Science.gov

Sample records for transformer admittance characterization

  1. Analytical admittance characterization of high mobility channel

    SciTech Connect

    Mammeri, A. M.; Mahi, F. Z.; Varani, L.

    2015-03-30

    In this contribution, we investigate the small-signal admittance of the high electron mobility transistors field-effect channels under a continuation branching of the current between channel and gate by using an analytical model. The analytical approach takes into account the linearization of the 2D Poisson equation and the drift current along the channel. The analytical equations discuss the frequency dependence of the admittance at source and drain terminals on the geometrical transistor parameters.

  2. Characterizing the eardrum admittance: Comparisons of tympanometry and reflectance

    NASA Astrophysics Data System (ADS)

    Robinson, Sarah; Thompson, Suzanne; Allen, Jont B.

    2015-12-01

    The residual ear canal (REC) between the probe and tympanic membrane (TM) is a significant source of non-pathological variability for acoustic measurements made in the ear canal. Tympanometry and reflectance, which seek to characterize the middle ear based on the TM admittance, must account for unknown REC dimensions. In tympanometry, the REC volume and 226 Hz TM admittance are estimated by varying the canal static pressure. Using a reflectance parametrization developed by the authors, typical assumptions for removing the REC effect are extended, and methods to estimate the REC volume and TM admittance are presented and compared to tympanometry. Results of this method are shown for reflectance measurements of human ears with varying static middle ear pressures (MEPs). The data show that the 226 Hz TM compliance is non-zero at tympanometric pressure extremes, and that acoustic parameters of the middle ear have highly variable, nonlinear dependence on the MEP level.

  3. Electrical admittance of piezoelectric parallelepipeds: application to tensorial characterization of piezoceramics

    NASA Astrophysics Data System (ADS)

    Diallo, O.; Clezio, E. Le; Delaunay, T.; Bavencoffe, M.; Feuillard, G.

    2014-01-01

    This work deals with the characterization of functional properties, including determination of mechanical and electrical losses, of piezoelectric materials using only one sample and one measurement. First, the natural resonant frequencies of a piezoelectric parallelepiped are calculated and the electrical admittance is determined from calculations of the charge quantity on both electrodes of the parallelepiped. A first validation of the model is performed using a comparison with Mason's model. Results are reported for a PMN-34.5PT ceramic cube and a good agreement is found between experimental admittance measurements and their modeling. The functional properties of the PMN-34.5PT are then extracted.

  4. Electrical admittance of piezoelectric parallelepipeds: application to tensorial characterization of piezoceramics

    SciTech Connect

    Diallo, O.; Bavencoffe, M.; Feuillard, G.; Clezio, E. Le; Delaunay, T.

    2014-01-15

    This work deals with the characterization of functional properties, including determination of mechanical and electrical losses, of piezoelectric materials using only one sample and one measurement. First, the natural resonant frequencies of a piezoelectric parallelepiped are calculated and the electrical admittance is determined from calculations of the charge quantity on both electrodes of the parallelepiped. A first validation of the model is performed using a comparison with Mason's model. Results are reported for a PMN-34.5PT ceramic cube and a good agreement is found between experimental admittance measurements and their modeling. The functional properties of the PMN-34.5PT are then extracted.

  5. Feasibility of anomaly detection and characterization using trans-admittance mammography with 60 × 60 electrode array

    NASA Astrophysics Data System (ADS)

    Zhao, Mingkang; Wi, Hun; Lee, Eun Jung; Woo, Eung Je; In Oh, Tong

    2014-10-01

    Electrical impedance imaging has the potential to detect an early stage of breast cancer due to higher admittivity values compared with those of normal breast tissues. The tumor size and extent of axillary lymph node involvement are important parameters to evaluate the breast cancer survival rate. Additionally, the anomaly characterization is required to distinguish a malignant tumor from a benign tumor. In order to overcome the limitation of breast cancer detection using impedance measurement probes, we developed the high density trans-admittance mammography (TAM) system with 60 × 60 electrode array and produced trans-admittance maps obtained at several frequency pairs. We applied the anomaly detection algorithm to the high density TAM system for estimating the volume and position of breast tumor. We tested four different sizes of anomaly with three different conductivity contrasts at four different depths. From multifrequency trans-admittance maps, we can readily observe the transversal position and estimate its volume and depth. Specially, the depth estimated values were obtained accurately, which were independent to the size and conductivity contrast when applying the new formula using Laplacian of trans-admittance map. The volume estimation was dependent on the conductivity contrast between anomaly and background in the breast phantom. We characterized two testing anomalies using frequency difference trans-admittance data to eliminate the dependency of anomaly position and size. We confirmed the anomaly detection and characterization algorithm with the high density TAM system on bovine breast tissue. Both results showed the feasibility of detecting the size and position of anomaly and tissue characterization for screening the breast cancer.

  6. Dynamic characterization of partially saturated engineered porous media and gas diffusion layers using hydraulic admittance

    NASA Astrophysics Data System (ADS)

    Cheung, Perry; Fairweather, Joseph D.; Schwartz, Daniel T.

    2012-09-01

    Simple laboratory methods for determining liquid water distribution in polymer electrolyte membrane fuel cell gas diffusion layers (GDLs) are needed to engineer better GDL materials. Capillary pressure vs. liquid saturation measurements are attractive, but lack the ability to probe the hydraulic interconnectivity and distribution within the pore structure. Hydraulic admittance measurements of simple capillary bundles have recently been shown to nicely measure characteristics of the free-interfaces and hydraulic path. Here we examine the use of hydraulic admittance with a succession of increasingly complex porous media, starting with a laser-drilled sample with 154 asymmetric pores and progress to the behavior of Toray TGP-H090 carbon papers. The asymmetric laser-drilled sample clearly shows hydraulic admittance measurements are sensitive to sample orientation, especially when examined as a function of saturation state. Finite element modeling of the hydraulic admittance is consistent with experimental measurements. The hydraulic admittance spectra from GDL samples are complex, so we examine trends in the spectra as a function of wet proofing (0% and 40% Teflon loadings) as well as saturation state of the GDL. The presence of clear peaks in the admittance spectra for both GDL samples suggests a few pore types are largely responsible for transporting liquid water.

  7. Tevatron admittance measurement

    SciTech Connect

    Zhang, X.L.; Shiltsev, V.; Tan, C.Y.; /Fermilab

    2005-05-01

    We measured the Tevatron beam admittance by the means of exciting the beam with noise and causing emittance growth. The noise power was about 3W with a bandwidth of 100Hz and centered either in the horizontal betatron frequency or vertical betatron frequency. We were able to controllably blow the beam emittance up quickly. From the point where the beam emittance stopped growing, we measured the beam acceptance of the Tevatron.

  8. A new estimate of the effective elastic thickness of the Canadian shield from admittance analyses using the wavelet transform, and models of flexure and mantle convection

    NASA Astrophysics Data System (ADS)

    Kirby, J. F.; Swain, C. J.

    2013-12-01

    The flexural rigidity of the Earth's cratonic regions is a topic of much controversy. While many studies have suggested that cratons possess high elastic strength, others maintain that the continental lithosphere is everywhere weak. In this study we focus on the Canadian shield, and show that perceived evidence for weak cratonic lithosphere is compromised by shortcomings of the spectral analysis technique. Here we compare estimates of the admittance between free-air gravity and topography in the spectral domain from wavelet and multitaper methods. We apply particular attention to their long wavelength values, since it is here that the signals from mantle convection, glacial isostatic adjustment (GIA) and flexure are often present together. Our results show that, when used with certain parameter values, the multitaper method has a comparatively poor resolution at long wavelengths, and hence is not always able to distinguish between the harmonics due to convection and flexural processes. This renders it unreliable for estimating the flexural rigidity. We then show that the wavelet method does have the requisite properties to make this distinction, since it is able to correctly resolve a low-admittance dip at long wavelengths in both synthetic and real data. When the observed wavelet admittance of the Canadian shield is inverted against the predictions of a combined flexural, convection and GIA model, we find that the shield possesses a core of high effective elastic thickness (Te), greater than 118 km to 95% confidence, located to the immediate south-west of Hudson Bay.

  9. Acoustic-Liner Admittance in a Duct

    NASA Technical Reports Server (NTRS)

    Watson, W. R.

    1986-01-01

    Method calculates admittance from easily obtainable values. New method for calculating acoustic-liner admittance in rectangular duct with grazing flow based on finite-element discretization of acoustic field and reposing of unknown admittance value as linear eigenvalue problem on admittance value. Problem solved by Gaussian elimination. Unlike existing methods, present method extendable to mean flows with two-dimensional boundary layers as well. In presence of shear, results of method compared well with results of Runge-Kutta integration technique.

  10. Reservoir characterization using wavelet transforms

    NASA Astrophysics Data System (ADS)

    Rivera Vega, Nestor

    Automated detection of geological boundaries and determination of cyclic events controlling deposition can facilitate stratigraphic analysis and reservoir characterization. This study applies the wavelet transformation, a recent advance in signal analysis techniques, to interpret cyclicity, determine its controlling factors, and detect zone boundaries. We tested the cyclostratigraphic assessments using well log and core data from a well in a fluvio-eolian sequence in the Ormskirk Sandstone, Irish Sea. The boundary detection technique was tested using log data from 10 wells in the Apiay field, Colombia. We processed the wavelet coefficients for each zone of the Ormskirk Formation and determined the wavelengths of the strongest cyclicities. Comparing these periodicities with Milankovitch cycles, we found a strong correspondence of the two. This suggests that climate exercised an important control on depositional cyclicity, as had been concluded in previous studies of the Ormskirk Sandstone. The wavelet coefficients from the log data in the Apiay field were combined to form features. These vectors were used in conjunction with pattern recognition techniques to perform detection in 7 boundaries. For the upper two units, the boundary was detected within 10 feet of their actual depth, in 90% of the wells. The mean detection performance in the Apiay field is 50%. We compared our method with other traditional techniques which do not focus on selecting optimal features for boundary identification. Those methods resulted in detection performances of 40% for the uppermost boundary, which lag behind the 90% performance of our method. Automated determination of geologic boundaries will expedite studies, and knowledge of the controlling deposition factors will enhance stratigraphic and reservoir characterization models. We expect that automated boundary detection and cyclicity analysis will prove to be valuable and time-saving methods for establishing correlations and their

  11. Multi-port admittance model for quantifying the scattering response of loaded plasmonic nanorod antennas.

    PubMed

    Panaretos, Anastasios H; Werner, Douglas H

    2015-02-23

    In this paper we demonstrate the feasibility of using multiport network theory to describe the admittance properties of a longitudinally loaded plasmonic nanorod antenna. Our analysis reveals that if the appropriate terminal ports are defined across the nanorod geometry then the corresponding voltage and current quantities can be probed and thus it becomes feasible to extract the admittance matrix of the structure. Furthermore, it is demonstrated that by utilizing cylindrical dielectric waveguide theory, closed form expressions can be derived that uniquely characterize the loading material in terms of its admittance. The combination of the admittance matrix information along with the load admittance expressions provides an effective methodology for computing the nanorod's input admittance/impedance for arbitrary loading scenarios. This is important because the admittance resonances are associated with the structure's scattering peaks which are excited by a plane wave polarized parallel to its long dimension. Subsequently, the proposed approach provides a fast and computationally efficient circuit-based methodology to predict and custom engineer the scattering properties of a loaded plasmonic nanorod without having to rely on repetitive lengthy full wave simulations. PMID:25836483

  12. Applications of Admittance Spectroscopy in Photovoltaic Devices Beyond Majority Carrier Trapping Defects: Preprint

    SciTech Connect

    Li, J. V.; Crandall, R. S.; Repins, I. L.; Nardes, A. M.; Levi, D. H.; Sulima, O.

    2011-07-01

    Admittance spectroscopy is commonly used to characterize majority-carrier trapping defects. In today's practical photovoltaic devices, however, a number of other physical mechanisms may contribute to the admittance measurement and interfere with the data interpretation. Such challenges arise due to the violation of basic assumptions of conventional admittance spectroscopy such as single-junction, ohmic contact, highly conductive absorbers, and measurement in reverse bias. We exploit such violations to devise admittance spectroscopy-based methods for studying the respective origins of 'interference': majority-carrier mobility, non-ohmic contact potential barrier, minority-carrier inversion at hetero-interface, and minority-carrier lifetime in a device environment. These methods are applied to a variety of photovoltaic technologies: CdTe, Cu(In,Ga)Se2, Si HIT cells, and organic photovoltaic materials.

  13. Characterization of interface defects in ALD Al2O3/p-GaSb MOS capacitors using admittance measurements in range from kHz to GHz

    NASA Astrophysics Data System (ADS)

    Gu, Siyuan; Min, Jie; Taur, Yuan; Asbeck, Peter M.

    2016-04-01

    Atomic layer deposited (ALD) Al2O3/p-type GaSb Metal-Oxide-Semiconductor (MOS) capacitors are studied with capacitance-voltage (C-V) and conductance-voltage (G-V) measurements using AC signal frequencies covering the range from kHz to GHz. The potential and limitations of the measurements at GHz frequencies for oxide and interface defect characterization are described. The effect of bulk oxide traps in communication with the GaSb valence band via hole tunneling is highlighted. Modeling indicates that the C-V and G-V frequency dispersions observed in the accumulation, flat-band and depletion regions of the Al2O3/p-GaSb MOS capacitors are due to combined contributions of bulk-oxide traps and interface traps.

  14. Structures that Contribute to Middle-Ear Admittance in Chinchilla

    PubMed Central

    Rosowski, John J.; Ravicz, Michael E.; Songer, Jocelyn E.

    2009-01-01

    We describe measurements of middle-ear input admittance in chinchillas (Chinchilla lanigera) before and after various manipulations that define the contributions of different middle-ear components to function. The chinchilla’s middle-ear air spaces have a large effect on the low-frequency compliance of the middle ear, and removing the influences of these spaces reveals a highly admittant tympanic membrane and ossicular chain. Measurements of the admittance of the air spaces reveal that the high-degree of segmentation of these spaces has only a small effect on the admittance. Draining the cochlea further increases the middle-ear admittance at low frequencies and removes a low-frequency (less than 300 Hz) level dependence in the admittance. Spontaneous or sound-driven contractions of the middle-ear muscles in deeply anesthetized animals were associated with significant changes in middle-ear admittance. PMID:16944166

  15. A creatinine biosensor based on admittance measurement

    NASA Astrophysics Data System (ADS)

    Ching, Congo Tak-Shing; Sun, Tai-Ping; Jheng, Deng-Yun; Tsai, Hou-Wei; Shieh, Hsiu-Li

    2015-08-01

    Regular check of blood creatinine level is very important as it is a measurement of renal function. Therefore, the objective of this study is to develop a simple and reliable creatinine biosensor based on admittance measurement for precise determination of creatinine. The creatinine biosensor was fabricated with creatinine deiminase immobilized on screen-printed carbon electrodes. Admittance measurement at a specific frequency ranges (22.80 - 84.71 Hz) showed that the biosensor has an excellent linear (r2 > 0.95) response range (50 - 250 uM), which covers the normal physiological and pathological ranges of blood creatinine levels. Intraclass correlation coefficient (ICC) showed that the biosensor has excellent reliability and validity (ICC = 0.98). In conclusion, a simple and reliable creatinine biosensor was developed and it is capable of precisely determining blood creatinine levels in both the normal physiological and pathological ranges.

  16. Computer code for the prediction of nozzle admittance

    NASA Technical Reports Server (NTRS)

    Nguyen, Thong V.

    1988-01-01

    A procedure which can accurately characterize injector designs for large thrust (0.5 to 1.5 million pounds), high pressure (500 to 3000 psia) LOX/hydrocarbon engines is currently under development. In this procedure, a rectangular cross-sectional combustion chamber is to be used to simulate the lower traverse frequency modes of the large scale chamber. The chamber will be sized so that the first width mode of the rectangular chamber corresponds to the first tangential mode of the full-scale chamber. Test data to be obtained from the rectangular chamber will be used to assess the full scale engine stability. This requires the development of combustion stability models for rectangular chambers. As part of the combustion stability model development, a computer code, NOAD based on existing theory was developed to calculate the nozzle admittances for both rectangular and axisymmetric nozzles. This code is detailed.

  17. Experimental determination of three dimensional liquid rocket nozzle admittances.

    NASA Technical Reports Server (NTRS)

    Zinn, B. T.; Bell, W. A.; Daniel, B. R.; Smith, A. J., Jr.

    1972-01-01

    The three dimensional nozzle admittance, an important parameter in combustion instability studies, was experimentally measured for several nozzle configurations. The admittance values were obtained using a modification of the classical impedance tube technique. The modified impedance tube method measures the admittance of a duct termination in the presence of one dimensional mean flow and three dimensional oscillations. Values of the nozzle admittance were obtained from pressure amplitude measurements taken at discrete points along the length of the tube. To determine the effects of nozzle geometry, nozzles were tested with half-angles of 15, 30, and 45 degrees and entrance Mach numbers of 0.08, 0.16, and 0.20. The admittance results are presented as functions of nondimensional frequency for mixed first tangential-longitudinal modes. These results are compared with available theoretical predictions and favorable agreement between theory and experiment is shown.

  18. Coulometric differential FFT admittance voltammetry determination of Amlodipine in pharmaceutical formulation by nano-composite electrode.

    PubMed

    Norouzi, Parviz; Gupta, Vinod Kumar; Larijani, Bagher; Rasoolipour, Solmaz; Faridbod, Farnoush; Ganjali, Mohammad R

    2015-01-01

    An electrochemical detection technique based on combination of was coulometric differential fast Fourier transformation admittance voltammetry (CDFFTAV) and nano-composite film modified glassy carbon electrode was successfully applied for sensitive determination of Amlodipine. The nano-composite film was made by a mixture of ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4), multiwall carbon nanotube and Au nanoparticles as electrochemical mediators. Studies reveal that the irreversible oxidation of Amlodipine was highly facile on the electrode surface. The electrochemical response was established on calculation of the charge under the admittance peak, which was obtained by discrete integration of the admittance response in a selected potential range, obtained in a flow injection analysis. Once established the best operative optimum conditions, the resulting nano-composite film electrode showed a catalytic effect on the oxidation of the analyte. The response is linear in the Amlodipine concentration range of 1.0 × 10(-9) to 2.0 × 10(-7)M with a detection limit of 1.25 × 10(-10)M. Moreover, the proposed technique exhibited high sensitivity, fast response time (less than 6s) and long-term stability and reproducibility around 96%, and it was successfully used to the determination of Amlodipine content in the pharmaceutical formulation. PMID:25281143

  19. Admittance spectroscopy of copper indium diselenide/cadmium sulfide solar cells

    NASA Astrophysics Data System (ADS)

    Strifler, Walter A.

    This dissertation concentrates on admittance spectroscopy of CuInSe2/CdS heterojunction solar cells prepared by chemical spray pyrolysis (CSP) and by multiple-source evaporation (MSE). The primary goal is to examine some of the more important electrical characteristics of these heterojunctions and determine if the spray-pyrolyzed cells behave similar, albeit at a lower efficiency, to higher quality cells prepared by other techniques. The primary analytical tool used in this study is admittance spectroscopy. The theory of admittance spectroscopy is developed using the concept of equivalent circuits. The traditional temperature-swept technique for admittance spectroscopy is shown to be inadequate for measuring most heterojunction samples examined in this study because of the large parallel leakage conductance found in these devices. Instead, a frequency-swept admittance technique is developed and employed to correct for the parallel conductance effect and reveal the true nature of slow charge in the depletion layer. In addition to admittance spectroscopy, the two sets of solar cell diodes are characterized using a variety of measurement techniques including capacitance-voltage, current-voltage over spectral response, capacitance dispersion over wavelength, and solar efficiency. The different pieces of experimental data are discussed to form a self-consistent physical model of the polycrystalline solar cells. Charge transport across the diode junction is dominated by recombination processes within the CuInSe2 depletion layer for both sets of diodes although the large parallel conductance in the CSP diodes often masks this characteristic. The CSP solar cells exhibit a pronounced blue peak in the spectral response indicating that electron collection is the limiting factor in the overall short-circuit quantum efficiency. A large degree of capacitance dispersion is found in both sets of diodes. Supporting measurements indicate that the majority of this dispersion is due

  20. Temperature admittance spectroscopy of boron doped chemical vapor deposition diamond

    NASA Astrophysics Data System (ADS)

    Zubkov, V. I.; Kucherova, O. V.; Bogdanov, S. A.; Zubkova, A. V.; Butler, J. E.; Ilyin, V. A.; Afanas'ev, A. V.; Vikharev, A. L.

    2015-10-01

    Precision admittance spectroscopy measurements over wide temperature and frequency ranges were carried out for chemical vapor deposition epitaxial diamond samples doped with various concentrations of boron. It was found that the experimentally detected boron activation energy in the samples decreased from 314 meV down to 101 meV with an increase of B/C ratio from 600 to 18000 ppm in the gas reactants. For the heavily doped samples, a transition from thermally activated valence band conduction to hopping within the impurity band (with apparent activation energy 20 meV) was detected at temperatures 120-150 K. Numerical simulation was used to estimate the impurity DOS broadening. Accurate determination of continuously altering activation energy, which takes place during the transformation of conduction mechanisms, was proposed by numerical differentiation of the Arrhenius plot. With increase of boron doping level the gradual decreasing of capture cross section from 3 × 10-13 down to 2 × 10-17 cm2 was noticed. Moreover, for the hopping conduction the capture cross section becomes 4 orders of magnitude less (˜2 × 10-20 cm2). At T > Troom in doped samples the birth of the second conductance peak was observed. We attribute it to a defect, related to the boron doping of the material.

  1. Temperature admittance spectroscopy of boron doped chemical vapor deposition diamond

    SciTech Connect

    Zubkov, V. I. Kucherova, O. V.; Zubkova, A. V.; Ilyin, V. A.; Afanas'ev, A. V.; Bogdanov, S. A.; Vikharev, A. L.; Butler, J. E.

    2015-10-14

    Precision admittance spectroscopy measurements over wide temperature and frequency ranges were carried out for chemical vapor deposition epitaxial diamond samples doped with various concentrations of boron. It was found that the experimentally detected boron activation energy in the samples decreased from 314 meV down to 101 meV with an increase of B/C ratio from 600 to 18000 ppm in the gas reactants. For the heavily doped samples, a transition from thermally activated valence band conduction to hopping within the impurity band (with apparent activation energy 20 meV) was detected at temperatures 120–150 K. Numerical simulation was used to estimate the impurity DOS broadening. Accurate determination of continuously altering activation energy, which takes place during the transformation of conduction mechanisms, was proposed by numerical differentiation of the Arrhenius plot. With increase of boron doping level the gradual decreasing of capture cross section from 3 × 10{sup −13} down to 2 × 10{sup −17} cm{sup 2} was noticed. Moreover, for the hopping conduction the capture cross section becomes 4 orders of magnitude less (∼2 × 10{sup −20} cm{sup 2}). At T > T{sub room} in doped samples the birth of the second conductance peak was observed. We attribute it to a defect, related to the boron doping of the material.

  2. Increasing Immunization Compliance by Reducing Provisional Admittance.

    PubMed

    Davis, Wendy S; Varni, Susan E; Barry, Sara E; Frankowski, Barbara L; Harder, Valerie S

    2016-08-01

    Students in Vermont with incomplete or undocumented immunization status are provisionally admitted to schools and historically had a calendar year to resolve their immunization status. The process of resolving these students' immunization status was challenging for school nurses. We conducted a school-based quality improvement effort to increase student compliance with Vermont immunization regulations using a collaborative learning approach with public health school liaisons and school nurses from public schools to reduce provisional admittance in 2011-2012. Strategies included using a tracking system, accessing the immunization registry, promoting immunization importance, tracking immunization plans, and working with medical homes to update records. Participating school nurses observed decreases in the number of provisionally admitted students, although this reduction was not significantly different than matched comparison schools. We also found the number of provisionally admitted students fluctuated throughout the year and resolving the immunization status of New Americans and exchange students required special attention. Our approach supports the coordinated school health model and demonstrates the critical role school nurses play in improving population health outcomes. PMID:26699951

  3. Anomaly depth detection in trans-admittance mammography: a formula independent of anomaly size or admittivity contrast

    NASA Astrophysics Data System (ADS)

    Zhang, Tingting; Lee, Eunjung; Seo, Jin Keun

    2014-04-01

    Trans-admittance mammography (TAM) is a bioimpedance technique for breast cancer detection. It is based on the comparison of tissue conductivity: cancerous tissue is identified by its higher conductivity in comparison with the surrounding normal tissue. In TAM, the breast is compressed between two electrical plates (in a similar architecture to x-ray mammography). The bottom plate has many sensing point electrodes that provide two-dimensional images (trans-admittance maps) that are induced by voltage differences between the two plates. Multi-frequency admittance data (Neumann data) are measured over the range 50 Hz-500 kHz. TAM aims to determine the location and size of any anomaly from the multi-frequency admittance data. Various anomaly detection algorithms can be used to process TAM data to determine the transverse positions of anomalies. However, existing methods cannot reliably determine the depth or size of an anomaly. Breast cancer detection using TAM would be improved if the depth or size of an anomaly could also be estimated, properties that are independent of the admittivity contrast. A formula is proposed here that can estimate the depth of an anomaly independent of its size and the admittivity contrast. This depth estimation can also be used to derive an estimation of the size of the anomaly. The proposed estimations are verified rigorously under a simplified model. Numerical simulation shows that the proposed method also works well in general settings.

  4. Online Stability in Human-Robot Cooperation with Admittance Control.

    PubMed

    Dimeas, Fotios; Aspragathos, Nikos

    2016-01-01

    In the design of a compliant admittance controller for physical human-robot interaction, it is necessary to ensure stable and effective cooperation. The stability of the admittance controller is mainly threatened by a stiff environment. Many methods that guarantee stability in arbitrary environments, impose conservative control gains that limit the effectiveness of the cooperation. Inspired by previous work in frequency domain stability observers, a method is proposed in this paper to detect unstable behavior and stabilize the robot with online adaptation of the admittance control gains. The introduced instability index is based on frequency domain analysis, which very quickly detects unstable behavior by monitoring high frequency oscillation in the force signal. To treat the instability, an adaptation scheme of the admittance parameters is proposed, that relaxes conservative gains and improves the cooperation by considering the effect of variable admittance on the operators' effort. We investigate two human-robot co-manipulation tasks; cooperation within a zero stiffness environment and cooperation in contact with a stiff double-wall virtual environment. The proposed methods are validated experimentally with a number of subjects in cooperation with an LWR manipulator. PMID:26780819

  5. Improved multimodal admittance method in varying cross section waveguides.

    PubMed

    Maurel, Agnès; Mercier, Jean-François; Pagneux, Vincent

    2014-04-01

    An improved version of the multimodal admittance method in acoustic waveguides with varying cross sections is presented. This method aims at a better convergence with respect to the number of transverse modes that are taken into account. It is based on an enriched modal expansion of the pressure: the N first modes are the local transverse modes and a supplementary (N+1)th mode, called boundary mode, is a well-chosen transverse function orthogonal to the N first modes. This expansion leads to the classical form of the coupled mode equations where the component of the boundary mode is of evanescent character. Under this form, the multimodal admittance method based on the Riccati equation on the admittance matrix (the Dirichlet-to-Neumann operator) is straightforwardly implemented. With this supplementary mode, in addition to the improvement of the convergence of the pressure field, results show a superconvergence of the scattered field outside of the varying cross sections region. PMID:24711716

  6. Admittance of multiterminal quantum Hall conductors at kilohertz frequencies

    SciTech Connect

    Hernández, C.; Consejo, C.; Chaubet, C.; Degiovanni, P.

    2014-03-28

    We present an experimental study of the low frequency admittance of quantum Hall conductors in the [100 Hz, 1 MHz] frequency range. We show that the frequency dependence of the admittance of the sample strongly depends on the topology of the contacts connections. Our experimental results are well explained within the Christen and Büttiker approach for finite frequency transport in quantum Hall edge channels taking into account the influence of the coaxial cables capacitance. In the Hall bar geometry, we demonstrate that there exists a configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the sample and observe its dependence on the filling factor.

  7. CHARACTERIZATION OF A SPONTANEOUSLY TRANSFORMED CHICKEN MONONUCLEAR CELL LINE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe the characterization of a spontaneously transformed chicken monocytic cell line that developed as a single colony of cells in a heterophil culture that was inadvertently left in the incubator over a period of 25 days. These cells, hitherto named HTC, grow efficiently at both 37 C or 41 C...

  8. 9 CFR 117.3 - Admittance of animals.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Admittance of animals. 117.3 Section 117.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  9. 9 CFR 117.3 - Admittance of animals.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Admittance of animals. 117.3 Section 117.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  10. 9 CFR 117.3 - Admittance of animals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Admittance of animals. 117.3 Section 117.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  11. 9 CFR 117.3 - Admittance of animals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Admittance of animals. 117.3 Section 117.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  12. 9 CFR 117.3 - Admittance of animals.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Admittance of animals. 117.3 Section 117.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  13. TRANSFORMER

    DOEpatents

    Baker, W.R.

    1959-08-25

    Transformers of a type adapted for use with extreme high power vacuum tubes where current requirements may be of the order of 2,000 to 200,000 amperes are described. The transformer casing has the form of a re-entrant section being extended through an opening in one end of the cylinder to form a coaxial terminal arrangement. A toroidal multi-turn primary winding is disposed within the casing in coaxial relationship therein. In a second embodiment, means are provided for forming the casing as a multi-turn secondary. The transformer is characterized by minimized resistance heating, minimized external magnetic flux, and an economical construction.

  14. The long-wavelength admittance and effective elastic thickness of the Canadian Shield

    NASA Astrophysics Data System (ADS)

    Kirby, J. F.; Swain, C. J.

    2014-06-01

    The strength of the cratonic lithosphere has been controversial. On the one hand, many estimates of effective elastic thickness (Te) greatly exceed the crustal thickness, but on the other the great majority of cratonic earthquakes occur in the upper crust. This implies that the seismogenic thickness of cratons is much smaller than Te, whereas in the ocean basins they are approximately the same, leading to suspicions about the large Te estimates. One region where such estimates have been questioned is the Canadian Shield, where glacial isostatic adjustment (GIA) and mantle convection are thought to contribute to the long-wavelength undulations of the topography and gravity. To date these have not been included in models used to estimate Te from topography and gravity which conventionally are based only on loading and flexure. Here we devise a theoretical expression for the free-air (gravity/topography) admittance that includes the effects of GIA and convection as well as flexure and use it to estimate Te over the Canadian Shield. We use wavelet transforms for estimating the observed admittances, after showing that multitaper estimates, which have hitherto been popular for Te studies, have poor resolution at the long wavelengths where GIA and convection predominate, compared to wavelets. Our results suggest that Te over most of the shield exceeds 80 km, with a higher-Te core near the southwest shore of Hudson Bay. This means that the lack of mantle earthquakes in this craton is simply due to its high strength compared to the applied stresses.

  15. Impact and admittance modeling of the Isidis Planitia, Mars

    NASA Astrophysics Data System (ADS)

    Mancinelli, Paolo; Mondini, Alessandro C.; Pauselli, Cristina; Federico, Costanzo

    2015-11-01

    In this study, the impact event that produced the Martian Isidis basin (0-20°N and 70-100°E) was modeled using the iSALE hydrocode, and the current lithospheric structure was obtained comparing the calculated admittance from topography and gravity data, with the admittance from top-load and bottom-load flexure models. The best-fit admittance model was obtained using a bottom-load flexure with a thinned crust of 10 km, likely formed by cooling of the surficial melt pool after the impact, and an elastic thickness of 36 km. We found that the impact produced crustal excavation and thickening, surficial melt pool and temperatures >1500 K beneath the area where the free-air maxima is observed. The geometry resulting from the impact modeling is compatible with the radius of the Isidis basin. Derived thermal gradient and heat flux are in agreement with an early-Noachian epoch for the Isidis impact event and with the intense volcanic activity that followed the impact.

  16. Characterization of Roseomonas and Nocardioides spp. for arsenic transformation.

    PubMed

    Bagade, Aditi V; Bachate, Sachin P; Dholakia, Bhushan B; Giri, Ashok P; Kodam, Kisan M

    2016-11-15

    The metalloid arsenic predominantly exists in the arsenite [As(III)] and arsenate [As(V)]. These two forms are respectively oxidized and reduced by microbial redox processes. This study was designed to bioprospect arsenic tolerating bacteria from Lonar lake and to characterize their arsenic redoxing ability. Screening of sixty-nine bacterial species isolated from Lonar lake led to identification of three arsenic-oxidizing and seven arsenic-reducing species. Arsenite oxidizing isolate Roseomonas sp. L-159a being closely related to Roseomonas cervicalis ATCC 49957 oxidized 2mM As(III) in 60h. Gene expression of large and small subunits of arsenite oxidase respectively showed 15- and 17-fold higher expression. Another isolate Nocardioides sp. L-37a formed a clade with Nocardioides ghangwensis JC2055, exhibited normal growth with different carbon sources and pH ranges. It reduced 2mM As(V) in 36h and showed constitutive expression of arsenate reductase which increased over 4-fold upon As(V) exposure. Genetic markers related to arsenic transformation were identified and characterized from the two isolates. Moderate resistance against the arsenicals was exhibited by the two isolates in the range of 1-5mM for As(III) and 1-200mM for As(V). Altogether we provide multiple evidences to indicate that Roseomonas sp. and Nocardioides sp. exhibited arsenic transformation ability. PMID:27498193

  17. Cross-spectral recognition method of bridge deck aerodynamic admittance function

    NASA Astrophysics Data System (ADS)

    Zhao, Lin; Ge, Yaojun

    2015-12-01

    This study proposes a new identification algorithm about the admittance function, which can estimate the full set of six aerodynamic admittance functions considering cross power spectral density functions about the forces and the turbulence components. The method was first numerically validated through Monte Carlo simulations, and then adopted to estimate the aerodynamic admittance of a streamlined bridge deck. The identification method was further validated through a comparison between the numerical calculation and wind tunnel tests on a moving bridge section.

  18. High Power Piezoelectric Characterization for Piezoelectric Transformer Development

    NASA Astrophysics Data System (ADS)

    Ural, Seyit O.

    The major goal was to develop characterization techniques to identify and define guidelines to manufacture high power density actuators. We particularly aim at improving the strengths of piezoelectric transformers, namely the high efficiency, ease of manufacturing, low electromagnetic noise, and high power to weight ratio resulting in an adaptor application by identifying material limitations, geometrical limitations and offer guidelines to counter drawbacks limiting the power density. There are 3 losses present in piezoelectrics. Namely dielectric, elastic and piezoelectric losses. These losses can be calculated using mechanical quality factors of the resonating piezoelectric actuator. But in order to calculate all three losses, the mechanical quality factor for resonance and anti resonance need to be measured. Although the mechanical quality factor for resonance is conventionally measured, measurements in antiresonance have been ignored. Since there was no unique measurement technique to address antiresonance and resonance Q in one single sweep, in this study constant vibration velocity method was developed. During the constant vibration velocity measurement, the input electrical energy is monitored and significant differences between resonance and antiresonance drives are observed. For the same output work (identical vibration velocity) significant differences in the losses were observed. Thermographic images have shown increasing temperature differences for resonance and antiresonance nodal point temperatures, with higher vibration velocities. The theoretical evaluation identified the difference observed in the mechanical quality factors at resonance and antiresonance to stem from the piezoelectric loss. In order to investigate losses in the absence of thermal effects a transient characterization technique was adopted. The burst technique, originally developed for characterization of the mechanical quality factor at resonance, has been modified with a switch

  19. Quality control of dairy products using single frequency admittance measurements

    NASA Astrophysics Data System (ADS)

    Mabrook, M. F.; Darbyshire, A. M.; Petty, M. C.

    2006-02-01

    A reusable device for the detection of adulteration in dairy products such as milk and cream has been developed. The ac electrical admittance spectra of different samples have been studied using both uncoated and alkyl mercaptan-coated gold electrodes. Uncoated gold electrodes exhibited a polarization at around 250 Hz for full fat milk, while mercaptan-coated gold electrodes showed a similar effect at around 2 kHz. The characteristics at 100 kHz and 8 °C for all skimmed milk samples revealed a linear decrease in conductance with increasing water content over the entire range of water concentration. In contrast, the conductance of full fat milk, single and double cream, showed a linear decrease only at added water concentration higher than 6%. At lower concentrations, these dairy products exhibited anomalous conductivity maxima.

  20. Automatically calibrating admittances in KATE's autonomous launch operations model

    NASA Astrophysics Data System (ADS)

    Morgan, Steve

    1992-09-01

    This report documents a 1000-line Symbolics LISP program that automatically calibrates all 15 fluid admittances in KATE's Autonomous Launch Operations (ALO) model. (KATE is Kennedy Space Center's Knowledge-based Autonomous Test Engineer, a diagnosis and repair expert system created for use on the Space Shuttle's various fluid flow systems.) As a new KATE application, the calibrator described here breaks new ground for KSC's Artificial Intelligence Lab by allowing KATE to both control and measure the hardware she supervises. By automating a formerly manual process, the calibrator: (1) saves the ALO model builder untold amounts of labor; (2) enables quick repairs after workmen accidently adjust ALO's hand valves; and (3) frees the modeler to pursue new KATE applications that previously were too complicated. Also reported are suggestions for enhancing the program: (1) to calibrate ALO's TV cameras, pumps, and sensor tolerances; and (2) to calibrate devices in other KATE models, such as the shuttle's LOX and Environment Control System (ECS).

  1. Automatically calibrating admittances in KATE's autonomous launch operations model

    NASA Technical Reports Server (NTRS)

    Morgan, Steve

    1992-01-01

    This report documents a 1000-line Symbolics LISP program that automatically calibrates all 15 fluid admittances in KATE's Autonomous Launch Operations (ALO) model. (KATE is Kennedy Space Center's Knowledge-based Autonomous Test Engineer, a diagnosis and repair expert system created for use on the Space Shuttle's various fluid flow systems.) As a new KATE application, the calibrator described here breaks new ground for KSC's Artificial Intelligence Lab by allowing KATE to both control and measure the hardware she supervises. By automating a formerly manual process, the calibrator: (1) saves the ALO model builder untold amounts of labor; (2) enables quick repairs after workmen accidently adjust ALO's hand valves; and (3) frees the modeler to pursue new KATE applications that previously were too complicated. Also reported are suggestions for enhancing the program: (1) to calibrate ALO's TV cameras, pumps, and sensor tolerances; and (2) to calibrate devices in other KATE models, such as the shuttle's LOX and Environment Control System (ECS).

  2. Use of paravascular admittance waveforms to monitor relative change in arterial blood pressure

    NASA Astrophysics Data System (ADS)

    Zielinski, Todd M.; Hettrick, Doug; Cho, Yong

    2010-04-01

    Non-invasive methods to monitor ambulatory blood pressure often have limitations that can affect measurement accuracy and patient adherence [1]. Minimally invasive measurement of a relative blood pressure surrogate with an implantable device may provide a useful chronic diagnostic and monitoring tool. We assessed a technique that uses electrocardiogram and paravascular admittance waveform morphology analysis to one, measure a time duration (vascular tone index, VTI in milliseconds) change from the electrocardiogram R-wave to admittance waveform peak and two, measure the admittance waveform minimum, maximum and magnitude as indicators of change in arterial compliance/distensibility or pulse pressure secondary to change in afterload. Methods: Five anesthetized domestic pigs (32 ± 4.2 kg) were used to study the effects of phenylephrine (1-5 ug/kg/min) on femoral artery pressure and admittance waveform morphology measured with a quadrapolar electrode array catheter placed next to the femoral artery to assess the relative change in arterial compliance due to change in peripheral vascular tone. Results: Statistical difference was observed (p < 0.05) comparing baseline VTI to phenylephrine VTI (246 ± .05 ms to 320 ± .07 ms) and baseline admittance waveform maximum to phenylephrine admittance waveform maximum (0.0148 ± .002 siemens to 0.0151 ± .002 siemens). Conclusion: Chronic minimally invasive admittance measurement techniques that monitor relative change in blood pressure may be suitable for implantable devices to detect progression of cardiovascular disease such as hypertension.

  3. Surface acoustic admittance of highly porous open-cell, elastic foams

    NASA Technical Reports Server (NTRS)

    Lambert, R. F.

    1983-01-01

    This work presents a comprehensive study of the surface acoustic admittance properties of graded sizes of open-cell foams that are highly porous and elastic. The intrinsic admittance as well as properties of samples of finite depth were predicted and then measured for sound at normal incidence over a frequency range extending from about 35-3500 Hz. The agreement between theory and experiment for a range of mean pore size and volume porosity is excellent. The implications of fibrous structure on the admittance of open-cell foams is quite evident from the results.

  4. Simultaneous reconstruction of permittivity and conductivity using multi-frequency admittance measurement in electrical capacitance tomography

    NASA Astrophysics Data System (ADS)

    Zhang, Maomao; Soleimani, Manuchehr

    2016-02-01

    Electrical capacitance tomography (ECT) is an imaging method mainly capable of reconstructing dielectric permittivity. Generally, the reactance part of complex admittance is measured in a selected frequency. This paper presents for the first time an in depth and systematic analysis of complex admittance data for simultaneous reconstruction of both electrical conductivity and dielectric permittivity. A complex-valued forward model, Jacobian matrix and inverse solution are developed in the time harmonic excitation mode to allow for multi-frequency measurements. Realistic noise models are used to evaluate the performance of complex admittance ECT in a range of excitation frequencies. This paper demonstrates far greater potential for ECT as a versatile imaging tool through novel analysis of complex admittance imaging using a dual conductivity permittivity inversion method. The paper demonstrates that various classes of contactless capacitance based measurement devices can be analysed through complex multi-frequency ECT.

  5. 48 CFR 3022.101-70 - Admittance of union representatives to DHS installations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... APPLICATION OF LABOR LAWS TO GOVERNMENT ACQUISITIONS Basic Labor Policies 3022.101-70 Admittance of union... Administration or United States Secret Service installations and work sites is not governed by this rule, but...

  6. 48 CFR 3022.101-70 - Admittance of union representatives to DHS installations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... APPLICATION OF LABOR LAWS TO GOVERNMENT ACQUISITIONS Basic Labor Policies 3022.101-70 Admittance of union... Administration or United States Secret Service installations and work sites is not governed by this rule, but...

  7. 48 CFR 3022.101-70 - Admittance of union representatives to DHS installations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... APPLICATION OF LABOR LAWS TO GOVERNMENT ACQUISITIONS Basic Labor Policies 3022.101-70 Admittance of union... Administration or United States Secret Service installations and work sites is not governed by this rule, but...

  8. 48 CFR 3022.101-70 - Admittance of union representatives to DHS installations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... APPLICATION OF LABOR LAWS TO GOVERNMENT ACQUISITIONS Basic Labor Policies 3022.101-70 Admittance of union... Administration or United States Secret Service installations and work sites is not governed by this rule, but...

  9. In-situ characterization of transformation plasticity during an isothermal austenite-to-bainite phase transformation

    SciTech Connect

    Holzweissig, M.J.; Canadinc, D.; Maier, H.J.

    2012-03-15

    This paper elucidates the stress-induced variant selection process during the isothermal austenite-to-bainite phase transformation in a tool steel. Specifically, a thorough set of experiments combining electron backscatter diffraction and in-situ digital image correlation (DIC) was carried out to establish the role of superimposed stress level on the evolution of transformation plasticity (TP) strains. The important finding is that TP increases concomitant with the superimposed stress level, and strain localization accompanies phase transformation at all stress levels considered. Furthermore, TP strain distribution within the whole material becomes more homogeneous with increasing stress, such that fewer bainitic variants are selected to grow under higher stresses, yielding a more homogeneous strain distribution. In particular, the bainitic variants oriented along [101] and [201] directions are favored to grow parallel to the loading axis and are associated with large TP strains. Overall, this very first in-situ DIC investigation of the austenite-to-bainite phase transformation in steels evidences the clear relationship between the superimposed stress level, variant selection, and evolution of TP strains. - Highlights: Black-Right-Pointing-Pointer Local variations of strain were observed by DIC throughout the phase transformation. Black-Right-Pointing-Pointer The study clearly established the role of the stress-induced variant selection. Black-Right-Pointing-Pointer Variant selection is a key parameter that governs distortion.

  10. Preparation, characterization, and sequential transformation of dicarbide cluster compounds with permetalated ethyne, ethene, and ethane structures

    SciTech Connect

    Akita, Munetaka; Sugimoto, Shuichiro; Tanaka, Masako; Moro-oka, Yoshihiko

    1992-09-09

    The preparation, characterization and sequential transformation of dicarbide cluster compounds with permetalated ethyne, ethene and ethane structures is discussed. The group reporting has developed a preparative method for ethynediyldimetal complexes via deprotonation. 10 refs., 3 figs.

  11. TRANSFORMATION

    SciTech Connect

    LACKS,S.A.

    2003-10-09

    Transformation, which alters the genetic makeup of an individual, is a concept that intrigues the human imagination. In Streptococcus pneumoniae such transformation was first demonstrated. Perhaps our fascination with genetics derived from our ancestors observing their own progeny, with its retention and assortment of parental traits, but such interest must have been accelerated after the dawn of agriculture. It was in pea plants that Gregor Mendel in the late 1800s examined inherited traits and found them to be determined by physical elements, or genes, passed from parents to progeny. In our day, the material basis of these genetic determinants was revealed to be DNA by the lowly bacteria, in particular, the pneumococcus. For this species, transformation by free DNA is a sexual process that enables cells to sport new combinations of genes and traits. Genetic transformation of the type found in S. pneumoniae occurs naturally in many species of bacteria (70), but, initially only a few other transformable species were found, namely, Haemophilus influenzae, Neisseria meningitides, Neisseria gonorrheae, and Bacillus subtilis (96). Natural transformation, which requires a set of genes evolved for the purpose, contrasts with artificial transformation, which is accomplished by shocking cells either electrically, as in electroporation, or by ionic and temperature shifts. Although such artificial treatments can introduce very small amounts of DNA into virtually any type of cell, the amounts introduced by natural transformation are a million-fold greater, and S. pneumoniae can take up as much as 10% of its cellular DNA content (40).

  12. Global Admittance Estimates of Elastic and Crustal Thickness of Venus: Results from Top, Hot Spot, and Bottom Loading Models

    NASA Technical Reports Server (NTRS)

    Smrekar, S. E.; Anderson, F. S.

    2005-01-01

    We have calculated admittance spectra using the spatio-spectral method [14] for Venus by moving the central location of the spectrum over a 1 grid, create 360x180 admittance spectra. We invert the observed admittance using top-loading (TL), hot spot (HS), and bottom loading (BL) models, resulting in elastic, crustal, and lithospheric thickness estimates (Te, Zc, and Zl) [0]. The result is a global map for interpreting subsurface structure. Estimated values of Te and Zc concur with previous TL local admittance results, but BL estimates indicate larger values than previously suspected.

  13. Characterization of insoluble fractions of TNT transformed by composting

    SciTech Connect

    Caton, J.E.; Ho, C.H.; Williams, R.T.; Griest, W.H. )

    1994-05-01

    Soil contaminated with explosives was supplemented with carbon-14 labelled 2,4,6-trinitrotoluene ([sup 14]C-TNT) and was composted in a field static pile composting experiment. After 90 d of composting, the distribution of carbon-14 ([sup 14]C) activity in fractions from acetonitrile extraction ([open quotes]free[close quotes] fraction, 1.2% of the initial [sup 14]C-activity) and filtration ([open quotes]insoluble-particle[close quotes] fraction, 17.9%), alkaline hydrolysis ([open quotes]insoluble-hydrolyzable[close quotes] fraction, 56.8%), and combustion of the residue ([open quotes]insoluble-nonhydrolyzable[close quotes] fraction, 4.7%) showed that the bulk of the [sup 14]C-activity, and presumably transformed product(s) of the [sup 14]C-TNT, accumulated in a nonextractable, but hydrolyzable fraction. Repetitive aqueous leaching of the compost and also ultraviolet light irradiation followed by leaching suggest that the insoluble fraction of transformed TNT should not be released appreciably by the action of acid rain or sunlight. 16 refs., 11 figs., 2 tabs.

  14. A high frequency transformer model for the EMTP

    SciTech Connect

    Morched, A.; Marti, L.; Ottevangers, J. )

    1993-07-01

    A model to simulate the high frequency behavior of a power transformer is presented. This model is based on the frequency characteristics of the transformer admittance matrix between its terminals over a given range of frequencies. The transformer admittance characteristics can be obtained from measurements or from detailed internal models based on the physical layout of the transformer. The elements of the nodal admittance matrix are approximated with rational functions consisting of real as well as complex conjugate poles and zeros. These approximations are realized in the form of an RLC network in a format suitable for direct use with EMTP. The high frequency transformer model can be used as a stand-alone linear model or as an add-on module of a more comprehensive model where iron core nonlinearities are represented in detail.

  15. Synthesis and characterization of JBW structure and its thermal transformation

    SciTech Connect

    Hegazy, Eman Z.; Kosa, Samia A.; Abd El Maksod, Islam Hamdy

    2012-12-15

    In this paper, JBW zeolite prepared from Egyptian kaolin was investigated by means of XRD, IR, SEM, EDX and ion exchange of some heavy metals. Adsorption isotherms were used to investigate the structure and properties of the prepared zeolite. XRD analysis showed that the JBW was a pure crystalline phase with orthorhombic crystal symmetry. Thermal treatment showed that the JBW transformed into the It-Carn phase at 1000 Degree-Sign C through an intermediate crystalline alumino silicate phase. SEM images showed that the JBW crystallised in a cylindrical shape. However, spherical agglomerates were observed at lower magnifications. The ion exchange isotherms with Cu{sup 2+}, Ni{sup 2+} and Co{sup 2+} were found to follow a Freundlich isotherm. In addition, it shows higher affinity towards Cu{sup 2+} than other ions. - Graphical abstract: JBW zeolite structure was prepared from Egyptian kaolin and characterised. XRD analysis showed that the JBW was a pure crystalline phase with orthorhombic crystal symmetry. Thermal treatment showed that the JBW transformed into the It-Carn phase at 1000 Degree-Sign C through an intermediate crystalline alumino silicate phase. Highlights: Black-Right-Pointing-Pointer Egyptian kaolin was successfully used to prepare pure phase of JBW Structure. Black-Right-Pointing-Pointer JBW is stable till <300 Degree-Sign C. Black-Right-Pointing-Pointer JBW phase crystallizes as cylindrical shape but agglomerates in a Nano spherical shape. Black-Right-Pointing-Pointer The ion exchange isotherms of Cu{sup 2+}, Ni{sup 2+}, and Co{sup 2+} followed up Freundlich isotherm. Black-Right-Pointing-Pointer Selectivity towards Cu{sup 2+} is much higher than Co{sup 2+} or Ni{sup 2+}.

  16. Evolute-based Hough transform method for characterization of ellipsoids.

    PubMed

    Kaytanli, B; Valentine, M T

    2013-03-01

    We propose a novel and algorithmically simple Hough transform method that exploits the geometric properties of ellipses to enable the robust determination of the ellipse position and properties. We make use of the unique features of the evolute created by Hough voting along the gradient vectors of a two-dimensional image to determine the ellipse centre, orientation and aspect ratio. A second one-dimensional voting is performed on the minor axis to uniquely determine the ellipse size. This reduction of search space substantially simplifies the algorithmic complexity. To demonstrate the accuracy of our method, we present analysis of single and multiple ellipsoidal particles, including polydisperse and imperfect ellipsoids, in both simulated images and electron micrographs. Given its mathematical simplicity, ease of implementation and reasonable algorithmic completion time, we anticipate that the proposed method will be broadly useful for image processing of ellipsoidal particles, including their detection and tracking for studies of colloidal suspensions, and for applications to drug delivery and microrheology. PMID:23301634

  17. Analytical ultrasonics for characterization of metallurgical microstructures and transformations

    NASA Technical Reports Server (NTRS)

    Rosen, M.

    1986-01-01

    The application of contact (piezoelectric) and noncontact (laser generation and detection) ultrasonic techniques for dynamic investigation of precipitation hardening processes in aluminum alloys, as well as crystallization and phase transformation in rapidly solidified amorphous and microcrystalline alloys is discussed. From the variations of the sound velocity and attenuation the precipitation mechanism and kinetics were determined. In addition, a correlation was established between the observed changes in the velocity and attenuation and the mechanical properties of age-hardenable aluminum alloys. The behavior of the elastic moduli, determined ultrasonically, were found to be sensitive to relaxation, crystallization and phase decomposition phenomena in rapidly solidified metallic glasses. Analytical ultrasonics enables determination of the activation energies and growth parameters of the reactions. Therefrom theoretical models can be constructed to explain the changes in mechanical and physical properties upon heat treatment of glassy alloys. The composition dependence of the elastic moduli in amorphous Cu-Zr alloys was found to be related to the glass transition temperature, and consequently to the glass forming ability of these alloys. Dynamic ultrasonic analysis was found to be feasible for on-line, real-time, monitoring of metallurgical processes.

  18. Solid state of a new PDE-5 inhibitor DA-8159: characterization, dissolution, transformation.

    PubMed

    Ryu, Ji Yoon; Sohn, Young-Taek

    2012-05-01

    The polymorphic forms of a new PDE-5 inhibitor DA-8159 were prepared and characterized by differential scanning calorimetry (DSC), powder X-ray diffractometry (PXRD) and thermogravimetric analysis (TG). Two crystal forms and one amorphous form of DA-8159 have been isolated by recrystallization and characterized by DSC, TG and PXRD. From the TG data it was confirmed that two crystal forms are neither solvates nor hydrates. The PXRD patterns of the two crystal forms were different. In the dissolution studies in simulated intestinal fluid at 37 ± 0.5°C, the solubility decreased in the order of amorphous form > Form 1 > Form 2. After storage of 60 days, Form 1 was transformed to Form 2. Form 2 was not transformed. The amorphous form was transformed to Form 2 at 52% R.H. and 95% R.H., but it did not transform at 0% R.H. PMID:22644853

  19. Systematic characterization of the Herschel SPIRE Fourier Transform Spectrometer

    NASA Astrophysics Data System (ADS)

    Hopwood, R.; Polehampton, E. T.; Valtchanov, I.; Swinyard, B. M.; Fulton, T.; Lu, N.; Marchili, N.; van der Wiel, M. H. D.; Benielli, D.; Imhof, P.; Baluteau, J.-P.; Pearson, C.; Clements, D. L.; Griffin, M. J.; Lim, T. L.; Makiwa, G.; Naylor, D. A.; Noble, G.; Puga, E.; Spencer, L. D.

    2015-05-01

    A systematic programme of calibration observations was carried out to monitor the performance of the Spectral and Photometric Imaging REceiver (SPIRE) Fourier Transform Spectrometer (FTS) instrument on board the Herschel Space Observatory. Observations of planets (including the prime point-source calibrator, Uranus), asteroids, line sources, dark sky and cross-calibration sources were made in order to monitor repeatability and sensitivity, and to improve FTS calibration. We present a complete analysis of the full set of calibration observations and use them to assess the performance of the FTS. Particular care is taken to understand and separate out the effect of pointing uncertainties, including the position of the internal beam steering mirror for sparse observations in the early part of the mission. The repeatability of spectral-line centre positions is <5 km s-1, for lines with signal-to-noise ratios >40, corresponding to <0.5-2.0 per cent of a resolution element. For spectral-line flux, the repeatability is better than 6 per cent, which improves to 1-2 per cent for spectra corrected for pointing offsets. The continuum repeatability is 4.4 per cent for the SPIRE Long Wavelength spectrometer (SLW) band and 13.6 per cent for the SPIRE Short Wavelength spectrometer (SSW) band, which reduces to ˜1 per cent once the data have been corrected for pointing offsets. Observations of dark sky were used to assess the sensitivity and the systematic offset in the continuum, both of which were found to be consistent across the FTS-detector arrays. The average point-source calibrated sensitivity for the centre detectors is 0.20 and 0.21 Jy [1σ; 1 h], for SLW and SSW. The average continuum offset is 0.40 Jy for the SLW band and 0.28 Jy for the SSW band.

  20. Volkov transform generalized projection algorithm for attosecond pulse characterization

    NASA Astrophysics Data System (ADS)

    Keathley, P. D.; Bhardwaj, S.; Moses, J.; Laurent, G.; Kärtner, F. X.

    2016-07-01

    An algorithm for characterizing attosecond extreme ultraviolet pulses that is not bandwidth-limited, requires no interpolation of the experimental data, and makes no approximations beyond the strong-field approximation is introduced. This approach fully incorporates the dipole transition matrix element into the retrieval process. Unlike attosecond retrieval methods such as phase retrieval by omega oscillation filtering (PROOF), or improved PROOF, it simultaneously retrieves both the attosecond and infrared (IR) pulses, without placing fundamental restrictions on the IR pulse duration, intensity or bandwidth. The new algorithm is validated both numerically and experimentally, and is also found to have practical advantages. These include an increased robustness to noise, and relaxed requirements for the size of the experimental dataset and the intensity of the streaking pulse.

  1. Effect of nonzero surface admittance on receptivity and stability of compressible boundary layer

    NASA Technical Reports Server (NTRS)

    Choudhari, Meelan

    1994-01-01

    The effect of small-amplitude short-scale variations in surface admittance on the acoustic receptivity and stability of two-dimensional compressible boundary layers is examined. In the linearized limit, the two problems are shown to be related both physically and mathematically. This connection between the two problems is used, in conjunction with some previously reported receptivity results, to infer the modification of stability properties due to surface permeability. Numerical calculations are carried out for a self-similar flat-plate boundary layer at subsonic and low supersonic speeds. Variations in mean suction velocity at the perforated admittance surface can also induce receptivity to an acoustic wave. For a subsonic boundary layer, the dependence of admittance-induced receptivity on the acoustic-wave orientation is significantly different from that of the receptivity produced via mean suction variation. The admittance-induced receptivity is generally independent of the angle of acoustic incidence, except in a relatively narrow range of upstream-traveling waves for which the receptivity becomes weaker. However, this range of angles is precisely that for which the suction-induced receptivity tends to be large. At supersonic Mach numbers, the admittance-induced receptivity to slow acoustic models is relatively weaker than that in the case of the fast acoustic modes. We also find that purely real values for the surface admittance tend to have a destabilizing effect on the evolution of an instability wave over a slightly permeable surface. The limits on the validity of the linearized approximation are also assessed in one specific case.

  2. Characterization, Modeling, and Energy Harvesting of Phase Transformations in Ferroelectric Materials

    NASA Astrophysics Data System (ADS)

    Dong, Wenda

    Solid state phase transformations can be induced through mechanical, electrical, and thermal loading in ferroelectric materials that are compositionally close to morphotropic phase boundaries. Large changes in strain, polarization, compliance, permittivity, and coupling properties are typically observed across the phase transformation regions and are phenomena of interest for energy harvesting and transduction applications where increased coupling behavior is desired. This work characterized and modeled solid state phase transformations in ferroelectric materials and assessed the potential of phase transforming materials for energy harvesting applications. Two types of phase transformations were studied. The first type was ferroelectric rhombohedral to ferroelectric orthorhombic observed in lead indium niobate lead magnesium niobate lead titanate (PIN-PMN-PT) and driven by deviatoric stress, temperature, and electric field. The second type of phase transformation is ferroelectric to antiferroelectric observed in lead zirconate titanate (PZT) and driven by pressure, temperature, and electric field. Experimental characterizations of the phase transformations were conducted in both PIN-PMN-PT and PZT in order to understand the thermodynamic characteristics of the phase transformations and map out the phase stability of both materials. The ferroelectric materials were characterized under combinations of stress, electric field, and temperature. Material models of phase transforming materials were developed using a thermodynamic based variant switching technique and thermodynamic observations of the phase transformations. These models replicate the phase transformation behavior of PIN-PMN-PT and PZT under mechanical and electrical loading conditions. The switching model worked in conjunction with linear piezoelectric equations as ferroelectric/ferroelastic constitutive equations within a finite element framework that solved the mechanical and electrical field equations

  3. Admittance of Au/1,4-benzenedithiol/Au single-molecule junctions

    NASA Astrophysics Data System (ADS)

    Yamauchi, Kazumasa; Kurokawa, Shu; Sakai, Akira

    2012-12-01

    Employing the admittance formula for double-barrier junctions [Fu and Dudley, Phys. Rev. Lett. 70, 65 (1993)], we have estimated an ac susceptance (imaginary part of admittance) of Au/1,4-benzenedithiol/Au single-molecule junctions from their current-voltage characteristics. In the MHz regime, we find that the junction susceptance shows a very small (˜0.1 aF) capacitive component that can be entirely masked by a larger electrode capacitance. Direct ac signal transmission measurements up to 1 GHz reveal no molecular signals and confirm the smallness of the molecular capacitance in the MHz regime.

  4. Complete characterization of a spatiotemporal pulse shaper with two-dimensional Fourier transform spectral interferometry

    NASA Astrophysics Data System (ADS)

    Amir, W.; Planchon, T. A.; Durfee, C. G.; Squier, J. A.

    2007-04-01

    Spatiotemporal pulse shaping is characterized with two-dimensional Fourier transform spectral interferometry. A deformable-mirror-based bidimensional pulse shaper is used to create simple spatiotemporal structures on a femtosecond pulse, structures that are directly calculated from the measured spatiospectral phases and intensities.

  5. Characterization of fluids involved in the Gneiss-Charnockite transformation in Southern Kerala (India)

    NASA Technical Reports Server (NTRS)

    Klatt, E.; Hoernes, S.; Raith, M.

    1988-01-01

    The characterization of fluids involved in the gneiss-charnockite transformation in southern Kerala are discussed. Using a variety of techniques, including microthermometry, Raman laser probe analysis, and mass spectrometry, it was concluded that the CO2-rich, N2-bearing metamorphic fluids in these rocks were internally-derived rather than having been introduced by CO2-streaming.

  6. A study of the ionic conduction of mica surface by admittance spectroscopy

    NASA Astrophysics Data System (ADS)

    Dolci, D.; Aloisi, G.; Lanzi, L.; Carlà, M.

    2007-08-01

    The ionic conduction on the surface of humid mica has been analyzed by admittance spectroscopy as a function of relative humidity for different surface treatments. Measurements at low frequency indicate that water adsorption proceeds first in the form of a strongly adsorbed uniform thin layer, then with the formation of highly inhomogeneous thick aggregates.

  7. Admittance model for the shuttle remote manipulator system in four configurations. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Papadopoulos, Loukas; Tolson, Robert H.

    1993-01-01

    A possible scenario for robot task performance in space is to mount two small, dexterous arms to the end of the Shuttle Remote Manipulator System (SRMS). As these small robots perform tasks, the flexibility of the SRMS may cause unsuccessful task executions. In order to simulate the dynamic coupling between the SRMS and the arms, admittance models of the SRMS in four brakes locked configurations were developed. The admittance model permits calculation of the SRMS end-effector response due to end-effector disturbing forces. The model will then be used in conjunction with a Stewart Platform, a vehicle emulation system. An application of the admittance model was shown by simulating the disturbing forces using two SRMS payloads, the Dextrous Orbital Servicing System (DOSS) manipulator and DOSS carrying a 1000 lb. cylinder. Mode by mode comparisons were conducted to determine the minimum number of modes required in the admittance model while retaining dynamic fidelity. It was determined that for all four SRMS configurations studied, between 4 and 6 modes of the SRMS structure (depending on the excitation loads) were sufficient to retain tolerance of 0.01 inches and 0.01 deg. These tolerances correspond to the DOSS manipulator carrying no object. When the DOSS carries the 1000 lb. cylinder, between 15 and 20 modes were sufficient, approximately three or four times as many modes as for the unloaded case.

  8. Damage detection on the joint of steel frame through high-frequency admittance signals

    NASA Astrophysics Data System (ADS)

    Wang, Dansheng; Zhu, Hongping; Zhou, Huaqiang; Yang, Haiping

    2008-11-01

    The basic idea of a piezoelectric admittance (reciprocal of impedance) technique for structural health monitoring is presented in this paper. An experimental study on damage detection of a steel frame structure is operated by the use of the high-frequency piezoelectric admittance signals. In this experiment, three PZT active sensors are bonded to three different components around a joint of the steel frame separately, and the looseness of bolts is identified by monitoring the variations of piezoelectric admittance measurements. From the experimental results it is found that the PZT active sensors hold the ability to detect structural local damage, i.e. they are insensitive to the damage in far fields. Subsequently, two damage indexes, the covariance and the cross correlation coefficient between two real admittance data sets are defined respectively, by which the extent of damage of the frame structure is evaluated. It is found that the cross correlation coefficient index can correctly reflect the damage extent of the frame structure qualitatively in different frequency ranges, but the covariance index can not.

  9. 48 CFR 1222.101-70 - Admittance of union representatives to DOT installations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Basic Labor Policies 1222.101-70 Admittance of union representatives to DOT installations. (a) It is DOT policy to admit labor union representatives of contractor employees to DOT installations to visit work sites and transact labor union business with contractors, their employees, or union stewards pursuant...

  10. 48 CFR 1222.101-70 - Admittance of union representatives to DOT installations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Basic Labor Policies 1222.101-70 Admittance of union representatives to DOT installations. (a) It is DOT policy to admit labor union representatives of contractor employees to DOT installations to visit work sites and transact labor union business with contractors, their employees, or union stewards pursuant...

  11. 48 CFR 1222.101-70 - Admittance of union representatives to DOT installations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Basic Labor Policies 1222.101-70 Admittance of union representatives to DOT installations. (a) It is DOT policy to admit labor union representatives of contractor employees to DOT installations to visit work sites and transact labor union business with contractors, their employees, or union stewards pursuant...

  12. 48 CFR 1222.101-70 - Admittance of union representatives to DOT installations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Admittance of union representatives to DOT installations. 1222.101-70 Section 1222.101-70 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION SOCIOECONOMIC PROGRAMS APPLICATION OF LABOR LAWS TO GOVERNMENT ACQUISITIONS Basic Labor Policies...

  13. Localization and Characterization of the Carbon Tetrachloride Transformation Activity of Pseudomonas sp. Strain KC

    PubMed Central

    Dybas, M. J.; Tatara, G. M.; Criddle, C. S.

