WorldWideScience

Sample records for global spectral study

  1. Global Source Parameters from Regional Spectral Ratios for Yield Transportability Studies

    Science.gov (United States)

    Phillips, W. S.; Fisk, M. D.; Stead, R. J.; Begnaud, M. L.; Rowe, C. A.

    2016-12-01

    We use source parameters such as moment, corner frequency and high frequency rolloff as constraints in amplitude tomography, ensuring that spectra of well-studied earthquakes are recovered using the ensuing attenuation and site term model. We correct explosion data for path and site effects using such models, which allows us to test transportability of yield estimation techniques based on our best source spectral estimates. To develop a background set of source parameters, we applied spectral ratio techniques to envelopes of a global set of regional distance recordings from over 180,000 crustal events. Corner frequencies and moment ratios were determined via inversion using all event pairs within predetermined clusters, shifting to absolute levels using independently determined regional and teleseismic moments. The moment and corner frequency results can be expressed as stress drop, which has considerable scatter, yet shows dramatic regional patterns. We observe high stress in subduction zones along S. America, S. Mexico, the Banda Sea, and associated with the Yakutat Block in Alaska. We also observe high stress at the Himalayan syntaxes, the Pamirs, eastern Iran, the Caspian, the Altai-Sayan, and the central African rift. Low stress is observed along mid ocean spreading centers, the Afar rift, patches of convergence zones such as Nicaragua, the Zagros, Tibet, and the Tien Shan, among others. Mine blasts appear as low stress events due to their low corners and steep rolloffs. Many of these anomalies have been noted by previous studies, and we plan to compare results directly. As mentioned, these results will be used to constrain tomographic imaging, but can also be used in model validation procedures similar to the use of ground truth in location problems, and, perhaps most importantly, figure heavily in quality control of local and regional distance amplitude measurements.

  2. A Global Spectral Study of Stellar-Mass Black Holes with Unprecedented Sensitivity

    Science.gov (United States)

    Garci, Javier

    There are two well established populations of black holes: (i) stellar-mass black holes with masses in the range 5 to 30 solar masses, many millions of which are present in each galaxy in the universe, and (ii) supermassive black holes with masses in the range millions to billions of solar masses, which reside in the nucleus of most galaxies. Supermassive black holes play a leading role in shaping galaxies and are central to cosmology. However, they are hard to study because they are dim and they scarcely vary on a human timescale. Luckily, their variability and full range of behavior can be very effectively studied by observing their stellar-mass cousins, which display in miniature the full repertoire of a black hole over the course of a single year. The archive of data collected by NASA's Rossi X-ray Timing Explorer (RXTE) during its 16 year mission is of first importance for the study of stellar-mass black holes. While our ultimate goal is a complete spectral analysis of all the stellar-mass black hole data in the RXTE archive, the goal of this proposal is the global study of six of these black holes. The two key methodologies we bring to the study are: (1) Our recently developed calibration tool that increases the sensitivity of RXTE's detector by up to an order of magnitude; and (2) the leading X-ray spectral "reflection" models that are arguably the most effective means currently available for probing the effects of strong gravity near the event horizon of a black hole. For each of the six black holes, we will fit our models to all the archived spectral data and determine several key parameters describing the black hole and the 10-million-degree gas that surrounds it. Of special interest will be our measurement of the spin (or rate of rotation) of each black hole, which can be as high as tens of thousands of RPM. Profoundly, all the properties of an astronomical black hole are completely defined by specifying its spin and its mass. The main goal of this

  3. On the spectral composition of global radiation

    Energy Technology Data Exchange (ETDEWEB)

    Major, G

    1983-01-01

    The global radiation is recorded at several stations on the Earth. The information about its spectral composition is poor. In this paper the spectral composition means the ratio of spectral global radiation measured by coloured glass filter domes to the total global radiation. From the measuements made by Klein and Goldberg it follows that the monthly ratios vary significantly from place to place, while the variations from month to month at one place are significant only at the station which lies near to the North Pole. The Budapest data proved the dominant effect of cloudiness on the spectral composition of global radiation. This effect is in good statistical relationship with the relative global radiation. The regression constant tabulated in this paper do not contain the error of zero point elevation which is due to the overheating of glass filters by the absorbed solar radiation.

  4. On global and regional spectral evaluation of global geopotential models

    International Nuclear Information System (INIS)

    Ustun, A; Abbak, R A

    2010-01-01

    Spectral evaluation of global geopotential models (GGMs) is necessary to recognize the behaviour of gravity signal and its error recorded in spherical harmonic coefficients and associated standard deviations. Results put forward in this wise explain the whole contribution of gravity data in different kinds that represent various sections of the gravity spectrum. This method is more informative than accuracy assessment methods, which use external data such as GPS-levelling. Comparative spectral evaluation for more than one model can be performed both in global and local sense using many spectral tools. The number of GGMs has grown with the increasing number of data collected by the dedicated satellite gravity missions, CHAMP, GRACE and GOCE. This fact makes it necessary to measure the differences between models and to monitor the improvements in the gravity field recovery. In this paper, some of the satellite-only and combined models are examined in different scales, globally and regionally, in order to observe the advances in the modelling of GGMs and their strengths at various expansion degrees for geodetic and geophysical applications. The validation of the published errors of model coefficients is a part of this evaluation. All spectral tools explicitly reveal the superiority of the GRACE-based models when compared against the models that comprise the conventional satellite tracking data. The disagreement between models is large in local/regional areas if data sets are different, as seen from the example of the Turkish territory

  5. Electromagnetic microinstabilities in tokamak plasmas using a global spectral approach

    Energy Technology Data Exchange (ETDEWEB)

    Falchetto, G. L

    2002-03-01

    Electromagnetic microinstabilities in tokamak plasmas are studied by means of a linear global eigenvalue numerical code. The code is the electromagnetic extension of an existing electrostatic global gyrokinetic spectral toroidal code, called GLOGYSTO. Ion dynamics is described by the gyrokinetic equation, so that ion finite Larmor radius effects are taken into account to all orders. Non adiabatic electrons are included in the model, with passing particles described by the drift-kinetic equation and trapped particles through the bounce averaged drift-kinetic equation. A low frequency electromagnetic perturbation is applied to a low -but finite- {beta}plasma (where the parameter {beta} identifies the ratio of plasma pressure to magnetic pressure); thus, the parallel perturbations of the magnetic field are neglected. The system is closed by the quasi-neutrality equation and the parallel component of Ampere's law. The formulation is applied to a large aspect ratio toroidal configuration, with circular shifted surfaces. Such a simple configuration enables one to derive analytically the gyrocenter trajectories. The system is solved in Fourier space, taking advantage of a decomposition adapted to the toroidal geometry. The major contributions of this thesis are as follows. The electromagnetic effects on toroidal Ion Temperature Gradient driven (ITG) modes are studied. The stabilization of these modes with increasing {beta}, as predicted in previous work, is confirmed. The inclusion of trapped electron dynamics enables the study of its coupling to the ITG modes and of Trapped Electron Modes (TEM) .The effects of finite {beta} are considered together with those of different magnetic shear profiles and of the Shafranov shift. The threshold for the destabilization of an electromagnetic mode is identified. Moreover, the global formulation yields for the first time the radial structure of this so-called Alfvenic Ion Temperature Gradient (AITG) mode. The stability of the

