treatment of observables differs from that used in recent work on the nearest-neighbour 4-dimensional case, via our use of a cluster expansion.

On the two-loop divergences of the 2-point hypermultiplet supergraphs for 6D, N = (1 , 1) SYM theory

NASA Astrophysics Data System (ADS)

Buchbinder, I. L.; Ivanov, E. A.; Merzlikin, B. S.; Stepanyantz, K. V.

2018-03-01

We consider 6D, N = (1 , 1) supersymmetric Yang-Mills theory formulated in N = (1 , 0) harmonic superspace and analyze the structure of the two-loop divergences in the hypermultiplet sector. Using the N = (1 , 0) superfield background field method we study the two-point supergraphs with the hypermultiplet legs and prove that their total contribution to the divergent part of effective action vanishes off shell.

Comparison of HELIX TWT Simulation Using 2-D PIC (Magic), 2-D Modal (Gator), and 1-D Modal (Christine) Methods

DTIC Science & Technology

1998-05-01

Mission Research Corporation MRC/WDC-R-424 COMPARISON OF HELIX TWT SIMULATION USING 2-D PIC ( MAGIC ), 2-D MODAL (GATOR), AND 1-D MODAL (CHRISTINE...BRILLOUIN RUN 9 3.4 OUTLIER ELECTRON EFFECT IN GATOR 12 3.5 EMISSION CONDITION AND NONLAMINAR FLOW IN MAGIC 12 3.6 RADIAL SHEAR 13 SECTION 4. PPM B...Simulation using 2-D PIC ( MAGIC ), 2-D Modal (GATOR) and 1-D Modal (CHRISTINE) methods * D.N. Smithe(a), H. Freund(b), T. M. Antonsen Jr.,(b)’(c), E

Isotopomers as a method for differentiating between bacterial and fungal production of nitrous oxide

NASA Astrophysics Data System (ADS)

Sutka, R. L.; Adams, G.; Ostrom, N.; Ostrom, P.

2007-12-01

In order to study the importance of fungi to nitrous oxide (N2O) production in the environment it is critical to have a non-intrusive method for differentiating between fungal and bacterial N2O production. Site preference (SP), the difference in d15N between the central and outer N atoms in N2O, has been used to differentiate between bacterial nitrification and denitrification. In this study we compare the SP, d15N and d18O of N2O produced by the two best-studied fungal denitrifiers, Fusarium oxysporum and Cylindrocarpon tonkinense, to data from our previous bacterial studies. Both d18O and SP values remained fairly constant during the course of nitrite reduction which likely reflects isotopic exchange with water in the case of d18O and conservative behavior in SP that has been observed previously (Sutka et al., 2006). We observed a wide range of fractionation factors for fungal denitrification, -74.7 to -6.6 ‰, and non-linear behavior indicating that fractionation was controlled by more than one step. We interpret the small degree of fractionation as reflecting fractionation during diffusion and the more negative values as being controlled by enzymatic fractionation. Data from this and our previous study of bacterial production (Sutka et al., 2006) reveals that N2O produced via nitrification by fungi can be differentiated from N2O produced by bacterial denitrification primarily on the basis of d18O. The site preference of N2O produced by F. oxysporum and C. tonkinense was 37.1 ± 2.5 ‰ and 36.9 ± 2.8 ‰, respectively. These results indicate that isotopomers can be used as a basis for differentiating bacterial and fungal denitrification. Our work further reveals the role that fungal and bacterial nitric oxide reductases have in determining site preference during N2O production.

Multilevel Green's function interpolation method for scattering from composite metallic and dielectric objects.

PubMed

Shi, Yan; Wang, Hao Gang; Li, Long; Chan, Chi Hou

2008-10-01

A multilevel Green's function interpolation method based on two kinds of multilevel partitioning schemes--the quasi-2D and the hybrid partitioning scheme--is proposed for analyzing electromagnetic scattering from objects comprising both conducting and dielectric parts. The problem is formulated using the surface integral equation for homogeneous dielectric and conducting bodies. A quasi-2D multilevel partitioning scheme is devised to improve the efficiency of the Green's function interpolation. In contrast to previous multilevel partitioning schemes, noncubic groups are introduced to discretize the whole EM structure in this quasi-2D multilevel partitioning scheme. Based on the detailed analysis of the dimension of the group in this partitioning scheme, a hybrid quasi-2D/3D multilevel partitioning scheme is proposed to effectively handle objects with fine local structures. Selection criteria for some key parameters relating to the interpolation technique are given. The proposed algorithm is ideal for the solution of problems involving objects such as missiles, microstrip antenna arrays, photonic bandgap structures, etc. Numerical examples are presented to show that CPU time is between O(N) and O(N log N) while the computer memory requirement is O(N).

Efficient generation of holographic news ticker in holographic 3DTV

NASA Astrophysics Data System (ADS)

Kim, Seung-Cheol; Kim, Eun-Soo

2009-08-01

News ticker is used to show breaking news or news headlines in conventional 2-D broadcasting system. For the case of the breaking news, the fast creation is need, because the information should be sent quickly. In addition, if holographic 3- D broadcasting system is started in the future, news ticker will remain. On the other hands, some approaches for generation of CGH patterns have been suggested like the ray-tracing method and look-up table (LUT) method. However, these methods have some drawbacks that needs much time or needs huge memory size for look-up table. Recently, a novel LUT (N-LUT) method for fast generation of CGH patterns of 3-D objects with a dramatically reduced LUT without the loss of computational speed was proposed. Therefore, we proposed the method to efficiently generate the holographic news ticker in holographic 3DTV or 3-D movies using N-LUT method. The proposed method is largely consisted of five steps: construction of the LUT for each character, extraction of characters in news ticker, generation and shift of the CGH pattern for news ticker using the LUT for each character, composition of hologram pattern for 3-D video and hologram pattern for news ticker and reconstruct the holographic 3D video with news ticker. To confirm the proposed method, moving car in front of the castle is used as a 3D video and the words 'HOLOGRAM CAPTION GENERATOR' is used as a news ticker. From this simulation results confirmed the feasibility of the proposed method in fast generation of CGH patterns for holographic captions.

Precision and sensitivity of the measurement of 15N enrichment in D-alanine from bacterial cell walls using positive/negative ion mass spectrometry

NASA Technical Reports Server (NTRS)

Tunlid, A.; Odham, G.; Findlay, R. H.; White, D. C.

1985-01-01

Sensitive detection of cellular components from specific groups of microbes can be utilized as 'signatures' in the examination of microbial consortia from soils, sediments or biofilms. Utilizing capillary gas chromatography/mass spectrometry and stereospecific derivatizing agents, D-alanine, a component localized in the prokaryotic (bacterial) cell wall, can be detected reproducibly. Enrichments of D-[15N]alanine determined in E. coli grown with [15N]ammonia can be determined with precision at 1.0 atom%. Chemical ionization with methane gas and the detection of negative ions (M - HF)- and (M - F or M + H - HF)- formed from the heptafluorobutyryl D-2 butanol ester of D-alanine allowed as little as 8 pg (90 fmol) to be detected reproducibly. This method can be utilized to define the metabolic activity in terms of 15N incorporation at the level of 10(3)-10(4) cells, as a function of the 15N-14N ratio.

Stability theory applications to laminar-flow control

NASA Technical Reports Server (NTRS)

Malik, Mujeeb R.

1987-01-01

In order to design Laminar Flow Control (LFC) configurations, reliable methods are needed for boundary-layer transition predictions. Among the available methods, there are correlations based upon R sub e, shape factors, Goertler number and crossflow Reynolds number. The most advanced transition prediction method is based upon linear stability theory in the form of the e sup N method which has proven to be successful in predicting transition in two- and three-dimensional boundary layers. When transition occurs in a low disturbance environment, the e sup N method provides a viable design tool for transition prediction and LFC in both 2-D and 3-D subsonic/supersonic flows. This is true for transition dominated by either TS, crossflow, or Goertler instability. If Goertler/TS or crossflow/TS interaction is present, the e sup N will fail to predict transition. However, there is no evidence of such interaction at low amplitudes of Goertler and crossflow vortices.

Scanning method as an unbiased simulation technique and its application to the study of self-attracting random walks

NASA Astrophysics Data System (ADS)

Meirovitch, Hagai

1985-12-01

The scanning method proposed by us [J. Phys. A 15, L735 (1982); Macromolecules 18, 563 (1985)] for simulation of polymer chains is further developed and applied, for the first time, to a model with finite interactions. In addition to ``importance sampling,'' we remove the bias introduced by the scanning method with a procedure suggested recently by Schmidt [Phys. Rev. Lett. 51, 2175 (1983)]; this procedure has the advantage of enabling one to estimate the statistical error. We find these two procedures to be equally efficient. The model studied is an N-step random walk on a lattice, in which a random walk i has a statistical weight &, where p<1 is an attractive energy parameter and Mi is the number of distinct sites visited by walk i. This model, which corresponds to a model of random walks moving in a medium with randomly distributed static traps, has been solved analytically for N-->∞ for any dimension d by Donsker and Varadhan (DV) and by others. and lnφ, where φ is the survival probability in the trapping problem, diverge like Nα with α=d/(d+2). Most numerical studies, however, have failed to reach the DV regime in which d/(d+2) becomes a good approximation for α. On the other hand, our results for α (obtained for N<=150) are close to the DV values for p<=0.7 and p<=0.6 for d=2 and 3, respectively. This suggests that the scanning method is more efficient than both the commonly used direct Monte Carlo technique, and the Rosenbluth and Rosenbluth method [J. Chem. Phys. 23, 356 (1954)]. Our results support the conclusion of Havlin et al. [Phys. Rev. Lett. 53, 407 (1984)] that the DV regime exists already for φ<=10-13 for both d=2 and 3. We also find that at the percolation threshold pc the exponents for the end-to-end distance are small, but larger than zero, and that the probability of a walk returning to the origin behaves approximately as N-1/3 for both d=2 and 3.

Two-dimensional heterostructure materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geohegan, David B.; Rouleau, Christopher M.; Wang, Kai

Methods, articles of manufacture and systems for creating new nanoscale two dimensional materials comprising designed arrays of lateral or vertical heterojunctions may be fabricated by first lithographically masking a 2D material. Exposed, or unmasked, regions of the 2D material may be converted to a different composition of matter to form lateral or vertical heterojunctions according to the patterned mask. PLD and high kinetic energy impingement of atoms may replace or add atoms in the exposed regions, and a plurality of the exposed regions may be converted concurrently. The process may be repeated one or more times on either side ofmore » the same 2D material to form any suitable combination of lateral heterojunctions and/or vertical heterojunctions, comprising semiconductors, metals or insulators or any suitable combination thereof. Furthermore, the resulting 2D material may comprise p-n, n-n, p-p, n-p-n and p-n-p junctions, or any suitable combination thereof.« less

Improved Manufacturing Methods for Navy Peacoats

DTIC Science & Technology

1991-09-30

oaeration requir= S a heavy ;;erd, feed machine II n CC T is can e done either with a r I 2 .’" ark buttonhoie loc-tion with the I Ir fo I...AD-A243 702 F A S H I 0 N I INSTITUTE OF TECHNOLOGYI R E S EARCH DTIC I REPORT SELECTEI.. D D I IMPROVED MANUFACTURING METHODS FOR NAVY PEACOATS I I...A008. I IHenr A/Seesselberg Dir ctor, Advanced Apparel Manufacturing Technology Programs, Fashion Institute of Technology I Noah Bronner Research

Glycogen phosphorylase as a target for type 2 diabetes: synthetic, biochemical, structural and computational evaluation of novel N-acyl-N´-(β-D-glucopyranosyl) urea inhibitors.

PubMed

Kantsadi, Anastassia L; Parmenopoulou, Vanessa; Bakalov, Dimitar N; Snelgrove, Laura; Stravodimos, George A; Chatzileontiadou, Demetra S M; Manta, Stella; Panagiotopoulou, Angeliki; Hayes, Joseph M; Komiotis, Dimitri; Leonidas, Demetres D

2015-01-01

Glycogen phosphorylase (GP), a validated target for the development of anti-hyperglycaemic agents, has been targeted for the design of novel glycopyranosylamine inhibitors. Exploiting the two most potent inhibitors from our previous study of N-acyl-β-D-glucopyranosylamines (Parmenopoulou et al., Bioorg. Med. Chem. 2014, 22, 4810), we have extended the linking group to -NHCONHCO- between the glucose moiety and the aliphatic/aromatic substituent in the GP catalytic site β-cavity. The N-acyl-N´-(β-D-glucopyranosyl) urea inhibitors were synthesized and their efficiency assessed by biochemical methods, revealing inhibition constant values of 4.95 µM and 2.53 µM. Crystal structures of GP in complex with these inhibitors were determined and analyzed, providing data for further structure based design efforts. A novel Linear Response - Molecular Mechanics Coulomb Surface Area (LR-MM-CBSA) method has been developed which relates predicted and experimental binding free energies for a training set of N-acyl-N´-(β-D-glucopyranosyl) urea ligands with a correlation coefficient R(2) of 0.89 and leave-one-out cross-validation (LOO-cv) Q(2) statistic of 0.79. The method has significant applications to direct future lead optimization studies, where ligand entropy loss on binding is revealed as a key factor to be considered. ADMET property predictions revealed that apart from potential permeability issues, the synthesized N-acyl-N´-(β-D-glucopyranosyl) urea inhibitors have drug-like potential without any toxicity warnings.

Association between body weight and composition and plasma 25 hydroxyvitamin D level in the diabetes prevention program

USDA-ARS?s Scientific Manuscript database

Objective: We examined associations between body weight and plasma 25-hydroxyvitamin D concentration (25OHD) in prediabetes and sought to estimate the impact of adiposity on these associations. Methods: The study was conducted in the placebo (n = 1082) and intensive lifestyle (n = 1079) groups of ...

Two-Component Direct Fluorescent-Antibody Assay for Rapid Identification of Bacillus Anthracis

DTIC Science & Technology

2002-10-01

inhalational anthrax during the 2001 bioterrorism-associated anthrax out- break in the United States (6,17). Materials and Methods Bacterial Isolates B...n=6), pleural fluids (n=4), lung tissues (n=3), and lymph nodes (n=2), were collected from seven patients with laboratory-confirmed inhalational ...FITC) conjugates were lyophilized in HEPES buffer (0.05 M HEPES, pH 7.0, 0.10% glycine, 0.01 M d-sorbitol, 0.15 M KCl, and 5% d- trehalose ) containing

Titan's Ionic Species: Theoretical Treatment of N2H+ and Related Ions

NASA Astrophysics Data System (ADS)

Brites, V.; Hochlaf, M.

2009-06-01

We use different ab initio methods to compute the three-dimensional potential energy surface (3D-PES) of the ground state of N2H+. This includes the standard coupled cluster, the complete active space self-consistent field, the internally contacted multi reference configuration interaction, and the newly developed CCSD(T)-F12 methods. For the description of H and N atoms, several basis sets are tested. Then, we incorporate the 3D-PES analytical representations into variational calculations of the rovibrational spectrum of N2H+(X˜1Σ+) up to 7200 cm-1 above the zero point vibrational energy. Our data show that the CCSD(T)-F12/aug-cc-pVTZ approach represents a compromise for good description of the PES and computation cost. This technique is recommended for full dimensional PES generation of atmospheric and astrophysical relevant polyatomic systems. We applied this method to derive the rovibrational spectra of N2H+(X˜1Σ+) and of N2H++(X˜2Σ+). Finally, we discuss the existence of the N2H++(X˜2Σ+) in Titan's atmosphere.

A Variational Nodal Approach to 2D/1D Pin Resolved Neutron Transport for Pressurized Water Reactors

DOE PAGES

Zhang, Tengfei; Lewis, E. E.; Smith, M. A.; ...

2017-04-18

A two-dimensional/one-dimensional (2D/1D) variational nodal approach is presented for pressurized water reactor core calculations without fuel-moderator homogenization. A 2D/1D approximation to the within-group neutron transport equation is derived and converted to an even-parity form. The corresponding nodal functional is presented and discretized to obtain response matrix equations. Within the nodes, finite elements in the x-y plane and orthogonal functions in z are used to approximate the spatial flux distribution. On the radial interfaces, orthogonal polynomials are employed; on the axial interfaces, piecewise constants corresponding to the finite elements eliminate the interface homogenization that has been a challenge for method ofmore » characteristics (MOC)-based 2D/1D approximations. The angular discretization utilizes an even-parity integral method within the nodes, and low-order spherical harmonics (P N) on the axial interfaces. The x-y surfaces are treated with high-order P N combined with quasi-reflected interface conditions. Furthermore, the method is applied to the C5G7 benchmark problems and compared to Monte Carlo reference calculations.« less

A Variational Nodal Approach to 2D/1D Pin Resolved Neutron Transport for Pressurized Water Reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Tengfei; Lewis, E. E.; Smith, M. A.

A two-dimensional/one-dimensional (2D/1D) variational nodal approach is presented for pressurized water reactor core calculations without fuel-moderator homogenization. A 2D/1D approximation to the within-group neutron transport equation is derived and converted to an even-parity form. The corresponding nodal functional is presented and discretized to obtain response matrix equations. Within the nodes, finite elements in the x-y plane and orthogonal functions in z are used to approximate the spatial flux distribution. On the radial interfaces, orthogonal polynomials are employed; on the axial interfaces, piecewise constants corresponding to the finite elements eliminate the interface homogenization that has been a challenge for method ofmore » characteristics (MOC)-based 2D/1D approximations. The angular discretization utilizes an even-parity integral method within the nodes, and low-order spherical harmonics (P N) on the axial interfaces. The x-y surfaces are treated with high-order P N combined with quasi-reflected interface conditions. Furthermore, the method is applied to the C5G7 benchmark problems and compared to Monte Carlo reference calculations.« less

Sign changes in sums of the Liouville function

NASA Astrophysics Data System (ADS)

Borwein, Peter; Ferguson, Ron; Mossinghoff, Michael J.

2008-09-01

The Liouville function λ(n) is the completely multiplicative function whose value is -1 at each prime. We develop some algorithms for computing the sum T(n)Dsum_{kD1}^n λ(k)/k , and use these methods to determine the smallest positive integer n where T(n)<0 . This answers a question originating in some work of Turan, who linked the behavior of T(n) to questions about the Riemann zeta function. We also study the problem of evaluating Polya's sum L(n)Dsum_{kD1}^nλ(k) , and we determine some new local extrema for this function, including some new positive values.

Chemical structure determination of DNA bases modified by active metabolites of lucidin-3-O-primeveroside.

PubMed

Ishii, Yuji; Okamura, Toshiya; Inoue, Tomoki; Fukuhara, Kiyoshi; Umemura, Takashi; Nishikawa, Akiyoshi

2010-01-01

Lucidin-3-O- primeveroside (LuP) is one of the components of madder root (Rubia tinctorum L.; MR) which is reported to be carcinogenic in the kidney and liver of rats. Since metabolism of LuP generates genotoxic compounds such as lucidin (Luc) and rubiadin (Rub), it is likely that LuP plays a key role in MR carcinogenesis. In the present study, the chemical structures of Luc-specific 2'-deoxyguanosine (dG) and 2'-deoxyadenosine (dA) adducts following the reactions of dG and dA with a Luc carbocation or quinone methide intermediate derived from Acetoxy-Luc were determined by liquid chromatography with photodiode array and electron spray ionizaion-mass spectrometry (LC-PDA-ESI/MS). The identification of the two measurable adducts as Luc-N(2)-dG and Luc-N(6)-dA was confirmed by NMR analysis. Subsequently, using a newly developed quantitative analytical method using LC-ESI/MS, the formation of Luc-N(2)-dG and Luc-N(6)-dA from the reaction of calf thymus DNA with Luc in the presence of S9 mixture was observed. The fact that this reaction with Rub also gave rise to the same dG and dA adducts strongly suggests that Rub genotoxicity involves a metabolic conversion to Luc. The precise determination of the modified DNA bases generated by LuP and the method for their analysis may contribute to further comprehension of the mode of action underlying carcinogenesis by MR and related anthraquinones.

The Lagrange-Galerkin Method for the Two-dimensional Shallow Water Equations on Adaptive Grids

DTIC Science & Technology

2000-07-01

Dtu (xn+1/2) which requires the following extrapolation of the velocity field un+1/2...8u 86 Ç Ã Ã Ã É n+1 dVn+1= & Vn c Æ Ã Ã Ã È 8 8u 86 Ç Ã Ã Ã É n dVn + Dtu & Vn+1 c Æ Ã Ã Ã È 0 −8((8/(x)+ f86 −8((8/(y)− f8u Ç Ã Ã Ã É n+1 dVn+1 +Dt(1...momentum equations are & Vn+1 c(8u) dVn+1− Dtu & Vn+1 c( f86) dVn+1 = & Vn c(8u) dVn+Dt(1−u) & Vn c −8 (8 (x + f86 dVn+ Dtu & Vn+1 c −8 (8 (x

Validation of quantitative light-induced fluorescence-digital (QLF-D) for the detection of approximal caries in vitro.

PubMed

Ko, Hae-Youn; Kang, Si-Mook; Kim, Hee Eun; Kwon, Ho-Keun; Kim, Baek-Il

2015-05-01

Detection of approximal caries lesions can be difficult due to their anatomical position. This study aimed to assess the ability of the quantitative light-induced fluorescence-digital (QLF-D) in detecting approximal caries, and to compare the performance with those of the International Caries Detection and Assessment System II (ICDAS II) and digital radiography (DR). Extracted permanent teeth (n=100) were selected and mounted in pairs. The simulation pairs were assessed by one calibrated dentist using each detection method. After all the examinations, the teeth (n=95) were sectioned and examined histologically as gold standard. The modalities were compared in terms of sensitivity, specificity, areas under receiver operating characteristic curves (AUROC) for enamel (D1) and dentine (D3) levels. The intra-examiner reliability was assessed for all modalities. At D1 threshold, the ICDAS II presented the highest sensitivity (0.80) while the DR showed the highest specificity (0.89); however, the methods with the greatest AUC values at D1 threshold were DR and QLF-D (0.80 and 0.80 respectively). At D3 threshold, the methods with the highest sensitivity were ICDAS II and QLF-D (0.64 and 0.64 respectively) while the method with the lowest sensitivity was DR (0.50). However, with regard to the AUC values at D3 threshold, the QLF-D presented the highest value (0.76). All modalities showed to have excellent intra-examiner reliability. The newly developed QLF-D was not only able to detect proximal caries, but also showed to have comparable performance to the visual inspection and radiography in detecting proximal caries. QLF-D has the potential to be a useful detection method for proximal caries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Measurement of the lowest dosage of phenobarbital that can produce drug discrimination in rats

PubMed Central

Overton, Donald A.; Stanwood, Gregg D.; Patel, Bhavesh N.; Pragada, Sreenivasa R.; Gordon, M. Kathleen

2009-01-01

Rationale Accurate measurement of the threshold dosage of phenobarbital that can produce drug discrimination (DD) may improve our understanding of the mechanisms and properties of such discrimination. Objectives Compare three methods for determining the threshold dosage for phenobarbital (D) versus no drug (N) DD. Methods Rats learned a D versus N DD in 2-lever operant training chambers. A titration scheme was employed to increase or decrease dosage at the end of each 18-day block of sessions depending on whether the rat had achieved criterion accuracy during the sessions just completed. Three criterion rules were employed, all based on average percent drug lever responses during initial links of the last 6 D and 6 N sessions of a block. The criteria were: D%>66 and N%<33; D%>50 and N%<50; (D%-N%)>33. Two squads of rats were trained, one immediately after the other. Results All rats discriminated drug versus no drug. In most rats, dosage decreased to low levels and then oscillated near the minimum level required to maintain criterion performance. The lowest discriminated dosage significantly differed under the three criterion rules. The squad that was trained 2nd may have benefited by partially duplicating the lever choices of the previous squad. Conclusions The lowest discriminated dosage is influenced by the criterion of discriminative control that is employed, and is higher than the absolute threshold at which discrimination entirely disappears. Threshold estimations closer to absolute threshold can be obtained when criteria are employed that are permissive, and that allow rats to maintain lever preferences. PMID:19082992

Optimized efficiency in InP nanowire solar cells with accurate 1D analysis

NASA Astrophysics Data System (ADS)

Chen, Yang; Kivisaari, Pyry; Pistol, Mats-Erik; Anttu, Nicklas

2018-01-01

Semiconductor nanowire arrays are a promising candidate for next generation solar cells due to enhanced absorption and reduced material consumption. However, to optimize their performance, time consuming three-dimensional (3D) opto-electronics modeling is usually performed. Here, we develop an accurate one-dimensional (1D) modeling method for the analysis. The 1D modeling is about 400 times faster than 3D modeling and allows direct application of concepts from planar pn-junctions on the analysis of nanowire solar cells. We show that the superposition principle can break down in InP nanowires due to strong surface recombination in the depletion region, giving rise to an IV-behavior similar to that with low shunt resistance. Importantly, we find that the open-circuit voltage of nanowire solar cells is typically limited by contact leakage. Therefore, to increase the efficiency, we have investigated the effect of high-bandgap GaP carrier-selective contact segments at the top and bottom of the InP nanowire and we find that GaP contact segments improve the solar cell efficiency. Next, we discuss the merit of p-i-n and p-n junction concepts in nanowire solar cells. With GaP carrier selective top and bottom contact segments in the InP nanowire array, we find that a p-n junction design is superior to a p-i-n junction design. We predict a best efficiency of 25% for a surface recombination velocity of 4500 cm s-1, corresponding to a non-radiative lifetime of 1 ns in p-n junction cells. The developed 1D model can be used for general modeling of axial p-n and p-i-n junctions in semiconductor nanowires. This includes also LED applications and we expect faster progress in device modeling using our method.

Optimized efficiency in InP nanowire solar cells with accurate 1D analysis.

PubMed

Chen, Yang; Kivisaari, Pyry; Pistol, Mats-Erik; Anttu, Nicklas

2018-01-26

Semiconductor nanowire arrays are a promising candidate for next generation solar cells due to enhanced absorption and reduced material consumption. However, to optimize their performance, time consuming three-dimensional (3D) opto-electronics modeling is usually performed. Here, we develop an accurate one-dimensional (1D) modeling method for the analysis. The 1D modeling is about 400 times faster than 3D modeling and allows direct application of concepts from planar pn-junctions on the analysis of nanowire solar cells. We show that the superposition principle can break down in InP nanowires due to strong surface recombination in the depletion region, giving rise to an IV-behavior similar to that with low shunt resistance. Importantly, we find that the open-circuit voltage of nanowire solar cells is typically limited by contact leakage. Therefore, to increase the efficiency, we have investigated the effect of high-bandgap GaP carrier-selective contact segments at the top and bottom of the InP nanowire and we find that GaP contact segments improve the solar cell efficiency. Next, we discuss the merit of p-i-n and p-n junction concepts in nanowire solar cells. With GaP carrier selective top and bottom contact segments in the InP nanowire array, we find that a p-n junction design is superior to a p-i-n junction design. We predict a best efficiency of 25% for a surface recombination velocity of 4500 cm s -1 , corresponding to a non-radiative lifetime of 1 ns in p-n junction cells. The developed 1D model can be used for general modeling of axial p-n and p-i-n junctions in semiconductor nanowires. This includes also LED applications and we expect faster progress in device modeling using our method.

Direct high-performance liquid chromatographic determination of the enantiomeric purity of levodopa and methyldopa: comparison with pharmacopoeial polarimetric methods.

PubMed

Dolezalová, M; Tkaczyková, M

1999-03-01

Chiral high-performance liquid chromatography was employed for determination of the enantiomeric purity of levodopa and methyldopa. The determination of D-DOPA in levodopa was accomplished using a chiral ligand-exchange chromatograpy with an ordinary C18 column and a chiral mobile phase containing N,N-dimethyl-L-phenylalanine and Cu(II) acetate or by means of LC on a teicoplanin column in conjunction with ethanol-water (65:35, v/v). Both methods gave good performance, however, the latter was faster and more convenient and suitable for routine analyses. For the determination of D-methyldopa a LC method based on the use of a teicoplanin column in polar organic mode with methanol-acetic acid-triethylamine (1,000:0.05:0.05, v/v/v) mobile phase was developed. The precision, accuracy, linearity and selectivity were satisfactory. In comparison with pharmacopoeial polarimetric methods (according to the European Pharmacopoeia and the Pharmacopoea Bohemoslovaca), the LC methods proved to be much more sensitive giving detection limits 0.04% of D-DOPA and 0.3% of D-methyldopa.

Multidimensional radiative transfer with multilevel atoms. II. The non-linear multigrid method.

NASA Astrophysics Data System (ADS)

Fabiani Bendicho, P.; Trujillo Bueno, J.; Auer, L.

1997-08-01

A new iterative method for solving non-LTE multilevel radiative transfer (RT) problems in 1D, 2D or 3D geometries is presented. The scheme obtains the self-consistent solution of the kinetic and RT equations at the cost of only a few (<10) formal solutions of the RT equation. It combines, for the first time, non-linear multigrid iteration (Brandt, 1977, Math. Comp. 31, 333; Hackbush, 1985, Multi-Grid Methods and Applications, springer-Verlag, Berlin), an efficient multilevel RT scheme based on Gauss-Seidel iterations (cf. Trujillo Bueno & Fabiani Bendicho, 1995ApJ...455..646T), and accurate short-characteristics formal solution techniques. By combining a valid stopping criterion with a nested-grid strategy a converged solution with the desired true error is automatically guaranteed. Contrary to the current operator splitting methods the very high convergence speed of the new RT method does not deteriorate when the grid spatial resolution is increased. With this non-linear multigrid method non-LTE problems discretized on N grid points are solved in O(N) operations. The nested multigrid RT method presented here is, thus, particularly attractive in complicated multilevel transfer problems where small grid-sizes are required. The properties of the method are analyzed both analytically and with illustrative multilevel calculations for Ca II in 1D and 2D schematic model atmospheres.

Distribution, industrial applications, and enzymatic synthesis of D-amino acids.

PubMed

Gao, Xiuzhen; Ma, Qinyuan; Zhu, Hailiang

2015-04-01

D-Amino acids exist widely in microbes, plants, animals, and food and can be applied in pharmaceutical, food, and cosmetics. Because of their widespread applications in industry, D-amino acids have recently received more and more attention. Enzymes including D-hydantoinase, N-acyl-D-amino acid amidohydrolase, D-amino acid amidase, D-aminopeptidase, D-peptidase, L-amino acid oxidase, D-amino acid aminotransferase, and D-amino acid dehydrogenase can be used for D-amino acids synthesis by kinetic resolution or asymmetric amination. In this review, the distribution, industrial applications, and enzymatic synthesis methods are summarized. And, among all the current enzymatic methods, D-amino acid dehydrogenase method not only produces D-amino acid by a one-step reaction but also takes environment and atom economics into consideration; therefore, it is deserved to be paid more attention.

Measurement of free glucocorticoids: quantifying corticosteroid-binding globulin binding affinity and its variation within and among mammalian species.

PubMed

Delehanty, Brendan; Hossain, Sabrina; Jen, Chao Ching; Crawshaw, Graham J; Boonstra, Rudy

2015-01-01

Plasma glucocorticoids (GCs) are commonly used as measures of stress in wildlife. A great deal of evidence indicates that only free GC (GC not bound by the specific binding protein, corticosteroid-binding globulin, CBG) leaves the circulation and exerts biological effects on GC-sensitive tissues. Free hormone concentrations are difficult to measure directly, so researchers estimate free GC using two measures: the binding affinity and the binding capacity in plasma. We provide an inexpensive saturation binding method for calculating the binding affinity (equilibrium dissociation constant, K d) of CBG that can be run without specialized laboratory equipment. Given that other plasma proteins, such as albumin, also bind GCs, the method compensates for this non-specific binding. Separation of bound GC from free GC was achieved with dextran-coated charcoal. The method provides repeatable estimates (12% coefficient of variation in the red squirrel, Tamiasciurus hudsonicus), and there is little evidence of inter-individual variation in K d (range 2.0-7.3 nM for 16 Richardson's ground squirrels, Urocitellus richardsonii). The K d values of 28 mammalian species we assessed were mostly clustered around a median of 4 nM, but five species had values between 13 and 61 nM. This pattern may be distinct from birds, for which published values are more tightly distributed (1.5-5.1 nM). The charcoal separation method provides a reliable and robust method for measuring the K d in a wide range of species. It uses basic laboratory equipment to provide rapid results at very low cost. Given the importance of CBG in regulating the biological activity of GCs, this method is a useful tool for physiological ecologists.

The growth and investigations of electromechanical properties of Fresnoite Ba2Si2TiO8 crystal as a function of orientation

NASA Astrophysics Data System (ADS)

Shen, Chuanying; Wang, Duanliang; Zhang, Jinyue; Zhang, Huaijin; Wang, Jiyang; Boughton, Robert I.

2018-04-01

Large sized Fresnoite Ba2TiSi2O8 single crystals were grown by the Czochralski method. Using coordinate transformation methods, the relative dielectric, piezoelectric and elastic constants of Fresnoite Ba2TiSi2O8 as a function of orientation were investigated, and their two- and three-dimensional spatial distributions are presented. From them, the maximum values of the piezoelectric coefficients and the corresponding rotation angle can be obtained. The maximum values of coefficients d22∗, d23∗, d24∗, d32∗, d33∗ and d34∗ were achieved for rotation angles of 40°, 32°, 0°, 58°, 50° and 90°, respectively, and are on the order of 8.7, -4.7, 17.5, 4.7, 8.7 and 17.5 pC/N, respectively. Furthermore, the validity of the electromechanical properties investigation as a function of orientation was verified. The relative dielectric permittivity, elastic constant and piezoelectric coefficient of a ZXl50o cut rod were calculated and found to be 14.1, 8.7 pC/N and 11.2 pm2/N, respectively, in good agreement with the experimental values of 12.7, 9.1 pC/N and 11.7 pm2/N. This investigation is important in providing direction for theoretical research and device design of piezoelectric Ba2TiSi2O8 crystals.

Subcritical crack growth in porcelains, glass-ceramics, and glass-infiltrated alumina composite for dental restorations.

PubMed

Gonzaga, Carla Castiglia; Yoshimura, Humberto Naoyuki; Cesar, Paulo Francisco; Miranda, Walter Gomes

2009-05-01

The objective was to compare fracture toughness (K(Ic)), stress corrosion susceptibility coefficient (n), and stress intensity factor threshold for crack propagation (K(I0)) of two porcelains [VM7/Vita (V) and d.Sign/Ivoclar (D)], two glass-ceramics [Empress/Ivolcar (E1) and Empress2/Ivlocar (E2)] and a glass-infiltrated alumina composite [In-Ceram Alumina/Vita (IC)]. Disks were constructed according to each manufacturer's processing method, and polished before induction of cracks by a Vickers indenter. Crack lengths were measured under optical microscopy at times between 0.1 and 100 h. Specimens were stored in artificial saliva at 37 degrees C during the whole experiment. K(Ic) and n were determined using indentation fracture method. K(I0) was determined by plotting log crack velocity versus log K(I). Microstructure characterization was carried out under SEM, EDS, X-ray diffraction and X-ray fluorescence. IC and E2 presented higher K(Ic) and K(I0) compared to E1, V, and D. IC presented the highest n value, followed by E2, D, E1, and V in a decreasing order. V and D presented similar K(Ic), but porcelain V showed higher K(I0) and lower n compared to D. Microstructure features (volume fraction, size, aspect ratio of crystalline phases and chemical composition of glassy matrix) determined K(Ic). The increase of K(Ic) value favored the increases of n and K(I0).

Occupancy mapping and surface reconstruction using local Gaussian processes with Kinect sensors.

PubMed

Kim, Soohwan; Kim, Jonghyuk

2013-10-01

Although RGB-D sensors have been successfully applied to visual SLAM and surface reconstruction, most of the applications aim at visualization. In this paper, we propose a noble method of building continuous occupancy maps and reconstructing surfaces in a single framework for both navigation and visualization. Particularly, we apply a Bayesian nonparametric approach, Gaussian process classification, to occupancy mapping. However, it suffers from high-computational complexity of O(n(3))+O(n(2)m), where n and m are the numbers of training and test data, respectively, limiting its use for large-scale mapping with huge training data, which is common with high-resolution RGB-D sensors. Therefore, we partition both training and test data with a coarse-to-fine clustering method and apply Gaussian processes to each local clusters. In addition, we consider Gaussian processes as implicit functions, and thus extract iso-surfaces from the scalar fields, continuous occupancy maps, using marching cubes. By doing that, we are able to build two types of map representations within a single framework of Gaussian processes. Experimental results with 2-D simulated data show that the accuracy of our approximated method is comparable to previous work, while the computational time is dramatically reduced. We also demonstrate our method with 3-D real data to show its feasibility in large-scale environments.

2D dark-count-rate modeling of PureB single-photon avalanche diodes in a TCAD environment

NASA Astrophysics Data System (ADS)

Knežević, Tihomir; Nanver, Lis K.; Suligoj, Tomislav

2018-02-01

PureB silicon photodiodes have nm-shallow p+n junctions with which photons/electrons with penetration-depths of a few nanometer can be detected. PureB Single-Photon Avalanche Diodes (SPADs) were fabricated and analysed by 2D numerical modeling as an extension to TCAD software. The very shallow p+ -anode has high perimeter curvature that enhances the electric field. In SPADs, noise is quantified by the dark count rate (DCR) that is a measure for the number of false counts triggered by unwanted processes in the non-illuminated device. Just like for desired events, the probability a dark count increases with increasing electric field and the perimeter conditions are critical. In this work, the DCR was studied by two 2D methods of analysis: the "quasi-2D" (Q-2D) method where vertical 1D cross-sections were assumed for calculating the electron/hole avalanche-probabilities, and the "ionization-integral 2D" (II-2D) method where crosssections were placed where the maximum ionization-integrals were calculated. The Q-2D method gave satisfactory results in structures where the peripheral regions had a small contribution to the DCR, such as in devices with conventional deepjunction guard rings (GRs). Otherwise, the II-2D method proved to be much more precise. The results show that the DCR simulation methods are useful for optimizing the compromise between fill-factor and p-/n-doping profile design in SPAD devices. For the experimentally investigated PureB SPADs, excellent agreement of the measured and simulated DCR was achieved. This shows that although an implicit GR is attractively compact, the very shallow pn-junction gives a risk of having such a low breakdown voltage at the perimeter that the DCR of the device may be negatively impacted.

[Detection of auditory impairment in the offsprings caused by drug treatment of the dams].

PubMed

Kameyama, T; Nabeshima, T; Itoh, J

1982-12-01

To study the auditory impairment induced by prenatal administration of aminoglycosides in the offspring, the shuttle box method to measure the auditory threshold of rats (Kameyama et al., Folia pharmacol. japon. 77, 15, 1981) was employed. Four groups of pregnant rats were administered 200 mg/kg kanamycin sulfate (KM), 200 mg/kg dihydrostreptomycin sulfate (DHSM), 100 mg/kg neomycin sulfate (NM), or 1 ml/kg saline intramuscularly from the 10th to the 19th day of pregnancy. The auditory threshold of the offspring could be measured by the shuttle box method in about 90% of the live born rats at the age of 100 days. The auditory thresholds of the groups were as follows (mean +/- S.E.): saline group, 53.8 +/- 0.6 dB (N = 36); KM group, 63.8 +/- 1.1 dB (N = 34); DHSM group, 60.0 +/- 1.2 dB (N = 29); NM group, 62.4 +/- 1.2 dB (N = 24). Auditory thresholds of drug-treated groups were significantly higher than that of the saline group. However, no increase in the auditory threshold of the mother rat was detected after treatment with aminoglycosides. In addition, the experimental procedure of the shuttle box method is very easy, and the auditory threshold of a large number of rats could be measured in a short period. These findings suggest that this method is a very useful one for screening for auditory impairment induced by prenatal drug treatment in rat offspring.

IMAGING BRAIN SIGNAL TRANSDUCTION AND METABOLISM VIA ARACHIDONIC AND DOCOSAHEXAENOIC ACID IN ANIMALS AND HUMANS

PubMed Central

Basselin, Mireille; Ramadan, Epolia; Rapoport, Stanley I.

2012-01-01

The polyunsaturated fatty acids (PUFAs), arachidonic acid (AA, 20:4n-6) and docosahexaenoic acid (DHA, 22:6n-3), important second messengers in brain, are released from membrane phospholipid following receptor-mediated activation of specific phospholipase A2 (PLA2) enzymes. We developed an in vivo method in rodents using quantitative autoradiography to image PUFA incorporation into brain from plasma, and showed that their incorporation rates equal their rates of metabolic consumption by brain. Thus, quantitative imaging of unesterified plasma AA or DHA incorporation into brain can be used as a biomarker of brain PUFA metabolism and neurotransmission. We have employed our method to image and quantify effects of mood stabilizers on brain AA/DHA incorporation during neurotransmission by muscarinic M1,3,5, serotonergic 5-HT2A/2C, dopaminergic D2-like (D2, D3, D4) or glutamatergic N-methyl-D-aspartic acid (NMDA) receptors, and effects of inhibition of acetylcholinesterase, of selective serotonin and dopamine reuptake transporter inhibitors, of neuroinflammation (HIV-1 and lipopolysaccharide) and excitotoxicity, and in genetically modified rodents. The method has been extended for the use with positron emission tomography (PET), and can be employed to determine how human brain AA/DHA signaling and consumption are influenced by diet, aging, disease and genetics. PMID:22178644

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chenna, Ahmed; Gupta, Ramesh C.; Bonala, Radha R.

N2-(4-Hydroxyphenyl)-2'-deoxyguanosine-5'-O-DMT-3'-phosphoramidite has been synthesized and used to incorporate the N2-(4-hydroxyphenyl)-2'-dG (N2-4-HOPh-dG) into DNA, using solid-state synthesis technology. The key step to obtaining the xenonucleoside is a palladium (Xantphos-chelated) catalyzed N2-arylation (Buchwald-Hartwig reaction) of a fully protected 2'-deoxyguanosine derivative by 4-isobutyryloxybromobenzene. The reaction proceeded in good yield and the adduct was converted to the required 5'-O-DMT-3'-O-phosphoramidite by standard methods. The latter was used to synthesize oligodeoxynucleotides in which the N2-4-HOPh-dG adduct was incorporated site-specifically. The oligomers were purified by reverse-phase HPLC. Enzymatic hydrolysis and HPLC analysis confirmed the presence of this adduct in the oligomers.

Depth extraction method with high accuracy in integral imaging based on moving array lenslet technique

NASA Astrophysics Data System (ADS)

Wang, Yao-yao; Zhang, Juan; Zhao, Xue-wei; Song, Li-pei; Zhang, Bo; Zhao, Xing

2018-03-01

In order to improve depth extraction accuracy, a method using moving array lenslet technique (MALT) in pickup stage is proposed, which can decrease the depth interval caused by pixelation. In this method, the lenslet array is moved along the horizontal and vertical directions simultaneously for N times in a pitch to get N sets of elemental images. Computational integral imaging reconstruction method for MALT is taken to obtain the slice images of the 3D scene, and the sum modulus (SMD) blur metric is taken on these slice images to achieve the depth information of the 3D scene. Simulation and optical experiments are carried out to verify the feasibility of this method.

Simultaneous acquisition of 2D and 3D solid-state NMR experiments for sequential assignment of oriented membrane protein samples.

PubMed

Gopinath, T; Mote, Kaustubh R; Veglia, Gianluigi

2015-05-01

We present a new method called DAISY (Dual Acquisition orIented ssNMR spectroScopY) for the simultaneous acquisition of 2D and 3D oriented solid-state NMR experiments for membrane proteins reconstituted in mechanically or magnetically aligned lipid bilayers. DAISY utilizes dual acquisition of sine and cosine dipolar or chemical shift coherences and long living (15)N longitudinal polarization to obtain two multi-dimensional spectra, simultaneously. In these new experiments, the first acquisition gives the polarization inversion spin exchange at the magic angle (PISEMA) or heteronuclear correlation (HETCOR) spectra, the second acquisition gives PISEMA-mixing or HETCOR-mixing spectra, where the mixing element enables inter-residue correlations through (15)N-(15)N homonuclear polarization transfer. The analysis of the two 2D spectra (first and second acquisitions) enables one to distinguish (15)N-(15)N inter-residue correlations for sequential assignment of membrane proteins. DAISY can be implemented in 3D experiments that include the polarization inversion spin exchange at magic angle via I spin coherence (PISEMAI) sequence, as we show for the simultaneous acquisition of 3D PISEMAI-HETCOR and 3D PISEMAI-HETCOR-mixing experiments.

Etude des trois molecules H 2P-NH 2, ClHP-NH 2, H 2P-NHCl au moyen d'une methode de pseudopotentiels

NASA Astrophysics Data System (ADS)

Barthelat, M.; Mathis, R.; Mathis, F.

The three molecules H 2P-NH 2, ClHP-NH 2 and H 2P-NHCl have been studied by a pseudo-potential method, with a minimal basis of quality mono-zeta, with 3 d functions on the phosphorus atom. The geometry of each molecule was optimized and the phosphorus-nitrogen rotation barrier calculated. The results of the calculations confirm that the polarity of the phosphorus-nitrogen bond is P +-N -. Three weak interactions appear: a partial coordinative bond between the nitrogen doublet and a 3 d orbital of the phosphorus atom, hyperconjugation between the nitrogen doublet and the P-H bonds, and participation of the 3 d orbital of phosphorus in the P-N bond.

Comparison of various NMR methods for the indirect detection of nitrogen-14 nuclei via protons in solids

NASA Astrophysics Data System (ADS)

Shen, Ming; Trébosc, Julien; O'Dell, Luke A.; Lafon, Olivier; Pourpoint, Frédérique; Hu, Bingwen; Chen, Qun; Amoureux, Jean-Paul

2015-09-01

We present an experimental comparison of several through-space Hetero-nuclear Multiple-Quantum Correlation experiments, which allow the indirect observation of homo-nuclear single- (SQ) or double-quantum (DQ) 14N coherences via spy 1H nuclei. These 1H-{14N} D-HMQC sequences differ not only by the order of 14N coherences evolving during the indirect evolution, t1, but also by the radio-frequency (rf) scheme used to excite and reconvert these coherences under Magic-Angle Spinning (MAS). Here, the SQ coherences are created by the application of center-band frequency-selective pulses, i.e. long and low-power rectangular pulses at the 14N Larmor frequency, ν0(14N), whereas the DQ coherences are excited and reconverted using rf irradiation either at ν0(14N) or at the 14N overtone frequency, 2ν0(14N). The overtone excitation is achieved either by constant frequency rectangular pulses or by frequency-swept pulses, specifically Wide-band, Uniform-Rate, and Smooth-Truncation (WURST) pulse shapes. The present article compares the performances of four different 1H-{14N} D-HMQC sequences, including those with 14N rectangular pulses at ν0(14N) for the indirect detection of homo-nuclear (i) 14N SQ or (ii) DQ coherences, as well as their overtone variants using (iii) rectangular or (iv) WURST pulses. The compared properties include: (i) the sensitivity, (ii) the spectral resolution in the 14N dimension, (iii) the rf requirements (power and pulse length), as well as the robustness to (iv) rf offset and (v) MAS frequency instabilities. Such experimental comparisons are carried out for γ-glycine and L-histidine.HCl monohydrate, which contain 14N sites subject to moderate quadrupole interactions. We demonstrate that the optimum choice of the 1H-{14N} D-HMQC method depends on the experimental goal. When the sensitivity and/or the robustness to offset are the major concerns, the D-HMQC sequence allowing the indirect detection of 14N SQ coherences should be employed. Conversely, when the highest resolution and/or adjusted indirect spectral width are needed, overtone experiments are the method of choice. The overtone scheme using WURST pulses results in broader excitation bandwidths than that using rectangular pulses, at the expense of reduced sensitivity. Numerically exact simulations also show that the sensitivity of the overtone 1H-{14N} D-HMQC experiment increases for larger quadrupole interactions.

Estimating diversifying selection and functional constraint in the presence of recombination.

PubMed

Wilson, Daniel J; McVean, Gilean

2006-03-01

Models of molecular evolution that incorporate the ratio of nonsynonymous to synonymous polymorphism (dN/dS ratio) as a parameter can be used to identify sites that are under diversifying selection or functional constraint in a sample of gene sequences. However, when there has been recombination in the evolutionary history of the sequences, reconstructing a single phylogenetic tree is not appropriate, and inference based on a single tree can give misleading results. In the presence of high levels of recombination, the identification of sites experiencing diversifying selection can suffer from a false-positive rate as high as 90%. We present a model that uses a population genetics approximation to the coalescent with recombination and use reversible-jump MCMC to perform Bayesian inference on both the dN/dS ratio and the recombination rate, allowing each to vary along the sequence. We demonstrate that the method has the power to detect variation in the dN/dS ratio and the recombination rate and does not suffer from a high false-positive rate. We use the method to analyze the porB gene of Neisseria meningitidis and verify the inferences using prior sensitivity analysis and model criticism techniques.

Estimating Diversifying Selection and Functional Constraint in the Presence of Recombination

PubMed Central

Wilson, Daniel J.; McVean, Gilean

2006-01-01

Models of molecular evolution that incorporate the ratio of nonsynonymous to synonymous polymorphism (dN/dS ratio) as a parameter can be used to identify sites that are under diversifying selection or functional constraint in a sample of gene sequences. However, when there has been recombination in the evolutionary history of the sequences, reconstructing a single phylogenetic tree is not appropriate, and inference based on a single tree can give misleading results. In the presence of high levels of recombination, the identification of sites experiencing diversifying selection can suffer from a false-positive rate as high as 90%. We present a model that uses a population genetics approximation to the coalescent with recombination and use reversible-jump MCMC to perform Bayesian inference on both the dN/dS ratio and the recombination rate, allowing each to vary along the sequence. We demonstrate that the method has the power to detect variation in the dN/dS ratio and the recombination rate and does not suffer from a high false-positive rate. We use the method to analyze the porB gene of Neisseria meningitidis and verify the inferences using prior sensitivity analysis and model criticism techniques. PMID:16387887

Selective Functionalization of Carbon Nanotubes: Part II

NASA Technical Reports Server (NTRS)

Meyyappan, Meyya; Khare, Bishun

2010-01-01

An alternative method of low-temperature plasma functionalization of carbon nanotubes provides for the simultaneous attachment of molecular groups of multiple (typically two or three) different species or different mixtures of species to carbon nanotubes at different locations within the same apparatus. This method is based on similar principles, and involves the use of mostly the same basic apparatus, as those of the methods described in "Low-Temperature Plasma Functionalization of Carbon Nanotubes" (ARC-14661-1), NASA Tech Briefs, Vol. 28, No. 5 (May 2004), page 45. The figure schematically depicts the basic apparatus used in the aforementioned method, with emphasis on features that distinguish the present alternative method from the other. In this method, one exploits the fact that the composition of the deposition plasma changes as the plasma flows from its source in the precursor chamber toward the nanotubes in the target chamber. As a result, carbon nanotubes mounted in the target chamber at different flow distances (d1, d2, d3 . . .) from the precursor chamber become functionalized with different species or different mixtures of species. In one series of experiments to demonstrate this method, N2 was used as the precursor gas. After the functionalization process, the carbon nanotubes from three different positions in the target chamber were examined by Fourier-transform infrared spectroscopy to identify the molecular groups that had become attached. On carbon nanotubes from d1 = 1 cm, the attached molecular groups were found to be predominantly C-N and C=N. On carbon nanotubes from d2 = 2.5 cm, the attached molecular groups were found to be predominantly C-(NH)2 and/or C=NH2. (The H2 was believed to originate as residual hydrogen present in the nanotubes.) On carbon nanotubes from d3 = 7 cm no functionalization could be detected - perhaps, it was conjectured, because this distance is downstream of the plasma source, all of the free ions and free radicals of the plasma had recombined into molecules.

Enhancements to the Bayesian Infrasound Source Location Method

DTIC Science & Technology

2012-09-01

ENHANCEMENTS TO THE BAYESIAN INFRASOUND SOURCE LOCATION METHOD Omar E. Marcillo, Stephen J. Arrowsmith, Rod W. Whitaker, and Dale N. Anderson Los...ABSTRACT We report on R&D that is enabling enhancements to the Bayesian Infrasound Source Location (BISL) method for infrasound event location...the Bayesian Infrasound Source Location Method 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

Datasets of Odontocete Sounds Annotated for Developing Automatic Detection Methods, FY09-10

DTIC Science & Technology

2012-09-01

San Diego State University) for the classification dataset and Eva-Marie Nosal (University of Hawaii) and Steve Martin (SPAWAR) for the localization...Conference papers (non-refereed) MARQUES, T. A., S. W. MARTIN, R. P. MORRISSEY, S. JARVIS , N. DIMARZIO, D. MORETTI, AND D. K. MELLINGER...clicks. J. Acoust. Soc. Am. 129(4): 2536(A). MARQUES, T. A., L. THOMAS, S. W. MARTIN, D. K. MELLINGER, S. JARVIS , N. DIMARZIO, AND R. P

Variation in clinical vitamin D status by DiaSorin Liaison and LC-MS/MS in the presence of elevated 25-OH vitamin D2.

PubMed

de Koning, Lawrence; Al-Turkmani, M Rabie; Berg, Anders H; Shkreta, Aida; Law, Terence; Kellogg, Mark D

2013-01-16

We compared total 25-OH vitamin D status measured by DiaSorin Liaison and tandem mass spectrometry (LC-MS/MS) among patients with high and low 25-OH vitamin D(2). Total 25-OH vitamin D was measured in plasma containing high (>25 nmol/l or >50%, n=26) and low (<2.5 nmol/l, n=29) 25-OH vitamin D(2) using DiaSorin Liaison and an LC-MS/MS method using NIST 972-verified calibrators. Samples were classified as vitamin D adequate (total 25-OH vitamin D ≥50 nmol/l), and inadequate or deficient (<50 nmol/l) by each method. Deming and multiple linear regression were used to compare methods. Samples were significantly more likely to be classified as inadequate or deficient by DiaSorin Liaison (36%) vs LC-MS/MS (9%). This increased in the presence of high 25-OH vitamin D2 (42% vs 0%). Total 25-OH vitamin D by DiaSorin Liaison was 26.0 nmol/l lower than LC-MS/MS, which increased to 34.1 nmol/l among samples with high 25-OH vitamin D(2). This was attributed to lower recovery of 25-OH vitamin D(2) (proportional bias=0.64 nmol/l) by DiaSorin Liaison, independent of D(3) (proportional bias=0.86 nmol/l). Patients were more likely to be classified as vitamin D inadequate or deficient by DiaSorin Liaison compared to an LC-MS/MS method, which was in part due to the presence of 25-OH vitamin D(2). Copyright © 2012 Elsevier B.V. All rights reserved.

The Electronic Structure of the Cs/ n-GaN(0001) Nano-Interface

NASA Astrophysics Data System (ADS)

Benemanskaya, G. V.; Lapushkin, M. N.; Marchenko, D. E.; Timoshnev, S. N.

2018-03-01

Electronic structures of the n-GaN(0001) surface and Cs/ n-GaN(0001) interface with submonolayer Cs coverages were studied for the first time in situ by the photoelectron spectroscopy (PES) method. The spectra of photoemission from the valence band, surface electron states, and core levels (Ga 3 d, Cs 4 d, Cs 5 p) under synchrotron excitation were measured in a range of photon energies within 50-150 eV. Evolution of the spectrum of surface states near the valence-band maximum was revealed by PES during the adsorption of Cs atoms. A metallic character of the Cs/ n-GaN(0001) nano-interface is demonstrated.

Shipyard Marking Methods

DTIC Science & Technology

1980-09-01

K ( 7 ) D , SOAPSTONE ( 1 3 ) E. lNK (5) F. CRAYON OR PAINT STICK (14) G.DYE (1) H . PE N C I L ( 1 ) 1. ELECTRIC ENGRAVING (1) 2. WHO MANUFACTURES...CHALK ( 2 ) D . DYE (1) H, SOAPSTONE (4) 4. W HAT TYPE OF DISPENSING METHOD IS UTILIZED WITH MARKING MATERIALS? A . BALL POINT TUBE ( 1 3 ) H , STEEL...9 ) L, BAMBOO PEN & INK POT F. SOAPSTONE (12) M . OIL PENCIL ( 1 ) G . L A C S T I C K ( 0 ) N . ELECTRI c ENGRAVER (1) 5, ARE STANDARD COLORS

L'effet Hall Quantique

NASA Astrophysics Data System (ADS)

Samson, Thomas

Nous proposons une methode permettant d'obtenir une expression pour la conductivite de Hall de structures electroniques bidimensionnelles et nous examinons celle -ci a la limite d'une temperature nulle dans le but de verifier l'effet Hall quantique. Nous allons nous interesser essentiellement a l'effet Hall quantique entier et aux effets fractionnaires inferieurs a un. Le systeme considere est forme d'un gaz d'electrons en interaction faible avec les impuretes de l'echantillon. Le modele du gaz d'electrons consiste en un gaz bidimensionnel d'electrons sans spin expose perpendiculairement a un champ magnetique uniforme. Ce dernier est decrit par le potentiel vecteur vec{rm A} defini dans la jauge de Dingle ou jauge symetrique. Conformement au formalisme de la seconde quantification, l'hamiltonien de ce gaz est represente dans la base des etats a un-corps de Dingle |n,m> et exprime ainsi en terme des operateurs de creation et d'annihilation correspondants a_sp{ rm n m}{dag} et a _{rm n m}. Nous supposons de plus que les electrons du niveau fondamental de Dingle interagissent entre eux via le potentiel coulombien. La methode utilisee fait appel a une equation mai tresse a N-corps, de nature quantique et statistique, et verifiant le second principe de la thermodynamique. A partir de celle-ci, nous obtenons un systeme d'equations differentielles appele hierarchie d'equations quantique dont la resolution nous permet de determiner une equation a un-corps, dite de Boltzmann quantique, et dictant l'evolution de la moyenne statistique de l'operateur non-diagonal a _sp{rm n m}{dag } a_{rm n}, _{rm m}, sous l'action du champ electrique applique vec{rm E}(t). C'est sa solution Tr(p(t) a _sp{rm n m}{dag} a_{rm n},_ {rm m}), qui definit la relation de convolution entre la densite courant de Hall vec{rm J}_{rm H }(t) et le champ electrique vec {rm E}(t) dont la transformee de Laplace-Fourier du noyau nous fournit l'expression de la conductivite de Hall desiree. Pour une valeur de facteur d'occupation (nombre d'electrons/degenerescence des etats de Dingle) superieure a un, c'est-a-dire en absence d'interaction electron-electron, il nous sera facile d'evaluer cette conductivite a la limite d'une temperature nulle et de demontrer qu'elle tend vers l'une des valeurs quantiques qe^2/h conformement a l'effet Hall quantique entier. Cependant, pour une valeur du facteur d'occupation inferieure a un, c'est-a-dire en presence d'interaction electron-electron, nous ne pourrons evaluer cette limite et obtenir les resultats escomptes a cause de l'impossibilite de determiner l'un des termes impliques. Neanmoins, ce dernier etant de nature statistique, il pourra etre aisement mis en fonction du propagateur du gaz d'electrons dont on doit maintenant determiner une expression en regime effet Hall quantique fractionnaire. Apres avoir demontre l'impuissance de la theorie des perturbations, basee sur le theoreme de Wick et la technique des diagrammes de Feynman, a accomplir cette tache correctement, nous proposons une seconde methode. Celle -ci fait appel au formalisme de l'integrale fonctionnelle et a l'utilisation d'une transformation de Hubbard-Stratonovich generalisee permettant de substituer a l'interaction a deux-corps une interaction effective a un-corps. L'expression finale obtenue bien que non completement resolue, devrait pouvoir etre estimee par une bonne approximation analytique ou au pire numeriquement.

Fabrication of single phase 2D homologous perovskite microplates by mechanical exfoliation

NASA Astrophysics Data System (ADS)

Li, Junze; Wang, Jun; Zhang, Yingjun; Wang, Haizhen; Lin, Gaoming; Xiong, Xuan; Zhou, Weihang; Luo, Hongmei; Li, Dehui

2018-04-01

The two-dimensional (2D) Ruddlesden-Popper type perovskites have attracted intensive interest for their great environmental stability and various potential optoelectronic applications. Fundamental understanding of the photophysical and electronic properties of the 2D perovskites with pure single phase is essential for improving the performance of the optoelectronic devices and designing devices with new architectures. Investigating the optical and electronic properties of these materials with pure single phase is required to obtain pure single phase 2D perovskites. Here, we report on an alternative approach to fabricate (C4H9NH3)2(CH3NH3) n-1Pb n I3n+1 microplates with pure single n-number perovskite phase for n  >  2 by mechanical exfoliation. Micro-photoluminescence and absorption spectroscopy studies reveal that the as-synthesized 2D perovskite plates for n  >  2 are comprised by dominant n-number phase and small inclusions of hybrid perovskite phases with different n values, which is supported by excitation power dependent photoluminescence. By mechanical exfoliation method, 2D perovskite microplates with the thickness of around 20 nm are obtained, which surprisingly have single n-number perovskite phase for n  =  2-5. In addition, we have demonstrated that the exfoliated 2D perovskite microplates can be integrated with other 2D layered materials such as boron nitride, and are able to be transferred to prefabricated electrodes for photodetections. Our studies not only provide a strategy to prepare 2D perovskites with a single n-number perovskite phase allowing us to extract the basic optical and electronic parameters of pure phase perovskites, but also demonstrate the possibility to integrate the 2D perovskites with other 2D layered materials to extend the device’s functionalities.

Hepatic DNA adduct dosimetry in rats fed tamoxifen: a comparison of methods.

PubMed

Schild, Laura J; Phillips, David H; Osborne, Martin R; Hewer, Alan; Beland, Frederick A; Churchwell, Mona I; Brown, Karen; Gaskell, Margaret; Wright, Elizabeth; Poirier, Miriam C

2005-03-01

Liver homogenates from rats fed tamoxifen (TAM) in the diet were shared among four different laboratories. TAM-DNA adducts were assayed by high pressure liquid chromatography-electrospray tandem mass spectrometry (HPLC-ES-MS/MS), TAM-DNA chemiluminescence immunoassay (TAM-DNA CIA), and (32)P-postlabeling with either thin layer ((32)P-P-TLC) or liquid chromatography ((32)P-P-HPLC) separation. In the first study, rats were fed a diet containing 500 p.p.m. TAM for 2 months, and the values for measurements of the (E)-alpha-(deoxyguanosin-N(2)-yl)-tamoxifen (dG-N(2)-TAM) adduct in replicate rat livers varied by 3.5-fold when quantified using 'in house' TAM-DNA standards, or other approaches where appropriate. In the second study, rats were fed 0, 50, 250 or 500 p.p.m. TAM for 2 months, and TAM-DNA values were quantified using both 'in house' approaches as well as a newly synthesized [N-methyl-(3)H]TAM-DNA standard that was shared among all the participating groups. In the second study, the total TAM-DNA adduct values varied by 2-fold, while values for the dG-N(2)-TAM varied by 2.5-fold. Ratios of dG-N(2)-TAM:(E)-alpha-(deoxyguanosin-N(2)-yl)-N-desmethyltamoxifen (dG-N(2)-N-desmethyl-TAM) in the second study were approximately 1:1 over the range of doses examined. The study demonstrated a remarkably good agreement for TAM-DNA adduct measurements among the diverse methods employed.

Theoretical transition probabilities, oscillator strengths, and radiative lifetimes of levels in Pb IV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alonso-Medina, A.; Colon, C., E-mail: cristobal.colon@upm.e; Porcher, P.

2011-01-15

Transition probabilities and oscillator strengths of 176 spectral lines with astrophysical interest arising from 5d{sup 10}ns (n = 7,8), 5d{sup 10}np (n = 6,7), 5d{sup 10}nd (n = 6,7), 5d{sup 10}5f, 5d{sup 10}5g, 5d{sup 10}nh (n = 6,7,8), 5d{sup 9}6s{sup 2}, and 5d{sup 9}6s6p configurations, and radiative lifetimes for 43 levels of Pb IV, have been calculated. These values were obtained in intermediate coupling (IC) and using relativistic Hartree-Fock calculations including core-polarization effects. For the IC calculations, we use the standard method of least-square fitting from experimental energy levels by means of the Cowan computer code. The inclusion in thesemore » calculations of the 5d{sup 10}7p and 5d{sup 10}5f configurations has facilitated a complete assignment of the energy levels in the Pb IV. Transition probabilities, oscillator strengths, and radiative lifetimes obtained are generally in good agreement with the experimental data.« less

The Ultimate Pile Bearing Capacity from Conventional and Spectral Analysis of Surface Wave (SASW) Measurements

NASA Astrophysics Data System (ADS)

Faizah Bawadi, Nor; Anuar, Shamilah; Rahim, Mustaqqim A.; Mansor, A. Faizal

2018-03-01

A conventional and seismic method for determining the ultimate pile bearing capacity was proposed and compared. The Spectral Analysis of Surface Wave (SASW) method is one of the non-destructive seismic techniques that do not require drilling and sampling of soils, was used in the determination of shear wave velocity (Vs) and damping (D) profile of soil. The soil strength was found to be directly proportional to the Vs and its value has been successfully applied to obtain shallow bearing capacity empirically. A method is proposed in this study to determine the pile bearing capacity using Vs and D measurements for the design of pile and also as an alternative method to verify the bearing capacity from the other conventional methods of evaluation. The objectives of this study are to determine Vs and D profile through frequency response data from SASW measurements and to compare pile bearing capacities obtained from the method carried out and conventional methods. All SASW test arrays were conducted near the borehole and location of conventional pile load tests. In obtaining skin and end bearing pile resistance, the Hardin and Drnevich equation has been used with reference strains obtained from the method proposed by Abbiss. Back analysis results of pile bearing capacities from SASW were found to be 18981 kN and 4947 kN compared to 18014 kN and 4633 kN of IPLT with differences of 5% and 6% for Damansara and Kuala Lumpur test sites, respectively. The results of this study indicate that the seismic method proposed in this study has the potential to be used in estimating the pile bearing capacity.

Coenzyme Q10 quantification in muscle, fibroblasts and cerebrospinal fluid by liquid chromatography/tandem mass spectrometry using a novel deuterated internal standard.

PubMed

Duberley, Kate E C; Hargreaves, Iain P; Chaiwatanasirikul, Korn-Anong; Heales, Simon J R; Land, John M; Rahman, Shamima; Mills, Kevin; Eaton, Simon

2013-05-15

Neurological dysfunction is common in primary coenzyme Q10 (2,3-dimethoxy, 5-methyl, 6-polyisoprene parabenzoquinone; CoQ10 ; ubiquinone) deficiencies, the most readily treatable subgroup of mitochondrial disorders. Therapeutic benefit from CoQ10 supplementation has also been noted in other neurodegenerative diseases. CoQ10 can be measured by high-performance liquid chromatography (HPLC) in plasma, muscle or leucocytes; however, there is no reliable method to quantify CoQ10 in cerebrospinal fluid (CSF). Additionally, many methods use CoQ9 , an endogenous ubiquinone in humans, as an internal standard. Deuterated CoQ10 (d6 -CoQ10 ) was synthesised by a novel, simple, method. Total CoQ10 was measured by liquid chromatography/tandem mass spectrometry (LC/MS/MS) using d6 -CoQ10 as internal standard and 5 mM methylamine as an ion-pairing reagent. Chromatography was performed using a Hypsersil GOLD C4 column (150 × 3 mm, 3 µm). CoQ10 levels were linear over a concentration range of 0-200 nM (R(2) = 0.9995). The lower limit of detection was 2 nM. The inter-assay coefficient of variation (CV) was 3.6% (10 nM) and 4.3% (20 nM), and intra-assay CV 3.4% (10 nM) and 3.6% (20 nM). Reference ranges were established for CoQ10 in CSF (5.7-8.7 nM; n = 17), fibroblasts (57.0-121.6 pmol/mg; n = 50) and muscle (187.3-430.1 pmol/mg; n = 15). Use of d6 -CoQ10 internal standard has enabled the development of a sensitive LC/MS/MS method to accurately determine total CoQ10 levels. Clinical applications of CSF CoQ10 determination include identification of patients with cerebral CoQ10 deficiency, and monitoring CSF CoQ10 levels following supplementation. Copyright © 2013 John Wiley & Sons, Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haghighat, A.; Sjoden, G.E.; Wagner, J.C.

In the past 10 yr, the Penn State Transport Theory Group (PSTTG) has concentrated its efforts on developing accurate and efficient particle transport codes to address increasing needs for efficient and accurate simulation of nuclear systems. The PSTTG's efforts have primarily focused on shielding applications that are generally treated using multigroup, multidimensional, discrete ordinates (S{sub n}) deterministic and/or statistical Monte Carlo methods. The difficulty with the existing public codes is that they require significant (impractical) computation time for simulation of complex three-dimensional (3-D) problems. For the S{sub n} codes, the large memory requirements are handled through the use of scratchmore » files (i.e., read-from and write-to-disk) that significantly increases the necessary execution time. Further, the lack of flexible features and/or utilities for preparing input and processing output makes these codes difficult to use. The Monte Carlo method becomes impractical because variance reduction (VR) methods have to be used, and normally determination of the necessary parameters for the VR methods is very difficult and time consuming for a complex 3-D problem. For the deterministic method, the authors have developed the 3-D parallel PENTRAN (Parallel Environment Neutral-particle TRANsport) code system that, in addition to a parallel 3-D S{sub n} solver, includes pre- and postprocessing utilities. PENTRAN provides for full phase-space decomposition, memory partitioning, and parallel input/output to provide the capability of solving large problems in a relatively short time. Besides having a modular parallel structure, PENTRAN has several unique new formulations and features that are necessary for achieving high parallel performance. For the Monte Carlo method, the major difficulty currently facing most users is the selection of an effective VR method and its associated parameters. For complex problems, generally, this process is very time consuming and may be complicated due to the possibility of biasing the results. In an attempt to eliminate this problem, the authors have developed the A{sup 3}MCNP (automated adjoint accelerated MCNP) code that automatically prepares parameters for source and transport biasing within a weight-window VR approach based on the S{sub n} adjoint function. A{sup 3}MCNP prepares the necessary input files for performing multigroup, 3-D adjoint S{sub n} calculations using TORT.« less

Oncoprotein kinase

DOEpatents

Karin, Michael; Hibi, Masahiko; Lin, Anning

2001-02-27

An isolated polypeptide (JNK) characterized by having a molecular weight of 46 kD or 55 kD as determined by reducing SDS-PAGE, having serine and theonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Oncoprotein protein kinase

DOEpatents

Karin, Michael; Hibi, Masahiko; Lin, Anning

1999-01-01

An isolated polypeptide (JNK) characterized by having a molecular weight of 46 kD or 55 kD as determined by reducing SDS-PAGE, having serine and theonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Simultaneous quantification of twenty Amadori products in soy sauce using liquid chromatography-tandem mass spectrometry.

PubMed

Katayama, Hiroshi; Tatemichi, Yuki; Nakajima, Ayako

2017-08-01

A liquid chromatography-tandem mass spectrometry method using a pentafluorophenylpropyl-bonded silica column was developed to simultaneously quantify twenty Amadori products (APs), including N-(1-Deoxy-d-fructosyl-1-yl)-l-isoleucine (Fru-Ile) and N-(1-Deoxy-d-fructosyl-1-yl)-l-leucine (Fru-Leu), in soy sauce, without the need for an ion-pairing reagent or sample derivatization. The method was applied to six types of soy sauce, to determine the total AP levels and the levels of individual APs. The level of total APs widely varied between the eight samples, from 358mg/L to 24347mg/L. The concentrations of N-ε-(1-deoxy-d-fructosyl-1-yl)-l-lysine (Fru-Lys) and N-(1-deoxy-d-fructosyl-1-yl)-l-pyroglutamic acid (Fru-pGlu) were the highest among the APs and the level of Fru-pGlu was similar to that of Fru-Lys. Furthermore, fermentation periods of up to six months greatly influenced AP levels in soy sauce but the levels remained constant thereafter. Thermal treatment of soy sauce had little effect on AP levels. Copyright © 2017. Published by Elsevier Ltd.

Development of ingan quantum dots by the Stranski-Krastanov method and droplet heteroepitaxy

NASA Astrophysics Data System (ADS)

Woodward, Jeffrey Michael

The development of InGaN quantum dots (QDs) is both scienti?cally challenging and promising for applications in visible spectrum LEDs, lasers, detectors, electroabsorption modulators and photovoltaics. Such QDs are typically grown using the Stranski-Krastanov (SK) growth mode, in which accumulated in-plane compressive strain induces a transition from 2D to 3D growth. This method has a number of inherent limitations, including the unavoidable formation of a 2D wetting layer and the di?culty of controlling the composition, areal density, and size of the dots. In this research, I have developed InGaN QDs by two methods using a plasma-assisted molecular beam epitaxy reactor. In the ?rst method, InGaN QDs were formed by SK growth mode on (0001) GaN/sapphire. In the second, I have addressed the limitations of the SK growth of InGaN QDs by developing a novel alternative method, which was utilized to grow on both (0001) GaN/sapphire and AlN/sapphire. This method relies upon the ability to form thermodynamically stable In-Ga liquid solutions throughout the entire compositional range at relatively low temperatures. Upon simultaneous or sequential deposition of In and Ga on a substrate, the adatoms form a liquid solution, whose composition is controlled by the ratio of the fluxes of the two constituents FIn/(FIn+FGa ). Depending on the interfacial free energy between the liquid deposit and substrate, the liquid deposit and vapor, and the vapor and substrate, the liquid deposit forms Inx-Ga1- x nano-droplets on the substrate. These nano-droplets convert into InxGa1-xN QDs upon exposure to nitrogen RF plasma. InGaN QDs produced by both methods were investigated in-situ by reflection high-energy electron diffraction and ex-situ by atomic force microscopy, field emission scanning electron microscopy, transmission electron microscopy, high resolution x-ray diffraction, and grazing incidence small angle x-ray scattering. The optical activity and device potential of the QDs were investigated by photoluminescence measurements and the formation and evaluation of PIN devices (in which the intrinsic region contains QDs embedded within a higher bandgap matrix). InGaN QDs with areal densities ranging from 109 to 1011 cm -2 and diameters ranging from 11 to 39 nm were achieved.

5-D interpolation with wave-front attributes

NASA Astrophysics Data System (ADS)

Xie, Yujiang; Gajewski, Dirk

2017-11-01

Most 5-D interpolation and regularization techniques reconstruct the missing data in the frequency domain by using mathematical transforms. An alternative type of interpolation methods uses wave-front attributes, that is, quantities with a specific physical meaning like the angle of emergence and wave-front curvatures. In these attributes structural information of subsurface features like dip and strike of a reflector are included. These wave-front attributes work on 5-D data space (e.g. common-midpoint coordinates in x and y, offset, azimuth and time), leading to a 5-D interpolation technique. Since the process is based on stacking next to the interpolation a pre-stack data enhancement is achieved, improving the signal-to-noise ratio (S/N) of interpolated and recorded traces. The wave-front attributes are determined in a data-driven fashion, for example, with the Common Reflection Surface (CRS method). As one of the wave-front-attribute-based interpolation techniques, the 3-D partial CRS method was proposed to enhance the quality of 3-D pre-stack data with low S/N. In the past work on 3-D partial stacks, two potential problems were still unsolved. For high-quality wave-front attributes, we suggest a global optimization strategy instead of the so far used pragmatic search approach. In previous works, the interpolation of 3-D data was performed along a specific azimuth which is acceptable for narrow azimuth acquisition but does not exploit the potential of wide-, rich- or full-azimuth acquisitions. The conventional 3-D partial CRS method is improved in this work and we call it as a wave-front-attribute-based 5-D interpolation (5-D WABI) as the two problems mentioned above are addressed. Data examples demonstrate the improved performance by the 5-D WABI method when compared with the conventional 3-D partial CRS approach. A comparison of the rank-reduction-based 5-D seismic interpolation technique with the proposed 5-D WABI method is given. The comparison reveals that there are significant advantages for steep dipping events using the 5-D WABI method when compared to the rank-reduction-based 5-D interpolation technique. Diffraction tails substantially benefit from this improved performance of the partial CRS stacking approach while the CPU time is comparable to the CPU time consumed by the rank-reduction-based method.

Characterization technique for detection of atom-size crystalline defects and strains using two-dimensional fast-Fourier-transform sampling Moiré method

NASA Astrophysics Data System (ADS)

Kodera, Masako; Wang, Qinghua; Ri, Shien; Tsuda, Hiroshi; Yoshioka, Akira; Sugiyama, Toru; Hamamoto, Takeshi; Miyashita, Naoto

2018-04-01

Recently, we have developed a two-dimensional (2D) fast-Fourier-transform (FFT) sampling Moiré technique to visually and quantitatively determine the locations of minute defects in a transmission electron microscopy (TEM) image. We applied this technique for defect detection with GaN high electron mobility transistor (HEMT) devices, and successfully and clearly visualized atom-size defects in AlGaN/GaN crystalline structures. The defect density obtained in the AlGaN/GaN structures is ∼1013 counts/cm2. In addition, we have successfully confirmed that the distribution and number of defects closely depend on the process conditions. Thus, this technique is quite useful for a device development. Moreover, the strain fields in an AlGaN/GaN crystal were effectively calculated with nm-scale resolution using this method. We also demonstrated that this sampling Moiré technique is applicable to silicon devices, which have principal directions different from those of AlGaN/GaN crystals. As a result, we believe that the 2D FFT sampling Moiré method has great potential applications to the discovery of new as yet unknown phenomena occurring between the characteristics of a crystalline material and device performance.

Anti-leucine rich glioma inactivated 1 protein and anti-N-methyl-D-aspartate receptor encephalitis show distinct patterns of brain glucose metabolism in 18F-fluoro-2-deoxy-d-glucose positron emission tomography

PubMed Central

2014-01-01

Background Pathogenic autoantibodies targeting the recently identified leucine rich glioma inactivated 1 protein and the subunit 1 of the N-methyl-D-aspartate receptor induce autoimmune encephalitis. A comparison of brain metabolic patterns in 18F-fluoro-2-deoxy-d-glucose positron emission tomography of anti-leucine rich glioma inactivated 1 protein and anti-N-methyl-D-aspartate receptor encephalitis patients has not been performed yet and shall be helpful in differentiating these two most common forms of autoimmune encephalitis. Methods The brain 18F-fluoro-2-deoxy-d-glucose uptake from whole-body positron emission tomography of six anti-N-methyl-D-aspartate receptor encephalitis patients and four patients with anti-leucine rich glioma inactivated 1 protein encephalitis admitted to Hannover Medical School between 2008 and 2012 was retrospectively analyzed and compared to matched controls. Results Group analysis of anti-N-methyl-D-aspartate encephalitis patients demonstrated regionally limited hypermetabolism in frontotemporal areas contrasting an extensive hypometabolism in parietal lobes, whereas the anti-leucine rich glioma inactivated 1 protein syndrome was characterized by hypermetabolism in cerebellar, basal ganglia, occipital and precentral areas and minor frontomesial hypometabolism. Conclusions This retrospective 18F-fluoro-2-deoxy-d-glucose positron emission tomography study provides novel evidence for distinct brain metabolic patterns in patients with anti-leucine rich glioma inactivated 1 protein and anti-N-methyl-D-aspartate receptor encephalitis. PMID:24950993

Polycyclic High Energy Oxidizers.

DTIC Science & Technology

1983-04-01

D -A128 309 P0 YCYCC HIGH ENER G OXIDIZERS(U) MORTON THIOKOL INC 1/r BRIGHAMCIT UT WASATCH DIV J C HINSHAW APR 83 I N00014-8N C 0204 JNCLASS4FIED /1/9...instability. 1. D . A. Cichra, J. Holden, and C. Dickenson Estimation of "Normal" Densities of hplosive Compounds from Empirical Atomic Volumes, Naval...Surface Weapons Center Report, ISWC TR-79-273, February 19,1980. 3 2. Estimated heats of formation are calculated using a method developed by A. D

A novel analytical method for d-glucosamine quantification and its application in the analysis of chitosan degradation by a minimal enzyme cocktail.

PubMed

Mekasha, Sophanit; Toupalová, Hana; Linggadjaja, Eka; Tolani, Harish A; Anděra, Ladislav; Arntzen, Magnus Ø; Vaaje-Kolstad, Gustav; Eijsink, Vincent G H; Agger, Jane W

2016-10-04

Enzymatic depolymerization of chitosan, a β-(1,4)-linked polycationic polysaccharide composed of d-glucosamine (GlcN) and N-acetyl-d-glucosamine (GlcNAc) provides a possible route to the exploitation of chitin-rich biomass. Complete conversion of chitosan to mono-sugars requires the synergistic action of endo- and exo- chitosanases. In the present study we have developed an efficient and cost-effective chitosan-degrading enzyme cocktail containing only two enzymes, an endo-attacking bacterial chitosanase, ScCsn46A, from Streptomyces coelicolor, and an exo-attacking glucosamine specific β-glucosaminidase, Tk-Glm, from the archaeon Thermococcus kodakarensis KOD1. Moreover, we developed a fast, reliable quantitative method for analysis of GlcN using high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The sensitivity of this method is high and less than 50 pmol was easily detected, which is about 1000-fold better than the sensitivity of more commonly used detection methods based on refractive index. We also obtained qualitative insight into product development during the enzymatic degradation reaction by means of ElectroSpray Ionization-Mass Spectrometry (ESI-MS). Copyright © 2016 Elsevier Ltd. All rights reserved.

Rapid identification of fungal pathogens in BacT/ALERT, BACTEC, and BBL MGIT media using polymerase chain reaction and DNA sequencing of the internal transcribed spacer regions.

PubMed

Pryce, Todd M; Palladino, Silvano; Price, Diane M; Gardam, Dianne J; Campbell, Peter B; Christiansen, Keryn J; Murray, Ronan J

2006-04-01

We report a direct polymerase chain reaction/sequence (d-PCRS)-based method for the rapid identification of clinically significant fungi from 5 different types of commercial broth enrichment media inoculated with clinical specimens. Media including BacT/ALERT FA (BioMérieux, Marcy l'Etoile, France) (n = 87), BACTEC Plus Aerobic/F (Becton Dickinson, Microbiology Systems, Sparks, MD) (n = 16), BACTEC Peds Plus/F (Becton Dickinson) (n = 15), BACTEC Lytic/10 Anaerobic/F (Becton Dickinson) (n = 11) bottles, and BBL MGIT (Becton Dickinson) (n = 11) were inoculated with specimens from 138 patients. A universal DNA extraction method was used combining a novel pretreatment step to remove PCR inhibitors with a column-based DNA extraction kit. Target sequences in the noncoding internal transcribed spacer regions of the rRNA gene were amplified by PCR and sequenced using a rapid (24 h) automated capillary electrophoresis system. Using sequence alignment software, fungi were identified by sequence similarity with sequences derived from isolates identified by upper-level reference laboratories or isolates defined as ex-type strains. We identified Candida albicans (n = 14), Candida parapsilosis (n = 8), Candida glabrata (n = 7), Candida krusei (n = 2), Scedosporium prolificans (n = 4), and 1 each of Candida orthopsilosis, Candida dubliniensis, Candida kefyr, Candida tropicalis, Candida guilliermondii, Saccharomyces cerevisiae, Cryptococcus neoformans, Aspergillus fumigatus, Histoplasma capsulatum, and Malassezia pachydermatis by d-PCRS analysis. All d-PCRS identifications from positive broths were in agreement with the final species identification of the isolates grown from subculture. Earlier identification of fungi using d-PCRS may facilitate prompt and more appropriate antifungal therapy.

Nano-graphene oxide and vitamin D delivery

NASA Astrophysics Data System (ADS)

Mahdavi, Reza; Solati-Hashjin, Mehran; Omidi, Meisam; Khojasteh, Arash; Fayyazbakhsh, Fateme

2018-01-01

One of the most interesting and recent insights into biomimetic scaffold nano-biomaterial is smart scaffolding with targeted drug delivery ability. In recent decades, the use of graphene-based materials, such as nano-graphene oxide (nGO), as a drug carrier with amphiphilic properties, has attracted considerable attention of scientists and researchers in this field. In addition, one of the important global problems is increased vitamin D deficiency, particularly in pregnant and postmenopausal women. Therefore, in this work, by considering hydrophobic properties of vitamin D, we attempted to examine its loading and release both in the presence of surfactant and surfactant-free nGO-aqueous solution. At first, nGO powder was synthesized by the modified Hummer's method. After the preparation of vitamin D and Tween 80 (TW) solution, they were added to nGO aqueous solution. Simultaneously, the next vitamin D and nGO aqueous solution was prepared in a surfactant-free mode. In order to evaluate the loading content, both solutions were centrifuged, and their supernatant was analyzed by UV-Visible spectroscopy. Additionally, FTIR spectroscopy was employed to determine the TW 80 effects on vitamin D and nGO. The results have shown that vitamin D loading in surfactant-free solution was approximately 0% while in the presence of TW 80 it was 75.37% ± 4.12. Therefore, the combination of vitamin D, TW 80, and nGO can be a suitable candidate for carrying hydrophobic drugs in smart scaffolding, especially in bone tissue engineering.

Annotating Enzymes of Uncertain Function: The Deacylation of d-Amino Acids by Members of the Amidohydrolase Superfamily

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cummings, J.; Fedorov, A; Xu, C

The catalytic activities of three members of the amidohydrolase superfamily were discovered using amino acid substrate libraries. Bb3285 from Bordetella bronchiseptica, Gox1177 from Gluconobacter oxidans, and Sco4986 from Streptomyces coelicolor are currently annotated as d-aminoacylases or N-acetyl-d-glutamate deacetylases. These three enzymes are 22-34% identical to one another in amino acid sequence. Substrate libraries containing nearly all combinations of N-formyl-d-Xaa, N-acetyl-d-Xaa, N-succinyl-d-Xaa, and l-Xaa-d-Xaa were used to establish the substrate profiles for these enzymes. It was demonstrated that Bb3285 is restricted to the hydrolysis of N-acyl-substituted derivatives of d-glutamate. The best substrates for this enzyme are N-formyl-d-glutamate (k{sub cat}/K{sub m} =more » 5.8 x 10{sup 6} M{sup -1} s{sup -1}), N-acetyl-d-glutamate (k{sub cat}/K{sub m} = 5.2 x 10{sup 6} M{sup -1} s{sup -1}), and l-methionine-d-glutamate (k{sub cat}/K{sub m} = 3.4 x 10{sup 5} M{sup -1} s{sup -1}). Gox1177 and Sco4986 preferentially hydrolyze N-acyl-substituted derivatives of hydrophobic d-amino acids. The best substrates for Gox1177 are N-acetyl-d-leucine (k{sub cat}/K{sub m} = 3.2 x 104 M{sup -1} s-1), N-acetyl-d-tryptophan (kcat/Km = 4.1 x 104 M-1 s-1), and l-tyrosine-d-leucine (kcat/Km = 1.5 x 104 M-1 s-1). A fourth protein, Bb2785 from B. bronchiseptica, did not have d-aminoacylase activity. The best substrates for Sco4986 are N-acetyl-d-phenylalanine and N-acetyl-d-tryptophan. The three-dimensional structures of Bb3285 in the presence of the product acetate or a potent mimic of the tetrahedral intermediate were determined by X-ray diffraction methods. The side chain of the d-glutamate moiety of the inhibitor is ion-paired to Arg-295, while the {alpha}-carboxylate is ion-paired with Lys-250 and Arg-376. These results have revealed the chemical and structural determinants for substrate specificity in this protein. Bioinformatic analyses of an additional {approx}250 sequences identified as members of this group suggest that there are no simple motifs that allow prediction of substrate specificity for most of these unknowns, highlighting the challenges for computational annotation of some groups of homologous proteins.« less

Histochemistry of glycoconjugates in the skin of the bovine muzzle, with special reference to glandular structures.

PubMed

Meyer, W; Tsukise, A

1989-01-01

The distribution of glycoconjugates in the muzzle of young adult Holstein cows has been studied by means of selected light-microscopic histochemical methods, including lectin histochemistry. In the skin layers, strong reactions were confined to intercellular substances in between the cells of the vital epidermis, exhibiting neutral glycoconjugates mainly with alpha-D-galactosyl and N-acetyl-D-galactosaminyl residues. In the nasolabial glands, distinctly positive staining for neutral glycoproteins with various saccharide residues (alpha-D-galactose, alpha-N-acetylgalactosamine, D-galactose-beta(1----3)D-N-acetylgalactosamine, beta-D-galactose), and for smaller amounts of acidic glycoconjugates, was found in the secretory cells and the luminal secretion. The cells of the excretory duct system showed weak to moderate reactions (alpha-D-galactose, beta-D-galactose), only the collecting ducts reacted positively for acidic glycoproteins with sialyl residues. The results obtained are discussed in view of muzzle function, with special reference to the salivary nature of the secretion of bovine nasolabial glands.

Circulating 25-hydroxyvitamin D and the risk of rarer cancers: Design and methods of the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers.

PubMed

Gallicchio, Lisa; Helzlsouer, Kathy J; Chow, Wong-Ho; Freedman, D Michal; Hankinson, Susan E; Hartge, Patricia; Hartmuller, Virginia; Harvey, Chinonye; Hayes, Richard B; Horst, Ronald L; Koenig, Karen L; Kolonel, Laurence N; Laden, Francine; McCullough, Marjorie L; Parisi, Dominick; Purdue, Mark P; Shu, Xiao-Ou; Snyder, Kirk; Stolzenberg-Solomon, Rachael Z; Tworoger, Shelley S; Varanasi, Arti; Virtamo, Jarmo; Wilkens, Lynne R; Xiang, Yong-Bing; Yu, Kai; Zeleniuch-Jacquotte, Anne; Zheng, Wei; Abnet, Christian C; Albanes, Demetrius; Bertrand, Kimberly; Weinstein, Stephanie J

2010-07-01

The Cohort Consortium Vitamin D Pooling Project of Rarer Cancers (VDPP), a consortium of 10 prospective cohort studies from the United States, Finland, and China, was formed to examine the associations between circulating 25-hydroxyvitamin D (25(OH)D) concentrations and the risk of rarer cancers. Cases (total n = 5,491) included incident primary endometrial (n = 830), kidney (n = 775), ovarian (n = 516), pancreatic (n = 952), and upper gastrointestinal tract (n = 1,065) cancers and non-Hodgkin lymphoma (n = 1,353) diagnosed in the participating cohorts. At least 1 control was matched to each case on age, date of blood collection (1974-2006), sex, and race/ethnicity (n = 6,714). Covariate data were obtained from each cohort in a standardized manner. The majority of the serum or plasma samples were assayed in a central laboratory using a direct, competitive chemiluminescence immunoassay on the DiaSorin LIAISON platform (DiaSorin, Inc., Stillwater, Minnesota). Masked quality control samples included serum standards from the US National Institute of Standards and Technology. Conditional logistic regression analyses were conducted using clinically defined cutpoints, with 50-<75 nmol/L as the reference category. Meta-analyses were also conducted using inverse-variance weights in random-effects models. This consortium approach permits estimation of the association between 25(OH)D and several rarer cancers with high accuracy and precision across a wide range of 25(OH)D concentrations.

Circulating 25-Hydroxyvitamin D and the Risk of Rarer Cancers: Design and Methods of the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers

PubMed Central

Gallicchio, Lisa; Helzlsouer, Kathy J.; Chow, Wong-Ho; Freedman, D. Michal; Hankinson, Susan E.; Hartge, Patricia; Hartmuller, Virginia; Harvey, Chinonye; Hayes, Richard B.; Horst, Ronald L.; Koenig, Karen L.; Kolonel, Laurence N.; Laden, Francine; McCullough, Marjorie L.; Parisi, Dominick; Purdue, Mark P.; Shu, Xiao-Ou; Snyder, Kirk; Stolzenberg-Solomon, Rachael Z.; Tworoger, Shelley S.; Varanasi, Arti; Virtamo, Jarmo; Wilkens, Lynne R.; Xiang, Yong-Bing; Yu, Kai; Zeleniuch-Jacquotte, Anne; Zheng, Wei; Abnet, Christian C.; Albanes, Demetrius; Bertrand, Kimberly; Weinstein, Stephanie J.

2010-01-01

The Cohort Consortium Vitamin D Pooling Project of Rarer Cancers (VDPP), a consortium of 10 prospective cohort studies from the United States, Finland, and China, was formed to examine the associations between circulating 25-hydroxyvitamin D (25(OH)D) concentrations and the risk of rarer cancers. Cases (total n = 5,491) included incident primary endometrial (n = 830), kidney (n = 775), ovarian (n = 516), pancreatic (n = 952), and upper gastrointestinal tract (n = 1,065) cancers and non-Hodgkin lymphoma (n = 1,353) diagnosed in the participating cohorts. At least 1 control was matched to each case on age, date of blood collection (1974–2006), sex, and race/ethnicity (n = 6,714). Covariate data were obtained from each cohort in a standardized manner. The majority of the serum or plasma samples were assayed in a central laboratory using a direct, competitive chemiluminescence immunoassay on the DiaSorin LIAISON platform (DiaSorin, Inc., Stillwater, Minnesota). Masked quality control samples included serum standards from the US National Institute of Standards and Technology. Conditional logistic regression analyses were conducted using clinically defined cutpoints, with 50–<75 nmol/L as the reference category. Meta-analyses were also conducted using inverse-variance weights in random-effects models. This consortium approach permits estimation of the association between 25(OH)D and several rarer cancers with high accuracy and precision across a wide range of 25(OH)D concentrations. PMID:20562188

A Unified Approach to UXO Discrimination Using the Method of Auxiliary Sources

DTIC Science & Technology

2006-10-12

0 and is sin(mφ) for p = 1, bpmn the spheroidal expansion coefficients. Eq. (2.1) is a decomposition of a primary magnetic potential into a number of...spheroidal expansion coefficients bpmn can be derived as bpmn = − 2n+ 1 γπH0dP ′mn (ξ0) (n−m)! (n+m)! ∫ 1 −1 Pmn (η)hξ ∫ 2π 0 Hprξ (η, ξ0, φ)Tpm(φ)dφdη...the object’s response for each pmn excitation mode (Chen et al., 2004; Sun et al., 2005), i.e., Hsc(r) = M ∑ m=0 N ∑ n=m 1 ∑ p=0 bpmn Nq ∑ i=1 qpmni G

T2-weighted four dimensional magnetic resonance imaging with result-driven phase sorting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Yilin; Yin, Fang-Fang; Cai, Jing, E-mail: jing.cai@duke.edu

2015-08-15

Purpose: T2-weighted MRI provides excellent tumor-to-tissue contrast for target volume delineation in radiation therapy treatment planning. This study aims at developing a novel T2-weighted retrospective four dimensional magnetic resonance imaging (4D-MRI) phase sorting technique for imaging organ/tumor respiratory motion. Methods: A 2D fast T2-weighted half-Fourier acquisition single-shot turbo spin-echo MR sequence was used for image acquisition of 4D-MRI, with a frame rate of 2–3 frames/s. Respiratory motion was measured using an external breathing monitoring device. A phase sorting method was developed to sort the images by their corresponding respiratory phases. Besides, a result-driven strategy was applied to effectively utilize redundantmore » images in the case when multiple images were allocated to a bin. This strategy, selecting the image with minimal amplitude error, will generate the most representative 4D-MRI. Since we are using a different image acquisition mode for 4D imaging (the sequential image acquisition scheme) with the conventionally used cine or helical image acquisition scheme, the 4D dataset sufficient condition was not obviously and directly predictable. An important challenge of the proposed technique was to determine the number of repeated scans (N{sub R}) required to obtain sufficient phase information at each slice position. To tackle this challenge, the authors first conducted computer simulations using real-time position management respiratory signals of the 29 cancer patients under an IRB-approved retrospective study to derive the relationships between N{sub R} and the following factors: number of slices (N{sub S}), number of 4D-MRI respiratory bins (N{sub B}), and starting phase at image acquisition (P{sub 0}). To validate the authors’ technique, 4D-MRI acquisition and reconstruction were simulated on a 4D digital extended cardiac-torso (XCAT) human phantom using simulation derived parameters. Twelve healthy volunteers were involved in an IRB-approved study to investigate the feasibility of this technique. Results: 4D data acquisition completeness (C{sub p}) increases as NR increases in an inverse-exponential fashion (C{sub p} = 100 − 99 × exp(−0.18 × N{sub R}), when N{sub B} = 6, fitted using 29 patients’ data). The N{sub R} required for 4D-MRI reconstruction (defined as achieving 95% completeness, C{sub p} = 95%, N{sub R} = N{sub R,95}) is proportional to N{sub B} (N{sub R,95} ∼ 2.86 × N{sub B}, r = 1.0), but independent of N{sub S} and P{sub 0}. Simulated XCAT 4D-MRI showed a clear pattern of respiratory motion. Tumor motion trajectories measured on 4D-MRI were comparable to the average input signal, with a mean relative amplitude error of 2.7% ± 2.9%. Reconstructed 4D-MRI for healthy volunteers illustrated clear respiratory motion on three orthogonal planes, with minimal image artifacts. The artifacts were presumably caused by breathing irregularity and incompleteness of data acquisition (95% acquired only). The mean relative amplitude error between critical structure trajectory and average breathing curve for 12 healthy volunteers is 2.5 ± 0.3 mm in superior–inferior direction. Conclusions: A novel T2-weighted retrospective phase sorting 4D-MRI technique has been developed and successfully applied on digital phantom and healthy volunteers.« less

Transport Equations Resolution By N-BEE Anti-Dissipative Scheme In 2D Model Of Low Pressure Glow Discharge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kraloua, B.; Hennad, A.

The aim of this paper is to determine electric and physical properties by 2D modelling of glow discharge low pressure in continuous regime maintained by term constant source. This electric discharge is confined in reactor plan-parallel geometry. This reactor is filled by Argon monatomic gas. Our continuum model the order two is composed the first three moments the Boltzmann's equations coupled with Poisson's equation by self consistent method. These transport equations are discretized by the finite volumes method. The equations system is resolved by a new technique, it is about the N-BEE explicit scheme using the time splitting method.

Identification or Development of Chemical Analysis Methods for Plants and Animal Tissues

DTIC Science & Technology

1981-01-01

Report No. DRXTH-TE-CR-80086 [E EMWSTEEACISITE - IDENTIFICATION OR DEVELOPMENT OF CHEMICAL ANALYSISI METHODS FOR PLANTS AND ANIMAL TISSUES D l...86i 4TITLE (ansdo"t) TYPE or" P 4. Iih~iti.)Final epwt. )9 A4,417 ~, Identlifiation or Development of Chemical I-g 9 O d 18 Analysis Methods for Plants...n TN oT sacmpihdo in. wEr DContinng er adetcsr aid Iuent bybopkmertda lo aeo 1.5th 1/s deeipta24ndectr Tritrotasolsoepae d andT Boloia Matrc,, 1473

Artifact suppression in electron paramagnetic resonance imaging of 14N- and 15N-labeled nitroxyl radicals with asymmetric absorption spectra

NASA Astrophysics Data System (ADS)

Takahashi, Wataru; Miyake, Yusuke; Hirata, Hiroshi

2014-10-01

This article describes an improved method for suppressing image artifacts in the visualization of 14N- and 15N-labeled nitroxyl radicals in a single image scan using electron paramagnetic resonance (EPR). The purpose of this work was to solve the problem of asymmetric EPR absorption spectra in spectral processing. A hybrid function of Gaussian and Lorentzian lineshapes was used to perform spectral line-fitting to successfully separate the two kinds of nitroxyl radicals. This approach can process the asymmetric EPR absorption spectra of the nitroxyl radicals being measured, and can suppress image artifacts due to spectral asymmetry. With this improved visualization method and a 750-MHz continuous-wave EPR imager, a temporal change in the distributions of a two-phase paraffin oil and water/glycerin solution system was visualized using lipophilic and hydrophilic nitroxyl radicals, i.e., 2-(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxazolidinyloxy (16-DOXYL stearic acid) and 4-hydroxyl-2,2,6,6-tetramethylpiperidine-d17-1-15N-1-oxyl (TEMPOL-d17-15N). The results of the two-phase separation experiment verified that reasonable artifact suppression could be achieved by the present method that deals with asymmetric absorption spectra in the EPR imaging of 14N- and 15N-labeled nitroxyl radicals.

Manual Planimetry of the Medial Temporal Lobe Versus Automated Volumetry of the Hippocampus in the Diagnosis of Alzheimer's Disease.

PubMed

Menéndez González, Manuel; Suárez-Sanmartin, Esther; García, Ciara; Martínez-Camblor, Pablo; Westman, Eric; Simmons, Andy

2016-03-26

Though a disproportionate rate of atrophy in the medial temporal lobe (MTA) represents a reliable marker of Alzheimer's disease (AD) pathology, measurement of the MTA is not currently widely used in daily clinical practice. This is mainly because the methods available to date are sophisticated and difficult to implement in clinical practice (volumetric methods), are poorly explored (linear and planimetric methods), or lack objectivity (visual rating). Here, we aimed to compare the results of a manual planimetric measure (the yearly rate of absolute atrophy of the medial temporal lobe, 2D-yrA-MTL) with the results of an automated volumetric measure (the yearly rate of atrophy of the hippocampus, 3D-yrA-H). A series of 1.5T MRI studies on 290 subjects in the age range of 65-85 years, including patients with AD (n = 100), mild cognitive impairment (MCI) (n = 100), and matched controls (n = 90) from the AddNeuroMed study, were examined by two independent subgroups of researchers: one in charge of volumetric measures and the other in charge of planimetric measures. The means of both methods were significantly different between AD and the other two diagnostic groups. In the differential diagnosis of AD against controls, 3D-yrA-H performed significantly better than 2D-yrA-MTL while differences were not statistically significant in the differential diagnosis of AD against MCI. Automated volumetry of the hippocampus is superior to manual planimetry of the MTL in the diagnosis of AD. Nevertheless, the 2D-yrAMTL is a simpler method that could be easily implemented in clinical practice when volumetry is not available.

Determination of hydrogen/deuterium ratio with neutron measurements on MAST

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klimek, I., E-mail: iwona.klimek@physics.uu.se; Cecconello, M.; Ericsson, G.

2014-11-15

On MAST, compressional Alfvén eigenmodes can be destabilized by the presence of a sufficiently large population of energetic particles in the plasma. This dependence was studied in a series of very similar discharges in which increasing amounts of hydrogen were puffed into a deuterium plasma. A simple method to estimate the isotopic ratio n{sub H}/n{sub D} using neutron emission measurements is here described. The inferred isotopic ratio ranged from 0.0 to 0.6 and no experimental indication of changes in radial profile of n{sub H}/n{sub D} were observed. These findings are confirmed by TRANSP/NUBEAM simulations of the neutron emission.

Dielectrophoretic Field-Flow Fractionation System for Detection of Aquatic Toxicants

PubMed Central

Pui-ock, Sittisak; Ruchirawat, Mathuros; Gascoyne, Peter

2009-01-01

Dielectrophoretic field-flow fractionation (dFFF) was applied as a contact-free way to sense changes in the plasma membrane capacitances and conductivities of cultured human HL-60 cells in response to toxicant exposure. A micropatterned electrode imposed electric forces on cells in suspension in a parabolic flow profile as they moved through a thin chamber. Relative changes in the dFFF peak elution time, reflecting changes in cell membrane area and ion permeability, were measured as indices of response during the first 150 min of exposure to eight toxicants having different single or mixed modes of action (acrylonitrile, actinomycin D, carbon tetrachloride, endosulfan, N-nitroso-N-methylurea (NMU), paraquat dichloride, puromycin, and styrene oxide). The dFFF method was compared with the cell viability assay for all toxicants and with the mitochondrial potentiometric dye assay or DNA alkaline comet assay according to the mode of action of the specific agents. Except for low doses of nucleic acid-targeting agents (actinomycin D and NMU), the dFFF method detected all toxicants more sensitively than other assays, in some cases up to 105 times more sensitively than the viability approach. The results suggest the dFFF method merits additional study for possible applicability in toxicology. PMID:18788754

Magnetization induced by odd-frequency spin-triplet Cooper pairs in a Josephson junction with metallic trilayers

NASA Astrophysics Data System (ADS)

Hikino, S.; Yunoki, S.

2015-07-01

We theoretically study the magnetization inside a normal metal induced in an s -wave superconductor/ferromagnetic metal/normal metal/ferromagnetic metal/s -wave superconductor (S /F 1 /N /F 2 /S ) Josephson junction. Using the quasiclassical Green's function method, we show that the magnetization becomes finite inside the N . The origin of this magnetization is due to odd-frequency spin-triplet Cooper pairs formed by electrons of equal and opposite spins, which are induced by the proximity effect in the S /F 1 /N /F 2 /S junction. We find that the magnetization M (d ,θ ) in the N can be decomposed into two parts, M (d ,θ ) =MI(d ) +MII(d ,θ ) , where θ is the superconducting phase difference between the two S s and d is the thickness of N . The θ -independent magnetization MI(d ) exists generally in S /F junctions, while MII(d ,θ ) carries all θ dependence and represents the fingerprint of the phase coherence between the two S s in Josephson junctions. The θ dependence thus allows us to control the magnetization in the N by tuning θ for a fixed d . We show that the θ -independent magnetization MI(d ) weakly decreases with increasing d , while the θ -dependent magnetization MII(d ,θ ) rapidly decays with d . Moreover, we find that the time-averaged magnetization exhibits a discontinuous peak at each resonance dc voltage Vn=n ℏ ωS/2 e (n : integer) when dc voltage V as well as ac voltage vac(t ) with frequency ωS are both applied to the S /F 1 /N /F 2 /S junction. This is because MII(d ,θ ) oscillates generally in time t (ac magnetization) with d θ /d t =2 e [V +vac(t ) ]/ℏ and thus =0 , but can be converted into the time-independent dc magnetization for the dc voltage at Vn. We also discuss that the magnetization induced in the N can be measurably large in realistic systems. Therefore, the measurement of the induced magnetization serves as an alternative way to detect the phase coherence between the two S s in Josephson junctions. Our results also provide a basic concept for tunable magnetization in superconducting spintronics devices.

Stark widths and shifts for spectral lines of Sn IV

NASA Astrophysics Data System (ADS)

de Andrés-García, I.; Alonso-Medina, A.; Colón, C.

2016-01-01

In this paper, we present theoretical Stark widths and shifts calculated corresponding to 66 spectral lines of Sn IV. We use the Griem semi-empirical approach and the COWAN computer code. For the intermediate coupling calculations, the standard method of least-squares fitting from experimental energy levels was used. Data are presented for an electron density of 1017 cm-3 and temperatures T = 1.1-5.0 (104 K). The matrix elements used in these calculations have been determined from 34 configurations of Sn IV: 4d10ns(n = 5-10), 4d10nd(n = 5-8), 4d95s2, 4d95p2, 4d95s5d, 4d85s5p2 and 4d105g for even parity and 4d10np(n = 5-8), 4d10nf (n = 4-6), 4d95snp(n = 5-8), 4d85s25p and 4d95snf (n = 4-10) for odd parity. Also, in order to test the matrix elements used in our calculations, we present calculated values of radiative lifetimes of 14 levels of Sn IV. There is good agreement between our calculations and the experimental radiative lifetimes obtained from the bibliography. The spectral lines of Sn IV are observed in UV spectra of HD 149499 B obtained with the Far Ultraviolet Spectroscopic Explorer, the Goddard High Resolution Spectrograph and the International Ultraviolet Explorer. Theoretical trends of the Stark broadening parameter versus the temperature for relevant lines are presented. Also our values of Stark broadening parameters have been compared with the data available in the bibliography.

High-level SUMO-mediated fusion expression of ABP-dHC-cecropin A from multiple joined genes in Escherichia coli.

PubMed

Zhang, Jiaxin; Movahedi, Ali; Wei, Zhiheng; Sang, Ming; Wu, Xiaolong; Wang, Mengyang; Wei, Hui; Pan, Huixin; Yin, Tongming; Zhuge, Qiang

2016-09-15

The antimicrobial peptide ABP-dHC-cecropin A is a small cationic peptide with potent activity against a wide range of bacterial species. Evidence of antifungal activity has also been suggested; however, evaluation of this peptide has been limited due to the low expression of cecropin proteins in Escherichia coli. To improve the expression level of ABP-dHC-cecropin A in E. coli, tandem repeats of the ABP-dHC-cecropin A gene were constructed and expressed as fusion proteins (SUMO-nABP-dHC-cecropin, n = 1, 2, 3, 4) via pSUMO-nABP-dHC-cecropin A vectors (n = 1, 2, 3, 4). Comparison of the expression levels of soluble SUMO-nABP-dHC-cecropin A fusion proteins (n = 1, 2, 3, 4) suggested that BL21 (DE3)/pSUMO-3ABP-dHC-cecropin A is an ideal recombinant strain for ABP-dHC-cecropin A production. Under the selected conditions of cultivation and isopropylthiogalactoside (IPTG) induction, the expression level of ABP-dHC-cecropin A was as high as 65 mg/L, with ∼21.3% of the fusion protein in soluble form. By large-scale fermentation, protein production reached nearly 300 mg/L, which is the highest yield of ABP-dHC-cecropin A reported to date. In antibacterial experiments, the efficacy was approximately the same as that of synthetic ABP-dHC-cecropin A. This method provides a novel and effective means of producing large amounts of ABP-dHC-cecropin A. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical validation of coronal and sagittal spinal curve measurements based on three-dimensional vertebra vector parameters.

PubMed

Somoskeöy, Szabolcs; Tunyogi-Csapó, Miklós; Bogyó, Csaba; Illés, Tamás

2012-10-01

For many decades, visualization and evaluation of three-dimensional (3D) spinal deformities have only been possible by two-dimensional (2D) radiodiagnostic methods, and as a result, characterization and classification were based on 2D terminologies. Recent developments in medical digital imaging and 3D visualization techniques including surface 3D reconstructions opened a chance for a long-sought change in this field. Supported by a 3D Terminology on Spinal Deformities of the Scoliosis Research Society, an approach for 3D measurements and a new 3D classification of scoliosis yielded several compelling concepts on 3D visualization and new proposals for 3D classification in recent years. More recently, a new proposal for visualization and complete 3D evaluation of the spine by 3D vertebra vectors has been introduced by our workgroup, a concept, based on EOS 2D/3D, a groundbreaking new ultralow radiation dose integrated orthopedic imaging device with sterEOS 3D spine reconstruction software. Comparison of accuracy, correlation of measurement values, intraobserver and interrater reliability of methods by conventional manual 2D and vertebra vector-based 3D measurements in a routine clinical setting. Retrospective, nonrandomized study of diagnostic X-ray images created as part of a routine clinical protocol of eligible patients examined at our clinic during a 30-month period between July 2007 and December 2009. In total, 201 individuals (170 females, 31 males; mean age, 19.88 years) including 10 healthy athletes with normal spine and patients with adolescent idiopathic scoliosis (175 cases), adult degenerative scoliosis (11 cases), and Scheuermann hyperkyphosis (5 cases). Overall range of coronal curves was between 2.4 and 117.5°. Analysis of accuracy and reliability of measurements was carried out on a group of all patients and in subgroups based on coronal plane deviation: 0 to 10° (Group 1; n=36), 10 to 25° (Group 2; n=25), 25 to 50° (Group 3; n=69), 50 to 75° (Group 4; n=49), and above 75° (Group 5; n=22). All study subjects were examined by EOS 2D imaging, resulting in anteroposterior (AP) and lateral (LAT) full spine, orthogonal digital X-ray images, in standing position. Conventional coronal and sagittal curvature measurements including sagittal L5 vertebra wedges were determined by 3 experienced examiners, using traditional Cobb methods on EOS 2D AP and LAT images. Vertebra vector-based measurements were performed as published earlier, based on computer-assisted calculations of corresponding spinal curvature. Vertebra vectors were generated by dedicated software from sterEOS 3D spine models reconstructed from EOS 2D images by the same three examiners. Manual measurements were performed by each examiner, thrice for sterEOS 3D reconstructions and twice for vertebra vector-based measurements. Means comparison t test, Pearson bivariate correlation analysis, reliability analysis by intraclass correlation coefficients for intraobserver reproducibility and interrater reliability were performed using SPSS v16.0 software. In comparison with manual 2D methods, only small and nonsignificant differences were detectable in vertebra vector-based curvature data for coronal curves and thoracic kyphosis, whereas the found difference in L1-L5 lordosis values was shown to be strongly related to the magnitude of corresponding L5 wedge. Intraobserver reliability was excellent for both methods, and interrater reproducibility was consistently higher for vertebra vector-based methods that was also found to be unaffected by the magnitude of coronal curves or sagittal plane deviations. Vertebra vector-based angulation measurements could fully substitute conventional manual 2D measurements, with similar accuracy and higher intraobserver reliability and interrater reproducibility. Vertebra vectors represent a truly 3D solution for clear and comprehensible 3D visualization of spinal deformities while preserving crucial parametric information for vertebral size, 3D position, orientation, and rotation. The concept of vertebra vectors may serve as a starting point to a valid and clinically useful alternative for a new 3D classification of scoliosis. Copyright © 2012 Elsevier Inc. All rights reserved.

Application of unsymmetrical indirect covariance NMR methods to the computation of the (13)C <--> (15)N HSQC-IMPEACH and (13)C <--> (15)N HMBC-IMPEACH correlation spectra.

PubMed

Martin, Gary E; Hilton, Bruce D; Irish, Patrick A; Blinov, Kirill A; Williams, Antony J

2007-10-01

Utilization of long-range (1)H--(15)N heteronuclear chemical shift correlation has continually grown in importance since the first applications were reported in 1995. More recently, indirect covariance NMR methods have been introduced followed by the development of unsymmetrical indirect covariance processing methods. The latter technique has been shown to allow the calculation of hyphenated 2D NMR data matrices from more readily acquired nonhyphenated 2D NMR spectra. We recently reported the use of unsymmetrical indirect covariance processing to combine (1)H--(13)C GHSQC and (1)H--(15)N GHMBC long-range spectra to yield a (13)C--(15)N HSQC-HMBC chemical shift correlation spectrum that could not be acquired in a reasonable period of time without resorting to (15)N-labeled molecules. We now report the unsymmetrical indirect covariance processing of (1)H--(13)C GHMBC and (1)H--(15)N IMPEACH spectra to afford a (13)C--(15)N HMBC-IMPEACH spectrum that has the potential to span as many as six to eight bonds. Correlations for carbon resonances long-range coupled to a protonated carbon in the (1)H--(13)C HMBC spectrum are transferred via the long-range (1)H--(15)N coupling pathway in the (1)H--(15)N IMPEACH spectrum to afford a much broader range of correlation possibilities in the (13)C--(15)N HMBC-IMPEACH correlation spectrum. The indole alkaloid vincamine is used as a model compound to illustrate the application of the method. (c) 2007 John Wiley & Sons, Ltd.

Planar micro- and nano-patterning of GaN light-emitting diodes: Guidelines and limitations

NASA Astrophysics Data System (ADS)

Herrnsdorf, Johannes; Xie, Enyuan; Watson, Ian M.; Laurand, Nicolas; Dawson, Martin D.

2014-02-01

The emission area of GaN light-emitting diodes can be patterned by etch-free current aperturing methods which exploit the thin and highly resistive nature of the p-doped layer in these devices. Here, the fundamental underlying electrical and optical aspects of high-resolution current aperturing are investigated theoretically. The most critical parameter for the possible resolution is the thickness d of the p-GaN layer, but the interplay of p-GaN resistivity and electrical junction characteristics is also important. A spatial resolution of 1.59d can in principle be achieved, corresponding to about 300 nm in typical epitaxial structures. Furthermore, the emission from such a small emitter will spread by about 600 nm while propagating through the p-GaN. Both values can be reduced by reducing d.

Molten salt-mediated formation of g-C3N4-MoS2 for visible-light-driven photocatalytic hydrogen evolution

NASA Astrophysics Data System (ADS)

Li, Ni; Zhou, Jing; Sheng, Ziqiong; Xiao, Wei

2018-02-01

Construction of two-dimensional/two-dimensional (2D/2D) hybrid with well-defined composition and microstructure is a general protocol to achieve high-performance catalysts. We herein report preparation of g-C3N4-MoS2 hybrid by pyrolysis of affordable melamine and (NH4)2MoS4 in molten LiCl-NaCl-KCl at 550 °C. Molten salts are confirmed as ideal reaction media for formation of homogeneous hybrid. Characterizations suggest a strong interaction between g-C3N4 and MoS2 in the hybrid, which results in an enhanced visible-light-driven photocatalytic hydrogen generation of the hybrid with an optimal g-C3N4/MoS2 ratio. The present study highlights the merits of molten salt methods on preparation of 2D photocatalysts and provides a rational design of 2D/2D hybrid catalysts for advanced environmental and energy applications.

(13)C-(15)N correlation via unsymmetrical indirect covariance NMR: application to vinblastine.

PubMed

Martin, Gary E; Hilton, Bruce D; Blinov, Kirill A; Williams, Antony J

2007-12-01

Unsymmetrical indirect covariance processing methods allow the derivation of hyphenated 2D NMR data from the component 2D spectra, potentially circumventing the acquisition of the much lower sensitivity hyphenated 2D NMR experimental data. Calculation of HSQC-COSY and HSQC-NOESY spectra from GHSQC, COSY, and NOESY spectra, respectively, has been reported. The use of unsymmetrical indirect covariance processing has also been applied to the combination of (1)H- (13)C GHSQC and (1)H- (15)N long-range correlation data (GHMBC, IMPEACH, or CIGAR-HMBC). The application of unsymmetrical indirect covariance processing to spectra of vinblastine is now reported, specifically the algorithmic extraction of (13)C- (15)N correlations via the unsymmetrical indirect covariance processing of the combination of (1)H- (13)C GHSQC and long-range (1)H- (15)N GHMBC to produce the equivalent of a (13)C- (15)N HSQC-HMBC correlation spectrum. The elimination of artifact responses with aromatic solvent-induced shifts (ASIS) is shown in addition to a method of forecasting potential artifact responses through the indirect covariance processing of the GHSQC spectrum used in the unsymmetrical indirect covariance processing.

Production and transport of gases in the soil: from 1-D soil gas profiles towards 2- and 3-D representations of soil gas processes

NASA Astrophysics Data System (ADS)

Maier, Martin; Lang, Friederike; Schack-Kirchner, Helmer

2017-04-01

Most studies implicitly use a 1 dimensional simplification of soil processes with a dominating vertical profile, e.g in soil physical and chemical properties. In many cases, this is a useful and sufficient representation of the realty which helps to answer research questions in an efficient way. Yet, in some cases, a 2 D or 3 D analysis of the processes is necessary to avoid misinterpretation of experimental results, e.g. modeling the impact of chamber deployment time during the measurement of gas fluxes (von Fischer et al. 2009) or trenching experiments (Jassal et al. 2006). We developed a new method to determine the 2 D patterns of the soil gas diffusion coefficient DS/D0 in situ, using simultaneously several inert tracer gases. Soil gas transport was modelled inversely using the Finite Element Modeling program COMSOL. In combination with measurements of target gases such as CO2, CH4 and N2O, this allowed us for modelling the 2-D patterns of transport and production of CO2, CH4 and N2O in the soil. We observed how methane oxidation and soil respiration zones shifted within the soil profile while the gas fluxes at the surface remain rather stable during a 3 week campaign. The soil was a net sink for N2O, yet, in the subsoil local (weak) source of N2O lead to horizontal fluxes of N2O. We are testing the 3 D approach in the lab on defined substrates and objects to quantify the spatial resolution and reliability of the method. In a next step, we want to test the method in the field and study the ventilation and soil gas fluxes of an ant nest in 3D. References: von Fischer, J. C., G. Butters, P. C. Duchateau, R. J. Thelwell, and R. Siller (2009), In situ measures of methanotroph activity in upland soils: A reaction-diffusion model and field observation of water stress, J. Geophys. Res., 114, G01015, Jassal RS, Black TA (2006) Estimating heterotrophic and autotrophic soil respiration using small-area trenched plot technique: theory and practice. Agric. For. Meteorol. 140:193-202

Adaptation of the Levee Erosional Equivalence Method for the Hurricane Storm Damage Risk Reduction System (HSDRRS)

DTIC Science & Technology

2011-05-01

ER D C/ CH L TR -1 1- 3 Flood and Coastal Storm Damage Reduction R& D Program Adaptation of the Levee Erosional Equivalence Method for the...of vertical wall [-] γw Specific weight of water [kN/m3] γβ Reduction factor for influence of angle of wave attack [-] θ Landward-side levee ...stress multiplied by the flow velocity. Thus, from Equation (4) stream power has the form ERDC/CHL TR-11-3 9 S o D D dW P τ u ρ f u u ρ f u dt

Measurement of Long-Range Angular Correlation and Quadrupole Anisotropy of Pions and (Anti)Protons in Central d +Au Collisions at √{sN N }=200 GeV

NASA Astrophysics Data System (ADS)

Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'Ani, H.; Alexander, J.; Andrews, K. R.; Angerami, A.; Aoki, K.; Apadula, N.; Appelt, E.; Aramaki, Y.; Armendariz, R.; Aschenauer, E. C.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Bannier, B.; Barish, K. N.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Baublis, V.; Baumann, C.; Bazilevsky, A.; Belikov, S.; Belmont, R.; Ben-Benjamin, J.; Bennett, R.; Bhom, J. H.; Blau, D. S.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Broxmeyer, D.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Campbell, S.; Caringi, A.; Castera, P.; Chen, C.-H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Conesa Del Valle, Z.; Connors, M.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Danchev, I.; Das, K.; Datta, A.; David, G.; Dayananda, M. K.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Dharmawardane, K. V.; Dietzsch, O.; Dion, A.; Donadelli, M.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; Dutta, D.; D'Orazio, L.; Edwards, S.; Efremenko, Y. V.; Ellinghaus, F.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Fadem, B.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Gal, C.; Garishvili, I.; Glenn, A.; Gong, H.; Gong, X.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grim, G.; Grosse Perdekamp, M.; Gunji, T.; Guo, L.; Gustafsson, H.-Å.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamblen, J.; Han, R.; Hanks, J.; Harper, C.; Hashimoto, K.; Haslum, E.; Hayano, R.; He, X.; Heffner, M.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hohlmann, M.; Hollis, R. S.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hori, Y.; Hornback, D.; Huang, S.; Ichihara, T.; Ichimiya, R.; Iinuma, H.; Ikeda, Y.; Imai, K.; Inaba, M.; Iordanova, A.; Isenhower, D.; Ishihara, M.; Issah, M.; Ivanischev, D.; Iwanaga, Y.; Jacak, B. V.; Jia, J.; Jiang, X.; Jin, J.; John, D.; Johnson, B. M.; Jones, T.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kamin, J.; Kaneti, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kapustinsky, J.; Karatsu, K.; Kasai, M.; Kawall, D.; Kawashima, M.; Kazantsev, A. V.; Kempel, T.; Khanzadeev, A.; Kijima, K. M.; Kikuchi, J.; Kim, A.; Kim, B. I.; Kim, D. J.; Kim, E.-J.; Kim, Y.-J.; Kim, Y. K.; Kinney, E.; Kiss, Á.; Kistenev, E.; Kleinjan, D.; Kline, P.; Kochenda, L.; Komkov, B.; Konno, M.; Koster, J.; Kotov, D.; Král, A.; Kravitz, A.; Kunde, G. J.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, D. M.; Lee, J.; Lee, K. B.; Lee, K. S.; Lee, S. H.; Lee, S. R.; Leitch, M. J.; Leite, M. A. L.; Li, X.; Lichtenwalner, P.; Liebing, P.; Lim, S. H.; Linden Levy, L. A.; Liška, T.; Liu, H.; Liu, M. X.; Love, B.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Malik, M. D.; Manion, A.; Manko, V. I.; Mannel, E.; Mao, Y.; Masui, H.; Matathias, F.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Means, N.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Miki, K.; Milov, A.; Mitchell, J. T.; Miyachi, Y.; Mohanty, A. K.; Moon, H. J.; Morino, Y.; Morreale, A.; Morrison, D. P.; Motschwiller, S.; Moukhanova, T. V.; Murakami, T.; Murata, J.; Nagamiya, S.; Nagle, J. L.; Naglis, M.; Nagy, M. I.; Nakagawa, I.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nam, S.; Newby, J.; Nguyen, M.; Nihashi, M.; Nouicer, R.; Nyanin, A. S.; Oakley, C.; O'Brien, E.; Oda, S. X.; Ogilvie, C. A.; Oka, M.; Okada, K.; Onuki, Y.; Oskarsson, A.; Ouchida, M.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, B. H.; Park, I. H.; Park, S. K.; Park, W. J.; Pate, S. F.; Patel, L.; Pei, H.; Peng, J.-C.; Pereira, H.; Peressounko, D. Yu.; Petti, R.; Pinkenburg, C.; Pisani, R. P.; Proissl, M.; Purschke, M. L.; Qu, H.; Rak, J.; Ravinovich, I.; Read, K. F.; Rembeczki, S.; Reygers, K.; Riabov, V.; Riabov, Y.; Richardson, E.; Roach, D.; Roche, G.; Rolnick, S. D.; Rosati, M.; Rosen, C. A.; Rosendahl, S. S. E.; Ružička, P.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sakashita, K.; Samsonov, V.; Sano, S.; Sarsour, M.; Sato, T.; Savastio, M.; Sawada, S.; Sedgwick, K.; Seele, J.; Seidl, R.; Seto, R.; Sharma, D.; Shein, I.; Shibata, T.-A.; Shigaki, K.; Shim, H. H.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Silvestre, C.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Slunečka, M.; Sodre, T.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Sourikova, I. V.; Stankus, P. W.; Stenlund, E.; Stoll, S. P.; Sugitate, T.; Sukhanov, A.; Sun, J.; Sziklai, J.; Takagui, E. M.; Takahara, A.; Taketani, A.; Tanabe, R.; Tanaka, Y.; Taneja, S.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tennant, E.; Themann, H.; Thomas, D.; Thomas, T. L.; Togawa, M.; Toia, A.; Tomášek, L.; Tomášek, M.; Torii, H.; Towell, R. S.; Tserruya, I.; Tsuchimoto, Y.; Utsunomiya, K.; Vale, C.; Valle, H.; van Hecke, H. W.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Virius, M.; Vossen, A.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Watanabe, Y. S.; Wei, F.; Wei, R.; Wessels, J.; White, S. N.; Winter, D.; Woody, C. L.; Wright, R. M.; Wysocki, M.; Yamaguchi, Y. L.; Yamaura, K.; Yang, R.; Yanovich, A.; Ying, J.; Yokkaichi, S.; Yoo, J. S.; You, Z.; Young, G. R.; Younus, I.; Yushmanov, I. E.; Zajc, W. A.; Zelenski, A.; Zhou, S.; Phenix Collaboration

2015-05-01

We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d +Au and minimum bias p +p collisions at √{sN N }=200 GeV . The charged hadron is measured at midrapidity |η |<0.35 , and the energy is measured at large rapidity (-3.7 <η <-3.1 , Au-going direction). An enhanced near-side angular correlation across |Δ η |>2.75 is observed in d +Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v2 for inclusive charged hadrons at midrapidity up to pT=4.5 GeV /c . We also present the measurement of v2 for identified π± and (anti)protons in central d +Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p +Pb at √{sN N }=5.02 TeV . The magnitude of the mass ordering in d +Au is found to be smaller than that in p +Pb collisions, which may indicate smaller radial flow in lower energy d +Au collisions.

The role of sequence context, nucleotide pool balance and stress in 2′-deoxynucleotide misincorporation in viral, bacterial and mammalian RNA

PubMed Central

Wang, Jin; Dong, Hongping; Chionh, Yok Hian; McBee, Megan E.; Sirirungruang, Sasilada; Cunningham, Richard P.; Shi, Pei-Yong; Dedon, Peter C.

2016-01-01

The misincorporation of 2′-deoxyribonucleotides (dNs) into RNA has important implications for the function of non-coding RNAs, the translational fidelity of coding RNAs and the mutagenic evolution of viral RNA genomes. However, quantitative appreciation for the degree to which dN misincorporation occurs is limited by the lack of analytical tools. Here, we report a method to hydrolyze RNA to release 2′-deoxyribonucleotide-ribonucleotide pairs (dNrN) that are then quantified by chromatography-coupled mass spectrometry (LC-MS). Using this platform, we found misincorporated dNs occurring at 1 per 103 to 105 ribonucleotide (nt) in mRNA, rRNAs and tRNA in human cells, Escherichia coli, Saccharomyces cerevisiae and, most abundantly, in the RNA genome of dengue virus. The frequency of dNs varied widely among organisms and sequence contexts, and partly reflected the in vitro discrimination efficiencies of different RNA polymerases against 2′-deoxyribonucleoside 5′-triphosphates (dNTPs). Further, we demonstrate a strong link between dN frequencies in RNA and the balance of dNTPs and ribonucleoside 5′-triphosphates (rNTPs) in the cellular pool, with significant stress-induced variation of dN incorporation. Potential implications of dNs in RNA are discussed, including the possibilities of dN incorporation in RNA as a contributing factor in viral evolution and human disease, and as a host immune defense mechanism against viral infections. PMID:27365049

ROOFN3D: Deep Learning Training Data for 3d Building Reconstruction

NASA Astrophysics Data System (ADS)

Wichmann, A.; Agoub, A.; Kada, M.

2018-05-01

Machine learning methods have gained in importance through the latest development of artificial intelligence and computer hardware. Particularly approaches based on deep learning have shown that they are able to provide state-of-the-art results for various tasks. However, the direct application of deep learning methods to improve the results of 3D building reconstruction is often not possible due, for example, to the lack of suitable training data. To address this issue, we present RoofN3D which provides a new 3D point cloud training dataset that can be used to train machine learning models for different tasks in the context of 3D building reconstruction. It can be used, among others, to train semantic segmentation networks or to learn the structure of buildings and the geometric model construction. Further details about RoofN3D and the developed data preparation framework, which enables the automatic derivation of training data, are described in this paper. Furthermore, we provide an overview of other available 3D point cloud training data and approaches from current literature in which solutions for the application of deep learning to unstructured and not gridded 3D point cloud data are presented.

Value of 3D MR lumbosacral radiculography in the diagnosis of symptomatic chemical radiculitis.

PubMed

Byun, W M; Ahn, S H; Ahn, M-W

2012-03-01

Radiologic methods for the diagnosis of chemical radiculitis associated with anular tears in the lumbar spine have been rare. Provocative diskography is one of the methods for diagnosing diskogenic chemical radiculitis but is invasive. A reliable imaging method for replacing provocative diskography and diagnosing chemical radiculitis is required. Our aim was to investigate the value of 3D MR radiculography depicted by rendering imaging in the diagnosis of symptomatic chemical radiculopathy associated with anular tears. The study population consisted of 17 patients (age range, 32-88 years) with unilateral radiculopathy. Symptomatic chemical radiculopathy was confirmed with provocative CT diskography and/or provocative selective nerve root block for agreement of sides and levels. Through adhering to the principles of selective excitation (Proset imaging), we acquired 3D coronal FFE sequences with selective water excitation. Morphologic changes in the ipsilateral symptomatic nerve root caused by chemical radiculopathy were compared with those in the contralateral nerve root on 3D MR lumbosacral radiculography. Pain reproduction at the contrast-leak level during diskography (n = 4) and selective nerve root injection (n = 13) showed concordant pain in all patients. All patients with symptomatic chemical radiculopathy showed nerve root swelling in both ipsilateral levels and sides on 3D MR radiculography. The most common nerve root affected by the chemical radiculopathy was the L5 nerve root (n = 13), while the most common segment exhibiting nerve root swelling was the exit nerve root (n = 16). All patients with radicular leg pain caused by chemical radiculopathy showed nerve root swelling on 3D MR radiculography. We believe that in cases without mechanical nerve root compression caused by disk herniation or stenosis in the lumbar spine, nerve root swelling on 3D MR radiculography in patients with radiculopathy associated with an anular tear may be relevant in the diagnosis of symptomatic chemical radiculopathy.

Comparison of fractionation methods for nitrogen and starch in maize and grass silages.

PubMed

Ali, M; de Jonge, L H; Cone, J W; van Duinkerken, G; Blok, M C; Bruinenberg, M H; Hendriks, W H

2016-06-01

In in situ nylon bag technique, many feed evaluation systems use a washing machine method (WMM) to determine the washout (W) fraction and to wash the rumen incubated nylon bags. As this method has some disadvantages, an alternate modified method (MM) was recently introduced. The aim of this study was to determine and compare the W and non-washout (D+U) fractions of nitrogen (N) and/or starch of maize and grass silages, using the WMM and the MM. Ninety-nine maize silage and 99 grass silage samples were selected with a broad range in chemical composition. The results showed a large range in the W, soluble (S) and D+U fractions of N of maize and grass silages and the W, insoluble washout (W-S) and D+U fractions of starch of maize silages, determined by both methods, due to variation in their chemical composition. The values for N fractions of maize and grass silages obtained with both methods were found different (p < 0.001). Large differences (p < 0.001) were found in the D+U fraction of starch of maize silages which might be due to different methodological approaches, such as different rinsing procedures (washing vs. shaking), duration of rinsing (40 min vs. 60 min) and different solvents (water vs. buffer solution). The large differences (p < 0.001) in the W-S and D+U fractions of starch determined with both methods can led to different predicted values for the effective rumen starch degradability. In conclusion, the MM with one recommended shaking procedure, performed under identical and controlled experimental conditions, can give more reliable results compared to the WMM, using different washing programs and procedures. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Development of an HPLC Method with an ODS Column to Determine Low Levels of Aspartame Diastereomers in Aspartame

PubMed Central

Ohtsuki, Takashi; Nakamura, Ryoichiro; Kubo, Satoru; Otabe, Akira; Oobayashi, Yoko; Suzuki, Shoko; Yoshida, Mika; Yoshida, Mitsuya; Tatebe, Chiye; Sato, Kyoko; Akiyama, Hiroshi

2016-01-01

α-L-Aspartyl-D-phenylalanine methyl ester (L, D-APM) and α-D-aspartyl-L-phenylalanine methyl ester (D, L-APM) are diastereomers of aspartame (N-L-α-Aspartyl-L-phenylalanine-1-methyl ester, L, L-APM). The Joint FAO/WHO Expert Committee on Food Additives has set 0.04 wt% as the maximum permitted level of the sum of L, D-APM and D, L-APM in commercially available L, L-APM. In this study, we developed and validated a simple high-performance liquid chromatography (HPLC) method using an ODS column to determine L, D-APM and D, L-APM in L, L-APM. The limits of detection and quantification, respectively, of L, D-APM and D, L-APM were found to be 0.0012 wt% and 0.004 wt%. This method gave excellent accuracy, repeatability, and reproducibility in a recovery test performed on five different days. Moreover, the method was successfully applied to the determination of these diastereomers in commercial L, L-APM samples. Thus, the developed method is a simple, useful, and practical tool for determining L, D-APM and D, L-APM levels in L, L-APM. PMID:27015640

Development of an HPLC Method with an ODS Column to Determine Low Levels of Aspartame Diastereomers in Aspartame.

PubMed

Ohtsuki, Takashi; Nakamura, Ryoichiro; Kubo, Satoru; Otabe, Akira; Oobayashi, Yoko; Suzuki, Shoko; Yoshida, Mika; Yoshida, Mitsuya; Tatebe, Chiye; Sato, Kyoko; Akiyama, Hiroshi

2016-01-01

α-L-Aspartyl-D-phenylalanine methyl ester (L, D-APM) and α-D-aspartyl-L-phenylalanine methyl ester (D, L-APM) are diastereomers of aspartame (N-L-α-Aspartyl-L-phenylalanine-1-methyl ester, L, L-APM). The Joint FAO/WHO Expert Committee on Food Additives has set 0.04 wt% as the maximum permitted level of the sum of L, D-APM and D, L-APM in commercially available L, L-APM. In this study, we developed and validated a simple high-performance liquid chromatography (HPLC) method using an ODS column to determine L, D-APM and D, L-APM in L, L-APM. The limits of detection and quantification, respectively, of L, D-APM and D, L-APM were found to be 0.0012 wt% and 0.004 wt%. This method gave excellent accuracy, repeatability, and reproducibility in a recovery test performed on five different days. Moreover, the method was successfully applied to the determination of these diastereomers in commercial L, L-APM samples. Thus, the developed method is a simple, useful, and practical tool for determining L, D-APM and D, L-APM levels in L, L-APM.

Exome sequencing for simultaneous mutation screening in children with hemophagocytic lymphohistiocytosis.

PubMed

Mukda, Ekchol; Trachoo, Objoon; Pasomsub, Ekawat; Tiyasirichokchai, Rawiphorn; Iemwimangsa, Nareenart; Sosothikul, Darintr; Chantratita, Wasun; Pakakasama, Samart

2017-08-01

In the present study, we used exome sequencing to analyze PRF1, UNC13D, STX11, and STXBP2, as well as genes associated with primary immunodeficiency disease (RAB27A, LYST, AP3B1, SH2D1A, ITK, CD27, XIAP, and MAGT1) in Thai children with hemophagocytic lymphohistiocytosis (HLH). We performed mutation analysis of HLH-associated genes in 25 Thai children using an exome sequencing method. Genetic variations found within these target genes were compared to exome sequencing data from 133 healthy individuals. Variants identified with minor allele frequencies <5% and novel mutations were confirmed using Sanger sequencing. Exome sequencing data revealed 101 non-synonymous single nucleotide polymorphisms (SNPs) in all subjects. These SNPs were classified as pathogenic (n = 1), likely pathogenic (n = 16), variant of unknown significance (n = 12), or benign variant (n = 72). Homozygous, compound heterozygous, and double-gene heterozygous variants, involving mutations in PRF1 (n = 3), UNC13D (n = 2), STXBP2 (n = 3), LYST (n = 3), XIAP (n = 2), AP3B1 (n = 1), RAB27A (n = 1), and MAGT1 (n = 1), were demonstrated in 12 patients. Novel mutations were found in most patients in this study. In conclusion, exome sequencing demonstrated the ability to identify rare genetic variants in HLH patients. This method is useful in the detection of mutations in multi-gene associated diseases.

A method for designing configurations of nested monitoring wells near landfills

NASA Astrophysics Data System (ADS)

Hudak, Paul F.

A method was devised for designing configurations of monitoring wells, consisting of vertically nested intakes in boreholes. The network-design method involves analyzing a subset of potential contaminant plumes emerging from the downgradient margin of a landfill. Plume widths are evaluated along selected equipotential lines and compared to the lengths of those lines. The method was applied to a 32-ha solid-waste landfill in Tarrant County, Texas, USA. Sixtynine potential source nodes were considered. A 15-borehole network devised by the method registered 93 detections in total, detecting all 69 model-generated plumes by at least one borehole. Based on an enumeration procedure, a minimum of 10 boreholes was needed to detect all of the model-generated plumes. However, the less conservative 10-borehole network had little capability for backup detection. An existing monitoring network of seven downgradient wells detected only 38 model-generated plumes. Results of this study illustrate a practical need for structured approaches to designing detection-based groundwater-monitoring configurations. Résumé Une méthode a été développée pour fournir les caractéristiques de puits de surveillance, avec des points de prélèvements superposés en forage. La méthode de réalisation du réseau s'appuie sur l'analyse d'un ensemble de panaches de pollution potentiels provenant du bord en aval d'une décharge. Les largeurs de panache sont estimées le long d'isopièzes sélectionnées et sont comparées à leur longueur. Cette méthode a été appliquée à une décharge de déchets solides couvrant 32ha, dans le canton de Tarrant (Texas, Etats-Unis). 69 noeuds de source potentielle de pollution ont été pris en compte. Un réseau de 15 forages, défini par la méthode, a enregistré au total 93 alarmes, détectant les 69 panaches simulés dans au moins un forage. Une procédure de dénombrement précise qu'un minimum de 10 forages est nécessaire pour détecter tous les panaches simulés par le modèle. Cependant, le réseau minimal de 10 forages offre une faible aptitude de détection. Un réseau existant de contrôle de 7 puits situés en aval ne détectent que 38 panaches simulés par le modèle. Les résultats de cette étude illustrent la nécessité pratique d'approches structurées pour la définition des caractéristiques de surveillance d'une nappe basée sur la détection. Resumen Se ha puesto en marcha un método para diseñar la configuración de los pozos de observación, que consiste en estudiar las captaciones en tramos anidados verticalmente. El método de diseño de redes incluye el análisis de un subconjunto de penachos de contaminación que emergen potencialmente aguas abajo de un vertedero. Se evalúa la anchura de los penachos a lo largo de líneas equipotenciales seleccionadas y se compara con la longitud de estas líneas. El método se aplicó a un vertedero de sustancias sólidas con una extensión de 32 hectáreas en Tarrant County, Texas, EEUU. Se consideraron 69 fuentes de contaminación potencial. Una red de 15 sondeos, seleccionada mediante el nuevo método, registró un total de 93 detecciones, consiguiendo detectar el total de los 69 penachos generados en por lo menos un pozo. Basándose en un procedimiento de enumeración, se vio se requería un mínimo de 10 sondeos para registrar la totalidad de los penachos. Sin embargo, esta red de 10 sondeos se considera muy poco conservativa, ya que tenía una capacidad limitada para detectar los puntos de partida. Una red ya existente, formada por siete pozos aguas abajo de la zona de vertido, detectó sólo 38 de los penachos. Los resultados de este estudio ilustran la necesidad práctica de metodologías estructuradas para diseñar las configuraciones de redes de observación.

Membrane current of retinal rods of Caudiverbera caudiverbera (Amphibia: Leptodactylidae): dark noise, spectral and absolute light sensitivity.

PubMed

Palma, F; Roncagliolo, P; Bacigalupo, J; Palacios, A G

2001-01-01

We investigated the photocurrents from isolated rods of the South American anuran, Caudiverbera caudiverbera. Rod outer segments were on average 66.4 +/- 11.2 microm (mean +/- S.D., n = 104) in length and 6.6 +/- 0.9 microm (mean +/- S.D.) in diameter: 40 +/- 22 photoisomerizations (mean +/- S.D., range 10-99, n = 16) were required for eliciting a half-saturating photocurrent response. The time-to-peak was 911 +/- 217 ms (mean +/- S.D., n = 14, 20 degrees C) in the linear range of the response and the integration time of the current response was 1744 +/- 451 ms (mean +/- S.D., n = 14). The time-to-peak appears to be slower and the integration time shorter in Caudiverbera than in Ambystoma tigrinum, Rana pipiens or Xenopus laevis rods under similar experimental conditions. The a-band of rod spectral sensitivity has a lambda(max) at 520 +/- 2.1 nm (mean +/- S.D., range 516-525 nm, n = 24) and the bandwidth fits a porphyropsin visual pigment. The single-event response amplitude ranges from 0.31-0.51 pA, depending on the calculation method. The intrinsic dark current (variance at dark minus variance under bright light) was 0.045 +/- 0.040 pA2 (mean +/- S.D., n = 24). Our results support the presence of a dark-noise component below 1 Hz, with kinetics similar to the single-photon evoked response and a rate of 0.006 events s(-1) (n = 9).

Design of synthetic soil images using the Truncated Multifractal method

NASA Astrophysics Data System (ADS)

Sotoca, Juan J. Martin; Saa-Requejo, Antonio; López de Herrera, Juan; Grau, Juan B.

2017-04-01

The use of synthetic images in soils is an increasingly used resource when comparing different segmentation methods. This type of images can simulate features of the real soil images. We can find examples of 2D and 3D synthetic soil images in the studies by Zhang (2001), Schlüter et al. (2010) and Wang et al. (2011). The aim of this presentation is to show an improved version of the Truncated Multifractal method (TMM) which was initially introduced by Martín-Sotoca et al. (2016a, 2016b). The TMM is able to construct a 3D synthetic soil image that is composed of a known air-filled pore space and a background space, which includes, as a novelty, a pebble space. The pebble space simulates the pebbles or granules of high intensity that typically appear in computed tomography (CT) soil images. The TMM can simulate the two main characteristics of the CT soil images: the scaling nature of the pore space and the low contrast at the solid/pore interface with non-bimodal greyscale value histograms. In this presentation we introduce some new components which improve the similitude between real and synthetic CT soil images. REFERENCES Martín-Sotoca, J.J., Saa-Requejo, A., Grau, J.B. and Tarquis, A.M. (2016a). New segmentation method based on fractal properties using singularity maps. Geoderma, doi: 10.1016/j.geoderma.2016.09.005 Martín-Sotoca, J.J., Saa-Requejo, A., Grau, J.B., Tarquis, A.M. (2016b). Local 3D segmentation of soil pore space based on fractal properties using singularity maps. Geoderma, doi: 10.1016/j.geoderma.2016.11.029 Schlüter, S., Weller, U., Vogel, H.J., (2010). Thresholding of X-ray microtomography images of soil using gradient masks. Comput. Geosci. 36, 1246-1251 Wang, W., Kravchenko, A.N., Smucker, A.J.M., Rivers, M.L. (2011). Comparison of image segmentation methods in simulated 2D and 3D microtomographic images of soil aggregates. Geoderma, 162, 231-241 Zhang, Y.J. (2001). A review of recent evaluation methods for image segmentation: International symposium on signal processing and its applications. Kuala Lumpur, Malaysia, 13-16, pp. 148-151

Correlation of Resistivity Value with Geotechnical N-Value of Sedimentary Area in Nusajaya, Johor, Malaysia

NASA Astrophysics Data System (ADS)

Akip Tan, S. N. Mohd; Edy Tonnizam, M.; Saad, R.; Dan, M. F. Md; Nordiana, M. M.; Hazreek, Z. A. M.; Madun, A.

2018-04-01

Electrical resistivity survey and the geotechnical SPT blow counts (N-value) were carried out simultaneously on the tropically weathered sedimentary rock mass for an excavation project at Nusajaya, Johor, Malaysia. This study aims to determine subsurface profile by using 2D-resistivity methods and correlate with N-value derived from boring works. Four boreholes were investigated in five survey lines that revealed the site is underlain by moderately to completely weathered sandstone, clay, silt and shale. Data analysis from 2D-resistivity image shows that zones with high resistivity value generally have high N-value, and vice versa. Five zones have inversed the proportional relation between N-value and resistivity Ωm value due to different types of soil lithology. It indicates that 2D-resistivity is significance to detect bodies of anomalous materials or estimating the depth of bedrock. As a conclusion, the integration of geophysical and geotechnical analysis provides a promise approach to understand some relationship concerning the subsurface subsurface ground through the combination of 2D-resistivity and N-value.

Evaluation of Systems Engineering Methods, Processes and Tools on Department of Defense and Intelligence Community Programs - Phase 2

DTIC Science & Technology

2009-12-15

O 0 0 1, T O 0 0 2...ber: H 9 8 230 -0 8 -D -0 171 D O 0 0 1, T O 0 0 2. R T 0 0 9 4 7 C O N TIN UO US IN TEG RA TIO N Theme Elements...D O 0 0 1, T O 0 0 2. R T 0 0 9 51 RA PID PRO TO TYPIN G Theme Elements Time-boxed development process Delivery

Instructor/Operator Display Evaluation Methods

DTIC Science & Technology

1981-03-01

14 IV. Experimental Desln.n ........ .................... ... 16 V. Procedure ............................................. 18 VI, Results...plies and thus the length of time during which the information must be retained. 16 ...... Nu -n4- (0 4-)~ R IW~~ IH I CDWC * I t I’ CI I~ _ _ I _ _17...standard deviation (S.D.) of 3.0 years. Total flight hours averaged 2248 (S.D. = 858). Current equipment for 16 pilots was the C-130 in which they

Ultrahigh-performance liquid chromatography-ion trap mass spectrometry characterization of the steroidal saponins of Dioscorea panthaica Prain et Burkill and its application for accelerating the isolation and structural elucidation of steroidal saponins.

PubMed

Wang, Weihao; Zhao, Ye; Jing, Wenguang; Zhang, Jun; Xiao, Hui; Zha, Qin; Liu, An

2015-03-01

Dioscorea panthaica is a traditional Chinese medicinal herb used in the treatment of various physiological conditions, including cardiovascular disease, gastropathy and hypertension. Steroidal saponins (SS) are the main active ingredients of this herb and have effects on myocardial ischemia and cancer. The phytochemical evaluation of SS is both time-consuming and laborious, and the isolation and structural determination steps can be especially demanding. For this reason, the development of new methods to accelerate the processes involved in the identification, isolation and structural elucidation of SS is highly desirable. In this study, a new ultrahigh performance liquid chromatography-ion trap mass spectrometry (UHPLC-IT/MS(n)) method has been developed for the identification of the SS in D. panthaica Prain et Burkill. Notably, the current method can distinguish between spirostanol and furostanol-type compounds based on the fragmentation patterns observed by electrospray ionization-ion trap mass spectrometry (ESI-IT/MS(n)) analysis. UHPLC-IT/MS(n) was used to conduct a detailed investigation of the number, structural class and order of the sugar moieties in the sugar chains of the SS present in D. panthaica. The established fragmentation features were used to analyze the compounds found in the 65% ethanol fraction of the water extracts of D. panthaica. Twenty-three SS were identified, including 11 potential new compounds and six groups of isomers. Two of these newly identified SS were selected as representative examples, and their chemical structures were confirmed by (1)H and (13)C NMR analyses. This newly developed UHPLC-IT/MS(n) method therefore allowed for the efficient identification, isolation and structural determination of the SS in D. panthaica. Copyright © 2015 Elsevier Inc. All rights reserved.

Wavelet bases on the L-shaped domain

NASA Astrophysics Data System (ADS)

Jouini, Abdellatif; Lemarié-Rieusset, Pierre Gilles

2013-07-01

We present in this paper two elementary constructions of multiresolution analyses on the L-shaped domain D. In the first one, we shall describe a direct method to define an orthonormal multiresolution analysis. In the second one, we use the decomposition method for constructing a biorthogonal multiresolution analysis. These analyses are adapted for the study of the Sobolev spaces Hs(D)(s∈N).

Convergence on the Prediction of Ice Particle Mass and Projected Area in Ice Clouds

NASA Astrophysics Data System (ADS)

Mitchell, D. L.

2013-12-01

Ice particle mass- and area-dimensional power law (henceforth m-D and A-D) relationships are building-blocks for formulating microphysical processes and optical properties in cloud and climate models, and they are critical for ice cloud remote sensing algorithms, affecting the retrieval accuracy. They can be estimated by (1) directly measuring the sizes, masses and areas of individual ice particles at ground-level and (2) using aircraft probes to simultaneously measure the ice water content (IWC) and ice particle size distribution. A third indirect method is to use observations from method 1 to develop an m-A relationship representing mean conditions in ice clouds. Owing to a tighter correlation (relative to m-D data), this m-A relationship can be used to estimate m from aircraft probe measurements of A. This has the advantage of estimating m at small sizes, down to 10 μm using the 2D-Sterio probe. In this way, 2D-S measurements of maximum dimension D can be related to corresponding estimates of m to develop ice cloud type and temperature dependent m-D expressions. However, these expressions are no longer linear in log-log space, but are slowly varying curves covering most of the size range of natural ice particles. This work compares all three of the above methods and demonstrates close agreement between them. Regarding (1), 4869 ice particles and corresponding melted hemispheres were measured during a field campaign to obtain D and m. Selecting only those unrimed habits that formed between -20°C and -40°C, the mean mass values for selected size intervals are within 35% of the corresponding masses predicted by the Method 3 curve based on a similar temperature range. Moreover, the most recent m-D expression based on Method 2 differs by no more than 50% with the m-D curve from Method 3. Method 3 appears to be the most accurate over the observed ice particle size range (10-4000 μm). An m-D/A-D scheme was developed by which self-consistent m-D and A-D power laws are extracted from Method 3 for a given ice particle number concentration N and IWC, appropriate for the relevant size range inferred from N and IWC. The resulting m-D/A-D power laws are based on the same data set comprised of 24 flights in ice clouds during a 6-month field campaign. Standard deviations for these power law constants are determined, which are much needed for cloud property remote sensing algorithms. Comparison of Method 3 (curve fit) with Method 1 (red std. deviations from measurements of ice particles found in cirrus clouds) and Method 2 (Cotton et al. and Heymsfield et al.).

Effect of saturated fatty acid-rich dietary vegetable oils on lipid profile, antioxidant enzymes and glucose tolerance in diabetic rats

PubMed Central

Kochikuzhyil, Benson Mathai; Devi, Kshama; Fattepur, Santosh Raghunandan

2010-01-01

Objective: To study the effect of saturated fatty acid (SFA)-rich dietary vegetable oils on the lipid profile, endogenous antioxidant enzymes and glucose tolerance in type 2 diabetic rats. Materials and Methods: Type 2 diabetes was induced by administering streptozotocin (90 mg/kg, i.p.) in neonatal rats. Twenty-eight-day-old normal (N) and diabetic (D) male Wistar rats were fed for 45 days with a fat-enriched special diet (10%) prepared with coconut oil (CO) – lauric acid-rich SFA, palm oil (PO) – palmitic acid-rich SFA and groundnut oil (GNO) – control (N and D). Lipid profile, endogenous antioxidant enzymes and oral glucose tolerance tests were monitored. Results: D rats fed with CO (D + CO) exhibited a significant decrease in the total cholesterol and non-high-density lipoprotein cholesterol. Besides, they also showed a trend toward improving antioxidant enzymes and glucose tolerance as compared to the D + GNO group, whereas D + PO treatment aggravated the dyslipidemic condition while causing a significant decrease in the superoxide dismutase levels when compared to N rats fed with GNO (N + GNO). D + PO treatment also impaired the glucose tolerance when compared to N + GNO and D + GNO. Conclusion: The type of FA in the dietary oil determines its deleterious or beneficial effects. Lauric acid present in CO may protect against diabetes-induced dyslipidemia. PMID:20871763

Graphite-like carbon nitride coupled with tiny Bi2S3 nanoparticles as 2D/0D heterojunction with enhanced photocatalytic activity

NASA Astrophysics Data System (ADS)

Zhu, Chengzhang; Gong, Tingting; Xian, Qiming; Xie, Jimin

2018-06-01

Novel well-dispersed tiny Bi2S3 nanoparticles (NPs) with an average sizes of approximately 16.2 nm were used to decorate layered g-C3N4 nanosheets (NSs), with the purpose of constructing highly efficient 0D/2D heterojunction photocatalyst by a simple hydrothermal method in one step. The fabricated Bi2S3/g-C3N4 heterostructures exhibited superior visible-light-driven photocatalytic activity toward methyl orange (MO) degradation in contrast to that of individual Bi2S3 and g-C3N4, which could be mainly ascribed to the synergistic effect of the tiny size effect of 0D Bi2S3 NPs and 2D g-C3N4 NSs, the matched energy level positions, and the abundant coupling heterointerfaces between two moieties. More importantly, the photodegradation of methylene blue (MB), rhodamine B (RhB) and colorless tetracycline (TC), ciprofloxacin (CIP) further revealed the broad-spectrum photodegradation capacities of the heterojunction materials. The possible photoinduced charge transfer and pollutant degradation process over Bi2S3/g-C3N4 heterojunctions under visible-light irradiation were proposed. This work may provide a platform for constructing new visible light 0D/2D intimate contact heterostructures with stable and efficient photocatalytic performance.

21 CFR 177.1610 - Polyethylene, chlorinated.

Code of Federal Regulations, 2010 CFR

2010-04-01

... produced by the direct chlorination of polyethylene conforming to the density, maximum n-hexane extractable... extractable fraction in n-hexane at 50 °C, as determined by the method described in § 177.1520(d)(3)(ii). (b...

21 CFR 177.1610 - Polyethylene, chlorinated.

Code of Federal Regulations, 2011 CFR

2011-04-01

... produced by the direct chlorination of polyethylene conforming to the density, maximum n-hexane extractable... extractable fraction in n-hexane at 50 °C, as determined by the method described in § 177.1520(d)(3)(ii). (b...

21 CFR 177.1610 - Polyethylene, chlorinated.

Code of Federal Regulations, 2012 CFR

2012-04-01

... produced by the direct chlorination of polyethylene conforming to the density, maximum n-hexane extractable... extractable fraction in n-hexane at 50 °C, as determined by the method described in § 177.1520(d)(3)(ii). (b...

21 CFR 177.1610 - Polyethylene, chlorinated.

Code of Federal Regulations, 2013 CFR

2013-04-01

... produced by the direct chlorination of polyethylene conforming to the density, maximum n-hexane extractable... extractable fraction in n-hexane at 50 °C, as determined by the method described in § 177.1520(d)(3)(ii). (b...

Theoretical and experimental studies of the current–voltage and capacitance–voltage of HEMT structures and field-effect transistors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tarasova, E. A.; Obolenskaya, E. S., E-mail: obolensk@rf.unn.ru; Hananova, A. V.

The sensitivity of classical n{sup +}/n{sup –} GaAs and AlGaN/GaN structures with a 2D electron gas (HEMT) and field-effect transistors based on these structures to γ-neutron exposure is studied. The levels of their radiation hardness were determined. A method for experimental study of the structures on the basis of a differential analysis of their current–voltage characteristics is developed. This method makes it possible to determine the structure of the layers in which radiation-induced defects accumulate. A procedure taking into account changes in the plate area of the experimentally measured barrier-contact capacitance associated with the emergence of clusters of radiation-induced defectsmore » that form dielectric inclusions in the 2D-electron-gas layer is presented for the first time.« less

Study of the plastic zone around the ligament of thin sheet D.E.N.T specimen subjected to tensile

NASA Astrophysics Data System (ADS)

Djebali, S.; Larbi, S.; Bilek, A.

2015-03-01

One of the assumptions of Cotterell and Reddel's method of the essential work of fracture determination is the existence of a fracture process zone surrounded by an outer plastic zone extending to the whole ligament before crack initiation. To verify this hypothesis we developed a method based on micro hardness. The hardness values measured in the domain surrounding the tensile fracture area of ST-37-2 steel sheet D.E.N.T specimens confirm the existence of the two plastic zones. The extension of the plastic deformations to the whole ligament before the crack initiation and the circular shape of the outer plastic zone are revealed by the brittle coating method.

Improvement in Social Competence Using a Randomized Trial of a Theatre Intervention for Children with Autism Spectrum Disorder.

PubMed

Corbett, Blythe A; Key, Alexandra P; Qualls, Lydia; Fecteau, Stephanie; Newsom, Cassandra; Coke, Catherine; Yoder, Paul

2016-02-01

The efficacy of a peer-mediated, theatre-based intervention on social competence in participants with autism spectrum disorder (ASD) was tested. Thirty 8-to-14 year-olds with ASD were randomly assigned to the treatment (n = 17) or a wait-list control (n = 13) group. Immediately after treatment, group effects were seen on social ability, (d = .77), communication symptoms (d = -.86), group play with toys in the company of peers (d = .77), immediate memory of faces as measured by neuropsychological (d = .75) and ERP methods (d = .93), delayed memory for faces (d = .98), and theory of mind (d = .99). At the 2 month follow-up period, group effects were detected on communication symptoms (d = .82). The results of this pilot clinical trial provide initial support for the efficacy of the theatre-based intervention.

Comparison of marine sampling methods for organic contaminants: Passive samplers, water extractions, and live oyster deployment.

PubMed

Raub, Kristin B; Vlahos, Penny; Whitney, Michael

2015-08-01

Laboratory and field trials evaluated the efficacy of three methods of detecting aquatic pesticide concentrations. Currently used pesticides: atrazine, metolachlor, and diazinon and legacy pesticide dieldrin were targeted. Pesticides were extracted using solid-phase extraction (SPE) of water samples, titanium plate passive samplers coated in ethylene vinyl acetate (EVA) and eastern oysters (Crassostrea viginica) as biosamplers. A laboratory study assessed the extraction efficiencies and precision of each method. Passive samplers yielded the highest precision of the three methods (RSD: 3-14% EVA plates; 19-60% oysters; and 25-56% water samples). Equilibrium partition coefficients were derived. A significant relationship was found between the concentration in oyster tissue and the ambient aquatic concentration. In the field (Housatonic River, CT (U.S.)) water sampling (n = 5) detected atrazine at 1.61-7.31 μg L(-1), oyster sampling (n = 2×15) detected dieldrin at n.d.-0.096 μg L(-1) SW and the passive samplers (n = 5×3) detected atrazine at 0.97-3.78 μg L(-1) SW and dieldrin at n.d.-0.68 μg L(-1) SW. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impacts of oxidants in atomic layer deposition method on Al2O3/GaN interface properties

NASA Astrophysics Data System (ADS)

Taoka, Noriyuki; Kubo, Toshiharu; Yamada, Toshikazu; Egawa, Takashi; Shimizu, Mitsuaki

2018-01-01

The electrical interface properties of GaN metal-oxide-semiconductor (MOS) capacitors with an Al2O3 gate insulator formed by atomic layer deposition method using three kinds of oxidants were investigated by the capacitance-voltage technique, Terman method, and conductance method. We found that O3 and the alternate supply of H2O and O3 (AS-HO) are effective for reducing the interface trap density (D it) at the energy range of 0.15 to 0.30 eV taking from the conduction band minimum. On the other hand, we found that surface potential fluctuation (σs) induced by interface charges for the AS-HO oxidant is much larger than that for a Si MOS capacitor with a SiO2 layer formed by chemical vapor deposition despite the small D it values for the AS-HO oxidant compared with the Si MOS capacitor. This means that the total charged center density including the fixed charge density, charged slow trap density, and charged interface trap density for the GaN MOS capacitor is higher than that for the Si MOS capacitor. Therefore, σs has to be reduced to improve the performances and reliability of GaN devices with the Al2O3/GaN interfaces.

A barrier-free atomic radical-molecule reaction: N (2D) NO2 (2A1) mechanistic study

NASA Astrophysics Data System (ADS)

Zuo, Ming-Hui; Liu, Hui-Ling; Huang, Xu-Ri; Zhan, Jin-Hui; Sun, Chia-Chung

The reaction of N (2D) radical with NO2 molecule has been studied theoretically using density functional theory and ab initio quantum chemistry method. Singlet electronic state [N2O2] potential energy surfaces (PES) are calculated at the CCSD(T)/aug-cc-pVDZ//B3LYP/6-311+G(d) + ZPE and G3B3 levels of theory. All the involved transition states for generation of (2NO) and (O2 + N2) lie much lower than the reactants. Thus, the novel reaction N + NO2 can proceed effectively even at low temperatures and it is expected to play a role in both combustion and interstellar processes. On the basis of the analysis of the kinetics of all pathways through which the reactions proceed, we expect that the competitive power of reaction pathways may vary with experimental conditions for the title reaction.

Fully Implicit, Nonlinear 3D Extended Magnetohydrodynamics

NASA Astrophysics Data System (ADS)

Chacon, Luis; Knoll, Dana

2003-10-01

Extended magnetohydrodynamics (XMHD) includes nonideal effects such as nonlinear, anisotropic transport and two-fluid (Hall) effects. XMHD supports multiple, separate time scales that make explicit time differencing approaches extremely inefficient. While a fully implicit implementation promises efficiency without sacrificing numerical accuracy,(D. A. Knoll et al., phJ. Comput. Phys.) 185 (2), 583-611 (2003) the nonlinear nature of the XMHD system and the numerical stiffness associated with the fast waves make this endeavor difficult. Newton-Krylov methods are, however, ideally suited for such a task. These synergistically combine Newton's method for nonlinear convergence, and Krylov techniques to solve the associated Jacobian (linear) systems. Krylov methods can be implemented Jacobian-free and can be preconditioned for efficiency. Successful preconditioning strategies have been developed for 2D incompressible resistive(L. Chacón et al., phJ. Comput. Phys). 178 (1), 15- 36 (2002) and Hall(L. Chacón and D. A. Knoll, phJ. Comput. Phys.), 188 (2), 573-592 (2003) MHD models. These are based on ``physics-based'' ideas, in which knowledge of the physics is exploited to derive well-conditioned (diagonally-dominant) approximations to the original system that are amenable to optimal solver technologies (multigrid). In this work, we will describe the status of the extension of the 2D preconditioning ideas for a 3D compressible, single-fluid XMHD model.

Large N critical exponents for the chiral Heisenberg Gross-Neveu universality class

NASA Astrophysics Data System (ADS)

Gracey, J. A.

2018-05-01

We compute the large N critical exponents η , ηϕ and 1 /ν in d dimensions in the chiral Heisenberg Gross-Neveu model to several orders in powers of 1 /N . For instance, the large N conformal bootstrap method is used to determine η at O (1 /N3) while the other exponents are computed to O (1 /N2). Estimates of the exponents for a phase transition in graphene are given which are shown to be commensurate with other approaches. In particular the behavior of the exponents in 2

Precise Measurement of Long-Range Heteronuclear Coupling Constants by a Novel Broadband Proton–Proton-Decoupled CPMG-HSQMBC Method

PubMed Central

Timári, István; Illyés, Tünde Z; Adams, Ralph W; Nilsson, Mathias; Szilágyi, László; Morris, Gareth A; Kövér, Katalin E

2015-01-01

A broadband proton–proton-decoupled CPMG-HSQMBC method for the precise and direct measurement of long-range heteronuclear coupling constants is presented. The Zangger–Sterk-based homodecoupling scheme reported herein efficiently removes unwanted proton–proton splittings from the heteronuclear multiplets, so that the desired heteronuclear couplings can be determined simply by measuring frequency differences between singlet maxima in the resulting spectra. The proposed pseudo-1D/2D pulse sequences were tested on nucleotides, a metal complex incorporating P heterocycles, and diglycosyl (di)selenides, as well as on other carbohydrate derivatives, for the extraction of nJ(1H,31P), nJ(1H,77Se), and nJ(1H,13C) values, respectively. PMID:25573660

Space-Time Earthquake Prediction: The Error Diagrams

NASA Astrophysics Data System (ADS)

Molchan, G.

2010-08-01

The quality of earthquake prediction is usually characterized by a two-dimensional diagram n versus τ, where n is the rate of failures-to-predict and τ is a characteristic of space-time alarm. Unlike the time prediction case, the quantity τ is not defined uniquely. We start from the case in which τ is a vector with components related to the local alarm times and find a simple structure of the space-time diagram in terms of local time diagrams. This key result is used to analyze the usual 2-d error sets { n, τ w } in which τ w is a weighted mean of the τ components and w is the weight vector. We suggest a simple algorithm to find the ( n, τ w ) representation of all random guess strategies, the set D, and prove that there exists the unique case of w when D degenerates to the diagonal n + τ w = 1. We find also a confidence zone of D on the ( n, τ w ) plane when the local target rates are known roughly. These facts are important for correct interpretation of ( n, τ w ) diagrams when we discuss the prediction capability of the data or prediction methods.

Weighted SGD for ℓp Regression with Randomized Preconditioning*

PubMed Central

Yang, Jiyan; Chow, Yin-Lam; Ré, Christopher; Mahoney, Michael W.

2018-01-01

In recent years, stochastic gradient descent (SGD) methods and randomized linear algebra (RLA) algorithms have been applied to many large-scale problems in machine learning and data analysis. SGD methods are easy to implement and applicable to a wide range of convex optimization problems. In contrast, RLA algorithms provide much stronger performance guarantees but are applicable to a narrower class of problems. We aim to bridge the gap between these two methods in solving constrained overdetermined linear regression problems—e.g., ℓ2 and ℓ1 regression problems. We propose a hybrid algorithm named pwSGD that uses RLA techniques for preconditioning and constructing an importance sampling distribution, and then performs an SGD-like iterative process with weighted sampling on the preconditioned system.By rewriting a deterministic ℓp regression problem as a stochastic optimization problem, we connect pwSGD to several existing ℓp solvers including RLA methods with algorithmic leveraging (RLA for short).We prove that pwSGD inherits faster convergence rates that only depend on the lower dimension of the linear system, while maintaining low computation complexity. Such SGD convergence rates are superior to other related SGD algorithm such as the weighted randomized Kaczmarz algorithm.Particularly, when solving ℓ1 regression with size n by d, pwSGD returns an approximate solution with ε relative error in the objective value in 𝒪(log n·nnz(A)+poly(d)/ε2) time. This complexity is uniformly better than that of RLA methods in terms of both ε and d when the problem is unconstrained. In the presence of constraints, pwSGD only has to solve a sequence of much simpler and smaller optimization problem over the same constraints. In general this is more efficient than solving the constrained subproblem required in RLA.For ℓ2 regression, pwSGD returns an approximate solution with ε relative error in the objective value and the solution vector measured in prediction norm in 𝒪(log n·nnz(A)+poly(d) log(1/ε)/ε) time. We show that for unconstrained ℓ2 regression, this complexity is comparable to that of RLA and is asymptotically better over several state-of-the-art solvers in the regime where the desired accuracy ε, high dimension n and low dimension d satisfy d ≥ 1/ε and n ≥ d2/ε. We also provide lower bounds on the coreset complexity for more general regression problems, indicating that still new ideas will be needed to extend similar RLA preconditioning ideas to weighted SGD algorithms for more general regression problems. Finally, the effectiveness of such algorithms is illustrated numerically on both synthetic and real datasets, and the results are consistent with our theoretical findings and demonstrate that pwSGD converges to a medium-precision solution, e.g., ε = 10−3, more quickly. PMID:29782626

Expression of NMDA receptor subunits in human blood lymphocytes: A peripheral biomarker in online computer game addiction.

PubMed

Sadat-Shirazi, Mitra-Sadat; Vousooghi, Nasim; Alizadeh, Bentolhoda; Makki, Seyed Mohammad; Zarei, Seyed Zeinolabedin; Nazari, Shahrzad; Zarrindast, Mohammad Reza

2018-05-23

Background and aims Repeated performance of some behaviors such as playing computer games could result in addiction. The NMDA receptor is critically involved in the development of behavioral and drug addictions. It has been claimed that the expression level of neurotransmitter receptors in the brain may be reflected in peripheral blood lymphocytes (PBLs). Methods Here, using a real-time PCR method, we have investigated the mRNA expression of GluN2A, GluN2D, GluN3A, and GluN3B subunits of the NMDA receptor in PBLs of male online computer game addicts (n = 25) in comparison with normal subjects (n = 26). Results Expression levels of GluN2A, GluN2D, and GluN3B subunits were not statistically different between game addicts and the control group. However, the mRNA expression of the GluN3A subunit was downregulated in PBLs of game addicts. Discussion and conclusions Transcriptional levels of GluN2A and GluN2D subunits in online computer game addicts are similar to our previously reported data of opioid addiction and are not different from the control group. However, unlike our earlier finding of drug addiction, the mRNA expression levels of GluN3A and GluN3B subunits in PBLs of game addicts are reduced and unchanged, respectively, compared with control subjects. It seems that the downregulated state of the GluN3A subunit of NMDA receptor in online computer game addicts is a finding that deserves more studies in the future to see whether it can serve as a peripheral biomarker in addiction studies, where the researcher wants to rule out the confusing effects of abused drugs.

Infrared spectra and anharmonic coupling of proton-bound nitrogen dimers N2-H+-N2, N2-D+-N2, and 15N2-H+-15N2 in solid para-hydrogen.

PubMed

Liao, Hsin-Yi; Tsuge, Masashi; Tan, Jake A; Kuo, Jer-Lai; Lee, Yuan-Pern

2017-08-09

The proton-bound nitrogen dimer, N 2 -H + -N 2 , and its isotopologues were investigated by means of vibrational spectroscopy. These species were produced upon electron bombardment of mixtures of N 2 (or 15 N 2 ) and para-hydrogen (p-H 2 ) or normal-D 2 (n-D 2 ) during deposition at 3.2 K. Reduced-dimension anharmonic vibrational Schrödinger equations were constructed to account for the strong anharmonic effects in these protonated species. The fundamental lines of proton motions in N 2 -H + -N 2 were observed at 715.0 (NH + N antisymmetric stretch, ν 4 ), 1129.6 (NH + N bend, ν 6 ), and 2352.7 (antisymmetric NN/NN stretch, ν 3 ) cm -1 , in agreement with values of 763, 1144, and 2423 cm -1 predicted with anharmonic calculations using the discrete-variable representation (DVR) method at the CCSD/aug-cc-pVDZ level. The lines at 1030.2 and 1395.5 cm -1 were assigned to combination bands involving nν 2 + ν 4 (n = 1 and 2) according to theoretical calculations; ν 2 is the N 2 N 2 stretching mode. For 15 N 2 -H + - 15 N 2 in solid p-H 2 , the corresponding major lines were observed at 710.0 (ν 4 ), 1016.7 (ν 2 + ν 4 ), 1124.3 (ν 6 ), 1384.8 (2ν 2 + ν 4 ), and 2274.9 (ν 3 ) cm -1 . For N 2 -D + -N 2 in solid n-D 2 , the corresponding major lines were observed at 494.0 (ν 4 ), 840.7 (ν 2 + ν 4 ), 825.5 (ν 6 ), and 2356.2 (ν 3 ) cm -1 . In addition, two lines at 762.0 (weak) and 808.3 cm -1 were tentatively assigned to be some modes of N 2 -H + -N 2 perturbed or activated by a third N 2 near the proton.

A sensitive and efficient method for determination of N-acetylhexosamines and N-acetylneuraminic acid in breast milk and milk-based products by high-performance liquid chromatography via UV detection and mass spectrometry identification.

PubMed

Chuanxiang, Wu; Lian, Xia; Lijie, Liu; Fengli, Qu; Zhiwei, Sun; Xianen, Zhao; Jinmao, You

2016-02-01

A sensitive and efficient method of high performance liquid chromatography using 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) as pre-column derivatization reagent coupled with UV detection (HPLC-UV) and online mass spectrometry identification was established for determination of the most common N-Acetylhexosamines (N-acetyl-d-glucosamine (GlcNAc) and N-acetyl-d-galactosamine (GalNAc)) and N-acetylneuraminic acid (Neu5Ac). In order to obtain the highest liberation level of the three monosaccharides without destruction of Neu5Ac or conversion of GlcNAc/GalNAc to GlcN/GalN in the hydrolysis procedure, the pivotal parameters affecting the liberation of N-acetylhexosamines/Neu5Ac from sample were investigated with response surface methodology (RSM). Under the optimized condition, maximum yield was obtained. The effects of key parameters on derivatization, separation and detection were also investigated. At optimized conditions, three monosaccharides were labeled fast and entirely, and all derivatives exhibited a good baseline resolution and high detection sensitivity. The developed method was linear over the calibration range 0.25-12μM, with R(2)>0.9991. The detection limits of the method were between 0.48 and 2.01pmol. Intra- and inter-day precisions for the three monosaccharides (GlcNAc, GalNAc and Neu5Ac) were found to be in the range of 3.07-4.02% and 3.69-4.67%, respectively. Individual monosaccharide recovery from spiked milk was in the range of 81%-97%. The sensitivity of the method, the facility of the derivatization procedure and the reliability of the hydrolysis conditions suggest the proposed method has a high potential for utilization in routine trace N-acetylhexosamines and Neu5Ac analysis in biological samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Stereoscopic neuroanatomy lectures using a three-dimensional virtual reality environment.

PubMed

Kockro, Ralf A; Amaxopoulou, Christina; Killeen, Tim; Wagner, Wolfgang; Reisch, Robert; Schwandt, Eike; Gutenberg, Angelika; Giese, Alf; Stofft, Eckart; Stadie, Axel T

2015-09-01

Three-dimensional (3D) computer graphics are increasingly used to supplement the teaching of anatomy. While most systems consist of a program which produces 3D renderings on a workstation with a standard screen, the Dextrobeam virtual reality VR environment allows the presentation of spatial neuroanatomical models to larger groups of students through a stereoscopic projection system. Second-year medical students (n=169) were randomly allocated to receive a standardised pre-recorded audio lecture detailing the anatomy of the third ventricle accompanied by either a two-dimensional (2D) PowerPoint presentation (n=80) or a 3D animated tour of the third ventricle with the DextroBeam. Students completed a 10-question multiple-choice exam based on the content learned and a subjective evaluation of the teaching method immediately after the lecture. Students in the 2D group achieved a mean score of 5.19 (±2.12) compared to 5.45 (±2.16) in the 3D group, with the results in the 3D group statistically non-inferior to those of the 2D group (p<0.0001). The students rated the 3D method superior to 2D teaching in four domains (spatial understanding, application in future anatomy classes, effectiveness, enjoyableness) (p<0.01). Stereoscopically enhanced 3D lectures are valid methods of imparting neuroanatomical knowledge and are well received by students. More research is required to define and develop the role of large-group VR systems in modern neuroanatomy curricula. Copyright © 2015 Elsevier GmbH. All rights reserved.

Utility of N-Bromosuccinimide for the Titrimetric and Spectrophotometric Determination of Famotidine in Pharmaceutical Formulations

PubMed Central

Zenita, O.; Basavaiah, K.

2011-01-01

Two titrimetric and two spectrophotometric methods are described for the assay of famotidine (FMT) in tablets using N-bromosuccinimide (NBS). The first titrimetric method is direct in which FMT is titrated directly with NBS in HCl medium using methyl orange as indicator (method A). The remaining three methods are indirect in which the unreacted NBS is determined after the complete reaction between FMT and NBS by iodometric back titration (method B) or by reacting with a fixed amount of either indigo carmine (method C) or neutral red (method D). The method A and method B are applicable over the range of 2–9 mg and 1–7 mg, respectively. In spectrophotometric methods, Beer's law is obeyed over the concentration ranges of 0.75–6.0 μg mL−1 (method C) and 0.3–3.0 μg mL−1 (method D). The applicability of the developed methods was demonstrated by the determination of FMT in pure drug as well as in tablets. PMID:21760785

L2 Milestone: Neutron Capture Cross Sections from Surrogate (p, d) Measurements: Determination of the Unknown 87Y(n, g) Cross Section and Assessment of the Method Via the 90Zr(n, g) Benchmark Case: Theory Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Escher, J. E.

Cross sections for compound-nuclear reactions involving unstable targets are important for many applications, but can often not be measured directly. Here we describe a method for extracting cross sections for neutron-capture on unstable isotopes from indirect (surrogate) measurements. The surrogate reaction, which produces the compound nucleus of interest, has to be described and the decay of the nucleus has to be modeled. We outline the approach for one-neutron pickup and report on the determination of the 90Zr(n, γ ) reaction from surrogate 92Zr(p,d) data, which is compared to the directly-measured capture cross section and thus provides a benchmark for themore » method. We then apply the method to determine the 87Y(n, γ ) cross section, which has not been measured directly. The work was carried out in the context of an LLNL L2 Milestone. This report addresses the theory aspects of the milestone. A complementary document summarizes the experimental efforts [1].« less

Abnormal functional connectivity of the posterior cingulate cortex is associated with depressive symptoms in patients with Alzheimer’s disease

PubMed Central

Zhang, Jiangtao; Guo, Zhongwei; Liu, Xiaozheng; Jia, Xize; Li, Jiapeng; Li, Yaoyao; Lv, Danmei; Chen, Wei

2017-01-01

Background Depressive symptoms are significant and very common psychiatric complications in patients with Alzheimer’s disease (AD), which can aggravate the decline in social function. However, changes in the functional connectivity (FC) of the brain in AD patients with depressive symptoms (D-AD) remain unclear. Objective To investigate whether any differences exist in the FC of the posterior cingulate cortex (PCC) between D-AD patients and non-depressed AD patients (nD-AD). Materials and methods We recruited 15 D-AD patients and 17 age-, sex-, educational level-, and Mini-Mental State Examination (MMSE)-matched nD-AD patients to undergo tests using the Neuropsychiatric Inventory, Hamilton Depression Rating Scale, and 3.0T resting-state functional magnetic resonance imaging. Bilateral PCC were selected as the regions of interest and between-group differences in the PCC FC network were assessed using Student’s t-test. Results Compared with the nD-AD group, D-AD patients showed increased PCC FC in the right amygdala, right parahippocampus, right superior temporal pole, right middle temporal lobe, right middle temporal pole, and right hippocampus (AlphaSim correction; P<0.05). In the nD-AD group, MMSE scores were positively correlated with PCC FC in the right superior temporal pole and right hippocampus (false discovery rate corrected; P<0.05). Conclusion Differences were detected in PCC FC between nD-AD and D-AD patients, which may be related to depressive symptoms. Our study provides a significant enhancement to our understanding of the functional mechanisms underlying D-AD. PMID:29066900

Surface functionalization of two-dimensional metal chalcogenides by Lewis acid-base chemistry

NASA Astrophysics Data System (ADS)

Lei, Sidong; Wang, Xifan; Li, Bo; Kang, Jiahao; He, Yongmin; George, Antony; Ge, Liehui; Gong, Yongji; Dong, Pei; Jin, Zehua; Brunetto, Gustavo; Chen, Weibing; Lin, Zuan-Tao; Baines, Robert; Galvão, Douglas S.; Lou, Jun; Barrera, Enrique; Banerjee, Kaustav; Vajtai, Robert; Ajayan, Pulickel

2016-05-01

Precise control of the electronic surface states of two-dimensional (2D) materials could improve their versatility and widen their applicability in electronics and sensing. To this end, chemical surface functionalization has been used to adjust the electronic properties of 2D materials. So far, however, chemical functionalization has relied on lattice defects and physisorption methods that inevitably modify the topological characteristics of the atomic layers. Here we make use of the lone pair electrons found in most of 2D metal chalcogenides and report a functionalization method via a Lewis acid-base reaction that does not alter the host structure. Atomic layers of n-type InSe react with Ti4+ to form planar p-type [Ti4+n(InSe)] coordination complexes. Using this strategy, we fabricate planar p-n junctions on 2D InSe with improved rectification and photovoltaic properties, without requiring heterostructure growth procedures or device fabrication processes. We also show that this functionalization approach works with other Lewis acids (such as B3+, Al3+ and Sn4+) and can be applied to other 2D materials (for example MoS2, MoSe2). Finally, we show that it is possible to use Lewis acid-base chemistry as a bridge to connect molecules to 2D atomic layers and fabricate a proof-of-principle dye-sensitized photosensing device.

Effect of D23N mutation on the dimer conformation of amyloid β-proteins: ab initio molecular simulations in water.

PubMed

Okamoto, Akisumi; Yano, Atsushi; Nomura, Kazuya; Higai, Shin'ichi; Kurita, Noriyuki

2014-05-01

The molecular pathogenesis of Alzheimer's disease (AD) is deeply involved in aggregations of amyloid β-proteins (Aβ) in a diseased brain. The recent experimental studies indicated that the mutation of Asp23 by Asn (D23N) within the coding sequence of Aβ increases the risk for the pathogeny of cerebral amyloid angiopathy and early-onset familial ADs. Fibrils of the D23N mutated Aβs can form both parallel and antiparallel structures, and the parallel one is considered to be associated with the pathogeny. However, the structure and the aggregation mechanism of the mutated Aβ fibrils are not elucidated at atomic and electronic levels. We here investigated solvated structures of the two types of Aβ dimers, each of which is composed of the wild-type or the D23N mutated Aβ, using classical molecular mechanics and ab initio fragment molecular orbital (FMO) methods, in order to reveal the effect of the D23N mutation on the structure of Aβ dimer as well as the specific interactions between the Aβ monomers. The results elucidate that the effect of the D23N mutation is significant for the parallel structure of Aβ dimer and that the solvating water molecules around the Aβ dimer have significant contribution to the stability of Aβ dimer. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluation of the new restandardized Abbott Architect 25-OH Vitamin D assay in vitamin D-insufficient and vitamin D-supplemented individuals.

PubMed

Annema, Wijtske; Nowak, Albina; von Eckardstein, Arnold; Saleh, Lanja

2017-09-19

Recently, Abbott Diagnostics has restandardized the Architect 25(OH)D assay against the NIST SRM 2972. We have evaluated the analytical and clinical performance of the restandardized Architect 25(OH)D assay and compared its performance with a NIST-traceable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and the Roche total 25(OH)D assay in vitamin D-insufficient individuals before and after vitamin D 3 supplementation. Frozen serum samples were obtained from 88 healthy subjects with self-perceived fatigue and vitamin D-insufficiency <50 nmol L -1 who were randomized to receive a single 100 000 IU dose of vitamin D 3 (n = 48) or placebo (n = 40). Total 25(OH)D concentrations were measured before and 4 weeks after supplementation by the restandardized Architect 25(OH)D assay, LC-MS/MS, and Roche assay. The Architect 25(OH)D assay showed an intra- and inter-assay imprecision of <5%. Comparison of the Architect assay with the LC-MS/MS method showed a good correlation in both vitamin D-insufficient and vitamin D-supplemented subjects, however, with a negative mean bias of 17.4% and 8.9%, respectively. As compared to the Roche assay, the Abbott assay underestimated 25(OH)D results in insufficient subjects (<50 nmol L -1 ) with a mean negative bias of 17.1%, this negative bias turned into a positive bias in supplemented subjects. Overall there was a moderate agreement in classification of vitamin D-insufficient and -supplemented individuals into different vitamin D states between the Architect 25(OH)D method and LC-MS/MS. The routine use of the restandardized Architect 25(OH)D results in a slight underestimation of circulating total 25(OH)D levels at lower concentrations and thus potential misclassification of vitamin D status. © 2017 Wiley Periodicals, Inc.

Ion chamber absorbed dose calibration coefficients, N{sub D,w}, measured at ADCLs: Distribution analysis and stability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muir, B. R., E-mail: Bryan.Muir@nrc-cnrc.gc.ca

2015-04-15

Purpose: To analyze absorbed dose calibration coefficients, N{sub D,w}, measured at accredited dosimetry calibration laboratories (ADCLs) for client ionization chambers to study (i) variability among N{sub D,w} coefficients for chambers of the same type calibrated at each ADCL to investigate ion chamber volume fluctuations and chamber manufacturing tolerances; (ii) equivalency of ion chamber calibration coefficients measured at different ADCLs by intercomparing N{sub D,w} coefficients for chambers of the same type; and (iii) the long-term stability of N{sub D,w} coefficients for different chamber types by investigating repeated chamber calibrations. Methods: Large samples of N{sub D,w} coefficients for several chamber types measuredmore » over the time period between 1998 and 2014 were obtained from the three ADCLs operating in the United States. These are analyzed using various graphical and numerical statistical tests for the four chamber types with the largest samples of calibration coefficients to investigate (i) and (ii) above. Ratios of calibration coefficients for the same chamber, typically obtained two years apart, are calculated to investigate (iii) above and chambers with standard deviations of old/new ratios less than 0.3% meet stability requirements for accurate reference dosimetry recommended in dosimetry protocols. Results: It is found that N{sub D,w} coefficients for a given chamber type compared among different ADCLs may arise from differing probability distributions potentially due to slight differences in calibration procedures and/or the transfer of the primary standard. However, average N{sub D,w} coefficients from different ADCLs for given chamber types are very close with percent differences generally less than 0.2% for Farmer-type chambers and are well within reported uncertainties. Conclusions: The close agreement among calibrations performed at different ADCLs reaffirms the Calibration Laboratory Accreditation Subcommittee process of ensuring ADCL conformance with National Institute of Standards and Technology standards. This study shows that N{sub D,w} coefficients measured at different ADCLs are statistically equivalent, especially considering reasonable uncertainties. This analysis of N{sub D,w} coefficients also allows identification of chamber types that can be considered stable enough for accurate reference dosimetry.« less

d-serine levels in Alzheimer's disease: implications for novel biomarker development

PubMed Central

Madeira, C; Lourenco, M V; Vargas-Lopes, C; Suemoto, C K; Brandão, C O; Reis, T; Leite, R E P; Laks, J; Jacob-Filho, W; Pasqualucci, C A; Grinberg, L T; Ferreira, S T; Panizzutti, R

2015-01-01

Alzheimer's disease (AD) is a severe neurodegenerative disorder still in search of effective methods of diagnosis. Altered levels of the NMDA receptor co-agonist, d-serine, have been associated with neurological disorders, including schizophrenia and epilepsy. However, whether d-serine levels are deregulated in AD remains elusive. Here, we first measured D-serine levels in post-mortem hippocampal and cortical samples from nondemented subjects (n=8) and AD patients (n=14). We next determined d-serine levels in experimental models of AD, including wild-type rats and mice that received intracerebroventricular injections of amyloid-β oligomers, and APP/PS1 transgenic mice. Finally, we assessed d-serine levels in the cerebrospinal fluid (CSF) of 21 patients with a diagnosis of probable AD, as compared with patients with normal pressure hydrocephalus (n=9), major depression (n=9) and healthy controls (n=10), and results were contrasted with CSF amyloid-β/tau AD biomarkers. d-serine levels were higher in the hippocampus and parietal cortex of AD patients than in control subjects. Levels of both d-serine and serine racemase, the enzyme responsible for d-serine production, were elevated in experimental models of AD. Significantly, d-serine levels were higher in the CSF of probable AD patients than in non-cognitively impaired subject groups. Combining d-serine levels to the amyloid/tau index remarkably increased the sensitivity and specificity of diagnosis of probable AD in our cohort. Our results show that increased brain and CSF d-serine levels are associated with AD. CSF d-serine levels discriminated between nondemented and AD patients in our cohort and might constitute a novel candidate biomarker for early AD diagnosis. PMID:25942042

Pre-analytical conditions in non-invasive prenatal testing of cell-free fetal RHD.

PubMed

Clausen, Frederik Banch; Jakobsen, Tanja Roien; Rieneck, Klaus; Krog, Grethe Risum; Nielsen, Leif Kofoed; Tabor, Ann; Dziegiel, Morten Hanefeld

2013-01-01

Non-invasive prenatal testing of cell-free fetal DNA (cffDNA) in maternal plasma can predict the fetal RhD type in D negative pregnant women. In Denmark, routine antenatal screening for the fetal RhD gene (RHD) directs the administration of antenatal anti-D prophylaxis only to women who carry an RhD positive fetus. Prophylaxis reduces the risk of immunization that may lead to hemolytic disease of the fetus and the newborn. The reliability of predicting the fetal RhD type depends on pre-analytical factors and assay sensitivity. We evaluated the testing setup in the Capital Region of Denmark, based on data from routine antenatal RHD screening. Blood samples were drawn at gestational age 25 weeks. DNA extracted from 1 mL of plasma was analyzed for fetal RHD using a duplex method for exon 7/10. We investigated the effect of blood sample transportation time (n = 110) and ambient outdoor temperatures (n = 1539) on the levels of cffDNA and total DNA. We compared two different quantification methods, the delta Ct method and a universal standard curve. PCR pipetting was compared on two systems (n = 104). The cffDNA level was unaffected by blood sample transportation for up to 9 days and by ambient outdoor temperatures ranging from -10 °C to 28 °C during transport. The universal standard curve was applicable for cffDNA quantification. Identical levels of cffDNA were observed using the two automated PCR pipetting systems. We detected a mean of 100 fetal DNA copies/mL at a median gestational age of 25 weeks (range 10-39, n = 1317). The setup for real-time PCR-based, non-invasive prenatal testing of cffDNA in the Capital Region of Denmark is very robust. Our findings regarding the transportation of blood samples demonstrate the high stability of cffDNA. The applicability of a universal standard curve facilitates easy cffDNA quantification.

Enantiomeric separation of seven β-agonists by NACE-Study of chiral selectivity with diacetone-d-mannitol-boric acid complex.

PubMed

Lv, Lili; Wang, Lijuan; Li, Jun; Jiao, Yajun; Gao, Shengnan; Wang, Jiachang; Yan, Hongyuan

2017-10-25

A rapid and effective nonaqueous capillary electrophoresis (NACE)-ultraviolet (UV) method was developed for the enantiomeric separation of seven β-agonists. Diacetone-d-mannitol-boric acid complex was used as a new chiral selector. It was in situ synthesized by the reaction of diacetone-d-mannitol and boric acid in methanol medium containing triethylamine. The effects of diacetone-d-mannitol, boric acid, and triethylamine concentrations on the enantioseparation were carefully investigated. Under the optimized conditions, baseline enantioseparation could be obtained for six of the tested β-agonists within 12min. These results were better than that obtained with d-mannitol-boric acid complex in previous work. 11 B nuclear magnetic resonance ( 11 B NMR) was applied to determine the fraction of boron species and confirm the formation of diacetone-d-mannitol-boric acid complex. Validation of the established NACE method was also carried out according to ICH guidelines. Calibration curves showed good linearity with correlation coefficients (r)≥0.9992 over a certain concentration range for each enantiomer of the tested five β-agonists. The relative standard deviations (RSDs) of intra-day precisions and inter-day precisions of migration times were ≤1.4% (n=6), and ≤6.3% (n=10), respectively. That of peak areas were ≤3.7% (n=6), and ≤5.6% (n=10), respectively. The limits of detection (LODs) and the limits of quantitation (LOQs) based on the signal-to-noise ratios of 3 and 10 were found below 1.25μgmL -1 and 5.00μgmL -1 , respectively. The proposed method was successfully applied to the determination of clenbuterol enantiomers in a multi-component pharmaceutical dosage form called "Ambroxol Hydrochloride and Clenbuterol Hydrochloride Oral Solution". Copyright © 2017 Elsevier B.V. All rights reserved.

[Accumulation responses of seeds and seedlings to 15N isotope for two typical broadleaved trees in Northeast China.

PubMed

Wang, Guang Chen; Song, Yuan; Yan, Qiao Ling; Zhang, Jin Xin

2016-08-01

Two typical broadleaved trees (i.e., Fraxinus rhynchophylla and Acer mono) with wind-dispersed seeds in Northeast China were selected in this study. A method of 15 N isotope labeling was used to explore the accumulation responses of seeds and seedlings to 15 N-urea soaking concentration (0, 0.05, 0.1 and 0.2 g·L -1 ), soaking time (4, 8 and 12 days) and leaf stage (2, 4, 6, and 8 leaves). The results showed that 15 N-urea soaking concentration and soaking time had significantly positive effects on δ 15 N values of seeds, i.e., higher 15 N-urea concentration and longer period of soaking (0.2 g·L -1 +12 d) were contributed to more 15 N accumulation of seeds. The maximum multiples of 15 N accumulation in F. rhynchophylla seeds and A. mono seeds were observed in 0.1 g·L -1 + (4 d, 8 d) and 0.05 g·L -1 + (4 d, 8 d), respectively. The loss rate of δ 15 N values decreased markedly from 2 leaves to 6 leaves and then kept relatively stable with the increasing seedling height, and the total δ 15 N values of seedlings started to decline at the stage of 8 leaves. These results suggested that seedlings with 6 leaves were more suitable for tracking seedling source. The δ 15 N values in leaves of seedlings were significantly positively correlated with 15 N-urea concentration level, soaking time and δ 15 N values of seeds. Overall, the accumulation of 15 N-urea could be found in seeds and seedlings of F. rhynchophylla and A. mono. The combination of 15 N-urea concentration (0.1 g·L -1 ), soaking time (8 d) and leaf stage (6 leaves) was the most suitable for tracking the seeds and seedlings of these two broadleaved trees.

Modeling Molecules

NASA Technical Reports Server (NTRS)

2000-01-01

The molecule modeling method known as Multibody Order (N) Dynamics, or MBO(N)D, was developed by Moldyn, Inc. at Goddard Space Flight Center through funding provided by the SBIR program. The software can model the dynamics of molecules through technology which stimulates low-frequency molecular motions and properties, such as movements among a molecule's constituent parts. With MBO(N)D, a molecule is substructured into a set of interconnected rigid and flexible bodies. These bodies replace the computation burden of mapping individual atoms. Moldyn's technology cuts computation time while increasing accuracy. The MBO(N)D technology is available as Insight II 97.0 from Molecular Simulations, Inc. Currently the technology is used to account for forces on spacecraft parts and to perform molecular analyses for pharmaceutical purposes. It permits the solution of molecular dynamics problems on a moderate workstation, as opposed to on a supercomputer.

Longevity of White Clover (Trifolium repens) Leaves, Stolons and Roots, and Consequences for Nitrogen Dynamics under Northern Temperate Climatic Conditions

PubMed Central

Sturite, Ievina; Henriksen, Trond Maukon; Breland, Tor Arvid

2007-01-01

Background and Aims White clover (Trifolium repens) is, due to nitrogen (N) fixation, important to the N dynamics of several northern temperate agroecosystems. This study aimed at monitoring growth and death of major white clover plant organs to assess their potential contribution to within-season N input and risk of off-season N losses. Methods White clover (‘Snowy’) was studied in a plot and root window experiment in southeast Norway (60°42′N, 10°51′E). Leaves, stolons and roots were tagged for lifespan measurement in harvested and unharvested stands during two experimental years. The availability of soil inorganic N was measured by plant root simulator (PRS™) probes. Key Results The longevity of leaves and petioles ranged from 21 to 86 d (mean = 59 d), of main stolon sections from 111 to over 677 d (mean = 411 d) and of roots from 27 to 621 d (mean = 290 d). About 60 % of the leaves produced had turned over by the end of the growing season and another 30 % had died or disappeared by the subsequent spring. Harvesting reduced the longevity of stolons and increased plant fragmentation, but did not decrease leaf or root lifespan or increase soil N availability. From the plant organ turnover data, it was estimated that the gross N input to the soil–plant system from white clover in pure stand during two growing seasons corresponded to a 2·5-fold increase over the total N in harvestable shoots. Conclusions The short lifespan and poor over-wintering of leaves showed their potential importance as a nitrogen source in the soil–plant ecosystem but also their potential contribution to the risk of off-season N losses. PMID:17495980

Overview of fast algorithm in 3D dynamic holographic display

NASA Astrophysics Data System (ADS)

Liu, Juan; Jia, Jia; Pan, Yijie; Wang, Yongtian

2013-08-01

3D dynamic holographic display is one of the most attractive techniques for achieving real 3D vision with full depth cue without any extra devices. However, huge 3D information and data should be preceded and be computed in real time for generating the hologram in 3D dynamic holographic display, and it is a challenge even for the most advanced computer. Many fast algorithms are proposed for speeding the calculation and reducing the memory usage, such as:look-up table (LUT), compressed look-up table (C-LUT), split look-up table (S-LUT), and novel look-up table (N-LUT) based on the point-based method, and full analytical polygon-based methods, one-step polygon-based method based on the polygon-based method. In this presentation, we overview various fast algorithms based on the point-based method and the polygon-based method, and focus on the fast algorithm with low memory usage, the C-LUT, and one-step polygon-based method by the 2D Fourier analysis of the 3D affine transformation. The numerical simulations and the optical experiments are presented, and several other algorithms are compared. The results show that the C-LUT algorithm and the one-step polygon-based method are efficient methods for saving calculation time. It is believed that those methods could be used in the real-time 3D holographic display in future.

Importance of the Electron Correlation and Dispersion Corrections in Calculations Involving Enamines, Hemiaminals, and Aminals. Comparison of B3LYP, M06-2X, MP2, and CCSD Results with Experimental Data.

PubMed

Castro-Alvarez, Alejandro; Carneros, Héctor; Sánchez, Dani; Vilarrasa, Jaume

2015-12-18

While B3LYP, M06-2X, and MP2 calculations predict the ΔG° values for exchange equilibria between enamines and ketones with similar acceptable accuracy, the M06-2X/6-311+G(d,p) and MP2/6-311+G(d,p) methods are required for enamine formation reactions (for example, for enamine 5a, arising from 3-methylbutanal and pyrrolidine). Stronger disagreement was observed when calculated energies of hemiaminals (N,O-acetals) and aminals (N,N-acetals) were compared with experimental equilibrium constants, which are reported here for the first time. Although it is known that the B3LYP method does not provide a good description of the London dispersion forces, while M06-2X and MP2 may overestimate them, it is shown here how large the gaps are and that at least single-point calculations at the CCSD(T)/6-31+G(d) level should be used for these reaction intermediates; CCSD(T)/6-31+G(d) and CCSD(T)/6-311+G(d,p) calculations afford ΔG° values in some cases quite close to MP2/6-311+G(d,p) while in others closer to M06-2X/6-311+G(d,p). The effect of solvents is similarly predicted by the SMD, CPCM, and IEFPCM approaches (with energy differences below 1 kcal/mol).

Tools to identify linear combination of prognostic factors which maximizes area under receiver operator curve.

PubMed

Todor, Nicolae; Todor, Irina; Săplăcan, Gavril

2014-01-01

The linear combination of variables is an attractive method in many medical analyses targeting a score to classify patients. In the case of ROC curves the most popular problem is to identify the linear combination which maximizes area under curve (AUC). This problem is complete closed when normality assumptions are met. With no assumption of normality search algorithm are avoided because it is accepted that we have to evaluate AUC n(d) times where n is the number of distinct observation and d is the number of variables. For d = 2, using particularities of AUC formula, we described an algorithm which lowered the number of evaluations of AUC from n(2) to n(n-1) + 1. For d > 2 our proposed solution is an approximate method by considering equidistant points on the unit sphere in R(d) where we evaluate AUC. The algorithms were applied to data from our lab to predict response of treatment by a set of molecular markers in cervical cancers patients. In order to evaluate the strength of our algorithms a simulation was added. In the case of no normality presented algorithms are feasible. For many variables computation time could be increased but acceptable.

2D materials integrated in Si3N4 photonics platform

NASA Astrophysics Data System (ADS)

Faneca, Joaquin; Hogan, Benjamin T.; Torres Alonso, E.; Craciun, Monica; Baldycheva, Anna

2018-02-01

In this paper, we discuss a back-end CMOS fabrication process for the large-scale integration of 2D materials on SOI (siliconon-insulator) platform and present a complete theoretical study of the change in the effective refractive index of 2D materialsenabled silicon nitride waveguide structures. The chemical vapour deposition (CVD) and liquid exfoliation fabrication methods are described for the fabrication of graphene, WS2 and MoS2 thin films. Finite-difference frequency-domain (FDFD) approach and the Transfer Matrix Method were used in order to mathematically describe these structures. The introduction of thin films of 2D material onto Si3N4 waveguide structures allows manipulation of the optical characteristics to a high degree of precision by varying the Fermi-level through the engineering of the number of atomically thin layers or by electrical tuning, for example. Based on the proposed tuning approach, designs of graphene, WS2 and MoS2 enabled Si3N4 micro-ring structures are presented for the visible and NIR range, which demonstrate versatility and desirable properties for a wide range of applications, such as bio-chemical sensing and optical communications.

Simultaneous two-view epipolar geometry estimation and motion segmentation by 4D tensor voting.

PubMed

Tong, Wai-Shun; Tang, Chi-Keung; Medioni, Gérard

2004-09-01

We address the problem of simultaneous two-view epipolar geometry estimation and motion segmentation from nonstatic scenes. Given a set of noisy image pairs containing matches of n objects, we propose an unconventional, efficient, and robust method, 4D tensor voting, for estimating the unknown n epipolar geometries, and segmenting the static and motion matching pairs into n independent motions. By considering the 4D isotropic and orthogonal joint image space, only two tensor voting passes are needed, and a very high noise to signal ratio (up to five) can be tolerated. Epipolar geometries corresponding to multiple, rigid motions are extracted in succession. Only two uncalibrated frames are needed, and no simplifying assumption (such as affine camera model or homographic model between images) other than the pin-hole camera model is made. Our novel approach consists of propagating a local geometric smoothness constraint in the 4D joint image space, followed by global consistency enforcement for extracting the fundamental matrices corresponding to independent motions. We have performed extensive experiments to compare our method with some representative algorithms to show that better performance on nonstatic scenes are achieved. Results on challenging data sets are presented.

Prevalence and antibiotic resistance of Pseudomonas aeruginosa in water samples in central Italy and molecular characterization of oprD in imipenem resistant isolates

PubMed Central

Carloni, Elisa; Andreoni, Francesca; Magi, Silvia; Chironna, Maria; Brandi, Giorgio; Amagliani, Giulia

2017-01-01

Scope This study aimed to analyse the prevalence, antibiotic resistance and genetic relatedness of P. aeruginosa isolates obtained from potable and recreational water samples (n. 8,351) collected from different settings (swimming pools, n. 207; healthcare facilities, n 1,684; accommodation facilities, n. 1,518; municipal waterworks, n. 4,500; residential buildings, n. 235). Possible mechanisms underlying resistance to imipenem, with particular focus on those involving oprD-based uptake, were also explored. Methods and results Isolation and identification of Pseudomonas aeruginosa was performed according to the standardized procedure UNI EN ISO 16266:2008 followed by PCR confirmation. Antibiotic Susceptibility testing was conducted according to EUCAST standardized disk diffusion method. Genetic relatedness of strains was carried out by RAPD. The sequence of the oprD gene was analyzed by standard method. Fifty-three samples (0.63%) were positive for P. aeruginosa, of which 10/207 (4.83%) were from swimming pools. Five isolates (9.43%) were resistant to imipenem, one to Ticarcillin + Clavulanate, one to both Piperacillin and Ticarcillin + Clavulanate. The highest isolation rate of imipenem resistant P. aeruginosa was observed in swimming pool water. Identical RAPD profiles were found in isolates from the same location in the same year or even in different years. Conclusions Imipenem resistant strains were identified as carbapenemase-negative and resistance has been associated with inactivating mutations within the oprD gene, with a concomitant loss of porin. RAPD results proved that a water system can remain colonized by one strain for long periods and the contamination may be difficult to eradicate. This study has revealed the presence of P. aeruginosa in different water samples, including resistant strains, especially in swimming pools, and confirmed the role of porins as a contributing factor in carbapenem resistance in Gram-negative bacteria. PMID:29211780

dftools: Distribution function fitting

NASA Astrophysics Data System (ADS)

Obreschkow, Danail

2018-05-01

dftools, written in R, finds the most likely P parameters of a D-dimensional distribution function (DF) generating N objects, where each object is specified by D observables with measurement uncertainties. For instance, if the objects are galaxies, it can fit a mass function (D=1), a mass-size distribution (D=2) or the mass-spin-morphology distribution (D=3). Unlike most common fitting approaches, this method accurately accounts for measurement in uncertainties and complex selection functions.

Characterization of deamidation at Asn138 in L-chain of recombinant humanized Fab expressed from Pichia pastoris.

PubMed

Ohkuri, Takatoshi; Murase, Eri; Sun, Shu-Lan; Sugitani, Jun; Ueda, Tadashi

2013-10-01

A method was previously established for evaluating Asn deamidation by matrix-assisted laser desorption/ionization time of flight-mass spectrometry using endoproteinase Asp-N. In this study, we demonstrated that this method could be applied to the identification of the deamidation site of the humanized fragment antigen-binding (Fab). First, a system for expressing humanized Fab from methylotrophic yeast Pichia pastoris was constructed, resulting in the preparation of ∼30 mg of the purified humanized Fab from 1 l culture. Analysis of the L-chain derived from recombinant humanized Fab that was heated at pH 7 and 100°C for 1 h showed the deamidation at Asn138 in the constant region. Then, we prepared L-N138D Fab and L-N138A Fab and examined their properties. The circular dichroism (CD) spectrum of the L-N138D Fab was partially different from that of the wild-type Fab. The measurement of the thermostability showed that L-N138D caused a significant decrease in the thermostability of Fab. On the other hand, the CD spectrum and thermostability of L-N138A Fab showed the same behaviour as the wild-type Fab. Thus, it was suggested that the introduction of a negative charge at position 138 in the L-chain by the deamidation significantly affected the stability of humanized Fab.

The vitamin D status of the US population from 1988 to 2010 using standardized serum concentrations of 25-hydroxyvitamin D shows recent modest increases.

PubMed

Schleicher, Rosemary L; Sternberg, Maya R; Lacher, David A; Sempos, Christopher T; Looker, Anne C; Durazo-Arvizu, Ramon A; Yetley, Elizabeth A; Chaudhary-Webb, Madhulika; Maw, Khin L; Pfeiffer, Christine M; Johnson, Clifford L

2016-08-01

Temporal trends in the US population's vitamin D status have been uncertain because of nonstandardized serum 25-hydroxyvitamin D [25(OH)D] measurements. To accurately assess vitamin D status trends among those aged ≥12 y, we used data from the cross-sectional NHANESs. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measuring 25(OH)D (sum of 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3), calibrated to standard reference materials, was used to predict LC-MS/MS-equivalent concentrations from radioimmunoassay data (1988-2006 surveys; n = 38,700) and to measure LC-MS/MS concentrations (2007-2010 surveys; n = 12,446). Weighted arithmetic means and the prevalence of 25(OH)D above or below cutoff concentrations were calculated to evaluate long-term trends. Overall, mean predicted 25(OH)D showed no time trend from 1988 to 2006, but during 2007-2010 the mean measured 25(OH)D was 5-6 nmol/L higher. Those groups who showed the largest 25(OH)D increases (7-11 nmol/L) were older, female, non-Hispanic white, and vitamin D supplement users. During 1988-2010, the proportions of persons with 25(OH)D <40 nmol/L were 14-18% (overall), 46-60% (non-Hispanic blacks), 21-28% (Mexican Americans), and 6-10% (non-Hispanic whites). An accurate method for measuring 25(OH)D showed stable mean concentrations in the US population (1988-2006) and recent modest increases (2007-2010). Although it is unclear to what extent supplement usage compared with different laboratory methods explain the increases in 25(OH)D, the use of higher vitamin D supplement dosages coincided with the increase. Marked race-ethnic differences in 25(OH)D concentrations were apparent. These data provide the first standardized information about temporal trends in the vitamin D status of the US population. © 2016 American Society for Nutrition.

Synthesis and potential cytotoxic activity of some new benzoxazoles, imidazoles, benzimidazoles and tetrazoles.

PubMed

Arulmurugan, Subramaniyan; Kavitha, Helen P

2013-06-01

2 The present work deals with the synthesis of some novel heterocyclic compounds such as benzoxazoles , 7, 13 and 19, imidazoles 3, 8, 14 and 20, benzimidazoles 4, 9, 15 and 21, and tetrazoles 10, 16, and 22. The synthesized compounds were characterized by IR, 1H NMR, mass spectrometry and elemental analysis. The compounds were evaluated for cytotoxicity against human cancer cell lines such as MCF-7 (breast cancer) and HT-29 (colon cancer) by the MTT assay method. Among the tested compounds, 4,4'-sulfonylbis(N-(2-(1H-benzo[d]imidazol- -2-yl)ethyl)aniline (9), N-bis(2-(benzo[d]oxazol-2-yl)-ethyl)- 6-phenyl-1,3,5-triazine-2,4-diamine (13), N-bis(2-(1H-benzo[ d]imidazol-2-yl)ethyl)-6-phenyl-1,3,5-triazine-2,4-diamine (15) and N-tris(2-1H-benzo[d]imidazol-2-yl)ethyl)- 1,3,5-triazine-2,4,6-triamine (21) showed potent cytotoxicity.

Three-dimensional Aerographite-GaN hybrid networks: Single step fabrication of porous and mechanically flexible materials for multifunctional applications

PubMed Central

Schuchardt, Arnim; Braniste, Tudor; Mishra, Yogendra K.; Deng, Mao; Mecklenburg, Matthias; Stevens-Kalceff, Marion A.; Raevschi, Simion; Schulte, Karl; Kienle, Lorenz; Adelung, Rainer; Tiginyanu, Ion

2015-01-01

Three dimensional (3D) elastic hybrid networks built from interconnected nano- and microstructure building units, in the form of semiconducting-carbonaceous materials, are potential candidates for advanced technological applications. However, fabrication of these 3D hybrid networks by simple and versatile methods is a challenging task due to the involvement of complex and multiple synthesis processes. In this paper, we demonstrate the growth of Aerographite-GaN 3D hybrid networks using ultralight and extremely porous carbon based Aerographite material as templates by a single step hydride vapor phase epitaxy process. The GaN nano- and microstructures grow on the surface of Aerographite tubes and follow the network architecture of the Aerographite template without agglomeration. The synthesized 3D networks are integrated with the properties from both, i.e., nanoscale GaN structures and Aerographite in the form of flexible and semiconducting composites which could be exploited as next generation materials for electronic, photonic, and sensors applications. PMID:25744694

Molecular profiles of Venezuelan isolates of Trypanosoma sp. by random amplified polymorphic DNA method.

PubMed

Perrone, T M; Gonzatti, M I; Villamizar, G; Escalante, A; Aso, P M

2009-05-12

Nine Trypanosoma sp. Venezuelan isolates, initially presumed to be T. evansi, were collected from three different hosts, capybara (Apure state), horse (Apure state) and donkey (Guarico state) and compared by the random amplification polymorphic DNA technique (RAPD). Thirty-one to 46 reproducible fragments were obtained with 12 of the 40 primers that were used. Most of the primers detected molecular profiles with few polymorphisms between the seven horse, capybara and donkey isolates. Quantitative analyses of the RAPD profiles of these isolates revealed a high degree of genetic conservation with similarity coefficients between 85.7% and 98.5%. Ten of the primers generated polymorphic RAPD profiles with two of the three Trypanosoma sp. horse isolates, namely TeAp-N/D1 and TeGu-N/D1. The similarity coefficient between these two isolates and the rest, ranged from 57.9% to 68.4% and the corresponding dendrogram clustered TeAp-N/D1 and Te Gu-N/D1 in a genetically distinct group.

Effect of N Fertilization Pattern on Rice Yield, N Use Efficiency and Fertilizer–N Fate in the Yangtze River Basin, China

PubMed Central

Liu, Xiaowei; Wang, Huoyan; Zhou, Jianmin; Hu, Fengqin; Zhu, Dejin; Chen, Zhaoming; Liu, Yongzhe

2016-01-01

High N loss and low N use efficiency (NUE), caused by high N fertilizer inputs and inappropriate fertilization patterns, have become important issues in the rice (Oryza sativa L.) growing regions of southern China. Changing current farmer fertilizer practice (FFP, 225 kg ha–1 N as three applications, 40% as basal fertilizer, 30% as tillering fertilizer and 30% as jointing fertilizer) to one—time root—zone fertilization (RZF, 225 kg ha–1 N applied once into 10 cm deep holes positioned 5 cm from the rice root as basal fertilizer) will address this problem. A two—year field experiment covering two rice growing regions was conducted to investigate the effect of urea one—time RZF on rice growth, nutrient uptake, and NUE. The highest NH4+–N content for RZF at fertilizer point at 30 d and 60 d after fertilization were 861.8 and 369.9 mg kg–1 higher than FFP, respectively. Rice yield and total N accumulation of RZF increased by 4.3–44.9% and 12.7–111.2% compared to FFP, respectively. RZF reduced fertilizer—N loss by 56.3–81.9% compared to FFP. The NUEs following RZF (mean of 65.8% for the difference method and 43.7% for the labelled method) were significantly higher than FFP (mean of 35.7% for the difference method and 14.4% for the labelled method). In conclusion, RZF maintained substantial levels of fertilizer—N in the root—zone, which led to enhanced rice biomass and N uptake during the early growth stages, increased fertilizer—N residual levels and reduced fertilizer—N loss at harvest. RZF produced a higher yield increment and showed an increased capacity to resist environmental threats than FFP in sandy soils. Therefore, adopting suitable fertilizer patterns plays a key role in enhancing agricultural benefits. PMID:27861491

Characterization of HgCdTe and Related Materials and Substrates for Third Generation Infrared Detectors

DTIC Science & Technology

2012-12-01

metal-organic vapor phase epitaxy (MOVPE); (iii) convenient n-type and p- type dopants; (iv) versatile methods for forming mesas , planar homojunctions...S. Kim, E. Plis, J. B. Rodriguez , G. D. Bishop, Y. D. Sharma, L. R. Dawson, S. Krishna, J. Bundas, R. Cook, D. Burrows, R. Dennis, K. Patnaude, A

Improvement in social competence using a randomized trial of a theatre intervention for children with autism spectrum disorder

PubMed Central

Corbett, Blythe A.; Key, Alexandra P.; Qualls, Lydia; Fecteau, Stephanie; Newsom, Cassandra; Coke, Catherine; Yoder, Paul

2017-01-01

The efficacy of a peer-mediated, theatre-based intervention on social competence in participants with autism spectrum disorder (ASD) was tested. Thirty 8-to-14 year-olds with ASD were randomly assigned to the treatment (n = 17) or a wait-list control (n = 13) group. Immediately after treatment, group effects were seen on social ability (d = .77), communication symptoms (d = −.86), group play with toys in the company of peers (d = .77), immediate memory for faces as measured by neuropsychological (d = .75) and ERP methods (d = .93), delayed memory for faces (d = .98), and theory of mind (d = .99). At the 2-month follow-up period, group effects were detected on communication symptoms (d = .82). The results of this pilot clinical trial provide initial support for the efficacy of the theatre-based intervention. PMID:26419766

Histochemical Characterization of Oocytes in the Pink Cuskeel (Genypterus blacodes).

PubMed

Cohen, Stefanía; Petcoff, Gladys; Freijo, Roberto O; Portiansky, Enrique L; Barbeito, Claudio G; Macchi, Gustavo J; Díaz, Alcira O

2015-08-01

In the present study we histochemically and lectinhistochemically characterized the growing oocytes of the pink cuskeel (Genypterus blacodes). We used histochemical methods for the localization and characterization of glycoconjugates (GCs) and lectin histochemical techniques for the identification of specific sugar residues. We analyzed presence and distribution of GCs in the different structures of the growing follicles (cortical alveoli, globules, yolk granules and zona radiata). During the initial stage of vitellogenesis, the oocytes presented small yolk granules composed of GCs that gradually increased during exogenous vitellogenesis. These GCs contained moderate quantities of α-D-mannose, D-glucose, N-acetylglucosamine and N-acetyl-neuraminic acid. The cortical alveoli contained both neutral and carboxylated GCs, and lectin techniques detected N-acetylgalactosamine, galactose and L-fucose. The zona radiata showed a strong positive reaction to PAS and it reacted weakly with more specific techniques, such as KOH/PA*S and PA/Bh/KOH/PAS. This structure showed GCs with oxidizable vicinal diols, O-acyl sugars and sialic acid residues with different substitution types and presented N-acetylgalactosamine and L-fucose specific residues. The oocytes follicular envelope evidenced neutral and acidic non-sulfated GCs and high concentrations of α-D-mannose, D-glucose, galactose and N-acetylgalactosamine. The intergranular cytoplasmic GCs were mainly rich in α-D-mannose, D-glucose, N-acetylgalactosamine, N-acetylglucosamine and N-acetyl-neuraminic acid. These results enhance the comprehension of the structure and functionality of the pink cuskeel ovarian follicles, and provide a useful tool for the study of this tissue in other teleost species.

[The vitamin D nutritional status in Chinese urban women of child-bearing age from 2010 to 2012].

PubMed

Lu, J X; Liu, X B; Chen, J; Hu, Y C; Yun, C F; Li, W D; Wang, R; Yang, Y H; Mao, D Q; Piao, J H; Yang, X G; Yang, L C

2017-02-06

Objective: To evaluate the vitamin D nutritional status in Chinese women of child-bearing age by analyzing serum 25-hydroxyvitamin D level in 2010-2012. Methods: Data were obtained from the China Nutrition and Health Survey in 2010-2012. Using cluster sampling and proportional stratified random sampling, 1 514 women of child-bearing age (18-44 years old) from 34 metropolis and 41 small and medium-sized cities were included in this study. Demographic information was collected by questionnaire and serum 25-hydroxyvitamin D concentration was determined by radioimmunoassay, in accordance with the 2010 Institute of Medicine of the National Academies standards. We compared differences in vitamin D levels, specifically serious deficiency, lack of deficiency, insufficiency, and excess. Results: The overall serum 25-hydroxyvitamin D level of Chinese urban women of child-bearing age ( P (50) ( P (25)- P (75))) was 20.1 (15.1-26.3) ng/ml; minorities had a significantly higher serum 25-hydroxyvitamin D level of 22.0 (15.9-27.5) ng/ml compared with women of Han nationality (19.8 (14.9-26.2) ng/ml) (χ(2)=7.02, P= 0.008). The proportions of women with serious deficiency, lack of deficiency, insufficiency, and excess vitamin D were 11.6% ( n= 175), 37.9% ( n= 574), 35.1% ( n= 531), and 0.3% ( n= 5), respectively. Only 15.1% ( n= 229) of women of child-bearing age had normal vitamin D nutritional status. No significant differences in vitamin D nutritional status were observed according to age, body mass index, city, nationality, educational level, marital status, or household income per capita ( P> 0.05). Conclusion: Most Chinese urban women of child-bearing age have poor vitamin D levels and require vitamin D supplementation.

Molecular structure, vibrational spectra, NLO and MEP analysis of bis[2-hydroxy-кO-N-(2-pyridyl)-1-naphthaldiminato-кN]zinc(II)

NASA Astrophysics Data System (ADS)

Tanak, Hasan; Toy, Mehmet

2013-11-01

The molecular geometry and vibrational frequencies of bis[2-hydroxy-кO-N-(2-pyridyl)-1-naphthaldiminato-кN]zinc(II) in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (B3LYP) with 6-311G(d,p) basis set. The results of the optimized molecular structure are presented and compared with the experimental X-ray diffraction. The energetic and atomic charge behavior of the title compound in solvent media has been examined by applying the Onsager and the polarizable continuum model. To investigate second order nonlinear optical properties of the title compound, the electric dipole (μ), linear polarizability (α) and first-order hyperpolarizability (β) were computed using the density functional B3LYP and CAM-B3LYP methods with the 6-31+G(d) basis set. According to our calculations, the title compound exhibits nonzero (β) value revealing second order NLO behavior. In addition, DFT calculations of the title compound, molecular electrostatic potential (MEP), frontier molecular orbitals, and thermodynamic properties were performed at B3LYP/6-311G(d,p) level of theory.

Ion Dynamics of a BHT-600 Hall Thruster Measured with Time-Resolved Laser-Induced Fluorescence

DTIC Science & Technology

2016-01-14

LIF  Method V = 0 V V λ = λ0 λ > λ0 λ < λ0 Ion Velocity from  Doppler Shift: 0 5 10 15 20 25 30 0 0.1 0.2 0.3 0.4...0.5 0.6 0.7 0.8 0.9 1 Frequency (GHz) N o r m a l i z e d S i g n a l xneg28z6_AVG OG LIF OG Fit LIF Fit AFRL | BHT‐600 TRLIF | Jan 14, 2016 10...Distribution A: Approved for Public Release; Distribution Unlimited. PA# 16204 Time‐Resolved  LIF  Method Laser  Tapered Amp  D1  BS1  BS2  D2  O G C  

Evaluation of tranche in securitization and long-range Ising model

NASA Astrophysics Data System (ADS)

Kitsukawa, K.; Mori, S.; Hisakado, M.

2006-08-01

This econophysics work studies the long-range Ising model of a finite system with N spins and the exchange interaction J/N and the external field H as a model for homogeneous credit portfolio of assets with default probability Pd and default correlation ρd. Based on the discussion on the (J,H) phase diagram, we develop a perturbative calculation method for the model and obtain explicit expressions for Pd,ρd and the normalization factor Z in terms of the model parameters N and J,H. The effect of the default correlation ρd on the probabilities P(Nd,ρd) for Nd defaults and on the cumulative distribution function D(i,ρd) are discussed. The latter means the average loss rate of the“tranche” (layered structure) of the securities (e.g. CDO), which are synthesized from a pool of many assets. We show that the expected loss rate of the subordinated tranche decreases with ρd and that of the senior tranche increases linearly, which are important in their pricing and ratings.

De novo synthesis of trideuteromethyl esters of amino acids for use in GC-MS and GC-tandem MS exemplified for ADMA in human plasma and urine: standardization, validation, comparison and proof of evidence for their aptitude as internal standards.

PubMed

Tsikas, Dimitrios

2009-08-01

Asymmetric dimethylarginine (ADMA, N(G),N(G)-dimethyl-L-arginine) is an endogenous inhibitor of nitric oxide (NO) synthesis, a potential risk factor for cardiovascular diseases and a powerful biochemical parameter in clinical studies. In our previous work we have reported on a GC-tandem MS method for the accurate and precise quantification of ADMA in biological fluids using de novo synthesized [(2)H(3)]-methyl ester ADMA (d(3)Me-ADMA) as internal standard (IS). This method provides basal ADMA concentrations in biological fluids that agree with those obtained by other groups using other validated methods for ADMA. Unanimously, de novo synthesized stable-isotope labeled analogues are considered not ideal IS, because they must be prepared in a matrix different from the biological sample. Recently, [2,3,3,4,4,5,5-(2)H(7)]-ADMA (d(7)-ADMA) has become commercially available and we took this opportunity to test the reliability of the de novo synthesized d(3)Me-ADMA as an IS for ADMA in GC-tandem MS. In this article, we report on the re-validation of the previously reported GC-tandem MS method for ADMA in human plasma and urine using d(7)-ADMA as IS, and on comparative quantitative analyses of ADMA by GC-tandem MS using d(7)-ADMA and d(3)Me-ADMA. After thorough standardization of d(7)-ADMA and methods validation, we obtained by GC-tandem MS very similar ADMA concentrations in plasma and urine using d(7)-ADMA and d(3)Me-ADMA. The present study gives a proof of evidence for the aptitude of (2)H(3)-ADMA as IS in GC-tandem MS and suggests that de novo synthesis of stable-isotope labeled alkyl esters of amino acids and amino acid derivates may be a generally applicable method in mass spectrometry-based methods for amino acids. This approach is especially useful for amino acids for which no stable-isotope labeled analogues are commercially available.

Three-Dimensional Macroporous Polypyrrole-Derived Graphene Electrode Prepared by the Hydrogen Bubble Dynamic Template for Supercapacitors and Metal-Free Catalysts.

PubMed

Yang, Xiaoqing; Liu, Anran; Zhao, Yuewu; Lu, Huijia; Zhang, Yuanjian; Wei, Wei; Li, Ying; Liu, Songqin

2015-10-28

We report a general method for the fabrication of three-dimensional (3D) macroporous graphene/conducting polymer modified electrode and nitrogen-doped graphene modified electrode. This method involves three consecutive steps. First, the 3D macroporous graphene (3D MG) electrode was fabricated electrochemically by reducing graphene oxide dispersion on different conducting substrates and used hydrogen bubbles as the dynamic template. The morphology and pore size of 3D MG could be governed by the use of surfactants and the dynamics of bubble generation and departure. Second, 3D macroporous graphene/polypyrrole (MGPPy) composites were constructed via directly electropolymerizing pyrrole monomer onto the networks of 3D MG. Due to the benefit of the good conductivity of 3D MG and pseudocapacitance of PPy, the composites manifest outstanding area specific capacitance of 196 mF cm(-2) at a current density of 1 mA cm(-2). The symmetric supercapacitor device assembled by the composite materials had a good capacity property. Finally, the nitrogen-doped MGPPy (N-MGPPy or MGPPy-X) with 3D macroporous nanostructure and well-regulated nitrogen doping was prepared via thermal treatment of the composites. The resultant N-MGPPy electrode was explored as a good electrocatalyst for the oxygen reduction reaction (ORR) with the current density value of 5.56 mA cm(-2) (-0.132 V vs Ag/AgCl). Moreover, the fuel tolerance and durability under the electrochemical environment of the N-MGPPy catalyst were found to be superior to the Pt/C catalyst.

MurD ligase from E. coli: Tetrahedral intermediate formation study by hybrid quantum mechanical/molecular mechanical replica path method.

PubMed

Perdih, Andrej; Hodoscek, Milan; Solmajer, Tom

2009-02-15

MurD (UDP-N-acetylmuramoyl-L-alanine:D-glutamate ligase), a three-domain bacterial protein, catalyses a highly specific incorporation of D-glutamate to the cytoplasmic intermediate UDP-N-acetyl-muramoyl-L-alanine (UMA) utilizing ATP hydrolysis to ADP and P(i). This reaction is part of a biosynthetic path yielding bacterial peptidoglycan. On the basis of structural studies of MurD complexes, a stepwise catalytic mechanism was proposed that commences with a formation of the acyl-phosphate intermediate, followed by a nucleophilic attack of D-glutamate that, through the formation of a tetrahedral reaction intermediate and subsequent phosphate dissociation, affords the final product, UDP-N-acetyl-muramoyl-L-alanine-D-glutamate (UMAG). A hybrid quantum mechanical/molecular mechanical (QM/MM) molecular modeling approach was utilized, combining the B3LYP QM level of theory with empirical force field simulations to evaluate three possible reaction pathways leading to tetrahedral intermediate formation. Geometries of the starting structures based on crystallographic experimental data and tetrahedral intermediates were carefully examined together with a role of crucial amino acids and water molecules. The replica path method was used to generate the reaction pathways between the starting structures and the corresponding tetrahedral reaction intermediates, offering direct comparisons with a sequential kinetic mechanism and the available structural data for this enzyme. The acquired knowledge represents new and valuable information to assist in the ongoing efforts leading toward novel inhibitors of MurD as potential antibacterial drugs. (c) 2008 Wiley-Liss, Inc.

Vulnerability Assessment Using a Fuzzy Logic Based Method

DTIC Science & Technology

1993-12-01

evaluating computer security vulnerabilities is very labor intensive. To help ease this workload, this thesis presents two automated methods possibly...eal 3n, 0 e) 0 n It -f0 . nts reg"roreg Iths OU raen estre -tte In Vt )thef awfict Of this ~.,i~t 14,-, A I’ K1- 2 3" toe 17 %1d3.rV. ~ 0 C .~ Ats ,glt

Tests of constituent-quark generation methods which maintain both the nucleon center of mass and the desired radial distribution in Monte Carlo Glauber models

DOE PAGES

Mitchell, J. T.; Perepelitsa, D. V.; Tannenbaum, M. J.; ...

2016-05-23

Here, several methods of generating three constituent quarks in a nucleon are evaluated which explicitly maintain the nucleon's center of mass and desired radial distribution and can be used within Monte Carlo Glauber frameworks. The geometric models provided by each method are used to generate distributions over the number of constituent quark participants ( N qp) in p+p,d+Au, and Au+Au collisions. The results are compared with each other and to a previous result of N qp calculations, without this explicit constraint, used in measurements of √S NN = 200 GeV p+p,d+Au, and Au+Au collisions at the BNL Relativistic Heavy Ionmore » Collider.« less

Spectroscopic (FT-IR and UV-Vis) and theoretical (HF and DFT) investigation of 2-Ethyl-N-[(5-nitrothiophene-2-yl)methylidene]aniline

NASA Astrophysics Data System (ADS)

Ceylan, Ümit; Tarı, Gonca Özdemir; Gökce, Halil; Ağar, Erbil

2016-04-01

Crystal structure of the title compound, 2-Ethyl-N-[(5-nitrothiophene-2-yl)methylidene]aniline, C13H12N2O2S, has been synthesized and characterized by FT-IR and UV-Vis spectrum. The compound crystallized in the monoclinic space group P 21/c with a = 11.3578 (4) Å, b = 7.4923 (2) Å, c = 14.9676 (6) Å and β = 99.589 (3)° and Z = 4 in the unit cell. The molecular geometry was also calculated using the Gaussian 03 software and structure was optimized using the HF and DFT/B3LYP methods with the 6-311++G(d,p) basis set in ground state. Using the TD-DFT method, the electronic absorption spectra of the title compound was computed in both the gas phase and ethanol solvent. The harmonic vibrational frequencies of the title compound were calculated using the same methods with the 6-311++G(d,p) basis set. The calculated results were compared with the experimental determination results of the compound. It was seen that the optimized structure was in excellent agreement with the X-ray crystal structure. The energetic behaviors of the title compound in solvent media were examined using the HF and DFT/B3LYP methods with the 6-311++G(d,p) basis set applying the polarizable continuum model (PCM). In addition, the molecular orbitals (FMOs) analysis, molecular electrostatic potential (MEP), nonlinear optical and thermodynamic properties of the title compound were performed using the same methods with the 6-311++G(d,p) basis set.

Ae2Sb2X4F2 (Ae = Sr, Ba): new members of the homologous series Ae2M(1+n)X(3+n)F2 designed from rock salt and fluorite 2D building blocks.

PubMed

Kabbour, Houria; Cario, Laurent

2006-03-20

We have designed new compounds within the homologous series Ae2F2M(1+n)X(3+n) (Ae = Sr, Ba; M = main group metal; n = integer) built up from the stacking of 2D building blocks of rock salt and fluorite types. By incrementally increasing the size of the rock salt 2D building blocks, we have obtained two new n = 1 members of this homologous series, namely, Sr2F2Sb2Se4 and Ba2F2Sb2Se4. We then succeeded in synthesizing these compounds using a high-temperature ceramic method. The structure refinements from the powder or single-crystal X-ray diffraction data confirmed presence of the expected alternating stacking of fluorite [Ae2F2] (Ae = Sr, Ba) and rock salt [Sb2Se4] 2D building blocks. However the Ba derivative shows a strong distortion of the [Sb2Se4] block and a concomitant change of the Sb atom coordination likely related to the lone-pair activity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Xin; Qiao, Weiye; Li, Yuliang

The structure stabilities and electronic properties are investigated by using ab initio self-consistent-field crystal orbital method based on density functional theory for the one-dimensional (1D) double-wall nanotubes made of n-gon SiO{sub 2} nanotubes encapsulated inside zigzag carbon nanotubes. It is found that formation of the combined systems is energetically favorable when the distance between the two constituents is around the Van der Waals scope. The obtained band structures show that all the combined systems are semiconductors with nonzero energy gaps. The frontier energy bands (the highest occupied band and the lowest unoccupied band) of double-wall nanotubes are mainly derived frommore » the corresponding carbon nanotubes. The mobilities of charge carriers are calculated to be within the range of 10{sup 2}–10{sup 4} cm{sup 2} V{sup −1} s{sup −1} for the hybrid double-wall nanotubes. Young’s moduli are also calculated for the combined systems. For the comparison, geometrical and electronic properties of n-gon SiO{sub 2} nanotubes are also calculated and discussed. - Graphical abstract: Structures and band structures of the optimum 1D Double walls nanotubes. The optimized structures are 3-gon SiO2@(15,0), 5-gon SiO2@(17,0), 6-gon SiO2@(18,0) and 7-gon SiO2@(19,0). - Highlights: • The structure and electronic properties of the 1D n-gon SiO{sub 2}@(m,0)s are studied using SCF-CO method. • The encapsulation of 1D n-gon SiO{sub 2} tubes inside zigzag carbon nanotubes can be energetically favorable. • The 1D n-gon SiO{sub 2}@(m,0)s are all semiconductors. • The mobility of charge carriers and Young’s moduli are calculated.« less

The Statistical Nature of Fatigue Crack Propagation

DTIC Science & Technology

1977-03-01

LEVEL x - V AFFDL-TRt-T843 r THE STATISTICAL NATURE OF b FATIGUE CRACK PROPAGATION D. A. VIRKLER B. M. HILLBERR Y LL= P. K. GOEL C* SCHOOL...function of crack length was best represented by the three-parameter log-normal distribution. Six growth rate calculation methods were investigated and the...dN, which varied moderately as a function of crack length, replicate a vs. N data were predicted This predicted data reproduced the mean behavior but

Fast Geometric Consensus Approach for Protein Model Quality Assessment

PubMed Central

Adamczak, Rafal; Pillardy, Jaroslaw; Vallat, Brinda K.

2011-01-01

Abstract Model quality assessment (MQA) is an integral part of protein structure prediction methods that typically generate multiple candidate models. The challenge lies in ranking and selecting the best models using a variety of physical, knowledge-based, and geometric consensus (GC)-based scoring functions. In particular, 3D-Jury and related GC methods assume that well-predicted (sub-)structures are more likely to occur frequently in a population of candidate models, compared to incorrectly folded fragments. While this approach is very successful in the context of diversified sets of models, identifying similar substructures is computationally expensive since all pairs of models need to be superimposed using MaxSub or related heuristics for structure-to-structure alignment. Here, we consider a fast alternative, in which structural similarity is assessed using 1D profiles, e.g., consisting of relative solvent accessibilities and secondary structures of equivalent amino acid residues in the respective models. We show that the new approach, dubbed 1D-Jury, allows to implicitly compare and rank N models in O(N) time, as opposed to quadratic complexity of 3D-Jury and related clustering-based methods. In addition, 1D-Jury avoids computationally expensive 3D superposition of pairs of models. At the same time, structural similarity scores based on 1D profiles are shown to correlate strongly with those obtained using MaxSub. In terms of the ability to select the best models as top candidates 1D-Jury performs on par with other GC methods. Other potential applications of the new approach, including fast clustering of large numbers of intermediate structures generated by folding simulations, are discussed as well. PMID:21244273

Unveiling the Gamma-Ray Source Count Distribution Below the Fermi Detection Limit with Photon Statistics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zechlin, Hannes-S.; Cuoco, Alessandro; Donato, Fiorenza

The source-count distribution as a function of their flux, dN/dS, is one of the main quantities characterizing gamma-ray source populations. In this paper, we employ statistical properties of the Fermi Large Area Telescope (LAT) photon counts map to measure the composition of the extragalactic gamma-ray sky at high latitudes (|b| greater-than or slanted equal to 30°) between 1 and 10 GeV. We present a new method, generalizing the use of standard pixel-count statistics, to decompose the total observed gamma-ray emission into (a) point-source contributions, (b) the Galactic foreground contribution, and (c) a truly diffuse isotropic background contribution. Using the 6more » yr Fermi-LAT data set (P7REP), we show that the dN/dS distribution in the regime of so far undetected point sources can be consistently described with a power law with an index between 1.9 and 2.0. We measure dN/dS down to an integral flux of ~2 x 10 -11cm -2s -1, improving beyond the 3FGL catalog detection limit by about one order of magnitude. The overall dN/dS distribution is consistent with a broken power law, with a break at 2.1 +1.0 -1.3 x 10 -8cm -2s -1. The power-law index n 1 = 3.1 +0.7 -0.5 for bright sources above the break hardens to n 2 = 1.97 ± 0.03 for fainter sources below the break. A possible second break of the dN/dS distribution is constrained to be at fluxes below 6.4 x 10 -11cm -2s -1 at 95% confidence level. Finally, the high-latitude gamma-ray sky between 1 and 10 GeV is shown to be composed of ~25% point sources, ~69.3% diffuse Galactic foreground emission, and ~6% isotropic diffuse background.« less

Mechanistic Investigation of the Bypass of a Bulky Aromatic DNA Adduct Catalyzed by a Y-family DNA Polymerase

PubMed Central

Gadkari, Varun V.; Tokarsky, E. John; Malik, Chanchal K.; Basu, Ashis K.; Suo, Zucai

2014-01-01

3-Nitrobenzanthrone (3-NBA), a nitropolyaromatic hydrocarbon (NitroPAH) pollutant in diesel exhaust, is a potent mutagen and carcinogen. After metabolic activation, the primary metabolites of 3-NBA react with DNA to form dG and dA adducts. One of the three major adducts identified is N-(2’-deoxyguanosin-8-yl)-3-aminobenzanthrone (dGC8-N-ABA). This bulky adduct likely stalls replicative DNA polymerases but can be traversed by lesion bypass polymerases in vivo. Here, we employed running start assays to show that a site-specifically placed dGC8-N-ABA is bypassed in vitro by Sulfolobus solfataricus DNA polymerase IV (Dpo4), a model Y-family DNA polymerase. However, the nucleotide incorporation rate of Dpo4 was significantly reduced opposite both the lesion and the template position immediately downstream from the lesion site, leading to two strong pause sites. To investigate the kinetic effect of dGC8-N-ABA on polymerization, we utilized pre-steady-state kinetic methods to determine the kinetic parameters for individual nucleotide incorporations upstream, opposite, and downstream from the dGC8-N-ABA lesion. Relative to the replication of the corresponding undamaged DNA template, both nucleotide incorporation efficiency and fidelity of Dpo4 were considerably decreased during dGC8-N-ABA lesion bypass and the subsequent extension step. The lower nucleotide incorporation efficiency caused by the lesion is a result of a significantly reduced dNTP incorporation rate constant and modestly weaker dNTP binding affinity. At both pause sites, nucleotide incorporation followed biphasic kinetics with a fast and a slow phase and their rates varied with nucleotide concentration. In contrast, only the fast phase was observed with undamaged DNA. A kinetic mechanism was proposed for the bypass of dGC8-N-ABA bypass catalyzed by Dpo4. PMID:25048879

Unveiling the Gamma-Ray Source Count Distribution Below the Fermi Detection Limit with Photon Statistics

DOE PAGES

Zechlin, Hannes-S.; Cuoco, Alessandro; Donato, Fiorenza; ...

2016-07-26

The source-count distribution as a function of their flux, dN/dS, is one of the main quantities characterizing gamma-ray source populations. In this paper, we employ statistical properties of the Fermi Large Area Telescope (LAT) photon counts map to measure the composition of the extragalactic gamma-ray sky at high latitudes (|b| greater-than or slanted equal to 30°) between 1 and 10 GeV. We present a new method, generalizing the use of standard pixel-count statistics, to decompose the total observed gamma-ray emission into (a) point-source contributions, (b) the Galactic foreground contribution, and (c) a truly diffuse isotropic background contribution. Using the 6more » yr Fermi-LAT data set (P7REP), we show that the dN/dS distribution in the regime of so far undetected point sources can be consistently described with a power law with an index between 1.9 and 2.0. We measure dN/dS down to an integral flux of ~2 x 10 -11cm -2s -1, improving beyond the 3FGL catalog detection limit by about one order of magnitude. The overall dN/dS distribution is consistent with a broken power law, with a break at 2.1 +1.0 -1.3 x 10 -8cm -2s -1. The power-law index n 1 = 3.1 +0.7 -0.5 for bright sources above the break hardens to n 2 = 1.97 ± 0.03 for fainter sources below the break. A possible second break of the dN/dS distribution is constrained to be at fluxes below 6.4 x 10 -11cm -2s -1 at 95% confidence level. Finally, the high-latitude gamma-ray sky between 1 and 10 GeV is shown to be composed of ~25% point sources, ~69.3% diffuse Galactic foreground emission, and ~6% isotropic diffuse background.« less

Mechanistic investigation of the bypass of a bulky aromatic DNA adduct catalyzed by a Y-family DNA polymerase.

PubMed

Gadkari, Varun V; Tokarsky, E John; Malik, Chanchal K; Basu, Ashis K; Suo, Zucai

2014-09-01

3-Nitrobenzanthrone (3-NBA), a nitropolyaromatic hydrocarbon (NitroPAH) pollutant in diesel exhaust, is a potent mutagen and carcinogen. After metabolic activation, the primary metabolites of 3-NBA react with DNA to form dG and dA adducts. One of the three major adducts identified is N-(2'-deoxyguanosin-8-yl)-3-aminobenzanthrone (dG(C8-N-ABA)). This bulky adduct likely stalls replicative DNA polymerases but can be traversed by lesion bypass polymerases in vivo. Here, we employed running start assays to show that a site-specifically placed dG(C8-N-ABA) is bypassed in vitro by Sulfolobus solfataricus DNA polymerase IV (Dpo4), a model Y-family DNA polymerase. However, the nucleotide incorporation rate of Dpo4 was significantly reduced opposite both the lesion and the template position immediately downstream from the lesion site, leading to two strong pause sites. To investigate the kinetic effect of dG(C8-N-ABA) on polymerization, we utilized pre-steady-state kinetic methods to determine the kinetic parameters for individual nucleotide incorporations upstream, opposite, and downstream from the dG(C8-N-ABA) lesion. Relative to the replication of the corresponding undamaged DNA template, both nucleotide incorporation efficiency and fidelity of Dpo4 were considerably decreased during dG(C8-N-ABA) lesion bypass and the subsequent extension step. The lower nucleotide incorporation efficiency caused by the lesion is a result of a significantly reduced dNTP incorporation rate constant and modestly weaker dNTP binding affinity. At both pause sites, nucleotide incorporation followed biphasic kinetics with a fast and a slow phase and their rates varied with nucleotide concentration. In contrast, only the fast phase was observed with undamaged DNA. A kinetic mechanism was proposed for the bypass of dG(C8-N-ABA) bypass catalyzed by Dpo4. Copyright © 2014 Elsevier B.V. All rights reserved.

A Fast Approach to Automatic Detection of Brain Lesions

PubMed Central

Koley, Subhranil; Chakraborty, Chandan; Mainero, Caterina; Fischl, Bruce; Aganj, Iman

2017-01-01

Template matching is a popular approach to computer-aided detection of brain lesions from magnetic resonance (MR) images. The outcomes are often sufficient for localizing lesions and assisting clinicians in diagnosis. However, processing large MR volumes with three-dimensional (3D) templates is demanding in terms of computational resources, hence the importance of the reduction of computational complexity of template matching, particularly in situations in which time is crucial (e.g. emergent stroke). In view of this, we make use of 3D Gaussian templates with varying radii and propose a new method to compute the normalized cross-correlation coefficient as a similarity metric between the MR volume and the template to detect brain lesions. Contrary to the conventional fast Fourier transform (FFT) based approach, whose runtime grows as O(N logN) with the number of voxels, the proposed method computes the cross-correlation in O(N). We show through our experiments that the proposed method outperforms the FFT approach in terms of computational time, and retains comparable accuracy. PMID:29082383

Conformational preferences of DNA following damage by aristolochic acids: Structural and energetic insights into the different mutagenic potential of the ALI and ALII-N(6)-dA adducts.

PubMed

Kathuria, Preetleen; Sharma, Purshotam; Abendong, Minette N; Wetmore, Stacey D

2015-04-21

Aristolochic acids (AAI and AAII), produced by the Aristolochiaceae family of plants, are classified as group I (human) carcinogens by the International Agency for Research on Cancer. These acids are metabolized in cells to yield aristolactams (ALI and ALII, respectively), which further form bulky adducts with the purine nucleobases. Specifically, the adenine lesions are more persistent in cells and have been associated with chronic renal diseases and related carcinogenesis. To understand the structural basis of the nephrotoxicity induced by AAs, the ALI-N(6)-dA and ALII-N(6)-dA lesions are systematically studied using computational methods. Density functional theory calculations indicate that the aristolactam moiety intrinsically prefers a planar conformation with respect to adenine. Nucleoside and nucleotide models suggest that the anti and syn orientations about the glycosidic bond are isoenergetic for both adducts. Molecular dynamics simulations and free energy calculations reveal that the anti base-displaced intercalated conformation is the most stable conformer for both types of AL-N(6)-dA adducted DNA, which agrees with previous experimental work on the ALII-N(6)-dA adduct and thereby validates our approach. Interestingly, this conformer differs from the dominant conformations adopted by other N6-linked adenine lesions, including those derived from polycyclic aromatic hydrocarbons. Furthermore, the second most stable syn base-displaced intercalated conformation lies closer in energy to the anti base-displaced intercalated conformation for ALI-N(6)-dA compared to ALII-N(6)-dA. This indicates that a mixture of conformations may be detectable for ALI-N(6)-dA in DNA. If this enhanced conformational flexibility of double-stranded DNA persists when bound to a lesion-bypass polymerase, this provides a possible structural explanation for the previously observed greater nephrotoxic potential for the ALI versus ALII-N(6)-dA adduct. In addition, the structural characteristics of the preferred conformations of adducted DNA explain the resistance of these adducts to repair and thereby add to our current understanding of the toxicity of AAs within living cells.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bleiziffer, Patrick, E-mail: patrick.bleiziffer@fau.de; Krug, Marcel; Görling, Andreas

A self-consistent Kohn-Sham method based on the adiabatic-connection fluctuation-dissipation (ACFD) theorem, employing the frequency-dependent exact exchange kernel f{sub x} is presented. The resulting SC-exact-exchange-only (EXX)-ACFD method leads to even more accurate correlation potentials than those obtained within the direct random phase approximation (dRPA). In contrast to dRPA methods, not only the Coulomb kernel but also the exact exchange kernel f{sub x} is taken into account in the EXX-ACFD correlation which results in a method that, unlike dRPA methods, is free of self-correlations, i.e., a method that treats exactly all one-electron systems, like, e.g., the hydrogen atom. The self-consistent evaluation ofmore » EXX-ACFD total energies improves the accuracy compared to EXX-ACFD total energies evaluated non-self-consistently with EXX or dRPA orbitals and eigenvalues. Reaction energies of a set of small molecules, for which highly accurate experimental reference data are available, are calculated and compared to quantum chemistry methods like Møller-Plesset perturbation theory of second order (MP2) or coupled cluster methods [CCSD, coupled cluster singles, doubles, and perturbative triples (CCSD(T))]. Moreover, we compare our methods to other ACFD variants like dRPA combined with perturbative corrections such as the second order screened exchange corrections or a renormalized singles correction. Similarly, the performance of our EXX-ACFD methods is investigated for the non-covalently bonded dimers of the S22 reference set and for potential energy curves of noble gas, water, and benzene dimers. The computational effort of the SC-EXX-ACFD method exhibits the same scaling of N{sup 5} with respect to the system size N as the non-self-consistent evaluation of only the EXX-ACFD correlation energy; however, the prefactor increases significantly. Reaction energies from the SC-EXX-ACFD method deviate quite little from EXX-ACFD energies obtained non-self-consistently with dRPA orbitals and eigenvalues, and the deviation reduces even further if the Coulomb kernel is scaled by a factor of 0.75 in the dRPA to reduce self-correlations in the dRPA correlation potential. For larger systems, such a non-self-consistent EXX-ACFD method is a competitive alternative to high-level wave-function-based methods, yielding higher accuracy than MP2 and CCSD methods while exhibiting a better scaling of the computational effort than CCSD or CCSD(T) methods. Moreover, EXX-ACFD methods were shown to be applicable in situation characterized by static correlation.« less

Identification of N-(deoxyguanosin-8-yl)-4-azobiphenyl by (32)P-postlabeling analyses of DNA in human uroepithelial cells exposed to proximate metabolites of the environmental carcinogen 4-aminobiphenyl.

PubMed

Hatcher, James F; Swaminathan, Santhanam

2002-01-01

DNA adducts formed in human uroepithelial cells (HUC) following exposure to N-hydroxy-4-aminobiphenyl (N-OH-ABP), the proximate metabolite of the human bladder carcinogen 4-aminobiphenyl (ABP), were analyzed by the (32)P-postlabeling method. Two adducts detected by (32)P-postlabeling were previously identified as the 3',5'-bisphospho derivatives of N-(deoxyguanosin-8-yl)-4-aminobiphenyl (dG-C8-ABP) and N-(deoxyadenosin-8-yl)-4-aminobiphenyl (dA-C8-ABP) (Frederickson S et al. [1992] Carcinogenesis 13: 955-961; Hatcher and Swaminathan [1995b] Carcinogenesis 16: 295-301). In contrast to the dG-C8-ABP adduct, which was 3'-dephosphorylated by nuclease P1, dA-C8-ABP was resistant to nuclease P1, thus providing an enrichment step before postlabeling. Autoradiography of the two-dimensional thin-layer chromatogram of the postlabeled products obtained following nuclease P1 digestion revealed several minor adducts, one of which has been identified in the present study. Postlabeling analyses following nuclease P1 digestion of the products obtained from the reaction of N-acetoxy-4-aminobiphenyl with deoxyguanosine-3'-monophosphate (dGp) demonstrated the presence of this minor adduct. The 3'-monophosphate derivative of the adduct was subsequently chromatographically purified and subjected to spectroscopic analyses. Based on proton NMR and mass spectroscopic analyses of the synthetic product, the chemical structure of the adduct has been identified as N-(deoxyguanosin-N(2)-yl)-4-azobiphenyl (dG-N==N-ABP). (32)P-Postlabeling analysis of the nuclease P1-enriched DNA hydrolysate of HUCs treated with N-OH-ABP or N-hydroxy-4-acetylaminobiphenyl (N-OH-AABP) showed the presence of the dG-N==N-ABP adduct. It was also detected in calf thymus DNA incubated with HUC cytosol and N-OH-ABP in the presence of acetyl-CoA, or incubated with HUC microsomes and N-OH-AABP. These results demonstrate that in the target cells for ABP carcinogenesis in vivo, N-OH-ABP and N-OH-AABP are bioactivated by acyltransferases to reactive arylnitrenium ions that covalently interact at the N2 position of deoxyguanosine in DNA. Copyright 2002 Wiley-Liss, Inc.

Fractional modeling of viscoelasticity in 3D cerebral arteries and aneurysms

PubMed Central

Perdikaris, Paris; Karniadakis, George Em

2017-01-01

We develop efficient numerical methods for fractional order PDEs, and employ them to investigate viscoelastic constitutive laws for arterial wall mechanics. Recent simulations using one-dimensional models [1] have indicated that fractional order models may offer a more powerful alternative for modeling the arterial wall response, exhibiting reduced sensitivity to parametric uncertainties compared with the integer-calculus-based models. Here, we study three-dimensional (3D) fractional PDEs that naturally model the continuous relaxation properties of soft tissue, and for the first time employ them to simulate flow structure interactions for patient-specific brain aneurysms. To deal with the high memory requirements and in order to accelerate the numerical evaluation of hereditary integrals, we employ a fast convolution method [2] that reduces the memory cost to O(log(N)) and the computational complexity to O(N log(N)). Furthermore, we combine the fast convolution with high-order backward differentiation to achieve third-order time integration accuracy. We confirm that in 3D viscoelastic simulations, the integer order models strongly depends on the relaxation parameters, while the fractional order models are less sensitive. As an application to long-time simulations in complex geometries, we also apply the method to modeling fluid–structure interaction of a 3D patient-specific compliant cerebral artery with an aneurysm. Taken together, our findings demonstrate that fractional calculus can be employed effectively in modeling complex behavior of materials in realistic 3D time-dependent problems if properly designed efficient algorithms are employed to overcome the extra memory requirements and computational complexity associated with the non-local character of fractional derivatives. PMID:29104310

Binding affinities of NKG2D and CD94 to sialyl Lewis X-expressing N-glycans and heparin.

PubMed

Higai, Koji; Suzuki, Chiho; Imaizumi, Yuzo; Xin, Xin; Azuma, Yutaro; Matsumoto, Kojiro

2011-01-01

Lectin-like receptors natural killer group 2D (NKG2D) and CD94 on natural killer (NK) cells bind to α2,3-NeuAc-containing N-glycans and heparin/heparan sulfate (HS). Using recombinant glutathione S-transferase-fused extracellular lectin-like domains of NKG2D (rGST-NKG2Dlec) and CD94 (rGST-CD94lec), we evaluated their binding affinities (K(d)) to high sialyl Lewis X (sLeX)-expressing transferrin secreted by HepG2 cells (HepTf) and heparin-conjugated bovine serum albumin (Heparin-BSA), using quartz crystal microbalance (QCM) and enzyme immunoassay (EIA) microplate methods. K(d) values obtained by linear reciprocal plots revealed good coincidence between the two methods. K(d) values of rGST-NKG2Dlec obtained by QCM and EIA, respectively, were 1.19 and 1.11 µM for heparin-BSA >0.30 and 0.20 µM for HepTf, while those of rGST-CD94lec were 1.31 and 1.45 µM for HepTf >0.37 and 0.36 µM for heparin-BSA. These results suggested that these glycans can interact with NKG2D and CD94 to modulate NK cell-dependent cytotoxicity.

Testing tail-mounted transmitters with Myocastor coypus (nutria)

USGS Publications Warehouse

Merino, S.; Carter, J.; Thibodeaux, G.

2007-01-01

We developed a tail-mounted radio-transmitter for Myocastor coypus (nutria) that offers a practical and efficient alternative to collar or implant methods. The mean retention time was 96 d (range 57-147 d, n = 7), making this a practical method for short-term studies. The tail-mounts were less injurious to animals than collars and easier for field researchers to implement than either collars or surgically implanted transmitters.

Unified Method for Delay Analysis of Random Multiple Access Algorithms.

DTIC Science & Technology

1985-08-01

packets in the first cell of the stack. The rules of the algorithm yield the following relation for the wi’s: n-1 n w 0= ; W =1; i i 9Q h I+ + zwI .+N...for computer communica- tions", in Proc. 1970 Fall Joint Computer Conf., AFIPS Press, vol. 37, 1970, pp. 281 -285. (15] N. D. Vvedenskaya and B. S

An efficient synthesis method targeted to a novel aziridine derivative of p-menthane from turpentine and its herbicidal activity.

PubMed

Zhu, Shou-Ji; Xu, Shi-Chao; Zhao, Zhen-Dong

2017-07-01

A novel aziridine compound N-acetyl-1,2-azacyclo-p-menthane d was synthesised using turpentine as raw material and characterised by FT-IR, 1 H NMR, 13 C NMR, ESI + -MS and HRMS. The pre-emergence herbicidal activities of d and its synthetic intermediates cis- and trans-N,N'-diacetyl-p-menthane-1,8-diamine (b2 and b1) were determined. The result showed that d exhibited much higher herbicidal activities against annual ryegrass, Digitaria sanguinalis and Ixeris denticulate than b2 and b1. The IC 50 of d against the root and shoot growth of these three plants were lower than 1 mmol L -1 . In contrast, the IC 50 of b1 and b2 against the root and shoot growth of these plants were more than 10 mmol L -1 .

[Laser in situ keratomyleusis (LASIK) for correction of myopia and hypermetropia--our one year experience].

PubMed

Vukosavljević, Miroslav; Milivojević, Milorad; Resan, Mirko; Cerović, Vesna

2009-12-01

Laser in situ keratamileusis (LASIK) is the most commonly used refractive surgical method worldwide. The aim of this study was to examine the effectiveness and safety of LASIK in the correction of myopia and hyperopia. The study included myopic and hyperopic eyes with preoperative best corrected visual acuity (BCVA) = 1 (20/20), of the total number of 322 divided into 2 groups--1) myopic eyes (n = 241) which were divided into 4 subgroups according to the myopia strength: a) < or = -1.75 D (n = 23), b) from -2 to -3.75 D (n = 81), c) from -4 to -6.75 D (n = 113), d) > or = -7 D (n = 24); 2) hyperopic eyes (n = 81) which were divided into 3 subgroups according to the hyperopia strength: a) < or = +1.75D (n = 10), b) from +2 to +3.75 D (n = 46), c) > or = +4 D (n = 25). Myopic and hyperopic eyes with preoperative BCVA < or = 0.9 (eyes with ambliopia) were excluded from the study, as well as eyes with astigmatism > 1.5 D. To assess the effectiveness of LASIK we examined the percentage of eyes in the mentioned subgroups, which derived uncorrected visual acuity (UCVA) 6 month after the intervention to the following: a) UCVA = 1 (20/20) and b) UCVA > or = 0.5 (20/40). To assess the safety of LASIK we examined the frequency of intraoperative and postoperative complications. A prospective study was performed in a 6-months follow-up period. RESULTS. Refractive spherical equivalent (RSE) of myopic eyes was in the range from -0.75 D to -12 D. In the first subgroup preoperative mean value of RSE with standard deviation (mean RSE +/- SD) was -1.39 +/- 0.36 D, and 6 months after the LASIK 100% of the eyes had UCVA = 20/20. In the second subgroup preoperative mean RSE +/- SD was -2.85 +/- 0.50 D, and 6 months after LASIK 93% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA > or = 20/40. In the third subgroup preoperative mean RSE +/- SD was -5.03 +/- 0.75 D, and 6 months after the LASIK 90% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA > or = 20/40. In the fourth subgroup preoperative mean RSE +/- SD was -7.68 +/- 1.03 D, and 6 months after the LASIK 96% of the eyes had UCVA = 20/20, but 100% of eyes had UCVA > or = 20/40. Refractive spherical equivalent of hyperopic eyes was in the range from +1 D to +6 D. In the first subgroup preoperative mean RSE +/- SD was +1.50 +/- 0.30 D, and 6 months after the LASIK 90% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA > or = 20/40. In the second subgroup preoperative mean RSE +/- SD was +2.65 +/- 0.46 D, and 6 months after the LASIK 87% of the eyes had UCVA = 20/20, but 96% of the eyes had UCVA > or = 20/40. In the third subgroup preoperative mean RSE +/- SD was +4.62 +/- 0.68 D, and 6 months after the LASIK 64% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA > or = 20/40. In our study intraoperative complications appeared in 6 eyes (1.86%): thin flap in 2 eyes (0.62%) and epithelial defects in 4 eyes (1.24%), yet postoperative complications appeared in 10 eyes (3.10%): flap folds in 2 eyes (0.62%), epithelial ingrowth in 4 eyes (1.24%) and regression in 4 eyes (1.24%). LASIK is effective and safe refractive surgical method for correcting myopia up to -12 D and hyperopia up to +6 D.

Generating high-current monoenergetic proton beams by a circularly polarized laser pulse in the phase-stable acceleration regime.

PubMed

Yan, X Q; Lin, C; Sheng, Z M; Guo, Z Y; Liu, B C; Lu, Y R; Fang, J X; Chen, J E

2008-04-04

A new ion acceleration method, namely, phase-stable acceleration, using circularly-polarized laser pulses is proposed. When the initial target density n(0) and thickness D satisfy a(L) approximately (n(0)/n(c))D/lambda(L) and D>l(s) with a(L), lambda(L), l(s), and n(c) the normalized laser amplitude, the laser wavelength in vacuum, the plasma skin depth, and the critical density of the incident laser pulse, respectively, a quasiequilibrium for the electrons is established by the light pressure and the space charge electrostatic field at the interacting front of the laser pulse. The ions within the skin depth of the laser pulse are synchronously accelerated and bunched by the electrostatic field, and thereby a high-intensity monoenergetic proton beam can be generated. The proton dynamics is investigated analytically and the results are verified by one- and two-dimensional particle-in-cell simulations.

Manufacturing Methods and Technology Program Plan, CY 1984.

DTIC Science & Technology

1984-09-01

77nD-Al48 828 MANUFACTURING METHODS AIND TECHNOLOGY PROGRAM PLAN CY 1/3 1984(U) ARMY INDUSTRIAL BASE ENGINEERING ACTIVITY ROCK ISLAND IL G FISCHER...1984 MANUFACTURING TECHNOLOGY DIVISION U S ARMY INDUSTRIAL BASE ENGINEERING ACTIVITY ROCK ISLAND, ILLINOIS 61299-7260 8 4 30 033 .. . . . . ...4i.l...NUMBE2N. GOVT ACCESSION NO. 3. RECIPIENT’S CATALOG NUMBER i2- ffl7’ NONE 14TTITLE (Mid Skdde) S. TYPE OF REPORT & PERIOD COVERED MANUFACTURING METHODS

3D galaxy clustering with future wide-field surveys: Advantages of a spherical Fourier-Bessel analysis

NASA Astrophysics Data System (ADS)

Lanusse, F.; Rassat, A.; Starck, J.-L.

2015-06-01

Context. Upcoming spectroscopic galaxy surveys are extremely promising to help in addressing the major challenges of cosmology, in particular in understanding the nature of the dark universe. The strength of these surveys, naturally described in spherical geometry, comes from their unprecedented depth and width, but an optimal extraction of their three-dimensional information is of utmost importance to best constrain the properties of the dark universe. Aims: Although there is theoretical motivation and novel tools to explore these surveys using the 3D spherical Fourier-Bessel (SFB) power spectrum of galaxy number counts Cℓ(k,k'), most survey optimisations and forecasts are based on the tomographic spherical harmonics power spectrum C(ij)_ℓ. The goal of this paper is to perform a new investigation of the information that can be extracted from these two analyses in the context of planned stage IV wide-field galaxy surveys. Methods: We compared tomographic and 3D SFB techniques by comparing the forecast cosmological parameter constraints obtained from a Fisher analysis. The comparison was made possible by careful and coherent treatment of non-linear scales in the two analyses, which makes this study the first to compare 3D SFB and tomographic constraints on an equal footing. Nuisance parameters related to a scale- and redshift-dependent galaxy bias were also included in the computation of the 3D SFB and tomographic power spectra for the first time. Results: Tomographic and 3D SFB methods can recover similar constraints in the absence of systematics. This requires choosing an optimal number of redshift bins for the tomographic analysis, which we computed to be N = 26 for zmed ≃ 0.4, N = 30 for zmed ≃ 1.0, and N = 42 for zmed ≃ 1.7. When marginalising over nuisance parameters related to the galaxy bias, the forecast 3D SFB constraints are less affected by this source of systematics than the tomographic constraints. In addition, the rate of increase of the figure of merit as a function of median redshift is higher for the 3D SFB method than for the 2D tomographic method. Conclusions: Constraints from the 3D SFB analysis are less sensitive to unavoidable systematics stemming from a redshift- and scale-dependent galaxy bias. Even for surveys that are optimised with tomography in mind, a 3D SFB analysis is more powerful. In addition, for survey optimisation, the figure of merit for the 3D SFB method increases more rapidly with redshift, especially at higher redshifts, suggesting that the 3D SFB method should be preferred for designing and analysing future wide-field spectroscopic surveys. CosmicPy, the Python package developed for this paper, is freely available at https://cosmicpy.github.io. Appendices are available in electronic form at http://www.aanda.org

CO2 and soil water potential as regulators of the growth and N fraction derived from fixation of a legume in tallgrass prairie communities

USDA-ARS?s Scientific Manuscript database

CO2 enrichment may increase N input to ecosystems by increasing N2 fixation, but the fixation-CO2 response depends on factors such as soil water availability that are influenced by both CO2 and soil properties. We used the d15N natural abundance method to determine N2 fixation by the legume Desmant...

Novel density functional methodology for the computation of accurate electronic and thermodynamic properties of molecular systems and improved long-range behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kafafi, S.A.

1998-12-10

A novel general purpose density functional methodology for the computation of accurate electronic and thermodynamic properties of molecules and improved long-range behavior is reported. Assuming the separability of the exchange (E{sub x}) and correlation (E{sub c}) contributions to the total exchange-correlation energy functional (E{sub xc}), the E{sub x} term consists of a hybrid mixture of 37.5% Hartree-Fock exchange and the appropriate local spin density exchange using the adiabatic connection formula. He demonstrated that E{sub x} and its corresponding potential V{sub x} [=dE{sub x}/d{rho}(r)] have the proper asymptotic limits at r = 0 and r {r_arrow} {infinity}, E{sub c} consists ofmore » the Vosko, Wilk, and Nusair formula for the free-electron gas correlation energy and a generalized gradient approximation term with one adjustable parameter. V{sub c} [=dE{sub c}/d{rho}(r)] was shown to obey the r {r_arrow} {infinity} limit of the corresponding potential derived from exact atomic exchange-correlation computations; namely, V{sub c} is proportional to r{sup {minus}4}. Most importantly, he demonstrated that, at r values where dispersion forces are operating, V{sub c} is proportional to 1/r{sup n} (n = 4, 6, 8, {hor_ellipsis}). The reported method was denoted by K2-BVWN because it used two adjustable parameters in its formulation. The K2-BVWN scheme scales as N{sup 3}, where N is the number of basis functions, compared to {approximately}N{sup 7} for Gaussian-2 (G2) ab initio theory and related methods, {approximately}N{sup 5} for Barone`s mPW1,3PW, and {approximately}N{sup 4} for Becke`s three-parameter density functional approaches. The G2 data set complemented by the reported molecular systems investigated in this work was recommended as a critical test for evaluating novel ab initio and density functional methodologies. The K2-BVWN method has been implemented in the Gaussian series of programs.« less

Development and validation of spectrophotometric methods for estimating amisulpride in pharmaceutical preparations.

PubMed

Sharma, Sangita; Neog, Madhurjya; Prajapati, Vipul; Patel, Hiren; Dabhi, Dipti

2010-01-01

Five simple, sensitive, accurate and rapid visible spectrophotometric methods (A, B, C, D and E) have been developed for estimating Amisulpride in pharmaceutical preparations. These are based on the diazotization of Amisulpride with sodium nitrite and hydrochloric acid, followed by coupling with N-(1-naphthyl)ethylenediamine dihydrochloride (Method A), diphenylamine (Method B), beta-naphthol in an alkaline medium (Method C), resorcinol in an alkaline medium (Method D) and chromotropic acid in an alkaline medium (Method E) to form a colored chromogen. The absorption maxima, lambda(max), are at 523 nm for Method A, 382 and 490 nm for Method B, 527 nm for Method C, 521 nm for Method D and 486 nm for Method E. Beer's law was obeyed in the concentration range of 2.5-12.5 microg mL(-1) in Method A, 5-25 and 10-50 microg mL(-1) in Method B, 4-20 microg mL(-1) in Method C, 2.5-12.5 microg mL(-1) in Method D and 5-15 microg mL(-1) in Method E. The results obtained for the proposed methods are in good agreement with labeled amounts, when marketed pharmaceutical preparations were analyzed.

Three-dimensional Visualization of Ultrasound Backscatter Statistics by Window-modulated Compounding Nakagami Imaging.

PubMed

Zhou, Zhuhuang; Wu, Shuicai; Lin, Man-Yen; Fang, Jui; Liu, Hao-Li; Tsui, Po-Hsiang

2018-05-01

In this study, the window-modulated compounding (WMC) technique was integrated into three-dimensional (3D) ultrasound Nakagami imaging for improving the spatial visualization of backscatter statistics. A 3D WMC Nakagami image was produced by summing and averaging a number of 3D Nakagami images (number of frames denoted as N) formed using sliding cubes with varying side lengths ranging from 1 to N times the transducer pulse. To evaluate the performance of the proposed 3D WMC Nakagami imaging method, agar phantoms with scatterer concentrations ranging from 2 to 64 scatterers/mm 3 were made, and six stages of fatty liver (zero, one, two, four, six, and eight weeks) were induced in rats by methionine-choline-deficient diets (three rats for each stage, total n = 18). A mechanical scanning system with a 5-MHz focused single-element transducer was used for ultrasound radiofrequency data acquisition. The experimental results showed that 3D WMC Nakagami imaging was able to characterize different scatterer concentrations. Backscatter statistics were visualized with various numbers of frames; N = 5 reduced the estimation error of 3D WMC Nakagami imaging in visualizing the backscatter statistics. Compared with conventional 3D Nakagami imaging, 3D WMC Nakagami imaging improved the image smoothness without significant image resolution degradation, and it can thus be used for describing different stages of fatty liver in rats.

Mean glandular dose coefficients (D(g)N) for x-ray spectra used in contemporary breast imaging systems.

PubMed

Nosratieh, Anita; Hernandez, Andrew; Shen, Sam Z; Yaffe, Martin J; Seibert, J Anthony; Boone, John M

2015-09-21

To develop tables of normalized glandular dose coefficients D(g)N for a range of anode-filter combinations and tube voltages used in contemporary breast imaging systems. Previously published mono-energetic D(g)N values were used with various spectra to mathematically compute D(g)N coefficients. The tungsten anode spectra from TASMICS were used; molybdenum and rhodium anode-spectra were generated using MCNPX Monte Carlo code. The spectra were filtered with various thicknesses of Al, Rh, Mo or Cu. An initial half value layer (HVL) calculation was made using the anode and filter material. A range of the HVL values was produced with the addition of small thicknesses of polymethyl methacrylate (PMMA) as a surrogate for the breast compression paddle, to produce a range of HVL values at each tube voltage. Using a spectral weighting method, D(g)N coefficients for the generated spectra were calculated for breast glandular densities of 0%, 12.5%, 25%, 37.5%, 50% and 100% for a range of compressed breast thicknesses from 3 to 8 cm. Eleven tables of normalized glandular dose (D(g)N) coefficients were produced for the following anode/filter combinations: W + 50 μm Ag, W + 500 μm Al, W + 700 μm Al, W + 200 μm Cu, W + 300 μm Cu, W + 50 μm Rh, Mo + 400 μm Cu, Mo + 30 μm Mo, Mo + 25 μm Rh, Rh + 400 μm Cu and Rh + 25 μm Rh. Where possible, these results were compared to previously published D(g)N values and were found to be on average less than 2% different than previously reported values.Over 200 pages of D(g)N coefficients were computed for modeled x-ray system spectra that are used in a number of new breast imaging applications. The reported values were found to be in excellent agreement when compared to published values.

[Identifying dry-weather flow and pollution load sources of separate storm sewer systems with different degrees of illicit discharge].

PubMed

Meng, Ying-ying; Feng, Cang; Li, Tian; Wang, Ling

2009-12-01

Dry-weather flow quantity and quality of three representative separate storm sewer systems in Shanghai-H, G, N were studied. Based on survey of operating status of the pumping stations as well as characteristics of the drainage systems, it was obtained that the interception sewage volumes per unit area in the three systems were 3610 m3/(km2 x d), 1550 m3/(km2 x d), 2970 m3/(km2 x d) respectively; the sanitary wastewater included accounted for 25%, 85% and 71% respectively; the interception volume of H was mainly composed of infiltrated underground water, so the dry-weather flow pollution was slighter, and the interception volumes of G, N were both mainly composed of sanitary wastewater, so the dry-weather which were flow pollution was relatively serious. The water characteristics of potential illicit discharge sources of dry-weather which were flow-grey water, black water and underground water were preliminarily explored, so that treating three parameters-LAS/ NH4+ -N, NH4+ -N/K, Mg/K as tracer parameters of grey water, black water and underground water was put forward. Moreover, the water characteristics of grey water and sanitary wastewater including black water were summarized: the feature of grey water was LAS/NH4+ -N > 0.2, NH4+ -N/K <1, and sanitary wastewater was LAS/NH4+ -N < 0.2, NH4+ -N/K >1. Based on the above, the applications of flow chart method and CMBM method in dry-weather flow detection of monitored storm systems were preliminarily discussed, and the results were basically same as that obtained in flow quantity and quality comprehensive analysis. The research results and methods can provide guidance for analysis and diagnosis of dry-weather flow sources and subsequent reconstruction projects in similar separate storm sewer systems at home.

Fisher zeros and conformality in lattice models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meurice, Yannick; Bazavov, Alexei; Berg, Bernd A.

2012-10-01

Fisher zeros are the zeros of the partition function in the complex beta=2N_c/g^2 plane. When they pinch the real axis, finite size scaling allows one to distinguish between first and second order transition and to estimate exponents. On the other hand, a gap signals confinement and the method can be used to explore the boundary of the conformal window. We present recent numerical results for 2D O(N) sigma models, 4D U(1) and SU(2) pure gauge and SU(3) gauge theory with N_f=4 and 12 flavors. We discuss attempts to understand some of these results using analytical methods. We discuss the 2-latticemore » matching and qualitative aspects of the renormalization group (RG) flows in the Migdal-Kadanoff approximation, in particular how RG flows starting at large beta seem to move around regions where bulk transitions occur. We consider the effects of the boundary conditions on the nonperturbative part of the average energy and on the Fisher zeros for the 1D O(2) model.« less

Analysis of optical purity and impurity of synthetic D-phenylalanine products using sulfated beta-cyclodextrin as chiral selector by reversed-polarity capillary electrophoresis.

PubMed

Zhao, Yan; Yang, Xing-Bin; Jiang, Ru; Sun, Xiao-Li; Li, Xiao-Ye; Liu, Wen-Min; Zhang, Sheng-Yong

2006-02-01

A new capillary electrophoresis (CE) method has been achieved for simultaneous separation and quantification of phenylalanine, N-acetylphenylalanine enantiomers, and prochiral N-acetylaminocinnamic acid, possibly co-existent in reaction systems or synthesized products of D-phenylalanine. The separation was carried out in an uncoated capillary under reversed-electrophoretic mode. Among the diverse charged cyclodextrins (CDs) examined, highly sulfated (HS)-beta-CD as the chiral selector exhibited the best enantioselectivity. The complete separation of the analytes was obtained under the optimum conditions of pH 2.5, 35 mM Tris buffer containing 4% HS-beta-CD, applied voltage -15 kV, and capillary temperature 25 degrees C. Furthermore, the proposed method was applied to the determination of optical purity and trace impurities in three batches of the asymmetric synthetic samples of D-phenylalanine, and satisfactory results were obtained. The determination recoveries of the samples were in the range of 97.8-103.8%, and precisions fell within 2.3-5.0% (RSD). The results demonstrate that this CE method is a useful, simple technique and is applicable to purity assays of D-phenylalanine. (c) 2005 Wiley-Liss, Inc.

Three-dimensional scene reconstruction from a two-dimensional image

NASA Astrophysics Data System (ADS)

Parkins, Franz; Jacobs, Eddie

2017-05-01

We propose and simulate a method of reconstructing a three-dimensional scene from a two-dimensional image for developing and augmenting world models for autonomous navigation. This is an extension of the Perspective-n-Point (PnP) method which uses a sampling of the 3D scene, 2D image point parings, and Random Sampling Consensus (RANSAC) to infer the pose of the object and produce a 3D mesh of the original scene. Using object recognition and segmentation, we simulate the implementation on a scene of 3D objects with an eye to implementation on embeddable hardware. The final solution will be deployed on the NVIDIA Tegra platform.

Temperature Profiles of Different Cooling Methods in Porcine Pancreas Procurement

PubMed Central

Weegman, Brad P.; Suszynski, Thomas M.; Scott, William E.; Ferrer, Joana; Avgoustiniatos, Efstathios S.; Anazawa, Takayuki; O’Brien, Timothy D.; Rizzari, Michael D.; Karatzas, Theodore; Jie, Tun; Sutherland, David ER.; Hering, Bernhard J.; Papas, Klearchos K.

2014-01-01

Background Porcine islet xenotransplantation is a promising alternative to human islet allotransplantation. Porcine pancreas cooling needs to be optimized to reduce the warm ischemia time (WIT) following donation after cardiac death, which is associated with poorer islet isolation outcomes. Methods This study examines the effect of 4 different cooling Methods on core porcine pancreas temperature (n=24) and histopathology (n=16). All Methods involved surface cooling with crushed ice and chilled irrigation. Method A, which is the standard for porcine pancreas procurement, used only surface cooling. Method B involved an intravascular flush with cold solution through the pancreas arterial system. Method C involved an intraductal infusion with cold solution through the major pancreatic duct, and Method D combined all 3 cooling Methods. Results Surface cooling alone (Method A) gradually decreased core pancreas temperature to < 10 °C after 30 minutes. Using an intravascular flush (Method B) improved cooling during the entire duration of procurement, but incorporating an intraductal infusion (Method C) rapidly reduced core temperature 15–20 °C within the first 2 minutes of cooling. Combining all methods (Method D) was the most effective at rapidly reducing temperature and providing sustained cooling throughout the duration of procurement, although the recorded WIT was not different between Methods (p=0.36). Histological scores were different between the cooling Methods (p=0.02) and the worst with Method A. There were differences in histological scores between Methods A and C (p=0.02) and Methods A and D (p=0.02), but not between Methods C and D (p=0.95), which may highlight the importance of early cooling using an intraductal infusion. Conclusions In conclusion, surface cooling alone cannot rapidly cool large (porcine or human) pancreata. Additional cooling with an intravascular flush and intraductal infusion results in improved core porcine pancreas temperature profiles during procurement and histopathology scores. These data may also have implications on human pancreas procurement since use of an intraductal infusion is not common practice. PMID:25040217

PET Imaging of D2/3 agonist binding in healthy human subjects with the radiotracer [11C]-N-propyl-nor-apomorphine (NPA): preliminary evaluation and reproducibility studies

PubMed Central

Narendran, Rajesh; Frankle, W. Gordon; Mason, N. Scott; Laymon, Charles M.; Lopresti, Brian J; Price, Julie C.; Kendro, Steve; Vora, Shivangi; Litschge, Maralee; Mountz, James M.; Mathis, Chester A.

2009-01-01

Objective (-)-N-[11C]-Propyl-norapomorphine (NPA) is a full dopamine D2/3 receptor agonist radiotracer suitable for imaging D2/3 receptors configured in a state of high affinity for agonists using Positron Emission Tomography (PET). The aim of the present study was to define the optimal analytic method to derive accurate and reliable D2/3 receptor parameters with [11C]NPA. Methods Six healthy subjects (4 females/2 males) underwent two [11C]NPA scans in the same day. D2/3 receptor binding parameters were estimated using kinetic analysis (using 1- and 2- tissue compartment models) as well as simplified reference tissue method in the three functional subdivisions of the striatum (associative striatum, AST; limbic striatum LST and sensorimotor striatum SMST). The test-retest variability and intraclass correlation coefficient were assessed for distribution volume (VT), binding potential relative to plasma concentration (BPP), and binding potential relative to nondisplaceable uptake (BPND) Results A two-tissue compartment kinetic model adequately described the functional subdivisions of the striatum as well as cerebellum time-activity data. The reproducibility of VT was excellent (≤ 10%) in all regions, for this approach. The reproducibility of both BPP (≤ 12%) and BPND (≤ 10%) was also excellent. The intraclass correlation coefficient of BPP and BPND were acceptable as well (> 0.75) in the three functional subdivisions of the striatum. Although SRTM led to an underestimation of BPND values relative to that estimated by kinetic analysis by 8 to 13%, the values derived using both the methods were reasonably well correlated (r2 = 0.89, n = 84). Both methods were similarly effective at detecting the differences in [11C]NPA BPND between subjects. Conclusion The results of this study indicate that [11C]NPA can be used to measure D2/3 receptors configured in a state of high affinity for the agonists with high reliability and reproducibility in the functional subdivisions of the human striatum. PMID:19301416

Variational description of the positive column with two-stem ionization

NASA Technical Reports Server (NTRS)

Crawford, F. W.

1979-01-01

The ionization balance in diffusion dominated discharges which depends on both one and two step ionization processes is considered. The Spenke diffusion equation (D sq delta n + neutrino n + sq kn =0) describing such conditions is solved by the Rayleigh-Ritz variational method. Simple analytic approximations to the density profile, and the similarity relation between neutrino,k,D and the discharge dimensions, are derived for planar and cylindrical geometry, and compared with exact computations for certain limiting cases.

Collected Papers 1955-1970, M. D. Parrish, M.D. Colonel Medical Corps US Army (RET),

DTIC Science & Technology

1981-01-01

has been de- veloped by government. The group strengthens families and neighborhoods, and de- velops racial pride without violence . It does similar...and useful methods of group treatmenit had Lo die, at least temporarily. 62. The Use of Existential Conccpt -s -_i n _ (._oii lh!ra’!,py2jiId Tra in i n...and ,,ods h effect mood changes are seen as the basis of most modern economics; for ex- ample, drugs, food, sex, violence , entertainment, work

Equiangular tight frames and unistochastic matrices

NASA Astrophysics Data System (ADS)

Goyeneche, Dardo; Turek, Ondřej

2017-06-01

We demonstrate that a complex equiangular tight frame composed of N vectors in dimension d, denoted ETF (d, N), exists if and only if a certain bistochastic matrix, univocally determined by N and d, belongs to a special class of unistochastic matrices. This connection allows us to find new complex ETFs in infinitely many dimensions and to derive a method to introduce non-trivial free parameters in ETFs. We present an explicit six-parametric family of complex ETF(6,16), which defines a family of symmetric POVMs. Minimal and maximal possible average entanglement of the vectors within this qubit-qutrit family are described. Furthermore, we propose an efficient numerical procedure to compute the unitary matrix underlying a unistochastic matrix, which we apply to find all existing classes of complex ETFs containing up to 20 vectors.

Global linear gyrokinetic simulation of energetic particle-driven instabilities in the LHD stellarator

DOE PAGES

Spong, Donald A.; Holod, Ihor; Todo, Y.; ...

2017-06-23

Energetic particles are inherent to toroidal fusion systems and can drive instabilities in the Alfvén frequency range, leading to decreased heating efficiency, high heat fluxes on plasma-facing components, and decreased ignition margin. The applicability of global gyrokinetic simulation methods to macroscopic instabilities has now been demonstrated and it is natural to extend these methods to 3D configurations such as stellarators, tokamaks with 3D coils and reversed field pinch helical states. This has been achieved by coupling the GTC global gyrokinetic PIC model to the VMEC equilibrium model, including 3D effects in the field solvers and particle push. Here, this papermore » demonstrates the application of this new capability to the linearized analysis of Alfvénic instabilities in the LHD stellarator. For normal shear iota profiles, toroidal Alfvén instabilities in the n = 1 and 2 toroidal mode families are unstable with frequencies in the 75 to 110 kHz range. Also, an LHD case with non-monotonic shear is considered, indicating reductions in growth rate for the same energetic particle drive. Finally, since 3D magnetic fields will be present to some extent in all fusion devices, the extension of gyrokinetic models to 3D configurations is an important step for the simulation of future fusion systems.« less

Associations between long chain polyunsaturated fatty acids and cardiovascular lipid risk factors in youth with type 1 diabetes: SEARCH Nutrition Ancillary Study

PubMed Central

Couch, Sarah C.; Crandell, Jamie; King, Irena; Peairs, Abigail; Shah, Amy S; Dolan, Lawrence M; Tooze, Janet; Crume, Tessa; Mayer-Davis, Elizabeth

2017-01-01

Purpose In this longitudinal study we explored the relationships between plasma n-3 and n-6 polyunsaturated fatty acids (PUFAs) and Δ5 and Δ6 desaturase activities (D5D and D6D, respectively) and fasting lipids in youth with type 1 diabetes (T1D). Methods Incident cases of T1D in youth <20 years of age who were seen for a baseline study visit (N=914) and a 1-year follow-up visit (N=416) were included. Fasting blood samples were obtained at each visit and plasma phospholipid n-6 PUFAs were measured, which included linoleic acid (LA), dihomo-γ-linolenic acid (DGLA) and arachidonic acid (AA); n-3 PUFAs included α-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Estimated D5D and D6D were calculated as FA product-to-precursor ratios, where D5D= AA/DGLA and D6D = DGLA/LA. To examine the longitudinal relationships between long chain PUFAs, desaturase activities and fasting plasma lipids in youth with T1D mixed effects models were used for each individual PUFAs, D5D and D6D, adjusted for demographics, clinic site, diabetes duration, insulin regimen, insulin dose/kg, HbA1c, insulin sensitivity score, and body mass index with random effects to account for the repeated measurements. Findings Favorable lipid associations were found between LA and low-density lipoprotein (LDL) cholesterol (β= −0.58, P<0.05); AA, plasma triglycerides (TG) (β= −0.04, P<0.05) and TG/ high-density lipoprotein (HDL)-C ratio (β= −0.04, P<0.05); and D5D, plasma TG (β= −0.2, P<0.05) and TG/HDL-cholesterol ratio (β= −0.23, P<0.05). Findings were mixed for the n-3 PUFAs and DGLA: ALA was positively associated with plasma TG (β= 0.33, P<0.05) and HDL cholesterol (β= 9.86, P<0.05); EPA was positively associated with total cholesterol (β= 8.17, P<0.05), LDL cholesterol (β=5.74, P<0.01) and HDL cholesterol (β= 2.27, P<0.01); and DGLA was positively associated with TG/HDL-cholesterol ratio (β= 0.05, P<0.05) Conclusion Findings suggest that the most abundant PUFA, LA as well as its metabolic bi-product AA, may be important targets for CVD lipid risk factor reduction in youth with T1D. PMID:27836680

Protective effects of sea buckthorn polysaccharide extracts against LPS/d-GalN-induced acute liver failure in mice via suppressing TLR4-NF-κB signaling.

PubMed

Liu, Huan; Zhang, Wei; Dong, Shichao; Song, Liang; Zhao, Shimin; Wu, Chunyan; Wang, Xue; Liu, Fang; Xie, Jiming; Wang, Jinling; Wang, Yuzhen

2015-12-24

Sea buckthorn (Hippophae rhamnoides L.) berries have been traditionally used to treat gastric disorders, cardiovascular problems, and liver injuries in oriental medicinal system. This study aimed to explore the protective effects and mechanisms of the polysaccharide extracts of Sea buckthorn (HRP) berries against lipopolysaccharide (LPS) and d-galactosamine hydrochloride (d-GalN)-induced acute liver failure in mice. HRP was isolated by hot-water extraction and characterized by HPLC and infrared spectrum analysis. The total carbohydrate, uronic acid and protein contents of HRP were measured by a spectrophotometric method. Mice were orally administrated with HRP (50, 100, 200mg/kg) once daily for 14 consecutive days prior to the challenge with LPS (50 μg/kg) and d-GalN (300 mg/kg). Animals of positive control group were intraperitoneally injected with dexamethasone (10mg/kg). Mice were sacrificed at 8h after LPS/d-GalN injection. Pretreatment with HRP significantly inhibited LPS/d-GalN-induced increases in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, which were accompanied by alleviated liver injuries and reduced production of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). HRP was also found to reduce malondialdehyde (MDA) content and to restore superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities. Furthermore, HRP supplementation dose-dependently inhibited the expression of Toll-like receptor 4 (TLR4), phosphorylated extracellular signal-regulated kinase (p-ERK), phosphorylated c-Jun N-terminal kinase (p-JNK), and phosphorylated mitogen activated protein kinase 38 (p-p38 MAPK) in the liver of LPS/d-GalN challenged mice. Pretreatment with HRP also inhibited LPS/d-GalN-induced activation and translocation of nuclear factor-κB (NF-κB). This study indicates that pretreatment with HRP protects against LPS/d-GalN-induced liver injury in mice via suppressing the TLR4-NF-κB signaling pathway. Sea buckthorn may be a hopeful drug for prevention of acute live injury. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The First Intervention Study in Elder Self-Neglect: A Randomized Clinical Trial to Improve Vitamin D Levels

NASA Technical Reports Server (NTRS)

Burnett, Jason; Hochschild, Ann; Smith, Scott M.; Diamond, Pam; Stotts, Angela; Dyer, Carmel

2011-01-01

Despite high mortality rates, elder self-neglect is characterized by refusal of medical and social interventions. To date there have been no tested clinical interventions in elders who self-neglect. Previous research from the TEAM Institute has shown significantly low vitamin D levels in this population. This study aimed to determine the feasibility of a clinical intervention. Replacement of vitamin D was chosen because of its ease of administration and favorable safety profile. Methods: A randomized clinical trial using directly observed therapy of vitamin D was conducted using 50 elders, >65 years of age, with Adult Protective Services (APS) validated self-neglect. A staggered intervention with waiting controls was used to maximize statistical power. One-third (n=17) of the group was administered 50,000 IU vitamin D2 (ergocalciferol) monthly and the remainder (n=33) were administered 400 IU monthly. Serum 25-OH vitamin D was assessed at baseline and 5-months. Results: 69% agreed to participate in the study and of those n=40 (80%) remained at 5-months. At baseline, 12% (n=7) were deficient in vitamin D (<30nmol/L) and approximately 38% (n=22) had inadequate vitamin D levels (<50nmol/L). The baseline 25-OH vitamin D level was 59 nmol/L +25 (mean SD), and increased significantly to 72nmol/L +21 nmol/L at 5-months. Conclusion: These data are the first to provide evidence that clinical interventions are feasible in elders who self-neglect. The increase in vitamin D levels confirmed that the study personnel were able to successfully intervene community-dwelling elders with self-neglect. This study sets the precedent for future intervention and prevention studies

Childhood Lead Exposure in the Palestinian Authority, Israel, and Jordan: Results from the Middle Eastern Regional Cooperation Project, 1996–2000

PubMed Central

Safi, Jamal; Fischbein, Alf; Haj, Sameer El; Sansour, Ramzi; Jaghabir, Madi; Hashish, Mohammed Abu; Suleiman, Hassan; Safi, Nimer; Abu-Hamda, Abed; Witt, Joyce K.; Platkov, Efim; Reingold, Steven; Alayyan, Amber; Berman, Tamar; Bercovitch, Matti; Choudhri, Yogesh; Richter, Elihu D.

2006-01-01

In the Middle East, the major sources of lead exposure have been leaded gasoline, lead-contaminated flour from traditional stone mills, focal exposures from small battery plants and smelters, and kohl (blue color) in cosmetics. In 1998–2000, we measured blood lead (PbB) levels in children 2–6 years of age in Israel, Jordan, and the Palestinian Authority (n = 1478), using a fingerstick method. Mean (peak; percentage > 10 μg/dL) PbB levels in Israel (n = 317), the West Bank (n = 344), Jordan (n = 382), and Gaza (n = 435) were 3.2 μg/dL (18.2; 2.2%), 4.2 μg/dL (25.7; 5.2%), 3.2 μg/dL (39.3; < 1%), and 8.6 μg/dL (> 80.0; 17.2%), respectively. High levels in Gaza were all among children living near a battery factory. The findings, taken together with data on time trends in lead emissions and in PbB in children in previous years, indicate the benefits from phasing out of leaded gasoline but state the case for further reductions and investigation of hot spots. The project demonstrated the benefits of regional cooperation in planning and carrying out a jointly designed project. PMID:16759995

Quantum Algorithms to Simulate Many-Body Physics of Correlated Fermions

NASA Astrophysics Data System (ADS)

Jiang, Zhang; Sung, Kevin J.; Kechedzhi, Kostyantyn; Smelyanskiy, Vadim N.; Boixo, Sergio

2018-04-01

Simulating strongly correlated fermionic systems is notoriously hard on classical computers. An alternative approach, as proposed by Feynman, is to use a quantum computer. We discuss simulating strongly correlated fermionic systems using near-term quantum devices. We focus specifically on two-dimensional (2D) or linear geometry with nearest-neighbor qubit-qubit couplings, typical for superconducting transmon qubit arrays. We improve an existing algorithm to prepare an arbitrary Slater determinant by exploiting a unitary symmetry. We also present a quantum algorithm to prepare an arbitrary fermionic Gaussian state with O (N2) gates and O (N ) circuit depth. Both algorithms are optimal in the sense that the numbers of parameters in the quantum circuits are equal to those describing the quantum states. Furthermore, we propose an algorithm to implement the 2D fermionic Fourier transformation on a 2D qubit array with only O (N1.5) gates and O (√{N }) circuit depth, which is the minimum depth required for quantum information to travel across the qubit array. We also present methods to simulate each time step in the evolution of the 2D Fermi-Hubbard model—again on a 2D qubit array—with O (N ) gates and O (√{N }) circuit depth. Finally, we discuss how these algorithms can be used to determine the ground-state properties and phase diagrams of strongly correlated quantum systems using the Hubbard model as an example.

Mathematical analysis of the Photovoltage Decay (PVD) method for minority carrier lifetime measurements

NASA Technical Reports Server (NTRS)

Vonroos, O. H.

1982-01-01

When the diffusion length of minority carriers becomes comparable with or larger than the thickness of a p-n junction solar cell, the characteristic decay of the photon-generated voltage results from a mixture of contributions with different time constants. The minority carrier recombination lifetime tau and the time constant l(2)/D, where l is essentially the thickness of the cell and D the minority carrier diffusion length, determine the signal as a function of time. It is shown that for ordinary solar cells (n(+)-p junctions), particularly when the diffusion length L of the minority carriers is larger than the cell thickness l, the excess carrier density decays according to exp (-t/tau-pi(2)Dt/4l(2)), tau being the lifetime. Therefore, tau can be readily determined by the photovoltage decay method once D and L are known.

Tensor scale: An analytic approach with efficient computation and applications☆

PubMed Central

Xu, Ziyue; Saha, Punam K.; Dasgupta, Soura

2015-01-01

Scale is a widely used notion in computer vision and image understanding that evolved in the form of scale-space theory where the key idea is to represent and analyze an image at various resolutions. Recently, we introduced a notion of local morphometric scale referred to as “tensor scale” using an ellipsoidal model that yields a unified representation of structure size, orientation and anisotropy. In the previous work, tensor scale was described using a 2-D algorithmic approach and a precise analytic definition was missing. Also, the application of tensor scale in 3-D using the previous framework is not practical due to high computational complexity. In this paper, an analytic definition of tensor scale is formulated for n-dimensional (n-D) images that captures local structure size, orientation and anisotropy. Also, an efficient computational solution in 2- and 3-D using several novel differential geometric approaches is presented and the accuracy of results is experimentally examined. Also, a matrix representation of tensor scale is derived facilitating several operations including tensor field smoothing to capture larger contextual knowledge. Finally, the applications of tensor scale in image filtering and n-linear interpolation are presented and the performance of their results is examined in comparison with respective state-of-art methods. Specifically, the performance of tensor scale based image filtering is compared with gradient and Weickert’s structure tensor based diffusive filtering algorithms. Also, the performance of tensor scale based n-linear interpolation is evaluated in comparison with standard n-linear and windowed-sinc interpolation methods. PMID:26236148

Characterizing 3D grain size distributions from 2D sections in mylonites using a modified version of the Saltykov method

NASA Astrophysics Data System (ADS)

Lopez-Sanchez, Marco; Llana-Fúnez, Sergio

2016-04-01

The understanding of creep behaviour in rocks requires knowledge of 3D grain size distributions (GSD) that result from dynamic recrystallization processes during deformation. The methods to estimate directly the 3D grain size distribution -serial sectioning, synchrotron or X-ray-based tomography- are expensive, time-consuming and, in most cases and at best, challenging. This means that in practice grain size distributions are mostly derived from 2D sections. Although there are a number of methods in the literature to derive the actual 3D grain size distributions from 2D sections, the most popular in highly deformed rocks is the so-called Saltykov method. It has though two major drawbacks: the method assumes no interaction between grains, which is not true in the case of recrystallised mylonites; and uses histograms to describe distributions, which limits the quantification of the GSD. The first aim of this contribution is to test whether the interaction between grains in mylonites, i.e. random grain packing, affects significantly the GSDs estimated by the Saltykov method. We test this using the random resampling technique in a large data set (n = 12298). The full data set is built from several parallel thin sections that cut a completely dynamically recrystallized quartz aggregate in a rock sample from a Variscan shear zone in NW Spain. The results proved that the Saltykov method is reliable as long as the number of grains is large (n > 1000). Assuming that a lognormal distribution is an optimal approximation for the GSD in a completely dynamically recrystallized rock, we introduce an additional step to the Saltykov method, which allows estimating a continuous probability distribution function of the 3D grain size population. The additional step takes the midpoints of the classes obtained by the Saltykov method and fits a lognormal distribution with a trust region using a non-linear least squares algorithm. The new protocol is named the two-step method. The conclusion of this work is that both the Saltykov and the two-step methods are accurate and simple enough to be useful in practice in rocks, alloys or ceramics with near-equant grains and expected lognormal distributions. The Saltykov method is particularly suitable to estimate the volumes of particular grain fractions, while the two-step method to quantify the full GSD (mean and standard deviation in log grain size). The two-step method is implemented in a free, open-source and easy-to-handle script (see http://marcoalopez.github.io/GrainSizeTools/).

Efficient generation of 3D hologram for American Sign Language using look-up table

NASA Astrophysics Data System (ADS)

Park, Joo-Sup; Kim, Seung-Cheol; Kim, Eun-Soo

2010-02-01

American Sign Language (ASL) is one of the languages giving the greatest help for communication of the hearing impaired person. Current 2-D broadcasting, 2-D movies are used the ASL to give some information, help understand the situation of the scene and translate the foreign language. These ASL will not be disappeared in future three-dimensional (3-D) broadcasting or 3-D movies because the usefulness of the ASL. On the other hands, some approaches for generation of CGH patterns have been suggested like the ray-tracing method and look-up table (LUT) method. However, these methods have some drawbacks that needs much time or needs huge memory size for look-up table. Recently, a novel LUT (N-LUT) method for fast generation of CGH patterns of 3-D objects with a dramatically reduced LUT without the loss of computational speed was proposed. Therefore, we proposed the method to efficiently generate the holographic ASL in holographic 3DTV or 3-D movies using look-up table method. The proposed method is largely consisted of five steps: construction of the LUT for each ASL images, extraction of characters in scripts or situation, call the fringe patterns for characters in the LUT for each ASL, composition of hologram pattern for 3-D video and hologram pattern for ASL and reconstruct the holographic 3D video with ASL. Some simulation results confirmed the feasibility of the proposed method in efficient generation of CGH patterns for ASL.

Dosimetry and prescription in liver radioembolization with 90Y microspheres: 3D calculation of tumor-to-liver ratio from global 99mTc-MAA SPECT information

NASA Astrophysics Data System (ADS)

Mañeru, Fernando; Abós, Dolores; Bragado, Laura; Fuentemilla, Naiara; Caudepón, Fernando; Pellejero, Santiago; Miquelez, Santiago; Rubio, Anastasio; Goñi, Elena; Hernández-Vitoria, Araceli

2017-12-01

Dosimetry in liver radioembolization with 90Y microspheres is a fundamental tool, both for the optimization of each treatment and for improving knowledge of the treatment effects in the tissues. Different options are available for estimating the administered activity and the tumor/organ dose, among them the so-called partition method. The key factor in the partition method is the tumor/normal tissue activity uptake ratio (T/N), which is obtained by a single-photon emission computed tomography (SPECT) scan during a pre-treatment simulation. The less clear the distinction between healthy and tumor parenchyma within the liver, the more difficult it becomes to estimate the T/N ratio; therefore the use of the method is limited. This study presents a methodology to calculate the T/N ratio using global information from the SPECT. The T/N ratio is estimated by establishing uptake thresholds consistent with previously performed volumetry. This dose calculation method was validated against 3D voxel dosimetry, and was also compared with the standard partition method based on freehand regions of interest (ROI) outlining on SPECT slices. Both comparisons were done on a sample of 20 actual cases of hepatocellular carcinoma treated with resin microspheres. The proposed method and the voxel dosimetry method yield similar results, while the ROI-based method tends to over-estimate the dose to normal tissues. In addition, the variability associated with the ROI-based method is more extreme than the other methods. The proposed method is simpler than either the ROI or voxel dosimetry approaches and avoids the subjectivity associated with the manual selection of regions.

Isotopic Methods for Determining the Relative Importance of Bioavailability Versus Trophic Position in Controlling Mercury Concentrations in Everglades Mosquitofish

NASA Astrophysics Data System (ADS)

Bemis, B. E.; Kendall, C.

2007-12-01

The concentration of mercury in fish tissues is widely used as an indicator of the magnitude of mercury contamination in aquatic ecosystems. Eastern mosquitofish (Gambusia holbrookii) is an important sentinel species used for this purpose in the varied environments of the Florida Everglades, because mosquitofish are abundant, have a short lifespan, and migrate little. Like other freshwater fish, the primary route of mercury uptake into mosquitofish tissues is through diet as bioavailable methylmercury. Yet, it is unclear whether variations in mosquitofish mercury observed across the Everglades are due primarily to differences in bioaccumulation (i.e., trophic position) or abundance of methylmercury available to the food web base. We use isotopic methods to investigate the importance of these two controls on mosquitofish mercury at the landscape scale. As part of the USEPA REMAP project, mosquitofish and periphyton were collected during September 1996 from over one hundred sites throughout the Everglades and analyzed for mercury concentration. The USGS analyzed splits of the samples for nitrogen (d15N), carbon (d13C), and sulfur (d34S) isotopic composition, to investigate the causes of mercury variations. The d15N value of tissues is often used to estimate the relative trophic positions of organisms in a food web, and should correlate positively with tissue mercury if bioaccumulation is an important control on mosquitofish mercury concentration. The d13C value can be useful for detecting differences in food web base (e.g., algal versus detrital), and thus the entry point of contaminants. Tissue d34S potentially indicates the extent of dissimilatory sulfate reduction in sediments, a process used by sulfate-reducing bacteria (SRB) during conversion of inorganic Hg(II) to bioavailable methylmercury. Because this process increases the d34S value of remaining sulfate, which enters the food web base, mosquitofish sulfur isotopes should show positive correlations with SRB activity, methylmercury production, and mosquitofish mercury concentrations. The d15N, d13C, and d34S values of mosquitofish and periphyton are significantly correlated, indicating that a component of the bulk periphyton analyzed in this study is part of the mosquitofish food web. Mosquitofish mercury does not correlate significantly with tissue d15N or the d15N difference between mosquitofish and periphyton. Thus, differences in trophic level (and bioaccumulation) among the fish do not contribute a detectable influence on mercury variations in the samples studied. In contrast with the d15N results, mosquitofish mercury levels show significant, positive correlations with mosquitofish d34S and the d34S difference between mosquitofish and periphyton. This suggests that during the period studied, mosquitofish mercury concentrations in the Everglades were primarily influenced by the bioavailability of mercury, rather than by differences in trophic position. This study demonstrates that isotopic measurements, especially d34S, can be useful tools for determining causes of high mercury concentrations in fish populations.

Development of a Regional 3-D Velocity Model of the Pakistan Region for Improved Seismic Event Location

DTIC Science & Technology

2006-04-01

the Engdahl, el al. (1998) database . Our results show that the new model better fits the data COm~ared to both the initial model and the alobal l -D...34SOUICU" m the cal-. Tbe Podvh-Lemmte method sohns the eikonal equation m a 3-D medium using a htd&mme . . spprmimatian. It c a n ~ e l y m o d e l ~ ~ o

The Adenosine Receptor Antagonist, 7-Methylxanthine, Alters Emmetropizing Responses in Infant Macaques

PubMed Central

Hung, Li-Fang; Arumugam, Baskar; Ostrin, Lisa; Patel, Nimesh; Trier, Klaus; Jong, Monica; III, Earl L. Smith

2018-01-01

Purpose Previous studies suggest that the adenosine receptor antagonist, 7-methylxanthine (7-MX), retards myopia progression. Our aim was to determine whether 7-MX alters the compensating refractive changes produced by defocus in rhesus monkeys. Methods Starting at age 3 weeks, monkeys were reared with −3 diopter (D; n = 10; 7-MX −3D/pl) or +3D (n = 6; 7-MX +3D/pl) spectacles over their treated eyes and zero-powered lenses over their fellow eyes. In addition, they were given 100 mg/kg of 7-MX orally twice daily throughout the lens-rearing period (age 147 ± 4 days). Comparison data were obtained from lens-reared controls (−3D/pl, n = 17; +3D/pl, n = 9) and normal monkeys (n = 37) maintained on a standard diet. Refractive status, corneal power, and axial dimensions were assessed biweekly. Results The −3D/pl and +3D/pl lens-reared controls developed compensating myopic (−2.10 ± 1.07 D) and hyperopic anisometropias (+1.86 ± 0.54 D), respectively. While the 7-MX +3D/pl monkeys developed hyperopic anisometropias (+1.79 ± 1.11 D) that were similar to those observed in +3D/pl controls, the 7-MX −3D/pl animals did not consistently exhibit compensating myopia in their treated eyes and were on average isometropic (+0.35 ± 1.96 D). The median refractive errors for both eyes of the 7-MX −3D/pl (+5.47 D and +4.38 D) and 7-MX +3D/pl (+5.28 and +3.84 D) monkeys were significantly more hyperopic than that for normal monkeys (+2.47 D). These 7-MX–induced hyperopic ametropias were associated with shorter vitreous chambers and thicker choroids. Conclusions In primates, 7-MX reduced the axial myopia produced by hyperopic defocus, augmented hyperopic shifts in response to myopic defocus, and induced hyperopia in control eyes. The results suggest that 7-MX has therapeutic potential in efforts to slow myopia progression. PMID:29368006

Effectiveness of school food environment policies on children’s dietary behaviors: A systematic review and meta-analysis

PubMed Central

Bakogianni, Ioanna; Trichia, Eirini; Whitsel, Laurie P.; Story, Mary; Peñalvo, Jose L.; Mozaffarian, Dariush

2018-01-01

Background School food environment policies may be a critical tool to promote healthy diets in children, yet their effectiveness remains unclear. Objective To systematically review and quantify the impact of school food environment policies on dietary habits, adiposity, and metabolic risk in children. Methods We systematically searched online databases for randomized or quasi-experimental interventions assessing effects of school food environment policies on children’s dietary habits, adiposity, or metabolic risk factors. Data were extracted independently and in duplicate, and pooled using inverse-variance random-effects meta-analysis. Habitual (within+outside school) dietary intakes were the primary outcome. Heterogeneity was explored using meta-regression and subgroup analysis. Funnel plots, Begg’s and Egger’s test evaluated potential publication bias. Results From 6,636 abstracts, 91 interventions (55 in US/Canada, 36 in Europe/New Zealand) were included, on direct provision of healthful foods/beverages (N = 39 studies), competitive food/beverage standards (N = 29), and school meal standards (N = 39) (some interventions assessed multiple policies). Direct provision policies, which largely targeted fruits and vegetables, increased consumption of fruits by 0.27 servings/d (n = 15 estimates (95%CI: 0.17, 0.36)) and combined fruits and vegetables by 0.28 servings/d (n = 16 (0.17, 0.40)); with a slight impact on vegetables (n = 11; 0.04 (0.01, 0.08)), and no effects on total calories (n = 6; -56 kcal/d (-174, 62)). In interventions targeting water, habitual intake was unchanged (n = 3; 0.33 glasses/d (-0.27, 0.93)). Competitive food/beverage standards reduced sugar-sweetened beverage intake by 0.18 servings/d (n = 3 (-0.31, -0.05)); and unhealthy snacks by 0.17 servings/d (n = 2 (-0.22, -0.13)), without effects on total calories (n = 5; -79 kcal/d (-179, 21)). School meal standards (mainly lunch) increased fruit intake (n = 2; 0.76 servings/d (0.37, 1.16)) and reduced total fat (-1.49%energy; n = 6 (-2.42, -0.57)), saturated fat (n = 4; -0.93%energy (-1.15, -0.70)) and sodium (n = 4; -170 mg/d (-242, -98)); but not total calories (n = 8; -38 kcal/d (-137, 62)). In 17 studies evaluating adiposity, significant decreases were generally not identified; few studies assessed metabolic factors (blood lipids/glucose/pressure), with mixed findings. Significant sources of heterogeneity or publication bias were not identified. Conclusions Specific school food environment policies can improve targeted dietary behaviors; effects on adiposity and metabolic risk require further investigation. These findings inform ongoing policy discussions and debates on best practices to improve childhood dietary habits and health. PMID:29596440

Quantitative comparison of two independent lateral force calibration techniques for the atomic force microscope.

PubMed

Barkley, Sarice S; Deng, Zhao; Gates, Richard S; Reitsma, Mark G; Cannara, Rachel J

2012-02-01

Two independent lateral-force calibration methods for the atomic force microscope (AFM)--the hammerhead (HH) technique and the diamagnetic lateral force calibrator (D-LFC)--are systematically compared and found to agree to within 5 % or less, but with precision limited to about 15 %, using four different tee-shaped HH reference probes. The limitations of each method, both of which offer independent yet feasible paths toward traceable accuracy, are discussed and investigated. We find that stiff cantilevers may produce inconsistent D-LFC values through the application of excessively high normal loads. In addition, D-LFC results vary when the method is implemented using different modes of AFM feedback control, constant height and constant force modes, where the latter is more consistent with the HH method and closer to typical experimental conditions. Specifically, for the D-LFC apparatus used here, calibration in constant height mode introduced errors up to 14 %. In constant force mode using a relatively stiff cantilever, we observed an ≈ 4 % systematic error per μN of applied load for loads ≤ 1 μN. The issue of excessive load typically emerges for cantilevers whose flexural spring constant is large compared with the normal spring constant of the D-LFC setup (such that relatively small cantilever flexural displacements produce relatively large loads). Overall, the HH method carries a larger uncertainty, which is dominated by uncertainty in measurement of the flexural spring constant of the HH cantilever as well as in the effective length dimension of the cantilever probe. The D-LFC method relies on fewer parameters and thus has fewer uncertainties associated with it. We thus show that it is the preferred method of the two, as long as care is taken to perform the calibration in constant force mode with low applied loads.

Systems Biology and Ratio-Based, Real-Time Disease Surveillance.

PubMed

Fair, J M; Rivas, A L

2015-08-01

Most infectious disease surveillance methods are not well fit for early detection. To address such limitation, here we evaluated a ratio- and Systems Biology-based method that does not require prior knowledge on the identity of an infective agent. Using a reference group of birds experimentally infected with West Nile virus (WNV) and a problem group of unknown health status (except that they were WNV-negative and displayed inflammation), both groups were followed over 22 days and tested with a system that analyses blood leucocyte ratios. To test the ability of the method to discriminate small data sets, both the reference group (n = 5) and the problem group (n = 4) were small. The questions of interest were as follows: (i) whether individuals presenting inflammation (disease-positive or D+) can be distinguished from non-inflamed (disease-negative or D-) birds, (ii) whether two or more D+ stages can be detected and (iii) whether sample size influences detection. Within the problem group, the ratio-based method distinguished the following: (i) three (one D- and two D+) data classes; (ii) two (early and late) inflammatory stages; (iii) fast versus regular or slow responders; and (iv) individuals that recovered from those that remained inflamed. Because ratios differed in larger magnitudes (up to 48 times larger) than percentages, it is suggested that data patterns are likely to be recognized when disease surveillance methods are designed to measure inflammation and utilize ratios. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

FTIR, FT-RAMAN, NMR, spectra, normal co-ordinate analysis, NBO, NLO and DFT calculation of N,N-diethyl-4-methylpiperazine-1-carboxamide molecule

NASA Astrophysics Data System (ADS)

Muthu, S.; Elamurugu Porchelvi, E.

2013-11-01

The Fourier Transform Infrared (FT-IR) and FT-Raman of N,N-diethyl-4-methylpiperazine-1-carboxamide (NND4MC) have been recorded and analyzed. The structure of the compound was optimized and the structural characteristics were determined by density functional theory (DFT) using B3LYP method with 6-31G(d,p) and 6-311G(d,p) basis sets. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. The theoretically predicted FT-IR and FT-Raman spectra of the title molecule have been constructed. The detailed interpretation of the vibrational spectra has been carried out with aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The results show that electron density (ED) in the σ* and π* antibonding orbitals and second order delocalization energies (E2) confirm the occurrence of intramolecular charge transfer (ICT) within the molecule. The electronic dipole moment (μD) and the first hyperpolarizability (βtot) values of the investigated molecule were computed using Density Functional Theory (DFT/B3LYP) with 6-31G(d,p) and 6-311G(d,p) basis sets. The calculated results also show that the NND4MC molecule may have microscopy nonlinear optical (NLO) behavior with non zero values. Mulliken atomic charges of NND4MC were calculated. The 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results. The UV-Vis spectrum of the compound was recorded. The theoretical electronic absorption spectra have been calculated by using CIS, TD-DFT methods. A study on the electronic properties, such as HOMO and LUMO energies, molecular electrostatic potential (MEP) were also performed.

AuNx stabilization with interstitial nitrogen atoms: A Density Functional Theory Study

NASA Astrophysics Data System (ADS)

Quintero, J. H.; Gonzalez-Hernandez, R.; Ospina, R.; Mariño, A.

2017-06-01

Researchers have been studying 4d and 5d Series Transition Metal Nitrides lately as a result of the experimental production of AuN, PtN, CuN. In this paper, we used the Density Functional Theory (DFT) implementing a pseudopotential plane-wave method to study the incorporation of nitrogen atoms in the face-centered cube (fcc) lattice of gold (Au). First, we took the fcc structure of gold, and gradually located the nitrogen atoms in tetrahedral (TH) and octahedral (OH) interstitial sites. AuN stabilized in: 2OH (30%), 4OH and 4TH (50%), 4OH - 2TH (close to the wurtzite structure) and 6TH (60%). This leads us to think that AuN behaves like a Transition Metal Nitride since the nitrogen atoms look for tetrahedral sites.

Insertion of two-dimensional photonic crystal pattern on p-GaN layer of GaN-based light-emitting diodes using bi-layer nanoimprint lithography.

PubMed

Byeon, Kyeong-Jae; Hwang, Seon-Yong; Hong, Chang-Hee; Baek, Jong Hyeob; Lee, Heon

2008-10-01

Nanoimprint lithography (NIL) was adapted to fabricate two-dimensional (2-D) photonic crystal (PC) pattern on the p-GaN layer of InGaN/GaN multi quantum well light-emitting diodes (LEDs) structure to improve the light extraction efficiency. For the uniform transfer of the PC pattern, a bi-layer imprinting method with liquid phase resin was used. The p-GaN layer was patterned with a periodic array of holes by an inductively coupled plasma etching process, based on SiCl4/Ar plasmas. As a result, 2-D photonic crystal patterns with 144 nm, 200 nm and 347 nm diameter holes were uniformly formed on the p-GaN layer and the photoluminescence (PL) intensity of each patterned LED samples was increased by more than 2.6 times, as compared to that of the un-patterned LED sample.

Exploring the dynamics of reaction N((2)D)+C2H4 with crossed molecular-beam experiments and quantum-chemical calculations.

PubMed

Lee, Shih-Huang; Chin, Chih-Hao; Chen, Wei-Kan; Huang, Wen-Jian; Hsieh, Chu-Chun

2011-05-14

We conducted the title reaction using a crossed molecular-beam apparatus, quantum-chemical calculations, and RRKM calculations. Synchrotron radiation from an undulator served to ionize selectively reaction products by advantage of negligibly small dissociative ionization. We observed two products with gross formula C(2)H(3)N and C(2)H(2)N associated with loss of one and two hydrogen atoms, respectively. Measurements of kinetic-energy distributions, angular distributions, low-resolution photoionization spectra, and branching ratios of the two products were carried out. Furthermore, we evaluated total branching ratios of various exit channels using RRKM calculations based on the potential-energy surface of reaction N((2)D)+C(2)H(4) established with the method CCSD(T)/6-311+G(3df,2p)//B3LYP/6-311G(d,p)+ZPE[B3LYP/6-311G(d,p)]. The combination of experimental and computational results allows us to reveal the reaction dynamics. The N((2)D) atom adds to the C=C π-bond of ethene (C(2)H(4)) to form a cyclic complex c-CH(2)(N)CH(2) that directly ejects a hydrogen atom or rearranges to other intermediates followed by elimination of a hydrogen atom to produce C(2)H(3)N; c-CH(2)(N)CH+H is the dominant product channel. Subsequently, most C(2)H(3)N radicals, notably c-CH(2)(N)CH, further decompose to CH(2)CN+H. This work provides results and explanations different from the previous work of Balucani et al. [J. Phys. Chem. A, 2000, 104, 5655], indicating that selective photoionization with synchrotron radiation as an ionization source is a good choice in chemical dynamics research.

Dosimetric comparison of helical tomotherapy, intensity-modulated radiation therapy, volumetric-modulated arc therapy, and 3-dimensional conformal therapy for the treatment of T1N0 glottic cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ekici, Kemal, E-mail: drkemal06@hotmail.com; Pepele, Eda K.; Yaprak, Bahaddin

2016-01-01

Various radiotherapy planning methods for T1N0 laryngeal cancer have been proposed to decrease normal tissue toxicity. We compare helical tomotherapy (HT), linac-based intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT), and 3-D conformal radiotherapy (3D-CRT) techniques for T1N0 laryngeal cancer. Overall, 10 patients with T1N0 laryngeal cancer were selected and evaluated. Furthermore, 10 radiotherapy treatment plans have been created for all 10 patients, including HT, IMRT, VMAT, and 3D-CRT. IMRT, VMAT, and HT plans vs 3D-CRT plans consistently provided superior planning target volume (PTV) coverage. Similar target coverage was observed between the 3 IMRT modalities. Compared with 3D-CRT, IMRT, HT,more » and VMAT significantly reduced the mean dose to the carotid arteries. VMAT resulted in the lowest mean dose to the submandibular and thyroid glands. Compared with 3D-CRT, IMRT, HT, and VMAT significantly increased the maximum dose to the spinal cord It was observed that the 3 IMRT modalities studied showed superior target coverage with less variation between each plan in comparison with 3D-CRT. The 3D-CRT plans performed better at the D{sub max} of the spinal cord. Clinical investigation is warranted to determine if these treatment approaches would translate into a reduction in radiation therapy–induced toxicities.« less

The Effects of Exercise Therapy on CVD Risk Factors in Women

PubMed Central

Hur, Sun; Kim, Seon-Rye

2014-01-01

[Purpose] The purpose of this study was to search for the association of Type D personality and CVD risk factors through comparison of the association of exercise participation with CVD risk factors in women. [Subjects] The research subjects were randomly assigned to four groups: Type D+Exercise (n=12), Type D+non-exercise (n=12), non-Type D+Exercise (n=12), and non-Type D+non-exercise (n=10). The study consisted of 46 participants. [Methods] An aerobic exercise program and meditation were conducted in parallel for 10 months. Stretching was performed for 10 min as a warm-up, and then walking and running on a treadmill at 60 to 70% of HRmax were performed for 40 min three times a week. Blood samples were processed according to standard laboratory procedures. The concentrations of TG and HDL cholesterol were determined enzymatically using a clinical chemistry analyzer (Hitachi High-Technologies Corporation, Tokyo, Japan). [Results] The weight, percentage of body fat, waist circumference, triglyceride concentration, HDL cholesterol concentration, systolic blood pressure, and diastolic blood pressure showed a significant difference between measurement times in the exercise groups. [Conclusion] In conclusion, there were significant differences between groups in terms of cardiovascular disease risk factors. PMID:25276017

Sensory Sensitivities and Discriminations and their Roles in Aviation

DTIC Science & Technology

1991-10-31

asymmetry. Neurology, in press. 5. Zihl JD, Von Cramon D & Mai N (1983) Selective disturbance of movement vision after bilateral brain damage. Brain...1970) Electrophysiological correlate of binocular depth perception in man. Nature 255, 92-4. 1971 16. Regan D & Sperling HG (1971) A method of evoking

The K 2S 2O 8-KOH photoetching system for GaN

NASA Astrophysics Data System (ADS)

Weyher, J. L.; Tichelaar, F. D.; van Dorp, D. H.; Kelly, J. J.; Khachapuridze, A.

2010-09-01

A recently developed photoetching system for n-type GaN, a KOH solution containing the strong oxidizing agent potassium peroxydisulphate (K 2S 2O 8), was studied in detail. By careful selection of the etching parameters, such as the ratio of components and the hydrodynamics, two distinct modes were defined: defect-selective etching (denoted by KSO-D) and polishing (KSO-P). Both photoetching methods can be used under open-circuit (electroless) conditions. Well-defined dislocation-related etch whiskers are formed during KSO-D etching. All types of dislocations are revealed, and this was confirmed by cross-sectional TEM examination of the etched samples. Extended electrically active defects are also clearly revealed. The known relationship between etch rate and carrier concentration for photoetching of GaN in KOH solutions was confirmed for KSO-D etch using Raman measurements. It is shown that during KSO-P etching diffusion is the rate-limiting step, i.e. this etch is suitable for polishing of GaN. Some constraints of the KSO etching system for GaN are discussed and peculiar etch features, so far not understood, are described.

Hybrid Macro-Porous Titanium Ornamented by Degradable 3D Gel/nHA Micro-Scaffolds for Bone Tissue Regeneration

PubMed Central

Yin, Bo; Ma, Pei; Chen, Jun; Wang, Hai; Wu, Gui; Li, Bo; Li, Qiang; Huang, Zhifeng; Qiu, Guixing; Wu, Zhihong

2016-01-01

Porous titanium is a kind of promising material for bone substitution, while its bio-inert property results in demand of modifications to improve the osteointegration capacity. In this study, gelatin (Gel) and nano-hydroxyapatite (nHA) were used to construct 3D micro-scaffolds in the pores of porous titanium in the ratios of Gel:nHA = 1:0, Gel:nHA = 1:1, and Gel:nHA = 1:3, respectively. Cell attachment and proliferation, and gene and protein expression levels of osteogenic markers were evaluated in MC3T3-E1 cells, followed by bone regeneration assessment in a rabbit radius defect model. All hybrid scaffolds with different composition ratio were found to have significant promotional effects in cell adhesion, proliferation and differentiation, in which the group with Gel:nHA = 1:1 showed the best performance in vitro, as well as the most bone regeneration volume in vivo. This 3D micro-scaffolds modification may be an innovative method for porous titanium ornamentation and shows potential application values in clinic. PMID:27092492

Hybrid Macro-Porous Titanium Ornamented by Degradable 3D Gel/nHA Micro-Scaffolds for Bone Tissue Regeneration.

PubMed

Yin, Bo; Ma, Pei; Chen, Jun; Wang, Hai; Wu, Gui; Li, Bo; Li, Qiang; Huang, Zhifeng; Qiu, Guixing; Wu, Zhihong

2016-04-15

Porous titanium is a kind of promising material for bone substitution, while its bio-inert property results in demand of modifications to improve the osteointegration capacity. In this study, gelatin (Gel) and nano-hydroxyapatite (nHA) were used to construct 3D micro-scaffolds in the pores of porous titanium in the ratios of Gel:nHA = 1:0, Gel:nHA = 1:1, and Gel:nHA = 1:3, respectively. Cell attachment and proliferation, and gene and protein expression levels of osteogenic markers were evaluated in MC3T3-E1 cells, followed by bone regeneration assessment in a rabbit radius defect model. All hybrid scaffolds with different composition ratio were found to have significant promotional effects in cell adhesion, proliferation and differentiation, in which the group with Gel:nHA = 1:1 showed the best performance in vitro, as well as the most bone regeneration volume in vivo. This 3D micro-scaffolds modification may be an innovative method for porous titanium ornamentation and shows potential application values in clinic.

Measurement of Activation Cross Sections Producing Short-Lived Nuclei with Pulsed Neutron Beam

NASA Astrophysics Data System (ADS)

Shimizu, Toshiaki; Arakita, Kazumasa; Miyazaki, Itaru; Shibata, Michihiro; Kawade, Kiyoshi; Hori, Jun-ichi; Ochiai, Kentaro; Nishitani, Takeo

2005-05-01

Activation cross sections for the (n, n') reaction were measured by means of the activation method at the neutron energies of 3.1 and 2.54 MeV by using a pulsed neutron beam. Target nuclei were 79Br, 90Zr, 197Au, and 207Pb, whose half-lives were between 0.8 and 8 s. The cross section for the 90Zr (n, n') 90mZr reaction was obtained for the first time in this energy range. The d-D neutrons were generated by bombarding a deuterated titanium target with a 350-keV d+ beam at the 80-degree beam line of the Fusion Neutronics Source at the Japan Atomic Energy Research Institute. In order to obtain reliable activation cross sections, careful attention was paid to correct the efficiency for a volume source, and the self-absorption of gamma rays in an irradiated sample. The systematics of the (n, n') reaction at the neutron energy of 3.1 MeV, which could be predicted within an accuracy of 50%, was proposed on the basis of our data.

Chirality detection of amino acid enantiomers by organic electrochemical transistor.

PubMed

Zhang, Lijun; Wang, Guiheng; Xiong, Can; Zheng, Lei; He, Jianbo; Ding, Yunsheng; Lu, Hongbo; Zhang, Guobing; Cho, Kilwon; Qiu, Longzhen

2018-05-15

Chiral recognition of α-amino acids is attracting increasing interest due to the importance of α-amino acids in protein metabolism as well as in food products and pharmaceuticals. Organic electrochemical transistors (OECTs) with gate electrodes modified with molecularly imprinted polymer (MIP) films were fabricated and successfully used as highly selective and sensitive chiral recognition biosensors for d/l-tryptophan (d/l-Trp) and d/l-tyrosine (d/l-Tyr). The MIP films, which can specifically recognize and has an electrocatalytic effect on the oxidation of Trp and Tyr, together with the amplification function of an OECT, provide a highly sensitive and selective OECT biosensor. The sensor showed a linear response range for l-Trp and L-Tyr from 300 nM to 10 μM with a sensitivity of 3.19 and 3.64 μA/μM, respectivity. And the detection limit for L-Trp and L-Tyr is of 2 nM and 30 nM (S/N > 3). The selectivity factors of L-Trp, D-Trp, L-Tyr and D-Tyr to their enantiomers are 11.6, 3.5, 14.5 and 2.6, respectively. This method can pave the way for widespread applications of OECT-based sensors in chiral material identification. Copyright © 2018 Elsevier B.V. All rights reserved.

Immobilization of sugars in supermacroporous cryogels for the purification of lectins by affinity chromatography.

PubMed

Gonçalves, Gabriel Ramos Ferreira; Gandolfi, Olga Reinert Ramos; Santos, Leandro Soares; Bonomo, Renata Cristina Ferreira; Veloso, Cristiane Martins; Veríssimo, Lizzy Ayra Alcântara; Fontan, Rafael da Costa Ilhéu

2017-11-15

Lectins are glycoproteins that bind to carbohydrates or glycoconjugates by specific interactions. The specificity of lectins to various carbohydrates is a determinant factor in the choice of ligand for the chromatographic matrix when using chromatography as a lectin purification technique. In this work, the immobilization of three different aminated carbohydrates on the surface of macroporous polymeric cryogels was evaluated. Carbohydrates were immobilized on cryogel surfaces via the glutaraldehyde method to create spacer arms, reducing steric hindrance. The immobilized N-acetyl-d-glucosamine and N-acetyl-d-mannosamine concentrations contained approximately 130mg of carbohydrate/g dehydrated cryogel, while the N-acetyl-d-galactosamine contained 105mg of carbohydrate/g dehydrated cryogel. Scanning electron microscopy showed that the physical structure and porosity of the chromatographic columns were not affected by the immobilization process, maintaining an elevated hydration capacity and the macroporous structure of the cryogels. Adsorption of concanavalin A on cryogels functionalized with N-acetyl-d-glucosamine (cryo-d-GlcNAc) was tested, as well as its reuse capability. After 5 cycles of use, cryo-d-GlcNAc was shown to be stable, with an adsorptive capacity of around 50mg/g. Carbohydrate immobilization in polyacrylamide cryogels was satisfactory, with promise for applications in lectin purification processes. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of eight nitrosamines in water at the ng L(-1) levels by liquid chromatography coupled to atmospheric pressure chemical ionization tandem mass spectrometry.

PubMed

Ripollés, Cristina; Pitarch, Elena; Sancho, Juan V; López, Francisco J; Hernández, Félix

2011-09-19

In this work, we have developed a sensitive method for detection and quantification of eight N-nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMor), N-nitrosomethylethylamine (NMEA), N-nitrosopirrolidine (NPyr), N-nitrosodiethylamine (NDEA), N-nitrosopiperidine (NPip), N-nitroso-n-dipropylamine (NDPA) and N-nitrosodi-n-butylamine (NDBA) in drinking water. The method is based on liquid chromatography coupled to tandem mass spectrometry, using atmospheric pressure chemical ionization (APCI) in positive mode with a triple quadrupole analyzer (QqQ). The simultaneous acquisition of two MS/MS transitions in selected reaction monitoring mode (SRM) for each compound, together with the evaluation of their relative intensity, allowed the simultaneous quantification and reliable identification in water at ppt levels. Empirical formula of the product ions selected was confirmed by UHPLC-(Q)TOF MS accurate mass measurements from reference standards. Prior to LC-MS/MS QqQ analysis, a preconcentration step by off-line SPE using coconut charcoal EPA 521 cartridges (by passing 500 mL of water sample) was necessary to improve the sensitivity and to meet regulation requirements. For accurate quantification, two isotope labelled nitrosamines (NDMA-d(6) and NDPA-d(14)) were added as surrogate internal standards to the samples. The optimized method was validated at two concentration levels (10 and 100 ng L(-1)) in drinking water samples, obtaining satisfactory recoveries (between 90 and 120%) and precision (RSD<20%). Limits of detection were found to be in the range of 1-8 ng L(-1). The described methodology has been applied to different types of water samples: chlorinated from drinking water and wastewater treatment plants (DWTP and WWTP, respectively), wastewaters subjected to ozonation and tap waters. Copyright © 2011 Elsevier B.V. All rights reserved.

Genetic characterization of 11 microsatellite loci in Egyptian pigeons (Columba livia domestica) and their cross-species amplification in other Columbidae populations

PubMed Central

Ramadan, Sherif; Dawod, Ahmed; El-Garhy, Osama; Nowier, Amira M.; Eltanany, Marwa; Inoue-Murayama, Miho

2018-01-01

Aim This study aimed to analyze the genetic diversity and relationships of 10 Egyptian pigeon populations belonging to Columba livia domestica speciesusing 11 microsatellite markers and to investigate the success of these markers amplification across another eight pigeon species. Methods Genomic DNA was isolated from feather samples of179 pigeon samples from 10 Egyptian breeds: Asfer Weraq (n=14), Austoraly (n=20), Reehani (n=21), Messawed (n=17), Nemssawy (n=27), Otatti (n=12), Morasla (n=17), Tumbler (n=22), Halaby Asfer (n=10), and Karakandy (n=19) in addition to Japanese feral pigeons (n=30). Genotyping was done using 11 specific polymorphic microsatellite makers. Moreover, 37 samples not belonging to C. livia domestica but belonging to another eight pigeon species were genotyped. The polymerase chain reaction (PCR) products were electrophoresed on an ABI 3130xl DNA Sequencer. The basic measures of genetic diversity and phylogenetic trees were computed using bioinformatics software. Results Across the 10 studied Egyptian populations, the number of alleles per locus ranged from 3 to 19 and the average number of alleles observed was 9.091. The lowest value of expected heterozygosity (0.373) was obtained for the Reehani breed, and the highest value (0.706) was found for Morasla breed. The overall expected heterozygosity of Egyptian pigeons was 0.548. The FST coefficient which indicates fixation coefficients of subpopulations within the total population for the 11 loci varied from 0.318 to 0.114 with a relatively high mean (0.226). In our study, the FIS showed a relatively high average(0.037). The pairwise Reynolds’s genetic distance between the11 studied pigeon populations recorded lower values between Otatti and Austoraly (0.025) and between Morasla and Japanese feral pigeons (0.054). These results are supported by clustering pattern either by the neighbor-joining phylogenetic tree or by a Bayesian clustering of STRUCTURE with the admixture method. Conclusions We confirm the applicability of the CliµD17, CliµT17, CliµD16, CliµD32, CliµT13, CliµD01, PG1, PG2, PG4, PG6, and PG7 microsatellite markers among Egyptian domestic pigeons and across other pigeon species using cross-species amplification method. The information from this study should be useful for genetic characterization and for developing conservation programs of this important species. PMID:29805216

Ohmic contact formation between metal and AlGaN/GaN heterostructure via graphene insertion

NASA Astrophysics Data System (ADS)

Sung Park, Pil; Reddy, Kongara M.; Nath, Digbijoy N.; Yang, Zhichao; Padture, Nitin P.; Rajan, Siddharth

2013-04-01

A simple method for the creation of Ohmic contact to 2D electron gas in AlGaN/GaN high electron-mobility transistors using Cr/graphene layer is demonstrated. A weak temperature dependence of this Ohmic contact observed in the range 77 to 300 K precludes thermionic emission or trap-assisted hopping as possible carrier-transport mechanisms. It is suggested that the Cr/graphene combination acts akin to a doped n-type semiconductor in contact with AlGaN/GaN heterostructure, and promotes carrier transport along percolating Al-lean paths through the AlGaN layer. This use of graphene offers a simple method for making Ohmic contacts to AlGaN/GaN heterostructures, circumventing complex additional processing steps involving high temperatures. These results could have important implications for the fabrication and manufacturing of AlGaN/GaN-based microelectronic and optoelectronic devices/sensors of the future.

Weighted SGD for ℓ p Regression with Randomized Preconditioning.

PubMed

Yang, Jiyan; Chow, Yin-Lam; Ré, Christopher; Mahoney, Michael W

2016-01-01

In recent years, stochastic gradient descent (SGD) methods and randomized linear algebra (RLA) algorithms have been applied to many large-scale problems in machine learning and data analysis. SGD methods are easy to implement and applicable to a wide range of convex optimization problems. In contrast, RLA algorithms provide much stronger performance guarantees but are applicable to a narrower class of problems. We aim to bridge the gap between these two methods in solving constrained overdetermined linear regression problems-e.g., ℓ 2 and ℓ 1 regression problems. We propose a hybrid algorithm named pwSGD that uses RLA techniques for preconditioning and constructing an importance sampling distribution, and then performs an SGD-like iterative process with weighted sampling on the preconditioned system.By rewriting a deterministic ℓ p regression problem as a stochastic optimization problem, we connect pwSGD to several existing ℓ p solvers including RLA methods with algorithmic leveraging (RLA for short).We prove that pwSGD inherits faster convergence rates that only depend on the lower dimension of the linear system, while maintaining low computation complexity. Such SGD convergence rates are superior to other related SGD algorithm such as the weighted randomized Kaczmarz algorithm.Particularly, when solving ℓ 1 regression with size n by d , pwSGD returns an approximate solution with ε relative error in the objective value in (log n ·nnz( A )+poly( d )/ ε 2 ) time. This complexity is uniformly better than that of RLA methods in terms of both ε and d when the problem is unconstrained. In the presence of constraints, pwSGD only has to solve a sequence of much simpler and smaller optimization problem over the same constraints. In general this is more efficient than solving the constrained subproblem required in RLA.For ℓ 2 regression, pwSGD returns an approximate solution with ε relative error in the objective value and the solution vector measured in prediction norm in (log n ·nnz( A )+poly( d ) log(1/ ε )/ ε ) time. We show that for unconstrained ℓ 2 regression, this complexity is comparable to that of RLA and is asymptotically better over several state-of-the-art solvers in the regime where the desired accuracy ε , high dimension n and low dimension d satisfy d ≥ 1/ ε and n ≥ d 2 / ε . We also provide lower bounds on the coreset complexity for more general regression problems, indicating that still new ideas will be needed to extend similar RLA preconditioning ideas to weighted SGD algorithms for more general regression problems. Finally, the effectiveness of such algorithms is illustrated numerically on both synthetic and real datasets, and the results are consistent with our theoretical findings and demonstrate that pwSGD converges to a medium-precision solution, e.g., ε = 10 -3 , more quickly.

Synthesis of 1D Bragg gratings by a layer-aggregation method.

PubMed

Capmany, José; Muriel, Miguel A; Sales, Salvador

2007-08-15

We present what we believe to be a novel method for the synthesis of complex 1D (fiber and waveguide) Bragg gratings, which is based on an impedance reconstruction layer aggregation technique. The main advantage brought by the method is the possibility of synthesizing structures containing defects or discontinuities of the size of the local period, a feature that is not possible with prior reported methods. In addition, this enhanced spatial resolution allows the synthesis of very strong fiber Bragg grating devices providing convergent solutions. The method directly renders the refractive index profile n(z) as it does not rely on the coupled-mode theory.

Unilateral Outer Bow Expanded Cervical Headgear Force System: 3D Analysis Using Finite Element Method

PubMed Central

Mortezai, Omid; Esmaily, Masomeh; Darvishpour, Hojat

2015-01-01

Objectives: Headgears are among the effective orthodontic appliances to achieve treatment goals. Unilateral molar distal movement is sometimes needed during an orthodontic treatment, which can be achieved by an asymmetric headgear. Different unilateral headgears have been introduced. The main goal of this study was to analyze the force system of unilateral expanded outer bow asymmetric headgears by the finite element method (FEM). Materials and Methods: Six 3D finite element models of a mesiodistal slice of the maxilla containing upper first molars, their periodontal ligaments (PDLs), cancellous bone, cortical bone, and a cervical headgear with expanded outer bow attached to maxillary first molars were designed in SolidWorks 2010 and meshed in ANSYS Workbench ver. 12.1. The models were the same except for the degree of outer bow expansion. The outer bow ends were loaded with 2 N force. The distal driving force and the net moment were evaluated. Results: A decrease in the distalizing force in the normal side molar from 1.69 N to 1.37 N was shown by increasing the degree of unilateral expansion. At the same time, the force increased from 2.19 N to 2.49 N in the expanded side molar. A net moment increasing from 2.26 N.mm to 4.64 N.mm was also shown. Conclusion: Unilateral outer bow expansion can produce different distalizing forces in molars, which increase by increasing the expansion. PMID:26622282

Eosinophilic Esophagitis in Children and Adolescents with Abdominal Pain: Comparison with EoE-Dysphagia and Functional Abdominal Pain.

PubMed

Gunasekaran, Thirumazhisai; Prabhakar, Gautham; Schwartz, Alan; Gorla, Kiranmai; Gupta, Sandeep; Berman, James

2016-01-01

Aim. Compare EoE-AP with EoE-D for clinical, endoscopy (EGD), histology and outcomes and also with FAP-N. Method. Symptoms, physical findings, EGD, histology, symptom scores, and treatments were recorded for the three groups. Cluster analysis was done. Results. Dysphagia and abdominal pain were different in numbers but not statistically significant between EoE-AP and EoE-D. EGD, linear furrows, white exudates were more in the EoE-D and both combined were significant (p < 0.05). EoE-D, peak and mean eosinophils (p  0.06) and eosinophilic micro abscesses (p  0.001) were higher. Follow-Up. Based on single symptom, EoE-AP had 30% (p  0.25) improvement, EoE-D 86% (p < 0.001) and similar with composite score (p  0.57 and <0.001, resp.). Patients who had follow-up, EGD: 42.8% with EoE-AP and 77.8% with EoE-D, showed single symptom improvement and the eosinophil count fell from 38.5/34.6 (peak and mean) to 31.2/30.4 (p  0.70) and from 43.6/40.8 to 25.2/22.8 (p < 0.001), respectively. FAP-N patients had similar symptom improvement like EoE-D. Cluster Analysis. EoE-AP and FAP-N were similar in clinical features and response to treatment, but EoE-D was distinctly different from EoE-AP and FAP-N. Conclusion. Our study demonstrates that EoE-AP and EoE-D have different histology and outcomes. In addition, EoE-AP has clinical features similar to the FAP-N group.

Eosinophilic Esophagitis in Children and Adolescents with Abdominal Pain: Comparison with EoE-Dysphagia and Functional Abdominal Pain

PubMed Central

Gorla, Kiranmai; Gupta, Sandeep

2016-01-01

Aim. Compare EoE-AP with EoE-D for clinical, endoscopy (EGD), histology and outcomes and also with FAP-N. Method. Symptoms, physical findings, EGD, histology, symptom scores, and treatments were recorded for the three groups. Cluster analysis was done. Results. Dysphagia and abdominal pain were different in numbers but not statistically significant between EoE-AP and EoE-D. EGD, linear furrows, white exudates were more in the EoE-D and both combined were significant (p < 0.05). EoE-D, peak and mean eosinophils (p  0.06) and eosinophilic micro abscesses (p  0.001) were higher. Follow-Up. Based on single symptom, EoE-AP had 30% (p  0.25) improvement, EoE-D 86% (p < 0.001) and similar with composite score (p  0.57 and <0.001, resp.). Patients who had follow-up, EGD: 42.8% with EoE-AP and 77.8% with EoE-D, showed single symptom improvement and the eosinophil count fell from 38.5/34.6 (peak and mean) to 31.2/30.4 (p  0.70) and from 43.6/40.8 to 25.2/22.8 (p < 0.001), respectively. FAP-N patients had similar symptom improvement like EoE-D. Cluster Analysis. EoE-AP and FAP-N were similar in clinical features and response to treatment, but EoE-D was distinctly different from EoE-AP and FAP-N. Conclusion. Our study demonstrates that EoE-AP and EoE-D have different histology and outcomes. In addition, EoE-AP has clinical features similar to the FAP-N group. PMID:27610357

Feasibility of the simultaneous determination of polycyclic aromatic hydrocarbons based on two-dimensional fluorescence correlation spectroscopy

NASA Astrophysics Data System (ADS)

Yang, Renjie; Dong, Guimei; Sun, Xueshan; Yang, Yanrong; Yu, Yaping; Liu, Haixue; Zhang, Weiyu

2018-02-01

A new approach for quantitative determination of polycyclic aromatic hydrocarbons (PAHs) in environment was proposed based on two-dimensional (2D) fluorescence correlation spectroscopy in conjunction with multivariate method. 40 mixture solutions of anthracene and pyrene were prepared in the laboratory. Excitation-emission matrix (EEM) fluorescence spectra of all samples were collected. And 2D fluorescence correlation spectra were calculated under the excitation perturbation. The N-way partial least squares (N-PLS) models were developed based on 2D fluorescence correlation spectra, showing a root mean square error of calibration (RMSEC) of 3.50 μg L- 1 and root mean square error of prediction (RMSEP) of 4.42 μg L- 1 for anthracene and of 3.61 μg L- 1 and 4.29 μg L- 1 for pyrene, respectively. Also, the N-PLS models were developed for quantitative analysis of anthracene and pyrene using EEM fluorescence spectra. The RMSEC and RMSEP were 3.97 μg L- 1 and 4.63 μg L- 1 for anthracene, 4.46 μg L- 1 and 4.52 μg L- 1 for pyrene, respectively. It was found that the N-PLS model using 2D fluorescence correlation spectra could provide better results comparing with EEM fluorescence spectra because of its low RMSEC and RMSEP. The methodology proposed has the potential to be an alternative method for detection of PAHs in environment.

Depth of cure of resin composites: is the ISO 4049 method suitable for bulk fill materials?

PubMed

Flury, Simon; Hayoz, Stefanie; Peutzfeldt, Anne; Hüsler, Jürg; Lussi, Adrian

2012-05-01

To evaluate if depth of cure D(ISO) determined by the ISO 4049 method is accurately reflected with bulk fill materials when compared to depth of cure D(new) determined by Vickers microhardness profiles. D(ISO) was determined according to "ISO 4049; Depth of cure" and resin composite specimens (n=6 per group) were prepared of two control materials (Filtek Supreme Plus, Filtek Silorane) and four bulk fill materials (Surefil SDR, Venus Bulk Fill, Quixfil, Tetric EvoCeram Bulk Fill) and light-cured for either 10s or 20s. For D(new), a mold was filled with one of the six resin composites and light-cured for either 10 s or 20 s (n=22 per group). The mold was placed under a microhardness indentation device and hardness measurements (Vickers hardness, VHN) were made at defined distances, beginning at the resin composite that had been closest to the light-curing unit (i.e. at the "top") and proceeding toward the uncured resin composite (i.e. toward the "bottom"). On the basis of the VHN measurements, Vickers hardness profiles were generated for each group. D(ISO) varied between 1.76 and 6.49 mm with the bulk fill materials showing the highest D(ISO). D(new) varied between 0.2 and 4.0 mm. D(new) was smaller than D(ISO) for all resin composites except Filtek Silorane. For bulk fill materials the ISO 4049 method overestimated depth of cure compared to depth of cure determined by Vickers hardness profiles. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Experimental study of fusion neutron and proton yields produced by petawatt-laser-irradiated D₂-³He or CD₄-³He clustering gases.

PubMed

Bang, W; Barbui, M; Bonasera, A; Quevedo, H J; Dyer, G; Bernstein, A C; Hagel, K; Schmidt, K; Gaul, E; Donovan, M E; Consoli, F; De Angelis, R; Andreoli, P; Barbarino, M; Kimura, S; Mazzocco, M; Natowitz, J B; Ditmire, T

2013-09-01

We report on experiments in which the Texas Petawatt laser irradiated a mixture of deuterium or deuterated methane clusters and helium-3 gas, generating three types of nuclear fusion reactions: D(d,^{3}He)n, D(d,t)p, and ^{3}He(d,p)^{4}He. We measured the yields of fusion neutrons and protons from these reactions and found them to agree with yields based on a simple cylindrical plasma model using known cross sections and measured plasma parameters. Within our measurement errors, the fusion products were isotropically distributed. Plasma temperatures, important for the cross sections, were determined by two independent methods: (1) deuterium ion time of flight and (2) utilizing the ratio of neutron yield to proton yield from D(d,^{3}He)n and ^{3}He(d,p)^{4}He reactions, respectively. This experiment produced the highest ion temperature ever achieved with laser-irradiated deuterium clusters.

Data assimilation of non-conventional observations using GEOS-R flash lightning: 1D+4D-VAR approach vs. assimilation of images (Invited)

NASA Astrophysics Data System (ADS)

Navon, M. I.; Stefanescu, R.

2013-12-01

Previous assimilation of lightning used nudging approaches. We develop three approaches namely, 3D-VAR WRFDA and1D+nD-VAR (n=3,4) WRFDA . The present research uses Convective Available Potential Energy (CAPE) as a proxy between lightning data and model variables. To test performance of aforementioned schemes, we assess quality of resulting analysis and forecasts of precipitation compared to those from a control experiment and verify them against NCEP stage IV precipitation. Results demonstrate that assimilating lightning observations improves precipitation statistics during the assimilation window and for 3-7 h thereafter. The 1D+4D-VAR approach yielded the best performance significantly improving precipitation rmse errors by 25% and 27.5%,compared to control during the assimilation window for two tornadic test cases. Finally we propose a new approach to assimilate 2-D images of lightning flashes based on pixel intensity, mitigating dimensionality by a reduced order method.

Comparison of robotics, functional electrical stimulation, and motor learning methods for treatment of persistent upper extremity dysfunction after stroke: a randomized controlled trial.

PubMed

McCabe, Jessica; Monkiewicz, Michelle; Holcomb, John; Pundik, Svetlana; Daly, Janis J

2015-06-01

To compare response to upper-limb treatment using robotics plus motor learning (ML) versus functional electrical stimulation (FES) plus ML versus ML alone, according to a measure of complex functional everyday tasks for chronic, severely impaired stroke survivors. Single-blind, randomized trial. Medical center. Enrolled subjects (N=39) were >1 year postsingle stroke (attrition rate=10%; 35 completed the study). All groups received treatment 5d/wk for 5h/d (60 sessions), with unique treatment as follows: ML alone (n=11) (5h/d partial- and whole-task practice of complex functional tasks), robotics plus ML (n=12) (3.5h/d of ML and 1.5h/d of shoulder/elbow robotics), and FES plus ML (n=12) (3.5h/d of ML and 1.5h/d of FES wrist/hand coordination training). Primary measure: Arm Motor Ability Test (AMAT), with 13 complex functional tasks; secondary measure: upper-limb Fugl-Meyer coordination scale (FM). There was no significant difference found in treatment response across groups (AMAT: P≥.584; FM coordination: P≥.590). All 3 treatment groups demonstrated clinically and statistically significant improvement in response to treatment (AMAT and FM coordination: P≤.009). A group treatment paradigm of 1:3 (therapist/patient) ratio proved feasible for provision of the intensive treatment. No adverse effects. Severely impaired stroke survivors with persistent (>1y) upper-extremity dysfunction can make clinically and statistically significant gains in coordination and functional task performance in response to robotics plus ML, FES plus ML, and ML alone in an intensive and long-duration intervention; no group differences were found. Additional studies are warranted to determine the effectiveness of these methods in the clinical setting. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Continuous 28-day iododeoxyuridine infusion and hyperfractionated accelerated radiotherapy for malignant glioma: a phase I clinical study.

PubMed

Schulz, Craig A; Mehta, Minesh P; Badie, Benham; McGinn, Cornelius J; Robins, H Ian; Hayes, Lori; Chappell, Rick; Volkman, Jen; Binger, Kim; Arzoomanian, Rhoda; Simon, Kris; Alberti, Dona; Feierabend, Christine; Tutsch, Kendra D; Kunugi, Keith A; Wilding, George; Kinsella, Timothy J

2004-07-15

To investigate the maximal tolerated dose of a continuous 28-day iododeoxyuridine (IUdr) infusion combined with hyperfractionated accelerated radiotherapy (HART); to analyze the percentage of IUdr-thymidine replacement in peripheral granulocytes as a surrogate marker for IUdr incorporation into tumor cells; to measure the steady-state serum IUdr levels; and to assess the feasibility of continuous IUdr infusion and HART in the management of malignant glioma. Patients were required to have biopsy-proven malignant glioma. Patients received 100 (n = 4), 200 (n = 3), 300 (n = 3), 400 (n = 6), 500 (n = 4), 625 (n = 5), or 781 (n = 6) mg/m(2)/d of IUdr by continuous infusion for 28 days. HART was started 7 days after IUdr initiation. The total dose was 70 Gy (1.2 Gy b.i.d. for 25 days with a 10-Gy boost [2.0 Gy for 5 Saturdays]). Weekly assays were performed to determine the percentage of IUdr-DNA replacement in granulocytes and serum IUdr levels using standard high performance liquid chromatography methods. Standard Phase I toxicity methods were used. Between June 1994 and August 1999, 31 patients were enrolled. No patient had Grade 3 or worse HART toxicity. Grade 3 or greater IUdr toxicity predominantly included neutropenia (n = 3), thrombocytopenia (n = 3), and elevated liver function studies (n = 3). The maximal tolerated dose was 625 mg/m(2)/d. Thymidine replacement in the peripheral granulocytes peaked at 3 weeks and increased with the dose (maximal thymidine replacement 4.9%). The steady-state plasma IUdr level increased with the dose (maximum, 1.5 microM). In our study, continuous long-term IUdr i.v. infusion had a maximal tolerated dose of 625 mg/m(2)/d. Granulocyte incorporation data verified the concept that prolonged IUdr infusion results in IUdr-DNA replacement that corresponds to a high degree of cell labeling. IUdr steady-state plasma levels increased with increasing dose and attained levels needed for clinical radiosensitization. Continuous IUdr infusion and HART were both feasible and well tolerated.

Determination of cyclic volatile methylsiloxanes in biota with a purge and trap method.

PubMed

Kierkegaard, Amelie; Adolfsson-Erici, Margaretha; McLachlan, Michael S

2010-11-15

The three cyclic volatile methylsiloxanes (cVMS), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6), are recently identified environmental contaminants. Methods for the trace analysis of these chemicals in environmental matrices are required. A purge and trap method to prepare highly purified sample extracts with a low risk of sample contamination is presented. Without prior homogenization, the sample is heated in water, and the cVMS are purged from the slurry and trapped on an Isolute ENV+ cartridge. They are subsequently eluted with n-hexane and analyzed with GC/MS. The method was tested for eight different matrices including ragworms, muscle tissue from lean and lipid-rich fish, cod liver, and seal blubber. Analyte recoveries were consistent within and between matrices, averaging 79%, 68%, and 56% for D4, D5, and D6, respectively. Good control of blank levels resulted in limits of quantification of 1.5, 0.6, and 0.6 ng/g wet weight. The repeatability was 12% (D5) and 15% (D6) at concentrations 9 and 2 times above the LOQ. The method was applied to analyze cVMS in fish from Swedish lakes, demonstrating that contamination in fish as a result of long-range atmospheric transport is low as compared to contamination from local sources.

Self-rolling up micro 3D structures using temperature-responsive hydrogel sheet

NASA Astrophysics Data System (ADS)

Iwata, Y.; Miyashita, S.; Iwase, E.

2017-12-01

This paper proposes a micro self-folding using a self-rolling up deformation. In the fabrication method at micro scale, self-folding is an especially useful method of easily fabricating complex three-dimensional (3D) structures from engineered two-dimensional (2D) sheets. However, most self-folded structures are limited to 3D structures with a hollow region. Therefore, we made 3D structures with a small hollow region by self-rolling up a 2D sheet consisting of SU-8 and a temperature-responsive hybrid hydrogel of poly(N-isopropylacrylamide-co-acrylic acid) (pNIPAM-AAc). The temperature-responsive hydrogel can provide repetitive deformation, which is a good feature for micro soft robots or actuators, using hydrogel shrinking and swelling. Our micro self-rolling up method is a self-folding method for a 3D structure performed by rolling up a 2D flat sheet, like making a croissant, through continuous self-folding. We used our method to fabricate 3D structures with a small hollow region, such as cylindrical, conical, and croissant-like ellipsoidal structures, and 3D structures with a hollow region, such as spiral shapes. All the structures showed repetitive deformation, forward rolling up in 20 °C cold water and backward rolling up in 40 °C hot water. The results demonstrate that self-rolling up deformation can be useful in the field of micro soft devices.

Simultaneous determination of trimethylamine N-oxide, choline, betaine by UPLC-MS/MS in human plasma: An application in acute stroke patients.

PubMed

Yu, Weibang; Xu, Chuncao; Li, Guomin; Hong, Weipeng; Zhou, Ziyi; Xiao, Canxing; Zhao, Yuanqi; Cai, Yefeng; Huang, Min; Jin, Jing

2018-04-15

Trimethylamine-N-oxide (TMAO) is derived from the gut microbiome and tissues metabolism of dietary choline and betaine. These molecules are closely related to the development of cardiovascular and cerebrovascular diseases. A rapid, sensitive and accurate method has been developed and validated for the simultaneous determination of trimethylamine N-oxide (TMAO), choline and betaine in human plasma using d9-trimethylamine N-oxide (TMAO), d9-choline, d9-betaine as the internal standard (IS). After methanol precipitation with 10 μL plasma samples, the analytes were extracted and then separated on Amide column (2.1 × 100 mm, 1.7 μm, waters) with an isocratic elution program consisting of acetonitrile-water (containing 10 mM ammonium formate pH = 3.0) at a flow of 400 μL/min. The detection was achieved under the selected reaction monitoring (SRM) scan using positive electrospray ionization (ESI+) in 3 min. The mass transitions monitored were as follows: m/z 76.3 → 58.4 for TMAO, m/z 104.2 → 60.3 for choline, m/z 118.1 → 58.3 for betaine, m/z 85.1 → 66.3 for d9-TMAO, m/z 113.2 → 69.3 for d9-choline, and m/z 127.1 → 67.2 for d9-betaine, respectively. The method has been fully validated for specificity, lower limit of quantification, linearity, stability, intra- and inter-day accuracy and precision. This assay combines simple sample processing with a short run time and small plasma volumes, making it well suited for high-throughput routine clinical or research purposes. The newly developed method was successfully applied to the patients (n = 220) suffered from acute stroke, and the concentration of choline was firstly found to be closely related with the prognosis of these patients. Copyright © 2018 Elsevier B.V. All rights reserved.

Quantum approach to classical statistical mechanics.

PubMed

Somma, R D; Batista, C D; Ortiz, G

2007-07-20

We present a new approach to study the thermodynamic properties of d-dimensional classical systems by reducing the problem to the computation of ground state properties of a d-dimensional quantum model. This classical-to-quantum mapping allows us to extend the scope of standard optimization methods by unifying them under a general framework. The quantum annealing method is naturally extended to simulate classical systems at finite temperatures. We derive the rates to assure convergence to the optimal thermodynamic state using the adiabatic theorem of quantum mechanics. For simulated and quantum annealing, we obtain the asymptotic rates of T(t) approximately (pN)/(k(B)logt) and gamma(t) approximately (Nt)(-c/N), for the temperature and magnetic field, respectively. Other annealing strategies are also discussed.

Results of Sediment Sampling and Elutriate Testing at the Proposed Glovers Point Shallow Water Habitat Project Site

DTIC Science & Technology

2013-04-01

Aroclor1248 0.3 1.0 Endrin 0.003 0.1 PCB - Aroclor1268 0.3 1.0 Endrin Aldehyde 0.011 0.1 PCB - Aroclor1232 0.2 1.0 Endrin Ketone 0.006 0.1 PCB... aldehyde n.d. 0.0008 9.9 n.d. 0.009 50 Endrin ketone n.d. 0.003 9.9 n.d. NA 50 Heptachlor n.d. 0.002 5.1 n.d. NA 50 Heptachlor epoxide n.d. 0.0008...Endosulfan sulfate n.d. 0.002 n.d. 0.01 0.50 Endrin n.d. 0.004 n.d. 0.004 0.50 Endrin aldehyde n.d. 0.004 n.d. 0.08 1.00 Endrin ketone n.d. 0.006 n.d

3D Bioprinted Artificial Trachea with Epithelial Cells and Chondrogenic-Differentiated Bone Marrow-Derived Mesenchymal Stem Cells.

PubMed

Bae, Sang-Woo; Lee, Kang-Woog; Park, Jae-Hyun; Lee, JunHee; Jung, Cho-Rok; Yu, JunJie; Kim, Hwi-Yool; Kim, Dae-Hyun

2018-05-31

Tracheal resection has limited applicability. Although various tracheal replacement strategies were performed using artificial prosthesis, synthetic stents and tissue transplantation, the best method in tracheal reconstruction remains to be identified. Recent advances in tissue engineering enabled 3D bioprinting using various biocompatible materials including living cells, thereby making the product clinically applicable. Moreover, clinical interest in mesenchymal stem cell has dramatically increased. Here, rabbit bone marrow-derived mesenchymal stem cells (bMSC) and rabbit respiratory epithelial cells were cultured. The chondrogenic differentiation level of bMSC cultured in regular media (MSC) and that in chondrogenic media (d-MSC) were compared. Dual cell-containing artificial trachea were manufactured using a 3D bioprinting method with epithelial cells and undifferentiated bMSC (MSC group, n = 6) or with epithelial cells and chondrogenic-differentiated bMSC (d-MSC group, n = 6). d-MSC showed a relatively higher level of glycosaminoglycan (GAG) accumulation and chondrogenic marker gene expression than MSC in vitro. Neo-epithelialization and neo-vascularization were observed in all groups in vivo but neo-cartilage formation was only noted in d-MSC. The epithelial cells in the 3D bioprinted artificial trachea were effective in respiratory epithelium regeneration. Chondrogenic-differentiated bMSC had more neo-cartilage formation potential in a short period. Nevertheless, the cartilage formation was observed only in a localized area.

Pre-steady-state kinetic investigation of bypass of a bulky guanine lesion by human Y-family DNA polymerases.

PubMed

Tokarsky, E John; Gadkari, Varun V; Zahurancik, Walter J; Malik, Chanchal K; Basu, Ashis K; Suo, Zucai

2016-10-01

3-Nitrobenzanthrone (3-NBA), a byproduct of diesel exhaust, is highly present in the environment and poses a significant health risk. Exposure to 3-NBA results in formation of N-(2'-deoxyguanosin-8-yl)-3-aminobenzanthrone (dG C8- N -ABA ), a bulky DNA lesion that is of particular importance due to its mutagenic and carcinogenic potential. If not repaired or bypassed during genomic replication, dG C8- N -ABA can stall replication forks, leading to senescence and cell death. Here we used pre-steady-state kinetic methods to determine which of the four human Y-family DNA polymerases (hPolη, hPolκ, hPolι, or hRev1) are able to catalyze translesion synthesis of dG C8- N -ABA in vitro. Our studies demonstrated that hPolη and hPolκ most efficiently bypassed a site-specifically placed dG C8- N- ABA lesion, making them good candidates for catalyzing translesion synthesis (TLS) of this bulky lesion in vivo. Consistently, our publication (Biochemistry 53, 5323-31) in 2014 has shown that small interfering RNA-mediated knockdown of hPolη and hPolκ in HEK293T cells significantly reduces the efficiency of TLS of dG C8- N -ABA . In contrast, hPolι and hRev1 were severely stalled by dG C8- N -ABA and their potential role in vivo was discussed. Subsequently, we determined the kinetic parameters for correct and incorrect nucleotide incorporation catalyzed by hPolη at various positions upstream, opposite, and downstream from dG C8- N- ABA . Notably, nucleotide incorporation efficiency and fidelity both decreased significantly during dG C8- N -ABA bypass and the subsequent extension step, leading to polymerase pausing and error-prone DNA synthesis by hPolη. Furthermore, hPolη displayed nucleotide concentration-dependent biphasic kinetics at the two polymerase pause sites, suggesting that multiple enzyme•DNA complexes likely exist during nucleotide incorporation. Copyright © 2016 Elsevier B.V. All rights reserved.

Activation of D1 dopamine receptors induces emergence from isoflurane general anesthesia

PubMed Central

Taylor, Norman E.; Chemali, Jessica J.; Brown, Emery N.; Solt, Ken

2012-01-01

BACKGROUND A recent study showed that methylphenidate induces emergence from isoflurane anesthesia. Methylphenidate inhibits dopamine and norepinephrine reuptake transporters. The objective of this study was to test the hypothesis that selective dopamine receptor activation induces emergence from isoflurane anesthesia. METHODS In adult rats, we tested the effects of chloro-APB (D1 agonist) and quinpirole (D2 agonist) on time to emergence from isoflurane general anesthesia. We then performed a dose–response study to test for chloro-APB-induced restoration of righting during continuous isoflurane anesthesia. SCH-23390 (D1 antagonist) was used to confirm that the effects induced by chloro-APB are specifically mediated by D1 receptors. In a separate group of animals, spectral analysis was performed on surface electroencephalogram recordings to assess neurophysiological changes induced by chloro-APB and quinpirole during isoflurane general anesthesia. RESULTS Chloro-APB decreased median time to emergence from 330s to 50s. The median difference in time to emergence between the saline control group (n=6) and the chloro-APB group (n = 6) was 222s (95% CI: 77–534s, Mann-Whitney test). This difference was statistically significant (p = 0.0082). During continuous isoflurane anesthesia, chloro-APB dose-dependently restored righting (n = 6) and decreased electroencephalogram delta power (n = 4). These effects were inhibited by pretreatment with SCH-23390. Quinpirole did not restore righting (n = 6) and had no significant effect on the electroencephalogram (n = 4) during continuous isoflurane anesthesia. CONCLUSIONS Activation of D1 receptors by chloro-APB decreases time to emergence from isoflurane anesthesia, and produces behavioral and neurophysiological evidence of arousal during continuous isoflurane anesthesia. These findings suggest that selective activation of a D1 receptor-mediated arousal mechanism is sufficient to induce emergence from isoflurane general anesthesia. PMID:23221866

Statistical Moments in Variable Density Incompressible Mixing Flows

DTIC Science & Technology

2015-08-28

front tracking method: Verification and application to simulation of the primary breakup of a liquid jet . SIAM J. Sci. Comput., 33:1505–1524, 2011. [15... elliptic problem. In case of failure, Generalized Minimal Residual (GMRES) method [78] is used instead. Then update face velocities as follows: u n+1...of the ACM Solid and Physical Modeling Symposium, pages 159–170, 2008. [51] D. D. Joseph. Fluid dynamics of two miscible liquids with diffusion and

Multirate Integration Properties of Waveform Relaxation with Applications to Circuit Simulation and Parallel Computation

DTIC Science & Technology

1985-11-18

Greenberg and K. Sakallah at Digital Equipment Corporation, and C-F. Chen, L Nagel, and P. ,. Subrahmanyam at AT&T Bell Laboratories, both for providing...Circuit Theory McGraw-Hill, 1969. [37] R. Courant and D. Hilbert , Partial Differential Equations, Vol. 2 of Methods of Mathematical Physics...McGraw-Hill, N.Y., 1965. Page 161 [44) R. Courant and D. Hilbert , Partial Differential Equations, Vol. 2 of Methods of Mathematical Physics

Preconditioning 2D Integer Data for Fast Convex Hull Computations.

PubMed

Cadenas, José Oswaldo; Megson, Graham M; Luengo Hendriks, Cris L

2016-01-01

In order to accelerate computing the convex hull on a set of n points, a heuristic procedure is often applied to reduce the number of points to a set of s points, s ≤ n, which also contains the same hull. We present an algorithm to precondition 2D data with integer coordinates bounded by a box of size p × q before building a 2D convex hull, with three distinct advantages. First, we prove that under the condition min(p, q) ≤ n the algorithm executes in time within O(n); second, no explicit sorting of data is required; and third, the reduced set of s points forms a simple polygonal chain and thus can be directly pipelined into an O(n) time convex hull algorithm. This paper empirically evaluates and quantifies the speed up gained by preconditioning a set of points by a method based on the proposed algorithm before using common convex hull algorithms to build the final hull. A speedup factor of at least four is consistently found from experiments on various datasets when the condition min(p, q) ≤ n holds; the smaller the ratio min(p, q)/n is in the dataset, the greater the speedup factor achieved.

Four dimensional magnetic resonance imaging with retrospective k-space reordering: A feasibility study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Yilin; Yin, Fang-Fang; Cai, Jing, E-mail: jing.cai@duke.edu

Purpose: Current four dimensional magnetic resonance imaging (4D-MRI) techniques lack sufficient temporal/spatial resolution and consistent tumor contrast. To overcome these limitations, this study presents the development and initial evaluation of a new strategy for 4D-MRI which is based on retrospective k-space reordering. Methods: We simulated a k-space reordered 4D-MRI on a 4D digital extended cardiac-torso (XCAT) human phantom. A 2D echo planar imaging MRI sequence [frame rate (F) = 0.448 Hz; image resolution (R) = 256 × 256; number of k-space segments (N{sub KS}) = 4] with sequential image acquisition mode was assumed for the simulation. Image quality of themore » simulated “4D-MRI” acquired from the XCAT phantom was qualitatively evaluated, and tumor motion trajectories were compared to input signals. In particular, mean absolute amplitude differences (D) and cross correlation coefficients (CC) were calculated. Furthermore, to evaluate the data sufficient condition for the new 4D-MRI technique, a comprehensive simulation study was performed using 30 cancer patients’ respiratory profiles to study the relationships between data completeness (C{sub p}) and a number of impacting factors: the number of repeated scans (N{sub R}), number of slices (N{sub S}), number of respiratory phase bins (N{sub P}), N{sub KS}, F, R, and initial respiratory phase at image acquisition (P{sub 0}). As a proof-of-concept, we implemented the proposed k-space reordering 4D-MRI technique on a T2-weighted fast spin echo MR sequence and tested it on a healthy volunteer. Results: The simulated 4D-MRI acquired from the XCAT phantom matched closely to the original XCAT images. Tumor motion trajectories measured from the simulated 4D-MRI matched well with input signals (D = 0.83 and 0.83 mm, and CC = 0.998 and 0.992 in superior–inferior and anterior–posterior directions, respectively). The relationship between C{sub p} and N{sub R} was found best represented by an exponential function (C{sub P}=100(1−e{sup −0.18N{sub R}}), when N{sub S} = 30, N{sub P} = 6). At a C{sub P} value of 95%, the relative error in tumor volume was 0.66%, indicating that N{sub R} at a C{sub P} value of 95% (N{sub R,95%}) is sufficient. It was found that N{sub R,95%} is approximately linearly proportional to N{sub P} (r = 0.99), and nearly independent of all other factors. The 4D-MRI images of the healthy volunteer clearly demonstrated respiratory motion in the diaphragm region with minimal motion induced noise or aliasing. Conclusions: It is feasible to generate respiratory correlated 4D-MRI by retrospectively reordering k-space based on respiratory phase. This new technology may lead to the next generation 4D-MRI with high spatiotemporal resolution and optimal tumor contrast, holding great promises to improve the motion management in radiotherapy of mobile cancers.« less

Doubly 15N-substituted diazenylium: THz laboratory spectra and fractionation models

NASA Astrophysics Data System (ADS)

Dore, L.; Bizzocchi, L.; Wirström, E. S.; Degli Esposti, C.; Tamassia, F.; Charnley, S. B.

2017-07-01

Context. Isotopic fractionation in dense molecular cores has been suggested as a possible origin of large 14N/15N ratio variations in solar system materials. While chemical models can explain some observed variations with different fractionation patterns for molecules with -NH or -CN functional groups, they fail to reproduce the observed ratios in diazenylium (N2H+). Aims: Observations of doubly 15N-substituted species could provide important constraints and insights for theoretical chemical models of isotopic fractionation. However, spectroscopic data are very scarce. Methods: The rotational spectra of the fully 15N-substituted isopologues of the diazenylium ion, 15N2H+ and 15N2D+, have been investigated in the laboratory well into the THz region by using a source-modulation microwave spectrometer equipped with a negative glow discharge cell. An extended chemical reaction network has been used to estimate what ranges of 15N fractionation in doubly 15N-substituted species could be expected in the interstellar medium (ISM). Results: For each isotopologue of the H- and D-containing pair, nine rotational transitions were accurately measured in the frequency region 88 GHz-1.2 THz. The analysis of the spectrum provided very precise rest frequencies at millimeter and sub-millimeter wavelengths, useful for the radioastronomical identification of the rotational lines of 15N2H+ and 15N2D+ in the ISM.

Some Progress in Large-Eddy Simulation using the 3-D Vortex Particle Method

NASA Technical Reports Server (NTRS)

Winckelmans, G. S.

1995-01-01

This two-month visit at CTR was devoted to investigating possibilities in LES modeling in the context of the 3-D vortex particle method (=vortex element method, VEM) for unbounded flows. A dedicated code was developed for that purpose. Although O(N(sup 2)) and thus slow, it offers the advantage that it can easily be modified to try out many ideas on problems involving up to N approx. 10(exp 4) particles. Energy spectrums (which require O(N(sup 2)) operations per wavenumber) are also computed. Progress was realized in the following areas: particle redistribution schemes, relaxation schemes to maintain the solenoidal condition on the particle vorticity field, simple LES models and their VEM extension, possible new avenues in LES. Model problems that involve strong interaction between vortex tubes were computed, together with diagnostics: total vorticity, linear and angular impulse, energy and energy spectrum, enstrophy. More work is needed, however, especially regarding relaxation schemes and further validation and development of LES models for VEM. Finally, what works well will eventually have to be incorporated into the fast parallel tree code.

Determination of drug lipophilicity by phosphatidylcholine-modified microemulsion high-performance liquid chromatography.

PubMed

Xuan, Xueyi; Xu, Liyuan; Li, Liangxing; Gao, Chongkai; Li, Ning

2015-07-25

A new biomembrane-mimetic liquid chromatographic method using a C8 stationary phase and phosphatidylcholine-modified (PC-modified) microemulsion mobile phase was used to estimate unionized and ionized drugs lipophilicity expressed as an n-octanol/water partition coefficient (logP and logD). The introduction of PC into sodium dodecyl sulfate (SDS) microemulsion yielded a good correlation between logk and logD (R(2)=0.8). The optimal composition of the PC-modified microemulsion liquid chromatography (PC-modified MELC) mobile phase was 0.2% PC-3.0% SDS-6.0% n-butanol-0.8% ethyl acetate-90.0% water (pH 7.0) for neutral and ionized molecules. The interactions between the analytes and system described by this chromatographic method is more similar to biological membrane than the n-octanol/water partition system. The result in this paper suggests that PC-modified MELC can serve as a possible alternative to the shake-flask method for high-throughput unionized and ionized drugs lipophilicity determination and simulation of biological processes. Copyright © 2015 Elsevier B.V. All rights reserved.

Structural diversity of a series of terpyridyl carboxylate coordination polymers: Luminescent sensor and magnetic properties

NASA Astrophysics Data System (ADS)

Yuan, Fei; Yuan, Chun-Mei; Hu, Huai-Ming; Wang, Ting-Ting; Zhou, Chun-Sheng

2018-02-01

Eleven new coordination polymers, [Zn2(ctpy)2(HCOO)2]n·3nH2O (1), [Zn2(ctpy)2(HCOO)2(H2O)2]n·nH2O (2), [Zn2(ctpy)2(H2O)4]n·2n(CH3COO)·nH2O (3), [Zn2(ctpy)2(CH3COO)2]n·nH2O (4), [Zn(ctpy)2]n·nH2O (5), [Zn2(ctpy)2(Hidc)(H2O)2]n(6), [Cd2(ctpy)4]n(7), [Cd2(ctpy)2(Hidc)]n(8), [Co2(ctpy)2(HCOO)2(H2O)2]n·nH2O (9), [Co(ctpy)(DMF)(ox)0.5]n(10), [Co(ctpy)(ox)0.5]n(11) and the closely related compound [Zn(ctpy)(ox)0.5]n·0.5nH2O (12) (Hctpy = 4‧-carboxy-4,2‧:6‧,4‧‧-terpyridine, H2ox = oxalic acid and H3idc = imidazole-4,5-dicarboxylic acid) have been synthesized by hydro(solvo)thermal reaction of 4‧-carboxy-4,2‧:6‧,4‧‧-terpyridine with divalent metal salts and characterized by elemental analysis, IR spectra, single crystal X-ray diffraction. Compounds 1 and 4 have similar structure which demonstrate a two-fold interpenetrating 3D framework with a 3-connected utp topological net, which contains the same number of left and right-handed 21 helical chains. Compounds 2 and 9 are isostructural 2D layer with a 3-connected hcb topological net. Similar to 2, compound 3 also displays a 3-connected 2D hcb topological net. Compounds 5 and 10 are a 2D layer with a 4-connected sql topological net. Compound 6 shows a chiral 2D layer based on a 1D left- or right-handed helical chains, which are further extended into an achiral 2D + 2D→3D supramolecular network by hydrogen bonds with alternately arrangement. Compound 7 features an unusual 2-fold interpenetrating 3D coordination network which exhibits a new intriguing (3,5)-connected binodal topological net with the Schläfli symbol of (52·6)(53·63·73·8). Compound 8 shows a 2D→3D supramolecular structure based on (3,4)-connected 2D bilayers with the Schläfli symbol of (44·62). Compound 11 displays an unusual three-dimensional coordination network which exhibits an intriguing (3,8)-connected binodal new topological net with Schläfli symbol (42·62)2(42·623·83). Compound 12 features a two-fold interpenetrating (3,4)-connected 3D framework with the fsc topological net. Compounds 1-12 were obtained under similar reaction conditions. The diverse structures indicate that rational selection of the second ligand, metal salt, counter anion and solvent are good methods to further design metal-organic compounds with new structures and properties. Moreover, their thermal stabilities, photoluminescent and magnetic properties were also investigated. More importantly, compound 12 has been successfully applied in the detection of Fe3+ ion in DMF solutions and nitrobenzene and the possible detecting mechanism was also discussed.

IMPACT OF DIET AND/OR EXERCISE INTERVENTION ON INFRAPATELLAR FAT PAD MORPHOLOGY - SECONDARY ANALYSIS FROM THE INTENSIVE DIET AND EXERCISE FOR ARTHRITIS (IDEA) TRIAL

PubMed Central

Murillo, A. Pogacnik; Eckstein, F.; Wirth, W.; Beavers, D.; Loeser, R. F.; Nicklas, B. J.; Mihalko, S.L.; Miller, G.D.; Hunter, D.J.; Messier, S. P.

2017-01-01

Objectives The infrapatellar fat pad (IPFP) represents intra-articular adipose tissue that may contribute to intra-articular inflammation and pain by secretion of pro-inflammatory cytokines. Here we examined the impact of weight loss by diet and/or exercise interventions on IPFP volume. Methods Intensive Diet and Exercise for Arthritis (IDEA) was a single-blinded, single-center, 18-month, prospective, randomized controlled trial that enrolled 454 overweight and obese older adults with knee pain and radiographic osteoarthritis. Participants were randomized to 1 of 3 groups: exercise only control (E), diet-induced weight loss (D), and diet-induced weight loss + exercise (D+E). In a subsample (n=106; E: n=36; D: n=35; D+E: n=35), magnetic resonance images were acquired at baseline and 18-month follow-up, from which we analyzed IPFP volume, surface areas and thickness in this secondary analysis. Results Average weight loss in each group amounted to 1.0% in E, 10.5% in D, and 13.0% in D+E. A significant (p< 0.01) reduction in IPFP volume was observed in E (2.1%), D (4.0%) and D+E (5.2%). The IPFP volume loss in D+E was significantly greater than that in E (p<0.05) when not adjusting for parallel comparisons. Across intervention groups, there were significant correlations between IPFP volume change, individual weight loss (r=0.40), and change in total body fat mass (DXA; r=0.44; n=88) and in subcutaneous thigh fat area (CT; r=0.32; n=82). Conclusions As a potential link between obesity and knee OA, the IPFP was sensitive to intervention by diet and/or exercise, and its reduction was correlated with change in weight and body fat. PMID:28222422

Location of alkali metal binding sites in endothelin A selective receptor antagonists, cyclo(D-Trp-D-Asp-Pro-D-Val-Leu) and cyclo(D-Trp-D-Asp-Pro-D-Ile-Leu), from multistep collisionally activated decompositions.

PubMed

Ngoka, L C; Gross, M L

2000-02-01

We previously showed by using mass spectrometry that endothelin A selective receptor antagonists BQ123 and JKC301 form novel coordination compounds with sodium ions. This property may underlie the ability of an ET(A) antagonist to induce net tubular sodium reabsorption in the proximal tubule cells and reverse acute renal failure induced by severe ischemia. We have now defined the metal binding sites on BQ123 and JKC301 by subjecting the metal-containing peptides to multiple stages of collisionally activated decomposition (CAD) in an ion trap mass spectrometer. When submitted to low-energy CAD, the ring opens at the Asp-Pro amide bond. The metal ion, which bonds, inter alia, to the carbonyl oxygen of the proline residue, acts as a fixed charge site, and directs a charge-remote, sequence-specific fragmentation of the ring-opened peptide. Amino acid residues are sequentially cleaved from the C-terminal end, and the terminal aziridinone structure moves one step toward the N-terminus with each C-terminal amino acid residue removed. These observations are the basis of a new method to sequence cyclic peptides. Amino acid residues are observed as sets of three ions, a*(n)PD, b*(n)PD and c*(n)PD where n is the number of amino acid residues in the peptide. Copyright 2000 John Wiley & Sons, Ltd.

40 CFR 799.9510 - TSCA bacterial reverse mutation test.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Mutagenicity Test. Mutation Research. 31, 347-364 (1975). (2) Maron, D.M. and Ames, B.N. Revised Methods for the Salmonella Mutagenicity Test. Mutation Research. 113, 173-215 (1983). (3) Gatehouse, D., Haworth... Fluctuation Test to Detect Low Levels of Mutagens. Mutation Research. 38, 33-42 (1976). (10) Hubbard, S.A...

Nondestructive measurement of the refractive index distribution of a glass molded lens by two-wavelength wavefronts.

PubMed

Sugimoto, Tomohiro

2016-10-01

This paper presents a nondestructive and non-exact-index-matching method for measuring the refractive index distribution of a glass molded lens with high refractivity. The method measures two-wavelength wavefronts of a test lens immersed in a liquid with a refractive index dispersion different from that of the test lens and calculates the refractive index distribution by eliminating the refractive index distribution error caused by the shape error of the test lens. The estimated uncertainties of the refractive index distributions of test lenses with n_d≈1.77 and n_d≈1.85 were 1.9×10^-5  RMS and 2.4×10^-5  RMS, respectively. I validated the proposed method by evaluating the agreement between the estimated uncertainties and experimental values.

Computational 3D structures of drug-targeting proteins in the 2009-H1N1 influenza A virus

NASA Astrophysics Data System (ADS)

Du, Qi-Shi; Wang, Shu-Qing; Huang, Ri-Bo; Chou, Kuo-Chen

2010-01-01

The neuraminidase (NA) and M2 proton channel of influenza virus are the drug-targeting proteins, based on which several drugs were developed. However these once powerful drugs encountered drug-resistant problem to the H5N1 and H1N1 flu. To address this problem, the computational 3D structures of NA and M2 proteins of 2009-H1N1 influenza virus were built using the molecular modeling technique and computational chemistry method. Based on the models the structure features of NA and M2 proteins were analyzed, the docking structures of drug-protein complexes were computed, and the residue mutations were annotated. The results may help to solve the drug-resistant problem and stimulate designing more effective drugs against 2009-H1N1 influenza pandemic.

Annual Technical Report of the Materials Research Laboratory at Brown University, July 1, 1985-April 30, 1987.

DTIC Science & Technology

1987-04-30

compounds: Functional integral methods allow a starting point for calculations in which the important hybridization effects between localized core... Photoluminescence in (CdNiSC.’ Proceedings of the XVII International Conference on the Physics of Scmiconductor,. D. Chadi and \\k A. Harrison, Eds...Cd.M~n)Sc IFrom Photoluminescence %leas u remc-n ". ’:: ic, B L-S. (1986). V Sha,-’a. \\ F 0 .ecra. Jr, D H Ridgle\\. R Kcrsha\\#. K Dv-ight and A. \\kold

Darboux coordinates and instanton corrections in projective superspace

NASA Astrophysics Data System (ADS)

Crichigno, P. Marcos; Jain, Dharmesh

2012-10-01

By demanding consistency of the Legendre transform construction of hyperkähler metrics in projective superspace, we derive the expression for the Darboux coordinates on the hyperkähler manifold. We apply these results to study the Coulomb branch moduli space of 4D, {N}=2 super-Yang-Mills theory (SYM) on {{{R}}^3}× {S^1} , recovering the results by GMN. We also apply this method to study the electric corrections to the moduli space of 5D, {N}=1 SYM on {{{R}}^3}× {T^2} and give the Darboux coordinates explicitly.

[Comparison of the acrylamide level in microwaved popcorn with that of ordinarily heated one].

PubMed

Sun, Shiyu; Xia, Yongmei; Liu, Xuefeng; Hu, Xueyi

2007-03-01

To establish a method of examining acrylamide in cooked popcorn. Solid phase extraction/gas chromatography (SPE/GC) was established with N, N-dimethyl acrylamide as internal standard. The detection limit and the quantification limit were estimated at 3 microg/L and 10 microg/L, respectively, and the linear correlation coefficient was 0.9969. Seven commercial popcorn samples with different flavors were collected and tested in this paper. The RSD of acrylamide level of caramel sweet popcorn microwaved was 1.95 % (n = 6). When the commercial popcorns of caramel sweet and cream salted were microwaved (A and D) or conventional heated (A' and D'), the acrylamide levels reached [Am]A = 1017 microg/kg, [Am]D = 146.5 microg/kg, [Am]A, = 2206 microg/kg and [Am]D = 970.1 microg/kg, respectively. The microwaved popcorns tested are safer in general because the acrylamide level of them except that with high simple sugar content is obviously lower than that of ordinarily heated one.

Mechanical performance and parameter sensitivity analysis of 3D braided composites joints.

PubMed

Wu, Yue; Nan, Bo; Chen, Liang

2014-01-01

3D braided composite joints are the important components in CFRP truss, which have significant influence on the reliability and lightweight of structures. To investigate the mechanical performance of 3D braided composite joints, a numerical method based on the microscopic mechanics is put forward, the modeling technologies, including the material constants selection, element type, grid size, and the boundary conditions, are discussed in detail. Secondly, a method for determination of ultimate bearing capacity is established, which can consider the strength failure. Finally, the effect of load parameters, geometric parameters, and process parameters on the ultimate bearing capacity of joints is analyzed by the global sensitivity analysis method. The results show that the main pipe diameter thickness ratio γ, the main pipe diameter D, and the braided angle α are sensitive to the ultimate bearing capacity N.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Eric L.; Davis, Quincy C.; Morse, Michael D.

The abrupt onset of predissociation in the congested electronic spectra of jet-cooled VC, VN, and VS has been observed using resonant two-photon ionization spectroscopy. It is argued that because of the high density of electronic states in these molecules, the predissociation threshold occurs at the thermochemical threshold for the production of separated atoms in their ground electronic states. As a result, the measured threshold represents the bond dissociation energy. Using this method, bond dissociation energies of D{sub 0}(V C) = 4.1086(25) eV, D{sub 0}(V N) = 4.9968(20) eV, and D{sub 0}(V S) = 4.5353(25) eV are obtained. From these values,more » enthalpies of formation are derived as Δ{sub f,0K}H°(V C(g)) = 827.0 ± 8 kJ mol{sup −1}, Δ{sub f,0K}H°(V N(g)) = 500.9 ± 8 kJ mol{sup −1}, and Δ{sub f,0K}H°(V S(g)) = 349.3 ± 8 kJ mol{sup −1}. Using a thermochemical cycle and the well-known ionization energies of V, VC, and VN, our results also provide D{sub 0}(V{sup +}–C) = 3.7242(25) eV and D{sub 0}(V{sup +}–N) = 4.6871(20) eV. These values are compared to previous measurements and to computational results. The precision of these bond dissociation energies makes them good candidates for testing computational chemistry methods, particularly those that employ density functional theory.« less

Life-history traits and effective population size in species with overlapping generations revisited: the importance of adult mortality.

PubMed

Waples, R S

2016-10-01

The relationship between life-history traits and the key eco-evolutionary parameters effective population size (Ne) and Ne/N is revisited for iteroparous species with overlapping generations, with a focus on the annual rate of adult mortality (d). Analytical methods based on populations with arbitrarily long adult lifespans are used to evaluate the influence of d on Ne, Ne/N and the factors that determine these parameters: adult abundance (N), generation length (T), age at maturity (α), the ratio of variance to mean reproductive success in one season by individuals of the same age (φ) and lifetime variance in reproductive success of individuals in a cohort (Vk•). Although the resulting estimators of N, T and Vk• are upwardly biased for species with short adult lifespans, the estimate of Ne/N is largely unbiased because biases in T are compensated for by biases in Vk• and N. For the first time, the contrasting effects of T and Vk• on Ne and Ne/N are jointly considered with respect to d and φ. A simple function of d and α based on the assumption of constant vital rates is shown to be a robust predictor (R(2)=0.78) of Ne/N in an empirical data set of life tables for 63 animal and plant species with diverse life histories. Results presented here should provide important context for interpreting the surge of genetically based estimates of Ne that has been fueled by the genomics revolution.

Selective Complexation and Reactivity of Metallic Nitride and OxoMetallic Fullerenes with Lewis Acids and Use as an Effective Purification Method

PubMed Central

Stevenson, Steven; Mackey, Mary A.; Pickens, Jane E.; Stuart, Melissa A.; Confait, Bridget S.; Phillips, J. Paige

2009-01-01

Metallic nitride fullerenes (MNFs) and oxometallic fullerenes (OMFs) react quickly with an array of Lewis acids. Empty-cage fullerenes are largely unreactive under conditions used in this study. The reactivity order is Sc4O2@Ih-C80 > Sc3N@C78 > Sc3N@C68 > Sc3N@D5h-C80 > Sc3N@Ih-C80. Manipulations of Lewis acids, molar ratios and kinetic differences within the family of OMF and MNF metallofullerenes are demonstrated in a selective precipitation scheme, which can be used either alone for purifying Sc3N@Ih-C80 or combined with a final HPLC pass for Sc4O2@Ih-C80, Sc3N@D5h-C80, Sc3N@C68, or Sc3N@C78. The purification process is scalable. Analysis of experimental rate constants versus electrochemical band gap explains the order of reactivity among the OMF and MNFs. PMID:19911812

Investigation of the effect of mutations of rat albumin on the binding affinity to the alpha(4)beta(1) integrin antagonist, 4-[1-[3-chloro-4-[N'-(2-methylphenyl)ureido]phenylacetyl]-(4S)-fluoro-(2S)-pyrrolidine-2-yl]methoxybenzoic acid (D01-4582), using recombinant rat albumins.

PubMed

Ito, Takashi; Takahashi, Masayuki; Okazaki, Osamu; Sugiyama, Yuichi

2010-08-02

The authors reported previously rat strain differences in plasma protein binding to alpha(4)beta(1) antagonist D01-4582, resulting in a great strain difference in its pharmacokinetics (19-fold differences in the AUC). The previous study suggested that amino acid changes of V238L and/or T293I in albumin reduced the binding affinity. In order to elucidate the relative significance of these mutations, an expression system was developed to obtain recombinant rat albumins (rRSA) using Pichia pastoris, followed by a binding analysis of four rRSAs by the ultracentrifugation method. The equilibrium dissociation constant (K(d)) of wild-type rRSA was 210 nM, while K(d) of rRSA that carried both V238L and T293I mutations was 974 nM. K(d) of artificial rRSA that carried only V238L was 426 nM, and K(d) of artificial rRSA that carried only T293I was 191 nM. These results suggested that V238L would be more important in the alteration of K(d). However, since none of the single mutations were sufficient to explain the reduction of affinity, the possibility was also suggested that T293I interacted cooperatively to reduce the binding affinity of rat albumin to D01-4582. Further investigation is required to elucidate the mechanism of the possible cooperative interaction.

Synthesis, X-ray diffraction method, spectroscopic characterization (FT-IR, 1H and 13C NMR), antimicrobial activity, Hirshfeld surface analysis and DFT computations of novel sulfonamide derivatives

NASA Astrophysics Data System (ADS)

Demircioğlu, Zeynep; Özdemir, Fethi Ahmet; Dayan, Osman; Şerbetçi, Zafer; Özdemir, Namık

2018-06-01

Synthesized compounds of N-(2-aminophenyl)benzenesulfonamide 1 and (Z)-N-(2-((2-nitrobenzylidene)amino)phenyl)benzenesulfonamide 2 were characterized by antimicrobial activity, FT-IR, 1H and 13C NMR. Two new Schiff base ligands containing aromatic sulfonamide fragment of (Z)-N-(2-((3-nitrobenzylidene)amino)phenyl)benzenesulfonamide 3 and (Z)-N-(2-((4-nitrobenzylidene)amino)phenyl)benzenesulfonamide 4 were synthesized and investigated by spectroscopic techniques including 1H and 13C NMR, FT-IR, single crystal X-ray diffraction, Hirshfeld surface, theoretical method analyses and by antimicrobial activity. The molecular geometry obtained from the X-ray structure determination was optimized Density Functional Theory (DFT/B3LYP) method with the 6-311++G(d,p) basis set in ground state. From the optimized geometry of the molecules of 3 and 4, the geometric parameters, vibrational wavenumbers and chemical shifts were computed. The optimized geometry results, which were well represented the X-ray data, were shown that the chosen of DFT/B3LYP 6-311G++(d,p) was a successful choice. After a successful optimization, frontier molecular orbitals, chemical activity, non-linear optical properties (NLO), molecular electrostatic mep (MEP), Mulliken population method, natural population analysis (NPA) and natural bond orbital analysis (NBO), which cannot be obtained experimentally, were calculated and investigated.

A reliable and controllable graphene doping method compatible with current CMOS technology and the demonstration of its device applications

NASA Astrophysics Data System (ADS)

Kim, Seonyeong; Shin, Somyeong; Kim, Taekwang; Du, Hyewon; Song, Minho; Kim, Ki Soo; Cho, Seungmin; Lee, Sang Wook; Seo, Sunae

2017-04-01

The modulation of charge carrier concentration allows us to tune the Fermi level (E F) of graphene thanks to the low electronic density of states near the E F. The introduced metal oxide thin films as well as the modified transfer process can elaborately maneuver the amounts of charge carrier concentration in graphene. The self-encapsulation provides a solution to overcome the stability issues of metal oxide hole dopants. We have manipulated systematic graphene p-n junction structures for electronic or photonic application-compatible doping methods with current semiconducting process technology. We have demonstrated the anticipated transport properties on the designed heterojunction devices with non-destructive doping methods. This mitigates the device architecture limitation imposed in previously known doping methods. Furthermore, we employed E F-modulated graphene source/drain (S/D) electrodes in a low dimensional transition metal dichalcogenide field effect transistor (TMDFET). We have succeeded in fulfilling n-type, ambipolar, or p-type field effect transistors (FETs) by moving around only the graphene work function. Besides, the graphene/transition metal dichalcogenide (TMD) junction in either both p- and n-type transistor reveals linear voltage dependence with the enhanced contact resistance. We accomplished the complete conversion of p-/n-channel transistors with S/D tunable electrodes. The E F modulation using metal oxide facilitates graphene to access state-of-the-art complimentary-metal-oxide-semiconductor (CMOS) technology.

The D 2 k R 4 invariants of mathcal{N} = 8 supergravity

NASA Astrophysics Data System (ADS)

Freedman, Daniel Z.; Tonni, Erik

2011-04-01

The existence of a linearized SUSY invariant for mathcal{N} = 8 supergravity whose gravitational components are usually called R 4 was established long ago by on-shell super-space arguments. Superspace and string theory methods have also established analogous higher dimensional D 2 k R 4 invariants. However, very little is known about the SUSY completions of these operators which involve other fields of the theory. In this paper we find the detailed component expansion of the linearized R 4 invariant starting from the corresponding superamplitude which generates all component matrix elements of the operator. It is then quite straightforward to extend results to the entire set of D 2 k R 4 operators.

A novel surface registration algorithm with biomedical modeling applications.

PubMed

Huang, Heng; Shen, Li; Zhang, Rong; Makedon, Fillia; Saykin, Andrew; Pearlman, Justin

2007-07-01

In this paper, we propose a novel surface matching algorithm for arbitrarily shaped but simply connected 3-D objects. The spherical harmonic (SPHARM) method is used to describe these 3-D objects, and a novel surface registration approach is presented. The proposed technique is applied to various applications of medical image analysis. The results are compared with those using the traditional method, in which the first-order ellipsoid is used for establishing surface correspondence and aligning objects. In these applications, our surface alignment method is demonstrated to be more accurate and flexible than the traditional approach. This is due in large part to the fact that a new surface parameterization is generated by a shortcut that employs a useful rotational property of spherical harmonic basis functions for a fast implementation. In order to achieve a suitable computational speed for practical applications, we propose a fast alignment algorithm that improves computational complexity of the new surface registration method from O(n3) to O(n2).

Model-independent determination of the astrophysical S factor in laser-induced fusion plasmas

NASA Astrophysics Data System (ADS)

Lattuada, D.; Barbarino, M.; Bonasera, A.; Bang, W.; Quevedo, H. J.; Warren, M.; Consoli, F.; De Angelis, R.; Andreoli, P.; Kimura, S.; Dyer, G.; Bernstein, A. C.; Hagel, K.; Barbui, M.; Schmidt, K.; Gaul, E.; Donovan, M. E.; Natowitz, J. B.; Ditmire, T.

2016-04-01

In this work, we present a new and general method for measuring the astrophysical S factor of nuclear reactions in laser-induced plasmas and we apply it to :mmultiscripts>(d ,n )3He . The experiment was performed with the Texas Petawatt Laser, which delivered 150-270 fs pulses of energy ranging from 90 to 180 J to D2 or CD4 molecular clusters (where D denotes 2H ) . After removing the background noise, we used the measured time-of-flight data of energetic deuterium ions to obtain their energy distribution. We derive the S factor using the measured energy distribution of the ions, the measured volume of the fusion plasma, and the measured fusion yields. This method is model independent in the sense that no assumption on the state of the system is required, but it requires an accurate measurement of the ion energy distribution, especially at high energies, and of the relevant fusion yields. In the :mmultiscripts>(d ,n )3He and 3He(d ,p )4He cases discussed here, it is very important to apply the background subtraction for the energetic ions and to measure the fusion yields with high precision. While the available data on both ion distribution and fusion yields allow us to determine with good precision the S factor in the d +d case (lower Gamow energies), for the d +3He case the data are not precise enough to obtain the S factor using this method. Our results agree with other experiments within the experimental error, even though smaller values of the S factor were obtained. This might be due to the plasma environment differing from the beam target conditions in a conventional accelerator experiment.

Model-independent determination of the astrophysical S factor in laser-induced fusion plasmas

DOE PAGES

Lattuada, D.; Barbarino, M.; Bonasera, A.; ...

2016-04-19

In this paper, we present a new and general method for measuring the astrophysical S factor of nuclear reactions in laser-induced plasmas and we apply it to 2H(d,n) 3He. The experiment was performed with the Texas Petawatt Laser, which delivered 150–270 fs pulses of energy ranging from 90 to 180 J to D 2 or CD 4 molecular clusters (where D denotes 2H). After removing the background noise, we used the measured time-of-flight data of energetic deuterium ions to obtain their energy distribution. We derive the S factor using the measured energy distribution of the ions, the measured volume ofmore » the fusion plasma, and the measured fusion yields. This method is model independent in the sense that no assumption on the state of the system is required, but it requires an accurate measurement of the ion energy distribution, especially at high energies, and of the relevant fusion yields. In the 2H(d,n) 3He and 3He(d,p) 4He cases discussed here, it is very important to apply the background subtraction for the energetic ions and to measure the fusion yields with high precision. While the available data on both ion distribution and fusion yields allow us to determine with good precision the S factor in the d+d case (lower Gamow energies), for the d+ 3He case the data are not precise enough to obtain the S factor using this method. Our results agree with other experiments within the experimental error, even though smaller values of the S factor were obtained. This might be due to the plasma environment differing from the beam target conditions in a conventional accelerator experiment.« less

A probability score for preoperative prediction of type 2 diabetes remission following RYGB surgery

PubMed Central

Still, Christopher D.; Wood, G. Craig; Benotti, Peter; Petrick, Anthony T.; Gabrielsen, Jon; Strodel, William E.; Ibele, Anna; Seiler, Jamie; Irving, Brian A.; Celaya, Melisa P.; Blackstone, Robin; Gerhard, Glenn S.; Argyropoulos, George

2014-01-01

BACKGROUND Type 2 diabetes (T2D) is a metabolic disease with significant medical complications. Roux-en-Y gastric bypass (RYGB) surgery is one of the few interventions that remit T2D in ~60% of patients. However, there is no accurate method for predicting preoperatively the probability for T2D remission. METHODS A retrospective cohort of 2,300 RYGB patients at Geisinger Clinic was used to identify 690 patients with T2D and complete electronic data. Two additional T2D cohorts (N=276, and N=113) were used for replication at 14 months following RYGB. Kaplan-Meier analysis was used in the primary cohort to create survival curves until remission. A Cox proportional hazards model was used to estimate the hazard ratios on T2D remission. FINDINGS Using 259 preoperative clinical variables, four (use of insulin, age, HbA1c, and type of antidiabetic medication) were sufficient to develop an algorithm that produces a type 2 diabetes remission (DiaRem) score over five years. The DiaRem score spans from 0 to 22 and was divided into five groups corresponding to five probability-ranges for T2D remission: 0–2 (88%–99%), 3–7 (64%–88%), 8–12 (23%–49%), 13–17 (11%–33%), 18–22 (2%–16%). The DiaRem scores in the replication cohorts, as well as under various definitions of diabetes remission, conformed to the DiaRem score of the primary cohort. INTERPRETATION The DiaRem score is a novel preoperative method for predicting the probability (from 2% to 99%) for T2D remission following RYGB surgery. FUNDING This research was supported by the Geisinger Health System and the National Institutes of Health. PMID:24579062

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lattuada, D.; Barbarino, M.; Bonasera, A.

In this paper, we present a new and general method for measuring the astrophysical S factor of nuclear reactions in laser-induced plasmas and we apply it to 2H(d,n) 3He. The experiment was performed with the Texas Petawatt Laser, which delivered 150–270 fs pulses of energy ranging from 90 to 180 J to D 2 or CD 4 molecular clusters (where D denotes 2H). After removing the background noise, we used the measured time-of-flight data of energetic deuterium ions to obtain their energy distribution. We derive the S factor using the measured energy distribution of the ions, the measured volume ofmore » the fusion plasma, and the measured fusion yields. This method is model independent in the sense that no assumption on the state of the system is required, but it requires an accurate measurement of the ion energy distribution, especially at high energies, and of the relevant fusion yields. In the 2H(d,n) 3He and 3He(d,p) 4He cases discussed here, it is very important to apply the background subtraction for the energetic ions and to measure the fusion yields with high precision. While the available data on both ion distribution and fusion yields allow us to determine with good precision the S factor in the d+d case (lower Gamow energies), for the d+ 3He case the data are not precise enough to obtain the S factor using this method. Our results agree with other experiments within the experimental error, even though smaller values of the S factor were obtained. This might be due to the plasma environment differing from the beam target conditions in a conventional accelerator experiment.« less

Differential Benefit of Statin in Secondary Prevention of Acute Myocardial Infarction according to the Level of Triglyceride and High Density Lipoprotein Cholesterol

PubMed Central

Kim, Kyung Hwan; Kim, Cheol Hwan; Ahn, Youngkeun; Kim, Young Jo; Cho, Myeong Chan; Kim, Wan; Kim, Jong Jin

2016-01-01

Background and Objectives The differential benefit of statin according to the state of dyslipidemia has been sparsely investigated. We sought to address the efficacy of statin in secondary prevention of myocardial infarction (MI) according to the level of triglyceride and high density lipoprotein cholesterol (HDL-C) on admission. Subjects and Methods Acute MI patients (24653) were enrolled and the total patients were divided according to level of triglyceride and HDL-C on admission: group A (HDL-C≥40 mg/dL and triglyceride<150 mg/dL; n=11819), group B (HDL-C≥40 mg/dL and triglyceride≥150 mg/dL; n=3329), group C (HDL-C<40 mg/dL and triglyceride<150 mg/dL; n=6062), and group D (HDL-C<40 mg/dL & triglyceride≥150 mg/dL; n=3443). We evaluated the differential efficacy of statin according to the presence or absence of component of dyslipidemia. The primary end points were major adverse cardiac events (MACE) for 2 years. Results Statin therapy significantly reduced the risk of MACE in group A (hazard ratio=0.676; 95% confidence interval: 0.582-0.785; p<0.001). However, the efficacy of statin was not prominent in groups B, C, or D. In a propensity-matched population, the result was similar. In particular, the benefit of statin in group A was different compared with group D (interaction p=0.042) Conclusion The benefit of statin in patients with MI was different according to the presence or absence of dyslipidemia. In particular, because of the insufficient benefit of statin in patients with MI and dyslipidemia, a different lipid-lowering strategy is necessary in these patients. PMID:27275169

The X40×10 Halogen Bonding Benchmark Revisited: Surprising Importance of (n-1)d Subvalence Correlation.

PubMed

Kesharwani, Manoj K; Manna, Debashree; Sylvetsky, Nitai; Martin, Jan M L

2018-03-01

We have re-evaluated the X40×10 benchmark for halogen bonding using conventional and explicitly correlated coupled cluster methods. For the aromatic dimers at small separation, improved CCSD(T)-MP2 "high-level corrections" (HLCs) cause substantial reductions in the dissociation energy. For the bromine and iodine species, (n-1)d subvalence correlation increases dissociation energies and turns out to be more important for noncovalent interactions than is generally realized; (n-1)sp subvalence correlation is much less important. The (n-1)d subvalence term is dominated by core-valence correlation; with the smaller cc-pVDZ-F12-PP and cc-pVTZ-F12-PP basis sets, basis set convergence for the core-core contribution becomes sufficiently erratic that it may compromise results overall. The two factors conspire to generate discrepancies of up to 0.9 kcal/mol (0.16 kcal/mol RMS) between the original X40×10 data and the present revision.

A Method for Direct Determination of Real Height from Virtual Height Data for the Auroral Region of the Ionosphere.

DTIC Science & Technology

1979-11-14

except when n is an integer we write Eq. (13) in the form jj-g) (14) whose inverse transform is readily calculated as 2 d2 ’ F u(k)= H- J (F) dF (15...as "i(s) 1 s2 (45) r(+1 -2 s 7 The inverse transform of Eq. (45) is then _I_ d fF I H’ (F)dF (46) -J ’-(1+*) d Fr 1 r(l-A) which may be written as F

Genre Matters: A Comparative Study on the Entertainment Effects of 3D in Cinematic Contexts

NASA Astrophysics Data System (ADS)

Ji, Qihao; Lee, Young Sun

2014-09-01

Built upon prior comparative studies of 3D and 2D films, the current project investigates the effects of 2D and 3D on viewers' perception of enjoyment, narrative engagement, presence, involvement, and flow across three movie genres (Action/fantasy vs. Drama vs. Documentary). Through a 2 by 3 mixed factorial design, participants (n = 102) were separated into two viewing conditions (2D and 3D) and watched three 15-min film segments. Result suggested both visual production methods are equally efficient in terms of eliciting people's enjoyment, narrative engagement, involvement, flow and presence, no effects of visual production method was found. In addition, through examining the genre effects in both 3D and 2D conditions, we found that 3D works better for action movies than documentaries in terms of eliciting viewers' perception of enjoyment and presence, similarly, it improves views' narrative engagement for documentaries than dramas substantially. Implications and limitations are discussed in detail.

Rapid enantiomeric separation and simultaneous determination of phenethylamines by ultra high performance liquid chromatography with fluorescence and mass spectrometric detection: application to the analysis of illicit drugs distributed in the Japanese market and biological samples.

PubMed

Inagaki, Shinsuke; Hirashima, Haruo; Taniguchi, Sayuri; Higashi, Tatsuya; Min, Jun Zhe; Kikura-Hanajiri, Ruri; Goda, Yukihiro; Toyo'oka, Toshimasa

2012-12-01

A rapid enantiomeric separation and simultaneous determination method based on ultra high performance liquid chromatography (UHPLC) was developed for phenethylamine-type abused drugs using (R)-(-)-4-(N,N-dimethylaminosulfonyl)-7-(3-isothiocyanatopyrrolidin-1-yl)-2,1,3-benzoxadiazole ((R)-(-)-DBD-Py-NCS) as the chiral fluorescent derivatization reagent. The derivatives were rapidly enantiomerically separated by reversed-phase UHPLC using a column of 2.3-µm octadecylsilica (ODS) particles by isocratic elution with water-methanol or water-acetonitrile systems as the mobile phase. The proposed method was applied to the analysis of products containing illicit drugs distributed in the Japanese market. Among the products, 1-(3,4-methylenedioxyphenyl)butan-2-amine (BDB) and 1-(2-methoxy4,5-methylenedioxyphenyl)propan-2-amine (MMDA-2) were detected in racemic form. Furthermore, the method was successfully applied to the analysis of hair specimens from rats that were continuously dosed with diphenyl(pyrrolidin-2-yl)methanol (D2PM). Using UHPLC-fluorescence (FL) detection, (R)- and (S)-D2PM from hair specimens were enantiomerically separated and detected with high sensitivity. The detection limits of (R)- and (S)-D2PM were 0.12 and 0.21 ng/mg hair, respectively (signal-to-noise ratio (S/N) = 3). Copyright © 2012 John Wiley & Sons, Ltd.

2D-2D stacking of graphene-like g-C3N4/Ultrathin Bi4O5Br2 with matched energy band structure towards antibiotic removal

NASA Astrophysics Data System (ADS)

Ji, Mengxia; Di, Jun; Ge, Yuping; Xia, Jiexiang; Li, Huaming

2017-08-01

A novel visible-light-driven 2D-2D graphene-like g-C3N4/ultrathin Bi4O5Br2 photocatalyst was prepared via a facile solvothermal method in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br) for the first time. FT-IR, XPS and TEM analysis results demonstrated the successful introduction of the 2D graphene-like g-C3N4 material to the Bi4O5Br2 system. DRS and BET analysis results indicated the existence of the g-C3N4 could lead to the broaden absorption edge and larger surface area of the ultrathin Bi4O5Br2 nanosheets. The electrochemical analysis implied a fast transfer of the interfacial electrons and low recombination rate of photogenerated charge carriers in g-C3N4/Bi4O5Br2, which could be assigned to the sufficient and tight contact between ultrathin Bi4O5Br2 and graphene-like g-C3N4. The quinolone antibiotic ciprofloxacin (CIP) was chosen as the target pollutant to evaluate the photocatalytic performance of the as-prepared samples under visible light irradiation. 1 wt% g-C3N4/Bi4O5Br2 composite exhibited the highest photocatalytic degradation performance among all of the as-prepared photocatalysts. The enhancement of photocatalytic activity was attributed to the maximum contact between graphene-like g-C3N4 and ultrathin Bi4O5Br2 material with matched energy band structure, which enable the efficient charge seperation. A possible photocatalytic mechanism also was proposed.

Supramolecular assemblies of nucleoside functionalized carbon nanotubes: synthesis, film preparation, and properties.

PubMed

Micoli, Alessandra; Turco, Antonio; Araujo-Palomo, Elsie; Encinas, Armando; Quintana, Mildred; Prato, Maurizio

2014-04-25

Nucleoside-functionalized multi-walled carbon nanotubes (N-MWCNTs) were synthesized and characterized. A self-organization process using hydrogen bonding interactions was then used for the fabrication of self-assembled N-MWCNTs films free of stabilizing agents, polymers, or surfactants. Membranes were produced by using a simple water-dispersion-based vacuum-filtration method. Hydrogen-bond recognition was confirmed by analysis with IR spectroscopy and TEM images. Restoration of the electronic conduction properties in the N-MWCNTs membranes was performed by removing the organic portion by thermal treatment under an argon atmosphere to give d-N-MWCNTs. Electrical conductivity and thermal gravimetric analysis (TGA) measurements confirmed the efficiency of the annealing process. Finally, oxidative biodegradation of the films N-MWCNTs and d-N-MWCNTs was performed by using horseradish peroxidase (HRP) and low concentrations of H2 O2 . Our results confirm that functional groups play an important role in the biodegradation of CNT by HRP: N-MWCNTs films were completely biodegraded, whereas for d-N-MWCNTs films no degradation was observed, showing that the pristine CNT undergoes minimal enzyme-catalyzed oxidation This novel methodology offers a straightforward supramolecular strategy for the construction of conductive and biodegradable carbon nanotube films. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The impact of flattening-filter-free beam technology on 3D conformal RT

PubMed Central

2013-01-01

Background The removal of the flattening filter (FF) leads to non-uniform fluence distribution with a considerable increase in dose rate. It is possible to adapt FFF beams (flattening-filter-free) in 3D conformal radiation therapy (3D CRT) by using field in field techniques (FiF). The aim of this retrospective study is to clarify whether the quality of 3D CRT plans is influenced by the use of FFF beams. Method This study includes a total of 52 CT studies of RT locations that occur frequently in clinical practice. Dose volume targets were provided for the PTV of breast (n=13), neurocranium (n=11), lung (n=7), bone metastasis (n=10) and prostate (n=11) in line with ICRU report 50/62. 3D CRT planning was carried out using FiF methods. Two clinically utilized photon energies are used for a Siemens ARTISTE linear accelerator in FFF mode at 7MVFFF and 11MVFFF as well as in FF mode at 6MVFF and 10MVFF. The plan quality in relation to the PTV coverage, OAR (organs at risk) and low dose burden as well as the 2D dosimetric verification is compared with FF plans. Results No significant differences were found between FFF and FF plans in the mean dose for the PTV of breast, lung, spine metastasis and prostate. The low dose parameters V5Gy and V10Gy display significant differences for FFF and FF plans in some subgroups. The DVH analysis of the OAR revealed some significant differences. Significantly more fields (1.9 – 4.5) were necessary in the use of FFF beams for each location (p<0.0001) in order to achieve PTV coverage. All the tested groups displayed significant increases (1.3 – 2.2 times) in the average number of necessary MU with the use of FFF beams (p<0.001). Conclusions This study has shown that the exclusive use of a linear accelerator in FFF mode is feasible in 3D CRT. It was possible to realize RT plans in comparable quality in typical cases of clinical radiotherapy. The 2D dosimetric validation of the modulated fields verified the dose calculation and thus the correct reproduction of the characteristic FFF parameters in the planning system that was used. PMID:23725479

Integration into Civil Airspace Airworthiness and Safety

DTIC Science & Technology

2003-09-02

Integration into Civil Airspace Airworthiness and Safety 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER......into civil airspace lPurpose : n to explore and propose French process and means for integrating UAV into civil airspace. lMethod based on : n first

Screening for Novel Germline Rare Mutations Associated with Aggressive Prostate Cancer

DTIC Science & Technology

2014-10-01

Schmidt S., Peshkin L., et al. A method and server for predicting damaging missense mutations. Nat Methods. 7, 248-249 (2010). Akbari MR, Trachtenberg...Inst. 2012 Aug 1;104(16):1260-2. Epub 2012 Jul 9. Castro E. G.C.L., Olmos D., et al. Correlation of germ-line BRCA2 mutations with aggressive...prostate cancer. Clin Cancer Res. 16, 2115-2121 (2010). 20    Hammer GE, Gonzalez F, Champsaur M, Cado D, Shastri N. The aminopeptidase ERAAP shapes the

Micromethod for phosphonoformate inhibition assay of hepatitis B viral DNA polymerase.

PubMed

Lin, H J; Wu, P C; Lai, C L; Chak, W

1984-04-01

A micromethod for the specific measurement of hepatitis B viral DNA polymerase in serum is presented, based on the phosphonoformate inhibition assay (J Med Virol 12: 61-70, 1983). In the micromethod, sample volume is reduced to 120 microL and the ultracentrifugation step is eliminated. The method allows good discrimination between serum infected with hepatitis B virus and uninfected serum. The cutoff value for rate of nucleotide incorporation, based on assays of 41 serum specimens negative for hepatitis B serological markers, was about 15 nU/L (90th percentile). Serum containing hepatitis B surface and antigens exhibited rates of phosphonoformate-inhibitive nucleotide incorporation of 150 (SD 150) nU/L, with an upper 90th percentile range of 17 to 667 nU/L (n = 41). The micromethod makes use of commercially available [32P]dCTP (specific activity about 7000 kCi/mol). 125I-labeled dCTP was found to be unsuitable for this assay. Human DNA polymerases in serum are detected by this method but are excluded from the phosphonoformate-inhibitive fraction.

Grouped and Multistep Nanoheteroepitaxy: Toward High-Quality GaN on Quasi-Periodic Nano-Mask.

PubMed

Feng, Xiaohui; Yu, Tongjun; Wei, Yang; Ji, Cheng; Cheng, Yutian; Zong, Hua; Wang, Kun; Yang, Zhijian; Kang, Xiangning; Zhang, Guoyi; Fan, Shoushan

2016-07-20

A novel nanoheteroepitaxy method, namely, the grouped and multistep nanoheteroepitaxy (GM-NHE), is proposed to attain a high-quality gallium nitride (GaN) epilayer by metal-organic vapor phase epitaxy. This method combines the effects of sub-100 nm nucleation and multistep lateral growth by using a low-cost but unique carbon nanotube mask, which consists of nanoscale growth windows with a quasi-periodic 2D fill factor. It is found that GM-NHE can facilely reduce threading dislocation density (TDD) and modulate residual stress on foreign substrate without any regrowth. As a result, high-quality GaN epilayer is produced with homogeneously low TDD of 4.51 × 10(7) cm(-2) and 2D-modulated stress, and the performance of the subsequent 410 nm near-ultraviolet light-emitting diode is greatly boosted. In this way, with the facile fabrication of nanomask and the one-off epitaxy procedure, GaN epilayer is prominently improved with the assistance of nanotechnology, which demonstrates great application potential for high-efficiency TDD-sensitive optoelectronic and electronic devices.

Quantitative analysis of weak interactions by Lattice energy calculation, Hirshfeld surface and DFT studies of sulfamonomethoxine

NASA Astrophysics Data System (ADS)

Patel, Kinjal D.; Patel, Urmila H.

2017-01-01

Sulfamonomethoxine, 4-Amino-N-(6-methoxy-4-pyrimidinyl) benzenesulfonamide (C11H12N4O3S), is investigated by single crystal X-ray diffraction technique. Pair of N-H⋯N and C-H⋯O intermolecular interactions along with π···π interaction are responsible for the stability of the molecular packing of the structure. In order to understand the nature of the interactions and their quantitative contributions towards the crystal packing, the 3D Hirshfeld surface and 2D fingerprint plot analysis are carried out. PIXEL calculations are performed to determine the lattice energies correspond to intermolecular interactions in the crystal structure. Ab initio quantum chemical calculations of sulfamonomethoxine (SMM) have been performed by B3LYP method, using 6-31G** basis set with the help of Schrodinger software. The computed geometrical parameters are in good agreement with the experimental data. The Mulliken charge distribution, calculated using B3LYP method to confirm the presence of electron acceptor and electron donor atoms, responsible for intermolecular hydrogen bond interactions hence the molecular stability.

Novel method for the determination of average molecular weight of natural polymers based on 2D DOSY NMR and chemometrics: Example of heparin.

PubMed

Monakhova, Yulia B; Diehl, Bernd W K; Do, Tung X; Schulze, Margit; Witzleben, Steffen

2018-02-05

Apart from the characterization of impurities, the full characterization of heparin and low molecular weight heparin (LMWH) also requires the determination of average molecular weight, which is closely related to the pharmaceutical properties of anticoagulant drugs. To determine average molecular weight of these animal-derived polymer products, partial least squares regression (PLS) was utilized for modelling of diffused-ordered spectroscopy NMR data (DOSY) of a representative set of heparin (n=32) and LMWH (n=30) samples. The same sets of samples were measured by gel permeation chromatography (GPC) to obtain reference data. The application of PLS to the data led to calibration models with root mean square error of prediction of 498Da and 179Da for heparin and LMWH, respectively. The average coefficients of variation (CVs) did not exceed 2.1% excluding sample preparation (by successive measuring one solution, n=5) and 2.5% including sample preparation (by preparing and analyzing separate samples, n=5). An advantage of the method is that the sample after standard 1D NMR characterization can be used for the molecular weight determination without further manipulation. The accuracy of multivariate models is better than the previous results for other matrices employing internal standards. Therefore, DOSY experiment is recommended to be employed for the calculation of molecular weight of heparin products as a complementary measurement to standard 1D NMR quality control. The method can be easily transferred to other matrices as well. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of clonazepam in a tablet dosage form using smallbore HPLC.

PubMed

Spell, J C; Stewart, J T

1998-11-01

A stability indicating, reversed phase high-performance liquid chromatographic method utilizing a smallbore HPLC column has been developed for the determination of clonazepam in a commercial tablet dosage form. The use of a small bore column results in a substantial solvent savings, as well as a greater mass sensitivity, especially in the identification of degradation peaks in a chromatogram. The method involves ultraviolet detection at 254 nm and utilized a 150 x 3.0 mm i.d. column packed with 3 microm octyldecylsilane particles with a mobile phase of water methanol acetonitrile (40:30:30, v/v/v) at a flow rate of 400 microl min(-1) at ambient temperature, with and without the use of 1,2-dichlorobenzene as the internal standard. The current USP method for the analysis of clonazepam using a 300 x 3.9 mm i.d. conventional octyldecylsilane column was utilized as a comparison to the smallbore method. The retention times for clonazepam and the internal standard on the 3.0 mm i.d. column were 4.0 and 12.5 min, respectively. The intra- and interday RSDs on the 3.0 mm i.d. column were < 0.55% (n =4) using the internal standard, and < 0.19% (n = 4) without the internal standard at the lower limit of the standard curve, 50 microg ml(-1) and had a limit of detection of 24 ng ml(-1). The assay using the 3.0 mm i.d. column was shown to be suitable for measuring clonazepam in a tablet dosage form.

Theoretical Studies of the Glycosidation of 2-O-Substituted 5-Fluorouracil: N-Regioselective Synthesis with the Phase-Transfer-Catalysis Method.

PubMed

Wang, Yi-Gui; Barnes, Ericka C

2017-11-22

The observed N-regioselective glycosidation of 2-O-substituted 5-fluorouracil (5-FU) via the phase-transfer-catalysis (PTC) method was investigated computationally. The Gibbs free energy reaction barrier of the N-reaction between the 5-FU anion and 1-bromo-1-deoxy-2,3,4,6-tetra-O-acetyl-α-d-glucopyranose was computed at the MP2/6-311++G(2d,p)//B3LYP/6-31+G* level. The calculated transition states were, in general, quite "loose", with the ambident reaction sites at the N3- or O4-positions on 5-FU located approximately 2.0 Å from the anomeric carbon. With the S N 2 mechanism, the formation of β-glycosides was explained by the characteristics of transition states, and the N-regioselectivity was explained by three considerations: (1) the conformations of initial complexes and the structural requirement of the reactions; (2) the formation of an ionic pair between nBu 4 N + and 2-O-substituted 5-FU anions; and (3) the thermodynamic conversion of O-glycosides to N-glycosides. The reactions between the oxocarbenium ion and the 2-O-substituted 5-FU anions (the fast step of S N 1 mechanism) were also examined at the same level of theory. Because there were no "promoters" to extract Br in the PTC method, the S N 1 mechanism might have an unfavorably high barrier to produce oxocarbenium ion. However, both the formation of β-glycosides and the experimentally observed N-regioselectivity could also be explained by the S N 1 mechanism: The former was explained by the neighboring group participation, and the latter was explained by the formation of ionic pairs between nBu 4 N + and 2-O-substituted 5-FU anions. The formation of ionic pairs possibly changed the diffusion-controlled mechanism into an activation-controlled mechanism. Two factors were demonstrated by Marcus theory to play an important role for the experimentally observed N-resioselectivity in the PTC method: (1) the thermodynamic stability of N-products over O-products; (2) the formation of ionic pair between nBu 4 N + and 2-O-substituted 5-FU anions.

Electrochemical impedance based chiral analysis of anti-ascorbutic drug: l-Ascorbic acid and d-ascorbic acid using C-dots decorated conductive polymer nano-composite electrode.

PubMed

Pandey, Indu; Kant, Rama

2016-03-15

Clinical manifestations owing to l-ascorbic acid for scurvy as comparison to d-ascorbic acid and challenges of chiral purity are overcome by using chiral selective conductive polymer nanocomposite which mimics antibodies and enzymes. A novel chiral selective imprinted polyaniline-ferrocene-sulfonic acid film has been electrochemically fabricated on C-dots modified pencil graphite electrode. The performance of the obtained l-ascorbic acid or d-ascorbic acid chiral selective sensor was investigated by electrochemical impedance spectroscopy, cyclic and differential pulse voltammetry. The surface characteristics of the C-dots, chiral sensor before and after the de-doping of chiral d- and l-ascorbic acid were characterized by scanning electron microscopy, Raman spectroscopy and X-ray diffraction spectroscopy. Excellent recognition results were obtained by difference in electron transfer resistance. The proposed chiral sensor is capable of measuring d-ascorbic acid or l-ascorbic acid in aqueous as well as in real and commercial samples within the range of 0.020-0.187 nM and 0.003-0.232 nM with detection limit of 0.00073 nM and 0.00016 nM, respectively. The proposed method has also been examined for the chiral selective recognition of ascorbic acid isomers (d- and l-) quantitatively, in complicated matrices of real samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Cyclin d1 expression in odontogenic cysts.

PubMed

Taghavi, Nasim; Modabbernia, Shirin; Akbarzadeh, Alireza; Sajjadi, Samad

2013-01-01

In the present study expression of cyclin D1 in the epithelial lining of odontogenic keratocyst, radicular cyst, dentigerous cyst and glandular odontogenic cyst was investigated to compare proliferative activity in these lesions. Immunohistochemical staining of cyclin D1 on formalin-fixed, paraffin-embedded tissue sections of odontogenic keratocysts (n=23), dentigerous cysts (n=20), radicular cysts (n=20) and glandular odontogenic cysts (n=5) was performed by standard EnVision method. Then, slides were studied to evaluate the following parameters in epithelial lining of cysts: expression, expression pattern, staining intensity and localization of expression. The data analysis showed statistically significant difference in cyclin D1 expression in studied groups (p < 0.001). Assessment of staining intensity and staining pattern showed more strong intensity and focally pattern in odontogenic keratocysts, but difference was not statistically significant among groups respectively (p=0.204, 0.469). Considering expression localization, cyclin D1 positive cells in odontogenic keratocysts and dentigerous cysts were frequently confined in parabasal layer, different from radicular cysts and glandular odontogenic cysts. The difference was statistically significant (p < 0.01). Findings showed higher expression of cyclin D1 in parabasal layer of odontogenic keratocyst and the entire cystic epithelium of glandular odontogenic cysts comparing to dentigerous cysts and radicular cysts, implying the possible role of G1-S cell cycle phase disturbances in the aggressiveness of odontogenic keratocyst and glandular odontogenic cyst.

Darboux points and integrability of homogeneous Hamiltonian systems with three and more degrees of freedom. Nongeneric cases

NASA Astrophysics Data System (ADS)

Przybylska, M.

2009-06-01

In this paper the problem of classification of integrable natural Hamiltonian systems with n degrees of freedom given by a Hamilton function, which is the sum of the standard kinetic energy and a homogeneous polynomial potential V of degree k > 2, is investigated. It is assumed that the potential is not generic. Except for some particular cases a potential V is not generic if it admits a nonzero solution of equation V'( d) = 0. The existence of such a solution gives very strong integrability obstructions obtained in the frame of the Morales-Ramis theory. This theory also gives additional integrability obstructions which have the form of restrictions imposed on the eigenvalues ( λ 1, …, λ n ) of the Hessian matrix V″( d) calculated at a nonzero d ∈ ℂ n satisfying V'( d) = d. In our previous work we showed that for generic potentials some universal relations between ( λ 1, …, λ n ) calculated at various solutions of V' ( d) = d exist. These relations allow one to prove that the number of potentials satisfying the necessary conditions for the integrability is finite. The main aim of this paper was to show that relations of such forms also exist for nongeneric potentials. We show their existence and derive them for the case n = k = 3 applying the multivariable residue calculus. We demonstrate the strength of the results analyzing in details the nongeneric cases for n = k = 3. Our analysis covers all the possibilities and we distinguish those cases where known methods are too weak to decide if the potential is integrable or not. Moreover, for n = k = 3, thanks to this analysis, a three-parameter family of potentials integrable or superintegrable with additional polynomial first integrals which seemingly can be of an arbitrarily high degree with respect to the momenta was distinguished.

Effects of a Thin Ru-Doped PVP Interface Layer on Electrical Behavior of Ag/n-Si Structures

NASA Astrophysics Data System (ADS)

Badali, Yosef; Nikravan, Afsoun; Altındal, Şemsettin; Uslu, İbrahim

2018-03-01

The aim of this study is to improve the electrical property of Ag/n-Si metal-semiconductor (MS) structure by growing an Ru-doped PVP interlayer between Ag and n-Si using electrospinning technique. To illustrate the utility of the Ru-doped PVP interface layer, current-voltage (I-V) characteristics of Ag/n-Si (MS) and Ag/Ru-doped PVP/n-Si metal-polymer-semiconductor (MPS) structures was carried out. In addition, the main electrical parameters of the fabricated Ag/Ru-doped PVP/n-Si structures were investigated as a function of frequency and electric field using impedance spectroscopy method (ISM). The capacitance-voltage (C-V) plot showed an anomalous peak in the depletion region due to the special density distribution of interface traps/states (D it /N ss) and interlayer. Both the values of series resistance (R s) and N ss were drawn as a function of voltage and frequency between 0.5 kHz and 5 MHz at room temperature and they had a peak behavior in the depletion region. Some important parameters of the sample such as the donor concentration atoms (N D), Fermi energy (E F ), thickness of the depletion region (W D), barrier height (Φ B0 ) and R s were determined from the C -2 versus V plot for each frequency. The values of N D , W D , Φ B0 and R s were changed from 1 × 1015 cm-3, 9.61 × 10-5 cm, 0.94 eV and 19,055 Ω (at 0.5 kHz) to 0.13 × 1015 cm-3, 27.4 × 10-4 cm, 1.04 eV and 70 Ω (at 5 MHz), respectively. As a result of the experiments, it is observed that the change in electrical parameters becomes more effective at lower frequencies due to the N ss and their relaxation time (τ), dipole and surface polarizations.

Effects of a Thin Ru-Doped PVP Interface Layer on Electrical Behavior of Ag/n-Si Structures

NASA Astrophysics Data System (ADS)

Badali, Yosef; Nikravan, Afsoun; Altındal, Şemsettin; Uslu, İbrahim

2018-07-01

The aim of this study is to improve the electrical property of Ag/n-Si metal-semiconductor (MS) structure by growing an Ru-doped PVP interlayer between Ag and n-Si using electrospinning technique. To illustrate the utility of the Ru-doped PVP interface layer, current-voltage ( I-V) characteristics of Ag/n-Si (MS) and Ag/Ru-doped PVP/n-Si metal-polymer-semiconductor (MPS) structures was carried out. In addition, the main electrical parameters of the fabricated Ag/Ru-doped PVP/n-Si structures were investigated as a function of frequency and electric field using impedance spectroscopy method (ISM). The capacitance-voltage ( C-V) plot showed an anomalous peak in the depletion region due to the special density distribution of interface traps/states ( D it /N ss) and interlayer. Both the values of series resistance ( R s) and N ss were drawn as a function of voltage and frequency between 0.5 kHz and 5 MHz at room temperature and they had a peak behavior in the depletion region. Some important parameters of the sample such as the donor concentration atoms ( N D), Fermi energy ( E F ), thickness of the depletion region ( W D), barrier height ( Φ B0 ) and R s were determined from the C - 2 versus V plot for each frequency. The values of N D , W D , Φ B0 and R s were changed from 1 × 1015 cm-3, 9.61 × 10-5 cm, 0.94 eV and 19,055 Ω (at 0.5 kHz) to 0.13 × 1015 cm-3, 27.4 × 10-4 cm, 1.04 eV and 70 Ω (at 5 MHz), respectively. As a result of the experiments, it is observed that the change in electrical parameters becomes more effective at lower frequencies due to the N ss and their relaxation time ( τ), dipole and surface polarizations.

The Guanine Cation Radical: Investigation of Deprotonation States by ESR and DFT

PubMed Central

Adhikary, Amitava; Kumar, Anil; Becker, David; Sevilla, Michael D.

2008-01-01

This work reports ESR studies that identify the favored site of deprotonation of the guanine cation radical (G•+) in an aqueous medium at 77 K. Using ESR and UV-visible spectroscopy, one-electron oxidized guanine is investigated in frozen aqueous D2O solutions of 2′-deoxyguanosine (dGuo) at low temperatures at various pHs at which the guanine cation, G•+ (pH 3–5), singly deprotonated species, G(-H)• (pH 7–9) and doubly deprotonated species, G(-2H)•− (pH>11) are found. C-8-deuteration of dGuo to give 8-D-dGuo removes the major proton hyperfine coupling at C-8. This isolates the anisotropic nitrogen couplings for each of the three species and aids our analyses. These anisotropic nitrogen couplings were assigned to specific nitrogen sites by use of 15N substituted derivatives at N1, N2 N3 atoms in dGuo. Both ESR and UV-visible spectra are reported for each of the species: G•+, G(-H)•, and G(-2H)•−. The experimental anisotropic ESR hyperfine couplings are compared to those obtained from DFT calculations for the various tautomers of G(-H)•. Using the B3LYP/6–31G(d) method, the geometries and energies of G•+ and its singly deprotonated state in its two tautomeric forms, G(N1-H)• and G(N2-H)•, were investigated. In a non-hydrated state G(N2-H)• is found to be more stable than G(N1-H)• but on hydration with 7 water molecules G(N1-H)• is found to be more stable than G(N2-H)•. The theoretically calculated hyperfine coupling constants (HFCC) of G•+, G(N1-H)• and G(-2H)•− match the experimentally observed HFCCs best on hydration with 7 or more waters. For G(-2H)•−, the hyperfine coupling constant (HFCC) at the exocyclic nitrogen atom (N2) is especially sensitive to the number of hydrating water molecules; good agreement with experiment is not obtained until 9 or 10 waters of hydration are included. PMID:17125389

Comparative Effects of Nitrogen Fertigation and Granular Fertilizer Application on Growth and Availability of Soil Nitrogen during Establishment of Highbush Blueberry

PubMed Central

Bryla, David R.; Machado, Rui M. A.

2011-01-01

A 2-year study was done to compare the effects of nitrogen (N) fertigation and granular fertilizer application on growth and availability of soil N during establishment of highbush blueberry (Vaccinium corymbosum L. “Bluecrop”). Treatments included four methods of N application (weekly fertigation, split fertigation, and two non-fertigated controls) and four levels of N fertilizer (0, 50, 100, and 150 kg·ha−1 N). Fertigation treatments were irrigated by drip and injected with a liquid urea solution; weekly fertigation was applied once a week from leaf emergence to 60 d prior to the end of the season while split fertigation was applied as a triple-split from April to June. Non-fertigated controls were fertilized with granular ammonium sulfate, also applied as a triple-split, and irrigated by drip or microsprinklers. Weekly fertigation produced the smallest plants among the four fertilizer application methods at 50 kg·ha−1 N during the first year after planting but the largest plants at 150 kg·ha−1 N in both the first and second year. The other application methods required less N to maximize growth but were less responsive than weekly fertigation to additional N fertilizer applications. In fact, 44–50% of the plants died when granular fertilizer was applied at 150 kg·ha−1 N. By comparison, none of the plants died with weekly fertigation. Plant death with granular fertilizer was associated with high ammonium ion concentrations (up to 650 mg·L−1) and electrical conductivity (>3 dS·m−1) in the soil solution. Early results indicate that fertigation may be less efficient (i.e., less plant growth per unit of N applied) at lower N rates than granular fertilizer application but is also safer (i.e., less plant death) and promotes more growth when high amounts of N fertilizer is applied. PMID:22639596

Comparative Effects of Nitrogen Fertigation and Granular Fertilizer Application on Growth and Availability of Soil Nitrogen during Establishment of Highbush Blueberry.

PubMed

Bryla, David R; Machado, Rui M A

2011-01-01

A 2-year study was done to compare the effects of nitrogen (N) fertigation and granular fertilizer application on growth and availability of soil N during establishment of highbush blueberry (Vaccinium corymbosum L. "Bluecrop"). Treatments included four methods of N application (weekly fertigation, split fertigation, and two non-fertigated controls) and four levels of N fertilizer (0, 50, 100, and 150 kg·ha(-1) N). Fertigation treatments were irrigated by drip and injected with a liquid urea solution; weekly fertigation was applied once a week from leaf emergence to 60 d prior to the end of the season while split fertigation was applied as a triple-split from April to June. Non-fertigated controls were fertilized with granular ammonium sulfate, also applied as a triple-split, and irrigated by drip or microsprinklers. Weekly fertigation produced the smallest plants among the four fertilizer application methods at 50 kg·ha(-1) N during the first year after planting but the largest plants at 150 kg·ha(-1) N in both the first and second year. The other application methods required less N to maximize growth but were less responsive than weekly fertigation to additional N fertilizer applications. In fact, 44-50% of the plants died when granular fertilizer was applied at 150 kg·ha(-1) N. By comparison, none of the plants died with weekly fertigation. Plant death with granular fertilizer was associated with high ammonium ion concentrations (up to 650 mg·L(-1)) and electrical conductivity (>3 dS·m(-1)) in the soil solution. Early results indicate that fertigation may be less efficient (i.e., less plant growth per unit of N applied) at lower N rates than granular fertilizer application but is also safer (i.e., less plant death) and promotes more growth when high amounts of N fertilizer is applied.

Survey on the prevention and incidence of haemolytic disease of the newborn in Italy

PubMed Central

Bennardello, Francesco; Curciarello, Giuseppe

2013-01-01

Background In 2010, the Italian Society of Immunohaematology and Transfusion Medicine (SIMTI) carried out a survey of the incidence of haemolytic disease of the newborn (HDN) and the prevention of HDN caused by anti-Rh(D) in Italian Transfusion Structures (TS). Materials and methods A questionnaire divided into the following five sections was administered: (i) types of services provided and maintenance of legally required registers, (ii) immunoprophylaxis (IP), (iii) red cell typing and searches for irregular antibodies, (iv) evaluation of foetal-maternal haemorrhage (FMH), and (v) incidence of HDN in 2010. Of the 280 TS sent the questionnaire, 176 (63%) replied. Results A HDN register was available in 55.5% of the TS (n =91). Immunoprophylaxis with a dose of anti-D IgG was given to all Rh(D) negative and Rh(D) variant puerpera with Rh(D) positive newborns: in more than 93% of cases the dose was between 1,500 IU (300 μg) and 1,250 IU (250 μg). Antenatal IP between the 25th and 28th week was proposed by 42 TS (26%). Seventy percent of the TS (n =115) did not make any evaluation of FMH. The number of births surveyed in 2010 was 203,384, the number of Rh(D) negative pregnancies was 13,569, while anti-D antibodies were present in 245 pregnancies. There were 111 cases of HDN due to anti Rh(D) incompatibility and in 40 of these, intrauterine transfusion (n =8) or exchange transfusion (n =32) was necessary. In 94 cases HDN was due to other irregular antibodies: in 4 of these cases intrauterine transfusion was needed and in 11 other recourse was made of exchange transfusion. Finally, there were 1,456 newborns with ABO HDN of whom 13 underwent exchange transfusion. Discussion The data collected give a picture of the incidence of HDN in Italy and of the methods of managing IP and could form the basis for an update of the SIMTI recommendations on the management and prevention of this disease. PMID:23867179

Development of an ultra performance LC/MS method to quantify cisplatin 1,2 intrastrand guanine-guanine adducts

PubMed Central

Baskerville-Abraham, Irene M.; Boysen, Gunnar; Troutman, J. Mitchell; Mutlu, Esra; Collins, Leonard; deKrafft, Kathryn E.; Lin, Wenbin; King, Candice; Chaney, Stephen G.; Swenberg, James A.

2009-01-01

Platinum chemotherapeutic agents have been widely used in the treatment of cancer. Cisplatin was the first of the platinum based chemotherapeutic agents and therefore has been extensively studied as an anti-tumor agent since the late 1960s. Because this agent forms several DNA adducts, a highly sensitive and specific quantitative assay is needed to correlate the molecular dose of individual adducts with the effects of treatment. An ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) assay for quantification of 1,2 guanine-guanine intrastrand cisplatin adducts [CP-d(GpG)], using 15N10 CP-d(GpG) as an internal standard, was developed. The internal standard was characterized by MS/MS and its concentration was validated by ICP-MS. Samples containing CP-d(GpG) in DNA were purified by enzyme hydrolysis , centrifugal filtration and HPLC with fraction collection prior to quantification by UPLC-MS/MS in the selective reaction monitoring (SRM) mode (m/z 412.5→248.1 for CP-d(GpG); m/z 417.5→253.1 for [15N10] CP-d(GpG)). Recovery of standards was >90% and quantification was unaffected by increasing concentrations of calf thymus DNA. This method utilizes 25 μg of DNA per injection. The limit of quantification was 3 fmol or 3.7 adducts per 108 nucleotides, which approaches the sensitivity of the 32P postlabeling method for this adduct. These data suggested that this method is suitable for in vitro and in vivo assessment of CP-d(GpG) adducts formed by cisplatin and carboplatin. Subsequently the method was applied to studies using ovarian carcinoma cell lines and C57/BL6 mice to illustrate that this method is capable of quantifying CP-d(GpG) adducts using biologically relevant systems and doses. The development of biomarkers to determine tissue-specific molecular dosimetry during treatment will lead to a more complete understanding of both therapeutic and adverse effects of cisplatin and carboplatin. This will support the refinement of therapeutic regimes and appropriate individualized treatment protocols. PMID:19323581

Dispensable role of myeloid differentiation primary response gene 88 (MyD88) and MyD88-dependent toll-like receptors (TLRs) in a murine model of osteoarthritis.

PubMed

Nasi, Sonia; Ea, Hang-Korng; Chobaz, Véronique; van Lent, Peter; Lioté, Frédéric; So, Alexander; Busso, Nathalie

2014-07-01

The aim of our study was to evaluate the role of cell-membrane expressed TLRs and the signaling molecule MyD88 in a murine model of OA induced by knee menisectomy (surgical partial removal of the medial meniscus [MNX]). OA was induced in 8-10weeks old C57Bl/6 wild-type (WT) female (n=7) mice and in knockout (KO) TLR-1 (n=7), -2 (n=8), -4 (n=9) -6 (n=5), MyD88 (n=8) mice by medial menisectomy, using the sham-operated contralateral knee as a control. Cartilage destruction and synovial inflammation were evaluated by knee joint histology using the OARSI scoring method. Apoptotic chondrocytes and cartilage metabolism (collagen II synthesis and MMP-mediated aggrecan degradation) were analyzed using immunohistochemistry. Operated knees exhibited OA features at 8weeks post-surgery compared to sham-operated ones. In menisectomized TLR-1, -2, -4, and -6 deficient mice, cartilage lesions, synovial inflammation and cartilage metabolism were similar to that in operated WT mice. Accordingly, using the same approach, we found no significant protection in MyD88-deficient mice in terms of OA progression as compared to WT littermates. Deficiency of TLRs or their signalling molecule MyD88 did not impact on the severity of experimental OA. Our results demonstrate that MyD88-dependent TLRs are not involved in this murine OA model. Moreover, the dispensable role of MyD88, which is also an adaptor for IL-1 receptor signaling, suggests that IL-1 is not a key mediator in the development of OA. This latter hypothesis is strengthened by the lack of efficiency of IL-1β antagonist in the treatment of OA. Copyright © 2014 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

A general method for the purification of synthetic oligodeoxyribonucleotides containing strong secondary structure by reversed-phase high-performance liquid chromatography on PRP-1 resin.

PubMed

Germann, M W; Pon, R T; van de Sande, J H

1987-09-01

Synthetic 5'-dimethoxytritylated oligodeoxyribonucleotides, which contained strong secondary structure, were satisfactorily denatured and purified by reversed-phase HPLC on PRP-1 columns when strongly alkaline conditions (0.05 M NaOH) were employed. This procedure was suitable for the purification of hairpin structures, e.g., d(CG)nT4(CG)n (n = 4, 5, 6), and oligo(dG) sequences, e.g., d(G)24, as well as oligodeoxyribonucleotide probes which contained degenerate base sites. Oligodeoxyribonucleotides as long as 50 bases in length were purified. Recovery of injected oligonucleotides was typically 90% or better. The high capacity of the PRP-1 resin also allowed purification to be performed on a preparative scale (2-8 mg per injection). Enzymatic degradation and HPLC analysis indicated that no modification of the heterocyclic bases occurred under the alkaline conditions described.

One-dimensional mercury(II) halide coordination polymers of 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine ligand: Synthesis, crystal structure, spectroscopic and DFT studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saghatforoush, Lotfali, E-mail: saghatforoush@gmail.com; Khoshtarkib, Zeinab; Amani, Vahid

2016-01-15

Three new coordination polymers, [Hg(μ-bptz)X{sub 2}]{sub n} (X=Cl (1), Br (2)) and [Hg{sub 2}(μ-bptz)(μ-I){sub 2}I{sub 2}]{sub n} (3) (bptz=3,6-bis(2-pyridyl)-1,2,4,5-tetrazine) were synthesized. X-ray structural analysis indicated that compounds 1 and 2 are composed of one-dimensional (1D) linear chains while the compound 3 has 1D stair-stepped structure. The electronic band structure along with density of states (DOS) calculated by the DFT method indicates that compound 1 and 2 are direct band gap semiconductors; however, compound 3 is an indirect semiconductor. The linear optical properties of the compounds are also calculated by DFT method. According to the DFT calculations, the observed emission bandmore » of the compounds in solid state is due to electron transfer from an excited bptz-π* state (CBs) to the top of VBs. {sup 1}H NMR spectra of the compounds indicate that, in solution phase, the compounds don’t decompose completely. Thermal stability of the compounds is studied using TG, DTA methods. - Graphical abstract: Synthesis, crystal structure and emission spectra of [Hg(μ-bptz)X{sub 2}]{sub n} (X=Cl and Br) and [Hg{sub 2}(μ-bptz)(μ-I){sub 2}I{sub 2}]{sub n} are presented. The electronic band structure and linear optical properties of the compounds are calculated by the DFT method. - Highlights: • Three 1D Hg(II) halide coordination polymers with bptz ligand have been prepared. • The structures of the compounds are determined by single crystal XRD. • DFT calculations show that [Hg(μ-bptz)X{sub 2}]{sub n} (X=Cl and Br) have a direct band gap. • DFT calculations show that [Hg{sub 2}(μ-bptz)(μ-I){sub 2}I{sub 2}]{sub n} has an indirect band gap. • The compounds show an intraligand electron transfer emission band in solid state.« less

Dopaminergic receptor-ligand binding assays based on molecularly imprinted polymers on quartz crystal microbalance sensors.

PubMed

Naklua, Wanpen; Suedee, Roongnapa; Lieberzeit, Peter A

2016-07-15

Molecularly imprinted polymers (MIPs) have been successfully applied as selective materials for assessing the binding activity of agonist and antagonist of dopamine D1 receptor (D1R) by using quartz crystal microbalance (QCM). In this study, D1R derived from rat hypothalamus was used as a template and thus self-organized on stamps. Those were pressed into an oligomer film consisting of acrylic acid: N-vinylpyrrolidone: N,N'-(1,2-dihydroxyethylene) bis-acrylamide in a ratio of 2:3:12 spin coated onto a dual electrode QCM. Such we obtained one D1R-MIP-QCM electrode, whereas the other electrode carried the non-imprinted control polymer (NIP) that had remained untreated. Successful imprinting of D1R was confirmed by AFM. The polymer can re-incorporate D1R leading to frequency responses of 100-1200Hz in a concentration range of 5.9-47.2µM. In a further step such frequency changes proved inherently useful for examining the binding properties of test ligands to D1R. The resulting mass-sensitive measurements revealed Kd of dopamine∙HCl, haloperidol, and (+)-SCH23390 at 0.874, 25.6, and 0.004nM, respectively. These results correlate well with the values determined in radio ligand binding assays. Our experiments revealed that D1R-MIP sensors are useful for estimating the strength of ligand binding to the active single site. Therefore, we have developed a biomimetic surface imprinting strategy for QCM studies of D1R-ligand binding and presented a new method to ligand binding assay for D1R. Copyright © 2016 Elsevier B.V. All rights reserved.

Experimental demonstration of the possible role of Acanthamoeba polyphaga in the infection and disease progression in Buruli Ulcer (BU) using ICR mice

PubMed Central

Azumah, Bright K.; Addo, Phyllis G.; Dodoo, Alfred; Awandare, Gordon; Mosi, Lydia; Boakye, Daniel A.

2017-01-01

The transmission of Buruli ulcer (BU), caused by Mycobacterium ulcerans (MU), remains puzzling although a number of hypothesis including through bites of infected aquatic insects have been proposed. We report the results of experiments using ICR mice that give credence to our hypothesis that Acanthamoeba species may play a role in BU transmission. We cocultured MU N2 and MU 1615 which expresses red fluorescent protein (RFP) and Acanthamoeba polyphaga (AP), and confirmed infected AP by Ziehl-Neelsen (ZN) staining. We tested for viability of MU inside AP and observed strong RFP signals inside both trophozoites and cysts after 3 and 42 days of coculturing respectively. ICR mice were topically treated, either on shaved intact or shaved pinpricked rumps, with one of the following; MU N2 only (2.25 x 106 colony forming units [CFU] / ml), MU N2:AP coculture (2.96 x 104 CFU: 1.6 x 106 cells/ml), AP only (1.6 x 106 cells/ml), PYG medium and sterile distilled water. Both MU N2 only and MU N2:AP elicited reddening on day (D) 31; edema on D 45 and D 44 respectively, and ulcers on D 49 at pinpricked sites only. To ascertain infectivity and pathogenicity of MU N2 only and MU N2:AP, and compare their virulence, the standard mouse footpad inoculation method was used. MU N2:AP elicited reddening in footpads by D 3 compared to D 14 with MU N2 only of the same dose of MU N2 (2.96 x 104 CFU). ZN-stained MU were observed in both thin sectioned and homogenized lesions, and aspirates from infected sites. Viable MU N2 were recovered from cultures of the homogenates and aspirates. This study demonstrates in ICR mice MU transmission via passive infection, and shows that punctures in the skin are prerequisite for infection, and that coculturing of MU with AP enhances pathogenesis. PMID:28329001

Neutron-capture cross-section measurements of 74Ge and 76Ge in the energy region 0.4-14.8 MeV for neutrinoless double β decay applications

NASA Astrophysics Data System (ADS)

Bhike, Megha; Tornow, Werner

2013-10-01

Fast neutron capture cross sections for the reactions 74Ge(n, γ)75Ge and 76Ge(n, γ)77Ge have been measured in the neutron energy region 0.4-14.8 MeV with the activation method. The results are important to identify backgrounds in the neutrinoless double- β decay experiments GERDA and MAJORANA, which use germanium as both source and detector. Isotopically enriched targets which consisted of 86% of 76Ge and 14% of 74Ge were irradiated with mono-energetic neutrons produced via 3H(p,n)3He, 2H(d,n)3He and 3H(d,n)4He reactions. The cross sections were determined relative to 197Au(n, γ)198Au, 115In(n,n')115mIn and 197Au(n,2n)196Au standard cross sections. The activities of the products were measured using high-resolution γ-ray spctroscopy. The present results are compared with the evaluated data from ENDF/B-VII.1 and TALYS.

3D Structure of Tillage Soils

NASA Astrophysics Data System (ADS)

González-Torre, Iván; Losada, Juan Carlos; Falconer, Ruth; Hapca, Simona; Tarquis, Ana M.

2015-04-01

Soil structure may be defined as the spatial arrangement of soil particles, aggregates and pores. The geometry of each one of these elements, as well as their spatial arrangement, has a great influence on the transport of fluids and solutes through the soil. Fractal/Multifractal methods have been increasingly applied to quantify soil structure thanks to the advances in computer technology (Tarquis et al., 2003). There is no doubt that computed tomography (CT) has provided an alternative for observing intact soil structure. These CT techniques reduce the physical impact to sampling, providing three-dimensional (3D) information and allowing rapid scanning to study sample dynamics in near real-time (Houston et al., 2013a). However, several authors have dedicated attention to the appropriate pore-solid CT threshold (Elliot and Heck, 2007; Houston et al., 2013b) and the better method to estimate the multifractal parameters (Grau et al., 2006; Tarquis et al., 2009). The aim of the present study is to evaluate the effect of the algorithm applied in the multifractal method (box counting and box gliding) and the cube size on the calculation of generalized fractal dimensions (Dq) in grey images without applying any threshold. To this end, soil samples were extracted from different areas plowed with three tools (moldboard, chissel and plow). Soil samples for each of the tillage treatment were packed into polypropylene cylinders of 8 cm diameter and 10 cm high. These were imaged using an mSIMCT at 155keV and 25 mA. An aluminium filter (0.25 mm) was applied to reduce beam hardening and later several corrections where applied during reconstruction. References Elliot, T.R. and Heck, R.J. 2007. A comparison of 2D and 3D thresholding of CT imagery. Can. J. Soil Sci., 87(4), 405-412. Grau, J, Médez, V.; Tarquis, A.M., Saa, A. and Díaz, M.C.. 2006. Comparison of gliding box and box-counting methods in soil image analysis. Geoderma, 134, 349-359. González-Torres, Iván. Theory and application of multifractal analysis methods in images for the study of soil structure. Master thesis, UPM, 2014. Houston, A.N.; S. Schmidt, A.M. Tarquis, W. Otten, P.C. Baveye, S.M. Hapca. Effect of scanning and image reconstruction settings in X-ray computed tomography on soil image quality and segmentation performance. Geoderma, 207-208, 154-165, 2013a. Houston, A, Otten, W., Baveye, Ph., Hapca, S. Adaptive-Window Indicator Kriging: A Thresholding Method for Computed Tomography, Computers & Geosciences, 54, 239-248, 2013b. Tarquis, A.M., R.J. Heck, D. Andina, A. Alvarez and J.M. Antón. Multifractal analysis and thresholding of 3D soil images. Ecological Complexity, 6, 230-239, 2009. Tarquis, A.M.; D. Giménez, A. Saa, M.C. Díaz. and J.M. Gascó. Scaling and Multiscaling of Soil Pore Systems Determined by Image Analysis. Scaling Methods in Soil Systems. Pachepsky, Radcliffe and Selim Eds., 19-33, 2003. CRC Press, Boca Ratón, Florida. Acknowledgements First author acknowledges the financial support obtained from Soil Imaging Laboratory (University of Gueplh, Canada) in 2014.

Design and fabrication of N x N optical couplers based on organic polymer optical waveguides

NASA Astrophysics Data System (ADS)

Krchnavek, Robert R.; Rode, Daniel L.

1994-08-01

In this report, we examine the design and fabrication of a planar, 10x10 optical coupler utilizing photopolymerizable organic polymers. Background information on the theory of operation of the coupler culminating in a set of design equations is presented. The details of the material processing are described, including the preparation of monomer mixtures that result in single-mode polymer waveguides (lambda = 1300 nm) that have core dimensions approximately equal to those of single-mode fiber. This is necessary to insure high coupling efficiency between the planar device and optical fiber. A unique method of aligning and attaching optical fibers to the coupler is demonstrated. This method relies on patterned alignment ways, a transcision cut, and single-mode D-fiber. A theoretical analysis of the in situ monitoring technique used to fabricate the single-mode D-fiber is presented and compared favorably with the experimental results. Finally, the 10x10 coupler is characterized. We have measured an excess loss of approximately 8 dB.

(K, Na, Li)(Nb, Ta)O3:Mn lead-free single crystal with high piezoelectric properties

PubMed Central

Huo, Xiaoqing; Zhang, Rui; Zheng, Limei; Zhang, Shujun; Wang, Rui; Wang, Junjun; Sang, Shijing; Yang, Bin; Cao, Wenwu

2016-01-01

Lead-free single crystal, (K, Na, Li)(Nb, Ta)O3:Mn, was successfully grown using top-seeded solution growth method. Complete matrix of dielectric, piezoelectric and elastic constants for [001]C poled single crystal was determined. The piezoelectric coefficient d33 measured by the resonance method was 545 pC/N, which is almost three times that of its ceramic counterpart. The values measured by the Berlincourt meter ( d33∗=630pC/N) and strain-field curve ( d33∗∗=870pm/V) were even higher. The differences were assumed to relate with the different extrinsic contributions of domain wall vibration and domain wall translation during the measurements by different approaches, where the intrinsic contribution (on the order of 539 pm/V) was supposed to be the same. The crystal has ultrahigh electromechanical coupling factor (k33 ~ 95%) and high ultrasound velocity, which make it promising for high frequency medical transducer applications. PMID:27594704

Customized design and 3D printing of face seal for an N95 filtering facepiece respirator.

PubMed

Cai, Mang; Li, Hui; Shen, Shengnan; Wang, Yu; Yang, Quan

2018-03-01

Filtering Facepiece Respirator (FFR) is the most common respirator users in the health care environment utilize for personal protection from outside particles. Comfort and fit are important while wearing an FFR. This paper proposes a novel technology to produce customized face seal design for improving the wearing comfort and fit of FFR wearers. In order to customize the design of face seals, we scanned the faces of three subjects using three-dimensional (3D) laser scanning method. A customized face seal for a 3M 8210 N95 FFR for each headform was designed using reverse engineering technique. Next, the face seal prototypes were fabricated with Acrylonitrile Butadiene Styrene (ABS) plastic using the 3D printing method. A force sensing system based on Arduino Uno R3 was developed, and the force sensor of this system was inserted between the FFR and headform to measure contact pressure. Experimental results showed that the newly designed FFR face seal provided the subjects with an improved contact pressure.

A validated solid-liquid extraction method for the HPLC determination of polyphenols in apple tissues Comparison with pressurised liquid extraction.

PubMed

Alonso-Salces, Rosa M; Barranco, Alejandro; Corta, Edurne; Berrueta, Luis A; Gallo, Blanca; Vicente, Francisca

2005-02-15

A solid-liquid extraction procedure followed by reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with a photodiode array detector (DAD) for the determination of polyphenols in freeze-dried apple peel and pulp is reported. The extraction step consists in sonicating 0.5g of freeze-dried apple tissue with 30mL of methanol-water-acetic acid (30:69:1, v/v/v) containing 2g of ascorbic acid/L, for 10min in an ultrasonic bath. The whole method was validated, concluding that it is a robust method that presents high extraction efficiencies (peel: >91%, pulp: >95%) and appropriate precisions (within day: R.S.D. (n = 5) <5%, and between days: R.S.D. (n = 5) <7%) at the different concentration levels of polyphenols that can be found in apple samples. The method was compared with one previously published, consisting in a pressurized liquid extraction (PLE) followed by RP-HPLC-DAD determination. The advantages and disadvantages of both methods are discussed.

Temperature profiles of different cooling methods in porcine pancreas procurement.

PubMed

Weegman, Bradley P; Suszynski, Thomas M; Scott, William E; Ferrer Fábrega, Joana; Avgoustiniatos, Efstathios S; Anazawa, Takayuki; O'Brien, Timothy D; Rizzari, Michael D; Karatzas, Theodore; Jie, Tun; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K

2014-01-01

Porcine islet xenotransplantation is a promising alternative to human islet allotransplantation. Porcine pancreas cooling needs to be optimized to reduce the warm ischemia time (WIT) following donation after cardiac death, which is associated with poorer islet isolation outcomes. This study examines the effect of four different cooling Methods on core porcine pancreas temperature (n = 24) and histopathology (n = 16). All Methods involved surface cooling with crushed ice and chilled irrigation. Method A, which is the standard for porcine pancreas procurement, used only surface cooling. Method B involved an intravascular flush with cold solution through the pancreas arterial system. Method C involved an intraductal infusion with cold solution through the major pancreatic duct, and Method D combined all three cooling Methods. Surface cooling alone (Method A) gradually decreased core pancreas temperature to <10 °C after 30 min. Using an intravascular flush (Method B) improved cooling during the entire duration of procurement, but incorporating an intraductal infusion (Method C) rapidly reduced core temperature 15-20 °C within the first 2 min of cooling. Combining all methods (Method D) was the most effective at rapidly reducing temperature and providing sustained cooling throughout the duration of procurement, although the recorded WIT was not different between Methods (P = 0.36). Histological scores were different between the cooling Methods (P = 0.02) and the worst with Method A. There were differences in histological scores between Methods A and C (P = 0.02) and Methods A and D (P = 0.02), but not between Methods C and D (P = 0.95), which may highlight the importance of early cooling using an intraductal infusion. In conclusion, surface cooling alone cannot rapidly cool large (porcine or human) pancreata. Additional cooling with an intravascular flush and intraductal infusion results in improved core porcine pancreas temperature profiles during procurement and histopathology scores. These data may also have implications on human pancreas procurement as use of an intraductal infusion is not common practice. © 2014 John Wiley & Sons A/S Published by John Wiley & Sons Ltd.

NASA TEERM Hexavalent Chrome Alternatives Projects

DTIC Science & Technology

2011-08-18

1 N2-2 N3-2 N4-2 N5-2 N6-2 N7-2 N8-2 N9-2 N10-2 N11-2 N12-2 N13-2 H H2-1 H3-1 H4-1 H5-1 H6-1 H7-1 H8-1 H9-1 H10-1 H11-1 H12-1 H13 -1 H2-2 H3-2 H4-2...H5-2 H6-2 H7-2 H8-2 H9-2 H10-2 H11-2 H12-2 H13 -2 D D2-1 D3-1 D4-1 D5-1 D6-1 D7-1 D8-1 D9-1 D10-1 D11-1 D12-1 D13-1 D2-2 D3-2 D4-2 D5-2 D6-2 D7-2...Color, Adhesion, Impact , Flexibility, Fluid Resistance, Filiform Corrosion, Salt-Spray Corrosion, Artificial Weathering, Stripability, Restoration

Effect of solar radio bursts on GNSS signal reception over Europe for the period 1999-2013

NASA Astrophysics Data System (ADS)

Chevalier, Jean-Marie; Bergeot, Nicolas; Marqué, Christophe; Aerts, Wim; Bruyninx, Carine

2015-04-01

Intense solar radio bursts (SRB) emitted at L-band frequencies can affect the carrier-to-noise C/N0 ratio of Global Navigation Satellite Systems (GNSS) signals by increasing the background noise. Such space weather events can consequently decrease the quality of GNSS-based results especially for kinematic high-precision positioning. It is thus important to develop a method capable to detect such events in near real time on a wide area. For this purpose, the ROB-IONO software was adapted for analysing the effect of SRB on the dense EUREF Permanent GNSS Network (EPN). First, S1 and S2 raw data extracted from RINEX files were converted into the C/N0 unit (dB.Hz) taking into account manufacturer corrections. Then, the differences (ΔC/N0) between all these C/N0observables and their medians of the 7 previous satellite ground track repeat cycles, i.e. their normal quiet state, were computed. The mean of all these well-calibrated ΔC/N0values from different GNSS receivers and satellites offer at each epoch a reliable metric to detect and quantify the impact of a SRB. We investigated the degradation of GPS and GLONASS C/N0 on the entire EPN during 10 intense SRBs occurring at daylight over Europe between 1999 and 2013. The analysis shows that: (1) GPS and GLONASS ΔC/N0 agree at the 0.1±0.2dB.Hz level; (2) The standard deviation of the mean ΔC/N0of the EPN GNSS receivers is below 1dB.Hz 96% of the time, and below 0.6dB.Hz 76% of the time; (3) maximum ΔC/N0 degradation occurs at the epoch of maximum solar peak flux delivered by the solar ground observatories; (4) C/N0 degradation becomes larger with increasing solar zenithal angle. Consequently, the ROB-IONO software is capable to detect the degradation of GNSS signal reception over Europe due to SRBs. In addition, by taking advantage of the increasing number of EPN stations delivering C/N0 data since 2005, even less intense SRB events can now be detected. Finally, the developed method can be completely applied in near real time.

Low Temperature Pulsed Plasma Deposition. Part 1. A New Technique for Thin Film Deposition with Complete Gas Dissociation.

DTIC Science & Technology

1988-04-12

Res. Minneapolis Dr P Klocek Texas Instruments, Dallas Dr D N Lewis Naval Research Lab Dr S Musikant General Electric Co, Philadelphia Dr D Perry US...by utilising only a small fraction of the available reactants. Not only is this wasteful, limiting the method to reactants that are comparatively

Optimal design of a combustion chamber of gas turbine engine by a Combustion chamber 1D-2D computer program

NASA Astrophysics Data System (ADS)

Aleksandrov, Y. B.; Mingazov, B. G.

2017-09-01

The paper shows a method of modeling and optimization of processes in combustion chambers of gas turbine engines using a computer program developed by a team at the Department of Jet Engines and Power Plants (DJEPP) of Technical University named after A N Tupolev KNRTU-KAI.

A Perception Test of Infrared Images of Soldiers in Camouflaged Uniforms

DTIC Science & Technology

1998-03-09

psychology ," Science, pp. 990- 1000, 1973. 3.) Macmillan, N.A., and Creelman , C.D.,I991, Detection Theory: A User’s Guide, Cambridge University Press. 4...levels, using the rating scale method shown in McMillan and Creelman ( 1996). The estimated true d was calculated as the mean of the liberal and

3D morphometry using automated aortic segmentation in native MR angiography: an alternative to contrast enhanced MRA?

PubMed Central

Müller-Eschner, Matthias; Müller, Tobias; Biesdorf, Andreas; Wörz, Stefan; Rengier, Fabian; Böckler, Dittmar; Kauczor, Hans-Ulrich; Rohr, Karl

2014-01-01

Introduction Native-MR angiography (N-MRA) is considered an imaging alternative to contrast enhanced MR angiography (CE-MRA) for patients with renal insufficiency. Lower intraluminal contrast in N-MRA often leads to failure of the segmentation process in commercial algorithms. This study introduces an in-house 3D model-based segmentation approach used to compare both sequences by automatic 3D lumen segmentation, allowing for evaluation of differences of aortic lumen diameters as well as differences in length comparing both acquisition techniques at every possible location. Methods and materials Sixteen healthy volunteers underwent 1.5-T-MR Angiography (MRA). For each volunteer, two different MR sequences were performed, CE-MRA: gradient echo Turbo FLASH sequence and N-MRA: respiratory-and-cardiac-gated, T2-weighted 3D SSFP. Datasets were segmented using a 3D model-based ellipse-fitting approach with a single seed point placed manually above the celiac trunk. The segmented volumes were manually cropped from left subclavian artery to celiac trunk to avoid error due to side branches. Diameters, volumes and centerline length were computed for intraindividual comparison. For statistical analysis the Wilcoxon-Signed-Ranked-Test was used. Results Average centerline length obtained based on N-MRA was 239.0±23.4 mm compared to 238.6±23.5 mm for CE-MRA without significant difference (P=0.877). Average maximum diameter obtained based on N-MRA was 25.7±3.3 mm compared to 24.1±3.2 mm for CE-MRA (P<0.001). In agreement with the difference in diameters, volumes obtained based on N-MRA (100.1±35.4 cm3) were consistently and significantly larger compared to CE-MRA (89.2±30.0 cm3) (P<0.001). Conclusions 3D morphometry shows highly similar centerline lengths for N-MRA and CE-MRA, but systematically higher diameters and volumes for N-MRA. PMID:24834406

Target-strength Measurements of Sandfish Arctoscopus japonicus

NASA Astrophysics Data System (ADS)

Yoon, Eun-A.; Lee, Kyounghoon; Oh, Wooseok; Choi, Junghwa; Hwang, Kangseok; Kang, Myounghee

2018-03-01

The goal of this study was to estimate the target strength (TS) of the sandfish Arctoscopus japonicus using in-situ and ex-situ methods with an echosounder. For the in-situ TS measurement, the survey was conducted by taking hydroacoustic measurements at 38 and 120 kHz and using a coastal gill net, in Goseong, in the northeastern sea of Korea in early December 2009. Ex-situ measurement of TS used live specimens and the tethering method, and was conducted at 120 kHz. The distribution of fork length (FL) was bimodal: 14.6-19.8 cm (n = 241 individuals, mean = 17.0 cm) for males and 16.3-24.5 cm (n = 105 individuals, mean = 19.6 cm) for females. The in-situ TS ranged from -79.8 to -59.1 dB (mean = -74.3 dB for males and -64.1 dB for females) at 38 kHz and -79.9 to -56.2 dB (mean = -74.3 dB for males and -64.1 dB for females) at 120 kHz. The mean TS of females was approximately 10 dB higher than that of males at each dominant frequency. The female ex-situ TS values ranged from 68.5 to -54.6 dB, and those of males was from -67.7 to -59.3 dB. The mean TS value for females was 2.9 dB higher than that of males. These results may be used in echo-integration surveys of sandfish to estimate their abundance and seasonal distribution.

Interferon induction by two 2'-modified double-helical RNAs, poly(2'-fluoro-2'-deoxyinosinic acid) x poly(cytidylic acid) and poly(2'-chloro-2'-deoxyinosinic acid) x poly(cytidylic acid).

PubMed

De Clercq, E; Stollar, B D; Hobbs, J; Fukui, T; Kakiuchi, N; Ikehara, M

1980-01-01

In addition to the 2'-azido analogue of (I)n x (C)n, (dIn3)n x (C)n, we have found two other (I)n x (C)n analogues, (dIfl)n x (C)n and (dIcl)n x (C)n, in which the 2'-hydroxyls of the (I)n strand are replaced by either fluorine or chlorine, to be highly effective in inducing interferon. This contrasted with the lack of interferon-inducing activity noted for various other 2'-halogeno analogues of (I)n x (C)n and (A)n x (U)n, i.e. (I)n x (dCcl)n, (dAfl)n x (U)n, (dAcl)n x (U)n, (A)n x (dUfl)n and (A)n x (dUcl)n. In most assay systems, viz. primary rabbit kidney cells, human diploid fibroblasts, HeLa cells, interferon-primed mouse L-929 cells, and intact rabbits, (dIfl)n x (C)n and (dIcl)n x (C)n induced interferon levels that were comparable to those induced by (I)n x (C)n. There was one particular system (L-929 cells treated with DEAE-dextran), however, in which (dIfl)n x (C)n and (dIcl)n x (C)n, unlike (I)n x (C)n, failed to stimulate interferon production. As monitored by both radiochemical and biological means, (dIfl)n x (C)n and, to a lesser extent, (dIcl)n x (C)n were more resistant to degradation by ribonuclease A, T1 and human serum nucleases than was (I)n x (C)n. In their reactivity towards antibodies to double-stranded RNA (dIfl)n x (C)n and (dIcl)n x (C)n conformed more closely to (I)n x (C)n than did other 2'-substituted (e.g. 2'-O-methyl or 2'-O-ethyl) analogues of (I)n x (C)n. The high interferon-inducing potency of (dIfl)n x (C)n and (dIcl)n x (C)n has both theoretical and practical implications. While our findings suggest that (dIfl)n x (C)n and (dIcl)n x (C)n should be further explored for their therapeutic potentials, they also strengthen the notion that the interferon-inducing capacity, and possibly other biological functions of double-stranded RNAs is dependent on the recognition of the overall conformation of the polynucleotide rather than on the binding of specific functional groups such as the 2'-hydroxyl group.

Intermolecular interactions in the solid state structures of neutral and N-protonated 5-alkoxymethyl-8-hydroxyquinolines

NASA Astrophysics Data System (ADS)

Schulze, Mathias M.; Böhme, Uwe; Schwarzer, Anke; Weber, Edwin

2017-04-01

A series of five different alkoxymethyl substituted derivatives of 8-hydroxyquinoline was synthesised both in protonated (1a-1e) and neutral (2a-2e) form. The alkoxymethyl groups are MeO (1a, 2a), EtO (1b, 2b), n-PrO (1c, 2c), iso-PrO (1d, 2d), n-BuO (1e, 2e). The compounds were characterised by single crystal X-ray diffraction and spectroscopic methods. Hirshfeld surface analysis was performed to analyse the crystal packing quantitatively. Topological analysis of the electron density distribution delivers information about the strength of the hydrogen bonds. The overall results reveal a main difference between the charged (1a-1d) and uncharged (2a-2e) compounds in the orientation of the hydroxyl group resulting in a different cyclic dimer formation. In both cases the structures are dominated by hydrogen bonding (1a-1d: Osbnd H⋯Cl, Nsbnd H⋯Cl and 2a-2e: Osbnd H⋯N). Furthermore, all crystal structures show π involved interactions though taking only a minor part in the packing of the molecules.

Studies on synthesis and anticancer activity of selected N-(2-fluoroethyl)-N-nitrosoureas.

PubMed

Johnston, T P; Kussner, C L; Carter, R L; Frye, J L; Lomax, N R; Plowman, J; Narayanan, V L

1984-11-01

An activated carbamate, 2-nitrophenyl (2-fluoroethyl)nitrosocarbamate (3), was used to advantage in the synthesis of the water-soluble (2-fluoroethyl)nitrosoureas 6a--d from 2-aminoethanol, (1 alpha, 2 beta, 3 alpha)-2-amino-1,3-cyclohexanediol, cis-2-hydroxycyclohexanol, and 2-amino-2-deoxy-D-glucose. In a variation of this method, 2,4,5-trichlorophenyl (2-fluoroethyl)carbamate (4) was used to prepare the urea from which the essentially water-insoluble N-(2,6-dioxo-3-piperidinyl)-N-(2-fluoroethyl)-N-nitrosourea (6e) was derived. The anticancer activity of these nitrosoureas was determined against the murine tumors B16 melanoma and Lewis lung carcinoma and found to be significant and comparable to their chloroethyl counterparts. On the basis of results from both systems, the dihydroxycyclohexyl derivative 6b may be the most effective.

First Measurement of the Radionuclide Purity of the Therapeutic Isotope 67Cu Produced by 68Zn(n,x) Reaction Using natC(d,n) Neutrons

NASA Astrophysics Data System (ADS)

Sato, Nozomi; Tsukada, Kazuaki; Watanabe, Satoshi; Ishioka, Noriko S.; Kawabata, Masako; Saeki, Hideya; Nagai, Yasuki; Kin, Tadahiro; Minato, Futoshi; Iwamoto, Nobuyuki; Iwamoto, Osamu

2014-07-01

We have for the first time studied the radionuclide purity of the therapeutic isotope 67Cu produced by the 68Zn(n,x)67Cu reaction. The neutrons were obtained by the natC(d,n) reaction using 40 MeV deuterons. We measured the γ-ray spectra of the reaction products produced by bombarding an enriched 68ZnO sample with the neutrons with a high-purity Ge detector. We found that the relative production yields of the impurity radionuclides 64Cu, 65Zn, and 69mZn to 67Cu are extremely low. The result indicates that the 68Zn(n,x)67Cu reaction is the most promising among those proposed routes until now for producing high-quality 67Cu, and could solve a longstanding problem of establishing an appropriate production method for 67Cu.

2D Electrides as Promising Anode Materials for Na-Ion Batteries from First-Principles Study.

PubMed

Hu, Junping; Xu, Bo; Yang, Shengyuan A; Guan, Shan; Ouyang, Chuying; Yao, Yugui

2015-11-04

Searching for suitable anodes with good performance is a key challenge for rechargeable Na-ion batteries (NIBs). Using the first-principles method, we predict that 2D nitrogen electride materials can be served as anode materials for NIBs. Particularly, we show that Ca2N meets almost all the requirements of a good NIB anode. Each formula unit of a monolayer Ca2N sheet can absorb up to four Na atoms, corresponding to a theoretical specific capacity of 1138 mAh·g(-1). The metallic character for both pristine Ca2N and its Na intercalated state NaxCa2N ensures good electronic conduction. Na diffusion along the 2D monolayer plane can be very fast even at room temperature, with a Na migration energy barrier as small as 0.084 eV. These properties are key to the excellent rate performance of an anode material. The average open-circuit voltage is calculated to be 0.18 V vs Na/Na(+) for the chemical stoichiometry of Na2Ca2N and 0.09 V for Na4Ca2N. The relatively low average open-circuit voltage is beneficial to the overall voltage of the cell. In addition, the 2D monolayers have very small lattice change upon Na intercalation, which ensures a good cycling stability. All these results demonstrate that the Ca2N monolayer could be an excellent anode material for NIBs.

Prevalence and antibiotic resistance of Pseudomonas aeruginosa in water samples in central Italy and molecular characterization of oprD in imipenem resistant isolates.

PubMed

Schiavano, Giuditta Fiorella; Carloni, Elisa; Andreoni, Francesca; Magi, Silvia; Chironna, Maria; Brandi, Giorgio; Amagliani, Giulia

2017-01-01

This study aimed to analyse the prevalence, antibiotic resistance and genetic relatedness of P. aeruginosa isolates obtained from potable and recreational water samples (n. 8,351) collected from different settings (swimming pools, n. 207; healthcare facilities, n 1,684; accommodation facilities, n. 1,518; municipal waterworks, n. 4,500; residential buildings, n. 235). Possible mechanisms underlying resistance to imipenem, with particular focus on those involving oprD-based uptake, were also explored. Isolation and identification of Pseudomonas aeruginosa was performed according to the standardized procedure UNI EN ISO 16266:2008 followed by PCR confirmation. Antibiotic Susceptibility testing was conducted according to EUCAST standardized disk diffusion method. Genetic relatedness of strains was carried out by RAPD. The sequence of the oprD gene was analyzed by standard method. Fifty-three samples (0.63%) were positive for P. aeruginosa, of which 10/207 (4.83%) were from swimming pools. Five isolates (9.43%) were resistant to imipenem, one to Ticarcillin + Clavulanate, one to both Piperacillin and Ticarcillin + Clavulanate. The highest isolation rate of imipenem resistant P. aeruginosa was observed in swimming pool water. Identical RAPD profiles were found in isolates from the same location in the same year or even in different years. Imipenem resistant strains were identified as carbapenemase-negative and resistance has been associated with inactivating mutations within the oprD gene, with a concomitant loss of porin. RAPD results proved that a water system can remain colonized by one strain for long periods and the contamination may be difficult to eradicate. This study has revealed the presence of P. aeruginosa in different water samples, including resistant strains, especially in swimming pools, and confirmed the role of porins as a contributing factor in carbapenem resistance in Gram-negative bacteria.

Assessment of liver fibrosis with 2-D shear wave elastography in comparison to transient elastography and acoustic radiation force impulse imaging in patients with chronic liver disease.

PubMed

Gerber, Ludmila; Kasper, Daniela; Fitting, Daniel; Knop, Viola; Vermehren, Annika; Sprinzl, Kathrin; Hansmann, Martin L; Herrmann, Eva; Bojunga, Joerg; Albert, Joerg; Sarrazin, Christoph; Zeuzem, Stefan; Friedrich-Rust, Mireen

2015-09-01

Two-dimensional shear wave elastography (2-D SWE) is an ultrasound-based elastography method integrated into a conventional ultrasound machine. It can evaluate larger regions of interest and, therefore, might be better at determining the overall fibrosis distribution. The aim of this prospective study was to compare 2-D SWE with the two best evaluated liver elastography methods, transient elastography and acoustic radiation force impulse (point SWE using acoustic radiation force impulse) imaging, in the same population group. The study included 132 patients with chronic hepatopathies, in which liver stiffness was evaluated using transient elastography, acoustic radiation force impulse imaging and 2-D SWE. The reference methods were liver biopsy for the assessment of liver fibrosis (n = 101) and magnetic resonance imaging/computed tomography for the diagnosis of liver cirrhosis (n = 31). No significant difference in diagnostic accuracy, assessed as the area under the receiver operating characteristic curve (AUROC), was found between the three elastography methods (2-D SWE, transient elastography, acoustic radiation force impulse imaging) for the diagnosis of significant and advanced fibrosis and liver cirrhosis in the "per protocol" (AUROCs for fibrosis stages ≥2: 0.90, 0.95 and 0.91; for fibrosis stage [F] ≥3: 0.93, 0.95 and 0.94; for F = 4: 0.92, 0.96 and 0.92) and "intention to diagnose" cohort (AUROCs for F ≥2: 0.87, 0.92 and 0.91; for F ≥3: 0.91, 0.93 and 0.94; for F = 4: 0.88, 0.90 and 0.89). Therefore, 2-D SWE, ARFI imaging and transient elastography seem to be comparably good methods for non-invasive assessment of liver fibrosis. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Resistant mechanism against nelfinavir of subtype C human immunodeficiency virus type 1 proteases

NASA Astrophysics Data System (ADS)

Liu, Xiaoqing; Dai, Qi; Li, Lihua; Xiu, Zhilong

2011-02-01

Human immunodeficiency virus type 1 protease (HIV-1 PR) is one of the major targets of anti-AIDS drug discovery, and the subtype C HIV-1 is infecting more and more humans. In this work, we executed computational simulations of subtype B (labeled B(WT)) HIV-1 PR, D30N mutant B (labeled B(D30N)) HIV-1 PR, subtype C (labeled C(Ref)) HIV-1 PR, D30N mutant C (labeled C(D30N)) HIV-1 PR, and D30N/N83T mutant C (labeled C(D30N/N83T)) HIV-1 PR with drug nelfinavir (NFV), aiming at clarifying (1) the resistant mechanism against NFV due to D30N mutation in subtype C HIV-1 PR; (2) the reason that the emergence rate of N83T mutation in C(D30N) HIV-1 PR is higher than that in B(D30N) HIV-1 PR; (3) the affinity of NFV with C(D30N/N83T) HIV-1 PR is higher than B(D30N) and C(D30N) HIV-1 PRs. The results indicate: (1) D30N mutation in subtype C HIV-1 PR reduces the hydrogen bond between the 30th residue and NFV, and the binding free energy contributions of some residues decrease; (2) the hydrogen bonds between the 83th/83'th residue and the 34th/34'th residue exist in both B(D30N) and C(D30N/N83T) HIV-1 PRs, while they disappear in C(D30N) HIV-1 PR. Meanwhile, the binding free energy contribution of N30 in C(D30N) is lower than that in B(D30N) and C(D30N/N83T); (3) N83T mutation makes some residues dislocate, and the contributions of these residues to binding free energy in C(D30N/N83T) increase comparing to those in B(D30N) and C(D30N). Our findings suggest that despite the nonactive site mutations, the polymorphisms regulate the emergence rates of these drug-resistant mutants.

The Effects of Simultaneous Dual Focus Lenses on Refractive Development in Infant Monkeys

PubMed Central

Arumugam, Baskar; Hung, Li-Fang; To, Chi-ho; Holden, Brien; Smith, Earl L.

2014-01-01

Purpose. We investigated the effects of two simultaneously imposed, competing focal planes on refractive development in monkeys. Methods. Starting at 3 weeks of age and continuing until 150 ± 4 days of age, rhesus monkeys were reared with binocular dual-focus spectacle lenses. The treatment lenses had central 2-mm zones of zero power and concentric annular zones with alternating powers of +3.0 diopter [D] and plano (pL or 0 D) (n = 7; +3D/pL) or −3.0 D and plano (n = 7; −3D/pL). Retinoscopy, keratometry, and A-scan ultrasonography were performed every 2 weeks throughout the treatment period. For comparison purposes data were obtained from monkeys reared with full field (FF) +3.0 (n = 4) or −3.0 D (n = 5) lenses over both eyes and 33 control animals reared with unrestricted vision. Results. The +3 D/pL lenses slowed eye growth resulting in hyperopic refractive errors that were similar to those produced by FF+3 D lenses (+3 D/pL = +5.25 D, FF +3 D = +4.63 D; P = 0.32), but significantly more hyperopic than those observed in control monkeys (+2.50 D, P = 0.0001). One −3 D/pL monkey developed compensating axial myopia; however, in the other −3 D/pL monkeys refractive development was dominated by the zero-powered portions of the treatment lenses. The refractive errors for the −3 D/pL monkeys were more hyperopic than those in the FF −3 D monkeys (−3 D/pL = +3.13 D, FF −3D = −1.69 D; P = 0.01), but similar to those in control animals (P = 0.15). Conclusions. In the monkeys treated with dual-focus lenses, refractive development was dominated by the more anterior (i.e., relatively myopic) image plane. The results indicate that imposing relative myopic defocus over a large proportion of the retina is an effective means for slowing ocular growth. PMID:25324283

Progressively Communicating Rich Telemetry from Autonomous Underwater Vehicles via Relays

DTIC Science & Technology

2012-06-01

wireless sensor networks using an autonomous underwater vehicle. In Robotics and...communication over multiple kilometers. In addition to wireless com- munication methods , the recently developed Nereus[12] vehicle at WHOI spools out...A P T U R E M e ss a g e s P ro ce ss / T h re a d M a n a g e m e n t C o n fi g u ra ti o n P a rs in g Network Manager Frame Scheduling

Revision of the carnivorous snail genus Discartemon Pfeiffer, 1856, with description of twelve new species (Pulmonata, Streptaxidae)

PubMed Central

Siriboon, Thanit; Sutcharit, Chirasak; Naggs, Fred; Rowson, Ben; Panha, Somsak

2014-01-01

Abstract Twelve new species of the streptaxid snail genus Discartemon Pfeiffer, 1856 are described from southern Thailand and western Malaysia, D. afthonodontia sp. n., D. circulus sp. n., D. deprima sp. n., D. discadentus sp. n., D. discamaximus sp. n., D. expandus sp. n., D. flavacandida sp. n., D. kotanensis sp. n., and D. megalostraka sp. n. from southern Thailand, as well as D. conicus sp. n., D. epipedis sp. n. and D. triancus sp. n. from western Malaysia. All 15 previously described species are revised and commented upon based on examined material. Streptaxis paradiscus Möllendorff, 1900 is considered a junior subjective synonym of the type species D. discus (Pfeiffer, 1853). Details of the genital anatomy of twelve species, and the radula and pallial system, are provided for the first time. An identification key is provided. PMID:24843260

Core follow calculation with the nTRACER numerical reactor and verification using power reactor measurement data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, Y. S.; Joo, H. G.; Yoon, J. I.

The nTRACER direct whole core transport code employing the planar MOC solution based 3-D calculation method, the subgroup method for resonance treatment, the Krylov matrix exponential method for depletion, and a subchannel thermal/hydraulic calculation solver was developed for practical high-fidelity simulation of power reactors. Its accuracy and performance is verified by comparing with the measurement data obtained for three pressurized water reactor cores. It is demonstrated that accurate and detailed multi-physic simulation of power reactors is practically realizable without any prior calculations or adjustments. (authors)

Assessing Clinical Significance: Does it Matter which Method we Use?

ERIC Educational Resources Information Center

Atkins, David C.; Bedics, Jamie D.; Mcglinchey, Joseph B.; Beauchaine, Theodore P.

2005-01-01

Measures of clinical significance are frequently used to evaluate client change during therapy. Several alternatives to the original method devised by N. S. Jacobson, W. C. Follette, & D. Revenstorf (1984) have been proposed, each purporting to increase accuracy. However, researchers have had little systematic guidance in choosing among…

Potential of oregano essential oil and MAP to extend the shelf life of fresh swordfish: a comparative study with ice storage.

PubMed

Giatrakou, V; Kykkidou, S; Papavergou, A; Kontominas, M G; Savvaidis, I N

2008-05-01

The present study evaluated the effect of modified atmosphere packaging (MAP, 5% O(2)/50% CO(2)/45% N(2); treatment M), the addition of oregano oil (0.1%, v/w; treatment AO) as a natural preservative, as well as their combination (treatment MO) on the quality and shelf life extension of fresh Mediterranean swordfish fillets during a refrigerated storage (4 degrees C) period of 18 d. Simultaneously, swordfish fillets were stored under aerobic conditions (control treatment A, 4 degrees C) and on ice (usual commercial method of preservation, treatment I, 0 degrees C). Among the 5 treatments examined in the present study, the most effective one to inhibit the microbial and sensory spoilage proved to be the MO treatment, achieving a shelf life extension of 8 to 9 d. The dominant bacteria in the microflora of swordfish, irrespective of treatment, were the Pseudomonads and the H(2)S-producing bacteria, while both lactic acid bacteria (LAB) and the Enterobacteriaceae produced the lowest populations in swordfish samples kept on ice. Among the chemical indices examined, thiobarbituric acid (TBA) values showed no specific trend of lipid oxidation for swordfish, irrespective of treatment. Final trimethylamine nitrogen (TMA-N) and total volatile basic nitrogen (TVB-N) values for treatments, A, AO, M, and MO ranged between 1.33 and 14.29 mg N/100 g and 14.11 to 55.52 mg N/100 g, respectively, whereas for I samples they remained almost unchanged during storage. Sensory analysis (taste attribute) correlated well with microbiological analysis, indicating a shelf life of approximately 5 to 6 d for control, 10 to 11 d for AO, 12 d for I, 13 d for M, and 14 d for MO samples.

The effects of music intervention in the management of chronic pain: a single-blind, randomized, controlled trial.

PubMed

Guétin, Stéphane; Giniès, Patrick; Siou, Didier Kong A; Picot, Marie-Christine; Pommié, Christelle; Guldner, Elisabeth; Gosp, Anne-Marie; Ostyn, Katelyne; Coudeyre, Emmanuel; Touchon, Jacques

2012-05-01

A music intervention method in the management of pain was recently developed while taking account of recommendations in the scientific literature. The objective of this study was to assess the usefulness of this music intervention to the management of patients with chronic pain. A controlled, single-blind, randomized trial was used. Eighty-seven patients presenting with lumbar pain, fibromyalgia, inflammatory disease, or neurological disease were included in the study. During their hospitalization, the intervention arm (n=44) received at least 2 daily sessions of music listening between D0 and D10, associated with their standard treatment, and then pursued the music intervention at home until D60 using a multimedia player in which the music listening software program had been installed. The control arm received standard treatment only (n=43). The end points measured at D0, D10, D60, and D90 were: pain (VAS), anxiety-depression (HAD) and the consumption of medication. At D60 in the music intervention arm, this technique enabled a more significant reduction (P<0.001) in pain (6.3 ± 1.7 at D0 vs. 3 ± 1.7 at D60) when compared with the arm without music intervention (6.2 ± 1.5 at D0 vs. 4.6 ± 1.7 at D60). In addition, music intervention contributed to significantly reducing both anxiety/depression and the consumption of anxiolytic agents. These results confirm the value of music intervention to the management of chronic pain and anxiety/depression. This music intervention method appears to be useful in managing chronic pain as it enables a significant reduction in the consumption of medication.

Sensitive determination of thiols in wine samples by a stable isotope-coded derivatization reagent d0/d4-acridone-10-ethyl-N-maleimide coupled with high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry analysis.

PubMed

Lv, Zhengxian; You, Jinmao; Lu, Shuaimin; Sun, Weidi; Ji, Zhongyin; Sun, Zhiwei; Song, Cuihua; Chen, Guang; Li, Guoliang; Hu, Na; Zhou, Wu; Suo, Yourui

2017-03-31

As the key aroma compounds, varietal thiols are the crucial odorants responsible for the flavor of wines. Quantitative analysis of thiols can provide crucial information for the aroma profiles of different wine styles. In this study, a rapid and sensitive method for the simultaneous determination of six thiols in wine using d 0 /d 4 -acridone-10-ethyl-N-maleimide (d 0 /d 4 -AENM) as stable isotope-coded derivatization reagent (SICD) by high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) has been developed. Quantification of thiols was performed by using d 4 -AENM labeled thiols as the internal standards (IS), followed by stable isotope dilution HPLC-ESI-MS/MS analysis. The AENM derivatization combined with multiple reactions monitoring (MRM) not only allowed trace analysis of thiols due to the extremely high sensitivity, but also efficiently corrected the matrix effects during HPLC-MS/MS and the fluctuation in MS/MS signal intensity due to instrument. The obtained internal standard calibration curves for six thiols were linear over the range of 25-10,000pmol/L (R 2 ≥0.9961). Detection limits (LODs) for most of analytes were below 6.3pmol/L. The proposed method was successfully applied for the simultaneous determination of six kinds of thiols in wine samples with precisions ≤3.5% and recoveries ≥78.1%. In conclusion, the developed method is expected to be a promising tool for detection of trace thiols in wine and also in other complex matrix. Copyright © 2017 Elsevier B.V. All rights reserved.

HFEM3D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weiss, Chester J

Software solves the three-dimensional Poisson equation div(k(grad(u)) = f, by the finite element method for the case when material properties, k, are distributed over hierarchy of edges, facets and tetrahedra in the finite element mesh. Method is described in Weiss, CJ, Finite element analysis for model parameters distributed on a hierarchy of geometric simplices, Geophysics, v82, E155-167, doi:10.1190/GEO2017-0058.1 (2017). A standard finite element method for solving Poisson’s equation is augmented by including in the 3D stiffness matrix additional 2D and 1D stiffness matrices representing the contributions from material properties associated with mesh faces and edges, respectively. The resulting linear systemmore » is solved iteratively using the conjugate gradient method with Jacobi preconditioning. To minimize computer storage for program execution, the linear solver computes matrix-vector contractions element-by-element over the mesh, without explicit storage of the global stiffness matrix. Program output vtk compliant for visualization and rendering by 3rd party software. Program uses dynamic memory allocation and as such there are no hard limits on problem size outside of those imposed by the operating system and configuration on which the software is run. Dimension, N, of the finite element solution vector is constrained by the the addressable space in 32-vs-64 bit operating systems. Total storage requirements for the problem. Total working space required for the program is approximately 13*N double precision words.« less

Dihedral angle principal component analysis of molecular dynamics simulations.

PubMed

Altis, Alexandros; Nguyen, Phuong H; Hegger, Rainer; Stock, Gerhard

2007-06-28

It has recently been suggested by Mu et al. [Proteins 58, 45 (2005)] to use backbone dihedral angles instead of Cartesian coordinates in a principal component analysis of molecular dynamics simulations. Dihedral angles may be advantageous because internal coordinates naturally provide a correct separation of internal and overall motion, which was found to be essential for the construction and interpretation of the free energy landscape of a biomolecule undergoing large structural rearrangements. To account for the circular statistics of angular variables, a transformation from the space of dihedral angles {phi(n)} to the metric coordinate space {x(n)=cos phi(n),y(n)=sin phi(n)} was employed. To study the validity and the applicability of the approach, in this work the theoretical foundations underlying the dihedral angle principal component analysis (dPCA) are discussed. It is shown that the dPCA amounts to a one-to-one representation of the original angle distribution and that its principal components can readily be characterized by the corresponding conformational changes of the peptide. Furthermore, a complex version of the dPCA is introduced, in which N angular variables naturally lead to N eigenvalues and eigenvectors. Applying the methodology to the construction of the free energy landscape of decaalanine from a 300 ns molecular dynamics simulation, a critical comparison of the various methods is given.

Preconditioning 2D Integer Data for Fast Convex Hull Computations

PubMed Central

2016-01-01

In order to accelerate computing the convex hull on a set of n points, a heuristic procedure is often applied to reduce the number of points to a set of s points, s ≤ n, which also contains the same hull. We present an algorithm to precondition 2D data with integer coordinates bounded by a box of size p × q before building a 2D convex hull, with three distinct advantages. First, we prove that under the condition min(p, q) ≤ n the algorithm executes in time within O(n); second, no explicit sorting of data is required; and third, the reduced set of s points forms a simple polygonal chain and thus can be directly pipelined into an O(n) time convex hull algorithm. This paper empirically evaluates and quantifies the speed up gained by preconditioning a set of points by a method based on the proposed algorithm before using common convex hull algorithms to build the final hull. A speedup factor of at least four is consistently found from experiments on various datasets when the condition min(p, q) ≤ n holds; the smaller the ratio min(p, q)/n is in the dataset, the greater the speedup factor achieved. PMID:26938221

Exact e-e (exchange) correlations of 2-D quantum dots in magnetic field: Size extensive N = 3 , 4 , … , ‧ n ‧ -electron systems via multi-pole expansion

NASA Astrophysics Data System (ADS)

Aggarwal, Priyanka; Sharma, Shivalika; Singh, Sunny; Kaur, Harsimran; Hazra, Ram Kuntal

2017-04-01

Inclusion of coulomb interaction emerges with the complexity of either convergence of integrals or separation of variables of Schrödinger equations. For an N-electron system, interaction terms grow by N(N-1)/2 factors. Therefore, 2-e system stands as fundamental basic unit for generalized N-e systems. For the first time, we have evaluated e-e correlations in very simple and absolutely terminating finite summed hypergeometric series for 2-D double carrier parabolic quantum dot in both zero and arbitrary non-zero magnetic field (symmetric gauge) and have appraised these integrals in variational methods. The competitive role among confinement strength, magnetic field, mass of the carrier and dielectric constant of the medium on energy level diagram, level-spacing statistics, heat capacities (Cv at 1 K) and magnetization (T ∼ (0-1)K) is studied on systems spanning over wide range of materials (GaAs,Ge,CdS,SiO2 and He, etc). We have also constructed an exact theory for generalized correlated N-e 2-D quantum dots via multi-pole expansion but for the sake of compactness of the article we refrain from data.

Interactions between barley grain processing and source of supplemental dietary fat on nitrogen metabolism and urea-nitrogen recycling in dairy cows.

PubMed

Gozho, G N; Hobin, M R; Mutsvangwa, T

2008-01-01

The objective of this study was to determine the effects of methods of barley grain processing and source of supplemental fat on urea-N transfer to the gastrointestinal tract (GIT) and the utilization of this recycled urea-N in lactating dairy cows. Four ruminally cannulated Holstein cows (656.3 +/- 27.7 kg of BW; 79.8 +/- 12.3 d in milk) were used in a 4 x 4 Latin square design with 28-d periods and a 2 x 2 factorial arrangement of dietary treatments. Experimental diets contained dry-rolled barley or pelleted barley in combination with whole canola or whole flaxseed as supplemental fat sources. Nitrogen balance was measured from d 15 to 19, with concurrent measurements of urea-N kinetics using continuous intrajugular infusions of [15N 15N]-urea. Dry matter intake and N intake were higher in cows fed dry-rolled barley compared with those fed pelleted barley. Nitrogen retention was not affected by diet, but fecal N excretion was higher in cows fed dry-rolled barley than in those fed pelleted barley. Actual and energy-corrected milk yield were not affected by diet. Milk fat content and milk fat yield were higher in cows fed dry-rolled barley compared with those fed pelleted barley. Source of supplemental fat did not affect urea-N kinetics. Urea-N production was higher (442.2 vs. 334.3 g of N/d), and urea-N entering the GIT tended to be higher (272.9 vs. 202.0 g of N/d), in cows fed dry-rolled barley compared with those fed pelleted barley. The amount of urea-N entry into the GIT that was returned to the ornithine cycle was higher (204.1 vs. 159.5 g of N/d) in cows fed dry-rolled barley than in pelleted barley-fed cows. The amount of urea-N recycled to the GIT and used for anabolic purposes, and the amounts lost in the urine or feces were not affected by dietary treatment. Microbial nonammonia N supply, estimated using total urinary excretion of purine derivatives, was not affected by diet. These results show that even though barley grain processing altered urea-N entry into the GIT, the utilization of this recycled urea-N for microbial production was unaffected as the additional urea-N, which entered the GIT was returned to ureagenesis.

Unilateral Outer Bow Expanded Cervical Headgear Force System: 3D Analysis Using Finite Element Method.

PubMed

Geramy, Allahyar; Mortezai, Omid; Esmaily, Masomeh; Darvishpour, Hojat

2015-04-01

Headgears are among the effective orthodontic appliances to achieve treatment goals. Unilateral molar distal movement is sometimes needed during an orthodontic treatment, which can be achieved by an asymmetric headgear. Different unilateral headgears have been introduced. The main goal of this study was to analyze the force system of unilateral expanded outer bow asymmetric headgears by the finite element method (FEM). Six 3D finite element models of a mesiodistal slice of the maxilla containing upper first molars, their periodontal ligaments (PDLs), cancellous bone, cortical bone, and a cervical headgear with expanded outer bow attached to maxillary first molars were designed in SolidWorks 2010 and meshed in ANSYS Workbench ver. 12.1. The models were the same except for the degree of outer bow expansion. The outer bow ends were loaded with 2 N force. The distal driving force and the net moment were evaluated. A decrease in the distalizing force in the normal side molar from 1.69 N to 1.37 N was shown by increasing the degree of unilateral expansion. At the same time, the force increased from 2.19 N to 2.49 N in the expanded side molar. A net moment increasing from 2.26 N.mm to 4.64 N.mm was also shown. Unilateral outer bow expansion can produce different distalizing forces in molars, which increase by increasing the expansion.

Comparison of precise orbit determination methods of zero-difference kinematic, dynamic and reduced-dynamic of GRACE-A satellite using SHORDE software

NASA Astrophysics Data System (ADS)

Li, Kai; Zhou, Xuhua; Guo, Nannan; Zhao, Gang; Xu, Kexin; Lei, Weiwei

2017-09-01

Zero-difference kinematic, dynamic and reduced-dynamic precise orbit determination (POD) are three methods to obtain the precise orbits of Low Earth Orbit satellites (LEOs) by using the on-board GPS observations. Comparing the differences between those methods have great significance to establish the mathematical model and is usefull for us to select a suitable method to determine the orbit of the satellite. Based on the zero-difference GPS carrier-phase measurements, Shanghai Astronomical Observatory (SHAO) has improved the early version of SHORDE and then developed it as an integrated software system, which can perform the POD of LEOs by using the above three methods. In order to introduce the function of the software, we take the Gravity Recovery And Climate Experiment (GRACE) on-board GPS observations in January 2008 as example, then we compute the corresponding orbits of GRACE by using the SHORDE software. In order to evaluate the accuracy, we compare the orbits with the precise orbits provided by Jet Propulsion Laboratory (JPL). The results show that: (1) If we use the dynamic POD method, and the force models are used to represent the non-conservative forces, the average accuracy of the GRACE orbit is 2.40cm, 3.91cm, 2.34cm and 5.17cm in radial (R), along-track (T), cross-track (N) and 3D directions respectively; If we use the accelerometer observation instead of non-conservative perturbation model, the average accuracy of the orbit is 1.82cm, 2.51cm, 3.48cm and 4.68cm in R, T, N and 3D directions respectively. The result shows that if we use accelerometer observation instead of the non-conservative perturbation model, the accuracy of orbit is better. (2) When we use the reduced-dynamic POD method to get the orbits, the average accuracy of the orbit is 0.80cm, 1.36cm, 2.38cm and 2.87cm in R, T, N and 3D directions respectively. This method is carried out by setting up the pseudo-stochastic pulses to absorb the errors of atmospheric drag and other perturbations. (3) If we use the kinematic POD method, the accuracy of the GRACE orbit is 2.92cm, 2.48cm, 2.76cm and 4.75cm in R, T, N and 3D directions respectively. In conclusion, it can be seen that the POD of GRACE satellite is practicable by using different strategies and methods. The orbit solution is well and stable, they all can obtain the GRACE orbits with centimeter-level precision.

Baryon interactions from lattice QCD with physical masses — strangeness S = -1 sector —

NASA Astrophysics Data System (ADS)

Nemura, Hidekatsu; Aoki, Sinya; Doi, Takumi; Gongyo, Shinya; Hatsuda, Tetsuo; Ikeda, Yoichi; Inoue, Takashi; Iritani, Takumi; Ishii, Noriyoshi; Miyamoto, Takaya; Sasaki, Kenji

2018-03-01

We present our recent results of baryon interactions with strangeness S = -1 based on Nambu-Bethe-Salpeter (NBS) correlation functions calculated fromlattice QCD with almost physical quark masses corresponding to (mk,mk) ≈ (146, 525) MeV and large volume (La)4 ≈ (96a)4 ≈ (8.1 fm)4. In order to perform a comprehensive study of baryon interactions, a large number of NBS correlation functions from NN to ΞΞ are calculated simultaneously by using large scale computer resources. In this contribution, we focus on the strangeness S = -1 channels of the hyperon interactions by means of HAL QCD method. Four sets of three potentials (the 3S1 - 3 D1 central, 3S1 - 3 D1 tensor, and the 1S0 central potentials) are presented for the ∑N - ∑N (the isospin I = 3/2) diagonal, the ∧N - ∧N diagonal, the ∧N → ∑N transition, and the ∑N - ∑N (I = 1/2) diagonal interactions. Scattering phase shifts for ∑N (I = 3/2) system are presented.

No association of dietary fiber intake with inflammation or arterial stiffness in youth with type 1 diabetes

PubMed Central

Jaacks, Lindsay M.; Crandell, Jamie; Liese, Angela D.; Lamichhane, Archana P.; Bell, Ronny A.; Dabelea, Dana; D'Agostino, Ralph B.; Dolan, Lawrence M.; Marcovina, Santica; Reynolds, Kristi; Shah, Amy S.; Urbina, Elaine M.; Wadwa, R. Paul; Mayer-Davis, Elizabeth J.

2014-01-01

Aim To examine the association of dietary fiber intake with inflammation and arterial stiffness among youth with type 1 diabetes (T1D) in the US. Methods Data are from youth ≥ 10 years old with clinically diagnosed T1D for ≥ 3 months and ≥ 1 positive diabetes autoantibody in the SEARCH for Diabetes in Youth Study. Fiber intake was assessed by food frequency questionnaire with measurement error (ME) accounted for by structural sub-models derived using additional 24-hour dietary recall data in a calibration sample and the respective exposure-disease model covariates. Markers of inflammation, measured at baseline, included IL-6 (n=1405), CRP (n=1387), and fibrinogen (n=1340); markers of arterial stiffness, measured approximately 19 months post-baseline, were available in a subset of participants and included augmentation index (n=180), pulse wave velocity (n=184), and brachial distensibility (n=177). Results Mean (SD) T1D duration was 47.9 (43.2) months; 12.5% of participants were obese. Mean (SD) ME-adjusted fiber intake was 15 (2.8) g/day. In multivariable analyses, fiber intake was not associated with inflammation or arterial stiffness. Conclusion Among youth with T1D, fiber intake does not meet recommendations and is not associated with measures of systemic inflammation or vascular stiffness. Further research is needed to evaluate whether fiber is associated with these outcomes in older individuals with T1D or among individuals with higher intakes than those observed in the present study. PMID:24613131

A Mixed-Methods Analysis in Assessing Students' Professional Development by Applying an Assessment for Learning Approach.

PubMed

Peeters, Michael J; Vaidya, Varun A

2016-06-25

Objective. To describe an approach for assessing the Accreditation Council for Pharmacy Education's (ACPE) doctor of pharmacy (PharmD) Standard 4.4, which focuses on students' professional development. Methods. This investigation used mixed methods with triangulation of qualitative and quantitative data to assess professional development. Qualitative data came from an electronic developmental portfolio of professionalism and ethics, completed by PharmD students during their didactic studies. Quantitative confirmation came from the Defining Issues Test (DIT)-an assessment of pharmacists' professional development. Results. Qualitatively, students' development reflections described growth through this course series. Quantitatively, the 2015 PharmD class's DIT N2-scores illustrated positive development overall; the lower 50% had a large initial improvement compared to the upper 50%. Subsequently, the 2016 PharmD class confirmed these average initial improvements of students and also showed further substantial development among students thereafter. Conclusion. Applying an assessment for learning approach, triangulation of qualitative and quantitative assessments confirmed that PharmD students developed professionally during this course series.

Health-state utilities in a prisoner population: a cross-sectional survey

PubMed Central

Chong, Christopher AKY; Li, Sicong; Nguyen, Geoffrey C; Sutton, Andrew; Levy, Michael H; Butler, Tony; Krahn, Murray D; Thein, Hla-Hla

2009-01-01

Background Health-state utilities for prisoners have not been described. Methods We used data from a 1996 cross-sectional survey of Australian prisoners (n = 734). Respondent-level SF-36 data was transformed into utility scores by both the SF-6D and Nichol's method. Socio-demographic and clinical predictors of SF-6D utility were assessed in univariate analyses and a multivariate general linear model. Results The overall mean SF-6D utility was 0.725 (SD 0.119). When subdivided by various medical conditions, prisoner SF-6D utilities ranged from 0.620 for angina to 0.764 for those with none/mild depressive symptoms. Utilities derived by the Nichol's method were higher than SF-6D scores, often by more than 0.1. In multivariate analysis, significant independent predictors of worse utility included female gender, increasing age, increasing number of comorbidities and more severe depressive symptoms. Conclusion The utilities presented may prove useful for future economic and decision models evaluating prison-based health programs. PMID:19715571

FTIR, FT-RAMAN, NMR, spectra, normal co-ordinate analysis, NBO, NLO and DFT calculation of N,N-diethyl-4-methylpiperazine-1-carboxamide molecule.

PubMed

Muthu, S; Elamurugu Porchelvi, E

2013-11-01

The Fourier Transform Infrared (FT-IR) and FT-Raman of N,N-diethyl-4-methylpiperazine-1-carboxamide (NND4MC) have been recorded and analyzed. The structure of the compound was optimized and the structural characteristics were determined by density functional theory (DFT) using B3LYP method with 6-31G(d,p) and 6-311G(d,p) basis sets. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. The theoretically predicted FT-IR and FT-Raman spectra of the title molecule have been constructed. The detailed interpretation of the vibrational spectra has been carried out with aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The results show that electron density (ED) in the σ(*) and π(*) antibonding orbitals and second order delocalization energies (E2) confirm the occurrence of intramolecular charge transfer (ICT) within the molecule. The electronic dipole moment (μD) and the first hyperpolarizability (βtot) values of the investigated molecule were computed using Density Functional Theory (DFT/B3LYP) with 6-31G(d,p) and 6-311G(d,p) basis sets. The calculated results also show that the NND4MC molecule may have microscopy nonlinear optical (NLO) behavior with non zero values. Mulliken atomic charges of NND4MC were calculated. The (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results. The UV-Vis spectrum of the compound was recorded. The theoretical electronic absorption spectra have been calculated by using CIS, TD-DFT methods. A study on the electronic properties, such as HOMO and LUMO energies, molecular electrostatic potential (MEP) were also performed. Copyright © 2013 Elsevier B.V. All rights reserved.

Initial simulated FFR investigation using flow measurements in patient-specific 3D printed coronary phantoms

NASA Astrophysics Data System (ADS)

Shepard, Lauren; Sommer, Kelsey; Izzo, Richard; Podgorsak, Alexander; Wilson, Michael; Said, Zaid; Rybicki, Frank J.; Mitsouras, Dimitrios; Rudin, Stephen; Angel, Erin; Ionita, Ciprian N.

2017-03-01

Purpose: Accurate patient-specific phantoms for device testing or endovascular treatment planning can be 3D printed. We expand the applicability of this approach for cardiovascular disease, in particular, for CT-geometry derived benchtop measurements of Fractional Flow Reserve, the reference standard for determination of significant individual coronary artery atherosclerotic lesions. Materials and Methods: Coronary CT Angiography (CTA) images during a single heartbeat were acquired with a 320x0.5mm detector row scanner (Toshiba Aquilion ONE). These coronary CTA images were used to create 4 patientspecific cardiovascular models with various grades of stenosis: severe, <75% (n=1); moderate, 50-70% (n=1); and mild, <50% (n=2). DICOM volumetric images were segmented using a 3D workstation (Vitrea, Vital Images); the output was used to generate STL files (using AutoDesk Meshmixer), and further processed to create 3D printable geometries for flow experiments. Multi-material printed models (Stratasys Connex3) were connected to a programmable pulsatile pump, and the pressure was measured proximal and distal to the stenosis using pressure transducers. Compliance chambers were used before and after the model to modulate the pressure wave. A flow sensor was used to ensure flow rates within physiological reported values. Results: 3D model based FFR measurements correlated well with stenosis severity. FFR measurements for each stenosis grade were: 0.8 severe, 0.7 moderate and 0.88 mild. Conclusions: 3D printed models of patient-specific coronary arteries allows for accurate benchtop diagnosis of FFR. This approach can be used as a future diagnostic tool or for testing CT image-based FFR methods.

Oncoprotein protein kinase

DOEpatents

Karin, Michael; Hibi, Masahiko; Lin, Anning

1997-01-01

An isolated polypeptide (JNK) characterized by having a molecular weight of 46kD as determined by reducing SDS-PAGE, having serine and threonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Oncoprotein protein kinase antibody kit

DOEpatents

Karin, Michael [San Diego, CA; Hibi, Masahiko [San Diego, CA; Lin, Anning [La Jolla, CA

2008-12-23

An isolated polypeptide (JNK) characterized by having a molecular weight of 46 kD as determined by reducing SDS-PAGE, having serine and threonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Oncoprotein protein kinase

DOEpatents

Karin, Michael; Hibi, Masahiko; Lin, Anning; Davis, Roger; Derijard, Benoit

2003-02-04

An isolated polypeptide (JNK) characterized by having a molecular weight of 46kD as determined by reducing SDS-PAGE, having serine and threonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Oncoprotein protein kinase

DOEpatents

Karin, Michael; Hibi, Masahiko; Lin, Anning

1997-01-01

An isolated polypeptide (JNK) characterized by having a molecular weight of 46 kD as determined by reducing SDS-PAGE, having serine and threonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Oncoprotein protein kinase

DOEpatents

Karin, Michael; Hibi, Masahiko; Lin, Anning

1998-01-01

An isolated polypeptide (JNK) characterized by having a molecular weight of 46 kD as determined by reducing SDS-PAGE, having serine and threonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Comparison of a low- to high-confinement transition theory with experimental data from DIII-D.

PubMed

Guzdar, P N; Kleva, R G; Groebner, R J; Gohil, P

2002-12-23

From our recent theory based on the generation of shear flow and field in finite beta plasmas, the criterion for bifurcation from low to high confinement mode yields a critical parameter proportional to T(e)/square root (L(n)), where T(e) is the electron temperature and L(n) is the density scale length. The predicted threshold shows very good agreement with edge measurements on discharges undergoing low-to-high transitions in DIII-D. The observed differences in the transitions with the reversal of the toroidal magnetic field are reconciled in terms of this critical parameter. The theory also provides an explanation for pellet injection H modes in DIII-D, thereby unifying unconnected methods for accomplishing the transition.

BiliChek transcutaneous bilirubin meter overestimates serum bilirubin as measured by the Doumas reference method.

PubMed

Karon, Brad S; Wickremasinghe, Andrea C; Lo, Stanley F; Saenger, Amy K; Cook, Walter J

2010-08-01

To determine the relationship between BiliChek TcB (Respironics, Marietta GA) and Doumas reference serum or plasma total bilirubin (TSB). Pooled samples with values assigned by the Doumas reference method were used to establish the relationship between a local laboratory and reference Doumas TSB. We then established the relationship between TcB and TSB in the 3 months before and after reassignment of calibrator setpoints undertaken to match the local laboratory to Doumas reference bilirubin values. Before calibrator setpoint reassignment TSB as measured in our laboratory overestimated Doumas reference bilirubin. After calibrator adjustment laboratory TSB was within 1.7-6.8 micromol/L (0.1-0.4 mg/dL) of Doumas reference values. Mean bias between BiliChek TcB and TSB was 42.8+/-22.2 micromol/L (2.5+/-1.3mg/dL) (n=94) before and 49.6+/-22.2 micromol/L (2.9+/-1.3mg/dL) (n=115) after calibration adjustment. BiliChek TcB significantly overestimates TSB as measured by the Doumas reference method. 2010 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Differences between Cheddar cheese manufactured by the milled-curd and stirred-curd methods using different commercial starters.

PubMed

Shakeel-ur-Rehman; Drake, M A; Farkye, N Y

2008-01-01

Traditionally, Cheddar cheese is made by the milled-curd method. However, because of the mechanization of cheese making and time constraints, the stirred-curd method is more commonly used by many large-scale commercial manufacturers. This study was undertaken to evaluate quality differences during ripening (at 2 and 8 degrees C) of Cheddar cheese made by the milled-curd and stirred-curd methods, using 4 different commercial starters. Twenty-four vats (4 starters x 2 methods x 3 replicates) were made, with approximately 625 kg of pasteurized (72 degrees C x 16 s) whole milk in each vat. Fat, protein, and salt contents of the cheeses were not affected by the starter. Starter cell densities in cheese were not affected by the method of manufacture. Nonstarter lactic acid bacteria counts at 90, 180, and 270 d were influenced by the manufacturing method, with a higher trend in milled-curd cheeses. Proteolysis in cheese (percentage of water-soluble N) was influenced by the starter and manufacturing method (270 d). Sensory analysis by a trained descriptive panel (n = 8) revealed differences in cooked, whey, sulfur, brothy, milk fat, umami, and bitter attributes caused by the starter, whereas only brothy flavor was influenced by storage temperature. The method of manufacture influenced diacetyl, sour, and salty flavors.

Enzymatic synthesis of novel oligosaccharides from N-acetylsucrosamine using β-fructofuranosidase from Aspergillus oryzae.

PubMed

Nishio, Toshiyuki; Juami, Mai; Wada, Toru; Sugimoto, Yuta; Senou, Hiroki; Komori, Wataru; Sakuma, Chiseko; Hirano, Takako; Hakamata, Wataru; Tashiro, Mitsuru

2013-12-15

Mycelia of Aspergillus oryzae NBRC100959 contain 2 types of β-fructofuranosidases, transfructosylation-catalyzing enzyme (βFFaseI), and hydrolysis-catalyzing enzyme (βFFaseII). Using βFFaseI extracted from the mycelia of strain NBRC100959, two novel oligosaccharides consisting of GlcNAc and fructose, β-d-fructofuranosyl-(2→1)-β-d-fructofuranosyl-(2↔1)-2-acetamido-2-deoxy-α-d-glucopyranoside (N-acetyl-1-kestosamine, 1-KesNAc) and β-d-fructofuranosyl-(2→1)-β-d-fructofuranosyl-(2→1)-β-d-fructofuranosyl-(2↔1)-2-acetamido-2-deoxy-α-d-glucopyranoside (N-acetylnystosamine, NysNAc), were synthesized from β-d-fructofuranosyl-(2↔1)-2-acetamido-2-deoxy-α-d-glucopyranoside (N-acetylsucrosamine, SucNAc). We next planned to synthesize 1-KesNAc and NysNAc using A. oryzae mycelia. However, it was thought that the presence of βFFaseII is disadvantageous for the production of these oligosaccharides by βFFaseI, because βFFaseII hydrolyzed 1-KesNAc and NysNAc. We succeeded to produce A. oryzae mycelia containing βFFaseI as the major β-fructofuranosidase, by increasing sucrose concentration in the culture medium. Then, using a dried sample of these A. oryzae mycelia, reaction for the oligosaccharide production was performed. As the results, 190mg of 1-KesNAc and 60mg of NysNAc were obtained from 0.6g of SucNAc. This whole-cell catalysis method facilitates the synthesis of 1-KesNAc and NysNAc because extraction and purification of βFFaseI from mycelia are unnecessary. Copyright © 2013 Elsevier Ltd. All rights reserved.

CHANGES IN LEVELS OF D1, D2, OR NMDA RECEPTORS DURING WITHDRAWAL FROM BRIEF OR EXTENDED DAILY ACCESS TO IV COCAINE

PubMed Central

Ben-Shahar, Osnat; Keeley, Patrick; Cook, Mariana; Brake, Wayne; Joyce, Megan; Nyffeler, Myriel; Heston, Rebecca; Ettenberg, Aaron

2007-01-01

We previously reported that brief (1 hr), but not extended (6 hrs), daily access to cocaine results in a sensitized locomotor response to cocaine and in elevated c-Fos immunoreactivity and DAT binding in the nucleus accumbens (N.Acc) core. In order to better our understanding of the neural adaptations mediating the transition from controlled drug-use to addiction, the current experiments were set to further explore the neural adaptations resulting from these two access conditions. Rats received either brief daily access to saline or cocaine, or brief daily access followed by extended daily access, to cocaine. Subjects were then sacrificed either 20 minutes, or 14 or 60 days, after the last self-administration session. Samples of the ventral tegmental area (VTA), N.Acc core and shell, dorsal striatum, and medial prefrontal cortex (mPFC) were taken for analysis of D1 ([3H]SCH-23390), D2 ([3H]Spiperone), and NMDA ([3H]MK-801) receptor binding (using the method of receptor autoradiography). At 20 minutes into withdrawal D2 receptors were elevated and NMDA receptors were reduced in the mPFC of the brief access animals while D1 receptors were elevated in the N.Acc shell of the extended access animals, compared to saline controls. D2 receptors were reduced in the N.Acc shell of the brief access animals compared to saline controls after 14 days, and compared to extended access animals after 60 days of withdrawal. In summary, extended access to cocaine resulted in only transient changes in D1 receptors binding. These results suggest that the development of compulsive drug use is largely unrelated to changes in total binding of D2 or NMDA receptors. PMID:17161392

Short communication: Supplementing grape marc to cows fed a pasture-based diet as a method to alter nitrogen partitioning and excretion.

PubMed

Greenwood, S L; Edwards, G R; Harrison, R

2012-02-01

The inclusion of the grape marc into livestock rations provides an opportunity not only to use a waste byproduct resourcefully, but also to induce beneficial metabolic changes in animals. Grape marc contains condensed tannins that could alter N metabolism, which would be beneficial from an environmental perspective. The objective was to determine if dietary grape marc could decrease urinary N excretion from nonlactating dairy cattle. Eighteen multiparous cows were randomly divided into 2 equal groups, receiving either (1) pasture+2 kg of dry matter (DM)/d energy pellet per cow (control group) or (2) pasture+2 kg of DM/d energy pellet per cow+3 kg of DM/d grape marc per cow. Urine, fecal, and blood samples were collected at baseline (d 0) and at d 9. Cows receiving grape marc excreted 22% more N in feces compared with the control group. Cows offered grape marc had lower plasma urea nitrogen concentrations (2.42 and 2.97±0.1 mmol/L from treatment and control cows, respectively), but had no significant difference in urine urea concentration compared with control animals (84.24 and 114.1±17.62 mmol/L from treatment and control cows, respectively). Overall, the potential exists to alter N metabolism in dairy cows using dietary grape marc. The exact mechanisms causing this shift in N metabolism require further investigation. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

High Precision 2-D Grating Groove Density Measurement

NASA Astrophysics Data System (ADS)

Zhang, Ningxiao; McEntaffer, Randall; Tedesco, Ross

2017-08-01

Our research group at Penn State University is working on producing X-ray reflection gratings with high spectral resolving power and high diffraction efficiency. To estimate our fabrication accuracy, we apply a precise 2-D grating groove density measurement to plot groove density distributions of gratings on 6-inch wafers. In addition to plotting a fixed groove density distribution, this method is also sensitive to measuring the variation of the groove density simultaneously. This system can reach a measuring accuracy (ΔN/N) of 10-3. Here we present this groove density measurement and some applications.

Toward holographic reconstruction of bulk geometry from lattice simulations

NASA Astrophysics Data System (ADS)

Rinaldi, Enrico; Berkowitz, Evan; Hanada, Masanori; Maltz, Jonathan; Vranas, Pavlos

2018-02-01

A black hole described in SU( N ) gauge theory consists of N D-branes. By separating one of the D-branes from others and studying the interaction between them, the black hole geometry can be probed. In order to obtain quantitative results, we employ the lattice Monte Carlo simulation. As a proof of the concept, we perform an explicit calculation in the matrix model dual to the black zero-brane in type IIA string theory. We demonstrate this method actually works in the high temperature region, where the stringy correction is large. We argue possible dual gravity interpretations.

Identification of ω-N-Methyl-4-hydroxytryptamine (Norpsilocin) as a Psilocybe Natural Product.

PubMed

Lenz, Claudius; Wick, Jonas; Hoffmeister, Dirk

2017-10-27

We report the identification of ω-N-methyl-4-hydroxytryptamine (norpsilocin, 1) from the carpophores of the hallucinogenic mushroom Psilocybe cubensis. The structure was elucidated by 1D and 2D NMR spectroscopy and high-resolution mass spectrometry. Norpsilocin has not previously been reported as a natural product. It likely represents the actual psychotropic agent liberated from its 4-phosphate ester derivative, the known natural product baeocystin. We further present a simple and artifact-free extraction method that prevents dephosphorylation and therefore helps reflect the naturally occurring metabolic profile of Psilocybe mushrooms in subsequent analyses.

Toward holographic reconstruction of bulk geometry from lattice simulations

DOE PAGES

Rinaldi, Enrico; Berkowitz, Evan; Hanada, Masanori; ...

2018-02-07

A black hole described in SU(N ) gauge theory consists of N D-branes. By separating one of the D-branes from others and studying the interaction between them, the black hole geometry can be probed. In order to obtain quantitative results, we employ the lattice Monte Carlo simulation. As a proof of the concept, we perform an explicit calculation in the matrix model dual to the black zero-brane in type IIA string theory. We demonstrate this method actually works in the high temperature region, where the stringy correction is large. We argue possible dual gravity interpretations.

Synergy of the Developed 6D BIM Framework and Conception of the nD BIM Framework and nD BIM Process Ontology

ERIC Educational Resources Information Center

O'Keeffe, Shawn Edward

2013-01-01

The author developed a unified nD framework and process ontology for Building Information Modeling (BIM). The research includes a framework developed for 6D BIM, nD BIM, and nD ontology that defines the domain and sub-domain constructs for future nD BIM dimensions. The nD ontology defines the relationships of kinds within any new proposed…

Bayesian Estimation of Thermonuclear Reaction Rates for Deuterium+Deuterium Reactions

NASA Astrophysics Data System (ADS)

Gómez Iñesta, Á.; Iliadis, C.; Coc, A.

2017-11-01

The study of d+d reactions is of major interest since their reaction rates affect the predicted abundances of D, 3He, and 7Li. In particular, recent measurements of primordial D/H ratios call for reduced uncertainties in the theoretical abundances predicted by Big Bang nucleosynthesis (BBN). Different authors have studied reactions involved in BBN by incorporating new experimental data and a careful treatment of systematic and probabilistic uncertainties. To analyze the experimental data, Coc et al. used results of ab initio models for the theoretical calculation of the energy dependence of S-factors in conjunction with traditional statistical methods based on χ 2 minimization. Bayesian methods have now spread to many scientific fields and provide numerous advantages in data analysis. Astrophysical S-factors and reaction rates using Bayesian statistics were calculated by Iliadis et al. Here we present a similar analysis for two d+d reactions, d(d, n)3He and d(d, p)3H, that has been translated into a total decrease of the predicted D/H value by 0.16%.

Guide Manual of Cooling Methods for Electronic Equipment

DTIC Science & Technology

1955-03-31

CLEVELAND, OHIO BUREAU OF SHIPS tu OfNAVY DEPARTMENT WASHINGTON 25, D. C, ,:o : M ,, ,,,,;,;,,--r t 1oeipii;; n .. , , .M.-- .,., itti,.’( Best Available Copy...Tube Circuits 167 56. Pressure Temperature Relationshio of "Freon" com- 190 pounds 57. Fluorochemical N -h3 Vapor Pressure - Temperature 191 58...Fluorochemical N -43 Temperature vs. Density - 192 Viscosity 59. Fluorochemical 0-75 Vapor Pressure - Temperature 193 60. Fluorochemical 0-75 Temperature vs

Chemo- and Diastereoselective N-Heterocyclic Carbene-Catalyzed Cross-Benzoin Reactions Using N-Boc-α-amino Aldehydes.

PubMed

Haghshenas, Pouyan; Gravel, Michel

2016-09-16

N-Boc-α-amino aldehydes are shown to be excellent partners in cross-benzoin reactions with aliphatic or heteroaromatic aldehydes. The chemoselectivity of the reaction and the facial selectivity on the amino aldehyde allow cross-benzoin products to be obtained in good yields and good diastereomeric ratios. The developed method is utilized as the key step in a concise total synthesis of d-arabino-phytosphingosine.

Short Note on Complexity of Multi-Value Byzantine Agreement

DTIC Science & Technology

2010-07-27

which lead to nBl /D bits over the whole algorithm. Broadcasts in extended step: In the extended step, every node broadcasts D bits. Thus nDB bits...bits, as: (n− 1)l + n(n− 1)(k +D/k)l/D + nBl /D + nDBt(t+ 1) (4) = (n− 1)l +O(n2kl/D + n2l/k + nBl /D + n3BD). (5) Notice that broadcast algorithm of

Digital Logic and Reconfigurable Interconnects Using Aluminum Gallium Arsenide Electro-Optic Fredkin Gates

DTIC Science & Technology

1994-06-01

length and coupling coefficient for the zero-gap directional coupler are obtained by using Eq. 3.2.39. Bums and Milton Effective Index Method In a 1975...nj) with •i wavegulde thicness b. Effective index N1 is then used to find the effective >Vt.,:, ;- 105 c a ¶ 2 n. n_ z n2 - : n4 Three-Dimensional...constant for the TM, modes is determined in a manner similar to the one used for the TEp modes. First, effective index N1 of 2-D Waveguide I is found by

Three-Dimensional Unsteady Separation at Low Reynolds Numbers

DTIC Science & Technology

1990-07-01

novel, robust adaptive- grid technique for incompressible flow (Shen & Reed 1990a "Shepard’s Interpolation for Solution-Adaptive Methods" submitted to...3-D adaptive- grid schemes developed for flat plate for full, unsteady, incompressible Navier Stokes. 4. 2-D and 3-D unsteady, vortex-lattice code...perforated to tailor suction through wall. Honeycomb and contractiong uide flow uniformly crons "a dn muwet a m Fiur32 c ic R n R ev lving -disc seals

Differentiated human airway organoids to assess infectivity of emerging influenza virus.

PubMed

Zhou, Jie; Li, Cun; Sachs, Norman; Chiu, Man Chun; Wong, Bosco Ho-Yin; Chu, Hin; Poon, Vincent Kwok-Man; Wang, Dong; Zhao, Xiaoyu; Wen, Lei; Song, Wenjun; Yuan, Shuofeng; Wong, Kenneth Kak-Yuen; Chan, Jasper Fuk-Woo; To, Kelvin Kai-Wang; Chen, Honglin; Clevers, Hans; Yuen, Kwok-Yung

2018-06-26

Novel reassortant avian influenza H7N9 virus and pandemic 2009 H1N1 (H1N1pdm) virus cause human infections, while avian H7N2 and swine H1N1 virus mainly infect birds and pigs, respectively. There is no robust in vitro model for assessing the infectivity of emerging viruses in humans. Based on a recently established method, we generated long-term expanding 3D human airway organoids which accommodate four types of airway epithelial cells: ciliated, goblet, club, and basal cells. We report differentiation conditions which increase ciliated cell numbers to a nearly physiological level with synchronously beating cilia readily discernible in every organoid. In addition, the differentiation conditions induce elevated levels of serine proteases, which are essential for productive infection of human influenza viruses and low-pathogenic avian influenza viruses. We also established improved 2D monolayer culture conditions for the differentiated airway organoids. To demonstrate the ability of differentiated airway organoids to identify human-infective virus, 3D and 2D differentiated airway organoids are applied to evaluate two pairs of viruses with known distinct infectivity in humans, H7N9/Ah versus H7N2 and H1N1pdm versus an H1N1 strain isolated from swine (H1N1sw). The human-infective H7N9/Ah virus replicated more robustly than the poorly human-infective H7N2 virus; the highly human-infective H1N1pdm virus replicated to a higher titer than the counterpart H1N1sw. Collectively, we developed differentiated human airway organoids which can morphologically and functionally simulate human airway epithelium. These differentiated airway organoids can be applied for rapid assessment of the infectivity of emerging respiratory viruses to human. Copyright © 2018 the Author(s). Published by PNAS.

Real-time 3D transesophageal echocardiography for the evaluation of rheumatic mitral stenosis.

PubMed

Schlosshan, Dominik; Aggarwal, Gunjan; Mathur, Gita; Allan, Roger; Cranney, Greg

2011-06-01

The aims of this study were: 1) to assess the feasibility and reliability of performing mitral valve area (MVA) measurements in patients with rheumatic mitral valve stenosis (RhMS) using real-time 3-dimensional transesophageal echocardiography (3DTEE) planimetry (MVA(3D)); 2) to compare MVA(3D) with conventional techniques: 2-dimensional (2D) planimetry (MVA(2D)), pressure half-time (MVA(PHT)), and continuity equation (MVA(CON)); and 3) to evaluate the degree of mitral commissural fusion. 3DTEE is a novel technique that provides excellent image quality of the mitral valve. Real-time 3DTEE is a relatively recent enhancement of this technique. To date, there have been no feasibility studies investigating the utility of real-time 3DTEE in the assessment of RhMS. Forty-three consecutive patients referred for echocardiographic evaluation of RhMS and suitability for percutaneous mitral valvuloplasty were assessed using 2D transthoracic echocardiography and real-time 3DTEE. MVA(3D), MVA(2D), MVA(PHT), MVA(CON), and the degree of commissural fusion were evaluated. MVA(3D) assessment was possible in 41 patients (95%). MVA(3D) measurements were significantly lower compared with MVA(2D) (mean difference: -0.16 ± 0.22; n=25, p<0.005) and MVA(PHT) (mean difference: -0.23 ± 0.28 cm(2); n=39, p<0.0001) but marginally greater than MVA(CON) (mean difference: 0.05 ± 0.22 cm(2); n=24, p=0.82). MVA(3D) demonstrated best agreement with MVA(CON) (intraclass correlation coefficient [ICC] 0.83), followed by MVA(2D) (ICC 0.79) and MVA(PHT) (ICC 0.58). Interobserver and intraobserver agreement was excellent for MVA(3D), with ICCs of 0.93 and 0.96, respectively. Excellent commissural evaluation was possible in all patients using 3DTEE. Compared with 3DTEE, underestimation of the degree of commissural fusion using 2D transthoracic echocardiography was observed in 19%, with weak agreement between methods (κ<0.4). MVA planimetry is feasible in the majority of patients with RhMS using 3DTEE, with excellent reproducibility, and compares favorably with established methods. Three-dimensional transesophageal echocardiography allows excellent assessment of commissural fusion. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

The 6-31B(d) basis set and the BMC-QCISD and BMC-CCSD multicoefficient correlation methods.

PubMed

Lynch, Benjamin J; Zhao, Yan; Truhlar, Donald G

2005-03-03

Three new multicoefficient correlation methods (MCCMs) called BMC-QCISD, BMC-CCSD, and BMC-CCSD-C are optimized against 274 data that include atomization energies, electron affinities, ionization potentials, and reaction barrier heights. A new basis set called 6-31B(d) is developed and used as part of the new methods. BMC-QCISD has mean unsigned errors in calculating atomization energies per bond and barrier heights of 0.49 and 0.80 kcal/mol, respectively. BMC-CCSD has mean unsigned errors of 0.42 and 0.71 kcal/mol for the same two quantities. BMC-CCSD-C is an equally effective variant of BMC-CCSD that employs Cartesian rather than spherical harmonic basis sets. The mean unsigned error of BMC-CCSD or BMC-CCSD-C for atomization energies, barrier heights, ionization potentials, and electron affinities is 22% lower than G3SX(MP2) at an order of magnitude less cost for gradients for molecules with 9-13 atoms, and it scales better (N6 vs N,7 where N is the number of atoms) when the size of the molecule is increased.

The evaluation of a new method to extract spectroscopic factors using asymptotic normalization coefficients and the astrophysical ^14C(n,γ)^15C reaction rate

NASA Astrophysics Data System (ADS)

McCleskey, M.; Mukhamedzhanov, A. M.; Trache, L.; Banu, A.; Goldberg, V.; Roeder, B. T.; Simmons, E. N.; Spiridon, A.; Tribble, R. E.

2011-10-01

A new method to determine spectroscopic factors (SFs) that utilizes asymptotic normalization coefficients (ANCs) has been tested at Texas A&M, using ^15C as a test case. The method would use the ANC to fix the external contribution to a non-peripheral reaction which would otherwise be free to vary to unphysical values in a traditional approach. The investigation consisted of two parts. First, the ANC for the ^14C+n configuration in ^15C was determined from the heavy ion neutron transfer reaction ^13C(^14C,^15C)^12C and the inverse kinematics reaction d(^14C,p)^15C. Both of these reactions were measured at sufficiently low energy to be peripheral. Next, a non-peripheral reaction ^14C(d,p)^15C was measured with an incident deuteron energy of 60 MeV, and this reaction was used along with the previously determined ANC to attempt to find the SF. The ANC was also used to calculate the astrophysical neutron direct capture rate for ^14C(n,γ)^15C, which was compared with recent direct experimental results.

Electron spectroscopic determinations of M and N core-hole lifetimes for the elements Nb-Te (Z=41-52)

NASA Astrophysics Data System (ADS)

Mårtensson, Nils; Nyholm, Ralf

1981-12-01

Photoelectron spectroscopy has been used to determine M and N core-level widths for the elements Nb-Te (Z=41-52). The analysis is based on direct comparisons of the lifetime contributions to different core levels. Absolute determinations are made for the narrow 3d levels. In the metals Nb-Rh (Z=41-45) an M4M5N45 Coster-Kronig decay channel is observed through a broadening of the 3d32 core-electron lines. The rate of this Coster-Kronig process is found to have its maximum for Ru and Rh. For Pd a much reduced, but still significant, broadening of the 3d32 level is detected. This observation is discussed in terms of itinerant versus quasiatomic contributions to the Coster-Kronig process. For Z>=47 (Ag) the Coster-Kronig channel is closed. For Nb-Rh the M4M5N45 process can be used for absolute determinations of the 3d linewidths. In this connection also the properties of the M45N45N45 Auger process are discussed. The accuracy of the present method makes it possible to investigate small differences between the 3p12 and 3p32 level widths. For several elements the unusual result is obtained that the 3p32 level is broader than the 3p12 level. This finding is in good agreement with theoretical predictions. The 4s and 4p spectra of the currently investigated elements are strongly influenced by configuration-interaction (CI) effects. However, the 4s line shapes are found to be quite normal for all the 5th-period elements. For Z<=45 (Rh) the 4p12 level is found to be broadened due to N2N3N45 super-Coster-Kronig processes. For Z<=46 (Pd) the shape of the 4p32 core-electron lines can reasonably well be reproduced by broadened 3d52 line profiles. For Z>=47 (Ag) this can, however, not be achieved. This marks a transition into a region of Z values where CI effects become particularly important. The accuracy of the present method for determining core-level widths can be judged from a comparison between our analysis of the 4p levels and x-ray studies of the Mζ transition. The results indicate that core-level widths can be determined with an accuracy of about 0.2 eV even for fairly broad and asymmetric electron lines.

Giant piezoelectricity in potassium-sodium niobate lead-free ceramics.

PubMed

Wang, Xiaopeng; Wu, Jiagang; Xiao, Dingquan; Zhu, Jianguo; Cheng, Xiaojing; Zheng, Ting; Zhang, Binyu; Lou, Xiaojie; Wang, Xiangjian

2014-02-19

Environment protection and human health concern is the driving force to eliminate the lead from commercial piezoelectric materials. In 2004, Saito et al. [ Saito et al., Nature , 2004 , 432 , 84 . ] developed an alkali niobate-based perovskite solid solution with a peak piezoelectric constant d33 of 416 pC/N when prepared in the textured polycrystalline form, intriguing the enthusiasm of developing high-performance lead-free piezoceramics. Although much attention has been paid on the alkali niobate-based system in the past ten years, no significant breakthrough in its d33 has yet been attained. Here, we report an alkali niobate-based lead-free piezoceramic with the largest d33 of ∼490 pC/N ever reported so far using conventional solid-state method. In addition, this material system also exhibits excellent integrated performance with d33∼390-490 pC/N and TC∼217-304 °C by optimizing the compositions. This giant d33 of the alkali niobate-based lead-free piezoceramics is ascribed to not only the construction of a new rhombohedral-tetragonal phase boundary but also enhanced dielectric and ferroelectric properties. Our finding may pave the way for "lead-free at last".

Highly Efficient and Scalable Compound Decomposition of Two-Electron Integral Tensor and Its Application in Coupled Cluster Calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, Bo; Kowalski, Karol

The representation and storage of two-electron integral tensors are vital in large- scale applications of accurate electronic structure methods. Low-rank representation and efficient storage strategy of integral tensors can significantly reduce the numerical overhead and consequently time-to-solution of these methods. In this paper, by combining pivoted incomplete Cholesky decomposition (CD) with a follow-up truncated singular vector decomposition (SVD), we develop a decomposition strategy to approximately represent the two-electron integral tensor in terms of low-rank vectors. A systematic benchmark test on a series of 1-D, 2-D, and 3-D carbon-hydrogen systems demonstrates high efficiency and scalability of the compound two-step decomposition ofmore » the two-electron integral tensor in our implementation. For the size of atomic basis set N_b ranging from ~ 100 up to ~ 2, 000, the observed numerical scaling of our implementation shows O(N_b^{2.5~3}) versus O(N_b^{3~4}) of single CD in most of other implementations. More importantly, this decomposition strategy can significantly reduce the storage requirement of the atomic-orbital (AO) two-electron integral tensor from O(N_b^4) to O(N_b^2 log_{10}(N_b)) with moderate decomposition thresholds. The accuracy tests have been performed using ground- and excited-state formulations of coupled- cluster formalism employing single and double excitations (CCSD) on several bench- mark systems including the C_{60} molecule described by nearly 1,400 basis functions. The results show that the decomposition thresholds can be generally set to 10^{-4} to 10^{-3} to give acceptable compromise between efficiency and accuracy.« less

Evaluation of a Pair-Wise Conflict Detection and Resolution Algorithm in a Multiple Aircraft Scenario

NASA Technical Reports Server (NTRS)

Carreno, Victor A.

2002-01-01

The KB3D algorithm is a pairwise conflict detection and resolution (CD&R) algorithm. It detects and generates trajectory vectoring for an aircraft which has been predicted to be in an airspace minima violation within a given look-ahead time. It has been proven, using mechanized theorem proving techniques, that for a pair of aircraft, KB3D produces at least one vectoring solution and that all solutions produced are correct. Although solutions produced by the algorithm are mathematically correct, they might not be physically executable by an aircraft or might not solve multiple aircraft conflicts. This paper describes a simple solution selection method which assesses all solutions generated by KB3D and determines the solution to be executed. The solution selection method and KB3D are evaluated using a simulation in which N aircraft fly in a free-flight environment and each aircraft in the simulation uses KB3D to maintain separation. Specifically, the solution selection method filters KB3D solutions which are procedurally undesirable or physically not executable and uses a predetermined criteria for selection.

Elastomeric Materials for Acoustical Applications

DTIC Science & Technology

1989-09-15

pfa UAtuWt.1. for Ado.iuatal Applvaations 828, 28n. •uaring Outdo t ho014 )I"PonL 1notoHMora, 6 U, I, 1. o4ront. dJo fmourg A Oo., |mtbaomer hmiaogyD...34Permeation, Diffusion, and Sorption of Gases and Vapors," in Methods of Experimental Phycics, 10 R. A. Fava, ed. (Academic Press, New York, 1981

Statistical measurement of the gamma-ray source-count distribution as a function of energy

NASA Astrophysics Data System (ADS)

Zechlin, H.-S.; Cuoco, A.; Donato, F.; Fornengo, N.; Regis, M.

2017-01-01

Photon counts statistics have recently been proven to provide a sensitive observable for characterizing gamma-ray source populations and for measuring the composition of the gamma-ray sky. In this work, we generalize the use of the standard 1-point probability distribution function (1pPDF) to decompose the high-latitude gamma-ray emission observed with Fermi-LAT into: (i) point-source contributions, (ii) the Galactic foreground contribution, and (iii) a diffuse isotropic background contribution. We analyze gamma-ray data in five adjacent energy bands between 1 and 171 GeV. We measure the source-count distribution dN/dS as a function of energy, and demonstrate that our results extend current measurements from source catalogs to the regime of so far undetected sources. Our method improves the sensitivity for resolving point-source populations by about one order of magnitude in flux. The dN/dS distribution as a function of flux is found to be compatible with a broken power law. We derive upper limits on further possible breaks as well as the angular power of unresolved sources. We discuss the composition of the gamma-ray sky and capabilities of the 1pPDF method.

The moduli space of vacua of $$ \\mathcal{N}=2 $$ class $$ \\mathcal{S} $$ theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Dan; Yonekura, Kazuya

We develop a systematic method to describe the moduli space of vacua of four dimensional N=2 class S theories including Coulomb branch, Higgs branch and mixed branches. In particular, we determine the Higgs and mixed branch roots, and the dimensions of the Coulomb and Higgs components of mixed branches. They are derived by using generalized Hitchin’s equations obtained from twisted compactification of 5d maximal Super-Yang-Mills, with local degrees of freedom at punctures given by (nilpotent) orbits. The crucial thing is the holomorphic factorization of the Seiberg-Witten curve and reduction of singularity at punctures. We illustrate our method by many examplesmore » including N=2 SQCD, T N theory and Argyres-Douglas theories.« less

Synchronous acquisition of multi-channel signals by single-channel ADC based on square wave modulation

NASA Astrophysics Data System (ADS)

Yi, Xiaoqing; Hao, Liling; Jiang, Fangfang; Xu, Lisheng; Song, Shaoxiu; Li, Gang; Lin, Ling

2017-08-01

Synchronous acquisition of multi-channel biopotential signals, such as electrocardiograph (ECG) and electroencephalograph, has vital significance in health care and clinical diagnosis. In this paper, we proposed a new method which is using single channel ADC to acquire multi-channel biopotential signals modulated by square waves synchronously. In this method, a specific modulate and demodulate method has been investigated without complex signal processing schemes. For each channel, the sampling rate would not decline with the increase of the number of signal channels. More specifically, the signal-to-noise ratio of each channel is n times of the time-division method or an improvement of 3.01 ×log2n dB, where n represents the number of the signal channels. A numerical simulation shows the feasibility and validity of this method. Besides, a newly developed 8-lead ECG based on the new method has been introduced. These experiments illustrate that the method is practicable and thus is potential for low-cost medical monitors.

Evaluation of N-ratio in selecting patients for adjuvant chemoradiotherapy after d2-gastrectomy.

PubMed

Costa Junior, Wilson Luiz da; Coimbra, Felipe José Fernández; Batista, Thales Paulo; Ribeiro, Héber Salvador de Castro; Diniz, Alessandro Landskron

2013-01-01

Whether adjuvant chemoradiotherapy may contribute to improve survival outcomes after D2-gastrectomy remains controversial. To explore the clinical utility of N-Ratio in selecting gastric cancer patients for adjuvant chemoradiotherapy after D2-gastrectomy. A retrospective cohort study was carried out on gastric cancer patients who underwent D2-gastrectomy alone or D2-gastrectomy plus adjuvant chemoradiotherapy (INT-0116 protocol) at the Hospital A. C. Camargo from September 1998 to December 2008. Statistical analysis were performed using multiple conventional methods, such as c-statistic, adjusted Cox's regression and stratified survival analysis. Our analysis involved 128 patients. According to c-statistic, the N-Ratio (i.e., as a continuous variable) presented "area under ROC curve" (AUC) of 0.713, while the number of metastatic nodes presented AUC of 0.705. After categorization, the cut-offs provide by Marchet et al. displayed the highest discriminating power - AUC value of 0.702. This N-Ratio categorization was confirmed as an independent predictor of survival using multivariate analyses. There also was a trend of better survival by adding of adjuvant chemoradiotherapy only for patients with milder degrees of lymphatic spread - 5-year survival of 23.1% vs 66.9%, respectively (HR = 0.426, 95% CI 0.150-1.202; P = 0.092). This study confirms the N-Ratio as a tool to improve the lymph node metastasis staging in gastric cancer and suggests the cut-offs provided by Marchet et al. as the best way for its categorization after a D2-gastrectomy. In these settings, the N-Ratio appears a useful tool to select patients for adjuvant chemoradiotherapy, and the benefit of adding this type of adjuvancy to D2-gastrectomy is suggested to be limited to patients with milder degrees of lymphatic spread (i.e., NR2, 10%-25%).

Enrichment of neonicotinoid insecticides from lemon juice sample with magnetic three-dimensional graphene as the adsorbent followed by determination with high-performance liquid chromatography.

PubMed

Liu, Li; Feng, Tao; Wang, Chun; Wu, Qiuhua; Wang, Zhi

2014-06-01

A novel 3D-graphene (3D-G) magnetic nanomaterial was prepared and used as an adsorbent for the extraction of four neonicotinoid insecticides (acetamiprid, imidacloprid, thiacloprid, and thiamethoxam) from lemon juice sample. Then, HPLC with UV detection was applied for the determination of the neonicotinoid insecticides desorbed from the 3D-G magnetic nanomaterial. The main experimental parameters that affect the extraction efficiencies such as the amount of 3D-G magnetic nanomaterial, sample solution pH, extraction time, salting-out effect, and desorption conditions were studied and optimized. As a result, the linear concentration range of the method was from 0.3 to 100.0 ng/mL for thiacloprid, from 0.5 to 100.0 ng/mL for imidacloprid and acetamiprid, and from 1.0 to 100.0 ng/mL for thiamethoxam, with correlation coefficients of 0.9965-0.9985, respectively. The LODs of the method based on an S/N of 3 were between 0.08 and 0.2 ng/mL. The enrichment factors obtained were between 67 and 427, and the RSDs (n = 6) were in the range from 4.6 to 7.1%, and the recoveries of the method fell in the range of 88.75 to 111.60%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chiral limit of N = 4 SYM and ABJM and integrable Feynman graphs

NASA Astrophysics Data System (ADS)

Caetano, João; Gürdoğan, Ömer; Kazakov, Vladimir

2018-03-01

We consider a special double scaling limit, recently introduced by two of the authors, combining weak coupling and large imaginary twist, for the γ-twisted N = 4 SYM theory. We also establish the analogous limit for ABJM theory. The resulting non-gauge chiral 4D and 3D theories of interacting scalars and fermions are integrable in the planar limit. In spite of the breakdown of conformality by double-trace interactions, most of the correlators for local operators of these theories are conformal, with non-trivial anomalous dimensions defined by specific, integrable Feynman diagrams. We discuss the details of this diagrammatics. We construct the doubly-scaled asymptotic Bethe ansatz (ABA) equations for multi-magnon states in these theories. Each entry of the mixing matrix of local conformal operators in the simplest of these theories — the bi-scalar model in 4D and tri-scalar model in 3D — is given by a single Feynman diagram at any given loop order. The related diagrams are in principle computable, up to a few scheme dependent constants, by integrability methods (quantum spectral curve or ABA). These constants should be fixed from direct computations of a few simplest graphs. This integrability-based method is advocated to be able to provide information about some high loop order graphs which are hardly computable by other known methods. We exemplify our approach with specific five-loop graphs.

Sensitivity and specificity of normality tests and consequences on reference interval accuracy at small sample size: a computer-simulation study.

PubMed

Le Boedec, Kevin

2016-12-01

According to international guidelines, parametric methods must be chosen for RI construction when the sample size is small and the distribution is Gaussian. However, normality tests may not be accurate at small sample size. The purpose of the study was to evaluate normality test performance to properly identify samples extracted from a Gaussian population at small sample sizes, and assess the consequences on RI accuracy of applying parametric methods to samples that falsely identified the parent population as Gaussian. Samples of n = 60 and n = 30 values were randomly selected 100 times from simulated Gaussian, lognormal, and asymmetric populations of 10,000 values. The sensitivity and specificity of 4 normality tests were compared. Reference intervals were calculated using 6 different statistical methods from samples that falsely identified the parent population as Gaussian, and their accuracy was compared. Shapiro-Wilk and D'Agostino-Pearson tests were the best performing normality tests. However, their specificity was poor at sample size n = 30 (specificity for P < .05: .51 and .50, respectively). The best significance levels identified when n = 30 were 0.19 for Shapiro-Wilk test and 0.18 for D'Agostino-Pearson test. Using parametric methods on samples extracted from a lognormal population but falsely identified as Gaussian led to clinically relevant inaccuracies. At small sample size, normality tests may lead to erroneous use of parametric methods to build RI. Using nonparametric methods (or alternatively Box-Cox transformation) on all samples regardless of their distribution or adjusting, the significance level of normality tests depending on sample size would limit the risk of constructing inaccurate RI. © 2016 American Society for Veterinary Clinical Pathology.

A surrogate analyte method to determine D-serine in mouse brain using liquid chromatography-tandem mass spectrometry.

PubMed

Kinoshita, Kohnosuke; Jingu, Shigeji; Yamaguchi, Jun-ichi

2013-01-15

A bioanalytical method for determining endogenous d-serine levels in the mouse brain using a surrogate analyte and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. [2,3,3-(2)H]D-serine and [(15)N]D-serine were used as a surrogate analyte and an internal standard, respectively. The surrogate analyte was spiked into brain homogenate to yield calibration standards and quality control (QC) samples. Both endogenous and surrogate analytes were extracted using protein precipitation followed by solid phase extraction. Enantiomeric separation was achieved on a chiral crown ether column with an analysis time of only 6 min without any derivatization. The column eluent was introduced into an electrospray interface of a triple-quadrupole mass spectrometer. The calibration range was 1.00 to 300 nmol/g, and the method showed acceptable accuracy and precision at all QC concentration levels from a validation point of view. In addition, the brain d-serine levels of normal mice determined using this method were the same as those obtained by a standard addition method, which is time-consuming but is often used for the accurate measurement of endogenous substances. Thus, this surrogate analyte method should be applicable to the measurement of d-serine levels as a potential biomarker for monitoring certain effects of drug candidates on the central nervous system. Copyright © 2012 Elsevier Inc. All rights reserved.

Monitoring glucose, calcium, and magnesium levels in saliva as a non-invasive analysis by sequential injection multi-parametric determination.

PubMed

Machado, Ana; Maneiras, Rui; Bordalo, Adriano A; Mesquita, Raquel B R

2018-08-15

The use of saliva for diagnose and surveillance of systemic illnesses, and general health has been arousing great interest worldwide, emerging as a highly desirable goal in healthcare. The collection is non-invasive, stress-free, inexpensive, and simple representing a major asset. Glucose, calcium, and magnesium concentration are three major parameters evaluated in clinical context due to their essential role in a wide range of biochemical reactions, and consequently many health disorders. In this work, a spectrophotometric sequential injection method is described for the fast screening of glucose, calcium, and magnesium in saliva samples. The glucose determination reaction involves the oxidation of the aldehyde functional group present in glucose with simultaneous reduction of 3,5-dinitrosalicylic acid (DNS) to 3-amino, 5-nitrosalicylic acid under alkaline conditions, followed by the development of colour. The determination of both metals is based on their reaction with cresolphtalein complexone (CPC), and the interference of calcium in the magnesium determination minimized by ethylene glycol-bis[β-aminoethyl ether]-N,N,N',N'-tetraacetic acid (EGTA). The developed multi-parametric method enabled dynamic ranges of 50 - 300 mg/dL for glucose, 0.1 - 2 mg/dL for calcium, and 0.1 - 0.5 mg/dL for magnesium. Determination rates of 28, 60, 52 h -1 were achieved for glucose, calcium, and magnesium, respectively. Less than 300 µL of saliva is required for the multi-parametric determination due to saliva viscosity and inherent necessity of dilution prior to analysis. RSDs lower than 5% were obtained, and the results agreed with those obtained by reference methods, while recovery tests confirmed its accuracy. Copyright © 2018 Elsevier B.V. All rights reserved.

New alkamides from maca (Lepidium meyenii).

PubMed

Zhao, Jianping; Muhammad, Ilias; Dunbar, D Chuck; Mustafa, Jamal; Khan, Ikhlas A

2005-02-09

Maca (Lepidium meyenii) has been used as a food in Peru for thousands of years. More recently a wide array of commercial maca products have gained popularity as dietary supplements, with claims of anabolic and aphrodisiac effects, although the biologically active principles are not fully known. In an earlier chemical investigation, two new alkamides and a novel fatty acid, as well as the N-hydroxypyridine derivative, macaridine, were isolated from L. meyenii. Further examination has led to the isolation of five additional new alkamides, namely, N-benzyl-9-oxo-12Z-octadecenamide (1), N-benzyl-9-oxo-12Z,15Z-octadecadienamide (2), N-benzyl-13-oxo-9E,11E-octadecadienamide (3), N-benzyl-15Z-tetracosenamide (4), and N-(m-methoxybenzyl)hexadecanamide (5). Their structures were established by spectrometric and spectroscopic methods including ESI-HRMS, EI-MS, (1)H, (13)C, and 2D NMR, as well as (1)H-(15)N 2D HMBC experiments. In addition, the identity of N-benzyl-15Z-tetracosenamide (4) was confirmed by synthesis. These compounds have been found from only L. meyenii and could be used as markers for authentication and standardization.

Characterization of 3D joint space morphology using an electrostatic model (with application to osteoarthritis)

NASA Astrophysics Data System (ADS)

Cao, Qian; Thawait, Gaurav; Gang, Grace J.; Zbijewski, Wojciech; Reigel, Thomas; Brown, Tyler; Corner, Brian; Demehri, Shadpour; Siewerdsen, Jeffrey H.

2015-02-01

Joint space morphology can be indicative of the risk, presence, progression, and/or treatment response of disease or trauma. We describe a novel methodology of characterizing joint space morphology in high-resolution 3D images (e.g. cone-beam CT (CBCT)) using a model based on elementary electrostatics that overcomes a variety of basic limitations of existing 2D and 3D methods. The method models each surface of a joint as a conductor at fixed electrostatic potential and characterizes the intra-articular space in terms of the electric field lines resulting from the solution of Gauss’ Law and the Laplace equation. As a test case, the method was applied to discrimination of healthy and osteoarthritic subjects (N = 39) in 3D images of the knee acquired on an extremity CBCT system. The method demonstrated improved diagnostic performance (area under the receiver operating characteristic curve, AUC > 0.98) compared to simpler methods of quantitative measurement and qualitative image-based assessment by three expert musculoskeletal radiologists (AUC = 0.87, p-value = 0.007). The method is applicable to simple (e.g. the knee or elbow) or multi-axial joints (e.g. the wrist or ankle) and may provide a useful means of quantitatively assessing a variety of joint pathologies.

Blue-shifted and red-shifted hydrogen bonds: Theoretical study of the CH3CHO· · ·HNO complexes

NASA Astrophysics Data System (ADS)

Yang, Yong; Zhang, Weijun; Gao, Xiaoming

The blue-shifted and red-shifted H-bonds have been studied in complexes CH3CHO?HNO. At the MP2/6-31G(d), MP2/6-31+G(d,p) MP2/6-311++G(d,p), B3LYP/6-31G(d), B3LYP/6-31+G(d,p) and B3LYP/6-311++G(d,p) levels, the geometric structures and vibrational frequencies of complexes CH3CHO?HNO are calculated by both standard and CP-corrected methods, respectively. Complex A exhibits simultaneously red-shifted C bond H?O and blue-shifted N bond H?O H-bonds. Complex B possesses simultaneously two blue-shifted H-bonds: C bond H?O and N bond H?O. From NBO analysis, it becomes evident that the red-shifted C bond H?O H-bond can be explained on the basis of the two opposite effects: hyperconjugation and rehybridization. The blue-shifted C bond H?O H-bond is a result of conjunct C bond H bond strengthening effects of the hyperconjugation and the rehybridization due to existence of the significant electron density redistribution effect. For the blue-shifted N bond H?O H-bonds, the hyperconjugation is inhibited due to existence of the electron density redistribution effect. The large blue shift of the N bond H stretching frequency is observed because the rehybridization dominates the hyperconjugation.

The Accuracy of Conventional 2D Video for Quantifying Upper Limb Kinematics in Repetitive Motion Occupational Tasks

PubMed Central

Chen, Chia-Hsiung; Azari, David; Hu, Yu Hen; Lindstrom, Mary J.; Thelen, Darryl; Yen, Thomas Y.; Radwin, Robert G.

2015-01-01

Objective Marker-less 2D video tracking was studied as a practical means to measure upper limb kinematics for ergonomics evaluations. Background Hand activity level (HAL) can be estimated from speed and duty cycle. Accuracy was measured using a cross correlation template-matching algorithm for tracking a region of interest on the upper extremities. Methods Ten participants performed a paced load transfer task while varying HAL (2, 4, and 5) and load (2.2 N, 8.9 N and 17.8 N). Speed and acceleration measured from 2D video were compared against ground truth measurements using 3D infrared motion capture. Results The median absolute difference between 2D video and 3D motion capture was 86.5 mm/s for speed, and 591 mm/s2 for acceleration, and less than 93 mm/s for speed and 656 mm/s2 for acceleration when camera pan and tilt were within ±30 degrees. Conclusion Single-camera 2D video had sufficient accuracy (< 100 mm/s) for evaluating HAL. Practitioner Summary This study demonstrated that 2D video tracking had sufficient accuracy to measure HAL for ascertaining the American Conference of Government Industrial Hygienists Threshold Limit Value® for repetitive motion when the camera is located within ±30 degrees off the plane of motion when compared against 3D motion capture for a simulated repetitive motion task. PMID:25978764

Clinical application of a 3D-printed scaffold in chronic wound treatment: a case series.

PubMed

Sun, Haining; Lv, Huayao; Qiu, Fanghui; Sun, Duolun; Gao, Yue; Chen, Ning; Zheng, YongKe; Deng, Kunxue; Yang, Yaya; Zhang, Haitao; Xu, Tao; Ren, Dongni

2018-05-02

This case series evaluates the safety and effectiveness of 3D-printed scaffold in chronic wounds. The scaffold is a composite of natural and synthetic materials, and can be prepared in the form of powder or membrane. We recruited patients with pressure ulcera (PU) and/or a diabetic foot ulcers (DFU). We used two methods: 3D-printed scaffolds alone, or 3D-printing powder mixed with platelet-rich fibrinogen (PRF). Clinicians and patients were asked to rate the scaffold's ease of application and comfort during use. A total of five patients were recruited; four with a PU and one with a DFU. For the patient treated with the 3D-printed scaffold membrane (n=1), their PU healed in 28 days, and for patients treated with the 3D-printed scaffold powder (n=2), their PUs healed in 54 days. For the patients treated with the 3D-printing powder mixed with PRF (n=2), the patient with a PU healed in 11 days, and the patient with the DFU healed in 14 days. All clinicians rated the 3D-printed scaffold as 'easy' or 'very easy' to use, and patients rated their comfort during wear and at dressing change as 'good' or 'very good'. This study demonstrated that 3D-printed scaffold was convenient to use, have the potential to improve wound healing rates, and provided a safe and effective way for treating chronic wounds.

[Chemical constituents contained in seeds of Notopterygium franchetii].

PubMed

Zhang, Yanxia; Jiang, Shunyuan; Xu, Kaijie; Shi, Haili; Zhou, Yi; Deng, Wenlong; Ding, Lisheng; Peng, Shulin

2012-04-01

To study the chemical constituents from the seeds of Notopterygium franchetii. Ethanol extracts of seeds N. franchetii were separated and purified by such methods as normal and reversed phase column chromatographies and thin-layer chromatography and structurally elucidated by MS and NMR evidences. Twenty nine compounds were separated, they were isoimperatorin (1), [3-sitosterol (2), phellopterin (3), bergapten (4), N-tetra, hexa, octacosanoylanthranilic acid (5-7), daucosterol (8), oxypeucedanin hydrate (9), umbelliferone (10), demethylfuropinnarin (11), (2S, 3S, 4R, 8E)-2-[(2'R)- 2'-hydroxydoco, trico, tetraco, entaco, hexaco sanosylamino] -octadecene-1, 3, 4-triol (12-16), (-)-oxypeucedanin (17), diosmetin (18), bergaptol-O-beta-D-glucopyranoside (19), nodakenin (20), 1'-O-beta-D-glucopyranosyl-(2R, 3S)-3-hydroxynodakenetin (21), uracil (22), decuroside V (23), 8-O-beta-D-glucopyranosyl-5-hydroxypsoralen (24), 8-O-beta-D-glucopyranosyl-5-methoxylpsoralen (25), diosmin (26), alaschanioside C (27), kynurenic acid (28) and mannitol (29). All of these compounds were separated from the seeds of N. franchetii for the first time. Of them, 18, 22, 26 and 29 were firstly obtained from genus Notopterygium.

Chemical Welding on Semimetallic TiS2 Nanosheets for High-Performance Flexible n-Type Thermoelectric Films.

PubMed

Zhou, Yuan; Wan, Juanyong; Li, Qi; Chen, Lei; Zhou, Jiyang; Wang, Heao; He, Dunren; Li, Xiaorui; Yang, Yaocheng; Huang, Huihui

2017-12-13

Solution-based processing of two-dimensional (2D) materials provides the possibility of allowing these materials to be incorporated into large-area thin films, which can translate the interesting fundamental properties of 2D materials into available devices. Here, we report for the first time a novel chemical-welding method to achieve high-performance flexible n-type thermoelectric films using 2D semimetallic TiS 2 nanosheets. We employ chemically exfoliated TiS 2 nanosheets bridged with multivalent cationic metal Al 3+ to cross-link the nearby sheets during the film deposition process. We find that such a treatment can greatly enhance the stability of the film and can improve the power factor by simultaneously increasing the Seebeck coefficient and electrical conductivity. The resulting TiS 2 nanosheet-based flexible film shows a room temperature power factor of ∼216.7 μW m -1 K -2 , which is among the highest chemically exfoliated 2D transition-metal dichalcogenide nanosheet-based films and comparable to the best flexible n-type thermoelectric films, to our knowledge, indicating its potential applications in wearable electronics.

The Origins of Specificity in the Microcin-Processing Protease TldD/E.

PubMed

Ghilarov, Dmitry; Serebryakova, Marina; Stevenson, Clare E M; Hearnshaw, Stephen J; Volkov, Dmitry S; Maxwell, Anthony; Lawson, David M; Severinov, Konstantin

2017-10-03

TldD and TldE proteins are involved in the biosynthesis of microcin B17 (MccB17), an Escherichia coli thiazole/oxazole-modified peptide toxin targeting DNA gyrase. Using a combination of biochemical and crystallographic methods we show that E. coli TldD and TldE interact to form a heterodimeric metalloprotease. TldD/E cleaves the N-terminal leader sequence from the modified MccB17 precursor peptide, to yield mature antibiotic, while it has no effect on the unmodified peptide. Both proteins are essential for the activity; however, only the TldD subunit forms a novel metal-containing active site within the hollow core of the heterodimer. Peptide substrates are bound in a sequence-independent manner through β sheet interactions with TldD and are likely cleaved via a thermolysin-type mechanism. We suggest that TldD/E acts as a "molecular pencil sharpener": unfolded polypeptides are fed through a narrow channel into the active site and processively truncated through the cleavage of short peptides from the N-terminal end. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Indian Ocean Validation,

DTIC Science & Technology

1987-09-01

S9 fd 30 2 D0i 0m10 20 802 AR. Oy ad n A o io in 3 0 3 7 ..n . . . w o w., , ... .. . . . . d ata m gaterng eie ws amdfe Lito sT-1 Omeg nav~igtion AE...signals propagated from each of N stations over paths of 2-10 length dl, d2, ... as shown in Figure 2.1. Station 2 Station N Station 1 D dl SUBJECT Figure...t2* = (d1* - d2*)/c + ( El - 62) t2* - t3* = (d2* - d3*)/c + ( E2 - E3) t*N 1 - t*N - ( d *N 1 - dN*)/c + ( N-1 EN) (6) 47he results obtained in

Computational predictions of stereochemistry in asymmetric thiazolium- and triazolium-catalyzed benzoin condensations.

PubMed

Dudding, Travis; Houk, Kendall N

2004-04-20

The catalytic asymmetric thiazolium- and triazolium-catalyzed benzoin condensations of aldehydes and ketones were studied with computational methods. Transition-state geometries were optimized by using Morokuma's IMOMO [integrated MO (molecular orbital) + MO method] variation of ONIOM (n-layered integrated molecular orbital method) with a combination of B3LYP/6-31G(d) and AM1 levels of theory, and final transition-state energies were computed with single-point B3LYP/6-31G(d) calculations. Correlations between experiment and theory were found, and the origins of stereoselection were identified. Thiazolium catalysts were predicted to be less selective then triazolium catalysts, a trend also found experimentally.

Ruthenium(II) piano stool coordination compounds with aminomethylphosphanes: Synthesis, characterisation and preliminary biological study in vitro.

PubMed

Płotek, Michał; Starosta, Radosław; Komarnicka, Urszula K; Skórska-Stania, Agnieszka; Kołoczek, Przemysław; Kyzioł, Agnieszka

2017-05-01

Reaction of {[Ru(η 6 -p-cymene)Cl] 2 (μ-Cl) 2 } (1) with aminomethylphosphane derived from morpholine (P{CH 2 N(CH 2 CH 2 ) 2 O} 3 (A), PPh 2 {CH 2 N(CH 2 CH 2 ) 2 O} (B)) or piperazine (P{CH 2 N(CH 2 CH 2 ) 2 NCH 2 CH 3 } 3 (C), PPh 2 {CH 2 N(CH 2 CH 2 ) 2 NCH 2 CH 3 } (D)) results in four new piano stool ruthenium(II) coordination compounds: [Ru(η 6 -p-cymene)Cl 2 (A)] (2A), [Ru(η 6 -p-cymene)Cl 2 (B)] (2B), [Ru(η 6 -p-cymene)Cl 2 (C)] (2C) and [Ru(η 6 -p-cymene)Cl 2 (D)] (2D). Every complex was fully characterized using spectroscopic methods ( 1 H, 13 C{ 1 H}, 31 P{ 1 H} NMR and ESI-MS), elemental analysis, X-ray single crystal diffraction and DFT calculations. Preliminary studies of in vitro cytotoxicity on the A549 (human lung adenocarcinoma) and MCF7 (human breast adenocarcinoma) cell lines revealed 2A-2D activity in the same order of magnitude as in the case of cisplatin. Additionally, the study confirmed the ability of 2A-2D to interact with DNA helix and transferrin. Copyright © 2017 Elsevier Inc. All rights reserved.

Deuterium isotope effects on 13C and 15N chemical shifts of intramolecularly hydrogen-bonded enaminocarbonyl derivatives of Meldrum’s and Tetronic acid

NASA Astrophysics Data System (ADS)

Ullah, Saif; Zhang, Wei; Hansen, Poul Erik

2010-07-01

Secondary deuterium isotope effects on 13C and 15N nuclear shieldings in a series of cyclic enamino-diesters and enamino-esters and acyclic enaminones and enamino-esters have been examined and analysed using NMR and DFT (B3LYP/6-31G(d,p)) methods. One-dimensional and two-dimensional NMR spectra of enaminocarbonyl and their deuterated analogues were recorded in CDCl 3 and CD 2Cl 2 at variable temperatures and assigned. 1JNH coupling constants for the derivatives of Meldrum's and tetronic acids reveal that they exist at the NH-form. It was demonstrated that deuterium isotope effects, for the hydrogen bonded compounds, due to the deuterium substitution at the nitrogen nucleus lead to large one-bond isotope effects at nitrogen, 1Δ 15N(D), and two-bond isotope effects on carbon nuclei, 2ΔC(ND), respectively. A linear correlations exist between 2ΔC(ND) and 1Δ 15N(D) whereas the correlation with δNH is divided into two. A good agreement between the experimentally observed 2ΔC(ND) and calculated dσ 13C/dR NH was obtained. A very good correlation between calculated NH bond lengths and observed NH chemical shifts is found. The observed isotope effects are shown to depend strongly on Resonance Assisted Hydrogen bonding.

Evaluation of Delamination Onset and Growth Characterization Methods under Mode I Fatigue Loading

NASA Technical Reports Server (NTRS)

Murri, Gretchen B.

2013-01-01

Double-cantilevered beam specimens of IM7/8552 graphite/epoxy from two different manufacturers were tested in static and fatigue to compare the material characterization data and to evaluate a proposed ASTM standard for generating Paris Law equations for delamination growth. Static results were used to generate compliance calibration constants for reducing the fatigue data, and a delamination resistance curve, GIR, for each material. Specimens were tested in fatigue at different initial cyclic GImax levels to determine a delamination onset curve and the delamination growth rate. The delamination onset curve equations were similar for the two sources. Delamination growth rate was calculated by plotting da/dN versus GImax on a log-log scale and fitting a Paris Law. Two different data reduction methods were used to calculate da/dN. To determine the effects of fiber-bridging, growth results were normalized by the delamination resistance curves. Paris Law exponents decreased by 31% to 37% after normalizing the data. Visual data records from the fatigue tests were used to calculate individual compliance constants from the fatigue data. The resulting da/dN versus GImax plots showed improved repeatability for each source, compared to using averaged static data. The Paris Law expressions for the two sources showed the closest agreement using the individually fit compliance data.

On exact correlation functions of chiral ring operators in 2 d N=(2, 2) SCFTs via localization

NASA Astrophysics Data System (ADS)

Chen, Jin

2018-03-01

We study the extremal correlation functions of (twisted) chiral ring operators via superlocalization in N=(2, 2) superconformal field theories (SCFTs) with central charge c ≥ 3, especially for SCFTs with Calabi-Yau geometric phases. We extend the method in arXiv: 1602.05971 with mild modifications, so that it is applicable to disentangle operators mixing on S 2 in nilpotent (twisted) chiral rings of 2 d SCFTs. With the extended algorithm and technique of localization, we compute exactly the extremal correlators in 2 d N=(2, 2) (twisted) chiral rings as non-holomorphic functions of marginal parameters of the theories. Especially in the context of Calabi-Yau geometries, we give an explicit geometric interpretation to our algorithm as the Griffiths transversality with projection on the Hodge bundle over Calabi-Yau complex moduli. We also apply the method to compute extremal correlators in Kähler moduli, or say twisted chiral rings, of several interesting Calabi-Yau manifolds. In the case of complete intersections in toric varieties, we provide an alternative formalism for extremal correlators via localization onto Higgs branch. In addition, as a spinoff we find that, from the extremal correlators of the top element in twisted chiral rings, one can extract chiral correlators in A-twisted topological theories.

Vector matter waves in two-component Bose-Einstein condensates with spatially modulated nonlinearities

NASA Astrophysics Data System (ADS)

Xu, Si-Liu; He, Jun-Rong; Xue, Li; Belić, Milivoj R.

2018-02-01

We demonstrate three-dimensional (3D) vector solitary waves in the coupled (3 + 1)-D nonlinear Gross-Pitaevskii equations with variable nonlinearity coefficients. The analysis is carried out in spherical coordinates, providing novel localized solutions that depend on three modal numbers, l, m, and n. Using the similarity transformation (ST) method in 3D, vector solitary waves are built with the help of a combination of harmonic and trapping potentials, including multipole solutions and necklace rings. In general, the solutions found are stable for low values of the modal numbers; for values larger than 2, the solutions are found to be unstable. Variable nonlinearity allows the utilization of soliton management methods.

Solvent induced synthesis, structure and properties of coordination polymers based on 5-hydroxyisophthalic acid as linker and 1,10-phenanthroline as auxiliary ligand

NASA Astrophysics Data System (ADS)

Kariem, Mukaddus; Yawer, Mohd; Sheikh, Haq Nawaz

2015-11-01

Three new coordination polymers [Mn(hip)(phen) (H2O)]n (1), [Co(hip)(phen) (H2O)]n (2), and [Cd(hip) (phen) (H2O)]n (3) (H2hip=5-hydroxyisophthalic acid; phen=1,10-phenanthroline) have been synthesized by solvo-hydrothermal method using diethyl formamide-water (DEF-H2O) as solvent system. Single-crystal X-ray diffraction analysis reveals that all three coordination polymers 1, 2 and 3 crystallize in monoclinic space group P2/n. Metal ions are inter-connected by hydroxyisophthalate anions forming zig-zag 1D chain. 1D chains are further inter-connected by hydrogen bonding and π-π stacking interactions leading to 3D supramolecular architecture. Hydrogen-bonding and π-π stacking provide thermal stability to polymers. Compounds 1 and 2 are paramagnetic at room temperature and variable temperature magnetic moment measurements revealed weak ferromagnetic interactions between metal ions at low temperature. Compound 3 exhibits excellent photoluminescence with large Stokes shift.

Liquid chromatographic determination of benzocaine and N-acetylbenzocaine in the edible fillet tissue from rainbow trout

USGS Publications Warehouse

Meinertz, J.R.; Stehly, G.R.; Hubert, T.D.; Bernardy, J.A.

1999-01-01

A method was developed for determining benzocaine and N-acetylbenzocaine concentrations in fillet tissue of rainbow trout. The method involves extracting the analytes with acetonitrile, removing lipids or hydrophobic compounds from the extract with hexane, and providing additional clean-up with solid-phase extraction techniques. Analyte concentrations are determined using reversed-phase high-performance liquid chromatographic techniques with an isocratic mobile phase and UV detection. The accuracy (range, 92 to 121%), precision (R.S.D., <14%), and sensitivity (method quantitation limit, <24 ng/g) for each analyte indicate the usefulness of this method for studies characterizing the depletion of benzocaine residues from fish exposed to benzocaine. Copyright (C) 1999.

Production of unnaturally linked chimeric proteins using a combination of sortase-catalyzed transpeptidation and click chemistry.

PubMed

Witte, Martin D; Theile, Christopher S; Wu, Tongfei; Guimaraes, Carla P; Blom, Annet E M; Ploegh, Hidde L

2013-09-01

Chimeric proteins, including bispecific antibodies, are biological tools with therapeutic applications. Genetic fusion and ligation methods allow the creation of N-to-C and C-to-N fused recombinant proteins, but not unnaturally linked N-to-N and C-to-C fusion proteins. This protocol describes a simple procedure for the production of such chimeric proteins, starting from correctly folded proteins and readily available peptides. By equipping the N terminus or C terminus of the proteins of interest with a set of click handles using sortase A, followed by a strain-promoted click reaction, unnatural N-to-N and C-to-C linked (hetero) fusion proteins are established. Examples of proteins that have been conjugated via this method include interleukin-2, interferon-α, ubiquitin, antibodies and several single-domain antibodies. If the peptides, sortase A and the proteins of interest are in hand, the unnaturally N-to-N and C-to-C fused proteins can be obtained in 3-4 d.

The price of privately releasing contingency tables, and the spectra of random matrices with correlated rows

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasiviswanathan, Shiva; Rudelson, Mark; Smith, Adam

2009-01-01

Contingency tables are the method of choice of government agencies for releasing statistical summaries of categorical data. In this paper, we consider lower bounds on how much distortion (noise) is necessary in these tables to provide privacy guarantees when the data being summarized is sensitive. We extend a line of recent work on lower bounds on noise for private data analysis [10, 13. 14, 15] to a natural and important class of functionalities. Our investigation also leads to new results on the spectra of random matrices with correlated rows. Consider a database D consisting of n rows (one per individual),more » each row comprising d binary attributes. For any subset of T attributes of size |T| = k, the marginal table for T has 2{sup k} entries; each entry counts how many times in the database a particular setting of these attributes occurs. Imagine an agency that wishes to release all (d/k) contingency tables for a given database. For constant k, previous work showed that distortion {tilde {Omicron}}(min{l_brace}n, (n{sup 2}d){sup 1/3}, {radical}d{sup k}{r_brace}) is sufficient for satisfying differential privacy, a rigorous definition of privacy that has received extensive recent study. Our main contributions are: (1) For {epsilon}- and ({epsilon}, {delta})-differential privacy (with {epsilon} constant and {delta} = 1/poly(n)), we give a lower bound of {tilde {Omega}}(min{l_brace}{radical}n, {radical}d{sup k}{r_brace}), which is tight for n = {tilde {Omega}}(d{sup k}). Moreover, for a natural and popular class of mechanisms based on additive noise, our bound can be strengthened to {Omega}({radical}d{sup k}), which is tight for all n. Our bounds extend even to non-constant k, losing roughly a factor of {radical}2{sup k} compared to the best known upper bounds for large n. (2) We give efficient polynomial time attacks which allow an adversary to reconstruct sensitive infonnation given insufficiently perturbed contingency table releases. For constant k, we obtain a lower bound of {tilde {Omega}}(min{l_brace}{radical}n, {radical}d{sup k}{r_brace}) that applies to a large class of privacy notions, including K-anonymity (along with its variants) and differential privacy. In contrast to our bounds for differential privacy, this bound (a) is shown only for constant k, but (b) is tight for all values of n when k is constant. (3) Our reconstruction-based attacks require a new lower bound on the least singular values of random matrices with correlated rows. For a constant k, consider a matrix M with (d/k) rows which are formed by taking all possible k-way entry-wise products of an underlying set of d random vectors. We show that even for nearly square matrices with d{sup k}/log d columns, the least singular value is {Omega}({radical}d{sup k}) with high probability - asymptotically, the same bound as one gets for a matrix with independent rows. The proof requires several new ideas for analyzing random matrices and could be of independent interest.« less

Bioconcentration of (15)N-tamoxifen at environmental concentration in liver, gonad and muscle of Danio rerio.

PubMed

Orias, Frédéric; Simon, Laurent; Mialdea, Gladys; Clair, Angéline; Brosselin, Vanessa; Perrodin, Yves

2015-10-01

Pharmaceutical compounds (PCs) are ubiquitous in aquatic ecosystems. In addition to the direct ecotoxicological risk presented by certain PCs, others can accumulate inside organisms and along trophic webs, subsequently contaminating whole ecosystems. We studied the bioconcentration of a bioaccumulative PC already found several times in the environment: tamoxifen. To this end, we exposed Danio rerio for 21d to (15)N-tamoxifen concentrations ranging from 0.1 to 10µg/L and used an analytic method based on stable isotopes to evaluate the tamoxifen content in these organisms. The evolution of the (15)N/(14)N ratio was thus measured in liver, muscle and gonads of exposed fish compared to control fish. We succeeded in quantifying (15)N-tamoxifen bioconcentrations at all the exposure concentrations tested. The highest bioconcentration factors of tamoxifen measured were 14,920 in muscle, 73,800 in liver and 85,600 in gonads of fish after 21d exposure at a nominal concentration of 10µg/L. However, these bioconcentration factors have to be considered as maximal values (BCFMAX). Indeed, despite its proven stability, tamoxifen can be potentially partially degraded during experiments. We now need to refine these results by using a direct analytic method (i.e. LC-MS/MS). Copyright © 2015 Elsevier Inc. All rights reserved.

Design of a new controller to treat the obstructive sleep apnea

NASA Astrophysics Data System (ADS)

Netzel, Thomas

2002-06-01

The obstructive sleep apnoea (OSA) is a sleep related breathing disorder caused by a relaxation of the upper airway structure during the sleep that leads to a complete closure of the upper airway. The most successful therapy is the nasal continuous positive airway pressure (nCPAP) treatment that keeps the airway opened. More recent devices use an automatic adaptation of the applied pressure. Either the forced oscillation technique (FOT) or the evaluation of the inspiration flow contour are used to evaluate the severity of obstructions. Both methods have disadvantages that may lead to wrong applied pressures. Based on the precise measurement of airflow and mask pressure during nCPAP with a Weinmann SOMNOsmart and additional polysomnography a new parameter set is presented that uses the advantage of both methods to detect the obstructive sleep apnoea. To evaluate the applicability of this parameter set to control Auto-nCPAP-devices a fuzzy-controller is designed under MATLAB/Simulink using an A/D-D/A-converter to control the blower of the SOMNOsmart during Auto-nCPAP-therapy. Obstructive events are detected and treated with a rise of nCPAP-pressure depending on the inspiratory flow requirement. The pressure is lowered after the end of flow limited phases. Although temporary low pressures no oxygen desaturation is recognized by the pulse oxymeter.

Changes in transcriptional orientation are associated with increases in evolutionary rates of enterobacterial genes

PubMed Central

2011-01-01

Background Changes in transcriptional orientation (“CTOs”) occur frequently in prokaryotic genomes. Such changes usually result from genomic inversions, which may cause a conflict between the directions of replication and transcription and an increase in mutation rate. However, CTOs do not always lead to the replication-transcription confrontation. Furthermore, CTOs may cause deleterious disruptions of operon structure and/or gene regulations. The currently existing CTOs may indicate relaxation of selection pressure. Therefore, it is of interest to investigate whether CTOs have an independent effect on the evolutionary rates of the affected genes, and whether these genes are subject to any type of selection pressure in prokaryotes. Methods Three closely related enterbacteria, Escherichia coli, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium, were selected for comparisons of synonymous (dS) and nonsynonymous (dN) substitution rate between the genes that have experienced changes in transcriptional orientation (changed-orientation genes, “COGs”) and those that do not (same-orientation genes, “SOGs”). The dN/dS ratio was also derived to evaluate the selection pressure on the analyzed genes. Confounding factors in the estimation of evolutionary rates, such as gene essentiality, gene expression level, replication-transcription confrontation, and decreased dS at gene terminals were controlled in the COG-SOG comparisons. Results We demonstrate that COGs have significantly higher dN and dS than SOGs when a series of confounding factors are controlled. However, the dN/dS ratios are similar between the two gene groups, suggesting that the increase in dS can sufficiently explain the increase in dN in COGs. Therefore, the increases in evolutionary rates in COGs may be mainly mutation-driven. Conclusions Here we show that CTOs can increase the evolutionary rates of the affected genes. This effect is independent of the replication-transcription confrontation, which is suggested to be the major cause of inversion-associated evolutionary rate increases. The real cause of such evolutionary rate increases remains unclear but is worth further explorations. PMID:22152004

Pharmacokinetics of sarizotan after oral administration of single and repeat doses in healthy subjects.

PubMed

Krösser, S; Tillner, J; Fluck, M; Ungethüm, W; Wolna, P; Kovar, A

2007-05-01

Sarizotan is a 5-HTIA receptor agonist with high affinity for D3 and D4 receptors. Here we report the pharmacokinetic and tolerability results from four Phase 1 studies. Two single-dose (5 -25 mg, n = 25, 0.5 - 5 mg, n = 16) and two multiple-dose (10 and 20 mg b.i.d., n = 30, 5 mg b.i.d., n = 12) studies with orally administered sarizotan HCl were carried out in healthy subjects. Plasma sarizotan HCl concentrations were measured using a validated HPLC method and fluorescence or MS/MS detection. Pharmacokinetic parameters were obtained using standard non-compartmental methods. Sarizotan was rapidly absorbed, group-median times to reach maximum concentration (tmax) ranged from 0.5 -2.25 h after single doses and during steady state. Maximum plasma concentration (Cmax) and tmax were slightly dependent on formulation and food intake, whereas area under the curve (AUC) was unaffected by these factors. AUC and Cmax increased dose-proportionally over the tested dose range. Independently of dose and time, sarizotan HCl plasma concentrations declined polyexponentially with a terminal elimination half-life (t1/2) of 5 - 7 h. Accumulation factors corresponded to t1/2 values, and steady state was reached within 24 h. Plasma metabolite concentrations were considerably lower than those of the parent drug. The ratio metabolite AUC : parent drug AUC was time- and dose-independent for all three metabolites suggesting that the metabolism of sarizotan is non-saturable in the tested dose range. The pharmacokinetics of sarizotan were dose-proportional and time-independent for the dose range 0.5 -25 mg). The drug was well-tolerated by healthy subjects up to a single dose of 20 mg.