    1995-01-01

    Previous research has established that Pseudomonas sp. strain KC rapidly transforms carbon tetrachloride (CT) to carbon dioxide (45 to 55%), a nonvolatile fraction (45 to 55%), and a cell-associated fraction ((equiv)5%) under denitrifying, iron-limited conditions. The present study provides additional characterization of the nonvolatile fraction, demonstrates that electron transfer plays a role in the transformation, and establishes the importance of both extracellular and intracellular factors. Experiments with (sup14)C-labeled CT indicate that more than one nonvolatile product is produced during CT transformation by strain KC. One of these products, accounting for about 20% of the [(sup14)C]CT transformed, was identified as formate on the basis of its elution time from an ion-exchange column, its boiling point, and its conversion to (sup14)CO(inf2) when incubated with formate dehydrogenase. Production of formate requires transfer of two electrons to the CT molecule. The role of electron transfer was also supported by experiments demonstrating that stationary-phase cells that do not transform CT can be stimulated to transform CT when supplemented with acetate (electron donor), nitrate (electron acceptor), or a protonophore (carbonyl cyanide m-chlorophenylhydrazone). The location of transformation activity was also evaluated. By themselves, washed cells did not transform CT to a significant degree. Occasionally, CT transformation was observed by cell-free culture supernatant, but this activity was not reliable. Rapid and reliable CT transformation was only obtained when washed whole cells were reconstituted with culture supernatant, indicating that both extracellular and intracellular factors are normally required for CT transformation. Fractionation of culture supernatant by ultrafiltration established that the extracellular factor or factors are small, with an apparent molecular mass of less than 500 Da. The extracellular factor or factors were stable after

  14. Voice source characterization using pitch synchronous discrete cosine transform for speaker identification.

    PubMed

    Ramakrishnan, A G; Abhiram, B; Prasanna, S R Mahadeva

    2015-06-01

    A characterization of the voice source (VS) signal by the pitch synchronous (PS) discrete cosine transform (DCT) is proposed. With the integrated linear prediction residual (ILPR) as the VS estimate, the PS DCT of the ILPR is evaluated as a feature vector for speaker identification (SID). On TIMIT and YOHO databases, using a Gaussian mixture model (GMM)-based classifier, it performs on par with existing VS-based features. On the NIST 2003 database, fusion with a GMM-based classifier using MFCC features improves the identification accuracy by 12% in absolute terms, proving that the proposed characterization has good promise as a feature for SID studies. PMID:26093457

  15. Simultaneous recovery of admittivity and body shape in electrical impedance tomography: an experimental evaluation

    NASA Astrophysics Data System (ADS)

    Dardé, Jérémi; Hyvönen, Nuutti; Seppänen, Aku; Staboulis, Stratos

    2013-08-01

    In this paper, the simultaneous retrieval of the exterior boundary shape and the interior admittivity distribution of an examined body in electrical impedance tomography is considered. The reconstruction method is built for the complete electrode model and it is based on the Fréchet derivative of the corresponding current-to-voltage map with respect to the body shape. The reconstruction problem is cast into the Bayesian framework, and maximum a posteriori estimates for the admittivity and the boundary geometry are computed. The feasibility of the approach is evaluated by experimental data from water tank measurements. The results demonstrate that the proposed method has potential for handling an unknown body shape in a practical setting.

  16. Dielectric studies of boron sub phthalocyanine chloride thin films by admittance spectroscopic techniques

    NASA Astrophysics Data System (ADS)

    Kalia, Sameer; Mahajan, Aman; Neerja, Sharma, Anshul Kumar; Kumar, Sanjeev; Bedi, R. K.

    2016-05-01

    The dielectric properties of Boron Sub Phthalocyanine Chloride (Cl-SubPc) thermally deposited on ITO substrate have been studied using admittance spectroscopic techniques. The I-V and capacitance -frequency (C-F) studies at various bias voltages reveal that the mobility of charge carriers decrease with bias voltage, however the conduction phenomenon still remain hopping in nature. From the differential susceptance curve, the contribution of the Schottky barrier contact in the charge carrier concentration was found to be absent. The mobility of charge carriers have been determined using differential susceptance variation and from the phase of admittance curve. The values obtained in two cases have been found to be in agreement with each other.

  17. Characterization and immunotherapeutic potential of a monoclonal antibody against a ras oncogene transformed cell line

    SciTech Connect

    Ames, R.S. Jr.

    1986-01-01

    Transformed cells express cell surface antigens not present, or present in diminished amounts on normal cells. Monoclonal antibodies can be used to identify and biochemically characterize tumor-associated antigens. Monoclonal antibody (MoAb) 45-2D9 was produced by immunization of BALB/c mice with a transformed cell line (45-2D9) induced by transfection of NIH 3T3 cells with a c-H-ras oncogene in DNA isolated from a human lung carcinoma. By immunoperoxidase staining, this antibody binds to the 45-342 cells as well as to the ras transformed primary and 3 secondary transfectants, including the one used to induce 45-342, but not to other ras transformed cell lines. Murine tumors as well as human fetal and most normal adult tissues are not stained. This antibody does bind to a variety of human tumors, including lung adenocarcinomas, as well as breast, colon and esophageal carcinomas. The ability of MoAb 45-2D9 to target ricin toxin A chain (RTA) and radio-isotopes to gp74 expressing cells was investigated. An immunotoxin generated by conjugating RTA to MoAb 45-2D9 inhibits protein and DNA synthesis by the 45-342 cells. Radiolabeled antibody specifically localizes to and can be used to image subcutaneous and pulmonary gp74 expressing tumors in nu/nu mice. Monoclonal antibodies against oncogene transformed cell lines may be useful for the detection and characterization of tumor-associated antigens as well as for the development of new tumor therapeutic and diagnostic reagents.

  18. Characterisation of defects in p-GaN by admittance spectroscopy

    NASA Astrophysics Data System (ADS)

    Elsherif, O. S.; Vernon-Parry, K. D.; Evans-Freeman, J. H.; Airey, R. J.; Kappers, M.; Humphreys, C. J.

    2012-08-01

    Mg-doped GaN films have been grown on (0 0 0 1) sapphire using metal organic vapour phase epitaxy. Use of different buffer layer strategies caused the threading dislocation density (TDD) in the GaN to be either approximately 2×109 cm-2 or 1×1010 cm-2. Frequency-dependent capacitance and conductance measurements at temperatures up to 450 K have been used to study the electronic states associated with the Mg doping, and to determine how these are affected by the TDD. Admittance spectroscopy of the films finds a single impurity-related acceptor level with an activation energy of 160±10 meV for [Mg] of about 1×1019 cm-3, and 120±10 eV as the Mg precursor flux decreased. This level is thought to be associated with the Mg acceptor state. The TDD has no discernible effect on the trap detected by admittance spectroscopy. We compare these results with cathodoluminescence measurements reported in the literature, which reveal that most threading dislocations are non-radiative recombination centres, and discuss possible reasons why our admittance spectroscopy have not detected electrically active defects associated with threading dislocations.

  19. Transient excitation and mechanical admittance test techniques for prediction of payload vibration environments

    NASA Technical Reports Server (NTRS)

    Kana, D. D.; Vargas, L. M.

    1977-01-01

    Transient excitation forces were applied separately to simple beam-and-mass launch vehicle and payload models to develop complex admittance functions for the interface and other appropriate points on the structures. These measured admittances were then analytically combined by a matrix representation to obtain a description of the coupled system dynamic characteristics. Response of the payload model to excitation of the launch vehicle model was predicted and compared with results measured on the combined models. These results are also compared with results of earlier work in which a similar procedure was employed except that steady-state sinusoidal excitation techniques were included. It is found that the method employing transient tests produces results that are better overall than the steady state methods. Furthermore, the transient method requires far less time to implement, and provides far better resolution in the data. However, the data acquisition and handling problem is more complex for this method. It is concluded that the transient test and admittance matrix prediction method can be a valuable tool for development of payload vibration tests.

  20. Left ventricular epicardial admittance measurement for detection of acute LV dilation

    PubMed Central

    Porterfield, John E.; Larson, Erik R.; Jenkins, James T.; Escobedo, Daniel; Valvano, Jonathan W.; Pearce, John A.

    2011-01-01

    There are two implanted heart failure warning systems incorporated into biventricular pacemakers/automatic implantable cardiac defibrillators and tested in clinical trials: right heart pressures, and lung conductance measurements. However, both warning systems postdate measures of the earliest indicator of impending heart failure: left ventricular (LV) volume. There are currently no proposed implanted technologies that can perform LV blood volume measurements in humans. We propose to solve this problem by incorporating an admittance measurement system onto currently deployed biventricular and automatic implantable cardiac defibrillator leads. This study will demonstrate that an admittance measurement system can detect LV blood conductance from the epicardial position, despite the current generating and sensing electrodes being in constant motion with the heart, and with dynamic removal of the myocardial component of the returning voltage signal. Specifically, in 11 pigs, it will be demonstrated that 1) a physiological LV blood conductance signal can be derived; 2) LV dilation in response to dose-response intravenous neosynephrine can be detected by blood conductance in a similar fashion to the standard of endocardial crystals when admittance is used, but not when only traditional conductance is used; 3) the physiological impact of acute left anterior descending coronary artery occlusion and resultant LV dilation can be detected by blood conductance, before the anticipated secondary rise in right ventricular systolic pressure; and 4) a pleural effusion simulated by placing saline outside the pericardium does not serve as a source of artifact for blood conductance measurements. PMID:21148342

  1. Characterization of genetically transformed Saccharomyces cerevisiae baker's yeasts able to metabolize melibiose.

    PubMed Central

    Gasent-Ramírez, J M; Codón, A C; Benítez, T

    1995-01-01

    Three transformant (Mel+) Saccharomyces cerevisiae baker's yeast strains, CT-Mel, VS-Mel, and DADI-Mel, have been characterized. The strains, which originally lacked alpha-galactosidase activity (Mel-), had been transformed with a DNA fragment which possessed an ILV1-SMR1 allele of the ILV2 gene and a MEL1 gene. The three transformed strains showed growth rates similar to those of the untransformed controls in both minimal and semi-industrial (molasses) media. The alpha-galactosidase specific activity of strain CT-Mel was twice that of VS-Mel and DADI-Mel. The yield, YX/S (milligrams of protein per milligram of substrate), in minimal medium with raffinose as the carbon source was 2.5 times higher in the transformed strains than in the controls and was 1.5 times higher in CT-Mel than in VS-Mel and DADI-Mel. When molasses was used, YX/S (milligrams of protein per milliliter of culture) increased 8% when the transformed strains CT-Mel and DADI-Mel were used instead of the controls. Whereas no viable spores were recovered from either DADI-Mel or VS-Mel tetrads, genetic analysis carried out with CT-Mel indicated that the MEL1 gene has been integrated in two of three homologous loci. Analysis of the DNA content by flow cytometry indicated that strain CT-Mel was 3n, whereas VS-Mel was 2n and DADI-Mel was 1.5n. Electrophoretic karyotype and Southern blot analyses of the transformed strains showed that the MEL1 gene has been integrated in the same chromosomic band, probably chromosome XIII, in the three strains.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7793932

  2. Admittance matrix of a trapezoidal piezoelectric heterogeneous bimorph.

    PubMed

    Schachtele, Jonathan; Goll, Erich; Muralt, Paul; Kaltenbacher, Dominik

    2012-12-01

    Bimorph structures are a standard method for transforming the high force of piezoelectric materials into a large deflection. In micro electromechanical systems (MEMS) applications, it is preferable to use structures consisting of a passive substrate (usually silicon) and one or more piezoelectric layers on the top. Such structures are called heterogeneous bimorphs or enakemesomorphs. In some MEMS applications- for example, for use as acoustic transducers-it is desirable to arrange such heterogeneous bimorphs in a circular shape, which results in trapezoidal cantilever structures. In this paper, an analytic dynamic description of such actuators is obtained. The resulting model is proved to be compatible with existing models for heterogeneous bimorphs with constant width. A comparison to a finite element analysis model of an exemplary layout shows divergences wholly within the same range as found for published models for constant-width structures. PMID:23221226

  3. Microstructural characterization of transformable Fe-Mn alloys at different length scales

    SciTech Connect

    Liang, X.; Wang, X.; Zurob, H.S.

    2009-11-15

    The as-annealed and deformed Microstructure of transformable Fe-Mn alloys were, comprehensively, characterized over a wide range of length scales. Differential interference contrast optical metallography, combined with a tinting etching method, was employed to examine the grain morphology. A new specimen preparation method, involving electro-polishing and electro-etching, was developed for scanning electron microscopy and electron back-scattered diffraction analysis. This method leads to a very good imaging contrast and thus bridges the length scale gap between optical metallography and transmission electron microscopy. Moreover, it enables simultaneous scanning electron microscopy and electron backscatter diffraction analysis which allows correlations among morphology, crystal orientation and phase analysis in the length scale of microns. Transmission electron microscopy investigations were also made to evaluate the thermal and mechanical transformation products as well as defect structures.

  4. Characterization of a case of follicular lymphoma transformed into B-lymphoblastic leukemia

    PubMed Central

    2013-01-01

    Follicular lymphoma (FL) is a common form of non-Hodgkin lymphoma with an ability to transform into a more aggressive disease, albeit infrequently to B-lymphoblastic leukemia/lymphoma. While t(14;18)(q32;q21) has been associated with approximately 90% cases of FL, that alteration alone is insufficient to cause FL and associated mutations are still being elucidated. The transformation of FL to B-lymphoblastic leukemia generally includes the dysregulation of MYC gene expression, typically through IGH rearrangement. Such cases of “double-hit” leukemia/lymphoma with both BCL2 and MYC translocations warrant further study as they are often not identified early, are associated with a poor prognosis, and are incompletely understood in molecular terms. Here we describe a patient with a diagnosis of FL that transformed to B-lymphoblastic leukemia. Detailed cytogenetic characterization of the transformed specimen using karyotype, fluorescence in situ hybridization, microarray and gene rearrangement analyses revealed a complex karyotype comprised principally of whole chromosome or whole arm copy number gains or losses. Smaller, single-gene copy number alterations identified by microarray were limited in number, but included amplification of a truncated EP300 gene and alterations in NEIL1 and GPHN. Analyses defined the presence of an IGH/BCL2 fusion due to a translocation as well as a MYC/IGH fusion due to an insertion, with both rearrangements involving the same IGH allele. The data illustrate the value in characterizing double-hit lymphoma cases with both traditional and novel technologies in the detailed cytogenetic workup. PMID:23985173

  5. Malignant Transformation of a Dysembryoplastic Neuroepithelial Tumor (DNET) Characterized by Genome-Wide Methylation Analysis.

    PubMed

    Heiland, Dieter Henrik; Staszewski, Ori; Hirsch, Martin; Masalha, Waseem; Franco, Pamela; Grauvogel, Jürgen; Capper, David; Schrimpf, Daniel; Urbach, Horst; Weyerbrock, Astrid

    2016-04-01

    Dysembryoplastic neuroepithelial tumors (DNET) are considered to be rare, benign, and associated with chronic epilepsy. We present the case of a 28-year-old man with a history of epilepsy since age 12. Surgery of an occipital cortical lesion in 2009 revealed a DNET. Five years later, a recurrent tumor at the edge of the resection cavity was removed, and the tissue underwent an intensive diagnostic workup. The first tumor was unequivocally characterized as a DNET, but neuropathological diagnostics of the recurrent tumor revealed a glioblastoma. After 6 months, another recurrent tumor was detected next to the location of the original tumor, and this was also resected. An Illumina 450 K beadchip methylation array was performed to characterize all of the tumors. The methylation profile of these tumors significantly differed from other glioblastoma and epilepsy-associated tumor profiles and revealed a DNET-like methylation profile. Thus, molecular characterization of these recurrent tumors suggests malignant transformation of a previously benign DNET. We found increased copy number changes in the recurrent DNET tumors after malignant transformation. Modern high-throughput analysis adds essential molecular information in addition to standard histopathology for proper identification of rare brain tumors that present with an unusual clinical course. PMID:26921879

  6. Characterization of near-millimeter wave materials by means of non-dispersive Fourier transform spectroscopy

    NASA Astrophysics Data System (ADS)

    Simonis, G. J.; Sattler, J. P.; Worchesky, T. L.; Leavitt, R. P.

    1984-01-01

    Nondispersive Fourier-transform-spectroscopic techniques are used to measure the complex indices of refraction of materials between frequencies of 120 and 550 GHz. Results are presented for crystal quartz, cross-linked polystyrene (Rexolite 1422), glass-loaded polytetrafluoroethylene (Duroid 5880) and a nickel ferrite (Trans-Tech 2-111). These results are compared with other data on these materials in this frequency range. The accuracy of these measurements yields a considerable improvement in the near-millimeter-wave characterization of several of these materials. For materials other than crystal quartz, the results are the first measurements of their properties over the entire frequency range studied.

  7. Characterization of Solid State Phase Transformation in Continuously Heated and Cooled Ferritic Weld Metal

    SciTech Connect

    Narayana, B; Mills, Michael J.; Specht, Eliot D; Santella, Michael L; Babu, Sudarsanam Suresh

    2010-12-01

    Arc welding processes involve cooling rates that vary over a wide range (1-100 K/s). The final microstructire is thus a product of the heating and cooling cycles experienced by the weld in addition to the weld composition. It has been shown that the first phase to form under weld cooling conditions may not be that predicted by equilibrium calculations. The partitioning of different interstitial/substitutional alloying elements at high temperatures can dramatically affect the subsequent phase transformations. In order to understand the effect of alloying on phase transformation temperatures and final microstructures time-resolved X-ray diffraction technique has been successfully used for characterization. The work by Jacot and Rappaz on pearlitic steels provided insight into austenitization of hypoeutectic steels using a finite volume model. However there is very little work done on the effect of heating and cooling rates on the phase transformation paths in bainitic/martensitic steels and weld metals. Previous work on a weld with higher aluminum content, deposited with a FCAW-S process indicated that even at aluminum levels where the primary phase to solidify from liquid should be delta ferrite, non-equilibrium austenite was observed. The presence of inhomogeneity in composition of the parent microstructure has been attributed to differences in transformation modes, temperatures and microstructures in dual-phase, TRIP steels and ferritic welds. The objectives of the work included the identification of the stability regions of different phases during heating and cooling, differences in the effect of weld heating and cooling rates on the phase transformation temperatures, and the variation in phase fractions of austenite and ferrite in the two phase regions as a function of temperature. The base composition used for the present work is a Fe-1%Al-2%Mn-1%Ni-0.04%C weld metal. A pseudo-binary phase diagram shows the expected solidification path under equilibrium

  8. Observation of lower defect density in CH3NH3Pb(I,Cl)3 solar cells by admittance spectroscopy

    NASA Astrophysics Data System (ADS)

    Jiang, Minlin; Lan, Fei; Zhao, Bingxin; Tao, Quan; Wu, Jiamin; Gao, Di; Li, Guangyong

    2016-06-01

    The introduction of Cl into CH3NH3PbI3 precursors is reported to enhance the performance of CH3NH3PbI3 solar cell, which is attributed to the significantly increased diffusion lengths of carriers in CH3NH3Pb(I,Cl)3 solar cell. It has been assumed but never experimentally approved that the defect density in CH3NH3Pb(I,Cl)3 solar cell should be reduced according to the higher carrier lifetime observed from photoluminescence (PL) measurement. We have fabricated CH3NH3Pb(I,Cl)3 solar cell by adding a small amount of Cl source into CH3NH3PbI3 precursor. The performance of CH3NH3Pb(I,Cl)3 solar cell is significantly improved from 15.39% to 18.60%. Results from scanning electron microscopy and X-ray diffraction indicate that the morphologies and crystal structures of CH3NH3PbI3 and CH3NH3Pb(I,Cl)3 thin films remain unchanged. Open circuit voltage decay and admittance spectroscopy characterization jointly approve that Cl plays an extremely important role in suppressing the formation of defects in perovskite solar cells.

  9. Multidimensional orthogonal filter bank characterization and design using the Cayley transform.

    PubMed

    Zhou, Jianping; Do, Minh N; Kovacević, Jelena

    2005-06-01

    We present a complete characterization and design of orthogonal infinite impulse response (IIR) and finite impulse response (FIR) filter banks in any dimension using the Cayley transform (CT). Traditional design methods for one-dimensional orthogonal filter banks cannot be extended to higher dimensions directly due to the lack of a multidimensional (MD) spectral factorization theorem. In the polyphase domain, orthogonal filter banks are equivalent to paraunitary matrices and lead to solving a set of nonlinear equations. The CT establishes a one-to-one mapping between paraunitary matrices and para-skew-Hermitian matrices. In contrast to the paraunitary condition, the para-skew-Hermitian condition amounts to linear constraints on the matrix entries which are much easier to solve. Based on this characterization, we propose efficient methods to design MD orthogonal filter banks and present new design results for both IIR and FIR cases. PMID:15971775

  10. Characterization of coarse bainite transformation in low carbon steel during simulated welding thermal cycles

    SciTech Connect

    Lan, Liangyun; Kong, Xiangwei; Qiu, Chunlin

    2015-07-15

    Coarse austenite to bainite transformation in low carbon steel under simulated welding thermal cycles was morphologically and crystallographically characterized by means of optical microscope, transmission electron microscope and electron backscattered diffraction technology. The results showed that the main microstructure changes from a mixture of lath martensite and bainitic ferrite to granular bainite with the increase in cooling time. The width of bainitic laths also increases gradually with the cooling time. For a welding thermal cycle with relatively short cooling time (e.g. t{sub 8/5} is 30 s), the main mode of variant grouping at the scale of individual prior austenite grains changes from Bain grouping to close-packed plane grouping with the progress of phase transformation, which results in inhomogeneous distribution of high angle boundaries. As the cooling time is increased, the Bain grouping of variants becomes predominant mode, which enlarges the effective grain size of product phase. - Highlights: • Main microstructure changes and the width of lath structure increases with cooling time. • Variant grouping changes from Bain zone to close-packed plane grouping with the transformation. • The change of variant grouping results in uneven distribution of high angle grain boundary. • Bain grouping is main mode for large heat input, which lowers the density of high angle boundary.

  11. Dependence of electric current through human body on parameters of 3-0 network in range of high insulation admittance

    NASA Astrophysics Data System (ADS)

    Motuzko, F. Y.; Trubitsyn, A. V.

    1985-04-01

    The electric current I sub h through a human body touching one phase of a 3-0 network is calculated on the basis of the conventional equivalent circuit for the general case of unequal insulation admittances in all three phases. The two extreme cases here are all three insulation admittances approaching zero or infinity respectively. The theoretical relation in the latter case is not consistent with reality, in which an infinitely large insulation admittance presents a short circuit across the 3-0 source and a fully effective shunt across the human body. The equivalent circuit is modified, accordingly, to include the internal source resistance in series with the insulation admittance in each phase. Calculations pertaining to the method of personnel protection are continued, to establish the dependence of current on the insulation resistance of the touched phase and thus establish the safe range of this resistance when the resistance as well as the insulation admittance of this phase are different from those of the other two phases and those of the other two phases are equal.

  12. Real time pressure-volume loops in mice using complex admittance: measurement and implications.

    PubMed

    Kottam, Anil T G; Porterfield, John; Raghavan, Karthik; Fernandez, Daniel; Feldman, Marc D; Valvano, Jonathan W; Pearce, John A

    2006-01-01

    Real time left ventricular (LV) pressure-volume (P-V) loops have provided a framework for understanding cardiac mechanics in experimental animals and humans. Conductance measurements have been used for the past 25 years to generate an instantaneous left ventricular (LV) volume signal. The standard conductance method yields a combination of blood and ventricular muscle conductance; however, only the blood signal is used to estimate LV volume. The state of the art techniques like hypertonic saline injection and IVC occlusion, determine only a single steady-state value of the parallel conductance of the cardiac muscle. This is inaccurate, since the cardiac muscle component should vary instantaneously throughout the cardiac cycle as the LV contracts and fills, because the distance from the catheter to the muscle changes. The capacitive nature of cardiac muscle can be used to identify its contribution to the combined conductance signal. This method, in contrast to existing techniques, yields an instantaneous estimate of the parallel admittance of cardiac muscle that can be used to correct the measurement in real time. The corrected signal consists of blood conductance alone. We present the results of real time in vivo measurements of pressure-admittance and pressure-phase loops inside the murine left ventricle. We then use the magnitude and phase angle of the measured admittance to determine pressure volume loops inside the LV on a beat by beat basis. These results may be used to achieve a substantial improvement in the state of the art in this measurement method by eliminating the need for hypertonic saline injection. PMID:17946238

  13. Admittance Test and Conceptual Study of a CW Positron Source for CEBAF

    SciTech Connect

    Golge, Serkan; Hyde, Charles E.; Freyberger, Arne

    2009-09-02

    A conceptual study of a Continuous Wave (CW) positron production is presented in this paper. The Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (JLAB) operates with a CW electron beam with a well-defined emittance, time structure and energy spread. Positrons created via bremsstrahlung photons in a high-Z target emerge with a large emittance compared to incoming electron beam. An admittance study has been performed at CEBAF to estimate the maximum beam phase space area that can be transported in the LINAC and in the Arcs. A positron source is described utilizing the CEBAF injector electron beam, and directly injecting the positrons into the CEBAF LINAC.

  14. Measuring the complex admittance of a nearly isolated graphene quantum dot

    SciTech Connect

    Zhang, Miao-Lei; Wei, Da; Deng, Guang-Wei; Li, Shu-Xiao; Li, Hai-Ou; Cao, Gang; Tu, Tao; Xiao, Ming; Guo, Guang-Can; Guo, Guo-Ping; Jiang, Hong-Wen

    2014-08-18

    We measured the radio-frequency reflection spectrum of an on-chip reflection line resonator coupled to a graphene double quantum dot (DQD), which was etched almost isolated from the reservoir and reached the low tunnel rate region. The charge stability diagram of DQD was investigated via dispersive phase and magnitude shift of the resonator with a high quality factor. Its complex admittance and low tunnel rate to the reservoir was also determined from the reflected signal of the on-chip resonator. Our method may provide a non-invasive and sensitive way of charge state readout in isolated quantum dots.

  15. Dynamic virtual fixture on the Euclidean group for admittance-type manipulator in deforming environments

    PubMed Central

    2014-01-01

    Background In a deforming anatomic environment, the motion of an instrument suffers from complex geometrical and dynamic constraints, robot assisted minimally invasive surgery therefore requires more sophisticated skills for surgeons. This paper proposes a novel dynamic virtual fixture (DVF) to enhance the surgical operation accuracy of admittance-type medical robotics in the deforming environment. Methods A framework for DVF on the Euclidean Group SE(3) is presented, which unites rotation and translation in a compact form. First, we constructed the holonomic/non-holonomic constraints, and then searched for the corresponded reference to make a distinction between preferred and non-preferred directions. Second, different control strategies are employed to deal with the tasks along the distinguished directions. The desired spatial compliance matrix is synthesized from an allowable motion screw set to filter out the task unrelated components from manual input, the operator has complete control over the preferred directions; while the relative motion between the surgical instrument and the anatomy structures is actively tracked and cancelled, the deviation relative to the reference is compensated jointly by the operator and DVF controllers. The operator, haptic device, admittance-type proxy and virtual deforming environment are involved in a hardware-in-the-loop experiment, human-robot cooperation with the assistance of DVF controller is carried out on a deforming sphere to simulate beating heart surgery, performance of the proposed DVF on admittance-type proxy is evaluated, and both human factors and control parameters are analyzed. Results The DVF can improve the dynamic properties of human-robot cooperation in a low-frequency (0 ~ 40 rad/sec) deforming environment, and maintain synergy of orientation and translation during the operation. Statistical analysis reveals that the operator has intuitive control over the preferred directions, human and the DVF

  16. Accurate determination of interface trap state parameters by admittance spectroscopy in the presence of a Schottky barrier contact: Application to ZnO-based solar cells

    NASA Astrophysics Data System (ADS)

    Marin, Andrew T.; Musselman, Kevin P.; MacManus-Driscoll, Judith L.

    2013-04-01

    This work shows that when a Schottky barrier is present in a photovoltaic device, such as in a device with an ITO/ZnO contact, equivalent circuit analysis must be performed with admittance spectroscopy to accurately determine the pn junction interface recombination parameters (i.e., capture cross section and density of trap states). Without equivalent circuit analysis, a Schottky barrier can produce an error of ˜4-orders of magnitude in the capture cross section and ˜50% error in the measured density of trap states. Using a solution processed ZnO/Cu2O photovoltaic test system, we apply our analysis to clearly separate the contributions of interface states at the pn junction from the Schottky barrier at the ITO/ZnO contact so that the interface state recombination parameters can be accurately characterized. This work is widely applicable to the multitude of photovoltaic devices, which use ZnO adjacent to ITO.

  17. Compound specific stable isotope analysis (CSIA) to characterize transformation mechanisms of α-hexachlorocyclohexane.

    PubMed

    Zhang, Ning; Bashir, Safdar; Qin, Jinyi; Schindelka, Janine; Fischer, Anko; Nijenhuis, Ivonne; Herrmann, Hartmut; Wick, Lukas Y; Richnow, Hans H

    2014-09-15

    A systematic investigation of environmentally relevant transformation processes of alpha-hexachlorocyclohexane (α-HCH) was performed in order to explore the potential of compound specific stable isotope analysis (CSIA) to characterize reaction mechanisms. The carbon isotope enrichment factors (ɛC) for the chemical transformations of α-HCH via direct photolysis, indirect photolysis (UV/H2O2), hydrolysis, electro-reduction or reduction by Fe(0) were quantified and compared to those previously published for biodegradation. Hydrogen abstraction by hydroxyl radicals generated by UV/H2O2 led to ɛC of -1.9 ± 0.2 ‰ with an apparent kinetic carbon isotope effect (AKIEC) of 1.012 ± 0.001. Dehydrochlorination by alkaline hydrolysis yielded ɛC of -7.6 ± 0.4 ‰ with AKIEC of 1.048 ± 0.003. Dechlorination either by homolytic bond cleavage in direct photolysis (ɛC=-2.8 ± 0.2 ‰) or single-electron transfer in electro-reduction (ɛC=-3.8 ± 0.4 ‰) corresponded to AKIEC of 1.017 ± 0.001 and 1.023 ± 0.003, respectively. Dichloroelimination catalyzed by Fe(0) via two-electron transfers resulted in ɛC of -4.9 ± 0.1 ‰. AKIEC values assuming either a concerted or a stepwise mechanism were 1.030 ± 0.0006 and 1.015 ± 0.0003, respectively. Contrary to biodegradation, no enantioselectivity of α-HCH was observed in chemical reactions, which might be used to discriminate chemical and biological in situ transformations. PMID:25238192

  18. Glycosaminoglycan Characterization by Electrospray Ionization Mass Spectrometry Including Fourier Transform Mass Spectrometry

    PubMed Central

    Laremore, Tatiana N.; Leach, Franklin E.; Solakyildirim, Kemal; Amster, I. Jonathan; Linhardt, Robert J.

    2011-01-01

    Electrospray ionization mass spectrometry (ESI MS) is a versatile analytical technique in glycomics of glycosaminoglycans (GAGs). Combined with enzymology, ESI MS is used for assessing changes in disaccharide composition of GAGs biosynthesized under different environmental or physiological conditions. ESI coupled with high-resolution mass analyzers such as a Fourier transform mass spectrometer (FTMS) permits accurate mass measurement of large oligosaccharides and intact GAGs as well as structural characterization of GAG oligosaccharides using information-rich fragmentation methods such as electron detachment dissociation. The first part of this chapter describes methods for disaccharide compositional profiling using ESI MS and the second part is dedicated to FTMS and tandem MS methods of GAG compositional and structural analysis. PMID:20816475

  19. Multiscale characterization method for line edge roughness based on redundant second generation wavelet transform

    SciTech Connect

    Wang Fei; Zhao Xuezeng; Li Ning

    2010-10-15

    We introduce a multiscale characterization method for line edge roughness (LER) based on redundant second generation wavelet transform. This method involves decomposing LER characteristics into independent bands with different spatial frequency components at different scales, and analyzing the reconstructed signals to work out the roughness exponent, the spatial frequency distribution characteristics, as well as the rms value. The effect of noise can be predicted using detailed signals in the minimum space of scale. This method was applied to numerical profiles for validation. Results show that according to the line edge profiles with similar amplitudes, the roughness exponent R can effectively reflect the degree of irregularity of LER and intuitively provide information on LER spatial frequency distribution.

  20. Localized Gravity/Topography Admittance and Correlation Spectra on Mars: Implications for Regional and Global Evolution

    NASA Technical Reports Server (NTRS)

    McGovern, Patrick J.; Solomon, Sean C.; Smith, David E.; Zuber, Maria T.; Simons, Mark; Wieczorek, Mark A.; Phillips, Roger J.; Neumann, Gregory A.; Aharonson, Oded; Head, James W.

    2002-01-01

    [i] From gravity and topography data collected by the Mars Global Surveyor spacecraft we calculate gravity/topography admittances and correlations in the spectral domain and compare them to those predicted from models of lithospheric flexure. On the basis of these comparisons we estimate the thickness of the Martian elastic lithosphere (T(sub e)) required to support the observed topographic load since the time of loading. We convert T(sub e) to estimates of heat flux and thermal gradient in the lithosphere through a consideration of the response of an elastic/plastic shell. In regions of high topography on Mars (e.g., the Tharsis rise and associated shield volcanoes), the mass-sheet (small-amplitude) approximation for the calculation of gravity from topography is inadequate. A correction that accounts for finite-amplitude topography tends to increase the amplitude of the predicted gravity signal at spacecraft altitudes. Proper implementation of this correction requires the use of radii from the center of mass (collectively known as the planetary shape ) in lieu of topography referenced to a gravitational equipotential. Anomalously dense surface layers or buried excess masses are not required to explain the observed admittances for the Tharsis Montes or Olympus Mons volcanoes when this correction is applied. Derived T, values generally decrease with increasing age of the lithospheric load, in a manner consistent with a rapid decline of mantle heat flux during the Noachian and more modest rates of decline during subsequent epochs.

  1. Hole transport characteristics in phosphorescent dye-doped NPB films by admittance spectroscopy

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Chen, Jiangshan; Huang, Jinying; Dai, Yanfeng; Zhang, Zhiqiang; Liu, Su; Ma, Dongge

    2014-05-01

    Admittance spectroscopy is a powerful tool to determine the carrier mobility. The carrier mobility is a significant parameter to understand the behavior or to optimize the organic light-emitting diode or other organic semiconductor devices. Hole transport in phosphorescent dye, bis[2-(9,9-diethyl-9H-fluoren-2-yl)-1-phenyl-1Hbenzoimidazol-N,C3] iridium(acetylacetonate [(fbi)2Ir(acac)]) doped into N,N-diphenyl-N,N-bis(1-naphthylphenyl)-1,1-biphenyl-4,4-diamine (NPB) films was investigated by admittance spectroscopy. The results show that doped (fbi)2Ir(acac) molecules behave as hole traps in NPB, and lower the hole mobility. For thicker films(≳300 nm), the electric field dependence of hole mobility is as expected positive, i.e., the mobility increases exponentially with the electric field. However, for thinner films (≲300 nm), the electric field dependence of hole mobility is negative, i.e., the hole mobility decreases exponentially with the electric field. Physical mechanisms behind the negative field dependence of hole mobility are discussed. In addition, three frequency regions were divided to analyze the behaviors of the capacitance in the hole-only device and the physical mechanism was explained by trap theory and the parasitic capacitance effect.

  2. Distortion product otoacoustic emission suppression tuning and acoustic admittance in human infants: Birth through 6 months

    PubMed Central

    Abdala, Carolina; Keefe, Douglas H.; Oba, Sandra I.

    2009-01-01

    Previous work has reported non-adultlike distortion product otoacoustic emission (DPOAE) suppression in human newborns at f2 =6000 Hz, indicating an immaturity in peripheral auditory function. In this study, DPOAE suppression tuning curves (STCs) were recorded as a measure of cochlear function and acoustic admittance/reflectance (YR) in the ear canal recorded as a measure of middle-ear function, in the same 20 infants at birth and through 6 months of age. DPOAE STCs changed little from birth through 6 months, showing excessively narrow and sharp tuning throughout the test period. In contrast, several middle-ear indices at corresponding frequencies shifted systematically with increasing age, although they also remained non-adultlike at 6 months. Linear correlations were conducted between YR and DPOAE suppression features. Only two correlations out of 76 were significant, and all but three YR variables accounted for <10% of the variance in DPOAE suppression tuning. The strongest correlation was noted between admittance phase at 5700 Hz and STC tip-to-tail (R=0.49). The association between middle-ear variables and DPOAE suppression may be stronger during other developmental time periods. Study of older infants and children is needed to fully define postnatal immaturity of human peripheral auditory function. PMID:17552713

  3. Transformation twinning of Ni–Mn–Ga characterized with temperature-controlled atomic force microscopy

    PubMed Central

    Reinhold, Matthew; Watson, Chad; Knowlton, William B.; Müllner, Peter

    2010-01-01

    The magnetomechanical properties of ferromagnetic shape memory alloy Ni–Mn–Ga single crystals depend strongly on the twin microstructure, which can be modified through thermomagnetomechanical training. Atomic force microscopy (AFM) and magnetic force microscopy (MFM) were used to characterize the evolution of twin microstructures during thermomechanical training of a Ni–Mn–Ga single crystal. Experiments were performed in the martensite phase at 25 °C and in the austenite phase at 55 °C. Two distinct twinning surface reliefs were observed at room temperature. At elevated temperature (55 °C), the surface relief of one twinning mode disappeared while the other relief remained unchanged. When cooled back to 25 °C, the twin surface relief recovered. The relief persisting at elevated temperature specifies the positions of twin boundaries that were present when the sample was polished prior to surface characterization. AFM and MFM following thermomechanical treatment provide a nondestructive method to identify the crystallographic orientation of each twin and of each twin boundary plane. Temperature dependent AFM and MFM experiments reveal the twinning history thereby establishing the technique as a unique predictive tool for revealing the path of the martensitic and reverse transformations of magnetic shape memory alloys. PMID:20589105

  4. Characterizing and overcoming spectral artifacts in imaging Fourier-transform spectroscopy of turbulent exhaust plumes

    NASA Astrophysics Data System (ADS)

    Moore, Elizabeth A.; Gross, Kevin C.; Bowen, Spencer J.; Perram, Glen P.; Chamberland, Martin; Farley, Vincent; Gagnon, Jean-Philippe; Lagueux, Philippe; Villemaire, André

    2009-05-01

    The midwave and shortwave infrared regions of the electromagnetic spectrum contain rich information enabling the characterization of hot, rapid events such as explosions, engine plumes, flares and other combustion events. High-speed sensors are required to analyze the content of such rapidly evolving targets. Cameras with high frame rates and non-imaging spectrometers with high data rates are typically used; however the information from these two types of instruments must be later fused to enable characterization of the transient targets. Imaging spectrometers have recently become commercially available for general scientific use, thus enabling simultaneous capture of both spatial and spectral information without co-registration issues. However, their use against rapidly-varying sources has traditionally been considered problematic, for even at moderate spatial and spectral resolutions the time to acquire a single spectrum can be long compared to the timescales associated with combustion events. This paper demonstrates that imaging Fourier-transform spectroscopy (IFTS) can successfully characterize the turbulent combustion exhaust from a turbojet engine. A Telops Hyper-Cam IFTS collected hyperspectral video from a Turbine Technologies SR-30 turbojet engine with a spectral resolution of δν = 1/cm-1 on a 200×64 pixel sub-window at a rate of 0.3 Hz. Scene-change artifacts (SCAs) are present in the spectra; however, the stochastic fluctuations in source intensity translate into high-frequency "noise." Temporal averaging affords a significant reduction of the noise associated with SCAs. Emission from CO and CO2 are clearly recognized in the averaged spectra, and information about their temperature and relative concentrations is evident.

  5. The HCP To BCC Phase Transformation in Ti Characterized by Nanosecond Electron Microscopy

    SciTech Connect

    Campbell, G; LaGrange, T; King, W; Colvin, J; Ziegler, A; Browning, N; Kleinschmidt, H; Bostanjoglo, O

    2005-06-21

    The general class of martensitic phase transformations occurs by a rapid lattice-distortive mechanism, where kinetics and morphology of the transformation are dominated by the strain energy. Since transformation is diffusionless, phase fronts propagate through a crystal with great speed that can approach the speed of sound. We have observed a particular example of this class of phase transformation, the hexagonal close packed (HCP) to body centered cubic (BCC) transformation in titanium that is driven by a rapid increase in temperature. We have used a novel nanosecond electron microscope (the dynamic transmission electron microscope, DTEM) to acquire diffraction and imaging information on the transformation, which is driven in-situ by nanosecond laser irradiation. Using nanosecond exposure times that are possible in the DTEM, data can be collected about the transient events in these fast transformations. We have identified the phase transformation with diffraction patterns and correlated the time of the phase transformation with calculated conditions in the sample.

  6. In Situ Focused Beam Reflectance Measurement (FBRM), Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and Raman Characterization of the Polymorphic Transformation of Carbamazepine

    PubMed Central

    Zhao, Yingying; Bao, Ying; Wang, Jingkang; Rohani, Sohrab

    2012-01-01

    The objective of this work was to study the polymorphic transformation of carbamazepine from Form II to Form III in 1-propanol during seeded isothermal batch crystallization. First, the pure Form II and Form III were obtained and characterized. Then their solubilities and metastable zone limits were measured by in-situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and focused beam reflectance measurement (FBRM). A transition temperature at about 34.2 °C was deduced suggesting the enantiotropic nature of this compound over the studied temperature range. To quantify the polymorph ratio during the transformation process, a new in-situ quantitative method was developed to measure the fraction of Form II by Raman spectroscopy. Successful tracking of the nucleation of the stable form and the transformation from Form II to Form III during isothermal crystallization was achieved by Raman spectroscopy and FBRM. The results from these three in-situ techniques, FBRM, FTIR and Raman were consistent with each other. The results showed a strong dependency on the amount of seeds added during isothermal crystallization. PMID:24300186

  7. Sixteen-Year Change in Acoustic-Admittance Measures among Older Adults: Data from a Population-Based Study

    ERIC Educational Resources Information Center

    Nondahl, David M.; Cruickshanks, Karen J.; Wiley, Terry L.; Tweed, Ted S.; Dalton, Dayna S.

    2013-01-01

    Purpose: The primary purpose of this study was to measure the 16-year change in peak compensated static acoustic admittance (Peak Y[subscript tm]) in a population-based cohort of older adults, and to determine whether age was associated with any observed change in Peak Y[subscript tm]. Other tympanometric measures also were taken and analyzed.…

  8. Chinchilla middle-ear admittance and sound power: High-frequency estimates and effects of inner-ear modifications

    PubMed Central

    Ravicz, Michael E.; Rosowski, John J.

    2012-01-01

    The middle-ear input admittance relates sound power into the middle ear (ME) and sound pressure at the tympanic membrane (TM). ME input admittance was measured in the chinchilla ear canal as part of a larger study of sound power transmission through the ME into the inner ear. The middle ear was open, and the inner ear was intact or modified with small sensors inserted into the vestibule near the cochlear base. A simple model of the chinchilla ear canal, based on ear canal sound pressure measurements at two points along the canal and an assumption of plane-wave propagation, enables reliable estimates of YTM, the ME input admittance at the TM, from the admittance measured relatively far from the TM. YTM appears valid at frequencies as high as 17 kHz, a much higher frequency than previously reported. The real part of YTM decreases with frequency above 2 kHz. Effects of the inner-ear sensors (necessary for inner ear power computation) were small and generally limited to frequencies below 3 kHz. Computed power reflectance was ∼0.1 below 3.5 kHz, lower than with an intact ME below 2.5 kHz, and nearly 1 above 16 kHz. PMID:23039439

  9. The effect of flying and low humidity on the admittance of the tympanic membrane and middle ear system.

    PubMed

    Morse, Robert Peter

    2013-10-01

    Many passengers experience discomfort during flight because of the effect of low humidity on the skin, eyes, throat, and nose. In this physiological study, we have investigated whether flight and low humidity also affect the tympanic membrane. From previous studies, a decrease in admittance of the tympanic membrane through drying might be expected to affect the buffering capacity of the middle ear and to disrupt automatic pressure regulation. This investigation involved an observational study onboard an aircraft combined with experiments in an environmental chamber, where the humidity could be controlled but could not be made to be as low as during flight. For the flight study, there was a linear relationship between the peak compensated static admittance of the tympanic membrane and relative humidity with a constant of proportionality of 0.00315 mmho/% relative humidity. The low humidity at cruise altitude (minimum 22.7 %) was associated with a mean decrease in admittance of about 20 % compared with measures in the airport. From the chamber study, we further found that a mean decrease in relative humidity of 23.4 % led to a significant decrease in mean admittance by 0.11 mmho [F(1,8) = 18.95, P = 0.002], a decrease of 9.4 %. The order of magnitude for the effect of humidity was similar for the flight and environmental chamber studies. We conclude that admittance changes during flight were likely to have been caused by the low humidity in the aircraft cabin and that these changes may affect the automatic pressure regulation of the middle ear during descent. PMID:23887775

  10. Admittance Investigation of MIS Structures with HgTe-Based Single Quantum Wells

    NASA Astrophysics Data System (ADS)

    Izhnin, Ihor I.; Nesmelov, Sergey N.; Dzyadukh, Stanislav M.; Voitsekhovskii, Alexander V.; Gorn, Dmitry I.; Dvoretsky, Sergey A.; Mikhailov, Nikolaj N.

    2016-02-01

    This work presents results of the investigation of admittance of metal-insulator-semiconductor structure based on Hg1 - x Cd x Te grown by molecular beam epitaxy. The structure contains a single quantum well Hg0.35Cd0.65Te/HgTe/Hg0.35Cd0.65Te with thickness of 5.6 nm in the sub-surface layer of the semiconductor. Both the conductance-voltage and capacitance-voltage characteristics show strong oscillations when the metal-insulator-semiconductor (MIS) structure with a single quantum well based on HgTe is biased into the strong inversion mode. Also, oscillations on the voltage dependencies of differential resistance of the space charge region were observed. These oscillations were related to the recharging of quantum levels in HgTe.

  11. Quantum dot admittance probed at microwave frequencies with an on-chip resonator

    NASA Astrophysics Data System (ADS)

    Frey, T.; Leek, P. J.; Beck, M.; Faist, J.; Wallraff, A.; Ensslin, K.; Ihn, T.; Büttiker, M.

    2012-09-01

    We present microwave frequency measurements of the dynamic admittance of a quantum dot tunnel-coupled to a two-dimensional electron gas. The measurements are made via a high-quality 6.75 GHz on-chip resonator capacitively coupled to the dot. The resonator frequency is found to shift both down and up close to conductance resonance of the dot corresponding to a change of sign of the reactance of the system from capacitive to inductive. The observations are consistent with a scattering matrix model. The sign of the reactance depends on the detuning of the dot from conductance resonance and on the magnitude of the tunnel rate to the lead with respect to the resonator frequency. Inductive response is observed on a conductance resonance when tunnel coupling and temperature are sufficiently small compared to the resonator frequency.

  12. Three-dimensional admittance analysis of lithospheric elastic thickness over the Louisville Ridge

    NASA Astrophysics Data System (ADS)

    Hu, Minzhang; Li, Hui; Shen, Chongyang; Xing, Lelin; Hao, Hongtao

    2016-04-01

    Using bathymetry and altimetric gravity anomalies, a 1° × 1° lithospheric effective elastic thickness ( T e) model over the Louisville Ridge and its adjacent regions is calculated using the moving window admittance technique. For comparison, three bathymetry models are used: general bathymetric charts of the oceans, SIO V15.1, and BAT_VGG. The results show that BAT_VGG is more suitable for calculating T e than the other two models. T e along the Louisville Ridge was re-evaluated. The southeast of the ridge has a medium T e of 10-20 km, while T e increases dramatically seaward of the Tonga-Kermadec trench as a result of the collision of the Pacific and Indo-Australian plates.

  13. Admittance Investigation of MIS Structures with HgTe-Based Single Quantum Wells.

    PubMed

    Izhnin, Ihor I; Nesmelov, Sergey N; Dzyadukh, Stanislav M; Voitsekhovskii, Alexander V; Gorn, Dmitry I; Dvoretsky, Sergey A; Mikhailov, Nikolaj N

    2016-12-01

    This work presents results of the investigation of admittance of metal-insulator-semiconductor structure based on Hg1 - x Cd x Te grown by molecular beam epitaxy. The structure contains a single quantum well Hg0.35Cd0.65Te/HgTe/Hg0.35Cd0.65Te with thickness of 5.6 nm in the sub-surface layer of the semiconductor. Both the conductance-voltage and capacitance-voltage characteristics show strong oscillations when the metal-insulator-semiconductor (MIS) structure with a single quantum well based on HgTe is biased into the strong inversion mode. Also, oscillations on the voltage dependencies of differential resistance of the space charge region were observed. These oscillations were related to the recharging of quantum levels in HgTe. PMID:26831691

  14. Quantitative characterization of the surface topography of rolled sheets by laser scanning microscopy and fourier transformation

    NASA Astrophysics Data System (ADS)

    Gjønnes, Liv

    1996-08-01

    The surface of twin-roll cast aluminum sheets undergoes dramatic changes during cold rolling. This is mainly due to variables in the roll gap, topography of the rolls, lubrication, material properties, and in particular the initial structure and topography of the cast sheet. Therefore, it is important to have means to quantitatively describe the changes in the surface structure of each pass and from pass to pass in order to optimize the desired final surface structure. To achieve this, the laser scanning microscope (LSM) with its confocal technique has been employed to image the three-dimensional (3-D) topography and to digitize the image for further computer analysis. The digitization of the image is primarily motivated by the need to introduce a Fourier transformation of the surface topography. The method is effective in describing qualitative periodic trends in the surface features. Information is gained on the shape and periodicities as well as roughness directionality. For instance, grooves and cross hatches and their remnants can be followed from one pass to the other. Important characteristics of the surface topography such as rolling ridges and shingles can also easily be characterized.

  15. Characterization of primary human keratinocytes transformed by human papillomavirus type 18

    SciTech Connect

    Kaur, P.; McDougall, J.K. )

    1988-06-01

    Primary human epithelial cells were cotransfected with pHPV-18 and pSV2neo, and cell strains were generated by selecting in G418. Southern blot analysis revealed the presence of at least one intact, integrated viral genome in these cells. FE-A cells showed altered growth properties, characterized by a change in morphology, and clonal density. Differentiation markers analyzed by Western blotting (immunoblotting), such as cytokeratins and involucrin, indicated that the cells resembled a partially differentiated epithelial population. Increased expression of the 40-kilodalton cytokeratin was observed in FE-A cells, similar to that observed in simian virus 40-immortalized human keratinocytes. Calcium and 12-O-tetradecanoyl-phorbol-13-acetate treatment induced normal epithelial cells to differentiate, whereas the human papillomavirus 18 (HPV-18)-containing keratinocytes were resistant to these signals, indicating their partially transformed nature. These cells were not able to induce tumors in nude mice over a period of up to 8 months. A second cell strain, FE-H18L, also generated by transfecting HPV-18, also exhibited an extended life span and similar alterations in morphology. Viral RNA transcribed from the early region of HPV-18 was detected in both cell strains by Northern (RNA) blot analysis. These cell strains should provide a useful model for determining the role of HPV in carcinogenesis.

  16. Localized Gravity/Topography Correlation and Admittance Spectra one the Moon

    NASA Astrophysics Data System (ADS)

    Ishihara, Y.; Namiki, N.; Sugita, S.; Matsumoto, K.; Goossens, S.; Araki, H.; Noda, H.; Sasaki, S.; Iwata, T.; Hanada, H.

    2009-04-01

    Lunar surface and structure can be separate into two parts. The lunar near side crust and far side crust differ remarkably in thickness. This difference probably caused by difference of thermal evolution and state (elastic thickness) and catering history on both side. The correlations and admittance between the topography and gravity anomalies provide important information on the level of isostatic compensation of the lithosphere at the geological timescale, and reflect its thermo-mechanical state. Therefore, localized correlation and admittance analysis is one of the most important studies of selenodesy. A global correlation between topography and gravity of the Moon obtained by Clementine and Lunar Prospector missions, respectively, reveals high value at long wavelength and low value at short wavelength. Such characteristics are distinguished from those of the Earth and other terrestrial planets, whose global correlation between topography and gravity is low at long wavelength. The distinct correlation between topography and gravity of the Moon may indicate that the lunar topography is supported by multiple compensation mechanism. Further, an incomplete coverage of Doppler tracking data prior to Kaguya (SELENE) gravity experiment probably contributed to the correlation. Because the Moon is synchronously rotating with its revolution around the Earth, a spacecraft orbiting over the far side is not visible from ground stations. In either case, it is significant to decompose local correlation from global ones in order to investigate internal structure of the Moon from spherical harmonic model of gravity (LP75G [1]) and topography (GLTM-2 [2]). Japanese lunar exploration Kaguya (SELENE) has two kinds of selenodesical experiments. One is RSAT/VRAD (gravity mapping with direct tracking over far-side) experiment and another is Laser ALTimeter (LALT; topography mapping) experiment. These two experiments enable us to conduct localized analysis for the Moon. Therefore we

  17. Novel Thermographic Method for Characterizing Transformation Temperatures of Thin-Film Shape Memory Alloys Aimed at Combinatorial Approach

    NASA Astrophysics Data System (ADS)

    Aono, Yuko; Sakurai, Junpei; Shimokohbe, Akira; Hata, Seiichi

    2011-06-01

    A novel characterization method for the two-way martensitic transformation temperatures of thin-film shape memory alloys (SMAs) is proposed. The method uses thermography to detect the transformation as a change in emissivity. The proposed method was demonstrated for a Ti-Pd-Ni thin-film SMA along with electrical resistivity monitoring. Definite emissivity changes were observed during both heating and cooling. Furthermore, the changes in emissivity corresponded to changes in the electrical resistivity. To confirm the validity of the proposed method, the results were compared with results obtained using conventional differential scanning calorimetry (DSC). The reverse-martensitic transformation temperature was found to agree with the results of the proposed method. However, the martensitic transformation temperature did not agree well. The reason for this disagreement is the differences in the definition of the transformation temperature and stress conditions used. We expect that the proposed method will enable high-throughput characterization of SMAs by a combinatorial approach in the future.

  18. Characterization of oligodeoxynucleotides by electron detachment dissociation fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Yang, Jiong; Mo, Jingjie; Adamson, Julie T; Håkansson, Kristina

    2005-03-15

    Electron detachment dissociation (EDD), recently introduced by Zubarev and co-workers for the dissociation of multiply charged biomolecular anions via a radical ion intermediate, has been shown to be analogous to electron capture dissociation (ECD) in several respects, including more random peptide fragmentation and retention of labile posttranslational modifications. We have previously demonstrated unique fragmentation behavior in ECD compared to vibrational excitation for oligodeoxynucleotide cations. However, that approach is limited by the poor sensitivity for oligonucleotide ionization in positive ion mode. Here, we show implementation of EDD on a commercial Fourier transform ion cyclotron resonance mass spectrometer utilizing two different configurations: a heated filament electron source and an indirectly heated hollow dispenser cathode electron source. The dispenser cathode configuration provides higher EDD efficiency and additional fragmentation channels for hexamer oligodeoxynucleotides. As in ECD, even-electron d/w ion series dominate the spectra, but we also detect numerous a/z (both even-electron and radical species), (a/z - B), c/x, (c/x - B), and (d/w - B) ions with minimal nucleobase loss from the precursor ions. In contrast to previous high-energy collision-activated dissociation (CAD) and ion trap CAD of radical oligonucleotide anions, we only observe minimum sugar cross-ring cleavage, possibly due to the short time scale of EDD, which limits secondary fragmentation. Thus, EDD provides fragmentation similar to ECD for oligodeoxynucleotides but at enhanced sensitivity. Finally, we show that noncovalent bonding in a DNA duplex can be preserved following EDD, illustrating another analogy with ECD. We believe the latter finding implies EDD has promise for characterization of nucleic acid structure and folding. PMID:15762599

  19. Use of Admittance-Wall Models in Analysis of Radiating Line Antennas

    NASA Astrophysics Data System (ADS)

    Tammen, David John

    This thesis describes the development of analytical models for two radiating line antenna structures: the traveling -wave microstrip antenna and the Annular Sector Radiating Line (ANSERLIN) antenna. The models provide data and insights into the operation of the antennas without requiring large amounts of computation. It was shown that the general characteristics of the radiation patterns of ANSERLIN elements can be obtained using only a small number of circularly polarized spherical modes in the field expansion. A first -order model is obtained by solving for the fields of a closed waveguide with perfect electric conducting (PEC) top and bottom walls and perfect magnetic conducting (PMC) side walls. The propagation constant obtained from these fields of the closed waveguide is then used in the equivalent magnetic current filaments to obtain the radiated fields. Use of the propagation constant of the closed waveguide fields does not include the fringing and radiation behavior. A second-order model was developed in which the radiation loss and fringing fields are included by putting a small complex admittance on the side walls rather than having PMC side walls. Two formulations were developed to include the radiation loss in the representation: a coupled-mode formulation and an eigenvalue formulation. The coupled -mode formulation, which is similar to that described by Schelkunoff for a waveguide with lossy conductors, is used to obtain the complex-valued propagation constant. In the eigenvalue formulation, the eigenvalues obtained from the solution of the characteristic equation of the waveguide with admittance side walls are used to obtain the complex -valued propagation constant. This complex-valued propagation constant, which includes the fringing and radiation behavior, is then used in the equivalent magnetic current filaments to obtain the radiated fields. Good agreement was found between measured results and results computed using the eigenvalue formulation

  20. Morpho-anatomical characterization of mature embryo-derived callus of rice (Oryza sativa L.) suitable for transformation.

    PubMed

    Bevitori, R; Popielarska-Konieczna, M; dos Santos, E M; Grossi-de-Sá, M F; Petrofeza, S

    2014-05-01

    The objective of this study was to morpho-anatomically characterize embryogenic rice calli during early induction of somatic embryogenesis of three Brazilian rice cultivars. Herein, we explored embryogenic units (EUs) from 2-week-old cut proliferated calli to verify whether they were suitable for Agrobacterium tumefasciens-mediated transformation. Histological analysis and scanning electron microscopy (SEM) were used to analyze these types of calli during early rice callogenesis in the cultivars BRS Primavera, BRS Bonança, and BRS Caiapó. The characteristics of the embryogenic cells were preserved in the EUs, which showed a globular, compact structure that contained tightly packed cells and thus rendered the cells suitable for transformation. The EUs of BRS Caiapó also maintained the characteristics of the non-embryogenic callus, such as an elongated morphology and a lack of cellular organization. In general, the observations of the histological sections corresponded with those of the SEM images. The histological analysis suggested that all cultivars used in these experiments have morphogenic potential. The EUs from proliferated 2-week-old cut calli maintained their embryogenic features. The EUs were subjected to Agrobacterium-mediated transformation, which exhibited a regeneration frequency of 58 % for transformed hygromycin-resistant cell lines. These results show that EUs from proliferated 2-week-old cut calli are suitable for plant transformation. PMID:24085343

  1. An Admittance Survey of Large Volcanoes on Venus: Implications for Volcano Growth

    NASA Technical Reports Server (NTRS)

    Brian, A. W.; Smrekar, S. E.; Stofan, E. R.

    2004-01-01

    Estimates of the thickness of the venusian crust and elastic lithosphere are important in determining the rheological and thermal properties of Venus. These estimates offer insights into what conditions are needed for certain features, such as large volcanoes and coronae, to form. Lithospheric properties for much of the large volcano population on Venus are not well known. Previous studies of elastic thickness (Te) have concentrated on individual or small groups of edifices, or have used volcano models and fixed values of Te to match with observations of volcano morphologies. In addition, previous studies use different methods to estimate lithospheric parameters meaning it is difficult to compare their results. Following recent global studies of the admittance signatures exhibited by the venusian corona population, we performed a similar survey into large volcanoes in an effort to determine the range of lithospheric parameters shown by these features. This survey of the entire large volcano population used the same method throughout so that all estimates could be directly compared. By analysing a large number of edifices and comparing our results to observations of their morphology and models of volcano formation, we can help determine the controlling parameters that govern volcano growth on Venus.

  2. Admittance spectroscopy of solar cells based on GaPNAs layers

    SciTech Connect

    Baranov, A. I. Gudovskikh, A. S.; Zelentsov, K. S.; Nikitina, E. V.; Egorov, A. Yu.

    2015-04-15

    Admittance spectroscopy is used to study defect levels in the layers of a GaPNAs quaternary solid solution. Centers with an activation energy of 0.22 eV and a capture cross section of ∼2.4 × 10{sup −15} cm{sup 2} are found in doped n-GaPNAs layers grown on GaP substrates. These centers correspond to already known Si{sub Ga} + V{sub P} defects in n-GaP; annealing decreases their concentration by several times. A level with an activation energy of 0.23–0.24 eV and capture cross section of ∼9.0 × 10{sup −20} cm{sup 2} is found in undoped GaPNAs layers grown on Si and GaP substrates. The concentration of these centers substantially decreases upon annealing, and, at annealing temperatures exceeding 600°C, there is absolutely no response from these defects. For undoped GaPNAs layers grown on GaP substrates, a level with an activation energy of 0.18 eV and capture cross section of ∼1.1 × 10{sup −16} cm{sup 2} is also found. The concentration of these centers remains unchanged upon annealing.

  3. Inconsistent Definitions of the Pressure-Coupled Response and the Admittance of Solid Propellants

    NASA Technical Reports Server (NTRS)

    Cardiff, Eric H.

    2003-01-01

    When an acoustic wave is present in a solid propellant combustion environment, the mass flux from the combustion zone oscillates at the same frequency as the acoustics. The acoustic wave is either amplified or attenuated by the response of the combustion to the acoustic disturbance. When the acoustic wave is amplified, this process is called combustion instability. The amplification is quantitatively measured by a response function. The ability to predict combustion stability for a solid propellant formulation is essential to the formulator to prevent or minimize the effects of instabilities, such as an oscillatory thrust. Unfortunately, the prediction of response values for a particular propellant remains a technical challenge. Most predictions of the response of propellants are based on test data, but there are a number of questions about the reliability of the standard test method, the T-burner. Alternate methods have been developed to measure the response of a propellant, including the ultrasound burner, the magnetic flowmeter and the rotating valve burner, but there are still inconsistencies between the results obtained by these different methods. Aside from the experimental differences, the values of the pressure-coupled responses obtained by different researchers are often compared erroneously, for the simple reason that inconsistencies in the definitions of the responses and admittances are not considered. The use of different definitions has led to substantial confusion since the first theoretical treatments of the problem by Hart and McClure in 1959. The definitions and relations derived here seek to alleviate this problem.

  4. Universal Impedance, Admittance and Scattering Fluctuations in Quantum-chaotic Systems

    NASA Astrophysics Data System (ADS)

    Hemmady, Sameer

    2006-03-01

    We experimentally investigate fluctuations in the eigenvalues of the impedance, admittance and scattering matrices of wave chaotic systems using a microwave analog of a quantum chaotic infinite square well potential. We consider a 2-D, time-reversal symmetric chaotic microwave resonator driven by two non-ideally coupled ports. The system-specific coupling effects are removed using the measured radiation impedance matrix (3pt<->Z Rad) [1] of the two ports. A normalized impedance matrix (3pt<->z ) is thus obtained, and the Probability Density Function (PDF) of its eigenvalues is predicted to be universal depending only on the cavity loss. We observe remarkable agreement between the statistical properties of 3pt<->z and 3pt<->y =3pt<->z -1 for all degrees of loss, which is in accordance with [1, 2] and Random Matrix Theory (RMT). We compare the joint PDF of the eigenphases of the normalized scattering matrix (3pt<->s ) with that obtained from RMT for varying degrees of loss. We study the joint PDF of the eigenvalues of 3pt<->s 3pt<->s ^ and find good agreement with [3]. [1] X. Zheng, et al., -- Electromagnetics (in press); condmat/0408317; S. Hemmady, et al., Phys. Rev. Lett. 94, 014102 (2005).[2] Y. V. Fyodorov, et al.,-- condmat/0507016.[3] P. W. Brouwer and C. W. J Beenakker -- PRB 55, 4695 (1997). Work supported by DOD MURI AFOSR Grant F496200110374, DURIP Grants FA95500410295 and FA95500510240.

  5. Universal Impedance, Admittance and Scattering Fluctuations in Quantum-chaotic Systems.

    NASA Astrophysics Data System (ADS)

    Hemmady, Sameer; Zheng, Xing; Antonsen, Thomas; Ott, Edward; Anlage, Steven M.

    2006-03-01

    We experimentally investigate fluctuations in the eigenvalues of the impedance, admittance and scattering matrices of wave chaotic systems using a microwave analog of a quantum chaotic infinite square well potential. We consider a 2-D, time-reversal symmetric chaotic microwave resonator driven by two non-ideally coupled ports. The system-specific coupling effects are removed using the measured radiation impedance matrix (3pt<->Z Rad) [1] of the two ports. A normalized impedance matrix (3pt<->z ) is thus obtained, and the Probability Density Function (PDF) of its eigenvalues is predicted to be universal depending only on the cavity loss. We observe remarkable agreement between the statistical properties of 3pt<->z and 3pt<->y =3pt<->z -1 for all degrees of loss, which is in accordance with [1, 2] and Random Matrix Theory (RMT). We compare the joint PDF of the eigenphases of the normalized scattering matrix (3pt<->s ) with that obtained from RMT for varying degrees of loss. We study the joint PDF of the eigenvalues of 3pt<->s 3pt<->s ^ and find good agreement with [3]. [1] X. Zheng, et al., -- Electromagnetics (in press); condmat/0408317; S. Hemmady, et al., Phys. Rev. Lett. 94, 014102 (2005).[2] Y. V. Fyodorov, et al.,-- condmat/0507016.[3] P. W. Brouwer and C. W. J Beenakker -- PRB 55, 4695 (1997). Work supported by DOD MURI AFOSR Grant F496200110374, DURIP Grants FA95500410295 and FA95500510240.

  6. Characterizing the microstructures of biological tissues using Mueller matrix and transformed polarization parameters

    PubMed Central

    Sun, Minghao; He, Honghui; Zeng, Nan; Du, E; Guo, Yihong; Liu, Shaoxiong; Wu, Jian; He, Yonghong; Ma, Hui

    2014-01-01

    Mueller matrices can be used as a powerful tool to probe qualitatively the microstructures of biological tissues. Certain transformation processes can provide new sets of parameters which are functions of the Mueller matrix elements but represent more explicitly the characteristic features of the sample. In this paper, we take the backscattering Mueller matrices of a group of tissues with distinctive structural properties. Using both experiments and Monte Carlo simulations, we demonstrate qualitatively the characteristic features of Mueller matrices corresponding to different structural and optical properties. We also calculate two sets of transformed polarization parameters using the Mueller matrix transformation (MMT) and Mueller matrix polar decomposition (MMPD) techniques. We demonstrate that the new parameters can separate the effects due to sample orientation and present quantitatively certain characteristic features of these tissues. Finally, we apply the transformed polarization parameters to the unstained human cervix cancerous tissues. Preliminary results show that the transformed polarization parameters can provide characteristic information to distinguish the cancerous and healthy tissues. PMID:25574434

  7. Electromagnetic characterization of current transformer with toroidal core under sinusoidal conditions

    NASA Astrophysics Data System (ADS)

    Koprivica, Branko; Milovanovic, Alenka

    2016-04-01

    The aim of this paper is to present a new procedure for the electromagnetic analysis of a measuring current transformer under sinusoidal conditions in its electrical and magnetic circuit. The influence of the magnetic hysteresis has been taken into account using the measured inverse magnetization curve and phase lag between the time waveforms of the magnetic field and the magnetic induction. Using the proposed analysis, ratio and phase errors of the current transformer have been calculated. The results of the calculation have been compared with experimental results and a good agreement has been found.

  8. Establishment and characterization of hamster cell lines transformed by restriction endonuclease fragments of adenovirus 5.

    PubMed Central

    Rowe, D T; Branton, P E; Yee, S P; Bacchetti, S; Graham, F L

    1984-01-01

    We have established a library of hamster cells transformed by adenovirus 5 DNA fragments comprising all (XhoI-C, 0 to 16 map units) or only a part (HindIII-G, 0 to 7.8 map units) of early region 1 (E1: 0 to 11.2 map units). These lines have been analyzed in terms of content of viral DNA, expression of E1 antigens, and capacity to induce tumors in hamsters. All cells tested were found to express up to eight proteins encoded within E1A (0 to 4.5 map units) with apparent molecular weights between 52,000 (52K) and 25K. Both G and C fragment-transformed lines expressed a 19K antigen encoded within E1B (4.5 to 11.2 map units), whereas an E1B 58K protein was detected in C fragment-transformed, but not G-fragment-transformed, lines. No clear distinction could be drawn between cells transformed by HindIII-G and by XhoI-C in terms of morphology or tumorigenicity, suggesting that the E1B 58K antigen plays no major role in the maintenance of oncogenic transformation, although possible involvement of truncated forms of 58K cannot be ruled out. Sera were collected from tumor-bearing animals and examined for ability to immunoprecipitate proteins from infected cells. The relative avidity of sera for different proteins was characteristic of the cell line used for tumor induction, and the specificity generally reflected the array of viral proteins expressed by the corresponding transformed cells. However, one notable observation was that even though all transformed lines examined expressed antigens encoded by both the 1.1- and 0.9-kilobase mRNAs transcribed from E1A, tumor sera made against these lines only precipitated products of the 1.1-kilobase message. Thus, two families of E1A proteins, highly related in terms of primary amino acid sequence, appear to be immunologically quite distinct. Images PMID:6690708

  9. Agronomic performance and genetic characterization of sugarcane transformed for resistance to sugarcane yellow leaf virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Sugar Cane Yellow Leaf Virus (SCYLV) is widespread in Florida, and SCYLV resistance in the Canal Point (CP) sugarcane population is limited. The objectives of this study were to 1) evaluate the agronomic performance of two transgenic lines transformed for SCYLV resistance (6-1, 6-2) compared to ...

  10. An analysis of light-induced admittance changes in rod outer segments

    PubMed Central

    Falk, G.; Fatt, P.

    1973-01-01

    1. Measurements were made of the time course and amplitude of the change in real part of admittance, ΔG, of a suspension of frog rod outer segments, following a flash of light bleaching about 1% of the rhodopsin content of the rods. The measurements, based on the use of a specially designed marginal oscillator, covered the frequency range between 500 Hz and 17 MHz. 2. The components of response, previously described for rods prepared by a method involving exposure to strongly hypertonic sucrose solutions, are present in similar form when rods are isolated and maintained in isotonic solutions made up with equi-osmotic concentrations of NaCl and sucrose or with Na2SO4. 3. Component I, identified as a slowly developing positive ΔG apparent at very low frequencies, is frequency-independent up to the characteristic frequency of admittance for the suspension, fY (about 2 MHz for rods suspended in a solution having the conductivity of Ringer solution), but decreases at still higher frequencies. 4. Component II, identified as a rapidly developing positive ΔG which appears only above a critical frequency about 2·5 decades below fY, increases approximately logarithmically with frequency to reach a limiting amplitude in the region of fY. 5. The amplitude of component II, ΔGII, measured in the region of fY, varies linearly with the conductivity of the suspending medium, Go, under conditions in which the conductivity of the rod interior is also a linear function of the external conductivity. The relation for a flash bleaching 1% of the rhodopsin content of the dark-adapted rod is [Formula: see text] 6. Measurements made on rods suspended in a low-conductivity solution, which has the effect of reducing the conductivity of the rod interior to about one ninth its value for rods suspended in Ringer solution, reveal a decline in component II for frequencies above 8 MHz. 7. To explain the frequency dependence of component II and its dependence on conductivity, it is proposed

  11. Characterization of pyrogenic black carbon by desorption atmospheric pressure photoionization Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Podgorski, David C; Hamdan, Rasha; McKenna, Amy M; Nyadong, Leonard; Rodgers, Ryan P; Marshall, Alan G; Cooper, William T

    2012-02-01

    We present a new method for molecular characterization of intact biochar directly, without sample preparation or pretreatment, on the basis of desorption atmospheric pressure photoionization (DAPPI) coupled to Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. Conventional ionization methods (e.g., electrospray or atmospheric pressure photoionization) for characterization of natural organic matter have limited utility for the characterization of chars due to incomplete solubility in common solvents. Therefore, direct ionization techniques that do not require sample dissolution prior to analysis are ideal. Here, we apply DAPPI FTICR mass spectrometry to enable the first molecular characterization of uncharred parent oak biomass and after combustion (250 °C) or pyrolysis (400 °C). Parent oak is primarily composed of cellulose-, lignin-, and resin-like compounds. Oak combusted at 250 °C contains condensed aromatic compounds with low H/C and O/C ratios while retaining compounds with high H/C and O/C ratios. The bimodal distribution of aromatic and aliphatic compounds observed in the combusted oak sample is attributed to incomplete thermal degradation of lignin and hemicellulose. Pyrolyzed oak constituents exhibit lower H/C and O/C ratios: approximately three-quarters of the identified species are aromatic. DAPPI FTICR MS results agree with bulk elemental composition as well as functional group distributions determined by elemental analysis and solid state (13)C NMR spectroscopy. Complete molecular characterization of biomass upon thermal transformation may provide insight into the biogeochemical cycles of biochar and future renewable energy sources, particularly for samples currently limited by solubility, separation, and sample preparation. PMID:22242739

  12. Speech signal denoising with wavelet-transforms and the mean opinion score characterizing the filtering quality

    NASA Astrophysics Data System (ADS)

    Yaseen, Alauldeen S.; Pavlov, Alexey N.; Hramov, Alexander E.

    2016-03-01

    Speech signal processing is widely used to reduce noise impact in acquired data. During the last decades, wavelet-based filtering techniques are often applied in communication systems due to their advantages in signal denoising as compared with Fourier-based methods. In this study we consider applications of a 1-D double density complex wavelet transform (1D-DDCWT) and compare the results with the standard 1-D discrete wavelet-transform (1DDWT). The performances of the considered techniques are compared using the mean opinion score (MOS) being the primary metric for the quality of the processed signals. A two-dimensional extension of this approach can be used for effective image denoising.

  13. Lime kiln source characterization: Lime manufacturing industry Fourier transform infrared spectroscopy. Final report

    SciTech Connect

    Toney, M.L.

    1999-07-01

    The purpose of this testing program is to obtain uncontrolled and controlled hydrogen chloride (HCl) and speciated hydrocarbon Hazardous Air Pollutants (HAPs) emissions data from lime production plants to support a national emission standard for hazardous air pollutants (NESHAP). This report presents data from the Fourier Transform Infrared Spectroscopy (FTIR) measurements. FTIR source testing was conducted for the following purposes: Quantify HCl emission levels; and Gather screening (i.e., qualitative) data on other HAP emissions.

  14. Microbial toxicity and characterization of DNAN (bio)transformation product mixtures.

    PubMed

    Olivares, Christopher I; Sierra-Alvarez, Reyes; Alvarez-Nieto, Cristina; Abrell, Leif; Chorover, Jon; Field, Jim A

    2016-07-01

    2,4-Dinitroanisole (DNAN) is an emerging insensitive munitions compound. It undergoes rapid (bio)transformation in soils and anaerobic sludge. The primary transformation pathway catalyzed by a combination of biotic and abiotic factors is nitrogroup reduction followed by coupling of reactive intermediates to form azo-dimers. Additional pathways include N-acetylation and O-demethoxylation. Toxicity due to (bio)transformation products of DNAN has received little attention. In this study, the toxicity of DNAN (bio)transformation monomer products and azo-dimer and trimer surrogates to acetoclastic methanogens and the marine bioluminescent bacterium, Allivibrio fischeri, were evaluated. Methanogens were severely inhibited by 3-nitro-4-methoxyaniline (MENA), with a 50%-inhibiting concentration (IC50) of 25 μM, which is more toxic than DNAN with the same assay, but posed a lower toxicity to Allivibrio fischeri (IC50 = 219 μM). On the other hand, N-(5-amino-2-methoxyphenyl) acetamide (Ac-DAAN) was the least inhibitory test-compound for both microbial targets. Azo-dimer and trimer surrogates were very highly toxic to both microbial systems, with a toxicity similar or stronger than that of DNAN. A semi-quantitative LC-QTOF-MS method was employed to determine product mixture profiles at different stages of biotransformation, and compared with the microbial toxicity of the product-mixtures formed. Methanogenic toxicity increased due to putative reactive nitroso-intermediates as DNAN was reduced. However, the inhibition later attenuated as dimers became the predominant products in the mixtures. In contrast, A. fischeri tolerated the initial biotransformation products but were highly inhibited by the predominant azo-dimer products formed at longer incubation times, suggesting these ultimate products are more toxic than DNAN. PMID:27085064

  15. Characterizing the Moisture Content of Tea with Diffuse Reflectance Spectroscopy Using Wavelet Transform and Multivariate Analysis

    PubMed Central

    Li, Xiaoli; Xie, Chuanqi; He, Yong; Qiu, Zhengjun; Zhang, Yanchao

    2012-01-01

    Effects of the moisture content (MC) of tea on diffuse reflectance spectroscopy were investigated by integrated wavelet transform and multivariate analysis. A total of 738 representative samples, including fresh tea leaves, manufactured tea and partially processed tea were collected for spectral measurement in the 325–1,075 nm range with a field portable spectroradiometer. Then wavelet transform (WT) and multivariate analysis were adopted for quantitative determination of the relationship between MC and spectral data. Three feature extraction methods including WT, principal component analysis (PCA) and kernel principal component analysis (KPCA) were used to explore the internal structure of spectral data. Comparison of those three methods indicated that the variables generated by WT could efficiently discover structural information of spectral data. Calibration involving seeking the relationship between MC and spectral data was executed by using regression analysis, including partial least squares regression, multiple linear regression and least square support vector machine. Results showed that there was a significant correlation between MC and spectral data (r = 0.991, RMSEP = 0.034). Moreover, the effective wavelengths for MC measurement were detected at range of 888–1,007 nm by wavelet transform. The results indicated that the diffuse reflectance spectroscopy of tea is highly correlated with MC. PMID:23012574

  16. Isolation and characterization of membranes from normal and transformed tissue-culture cells

    PubMed Central

    Graham, John M.

    1972-01-01

    Homogenates of baby-hamster kidney cells and rat embryo fibroblasts prepared by nitrogen cavitation contain a small population of slowly sedimenting mitochondria or mitochondrial fragments, which contaminate the microsomal fraction. This appears to limit the resolution of surface membrane and endoplasmic reticulum on magnesium-containing dextran gradients. The microsomal material and mitochondria can, however, be completely separated on a 10–60% (w/w) sucrose zonal gradient containing a 30% sucrose plateau. On magnesium-containing dextran gradients this mitochondria-free microsomal material can be resolved into at least two surface membrane fractions and at least two endoplasmic reticulum fractions. Comparison of polyoma virus-transformed and normal baby-hamster kidney cells reveals some interesting differences in their microsomal fractionation patterns and the characteristics of the Na+/K+-Mg2+ adenosine triphosphatase of their surface membranes, in particular a tenfold lower Km in the virus-transformed cells. The fractionation patterns of normal and spontaneously transformed rat embryo fibroblasts are also briefly discussed, particularly in relation to the significance of the observation that both the surface membrane and endoplasmic reticulum from these cells can be subfractionated. PMID:4348259

  17. Transformation of Chloroplast Ribosomal RNA Genes in Chlamydomonas: Molecular and Genetic Characterization of Integration Events

    PubMed Central

    Newman, S. M.; Boynton, J. E.; Gillham, N. W.; Randolph-Anderson, B. L.; Johnson, A. M.; Harris, E. H.

    1990-01-01

    Transformation of chloroplast ribosomal RNA (rRNA) genes in Chlamydomonas has been achieved by the biolistic process using cloned chloroplast DNA fragments carrying mutations that confer antibiotic resistance. The sites of exchange employed during the integration of the donor DNA into the recipient genome have been localized using a combination of antibiotic resistance mutations in the 16S and 23S rRNA genes and restriction fragment length polymorphisms that flank these genes. Complete or nearly complete replacement of a region of the chloroplast genome in the recipient cell by the corresponding sequence from the donor plasmid was the most common integration event. Exchange events between the homologous donor and recipient sequences occurred preferentially near the vector:insert junctions. Insertion of the donor rRNA genes and flanking sequences into one inverted repeat of the recipient genome was followed by intramolecular copy correction so that both copies of the inverted repeat acquired identical sequences. Increased frequencies of rRNA gene transformants were achieved by reducing the copy number of the chloroplast genome in the recipient cells and by decreasing the heterology between donor and recipient DNA sequences flanking the selectable markers. In addition to producing bona fide chloroplast rRNA transformants, the biolistic process induced mutants resistant to low levels of streptomycin, typical of nuclear mutations in Chlamydomonas. PMID:1981764

  18. An Investigation into the Admittance of MIS-Structures Based on MBE HgCdTe with Quantum Wells

    NASA Astrophysics Data System (ADS)

    Dzyadukh, S. M.; Voitsekhovskii, A. V.; Nesmelov, S. N.; Dvoretskii, S. A.; N. Mikhailov, N.; Gorn, D. I.

    2013-12-01

    The results of investigations into the complex admittance of the MIS-structures based on heteroepitaxial MBE Hg1- x Cd x Te with quantum wells (QW) in the test-signal frequency range 1 kHz - 2 МHz at temperatures 8-300 K are reported. The thickness of single HgTe QWs was 5.6 and 7.1 nm, the content in the 35-nm thick barrier layers - 0.65 and 0.62, respectively.

  19. Clinicopathologic and Immunophenotypic Characterization of 25 Cases of Acinic Cell Carcinoma with High-Grade Transformation.

    PubMed

    Thompson, Lester D; Aslam, Muhammad N; Stall, Jennifer N; Udager, Aaron M; Chiosea, Simion; McHugh, Jonathan B

    2016-06-01

    Acinic cell carcinoma (AiCC) with high-grade transformation is a rare variant of AiCC composed of both a conventional low-grade (LG) AiCC and a separate high-grade (HG) component. We describe here, the clinicopathologic and immunohistochemical features of 25 cases diagnosed between 1990 and 2015. Available tissue was analyzed and compared with a cohort of pure LG AiCC for the morphologic and immunophenotypic profile. Incidence was higher in females (1.8:1) than males with an overall mean age at presentation of 63.2 years. All tumors occurred in the parotid gland including 76 % with facial nerve trunk and branches involvement. Most patients were treated with extensive resection and adjuvant therapy. Local recurrence or distant metastasis occurred in most patients, with 72.7 % dead with disease (mean 2.9 years) and 3 patients alive with disease (mean 2.4 years). The majority of the tumors were composed of a LG microcystic AiCC and a HG component consisting of invasive lobules of undifferentiated cells with predominantly solid, cribriform, and glandular patterns. Acinic differentiation was still present in HG areas but aggressive features such as perineural invasion (76 %), lymphovascular invasion (62 %), positive margins (72 %), high mitotic rate, atypical mitoses and/or comedonecrosis (86 %) were easily identified. Compared to the pure LG AiCC, the cases with HG transformation showed significantly increased expression of cyclin-D1, p53 and Ki-67. Most HG areas of AiCC expressed membranous β-catenin (92 %) and were negative for p63 (three cases were focally positive), S100, SMA, androgen, and estrogen receptors. DOG1 expression was present in all LG AiCC tested with retained expression in 91 % of cases with HG transformation, supporting acinic differentiation in the HG foci. Recognition of AiCC with high-grade transformation is imperative as more aggressive clinical management is warranted. PMID:26245749

  20. Characterization of directly transformed weedy Brassica rapa and introgressed B. rapa with Bt cry1Ac and gfp genes.

    PubMed

    Moon, Hong S; Halfhill, Matthew D; Good, Laura L; Raymer, Paul L; Neal Stewart, C

    2007-07-01

    Crop to weed transgene flow, which could result in more competitive weed populations, is an agricultural biosafety concern. Crop Brassica napus to weedy Brassica rapa hybridization has been extensively characterized to better understand the transgene flow and its consequences. In this study, weedy accessions of B. rapa were transformed with Bacillus thuringiensis (Bt) cry1Ac- and green fluorescence protein (gfp)-coding transgenes using Agrobacterium to assess ecological performance of the wild biotype relative to introgressed hybrids in which the transgenic parent was the crop. Regenerated transgenic B. rapa events were characterized by progeny analysis, Bt protein enzyme-linked immunosorbent assay (ELISA), Southern blot analysis, and GFP expression assay. GFP expression level and Bt protein concentration were significantly different between independent transgenic B. rapa events. Similar reproductive productivity was observed in comparison between transgenic B. rapa events and B. rapa x B. napus introgressed hybrids in greenhouse and field experiments. In the greenhouse, Bt transgenic plants experienced significantly less herbivory damage from the diamondback moth (Plutella xylostella). No differences were found in the field experiment under ambient, low, herbivore pressure. Directly transformed transgenic B. rapa plants should be a helpful experimental control to better understand crop genetic load in introgressed transgenic weeds. PMID:17333014

  1. Biochemical and molecular characterization of Coriolopsis rigida laccases involved in transformation of the solid waste from olive oil production.

    PubMed

    Díaz, Rosario; Saparrat, Mario C N; Jurado, Miguel; García-Romera, Inmaculada; Ocampo, Juan Antonio; Martínez, María Jesús

    2010-09-01

    Two laccase isoenzymes were purified and characterized from the basidiomycete Coriolopsis rigida during transformation of the water-soluble fraction of "alpeorujo" (WSFA), a solid residue derived from the olive oil production containing high levels of toxic compounds. Zymogram assays of laccases secreted by the fungus growing on WSFA and WSFA supplemented with glucose showed two bands with isoelectric points of 3.3 and 3.4. The kinetic studies of the two purified isoenzymes showed similar affinity on 2,6-dimethoxyphenol and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid), used as phenolic and non-phenolic model substrate, respectively. The molecular mass of both proteins was 66 kDa with 9% N-linked carbohydrate. Physico-chemical properties of the purified laccases from media containing WSFA were similar to those obtained from medium with glucose as the main carbon source. In-vitro studies performed with the purified laccases revealed a 42% phenol reduction of WSFA, as well as changes in the molecular mass distribution. These findings indicate that these laccases are involved in the process of transformation, via polymerization by the oxidation of phenolic compounds present in WSFA. A single laccase gene, containing an open reading frame of 1,488 bp, was obtained in PCR amplifications performed with cDNA extracted from mycelia grown on WSFA. The product of the gene shares 90% identity (95% similarity) with a laccase from Trametes trogii and 89% identity (95% similarity) with a laccase from Coriolopsis gallica. This is the first report on purification and molecular characterization of laccases directly involved in the transformation of olive oil residues. PMID:20607234

  2. Processing and characterization of transformation-toughened ceramics with strength retention to elevated temperatures. Final report

    SciTech Connect

    Cutler, R.A.; Brinkpeter, C.B.; Vircar, A.V.; Shetty, D.K.

    1994-09-01

    Monolithic and three-layered Al{sub 2}O{sub 3} -- 15 vol % ZrO{sub 2} composites were fabricated by slip casting aqueous slurries. The outer and inner layers of three-layer composites contained unstabilized and partially stabilized ZrO{sub 2}, respectively. Transformation of part of the unstabilized ZrO{sub 2} led to surface compressive stresses in the outer layers. Strain gage, x-ray, indentation crack length, and strength measurements were used to determine the magnitude of residual stresses in the composites. The strength of the three-layer composites ({approx}1200 MPa) was 500--700 MPa higher than that of the monolithic outer layer composites at room temperature and 350 MPa higher at 750{degree}C. The strength differential decreased rapidly above the m {yields} t transformation temperature. Three-layered composites showed excellent damage resistance and improved reliability. Cam follower rollers were fabricated to demonstrate the applicability of this technique for making automotive components.

  3. In-situ characterization of highly reversible phase transformation by synchrotron X-ray Laue microdiffraction

    NASA Astrophysics Data System (ADS)

    Chen, Xian; Tamura, Nobumichi; MacDowell, Alastair; James, Richard D.

    2016-05-01

    The alloy Cu25Au30Zn45 undergoes a huge first-order phase transformation (6% strain) and shows a high reversibility under thermal cycling and an unusual martensitc microstructure in sharp contrast to its nearby compositions. This alloy was discovered by systematically tuning the composition so that its lattice parameters satisfy the cofactor conditions (i.e., the kinematic conditions of compatibility between phases). It was conjectured that satisfaction of these conditions is responsible for the enhanced reversibility as well as the observed unusual fluid-like microstructure during transformation, but so far, there has been no direct evidence confirming that these observed microstructures are those predicted by the cofactor conditions. To verify this hypothesis, we use synchrotron X-ray Laue microdiffraction to measure the orientations and structural parameters of variants and phases near the austenite/martensite interface. The areas consisting of both austenite and multi-variants of martensite are scanned by microLaue diffraction. The cofactor conditions have been examined from the kinematic relation of lattice vectors across the interface. The continuity condition of the interface is precisely verified from the correspondent lattice vectors between two phases.

  4. Computational Modeling and Experimental Characterization of Martensitic Transformations in Nicoal for Self-Sensing Materials

    NASA Technical Reports Server (NTRS)

    Wallace, T. A.; Yamakov, V. I.; Hochhalter, J. D.; Leser, W. P.; Warner, J. E.; Newman, J. A.; Purja Pun, G. P.; Mishin, Y.

    2015-01-01

    Fundamental changes to aero-vehicle management require the utilization of automated health monitoring of vehicle structural components. A novel method is the use of self-sensing materials, which contain embedded sensory particles (SP). SPs are micron-sized pieces of shape-memory alloy that undergo transformation when the local strain reaches a prescribed threshold. The transformation is a result of a spontaneous rearrangement of the atoms in the crystal lattice under intensified stress near damaged locations, generating acoustic waves of a specific spectrum that can be detected by a suitably placed sensor. The sensitivity of the method depends on the strength of the emitted signal and its propagation through the material. To study the transition behavior of the sensory particle inside a metal matrix under load, a simulation approach based on a coupled atomistic-continuum model is used. The simulation results indicate a strong dependence of the particle's pseudoelastic response on its crystallographic orientation with respect to the loading direction and suggest possible ways of optimizing particle sensitivity. The technology of embedded sensory particles will serve as the key element in an autonomous structural health monitoring system that will constantly monitor for damage initiation in service, which will enable quick detection of unforeseen damage initiation in real-time and during onground inspections.

  5. TEM characterization of planar defects in massively transformed TiAl alloy

    SciTech Connect

    Zhang, X.D.; Wiezorek, J.M.K.; Fraser, H.L.; Kaufman, M.J.; Loretto, M.H.

    1997-12-31

    The microstructure of a massively transformed Ti-49at.%Al alloy has been studied by conventional transmission electron microscopy (CTEM) and high resolution TEM (HREM). A high density of planar defects, namely complex anti-phase domain boundaries (CAPDB) and thermal micro-twins (TMT) have been observed. CTEM images and diffraction patterns showed that two anti-phase related {gamma}-matrix domains were generally separated by a thin layer of a 90{degree}-domain, for which the c-axis is rotated 90{degree} over a common cube axis with respect to those of the {gamma}-matrix domains. HREM confirmed the presence of two crystallographically different types of 90{degree}-domains being associated with the CAPDB. Furthermore, interactions between the CAPDB and TMT have been observed. Local faceting of the generally wavy, non-crystallographic CAPDB parallel to the {l_brace}111{r_brace}-twinning planes occurred due to interaction with the TMT. The relaxation of the CAPDB onto {l_brace}111{r_brace} required diffusion which is proposed to be enhanced locally in the presence of the dislocations associated with the formation of TMT during the massive transformation.

  6. Characterization of carbon ion implantation induced graded microstructure and phase transformation in stainless steel

    SciTech Connect

    Feng, Kai; Wang, Yibo; Li, Zhuguo; Chu, Paul K.

    2015-08-15

    Austenitic stainless steel 316L is ion implanted by carbon with implantation fluences of 1.2 × 10{sup 17} ions-cm{sup −} {sup 2}, 2.4 × 10{sup 17} ions-cm{sup −} {sup 2}, and 4.8 × 10{sup 17} ions-cm{sup −} {sup 2}. The ion implantation induced graded microstructure and phase transformation in stainless steel is investigated by X-ray diffraction, X-ray photoelectron spectroscopy and high resolution transmission electron microscopy. The corrosion resistance is evaluated by potentiodynamic test. It is found that the initial phase is austenite with a small amount of ferrite. After low fluence carbon ion implantation, an amorphous layer and ferrite phase enriched region underneath are formed. Nanophase particles precipitate from the amorphous layer due to energy minimization and irradiation at larger ion implantation fluence. The morphology of the precipitated nanophase particles changes from circular to dumbbell-like with increasing implantation fluence. The corrosion resistance of stainless steel is enhanced by the formation of amorphous layer and graphitic solid state carbon after carbon ion implantation. - Highlights: • Carbon implantation leads to phase transformation from austenite to ferrite. • The passive film on SS316L becomes thinner after carbon ion implantation. • An amorphous layer is formed by carbon ion implantation. • Nanophase precipitate from amorphous layer at higher ion implantation fluence. • Corrosion resistance of SS316L is improved by carbon implantation.

  7. Characterization of Streptomyces sp. strain DRS-1 and its ampicillin transformation product.

    PubMed

    Roy, D; Sharma, A; Bhowmick, G; Roy, M K; Ghosh, A C

    1997-01-01

    Incubation of ampicillin with whole cells of Streptomyces sp. DRS-1 resulted in accumulation of four compounds different from ampicillin. One of them was isolated, purified and partially characterized. On the basis of spectroscopic characteristics, RF value and antibacterial activity the compound was identified as cephalexin. It could also be obtained from ampicillin by using crude protein extract of the strain. PMID:9527516

  8. Establishment and characterization of a simian virus 40-transformed temperature-sensitive rat luteal cell line.

    PubMed

    Sugino, N; Zilberstein, M; Srivastava, R K; Telleria, C M; Nelson, S E; Risk, M; Chou, J Y; Gibori, G

    1998-04-01

    The primary culture of rat luteal cells and their long-term maintenance have been difficult. Low cellular yields have limited the possibility for the study of gene regulation in luteal cells. The goal of this study was to develop a cell line to serve as a model by which to study the expression and regulation of various genes specific to luteal cells. We attempted to develop a luteal cell line by transformation of large luteal cells through infection with a temperature-sensitive simian virus (SV-40 tsA209) mutant that has a temperature-sensitive mutation required for the maintenance of cell transformation. We report here the successful establishment of such a cell line, designated GG-CL cells. Large luteal cells were purified to homogeneity by flow cytometry from corpora lutea of day 14 pregnant rats, cultured for 24 h, and then infected with the SV-40 tsA209 mutant virus. Transformed cells were maintained at the permissive temperature (33 C) until colonies were identified. Several colonies of transformed cells were isolated and passaged. They multiplied at 33 C and formed multilayers. At the nonpermissive temperature (40 C), cells reverted to the normal differentiated phenotype similar to the primary luteal cells in culture. To determine whether GG-CL cells express the genes found in normal luteal cells, messenger RNA (mRNA) expression was examined by either Northern analysis or RT-PCR with primers specific to each mRNA. GG-CL cells were found to express receptors for interleukin-6 and glucocorticoid, as well as the newly discovered estrogen receptor-beta (ER-beta) and the orphan nuclear receptor nur 77. No receptors for ER-alpha, progesterone, LH, or PRL could be detected. This cell line also expressed 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD), but not cholesterol side-chain cleavage cytochrome P450 (P450scc), 3beta-hydroxysteroid dehydrogenase, or aromatase cytochrome P450 (P450arom). Although the cells did not express the PRL receptor, they did express

  9. Force Control and Nonlinear Master-Slave Force Profile to Manage an Admittance Type Multi-Fingered Haptic User Interface

    SciTech Connect

    Anthony L. Crawford

    2012-08-01

    Natural movements and force feedback are important elements in using teleoperated equipment if complex and speedy manipulation tasks are to be accomplished in remote and/or hazardous environments, such as hot cells, glove boxes, decommissioning, explosives disarmament, and space to name a few. In order to achieve this end the research presented in this paper has developed an admittance type exoskeleton like multi-fingered haptic hand user interface that secures the user’s palm and provides 3-dimensional force feedback to the user’s fingertips. Atypical to conventional haptic hand user interfaces that limit themselves to integrating the human hand’s characteristics just into the system’s mechanical design this system also perpetuates that inspiration into the designed user interface’s controller. This is achieved by manifesting the property differences of manipulation and grasping activities as they pertain to the human hand into a nonlinear master-slave force relationship. The results presented in this paper show that the admittance-type system has sufficient bandwidth that it appears nearly transparent to the user when the user is in free motion and when the system is subjected to a manipulation task, increased performance is achieved using the nonlinear force relationship compared to the traditional linear scaling techniques implemented in the vast majority of systems.

  10. Direct chemical characterization of natural wood resins by temperature-resolved and space-resolved Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Jian-bo; Zhou, Qun; Sun, Su-qin

    2016-07-01

    Wood resins are valuable natural products with wide utilizations. Either in the form of resin exudates or in the form of resin-containing woods, natural wood resins are usually complex mixtures consisting of various compounds. Therefore, effective chemical characterization methods are necessary for the research and quality control of natural wood resins. No need for separation or labeling, wood resin samples can be measured directly by Fourier transform infrared (FT-IR) spectroscopy, which reduces the testing costs and avoids the possible distortions caused by the pretreatments. However, the absorption bands of various compositions in the resin sample are assembled in a single spectrum by the separation-free measurement, which makes it difficult to identify the compounds of interest and decreases the limits of detection. In this research, the temperature-resolved and space-resolved FT-IR techniques are proposed to resolve the overlapped signals for the direct, selective, and sensitive characterization of natural wood resins. For resin exudates, the temperature-resolved FT-IR spectroscopy and two-dimensional correlation analysis can resolve the absorption bands of different compounds according to their responses to the thermal perturbations. For resin-containing woods, the FT-IR microspectroscopic imaging and principal component analysis can resolve the absorption bands of different compounds according to their positions. The study of six kinds of wood resins proves the feasibility of temperature-resolved and space-resolved FT-IR techniques for the direct, selective, and sensitive chemical characterization of natural wood resins.

  11. Characterization of microflora and transformation of organic matters in urban sewer system.

    PubMed

    Jin, Pengkang; Wang, Bin; Jiao, Ding; Sun, Guangxi; Wang, Baobao; Wang, Xiaochang C

    2015-11-01

    A study was conducted using a pilot sewer system consisting of 35 sequential sections, totalling 1200 m of gravity pipe. Urban sewage flowed into the sewer system at a constant flow rate until it reached physical and microbiological steady states. Microflora in the biofilm that attached to the inner surface along the pipe length were analysed. The organic compositions in both the liquid and gaseous phases of the sewer system were monitored. The results showed that typical fermentation bacteria, such as bacteroidetes and bacillus, were abundant in the system, indicating that the anoxic environment (DO = 0.3 mg/L) was suitable for fermentative bacterial growth. This resulted in a substantial reduction of the chemical oxygen demand (COD) along the pipe length and an increase of the biodegradable oxygen demand/chemical oxygen demand (BOD/COD) ratio from 0.68 at the beginning of the sewer system to 0.84 at the end of the sewer system; this was an indication of a transformation of organic matters from less-biodegradable to more-biodegradable products. Via molecular weight (MW) analysis, it was further identified that the larger organic molecules (MW > 10,000 Da) were transformed into products with smaller molecular weights. Regarding the fermentation products, the concentrations of the volatile fatty acids (VFAs) increased dramatically in the initial 600-m sections and then remained constant for the later sections except for the end section of the sewer; acetic acid was found to be the primary product of the VFAs. Gaseous carbon dioxide (CO2) and methane (CH4) were found to increase along the length of the sewer system, whereas the concentrations of ethanol, lactic acid, and hydrogen (H2) were high at the beginning of the sewer and then decreased in the rear sections of the sewer system. It could thus be concluded that in an urban wastewater sewer system, fermentative microflora could perform important roles in contributing to organic matter removal and

  12. Toxicological characterization of 2,4,6-trinitrotoluene, its transformation products, and two nitramine explosives.

    PubMed

    Neuwoehner, Judith; Schofer, Andrea; Erlenkaemper, Bibiane; Steinbach, Klaus; Hund-Rinke, T Kerstin; Eisentraeger, Adolf

    2007-06-01

    The soil and groundwater of former ordnance plants and their dumping sites have often been highly contaminated with the explosive 2,4,6-trinitrotoluene (2,4,6-TNT) leading to a potential hazard for humans and the environment. Further hazards can arise from metabolites of transformation, by-products of the manufacturing process, or incomplete combustion. This work examines the toxicity of polar nitro compounds relative to their parent compound 2,4,6-TNT using four different ecotoxicological bioassays (algae growth inhibition test, daphnids immobilization test, luminescence inhibition test, and cell growth inhibition test), three genotoxicological assays (umu test, NM2009 test, and SOS Chromotest), and the Ames fluctuation test for detection of mutagenicity. For this study, substances typical for certain steps of degradation/transformation of 2,4,6-TNT were chosen for investigation. This work determines that the parent compounds 2,4,6-TNT and 1,3,5-trinitrobenzene are the most toxic substances followed by 3,5-dinitrophenol, 3,5-dinitroaniline and 4-amino-2-nitrotoluene. Less toxic are the direct degradation products of 2,4,6-TNT like 2,4-dinitrotoluene, 2,6-dinitrotoluene, 2-amino-4,6-dinitrotoluene, and 4-amino-2,6-dinitrotoluene. A weak toxic potential was observed for 2,4,6-trinitrobenzoic acid, 2,4-diamino-6-nitrotoluene, 2,4-dinitrotoluene-5-sulfonic acid, and 2,6-diamino-4-nitrotoluene. Octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine and hexahydro-1,3,5-trinitro-l,3,5-triazine show no hint of acute toxicity. Based on the results of this study, we recommend expanding future monitoring programs of not only the parent substances but also potential metabolites based on conditions at the contaminated sites and to use bioassays as tools for estimating the toxicological potential directly by testing environmental samples. Site-specific protocols should be developed. If hazardous substances are found in relevant concentrations, action should be taken to prevent

  13. Characterizing microstructural changes of skeletal muscle tissues using spectral transformed Mueller matrix polarization parameters

    NASA Astrophysics Data System (ADS)

    He, Chao; He, Honghui; Chang, Jintao; Ma, Hui

    2016-03-01

    Polarization imaging techniques are recognized as potentially powerful tools to detect the structural changes of biological tissues. Meanwhile, spectral features of the scattered light can also provide abundant microstructural information, therefore can be applied in biomedical studies. In this paper, we adopt the polarization reflectance spectral imaging to analyze the microstructural changes of hydrolyzing skeletal muscle tissues. We measure the Mueller matrix, which is a comprehensive description of the polarization properties, of the bovine skeletal muscle samples in different periods of time, and analyze its behavior using the multispectral Mueller matrix transformation (MMT) technique. The experimental results show that for bovine skeletal muscle tissues, the backscattered spectral MMT parameters have different values and variation features at different stages. We can also find the experimental results indicate that the stages of hydrolysis for bovine skeletal muscle samples can be judged by the spectral MMT parameters. The results presented in this work show that combining with the spectral technique, the MMT parameters have the potential to be used as tools for meat quality detection and monitoring.

  14. Characterizing microstructures of cancerous tissues using multispectral transformed Mueller matrix polarization parameters.

    PubMed

    He, Chao; He, Honghui; Chang, Jintao; Dong, Yang; Liu, Shaoxiong; Zeng, Nan; He, Yonghong; Ma, Hui

    2015-08-01

    In this paper, we take the transmission 3 × 3 linear polarization Mueller matrix images of the unstained thin slices of human cervical and thyroid cancer tissues, and analyze their multispectral behavior using the Mueller matrix transformation (MMT) parameters. The experimental results show that for both cervical and thyroid cancerous tissues, the characteristic features of multispectral transmitted MMT parameters can be used to distinguish the normal and abnormal areas. Moreover, Monte Carlo simulations based on the sphere-cylinder birefringence model (SCBM) provide additional information of the relations between the characteristic spectral features of the MMT parameters and the microstructures of the tissues. Comparisons between the experimental and simulated data confirm that the contrast mechanism of the transmission MMT imaging for cancer detection is the breaking down of birefringent normal tissues for cervical cancer, or the formation of birefringent surrounding structures accompanying the inflammatory reaction for thyroid cancer. It is also testified that, the characteristic spectral features of polarization imaging techniques can provide more detailed microstructural information of tissues for diagnosis applications. PMID:26309757

  15. Characterization of soft magnetic material Metglas 2605S-3A for power applications and transformers

    SciTech Connect

    Wieserman, W.R.; Kusic, G.L.

    1995-10-01

    This experimental study separates the hysteresis, eddy current, and electromechanical motion losses of a soft magnetic material for electric power energy conversion applications. Mechanical responses of the magnetic material to sine and square wave voltage excitation are compared. Commercially available, Metglas 2605S3-A tape cores were evaluated up to 300 C for sine wave and square wave voltage excitation frequencies 1--100 kHz. Data presented illustrates the effects of maximum flux density, frequency, waveshape, and temperature on the specific core loss and size and shape of the B-H loops. Relative losses play a major role in material selection for electronic and electric power applications including power converters, transformers, controllers, and filter elements. Dynamic measurements of the magnetostrictive response of these specific toroidal test cores were made using a sensitive, capacitive probe and a unique application of frequency modulation. The dynamic behavior of the toroidal test cores and the related unusual B-H loop characteristics were compared to results obtained by an electromechanical model.

  16. Fourier transform infrared absorption spectroscopy characterization of gaseous atmospheric pressure plasmas with 2 mm spatial resolution

    SciTech Connect

    Laroche, G.; Vallade, J.; Bazinette, R.; Hernandez, E.; Hernandez, G.; Massines, F.; Nijnatten, P. van

    2012-10-15

    This paper describes an optical setup built to record Fourier transform infrared (FTIR) absorption spectra in an atmospheric pressure plasma with a spatial resolution of 2 mm. The overall system consisted of three basic parts: (1) optical components located within the FTIR sample compartment, making it possible to define the size of the infrared beam (2 mm Multiplication-Sign 2 mm over a path length of 50 mm) imaged at the site of the plasma by (2) an optical interface positioned between the spectrometer and the plasma reactor. Once through the plasma region, (3) a retro-reflector module, located behind the plasma reactor, redirected the infrared beam coincident to the incident path up to a 45 Degree-Sign beamsplitter to reflect the beam toward a narrow-band mercury-cadmium-telluride detector. The antireflective plasma-coating experiments performed with ammonia and silane demonstrated that it was possible to quantify 42 and 2 ppm of these species in argon, respectively. In the case of ammonia, this was approximately three times less than this gas concentration typically used in plasma coating experiments while the silane limit of quantification was 35 times lower. Moreover, 70% of the incoming infrared radiation was focused within a 2 mm width at the site of the plasma, in reasonable agreement with the expected spatial resolution. The possibility of reaching this spatial resolution thus enabled us to measure the gaseous precursor consumption as a function of their residence time in the plasma.

  17. Characterizing microstructures of cancerous tissues using multispectral transformed Mueller matrix polarization parameters

    PubMed Central

    He, Chao; He, Honghui; Chang, Jintao; Dong, Yang; Liu, Shaoxiong; Zeng, Nan; He, Yonghong; Ma, Hui

    2015-01-01

    In this paper, we take the transmission 3 × 3 linear polarization Mueller matrix images of the unstained thin slices of human cervical and thyroid cancer tissues, and analyze their multispectral behavior using the Mueller matrix transformation (MMT) parameters. The experimental results show that for both cervical and thyroid cancerous tissues, the characteristic features of multispectral transmitted MMT parameters can be used to distinguish the normal and abnormal areas. Moreover, Monte Carlo simulations based on the sphere-cylinder birefringence model (SCBM) provide additional information of the relations between the characteristic spectral features of the MMT parameters and the microstructures of the tissues. Comparisons between the experimental and simulated data confirm that the contrast mechanism of the transmission MMT imaging for cancer detection is the breaking down of birefringent normal tissues for cervical cancer, or the formation of birefringent surrounding structures accompanying the inflammatory reaction for thyroid cancer. It is also testified that, the characteristic spectral features of polarization imaging techniques can provide more detailed microstructural information of tissues for diagnosis applications. PMID:26309757

  18. Ultrasonic characterization of soft tissue vibrations based on the two-dimensional Fourier transform

    NASA Astrophysics Data System (ADS)

    Sikdar, Siddhartha; Kim, Yongmin; Beach, Kirk W.

    2005-09-01

    It has recently been demonstrated that soft tissue vibrations in the body, traditionally associated with vascular bruits and cardiac murmurs, can potentially be used for the ultrasonic diagnosis of coronary artery disease and vascular trauma. In this paper, the ultrasonic spectrum of soft tissue vibrations is formulated using the two-dimensional Fourier transform, making full use of the information present in the backscattered ultrasound echoes from vibrating tissue. Parametric simulation studies show that vibrations with amplitude 1 μm may be detected even with tissue velocity of 20 cm/s and acceleration of 5 m/s2, e.g., during peak cardiac motion. Vibrations with amplitude as low as 0.1 μm may be detected when the tissue acceleration is negligible, e.g., during mid-diastole. Also, it was found that tissue vibrations in a direction transverse to the ultrasound beam can be detected. In vivo examples of cardiac wall vibrations in patients with coronary artery disease are presented. Tissue vibrations can provide improved sensitivity over conventional duplex ultrasound since the scattering strength from tissue is significantly higher than that from blood. In addition, detection of tissue vibrations has reduced angle dependency and does not require visualization of the vessel lumen, making the exam less dependent on operator skill.

  19. Characterizing the transformation and transfer of nitrogen during the aerobic treatment of organic wastes and digestates

    SciTech Connect

    Zeng Yang; Guardia, Amaury de; Daumoin, Mylene; Benoist, Jean-Claude

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Ammonia emissions varied depending on the nature of wastes and the treatment conditions. Black-Right-Pointing-Pointer Nitrogen losses resulted from ammonia emissions and nitrification-denitrification. Black-Right-Pointing-Pointer Ammonification can be estimated from biodegradable carbon and carbon/nitrogen ratio. Black-Right-Pointing-Pointer Ammonification was the main process contributing to N losses. Black-Right-Pointing-Pointer Nitrification rate was negatively correlated to stripping rate of ammonia nitrogen. - Abstract: The transformation and transfer of nitrogen during the aerobic treatment of seven wastes were studied in ventilated air-tight 10-L reactors at 35 Degree-Sign C. Studied wastes included distinct types of organic wastes and their digestates. Ammonia emissions varied depending on the kind of waste and treatment conditions. These emissions accounted for 2-43% of the initial nitrogen. Total nitrogen losses, which resulted mainly from ammonia emissions and nitrification-denitrification, accounted for 1-76% of the initial nitrogen. Ammonification was the main process responsible for nitrogen losses. An equation which allows estimating the ammonification flow of each type of waste according to its biodegradable carbon and carbon/nitrogen ratio was proposed. As a consequence of the lower contribution of storage and leachate rates, stripping and nitrification rates of ammonia nitrogen were negatively correlated. This observation suggests the possibility of promotingnitrification in order to reduce ammonia emissions.

  20. Identification and characterization of tebuconazole transformation products in soil by combining suspect screening and molecular typology.

    PubMed

    Storck, Veronika; Lucini, Luigi; Mamy, Laure; Ferrari, Federico; Papadopoulou, Evangelia S; Nikolaki, Sofia; Karas, Panagiotis A; Servien, Remi; Karpouzas, Dimitrios G; Trevisan, Marco; Benoit, Pierre; Martin-Laurent, Fabrice

    2016-01-01

    Pesticides generate transformation products (TPs) when they are released into the environment. These TPs may be of ecotoxicological importance. Past studies have demonstrated how difficult it is to predict the occurrence of pesticide TPs and their environmental risk. The monitoring approaches mostly used in current regulatory frameworks target only known ecotoxicologically relevant TPs. Here, we present a novel combined approach which identifies and categorizes known and unknown pesticide TPs in soil by combining suspect screening time-of-flight mass spectrometry with in silico molecular typology. We used an empirical and theoretical pesticide TP library for compound identification by both non-target and target time-of-flight (tandem) mass spectrometry, followed by structural proposition through a molecular structure correlation program. In silico molecular typology was then used to group TPs according to common molecular descriptors and to indirectly elucidate their environmental parameters by analogy to known pesticide compounds with similar molecular descriptors. This approach was evaluated via the identification of TPs of the triazole fungicide tebuconazole occurring in soil during a field dissipation study. Overall, 22 empirical and 12 yet unknown TPs were detected, and categorized into three groups with defined environmental properties. This approach combining suspect screening time-of-flight mass spectrometry with molecular typology could be extended to other organic pollutants and used to rationalize the choice of TPs to be investigated towards a more comprehensive environmental risk assessment scheme. PMID:26552540

  1. XAFS characterization of industrial catalysts: in situ study of phase transformation of nickel sulfide

    NASA Astrophysics Data System (ADS)

    Wang, J.; Jia, Z.; Wang, Q.; Zhao, S.; Xu, Z.; Yang, W.; Frenkel, A. I.

    2016-05-01

    The online sulfiding process for nickel-contained catalyst often ends up with a nickel sulfide mixture in refinery plant. To elucidate the local environment of nickel and its corresponding sulfur species, a model catalyst (nickel sulfide) and model thermal process were employed to explore the possibilities for characterization of real catalysts in industrial conditions. The present investigation shows effectiveness of in situ XANES and EXAFS measurements for studying the phase stability and phase composition in these systems, which could be used to simulate real sulfiding process in industrial reactions, such as hydrodesulfurizations of oil.

  2. Characterization of near-terahertz complementary metal-oxide semiconductor circuits using a Fourier-transform interferometer.

    PubMed

    Arenas, D J; Shim, Dongha; Koukis, D I; Seok, Eunyoung; Tanner, D B; O, Kenneth K

    2011-10-01

    Optical methods for measuring of the emission spectra of oscillator circuits operating in the 400-600 GHz range are described. The emitted power from patch antennas included in the circuits is measured by placing the circuit in the source chamber of a Fourier-transform interferometric spectrometer. The results show that this optical technique is useful for measuring circuits pushing the frontier in operating frequency. The technique also allows the characterization of the circuit by measuring the power radiated in the fundamental and in the harmonics. This capability is useful for oscillator architectures designed to cancel the fundamental and use higher harmonics. The radiated power was measured using two techniques: direct measurement of the power by placing the device in front of a bolometer of known responsivity, and by comparison to the estimated power from blackbody sources. The latter technique showed that these circuits have higher emission than blackbody sources at the operating frequencies, and, therefore, offer potential spectroscopy applications. PMID:22047279

  3. Characterization of near-terahertz complementary metal-oxide semiconductor circuits using a Fourier-transform interferometer

    SciTech Connect

    Arenas, D. J.; Shim, Dongha; Koukis, D. I.; Seok, Eunyoung; Tanner, D. B.; O, Kenneth K.

    2011-10-24

    Optical methods for measuring of the emission spectra of oscillator circuits operating in the 400-600 GHz range are described. The emitted power from patch antennas included in the circuits is measured by placing the circuit in the source chamber of a Fourier-transform interferometric spectrometer. The results show that this optical technique is useful for measuring circuits pushing the frontier in operating frequency. The technique also allows the characterization of the circuit by measuring the power radiated in the fundamental and in the harmonics. This capability is useful for oscillator architectures designed to cancel the fundamental and use higher harmonics. The radiated power was measured using two techniques: direct measurement of the power by placing the device in front of a bolometer of known responsivity, and by comparison to the estimated power from blackbody sources. The latter technique showed that these circuits have higher emission than blackbody sources at the operating frequencies, and, therefore, offer potential spectroscopy applications.

  4. Characterization of RNA from Noninfectious Virions Produced by Sarcoma Positive-Leukemia Negative Transformed 3T3 Cells

    PubMed Central

    Phillips, Leo A.; Hollis, Vincent W.; Bassin, Robert H.; Fischinger, Peter J.

    1973-01-01

    RNA from noninfectious virions produced by two established clonal lines of sarcoma positive-leukemia negative (S+L-)-transformed 3T3 cells has been characterized. RNA from virions or nucleoids of S+L--(C243) cells consisted of three to four sizes: ±44 S (6%), 28 S (17%), 18 S (38%), and <18 S (39%). 28S virion RNA contained some virus-specific information demonstrable by RNA·DNA hybridization with a DNA probe derived from the RNA-directed DNA polymerase product of murine sarcoma-leukemia virus, while parallel studies indicated that 28S ribosomal RNA from ribosomal subunits of transformed and nontransformed 3T3 cells did not contain virus-specific information. In contrast to the S+L-(C243) virions, RNA from virions or nucleoids of S+L-(D56) cells consisted of five sizes: 80 S (6%), 68 S (8%), 56 S (5%), 28 S (28%), and <28 S (53%). Thermal dissociation studies suggested that this S+L- genome is comprised of 28S RNA subunits. From these studies we postulate that the 28S viral RNA is most probably the monomeric genome of S+L- virions. PMID:4355380

  5. Synthesis of lead zirconate titanate nanofibres and the Fourier-transform infrared characterization of their metallo-organic decomposition process

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Santiago-Avilés, Jorge J.

    2004-01-01

    We have synthesized Pb(Zr0.52Ti0.48)O3 fibres with diameters ranging from 500 nm to several microns using electrospinning and metallo-organic decomposition techniques (Wang et al 2002 Mater. Res. Soc. Symp. Proc. 702 359). By a refinement of our electrospinning technique, i.e. by increasing the viscosity of the precursor solution, and by adding a filter to the tip of the syringe, the diameter of the synthesized PZT fibres has been reduced to the neighbourhood of 100 nm. The complex thermal decomposition was characterized using Fourier-transform infrared (FTIR) spectroscopy and x-ray diffraction (XRD). It was found that alcohol evaporated during electrospinning and that most of the organic groups had pyrolysed before the intermediate pyrochlore phase was formed. There is a good correspondence between XRD and FTIR spectra. We also verify that a thin film of platinum coated on the silicon substrate catalyses the phase transformation of the pyrochlore into the perovskite phase.

  6. Development and testing of a fast Fourier transform high dynamic-range spectral diagnostics for millimeter wave characterization

    NASA Astrophysics Data System (ADS)

    Thoen, D. J.; Bongers, W. A.; Westerhof, E.; Oosterbeek, J. W.; de Baar, M. R.; van den Berg, M. A.; van Beveren, V.; Bürger, A.; Goede, A. P. H.; Graswinckel, M. F.; Hennen, B. A.; Schüller, F. C.

    2009-10-01

    A fast Fourier transform (FFT) based wide range millimeter wave diagnostics for spectral characterization of scattered millimeter waves in plasmas has been successfully brought into operation. The scattered millimeter waves are heterodyne downconverted and directly digitized using a fast analog-digital converter and a compact peripheral component interconnect computer. Frequency spectra are obtained by FFT in the time domain of the intermediate frequency signal. The scattered millimeter waves are generated during high power electron cyclotron resonance heating experiments on the TEXTOR tokamak and demonstrate the performance of the diagnostics and, in particular, the usability of direct digitizing and Fourier transformation of millimeter wave signals. The diagnostics is able to acquire 4 GHz wide spectra of signals in the range of 136-140 GHz. The rate of spectra is tunable and has been tested between 200 000 spectra/s with a frequency resolution of 100 MHz and 120 spectra/s with a frequency resolution of 25 kHz. The respective dynamic ranges are 52 and 88 dB. Major benefits of the new diagnostics are a tunable time and frequency resolution due to postdetection, near-real time processing of the acquired data. This diagnostics has a wider application in astrophysics, earth observation, plasma physics, and molecular spectroscopy for the detection and analysis of millimeter wave radiation, providing high-resolution spectra at high temporal resolution and large dynamic range.

  7. Development and testing of a fast Fourier transform high dynamic-range spectral diagnostics for millimeter wave characterization.

    PubMed

    Thoen, D J; Bongers, W A; Westerhof, E; Oosterbeek, J W; de Baar, M R; van den Berg, M A; van Beveren, V; Bürger, A; Goede, A P H; Graswinckel, M F; Hennen, B A; Schüller, F C

    2009-10-01

    A fast Fourier transform (FFT) based wide range millimeter wave diagnostics for spectral characterization of scattered millimeter waves in plasmas has been successfully brought into operation. The scattered millimeter waves are heterodyne downconverted and directly digitized using a fast analog-digital converter and a compact peripheral component interconnect computer. Frequency spectra are obtained by FFT in the time domain of the intermediate frequency signal. The scattered millimeter waves are generated during high power electron cyclotron resonance heating experiments on the TEXTOR tokamak and demonstrate the performance of the diagnostics and, in particular, the usability of direct digitizing and Fourier transformation of millimeter wave signals. The diagnostics is able to acquire 4 GHz wide spectra of signals in the range of 136-140 GHz. The rate of spectra is tunable and has been tested between 200,000 spectra/s with a frequency resolution of 100 MHz and 120 spectra/s with a frequency resolution of 25 kHz. The respective dynamic ranges are 52 and 88 dB. Major benefits of the new diagnostics are a tunable time and frequency resolution due to postdetection, near-real time processing of the acquired data. This diagnostics has a wider application in astrophysics, earth observation, plasma physics, and molecular spectroscopy for the detection and analysis of millimeter wave radiation, providing high-resolution spectra at high temporal resolution and large dynamic range. PMID:19895061

  8. Characterization of naphthenic acids by gas chromatography-Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Ortiz, Xavier; Jobst, Karl J; Reiner, Eric J; Backus, Sean M; Peru, Kerry M; McMartin, Dena W; O'Sullivan, Gwen; Taguchi, Vince Y; Headley, John V

    2014-08-01

    During the bitumen extraction from the oil sands of Alberta, large volumes of process water containing naphthenic acids are stored in tailing ponds. The naphthenic acids along with other components in the processed waters are known to be toxic in aquatic environments. In view of the complex matrix and the toxicity of the processed waters, there is a need for complementary analytical techniques for comprehensive characterization of the naphthenic acid mixtures. This study reports the online gas chromatographic separation of naphthenic acid mixtures prior to ultrahigh resolution mass spectrometry detection, using electron and chemical ionization. Two oil sands processed water samples and two groundwater samples were characterized to evaluate the performance of the instrumental technique. The high mass resolution of the system enabled visualization of the data using Kendrick mass defect plots. The addition of gas chromatographic separations enabled visualization of the data as unique compound class elution fingerprints. The technique is demonstrated to be a valuable tool for chemical fingerprinting of naphthenic acids. PMID:25001115

  9. CT angiography after 20 years: a transformation in cardiovascular disease characterization continues to advance.

    PubMed

    Rubin, Geoffrey D; Leipsic, Jonathon; Joseph Schoepf, U; Fleischmann, Dominik; Napel, Sandy

    2014-06-01

    Through a marriage of spiral computed tomography (CT) and graphical volumetric image processing, CT angiography was born 20 years ago. Fueled by a series of technical innovations in CT and image processing, over the next 5-15 years, CT angiography toppled conventional angiography, the undisputed diagnostic reference standard for vascular disease for the prior 70 years, as the preferred modality for the diagnosis and characterization of most cardiovascular abnormalities. This review recounts the evolution of CT angiography from its development and early challenges to a maturing modality that has provided unique insights into cardiovascular disease characterization and management. Selected clinical challenges, which include acute aortic syndromes, peripheral vascular disease, aortic stent-graft and transcatheter aortic valve assessment, and coronary artery disease, are presented as contrasting examples of how CT angiography is changing our approach to cardiovascular disease diagnosis and management. Finally, the recently introduced capabilities for multispectral imaging, tissue perfusion imaging, and radiation dose reduction through iterative reconstruction are explored with consideration toward the continued refinement and advancement of CT angiography. PMID:24848958

  10. Long-term batch study of sorption, transformation and extractability to characterize the fate of the veterinary antibiotic sulfadiazine

    NASA Astrophysics Data System (ADS)

    Sittig, Stephan; Kasteel, Roy; Groeneweg, Joost; Vereecken, Harry

    2010-05-01

    The occurrence of veterinary antibiotic substances in various environmental compartments is of growing concern. Once released into the environment (e.g. via manure), these organic substances can cause changes in the composition of microbial populations, provoke the development and spreading of resistance genes and finally reach the food chain. The substance under study is the veterinary antibiotic sulfadiazine (SDZ), which belongs to the chemical group of the sulfonamides. These compounds are widely applied in animal husbandry. There are hardly any studies on the macroscopic sorption and desorption behaviour in combination with transformation processes, particularly investigating the sorbed fraction. We are conducting long-term batch sorption experiments to characterize the partitioning between the liquid and the solid phases as well as formation of transformation products. A sequential extraction procedure enables us to analyse the composition of the various sorbed fractions. We applied 14C-labelled SDZ in aqueous solution to fresh soil, originating from an agricultural field (silty loam). Adsorption and desorption studies are conducted for the duration of 60 d and 80 d, respectively. Unique setups for single time-steps allow us to trace the development of the partition process between the liquid and the solid phase and also partitioning within the solid phase. The composition of these liquid phases concerning the parent substance and the transformation products is analyzed. Using Radio-HPLC we find at least five transformation products: 4-hydroxy-sulfadiazine (4-OH-SDZ), 4-(2-iminopyrimidin-1(2H)-yl)-aniline (An-SDZ) and additionally three yet unknown products. By means of a sequential extraction, differently strong bound fractions of the compound can be distinguished. Extractions consist of a mild method (0.01 M CaCl2-solution; 24 h) followed by a methanol extraction (4 h). Finally, a residual fraction is gained by microwave extraction at an elevated temperature

  11. Phasor transform to extract glucose and ascorbic acid data in an amperometric sensor.

    PubMed

    Iyengar, S; Hall, E A

    2000-11-01

    A method for separating the signals from glucose and ascorbic acid on a single recognition surface using an ac immittance technique is presented. It is proposed that each oxidation process can be represented by a unique vector based on psi and YO, and that the concentration of each analyte can be determined by monitoring the change in the admittance magnitude in the direction of the characteristic angle for that particular species. The total Faradaic admittance (YF,total) for all electroactive species present is given by a linear combination of the independent vectors from the different species. In the system tested, the analytes are glucose and ascorbic acid, the former being estimated via the measurand, hydrogen peroxide. Thus, one of the electroactive species (hydrogen peroxide) is not a bulk solution species, but is 'generated' in the enzyme matrix. The admittance measurements from ascorbic acid and the enzyme-generated hydrogen peroxide showed the characteristic phase angles of each oxidation signal, allowing for good spatial resolution. The behaviour of each of these analytes is presented and calibration curves tested. Based on the calibration curves and the basis vectors, samples containing both glucose and ascorbic acid were measured by transforming the measured total admittance from the complex Cartesian space into 'analyte space', where the X-Y axes are given by the basis vectors ŷEGHP,GOD and ŷAA,GOD, respectively. PMID:11193087

  12. DNA binding to crystalline silica characterized by Fourier-transform infrared spectroscopy.

    PubMed Central

    Mao, Y; Daniel, L N; Whittaker, N; Saffiotti, U

    1994-01-01

    The interaction of DNA with crystalline silica in buffered aqueous solutions at physiologic pH has been investigated by Fourier-transform infrared spectroscopy (FT-IR). In aqueous buffer, significant changes occur in the spectra of DNA and silica upon coincubation, suggesting that a DNA-silica complex forms as silica interacts with DNA. As compared to the spectrum of silica alone, the changes in the FT-IR spectrum of silica in the DNA-silica complex are consistent with an Si-O bond perturbation on the surface of the silica crystal. DNA remains in a B-form conformation in the DNA-silica complex. The most prominent changes in the DNA spectrum occur in the 1225 to 1000 cm-1 region. Upon binding, the PO2- asymmetric stretch at 1225 cm-1 is increased in intensity and slightly shifted to lower frequencies; the PO2- symmetric stretch at 1086 cm-1 is markedly increased in intensity and the band at 1053 cm-1, representing either the phosphodiester or the C-O stretch of DNA backbone, is significantly reduced in intensity. In D2O buffer, the DNA spectrum reveals a marked increase in intensity of the peak at 1086 cm-1 and a progressive decrease in intensity of the peak at 1053 cm-1 when DNA is exposed to increasing concentrations of silica. The carbonyl band at 1688 cm-1 diminishes and shifts to slightly lower frequencies with increasing concentrations of silica. The present study demonstrates that crystalline silica binds to the phosphate-sugar backbone of DNA.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7705292

  13. Capillary HPLC/QTOF-MS for characterizing complex naphthenic acid mixtures and their microbial transformation.

    PubMed

    Bataineh, M; Scott, A C; Fedorak, P M; Martin, J W

    2006-12-15

    A rapidly expanding oil sands industry in Canada produces and indefinitely stores large volumes of toxic aqueous tailings containing high concentrations of naphthenic acids (NAs), a complex mixture of naturally occurring aliphatic or alicyclic carboxylic acids. Although there is an acknowledged need to reduce the environmental risks posed by NAs, little is understood about their environmental fate due to a lack of appropriate analytical methods. A dilute-and-shoot reversed-phase capillary HPLC/QTOF-MS method was developed that combines high specificity and sensitivity, quantitative capabilities, the ability to detect novel transformation products, and new structural information within each NA isomer class. HPLC separated NAs, based on carbon number, degree of cyclization, and the extent of alkyl branching, and in so doing increased analytical sensitivity up to 350-fold while providing additional specificity compared to infusion techniques. For tailings water, an interlaboratory study revealed many differences in isomer class profiles compared to an established GC/MS method, much of which was attributed to the misclassification of oxidized NAs (i.e., NA + O) by low-resolution GC/MS. HPLC/QTOF-MS enabled the detection of oxidized products in the same chromatographic run, and Van Krevelen diagrams were adapted to visualize the complex data. A marked decrease of retention times was evident in Syncrude tailings water compared to a commercial mixture, suggesting that tailings water is dominated by highly persistent alkyl-substituted isomers. A biodegradation study revealed that tailings water microorganisms preferentially deplete the least alkyl-substituted fraction and may be responsible for the NA profile in aged tailings water. PMID:17165827

  14. Fourier transform infrared spectroscopy (FTIR) characterization of the interaction of anti-cancer photosensitizers with dendrimers.

    PubMed

    Dabrzalska, Monika; Benseny-Cases, Nuria; Barnadas-Rodríguez, Ramon; Mignani, Serge; Zablocka, Maria; Majoral, Jean-Pierre; Bryszewska, Maria; Klajnert-Maculewicz, Barbara; Cladera, Josep

    2016-01-01

    The systemic or local administration of a photosensitizer for photodynamic therapy is highly limited by poor selectivity, rapid deactivation and long-lasting skin toxicity due to unfavorable biodistribution. Drug delivery systems based on nanocarriers may help specific and effective delivery of photosensitizers. In the present paper, the interaction of two photosensitizers, methylene blue and rose bengal, with phosphorous cationic and anionic dendrimers as potential nanocarriers, has been characterized. A novel method is presented based on the analysis of the infrared spectra of mixtures of photosensitizer and dendrimer. The capacity of dendrimers to bind the photosensitizers has been evaluated by obtaining the corresponding binding curves. It is shown that methylene blue interacts with both cationic and anionic dendrimers, whereas rose bengal only binds to the cationic ones. Dendrimers are shown to be potential nanocarriers for a specific delivery of both photosensitizers. PMID:26507333

  15. In situ monitoring, separation, and characterization of gold nanorod transformation during seed-mediated synthesis.

    PubMed

    Nguyen, Thao M; Pettibone, John M; Gigault, Julien; Hackley, Vincent A

    2016-03-01

    The control of gold nanorod (GNR) solution-based syntheses has been hindered in part by the inability to examine and control the conversion of precursor seed populations to anisotropic materials, which have resulted in low yields of desired products and limited their commercial viability. The advantages offered by tandem separation and characterization methods utilizing asymmetric-flow field flow fractionation (A4F) are principally achieved as a result of their non-disruptive nature (minimizing artefacts), fast throughput, and in-situ analysis. With hyphenated A4F methods, resolved populations of seeds and secondary products, up to long aspect ratio rods, have been achieved and exemplify progress towards elucidating mechanistic aspects of formation and thus rational design. While there have been previously reported studies on A4F separation of GNRs, to our knowledge, this is the first published investigation of in situ GNR growth, separation, and characterization based on A4F, where its utilization in this capacity goes beyond traditional separation analysis. By using hydroquinone as the reducing agent, the conversion of the initial seed population to a distribution of products, including the GNRs, could be monitored in real time using A4F hyphenated with a diode array detector. Transmission electron microscopy confirms that the number of peaks observed during fractionation corresponds with size and shape dispersity. This proof-of-principle study introduces A4F as a technique that establishes a foundation for future mechanistic studies on the growth of GNRs from gold seeds, including conversion of the seed population to initial products, a topic highly relevant to advancing progress in nanomanufacturing. Graphical Abstract ᅟ. PMID:26873210

  16. Parametric study and characterization of the isobaric thermomechanical transformation fatigue of nickel-rich NiTi SMA actuators

    NASA Astrophysics Data System (ADS)

    Bertacchini, Olivier W.; Schick, Justin; Lagoudas, Dimitris C.

    2009-03-01

    The recent development of various aerospace applications utilizing Ni-rich NiTi Shape memory Alloys (SMAs) as actuators motivated the need to characterize the cyclic response and the transformation fatigue behavior of such alloys. The fatigue life validation and certification of new designs is required in order to be implemented and used in future applications. For that purpose, a custom built fatigue test frame was designed to perform isobaric thermally induced transformation cycles on small dogbones SMA actuators (test gauge cross-section up to: 1.270 x 0.508 mm2). A parametric study on the cyclic response and transformation fatigue behavior of Ni-rich NiTi SMAs led to the optimization of several material/process and test parameters, namely: the applied stress range, the heat treatment, the heat treatment environment and the specimen thickness. However, fatigue testing was performed in a chilled waterless glycol environment maintained at a temperature of 5°C that showed evidence of corrosion-assisted transformation fatigue failure. Therefore, it was necessary to build a fatigue test frame that would employ a dry and inert cooling methodology to get away from any detrimental interactions between the specimens and the cooling medium (corrosion). The selected cooling method was gaseous nitrogen, sprayed into a thermally insulated chamber, maintaining a temperature of -20°C. The design of the gaseous nitrogen cooling was done in such a way that the actuation frequency is similar to the one obtained using the original design (~ 0.1 Hz). For both cooling methods, Joule resistive heating was used to heat the specimens. In addition and motivated by the difference in surface quality resulting from different material processing such as EDM wire cutting and heat treatments, EDM recast layer and oxide layer were removed. The removal was followed by an ultra-fine polish (0.05 μm) that was performed on a subset of the fatigue specimens. Experimental results are presented

  17. Physical Characterization of human centromeric regions using transformation-associated recombination cloning technology

    SciTech Connect

    Vladimir Larionov, Ph D

    2007-06-05

    A special interest in the organization of human centromeric DNA was stimulated a few years ago when two independent groups succeeded in reconstituting a functional human centromere, using constructs carrying centromere-specific alphoid DNA arrays. This work demonstrated the importance of DNA components in mammalian centromeres and opened a way for studying the structural requirements for de novo kinetochore formation and for construction of human artificial chromosomes (HACs) with therapeutic potential. To elucidate the structural requirements for formation of HACs with a functional kinetochore, we developed a new method for cloning of large DNA fragments for human centromeric regions that can be used as a substrate for HAC formation. This method exploits in vivo recombination in yeast (TAR cloning). In addition, a new strategy for the construction of alphoid DNA arrays was developed in our lab. The strategy involves the construction of uniform or hybrid synthetic alphoid DNA arrays by the RCA-TAR technique. This technique comprises two steps: rolling circle amplification of an alphoid DNA dimer and subsequent assembling of the amplified fragments by in vivo homologous recombination in yeast (Figure 1). Using this system, we constructed a set of different synthetic alphoid DNA arrays with a predetermined sequence varying in size from 30 to 140 kb and demonstrated that some of the arrays are competent in HAC formation. Because any nucleotide can be changed in a dimer before its amplification, this new technique is optimal for identifying the structural requirements for de novo kinetochore formation in HACs. Moreover, the technique makes possible to introduce into alphoid DNA arrays recognition sites for DNA-binding proteins. We have made the following progress on the studying of human centromeric regions using transformation-associated recombination cloning technology: i) minimal size of alphoid DNA array required for de novo kinetochore formation was estimated; ii

  18. Characterization of full-scale carbon contactors for siloxane removal from biogas using online Fourier transform infrared spectroscopy.

    PubMed

    Hepburn, C A; Martin, B D; Simms, N; McAdam, E J

    2015-01-01

    In this study, online Fourier transform infrared (FTIR) spectroscopy has been used to generate the first comprehensive characterization of full-scale carbon contactors for siloxane removal from biogas. Using FTIR, two clear operational regions within the exhaustion cycle were evidenced: an initial period of pseudo-steady state where the outlet siloxane concentration was consistently below the proposed siloxane limits; and a second period characterized by a progressive rise in outlet siloxane concentration during and after breakthrough. Due to the sharp breakthrough front identified, existing detection methods (which comprise field sampling coupled with laboratory-based chromatographic determination) are insufficiently responsive to define breakthrough, thus carbon contactors currently remain in service while providing limited protection to the combined heat and power engine. Integration of the exhaustion cycle to breakthrough identified average specific media capacities of 8.5-21.5 gsiloxane kg(-1)GAC, which are lower than that has been reported for vapour phase granular activated carbon (GAC). Further speciation of the biogas phase identified co-separation of organic compounds (alkanes and aromatics), which will inevitably reduce siloxane capacity. However, comparison of the five full-scale contactors identified that greater media capacity was accessible through operating contactors at velocities sufficient to diminish axial dispersion effects. In addition to enabling significant insight into gas phase GAC contactors, the use of FTIR for online control of GAC for siloxane removal is also presented. PMID:25413112

  19. Characterization of a water-dispersible metal protective coating with Fourier transform infrared spectroscopy, modulated differential scanning calorimetry, and ellipsometry.

    PubMed

    Boyatzis, Stamatis C; Douvas, Antonios M; Argyropoulos, Vassilike; Siatou, Amalia; Vlachopoulou, Marilena

    2012-05-01

    An ethylene-methacrylic acid copolymer, formulated by BASF as a waterborne suspension of its alkylammonium salt and used, among other applications, in art conservation as a temporary protective coating was characterized using Fourier transform infrared (FT-IR) spectroscopy aided by modulated differential scanning calorimetry (MDSC) and ellipsometry. The thermal conversion of thin copolymer films from the freshly applied state, where carboxylic acid and carboxylate ion functional groups co-exist, to a purely acidic working state was spectroscopically followed. Transmission mid-infrared data of the working state showed a 1 : 12 ratio of methacrylic acid towards ethylene units. The glass transition temperature (T(g)) in the same state was found at 45 °C. Copolymer films spin-coated on mechanically polished bronze and iron coupons were characterized with transflection infrared spectroscopy and compared to corresponding transmission mid-infrared spectra of copolymer films spin-coated on silicon wafers. In the case of bronze coupons, evidence for interaction of the carboxylate ion with the copper substrate was obtained. The chemical structure and the thermal behavior of the coating, as well as some implications on its protective capability towards iron and copper alloys, is discussed as this material has received considerable attention in the field of metal conservation and coatings. PMID:22524964

  20. Fourier Transform Mass Spectrometry and Nuclear Magnetic Resonance Analysis for the Rapid and Accurate Characterization of Hexacosanoylceramide.

    PubMed

    Ross, Charles W; Simonsick, William J; Bogusky, Michael J; Celikay, Recep W; Guare, James P; Newton, Randall C

    2016-01-01

    Ceramides are a central unit of all sphingolipids which have been identified as sites of biological recognition on cellular membranes mediating cell growth and differentiation. Several glycosphingolipids have been isolated, displaying immunomodulatory and anti-tumor activities. These molecules have generated considerable interest as potential vaccine adjuvants in humans. Accurate analyses of these and related sphingosine analogues are important for the characterization of structure, biological function, and metabolism. We report the complementary use of direct laser desorption ionization (DLDI), sheath flow electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and high-field nuclear magnetic resonance (NMR) analysis for the rapid, accurate identification of hexacosanoylceramide and starting materials. DLDI does not require stringent sample preparation and yields representative ions. Sheath-flow ESI yields ions of the product and byproducts and was significantly better than monospray ESI due to improved compound solubility. Negative ion sheath flow ESI provided data of starting materials and products all in one acquisition as hexacosanoic acid does not ionize efficiently when ceramides are present. NMR provided characterization of these lipid molecules complementing the results obtained from MS analyses. NMR data was able to differentiate straight chain versus branched chain alkyl groups not easily obtained from mass spectrometry. PMID:27367671

  1. Fourier Transform Mass Spectrometry and Nuclear Magnetic Resonance Analysis for the Rapid and Accurate Characterization of Hexacosanoylceramide

    PubMed Central

    Ross, Charles W.; Simonsick, William J.; Bogusky, Michael J.; Celikay, Recep W.; Guare, James P.; Newton, Randall C.

    2016-01-01

    Ceramides are a central unit of all sphingolipids which have been identified as sites of biological recognition on cellular membranes mediating cell growth and differentiation. Several glycosphingolipids have been isolated, displaying immunomodulatory and anti-tumor activities. These molecules have generated considerable interest as potential vaccine adjuvants in humans. Accurate analyses of these and related sphingosine analogues are important for the characterization of structure, biological function, and metabolism. We report the complementary use of direct laser desorption ionization (DLDI), sheath flow electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and high-field nuclear magnetic resonance (NMR) analysis for the rapid, accurate identification of hexacosanoylceramide and starting materials. DLDI does not require stringent sample preparation and yields representative ions. Sheath-flow ESI yields ions of the product and byproducts and was significantly better than monospray ESI due to improved compound solubility. Negative ion sheath flow ESI provided data of starting materials and products all in one acquisition as hexacosanoic acid does not ionize efficiently when ceramides are present. NMR provided characterization of these lipid molecules complementing the results obtained from MS analyses. NMR data was able to differentiate straight chain versus branched chain alkyl groups not easily obtained from mass spectrometry. PMID:27367671

  2. Characterization of a novel transcriptionally active domain in the transforming growth factor beta-regulated Smad3 protein.

    PubMed

    Prokova, Vassiliki; Mavridou, Sofia; Papakosta, Paraskevi; Kardassis, Dimitris

    2005-01-01

    Transforming growth factor beta (TGFbeta) regulates transcriptional responses via activation of cytoplasmic effector proteins termed Smads. Following their phosphorylation by the type I TGFbeta receptor, Smads form oligomers and translocate to the nucleus where they activate the transcription of TGFbeta target genes in cooperation with nuclear cofactors and coactivators. In the present study, we have undertaken a deletion analysis of human Smad3 protein in order to characterize domains that are essential for transcriptional activation in mammalian cells. With this analysis, we showed that Smad3 contains two domains with transcriptional activation function: the MH2 domain and a second middle domain that includes the linker region and the first two beta strands of the MH2 domain. Using a protein-protein interaction assay based on biotinylation in vivo, we were able to show that a Smad3 protein bearing an internal deletion in the middle transactivation domain is characterized by normal oligomerization and receptor activation properties. However, this mutant has reduced transactivation capacity on synthetic or natural promoters and is unable to interact physically and functionally with the histone acetyltransferase p/CAF. The loss of interaction with p/CAF or other coactivators could account, at least in part, for the reduced transactivation capacity of this Smad3 mutant. Our data support an essential role of the previously uncharacterized middle region of Smad3 for nuclear functions, such as transcriptional activation and interaction with coactivators. PMID:15994459

  3. Athabasca oil sands process water: characterization by atmospheric pressure photoionization and electrospray ionization fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Barrow, Mark P; Witt, Matthias; Headley, John V; Peru, Kerry M

    2010-05-01

    The Athabasca oil sands in Canada are a less conventional source of oil which have seen rapid development. There are concerns about the environmental impact, with particular respect to components in oil sands process water which may enter the aquatic ecosystem. Naphthenic acids have been previously targeted for study, due to their implications in toxicity toward aquatic wildlife, but it is believed that other components, too, contribute toward the potential toxicity of the oil sands process water. When mass spectrometry is used, it is necessary to use instrumentation with a high resolving power and mass accuracy when studying complex mixtures, but the technique has previously been hindered by the range of compounds that have been accessible via common ionization techniques, such as electrospray ionization. The research described here applied Fourier transform ion cyclotron resonance mass spectrometry in conjunction with electrospray ionization and atmospheric pressure photoionization, in both positive-ion and negative-ion modes, to the characterization of oil sands process water for the first time. The results highlight the need for broader characterization when investigating toxic components within oil sands process water. PMID:20359201

  4. Non-invasive monitoring of hemodynamic changes during hemodialysis by the use of a newly developed admittance cardiograph.

    PubMed

    Yoshii, Masayoshi; Minami, Junichi; Ishimitsu, Toshihiko; Yamakoshi, Ken-ichi; Matsuoka, Hiroaki

    2005-04-01

    Only a little information is available for the evaluation of the complex hemodynamic changes that occur during hemodialysis. Recently, we developed the transthoracic electrical admittance cardiograph for repeated measurements of cardiac output, and monitored hemodynamic changes during hemodialysis by the use of this device. We measured cardiovascular hemodynamic and autonomic parameters non-invasively during 210 min of hemodialysis in 19 chronic hemodialysis patients who for more than 2 months had no history of cardiovascular collapses during hemodialysis. Blood pressure was monitored every 10 min using a cuff-oscillometric device (TM-2425; A & D, Tokyo, Japan). Cardiac output was monitored on a beat-by-beat basis by a newly developed electrical admittance cardiograph (NICOVIEW PA1100; NEC, Tokyo, Japan). Electrocardiogram R-R intervals were also monitored by the TM-2425. Power spectral analysis of R-R intervals was performed to obtain the low-frequency (LF; 0.05-0.15 Hz) and the high-frequency (HF; 0.15-0.40 Hz) components based on an autoregressive model. Change in circulatory blood volume was also monitored by a CRIT-LINE (In-Line Diagnostics, Riverdale, UT, USA). Although blood volume declined significantly by 16.3 +/- 1.4% (mean +/- SE) during hemodialysis (P < 0.0001), mean blood pressure did not change significantly. Heart rate increased significantly from the initial values of 76.3 +/- 3.4-86.4 +/- 4.9 beats/min (P = 0.03). Cardiac output and stroke volume decreased significantly from 4.47 +/- 0.30 to 2.91 +/- 0.32 L/min (P < 0.0001), and from 57.0 +/- 3.7 to 33.9 +/- 3.1 mL (P < 0.0001), respectively. Total peripheral vascular resistance increased significantly from 1940 +/- 146 to 3117 +/- 280 dyne x s x cm(5) (P < 0.0001). The LF component did not show significant change, while the HF component decreased significantly (P = 0.007), and the LF/HF ratio increased significantly (P = 0.03). These results suggest that a reduction in parasympathetic nerve

  5. Bio-telemetric device for measurement of left ventricular pressure-volume loops using the admittance technique in conscious, ambulatory rats

    PubMed Central

    Raghavan, Karthik; Feldman, Marc D; Porterfield, John E; Larson, Erik R; Jenkins, J Travis; Escobedo, Daniel; Pearce, John A

    2011-01-01

    This paper presents the design, construction and testing of a device to measure pressure volume loops in the left ventricle of conscious, ambulatory rats. Pressure is measured with a standard sensor, but volume is derived from data collected from a tetrapolar electrode catheter using a novel admittance technique. There are two main advantages of the admittance technique to measure volume. First, the contribution from the adjacent muscle can be instantaneously removed. Second, the admittance technique incorporates the nonlinear relationship between the electric field generated by the catheter and the blood volume. A low power instrument weighing 27 g was designed, which takes pressure-volume loops every 2 minutes and runs for 24 hours. Pressure-volume data are transmitted wirelessly to a base station. The device was first validated in thirteen rats with an acute preparation with 2-D echocardiography used to measure true volume. From an accuracy standpoint, the admittance technique is superior to both the conductance technique calibrated with hypertonic saline injections, and calibrated with cuvettes. The device was then tested in six rats with a 24-hour chronic preparation. Stability of the animal preparation and careful calibration are important factors affecting the success of the device. PMID:21606560

  6. Physicochemical characterization of the thermal aging of insulating paper in power transformers

    SciTech Connect

    Lessard, M.C.; Van Nifterik, L.; Masse, M.; Penneau, J.F.; Grob, R.

    1996-12-31

    Paper is a low-cost base material with outstanding mechanical and electrical properties, which is why it is still a key element in the insulation of electrical apparatus. Under the effect of a variety of factors including temperature, paper can substantially lose its properties, thus jeopardizing the service life of costly equipment. To remedy this situation, new so-called thermally upgraded papers are being made by certain manufacturers. A study carried out jointly by Hydro-Quebec, Electricite de France and the Ecole Nationale Superieure de Chimie de Toulouse has allowed researchers to qualify the thermal resistance of three different types of thermostable paper. These papers have been selected as being representative of what is available on the market today. The paper samples were subjected to a thermal aging test in the presence of mineral oil to represent normal conditions of operation (150 C). The thermal degradation of the paper insulation is characterized by various physicochemical methods including measurement of the degree of polymerization, determination of 2-furfural in mineral oil by HPLC as well as determination of various sugars (monosaccharides, polysaccharides and anhydrosugars) in the paper using ion chromatography. This last method allows the authors to verify the formation of cellobiose, which is the real repeat unit of cellulose, as well as that of levoglucosan, which is an anhydrosugar and a precursor of 2-furfural. The evolution of all of these parameters, measured as a function of time, has allowed them to compare the thermal resistance of various insulating papers. The results of this study seem to show that, compared to traditional kraft paper, certain paper types are more susceptible to being thermally upgraded than others. This study also allowed the authors to demonstrate that the use of an inhibitor in mineral oil (DBPC) does not seem to influence the thermal degradation of these papers.

  7. Spectral Characterizations of the Clouds and the Earth's Radiant Energy System (CERES) Thermistor Bolometers using Fourier Transform Spectrometer (FTS) Techniques

    NASA Technical Reports Server (NTRS)

    Thornhill, K. Lee; Bitting, Herbert; Lee, Robert B., III; Paden, Jack; Pandey, Dhirendra K.; Priestley, Kory J.; Thomas, Susan; Wilson, Robert S.

    1998-01-01

    Fourier Transform Spectrometer (FTS) techniques are being used to characterize the relative spectral response, or sensitivity, of scanning thermistor bolometers in the infrared (IR) region (2 - >= 100-micrometers). The bolometers are being used in the Clouds and the Earth's Radiant Energy System (CERES) program. The CERES measurements are designed to provide precise, long term monitoring of the Earth's atmospheric radiation energy budget. The CERES instrument houses three bolometric radiometers, a total wavelength (0.3- >= 150-micrometers) sensor, a shortwave (0.3-5-micrometers) sensor, and an atmospheric window (8-12-micrometers) sensor. Accurate spectral characterization is necessary for determining filtered radiances for longwave radiometric calibrations. The CERES bolometers spectral response's are measured in the TRW FTS Vacuum Chamber Facility (FTS - VCF), which uses a FTS as the source and a cavity pyroelectric trap detector as the reference. The CERES bolometers and the cavity detector are contained in a vacuum chamber, while the FTS source is housed in a GN2 purged chamber. Due to the thermal time constant of the CERES bolometers, the FTS must be operated in a step mode. Data are acquired in 6 IR spectral bands covering the entire longwave IR region. In this paper, the TRW spectral calibration facility design and data measurement techniques are described. Two approaches are presented which convert the total channel FTS data into the final CERES spectral characterizations, producing the same calibration coefficients (within 0.1 percent). The resulting spectral response curves are shown, along with error sources in the two procedures. Finally, the impact of each spectral response curve on CERES data validation will be examined through analysis of filtered radiance values from various typical scene types.

  8. Secondary organic aerosol (trans)formation through aqueous phase guaiacol photonitration: chemical characterization of the products

    NASA Astrophysics Data System (ADS)

    Grgić, Irena; Kitanovski, Zoran; Kroflič, Ana; Čusak, Alen

    2014-05-01

    One of the largest primary sources of organic aerosol in the atmosphere is biomass burning (BB) (Laskin et al. 2009); in Europe its contribution to annual mean of PM10 is between 3 and 14 % (Maenhaut et al. 2012). During the process of wood burning many different products are formed via thermal degradation of wood lignin. Hardwood burning produces mainly syringol (2,6-dimetoxyphenol) derivatives, while softwood burning exclusively guaiacol (2-methoxyphenol) and its derivatives. Taking into account physical properties of methoxyphenols only, their concentrations in atmospheric waters might be underestimated. So, their aqueous phase reactions can be an additional source of SOA, especially in regions under significant influence of wood combustion. An important class of compounds formed during physical and chemical aging of the primary BBA in the atmosphere is nitrocatechols, known as strong absorbers of UV and Vis light (Claeys et al. 2012). Very recently, methyl-nitrocatechols were proposed as suitable markers for highly oxidized secondary BBA (Iinuma et al. 2010, Kitanovski et al. 2012). In the present work, the formation of SOA through aqueous phase photooxidation and nitration of guaiacol was examined. The key objective was to chemically characterize the main low-volatility products and further to check their possible presence in the urban atmospheric aerosols. The aqueous phase reactions were performed in a thermostated reactor under simulated sunlight in the presence of H2O2 and nitrite. Guaiacol reaction products were first concentrated by solid-phase extraction (SPE) and then subjected to semi-preparative liquid chromatography.The main product compounds were fractionated and isolated as pure solids and their structure was further elucidated by using nuclear magnetic resonance spectroscopy (1H, 13C and 2D NMR) and direct infusion negative ion electro-spray ionization tandem mass spectrometry (( )ESI-MS/MS). The main photonitration products of guaiacol (4

  9. Synthesis and characterization of catalysts for the selective transformation of biomass-derived materials

    NASA Astrophysics Data System (ADS)

    Ghampson, Isaac Tyrone

    The experimental work in this thesis focuses on generating catalysts for two intermediate processes related to the thermal conversion of lignocellulosic biomass: the synthesis and characterization of mesoporous silica supported cobalt catalysts for the Fischer-Tropsch reaction, and an exploration of the reactivity of bulk and supported molybdenum-based nitride catalysts for the hydrodeoxygenation (HDO) of guaiacol, a lignin model compound. The first section of the work details the synthesis of a series of silica-supported cobalt Fischer-Tropsch catalysts with pore diameters ranging from 2-23 nm. Detailed X-ray diffraction measurements were used to determine the composition and particle diameters of the metal fraction, analyzed as a three-phase system containing Cofcc, Cohcp and CoO particles. Catalyst properties were determined at three stages in catalyst history: (1) after the initial calcination step to thermally decompose the catalyst precursor into Co3O4, (2) after the hydrogen reduction step to activate the catalyst to Co and (3) after the FT reaction. From the study, it was observed that larger pore diameters supported higher turnover frequency; smaller pore diameters yielded larger mole fraction of CoO; XRD on post-reduction and post-FTS catalyst samples indicated significant changes in dispersivity after reduction. In the next section, the catalytic behaviors of unsupported, activated carbon-, alumina-, and SBA-15 mesoporous silica-supported molybdenum nitride catalysts were evaluated for the hydrodeoxygenation of guaiacol (2-methoxy phenol) at 300°C and 5 MPa. The nitride catalysts were prepared by thermal decomposition of bulk and supported ammonium heptamolybdate to form MoO 3 followed by nitridation in either flowing ammonia or a nitrogen/hydrogen mixture. The catalytic properties were strongly affected by the nitriding and purging treatment as well as the physical and chemical properties of support. The overall reaction was influenced by the

  10. Fibre optic sensors for load-displacement measurements and comparisons to piezo sensor based electromechanical admittance signatures

    NASA Astrophysics Data System (ADS)

    Maheshwari, Muneesh; Annamdas, Venu Gopal Madhav; Pang, John H. L.; Tjin, Swee Chuan; Asundi, Anand

    2015-04-01

    Structural health monitoring techniques using smart materials are on rise to meet the ever ending demand due to increased construction and manufacturing activities worldwide. The civil-structural components such as slabs, beams and columns and aero-components such as wings are constantly subjected to some or the other forms of external loading. This article thus focuses on condition monitoring due to loading/unloading cycle for a simply supported aluminum beam using multiple smart materials. On the specimen, fibre optic polarimetric sensor (FOPS) and fibre Bragg grating (FBG) sensors were glued. Piezoelectric wafer active sensor (PWAS) was also bonded at the centre of the specimen. FOPS and FBG provided the global and local strain measurements respectively whereas, PWAS predicted boundary condition variations by electromechanical admittance signatures. Thus these multiple smart materials together successfully assessed the condition of structure for loading and unloading tests.

  11. Purification and Characterization of Catechol 1,2-Dioxygenase from Acinetobacter sp. Y64 Strain and Escherichia coli Transformants.

    PubMed

    Lin, J; Milase, R N

    2015-12-01

    This study intends to purify and characterize catechol 1,2-dioxygenase (C1,2O) of phenol-degrading Acinetobacter sp. Y64 and of E. coli transformant. Acinetobacter sp. Y64 was capable of degrading 1000 mg/L of phenol within 14 ± 2 h at 30 °C, 160 rpm and pH of 7. One C1,2O of 36 kDa was purified using ammonium sulphate precipitation and Hitrap QFF column chromatograph with 49% recovery and a 10.6-fold increase in purity. Purified Y64 C1,2O had temperature and pH optimum at 37 °C and pH 7.7 respectively with the Michaelis constant of 17.53 µM and the maximal velocity of 1.95 U/mg, respectively. The presence of Fe(3+) or Fe(2+) enhanced the activity of Y64 C1,2O while other compounds such as Ca(2+), and EDTA had an inhibitory effect. 80% of C1,2O activity remained using 4-nitrocatechol as substrate while 2% remained using 3-methylcatechol compared with that using catechol. Y64 catA gene encoding C1,2O was amplified using PCR cloned into pET22b vector and expressed in Escherichia coli BL21 DE3 (pLysS) after transformation. Purified and cloned Y64 C1,2O show no significant differences in the biochemical properties. The phylogenetic tree based on the protein sequences indicates that these C1,2Os possess a common ancestry. PMID:26563518

  12. Comprehensive characterization of natural organic matter by MALDI- and ESI-Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Cao, Dong; Huang, Huogao; Hu, Ming; Cui, Lin; Geng, Fanglan; Rao, Ziyu; Niu, Hongyun; Cai, Yaqi; Kang, Yuehui

    2015-03-25

    Natural organic matter (NOM) is a complex and non-uniform mixture of organic compounds which plays an important role in environmental processes. Due to the complexity, it is challenging to obtain fully detailed structural information about NOM. Although Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) has been demonstrated to be a powerful tool for providing molecular information about NOM, multiple ionization methods are needed for comprehensive characterization of NOM at the molecular level considering the ionizing selectivity of different ionization methods. This paper reports the first use of matrix assisted laser desorption/ionization (MALDI) method coupled with FT-ICR-MS for molecular characterization of NOM within a mass range of 200-800 Da. The mass spectral data obtained by MALDI were systematically compared with data generated by electrospray ionization (ESI). It showed that complementary molecular information about NOM which could not be detected by ESI, were provided by MALDI. More unsaturated and aromatic constituents of NOM with lower O/C ratio (O/C ratio<0.5) were preferentially ionized in MALDI negative mode, whereas more polar constituents of NOM with higher O/C ratio were preferentially ionized in ESI negative mode. Molecular anions of NOM appearing at even m/z in MALDI negative ion mode were detected. The results show that NOM molecules with aromatic structures, moderate O/C ratio (0.7>O/C ratio>0.25) and lower H/C ratio were liable to form molecular anions at even m/z, whereas those with higher H/C ratio are more likely to form deprotonated ions at odd m/z. It is speculated that almost half of the NOM molecules identified by MALDI may be aromatic or condensed aromatic compounds with special groups which are liable to absorb electron from other molecules to generate free radical anions during MALDI ionization. PMID:25732692

  13. Characterization of the basidiomycetes Thelephora ganbajun Zang and Termitomyces albuminosus (Berk.) Heim by Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Liu, Gang; Song, Dingshan; Liu, Jian-hong; Zhao, Dezhang; Zhou, Yilan; Ou, Jiaming; Sun, Shizhong

    2006-09-01

    The basidiomycetes Thelephora ganbajun Zang and Termitomyces albuminosus (Berk.) Heim are two of the most favorite edible mushrooms in Yunnan Province, Southwest of China. In this paper, Fourier transform infrared speciroseopy (FTIR) was used to characterize the fruiting bodies of the two wild growing edible mushrooms. The results show that each mushroom has its characteristic infrared spectrum, in which the major peaks are attributed to proteins and polysaccharides. The spectra indicate that the poiysaccharides of the two mushrooms contain, both. α- and β-glycosidic linkage. A characteristic band of Thelephora ganbajun is an obvious band at about 1763 cm -1, which indicates that the mushroom contain oil. Differences are observed in the spectra of different parts of the fruiting body of Termitomyces albuminosus. According to the differences of the characteristic spectra peaks and absorbance ratios, the different parts of mushroom can be discriminated. The results suggest that the different species of mushrooms might be identified by the vibrational spectral features of the different parts of the fruiting bodies of mushrooms.

  14. High Fuel Utilization in Solid Oxide Fuel Cells: Experimental Characterization and Data Analysis with Continuous Wavelet Transform

    NASA Astrophysics Data System (ADS)

    Esposito, Angelo; Russo, Luigi; Kändler, Christoph; Pianese, Cesare; Ludwig, Bastian; Steiner, Nadia Yousfi

    2016-06-01

    The on-line diagnostics of Solid Oxide Fuel Cells (SOFCs) is a critical tool to achieve optimal performance and extend the lifetime. The Continuous Wavelet Transform (CWT) methodology was applied to the SOFC voltage signal to detect signatures that reveal the presence of a fault in the cell/stack. The selected fault was anode re-oxidation caused by high Fuel Utilization (FU) (higher then nominal). To experimentally emulate the high FU faults, a standard test procedure was developed, which was used to characterize a μ-CHP system at high FU operation. To complete the analysis, data collected on Single Cells were exploited too. The CWT was applied to the voltage signal for each FU level to verify the qualitative difference (signature) between the signals at different FU's within the same tests as well as the correspondence between the same conditions over different tests. A statistical study was performed to quantify the observed differences and to determine the correspondence between CWT coefficients and operating conditions. The approach proves to be suitable to diagnose high FU in SOFC, showing a successful detection rate above 76%. The results show the good potential of using the CWT methodology as diagnostic tools for SOFCs from cell to stack level.

  15. Characterization of near-terahertz complementary metal-oxide semiconductor circuits using a Fourier-transform interferometer

    DOE PAGESBeta

    Arenas, D. J.; Shim, Dongha; Koukis, D. I.; Seok, Eunyoung; Tanner, D. B.; O, Kenneth K.

    2011-10-24

    Optical methods for measuring of the emission spectra of oscillator circuits operating in the 400-600 GHz range are described. The emitted power from patch antennas included in the circuits is measured by placing the circuit in the source chamber of a Fourier-transform interferometric spectrometer. The results show that this optical technique is useful for measuring circuits pushing the frontier in operating frequency. The technique also allows the characterization of the circuit by measuring the power radiated in the fundamental and in the harmonics. This capability is useful for oscillator architectures designed to cancel the fundamental and use higher harmonics. Themore » radiated power was measured using two techniques: direct measurement of the power by placing the device in front of a bolometer of known responsivity, and by comparison to the estimated power from blackbody sources. The latter technique showed that these circuits have higher emission than blackbody sources at the operating frequencies, and, therefore, offer potential spectroscopy applications.« less

  16. Spatiotemporal characterization of land subsidence and uplift in Phoenix using InSAR time series and wavelet transforms

    NASA Astrophysics Data System (ADS)

    Miller, Megan Marie; Shirzaei, Manoochehr

    2015-08-01

    The effects of land subsidence pose a significant hazard to the environment and infrastructure in the arid, alluvial basins of Phoenix, Arizona. Improving our understanding of the source and mechanisms of subsidence is important for planning and risk management. Here we employ multitemporal interferometric analysis of large synthetic aperture radar data sets acquired by ERS and Envisat satellites to investigate ground deformation. The ERS data sets from 1992 to 1996 and Envisat, 2003-2010, are used to generate line of sight (LOS) time series and velocities in both the ascending and descending tracks. The general deformation pattern is consistent among data sets and is characterized by three zones of subsidence and a broad zone of uplift. The multitrack Envisat LOS time series of surface deformation are inverted to obtain spatiotemporal maps of the vertical and horizontal deformation fields. We use observation wells to provide an in situ, independent data set of hydraulic head levels. Then we analyze vertical interferometric synthetic aperture radar and hydraulic head level time series using continuous wavelet transform to separate periodic signal components and the long-term trend. The isolated signal components are used to estimate the elastic storage coefficient, the inelastic skeletal storage coefficient, and compaction time constants. Together these parameters describe the storage response of an aquifer system to changes in hydraulic head and surface elevation. Understanding aquifer parameters is useful for the ongoing management of groundwater resources.

  17. Transformer winding defects identification based on a high frequency method

    NASA Astrophysics Data System (ADS)

    Florkowski, Marek; Furgał, Jakub

    2007-09-01

    The transformer diagnostic methods are systematically being improved and extended due to growing requirements for reliability of power systems in terms of uninterrupted power supply and avoidance of blackouts. Those methods are also driven by longer lifetime of transformers and demand for reduction of transmission and distribution costs. Hence, the detection of winding faults in transformers, both in exploitation or during transportation is an important aspect of power transformer failure prevention. The frequency response analysis method (FRA), more and more frequently used in electric power engineering, has been applied for investigations and signature analysis based on the admittance and transfer function. The paper presents a novel approach to the identification of typical transformer winding problems such as axial or radial movements or turn-to-turn faults. The proposed transfer function discrimination (TFD) criteria are based on the derived transfer function ratios, manifesting higher sensitivity.

  18. Development and application of Fourier transform infrared spectroscopic techniques to the characterization of coal and oil shale

    SciTech Connect

    Snyder, R.W.

    1982-01-01

    The development of application programs for infrared spectroscopy has been an ongoing proposition for a number of years. This development, however, was accelerated with the advent of Fourier transform infared (FT-IR) instruments and their built-in mini-computers. The uses and pitfalls of several of these routines are discussed in this thesis. A least-squares curve resolving program has been developed and the use of this program is also discussed. The analysis of complex, multicomponent polymeric materials, such as coal and oil shale, by conventional infrared spectroscopy has been a difficult problem. The use of FT-IR spectroscopy for the qualitative and quantitative analysis of these types of materials is discussed. A characterization of oil shale from the Mahogany Zone of the Green River Formation has been obtained by FT-IR. A quantitative analysis of the mineral component by FT-IR spectroscopy is shown to be comparable to that obtained by x-ray diffraction when considering broad mineral types, i.e., carbonates. Methods for the FT-IR analysis of the organic component, both from the whole shale and from kerogen specimens, have been refined. There is a good correlation between the intensity of alkyl bands and Fisher assay yields. An assessment is made of the applicability of extinction coefficients obtained from paraffins to their use in quantitative analysis in oil shales. A quantitative analysis of OH content in coal by FT-IR is comparable to that done by other methods (i.e., chemical and NMR). An analysis is also made of the various types of OH groups in coal.

  19. Satellite Characterization of Biomass Burning: Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope Study of Combustion Experiments

    NASA Astrophysics Data System (ADS)

    Padilla, D.; Steiner, J. C.

    2005-12-01

    Fourier Transform Infrared (FTIR) examination of the combustion products of selected forest materials using a meeker burner flame at temperatures up to 500 degrees Celsius produces a cluster of broad distinct peaks throughout the 400 to 4000 cm-1 wavenumber interval. Distinct bands bracketed by wavenumbers 400-700, 1500-1700, 2200-2400 and 3300-3600 cm-1 show variable intensity with an average difference between the least absorbing and most strongly absorbing species of approximately fifty percent. Given that spectral band differences of ten percent are within the range of modern satellite spectrometers, these band differences are of potential value for discriminating between fires that are impacting a range of vegetation types. Corresponding scanning electron microscope and energy dispersive micro-chemical (SEM/ED) analysis establishes that the evolved soot particles exhibit a characteristic rounded morphology, are carbon rich and host a wide range of adsorbed elements, including calcium, aluminum, potassium, silicon, sulfur and trace nitrogen. Combustion experiments involving leaves and branches as a subset of the biomass experiments at 200-500 degrees Celsius yield a similar broad background, but with peak shifts for maxima residing at less than 1700 cm-1. Additional peaks appear in the ranges 1438-1444, 875 and 713 cm-1. These peak are of potential use for discriminating between hot and smoldering fires, and between soot and smoke yields from green woods and whole-wood or lumber. The spectral shifts noted for low temperature smoldering conditions are in the vicinity of those cited for green vegetation and may not be resolved by present satellite platforms. Nevertheless, the experimental peak data set is of potential use for discriminating between a conflagration or accentuated fire and one characterized by smoldering at low temperature. SEM/ED analysis of the combusted leaf, branch, bark and various crown assemblages yields comparable morphological and

  20. Characterization of Low Temperature Ferrite/Austenite Transformations in the Heat Affected Zone of 2205 Duplex Stainless Steel Arc Welds

    SciTech Connect

    Palmer, T A; Elmer, J W; Babu, S S; Vitek, J M

    2003-08-20

    Spatially Resolved X-Ray Diffraction (SRXRD) has been used to identify a previously unobserved low temperature ferrite ({delta})/austenite({gamma}) phase transformation in the heat affected zone (HAZ) of 2205 Duplex Stainless Steel (DSS) welds. In this ''ferrite dip'' transformation, the ferrite transforms to austenite during heating to peak temperatures on the order of 750 C, and re-transforms to ferrite during cooling, resulting in a ferrite volume fraction equivalent to that in the base metal. Time Resolved X-Ray Diffraction (TRXRD) and laser dilatometry measurements during Gleeble{reg_sign} thermal simulations are performed in order to verify the existence of this low temperature phase transformation. Thermodynamic and kinetic models for phase transformations, including both local-equilibrium and para-equilibrium diffusion controlled growth, show that diffusion of substitutional alloying elements does not provide a reasonable explanation for the experimental observations. On the other hand, the diffusion of interstitial alloying elements may be rapid enough to explain this behavior. Based on both the experimental and modeling results, two mechanisms for the ''ferrite dip'' transformation, including the formation and decomposition of secondary austenite and an athermal martensitic-type transformation of ferrite to austenite, are considered.

  1. Characterization of phase transformation during hot compressive deformation in a β-stabilized Ti–45Al–7Nb–0.4W–0.15B alloy

    SciTech Connect

    Liu, Bin; Liu, Yong Huang, Lan; Li, Huizhong; He, Yuehui

    2015-07-15

    A β-stabilized Ti–45Al–7Nb–0.4W–0.15B (at.%) alloy was hot deformed by uniaxial compression and the phase evolution during the compression was characterized with X-ray diffraction, scanning electron microscopy and electron probe microanalysis. The results show that modest deformation stress during hot compression restrains the γ → α transformation and the decomposition of β phase. The restrained γ → α transformation is a result of a modified equilibrium of the γ and α phases due to the applied stress, and the restrained β decomposition is a kinetic effect due to the decelerated diffusion of β-stabilizing elements caused by the compressive stress. - Highlights: • In β-stabilized TiAl alloys, hot deformation has great influence on the equilibrium of the γ, α, and β phases. • Deformation restrains the γ → α transformation. • Deformation inhibits the decomposition of the β phase.

  2. Modeling and analysis of the admittance characteristics of n+ metal-oxide-semiconductor capacitors with oxide and interface states - Gd0.25Ga0.15O0.6/Ga2O3 on In0.53Ga0.47As

    NASA Astrophysics Data System (ADS)

    Paterson, G. W.; Holland, M. C.; Thayne, I. G.; Long, A. R.

    2012-04-01

    The 300-K admittance characteristics of n+ In0.53Ga0.47As MOS capacitors with a dielectric stack of Gd0.25Ga0.15O0.6/Ga2O3 in as-grown condition are examined in detail and compared to an oxide trap model that we previously introduced. The model explains many of the observed features not contained in the interface state model. By fitting the model to experimental data, we extract a distribution of defect states in space and energy within the oxide and at the oxide/semiconductor interface separately. Oxide states are the dominant defects over a wide range of energy. The defect state densities are not subject to the usual resolution limits of conventional analyses. Using this approach, it is possible to characterize relatively rapidly a wide range of energies at a single temperature without the need for reaching the low or high limits of frequency. The implications for the conventional interface state density (Dit) extraction techniques are explored. It is shown how oxide states can affect the extraction of sample parameters, particularly the insulator capacitance, and can result in a range of extracted Dit values. We believe these contribute to the wide range of Dit reported in the literature from similar admittance characteristics of a number of oxides on In0.53Ga0.47As.

  3. Performance analysis of a plasmonic sensor based on gold nanoparticle film in infrared light using the admittance loci method

    NASA Astrophysics Data System (ADS)

    Brahmachari, Kaushik; Ray, Mina

    2015-02-01

    A theoretical design of surface plasmon resonance (SPR) structure operating in attenuated total reflection (ATR) mode and comprising of silicon or chalcogenide (2S2G) prism material coated with gold film having different nanoparticle sizes has been reported along with some interesting performance related simulation results at the operating wavelength of 1200 nm in infrared. The admittance loci based technique has been employed for the appropriate choice of the metal layer thickness. The sensitivity and other performance parameters of the structure based on the choice of the high index prism material and correct gold nanoparticle size have also been presented. In comparison to other conventional prism based plasmonic structures, the proposed model provides the extra degree of freedom, i.e., variations of nanoparticle size in addition to the variation in layer thickness and the use of different high index prism materials like silicon, 2S2G materials, etc. Moreover, the width of the SPR curve can be controlled by using different high index prism materials as well as by changing gold nanoparticle size. Higher sensitivity can be achieved with 2S2G while higher detection accuracy is provided by silicon as prism material.

  4. LOPES II--Design and Evaluation of an Admittance Controlled Gait Training Robot With Shadow-Leg Approach.

    PubMed

    Meuleman, Jos; van Asseldonk, Edwin; van Oort, Gijs; Rietman, Hans; van der Kooij, Herman

    2016-03-01

    Robotic gait training is gaining ground in rehabilitation. Room for improvement lies in reducing donning and doffing time, making training more task specific and facilitating active balance control, and by allowing movement in more degrees of freedom. Our goal was to design and evaluate a robot that incorporates these improvements. LOPES II uses an end-effector approach with parallel actuation and a minimum amount of clamps. LOPES II has eight powered degrees of freedom (hip flexion/extension, hip abduction/adduction, knee flexion/extension, pelvis forward/aft and pelvis mediolateral). All other degrees of freedom can be left free and pelvis frontal- and transversal rotation can be constrained. Furthermore arm swing is unhindered. The end-effector approach eliminates the need for exact alignment, which results in a donning time of 10-14 min for first-time training and 5-8 min for recurring training. LOPES II is admittance controlled, which allows for the control over the complete spectrum from low to high impedance. When the powered degrees of freedom are set to minimal impedance, walking in the device resembles free walking, which is an important requisite to allow task-specific training. We demonstrated that LOPES II can provide sufficient support to let severely affected patients walk and that we can provide selective support to impaired aspects of gait of mildly affected patients. PMID:26731771

  5. Damage monitoring using fiber optic sensors and by analysing electro-mechanical admittance signatures obtained from piezo sensor

    NASA Astrophysics Data System (ADS)

    Maheshwari, Muneesh; Annamdas, Venu Gopal M.; Pang, John Hock Lye; Tjin, Swee C.; Asundi, Anand

    2015-12-01

    Damage monitoring is the need of the hour in this age of infrastructure. Many methods are being used for damage monitoring in different mechanical and civil structures. Some of them are strain based methods in which abruptly increased strain signifies the presence of damage in the structure. This article focuses on crack monitoring of a fixedfixed beam using fiber optic sensors which can measure strain locally or globally. The two types of fiber optic sensors used in this research are fiber Bragg grating (FBG) and fiber optic polarimetric sensors (FOPS). FBG and FOPS are used for local strain monitoring (at one point only) and global strain monitoring (in the entire specimen) respectively. At the centre of the specimen, a piezoelectric wafer active sensor (PWAS) is also attached. PWAS is used to obtain electromechanical admittance (EMA) signatures. Further, these EMA signatures are analysed to access the damage state in the beam. These multiple smart materials together provide improved information on damages in the specimen which is very valuable for the structural health monitoring (SHM) of the specimen.

  6. Ear-canal acoustic admittance and reflectance effects in human neonates. I. Predictions of otoacoustic emission and auditory brainstem responses

    NASA Astrophysics Data System (ADS)

    Keefe, Douglas H.; Zhao, Fei; Neely, Stephen T.; Gorga, Michael P.; Vohr, Betty R.

    2003-01-01

    This report describes the extent to which ear-canal acoustic admittance and energy reflectance (YR) in human neonates (1) predict otoacoustic emission (OAE) levels and auditory brainstem response (ABR) latencies, and (2) classify OAE and ABR responses as present or absent. Analyses are reported on a subset of ears in which hearing screening measurements were obtained previously [Norton et al., Ear. Hear. 21, 348-356 (2000a)]. Tests on 1405 ears included YR, distortion-product OAEs, transient-evoked OAEs, and ABR. Principal components analysis reduced the 33 YR variables to 5-7 factors. OAE levels decreased and ABR latencies increased with increasing high-frequency energy reflectance. Up to 28% of the variance in OAE levels and 12% of the variance in ABR wave-V latencies were explained by these factors. Thus, the YR response indirectly encodes information on inter-ear variations in forward and reverse middle-ear transmission. The YR factors classify OAEs with an area under the relative operating characteristic (ROC) curve as high as 0.79, suggesting that middle-ear dysfunction is partly responsible for the inability to record OAEs in some ears. The YR factors classified ABR responses less well, with ROC areas of 0.64 for predicting wave-V latency and 0.56 for predicting Fsp.

  7. An admittance study of the Reykjanes Ridge and elevated plateaux between the Charlie-Gibbs and Senja fracture zones

    NASA Astrophysics Data System (ADS)

    Heller, Daniel A.; Marquart, Gabriele

    2002-01-01

    The North Atlantic between the Charlie-Gibbs and Senja Fracture Zones shows a number of oceanic plateaux, continental fragments and unusual mid-oceanic ridges, the Reykjanes Ridges and the Iceland Plateau being the most prominent ones. While rifted continental fragments and marginal volcanic plateaux have been formed during the initial formation process of the North Atlantic, others, such as the Reykjanes Ridge and plume-related plateaux such as Iceland and possibly also Jan Mayen, are still under development. By studying the ratio of geoid to topography in the long-wavelength range for these regions of elevated topography and comparing the results with theoretical models of crustal loading and subsurface thermal uplift we can show that the Rockall Bank and the Vøring Plateau are compensated by a thick crust alone, while the Iceland Plateau, the outer Faeroe Plateau and the Jan Mayen Block have a strong component of deeply situated mass anomalies. The admittance, the spectral ratio of geoid to topography, for a number of profiles across the Reykjanes Ridge clearly indicates a decrease in compensation depth with distance from Iceland. This strengthens the argument for a mass flux from the Iceland Plume into the Reykjanes Ridge.

  8. Identification and characterization of salmonella serotypes using DNA spectral characteristics by fourier transform infrared (FT-IR) spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Analysis of DNA samples of Salmonella serotypes (Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky) were performed using Fourier transform infrared spectroscopy (FT-IR) spectrometer by placing directly in contact with a diamond attenua...

  9. Characterization of the chemical composition of soil humic acids using Fourier transform ion cyclotron resonance mass spectrometry

    NASA Astrophysics Data System (ADS)

    Ikeya, Kosuke; Sleighter, Rachel L.; Hatcher, Patrick G.; Watanabe, Akira

    2015-03-01

    The composition of humic acids (HAs) with varying degrees of humification isolated from 10 common Japanese soils was characterized using negative ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry at 12 T. In particular, attention was paid to polynuclear aromatic components, which are more associated with the refractory nature of HAs and their resistance to biodegradation in soil than single C ring aromatic entities, such as lignin-like components, and aliphatic functionalities. Thousands of peaks were observed in the m/z range of 200-700, and molecular formulas were assigned to 817-2457 peaks in each sample. The molecular formulas having H/C and O/C ratios similar to those of lipid, protein, and other aliphatics with low double bond equivalents (DBE) of 0-7 were generally observed across the m/z range of 200-700. Although there were a number of molecular formulas having H/C and O/C values similar to those of lignin across the wide m/z range in the HAs with a low degree of humification, most lignin-like molecular formulas in the larger m/z range (450-650) or irrespective of m/z were lacking in the HAs with middle and high degrees of humification, respectively. These observations suggest a longer residence time for lignin monomers/dimers (and their derivatives; m/z 200-400) than larger lignin oligomers (m/z 450-650) in HA structural domains. The number of molecular formulas having H/C and O/C values similar to condensed aromatics increased with increasing degree of humification. The m/z and DBE values of condensed aromatic-like molecular formulas in the HAs with a lower degree of humification were <500 and 10-25, respectively, whilst the ranges expanded to 600 and 30-33, respectively, in the highly-humified black HAs. Kendrick mass defect analysis using a carboxyl group as the characteristic functional group found that 31, 73, and 39 molecular formulas had chain-type, net-type, and biphenyl-type condensed aromatic acids

  10. Characterization of human vascular smooth muscle cells transformed by the early genetic region of SV40 virus.

    PubMed Central

    Legrand, A.; Greenspan, P.; Nagpal, M. L.; Nachtigal, S. A.; Nachtigal, M.

    1991-01-01

    Human arterial smooth muscle cells transfected with the plasmid pSV3-neo, which contains the SV40 virus early region and the neor gene, developed colonies of morphologically transformed cells. Five cell strains were initiated from these colonies and could be subcultivated for up to 9 months before entering a stage of crisis that ended their life span. Deoxyribonucleic acid (DNA) molecules containing viral sequences were found free and integrated in the transformed cells. The intranuclear SV40 large T antigen and the p53 cellular protein were expressed in the transformed cells. Most of the transformed cells were spindle shaped but some were large and multinucleated. The modal chromosome numbers were in the triploid range, and aberrations, particularly dicentrics, were common. The transcripts for smooth muscle actins were significantly reduced and there were less alpha-actin filaments detected by immunofluorescence. Cytochemical staining disclosed a large accumulation of lipid droplets in the transformed cells incubated with rabbit hypercholesterolemic beta-very-low-density lipoprotein. Chemical analysis showed that cholesteryl esters were significantly elevated in these cells. Phenotypic changes induced in human vascular smooth muscle cells by SV40 early genes are similar to those found in smooth muscle cells from atherosclerotic lesions and may indicate common pathogenetic mechanisms. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:1653520

  11. Transformation and characterization of an arsenic gene operon from urease-positive thermophilic Campylobacter (UPTC) in Escherichia coli.

    PubMed

    Matsuda, M; Kuribayashi, T; Yamamoto, S; Millar, B C; Moore, J E

    2016-01-01

    An arsenate susceptibility test was performed with transformed and cultured Escherichia coli DH5α cells, which carried recombinant DNA of full-length arsenic (ars) operon, namely a putative membrane permease, ArsP; a transcriptional repressor, ArsR; an arsenate reductase, ArsC; and an arsenical-resistance membrane transporter, Acr3, from the Japanese urease-positive thermophilic Campylobacter lari (UPTC) CF89-12. The E. coli DH5α transformant showed reduced susceptibility to arsenate (~1536 μg/mL), compared to the control. Thus, these ars four-genes from the UPTC CF89-12 strain cells could confer a reduced susceptibility to arsenate in the transformed and E. coli DH5α cells. E. coli transformants with truncated ars operons, acr3 (acr3) and arsC-acr3 (∆arsC-acr3), of the ars operon, showed an MIC value of 384 μg/mL (~384 μg/mL), similar to the E. coli cells which carried the pGEM-T vector (control). Reverse transcription PCR confirmed in vivo transcription of recombinant full-length ars operon and deletion variants (∆acr3 and ∆arsC-acr3) in the transformed E. coli cells. PMID:26122364

  12. Chemical morphology of Areca nut characterized directly by Fourier transform near-infrared and mid-infrared microspectroscopic imaging in reflection modes.

    PubMed

    Chen, Jian-Bo; Sun, Su-Qin; Zhou, Qun

    2016-12-01

    Fourier transform near-infrared (NIR) and mid-infrared (MIR) imaging techniques are essential tools to characterize the chemical morphology of plant. The transmission imaging mode is mostly used to obtain easy-to-interpret spectra with high signal-to-noise ratio. However, the native chemical compositions and physical structures of plant samples may be altered when they are microtomed for the transmission tests. For the direct characterization of thick plant samples, the combination of the reflection NIR imaging and the attenuated total reflection (ATR) MIR imaging is proposed in this research. First, the reflection NIR imaging method can explore the whole sample quickly to find out typical regions in small sizes. Next, each small typical region can be measured by the ATR-MIR imaging method to reveal the molecular structures and spatial distributions of compounds of interest. As an example, the chemical morphology of Areca nut section is characterized directly by the above approach. PMID:27374557

  13. Generation and characterization of soybean and marker-free tobacco plastid transformants over-expressing a bacterial 4-hydroxyphenylpyruvate dioxygenase which provides strong herbicide tolerance.

    PubMed

    Dufourmantel, Nathalie; Dubald, Manuel; Matringe, Michel; Canard, Hélène; Garcon, Frédéric; Job, Claudette; Kay, Elisabeth; Wisniewski, Jean-Pierre; Ferullo, Jean-Marc; Pelissier, Bernard; Sailland, Alain; Tissot, Ghislaine

    2007-01-01

    Plant 4-hydroxyphenylpyruvate dioxygenase (HPPD) is part of the biosynthetic pathway leading to plastoquinone and vitamin E. This enzyme is also the molecular target of various new bleaching herbicides for which genetically engineered tolerant crops are being developed. We have expressed a sensitive bacterial hppd gene from Pseudomonas fluorescens in plastid transformants of tobacco and soybean and characterized in detail the recombinant lines. HPPD accumulates to approximately 5% of total soluble protein in transgenic chloroplasts of both species. As a result, the soybean and tobacco plastid transformants acquire a strong herbicide tolerance, performing better than nuclear transformants. In contrast, the over-expression of HPPD has no significant impact on the vitamin E content of leaves or seeds, quantitatively or qualitatively. A new strategy is presented and exemplified in tobacco which allows the rapid generation of antibiotic marker-free plastid transformants containing the herbicide tolerance gene only. This work reports, for the first time, the plastome engineering for herbicide tolerance in a major agronomic crop, and a technology leading to marker-free lines for this trait. PMID:17207262

  14. Photolytic and photocatalytic transformation of methadone in aqueous solutions under solar irradiation: kinetics, characterization of major intermediate products and toxicity evaluation.

    PubMed

    Postigo, Cristina; Sirtori, Carla; Oller, Isabel; Malato, Sixto; Maldonado, Manuel Ignacio; López de Alda, Miren; Barceló, Damià

    2011-10-15

    The present manuscript describes the transformation and mineralization of methadone (MET) in aqueous solutions (demineralized water (DW) and synthetic municipal wastewater effluent (SWeff)) by natural solar irradiation and two solar photocatalytic processes: heterogeneous photocatalysis with titanium dioxide (TiO2) and homogeneous photocatalysis by photo-Fenton. Direct solar irradiation resulted in almost complete transformation of MET in the investigated matrices after 20 h of normalized irradiation time. MET photocatalytic transformation required shorter illumination times in DW compared to SWeff. Only 16 and 36 min of solar illumination were required during photo-Fenton and photocatalysis with TiO2, respectively, to transform MET completely in SWeff. Mineralization of the dissolved organic carbon took place only during photocatalytic treatments. Kinetics parameters were calculated for processes comparison. Additionally, phototransformation intermediates generated during each treatment were investigated and characterized by means of ultra-performance liquid chromatography coupled to quadrupole-time of flight tandem mass spectrometry (UPLC-QqTOF-MS/MS). The main MET phototransformation pathways were observed to be hydroxylation, and fragmentation and cyclization. According to the Vibrio fischeri bioassay, the acute toxicity of the generated phototransformation products was not relevant, since the observed inhibition percentages of bacterial bioluminescence were always below 30% after 30 min of sample contact. PMID:21767861

  15. A systems level characterization and tradespace evaluation of a simulated airborne Fourier transform infrared spectrometer for gas detection

    NASA Astrophysics Data System (ADS)

    Weiner, Aaron

    The remote sensing gas detection problem is one with no straightforward solution. While success has been achieved in detecting and identifying gases released from industrial stacks and other large plumes, the fugitive gas detection problem is far more complex. Fugitive gas represents a far smaller target and may be generated by leaking pipes, vents, or small scale chemical production. The nature of fugitive gas emission is such that one has no foreknowledge of the location, quantity, or transient rate of the targeted effluent which requires one to cover a broad area with high sensitivity. In such a scenario, a mobile airborne platform would be a likely candidate. Further, the spectrometer used for gas detection should be capable of rapid scan rates to prevent spatial and spectral smearing, while maintaining high resolution to aid in species identification. Often, insufficient signal to noise (SNR) prevents spectrometers from delivering useful results under such conditions. While common dispersive element spectrometers (DES) suffer from decreasing SNR with increasing spectral dispersion, Fourier Transform Spectrometers (FTS) generally do not and would seemingly be an ideal choice for such an application. FTS are ubiquitous in chemical laboratories and in use as ground based spectrometers, but have not become as pervasive in mobile applications. While FTS spectrometers would otherwise be ideal for high resolution rapid scanning in search of gaseous effluents, when conducted via a mobile platform the process of optical interferogram formation to form spectra is corrupted when the input signal is temporally unstable. This work seeks to explore the tradespace of an airborne Michelson based FTS in terms of modeling and characterizing the performance degradation over a variety of environmental and optical parameters. The major variables modeled and examined include: maximum optical path distance (resolution), scan rate, platform velocity, altitude, atmospheric and

  16. Numerical calculations for effects of structure of skeletal muscle on frequency-dependence of its electrical admittance and impedance

    NASA Astrophysics Data System (ADS)

    Sekine, Katsuhisa; Yamada, Ayumi; Kageyama, Hitomi; Igarashi, Takahiro; Yamamoto, Nana; Asami, Koji

    2015-06-01

    Numerical calculations were carried out by the finite difference method using three-dimensional models to examine effects of the structure of skeletal muscle on the frequency-dependence of its electrical admittance Y and impedance Z in transversal and longitudinal directions. In the models, the muscle cell was represented by a rectangular solid surrounded by a smooth surface membrane, and the cells were assumed to be distributed periodically. The width of the cross section of the cell, thickness of the intercellular medium, and the relative permittivities and the conductivities of the cell interior, the intercellular medium and the surface membrane were changed. Based on the results of the calculations, reported changes in Y and Z of the muscles from 1 kHz to 1 MHz were analyzed. The analyses revealed that a decreased cell radius was reasonable to explain the Y and Z of the muscles of immature rats, rats subjected to sciatic nerve crush at chronic stage and the amyotrophic lateral sclerosis (ALS) mice. Changes in Y and Z due to the sciatic nerve crush at acute stage were attributable to the decreased cell radius, the increased space between the cells, the increased permittivity of the surface membrane and the increased conductivity of the cell interior. The changes in Z due to contraction were explained by the changes in the cell radius, and the conductivities of the cell interior and the intercellular medium. The changes in Z of meat due to aging were compared with the effects of the increase in the conductivity of the surface membrane.

  17. Diffuse-Reflectance Fourier-Transform Mid-Infrared Spectroscopy as a Method of Characterizing Changes in Soil Organic Matter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diffuse-Reflectance Fourier-Transform Mid-Infrared Spectroscopy (FTIR) can be used quickly and non destructively to identify and quantify the presence of important organic functional groups in environmental samples. However, soils contain myriad organic and inorganic components that absorb in the M...

  18. Diffuse-reflectance fourier-transform mid-infrared spectroscopy as a method of characterizing changes in soil organic matter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diffuse-Reflectance Fourier-Transform Mid-Infrared Spectroscopy (MidIR) can identify the presence of important organic functional groups in soil organic matter (SOM). Soils contain myriad organic and inorganic components that absorb in the MidIR so spectral interpretation needs to be validated in or...

  19. Hydration and energy dissipation measurements of biomolecules on a piezoelectric quartz oscillator by admittance analyses.

    PubMed

    Ozeki, Tomomitsu; Morita, Mizuki; Yoshimine, Hiroshi; Furusawa, Hiroyuki; Okahata, Yoshio

    2007-01-01

    , DNAs, and pullulans were relatively deviant toward the large hydration and energy dissipation from the theoretical line as perfect elastic materials, meaning that the large energy dissipation occurs because of viscoelastic properties of denatured proteins, linear DNAs, and pullulans in the water phase, in addition to energy dissipation due to the hydration of molecules. These two parameters could characterize various biomolecules with structural properties in aqueous solutions. PMID:17194124

  20. Characterization of Nanoscale Transformations in Polyelectrolyte Multilayers Fabricated from Plasmid DNA Using Laser Scanning Confocal Microscopy in Combination with Atomic Force Microscopy

    PubMed Central

    Fredin, Nathaniel J.; Flessner, Ryan M.; Jewell, Christopher M.; Bechler, Shane L.; Buck, Maren E.; Lynn, David M.

    2010-01-01

    Laser scanning confocal microscopy (LSCM) and atomic force microscopy (AFM) were used to characterize changes in nanoscale structure that occur when ultrathin polyelectrolyte multilayers (PEMs) are incubated in aqueous media. The PEMs investigated here were fabricated by the deposition of alternating layers of plasmid DNA and a hydrolytically degradable polyamine onto a precursor film composed of alternating layers of linear poly(ethylene imine) (LPEI) and sodium poly(styrene sulfonate) (SPS). Past studies of these materials in the context of gene delivery revealed transformations from a morphology that is smooth and uniform to one characterized by the formation of nanometer-scale particulate structures. We demonstrate that in-plane registration of LSCM and AFM images acquired from the same locations of films fabricated using fluorescently labeled polyelectrolytes allows the spatial distribution of individual polyelectrolyte species to be determined relative to the locations of topographic features that form during this transformation. Our results suggest that this physical transformation leads to a morphology consisting of a relatively less disturbed portion of film composed of polyamine and DNA juxtaposed over an array of particulate structures composed predominantly of LPEI and SPS. Characterization by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) microanalysis provides additional support for this interpretation. The combination of these different microscopy techniques provides insight into the structures and dynamics of these multicomponent thin films that cannot be achieved using any one method alone, and that could prove useful for the further development of these assemblies as platforms for the surface-mediated delivery of DNA. PMID:20155860

  1. Admittance-voltage profiling of AlxGa1-xN/GaN heterostructures: Frequency dependence of capacitance and conductance

    NASA Astrophysics Data System (ADS)

    Köhler, K.; Pletschen, W.; Godejohann, B.; Müller, S.; Menner, H. P.; Ambacher, O.

    2015-11-01

    Admittance-voltage profiling of AlxGa1-xN/GaN heterostructures was used to determine the frequency dependent capacitance and conductance of FET devices in the frequency range from 50 Hz to 1 MHz. The nominally undoped low pressure metal-organic vapor-phase epitaxy structures were grown with an Al-content of 30%. An additional 1 nm thick AlN interlayer was placed in one structure before the Al0.3Ga0.7N layer growth. For frequencies below 108 Hz it is convenient to use equivalent circuits to represent electric or dielectric properties of a material, a method widely used, for example, in impedance spectroscopy. We want to emphasize the relation between frequency dependent admittance-voltage profiling and the corresponding equivalent circuits to the complex dielectric function. Debye and Drude models are used for the description of the frequency dependent admittance profiles in a range of depletion onset of the two-dimensional electron gas. Capacitance- and conductance-frequency profiles are fitted in the entire measured range by combining both models. Based on our results, we see contributions to the two-dimensional electron gas for our samples from surface states (80%) as well as from background doping in the Al0.3Ga0.7N barriers (20%). The specific resistance of the layers below the gate is above 105 Ω cm for both samples and increases with increasing negative bias, i.e., the layers below the gate are essentially depleted. We propose that the resistance due to free charge carriers, determined by the Drude model, is located between gate and drain and, because of the AlN interlayer, the resistance is lowered by a factor of about 30 if compared to the sample without an AlN layer.

  2. Iron nanotube-silica composite (ZVI-S-PCAT modified silica composite) preparation, characterization and application as a recyclable catalytic system for 5-membered ring organic transformations.

    PubMed

    Kour, Gurpreet; Gupta, Monika; Vishwanathan, B; Thirunavukkarasu, K

    2015-09-01

    Iron nanotube silica composite have been synthesized and studied through particle-size analysis, FTIR, SEM-EDX, TEM, XRD, UV, VSM, TGA-DTA and XPS techniques. The application of nanoframeworks as sustainable recyclable catalytic systems has been observed for azole cyclic ring organic transformations. The good reaction yields and characterization through (1)H NMR, (13)C NMR and mass analysis support the performance of the nanoframeworks. We also present here the synthesis of two novel compounds. Also the prepared nanoframework has been observed to show soft magnetism which provides a scope to be used in sensing devices. PMID:26228908

  3. Characterization of Xenorhabdus and Photorhabdus bacteria by Fourier transform mid-infrared spectroscopy with attenuated total reflection (FT-IR/ATR)

    NASA Astrophysics Data System (ADS)

    San-Blas, Ernesto; Cubillán, Néstor; Guerra, Mayamarú; Portillo, Edgar; Esteves, Iván

    The use of Fourier transform mid-infrared spectroscopy with attenuated total reflection for characterizing entomopathogenic bacteria from genera Xenorhabdus and Photorhabdus is evaluated for the first time. The resulting spectra of Xenorhabdus poinarii and Photorhabdus luminiscens were compared with the spectrum of Escherichia coli samples. The absorption spectra generated by the bacteria samples, were very different at the region below 1400 cm-1 which represents the stretching vibrations of phosphate and carbohydrates. Star diagrams of the fingerprint section of nematodes spectra (between 1350 and 1650 cm-1) for separation between spectra was used and showed to be a useful tool for classification purposes.

  4. Advanced oxidation of the antibiotic sulfapyridine by UV/H₂O₂: Characterization of its transformation products and ecotoxicological implications.

    PubMed

    García-Galán, Ma Jesús; Anfruns, Alba; Gonzalez-Olmos, Rafael; Rodriguez-Mozaz, Sara; Comas, Joaquim

    2016-03-01

    The aim of the present work is to investigate, under lab-scale conditions, the removal and transformation of the antibiotic sulfapyridine (SPY) upon advanced oxidation with UV/H2O2. High resolution mass spectrometry (HRMS) analyses by means of an ultra-high pressure liquid chromatography (UHPLC)-linear ion trap high resolution Orbitrap instrument (LTQ-Orbitrap-MS) were carried out in order to elucidate the different transformation products (TPs) generated. The abatement (>99%) of the antibiotic was only achieved after 180 min, highlighting its resilience to elimination and its potential persistence in the environment A total of 10 TPs for SPY were detected and their molecular structures elucidated by means of MS(2) and MS(3) scans. Finally, the combined ecotoxicity at different treatment times was evaluated by means of bioluminescence inhibition assays with the marine bacteria Vibrio fischeri. PMID:26789837

  5. Study and characterization of the irreversible transformation of electrically stressed planar Ti/TiO{sub x}/Ti junctions

    SciTech Connect

    Guillaume, N.; Puyoo, E. Le Berre, M.; Albertini, D.; Baboux, N.; Chevalier, C.; Ayadi, K.; Grégoire, J.; Gautier, B.; Calmon, F.

    2015-10-14

    We investigate the properties and characteristics of planar Ti/TiO{sub x}/Ti junctions, which consist of transverse TiO{sub x} lines drawn on Ti test patterns. Junctions are elaborated by means of local anodic oxidation using atomic force microscopy. An irreversible morphological transformation occurring in a reproducible manner is observed when these planar junctions are electrically stressed under ambient atmosphere. Structural and chemical analyses based on transmission electron microscopy techniques reveal the extension of the initial amorphous TiO{sub x} into a crystalline rutile phase. This irreversible transformation is proven to vanish completely if the electrical stress occurs under vacuum atmosphere. Finally, we carry out temperature dependent electrical measurements in order to elucidate their conduction mechanism: Schottky emission above an ultra-low potential barrier is assumed to dominate under vacuum atmosphere whereas ionic conduction seems to prevail in air.

  6. Characterization of solid phases and study of transformation kinetics in m-chlorofluorobenzene by 35Cl nuclear quadrupole resonance.

    PubMed

    Pérez, Silvina; Wolfenson, Alberto

    2012-02-01

    Polymorphism is of widespread occurrence in the world of molecular crystals. In this work we present experimental results showing the existence of four solid phases in m-chlorofluorobenzene. A glass structure is achieved by quenching the liquid phase at 77 K. This glassy state crystallizes in a disordered phase at T~143 K, which in turn transforms to the high-temperature stable phase (phase I) at T~153 K. Depending on the thermal history of the sample, a different ordered phase (phase III) can be obtained. The disorder is attributed to a molecular orientational disorder. There is no evidence of molecular reorientation in any phase. A study of the disorder-order phase transformation kinetics, using nuclear quadrupole resonance, is presented. The results are analyzed following Cahn's theory. Nucleation seems to take place at grain boundaries. Growth rates for different temperatures have been determined. PMID:22209621

  7. Fourier transform infrared and Raman spectroscopic characterization of homogeneous solution concentration gradients near a container wall at different temperatures

    NASA Technical Reports Server (NTRS)

    Loo, B. H.; Burns, D. H.; Lee, Y. G. L.; Emerson, M. T.

    1991-01-01

    Fourier transform infrared (FTIR) and Raman spectroscopic techniques were used to study the solution concentration gradient in succino nitrile-rich and water-rich homogeneous solutions. The spectroscopic data shows significant concentration dependency. Although FTIR-attenuated total reflectance could not yield surface spectra since the evanescent infrared wave penetrated deep into the bulk solution, it showed that water-rich clusters were decreased at higher temperatures. This result is consistent with the calorimetric results reported earlier.

  8. Characterization of the β-1,3-glucanase gene in peanut (Arachis hypogaea L.) by cloning and genetic transformation.

    PubMed

    Qiao, L X; Ding, X; Wang, H C; Sui, J M; Wang, J-S

    2014-01-01

    Plant β-1,3-glucanases are commonly involved in disease resistance. This report describes the cloning and genetic transformation of a β-1,3-glucanase gene from peanut. The gene was isolated from both the genomic DNA and cDNA of peanut variety Huayu20 by polymerase chain reaction (PCR) and reverse transcription PCR (RT-PCR), respectively. The DNA sequence contained 1471 bp including two exons and one intron, and the coding sequence contained 1047 bp that coded for a 348-amino acid protein with a calculated molecular weight of 38.8 kDa. The sequence was registered in NCBI (GenBank accession No. JQ801335) and was designated as Ah-Glu. As determined by BLAST analysis, the Ah-Glu protein has 42-90% homology with proteins from Oryza sativa (BAC83070.1), Zea mays (NP_001149308), Arabidopsis thaliana (NP_200470.1), Medicago sativa (ABD91577.1), and Glycine max (XP_003530515.1). The over-expression vector pCAMBIA1301-Glu containing Ah-Glu was constructed, confirmed by PCR and restriction enzyme digestion, and transformed into peanut variety Huayu22 by Agrobacterium EHA105-mediated transformation. The putative transformed plants (T0) were confirmed by PCR amplification. RT-PCR analysis and β-glucuronidase (GUS) staining showed that the transferred Ah-Glu was expressed as mRNA and protein. In a laboratory test, the transgenic plants were found to be more resistant to the fungal pathogen Cercospora personata than the non-transgenic plants were. PMID:24668677

  9. FBJ osteosarcoma virus in tissue culture. III. Isolation and characterization of non-virus-producing FBJ-transformed cells.

    PubMed Central

    Levy, J A; Kazan, P L; Reilly, C A; Finkel, M P

    1978-01-01

    Hamster and rat cell lines have been established that have been transformed by FBJ murine sarcoma virus (FBJ-MuSV) but that do not produce virus. The hamster cell line originated from an osteosarcoma that appeared in a hamster inoculated at birth with an extract of a CFNo1 mouse FBJ-osteosarcoma. The rat cell line was obtained by transferring the FBJ-MuSV genome to normal rat kidney cells in the absence of the FBJ type C virus (FBJ-MuLV), which, usually in high concentration, accompanies the FBJ-MuSV. Both transformed hamster and rat cell lines contain the FBJ-MuSV genome, which can be rescued by ecotropic and xenotropic murine type C viruses. This rescued genome produces characteristic FBJ-MuSV foci in tissue culture and, in appropriate animal hosts, induces osteosarcomas typical of those induced by FBJ-MuSV. FBJ-MuSV was isolated originally from a parosteal osteosarcoma that occurred naturally in a mouse. Since there was no previous history of passage of the agent through any other animal species, these non-virus-producing hamster and rat cells transformed by FBJ-MuSV should be very helpful in molecular studies examining the origin of spontaneous sarcoma genomes in mice. PMID:206718

  10. Functional biocompatible magnetite-cellulose nanocomposite fibrous networks: Characterization by fourier transformed infrared spectroscopy, X-ray powder diffraction and field emission scanning electron microscopy analysis

    NASA Astrophysics Data System (ADS)

    Habibi, Neda

    2015-02-01

    The preparation and characterization of functional biocompatible magnetite-cellulose nano-composite fibrous material is described. Magnetite-cellulose nano-composite was prepared by a combination of the solution-based formation of magnetic nano-particles and subsequent coating with amino celluloses. Characterization was accomplished using X-ray powder diffraction (XRD), fourier transformed infrared (FTIR) and field emission scanning electron microscopy (FESEM) analysis. The peaks of Fe3O4 in the XRD pattern of nanocomposite confirm existence of the nanoparticles in the amino cellulose matrix. Magnetite-cellulose particles exhibit an average diameter of roughly 33 nm as demonstrated by field emission scanning electron microscopy. Magnetite nanoparticles were irregular spheres dispersed in the cellulose matrix. The vibration corresponding to the Nsbnd CH3 functional group about 2850 cm-1 is assigned in the FTIR spectra. Functionalized magnetite-cellulose nano-composite polymers have a potential range of application as targeted drug delivery system in biomedical field.

  11. Characterization of metoprolol biodegradation and its transformation products generated in activated sludge batch experiments and in full scale WWTPs.

    PubMed

    Rubirola, A; Llorca, M; Rodriguez-Mozaz, S; Casas, N; Rodriguez-Roda, I; Barceló, D; Buttiglieri, G

    2014-10-15

    Metoprolol (MTP) is a compound of concern, considered as an emerging contaminant due to its high consumption, pseudopersistence and potential ecotoxicity. Activated sludge batch experiments were performed to evaluate the biological transformation of MTP and the formation of transformation products under different treatment conditions. Total MTP removal was obtained in aerobic conditions, and the formation of MTP known metabolites (metoprolol acid (MTPA), α-hydroxymetoprolol (α-HMTP) and O-desmethylmetoprolol (O-DMTP)) and unknown transformation products (TPs) was investigated. The three known metabolites and two new TPs generated along the experiments were identified by liquid chromatography coupled to high resolution mass spectrometry. For the two new TPs plausible structures were proposed based on the tentative identification. MTPA had the major ratio formation for the TPs identified along the experiments (up to 40% of initial MTP concentration after 96 h treatment) and its persistence through biological treatment was proven. Ecotoxicity studies using Vibrio fischeri bioluminescent bacteria in an acute toxicity test showed that MTP and its known TPs are not toxic with the exception of o-DMTP. Finally, MTP and its TPs were monitored in a full scale membrane bioreactor and in a full scale conventional urban wastewater treatment plant (WWTP) and the results were compared with those obtained in batch experiments. α-HMTP was detected for the first time in a WWTP influent whereas MTPA was detected in influent and effluent WWTP samples at much higher levels (up to 100 folds higher) than MTP itself remarking its high persistence. PMID:24973729

  12. Resin characterization in cured graphite fiber reinforced composites using diffuse reflectance-FTIR. [Fourier transform infrared spectroscopy

    NASA Technical Reports Server (NTRS)

    Young, P. R.; Stein, B. A.; Chang, A. C.

    1983-01-01

    The feasibility of using diffuse reflectance in combination with Fourier transform infrared spectroscopy to obtain information on cured graphite fiber reinforced polymeric matrix resin composites was investigated. Several graphite/epoxy, polysulfone, and polyimide composites exposed to thermal or radiation environments were examined. An experimental polyimide-sulfone adhesive tape was also studied during processing. In each case, significant changes in resin molecular structure was observed due to environmental exposure. These changes in molecular structure were correlated with previously observed changes in material properties providing new insights into material behavior.

  13. Characterization of separability and entanglement in (2xD)- and (3xD)-dimensional systems by single-qubit and single-qutrit unitary transformations

    SciTech Connect

    Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2007-10-15

    We investigate the geometric characterization of pure state bipartite entanglement of (2xD)- and (3xD)-dimensional composite quantum systems. To this aim, we analyze the relationship between states and their images under the action of particular classes of local unitary operations. We find that invariance of states under the action of single-qubit and single-qutrit transformations is a necessary and sufficient condition for separability. We demonstrate that in the (2xD)-dimensional case the von Neumann entropy of entanglement is a monotonic function of the minimum squared Euclidean distance between states and their images over the set of single qubit unitary transformations. Moreover, both in the (2xD)- and in the (3xD)-dimensional cases the minimum squared Euclidean distance exactly coincides with the linear entropy [and thus as well with the tangle measure of entanglement in the (2xD)-dimensional case]. These results provide a geometric characterization of entanglement measures originally established in informational frameworks. Consequences and applications of the formalism to quantum critical phenomena in spin systems are discussed.

  14. Synchrotron radiation-based Fourier-transform infrared spectromicroscopy for characterization of the protein/peptide distribution in single microspheres

    PubMed Central

    Wang, Manli; Lu, Xiaolong; Yin, Xianzhen; Tong, Yajun; Peng, Weiwei; Wu, Li; Li, Haiyan; Yang, Yan; Gu, Jingkai; Xiao, Tiqiao; Chen, Min; Zhang, Jiwen

    2015-01-01

    The present study establishes a visualization method for the measurement of the distribution and localization of protein/peptide constituents within a single poly-lactide-co-glycolide (PLGA) microsphere using synchrotron radiation–based Fourier-transform infrared spectromicroscopy (SR-FTIR). The representative infrared wavenumbers specific for protein/peptide (Exenatide) and excipient (PLGA) were identified and chemical maps at the single microsphere level were generated by measuring and plotting the intensity of these specific bands. For quantitative analysis of the distribution within microspheres, Matlab software was used to transform the map file into a 3D matrix and the matrix values specific for the drug and excipient were extracted. Comparison of the normalized SR-FTIR maps of PLGA and Exenatide indicated that PLGA was uniformly distributed, while Exenatide was relatively non-uniformly distributed in the microspheres. In conclusion, SR-FTIR is a rapid, nondestructive and sensitive detection technology to provide the distribution of chemical constituents and functional groups in microparticles and microspheres. PMID:26579456

  15. Synchrotron radiation-based Fourier-transform infrared spectromicroscopy for characterization of the protein/peptide distribution in single microspheres.

    PubMed

    Wang, Manli; Lu, Xiaolong; Yin, Xianzhen; Tong, Yajun; Peng, Weiwei; Wu, Li; Li, Haiyan; Yang, Yan; Gu, Jingkai; Xiao, Tiqiao; Chen, Min; Zhang, Jiwen

    2015-05-01

    The present study establishes a visualization method for the measurement of the distribution and localization of protein/peptide constituents within a single poly-lactide-co-glycolide (PLGA) microsphere using synchrotron radiation-based Fourier-transform infrared spectromicroscopy (SR-FTIR). The representative infrared wavenumbers specific for protein/peptide (Exenatide) and excipient (PLGA) were identified and chemical maps at the single microsphere level were generated by measuring and plotting the intensity of these specific bands. For quantitative analysis of the distribution within microspheres, Matlab software was used to transform the map file into a 3D matrix and the matrix values specific for the drug and excipient were extracted. Comparison of the normalized SR-FTIR maps of PLGA and Exenatide indicated that PLGA was uniformly distributed, while Exenatide was relatively non-uniformly distributed in the microspheres. In conclusion, SR-FTIR is a rapid, nondestructive and sensitive detection technology to provide the distribution of chemical constituents and functional groups in microparticles and microspheres. PMID:26579456

  16. [Development of a handy-type monitoring system for cardiovascular haemodynamic functions based on the volume-compensation and electrical admittance method].

    PubMed

    Song, Yi-lin; Gao, Shu-mei; Ikarashi, Akira; Yamakoshi, Ken-ichi

    2009-03-01

    A handy-type monitoring system for cardiovascular haemodynamic functions based on the volume-compensation and electrical admittance method is developed. In this system, the inconvenient and discomfort due to cuff occlusion of the biological segment for BP measurement is improved by developing a new device using a local pressurization method, the stability for the physiological information detection is improved by developing a new detecting system, and the noise during detection using the system is greatly reduced by using a newly developed nozzle-flapper type electro-pneumatic converter. Also, for electrical admittance cardiography to estimate CO, the applicability of a two-compartment coaxial cylindrical model and the optimal position of a spot-electrode array that is used to replace the conventional band-electrode are discussed in this research. Experimental result shows that the monitoring system should satisfy non-invasive BP and CO measurement on beat by beat, and the comfort of measurement is significantly improved. PMID:19771888

  17. EBSD characterization of high-temperature phase transformations in an Al-Si coating on Cr-Mo steel

    SciTech Connect

    Cheng, Wei-Jen Wang, Chaur-Jeng

    2012-02-15

    5Cr-0.5Mo steel was coated by hot-dipping in a molten bath containing Al-10 wt.% Si. The phase transformation in the aluminide layer during diffusion at 750 Degree-Sign C in static air was analyzed by electron backscatter diffraction. The results show the aluminide layer of the as-coated specimen consisted of an outer Al-Si topcoat, a middle layer formed of scattered {tau}{sub 5(C)}-Al{sub 7}(Fe,Cr){sub 2}Si particles and minor plate-shaped {tau}{sub 4}-Al{sub 4}FeSi{sub 2} and {tau}{sub 6}-Al{sub 4}FeSi phases in the Al-Si matrix and an inner continuous {tau}{sub 5(H)}-Al{sub 7}Fe{sub 2}Si layer, respectively from the coating surface to the steel substrate. The formation of FeAl{sub 3} and Fe{sub 2}Al{sub 5} with {tau}{sub 1}-(Al,Si){sub 5}Fe{sub 3} precipitates can be observed with increasing exposure time at 750 Degree-Sign C. After 5 h of exposure, the Al-Si topcoat has been consumed, and the aluminide layer consisted of Fe{sub 2}Al{sub 5} and a few {tau}{sub 1}-(Al,Si){sub 5}Fe{sub 3} precipitates. The FeAl phase not only formed at the interface between Fe{sub 2}Al{sub 5} and the steel substrate, but also transformed from {tau}{sub 1}-(Al,Si){sub 5}Fe{sub 3} after diffusion for 10 h. With prolonged exposure, the aluminide layer comprised only FeAl{sub 2} and FeAl. - Highlights: Black-Right-Pointing-Pointer EBSD can differentiate phases in aluminide layer with similar chemical compositions. Black-Right-Pointing-Pointer Mapping and EBSPs functions in EBSD provide a reliable phase identification. Black-Right-Pointing-Pointer A phase transformation in the aluminide layer has been described in detail. Black-Right-Pointing-Pointer 5 Fe-Al-Si and 4 Fe-Al intermetallic phases are performed during the diffusion. Black-Right-Pointing-Pointer Cubic {tau}{sub 5(C)}-Al{sub 7} (Fe,Cr){sub 2}Si and hexagonal {tau}{sub 5(H)}-Al{sub 7}(Fe,Cr){sub 2}Si are identified.

  18. Structural characterization of phospholipids by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Marto, J A; White, F M; Seldomridge, S; Marshall, A G

    1995-11-01

    Matrix-assisted laser desorption/ionization (MALDI) Fourier transform ion cyclotron resonance mass spectrometry provides for structural analysis of the principal biological phospholipids: glycerophosphatidylcholine, -ethanolamine, -serine, and -inositol. Both positive and negative molecular or quasimolecular ions are generated in high abundance. Isolated molecular ions may be collisionally activated in the source side of a dual trap mass analyzer, yielding fragments serving to identify the polar head group (positive ion mode) and fatty acid side chains (negative ion mode). Azimuthal quadrupolar excitation following collisionally activated dissociation refocuses productions close to the solenoid axis; subsequent transfer of product ions to the analyzer ion trap allows for high-resolution mass analysis. Cyro-cooling of the sample probe with liquid nitrogen greatly reduces matrix adduction encountered in the negative ion mode. PMID:8633761

  19. Characterizing a large shear-zone with seismic and magnetotelluric methods: The case of the Dead Sea Transform

    USGS Publications Warehouse

    Maercklin, N.; Bedrosian, P.A.; Haberland, C.; Ritter, O.; Ryberg, T.; Weber, M.; Weckmann, U.

    2005-01-01

    Seismic tomography, imaging of seismic scatterers, and magnetotelluric soundings reveal a sharp lithologic contrast along a ???10 km long segment of the Arava Fault (AF), a prominent fault of the southern Dead Sea Transform (DST) in the Middle East. Low seismic velocities and resistivities occur on its western side and higher values east of it, and the boundary between the two units coincides partly with a seismic scattering image. At 1-4 km depth the boundary is offset to the east of the AF surface trace, suggesting that at least two fault strands exist, and that slip occurred on multiple strands throughout the margin's history. A westward fault jump, possibly associated with straightening of a fault bend, explains both our observations and the narrow fault zone observed by others. Copyright 2005 by the American Geophysical Union.

  20. Characterization of plasmonic hole arrays as transparent electrical contacts for organic photovoltaics using high-brightness Fourier transform methods

    PubMed Central

    Camino, Fernando E.; Nam, Chang-Yong; Pang, Yutong T.; Hoy, Jessica; Eisaman, Matthew D.; Black, Charles T.; Sfeir, Matthew Y.

    2014-01-01

    We present a methodology for probing light-matter interactions in prototype photovoltaic devices consisting of an organic semiconductor active layer with a semitransparent metal electrical contact exhibiting surface plasmon-based enhanced optical transmission. We achieve high-spectral irradiance in a spot size of less than 100 μm using a high-brightness laser-driven light source and appropriate coupling optics. Spatially resolved Fourier transform photocurrent spectroscopy in the visible and near-infrared spectral regions allows us to measure external quantum efficiency with high sensitivity in small-area devices (<1 mm2). This allows for rapid fabrication of variable-pitch sub-wavelength hole arrays in metal films for use as transparent electrical contacts, and evaluation of the evanescent and propagating mode coupling to resonances in the active layer. PMID:25705085

  1. Experimental geometry for simultaneous beam characterization and sample imaging allowing for pink beam Fourier transform holography or coherent diffractive imaging

    SciTech Connect

    Flewett, Samuel; Eisebitt, Stefan

    2011-02-20

    One consequence of the self-amplified stimulated emission process used to generate x rays in free electron lasers (FELs) is the intrinsic shot-to-shot variance in the wavelength and temporal coherence. In order to optimize the results from diffractive imaging experiments at FEL sources, it will be advantageous to acquire a means of collecting coherence and spectral information simultaneously with the diffraction pattern from the sample we wish to study. We present a holographic mask geometry, including a grating structure, which can be used to extract both temporal and spatial coherence information alongside the sample scatter from each individual FEL shot and also allows for the real space reconstruction of the sample using either Fourier transform holography or iterative phase retrieval.

  2. Identification and characterization of transforming growth factor β induced gene (TGFBIG) from Branchiostoma belcheri: insights into evolution of TGFBI family.

    PubMed

    Song, Xiaojun; Cai, Lu; Li, Yafang; Zhu, Jiu; Jin, Ping; Chen, Liming; Ma, Fei

    2014-01-01

    The transforming growth factor β induced gene (TGFBIG) encodes a protein (TGFBI) which plays important roles in many biological processes. However, no TGFBIG homolog has been reported in B. belcheri. Here, we identified a TGFBI-like gene from B. belcheri and extensively studied the evolutionary history of TGFBI family. We found that the amphioxus genome contains a TGFBIG homolog designated as AmphiTGFBI which encodes a protein with 5 Fas1 domains. The TGFBIGs were present in a common ancestor with Amphimedon queenslandica. We also demonstrated expression patterns of AmphiTGFBI in five amphioxus tissues. Interestingly, the gene structures and conserved motifs of invertebrate TGFBIGs were found to present regular changes in the evolution. Positive selection and Fas1 domain loss might cause the regular changes of gene structures and conserved motifs in invertebrate TGFBIGs during evolution. Together, our findings provided an insight into the evolution of the TGFBI family. PMID:24140261

  3. Characterization of plasmonic hole arrays as transparent electrical contacts for organic photovoltaics using high-brightness Fourier transform methods

    DOE PAGESBeta

    Camino, Fernando E.; Nam, Chang-Yong; Pang, Yutong T.; Hoy, Jessica; Eisaman, Matthew D.; Black, Charles T.; Sfeir, Matthew Y.

    2014-05-15

    Here we present a methodology for probing light-matter interactions in prototype photovoltaic devices consisting of an organic semiconductor active layer with a semitransparent metal electrical contact exhibiting surface plasmon-based enhanced optical transmission. We achieve high-spectral irradiance in a spot size of less than 100 μm using a high-brightness laser-driven light source and appropriate coupling optics. Spatially resolved Fourier transform photocurrent spectroscopy in the visible and near-infrared spectral regions allows us to measure external quantum efficiency with high sensitivity in small-area devices (<1 mm2). Lastly, this allows for rapid fabrication of variable-pitch sub-wavelength hole arrays in metal films for use asmore » transparent electrical contacts, and evaluation of the evanescent and propagating mode coupling to resonances in the active layer.« less

  4. Characterization of plasmonic hole arrays as transparent electrical contacts for organic photovoltaics using high-brightness Fourier transform methods

    SciTech Connect

    Camino, Fernando E.; Nam, Chang-Yong; Pang, Yutong T.; Hoy, Jessica; Eisaman, Matthew D.; Black, Charles T.; Sfeir, Matthew Y.

    2014-05-15

    Here we present a methodology for probing light-matter interactions in prototype photovoltaic devices consisting of an organic semiconductor active layer with a semitransparent metal electrical contact exhibiting surface plasmon-based enhanced optical transmission. We achieve high-spectral irradiance in a spot size of less than 100 μm using a high-brightness laser-driven light source and appropriate coupling optics. Spatially resolved Fourier transform photocurrent spectroscopy in the visible and near-infrared spectral regions allows us to measure external quantum efficiency with high sensitivity in small-area devices (<1 mm2). Lastly, this allows for rapid fabrication of variable-pitch sub-wavelength hole arrays in metal films for use as transparent electrical contacts, and evaluation of the evanescent and propagating mode coupling to resonances in the active layer.

  5. Simplified three-phase transformer model for electromagnetic transient studies

    SciTech Connect

    Chimklai, S.; Marti, J.R.

    1995-07-01

    This paper presents a simplified high-frequency model for three-phase, two- and three-winding transformers. The model is based on the classical 60-Hz equivalent circuit, extended to high frequencies by the addition of the winding capacitances and the synthesis of the frequency-dependent short-circuit branch by an RLC equivalent network. By retaining the T-form of the classical model, it is possible to separate the frequency-dependent series branch from the constant-valued shunt capacitances. Since the short-circuit branch can be synthesized by a minimum-phase-shift rational approximation, the mathematical complications of fitting mutual impedance or admittance functions are avoided and the model is guaranteed to be numerically absolutely stable. Experimental tests were performed on actual power transformers to determine the parameters of the model. EMTP simulation results are also presented.

  6. Characterization of hyaluronate binding proteins isolated from 3T3 and murine sarcoma virus transformed 3T3 cells

    SciTech Connect

    Turley, E.A.; Moore, D.; Hayden, L.J.

    1987-06-02

    A hyaluronic acid binding fraction was purified from the supernatant media of both 3T3 and murine sarcoma virus (MSV) transformed 3T3 cultures by hyaluronate and immunoaffinity chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis resolved the hyaluronate affinity-purified fraction into three major protein bands of estimated molecular weight (M/sub r,e/) 70K, 66K, and 56K which contained hyaluronate binding activity and which were termed hyaluronate binding proteins (HABP). Hyaluronate affinity chromatography combined with immunoaffinity chromatography, using antibody directed against the larger HABP, allowed a 20-fold purification of HABP. Fractions isolated from 3T3 supernatant medium also contained additional binding molecules in the molecular weight range of 20K. This material was present in vanishingly small amounts and was not detected with a silver stain or with (/sup 35/S)methionine label. The three protein species isolated by hyaluronate affinity chromatography (M/sub r,e/ 70K, 66K, and 56K) were related to one another since they shared antigenic determinants and exhibited similar pI values. In isocratic conditions, HABP occurred as aggregates of up to 580 kilodaltons. Their glycoprotein nature was indicated by their incorporation of /sup 3/H-sugars. Enzyme-linked immunoadsorbent assay showed they were antigenically distinct from other hyaluronate binding proteins such as fibronectin, cartilage link protein, and the hyaluronate binding region of chondroitin sulfate proteoglycan. The results are discussed with regard both to the functional significance of hyaluronate-cell surface interactions in transformed as well as normal cells and to the relationship of HABP to other reported hyaluronate binding proteins.

  7. Preparation, Characterization and Microelectronic Applications of Langmuir Blodgett Films.

    NASA Astrophysics Data System (ADS)

    Maccagno, Pierre Luigi

    This thesis evaluates the use of ultrathin Langmuir Blodgett (LB) films in semiconductor technology. Three different applications are explored: electron-beam resists, dielectric films, and tunneling dimension insulators. Deposition processes are established for LB films of cadmium brassidate, and Poly-Methyl-Methacrylate (PMMA). Film are characterized on the water subphase of the LB trough with a Wilhelmy balance and on various substrates with X-ray diffraction, Grazing Incidence Reflection Fourier Transform Infrared Spectroscopy (GIR FTIR), Scanning Electron Microscopy (SEM), Ellipsometry, Scanning Tunnelling Microscopy (STM) and electrical conduction and admittance measurements. Ultrathin PMMA LB films are shown to behave as excellent e-beam resists. PMMA LB films 10.5nm thick (13 monolayers) have pinhole densities (10/cm^2 ) three orders of magnitude smaller than those spin cast films of the same thickness. Furthermore, the same PMMA LB film thickness is able to protect a 50nm Cr underlayer for well over 13 minutes from chemical etchants. Low energy e-beam exposure of ultrathin PMMA LB films was demonstrated with the STM. The advantages of the STM as a lithography tool is that small diameter (<50nm) low energy (20eV to 100eV) e-beams may be used with LB resist films to obtain submicron resolution and reduced proximity effects due to less scattering of electrons within the ultrathin LB resist. Electrical conduction and admittance of metal/insulator/metal capacitors are studied for various thickness LB PMMA films, and electrode materials. Capacitors with Au electrodes were shorted due to pinholes in the LB film. Shorts were not observed with Al electrodes as a result of the native alumina. The thickness and dielectric constant of PMMA monolayers and Al_2O_3 are obtained. Diverse conduction mechanisms are proposed for Al electrode capacitors separated by no PMMA film; one monolayer; and three or more monolayers. Electrical properties of Au/PMMA/n-Si diodes with

  8. Characterization of a new melanocyte-specific gene (QNR-71) expressed in v-myc-transformed quail neuroretina.

    PubMed Central

    Turque, N; Denhez, F; Martin, P; Planque, N; Bailly, M; Bègue, A; Stéhelin, D; Saule, S

    1996-01-01

    Quail neuroretina cells (QNR) infected with the v-myc-expressing retrovirus MC29 become pigmented after several passages in vitro. After differential screening of a cDNA library constructed from these cells, we have isolated a cDNA clone (QNR-71) which identifies an RNA expressed only in the pigmented layer of the retina and in the epidermis. This gene can also be induced in other cell types transformed by MC29, suggesting that QNR-71 may be regulated by the v-myc protein. Sequence analysis showed that the QNR-71 cDNA exhibits stretches of homologies with melanosomal proteins encoding genes. From bacterially expressed QNR-71 peptides we obtained rabbit antisera able to specifically recognize two proteins of 95 and 100 kDa in pigmented retinal cells, but not in the neuroretina. To study the regulation of QNR-71, we used promoter fragments linked to the CAT reporter gene, in transient co-expression assay. We observed an increase in CAT expression with a c-MYC and microphtalmia (mi) expression vectors. Both MYC and mi activate the QNR-71 promoter through direct binding to a CATGTG site present in the promoter fragment. Images PMID:8670835

  9. Biochemical characterization of the Drosophila dpp protein, a member of the transforming growth factor beta family of growth factors.

    PubMed Central

    Panganiban, G E; Rashka, K E; Neitzel, M D; Hoffmann, F M

    1990-01-01

    The decapentaplegic (dpp) gene of Drosophila melanogaster is required for pattern formation in the embryo and for viability of the epithelial cells in the imaginal disks. The dpp protein product predicted from the DNA sequence is similar to members of a family of growth factors that includes transforming growth factor beta (TGF-beta). We have produced polyclonal antibodies to a recombinant dpp protein made in bacteria and used a metallothionein promoter to express a dpp cDNA in Drosophila S2 cells. Similar to other proteins in the TGF-beta family, the dpp protein produced by the Drosophila cells was proteolytically cleaved, and both portions of the protein were secreted from the cells. The amino-terminal 47-kilodalton (kDa) peptide was found in the medium and in the proteins adhering to the plastic petri dish. The carboxy-terminal peptide, the region with sequence similarity to the active ligand portion of TGF-beta, was found extracellularly as a 30-kDa homodimer. Most of the 30-kDa homodimer was in the S2 cell protein adsorbed onto the surface of the plastic dish. The dpp protein could be released into solution by increased salt concentration and nonionic detergent. Under these conditions, the amino-terminal and carboxy-terminal portions of dpp were not associated in a stable complex. Images PMID:1692958

  10. Fourier Transform Infrared Spectroscopic characterization and optimization of Pb(II) biosorption by fish (Labeo rohita) scales.

    PubMed

    Nadeem, Raziya; Ansari, Tariq Mahmood; Khalid, Ahmad Mukhtar

    2008-08-15

    The present study reports the use of locally available fish (Labeo rohita) scales for Pb(II) removal from aqueous solutions under different experimental conditions. Maximum Pb(II) adsorption (196.8 mg g(-1)) occurred at pH 3.5. Pb(II) sorption was found to be pH, dose, initial metal concentration, contact time and shaking speed dependent while particle size and temperature independent. Experimental data of Pb(II) biosorption onto fish scales fitted well to Freundlich isotherm model in comparison to the model of Langmuir. The fast adsorption process in first 30 min followed by subsequent slow adsorption rate was suitably described by pseudo-second order model. In addition, this study was designed to evaluate the effect of physical and chemical pretreatments on surface properties of fish scales by the application of Fourier Transform Infrared (FTIR) Spectroscopic analysis. Physical pretreatments resulted in partial degradation of some functional groups. Alkaline pretreatments of fish scales did not have any significant influence on the nature of functional groups responsible for Pb(II) uptake, while acidic pretreatments resulted in degeneration of the most of functional groups on biosorbent cell wall. FTIR analysis confirmed the involvement of amino, carboxylic, phosphate and carbonyl groups in Pb(II) biosorption by fish scales. PMID:18242826

  11. Efficient Heterologous Transformation of Chlamydomonas reinhardtii npq2 Mutant with the Zeaxanthin Epoxidase Gene Isolated and Characterized from Chlorella zofingiensis

    PubMed Central

    Couso, Inmaculada; Cordero, Baldo F.; Vargas, María Ángeles; Rodríguez, Herminia

    2012-01-01

    In the violaxanthin cycle, the violaxanthin de-epoxidase and zeaxanthin epoxidase catalyze the inter-conversion between violaxanthin and zeaxanthin in both plants and green algae. The zeaxanthin epoxidase gene from the green microalga Chlorella zofingiensis (Czzep) has been isolated. This gene encodes a polypeptide of 596 amino acids. A single copy of Czzep has been found in the C. zofingiensis genome by Southern blot analysis. qPCR analysis has shown that transcript levels of Czzep were increased after zeaxanthin formation under high light conditions. The functionality of Czzep gene by heterologous genetic complementation in the Chlamydomonas mutant npq2, which lacks zeaxanthin epoxidase (ZEP) activity and accumulates zeaxanthin in all conditions, was analyzed. The Czzep gene was adequately inserted in the pSI105 vector and expressed in npq2. The positive transformants were able to efficiently convert zeaxanthin into violaxanthin, as well as to restore their maximum quantum efficiency of the PSII (Fv/Fm). These results show that Chlamydomonas can be an efficient tool for heterologous expression and metabolic engineering for biotechnological applications. PMID:23118714

  12. Characterization of the surfaces of platinum/tin oxide based catalysts by Fourier Transform Infrared Spectroscopy (FTIR)

    NASA Technical Reports Server (NTRS)

    Keiser, Joseph T.; Upchurch, Billy T.

    1990-01-01

    A Pt/SnO2 catalyst has been developed at NASA Langley that is effective for the oxidation of CO at room temperature (1). A mechanism has been proposed to explain the effectiveness of this catalyst (2), but most of the species involved in this mechanism have not been observed under actual catalytic conditions. A number of these species are potentially detectable by Fourier Transform Infrared Spectroscopy (FTIR), e.g., HOSnO sub x, HO sub y PtO sub z, Pt-CO, and SnHCO3. Therefore a preliminary investigation was conducted to determine what might be learned about this particular catalyst by transmission FTIR. The main advantage of FTIR for this work is that the catalyst can be examined under conditions similar to the actual catalytic conditions. This can be of critical importance since some surface species may exist only when the reaction gases are present. Another advantage of the infrared approach is that since vibrations are probed, subtle chemical details may be obtained. The main disadvantage of this approach is that FTIR is not nearly as sensitive as the Ultra High Vacuum (UHV) surface analytical techniques such as Auger, Electron Spectroscopy for Chemical Analysis (ESCA), Electron Energy Loss Spectroscopy (EELS), etc. Another problem is that the assignment of the observed infrared bands may be difficult.

  13. Characterization of parent and oxygenated-polycyclic aromatic hydrocarbons (PAHs) in Xi'an, China during heating period: An investigation of spatial distribution and transformation.

    PubMed

    Wang, Jingzhi; Hang Ho, Steven Sai; Huang, Rujin; Gao, Meiling; Liu, Suixin; Zhao, Shuyu; Cao, Junji; Wang, Gehui; Shen, Zhenxing; Han, Yongming

    2016-09-01

    Polycyclic aromatic hydrocarbons (PAHs) and its oxygenated derivatives (OPAHs) are toxins in PM2.5. Little information has been known for their transformation in the ambient airs. In this study, PM2.5 samples were collected at 19 sampling sites in Xi'an, China during the heating period, which is classified into: urban residential, university, commercial area, suburban region, and industry. Organic compounds including PAHs, OPAHs, hopanes and cholestanes were quantified. The average of total quantified PAHs and OPAHs concentrations were 196.5 ng/m(3) and 29.4 ng/m(3), respectively, which were consistent with other northern cities in China. Statistical analyses showed that there were significant differences on the distributions of PAHs between urban and suburban regions. The industry also had distinguishable profiles compared with urban residential and commercial area for OPAHs. The greater diversity of OPAHs than PAHs might be due to different primary emission sources and transformation and degradation pathways. The ratios of OPAHs to the corresponding parent PAHs, including 9-fluorenone/fluorene, anthraquinone/anthracene, benz[a]anthracene-7,12-dione/benzo[a]anthracene were 6.2, 12.7, and 1.4, respectively, which were much higher than those for the fresh emissions from coal combustion and biomass burning. These prove the importance of secondary formation and transformation of OPAHs in the ambient airs. Biomarkers such as retene, cyclopenta[CD]pyrene and αα-homohopane were characterized for the source apportionment. With Positive Matrix Factorization (PMF) model analysis, biomass burning was recognized as the most dominant pollution sources for PAHs during the heading period, which accounted for a contribution of 37.1%. Vehicle emission (22.8%) and coal combustion (22.6%) were also contributors in Xi'an. PMID:27323290

  14. Molecular characterization of inhibiting biochar water-extractable substances using electrospray ionization fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Smith, Cameron R; Sleighter, Rachel L; Hatcher, Patrick G; Lee, James W

    2013-01-01

    Biochar has gained significant interest worldwide for its potential use as both a carbon sequestration technique and soil amendment. Recently, research has shown that pinewood-derived biochar water extracts inhibited the growth of aquatic photosynthetic microorganisms, both prokaryotic and eukaryotic algae, while chicken litter- and peanut shell-derived biochar water extracts showed no growth inhibition. With the use of electrodialysis, the pinewood-derived biochar water extract is separated into 3 fractions (anode-isolated, center chamber retained, and cathode-isolated substances) all with varying toxic effects. Because of its ultrahigh resolution and mass precision, electrospray ionization (ESI) coupled to Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) is utilized in this study to analyze biochar water extracts at a molecular level to enhance our understanding of the toxic nature of pinewood-derived biochar water extracts as compared to benign peanut shell-derived biochar water extracts. The molecular composition of pinewood-derived biochar water extracts shows unique carbohydrate ligneous components and sulfur containing condensed ligneous components that are both absent from the peanut shell water extracts and more prevalent in the anode-isolated substances. Using Kendrick mass defect analysis, we also determine that the most likely inhibitor species contain carboxyl and hydroxyl homologous series, both of which are characteristic functional groups hypothesized in our previous research for the inhibitor species. We have suggested that inhibition of aquatic photosynthetic microorganism growth is most likely due to degraded lignin-like species rich in oxygen containing functionalities. From the study conducted here, we show the potential of ultrahigh resolution FTICR-MS as a valuable analytical technique for determining whether certain biochars are safe and benign for use as carbon sequestration and soil amendment. PMID:24180747

  15. Structure of low dielectric constant to extreme low dielectric constant SiCOH films: Fourier transform infrared spectroscopy characterization

    NASA Astrophysics Data System (ADS)

    Grill, Alfred; Neumayer, Deborah A.

    2003-11-01

    Carbon doped oxide dielectrics comprised of Si, C, O, and H (SiCOH) have been prepared by plasma enhanced chemical vapor deposition (PECVD) from mixtures of tetramethylcyclotetrasiloxane (TMCTS) and an organic precursor. The films have been analyzed by determining their elemental composition and by Fourier transform infrared spectroscopy with deconvolution of the absorption peaks. The analysis has shown that PECVD of TMCTS produces a highly crosslinked networked SiCOH film. Dissociation of TMCTS appears to dominate the deposition chemistry as evidenced by the multitude of bonding environments and formation of linear chains and branches. Extensive crosslinking of TMCTS rings occurs through Si-Si, Si-CH2-Si, Si-O-Si, and Si-CH2-O-Si moieties. The films deposited from mixtures of TMCTS and organic precursor incorporate hydrocarbon fragments into the films. This incorporation occurs most probably through the reaction of the organic precursor and the Si-H bonds of TMCTS. Annealing the SiCOH films deposited from TMCTS and organic precursor results in a large loss of carbon and hydrogen from the films resulting from the fragmentation and loss of the incorporated organic component. The deconvolution of the Si-O-Si asymmetric stretching band of the annealed films shows the existence of a larger fraction of a cage structure and a correspondingly smaller fraction of a networked (highly crosslinked) structure in the SiCOH films deposited from mixtures of TMCTS with organic precursor relative to the films deposited from TMCTS only. The evolution of the volatile hydrocarbon fragments during annealing results in the formation of nanopores and subsequent reduction of the dielectric constants of the films to extreme low-k values.

  16. Preparation and in situ Characterization of Surfaces Using Soft-Landing in a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer

    SciTech Connect

    Alvarez, Jormarie; Cooks, Robert G.; Barlow, Stephan E.; Gaspar, Dan J.; Futrell, Jean H.; Laskin, Julia

    2005-06-01

    Mass-selected peptide ions produced by electrospray ionization were deposited onto fluorinated self-assembled monolayer surfaces (FSAM) surfaces by soft-landing using a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially designed for studying interactions of large ions with surfaces. Analysis of the modified surface was performed in situ by combining 2 keV Cs+ secondary ion mass spectrometry with FT-ICR detection of the sputtered ions (FT-ICR-SIMS). Regardless of the initial charge state of the precursor ion, the SIMS mass spectra included singly-protonated peptide fragment ions and peaks characteristic of the surfaces in all cases. In some experiments multiply-protonated peptide ions and [M+Au]+ ions were also observed upon SIMS analysis of modified surfaces. For comparison with the in situ analysis of the modified surfaces, ex situ analysis of some of the modified surfaces was performed by 25 kV Ga+ time of flight ? secondary ion mass spectrometry (ToF-SIMS). The ex situ analysis demonstrated that a significant number of soft-landed peptide ions remain charged on the surface even when exposed to air for several hours after deposition. Charge retention of soft-landed ions dramatically increases the ion yields obtained during SIMS analysis very sensitive detection of deposited material at less than 1% of monolayer coverage. Accumulation of charged species on the surface undergoes saturation due to Coulomb repulsion between charges at close to 30% coverage. We estimated that close to 1 ng of peptide could be deposited on the spot area of 4 mm2 of the FSAM surface without reaching saturation.

  17. Remote characterization of dominant wavelengths of surface folds on lava flows using Lidar and Discrete Fourier Transform analyses

    NASA Astrophysics Data System (ADS)

    Deardorff, N.; Cashman, K.

    2014-12-01

    The crust of lava flows (of all compositions) is commonly folded into arcuate ridges, bent such that the convex ridges point down flow. In theory, the geometry of flow surface folds can be used to constrain the thickness and viscosity of the folding layer (from the fold wavelength) and the compressional stress (from the fold amplitude). Crustal thickness is controlled primarily by lava composition and extent of cooling. Therefore, lavas of more evolved compositions (higher silica content) have thicker crusts, which should generate surface folds with larger wavelengths. We have determined the characteristic scale of surface folds using 1000m along-channel segments from Lidar-derived 3D Digital Terrain Models over a range of lava compositions (53-72 wt% SiO2). All profiles were analyzed by discrete Fourier transform (DFT) analysis in Matlab, used to determine the spatial scale of periodic surface features. The DFT periodograms produce 1D arrays of spectral density over a range of spatial frequencies, which describe the amplitude and spatial scale (wavelength) of lava surface topography. The DFT analysis allows for unbiased measurements of dominant surface fold wavelengths as well as identification of primary and secondary folds (i.e. folds within folds). Measurements of multiple fold generations are not possible from satellite images or in the field on intermediate to high silica blocky lavas. In our analyses, strong signals of surface periodicities were found at multiple frequencies for all lava flows, indicating multiple generations of surface folds. Additionally, mafic to intermediate lavas (<60 wt% SiO2) show a positive correlation between dominant fold wavelengths and wt% silica. This correlation breaks down with high silica lavas (>65 wt% SiO2) which have a much larger range in dominant wavelength (10 - >100m). The deviation in expected dominant wavelengths for high silica flows is likely explained by effective viscosity, which is strongly influenced by lava

  18. Characterization of chemical constituents in Rhodiola Crenulate by high-performance liquid chromatography coupled with Fourier-transform ion cyclotron resonance mass spectrometer (HPLC-FT-ICR MS).

    PubMed

    Han, Fei; Li, Yanting; Mao, Xinjuan; Xu, Rui; Yin, Ran

    2016-05-01

    In this work, an approach using high-performance liquid chromatography coupled with diode-array detection and Fourier-transform ion cyclotron resonance mass spectrometer (HPLC-FT-ICR MS) for the identification and profiling of chemical constituents in Rhodiola crenulata was developed for the first time. The chromatographic separation was achieved on an Inertsil ODS-3 column (150 mm × 4.6 mm,3 µm) using a gradient elution program, and the detection was performed on a Bruker Solarix 7.0 T mass spectrometer equipped with electrospray ionization source in both positive and negative modes. Under the optimized conditions, a total of 48 chemical compounds, including 26 alcohols and their glycosides, 12 flavonoids and their glycosides, 5 flavanols and gallic acid derivatives, 4 organic acids and 1 cyanogenic glycoside were identified or tentatively characterized. The results indicated that the developed HPLC-FT-ICR MS method with ultra-high sensitivity and resolution is suitable for identifying and characterizing the chemical constituents in R. crenulata. And it provides a helpful chemical basis for further research on R. crenulata. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27194521

  19. Identification and characterization of an anti-oxidative stress-associated mutant of Aspergillus fumigatus transformed by Agrobacterium tumefaciens

    PubMed Central

    FAN, ZHONGQI; YU, HUIMEI; GUO, QI; HE, DAN; XUE, BAIJI; XIE, XIANGLI; YOKOYAMA, KOJI; WANG, LI

    2016-01-01

    Aspergillus fumigatus is one of the most common opportunistic pathogenic fungi, surviving in various environmental conditions. Maintenance of the redox homeostasis of the fungus relies upon the well-organized regulation between reactive oxygen species generated by immune cells or its own organelles, and the activated anti-oxidative stress mechanism. To investigate such a mechanism, the present study obtained a number of randomly-inserted mutants of A. fumigatus, mediated by Agrobacterium tumefaciens. In addition, a high throughput hydrogen peroxide screening system was established to examine ~1,000 mutants. A total of 100 mutants exhibited changes in hydrogen peroxide sensitivity, among which a significant increase in sensitivity was observed in the AFM2658 mutant. Further investigations of the mutant were also performed, in which the sequence of this mutant was characterized using thermal asymmetric interlaced-polymerase chain reaction. This revealed that the insertion site was located on chromosome 2 afu1_92, and the 96 bp sequence was knocked out, which partially comprised a sequence localized between the integral membrane protein coding region and the helix-loop-helix transcription factor coding region. A decrease in the levels of anti-oxidative stress-associated mRNAs were observed, and an increase in reactive oxygen species were detected using fluorescence. The results of the present study demonstrated that this sequence may have a protective role in A. fumigatus in the presence of oxidative stress. PMID:26847000

  20. Determination of the valence band offset of MOVPE-grown In0.48Ga0.52P/GaAs multiple quantum wells by admittance spectroscopy

    NASA Astrophysics Data System (ADS)

    Ghezzi, Carlo; Magnanini, Renato; Parisini, Antonella; Tarricone, Luciano; Gombia, Enos; Longo, Massimo

    2008-03-01

    The valence band discontinuity of the lattice matched In0.48Ga0.52P/GaAs heterostructure was determined through a careful analysis of the temperature and frequency dependence of the admittance of p+/MQW/n+ structures, formed by a nominally undoped InGaP/GaAs multiple quantum well region, interposed between p+ and n+ GaAs layers. The heterostructures were grown through metal organic vapor phase epitaxy by using tertiary butyl arsine and tertiary butyl phosphine as alternative precursors for the V-group elements. The growth conditions were optimized for obtaining sharp interfaces and negligible ordering effects in the cation sublattice. Accounting for the temperature dependence of the Fermi energy and the calculated confining energy (10meV) of the heavy holes in the wells, a valence band offset ΔEV=(356±5)meV was derived from the temperature variation of the resonance frequency at which the isothermal conductance over frequency G(ω)/ω curves show a maximum. The experimental uncertainty of this result is significantly low if compared with the wide range (240-400meV) of the previously reported ΔEV values. By considering the band gap difference between InGaP and GaAs, a conduction band offset ΔEC=119meV was estimated. The accuracy of the experimental procedure and the reliability of the main assumptions of the admittance spectroscopy measurements were accurately checked. The obtained results were discussed in light of the large and growing amount of literature data by taking into account the influence of the growth conditions on the physical properties of the InGaP/GaAs quantum wells.

  1. Characterization and petrophysical properties of hydrothemally altered lacustrine volcanistic rock in Geyser Valley (Kamchatka) and its transformation by weathering

    NASA Astrophysics Data System (ADS)

    Gvozdeva, Irina; Zerkal, Oleg; Samarin, Evgeny

    2013-04-01

    smectite causes high hygroscopy of deposits. Rocks are highly porous - of 37-65%, primarily low density - 0,9-1,65 g/cm3 wave velocities - from 0.74 km/s for porous to 3.42 km/sec for dense varieties. All samples are characterized by low strength characteristics: uniaxial compressive strength - 1.2 - 21.7 MPa, uniaxial tension - 0,6-4,7 MPa. By water saturation strength decreases rapidly. Soft coefficient ranges from 0.22 to 0.57. Proving to be on the land surface as a result of slope deformation, volcanic-sedimentary hydrothermally altered rocks are destroyed quickly by precipitation and temperature fluctuations Rock turned to sand, silt and clay depending on the original composition. It was found that often weathered to clayey state tuffites inherit structural and textural features of the primary species. The composition also varies: increased content of clay minerals (to 90%), decreasing the content of zeolites (not to exceed 10%). Quartz and plagioclase form sans fraction. Physical and mechanical properties vary widely: the density of the soil increases slightly up to 1,57-1,59 g/cm3 for sands, 1,2-1,79 g/cm3 for clays, porosity of 51-52% and 49-78% respectively, moisture 22-23% and 43-98/ Clays are in a state of semi-solid to fluid. The high content of smectite determines high plastic properties. Plasticity Index varies widely from 11 to 57. Cohesion and the internal friction angle obtained from shear tests also change widely. For clayey sand grip reaches 137 kPa, internal friction angle - 17 degrees. In clay grip ranges from 13 kPa to 120 kPa, and the internal friction angle - from 11 degrees to 31 degrees. Large variation of properties of the investigated soils is explained by the inhomogeneity of volcano-sedimentary formations both vertically and laterally, varying degrees of hydrothermal alteration and of weathering, fracturing and cracks filling The obtained datas can adequately characterize the volcanic-lacustrine sediments in the valley of the Geysernaya river

  2. High-valent iron (Fe(VI), Fe(V), and Fe(IV)) species in water: characterization and oxidative transformation of estrogenic hormones.

    PubMed

    MachalováŠišková, Karolína; Jančula, Daniel; Drahoš, Bohuslav; Machala, Libor; Babica, Pavel; Alonso, Paula Godoy; Trávníček, Zdeněk; Tuček, Jiří; Maršálek, Blahoslav; Sharma, Virender K; Zbořil, Radek

    2016-07-28

    This paper presents solid state synthesis and characterization of tetra-oxy iron(iv) and iron(v) species in their salt forms (Na4FeO4-Fe(IV) and K3FeO4-Fe(V)). Stability of the synthesized salts, commonly called ferrates, in water was determined by applying the (57)Fe Mössbauer spectroscopy technique. Within 2 s in water, Fe(IV) converted into Fe(III) while Fe(V) transformed into Fe(VI) and Fe(III) at pH = 8.2. Comparatively, Fe(VI) (bought as K2FeO4) remained stable in aqueous solution during the short time period. The oxidative removal efficiency of the high-valent iron species was then tested against five environmentally important estrogenic hormones (estron (E1), 17-β-estradiol (E2), estriol (E3), 17-α-ethinylestradiol (EE2), and diethylstibestrol (DES)) in effluent water of a wastewater treatment plant. Three dosages of iron species (1, 10, and 100 mg L(-1)) were applied to the effluent water. An increase in the concentration of dosages enhanced the removal of estrogens. Both Fe(V) and Fe(VI) were effective in degrading estrogens, but Fe(IV) showed limited oxidation capacity to transform estrogens. The oxidized products of the estrogens were analyzed using Raman spectroscopy and high-performance liquid chromatography-mass spectrometry (HPLC-MS) techniques. Results demonstrated the transformation of estrogens into low molecular weight oxygenated compounds such as quinone-like and opened-aromatic ring species. A detailed study on E1 by using excess Fe(VI) showed the mineralization of the parent compound. The results demonstrate great potential of high-valent iron species in the degradation of endocrine disruptor chemicals like estrogens with several superior aspects including fast reactions, complete degradation and/or formation of benign organic species, and environmentally-acceptable iron oxide by-products. PMID:27344983

  3. Catalytic coherence transformations

    NASA Astrophysics Data System (ADS)

    Bu, Kaifeng; Singh, Uttam; Wu, Junde

    2016-04-01

    Catalytic coherence transformations allow the otherwise impossible state transformations using only incoherent operations with the aid of an auxiliary system with finite coherence that is not being consumed in any way. Here we find the necessary and sufficient conditions for the deterministic and stochastic catalytic coherence transformations between a pair of pure quantum states. In particular, we show that the simultaneous decrease of a family of Rényi entropies of the diagonal parts of the states under consideration is a necessary and sufficient condition for the deterministic catalytic coherence transformations. Similarly, for stochastic catalytic coherence transformations we find the necessary and sufficient conditions for achieving a higher optimal probability of conversion. We thus completely characterize the coherence transformations among pure quantum states under incoherent operations. We give numerous examples to elaborate our results. We also explore the possibility of the same system acting as a catalyst for itself and find that indeed self-catalysis is possible. Further, for the cases where no catalytic coherence transformation is possible we provide entanglement-assisted coherence transformations and find the necessary and sufficient conditions for such transformations.

  4. Structural characterization and profiling of lyso-phospholipids in fresh and in thermally stressed mussels by hydrophilic interaction liquid chromatography-electrospray ionization-Fourier transform mass spectrometry.

    PubMed

    Facchini, Laura; Losito, Ilario; Cianci, Costantina; Cataldi, Tommaso R I; Palmisano, Francesco

    2016-07-01

    The separation efficiency of hydrophilic interaction liquid chromatography and the high resolution/accuracy of electrospray ionization-Fourier transform MS were successfully applied to the detailed characterization of lyso-phosphatidylcholines (LPCs) and lyso-phosphatidylethanolamines (LPEs) contained in the lipid extracts of Mytilus galloprovincialis (Mediterranean mussel). As a result, 57 LPCs, including regio- and positional isomers, and 45 LPEs, including acyl and plasma(e)nyl species, were identified. Four lyso-phosphonocholines were also identified among mussel Lyso-Phospholipids. To the best of our knowledge this represents the first characterization, at a molecular level, ever reported for LPEs in mussels. No significant variation was observed in the composition of both LPCs and LPEs when mussels were refrigerated at +4°C for up to 48 h, i.e. under conditions usually employed for seafood transportation and storage. Treatments mimicking more severe thermal stresses, namely eight day-refrigeration at + 4°C, two week-freezing at -15°C and 6 h-storage at 25°C, resulted in a significant increase in the molar abundance of LPCs and LPEs (expressed with respect to that of their precursors, PCs and PEs, respectively) and was accompanied by the death of all or part of the molluscs. These results were interpreted invoking the generation of lyso-phospholipids, mediated by endogenous phospholipases, as an intermediate process toward the partial replacement of side chains in phospholipids, perhaps functional to a better adaptation of mussels to adverse temperature conditions. Interestingly, the relative abundances of specific compounds belonging to the LPC and LPE classes were found to follow the seasonal variations of sea temperature. PMID:26860242

  5. Comparing Laser Desorption Ionization and Atmospheric Pressure Photoionization Coupled to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry To Characterize Shale Oils at the Molecular Level

    USGS Publications Warehouse

    Cho, Yunjo; Jin, Jang Mi; Witt, Matthias; Birdwell, Justin E.; Na, Jeong-Geol; Roh, Nam-Sun; Kim, Sunghwan

    2013-01-01

    Laser desorption ionization (LDI) coupled to Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was used to analyze shale oils. Previous work showed that LDI is a sensitive ionization technique for assessing aromatic nitrogen compounds, and oils generated from Green River Formation oil shales are well-documented as being rich in nitrogen. The data presented here demonstrate that LDI is effective in ionizing high-double-bond-equivalent (DBE) compounds and, therefore, is a suitable method for characterizing compounds with condensed structures. Additionally, LDI generates radical cations and protonated ions concurrently, the distribution of which depends upon the molecular structures and elemental compositions, and the basicity of compounds is closely related to the generation of protonated ions. This study demonstrates that LDI FT-ICR MS is an effective ionization technique for use in the study of shale oils at the molecular level. To the best of our knowledge, this is the first time that LDI FT-ICR MS has been applied to shale oils.

  6. Characterization of organic material in ice core samples from North America, Greenland, and Antarctica using ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry

    NASA Astrophysics Data System (ADS)

    Catanzano, V.; Grannas, A. M.; Sleighter, R. L.; Hatcher, P. G.

    2013-12-01

    Historically, it has been an analytical challenge to detect and identify the organic components present in ice cores, due to the low abundance of organic carbon. In order to detect and characterize the small amounts of organic matter in ice cores, ultra high resolution instrumentation is required. Here we report the use of ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry, coupled with electrospray ionization, to identify the molecular formulas and compound classes of organic matter in both modern and ancient ice core and glacial samples from Wyoming, Greenland, and Antarctica. A suite of 21 samples were analyzed and thousands of distinct molecular species were identified in each sample, providing clues to the nature and sources of organic matter in these regions. Major biochemical classes of compounds were detected such as lignins, tannins, carbohydrates, proteins, lipids, unsaturated hydrocarbons, and condensed aromatic compounds. We will compare the nature of the organic matter present in the samples in order to determine the differences in dominant organic compound classes and in heteroatom (nitrogen and sulfur) abundance. By analyzing these differences, it is possible to investigate the historical patterns of organic matter deposition/source, and begin to investigate the influence of climate change, volcanism, and onset of the industrial revolution on the nature of organic matter preserved in ice cores.

  7. Structural characterization of arginine-vasopressin and lysine-vasopressin by Fourier- transform ion cyclotron resonance mass spectrometry and infrared multiphoton dissociation.

    PubMed

    Bianco, Giuliana; Battista, Fabio; Buchicchio, Alessandro; Amarena, Concetta G; Schmitt-Kopplin, Philippe; Guerrieri, Antonio

    2015-01-01

    Arginine-vasopressin (AVP) and lysine-vasopressin (LVP) were analyzed by reversed-phase liquid chromatography/mass spectrometry (LC-MS) using Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) electrospray ionization (ESI) in the positive ion mode. LVP and AVP exhibited the protonated adduct [M+H](+) as the predominant ion at m/z 1056.43965 and at m/z 1084.44561, respectively. Infrared multiphoton dissociation (IRMPD), using a CO(2) laser source at a wavelength of 10.6 μm, was applied to protonated vasopressin molecules. The IRMPD mass spectra presented abundant mass fragments essential for a complete structural information. Several fragment ions, shared between two target molecules, are discussed in detail. Some previously unpublished fragments were identified unambiguously utilizing the high resolution and accurate mass information provided by the FT-ICR mass spectrometer. The opening of the disulfide loop and the cleavage of the peptide bonds within the ring were observed even under low-energy fragmentation conditions. Coupling the high-performance FT-ICR mass spectrometer with IRMPD as a contemporary fragmentation technique proved to be very promising for the structural characterization of vasopressin. PMID:26307701

  8. ThyroScreen system: high resolution ultrasound thyroid image characterization into benign and malignant classes using novel combination of texture and discrete wavelet transform.

    PubMed

    Acharya, U Rajendra; Faust, Oliver; Sree, S Vinitha; Molinari, Filippo; Suri, Jasjit S

    2012-08-01

    Using right equipment and well trained personnel, ultrasound of the neck can detect a large number of non-palpable thyroid nodules. However, this technique often suffers from subjective interpretations and poor accuracy in the differential diagnosis of malignant and benign thyroid lesions. Therefore, we developed an automated identification system based on knowledge representation techniques for characterizing the intra-nodular vascularization of thyroid lesions. Twenty nodules (10 benign and 10 malignant), taken from 3-D high resolution ultrasound (HRUS) images were used for this work. Malignancy was confirmed using fine needle aspiration biopsy and subsequent histological studies. A combination of discrete wavelet transformation (DWT) and texture algorithms were used to extract relevant features from the thyroid images. These features were fed to different configurations of AdaBoost classifier. The performance of these configurations was compared using receiver operating characteristic (ROC) curves. Our results show that the combination of texture features and DWT features presented an accuracy value higher than that reported in the literature. Among the different classifier setups, the perceptron based AdaBoost yielded very good result and the area under the ROC curve was 1 and classification accuracy, sensitivity and specificity were 100%. Finally, we have composed an Integrated Index called thyroid malignancy index (TMI) made up of these DWT and texture features, to facilitate distinguishing and diagnosing benign or malignant nodules using just one index or number. This index would help the clinicians in more quantitative assessment of the thyroid nodules. PMID:22054816

  9. Surface morphology characterization of pentacene thin film and its substrate with under-layers by power spectral density using fast Fourier transform algorithms

    NASA Astrophysics Data System (ADS)

    Itoh, Taketsugu; Yamauchi, Noriyoshi

    2007-05-01

    Surface morphology of pentacene thin films and their substrates with under-layers is characterized by using atomic force microscopy (AFM). The power values of power spectral density (PSD) for the AFM digital data were determined by the fast Fourier transform (FFT) algorithms instead of the root-mean-square (rms) and peak-to-valley value. The PSD plots of pentacene films on glass substrate are successfully approximated by the k-correlation model. The pentacene film growth is interpreted the intermediation of the bulk and surface diffusion by parameter C of k-correlation model. The PSD plots of pentacene film on Au under-layer is approximated by using the linear continuum model (LCM) instead of the combination model of the k-correlation model and Gaussian function. The PSD plots of SiO 2 layer on Au under-layer as a gate insulator on a gate electrode of organic thin film transistors (OTFTs) have three power values of PSD. It is interpreted that the specific three PSD power values are caused by the planarization of the smooth SiO 2 layer to rough Au under-layer.

  10. Electrical characteristics of gadolinium gallium oxide/gallium oxide insulators on GaAs and In0.53Ga0.47As in metal-oxide-semiconductor field effect transistors - admittance and subthreshold characteristics

    NASA Astrophysics Data System (ADS)

    Paterson, G. W.; Bentley, S. J.; Holland, M. C.; Thayne, I. G.; Long, A. R.

    2011-09-01

    The admittances and subthreshold characteristics of capacitors and MOSFETs on buried InxGa1-xAs channel wafers with a dielectric stack of Gd0.25Ga0.15O0.6/Ga2O3 deposited on GaAs and In0.53Ga0.47As are reported. Both the GaAs and InGaAs interface samples show admittance characteristics indicative of the presence of defect states within the oxide, in agreement with previously reported data from the same oxides on n+ substrates. The interface state model is applied to the admittance data to extract an apparent interface state density (Dit) that includes interface and oxide states. The Dit profiles are very different and have pronounced effects on the device performance. The device subthreshold swings (SS) at low source-drain voltages are also used to extract an apparent Dit. A simple method is used to estimate the Fermi-level position within the bandgap (Et) at threshold, and the resulting Dit(Et) are found to be in good agreement with the admittance data. The importance of proper interpretation of SS and Dit in general and in GaAs interface devices in particular is emphasized. A model that accounts for the logarithmic sweep rate dependence of the extracted Dit due to the presence of oxide states is reported and used to estimate their density from SS measurements. The implications of the band parameters of an oxide with defect states within it for the comparison of different oxides on the same substrate and the issues around the comparison of results in general are discussed.

  11. A simple, sensitive and non-destructive technique for characterizing bovine dental enamel erosion: attenuated total reflection Fourier transform infrared spectroscopy.

    PubMed

    Kim, In-Hye; Son, Jun Sik; Min, Bong Ki; Kim, Young Kyoung; Kim, Kyo-Han; Kwon, Tae-Yub

    2016-01-01

    Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Deionized water (control) and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth (110) were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 °C. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers' microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ν1, ν3 phosphate contour: the ratio of the height amplitude of ν3 PO4 to that of ν1 PO4 (Method 1) and the shift of the ν3 PO4 peak to a higher wavenumber (Method 2). The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy (P<0.001). Method 1 was the most sensitive to these changes, followed by surface hardness change measurements and Method 2. This study suggests that ATR-FTIR spectroscopy is potentially advantageous over the microhardness test as a simple, non-destructive, sensitive technique for the quantification of enamel erosion. PMID:27025266

  12. Characterization of skin abnormalities in a mouse model of osteogenesis imperfecta using high resolution magnetic resonance imaging and Fourier transform infrared imaging spectroscopy.

    PubMed

    Canuto, H C; Fishbein, K W; Huang, A; Doty, S B; Herbert, R A; Peckham, J; Pleshko, N; Spencer, R G

    2012-01-01

    Evaluation of the skin phenotype in osteogenesis imperfecta (OI) typically involves biochemical measurements, such as histologic or biochemical assessment of the collagen produced from biopsy-derived dermal fibroblasts. As an alternative, the current study utilized non-invasive magnetic resonance imaging (MRI) microscopy and optical spectroscopy to define biophysical characteristics of skin in an animal model of OI. MRI of skin harvested from control, homozygous oim/oim and heterozygous oim/+ mice demonstrated several differences in anatomic and biophysical properties. Fourier transform infrared imaging spectroscopy (FT-IRIS) was used to interpret observed MRI signal characteristics in terms of chemical composition. Differences between wild-type and OI mouse skin included the appearance of a collagen-depleted lower dermal layer containing prominent hair follicles in the oim/oim mice, accounting for 55% of skin thickness in these. The MRI magnetization transfer rate was lower by 50% in this layer as compared to the upper dermis, consistent with lower collagen content. The MRI transverse relaxation time, T2, was greater by 30% in the dermis of the oim/oim mice compared to controls, consistent with a more highly hydrated collagen network. Similarly, an FT-IRIS-defined measure of collagen integrity was 30% lower in the oim/oim mice. We conclude that characterization of phenotypic differences between the skin of OI and wild-type mice by MRI and FT-IRIS is feasible, and that these techniques provide powerful complementary approaches for the analysis of the skin phenotype in animal models of disease. PMID:21845737

  13. A simple, sensitive and non-destructive technique for characterizing bovine dental enamel erosion: attenuated total reflection Fourier transform infrared spectroscopy

    PubMed Central

    Kim, In-Hye; Son, Jun Sik; Min, Bong Ki; Kim, Young Kyoung; Kim, Kyo-Han; Kwon, Tae-Yub

    2016-01-01

    Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Deionized water (control) and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth (110) were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 °C. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers' microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ν1, ν3 phosphate contour: the ratio of the height amplitude of ν3 PO4 to that of ν1 PO4 (Method 1) and the shift of the ν3 PO4 peak to a higher wavenumber (Method 2). The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy (P<0.001). Method 1 was the most sensitive to these changes, followed by surface hardness change measurements and Method 2. This study suggests that ATR-FTIR spectroscopy is potentially advantageous over the microhardness test as a simple, non-destructive, sensitive technique for the quantification of enamel erosion. PMID:27025266

  14. Design and Characterization of a High-power Laser-induced Acoustic Desorption (LIAD) Probe Coupled with a Fourier-transform Ion Cyclotron Resonance Mass Spectrometer

    PubMed Central

    Shea, Ryan C.; Habicht, Steven C.; Vaughn, Weldon E.; Kenttämaa, Hilkka I.

    2008-01-01

    We report here the construction and characterization of a high-power laser-induced acoustic desorption (LIAD) probe designed for Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometers to facilitate analysis of non-volatile, thermally labile compounds. This “next generation” LIAD probe offers significant improvements in sensitivity and desorption efficiency for analytes with larger molecular weights via the use of higher laser irradiances. Unlike the previous probes which utilized a power limiting optical fiber to transmit the laser pulses through the probe, this probe employs a set of mirrors and a focusing lens. At the end of the probe, the energy from the laser pulses propagates through a thin metal foil as an acoustic wave, resulting in desorption of neutral molecules from the opposite side of the foil. Following desorption, the molecules can be ionized by electron impact or chemical ionization. Almost an order of magnitude greater power density (up to 5.0 × 109 W/cm2) is achievable on the backside of the foil with the high-power LIAD probe compared to the earlier LIAD probes (maximum power density ~9.0 × 108 W/cm2). The use of higher laser irradiances is demonstrated not to cause fragmentation of the analyte. The use of higher laser irradiances increases sensitivity since it results in the evaporation of a greater number of molecules per laser pulse. Measurement of the average velocities of LIAD evaporated molecules demonstrates that higher laser irradiances do not correlate with higher velocities of the gaseous analyte molecules. PMID:17319645

  15. Enhanced tumor formation in cyclin D1 x transforming growth factor beta1 double transgenic mice with characterization by magnetic resonance imaging.

    PubMed

    Deane, Natasha G; Lee, Haakil; Hamaamen, Jalal; Ruley, Anna; Washington, M Kay; LaFleur, Bonnie; Thorgeirsson, Snorri S; Price, Ronald; Beauchamp, R Daniel

    2004-02-15

    Transgenic mice that overexpress cyclin D1 protein in the liver develop liver carcinomas with high penetrance. Transforming growth factor beta (TGF-beta) serves as either an epithelial cell growth inhibitor or a tumor promoter, depending on the cellular context. We interbred LFABP-cyclin D1 and Alb-TGF-beta1 transgenic mice to produce cyclin D1/TGF-beta1 double transgenic mice and followed the development of liver tumors over time, characterizing cellular and molecular changes, tumor incidence, tumor burden, and tumor physiology noninvasively by magnetic resonance imaging. Compared with age-matched LFABP-cyclin D1 single transgenic littermates, cyclin D1/TGF-beta1 mice exhibited a significant increase in tumor incidence. Tumor multiplicity, tumor burden, and tumor heterogeneity were higher in cyclin D1/TGF-beta1 mice compared with single transgenic littermates. Characteristics of cyclin D1/TGF-beta1 livers correlated with a marked induction of the peripheral periductal oval cell/stem cell compartment of the liver. A number of cancerous lesions from cyclin D1/TGF-beta1 mice exhibited unique features such as ductal plate malformations and hemorrhagic nodules. Some lesions were contiguous with the severely diseased background liver and, in some cases, replaced the normal architecture of the entire organ. Cyclin D1/TGF-beta1 lesions, in particular, were associated with malignant features such as areas of vascular invasion by hepatocytes and heterogeneous hyperintensity of signal on T2-weighted magnetic resonance imaging. These findings demonstrate that TGF-beta1 promotes stem cell activation and tumor progression in the context of cyclin D1 overexpression in the liver. PMID:14973059

  16. Ear-canal acoustic admittance and reflectance measurements in human neonates. II. Predictions of middle-ear dysfunction and sensorineural hearing loss

    NASA Astrophysics Data System (ADS)

    Keefe, Douglas H.; Gorga, Michael P.; Neely, Stephen T.; Zhao, Fei; Vohr, Betty R.

    2003-01-01

    This report describes relationships between middle-ear measurements of acoustic admittance and energy reflectance (YR) and measurements of hearing status using visual reinforcement audiometry in a neonatal hearing-screening population. Analyses were performed on 2638 ears in which combined measurements were obtained [Norton et al., Ear Hear. 21, 348-356 (2000)]. The measurements included distortion-product otoacoustic emissions (DPOAE), transient evoked otoacoustic emissions (TEOAE), and auditory brainstem responses (ABR). Models to predict hearing status using DPOAEs, TEOAEs, or ABRs were each improved by the addition of the YR factors as interactions, in which factors were calculated using factor loadings from Keefe et al. [J. Acoust. Soc. Am. 113, 389-406 (2003)]. This result suggests that information on middle-ear status improves the ability to predict hearing status. The YR factors were used to construct a middle-ear dysfunction test on 1027 normal-hearing ears in which DPOAE and TEOAE responses were either both present or both absent, the latter condition being viewed as indicative of middle-ear dysfunction. The middle-ear dysfunction test classified these ears with a nonparametric area (A) under the relative operating characteristic curve of A=0.86, and classified normal-hearing ears that failed two-stage hearing-screening tests with areas A=0.84 for DPOAE/ABR, and A=0.81 for TEOAE/ABR tests. The middle-ear dysfunction test adequately generalized to a new sample population (A=0.82).

  17. Reading Transformation

    ERIC Educational Resources Information Center

    Reeves, Melinda

    2006-01-01

    The parents of students who attend Decatur High School thought that there was little hope of their kids going on to college. After a year or so in Decatur's reading program, their sons and daughters were both transformed and college bound. In this article, the author describes how Decatur was able to successfully transform their students. Seven…

  18. Lightweight transformer

    SciTech Connect

    Swallom, D.W.; Enos, G.

    1990-05-01

    The technical effort described in this report relates to the program that was performed to design, fabricate, and test a lightweight transformer for Strategic Defense Initiative Organization (SDIO) mission requirements. The objectives of this program were two-fold: (1) design and fabricate a lightweight transformer using liquid hydrogen as the coolant; and (2) test the completed transformer assembly with a low voltage, dc power source. Although the full power testing with liquid helium was not completed, the program demonstrated the viability of the design approach. The lightweight transformer was designed and fabricated, and low and moderate power testing was completed. The transformer is a liquid hydrogen cooled air core transformer that uses thin copper for its primary and secondary windings. The winding mass was approximately 12 kg, or 0.03 kg/kW. Further refinements of the design to a partial air core transformer could potentially reduce the winding mass to as low as 4 or 5 kg, or 0.0125 kg/kW. No attempt was made on this program to reduce the mass of the related structural components or cryogenic container. 8 refs., 39 figs., 2 tabs.

  19. Transformational Grammar and Cognitive Psycholinguistics.

    ERIC Educational Resources Information Center

    Lester, Mark

    1973-01-01

    An overview of Noam Chomsky's theories about transformational grammar and phonology is given. Since Chomsky was interested in characterizing what it is to know a language, the ways in which we demonstrate knowledge of our native language are discussed in detail. Particular emphasis is placed on describing how the transformational approach actually…

  20. CHARACTERIZATION OF PCB (POLYCHLORINATED BIPHENYL) TRANSFORMER/CAPACITOR FLUIDS AND CORRELATION WITH PCDDS (POLYCHLORINATED DIBENZO-P-DIOXINS) AND PCDFS (POLYCHLORINATED DIBENZOFURANS) IN SOOT

    EPA Science Inventory

    Dielectric fluids in transformers and capacitors often contain polychlorinated biphenyls (PCBs) or chlorobenzenes. These substances may generate polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs) under certain conditions of combustion/pyrolysis. W...

  1. Triple transformation

    NASA Astrophysics Data System (ADS)

    Khan, Farrukh I.; Schinn, Dustin S.

    2013-08-01

    A new business plan that enables policy transformation and resource mobilization at the national and international level, while improving access to resources, will allow the Green Climate Fund to integrate development goals and action on climate change.

  2. Covariant Transform

    NASA Astrophysics Data System (ADS)

    Kisil, Vladimir V.

    2011-03-01

    Dedicated to the memory of Cora Sadosky The paper develops theory of covariant transform, which is inspired by the wavelet construction. It was observed that many interesting types of wavelets (or coherent states) arise from group representations which are not square integrable or vacuum vectors which are not admissible. Covariant transform extends an applicability of the popular wavelets construction to classic examples like the Hardy space H2, Banach spaces, covariant functional calculus and many others.

  3. Dielectric relaxation in hafnium oxide: A study of transient currents and admittance spectroscopy in HfO2 metal-insulator-metal devices

    NASA Astrophysics Data System (ADS)

    Mannequin, C.; Gonon, P.; Vallée, C.; Bsiesy, A.; Grampeix, H.; Jousseaume, V.

    2011-11-01

    Dielectric relaxation is studied in 10 nm HfO2 thin films which are deposited by atomic layer deposition on TiN and Pt electrodes. Transient currents are recorded from 10-3 s to 10 s, as a function of bias (0.1 V to 1 V) and temperature (20 °C to 180 °C). A Curie-von Schweidler law is observed, I = Q0/tα. The power law exponent α is constant with bias and strongly depends on the temperature (varying in the 0.65-1.05 range, with a peak at 75 °C). The amplitude Q0 is described by a relation of the form Q0 = C0Vβ, where the factor C0 is weakly activated and the exponent β varies with temperature (in the 0.9-1.5 range as T varies). Transient currents are discussed along with tunneling based models from the literature. To complement transient current experiments, admittance spectroscopy (conductance G and capacitance C) is performed at low frequencies, from 0.01 Hz to 10 kHz. The dispersion law of the conductance is of the form G ˜ ωs. The capacitance is the sum of two terms, a non-dispersive term (C∞) and a low-frequency dispersive term, CLF ˜ ω-n. The critical exponents s and n verify s ≈ α and n ≈ 1-α. At room temperature, the dielectric constant is expressed as ɛ' = Δɛ' f-n+ ɛ'∞, where ɛ'∞ = 11.1, n ≈ 0.2/0.3 (Pt/TiN), and Δɛ' ≈ 1.5/0.7 (Pt/TiN).

  4. Characterization of Archaeological Sediments Using Fourier Transform Infrared (FT-IR) and Portable X-ray Fluorescence (pXRF): An Application to Formative Period Pyro-Industrial Sites in Pacific Coastal Southern Chiapas, Mexico.

    PubMed

    Neff, Hector; Bigney, Scott J; Sakai, Sachiko; Burger, Paul R; Garfin, Timothy; George, Richard G; Culleton, Brendan J; Kennett, Douglas J

    2016-01-01

    Archaeological sediments from mounds within the mangrove zone of far-southern Pacific coastal Chiapas, Mexico, are characterized in order to test the hypothesis that specialized pyro-technological activities of the region's prehistoric inhabitants (salt and ceramic production) created the accumulations visible today. Fourier transform infrared spectroscopy (FT-IR) is used to characterize sediment mineralogy, while portable X-ray fluorescence (pXRF) is used to determine elemental concentrations. Elemental characterization of natural sediments by both instrumental neutron activation analysis (INAA) and pXRF also contribute to understanding of processes that created the archaeological deposits. Radiocarbon dates combined with typological analysis of ceramics indicate that pyro-industrial activity in the mangrove zone peaked during the Late Formative and Terminal Formative periods, when population and monumental activity on the coastal plain and piedmont were also at their peaks. PMID:26767637

  5. SHARP transformation

    NASA Astrophysics Data System (ADS)

    Wyatt, Stephan

    2004-08-01

    The U.S. Navy"s SHAred Reconnaissance Pod (SHARP) employs the Recon/Optical, Inc. (ROI) CA-279 dual spectral band (visible/IR) digital cameras operating from an F-18E/F aircraft to perform low-to-high altitude reconnaissance missions. SHARP has proven itself combat worthy, with a rapid transition from development to operational deployment culminating in a highly reliable and effective reconnaissance capability for joint forces operating in Operation Iraqi Freedom (OIF). The U.S. Navy"s intelligence, surveillance and reconnaissance (ISR) roadmap transforms the SHARP system from being solely an independent reconnaissance sensor to a node in the growing Joint ISR network. ROI and the U.S. Navy have combined their resources to ensure the system"s transformation continues to follow the ISR road map. Pre-planned product improvements (P3I) for the CA-270 camera systems will lead the way in that transformation.

  6. On spinors transformations

    NASA Astrophysics Data System (ADS)

    Budinich, Marco

    2016-07-01

    We begin showing that for even dimensional vector spaces V all automorphisms of their Clifford algebras are inner. So all orthogonal transformations of V are restrictions to V of inner automorphisms of the algebra. Thus under orthogonal transformations P and T—space and time reversal—all algebra elements, including vectors v and spinors φ, transform as v → xvx-1 and φ → xφx-1 for some algebra element x. We show that while under combined PT spinor φ → xφx-1 remains in its spinor space, under P or T separately φ goes to a different spinor space and may have opposite chirality. We conclude with a preliminary characterization of inner automorphisms with respect to their property to change, or not, spinor spaces.

  7. FOURIER TRANSFORM INFRARED PHOTOACOUSTIC SPECTROSCOPY CHARACTERIZATION OF SULFUR-OXYGEN SPECIES RESULTING FROM THE REACTION OF SO2 WITH CAO AND CACO3

    EPA Science Inventory

    Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) has been used to investigate the reaction of SO2 in He with CaO and CaCO3 particles at temperatures between 25 and 900 C. SO2 reacts with CaC at 25 C, while the reaction of Ca-CO3 with SO2 is first evident at 550 C ...

  8. Characterization of the Aldehydes and Their Transformations Induced by UV Irradiation and Air Exposure of White Guanxi Honey Pummelo (Citrus Grandis (L.) Osbeck) Essential Oil.

    PubMed

    Li, Li Jun; Hong, Peng; Chen, Feng; Sun, Hao; Yang, Yuan Fan; Yu, Xiang; Huang, Gao Ling; Wu, Li Ming; Ni, Hui

    2016-06-22

    Aldehydes are key aroma contributors of citrus essential oils. White Guanxi honey pummelo essential oil (WPEO) was investigated in its aldehyde constituents and their transformations induced by UV irradiation and air exposure by GC-MS, GC-O, and sensory evaluation. Nine aldehydes, i.e., octanal, nonanal, citronellal, decanal, trans-citral, cis-citral, perilla aldehyde, dodecanal, and dodecenal, were detected in WPEO. After treatment, the content of citronellal increased, but the concentrations of other aldehydes decreased. The aliphatic aldehydes were transformed to organic acids. Citral was transformed to neric acid, geranic acid, and cyclocitral. Aldehyde transformation caused a remarkable decrease in the minty, herbaceous, and lemon notes of WPEO. In fresh WPEO, β-myrcene, d-limonene, octanal, decanal, cis-citral, trans-citral, and dodecenal had the highest odor dilution folds. After the treatment, the dilution folds of decanal, cis-citral, trans-citral, and dodecenal decreased dramatically. This result provides information for the production and storage of aldehyde-containing products. PMID:27226192

  9. Transformation Time

    ERIC Educational Resources Information Center

    Berry, John N., III

    2007-01-01

    The program for the march by librarians on America's capital for the American Library Association (ALA) conference is predictably loaded with lobbying, legislation, and DC tours. It also abounds with professional opportunity and reflects the impact of Leslie Burger, one of the most activist ALA presidents in recent history. Her "Transformation"…

  10. Transformation & Metamorphosis

    ERIC Educational Resources Information Center

    Lott, Debra

    2009-01-01

    The sculptures of Canadian artist Brian Jungen are a great inspiration for a lesson on creating new forms. Jungen transforms found objects into unique creations without fully concealing their original form or purpose. Frank Stella's sculpture series, including "K.132,2007" made of stainless steel and spray paint, is another great example of…

  11. Transforming Schools.

    ERIC Educational Resources Information Center

    Cookson, Peter W., Jr., Ed.; Schneider, Barbara, Ed.

    The authors in this book address the issues that relate to the crisis in American education and review some of the proposed solutions. To transform education, schools must be examined as social systems that are interrelated with families, communities, and the world of work. Following the introduction, section 1, "Conditions for Educational…

  12. Electrical characterization of coupled and uncoupled MEMS ultrasonic transducers.

    PubMed

    Oppenheim, Irving J; Jain, Akash; Greve, David W

    2003-03-01

    We report electrical characterization of micromachined polysilicon capacitive diaphragms for use as ultrasonic transducers. Admittance measurements yield insight into the resonant behavior and also the damping resulting from ultrasonic radiation and frictional forces caused by the etch release holes. Unbonded transducers exhibit sharp resonances with Q values that increase with decreasing air pressure. We also report for the first time direct bonding of these transducers to solid surfaces. Transducers survive the bonding process and show distinctly different displacement in response to applied dc bias. Finally, a single-degree-of-freedom model is used to obtain insight into the various contributions to damping. PMID:12699163

  13. Subsurface characterization of an oxidation-induced phase transformation and twinning in nickel-based superalloy exposed to oxy-combustion environments

    SciTech Connect

    Zhu, Jingxi; Holcomb, Gordon R.; Jablonski, Paul D.; Wise, Adam; Li, Jia; Laughlin, David E.; Sridhar, Seetharaman

    2012-07-30

    In the integration of oxy-fuel combustion to turbine power generation system, turbine alloys are exposed to high temperature and an atmosphere comprised of steam, CO{sub 2} and O{sub 2}. While surface and internal oxidation of the alloy takes place, the microstructure in the subsurface region also changes due to oxidation. In this study, bare metal coupons of Ni-base superalloys were exposed in oxy-fuel combustion environment for up to 1000 h and the oxidation-related microstructures were examined. Phase transformation occurred in the subsurface region in Ni-based superalloy and led to twinning. The transformation product phases were analyzed through thermodynamic equilibrium calculations and various electron microscopy techniques, including scanning electron microscopy (SEM), orientation imaging microscopy (OIM) and transmission electron microscopy (TEM). The mechanism by which the phase transformation and the formation of the microstructure occurred was also discussed. The possible effects of the product phases on the performance of the alloy in service were discussed.

  14. Quantitative characterization of chitosan in the skin by Fourier-transform infrared spectroscopic imaging and ninhydrin assay: application in transdermal sciences.

    PubMed

    Nawaz, A; Wong, T W

    2016-07-01

    The chitosan has been used as the primary excipient in transdermal particulate dosage form design. Its distribution pattern across the epidermis and dermis is not easily accessible through chemical assay and limited to radiolabelled molecules via quantitative autoradiography. This study explored Fourier-transform infrared spectroscopy imaging technique with built-in microscope as the means to examine chitosan molecular distribution over epidermis and dermis with the aid of histology operation. Fourier-transform infrared spectroscopy skin imaging was conducted using chitosan of varying molecular weights, deacetylation degrees, particle sizes and zeta potentials, obtained via microwave ligation of polymer chains at solution state. Both skin permeation and retention characteristics of chitosan increased with the use of smaller chitosan molecules with reduced acetyl content and size, and increased positive charge density. The ratio of epidermal to dermal chitosan content decreased with the use of these chitosan molecules as their accumulation in dermis (3.90% to 18.22%) was raised to a greater extent than epidermis (0.62% to 1.92%). A larger dermal chitosan accumulation nonetheless did not promote the transdermal polymer passage more than the epidermal chitosan. A small increase in epidermal chitosan content apparently could fluidize the stratum corneum and was more essential to dictate molecular permeation into dermis and systemic circulation. The histology technique aided Fourier-transform infrared spectroscopy imaging approach introduces a new dimension to the mechanistic aspect of chitosan in transdermal delivery. PMID:26695532

  15. RF transformer

    DOEpatents

    Smith, James L.; Helenberg, Harold W.; Kilsdonk, Dennis J.

    1979-01-01

    There is provided an improved RF transformer having a single-turn secondary of cylindrical shape and a coiled encapsulated primary contained within the secondary. The coil is tapered so that the narrowest separation between the primary and the secondary is at one end of the coil. The encapsulated primary is removable from the secondary so that a variety of different capacity primaries can be utilized with one secondary.

  16. Peculiarities of Determining the Dopant Concentration in the Near-Surface Layer of a Semiconductor by Measuring the Admittance of MIS Structures Based on P-Hg0.78Cd0.22Te Grown by Molecular Beam Epitaxy

    NASA Astrophysics Data System (ADS)

    Voitsekhovskii, A. V.; Nesmelov, S. N.; Dzyadukh, S. M.

    2016-06-01

    Peculiarities of determining the concentration and distribution profile of dopant in the near-surface layer of a semiconductor by measuring the admittance of MIS structures based on p-Hg0.78Cd0.22Te grown by molecular beam epitaxy are studied. A technique is proposed for the determining the concentration of dopant based on the measurement of the admittance of MIS structures in the frequency range of 50 kHz - 1 MHz. It is shown that in this frequency range, the capacitance-voltage characteristics of MIS structures based on p-Hg0.78Cd0.22Te with a near-surface graded-gap layer have a high- frequency behavior with respect to the recharge time of surface states located near the Fermi level of intrinsic semiconductor. The distribution profile of dopant in the nearsurface layer of the semiconductor is calculated. It is shown that in p-Hg0.78Cd0.22Te with a near-surface graded-gap layer, the dopant concentration has the lowest value near the interface with the insulator.

  17. Light-induced catalytic transformation of ofloxacin by solar Fenton in various water matrices at a pilot plant: mineralization and characterization of major intermediate products.

    PubMed

    Michael, I; Hapeshi, E; Aceña, J; Perez, S; Petrović, M; Zapata, A; Barceló, D; Malato, S; Fatta-Kassinos, D

    2013-09-01

    This work investigated the application of a solar driven advanced oxidation process (solar Fenton), for the degradation of the antibiotic ofloxacin (OFX) in various environmental matrices at a pilot-scale. All experiments were carried out in a compound parabolic collector pilot plant in the presence of doses of H2O2 (2.5 mg L(-1)) and at an initial Fe(2+) concentration of 2 mg L(-1). The water matrices used for the solar Fenton experiments were: demineralized water (DW), simulated natural freshwater (SW), simulated effluent from municipal wastewater treatment plant (SWW) and pre-treated real effluent from municipal wastewater treatment plant (RE) to which OFX had been spiked at 10 mg L(-1). Dissolved organic carbon removal was found to be dependent on the chemical composition of the water matrix. OFX mineralization was higher in DW (78.1%) than in SW (58.3%) at 12 mg L(-1) of H2O2 consumption, implying the complexation of iron or the scavenging of hydroxyl radicals by the inorganic ions present in SW. On the other hand, the presence of dissolved organic matter (DOM) in SWW and RE, led to lower mineralization per dose of H2O2 compared to DW and SW. The major transformation products (TPs) formed during the solar Fenton treatment of OFX, were elucidated using liquid chromatography-time of flight-mass spectrometry (LC-ToF-MS). The transformation of OFX proceeded through a defluorination reaction, accompanied by some degree of piperazine and quinolone substituent transformation while a hydroxylation mechanism occurred by attack of the hydroxyl radicals generated during the process leading to the formation of TPs in all the water matrices, seven of which were tentatively identified. The results obtained from the toxicity bioassays indicated that the toxicity originates from the DOM present in RE and its oxidation products formed during the photocatalytic treatment and not from the TPs resulted from the oxidation of OFX. PMID:23712114

  18. Hamlet's Transformation.

    NASA Astrophysics Data System (ADS)

    Usher, P. D.

    1997-12-01

    William Shakespeare's Hamlet has much evidence to suggest that the Bard was aware of the cosmological models of his time, specifically the geocentric bounded Ptolemaic and Tychonic models, and the infinite Diggesian. Moreover, Shakespeare describes how the Ptolemaic model is to be transformed to the Diggesian. Hamlet's "transformation" is the reason that Claudius, who personifies the Ptolemaic model, summons Rosencrantz and Guildenstern, who personify the Tychonic. Pantometria, written by Leonard Digges and his son Thomas in 1571, contains the first technical use of the word "transformation." At age thirty, Thomas Digges went on to propose his Perfit Description, as alluded to in Act Five where Hamlet's age is given as thirty. In Act Five as well, the words "bore" and "arms" refer to Thomas' vocation as muster-master and his scientific interest in ballistics. England's leading astronomer was also the father of the poet whose encomium introduced the First Folio of 1623. His oldest child Dudley became a member of the Virginia Company and facilitated the writing of The Tempest. Taken as a whole, such manifold connections to Thomas Digges support Hotson's contention that Shakespeare knew the Digges family. Rosencrantz and Guildenstern in Hamlet bear Danish names because they personify the Danish model, while the king's name is latinized like that of Claudius Ptolemaeus. The reason Shakespeare anglicized "Amleth" to "Hamlet" was because he saw a parallel between Book Three of Saxo Grammaticus and the eventual triumph of the Diggesian model. But Shakespeare eschewed Book Four, creating this particular ending from an infinity of other possibilities because it "suited his purpose," viz. to celebrate the concept of a boundless universe of stars like the Sun.

  19. TRANSFORMER APPARATUS

    DOEpatents

    Wolfgang, F.; Nicol, J.

    1962-11-01

    Transformer apparatus is designed for measuring the amount of a paramagnetic substance dissolved or suspended in a diamagnetic liquid. The apparatus consists of a cluster of tubes, some of which are closed and have sealed within the diamagnetic substance without any of the paramagnetic material. The remaining tubes are open to flow of the mix- ture. Primary and secondary conductors are wrapped around the tubes in such a way as to cancel noise components and also to produce a differential signal on the secondaries based upon variations of the content of the paramagnetic material. (AEC)

  20. Rotary Transformer

    NASA Technical Reports Server (NTRS)

    McLyman, Colonel Wm. T.

    1996-01-01

    None given. From first Par: Many spacecraft (S/C) and surface rovers require the transfer of signals and power across rotating interfaces. Science instruments, antennas and solar arrays are elements needing rotary power transfer for certain (S/C) configurations. Delivery of signal and power has mainly been done by using the simplest means, the slip ring approach. This approach, although simple, leaves debris generating noise over a period of time...The rotary transformer is a good alternative to slip rings for signal and power transfer.

  1. Corn transformed

    SciTech Connect

    Moffat, A.S.

    1990-08-10

    Researchers have produced fertile corn transformed with a foreign gene that makes the plants resistant to the herbicide bialaphos. This achievement, is the first report of fertile transgenic corn in the reviewed literature, and it is the capstone of almost a decade's efforts to genetically engineer this country's most important crop. The only other major crop to be so manipulated is rice. The ability produce transgenic corn gives biologists a valuable tool to probe the whys and hows of gene expression and regulation. It may also give plant breeders a way to develop new corn varieties with a speed and predictability that would be impossible with classical breeding techniques.

  2. Cloning and characterization of a novel stress-responsive WRKY transcription factor gene (MusaWRKY71) from Musa spp. cv. Karibale Monthan (ABB group) using transformed banana cells.

    PubMed

    Shekhawat, Upendra K Singh; Ganapathi, Thumballi R; Srinivas, Lingam

    2011-08-01

    WRKY transcription factor proteins play significant roles in plant stress responses. Here, we report the cloning and characterization of a novel WRKY gene, MusaWRKY71 isolated from an edible banana cultivar Musa spp. Karibale Monthan (ABB group). MusaWRKY71, initially identified using in silico approaches from an abiotic stress-related EST library, was later extended towards the 3' end using rapid amplification of cDNA ends technique. The 1299-bp long cDNA of MusaWRKY71 encodes a protein with 280 amino acids and contains a characteristic WRKY domain in the C-terminal half. Although MusaWRKY71 shares good similarity with other monocot WRKY proteins the substantial size difference makes it a unique member of the WRKY family in higher plants. The 918-bp long 5' proximal region determined using thermal asymmetric interlaced-polymerase chain reaction has many putative cis-acting elements and transcription factor binding motifs. Subcellular localization assay of MusaWRKY71 performed using a GFP-fusion platform confirmed its nuclear targeting in transformed banana suspension cells. Importantly, MusaWRKY71 expression in banana plantlets was up-regulated manifold by cold, dehydration, salt, ABA, H2O2, ethylene, salicylic acid and methyl jasmonate treatment indicating its involvement in response to a variety of stress conditions in banana. Further, transient overexpression of MusaWRKY71 in transformed banana cells led to the induction of several genes, homologues of which have been proven to be involved in diverse stress responses in other important plants. The present study is the first report on characterization of a banana stress-related transcription factor using transformed banana cells. PMID:21110110

  3. Transformational leadership.

    PubMed

    Marlow, D L

    1996-01-01

    In these uncertain times in the healthcare industry, administrators are asked to do more with less time and resources. Because of the extended roles they are playing in today's organizations, radiology administrators are looked upon as agents of change. What leadership skills do they need in this turbulent and uncertain healthcare environment? What are the trait's of tomorrow's leaders? The transformational leader is the one who will guide us through this changing healthcare environment. Several behavioral patterns emerge as important traits for tomorrow's leaders to have-individual consideration, intellectual stimulation and charisma. Tomorrow's leader must view each person as an individual, showing genuine concern and belief in each person's ability to perform. Transformational leaders stimulate others by encouraging them to be curious and try new ideas. The final characteristic, charisma, is the ability to inspire others. Luckily, leaders are made, not born: today's leaders can learn to be responsive, to draw out new ideas from employees, and to communicate self-esteem, energy and enthusiasm. PMID:10163135

  4. Expression and Functional Characterization of the Agrobacterium VirB2 Amino Acid Substitution Variants in T-pilus Biogenesis, Virulence, and Transient Transformation Efficiency

    PubMed Central

    Wu, Hung-Yi; Chen, Chao-Ying; Lai, Erh-Min

    2014-01-01

    Agrobacterium tumefaciens is a phytopathogenic bacterium that causes crown gall disease by transferring transferred DNA (T-DNA) into the plant genome. The translocation process is mediated by the type IV secretion system (T4SS) consisting of the VirD4 coupling protein and 11 VirB proteins (VirB1 to VirB11). All VirB proteins are required for the production of T-pilus, which consists of processed VirB2 (T-pilin) and VirB5 as major and minor subunits, respectively. VirB2 is an essential component of T4SS, but the roles of VirB2 and the assembled T-pilus in Agrobacterium virulence and the T-DNA transfer process remain unknown. Here, we generated 34 VirB2 amino acid substitution variants to study the functions of VirB2 involved in VirB2 stability, extracellular VirB2/T-pilus production and virulence of A. tumefaciens. From the capacity for extracellular VirB2 production (ExB2+ or ExB2−) and tumorigenesis on tomato stems (Vir+ or Vir−), the mutants could be classified into three groups: ExB2−/Vir−, ExB2−/Vir+, and ExB2+/Vir+. We also confirmed by electron microscopy that five ExB2−/Vir+ mutants exhibited a wild-type level of virulence with their deficiency in T-pilus formation. Interestingly, although the five T-pilus−/Vir+ uncoupling mutants retained a wild-type level of tumorigenesis efficiency on tomato stems and/or potato tuber discs, their transient transformation efficiency in Arabidopsis seedlings was highly attenuated. In conclusion, we have provided evidence for a role of T-pilus in Agrobacterium transformation process and have identified the domains and amino acid residues critical for VirB2 stability, T-pilus biogenesis, tumorigenesis, and transient transformation efficiency. PMID:24971727

  5. Characterization of Japanese color sticks by energy dispersive X-ray fluorescence, X-ray diffraction and Fourier transform infrared analysis

    NASA Astrophysics Data System (ADS)

    Manso, M.; Valadas, S.; Pessanha, S.; Guilherme, A.; Queralt, I.; Candeias, A. E.; Carvalho, M. L.

    2010-04-01

    This work comprises the use of energy dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) techniques for the study of the composition of twentieth century traditional Japanese color sticks. By using the combination of analytical techniques it was possible to obtain information on inorganic and organic pigments, binders and fillers present in the sticks. The colorant materials identified in the sticks were zinc and titanium white, chrome yellow, yellow and red ochre, vermillion, alizarin, indigo, Prussian and synthetic ultramarine blue. The results also showed that calcite and barite were used as inorganic mineral fillers while Arabic gum was the medium used. EDXRF offered great potential for such investigations since it allowed the identification of the elements present in the sample preserving its integrity. However, this information alone was not enough to clearly identify some of the materials in study and therefore it was necessary to use XRD and FTIR techniques.

  6. Characterization of ancient glass excavated in Enez (Ancient Ainos) Turkey by combined Instrumental Neutron Activation Analysis and Fourier Transform Infrared spectrometry techniques

    NASA Astrophysics Data System (ADS)

    Akyuz, Sevim; Akyuz, Tanil; Mukhamedshina, Nuranya M.; Mirsagatova, A. Adiba; Basaran, Sait; Cakan, Banu

    2012-05-01

    Ancient glass fragments excavated in the archaeological district Enez (Ancient Ainos)-Turkey were investigated by combined Instrumental Neutron Activation Analysis (INAA) and Fourier Transform Infrared (FTIR) spectrometry techniques. Multi-elemental contents of 15 glass fragments that belong to Hellenistic, Roman, Byzantine, and Ottoman Periods, were determined by INAA. The concentrations of twenty six elements (Na, K, Ca, Sc, Cr, Mn, Fe, Co, Cu, Zn, As, Rb, Sr, Sb, Cs, Ba, Ce, Sm, Eu, Tb, Yb, Lu, Hf, Ta, Au and Th), which might be present in the samples as flux, stabilizers, colorants or opacifiers, and impurities, were examined. Chemometric treatment of the INAA data was performed and principle component analysis revealed presence of 3 distinct groups. The thermal history of the glass samples was determined by FTIR spectrometry.

  7. Characterization of cancer stem-like cells derived from mouse induced pluripotent stem cells transformed by tumor-derived extracellular vesicles.

    PubMed

    Yan, Ting; Mizutani, Akifumi; Chen, Ling; Takaki, Mai; Hiramoto, Yuki; Matsuda, Shuichi; Shigehiro, Tsukasa; Kasai, Tomonari; Kudoh, Takayuki; Murakami, Hiroshi; Masuda, Junko; Hendrix, Mary J C; Strizzi, Luigi; Salomon, David S; Fu, Li; Seno, Masaharu

    2014-01-01

    Several studies have shown that cancer niche can perform an active role in the regulation of tumor cell maintenance and progression through extracellular vesicles-based intercellular communication. However, it has not been reported whether this vesicle-mediated communication affects the malignant transformation of normal stem cells/progenitors. We have previously reported that the conditioned medium derived from the mouse Lewis Lung Carcinoma (LLC) cell line can convert mouse induced pluripotent stem cells (miPSCs) into cancer stem cells (CSCs), indicating that normal stem cells when placed in an aberrant microenvironment can give rise to functionally active CSCs. Here, we focused on the contribution of tumor-derived extracellular vesicles (tEVs) that are secreted from LLC cells to induce the transformation of miPSCs into CSCs. We isolated tEVs from the conditioned medium of LLC cells, and then the differentiating miPSCs were exposed to tEVs for 4 weeks. The resultant tEV treated cells (miPS-LLCev) expressed Nanog and Oct3/4 proteins comparable to miPSCs. The frequency of sphere formation of the miPS-LLCev cells in suspension culture indicated that the self-renewal capacity of the miPS-LLCev cells was significant. When the miPS-LLCev cells were subcutaneously transplanted into Balb/c nude mice, malignant liposarcomas with extensive angiogenesis developed. miPS-LLCevPT and miPS-LLCevDT, the cells established from primary site and disseminated liposarcomas, respectively, showed their capacities to self-renew and differentiate into adipocytes and endothelial cells. Moreover, we confirmed the secondary liposarcoma development when these cells were transplanted. Taken together, these results indicate that miPS-LLCev cells possess CSC properties. Thus, our current study provides the first evidence that tEVs have the potential to induce CSC properties in normal tissue stem cells/progenitors. PMID:25057308

  8. Characterization of Cancer Stem-Like Cells Derived from Mouse Induced Pluripotent Stem Cells Transformed by Tumor-Derived Extracellular Vesicles

    PubMed Central

    Yan, Ting; Mizutani, Akifumi; Chen, Ling; Takaki, Mai; Hiramoto, Yuki; Matsuda, Shuichi; Shigehiro, Tsukasa; Kasai, Tomonari; Kudoh, Takayuki; Murakami, Hiroshi; Masuda, Junko; Hendrix, Mary J. C.; Strizzi, Luigi; Salomon, David S.; Fu, Li; Seno, Masaharu

    2014-01-01

    Several studies have shown that cancer niche can perform an active role in the regulation of tumor cell maintenance and progression through extracellular vesicles-based intercellular communication. However, it has not been reported whether this vesicle-mediated communication affects the malignant transformation of normal stem cells/progenitors. We have previously reported that the conditioned medium derived from the mouse Lewis Lung Carcinoma (LLC) cell line can convert mouse induced pluripotent stem cells (miPSCs) into cancer stem cells (CSCs), indicating that normal stem cells when placed in an aberrant microenvironment can give rise to functionally active CSCs. Here, we focused on the contribution of tumor-derived extracellular vesicles (tEVs) that are secreted from LLC cells to induce the transformation of miPSCs into CSCs. We isolated tEVs from the conditioned medium of LLC cells, and then the differentiating miPSCs were exposed to tEVs for 4 weeks. The resultant tEV treated cells (miPS-LLCev) expressed Nanog and Oct3/4 proteins comparable to miPSCs. The frequency of sphere formation of the miPS-LLCev cells in suspension culture indicated that the self-renewal capacity of the miPS-LLCev cells was significant. When the miPS-LLCev cells were subcutaneously transplanted into Balb/c nude mice, malignant liposarcomas with extensive angiogenesis developed. miPS-LLCevPT and miPS-LLCevDT, the cells established from primary site and disseminated liposarcomas, respectively, showed their capacities to self-renew and differentiate into adipocytes and endothelial cells. Moreover, we confirmed the secondary liposarcoma development when these cells were transplanted. Taken together, these results indicate that miPS-LLCev cells possess CSC properties. Thus, our current study provides the first evidence that tEVs have the potential to induce CSC properties in normal tissue stem cells/progenitors. PMID:25057308

  9. Use of wavelet-packet transforms to develop an engineering model for multifractal characterization of mutation dynamics in pathological and nonpathological gene sequences

    NASA Astrophysics Data System (ADS)

    Walker, David Lee

    1999-12-01

    This study uses dynamical analysis to examine in a quantitative fashion the information coding mechanism in DNA sequences. This exceeds the simple dichotomy of either modeling the mechanism by comparing DNA sequence walks as Fractal Brownian Motion (fbm) processes. The 2-D mappings of the DNA sequences for this research are from Iterated Function System (IFS) (Also known as the ``Chaos Game Representation'' (CGR)) mappings of the DNA sequences. This technique converts a 1-D sequence into a 2-D representation that preserves subsequence structure and provides a visual representation. The second step of this analysis involves the application of Wavelet Packet Transforms, a recently developed technique from the field of signal processing. A multi-fractal model is built by using wavelet transforms to estimate the Hurst exponent, H. The Hurst exponent is a non-parametric measurement of the dynamism of a system. This procedure is used to evaluate gene- coding events in the DNA sequence of cystic fibrosis mutations. The H exponent is calculated for various mutation sites in this gene. The results of this study indicate the presence of anti-persistent, random walks and persistent ``sub-periods'' in the sequence. This indicates the hypothesis of a multi-fractal model of DNA information encoding warrants further consideration. This work examines the model's behavior in both pathological (mutations) and non-pathological (healthy) base pair sequences of the cystic fibrosis gene. These mutations both natural and synthetic were introduced by computer manipulation of the original base pair text files. The results show that disease severity and system ``information dynamics'' correlate. These results have implications for genetic engineering as well as in mathematical biology. They suggest that there is scope for more multi-fractal models to be developed.

  10. Herbicide Transformation

    PubMed Central

    Lanzilotta, R. P.; Pramer, David

    1970-01-01

    A strain of Fusarium solani isolated from soil by enrichment techniques used propanil (3′, 4′-dichloropropionanilide) as a sole source of organic carbon and energy for growth in pure culture. The primary product of the transformation of propanil by F. solani was isolated and identified as 3,4-dichloroaniline (DCA). This compound accumulated in the medium to a level (80 μg/ml) which stopped further herbicide utilization. Herbicide utilization by F. solani was influenced by various environmental and nutritional factors. It was more sensitive to acid than alkaline pH. Added glucose and yeast extract increased the rate of propanil decomposition, and the reduced aeration retarded growth of the fungus and herbicide utilization. The growth of F. solani on propionate was inhibited by added DCA. Images PMID:5437305

  11. Genesis of a Cerium Oxide-Supported Gold Catalyst for CO Oxidation: Transformation of Mononuclear Gold Complexes into Clusters as Characterized by X-Ray Absorption Spectroscopy

    SciTech Connect

    Aguilar-Guerrero, V.; Lobo-Lapidus, R; Gates, B

    2009-01-01

    CeO{sub 2}-supported mononuclear gold species synthesized from Au(CH{sub 3}){sub 2}(acac) catalyzed CO oxidation at 353 K, with a turnover frequency of 6.5 x 10{sup -3} molecules of CO (Au atom s){sup -1} at CO and O{sub 2} partial pressures of 1.0 and 0.5 kPa, respectively. As the catalyst functioned in a flow reactor, the activity increased markedly so that within about 10 h the conversion of CO had increased from about 1% to almost 100%. Activated catalyst samples were characterized by X-ray absorption spectroscopy and found to incorporate clusters of gold, which increased in size, undergoing reduction, with increasing time of operation. The X-ray absorption near-edge structure spectrum of the catalyst used for the longest period was indistinguishable from that characterizing gold foil. Extended X-ray absorption fine structure data characterizing the catalyst after the longest period of operation indicated the presence of clusters of approximately 30 Au atoms each, on average. The evidence that the catalytic activity increased as the clusters grew is contrasted with earlier reports pointing to increasing activity of supported gold clusters as they were made smallerin a cluster size range largely exceeding ours.

  12. Polycyclic aromatic hydrocarbons (PAHs) in ambient aerosols from Beijing: characterization of low volatile PAHs by positive-ion atmospheric pressure photoionization (APPI) coupled with Fourier transform ion cyclotron resonance.

    PubMed

    Jiang, Bin; Liang, Yongmei; Xu, Chunming; Zhang, Jingyi; Hu, Miao; Shi, Quan

    2014-05-01

    Aromatic fractions derived from aerosol samples were characterized by gas chromatography and mass spectrometry (GC-MS), high temperature simulated distillation (SIMDIS), and positive-ion atmospheric pressure photoionization (APPI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), respectively. It was found that about 27 wt % compounds in aromatic fractions could not be eluted from a GC column and some large molecule PAHs were neglected in GC-MS analysis. APPI FT-ICR MS was proven to be a powerful approach for characterizing the molecular composition of aromatics, especially for the large molecular species. An aromatic sample from Beijing urban aerosol was successfully characterized by APPI FT-ICR MS. Results showed that most abundant aromatic compounds in PM2.5 (particles with aerodynamic diameter ≤ 2.5 μm) were highly condensed hydrocarbons with 4-8 aromatic rings and their homologues with very short alkyl chains. Furthermore, heteroatom-containing hydrocarbons were found as the significant components of the aromatic fractions: O1, O2, N1, and S1 class species with 10-28 DBEs (double bond equivalents) and 14-38 carbon numbers were identified by APPI FT-ICR MS. The heteroatom PAHs had similar DBEs and carbon number distribution as regular PAHs. PMID:24702199

  13. Identification and Characterization of a Ginsenoside-Transforming β-Glucosidase from Pseudonocardia sp. Gsoil 1536 and Its Application for Enhanced Production of Minor Ginsenoside Rg2(S)

    PubMed Central

    Park, Sung Chul; Kim, Jin-Kwang; Yu, Hong-Shan; Jin, Feng-Xie; Sun, Changkai; Kim, Sun-Chang; Im, Wan-Taek

    2014-01-01

    The ginsenoside Rg2(S), which is one of the pharmaceutical components of ginseng, is known to have neuroprotective, anti-inflammation, and anti-diabetic effects. However, the usage of ginsenoside Rg2(S) is restricted owing to the small amounts found in white and red ginseng. To enhance the production of ginsenoside Rg2(S) as a 100 gram unit with high specificity, yield, and purity, an enzymatic bioconversion method was developed to adopt the recombinant glycoside hydrolase (BglPC28), which is a ginsenoside-transforming recombinant β-glucosidase from Pseudonocardia sp. strain Gsoil 1536. The gene, termed bglPC28, encoding β-glucosidase (BglPC28) belonging to the glycoside hydrolase family 3 was cloned. bglPC28 consists of 2,232 bp (743 amino acid residues) with a predicted molecular mass of 78,975 Da. This enzyme was overexpressed in Escherichia coli BL21(DE3) using a GST-fused pGEX 4T-1 vector system. The optimum conditions of the recombinant BglPC28 were pH 7.0 and 37°C. BglPC28 can effectively transform the ginsenoside Re to Rg2(S); the Km values of PNPG and Re were 6.36±1.10 and 1.42±0.13 mM, respectively, and the Vmax values were 40.0±2.55 and 5.62±0.21 µmol min−1 mg−1 of protein, respectively. A scaled-up biotransformation reaction was performed in a 10 L jar fermenter at pH 7.0 and 30°C for 12 hours with a concentration of 20 mg/ml of ginsenoside Re from American ginseng roots. Finally, 113 g of Rg2(S) was produced from 150 g of Re with 84.0±1.1% chromatographic purity. These results suggest that this enzymatic method could be usefully exploited in the preparation of ginsenoside Rg2(S) in the cosmetics, functional food, and pharmaceutical industries. PMID:24911166

  14. Fourier transform infrared spectroscopy and chemometrics for the characterization and discrimination of writing/photocopier paper types: Application in forensic document examinations.

    PubMed

    Kumar, Raj; Kumar, Vinay; Sharma, Vishal

    2017-01-01

    The aim of the present work is to explore the non-destructive application of ATR-FTIR technique for characterization and discrimination of paper samples which could be helpful to give forensic aid in resolving legal cases. Twenty-four types of paper brands were purchased from local market in and around Chandigarh, India. All the paper samples were subjected to ATR-FTIR analysis from 400 to 4000cm(-1) wavenumber range. The qualitative feature and Chemometrics of the obtained spectral data are used for characterization and discrimination. Characterization is achieved by matching the peaks with standards of cellulose and inorganic fillers, a usual constituents of paper. Three different regions of IR, i.e. 400-2000cm(-1), 2000-4000cm(-1) and 400-4000cm(-1) were selected for differentiation by Chemometrics analysis. The discrimination is achieved on the basis of three principal components, i.e. PC 1, PC 2 and PC 3. It is observed that maximum discrimination was procured in the wave number range of i.e. 2000-4000cm(-1). Discriminating power was calculated on the basis of qualitative features as well, and it is found that the discrimination of paper samples was better achieved by Chemometrics analysis rather than qualitative features. The discriminating power by Chemometrics is 99.64% and which is larger as ever achieved by any group for present number of samples. The present result confirms that this study will be highly useful in forensic document examination work in the legal cases, where the authenticity of the document is challenged. The results are completely analytical and, therefore, overcome the problem encounter in traditional routine light/radiation scanning methods which are still in practice by various questioned document laboratories. PMID:27394012

  15. In situ Fourier transform infrared characterization of sulfur species resulting from the reaction of water vapor and oxygen with zinc sulfide

    SciTech Connect

    Siriwardane, R.V.; Woodruff, S.

    1997-12-01

    Steam is utilized as a diluent in the regeneration of zinc-based hot gas desulfurization sorbents used in fuel gas cleanup. Therefore, the effect of water vapor on the interaction of zinc sulfide (ZnS) with oxygen at 823, 873, and 923 K was studied using Fourier transform infrared (FTIR) spectroscopy. When ZnS at 823 K was exposed to oxygen, sulfate (SO{sub 4}{sup 2{minus}}) was the most prominent species observed at oxygen pressures greater than 5 {times} 10{sup {minus}2} Torr while sulfite (SO{sub 3}{sup 2{minus}}) was the major species observed during the water vapor exposures. When ZnS at 823 K was exposed to an equimolar mixture of water vapor and oxygen, sulfite and sulfate were the most prominent products but the intensity of the sulfite peak was more than that of the sulfate. The sulfur species formed during the water vapor and oxygen exposures at both 873 and 923 K were similar to those at 823 K, but the relative intensities of the peaks corresponding to these sulfur species were different. At all three temperatures, the presence of water vapor enhanced the formation of sulfite, which can be decomposed more readily than sulfate. Thus, it is hypothesized that it would be desirable to have water vapor present during the regeneration of ZnS to form ZnO.

  16. The Use of Accurate Mass Tags based upon High-Throughput Fourier Transform Ion Cyclotron Resonance Mass Spectrometry for Global Proteomic Characterization

    SciTech Connect

    Camp, David G.; Smith, Richard D.

    2004-07-30

    In this review, we describe the technological basis and progress towards a new global proteomics strategy that uses peptide accurate mass measurements augmented by information from separations (e.g. LC retention times) to provide large improvements in sensitivity, dynamic range, comprehensiveness and throughput. The use of ?accurate mass and time? (AMT) tags serves to eliminate the need for routine MS/MS measurements [#4109]. As the case study, we use our own research efforts to illustrate the role of AMTs within the broader context of a state-of-the-art proteomics effort. Our strategy exploits high-resolution capillary LC separations combined with Fourier transform ion cyclotron resonance mass spectrometry (FTICR). AMTs represent peptide biomarkers and can be used to confidently identify proteins based on the high mass measurement accuracy provided by FTICR combined with LC elution times. Once identified using MS/MS, these biomarkers provide the foundation for subsequent high throughput studies using only AMT tags to identify and quantify the proteins expressed within a cell system. Key attractions of this approach include the feasibility of completely automated high confidence protein identifications, extensive proteome coverage, and the capability for exploiting stable-isotope labeling methods for high precision abundance measurements [#4019]. Additional developments described in this review include methods for more effective coverage of membrane proteins [#4184], for dynamic range expansion of proteome measurements [#4012], and for multi-stage separations that promise to enable more focused analyses, further extend the quality of measurements, and also extend measurements to more complex proteomes.

  17. Characterization of beta-lactoglobulin fibrillar assembly using atomic force microscopy, polyacrylamide gel electrophoresis, and in situ fourier transform infrared spectroscopy.

    PubMed

    Oboroceanu, Daniela; Wang, Lizhe; Brodkorb, André; Magner, Edmond; Auty, Mark A E

    2010-03-24

    The aggregation process of beta-lactoglobulin (beta-lg) from 0 min to 20 h was studied using atomic force microscopy (AFM), scanning transmission electron microscopy (STEM), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and in situ attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). Fibril assembly was monitored in real time using AFM up to 20 h. From 0 to 85 min, beta-lg monomers deformed and expanded with some aggregation. After 85 min, fibrillar structures were formed, exceeding 10 mum in length. Fibrillar structures were confirmed by STEM. Secondary structural changes occurring during fibril formation were monitored by ATR-FTIR at 80 degrees C and indicated a decrease in alpha-helix content and an increase in beta-sheet content. SDS-PAGE indicated that fibrils were composed of polypeptides and not intact monomers. In this study, beta-lg and whey protein isolate (WPI)-derived fibrils, including some double helices, in water were observed by AFM under ambient conditions and in their native aqueous environment. PMID:20187607

  18. Phase transformations coupled to deformation processes

    NASA Astrophysics Data System (ADS)

    Lookman, Turab

    2013-06-01

    Phase transformation processes have a substantial impact on the inelastic and damage response of materials. Yet, our understanding of how different loading conditions affect volume fractions of transformed phases, microstructure and transformation pathways is very much in its infancy. With an emphasis on distilling single crystal physics that can, in principle, be incorporated into higher length scale models, I will discuss how recent atomistic simulations on Ti are beginning to provide insights into transformation pathways and the interplay of phase transformations and deformation processes. These simulations are complemented by shock experiments on Zr, Ti together with characterization studies at the Advanced Photon Source.

  19. Broadband Planar 5:1 Impedence Transformer

    NASA Technical Reports Server (NTRS)

    Ehsan, Negar; Hsieh, Wen-Ting; Moseley, Samuel H.; Wollack, Edward J.

    2015-01-01

    This paper presents a broadband Guanella-type planar impedance transformer that transforms so 50 omega to 10 omega with a 10 dB bandwidth of 1-14GHz. The transformer is designed on a flexible 50 micrometer thick polyimide substrate in microstrip and parallel-plate transmission line topologies, and is Inspired by the traditional 4:1 Guanella transformer. Back-to-back transformers were designed and fabricated for characterization in a 50 omega system. Simulated and measured results are in excellent agreement.

  20. Mn(II)- and Co(II)-Catalyzed Transformation of 2-Cyanopyrimidine to Methylimidate by Sodium Azide: Isolation, Structural Characterization, and Magnetic Studies on 2D Mn(II)- and Cu(II)-Complexes.

    PubMed

    Dolai, Malay; Biswas, Surajit; Escuer, Albert; Ali, Mahammad

    2015-07-20

    The Mn(II)-mediated transformation of 2-cyanopyrimidine to methylimidate in the presence of inorganic azide is proven through isolation and structural characterization of a metal complex. Though the reaction conditions are favorable for a "click" reaction leading to the formation of tetrazole, as evidenced from recent studies, we are astonished to see the formation of methylimidate in MeOH instead of tetrazole, which is supposed to form only in the presence of catalytic amount of corresponding alkoxide ion as base. The catalytic nature of this transformation reaction was confirmed by performing these experiments under catalytic conditions and analyzing the products using liquid chromatography-mass spectrometry techniques, which clearly showed ∼96% and ∼60% selectivity of methylimidate along with almost 100% conversion in the presence of Mn(II) and Co(II) as catalysts, respectively. In absence or presence of other metal ions like Cu(II), Ni(II), Fe(II), Zn(II), etc. only tetrazole formation takes place. So the present findings extended the formation of methylimidate catalyzed by metal ions in the presence of azide ion in alcoholic medium. Importantly, a probable mechanism for this unexpected transformation was framed based on the structural analysis and high-resolution mass spectrometry (electrospray ionization MS(+)) studies. The magnetic studies were also performed on complexes [Mn(L)(N3)2]n (1) and [Cu (L(2))2]n (2a), showing anti-ferromagnetic character for compound 1 and negligible coupling for the copper complex 2a. PMID:26135905

  1. General linear chirplet transform

    NASA Astrophysics Data System (ADS)

    Yu, Gang; Zhou, Yiqi

    2016-03-01

    Time-frequency (TF) analysis (TFA) method is an effective tool to characterize the time-varying feature of a signal, which has drawn many attentions in a fairly long period. With the development of TFA, many advanced methods are proposed, which can provide more precise TF results. However, some restrictions are introduced inevitably. In this paper, we introduce a novel TFA method, termed as general linear chirplet transform (GLCT), which can overcome some limitations existed in current TFA methods. In numerical and experimental validations, by comparing with current TFA methods, some advantages of GLCT are demonstrated, which consist of well-characterizing the signal of multi-component with distinct non-linear features, being independent to the mathematical model and initial TFA method, allowing for the reconstruction of the interested component, and being non-sensitivity to noise.

  2. Characterization by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry of the major photoproducts of temoporfin (m-THPC) and bacteriochlorin (m-THPBC).

    PubMed

    Angotti, M; Maunit, B; Muller, J F; Bezdetnaya, L; Guillemin, F

    2001-07-01

    The photobleaching of 5,10,15,20-tetrakis(m-hydroxyphenyl)chlorin (temoporfin, m-THPC) and 5,10,15,20-tetrakis(m-hydroxyphenyl)bacteriochlorin (bacteriochlorin, m-THPBC) was studied in ethanol-water (1 : 99, v/v) and in physiological medium (phosphate-buffered saline, PBS) with or without fetal calf serum (FCS). m-THPC solution was irradiated with the laser radiation of 650 nm, whereas m-THPBC solution underwent two consecutive irradiations at 532 and 650 nm. The photoproducts were characterized by UV-visible absorption spectrophotometry and by matrix-assisted laser desorption/ionization (MALDI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS). Independent of the solvent used, the phototransformation of either photosensitizer yielded the formation of 5,10,15,20-tetrakis (m-hydroxyphenyl)porphyrin (m-THPP) through a major dehydrogenation process. PMID:11473406

  3. Special Features of Admittance in Mis Structures Based on Graded-Gap MBE n-Hg1- x Cd x Te ( x = 0.31-0.32) in a Temperature Range OF 8-300 K

    NASA Astrophysics Data System (ADS)

    Voitsekhovskii, A. V.; Nesmelov, S. N.; Dzyadukh, S. M.; Vasil'ev, V. V.; Varavin, V. S.; Dvoretskii, S. A.; Mikhailov, N. N.; Kuz'min, V. D.; Remesnik, V. G.

    2014-09-01

    Admittance of MIS structures based on graded-gap n-Hg1- х Cd х Te ( x = 0.31-0.32) grown by molecular beam epitaxy (MBE) is investigated in a wide temperature range (8-300 K). It is shown that the temperature and frequency dependences of the differential resistance of space charge region for structures with a graded-gap layer are qualitatively similar to those for structures without a graded-gap layer. It is found that for MIS structures based on MBE n-Hg1- х Cd х Te ( x = 0.31-0.32), regardless of the presence of a graded-gap layer, the differential resistance of space charge region is limited by the processes of Shockley-Read generation in the temperature range of 25-100 K.

  4. Characterization of the Adsorption of Nucleic Acid Bases onto Ferrihydrite via Fourier Transform Infrared and Surface-Enhanced Raman Spectroscopy and X-ray Diffractometry.

    PubMed

    Canhisares-Filho, José E; Carneiro, Cristine E A; de Santana, Henrique; Urbano, Alexandre; da Costa, Antonio C S; Zaia, Cássia T B V; Zaia, Dimas A M

    2015-09-01

    Minerals could have played an important role in concentration, protection, and polymerization of biomolecules. Although iron is the fourth most abundant element in Earth's crust, there are few works in the literature that describe the use of iron oxide-hydroxide in prebiotic chemistry experiments. In the present work, the interaction of adenine, thymine, and uracil with ferrihydrite was studied under conditions that resemble those of prebiotic Earth. At acidic pH, anions in artificial seawater decreased the pH at the point of zero charge (pHpzc) of ferrihydrite; and at basic pH, cations increased the pHpzc. The adsorption of nucleic acid bases onto ferrihydrite followed the order adenine > uracil > thymine. Adenine adsorption peaked at neutral pH; however, for thymine and uracil, adsorption increased with increasing pH. Electrostatic interactions did not appear to play an important role on the adsorption of nucleic acid bases onto ferrihydrite. Adenine adsorption onto ferrihydrite was higher in distilled water compared to artificial seawater. After ferrihydrite was mixed with artificial seawaters or nucleic acid bases, X-ray diffractograms and Fourier transform infrared spectra did not show any change. Surface-enhanced Raman spectroscopy showed that the interaction of adenine with ferrihydrite was not pH-dependent. In contrast, the interactions of thymine and uracil with ferrihydrite were pH-dependent such that, at basic pH, thymine and uracil lay flat on the surface of ferrihydrite, and at acidic pH, thymine and uracil were perpendicular to the surface. Ferrihydrite adsorbed much more adenine than thymine; thus adenine would have been better protected against degradation by hydrolysis or UV radiation on prebiotic Earth. PMID:26393397

  5. Reactivity and chemical characterization of effluent organic nitrogen from wastewater treatment plants determined by Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Mesfioui, Rajaa; Love, Nancy G; Bronk, Deborah A; Mulholland, Margaret R; Hatcher, Patrick G

    2012-03-01

    In advanced wastewater treatment plants that achieve high levels of nitrogen (N) removal, up to one-third of the N in effluent is organic, herein referred to as effluent organic N (EON). While we know that inorganic N is highly labile, it is unclear what fraction of EON is bioavailable. In this study, we demonstrate the utility of a method that can be used to examine the reactivity of EON in natural receiving waters to better understand both the ecosystem response and the potential bioavailability of EON. The technique is suitable for analyzing polar organic matter in natural waters; electrospray ionization coupled with Fourier transform mass spectrometry. Bioassays were performed on samples collected at the end of the biological process from two wastewater treatment plants achieving advanced N removal. The samples were concentrated, and then added to natural water samples collected from the oligohaline James River, a major tributary of the Chesapeake Bay. Our results demonstrate that while the lignin-like fraction of the effluent dissolved organic matter (some of which contains N) was conserved, a large portion of aliphatic and aromatic compounds containing N was removed (79-100%) during incubations, while other compounds were produced. Furthermore, the two effluents exhibited differences in the degree of degradation and type of degradation, which can be related both to the various processes employed in the two WWTPs and the dramatic differences in the type of influent they received. These findings suggest that EON is highly reactive in the natural environment and that simple assays examining net consumption or production of bulk dissolved organic N pools are inadequate for assessing the bioavailability of EON. PMID:22172558

  6. ATMOSPHERIC TRANSFORMATION OF DIESEL EMISSIONS

    EPA Science Inventory

    The investigators anticipate successfully conducting a complex study to characterize the atmospheric transformations of DE under the influence of sunlight, O3, radicals, and organic compounds. It is hope that this study will present novel results on the atmospheric aging of...

  7. Evaluate and characterize mechanisms controlling transport, fate, and effects of army smokes in the aerosol wind tunnel: Transport, transformations, fate, and terrestrial ecological effects of hexachloroethane obscurant smokes

    SciTech Connect

    Cataldo, D.A.; Ligotke, M.W.; Bolton, H. Jr.; Fellows, R.J.; Van Voris, P.; McVeety, B.D.; Li, Shu-mei W.; McFadden, K.M.

    1989-09-01

    The terrestrial transport, chemical fate, and ecological effects of hexachloroethane (HC) smoke were evaluated under controlled wind tunnel conditions. The primary objectives of this research program are to characterize and assess the impacts of smoke and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of soils representative of these training sites; and (3) soil microbiological and invertebrate communities. Impacts and dose/responses were evaluated based on exposure scenarios, including exposure duration, exposure rate, and sequential cumulative dosing. Key to understanding the environmental impacts of HC smoke/obscurants is establishing the importance of environmental parameters such as relative humidity and wind speed on airborne aerosol characteristics and deposition to receptor surfaces. Direct and indirect biotic effects were evaluated using five plant species and two soil types. HC aerosols were generated in a controlled atmosphere wind tunnel by combustion of hexachloroethane mixtures prepared to simulate normal pot burn rates and conditions. The aerosol was characterized and used to expose plant, soil, and other test systems. Particle sizes of airborne HC ranged from 1.3 to 2.1 {mu}m mass median aerodynamic diameter (MMAD), and particle size was affected by relative humidity over a range of 20% to 85%. Air concentrations employed ranged from 130 to 680 mg/m{sup 3}, depending on exposure scenario. Chlorocarbon concentrations within smokes, deposition rates for plant and soil surfaces, and persistence were determined. The fate of principal inorganic species (Zn, Al, and Cl) in a range of soils was assessed.

  8. Identification and characterization of transforming growth factor β-activated kinase 1 from Litopenaeus vannamei involved in anti-bacterial host defense.

    PubMed

    Wang, Sheng; Li, Haoyang; L, Kai; Qian, Zhe; Weng, Shaoping; He, Jianguo; Li, Chaozheng

    2016-05-01

    LvTAK1, a member of transforming growth factor β-activated kinase 1 (TAK1) families, has been identified from Litopenaeus vannamei in this study. The full length of LvTAK1 is 2670 bp, including a 2277 bp open reading frame (ORF) that encoded a putative protein of 758 amino acids with a calculated molecular weight of ∼83.4 kDa LvTAK1 expression was most abundant in muscles and was up-regulated in gills after LPS, Vibrio parahaemolyticus, Staphhylococcu saureus, Poly (I:C) and WSSV challenge. Both in vivo and in vitro experiments indicated that LvTAK1 could activate the expression of several antimicrobial peptide genes (AMPs). In addition, the dsRNA-mediated knockdown of LvTAK1 enhanced the susceptibility of shrimps to Vibrio parahaemolyticus, a kind of Gram-negative bacteria. These results suggested LvTAK1 played important roles in anti-bacterial infection. CoIP and subcellular localization assay demonstrated that LvTAK1 could interact with its binding protein LvTAB2, a key component of IMD pathway. Moreover, over-expression of LvTAK1 in Drosophila S2 cell could strongly induce the promoter activity of Diptericin (Dpt), a typical AMP which is used to read out of the activation of IMD pathway. These findings suggested that LvTAK1 could function as a component of IMD pathway. Interestingly, with the over-expression of LvTAK1 in S2 cell, the promoter activity of Metchnikowin (Mtk), a main target gene of Toll/Dif pathway, was up-regulated over 30 times, suggesting that LvTAK1 may also take part in signal transduction of the Toll pathway. In conclusion, we provided some evidences that the involvement of LvTAK1 in the regulation of both Toll and IMD pathways, as well as innate immune against bacterial infection in shrimp. PMID:27033469

  9. Molecular Characterization and Reactivity of Dissolved Organic Matter by High Resolution Nanospray Ionization Fourier Transform-Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS)

    NASA Astrophysics Data System (ADS)

    Sleighter, R. L.; Hatcher, S. A.; Hatcher, P. G.

    2006-12-01

    The ultrahigh resolving power of FTICR-MS allows for the intense characterization of dissolved organic matter (DOM). DOM is the largest reactive component of the global carbon cycle, and an improved understanding of its composition is necessary to determine the transport and eventual fate of pollutants. The seasonal and spatial variations in DOM composition are investigated by taking surface water samples from five different sampling sites, four times a year. Water sampling begins at the Dismal Swamp in North Carolina, continues north up the Elizabeth River to the Chesapeake Bay, and concludes approximately ten miles off the coast in the Atlantic Ocean. DOM was extracted from the water samples using C18 extraction disks and were prepared in 50:50 methanol:water. Ammonium hydroxide was added prior to nanospray in order to solubilize the DOM as well as to increase the ionization efficiency. The samples were continuously infused into the Apollo II ion source with an Advion TriVersa NanoMate system of a Bruker 12 Tesla Apex QE FTICR-MS with resolving powers exceeding 400,000. All samples were analyzed in negative ion mode and were externally and internally calibrated prior to data analysis. Our DOM mass spectra consist of a multitude of peaks spanning the range of 200-850 m/z. Complexity is apparent from the detection of up to 20 peaks per nominal mass at nearly every mass throughout that range. A molecular formula calculator generated molecular formula matches from which van Krevelen plots were constructed for characterization purposes. A wide range of molecules were observed each containing oxygen, sulfur and nitrogen functional groups. We utilize the van Krevelen diagram to assist in clustering the molecules according to their functional group compositions. To test the hypothesis that formation of adducts to DOM serve to protect peptides from bacterial degradation, microcosm experiments were performed with a small isotopically enriched peptide, GGGR. This peptide

  10. Characterization of radiation-induced products of thymidine 3{prime}-monophosphate and thymidylyl (3{prime}{yields}5{prime}) thymidine by high-performance liquid chromatography and laser-desorption fourier-transform mass spectrometry

    SciTech Connect

    Yoshida, H.; Hettich, R.L.

    1994-09-01

    High-performance liquid chromatography (HPLC) and laser-desorption Fourier-transform mass spectrometry (LD FTMS) have been applied for direct measurements of radiation-induced products of nucleic acid constituents containing thymidine. Laser desorption FTMS could be used for the direct detection (neither hydrolyzed nor derivatized) of X-ray-induced decomposition products of aqueous thymidine monophosphate. After these initial experiments, a variety of hydrogenated and hydroxylated thymine standards were acquired and examined by FTMS to assist in the identification of unknown radiation-induced decomposition products of thymine-containing nucleotides and dinucleotides. To extend these studies to dinucleotides, the radiation-induced products generated by the gamma radiolysis of thymidylyl (3{prime}{yields}5{prime}) thymidine (TpT) were isolated by reverse-phase HPLC and identified by LD FTMS. Thymine and thymidine 3{prime}-monophosphate were observed as the major products in this case. Several of the minor products of the HPLC profile were pooled in a single fraction and characterized simultaneously by LD FTMS. The resulting mass spectra indicated the presence of hydroxy-5,6-dihydothymidine monophosphate, 5,6-dihydrothymidine monophosphate and thymidine monophosphate, thymine glycol, hydroxy-5,6-dihydrothymine, 5-hydroxy-methyl-uracil and 5,6-dihydrothymine. The combination of HPLC purification and LD FTMS structural characterization provides a useful tool for the direct measurement of radiation-induced products of nucleotides and dinucleotides. 28 refs., 6 figs., 2 tabs.

  11. Purification and characterization of a naringinase from a newly isolated strain of Bacillus amyloliquefaciens 11568 suitable for the transformation of flavonoids.

    PubMed

    Zhu, Yunping; Jia, Huiyong; Xi, Menglu; Xu, Liya; Wu, Shaoming; Li, Xiuting

    2017-01-01

    An intracellular naringinase from Bacillus amyloliquefaciens 11568 isolated from soil was purified, identified, and characterized. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of the purified enzyme gave a single protein band corresponding to a molecular mass of 32kDa. The optimum pH and temperature for naringinase and its α-l-rhamnosidase and β-d-glucosidase activities were pH 7.5 and 45°C, respectively. The enzymes were stable below 45°C between pH 3.5 and 8.5. The Km and the Vmax of the isolated naringinase were 0.95mmol/L and 3847.3mmol/(L·min), respectively. The isolated naringinase was capable of hydrolyzing naringin, neohesperidin, and other glycosides. Additionally, a concentration of 4U/mL of the enzyme in citrus juice was sufficient to remove the naringin and alleviate the bitterness of the juice. These results provide an in-depth insight into the structure of the naringinase and the hydrolysis of naringin and other flavonoids. PMID:27507445

  12. Herbicide Transformation

    PubMed Central

    Lanzilotta, R. P.; Pramer, David

    1970-01-01

    Replacement cultures liberated 3,4-dichloroaniline (DCA) from 3,4-dichloropropionanilide (propanil). The kinetics of the conversion suggest a requirement for de novo enzyme synthesis, but the system was not influenced by chloramphenicol or puromycin. Enzyme activity was detected when acetanilide (Km = 0.195 mm) was used to replace propanil as substrate. Fungal acylamidase (E.C. 3.5.1., an aryl acylamine amidohydrolase) was concentrated by salt precipitation and characterized. The Fusarium solani acylamidase exhibited an optimum at pH 7.5 to 9.0 and was inactivated in 10 min at 50 C. The enzyme was not sensitive to methyl-carbamate or organophosphate insecticides, but the herbicide, Ramrod (N-isopropyl-2-chloroacetanilide), acted as a competitive inhibitor of acetanilide hydrolysis (Ki = 0.167 mm). Hydrolysis rates were decreased by various para substitutions of acetanilide. Chloro substitution in the acyl moiety of acetanilide also reduced the rate of hydrolysis. 3,4-Dichloroacetanilide was less susceptible to enzyme action than acetanilide, but 3,4-dichloropropionanilide was hydrolyzed much more rapidly than propionanilide. The fungal acylamidase was highly specific for N-acetylarylamines. It did not catalyze hydrolysis of formanilide, butyranilide, dicryl, Karsil, fenuron, monuron, or isopropyl-N-phenylcarbamate. It appears to differ from acylamidases that have been isolated from rice, rat liver, chick kidney, and Neurospora. PMID:5437306

  13. Natural and anthropogenic impacts on biogeochemical cycle in Yangtze River basin: Source, transformation and fate of dissolved organic matter (DOM) characterized by 3-D fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Gan, Shuchai; Wu, Ying; Bao, Hongyan; Zhang, Jing

    2013-04-01

    Inland waters play an important role in the global carbon cycle as reactors for DOM cycling, transformation and transportation. With large amounts of terrestrial DOM, the Yangtze River is vital for coastal environment and ecosystem. In the context of climate change, it's critical to evaluate both hydrodynamic conditions and increasing human activities' impacts on biogeochemical cycle of DOM in Yangtze River across different climatic and hydrologic regions which are poorly understood. What's more, the hydrologic condition changes caused by the Three Gorges Dam (TGD, world's largest power station in terms of installed capacity) have recently proven to be a partition factor for fluvial particle. However, it's still an enigma for dissolved matter cycle. To address those issues, this study applies EEMs combined with bulk characteristics, chlorophyll and absorption spectrum in an attempt to assess characteristics and dynamics of DOM in Yangtze River. It's a novel optical approach that could 'see' molecular structure of DOM without the limits of time-consuming and laborious molecular measurements. Combined with parallel factor analysis, 5 individual fluorescent components have been identified: 3 humic-like (H1, H2, H3) and 2 protein-like components (P1, P2). With typical bioavailability and photo-reactivity, these components suggest different sources and dynamics. On the whole, both DOC and the sum of all 5 components (? Fluo) increased remarkably from the upper reach especially to the Three Gorge Dam and thereafter remained constant (R2between DOC and - Fluo: 0.92). The protein-like components (- P) accounted for 1/4 of - Fluo with apparently weak correlations with DOC and chlorophyll, which implied that the DOM is not dominated by autochthonous production, especially for the upper reach with high concentration of total suspended matter. As for Humic-like component, increasing H1 and DOC in the TGD reservoir area implied impacts from human activities there with intercept

  14. Enterprise transformation :lessons learned, pathways to success.

    SciTech Connect

    Slavin, Adam M.; Woodard, Joan Brune

    2006-05-01

    In this report, we characterize the key themes of transformation and tie them together in a ''how to'' guide. The perspectives were synthesized from strategic management literature, case studies, and from interviews with key management personnel from private industry on their transformation experiences.

  15. Fourier transform infrared (FT-IR) spectroscopy and imaging of the nucleus to characterize DNA contributions in different phases of the cell cycle

    NASA Astrophysics Data System (ADS)

    Tiwari, Saumya; Zong, Xinying; Holton, Sarah E.; Prasanth, K. V.; Bhargava, Rohit

    2015-03-01

    Determination of neoplasia is largely dependent on the state of cell growth. Infrared (IR) spectroscopy has the potential to measure differences between normal and cancerous cells. When analyzing biopsy sections using IR spectroscopy, careful analyses become important since biochemical variations may be misinterpreted due to variations in cell cycle. Processes like DNA replication, transcription and translation to produce proteins are important in determining if the cells are actively dividing but no studies on this aspect using IR spectroscopy have been conducted on isolated cell nuclei. Nuclei hold critical information about the phase of cell and its capacity to divide, but IR spectra of nuclei are often confounded by cytoplasmic signals during data acquisition from intact cells and tissues. Therefore, we sought to separate nuclear signals from cytoplasmic signals and identify spectral differences that characterize different phases of the cell cycle. Both cells and isolated nuclei were analyzed to assess the effect of the cytoplasmic background and to identify spectral changes in nuclei in different phases of cell cycle. We observed that signals of DNA could be obtained when imaging nuclei isolated from cells in different phases of cell cycle, which is in contrast to the oft-cited case in cells wherein nuclear contributions are obscured. The differences across cell cycle phases were more pronounced in nucleic acid regions of the spectra, showing that the use of nuclear spectrum can provide additional information on cellular state. These results can aid in developing computational models that extract nuclear spectra from whole cells and tissues for more accurate assessment of biochemical variations.

  16. Characterization of CZTSSe photovoltaic device with an atomic layer-deposited passivation layer

    SciTech Connect

    Wu, Wei Cao, Yanyan; Caspar, Jonathan V.; Guo, Qijie; Johnson, Lynda K.; Mclean, Robert S.; Malajovich, Irina; Choudhury, Kaushik Roy

    2014-07-28

    We describe a CZTSSe (Cu{sub 2}ZnSn(S{sub 1−x},Se{sub x}){sub 4}) photovoltaic (PV) device with an ALD (atomic layer deposition) coated buffer dielectric layer for CZTSSe surface passivation. An ALD buffer layer, such as TiO{sub 2}, can be applied in order to reduce the interface recombination and improve the device's open-circuit voltage. Detailed characterization data including current-voltage, admittance spectroscopy, and capacitance profiling are presented in order to compare the performance of PV devices with and without the ALD layer.

  17. Effects of iodinated contrast on various magnetic resonance imaging sequences and field strength: Implications for characterization of hemorrhagic transformation in acute stroke therapy

    PubMed Central

    Morales, Humberto; Lemen, Lisa; Samaratunga, Ranasinghage; Nguyen, Peter; Tomsick, Thomas

    2016-01-01

    AIM: To characterize the effects of iodinated contrast material (ICM) on magnetic resonance imaging (MRI) comparing different sequences and magnetic fields, with emphasis to similarities/differences with well-known signal characteristics of hemorrhage in the brain. METHODS: Aliquots of iopamidol and iodixanol mixed with normal saline were scanned at 1.5T and 3T. Signal intensity (SI) was measured using similar spin-echo (SE)-T1, SE-T2, gradient-echo (GRE) and fluid-attenuation-inversion-recovery (FLAIR) sequences at both magnets. Contrast to noise ratio (CNR) (SI contrast-SI saline/SD noise) for each aliquot were calculated and Kruskall-wallis test and graphic analysis was used to compare different pulse sequences and ICMs. RESULTS: Both ICM showed increased SI on SE-T1 and decreased SI on SE-T2, GRE and FLAIR at both 1.5T and 3T, as the concentration was increased. By CNR measurements, SE-T2 had the greatest conspicuity at 3T with undiluted iopamidol (92.6 ± 0.3, P < 0.00) followed by iodixanol (77.5 ± 0.9, P < 0.00) as compared with other sequences (CNR range: 15-40). While SE-T2 had greatest conspicuity at 1.5T with iopamidol (49.3 ± 1, P < 0.01), SE-T1 showed similar or slightly better conspicuity (20.8 ± 4) than SE-T2 with iodixanol (23 ± 1.7). In all cases, hypo-intensity on GRE was less conspicuous than on SE-T2. CONCLUSION: Iodixanol and iopamidol shorten T1 and T2 relaxation times at both 1.5T and 3T. Hypo-intensity due to shortened T2 relaxation time is significantly more conspicuous than signal changes on T1-WI, FLAIR or GRE. Variations in signal conspicuity according to pulse sequence and to type of ICM are exaggerated at 3T. We postulate T2 hypointensity with less GRE conspicuity differentiates ICM from hemorrhage; given the well-known GRE hypointensity of hemorrhage. Described signal changes may be relevant in the setting of recent intra-arterial or intravenous ICM administration in translational research and/or human stroke therapy. PMID

  18. Co-Ordinate Transformations for Second Order Systems. Part II: Elementary Structure-Preserving Transformations

    NASA Astrophysics Data System (ADS)

    Garvey, S. D.; Friswell, M. I.; Prells, U.

    2002-12-01

    It has been shown in a previous paper that there is a real-valued transformation from the general N -degree-of-freedom second order system to a second order system characterized by diagonal matrices. An immediate extension of this fact is that for any second order system, there is a set of real-valued transformations (the structure-preserving transformations) which transform this system to a different second order system having identical characteristic behaviour. There are several possible reasons why it may be very useful to achieve a particular structure in the transformed system. It is obvious that a diagonal structure is extremely useful and a method has been devised for determining the diagonalizing transformation from the solution of the usual (complex) eigenvalue-eigenvector problem. This paper begins by outlining the usefulness of some other structures. Then it defines a class of elementary structure-preserving co-ordinate transformations that transform from one N -degree-of-freedom second order system to another. The term elementary is applied because any one of these transformations is the minimum-rank modification of the identity transformation. The changes occurring in the system matrices as a result of the application of one such elementary transformation transpire to be very simple in form, they are low rank, and they can be computed very efficiently. This paper provides the fundamental tools to enable the design of structure-preserving co-ordinate transformations which transform a second order system originally characterized by three general matrices in stages into a mathematically similar second order system characterized by three diagonal matrices. The procedure by which the individual elementary transformations are obtained is still under development and it is not discussed in this paper. However, an illustration is given of a five-degree-of-freedom self-adjoint system being transformed into tridiagonal form.

  19. Phase Transformations in Confined Nanosystems

    SciTech Connect

    Shield, Jeffrey E.; Belashchenko, Kirill

    2014-04-29

    This project discovered that non-equilibrium structures, including chemically ordered structures not observed in bulk systems, form in isolated nanoscale systems. Further, a generalized model was developed that effectively explained the suppression of equilibrium phase transformations. This thermodynamic model considered the free energy decrease associated with the phase transformation was less than the increase in energy associated with the formation of an interphase interface, therefore inhibiting the phase transformation. A critical diameter exists where the system transitions to bulk behavior, and a generalized equation was formulated that successfully predicted this transition in the Fe-Au system. This provided and explains a new route to novel structures not possible in bulk systems. The structural characterization was accomplished using transmission electron microscopy in collaboration with Matthew Kramer of Ames Laboratory. The PI and graduate student visited Ames Laboratory several times a year to conduct the experiments.

  20. Admittance and subthreshold characteristics of atomic-layer-deposition Al2O3 on In0.53Ga0.47As in surface and buried channel flatband metal-oxide-semiconductor field effect transistors

    NASA Astrophysics Data System (ADS)

    Paterson, G. W.; Bentley, S. J.; Holland, M. C.; Thayne, I. G.; Ahn, J.; Long, R. D.; McIntyre, P. C.; Long, A. R.

    2012-05-01

    The admittances and subthreshold characteristics of capacitors and MOSFETs on buried and surface In0.53Ga0.47As channel flatband wafers, with a dielectric of Al2O3 deposited on In0.53Ga0.47As, are reported. The admittance characteristics of both wafers indicate the presence of defect states within the oxide, in common with a number of other oxides on In0.53Ga0.47As. The two wafers studied have not been hydrogen annealed, but do show some similar features to FGA treated oxides on n+ substrates. We discuss how the possible presence of residual hydroxyl ions in as-grown Al2O3 may explain these similarities and also account for many of the changes in the properties of FGA treated n+ samples. The issues around the comparison of subthreshold swing (SS) results and the impact of transistor design parameters on the energy portion of the defect state distribution affecting efficient device switching are discussed. The interface state model is applied to low source-drain voltage SS data to extract an effective interface state density (Dit) that includes interface and oxide traps. The logarithmic gate voltage sweep rate dependence of the SS Dit is used to extract an oxide trap density (Dot) and a simple method is used to estimate the Fermi level position within the band gap, Et. The Al2O3 Dit(Et) and Dot(Et) distributions are found to be similar to each other and to the results of our analysis of Gd0.25Ga0.15O0.6/Ga2O3 and HfO2/Al2O3 on In0.53Ga0.47As, adding weight to the suggestion of there being a common defect state distribution and perhaps a common cause of defects states for a number of oxides on In0.53Ga0.47As.

  1. Transforming the Way We Teach Function Transformations

    ERIC Educational Resources Information Center

    Faulkenberry, Eileen Durand; Faulkenberry, Thomas J.

    2010-01-01

    In this article, the authors discuss "function," a well-defined rule that relates inputs to outputs. They have found that by using the input-output definition of "function," they can examine transformations of functions simply by looking at changes to input or output and the respective changes to the graph. Applying transformations to the input…

  2. Symplectic wavelet transformation.

    PubMed

    Fan, Hong-Yi; Lu, Hai-Liang

    2006-12-01

    Usually a wavelet transform is based on dilated-translated wavelets. We propose a symplectic-transformed-translated wavelet family psi(*)(r,s)(z-kappa) (r,s are the symplectic transform parameters, |s|(2)-|r|(2)=1, kappa is a translation parameter) generated from the mother wavelet psi and the corresponding wavelet transformation W(psi)f(r,s;kappa)=integral(infinity)(-infinity)(d(2)z/pi)f(z)psi(*)(r,s)(z-kappa). This new transform possesses well-behaved properties and is related to the optical Fresnel transform in quantum mechanical version. PMID:17099740

  3. Hydrolytic Amino Acids Employed as a Novel Organic Nitrogen Source for the Preparation of PGPF-Containing Bio-Organic Fertilizer for Plant Growth Promotion and Characterization of Substance Transformation during BOF Production.

    PubMed

    Zhang, Fengge; Meng, Xiaohui; Feng, Chenglong; Ran, Wei; Yu, Guanghui; Zhang, Yingjun; Shen, Qirong

    2016-01-01

    Opportunity costs seriously limit the large-scale production of bio-organic fertilizers (BOFs) both in China and internationally. This study addresses the utilization of amino acids resulting from the acidic hydrolysis of pig corpses as organic nitrogen sources to increase the density of TrichodermaharzianumT-E5 (a typical plant growth-promoting fungi, PGPF). This results in a novel, economical, highly efficient and environmentally friendly BOF product. Fluorescence excitation-emission matrix (EEM) spectroscopy combined with fluorescence regional integration (FRI) was employed to monitor compost maturity levels, while pot experiments were utilized to test the effects of this novel BOF on plant growth. An optimization experiment, based on response surface methodologies (RSMs), showed that a maximum T-E5 population (3.72 × 108 ITS copies g-1) was obtained from a mixture of 65.17% cattle manure compost (W/W), 19.33% maggot manure (W/W), 15.50% (V/W)hydrolytic amino acid solution and 4.69% (V/W) inoculum at 28.7°C after a 14 day secondary solid fermentation. Spectroscopy analysis revealed that the compost transformation process involved the degradation of protein-like substances and the formation of fulvic-like and humic-like substances. FRI parameters (PI, n, PII, n, PIII, n and PV, n) were used to characterize the degree of compost maturity. The BOF resulted in significantly higher increased chlorophyll content, shoot length, and shoot and root dry weights of three vegetables (cucumber, tomato and pepper) by 9.9%~22.4%, 22.9%~58.5%, 31.0%~84.9%, and 24.2%~34.1%, respectively. In summary, this study presents an operational means of increasing PGPF T-E5 populations in BOF to promote plant growth with a concomitant reduction in production cost. In addition, a BOF compost maturity assessment using fluorescence EEM spectroscopy and FRI ensured its safe field application. PMID:26974549

  4. Arsenic(V) Reduction in Relation to Iron(III) Transformation and Molecular Characterization of the Structural and Functional Microbial Community in Sediments of a Basin-Fill Aquifer in Northern Utah

    PubMed Central

    Mirza, Babur S.; Muruganandam, Subathra; Meng, Xianyu; Sorensen, Darwin L.; Dupont, R. Ryan

    2014-01-01

    Basin-fill aquifers of the Southwestern United States are associated with elevated concentrations of arsenic (As) in groundwater. Many private domestic wells in the Cache Valley Basin, UT, have As concentrations in excess of the U.S. EPA drinking water limit. Thirteen sediment cores were collected from the center of the valley at the depth of the shallow groundwater and were sectioned into layers based on redoxmorphic features. Three of the layers, two from redox transition zones and one from a depletion zone, were used to establish microcosms. Microcosms were treated with groundwater (GW) or groundwater plus glucose (GW+G) to investigate the extent of As reduction in relation to iron (Fe) transformation and characterize the microbial community structure and function by sequencing 16S rRNA and arsenate dissimilatory reductase (arrA) genes. Under the carbon-limited conditions of the GW treatment, As reduction was independent of Fe reduction, despite the abundance of sequences related to Geobacter and Shewanella, genera that include a variety of dissimilatory iron-reducing bacteria. The addition of glucose, an electron donor and carbon source, caused substantial shifts toward domination of the bacterial community by Clostridium-related organisms, and As reduction was correlated with Fe reduction for the sediments from the redox transition zone. The arrA gene sequencing from microcosms at day 54 of incubation showed the presence of 14 unique phylotypes, none of which were related to any previously described arrA gene sequence, suggesting a unique community of dissimilatory arsenate-respiring bacteria in the Cache Valley Basin. PMID:24632255

  5. Evaluate and characterize mechanisms controlling transport, fate and effects of Army smokes in the aerosol wind tunnel: Transport, transformations, fate, and terrestrial ecological effects of red phosphorus-butyl rubber and white phosphorus obscurant smokes: Final report

    SciTech Connect

    Van Voris, P.; Ligotke, M.W.; McFadden, K.M.; Li, S.M.W.; Thomas, B.L.; Cataldo, D.A.; Garland, T.R.; Fredrickson, J.K.; Bean, R.M.; Carlile, D.W.

    1987-10-01

    An evaluation of the terrestrial transport, transformations and ecological effects of phosphorus (red phosphorus-butyl rubber (RP/BR)) smoke obscurant was performed at Pacific Northwest Laboratory. A similar evaluation using white phosphorus (WP) smoke/obscurant is currently proceeding. The objective is to characterize the effects of smokes and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of representative of soils of those sites; and (3) soil microbiological communities. The influence and interactions of smoke/obscurant concentration, relative humidity (25%, 60%, 90% and simulated rain) and wind speed of 0.22 to 4.45 m/s by smoke is assessed. Five plant species and four soils were exposed to both single and repeated doses of RP/BR smokes in the Pacific Northwest Laboratory ''P-3'' rated recirculating environmental wind tunnel. Detailed results for RP/BR and limited results for WP are presented. Toxicity symptoms for plants exposed for 2, 4, 6, and 8 hours to concentrations of RP/BR ranging from 200 mg/m/sup 3/ included leaf tip burn, leaf curl, leaf abscission and drop, floral abortion, chlorosis, neucrotic spotting, wilting, desiccation and dieback. Grass and bushbean were the most sensitive. The intensity and duration of these effects varied. Soils effects data suggest that there is an increase in the mobility of selected trace elements after exposure; however, this effect appears to be ameliorated with time. Soil microbial community effects show a reduction in the production of nitrate after soil is exposed to RP/BR smoke. Most of the plant, soil and soil microbial effects are transient in nature and are somewhat less intense resulting from repeated exposures; however, there is evidence that some of these environmental impacts may be persistent. 43 refs., 44 figs., 67 tabs.

  6. Hydrolytic Amino Acids Employed as a Novel Organic Nitrogen Source for the Preparation of PGPF-Containing Bio-Organic Fertilizer for Plant Growth Promotion and Characterization of Substance Transformation during BOF Production

    PubMed Central

    Feng, Chenglong; Ran, Wei; Yu, Guanghui; Zhang, Yingjun; Shen, Qirong

    2016-01-01

    Opportunity costs seriously limit the large-scale production of bio-organic fertilizers (BOFs) both in China and internationally. This study addresses the utilization of amino acids resulting from the acidic hydrolysis of pig corpses as organic nitrogen sources to increase the density of TrichodermaharzianumT-E5 (a typical plant growth-promoting fungi, PGPF). This results in a novel, economical, highly efficient and environmentally friendly BOF product. Fluorescence excitation-emission matrix (EEM) spectroscopy combined with fluorescence regional integration (FRI) was employed to monitor compost maturity levels, while pot experiments were utilized to test the effects of this novel BOF on plant growth. An optimization experiment, based on response surface methodologies (RSMs), showed that a maximum T-E5 population (3.72 × 108 ITS copies g−1) was obtained from a mixture of 65.17% cattle manure compost (W/W), 19.33% maggot manure (W/W), 15.50% (V/W)hydrolytic amino acid solution and 4.69% (V/W) inoculum at 28.7°C after a 14 day secondary solid fermentation. Spectroscopy analysis revealed that the compost transformation process involved the degradation of protein-like substances and the formation of fulvic-like and humic-like substances. FRI parameters (PI, n, PII, n, PIII, n and PV, n) were used to characterize the degree of compost maturity. The BOF resulted in significantly higher increased chlorophyll content, shoot length, and shoot and root dry weights of three vegetables (cucumber, tomato and pepper) by 9.9%~22.4%, 22.9%~58.5%, 31.0%~84.9%, and 24.2%~34.1%, respectively. In summary, this study presents an operational means of increasing PGPF T-E5 populations in BOF to promote plant growth with a concomitant reduction in production cost. In addition, a BOF compost maturity assessment using fluorescence EEM spectroscopy and FRI ensured its safe field application. PMID:26974549

  7. A dynamic phase-field model for structural transformations and twinning: Regularized interfaces with transparent prescription of complex kinetics and nucleation. Part I: Formulation and one-dimensional characterization

    NASA Astrophysics Data System (ADS)

    Agrawal, Vaibhav; Dayal, Kaushik

    2015-12-01

    The motion of microstructural interfaces is important in modeling twinning and structural phase transformations. Continuum models fall into two classes: sharp-interface models, where interfaces are singular surfaces; and regularized-interface models, such as phase-field models, where interfaces are smeared out. The former are challenging for numerical solutions because the interfaces need to be explicitly tracked, but have the advantage that the kinetics of existing interfaces and the nucleation of new interfaces can be transparently and precisely prescribed. In contrast, phase-field models do not require explicit tracking of interfaces, thereby enabling relatively simple numerical calculations, but the specification of kinetics and nucleation is both restrictive and extremely opaque. This prevents straightforward calibration of phase-field models to experiment and/or molecular simulations, and breaks the multiscale hierarchy of passing information from atomic to continuum. Consequently, phase-field models cannot be confidently used in dynamic settings. This shortcoming of existing phase-field models motivates our work. We present the formulation of a phase-field model - i.e., a model with regularized interfaces that do not require explicit numerical tracking - that allows for easy and transparent prescription of complex interface kinetics and nucleation. The key ingredients are a re-parametrization of the energy density to clearly separate nucleation from kinetics; and an evolution law that comes from a conservation statement for interfaces. This enables clear prescription of nucleation - through the source term of the conservation law - and kinetics - through a distinct interfacial velocity field. A formal limit of the kinetic driving force recovers the classical continuum sharp-interface driving force, providing confidence in both the re-parametrized energy and the evolution statement. We present some 1D calculations characterizing the formulation; in a

  8. 28-Channel rotary transformer

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1981-01-01

    Transformer transmits power and digital data across rotating interface. Array has many parallel data channels, each with potential l megabaud data rate. Ferrite-cored transformers are spaced along rotor; airgap between them reduces crosstalk.

  9. Equations For Rotary Transformers

    NASA Technical Reports Server (NTRS)

    Salomon, Phil M.; Wiktor, Peter J.; Marchetto, Carl A.

    1988-01-01

    Equations derived for input impedance, input power, and ratio of secondary current to primary current of rotary transformer. Used for quick analysis of transformer designs. Circuit model commonly used in textbooks on theory of ac circuits.

  10. Chemical Transformation Simulator

    EPA Science Inventory

    The Chemical Transformation Simulator (CTS) is a web-based, high-throughput screening tool that automates the calculation and collection of physicochemical properties for an organic chemical of interest and its predicted products resulting from transformations in environmental sy...

  11. Transformation of Pasteurella novicida

    PubMed Central

    Tyeryar, Franklin J.; Lawton, William D.

    1969-01-01

    Deoxyribonucleic acid from a streptomycin-resistant mutant of Pasteurella novicida transformed portions of P. novicida streptomycin-sensitive populations to streptomycin-resistant. Similarly, mutants auxotrophic for tryptophan or purine biosynthesis were also transformed to nutritional independence. PMID:5359612

  12. Shiftable multiscale transforms

    NASA Technical Reports Server (NTRS)

    Simoncelli, Eero P.; Freeman, William T.; Adelson, Edward H.; Heeger, David J.

    1992-01-01

    A type of translational invariance, referred to as shiftability, is defined for wavelet transforms. The property of shiftability is first discussed with respect to individual parameters: spatial position, orientation, and scale. The discussion then focuses on transformations that are simultaneously shiftable with respect to subsets of these parameters. It is shown that the critical sampling condition on the wavelet transforms must be relaxed to achieve shiftability. Two example transforms are implemented and applied to several signal and image processing problems.

  13. Achieving Perspective Transformation.

    ERIC Educational Resources Information Center

    Nowak, Jens

    Perspective transformation is a consciously achieved state in which the individual's perspective on life is transformed. The new perspective serves as a vantage point for life's actions and interactions, affecting the way life is lived. Three conditions are basic to achieving perspective transformation: (1) "feeling" experience, i.e., getting in…

  14. Transformation of Dermatofibrosarcoma Protuberans into a Fibrosarcoma

    PubMed Central

    Sbai, Mohamed Ali; Benzarti, Sofien; Bouzaidi, Khaled; Sbei, Feten; Maalla, Riadh

    2016-01-01

    Dermatofibrosarcoma protuberans is a rare cutaneous mesenchymal tumor characterized by a low potential of malignancy with a very low rate of metastasis but an important rate of local recurrence. Its transformation into a fibrosarcoma is exceptional, responsible for a higher metastatic potential. This transformation implies a closer surveillance. Through a case report and literature review, we will try to expose epidemiological, clinical, histological, therapeutic, and outcome particularities of this entity. PMID:26955135

  15. Signals on graphs: Transforms and tomograms

    NASA Astrophysics Data System (ADS)

    Vilela Mendes, R.; Mendes, Hugo C.; Araújo, Tanya

    2016-05-01

    Development of efficient tools for the representation of large datasets is a precondition for the study of dynamics on networks. Generalizations of the Fourier transform on graphs have been constructed through projections on the eigenvectors of graph matrices. By exploring mappings of the spectrum of these matrices we show how to construct more general transforms, in particular wavelet-like transforms on graphs. For time-series, tomograms, a generalization of the Radon transforms to arbitrary pairs of non-commuting operators, are positive bilinear transforms with a rigorous probabilistic interpretation which provide a full characterization of the signals and are robust in the presence of noise. Here the notion of tomogram is also extended to signals on arbitrary graphs.

  16. Transformation of the diamond /110/ surface

    NASA Technical Reports Server (NTRS)

    Pepper, S. V.

    1982-01-01

    The diamond surface undergoes a transformation in its electronic structure by a vacuum anneal at approximately 900 C. This transformation is characterized by the appearance of a feature in the band gap region of the energy loss spectrum. The kinetics of the transformation on the (110) surface is studied by observing the growth of this feature with time and temperature. The transformation is found to be consistent with first-order kinetics with an activation energy of 4.8 eV. It is also found that the band gap feature could be removed by exposure of the transformed surface to excited hydrogen. The results are consistent with the polished diamond (110) surface being covered with hydrogen which removes the band gap states and can be thermally desorbed at approximately 900 C.

  17. Note: Tesla transformer damping

    NASA Astrophysics Data System (ADS)

    Reed, J. L.

    2012-07-01

    Unexpected heavy damping in the two winding Tesla pulse transformer is shown to be due to small primary inductances. A small primary inductance is a necessary condition of operability, but is also a refractory inefficiency. A 30% performance loss is demonstrated using a typical "spiral strip" transformer. The loss is investigated by examining damping terms added to the transformer's governing equations. A significant alteration of the transformer's architecture is suggested to mitigate these losses. Experimental and simulated data comparing the 2 and 3 winding transformers are cited to support the suggestion.

  18. ASC Coordinate Transformation---The Pixlib Library

    NASA Astrophysics Data System (ADS)

    He, H.; McDowell, J.; Conroy, M.

    We describe a coordinate library for AXAF data analysis. The library handles transformations between celestial coordinates and instrumental (mirror, focal plane, detector pixel) coordinate systems. The need for careful transformations is driven by the accuracy of the detectors and the attitude determination system. The coordinate systems are characterized by parameter files generated from experimental and calibration data. Transformation calculations are performed by matrix-representation routines for maximum flexibility. This library is implemented in ANSI C, and uses the SAO IRAF-compatible parameter interface.

  19. Modelling the pulse transformer in SPICE

    NASA Astrophysics Data System (ADS)

    Godlewska, Malgorzata; Górecki, Krzysztof; Górski, Krzysztof

    2016-01-01

    The paper is devoted to modelling pulse transformers in SPICE. It shows the character of the selected models of this element, points out their advantages and disadvantages, and presents the results of experimental verification of the considered models. These models are characterized by varying degrees of complexity - from linearly coupled linear coils to nonlinear electrothermal models. The study was conducted for transformer with ring cores made of a variety of ferromagnetic materials, while exciting the sinusoidal signal of a frequency 100 kHz and different values of load resistance. The transformers operating conditions under which the considered models ensure the acceptable accuracy of calculations are indicated.

  20. Transformation pathways of liposomes.

    PubMed

    Hotani, H

    1984-09-01

    Liposomes undergoing transformation were observed by dark-field light microscopy in order to study the role of lipid in morphogenesis of biological vesicular structures. Liposomes were found to transform sequentially in a well-defined manner through one of several transformation pathways. A circular biconcave form was an initial shape in all the pathways and it transformed into a stable thin flexible filament or small spheres via a variety of regularly shaped vesicles which possessed geometrical symmetry. The transformation was reversible up to a certain point in each pathway. Osmotic pressure was found to be the driving force for the transformations. Biological membrane vesicles such as trypsinized red cell ghosts also transformed by similar pathways. PMID:6548263

  1. Cells transformed by murine herpesvirus 68 (MHV-68) release compounds with transforming and transformed phenotype suppressing activity resembling growth factors.

    PubMed

    Šupolíková, M; Staňová, A Vojs; Kúdelová, M; Marák, J; Zelník, V; Golais, F

    2015-12-01

    In this study, we investigated the medium of three cell lines transformed with murine herpesvirus 68 (MHV-68) in vitro and in vivo, 68/HDF, 68/NIH3T3, and S11E, for the presence of compounds resembling growth factors of some herpesviruses which have displayed transforming and transformed phenotype suppressing activity in normal and tumor cells. When any of spent medium was added to cell culture we observed the onset of transformed phenotype in baby hamster kidney cells (BHK-21) cells and transformed phenotype suppressing activity in tumor human epithelial cells (HeLa). In media tested, we have identified the presence of putative growth factor related to MHV-68 (MHGF-68). Its bivalent properties have been blocked entirely by antisera against MHV-68 and two monoclonal antibodies against glycoprotein B (gB) of MHV-68 suggesting viral origin of MHGF-68. The results of initial efforts to separate MHGF-68 on FPLC Sephadex G15 column in the absence of salts revealed the loss of its transforming activity but transformed phenotype suppressing activity retained. On the other hand, the use of methanol-water mobile phase on RP-HPLC C18 column allowed separation of MHGF-68 to two compounds. Both separated fractions, had only the transforming activity to normal cells. Further experiments exploring the nature and the structure of hitherto unknown MHGF-68 are now in the progress to characterize its molecular and biological properties. PMID:26666191

  2. Analyses of temperature-dependent interface states, series resistances, and AC electrical conductivities of Al/p—Si and Al/Bi4Ti3O12/p—Si structures by using the admittance spectroscopy method

    NASA Astrophysics Data System (ADS)

    Mert, Yıldırım; Perihan, Durmuş; Şemsettin, Altındal

    2013-10-01

    In this study, Al/p—Si and Al/Bi4Ti3O12/p—Si structures are fabricated and their interface states (Nss), the values of series resistance (Rs), and AC electrical conductivity (σac) are obtained each as a function of temperature using admittance spectroscopy method which includes capacitance—voltage (C—V) and conductance—voltage (G—V) measurements. In addition, the effect of interfacial Bi4Ti3O12 (BTO) layer on the performance of the structure is investigated. The voltage-dependent profiles of Nss and Rs are obtained from the high-low frequency capacitance method and the Nicollian method, respectively. Experimental results show that Nss and Rs, as strong functions of temperature and applied bias voltage, each exhibit a peak, whose position shifts towards the reverse bias region, in the depletion region. Such a peak behavior is attributed to the particular distribution of Nss and the reordering and restructuring of Nss under the effect of temperature. The values of activation energy (Ea), obtained from the slope of the Arrhenius plot, of both structures are obtained to be bias voltage-independent, and the Ea of the metal-ferroelectric-semiconductor (MFS) structure is found to be half that of the metal—semiconductor (MS) structure. Furthermore, other main electrical parameters, such as carrier concentration of acceptor atoms (NA), built-in potential (Vbi), Fermi energy (EF), image force barrier lowering (Δ Φb), and barrier height (Φb), are extracted using reverse bias C-2—V characteristics as a function of temperature.

  3. Influence of composition of the near-surface graded-gap layer on the admittance of metal-insulator-semiconductor structures based on graded-gap MBE n-Hg1-xCdxTe in wide temperature range

    NASA Astrophysics Data System (ADS)

    Voitsekhovskii, A. V.; Nesmelov, S. N.; Dzyadukh, S. M.

    2014-12-01

    Influence of the CdTe content in a near-surface graded-gap layer on the admittance of MIS-structures fabricated on the basis of heteroepitaxial Hg1-xCdxTe (x = 0.22-0.23 and 0.31-0.32) films grown by molecular beam epitaxy was investigated in a wide temperature range. It is shown that a temperature drop from 77 K to 8 K results in a decrease of hysteresis of the capacitance-voltage (C-V) characteristics and a decrease of frequencies which corresponds to a high-frequency behaviour of C-V characteristics of MIS-structures based on n-HgCdTe (x = 0.22-0.23) with and without graded-gap layersand also for MIS-structures based on n-HgCdTe (x = 0.31-0.32). Temperature dependences of the resistance of the epitaxial film bulk and differential resistance of the space-charge region (SCR) in strong inversion mode were studied. The experimental results can be explained by the fact that for MIS-structures based on n-HgCdTe (x = 0.22-0.23) with the graded-gap layers and for MIS-structures based on n-HgCdTe (x = 0.31-0.32), the differential resistance of SCR is limited by Shockley-Read generation at 25-77 K. Differential resistance of SCR for MIS-structures based on n-HgCdTe (x = 0.22-0.23) without the graded-gap layers is limited by tunnelling through deep levels at 8-77 K.

  4. Fourier-transform optical microsystems

    NASA Technical Reports Server (NTRS)

    Collins, S. D.; Smith, R. L.; Gonzalez, C.; Stewart, K. P.; Hagopian, J. G.; Sirota, J. M.

    1999-01-01

    The design, fabrication, and initial characterization of a miniature single-pass Fourier-transform spectrometer (FTS) that has an optical bench that measures 1 cm x 5 cm x 10 cm is presented. The FTS is predicated on the classic Michelson interferometer design with a moving mirror. Precision translation of the mirror is accomplished by microfabrication of dovetailed bearing surfaces along single-crystal planes in silicon. Although it is miniaturized, the FTS maintains a relatively high spectral resolution, 0.1 cm-1, with adequate optical throughput.

  5. Magnetically Controlled Variable Transformer

    NASA Technical Reports Server (NTRS)

    Kleiner, Charles T.

    1994-01-01

    Improved variable-transformer circuit, output voltage and current of which controlled by use of relatively small current supplied at relatively low power to control windings on its magnetic cores. Transformer circuits of this type called "magnetic amplifiers" because ratio between controlled output power and power driving control current of such circuit large. This ratio - power gain - can be as large as 100 in present circuit. Variable-transformer circuit offers advantages of efficiency, safety, and controllability over some prior variable-transformer circuits.

  6. Phase Transformation in Cast Superaustenitic Stainless Steels

    SciTech Connect

    Nathaniel Steven Lee Phillips

    2006-12-12

    Superaustenitic stainless steels constitute a group of Fe-based alloys that are compositionally balanced to have a purely austenitic matrix and exhibit favorable pitting and crevice corrosion resistant properties and mechanical strength. However, intermetallic precipitates such as sigma and Laves can form during casting or exposure to high-temperature processing, which degrade the corrosion and mechanical properties of the material. The goal of this study was to accurately characterize the solid-solid phase transformations seen in cast superaustenitic stainless steels. Heat treatments were performed to understand the time and temperature ranges for intermetallic phase formations in alloys CN3MN and CK3MCuN. Microstructures were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy and wavelength dispersive spectroscopy (EDS, WDS). The equilibrium microstructures, composed primarily of sigma and Laves within purely austenitic matrices, showed slow transformation kinetics. Factors that determine the extent of transformation, including diffusion, nucleation, and growth, are discussed.

  7. Partially transformed relaxor ferroelectric single crystals with distributed phase transformation behavior

    NASA Astrophysics Data System (ADS)

    Gallagher, John A.

    2015-11-01

    Relaxor ferroelectric single crystals such as PMN-PT and PIN-PMN-PT undergo field driven phase transformations when electrically or mechanically loaded in crystallographic directions that provide a positive driving force for the transformation. The observed behavior in certain compositions is a phase transformation distributed over a range of fields without a distinct forward or reverse coercive field. This work focuses on the material behavior that is observed when the crystals are loaded sufficiently to drive a partial transformation and then unloaded, as might occur when driving a transducer to achieve high power levels. Distributed transformations have been modeled using a normal distribution of transformation thresholds. A set of experiments was conducted to characterize the hysteresis loops that occur with the partial transformations. In this work the normal distribution model is extended to include the partial transformations that occur when the field is reversed before the transformation is complete. The resulting hysteresis loops produced by the model are in good agreement with the experimental results.

  8. Transformer design tradeoffs

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1977-01-01

    Technical memorandum includes transformer area product numbers, which are used to summarize dimensional and electrical properties of C-cores, pot cores, lamination, powder cores, and tape-wound cores. To aid in core selection, comparison of five common core materials is presented to indicate their influence on overall transformer efficiency and weight.

  9. Biochemical transformation of coals

    DOEpatents

    Lin, M.S.; Premuzic, E.T.

    1999-03-23

    A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed. 7 figs.

  10. Fourier Transform Spectrometer

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Understanding the global atmospheric changes is difficult with today's current technology. However, with high resolution and nearly continuous observations from a satellite, it's possible to transform our understanding of the atmosphere. To enable the next generation of atmospheric science, a new class of orbiting atmospheric sensors is being developed. The foundation of this advanced concept is the Fourier Transform Spectrometer, or FTS.

  11. Deployment & Market Transformation (Brochure)

    SciTech Connect

    Not Available

    2012-04-01

    NREL's deployment and market transformation (D and MT) activities encompass the laboratory's full range of technologies, which span the energy efficiency and renewable energy spectrum. NREL staff educates partners on how they can advance sustainable energy applications and also provides clients with best practices for reducing barriers to innovation and market transformation.

  12. Genetic Transformation of Bacteria.

    ERIC Educational Resources Information Center

    Moss, Robert.

    1991-01-01

    An activity in which students transform an ampicillin-sensitive strain of E. coli with a plasmid containing a gene for ampicillin resistance is described. The procedure for the preparation of competent cells and the transformation of competent E. coli is provided. (KR)

  13. Support Principals, Transform Schools

    ERIC Educational Resources Information Center

    Aguilar, Elena; Goldwasser, Davina; Tank-Crestetto, Kristina

    2011-01-01

    The Transformational Coaching Team in Oakland Unified School District provides differentiated, sustained, job-embedded support to the district's school leaders. In this article, members of the team describe how they work with principals to transform the culture of schools. Student achievement data show above-average improvement in schools in which…

  14. Two Different Squeeze Transformations

    NASA Technical Reports Server (NTRS)

    Han, D. (Editor); Kim, Y. S.

    1996-01-01

    Lorentz boosts are squeeze transformations. While these transformations are similar to those in squeezed states of light, they are fundamentally different from both physical and mathematical points of view. The difference is illustrated in terms of two coupled harmonic oscillators, and in terms of the covariant harmonic oscillator formalism.

  15. A Transformation Called "Twist"

    ERIC Educational Resources Information Center

    Hwang, Daniel

    2010-01-01

    The transformations found in secondary mathematics curriculum are typically limited to stretches and translations (e.g., ACARA, 2010). Advanced students may find the transformation, twist, to be of further interest. As most available resources are written for professional-level readers, this article is intended to be an introduction accessible to…

  16. Disc piezoelectric ceramic transformers.

    PubMed

    Erhart, Jirií; Půlpán, Petr; Doleček, Roman; Psota, Pavel; Lédl, Vít

    2013-08-01

    In this contribution, we present our study on disc-shaped and homogeneously poled piezoelectric ceramic transformers working in planar-extensional vibration modes. Transformers are designed with electrodes divided into wedge, axisymmetrical ring-dot, moonie, smile, or yin-yang segments. Transformation ratio, efficiency, and input and output impedances were measured for low-power signals. Transformer efficiency and transformation ratio were measured as a function of frequency and impedance load in the secondary circuit. Optimum impedance for the maximum efficiency has been found. Maximum efficiency and no-load transformation ratio can reach almost 100% and 52 for the fundamental resonance of ring-dot transformers and 98% and 67 for the second resonance of 2-segment wedge transformers. Maximum efficiency was reached at optimum impedance, which is in the range from 500 Ω to 10 kΩ, depending on the electrode pattern and size. Fundamental vibration mode and its overtones were further studied using frequency-modulated digital holographic interferometry and by the finite element method. Complementary information has been obtained by the infrared camera visualization of surface temperature profiles at higher driving power. PMID:25004532

  17. Transformative Learning and Identity

    ERIC Educational Resources Information Center

    Illeris, Knud

    2014-01-01

    Transformative learning has usually been defined as transformations of meaning perspectives, frames of reference, and habits of mind--as proposed initially by Jack Mezirow. However, several authors have found this definition too narrow and too cognitively oriented, and Mezirow has later emphasized that emotional and social conditions are also…

  18. Adaptive Wavelet Transforms

    SciTech Connect

    Szu, H.; Hsu, C.

    1996-12-31

    Human sensors systems (HSS) may be approximately described as an adaptive or self-learning version of the Wavelet Transforms (WT) that are capable to learn from several input-output associative pairs of suitable transform mother wavelets. Such an Adaptive WT (AWT) is a redundant combination of mother wavelets to either represent or classify inputs.

  19. Direct current transformer

    NASA Technical Reports Server (NTRS)

    Khanna, S. M.; Urban, E. W. (Inventor)

    1979-01-01

    A direct current transformer in which the primary consists of an elongated strip of superconductive material, across the ends of which is direct current potential is described. Parallel and closely spaced to the primary is positioned a transformer secondary consisting of a thin strip of magnetoresistive material.

  20. An extension of the Laplace transform to Schwartz distributions

    NASA Technical Reports Server (NTRS)

    Price, D. R.

    1974-01-01

    A characterization of the Laplace transform is developed which extends the transform to the Schwartz distributions. The class of distributions includes the impulse functions and other singular functions which occur as solutions to ordinary and partial differential equations. The standard theorems on analyticity, uniqueness, and invertibility of the transform are proved by using the characterization as the definition of the Laplace transform. The definition uses sequences of linear transformations on the space of distributions which extends the Laplace transform to another class of generalized functions, the Mikusinski operators. It is shown that the sequential definition of the transform is equivalent to Schwartz' extension of the ordinary Laplace transform to distributions but, in contrast to Schwartz' definition, does not use the distributional Fourier transform. Several theorems concerning the particular linear transformations used to define the Laplace transforms are proved. All the results proved in one dimension are extended to the n-dimensional case, but proofs are presented only for those situations that require methods different from their one-dimensional analogs.

  1. Transformer design tradeoffs

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1976-01-01

    Material was presented to assist transformer designers in the transition from long-used English units to the less familiar metric equivalents. A coordination between the area product numbers ap (product of window and core cross-section areas) and current density J was developed for a given regulation and temperature rise. Straight-line relationships for Ap and Volume, Ap and surface area At and, Ap and weight were developed. These relationships can now be used as new tools to simplify and standardize the process of transformer design. They also made it possible to design transformers of small bulk and volume or to optimize efficiency.

  2. Optical sine transformation.

    PubMed

    Yang, G; Zhang, J; Gong, J; Chen, J; Ho, Y

    1987-10-15

    The phase mask distribution of optical sine transformation (OST) has been calculated according to the optical general transformation theory. To avoid the diffraction loss of the phase mask, the optical waveguide method is used. Computation shows that the optical sine transformation is possible with only one phase mask, i.e., one-half of a cylindrical lens in the 1-D case and one-quarter of a spherical lens in the 2-D case. Experimental results agree with the theoretical prediction. Image compression by OST is also given. PMID:20523380

  3. Interfaith Dialogue as a Means for Transformational Conversations

    ERIC Educational Resources Information Center

    Krebs, Stephanie Russell

    2015-01-01

    This article reports findings, inspired by the researcher's personal, transformational experience, on students' responses to an interfaith dialogue at an Interfaith Youth Core Interfaith Leadership Institute. Results demonstrated that several factors characterize interfaith dialogue: the environment, individual relationships fostered through…

  4. Advances in the Natural transform

    NASA Astrophysics Data System (ADS)

    Belgacem, F. B. M.; Silambarasan, R.

    2012-11-01

    The literature review of the Natural transform and the existing definitions and connections to the Laplace and Sumudu transforms are discussed in this communication. Along with the complex inverse Natural transform and Heaviside's expansion formula, the relation of Bessel's function to Natural transform (and hence Laplace and Sumudu transforms) are defined.

  5. A discrete fractional random transform

    NASA Astrophysics Data System (ADS)

    Liu, Zhengjun; Zhao, Haifa; Liu, Shutian

    2005-11-01

    We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

  6. Martensitic nature of {delta} {yields} {gamma} allotropic transformation in plutonium

    SciTech Connect

    Lopez, P.C.; Cost, J.R.; Axler, K.M.

    1996-09-01

    Isothermal and isoplethal studies using differential scanning calorimetry have been conducted to characterize the allotropic transformations of plutonium. The {delta}-{gamma} transformation (upon cooling) was observed to have a classic martensitic nature. The work described herein is the first quantitative study of this phenomena in plutonium.

  7. A Classical Science Transformed.

    ERIC Educational Resources Information Center

    Kovalevsky, Jean

    1979-01-01

    Describes how satellites and other tools of space technology have transformed classical geodesy into the science of space geodynamics. The establishment and the activities of the French Center for Geodynamic and Astronomical Research Studies (CERGA) are also included. (HM)

  8. Transformer design tradeoffs

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1977-01-01

    In space, power system transformer components are frequently the heaviest and bulkiest items in the power conversion circuit. They also have a significant effect upon the overall performance and efficiency of the system. Accordingly, the design of such transformers has an important effect on overall system weight, power-inversion efficiency, and cost. Relationships were between the parameters used by transformer designers that can be used as new tools to standardize and simplify transformer design. They can be used to optimize the design either for small size and weight or efficiency. The metric system of units, rather than the familiar English units, is used; however, material is presented to assist the reader in the transition from one system to the other.

  9. Imaging Fourier transform spectrometer

    SciTech Connect

    Bennett, C.L.

    1993-09-13

    This invention is comprised of an imaging Fourier transform spectrometer having a Fourier transform infrared spectrometer providing a series of images to a focal plane array camera. The focal plane array camera is clocked to a multiple of zero crossing occurrences as caused by a moving mirror of the Fourier transform infrared spectrometer and as detected by a laser detector such that the frame capture rate of the focal plane array camera corresponds to a multiple of the zero crossing rate of the Fourier transform infrared spectrometer. The images are transmitted to a computer for processing such that representations of the images as viewed in the light of an arbitrary spectral ``fingerprint`` pattern can be displayed on a monitor or otherwise stored and manipulated by the computer.

  10. Fourier Transform Mass Spectrometry

    PubMed Central

    Scigelova, Michaela; Hornshaw, Martin; Giannakopulos, Anastassios; Makarov, Alexander

    2011-01-01

    This article provides an introduction to Fourier transform-based mass spectrometry. The key performance characteristics of Fourier transform-based mass spectrometry, mass accuracy and resolution, are presented in the view of how they impact the interpretation of measurements in proteomic applications. The theory and principles of operation of two types of mass analyzer, Fourier transform ion cyclotron resonance and Orbitrap, are described. Major benefits as well as limitations of Fourier transform-based mass spectrometry technology are discussed in the context of practical sample analysis, and illustrated with examples included as figures in this text and in the accompanying slide set. Comparisons highlighting the performance differences between the two mass analyzers are made where deemed useful in assisting the user with choosing the most appropriate technology for an application. Recent developments of these high-performing mass spectrometers are mentioned to provide a future outlook. PMID:21742802

  11. Fractals and Transformations.

    ERIC Educational Resources Information Center

    Bannon, Thomas J.

    1991-01-01

    Discussed are several different transformations based on the generation of fractals including self-similar designs, the chaos game, the koch curve, and the Sierpinski Triangle. Three computer programs which illustrate these concepts are provided. (CW)

  12. Proof in Transformation Geometry

    ERIC Educational Resources Information Center

    Bell, A. W.

    1971-01-01

    The first of three articles showing how inductively-obtained results in transformation geometry may be organized into a deductive system. This article discusses two approaches to enlargement (dilatation), one using coordinates and the other using synthetic methods. (MM)

  13. Increasing Immunization Compliance by Reducing Provisional Admittance

    ERIC Educational Resources Information Center

    Davis, Wendy S.; Varni, Susan E.; Barry, Sara E.; Frankowski, Barbara L.; Harder, Valerie S.

    2016-01-01

    Students in Vermont with incomplete or undocumented immunization status are provisionally admitted to schools and historically had a calendar year to resolve their immunization status. The process of resolving these students' immunization status was challenging for school nurses. We conducted a school-based quality improvement effort to increase…

  14. Nontensorial Transformation Optics

    NASA Astrophysics Data System (ADS)

    García-Meca, C.; Barceló, C.

    2016-06-01

    We present an alternative version of transformation optics that allows us to mold the flow of light without rotating or scaling the electromagnetic fields. The resulting media experience unusual force densities, are nonreciprocal, and exhibit loss or gain. Because of these singular features, a variety of effects and devices unreachable by standard transformation optics can be achieved, including reflectionless light compression, optical modes with arbitrary in-plane polarization, and special isolators.

  15. Series Transmission Line Transformer

    DOEpatents

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.

    2004-06-29

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  16. 25. VIEW, LOOKING SOUTHWEST INSIDE TRANSFORMER ROOM, SHOWING TRANSFORMERS AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. VIEW, LOOKING SOUTHWEST INSIDE TRANSFORMER ROOM, SHOWING TRANSFORMERS AND KNIFE SWITCHES - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  17. Floral Transformation of Wheat

    NASA Astrophysics Data System (ADS)

    Agarwal, Sujata; Loar, Star; Steber, Camille; Zale, Janice

    A method is described for the floral transformation of wheat using a protocol similar to the floral dip of Arabidopsis. This method does not employ tissue culture of dissected embryos, but instead pre-anthesis spikes with clipped florets at the early, mid to late uninucleate microspore stage are dipped in Agrobacterium infiltration media harboring a vector carrying anthocyanin reporters and the NPTII selectable marker. T1 seeds are examined for color changes induced in the embryo by the anthocyanin reporters. Putatively transformed seeds are germinated and the seedlings are screened for the presence of the NPTII gene based on resistance to paromomycin spray and assayed with NPTII ELISAs. Genomic DNA of putative transformants is digested and analyzed on Southern blots for copy number to determine whether the T-DNA has integrated into the nucleus and to show the number of insertions. The non-optimized transformation efficiencies range from 0.3 to 0.6% (number of transformants/number of florets dipped) but the efficiencies are higher in terms of the number of transformants produced/number of seeds set ranging from 0.9 to 10%. Research is underway to maximize seed set and optimize the protocol by testing different Agrobacterium strains, visual reporters, vectors, and surfactants.

  18. Development of a new transformant selection system for Penicillium chrysogenum: isolation and characterization of the P. chrysogenum acetyl-coenzyme A synthetase gene (facA) and its use as a homologous selection marker.

    PubMed

    Gouka, R J; van Hartingsveldt, W; Bovenberg, R A; van Zeijl, C M; van den Hondel, C A; van Gorcom, R F

    1993-01-01

    A new transformation system for the filamentous fungus Penicillium chrysogenum is described, based on the use of the homologous acetyl-coenzyme A synthetase (facA) gene as a selection marker. Acetate-non-utilizing (Fac-) strains of P. chrysogenum were obtained by positive selection for spontaneous resistance to fluoroacetate. Among these fac mutants putative facA strains were selected for a loss of acetyl-coenzyme A (CoA) synthetase activity. The facA gene, coding for the enzyme acetyl-CoA synthetase, was isolated from a P. chrysogenum genomic library using synthetic oligonucleotides derived from conserved regions from the corresponding genes of Aspergillus nidulans and Neurospora crassa. Vector pPC2-3, comprising a genomic 6.5 kb PstI fragment, was able to complement P. chrysogenum facA strains with frequencies up to 27 transformants.micrograms-1 DNA. Direct selection of transformants was accomplished using acetate and low amounts (0.001%) of glucose as carbon sources. About 50% of the transformants arose by integration of pPC2-3 DNA at the homologous facA locus and 50% by integration elsewhere in the genome. Determination of the nucleotide sequence of part of the cloned fragment showed the presence of an open reading frame of 2007 nucleotides, interrupted by five putative introns. Comparison of the nucleotide and the amino acid sequence of the facA gene of P. chrysogenum with the facA gene of A. nidulans reveals similarities of 80% and 89%, respectively. The putative introns present in the P. chrysogenum facA gene appear at identical positions as those in the A. nidulans facA gene, but show no significant sequence similarity. PMID:7765289

  19. Relativistic Transformation of Solid Angle.

    ERIC Educational Resources Information Center

    McKinley, John M.

    1980-01-01

    Rederives the relativistic transformations of light intensity from compact sources (stars) to show where and how the transformation of a solid angle contributes. Discusses astrophysical and other applications of the transformations. (Author/CS)

  20. Some Properties of Transforms in Cultural Theory

    NASA Astrophysics Data System (ADS)

    Ballonoff, Paul

    2010-12-01

    It is shown that, in certain circumstances, systems of cultural rules may be represented by doubly stochastic matrices denoted Π, called “possibility transforms,” and by certain real valued “possibility densities” π=( π 1, π 2,…, π n ) with inner product <π,πrangle=sumiπi2=1. We may characterize a certain problem of ethnographic or ethological description as a problem of prediction, in which observations are predicted by properties of fixed points of transforms of “pure systems”, or by properties of convex combinations of such “pure systems”. Other relationships to quantum methods are noted.

  1. General inversion formulas for wavelet transforms

    NASA Astrophysics Data System (ADS)

    Holschneider, Matthias

    1993-09-01

    This article is the continuation of a series of articles about group theory and wavelet analysis [A. Grossmann, J. Morlet, and T. Paul, J. Math. Phys. 26, 2473 (1985)]. As is well-known in the case of the afine group, the reconstruction wavelet and the analyzing wavelet need not be identic. In this article it is shown that this holds for arbitrary groups. In addition it is shown that even for nonadmissible analyzing wavelets the wavelet transform may be inverted. Accordingly the image of the wavelet transform can be characterized by many different reproducing kernels.

  2. A Characterization of the CH 2ã1A1(1,2,0),(2,0,0),(0,5,0),(1,3,0) and b˜1B1(1,14 2,0),(0,18 0,0),(0,19 1,0) Vibronic Levels by Fourier-Transform Dispersed Fluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Qin, D.; Hartland, G. V.; Dai, H. L.

    1994-12-01

    The CH2ã1A1, (1, 2, 0), (2, 0, 0), (0, 5, 0), (1, 3, 0) and b˜1B1 (1, 142, 0), (0, 180, 0), (0, 191, 0) levels are characterized by Fourier-transform dispersed fluorescence spectroscopy (FTDFS). Rotational transitions in the b˜ ← ã 1102140, 2180, and 2190 fluorescence excitation bands and those of the b˜ → ã 1012162, 1012172, 1022160, 2185, 2195, 1012183 and 1102193 bands in dispersed fluorescence spectra have been assigned. The rotational constants and vibrational term values for these vibrational levels have been obtained. Due to the limits brought by Renner-Teller coupling and Franck-Condon factors, this work, along with previous studies on lower vibrational levels, has characterized almost all ã vibrational levels detectable in the b˜↔ã transitions.

  3. Solid-state current transformer

    NASA Technical Reports Server (NTRS)

    Farnsworth, D. L. (Inventor)

    1976-01-01

    A signal transformation network which is uniquely characterized to exhibit a very low input impedance while maintaining a linear transfer characteristic when driven from a voltage source and when quiescently biased in the low microampere current range is described. In its simplest form, it consists of a tightly coupled two transistor network in which a common emitter input stage is interconnected directly with an emitter follower stage to provide virtually 100 percent negative feedback to the base input of the common emitter stage. Bias to the network is supplied via the common tie point of the common emitter stage collector terminal and the emitter follower base stage terminal by a regulated constant current source, and the output of the circuit is taken from the collector of the emitter follower stage.

  4. Martensitic transformation in zirconia

    SciTech Connect

    Deville, Sylvain . E-mail: sylvain.deville@insa-lyon.fr; Guenin, Gerard; Chevalier, Jerome

    2004-11-08

    We investigate by atomic force microscopy (AFM) the surface relief resulting from martensitic tetragonal to monoclinic phase transformation induced by low temperature autoclave aging in ceria-stabilized zirconia. AFM appears as a very powerful tool to investigate martensite relief quantitatively and with a great precision. The crystallographic phenomenological theory is used to predict the expected relief induced by the transformation, for the particular case of lattice correspondence ABC1, where tetragonal c axis becomes the monoclinic c axis. A model for variants spatial arrangement for this lattice correspondence is proposed and validated by the experimental observations. An excellent agreement is found between the quantitative calculations outputs and the experimental measurements at nanometer scale yielded by AFM. All the observed features are explained fully quantitatively by the calculations, with discrepancies between calculations and quantitative experimental measurements within the measurements and calculations precision range. In particular, the crystallographic orientation of the transformed grains is determined from the local characteristics of transformation induced relief. It is finally demonstrated that the strain energy is the controlling factor of the surface transformation induced by low temperature autoclave treatments in this material.

  5. Translating and Transforming Care

    PubMed Central

    Gillespie, Alex; Moore, Helen

    2015-01-01

    This article examines how the Disability Living Allowance claim form, used in the United Kingdom to allocate £13 billion of disability benefits, translates and transforms disability and care. Twenty-two people with acquired brain injury and their main informal caregivers (n = 44) were video-recorded filling in the disability claim form. Participants disagreed on 26% of the questions, revealing two types of problems. Translation problems arose as participants struggled to provide categorical responses to ambiguous questions and were unable to report contextual variability in care needs or divergences of perception. Transformation problems arose as participants resisted the way in which the form positioned them, forcing them to conceptualize their relationship in terms of dependency and burden. The disability claim form co-opts claimants to translate care and disability into bureaucratically predefined categories, and it transforms the care relationship that it purports to document. PMID:25792487

  6. Transformational plasmon optics.

    PubMed

    Liu, Yongmin; Zentgraf, Thomas; Bartal, Guy; Zhang, Xiang

    2010-06-01

    We propose and demonstrate efficiently molding surface plasmon polaritons (SPPs) based on transformation optics. SPPs are surface modes of electromagnetic waves tightly bound at metal-dielectric interfaces, which allow us to scale optics beyond the diffraction limit. Taking advantage of transformation optics, here we show that the propagation of SPPs can be manipulated in a prescribed manner by careful control of the dielectric material properties adjacent to a metal. Since the metal properties are completely unaltered, this methodology provides a practical way for routing light at very small scales. For instance, our approach enables SPPs to travel at uneven and curved surfaces over a broad wavelength range, where SPPs would normally suffer significant scattering losses. In addition, a plasmonic 180 degrees waveguide bend and a plasmonic Luneburg lens with simple designs are presented. The unique design flexibility of the transformational plasmon optics introduced here may open a new door to nano optics and downscaling of photonic circuits. PMID:20465268

  7. Transformation based endorsement systems

    NASA Technical Reports Server (NTRS)

    Sudkamp, Thomas

    1988-01-01

    Evidential reasoning techniques classically represent support for a hypothesis by a numeric value or an evidential interval. The combination of support is performed by an arithmetic rule which often requires restrictions to be placed on the set of possibilities. These assumptions usually require the hypotheses to be exhausitive and mutually exclusive. Endorsement based classification systems represent support for the alternatives symbolically rather than numerically. A framework for constructing endorsement systems is presented in which transformations are defined to generate and update the knowledge base. The interaction of the knowledge base and transformations produces a non-monotonic reasoning system. Two endorsement based reasoning systems are presented to demonstrate the flexibility of the transformational approach for reasoning with ambiguous and inconsistent information.

  8. Plastid transformation in soybean.

    PubMed

    Dubald, Manuel; Tissot, Ghislaine; Pelissier, Bernard

    2014-01-01

    The biotechnological potential of plastid genetic engineering has been illustrated in a limited number of higher plant species. We have developed a reproducible method to generate plastid transformants in soybean (Glycine max), a crop of major agronomic importance. The transformation vectors are delivered to embryogenic cultures by the particle gun method and selection performed using the aadA antibiotic resistance gene. Homoplasmy is established rapidly in the selected events without the need for further selection or regeneration cycles, and genes of interest can be expressed at a high level in green tissues. This is a significant step toward the commercial application of this technology. PMID:24599865

  9. Successful Transformational Radiology Leaders.

    PubMed

    Douget, Karen

    2015-01-01

    Transformational radiology leaders elevate subordinates, expand self-awareness, develop lasting relationships, strive to exceed expectations, and uphold the vision and goals of the organization. In order for radiology leaders to become more transformational in their leadership style there are four fundamental elements they must learn: idealized influence, individualized consideration, inspirational motivation, and intellectual stimulation. Leaders can utilize personality and self-assessments to learn more about themselves, identify areas of strengths and weaknesses, and learn to be more effective when leading employees. PMID:26710553

  10. Thermodynamic and structural characterization of the transformation from a metastable low-density to a very high-density form of supercooled TIP4P-Ew model water.

    PubMed

    Paschek, Dietmar; Rüppert, Andreas; Geiger, Alfons

    2008-12-22

    We explore the phase diagram of the metastable TIP4P-Ew liquid model water from 360 K down to 150 K at densities ranging from 0.950 to 1.355 g cm(-3). In addition to the low-density/high-density (LDL/HDL) liquid-liquid transition, we observe a structural high-density/very high-density (HDL/VHDL) transformation for the lowest temperatures at 1.30 g cm(-3). The characteristics of the isobars and isotherms suggest the presence of a stepwise HDL/VHDL transition with first-order-like appearance. In addition, we also identify an apparent pretransition at 1.24 g cm(-3), which suggests that the experimentally detected LDA/VHDA transformation might evolve into a multiple-step process with different local structures representing local minima in the free-energy landscape. Such a scenario is supported by a pronounced correlation between the isothermal density dependence of the pressure, with a stepwise increase of the oxygen coordination number, due to the appearance of interstitial water molecules. PMID:19035392

  11. Planar LTCC transformers for high voltage flyback converters.

    SciTech Connect

    Schofield, Daryl; Schare, Joshua M.; Glass, Sarah Jill; Roesler, Alexander William; Ewsuk, Kevin Gregory; Slama, George; Abel, Dave

    2007-06-01

    This paper discusses the design and use of low-temperature (850 C to 950 C) co-fired ceramic (LTCC) planar magnetic flyback transformers for applications that require conversion of a low voltage to high voltage (> 100V) with significant volumetric constraints. Measured performance and modeling results for multiple designs showed that the LTCC flyback transformer design and construction imposes serious limitations on the achievable coupling and significantly impacts the transformer performance and output voltage. This paper discusses the impact of various design factors that can provide improved performance by increasing transformer coupling and output voltage. The experiments performed on prototype units demonstrated LTCC transformer designs capable of greater than 2 kV output. Finally, the work investigated the effect of the LTCC microstructure on transformer insulation. Although this paper focuses on generating voltages in the kV range, the experimental characterization and discussion presented in this work applies to designs requiring lower voltage.

  12. Focus On: Transforming Relationships.

    ERIC Educational Resources Information Center

    Karal, Pearl; And Others

    1985-01-01

    Karal describes the psychodynamics by which children learn to fear and distrust long-term commitments. Vaines proposes a conceptualization of the home economist as transforming actor. LeBow addresses methods of treating obese youth. Fewster and Kuhonta offer insights on communicating with Third World rural women. (SK)

  13. Transforming Data into Knowledge

    ERIC Educational Resources Information Center

    Mills, Lane

    2006-01-01

    School systems can be data rich and information poor if they do not understand and manage their data effectively. The task for school leaders is to put existing data into a format that lends itself to answering questions and improving outcomes for the students. Common barriers to transforming data into knowledge in education settings often include…

  14. Transformative Mixed Methods Research

    ERIC Educational Resources Information Center

    Mertens, Donna M.