  6. Evaluation of the desert dust effects on global, direct and diffuse spectral ultraviolet irradiance

    Directory of Open Access Journals (Sweden)

    R. Román

    2013-01-01

    Full Text Available This paper presents a study of a strong desert dust episode over the Iberian Peninsula, and its effect on the spectral ultraviolet (UV irradiance in Granada, Spain. Remote sensing measurements, forecast models, and synoptic analysis are used to identify a Saharan desert dust outbreak that affected the Iberian Peninsula starting 20 July 2009. Additionally, a Bentham DMc150 spectroradiometer is employed to obtain global, direct and diffuse spectral UV irradiances every 15 minutes in Granada. The desert dust caused a large attenuation of the direct UV irradiance (up to 55%, while the diffuse UV irradiance increased up to 40% at 400 nm. The UVSPEC/LibRadtran radiative transfer model is used to study the spectral dependence of the experimental UV irradiance ratios (ratios of spectral irradiance for the day with the highest aerosol load to that measured in days with low–moderate load. The spectral increase or decrease of the UV direct irradiance ratios depends on a new parameter: a threshold wavelength. The spectral dependence of the UV diffuse irradiance ratio can be explained because under the influence of the intense dust outbreak, the Mie scattering by aerosols at shorter wavelengths is stronger than the Rayleigh scattering by gases. Finally, the sensitivity analysis of the aerosol absorption properties shows a substantial attenuation of UV spectral irradiance with a weak spectral dependence.

  7. A global spectral library to characterize the world's soil

    DEFF Research Database (Denmark)

    A. Viscarra Rossel, Raphael; Behrens, T.; Ben Dor, E.

    2016-01-01

    to sustainably manage and preserve it for future generations. To this end, we developed and analyzed a global soil visible–near infrared (vis–NIR) spectral library. It is currently the largest and most diverse database of its kind. We show that the information encoded in the spectra can describe soil composition...... help to deal with the shortage of data on soil to better understand it and to meet the growing demand for information to assess andmonitor soil at scales ranging fromregional to global.New contributions to the library are encouraged so that this work and our collaboration might progress to develop......Soil provides ecosystemservices, supports human health and habitation, stores carbon and regulatesemissions of greenhouse gases. Unprecedented pressures on soil from degradation and urbanization are threatening agroecological balances and food security. It is important that we learn more about soil...

  8. Local and Global Gestalt Laws: A Neurally Based Spectral Approach.

    Science.gov (United States)

    Favali, Marta; Citti, Giovanna; Sarti, Alessandro

    2017-02-01

    This letter presents a mathematical model of figure-ground articulation that takes into account both local and global gestalt laws and is compatible with the functional architecture of the primary visual cortex (V1). The local gestalt law of good continuation is described by means of suitable connectivity kernels that are derived from Lie group theory and quantitatively compared with long-range connectivity in V1. Global gestalt constraints are then introduced in terms of spectral analysis of a connectivity matrix derived from these kernels. This analysis performs grouping of local features and individuates perceptual units with the highest salience. Numerical simulations are performed, and results are obtained by applying the technique to a number of stimuli.

  9. Global Learning Spectral Archive- A new Way to deal with Unknown Urban Spectra -

    Science.gov (United States)

    Jilge, M.; Heiden, U.; Habermeyer, M.; Jürgens, C.

    2015-12-01

    Rapid urbanization processes and the need of identifying urban materials demand urban planners and the remote sensing community since years. Urban planners cannot overcome the issue of up-to-date information of urban materials due to time-intensive fieldwork. Hyperspectral remote sensing can facilitate this issue by interpreting spectral signals to provide information of occurring materials. However, the complexity of urban areas and the occurrence of diverse urban materials vary due to regional and cultural aspects as well as the size of a city, which makes identification of surface materials a challenging analysis task. For the various surface material identification approaches, spectral libraries containing pure material spectra are commonly used, which are derived from field, laboratory or the hyperspectral image itself. One of the requirements for successful image analysis is that all spectrally different surface materials are represented by the library. Currently, a universal library, applicable in every urban area worldwide and taking each spectral variability into account, is and will not be existent. In this study, the issue of unknown surface material spectra and the demand of an urban site-specific spectral library is tackled by the development of a learning spectral archive tool. Starting with an incomplete library of labelled image spectra from several German cities, surface materials of pure image pixels will be identified in a hyperspectral image based on a similarity measure (e.g. SID-SAM). Additionally, unknown image spectra of urban objects are identified based on an object- and spectral-based-rule set. The detected unknown surface material spectra are entered with additional metadata, such as regional occurrence into the existing spectral library and thus, are reusable for further studies. Our approach is suitable for pure surface material detection of urban hyperspectral images that is globally applicable by taking incompleteness into account

  10. Finite size scaling and spectral density studies

    International Nuclear Information System (INIS)

    Berg, B.A.

    1991-01-01

    Finite size scaling (FSS) and spectral density (SD) studies are reported for the deconfining phase transition. This talk concentrates on Monte Carlo (MC) results for pure SU(3) gauge theory, obtained in collaboration with Alves and Sanielevici, but the methods are expected to be useful for full QCD as well. (orig.)

  11. Global analysis of the persistence of the spectral signal associated with burned areas

    Science.gov (United States)

    Melchiorre, A.; Boschetti, L.

    2015-12-01

    Systematic global burned area maps at coarse spatial resolution (350 m - 1 km) have been produced in the past two decades from several Earth Observation (EO) systems (including MODIS, Spot-VGT, AVHRR, MERIS), and have been extensively used in a variety of applications related to emissions estimation, fire ecology, and vegetation monitoring (Mouillot et al. 2014). There is however a strong need for moderate to high resolution (10-30 m) global burned area maps, in order to improve emission estimations, in particular on heterogeneous landscapes and for local scale air quality applications, for fire management and environmental restoration, and in support of carbon accounting (Hyer and Reid 2009; Mouillot et al. 2014; Randerson et al. 2012). Fires causes a non-permanent land cover change: the ash and charcoal left by the fire can be visible for a period ranging from a few weeks in savannas and grasslands ecosystems, to over a year in forest ecosystems (Roy et al. 2010). This poses a major challenge for designing a global burned area mapping system from moderate resolution (10-30 m) EO data, due to the low revisit time frequency of the satellites (Boschetti et al. 2015). As a consequence, a quantitative assessment of the permanence of the spectral signature of burned areas at global scale is a necessary step to assess the feasibility of global burned area mapping with moderate resolution sensors. This study presents a global analysis of the post-fire reflectance of burned areas, using the MODIS MCD45A1 global burned area product to identify the location and timing of burning, and the MO(Y)D09 global surface reflectance product to retrieve the time series of reflectance values after the fire. The result is a spatially explicit map of persistence of burned area signal, which is then summarized by landcover type, and by fire zone using the subcontinental regions defined by Giglio et al. (2006).

  12. Studies of global warming and global energy

    International Nuclear Information System (INIS)

    Inaba, Atsushi

    1993-01-01

    Global warming caused by increase in atmospheric CO 2 concentration has been the focus of many recent global energy studies. CO 2 is emitted to the atmosphere mainly from the combustion of fossil fuels. This means that global warming is fundamentally a problem of the global energy system. An analysis of the findings of recent global energy studies is made in this report. The results are categorized from the viewpoint of concern about global warming. The analysis includes energy use and CO 2 emissions, measures taken to restrain CO 2 emissions and the cost of such measure, and suggestions for long term global energy generation. Following this comparative analysis, each of the studies is reviewed in detail. (author) 63 refs

  13. Global spectral graph wavelet signature for surface analysis of carpal bones

    Science.gov (United States)

    Masoumi, Majid; Rezaei, Mahsa; Ben Hamza, A.

    2018-02-01

    Quantitative shape comparison is a fundamental problem in computer vision, geometry processing and medical imaging. In this paper, we present a spectral graph wavelet approach for shape analysis of carpal bones of the human wrist. We employ spectral graph wavelets to represent the cortical surface of a carpal bone via the spectral geometric analysis of the Laplace-Beltrami operator in the discrete domain. We propose global spectral graph wavelet (GSGW) descriptor that is isometric invariant, efficient to compute, and combines the advantages of both low-pass and band-pass filters. We perform experiments on shapes of the carpal bones of ten women and ten men from a publicly-available database of wrist bones. Using one-way multivariate analysis of variance (MANOVA) and permutation testing, we show through extensive experiments that the proposed GSGW framework gives a much better performance compared to the global point signature embedding approach for comparing shapes of the carpal bones across populations.

  14. Analysis of global water vapour trends from satellite measurements in the visible spectral range

    Directory of Open Access Journals (Sweden)

    S. Mieruch

    2008-02-01

    Full Text Available Global water vapour total column amounts have been retrieved from spectral data provided by the Global Ozone Monitoring Experiment (GOME flying on ERS-2, which was launched in April 1995, and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY onboard ENVISAT launched in March 2002. For this purpose the Air Mass Corrected Differential Optical Absorption Spectroscopy (AMC-DOAS approach has been used. The combination of the data from both instruments provides us with a long-term global data set spanning more than 11 years with the potential of extension up to 2020 by GOME-2 data on MetOp.

    Using linear and non-linear methods from time series analysis and standard statistics the trends of H2O columns and their errors have been calculated. In this study, factors affecting the trend such as the length of the time series, the magnitude of the variability of the noise, and the autocorrelation of the noise are investigated. Special emphasis has been placed on the calculation of the statistical significance of the observed trends, which reveal significant local changes from −5% per year to +5% per year. These significant trends are distributed over the whole globe. Increasing trends have been calculated for Greenland, East Europe, Siberia and Oceania, whereas decreasing trends have been observed for the northwest USA, Central America, Amazonia, Central Africa and the Arabian Peninsular.

  15. Directional and Spectral Irradiance in Ocean Models: Effects on Simulated Global Phytoplankton, Nutrients, and Primary Production

    Science.gov (United States)

    Gregg, Watson W.; Rousseaux, Cecile S.

    2016-01-01

    The importance of including directional and spectral light in simulations of ocean radiative transfer was investigated using a coupled biogeochemical-circulation-radiative model of the global oceans. The effort focused on phytoplankton abundances, nutrient concentrations and vertically-integrated net primary production. The importance was approached by sequentially removing directional (i.e., direct vs. diffuse) and spectral irradiance and comparing results of the above variables to a fully directionally and spectrally-resolved model. In each case the total irradiance was kept constant; it was only the pathways and spectral nature that were changed. Assuming all irradiance was diffuse had negligible effect on global ocean primary production. Global nitrate and total chlorophyll concentrations declined by about 20% each. The largest changes occurred in the tropics and sub-tropics rather than the high latitudes, where most of the irradiance is already diffuse. Disregarding spectral irradiance had effects that depended upon the choice of attenuation wavelength. The wavelength closest to the spectrally-resolved model, 500 nm, produced lower nitrate (19%) and chlorophyll (8%) and higher primary production (2%) than the spectral model. Phytoplankton relative abundances were very sensitive to the choice of non-spectral wavelength transmittance. The combined effects of neglecting both directional and spectral irradiance exacerbated the differences, despite using attenuation at 500 nm. Global nitrate decreased 33% and chlorophyll decreased 24%. Changes in phytoplankton community structure were considerable, representing a change from chlorophytes to cyanobacteria and coccolithophores. This suggested a shift in community function, from light-limitation to nutrient limitation: lower demands for nutrients from cyanobacteria and coccolithophores favored them over the more nutrient-demanding chlorophytes. Although diatoms have the highest nutrient demands in the model, their

  16. Calculating spectral direct solar irradiance, diffuse and global in Heredia, Costa Rica

    International Nuclear Information System (INIS)

    Wright, Jaime

    2008-01-01

    A spectral model under conditions of clear skies has described the flow of solar irradiation and is verified experimentally in Heredia, Costa Rica. A description of the model is presented by comparing its results with experimental measurements. The model has calculated the spectral flows of the global solar irradiation, direct and diffuse incident on a horizontal surface. Necessary input data include latitude, altitude, surface albedo as characteristics of a locality, and atmospheric characteristics: turbidity, precipitable water vapor, total ozone content and the optical thickness of a particular subject. The results show satisfactory values. (author) [es

  17. Global Convergence of a Spectral Conjugate Gradient Method for Unconstrained Optimization

    Directory of Open Access Journals (Sweden)

    Jinkui Liu

    2012-01-01

    Full Text Available A new nonlinear spectral conjugate descent method for solving unconstrained optimization problems is proposed on the basis of the CD method and the spectral conjugate gradient method. For any line search, the new method satisfies the sufficient descent condition gkTdk<−∥gk∥2. Moreover, we prove that the new method is globally convergent under the strong Wolfe line search. The numerical results show that the new method is more effective for the given test problems from the CUTE test problem library (Bongartz et al., 1995 in contrast to the famous CD method, FR method, and PRP method.

  18. Power spectral density and scaling exponent of high frequency global solar radiation sequences

    Science.gov (United States)

    Calif, Rudy; Schmitt, François G.; Huang, Yongxiang

    2013-04-01

    The part of the solar power production from photovlotaïcs systems is constantly increasing in the electric grids. Solar energy converter devices such as photovoltaic cells are very sensitive to instantaneous solar radiation fluctuations. Thus rapid variation of solar radiation due to changes in the local meteorological condition can induce large amplitude fluctuations of the produced electrical power and reduce the overall efficiency of the system. When large amount of photovoltaic electricity is send into a weak or small electricity network such as island network, the electric grid security can be in jeopardy due to these power fluctuations. The integration of this energy in the electrical network remains a major challenge, due to the high variability of solar radiation in time and space. To palliate these difficulties, it is essential to identify the characteristic of these fluctuations in order to anticipate the eventuality of power shortage or power surge. The objective of this study is to present an approach based on Empirical Mode Decomposition (EMD) and Hilbert-Huang Transform (HHT) to highlight the scaling properties of global solar irradiance data G(t). The scale of invariance is detected on this dataset using the Empirical Mode Decomposition in association with arbitrary-order Hilbert spectral analysis, a generalization of (HHT) or Hilbert Spectral Analysis (HSA). The first step is the EMD, consists in decomposing the normalized global solar radiation data G'(t) into several Intrinsic Mode Functions (IMF) Ci(t) without giving an a priori basis. Consequently, the normalized original solar radiation sequence G'(t) can be written as a sum of Ci(t) with a residual rn. From all IMF modes, a joint PDF P(f,A) of locally and instantaneous frequency f and amplitude A, is estimated. To characterize the scaling behavior in amplitude-frequency space, an arbitrary-order Hilbert marginal spectrum is defined to: Iq(f) = 0 P (f,A)A dA (1) with q × 0 In case of scale

  19. [Study on the arc spectral information for welding quality diagnosis].

    Science.gov (United States)

    Li, Zhi-Yong; Gu, Xiao-Yan; Li, Huan; Yang, Li-Jun

    2009-03-01

    Through collecting the spectral signals of TIG and MIG welding arc with spectrometer, the arc light radiations were analyzed based on the basic theory of plasma physics. The radiation of welding arc distributes over a broad range of frequency, from infrared to ultraviolet. The arc spectrum is composed of line spectra and continuous spectra. Due to the variation of metal density in the welding arc, there is great difference between the welding arc spectra of TIG and MIG in both their intensity and distribution. The MIG welding arc provides more line spectra of metal and the intensity of radiation is greater than TIG. The arc spectrum of TIG welding is stable during the welding process, disturbance factors that cause the spectral variations can be reflected by the spectral line related to the corresponding element entering the welding arc. The arc spectrum of MIG welding will fluctuate severely due to droplet transfer, which produces "noise" in the line spectrum aggregation zone. So for MIG welding, the spectral zone lacking spectral line is suitable for welding quality diagnosis. According to the characteristic of TIG and MIG, special spectral zones were selected for welding quality diagnosis. For TIG welding, the selected zone is in ultraviolet zone (230-300 nm). For MIG welding, the selected zone is in visible zone (570-590 nm). With the basic theory provided for welding quality diagnosis, the integral intensity of spectral signal in the selected zone of welding process with disturbing factor was studied to prove the theory. The results show that the welding quality and disturbance factors can be diagnosed with good signal to noise ratio in the selected spectral zone compared with signal in other spectral zone. The spectral signal can be used for real-time diagnosis of the welding quality.

  20. Variational study of spectral shifts. II

    International Nuclear Information System (INIS)

    Peton, A.

    1979-01-01

    In a static gravitational field the paths of light are curved. This property can be a priori stated for a V 3 Riemannian manifold: through any two points of V 3 it is possible to draw two families of curves, the straight lines of Euclidean geometry and the photon trajectories z. A fibration of the Galilean space-time can be performed in an original way, by taking the z-trajectories of the photons as the base, the isochronic surfaces as fibres, and 'the equal length time on a z trajectory to reach a given point' as the equivalence relation. The straight lines of Euclidean geometry can then carry the classical mechanics time t, and the z trajectories can carry the optics time (T). These times are related by d(T)=F(x,t)dt. If the Universe is classed as a pseudo-Riemannian manifold of normal hyperbolic type Csup(infinity), the time (T) determined above can be taken as the time coordinate in V 4 . Under these conditions d(S) 2 =F 2 ds 2 , where d(S) 2 is the metric of the Riemannian manifold, conforming to the metric ds 2 and allowing (T) as the cosmic time. The results previously achieved by the author (Peton, 1979) can be used to find 1+zsub(G)=F(Asub(s), tsub(s))/F(Asub(O),tsub(O)) where zsub(G) denotes the shift of the spectral lines due to the metric. In the case of relative motion between O and S, 1+z'=(1+zsub(G))(1+βsub(r))(1-β 2 )sup(-1/2)). The Doppler-Fizeau effect therefore appears as a result of the application of the Fermat principle. (Auth.)

  1. Nightside studies of coherent HF Radar spectral width behaviour

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    2002-09-01

    Full Text Available A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1 exists poleward of a region of low HF spectral width (<200 ms-1. Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1 have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to the data presented here. Since the

  2. Nightside studies of coherent HF Radar spectral width behaviour

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    Full Text Available A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1 exists poleward of a region of low HF spectral width (<200 ms-1. Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1 have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to

  3. Using GIS servers and interactive maps in spectral data sharing and administration: Case study of Ahvaz Spectral Geodatabase Platform (ASGP)

    Science.gov (United States)

    Karami, Mojtaba; Rangzan, Kazem; Saberi, Azim

    2013-10-01

    With emergence of air-borne and space-borne hyperspectral sensors, spectroscopic measurements are gaining more importance in remote sensing. Therefore, the number of available spectral reference data is constantly increasing. This rapid increase often exhibits a poor data management, which leads to ultimate isolation of data on disk storages. Spectral data without precise description of the target, methods, environment, and sampling geometry cannot be used by other researchers. Moreover, existing spectral data (in case it accompanied with good documentation) become virtually invisible or unreachable for researchers. Providing documentation and a data-sharing framework for spectral data, in which researchers are able to search for or share spectral data and documentation, would definitely improve the data lifetime. Relational Database Management Systems (RDBMS) are main candidates for spectral data management and their efficiency is proven by many studies and applications to date. In this study, a new approach to spectral data administration is presented based on spatial identity of spectral samples. This method benefits from scalability and performance of RDBMS for storage of spectral data, but uses GIS servers to provide users with interactive maps as an interface to the system. The spectral files, photographs and descriptive data are considered as belongings of a geospatial object. A spectral processing unit is responsible for evaluation of metadata quality and performing routine spectral processing tasks for newly-added data. As a result, by using internet browser software the users would be able to visually examine availability of data and/or search for data based on descriptive attributes associated to it. The proposed system is scalable and besides giving the users good sense of what data are available in the database, it facilitates participation of spectral reference data in producing geoinformation.

  4. Mapping a Part of Neuquén Basin in Argentina by Global-phase H/V Spectral Ratio

    NARCIS (Netherlands)

    Nishitsuji, Yohei; Ruigrok, E.N.; Gomez, M.; Draganov, Deyan

    2015-01-01

    We investigated the applicability of global phases (epicentral distances of ≥ 120° and ≥ 150°) for the H/V spectral ratio to identify the fundamental resonance frequency. We applied the method to delineate a part of Neuquén basin in Argentina without the need for active seismic sources. We obtained

  5. Mapping a part of Neuquen Basin in Argentina by global-phase H/V spectral ratio

    NARCIS (Netherlands)

    Nishitsuji, Y.; Ruigrok, E.; Gomez, M.; Draganov, D.S.

    2015-01-01

    We investigated the applicability of global phases (epicentral distances of ? 120° and ? 150°) for the H/V spectral ratio to identify the fundamental resonance frequency. We applied the method to delineate a part of Neuquén basin in Argentina without the need for active seismic sources. We obtained

  6. Infrared spectral studies of various metal polyacrylates

    International Nuclear Information System (INIS)

    McCluskey, P.H.; Snyder, R.L.; Condrate, R.A. Sr.

    1989-01-01

    A new process for the production of high surface area, high reactivity ceramic oxide powders involves the bonding of metal cations to polymeric polyacrylate chains. This process results in the formation of a gelatinous metal polyacrylate precipitate which can be easily removed from the mother liquor, and then calcined to form a high density ceramic oxide. Using FTIR spectroscopy, the nature of the structural arrangements has been studied for metal complexes in the yttrium, lanthanum, aluminum, cerium, copper, and iron polyacrylates. Interpretation of the infrared spectra indicates that two types of metal complex formation occur in these precipitates, involving bidentate or bridging interactions. The type that is observed for a particular metal ion is dependent on its metal ion size

  7. The percutaneous nephrolithotomy global study

    DEFF Research Database (Denmark)

    Labate, Gaston; Modi, Pranjal; Timoney, Anthony

    2011-01-01

    PCNL Global Study collected prospective data for consecutive patients who were treated with PCNL at centers around the world for 1 year. Complications were evaluated by the modified Clavien classification system. RESULTS: Of 5724 patients with Clavien scores, 1175 (20.5%) patients experienced one......PURPOSE: This study evaluated postoperative complications of percutaneous nephrolithotomy (PCNL) and the influence of selected factors on the risk of complications using the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study database. PATIENTS AND METHODS: The CROES...... grade I. Two patients died in the postoperative period. The largest absolute increases in mean Clavien score were associated with American Society of Anesthesiologists (ASA) physical status classification IV (0.75) or III (0.34), anticoagulant medication use (0.29), positive microbiologic culture from...

  8. A Scalable Version of the Navy Operational Global Atmospheric Prediction System Spectral Forecast Model

    Directory of Open Access Journals (Sweden)

    Thomas E. Rosmond

    2000-01-01

    Full Text Available The Navy Operational Global Atmospheric Prediction System (NOGAPS includes a state-of-the-art spectral forecast model similar to models run at several major operational numerical weather prediction (NWP centers around the world. The model, developed by the Naval Research Laboratory (NRL in Monterey, California, has run operational at the Fleet Numerical Meteorological and Oceanographic Center (FNMOC since 1982, and most recently is being run on a Cray C90 in a multi-tasked configuration. Typically the multi-tasked code runs on 10 to 15 processors with overall parallel efficiency of about 90%. resolution is T159L30, but other operational and research applications run at significantly lower resolutions. A scalable NOGAPS forecast model has been developed by NRL in anticipation of a FNMOC C90 replacement in about 2001, as well as for current NOGAPS research requirements to run on DOD High-Performance Computing (HPC scalable systems. The model is designed to run with message passing (MPI. Model design criteria include bit reproducibility for different processor numbers and reasonably efficient performance on fully shared memory, distributed memory, and distributed shared memory systems for a wide range of model resolutions. Results for a wide range of processor numbers, model resolutions, and different vendor architectures are presented. Single node performance has been disappointing on RISC based systems, at least compared to vector processor performance. This is a common complaint, and will require careful re-examination of traditional numerical weather prediction (NWP model software design and data organization to fully exploit future scalable architectures.

  9. Inferring global upper-mantle shear attenuation structure by waveform tomography using the spectral element method

    Science.gov (United States)

    Karaoǧlu, Haydar; Romanowicz, Barbara

    2018-06-01

    We present a global upper-mantle shear wave attenuation model that is built through a hybrid full-waveform inversion algorithm applied to long-period waveforms, using the spectral element method for wavefield computations. Our inversion strategy is based on an iterative approach that involves the inversion for successive updates in the attenuation parameter (δ Q^{-1}_μ) and elastic parameters (isotropic velocity VS, and radial anisotropy parameter ξ) through a Gauss-Newton-type optimization scheme that employs envelope- and waveform-type misfit functionals for the two steps, respectively. We also include source and receiver terms in the inversion steps for attenuation structure. We conducted a total of eight iterations (six for attenuation and two for elastic structure), and one inversion for updates to source parameters. The starting model included the elastic part of the relatively high-resolution 3-D whole mantle seismic velocity model, SEMUCB-WM1, which served to account for elastic focusing effects. The data set is a subset of the three-component surface waveform data set, filtered between 400 and 60 s, that contributed to the construction of the whole-mantle tomographic model SEMUCB-WM1. We applied strict selection criteria to this data set for the attenuation iteration steps, and investigated the effect of attenuation crustal structure on the retrieved mantle attenuation structure. While a constant 1-D Qμ model with a constant value of 165 throughout the upper mantle was used as starting model for attenuation inversion, we were able to recover, in depth extent and strength, the high-attenuation zone present in the depth range 80-200 km. The final 3-D model, SEMUCB-UMQ, shows strong correlation with tectonic features down to 200-250 km depth, with low attenuation beneath the cratons, stable parts of continents and regions of old oceanic crust, and high attenuation along mid-ocean ridges and backarcs. Below 250 km, we observe strong attenuation in the

  10. Integrated spectral study of small angular diameter galactic open clusters

    Science.gov (United States)

    Clariá, J. J.; Ahumada, A. V.; Bica, E.; Pavani, D. B.; Parisi, M. C.

    2017-10-01

    This paper presents flux-calibrated integrated spectra obtained at Complejo Astronómico El Leoncito (CASLEO, Argentina) for a sample of 9 Galactic open clusters of small angular diameter. The spectra cover the optical range (3800-6800 Å), with a resolution of ˜14 Å. With one exception (Ruprecht 158), the selected clusters are projected into the fourth Galactic quadrant (282o evaluate their membership status. The current cluster sample complements that of 46 open clusters previously studied by our group in an effort to gather a spectral library with several clusters per age bin. The cluster spectral library that we have been building is an important tool to tie studies of resolved and unresolved stellar content.

  11. Global approach to the spectral problem of microinstabilities in tokamak plasmas using a gyrokinetic model

    International Nuclear Information System (INIS)

    Brunner, S.

    1997-08-01

    Ion temperature gradient (ITG)-related instabilities are studied in tokamak-like plasmas with the help of a new global eigenvalue code. Ions are modelled in the frame of gyrokinetic theory so that finite Larmor radius effects of these particles are retained to all orders. Non-adiabatic trapped electron dynamics is taken into account through the bounce-averaged drift kinetic equation. Assuming electrostatic perturbations, the system is closed with the quasineutrality relation. Practical methods are presented which make this global approach feasible. These include a non-standard wave decomposition compatible with the curved geometry as well as adapting an efficient root finding algorithm for computing the unstable spectrum. These techniques are applied to a low pressure configuration given by a large aspect ratio torus with circular, concentric magnetic surfaces. Simulations from a linear, time evolution, particle in cell code provide a useful benchmark. Comparisons with local ballooning calculations for different parameter scans enable further validation while illustrating the limits of that representation at low toroidal wave numbers or for non-interchange-like instabilities. The stabilizing effect of negative magnetic shear is also considered, in which case the global results show not only an attenuation of the growth rate but also a reduction of the radial extent induced by a transition from the toroidal- to the slab-ITG mode. Contributions of trapped electrons to the ITG instability as well as the possible coupling to the trapped electron mode are clearly brought to the fore. (author) figs., tabs., 69 refs

  12. Estimation of spectral solar radiation based on global insolation and characteristics of spectral solar radiation on a tilt surface; Zenten nissharyo ni motozuku zenten nissha supekutoru no suitei to keishamen bunko tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Baba, H; Kanayama, K; Endo, N; Koromohara, K; Takayama, H [Kitami Institute of Technology, Hokkaido (Japan)

    1996-10-27

    Use of global insolation for estimating the corresponding spectral distribution is proposed. Measurements of global insolation spectrum throughout a year were compiled for clear days and cloudy days, ranked by 100W/m{sup 2}, for the clarification of spectral distribution. Global insolation quantity for a clear day was subject mainly to sun elevation. The global insolation spectral distribution with the sun elevation not lower than 15{degree} was similar to Bird`s model. Under the cloudy sky, energy density was lower in the region of wavelengths longer than the peak wavelength of 0.46{mu}m, and the distribution curve was sharper than that under the clear sky. Values given by Bird`s model were larger than measured values in the wavelength range of 0.6-1.8{mu}m, which was attributed to absorption by vapor. From the standard spectral distribution charts for the clear sky and cloudy sky, and from the dimensionless spectral distributions obtained by dividing them by the peak values, spectral distributions could be estimated of insolation quantities for the clear sky, cloudy sky, etc. As for the characteristics of spectral solar radiation on a tilt surface obtained from Bird`s model, they agreed with actually measured values at an angle of inclination of 60{degree} or smaller. 6 refs., 10 figs., 1 tab.

  13. Globalization, Justice, and Communication : A Critical Study of Global Ethics

    OpenAIRE

    Ehnberg, Jenny

    2015-01-01

    The purpose of this study is to seek to an answer to the question of what constitutes a tenable model for global ethics. This is done in part by a critical engagement with four different models of global ethics; two proposals from political philosophy and two contributions from theological ethics. The models analyzed in the study are: (1) the capabilities approach as developed by Martha Nussbaum, (2) Seyla Benhabib’s discourse ethics and model of cosmopolitan federalism, (3) David Hollenbach’...

  14. Global Infrared–Radio Spectral Energy Distributions of Galactic Massive Star-Forming Regions

    Science.gov (United States)

    Povich, Matthew Samuel; Binder, Breanna Arlene

    2018-01-01

    We present a multiwavelength study of 30 Galactic massive star-forming regions. We fit multicomponent dust, blackbody, and power-law continuum models to 3.6 µm through 10 mm spectral energy distributions obtained from Spitzer, MSX, IRAS, Herschel, and Planck archival survey data. Averaged across our sample, ~20% of Lyman continuum photons emitted by massive stars are absorbed by dust before contributing to the ionization of H II regions, while ~50% of the stellar bolometric luminosity is absorbed and reprocessed by dust in the H II regions and surrounding photodissociation regions. The most luminous, infrared-bright regions that fully sample the upper stellar initial mass function (ionizing photon rates NC ≥ 1050 s–1 and total infrared luminosity LTIR ≥ 106.8 L⊙) have higher percentages of absorbed Lyman continuum photons (~40%) and dust-reprocessed starlight (~80%). The monochromatic 70-µm luminosity L70 is linearly correlated with LTIR, and on average L70/LTIR = 50%, in good agreement with extragalactic studies. Calibrated against the known massive stellar content in our sampled H II regions, we find that star formation rates based on L70 are in reasonably good agreement with extragalactic calibrations, when corrected for the smaller physical sizes of the Galactic regions. We caution that absorption of Lyman continuum photons prior to contributing to the observed ionizing photon rate may reduce the attenuation-corrected Hα emission, systematically biasing extragalactic calibrations toward lower star formation rates when applied to spatially-resolved studies of obscured star formation.This work was supported by the National Science Foundation under award CAREER-1454333.

  15. Spectral and morphological study of galaxies with UV excess. VI

    International Nuclear Information System (INIS)

    Kazaryan, M.A.; Kazaryan, E.S.; Byurakan Astrophysical Observatory)

    1985-01-01

    Results are given of a spectral and morphological study of galaxies Nos. 73, 125, and 229. The masses are determined of the gaseous components of these galaxies. It is established that galaxy No. 73 is a type Sy 2 galaxy, and in its physical properties it resembles the Sy 2 type galaxies Markaryan 744 and 1066. In some of its physical properties galaxy No. 125 is similar to galaxy No. 73, but it is evidently at a later stage of development than the latter. The results show that these galaxies differ from one another both in their physical properties and in their external structure

  16. The global thermospheric mapping study

    International Nuclear Information System (INIS)

    Oliver, W.L.; Salah, J.E.

    1988-01-01

    The Global Thermospheric Mapping Study (GTMS) is a multitechnique experimental pilot study of the Earth's thermosphere designed to map simultaneously its spatial and temporal morphology. This paper provides the background for the study and presents the analysis techniques employed at Millstone Hill and results to date on thermospheric structure and dynamics. The first latitudinal-temporal maps of exospheric temperature obtained from the incoherent scatter radar chain at 70W meridian are presented for the two solstice periods, revealing substantial seasonal differences between them. The observed structure shows a relatively depressed temperature at high latitude in summer in contrast to the mass spectrometer/incoherent scatter 1983 [MSIS-83] empirical model, which shows a maximum temperature at polar latitudes. The MSIS-83 model predictions are in good agreement with the observed latitudinal-temporal structure in winter. Comparison with the numerical predictions made for the June 26-28, 1984 period with the National Center for Atmospheric Research thermospheric general circulation model shows reasonable agreement in the latitudinal gradient but the observations indicate a cooler thermosphere by several hundred degrees. Neutral winds at mid-latitudes are presented showing the expected strong southward winds at night, which are found to be consistent with the temperature gradients observed in the latitudinal maps. There is good agreement in the June winds between the available numerical model calculations and the observations. Work performed elsewhere on the GTMS data base is summarized for completeness

  17. Photometric and Spectral Study of the Saturnian Satellites

    Science.gov (United States)

    Newman, Sarah F.

    2005-01-01

    Photometric and spectra analysis of data from the Cassini Visual and Infrared Mapping Spectrometer (VIMS) has yielded intriguing findings regarding the surface properties of several of the icy Saturnian satellites. Spectral cubes were obtained of these satellites with a wavelength distribution in the IR far more extensive than from any previous observations. Disk-integrated solar phase curves were constructed in several key IR wavelengths that are indicative of key properties of the surface of the body, such as macroscopic roughness, fluffiness (or the porosity of the surface), global albedo and scattering properties of surface particles. Polynomial fits to these phase curves indicate a linear albedo trend of the curvature of the phase functions. Rotational phase functions from Enceladus were found to exhibit a double-peaked sinusoidal curve, which shows larger amplitudes for bands corresponding to water ice and a linear amplitude-albedo trend. These functions indicate regions on the surface of the satellite of more recent geologic activity. In addition, recent images of Enceladus show tectonic features and an absence of impact craters on Southern latitudes which could be indicative of a younger surface. Investigations into the properties of these features using VIMS are underway.

  18. Global sampling of the seasonal changes in vegetation biophysical properties and associated carbon flux dynamics: using the synergy of information captured by spectral time series

    Science.gov (United States)

    Campbell, P. K. E.; Huemmrich, K. F.; Middleton, E.; Voorhis, S.; Landis, D.

    2016-12-01

    Spatial heterogeneity and seasonal dynamics in vegetation function contribute significantly to the uncertainties in regional and global CO2 budgets. High spectral resolution imaging spectroscopy ( 10 nm, 400-2500 nm) provides an efficient tool for synoptic evaluation of the factors significantly affecting the ability of the vegetation to sequester carbon and to reflect radiation, due to changes in vegetation chemical and structural composition. EO-1 Hyperion has collected more than 15 years of repeated observations for vegetation studies, and currently Hyperion time series are available for study of vegetation carbon dynamics at a number of FLUX sites. This study presents results from the analysis of EO-1 Hyperion and FLUX seasonal composites for a range of ecosystems across the globe. Spectral differences and seasonal trends were evaluated for each vegetation type and specific phenology. Evaluating the relationships between CO2 flux parameters (e.g., Net ecosystem production - NEP; Gross Ecosystem Exchange - GEE, CO2 flux, μmol m-2 s-1) and spectral parameters for these very different ecosystems, high correlations were established to parameters associated with canopy water and chlorophyll content for deciduous, and photosynthetic function for conifers. Imaging spectrometry provided high spatial resolution maps of CO2 fluxes absorbed by vegetation, and was efficient in tracing seasonal flux dynamics. This study will present examples for key ecosystem tipes to demonstrate the ability of imaging spectrometry and EO-1 Hyperion to map and compare CO2 flux dynamics across the globe.

  19. [Study on spectral detection of green plant target].

    Science.gov (United States)

    Deng, Wei; Zhao, Chun-jiang; He, Xiong-kui; Chen, Li-ping; Zhang, Lu-da; Wu, Guang-wei; Mueller, J; Zhai, Chang-yuan

    2010-08-01

    Weeds grow scatteredly in fields, where many insentient objects exist, for example, withered grasses, dry twig and barriers. In order to improve the precision level of spraying, it is important to study green plant detecting technology. The present paper discussed detecting method of green plant by using spectral recognizing technology, because of the real-time feature of spectral recognition. By analyzing the reflectivity difference between each of the two sides of the "red edge" of the spectrum from plants and surrounding environment, green plant discriminat index (GPDI) is defined as the value which equals the reflectivity ratio at the wavelength of 850 nm divided by the reflectivity ratio at the wavelength of 650 nm. The original spectral data of green plants and the background were measured by using the handhold FieldSpec 3 Spectroradiometer manufactured by ASD Inc. in USA. The spectral data were processed to get the reflectivity of each measured objects and to work out the GPDI thereof as well. The classification model of green plant and its background was built up using decision tree method in order to obtain the threshold of GPDI to distinguish green plants and the background. The threshold of GPDI was chosen as 5.54. The detected object was recognized as green plant when it is GPDI>GPDITH, and vice versa. Through another test, the accuracy rate was verified which was 100% by using the threshold. The authors designed and developed the green plant detector based on single chip microcomputer (SCM) "AT89S51" and photodiode "OPT101" to realize detecting green plants from the background. After passing through two optical filters, the center wavelengths of which are 650 and 850 nm respectively, the reflected light from measured targets was detected by two photodiodes and converted into electrical signals. These analog signals were then converted to digital signals via an analog-to-digital converter (ADS7813) after being amplified by a signal amplifier (OP400

  20. Advances in Spectral Nodal Methods applied to SN Nuclear Reactor Global calculations in Cartesian Geometry

    International Nuclear Information System (INIS)

    Barros, R.C.; Filho, H.A.; Oliveira, F.B.S.; Silva, F.C. da

    2004-01-01

    Presented here are the advances in spectral nodal methods for discrete ordinates (SN) eigenvalue problems in Cartesian geometry. These coarse-mesh methods are based on three ingredients: (i) the use of the standard discretized spatial balance SN equations; (ii) the use of the non-standard spectral diamond (SD) auxiliary equations in the multiplying regions of the domain, e.g. fuel assemblies; and (iii) the use of the non-standard spectral Green's function (SGF) auxiliary equations in the non-multiplying regions of the domain, e.g., the reflector. In slab-geometry the hybrid SD-SGF method generates numerical results that are completely free of spatial truncation errors. In X,Y-geometry, we obtain a system of two 'slab-geometry' SN equations for the node-edge average angular fluxes by transverse-integrating the X,Y-geometry SN equations separately in the y- and then in the x-directions within an arbitrary node of the spatial grid set up on the domain. In this paper, we approximate the transverse leakage terms by constants. These are the only approximations considered in the SD-SGF-constant nodal method, as the source terms, that include scattering and eventually fission events, are treated exactly. Moreover, we describe in this paper the progress of the approximate SN albedo boundary conditions for substituting the non-multiplying regions around the nuclear reactor core. We show numerical results to typical model problems to illustrate the accuracy of spectral nodal methods for coarse-mesh SN criticality calculations. (Author)

  1. The spectral problem of global microinstabilities in tokamak-like plasmas using a gyrokinetic model

    International Nuclear Information System (INIS)

    Brunner, S.; Vaclavik, J.; Fivaz, M.; Appert, K.

    1996-01-01

    Tokamak-like plasmas are modeled by a periodic cylindrical system with magnetic shear and realistic density and temperature profiles. Linear electrostatic microinstabilities in such plasmas are studied by solving the eigenvalue problem starting from gyrokinetic theory. The actual eigenvalue equation is then of integral type. With this approach, finite Larmor radius (FLR) effects to all orders are taken into account. FLR effects provide for the only radial coupling in a cylinder and to lowest order correspond to polarization drift. This effectively one-dimensional problem helped us to gain useful knowledge for solving gyrokinetic equations in a curved system. When searching for the eigenfrequencies of the global modes, two different methods have been tested and compared. Either the true eigenvalue problem is solved by finding the zeros of the characteristic equation, or one considers a system driven by an antenna and looks for resonances in the power response of the plasma. In addition, mode structures were computed as well in direct as in Fourier space. The advantages and disadvantages of these various approaches are discussed. Ion temperature gradient (ITG) instabilities are studied over a wide range of parameters and for wavelengths perpendicular to the magnetic field down to the scale of ion Larmor radii. Flute instabilities driven by magnetic curvature drifts are also considered. Some of these results are compared with a time evolution PIC code. Such comparisons are valuable as the convergence of PIC results is often questioned. Work considering true toroidal geometry is in progress

  2. Syntheses and spectral studies of novel ciprofloxacin derivatives

    Directory of Open Access Journals (Sweden)

    Pradeep Yadav

    2008-12-01

    Full Text Available Reaction of 1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl-1,4-dihydroquinoline-3-carboxylic acid (ciprofloxacin with thiazole/benzothiazole diazonium chloride afforded piperazine substituted ciprofloxacin derivative. The acid part of these derivatives was further condensed with various β-diketones to get 1-cyclopropyl-6-fluoro-4-oxo-7-(4-(thiazol-2-yldiazenylpiperazin-1-yl-1,4-dihydroquinoline-3-carboxylic acid derivatives (5a-e and 7-(4-(benzo[d]thiazol-2-yldiazenylpiperazin-1-yl-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid derivatives (5f-j. Structures of these compounds were established on the basis of spectral studies.

  3. Synthesis and Spectral Study of Novel Norfloxacin Derivatives

    Directory of Open Access Journals (Sweden)

    Pradeep Yadav

    2008-01-01

    Full Text Available Reaction of [1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl-quinolone-3-carboxylic acid (norfloxacin with thiazole / benzothiazole diazonium chloride to get new piperazine substituted norfloxacin derivative. These norfloxacin derivatives were further condensed with various β-diketone to get novel acid derivatives of 1-Ethyl-6-fluoro-4-oxo-7- [4 (thiazol-2-yldiazenyl-piperzin-1-yl]-1,4-dihydro-quinoline-3-carboxylic acid (6a-e and 7-(4-(benzo[d]thiazol-2-yldiazenylpiperazin-1-yl-1-ethyl-6-fluoro-4-oxo-1, 4-dihydroquinoline-3-carboxylic acid (6 f-j. Structures of these compounds were established on the basis of spectral studies viz. IR, 1H NMR etc.

  4. Global analysis studies and applications

    CERN Document Server

    Gliklikh, Yuri; Vershik, A

    1992-01-01

    This volume (a sequel to LNM 1108, 1214, 1334 and 1453) continues the presentation to English speaking readers of the Voronezh University press series on Global Analysis and Its Applications. The papers are selected fromtwo Russian issues entitled "Algebraic questions of Analysis and Topology" and "Nonlinear Operators in Global Analysis". CONTENTS: YuE. Gliklikh: Stochastic analysis, groups of diffeomorphisms and Lagrangian description of viscous incompressible fluid.- A.Ya. Helemskii: From topological homology: algebras with different properties of homological triviality.- V.V. Lychagin, L.V. Zil'bergleit: Duality in stable Spencer cohomologies.- O.R. Musin: On some problems of computational geometry and topology.- V.E. Nazaikinskii, B.Yu. Sternin, V.E.Shatalov: Introduction to Maslov's operational method (non-commutative analysis and differential equations).- Yu.B. Rudyak: The problem of realization of homology classes from Poincare up to the present.- V.G. Zvyagin, N.M. Ratiner: Oriented degree of Fredholm...

  5. Studying soil properties using visible and near infrared spectral analysis

    Science.gov (United States)

    Moretti, S.; Garfagnoli, F.; Innocenti, L.; Chiarantini, L.

    2009-04-01

    This research is carried out inside the DIGISOIL Project, whose purposes are the integration and improvement of in situ and proximal measurement technologies, for the assessment of soil properties and soil degradation indicators, going form the sensing technologies to their integration and their application in digital soil mapping. The study area is located in the Virginio river basin, about 30 km south of Firenze, in the Chianti area, where soils with agricultural suitability have a high economic value connected to the production of internationally famous wines and olive oils. The most common soil threats, such as erosion and landslide, may determine huge economic losses, which must be considered in farming management practices. This basin has a length of about 23 km for a basin area of around 60,3 Km2. Geological formations outcropping in the area are Pliocene to Pleistocene marine and lacustrine sediments in beds with almost horizontal bedding. Vineyards, olive groves and annual crops are the main types of land use. A typical Mediterranean climate prevails with a dry summer followed by intense and sometimes prolonged rainfall in autumn, decreasing in winter. In this study, three types of VNIR and SWIR techniques, operating at different scales and in different environments (laboratory spectroscopy, portable field spectroscopy) are integrated to rapidly quantify various soil characteristics, in order to acquire data for assessing the risk of occurrence for typically agricultural practice-related soil threats (swelling, compaction, erosion, landslides, organic matter decline, ect.) and to collect ground data in order to build up a spectral library to be used in image analysis from air-borne and satellite sensors. Difficulties encountered in imaging spectroscopy, such as influence of measurements conditions, atmospheric attenuation, scene dependency and sampling representation are investigated and mathematical pre-treatments, using proper algorithms, are applied and

  6. Spectral studies of new fullerene-tetrathiafulvalene based system

    International Nuclear Information System (INIS)

    Laskowska, Barbara; Lapinski, Andrzej; Graja, Andrzej; Hudhomme, Pietrick

    2007-01-01

    Molecular and electronic structures as well as electronic and vibrational spectra of compounds 1-3 were investigated. The spectra were recorded in the large spectral range from 400 to 50,000 cm -1 ; our interest was focused on the electronic excitations of both moieties of the dyad and the intramolecular vibrations of the dyad's components. With the help of the Gaussian 03 program, molecular geometry, electron structure and normal mode analysis for the dyad and/or reference compounds were studied. An assignment of the main vibrational bands of the dyad and its reference molecules was made taking into consideration their IR and Raman spectra as well as results of the normal mode analysis. In principle, the intramolecular vibrations typical for C 60 and tetrathiafulvalene (TTF) derivatives can be found in the spectra of the dyad; the bands' frequencies are insignificantly shifted comparing with the separated molecules but their shape is usually modified. It suggests that symmetry and molecular structure of both components of the dyad are rather kept after dyad's formation but redistribution of charges occurs

  7. Spectral and time-resolved studies on ocular structures

    Science.gov (United States)

    Schweitzer, D.; Jentsch, S.; Schenke, S.; Hammer, M.; Biskup, C.; Gaillard, E.

    2007-07-01

    Measurements of endogeous fluorophores open the possibility for evaluation of metabolic state at the eye. For interpretation of 2-dimensional measurements of time-resolved auto fluorescence in 2 separate spectral ranges at the human eye, comparing measurements were performed on porcine eyes. Determining excitation and emission spectra, attention was drawn of proof of coenzymes NADH and FAD in isolated anatomical structures cornea, aqueous humor, lens, vitreous, neuronal retina, retinal pigment epithelium (RPE), choroid, and sclera. All these structures exhibit auto fluorescence, highest in lens. Excitation at 350 nm results in local fluorescence maxima at 460 nm, corresponding to NADH, in all structures. This short-wave excitation allows metabolic studies only at the anterior eye, because of the limited transmission of the ocular media. During excitation at 446 nm the existence of FAD is expressed by local fluorescence maxima at 530 nm. The composition fluorescence spectra allow no discrimination between single ocular structures. Approximating the dynamic fluorescence by a double exponential function, the shortest lifetimes were detected in RPE and neuronal retina. The histograms of mean lifetime t M cover each other on lens with cornea and also on sclera with choroid. Despite the lifetimes are close between RPE and neuronal retina, the relative contributions Q I are wide different. The gradient of trend lines in cluster diagrams of amplitudes α II vs. α I allows a discrimination of ocular structures.

  8. Spectral response of the coral rubble, living corals, and dead corals: study case on the Spermonde Archipelago, Indonesia

    Science.gov (United States)

    Nurdin, Nurjannah; Komatsu, Teruhisa; Yamano, Hiroya; