A simple method of obtaining concentration depth-profiles from X-ray diffraction
NASA Technical Reports Server (NTRS)
Wiedemann, K. E.; Unnam, J.
1984-01-01
The construction of composition profiles from X-ray intensity bands was investigated. The intensity band-to-composition profile transformation utilizes a solution which can be easily evaluated. The technique can be applied to thin films and thick speciments for which the variation of lattice parameters, linear absorption coefficient, and reflectivity with composition are known. A deconvolution scheme with corrections for the instrumental broadening and ak-alfadoublet is discussed.
Fatigue crack growth in unidirectional metal matrix composite
NASA Technical Reports Server (NTRS)
Ghosn, Louis J.; Telesman, Jack; Kantzos, Peter
1990-01-01
The weight function method was used to determine the effective stress intensity factor and the crack opening profile for a fatigue tested composite which exhibited fiber bridging. The bridging mechanism was modeled using two approaches; the crack closure approach and the shear lag approach. The numerically determined stress intensity factor values from both methods were compared and correlated with the experimentally obtained crack growth rates for SiC/Ti-15-3 (0)(sub 8) oriented composites. The near crack tip opening profile was also determined for both methods and compared with the experimentally obtained measurements.
NASA Astrophysics Data System (ADS)
Ryashin, N. S.; Malikov, A. G.; Shikalov, V. S.; Gulyaev, I. P.; Kuchumov, B. M.; Klinkov, S. V.; Kosarev, V. F.; Orishich, A. M.
2017-10-01
The paper presents results of the cold spraying of aluminum bronze coatings on substrates profiled with WC/Ni tracks obtained by laser cladding. Reinforcing cermet frames shaped as grids with varied mesh sizes were clad on stainless steel substrates using a CO2 laser machine "Siberia" (ITAM SB RAS, Russia). As a result, surfaces/substrates with heterogeneous shape, composition, and mechanical properties were obtained. Aluminum bronze coatings were deposited from 5lF-NS powder (Oerlikon Metco, Switzerland) on those substrates using cold spraying equipment (ITAM SB RAS). Data of profiling, microstructure diagnostics, EDS analysis, and mechanical tests of obtained composites is reported. Surface relief of the sprayed coatings dependence on substrate structure has been demonstrated.
Spatial Evolution of the Thickness Variations over a CFRP Laminated Structure
NASA Astrophysics Data System (ADS)
Davila, Yves; Crouzeix, Laurent; Douchin, Bernard; Collombet, Francis; Grunevald, Yves-Henri
2017-10-01
Ply thickness is one of the main drivers of the structural performance of a composite part. For stress analysis calculations (e.g., finite element analysis), composite plies are commonly considered to have a constant thickness compared to the reality (coefficients of variation up to 9% of the mean ply thickness). Unless this variability is taken into account reliable property predictions cannot be made. A modelling approach of such variations is proposed using parameters obtained from a 16-ply quasi-isotropic CFRP plate cured in an autoclave. A discrete Fourier transform algorithm is used to analyse the frequency response of the observed ply and plate thickness profiles. The model inputs, obtained by a mathematical representation of the ply thickness profiles, permit the generation of a representative stratification considering the spatial continuity of the thickness variations that are in good agreement with the real ply profiles spread over the composite part. A residual deformation FE model of the composite plate is used to illustrate the feasibility of the approach.
NASA Astrophysics Data System (ADS)
Mohajernia, Shiva; Mazare, Anca; Hwang, Imgon; Gaiaschi, Sofia; Chapon, Patrick; Hildebrand, Helga; Schmuki, Patrik
2018-06-01
In this work we study the depth composition of anodic TiO2 nanotube layers. We use elemental depth profiling with Glow Discharge Optical Emission Spectroscopy and calibrate the results of this technique with X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS). We establish optimized sputtering conditions for nanotubular structures using the pulsed RF mode, which causes minimized structural damage during the depth profiling of the nanotubular structures. This allows to obtain calibrated sputter rates that account for the nanotubular "porous" morphology. Most importantly, sputter-artifact free compositional profiles of these high aspect ratio 3D structures are obtained, as well as, in combination with SEM, elegant depth sectional imaging.
Analysis and interpretation of lidar observations of the stratospheric aerosol
NASA Technical Reports Server (NTRS)
Hamill, P.; Swissler, T. J.; Osborn, M.; Mccormick, M. P.
1980-01-01
Data obtained with a 48 in. telescope lidar system are compared with results obtained using a one-dimensional stratospheric aerosol model to analyze various microphysical processes influencing the formation of this aerosol. Special attention is given to the following problems: (1) how lidar data can help determine the composition of the aerosol particles and (2) how the layer corresponds to temperature profile variations. The lidar record during the period 1974 to 1979 shows a considerable decrease of the peak value of the backscatter ratio. Seasonal variations in the aerosol layer and a gradual decrease in stratospheric loading are observed. The aerosol model simulates a background stratospheric aerosol layer, and it predicts stratospheric aerosol concentrations and compositions. Numerical experiments are carried out by using the model and by comparing the theoretical results with the experimentally obtained lidar record. Comparisons show that the backscatter profile is consistent with the composition when the particles are sulfuric acid and water; it is not consistent with an ammonium sulfate composition. It is shown that the backscatter ratio is not sensitive to the composition or stratospheric loading of condensation nuclei such as meteoritic debris.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heo, Sung; College of Information and Communication Engineering, Sungkyunkwan University, Cheoncheon-dong 300, Jangan-gu, Suwon 440-746; Lee, Hyung-Ik
2015-06-29
To investigate the band gap profile of Cu(In{sub 1−x},Ga{sub x})(Se{sub 1−y}S{sub y}){sub 2} of various compositions, we measured the band gap profile directly as a function of in-depth using high-resolution reflection energy loss spectroscopy (HR-REELS), which was compared with the band gap profile calculated based on the auger depth profile. The band gap profile is a double-graded band gap as a function of in-depth. The calculated band gap obtained from the auger depth profile seems to be larger than that by HR-REELS. Calculated band gaps are to measure the average band gap of the spatially different varying compositions with respectmore » to considering its void fraction. But, the results obtained using HR-REELS are to be affected by the low band gap (i.e., out of void) rather than large one (i.e., near void). Our findings suggest an analytical method to directly determine the band gap profile as function of in-depth.« less
Blagojević, Polina D; Radulović, Niko S; Skropeta, Danielle
2015-08-01
The plant volatile profile and the essential-oil chemical composition change during the storage of plant material. The objective of this study was to develop a mathematical model able to predict, explain, and quantify these changes. Mathematical equations, derived under the assumption that the essential oil contained within plant material could be treated as an ideal solution (Raoult's law), were applied for tracking of postharvest changes in the volatile profile of Artemisia absinthium L. (the essential oils were analyzed by GC-FID and GC/MS). Starting from a specific chemical composition of an essential-oil sample obtained from plant material after a short drying period (typically 5-10 d), and by using the equations derived from this model, one could easily predict evaporation-induced changes in the volatile profile of the plant material. Based on the composition of the essential-oil sample obtained after a given storage time t, it is possible to identify those components that were involved in chemical reactions, both as reactants and possible products. The established model even allowed the recognition of pairs of transformation, i.e., 'daughter' products and their 'parent' compounds. The obtained results highlight that the essential-oil composition is highly dependent on the storage period of any plant material and urges caution in different types of phytochemical studies, especially chemotaxonomic ones, or practical application. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.
Mass composition results from the Pierre Auger Observatory
NASA Astrophysics Data System (ADS)
Riggi, Simone; Pierre Auger Collaboration
2011-03-01
The present paper reports the recent composition results obtained by the Pierre Auger Observatory using both hybrid and surface detector data. The reconstruction of the shower longitudinal profile and depth of maximum with the fluorescence detector is described. The measured average depth of maximum and its fluctuations as function of the primary energy is presented. The sensitivity of rise time parameters measured with the ground stations and the obtained composition results are discussed.
NASA Technical Reports Server (NTRS)
Stuedemann, W.; Wilken, B.; Kremser, G.; Gloeckler, G.; Ipavich, F. M.
1986-01-01
Ion composition measurements in the entire energy range of the ring current population, obtained with the Charge-, Energy-, Mass-spectrometer instrument on the Charge Composition Explorer in September 1984, are reported. From the energy spectra obtained for all major constituents during the main phase of a magnetic storm, the number densities, energy densities, and mean energies are calculated and displayed as radial profiles. The mean energies of He(2+) are found to be about twice that of H(+) and He(+) throughout this storm, and the time profiles for the mean energies of all major ions are seen to bunch together (when normalizing mean energies by the ionic charge), with the largest variations of the energy densities and mean energies occurring for O(+) ions.
NASA Technical Reports Server (NTRS)
Shenk, William E.; Hope, William A.
1994-01-01
The impact of time compositing on infrared profiling from geosynchronous orbit was evaluated for two convective outbreak cases. Time compositing is the accumulation of the data from several successive images taken at short intervals to provide a single field of measurements with the temporal resolution equal to the time to take all of the images. This is especially effective when the variability of the measurements is slow compared to the image interval. Time compositing should be able to reduce the interference of clouds for infrared measurments since clouds move and change. The convective outbreak cases were on 4 and 21 May 1990 over the eastern Midwest and southeastern United States, respectively. Geostationary Operational Environmental (GOES) Satellite imagery was used to outline clear areas at hourly intervals by two independent analysts. Time compositing was done every 3 h (1330-1530 UTC; 1630-1830 UTC) and over the full 5-h period. For both cases, a significant increase in coverage was measured with each 3-h compositing (about a factor of 2) and a further increase over the full period (approximately a factor of 3). The increase was especially useful in areas of broken cloud cover where large gaps between potential profiling areas on each image were reduced. To provide information on measurement variability over local areas, the regions where the clear-area analyses were done were subdivided into 0.5 deg latitude-longitude boxes, and if some portion of each box was clear, it was assumed that at least one profile could be obtained within the box. In the largest clear areas, at least some portion was clear every hour. Even in the cloudier regions, multiple clear looks possible during the entire period.
Surface compositional profiles of self-assembled InAs/GaAs quantum rings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Magri, Rita; Heun, Stefan; Biasiol, Giorgio
2010-01-04
The surface composition profiles of self-assembled InAs/GaAs quantum rings (QR) are studied both experimentally and theoretically. By using X-ray Photoemission Electron Microscopy (XPEEM) we obtain a 2D composition mapping of unburied rings, which can be directly related to the QR topography measured by Atomic Force Microscopy (AFM). Top-surface composition mapping allows us to obtain information on structures which cannot be directly accessed with cross-sectional studies since overgrowing the QRs with a thick GaAs film alters both their morphology and composition. The 2D surface maps reveal a non-uniform distribution across the rings with an In richer InGaAs alloy in the centralmore » hole regions. Elastic energy calculations via a Valence Force Field (VFF) approach show that, for a given shape of the rings and a fixed total number of Ga and In atoms, an In enrichment of the alloy in the central hole region, together with an In enrichment of the surface layers, leads to a lowering of the total strain energy.« less
NASA Astrophysics Data System (ADS)
Li, Ying; Ke, Chuan; Liu, Xiang; Gou, Fujun; Duan, Xuru; Zhao, Yong
2017-12-01
Liquid metal lithium cause severe corrosion on the surface of metal structure material that used in the blanket and first wall of fusion device. Fast and accurate compositional depth profile measurement for the boundary layer of the corroded specimen will reveal the clues for the understanding and evaluation of the liquid lithium corrosion process as well as the involved corrosion mechanism. In this work, the feasibility of laser-induced breakdown spectroscopy for the compositional depth profile analysis of type 316 stainless steel which was corroded by liquid lithium in certain conditions was demonstrated. High sensitivity of LIBS was revealed especially for the corrosion medium Li in addition to the matrix elements of Fe, Cr, Ni and Mn by the spectral analysis of the plasma emission. Compositional depth profile analysis for the concerned elements which related to corrosion was carried out on the surface of the corroded specimen. Based on the verified local thermodynamic equilibrium shot-by-shot along the depth profile, the matrix effect was evaluated as negligible by the extracted physical parameter of the plasmas generated by each laser pulse in the longitudinal depth profile. In addition, the emission line intensity ratios were introduced to further reduce the impact on the emission line intensity variations arise from the strong inhomogeneities on the corroded surface. Compositional depth profiles for the matrix elements of Fe, Cr, Ni, Mn and the corrosion medium Li were constructed with their measured relative emission line intensities. The distribution and correlations of the concerned elements in depth profile may indicate the clues to the complicated process of composition diffusion and mass transfer. The results obtained demonstrate the potentiality of LIBS as an effective technique to perform spectrochemical measurement in the research fields of liquid metal lithium corrosion.
Baris Yalcin; Steve E Amos; Andrew S D Souza; Craig M Clemons; I Sedat Gunes; Troy K Ista
2012-01-01
Hollow glass microspheres were introduced into wood flour/high density polyethylene composites by melt compounding in a twin-screw extruder. The prepared composites were subsequently converted to extruded profiles in order to obtain composite sheeting. The presence of hollow glass microspheres highly reduced the density of the extruded sheets down to 0.9 g/cc, while...
Gallego, Sergi; Márquez, André; Méndez, David; Marini, Stephan; Beléndez, Augusto; Pascual, Inmaculada
2009-08-01
Photopolymers are appealing materials for the fabrication of diffractive optical elements (DOEs). We evaluate the possibilities of polyvinyl-alcohol/acrylamide-based photopolymers to store diffractive elements with low spatial frequencies. We record gratings with different spatial frequencies in the material and analyze the material behavior measuring the transmitted and the reflected orders as a function of exposition. We study two different compositions for the photopolymer, with and without a cross-linker. The values of diffraction efficiency achieved for both compositions make the material suitable to record DOEs with long spatial periods. Assuming a Fermi-Dirac-function-based profile, we fitted the diffracted intensities (up to the eighth order) to obtain the phase profile of the recorded gratings. This analysis shows that it is possible to achieve a phase shift larger than 2pi rad with steep edges in the periodic phase profile. In the case of the measurements in reflection, we have obtained information dealing with the surface profile, which show that it has a smooth shape with an extremely large phase-modulation depth.
NASA Astrophysics Data System (ADS)
Ding, Anxin; Li, Shuxin; Wang, Jihui; Ni, Aiqing; Sun, Liangliang; Chang, Lei
2016-10-01
In this paper, the corner spring-in angles of AS4/8552 L-shaped composite profiles with different thicknesses are predicted using path-dependent constitutive law with the consideration of material properties variation due to phase change during curing. The prediction accuracy mainly depends on the properties in the rubbery and glassy states obtained by homogenization method rather than experimental measurements. Both analytical and finite element (FE) homogenization methods are applied to predict the overall properties of AS4/8552 composite. The effect of fiber volume fraction on the properties is investigated for both rubbery and glassy states using both methods. And the predicted results are compared with experimental measurements for the glassy state. Good agreement is achieved between the predicted results and available experimental data, showing the reliability of the homogenization method. Furthermore, the corner spring-in angles of L-shaped composite profiles are measured experimentally and the reliability of path-dependent constitutive law is validated as well as the properties prediction by FE homogenization method.
Matrix cracking with irregular fracture fronts as observed in fiber reinforced ceramic composites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu, K.X.; Yeh, C.P.; Wyatt, K.W.
1998-01-01
As a result of matrix cracking in fiber reinforced composites, fracture planforms assume a wide variation of profiles due to the fact that fiber bridging strongly affects the behavior of local crack fronts. This observation raises the question on the legitimacy of commonly used penny-shaped crack solutions when applied to fiber reinforced composites. Accordingly, investigation of the effects of fracture front profiles on mechanical responses is the thrust of this paper. The authors start with the solution of a penny-shaped crack in a unidirectional, fiber reinforced composite, which demonstrates necessity of considering wavy fracture fronts in fiber reinforced composites. Amore » theoretical framework for fiber reinforced composites with irregular fracture fronts due to matrix cracking is then established via a micromechanics model. The difference between small crack-size matrix cracking and large crack-size matrix cracking is investigated in detail. It is shown that the bridging effect is insignificant when matrix crack size is small and solution of effective property are obtained using Mori-Tanaka`s method by treating cracks and reinforcing fibers as distinct, but interacting phases. When the crack size becomes large, the bridging effects has to be taken into consideration. With bridging tractions obtained in consistency with the micromechanics solution, and corresponding crack energy backed out, the effective properties are obtained through a modification of standard Mori-Tanaka`s treatment of multiphase composites. Analytical solutions show that the generalization of a crack density of a penny-shaped planform is insufficient in describing the effective responses of fiber-reinforced composites with matrix cracking. Approximate solutions that account for the effects of the irregularity of crack planforms are given in closed forms for several irregular crack planforms, including cracks of cross rectangle, polygon and rhombus.« less
Roussis; Fitzgerald
2000-04-01
The coupling of gas chromatographic simulated distillation with mass spectrometry for the determination of the distillation profiles of crude oils is reported. The method provides the boiling point distributions of both weight and volume percent amounts. The weight percent distribution is obtained from the measured total ion current signal. The total ion current signal is converted to weight percent amount by calibration with a reference crude oil of a known distillation profile. Knowledge of the chemical composition of the crude oil across the boiling range permits the determination of the volume percent distribution. The long-term repeatability is equivalent to or better than the short-term repeatability of the currently available American Society for Testing and Materials (ASTM) gas chromatographic method for simulated distillation. Results obtained by the mass spectrometric method are in very good agreement with results obtained by conventional methods of physical distillation. The compositional information supplied by the method can be used to extensively characterize crude oils.
Calixto, Clediana Dantas; da Silva Santana, Jordana Kaline; de Lira, Evandro Bernardo; Sassi, Patrícia Giulianna Petraglia; Rosenhaim, Raul; da Costa Sassi, Cristiane Francisca; da Conceição, Marta Maria; Sassi, Roberto
2016-12-01
The potential of four regional microalgae species was evaluated in relation to their cell growth and biomass production when cultured in the following alternative media: bio-composts of fruit/horticultural wastes (HB), sugarcane waste and vinasse (VB) chicken excrements (BCE), raw chicken manure (RCM), and municipal domestic sewage (MDS). The cultures were maintained under controlled conditions and their growth responses, productivities, biochemical compositions, and the ester profiles of their biomasses were compared to the results obtained in the synthetic media. The MDS and HB media demonstrated promising results for cultivation, especially of Chlorella sp., Chlamydomonas sp., and Lagerheimia longiseta, which demonstrated productivities superior to those seen when grown on the control media. The highest lipid levels were obtained with the HB medium. The data obtained demonstrated the viability of cultivating microalgae and producing biomass in alternative media prepared from MDS and HB effluents to produce biodiesel. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bouzas-Cid, Yolanda; Falqué, Elena; Orriols, Ignacio; Mirás-Avalos, José M
2018-02-01
Amino acids and volatile compounds play an important role in wine aroma and sensory characteristics. The concentrations of these compounds might be altered by climate interanual variability and by management practices such as irrigation. The aim of the current study was to assess the amino acid profile of musts and wines, volatile composition and sensory profile of wines from Vitis vinifera (L.) cultivar 'Treixadura' obtained from vines under rain-fed and irrigation conditions over three consecutive vintages (2012-2014). Musts and wines from the irrigation treatment tended to be higher in acidity than those from rain-fed. However, amino acid and aromatic profiles were mostly affected by climate conditions of each year; although irrigation exerted a significant effect on several compounds (proline, cysteine, tryptophan, phenylalanine, α-terpineol and geraniol). Wines from both treatments received similar marks in the sensory tests, suggesting that irrigation did not greatly modify wine quality under the conditions of this study. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Romo, Cynthia Paulinne
High speed digital video images of encased and uncased large-scale explosions of Ammonium Nitrate Fuel Oil (ANFO), and Composition C-4 (C-4) at different masses were analyzed using the background oriented schlieren visualization technique. The encased explosions for ANFO and C-4 took place in the form of car bombs and pipe bombs respectively. The data obtained from the video footage were used to produce shock wave radius vs time profiles, as well as Mach number vs shock wave position profiles. The experimentally measured shock wave data for each explosive material were scaled using Sachs' scaling laws to a 1 kilogram charge at normal temperature and pressure. The results of C-4 were compared to literature, while the results of scaled ANFO were compared to each other, and to the results obtained during the uncased detonations. The comparison between the scaled profiles gathered from the encased and uncased detonations resulted in the identification of the relative amount of energy lost due to the fragmentation of the case. The C-4 profiles were compared to those obtained from computational simulations performed via CTH. The C-4 results showed an agreement in the data reported in literature and that obtained using the background-oriented schlieren (BOS) technique, as well as a good overall agreement with the profiles obtained computationally.
NASA Astrophysics Data System (ADS)
James, H. R.; Gustavsen, R. L.; Dattelbaum, D. M.
2017-01-01
In previous work involving firing flat nosed steel rods into the 60/40 RDX/TNT explosive Composition B-3, we found an apparently anomalous "hump" in particle velocity wave profiles. The "hump" occurred on the center-line established by the rod, and at relatively late times, > 1 µs, after detonation onset. Several explanations, including that of a late time reaction, were postulated. This report will present evidence that the anomalous late time "hump" is due to the arrival of rarefaction waves from the rod's periphery. Simple analytic calculations and reactive-burn hydro-code calculations will be presented supporting this hypothesis.
Vichi, Stefania; Cortés-Francisco, Nuria; Romero, Agustí; Caixach, Josep
2015-03-01
In the present paper, an electrospray ionization (ESI)-Orbitrap method is proposed for the direct chemical profiling of epicuticular wax (EW) from Olea europaea fruit. It constitutes a rapid and efficient tool suitable for a wide-ranging screening of a large number of samples. In a few minutes, the method provides a comprehensive characterization of total EW extracts, based on the molecular formula of their components. Accurate mass measurements are obtained by ultrahigh resolution mass spectrometry, and compositional restrictions are set on the basis of the information available from previous studies of olive EW. By alternating positive and negative ESI modes within the same analysis, complementary results are obtained and a wide range of chemical species is covered. This provides a detailed compositional overview that otherwise would only be available by applying multiple analytical techniques. Copyright © 2015 John Wiley & Sons, Ltd.
Free Vibration of Fiber Composite Thin Shells in a Hot Environment
NASA Technical Reports Server (NTRS)
Gotsis, Pascal K.; Guptill, James D.
1995-01-01
Results are presented of parametric studies to assess the effects of various parameters on the free vibration behavior (natural frequencies) of (plus or minus theta)2, angle-ply fiber composite thin shells in a hot environment. These results were obtained by using a three-dimensional finite element structural analysis computer code. The fiber composite shell is assumed to be cylindrical and made from T-300 graphite fibers embedded in an intermediate-modulus high-strength matrix (IMHS). The residual stresses induced into the laminated structure during curing are taken into account. The following parameters are investigated: the length and the thickness of the shell, the fiber orientations, the fiber volume fraction, the temperature profile through the thickness of the laminate and the different ply thicknesses. Results obtained indicate that: the fiber orientations and the length of the laminated shell had significant effect on the natural frequencies. The fiber volume fraction, the laminate thickness and the temperature profile through the shell thickness had a weak effect on the natural frequencies. Finally, the laminates with different ply thicknesses had insignificant influence on the behavior of the vibrated laminated shell.
Local Displacements and Load Transfer of Shape Memory Alloys in Polymeric Matrices
1997-01-01
plane displacements of room temperature cured SMA ribbon composites were obtained using moiré interferometry. Displacements due to thermal expansion ...141 Figure 6.10 Displacement profiles along SMA ribbon or different values of the coefficient of thermal expansion ...greater importance in polymer composites, which can have large coefficients of thermal expansion . Further, there is also a lack of experimental data
Yang, Xiao-Long; Huang, Le; Ruan, Xiao-Li
2014-01-01
The addition of the DNA methyltransferase inhibitor 500 μM 5-azacytidine to the culture medium of a plant endophytic fungus, Pestalotiopsis crassiuscula, obtained from the leaves of Fragaria chiloensis, dramatically altered the profiles of its metabolites and resulted in the isolation of one new coumarin (1), along with six known compounds (2-7). HPLC profiles revealed that only compounds 3, 4, and 7 belonged to the new induced secondary metabolites. The structures of all isolated compounds were elucidated on the basis of extensive analysis of NMR spectra.
Rosa, A; Piras, A; Nieddu, M; Putzu, D; Cesare Marincola, F; Falchi, A M
2016-09-14
We explored the changes in viability and lipid profile occurring in cancer cells, murine melanoma cells (B16F10 cells) and human cervical carcinoma cells (HeLa cells), when exposed to 24 h-treatments with an n-3 PUFA-rich oil obtained by supercritical extraction with CO2 from Mugil cephalus processed roe (bottarga). The composition of the major lipid classes of bottarga oil was determined by the (13)C NMR technique. Reversed-phase HPLC with DAD/ELSD detection was performed to analyze cells' total fatty acid profile and the levels of phospholipids, total/free cholesterol, triacylglycerols, and cholesteryl esters. Cell-based fluorescent measurements of intracellular membranes and lipid droplets were performed on bottarga oil-treated cells using the Nile red staining technique. The treatments of cancer cells with bottarga oil reduced the viability and affected the fatty acid profile, with a significant n-3 PUFA increase in treated cells. Mullet roe oil uptake modulated the cancer cell lipid composition, inducing a remarkable incorporation of health beneficial n-3 PUFA in the polar and neutral lipid fractions. Bottarga oil treatment influenced the synthesis of intracellular membranes and accumulation of cytoplasmic lipid droplets in cancer cells.
Characteristics of Moderately Deep Tropical Convection Observed by Dual-Polarimetric Radar
NASA Astrophysics Data System (ADS)
Powell, Scott
2017-04-01
Moderately deep cumulonimbus clouds (often erroneously called congestus) over the tropical warm pool play an important role in large-scale dynamics by moistening the free troposphere, thus allowing for the upscale growth of convection into mesoscale convective systems. Direct observational analysis of such convection has been limited despite a wealth of radar data collected during several field experiments in the tropics. In this study, the structure of isolated cumulonimbus clouds, particularly those in the moderately deep mode with heights of up to 8 km, as observed by RHI scans obtained with the S-PolKa radar during DYNAMO is explored. Such elements are first identified following the algorithm of Powell et al (2016); small contiguous regions of echo are considered isolated convection. Within isolated echo objects, echoes are further subdivided into core echoes, which feature vertical profiles reflectivity and differential reflectivity that is similar to convection embedded in larger cloud complexes, and fringe echoes, which contain vertical profiles of differential reflectivity that are more similar to stratiform regions. Between the surface and 4 km, reflectivities of 30-40 (10-20) dBZ are most commonly observed in isolated convective core (fringe) echoes. Convective cores in echo objects too wide to be considered isolated have a ZDR profile that peaks near the surface (with values of 0.5-1 dB common), and decays linearly to about 0.3 dB at and above an altitude of 6 km. Stratiform echoes have a minimum ZDR below of 0-0.5 dB below the bright band and a constant distribution centered on 0.5 dB above the bright band. The isolated convective core and fringe respectively possess composite vertical profiles of ZDR that resemble convective and stratiform echoes. The mode of the distribution of aspect ratios of isolated convection is approximately 2.3, but the long axis of isolated echo objects demonstrates no preferred orientation. An early attempt at illustrating composite radial velocity profiles within isolated convection is made. When the mean flow (determined from sounding data) is subtracted, a clear picture of radial velocities inside a composite representation of convection is obtained. As expected, Doppler radar data shows convergence in the lowest 1-2 km of isolated convective elements and divergence in the upper portions of the clouds. The composite velocity profiles can be used to compute crude profiles of horizontal divergence. Because the analysis uses data along radar rays (with gate size of 150 m) instead of data interpolated to a Cartesian grid, features in composited clouds can be observed at high vertical and horizontal resolution.
Pieper, R; Neumann, K; Kröger, S; Richter, J F; Wang, J; Martin, L; Bindelle, J; Htoo, J K; Vahjen, V; Van Kessel, A G; Zentek, J
2012-12-01
It was recently shown that variations in the ratio of dietary fermentable carbohydrates (fCHO) and fermentable protein (fCP) differentially affect large intestinal microbial ecology and the mucosal response. Here we investigated the use of mass spectrometry to profile changes in metabolite composition in colon and urine associated with variation in dietary fCHO and fCP composition and mucosal physiology. Thirty-two weaned piglets were fed 4 diets in a 2 × 2 factorial design with low fCP and low fCHO, low fCP and high fCHO, high fCP and low fCHO, and high fCP and high fCHO. After 21 to 23 d, all pigs were euthanized and colon digesta and urine metabolite profiles were obtained by mass spectrometry. Analysis of mass spectra by partial least squares approach indicated a clustering of both colonic and urinary profiles for each pig by feeding group. Metabolite identification and annotation using the Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways revealed increased abundance of metabolites associated with arachidonic acid metabolism in colon of pigs fed a high concentration of fCP irrespective of dietary fCHO. Urinary metabolites did not show as clear patterns. Mass spectrometry can effectively differentiate metabolite profiles in colon contents and urine associated with changes in dietary composition. Whether metabolite profiling is an effective tool to identify specific metabolites (biomarkers) or metabolite profiles associated with gut function and integrity needs further elucidation.
Development of a Pipeline for Exploratory Metabolic Profiling of Infant Urine
Jackson, Frances; Georgakopoulou, Nancy; Kaluarachchi, Manuja; Kyriakides, Michael; Andreas, Nicholas; Przysiezna, Natalia; Hyde, Matthew J.; Modi, Neena; Nicholson, Jeremy K.; Wijeyesekera, Anisha; Holmes, Elaine
2017-01-01
Numerous metabolic profiling pipelines have been developed to characterize the composition of human biofluids and tissues, the vast majority of these being for studies in adults. To accommodate limited sample volume and to take into account the compositional differences between adult and infant biofluids, we developed and optimized sample handling and analytical procedures for studying urine from newborns. A robust pipeline for metabolic profiling using NMR spectroscopy was established, encompassing sample collection, preparation, spectroscopic measurement, and computational analysis. Longitudinal samples were collected from five infants from birth until 14 months of age. Methods of extraction and effects of freezing and sample dilution were assessed, and urinary contaminants from breakdown of polymers in a range of diapers and cotton wool balls were identified and compared, including propylene glycol, acrylic acid, and tert-butanol. Finally, assessment of urinary profiles obtained over the first few weeks of life revealed a dramatic change in composition, with concentrations of phenols, amino acids, and betaine altering systematically over the first few months of life. Therefore, neonatal samples require more stringent standardization of experimental design, sample handling, and analysis compared to that of adult samples to accommodate the variability and limited sample volume. PMID:27476583
Properties of anodic oxides grown on a hafnium–tantalum–titanium thin film library
Mardare, Andrei Ionut; Ludwig, Alfred; Savan, Alan; Hassel, Achim Walter
2014-01-01
A ternary thin film combinatorial materials library of the valve metal system Hf–Ta–Ti obtained by co-sputtering was studied. The microstructural and crystallographic analysis of the obtained compositions revealed a crystalline and textured surface, with the exception of compositions with Ta concentration above 48 at.% which are amorphous and show a flat surface. Electrochemical anodization of the composition spread thin films was used for analysing the growth of the mixed surface oxides. Oxide formation factors, obtained from the potentiodynamic anodization curves, as well as the dielectric constants and electrical resistances, obtained from electrochemical impedance spectroscopy, were mapped along two dimensions of the library using a scanning droplet cell microscope. The semiconducting properties of the anodic oxides were mapped using Mott–Schottky analysis. The degree of oxide mixing was analysed qualitatively using x-ray photoelectron spectroscopy depth profiling. A quantitative analysis of the surface oxides was performed and correlated to the as-deposited metal thin film compositions. In the concurrent transport of the three metal cations during oxide growth a clear speed order of Ti > Hf > Ta was proven. PMID:27877648
NASA Astrophysics Data System (ADS)
Volpyas, V. A.; Tumarkin, A. V.; Mikhailov, A. K.; Kozyrev, A. B.; Platonov, R. A.
2016-07-01
A method of ion plasma deposition is proposed for obtaining thin multicomponent films with continuously graded composition in depth of the film. The desired composition-depth profile is obtained by varying the working gas pressure during deposition in the presence of an additional adsorbing screen in the drift space between a sputtered target and substrate. Efficiency of the proposed method is confirmed by Monte Carlo simulation of the deposition of thin films of Ba x Sr1- x TiO3 (BSTO) solid solution. It is demonstrated that, during sputtering of a Ba0.3Sr0.7TiO3 target, the parameter of composition stoichiometry in the growing BSTO film varies in the interval of x = 0.3-0.65 when the gas pressure is changed within 2-60 Pa.
Improving protein complex classification accuracy using amino acid composition profile.
Huang, Chien-Hung; Chou, Szu-Yu; Ng, Ka-Lok
2013-09-01
Protein complex prediction approaches are based on the assumptions that complexes have dense protein-protein interactions and high functional similarity between their subunits. We investigated those assumptions by studying the subunits' interaction topology, sequence similarity and molecular function for human and yeast protein complexes. Inclusion of amino acids' physicochemical properties can provide better understanding of protein complex properties. Principal component analysis is carried out to determine the major features. Adopting amino acid composition profile information with the SVM classifier serves as an effective post-processing step for complexes classification. Improvement is based on primary sequence information only, which is easy to obtain. Copyright © 2013 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mensah, P.F.; Stubblefield, M.A.; Pang, S.S.
Thermal characterization of a prepreg fabric used as the bonding material to join composite pipes has been modeled and solved using finite difference modeling (FDM) numerical analysis technique for one dimensional heat transfer through the material. Temperature distributions within the composite pipe joint are predicted. The prepreg material has temperature dependent thermal properties. Thus the resulting boundary value equations are non linear and analytical solutions cannot be obtained. This characterization is pertinent in determining the temperature profile in the prepreg layer during the manufacturing process for optimization purposes. In addition, in order to assess the effects of induced thermal stressmore » in the joint, the temperature profile is needed. The methodology employed in this analysis compares favorably with data from experimentation.« less
NASA Astrophysics Data System (ADS)
Hobley, Eleanor; Kriegs, Stefanie; Steffens, Markus
2017-04-01
Obtaining reliable and accurate data regarding the spatial distribution of different soil components is difficult due to issues related with sampling scale and resolution on the one hand and laboratory analysis on the other. When investigating the chemical composition of soil, studies frequently limit themselves to two dimensional characterisations, e.g. spatial variability near the surface or depth distribution down the profile, but rarely combine both approaches due to limitations to sampling and analytical capacities. Furthermore, when assessing depth distributions, samples are taken according to horizon or depth increments, resulting in a mixed sample across the sampling depth. Whilst this facilitates mean content estimation per depth increment and therefore reduces analytical costs, the sample information content with regards to heterogeneity within the profile is lost. Hyperspectral imaging can overcome these sampling limitations, yielding high resolution spectral data of down the soil profile, greatly enhancing the information content of the samples. This can then be used to augment horizontal spatial characterisation of a site, yielding three dimensional information into the distribution of spectral characteristics across a site and down the profile. Soil spectral characteristics are associated with specific chemical components of soil, such as soil organic matter or iron contents. By correlating the content of these soil components with their spectral behaviour, high resolution multi-dimensional analysis of soil chemical composition can be obtained. Here we present a hyperspectral approach to the characterisation of soil organic matter and iron down different soil profiles, outlining advantages and issues associated with the methodology.
NASA Astrophysics Data System (ADS)
Yamauchi, K.; Ishikawa, M.; Sato, H.; Iwasaki, T.; Toyoshima, T.
2015-12-01
To understand the dynamics of the lithosphere in subduction systems, the knowledge of rock composition is significant. However, rock composition of the overriding plate is still poorly understood. To estimate rock composition of the lithosphere, it is an effective method to compare the elastic wave velocities measured under the high pressure and temperature condition with the seismic velocities obtained by active source experiment and earthquake observation. Due to an arc-arc collision in central Hokkaido, middle to lower crust is exposed along the Hidaka Metamorphic Belt (HMB), providing exceptional opportunities to study crust composition of an island arc. Across the HMB, P-wave velocity model has been constructed by refraction/wide-angle reflection seismic profiling (Iwasaki et al., 2004). Furthermore, because of the interpretation of the crustal structure (Ito, 2000), we can follow a continuous pass from the surface to the middle-lower crust. We corrected representative rock samples from HMB and measured ultrasonic P-wave (Vp) and S-wave velocities (Vs) under the pressure up to 1.0 GPa in a temperature range from 25 to 400 °C. For example, the Vp values measured at 25 °C and 0.5 GPa are 5.88 km/s for the granite (74.29 wt.% SiO2), 6.02-6.34 km/s for the tonalites (66.31-68.92 wt.% SiO2), 6.34 km/s for the gneiss (64.69 wt.% SiO2), 6.41-7.05 km/s for the amphibolites (50.06-51.13 wt.% SiO2), and 7.42 km/s for the mafic granulite (50.94 wt.% SiO2). And, Vp of tonalites showed a correlation with SiO2 (wt.%). Comparing with the velocity profiles across the HMB (Iwasaki et al., 2004), we estimate that the lower to middle crust consists of amphibolite and tonalite, and the estimated acoustic impedance contrast between them suggests an existence of a clear reflective boundary, which accords well to the obtained seismic reflection profile (Iwasaki et al., 2014). And, we can obtain the same tendency from comparing measured Vp/Vs ratio and Vp/Vs ratio structure model (Matsubara and Obara, 2011).
NASA Technical Reports Server (NTRS)
Festou, M. C.; Atreya, S. K.; Donahue, T. M.; Sandel, B. R.; Shemansky, D. E.; Broadfoot, A. L.
1981-01-01
During the occultation of the star Regulus (B7 type) by Jupiter as seen from the Voyager 2 spacecraft on July 9, 1979, two absorbing regions were detected. Between 911 and 1200 A, H2 was absorbing over a 600 km altitude range. Above 1300 A, the rapid increase of the absorption by the hydrocarbons was observed over an altitude interval of approximately 100 km with a height resolution of 3 km. The analysis of these absorption features has provided the height profiles of molecular hydrogen, methane, ethane, and acetylene, as well as the thermal profile in the upper atmosphere of Jupiter. Combining the Voyager ultraviolet spectrometer results with other data, such as those obtained by the Voyager infrared and radioscience instruments, has yielded a comprehensive model of the composition and structure of the atmosphere of Jupiter.
Isotopic abundances of Hg in mercury stars inferred from the Hg II line at 3984 A
NASA Technical Reports Server (NTRS)
White, R. E.; Vaughan, A. H., Jr.; Preston, G. W.; Swings, J. P.
1976-01-01
Wavelengths of the Hg II absorption feature at 3984 A in 30 Hg stars are distributed uniformly from the value for the terrestrial mix to a value that corresponds to nearly pure Hg-204. The wavelengths are correlated loosely with effective temperatures inferred from Q(UBV). Relative isotopic abundances derived from partially resolved profiles of the 3984-A line in iota CrB, chi Lup, and HR 4072 suggest that mass-dependent fractionation has occurred in all three stars. It is supposed that such fractionation occurs in all Hg stars, and a scheme whereby isotopic compositions can be inferred from a comparison of stellar wavelengths and equivalent widths with those calculated for a family of fractionated isotopic mixes. Theoretical profiles calculated for the derived isotopic composition agree well with high-resolution interferometric profiles obtained for three of the stars.
Composition and Chemistry of the Neutral Atmosphere of Venus
NASA Astrophysics Data System (ADS)
Marcq, Emmanuel; Mills, Franklin P.; Parkinson, Christopher D.; Vandaele, Ann Carine
2018-02-01
This paper deals with the composition and chemical processes occurring in the neutral atmosphere of Venus. Since the last synthesis, observers as well as modellers have emphasised the spatial and temporal variability of minor species, going beyond a static and uniform picture that may have prevailed in the past. The outline of this paper acknowledges this situation and follows closely the different dimensions along which variability in composition can be observed: vertical, latitudinal, longitudinal, temporal. The strong differences between the atmosphere below and above the cloud layers also dictate the structure of this paper. Observational constraints, obtained from both Earth and Venus Express, as well as 1D, 2D and 3D models results obtained since 1997 are also extensively referred and commented by the authors. An non-exhaustive list of topics included follows: modelled and observed latitudinal and vertical profiles of CO and OCS below the clouds of Venus; vertical profiles of CO and SO2 above the clouds as observed by solar occultation and modelled; temporal and spatial variability of sulphur oxides above the clouds. As a conclusion, open questions and topics of interest for further studies are discussed.
Vibration-immune high-sensitivity profilometer built with the technique of composite interferometry.
Lin, Yu-Kai; Chang, Chun-Wei; Hou, Max T; Hsu, I-Jen
2016-03-10
A prototype of a profilometer was built with the technique of composite interferometry for measurement of the distribution of both the amplitude and phase information of the surface of a material simultaneously. The composite interferometer was composed of a Michelson interferometer for measuring the surface profile of the sample and a Mach-Zehnder interferometer for measuring the phase deviation caused by the scanning component and environmental perturbations. A high-sensitivity surface profile can be obtained by use of the phase compensation mechanism through subtraction of the phases of the interferograms detected in the two interferometers. With the new design and improvement of robustness of the optical system, the measurement speed and accuracy were significantly improved. Furthermore, an additional optical delay component results in a higher sensitivity of the interference signal. This prototype of vibration-immune profilometer was examined to have a displacement sensitivity of 0.64 nm.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Félix, Juliana S., E-mail: jfelix@unizar.es; Domeño, Celia, E-mail: cdomeno@unizar.es; Nerín, Cristina, E-mail: cnerin@unizar.es
Graphical abstract: This work details the characterization of VOCs of WPC, produced from residual materials which would have landfills as current destination, and evaluates their odor profile. Highlights: ► More than 140 volatile compounds were identified in raw materials and WPC products. ► Markers were related to the thermal degradation, sawdust or coupling agents. ► WPC prototype showed a characteristic odor profile of burnt, sweet and wax-like. ► Aldehydes, carboxylic acids, ketones and phenols were odor descriptors of WPC. - Abstract: Application of wood plastic composites (WPCs) obtained from recycled materials initially intended for landfill is usually limited by theirmore » composition, mainly focused on release of volatile organic compounds (VOCs) which could affect quality or human safety. The study of the VOCs released by a material is a requirement for new composite materials. Characterization and quantification of VOCs of several WPC produced with low density polyethylene (LDPE) and polyethylene/ethylene vinyl acetate (PE/EVA) films and sawdust were carried out, in each stage of production, by solid phase microextraction in headspace mode (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). An odor profile was also obtained by HS-SPME and GC–MS coupled with olfactometry analysis. More than 140 compounds were observed in the raw materials and WPC samples. Some quantified compounds were considered WPC markers such as furfural, 2-methoxyphenol, N-methylphthalimide and 2,4-di-tert-butylphenol. Hexanoic acid, acetic acid, 2-methoxyphenol, acetylfuran, diacetyl, and aldehydes were the most important odorants. None of the VOCs were found to affect human safety for use of the WPC.« less
Su, Tin Tin; Amiri, Mohammadreza; Mohd Hairi, Farizah; Thangiah, Nithiah; Dahlui, Maznah; Majid, Hazreen Abdul
2015-01-01
This study aims to compare various body composition indices and their association with a predicted cardiovascular disease (CVD) risk profile in an urban population in Kuala Lumpur, Malaysia. A cross-sectional survey was conducted in metropolitan Kuala Lumpur, Malaysia, in 2012. Households were selected using a simple random-sampling method, and adult members were invited for medical screening. The Framingham Risk Scoring algorithm was used to predict CVD risk, which was then analyzed in association with body composition measurements, including waist circumference, waist-hip ratio, waist-height ratio, body fat percentage, and body mass index. Altogether, 882 individuals were included in our analyses. Indices that included waist-related measurements had the strongest association with CVD risk in both genders. After adjusting for demographic and socioeconomic variables, waist-related measurements retained the strongest correlations with predicted CVD risk in males. However, body mass index, waist-height ratio, and waist circumference had the strongest correlation with CVD risk in females. The waist-related indicators of abdominal obesity are important components of CVD risk profiles. As waist-related parameters can quickly and easily be measured, they should be routinely obtained in primary care settings and population health screens in order to assess future CVD risk profiles and design appropriate interventions.
Su, Tin Tin; Amiri, Mohammadreza; Mohd Hairi, Farizah; Thangiah, Nithiah; Dahlui, Maznah; Majid, Hazreen Abdul
2015-01-01
Objectives. This study aims to compare various body composition indices and their association with a predicted cardiovascular disease (CVD) risk profile in an urban population in Kuala Lumpur, Malaysia. Methods. A cross-sectional survey was conducted in metropolitan Kuala Lumpur, Malaysia, in 2012. Households were selected using a simple random-sampling method, and adult members were invited for medical screening. The Framingham Risk Scoring algorithm was used to predict CVD risk, which was then analyzed in association with body composition measurements, including waist circumference, waist-hip ratio, waist-height ratio, body fat percentage, and body mass index. Results. Altogether, 882 individuals were included in our analyses. Indices that included waist-related measurements had the strongest association with CVD risk in both genders. After adjusting for demographic and socioeconomic variables, waist-related measurements retained the strongest correlations with predicted CVD risk in males. However, body mass index, waist-height ratio, and waist circumference had the strongest correlation with CVD risk in females. Conclusions. The waist-related indicators of abdominal obesity are important components of CVD risk profiles. As waist-related parameters can quickly and easily be measured, they should be routinely obtained in primary care settings and population health screens in order to assess future CVD risk profiles and design appropriate interventions. PMID:25710002
Samaram, Shadi; Mirhosseini, Hamed; Tan, Chin Ping; Ghazali, Hasanah Mohd
2013-10-10
The main objective of the current work was to evaluate the suitability of ultrasound-assisted extraction (UAE) for the recovery of oil from papaya seed as compared to conventional extraction techniques (i.e., Soxhlet extraction (SXE) and solvent extraction (SE)). In the present study, the recovery yield, fatty acid composition and triacylglycerol profile of papaya seed oil obtained from different extraction methods and conditions were compared. Results indicated that both solvent extraction (SE, 12 h/25 °C) and ultrasound-assisted extraction (UAE) methods recovered relatively high yields (79.1% and 76.1% of total oil content, respectively). Analysis of fatty acid composition revealed that the predominant fatty acids in papaya seed oil were oleic (18:1, 70.5%-74.7%), palmitic (16:0, 14.9%-17.9%), stearic (18:0, 4.50%-5.25%), and linoleic acid (18:2, 3.63%-4.6%). Moreover, the most abundant triacylglycerols of papaya seed oil were triolein (OOO), palmitoyl diolein (POO) and stearoyl oleoyl linolein (SOL). In this study, ultrasound-assisted extraction (UAE) significantly (p < 0.05) influenced the triacylglycerol profile of papaya seed oil, but no significant differences were observed in the fatty acid composition of papaya seed oil extracted by different extraction methods (SXE, SE and UAE) and conditions.
Fruit Phenolic Profiling: A New Selection Criterion in Olive Breeding Programs
Pérez, Ana G.; León, Lorenzo; Sanz, Carlos; de la Rosa, Raúl
2018-01-01
Olive growing is mainly based on traditional varieties selected by the growers across the centuries. The few attempts so far reported to obtain new varieties by systematic breeding have been mainly focused on improving the olive adaptation to different growing systems, the productivity and the oil content. However, the improvement of oil quality has rarely been considered as selection criterion and only in the latter stages of the breeding programs. Due to their health promoting and organoleptic properties, phenolic compounds are one of the most important quality markers for Virgin olive oil (VOO) although they are not commonly used as quality traits in olive breeding programs. This is mainly due to the difficulties for evaluating oil phenolic composition in large number of samples and the limited knowledge on the genetic and environmental factors that may influence phenolic composition. In the present work, we propose a high throughput methodology to include the phenolic composition as a selection criterion in olive breeding programs. For that purpose, the phenolic profile has been determined in fruits and oils of several breeding selections and two varieties (“Picual” and “Arbequina”) used as control. The effect of three different environments, typical for olive growing in Andalusia, Southern Spain, was also evaluated. A high genetic effect was observed on both fruit and oil phenolic profile. In particular, the breeding selection UCI2-68 showed an optimum phenolic profile, which sums up to a good agronomic performance previously reported. A high correlation was found between fruit and oil total phenolic content as well as some individual phenols from the two different matrices. The environmental effect on phenolic compounds was also significant in both fruit and oil, although the low genotype × environment interaction allowed similar ranking of genotypes on the different environments. In summary, the high genotypic variance and the simplified procedure of the proposed methodology for fruit phenol evaluation seems to be convenient for breeding programs aiming at obtaining new cultivars with improved phenolic profile. PMID:29535752
Fruit Phenolic Profiling: A New Selection Criterion in Olive Breeding Programs.
Pérez, Ana G; León, Lorenzo; Sanz, Carlos; de la Rosa, Raúl
2018-01-01
Olive growing is mainly based on traditional varieties selected by the growers across the centuries. The few attempts so far reported to obtain new varieties by systematic breeding have been mainly focused on improving the olive adaptation to different growing systems, the productivity and the oil content. However, the improvement of oil quality has rarely been considered as selection criterion and only in the latter stages of the breeding programs. Due to their health promoting and organoleptic properties, phenolic compounds are one of the most important quality markers for Virgin olive oil (VOO) although they are not commonly used as quality traits in olive breeding programs. This is mainly due to the difficulties for evaluating oil phenolic composition in large number of samples and the limited knowledge on the genetic and environmental factors that may influence phenolic composition. In the present work, we propose a high throughput methodology to include the phenolic composition as a selection criterion in olive breeding programs. For that purpose, the phenolic profile has been determined in fruits and oils of several breeding selections and two varieties ("Picual" and "Arbequina") used as control. The effect of three different environments, typical for olive growing in Andalusia, Southern Spain, was also evaluated. A high genetic effect was observed on both fruit and oil phenolic profile. In particular, the breeding selection UCI2-68 showed an optimum phenolic profile, which sums up to a good agronomic performance previously reported. A high correlation was found between fruit and oil total phenolic content as well as some individual phenols from the two different matrices. The environmental effect on phenolic compounds was also significant in both fruit and oil, although the low genotype × environment interaction allowed similar ranking of genotypes on the different environments. In summary, the high genotypic variance and the simplified procedure of the proposed methodology for fruit phenol evaluation seems to be convenient for breeding programs aiming at obtaining new cultivars with improved phenolic profile.
Rivera-Rangel, L R; Aguilera-Campos, K I; García-Triana, A; Ayala-Soto, J G; Chavez-Flores, D; Hernández-Ochoa, L
2018-01-01
Two different extraction processes, Soxhlet and ultrasound, were used to obtain the oil extracts of Western Schley, Wichita, and Native pecan nuts cultured in Chihuahua, Mexico. The aspects evaluated in this study were the extraction yield of the processes and fatty acids' profile of the resulting extracts. Gas chromatography coupled with mass spectrometry (GC-MS) was used to identify and determine the composition percentage of fatty acids present in pecan nuts oils extracted. The results obtained show that higher oil extraction yields were obtained by Soxhlet method with hexane (69.90%) in Wichita varieties. Wichita, Western Schley, and Native pecan nuts from Chihuahua are rich in PUFA (polyunsaturated fatty acids) and MUFA (monounsaturated fatty acids) and have low levels of SFA (saturated fatty acids). The predominant fatty acid present in all pecan nuts oils was linoleic acid followed by oleic acid. Myristic acid, palmitic acid, and linolenic acid were also identified in representative quantities. The results from this study suggest that there are statistically significant differences in the chemical composition of the pecan nuts oils extracted from the varieties cultured in Chihuahua, Mexico, and those cultivated in other regions of the world.
Rivera-Rangel, L. R.; Aguilera-Campos, K. I.; García-Triana, A.; Ayala-Soto, J. G.; Chavez-Flores, D.
2018-01-01
Two different extraction processes, Soxhlet and ultrasound, were used to obtain the oil extracts of Western Schley, Wichita, and Native pecan nuts cultured in Chihuahua, Mexico. The aspects evaluated in this study were the extraction yield of the processes and fatty acids' profile of the resulting extracts. Gas chromatography coupled with mass spectrometry (GC-MS) was used to identify and determine the composition percentage of fatty acids present in pecan nuts oils extracted. The results obtained show that higher oil extraction yields were obtained by Soxhlet method with hexane (69.90%) in Wichita varieties. Wichita, Western Schley, and Native pecan nuts from Chihuahua are rich in PUFA (polyunsaturated fatty acids) and MUFA (monounsaturated fatty acids) and have low levels of SFA (saturated fatty acids). The predominant fatty acid present in all pecan nuts oils was linoleic acid followed by oleic acid. Myristic acid, palmitic acid, and linolenic acid were also identified in representative quantities. The results from this study suggest that there are statistically significant differences in the chemical composition of the pecan nuts oils extracted from the varieties cultured in Chihuahua, Mexico, and those cultivated in other regions of the world. PMID:29610686
Detailed mechanism for oxidation of benzene
NASA Technical Reports Server (NTRS)
Bittker, David A.
1990-01-01
A detailed mechanism for the oxidation of benzene is presented and used to compute experimentally obtained concentration profiles and ignition delay times over a wide range of equivalence ratio and temperature. The computed results agree qualitatively with all the experimental trends. Quantitative agreement is obtained with several of the composition profiles and for the temperature dependence of the ignition delay times. There are indications, however, that some important reactions are as yet undiscovered in this mechanism. Recent literature expressions have been used for the rate coefficients of most important reactions, except for some involving phenol. The discrepancy between the phenol pyrolysis rate coefficient used in this work and a recent literature expression remains to be explained.
NASA Astrophysics Data System (ADS)
Ponomarev, V. I.; Konovalikhin, S. V.; Kovalev, I. D.; Vershinnikov, V. I.
2015-09-01
Splitting of reflections from boron carbide has been found for the first time by an X-ray diffraction study of polycrystalline mixture of boron carbide В15- х С х , (1.5 ≤ x ≤ 3) and its magnesium derivative C4B25Mg1.42. An analysis of reflection profiles shows that this splitting is due to the presence of boron carbide phases of different compositions in the sample, which are formed during crystal growth. The composition changes from В12.9С2.1 to В12.4С2.6.
Properties of thermal air plasma with admixing of copper and carbon
NASA Astrophysics Data System (ADS)
Fesenko, S.; Veklich, A.; Boretskij, V.; Cressault, Y.; Gleizes, A.; Teulet, Ph
2014-11-01
This paper deals with investigations of air plasma with admixing of copper and carbon. Model plasma source unit with real breaking arc was used for the simulation of real discharges, which can be occurred during sliding of Cu-C composite electrodes on copper wire at electromotive vehicles. The complex technique of plasma property studies is developed. From one hand, the radial profiles of temperature and electron density in plasma of electric arc discharge in air between Cu-C composite and copper electrodes in air flow were measured by optical spectroscopy techniques. From another hand, the radial profiles of electric conductivity of plasma mixture were calculated by solution of energy balance equation. It was assumed that the thermal conductivity of air plasma is not depending on copper or carbon vapor admixtures. The electron density is obtained from electric conductivity profiles by calculation in assumption of local thermodynamic equilibrium in plasma. Computed in such way radial profiles of electron density in plasma of electric arc discharge in air between copper electrodes were compared with experimentally measured profiles. It is concluded that developed techniques of plasma diagnostics can be reasonably used in investigations of thermal plasma with copper and carbon vapors.
Moving bed reactor setup to study complex gas-solid reactions.
Gupta, Puneet; Velazquez-Vargas, Luis G; Valentine, Charles; Fan, Liang-Shih
2007-08-01
A moving bed scale reactor setup for studying complex gas-solid reactions has been designed in order to obtain kinetic data for scale-up purpose. In this bench scale reactor setup, gas and solid reactants can be contacted in a cocurrent and countercurrent manner at high temperatures. Gas and solid sampling can be performed through the reactor bed with their composition profiles determined at steady state. The reactor setup can be used to evaluate and corroborate model parameters accounting for intrinsic reaction rates in both simple and complex gas-solid reaction systems. The moving bed design allows experimentation over a variety of gas and solid compositions in a single experiment unlike differential bed reactors where the gas composition is usually fixed. The data obtained from the reactor can also be used for direct scale-up of designs for moving bed reactors.
Rossi, F E; Diniz, T A; Neves, L M; Fortaleza, A C S; Gerosa-Neto, J; Inoue, D S; Buonani, C; Cholewa, J M; Lira, F S; Freitas, I F
2017-05-01
Aerobic and concurrent training (CT, aerobic and strength training) improves body composition and metabolic profile; however, it is not known whether these positive outcomes acquired after aerobic or CT are maintained long term (⩾6 months) after program interruption in postmenopausal women. This study investigated the changes in total and appendicular body composition, bone mineral density and metabolic profile following 16 weeks of aerobic or CT, and through 6 months and 1 year of detraining in postmenopausal women. In total, 60 postmenopausal women were divided into the following groups: aerobic (AT), aerobic plus strength training (CT) and control group (CG), and 31 participants were assessed for the 1 year follow-up. Body composition and bone mineral density were evaluated by dual-energy X-ray absorptiometry (DXA), and total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triacylglycerol, glucose, insulin, leptin, adiponectin and plasminogen activator inhibitor-1 (PAI-1) were assessed. There were main effects of time for arm fat mass, arm lean mass and trunk lean mass (P<0.05). There was a statistical difference between AT and CG for leg fat mass and percentage of fat (P<0.05). After 6 months of detraining, leg lean mass decreased in relation to post-intervention, and there was a statistically significant interaction for total and appendicular lean mass (P<0.05). There were differences between CT and CG in glucose and between AT and CG in glucose and triacylglycerol (P<0.05). A duration of 16 weeks of aerobic or CT improved total and appendicular body composition and metabolic profile but after 6 months of detraining, leg lean mass returned to the values obtained pre-training in CT.
Usefulness of Fatty Acid Composition for Differentiation of Legionella Species
Diogo, Alexandra; Veríssimo, António; Nobre, M. Fernanda; da Costa, Milton S.
1999-01-01
Numerical analysis of fatty acid methyl ester (FAME) profiles of 199 isolates and 76 reference strains, belonging to all validly described species of the genus Legionella that can be cultured in laboratory media, was used to differentiate between the species of this genus. With the exception of the strains that autofluoresced red, it was possible to differentiate all the other Legionella species. The strains of the species L. bozemanii, L. dumoffii, L. feeleii, L. gormanii, L. maceachernii, L. micdadei, and L. quinlivanii did not form single clusters, showing some degree of variability in the fatty acid compositions. The strains of the blue-white autofluorescent species had very similar fatty acid compositions and were difficult to distinguish from each other. Nine isolates had fatty acid profiles unlike those of any of the validly described species and may represent different FAME groups of known species or undescribed Legionella species. The method used in this study was useful for screening and discriminating large number of isolates of Legionella species. Moreover, the results obtained can be included in a database of fatty acid profiles, leading to a more accurate automatic identification of Legionella isolates. PMID:10364593
Compton profiles of some composite materials normalized by a new method
NASA Astrophysics Data System (ADS)
Sankarshan, B. M.; Umesh, T. K.
2018-03-01
Recently, we have shown that as a novel approach, in the case of samples which can be treated as pure incoherent scatterers, the effective atomic number Zeff itself could be conveniently used to normalize their un-normalized Compton profiles. In the present investigation, we have attempted to examine the efficacy of this approach. For this purpose, we have first determined the single differential Compton scattering cross sections (SDCS) of the elements C and Al as well as of some H, C, N and O based polymer samples such as bakelite, epoxy, nylon and teflon which are pure incoherent scatterers. The measurements were made at 120° in a goniometer assembly that employs a high resolution high purity germanium detector. The SDCS values were used to obtain the Zeff and the un-normalized Compton profiles. These Compton profiles were separately normalized with their Zeff values (for Compton scattering) as well as with the normalization constant obtained by integrating their Hartree-Fock Biggs et al Compton profiles based on the mixture rule. These two sets of values agreed well within the range of experimental errors, implying that Zeff can be conveniently used to normalize the experimental Compton profiles of pure incoherent scatterers.
Evaluation of 1H NMR metabolic profiling using biofluid mixture design.
Athersuch, Toby J; Malik, Shahid; Weljie, Aalim; Newton, Jack; Keun, Hector C
2013-07-16
A strategy for evaluating the performance of quantitative spectral analysis tools in conditions that better approximate background variation in a metabonomics experiment is presented. Three different urine samples were mixed in known proportions according to a {3, 3} simplex lattice experimental design and analyzed in triplicate by 1D (1)H NMR spectroscopy. Fifty-four urinary metabolites were subsequently quantified from the sample spectra using two methods common in metabolic profiling studies: (1) targeted spectral fitting and (2) targeted spectral integration. Multivariate analysis using partial least-squares (PLS) regression showed the latent structure of the spectral set recapitulated the experimental mixture design. The goodness-of-prediction statistic (Q(2)) of each metabolite variable in a PLS model was calculated as a metric for the reliability of measurement, across the sample compositional space. Several metabolites were observed to have low Q(2) values, largely as a consequence of their spectral resonances having low s/n or strong overlap with other sample components. This strategy has the potential to allow evaluation of spectral features obtained from metabolic profiling platforms in the context of the compositional background found in real biological sample sets, which may be subject to considerable variation. We suggest that it be incorporated into metabolic profiling studies to improve the estimation of matrix effects that confound accurate metabolite measurement. This novel method provides a rational basis for exploiting information from several samples in an efficient manner and avoids the use of multiple spike-in authentic standards, which may be difficult to obtain.
Uprety, Bijaya K; Rakshit, Sudip K
2017-12-01
Tailoring lipids from oleaginous yeasts to contain specific types of fatty acid is of considerable interest to food, fuel, and pharmaceutical industries. In this study, the essential oil obtained from Citrus sinesus L. has been used to alter the fatty acid composition of two common oleaginous yeasts, Rhodosporidium toruloides and Cryptococcus curvatus. With increasing levels of essential oil in the medium, the metabolic flux of the fatty acid biosynthesis pathway shifted towards saturated fatty acid production. Essential oil reduced the activities of elongase and ∆9 desaturase. This made the lipid obtained from both these yeasts rich in saturated fatty acids. At certain specific concentrations of the essential oil in the medium, the lipid obtained from R. toruloides and C. curvatus cultures was similar to mahuwa butter and palm oil, respectively. Limonene is the major constituents of orange essential oil. Its effect on one of the oleaginous yeasts, R. toruloides, was also studied separately. Effects similar to orange essential oil were obtained with limonene. Thus, we can conclude that limonene in orange essential oil brings about compositional change of microbial lipid produced in this organism.
NASA Astrophysics Data System (ADS)
Sekine, Hideki; Yoshida, Kimiaki
This paper deals with the optimization problem of material composition for minimizing the stress intensity factor of radial edge crack in thick-walled functionally graded material (FGM) circular pipes under steady-state thermomechanical loading. Homogenizing the FGM circular pipes by simulating the inhomogeneity of thermal conductivity by a distribution of equivalent eigentemperature gradient and the inhomogeneity of Young's modulus and Poisson's ratio by a distribution of equivalent eigenstrain, we present an approximation method to obtain the stress intensity factor of radial edge crack in the FGM circular pipes. The optimum material composition for minimizing the stress intensity factor of radial edge crack is determined using a nonlinear mathematical programming method. Numerical results obtained for a thick-walled TiC/Al2O3 FGM circular pipe reveal that it is possible to decrease remarkably the stress intensity factor of radial edge crack by setting the optimum material composition profile.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meng, Yifei; Kim, Honggyu; Zuo, Jian-Min
2014-07-07
We propose a digital model for high quality superlattices by including fluctuations in the superlattice periods. The composition and strain profiles are assumed to be coherent and persist throughout the superlattice. Using this model, we have significantly improved the fit with experimental X-ray diffraction data recorded from the nominal InAs/GaSb superlattice. The lattice spacing of individual layers inside the superlattice and the extent of interfacial intermixing are refined by including both (002) and (004) and their satellite peaks in the fitting. For the InAs/GaSb strained layer superlattice, results show: (i) the GaSb-on-InAs interface is chemically sharper than the InAs-on-GaSb interface,more » (ii) the GaSb layers experience compressive strain with In incorporation, (iii) there are interfacial strain associated with InSb-like bonds in GaSb and GaAs-like bonds in InAs, (iv) Sb substitutes a significant amount of In inside InAs layer near the InAs-on-GaSb interface. For support, we show that the composition profiles determined by X-ray diffraction are in good agreement with those obtained from atom probe tomography measurement. Comparison with the kinetic growth model shows a good agreement in terms of the composition profiles of anions, while the kinetic model underestimates the intermixing of cations.« less
Thermal transport through Ge-rich Ge/Si superlattices grown on Ge(0 0 1)
NASA Astrophysics Data System (ADS)
Thumfart, L.; Carrete, J.; Vermeersch, B.; Ye, N.; Truglas, T.; Feser, J.; Groiss, H.; Mingo, N.; Rastelli, A.
2018-01-01
The cross-plane thermal conductivities of Ge-rich Si/Ge superlattices have been measured using both time-domain thermoreflectance and the differential 3ω method. The superlattices were grown by molecular beam epitaxy on Ge(0 0 1) substrates. Crystal quality and structural information were investigated by x-ray diffractometry and transmission electron microscopy. The influence of segregation during growth on the composition profiles was modeled using the experimental growth temperatures and deposition rates. Those profiles were then employed to obtain parameter-free theoretical estimates of the thermal conductivity by combining first-principles calculations, Boltzmann transport theory and phonon Green’s functions. Good agreement between theory and experiment is observed. The thermal conductivity shows a strong dependence on the composition and the thickness of the samples. Moreover, the importance of the composition profile is reflected in the fact that the thermal conductivity of the superlattices is considerably lower than predicted values for alloys with the same average composition and thickness. Measurement on different samples with the same Si layer thickness and number of periods, but different Ge layer thickness, show that the thermal resistance is only weakly dependent on the Ge layers. We analyze this phenomenon based on the first-principles mode, and build an approximate parametrization showing that, in this regime, the resistivity of a SL is roughly linear on the amount of Si.
Profiling of oligolignols reveals monolignol coupling conditions in lignifying poplar xylem
Kris Morreel; John Ralph; Hoon Kim; Fachuang Lu; Geert Goeminne; Sally Ralph; Eric Messens; Wout Boerjan
2004-01-01
Lignin is an aromatic heteropolymer, abundantly present in the walls of secondary thickened cells. Although much research has been devoted to the structure and composition of the polymer to obtain insight into lignin polymerization, the low-molecular weight oligolignol fraction has escaped a detailed characterization. This fraction, in contrast to the rather...
Sayago, Carla T M; Camargo, Vanessa B; Barbosa, F; Gularte, Cláudia; Pereira, Geovana; Miotto, Silvia; Cechinel Filho, V; Luiz Puntel, R; Folmer, V; Mendez, A
2013-03-01
Bauhinia species are known to have hypoglycemiant and antioxidant activities. Here, hydro-ethanolic leaf extracts from Bauhinia forficata subsp. pruinosa and Bauhinia variegata, collected in a Pampa biome region of Brazil, were investigated to characterize their chromatographic profile, flavonoid content and in vitro antioxidant activity (TBARS and DPH assays). The extracts were obtained from dried and fresh leaves. The total flavonoid content was assessed by spectrophotometric determination, and the results ranged between 572.08 and 1,102.99 μg mL-1. Moreover, flavonoids were more predominant in B. variegata than in B. forficata subsp. pruinosa. HPLC analysis detected a complex profile of phenolic compounds, being the flavonoid kaempferitrin founded B. forficata subsp. pruinosa; in addition, other kaempferol and quercetin derivatives were present. In vitro antioxidant assays demonstrated a different behavior depending on the species, leaf treatment and extract concentration. In general, B. variegata extracts obtained from fresh material presented higher antioxidant potential, which can be attributed to the predominance of flavonoids in their chemical composition.
NASA Technical Reports Server (NTRS)
Sasano, Y.; Browell, E. V.
1986-01-01
Aerosols are often classified into several general types according to their origins and composition, such as maritime, continental, and stratospheric aerosols, and these aerosol types generally have different characteristics in chemical and physical properties. The present study aims at demonstrating the potential for distinguishing these aerosol types by the wavelength dependence of their backscatter coefficients obtained from quantitative analyses of multiple wavelength lidar signals. Data from the NASA Airborne Differential Abosrption lidar (DIAL) S ystems, which can measure aerosol backscatter profiles at wavelenghts of 300, 600, and 1064 nm and ozone profiles of backscatter coefficients for these three wavelength were derived from the observations of aerosols of different types. Observations were performed over the Atlantic Ocean, the Southwestern United States, and French Guyana.
Liu, Yufei; Wang, Chang; Wang, Ran; Wu, Yike; Zhang, Liang; Liu, Bi-Feng; Cheng, Liming; Liu, Xin
2018-06-15
Glycosylation is one of the most important post-translational modifications of protein. Recently, global profiling of human serum glycomics has become a noninvasive method for cancer-related biomarker discovery and many studies have focused on compositional glycan profiling. In contrast, structure-specific glycan profiling may provide more potential biomarkers with higher specificity than compositional profiling. In this work, N-glycans released from human serum were neutralized with methylamine and reduced by ammonia-borane complex prior to profiling using nanoLC-ESI-MS with porous graphitized carbon (PGC) and relative abundances of over 280 isomers were compared between pancreatic cancer (PC) cases (n = 32) and healthy controls (n = 32). Statistical analysis identified 25 specific-isomeric biomarkers with significant differences (p-value < 0.05). ROC and PCA analysis were performed to assess the potential biomarkers which were identified as being significantly altered in cancer. The AUCs of the significantly changed specific-isomers were ranging from 0.712 to 0.949. In addition, with the combination of all potential biomarkers, a higher AUC of 0.976 with sensitivity (93.5%) and specificity (90.6%) was obtained. Overall, the proposed strategy coupled to relative quantitative analysis of isomeric glycans make it possible to discover new biomarkers for the diagnosis of PC. Pancreatic cancer (PC) has a poor prognosis with a five-year survival rate <5%. Therefore, a strategy for accurate diagnosis of PC is indeed required. In this paper, a dual-derivatized strategy for structure-specific glycan profiling has been used and according to our best knowledge, this is the first application of this strategy for PC biomarker discovery, in which the separation, identification and relative quantification of isomeric glycans can be simultaneously obtained. In addition, by in-depth analysis of isomeric glycans, the full description of the stereo- and region- diversity of glycans can also be achieved, which might provide more potential information for PC biomarker discovery. Copyright © 2018 Elsevier B.V. All rights reserved.
The Relationship between Ionospheric Slab Thickness and the Peak Density Height, hmF2
NASA Astrophysics Data System (ADS)
Meehan, J.; Sojka, J. J.
2017-12-01
The electron density profile is one of the most critical elements in the ionospheric modeling-related applications today. Ionosphere parameters, hmF2, the height of the peak density layer, and slab thickness, the ratio of the total electron content, TEC, to the peak density value, NmF2, are generally obtained from any global sounding observation network and are easily incorporated into models, theoretical or empirical, as numerical representations. Slab thickness is a convenient one-parameter summary of the electron density profile and can relate a variety of elements of interest that effect the overall electron profile shape, such as the neutral and ionospheric temperatures and gradients, the ionospheric composition, and dynamics. Using ISR data from the 2002 Millstone Hill ISR data campaign, we found, for the first time, slab thickness to be correlated to hmF2. For this, we introduce a new ionospheric index, k, which ultimately relates electron density parameters and can be a very useful tool for describing the topside ionosphere shape. Our study is an initial one location, one season, 30-day study, and future work is needed to verify the robustness of our claim. Generally, the ionospheric profile shape, requires knowledge of several ionospheric parameters: electron, ion and neutral temperatures, ion composition, electric fields, and neutral winds, and is dependent upon seasons, local time, location, and the level of solar and geomagnetic activity; however, with this new index, only readily-available, ionospheric density information is needed. Such information, as used in this study, is obtained from a bottomside electron density profile provided by an ionosonde, and TEC data provided by a local, collocated GPS receiver.
Gómez, Marta; Moles, Laura; Espinosa-Martos, Irene; Bustos, Gerardo; de Vos, Willem M.; Rodríguez, Juan M.; Fuentes, Susana
2017-01-01
An abnormal colonization pattern of the preterm gut may affect immune maturation and exert a long-term influence on the intestinal bacterial composition and host health. However, follow-up studies assessing the evolution of the fecal microbiota of infants that were born preterm are very scarce. In this work, the bacterial compositions of fecal samples, obtained from sixteen 2-year-old infants were evaluated using a phylogenetic microarray; subsequently, the results were compared with those obtained in a previous study from samples of meconium and feces collected from the same infants while they stayed in the neonatal intensive care unit (NICU). In parallel, the concentration of a wide range of cytokines, chemokines, growth factors and immunoglobulins were determined in meconium and fecal samples. Globally, a higher bacterial diversity and a lower interindividual variability were observed in 2-year-olds’ feces, when compared to the samples obtained during their first days of life. Hospital-associated fecal bacteria, that were dominant during the NICU stay, seemed to be replaced, two years later, by genera, which are usually predominant in the healthy adult microbiome. The immune profile of the meconium and fecal samples differed, depending on the sampling time, showing different immune maturation statuses of the gut. PMID:29186903
Low-energy particle population. [in Jupiter magnetosphere
NASA Technical Reports Server (NTRS)
Krimigis, S. M.; Roelof, E. C.
1983-01-01
A review is conducted of the measurements of the intensities, energy spectra, angular variations, and composition characteristics of the low-energy ion population in and around the Jovian magnetosphere, taking into account data obtained by both Voyager spacecraft. A description is provided of some novel analysis techniques which have been employed to generate density, pressure, composition, and plasma flow profiles in the magnetosphere. The obtained results are compared with data reported in connection with other investigations related to the spacecraft. Attention is given to the Low-Energy Charged Particle investigation, the Voyager 1 and 2 trajectories within 1000 Jupiter radii, and a hot plasma model of the Jovian magnetosphere. The measurement of hot multispecies convected plasmas using energetic particle detectors is also discussed.
IBA analysis of some precolumbian gilded-copper samples
NASA Astrophysics Data System (ADS)
Andrade, E.; Murillo, G.; Policroniades, R.; Acosta, L.; Zavala, E. P.; Rocha, M. F.; Centeno, S. A.
2005-10-01
The elemental composition and depth profiles obtained by IBA techniques on some gilded-copper fragments from the Moche site of Loma Negra, in the Piura Valley, on the Northern Coast of Perú are presented in this article. A previous radiocarbon dating of a wooden fragment indicated that Loma Negra was occupied around 295 AD. A PIXE analysis using a 2.6 MeV external proton beam, was used to obtain the concentration of trace elements in the samples. RBS analyses using 2.72 MeV 4He+ and 12.0 MeV 12C3+ were used to obtain the Au, Ag, Cu atomic profiles. NRA with a 1.02 MeV deuteron beam was used to measure the oxygen and carbon concentrations through the 16O(d,p) 17O, 16O(d,α) 14N and 12C(d,p0) 13C reactions.
NASA Astrophysics Data System (ADS)
Kavalerov, B. V.; Anoshkin, A. N.; Osokin, V. M.; Tretyakov, A. A.; Potrakhov, N. N.; Bessonov, V. B.; Obodovskiy, A. V.
2018-02-01
The advantages of using the method of microfocus radiography in the non-destructive testing of aviation products are considered in the paper, using the example of a circular beam of a U-shaped profile made of polymer composite materials. The basic types of characteristic defects of parts arising in such a type are described both in the process of their manufacture and in the process of their exploitation, namely interlayer delaminations, pores and folds. Peculiarities of obtaining pseudo-volumetric images, which allow to increase the informativity about the structure of the object of control, as well as to identify the arising heterogeneities are given. A model of a robotic system is described that makes it possible to realize a small or multi-angle survey scheme, and, in particular, to carry out tomographic studies.
Models of Mars' atmosphere (1974)
NASA Technical Reports Server (NTRS)
1974-01-01
Atmospheric models for support of design and mission planning of space vehicles that are to orbit the planet Mars, enter its atmosphere, or land on the surface are presented. Quantitative data for the Martian atmosphere were obtained from Earth-base observations and from spacecraft that have orbited Mars or passed within several planetary radii. These data were used in conjunction with existing theories of planetary atmospheres to predict other characteristics of the Martian atmosphere. Earth-based observations provided information on the composition, temperature, and optical properties of Mars with rather coarse spatial resolution, whereas spacecraft measurements yielded data on composition, temperature, pressure, density, and atmospheric structure with moderately good spatial resolution. The models provide the temperature, pressure, and density profiles required to perform basic aerodynamic analyses. The profiles are supplemented by computed values of viscosity, specific heat, and speed of sound.
Jeleń, Henryk H; Gracka, Anna
2015-10-30
Solid phase microextraction (SPME) is widely used in food flavor compounds analysis in majority for profiling volatile compounds. Based on such profiles conclusions are often drawn concerning the percentage composition of volatile compounds in particular food, spices or raw materials. This paper focuses on the usefulness of SPME for the profiling of volatile compounds from spices using black pepper as an example. SPME profiles obtained in different analytical conditions were compared to the profile of pepper volatiles obtained using hydrodistillation in Clevenger apparatus. The profiles of both monoterpenes and sesquiterpenes of black pepper were highly dependent on sample weight (0.1 and 1g samples were tested), and extraction time (durations from 2 to 120min were tested), regardless of the SPME fiber used (PDMS and CAR/PDMS coatings were used). The characteristic phenomenon for extraction from dry ground pepper was the decrease of monoterpenes % share in volatiles with increasing extraction times, whereas at the same time the % contents of sesquiterpenes increased. Addition of water to ground pepper substantially changed extraction kinetics and mutual proportions of mono to sesquiterpenes compared to dry samples by minimizing changes in mono- to sesquiterpenes ratio in different extraction times. Obtained results indicate that SPME can be a fast extraction method for volatiles of black pepper. Short extraction times (2-10min) in conjunction with the fast GC analysis (2.1min) proposed here may offer fast alternative to hydrodistillation allowing black pepper terpenes characterization. Copyright © 2015 Elsevier B.V. All rights reserved.
Embedded function methods for supersonic turbulent boundary layers
NASA Technical Reports Server (NTRS)
He, J.; Kazakia, J. Y.; Walker, J. D. A.
1990-01-01
The development of embedded functions to represent the mean velocity and total enthalpy distributions in the wall layer of a supersonic turbulent boundary layer is considered. The asymptotic scaling laws (in the limit of large Reynolds number) for high speed compressible flows are obtained to facilitate eventual implementation of the embedded functions in a general prediction method. A self-consistent asymptotic structure is derived, as well as a compressible law of the wall in which the velocity and total enthalpy are logarithmic within the overlap zone, but in the Howarth-Dorodnitsyn variable. Simple outer region turbulence models are proposed (some of which are modifications of existing incompressible models) to reflect the effects of compressibility. As a test of the methodology and the new turbulence models, a set of self-similar outer region profiles is obtained for constant pressure flow; these are then coupled with embedded functions in the wall layer. The composite profiles thus obtained are compared directly with experimental data and good agreement is obtained for flows with Mach numbers up to 10.
Nonlinear propagation of electromagnetic waves in negative-refraction-index composite materials.
Kourakis, I; Shukla, P K
2005-07-01
We investigate the nonlinear propagation of electromagnetic waves in left-handed materials. For this purpose, we consider a set of coupled nonlinear Schrödinger (CNLS) equations, which govern the dynamics of coupled electric and magnetic field envelopes. The CNLS equations are used to obtain a nonlinear dispersion, which depicts the modulational stability profile of the coupled plane-wave solutions in left-handed materials. An exact (in)stability criterion for modulational interactions is derived, and analytical expressions for the instability growth rate are obtained.
NASA Astrophysics Data System (ADS)
Ke, Haohao
Receptor models have been widely used in air quality studies to identify pollution sources and estimate their contributions. A common problem for most current receptor models is insufficient consideration of realistic constraints such as can be obtained from emission inventories, chemical composition profiles of the sources, and the physics of plume dispersion. In addition, poor resolving of collinear sources was often found. With the high quality time-, composition-, and size-resolved measurements during the EPA Supersite project, efforts towards resolving nearby industrial sources were made by combinative use of Positive Matrix Factorization (PMF) and the Pseudo-Deterministic Receptor Model (PDRM). The PMF modeling of Baltimore data in September 2001 revealed coal-fired and oil-fired power plants (CFPP and OFPP, respectively) with significant cross contamination, as indicated by the high Se/Ni ratio in the OFPP profile. Nevertheless, the PMF results provided a good estimate of background and the PMF-constrained emission rates well seeded the trajectory-driven PDRM modeling. Using NOx as the tracer gas for chi/Q tuning, ultimately resolved emissions from individual stacks exhibited acceptable tracer ratios and the emission rates of metals generally agreed with the TRI estimates. This approach was later applied to two metal pollution episodes in St. Louis during in November 2001 and March 2002 and met a similar success. As NOx measurements were unavailable at those metal-production facilities, highly-specific tracer metals (i.e., Cd, Zn, and Cu) for the corresponding units were used to tune chi/Qs and their contributions were well resolved with the PMF-seeded PDRM. Opportunistically a PM2.5 excursion during a windless morning in November 2002 allowed the extraction of an in-situ profile of vehicular emissions in Baltimore. The profiles obtained by direct peak observation, windless model linear regression (WMA), PMF, and UNMIX were comparable and the WMA profile showed the best predictions for non-traffic tracers. Besides, an approach to evaluate vehicular emission factors was developed by receptor measurements under windless conditions. Using SVOC tracers, seasonal variations of traffic and other sources including coal burning, heating, biomass burning, and vegetation were investigated by PMF and in particular the November traffic profile was consistent with the WMA profile obtained earlier.
Obtention and characterization of phenolic extracts from different cocoa sources.
Ortega, Nàdia; Romero, Maria-Paz; Macià, Alba; Reguant, Jordi; Anglès, Neus; Morelló, José-Ramón; Motilva, Maria-Jose
2008-10-22
The aim of this study was to evaluate several cocoa sources to obtain a rich phenol extract for use as an ingredient in the food industry. Two types of phenolic extracts, complete and purified, from different cocoa sources (beans, nibs, liquor, and cocoa powder) were investigated. UPLC-MS/MS was used to identify and quantify the phenolic composition of the extracts, and the Folin-Ciocalteu and vanillin assays were used to determine the total phenolic and flavan-3-ol contents, respectively. The DPPH and ORAC assays were used to measure their antioxidant activity. The results of the analysis of the composition of the extracts revealed that the major fraction was procyanidins, followed by flavones and phenolic acids. From the obtained results, the nib could be considered the most interesting source for obtaining a rich phenolic cocoa extract because of its rich phenolic profile content and high antioxidant activity in comparison with the other cocoa sources.
Metabolomics study of Saw palmetto extracts based on 1H NMR spectroscopy.
de Combarieu, Eric; Martinelli, Ernesto Marco; Pace, Roberto; Sardone, Nicola
2015-04-01
Preparations containing Saw palmetto extracts are used in traditional medicine to treat benign prostatic hyperplasia. According to the European and the American Pharmacopoeias, the extract is obtained from comminuted Saw palmetto berries by a suitable extracting procedure using ethanol or supercritical carbon dioxide or a mixture of n-hexane and methylpentanes. In the present study an approach to metabolomics profiling using nuclear magnetic resonance (NMR) has been used as a finger-printing tool to assess the overall composition of the extracts. The phytochemical analysis coupled with principal component analysis (PCA) showed the same composition of the Saw palmetto extracts obtained with carbon dioxide and hexane with minor not significant differences for extracts obtained with ethanol. In fact these differences are anyhow lower than the batch-to-batch variability ascribable to the natural-occurring variability in the Saw palmetto fruits' phytochemical composition. The fingerprinting analysis combined with chemometric method, is a technique, which would provide a tool to comprehensively assess the quality control of Saw palmetto extracts. Copyright © 2015 Elsevier B.V. All rights reserved.
Accelerated fatigue testing of dentin-composite bond with continuously increasing load.
Li, Kai; Guo, Jiawen; Li, Yuping; Heo, Young Cheul; Chen, Jihua; Xin, Haitao; Fok, Alex
2017-06-01
The aim of this study was to evaluate an accelerated fatigue test method that used a continuously increasing load for testing the dentin-composite bond strength. Dentin-composite disks (ϕ5mm×2mm) made from bovine incisor roots were subjected to cyclic diametral compression with a continuously increasingly load amplitude. Two different load profiles, linear and nonlinear with respect to the number of cycles, were considered. The data were then analyzed by using a probabilistic failure model based on the Weakest-Link Theory and the classical stress-life function, before being transformed to simulate clinical data of direct restorations. All the experimental data could be well fitted with a 2-parameter Weibull function. However, a calibration was required for the effective stress amplitude to account for the difference between static and cyclic loading. Good agreement was then obtained between theory and experiments for both load profiles. The in vitro model also successfully simulated the clinical data. The method presented will allow tooth-composite interfacial fatigue parameters to be determined more efficiently. With suitable calibration, the in vitro model can also be used to assess composite systems in a more clinically relevant manner. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Karkossa, Frank; Klein, Sandra
2017-10-01
The objective of this test series was to elucidate the importance of selecting the right media composition for a biopredictive in-vitro dissolution screening of enteric-coated dosage forms. Drug release from immediate-release (IR) and enteric-coated (EC) aspirin formulations was assessed in phosphate-based and bicarbonate-based media with different pH, electrolyte composition and ionic strength. Drug release from aspirin IR tablets was unaffected by media composition. In contrast, drug release from EC aspirin formulations was affected by buffer species and ionic strength. In all media, drug release increased with increasing ionic strength, but in bicarbonate-based buffers was delayed when compared with that in phosphate-based buffers. Interestingly, the cation species in the dissolution medium had also a clear impact on drug release. Drug release profiles obtained in Blank CarbSIF, a new medium simulating pH and average ionic composition of small intestinal fluid, were different from those obtained in all other buffer compositions studied. Results from this study in which the impact of various media parameters on drug release of EC aspirin formulations was systematically screened clearly show that when developing predictive dissolution tests, it is important to simulate the ionic composition of intraluminal fluids as closely as possible. © 2017 Royal Pharmaceutical Society.
Tranchard, Pauline; Samyn, Fabienne; Duquesne, Sophie; Estèbe, Bruno; Bourbigot, Serge
2017-05-04
Thermophysical properties of a carbon-reinforced epoxy composite laminate (T700/M21 composite for aircraft structures) were evaluated using different innovative characterisation methods. Thermogravimetric Analysis (TGA), Simultaneous Thermal analysis (STA), Laser Flash analysis (LFA), and Fourier Transform Infrared (FTIR) analysis were used for measuring the thermal decomposition, the specific heat capacity, the anisotropic thermal conductivity of the composite, the heats of decomposition and the specific heat capacity of released gases. It permits to get input data to feed a three-dimensional (3D) model given the temperature profile and the mass loss obtained during well-defined fire scenarios (model presented in Part II of this paper). The measurements were optimised to get accurate data. The data also permit to create a public database on an aeronautical carbon fibre/epoxy composite for fire safety engineering.
NASA Astrophysics Data System (ADS)
Esayan, G. L.; Krivoshlykov, S. G.
1989-08-01
A method of coherent states is used to describe the process of Rayleigh scattering in a multimode graded-index waveguide with a quadratic refractive-index profile. Explicit expressions are obtained for the coefficients representing excitation of Gaussian-Hermite backscattering modes in two cases of practical importance: excitation of a waveguide by an extended noncoherent light source and selective excitation of different modes at the entry to a waveguide. An analysis is also made of the coefficients of coupling between forward and backward modes. Explicit expressions for the coefficients representing capture of backscattered radiation by a waveguide are obtained for two special cases of excitation (extended light source and zeroth mode).
Microstructure engineering of Pt-Al alloy thin films through Monte Carlo simulations
NASA Astrophysics Data System (ADS)
Harris, R. A.; Terblans, J. J.; Swart, H. C.
2014-06-01
A kinetic algorithm, based on the regular solution model, was used in conjunction with the Monte Carlo method to simulate the evolution of a micro-scaled thin film system during exposure to a high temperature environment. Pt-Al thin films were prepared via electron beam physical vapor deposition (EB-PVD) with an atomic concentration ratio of Pt63:Al37. These films were heat treated at an annealing temperature of 400 °C for 16 and 49 minutes. Scanning Auger Microscopy (SAM) (PHI 700) was used to obtain elemental maps while sputtering through the thin films. Simulations were run for the same annealing temperatures and thin-film composition. From these simulations theoretical depth profiles and simulated microstructures were obtained. These were compared to the experimentally measured depth profiles and elemental maps.
Study of the technique of stellar occultation
NASA Technical Reports Server (NTRS)
Hays, P. B.; Graves, M. E.; Roble, R. G.; Shah, A. N.
1973-01-01
The results are reported of a study of the stellar occultation technique for measuring the composition of the atmosphere. The intensity of starlight was monitored during the occultation using the Wisconsin stellar ultraviolet photometers aboard the Orbiting Astronomical Observatory (OAO-A2). A schematic diagram of an occultation is shown where the change in intensity at a given wavelength is illustrated. The vertical projection of the attenuation region is typically 60 km deep for molecular oxygen and 30 km deep for ozone. Intensity profiles obtained during various occultations were analyzed by first determining the tangential columm density of the absorbing gases, and then Abel inverting the column densities to obtain the number density profile. Errors are associated with each step in the inversion scheme and have been considered as an integral part of this study.
Analytical electron microscopy in mineralogy; exsolved phases in pyroxenes
Nord, G.L.
1982-01-01
Analytical scanning transmission electron microscopy has been successfully used to characterize the structure and composition of lamellar exsolution products in pyroxenes. At operating voltages of 100 and 200 keV, microanalytical techniques of x-ray energy analysis, convergent-beam electron diffraction, and lattice imaging have been used to chemically and structurally characterize exsolution lamellae only a few unit cells wide. Quantitative X-ray energy analysis using ratios of peak intensities has been adopted for the U.S. Geological Survey AEM in order to study the compositions of exsolved phases and changes in compositional profiles as a function of time and temperature. The quantitative analysis procedure involves 1) removal of instrument-induced background, 2) reduction of contamination, and 3) measurement of correction factors obtained from a wide range of standard compositions. The peak-ratio technique requires that the specimen thickness at the point of analysis be thin enough to make absorption corrections unnecessary (i.e., to satisfy the "thin-foil criteria"). In pyroxenes, the calculated "maximum thicknesses" range from 130 to 1400 nm for the ratios Mg/Si, Fe/Si, and Ca/Si; these "maximum thicknesses" have been contoured in pyroxene composition space as a guide during analysis. Analytical spatial resolutions of 50-100 nm have been achieved in AEM at 200 keV from the composition-profile studies, and analytical reproducibility in AEM from homogeneous pyroxene standards is ?? 1.5 mol% endmember. ?? 1982.
Samiksha, Shilpi; Sunder Raman, Ramya; Nirmalkar, Jayant; Kumar, Samresh; Sirvaiya, Rohit
2017-03-01
Size classified (PM 10 and PM 2.5 ) paved and unpaved road dust chemical source profiles, optical attenuation and potential health risk from exposure to these sources are reported in this study. A total of 45 samples from 9 paved road and 6 unpaved road sites located in and around Bhopal were re-suspended in the laboratory, collected onto filter substrates and subjected to a variety of chemical analyses. In general, road dust was enriched (compared to upper continental crustal abundance) in anthropogenic pollutants including Sb, Cu, Zn, Co, and Pb. Organic and elemental carbon (OC/EC) in PM 10 and PM 2.5 size fractions were 50-75% higher in paved road dust compared to their counterparts in unpaved road dust. Further, the results suggest that when it is not possible to include carbon fractions in source profiles, the inclusion of optical attenuation is likely to enhance the source resolution of receptor models. Additionally, profiles obtained in this study were not very similar to the US EPA SPECIATE composite profiles for PM 10 and PM 2.5 , for both sources. Specifically, the mass fractions of Si, Fe, OC, and EC were most different between SPECIATE composite profiles and Bhopal composite profiles. An estimate of health indicators for Bhopal road dust revealed that although Cr was only marginally enriched, its inhalation may pose a health risk. The estimates of potential lifetime incremental cancer risk induced by the inhalation of Cr in paved and unpaved road dust (PM 10 and PM 2.5 ) for both adults and children were higher than the baseline values of acceptable risk. These results suggest that road dust Cr induced carcinogenic risk should be further investigated. Copyright © 2016 Elsevier Ltd. All rights reserved.
Air-Coupled Ultrasonic Measurements in Composites
NASA Astrophysics Data System (ADS)
Kommareddy, V.; Peters, J. J.; Dayal, V.; Hsu, D. K.
2004-02-01
Air-coupled ultrasound is a non-contact technique and has clear advantages over water-coupled testing. Research of air-coupled ultrasonics, especially using capacitance and micromachined transducers, has been extensively reported in the literature. This paper reports our experience of applying piezoceramic air-coupled transducers for nondestructive evaluation of composites. The beam profiles of air-coupled piezoceramic transducers, with and without apodization, were mapped out. The transmission of air-coupled ultrasonic energy through composite plates of different thickness was measured experimentally; model calculation of the transmission coefficient, taking into account the frequency bandwidth of the transducer, agreed with the measurement results. The occurrence of diffraction phenomenon ("Poisson bright spot") while imaging flaws in composite laminates was investigated. The resolution of scanned images obtained with air-coupled transducers was investigated for different frequency, focusing, and apodization conditions.
NASA Astrophysics Data System (ADS)
Paramonov, G. P.; Mysin, A. V.; Babkin, R. S.
2017-10-01
The paper introduces construction of multicharge composition with separation of parts by the profile inert interval. On the basis of the previous researches, the pulse-forming process at explosion of the borehole multicharge taking into account the offered design is considered. The physical model for definition of reflected wavelet taking into account an increment of radius of cross section of a charging cavity and the expiration of detonation products is offered. A technique is developed for numerical modeling of gas-dynamic processes in a borehole with a change in the axial channel of a profile inert interval caused by a high-temperature flow of gaseous products of an explosion. The authors obtained the dependence of the change in mean pressure on the borehole wall on time for each of the parts of the multicharge. To blast a series of charges of the proposed design, taking into account optimization of the stress fields of neighboring charges, the delay interval is determined for a short-delayed explosion.
Serrato, R V; Sassaki, G L; Cruz, L M; Carlson, R W; Muszyński, A; Monteiro, R A; Pedrosa, F O; Souza, E M; Iacomini, M
2010-04-01
Bacteria from the genus Herbaspirillum are endophytes responsible for nitrogen fixation in gramineous plants of economic importance such as maize, sugarcane, sorghum, rice, and wheat. Some species are known to produce plant growth substances. In contrast, Herbaspirillum rubrisubalbicans strains are known to be mild plant pathogens. The molecular communication between the plant and the microbes might involve lipopolysaccharides present in the outer membrane of these gram-negative bacteria. Phenol-water extraction was used to obtain lipopolysaccharides from 7 strains of Herbaspirillum seropedicae (SmR1, Z67, Z78, ZA95, and M2) and H. rubrisubalbicans (M1 and M4). The electrophoretic profiles and chemical composition of the lipopolysaccharides obtained in the phenol and aqueous extracts were shown herein.
Camelo-Méndez, Gustavo A; Jara-Palacios, M José; Escudero-Gilete, M Luisa; Gordillo, Belén; Hernanz, Dolores; Paredes-López, Octavio; Vanegas-Espinoza, Pablo E; Del Villar-Martínez, Alma A; Heredia, Francisco J
2016-03-01
Roselle is a plant that accumulates anthocyanins significantly, hence its importance as food coloring and as a source of antioxidant compounds for human health. This study was aimed to determine phenolic composition and antioxidant capacity of methanolic extracts, and beverages obtained from native roselle cultivars in Mexico (Negra, Sudan, Rosa and Blanca) with different degrees of pigmentation, and to establish the color-composition relationship. Chromatographic methods were used to determine phenolic compounds: flavanols, flavonols, benzoic, hibiscus and phenolic acids as well as two main anthocyanins (cyanidin 3-sambubioside and delphinidin 3-sambubioside). The antioxidant capacity was evaluated by ABTS and FRAP assays. Tristimulus colorimetry showed to be a useful technique to determine the color-composition relationship, leading to equations that allowed to predict anthocyanin content of roselle (R > 0.84). Also, a stepwise linear discriminant analysis (SLDA) was developed in order to classify roselle cultivars. The obtained mathematical model could be an important tool to be used in colorimetric characterization of functional compounds used in food processing.
Egorov, Evgeny S; Merzlyak, Ekaterina M; Shelenkov, Andrew A; Britanova, Olga V; Sharonov, George V; Staroverov, Dmitriy B; Bolotin, Dmitriy A; Davydov, Alexey N; Barsova, Ekaterina; Lebedev, Yuriy B; Shugay, Mikhail; Chudakov, Dmitriy M
2015-06-15
Emerging high-throughput sequencing methods for the analyses of complex structure of TCR and BCR repertoires give a powerful impulse to adaptive immunity studies. However, there are still essential technical obstacles for performing a truly quantitative analysis. Specifically, it remains challenging to obtain comprehensive information on the clonal composition of small lymphocyte populations, such as Ag-specific, functional, or tissue-resident cell subsets isolated by sorting, microdissection, or fine needle aspirates. In this study, we report a robust approach based on unique molecular identifiers that allows profiling Ag receptors for several hundred to thousand lymphocytes while preserving qualitative and quantitative information on clonal composition of the sample. We also describe several general features regarding the data analysis with unique molecular identifiers that are critical for accurate counting of starting molecules in high-throughput sequencing applications. Copyright © 2015 by The American Association of Immunologists, Inc.
NASA Technical Reports Server (NTRS)
Lait, L. R.; Newman, P. A.; Schoeberl, M. R.; McGee, T.; Twigg, T.; Browell, E.; Bevilacqua, R.; Andersen, S. B.; DeBacker, H.; Benesova, A.
2004-01-01
Ozone measurements from ozonesondes, AROTAL, DIAL, and POAM III instruments during the SOLVE-2/VINTERSOL period are composited in a time-varying, flow-following quasi-conservative (PV-6) coordinate space; the resulting composites from each instrument are mapped onto the other instruments locations and times. The mapped data are then used to intercompare data from the different instruments. Overall, the four data sets are found to be in good agreement. AROTAL shows somewhat lower values below 16 km, and DIAL has a positive bias at the upper limits of its altitude range. These intercomparisons are consistent with those obtained from more conventional near-coincident profiles, where available. Although the PV-theta mapping technique entails larger uncertainties of individual profile differences compared to direct near-coincident comparisons, the ability to include much larger numbers of comparisons can make this technique advantageous.
Analysis of pultrusion processing for long fiber reinforced thermoplastic composite system
NASA Technical Reports Server (NTRS)
Tso, W.; Hou, T. H.; Tiwari, S. N.
1993-01-01
Pultrusion is one of the composite processing technology, commonly recognized as a simple and cost-effective means for the manufacturing of fiber-reinforced, resin matrix composite parts with different regular geometries. Previously, because the majority of the pultruded composite parts were made of thermosetting resin matrix, emphasis of the analysis on the process has been on the conservation of energy from various sources, such as heat conduction and the curing kinetics of the resin system. Analysis on the flow aspect of the process was almost absent in the literature for thermosetting process. With the increasing uses of thermoplastic materials, it is desirable to obtain the detailed velocity and pressure profiles inside the pultrusion die. Using a modified Darcy's law for flow through porous media, closed form analytical solutions for the velocity and pressure distributions inside the pultrusion die are obtained for the first time. This enables us to estimate the magnitude of viscous dissipation and it's effects on the pultruded parts. Pulling forces refined in the pultrusion processing are also analyzed. The analytical model derived in this study can be used to advance our knowledge and control of the pultrusion process for fiber reinforced thermoplastic composite parts.
USDA-ARS?s Scientific Manuscript database
The essential oil of air dried fruits of Prangos pabularia Lindl (Apiaceae) was obtained by hydrodistillation and its chemical profile was identified using GC-FID and GC-MS. Bicyclogermacrene (21%), (Z)-'-ocimene (19%), '-humulene (8%), '-pinene (8%) and spathulenol (6%) were the main constituents o...
NASA Astrophysics Data System (ADS)
Climent-Font, A.; Cervera, M.; Hernández, M. J.; Muñoz-Martín, A.; Piqueras, J.
2008-04-01
Rutherford backscattering spectrometry (RBS) is a well known powerful technique to obtain depth profiles of the constituent elements in a thin film deposited on a substrate made of lighter elements. In its standard use the probing beam is typically 2 MeV He. Its capabilities to obtain precise composition profiles are severely diminished when the overlaying film is made of elements lighter than the substrate. In this situation the analysis of the energy of the recoiled element from the sample in the elastic scattering event, the ERDA technique may be advantageous. For the detection of light elements it is also possible to use beams at specific energies producing elastic resonances with these light elements to be analyzed, with a much higher scattering cross sections than the Rutherford values. This technique may be called non-RBS. In this work we report on the complementary use of ERDA with a 30 MeV Cl beam and non-RBS with 1756 keV H ions to characterize thin films made of boron, carbon and nitrogen (BCN) deposited on Si substrates.
Constitutive equation on basis of electo-thermal uniaxial tension for titanium profile
NASA Astrophysics Data System (ADS)
Baosheng, Liu; Fenggong, Lv; Yuansong, Zeng; Wei, Wu; Yongjun, Wang; Fengchao, Cao
2017-10-01
Titanium alloy profiles are widely applied as airframe parts due to its excellent mechanical properties and high compatibility of electrical potential with resin composite material. The electrical assisted forming is recognized as the effective approach to improve plasticity of titanium alloy profile. In this work, the electo-thermal uniaxial tension was performed to investigate the mechanical properties. The experiment results show that, the stress-strain curves increases sharply to the peak and declines quickly, exhibiting no stable deformation occurring. On basis of the obtained curves, a constitutive equation was established with consideration of the characteristic of self resistance heating, and the microstructure evolution was predicted. A comparison of the calculated stress-strain curves with the experimental ones was conducted, showing a reasonable agreement.
Sol-gel Derived Warfarin - Silica Composites for Controlled Drug Release.
Dolinina, Ekaterina S; Parfenyuk, Elena V
2017-01-01
Warfarin, commonly used anticoagulant in clinic, has serious shortcomings due to its unsatisfactory pharmacodynamics. One of the efficient ways for the improvement of pharmacological and consumer properties of drugs is the development of optimal drug delivery systems. The aim of this work is to synthesize novel warfarin - silica composites and to study in vitro the drug release kinetics to obtain the composites with controlled release. The composites of warfarin with unmodified (UMS) and mercaptopropyl modified silica (MPMS) were synthesized by sol-gel method. The composite formation was confirmed by FTIR spectra. The concentrations of warfarin released to media with pH 1.6, 6.8 and 7.4 were measured using UV spectroscopy. The drug release profiles from the solid composites were described by a series of kinetic models which includes zero order kinetics, first order kinetics, the modified Korsmeyer-Peppas model and Hixson-Crowell model. The synthesized sol-gel composites have different kinetic behavior in the studied media. In contrast to the warfarin composite with unmodified silica, the drug release from the composite with mercaptopropyl modified silica follows zero order kinetics for 24 h irrespective to the release medium pH due to mixed mechanism (duffusion + degradation and/or disintegration of silica matrix). The obtained results showed that warfarin - silica sol-gel composites have a potential application for the development of novel oral formulation of the drug with controlled delivery. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Effect of asymmetric concentration profile on thermal conductivity in Ge/SiGe superlattices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hahn, Konstanze R., E-mail: konstanze.hahn@dsf.unica.it; Cecchi, Stefano; Colombo, Luciano
2016-05-16
The effect of the chemical composition in Si/Ge-based superlattices on their thermal conductivity has been investigated using molecular dynamics simulations. Simulation cells of Ge/SiGe superlattices have been generated with different concentration profiles such that the Si concentration follows a step-like, a tooth-saw, a Gaussian, and a gamma-type function in direction of the heat flux. The step-like and tooth-saw profiles mimic ideally sharp interfaces, whereas Gaussian and gamma-type profiles are smooth functions imitating atomic diffusion at the interface as obtained experimentally. Symmetry effects have been investigated comparing the symmetric profiles of the step-like and the Gaussian function to the asymmetric profilesmore » of the tooth-saw and the gamma-type function. At longer sample length and similar degree of interdiffusion, the thermal conductivity is found to be lower in asymmetric profiles. Furthermore, it is found that with smooth concentration profiles where atomic diffusion at the interface takes place the thermal conductivity is higher compared to systems with atomically sharp concentration profiles.« less
Tranchard, Pauline; Samyn, Fabienne; Duquesne, Sophie; Estèbe, Bruno; Bourbigot, Serge
2017-01-01
Thermophysical properties of a carbon-reinforced epoxy composite laminate (T700/M21 composite for aircraft structures) were evaluated using different innovative characterisation methods. Thermogravimetric Analysis (TGA), Simultaneous Thermal analysis (STA), Laser Flash analysis (LFA), and Fourier Transform Infrared (FTIR) analysis were used for measuring the thermal decomposition, the specific heat capacity, the anisotropic thermal conductivity of the composite, the heats of decomposition and the specific heat capacity of released gases. It permits to get input data to feed a three-dimensional (3D) model given the temperature profile and the mass loss obtained during well-defined fire scenarios (model presented in Part II of this paper). The measurements were optimised to get accurate data. The data also permit to create a public database on an aeronautical carbon fibre/epoxy composite for fire safety engineering. PMID:28772854
Microstructure and hardness performance of AA6061 aluminium composite using friction stir processing
NASA Astrophysics Data System (ADS)
Marini, C. D.; Fatchurrohman, N.
2018-04-01
Rice husk ash (RHA) is an industrial waste that has become a potential reinforced material for aluminium matrix composite (AMCs) due to low cost and abundantly available resources. Friction stir processing (FSP) has been introduced as a method to modify surface properties of the metal and alloy including theirs composite as well. The present work reports the production and characterization of AA6061 and AA6061/5 vol% RHA using FSP using parameters rotation speed 1000 rpm and traversed speed 25 mm/min. The microstructure was studied using optical microscopy (OM). A homogenous dispersion of RHA particles was obtained in the composite. No agglomeration or segregation was observed. The produced composite exhibited a fine grain structure. An improvement in hardness profile was observed as AA6061/5 vol% RHA improves in hardness compared to FSPed of AA6061 without reinforcement.
NASA Astrophysics Data System (ADS)
Angeliu, Thomas M.; Was, Gary S.
1990-08-01
Grain boundary composition and carbide composition and structure were characterized for various microstructures of controlled purity alloy 690. Heat treatments produced varying degrees of grain boundary chromium depletion and precipitate distributions which were characterized via scanning transmission electron microscopy (STEM). Convergent beam electron diffraction revealed that the dominant carbide is M23C6, and energy dispersive X-ray analysis (EDAX) determined that the metallic content was about 90 at. pct chromium. A discontinuous precipitation reaction was observed and is attributed to a high degree of carbon supersaturation. Grain boundary composition measurements confirm that chromium depletion is controlled by volume diffusion of chromium to chromium-rich grain boundary carbides in the temperature range of 873 to 1073 K. Grain boundary chromium levels as low as 18.8 at. pct were obtained by thermal treatment at 873 K for 250 hours and 973 K for 1 hour. A thermodynamic and kinetic model developed for alloy 600 was modified to describe the development of the chromium depletion profile in alloy 690 during thermal treatment. Experimentally measured chromium profiles agree well with the model results for the dependence of the chromium depletion zone width and depth on various input parameters. The establishment of the model for alloy 690 allows the chromium depletion zone width and depth to be computed as a function of alloy composition, grain size, and temperature. The chromium depletion profiles and the precipitate structure and composition of controlled purity 690 are compared to those of controlled purity 600. A thermodynamic analysis of the carbide stability indicates that other factors, such as favorable orientation relationships, play an important role in controlling the precipitation of Cr23C6 in nickel-base alloys.
Viuda-Martos, Manuel; El Gendy, Abd El-Nasser G S; Sendra, Esther; Fernández-López, Juana; Abd El Razik, K A; Omer, Elsayed A; Pérez-Alvarez, Jose A
2010-08-25
The aim of this work was to (i) determine the chemical composition of the essential oils of six spices widely cultivated in Egypt (Origanum syriacum, Majorana hortensis, Rosmarinus officinalis, Cymbopogon citratus, Thymus vulgaris, and Artemisia annua); (ii) determine the antioxidant activity of the Egyptian essential oils by means of five different antioxidant tests; and (iii) determine the effectiveness of these essential oils on the inhibition of Listeria innocua CECT 910. There is a great variability in the chemical composition of essential oils obtained from the six Egyptian aromatic plants. Overall, thyme (highest percentage of inhibition of DPPH radical: 89.40%) and oregano (highest percentage of inhibition of TBARS: 85.79) essential oils presented the best antioxidant profiles, whereas marjoram, lemongrass, and artemisia were highly effective in metal chelating but had a pro-oxidative behavior by Rancimat induction test. Lemongrass essential oil showed the highest antibacterial activity against L. innocua with an inhibition zone of 49.00 mm, followed in effectiveness by thyme, marjoram, and oregano.
Computer aided design of extrusion forming tools for complex geometry profiles
NASA Astrophysics Data System (ADS)
Goncalves, Nelson Daniel Ferreira
In the profile extrusion, the experience of the die designer is crucial for obtaining good results. In industry, it is quite usual the need of several experimental trials for a specific extrusion die before a balanced flow distribution is obtained. This experimental based trial-and-error procedure is time and money consuming, but, it works, and most of the profile extrusion companies rely on such method. However, the competition is forcing the industry to look for more effective procedures and the design of profile extrusion dies is not an exception. For this purpose, computer aided design seems to be a good route. Nowadays, the available computational rheology numerical codes allow the simulation of complex fluid flows. This permits the die designer to evaluate and to optimize the flow channel, without the need to have a physical die and to perform real extrusion trials. In this work, a finite volume based numerical code was developed, for the simulation of non-Newtonian (inelastic) fluid and non-isothermal flows using unstructured meshes. The developed code is able to model the forming and cooling stages of profile extrusion, and can be used to aid the design of forming tools used in the production of complex profiles. For the code verification three benchmark problems were tested: flow between parallel plates, flow around a cylinder, and the lid driven cavity flow. The code was employed to design two extrusion dies to produce complex cross section profiles: a medical catheter die and a wood plastic composite profile for decking applications. The last was experimentally validated. Simple extrusion dies used to produced L and T shaped profiles were studied in detail, allowing a better understanding of the effect of the main geometry parameters on the flow distribution. To model the cooling stage a new implicit formulation was devised, which allowed the achievement of better convergence rates and thus the reduction of the computation times. Having in mind the solution of large dimension problems, the code was parallelized using graphics processing units (GPUs). Speedups of ten times could be obtained, drastically decreasing the time required to obtain results.
Predicting protein-binding regions in RNA using nucleotide profiles and compositions.
Choi, Daesik; Park, Byungkyu; Chae, Hanju; Lee, Wook; Han, Kyungsook
2017-03-14
Motivated by the increased amount of data on protein-RNA interactions and the availability of complete genome sequences of several organisms, many computational methods have been proposed to predict binding sites in protein-RNA interactions. However, most computational methods are limited to finding RNA-binding sites in proteins instead of protein-binding sites in RNAs. Predicting protein-binding sites in RNA is more challenging than predicting RNA-binding sites in proteins. Recent computational methods for finding protein-binding sites in RNAs have several drawbacks for practical use. We developed a new support vector machine (SVM) model for predicting protein-binding regions in mRNA sequences. The model uses sequence profiles constructed from log-odds scores of mono- and di-nucleotides and nucleotide compositions. The model was evaluated by standard 10-fold cross validation, leave-one-protein-out (LOPO) cross validation and independent testing. Since actual mRNA sequences have more non-binding regions than protein-binding regions, we tested the model on several datasets with different ratios of protein-binding regions to non-binding regions. The best performance of the model was obtained in a balanced dataset of positive and negative instances. 10-fold cross validation with a balanced dataset achieved a sensitivity of 91.6%, a specificity of 92.4%, an accuracy of 92.0%, a positive predictive value (PPV) of 91.7%, a negative predictive value (NPV) of 92.3% and a Matthews correlation coefficient (MCC) of 0.840. LOPO cross validation showed a lower performance than the 10-fold cross validation, but the performance remains high (87.6% accuracy and 0.752 MCC). In testing the model on independent datasets, it achieved an accuracy of 82.2% and an MCC of 0.656. Testing of our model and other state-of-the-art methods on a same dataset showed that our model is better than the others. Sequence profiles of log-odds scores of mono- and di-nucleotides were much more powerful features than nucleotide compositions in finding protein-binding regions in RNA sequences. But, a slight performance gain was obtained when using the sequence profiles along with nucleotide compositions. These are preliminary results of ongoing research, but demonstrate the potential of our approach as a powerful predictor of protein-binding regions in RNA. The program and supporting data are available at http://bclab.inha.ac.kr/RBPbinding .
NASA Technical Reports Server (NTRS)
Miller, James G.
1997-01-01
In this Progress Report, we describe our recent developments of advanced ultrasonic nondestructive evaluation methods applied to the characterization of anisotropic materials. We present images obtained from experimental measurements of ultrasonic diffraction patterns for a thin woven composite in an immersion setup. In addition, we compare apparent signal loss measurements of the thin woven composite for phase-sensitive and phase-insensitive detection methods. All images of diffraction patterns have been included on the accompanying CD-ROM in the Adobe(Trademark) Portable Document Format (PDF). Due to the extensive amount of data, however, hardcopies of only a small representative selection of the images are included within the printed report. This Progress Report presents experimental results that support successful implementation of single element as well as one and two-dimensional ultrasonic array technologies for the inspection of textile composite structures. In our previous reports, we have addressed issues regarding beam profiles of ultrasonic pressure fields transmitted through a water reference path and transmitted through a thin woven composite sample path. Furthermore, we presented experimental results of the effect of a thin woven composite on the magnitude of an insonifying ultrasonic pressure field. In addition to the study of ultrasonic beam profiles, we consider issues relevant to the application of single-element, one-dimensional, and two-dimensional array technologies towards probing the mechanical properties of advanced engineering composites and structures. We provide comparisons between phase-sensitive and phase-insensitive detection methods for determination of textile composite structure parameters. We also compare phase-sensitive and phase-insensitive - - ---- ----- apparent signal loss measurements in an effort to study the phenomenon of phase cancellation at the face of a finite-aperture single-element receiver. Furthermore, in this Progress Report we extend our work on ultrasonic beam profile issues through investigation of the phase fronts of the pressure field. In Section H of this Progress Report we briefly describe the experimental arrangement and methods for data acquisition of the ultrasonic diffraction patterns upon transmission through a thin woven composite. Section III details the analysis of the experimental data followed by the experimental results in Section IV. Finally, a discussion of the observations and conclusions is found in Section V.
Rodrigues, N F; Kästle, J; Coutinho, T J D; Amorim, A T; Campos, G B; Santos, V M; Marques, L M; Timenetsky, J; de Farias, S T
2015-06-12
The microbial community of the reproductive appara-tus, when known, can provide information about the health of the host. Metagenomics has been used to characterize and obtain genetic infor-mation about microbial communities in various environments and can relate certain diseases with changes in this community composition. In this study, samples of vaginal surface mucosal secretions were col-lected from five healthy cows and five cows that showed symptoms of reproductive disorders. Following high-throughput sequencing of the isolated microbial DNA, data were processed using the Mothur soft-ware to remove low-quality sequences and chimeras, and released to the Ribosomal Database Project for classification of operational taxo-nomic units (OTUs). Local BLASTn was performed and results were loaded into the MEGAN program for viewing profiles and taxonomic microbial attributes. The control profile comprised a total of 15 taxa, with Bacteroides, Enterobacteriaceae, and Victivallis comprising the highest representation of OTUs; the reproductive disorder-positive profile comprised 68 taxa, with Bacteroides, Enterobacteriaceae, His-tophilus, Victivallis, Alistipes, and Coriobacteriaceae being the taxa with the most OTU representation. A change was observed in both the community composition as well as in the microbial attributes of the profiles, suggesting that a relationship might exist between the patho-gen and representative taxa, reflecting the production of metabolites to disease progression.
Brundige, Dottie R.; Maga, Elizabeth A.; Klasing, Kirk C.
2009-01-01
Nutrition, bacterial composition of the gastrointestinal tract, and general health status can all influence the metabolic profile of an organism. We previously demonstrated that feeding pasteurized transgenic goats’ milk expressing human lysozyme (hLZ) can positively impact intestinal morphology and modulate intestinal microbiota composition in young pigs. The objective of this study was to further examine the effect of consuming hLZ-containing milk on young pigs by profiling serum metabolites. Pigs were placed into two groups and fed a diet of solid food and either control (non-transgenic) goats’ milk or milk from hLZ-transgenic goats for 6 weeks. Serum samples were collected at the end of the feeding period and global metabolite profiling was performed. For a total of 225 metabolites (160 known, 65 unknown) semi-quantitative data was obtained. Levels of 18 known and 4 unknown metabolites differed significantly between the two groups with the direction of change in 13 of the 18 known metabolites being almost entirely congruent with improved health status, particularly in terms of the gastrointestinal tract health and immune response, with the effects of the other five being neutral or unknown. These results further support our hypothesis that consumption of hLZ-containing milk is beneficial to health. PMID:19847666
Brundige, Dottie R; Maga, Elizabeth A; Klasing, Kirk C; Murray, James D
2010-08-01
Nutrition, bacterial composition of the gastrointestinal tract, and general health status can all influence the metabolic profile of an organism. We previously demonstrated that feeding pasteurized transgenic goats' milk expressing human lysozyme (hLZ) can positively impact intestinal morphology and modulate intestinal microbiota composition in young pigs. The objective of this study was to further examine the effect of consuming hLZ-containing milk on young pigs by profiling serum metabolites. Pigs were placed into two groups and fed a diet of solid food and either control (non-transgenic) goats' milk or milk from hLZ-transgenic goats for 6 weeks. Serum samples were collected at the end of the feeding period and global metabolite profiling was performed. For a total of 225 metabolites (160 known, 65 unknown) semi-quantitative data was obtained. Levels of 18 known and 4 unknown metabolites differed significantly between the two groups with the direction of change in 13 of the 18 known metabolites being almost entirely congruent with improved health status, particularly in terms of the gastrointestinal tract health and immune response, with the effects of the other five being neutral or unknown. These results further support our hypothesis that consumption of hLZ-containing milk is beneficial to health.
Modulation of antimicrobial metabolites production by the fungus Aspergillus parasiticus
Bracarense, Adriana A.P.; Takahashi, Jacqueline A.
2014-01-01
Biosynthesis of active secondary metabolites by fungi occurs as a specific response to the different growing environments. Changes in this environment alter the chemical and biological profiles leading to metabolites diversification and consequently to novel pharmacological applications. In this work, it was studied the influence of three parameters (fermentation length, medium composition and aeration) in the biosyntheses of antimicrobial metabolites by the fungus Aspergillus parasiticus in 10 distinct fermentation periods. Metabolism modulation in two culturing media, CYA and YES was evaluated by a 22 full factorial planning (ANOVA) and on a 23 factorial planning, role of aeration, medium composition and carbohydrate concentration were also evaluated. In overall, 120 different extracts were prepared, their HPLC profiles were obtained and the antimicrobial activity against A. flavus, C. albicans, E. coli and S. aureus of all extracts was evaluated by microdilution bioassay. Yield of kojic acid, a fine chemical produced by the fungus A. parasiticus was determined in all extracts. Statistical analyses pointed thirteen conditions able to modulate the production of bioactive metabolites by A. parasiticus. Effect of carbon source in metabolites diversification was significant as shown by the changes in the HPLC profiles of the extracts. Most of the extracts presented inhibition rates higher than that of kojic acid as for the extract obtained after 6 days of fermentation in YES medium under stirring. Kojic acid was not the only metabolite responsible for the activity since some highly active extracts showed to possess low amounts of this compound, as determined by HPLC. PMID:24948950
Vénica, Claudia I; Wolf, Irma V; Bergamini, Carina V; Perotti, María C
2016-12-01
Different types of reduced-lactose yogurt, obtained by lactose hydrolysis using β-galactosidase enzyme, are commercially available. The breakdown of lactose modifies the carbohydrate profile, including the production of prebiotic galacto-oligosaccharides (GOS), which could affect the survival and activity of starter and probiotic cultures and the parameters of yogurt quality. The extension of these changes is dependent on the yogurt matrix composition. This study aimed to evaluate the influence of lactose hydrolysis on GOS, lactose, volatile profile and physicochemical parameters of different yogurt varieties during storage. The presence of β-galactosidase enzyme did not affect either the global composition or the survival of cultures. Overall, the hydrolyzed products had lower acidity than traditional ones. GOS were found at similar levels in fresh hydrolyzed yogurts, whereas in traditional yogurts they were not detected. The proportion of ketones, acids and aldehydes seems to be more dependent on yogurt variety than on addition of the enzyme. Likewise, the storage period affected the volatile fraction to different degree; the increase in acid compounds was more pronounced in hydrolyzed than in traditional yogurts. This work shows that it is possible to obtain different varieties of reduced-lactose yogurt, some of them with additional benefits to health such as reduced fat, reduced calories, added with probiotic/inulin and enriched in GOS, with similar characteristics to traditional products. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
NASA Astrophysics Data System (ADS)
Esteban, J. J.; Tubía, J. M.; Cuevas, J.; Gil Ibarguchi, J. I.
2012-04-01
Garnet porphyroblast textures and compositions, coupled to those of accompanying phases, are one of the most useful tools to determine the change of P-T conditions during metamorphism. This is currently done quantitatively through the use of conventional thermobarometry and pseudosection analysis, whose validity is conditioned by assumptions on the chemical mineral equilibrium (e.g. Spear, 1993). In the case of metapelites, the classic approach involves the use of core to rim compositions in zoned garnets and coexisting phases by electron microprobe analysis. Nonetheless, it is a high time consuming technique. As an alternative, we test the use of back-scattered electron (BSE) images and semi-quantitative energy-dispersive X-ray spectroscopy profiles obtained by scanning eletron microscope (SEM-EDX) to distinguish between clockwise and counterclockwise P-T paths. We applied these SEM techniques in samples of micaschist from the Yunquera Unit (Internal Zone, Betic Cordilleras, Spain) (Dürr, 1969). BSE images were obtained on selected areas covering the texturally and mineralogically most significant garnet-bearing portions, whereas semiquantitative profiles for Ca, Fe, Mg and Mn were obtained by means of EDX counting. Different types of chemical profiles were observed: (a) normal (growth) continuous zoning, (b) discontinuous, and (c) reverse continuous zoning. The patterns of chemical profiles are in agreement with changes in internal microstructures and density of inclusion. Two types of continuous growth zoning were identified in subspherical garnets bearing internal foliations. XMn and XFe ratios show the classical bell-shaped geometry while XCa increases in some cases and decreases in others towards rims. Discontinuous garnet profiles are typical of multistage garnet growth, which is outlined by the occurrence of alternating low- and high-inclusion density areas. Garnets with low-inclusion density cores show homogeneous core composition with an abrupt change towards the rims marked by a rapid increase in XCa and decrease in XFe and XMg ratios. Garnets with high-density inclusion cores depict XCa ratios at core similar to the previous ones and a sudden decrease towards the rims, whereas XFe and XMg continuously increase from core to rim. Reverse continuous profiles are typical of small idiomorphic garnets either enclosed or surrounding large muscovite porphyroblasts. These garnets show an increase in XMn and a decrease in XFe and XMg ratios from core to rim with minor variations in Ca. Taken as a whole, the chemical profiles reveal a generalized increase in Fe# [Fe/(Fe+Mg)] towards the rims that would attest to a temperature increase during the growth of the garnets. In addition, continuous and discontinuous variations in XCa ratios in large garnets suggest prograde garnet growth following a clockwise P-T path evolution, that is, a pressure increase followed by decrease under continuously increasing T conditions. As a conclusion, it is suggested that a method based mainly on the acquisition of BSE images and semiquantitative chemical profiles on selected minerals, and their interpretation using conventional thermo-barometric reasoning would be useful in the establishment of relative P-T paths that might help to save time and better identify the areas of interest for later detailed electron microprobe studies.
An analysis of a charring ablator with thermal nonequilibrium, chemical kinetics, and mass transfer
NASA Technical Reports Server (NTRS)
Clark, R. K.
1973-01-01
The differential equations governing the transient response of a one-dimensional ablative thermal protection system are presented for thermal nonequilibrium between the pyrolysis gases and the char layer and with finite rate chemical reactions occurring. The system consists of three layers (the char layer, the uncharred layer, and an optical insulation layer) with concentrated heat sinks at the back surface and between the second and third layers. The equations are solved numerically by using a modified implicit finite difference scheme to obtain solutions for the thickness of the charred and uncharred layers, surface recession and pyrolysis rates, solid temperatures, porosity profiles, and profiles of pyrolysis-gas temperature, pressure, composition, and flow rate. Good agreement is obtained between numerical results and exact solutions for a number of simplified cases. The complete numerical analysis is used to obtain solutions for an ablative system subjected to a constant heating environment. Effects of thermal, chemical, and mass transfer processes are shown.
Kauffman, S.J.; Herman, J.S.; Jones, B.F.
1998-01-01
The influence of clay units on ground-water composition was investigated in a heterogeneous carbonate aquifer system of Miocene age in southwest Florida, known as the Intermediate aquifer system. Regionally, the ground water is recharged inland, flows laterally and to greater depths in the aquifer systems, and is discharged vertically upward at the saltwater interface along the coast. A depth profile of water composition was obtained by sampling ground water from discrete intervals within the permeable carbonate units during coring and by squeezing pore water from a core of the less-permeable clay layers. A normative salt analysis of solute compositions in the water indicated a marine origin for both types of water and an evolutionary pathway for the clay water that involves clay diagenesis. The chemical composition of the ground water in the carbonate bedrock is significantly different from that of the pore water in the clay layers. Dissolution of clays and opaline silica results in high silica concentrations relative to water in other parts of the Intermediate aquifer system. Water enriched in chloride relative to the overlying and underlying ground water recharges the aquifer inland where the confining clay layer is absent, and it dissolves carbonate and silicate minerals and reacts with clays along its flow path, eventually reaching this coastal site and resulting in the high chloride and silica concentrations observed in the middle part of the Intermediate aquifer system. Reaction-path modeling suggests that the recharging surficial water mixes with sulfate-rich water upwelling from the Upper Floridan aquifer, and carbonate mineral dissolution and precipitation, weathering and exchange reactions, clay mineral diagenesis, clay and silica dissolution, organic carbon oxidation, and iron and sulfate reduction result in the observed water compositions.A study was conducted to clarify the influence of clay units on ground-water composition in a heterogeneous carbonate aquifer system of Miocene age in southwest Florida. A depth profile of water composition was obtained by sampling ground water from discrete intervals within the permeable carbonate units during coring and by squeezing pore water from a core of the less-permeable clay layers. A normative salt analysis of solute compositions in the water indicated a marine origin for both types of water and an evolutionary pathway for the clay water that involves clay diagenesis. The factors influencing water compositions were determined.
Body composition and somatotypes of male Zimbabwean Premier League football referees.
Banda, Morris; Grobbelaar, Heinrich W; Terblanche, Elmarie
2018-04-20
Elite athletes need to optimise their body composition to deliver world class performances and this argument could be extended to elite referees as well. Unfortunately, there is a scarcity of body composition information among football referees. The aim of the study was to determine and compare the body composition and somatotypes of male football referees and assistant referees who officiated in the 2013 Zimbabwe Premier Football League. Forty-one participants (21 referees, 20 assistant referees; 8 FIFA, 33 ZIFA licenced referees) with a mean age of 34.89 ± 5.13 years took part. They had on average 10.85 ± 3.85 years of refereeing experience. The ISAK restricted anthropometric profile was used to measure body mass, height, skinfolds, girths and bone breadths, from which body mass index (BMI), waist-to-hip ratio (WHR), percentage body fat and somatotype were calculated. The referees were significantly taller than the assistant referees. The FIFA referees had moderately more desirable anthropometric profiles than the ZIFA referees. With a mean somatotype of 2.62-4.65-2.65, the total sample could be classified as balanced mesomorphs. They had lower BMI and body fat percentages than that observed among referees from other nationalities in the available literature. The results add to the paucity of information on the body composition of football officials. Referees aiming to excel at higher levels need to obtain and maintain an ideal body composition since elite level football is intense and requires high fitness levels.
Ishikawa, Junko; Shimotoyodome, Yoshie; Ito, Shotaro; Miyauchi, Yuki; Fujimura, Tsutomu; Kitahara, Takashi; Hase, Tadashi
2013-03-01
The objective of this study was to clarify variations of the ceramide (CER) profile in human stratum corneum (SC) in different seasons and in different regions of the body and to estimate the contributions of CERs to the SC barrier and water-holding functions. Based on the information that there are great variations of SC functions among body sites, we compared the CER profiles obtained from ten different anatomical sites in healthy Japanese males in four seasons. Not only the physiological parameters of skin but also the CER profile showed body region and seasonal variations. The total CER level, the CER composition and the C34-CER[NS] species displayed strong correlations with the values of transepidermal water loss and capacitance throughout the body. Especially in the cheek, a strong correlation between the capacitance and the CER profile was observed. There were seasonal variations of the CER profile in the lip, upper arm and palm. Our results indicate that regional and seasonal variations of the CER profile may contribute to SC functions.
Equation of State of Aluminum-Iron Oxide-Epoxy Composite
2007-07-01
which case shock velocities were measured in the samples and aluminum, copper, or polymethyl methacrylate PMMA donor material, using piezoelectric pins...which piezoelectric polyvinylidene fluoride PVDF stress gauges were used to measure the input and propagated stress wave profiles in the sample and...instrumented with Bauer piezoelectric polyvinylidene fluoride PVDF stress gauges6 obtained from Ktech Corporation, Albuquerque, NM. The gauges were mounted on
Including granulometric sediment coastal data composition into the Black Sea GIS
NASA Astrophysics Data System (ADS)
Zhuk, Elena; Khaliulin, Alexey; Krylenko, Marina; Krylenko, Viacheslav; Zodiatis, George; Nikolaidis, Marios; Nikolaidis, Andreas
2017-09-01
The module structure of the Black Sea GIS allows the increasing of its functionality, including new data types and defining new procedures accessing them, their visualization and integration with existing data by their conjoint processing and representation. The Black Sea GIS is released as free software; Mapserver is used as a mapping service; MySQL DBMS works with relational data. A new additional feature provided, is the ability of including coastal data obtained in SB SIO RAS. The data represent granulometric composition of the Anapa bay-bar sediments. The Anapa bay-bar is an accumulative sand form (about 50 km long) located on the northwest Russian Black Sea coast. The entire bay-bar and especially its southern part with sand beaches 50-200 m wide is intensively used in recreation. This work is based on the results of field studies of 2010-2014 in the southern part of the Anapa bay-bar researched by scientists of the Shirshov Institute of Oceanology RAS. Since the shore under consideration has no clearly pronounced reference points, "virtual" points located within 1 km distance from each other were selected. Transversal profiles cross these points. The granulometric composition was studied along with 45 profiles. The samples taken in every profile were from the most characteristic morphological parts of the beach. In this study we used shoreline zone samples. Twenty one granule fractions (mm) were separated in the laboratory. The module which processes coastal data allows to select coastal data based on territory/region and granulometric sediment composition. Also, it allows to visualize coastal maps with user-selected features combined with other GIS data.
Ulshina, D V; Kovalev, D A; Zhirov, A M; Zharinova, N V; Khudoleev, A A; Kogotkova, O I; Efremenko, V I; Evchenko, N I; Kulichenko, A N
2016-01-01
Carry out comparative analysis using time-of-flight mass-spectrometry with matrix laser desorption/ionization (MALDI-TOF MS) of protein profiles of brucellosis causative agents (Brucella melitensis Rev-1 and Brucella abortus 19BA), cultivated in various nutrient media: Albimi agar, brucellagar and erythrit-agar. Vaccine,strains: Brucella melitensis Rev-1 and Brucella abortus 19BA. Protein profiling in linear mode on Microflex "Bruker Daltonics" MALDI-TOF mass-spectrometer. A number of characteristic features of brucella mass-spectra was detected: in particular, preservation of the total qualitative composition of protein profiles of cultures and significant differences in the intensity of separate peaks depending on the nutrient medium used. Based on the analysis of the data obtained, use of Albimi agar as the nutrient medium for preparation of brucella culture samples for mass-spectrometric analysis was shown to be optimal.
NASA Technical Reports Server (NTRS)
Brainard, W. A.; Wheeler, D. R.
1977-01-01
Radiofrequency sputtered coatings of titanium carbide, molybdenum carbide and titanium boride were tested as wear resistant coatings on stainless steel in a pin on disk apparatus. X-ray photoelectron spectroscopy (XPS) was used to analyze the sputtered films with regard to both bulk and interface composition in order to obtain maximum film performance. Significant improvements in friction behavior were obtained when properly biased films were deposited on deliberately preoxidized substrates. XPS depth profile data showed thick graded interfaces for bias deposited films even when adherence was poor. The addition of 10 percent hydrogen to the sputtering gas produced coatings with thin poorly adherent interfaces. Results suggest that some of the common practices in the field of sputtering may be detrimental to achieving maximum adherence and optimum composition for these refractory compounds.
Sakurai, Toshihiro; Aoki, Motohide; Ju, Xiaohui; Ueda, Tatsuya; Nakamura, Yasunori; Fujiwara, Shoko; Umemura, Tomonari; Tsuzuki, Mikio; Minoda, Ayumi
2016-01-01
The unicellular red alga Galdieria sulphuraria grows efficiently and produces a large amount of biomass in acidic conditions at high temperatures. It has great potential to produce biofuels and other beneficial compounds without becoming contaminated with other organisms. In G. sulphuraria, biomass measurements and glycogen and lipid analyses demonstrated that the amounts and compositions of glycogen and lipids differed when cells were grown under autotrophic, mixotrophic, and heterotrophic conditions. Maximum biomass production was obtained in the mixotrophic culture. High amounts of glycogen were obtained in the mixotrophic cultures, while the amounts of neutral lipids were similar between mixotrophic and heterotrophic cultures. The amounts of neutral lipids were highest in red algae, including thermophiles. Glycogen structure and fatty acids compositions largely depended on the growth conditions. Copyright © 2015. Published by Elsevier Ltd.
Morphological characteristics of Street Workout practitioners.
Sanchez-Martinez, Javier; Plaza, Paula; Araneda, Alberto; Sánchez, Patricio; Almagiâ, Atilio
2017-02-01
The determination of the morphological characteristics of the most popular sports has allowed the evaluation and comparison between athletes, which has helped to improve their performance. The Street Workout is an emerging sport based on calisthenics, which recently has become popular. Despite its popularization, neither the morphologic profile nor the morphologic characteristics of Street Workout athletes has been determined. Determine the profile and morphological characteristics of Street-Workout athletes, through anthropometry. Fourteen athletes (22.7 ± 3.26 years) were recruited from the National Calisthenics Tournament 2015 in Chile. The athletes were evaluated following the protocol of the International Society for the Advancement of Kinanthropometry to determine the somatotype, body composition, as well as indices of body composition such as body mass index, waist to hip ratio, waist to height ratio, fat/muscle mass and muscle/bone mass indexes. Street Workout practitioners presented a balanced-mesomorphic somatotype, a low fat mass and a high muscular development, with upper arms and trunk predominance. Regarding body composition indices, the values obtained allow us to classify them as a low-risk population of chronic non-communicable diseases. The present study sets a first antecedent of the morphological characteristics of Street Workout, determining that the Street Workout athletes presented balanced-mesomorphic somatotype and were classified as a healthy and athletic sample by their body composition indexes.
Water-cooled probe technique for the study of freeze lining formation
NASA Astrophysics Data System (ADS)
Verscheure, Karel; Campforts, Mieke; Verhaeghe, Frederik; Boydens, Eddy; Blanpain, Bart; Wollants, Patrick; van Camp, Maurits
2006-12-01
Furnace protection by water-cooled freeze linings becomes increasingly important as the metal producing industry attempts to achieve higher process intensities. Systematic investigations of the growth and the resulting microstructure and compositional profile of freeze linings are necessary to understand the behavior of freeze linings, their relation with the industrial process, and their interaction with the wall cooling system. We have developed a technique based on the submergence of a water-cooled probe into a liquid slag bath. Freeze linings of two industrial nonferrous slags have been produced using this technique and their growth, microstructural, and compositional profiles as a function of submergence time were determined. Thermodynamic equilibrium for the investigated slag systems was calculated and compared with the observed microstructures. The freeze linings form in approximately 15 minutes. Close to the water cooling, the freeze linings are predominantly amorphous in structure. With increasing distance from the water cooling, the proportion of crystalline phases increases and bath material is entrapped in the microstructure. Cellular crystals are observed close to the bath. The freeze linings exhibit an approximate homogeneous composition. The results demonstrate that the technique is a successful tool in obtaining information on the growth, microstructure, and composition of freeze linings in industrial water-cooled furnaces.
La Nasa, Jacopo; Zanaboni, Marco; Uldanck, Daniele; Degano, Ilaria; Modugno, Francesca; Kutzke, Hartmut; Tveit, Eva Storevik; Topalova-Casadiego, Biljana; Colombini, Maria Perla
2015-10-08
Modern oil paints, introduced at the beginning of the 20th century, differ from those classically used in antiquity in their chemical and compositional features. The main ingredients were still traditional drying oils, often used in mixtures with less expensive oils and added with several classes of additives. Consequently, detailed lipid profiling, together with the study of lipid degradation processes, is essential for the knowledge and the conservation of paint materials used in modern and contemporary art. A multi-analytical approach based on mass spectrometry was used for the study of original paint materials from Munch's atelier, owned by the Munch Museum in Oslo. The results obtained in the analysis of paint tubes were compared with those obtained by characterizing a paint sample collected from one of the artist's sketches for the decoration of the Festival Hall of the University of Oslo (1909-1916). Py-GC/MS was used as screening method to evaluate the presence of lipid, proteic or polysaccaridic materials. GC/MS after hydrolysis and derivatization allowed us to determine the fatty acid profile of the paint tubes, and to evaluate the molecular changes associated to curing and ageing. The determination of the fatty acid profile is not conclusive for the characterization of complex mixtures of lipid materials, thus the characterization of the triglyceride profiles was performed using an analytical procedure based on HPLC-ESI-Q-ToF. This paper describes the first application of HPLC-ESI-Q-ToF for the acquisition of the triglyceride profile in a modern paint sample, showing the potentialities of liquid chromatography in the field of lipid characterization in modern paint materials. Moreover, our results highlighted that the application of this approach can contribute to address dating, authenticity and conservation issues relative to modern and contemporary artworks. Copyright © 2015. Published by Elsevier B.V.
Nery, José Reinaldo Cardoso; Bonotto, Daniel Marcos
2011-04-01
Activity profiles of excess (210)Pb determined in three sediment cores from Amazon River mouth, Macapá city, Brazil, provided the evaluation of sedimentation rates, contributing to a better knowledge of the hydrological conditions in the site that is the capital of Amapá State and is drained by the waters of the huge Amazon River. Chemical data were also determined in the sediments, allowing identify signatures coupled to anthropogenic inputs held in the past in Amapá State. Significant direct relationships between LOI (loss on ignition) and organic matter were found for all sediments profiles. Silica was found to be inversely related to organic matter in the three profiles; its decrease accompanied an increase on the specific surface of the sediments. This relationship was confirmed by a great number of inverse significant correlations among silica and oxides Na(2)O, K(2)O, CaO, MgO, Al(2)O(3), P(2)O(5), Fe(2)O(3) and MnO. It was possible to identify the role of organic matter on adsorption of several oxides in the core sediments profiles. Apparent sediment mass accumulation rates corresponding to values between 450 and 2510 mg cm(-2)yr(-1) were obtained, and are compatible with the results of others studies. The (210)Pb activities in one sampling point suggested the occurrence of anthropogenic inputs related to the initial period of the mining activities conducted in Serra do Navio, Amapá State, for the commercialization of Mn ores. This was reinforced by the abrupt fluctuations in chemical data obtained for the sediments and composition of the interstitial waters occurring there. The Atlantic hurricane activity also appeared to affect the sedimentation rates in the area, as two different values were recorded in each profile. Copyright © 2011 Elsevier Ltd. All rights reserved.
Gouveia, Ana R; Freitas, Elisabete B; Galinha, Cláudia F; Carvalho, Gilda; Duque, Anouk F; Reis, Maria A M
2017-07-25
Polyhydroxyalkanoates (PHA) are a sustainable alternative to conventional plastics that can be obtained from industrial wastes/by-products using mixed microbial cultures (MMC). MMC PHA production is commonly carried out in a 3-stage process of acidogenesis, PHA culture selection and accumulation. This research focused on the possibility of tailoring PHA by controlling the acidogenic reactor operating conditions, namely pH, using cheese whey as model feedstock. The objective was to investigate the impact that dynamically varying the acidogenic pH, when targeting different PHA monomer profiles, had on the performance and microbial community profile of the anaerobic reactor. To accomplish this, an anaerobic reactor was continuously operated under dynamic pH changes, ranging from pH 4 to 7, turning to pH 6 after each change of pH. At pH 6, lactate and acetate were the dominant products (41-48% gCOD basis and 22-44% gCOD basis, respectively). At low pH, lactate production was higher while at high pH acetate production was favoured. Despite the dynamic change of pH, the fermentation product composition at pH 6 was always similar, showing the resilience of the process, i.e. when the same pH value was imposed, the culture produced the same metabolic products independently of the history of changes occurring in the system. The different fermentation product fractions led to PHAs of different compositions. The microbial community, analysed by high throughput sequencing of bacterial 16S rRNA gene fragments, was dominated by Lactobacillus, but varied markedly when subjected to the highest and lowest pH values of the tested range (4 and 7), with increase in the abundance of Lactococcus and a member of the Candidate Division TM7. Different bacterial profiles obtained at pH 6 during this dynamic operation were able to produce a consistent profile of fermentation products (and consequently a constant PHA composition), demonstrating the community's functional redundancy. Copyright © 2016 Elsevier B.V. All rights reserved.
Oliveira, Daniela A; Salvador, Ana Augusta; Smânia, Artur; Smânia, Elza F A; Maraschin, Marcelo; Ferreira, Sandra R S
2013-04-10
The possibility of increasing the aggregated value of the huge amount of residues generated by wineries around the world foment studies using the grape pomace - the residue from the wine production, composed by seed, skin and stems - to obtain functional ingredients. Nowadays, consumers in general prefer natural and safe products mainly for food and cosmetic fields, where the supercritical fluid extraction is of great importance due to the purity of the extracts provided. Therefore, the objective of this work is to evaluate the global extraction yield, the antimicrobial activity and the composition profile of Merlot and Syrah grape pomace extracts obtained by supercritical CO2 (SC-CO2) and CO2 added with co-solvent at pressures up to 300 bar and temperatures of 50 and 60 °C. The results were compared with the ones obtained by Soxhlet and by ultrasound-assisted leaching extraction methods. The main components from the extracts, identified by HPLC, were gallic acid, p-OH-benzoic acid, vanillic acid and epicatechin. The antibacterial and antifungal activities of the extracts were evaluated using four strains of bacteria (Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa) and three fungi strains (Candida albicans, Candida parapsilosis, Candida krusei). Despite lower extraction yield results, the supercritical fluid extracts presented the highest antimicrobial effectiveness compared to the other grape pomace extracts due to the presence of antimicrobial active compounds. Syrah extracts were less efficient against the microorganisms tested and Merlot extracts were more active against Gram-positive bacteria. Copyright © 2012 Elsevier B.V. All rights reserved.
Alfonse, Lauren E; Garrett, Amanda D; Lun, Desmond S; Duffy, Ken R; Grgicak, Catherine M
2018-01-01
DNA-based human identity testing is conducted by comparison of PCR-amplified polymorphic Short Tandem Repeat (STR) motifs from a known source with the STR profiles obtained from uncertain sources. Samples such as those found at crime scenes often result in signal that is a composite of incomplete STR profiles from an unknown number of unknown contributors, making interpretation an arduous task. To facilitate advancement in STR interpretation challenges we provide over 25,000 multiplex STR profiles produced from one to five known individuals at target levels ranging from one to 160 copies of DNA. The data, generated under 144 laboratory conditions, are classified by total copy number and contributor proportions. For the 70% of samples that were synthetically compromised, we report the level of DNA damage using quantitative and end-point PCR. In addition, we characterize the complexity of the signal by exploring the number of detected alleles in each profile. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
McElroy, Kenneth L., Jr.
1992-12-01
A method is presented for the determination of neutral gas densities in the ionosphere from rocket-borne measurements of UV atmospheric emissions. Computer models were used to calculate an initial guess for the neutral atmosphere. Using this neutral atmosphere, intensity profiles for the N2 (0,5) Vegard-Kaplan band, the N2 Lyman-Birge-Hopfield band system, and the OI2972 A line were calculated and compared with the March 1990 NPS MUSTANG data. The neutral atmospheric model was modified and the intensity profiles recalculated until a fit with the data was obtained. The neutral atmosphere corresponding to the intensity profile that fit the data was assumed to be the atmospheric composition prevailing at the time of the observation. The ion densities were then calculated from the neutral atmosphere using a photochemical model. The electron density profile calculated by this model was compared with the electron density profile measured by the U.S. Air Force Geophysics Laboratory at a nearby site.
Determination of fatty acid profile in ram spermatozoa and seminal plasma.
Díaz, R; Torres, M A; Bravo, S; Sanchez, R; Sepúlveda, N
2016-08-01
Fatty acids are important in male reproductive function because they are associated with membrane fluidity, acrosome reaction, sperm motility and viability, but limited information exists about the fatty acid profile of ram semen. Our aim was to determine the fatty acid composition in ram spermatozoa and seminal plasma. Sixty ejaculates were obtained from three ram (20 ejaculates/ram) using artificial vagina. Ram spermatozoa (RS) and seminal plasma (SP) were separated using centrifugation, and the fatty acids were analysed by gas chromatography. Total lipids obtained in ram spermatozoa were 1.8% and 1.6% in seminal plasma. Saturated fatty acid (SFA) was proportionally major in SP (66.6%) that RS (49.9%). The highest proportions of SFA corresponded to C4:0 (RS = 16.3% and SP = 28.8%) and C16:0 (RS = 16.3% and PS = 20%). The most important unsaturated fatty acid (UFA) was docosahexaenoic acid (DHA), 44.9% in RS and 31.5% in SP. The profile of fatty acid and their proportions showed differences between spermatozoa and seminal plasma. © 2015 Blackwell Verlag GmbH.
Bajoub, Aadil; Medina-Rodríguez, Santiago; Olmo-García, Lucía; Ajal, El Amine; Monasterio, Romina P; Hanine, Hafida; Fernández-Gutiérrez, Alberto; Carrasco-Pancorbo, Alegría
2016-12-28
Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars ("Picholine Marocaine", "Dahbia", "Haouzia" and "Menara"), and nine Mediterranean varieties recently introduced in Morocco ("Arbequina", "Arbosana", "Cornicabra", "Frantoio", "Hojiblanca", "Koroneiki", "Manzanilla", "Picholine de Languedoc" and "Picual"), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils.
Ebrahimi, Ali; Or, Dani
2016-09-01
Microbial communities inhabiting soil aggregates dynamically adjust their activity and composition in response to variations in hydration and other external conditions. These rapid dynamics shape signatures of biogeochemical activity and gas fluxes emitted from soil profiles. Recent mechanistic models of microbial processes in unsaturated aggregate-like pore networks revealed a highly dynamic interplay between oxic and anoxic microsites jointly shaped by hydration conditions and by aerobic and anaerobic microbial community abundance and self-organization. The spatial extent of anoxic niches (hotspots) flicker in time (hot moments) and support substantial anaerobic microbial activity even in aerated soil profiles. We employed an individual-based model for microbial community life in soil aggregate assemblies represented by 3D angular pore networks. Model aggregates of different sizes were subjected to variable water, carbon and oxygen contents that varied with soil depth as boundary conditions. The study integrates microbial activity within aggregates of different sizes and soil depth to obtain estimates of biogeochemical fluxes from the soil profile. The results quantify impacts of dynamic shifts in microbial community composition on CO2 and N2 O production rates in soil profiles in good agreement with experimental data. Aggregate size distribution and the shape of resource profiles in a soil determine how hydration dynamics shape denitrification and carbon utilization rates. Results from the mechanistic model for microbial activity in aggregates of different sizes were used to derive parameters for analytical representation of soil biogeochemical processes across large scales of practical interest for hydrological and climate models. © 2016 John Wiley & Sons Ltd.
Chemical characteristics and volatile profile of genetically modified peanut cultivars.
Ng, Ee Chin; Dunford, Nurhan T; Chenault, Kelly
2008-10-01
Genetic engineering has been used to modify peanut cultivars for improving agronomic performance and pest resistance. Food products developed through genetic engineering have to be assessed for their safety before approval for human consumption. Preservation of desirable chemical, flavor and aroma attributes of the peanut cultivars during the genetic modifications is critical for acceptance of genetically modified peanuts (GMP) by the food industry. Hence, the main objective of this study is to examine chemical characteristics and volatile profile of GMP. The genetically modified peanut cultivars, 188, 540 and 654 were obtained from the USDA-ARS in Stillwater, Oklahoma. The peanut variety Okrun was examined as a control. The volatile analysis was performed using a gas chromatograph/mass spectrometer (GC/MS) equipped with an olfactory detector. The peanut samples were also analyzed for their moisture, ash, protein, sugar and oil compositions. Experimental results showed that the variations in nutritional composition of peanut lines examined in this study were within the values reported for existing cultivars. There were minor differences in volatile profile among the samples. The implication of this study is significant, since it shows that peanut cultivars with greater pest and fungal resistance were successfully developed without major changes in their chemical characteristics.
Determination and discrimination of biodiesel fuels by gas chromatographic and chemometric methods
NASA Astrophysics Data System (ADS)
Milina, R.; Mustafa, Z.; Bojilov, D.; Dagnon, S.; Moskovkina, M.
2016-03-01
Pattern recognition method (PRM) was applied to gas chromatographic (GC) data for a fatty acid methyl esters (FAME) composition of commercial and laboratory synthesized biodiesel fuels from vegetable oils including sunflower, rapeseed, corn and palm oils. Two GC quantitative methods to calculate individual fames were compared: Area % and internal standard. The both methods were applied for analysis of two certified reference materials. The statistical processing of the obtained results demonstrates the accuracy and precision of the two methods and allows them to be compared. For further chemometric investigations of biodiesel fuels by their FAME-profiles any of those methods can be used. PRM results of FAME profiles of samples from different vegetable oils show a successful recognition of biodiesels according to the feedstock. The information obtained can be used for selection of feedstock to produce biodiesels with certain properties, for assessing their interchangeability, for fuel spillage and remedial actions in the environment.
Design and Test of Low-Profile Composite Aerospace Tank Dome
NASA Technical Reports Server (NTRS)
Ahmed, R.
1999-01-01
This report summarizes the design, analysis, manufacture, and test of a subscale, low-profile composite aerospace dome under internal pressure. A low-profile dome has a radius-to-height ratio greater than the square root of two. This effort demonstrated that a low-profile composite dome with a radius-to-height ratio of three was a feasible design and could adequately withstand the varying stress states resulting from internal pressurization. Test data for strain and displacement versus pressure are provided to validate the design.
Development and evaluation of new multiple-unit levodopa sustained-release floating dosage forms.
Goole, J; Vanderbist, F; Amighi, K
2007-04-04
This work relates to the development and the in vitro evaluation of sustained-release minitablets (MT), prepared by melt granulation and subsequent compression, which are designed to float over an extended period of time. Levodopa was used as a model drug. The importance of the composition and manufacturing parameters of the MT on their floating and dissolution properties was then examined. The investigation showed that MT composition and MT diameter had the greatest influence on drug release, which was sustained for more than 8h. By using the same formulation, the best floating properties were obtained with 3mm MT prepared at low compression forces ranging between 50 and 100N. Their resultant-weight (RW) values were always higher than those obtained with a marketed HBS dosage form within 13h. When they were filled into gelatin capsules, no sticking was observed. By evaluating the dissolution profiles of levodopa at different pH values, it was found that dissolution profiles depend more on the prolonged-release ability of Methocel K15M than on the pH-dependent solubility of levodopa. Finally, the robustness of the floating MT was assessed by testing the drug release variability in function of the stirring conditions during dissolution tests.
NASA Astrophysics Data System (ADS)
Kar, Siddhartha; Chakraborty, Sujoy; Dey, Vidyut; Ghosh, Subrata Kumar
2017-10-01
This paper investigates the application of Taguchi method with fuzzy logic for multi objective optimization of roughness parameters in electro discharge coating process of Al-6351 alloy with powder metallurgical compacted SiC/Cu tool. A Taguchi L16 orthogonal array was employed to investigate the roughness parameters by varying tool parameters like composition and compaction load and electro discharge machining parameters like pulse-on time and peak current. Crucial roughness parameters like Centre line average roughness, Average maximum height of the profile and Mean spacing of local peaks of the profile were measured on the coated specimen. The signal to noise ratios were fuzzified to optimize the roughness parameters through a single comprehensive output measure (COM). Best COM obtained with lower values of compaction load, pulse-on time and current and 30:70 (SiC:Cu) composition of tool. Analysis of variance is carried out and a significant COM model is observed with peak current yielding highest contribution followed by pulse-on time, compaction load and composition. The deposited layer is characterised by X-Ray Diffraction analysis which confirmed the presence of tool materials on the work piece surface.
Numerical Analysis of Prefabricated Steel-Concrete Composite Floor in Typical Lipsk Building
NASA Astrophysics Data System (ADS)
Lacki, Piotr; Kasza, Przemysław; Derlatka, Anna
2017-12-01
The aim of the work was to perform numerical analysis of a steel-concrete composite floor located in a LIPSK type building. A numerical model of the analytically designed floor was performed. The floor was in a six-storey, retail and service building. The thickness of a prefabricated slab was 100 mm. The two-row, crisscrossed reinforcement of the slab was made from φ16 mm rods with a spacing of 150 x 200 mm. The span of the beams made of steel IPE 160 profiles was 6.00 m and they were spaced every 1.20 m. The steelconcrete composite was obtained using 80×16 Nelson fasteners. The numerical analysis was carried out using the ADINA System based on the Finite Element Method. The stresses and strains in the steel and concrete elements, the distribution of the forces in the reinforcement bars and cracking in concrete were evaluated. The FEM model was made from 3D-solid finite elements (IPE profile and concrete slab) and truss elements (reinforcement bars). The adopted steel material model takes into consideration the plastic state, while the adopted concrete material model takes into account material cracks.
Relationship between the sensory-determined astringency and the flavanolic composition of red wines.
Quijada-Morín, Natalia; Regueiro, Jorge; Simal-Gándara, Jesús; Tomás, Esperanza; Rivas-Gonzalo, Julián C; Escribano-Bailón, M Teresa
2012-12-19
The relationship between the proanthocyanidin profile and the perceived astringency was assessed in 13 commercial Tempranillo red wines. The concentration and compositional information were obtained by liquid chromatography with diode array detection coupled to electrospray ionization mass spectrometry after acid-catalyzed depolymerization of wine proanthocyanidins in the presence of excess phloroglucinol. Statistical analysis of the results showed significant correlations between sensory and chemical determinations. Astringency was more affected by the subunit composition than by the total concentration or the average degree of polymerization of wine proanthocyanidins. Higher proportions of epicatechin (EC) subunits in extension positions and gallocatechin (GC) subunits in terminal positions were shown to increase astringency. On the contrary, the amount of epigallocatechin (EGC) in both extension and terminal positions was negatively correlated with the perceived astringency.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Soh, R; Lee, J; Harianto, F
Purpose: To determine and compare the correction factors obtained for TLDs in 2 × 2cm{sup 2} small field in lung heterogenous phantom using Acuros XB (AXB) and EGSnrc. Methods: This study will simulate the correction factors due to the perturbation of TLD-100 chips (Harshaw/Thermoscientific, 3 × 3 × 0.9mm{sup 3}, 2.64g/cm{sup 3}) in small field lung medium for Stereotactic Body Radiation Therapy (SBRT). A physical lung phantom was simulated by a 14cm thick composite cork phantom (0.27g/cm{sup 3}, HU:-743 ± 11) sandwiched between 4cm thick Plastic Water (CIRS,Norfolk). Composite cork has been shown to be a good lung substitute materialmore » for dosimetric studies. 6MV photon beam from Varian Clinac iX (Varian Medical Systems, Palo Alto, CA) with field size 2 × 2cm{sup 2} was simulated. Depth dose profiles were obtained from the Eclipse treatment planning system Acuros XB (AXB) and independently from DOSxyznrc, EGSnrc. Correction factors was calculated by the ratio of unperturbed to perturbed dose. Since AXB has limitations in simulating actual material compositions, EGSnrc will also simulate the AXB-based material composition for comparison to the actual lung phantom. Results: TLD-100, with its finite size and relatively high density, causes significant perturbation in 2 × 2cm{sup 2} small field in a low lung density phantom. Correction factors calculated by both EGSnrc and AXB was found to be as low as 0.9. It is expected that the correction factor obtained by EGSnrc wlll be more accurate as it is able to simulate the actual phantom material compositions. AXB have a limited material library, therefore it only approximates the composition of TLD, Composite cork and Plastic water, contributing to uncertainties in TLD correction factors. Conclusion: It is expected that the correction factors obtained by EGSnrc will be more accurate. Studies will be done to investigate the correction factors for higher energies where perturbation may be more pronounced.« less
Strong-field Photoionization of Sputtered Neutral Molecules for Molecular Depth Profiling
Willingham, D; Brenes, D. A.; Wucher, A
2009-01-01
Molecular depth profiles of an organic thin film of guanine vapor deposited onto a Ag substrate are obtained using a 40 keV C60 cluster ion beam in conjunction with time-of-flight secondary ion mass spectrometric (ToF-SIMS) detection. Strong-field, femtosecond photoionization of intact guanine molecules is used to probe the neutral component of the profile for direct comparison with the secondary ion component. The ability to simultaneously acquire secondary ions and photoionized neutral molecules reveals new fundamental information about the factors that influence the properties of the depth profile. Results show that there is an increased ionization probability for protonated molecular ions within the first 10 nm due to the generation of free protons within the sample. Moreover, there is a 50% increase in fragment ion signal relative to steady state values 25 nm before reaching the guanine/Ag interface as a result of interfacial chemical damage accumulation. An altered layer thickness of 20 nm is observed as a consequence of ion beam induced chemical mixing. In general, we show that the neutral component of a molecular depth profile using the strong-field photoionization technique can be used to elucidate the effects of variations in ionization probability on the yield of molecular ions as well as to aid in obtaining accurate information about depth dependent chemical composition that cannot be extracted from TOF-SIMS data alone. PMID:20495665
Padró, Juan M; Osorio-Grisales, Jaiver; Arancibia, Juan A; Olivieri, Alejandro C; Castells, Cecilia B
2015-07-01
Valuable quantitative information could be obtained from strongly overlapped chromatographic profiles of two enantiomers by using proper chemometric methods. Complete separation profiles where the peaks are fully resolved are difficult to achieve in chiral separation methods, and this becomes a particularly severe problem in case that the analyst needs to measure the chiral purity, i.e., when one of the enantiomers is present in the sample in very low concentrations. In this report, we explore the scope of a multivariate chemometric technique based on unfolded partial least-squares regression, as a mathematical tool to solve this quite frequent difficulty. This technique was applied to obtain quantitative results from partially overlapped chromatographic profiles of R- and S-ketoprofen, with different values of enantioresolution factors (from 0.81 down to less than 0.2 resolution units), and also at several different S:R enantiomeric ratios. Enantiomeric purity below 1% was determined with excellent precision even from almost completely overlapped signals. All these assays were tested on the most demanding condition, i.e., when the minor peak elutes immediately after the main peak. The results were validated using univariate calibration of completely resolved profiles and the method applied to the determination of enantiomeric purity of commercial pharmaceuticals. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ríos-Reina, Rocío; Morales, M Lourdes; García-González, Diego L; Amigo, José M; Callejón, Raquel M
2018-03-01
High-quality wine vinegars have been registered in Spain under protected designation of origin (PDO): "Vinagre de Jerez", "Vinagre de Condado de Huelva" and "Vinagre de Montilla-Moriles". The raw material, production and aging processes determine their quality and their aromatic composition. Vinegar volatile profile is usually analyzed by gas chromatography-mass spectrometry (GC-MS), being necessary a previous extraction step. Thus, three different sampling methods (Headspace solid phase microextraction "HS-SPME", Headspace stir bar sorptive extraction "HSSE" and Dynamic headspace extraction "DHS") were studied for the analysis of the volatile composition of Spanish PDO wine vinegars. Multivariate curve resolution (MCR) was used to solve chromatographic problems, improving the results obtained. Principal component analysis (PCA) showed that not all the sampling methods were equally suitable for the characterization and differentiation between PDOs and categories, being HSSE the technique that made able the best vinegar characterization. Copyright © 2017 Elsevier Ltd. All rights reserved.
González-Sáiz, J M; Esteban-Díez, I; Rodríguez-Tecedor, S; Pérez-Del-Notario, N; Arenzana-Rámila, I; Pizarro, C
2014-12-15
The aim of the present work was to evaluate the effect of the main factors conditioning accelerated ageing processes (oxygen dose, chip dose, wood origin, toasting degree and maceration time) on the phenolic and chromatic profiles of red wines by using a multivariate strategy based on experimental design methodology. The results obtained revealed that the concentrations of monomeric anthocyanins and flavan-3-ols could be modified through the application of particular experimental conditions. This fact was particularly remarkable since changes in phenolic profile were closely linked to changes observed in chromatic parameters. The main strength of this study lies in the possibility of using its conclusions as a basis to make wines with specific colour properties based on quality criteria. To our knowledge, the influence of such a large number of alternative ageing parameters on wine phenolic composition and chromatic attributes has not been studied previously using a comprehensive experimental design methodology. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Carlson, Barbara E.; Prather, Michael J.; Rossow, William B.
1987-01-01
Chemical equilibrium models used currently to interpret observations of Jupiter are reexamined using new data defining thermal profiles, which are substantially different from those used in the previous models. A model is developed for the chemical reactions controlling the composition of the upper troposphere on Jupiter, specifically the cloud-forming region from 10 bar to 0.1 bar, which includes, for the first time, the effects of aqueous chemistry on the composition and the vertical distribution of many measurable species in the atmosphere, identifying the factors influencing their abundances above the H2O cloud. The thermodynamic data for potential condensates on Jupiter, i.e., NH3(s), NH4SH(s), (NH4)2S(s), and H2S(s), are reexamined, recognizing the lack of data on sulfides for the temperature range of interest on Jupiter. Vertical profiles of mixing ratios for CO2, H2S, NH3, and H2, obtained for several assumed bulk abundances with respect to solar, are presented.
Cerrillo, I; Fernández-Pachón, M S; Collado-González, J; Escudero-López, B; Berná, G; Herrero-Martín, G; Martín, F; Ferreres, F; Gil-Izquierdo, A
2015-06-01
The fermentation of fruit produces significant changes in their nutritional composition. An orange beverage has been obtained from the controlled alcoholic fermentation and thermal pasteurization of orange juice. A study was performed to determine the influence of both processes on its amino acid profile. UHPLC-QqQ-MS/MS was used for the first time for analysis of orange juice samples. Out of 29 amino acids and derivatives identified, eight (ethanolamine, ornithine, phosphoethanolamine, α-amino-n-butyric acid, hydroxyproline, methylhistidine, citrulline, and cystathionine) have not previously been detected in orange juice. The amino acid profile of the orange juice was not modified by its processing, but total amino acid content of the juice (8194 mg/L) was significantly increased at 9 days of fermentation (13,324 mg/L). Although the pasteurization process produced partial amino acid degradation, the total amino acid content was higher in the final product (9265 mg/L) than in the original juice, enhancing its nutritional value.
Farabegoli, Federica; Pirini, Maurizio; Rotolo, Magda; Silvi, Marina; Testi, Silvia; Ghidini, Sergio; Zanardi, Emanuela; Remondini, Daniel; Bonaldo, Alessio; Parma, Luca; Badiani, Anna
2018-06-08
The authenticity of fish products has become an imperative issue for authorities involved in the protection of consumers against fraudulent practices and in the market stabilization. The present study aimed to provide a method for authentication of European sea bass (Dicentrarchus labrax) according to the requirements for seafood labels (Regulation 1379/2013/EU). Data on biometric traits, fatty acid profile, elemental composition, and isotopic abundance of wild and reared (intensively, semi-intensively and extensively) specimens from 18 Southern European sources (n = 160) were collected and clustered in 6 sets of parameters, then subjected to multivariate analysis. Correct allocations of subjects according to their production method, origin and stocking density were demonstrated with good approximation rates (94%, 92% and 92%, respectively) using fatty acid profiles. Less satisfying results were obtained using isotopic abundance, biometric traits, and elemental composition. The multivariate analysis also revealed that extensively reared subjects cannot be analytically discriminated from wild ones.
Lv, Y; Cui, J; Jiang, Z M; Yang, X J
2013-02-15
Atomic force microscopy imaging combined with selective chemical etching is employed to quantitatively investigate three-dimensional (3D) composition distributions of single GeSi quantum rings (QRs). In addition, the 3D quantitative composition distributions and the corresponding conductance distributions are simultaneously obtained on the same single GeSi QRs by conductive atomic force microscopy combined with selective chemical etching, allowing us to investigate the correlations between the conductance and composition distributions of single QRs. The results show that the QRs' central holes have higher Ge content, but exhibit lower conductance, indicating that the QRs' conductance distribution is not consistent with their composition distribution. By comparing the topography, composition and conductance profiles of the same single QRs before and after different etching processes, it is found that the conductance distributions of GeSi QRs do not vary with the change of composition distribution. Instead, the QRs' conductance distributions are found to be consistent with their topographic shapes, which can be supposed to be due to the shape determined electronic structures.
Gao, Wen; Yang, Hua; Qi, Lian-Wen; Liu, E-Hu; Ren, Mei-Ting; Yan, Yu-Ting; Chen, Jun; Li, Ping
2012-07-06
Plant-based medicines become increasingly popular over the world. Authentication of herbal raw materials is important to ensure their safety and efficacy. Some herbs belonging to closely related species but differing in medicinal properties are difficult to be identified because of similar morphological and microscopic characteristics. Chromatographic fingerprinting is an alternative method to distinguish them. Existing approaches do not allow a comprehensive analysis for herbal authentication. We have now developed a strategy consisting of (1) full metabolic profiling of herbal medicines by rapid resolution liquid chromatography (RRLC) combined with quadrupole time-of-flight mass spectrometry (QTOF MS), (2) global analysis of non-targeted compounds by molecular feature extraction algorithm, (3) multivariate statistical analysis for classification and prediction, and (4) marker compounds characterization. This approach has provided a fast and unbiased comparative multivariate analysis of the metabolite composition of 33-batch samples covering seven Lonicera species. Individual metabolic profiles are performed at the level of molecular fragments without prior structural assignment. In the entire set, the obtained classifier for seven Lonicera species flower buds showed good prediction performance and a total of 82 statistically different components were rapidly obtained by the strategy. The elemental compositions of discriminative metabolites were characterized by the accurate mass measurement of the pseudomolecular ions and their chemical types were assigned by the MS/MS spectra. The high-resolution, comprehensive and unbiased strategy for metabolite data analysis presented here is powerful and opens the new direction of authentication in herbal analysis. Copyright © 2012 Elsevier B.V. All rights reserved.
Techniques for carrying out radiative transfer calculations for the Martian atmospheric dust
NASA Technical Reports Server (NTRS)
Aronson, J. R.; Emslie, A. G.; Strong, P. F.
1974-01-01
A description is given of the modification of a theory on the reflectance of particulate media so as to apply it to analysis of the infrared spectra obtained by the IRIS instrument on Mariner 9. With the aid of this theory and the optical constants of muscovite mica, quartz, andesite, anorthosite, diopside pyroxenite, and dunite, modeling calculations were made to refine previous estimates of the mineralogical composition of the Martian dust particles. These calculations suggest that a feldspar rich mixture is a very likely composition for the dust particles. The optical constants used for anorthosite and diopside pyroxenite were derived during this program from reflectance measurements. Those for the mica were derived from literature reflectance data. Finally, a computer program was written to invert the measured radiance data so as to obtain the absorption coefficient spectrum which should then be independent of the temperature profile and gaseous component effects.
Alonso-Miravalles, Loreto; O'Mahony, James A
2018-05-07
The objectives of this study were to investigate the nutrient composition, protein profile, morphology, and pasting properties of protein-rich pseudocereal ingredients (quinoa, amaranth, and buckwheat) and compare them to the more common rice and maize flours. Literature concerning protein-rich pseudocereal ingredients is very limited, mainly to protein profiling. The concentrations of macronutrients (i.e., ash, fat, and protein, as well as soluble, insoluble and total dietary fibre) were significantly higher for the protein-rich variants of pseudocereal-based flours than their regular protein content variants and the rice and maize flours. On profiling the protein component using sodium dodecyl sulfate⁻polyacrylamide gel electrophoresis (SDS-PAGE), all samples showed common bands at ~50 kDa and low molecular weight bands corresponding to the globulin fraction (~50 kDa) and albumin fraction (~10 kDa), respectively; except rice, in which the main protein was glutelin. The morphology of the starch granules was studied using scanning electron microscopy with quinoa and amaranth showing the smallest sized granules, while buckwheat, rice, and maize had the largest starch granules. The pasting properties of the ingredients were generally similar, except for buckwheat and amaranth, which showed the highest and lowest final viscosity, respectively. The results obtained in this study can be used to better understand the functionality and food applications of protein-rich pseudocereal ingredients.
Reinartz, Roman; Wang, Shanshan; Kebir, Sied; Silver, Daniel J.; Wieland, Anja; Zheng, Tong; Küpper, Marius; Rauschenbach, Laurèl; Fimmers, Rolf; Shepherd, Timothy M.; Trageser, Daniel; Till, Andreas; Schäfer, Niklas; Glas, Martin; Hillmer, Axel M.; Cichon, Sven; Smith, Amy A.; Pietsch, Torsten; Liu, Ying; Reynolds, Brent A.; Yachnis, Anthony; Pincus, David W.; Simon, Matthias; Brüstle, Oliver; Steindler, Dennis A.; Scheffler, Björn
2016-01-01
Purpose Investigation of clonal heterogeneity may be key to understanding mechanisms of therapeutic failure in human cancer. However, little is known on the consequences of therapeutic intervention on the clonal composition of solid tumors. Experimental Design Here, we used 33 single cell-derived subclones generated from five clinical glioblastoma specimens for exploring intra- and inter-individual spectra of drug resistance profiles in vitro. In a personalized setting, we explored whether differences in pharmacological sensitivity among subclones could be employed to predict drug-dependent changes to the clonal composition of tumors. Results Subclones from individual tumors exhibited a remarkable heterogeneity of drug resistance to a library of potential anti-glioblastoma compounds. A more comprehensive intra-tumoral analysis revealed that stable genetic and phenotypic characteristics of co-existing subclones could be correlated with distinct drug sensitivity profiles. The data obtained from differential drug response analysis could be employed to predict clonal population shifts within the naïve parental tumor in vitro and in orthotopic xenografts. Furthermore, the value of pharmacological profiles could be shown for establishing rational strategies for individualized secondary lines of treatment. Conclusions Our data provide a previously unrecognized strategy for revealing functional consequences of intra-tumor heterogeneity by enabling predictive modeling of treatment-related subclone dynamics in human glioblastoma. PMID:27521447
NASA Astrophysics Data System (ADS)
Llorens-Chiralt, R.; Weiss, P.; Mikonsaari, I.
2014-05-01
Material characterization is one of the key steps when conductive polymers are developed. The dispersion of carbon nanotubes (CNTs) in a polymeric matrix using melt mixing influence final composite properties. The compounding becomes trial and error using a huge amount of materials, spending time and money to obtain competitive composites. Traditional methods to carry out electrical conductivity characterization include compression and injection molding. Both methods need extra equipments and moulds to obtain standard bars. This study aims to investigate the accuracy of the data obtained from absolute resistance recorded during the melt compounding, using an on-line setup developed by our group, and to correlate these values with off-line characterization and processing parameters (screw/barrel configuration, throughput, screw speed, temperature profile and CNTs percentage). Compounds developed with different percentages of multi walled carbon nanotubes (MWCNTs) and polycarbonate has been characterized during and after extrusion. Measurements, on-line resistance and off-line resistivity, showed parallel response and reproducibility, confirming method validity. The significance of the results obtained stems from the fact that we are able to measure on-line resistance and to change compounding parameters during production to achieve reference values reducing production/testing cost and ensuring material quality. Also, this method removes errors which can be found in test bars development, showing better correlation with compounding parameters.
Rinchard, Jacques; Kimmel, David G.
2017-01-01
The variability in zooplankton fatty acid composition may be an indicator of larval fish habitat quality as fatty acids are linked to fish larval growth and survival. We sampled an anadromous fish nursery, the Chowan River, during spring of 2013 in order to determine how the seston fatty acid composition varied in comparison with the zooplankton community composition and fatty acid composition during the period of anadromous larval fish residency. The seston fatty acid profiles showed no distinct pattern in relation to sampling time or location. The mesozooplankton community composition varied spatially and the fatty acid profiles were typical of freshwater species in April. The Chowan River experienced a saltwater intrusion event during May, which resulted in brackish water species dominating the zooplankton community and the fatty acid profile showed an increase in polyunsaturated fatty acids (PUFA), in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The saltwater intrusion event was followed by an influx of freshwater due to high precipitation levels in June. The zooplankton community composition once again became dominated by freshwater species and the fatty acid profiles shifted to reflect this change; however, EPA levels remained high, particularly in the lower river. We found correlations between the seston, microzooplankton and mesozooplankton fatty acid compositions. Salinity was the main factor correlated to the observed pattern in species composition, and fatty acid changes in the mesozooplankton. These data suggest that anadromous fish nursery habitat likely experiences considerable spatial variability in fatty acid profiles of zooplankton prey and that are correlated to seston community composition and hydrodynamic changes. Our results also suggest that sufficient prey density as well as a diverse fatty acid composition is present in the Chowan River to support larval fish production. PMID:28828262
NASA Astrophysics Data System (ADS)
Sinha, Mangalika; Modi, Mohammed H.
2017-10-01
In-depth compositional analysis of 240 Å thick aluminium oxide thin film has been carried out using soft x-ray reflectivity (SXR) and x-ray photoelectron spectroscopy technique (XPS). The compositional details of the film is estimated by modelling the optical index profile obtained from the SXR measurements over 60-200 Å wavelength region. The SXR measurements are carried out at Indus-1 reflectivity beamline. The method suggests that the principal film region is comprised of Al2O3 and AlOx (x = 1.6) phases whereas the interface region comprised of SiO2 and AlOx (x = 1.6) mixture. The soft x-ray reflectivity technique combined with XPS measurements explains the compositional details of principal layer. Since the interface region cannot be analyzed with the XPS technique in a non-destructive manner in such a case the SXR technique is a powerful tool for nondestructive compositional analysis of interface region.
Aerobic power and anthropometric characteristics of elite basketball referees.
Leicht, A S
2007-03-01
The current study aimed to document the aerobic power and body composition of elite basketball referees. Prior to the 2000/2001 Men's National Basketball League season, 25 male elite referees completed the Multistage Shuttle run test followed by body composition (body fat%) determination via bioelectrical impedance (BI) (Adult and Athlete modes) and a restricted anthropometric profile. Significant correlations between BI and anthropometric measures were examined via Pearson product correlation coefficients. Referees demonstrated a mean (SD) aerobic power of 50.8 (3.2) mL . kg-1 . min(-1) and body fat% of 23.8% (8.4%). Body fat% was similar for BI (Adult) and several anthropometric equations. Significant correlations were obtained between BI (Adult) and body fat%, and BI (Adult) and sum of skinfolds. Similar correlations were obtained for BI (Athlete) mode despite a significantly lower body fat%. Regression equations for the prediction of body fat% and sum of skinfolds from BI (Adult) were determined. Elite basketball referees demonstrated significantly greater aerobic power and similar body composition to the general community. In the euhydrated state, BI (Adult) provided a valid measurement of body fat% in elite basketball referees.
Experimental and Numerical Analysis of Notched Composites Under Tension Loading
NASA Astrophysics Data System (ADS)
Aidi, Bilel; Case, Scott W.
2015-12-01
Experimental quasi-static tests were performed on center notched carbon fiber reinforced polymer (CFRP) composites having different stacking sequences made of G40-600/5245C prepreg. The three-dimensional Digital Image Correlation (DIC) technique was used during quasi-static tests conducted on quasi-isotropic notched samples to obtain the distribution of strains as a function of applied stress. A finite element model was built within Abaqus to predict the notched strength and the strain profiles for comparison with measured results. A user-material subroutine using the multi-continuum theory (MCT) as a failure initiation criterion and an energy-based damage evolution law as implemented by Autodesk Simulation Composite Analysis (ASCA) was used to conduct a quantitative comparison of strain components predicted by the analysis and obtained in the experiments. Good agreement between experimental data and numerical analyses results are observed. Modal analysis was carried out to investigate the effect of static damage on the dominant frequencies of the notched structure using the resulted degraded material elements. The first in-plane mode was found to be a good candidate for tracking the level of damage.
Stiffness distribution in insect cuticle: a continuous or a discontinuous profile?
Rajabi, H; Jafarpour, M; Darvizeh, A; Dirks, J-H; Gorb, S N
2017-07-01
Insect cuticle is a biological composite with a high degree of complexity in terms of both architecture and material composition. Given the complex morphology of many insect body parts, finite-element (FE) models play an important role in the analysis and interpretation of biomechanical measurements, taken by either macroscopic or nanoscopic techniques. Many previous studies show that the interpretation of nanoindentation measurements of this layered composite material is very challenging. To develop accurate FE models, it is of particular interest to understand more about the variations in the stiffness through the thickness of the cuticle. Considering the difficulties of making direct measurements, in this study, we use the FE method to analyse previously published data and address this issue numerically. For this purpose, sets of continuous or discontinuous stiffness profiles through the thickness of the cuticle were mathematically described. The obtained profiles were assigned to models developed based on the cuticle of three insect species with different geometries and layer configurations. The models were then used to simulate the mechanical behaviour of insect cuticles subjected to nanoindentation experiments. Our results show that FE models with discontinuous exponential stiffness gradients along their thickness were able to predict the stress and deformation states in insect cuticle very well. Our results further suggest that, for more accurate measurements and interpretation of nanoindentation test data, the ratio of the indentation depth to cuticle thickness should be limited to 7% rather than the traditional '10% rule'. The results of this study thus might be useful to provide a deeper insight into the biomechanical consequences of the distinct material distribution in insect cuticle and also to form a basis for more realistic modelling of this complex natural composite. © 2017 The Author(s).
Measuring Compositions in Organic Depth Profiling: Results from a VAMAS Interlaboratory Study.
Shard, Alexander G; Havelund, Rasmus; Spencer, Steve J; Gilmore, Ian S; Alexander, Morgan R; Angerer, Tina B; Aoyagi, Satoka; Barnes, Jean-Paul; Benayad, Anass; Bernasik, Andrzej; Ceccone, Giacomo; Counsell, Jonathan D P; Deeks, Christopher; Fletcher, John S; Graham, Daniel J; Heuser, Christian; Lee, Tae Geol; Marie, Camille; Marzec, Mateusz M; Mishra, Gautam; Rading, Derk; Renault, Olivier; Scurr, David J; Shon, Hyun Kyong; Spampinato, Valentina; Tian, Hua; Wang, Fuyi; Winograd, Nicholas; Wu, Kui; Wucher, Andreas; Zhou, Yufan; Zhu, Zihua; Cristaudo, Vanina; Poleunis, Claude
2015-08-20
We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) interlaboratory study on the measurement of composition in organic depth profiling. Layered samples with known binary compositions of Irganox 1010 and either Irganox 1098 or Fmoc-pentafluoro-l-phenylalanine in each layer were manufactured in a single batch and distributed to more than 20 participating laboratories. The samples were analyzed using argon cluster ion sputtering and either X-ray photoelectron spectroscopy (XPS) or time-of-flight secondary ion mass spectrometry (ToF-SIMS) to generate depth profiles. Participants were asked to estimate the volume fractions in two of the layers and were provided with the compositions of all other layers. Participants using XPS provided volume fractions within 0.03 of the nominal values. Participants using ToF-SIMS either made no attempt, or used various methods that gave results ranging in error from 0.02 to over 0.10 in volume fraction, the latter representing a 50% relative error for a nominal volume fraction of 0.2. Error was predominantly caused by inadequacy in the ability to compensate for primary ion intensity variations and the matrix effect in SIMS. Matrix effects in these materials appear to be more pronounced as the number of atoms in both the primary analytical ion and the secondary ion increase. Using the participants' data we show that organic SIMS matrix effects can be measured and are remarkably consistent between instruments. We provide recommendations for identifying and compensating for matrix effects. Finally, we demonstrate, using a simple normalization method, that virtually all ToF-SIMS participants could have obtained estimates of volume fraction that were at least as accurate and consistent as XPS.
Measuring Compositions in Organic Depth Profiling: Results from a VAMAS Interlaboratory Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shard, A. G.; Havelund, Rasmus; Spencer, Steve J.
We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) interlaboratory study on the measurement of composition in organic depth profiling. Layered samples with known binary compositions of Irganox 1010 and either Irganox 1098 or Fmoc-pentafluoro-L-phenylalanine in each layer were manufactured in a single batch and distributed to more than 20 participating laboratories. The samples were analyzed using argon cluster ion sputtering and either X-ray Photoelectron Spectroscopy (XPS) or Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) to generate depth profiles. Participants were asked to estimate the volume fractions in two of the layers and were provided withmore » the compositions of all other layers. Participants using XPS provided volume fractions within 0.03 of the nominal values. Participants using ToF-SIMS either made no attempt, or used various methods that gave results ranging in error from 0.02 to over 0.10 in volume fraction, the latter representing a 50% relative error for a nominal volume fraction of 0.2. Error was predominantly caused by inadequacy in the ability to compensate for primary ion intensity variations and the matrix effect in SIMS. Matrix effects in these materials appear to be more pronounced as the number of atoms in both the primary analytical ion and the secondary ion increase. Using the participants’ data we show that organic SIMS matrix effects can be measured and are remarkably consistent between instruments. We provide recommendations for identifying and compensating for matrix effects. Finally we demonstrate, using a simple normalization method, that virtually all ToF-SIMS participants could have obtained estimates of volume fraction that were at least as accurate and consistent as XPS.« less
The lateritic profile of Balkouin, Burkina Faso: Geochemistry, mineralogy and genesis
NASA Astrophysics Data System (ADS)
Giorgis, Ilaria; Bonetto, Sabrina; Giustetto, Roberto; Lawane, Abdou; Pantet, Anne; Rossetti, Piergiorgio; Thomassin, Jean-Hugues; Vinai, Raffaele
2014-02-01
This study reports on the geochemical and mineralogical characterization of a lateritic profile cropping out in the Balkouin area, Central Burkina Faso, aimed at obtaining a better understanding of the processes responsible for the formation of the laterite itself and the constraints to its development. The lateritic profile rests on a Paleoproterozoic basement mostly composed of granodioritic rocks related to the Eburnean magmatic cycle passing upwards to saprolite and consists of four main composite horizons (bottom to top): kaolinite and clay-rich horizons, mottled laterite and iron-rich duricrust. In order to achieve such a goal, a multi-disciplinary analytical approach was adopted, which includes inductively coupled plasma (ICP) atomic emission and mass spectrometries (ICP-AES and ICP-MS respectively), X-ray powder diffraction (XRPD), scanning electron microscopy with energy dispersive spectrometry (SEM-EDS) and micro-Raman spectroscopy.
Oxidation and textural characteristics of butter and ice cream with modified fatty acid profiles.
Gonzalez, S; Duncan, S E; O'Keefe, S F; Sumner, S S; Herbein, J H
2003-01-01
The primary objective of this study was to evaluate oxidation and firmness of butter and ice cream made with modified milkfat containing enhanced amounts of linoleic acid or oleic acid. The influence of the fatty acid profile of the HO milkfat relating to product properties as compared with the influence the fatty acid profile of the HL milkfat was the main focus of the research. Altering the degree of unsaturation in milkfat may affect melting characteristics and oxidation rates, leading to quality issues in dairy products. Three milkfat compositions (high-oleic, high-linoleic, and control) were obtained by modifying the diets of Holstein cows. Ice cream and butter were processed from milkfat obtained from cows in each dietary group. Butter and ice cream samples were analyzed to determine fatty acid profile and firmness. High-oleic milkfat resulted in a softer butter. Solid fat index of high-oleic and high-linoleic milkfat was lower than the control. Control ice cream mix had higher viscosity compared with high-oleic and high-linoleic, but firmness of all ice creams was similar when measured between -17 and -13 degrees C. Nutritional and textural properties of butter and ice cream can be improved by modifying the diets of cows.
Wang, Benlian; Sun, Gang; Anderson, David R.; Jia, Minghong; Previs, Stephen; Anderson, Vernon E.
2007-01-01
Protonated molecular peptide ions and their product ions generated by tandem mass spectrometry appear as isotopologue clusters due to the natural isotopic variations of carbon, hydrogen, nitrogen, oxygen and sulfur. Quantitation of the isotopic composition of peptides can be employed in experiments involving isotope effects, isotope exchange, isotopic labeling by chemical reactions, and studies of metabolism by stable isotope incorporation. Both ion trap and quadrupole-time of flight mass spectrometry are shown to be capable of determining the isotopic composition of peptide product ions obtained by tandem mass spectrometry with both precision and accuracy. Tandem mass spectra obtained in profile-mode of clusters of isotopologue ions are fit by non-linear least squares to a series of Gaussian peaks (described in the accompanying manuscript) which quantify the Mn/M0 values which define the isotopologue distribution (ID). To determine the isotopic composition of product ions from their ID, a new algorithm that predicts the Mn/M0 ratios is developed which obviates the need to determine the intensity of all of the ions of an ID. Consequently a precise and accurate determination of the isotopic composition a product ion may be obtained from only the initial values of the ID, however the entire isotopologue cluster must be isolated prior to fragmentation. Following optimization of the molecular ion isolation width, fragmentation energy and detector sensitivity, the presence of isotopic excess (2H, 13C, 15N, 18O) is readily determined within 1%. The ability to determine the isotopic composition of sequential product ions permits the isotopic composition of individual amino acid residues in the precursor ion to be determined. PMID:17559791
Sharmin, Nusrat; Hasan, Muhammad S; Parsons, Andrew J; Rudd, Chris D; Ahmed, Ifty
2016-06-01
In this study, Polylactic acid (PLA)/phosphate glass fibres (PGF) composites were prepared by compression moulding. Fibres produced from phosphate based glasses P2O5-CaO-MgO-Na2O (P45B0), P2O5-CaO-MgO-Na2O-B2O3 (P45B5), P2O5-CaO-MgO-Na2O-Fe2O3 (P45Fe3) and P2O5-CaO-MgO-Na2O-B2O3-Fe2O3 (P45B5Fe3) were used to reinforce the bioresorbable polymer PLA. Fibre mechanical properties and degradation rate were investigated, along with the mechanical properties, degradation and cytocompatibility of the composites. Retention of the mechanical properties of the composites was evaluated during degradation in PBS at 37°C for four weeks. The fibre volume fraction in the composite varied from 19 to 23%. The flexural strength values (ranging from 131 to 184MPa) and modulus values (ranging from 9.95 to 12.29GPa) obtained for the composites matched those of cortical bone. The highest flexural strength (184MPa) and modulus (12.29GPa) were observed for the P45B5Fe3 composite. After 28 days of immersion in PBS at 37°C, ~35% of the strength profile was maintained for P45B0 and P45B5 composites, while for P45Fe3 and P45B5Fe3 composites ~40% of the initial strength was maintained. However, the overall wet mass change of P45Fe3 and P45B5Fe3 remained significantly lower than that of the P45B0 and P45B5 composites. The pH profile also revealed that the P45B0 and P45B5 composites degraded quicker, correlating well with the degradation profile. From SEM analysis, it could be seen that after 28 days of degradation, the fibres in the fractured surface of P45B5Fe3 composites remain fairly intact as compared to the other formulations. The in vitro cell culture studies using MG63 cell lines revealed both P45Fe3 and P45B5Fe3 composites maintained and showed higher cell viability as compared to the P45B0 and P45B5 composites. This was attributed to the slower degradation rate of the fibres in P45Fe3 and P45B5Fe3 composites as compared with the fibres in P45B0 and P45B5 composites. Copyright © 2015 Elsevier Ltd. All rights reserved.
Liu, Xiaoling; Hasan, Muhammad S; Grant, David M; Harper, Lee T; Parsons, Andrew J; Palmer, Graham; Rudd, Chris D; Ahmed, Ifty
2014-11-01
Retention of mechanical properties of phosphate glass fibre reinforced degradable polyesters such as polycaprolactone and polylactic acid in aqueous media has been shown to be strongly influenced by the integrity of the fibre/polymer interface. A previous study utilising 'single fibre' fragmentation tests found that coating with magnesium improved the fibre and matrix interfacial shear strength. Therefore, the aim of this study was to investigate the effects of a magnesium coating on the manufacture and characterisation of a random chopped fibre reinforced polycaprolactone composite. Short chopped strand non-woven phosphate glass fibre mats were sputter coated with degradable magnesium to manufacture phosphate glass fibre/polycaprolactone composites. The degradation behaviour (water uptake, mass loss and pH change of the media) of these polycaprolactone composites as well as of pure polycaprolactone was investigated in phosphate buffered saline. The Mg coated fibre reinforced composites revealed less water uptake and mass loss during degradation compared to the non-coated composites. The cations released were also explored and a lower ion release profile for all three cations investigated (namely Na(+), Mg(2+) and Ca(2+)) was seen for the Mg coated composite samples. An increase of 17% in tensile strength and 47% in tensile modulus was obtained for the Mg coated composite samples. Both flexural and tensile properties were investigated and a higher retention of mechanical properties was obtained for the Mg coated fibre reinforced composite samples up to 10 days immersion in PBS. Cytocompatibility study showed both composite samples (coated and non-coated) had good cytocompatibility with human osteosarcoma cell line. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Gonzalez-Fernandez, Oscar; Queralt, Ignacio
2010-09-01
Elemental analysis of different sediment cores originating from the Cartagena-La Union mining district in Spain was carried out by means of a programmable small-spot energy-dispersive X-ray fluorescence (EDXRF) spectrometer to study the distribution of heavy metals along soil profiles. Cores were obtained from upstream sediments of a mining creek, from the lowland sedimentation plain, and from a mining landfill dump (tailings pile). A programmable two-dimensional (2D) stage and a focal spot resolution of 600 μm allow us to obtain complete core mapping. Geochemical results were verified using a more powerful wavelength-dispersion X-ray fluorescence (WDXRF) technique. The data obtained was processed in order to study the statistical correlations within the elemental compositions. The results obtained allow us to observe the differential in-depth distribution of heavy metals among the sampled zones. Dump site cores exhibit a homogeneous distribution of heavy metals, whereas the alluvial plain core shows accumulation of heavy metals in the upper part. This approach can be useful for the fast screening of heavy metals in depositional environments around mining sites.
Sediment characteristic on hydropower plant Bakaru, South Sulawesi
NASA Astrophysics Data System (ADS)
Firman, Yunus, A. M. Shiddiq; Yunus, M. Yusuf
2017-01-01
This research is aimed to determine the distributed sediment composition and its size particle impact on flow profile in the pipe. The sediment sample is collected from Hydropower Plant's dam located at Bakaru Sulawesi Selatan. The sample is dried in the oven then steered up using a screen with 0.25; 0.5; and 0.75 mm. Sediment identification is measured using Fourier Transform Infrared Spectrophotometer (FTIR) and X-Ray Fluorescence Spectrophotometer (XRF). The assessment of flow type in the pipe with five flow rate variation for every single sediment diameter is assessed in Fluid Measurement Laboratory under Mechanical Engineering Department, State Polytechnic of Ujung Pandang. As a result of steered up processed, it is obtained that the sediment distribution with diameter of ø = 0.25 mm is 55.80%; for ø = 0.5 mm is 7.91%; and ø = 0.75 mm is 36.29%. From FTIR test, it is obtained the spectra with wave number of 466.77; 536.14; 644.22; 694.37; 788.89; 912.33; 1006.77; 1031.92; and 105.21 cm-1. From XRF assessment, it can be obtained that composition of SiO2 is 53.64%, Al2O3 is 22.93%, Fe2O3 is 9.24%, MgO is 4.0%, K2O is 3.84%, Na2O is 2.4%, CaO is 1.71%, and TiO2 is 1.06%. From the flow profile assessment, it obtains Reynolds number is lesser than 500 for these three particle diameters variation. It can be concluded that sediment characteristic consists of fine sand about 55.80% and coarse sand about 44.20%, where SiO2 dominates it by about 53.64% where flow in the pipe shown the laminar type.
Ping, Bonnie Tay Yen; Aziz, Haliza Abdul; Idris, Zainab
2018-01-01
High-Performance Liquid Chromatography (HPLC) methods via evaporative light scattering (ELS) and refractive index (RI) detectors are used by the local palm oil industry to monitor the TAG profiles of palm oil and its fractions. The quantitation method used is based on area normalization of the TAG components and expressed as percentage area. Although not frequently used, peak-area ratios based on TAG profiles are a possible qualitative method for characterizing the TAG of palm oil and its fractions. This paper aims to compare these two detectors in terms of peak-area ratio, percentage peak area composition, and TAG elution profiles. The triacylglycerol (TAG) composition for palm oil and its fractions were analysed under similar HPLC conditions i.e. mobile phase and column. However, different sample concentrations were used for the detectors while remaining within the linearity limits of the detectors. These concentrations also gave a good baseline resolved separation for all the TAGs components. The results of the ELSD method's percentage area composition for the TAGs of palm oil and its fractions differed from those of RID. This indicates an unequal response of TAGs for palm oil and its fractions using the ELSD, also affecting the peak area ratios. They were found not to be equivalent to those obtained using the HPLC-RID. The ELSD method showed a better baseline separation for the TAGs components, with a more stable baseline as compared with the corresponding HPLC-RID. In conclusion, the percentage area compositions and peak-area ratios for palm oil and its fractions as derived from HPLC-ELSD and RID were not equivalent due to different responses of TAG components to the ELSD detector. The HPLC-RID has a better accuracy for percentage area composition and peak-area ratio because the TAG components response equally to the detector.
NASA Technical Reports Server (NTRS)
Shevade, A. V.; Ryan, M. A.; Homer, M. L.; Manfreda, A. M.; Zhou, H.; Manatt, K.
2002-01-01
We report a molecular modeling study to investigate the polymer-carbon black (CB) composite-analyte interactions in resistive sensors. These sensors comprise the JPL Electronic Nose (ENose) sensing array developed for monitoring breathing air in human habitats. The polymer in the composite is modeled based on its stereisomerism and sequence isomerism, while the CB is modeled as uncharged naphthalene rings (with no hydrogens). The Dreiding 2.21 force field is used for the polymer and solvent molecules and graphite parameters are assigned to the carbon black atoms. A combination of molecular mechanics (MM) and molecular dynamics (NPT-MD and NVT-MD) techniques are used to obtain the equilibrium composite structure by inserting naphthalene rings in the polymer matrix. Polymers considered for this work include poly(4- vinylphenol), polyethylene oxide, and ethyl cellulose. Analytes studied are representative of both inorganic (ammonia) and organic (methanol, toluene, hydrazine) compounds. The results are analyzed for the composite microstructure by calculating the radial distribution profiles as well as for the sensor response by predicting the interaction energies of the analytes with the composites.
Molecular modeling of polymer composite-analyte interactions in electronic nose sensors
NASA Technical Reports Server (NTRS)
Shevade, A. V.; Ryan, M. A.; Homer, M. L.; Manfreda, A. M.; Zhou, H.; Manatt, K. S.
2003-01-01
We report a molecular modeling study to investigate the polymer-carbon black (CB) composite-analyte interactions in resistive sensors. These sensors comprise the JPL electronic nose (ENose) sensing array developed for monitoring breathing air in human habitats. The polymer in the composite is modeled based on its stereoisomerism and sequence isomerism, while the CB is modeled as uncharged naphthalene rings with no hydrogens. The Dreiding 2.21 force field is used for the polymer, solvent molecules and graphite parameters are assigned to the carbon black atoms. A combination of molecular mechanics (MM) and molecular dynamics (NPT-MD and NVT-MD) techniques are used to obtain the equilibrium composite structure by inserting naphthalene rings in the polymer matrix. Polymers considered for this work include poly(4-vinylphenol), polyethylene oxide, and ethyl cellulose. Analytes studied are representative of both inorganic and organic compounds. The results are analyzed for the composite microstructure by calculating the radial distribution profiles as well as for the sensor response by predicting the interaction energies of the analytes with the composites. c2003 Elsevier Science B.V. All rights reserved.
Design and performance of a shape memory alloy-reinforced composite aerodynamic profile
NASA Astrophysics Data System (ADS)
Simpson, J. C.; Boller, C.
2008-04-01
Based on a shape memory alloy (SMA)-reinforced composite developed separately, the applicability of the composite has been demonstrated through realization of a realistically scaled aerodynamic profile of around 0.5 m span by 0.5 m root chord whose skins had been made from this composite. The design, manufacturing and assembly of the profile are described. The curved skins were manufactured with two layers of SMA wires integrated into the layup of aramid fibre prepregs. All SMA wires were connected such that they can be operated as individual sets of wires and at low voltages, similar to the conditions for electrical energy generation in a real aircraft. The profile was then mounted on a vibration test rig and excited by a shaker at its tip which allowed the dynamic performance of the profile to be validated under internal actuation conditions generated through the SMA wires.
Modahl, Cassandra M.; Mackessy, Stephen P.
2016-01-01
Envenomation of humans by snakes is a complex and continuously evolving medical emergency, and treatment is made that much more difficult by the diverse biochemical composition of many venoms. Venomous snakes and their venoms also provide models for the study of molecular evolutionary processes leading to adaptation and genotype-phenotype relationships. To compare venom complexity and protein sequences, venom gland transcriptomes are assembled, which usually requires the sacrifice of snakes for tissue. However, toxin transcripts are also present in venoms, offering the possibility of obtaining cDNA sequences directly from venom. This study provides evidence that unknown full-length venom protein transcripts can be obtained from the venoms of multiple species from all major venomous snake families. These unknown venom protein cDNAs are obtained by the use of primers designed from conserved signal peptide sequences within each venom protein superfamily. This technique was used to assemble a partial venom gland transcriptome for the Middle American Rattlesnake (Crotalus simus tzabcan) by amplifying sequences for phospholipases A2, serine proteases, C-lectins, and metalloproteinases from within venom. Phospholipase A2 sequences were also recovered from the venoms of several rattlesnakes and an elapid snake (Pseudechis porphyriacus), and three-finger toxin sequences were recovered from multiple rear-fanged snake species, demonstrating that the three major clades of advanced snakes (Elapidae, Viperidae, Colubridae) have stable mRNA present in their venoms. These cDNA sequences from venom were then used to explore potential activities derived from protein sequence similarities and evolutionary histories within these large multigene superfamilies. Venom-derived sequences can also be used to aid in characterizing venoms that lack proteomic profiles and identify sequence characteristics indicating specific envenomation profiles. This approach, requiring only venom, provides access to cDNA sequences in the absence of living specimens, even from commercial venom sources, to evaluate important regional differences in venom composition and to study snake venom protein evolution. PMID:27280639
Auger analysis of a fiber/matrix interface in a ceramic matrix composite
NASA Technical Reports Server (NTRS)
Honecy, Frank S.; Pepper, Stephen V.
1988-01-01
Auger electron spectroscopy (AES) depth profiling was used to characterize the fiber/matrix interface of an SiC fiber, reaction bonded Si3N4 matrix composite. Depth profiles of the as received double coated fiber revealed concentration oscillations which disappeared after annealing the fiber in the environment used to fabricate the composite. After the composite was fractured, the Auger depth profiles showed that failure occurred in neither the Beta-SiC fiber body nor in the Si3N4 matrix but, concurrently, at the fiber coating/matrix interface and within the fiber coating itself.
NASA Astrophysics Data System (ADS)
Paulraj, D.; Swamynathan, S.; Madhaiyan, M.
2012-11-01
Web Service composition has become indispensable as a single web service cannot satisfy complex functional requirements. Composition of services has received much interest to support business-to-business (B2B) or enterprise application integration. An important component of the service composition is the discovery of relevant services. In Semantic Web Services (SWS), service discovery is generally achieved by using service profile of Ontology Web Languages for Services (OWL-S). The profile of the service is a derived and concise description but not a functional part of the service. The information contained in the service profile is sufficient for atomic service discovery, but it is not sufficient for the discovery of composite semantic web services (CSWS). The purpose of this article is two-fold: first to prove that the process model is a better choice than the service profile for service discovery. Second, to facilitate the composition of inter-organisational CSWS by proposing a new composition method which uses process ontology. The proposed service composition approach uses an algorithm which performs a fine grained match at the level of atomic process rather than at the level of the entire service in a composite semantic web service. Many works carried out in this area have proposed solutions only for the composition of atomic services and this article proposes a solution for the composition of composite semantic web services.
Avizcuri-Inac, José-Miguel; Gonzalo-Diago, Ana; Sanz-Asensio, Jesús; Martínez-Soria, María-Teresa; López-Alonso, Miguel; Dizy-Soto, Marta; Echávarri-Granado, José-Federico; Vaquero-Fernández, Luis; Fernández-Zurbano, Purificación
2013-02-06
The overall objective of this study was to investigate the effect of manual cluster thinning (CT) and the application of the growth regulator Prohexadione calcium (ProCa) on the phenolic composition and the sensory profile of Tempranillo and Grenache wines produced from treated vines in La Rioja (Spain). ProCa was applied at preblooming and CT was carried out at veraison in two consecutive years. Different physicochemical parameters and analyses of phenolic compounds were carried out in control, CT and ProCa grapes and wines and wine sensory was performed. Thinning treatments decreased crop yield, besides ProCa application reduced berry size, and berry weight. Color and phenolic composition of Grenache and Tempranillo wines in general were affected by thinning treatments, with an increase in anthocyanin, flavanol and flavonol concentrations. In sensory analysis, wines obtained from thinned vines presented higher values for several aromatic (e.g., white and yellow fruits, fresh flowers) and taste attributes (i.e., astringency, bitternes, persistence). CT and ProCa treatments resulted in an improvement in wine quality. In general, similar results in phenolic composition, sensory properties and quality of wines were obtained by manual and chemical cluster thinning. ProCa as a growth regulator may be an option for a quality vitiviniculture.
NASA Astrophysics Data System (ADS)
Wemheuer, Franziska; Kaiser, Kristin; Karlovsky, Petr; Daniel, Rolf; Vidal, Stefan; Wemheuer, Bernd
2017-01-01
Endophytic bacteria are critical for plant growth and health. However, compositional and functional responses of bacterial endophyte communities towards agricultural practices are still poorly understood. Hence, we analyzed the influence of fertilizer application and mowing frequency on bacterial endophytes in three agriculturally important grass species. For this purpose, we examined bacterial endophytic communities in aerial plant parts of Dactylis glomerata L., Festuca rubra L., and Lolium perenne L. by pyrotag sequencing of bacterial 16S rRNA genes over two consecutive years. Although management regimes influenced endophyte communities, observed responses were grass species-specific. This might be attributed to several bacteria specifically associated with a single grass species. We further predicted functional profiles from obtained 16S rRNA data. These profiles revealed that predicted abundances of genes involved in plant growth promotion or nitrogen metabolism differed between grass species and between management regimes. Moreover, structural and functional community patterns showed no correlation to each other indicating that plant species-specific selection of endophytes is driven by functional rather than phylogenetic traits. The unique combination of 16S rRNA data and functional profiles provided a holistic picture of compositional and functional responses of bacterial endophytes in agricultural relevant grass species towards management practices.
Monggoot, Sakon; Kulsing, Chadin; Wong, Yong Foo; Pripdeevech, Patcharee
2018-06-01
Incubation with microbial culture supernatants improved essential oil yield from Aquilaria subintegra woodchips. The harvested woodchips were incubated with de man, rogosa and sharpe (MRS) agar, yeast mold (YM) agar medium and six different microbial culture supernatants obtained from Lactobacillus bulgaricus , L. acidophilus , Streptococcus thermophilus , Lactococcus lactis , Saccharomyces carlsbergensis and S. cerevisiae prior to hydrodistillation. Incubation with lactic acid bacteria supernatants provided higher yield of agarwood oil (0.45% w/w) than that obtained from yeast (0.25% w/w), agar media (0.23% w/w) and water (0.22% w/w). The composition of agarwood oil from all media and microbial supernatant incubations was investigated by using gas chromatography-mass spectrometry. Overall, three major volatile profiles were obtained, which corresponded to water soaking (control), as well as, both YM and MRS media, lactic acid bacteria, and yeast supernatant incubations. Sesquiterpenes and their oxygenated derivatives were key components of agarwood oil. Fifty-two volatile components were tentatively identified in all samples. Beta-agarofuran, α-eudesmol, karanone, α-agarofuran and agarospirol were major components present in most of the incubated samples, while S. cerevisiae -incubated A. subintegra provided higher amount of phenyl acetaldehyde. Microbial culture supernatant incubation numerically provided the highest yield of agarwood oil compared to water soaking traditional method, possibly resulting from activity of extracellular enzymes produced by the microbes. Incubation of agarwood with lactic acid bacteria supernatant significantly enhanced oil yields without changing volatile profile/composition of agarwood essential oil, thus this is a promising method for future use.
STEROL PROFILES IN 18 MACROALGAE OF THE PORTUGUESE COAST(1).
Lopes, Graciliana; Sousa, Carla; Bernardo, João; Andrade, Paula B; Valentão, Patrícia; Ferreres, Federico; Mouga, Teresa
2011-10-01
The sterol profiles of dominant macroalgae occurring in the western Portuguese coast were evaluated. An analytical procedure, involving alkaline hydrolysis and extraction followed by separation by reversed-phase HPLC-diode array detection (HPLC-DAD), was optimized for the study of their sterols composition. The validated methodology is short in analysis time (as the compounds are determined in <20 min), sensitive, reproducible, and accurate. It was then successfully applied to the determination of campesterol, cholesterol, desmosterol, ergosterol, fucosterol, stigmasterol, and β-sitosterol in 18 species (three Chlorophyta, five Rhodophyta, and 10 Phaeophyta). The profiles obtained for the several macroalgal species were considerably different. C29 sterols were predominant in Phaeophyta and Chlorophyta (71%-95% of total sterol content), while in Rhodophyta cholesterol content is significantly higher (34%-87%). Among the studied species, Asparagopsis armata Harv. contained the lowest sterol amount (555 mg · kg(-1) dry weight), and Cystoseira tamariscifolia (Huds.) Papenf. the highest one (6,502 mg · kg(-1) dry weight). Data obtained may be helpful in identifying suitable marine sources of sterols, with potential applications in the food and pharmaceutical industries. © 2011 Phycological Society of America.
Highly porous drug-eluting structures
Elsner, Jonathan J.; Kraitzer, Amir; Grinberg, Orly; Zilberman, Meital
2012-01-01
For many biomedical applications, there is need for porous implant materials. The current article focuses on a method for preparation of drug-eluting porous structures for various biomedical applications, based on freeze drying of inverted emulsions. This fabrication process enables the incorporation of any drug, to obtain an “active implant” that releases drugs to the surrounding tissue in a controlled desired manner. Examples for porous implants based on this technique are antibiotic-eluting mesh/matrix structures used for wound healing applications, antiproliferative drug-eluting composite fibers for stent applications and local cancer treatment, and protein-eluting films for tissue regeneration applications. In the current review we focus on these systems. We show that the release profiles of both types of drugs, water-soluble and water-insoluble, are affected by the emulsion's formulation parameters. The former's release profile is affected mainly through the emulsion stability and the resulting porous microstructure, whereas the latter's release mechanism occurs via water uptake and degradation of the host polymer. Hence, appropriate selection of the formulation parameters enables to obtain desired controllable release profile of any bioactive agent, water-soluble or water-insoluble, and also fit its physical properties to the application. PMID:23507890
Bajoub, Aadil; Medina-Rodríguez, Santiago; Olmo-García, Lucía; Ajal, El Amine; Monasterio, Romina P.; Hanine, Hafida; Fernández-Gutiérrez, Alberto; Carrasco-Pancorbo, Alegría
2016-01-01
Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars (“Picholine Marocaine”, “Dahbia”, “Haouzia” and “Menara”), and nine Mediterranean varieties recently introduced in Morocco (“Arbequina”, “Arbosana”, “Cornicabra”, “Frantoio”, “Hojiblanca”, “Koroneiki”, “Manzanilla”, “Picholine de Languedoc” and “Picual”), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils. PMID:28036024
NASA Technical Reports Server (NTRS)
Fink, J.; Zimbelman, J.
1985-01-01
Theoretical models used in the remote determination of lava flow rheology and compositions rely on estimates of such geometric and flow parameters as volume flow rates, levee heights, and channel dimensions, as well as morphologic and structural patterns on the flow surfaces. Quantitative measures of these variables are difficult to obtain, even under optimum conditions. Detailed topographic profiles across several Hawaiian lava flows that were carefully monitored by the U.S. Geological Survey during their emplacement in 1983 were surveyed in order to test various flow emplacement models. Twenty two accurate channel cross sections were constructed by combining these profiles with digitized pre-flow topographic measurements. Levee heights, shear zone widths, and flow depths could then be read directly from the cross sections and input into the models. The profiles were also compared with ones constructed for some Martian lava flows.
Io plasma torus ion composition: Voyager, Galileo, and Cassini
NASA Astrophysics Data System (ADS)
Nerney, Edward G.; Bagenal, Fran; Steffl, Andrew J.
2017-01-01
The Io torus produces ultraviolet emissions diagnostic of plasma conditions. We revisit data sets obtained by the Voyager 1, Galileo, and Cassini missions at Jupiter. With the latest version (8.0) of the CHIANTI atomic database we analyze UV spectra to determine ion composition. We compare ion composition obtained from observations from these three missions with a theoretical model of the physical chemistry of the torus by Delamere et al. (2005). We find ion abundances from the Voyager data similar to the Cassini epoch, consistent with the dissociation and ionization of SO2, but with a slightly higher average ionization state for sulfur, consistent with the higher electron temperature measured by Voyager. This reanalysis of the Voyager data produces a much lower oxygen:sulfur ratio than earlier analysis by Shemansky (1988), which was also reported by Bagenal (1994). We derive fractional ion compositions in the center of the torus to be S+/Ne 5%, S++/Ne 20%, S+++/Ne 5%, O+/Ne 20%, O++/Ne 3%, and Σ(On+)/Σ(Sn+) 0.8, leaving about 10-15% of the charge as protons. The radial profile of ion composition indicates a slightly higher average ionization state, a modest loss of sulfur relative to oxygen, and Σ(On+)/Σ(Sn+) 1.2 at about 8 RJ, beyond which the composition is basically frozen in. The Galileo observations of UV emissions from the torus suggest that the composition in June 1996 may have comprised a lower abundance of oxygen than usual, consistent with observations made at the same time by the EUVE satellite.
Yi, Y; Birks, S J; Cho, S; Gibson, J J
2015-06-15
This study was conducted to characterize the composition of dissolved organic compounds present in snow and surface waters in the Athabasca Oil Sands Region (AOSR) with the goal of identifying whether atmospherically-derived organic compounds present in snow are a significant contributor to the compounds detected in surface waters (i.e., rivers and lakes). We used electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR MS) to characterize the dissolved organic compound compositions of snow and surface water samples. The organic profiles obtained for the snow samples show compositional differences between samples from near-field sites (<5 km from oil sands activities) and those from more distant locations (i.e., far-field sites). There are also significant compositional differences between samples collected in near-field sites and surface water samples in the AOSR. The composition of dissolved organic compounds at the upstream Athabasca River site (i.e., Athabasca River at Athabasca) is found to be different from samples obtained from downstream sites in the vicinity of oil sands operations (i.e., Athabasca River at Fort McMurray and Athabasca River at Firebag confluence). The upstream Athabasca River sites tended to share some compositional similarities with far-field snow deposition, while the downstream Athabasca River sites are more similar to local lakes and tributaries. This contrast likely indicates the relative role of regional snowmelt contributions to the Athabasca River vs inputs from local catchments in the reach downstream of Fort McMurray. Copyright © 2015 Elsevier B.V. All rights reserved.
Persistence of immersed blood and hair DNA: A preliminary study based on casework.
Frippiat, Christophe; Gastaldi, Agathe; Van Grunderbeeck, Séverine
2017-10-01
In some cases, evidence is collected from rivers, canals, lakes or sink pipes. To determine the utility of analyzing these samples and for cases in which DNA was recovered from submerged bulletproof vest parts, we evaluated the time necessary to degrade the blood and, subsequently, DNA on bulletproof vests. In a second experiment, also based on cases, blood was diluted in water from a kitchen sink pipe and incubated at room temperature for different times. Subsequently, DNA quality was assessed. In a parallel experiment, hair roots were incubated in spring water for different time periods. This study demonstrates that after one week of immersion of the bulletproof vest parts in a canal only one sample from more than 100 samples gave a partial genetic profile. No genetic profile were obtained for the 99 other samples. After one month immersion and despite the finding that blood remained detectable on bulletproof vest parts, no genetic profile was obtained for all samples using the classical STR approach. For longer immersion times, no genetic profiles were obtained. In sink pipe water, an incubation time of 72 h (h) was necessary before significant blood degradation occurred. Nevertheless, high inter-sample variability was observed. This high variability may be explained by the variability of water composition coming from nine different sink pipes. For hair root cells incubated in water, we observed that more than 90% of the DNA was degraded after 72 h. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Fabrication of a Mo based high temperature TZM alloy by non-consumable arc melting technique
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chakraborty, S.P.; Krishnamurthy, N., E-mail: spc@barc.gov.in
High temperature structural materials are in great demand for power, chemical and nuclear industries which can perform beyond 1000 °C as super alloys usually fail. In this regard, Mo based TZM alloy is capable of retaining strength up to 1500 °C with excellent corrosion compatibility against molten alkali metals. Hence, currently this alloy is considered an important candidate material for high temperature compact nuclear and fusion reactors. Due to reactive nature of Mo and having high melting point, manufacturing this alloy by conventional process is unsuitable. Powder metallurgy technique has limited success due to restriction in quantity and purity. Thismore » paper deals with fabrication of TZM alloy by nonconsumable tungsten arc melting technique. Initially a ternary master alloy of Mo-Ti-Zr was prepared which subsequently by dilution method, was converted into TZM alloy gradually by external addition of Mo and C in various proportions. A number of melting trials were conducted to optimize the process parameters like current, voltage and time to achieve desired alloy composition. The alloy was characterized with respect to composition, elemental distribution profile, microstructure, hardness profile and phase analysis. Well consolidated alloy button was obtained having desired composition, negligible material loss and having microstructure as comparable to standard TZM alloy. (author)« less
Xu, X.; Sumption, M. D.
2016-01-12
In this work we explore the compositions of non-stoichiometric intermediate phases formed by diffusion reactions: a mathematical framework is developed and tested against the specific case of Nb 3Sn superconductors. In the first part, the governing equations for the bulk diffusion and interphase interface reactions during the growth of a compound are derived, numerical solutions to which give both the composition profile and growth rate of the compound layer. The analytic solutions are obtained with certain approximations made. In the second part, we explain an effect that the composition characteristics of compounds can be quite different depending on whether itmore » is the bulk diffusion or grain boundary diffusion that dominates in the compounds, and that “frozen” bulk diffusion leads to unique composition characteristics that the bulk composition of a compound layer remains unchanged after its initial formation instead of varying with the diffusion reaction system; here the model is modified for the case of grain boundary diffusion. Lastly, we apply this model to the Nb 3Sn superconductors and propose approaches to control their compositions.« less
Tsiplakou, Eleni; Kotrotsios, Vaios; Hadjigeorgiou, Ioannis; Zervas, George
2010-08-01
The objective of this study was to investigate whether there is a difference in chemical composition and particularly in fatty acid (FA) profile, with emphasis on cis-9, trans-11 CLA, of milk obtained from conventional and organic dairy sheep and goats farms under the farming conditions practiced in Greece. Four dairy sheep and four dairy goat farms, representing common conventional production systems and another four dairy sheep and four dairy goat farms, organically certified, representing organic production and feeding systems were selected from all over Greece. One hundred and sixty two individual milk samples were collected from those farms in January-February 2009, about three months after parturition. The milk samples were analyzed for their main chemical constituents and their FA profile. The results showed that the production system affected milk chemical composition: in particular fat content was lower in the organic sheep and goats milk compared with the corresponding conventional. Milk from organic sheep had higher content in MUFA, PUFA, alpha-LNA, cis-9, trans-11 CLA, and omega-3 FA, whereas in milk from organic goats alpha-LNA and omega-3 FA content was higher than that in conventional one. These differences are, mainly, attributed to different feeding practices used by the two production systems. The results of this study show that the organic milk produced under the farming conditions practiced in Greece has higher nutritional value, due to its FA profile, compared with the respective conventional milk.
Escobar Galindo, Ramón; Gago, Raul; Duday, David; Palacio, Carlos
2010-04-01
An increasing amount of effort is currently being directed towards the development of new functionalized nanostructured materials (i.e., multilayers and nanocomposites). Using an appropriate combination of composition and microstructure, it is possible to optimize and tailor the final properties of the material to its final application. The analytical characterization of these new complex nanostructures requires high-resolution analytical techniques that are able to provide information about surface and depth composition at the nanometric level. In this work, we comparatively review the state of the art in four different depth-profiling characterization techniques: Rutherford backscattering spectroscopy (RBS), secondary ion mass spectrometry (SIMS), X-ray photoelectron spectroscopy (XPS) and glow discharge optical emission spectroscopy (GDOES). In addition, we predict future trends in these techniques regarding improvements in their depth resolutions. Subnanometric resolution can now be achieved in RBS using magnetic spectrometry systems. In SIMS, the use of rotating sample holders and oxygen flooding during analysis as well as the optimization of floating low-energy ion guns to lower the impact energy of the primary ions improves the depth resolution of the technique. Angle-resolved XPS provides a very powerful and nondestructive technique for obtaining depth profiling and chemical information within the range of a few monolayers. Finally, the application of mathematical tools (deconvolution algorithms and a depth-profiling model), pulsed sources and surface plasma cleaning procedures is expected to greatly improve GDOES depth resolution.
NASA Astrophysics Data System (ADS)
Mareschal, J.; Jaupart, C. P.
2013-12-01
Most of the variations in surface heat flux in stable continents are caused by variations in crustal heat production, with an almost uniform heat flux at the base of the crust ( 15+/-3 mW/m2). Such relatively small differences in Moho heat flux cannot be resolved by heat flow data alone, but they lead to important lateral variations in lithospheric temperatures and thicknesses. In order to better constrain temperatures in the lower lithosphere, we have combined surface heat flow and heat production data from the southern Superior Province in Canada with vertical shear wave velocity profiles obtained from surface wave inversion. We use the Monte-Carlo method to generate lithospheric temperature profiles from which shear wave velocity can be calculated for a given mantle composition. We eliminate thermal models which yield lithospheric and sub-lithospheric velocities that do not fit the shear wave velocity profile. Surface heat flux being constrained, the free parameters of the thermal model are: the mantle heat flux, the mantle heat production, the crustal differentiation index (ratio of surface to bulk crustal heat production) and the temperature of the mantle isentrope. Two conclusions emerge from this study. One is that, for some profiles, the vertical variations in shear wave velocities cannot be accounted for by temperature alone but also require compositional changes within the lithosphere. The second is that there are long wavelength horizontal variations in mantle temperatures (~80-100K) at the base of the lithosphere and in the mantle below
Infusions of artichoke and milk thistle represent a good source of phenolic acids and flavonoids.
Pereira, Carla; Barros, Lillian; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C F R
2015-01-01
Cynara scolymus L. (artichoke) and Silybum marianum (L.) Gaertn (milk thistle) are two herbs well-known for their efficiency in the prevention/treatment of liver injuries, among other chronic diseases. Therefore, the aim of this work was to characterize specific bioactive components, phenolic compounds, in hydromethanolic extracts but also in infusions (the most commonly used preparations) obtained from the whole plant of milk thistle and artichoke. The phenolic profiles were accessed using HPLC-DAD-MS/ESI. Infusions of both species presented higher phenolic contents than the hydromethanolic extracts. Milk thistle presented a similar phenolic composition between the two preparations, revealing only differences in the quantities obtained. Nevertheless, artichoke revealed a slightly different profile considering infusion and hydromethanolic extracts. Apigenin-7-O-glucuronide was the major flavonoid found in milk thistle, while luteolin-7-O-glucuronide was the most abundant in artichoke. Therefore, infusions of both artichoke and milk thistle represent a good source of bioactive compounds, especially phenolic acids and flavonoids.
Microdialysis as a New Technique for Extracting Phenolic Compounds from Extra Virgin Olive Oil.
Bazzu, Gianfranco; Molinu, Maria Giovanna; Dore, Antonio; Serra, Pier Andrea
2017-03-01
The amount and composition of the phenolic components play a major role in determining the quality of olive oil. The traditional liquid-liquid extraction (LLE) method requires a time-consuming sample preparation to obtain the "phenolic profile" of extra virgin olive oil (EVOO). This study aimed to develop a microdialysis extraction (MDE) as an alternative to the LLE method to evaluate the phenolic components of EVOO. To this purpose, a microdialysis device and dialysis procedure were developed. "Dynamic-oil" microdialysis was performed using an extracting solution (80:20 methanol/water) flow rate of 2 μL min -1 and a constant EVOO stream of 4 μL min -1 . The results indicated a strong positive correlation between MDE and the LLE method, providing a very similar phenolic profile obtained with traditional LLE. In conclusion, the MDE approach, easier and quicker in comparison to LLE, provided a reliable procedure to determine the phenolic components used as a marker of the quality and traceability of EVOO.
Purification and protein composition of endogenous rat viruses.
Hlubinová, K; Prachar, J; Vrbenská, A; Matoska, J; Simkovic, D
1984-01-01
Endogenous retroviruses are not in the majority of cases the cause of any neoplasia, except for the laboratory conditions. As far as they might serve for the evolution of pathogenic retroviruses more attention should have been paid to them. In this paper we introduce some approaches to the purification of rat endogenous retroviruses to such a degree of purity that enabled satisfactory SDS-PAGE analysis of its structural proteins. Purities of samples obtained by usual purification methods, long-term isopycnic centrifugation at a high gravity force and velocity centrifugation are compared. Protein profile of rat endogenous virus in SDS-PAGE is compared with the ones of other retroviruses. For the first time the evidence was obtained for the striking similarity between electrophoretic protein profile of rat endogenous virus WERC and feline leukemia virus. The major structural proteins of rat endogenous retrovirus and feline leukemia virus cannot be distinguished even when resolution long gradient PAGE had been employed. The accordance of electrophoretic mobilities of major structural proteins in SDS-PAGE can indicate the relatedness of retroviruses.
Compositional control of continuously graded anode functional layer
NASA Astrophysics Data System (ADS)
McCoppin, J.; Barney, I.; Mukhopadhyay, S.; Miller, R.; Reitz, T.; Young, D.
2012-10-01
In this work, solid oxide fuel cells (SOFC's) are fabricated with linear-compositionally graded anode functional layers (CGAFL) using a computer-controlled compound aerosol deposition (CCAD) system. Cells with different CGAFL thicknesses (30 um and 50 um) are prepared with a continuous compositionally graded interface deposited between the electrolyte and anode support current collecting regions. The compositional profile was characterized using energy dispersive X-ray spectroscopic mapping. An analytical model of the compound aerosol deposition was developed. The model predicted compositional profiles for both samples that closely matched the measured profiles, suggesting that aerosol-based deposition methods are capable of creating functional gradation on length scales suitable for solid oxide fuel cell structures. The electrochemical performances of the two cells are analyzed using electrochemical impedance spectroscopy (EIS).
Zhang, De-Long; Zhang, Pei; Zhou, Hao-Jiang; Pun, Edwin Yue-Bun
2008-10-01
We have demonstrated the possibility that near-stoichiometric Ti:LiNbO(3) strip waveguides are fabricated by carrying out vapor transport equilibration at 1060 degrees C for 12 h on a congruent LiNbO(3) substrate with photolithographically patterned 4-8 microm wide, 115 nm thick Ti strips. Optical characterizations show that these waveguides are single mode at 1.5 microm and show a waveguide loss of 1.3 dB/cm for TM mode and 1.1 dB/cm for TE mode. In the width/depth direction of the waveguide, the mode field follows the Gauss/Hermite-Gauss function. Secondary-ion-mass spectrometry (SIMS) was used to study Ti-concentration profiles in the depth direction and on the surface of the 6 microm wide waveguide. The result shows that the Ti profile follows a sum of two error functions along the width direction and a complementary error function in the depth direction. The surface Ti concentration, 1/e width and depth, and mean diffusivities along the width and depth directions of the guide are similar to 3.0 x 10(21) cm(-3), 3.8 microm, 2.6 microm, 0.30 and 0.14 microm(2)/h, respectively. Micro-Raman analysis was carried out on the waveguide endface to characterize the depth profile of Li composition in the guiding layer. The results show that the depth profile of Li composition also follows a complementary error function with a 1/e depth of 3.64 microm. The mean ([Li(Li)]+[Ti(Li)])/([Nb(Nb)]+[Ti(Nb)]) ratio in the waveguide layer is about 0.98. The inhomogeneous Li-composition profile results in a varied substrate index in the guiding layer. A two-dimensional refractive index profile model in the waveguide is proposed by taking into consideration the varied substrate index and assuming linearity between Ti-induced index change and Ti concentration. The net waveguide surface index increments at 1545 nm are 0.0114 and 0.0212 for ordinary and extraordinary rays, respectively. Based upon the constructed index model, the fundamental mode field profile was calculated using the beam propagation method, and the mode sizes and effective index versus the Ti-strip width were calculated for three lower TM and TE modes using the variational method. An agreement between theory and experiment is obtained.
Martínez-Casas, Lucía; Lage-Yusty, María; López-Hernández, Julia
2017-12-13
Black garlic is an elaborated product obtained from fresh garlic (Allium sativum L.) at a controlled high humidity and temperature, which leads to modifications in color, taste, and texture. To clarify the physicochemical changes that occur during the thermal process, this work aimed to evaluate and contrast the antioxidant capacity and that of other compounds between purple garlic ecotype "Purple from Las Pedroñeras" and its black garlic derivative. Our results showed numerous differences between both, because black garlic presented a significant divergence in its volatile profile, a decreased amount of ascorbic acid, an increment in sugar and polyphenol contents, a greater antioxidant capacity, and a different composition of phenolic acids and flavonoids.
NASA Astrophysics Data System (ADS)
Baroni, Travis C.; Griffin, Brendan J.; Browne, James R.; Lincoln, Frank J.
2000-01-01
Charge contrast images (CCI) of synthetic gibbsite obtained on an environmental scanning electron microscope gives information on the crystallization process. Furthermore, X-ray mapping of the same grains shows that impurities are localized during the initial stages of growth and that the resulting composition images have features similar to these observed in CCI. This suggests a possible correlation between impurity distributions and the emission detected during CCI. X-ray line profiles, simulating the spatial distribution of impurities derived from the Monte Carlo program CASINO, have been compared with experimental line profiles and give an estimate of the localization. The model suggests that a main impurity, Ca, is depleted from the solution within approximately 3 4 [mu]m of growth.
BASC-2 PRS profiles for students with high-functioning autism spectrum disorders.
Volker, Martin A; Lopata, Christopher; Smerbeck, Audrey M; Knoll, Valerie A; Thomeer, Marcus L; Toomey, Jennifer A; Rodgers, Jonathan D
2010-02-01
BASC-2 PRS profiles of 62 children with high-functioning autism spectrum disorders (HFASDs) were compared with those of 62 typically-developing children matched by age, gender, and ethnicity. Results indicated that, except for the Somatization, Conduct Problems, and Aggression scales, significant differences were found between the HFASD and typically-developing groups on all PRS scores. Mean HFASD scores were in the clinically significant range on the Behavioral Symptoms Index, Atypicality, Withdrawal, and Developmental Social Disorders scales. At-risk range HFASD means were obtained on the Adaptive Skills composite, all adaptive scales, remaining content scales (except Bullying), and Hyperactivity, Attention Problems, and Depression clinical scales. Screening indices suggested that the Developmental Social Disorders scale was highly effective in differentiating between the two groups.
Grytsenko, Konstantin; Lozovski, Valeri; Strilchuk, Galyna; Schrader, Sigurd
2012-11-07
Nanocomposite films consisting of gold inclusions in the polytetrafluoroethylene (PTFE) matrix were obtained by thermal vacuum deposition. Annealing of the obtained films with different temperatures was used to measure varying of film morphologies. The dependence of optical properties of the films on their morphology was studied. It was established that absorption and profile of the nanocomposite film obtained by thermal vacuum deposition can be changed with annealing owing to the fact that different annealing temperatures lead to different average particle sizes. A method to calculate the optical properties of nanocomposite thin films with inclusions of different sizes was proposed. Thus, comparison of experimental optical spectra with the spectra obtained during the simulation enables estimating average sizes of inclusions. The calculations give the possibility of understanding morphological changes in the structures.
Neodymium isotopic variations in Northwest Pacific waters
NASA Astrophysics Data System (ADS)
Amakawa, Hiroshi; Nozaki, Yoshiyuki; Alibo, Dia Sotto; Zhang, Jing; Fukugawa, Kiyotaka; Nagai, Hisao
2004-02-01
Four vertical profiles of the concentration and isotopic composition of Nd in seawater were obtained in the western North Pacific. Two profiles from the Kuroshio Current regime showed congruently that although the Nd concentration increases gradually with depth, its isotopic composition varies significantly with depth depending upon the water mass occupying the water column. The high-salinity Kuroshio waters originating from the North Pacific Tropical Water (NPTW) carry the least radiogenic Nd (ɛ Nd = -7.4 to -8.7) to this region at ˜250 m from the western margin continental shelves, most likely from the East China Sea. The Nd isotopic compositions in the North Pacific Intermediate Water (NPIW) that occurs at 600 to 1000 m in the subtropical region are fairly uniform at ɛ Nd = -3.7. The profile data from the ˜38° to 40°N Kuroshio/Oyashio mixed water region off Sanriku of Honshu, Japan, also suggest that the newest NPIW with ɛ Nd = -3.2 is formed there by the mixing of various source waters, and the radiogenic component of Nd is derived mainly from the Oyashio waters. In the Pacific Deep Water (PDW) below ˜1000 m, the Nd isotopic composition is neither vertically nor horizontally homogeneous, suggesting that it serves as a useful tracer for sluggish deep water circulation as well. Two profiles from the Izu-Ogasawara Trench showed a minimum ɛ Nd value at ˜2000 m, suggesting that there exists a horizontal advective flow in the vicinity of Honshu, Japan. There is some evidence from other chemical properties to support this observation. The waters below 4000 m including those within the trench in the subtropical region have ɛ Nd values of around -5, suggesting that the deep waters are fed from the south along the western boundary, ultimately from the Antarctic Bottom Water (AABW) in the South Pacific. This extends up to ˜40°N along the Japanese Islands. In the subarctic region (>˜42°N), the waters have more radiogenic Nd with ɛ Nd > -4.0 throughout the water column, presumably due to the supply of Nd by weathering in such igneous provinces as the Kuril-Kamchatska-Aleutian Island chain. The lateral inhomogeneity of the Nd isotopic composition in PDW suggests that there may be different circulation and mixing regimes in the North Pacific Basin.
Molecular analyses of two bacterial sampling methods in ligature-induced periodontitis in rats.
Fontana, Carla Raquel; Grecco, Clovis; Bagnato, Vanderlei Salvador; de Freitas, Laura Marise; Boussios, Constantinos I; Soukos, Nikolaos S
2018-02-01
The prevalence profile of periodontal pathogens in dental plaque can vary as a function of the detection method; however, the sampling technique may also play a role in determining dental plaque microbial profiles. We sought to determine the bacterial composition comparing two sampling methods, one well stablished and a new one proposed here. In this study, a ligature-induced periodontitis model was used in 30 rats. Twenty-seven days later, ligatures were removed and microbiological samples were obtained directly from the ligatures as well as from the periodontal pockets using absorbent paper points. Microbial analysis was performed using DNA probes to a panel of 40 periodontal species in the checkerboard assay. The bacterial composition patterns were similar for both sampling methods. However, detection levels for all species were markedly higher for ligatures compared with paper points. Ligature samples provided more bacterial counts than paper points, suggesting that the technique for induction of periodontitis could also be applied for sampling in rats. Our findings may be helpful in designing studies of induced periodontal disease-associated microbiota.
Grezzi, G.; Ayuso, R.A.; de Vivo, B.; Lima, A.; Albanese, S.
2011-01-01
The isotopic signature of geogenic and anthropogenic materials, in combination with concentration data for pollutants, can help trace the origin and the extent of contamination in the environment. This approach is particularly effective if naturally occurring and anthropogenically introduced metals have different isotopic ratios. Lead isotope analysis on soils from 7 profiles (1. m depth) and on groundwaters from 8 wells have been used to determine the impact of human activities on the surface environment of Domizio-Flegreo Littoral. Result obtained show that in sub-rural areas the isotopic composition of the samples collected along the soil profiles of Domizio-Flegreo Littoral is likely mostly controlled by the nature of the parent geologic material (natural) while in more urbanized areas (Giugliano) Pb isotopic composition in superficial soils is mostly influenced by anthropic sources such as motor vehicles. Lead isotopic ratios in groundwaters also show that the use of pesticides and, probably, the influence of aerosols and the presence of illegal waste disposal can influence water quality. ?? 2010 Elsevier B.V.
NASA Astrophysics Data System (ADS)
Röder, F.; Heintze, C.; Pecko, S.; Akhmadaliev, S.; Bergner, F.; Ulbricht, A.; Altstadt, E.
2018-04-01
Ion-irradiation-induced hardening is investigated on six selected reactor pressure vessel (RPV) steels. The steels were irradiated with 5 MeV Fe2+ ions at fluences ranging from 0.01 to 1.0 displacements per atom (dpa) and the induced hardening of the surface layer was probed with nanoindentation. To separate the indentation size effect and the substrate effect from the irradiation-induced hardness profile, we developed an analytic model with the plastic zone of the indentation approximated as a half sphere. This model allows the actual hardness profile to be retrieved and the measured hardness increase to be assigned to the respective fluence. The obtained values of hardness increase vs. fluence are compared for selected pairs of samples in order to extract effects of the RPV steel composition. We identify hardening effects due to increased levels of copper, manganese-nickel and phosphorous. Further comparison with available neutron-irradiated conditions of the same heats of RPV steels indicates pronounced differences of the considered effects of composition for irradiation with neutrons vs. ions.
Vasyurenko, Z P; Opanasenko, L S; Koval', G M; Turyanitsa, A I; Ruban, N M
2001-01-01
The cellular and lipopolysaccharide (LPS) fatty acid compositions of the type strains of Klebsiella pneumoniae, K. oxytoca, K. terrigena, K. planticola, and "K. trevisanii" were studied. The cellular fatty acids of klebsiellae were presented by straight-chain saturated and monounsaturated, cyclopropane, and hydroxy fatty acids. Hexadecanoic, methylenehexadecanoic, octadecenoic and hexadecenoic acids prevailed. The K. pneumoniae strain mainly differed from the strains of other species by two and more times lower level of dodecanoic acid in cells. Variations of cyclopropane and unsaturated fatty acid contents in cells were observed. LPS fatty acids profiles of klebsiellae mainly consisted of straight-chain saturated and hydroxy fatty acids with predominance of tetradecanoic and 3-hydroxytetradecanoic acids. LPS fatty acids profiles of K. oxytoca, K. terrigena, K. planticola, and "K. trevisanii" strains were very similar and differed from that of the K. pneumoniae strain by higher levels of dodecanoic acid (approximately 5-6 times) and absence of 2-hydroxytetradecanoic acid. The obtained data indicated more close relatedness of K. oxytoca, K. terrigena, and K. planticola and some their remoteness from K. pneumoniae.
Okińczyc, Piotr; Szumny, Antoni; Szperlik, Jakub; Kulma, Anna; Franiczek, Roman; Żbikowska, Beata; Krzyżanowska, Barbara; Sroka, Zbigniew
2018-05-25
In this work, we studied similarities and differences between 70% ethanol in water extract (70EE) and essential oils (EOs) obtained from propolis, black poplars ( Populus nigra L.) and aspens ( P. tremula L.) to ascertain which of these is a better indicator of the plant species used by bees to collect propolis precursors. Composition of 70EE was analyzed by UPLC-PDA-MS, while GC-MS was used to research the EOs. Principal component analyses (PCA) and calculations of Spearman's coefficient rank were used for statistical analysis. Statistical analysis exhibited correlation between chemical compositions of propolis and Populus buds' 70EE. In the case of EOs, results were less clear. Compositions of black poplars, aspens EOs and propolises have shown more variability than 70EE. Different factors such as higher instability of EOs compared to 70EE, different degradation pattern of benzyl esters to benzoic acid, differences in plant metabolism and bees' preferences may be responsible for these phenomena. Our research has therefore shown that 70EE of propolis reflected the composition of P. nigra or complex aspen⁻black poplar origin.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campos-Martin, J.M.; Fierro, J.L.G.; Guerrero-Ruiz, A.
1995-10-01
A series of copper-zinc-chromium catalysts of different compositions and calcination temperatures has been prepared, characterized by several techniques (BET specific surface area, XRD, gravimetric TPR, TPD-CO, and XPS), and tested under high alcohol synthesis (HAS) conditions. CO hydrogenation was carried out at reaction temperatures of 523-598 K and 50 bar total pressure. The influence of catalyst composition, calcination temperature, and surface characteristics on the HAS selectivity was studied. The optimum HAS yields were found in the low Cr content region, but chromium was needed. Although chromium oxide does not seem to be involved in the catalytic site, its presence inmore » the catalyst composition is essential, owing to the larger specific surfaces and catalyst stability obtained at the highest reaction temperatures. For low Cr content composition, the temperature-programmed reduction (TPR) profiles were shifted to higher temperatures and simultaneously larger CO{sub 2} amounts were found in the temperature-programmed desorption profiles of adsorbed CO (TPD-CO). Photoelectron spectra (XPS) revealed that the oxidation state of copper is Cu{sup 2+} in the calcined catalysts and Cu{sup O} in the reduced ones; Cu{sup +} was only stabilized in a CuCr{sub 2}O{sub 4} spinel in the Cr-rich catalysts. These features derived from catalyst characterization are discussed in the framework of the catalytic behaviour for HAS synthesis. 53 refs., 7 figs., 4 tabs.« less
NASA Astrophysics Data System (ADS)
Sauzède, R.; Lavigne, H.; Claustre, H.; Uitz, J.; Schmechtig, C.; D'Ortenzio, F.; Guinet, C.; Pesant, S.
2015-04-01
In vivo chlorophyll a fluorescence is a proxy of chlorophyll a concentration, and is one of the most frequently measured biogeochemical properties in the ocean. Thousands of profiles are available from historical databases and the integration of fluorescence sensors to autonomous platforms led to a significant increase of chlorophyll fluorescence profile acquisition. To our knowledge, this important source of environmental data has not yet been included in global analyses. A total of 268 127 chlorophyll fluorescence profiles from several databases as well as published and unpublished individual sources were compiled. Following a robust quality control procedure detailed in the present paper, about 49 000 chlorophyll fluorescence profiles were converted in phytoplankton biomass (i.e. chlorophyll a concentration) and size-based community composition (i.e. microphytoplankton, nanophytoplankton and picophytoplankton), using a~method specifically developed to harmonize fluorescence profiles from diverse sources. The data span over five decades from 1958 to 2015, including observations from all major oceanic basins and all seasons, and depths ranging from surface to a median maximum sampling depth of around 700 m. Global maps of chlorophyll a concentration and phytoplankton community composition are presented here for the first time. Monthly climatologies were computed for three of Longhurst's ecological provinces in order to exemplify the potential use of the data product. Original data sets (raw fluorescence profiles) as well as calibrated profiles of phytoplankton biomass and community composition are available in open access at PANGAEA, Data Publisher for Earth and Environmental Science. Raw fluorescence profiles: http://doi.pangaea.de/10.1594/PANGAEA.844212 and Phytoplankton biomass and community composition: http://doi.pangaea.de/10.1594/PANGAEA.844485.
Tsasi, Gerasimia; Mailis, Theofilos; Daskalaki, Artemis; Sakadani, Eleni; Razis, Panagis; Samaras, Yiannis; Skaltsa, Helen
2017-01-01
Five varieties of Ocimum basilicum L. namely lettuce, cinnamon, minimum, latifolia, and violetto were separately cultivated in field and greenhouse in the island Kefalonia (Greece). The effect of successive harvesting to the essential oil content was evaluated. In total 23 samples of essential oils (EOs) were analyzed by GC-FID and GC-MS. Ninety-six constituents, which accounted for almost 99% of the oils, were identified. Cluster analysis was performed for all of the varieties in greenhouse and field conditions, in order to investigate the possible differentiation on the chemical composition of the essential oils, obtained between harvests during growing period. Each basil variety showed a unique chemical profile, but also the essential oil composition within each variety seems to be differentiated, affected by the harvests and the cultivation site. PMID:28927018
Khatib, Mohamad; Giuliani, Camilla; Rossi, Federico; Adessi, Alessandra; Al-Tamimi, Amal; Mazzola, Giuseppe; Di Gioia, Diana; Innocenti, Marzia; Mulinacci, Nadia
2017-11-15
The main crude polysaccharides (CPS), extracted from two widely cultivated pomegranate varieties, Laffan and Wonderful, were studied and characterized. We obtained the highest CPS extraction yield (approximatively 10% w/w on dried matter) by 1h of decoction (ratio 1/40w/v). The predominant polymers (75-80%) of the CPS samples showed a hydrodynamic volume close to 2000kDa by size exclusion chromatography and the exocarp and mesocarp profiles were very similar. The proton spectra ( 1 H NMR), according to sugar composition and gelling ability, confirmed the main polysaccharide fractions were pectin with different acylation and methylation degree. The CPS from Laffan and Wonderful mesocarp showed prebiotic properties in vitro with Lactobacillus and Bifidobacterium strains. The composition of the decoction (12% ellagitannins and 10% of CPS) obtained by a green extraction process of pomegranate by-products, makes it a suitable component of functional food formulations. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Abbas, Zaheer; Hasnain, Jafar
A numerical study is performed to examine the two-phase magnetoconvection and heat transfer phenomena of Fe3O4 -kerosene nanofluid flow in a horizontal composite porous annulus with an external magnetic field. The annulus is filled with immiscible fluids flowing between two concentric cylinders. The governing equations of the flow problem are obtained using Darcy-Brinkman model. Heat transfer is analyzed in the presence of viscous and Darcian dissipation terms. The shooting method is used as a tool to solve the obtained non-linear ordinary differential equations for the velocity and temperature profiles. The velocity and temperature distributions are analyzed and discussed under the influence of involved flow parameters with the aid of graphs. It is found that both velocity and temperature of fluid are decreased with ferroparticle volume fraction. In addition to that, it is also presented that the existence of magnetic field decreases the benefit of ferrofluids in heat transfer progression.
Performance of SMA-reinforced composites in an aerodynamic profile
NASA Astrophysics Data System (ADS)
Simpson, John; Boller, Christian
2002-07-01
Within the European collaborative applied fundamental research project ADAPT, fundamentals of SMA-reinforced composites were evaluated and the specific manufacturing techniques for these composites developed and realised. The involved partners are listed at the end. To demonstrate applicability of these composites a realistically scaled aerodynamic profile of around 0.5m span by 0.5m root chord was designed, manufactured and assembled. The curved skins were manufactured as SMA composites with two layers of SMA-wires integrated into the layup of aramid fibre prepregs. All SMA wires were connected such that they can be operated as individual sets of wires and at low voltages, similar to the conditions for electrical energy generation in a real aircraft. The profile was then mounted on a vibration test rig and activated and excited by a shaker at its tip which allowed to test the dynamic performance of the profile under different external loading conditions with various internal actuation conditions through the SMA wires. The paper includes some background of the design and manufacturing of the aerodynamic profile and will discuss some of the results determined recently on the test rig. A view with regard to future wind tunnel testing will be given as well.
Study of neutral composition of lower thermosphere at Fort Churchill.
NASA Technical Reports Server (NTRS)
Nier, A. O.; Hickman, D. R.
1973-01-01
On Feb. 4 and 6, 1969, and May 11, 1970, Aerobee rockets carrying neutral mass spectrometers were flown at Fort Churchill, Canada during conditions of low geomagnetic activity. As in earlier flights at White Sands, New Mexico, each rocket carried both 'open' and 'closed' ion source instruments. Vertical profiles of N2, O2, O, Ar, and He were measured. Results obtained were essentially the same as those observed at White Sands except that for the winter flights helium appeared to be in diffusive equilibrium.
Morton, J.L.; Holmes, M.L.; Koski, R.A.
1987-01-01
Seismic-reflection profiles over the sediment-filled Escanaba Trough at the southern Gorda Ridge reveal a series of volcanic centers that pierce the sediment. The volcanic edifices are 3 to 6 km in diameter and are spaced at 15 to 20 km intervals along the axis of the trough. Composition and form of sulfide samples obtained from the bank suggest significant interaction between hydrothermal fluids and sediment at depth, and deposition of sulfide within the sediment pile.-from Authors
Kozlovsky, A G; Zhelifonova, V P; Antipova, T V; Baskunov, B P; Ivanushkina, N E; Ozerskaya, S M
2014-01-01
Data were obtained on the species composition of mycelial fungi isolated from the air of workrooms and production premises in cheese-making and meat-processing plants. The strains studied were shown to be capable of producing various low molecular weight compounds. Many of them are mycotoxins such as α-cyclopiazonic acid (CPA), mycophenolic acid (MPA), citrinin, cladosporin, roquefortine and ergot alkaloids. The profiles of the secondary metabolites were used to elucidate the species' names of the isolated strains.
NASA Technical Reports Server (NTRS)
Evans, J. S.; Schexnayder, C. J., Jr.
1979-01-01
Good agreement has been obtained between published profiles of composition and pitot pressure and the calculated results from a computer program in which finite rate chemistry was used. Significant differences are noted between results calculated using 7 species and 8 reactions and those calculated using 12 species and 25 reactions. Differences are also found between results in which the effect of unmixedness on reaction in turbulent flow is applied or is not applied.
NASA Astrophysics Data System (ADS)
Endrino, J. L.; Sánchez-López, J. C.; Escobar Galindo, R.; Horwat, D.; Anders, A.
2010-11-01
Silver-containing diamond-like-carbon (DLC) is a promising material for biomedical implants due to its excellent combination of antibacterial and mechanical properties. In this work, a dual-cathode pulsed filtered cathodic arc source containing silver and graphite rods was employed in order to obtain DLC samples with various silver contents. Chemical composition of the samples was analyzed by acquiring their compositional depth-profiles using radio-frequency Glow Discharge Optical Emission Spectroscopy (rf-GDOES), while the microstructural properties were analyzed by X-ray diffraction and Raman spectroscopy. Tribological studies carried out against UHMWPE balls in fetal bovine serum indicate that the presence of silver in DLC could be beneficial to reduce the wear of the polymeric surfaces.
Rhizosphere Protists Change Metabolite Profiles in Zea mays.
Kuppardt, Anke; Fester, Thomas; Härtig, Claus; Chatzinotas, Antonis
2018-01-01
Plant growth and productivity depend on the interactions of the plant with the associated rhizosphere microbes. Rhizosphere protists play a significant role in this respect: considerable efforts have been made in the past to reveal the impact of protist-bacteria interactions on the remobilization of essential nutrients for plant uptake, or the grazing induced changes on plant-growth promoting bacteria and the root-architecture. However, the metabolic responses of plants to the presence of protists or to protist-bacteria interactions in the rhizosphere have not yet been analyzed. Here we studied in controlled laboratory experiments the impact of bacterivorous protists in the rhizosphere on maize plant growth parameters and the bacterial community composition. Beyond that we investigated the induction of plant biochemical responses by separately analyzing above- and below-ground metabolite profiles of maize plants incubated either with a soil bacterial inoculum or with a mixture of soil bacteria and bacterivorous protists. Significantly distinct leaf and root metabolite profiles were obtained from plants which grew in the presence of protists. These profiles showed decreased levels of a considerable number of metabolites typical for the plant stress reaction, such as polyols, a number of carbohydrates and metabolites connected to phenolic metabolism. We assume that this decrease in plant stress is connected to the grazing induced shifts in rhizosphere bacterial communities as shown by distinct T-RFLP community profiles. Protist grazing had a clear effect on the overall bacterial community composition, richness and evenness in our microcosms. Given the competition of plant resource allocation to either defense or growth, we propose that a reduction in plant stress levels caused directly or indirectly by protists may be an additional reason for corresponding positive effects on plant growth.
Rhizosphere Protists Change Metabolite Profiles in Zea mays
Kuppardt, Anke; Fester, Thomas; Härtig, Claus; Chatzinotas, Antonis
2018-01-01
Plant growth and productivity depend on the interactions of the plant with the associated rhizosphere microbes. Rhizosphere protists play a significant role in this respect: considerable efforts have been made in the past to reveal the impact of protist-bacteria interactions on the remobilization of essential nutrients for plant uptake, or the grazing induced changes on plant-growth promoting bacteria and the root-architecture. However, the metabolic responses of plants to the presence of protists or to protist-bacteria interactions in the rhizosphere have not yet been analyzed. Here we studied in controlled laboratory experiments the impact of bacterivorous protists in the rhizosphere on maize plant growth parameters and the bacterial community composition. Beyond that we investigated the induction of plant biochemical responses by separately analyzing above- and below-ground metabolite profiles of maize plants incubated either with a soil bacterial inoculum or with a mixture of soil bacteria and bacterivorous protists. Significantly distinct leaf and root metabolite profiles were obtained from plants which grew in the presence of protists. These profiles showed decreased levels of a considerable number of metabolites typical for the plant stress reaction, such as polyols, a number of carbohydrates and metabolites connected to phenolic metabolism. We assume that this decrease in plant stress is connected to the grazing induced shifts in rhizosphere bacterial communities as shown by distinct T-RFLP community profiles. Protist grazing had a clear effect on the overall bacterial community composition, richness and evenness in our microcosms. Given the competition of plant resource allocation to either defense or growth, we propose that a reduction in plant stress levels caused directly or indirectly by protists may be an additional reason for corresponding positive effects on plant growth. PMID:29780370
Li, Tongtong; Long, Meng; Li, Huan; Gatesoupe, François-Joël; Zhang, Xujie; Zhang, Qianqian; Feng, Dongyue; Li, Aihua
2017-01-01
Gut microbiota play key roles in host nutrition and metabolism. However, little is known about the relationship between host genetics, gut microbiota and metabolic profiles. Here, we used high-throughput sequencing and gas chromatography/mass spectrometry approaches to characterize the microbiota composition and the metabolite profiles in the gut of five cyprinid fish species with three different feeding habits raised under identical husbandry conditions. Our results showed that host species and feeding habits significantly affect not only gut microbiota composition but also metabolite profiles (ANOSIM, p ≤ 0.05). Mantel test demonstrated that host phylogeny, gut microbiota, and metabolite profiles were significantly related to each other (p ≤ 0.05). Additionally, the carps with the same feeding habits had more similarity in gut microbiota composition and metabolite profiles. Various metabolites were correlated positively with bacterial taxa involved in food degradation. Our results shed new light on the microbiome and metabolite profiles in the gut content of cyprinid fishes, and highlighted the correlations between host genotype, fish gut microbiome and putative functions, and gut metabolite profiles. PMID:28367147
3-D Surface Depression Profiling Using High Frequency Focused Air-Coupled Ultrasonic Pulses
NASA Technical Reports Server (NTRS)
Roth, Don J.; Kautz, Harold E.; Abel, Phillip B.; Whalen, Mike F.; Hendricks, J. Lynne; Bodis, James R.
1999-01-01
Surface topography is an important variable in the performance of many industrial components and is normally measured with diamond-tip profilometry over a small area or using optical scattering methods for larger area measurement. This article shows quantitative surface topography profiles as obtained using only high-frequency focused air-coupled ultrasonic pulses. The profiles were obtained using a profiling system developed by NASA Glenn Research Center and Sonix, Inc (via a formal cooperative agreement). (The air transducers are available as off-the-shelf items from several companies.) The method is simple and reproducible because it relies mainly on knowledge and constancy of the sound velocity through the air. The air transducer is scanned across the surface and sends pulses to the sample surface where they are reflected back from the surface along the same path as the incident wave. Time-of-flight images of the sample surface are acquired and converted to depth/surface profile images using the simple relation (d = V*t/2) between distance (d), time-of-flight (t), and the velocity of sound in air (V). The system has the ability to resolve surface depression variations as small as 25 microns, is useable over a 1.4 mm vertical depth range, and can profile large areas only limited by the scan limits of the particular ultrasonic system. (Best-case depth resolution is 0.25 microns which may be achievable with improved isolation from vibration and air currents.) The method using an optimized configuration is reasonably rapid and has all quantitative analysis facilities on-line including 2-D and 3-D visualization capability, extreme value filtering (for faulty data), and leveling capability. Air-coupled surface profilometry is applicable to plate-like and curved samples. In this article, results are shown for several proof-of-concept samples, plastic samples burned in microgravity on the STS-54 space shuttle mission, and a partially-coated cylindrical ceramic composite sample. Impressive results were obtained for all samples when compared with diamond-tip profiles and measurements from micrometers. The method is completely nondestructive, noninvasive, non-contact and does not require light-reflective surfaces.
Is language impairment more common than executive dysfunction in amyotrophic lateral sclerosis?
Taylor, Lorna J; Brown, Richard G; Tsermentseli, Stella; Al-Chalabi, Ammar; Shaw, Christopher E; Ellis, Catherine M; Leigh, P Nigel; Goldstein, Laura H
2013-05-01
Systematic explorations of language abilities in patients with amyotrophic lateral sclerosis (ALS) are lacking in the context of wider cognitive change. Neuropsychological assessment data were obtained from 51 patients with ALS and 35 healthy controls matched for age, gender and IQ. Composite scores were derived for the domains of language and executive functioning. Domain impairment was defined as a composite score ≤5th centile relative to the control mean. Cognitive impairment was also classified using recently published consensus criteria. The patients with ALS were impaired on language and executive composite scores. Language domain impairment was found in 43% of patients with ALS, and executive domain impairment in 31%. Standardised language and executive composite scores correlated in the ALS group (r=0.68, p<0.001). Multiple regression analyses indicated that scores on the executive composite accounted for 44% of the variance in language composite scores. Language impairments are at least as prevalent as executive dysfunction in ALS. While the two domains are strongly associated, executive dysfunction does not fully account for the profile of language impairments observed, further highlighting the heterogeneity of cognitive impairment in non-demented patients with ALS.
Bergamaschi, Matteo; Bittante, Giovanni
2017-08-01
In this research two-dimensional GC was used to analyse, for the first time, the detailed fatty acid (FA) profiles of 11 dairy matrices: raw milk (evening whole, evening partially skimmed, morning whole, and vat milk), cream, fresh cheese, whey, ricotta, scotta, 6- and 12-month-ripened cheeses, obtained across artisanal cheese- and ricotta-making trials carried out during the summer period while cows were on highland pastures. Samples were collected during 7 cheese- and ricotta-making procedures carried out at 2-week intervals from bulk milk to study possible differences in the transfer and modification of FA. Compared with morning milk, evening milk had fewer de novo synthetised FA. The detailed FA profile of partially skimmed milk differed little from that of evening whole milk before skimming, but the cream obtained differed from partially skimmed milk and from fresh cheese in about half the FA, due mainly to higher contents of all de novo FA, and lower contents of n-3 and n-6 FA. Fresh cheese and whey had similar FA profiles. The ricotta manufacturing process affected the partition of FA between ricotta and scotta, the FA profile of the latter differing in terms of groups and individual FA from the former, whereas ricotta and fresh cheese had similar composition of FA. In general, there was an increase in medium-chain saturated FA, and a decrease in many polyunsaturated FA during the first 6 months of ripening, but not during the second 6 months. Two-dimensional GC yielded a very detailed and informative FA profile on all the 11 dairy products and by-products analysed.
NASA Technical Reports Server (NTRS)
Mirdamadi, M.; Johnson, W. S.
1994-01-01
Titanium matrix composites (TMC) are being evaluated as structural materials for elevated temperature applications in future generation hypersonic vehicles. In such applications, TMC components are subjected to complex thermomechanical loading profiles at various elevated temperatures. Therefore, thermomechanical fatigue (TMF) testing, using a simulated mission profile, is essential for evaluation and development of life prediction methodologies. The objective of the research presented in this paper was to evaluate the TMF response of the (0/90)2s SCS-6/Timetal-21S subjected to a generic hypersonic flight profile and its portions with a temperature ranging from -130 C to 816 C. It was found that the composite modulus, prior to rapid degradation, had consistent values for all the profiles tested. A micromechanics based analysis was used to predict the stress-strain response of the laminate and of the constituents in each ply during thermomechanical loading conditions by using only constituent properties as input. The fiber was modeled as elastic with transverse orthotropic and temperature dependent properties. The matrix was modeled using a thermoviscoplastic constitutive relation. In the analysis, the composite modulus degradation was assumed to result from matrix cracking and was modeled by reducing the matrix modulus. Fatigue lives of the composite subjected to the complex generic hypersonic flight profile were well correlated using the predicted stress in 0 degree fibers.
Metabolomic profiles as reliable biomarkers of dietary composition123
Esko, Tõnu; Hirschhorn, Joel N; Feldman, Henry A; Hsu, Yu-Han H; Deik, Amy A; Clish, Clary B; Ebbeling, Cara B; Ludwig, David S
2017-01-01
Background: Clinical nutrition research often lacks robust markers of compliance, complicating the interpretation of clinical trials and observational studies of free-living subjects. Objective: We aimed to examine metabolomics profiles in response to 3 diets that differed widely in macronutrient composition during a controlled feeding protocol. Design: Twenty-one adults with a high body mass index (in kg/m2; mean ± SD: 34.4 ± 4.9) were given hypocaloric diets to promote weight loss corresponding to 10–15% of initial body weight. They were then studied during weight stability while consuming 3 test diets, each for a 4-wk period according to a crossover design: low fat (60% carbohydrate, 20% fat, 20% protein), low glycemic index (40% carbohydrate, 40% fat, 20% protein), or very-low carbohydrate (10% carbohydrate, 60% fat, 30% protein). Plasma samples were obtained at baseline and at the end of each 4-wk period in the fasting state for metabolomics analysis by using liquid chromatography–tandem mass spectrometry. Statistical analyses included adjustment for multiple comparisons. Results: Of 333 metabolites, we identified 152 whose concentrations differed for ≥1 diet compared with the others, including diacylglycerols and triacylglycerols, branched-chain amino acids, and markers reflecting metabolic status. Analysis of groups of related metabolites, with the use of either principal components or pathways, revealed coordinated metabolic changes affected by dietary composition, including pathways related to amino acid metabolism. We constructed a classifier using the metabolites that differed between diets and were able to correctly identify the test diet from metabolite profiles in 60 of 63 cases (>95% accuracy). Analyses also suggest differential effects by diet on numerous cardiometabolic disease risk factors. Conclusions: Metabolomic profiling may be used to assess compliance during clinical nutrition trials and the validity of dietary assessment in observational studies. In addition, this methodology may help elucidate mechanistic pathways linking diet to chronic disease risk. This trial was registered at clinicaltrials.gov as NCT00315354. PMID:28077380
Metabolomic profiles as reliable biomarkers of dietary composition.
Esko, Tõnu; Hirschhorn, Joel N; Feldman, Henry A; Hsu, Yu-Han H; Deik, Amy A; Clish, Clary B; Ebbeling, Cara B; Ludwig, David S
2017-03-01
Background: Clinical nutrition research often lacks robust markers of compliance, complicating the interpretation of clinical trials and observational studies of free-living subjects. Objective: We aimed to examine metabolomics profiles in response to 3 diets that differed widely in macronutrient composition during a controlled feeding protocol. Design: Twenty-one adults with a high body mass index (in kg/m 2 ; mean ± SD: 34.4 ± 4.9) were given hypocaloric diets to promote weight loss corresponding to 10-15% of initial body weight. They were then studied during weight stability while consuming 3 test diets, each for a 4-wk period according to a crossover design: low fat (60% carbohydrate, 20% fat, 20% protein), low glycemic index (40% carbohydrate, 40% fat, 20% protein), or very-low carbohydrate (10% carbohydrate, 60% fat, 30% protein). Plasma samples were obtained at baseline and at the end of each 4-wk period in the fasting state for metabolomics analysis by using liquid chromatography-tandem mass spectrometry. Statistical analyses included adjustment for multiple comparisons. Results: Of 333 metabolites, we identified 152 whose concentrations differed for ≥1 diet compared with the others, including diacylglycerols and triacylglycerols, branched-chain amino acids, and markers reflecting metabolic status. Analysis of groups of related metabolites, with the use of either principal components or pathways, revealed coordinated metabolic changes affected by dietary composition, including pathways related to amino acid metabolism. We constructed a classifier using the metabolites that differed between diets and were able to correctly identify the test diet from metabolite profiles in 60 of 63 cases (>95% accuracy). Analyses also suggest differential effects by diet on numerous cardiometabolic disease risk factors. Conclusions: Metabolomic profiling may be used to assess compliance during clinical nutrition trials and the validity of dietary assessment in observational studies. In addition, this methodology may help elucidate mechanistic pathways linking diet to chronic disease risk. This trial was registered at clinicaltrials.gov as NCT00315354. © 2017 American Society for Nutrition.
Zou, Lingyun; Wang, Zhengzhi; Huang, Jiaomin
2007-12-01
Subcellular location is one of the key biological characteristics of proteins. Position-specific profiles (PSP) have been introduced as important characteristics of proteins in this article. In this study, to obtain position-specific profiles, the Position Specific Iterative-Basic Local Alignment Search Tool (PSI-BLAST) has been used to search for protein sequences in a database. Position-specific scoring matrices are extracted from the profiles as one class of characteristics. Four-part amino acid compositions and 1st-7th order dipeptide compositions have also been calculated as the other two classes of characteristics. Therefore, twelve characteristic vectors are extracted from each of the protein sequences. Next, the characteristic vectors are weighed by a simple weighing function and inputted into a BP neural network predictor named PSP-Weighted Neural Network (PSP-WNN). The Levenberg-Marquardt algorithm is employed to adjust the weight matrices and thresholds during the network training instead of the error back propagation algorithm. With a jackknife test on the RH2427 dataset, PSP-WNN has achieved a higher overall prediction accuracy of 88.4% rather than the prediction results by the general BP neural network, Markov model, and fuzzy k-nearest neighbors algorithm on this dataset. In addition, the prediction performance of PSP-WNN has been evaluated with a five-fold cross validation test on the PK7579 dataset and the prediction results have been consistently better than those of the previous method on the basis of several support vector machines, using compositions of both amino acids and amino acid pairs. These results indicate that PSP-WNN is a powerful tool for subcellular localization prediction. At the end of the article, influences on prediction accuracy using different weighting proportions among three characteristic vector categories have been discussed. An appropriate proportion is considered by increasing the prediction accuracy.
Laboratory-based electrical conductivity at Martian mantle conditions
NASA Astrophysics Data System (ADS)
Verhoeven, Olivier; Vacher, Pierre
2016-12-01
Information on temperature and composition of planetary mantles can be obtained from electrical conductivity profiles derived from induced magnetic field analysis. This requires a modeling of the conductivity for each mineral phase at conditions relevant to planetary interiors. Interpretation of iron-rich Martian mantle conductivity profile therefore requires a careful modeling of the conductivity of iron-bearing minerals. In this paper, we show that conduction mechanism called small polaron is the dominant conduction mechanism at temperature, water and iron content conditions relevant to Mars mantle. We then review the different measurements performed on mineral phases with various iron content. We show that, for all measurements of mineral conductivity reported so far, the effect of iron content on the activation energy governing the exponential decrease in the Arrhenius law can be modeled as the cubic square root of the iron content. We recast all laboratory results on a common generalized Arrhenius law for iron-bearing minerals, anchored on Earth's mantle values. We then use this modeling to compute a new synthetic profile of Martian mantle electrical conductivity. This new profile matches perfectly, in the depth range [100,1000] km, the electrical conductivity profile recently derived from the study of Mars Global Surveyor magnetic field measurements.
Evolution of Elemental Composition and Morphology in Fusion Reactor's First Wall
NASA Astrophysics Data System (ADS)
Kim, Yong W.
2007-11-01
Forcing of a multi-element alloy by a gradient field can modify the spatial profile of its elemental composition. The gradient field may be in the imposed temperature or the flux of impinging particles. In a fusion device, both scenarios apply. The consequences must be well understood because they change the thermal transport properties as well as the strength, corrosion and wear characteristics of the first wall materials. Given the large number of directions material evolution can take, new robust methods of near-surface composition analyses are needed. This paper presents a new measurement methodology and requisite instrumentation, which can provide measures of local elemental composition and transport properties simultaneously by time-resolved spectroscopy of laser-produced plasma (LPP) plume emissions from the specimen surfaces. The studies to date show that the composition profiles can be modified thermally in a reproducible manner; disparate thermal transport of constituent atoms can incur modifications of near-surface composition profiles.[Y.W. Kim, Int. J. Thermophysics 28, 732 (2007)] Also, disparate fluxes of fuel particles, fusion products and impurities force the first walls in myriad ways. Repetitive application of the LPP analysis can resolve the near-surface composition profile as well as transport properties over several microns with depth resolutions to 20 nm. Work supported in part by NSF-DMR.
NASA Technical Reports Server (NTRS)
Kuzmanoski, Maja; Box, M. A.; Schmid, B.; Box, G. P.; Wang, J.; Russell, P. B.; Bates, D.; Jonsson, H. H.; Welton, Ellsworth J.; Flagan, R. C.
2005-01-01
For a vertical profile with three distinct layers (marine boundary, pollution and dust), observed during the ACE-Asia campaign, we carried out a comparison between the modeled lidar ratio vertical profile and that obtained from collocated airborne NASA AATS-14 sunphotometer and shipborne Micro-Pulse Lidar (MPL) measurements. Vertically resolved lidar ratio was calculated from two size distribution vertical profiles - one obtained by inversion of sunphotometer-derived extinction spectra, and one measured in-situ - combined with the same refractive index model based on aerosol chemical composition. The aerosol model implies single scattering albedos of 0.78 - 0.81 and 0.93 - 0.96 at 0.523 microns (the wavelength of the lidar measurements), in the pollution and dust layers, respectively. The lidar ratios calculated from the two size distribution profiles have close values in the dust layer; they are however, significantly lower than the lidar ratios derived from combined lidar and sunphotometer measurements, most probably due to the use of a simple nonspherical model with a single particle shape in our calculations. In the pollution layer, the two size distribution profiles yield generally different lidar ratios. The retrieved size distributions yield a lidar ratio which is in better agreement with that derived from lidar/sunphotometer measurements in this layer, with still large differences at certain altitudes (the largest relative difference was 46%). We explain these differences by non-uniqueness of the result of the size distribution retrieval and lack of information on vertical variability of particle refractive index. Radiative transfer calculations for this profile showed significant atmospheric radiative forcing, which occurred mainly in the pollution layer. We demonstrate that if the extinction profile is known then information on the vertical structure of absorption and asymmetry parameter is not significant for estimating forcing at TOA and the surface, while it is of importance for estimating vertical profiles of radiative forcing and heating rates.
NASA Astrophysics Data System (ADS)
Quade, M. E.; Brueggemann, N.; Graf, A.; Rothfuss, Y.
2017-12-01
Water stable isotopes are powerful tools for partitioning net into raw water fluxes such as evapotranspiration (ET) into soil evaporation (E) and plant transpiration (T). The isotopic methodology for ET partitioning is based on the fact that E and T have distinct water stable isotopic compositions, which in turn relies on the fact that each flux is differently affected by isotopic kinetic effects. An important work to be performed in parallel to field measurements is to better characterize these kinetic effects in the laboratory under controlled conditions. A soil evaporation laboratory experiment was conducted to retrieve characteristic values of the kinetic fractionation factor (αK) under varying soil and atmospheric water conditions. For this we used a combined soil and atmosphere column to monitor the soil and atmospheric water isotopic composition profiles at a high temporal and vertical resolution in a nondestructive manner by combining micro-porous membranes and laser spectroscopy. αK was calculated by using a well-known isotopic evaporation model in an inverse mode with the isotopic composition of E as one input variable, which was determined using a micro-Keeling regression plot. Knowledge on αK was further used in the field (Selhausen, North Rhine-Westphalia, Germany) to partition ET of catch crops and sugar beet (Beta vulgaris) during one growing season. Soil and atmospheric water isotopic profiles were measured automatically across depths and heights following a similar modus operandi as in the laboratory experiment. Additionally, a newly developed continuously moving elevator was used to obtain water vapor isotopic composition profiles with a high vertical resolution between soil surface, plant canopy and atmosphere. Finally, soil and plant samples were collected destructively to provide a comparison with the traditional isotopic methods. Our results illustrate the changing proportions of T and E along the growing season and demonstrate the applicability of our new non-destructive approach to field conditions.
Kharbach, Mourad; Kamal, Rabie; Mansouri, Mohammed Alaoui; Marmouzi, Ilias; Viaene, Johan; Cherrah, Yahia; Alaoui, Katim; Vercammen, Joeri; Bouklouze, Abdelaziz; Vander Heyden, Yvan
2018-10-15
This study investigated the effectiveness of SIFT-MS versus chemical profiling, both coupled to multivariate data analysis, to classify 95 Extra Virgin Argan Oils (EVAO), originating from five Moroccan Argan forest locations. The full scan option of SIFT-MS, is suitable to indicate the geographic origin of EVAO based on the fingerprints obtained using the three chemical ionization precursors (H 3 O + , NO + and O 2 + ). The chemical profiling (including acidity, peroxide value, spectrophotometric indices, fatty acids, tocopherols- and sterols composition) was also used for classification. Partial least squares discriminant analysis (PLS-DA), soft independent modeling of class analogy (SIMCA), K-nearest neighbors (KNN), and support vector machines (SVM), were compared. The SIFT-MS data were therefore fed to variable-selection methods to find potential biomarkers for classification. The classification models based either on chemical profiling or SIFT-MS data were able to classify the samples with high accuracy. SIFT-MS was found to be advantageous for rapid geographic classification. Copyright © 2018 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Sawaki, Yasuyo
2007-01-01
This is a construct validation study of a second language speaking assessment that reported a language profile based on analytic rating scales and a composite score. The study addressed three key issues: score dependability, convergent/discriminant validity of analytic rating scales and the weighting of analytic ratings in the composite score.…
Comparison of the fatty acid profile of Spanish infant formulas and Galician women breast milk.
Barreiro, Rocío; Regal, Patricia; López-Racamonde, Olga; Cepeda, Alberto; Fente, Cristina A
2018-02-01
The importance of dietary lipids during childhood is evident, as they are necessary for correct growth and development of the newborn. When breastfeeding is not possible, infant formulas are designed to mimic human milk as much as possible to fulfill infant's requirements. However, the composition of these dairy products is relatively constant, while human milk is not a uniform bio-fluid and changes according to the requirements of the baby. In this study, breast milk samples were donated by 24 Spanish mothers in different lactation stages and different infant formulas were purchased in supermarkets and pharmacies. Gas chromatography coupled to flame ionization detection was used for the fatty acid determination. Compared to breast milk, first-stage formulas are apparently very similar in composition; however, no major differences were observed in the fatty acid profiles between formulas of different lactation stages. The Galician women breast milk has a fatty acid profile rich in oleic acid, linoleic acid, arachidonic acid, and docosahexaenoic acid. When comparing human milk with formulas, it becomes evident that the manufacturers tend to enrich the formulas with essential fatty acids (especially with α-linolenic acid), but arachidonic and docosahexaenoic acid levels are lower than in breast milk. Additionally, the obtained results demonstrated that after 1 year of lactation, human milk is still a good source of energy, essential fatty acids, and long-chain polyunsaturated fatty acids for the baby.
Ziani, Borhane E C; Barros, Lillian; Boumehira, Ali Z; Bachari, Khaldoun; Heleno, Sandrina A; Alves, Maria Jose; Ferreira, Isabel C F R
2018-01-24
The infusions of Thymus pallescens Noë, Saccocalyx satureioides Coss. et Dur., Ptychotis verticillata Briq. and Limoniastrum guyonianum Boiss. have been used as medicinal remedies for many diseases in Algerian folk medicine. These species have also been well documented as rich sources of phytochemicals, such as phenolic compounds with wide diversified chemical structures, which exhibit far-ranging biological activities. Thus, the phenolic compound profile of the aqueous extracts, obtained by infusing, of the mentioned species was obtained by HPLC-DAD-ESI/MS, and their antibacterial activity was evaluated against clinical isolates. Several phenolic acids were identified and quantified, particularly caffeic acid derivatives along with glycosylated flavonoids. T. pallescens and S. satureioides contain 13 phenolic compounds, where rosmarinic acid was the most abundant phenolic acid present, while L. guyonianum presented myricetin-3-O-glucoside and myricetin-O-rhamnoside as the main compounds among the eight detected molecules. P. verticillata presented a profile of ten phenolic compounds, where 5-O-caffeoylquinic acid was the most abundant phenolic acid, followed by the flavone luteolin-3-O-glucoside. The antibacterial activity of the infusions ranged between 2.5 and 20 mg mL -1 (MIC values), and L. guyonianum showed the highest activity against all of the tested bacteria, Staphylococcus aureus and Pseudomonas aeruginosa being the most sensitive and resistant strains, respectively. Thus, the studied plant species are sources of natural antibacterial substances that can be used to fight against pathogenic microorganisms.
NASA Astrophysics Data System (ADS)
Angst, Gerrit; John, Stephan; Rethemeyer, Janet; Kögel-Knabner, Ingrid; Mueller, Carsten W.
2014-05-01
Subsoils can significantly contribute to the terrestrial C pool. While processes of C turnover and storage in topsoils are generally well understood, little is known about subsoils. Our project, embedded within the DFG research group FOR 1806, aims to contribute to the knowledge about subsoil C by differentiating soil organic matter (SOM) in terms of its origin and its composition. In order to obtain a meaningful sample set we studied three soil ditches, 3.15 m in length and 2.15 m in depth, in a podzolic Cambisol under European beech (Fagus sylvatica L.) north of Hannover, Germany. In a to date unique sampling approach we took 64 soil samples in a regular vertical grid in each of the soil profiles, thus identifying possible gradients between top- and subsoil. The samples were subjected to a combined density and particle size fractionation to separate particulate organic matter (POM) from mineral compartments. We especially aimed at obtaining the combined fine silt and clay fraction which is thought to be most important in the long term stabilization of SOM. The chemical composition of the so obtained fractions and the bulk soil was revealed by C, N and 13C CPMAS NMR measurements. The source of OM in the soil was investigated by tracing the biopolymers cutin and suberin across the soil profile. Cutin occurs mainly in the cuticula of leaves while suberin mainly constitutes the endodermal cell walls of plant roots. In soils the two polymers can thus be used as proxies for above and belowground OM input respectively. To release the constituting monomers of the two biopolymers from the soil samples the latter were pretreated with organic solvents to extract free lipids. The soil residues were subsequently subjected to a base hydrolysis and the so obtained extracts were measured with GC/MS. The organic C contents of the bulk soil decrease significantly with depth in all transects from around 15 mg g-1 to 2 mg g-1. This is likely associated with the very high sand and low clay concentrations and the decreasing POM content at greater depths in the soil profiles. The highest C contents were found in the POM fractions with 400 mg g-1 and the combined fine silt and clay fractions with 6 mg g-1. Interestingly the NMR spectra display an already highly processed POM in the uppermost soil horizon as indicated by high alkyl/O-alkyl C ratios. This, together with the absence of POM in greater depths, points towards a decomposition of aboveground OM predominantly in the upper zones of the soil and a confined root input to deeper soil regions.
Auger electron spectroscopy and depth profile study of oxidation of modified 440C steel
NASA Technical Reports Server (NTRS)
Ferrante, J.
1974-01-01
Auger electron spectroscopy (AES) and sputtering were used to study selective oxidation of modified 440C steel. The sample was polycrystalline. Oxidation was performed on initially clean surfaces for pressures ranging from 1 x 10 to the minus 7th power to 1 x 10 to the minus 5th power torr and temperatures ranging from room temperature to 800 C. AES traces were taken during oxidation. In situ sputtering depth profiles are also obtained. A transition temperature is observed in the range 600 to 700 C for which the composition of the outer surface oxide changed from iron oxide to chromium oxide. Heating in vacuum about 5 x 10 to the minus 10 power torr to 700 C causes conversion of the iron oxide surface to chromium oxide.
Chemosensory characteristics of regional Vidal icewines from China and Canada.
Huang, Ling; Ma, Yue; Tian, Xin; Li, Ji-Ming; Li, Lan-Xiao; Tang, Ke; Xu, Yan
2018-09-30
This work aimed to compare the flavor characteristics of Vidal icewines from China and Canada and to establish relationships between sensory descriptors and chemical composition. Descriptive analysis was performed with a trained panel to obtain the sensory profiles. Thirty important aroma-active compounds were quantified by four different methodologies. Partial least squares discriminant analysis was used to identify candidate compounds, which were unique to certain sensory descriptors. The sensory profiles of icewines from China were characterized by nut and honey aromas, while icewines from Canada expressed caramel and rose aromas. Nut and honey aromas had a close correlation with 1-hexanol, isoamyl acetate, phenethyl acetate and phenylethyl alcohol. Caramel aroma was correlated with ethyl esters and lactones and rose aroma was correlated with terpenes. Copyright © 2018 Elsevier Ltd. All rights reserved.
Titan's Upper Atmosphere from Cassini/UVIS Solar Occultations
NASA Astrophysics Data System (ADS)
Capalbo, Fernando J.; Bénilan, Yves; Yelle, Roger V.; Koskinen, Tommi T.
2015-12-01
Titan’s atmosphere is composed mainly of molecular nitrogen, methane being the principal trace gas. From the analysis of 8 solar occultations measured by the Extreme Ultraviolet channel of the Ultraviolet Imaging Spectrograph (UVIS) on board Cassini, we derived vertical profiles of N2 in the range 1100-1600 km and vertical profiles of CH4 in the range 850-1300 km. The correction of instrument effects and observational effects applied to the data are described. We present CH4 mole fractions, and average temperatures for the upper atmosphere obtained from the N2 profiles. The occultations correspond to different times and locations, and an analysis of variability of density and temperature is presented. The temperatures were analyzed as a function of geographical and temporal variables, without finding a clear correlation with any of them, although a trend of decreasing temperature toward the north pole was observed. The globally averaged temperature obtained is (150 ± 1) K. We compared our results from solar occultations with those derived from other UVIS observations, as well as studies performed with other instruments. The observational data we present confirm the atmospheric variability previously observed, add new information to the global picture of Titan’s upper atmosphere composition, variability, and dynamics, and provide new constraints to photochemical models.
Simone, Giuseppe Vasile; Montevecchi, Giuseppe; Masino, Francesca; Matrella, Valentina; Imazio, Serena Anna; Antonelli, Andrea; Bignami, Cristina
2013-11-01
'Saba' and 'agresto' are traditional Italian products both based on unfermented grape juices that are concentrated by heating. The former is obtained from ripe grapes and the latter from unripe grapes. In this work, we have characterized the main red-skinned (Ancellotta, Fortana, Lambrusco di Sorbara, Lambrusco grasparossa, Lambrusco salamino and Uva Tosca) and white-skinned (Lugliatica, Spergola, Trebbiano di Spagna and Trebbiano modenese) cultivars used for 'saba' and 'agresto' production, focusing on the variability expressed by ampelographic traits, physical and chemical parameters and anthocyanin profile. The cultivars examined were effectively discriminated on the basis of their different composition profile by analysis of variance and principal component analysis. In particular, a peculiar anthocyanin profile was traced by absolute and relative values for each cultivar. The identification of the main anthocyanins of some local cultivars, their chemical characterization and their ampelographic description were one of the main achievements of this work. The use of red grapes to obtain 'saba' seems more rational for the presence of higher amounts of antioxidant substances. Ancellotta showed several factors interesting for 'saba' production, such as the very high anthocyanin content, including anthocyanin antioxidants. A more detailed investigation on 'agresto' technology is required. © 2013 Society of Chemical Industry.
NASA Astrophysics Data System (ADS)
Münch, Thomas; Kipfstuhl, Sepp; Freitag, Johannes; Meyer, Hanno; Laepple, Thomas
2017-09-01
The isotopic composition of water in ice sheets is extensively used to infer past climate changes. In low-accumulation regions their interpretation is, however, challenged by poorly constrained effects that may influence the initial isotope signal during and after deposition of the snow. This is reflected in snow-pit isotope data from Kohnen Station, Antarctica, which exhibit a seasonal cycle but also strong interannual variations that contradict local temperature observations. These inconsistencies persist even after averaging many profiles and are thus not explained by local stratigraphic noise. Previous studies have suggested that post-depositional processes may significantly influence the isotopic composition of East Antarctic firn. Here, we investigate the importance of post-depositional processes within the open-porous firn (≳ 10 cm depth) at Kohnen Station by separating spatial from temporal variability. To this end, we analyse 22 isotope profiles obtained from two snow trenches and examine the temporal isotope modifications by comparing the new data with published trench data extracted 2 years earlier. The initial isotope profiles undergo changes over time due to downward advection, firn diffusion and densification in magnitudes consistent with independent estimates. Beyond that, we find further modifications of the original isotope record to be unlikely or small in magnitude (≪ 1 ‰ RMSD). These results show that the discrepancy between local temperatures and isotopes most likely originates from spatially coherent processes prior to or during deposition, such as precipitation intermittency or systematic isotope modifications acting on drifting or loose surface snow.
Port, Jesse A; Wallace, James C; Griffith, William C; Faustman, Elaine M
2012-01-01
Human-health relevant impacts on marine ecosystems are increasing on both spatial and temporal scales. Traditional indicators for environmental health monitoring and microbial risk assessment have relied primarily on single species analyses and have provided only limited spatial and temporal information. More high-throughput, broad-scale approaches to evaluate these impacts are therefore needed to provide a platform for informing public health. This study uses shotgun metagenomics to survey the taxonomic composition and antibiotic resistance determinant content of surface water bacterial communities in the Puget Sound estuary. Metagenomic DNA was collected at six sites in Puget Sound in addition to one wastewater treatment plant (WWTP) that discharges into the Sound and pyrosequenced. A total of ~550 Mbp (1.4 million reads) were obtained, 22 Mbp of which could be assembled into contigs. While the taxonomic and resistance determinant profiles across the open Sound samples were similar, unique signatures were identified when comparing these profiles across the open Sound, a nearshore marina and WWTP effluent. The open Sound was dominated by α-Proteobacteria (in particular Rhodobacterales sp.), γ-Proteobacteria and Bacteroidetes while the marina and effluent had increased abundances of Actinobacteria, β-Proteobacteria and Firmicutes. There was a significant increase in the antibiotic resistance gene signal from the open Sound to marina to WWTP effluent, suggestive of a potential link to human impacts. Mobile genetic elements associated with environmental and pathogenic bacteria were also differentially abundant across the samples. This study is the first comparative metagenomic survey of Puget Sound and provides baseline data for further assessments of community composition and antibiotic resistance determinants in the environment using next generation sequencing technologies. In addition, these genomic signals of potential human impact can be used to guide initial public health monitoring as well as more targeted and functionally-based investigations.
The Analytical Limits of Modeling Short Diffusion Timescales
NASA Astrophysics Data System (ADS)
Bradshaw, R. W.; Kent, A. J.
2016-12-01
Chemical and isotopic zoning in minerals is widely used to constrain the timescales of magmatic processes such as magma mixing and crystal residence, etc. via diffusion modeling. Forward modeling of diffusion relies on fitting diffusion profiles to measured compositional gradients. However, an individual measurement is essentially an average composition for a segment of the gradient defined by the spatial resolution of the analysis. Thus there is the potential for the analytical spatial resolution to limit the timescales that can be determined for an element of given diffusivity, particularly where the scale of the gradient approaches that of the measurement. Here we use a probabilistic modeling approach to investigate the effect of analytical spatial resolution on estimated timescales from diffusion modeling. Our method investigates how accurately the age of a synthetic diffusion profile can be obtained by modeling an "unknown" profile derived from discrete sampling of the synthetic compositional gradient at a given spatial resolution. We also include the effects of analytical uncertainty and the position of measurements relative to the diffusion gradient. We apply this method to the spatial resolutions of common microanalytical techniques (LA-ICP-MS, SIMS, EMP, NanoSIMS). Our results confirm that for a given diffusivity, higher spatial resolution gives access to shorter timescales, and that each analytical spacing has a minimum timescale, below which it overestimates the timescale. For example, for Ba diffusion in plagioclase at 750 °C timescales are accurate (within 20%) above 10, 100, 2,600, and 71,000 years at 0.3, 1, 5, and 25 mm spatial resolution, respectively. For Sr diffusion in plagioclase at 750 °C, timescales are accurate above 0.02, 0.2, 4, and 120 years at the same spatial resolutions. Our results highlight the importance of selecting appropriate analytical techniques to estimate accurate diffusion-based timescales.
Karaçalı, Bilge; Vamvakidou, Alexandra P; Tözeren, Aydın
2007-01-01
Background Three-dimensional in vitro culture of cancer cells are used to predict the effects of prospective anti-cancer drugs in vivo. In this study, we present an automated image analysis protocol for detailed morphological protein marker profiling of tumoroid cross section images. Methods Histologic cross sections of breast tumoroids developed in co-culture suspensions of breast cancer cell lines, stained for E-cadherin and progesterone receptor, were digitized and pixels in these images were classified into five categories using k-means clustering. Automated segmentation was used to identify image regions composed of cells expressing a given biomarker. Synthesized images were created to check the accuracy of the image processing system. Results Accuracy of automated segmentation was over 95% in identifying regions of interest in synthesized images. Image analysis of adjacent histology slides stained, respectively, for Ecad and PR, accurately predicted regions of different cell phenotypes. Image analysis of tumoroid cross sections from different tumoroids obtained under the same co-culture conditions indicated the variation of cellular composition from one tumoroid to another. Variations in the compositions of cross sections obtained from the same tumoroid were established by parallel analysis of Ecad and PR-stained cross section images. Conclusion Proposed image analysis methods offer standardized high throughput profiling of molecular anatomy of tumoroids based on both membrane and nuclei markers that is suitable to rapid large scale investigations of anti-cancer compounds for drug development. PMID:17822559
The failure of 1D seismic model fitting to constrain lower mantle composition
NASA Astrophysics Data System (ADS)
Houser, C. T.; Hernlund, J. W.; Valencia-Cardona, J. J.; Wentzcovitch, R.
2017-12-01
Tests of lower mantle composition models often compare mineral physics data bearing on the elasticity and density of lower mantle phases to the average seismic velocity profile determined by seismology, such a PREM or ak135. We demonstrate why such comparisons between mineralogy and seismology are an inadequate method for definitive discrimination between different scenarios. One issue is that the seismic velocity is more sensitive to temperature than composition for most lower mantle minerals. In practice, this allows one the freedom to choose the geotherm that brings the predicted seismic and density data into agreement with observations. It is commonly assumed that the temperature profile should be adiabatic, however, such a profile presupposes a particular state of the mantle and is only applicable in the absence of layering, buoyancy fluctuations, compositional segregation, and rheological complexities. The mantle temperature should depend on the composition since the latter influences the viscosity of rocks. However, the precise relation between composition, viscosity, and heat transfer would need to be specified, but unfortunately remains highly uncertain. If the mantle contains a mixture of domains with multiple bulk compositions, then the 1D seismic profile comparison is inherently non-unique. Rocks with different bulk composition likely have different isotopic abundances, and can exhibit differing degrees of internal heating and therefore distinct temperatures. Different composition domains can also exhibit variable densities, and tend to congregate at different depths in ways that also affect their thermal evolution and temperature. Therefore, fitting a 1D seismic model alone is an inadequate tool to evaluate lower mantle composition.
High-resolution passive sampling of dissolved methane in the water column of lakes in Greenland
NASA Astrophysics Data System (ADS)
Goldman, A. E.; Cadieux, S. B.; White, J. R.; Pratt, L. M.
2013-12-01
Arctic lakes are important participants in the global carbon cycle, releasing methane in a warming climate and contributing to a positive feedback to climate change. In order to yield detailed methane budgets and understand the implications of warming on methane dynamics, high-resolution profiles revealing methane behavior within the water column need to be obtained. Single day sampling using disruptive techniques has the potential to result in biases. In order to obtain high-resolution, undisturbed profiles of methane concentration and isotopic composition, this study evaluates a passive sampling method over a multi-day equilibration period. Selected for this study were two small lakes (<1km2) within a narrow valley stretching between Russells Glacier and Søndre Strømfjord in southwestern Greenland, which are part of an ongoing study of a series of seven lakes. Commercially available, 150 mL, polyethylene Passive Diffusion Bags (PDB's) were deployed in July 2013 for five days at 0.5-meter depth intervals. PDB samples were compared to samples collected with a submersible, electric pump taken immediately before PBD deployment. Preliminary CH4 concentrations and carbon isotopes for one lake were obtained in the field using a Los Gatos Research Methane Carbon Isotope Analyzer. PDB sampling and pump sampling resulted in statistically similar concentrations (R2=0.89), ranging from 0.85 to 135 uM from PDB and 0.74 to 143 uM from pump sampling. In anoxic waters of the lake, where concentrations were high enough to yield robust isotopic results on the LGR MCIA, δ13C were also similar between the two methods, yielding -73‰ from PDB and -74‰ from pump sampling. Further investigation will produce results for a second lake and methane carbon and hydrogen isotopic composition for both lakes. Preliminary results for this passive sampling method are promising. We envision the use of this technique in future studies of dissolved methane and expect that it will provide a more finely resolved vertical profile, allowing for a more complete understanding of lacustrine methane dynamics.
NASA Astrophysics Data System (ADS)
Dyroff, C.; Sanati, S.; Christner, E.; Zahn, A.; Balzer, M.; Bouquet, H.; McManus, J. B.; González-Ramos, Y.; Schneider, M.
2015-01-01
Vertical profiles of water vapor (H2O) and its isotope ratio D / H expressed as δ D(H2O were measured in situ by the ISOWAT II diode-laser spectrometer during the MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA) airborne campaign. We present recent modifications of the instrument design. The instrument calibration on the ground as well as in flight is described. Based on the calibration measurements, the humidity-dependent uncertainty of our airborne data is determined. For the majority of the airborne data we achieved an accuracy (uncertainty of the mean) of Δ(δ D) ≈ 10‰. Vertical profiles between 150 and ~7000 m were obtained during 7 days in July and August 2013 over the subtropical North Atlantic Ocean near Tenerife. The flights were coordinated with ground-based (Network for the Detection of Atmospheric Composition Change, NDACC) and space-based (Infrared Atmospheric Sounding Interferometer, IASI) FTIR remote-sensing measurements of δ D(H2O) as a means to validate the remote sensing humidity and δ D(H2O) data products. The results of the validation are presented in detail in a separate paper (Schneider et al., 2014). The profiles were obtained with a high vertical resolution of around 3 m. By analyzing humidity and δ D(H2O) correlations we were able to identify different layers of airmasses with specific isotopic signatures. The results are discussed.
Ogura, Tatsuki; Date, Yasuhiro; Kikuchi, Jun
2013-01-01
Because they are strong and stable, lignocellulosic supramolecular structures in plant cell walls are resistant to decomposition. However, they can be degraded and recycled by soil microbiota. Little is known about the biomass degradation profiles of complex microbiota based on differences in cellulosic supramolecular structures without compositional variations. Here, we characterized and evaluated the cellulosic supramolecular structures and composition of rice straw biomass processed under different milling conditions. We used a range of techniques including solid- and solution-state nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy followed by thermodynamic and microbial degradability characterization using thermogravimetric analysis, solution-state NMR, and denaturing gradient gel electrophoresis. These measured data were further analyzed using an “ECOMICS” web-based toolkit. From the results, we found that physical pretreatment of rice straw alters the lignocellulosic supramolecular structure by cleaving significant molecular lignocellulose bonds. The transformation from crystalline to amorphous cellulose shifted the thermal degradation profiles to lower temperatures. In addition, pretreated rice straw samples developed different microbiota profiles with different metabolic dynamics during the biomass degradation process. This is the first report to comprehensively characterize the structure, composition, and thermal degradation and microbiota profiles using the ECOMICS toolkit. By revealing differences between lignocellulosic supramolecular structures of biomass processed under different milling conditions, our analysis revealed how the characteristic compositions of microbiota profiles develop in addition to their metabolic profiles and dynamics during biomass degradation. PMID:23840554
NASA Astrophysics Data System (ADS)
Sauzède, R.; Lavigne, H.; Claustre, H.; Uitz, J.; Schmechtig, C.; D'Ortenzio, F.; Guinet, C.; Pesant, S.
2015-10-01
In vivo chlorophyll a fluorescence is a proxy of chlorophyll a concentration, and is one of the most frequently measured biogeochemical properties in the ocean. Thousands of profiles are available from historical databases and the integration of fluorescence sensors to autonomous platforms has led to a significant increase of chlorophyll fluorescence profile acquisition. To our knowledge, this important source of environmental data has not yet been included in global analyses. A total of 268 127 chlorophyll fluorescence profiles from several databases as well as published and unpublished individual sources were compiled. Following a robust quality control procedure detailed in the present paper, about 49 000 chlorophyll fluorescence profiles were converted into phytoplankton biomass (i.e., chlorophyll a concentration) and size-based community composition (i.e., microphytoplankton, nanophytoplankton and picophytoplankton), using a method specifically developed to harmonize fluorescence profiles from diverse sources. The data span over 5 decades from 1958 to 2015, including observations from all major oceanic basins and all seasons, and depths ranging from the surface to a median maximum sampling depth of around 700 m. Global maps of chlorophyll a concentration and phytoplankton community composition are presented here for the first time. Monthly climatologies were computed for three of Longhurst's ecological provinces in order to exemplify the potential use of the data product. Original data sets (raw fluorescence profiles) as well as calibrated profiles of phytoplankton biomass and community composition are available on open access at PANGAEA, Data Publisher for Earth and Environmental Science. Raw fluorescence profiles: http://doi.pangaea.de/10.1594/PANGAEA.844212 and Phytoplankton biomass and community composition: http://doi.pangaea.de/10.1594/PANGAEA.844485
A risk-based approach to management of leachables utilizing statistical analysis of extractables.
Stults, Cheryl L M; Mikl, Jaromir; Whelehan, Oliver; Morrical, Bradley; Duffield, William; Nagao, Lee M
2015-04-01
To incorporate quality by design concepts into the management of leachables, an emphasis is often put on understanding the extractable profile for the materials of construction for manufacturing disposables, container-closure, or delivery systems. Component manufacturing processes may also impact the extractable profile. An approach was developed to (1) identify critical components that may be sources of leachables, (2) enable an understanding of manufacturing process factors that affect extractable profiles, (3) determine if quantitative models can be developed that predict the effect of those key factors, and (4) evaluate the practical impact of the key factors on the product. A risk evaluation for an inhalation product identified injection molding as a key process. Designed experiments were performed to evaluate the impact of molding process parameters on the extractable profile from an ABS inhaler component. Statistical analysis of the resulting GC chromatographic profiles identified processing factors that were correlated with peak levels in the extractable profiles. The combination of statistically significant molding process parameters was different for different types of extractable compounds. ANOVA models were used to obtain optimal process settings and predict extractable levels for a selected number of compounds. The proposed paradigm may be applied to evaluate the impact of material composition and processing parameters on extractable profiles and utilized to manage product leachables early in the development process and throughout the product lifecycle.
Real-Gas Effects on Binary Mixing Layers
NASA Technical Reports Server (NTRS)
Okong'o, Nora; Bellan, Josette
2003-01-01
This paper presents a computational study of real-gas effects on the mean flow and temporal stability of heptane/nitrogen and oxygen/hydrogen mixing layers at supercritical pressures. These layers consist of two counterflowing free streams of different composition, temperature, and density. As in related prior studies reported in NASA Tech Briefs, the governing conservation equations were the Navier-Stokes equations of compressible flow plus equations for the conservation of total energy and of chemical- species masses. In these equations, the expressions for heat fluxes and chemical-species mass fluxes were derived from fluctuation-dissipation theory and incorporate Soret and Dufour effects. Similarity equations for the streamwise velocity, temperature, and mass fractions were derived as approximations to the governing equations. Similarity profiles showed important real-gas, non-ideal-mixture effects, particularly for temperature, in departing from the error-function profile, which is the similarity solution for incompressible flow. The temperature behavior was attributed to real-gas thermodynamics and variations in Schmidt and Prandtl numbers. Temporal linear inviscid stability analyses were performed using the similarity and error-function profiles as the mean flow. For the similarity profiles, the growth rates were found to be larger and the wavelengths of highest instability shorter, relative to those of the errorfunction profiles and to those obtained from incompressible-flow stability analysis. The range of unstable wavelengths was found to be larger for the similarity profiles than for the error-function profiles
NASA Astrophysics Data System (ADS)
Mulia, Kamarza; Halimah, Nur; Krisanti, Elsa
2017-03-01
Preparation of mangostin-loaded chitosan-alginate microparticles, chemical and physical characterization of the particles, and mangostin release profiles, are described herein. Mangostin rich fraction was obtained from Garcinia mangostana L. pericarp by extraction followed by fractionation. Mangostin-loaded chitosan-alginate microparticles were prepared by ionic gelation method using tripolyphosphate as the linking agent and various concentration of alginate. Mangostin was effectively loaded in all microparticle formulations, resulting in ˜97% encapsulation efficiencies. The loading of mangostin and the in-vitro release profiles in simulated gastrointestinal fluids were affected by the chitosan to alginate ratios used in the preparation of the microparticles. Increased alginate concentration resulted in lowered release of mangostin from microparticles immersed in simulated gastric fluid (pH 1.2) up to two hours. Low release of mangostin in acidic fluid but high release in simulated colon fluid, indicated that the chitosan-alginate microparticles are prospective carrier for extended release of active compound in gastrointestinal system.
NASA Technical Reports Server (NTRS)
Hung, R. J.; Liaw, G. S.
1980-01-01
The effects of multi-disperse distribution of the aerosol population are presented. Single component and multi-component aerosol species on the condensation/nucleation processes which affect the reduction in visibility are described. The aerosol population with a high particle concentration provided more favorable conditions for the formation of a denser fog than the aerosol population with a greater particle size distribution when the value of the mass concentration of the aerosols was kept constant. The results were used as numerical predictions of fog formation. Two dimensional observations in horizontal and vertical coordinates, together with time-dependent measurements were needed as initial values for the following physical parameters: (1)wind profiles; (2) temperature profiles; (3) humidity profiles; (4) mass concentration of aerosol particles; (5) particle size distribution of aerosols; and (6) chemical composition of aerosols. Formation and dissipation of advection fog, thus, can be forecasted numerically by introducing initial values obtained from the observations.
Tejerina, D; García-Torres, S; de Vaca, M Cabeza; Vázquez, F M; Cava, R
2012-02-01
This investigation was designed to evaluate the effects of variations in antioxidant and fatty acids composition of acorns and grass from two Montanera (free-range system and feeding based on acorns and grass) seasons (2006/07 and 2007/08) on the antioxidant composition and fatty acids profile of m. Longissimus dorsi (LD) and m. Serratus ventralis (SV) from Iberian pigs reared under these Montanera seasons. Acorn and grass composition was affected by Montanera season and consequently, LD and SV muscles showed different contents of α-tocopherol, total phenols, hydrophilic and lipophilic antioxidant activity and fatty acid profile, according with the composition of acorns and grass ingested. Results suggest a lack of uniformity in meat quality between different seasons. This could be due to the variable nature of extensive pig production as reflected in the variability in the composition of the diet (acorns and grass). Copyright © 2011 Elsevier Ltd. All rights reserved.
Surface emission from neutron stars and implications for the physics of their interiors.
Ozel, Feryal
2013-01-01
Neutron stars are associated with diverse physical phenomena that take place in conditions characterized by ultrahigh densities as well as intense gravitational, magnetic and radiation fields. Understanding the properties and interactions of matter in these regimes remains one of the challenges in compact object astrophysics. Photons emitted from the surfaces of neutron stars provide direct probes of their structure, composition and magnetic fields. In this review, I discuss in detail the physics that governs the properties of emission from the surfaces of neutron stars and their various observational manifestations. I present the constraints on neutron star radii, core and crust composition, and magnetic field strength and topology obtained from studies of their broadband spectra, evolution of thermal luminosity, and the profiles of pulsations that originate on their surfaces.
Depth profile by Total IBA in perovskite active layers for solar cells
NASA Astrophysics Data System (ADS)
Barreiros, M. A.; Alves, L. C.; Brites, M. J.; Corregidor, V.
2017-08-01
In recent years the record efficiency of perovskite solar cells (PSCs) has been updated exceeding now 20%. However, it is difficult to make PSCs consistently. Definite correlation has been established between the PSC performance and the perovskite film quality which involves mainly morphology, crystallinity and composition. The manufacturing development of these devices is dependent on the characterisation methodologies, on the availability of suitable and reliable analytical techniques to assess the materials composition and quality and on the relationship of these results with the cell performance. Ion beam analytical (IBA) techniques jointly with a micro-ion beam are powerful tools for materials characterisation and can provide a valuable input for the knowledge of perovskite films. Perovskite films based on CH3NH3PbI3 were prepared (from CH3NH3I and PbI2 precursors) in a planar architecture and in a mesoporous TiO2 scaffold. Proton and helium micro-beams at different energies were used in the analysis of PSC active layers, previously characterised by SEM-FEG (Scanning Electron Microscopy with a field emission gun) and XRD (X-ray diffraction). Self-consistent fit of all the obtained PIXE (Particle Induced X-ray Emission) and RBS (Rutherford Backscattering Spectrometry) spectra through Total IBA approach provided depth profiling of perovskite, its precursors and TiO2 and assess their distribution in the films. PbI2 presence and location on the active layer may hinder the charge transport and highly affect the cell performance. IBA techniques allowed to identify regions of non-uniform surface coverage and homogeneous areas and it was possible to establish the undesired presence of PbI2 and its quantitative depth profile in the planar architecture film. In the mesostructured perovskite film it was verified a non-homogeneous distribution with a decreasing of perovskite concentration down to the thin blocking layer. The good agreement between the best fits obtained in a Total IBA approach and the experimental data granted reliability to depth profile results for the studied perovskite films.
TRACKING CHLORDANE COMPOSITIONAL AND CHIRAL PROFILES IN SOIL AND VEGETATION. (R828174)
The cycling of chlordane and other persistent organic pollutants through the environment must be comprehensively elucidated to assess adequately the human health risks posed from such contaminants. In this study the compositional and chiral profiles of weathered chlordane resi...
Shiwa, Yuh; Hachiya, Tsuyoshi; Furukawa, Ryohei; Ohmomo, Hideki; Ono, Kanako; Kudo, Hisaaki; Hata, Jun; Hozawa, Atsushi; Iwasaki, Motoki; Matsuda, Koichi; Minegishi, Naoko; Satoh, Mamoru; Tanno, Kozo; Yamaji, Taiki; Wakai, Kenji; Hitomi, Jiro; Kiyohara, Yutaka; Kubo, Michiaki; Tanaka, Hideo; Tsugane, Shoichiro; Yamamoto, Masayuki; Sobue, Kenji; Shimizu, Atsushi
2016-01-01
Differences in DNA collection protocols may be a potential confounder in epigenome-wide association studies (EWAS) using a large number of blood specimens from multiple biobanks and/or cohorts. Here we show that pre-analytical procedures involved in DNA collection can induce systematic bias in the DNA methylation profiles of blood cells that can be adjusted by cell-type composition variables. In Experiment 1, whole blood from 16 volunteers was collected to examine the effect of a 24 h storage period at 4°C on DNA methylation profiles as measured using the Infinium HumanMethylation450 BeadChip array. Our statistical analysis showed that the P-value distribution of more than 450,000 CpG sites was similar to the theoretical distribution (in quantile-quantile plot, λ = 1.03) when comparing two control replicates, which was remarkably deviated from the theoretical distribution (λ = 1.50) when comparing control and storage conditions. We then considered cell-type composition as a possible cause of the observed bias in DNA methylation profiles and found that the bias associated with the cold storage condition was largely decreased (λadjusted = 1.14) by taking into account a cell-type composition variable. As such, we compared four respective sample collection protocols used in large-scale Japanese biobanks or cohorts as well as two control replicates. Systematic biases in DNA methylation profiles were observed between control and three of four protocols without adjustment of cell-type composition (λ = 1.12–1.45) and no remarkable biases were seen after adjusting for cell-type composition in all four protocols (λadjusted = 1.00–1.17). These results revealed important implications for comparing DNA methylation profiles between blood specimens from different sources and may lead to discovery of disease-associated DNA methylation markers and the development of DNA methylation profile-based predictive risk models. PMID:26799745
Shiwa, Yuh; Hachiya, Tsuyoshi; Furukawa, Ryohei; Ohmomo, Hideki; Ono, Kanako; Kudo, Hisaaki; Hata, Jun; Hozawa, Atsushi; Iwasaki, Motoki; Matsuda, Koichi; Minegishi, Naoko; Satoh, Mamoru; Tanno, Kozo; Yamaji, Taiki; Wakai, Kenji; Hitomi, Jiro; Kiyohara, Yutaka; Kubo, Michiaki; Tanaka, Hideo; Tsugane, Shoichiro; Yamamoto, Masayuki; Sobue, Kenji; Shimizu, Atsushi
2016-01-01
Differences in DNA collection protocols may be a potential confounder in epigenome-wide association studies (EWAS) using a large number of blood specimens from multiple biobanks and/or cohorts. Here we show that pre-analytical procedures involved in DNA collection can induce systematic bias in the DNA methylation profiles of blood cells that can be adjusted by cell-type composition variables. In Experiment 1, whole blood from 16 volunteers was collected to examine the effect of a 24 h storage period at 4°C on DNA methylation profiles as measured using the Infinium HumanMethylation450 BeadChip array. Our statistical analysis showed that the P-value distribution of more than 450,000 CpG sites was similar to the theoretical distribution (in quantile-quantile plot, λ = 1.03) when comparing two control replicates, which was remarkably deviated from the theoretical distribution (λ = 1.50) when comparing control and storage conditions. We then considered cell-type composition as a possible cause of the observed bias in DNA methylation profiles and found that the bias associated with the cold storage condition was largely decreased (λ adjusted = 1.14) by taking into account a cell-type composition variable. As such, we compared four respective sample collection protocols used in large-scale Japanese biobanks or cohorts as well as two control replicates. Systematic biases in DNA methylation profiles were observed between control and three of four protocols without adjustment of cell-type composition (λ = 1.12-1.45) and no remarkable biases were seen after adjusting for cell-type composition in all four protocols (λ adjusted = 1.00-1.17). These results revealed important implications for comparing DNA methylation profiles between blood specimens from different sources and may lead to discovery of disease-associated DNA methylation markers and the development of DNA methylation profile-based predictive risk models.
Processing and Properties of a Phenolic Composite System
NASA Technical Reports Server (NTRS)
Hou, Tan-Hung; Bai, J. M.; Baughman, James M.
2006-01-01
Phenolic resin systems generate water as a reaction by-product via condensation reactions during curing at elevated temperatures. In the fabrication of fiber reinforced phenolic resin matrix composites, volatile management is crucial in producing void-free quality laminates. A commercial vacuum-bag moldable phenolic prepreg system was selected for this study. The traditional single-vacuum-bag (SVB) process was unable to manage the volatiles effectively, resulting in inferior voidy laminates. However, a double vacuum bag (DVB) process was shown to afford superior volatile management and consistently yielded void-free quality parts. The DVB process cure cycle (temperature /pressure profiles) for the selected composite system was designed, with the vacuum pressure application point carefully selected, to avoid excessive resin squeeze-outs and achieve the net shape and target resin content in the final consolidated laminate parts. Laminate consolidation quality was characterized by optical photomicrography for the cross sections and measurements of mechanical properties. A 40% increase in short beam shear strength, 30% greater flexural strength, 10% higher tensile and 18% higher compression strengths were obtained in composite laminates fabricated by the DVB process.
Characterization of Hg1-xCdxTe heterostructures by thermoelectric measurements
NASA Astrophysics Data System (ADS)
Baars, J.; Brink, D.; Edwall, D. D.; Bubulac, L. O.
1993-08-01
P-on-n mercury cadmium telluride (MCT) heterostructures grown by MOCVD with As and In as n- and p-type dopants, respectively, are examined by measuring the Seebeck and Hall coefficients between 20 and 320K. The results are analyzed regarding doping and composition of the layers by least squares fitting the experimental profiles with the calculated temperature dependencies. The electron and hole densities of the layers are calculated taking into account Fermi-Dirac statistics, a nonparabolic conduction band, a parabolic valence band, a discrete acceptor level, and fully ionized donors. For the Seebeck coefficient, the relation we previously showed to be valid for p-type MCT1 is used. This relation relies on the thermoelectric effect in a temperature gradient resulting from the diffusion of nondegenerate carriers scattered by LO-phonons. It also fits the observed thermoelectric properties of n-type MCT in a wide temperature range. The doping and structural parameters determined from the thermoelectric measurements agreed very well with As and In profiles obtained from secondary ion mass spectroscopy measurements and the data obtained from analyses of infrared transmission measurements.
Rodríguez-Nogales, J M; Vivar-Quintana, A M; Revilla, I
2007-07-01
Bulk tank ewe milk from the Assaf, Castellana, and Churra breeds categorized into 3 somatic cell count (SCC) groups (<500,000; 1,000,000 to 1,500,000; and >2,500,000 cells/mL) was used to investigate changes in chemical composition and capillary electrophoresis protein profiles. The results obtained indicated that breed affected fat, protein, and total solids levels, and differences were also observed for the following milk proteins: beta-, beta1-, beta2-, and alpha(s1)-III-casein, alpha-lactalbumin, and beta-lactoglobulin. High SCC affected fat and protein contents and bacterial counts. The level of beta1-, beta2-, and alpha(s1)-I-casein, and alpha-lactalbumin were significantly lower in milk with SCC scores >2,500,000 cells/mL. A preliminary study of the chemical, microbiological, and electrophoretic data was performed by cluster analysis and principal components analysis. Applying discriminant analysis, it was possible to group the milk samples according to breed and level of SCC, obtaining a prediction of 100 and 97% of the samples, respectively.
Metabolite Profiling and Classification of DNA-Authenticated Licorice Botanicals
Simmler, Charlotte; Anderson, Jeffrey R.; Gauthier, Laura; Lankin, David C.; McAlpine, James B.; Chen, Shao-Nong; Pauli, Guido F.
2015-01-01
Raw licorice roots represent heterogeneous materials obtained from mainly three Glycyrrhiza species. G. glabra, G. uralensis, and G. inflata exhibit marked metabolite differences in terms of flavanones (Fs), chalcones (Cs), and other phenolic constituents. The principal objective of this work was to develop complementary chemometric models for the metabolite profiling, classification, and quality control of authenticated licorice. A total of 51 commercial and macroscopically verified samples were DNA authenticated. Principal component analysis and canonical discriminant analysis were performed on 1H NMR spectra and area under the curve values obtained from UHPLC-UV chromatograms, respectively. The developed chemometric models enable the identification and classification of Glycyrrhiza species according to their composition in major Fs, Cs, and species specific phenolic compounds. Further key outcomes demonstrated that DNA authentication combined with chemometric analyses enabled the characterization of mixtures, hybrids, and species outliers. This study provides a new foundation for the botanical and chemical authentication, classification, and metabolomic characterization of crude licorice botanicals and derived materials. Collectively, the proposed methods offer a comprehensive approach for the quality control of licorice as one of the most widely used botanical dietary supplements. PMID:26244884
Di Lecce, Giuseppe; Arranz, Sara; Jáuregui, Olga; Tresserra-Rimbau, Anna; Quifer-Rada, Paola; Lamuela-Raventós, Rosa M
2014-02-15
This paper describes for the first time a complete characterisation of the phenolic compounds in different anatomical parts of the Albariño grape. The application of high-performance liquid chromatography coupled with two complementary techniques, hybrid quadrupole time-of-flight and triple-quadrupole mass spectrometry, allowed the phenolic composition of the Albariño grape to be unambiguously identified and quantified. A more complete phenolic profile was obtained by product ion and precursor ion scans, while a neutral loss scan at 152 u enabled a fast screening of procyanidin dimers, trimers and their galloylated derivatives. The compounds were confirmed by accurate mass measurements in QqToF-MS and QqToF-MS/MS modes at high resolution, and good fits were obtained for all investigated ions, with errors ranging from 0.2 to 4.5 mDa. To the best of our knowledge, two flavanol monomer hexosides were detected in the grape berry for the first time. Copyright © 2013 Elsevier Ltd. All rights reserved.
Mineral composition of lunar late mare volcanism revealed from Kaguya SP data
NASA Astrophysics Data System (ADS)
Kato, S.; Morota, T.; Yamaguchi, Y.; Watanabe, S.; Otake, H.; Ohtake, M.; Nimura, T.
2017-12-01
Lunar mare basalts provide insights into the composition and thermal history of the lunar mantle. According to previous studies of crater counting analysis using remote sensing data, the ages of mare basalts suggest a first peak of magma activity at 3.2-3.8 Ga and a second peak at 2 Ga. To understand the mechanism for causing the second peak and its magma source is essential to constrain the thermal history of the lunar mantle. In our previous study [Kato et al., 2017], we reassess the correlation between the titanium contents and the eruption ages of mare basalt units using the compositional and chronological data updated by SELENE (Kaguya). The results show a rapid increase in mean titanium content near 2.3 Ga in the Procellarum KREEP Terrane (PKT), where the latest eruptions are concentrated. Moreover, the high-titanium basaltic eruptions are correlated with the second peak in volcanic activity at 2 Ga. Here we designate volcanisms before and after 2.3 Ga as Phase-1 and Phase-2 volcanism. To understand the mechanism of Phase-2 mare volcanism and its magma source, determining the mineral components and elemental compositions of mare basalts in the PKT is important. Nimura [2011] improved the modified Gaussian model (MGM) [Sunshine et al., 1990] by obtaining the relations between chemical compositions of minerals (the ratio of Fe/(Fe+Mg) in olivine and the ratios of Ca/(Ca+Fe+Mg) and Fe/(Ca+Fe+Mg) in pyroxene) and absorption band parameters (center, width and strength ratio of Gaussian curves). In this study, we re-derived the relations using experimental spectral data and applied the method to spectral data of mare basalts obtained by Kaguya Spectral Profiler (SP) to estimate the mineral components and elemental compositions of lunar mare basalts.
Moghaddam, Maryam Kahali; Breede, Arne; Brauner, Christian; Lang, Walter
2015-03-27
The production of large and complex parts using fiber composite materials is costly due to the frequent formation of voids, porosity and waste products. By embedding different types of sensors and monitoring the process in real time, the amount of wastage can be significantly reduced. This work focuses on developing a knowledge-based method to improve and ensure complete impregnation of the fibers before initiation of the resin cure. Piezoresistive and capacitive pressure sensors were embedded in fiber composite laminates to measure the real-time the pressure values inside the laminate. A change of pressure indicates resin infusion. The sensors were placed in the laminate and the resin was infused by vacuum. The embedded piezoresistive pressure sensors were able to track the vacuum pressure in the fiber composite laminate setup, as well as the arrival of the resin at the sensor. The pressure increase due to closing the resin inlet was also measured. In contrast, the capacitive type of sensor was found to be inappropriate for measuring these quantities. The following study demonstrates real-time monitoring of pressure changes inside the fiber composite laminate, which validate the use of Darcy's law in porous media to control the resin flow during infusion.
Satyal, Prabodh; Craft, Jonathan D.; Dosoky, Noura S.; Setzer, William N.
2017-01-01
Garlic, Allium sativum, is broadly used around the world for its numerous culinary and medicinal uses. Wild garlic, Allium vineale, has been used as a substitute for garlic, both in food as well as in herbal medicine. The present study investigated the chemical compositions of A. sativum and A. vineale essential oils. The essential oils from the bulbs of A. sativum, cultivated in Spain, were obtained by three different methods: laboratory hydrodistillation, industrial hydrodistillation, and industrial steam distillation. The essential oils of wild-growing A. vineale from north Alabama were obtained by hydrodistillation. The resulting essential oils were analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Both A. sativum and A. vineale oils were dominated by allyl polysulfides. There were minor quantitative differences between the A. sativum oils owing to the distillation methods employed, as well as differences from previously reported garlic oils from other geographical locations. Allium vineale oil showed a qualitative similarity to Allium ursinum essential oil. The compositions of garlic and wild garlic are consistent with their use as flavoring agents in foods as well as their uses as herbal medicines. However, quantitative differences are likely to affect the flavor and bioactivity profiles of these Allium species. PMID:28783070
Satyal, Prabodh; Craft, Jonathan D; Dosoky, Noura S; Setzer, William N
2017-08-05
Garlic, Allium sativum , is broadly used around the world for its numerous culinary and medicinal uses. Wild garlic, Allium vineale , has been used as a substitute for garlic, both in food as well as in herbal medicine. The present study investigated the chemical compositions of A. sativum and A. vineale essential oils. The essential oils from the bulbs of A. sativum , cultivated in Spain, were obtained by three different methods: laboratory hydrodistillation, industrial hydrodistillation, and industrial steam distillation. The essential oils of wild-growing A. vineale from north Alabama were obtained by hydrodistillation. The resulting essential oils were analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Both A. sativum and A. vineale oils were dominated by allyl polysulfides. There were minor quantitative differences between the A. sativum oils owing to the distillation methods employed, as well as differences from previously reported garlic oils from other geographical locations. Allium vineale oil showed a qualitative similarity to Allium ursinum essential oil. The compositions of garlic and wild garlic are consistent with their use as flavoring agents in foods as well as their uses as herbal medicines. However, quantitative differences are likely to affect the flavor and bioactivity profiles of these Allium species.
Gómez García-Carpintero, E; Gómez Gallego, M A; Sánchez-Palomo, E; González Viñas, M A
2012-09-15
This paper reports on a complete study of the effect of wood, in the form of oak chips, on the volatile composition and sensory characteristics of Moravia Agria wines added at different stages of the fermentation process. Aroma compounds were analyzed by gas chromatography-mass spectrometry (GC-MS). Sensory profile was evaluated by experienced wine-testers. Oak chips were added to wines in two dose rates at different stages of the winemaking process: during alcoholic fermentation (AF), during malolactic fermentation (MLF) and in young, red Moravia Agria wine. Wines fermented with oak chips during AF showed higher concentrations of the ethyl esters of straight-chain fatty acids, ethyl, hexyl, isoamyl acetates and superior alcohols than the control wines. The higher concentrations of benzene compound, oak lactones and furanic compounds were found in wines in contact with oak chips during MLF. The use of oak chips gives rise to a different sensorial profile of wines depending of the point of addition. Higher intensities of woody, coconut, vanilla and sweet spices descriptors were obtained when a large dose rate of chips was employed. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Hashim, Noor Haslinda Noor; Latip, Jalifah; Khatib, Alfi
2016-11-01
The metabolites of Clinacanthus nutans leaves extracts and their dependence on drying process were systematically characterized using 1H nuclear magnetic resonance spectroscopy (NMR) multivariate data analysis. Principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) were able to distinguish the leaves extracts obtained from different drying methods. The identified metabolites were carbohydrates, amino acid, flavonoids and sulfur glucoside compounds. The major metabolites responsible for the separation in PLS-DA loading plots were lupeol, cycloclinacosides, betulin, cerebrosides and choline. The results showed that the combination of 1H NMR spectroscopy and multivariate data analyses could act as an efficient technique to understand the C. nutans composition and its variation.
Qi, Yujun; Xiong, Wei; Liu, Weiqing; Fang, Hai; Lu, Weidong
2015-01-01
The plate of a pultruded fiber-reinforced polymer or fiber-reinforced plastic (FRP) profile produced via a pultrusion process is likely to undergo local buckling and cracking along the fiber direction under an external load. In this study, we constructed a pultruded glass-fiber-reinforced polymer-light wood composite (PGWC) profile to explore its mechanical performance. A rectangular cross-sectional PGWC profile was fabricated with a paulownia wood core, alkali-free glass fiber filaments, and unsaturated phthalate resin. Three-point bending and short column axial compression tests were conducted. Then, the stress calculation for the PGWC profile in the bending and axial compression tests was performed using the Timoshenko beam theory and the composite component analysis method to derive the flexural and axial compression rigidity of the profile during the elastic stress stage. The flexural capacity for this type of PGWC profile is 3.3-fold the sum of the flexural capacities of the wood core and the glass-fiber-reinforced polymer (GFRP) shell. The equivalent flexural rigidity is 1.5-fold the summed flexural rigidity of the wood core and GFRP shell. The maximum axial compressive bearing capacity for this type of PGWC profile can reach 1.79-fold the sum of those of the wood core and GFRP shell, and its elastic flexural rigidity is 1.2-fold the sum of their rigidities. These results indicate that in PGWC profiles, GFRP and wood materials have a positive combined effect. This study produced a pultruded composite material product with excellent mechanical performance for application in structures that require a large bearing capacity.
Qi, Yujun; Xiong, Wei; Liu, Weiqing; Fang, Hai; Lu, Weidong
2015-01-01
The plate of a pultruded fiber-reinforced polymer or fiber-reinforced plastic (FRP) profile produced via a pultrusion process is likely to undergo local buckling and cracking along the fiber direction under an external load. In this study, we constructed a pultruded glass-fiber-reinforced polymer-light wood composite (PGWC) profile to explore its mechanical performance. A rectangular cross-sectional PGWC profile was fabricated with a paulownia wood core, alkali-free glass fiber filaments, and unsaturated phthalate resin. Three-point bending and short column axial compression tests were conducted. Then, the stress calculation for the PGWC profile in the bending and axial compression tests was performed using the Timoshenko beam theory and the composite component analysis method to derive the flexural and axial compression rigidity of the profile during the elastic stress stage. The flexural capacity for this type of PGWC profile is 3.3-fold the sum of the flexural capacities of the wood core and the glass-fiber-reinforced polymer (GFRP) shell. The equivalent flexural rigidity is 1.5-fold the summed flexural rigidity of the wood core and GFRP shell. The maximum axial compressive bearing capacity for this type of PGWC profile can reach 1.79-fold the sum of those of the wood core and GFRP shell, and its elastic flexural rigidity is 1.2-fold the sum of their rigidities. These results indicate that in PGWC profiles, GFRP and wood materials have a positive combined effect. This study produced a pultruded composite material product with excellent mechanical performance for application in structures that require a large bearing capacity. PMID:26485431
Felfel, R M; Ahmed, I; Parsons, A J; Walker, G S; Rudd, C D
2011-10-01
Several studies have investigated self-reinforced polylactic acid (SR-PLA) and polyglycolic acid (SR-PGA) rods which could be used as intramedullary (IM) fixation devices to align and stabilise bone fractures. This study investigated totally bioresorbable composite rods manufactured via compression moulding at ~100 °C using phosphate glass fibres (of composition 50P(2)O(5)-40CaO-5Na(2)O-5Fe(2)O(3) in mol%) to reinforce PLA with an approximate fibre volume fraction (v(f)) of 30%. Different fibre architectures (random and unidirectional) were investigated and pure PLA rods were used as control samples. The degradation profiles and retention of mechanical properties were investigated and PBS was selected as the degradation medium. Unidirectional (P50 UD) composite rods had 50% higher initial flexural strength as compared to PLA and 60% higher in comparison to the random mat (P50 RM) composite rods. Similar initial profiles for flexural modulus were also seen comparing the P50 UD and P50 RM rods. Higher shear strength properties were seen for P50 UD in comparison to P50 RM and PLA rods. However, shear stiffness values decreased rapidly (after a week) whereas the PLA remained approximately constant. For the compressive strength studies, P50 RM and PLA rods remained approximately constant, whilst for the P50 UD rods a significantly higher initial value was obtained, which decreased rapidly after 3 days immersion in PBS. However, the mechanical properties decreased after immersion in PBS as a result of the plasticisation effect of water within the composite and degradation of the fibres. The fibres within the random and unidirectional composite rods (P50 RM and P50 UD) degraded leaving behind microtubes as seen from the SEM micrographs (after 28 days degradation) which in turn created a porous structure within the rods. This was the main reason attributed for the increase seen in mass loss and water uptake for the composite rods (~17% and ~16%, respectively). Copyright © 2011 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Harb, M. S.; Yuan, F. G.
2015-03-01
Conventional ultrasound inspection has been a standard non-destructive testing method for providing an in-service evaluation and noninvasive means of probing the interior of a structure. In particular, measurement of the propagation characteristics of Lamb waves allows inspection of plates that are typical components in aerospace industry. A rapid, complete non-contact hybrid approach for excitation and detection of Lamb waves is presented and applied for non-destructive evaluation of composites. An air-coupled transducer (ACT) excites ultrasonic waves on the surface of a composite plate, generating different propagating Lamb wave modes and a laser Doppler vibrometer (LDV) is used to measure the out-of-plane velocity of the plate. This technology, based on direct waveform imaging, focuses on measuring dispersive curves for A0 mode in a composite laminate and its anisotropy. A two-dimensional fast Fourier transform (2D-FFT) is applied to out-of-plane velocity data captured experimentally using LDV to go from the time-spatial domain to frequency-wavenumber domain. The result is a 2D array of amplitudes at discrete frequencies and wavenumbers for A0 mode in a given propagation direction along the composite. The peak values of the curve are then used to construct frequency wavenumber and phase velocity dispersion curves, which are also obtained directly using Snell's law and the incident angle of the excited ultrasonic waves. A high resolution and strong correlation between numerical and experimental results are observed for dispersive curves with Snell's law method in comparison to 2D-FFT method. Dispersion curves as well as velocity curves for the composite plate along different directions of wave propagation are measured. The visual read-out of the dispersion curves at different propagation directions as well as the phase velocity curves provide profiling and measurements of the composite anisotropy. The results proved a high sensitivity of the air-coupled and laser ultrasound technique in non-contact characterization of Lamb wave dispersion and material anisotropy of composite plates using simple Snell's law method.
X-ray Photoelectron Spectroscopy of High-κ Dielectrics
NASA Astrophysics Data System (ADS)
Mathew, A.; Demirkan, K.; Wang, C.-G.; Wilk, G. D.; Watson, D. G.; Opila, R. L.
2005-09-01
Photoelectron spectroscopy is a powerful technique for the analysis of gate dielectrics because it can determine the elemental composition, the chemical states, and the compositional depth profiles non-destructively. The sampling depth, determined by the escape depth of the photoelectrons, is comparable to the thickness of current gate oxides. A maximum entropy algorithm was used to convert photoelectron collection angle dependence of the spectra to compositional depth profiles. A nitrided hafnium silicate film is used to demonstrate the utility of the technique. The algorithm balances deviations from a simple assumed depth profile against a calculated depth profile that best fits the angular dependence of the photoelectron spectra. A flow chart of the program is included in this paper. The development of the profile is also shown as the program is iterated. Limitations of the technique include the electron escape depths and elemental sensitivity factors used to calculate the profile. The technique is also limited to profiles that extend to the depth of approximately twice the escape depth. These limitations restrict conclusions to comparison among a family of similar samples. Absolute conclusions about depths and concentrations must be used cautiously. Current work to improve the algorithm is also described.
Erosion of fluorinated diamond-like carbon films by exposure to soft X-rays
NASA Astrophysics Data System (ADS)
Kanda, Kazuhiro; Takamatsu, Hiroki; Miura-Fujiwara, Eri; Akasaka, Hiroki; Saiga, Akihiro; Tamada, Koji
2018-04-01
The effects of soft X-ray irradiation on fluorinated diamond-like carbon (F-DLC) films were investigated using synchrotron radiation (SR). The Vickers hardness of the F-DLC films substantially increased from an initial value of about 290 to about 800 HV at a dose of 50 mA·h and the remained constant at about 1100 HV at doses of more than 300 mA·h. This dose dependence was consistent with those of the film thickness and elemental composition. The depth profile of the elemental composition inside each F-DLC film obtained by the measurement of the X-ray photoelectron spectrum (XPS) during sputtering showed that the composition ratio of fluorine was approximately constant from the surface to the neighborhood of the substrate. Namely, fluorine atoms were desorbed by SR irradiation from not only the surface but also the substrate neighborhood. Modification by SR irradiation was found to occur in the entire F-DLC film of about 200 nm thickness.
de Melo, Nathalie Ferreira Silva; Grillo, Renato; Guilherme, Viviane Aparecida; de Araujo, Daniele Ribeiro; de Paula, Eneida; Rosa, André Henrique; Fraceto, Leonardo Fernandes
2011-08-01
The aim of this work was to investigate the influence of the oily nucleus composition on physico-chemical properties and anesthetic activity of poly (lactide-co-glycolide) nanocapsules with benzocaine. Nanocapsules containing benzocaine were prepared with three different oily nucleus composition and characterized by mean diameter, polydispersivity, zeta potential, pH and stability were investigated as a function of time. In vitro release kinetics were performed in a system with two compartments separated by a cellulose membrane. Intensity and duration of analgesia were evaluated in rats by sciatic nerve blockade. The greatest stability, slower release profile and improvement in the local anesthetic activity of BZC were obtained with the formulation using USP mineral oil as component. Results from our study provide useful perspectives on selection of the primary materials needed to produce suspensions of polymeric nanocapsules able to act as carriers of BZC, with potential future application in the treatment of pain.
Tannin profile of different Monastrell wines and its relation to projected market prices.
Gómez-Plaza, Encarna; Olmos, Oscar; Bautista-Ortín, Ana Belén
2016-08-01
This study focuses on the differences or similarities in tannin composition and concentration in Monastrell wines from different wineries from the same geographic area and, within each winery, from wines elaborated based on different projected market prices, to determine whether there is any relationship between the wine tannin composition and the projected price. The tannin composition of the different wines, all of them analyzed at the same point during winemaking, indicated that those elaborated as premium wines presented higher phenol and tannin contents. The mean degree of polymerization of these wines was also positively related with the projected price, which agreed with the results obtained by size exclusion chromatography, that showed that wines with high projected prices had a higher proportion of polymeric tannins, suggesting that techniques favoring the extraction of skin tannins were mostly used in those wines projected as premium wines, probably looking for greater mouthfeel complexity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Pérez, Concepción; Ruiz del Castillo, María Luisa; Gil, Carmen; Blanch, Gracia Patricia; Flores, Gema
2015-08-01
Grape by-products are a rich source of bioactive compounds having broad medicinal properties, but are usually wasted from juice/wine processing industries. The present study investigates the use of supercritical fluid extraction (SFE) for obtaining an extract rich in bioactive compounds. First, some variables involved in the extraction were applied. SFE conditions were selected based on the oil mass yield, fatty acid profile and total phenolic composition. As a result, 40 °C and 300 bar were selected as operational conditions. The phenolic composition of the grape seed oil was determined using LC-DAD. The antioxidant activity was determined by ABTS and DPPH assays. For the anti-inflammatory activity the inhibition of nitrite production was assessed. The grape seed oil extracted was rich in phenolic compounds and fatty acids with significant antioxidant and anti-inflammatory activities. From these results, added economic value to this agroindustrial residue is proposed using environmentally friendly techniques.
Chemical composition of the essential oil of Stachys menthifolia Vis.
Ćavar, Sanja; Maksimović, Milka; Vidic, Danijela; Šolić, Marija Edita
2010-02-01
Stachys menthifolia Vis. (Lamiaceae) is an endemic species from the Balkan Peninsula spread throughout Albania, Greece, Montenegro, and Croatia. This article presents the first investigation of the essential oil composition of this species from Croatia. Aerial parts of the plant were collected from three different natural habitats in the region of Biokovo Mountain. The studied populations showed similarity in qualitative, but not in quantitative, composition of their essential oils. Hydrodistilled volatile oil obtained from the plant material of S. menthifolia was subjected to gas chromatographic analysis coupled to mass spectrometry. More than 100 compounds were identified in the three samples, representing 86.8-90.8% of the total oil. The terpene profile of S. menthifolia is characterized by a high content of oxygenated sesquiterpenes (48.4-58.9%) and diterpene hydrocarbons (3.5-25.2%), with 8-alpha-acetoxyelemol (6.9-21.3%), abietatriene (3.5-21.1%), and 4'-methoxyacetophenone (4.5-17.0%) as the main constituents.
A study of the feasibility of ultraviolet spectrometry for cometary missions
NASA Technical Reports Server (NTRS)
Feldman, P. D.
1979-01-01
Ultraviolet spectra fo the comet West obtained by sounding rocket experiments in 1976 are reproduced and interpreted in order to estimate the expected brightness of the emission features and determine the spatial extent of these features for the proposed Halley Flyby/Tempel 2 rendezvous and the possible Halley or Encke flybys close to perihelion. A coma model was constructed and evaluated for the physical condition of candidate targets such as heliocentric distance, gas production, and composition. In addition to brightness profiles, the neutral and ion densities of the principal species are also dervied. The brightness profiles can be used to determine the feasibility of utilizing the space telescope to provide supporting observations during the mission. Basic parameters identified are spectral range, wavelength resolution, spatial resolution, sensitivity and dynamic range, rejection of scattered light, and integration or accumulation time.
Jang, Yun Jung; Lee, Jihye; Jeong, Jeung-Hyun; Lee, Kang-Bong; Kim, Donghwan; Lee, Yeonhee
2018-05-01
To enhance the conversion performance of solar cells, a quantitative and depth-resolved elemental analysis of photovoltaic thin films is required. In this study, we determined the average concentration of the major elements (Cu, In, Ga, and Se) in fabricated Cu(In,Ga)Se2 (CIGS) thin films, using inductively coupled plasma atomic emission spectroscopy, X-ray fluorescence, and wavelengthdispersive electron probe microanalysis. Depth profiling results for CIGS thin films with different cell efficiencies were obtained using secondary ion mass spectrometry and Auger electron spectroscopy to compare the atomic concentrations. Atom probe tomography, a characterization technique with sub-nanometer resolution, was used to obtain three-dimensional elemental mapping and the compositional distribution at the grain boundaries (GBs). GBs are identified by Na increment accompanied by Cu depletion and In enrichment. Segregation of Na atoms along the GB had a beneficial effect on cell performance. Comparative analyses of different CIGS absorber layers using various analytical techniques provide us with understanding of the compositional distributions and structures of high efficiency CIGS thin films in solar cells.
Benincasa, Cinzia; Gharsallaoui, Mariem; Perri, Enzo; Briccoli Bati, Caterina; Ayadi, Mohamed; Khlif, Moncen; Gabsi, Slimane
2012-01-01
In the present work the use of treated wastewater (TWW) to irrigate olive plants was monitored. This type of water is characterized by high salinity and retains a substantial amount of trace elements, organic and metallic compounds that can be transferred into the soil and into the plants and fruits. In order to evaluate the impact of TWW on the overall quality of the oils, the time of contact of the olives with the soil has been taken into account. Multi-element data were obtained using ICP-MS. Nineteen elements (Li, B, Na, Mg, Al, K, Ca, Sc, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Mo, Ba and La) were submitted for statistical analysis. Using analysis of variance, linear discriminant analysis and principal component analysis it was possible to differentiate between oils produced from different batches of olives whose plants received different types of water. Also, the results showed that there was correlation between the elemental and mineral composition of the water used to irrigate the olive plots and the elemental and mineral composition of the oils. PMID:22654625
Synthesis and piezoelectric properties of (1 - x)Bi0.5(Na0.8K0.2)0.5TiO3-xSr2ZrTiO6 ceramics
NASA Astrophysics Data System (ADS)
Onishi, Ryo; Ogawa, Hirotaka; Iida, Daiki; Kan, Akinori
2017-10-01
The effects of Sr2ZrTiO6 (SZT) addition on the piezoelectric properties of (1 - x)Bi0.5(Na0.8K0.2)0.5TiO3 (BNKT)-xSZT ceramics were characterized in this study. The X-ray powder diffraction (XRPD) profiles and Raman spectra of the ceramics in the composition range of 0-0.02 implies the presence of morphotropic phase boundary (MPB) which consists of the rhombohedral and tetragonal phases. Moreover, the temperature dependence of dielectric loss indicated a presence of the ferroelectric-relaxor transition temperature (T F-R) of around 75 °C for x = 0.005 and the temperature dependence shifted to a lower temperature at x = 0.01. The temperature dependence of the P-E hysteresis loop of the ceramics at the compositions of x = 0.005-0.02 showed pinched hysteresis loops above T F-R. Regarding the piezoelectric constant (d 33), it was increased by SZT addition in the MPB region (x = 0-0.01) and the highest d 33 of 202 pC/N was obtained at the composition of x = 0.0025. The S-E unipolar loop was also evaluated, the strain of the ceramic increased up to x = 0.02; and the highest d33* = 436 pm/V was obtained at the composition of x = 0.02.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ferreira, M.O.M.; de Sousa, P.T.; Salvador, V.L.R.
The Anadenathera macrocarpa, Schinus molle, Hymenaea courbaril, Cariniana legalis, Solidago microglossa and Stryphnodendron barbatiman, were collected ''in natura'' samples (leaves, flowers, barks and seeds) from different commercial suppliers. The pharmaco-active compounds in ethanolic extracts had been made by the Mato Grosso Federal University (UFMT). The energy-dispersive x-ray fluorescence (ED-XRF) spectrometry was used for the elemental analysis in different parts of the plants and respective ethanolic extracts. The Ca, Cl, Cu, Fe, K, Mg, Mn, Na, Ni, P, Rb, S, Sr and Zn concentrations were determined by the fundamental parameters method. Some specimens showed a similar inorganic profile for ''in natura''more » and ethanolic extract samples and some ones showed a distinct inorganic profile. For example, the Anadenathera macrocarpa showed a similar concentration in Mg, P, Cu, Zn and Rb elements in ''in natura'' and ethanolic extract samples; however very different concentration in Na, S, Cl, K , Ca, Mn, Fe and Sr was observed in distinctive samples. The Solidago microglossa showed the K, Ca, Cl, S, Mg, P and Fe elements as major constituents in both samples, suggesting that the extraction process did not affect in a considerable way the ''in natura'' inorganic composition. The elemental composition of the different parts of the plants (leaves, flowers, barks and seeds) has been also determined. For example, the Schinus molle specimen showed P, K, Cl and Ca elements as major constituents in the seeds, Mg, K and Sr in the barks and Mg, S, Cl and Mn in the leaves, demonstrating a differentiated elementary distribution. These inorganic profiles will contribute to evaluate the quality control of the Brazilian herbaceous trade and also will assist to identify which parts of the medicinal plants has greater therapeutic effect.« less
Distribution of CO2 in Saturn's Atmosphere from Cassini/cirs Infrared Observations
NASA Astrophysics Data System (ADS)
Abbas, M. M.; LeClair, A.; Woodard, E.; Young, M.; Stanbro, M.; Flasar, F. M.; Kunde, V. G.; Achterberg, R. K.; Bjoraker, G.; Brasunas, J.; Jennings, D. E.; the Cassini/CIRS Team
2013-10-01
This paper focuses on the CO2 distribution in Saturn's atmosphere based on analysis of infrared spectral observations of Saturn made by the Composite Infrared Spectrometer aboard the Cassini spacecraft. The Cassini spacecraft was launched in 1997 October, inserted in Saturn's orbit in 2004 July, and has been successfully making infrared observations of Saturn, its rings, Titan, and other icy satellites during well-planned orbital tours. The infrared observations, made with a dual Fourier transform spectrometer in both nadir- and limb-viewing modes, cover spectral regions of 10-1400 cm-1, with the option of variable apodized spectral resolutions from 0.53 to 15 cm-1. An analysis of the observed spectra with well-developed radiative transfer models and spectral inversion techniques has the potential to provide knowledge of Saturn's thermal structure and composition with global distributions of a series of gases. In this paper, we present an analysis of a large observational data set for retrieval of Saturn's CO2 distribution utilizing spectral features of CO2 in the Q-branch of the ν2 band, and discuss its possible relationship to the influx of interstellar dust grains. With limited spectral regions available for analysis, due to low densities of CO2 and interference from other gases, the retrieved CO2 profile is obtained as a function of a model photochemical profile, with the retrieved values at atmospheric pressures in the region of ~1-10 mbar levels. The retrieved CO2 profile is found to be in good agreement with the model profile based on Infrared Space Observatory measurements with mixing ratios of ~4.9 × 10-10 at atmospheric pressures of ~1 mbar.
Albertini, Beatrice; Melegari, Cecilia; Bertoni, Serena; Dolci, Luisa Stella; Passerini, Nadia
2018-04-01
The objective of this study was to assess the efficacy and the capability of a novel ethylcellulose-based dry-coating system to obtain prolonged and stable release profiles of caffeine-loaded pellets. Lauric and oleic acids at a suitable proportion were used to plasticize ethylcellulose. The effect of coating level, percentage of drug loading, inert core particle size, and composition of the coating formulation including the anti-sticking agent on the drug release profile were fully investigated. A coating level of 15% w/w was the maximum layered amount which could modify the drug release. The best controlled drug release was obtained by atomizing talc (2.5% w/w) together with the solid plasticizer during the dry powder-coating process. SEM pictures revealed a substantial drug re-crystallization on the pellet surface, and the release studies evidenced that caffeine diffused through the plasticized polymer acting as pore former. Therefore, the phenomenon of caffeine migration across the coating layer had a strong influence on the permeability of the coating membrane. Comparing dry powder-coated pellets to aqueous film-coated ones, drug migration happened during storage, though more sustained release profiles were obtained. The developed dry powder-coating process enabled the production of stable caffeine sustained release pellets. Surprisingly, the release properties of the dry-coated pellets were mainly influenced by the way of addition of talc into the dry powder-coating blend and by the drug nature and affinity to the coating components. It would be interesting to study the efficacy of novel coating system using a different API.
A stochastic model for optimizing composite predictors based on gene expression profiles.
Ramanathan, Murali
2003-07-01
This project was done to develop a mathematical model for optimizing composite predictors based on gene expression profiles from DNA arrays and proteomics. The problem was amenable to a formulation and solution analogous to the portfolio optimization problem in mathematical finance: it requires the optimization of a quadratic function subject to linear constraints. The performance of the approach was compared to that of neighborhood analysis using a data set containing cDNA array-derived gene expression profiles from 14 multiple sclerosis patients receiving intramuscular inteferon-beta1a. The Markowitz portfolio model predicts that the covariance between genes can be exploited to construct an efficient composite. The model predicts that a composite is not needed for maximizing the mean value of a treatment effect: only a single gene is needed, but the usefulness of the effect measure may be compromised by high variability. The model optimized the composite to yield the highest mean for a given level of variability or the least variability for a given mean level. The choices that meet this optimization criteria lie on a curve of composite mean vs. composite variability plot referred to as the "efficient frontier." When a composite is constructed using the model, it outperforms the composite constructed using the neighborhood analysis method. The Markowitz portfolio model may find potential applications in constructing composite biomarkers and in the pharmacogenomic modeling of treatment effects derived from gene expression endpoints.
Duval, Joseph S.
1995-01-01
This CD-ROM contains images generated from geophysical data, software for displaying and analyzing the images and software for displaying and examining profile data from aerial surveys flown as part of the National Uranium Resource Evaluation (NURE) Program of the U.S. Department of Energy. The images included are of gamma-ray data (uranium, thorium, and potassium channels), Bouguer gravity data, isostatic residual gravity data, aeromagnetic anomalies, topography, and topography with bathymetry. This publication contains image data for the conterminous United States and profile data for the conterminous United States within the area longitude 108 to 126 degrees W. and latitude 34 to 49 degrees N. The profile data include apparent surface concentrations of potassium, uranium, and thorium, the residual magnetic field, and the height above the ground. The images on this CD-ROM include graytone and color images of each data set, color shaded-relief images of the potential-field and topographic data, and color composite images of the gamma-ray data. The image display and analysis software can register images with geographic and geologic overlays. The profile display software permits the user to view the profiles as well as obtain data listings and export ASCII versions of data for selected flight lines.
Abundance and Temperature Variations in Titan's Atmosphere as Revealed by ALMA
NASA Astrophysics Data System (ADS)
Thelen, A. E.; Nixon, C. A.; Chanover, N.; Molter, E.; Cordiner, M. A.; Serigano, J., IV; Irwin, P. G.; Charnley, S. B.; Teanby, N. A.
2016-12-01
Photochemistry in Titan's atmosphere produces a wealth of organic molecular species through the dissociation of it's main constituents: N2 and CH4. Chemical species including hydrocarbons (CXHY) and nitriles (CXHY[CN]Z) exhibit latitudinal variations in abundance as observed by Cassini, attributed to atmospheric circulation and Titan's seasonal cycle. Flux calibration images of Titan taken by the Atacama Large Millimeter/Submillimeter Array (ALMA) with beam sizes smaller than Titan's angular diameter ( 0.7'') allow for measurements of rotational transition lines in spatially resolved regions of Titan's disk. We present nitrile abundance profiles and temperature measurements derived from CO lines obtained by ALMA in 2014, as Titan transitioned into northern summer. Vertical profiles in Titan's lower/middle atmosphere were retrieved by modeling high resolution ALMA spectra using the Non-linear Optimal Estimator for MultivariatE Spectral analySIS (NEMESIS) radiative transfer code. We present a comparison of the abundance variations of chemical species to measurements made using Cassini data. Temperature profiles derived from CO lines are compared to Cassini Composite Infrared Spectrometer temperature fields. The techniques presented here will allow us to determine temporal changes in Titan's atmospheric chemical composition after the end of the Cassini mission by utilizing high resolution ALMA data. Comparisons of chemical species with strong abundance enhancements over the poles will inform our knowledge of chemical lifetimes in Titan's atmosphere, and allow us to observe the important changes in production and circulation of numerous organic molecules which are attributed to Titan's seasons.
Depciuch, J; Kasprzyk, I; Roga, E; Parlinska-Wojtan, M
2016-11-01
Nowadays, pollen allergy becomes an increasing problem for human population. Common mugwort (Artemisia vulgaris L.) is one of the major allergenic plants in Europe. In this study, the influence of air pollution caused by traffic on the structure and chemical composition of common mugwort pollen was investigated. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and curve-fitting analysis of amide I profile was applied to assess the morphological and structural changes of mugwort pollen grains collected from sites with different vehicle pollution levels. Microscopic observations support the conclusion, that the higher the car traffic, the smaller the pollen grains. The obtained results clearly show that air pollution had an impact on different maximum absorbance values of individual functional groups composing the chemical structure of pollen. Moreover, air pollution induced structural changes in macromolecules of mugwort pollen. In pollen collected from the unpolluted site, the content of sporopollenin (850 cm -1 ) was the highest, whereas polysaccharide concentration (1032 cm -1 ) was the lowest. Significant differences were observed in lipids. Pollen collected from the site with heavy traffic had the lowest content of lipids at 1709, 2071, and 2930 cm -1 . The largest differences were observed in the spectra regions corresponding to proteins. In pollen collected from unpolluted site, the highest level of β-sheet (1600 cm -1 ) and α-helix (1650 cm -1 ) was detected. The structural changes in proteins, observed in the second derivative of the FTIR spectrum and in the curve-fitting analysis of amide I profile, could be caused inter alia by air pollutants. Alterations in protein structure and in their content in the pollen may increase the sensitization and subsequent risk of allergy in predisposed people. The obtained results suggest that the changes in chemical composition of pollen may be a good indicator of air quality and that FTIR may be successfully applied in biomonitoring.
NASA Astrophysics Data System (ADS)
Qian, Gang; Feng, Yi; Li, Bin; Huang, Shiyin; Liu, Hongjuan; Ding, Kewang
2013-03-01
As the traditional graphite-based composites cannot meet the requirement of rapid developing modern industry, novel sliding electrical contact materials with high self-lubricating performance in multiple environments are eagerly required. Herein a copper-based composite with WS2 and graphite as solid lubricant are fabricated by powder metallurgy hot-pressed method. The friction and wear behaviors of the composites with and without current are investigated under the condition with sliding velocity of 10 m/s and normal load of 2.5 N/cm2 in both air and vacuum. Morphologies of the worn surfaces are observed by optical microscope and compositions of the lubricating films are analyzed by XPS. Surface profile curves and roughness of the worn surfaces are obtained by 2205 surface profiler. The results of wear tests show that the friction coefficient and wear volume loss of the composites with current are greater than that without current in both air and vacuum due to the adverse effects of electrical current which damaged the lubricating film partially and roughed the worn surfaces. XPS results demonstrate that the lubricating film formed in air is composed of oxides of Cu, WS2, elemental S and graphite, while the lubricating film formed in vacuum is composed of Cu, WS2 and graphite. Because of the synergetic lubricating action of oxides of Cu, WS2 and graphite, the composites show low friction coefficient and wear volume loss in air condition. Owing to the fact that graphite loses its lubricity which makes WS2 become the only lubricant, severe adhesive and abrasive wear occur and result in a high value of wear rate in vacuum condition. The formation of the lubricating film on the contact interface between the brush and ring is one of the factors which can greatly affect the wear performance of the brushes. The low contact voltage drop of the composites in vacuum condition is attributed to the high content of Cu in the surface film. This study fabricated a kind of new sliding electrical contact self-lubricating composite with dual-lubricant which can work well in both air and vacuum environments and provides a comprehensive analysis on the lubrication mechanisms of the composite.
Modeling of crack bridging in a unidirectional metal matrix composite
NASA Technical Reports Server (NTRS)
Ghosn, Louis J.; Kantzos, Pete; Telesman, Jack
1991-01-01
The effective fatigue crack driving force and crack opening profiles were determined analytically for fatigue tested unidirectional composite specimens exhibiting fiber bridging. The crack closure pressure due to bridging was modeled using two approaches; the fiber pressure model and the shear lag model. For both closure models, the Bueckner weight function method and the finite element method were used to calculate crack opening displacements and the crack driving force. The predicted near crack tip opening profile agreed well with the experimentally measured profiles for single edge notch SCS-6/Ti-15-3 metal matrix composite specimens. The numerically determined effective crack driving force, Delta K(sup eff), was calculated using both models to correlate the measure crack growth rate in the composite. The calculated Delta K(sup eff) from both models accounted for the crack bridging by showing a good agreement between the measured fatigue crack growth rates of the bridged composite and that of unreinforced, unbridged titanium matrix alloy specimens.
Modeling of crack bridging in a unidirectional metal matrix composite
NASA Technical Reports Server (NTRS)
Ghosn, Louis J.; Kantzos, Pete; Telesman, Jack
1992-01-01
The effective fatigue crack driving force and crack opening profiles were determined analytically for fatigue tested unidirectional composite specimens exhibiting fiber bridging. The crack closure pressure due to bridging was modeled using two approaches: the fiber pressure model and the shear lag model. For both closure models, the Bueckner weight function method and the finite element method were used to calculate crack opening displacements and the crack driving force. The predicted near crack tip opening profile agreed well with the experimentally measured profiles for single edge notch SCS-6/Ti-15-3 metal matrix composite specimens. The numerically determined effective crack driving force, Delta K(eff), was calculated using both models to correlate the measure crack growth rate in the composite. The calculated Delta K(eff) from both models accounted for the crack bridging by showing a good agreement between the measured fatigue crack growth rates of the bridged composite and that of unreinforced, unbridged titanium matrix alloy specimens.
NASA Astrophysics Data System (ADS)
Gholamhoseini, Alireza
2016-03-01
Relatively little research has been reported on the time-dependent in-service behavior of composite concrete slabs with profiled steel decking as permanent formwork and little guidance is available for calculating long-term deflections. The drying shrinkage profile through the thickness of a composite slab is greatly affected by the impermeable steel deck at the slab soffit, and this has only recently been quantified. This paper presents the results of long-term laboratory tests on composite slabs subjected to both drying shrinkage and sustained loads. Based on laboratory measurements, a design model for the shrinkage strain profile through the thickness of a slab is proposed. The design model is based on some modifications to an existing creep and shrinkage prediction model B3. In addition, an analytical model is developed to calculate the time-dependent deflection of composite slabs taking into account the time-dependent effects of creep and shrinkage. The calculated deflections are shown to be in good agreement with the experimental measurements.
Danoix, F; Grancher, G; Bostel, A; Blavette, D
2007-09-01
Atom probe is a very powerful instrument to measure concentrations on a sub nanometric scale [M.K. Miller, G.D.W. Smith, Atom Probe Microanalysis, Principles and Applications to Materials Problems, Materials Research Society, Pittsburgh, 1989]. Atom probe is therefore a unique tool to study and characterise finely decomposed metallic materials. Composition profiles or 3D mapping can be realised by gathering elemental composition measurements. As the detector efficiency is generally not equal to 1, the measured compositions are only estimates of actual values. The variance of the estimates depends on which information is to be estimated. It can be calculated when the detection process is known. These two papers are devoted to give complete analytical derivation and expressions of the variance on composition measurements in several situations encountered when using atom probe. In the first paper, we will concentrate on the analytical derivation of the variance when estimation of compositions obtained from a conventional one dimension (1D) atom probe is considered. In particular, the existing expressions, and the basic hypotheses on which they rely, will be reconsidered, and complete analytical demonstrations established. In the second companion paper, the case of 3D atom probe will be treated, highlighting how the knowledge of the 3D position of detected ions modifies the analytical derivation of the variance of local composition data.
Directional Solidification and Characterization of Hg(0.89) Mn(0.11)Te
NASA Technical Reports Server (NTRS)
Price, M. W.; Scripa, R. N.; Lehoczky. S. L.; Szofran, F. R.; Su, C.-H.
1998-01-01
Two boules of Hg(0.89)Mn(0.11)Te(MMT) were solidified using the vertical Bridgman-Stockbarger method. Translation rates of 0.09 and 0. 18 microns/s were used. The influence of growth rate on axial compositional homogeneity in the MMT boules was evaluated experimentally by conducting precision density measurements on radial slices taken from each boule. In addition, Plane Front Solidification theory and segregation coefficient (k) data for the Hg(1-x)Mn(x)Te system were used to fit theoretical composition profiles to the measured MMT axial composition profiles. The strong correlation between the measured and calculated MMT axial composition profiles indicates diffusion dominated axial solute redistribution in the boules under the applied growth conditions. The analysis of the MMT axial composition profiles by Plane Front Solidification theory allowed the calculation of the effective diffusion coefficient (D(eff) = 3.5 x l0(exp -5) sq cm/s). The k-values for the Hg(1-x)Mn(x)Te system and the D(sub eff) - value were then used to verify that both boules were solidified under conditions which did not exceed the Constitutional Supercooling Criteria under ideal conditions. Finally, a preliminary examination of the radial compositional variation in each MMT was made using Fourier Transform Infra-Red Spectroscopy (FTIR). The radial homogeneity in the MMT boules was found to be comparable for both translation rates.
Comprehensive chlorophyll composition in the main edible seaweeds.
Chen, Kewei; Ríos, José Julián; Pérez-Gálvez, Antonio; Roca, María
2017-08-01
Natural chlorophylls present in seaweeds have been studied regarding their biological activities and health benefit effects. However, detailed studies regarding characterization of the complete chlorophyll profile either qualitatively and quantitatively are scarce. This work deals with the comprehensive spectrometric study of the chlorophyll derivatives present in the five main coloured edible seaweeds. The novel complete MS 2 characterization of five chlorophyll derivatives: chlorophyll c 2 , chlorophyll c 1 , purpurin-18 a, pheophytin d and phytyl-purpurin-18 a has allowed to obtain fragmentation patterns associated with their different structural features. New chlorophyll derivatives have been identified and quantified by first time in red, green and brown seaweeds, including some oxidative structures. Quantitative data of the chlorophyll content comes to achieve significant information for food composition databases in bioactive compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.
Control of interface reactions in SIC/TI composites
NASA Technical Reports Server (NTRS)
Houska, C. R.; Rao, V.
1982-01-01
The reaction between a 0.5 to 1.0 Al film and a thick Ti substrate to form TiAl3 occurs very rapidly on heating to 635 C and causes the Al to be confined to the surface region. After heating to 900 C Ti3Al is formed with little release of Al into alpha Ti. Further annealing at 900 C eventually causes the Ti3Al phase to decompose and a substantial amount of Al is released into alpha Ti. The interdiffusion coefficient for Al in alpha Ti at 900 C increases by less than one order of magnitude as Al is varied from 0 to 20 at %. These data were obtained from the (101) X-ray diffraction intensity band using polycrystalline samples. Improvements in the analysis of X-ray diffraction data for the determination of composition profiles are discussed.
Tan, Q Y; Xu, M L; Wu, J Y; Yin, H F; Zhang, J Q
2012-04-01
A novel pyridostigmine bromide poly (lactic acid) nanoparticles (PBPNPs) was prepared to obtain sustained release characteristics of PB. A central composite design approach was employed for process optimization. The in vitro release studies were carried out by dialysis method and conducted using four different dissolution media. Similar factor method was investigated for dissolution profile comparison. Multiple linear regression analysis for process optimization revealed that the optimal PBPNPs were obtained where the values of the amount of PB (X1, mg), PLA concentration (X2, % w:v), and PVA concentration (X3, % w:v) were 49.20 mg, 3.31% and 3.41%, respectively. The average particle size and zeta potential of PBPNPs with the optimized formulation were 722.9 +/- 4.3 nm, and -25.12 +/- 1.2 mV, respectively. PBPNPs provided an initial burst of drug release followed by a very slow release over an extended period of time (72 h). Compared with free PB, PBPNPs had a significantly lower release rate of PB in vitro. The in vitro release profile of the PBPNPs could be described by Weibull models, regardless of type of dissolution medium. Statistical significance of similarity between every two dissolution profiles of PBPNPs in different dissolution media was found, and the difference between the curves of PBPNPs and pure PB was statistically significant.
TITAN’S UPPER ATMOSPHERE FROM CASSINI/UVIS SOLAR OCCULTATIONS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Capalbo, Fernando J.; Bénilan, Yves; Yelle, Roger V.
2015-12-01
Titan’s atmosphere is composed mainly of molecular nitrogen, methane being the principal trace gas. From the analysis of 8 solar occultations measured by the Extreme Ultraviolet channel of the Ultraviolet Imaging Spectrograph (UVIS) on board Cassini, we derived vertical profiles of N{sub 2} in the range 1100–1600 km and vertical profiles of CH{sub 4} in the range 850–1300 km. The correction of instrument effects and observational effects applied to the data are described. We present CH{sub 4} mole fractions, and average temperatures for the upper atmosphere obtained from the N{sub 2} profiles. The occultations correspond to different times and locations,more » and an analysis of variability of density and temperature is presented. The temperatures were analyzed as a function of geographical and temporal variables, without finding a clear correlation with any of them, although a trend of decreasing temperature toward the north pole was observed. The globally averaged temperature obtained is (150 ± 1) K. We compared our results from solar occultations with those derived from other UVIS observations, as well as studies performed with other instruments. The observational data we present confirm the atmospheric variability previously observed, add new information to the global picture of Titan’s upper atmosphere composition, variability, and dynamics, and provide new constraints to photochemical models.« less
Ntlhokwe, Gaalebalwe; Tredoux, Andreas G J; Górecki, Tadeusz; Edwards, Matthew; Vestner, Jochen; Muller, Magdalena; Erasmus, Lené; Joubert, Elizabeth; Christel Cronje, J; de Villiers, André
2017-07-01
The applicability of comprehensive two-dimensional gas chromatography (GC×GC) using a single-stage thermal modulator was explored for the analysis of honeybush tea (Cyclopia spp.) volatile compounds. Headspace solid phase micro-extraction (HS-SPME) was used in combination with GC×GC separation on a non-polar × polar column set with flame ionisation (FID) detection for the analysis of fermented Cyclopia maculata, Cyclopia subternata and Cyclopia genistoides tea infusions of a single harvest season. Method optimisation entailed evaluation of the effects of several experimental parameters on the performance of the modulator, the choice of columns in both dimensions, as well as the HS-SPME extraction fibre. Eighty-four volatile compounds were identified by co-injection of reference standards. Principal component analysis (PCA) showed clear differentiation between the species based on their volatile profiles. Due to the highly reproducible separations obtained using the single-stage thermal modulator, multivariate data analysis was simplified. The results demonstrate both the complexity of honeybush volatile profiles and the potential of GC×GC separation in combination with suitable data analysis techniques for the investigation of the relationship between sensory properties and volatile composition of these products. The developed method therefore offers a fast and inexpensive methodology for the profiling of honeybush tea volatiles. Graphical abstract Surface plot obtained for the GC×GC-FID analysis of honeybush tea volatiles.
Profiling defect depth in composite materials using thermal imaging NDE
NASA Astrophysics Data System (ADS)
Obeidat, Omar; Yu, Qiuye; Han, Xiaoyan
2018-04-01
Sonic Infrared (IR) NDE, is a relatively new NDE technology; it has been demonstrated as a reliable and sensitive method to detect defects. SIR uses ultrasonic excitation with IR imaging to detect defects and flaws in the structures being inspected. An IR camera captures infrared radiation from the target for a period of time covering the ultrasound pulse. This period of time may be much longer than the pulse depending on the defect depth and the thermal properties of the materials. With the increasing deployment of composites in modern aerospace and automobile structures, fast, wide-area and reliable NDE methods are necessary. Impact damage is one of the major concerns in modern composites. Damage can occur at a certain depth without any visual indication on the surface. Defect depth information can influence maintenance decisions. Depth profiling relies on the time delays in the captured image sequence. We'll present our work on the defect depth profiling by using the temporal information of IR images. An analytical model is introduced to describe heat diffusion from subsurface defects in composite materials. Depth profiling using peak time is introduced as well.
Santos, Iná S; Barros, Aluísio JD; Matijasevich, Alicia; Zanini, Roberta; Chrestani Cesar, Maria Aurora; Camargo-Figuera, Fabio Alberto; Oliveira, Isabel O; Barros, Fernando C; Victora, Cesar G
2014-01-01
This is an update of the 2004 Pelotas Birth Cohort profile, originally published in 2011. In view of the high prevalence of overweight and mental health problems among Brazilian children, together with the availability of state-of-the-art equipment to assess body composition and diagnostic tests for mental health in childhood, the main outcomes measured in the fifth follow-up (mean age 6.8 years) included child body composition, mental health and cognitive ability. A total of 3722 (90.2%) of the original mothers/carers were interviewed and their children examined in a clinic where they underwent whole-body dual X-ray absorptiometry (DXA), air displacement plethysmography and a 3D photonic scan. Saliva samples for DNA were obtained. Clinical psychologists applied the Development and Well-Being Assessment questionnaire and the Wechsler Intelligence Scale for Children to all children. Results are being compared with those of the two earlier cohorts to assess the health effects of economic growth and full implementation of public policies aimed at reducing social inequalities in the past 30 years. For further information visit the programme website at [http://www.epidemio-ufpel.org.br/site/content/coorte_2004/questionarios.php]. Applications to use the data should be made by contacting 2004 cohort researchers and filling in the application form available at [http://www.epidemio-ufpel.org.br/site/content/estudos/formularios.php]. PMID:25063002
Kidd, Haack S.; Garchow, H.; Odelson, D.A.; Forney, L.J.; Klug, M.J.
1994-01-01
We determined the accuracy and reproducibility of whole-community fatty acid methyl ester (FAME) analysis with two model bacterial communities differing in composition by using the Microbial ID, Inc. (MIDI), system. The biomass, taxonomic structure, and expected MIDI-FAME profiles under a variety of environmental conditions were known for these model communities a priori. Not all members of each community could be detected in the composite profile because of lack of fatty acid 'signatures' in some isolates or because of variations (approximately fivefold) in fatty acid yield across taxa. MIDI- FAME profiles of replicate subsamples of a given community were similar in terms of fatty acid yield per unit of community dry weight and relative proportions of specific fatty acids. Principal-components analysis (PCA) of MIDI-FAME profiles resulted in a clear separation of the two different communities and a clustering of replicates of each community from two separate experiments on the first PCA axis. The first PCA axis accounted for 57.1% of the variance in the data and was correlated with fatty acids that varied significantly between communities and reflected the underlying community taxonomic structure. On the basis of our data, community fatty acid profiles can be used to assess the relative similarities and differences of microbial communities that differ in taxonomic composition. However, detailed interpretation of community fatty acid profiles in terms of biomass or community taxonomic composition must be viewed with caution until our knowledge of the quantitative and qualitative distribution of fatty acids over a wide variety of taxa and the effects of growth conditions on fatty acid profiles is more extensive.
NASA Astrophysics Data System (ADS)
Dyroff, C.; Sanati, S.; Christner, E.; Zahn, A.; Balzer, M.; Bouquet, H.; McManus, J. B.; Gonzalez-Ramos, Y.; Schneider, M.
2015-05-01
Vertical profiles of water vapor (H2O) and its isotope ratio D / H expressed as δD(H2O) were measured in situ by the ISOWAT II diode-laser spectrometer during the MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA) airborne campaign. We present recent modifications of the instrument design. The instrument calibration on the ground as well as in flight is described. Based on the calibration measurements, the humidity-dependent uncertainty of our airborne data is determined. For the majority of the airborne data we achieved an accuracy (uncertainty of the mean) of Δ(δD) ≈10‰. Vertical profiles between 150 and ~7000 m were obtained during 7 days in July and August 2013 over the subtropical North Atlantic Ocean near Tenerife. The flights were coordinated with ground-based (Network for the Detection of Atmospheric Composition Change, NDACC) and space-based (Infrared Atmospheric Sounding Interferometer, IASI) FTIR remote sensing measurements of δD(H
2015-01-01
Metabolic profiling studies aim to achieve broad metabolome coverage in specific biological samples. However, wide metabolome coverage has proven difficult to achieve, mostly because of the diverse physicochemical properties of small molecules, obligating analysts to seek multiplatform and multimethod approaches. Challenges are even greater when it comes to applications to tissue samples, where tissue lysis and metabolite extraction can induce significant systematic variation in composition. We have developed a pipeline for obtaining the aqueous and organic compounds from diseased arterial tissue using two consecutive extractions, followed by a different untargeted UPLC-MS analysis method for each extract. Methods were rationally chosen and optimized to address the different physicochemical properties of each extract: hydrophilic interaction liquid chromatography (HILIC) for the aqueous extract and reversed-phase chromatography for the organic. This pipeline can be generic for tissue analysis as demonstrated by applications to different tissue types. The experimental setup and fast turnaround time of the two methods contributed toward obtaining highly reproducible features with exceptional chromatographic performance (CV % < 0.5%), making this pipeline suitable for metabolic profiling applications. We structurally assigned 226 metabolites from a range of chemical classes (e.g., carnitines, α-amino acids, purines, pyrimidines, phospholipids, sphingolipids, free fatty acids, and glycerolipids) which were mapped to their corresponding pathways, biological functions and known disease mechanisms. The combination of the two untargeted UPLC-MS methods showed high metabolite complementarity. We demonstrate the application of this pipeline to cardiovascular disease, where we show that the analyzed diseased groups (n = 120) of arterial tissue could be distinguished based on their metabolic profiles. PMID:25664760
Multicomponent Diffusion in Experimentally Cooled Melt Inclusions
NASA Astrophysics Data System (ADS)
Saper, L.; Stolper, E.
2017-12-01
Glassy olivine-hosted melt inclusions are compositionally zoned, characterized by a boundary layer depleted in olivine-compatible components that extends into the melt inclusion from its wall. The boundary layer forms in response to crystallization of olivine and relaxes with time due to diffusive exchange with the interior of the inclusion. At magmatic temperatures, the time scale for homogenization of inclusions is minutes to hours. Preservation of compositional gradients in natural inclusions results from rapid cooling upon eruption. A model of MgO concentration profiles that couples crystal growth and diffusive relaxation of a boundary layer can be used to solve for eruptive cooling rates [1]. Controlled cooling-rate experiments were conducted to test the accuracy of the model. Mauna Loa olivine containing >80 µm melt inclusions were equilibrated at 1225°C in a 1-atm furnace for 24 hours, followed by linear cooling at rates of 102 - 105 °C/hr. High-resolution concentration profiles of 40 inclusions were obtained using an electron microprobe. The model of [1] fits the experimental data with low residuals and the best-fit cooling rates are within 30% of experimental values. The initial temperature of 1225 °C is underestimated by 65°C. The model was modified using (i) MELTS to calculate the interface melt composition as a function of temperature, and (ii) a concentration-dependent MgO diffusion coefficient using the functional form of [2]. With this calibration the best-fit starting temperatures are within 5°C of the experimental values and the best-fit cooling rates are within 20% of experimental rates. The evolution of the CaO profile during cooling is evidence for strong diffusive coupling between melt components. Because CaO is incompatible in olivine, CaO concentrations are expected to be elevated in the boundary layer adjacent to the growing olivine. Although this is observed at short time scales, as the profile evolves the CaO concentration near the crystal interface becomes increasingly depleted. The drawdown in CaO can be explained by non-ideal mixing that leads to increases in the CaO activity coefficient in the melt. A regular solution model [3] can be used to describe the evolution of the CaO profiles. [1]Newcombe et al (2014) CMP 168 [2] Zhang (2010) RevMineralGeochem 72 [3] Ghiorso & Sack (1995) CMP 119
He, Ming-Jing; Lu, Jun-Feng; Ma, Jing-Ye; Wang, Huan; Du, Xiao-Fan
2018-06-01
Human hair and street dust from rural and urban areas in Chongqing were collected to analyze Organophosphate esters (OPEs) and phthalate esters (PAEs). Concentrations of OPEs in urban hair were significantly higher than those in rural hair, whereas PAEs concentrations in rural hair were significantly higher than those in urban hair. Different composition patterns of OPEs were observed in rural and urban hair, where tris (2-chloroisopropyl) phosphate (TCIPP), tris (butyl) phosphate (TNBP) and triphenyl phosphate (TPHP) were the dominating analogues in rural hair, accounting for 62.1% of the OPEs burden, and tris (methylphenyl) phosphate (TMPP) exhibited a high contribution in urban hair, responsible for 51.3% of total OPEs, which differed from the composition profiles in corresponding street dust. Analogous composition patterns of PAEs were found in hair of both areas. Di-(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DNBP), diisobutyl phthalate (DIBP) and diethyl phthalate (DEP) were the most abundant analogues in hair samples, while DEHP was the predominant analogue in dust samples. No clear tendency was obtained between the increasing ages and the concentrations of both compounds. Most OPEs and PAEs congeners showed significantly positive correlation with one another in rural hair. On the contrary, different correlation patterns were observed in urban hair for OPEs and PAEs, indicating multiple or additional sources existed in urban areas. Significant correlations of OPEs and PAEs were found between hair and corresponding street dust samples, but poor correlations of OPEs and PAEs were observed between rural hair and rural indoor dust, suggesting that street dust may be a predominant exogenous source for human exposure to OPEs and PAEs in this area. Copyright © 2018 Elsevier Ltd. All rights reserved.
Bayios, I A; Bergeles, N K; Apostolidis, N G; Noutsos, K S; Koskolou, M D
2006-06-01
The aims of the present study were: a) to determine the anthropometric profile, body composition and somatotype of elite Greek female basketball (B), volleyball (V) and handball (H) players, b) to compare the mean scores among sports and c) to detect possible differences in relation to competition level. A total of 518 female athletes, all members of the Greek first National League (A1 and A2 division) in B, V and H sport teams participated in the present study. Twelve anthropometric measures required for the calculation of body composition indexes and somatotype components were obtained according to the established literature. V athletes were the tallest (P<0.001) among the three groups of athletes, had the lowest values of body fat (P<0.001) and their somatotype was characterized as balanced endomorph (3.4-2.7-2.9). B athletes were taller (P<0.01) and leaner (P<0.001) than H players, with a somatotype characterized as mesomorph-endomorph (3.7-3.2-2.4). H athletes were the shortest of all (P<0.01), had the highest percentage of body fat (P<0.001) and their somatotype was mesomorph-endomorph (4.2-4.7-1.8). In comparison with their A2 counterparts the A1 division players were taller (P<0.001) and heavier (P<0.01), but at the same time leaner (P<0.001), and exhibited higher homogeneity in somatotype characteristics (P<0.05). Anthropometric, body composition and somatotype variables of Greek female elite teamball players varied among sports; selection criteria, hours of training and sport-specific physiological demands during the game could explain the observed differences. More data are certainly needed to define the anthropometric profile of B, V and H female athletes internationally.
Kien, C. Lawrence; Everingham, Karen I.; Stevens, Robert D.; Fukagawa, Naomi K.; Muoio, Deborah M.
2010-01-01
In cultured cells, palmitic acid (PA) and oleic acid (OA) confer distinct metabolic effects, yet, unclear, is whether changes in dietary fat intake impact cellular fatty acid (FA) composition. We hypothesized that short-term increases in dietary PA or OA would result in corresponding changes in the FA composition of skeletal muscle diacylglycerol (DAG) and triacylglycerol (TAG) and/or the specific FA selected for β-oxidation. Healthy males (N = 12) and females (N = 12) ingested a low-PA diet for 7 days. After fasting measurements of the serum acylcarnitine (AC) profile, subjects were randomized to either high-PA (HI PA) or low-PA/high-OA (HI OA) diets. After 7 days, the fasting AC measurement was repeated and a muscle/fat biopsy obtained. FA composition of intramyocellular DAG and TAG and serum AC was measured. HI PA increased, whereas HI OA decreased, serum concentration of 16:0 AC (P < 0.001). HI OA increased 18:1 AC (P = 0.005). HI PA was associated with a higher PA/OA ratio in muscle DAG and TAG (DAG: 1.03 ± 0.24 vs. 0.46 ± 0.08, P = 0.04; TAG: 0.63 ± 0.07 vs. 0.41 ± 0.03, P = 0.01). The PA concentration in the adipose tissue DAG (μg/mg adipose tissue) was 0.17 ± 0.02 in those receiving the HI PA diet (n = 6), compared to 0.11 ± 0.02 in the HI OA group (n = 4) (P = 0.067). The relative PA concentration in muscle DAG and TAG and the serum palmitoylcarnitine concentration was higher in those fed the high-PA diet. PMID:20559306
Kien, C Lawrence; Everingham, Karen I; D Stevens, Robert; Fukagawa, Naomi K; Muoio, Deborah M
2011-02-01
In cultured cells, palmitic acid (PA) and oleic acid (OA) confer distinct metabolic effects, yet, unclear, is whether changes in dietary fat intake impact cellular fatty acid (FA) composition. We hypothesized that short-term increases in dietary PA or OA would result in corresponding changes in the FA composition of skeletal muscle diacylglycerol (DAG) and triacylglycerol (TAG) and/or the specific FA selected for β-oxidation. Healthy males (N = 12) and females (N = 12) ingested a low-PA diet for 7 days. After fasting measurements of the serum acylcarnitine (AC) profile, subjects were randomized to either high-PA (HI PA) or low-PA/high-OA (HI OA) diets. After 7 days, the fasting AC measurement was repeated and a muscle/fat biopsy obtained. FA composition of intramyocellular DAG and TAG and serum AC was measured. HI PA increased, whereas HI OA decreased, serum concentration of 16:0 AC (P < 0.001). HI OA increased 18:1 AC (P = 0.005). HI PA was associated with a higher PA/OA ratio in muscle DAG and TAG (DAG: 1.03 ± 0.24 vs. 0.46 ± 0.08, P = 0.04; TAG: 0.63 ± 0.07 vs. 0.41 ± 0.03, P = 0.01). The PA concentration in the adipose tissue DAG (µg/mg adipose tissue) was 0.17 ± 0.02 in those receiving the HI PA diet (n = 6), compared to 0.11 ± 0.02 in the HI OA group (n = 4) (P = 0.067). The relative PA concentration in muscle DAG and TAG and the serum palmitoylcarnitine concentration was higher in those fed the high-PA diet.
Forero-Bogotá, Mónica Adriana; Ojeda-Pardo, Mónica Liliana; García-Hermoso, Antonio; Correa-Bautista, Jorge Enrique; González-Jiménez, Emilio; Schmidt-RíoValle, Jacqueline; Navarro-Pérez, Carmen Flores; Gracia-Marco, Luis; Vlachopoulos, Dimitris; Martínez-Torres, Javier; Ramírez-Vélez, Robinson
2017-01-01
The objective of the present study is to investigate the relationships between body composition, nutritional profile, muscular fitness (MF) and bone health in a sample of children and adolescents from Colombia. Participants included 1118 children and adolescents (54.6% girls). Calcaneal broadband ultrasound attenuation (c-BUA) was obtained as a marker of bone health. Body composition (fat mass and lean mass) was assessed using bioelectrical impedance analysis. Furthermore height, weight, waist circumference and Tanner stage were measured and body mass index (BMI) was calculated. Standing long-jump (SLJ) and isometric handgrip dynamometry were used respectively as indicators of lower and upper body muscular fitness. A muscular index score was also computed by summing up the standardised values of both SLJ and handgrip strength. Dietary intake and degree of adherence to the Mediterranean diet were assessed by a 7-day recall questionnaire for food frequency and the Kidmed questionnaire. Poor bone health was considered using a z-score cut off of ≤−1.5 standard deviation. Once the results were adjusted for age and Tanner stage, the predisposing factors of having a c-BUA z-score ≤−1.5 standard deviation included being underweight or obese, having an unhealthy lean mass, having an unhealthy fat mass, SLJ performance, handgrip performance, and unhealthy muscular index score. In conclusion, body composition (fat mass and lean body mass) and MF both influenced bone health in a sample of children and adolescents from Colombia. Thus promoting strength adaptation and preservation in Colombian youth will help to improve bone health, an important protective factor against osteoporosis in later life. PMID:28165360
Near-infrared luminescence of Bi2ZnOB2O6:Nd3+/PMMA composite
NASA Astrophysics Data System (ADS)
Jaroszewski, K.; Głuchowski, P.; Chrunik, M.; Jastrząb, R.; Majchrowski, A.; Kasprowicz, D.
2018-01-01
Near-infrared luminescence of a novel polymer composite system: PMMA doped with Bi2ZnOB2O6:Nd3+ microparticles, is reported for the first time. Luminescence properties of Bi2ZnOB2O6:Nd3+/PMMA were analyzed on the basis on excitation and emission spectra as well as fluorescence decay profiles. Excitation spectra monitored at 1062 nm (4F3/2 → 4I11/2) indicate numerous bands related to the optical transition of Nd3+ ions: from the 4I9/2 ground state to the 4D3/2, 2P1/2, 2K15/2, 4G7/2 + 4G9/2, 2K13/2, 4G5/2 + 2G7/2, 2H11/2, 4F9/2, 4F7/2 + 4S3/2, 4F5/2 + 2H9/2, 4F3/2 excited states. Many of them may be utilized to excite near-infrared emission of Nd3+ ions. In particular, distinctive Nd3+ emissions of the 4F3/2 → 4I9/2 and 4F3/2 → 4I11/2 transitions were detected, under excitation at 514 nm. The fluorescence decay profiles monitored at 1062 nm, excited at 514 nm, show relatively long emission lifetime of the 4F3/2 → 4I11/2 transition equal to 85 μs. Raman spectroscopy was used to determine vibrational properties and homogeneity of Bi2ZnOB2O6:Nd3+/PMMA composites. The obtained results suggest that Bi2ZnOB2O6:Nd3+/PMMA composite may be applied as an effective source of near-infrared emission in a new integrated optoelectronic devices.
Double-Vacuum-Bag Process for Making Resin-Matrix Composites
NASA Technical Reports Server (NTRS)
Bradford, Larry J.
2007-01-01
A double-vacuum-bag process has been devised as a superior alternative to a single-vacuum-bag process used heretofore in making laminated fiber-reinforced resin-matrix composite-material structural components. This process is applicable to broad classes of high-performance matrix resins including polyimides and phenolics that emit volatile compounds (solvents and volatile by-products of resin-curing chemical reactions) during processing. The superiority of the double-vacuum-bag process lies in enhanced management of the volatile compounds. Proper management of volatiles is necessary for making composite-material components of high quality: if not removed and otherwise properly managed, volatiles can accumulate in interior pockets as resins cure, thereby forming undesired voids in the finished products. The curing cycle for manufacturing a composite laminate containing a reactive resin matrix usually consists of a two-step ramp-and-hold temperature profile and an associated single-step pressure profile as shown in Figure 1. The lower-temperature ramp-and-hold step is known in the art as the B stage. During the B stage, prepregs are heated and volatiles are generated. Because pressure is not applied at this stage, volatiles are free to escape. Pressure is applied during the higher-temperature ramp-and-hold step to consolidate the laminate and impart desired physical properties to the resin matrix. The residual volatile content and fluidity of the resin at the beginning of application of consolidation pressure are determined by the temperature and time parameters of the B stage. Once the consolidation pressure is applied, residual volatiles are locked in. In order to produce a void-free, high-quality laminate, it is necessary to design the curing cycle to obtain the required residual fluidity and the required temperature at the time of application of the consolidation pressure.
NASA Astrophysics Data System (ADS)
Xia, Song; Wan, Linglin; Li, Aifen; Sang, Min; Zhang, Chengwu
2013-11-01
Algal biotechnology has advanced greatly in the past three decades. Many microalgae are now cultivated to produce bioactive substances. Odontella aurita is a marine diatom industrially cultured in outdoor open ponds and used for human nutrition. For the first time, we have systematically investigated the effects of culture conditions in cylindrical glass columns and flat-plate photobioreactors, including nutrients (nitrogen, phosphorus, silicon, and sulfur), light intensity and light path, on O. aurita cell growth and biochemical composition (protein, carbohydrate, β-1,3-glucan, lipids, and ash). The optimal medium for photoautotrophic cultivation of O. aurita contained 17.65 mmol/L nitrogen, 1.09 mmol/L phosphorus, 0.42 mmol/L silicon, and 24.51 mmol/L sulfur, yielding a maximum biomass production of 6.1-6.8 g/L and 6.7-7.8 g/L under low and high light, respectively. Scale-up experiments were conducted with flat-plate photobioreactors using different light-paths, indicating that a short light path was more suitable for biomass production of O. aurita. Analyses of biochemical composition showed that protein content decreased while carbohydrate (mainly composed of β-1,3-glucan) increased remarkably to about 50% of dry weight during the entire culture period. The highest lipid content (19.7% of dry weight) was obtained under 0.11 mmol/L silicon and high light conditions at harvest time. Fatty acid Profiles revealed that 80% were C14, C16, and C20, while arachidonic acid and eicosapentaenoic acid (EPA) accounted for 1.6%-5.6% and 9%-20% of total fatty acids, respectively. High biomass production and characteristic biochemical composition Profiles make O. aurita a promising microalga for the production of bioactive components, such as EPA and β-1,3-glucan.
Forero-Bogotá, Mónica Adriana; Ojeda-Pardo, Mónica Liliana; García-Hermoso, Antonio; Correa-Bautista, Jorge Enrique; González-Jiménez, Emilio; Schmidt-RíoValle, Jacqueline; Navarro-Pérez, Carmen Flores; Gracia-Marco, Luis; Vlachopoulos, Dimitris; Martínez-Torres, Javier; Ramírez-Vélez, Robinson
2017-02-03
The objective of the present study is to investigate the relationships between body composition, nutritional profile, muscular fitness (MF) and bone health in a sample of children and adolescents from Colombia. Participants included 1118 children and adolescents (54.6% girls). Calcaneal broadband ultrasound attenuation (c-BUA) was obtained as a marker of bone health. Body composition (fat mass and lean mass) was assessed using bioelectrical impedance analysis. Furthermore height, weight, waist circumference and Tanner stage were measured and body mass index (BMI) was calculated. Standing long-jump (SLJ) and isometric handgrip dynamometry were used respectively as indicators of lower and upper body muscular fitness. A muscular index score was also computed by summing up the standardised values of both SLJ and handgrip strength. Dietary intake and degree of adherence to the Mediterranean diet were assessed by a 7-day recall questionnaire for food frequency and the Kidmed questionnaire. Poor bone health was considered using a z -score cut off of ≤-1.5 standard deviation. Once the results were adjusted for age and Tanner stage, the predisposing factors of having a c-BUA z-score ≤-1.5 standard deviation included being underweight or obese, having an unhealthy lean mass, having an unhealthy fat mass, SLJ performance, handgrip performance, and unhealthy muscular index score. In conclusion, body composition (fat mass and lean body mass) and MF both influenced bone health in a sample of children and adolescents from Colombia. Thus promoting strength adaptation and preservation in Colombian youth will help to improve bone health, an important protective factor against osteoporosis in later life.
Sanz, M J; Loarce, Y; Fominaya, A; Vossen, J H; Ferrer, E
2013-01-01
Two of the domains most widely shared among R genes are the nucleotide binding site (NBS) and protein kinase (PK) domains. The present study describes and maps a number of new oat resistance gene analogues (RGAs) with two purposes in mind: (1) to identify genetic regions that contain R genes and (2) to determine whether RGAs can be used as molecular markers for qualitative loci and for QTLs affording resistance to Puccinia coronata. Such genes have been mapped in the diploid A. strigosa × A. wiestii (Asw map) and the hexaploid MN841801-1 × Noble-2 (MN map). Genomic and cDNA NBS-RGA probes from oat, barley and wheat were used to produce RFLPs and to obtain markers by motif-directed profiling based on the NBS (NBS profiling) and PK (PK profiling) domains. The efficiency of primers used in NBS/PK profiling to amplify RGA fragments was assessed by sequencing individual marker bands derived from genomic and cDNA fragments. The positions of 184 markers were identified in the Asw map, while those for 99 were identified in the MN map. Large numbers of NBS and PK profiling markers were found in clusters across different linkage groups, with the PK profiling markers more evenly distributed. The location of markers throughout the genetic maps and the composition of marker clusters indicate that NBS- and PK-based markers cover partly complementary regions of oat genomes. Markers of the different classes obtained were found associated with the two resistance loci, PcA and R-284B-2, mapped on Asw, and with five out of eight QTLs for partial resistance in the MN map. 53 RGA-RFLPs and 187 NBS/PK profiling markers were also mapped on the hexaploid map A. byzantina cv. Kanota × A. sativa cv. Ogle. Significant co-localization was seen between the RGA markers in the KO map and other markers closely linked to resistance loci, such as those for P. coronata and barley yellow dwarf virus (Bydv) that were previously mapped in other segregating populations.
Franco-de-Moraes, Ana Carolina; de Almeida-Pititto, Bianca; da Rocha Fernandes, Gabriel; Gomes, Everton Padilha; da Costa Pereira, Alexandre; Ferreira, Sandra Roberta G
2017-01-01
To describe the abundance of major phyla and some genera in the gut microbiota of individuals according to dietary habits and examine their associations with inflammatory markers, insulin resistance, and cardiovascular risk profile. A total of 268 non-diabetic individuals were stratified into groups of dietary types (strict vegetarians, lacto-ovo-vegetarians, and omnivores). The taxonomic composition and phylogenetic structure of the microbiota were obtained through the analysis of the 16S rRNA gene. Samples were clustered into operational taxonomic units at 97% similarity using GreenGenes 13.5 database. Clinical, biochemical, and circulating inflammatory markers were compared by ANOVA or Kruskal-Wallis test. The sample (54.2% women, mean age 49.5 years) was composed of 66 strict vegetarians, 102 lacto-ovo-vegetarians and 100 omnivores. Considering the entire sample, the greatest abundant phyla were Firmicutes (40.7 ± 15.9%) and Bacteroidetes (39.5 ± 19.9%), and no difference in abundances was found between individuals with normal and excess weight. Stratifying by dietary types, the proportion of Firmicutes was lower and of Bacteroidetes was higher in strict vegetarians when compared to lacto-ovo-vegetarians and omnivores. At the genus level, strict vegetarians had a higher Prevotella abundance and Prevotella/Bacteroides ratio than the other groups. They also had a lower proportion of Faecalibacterium than lacto-ovo-vegetarians, and both vegetarian groups had higher proportions than did omnivores. Succinivibrio and Halomonas from the Proteobacteria phylum were overrepresented in omnivores. The omnivorous group showed higher values of anthropometric data, insulin, HOMA-IR, and a worse lipid profile. Inflammatory markers exhibited a gradual and significant increase from the vegetarians and lacto-ovo-vegetarians to the omnivorous group. There are differences in gut microbiota composition of individuals with distinct dietary habits, who differ according to their inflammatory and metabolic profiles. Based on the findings relative to bacteria abundances and on their recognized actions in the metabolism, we suggest that exposure to animal foods may favor an intestinal environment which could trigger systemic inflammation and insulin resistance-dependent metabolic disorders.
Microbial community changes as a possible factor controlling carbon sequestration in subsoil
NASA Astrophysics Data System (ADS)
Strücker, Juliane; Jörgensen, Rainer Georg
2015-04-01
In order to gain more knowledge regarding the microbial community and their influence on carbon sequestration in subsoil two depth profiles with different soil organic carbon (SOC) concentrations were sampled. The SOC concentrations developed naturally due to deposition and erosion. This experiment offers the opportunity to investigate to which extend natural SOC availability or other subsoil specific conditions influence the composition and the functional diversity of the microbial community and in return if there is any evidence how the microbial community composition affects carbon sequestration under these conditions. Soil samples were taken at four different depths on two neighbouring arable sites; one Kolluvisol with high SOC concentrations (8-12 g/kg) throughout the profile and one Luvisol with low SOC concentrations (3-4 g/kg) below 30 cm depth. The multi substrate induced respiration (MSIR) method was used to identify shifts in the functional diversity of the microbial community along the depth profiles. Amino sugars Muramic Acid and Glucosamine were measured as indicators for bacterial and fungal residues and ergosterol was determined as marker for saprotrophic fungi. The results of the discriminant analysis of the respiration values obtained from the 17 substrates used in the MSIR show that the substrate use in subsoil is different from the substrate use in topsoil. The amino sugar analysis and the ratio of ergosterol to microbial biomass C indicate that the fungal dominance of the microbial community decreases with depth. The results from this study support previous findings, which also observed decreasing fungal dominance with depth. Furthermore the MSIR approach shows clearly that not only the composition of the microbial community but also their substrate use changes with depth. Thus, a different microbial community with altered substrate requirements could be an important reason for enhanced carbon sequestration in subsoil. The fact that the MSIR was also able to differentiate between the two sites proves the assumption that resources are an important factor controlling the functional diversity of the microbial community, as abiotic factors are very similar for the two profiles, but the sites show a different depth gradient for SOC.
Cremonesi, P; Conte, G; Severgnini, M; Turri, F; Monni, A; Capra, E; Rapetti, L; Colombini, S; Chessa, S; Battelli, G; Alves, S P; Mele, M; Castiglioni, B
2018-01-08
Fat supplementation plays an important role in defining milk fatty acids (FA) composition of ruminant products. The use of sources rich in linoleic and α-linolenic acid favors the accumulation of conjugated linoleic acids isomers, increasing the healthy properties of milk. Ruminal microbiota plays a pivotal role in defining milk FA composition, and its profile is affected by diet composition. The aim of this study was to investigate the responses of rumen FA production and microbial structure to hemp or linseed supplementation in diets of dairy goats. Ruminal microbiota composition was determined by 16S amplicon sequencing, whereas FA composition was obtained by gas-chromatography technique. In all, 18 pluriparous Alpine goats fed the same pre-treatment diet for 40±7 days were, then, arranged to three dietary treatments consisting of control, linseed and hemp seeds supplemented diets. Independently from sampling time and diets, bacterial community of ruminal fluid was dominated by Bacteroidetes (about 61.2%) and Firmicutes (24.2%) with a high abundance of Prevotellaceae (41.0%) and Veillonellaceae (9.4%) and a low presence of Ruminococcaceae (5.0%) and Lachnospiraceae (4.3%). Linseed supplementation affected ruminal bacteria population, with a significant reduction of biodiversity; in particular, relative abundance of Prevotella was reduced (-12.0%), whereas that of Succinivibrio and Fibrobacter was increased (+50.0% and +75.0%, respectively). No statistically significant differences were found among the average relative abundance of archaeal genera between each dietary group. Moreover, the addition of linseed and hemp seed induced significant changes in FA concentration in the rumen, as a consequence of shift from C18 : 2n-6 to C18 : 3n-3 biohydrogenation pathway. Furthermore, dimethylacetal composition was affected by fat supplementation, as consequence of ruminal bacteria population modification. Finally, the association study between the rumen FA profile and the bacterial microbiome revealed that Fibrobacteriaceae is the bacterial family showing the highest and significant correlation with FA involved in the biohydrogenation pathway of C18 : 3n-3.
Barrio, P A; Crespillo, M; Luque, J A; Aler, M; Baeza-Richer, C; Baldassarri, L; Carnevali, E; Coufalova, P; Flores, I; García, O; García, M A; González, R; Hernández, A; Inglés, V; Luque, G M; Mosquera-Miguel, A; Pedrosa, S; Pontes, M L; Porto, M J; Posada, Y; Ramella, M I; Ribeiro, T; Riego, E; Sala, A; Saragoni, V G; Serrano, A; Vannelli, S
2018-07-01
One of the main goals of the Spanish and Portuguese-Speaking Group of the International Society for Forensic Genetics (GHEP-ISFG) is to promote and contribute to the development and dissemination of scientific knowledge in the field of forensic genetics. Due to this fact, GHEP-ISFG holds different working commissions that are set up to develop activities in scientific aspects of general interest. One of them, the Mixture Commission of GHEP-ISFG, has organized annually, since 2009, a collaborative exercise on analysis and interpretation of autosomal short tandem repeat (STR) mixture profiles. Until now, six exercises have been organized. At the present edition (GHEP-MIX06), with 25 participant laboratories, the exercise main aim was to assess mixture profiles results by issuing a report, from the proposal of a complex mock case. One of the conclusions obtained from this exercise is the increasing tendency of participating laboratories to validate DNA mixture profiles analysis following international recommendations. However, the results have shown some differences among them regarding the edition and also the interpretation of mixture profiles. Besides, although the last revision of ISO/IEC 17025:2017 gives indications of how results should be reported, not all laboratories strictly follow their recommendations. Regarding the statistical aspect, all those laboratories that have performed statistical evaluation of the data have employed the likelihood ratio (LR) as a parameter to evaluate the statistical compatibility. However, LR values obtained show a wide range of variation. This fact could not be attributed to the software employed, since the vast majority of laboratories that performed LR calculation employed the same software (LRmixStudio). Thus, the final allelic composition of the edited mixture profile and the parameters employed in the software could explain this data dispersion. This highlights the need, for each laboratory, to define through internal validations its criteria for editing and interpreting mixtures, and to continuous train in software handling. Copyright © 2018 Elsevier B.V. All rights reserved.
Effect of aggregate graining compositions on skid resistance of Exposed Aggregate Concrete pavement
NASA Astrophysics Data System (ADS)
Wasilewska, Marta; Gardziejczyk, Wladysław; Gierasimiuk, Pawel
2018-05-01
The paper presents the evaluation of skid resistance of EAC (Exposed Aggregate Concrete) pavements which differ in aggregate graining compositions. The tests were carried out on concrete mixes with a maximum aggregate size of 8 mm. Three types of coarse aggregates were selected depending on their resistance to polishing which was determined on the basis of the PSV (Polished Stone Value). Basalt (PSV 48), gabbro (PSV 50) and trachybasalt (PSV 52) aggregates were chosen. For each type of aggregate three graining compositions were designed, which differed in the content of coarse aggregate > 4mm. Their content for each series was as follows: A - 38%, B - 50% and C - 68%. Evaluation of the skid resistance has been performed using the FAP (Friction After Polishing) test equipment also known as the Wehner/Schulze machine. Laboratory method enables to compare the skid resistance of different types of wearing course under specified conditions simulating polishing processes. In addition, macrotexture measurements were made on the surface of each specimen using the Elatexure laser profile. Analysis of variance showed that at significance level α = 0.05, aggregate graining compositions as well as the PSV have a significant influence on the obtained values of the friction coefficient μm of the tested EAC pavements. The highest values of the μm have been obtained for EAC with the lowest amount of coarse aggregates (compositions A). In these cases the resistance to polishing of the aggregate does not significantly affect the friction coefficients. This is related to the large areas of cement mortar between the exposed coarse grains. Based on the analysis of microscope images, it was observed that the coarse aggregates were not sufficiently exposed. It has been proved that PSV significantly affected the coefficient of friction in the case of compositions B and C. This is caused by large areas of exposed coarse aggregate. The best parameters were achieved for the EAC pavements with graining composition B and C and trachybasalt aggregate.
Normandin, E; Sénéchal, M; Prud'homme, D; Rabasa-Lhoret, R; Brochu, M
2015-01-01
The dynapenic (DYN)-obese phenotype is associated with an impaired metabolic profile. However, there is a lack of evidences regarding the effect of lifestyle interventions on the metabolic profile of individual with dynapenic phenotype. The objective was to investigate the impact of caloric restriction (CR) with or without resistance training (RT) on body composition, metabolic profile and muscle strength in DYN and non-dynapenic (NDYN) overweight and obese menopausal women. 109 obese menopausal women (age 57.9 ± 9.0 yrs; BMI 32.1 ± 4.6 kg/m2) were randomized to a 6-month CR intervention with or without a RT program. Participants were categorized as DYN or NDYN based on the lowest tertile of relative muscle strength in our cohort (< 4.86 kg/BMI). Body composition was measured by DXA, body fat distribution by CT scan, glucose homeostasis at fasting state and during an euglycemic-hyperinsulinemic clamp, fasting lipids, resting blood pressure, fasting inflammation markers and maximal muscle strength. No difference was observed between groups at baseline for body composition and the metabolic profile. Overall, a treatment effect was observed for all variables of body composition and some variables of the metabolic profile (fasting insulin, glucose disposal, triglyceride levels, triglycerides/HDL-Chol ratio and resting diastolic blood pressure) (P between 0.05 and 0.001). No Group X Treatment interaction was observed for variables of body composition and the metabolic profile. However, an interaction was observed for muscle strength; which significantly improved more in the CR+RT NDYN group (all P ≤ 0.05). In the present study, dynapenia was not associated with a worse metabolic profile at baseline in overweight and obese menopausal women. DYN and NDYN menopausal women showed similar cardiometabolic benefit from CR or CR+RT interventions. However, our results showed that the addition of RT to CR was more effective in improving maximal strength in DYN and NDYN obese menopausal women.
Detection of mechanically recovered chicken meat using capillary gel electrophoresis.
Day, L; Brown, H
2001-05-01
This study investigated the use of capillary gel electrophoresis (CGE) as a method for differentiating between raw mechanically recovered chicken meat (MRM) and hand deboned chicken breast meat (HDM). Twenty samples of MRM were obtained and twenty samples of HDM were prepared in the laboratory. They were extracted and analysed using Prosort™ SDS-protein analysis reagent. There were obvious differences in the relative peak areas within the profiles obtained which distinguished raw MRM from raw HDM; specifically, that of haemoglobin was higher in MRM. Using the peak area of haemoglobin and its ratio to other peaks, the technique was tested using composite MRM-HDM mixtures. The results suggest that it is possible to differentiate mixtures containing 7.5% MRM from that of 0% MRM using the CGE method.
Neutral Mass Spectrometry for Venus Atmosphere and Surface
NASA Technical Reports Server (NTRS)
Mahaffy, Paul
2005-01-01
The assignment is to make precise (better than 1 %) measurements of isotope ratios and accurate (5-10%) measurements of abundances of noble gas and to obtain vertical profiles of trace chemically active gases from above the clouds all the way down to the surface. Science measurement objectives are as follows: 1) Determine the composition of Venus atmosphere, including trace gas species and light stable isotopes; 2) Accurately measure noble-gas isotopic abundance in the atmosphere; 3) Provide descent, surface, and ascent meteorological data; 4) Measure zonal cloud-level winds over several Earth days; 5) Obtain near-IR descent images of the surface from 10-km altitude to the surface; 6) Accurately measure elemental abundances & mineralogy of a core from the surface; and 7) Evaluate the texture of surface materials to constrain weathering environment.
Staniszewska-Slezak, Emilia; Malek, Kamilla; Baranska, Malgorzata
2015-08-05
Raman spectroscopy and four excitation lines in the visible (Vis: 488, 532, 633 nm) and near infrared (NIR: 785 nm) were used for biochemical analysis of rat tissue homogenates, i.e. myocardium, brain, liver, lung, intestine, and kidney. The Vis Raman spectra are very similar for some organs (brain/intestines and kidney/liver) and dominated by heme signals when tissues of lung and myocardium were investigated (especially with 532 nm excitation). On the other hand, the NIR Raman spectra are specific for each tissue and more informative than the corresponding ones collected with the Vis excitations. The spectra analyzed without any special pre-processing clearly illustrate different chemical composition of each tissue and give information about main components e.g. lipids or proteins, but also about the content of some specific compounds such as amino acid residues, nucleotides and nucleobases. However, in order to obtain the whole spectral information about tissues complex composition the spectra of Vis and NIR excitations should be collected and analyzed together. A good agreement of data gathered from Raman spectra of the homogenates and those obtained previously from Raman imaging of the tissue cross-sections indicates that the presented here approach can be a method of choice for an investigation of biochemical variation in animal tissues. Moreover, the Raman spectral profile of tissue homogenates is specific enough to be used for an investigation of potential pathological changes the organism undergoes, in particular when supported by the complementary FTIR spectroscopy. Copyright © 2015 Elsevier B.V. All rights reserved.
Electrical conductivity of the Earth's mantle from the first Swarm magnetic field measurements
NASA Astrophysics Data System (ADS)
Civet, F.; Thébault, E.; Verhoeven, O.; Langlais, B.; Saturnino, D.
2015-05-01
We present a 1-D electrical conductivity profile of the Earth's mantle down to 2000 km derived from L1b Swarm satellite magnetic field measurements from November 2013 to September 2014. We first derive a model for the main magnetic field, correct the data for a lithospheric field model, and additionally select the data to reduce the contributions of the ionospheric field. We then model the primary and induced magnetospheric fields for periods between 2 and 256 days and perform a Bayesian inversion to obtain the probability density function for the electrical conductivity as function of depth. The conductivity increases by 3 orders of magnitude in the 400-900 km depth range. Assuming a pyrolitic mantle composition, this profile is interpreted in terms of temperature variations leading to a temperature gradient in the lower mantle that is close to adiabatic.
Observations of interstellar hydrogen and deuterium toward Alpha Centauri A
NASA Technical Reports Server (NTRS)
Landsman, W. B.; Henry, R. C.; Moos, H. W.; Linsky, J. L.
1984-01-01
A composite profile is presented of the Ly-alpha emission line of Alpha Cen A, obtained from 10 individual spectra with the high-resolution spectrograph aboard the International Ultraviolet Explorer (IUE) satellite. There is excellent overall agreement with two previous Copernicus observations. Interstellar deuterium is detected, and a lower limit is set on the deuterium to hydrogen ratio of nDI/nHI greater than 8 x 10 to the -6th. In addition, the deuterium bulk velocity appears blueshifted by 8 + or - 2 km/s with respect to interstellar hydrogen, suggesting a nonuniform medium along the line of sight.
Lopes, L S; Martins, S R; Chizzotti, M L; Busato, K C; Oliveira, I M; Machado Neto, O R; Paulino, P V R; Lanna, D P D; Ladeira, M M
2014-08-01
This study evaluated the effect of feed restriction and goat genotype on meat quality. Three genotypes (Brazilian native breed Canindé; Brazilian native breed Moxotó; and F1 Boer crossbred animals obtained by crossing Boer bucks with local breed does) and three different feeding regimens (ad libitum fed, AL; restricted fed at 75% of the ad libitum, R.75; or restricted fed at 50% of the average ad libitum intake, R.50) were used. There was no difference (P>0.05) in chemical composition, total and soluble collagen, and shear force of the Longissimus lumborum muscle among genotypes. However, AL had greater amounts of soluble collagen and crude protein in the muscle (P<0.05) than R.75. No difference (P>0.05) was observed for the myofibrillar fragmentation index. The goat genotype presented few differences in their fatty acid profiles. However, goats fed ad libitum had a more favorable fatty acid profile for human health with greater concentrations of oleic acid, unsaturated fatty acids, and conjugated linoleic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.
Synthesis and Comparison of Two cBN Composites with Starting Ternary Carbide Binders
NASA Astrophysics Data System (ADS)
Yue, Zhenming; Yang, Limin; Gong, Jianhong; Gao, Jun
2018-04-01
Ti3SiC2 and Ti3AlC2 are two promising binders for the ultrahard composite polycrystalline cubic boron nitride (PcBN). In this study, the cBN composites with Ti3SiC2 and Ti3AlC2 binders with different binder contents were synthesized under the same high pressure ( 5.5 GPa) and high temperature (1350 °C) conditions. Their mechanical properties were measured separately, including Vickers hardness, bending hardening, and compression hardening. Together with XRD results, the phase compounds were also investigated. The decomposition and reaction processes were affected by binder content. Some new compounds formed during sintering, these compounds were TiC, TiSi2, SiC, TiB2, SiB4, TiB2, and TiC0.7N0.3 in Ti3SiC2-cBN composites, as well as TiC0.7N0.3, TiB2, and AlN in Ti3AlC2-cBN composites. The microstructure of the cracks surface was obtained after the bending tests, and was used to further investigate and compare their crack mode by SEM. The crack surface profile and elementary analysis on the oxidative surface were also discussed.
Kahali Moghaddam, Maryam; Breede, Arne; Brauner, Christian; Lang, Walter
2015-01-01
The production of large and complex parts using fiber composite materials is costly due to the frequent formation of voids, porosity and waste products. By embedding different types of sensors and monitoring the process in real time, the amount of wastage can be significantly reduced. This work focuses on developing a knowledge-based method to improve and ensure complete impregnation of the fibers before initiation of the resin cure. Piezoresistive and capacitive pressure sensors were embedded in fiber composite laminates to measure the real-time the pressure values inside the laminate. A change of pressure indicates resin infusion. The sensors were placed in the laminate and the resin was infused by vacuum. The embedded piezoresistive pressure sensors were able to track the vacuum pressure in the fiber composite laminate setup, as well as the arrival of the resin at the sensor. The pressure increase due to closing the resin inlet was also measured. In contrast, the capacitive type of sensor was found to be inappropriate for measuring these quantities. The following study demonstrates real-time monitoring of pressure changes inside the fiber composite laminate, which validate the use of Darcy’s law in porous media to control the resin flow during infusion. PMID:25825973
Synthesis and Comparison of Two cBN Composites with Starting Ternary Carbide Binders
NASA Astrophysics Data System (ADS)
Yue, Zhenming; Yang, Limin; Gong, Jianhong; Gao, Jun
2018-05-01
Ti3SiC2 and Ti3AlC2 are two promising binders for the ultrahard composite polycrystalline cubic boron nitride (PcBN). In this study, the cBN composites with Ti3SiC2 and Ti3AlC2 binders with different binder contents were synthesized under the same high pressure ( 5.5 GPa) and high temperature (1350 °C) conditions. Their mechanical properties were measured separately, including Vickers hardness, bending hardening, and compression hardening. Together with XRD results, the phase compounds were also investigated. The decomposition and reaction processes were affected by binder content. Some new compounds formed during sintering, these compounds were TiC, TiSi2, SiC, TiB2, SiB4, TiB2, and TiC0.7N0.3 in Ti3SiC2-cBN composites, as well as TiC0.7N0.3, TiB2, and AlN in Ti3AlC2-cBN composites. The microstructure of the cracks surface was obtained after the bending tests, and was used to further investigate and compare their crack mode by SEM. The crack surface profile and elementary analysis on the oxidative surface were also discussed.
Kronewitter, Scott R; An, Hyun Joo; de Leoz, Maria Lorna; Lebrilla, Carlito B; Miyamoto, Suzanne; Leiserowitz, Gary S
2009-06-01
Annotation of the human serum N-linked glycome is a formidable challenge but is necessary for disease marker discovery. A new theoretical glycan library was constructed and proposed to provide all possible glycan compositions in serum. It was developed based on established glycobiology and retrosynthetic state-transition networks. We find that at least 331 compositions are possible in the serum N-linked glycome. By pairing the theoretical glycan mass library with a high mass accuracy and high-resolution MS, human serum glycans were effectively profiled. Correct isotopic envelope deconvolution to monoisotopic masses and the high mass accuracy instruments drastically reduced the amount of false composition assignments. The high throughput capacity enabled by this library permitted the rapid glycan profiling of large control populations. With the use of the library, a human serum glycan mass profile was developed from 46 healthy individuals. This paper presents a theoretical N-linked glycan mass library that was used for accurate high-throughput human serum glycan profiling. Rapid methods for evaluating a patient's glycome are instrumental for studying glycan-based markers.
Peluzio, M do C; de Miranda, L C; de Moraes, G H; Peluzio, L E
1998-12-01
The present work was conducted to obtain a proteic product and to evaluate its biological value in order to be used for human and/or domestic animal consumption. Thus, it were used cassava leaves as a non conventional source of protein. It was produced a freeze-dried, fat-free and colourless proteic isolated from those leaves (CLPI). This was mixed with casein and after the mixture as enzymatically hydrolyzed and resynthesized (Plastein reaction) to obtain a precipitated (PP) and a soluble plastein (SP) fractions. The protein contents observed were 64.39% (PS), 61.36% (PP) and 51.97% (CLPI). Trypsin inhibitor activities values showed a 41% reduction in the PP fraction suggesting that the heat treatment used to inactivated the enzyme also inactiveted partially the inhibitor or the reduction was due to the casein dilution. The amino acid composition of the frations obtained showed values close to the standards established. It can be concluded:--the utilization of non-conventional source should be stimulated when the proteins from those sources have an amino acidic profile that allow them to be used as an amino acid supplementation in food with low level of essential amino acids;--the fractions obtained by the plastein reaction showed satisfactory protein contents and their amino acid profiles were comparable with the FAO/OMS/UNU (1985) recommendations;--the plastein reaction can be utilized in food processing, after industrial scale adaptation remove compounds responsible to bitter taste, fetidness and to discolour protein products.
Luyssaert, Sebastiaan; Sulkava, Mika; Raitio, Hannu; Hollmén, Jaakko
2004-02-01
This paper introduces the use of nutrition profiles as a first step in the development of a concept that is suitable for evaluating forest nutrition on the basis of large-scale foliar surveys. Nutrition profiles of a tree or stand were defined as the nutrient status, which accounts for all element concentrations, contents and interactions between two or more elements. Therefore a nutrition profile overcomes the shortcomings associated with the commonly used concepts for evaluating forest nutrition. Nutrition profiles can be calculated by means of a neural network, i.e. a self-organizing map, and an agglomerative clustering algorithm with pruning. As an example, nutrition profiles were calculated to describe the temporal variation in the mineral composition of Scots pine and Norway spruce needles in Finland between 1987 and 2000. The temporal trends in the frequency distribution of the nutrition profiles of Scots pine indicated that, between 1987 and 2000, the N, S, P, K, Ca, Mg and Al decreased, whereas the needle mass (NM) increased or remained unchanged. As there were no temporal trends in the frequency distribution of the nutrition profiles of Norway spruce, the mineral composition of the needles of Norway spruce needles subsequently did not change. Interpretation of the (lack of) temporal trends was outside the scope of this example. However, nutrition profiles prove to be a new and better concept for the evaluation of the mineral composition of large-scale surveys only when a biological interpretation of the nutrition profiles can be provided.
Nutritional status and body composition in patients early after renal transplantation.
Netto, M C A S; Alves-Filho, G; Mazzali, M
2012-10-01
After renal transplantation recovery in nutritional status occurs during the first year. We assessed the changes in nutritional status after transplantation in 145 transplant recipients (94 males, 51 females). Patients were evaluated immediately after renal transplant (baseline data) and at 6 months' follow-up. Analysis included body mass index (BMI), body composition (skin fold and arm circumference), and estimated body composition (calculated percent of fat, arm circumference, arm muscle circumference, and arm muscle area). Other data obtained from medical records included renal function (MDRD) serum albumin and lipid profile. At baseline evaluation (21 ± 15 days posttransplant), mean BMI was 23.9 ± 3.9 kg/m(2), serum albumin was 3.7 ± 0.7 g/dL, and lipid profile showed (cholesterol 158.5 ± 52.7 mg% and triglycerides 135.9 ± 91.8 mg%. Body composition analysis showed better adaptation of muscle mass in females [AC (91 ± 10.2 × 98 ± 14.6; male × female, P < .05) arm muscle circumference (92.6 ± 1.4 × 102.3% ± 2.9%, male × female, P < .05) and arm muscle area (87.1 ± 22.3 × 105.5% ± 25.9%, male × female, P < .05)]. Body fat was above the recommended levels in 80% of patients, especially females. After 6 months we divided the groups according to BMI, observing better renal function in the normal weight group compared with obese subjects (60 ± 17.2 × 39.5 ± 19.8 mL/min MDRD, P < .05), despite comparable estimated glomerular filtration rate at baseline. The nutritional assessment of patients with end-stage renal disease early after renal transplantation, showed inadequate body composition, with increased fat and reduced lean body mass. The lower glomerular filtration rate after 6 months may be attributed to relatively inadequate renal mass or to obesity-induced hyperfiltration. Copyright © 2012 Elsevier Inc. All rights reserved.
Tu, Yiyou; Plotnikov, Elizaveta Y; Seidman, David N
2015-04-01
This study investigates the effects of the charge-state ratio of evaporated ions on the accuracy of local-electrode atom-probe (LEAP) tomographic compositional and structural analyses, which employs a picosecond ultraviolet pulsed laser. Experimental results demonstrate that the charge-state ratio is a better indicator of the best atom-probe tomography (APT) experimental conditions compared with laser pulse energy. The thermal tails in the mass spectra decrease significantly, and the mass resolving power (m/Δm) increases by 87.5 and 185.7% at full-width half-maximum and full-width tenth-maximum, respectively, as the laser pulse energy is increased from 5 to 30 pJ/pulse. The measured composition of this alloy depends on the charge-state ratio of the evaporated ions, and the most accurate composition is obtained when Ni2+/Ni+ is in the range of 0.3-20. The γ(f.c.c.)/γ'(L12) interface is quantitatively more diffuse when determined from the measured concentration profiles for higher laser pulse energies. Conclusions of the APT compositional and structural analyses utilizing the same suitable charge-state ratio are more comparable than those collected with the same laser pulse energy.
Kondou, Youichi; Manickavelu, Alagu; Komatsu, Kenji; Arifi, Mujiburahman; Kawashima, Mika; Ishii, Takayoshi; Hattori, Tomohiro; Iwata, Hiroyoshi; Tsujimoto, Hisashi; Ban, Tomohiro; Matsui, Minami
2016-01-01
This study was carried out with the aim of developing the methodology to determine elemental composition in wheat and identify the best germplasm for further research. Orphan and genetically diverse Afghan wheat landraces were chosen and EDXRF was used to measure the content of some of the elements to establish elemental composition in grains of 266 landraces using 10 reference lines. Four elements, K, Mg, P, and Fe, were measured by standardizing sample preparation. The results of hierarchical cluster analysis using elemental composition data sets indicated that the Fe content has an opposite pattern to the other elements, especially that of K. By systematic analysis the best wheat germplasms for P content and Fe content were identified. In order to compare the sensitivity of EDXRF, the ICP method was also used and the similar results obtained confirmed the EDXRF methodology. The sampling method for measurement using EDXRF was optimized resulting in high-throughput profiling of elemental composition in wheat grains at low cost. Using this method, we have characterized the Afghan wheat landraces and isolated the best genotypes that have high-elemental content and have the potential to be used in crop improvement. PMID:28163583
Composition Independent Thermometry in Gaseous Combustion Using Spectral Lineshape Information
NASA Astrophysics Data System (ADS)
Zelenak, Dominic
2016-11-01
Temperature is an important thermochemical property that holds the key to revealing several combustion phenomena such as pollutant formation, flame extinction, and heat release. In a practical combusting environment, the local composition is unknown, hindering the effectiveness of established non-intrusive thermometry techniques. This study aims to offset this limitation by developing laser thermometry techniques that do not require prior knowledge of the local composition. Multiple methods for obtaining temperature are demonstrated, which make use of the spectral line broadening of an absorbing species (Kr) seeded into the flow. These techniques involve extracting the Doppler broadening from the Voight profile and utilizing compositional scaling of collisional broadening and shift to determine temperature. Doppler broadening-temperature scaling of two photon Kr-PLIF is provided. Lean-premixed and diffusion jet flames of CH4 will serve as the test bed for experimentation, and validation of the two methods will be made using the corresponding temperature determined from Rayleigh scattering imaging with adiabatic mixing and unity Lewis number assumptions. A ratiometric dual lineshape thermometry method for turbulent flames will also be introduced. AFOSR Grant FA9550-16-1-0190 with Dr. Chiping Li as Program Manager.
NASA Astrophysics Data System (ADS)
Liang, Yabin; Li, Dongsheng; Parvasi, Seyed Mohammad; Kong, Qingzhao; Lim, Ing; Song, Gangbing
2016-09-01
Concrete-encased composite structure is a type of structure that takes the advantages of both steel and concrete materials, showing improved strength, ductility, and fire resistance compared to traditional reinforced concrete structures. The interface between concrete and steel profiles governs the interaction between these two materials under loading, however, debonding damage between these two materials may lead to severe degradation of the load transferring capacity which will affect the structural performance significantly. In this paper, the electro-mechanical impedance (EMI) technique using piezoceramic transducers was experimentally investigated to detect the bond-slip occurrence of the concrete-encased composite structure. The root-mean-square deviation is used to quantify the variations of the impedance signatures due to the presence of the bond-slip damage. In order to verify the validity of the proposed method, finite element model analysis was performed to simulate the behavior of concrete-steel debonding based on a 3D finite element concrete-steel bond model. The computed impedance signatures from the numerical results are compared with the results obtained from the experimental study, and both the numerical and experimental studies verify the proposed EMI method to detect bond slip of a concrete-encased composite structure.
Shape and Composition Map of a Prepyramid Quantum Dot
NASA Astrophysics Data System (ADS)
Spencer, Brian
2006-03-01
We present a theory for the shape, size, and nonuniform composition profile of a small prepyramid island in an alloy epitaxial film when surface diffusion is much faster than deposition and bulk diffusion. The predicted composition profile has segregation of the larger misfit component to the island peak, with segregation enhanced by misfit strain and solute strain but retarded by alloy solution thermodynamics. Vertical composition gradients through the center of the island due to this mechanism are on the order of 2%/nm for GeXSi1-X/Si and 10 - 15%/nm for InXGaAs1-X/GaAs [PRL 95, 206101 (2005)].
Ansah, John P; Malhotra, Rahul; Lew, Nicola; Chiu, Chi-Tsun; Chan, Angelique; Bayer, Steffen; Matchar, David B
2015-01-01
This study compares projections, up to year 2040, of young-old (aged 60-79) and old-old (aged 80+) with functional disability in Singapore with and without accounting for the changing educational composition of the Singaporean elderly. Two multi-state population models, with and without accounting for educational composition respectively, were developed, parameterized with age-gender-(education)-specific transition probabilities (between active, functional disability and death states) estimated from two waves (2009 and 2011) of a nationally representative survey of community-dwelling Singaporeans aged ≥ 60 years (N=4,990). Probabilistic sensitivity analysis with the bootstrap method was used to obtain the 95% confidence interval of the transition probabilities. Not accounting for educational composition overestimated the young-old with functional disability by 65 percent and underestimated the old-old by 20 percent in 2040. Accounting for educational composition, the proportion of old-old with functional disability increased from 40.8 percent in 2000 to 64.4 percent by 2040; not accounting for educational composition, the proportion in 2040 was 49.4 percent. Since the health profiles, and hence care needs, of the old-old differ from those of the young-old, health care service utilization and expenditure and the demand for formal and informal caregiving will be affected, impacting health and long-term care policy.
Ansah, John P.; Malhotra, Rahul; Lew, Nicola; Chiu, Chi-Tsun; Chan, Angelique; Bayer, Steffen; Matchar, David B.
2015-01-01
This study compares projections, up to year 2040, of young-old (aged 60-79) and old-old (aged 80+) with functional disability in Singapore with and without accounting for the changing educational composition of the Singaporean elderly. Two multi-state population models, with and without accounting for educational composition respectively, were developed, parameterized with age-gender-(education)-specific transition probabilities (between active, functional disability and death states) estimated from two waves (2009 and 2011) of a nationally representative survey of community-dwelling Singaporeans aged ≥60 years (N=4,990). Probabilistic sensitivity analysis with the bootstrap method was used to obtain the 95% confidence interval of the transition probabilities. Not accounting for educational composition overestimated the young-old with functional disability by 65 percent and underestimated the old-old by 20 percent in 2040. Accounting for educational composition, the proportion of old-old with functional disability increased from 40.8 percent in 2000 to 64.4 percent by 2040; not accounting for educational composition, the proportion in 2040 was 49.4 percent. Since the health profiles, and hence care needs, of the old-old differ from those of the young-old, health care service utilization and expenditure and the demand for formal and informal caregiving will be affected, impacting health and long-term care policy. PMID:25974069
Farinha, Inês; Freitas, Filomena; Reis, Maria A M
2017-07-25
The yeast Komagataella pastoris was cultivated under different fed-batch strategies for the production of chitin-glucan complex (CGC), a co-polymer of chitin and β-glucan. The tested fed-batch strategies included DO-stat mode, predefined feeding profile and repeated fed-batch operation. Although high cell dry mass and high CGC production were obtained under the tested DO-stat strategy in a 94h cultivation (159 and 29g/L, respectively), the overall biomass and CGC productivities were low (41 and 7.4g/Lday, respectively). Cultivation with a predefined profile significantly improved both biomass and CGC volumetric productivity (87 and 10.8g/Lday, respectively). Hence, this strategy was used to implement a repeated fed-batch process comprising 7 consecutive cycles. A daily production of 119-126g/L of biomass with a CGC content of 11-16wt% was obtained, thus proving this cultivation strategy is adequate to reach a high CGC productivity that ranged between 11 and 18g/Lday. The process was stable and reproducible in terms of CGC productivity and polymer composition, making it a promising strategy for further process development. Copyright © 2016 Elsevier B.V. All rights reserved.
Khammassi, Marwa; Ouerghi, Nejmeddine; Hadj-Taieb, Sameh; Feki, Moncef; Thivel, David; Bouassida, Anissa
2018-01-01
Although High-intensity interval training (HIIT) has shown its effectiveness in improving body composition, cardio-respiratory fitness and lipid profile in obese adults, evidences remain limited in overweight/obese youth. This study was conducted to investigate the effect of a 12-week HIIT program without caloric restriction on body composition and lipid profile among young overweight/obese men. Twenty healthy obese youth were randomly allocated into two groups; experimental group (HIIT) and control group. The HIIT program consisted in 3 exercises sessions per week (30 sec of work at 100% maximal aerobic velocity [MAV]) interspersed by 30 sec of active recovery at 50% MAV, starting by 15 repetitions to reach 27 by the end of the program. Aerobic capacity (MAV and maximum oxygen uptake [VO2max]), body composition (body mass index [BMI], waist circumference [WC], and fat mass percent) and lipid profile (triglycerides [TG] and total, high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol) were determined before and after the HIIT program. Following 12 weeks of HIIT, WC, BMI (P<0.01), and fat mass percent (P<0.05) were significantly decreased. MAV and VO2max were significantly improved in the HIIT group, only. Total cholesterol (P<0.05) and TG (P<0.05) decreased significantly in the HIIT group, while LDL and HDL cholesterol levels remained unchanged in both groups. HIIT may be particularly useful in overweight/obese youth to improve body composition, aerobic fitness and lipid profile. PMID:29511662
Khammassi, Marwa; Ouerghi, Nejmeddine; Hadj-Taieb, Sameh; Feki, Moncef; Thivel, David; Bouassida, Anissa
2018-02-01
Although High-intensity interval training (HIIT) has shown its effectiveness in improving body composition, cardio-respiratory fitness and lipid profile in obese adults, evidences remain limited in overweight/obese youth. This study was conducted to investigate the effect of a 12-week HIIT program without caloric restriction on body composition and lipid profile among young overweight/obese men. Twenty healthy obese youth were randomly allocated into two groups; experimental group (HIIT) and control group. The HIIT program consisted in 3 exercises sessions per week (30 sec of work at 100% maximal aerobic velocity [MAV]) interspersed by 30 sec of active recovery at 50% MAV, starting by 15 repetitions to reach 27 by the end of the program. Aerobic capacity (MAV and maximum oxygen uptake [VO2max]), body composition (body mass index [BMI], waist circumference [WC], and fat mass percent) and lipid profile (triglycerides [TG] and total, high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol) were determined before and after the HIIT program. Following 12 weeks of HIIT, WC, BMI ( P <0.01), and fat mass percent ( P <0.05) were significantly decreased. MAV and VO2max were significantly improved in the HIIT group, only. Total cholesterol ( P <0.05) and TG ( P <0.05) decreased significantly in the HIIT group, while LDL and HDL cholesterol levels remained unchanged in both groups. HIIT may be particularly useful in overweight/obese youth to improve body composition, aerobic fitness and lipid profile.
Seismic structure of the uppermost mantle beneath the Kenya rift
Keller, Gordon R.; Mechie, J.; Braile, L.W.; Mooney, W.D.; Prodehl, C.
1994-01-01
A major goal of the Kenya Rift International Seismic Project (KRISP) 1990 experiment was the determination of deep lithospheric structure. In the refraction/wide-angle reflection part of the KRISP effort, the experiment was designed to obtain arrivals to distances in excess of 400 km. Phases from interfaces within the mantle were recorded from many shotpoints, and by design, the best data were obtained along the axial profile. Reflected arrivals from two thin (< 10 km), high-velocity layers were observed along this profile and a refracted arrival was observed from the upper high-velocity layer. These mantle phases were observed on record sections from four axial profile shotpoints so overlapping and reversed coverage was obtained. Both high-velocity layers are deepest beneath Lake Turkana and become more shallow southward as the apex of the Kenya dome is approached. The first layer has a velocity of 8.05-8.15 km/s, is at a depth of about 45 km beneath Lake Turkana, and is observed at depths of about 40 km to the south before it disappears near the base of the crust. The deeper layer has velocities ranging from 7.7 to 7.8 km/s in the south to about 8.3 km/s in the north, has a similar dip as the upper one, and is found at depths of 60-65 km. Mantle arrivals outside the rift valley appear to correlate with this layer. The large amounts of extrusive volcanics associated with the rift suggest compositional anomalies as an explanation for the observed velocity structure. However, the effects of the large heat anomaly associated with the rift indicate that composition alone cannot explain the high-velocity layers observed. These layers require some anisotropy probably due to the preferred orientation of olivine crystals. The seismic model is consistent with hot mantle material rising beneath the Kenya dome in the southern Kenya rift and north-dipping shearing along the rift axis near the base of the lithosphere beneath the northern Kenya rift. This implies lithosphere thickening towards the north and is consistent with a thermal thinning of the lithosphere from below in the south changing to thinning of the lithosphere due to stretching in the north. ?? 1994.
Metagenomic Profiling of Microbial Composition and Antibiotic Resistance Determinants in Puget Sound
Port, Jesse A.; Wallace, James C.; Griffith, William C.; Faustman, Elaine M.
2012-01-01
Human-health relevant impacts on marine ecosystems are increasing on both spatial and temporal scales. Traditional indicators for environmental health monitoring and microbial risk assessment have relied primarily on single species analyses and have provided only limited spatial and temporal information. More high-throughput, broad-scale approaches to evaluate these impacts are therefore needed to provide a platform for informing public health. This study uses shotgun metagenomics to survey the taxonomic composition and antibiotic resistance determinant content of surface water bacterial communities in the Puget Sound estuary. Metagenomic DNA was collected at six sites in Puget Sound in addition to one wastewater treatment plant (WWTP) that discharges into the Sound and pyrosequenced. A total of ∼550 Mbp (1.4 million reads) were obtained, 22 Mbp of which could be assembled into contigs. While the taxonomic and resistance determinant profiles across the open Sound samples were similar, unique signatures were identified when comparing these profiles across the open Sound, a nearshore marina and WWTP effluent. The open Sound was dominated by α-Proteobacteria (in particular Rhodobacterales sp.), γ-Proteobacteria and Bacteroidetes while the marina and effluent had increased abundances of Actinobacteria, β-Proteobacteria and Firmicutes. There was a significant increase in the antibiotic resistance gene signal from the open Sound to marina to WWTP effluent, suggestive of a potential link to human impacts. Mobile genetic elements associated with environmental and pathogenic bacteria were also differentially abundant across the samples. This study is the first comparative metagenomic survey of Puget Sound and provides baseline data for further assessments of community composition and antibiotic resistance determinants in the environment using next generation sequencing technologies. In addition, these genomic signals of potential human impact can be used to guide initial public health monitoring as well as more targeted and functionally-based investigations. PMID:23144718
On mantle heterogeneity and anisotropy as mapped by inversion of global surface wave data
NASA Astrophysics Data System (ADS)
Khan, A.; Boschi, L.; Connolly, J.; Deschamps, F.
2008-12-01
We jointly invert Love and Rayleigh wave dispersion curves for the Earth's mantle composition, thermal state, P and S wave anisotropy at different locations on the Earth, based on self-consistent thermodynamic calculations. The method consists of four parts: 1. The composition of the Earth is modeled by the chemical system CaO-FeO-MgO- Al2O3-SiO2. Given these parameters and a geotherm (also an unknown), we calculate stable mineral modes, elastic properties, bulk density at the prevailing physical conditions using Gibbs free energy minimisation. Voigt-Reuss-Hill averaging is subsequently emplouyed to compute radial isotropic P and S wave velocity profiles in the elastic limit. 2. Anisotropic P and S wave velocities are determined from the isotropic ones by employing the relations ξ=(Vsh/Vsv)2, φ = (Vpv/Vph)2, η=F/(2A-L), Vs=(2Vsv2+Vsh2)/3 and Vp=(Vpv2+4Vph2)/5. The former three parameters are the standard anisotropy parameters, that we also invert for. 4. From these radial profiles, i.e. of Vsv, Vsh, Vph, Vpv and ρ, sunthetic Love and Rayleigh wave dispersion curves are calculated. The dispersion curves, which comprise fundamental and overtones up to 5th (Love) and 6th (Rayleigh) order have been extracted from global surface wave velocity maps. Given the above scheme, the data are at each location are jointly inverted using a Markov Chain Monte Carlo algorithm, from which a range of compositions, temperatures and radial profiles of anisotropy parameters, fitting data within uncertainties, are obtained. Our method has several advantages over standard approaches, in that no scaling relationships between Vs and Vp and ρ and Vs have to be introduced, implying that the full sensitivity of Rayleigh and Love waves to the parameters Vs, Vp and ρ is accounted for. In this particular study we investigate 5 locations distributed across the globe and reveal mantle chemical and thermal differences at these locations.
NASA Technical Reports Server (NTRS)
Long, E. R., Jr.
1979-01-01
The Bethe-Bloch stopping power relations for inelastic collisions were used to determine the absorption of electron and proton energy in cured neat epoxy resin and the absorption of electron energy in a graphite/epoxy composite. Absorption of electron energy due to bremsstrahlung was determined. Electron energies from 0.2 to 4.0 MeV and proton energies from 0.3 to 1.75 MeV were used. Monoenergetic electron energy absorption profiles for models of pure graphite, cured neat epoxy resin, and graphite/epoxy composites are reported. A relation is determined for depth of uniform energy absorption in a composite as a function of fiber volume fraction and initial electron energy. Monoenergetic proton energy absorption profiles are reported for the neat resin model. A relation for total proton penetration in the epoxy resin as a function of initial proton energy is determined. Electron energy absorption in the composite due to bremsstrahlung is reported. Electron and proton energy absorption profiles in cured neat epoxy resin are reported for environments approximating geosynchronous earth orbit.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ryerson, F J
The oxygen isotopic compositions of the world's oldest mineral grains, zircon, have recently been used to infer the compositions of the rocks from which they crystallized. The results appear to require a source that had once experienced isotopic fractionation between clay minerals and liquid water, thereby implying the presence of liquid water at the Earth's surface prior to 4.4 billion years ago, less than 2 million years after accretion. This observation has important implications for the development of the Earth's continental crust. The inferred composition of the zircon source rock is directly dependent upon the oxygen isotopic fractionation between zirconmore » and melt, and zircon and water. These fractionation factors have not been determined experimentally, however, constituting the weak link in this argument. A series of experiments to measure these fractionation factors has been conducted. The experiments consist of finely powdered quartz, a polished single crystal of zircon and isotopically-enriched or isotopically normal water to provide a range of isotopic compositions. The experiments will be run until quartz is in isotopic equilibrium with water. Zircon was expected to partially equilibrate producing an oxygen isotopic diffusion profile perpendicular to the surface. Ion probe spot analysis of quartz and depth profiling of zircon will determine the bulk and surface isotopic compositions of the phases, respectively. The well-known quartz-water isotopic fractionation factors can be used to calculate the oxygen isotopic composition of the fluid, and with the zircon surface composition, the zircon-water fractionation factor. Run at temperatures up to 1000 C for as long as 500 hours have not produced diffusion profiles longer than 50 nm. The steep isotopic gradient at the samples surface precludes use of the diffusion profile for estimation on the surface isotopic composition. The short profiles may be the result of surface dissolution, although such dissolution cannot be resolved in SEM images. The sluggish nature of diffusion in zircon may require that fractionation factors be determined by direct hydrothermal synthesis of zircon rather than by mineral-fluid exchange.« less
ERIC Educational Resources Information Center
Basgier, Christopher
2017-01-01
To illustrate how genre pedagogy and public writing pedagogy can inform one another, this program profile describes the second-semester composition course at University of North Dakota, ENGL 130: College Composition II: Writing for Public Audiences. In this course, genre works as a rhetorical bridge across an interlinked sequence of research,…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, W.S.; Mirdamadi, M.; Bakuckas, J.G. Jr.
1996-12-31
Titanium matrix composites (TMC), such as Ti-15V-3Cr-3Al-3Sn (Ti-15-3) reinforced with continuous silicon-carbide fibers (SCS-6), are being evaluated for use in hypersonic vehicles and advanced gas turbine engines where high strength-to-weight and high stiffness-to-weight ratios at elevated temperatures are critical. Such applications expose the composite to mechanical fatigue loading as well as thermally induced cycles. The damage accumulation behavior of a [0/90]2s laminate made of Ti-15V-3Cr-3Al-3Sn (Ti-15-3) reinforced with continuous silicon-carbide fibers (SCS-6) subjected to a simulated generic hypersonic flight profile, portions of the flight profile, and sustained loads was evaluated experimentally. Portions of the flight profile were used separately tomore » isolate combinations of load and time at temperature that influenced the fatigue behavior of the composite. Sustained load tests were also conducted and the results were compared with the fatigue results under the flight profile and its portions. The test results indicated that the fatigue strength of this materials system is considerably reduced by a combination of load and time at temperature.« less
Wang, Yan-Hong; Samoylenko, Volodymyr; Tekwani, Babu L; Khan, Ikhlas A; Miller, Loren S; Chaurasiya, Narayan D; Rahman, Md Mostafizur; Tripathi, Lalit M; Khan, Shabana I; Joshi, Vaishali C; Wigger, Frank T; Muhammad, Ilias
2010-04-21
Banisteriopsis caapi, a woody vine from the Amazonian basin, is popularly known as an ingredient of a sacred drink ayahuasca, widely used throughout the Amazon as a medicinal tea for healing and spiritual exploration. The usefulness of Banisteriopsis caapi has been established for alleviating symptoms of neurological disorders including Parkinson's disease. Primary objective of this study was to develop the process for preparing standardized extracts of Banisteriopsis caapi to achieve high potency for inhibition of human monoamine oxidases (MAO) and antioxidant properties. The aqueous extracts prepared from different parts of the plant collected from different geographical locations and seasons were analyzed by HPLC for principal bioactive markers. The extracts were simultaneously tested in vitro for inhibition of human MAOs and antioxidant activity for analysis of correlation between phytochemical composition of the extracts and bioactivities. Reversed-phase HPLC with photodiode array detection was employed to profile the alkaloidal and non-alkaloidal components of the aqueous extract of Banisteriopsis caapi. The Banisteriopsis caapi extracts and standardized compositions were tested in vitro for inhibition of recombinant preparations of human MAO-A and MAO-B. In vitro cell-based assays were employed for evaluation of antioxidant property and mammalian cell cytotoxicity of these preparations. Among the different aerial parts, leaves, stems/large branches and stem bark of Banisteriopsis caapi, HPLC analysis revealed that most of the dominant chemical and bioactive markers (1, 2, 5, 7-9) were present in high concentrations in dried bark of large branch. A library of HPLC chromatograms has also been generated as a tool for fingerprinting and authentication of the studied Banisteriopsis caapi species. The correlation between potency of MAO inhibition and antioxidant activity with the content of the main active constituents of the aqueous Banisteriopsis caapi extracts and standardized compositions was established. Phytochemical analysis of regular/commercial Banisteriopsis caapi dried stems, obtained from different sources, showed a similar qualitative HPLC profile, but relatively low content of dominant markers 1, 2, 7, and 9, which led to decreased MAO inhibitory and antioxidant potency compared to Banisteriopsis caapi Da Vine. The ethnopharmacological use of bark of matured stem/large branch of Banisteriopsis caapi as well as whole matured stem is supported by the results obtained in this investigation. Among various constituents of Banisteriopsis caapi, harmine (7), harmaline (6) and tetrahydroharmine (5) are responsible for MAO-A inhibition, while two major proanthocyanidines, epicatechin (8) and procyanidine B2 (9) produce antioxidant effects. The compounds 1-9 can serve as reliable markers for identification and standardization of Banisteriopsis caapi aerial parts, collected in different seasons and/or from different geographical regions. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.
Wang, Yan-Hong; Samoylenko, Volodymyr; Tekwani, Babu L.; Khan, Ikhlas A.; Miller, Loren S.; Chaurasiya, Narayan D.; Rahman, Md. Mostafizur; Tripathi, Lalit M.; Khan, Shabana I.; Joshi, Vaishali C.; Wigger, Frank T.; Muhammad, Ilias
2010-01-01
Ethnopharmacological relevance Banisteriopsis caapi, a woody vine from the Amazonian basin, is popularly known as an ingredient of a sacred drink ayahuasca, widely used throughout the Amazon as a medicinal tea for healing and spiritual exploration. The usefulness of B. caapi has been established for alleviating symptoms of neurological disorders including Parkinson’s disease. Aim of the study Primary objective of this study was to develop the process for preparing standardized extracts of B. caapi to achieve high potency for inhibition of human monoamine oxidases (MAO) and antioxidant properties. The aqueous extracts prepared from different parts of the plant collected from different geographical locations and seasons were analyzed by HPLC for principal bioactive markers. The extracts were simultaneously tested in vitro for inhibition of human MAOs and antioxidant activity for analysis of correlation between phytochemical composition of the extracts and bioactivities. Materials and methods Reversed-phase HPLC with photodiode array detection was employed to profile the alkaloidal and non-alkaloidal components of the aqueous extract of B. caapi. The B. caapi extracts and standardized compositions were tested in vitro for inhibition of recombinant preparations of human MAO-A and MAO-B. In vitro cell-based assays were employed for evaluation of antioxidant property and mammalian cell cytotoxicity of these preparations. Results Among the different aerial parts, leaves, stems/large branches and stem bark of B. caapi, HPLC analysis revealed that most of the dominant chemical and bioactive markers (1, 2, 5, 7-9) were present in high concentrations in dried bark of large branch. A library of HPLC chromatograms has also been generated as a tool for fingerprinting and authentication of the studied B. caapi species. The correlation between potency of MAO inhibition and antioxidant activity with the content of the main active constituents of the aqueous B. caapi extracts and standardized compositions was established. Phytochemical analysis of regular/ commercial B. caapi dried stems, obtained from different sources, showed a similar qualitative HPLC profile, but relatively low content of dominant markers 1, 2, 7, and 9, which led to decreased MAO inhibitory and antioxidant potency compared to B. caapi Da Vine. Conclusion The ethnopharmacological use of bark of matured stem/large branch of B. caapi as well as whole matured stem is supported by the results obtained in this investigation. Among various constituents of B. caapi, harmine (7), harmaline (6) and tetrahydroharmine (5) are responsible for MAO-A inhibition, while two major proanthocyanidines, epicatechin (8) and procyanidine B2 (9) produce antioxidant effects. The compounds 1-9 can serve as reliable markers for identification and standardization of B.caapi aerial parts, collected in different seasons and/or from different geographical regions. PMID:20219660
Composition profiling of seized ecstasy tablets by Raman spectroscopy.
Bell, S E; Burns, D T; Dennis, A C; Matchett, L J; Speers, J S
2000-10-01
Raman spectroscopy with far-red excitation has been investigated as a simple and rapid technique for composition profiling of seized ecstasy (MDMA, N-methyl-3,4-methylenedioxyamphetamine) tablets. The spectra obtained are rich in vibrational bands and allow the active drug and excipient used to bulk the tablets to be identified. Relative band heights can be used to determine drug/excipient ratios and the degree of hydration of the drug while the fact that 50 tablets per hour can be analysed allows large numbers of spectra to be recorded. The ability of Raman spectroscopy to distinguish between ecstasy tablets on the basis of their chemical composition is illustrated here by a sample set of 400 tablets taken from a large seizure of > 50,000 tablets that were found in eight large bags. The tablets are all similar in appearance and carry the same logo. Conventional analysis by GC-MS showed they contained MDMA. Initial Raman studies of samples from each of the eight bags showed that despite some tablet-to-tablet variation within each bag the contents could be classified on the basis of the excipients used. The tablets in five of the bags were sorbitol-based, two were cellulose-based and one bag contained tablets with a glucose excipient. More extensive analysis of 50 tablets from each of a representative series of sample bags have distribution profiles that showed the contents of each bag were approximately normally distributed about a mean value, rather than being mixtures of several discrete types. Two of the sorbitol-containing sample sets were indistinguishable while a third was similar but not identical to these, in that it contained the same excipient and MDMA with the same degree of hydration but had a slightly different MDMA/sorbitol ratio. The cellulose-based samples were badly manufactured and showed considerable tablet-to-tablet variation in their drug/excipient ratio while the glucose-based tablets had a tight distribution in their drug/excipient ratios. The degree of hydration in the MDMA feedstocks used to manufacture the cellulose-, glucose- and sorbitol-based tablets were all different from each other. This study, because it centres on a single seizure of physically similar tablets with the same active drug, highlights the fact that simple physical descriptions coupled with active drug content do not in themselves fully characterize the nature of the seized materials. There is considerable variation in the composition of the tablets within this single seizure and the fact that this variation can be detected from Raman spectra demonstrates that the potential benefits of obtaining highly detailed spectra can indeed translate into information that is not readily available from other methods but would be useful for tracing of drug distribution networks.
Stand-off molecular composition analysis
NASA Astrophysics Data System (ADS)
Hughes, Gary B.; Lubin, Philip; Meinhold, Peter; O'Neill, Hugh; Brashears, Travis; Zhang, Qicheng; Griswold, Janelle; Riley, Jordan; Motta, Caio
2015-09-01
Molecular composition of distant stars is explored by observing absorption spectra. The star produces blackbody radiation that passes through the molecular cloud of vaporized material surrounding the star. Characteristic absorption lines are discernible with a spectrometer, and molecular composition is investigated by comparing spectral observations with known material profiles. Most objects in the solar system—asteroids, comets, planets, moons—are too cold to be interrogated in this manner. Molecular clouds around cold objects consist primarily of volatiles, so bulk composition cannot be probed. Additionally, low volatile density does not produce discernible absorption lines in the faint signal generated by low blackbody temperatures. This paper describes a system for probing the molecular composition of cold solar system targets from a distant vantage. The concept utilizes a directed energy beam to melt and vaporize a spot on a distant target, such as from a spacecraft orbiting the object. With sufficient flux (~10 MW/m2), the spot temperature rises rapidly (to ~2 500 K), and evaporation of all materials on the target surface occurs. The melted spot creates a high-temperature blackbody source, and ejected material creates a molecular plume in front of the spot. Bulk composition is investigated by using a spectrometer to view the heated spot through the ejected material. Spatial composition maps could be created by scanning the surface. Applying the beam to a single spot continuously produces a borehole, and shallow sub-surface composition profiling is also possible. Initial simulations of absorption profiles with laser heating show great promise for molecular composition analysis.
Blaimer, Bonnie B.; Schmitt, Thomas
2017-01-01
Cuticular hydrocarbons (CHCs) cover the cuticles of virtually all insects, serving as a waterproofing agent and as a communication signal. The causes for the high CHC variation between species, and the factors influencing CHC profiles, are scarcely understood. Here, we compare CHC profiles of ant species from seven biogeographic regions, searching for physiological constraints and for climatic and biotic selection pressures. Molecule length constrained CHC composition: long-chain profiles contained fewer linear alkanes, but more hydrocarbons with disruptive features in the molecule. This is probably owing to selection on the physiology to build a semi-fluid cuticular layer, which is necessary for waterproofing and communication. CHC composition also depended on the precipitation in the ants' habitats. Species from wet climates had more alkenes and fewer dimethyl alkanes than those from drier habitats, which can be explained by different waterproofing capacities of these compounds. By contrast, temperature did not affect CHC composition. Mutualistically associated (parabiotic) species possessed profiles highly distinct from non-associated species. Our study is, to our knowledge, the first to show systematic impacts of physiological, climatic and biotic factors on quantitative CHC composition across a global, multi-species dataset. We demonstrate how they jointly shape CHC profiles, and advance our understanding of the evolution of this complex functional trait in insects. PMID:28298343
NASA Astrophysics Data System (ADS)
Hoseini-Athar, M. M.; Tolaminejad, B.
2016-07-01
Explosive welding is a well-known solid state method for joining similar and dissimilar materials. In the present study, tri-layered Al-Cu-Al laminated composites with different interface morphologies were fabricated by explosive welding and subsequent rolling. Effects of explosive ratio and rolling thickness reduction on the morphology of interface and mechanical properties were evaluated through optical/scanning electron microscopy, micro-hardness, tensile and tensile-shear tests. Results showed that by increasing the thickness reduction, bonding strength of specimens including straight and wavy interfaces increases. However, bonding strength of the specimens with melted layer interface decreases up to a threshold thickness reduction, then rapidly increases by raising the reduction. Hardness Values of welded specimens were higher than those of original material especially near the interface and a more uniform hardness profile was obtained after rolling process.
The Atmospheres of Pluto and Charon
NASA Astrophysics Data System (ADS)
Gladstone, R.; Summers, M. E.; Stern, A.; Ennico Smith, K.; Olkin, C.; Weaver, H. A., Jr.; Young, L. A.; Strobel, D. F.; Hinson, D. P.; Kammer, J.; Parker, A. H.; Steffl, A.; Linscott, I.; Parker, J. W.; Cheng, A. F.; Versteeg, M. H.; Greathouse, T.; Retherford, K. D.; Throop, H.; Woods, W. W.; Singer, K. N.; Tsang, C.; Schindhelm, E.; Wong, M. L.; Yung, Y. L.; Zhu, X.; Curdt, W.; Lavvas, P.; Young, E. F.; Tyler, G. L.
2015-12-01
Major goals of the New Horizons (NH) mission are to explore and characterize the structure and composition of Pluto's atmosphere, and to determine whether Charon has a measurable atmosphere of its own. Several instruments onboard NH contribute to these goals, primarily: 1) the REX instrument, through uplink X-band radio occultations, 2) the Alice instrument, through extreme- and far-ultraviolet solar occultations, and 3) the LORRI panchromatic imager, through high-phase-angle imaging. The associated datasets were obtained following closest approach of NH to Pluto. Pressure and temperature profiles of the lower atmosphere are derived from the REX data, the composition and structure of the extended atmosphere are derived from the Alice data (supported by approach observations of reflected ultraviolet sunlight), and the distribution and properties of Pluto's hazes are derived from the LORRI data. In this talk an overview of the early atmosphere science results will be presented.
Analysis of fresco by laser induced breakdown spectroscopy
NASA Astrophysics Data System (ADS)
Caneve, L.; Diamanti, A.; Grimaldi, F.; Palleschi, G.; Spizzichino, V.; Valentini, F.
2010-08-01
The laser-based techniques have been shown to be a very powerful tool for artworks characterization and are used in the field of cultural heritage for the offered advantages of minimum invasiveness, in situ applicability and high sensitivity. Laser induced breakdown spectroscopy, in particular, has been applied in this field to many different kinds of ancient materials with successful results. In this work, a fragment of a Roman wall painting from the archaeological area of Pompeii has been investigated by LIBS. The sample elemental composition resulting from LIBS measurements suggested the presence of certain pigments. The ratio of the intensities of different lines related to some characteristic elements is proposed as an indicator for pigment recognition. The depth profiling permitted to put in evidence the presence of successive paint layers with different compositions. A comparison with the results obtained by the microscopy inspection of the sample has been done.
Defect structure in electrodeposited nanocrystalline Ni layers with different Mo concentrations
NASA Astrophysics Data System (ADS)
Kapoor, Garima; Péter, László; Fekete, Éva; Gubicza, Jenő
2018-05-01
The effect of molybdenum (Mo) alloying on the lattice defect structure in electrodeposited nanocrystalline nickel (Ni) films was studied. The electrodeposited layers were prepared on copper substrate at room temperature, with a constant current density and pH value. The chemical composition of these layers was determined by EDS. In addition, X-ray diffraction line profile analysis was carried out to study the microstructural parameters such as the crystallite size, the dislocation density and the stacking fault probability. It was found that the higher Mo content yielded more than one order of magnitude larger dislocation density while the crystallite size was only slightly smaller. In addition, the twin boundary formation activity during deposition increased with increasing Mo concentration. The results obtained on electrodeposited layers were compared with previous research carried out on bulk nanocrystalline Ni-Mo materials with similar compositions but processed by severe plastic deformation.
NASA Astrophysics Data System (ADS)
Goffin, S.; Parent, F.; Plain, C.; Maier, M.; Schack-Kirchner, H.; Aubinet, M.; Longdoz, B.
2012-12-01
The overall aim of this study is to contribute to a better understanding of mechanisms behind soil CO2 efflux using carbon stable isotopes. The approach combines a soil multilayer analysis and the isotopic tool in an in situ study. The specific goal of this work is to quantify the origin and the determinism of 13CO2 and 12CO2 production processes in the different soil layers using the gradient-efflux approach. To meet this, the work includes an experimental setup and a modeling approach. The experimental set up (see also communication of Parent et al., session B008) comprised a combination of different systems, which were installed in a Scot Pine temperate forest at the Hartheim site (Southwestern Germany). Measurements include (i) half hourly vertical profiles of soil CO2 concentration (using soil CO2 probes), soil water content and temperature; (ii) half hourly soil surface CO2 effluxes (automatic chambers); (iii) half hourly isotopic composition of surface CO2 efflux and soil CO2 concentration profile and (iv) estimation of soil diffusivity through laboratory measurements conducted on soil samples taken at several depths. Using the data collected in the experimental part, we developed and used a diffusive transport model to simulate CO2 (13CO2 and 12CO2) flows inside and out of the soil based on Fick's first law. Given the horizontal homogeneity of soil physical parameters in Hartheim, we treated the soil as a structure consisting of distinctive layers of 5 cm thick and expressed the Fick's first law in a discrete formalism. The diffusion coefficient used in each layer was derived from (i) horizon specific relationships, obtained from laboratory measurements, between soil relative diffusivity and its water content and (ii) the soil water content values measured in situ. The concentration profile was obtained from in situ measurements. So, the main model inputs are the profiles of (i) CO2 (13CO2 and 12CO2) concentration, (ii) soil diffusion coefficient and (iii) soil water content. Once the diffusive fluxes deduced at each layer interface, the CO2 (13CO2 and 12CO2) production profile was calculated using the (discretized) mass balance equation in each layer. The results of the Hartheim measurement campaign will be presented. The CO2 source vertical profile and its link with the root and the Carbon organic content distribution will be showed. The dynamic of CO2 sources and their isotopic signature will be linked to climatic variables such soil temperature and soil water content. For example, we will show that the dynamics of CO2 sources was mainly related to temperature while changing of isotopic signature was more correlated to soil moisture.
NASA Astrophysics Data System (ADS)
Esteban Bedoya-Velásquez, Andrés; Navas-Guzmán, Francisco; José Granados-Muñoz, María; Titos, Gloria; Román, Roberto; Andrés Casquero-Vera, Juan; Ortiz-Amezcua, Pablo; Benavent-Oltra, Jose Antonio; de Arruda Moreira, Gregori; Montilla-Rosero, Elena; Hoyos, Carlos David; Artiñano, Begoña; Coz, Esther; José Olmo-Reyes, Francisco; Alados-Arboledas, Lucas; Guerrero-Rascado, Juan Luis
2018-05-01
This study focuses on the analysis of aerosol hygroscopic growth during the Sierra Nevada Lidar AerOsol Profiling Experiment (SLOPE I) campaign by using the synergy of active and passive remote sensors at the ACTRIS Granada station and in situ instrumentation at a mountain station (Sierra Nevada, SNS). To this end, a methodology based on simultaneous measurements of aerosol profiles from an EARLINET multi-wavelength Raman lidar (RL) and relative humidity (RH) profiles obtained from a multi-instrumental approach is used. This approach is based on the combination of calibrated water vapor mixing ratio (r) profiles from RL and continuous temperature profiles from a microwave radiometer (MWR) for obtaining RH profiles with a reasonable vertical and temporal resolution. This methodology is validated against the traditional one that uses RH from co-located radiosounding (RS) measurements, obtaining differences in the hygroscopic growth parameter (γ) lower than 5 % between the methodology based on RS and the one presented here. Additionally, during the SLOPE I campaign the remote sensing methodology used for aerosol hygroscopic growth studies has been checked against Mie calculations of aerosol hygroscopic growth using in situ measurements of particle number size distribution and submicron chemical composition measured at SNS. The hygroscopic case observed during SLOPE I showed an increase in the particle backscatter coefficient at 355 and 532 nm with relative humidity (RH ranged between 78 and 98 %), but also a decrease in the backscatter-related Ångström exponent (AE) and particle linear depolarization ratio (PLDR), indicating that the particles became larger and more spherical due to hygroscopic processes. Vertical and horizontal wind analysis is performed by means of a co-located Doppler lidar system, in order to evaluate the horizontal and vertical dynamics of the air masses. Finally, the Hänel parameterization is applied to experimental data for both stations, and we found good agreement on γ measured with remote sensing (γ532 = 0.48 ± 0.01 and γ355 = 0.40 ± 0.01) with respect to the values calculated using Mie theory (γ532 = 0.53 ± 0.02 and γ355 = 0.45 ± 0.02), with relative differences between measurements and simulations lower than 9 % at 532 nm and 11 % at 355 nm.
Fessenden, S W; Hackmann, T J; Ross, D A; Foskolos, A; Van Amburgh, M E
2017-09-01
Microbial samples from 4 independent experiments in lactating dairy cattle were obtained and analyzed for nutrient composition, AA digestibility, and AA profile after multiple hydrolysis times ranging from 2 to 168 h. Similar bacterial and protozoal isolation techniques were used for all isolations. Omasal bacteria and protozoa samples were analyzed for AA digestibility using a new in vitro technique. Multiple time point hydrolysis and least squares nonlinear regression were used to determine the AA content of omasal bacteria and protozoa, and equivalency comparisons were made against single time point hydrolysis. Formalin was used in 1 experiment, which negatively affected AA digestibility and likely limited the complete release of AA during acid hydrolysis. The mean AA digestibility was 87.8 and 81.6% for non-formalin-treated bacteria and protozoa, respectively. Preservation of microbe samples in formalin likely decreased recovery of several individual AA. Results from the multiple time point hydrolysis indicated that Ile, Val, and Met hydrolyzed at a slower rate compared with other essential AA. Singe time point hydrolysis was found to be nonequivalent to multiple time point hydrolysis when considering biologically important changes in estimated microbial AA profiles. Several AA, including Met, Ile, and Val, were underpredicted using AA determination after a single 24-h hydrolysis. Models for predicting postruminal supply of AA might need to consider potential bias present in postruminal AA flow literature when AA determinations are performed after single time point hydrolysis and when using formalin as a preservative for microbial samples. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Gastric microbial community profiling reveals a dysbiotic cancer-associated microbiota
Pereira-Marques, Joana; Pinto-Ribeiro, Ines; Costa, Jose L; Carneiro, Fatima; Machado, Jose C
2018-01-01
Objective Gastric carcinoma development is triggered by Helicobacter pylori. Chronic H. pylori infection leads to reduced acid secretion, which may allow the growth of a different gastric bacterial community. This change in the microbiome may increase aggression to the gastric mucosa and contribute to malignancy. Our aim was to evaluate the composition of the gastric microbiota in chronic gastritis and in gastric carcinoma. Design The gastric microbiota was retrospectively investigated in 54 patients with gastric carcinoma and 81 patients with chronic gastritis by 16S rRNA gene profiling, using next-generation sequencing. Differences in microbial composition of the two patient groups were assessed using linear discriminant analysis effect size. Associations between the most relevant taxa and clinical diagnosis were validated by real-time quantitative PCR. Predictive functional profiling of microbial communities was obtained with PICRUSt. Results The gastric carcinoma microbiota was characterised by reduced microbial diversity, by decreased abundance of Helicobacter and by the enrichment of other bacterial genera, mostly represented by intestinal commensals. The combination of these taxa into a microbial dysbiosis index revealed that dysbiosis has excellent capacity to discriminate between gastritis and gastric carcinoma. Analysis of the functional features of the microbiota was compatible with the presence of a nitrosating microbial community in carcinoma. The major observations were confirmed in validation cohorts from different geographic origins. Conclusions Detailed analysis of the gastric microbiota revealed for the first time that patients with gastric carcinoma exhibit a dysbiotic microbial community with genotoxic potential, which is distinct from that of patients with chronic gastritis. PMID:29102920
Xiao, Enzong; Krumins, Valdis; Tang, Song; Xiao, Tangfu; Ning, Zengping; Lan, Xiaolong; Sun, Weimin
2016-08-01
Mining activities have introduced various pollutants to surrounding aquatic and terrestrial environments, causing adverse impacts to the environment. Indigenous microbial communities are responsible for the biogeochemical cycling of pollutants in diverse environments, indicating the potential for bioremediation of such pollutants. Antimony (Sb) has been extensively mined in China and Sb contamination in mining areas has been frequently encountered. To date, however, the microbial composition and structure in response to Sb contamination has remained overlooked. Sb and As frequently co-occur in sulfide-rich ores, and co-contamination of Sb and As is observed in some mining areas. We characterized, for the first time, the microbial community profiles and their responses to Sb and As pollution from a watershed heavily contaminated by Sb tailing pond in Southwest China. The indigenous microbial communities were profiled by high-throughput sequencing from 16 sediment samples (535,390 valid reads). The comprehensive geochemical data (specifically, physical-chemical properties and different Sb and As extraction fractions) were obtained from river water and sediments at different depths as well. Canonical correspondence analysis (CCA) demonstrated that a suite of in situ geochemical and physical factors significantly structured the overall microbial community compositions. Further, we found significant correlations between individual phylotypes (bacterial genera) and the geochemical fractions of Sb and As by Spearman rank correlation. A number of taxonomic groups were positively correlated with the Sb and As extractable fractions and various Sb and As species in sediment, suggesting potential roles of these phylotypes in Sb biogeochemical cycling. Copyright © 2016 Elsevier Ltd. All rights reserved.
Adewoye, E O; Ige, A O
2016-01-01
Diabetes mellitus affects lipid levels resulting in diabetic dyslipidemia as well as electrolyte loss from the body. Musa sapientum has been reported to possess antidiabetic properties. This study assessed the lipid profile and electrolyte composition in alloxan-induced diabetic rats treated with methanol leaf extract of M. sapientum (cMEMSL). Diabetes was induced with alloxan (120 mg/kg i.p.). Seventy-five male albino rats were divided into 5 groups of 15 rats each. Group 1 was control; groups 2-5 were made diabetic and treated with 0.2 ml 0.9% NaCl, cMEMSL (250 mg/kg and 500 mg/kg), and glibenclamide (5 mg/kg), respectively, for 14 days. Blood samples were obtained from the retro orbital sinus after light anesthesia from 5 animals in each group on days 2, 7, and 14 for lipids and electrolyte analysis. Lipid profile of diabetic treated (cMEMSL and glibenclamide) animals showed significant reduction (p < .05) in total cholesterol, triglyceride, and low density lipoprotein (LDL) levels. The high density lipoprotein (HDL) level in the treatment groups increased significantly (p < .05) compared with diabetic untreated. Sodium, potassium, and phosphate ions significantly increased in all diabetic treatment groups while chloride ion significantly decreased compared with diabetic untreated. There was no significant difference in calcium and bicarbonate ion concentration in all the groups. This study has showed additional properties of Musa sapientum to include its ability to restore electrolyte balance, reduce cholesterol, triglyceride, LDL, and increase the HDL levels in diabetic animals.
Huygens GCMS Results from Titan
NASA Technical Reports Server (NTRS)
Niemann, Hasso B.; Demick, Jaime; Kasprzak, Wayne; Atreya, Sushil; Owen, Tobias
2007-01-01
The Huygens Probe executed a successful entry, descent and impact on the Saturnian moon of Titan on January 14, 2005. The Gas Chromatograph Mass Spectrometer (GCMS) instrument conducted isotopic and compositional measurements throughout the two and one half hour descent from 146 km altitude, and on the surface for 69 minutes until loss of signal from the orbiting Cassini spacecraft. The GCMS incorporated a quadrupole mass filter with a secondary electron multiplier detection system. The gas sampling system provided continuous direct atmospheric composition measurements and batch sampling through three gas chromatographic (GC) columns, a chemical scrubber and a hydrocarbon enrichment cell. The GCMS gas inlet was heated to prevent condensation, and to evaporate volatiles from the surface after impact. Data products from the GCMS included altitude profiles of the major atmospheric constituents dinitrogen (N2) and methane (CH4), isotope ratios of 14N/15N, 12C/13C, and D/H, mole fractions of radiogenic argon (40Ar) and primordial argon (36Ar), and upper limits on the mole fractions of neon, krypton and xenon, which were found to be absent. Surface measurements confirmed the presence of ethane (C2H6) and cyanogen (C2N2). Later data products expanded atmospheric profiles to include the surface response of C2N2. C2H6, acetylene (C2H2), and carbon dioxide (CO2). More recent results include the profiles of benzene (C6H6) and molecular hydrogen (H2). The GCMS data are being further analyzed to obtain higher precision results and to identify other trace species ion the atmosphere and evaporating from the surface.
Ahmed, I; Parsons, A J; Palmer, G; Knowles, J C; Walker, G S; Rudd, C D
2008-09-01
Composites comprising a biodegradable polymeric matrix and a bioactive filler show considerable promise in the field of regenerative medicine, and could potentially serve as degradable bone fracture fixation devices, depending on the properties obtained. Therefore, glass fibres from a binary calcium phosphate (50P(2)O(5)+50CaO) glass were used to reinforce polycaprolactone, at two different volume fractions (V(f)). As-drawn, non-treated and heat-treated fibres were assessed. Weight loss, ion release and the initial mechanical properties of the fibres and composites produced have been investigated. Single fibre tensile testing revealed a fibre strength of 474MPa and a tensile modulus of 44GPa. Weibull analysis suggested a scale value of 524. The composites yielded flexural strength and modulus of up to 30MPa and 2.5GPa, respectively. These values are comparable with human trabecular bone. An 8% mass loss was seen for the lower V(f) composite, whereas for the two higher V(f) composites an approximate 20% mass loss was observed over the course of the 5week study. A plateau in the degradation profile at 350h indicated that fibre dissolution was complete at this interval. This assertion was further supported via ion release studies. The leaching of fibres from the composite created a porous structure, including continuous channels within the polymer matrix. This offers further scope for tailoring scaffold development, as cells from the surrounding tissue may be induced to migrate into the resulting porous matrix.
A framework to spatially cluster air pollution monitoring sites in US based on the PM2.5 composition
Austin, Elena; Coull, Brent A.; Zanobetti, Antonella; Koutrakis, Petros
2013-01-01
Background Heterogeneity in the response to PM2.5 is hypothesized to be related to differences in particle composition across monitoring sites which reflect differences in source types as well as climatic and topographic conditions impacting different geographic locations. Identifying spatial patterns in particle composition is a multivariate problem that requires novel methodologies. Objectives Use cluster analysis methods to identify spatial patterns in PM2.5 composition. Verify that the resulting clusters are distinct and informative. Methods 109 monitoring sites with 75% reported speciation data during the period 2003–2008 were selected. These sites were categorized based on their average PM2.5 composition over the study period using k-means cluster analysis. The obtained clusters were validated and characterized based on their physico-chemical characteristics, geographic locations, emissions profiles, population density and proximity to major emission sources. Results Overall 31 clusters were identified. These include 21 clusters with 2 or more sites which were further grouped into 4 main types using hierarchical clustering. The resulting groupings are chemically meaningful and represent broad differences in emissions. The remaining clusters, encompassing single sites, were characterized based on their particle composition and geographic location. Conclusions The framework presented here provides a novel tool which can be used to identify and further classify sites based on their PM2.5 composition. The solution presented is fairly robust and yielded groupings that were meaningful in the context of air-pollution research. PMID:23850585
Cappucci, Alice; Alves, Susana P; Bessa, Rui J B; Buccioni, Arianna; Mannelli, Federica; Pauselli, Mariano; Viti, Carlo; Pastorelli, Roberta; Roscini, Valentina; Serra, Andrea; Conte, Giuseppe; Mele, Marcello
2018-06-01
Agro-industrial by-products contain several secondary plant metabolites, such as polyphenols, tannins, saponins, and essential oils. The effects of these compounds on animal metabolism may vary significantly according to the dose, the chemical nature of the molecules, and the overall composition of the diet. In the Mediterranean area, the olive oil extraction is associated with 2 by-products: olive pomace and wastewater, both rich in polyphenols. In particular, wastewater may be further processed to obtain olive crude phenolic concentrate (OCPC). An experiment was carried out aiming to evaluate animal performance, milk fatty acid (FA) profile, diversity of rumen microbial population, and rumen liquor FA profile in dairy ewes fed diets containing extruded linseed (EL) and increasing doses of OCPC. Twenty-eight Comisana ewes in mid lactation were allotted to 4 experimental groups. The experiment lasted 5 wk after 3 wk of adaptation. Diets were characterized by lucerne hay administrated ad libitum and by 800 g/ewe and day of 4 experimental concentrates containing 22% of EL on dry matter and increasing dose of OCPC: 0 (L0), 0.6 (L0.6), 0.8 (L0.8), and 1.2 (L1.2) g of OCPC/kg of dry matter. Milk yield was daily recorded and milk composition was analyzed weekly. At the beginning and at the end of the experiment, samples of rumen liquor were collected to analyze FA profile, changes in rumen microbial population, and dimethylacetal (DMA) composition. The inclusion of OCPC did not affect milk yield and gross composition, whereas milk from L0.8 and L1.2 sheep contained higher concentrations of linoleic (+18%) and α-linolenic acid (+24%) and lower concentration of the rumen biohydrogenation intermediates. A similar pattern was observed for rumen liquor FA composition. No differences were found in the diversity of the rumen microbial population. Total amount of DMA did not differ among treatments, whereas significant differences were found in the concentration of individual DMA; in the diet with a higher amount of OCPC, DMA 13:0, 14:0, 15:0, and 18:0 increased, whereas DMA 16:0 decreased. Probably the presence of polyphenols in the diet induced a rearrangement of bacteria membrane phospholipids as a response to the rumen environment stimulus. Overall, the use of OCPC allowed a significant increase in the polyunsaturated FA content of milk, probably due to a perturbation of the rumen biohydrogenation process. Further studies are needed to understand the correlation between diet composition and the pattern of DMA in rumen liquor. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Fry, John C; Webster, Gordon; Cragg, Barry A; Weightman, Andrew J; Parkes, R John
2006-10-01
The aim of this work was to relate depth profiles of prokaryotic community composition with geochemical processes in the deep subseafloor biosphere at two shallow-water sites on the Peru Margin in the Pacific Ocean (ODP Leg 201, sites 1228 and 1229). Principal component analysis of denaturing gradient gel electrophoresis banding patterns of deep-sediment Bacteria, Archaea, Euryarchaeota and the novel candidate division JS1, followed by multiple regression, showed strong relationships with prokaryotic activity and geochemistry (R(2)=55-100%). Further correlation analysis, at one site, between the principal components from the community composition profiles for Bacteria and 12 other variables quantitatively confirmed their relationship with activity and geochemistry, which had previously only been implied. Comparison with previously published cell counts enumerated by fluorescent in situ hybridization with rRNA-targeted probes confirmed that these denaturing gradient gel electrophoresis profiles described an active prokaryotic community.
Gohel, M C; Patel, M M; Amin, A F
2003-05-01
This article reports the preparation of tartaric acid treated ispaghula husk powder for the development of modified release tablets of diltiazem HCl by adopting direct compression technique and a 32 full factorial design. The modified ispaghula husk powder showed superior swelling and gelling as compared to untreated powder. Addition of compaction augmenting agent such as dicalcium phosphate was found to be essential for obtaining tablets with adequate crushing strength. In order to improve the crushing strength of diltiazem HCl tablets, to modulate drug release pattern, and to obtain similarity of dissolution profiles in distilled water and simulated gastric fluid (pH 1.2), modified guar gum was used along with modified ispaghula husk powder and tartaric acid. A novel composite index, which considers a positive or a negative deviation from an ideal value, was calculated considering percentage drug release in 60, 300, and 540 min as dependent variables for the selection of a most appropriate batch. Polynomial equation and contour plots are presented. The concept of similarity factor (f2) was used to prove similarity of dissolution in water and simulated gastric fluid (pH 1.2).
Chemical composition and functional characterisation of commercial pumpkin seed oil.
Procida, Giuseppe; Stancher, Bruno; Cateni, Francesca; Zacchigna, Marina
2013-03-30
Pumpkin (Cucurbita pepo L.) seed oil is a common product in Slovenia, Hungary and Austria and is considered a preventive agent for various pathologies, particularly prostate diseases. These properties are related to its high content of carotenoids and liposoluble vitamins. In this study the carotenoid (lutein and zeaxanthin), vitamin E (α- and γ-tocopherol) and fatty acid contents of 12 samples of commercial pumpkin seed oil were investigated together with the composition of the volatile fraction resulting from the roasting process. The aromatic profile obtained from the commercial samples was directly related to the intensity of the roasting process of the crushed pumpkin seeds. The roasting temperature played a crucial role in the concentrations of volatile substances originating from Strecker degradation, lipid peroxidation and Maillard reaction. The findings suggest that high-temperature roasting leads to the production of an oil with intense aromatic characteristics, while mild conditions, generally employed to obtain an oil with professed therapeutic characteristics, lead to a product with minor characteristic pumpkin seed oil aroma. The nutraceutical properties of the product are confirmed by the high content of α- and γ-tocopherol and carotenoids. © 2012 Society of Chemical Industry.
Chawla, Raj; Sharma, Sumit
2018-03-18
Styrene-butadiene rubber is a copolymer widely used in making car tires and has excellent abrasion resistance. The Young's modulus and tribology of pure styrene butadiene rubber (SBR) polymer and carbon nanotube reinforced polymer composites have been investigated using molecular dynamics simulations. The mechanism of enhanced tribology properties using carbon nanotube has been studied and discussed. The obtained Young's modulus shows the enhancement in mechanical properties of SBR polymer when carbon nanotubes are used as reinforcement. The concentration, temperature and velocity profiles, radial distribution function, frictional stresses, and cohesive energy density are calculated and analyzed in detail. The Young's modulus of SBR matrix increases about 29.16% in the presence of the 5% CNT. The atom movement velocity and average cohesive energy density in the friction area of pure SBR matrix was found to be more than that of the CNT/SBR composite. Graphical abstract Initial and final conditions of (a) pure SBR matrix and (b) CNT/SBR matrix subjected toshear loading and frictional stresses of top Fe layers of both pure SBR and CNT/SBR composite.
Miranda, Andrea Lobo; Costa, Samantha Serra; Assis, Denilson de Jesus; Andrade, Bianca Bomfim; de Souza, Carolina Oliveira; Oliveira, Maria Beatriz Prior Pinto; Guimarães, Alaíse Gil; Druzian, Janice Izabel
2018-07-15
In this study, we investigated the cellular fatty acid profiles of different Xanthomonas pathovars producing xanthan gum and explored the fatty acid composition to identify chemical markers of xanthan gum productivity and quality. Three Xanthomonas pathovars were studied. The fermentation was conducted for 168 h. Samples from the fermented medium were collected for extraction, quantification, and characterization of xanthan. The unsaturated/saturated (U/S) fatty acid ratio in Xanthomonas cells during fermentation was correlated with production, viscosity, and molecular weight of the gum obtained at each 24 h. The Xanthomonas axonopodis pv manihotis 290 strain showed a higher U/S ratio for major cell fatty acids (C16:1ω7/C16:0) as compared with the other two strains; this high ratio was directly associated with xanthan production. No correlation was observed between cellular fatty acid composition and characteristics of xanthan synthesized. Thus, it was possible to determine a production chemical marker for xanthan gum in Xanthomonas strains. Copyright © 2018 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Varley, J. B.; Conway, A. M.; Voss, L. F.
Thallium bromide (TlBr) crystals subjected to hydrochloric acid (HCl) chemical treatments have been shown to advantageously affect device performance and longevity in TlBr-based room temperature radiation detectors, yet the exact mechanisms of the improvements remain poorly understood. Here in this paper, we investigate the influence of several HCl chemical treatments on device-grade TlBr and describe the changes in the composition and electronic structure of the surface. Composition analysis and depth profiles obtained from secondary ion mass spectrometry (SIMS) identify the extent to which each HCl etch condition affects the detector surface region and forms of a graded TlBr/TlBr 1-xCL xmore » surface heterojunction. Using a combination of X-ray photoemission spectroscopy (XPS) and hybrid density functional calculations, we are able to determine the valence band offsets, band gaps, and conduction band offsets as a function of Cl content over the entire composition range of TIBr 1-xC1 X. This study establishes a strong correlation between device process conditions, surface chemistry, and electronic structure with the goal of further optimizing the long-term stability and radiation response of TlBr-based detectors.« less
NASA Astrophysics Data System (ADS)
Munch, Federico; Grayver, Alexander; Khan, Amir; Kuvshinov, Alexey
2017-04-01
As most of Earth's interior remains geochemically unsampled, geophysical techniques based on seismology, geodesy, gravimetry, and electromagnetic studies play prominent roles because of their ability to sense structure at depth. Although seismic tomography maps show a variety of structures, separating thermal and compositional contributions from seismic velocities alone still remains a challenging task. Alternatively, as electrical conductivity is sensitive to temperature, chemical composition, oxygen fugacity, water content, and the presence of melt, it can serve for determining chemistry, mineralogy, and physical structure of the deep mantle. In this work we estimate and invert local C-responses (period range 3-100 days) for a number of worldwide geomagnetic observatories to map lateral variations of electrical conductivity in Earth's mantle (400-1600 km depth). The obtained conductivity profiles are interpreted in terms of basalt fraction in a basalt-harzburgite mixture, temperature structure, and water content variations. Interpretation is based on a self-consistent thermodynamic calculation of mineral phase equilibria, electrical conductivity databases, and probabilistic inverse methods.
Liu, Xiaoling; Grant, David M; Parsons, Andrew J; Harper, Lee T; Rudd, Chris D; Ahmed, Ifty
2013-01-01
Bioresorbable phosphate glass fibre reinforced polyester composites have been investigated as replacement for some traditional metallic orthopaedic implants, such as bone fracture fixation plates. However, composites tested revealed loss of the interfacial integrity after immersion within aqueous media which resulted in rapid loss of mechanical properties. Physical modification of fibres to change fibre surface morphology has been shown to be an effective method to improve fibre and matrix adhesion in composites. In this study, biodegradable magnesium which would gradually degrade to Mg(2+) in the human body was deposited via magnetron sputtering onto bioresorbable phosphate glass fibres to obtain roughened fibre surfaces. Fibre surface morphology after coating was observed using scanning electron microscope (SEM). The roughness profile and crystalline texture of the coatings were determined via atomic force microscope (AFM) and X-ray diffraction (XRD) analysis, respectively. The roughness of the coatings was seen to increase from 40 ± 1 nm to 80 ± 1 nm. The mechanical properties (tensile strength and modulus) of fibre with coatings decreased with increased magnesium coating thickness.
Liu, Xiaoling; Grant, David M.; Parsons, Andrew J.; Harper, Lee T.; Rudd, Chris D.; Ahmed, Ifty
2013-01-01
Bioresorbable phosphate glass fibre reinforced polyester composites have been investigated as replacement for some traditional metallic orthopaedic implants, such as bone fracture fixation plates. However, composites tested revealed loss of the interfacial integrity after immersion within aqueous media which resulted in rapid loss of mechanical properties. Physical modification of fibres to change fibre surface morphology has been shown to be an effective method to improve fibre and matrix adhesion in composites. In this study, biodegradable magnesium which would gradually degrade to Mg2+ in the human body was deposited via magnetron sputtering onto bioresorbable phosphate glass fibres to obtain roughened fibre surfaces. Fibre surface morphology after coating was observed using scanning electron microscope (SEM). The roughness profile and crystalline texture of the coatings were determined via atomic force microscope (AFM) and X-ray diffraction (XRD) analysis, respectively. The roughness of the coatings was seen to increase from 40 ± 1 nm to 80 ± 1 nm. The mechanical properties (tensile strength and modulus) of fibre with coatings decreased with increased magnesium coating thickness. PMID:24066297
Raman measurement of carotenoid composition in human skin
NASA Astrophysics Data System (ADS)
Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner
2004-07-01
The carotenoids lycopene and beta-carotene are powerful antioxidants in skin and are thought to act as scavengers for free radicals and singlet oxygen. The role of carotenoid species in skin health is of strong current interest. We demonstrate the possibility to use Resonance Raman spectroscopy for fast, non-invasive, highly specific, and quantitative detection of beta-carotene and lycopene in human skin. Analyzing Raman signals originating from the carbon-carbon double bond stretch vibrations of the carotenoid molecules under blue and green laser excitation, we were able to characterize quantitatively the relative concentrations of each carotenoid species in-vivo. In the selective detection, we take advantage of different Raman cross-section spectral profiles for beta-carotene and lycopene molecules, and obtain a quantitative assessment of individual long-chain carotenoid species in the skin rather than their cumulative levels. Preliminary dual-wavelength Raman measurements reveal significant differences in the carotenoid composition of different subjects. The technique holds promise for rapid screening of carotenoid compositions in human skin in large populations and may be suitable in clinical studies for assessing the risk for cutaneous diseases.
Waligórski, M P R; Grzanka, L; Korcyl, M; Olko, P
2015-09-01
An algorithm was developed of a treatment planning system (TPS) kernel for carbon radiotherapy in which Katz's Track Structure Theory of cellular survival (TST) is applied as its radiobiology component. The physical beam model is based on available tabularised data, prepared by Monte Carlo simulations of a set of pristine carbon beams of different input energies. An optimisation tool developed for this purpose is used to find the composition of pristine carbon beams of input energies and fluences which delivers a pre-selected depth-dose distribution profile over the spread-out Bragg peak (SOBP) region. Using an extrapolation algorithm, energy-fluence spectra of the primary carbon ions and of all their secondary fragments are obtained over regular steps of beam depths. To obtain survival vs. depth distributions, the TST calculation is applied to the energy-fluence spectra of the mixed field of primary ions and of their secondary products at the given beam depths. Katz's TST offers a unique analytical and quantitative prediction of cell survival in such mixed ion fields. By optimising the pristine beam composition to a published depth-dose profile over the SOBP region of a carbon beam and using TST model parameters representing the survival of CHO (Chinese Hamster Ovary) cells in vitro, it was possible to satisfactorily reproduce a published data set of CHO cell survival vs. depth measurements after carbon ion irradiation. The authors also show by a TST calculation that 'biological dose' is neither linear nor additive. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Oyemitan, Idris A; Elusiyan, Christianah A; Onifade, Ayoola O; Akanmu, Moses A; Oyedeji, Adebola O; McDonald, Armando G
2017-01-01
Curcuma longa (turmeric) is commonly used as spice and also used to treat fever, cough and febrile convulsions in Nigeria. This study determined the chemical composition of the essential oil of C. longa and evaluated its neuropharmacological activity in mice. Essential oil of C. longa (EOCL) fresh rhizome was obtained by hydrodistillation and its chemical composition determined by GC-MS. Acute toxicity (LD 50 ) profile of the essential oil was determined orally (p.o.) and intraperitoneally (i.p.); and the EOCL (50-200 mg/kg, i.p.) was evaluated for its behavioural, anxiolytic, sedative and anticonvulsant activities using appropriate models in Albino mice (Vom Strain, Jos, Nigeria). Analysis of the oil showed the presence of 23 compounds with turmerone (35.9%) being the major component. The LD 50 values obtained for the mice were 2154 mg/kg, p.o., and 693 mg/kg, i.p. The EOCL (50-200 mg/kg, i.p.) caused significant (p < 0.01) inhibition of rearing {F (4,20) = 9} and locomotor {F (3,16) = 42} activity; decreased head dips in hole board {F (4,20) = 4}; increased the time spent in the open arms of the elevated pus maze {F (4,20) = 9}; prolonged total sleeping time {F (4,20) = 21} induced by ketamine injection, and protected mice against pentylenetetrazol-induced convulsions. The major component of the essential oil of this C. longa species was turmerone; the oil was slightly toxic orally but moderately toxic intraperitoneally in mice; exhibited significant anxiolytic, sedative and anticonvulsant activities in mice.
Lello, Stefano; Vittori, Giorgio; Paoletti, Anna Maria; Sorge, Roberto; Guardianelli, Francesca; Melis, Gian Benedetto
2007-11-01
Weight gain is a common problem reported by users of estroprogestins (EPs) and is a frequent reason for EP discontinuation, even if this problem is not confirmed in several clinical studies. We studied the impact of a EP containing ethinyl estradiol (EE) 20 microg plus levonorgestrel (LNG) 100 microg on body weight (BW) and body composition in 47 treated women and 31 women as controls. Also, we studied the effect of this association on metabolic parameters (glycemia, lipid profile). EE20/LNG100 had no significant impact on body weight, body composition (fat mass, fat-free mass, total body water, intracellular water, extracellular water) or metabolic profile in comparison with no treatment. Thus, the use of EE20/LNG100 showed no impact on metabolic parameters, body weight and body composition. This could be important not only for the safety profile of this combination, but also in increasing patient compliance.
NASA Astrophysics Data System (ADS)
De Ridder, Maaike; De Haulleville, Thalès; Kearsley, Elizabeth; Van den Bulcke, Jan; Van Acker, Joris; Beeckman, Hans
2014-05-01
It is commonly acknowledged that allometric equations for aboveground biomass and carbon stock estimates are improved significantly if density is included as a variable. However, not much attention is given to this variable in terms of exact, measured values and density profiles from pith to bark. Most published case-studies obtain density values from literature sources or databases, this way using large ranges of density values and possible causing significant errors in carbon stock estimates. The use of one single fixed value for density is also not recommended if carbon stock increments are estimated. Therefore, our objective is to measure and analyze a large number of tree species occurring in two Biosphere Reserves (Luki and Yangambi). Nevertheless, the diversity of tree species in these tropical forests is too high to perform this kind of detailed analysis on all tree species (> 200/ha). Therefore, we focus on the most frequently encountered tree species with high abundance (trees/ha) and dominance (basal area/ha) for this study. Increment cores were scanned with a helical X-ray protocol to obtain density profiles from pith to bark. This way, we aim at dividing the tree species with a distinct type of density profile into separate groups. If, e.g., slopes in density values from pith to bark remain stable over larger samples of one tree species, this slope could also be used to correct for errors in carbon (increment) estimates, caused by density values from simplified density measurements or density values from literature. In summary, this is most likely the first study in the Congo Basin that focuses on density patterns in order to check their influence on carbon stocks and differences in carbon stocking based on species composition (density profiles ~ temperament of tree species).
Thompson, Dennis; Ooi, Tze C; Anderson, David R; Fisher, Ray; Ewan, Bruce C R
2016-07-01
An earlier demonstration that the relative concentrations of isomers of polychlorinated dibenzofuran do not vary as the flamefront of an iron ore sinter plant progresses through the bed, and profiles are similar for two sinter strands has been widened to include studies of the similarity or otherwise between full scale strand and sinter pot profiles, effect of addition of suppressants and of coke fuel substitution with other combustible materials. For dioxin suppressant addition, a study of the whole of the tetra- penta- and hexaCDF isomer range as separated by the DB5MS chromatography column, indicates no significant change in profile: examination of the ratios of the targeted penta- and hexaCDF isomers suggests the profile is similarly unaffected by coke fuel replacement. Addition of KCl at varied levels has also been shown to have no effect on the 'fingerprint' and there is no indication of any effect by the composition of the sinter mix. The recently published full elution sequence for the DB5MS column is applied to the results obtained using this column. It is confirmed that isomers with 1,9-substitution of chlorine atoms are invariably formed in low concentrations. This is consistent with strong interaction between the 1 and 9 substituted chlorine atoms predicted by DFT thermodynamic calculations. Non-1,9-substituted PCDF equilibrium isomer distributions based on DFT-derived thermodynamic data differ considerably from stack gas distributions obtained using SP2331 column separation. A brief preliminary study indicates the same conclusions (apart from the 1,9-interaction effect) hold for the much smaller content of PCDD. Copyright © 2016 Elsevier Ltd. All rights reserved.
Quasi-static axial crushes on woven jute/polyester AA6063T52 composite tubes
NASA Astrophysics Data System (ADS)
Othman, A.; Ismail, AE
2018-04-01
Quasi-static axial loading have been studied in this paper to determine the behaviour of jute/polyester wrapped on aluminium alloy 6063T52. The filler material also was include into crush box specimen, which is polyurethane (PU) and polystyrene (PE) rigid foam at ranging 40 and 45 kg/m3 densities. All specimen profile was fabricated using hand layup techniques and the length of each specimen were fixed at 100 mm as well as diameter and width of the tube at 50.8 mm. The two types of tubular cross-section were studied of round and square thin-walled profiles and the angle of fibre at 450 were analysed for four layers. Thin walled of aluminium was 1.9 mm and end frontal of each specimen of composite were chamfered at 450 to prevent catastrophic failure mode. The specific absorbed energy (SEA) and crush force efficiency (CFE) were analyses for each specimen to see the behaviour on jute/polyester wrapped on metallic structure can give influence the energy management for automotive application. Result show that the four layers’ jute/polyester with filler material show significant value in term of specific absorbed energy compared empty and polyurethane profiles higher 26.66% for empty and 15.19% compared to polyurethane profiles. It has been found that the thin walled square profile of the jute/polyester tubes with polystyrene foam-filled is found higher respectively 27.42% to 13.13% than empty and polyurethane (PU) foam tubes. An introduce filler material onto thin walled composite profiles gave major advantage increases the mean axial load of 31.87% from 32.94 kN to 48.35 kN from empty to polystyrene thin walled round jute/polyester profiles and 31.7% from 23.11 KN to 33.84 kN from empty to polystyrene thin walled square jute/polyester profiles. Failure mechanisms of the axially loaded composite tubes were also observed and discussed.
Lomonte, Bruno; Fernández, Julián; Sanz, Libia; Angulo, Yamileth; Sasa, Mahmood; Gutiérrez, José María; Calvete, Juan J
2014-06-13
In spite of its small territory of ~50,000km(2), Costa Rica harbors a remarkably rich biodiversity. Its herpetofauna includes 138 species of snakes, of which sixteen pit vipers (family Viperidae, subfamily Crotalinae), five coral snakes (family Elapidae, subfamily Elapinae), and one sea snake (Family Elapidae, subfamily Hydrophiinae) pose potential hazards to human and animal health. In recent years, knowledge on the composition of snake venoms has expanded dramatically thanks to the development of increasingly fast and sensitive analytical techniques in mass spectrometry and separation science applied to protein characterization. Among several analytical strategies to determine the overall protein/peptide composition of snake venoms, the methodology known as 'snake venomics' has proven particularly well suited and informative, by providing not only a catalog of protein types/families present in a venom, but also a semi-quantitative estimation of their relative abundances. Through a collaborative research initiative between Instituto de Biomedicina de Valencia (IBV) and Instituto Clodomiro Picado (ICP), this strategy has been applied to the study of venoms of Costa Rican snakes, aiming to obtain a deeper knowledge on their composition, geographic and ontogenic variations, relationships to taxonomy, correlation with toxic activities, and discovery of novel components. The proteomic profiles of venoms from sixteen out of the 22 species within the Viperidae and Elapidae families found in Costa Rica have been reported so far, and an integrative view of these studies is hereby presented. In line with other venomic projects by research groups focusing on a wide variety of snakes around the world, these studies contribute to a deeper understanding of the biochemical basis for the diverse toxic profiles evolved by venomous snakes. In addition, these studies provide opportunities to identify novel molecules of potential pharmacological interest. Furthermore, the establishment of venom proteomic profiles offers a fundamental platform to assess the detailed immunorecognition of individual proteins/peptides by therapeutic or experimental antivenoms, an evolving methodology for which the term 'antivenomics' was coined (as described in an accompanying paper in this special issue). Venoms represent an adaptive trait and an example of both divergent and convergent evolution. A deep understanding of the composition of venoms and of the principles governing the evolution of venomous systems is of applied importance for exploring the enormous potential of venoms as sources of chemical and pharmacological novelty but also to fight the consequences of snakebite envenomings. Key to this is the identification of evolutionary and ecological trends at different taxonomical levels. However, the evolution of venomous species and their venoms do not always follow the same course, and the identification of structural and functional convergences and divergences among venoms is often unpredictable by a phylogenetic hypothesis. Snake venomics is a proteomic-centered strategy to deconstruct the complex molecular phenotypes the venom proteomes. The proteomic profiles of venoms from sixteen out of the 22 venomous species within the Viperidae and Elapidae families found in Costa Rica have been completed so far. An integrative view of their venom composition, including the identification of geographic and ontogenic variations, is hereby presented. Venom proteomic profiles offer a fundamental platform to assess the detailed immunorecognition of individual venom components by therapeutic or experimental antivenoms. This aspect is reviewed in the companion paper. This article is part of a Special Issue entitled: Proteomics of non-model organisms. Copyright © 2014 Elsevier B.V. All rights reserved.
Distillation time effect on lavender essential oil yield and composition.
Zheljazkov, Valtcho D; Cantrell, Charles L; Astatkie, Tess; Jeliazkova, Ekaterina
2013-01-01
Lavender (Lavandula angustifolia Mill.) is one of the most widely grown essential oil crops in the world. Commercial extraction of lavender oil is done using steam distillation. The objective of this study was to evaluate the effect of the length of the distillation time (DT) on lavender essential oil yield and composition when extracted from dried flowers. Therefore, the following distillation times (DT) were tested in this experiment: 1.5 min, 3 min, 3.75 min, 7.5 min, 15 min, 30 min, 60 min, 90 min, 120 min, 150 min, 180 min, and 240 min. The essential oil yield (range 0.5-6.8%) reached a maximum at 60 min DT. The concentrations of cineole (range 6.4-35%) and fenchol (range 1.7-2.9%) were highest at the 1.5 min DT and decreased with increasing length of the DT. The concentration of camphor (range 6.6-9.2%) reached a maximum at 7.5-15 min DT, while the concentration of linalool acetate (range 15-38%) reached a maximum at 30 min DT. Results suggest that lavender essential oil yield may not increase after 60 min DT. The change in essential oil yield, and the concentrations of cineole, fenchol and linalool acetate as DT changes were modeled very well by the asymptotic nonlinear regression model. DT may be used to modify the chemical profile of lavender oil and to obtain oils with differential chemical profiles from the same lavender flowers. DT must be taken into consideration when citing or comparing reports on lavender essential oil yield and composition.
Santos, Iná S; Barros, Aluísio J D; Matijasevich, Alicia; Zanini, Roberta; Chrestani Cesar, Maria Aurora; Camargo-Figuera, Fabio Alberto; Oliveira, Isabel O; Barros, Fernando C; Victora, Cesar G
2014-10-01
This is an update of the 2004 Pelotas Birth Cohort profile, originally published in 2011. In view of the high prevalence of overweight and mental health problems among Brazilian children, together with the availability of state-of-the-art equipment to assess body composition and diagnostic tests for mental health in childhood, the main outcomes measured in the fifth follow-up (mean age 6.8 years) included child body composition, mental health and cognitive ability. A total of 3722 (90.2%) of the original mothers/carers were interviewed and their children examined in a clinic where they underwent whole-body dual X-ray absorptiometry (DXA), air displacement plethysmography and a 3D photonic scan. Saliva samples for DNA were obtained. Clinical psychologists applied the Development and Well-Being Assessment questionnaire and the Wechsler Intelligence Scale for Children to all children. Results are being compared with those of the two earlier cohorts to assess the health effects of economic growth and full implementation of public policies aimed at reducing social inequalities in the past 30 years. For further information visit the programme website at [http://www.epidemio-ufpel.org.br/site/content/coorte_2004/questionarios.php]. Applications to use the data should be made by contacting 2004 cohort researchers and filling in the application form available at [http://www.epidemio-ufpel.org.br/site/content/estudos/formularios.php]. © The Author 2014; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.
Salerno, Aurelio; Saurina, Javier; Domingo, Concepción
2015-12-30
The manufacture of porous polycaprolactone (PCL) scaffolds containing three different drugs, namely 5-fluorouracil, nicotinamide and triflusal, was investigated in this work with the aim of obtaining bioactive systems with controlled drug delivery capabilities. The scaffolds were prepared by means of a supercritical CO2 (scCO2) foaming technique by optimizing the drug loading process. This was achieved by dissolving the drugs in organic solvents miscible with scCO2 and by mixing these drug/solvent solutions with PCL powder. The as prepared mixtures were further compressed to eliminate air bubbles and finally processed by the scCO2 foaming technique. ScCO2 saturation and foaming conditions were optimized to create the porosity within the samples and to allow for the concomitant removal of the organic solvents. Physical and chemical properties of porous scaffolds, as well as drug content and delivery profiles, were studied by HPLC. The results of this study demonstrated that the composition of the starting PCL/drug/solvent mixtures affected polymer crystallization, scaffold morphology and pore structure features. Furthermore, it was found that drug loading efficiency depended on both initial solution composition and drug solubility in scCO2. Nevertheless, in the case of highly scCO2-soluble drugs, such as triflusal, loading efficiency was improved by adding a proper amount of free drug inside of the pressure vessel. The drug delivery study indicated that release profiles depended mainly upon scaffolds composition and pore structure features. Copyright © 2015 Elsevier B.V. All rights reserved.
MIRA: review of inputs from updated results of the phobos mission
NASA Astrophysics Data System (ADS)
Moroz, V. I.; Korablev, O. I.; Rodin, A. V.; Titov, D. V.
1999-01-01
The future Mars International Reference Atmosphere (MIRA) is intended to replace the present COSPAR Mars Reference Model compiled in 1979 on the basis of Mariner 9 and Viking 1,2 missions results. At the moment, several sources of the post-Viking data potentially useful for MIRA are available. Among them is a data set obtained during Phobos mission in 1989. The interpretation of these data has undergone thorough refinement, so final recommendations for MIRA can be made. The principal points are: 1) vertical profile of water vapor with a ``knee'' at the height about 25 km retrieved in the spring equinox season near equator; 2) variations of water vapor column density including peculiarities on the slopes of high mountains; 3) vertical profiles of ozone; 4) new estimates of CO abundance; 5) surface pressure/height mapping (CO2 altimetry) in selected regions; 6) optical depths of aerosols; 7) vertical profiles of aerosol between surface and 40 km; 8) properties of high altitude ice layers and clouds above mountains; 9) microphysical properties of aerosol particles (size, composition, and number density estimates). The data have been obtained by means of instruments AUGUSTE (UV and NIR spectrometers for limb sounding of the atmosphere using solar occultations), ISM (NIR scanning spectrometer), TERMOSKAN (thermal IR scanning radiometer), KRFM (near-UV and visible multi-band photometer). The observations were performed in equatorial regions during northern spring (solar aerocentric longitudes 8° < Ls < 18°).
Speciated non-methane organic compounds emissions from food cooking in Mexico
NASA Astrophysics Data System (ADS)
Mugica, V.; Vega, E.; Chow, J.; Reyes, E.; Sánchez, G.; Arriaga, J.; Egami, R.; Watson, J.
Non-methane organic compound (NMOC) emissions from different sorts of food preparation sites, were quantified for the first time in Mexico, in order to develop emission profiles for further application in the chemical mass balance receptor model (CMB). Restaurants using charcoal grills and LP gas stoves, "tortillerías", food frying places and rotisseries were sampled using SUMMA ® stainless-steel canisters to analyse NMOC by high-resolution gas chromatography. The results obtained show that profiles determined from food cooking processes have similarities to those found in LP gas combustion, which is the most common fuel in Mexico used for this purpose, although there were differences in the relative composition of propane and butane in both cases. This suggests that, the rates of combustion of propane and butane are different. It has also been detected that propene, a reactive olefin is produced during the combustion process. The obtained profiles of restaurants, rotisseries and fried food show an important contribution of two carbon compounds (ethane, ethylene and acetylene) that can be attributed to the complex process of grease and meat cooking. The presence of these compounds cannot be attributed to vehicular sources since the concentrations are higher than in ambient air. These were also determined from aromatic compounds such as benzene, toluene and xylene in the combustion of vegetal charcoal. The measured concentrations indicate that NMOC emissions from cooking may become an important indoor source of NMOC under crowded conditions in closed places.
Lin, Bin; Braster, Martin; van Breukelen, Boris M.; van Verseveld, Henk W.; Westerhoff, Hans V.; Röling, Wilfred F. M.
2005-01-01
Relationships between community composition of the iron-reducing Geobacteraceae, pollution levels, and the occurrence of biodegradation were established for an iron-reducing aquifer polluted with landfill leachate by using cultivation-independent Geobacteraceae 16S rRNA gene-targeting techniques. Numerical analysis of denaturing gradient gel electrophoresis (DGGE) profiles and sequencing revealed a high Geobacteraceae diversity and showed that community composition within the leachate plume differed considerably from that of the unpolluted aquifer. This suggests that pollution has selected for specific species out of a large pool of Geobacteraceae. DGGE profiles of polluted groundwater taken near the landfill (6- to 39-m distance) clustered together. DGGE profiles from less-polluted groundwater taken further downstream did not fall in the same cluster. Several individual DGGE bands were indicative of either the redox process or the level of pollution. This included a pollution-indicative band that dominated the DGGE profiles from groundwater samples taken close to the landfill (6 to 39 m distance). The clustering of these profiles and the dominance by a single DGGE band corresponded to the part of the aquifer where organic micropollutants and reactive dissolved organic matter were attenuated at relatively high rates. PMID:16204512
Carvajal, A M; Huircan, P; Dezamour, J M; Subiabre, I; Kerr, B; Morales, R; Ungerfeld, E M
2016-05-09
Milk fat composition is important to consumer health. During the last decade, some fatty acids (FA) have received attention because of their functional and beneficial effects on human health. The milk FA profile is affected by both diet and genetics. Differences in milk fat composition are based on biochemical pathways, and candidate genes have been proposed to explain FA profile variation. Here, the association between DGAT1 K232A, SCD1 A293V, and LEPR T945M markers with milk fat composition in southern Chile was evaluated. We selected five herds of Holstein-Friesian, Jersey, Frisón Negro, Montbeliarde, and Overo Colorado cows (pasture-grazed) that received strategic supplementation with concentrates and conserved forages. We genotyped the SNPs and calculated allele frequencies and Hardy-Weinberg equilibrium. Milk fat composition was determined for individual milk samples over a year, and associations between genotypes and milk composition were studied. The most frequent variants for DGAT1, SCD1, and LEPR polymorphisms were GC/GC, C, and C, respectively. The DGAT1 GC/GC allele was associated with lower milk fat and protein content, lower saturated fatty acid levels, and higher polyunsaturated FA (PUFA), n-3 and n-6 FA, and a linolenic acid to cholesterolemic FA ratios, which implied a healthier FA profile. The SCD1 CC genotype was associated with a low cholesterolemic FA content, a high ratio of linolenic acid to cholesterolemic FA, and lower conjugated-linolenic acid and PUFA content. These results suggest the possible modulation of milk fat profiles, using specific genotypes, to improve the nutritional quality of dairy products.
A numerical algorithm of tooth profile of non-circular cylindrical gear
NASA Astrophysics Data System (ADS)
Wang, Xuan
2017-08-01
Non-circular cylindrical gear (NCCG) is a common form of non-circular gear. Different from the circular gear, the tooth profile equation of NCCG cannot be obtained. So it is necessary to use a numerical algorithm to calculate the tooth profile of NCCG. For this reason, this paper presents a simple and highly efficient numerical algorithm to obtain the tooth profile of NCCG. Firstly, the mathematical model of tooth profile envelope of NCCG is established based on the principle of gear shaping, and the tooth profile envelope of NCCG is obtained. Secondly, the polar radius and polar angle of shaper cutter tooth profile are chosen as the criterions, by which the points of NCCG tooth cogging can be screened out. Finally, the boundary of tooth cogging points is extracted by a distance criterion and correspondingly the tooth profile of NCCG is obtained.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brummer, Gordie, E-mail: gbrummer@bu.edu; Photonics Center, Boston University, Boston, Massachusetts 02215; Nothern, Denis
Distributed Bragg reflectors (DBRs) with peak reflectivity at approximately 280 nm, based on compositionally graded Al{sub x}Ga{sub 1−x}N alloys, were grown on 6H-SiC substrates by plasma-assisted molecular beam epitaxy. DBRs with square, sinusoidal, triangular, and sawtooth composition profiles were designed with the transfer matrix method. The crystal structure of these DBRs was studied with high-resolution x-ray diffraction of the (1{sup ¯}015) reciprocal lattice point. The periodicity of the DBR profiles was confirmed with cross-sectional Z-contrast scanning transmission electron microscopy. The peak reflectance of these DBRs with 15.5 periods varies from 77% to 56% with corresponding full width at half maximum ofmore » 17–14 nm. Coupled mode analysis was used to explain the dependence of the reflectivity characteristics on the profile of the graded composition.« less
Molecular Composition Analysis of Distant Targets
NASA Technical Reports Server (NTRS)
Hughes, Gary B.; Lubin, Philip
2017-01-01
This document is the Final Report for NASA Innovative Advanced Concepts (NIAC) Phase I Grant 15-NIAC16A-0145, titled Molecular Composition Analysis of Distant Targets. The research was focused on developing a system concept for probing the molecular composition of cold solar system targets, such as Asteroids, Comets, Planets and Moons from a distant vantage, for example from a spacecraft that is orbiting the target (Hughes et al., 2015). The orbiting spacecraft is equipped with a high-power laser, which is run by electricity from photovoltaic panels. The laser is directed at a spot on the target. Materials on the surface of the target are heated by the laser beam, and begin to melt and then evaporate, forming a plume of asteroid molecules in front of the heated spot. The heated spot glows, producing blackbody illumination that is visible from the spacecraft, via a path through the evaporated plume. As the blackbody radiation from the heated spot passes through the plume of evaporated material, molecules in the plume absorb radiation in a manner that is specific to the rotational and vibrational characteristics of the specific molecules. A spectrometer aboard the spacecraft is used to observe absorption lines in the blackbody signal. The pattern of absorption can be used to estimate the molecular composition of materials in the plume, which originated on the target. Focusing on a single spot produces a borehole, and shallow subsurface profiling of the targets bulk composition is possible. At the beginning of the Phase I research, the estimated Technology Readiness Level (TRL) of the system was TRL-1. During the Phase I research, an end-to-end theoretical model of the sensor system was developed from first principles. The model includes laser energy and optical propagation, target heating, melting and evaporation of target material, plume density, thermal radiation from the heated spot, molecular cross section of likely asteroid materials, and estimation of the absorption profile at a distant spectrometer. Results obtained by executing simulations based on the model provide compelling evidence that the concept of remote laser evaporative molecular absorption spectroscopy is feasible. In this document, technical details of the model are presented, and results of simulations are described that indicate the utility of the proposed sensor system. Additionally, an asteroid rendezvous mission is analyzed, with a survey of system requirements to accomplish molecular composition analysis of the asteroid. Based on positive theoretical results obtained during Phase I, the estimated TRL of the system is now TRL-2. This document also describes potential future research and experimentation that could push the system to TRL-4 within 2 years. Steps required for construction of a laboratory prototype are described. An experiment to test predictions of the theory is described, based on the laboratory prototype setup.
One-Sided Measurement Approach on Ultrasonic Beam Path Analysis in CFRP Composite Laminates
NASA Astrophysics Data System (ADS)
Im, K. H.; Hsu, D. K.; Kim, H. J.; Song, S. J.; Dayal, V.; Barnard, D.; Park, J. W.; Lee, K. S.; Yang, Y. J.; Yang, I. Y.
2008-02-01
Composite materials are attractive for a wide range of applications because of high performance engineering structures. In particular, the importance of carbon-fiber reinforced plastics (CFRP) has been generally recognized in both space and civil aircraft industries; so, CFRP composite laminates are widely used. It is very important to detect defects in composite laminates because they cause the mechanical properties (stiffness, strength) of the laminate to be reduced. As well known for ultrasonic technique for evaluating the defect of CFRP composite laminates, a pitch-catch technique was found to be more practical than normal incidence backwall echo of longitudinal wave to arbitrary flaws in the composite, including fiber orientation, low level porosity, ply waviness, and cracks. The measurement depth using Rayleigh probes can be increased by increasing the separation distance of the transmitting and receiving probes. Also, with the aid of the automatic scanner, the one-sided pitch-catch probe was used to produce C-scan images for mapping out the images with beam profiles. Especially pitch-catch beam path was nondestructively characterized for the specimens when measuring a peak-to-peak amplitude and time-of-flight in order to build the beam profile modeling in the unidirectional CFRP composite laminates. Also, the pitch-catch simulation was performed to predict the beam profile trend of wave propagation in the unidirectional CF/Epoxy composite laminates. Therefore, it is found that the experimentally Rayleigh wave variation of pitch-catch ultrasonic signal was consistent with simulated results and one-side ultrasonic measurement might be very useful to detect the defects in CFRP composites.
Seismic Velocity Gradients Across the Transition Zone
NASA Astrophysics Data System (ADS)
Escalante, C.; Cammarano, F.; de Koker, N.; Piazzoni, A.; Wang, Y.; Marone, F.; Dalton, C.; Romanowicz, B.
2006-12-01
One-D elastic velocity models derived from mineral physics do a notoriously poor job at predicting the velocity gradients in the upper mantle transition zone, as well as some other features of models derived from seismological data. During the 2006 CIDER summer program, we computed Vs and Vp velocity profiles in the upper mantle based on three different mineral physics approaches: two approaches based on the minimization of Gibbs Free Energy (Stixrude and Lithgow-Bertelloni, 2005; Piazzoni et al., 2006) and one obtained by using experimentally determined phase diagrams (Weidner and Wang, 1998). The profiles were compared by assuming a vertical temperature profile and two end-member compositional models, the pyrolite model of Ringwood (1979) and the piclogite model of Anderson and Bass (1984). The predicted seismic profiles, which are significantly different from each other, primarily due to different choices of properties of single minerals and their extrapolation with temperature, are tested against a global dataset of P and S travel times and spheroidal and toroidal normal mode eigenfrequencies. All the models derived using a potential temperature of 1600K predict seismic velocities that are too slow in the upper mantle, suggesting the need to use a colder geotherm. The velocity gradient in the transition zone is somewhat better for piclogite than for pyrolite, possibly indicating the need to increase Ca content. The presence of stagnant slabs in the transition zone is a possible explanation for the need for 1) colder temperature and 2) increased Ca content. Future improvements in seismic profiles obtained from mineral physics will arise from better knowledge of elastic properties of upper mantle constituents and aggregates at high temperature and pressure, a better understanding of differences between thermodynamic models, and possibly the effect of water through and on Q. High resolution seismic constraints on velocity jumps at 400 and 660 km also need to be included. earth.org/2006/workshop.html
Development of in vitro-in vivo correlation of parenteral naltrexone loaded polymeric microspheres.
Andhariya, Janki V; Shen, Jie; Choi, Stephanie; Wang, Yan; Zou, Yuan; Burgess, Diane J
2017-06-10
Establishment of in vitro-in vivo correlations (IVIVCs) for parenteral polymeric microspheres has been very challenging, due to their complex multiphase release characteristics (which is affected by the nature of the drug) as well as the lack of compendial in vitro release testing methods. Previously, a Level A correlation has been established and validated for polymeric microspheres containing risperidone (a practically water insoluble small molecule drug). The objectives of the present study were: 1) to investigate whether a Level A IVIVC can be established for polymeric microspheres containing another small molecule drug with different solubility profiles compared to risperidone; and 2) to determine whether release characteristic differences (bi-phasic vs tri-phasic) between microspheres can affect the development and predictability of IVIVCs. Naltrexone was chosen as the model drug. Three compositionally equivalent formulations of naltrexone microspheres with different release characteristics were prepared using different manufacturing processes. The critical physicochemical properties (such as drug loading, particle size, porosity, and morphology) as well as the in vitro release characteristics of the prepared naltrexone microspheres and the reference-listed drug (Vivitrol®) were determined. The pharmacokinetics of the naltrexone microspheres were investigated using a rabbit model. The obtained pharmacokinetic profiles were deconvoluted using the Loo-Riegelman method, and compared with the in vitro release profiles of the naltrexone microspheres obtained using USP apparatus 4. Level A IVIVCs were established and validated for predictability. The results demonstrated that the developed USP 4 method was capable of detecting manufacturing process related performance changes, and most importantly, predicting the in vivo performance of naltrexone microspheres in the investigated animal model. A critical difference between naltrexone and risperidone loaded microspheres is their respective bi-phasic and tri-phasic release profiles with varying burst release and lag phase. These variations in release profiles affect the development of IVIVCs. Nevertheless, IVIVCs have been established and validated for polymeric microspheres with different release characteristics. Copyright © 2017. Published by Elsevier B.V.
Honeyfield, Dale C.; Maloney, Kelly O.
2015-01-01
Fatty acids are integral components of periphyton and differ among algal taxa. We examined seasonal patterns in periphyton fatty acids in six minimally disturbed headwater streams in Pennsylvania’s Appalachian Mountains, USA. Environmental data and periphyton were collected across four seasons for fatty acid and algal taxa content. Non-metric multidimensional scaling ordination suggested significant seasonal differences in fatty acids; an ordination on algal composition revealed similar seasonal patterns, but with slightly weaker separation of summer and fall. Summer and fall fatty acid profiles were driven by temperature, overstory cover, and conductivity and winter profiles by measures of stream size. Ordination on algal composition suggested that summer and fall communities were driven by overstory and temperature, whereas winter communities were driven by velocity. The physiologically important fatty acid 18:3ω6 was highest in summer and fall. Winter samples had the highest 20:3ω3. Six saturated fatty acids differed among the seasons. Periphyton fatty acids profiles appeared to reflect benthic algal species composition. This suggests that periphyton fatty acid composition can be useful in characterizing basal food resources and stream water quality.
Gyurcsányi, R E; Pergel, E; Nagy, R; Kapui, I; Lan, B T; Tóth, K; Bitter, I; Lindner, E
2001-05-01
Scanning electrochemical microscopy (SECM) supplemented with potentiometric measurements was used to follow the time-dependent buildup of a steady-state diffusion layer at the aqueous-phase boundary of lead ion-selective electrodes (ISEs). Differential pulse voltammetry is adapted to SECM for probing the local concentration profiles at the sample side of solvent polymeric membranes. Major factors affecting the membrane transport-related surface concentrations were identified from SECM data and the potentiometric transients obtained under different experimental conditions (inner filling solution composition, membrane thickness, surface pretreatment). The amperometrically determined surface concentrations correlated well with the lower detection limits of the lead ion-selective electrodes.
Lateral excitonic switching in vertically stacked quantum dots
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jarzynka, Jarosław R.; McDonald, Peter G.; Galbraith, Ian
2016-06-14
We show that the application of a vertical electric field to the Coulomb interacting system in stacked quantum dots leads to a 90° in-plane switching of charge probability distribution in contrast to a single dot, where no such switching exists. Results are obtained using path integral quantum Monte Carlo with realistic dot geometry, alloy composition, and piezo-electric potential profiles. The origin of the switching lies in the strain interactions between the stacked dots hence the need for more than one layer of dots. The lateral polarization and electric field dependence of the radiative lifetimes of the excitonic switch are alsomore » discussed.« less
NASA Technical Reports Server (NTRS)
Jaunky, Navin; Knight, Norman F., Jr.; Ambur, Damodar R.
1995-01-01
A smeared stiffener theory for stiffened panels is presented that includes skin-stiffener interaction effects. The neutral surface profile of the skin-stiffener combination is developed analytically using the minimum potential energy principle and statics conditions. The skin-stiffener interaction is accounted for by computing the stiffness due to the stiffener and the skin in the skin-stiffener region about the neutral axis at the stiffener. Buckling load results for axially stiffened, orthogrid, and general grid-stiffened panels are obtained using the smeared stiffness combined with a Rayleigh-Ritz method and are compared with results from detailed finite element analyses.
NASA Astrophysics Data System (ADS)
Gao, Dongyue; Wang, Yishou; Wu, Zhanjun; Rahim, Gorgin; Bai, Shengbao
2014-05-01
The detection capability of a given structural health monitoring (SHM) system strongly depends on its sensor network placement. In order to minimize the number of sensors while maximizing the detection capability, optimal design of the PZT sensor network placement is necessary for structural health monitoring (SHM) of a full-scale composite horizontal tail. In this study, the sensor network optimization was simplified as a problem of determining the sensor array placement between stiffeners to achieve the desired the coverage rate. First, an analysis of the structural layout and load distribution of a composite horizontal tail was performed. The constraint conditions of the optimal design were presented. Then, the SHM algorithm of the composite horizontal tail under static load was proposed. Based on the given SHM algorithm, a sensor network was designed for the full-scale composite horizontal tail structure. Effective profiles of cross-stiffener paths (CRPs) and uncross-stiffener paths (URPs) were estimated by a Lamb wave propagation experiment in a multi-stiffener composite specimen. Based on the coverage rate and the redundancy requirements, a seven-sensor array-network was chosen as the optimal sensor network for each airfoil. Finally, a preliminary SHM experiment was performed on a typical composite aircraft structure component. The reliability of the SHM result for a composite horizontal tail structure under static load was validated. In the result, the red zone represented the delamination damage. The detection capability of the optimized sensor network was verified by SHM of a full-scale composite horizontal tail; all the diagnosis results were obtained in two minutes. The result showed that all the damage in the monitoring region was covered by the sensor network.
Bandgap profiling in CIGS solar cells via valence electron energy-loss spectroscopy
NASA Astrophysics Data System (ADS)
Deitz, Julia I.; Karki, Shankar; Marsillac, Sylvain X.; Grassman, Tyler J.; McComb, David W.
2018-03-01
A robust, reproducible method for the extraction of relative bandgap trends from scanning transmission electron microscopy (STEM) based electron energy-loss spectroscopy (EELS) is described. The effectiveness of the approach is demonstrated by profiling the bandgap through a CuIn1-xGaxSe2 solar cell that possesses intentional Ga/(In + Ga) composition variation. The EELS-determined bandgap profile is compared to the nominal profile calculated from compositional data collected via STEM-based energy dispersive X-ray spectroscopy. The EELS based profile is found to closely track the calculated bandgap trends, with only a small, fixed offset difference. This method, which is particularly advantageous for relatively narrow bandgap materials and/or STEM systems with modest resolution capabilities (i.e., >100 meV), compromises absolute accuracy to provide a straightforward route for the correlation of local electronic structure trends with nanoscale chemical and physical structure/microstructure within semiconductor materials and devices.
NASA Astrophysics Data System (ADS)
Christen, Hans M.; Puretzky, Alex A.; Cui, Hongtao; Lowndes, Douglas H.; Belay, Kalayu; Geohegan, David B.
2004-03-01
The growth of dense forests of vertically aligned arrays of multi-walled carbon nanotubes (VAA-MWNTs) by chemical vapor deposition [CVD] from a single metallic catalyst layer typically self-terminates after only a few hundred microns of tube length. In order to obtain maximal growth to long lengths, a systematic simultaneous study of catalyst composition and thickness is needed performed here by a compositional-spread approach. Using Pulsed-Laser Deposition (PLD), metallic layers with a wedge-shaped thickness profile are deposited onto Al-coated silicon substrates. High temperature annealing of the metal catalyst films in flowing Ar/H2 gas followed by the one-hour growth of VA-MWNTs by CVD using acetylene gas yields VAA-MWNTs. Tube height (and thus the catalytic activity) is determined as function of position and can be analyzed as a function of catalyst thickness and composition. A dependence of tube height as function of catalyst composition (Mo/Fe ratio) demonstrates that a specific catalyst composition exhibits a local maximum in catalytic activity, permitting the extension of nanotube array growth up to 4 millimeters in height. Other combinations of catalysts and the growth of single-walled tubes will be discussed. This research was sponsored by the U.S. Department of Energy under contract DE-AC05-00OR22725 with the Oak Ridge National Laboratory, managed by UT-Battelle, LLC, and the Laboratory-Directed Research and Development Program at ORNL.
Nanoscopic diffusion studies on III-V compound semiconductor structures: Experiment and theory
NASA Astrophysics Data System (ADS)
Gonzalez Debs, Mariam
The electronic structure of multilayer semiconductor heterostructures is affected by the detailed compositional profiles throughout the structure and at critical interfaces. The extent of interdiffusion across these interfaces places limits on both the processing time and temperatures for many applications based on the resultant compositional profile and associated electronic structure. Atomic and phenomenological methods were used in this work through the combination of experiment and theory to understand the nanoscopic mechanisms in complex heterostructures. Two principal studies were conducted. Tin diffusion in GaAs was studied by fitting complex experimental diffusion profiles to a phenomenological model which involved the diffusion of substitutional and interstitial dopant atoms. A methodology was developed combining both the atomistic model and the use of key features within these experimentally-obtained diffusion profiles to determine meaningful values of the transport and defect reaction rate parameters. Interdiffusion across AlSb/GaSb multi-quantum well interfaces was also studied. The chemical diffusion coefficient characterizing the AlSb/GaSb diffusion couple was quantitatively determined by fitting the observed photoluminescence (PL) peak shifts to the solution of the Schrodinger equation using a potential derived from the solution of the diffusion equation to quantify the interband transition energy shifts. First-principles calculations implementing Density Functional Theory were performed to study the thermochemistry of point defects as a function of local environment, allowing a direct comparison of interfacial and bulk diffusion phenomena within these nanoscopic structures. Significant differences were observed in the Ga and Al vacancy formation energies at the AlSb/GaSb interface when compared to bulk AlSb and GaSb with the largest change found for Al vacancies. The AlSb/GaSb structures were further studied using positron annihilation spectroscopy (PAS) to investigate the role of vacancies in the interdiffusion of Al and Ga in the superlattices. The PL and PAS experimental techniques together with the phenomenological and atomistic modeling allowed for the determination of the underlying mass transport mechanisms at the nanoscale.
Crystal growth of compound semiconductors in a low-gravity environment (InGaAs crystals) (M-22)
NASA Technical Reports Server (NTRS)
Tatsumi, Masami
1993-01-01
Compound semiconductor crystals, such as gallium arsenide and indium phosphide crystals, have many interesting properties that silicon crystals lack, and they are expected to be used as materials for optic and/or electro-optic integrated devices. Generally speaking, alloy semiconductors, which consist of more than three elements, demonstrate new functions. For example, values of important parameters, such as lattice constant and emission wavelength, can be chosen independently. However, as it is easy for macroscopic and/or microscopic fluctuations of composition to occur in alloy semiconductor crystals, it is difficult to obtain crystals having homogeneous properties. Macroscopic change of composition in a crystal is caused by the segregation phenomenon. This phenomenon is due to a continuous change in the concentration of constituent elements at the solid-liquid interfacing during solidification. On Earth, attempts were made to obtain a crystal with homogeneous composition by maintaining a constant melt composition near the solid-liquid interface, through suppression of the convection flow of the melt by applying a magnetic field. However, the attempt was not completely successful. Convective flow does not occur in microgravity because the gravity in space is from four to six orders of magnitude less than that on Earth. In such a case, mass transfer in the melt is dominated by the diffusion phenomenon. So, if crystal growth is carried out at a rate that is higher than the rate of mass transfer due to this phenomenon, it is expected that crystals having a homogeneous composition will be obtained. In addition, it is also possible that microscopic composition fluctuations (striation) may disappear because microscopic fluctuations diminish in the absence of convection. We are going to grow a bulk-indium gallium arsenide (InGaAs) crystal using the gradient heating furnace (GHF) in the first material processing test (FMPT). The structure of the sample is shown where InGaAs polycrystals in a crucible are doubly sealed in two quartz tubes for safety. The GHF consists of two zones, namely, high temperature and low temperature zones, which results in a large temperature gradient at the interface. Crystal growth is performed by moving the furnace (i.e. the temperature profile) from the left to right at a definite rate. Thus, we will grow crystals both on Earth and in space under the same conditions. As previously described, it is possible to obtain good quality crystals which are homogeneous in composition both macroscopically and microscopically due to the lack of convection in space. We are planning to study the effects of convection on crystal growth from a melt by comparing and characterizing the properties of crystals grown on Earth with those grown in space.
Kao, Hui-Ju; Weng, Shun-Long; Huang, Kai-Yao; Kaunang, Fergie Joanda; Hsu, Justin Bo-Kai; Huang, Chien-Hsun; Lee, Tzong-Yi
2017-12-21
Carbonylation, which takes place through oxidation of reactive oxygen species (ROS) on specific residues, is an irreversibly oxidative modification of proteins. It has been reported that the carbonylation is related to a number of metabolic or aging diseases including diabetes, chronic lung disease, Parkinson's disease, and Alzheimer's disease. Due to the lack of computational methods dedicated to exploring motif signatures of protein carbonylation sites, we were motivated to exploit an iterative statistical method to characterize and identify carbonylated sites with motif signatures. By manually curating experimental data from research articles, we obtained 332, 144, 135, and 140 verified substrate sites for K (lysine), R (arginine), T (threonine), and P (proline) residues, respectively, from 241 carbonylated proteins. In order to examine the informative attributes for classifying between carbonylated and non-carbonylated sites, multifarious features including composition of twenty amino acids (AAC), composition of amino acid pairs (AAPC), position-specific scoring matrix (PSSM), and positional weighted matrix (PWM) were investigated in this study. Additionally, in an attempt to explore the motif signatures of carbonylation sites, an iterative statistical method was adopted to detect statistically significant dependencies of amino acid compositions between specific positions around substrate sites. Profile hidden Markov model (HMM) was then utilized to train a predictive model from each motif signature. Moreover, based on the method of support vector machine (SVM), we adopted it to construct an integrative model by combining the values of bit scores obtained from profile HMMs. The combinatorial model could provide an enhanced performance with evenly predictive sensitivity and specificity in the evaluation of cross-validation and independent testing. This study provides a new scheme for exploring potential motif signatures at substrate sites of protein carbonylation. The usefulness of the revealed motifs in the identification of carbonylated sites is demonstrated by their effective performance in cross-validation and independent testing. Finally, these substrate motifs were adopted to build an available online resource (MDD-Carb, http://csb.cse.yzu.edu.tw/MDDCarb/ ) and are also anticipated to facilitate the study of large-scale carbonylated proteomes.
NASA Astrophysics Data System (ADS)
Qin, F. X.; Peng, H. X.; Popov, V. V.; Phan, M. H.
2011-02-01
Composites consisting of glass-coated amorphous microwire Co 68.59Fe 4.84Si 12.41B 14.16 and 913 E-glass prepregs were designed and fabricated. The influences of tensile stress, annealing and number of composite layers on the giant magneto-impedance (GMI) and giant stress-impedance (GSI) effects in these composites were investigated systematically. It was found that the application of tensile stress along the microwire axis or an increase in the number of composite layers reduced the GMI effect and increased the circular anisotropy field, while the annealing treatment had a reverse effect. The value of matrix-wire interfacial stress calculated via the GMI profiles coincided with the value of the applied effective tensile stress to yield similar GMI profiles. Enhancement of the GSI effect was achieved in the composites relative to their single microwire inclusion. These findings are important for the development of functional microwire-based composites for magnetic- and stress-sensing applications. They also open up a new route for probing the interfacial stress in fibre-reinforced polymer (FRP) composites.
Probabilistic Analysis of a SiC/SiC Ceramic Matrix Composite Turbine Vane
NASA Technical Reports Server (NTRS)
Murthy, Pappu L. N.; Nemeth, Noel N.; Brewer, David N.; Mital, Subodh
2004-01-01
To demonstrate the advanced composite materials technology under development within the Ultra-Efficient Engine Technology (UEET) Program, it was planned to fabricate, test, and analyze a turbine vane made entirely of silicon carbide-fiber-reinforced silicon carbide matrix composite (SiC/SiC CMC) material. The objective was to utilize a five-harness satin weave melt-infiltrated (MI) SiC/SiC composite material developed under this program to design and fabricate a stator vane that can endure 1000 hours of engine service conditions. The vane was designed such that the expected maximum stresses were kept within the proportional limit strength of the material. Any violation of this design requirement was considered as the failure. This report presents results of a probabilistic analysis and reliability assessment of the vane. Probability of failure to meet the design requirements was computed. In the analysis, material properties, strength, and pressure loading were considered as random variables. The pressure loads were considered normally distributed with a nominal variation. A temperature profile on the vane was obtained by performing a computational fluid dynamics (CFD) analysis and was assumed to be deterministic. The results suggest that for the current vane design, the chance of not meeting design requirements is about 1.6 percent.
Remodeling of the neuromuscular junction precedes sarcopenia related alterations in myofibers.
Deschenes, Michael R; Roby, Mackenzie A; Eason, Margaret K; Harris, M Brennan
2010-05-01
Several mechanisms contributing to the etiology of sarcopenia (age-related loss of muscle size) have been postulated. One of these attributes the loss of muscle mass to a preceding age-related denervation of myofibers. The aim of this study was to determine if signs of denervation were apparent at the neuromuscular junction (NMJ) before fiber atrophy, or fiber type conversion could be documented, and to reveal if a muscle's activity level impacts its sensitivity to age-related denervation. Plantaris and soleus muscles were obtained from young adult (10 months) and early aged (21 months) rats. Pre- and post-synaptic NMJ morphology was quantified with cytofluorescent staining of nerve terminal branches and endplate regions, respectively. Myofiber profiles (fiber size and fiber type composition) were assessed with histochemical procedures. Results show that in the lightly recruited plantaris, significant (P<0.05) signs of denervation were noted in aged rats, while the same muscles displayed no change in myofiber profile. In the heavily recruited soleus, however, there was little evidence of denervation, and again no alterations in myofiber profile. These results indicate that age-related denervation occurs before myofiber atrophy, and that high amounts of neuromuscular activity may delay the onset of age-related denervation and sarcopenia.
Joyce, Alison P; Wang, Mengmeng; Lawrence-Henderson, Rosemary; Filliettaz, Cynthia; Leung, Sheldon S; Xu, Xin; O'Hara, Denise M
2014-07-01
The purpose of this study was to validate the approach of serial sampling from one mouse through ligand binding assay (LBA) quantification of dosed biotherapeutic in diluted whole blood to derive a pharmacokinetic (PK) profile. This investigation compared PK parameters obtained using serial and composite sampling methods following administration of human IgG monoclonal antibody. The serial sampling technique was established by collecting 10 μL of blood via tail vein at each time point following drug administration. Blood was immediately diluted into buffer followed by analyte quantitation using Gyrolab to derive plasma concentrations. Additional studies were conducted to understand matrix and sampling site effects on drug concentrations. The drug concentration profiles, irrespective of biological matrix, and PK parameters using both sampling methods were not significantly different. There were no sampling site effects on drug concentration measurements except that concentrations were slightly lower in sodium citrated plasma than other matrices. We recommend the application of mouse serial sampling, particularly with limiting drug supply or specialized animal models. Overall the efficiencies gained by serial sampling were 40-80% savings in study cost, animal usage, study length and drug conservation while inter-subject variability across PK parameters was less than 30%.
Montenegro, Gloria; Díaz-Forestier, Javiera; Fredes, Carolina; Rodríguez, Sharon
2013-01-01
Quillaja saponaria Mol. (Quillajaceae) is one of the most important melliferous species in Chile, mainly as a source of monofloral honey. Honey made by A. mellifera presents biological activity against pathogens and antioxidant capacity associated with the presence of phenolic compounds deriving from the nectar, as a result of bee honey foraging. The aim of this study was to identify and quantify the phenolic compounds from the floral nectar of Q. saponaria and the honey made in apiaries in the central zone, and compare the composition of the chromatographic profiles of nectar and honey to known phenolic compounds. The results obtained by HPLC-DAD (high-performance liquid chromatography with diode-array detection) showed a similar profile of phenolic compounds, in which gallic acid, myricetin, rutin, quercetin and naringenin were identified. The phenolic compounds detected could be used as a reference for future studies for determining potential chemical markers of this honey, complementing the present identification of honeys by determining their botanical origin. The identification of bioindicators of the floral origins for honey of this species could provide added value to honey commercialization by certifying the botanical origin of their chemical features and biological attributes.
Characterisation of nickel silicide thin films by spectroscopy and microscopy techniques.
Bhaskaran, M; Sriram, S; Holland, A S; Evans, P J
2009-01-01
This article discusses the formation and detailed materials characterisation of nickel silicide thin films. Nickel silicide thin films have been formed by thermally reacting electron beam evaporated thin films of nickel with silicon. The nickel silicide thin films have been analysed using Auger electron spectroscopy (AES) depth profiles, secondary ion mass spectrometry (SIMS), and Rutherford backscattering spectroscopy (RBS). The AES depth profile shows a uniform NiSi film, with a composition of 49-50% nickel and 51-50% silicon. No oxygen contamination either on the surface or at the silicide-silicon interface was observed. The SIMS depth profile confirms the existence of a uniform film, with no traces of oxygen contamination. RBS results indicate a nickel silicide layer of 114 nm, with the simulated spectra in close agreement with the experimental data. Atomic force microscopy and transmission electron microscopy have been used to study the morphology of the nickel silicide thin films. The average grain size and average surface roughness of these films was found to be 30-50 and 0.67 nm, respectively. The film surface has also been studied using Kikuchi patterns obtained by electron backscatter detection.
Cisneros, Fausto H; Paredes, Daniel; Arana, Adrian; Cisneros-Zevallos, Luis
2014-06-04
The effect of roasting of Sacha-inchi (Plukenetia volubilis L.) seeds on the oxidative stability and composition of its oil was investigated. The seeds were subjected to light, medium and high roasting intensities. Oil samples were subjected to high-temperature storage at 60 °C for 30 days and evaluated for oxidation (peroxide value and p-anisidine), antioxidant activity (total phenols and DPPH assay), and composition (tocopherol content and fatty acid profile). Results showed that roasting partially increased oil oxidation and its antioxidant capacity, slightly decreased tocopherol content, and did not affect the fatty acid profile. During storage, oxidation increased for all oil samples, but at a slower rate for oils from roasted seeds, likely due to its higher antioxidant capacity. Also, tocopherol content decreased significantly, and a slight modification of the fatty acid profile suggested that α-linolenic acid oxidized more readily than other fatty acids present.
Analysis of Surface and Bulk Behavior in Ni-Pd Alloys
NASA Technical Reports Server (NTRS)
Bozzolo, Guillermo; Noebe, Rondald D.
2003-01-01
The most salient features of the surface structure and bulk behavior of Ni-Pd alloys have been studied using the BFS method for alloys. Large-scale atomistic simulations were performed to investigate surface segregation profiles as a function of temperature, crystal face, and composition. Pd enrichment of the first layer was observed in (111) and (100) surfaces, and enrichment of the top two layers occurred for (110) surfaces. In all cases, the segregation profile shows alternate planes enriched and depleted in Pd. In addition, the phase structure of bulk Ni-Pd alloys as a function of temperature and composition was studied. A weak ordering tendency was observed at low temperatures, which helps explain the compositional oscillations in the segregation profiles. Finally, based on atom-by-atom static energy calculations, a comprehensive explanation for the observed surface and bulk features will be presented in terms of competing chemical and strain energy effects.
Archival processes of the water stable isotope signal in East Antarctic ice cores
NASA Astrophysics Data System (ADS)
Casado, Mathieu; Landais, Amaelle; Picard, Ghislain; Münch, Thomas; Laepple, Thomas; Stenni, Barbara; Dreossi, Giuliano; Ekaykin, Alexey; Arnaud, Laurent; Genthon, Christophe; Touzeau, Alexandra; Masson-Delmotte, Valerie; Jouzel, Jean
2018-05-01
The oldest ice core records are obtained from the East Antarctic Plateau. Water isotopes are key proxies to reconstructing past climatic conditions over the ice sheet and at the evaporation source. The accuracy of climate reconstructions depends on knowledge of all processes affecting water vapour, precipitation and snow isotopic compositions. Fractionation processes are well understood and can be integrated in trajectory-based Rayleigh distillation and isotope-enabled climate models. However, a quantitative understanding of processes potentially altering snow isotopic composition after deposition is still missing. In low-accumulation sites, such as those found in East Antarctica, these poorly constrained processes are likely to play a significant role and limit the interpretability of an ice core's isotopic composition. By combining observations of isotopic composition in vapour, precipitation, surface snow and buried snow from Dome C, a deep ice core site on the East Antarctic Plateau, we found indications of a seasonal impact of metamorphism on the surface snow isotopic signal when compared to the initial precipitation. Particularly in summer, exchanges of water molecules between vapour and snow are driven by the diurnal sublimation-condensation cycles. Overall, we observe in between precipitation events modification of the surface snow isotopic composition. Using high-resolution water isotopic composition profiles from snow pits at five Antarctic sites with different accumulation rates, we identified common patterns which cannot be attributed to the seasonal variability of precipitation. These differences in the precipitation, surface snow and buried snow isotopic composition provide evidence of post-deposition processes affecting ice core records in low-accumulation areas.
NASA Astrophysics Data System (ADS)
Mainali, Laxman; Feix, Jimmy B.; Hyde, James S.; Subczynski, Witold K.
2011-10-01
There are no easily obtainable EPR spectral parameters for lipid spin labels that describe profiles of membrane fluidity. The order parameter, which is most often used as a measure of membrane fluidity, describes the amplitude of wobbling motion of alkyl chains relative to the membrane normal and does not contain explicitly time or velocity. Thus, this parameter can be considered as nondynamic. The spin-lattice relaxation rate ( T1-1) obtained from saturation-recovery EPR measurements of lipid spin labels in deoxygenated samples depends primarily on the rotational correlation time of the nitroxide moiety within the lipid bilayer. Thus, T1-1 can be used as a convenient quantitative measure of membrane fluidity that reflects local membrane dynamics. T1-1 profiles obtained for 1-palmitoyl-2-( n-doxylstearoyl)phosphatidylcholine ( n-PC) spin labels in dimyristoylphosphatidylcholine (DMPC) membranes with and without 50 mol% cholesterol are presented in parallel with profiles of the rotational diffusion coefficient, R⊥, obtained from simulation of EPR spectra using Freed's model. These profiles are compared with profiles of the order parameter obtained directly from EPR spectra and with profiles of the order parameter obtained from simulation of EPR spectra. It is shown that T1-1 and R⊥ profiles reveal changes in membrane fluidity that depend on the motional properties of the lipid alkyl chain. We find that cholesterol has a rigidifying effect only to the depth occupied by the rigid steroid ring structure and a fluidizing effect at deeper locations. These effects cannot be differentiated by profiles of the order parameter. All profiles in this study were obtained at X-band (9.5 GHz).
Estimation of composite hydraulic resistance in ice-covered alluvial streams
NASA Astrophysics Data System (ADS)
Ghareh Aghaji Zare, Soheil; Moore, Stephanie A.; Rennie, Colin D.; Seidou, Ousmane; Ahmari, Habib; Malenchak, Jarrod
2016-02-01
Formation, propagation, and recession of ice cover introduce a dynamic boundary layer to the top of rivers during northern winters. Ice cover affects water velocity magnitude and distribution, water level and consequently conveyance capacity of the river. In this research, total resistance, i.e., "composite resistance," is studied for a 4 month period including stable ice cover, breakup, and open water stages in Lower Nelson River (LNR), northern Manitoba, Canada. Flow and ice characteristics such as water velocity and depth and ice thickness and condition were measured continuously using acoustic techniques. An Acoustic Doppler Current Profiler (ADCP) and Shallow Water Ice Profiling Sonar (SWIPS) were installed simultaneously on a bottom mount and deployed for this purpose. Total resistance to the flow and boundary roughness are estimated using measured bulk hydraulic parameters. A novel method is developed to calculate composite resistance directly from measured under ice velocity profiles. The results of this method are compared to the measured total resistance and to the calculated composite resistance using formulae available in literature. The new technique is demonstrated to compare favorably to measured total resistance and to outperform previously available methods.
NASA Astrophysics Data System (ADS)
Shao, Zhenzhen; Jiang, B. W.; Li, Aigen; Gao, Jian; Lv, Zhangpan; Yao, Jiawen
2018-05-01
The 9.7 μm interstellar spectral feature, arising from the Si-O stretch of amorphous silicate dust, is the strongest extinction feature in the infrared (IR). In principle, the spectral profile of this feature could allow one to diagnose the mineralogical composition of interstellar silicate material. However, observationally, the 9.7 μm interstellar silicate extinction profile is not well determined. Here we utilize the Spitzer/IRS spectra of five early-type (one O- and four B-type) stars and compare them with that of unreddened stars of the same spectral type to probe the interstellar extinction of silicate dust around 9.7 μm. We find that, while the silicate extinction profiles all peak at ˜ 9.7 μm, two stars exhibit a narrow feature of FWHM ˜ 2.0 μm and three stars display a broad feature of FWHM ˜ 3.0 μm. We also find that the width of the 9.7 μm extinction feature does not show any environmental dependence. With a FWHM of ˜ 2.2 μm, the mean 9.7 μm extinction profile, obtained by averaging over our five stars, closely resembles that of the prototypical diffuse interstellar medium along the lines of sight toward Cyg OB2 No. 12 and WR 98a. Finally, an analytical formula is presented to parameterize the interstellar extinction in the IR at 0.9 μm ≲ λ ≲ 15 μm.
Plantinga, Esther A; Bosch, Guido; Hendriks, Wouter H
2011-10-01
Cats are strict carnivores and in the wild rely on a diet solely based on animal tissues to meet their specific and unique nutritional requirements. Although the feeding ecology of cats in the wild has been well documented in the literature, there is no information on the precise nutrient profile to which the cat's metabolism has adapted. The present study aimed to derive the dietary nutrient profile of free-living cats. Studies reporting the feeding habits of cats in the wild were reviewed and data on the nutrient composition of the consumed prey items obtained from the literature. Fifty-five studies reported feeding strategy data of cats in the wild. After specific exclusion criteria, twenty-seven studies were used to derive thirty individual dietary nutrient profiles. The results show that feral cats are obligatory carnivores, with their daily energy intake from crude protein being 52 %, from crude fat 46 % and from N-free extract only 2 %. Minerals and trace elements are consumed in relatively high concentrations compared with recommended allowances determined using empirical methods. The calculated nutrient profile may be considered the nutrient intake to which the cat's metabolic system has adapted. The present study provides insight into the nutritive, as well as possible non-nutritive aspects of a natural diet of whole prey for cats and provides novel ways to further improve feline diets to increase health and longevity.
Farias, Iasmim Baptista de; Morais-Zani, Karen de; Serino-Silva, Caroline; Sant'Anna, Sávio S; Rocha, Marisa M T da; Grego, Kathleen F; Andrade-Silva, Débora; Serrano, Solange M T; Tanaka-Azevedo, Anita M
2018-03-01
Snake venom is a variable phenotypic trait, whose plasticity and evolution are critical for effective antivenom production. A significant reduction of the number of snake donations to Butantan Institute (São Paulo, Brazil) occurred in recent years, and this fact may impair the production of the Brazilian Bothropic Reference Venom (BBRV). Nevertheless, in the last decades a high number of Bothrops jararaca specimens have been raised in captivity in the Laboratory of Herpetology of Butantan Institute. Considering these facts, we compared the biochemical and biological profiles of B. jararaca venom from captive specimens and BBRV in order to understand the potential effects of snake captivity upon the venom composition. Electrophoretic analysis and proteomic profiling revealed few differences in venom protein bands and some differentially abundant toxins. Comparison of enzymatic activities showed minor differences between the two venoms. Similar cross-reactivity recognition pattern of both venoms by the antibothropic antivenom produced by Butantan Institute was observed. Lethality and neutralization of lethality for B. jararaca venom from captive specimens and BBRV showed similar values. Considering these results we suggest that the inclusion of B. jararaca venom from captive specimens in the composition of BBRV would not interfere with the quality of this reference venom. Snakebite envenomation is a neglected tropical pathology whose treatment is based on the use of specific antivenoms. Bothrops jararaca is responsible for the majority of snakebites in South and Southeastern Brazil. Its venom shows individual, sexual, and ontogenetic variability, however, the effect of animal captivity upon venom composition is unknown. Considering the reduced number of wild-caught snakes donated to Butantan Institute in the last decades, and the increased life expectancy of the snakes raised in captivity in the Laboratory of Herpetology, this work focused on the comparative profiling of B. jararaca venom from captive snakes and the Brazilian Bothropic Reference Venom (BBRV). BBRV is composed of venom obtained upon the first milking of wild-caught B. jararaca specimens, and used to assess the potency of all bothropic antivenoms produced by Brazilian suppliers. The use of proteomic strategies, added to biochemical and neutralization tests, allowed to conclude that, despite some subtle differences detected between these two venoms, venom from captive specimens could be used in the BBRV composition without affecting its quality in antivenom potency assays. Copyright © 2017. Published by Elsevier B.V.
Solomons, Noel W; Bailey, Eileen; Soto Méndéz, María José; Campos, Raquel; Kraemer, Klaus; Salem, Norman
2015-07-01
We report the fatty acid composition, and in particular, the n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA), in erythrocytes from a convenience sample of 158 women and 135 schoolchildren residing in the southern Pacific Coast of Guatemala. Erythrocyte fatty acids were analyzed by gas-liquid chromatography with flame ionization detection and the profiles were expressed as a weight percent; the Omega-3 Index values were also determined. Schoolchildren had significantly higher mean ARA and total n-6 fatty acid levels than the women. Women had significantly higher EPA fatty acid levels than schoolchildren, but the reverse was true for DHA. For mean total n-3 fatty acid concentration, women and schoolchildren had similar values. The red cell weight percentages of selected fatty acids were also similar in women and schoolchildren. As compared with erythrocyte fatty acid data from developed countries, Guatemalan women and schoolchildren had consistently lower LCPUFA values. The traditional diet of Guatemalans living in the Pacific coastal region provided a worse erythrocyte fatty acid profile than that typically obtained from a Western diet. Additional fatty acid composition studies with associated dietary intake data in other inland locations may be useful for the interpretation of the nutritional status of Guatemalan children and adults. Copyright © 2015 Elsevier Ltd. All rights reserved.
Rebiere, Hervé; Ghyselinck, Céline; Lempereur, Laurent; Brenier, Charlotte
2016-01-01
The use of performance enhancing drugs is a widespread phenomenon in professional and leisure sports. A spectroscopic study was carried out on anabolic tablets labelled as 5 mg methandienone tablets provided by police departments. The analytical approach was based on a two-step methodology: a fast analysis of tablets using near infrared (NIR) spectroscopy to assess sample homogeneity based on their global composition, followed by Raman chemical imaging of one sample per NIR profile to obtain information on sample formulation. NIR spectroscopy assisted by a principal components analysis (PCA) enabled fast discrimination of different profiles based on the excipient formulation. Raman hyperspectral imaging and multivariate curve resolution - alternating least square (MCR-ALS) provided chemical images of the distribution of the active substance and excipients within tablets and facilitated identification of the active compounds. The combination of NIR spectroscopy and Raman chemical imaging highlighted dose-to-dose variations and succeeded in the discrimination of four different formulations out of eight similar samples of anabolic tablets. Some samples contained either methandienone or methyltestosterone whereas one sample did not contain an active substance. Other ingredients were sucrose, lactose, starch or talc. Both techniques were fast and non-destructive and therefore can be carried out as exploratory methods prior to destructive screening methods. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Peraman, R.; Bhadraya, K.; Reddy, Y. Padmanabha; Reddy, C. Surayaprakash; Lokesh, T.
2015-01-01
By considering the current regulatory requirement for an analytical method development, a reversed phase high performance liquid chromatographic method for routine analysis of etofenamate in dosage form has been optimized using analytical quality by design approach. Unlike routine approach, the present study was initiated with understanding of quality target product profile, analytical target profile and risk assessment for method variables that affect the method response. A liquid chromatography system equipped with a C18 column (250×4.6 mm, 5 μ), a binary pump and photodiode array detector were used in this work. The experiments were conducted based on plan by central composite design, which could save time, reagents and other resources. Sigma Tech software was used to plan and analyses the experimental observations and obtain quadratic process model. The process model was used for predictive solution for retention time. The predicted data from contour diagram for retention time were verified actually and it satisfied with actual experimental data. The optimized method was achieved at 1.2 ml/min flow rate of using mobile phase composition of methanol and 0.2% triethylamine in water at 85:15, % v/v, pH adjusted to 6.5. The method was validated and verified for targeted method performances, robustness and system suitability during method transfer. PMID:26997704
Toporski, Jan; Steele, Andrew
2007-04-01
Morphological, compositional, and biological evidence indicates the presence of numerous well-developed microbial hyphae structures distributed within four different sample splits of the Nakhla meteorite obtained from the British Museum (allocation BM1913,25). By examining depth profiles of the sample splits over time, morphological changes displayed by the structures were documented, as well as changes in their distribution on the samples, observations that indicate growth, decay, and reproduction of individual microorganisms. Biological staining with DNA-specific molecular dyes followed by epifluorescence microscopy showed that the hyphae structures contain DNA. Our observations demonstrate the potential of microbial interaction with extraterrestrial materials, emphasize the need for rapid investigation of Mars return samples as well as any other returned or impactor-delivered extraterrestrial materials, and suggest the identification of appropriate storage conditions that should be followed immediately after samples retrieved from the field are received by a handling/curation facility. The observations are further relevant in planetary protection considerations as they demonstrate that microorganisms may endure and reproduce in extraterrestrial materials over long (at least 4 years) time spans. The combination of microscopy images coupled with compositional and molecular staining techniques is proposed as a valid method for detection of life forms in martian materials as a first-order assessment. Time-resolved in situ observations further allow observation of possible (bio)dynamics within the system.
NASA Technical Reports Server (NTRS)
Douglass, Anne R.; Strahan, Susan E.; Oman, Luke D.; Stolarski, Richard S.
2017-01-01
Constituent evolution for 1990-2015 simulated using the Global Modeling Initiative chemistry and transport model driven by meteorological fields from the Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2) is compared with three sources of observations: ground-based column measurements of HNO3 and HCl from two stations in the Network for the Detection of Atmospheric Composition Change (NDACC, 1990- ongoing), profiles of CH4 from the Halogen Occultation Experiment (HALOE) on the Upper Atmosphere Research Satellite (UARS, 1992-2005), and profiles of N2O from the Microwave Limb Sounder on the Earth Observing System satellite Aura (2005- ongoing). The differences between observed and simulated values are shown to be time dependent, with better agreement after 2000 compared with the prior decade. Furthermore, the differences between observed and simulated HNO3 and HCl columns are shown to be correlated with each other, suggesting that issues with the simulated transport and mixing cause the differences during the 1990s and that these issues are less important during the later years. Because the simulated fields are related to mean age in the lower stratosphere, we use these comparisons to evaluate the time dependence of mean age. The ongoing NDACC column observations provide critical information necessary to substantiate trends in mean age obtained using fields from MERRA-2 or any other reanalysis products.
Shanks, Orin C.; Newton, Ryan J.; Kelty, Catherine A.; Huse, Susan M.; Sogin, Mitchell L.
2013-01-01
Microbial sewage communities consist of a combination of human fecal microorganisms and nonfecal microorganisms, which may be residents of urban sewer infrastructure or flowthrough originating from gray water or rainwater inputs. Together, these different microorganism sources form an identifiable community structure that may serve as a signature for sewage discharges and as candidates for alternative indicators specific for human fecal pollution. However, the structure and variability of this community across geographic space remains uncharacterized. We used massively parallel 454 pyrosequencing of the V6 region in 16S rRNA genes to profile microbial communities from 13 untreated sewage influent samples collected from a wide range of geographic locations in the United States. We obtained a total of 380,175 high-quality sequences for sequence-based clustering, taxonomic analyses, and profile comparisons. The sewage profile included a discernible core human fecal signature made up of several abundant taxonomic groups within Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria. DNA sequences were also classified into fecal, sewage infrastructure (i.e., nonfecal), and transient groups based on data comparisons with fecal samples. Across all sewage samples, an estimated 12.1% of sequences were fecal in origin, while 81.4% were consistently associated with the sewage infrastructure. The composition of feces-derived operational taxonomic units remained congruent across all sewage samples regardless of geographic locale; however, the sewage infrastructure community composition varied among cities, with city latitude best explaining this variation. Together, these results suggest that untreated sewage microbial communities harbor a core group of fecal bacteria across geographically dispersed wastewater sewage lines and that ambient water quality indicators targeting these select core microorganisms may perform well across the United States. PMID:23435885
Simulation of a circular phased array for a portable ultrasonic polar scan
NASA Astrophysics Data System (ADS)
Daemen, Jannes; Kersemans, Mathias; Martens, Arvid; Verboven, Erik; Delrue, Steven; Van Paepegem, Wim; Degrieck, Joris; Van Den Abeele, Koen
2018-04-01
The development of new composite materials, often anisotropic in nature, requires intricate approaches to characterize these materials and to detect internal defects. The Ultrasonic Polar Scan (UPS) is able to achieve both goals. During an UPS experiment, a material spot is insonified at several angles Ψ(θ,ϕ), after which the reflected or transmitted signal is recorded. While excellent results have been obtained using an in-house developed 5-axis scanner, UPS measurements with the current set-up are too lengthy and cumbersome for in-situ industrial application. Therefore, we propose to replace the complex mechanical steering of the transducers by a hemispherical phased array consisting of small PZT elements. This allows to create a compact and portable setup without compromising the current data quality. By successively activating a specific set of elements of the array and choosing appropriate inter-element time delays, the beam can be electronically steered from any angle to a fixed position on the targeted sample. Consequently, UPS reflection measurements can be performed at this position from a wide range of angles in a timeframe of seconds. Additionally, by using apodization windows, it is possible to efficiently reduce the intensity of unwanted side lobes and to create a phase profile which closely resembles that of a bounded plane wave, leading to an easier interpretation of the recorded data. The appropriate time delays and apodization parameters can be found though a multi-objective inverse problem in which both the phase profile and the side lobe reduction are optimized. This approach enables the creation of an effective beam profile to be used during UPS experiments for the characterization and inspection of composite materials. Our simulation approach is a crucial step towards a next-generation UPS device for industrial applications and in-field measurements.
Efficient analysis of complex natural materials using LA-ICP-MS
NASA Astrophysics Data System (ADS)
Kent, A. J.; Loewen, M. W.; Koleszar, A. M.; Miller, J.; Ungerer, C. "
2011-12-01
Many natural materials exhibit complex variations in chemical or isotopic composition over relatively short length scales, and these compositional variations often record important information about the environment or nature of the processes that lead to formation. Examples include complexly zoned crystals within volcanic rocks that record magmatic and volcanic signals, otoliths and other biominerals that record life history and environmental information, and speleothems that record climatic variables. Laser ablation ICP-MS analyses offer several advantages for quantifying compositional in chemically complex natural materials. These include the speed of analysis, the ability to sample at atmospheric pressures, the wide diversity of possible analytes, and the ability to make measurements in both spot and raster modes. The latter in particular offers advantages for analyses that require efficient acquisition of information over significant length scales, as in raster mode compositional data can be rapidly obtained by translating the laser laterally over a compositional variable material during a single analysis. In this fashion elemental or isotopic composition at a given analysis time corresponds to the lateral spatial dimension. This contrasts with a record obtained by a row of individual spots, which require a large number of discrete analyses, and requires significantly more analysis time. However there are also disadvantages to this style of analysis. Translation of the circular spots typically used for analysis results in significant signal attenuation and production of artifacts that may mirror natural diffusion profiles or other gradual changes. The ability to ablate using non-circular spots significantly reduces this effect, although the degree of attenuation is also increased by slower ablation cell response times. For single volume cells this may result in 50-100% additional attenuation than that produced by the translation of the spot alone, although two-volume and other rapid response cells significantly reduce this effect. Raster analyses are also highly sensitive to the presence of small contaminant phases along the raster trajectory, as the compositional signal from these can become attenuated and difficult to distinguish from natural compositional variations. It can also be difficult to establish exactly where compositional changes occur in materials that are visually homogenous. In this contribution we discuss these issues in more detail and present data acquisition and processing strategies that minimize these difficulties.
Analysis of the in vivo confocal Raman spectral variability in human skin
NASA Astrophysics Data System (ADS)
Mogilevych, Borys; dos Santos, Laurita; Rangel, Joao L.; Grancianinov, Karen J. S.; Sousa, Mariane P.; Martin, Airton A.
2015-06-01
Biochemical composition of the skin changes in each layer and, therefore, the skin spectral profile vary with the depth. In this work, in vivo Confocal Raman spectroscopy studies were performed at different skin regions and depth profile (from the surface down to 10 μm) of the stratum corneum, to verify the variability and reproducibility of the intra- and interindividual Raman data. The Raman spectra were collected from seven healthy female study participants using a confocal Raman system from Rivers Diagnostic, with 785 nm excitation line and a CCD detector. Measurements were performed in the volar forearm region, at three different points at different depth, with the step of 2 μm. For each depth point, three spectra were acquired. Data analysis included the descriptive statistics (mean, standard deviation and residual) and Pearson's correlation coefficient calculation. Our results show that inter-individual variability is higher than intraindividual variability, and variability inside the SC is higher than on the skin surface. In all these cases we obtained r values, higher than 0.94, which correspond to high correlation between Raman spectra. It reinforces the possibility of the data reproducibility and direct comparison of in vivo results obtained with different study participants of the same age group and phototype.
Non-LTE spectral analysis and model constraints on SN 1993J
NASA Technical Reports Server (NTRS)
Baron, E.; Hauschildt, P. H.; Branch, D.; Austin, S.; Garnavich, P.; Ann, Hong Bae; Wagner, R. M.; Filippenko, A. V.; Matheson, T.; Liebert, James
1995-01-01
We present non-Local Thermodynamic Equilibrium (LTE) synthetic spectra for a time series of observations of SN 1993J obtained on 1993 March 30-31, April 7, April 13-15, and June 13 UT. The spectra are dominated by hydrogen Balmer lines; neutral helium lines, which have been nonthermally excited; and Fe II features. The density profile evolves from an extremely steep 'brick wall' structure with an equivalent power-law index of about 50 on March 30 to a more typical SN II profile with a power law index of about 10. The early spectra are well fitted by a solar composition of metals, although an enhanced abundance of helium is required in order to fit the neutral helium lines. By June 13, the photosphere has receded deep into the helium layer, although there appears to be a layer of hydrogen at higher velocity. The distance is estimated for each epoch. While consistent results are found for spectra obtained in the month of April, the spread in distances from March to June is quite large. Our value for April is mu = 28.0 +/- 0.3 mag, consistent with the recent Cepheid distance to the host galaxy M81. We also compare our results to other implementations of the expanding photosphere method.
Carrera, Constanza S; Dardanelli, Julio L; Soldini, Diego O
2014-05-01
Information about the chemical profile of soybean seed is valuable for breeding programs aimed at obtaining value-added products to meet the demands of niche markets. The objective of this study was to determine seed composition of non-transgenic soybean genotypes with specialty characters in different environments of Argentina. Protein and oil contents ranged from 396 to 424 g kg⁻¹ and from 210 to 226 g kg⁻¹, respectively. Oleic and linolenic acid ratio, the general indicator of oil quality, varied from 2.7 to 3.8. The oil contained high levels of total tocopherols (1429-1558 mg kg⁻¹) and the meal exhibited high levels of total isoflavones (2.91-4.62 mg g⁻¹). The biplot showed that oleic, linoleic and linolenic acids, γ-, δ- and total tocopherols, genistin, malonyl daidzin and genistin, acetyl daidzin and glycitin and total isoflavones allowed the greatest discrimination among the genotypes studied. Different chemical profiles of each non-transgenic genotype analyzed were established and, therefore, their identity was defined. These results are important for breeders who intend to obtain new genotypes with improved meal and oil quality, as well as for processors and exporters, who could use them directly as raw material for soyfood processing for nutraceutical purposes. © 2013 Society of Chemical Industry.
NASA Astrophysics Data System (ADS)
Kanzaki, Yoshiki; Murakami, Takashi
2018-07-01
We have developed a weathering model to comprehensively understand the determining factors of the apparent activation energy of silicate weathering in order to better estimate the silicate-weathering flux in the Precambrian. The model formulates the reaction rate of a mineral as a basis, then the elemental loss by summing the reaction rates of whole minerals, and finally the weathering flux from a given weathering profile by integrating the elemental losses along the depth of the profile. The rate expressions are formulated with physicochemical parameters relevant to weathering, including solution and atmospheric compositions. The apparent activation energies of silicate weathering are then represented by the temperature dependences of the physicochemical parameters based on the rate expressions. It was found that the interactions between individual mineral-reactions and the compositions of solution and atmosphere are necessarily accompanied by those of temperature-dependence counterparts. Indeed, the model calculates the apparent activation energy of silicate weathering as a function of the temperature dependence of atmospheric CO2 (Δ HCO2‧) . The dependence of the apparent activation energy of silicate weathering on Δ HCO2‧ may explain the empirical dependence of silicate weathering on the atmospheric composition. We further introduce a compensation law between the apparent activation energy and the pre-exponential factor to obtain the relationship between the silicate-weathering flux (FCO2), temperature and the apparent activation energy. The model calculation and the compensation law enable us to predict FCO2 as a function of temperature, once Δ HCO2‧ is given. The validity of the model is supported by agreements between the model prediction and observations of the apparent activation energy and FCO2 in the modern weathering systems. The present weathering model will be useful for the estimation of FCO2 in the Precambrian, for which Δ HCO2‧ can be deduced from the greenhouse effect of atmospheric CO2.
Farag, Mohamed A; Huhman, David V; Lei, Zhentian; Sumner, Lloyd W
2007-02-01
An integrated approach utilizing HPLC-UV-ESI-MS and GC-MS was used for the large-scale and systematic identification of polyphenols in Medicago truncatula root and cell culture. Under optimized conditions, we were able to simultaneously quantify and identify 35 polyphenols including 26 isoflavones, 3 flavones, 2 flavanones, 2 aurones and a chalcone. All identifications were based upon UV spectra, mass spectral characteristics of protonated molecules, tandem mass spectral data, mass measurements obtained using a quadrupole time-of-flight mass spectrometer (QtofMS), and confirmed through the co-characterization of authentic compounds. In specific instances where the stereochemistry of sugar conjugates was uncertain, subsequent enzymatic hydrolysis of the conjugate followed by GC-MS was used to assign the sugar stereochemical configuration. Comparative metabolic profiling of Medicago truncatula root and cell cultures was then performed and revealed significant differences in the isoflavonoid composition of these two tissues.
Blanchard, G; Paragon, B M; Sérougne, C; Férézou, J; Milliat, F; Lutton, C
2004-04-01
Anorexia in obese cats may result in feline hepatic lipidosis (FHL). This study was designed to determine plasma lipids and lipoprotein profiles in queens at different stages during experimental induction of FHL (lean, obese, FHL), and after 10 weeks of treatment. Results were compared with those obtained from lean queens of same age fed the same diet but at a maintenance level, once a day. Hepatic lipidosis led to an increase in plasma triacylglycerol (TG), very low density lipoprotein (VLDL) and low density lipoprotein (LDL), and an enrichment of LDL with TG and of high density lipoprotein (HDL) with cholesterol, suggesting that VLDL secretion is enhanced, VLDL and LDL catabolism is lowered, and lipoprotein exchanges are impaired in FHL. This study also showed that cholesterolaemia is increased in cats fed at a dietary rhythm of one meal per day compared to ad libitum feeding.
High-resolution metabolic mapping of cell types in plant roots
Moussaieff, Arieh; Rogachev, Ilana; Brodsky, Leonid; Malitsky, Sergey; Toal, Ted W.; Belcher, Heather; Yativ, Merav; Brady, Siobhan M.; Benfey, Philip N.; Aharoni, Asaph
2013-01-01
Metabolite composition offers a powerful tool for understanding gene function and regulatory processes. However, metabolomics studies on multicellular organisms have thus far been performed primarily on whole organisms, organs, or cell lines, losing information about individual cell types within a tissue. With the goal of profiling metabolite content in different cell populations within an organ, we used FACS to dissect GFP-marked cells from Arabidopsis roots for metabolomics analysis. Here, we present the metabolic profiles obtained from five GFP-tagged lines representing core cell types in the root. Fifty metabolites were putatively identified, with the most prominent groups being glucosinolates, phenylpropanoids, and dipeptides, the latter of which is not yet explored in roots. The mRNA expression of enzymes or regulators in the corresponding biosynthetic pathways was compared with the relative metabolite abundance. Positive correlations suggest that the rate-limiting steps in biosynthesis of glucosinolates in the root are oxidative modifications of side chains. The current study presents a work flow for metabolomics analyses of cell-type populations. PMID:23476065
Rapid spontaneous Raman light sheet microscopy using cw-lasers and tunable filters
Rocha-Mendoza, Israel; Licea-Rodriguez, Jacob; Marro, Mónica; Olarte, Omar E.; Plata-Sanchez, Marcos; Loza-Alvarez, Pablo
2015-01-01
We perform rapid spontaneous Raman 2D imaging in light-sheet microscopy using continuous wave lasers and interferometric tunable filters. By angularly tuning the filter, the cut-on/off edge transitions are scanned along the excited Stokes wavelengths. This allows obtaining cumulative intensity profiles of the scanned vibrational bands, which are recorded on image stacks; resembling a spectral version of the knife-edge technique to measure intensity profiles. A further differentiation of the stack retrieves the Raman spectra at each pixel of the image which inherits the 3D resolution of the host light sheet system. We demonstrate this technique using solvent solutions and composites of polystyrene beads and lipid droplets immersed in agar and by imaging the C–H (2800-3100cm−1) region in a C. elegans worm. The image acquisition time results in 4 orders of magnitude faster than confocal point scanning Raman systems, allowing the possibility of performing fast spontaneous Raman·3D-imaging on biological samples. PMID:26417514
Experimental Determination of Infrared Extinction Coefficients of Interplanetary Dust Particles
NASA Technical Reports Server (NTRS)
Spann, J. F., Jr.; Abbas, M. M.
1998-01-01
This technique is based on irradiating a single isolated charged dust particle suspended in balance by an electric field, and measuring the scattered radiation as a function of angle. The observed scattered intensity profile at a specific wavelength obtained for a dust particle of known composition is compared with Mie theory calculations, and the variable parameters relating to the particle size and complex refractive index are adjusted for a best fit between the two profiles. This leads to a simultaneous determination of the particle radius, the complex refractive index, and the scattering and extinction coefficients. The results of these experiments can be utilized to examine the IRAS and DIRBE (Diffuse Infrared Background Experiment) infrared data sets in order to determine the dust particle physical characteristics and distributions by using infrared models and inversion techniques. This technique may also be employed for investigation of the rotational bursting phenomena whereby large size cosmic and interplanetary particles are believed to fragment into smaller dust particles.
Evaporation of LOX under supercritical and subcritical conditions
NASA Technical Reports Server (NTRS)
Yang, A. S.; Hsieh, W. H.; Kuo, K. K.; Brown, J. J.
1993-01-01
The evaporation of LOX under supercritical and subcritical conditions was studied experimentally and theoretically. In experiments, the evaporation rate and surface temperature were measured for LOX strand vaporizing in helium environments at pressures ranging from 5 to 68 atmospheres. Gas sampling and chromatography analysis were also employed to profile the gas composition above the LOX surface for the purpose of model validation. A comprehensive theoretical model was formulated and solved numerically to simulate the evaporation process of LOX at high pressures. The model was based on the conservation equations of mass, momentum, energy, and species concentrations for a multicomponent system, with consideration of gravitational body force, solubility of ambient gases in liquid, and variable thermophysical properties. Good agreement between predictions and measured oxygen mole fraction profiles was obtained. The effect of pressure on the distribution of the Lewis number, as well as the effect of variable diffusion coefficient, were further examined to elucidate the high-pressure transport behavior exhibited in the LOX vaporization process.
Perea-Domínguez, Xiomara Patricia; Espinosa-Alonso, Laura Gabriela; Hosseinian, Farah; HadiNezhad, Mehri; Valdez-Morales, Maribel; Medina-Godoy, Sergio
2017-03-01
Jatropha curcas seed shells are the by-product obtained during oil extraction process. Recently, its chemical composition has gained attention since its potential applications. The aim of this study was to identify phenolic compounds profile from a non-toxic J. curcas shell from Mexico, besides, evaluate J. curcas shell methanolic extract (JcSME) antioxidant activity. Free, conjugate and bound phenolics were fractionated and quantified (606.7, 193.32 and 909.59 μg/g shell, respectively) and 13 individual phenolic compounds were detected by HPLC. The radical-scavenging activity of JcSME was similar to Trolox and ascorbic acid by DPPH assay while by ABTS assay it was similar to BHT. Effective antioxidant capacity by ORAC was found (426.44 ± 53.39 μmol Trolox equivalents/g shell). The Mexican non-toxic J. curcas shell is rich in phenolic compounds with high antioxidant activity; hence, it could be considerate as a good source of natural antioxidants.
Berasategi, Izaskun; Navarro-Blasco, Iñigo; Calvo, Maria Isabel; Cavero, Rita Yolanda; Astiasarán, Iciar; Ansorena, Diana
2014-03-01
Reduced-energy and reduced-fat Bologna products enriched with ω-3 polyunsaturated fatty acids were formulated by replacing the pork back-fat by an oil-in-water emulsion containing a mixture of linseed-algae oil stabilized with a lyophilized Melissa officinalis extract. Healthier composition and lipid profile was obtained: 85 kcal/100 g, 3.6% fat, 0.6 g ALA and 0.44 g DHA per 100 g of product and ω-6/ω-3 ratio of 0.4. Technological and sensory problems were not detected in the new formulations. Reformulation did not cause oxidation problems during 32 days of storage under refrigeration. The results suggest that it is possible to obtain reduced-fat Bologna-type sausages rich in ALA and DHA and stabilized with natural antioxidants, applying the appropriate technology without significant effects on the sensory quality, yielding interesting products from a nutritional point of view. © 2013.
Ragazzo-Sánchez, Juan Arturo; Ortiz-Basurto, Rosa Isela; Luna-Solano, Guadalupe; Calderón-Santoyo, Montserrat
2014-01-01
Blackberry (Rubus sp.) juice was fermented using four different strains of Saccharomyces cerevisiae (Vitilevure-CM4457, Enoferm-T306, ICV-K1, and Greroche Rhona-L3574) recognized because of their use in the wine industry. A medium alcoholic graduation spirit (<6°GL) with potential to be produced at an industrial scale was obtained. Alcoholic fermentations were performed at 28°C, 200 rpm, and noncontrolled pH. The synergistic effect on the aromatic compounds production during fermentation in mixed culture was compared with those obtained by monoculture and physic mixture of spirits produced in monoculture. The aromatic composition was determined by HS-SPME-GC. The differences in aromatic profile principally rely on the proportions in aromatic compounds and not on the number of those compounds. The multivariance analysis, principal component analysis (PCA), and factorial discriminant analysis (DFA) permit to demonstrate the synergism between the strains. PMID:25506606
Structural characterization of pharmaceutical heparins prepared from different animal tissues.
Fu, Li; Li, Guoyun; Yang, Bo; Onishi, Akihiro; Li, Lingyun; Sun, Peilong; Zhang, Fuming; Linhardt, Robert J
2013-05-01
Although most pharmaceutical heparin used today is obtained from porcine intestine, heparin has historically been prepared from bovine lung and ovine intestine. There is some regulatory concern about establishing the species origin of heparin. This concern began with the outbreak of mad cow disease in the 1990s and was exacerbated during the heparin shortage in the 2000s and the heparin contamination crisis of 2007-2008. Three heparins from porcine, ovine, and bovine were characterized through state-of-the-art carbohydrate analysis methods with a view profiling their physicochemical properties. Differences in molecular weight, monosaccharide and disaccharide composition, oligosaccharide sequence, and antithrombin III-binding affinity were observed. These data provide some insight into the variability of heparins obtained from these three species and suggest some analytical approaches that may be useful in confirming the species origin of a heparin active pharmaceutical ingredient. Copyright © 2013 Wiley Periodicals, Inc.
Benedetto, Cristina; D'Auria, Maurizio; Mecca, Marisabel; Prasad, Pratti; Singh, Pramod; Singh, Sandeep; Sinisgalli, Chiara; Milella, Luigi
2018-02-19
The purpose of this study is the determination of chemical composition and antioxidant activity of essential oils (EOs) from Saussurea costus (Falc.) Lipsch. Roots have been collected on December of the first plant year (IY) and in April, August and December of the third plant year (I, 6B, D7). A GC analysis was carried out for achieving this purpose. Subsequently, total polyphenol content (TPC) and antioxidant activity measured by DPPH, FRAP and BCB assays were evaluated. Three different statistical methods: Relative Antioxidant Capacity Index (RACI), Pearson's correlation coefficient (r) and PCA, were used to compare results obtained and underline EO relationships. From the results obtained, it was possible to observe how the collection period of the EO, in particular both the month and the year of collection, influences the metabolite profile.
Large scale synthesis of nanostructured zirconia-based compounds from freeze-dried precursors
NASA Astrophysics Data System (ADS)
Gómez, A.; Villanueva, R.; Vie, D.; Murcia-Mascaros, S.; Martínez, E.; Beltrán, A.; Sapiña, F.; Vicent, M.; Sánchez, E.
2013-01-01
Nanocrystalline zirconia powders have been obtained at the multigram scale by thermal decomposition of precursors resulting from the freeze-drying of aqueous acetic solutions. This technique has equally made possible to synthesize a variety of nanostructured yttria or scandia doped zirconia compositions. SEM images, as well as the analysis of the XRD patterns, show the nanoparticulated character of those solids obtained at low temperature, with typical particle size in the 10-15 nm range when prepared at 673 K. The presence of the monoclinic, the tetragonal or both phases depends on the temperature of the thermal treatment, the doping concentration and the nature of the dopant. In addition, Rietveld refinement of the XRD profiles of selected samples allows detecting the coexistence of the tetragonal and the cubic phases for high doping concentration and high thermal treatment temperatures. Raman experiments suggest the presence of both phases also at relatively low treatment temperatures.
Taamalli, Amani; Arráez Román, David; Zarrouk, Mokhtar; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto
2012-05-01
The present work describes a classification method of Tunisian 'Chemlali' olive oils based on their phenolic composition and geographical area. For this purpose, the data obtained by HPLC-ESI-TOF-MS from 13 samples of extra virgin olive oils, obtained from different production area throughout the country, were used for this study focusing in 23 phenolics compounds detected. The quantitative results showed a significant variability among the analysed oil samples. Factor analysis method using principal component was applied to the data in order to reduce the number of factors which explain the variability of the selected compounds. The data matrix constructed was subjected to a canonical discriminant analysis (CDA) in order to classify the oil samples. These results showed that 100% of cross-validated original group cases were correctly classified, which proves the usefulness of the selected variables. Copyright © 2011 Elsevier Ltd. All rights reserved.
Analysis of reflection effects in HS 2333+3927
NASA Astrophysics Data System (ADS)
Shimanskii, V. V.; Yakin, D. G.; Borisov, N. V.; Bikmaev, I. F.
2012-11-01
The results of photometric and spectroscopic observations of the pre-cataclysmic variable HS 2333+3927, which is a HW Vir binary system, are analyzed. The parameters of the sdB subdwarf companion ( T eff = 37 500 ± 500 K, log g = 5.7 ± 0.05) and the chemical composition of its atmosphere are refined using a spectrum of the binary system obtained at minimum brightness. Reflection effects can fully explain the observed brightness variations of HS 2333+3927, changes in the HI and HeI line profiles, and distortions of the radial-velocity curve of the primary star. A new method for determining the component-mass ratios in HW Vir binaries, based on their radial-velocity curves and models of irradiated atmospheres, is proposed. The set of parameters obtained for the binary components corresponds to models of horizontal-branch sdB subdwarfs and main-sequence stars.
Experimental Studies on Mass Transport of Cadmium-Zinc Telluride by Physical Vapor Transport
NASA Technical Reports Server (NTRS)
Palosz, W.; Szofran, F. R.; Lehoczky, S. L.
1995-01-01
Experimental studies on mass transport of ternary compound, Cd(1-x)Zn(x)Te by physical vapor transport (PVT) for source compositions up to X = 0.21 are presented. The effect of thermochemical (temperatures, vapor composition) and other factors (preparation of the source, crystal growth rate, temperature gradient) on composition and composition profiles of the grown crystals were investigated. A steep decrease in the mass flux with an increase in X(crystal) for X less than 0.1, and a difference in composition between the source and the deposited material have been observed. The composition profiles of the crystals were found to depend on the density and pretreatment of the source, and on the temperature gradient in the source zone. The homogeneity of the crystals improves at low undercoolings and/or when an appropriate excess of metal constituents is present in the vapor phase. The experimental results are in good agreement with our thermochemical model of this system.
Profile extrusion and mechanical properties of crosslinked wood–thermoplastic composites
Magnus Bengtsson; Kristiina Oksman; Stark Nicole M.
2006-01-01
Challenges for wood-thermoplastic composites to be utilized in structural applications are to lower product weight and to improve the long-term load performance. Silane crosslinking of the composites is one way to reduce the creep during long-term loading and to improve the mechanical properties. In this study, silane crosslinked wood-polyethylene composites were...
NASA Astrophysics Data System (ADS)
Papayannis, A.; Mamouri, R. E.; Amiridis, V.; Remoundaki, E.; Tsaknakis, G.; Kokkalis, P.; Veselovskii, I.; Kolgotin, A.; Nenes, A.; Fountoukis, C.
2012-05-01
A strong Saharan dust event that occurred over the city of Athens, Greece (37.9° N, 23.6° E) between 27 March and 3 April 2009 was followed by a synergy of three instruments: a 6-wavelength Raman lidar, a CIMEL sun-sky radiometer and the MODIS sensor. The BSC-DREAM model was used to forecast the dust event and to simulate the vertical profiles of the aerosol concentration. Due to mixture of dust particles with low clouds during most of the reported period, the dust event could be followed by the lidar only during the cloud-free day of 2 April 2009. The lidar data obtained were used to retrieve the vertical profile of the optical (extinction and backscatter coefficients) properties of aerosols in the troposphere. The aerosol optical depth (AOD) values derived from the CIMEL ranged from 0.33-0.91 (355 nm) to 0.18-0.60 (532 nm), while the lidar ratio (LR) values retrieved from the Raman lidar ranged within 75-100 sr (355 nm) and 45-75 sr (532 nm). Inside a selected dust layer region, between 1.8 and 3.5 km height, mean LR values were 83 ± 7 and 54 ± 7 sr, at 355 and 532 nm, respectively, while the Ångström-backscatter-related (ABR355/532) and Ångström-extinction-related (AER355/532) were found larger than 1 (1.17 ± 0.08 and 1.11 ± 0.02, respectively), indicating mixing of dust with other particles. Additionally, a retrieval technique representing dust as a mixture of spheres and spheroids was used to derive the mean aerosol microphysical properties (mean and effective radius, number, surface and volume density, and mean refractive index) inside the selected atmospheric layers. Thus, the mean value of the retrieved refractive index was found to be 1.49( ± 0.10) + 0.007( ± 0.007)i, and that of the effective radiuses was 0.30 ± 0.18 μm. The final data set of the aerosol optical and microphysical properties along with the water vapor profiles obtained by Raman lidar were incorporated into the ISORROPIA II model to provide a possible aerosol composition consistent with the retrieved refractive index values. Thus, the inferred chemical properties showed 12-40% of dust content, sulfate composition of 16-60%, and organic carbon content of 15-64%, indicating a possible mixing of dust with haze and smoke. PM10 concentrations levels, PM10 composition results and SEM-EDX (Scanning Electron Microscope-Energy Dispersive X-ray) analysis results on sizes and mineralogy of particles from samples during the Saharan dust transport event were used to evaluate the retrieval.
Yan, H; Lu, H; Almeida, V V; Ward, M G; Adeola, O; Nakatsu, C H; Ajuwon, K M
2017-02-01
In the present study, the effects of dietary resistant starch (RS) content on serum metabolite and hormone concentrations, milk composition, and faecal microbial profiling in lactating sows, as well as on offspring performance was investigated. Sixteen sows were randomly allotted at breeding to two treatments containing low- and high-RS contents from normal and high-amylose corn varieties, respectively, and each treatment had eight replicates (sows). Individual piglet body weight (BW) and litter size were recorded at birth and weaning. Milk samples were obtained on day 10 after farrowing for composition analysis. On day 2 before weaning, blood and faecal samples were collected to determine serum metabolite and hormone concentrations and faecal microbial populations, respectively. Litter size at birth and weaning were not influenced (p > 0.05) by the sow dietary treatments. Although feeding the RS-rich diet to sows reduced (p = 0.004) offspring birth BW, there was no difference in piglet BW at weaning (p > 0.05). High-RS diet increased (p < 0.05) serum triacylglycerol and nonesterified fatty acid concentrations and milk total solid content, and tended (p = 0.09) to increase milk fat content in lactating sows. Feeding the RS-rich diet to sows increased (p < 0.01) faecal bacterial population diversity. These results indicate that high-RS diets induce fatty acid mobilization and a greater intestinal bacterial richness in lactating sows, as well as a greater nutrient density in maternal milk, without affecting offspring performance at weaning. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.
Tang, Zheng-Zheng; Chen, Guanhua; Alekseyenko, Alexander V
2016-09-01
Recent advances in sequencing technology have made it possible to obtain high-throughput data on the composition of microbial communities and to study the effects of dysbiosis on the human host. Analysis of pairwise intersample distances quantifies the association between the microbiome diversity and covariates of interest (e.g. environmental factors, clinical outcomes, treatment groups). In the design of these analyses, multiple choices for distance metrics are available. Most distance-based methods, however, use a single distance and are underpowered if the distance is poorly chosen. In addition, distance-based tests cannot flexibly handle confounding variables, which can result in excessive false-positive findings. We derive presence-weighted UniFrac to complement the existing UniFrac distances for more powerful detection of the variation in species richness. We develop PERMANOVA-S, a new distance-based method that tests the association of microbiome composition with any covariates of interest. PERMANOVA-S improves the commonly-used Permutation Multivariate Analysis of Variance (PERMANOVA) test by allowing flexible confounder adjustments and ensembling multiple distances. We conducted extensive simulation studies to evaluate the performance of different distances under various patterns of association. Our simulation studies demonstrate that the power of the test relies on how well the selected distance captures the nature of the association. The PERMANOVA-S unified test combines multiple distances and achieves good power regardless of the patterns of the underlying association. We demonstrate the usefulness of our approach by reanalyzing several real microbiome datasets. miProfile software is freely available at https://medschool.vanderbilt.edu/tang-lab/software/miProfile z.tang@vanderbilt.edu or g.chen@vanderbilt.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.
Tang, Zheng-Zheng; Chen, Guanhua; Alekseyenko, Alexander V.
2016-01-01
Motivation: Recent advances in sequencing technology have made it possible to obtain high-throughput data on the composition of microbial communities and to study the effects of dysbiosis on the human host. Analysis of pairwise intersample distances quantifies the association between the microbiome diversity and covariates of interest (e.g. environmental factors, clinical outcomes, treatment groups). In the design of these analyses, multiple choices for distance metrics are available. Most distance-based methods, however, use a single distance and are underpowered if the distance is poorly chosen. In addition, distance-based tests cannot flexibly handle confounding variables, which can result in excessive false-positive findings. Results: We derive presence-weighted UniFrac to complement the existing UniFrac distances for more powerful detection of the variation in species richness. We develop PERMANOVA-S, a new distance-based method that tests the association of microbiome composition with any covariates of interest. PERMANOVA-S improves the commonly-used Permutation Multivariate Analysis of Variance (PERMANOVA) test by allowing flexible confounder adjustments and ensembling multiple distances. We conducted extensive simulation studies to evaluate the performance of different distances under various patterns of association. Our simulation studies demonstrate that the power of the test relies on how well the selected distance captures the nature of the association. The PERMANOVA-S unified test combines multiple distances and achieves good power regardless of the patterns of the underlying association. We demonstrate the usefulness of our approach by reanalyzing several real microbiome datasets. Availability and Implementation: miProfile software is freely available at https://medschool.vanderbilt.edu/tang-lab/software/miProfile. Contact: z.tang@vanderbilt.edu or g.chen@vanderbilt.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27197815
An approach to monitor food and nutrition from ‘Factory to Fork.’
Slining, Meghan; Yoon, Emily Ford; Davis, Jessica; Hollingsworth, Bridget; Miles, Donna; Ng, Shu Wen
2014-01-01
Background Accurate, adequate, and timely food and nutrition information is necessary in order to monitor changes in the US food supply and assess their impact on individual dietary intake. Objective Develop an approach that links time-specific purchase and consumption data to provide updated, market representative nutrient information. Data and Methods We utilized household purchase data (Nielsen Homescan, 2007–2008), self-reported dietary intake data [What We Eat in America (WWEIA), 2007–2008], and two sources of nutritional composition data. This factory to fork Crosswalk approach connected each of the items reported to have been obtained from stores from the 2007–2008 cycle of the WWEIA dietary intake survey to corresponding food and beverage products that were purchased by US households during the equivalent time period. Using nutrition composition information and purchase data, an alternate Crosswalk-based nutrient profile for each WWEIA intake code was created weighted by purchase volume of all corresponding items. Mean intakes of daily calories, total sugars, sodium, and saturated fat were estimated. Results Differences were observed in the average daily calories, sodium and total sugars reported consumed from beverages, yogurts and cheeses, depending on whether the FNDDS 4.1 or the alternate nutrient profiles were used. Conclusions The Crosswalk approach augments national nutrition surveys with commercial food and beverage purchases and nutrient databases to capture changes in the US food supply from factory to fork. The Crosswalk provides a comprehensive and representative measurement of the types, amounts, prices, locations and nutrient composition of CPG foods and beverages consumed in the US. This system has potential to be a major step forward in understanding the CPG sector of the US food system and the impacts of the changing food environment on human health. PMID:25441958
Antalick, Guillaume; Šuklje, Katja; Blackman, John W; Meeks, Campbell; Deloire, Alain; Schmidtke, Leigh M
2015-05-13
The relationship between grape composition and subsequent red wine ester profile was examined. Cabernet Sauvignon and Shiraz, from the same Australian very warm climate vineyard, were harvested at two different stages of maturity and triplicate wines were vinified. Grape analyses focused on nitrogen and lipid composition by measuring 18 amino acids by HPLC-FLD, 3 polyunsaturated fatty acids, and 6 C6-compounds derived from lipid degradation by GC-MS. Twenty esters and four higher alcohols were analyzed in wines by HS-SPME-GC-MS. Concentrations of the ethyl esters of branched acids were significantly affected by grape maturity, but the variations were inconsistent between cultivars. Small relative variations were observed between wines for ethyl esters of fatty acids, whereas higher alcohol acetates displayed the most obvious differences with concentrations ranging from 1.5- to 26-fold higher in Shiraz than in Cabernet Sauvignon wines regardless of the grape maturity. Grape analyses revealed the variations of wine ester composition might be related to specific grape juice nitrogen composition and lipid metabolism. To the authors' knowledge the present study is the first to investigate varietal differences in the ester profiles of Shiraz and Cabernet Sauvignon wines made with grapes harvested at different maturity stages.
Asikin, Yonathan; Fukunaga, Hibiki; Yamano, Yoshimasa; Hou, De-Xing; Maeda, Goki; Wada, Koji
2014-09-01
Shiikuwasha (Citrus depressa Hayata) juice from four main cultivation lines subjected to two peeling practices (with or without peeling) were discriminated in terms of quality attributes, represented by sugar and organic acid composition, taste characteristic, aroma profile, and antioxidant activity. Shiikuwasha juice from these lines had diverse food compositions; 'Izumi kugani' juice had lower acidity but contained more ascorbic acid than that of other cultivation lines. The composition of volatile aroma components was influenced by fruit cultivation line, whereas its content was affected by peeling process (20.26-53.73 mg L(-1) in whole juice versus 0.82-1.58 mg L(-1) in flesh juice). Peeling also caused Shiikuwasha juice to be less astringent and acidic bitter and to lose its antioxidant activity. Moreover, the total phenolic and ascorbic acid content of Shiikuwasha juice positively influenced its antioxidant activity. Each fruit cultivation line had a distinct food composition, taste characteristic, and aroma profile. Peeling in Shiikuwasha juice production might reduce aftertaste, and thus might improve its palatability. Comprehensive information on the effect of cultivation line and peeling on quality attributes will be useful for Shiikuwasha juice production, and can be applied to juice production of similar small citrus fruits. © 2014 Society of Chemical Industry.
Ravetto Enri, Simone; Renna, Manuela; Probo, Massimiliano; Lussiana, Carola; Battaglini, Luca M; Lonati, Michele; Lombardi, Giampiero
2017-03-01
Plant composition of species-rich mountain grasslands can affect the sensorial and chemical attributes of dairy and meat products, with implications for human health. A multivariate approach was used to analyse the complex relationships between vegetation characteristics (botanical composition and plant community variables) and chemical composition (proximate constituents and fatty acid profile) in mesophilic and dry vegetation ecological groups, comprising six different semi-natural grassland types in the Western Italian Alps. Mesophilic and dry grasslands were comparable in terms of phenology, biodiversity indices and proportion of botanical families. The content of total fatty acids and that of the most abundant fatty acids (alpha-linolenic, linoleic and palmitic acids) were mainly associated to nutrient-rich plant species, belonging to the mesophilic grassland ecological group. Mesophilic grasslands showed also higher values of crude protein, lower values of fibre content and they were related to higher pastoral values of vegetation compared to dry grasslands. The proximate composition and fatty acid profile appeared mainly single species dependent rather than botanical family dependent. These findings highlight that forage from mesophilic grasslands can provide higher nutritive value for ruminants and may be associated to ruminant-derived food products with a healthier fatty acid profile. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Electrical conductivity of the Earth's mantle after one year of SWARM magnetic field measurements
NASA Astrophysics Data System (ADS)
Civet, François; Thebault, Erwan; Verhoeven, Olivier; Langlais, Benoit; Saturnino, Diana
2015-04-01
We present a global EM induction study using L1b Swarm satellite magnetic field measurements data down to a depth of 2000 km. Starting from raw measurements, we first derive a model for the main magnetic field, correct the data for a lithospheric field model, and further select the data to reduce the contributions of the ionospheric field. These computations allowed us to keep a full control on the data processes. We correct residual field from outliers and estimate the spherical harmonic coefficients of the transient field for periods between 2 and 256 days. We used full latitude range and all local times to keep a maximum amount of data. We perform a Bayesian inversion and construct a Markov chain during which model parameters are randomly updated at each iteration. We first consider regular layers of equal thickness and extra layers are added where conductivity contrast between successive layers exceed a threshold value. The mean and maximum likelihood of the electrical conductivity profile is then estimated from the probability density function. The obtained profile particularly shows a conductivity jump in the 600-700 km depth range, consistent with the olivine phase transition at 660 km depth. Our study is the first one to show such a conductivity increase in this depth range without any a priori informations on the internal strucutres. Assuming a pyrolitic mantle composition, this profile is interpreted in terms of temperature variations in the depth range where the probability density function is the narrowest. We finally obtained a temperature gradient in the lower mantle close to adiabatic.
A Methodology to Seperate and Analyze a Seismic Wide Angle Profile
NASA Astrophysics Data System (ADS)
Weinzierl, Wolfgang; Kopp, Heidrun
2010-05-01
General solutions of inverse problems can often be obtained through the introduction of probability distributions to sample the model space. We present a simple approach of defining an a priori space in a tomographic study and retrieve the velocity-depth posterior distribution by a Monte Carlo method. Utilizing a fitting routine designed for very low statistics to setup and analyze the obtained tomography results, it is possible to statistically separate the velocity-depth model space derived from the inversion of seismic refraction data. An example of a profile acquired in the Lesser Antilles subduction zone reveals the effectiveness of this approach. The resolution analysis of the structural heterogeneity includes a divergence analysis which proves to be capable of dissecting long wide-angle profiles for deep crust and upper mantle studies. The complete information of any parameterised physical system is contained in the a posteriori distribution. Methods for analyzing and displaying key properties of the a posteriori distributions of highly nonlinear inverse problems are therefore essential in the scope of any interpretation. From this study we infer several conclusions concerning the interpretation of the tomographic approach. By calculating a global as well as singular misfits of velocities we are able to map different geological units along a profile. Comparing velocity distributions with the result of a tomographic inversion along the profile we can mimic the subsurface structures in their extent and composition. The possibility of gaining a priori information for seismic refraction analysis by a simple solution to an inverse problem and subsequent resolution of structural heterogeneities through a divergence analysis is a new and simple way of defining a priori space and estimating the a posteriori mean and covariance in singular and general form. The major advantage of a Monte Carlo based approach in our case study is the obtained knowledge of velocity depth distributions. Certainly the decision of where to extract velocity information on the profile for setting up a Monte Carlo ensemble is limiting the a priori space. However, the general conclusion of analyzing the velocity field according to distinct reference distributions gives us the possibility to define the covariance according to any geological unit if we have a priori information on the velocity depth distributions. Using the wide angle data recorded across the Lesser Antilles arc, we are able to resolve a shallow feature like the backstop by a robust and simple divergence analysis. We demonstrate the effectiveness of the new methodology to extract some key features and properties from the inversion results by including information concerning the confidence level of results.
de Carvalho Rocha, Werickson Fortunato; Schantz, Michele M.; Sheen, David A.; Chu, Pamela M.; Lippa, Katrice A.
2017-01-01
As feedstocks transition from conventional oil to unconventional petroleum sources and biomass, it will be necessary to determine whether a particular fuel or fuel blend is suitable for use in engines. Certifying a fuel as safe for use is time-consuming and expensive and must be performed for each new fuel. In principle, suitability of a fuel should be completely determined by its chemical composition. This composition can be probed through use of detailed analytical techniques such as gas chromatography-mass spectroscopy (GC-MS). In traditional analysis, chromatograms would be used to determine the details of the composition. In the approach taken in this paper, the chromatogram is assumed to be entirely representative of the composition of a fuel, and is used directly as the input to an algorithm in order to develop a model that is predictive of a fuel's suitability. When a new fuel is proposed for service, its suitability for any application could then be ascertained by using this model to compare its chromatogram with those of the fuels already known to be suitable for that application. In this paper, we lay the mathematical and informatics groundwork for a predictive model of hydrocarbon properties. The objective of this work was to develop a reliable model for unsupervised classification of the hydrocarbons as a prelude to developing a predictive model of their engine-relevant physical and chemical properties. A set of hydrocarbons including biodiesel fuels, gasoline, highway and marine diesel fuels, and crude oils was collected and GC-MS profiles obtained. These profiles were then analyzed using multi-way principal components analysis (MPCA), principal factors analysis (PARAFAC), and a self-organizing map (SOM), which is a kind of artificial neural network. It was found that, while MPCA and PARAFAC were able to recover descriptive models of the fuels, their linear nature obscured some of the finer physical details due to the widely varying composition of the fuels. The SOM was able to find a descriptive classification model which has the potential for practical recognition and perhaps prediction of fuel properties. PMID:28603295
Martins, Cátia; Brandão, Tiago; Almeida, Adelaide; Rocha, Sílvia M
2015-06-01
The aroma profile of beer is crucial for its quality and consumer acceptance, which is modu-lated by a network of variables. The main goal of this study was to optimize solid-phase microextraction experimental parameters (fiber coating, extraction temperature, and time), taking advantage of the comprehensive two-dimensional gas chromatography structured separation. As far as we know, it is the first time that this approach was used to the untargeted and comprehensive study of the beer volatile profile. Decarbonation is a critical sample preparation step, and two conditions were tested: static and under ultrasonic treatment, and the static condition was selected. Considering the conditions that promoted the highest extraction efficiency, the following parameters were selected: poly(dimethylsiloxane)/divinylbenzene fiber coating, at 40ºC, using 10 min of pre-equilibrium followed by 30 min of extraction. Around 700-800 compounds per sample were detected, corresponding to the beer volatile profile. An exploratory application was performed with commercial beers, using a set of 32 compounds with reported impact on beer aroma, in which different patterns can be observed through the structured chromatogram. In summary, the obtained results emphasize the potential of this methodology to allow an in-depth study of volatile molecular composition of beer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Nunoura, Takuro; Takaki, Yoshihiro; Shimamura, Shigeru; Kakuta, Jungo; Kazama, Hiromi; Hirai, Miho; Masui, Noriaki; Tomaru, Hitoshi; Morono, Yuki; Imachi, Hiroyuki; Inagaki, Fumio; Takai, Ken
2016-06-01
Subseafloor pelagic sediments with high concentrations of organic matter form habitats for diverse microorganisms. Here, we determined depth profiles of genes for SSU rRNA, mcrA, dsrA and amoA from just beneath the seafloor to 363.3 m below the seafloor (mbsf) using core samples obtained from the forearc basin off the Shimokita Peninsula. The molecular profiles were combined with data on lithostratigraphy, depositional age, sedimentation rate and pore-water chemistry. The SSU rRNA gene tag structure and diversity changed at around the sulfate-methane transition zone (SMTZ), whereas the profiles varied further with depth below the SMTZ, probably in connection with the variation in pore-water chemistry. The depth profiles of diversity and abundance of dsrA, a key gene for sulfate reduction, suggested the possible niche separations of sulfate-reducing populations, even below the SMTZ. The diversity and abundance patterns of mcrA, a key gene for methanogenesis/anaerobic methanotrophy, suggested a stratified distribution and separation of anaerobic methanotrophy and hydrogenotrophic or methylotrophic methanogensis below the SMTZ. This study provides novel insights into the relationships between the composition and function of microbial communities and the chemical environment in the nutrient-rich continental margin subseafloor sediments, which may result in niche separation and variability in subseafloor microbial populations. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.
D-region differential-phase measurements and ionization variability studies
NASA Technical Reports Server (NTRS)
Weiland, R. M.; Bowhill, S. A.
1978-01-01
Measurements of electron densities in the D region are made by the partial-reflection differential-absorption and differential-phase techniques. The differential-phase data are obtained by a hard-wired phase-measuring system. Electron-sensity profiles obtained by the two techniques on six occasions are plotted and compared. Electron-density profiles obtained at the same time on 30 occasions during the years 1975 through 1977 are averaged to form a single profile for each technique. The effect of varying the assumed collision-frequency profile on these averaged profiles is studied. Time series of D-region electron-sensity data obtained by 3.4 minute intervals on six days during the summer of 1977 are examined for wave-like disturbances and tidal oscillations.
NASA Astrophysics Data System (ADS)
Kemp, Robert J.
This dissertation examines household energy consumption in the United States over the period of 1987 to 2009, specifically focusing on the role of socioeconomic status, demographic composition, and energy services profiles. The dissertation makes use of four cross-sections from the Residential Energy Consumption Survey data series to examine how household characteristics influence annual energy consumption overall, and by fuel type. Chapter 4 shows that household income is positively related to energy consumption, but more so for combustible fuel consumption than for electricity consumption. Additionally, results for educational attainment suggest a less cross-sectional association and more longitudinal importance as related to income. Demographic composition matters, as predicted by the literature; household size and householder age show predicted effects, but when considered together, income explains any interaction between age and household size. Combustible fuels showed a far greater relationship to housing unit size and income, whereas electricity consumption was more strongly related to educational attainment, showing important differences in the associations by fuel type. Taken together, these results suggest a life course-based model for understanding energy consumption that may be strongly linked to lifestyles. Chapter 5 extends the findings in Chapter 4 by examining the patterning of physical characteristics and behaviors within households. The chapter uses Latent Class Analysis to examine a broad set of energy significant behaviors and characteristics to discover five unique energy services profiles. These profiles are uniquely patterned across demographic and socioeconomic compositions of households and have important effects on energy consumption. These profiles are likely byproducts of the lifestyles in which the household takes part, due to factors such as their socioeconomic status and household demographic composition. Overall, the dissertation finds strong evidence for taking a more lifecycle-based approach to understanding how energy is consumed based on the combined importance of householder age, household size, and socioeconomic status. Additionally, these factors produce very different energy services profiles that I argue are indicative of the lifestyle in which a household engages. Finally, the dissertation argues that these connections are essential to understanding energy consumption and provide a fertile ground for future research.
Fallis, D W; Kusy, R P
2000-11-01
Prototype continuous, unidirectional, fiber-reinforced composite archwires were manufactured into round and rectangular profiles utilizing a photo-pultrusion process. Both 0.022 inch (0.56 mm) diameter and 0.021 x 0.028 inch (0.53 x 0.71 mm) rectangular composites were formed utilizing commercially available S2-glass reinforcement within a polymeric matrix. Reinforcement was varied according to the number, denier and twists per inch (TPI) of four S2-glass yarns to volume levels of 32-74% for round and 41-61% for rectangular profiles. Cross-sectional geometry was evaluated via light microscopy to determine loading characteristics; whereas two flexural properties (the elastic moduli and flexural strengths) were determined by 3-point bending tests. Morphological evaluation of samples revealed that as the TPI increased from 1 to 8, the yarns were more separated from one another and distributed more peripherally within a profile. For round and rectangular profiles utilizing 1 TPI fibers, moduli increased with fiber content approaching theoretical values. For round profiles utilizing 1 TPI and 4 TPI fibers, flexural strengths increased until the loading geometry was optimized. In contrast, the flexural strengths of composites that were pultruded with 8 TPI fibers were not improved at any loading level. Doubling the denier of the yarn, without altering the loading, increased both the moduli and flexural strengths in rectangular samples; whereas, the increases observed in round samples were not statistically significant. At optimal loading the maximum mean moduli and strengths equaled 53.6 +/- 2.0 and 1.36 +/- 0.17 GPa for round wire and equaled 45.7 +/- 0.8 and 1.40 +/- 0.05 GPa for rectangular wires, respectively. These moduli were midway between that of martensitic NiTi (33.4 GPa) and beta-titanium (72.4 GPa), and produced about one-quarter the force of a stainless steel wire per unit of activation. Values of strengths placed this composite material in the range of published values for beta-titanium wires (1.3-1.5 GPa). Copyright 2000 Kluwer Academic Publishers
Composite anode for lithium ion batteries
de Guzman, Rhet C.; Ng, K.Y. Simon; Salley, Steven O.
2018-03-06
A composite anode for a lithium-ion battery is manufactured from silicon nanoparticles having diameters mostly under 10 nm; providing an oxide layer on the silicon nanoparticles; dispersing the silicon nanoparticles in a polar liquid; providing a graphene oxide suspension; mixing the polar liquid containing the dispersed silicone nanoparticles with the graphene oxide suspension to obtain a composite mixture; probe-sonicating the mixture for a predetermined time; filtering the composite mixture to obtain a solid composite; drying the composite; and reducing the composite to obtain graphene and silicon.
Drought and heat stress effects on soybean fatty acid composition and oil stability
USDA-ARS?s Scientific Manuscript database
Previous studies have shown that oil concentration and fatty acid profile (composition) change with genotype, environment (mainly heat and drought), and geographical location. The changes in fatty acid composition under these conditions affect fatty acid stability, creating a challenge to oil proces...
Composition at Washington State University: Building a Multimodal Bricolage
ERIC Educational Resources Information Center
Ericsson, Patricia; Hunter, Leeann Downing; Macklin, Tialitha Michelle; Edwards, Elizabeth Sue
2016-01-01
Multimodal pedagogy is increasingly accepted among composition scholars. However, putting such pedagogy into practice presents significant challenges. In this profile of Washington State University's first-year composition program, we suggest a multi-vocal and multi-theoretical approach to addressing the challenges of multimodal pedagogy. Patricia…
Dawidowicz, Andrzej L; Czapczyńska, Natalia B; Wianowska, Dorota
2013-02-01
Sea Sand Disruption Method (SSDM) is a simple and cheap sample-preparation procedure allowing the reduction of organic solvent consumption, exclusion of sample component degradation, improvement of extraction efficiency and selectivity, and elimination of additional sample clean-up and pre-concentration step before chromatographic analysis. This article deals with the possibility of SSDM application for the differentiation of essential-oils components occurring in the Scots pine (Pinus sylvestris L.) and cypress (Cupressus sempervirens L.) needles from Madrid (Spain), Laganas (Zakhyntos, Greece), Cala Morell (Menorca, Spain), Lublin (Poland), Helsinki (Finland), and Oradea (Romania). The SSDM results are related to the analogous - obtained applying two other sample preparation methods - steam distillation and Pressurized Liquid Extraction (PLE). The results presented established that the total amount and the composition of essential-oil components revealed by SSDM are equivalent or higher than those obtained by one of the most effective extraction technique, PLE. Moreover, SSDM seems to provide the most representative profile of all essential-oil components as no heat is applied. Thus, this environmentally friendly method is suggested to be used as the main extraction procedure for the differentiation of essential-oil components in conifers for scientific and industrial purposes. Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.
SRXRF analysis with spatial resolution of dental calculus
NASA Astrophysics Data System (ADS)
Sánchez, Héctor Jorge; Pérez, Carlos Alberto; Grenón, Miriam
2000-09-01
This work presents elemental-composition studies of dental calculus by X-ray fluorescence analysis using synchrotron radiation. The intrinsic characteristics of synchrotron light allow for a semi-quantitative analysis with spatial resolution. The experiments were carried out in the high-vacuum station of the XRF beamline at the Synchrotron Light National Laboratory (Campinas, Brazil). All the measurements were performed in conventional geometry (45°+45°) and the micro-collimation was attained via a pair of orthogonal slits mounted in the beamline. In this way, pixels of 50 μm×50 μm were obtained keeping a high flux of photons on the sample. Samples of human dental calculus were measured in different positions along their growing axis, in order to determine variations of the compositions in the pattern of deposit. Intensity ratios of minor elements and traces were obtained, and linear profiles and surface distributions were determined. As a general summary, we can conclude that μXRF experiments with spatial resolution on dental calculus are feasible with simple collimation and adequate positioning systems, keeping a high flux of photon. These results open interesting perspectives for the future station of the line, devoted to μXRF, which will reach resolutions of the order of 10 μm.
Brahmi, Faten; Chehab, Hechmi; Flamini, Guido; Dhibi, Madiha; Issaoui, Manel; Mastouri, Maha; Hammami, Mohamed
2013-11-15
The olive tree is generally grown under rain-fed conditions. However, since the yield response to irrigation is great, even with low amounts of water, there is increasing interest in irrigated agriculture. The main goal of this study was, therefore, to investigate the effect of irrigation regimes on olive (Olea europaea L., cv. Koroneiki) obtained from an intensively-managed orchard in a semi-arid area with a Mediterranean climate in Tunisia. Different irrigation treatments 50% ETc, 75% ETc and 100% ETc were applied to the olive orchard. Accordingly, the effects of three irrigation regimes on volatile compounds, fatty acid composition and biological activities of Koroneiki cultivar were studied. The total profile of the volatile constituents of all samples revealed the predominance of 3-ethenylpyridine (from 14.9-19.6%), phenylethyl alcool (from 7.8-19.2%) and benzaldehyde (from 9.0 to 13.8%). During watering level treatments studied, the major fatty acids were oleic, palmitic and linoleic. Antioxidant activity of the fresh fruit volatiles cultivated at a watering level of 100% ETc was higher than that obtained under 50 and 75% Etc. The results of antifungal activity showed that the fruits volatiles of the three irrigation treatments had varying degrees of growth inhibition against the microorganisms tested.
Enhanced dissolution of sildenafil citrate as dry foam tablets.
Sawatdee, Somchai; Atipairin, Apichart; Sae Yoon, Attawadee; Srichana, Teerapol; Changsan, Narumon
2017-01-30
Dry foam formulation technology is alternative approach to enhance dissolution of the drug. Sildenafil citrate was suspended in sodium dodecyl sulfate solution and adding a mixture of maltodextrin and mannitol as diluent to form a paste. Sildenafil citrate paste was passed through a nozzle spray bottle to obtain smooth foam. The homogeneous foam was dried in a vacuum oven and sieved to obtain dry foam granules. The granules were mixed with croscarmellose sodium, magnesium stearate and compressed into tablet. All formulations were evaluated for their physicochemical properties and dissolution profiles. All the tested excipients were compatible with sildenafil citrate by both differential scanning calorimetry (DSC) and infrared (IR) analysis. There are no X-ray diffraction (XRD) peaks representing crystals of sildenafil citrate observed form dry foam formulations. The hardness of tablets was about 5 kg, friability test <1% with a disintegration time <5 min. The sildenafil citrate dry foam tablet had higher dissolution rate in 0.1 N HCl in comparison with commercial sildenafil citrate tablet, sildenafil citrate prepared by direct compression and wet granulation method. Sildenafil citrate dry foam tablet with the high-level composition of surfactant, water and diluent showed enhanced dissolution rate than that of the lower-level composition of these excipients. This formulation was stable under accelerated conditions for at least 6 months.
MALINA: a web service for visual analytics of human gut microbiota whole-genome metagenomic reads.
Tyakht, Alexander V; Popenko, Anna S; Belenikin, Maxim S; Altukhov, Ilya A; Pavlenko, Alexander V; Kostryukova, Elena S; Selezneva, Oksana V; Larin, Andrei K; Karpova, Irina Y; Alexeev, Dmitry G
2012-12-07
MALINA is a web service for bioinformatic analysis of whole-genome metagenomic data obtained from human gut microbiota sequencing. As input data, it accepts metagenomic reads of various sequencing technologies, including long reads (such as Sanger and 454 sequencing) and next-generation (including SOLiD and Illumina). It is the first metagenomic web service that is capable of processing SOLiD color-space reads, to authors' knowledge. The web service allows phylogenetic and functional profiling of metagenomic samples using coverage depth resulting from the alignment of the reads to the catalogue of reference sequences which are built into the pipeline and contain prevalent microbial genomes and genes of human gut microbiota. The obtained metagenomic composition vectors are processed by the statistical analysis and visualization module containing methods for clustering, dimension reduction and group comparison. Additionally, the MALINA database includes vectors of bacterial and functional composition for human gut microbiota samples from a large number of existing studies allowing their comparative analysis together with user samples, namely datasets from Russian Metagenome project, MetaHIT and Human Microbiome Project (downloaded from http://hmpdacc.org). MALINA is made freely available on the web at http://malina.metagenome.ru. The website is implemented in JavaScript (using Ext JS), Microsoft .NET Framework, MS SQL, Python, with all major browsers supported.
Asymmetrical flow field-flow fractionation of white wine chromophoric colloidal matter.
Coelho, Christian; Parot, Jérémie; Gonsior, Michael; Nikolantonaki, Maria; Schmitt-Kopplin, Philippe; Parlanti, Edith; Gougeon, Régis D
2017-04-01
Two analytical separation methods-size-exclusion chromatography and asymmetrical flow field-flow fractionation-were implemented to evaluate the integrity of the colloidal composition of Chardonnay white wine and the impact of pressing and fermentations on the final macromolecular composition. Wine chromophoric colloidal matter, representing UV-visible-absorbing wine macromolecules, was evaluated by optical and structural measurements combined with the description of elution profiles obtained by both separative techniques. The objective of this study was to apply these two types of fractionation on a typical Chardonnay white wine produced in Burgundy and to evaluate how each of them impacted the determination of the macromolecular chromophoric content of wine. UV-visible and fluorescence measurements of collected fractions were successfully applied. An additional proteomic study revealed that grape and microorganism proteins largely impacted the composition of chromophoric colloidal matter of Chardonnay wines. Asymmetrical flow field-flow fractionation appeared to be more reliable and less invasive with respect to the native chemical environment of chromophoric wine macromolecules, and hence is recommended as a tool to fractionate chromophoric colloidal matter in white wines. Graphical Abstract An innovative macromolecular separation method based on Asymmetrical Flow Field-Flow Fractionation was developed to better control colloidal dynamics across Chardonnay white winemaking.
NASA Astrophysics Data System (ADS)
Chatterjee, A. K.; Banerjee, R.; Sharon, M.
The electrochemical characteristics of a porous ceramic that is coated with carbon beads, impregnated with Ni, Fe and Co catalyst and operated as a hydrogen electrode for an alkaline fuel cell (AFC) are studied. To improve the catalytic activity and electrode performance, Ni is bimetallized with Co as well as Fe. Chemical vapour deposition (CVD) of turpentine oil, a renewable natural precursor, is used to grow the carbon beads. Various compositions of Ni-Co and Ni-Fe (10:90, 50:50, 90:10) are electroplated over the carbon-coated ceramic substrate. The detailed surface profile and elemental composition of the electrodes are studied by SEM, TEM, XRD and XRF analysis. Vander-Pauw resistivity measurements of the electrodes showed an increase in the conductivity of Ni electrode by addition of Co and Fe. The electrochemical performance is investigated by measuring hydrogen dissociation voltage, half-cell and full-cell current-potential characteristics and chrono-potentiometry in 30% KOH solution. The activity of the NI electrode is improved by addition of small amounts of Co and Fe. The best performance is obtained using an electrode coated with 90:10 ratios of Ni-Co and Ni-Fe bimetallic composition.
Aab, A.; Abreu, P.; Aglietta, M.; ...
2014-12-01
Using the data taken at the Pierre Auger Observatory between December 2004 and December 2012, we have examined the implications of the distributions of depths of atmospheric shower maximum (Xmax), using a hybrid technique, for composition and hadronic interaction models. We do this by fitting the distributions with predictions from a variety of hadronic interaction models for variations in the composition of the primary cosmic rays and examining the quality of the fit. Regardless of what interaction model is assumed, we find that our data are not well described by a mix of protons and iron nuclei over most ofmore » the energy range. Acceptable fits can be obtained when intermediate masses are included, and when this is done consistent results for the proton and iron-nuclei contributions can be found using the available models. We observe a strong energy dependence of the resulting proton fractions, and find no support from any of the models for a significant contribution from iron nuclei. However, we also observe a significant disagreement between the models with respect to the relative contributions of the intermediate components.« less
Ho-Plágaro, Tania; Huertas, Raúl; Tamayo-Navarrete, María I; Ocampo, Juan A; García-Garrido, José M
2018-01-01
Solanum lycopersicum , an economically important crop grown worldwide, has been used as a model for the study of arbuscular mycorrhizal (AM) symbiosis in non-legume plants for several years and several cDNA array hybridization studies have revealed specific transcriptomic profiles of mycorrhizal tomato roots. However, a method to easily screen candidate genes which could play an important role during tomato mycorrhization is required. We have developed an optimized procedure for composite tomato plant obtaining achieved through Agrobacterium rhizogenes -mediated transformation. This protocol involves the unusual in vitro culture of composite plants between two filter papers placed on the culture media. In addition, we show that DsRed is an appropriate molecular marker for the precise selection of cotransformed tomato hairy roots . S. lycopersicum composite plant hairy roots appear to be colonized by the AM fungus Rhizophagus irregularis in a manner similar to that of normal roots, and a modified construct useful for localizing the expression of promoters putatively associated with mycorrhization was developed and tested. In this study, we present an easy, fast and low-cost procedure to study AM symbiosis in tomato roots.
NASA Astrophysics Data System (ADS)
Semeniuk, Christina A. D.; Speers-Roesch, Ben; Rothley, Kristina D.
2007-10-01
Feeding marine wildlife as a tourism experience has become a popular means by which to attract both people and wildlife, although management efforts are still in their infancy. “Stingray City Sandbar” in the Cayman Islands, where visitors can hand feed free-ranging Southern Stingrays ( Dasyatis americana), is a world-famous attraction currently undergoing visitor and wildlife management. One plan is to decrease the amount of nonnatural food provided by tourists with the intention of decreasing stingray habituation to the artificial food source and promoting stingray health. However, the effectiveness of this action is uncertain given that neither the extent of squid composition in the stingray diet nor the degree of nutrient similarity between the fed and natural diets is unknown. We used fatty acid (FA) profile analysis to address these questions by assessing the serum nonesterified FA composition of fed and unfed stingrays around the island and compared them with FA profiles of (1) the provisioned food source (squid) and (2) other warm- and cold-water elasmobranchs (sharks and rays). Our results indicated that fed stingrays were distinct. The FA profiles of the fed stingray population were expressly different from those of the unfed populations and showed a remarkable similarity to the FA composition of squid, suggesting that squid is the main food source. The tropical fed stingrays also exhibited essential FA ratios, specific to both species and habitat, comparable with those of elasmobranchs and squid from cold-water environs, implying that the provisioned food does not provide a similar nutritional lipid composition to that eaten in the wild. Our results suggest that FA profiles are a valuable indicator for the management and monitoring of fed Southern Stingrays because they can be used to assess differences in diet composition and provide an index of nutritional similarity. Our findings are currently being used by Caymanian stakeholders in designing practical management actions for their wildlife attraction.
Taghadomi-Saberi, Saeedeh; Mas Garcia, Sílvia; Allah Masoumi, Amin; Sadeghi, Morteza; Marco, Santiago
2018-06-13
The quality and composition of bitter orange essential oils (EOs) strongly depend on the ripening stage of the citrus fruit. The concentration of volatile compounds and consequently its organoleptic perception varies. While this can be detected by trained humans, we propose an objective approach for assessing the bitter orange from the volatile composition of their EO. The method is based on the combined use of headspace gas chromatography⁻mass spectrometry (HS-GC-MS) and artificial neural networks (ANN) for predictive modeling. Data obtained from the analysis of HS-GC-MS were preprocessed to select relevant peaks in the total ion chromatogram as input features for ANN. Results showed that key volatile compounds have enough predictive power to accurately classify the EO, according to their ripening stage for different applications. A sensitivity analysis detected the key compounds to identify the ripening stage. This study provides a novel strategy for the quality control of bitter orange EO without subjective methods.
New Horizons Observations of the Atmospheres of Pluto and Charon
NASA Astrophysics Data System (ADS)
Gladstone, G. R.; Stern, S. A.; Weaver, H. A.; Young, L. A.; Ennico, K. A.; Olkin, C. B.; Cheng, A. F.; Greathouse, T. K.; Hinson, D. P.; Kammer, J. A.; Linscott, I. R.; Parker, A. H.; Parker, J. Wm.; Retherford, K. D.; Schindhelm, E.; Singer, K. N.; Steffl, A. J.; Strobel, D. F.; Summers, M. E.; Tsang, C. C. C.; Tyler, G. L.; Versteeg, M. H.; Woods, W. W.; Cunningham, N.; Curdt, W.
2015-11-01
Major goals of the New Horizons (NH) mission are to explore and characterize the structure and composition of Pluto’s atmosphere, and to establish whether Charon has a measurable atmosphere of its own. The primary instruments onboard NH which contribute to these goals are the REX instrument, through uplink X-band radio occultations, the Alice instrument, through extreme- and far-ultraviolet solar occultations, and the LORRI panchromatic imager, through high-phase-angle imaging. The associated datasets were obtained following closest approach of NH to Pluto. Pressure and temperature profiles of the lower atmosphere are derived from the REX data, the composition and structure of the extended atmosphere are derived from the Alice data (supported by approach observations of reflected ultraviolet sunlight), and the distribution and properties of Pluto’s hazes are derived from the LORRI data. In this talk an overview of the early atmosphere science results will be presented.This work was supported by NASA's New Horizons project.
In Vitro Cultivars of Vaccinium corymbosum L. (Ericaceae) are a Source of Antioxidant Phenolics.
Contreras, Rodrigo A; Köhler, Hans; Pizarro, Marisol; Zúiga, Gustavo E
2015-04-09
The antioxidant activity and phenolic composition of six in vitro cultured blueberry seedlings were determined. Extracts were prepared in 85% ethanol from 30 days old in vitro cultured plants and used to evaluate the antioxidant capacities that included Ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazin (DPPH•) scavenging ability, total polyphenols (TP) and the partial phenolic composition performed by high performance liquid chromatography with diode array detector (HPLC-DAD), liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS (ESI-QqQ)). All ethanolic extracts from in vitro blueberry cultivars displayed antioxidant activity, with Legacy, Elliott and Bluegold cultivars being the most active. In addition, we observed a positive correlation between phenolic content and antioxidant activity. Our results suggest that the antioxidant activity of the extracts is related to the content of chlorogenic acid myricetin, syringic acid and rutin, and tissue culture of blueberry seedlings is a good tool to obtain antioxidant extracts with reproducible profile of compounds.
NASA Astrophysics Data System (ADS)
Damle, R. M.; Ardhapurkar, P. M.; Atrey, M. D.
2016-12-01
In J-T cryocoolers operating with mixed refrigerants (nitrogen-hydrocarbons), the recuperative heat exchange takes place under two-phase conditions. Simultaneous boiling of the low pressure stream and condensation of the high pressure stream results in higher heat transfer coefficients. The mixture composition, operating conditions and the heat exchanger design are crucial for obtaining the required cryogenic temperature. In this work, a one-dimensional transient algorithm is developed for the simulation of the two-phase heat transfer in the recuperative heat exchanger of a mixed refrigerant J-T cryocooler. Modified correlation is used for flow boiling of the high pressure fluid while different condensation correlations are employed with and without the correction for the low pressure fluid. Simulations are carried out for different mixture compositions and numerical predictions are compared with the experimental data. The overall heat transfer is predicted reasonably well and the qualitative trends of the temperature profiles are also captured by the developed numerical model.
Micro-electrolysis of Cr (VI) in the nanoscale zero-valent iron loaded activated carbon.
Wu, Limei; Liao, Libing; Lv, Guocheng; Qin, Faxiang; He, Yujuan; Wang, Xiaoyu
2013-06-15
In this paper we prepared a novel material of activated carbon/nanoscale zero-valent iron (C-Fe(0)) composite. The C-Fe(0) was proved to possess large specific surface area and outstanding reducibility that result in the rapid and stable reaction with Cr (VI). The prepared composite has been examined in detail in terms of the influence of solution pH, concentration and reaction time in the Cr (VI) removal experiments. The results showed that the C-Fe(0) formed a micro-electrolysis which dominated the reaction rate. The Micro-electrolysis reaches equilibrium is ten minutes. Its reaction rate is ten times higher than that of traditional adsorption reaction, and the removal rate of Cr reaches up to 99.5%. By analyzing the obtained profiles from the cyclic voltammetry, PXRD and XPS, we demonstrate that the Cr (VI) is reduced to insoluble Cr (III) compound in the reaction. Copyright © 2013 Elsevier B.V. All rights reserved.
Essential oil composition of stems and fruits of Caralluma europaea N.E.Br. (Apocynaceae).
Zito, Pietro; Sajeva, Maurizio; Bruno, Maurizio; Maggio, Antonella; Rosselli, Sergio; Formisano, Carmen; Senatore, Felice
2010-01-27
The essential oil of the stems and fruits of Caralluma europaea (Guss.) N.E.Br. (Apocynaceae) from Lampedusa Island has been obtained by hydrodistillation and its composition analyzed. The analyses allowed the identification and quantification of 74 volatile compounds, of which 16 were aromatic and 58 non-aromatic. Stems and fruits contained 1.4% and 2.7% of aromatic compounds respectively, while non-aromatic were 88.3% and 88.8%. Non-aromatic hydrocarbons were the most abundant compounds in both organs, followed by fatty acids. Data showed differences in the profiles between stems and fruits which shared only eighteen compounds; stems accounted for 38 compounds while fruits for 53. Fruits showed a higher diversity especially in aromatic compounds with twelve versus four in stems. Among the volatiles identified in stems and fruits of C. europaea 26 are present in other taxa of Apocynaceae, 52 are semiochemicals for many insects, and 21 have antimicrobial activity. The possible ecological role of the volatiles found is briefly discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Avilov, V. I.; Ageev, O. A.; Konoplev, B. G.
2016-05-15
The results of experimental studies of the phase composition of oxide nanostructures formed by the local anodic oxidation of a titanium thin film are reported. The data of the phase analysis of titanium-oxide nanostructures are obtained by X-ray photoelectron spectroscopy in the ion profiling mode of measurements. It is established that the surface of titanium-oxide nanostructures 4.5 ± 0.2 nm in height possesses a binding energy of core levels characteristic of TiO{sub 2} (458.4 eV). By analyzing the titanium-oxide nanostructures in depth by X-ray photoelectron spectroscopy, the formation of phases with binding energies of core levels characteristic of Ti{sub 2}O{submore » 3} (456.6 eV) and TiO (454.8 eV) is established. The results can be used in developing the technological processes of the formation of a future electronic-component base for nanoelectronics on the basis of titanium-oxide nanostructures and probe nanotechnologies.« less
NASA Technical Reports Server (NTRS)
Wurzbach, J. A.; Grunthaner, F. J.
1983-01-01
It is pointed out that there is no report of an unambiguous analysis of the composition and interfacial structure of MNOS (metal-nitride oxide semiconductor) systems, despite the technological importance of these systems. The present investigation is concerned with a study of an MNOS structure on the basis of a technique involving the use of X-ray photoelectron spectroscopy (XPS) with a controlled stopped-flow chemical-etching procedure. XPS is sensitive to the structure of surface layers, while stopped-flow etching permits the controlled removal of overlying material on a scale of atomic layers, to expose new surface layers as a function of thickness. Therefore, with careful analysis of observed intensities at measured depths, this combination of techniques provides depth resolution between 5 and 10 A. According to the obtained data there is intact SiO2 at the substrate interface. There appears to be a thin layer containing excess bonds to silicon on top of the SiO2.
In Vitro Cultivars of Vaccinium corymbosum L. (Ericaceae) are a Source of Antioxidant Phenolics
Contreras, Rodrigo A.; Köhler, Hans; Pizarro, Marisol; Zúñiga, Gustavo E.
2015-01-01
The antioxidant activity and phenolic composition of six in vitro cultured blueberry seedlings were determined. Extracts were prepared in 85% ethanol from 30 days old in vitro cultured plants and used to evaluate the antioxidant capacities that included Ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazin (DPPH•) scavenging ability, total polyphenols (TP) and the partial phenolic composition performed by high performance liquid chromatography with diode array detector (HPLC-DAD), liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS (ESI-QqQ)). All ethanolic extracts from in vitro blueberry cultivars displayed antioxidant activity, with Legacy, Elliott and Bluegold cultivars being the most active. In addition, we observed a positive correlation between phenolic content and antioxidant activity. Our results suggest that the antioxidant activity of the extracts is related to the content of chlorogenic acid myricetin, syringic acid and rutin, and tissue culture of blueberry seedlings is a good tool to obtain antioxidant extracts with reproducible profile of compounds. PMID:26783705
NASA Astrophysics Data System (ADS)
Freire, F. L., Jr.; Senna, L. F.; Achete, C. A.; Hirsch, T.
1998-03-01
Hard TiCN films were deposited by dc-magnetron sputter-ion plating technique onto high-speed carbon steel S-6-5-2 (M 2). For selected deposition conditions, TiCN films were also deposited onto Si substrates. A Ti target was sputtered in ArCH 4N 2 atmosphere. The argon flux (12 sccm) was fixed and corresponds to 90% of the total flux, whereas the N 2 flux ranged from 3% to 9% of the total flux. The total pressure in the chamber during film deposition was 8-9 × 10 -2Pa. The substrate bias, Vb, was between 0 and -140V and the substrate temperature, Ts, was 350°C. Film composition and depth profile of the elements were obtained by Rutherford backscattering spectrometry (RBS) and glow discharge optical spectroscopy (GDOS). Some limitations of both techniques in analysing TiCN films were presented. The effect of methane poisoing of the Ti target and how it influences the film composition was discussed.
Comparisons of Airborne HSRL and Modeled Aerosol Profiles
NASA Astrophysics Data System (ADS)
Ferrare, R. A.; Burton, S. P.; Hostetler, C. A.; Hair, J. W.; Ismail, S.; Rogers, R. R.; Notari, A.; Berkoff, T.; Butler, C. F.; Collins, J. E., Jr.; Fenn, M. A.; Scarino, A. J.; Clayton, M.; Mueller, D.; Chemyakin, E.; Fast, J. D.; Berg, L. K.; Randles, C. A.; Colarco, P. R.; daSilva, A.
2014-12-01
Aerosol profiles derived from a regional and a global model are compared with aerosol profiles acquired by NASA Langley Research Center (LaRC) airborne High Spectral Resolution Lidars (HSRLs) during recent field missions. We compare simulated aerosol profiles obtained from the WRF-Chem regional model with those measured by the airborne HSRL-2 instrument over the Atlantic Ocean east of Cape Cod in July 2012 during the Department of Energy Two-Column Aerosol Project (TCAP). While deployed on the LaRC King Air during TCAP, HSRL-2 acquired profiles of aerosol extinction at 355 and 532 nm, as well as aerosol backscatter and depolarization at 355, 532, and 1064 nm. Additional HSRL-2 data products include profiles of aerosol type, mixed layer depth, and aerosol microphysical parameters (e.g. effective radius, concentration). The HSRL-2 and WRF-Chem aerosol profiles are compared along the aircraft flight tracks. HSRL-2 profiles acquired during the NASA Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) mission over Houston during September 2013 are compared with the NASA Goddard Earth Observing System global model, version 5 (GEOS-5) profiles. In addition to comparing backscatter and extinction profiles, the fraction of aerosol extinction and optical thickness from various aerosol species from GEOS-5 are compared with aerosol extinction and optical thickness contributed by aerosol types derived from HSRL-2 data. We also compare aerosol profiles modeled by GEOS-5 with those measured by the airborne LaRC DIAL/HSRL instrument during August and September 2013 when it was deployed on the NASA DC-8 for the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) mission. DIAL/HSRL measured extinction (532 nm), backscatter (532 and 1064 nm), and depolarization profiles (532 and 1064 nm) in both nadir and zenith directions during long transects over the continental United States. DIAL/HSRL measurements acquired during SEAC4RS allow comparisons with GEOS-5 simulations of forest fire smoke over the western U.S. The fraction of aerosol extinction attributed to dust derived from the DIAL/HSRL depolarization measurements are compared with the corresponding GEOS-5 dust simulations.
Ghachem, Ahmed; Prud'homme, Denis; Rabasa-Lhoret, Rémi; Brochu, Martin
2017-08-01
To compare the effects of a caloric restriction (CR) on body composition, lipid profile, and glucose homeostasis in obese postmenopausal women with and without metabolic syndrome (MetS). Secondary analyses were performed on 73 inactive obese postmenopausal women (age 57.7 ± 4.8 years; body mass index 32.4 ± 4.6 kg/m) who participated in the 6-month CR arm of a study of the Montreal-Ottawa New Emerging Team. The harmonized MetS definition was used to categorize participants with MetS (n = 20, 27.39%) and without MetS (n = 53, 72.61%). Variables of interest were: body composition (dual-energy X-ray absorptiometry), body fat distribution (computed tomography scan), glucose homeostasis at fasting state and during a euglycemic/hyperinsulinemic clamp, fasting lipids, and resting blood pressure. By design, the MetS group had a worse cardiometabolic profile, whereas both groups were comparable for age. Fifty-five participants out of 73 displayed no change in MetS status after the intervention. Twelve participants out of 20 (or 60.0%) in the MetS group had no more MetS after weight loss (P = NS), whereas 6 participants out of 53 (or 11.3%) in the other group developed the MetS after the intervention (P = NS). Overall, indices of body composition and body fat distribution improved significantly and similarly in both groups (P between 0.03 and 0.0001). Furthermore, with the exception of triglyceride levels and triglycerides/high-density lipoprotein cholesterol ratio, which decrease significantly more in the MetS group (P ≤ 0.05), no difference was observed between groups for the other variables of the cardiometabolic profile. Despite no overall significant effects on MetS, heteregeneous results were obtained in response to weight loss in the present study, with some improving the MetS, whereas other displaying deteriorations. Further studies are needed to identify factors and phenotypes associated with positive and negative cardiometabolic responses to CR intervention.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Won, Yoo Jai; Ki, Hyungson
A novel picosecond-laser pulsed laser deposition method has been developed for fabricating functionally graded films with pre-designed gradient profiles. Theoretically, the developed method is capable of precisely fabricating films with any thicknesses and any gradient profiles by controlling the laser beam powers for the two different targets based on the film composition profiles. As an implementation example, we have successfully constructed functionally graded diamond-like carbon films with six different gradient profiles: linear, quadratic, cubic, square root, cubic root, and sinusoidal. Energy dispersive X-ray spectroscopy is employed for investigating the chemical composition along the thickness of the film, and the depositionmore » profile and thickness errors are found to be less than 3% and 1.04%, respectively. To the best of the authors' knowledge, this is the first method for fabricating films with designed gradient profiles and has huge potential in many areas of coatings and films, including multifunctional optical films. We believe that this method is not only limited to the example considered in this study, but also can be applied to all material combinations as long as they can be deposited using the pulsed laser deposition technique.« less
Durability and mechanical properties of silane cross-linked wood thermoplastic composites
Magnus Bengtsson; Nicole M. Stark; Kristiina Oksman
2007-01-01
In this study, silane cross-linked woodâpolyethylene composite profiles were manufactured by reactive extrusion. These composites were evaluated regarding their durability and mechanical properties in comparison with two non-cross-linked woodâ polyethylene composites. An addition of only 2% w/w of silane solution during manufacturing was enough to achieve almost 60%...
Na/K-interdiffusion in alkali feldspar: new data on diffusion anisotropy and composition dependence
NASA Astrophysics Data System (ADS)
Schaeffer, Anne-Kathrin; Petrishcheva, Elena; Habler, Gerlinde; Abart, Rainer; Rhede, Dieter
2013-04-01
Exchange experiments between gem-quality alkali feldspar with an initial XOr of 0.85 or 0.72 and Na/K-salt melts have been conducted at temperatures between 800° and 1000° C. The crystals were prepared as crystallographically oriented plates, the polished surfaces corresponding to the (010) or (001) plane of the feldspar. The composition of the melts was varied systematically to induce a controlled shift of the feldspar towards more Na-rich or K-rich compositions (XOr 0.5 to 1). A molar excess of cations by a factor of 40 in the melt ensured constant concentration boundary conditions for cation exchange. Different geometries of diffusion profiles can be observed depending on the direction of the composition shift. For a shift towards more K-rich compositions the diffusion profile exhibits two plateaus corresponding to an exchanged rim in equilibrium with the melt and a completely unexchanged core, respectively. Between these plateaus an exchange front develops with an inflection point that progresses into the crystal with t1-2. The width of this diffusion front varies greatly with the extent of chemical shift and crystallographic direction. The narrowest profiles are always found in the direction normal to (010), i.e. b, marking the slowest direction of interdiffusion. A shift towards more Na-rich composition leads to the development of a crack system due to the composition strain associated with the substitution of the larger K+ion with the smaller Na+ion. The exchange front developing in this case lacks the inflection point observed for shifts towards more K-rich compositions. The observed geometry of the diffusion fronts can be explained by a composition dependence of the interdiffusion coefficient. We used the Boltzmann transformation to calculate the interdiffusion coefficient in dependence of composition from our data in a range between XOr 0.5 and 1 for profiles normal to both (010) and (001) and for different temperatures. As indicated by the different widths of the front a marked anisotropy in interdiffusion is apparent; it is about 10 times faster perpendicular to (001) than normal to (010). This is in good accordance with results of earlier studies. However, the composition dependence deviates from what is expected from theoretical calculations using the Manning relation for interdiffusion. For profiles normal to (001) the interdiffusion coefficient is nearly constant at 0.3 x 10-15m2s-1over the composition range XOr 0.50 to 0.95 and then rises steeply to values of 2.5 x 10-15m2s-1. Normal to (010) the interdiffusion coefficient is nearly constant at 0.03 x 10-15m2s-1over the composition range XOr 0.50 to 0.97 before, too, rising steeply at higher XOr. Interdiffusion coefficients calculated by Christoffersen et al. (1983) for this composition range also showed this rise but much less localized and steep. The activation energy also shows an anisotropy and slight composition dependence. Normal to (001) it is about 340 kJ/mole while it is 250 kJ/mole normal to (010). In the range between XOr0.94 to 1 it shows a slight rise by about 20 kJ/mole for both directions. ___ References Christoffersen et al. (1983): Interdiffusion of K and Na in alkali feldspar: diffusion couple experiments, -American Mineralogist, Vol. 68, pp. 1126-1133
Ibrahim, Reham S; Fathy, Hoda
2018-03-30
Tracking the impact of commonly applied post-harvesting and industrial processing practices on the compositional integrity of ginger rhizome was implemented in this work. Untargeted metabolite profiling was performed using digitally-enhanced HPTLC method where the chromatographic fingerprints were extracted using ImageJ software then analysed with multivariate Principal Component Analysis (PCA) for pattern recognition. A targeted approach was applied using a new, validated, simple and fast HPTLC image analysis method for simultaneous quantification of the officially recognized markers 6-, 8-, 10-gingerol and 6-shogaol in conjunction with chemometric Hierarchical Clustering Analysis (HCA). The results of both targeted and untargeted metabolite profiling revealed that peeling, drying in addition to storage employed during processing have a great influence on ginger chemo-profile, the different forms of processed ginger shouldn't be used interchangeably. Moreover, it deemed necessary to consider the holistic metabolic profile for comprehensive evaluation of ginger during processing. Copyright © 2018. Published by Elsevier B.V.
The atmosphere of Neptune - Results of radio occultation measurements with the Voyager 2 spacecraft
NASA Technical Reports Server (NTRS)
Lindal, G. F.; Lyons, J. R.; Sweetnam, D. N.; Eshleman, V. R.; Hinson, D. P.
1990-01-01
This paper presents the vertical temperature and composition profiles of Neptune's troposphere and stratosphere, covering an altitude of 250 km, obtained from radio tracking data that were acquired during Voyager-2's occultation by Neptune, which began near 62 deg N planetographic latitude and ended near 45 deg S latitude. In the computations, the He/H2 abundance ratio 15/85 was adapted, which is consistent with solar abundance estimates and with recent results from Uranus. It was assumed that aerosols and heavier gases such as CH4, NH3, H2S, and H2O have a negligible effect on the microwave refractivity above the 0.5 bar pressure level.
Van Driest transformation and compressible wall-bounded flows
NASA Technical Reports Server (NTRS)
Huang, P. G.; Coleman, G. N.
1994-01-01
The transformation validity question utilizing resulting data from direct numerical simulations (DNS) of supersonic, isothermal cold wall channel flow was investigated. The DNS results stood for a wide scope of parameter and were suitable for the purpose of examining the generality of Van Driest transformation. The Van Driest law of the wall can be obtained from the inner-layer similarity arguments. It was demonstrated that the Van Driest transformation cannot be incorporated to collapse the sublayer and log-layer velocity profiles simultaneously. Velocity and temperature predictions according to the preceding composite mixing-length model were presented. Despite satisfactory congruity with the DNS data, the model must be perceived as an engineering guide and not as a rigorous analysis.
Stellar occultation studies of the solar system
NASA Technical Reports Server (NTRS)
Elliot, J. L.
1979-01-01
The paper covers the principles, observational procedures, and results relating to occultations of stars by solar system bodies other than the moon. Physical processes involved in occultations are presented including (1) extinction by ring material, (2) differential refraction by a planetary atmosphere, (3) extinction by a planetary atmosphere, and (4) Fresnel diffraction by sharp edges. It is noted that from a sufficient number of immersion and emersion timings of a stellar occultation, the radius and ellipticity of the occulting body can be accurately determined. From an occultation by a planet having an atmosphere, temperature, pressure, and number density profiles can be obtained along with information about the composition of the atmosphere and the extinction.
A 2 Thz Schottky Solid-State Heterodyne Receiver for Atmospheric Studies
NASA Technical Reports Server (NTRS)
Treuttel, Jeanne; Schlecht, Erich; Siles, Jose; Lee, Choonsup; Lin, Robert; Thomas, Bertrand; Gonzalez-Olvero, David; Yee, Jeng-Hwa; Wu, Dong; Mehdi, Imran
2016-01-01
Obtaining temperature, pressure, and composition profiles along with wind velocities in the Earth's thermosphere/ionosphere system is a key NASA goal for understanding our planet. We report on the status of a technology development effort to build an all-solid-state heterodyne receiver at 2.06 terahertz that will allow the measurement of the 2.06 terahertz [OI] line for altitudes greater than 100 kilometers. The receiver front end features low-parasitic Schottky diode mixer chips that are driven by a local oscillator (LO) source using Schottky diode based multipliers. The multiplier chain consists of a 38 gigahertz oscillator followed by a set of three cascaded triplers at 114 gigahertz, 343 gigahertz and 1.03 terahertz.
Spectroscopic evidence supporting the gravitational lens hypothesis for 1635+267 A,B
NASA Technical Reports Server (NTRS)
Turner, Edwin L.; Hillenbrand, Lynne A.; Schneider, Donald P.; Hewitt, Jacqueline N.; Burke, Bernard F.
1988-01-01
The gravitational lens hypothesis is tested for 1613+267 A,B by comparing the detailed line widths and shapes of the 2799-A Mg II and semiforbidden 1909-A C-III lines in each component. Following subtraction of an interpolating polynomial fit to the continua and the determination of a single optimum scaling factor (an amplification ratio of 2.83), reasonable agreement between the profiles of both lines in the two composites is obtained. Comparison of these lines to those in an unrelated quasar with a similar redshift and apparent magnitude does not produce a good match. It is suggested that the observed match in the 1635+267 A,B spectra arises from gravitational lensing.