    2010-01-01

    Paradigms serve as metaphysical frameworks that guide researchers in the identification and clarification of their beliefs with regard to ethics, reality, knowledge, and methodology. The transformative paradigm is explained and illustrated as a framework for researchers who place a priority on social justice and the furtherance of human rights.…

  15. Fourier Transform Mass Spectrometry.

    ERIC Educational Resources Information Center

    Gross, Michael L.; Rempel, Don L.

    1984-01-01

    Discusses the nature of Fourier transform mass spectrometry and its unique combination of high mass resolution, high upper mass limit, and multichannel advantage. Examines its operation, capabilities and limitations, applications (ion storage, ion manipulation, ion chemistry), and future applications and developments. (JN)

  16. Transforming Primary Mathematics

    ERIC Educational Resources Information Center

    Askew, Mike

    2011-01-01

    What is good mathematics teaching? What is mathematics teaching good for? Who is mathematics teaching for? These are just some of the questions addressed in "Transforming Primary Mathematics", a highly timely new resource for teachers which accessibly sets out the key theories and latest research in primary maths today. Under-pinned by findings…

  17. Transforming Young Lives

    ERIC Educational Resources Information Center

    Larson, Scott

    2014-01-01

    Discussions of transformational change pervade the field of business but are rare in work with young people at risk--those most in need of deep change. Instead, the nation seems preoccupied with punishing or medicating problem behavior. Some propose the alternative of "rehabilitation," but that term means "to restore to former…

  18. Computerized toroidal transformer design

    NASA Technical Reports Server (NTRS)

    1970-01-01

    Computer program designs transformers which have one primary /center tap permissible/ and up to 20 untapped secondaries, and which can handle up to 500 V across any one winding. Computer determines total secondary power, core type, primary turns, secondary turns, and wire sizes for primary and secondary windings.

  19. Fixture for winding transformers

    NASA Technical Reports Server (NTRS)

    Mclyman, M. T.

    1980-01-01

    Bench-mounted fixture assists operator in winding toroid-shaped transformer cores. Toroid is rigidly held in place as wires are looped around. Arrangement frees both hands for rapid winding and untangling of wires that occurs when core is hand held.

  20. Transformer and Meter Tester

    NASA Technical Reports Server (NTRS)

    Stoms, R. M.

    1984-01-01

    Numerically-controlled 5-axis machine tool uses transformer and meter to determine and indicate whether tool is in home position, but lacks built-in test mode to check them. Tester makes possible test, and repair of components at machine rather then replace them when operation seems suspect.

  1. The fast Hartley transform

    NASA Astrophysics Data System (ADS)

    Mar, Mark H.

    1990-11-01

    The purpose of this paper is to report the results of testing the fast Hartley transform (FHT) and comparing it with the fast Fourier transform (FFT). All the definitions and equations in this paper are quoted and cited from the series of references. The author of this report developed a FORTRAN program which computes the Hartley transform. He tested the program with a generalized electromagnetic pulse waveform and verified the results with the known value. Fourier analysis is an essential tool to obtain frequency domain information from transient time domain signals. The FFT is a popular tool to process many of today's audio and electromagnetic signals. System frequency response, digital filtering of signals, and signal power spectrum are the most practical applications of the FFT. However, the Fourier integral transform of the FFT requires computer resources appropriate for the complex arithmetic operations. On the other hand, the FHT can accomplish the same results faster and requires fewer computer resources. The FHT is twice as fast as the FFT, uses only half the computer resources, and so could be more useful than the FFT in typical applications such as spectral analysis, signal processing, and convolution. This paper presents a FORTRAN computer program for the FHT algorithm along with a brief description and compares the results and performance of the FHT and the FFT algorithms.

  2. Teachers Transform Lives.

    ERIC Educational Resources Information Center

    Bradshaw, Delia

    2001-01-01

    Teachers transform lives, and the ripple effect goes on for years. Three pertinent questions are asked in this paper: Where does this power come from? What is its source? and What makes teachers so special? Two aspects of these questions are the multiplicity of identities that coexist within each teacher and the passion inside teachers that…

  3. Transformation Problem Solving Abilities.

    ERIC Educational Resources Information Center

    Harmel, Sarah Jane

    The relationship between transformation problem performance and Guilford Structure of Intellect (SI) abilities is explored. During two group sessions 42 females and 35 males, age 18-39, were administered 12 Guilford SI tests exemplifying all five symbolic content (numeric) operations, and three contents in the divergent production area. Logical…

  4. Leading System Transformation

    ERIC Educational Resources Information Center

    Harris, Alma

    2010-01-01

    This article outlines progress made towards education transformation in Wales. It explores the way in which tri-level reform is guiding system level change in Wales and looks at the implementation of the School Effectiveness Framework, which is at the heart of the reform process. It describes the way in which professional learning communities are…

  5. Dual Christoffel Transformations

    NASA Astrophysics Data System (ADS)

    Odake, S.; Sasaki, R.

    2011-07-01

    Crum's theorem and its modification à la Krein-Adler are formulated for the discrete quantum mechanics with real shifts, whose eigenfunctions consist of orthogonal polynomials of a discrete variable. The modification produces the associated polynomials with a finite number of degrees deleted. This in turn provides the well known Christoffel transformation for the dual orthogonal polynomials with the corresponding positions deleted.

  6. Global Transformations and Agriculture.

    ERIC Educational Resources Information Center

    Campbell, Rex R.

    1990-01-01

    Examines worldwide political, economic, and social transformations and their impact on agriculture, focusing on biotechnology. Discusses rise of international corporations and accompanying constraints on government power. Sees trend toward increasing agribusiness role in world food and agricultural sectors. Calls for broader views and research in…

  7. Winthrop College Transformed Curriculum.

    ERIC Educational Resources Information Center

    Hawisher, Margaret F.

    Dealing with the issue of a changing society and recognizing that teacher education has remained basically unchanged for 100 years, the faculty of the Winthrop College School of Education agreed to take the risk involved with transforming the teacher education curriculum. Three interdisciplinary teams have identified curriculum to be taught to…

  8. Transforming Education with Technology

    ERIC Educational Resources Information Center

    Scherer, Marge

    2011-01-01

    In this EL interview, Karen Cator, the director of the Office of Educational Technology at the U.S. Department of Education, talks about ways to realize the potential of technology to transform education. She discusses what students need: their own digital devices for classroom use, the ability to use the information they access, the skills to…

  9. Transformer Impedance Reflection Demonstration

    ERIC Educational Resources Information Center

    Layton, William

    2014-01-01

    Questions often arise as to how a device attached to a transformer can draw power from the electrical power grid since it seems that the primary and secondary are not connected to one another. However, a closer look at how the primary and secondary are linked together magnetically and a consideration of the role of Lenz's law in this linkage…

  10. Beyond Reform: Transformation

    ERIC Educational Resources Information Center

    Davidson, Jill

    2007-01-01

    The Coalition of Essential Schools (CES) is not a reform movement. To reform is to make a thing again; reformation implies a stasis that doesn't deliver enough for the educational future. This issue of Horace demonstrates that Essential schools and the districts and networks that support them are at various points in the journey of transformation,…

  11. Improved Transformation of Anthurium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods to increase transformation efficiency and yields of transgenic Anthurium andraeanum Linden ex. André hybrids were sought while effecting gene transfer for resistance to the two most important pests, bacterial blight (Xanthomonas axonopodis pv. dieffenbachiae) and nematodes (Radopholus simili...

  12. Transformative Change Initiative

    ERIC Educational Resources Information Center

    Bragg, D. D.; Kirby, C.; Witt, M. A.; Richie, D.; Mix, S.; Feldbaum, M.; Liu, S.; Mason, M.

    2014-01-01

    The Transformative Change Initiative (TCI) is dedicated to assisting community colleges to scale up innovation in the form of guided pathways, programs of study, and evidence-based strategies to improve student outcomes and program, organization, and system performance. The impetus for TCI is the Trade Adjustment Assistance Community College and…

  13. Transforming American Education

    ERIC Educational Resources Information Center

    Horn, Michael B.; Mackey, Katherine

    2011-01-01

    In this article the authors accept as a given the National Education Technology Plan's vision of a transformed education system powered by technology such that learners receive personalized and engaging learning experiences, and where assessment, teaching, infrastructure, and productivity are redefined. The article analyzes this vision of a…

  14. Residential market transformation: National and regional indicators

    SciTech Connect

    Van Wie McGrory, Laura L.; McNamara, Maureen; Suozzo, Margaret

    2000-06-01

    A variety of programs are underway to address market barriers to the adoption of energy-efficient residential technologies and practices. Most are administered by utilities, states, or regions that rely on the Energy Star as a consistent platform for program marketing and messaging. This paper reviews regional and national market transformation activities for three key residential end-uses -- air conditioning, clothes washing, and lighting -- characterizing current and ongoing programs; reporting on progress; identifying market indicators; and discussing implications.

  15. Wavelet transforms for optical pulse analysis.

    PubMed

    Vázquez, Javier Molina; Mazilu, Michael; Miller, Alan; Galbraith, Ian

    2005-12-01

    An exploration of wavelet transforms for ultrashort optical pulse characterization is given. Some of the most common wavelets are examined to determine the advantages of using the causal quasi-wavelet suggested in Proceedings of the LEOS 15th Annual Meeting (IEEE, 2002), Vol. 2, p. 592, in terms of pulse analysis and, in particular, chirp extraction. Owing to its ability to distinguish between past and future pulse information, the causal quasi-wavelet is found to be highly suitable for optical pulse characterization. PMID:16396051

  16. A study for designing YBCO power transformer

    NASA Astrophysics Data System (ADS)

    Hayashi, H.; Okamoto, H.; Harimoto, T.; Imayoshi, T.; Tomioka, A.; Bouno, T.; Konno, M.; Iwakuma, M.

    2007-10-01

    It is highly expected that superconducting transformers, which are characterized by incombustibility, light weight, and compactness, will be used practically for equipment in substations and office buildings sited in urban areas. In recent years, remarkable improvements in the performance of YBaCuO (YBCO) tape wire have been seen. This kind of tape wire has the property that its critical current is large in a highly magnetic field; and, its use is expected to reduce AC loss by applying slit processing on the tape wire, contributing to future cost reductions. In addition, the development of efficient, economical cryogenic units is also expected. The authors have developed a conceptual design for a 66 kV/20 MVA power transformer using YBCO tape wires, or an YBCO power transformer. As a result, we were able to identify the transformer's optimal system structure including coil winding comprised of coils and tape wires; and, we confirmed that the devised transformer can made to be both compact and highly efficient.

  17. Rainbow Fourier Transform

    NASA Technical Reports Server (NTRS)

    Alexandrov, Mikhail D.; Cairns, Brian; Mishchenko, Michael I.

    2012-01-01

    We present a novel technique for remote sensing of cloud droplet size distributions. Polarized reflectances in the scattering angle range between 135deg and 165deg exhibit a sharply defined rainbow structure, the shape of which is determined mostly by single scattering properties of cloud particles, and therefore, can be modeled using the Mie theory. Fitting the observed rainbow with such a model (computed for a parameterized family of particle size distributions) has been used for cloud droplet size retrievals. We discovered that the relationship between the rainbow structures and the corresponding particle size distributions is deeper than it had been commonly understood. In fact, the Mie theory-derived polarized reflectance as a function of reduced scattering angle (in the rainbow angular range) and the (monodisperse) particle radius appears to be a proxy to a kernel of an integral transform (similar to the sine Fourier transform on the positive semi-axis). This approach, called the rainbow Fourier transform (RFT), allows us to accurately retrieve the shape of the droplet size distribution by the application of the corresponding inverse transform to the observed polarized rainbow. While the basis functions of the proxy-transform are not exactly orthogonal in the finite angular range, this procedure needs to be complemented by a simple regression technique, which removes the retrieval artifacts. This non-parametric approach does not require any a priori knowledge of the droplet size distribution functional shape and is computationally fast (no look-up tables, no fitting, computations are the same as for the forward modeling).

  18. Phase transformations in binary colloidal monolayers.

    PubMed

    Yang, Ye; Fu, Lin; Marcoux, Catherine; Socolar, Joshua E S; Charbonneau, Patrick; Yellen, Benjamin B

    2015-03-28

    Phase transformations can be difficult to characterize at the microscopic level due to the inability to directly observe individual atomic motions. Model colloidal systems, by contrast, permit the direct observation of individual particle dynamics and of collective rearrangements, which allows for real-space characterization of phase transitions. Here, we study a quasi-two-dimensional, binary colloidal alloy that exhibits liquid-solid and solid-solid phase transitions, focusing on the kinetics of a diffusionless transformation between two crystal phases. Experiments are conducted on a monolayer of magnetic and nonmagnetic spheres suspended in a thin layer of ferrofluid and exposed to a tunable magnetic field. A theoretical model of hard spheres with point dipoles at their centers is used to guide the choice of experimental parameters and characterize the underlying materials physics. When the applied field is normal to the fluid layer, a checkerboard crystal forms; when the angle between the field and the normal is sufficiently large, a striped crystal assembles. As the field is slowly tilted away from the normal, we find that the transformation pathway between the two phases depends strongly on crystal orientation, field strength, and degree of confinement of the monolayer. In some cases, the pathway occurs by smooth magnetostrictive shear, while in others it involves the sudden formation of martensitic plates. PMID:25677504

  19. Transforming DNA uptake gene orthologs do not mediate spontaneous plasmid transformation in Escherichia coli.

    PubMed

    Sun, Dongchang; Zhang, Xuewu; Wang, Lingyu; Prudhomme, Marc; Xie, Zhixiong; Martin, Bernard; Claverys, Jean-Pierre

    2009-02-01

    Spontaneous plasmid transformation of Escherichia coli occurs on nutrient-containing agar plates. E. coli has also been reported to use double-stranded DNA (dsDNA) as a carbon source. The mechanism(s) of entry of exogenous dsDNA that allows plasmid establishment or the use of DNA as a nutrient remain(s) unknown. To further characterize plasmid transformation, we first documented the stimulation of transformation by agar and agarose. We provide evidence that stimulation is not due to agar contributing a supplement of Ca(2+), Fe(2+), Mg(2+), Mn(2+), or Zn(2+). Second, we undertook to inactivate the E. coli orthologues of Haemophilus influenzae components of the transformation machine that allows the uptake of single-stranded DNA (ssDNA) from exogenous dsDNA. The putative outer membrane channel protein (HofQ), transformation pseudopilus component (PpdD), and transmembrane pore (YcaI) are not required for plasmid transformation. We conclude that plasmid DNA does not enter E. coli cells as ssDNA. The finding that purified plasmid monomers transform E. coli with single-hit kinetics supports this conclusion; it establishes that a unique monomer molecule is sufficient to give rise to a transformant, which is not consistent with the reconstitution of an intact replicon through annealing of partially overlapping complementary ssDNA, taken up from two independent monomers. We therefore propose that plasmid transformation involves internalization of intact dsDNA molecules. Our data together, with previous reports that HofQ is required for the use of dsDNA as a carbon source, suggest the existence of two routes for DNA entry, at least across the outer membrane of E. coli. PMID:19011021

  20. How Political Science Became Modern: Racial Thought and the Transformation of the Discipline, 1880-1930

    ERIC Educational Resources Information Center

    Blatt, Jessica

    2009-01-01

    This dissertation argues that changing ideas about race and engagement with race science were at the heart of a major transformation of political science in the 1920s, a transformation that I characterize as "becoming modern." This transformation was at once conceptual--visible in the basic categories and theoretical apparatus of the…

  1. Reduction/Transformation Operators

    SciTech Connect

    Bartlett, Roscoe A.

    2006-09-01

    RTOp (reduction/transformation operators) is a collection of C++ software that provides the basic mechanism for implementinig vector operations in a flexible and efficient manner. This is the main interface utilized by Thyra to allow for the specification of specific vector reduction and/or transformation operations. The RTOp package contains three different types of software. (a) a small number of interoperability interfaces. (b) support software including code for the parallel SPMD mode based on only Teuchos::Comm(and not MPl directly(, and (c) a library of pre-implemented RTOp subclasses for everything from simple AXPYs and norms, to more specialized vector operations. RTOp allows an algorithm developer to implement their own RTOp subclasses in a way that is independent from any specific serial, parallel, out-of-core or other type of vector implementation. RTOp is a required package by Thyra and MOOCHO. (c)

  2. Transforming the optical landscape.

    PubMed

    Pendry, J B; Luo, Yu; Zhao, Rongkuo

    2015-05-01

    Electromagnetism provides us with some of the most powerful tools in science, encompassing lasers, optical microscopes, magnetic resonance imaging scanners, radar, and a host of other techniques. To understand and develop the technology requires more than a set of formal equations. Scientists and engineers have to form a vivid picture that fires their imaginations and enables intuition to play a full role in the process of invention. It is to this end that transformation optics has been developed, exploiting Faraday's picture of electric and magnetic fields as lines of force, which can be manipulated by the electrical permittivity and magnetic permeability of surrounding materials. Transformation optics says what has to be done to place the lines of force where we want them to be. PMID:25931549

  3. Dynamically tunable transformation thermodynamics

    NASA Astrophysics Data System (ADS)

    García-Meca, Carlos; Barceló, Carlos

    2016-04-01

    Recently, the introduction of transformation thermodynamics has provided a way to design thermal media that alter the flow of heat according to any spatial deformation, enabling the construction of novel devices such as thermal cloaks or concentrators. However, in its current version, this technique only allows static deformations of space. Here, we develop a space–time theory of transformation thermodynamics that incorporates the possibility of performing time-varying deformations. This extra freedom greatly widens the range of achievable effects, providing an additional degree of control for heat management applications. As an example, we design a reconfigurable thermal cloak that can be opened and closed dynamically, therefore being able to gradually adjust the temperature distribution of a given region.

  4. High voltage isolation transformer

    NASA Technical Reports Server (NTRS)

    Clatterbuck, C. H.; Ruitberg, A. P. (Inventor)

    1985-01-01

    A high voltage isolation transformer is provided with primary and secondary coils separated by discrete electrostatic shields from the surfaces of insulating spools on which the coils are wound. The electrostatic shields are formed by coatings of a compound with a low electrical conductivity which completely encase the coils and adhere to the surfaces of the insulating spools adjacent to the coils. Coatings of the compound also line axial bores of the spools, thereby forming electrostatic shields separating the spools from legs of a ferromagnetic core extending through the bores. The transformer is able to isolate a high constant potential applied to one of its coils, without the occurrence of sparking or corona, by coupling the coatings, lining the axial bores to the ferromagnetic core and by coupling one terminal of each coil to the respective coating encasing the coil.

  5. Transformation of Bacillus subtilis.

    PubMed

    Zhang, Xiao-Zhou; You, Chun; Zhang, Yi-Heng Percival

    2014-01-01

    Bacillus subtilis has tremendous applications in both academic research and industrial production. However, molecular cloning and transformation of B. subtilis are not as easy as those of Escherichia coli. Here we developed a simple protocol based on super-competent cells prepared from the recombinant B. subtilis strain SCK6 and multimeric plasmids generated by prolonged overlap extension-PCR. Super-competent B. subtilis SCK6 cells were prepared by overexpression of the competence master regulator ComK that was induced by adding xylose. This new protocol is simple (e.g., restriction enzyme, phosphatase, and ligase free), fast, and highly efficient (i.e., ~10(7) or ~10(4) transformants per μg of multimeric plasmid or ligated plasmid DNA, respectively). Shuttle vectors for E. coli-B. subtilis are not required. PMID:24838881

  6. A DC Transformer

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert C.; Ihlefeld, Curtis M.; Starr, Stanley O.

    2013-01-01

    A component level dc transformer is described in which no alternating currents or voltages are present. It operates by combining features of a homopolar motor and a homopolar generator, both de devices, such that the output voltage of a de power supply can be stepped up (or down) with a corresponding step down (or up) in current. The basic theory for this device is developed, performance predictions are made, and the results from a small prototype are presented. Based on demonstrated technology in the literature, this de transformer should be scalable to low megawatt levels, but it is more suited to high current than high voltage applications. Significant development would be required before it could achieve the kilovolt levels needed for de power transmission.

  7. Transforming the optical landscape

    NASA Astrophysics Data System (ADS)

    Pendry, J. B.; Luo, Yu; Zhao, Rongkuo

    2015-05-01

    Electromagnetism provides us with some of the most powerful tools in science, encompassing lasers, optical microscopes, magnetic resonance imaging scanners, radar, and a host of other techniques. To understand and develop the technology requires more than a set of formal equations. Scientists and engineers have to form a vivid picture that fires their imaginations and enables intuition to play a full role in the process of invention. It is to this end that transformation optics has been developed, exploiting Faraday’s picture of electric and magnetic fields as lines of force, which can be manipulated by the electrical permittivity and magnetic permeability of surrounding materials. Transformation optics says what has to be done to place the lines of force where we want them to be.

  8. Reduction/Transformation Operators

    Energy Science and Technology Software Center (ESTSC)

    2006-09-01

    RTOp (reduction/transformation operators) is a collection of C++ software that provides the basic mechanism for implementinig vector operations in a flexible and efficient manner. This is the main interface utilized by Thyra to allow for the specification of specific vector reduction and/or transformation operations. The RTOp package contains three different types of software. (a) a small number of interoperability interfaces. (b) support software including code for the parallel SPMD mode based on only Teuchos::Comm(and notmore » MPl directly(, and (c) a library of pre-implemented RTOp subclasses for everything from simple AXPYs and norms, to more specialized vector operations. RTOp allows an algorithm developer to implement their own RTOp subclasses in a way that is independent from any specific serial, parallel, out-of-core or other type of vector implementation. RTOp is a required package by Thyra and MOOCHO. (c)« less

  9. Bacterial transformation of terpenoids

    NASA Astrophysics Data System (ADS)

    Grishko, V. V.; Nogovitsina, Y. M.; Ivshina, I. B.

    2014-04-01

    Data on the bacterial transformation of terpenoids published in the literature in the past decade are analyzed. Possible pathways for chemo-, regio- and stereoselective modifications of terpenoids are discussed. Considerable attention is given to new technological approaches to the synthesis of terpenoid derivatives suitable for the use in the perfume and food industry and promising as drugs and chiral intermediates for fine organic synthesis. The bibliography includes 246 references.

  10. Transformer Impedance Reflection Demonstration

    NASA Astrophysics Data System (ADS)

    Layton, William

    2014-10-01

    Questions often arise as to how a device attached to a transformer can draw power from the electrical power grid since it seems that the primary and secondary are not connected to one another. However, a closer look at how the primary and secondary are linked together magnetically and a consideration of the role of Lenz's law in this linkage may help to clear up this confusion.

  11. Transforming revenue management.

    PubMed

    Silveria, Richard; Alliegro, Debra; Nudd, Steven

    2008-11-01

    Healthcare organizations that want to undertake a patient administrative/revenue management transformation should: Define the vision with underlying business objectives and key performance measures. Strategically partner with key vendors for business process development and technology design. Create a program organization and governance infrastructure. Develop a corporate design model that defines the standards for operationalizing the vision. Execute the vision through technology deployment and corporate design model implementation. PMID:18990839

  12. Laminated piezoelectric transformer

    NASA Technical Reports Server (NTRS)

    Vazquez Carazo, Alfredo (Inventor)

    2006-01-01

    A laminated piezoelectric transformer is provided using the longitudinal vibration modes for step-up voltage conversion applications. The input portions are polarized to deform in a longitudinal plane and are bonded to an output portion. The deformation of the input portions is mechanically coupled to the output portion, which deforms in the same longitudinal direction relative to the input portion. The output portion is polarized in the thickness direction relative its electrodes, and piezoelectrically generates a stepped-up output voltage.

  13. Function transformation without reinforcement.

    PubMed

    Tonneau, Franćois; Arreola, Fara; Martínez, Alma Gabriela

    2006-05-01

    In studies of function transformation, participants initially are taught to match stimuli in the presence of a contextual cue, X; the stimuli to be matched bear some formal relation to each other, for example, a relation of opposition or difference. In a second phase, the participants are taught to match arbitrary stimuli (say, A and B) in the presence of X. In a final test, A often displays behavioral functions that differ from those of B, and can be predicted from the nature of the relation associated with X in the initial training phase. Here we report function-transformation effects in the absence of selection responses and of their reinforcers. In three experiments with college students, exposure to relations of difference or identity modified the responses given to later stimuli. In Experiment 1, responses to a test stimulus A varied depending on preexposure to pairs of colors that were distinct from A but exemplified relations of difference or identity. In Experiment 2, a stimulus A acquired distinct functions, depending on its previous pairing with a contextual cue X that had itself been paired with identity or difference among colors. Experiment 3 confirmed the results of Experiment 2 with a modified design. Our data are consistent with the notion that relations of identity or difference can serve as stimuli for Pavlovian processes, and, in compound with other cues, produce apparent function-transformation effects. PMID:16776058

  14. Function Transformation without Reinforcement

    PubMed Central

    Tonneau, François; Arreola, Fara; Martínez, Alma Gabriela

    2006-01-01

    In studies of function transformation, participants initially are taught to match stimuli in the presence of a contextual cue, X; the stimuli to be matched bear some formal relation to each other, for example, a relation of opposition or difference. In a second phase, the participants are taught to match arbitrary stimuli (say, A and B) in the presence of X. In a final test, A often displays behavioral functions that differ from those of B, and can be predicted from the nature of the relation associated with X in the initial training phase. Here we report function-transformation effects in the absence of selection responses and of their reinforcers. In three experiments with college students, exposure to relations of difference or identity modified the responses given to later stimuli. In Experiment 1, responses to a test stimulus A varied depending on preexposure to pairs of colors that were distinct from A but exemplified relations of difference or identity. In Experiment 2, a stimulus A acquired distinct functions, depending on its previous pairing with a contextual cue X that had itself been paired with identity or difference among colors. Experiment 3 confirmed the results of Experiment 2 with a modified design. Our data are consistent with the notion that relations of identity or difference can serve as stimuli for Pavlovian processes, and, in compound with other cues, produce apparent function-transformation effects. PMID:16776058

  15. Transforming the dilemma

    PubMed Central

    Taylor, Christine; Nowak, Martin A.

    2008-01-01

    How does natural selection lead to cooperation between competing individuals? The Prisoner's Dilemma captures the essence of this problem. Two players can either cooperate or defect. The payoff for mutual cooperation, R, is greater than the payoff for mutual defection, P. But a defector versus a cooperator receives the highest payoff, T, while the cooperator obtains the lowest payoff, S. Hence, the Prisoner's Dilemma is defined by the payoff ranking T > R > P > S. In a well-mixed population, defectors always have a higher expected payoff than cooperators, and therefore natural selection favors defectors. The evolution of cooperation requires specific mechanisms. Here we discuss five mechanisms for the evolution of cooperation: direct reciprocity, indirect reciprocity, kin selection, group selection and network reciprocity (or graph selection). Each mechanism leads to a transformation of the Prisoner's Dilemma payoff matrix. From the transformed matrices, we derive the fundamental conditions for the evolution of cooperation. The transformed matrices can be used in standard frameworks of evolutionary dynamics such as the replicator equation or stochastic processes of game dynamics in finite populations. PMID:17711471

  16. The theory of transformations and autistic states. Autistic transformations: a proposal.

    PubMed

    Fix Korbivcher, Celia

    2005-12-01

    This work integrates two areas of thinking: one in which the author develops considerations regarding observation methods of mental phenomena in psychoanalysis according to Bion's theory of transformations; the other in which she is concerned with the investigation of primitive mental states--protomental states--more specifically, the autistic states of neurotic patients, described by Tustin. Some ideas on the 'philosophical' position underlying transformations theory are elaborated, particularly emphasizing the idea that the same phenomenon in psychoanalysis may be considered from different perspectives, as long as it is situated within the theoretical reference frame to which it belongs. The author considers the idea that this method of phenomenon observation is part of a wider context of general human knowledge, in which uncertainty and relativity of concepts are the main components. By adopting transformations theory as a perspective of phenomena observation that pervades the analytical meeting, the author questions whether it is possible to include other groups of transformation of emotional experiences in this theory, which shows particular phenomena with specific qualities, distinct from those emphasized by Bion. She hypothesizes that autistic phenomena present in neurotic patients, characterizing autistic states, may be considered and detached, making up a particular group of transformation of emotional experience, which analysts often face in their daily practice. She names this group 'autistic transformations'. PMID:16318939

  17. 60. VIEW OF THE CURRENT TRANSFORMER VAULT. THIS CURRENT TRANSFORMER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    60. VIEW OF THE CURRENT TRANSFORMER VAULT. THIS CURRENT TRANSFORMER WAS USED TO SENSE HIGH CURRENT BEING GENERATED ON GENERATOR NUMBER 3 AND REDUCE IT TO A LOWER, EXACT ANALOG VALUE THAT COULD BE SAFELY HANDLED AND MONITORED WITH THE CONTROL CIRCUITRY. THE CURRENT TRANSFORMER IS LOCATED IN THE CENTER OF THE PHOTOGRAPH. THE CONNECTING BUS ABOVE THE TRANSFORMER WAS REMOVED FOR SALVAGE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

  18. 134. VIEW OF TRANSFORMER CABINETS ON NORTH SIDE OF TRANSFORMER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    134. VIEW OF TRANSFORMER CABINETS ON NORTH SIDE OF TRANSFORMER ROOM (212), LSB (BLDG. 751), FACING SOUTH. POWER PANEL B AT EAST SIDE OF TRANSFORMER ROOM (212), FACING WEST, AT RIGHT IN PHOTOGRAPH. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  19. Microbial Transformation of TRU and Mixed Wastes: Actinide Speciation and Waste Volume Reduction

    SciTech Connect

    Halada, Gary P.

    2004-12-01

    I. To characterize the biodegradation of cellulosic materials using Fourier Transform Infrared (FTIR) Spectroscopy. II. To develop an electrochemical/spectroscopic methodology to characterize TRU waste microbial transformation III. To develop molecular models of TRU complexes in order to understand microbial transformation In all cases, objectives are designed to compliment the efforts from other team members, and will be periodically coordinated through the lead P.I. at Brookhaven National Laboratory (BNL), A.J. Francis.

  20. Fabrication and characterization of Na0.5K0.5NbO3-CuNb2O6 lead-free step-down piezoelectric transformers

    NASA Astrophysics Data System (ADS)

    Yang, Ming-Ru; Chu, Sheng-Yuan; Chan, I.-Hao; Huang, Sheng-Kai

    2011-08-01

    Lead-free (Na0.5K0.5)NbO3 (NKN) ceramics doped with 1 mol% CuNb2O6 (01CN) ceramics were prepared using the conventional mixed oxide method at a sintering temperature of 1075 °C. NKN + 1 mol% CuTa2O6 (NKN-01CN) ceramics sintered at 1075 °C exhibit excellent "hard" piezoelectric properties of kp = 40%, kt = 45%, and k33 = 57%, with ferroelectric property Ec = 23 kV/cm. The mechanical quality factor (Qm) is extraordinarily high (1933) and the temperature stability is excellent (Temperature coefficient of frequency (TCF) = -154 ppm/°C). The piezoelectric transformer (PT) was fabricated on NKN-01CN lead-free substrates, and the electrical characteristics were investigated. The devices were simplified into an equivalent circuit and analyzed using the MATLAB software package. The simulation results matched the experimental results. By reversing the input and the output, the step-down PT can be easily fabricated using a simple disk-type structure. A maximum efficiency of 93% with a voltage gain of 0.12 was measured, which was in good agreement with the simulation results (a maximum efficiency of 98.7% with a voltage gain of 0.13) for the step-down mode.

  1. RECENT ADVANCES IN BARLEY TRANSFORMATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley, an important member of the cereals, has been successfully transformed through various methods such as particle bombardment, Agrobacterium-tumefaciens, DNA uptake, and electroporation. Initially, the transformation in barley concentrated on developing protocols using marker genes such as gus,...

  2. The Transformation of Disabilities Organizations

    ERIC Educational Resources Information Center

    Schalock, Robert L.; Verdugo, Miguel-Angel

    2013-01-01

    This article summarizes the five major characteristics of the transformation era and describes how intellectual and closely related developmental disabilities organizations can apply specific transformation strategies associated with each characteristic. Collectively, the characteristics and strategies provide a framework for transformation…

  3. Transformational Leadership, Integrity, and Power

    ERIC Educational Resources Information Center

    Harrison, Laura M.

    2011-01-01

    Transformational leadership enjoys widespread appeal among student affairs professionals. National Association of Student Personnel Administrators (NASPA) and American College Personnel Association (ACPA) conferences frequently feature speakers who promote transformational leadership's two primary tenets: (1) change is the central purpose of…

  4. Mineralogical transformations controlling acid mine drainage chemistry

    SciTech Connect

    Peretyazhko, Tetyana; Zachara, John M.; Boily, Jean F.; Xia, Yuanxian; Gassman, Paul L.; Arey, Bruce W.; Burgos, William D.

    2009-05-30

    The role of Fe(III) minerals in controlling acid mine drainage (AMD) chemistry was studied using samples from two AMD sites [Gum Boot (GB) and Fridays-2 (FR)] located in northern Pennsylvania. Chemical extractions, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were used to identify and characterize Fe(III) phases. The mineralogical analysis revealed that schwertmannite and goethite were the principal Fe(III) phases in the sediments. Schwertmannite transformation occurred at the GB site where poorly-crystallized goethite rich in surface-bound sulfate was initially formed. In contrast, no schwertmannite transformation occurred at the FR site. The goethite in GB sediments had spherical morphology due to preservation of schwertmannite structure by adsorbed sulfate. Results of chemical extractions showed that poorly-crystallized goethite was subject to further crystallization accompanied by sulfate desorption. Changes in sulfate speciation preceded its desorption, with a conversion of bidentate- to monodentate-bound sulfate surface complexes. Laboratory sediment incubation experiments were conducted to evaluate the effect of mineral transformation on water chemistry. Incubation experiments were carried out with schwertmannite-containing sediments and AMD waters with different pH and chemical composition. The pH decreased to 1.9-2.2 in all suspensions and the concentrations of dissolved Fe and S increased significantly. Regardless of differences in the initial water composition, pH, Fe and S were similar in suspensions of the same sediment. XRD measurements revealed that schwertmannite transformed into goethite in GB and FR sediments during laboratory incubation. The incubation experiment demonstrated that schwertmannite transformation controlled AMD water chemistry during “closed system” laboratory contact.

  5. Thin-Film Power Transformers

    NASA Technical Reports Server (NTRS)

    Katti, Romney R.

    1995-01-01

    Transformer core made of thin layers of insulating material interspersed with thin layers of ferromagnetic material. Flux-linking conductors made of thinner nonferromagnetic-conductor/insulator multilayers wrapped around core. Transformers have geometric features finer than those of transformers made in customary way by machining and mechanical pressing. In addition, some thin-film materials exhibit magnetic-flux-carrying capabilities superior to those of customary bulk transformer materials. Suitable for low-cost, high-yield mass production.

  6. Canonical Transformations of Kepler Trajectories

    ERIC Educational Resources Information Center

    Mostowski, Jan

    2010-01-01

    In this paper, canonical transformations generated by constants of motion in the case of the Kepler problem are discussed. It is shown that canonical transformations generated by angular momentum are rotations of the trajectory. Particular attention is paid to canonical transformations generated by the Runge-Lenz vector. It is shown that these…

  7. Enhancing Understanding of Transformation Matrices

    ERIC Educational Resources Information Center

    Dick, Jonathan; Childrey, Maria

    2012-01-01

    With the Common Core State Standards' emphasis on transformations, teachers need a variety of approaches to increase student understanding. Teaching matrix transformations by focusing on row vectors gives students tools to create matrices to perform transformations. This empowerment opens many doors: Students are able to create the matrices for…

  8. Teacher Transformation: Transcending Hegemonic Roots

    ERIC Educational Resources Information Center

    Peters, Gregory

    2012-01-01

    In this dissertation study, I build from the research on transformative teaching (transformative for students), liberating theories (Liberating, Liberation and Liberating Theories) as well as literature about transformation, reflection and discourse to make the case that our historic and continuously inequitable results for students based on…

  9. Quality as Transformation: Educational Metamorphosis

    ERIC Educational Resources Information Center

    Cheng, Ming

    2014-01-01

    The notion of "quality as transformation" has been widely used in the higher education sector. However, both quality and transformation are elusive terms. There is little research exploring how quality could be equated to transformation in the learning process. This paper will provide an insight into the relationship between quality and…

  10. The transformation of disabilities organizations.

    PubMed

    Schalock, Robert L; Verdugo, Miguel-Angel

    2013-08-01

    This article summarizes the five major characteristics of the transformation era and describes how intellectual and closely related developmental disabilities organizations can apply specific transformation strategies associated with each characteristic. Collectively, the characteristics and strategies provide a framework for transformation thinking, learning, and acting. Specific application examples are given. PMID:23909588

  11. An Interplay Between Infrared Multiphoton Dissociation Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry and Density Functional Theory Computations in the Characterization of a Tripodal Quinolin-8-Olate Gd(III) Complex

    NASA Astrophysics Data System (ADS)

    De Bonis, Margherita; Bianco, Giuliana; Amati, Mario; Belviso, Sandra; Cataldi, Tommaso R. I.; Lelj, Francesco

    2013-04-01

    A new hexadentate, tripodal 8-hydroxyquinoline based ligand (QH3) and its gadolinium(III) tris-chelated (GdQ) complex with hemicage structure was investigated by using high resolution Fourier-transform ion cyclotron resonance mass spectrometry (FTICRMS). The protonated adduct of the free ligand and its hemicage tripodal Gd(III) complex, [GdQ + H]+, were first observed in experiments of electrospray ionization (ESI) with a linear ion trap (LTQ) mass spectrometer and further investigated by using high resolution FTICRMS. Gas-phase dissociation of the protonated Gd(III) complex, by infrared multiphoton dissociation (IRMPD) FTICR MS, demonstrated a fragmentation pattern with six main product cluster ions labeled as [Fn]+ ( n = 1 up to 6). These product ions suggest the elimination of 7-amino-alkyl or 7-alkyl chains of the hemicage moiety. High resolution MS conditions allowed the elucidation of the fragmentation pattern and product ion structures along with the determination, among the isotopic pattern of Gd, of the chemical compositions of closely related species, which differ in terms of hydrogen content. Among the Gd six naturally stable isotopes, 158Gd is the most abundant, and its peak within each cluster was used as a reference for distinguishing each product ions. Computational DFT investigations were applied to give support to some hypothesis of fragmentation pathways, which could not have been easily justified on the basis of the experimental work. Furthermore, computational studies suggested the coordination geometry of the protonated parent complex and the five- and four-coordinated complexes, which derive from its fragmentation. Furthermore, experimental and computational evidences were collected about the octet spin state of the parent compound.

  12. Banded transformer cores

    NASA Technical Reports Server (NTRS)

    Mclyman, C. W. T. (Inventor)

    1974-01-01

    A banded transformer core formed by positioning a pair of mated, similar core halves on a supporting pedestal. The core halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the core edge for reducing the innate air gap. A dc magnetic field is employed in supporting the core halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.

  13. Thermal energy transformer

    NASA Technical Reports Server (NTRS)

    Berdahl, C. M.; Thiele, C. L. (Inventor)

    1979-01-01

    For use in combination with a heat engine, a thermal energy transformer is presented. It is comprised of a flux receiver having a first wall defining therein a radiation absorption cavity for converting solar flux to thermal energy, and a second wall defining an energy transfer wall for the heat engine. There is a heat pipe chamber interposed between the first and second walls having a working fluid disposed within the chamber and a wick lining the chamber for conducting the working fluid from the second wall to the first wall. Thermal energy is transferred from the radiation absorption cavity to the heat engine.

  14. Evaluate and characterize mechanisms controlling transport, fate and effects of army smokes in an aerosol wind tunnel: Transport, transformations, fate and terrestrial ecological effects of fog oil obscurant smokes: Final report

    SciTech Connect

    Cataldo, D.A.; Van Voris, P.; Ligotke, M.W.; Fellows, R.J.; McVeety, B.D.; Li, Shu-mei W.; Bolton, H. Jr.; Fredrickson, J.K.

    1989-01-01

    The terrestrial transport, chemical fate, and ecological effects of fog oil (FO) smoke obscurants were evaluated under controlled wind tunnel conditions. The primary objectives of this research program are to characterize and assess the impacts of smoke and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of soils representative of these training sites; and (3) soil microbiological and invertebrate communities. Impacts and dose/responses were evaluated based on an exposure scenario, including exposure duration, exposure rate, and sequential cumulative dosing. Key to understanding the environmental impacts of fog oil smoke/obscurants is establishing the importance of environmental parameters, such as relative humidity and wind speed on airborne aerosol characteristics and deposition to receptor surfaces. Direct and indirect biotic effects were evaluated using five plant species and three soil types. 29 refs., 35 figs., 32 tabs.

  15. Computer simulation of martensitic transformations

    SciTech Connect

    Xu, Ping

    1993-11-01

    The characteristics of martensitic transformations in solids are largely determined by the elastic strain that develops as martensite particles grow and interact. To study the development of microstructure, a finite-element computer simulation model was constructed to mimic the transformation process. The transformation is athermal and simulated at each incremental step by transforming the cell which maximizes the decrease in the free energy. To determine the free energy change, the elastic energy developed during martensite growth is calculated from the theory of linear elasticity for elastically homogeneous media, and updated as the transformation proceeds.

  16. Transformational silicon electronics.

    PubMed

    Rojas, Jhonathan Prieto; Torres Sevilla, Galo Andres; Ghoneim, Mohamed Tarek; Inayat, Salman Bin; Ahmed, Sally M; Hussain, Aftab Mustansir; Hussain, Muhammad Mustafa

    2014-02-25

    In today's traditional electronics such as in computers or in mobile phones, billions of high-performance, ultra-low-power devices are neatly integrated in extremely compact areas on rigid and brittle but low-cost bulk monocrystalline silicon (100) wafers. Ninety percent of global electronics are made up of silicon. Therefore, we have developed a generic low-cost regenerative batch fabrication process to transform such wafers full of devices into thin (5 μm), mechanically flexible, optically semitransparent silicon fabric with devices, then recycling the remaining wafer to generate multiple silicon fabric with chips and devices, ensuring low-cost and optimal utilization of the whole substrate. We show monocrystalline, amorphous, and polycrystalline silicon and silicon dioxide fabric, all from low-cost bulk silicon (100) wafers with the semiconductor industry's most advanced high-κ/metal gate stack based high-performance, ultra-low-power capacitors, field effect transistors, energy harvesters, and storage to emphasize the effectiveness and versatility of this process to transform traditional electronics into flexible and semitransparent ones for multipurpose applications. PMID:24476361

  17. Image Transformations-Montserrat

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A slightly oblique digital photograph of Montserrat taken from the International Space Station was posted to Earth Observatory in December 2001. An Earth Observatory reader used widely available software to correct the oblique perspective and adjust the color. The story of how he modified the image includes step-by-step instructions that can be applied to other photographs. Photographs of Earth taken by astronauts have shaped our view of the Earth and are part of our popular culture because NASA makes them easily accessible to the public. Read the Transformations Story for more information. The original image was digital photograph number ISS002-E-9309, taken on July 9, 2001, from the International Space Station and was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth. Bill Innanen provided the transformed image and the story of how he did it.

  18. Characterization of transforming growth factor-beta (TGF-beta) receptors on BeWo choriocarcinoma cells including the identification of a novel 38-kDa TGF-beta binding glycoprotein.

    PubMed Central

    Mitchell, E J; Lee, K; O'Connor-McCourt, M D

    1992-01-01

    Transforming growth factor-beta (TGF-beta) is a potential mediator of placental trophoblast functions, including differentiation, hormone production, endometrial invasion, and immunosuppression. Equilibrium binding and affinity-labeling assays were used to investigate the binding characteristics of TGF-beta 1 and TGF-beta 2 on an established human choriocarcinoma trophoblastic cell line (BeWo). The equilibrium binding experiments indicated that the BeWo cells exhibited similar average affinities and total number of binding sites for TGF-beta 1 and TGF-beta 2. The Kd values obtained from Scatchard analyses were approximately 65 pM for 125I-TGF-beta 1 and approximately 40 pM for 125I-TGF-beta 2, with 70,000 and 85,000 sites per cell, respectively. Competitive equilibrium binding experiments indicated that TGF-beta 1 and TGF-beta 2 were equipotent (apparent half maximal inhibition [IC50] approximately 70 pM) and that all binding sites were capable of recognizing both isoforms. Affinity-labeling studies with 125I-TGF-beta 1 and 125I-TGF-beta 2 and the chemical cross-linking agent bis(sulfosuccinimidyl)suberate (BS3) revealed a predominant type III/betaglycan receptor, a low level of apparently heterogeneous type I and II receptors and an additional novel 38-kDa TGF-beta binding glycoprotein that was present both under reducing and nonreducing conditions on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Affinity-labeling saturation and competition studies indicated that the type III/betaglycan component appears to have a 7-fold higher capacity for TGF-beta 1 than for -beta 2 yet exhibits a 5- to 10-fold higher affinity for TGF-beta 2 than for -beta 1. The 38-kDa TGF-beta binding component, an N-linked glycoprotein, exhibits a higher affinity for TGF-beta 2 than for -beta 1 that is strikingly similar to that of the type III/betaglycan receptor. This 38-kDa binding protein appears to be upregulated after methotrexate-induced differentiation of the

  19. Transformations of emotional experience.

    PubMed

    de Cortiñas, Lia Pistiner

    2013-06-01

    In this paper the author approaches mental pain and the problems in a psychoanalytic treatment of patients with difficulties in the psychic transformation of their emotional experiences. The author is interested in the symbolic failure related to the obstruction of development of phantasies, dreams, dream-thoughts, etc. She differentiates symbolization disturbances related to hypertrophic projective identification from a detention of these primitive communications and emotional isolation. She puts forward the conjecture that one factor in the arrest of this development is the detention of projective identifications and that, when this primitive means of communication is re-established in a container-contained relationship of mutual benefit, this initiates the development of a symbolization process that can replace the pathological 'protection'. Another hypothesis she develops is that of inaccessible caesuras that, associated with the detention of projective identification, obstruct any integrative or interactive movement. This caesura and the detention of projective identifications affect mental functions needed for dealing with mental pain. The personality is left with precarious mental equipment for transforming emotional experiences. How can a psychoanalytical process stimulate the development of creative symbolization, transforming the emotional experiences and leading towards mental growth? The author approaches the clinical problem with the metaphor of the psychic birth of emotional experience. The modulation of mental pain in a container-contained relationship is a central problem for the development of the human mind. For discovering and giving a meaning to emotional experience, the infant depends on reverie, a function necessary in order to develop an evolved consciousness capable of being aware, which is different from the rudimentary consciousness that perceives but does not understand. The development of mature mental equipment is associated with the

  20. Recent advances in plant transformation.

    PubMed

    Barampuram, Shyamkumar; Zhang, Zhanyuan J

    2011-01-01

    Plant genetic engineering has become one of the most important molecular tools in the modern molecular breeding of crops. Over the last decade, significant progress has been made in the development of new and efficient transformation methods in plants. Despite a variety of available DNA delivery methods, Agrobacterium- and biolistic-mediated transformation remain the two predominantly employed approaches. In particular, progress in Agrobacterium-mediated transformation of cereals and other recalcitrant dicot species has been quite remarkable. In the meantime, other transgenic-enabling technologies have emerged, including generation of marker-free transgenics, gene targeting, and chromosomal engineering. Although transformation of some plant species or elite germplasm remains a challenge, further advancement in transformation technology is expected because the mechanisms of governing the regeneration and transformation processes are now better understood and are being creatively applied to designing improved transformation methods or to developing new enabling technologies. PMID:21181522

  1. Physical characterization of cadmium telluride/cadmium sulfide photovoltaics: Defects, fields, and micrononuniformities

    NASA Astrophysics Data System (ADS)

    Shvydka, Diana

    Recent advances in large area thin-film photovoltaic manufacturing have raised a number of problems related to the physical parameters and processes behind the device efficiency and stability. The characteristics of interest include the defect spectra and related optical absorption, the built-in electric field distribution, the degree of lateral uniformity of the device, and the device stability. Established in this thesis is a set of techniques appropriate for the physical characterization of the above features in CdTe/CdS solar cells, addressing the issues of device spectra vs. energy (as revealed in the optical absorption, photoluminescence (PL), and admittance spectroscopy); the electric field distribution analyzed by means of bias dependent PL, and, indirectly, by capacitance measurements; device lateral resistivity and uniformity, through the phenomenon of nonlocal optical response and PL mapping; local parameter fluctuations as appear in virtually all of the above cases. The most important physical conclusions made are: energy spectra of polycrystalline CdTe based photovoltaics combine the features of crystalline materials, such as identifiable point defects, and amorphous materials, which exhibit continuous spectra of localized states; the concept of a single-defect (elemental) capacitance is for the first time defined and applied to estimate the density of states in polycrystalline p-n junctions; a phenomenon of bias-dependent PL in CdTe based photovoltaics is for the first time observed and modeled; a new phenomenon of nonlocal photovoltaic response is observed and interpreted. The results suggest several practical applications, such as: absorption and PL measurements as a diagnostic tool for monitoring the CdCl2, quality of treatments; admittance spectroscopy techniques to diagnose the material quality and degradation through its defect spectra and concentration; bias-dependent PL as a sensitive nondestructive accelerated life testing tool; nonlocal PV

  2. Metasurface transformation for surface wave control.

    PubMed

    Martini, E; Mencagli, M; Maci, S

    2015-08-28

    Metasurfaces (MTSs) constitute a class of thin metamaterials used for controlling plane waves and surface waves (SWs). At microwave frequencies, they are constituted by a metallic texture with elements of sub-wavelength size printed on thin grounded dielectric substrates. These structures support the propagation of SWs. By averaging the tangential fields, the MTSs can be characterized through homogenized isotropic or anisotropic boundary conditions, which can be described through a homogeneous equivalent impedance. This impedance can be spatially modulated by locally changing the size/orientation of the texture elements. This allows for a deformation of the SW wavefront which addresses the local wavevector along not-rectilinear paths. The effect of the MTS modulation can be analysed in the framework of transformation optics. This article reviews theory and implementation of this MTS transformation and shows some examples at microwave frequencies. PMID:26217056

  3. MC29 deletion mutants which fail to transform chicken macrophages are competent for transformation of quail macrophages.

    PubMed Central

    Biegalke, B J; Heaney, M L; Bouton, A; Parsons, J T; Linial, M

    1987-01-01

    A number of MC29 mutants with deleted myc genes have been previously characterized. Many of these mutants have been found to be defective for transformation of chicken macrophages in vitro and for tumor induction in chickens. Such mutants are capable of transforming Japanese quail macrophages in vitro and inducing a high incidence of tumors in Japanese quail. Thus, Japanese quail may contain a factor(s) capable of complementing the defective transforming proteins encoded by some deleted v-myc genes. Images PMID:3295297

  4. Structural characterization of the pressure-denatured state and unfolding/refolding kinetics of staphylococcal nuclease by synchrotron small-angle X-ray scattering and Fourier-transform infrared spectroscopy.

    PubMed

    Panick, G; Malessa, R; Winter, R; Rapp, G; Frye, K J; Royer, C A

    1998-01-16

    The pressure-induced unfolding of wild-type staphylococcal nuclease (Snase WT) was studied using synchrotron X-ray small-angle scattering (SAXS) and Fourier-transform infrared (FT-IR) spectroscopy, which monitor changes in the tertiary and secondary structural properties of the protein upon pressurization. The experimental results reveal that application of high-pressure up to 3 kbar leads to an approximate twofold increase of the radius of gyration Rg of the native protein (Rg approximately 17 A) and a large broadening of the pair-distance-distribution function, indicating a transition from a globular to an ellipsoidal or extended chain structure. Analysis of the FT-IR amide I' spectral components reveals that the pressure-induced denaturation process sets in at 1.5 kbar at 25 degrees C and is accompanied by an increase in disordered and turn structures while the content of beta-sheets and alpha-helices drastically decreases. The pressure-induced denatured state above 3 kbar retains nonetheless some degree of beta-like secondary structure and the molecule cannot be described as a fully extended random coil. Temperature-induced denaturation involves a further unfolding of the protein molecule which is indicated by a larger Rg value and significantly lower fractional intensities of IR-bands associated with secondary-structure elements. In addition, we have carried out pressure-jump kinetics studies of the secondary-structural evolution and the degree of compactness in the folding/unfolding reactions of Snase. The effect of pressure on the kinetics arises from a larger positive activation volume for folding than for unfolding, and leads to a significant slowing down of the folding rate with increasing pressure. Moreover, the system becomes two-state under pressure. These properties make it ideal for probing multiple order parameters in order to compare the kinetics of changes in secondary structure by pressure-jump FT-IR and chain collapse by pressure-jump SAXS

  5. Hadamard transform imaging

    SciTech Connect

    Morris, M.D.

    1992-01-01

    We have constructed a Hadamard transform Raman microscopic imaging system, and have developed it to a high definition (64K pixel) technique. We have demonstrated multispectral Raman imaging and developed the first three-dimensional (digital confocal) Raman imaging. We have explored the systematic errors in Hadamard multiplexing techniques and developed corrections. We have used our Raman microscope techniques to explore defect distributions on graphite electrodes and damage effects on SERS-activated silver electrodes. We have used the microprobe capabilities of our instrument to investigate the kinetics of polyacrylamide formation in electrolysis capabilities. We have worked closely with a manufacture of holographic displays to develop and incorporate holographic filters and holographic beam splitters into Raman spectrographs and microscopes. Finally, we have developed Hadamard multiplexing techniques for densitometric measurements of protein or nucleic acid blots.

  6. Improving facilities, transforming attitudes.

    PubMed

    Baillie, Jonathan

    2014-04-01

    Providing an effective healing environment for patients facing a wide range of mental health issues, while balancing their needs with security, safety, and affordability considerations, will be key area of focus at this year's Design in Mental Health (DIMH) conference and exhibition, taking place from 13-14 May at the National Motorcycle Museum in Bickenhill near Solihull. As HEJ editor, Jonathan Baillie, reports, conference speakers will include the director of estates and new business at the Priory Group; the chief executive of mental health charity, Mind; architects and designers with substantial mental healthcare experience; top academics, and service-users--all with their own perspective on the 2014 conference theme, 'Improving facilities, transforming attitudes'. PMID:24783329

  7. A piezoelectric transformer

    NASA Technical Reports Server (NTRS)

    Won, C. C.

    1993-01-01

    This work describes a modeling and design method whereby a piezoelectric system is formulated by two sets of second-order equations, one for the mechanical system, and the other for the electrical system, coupled through the piezoelectric effect. The solution to this electromechanical coupled system gives a physical interpretation of the piezoelectric effect as a piezoelectric transformer that is a part of the piezoelectric system, which transfers the applied mechanical force into a force-controlled current source, and short circuit mechanical compliance into capacitance. It also transfers the voltage source into a voltage-controlled relative velocity input, and free motional capacitance into mechanical compliance. The formulation and interpretation simplify the modeling of smart structures and lead to physical insight that aids the designer. Due to its physical realization, the smart structural system can be unconditional stable and effectively control responses. This new concept has been demonstrated in three numerical examples for a simple piezoelectric system.

  8. Imaging Fourier Transform Spectrometer

    SciTech Connect

    Bennett, C.L.; Carter, M.R.; Fields, D.J.; Hernandez, J.

    1993-04-14

    The operating principles of an Imaging Fourier Transform Spectrometer (IFTS) are discussed. The advantages and disadvantages of such instruments with respect to alternative imaging spectrometers are discussed. The primary advantages of the IFTS are the capacity to acquire more than an order of magnitude more spectral channels than alternative systems with more than an order of magnitude greater etendue than for alternative systems. The primary disadvantage of IFTS, or FTS in general, is the sensitivity to temporal fluctuations, either random or periodic. Data from the IRIFTS (ir IFTS) prototype instrument, sensitive in the infrared, are presented having a spectral sensitivity of 0.01 absorbance units, a spectral resolution of 6 cm{sup {minus}1} over the range 0 to 7899 cm{sup {minus}1}, and a spatial resolution of 2.5 mr.

  9. Anaerobic transformation of TNT

    SciTech Connect

    Kulpa, C.F.; Roopathy, R.

    1995-12-31

    Most studies on the microbial metabolism of nitroaromatic compounds have used aerobic tempts to degrade nitroaromatics under aerobic microorganisms. In many cases attempts to degrade nitroaromatics under aerobic conditions results in no mineralization and only superficial modifications of the structure. However, under anaerobic sulfate-reducing conditions, the nitroaromatic compounds undergo a series of reductions with the formation of amino compounds. Trinitrotoluene under sulfate-reducing conditions is reduced to triaminotoluene presumably by the enzyme nitrite reductase, which is commonly found in many Desulfovibrio spp. The removal of nitrate from trinitrotoluene is achieved by a series of reductive reactions with the production of ammonia and toluene by Desulfovibrio sp. (B strain). Similar metabolic processes could be applied to other nitroaromatic compounds like nitrobenzene, nitrobenzoic acids, nitrophenols, and aniline. This presentation will review the data supporting the anaerobic transformation of TNT and other nitroaromatics.

  10. Semiosis and Energy Transformation

    NASA Astrophysics Data System (ADS)

    Taborsky, Edwina

    2002-09-01

    Semiosis is understood as a process of transforming energy to mass via measurement. Measurement is an action of codification, organizing energy within different modes of relation. Measurement is examined within a series of ontological and epistemological cuts that increase asymmetry by first differentiating energy/mass into external and internal realms and then differentiating these realms into formal mind-models and informal mass-instances. These realms are examined within the three Peircean modes of Firstness. Secondness and Thirdness to explore five different processes of codification that encode energy to mass within a maturing complexity. Codification within these five processes is examined within classical and quantum mechanics and concludes that we require both mechanics of codification to provide a generative semiosis.

  11. Fourier Transform Spectrometer System

    NASA Technical Reports Server (NTRS)

    Campbell, Joel F. (Inventor)

    2014-01-01

    A Fourier transform spectrometer (FTS) data acquisition system includes an FTS spectrometer that receives a spectral signal and a laser signal. The system further includes a wideband detector, which is in communication with the FTS spectrometer and receives the spectral signal and laser signal from the FTS spectrometer. The wideband detector produces a composite signal comprising the laser signal and the spectral signal. The system further comprises a converter in communication with the wideband detector to receive and digitize the composite signal. The system further includes a signal processing unit that receives the composite signal from the converter. The signal processing unit further filters the laser signal and the spectral signal from the composite signal and demodulates the laser signal, to produce velocity corrected spectral data.

  12. A dynamic phase-field model for structural transformations and twinning: Regularized interfaces with transparent prescription of complex kinetics and nucleation. Part II: Two-dimensional characterization and boundary kinetics

    NASA Astrophysics Data System (ADS)

    Agrawal, Vaibhav; Dayal, Kaushik

    2015-12-01

    A companion paper presented the formulation of a phase-field model - i.e., a model with regularized interfaces that do not require explicit numerical tracking - that allows for easy and transparent prescription of complex interface kinetics and nucleation. The key ingredients were a re-parametrization of the energy density to clearly separate nucleation from kinetics; and an evolution law that comes from a conservation statement for interfaces. This enables clear prescription of nucleation through the source term of the conservation law and of kinetics through an interfacial velocity field. This model overcomes an important shortcoming of existing phase-field models, namely that the specification of kinetics and nucleation is both restrictive and extremely opaque. In this paper, we present a number of numerical calculations - in one and two dimensions - that characterize our formulation. These calculations illustrate (i) highly-sensitive rate-dependent nucleation; (ii) independent prescription of the forward and backward nucleation stresses without changing the energy landscape; (iii) stick-slip interface kinetics; (iii) the competition between nucleation and kinetics in determining the final microstructural state; (iv) the effect of anisotropic kinetics; and (v) the effect of non-monotone kinetics. These calculations demonstrate the ability of this formulation to precisely prescribe complex nucleation and kinetics in a simple and transparent manner. We also extend our conservation statement to describe the kinetics of the junction lines between microstructural interfaces and boundaries. This enables us to prescribe an additional kinetic relation for the boundary, and we examine the interplay between the bulk kinetics and the junction kinetics.

  13. Mechanical properties of fibroblasts depend on level of cancer transformation.

    PubMed

    Efremov, Yu M; Lomakina, M E; Bagrov, D V; Makhnovskiy, P I; Alexandrova, A Y; Kirpichnikov, M P; Shaitan, K V

    2014-05-01

    Recently, it was revealed that tumor cells are significantly softer than normal cells. Although this phenomenon is well known, it is connected with many questions which are still unanswered. Among these questions are the molecular mechanisms which cause the change in stiffness and the correlation between cell mechanical properties and their metastatic potential. We studied mechanical properties of cells with different levels of cancer transformation. Transformed cells in three systems with different transformation types (monooncogenic N-RAS, viral and cells of tumor origin) were characterized according to their morphology, actin cytoskeleton and focal adhesion organization. Transformation led to reduction of cell spreading and thus decreasing the cell area, disorganization of actin cytoskeleton, lack of actin stress fibers and decline in the number and size of focal adhesions. These alterations manifested in a varying degree depending on type of transformation. Force spectroscopy by atomic force microscopy with spherical probes was carried out to measure the Young's modulus of cells. In all cases the Young's moduli were fitted well by log-normal distribution. All the transformed cell lines were found to be 40-80% softer than the corresponding normal ones. For the cell system with a low level of transformation the difference in stiffness was less pronounced than for the two other systems. This suggests that cell mechanical properties change upon transformation, and acquisition of invasive capabilities is accompanied by significant softening. PMID:24530505

  14. Transformation of Morinda citrifolia via simple mature seed imbibition method.

    PubMed

    Lee, J J; Ahmad, S; Roslan, H A

    2013-12-15

    Morinda citrifolia, is a valuable medicinal plant with a wide range of therapeutic properties and extensive transformation study on this plant has yet been known. Present study was conducted to establish a simple and reliable transformation protocol for M. citrifolia utilising Agrobacterium tumefaciens via direct seed exposure. In this study, the seeds were processed by tips clipping and dried and subsequently incubated in inoculation medium. Four different parameters during the incubation such as incubation period, bacterial density, temperature and binary vectors harbouring beta-glucuronidase (GUS) gene (pBI121 and pGSA1131), were tested to examine its effect on transformation efficiency. The leaves from the treated and germinated seedlings were analysed via Polymerase Chain Reaction (PCR), histochemical assay of the GUS gene and reverse transcription-PCR (RT-PCR). Results of the study showed that Agrobacterium strain LBA4404 with optical density of 1.0 and 2 h incubation period were optimum for M. citrifolia transformation. It was found that various co-cultivation temperatures tested and type of vector used did not affect the transformation efficiency. The highest transformation efficiency for M. citrifolia direct seed transformation harbouring pBI121 and pGSA1131 was determined to be 96.8% with 2 h co-cultivation treatment and 80.4% when using bacterial density of 1.0, respectively. The transformation method can be applied for future characterization study of M. citrifolia. PMID:24517006

  15. Efficient polarimetric BRDF transformations

    NASA Astrophysics Data System (ADS)

    Björkert, Stefan; Renhorn, Ingmar G. E.

    2016-05-01

    In order to characterize a target, the basic information that is of interest is spectral, polarization and distance. Imaging spectropolarimetry is a powerful tool for obtaining the polarization state of a scene and to discriminate manmade objects in a cluttered background. With respect to polarization, often the measurements are limited to the first three components of the Stokes vector, excluding circular polarization. The scene is therefore characterized in four directions of linear polarization, I0, I90, I45 and I135. An efficient polarimetric BRDF model defined in a local coordinate system has recently been published. The model will now be extended to a global coordinate system for linear polarized radiation. This includes the first three elements of the Stokes vector. We will provide examples for surface of intrinsically different scattering materials, bulk scattering materials and clear coated surfaces.

  16. Transformation plasticity in ductile solids

    SciTech Connect

    Olson, G.B.

    1993-02-01

    Research has addressed the role of martensitic transformation plasticity in the enhancement of toughness in high-strength austenitic steels, and the enhancement of formability in multiphase low-alloy sheet steels. In the austenitic steels, optimal processing conditions have been established to achieve a significant increase in strength level, in order to investigate the interaction of strain-induced transformation with the microvoid nucleation and shear localization mechanisms operating at ultrahigh strength levels. The stress-state dependence of transformation and fracture mechanisms has been investigated in model alloys, comparing behavior in uniaxial tension and blunt-notch tension specimens. A numerical constitutive model for transformation plasticity has been reformulated to allow a more thorough analysis of transformation/fracture interactions. Processing of a new low alloy steel composition has been optimized to stabilize retained austenite by isothermal bainitic transformation after intercritical annealing. Preliminary results show a good correlation of uniform ductility with the austenite amount and stability.

  17. Reflectional transformation for structural stiffness

    SciTech Connect

    Vashi, K.M.

    1990-01-01

    This paper presents a structural reflection-related transformation for structural stiffness. The stiffness transformation addresses reflection of a structure about any of the three coordinate planes and renders the desired stiffness matrix using a stiffness matrix for the same structure before reflection. This transformation is elegant and simple, provides an efficient and technically rigorous approach to derive the required stiffness matrix without structural remodeling, and can be readily programmed to quickly perform the required matrix manipulations. 2 figs.

  18. Transformation Systems at NASA Ames

    NASA Technical Reports Server (NTRS)

    Buntine, Wray; Fischer, Bernd; Havelund, Klaus; Lowry, Michael; Pressburger, TOm; Roach, Steve; Robinson, Peter; VanBaalen, Jeffrey

    1999-01-01

    In this paper, we describe the experiences of the Automated Software Engineering Group at the NASA Ames Research Center in the development and application of three different transformation systems. The systems span the entire technology range, from deductive synthesis, to logic-based transformation, to almost compiler-like source-to-source transformation. These systems also span a range of NASA applications, including solving solar system geometry problems, generating data analysis software, and analyzing multi-threaded Java code.

  19. Cereal transformation through particle bombardment

    NASA Technical Reports Server (NTRS)

    Casas, A. M.; Kononowicz, A. K.; Bressan, R. A.; Hasegawa, P. M.; Mitchell, C. A. (Principal Investigator)

    1995-01-01

    The review focuses on experiments that lead to stable transformation in cereals using microprojectile bombardment. The discussion of biological factors that affect transformation examines target tissues and vector systems for gene transfer. The vector systems include reporter genes, selectable markers, genes of agronomic interest, and vector constructions. Other topics include physical parameters that affect DNA delivery, selection of stably transformed cells and plant regeneration, and analysis of gene expression and transmission to the progeny.

  20. The ABB transformer monitoring system

    SciTech Connect

    Claiborne, C.; Gorman, M.; Petrie, E.M.

    1996-03-01

    ABB is currently developing a transformer monitoring system that will continuously perform multiple gas-in-oil and partial discharge analyses. The new monitoring system is designed to be simple and reliable. It can be applied to new units or easily retrofitted to existing transformers. The parameters that are monitored are those that are most commonly evaluated when diagnosing the condition of a power transformer. A multiple gas monitor can selectively detect and measure hydrogen, carbon monoxide, and the combination of methane and ethane. The partial discharge monitor employs an electrical method to detect partial discharges that originate from sources only within the transformer. Prototype systems will be field tested in 1995.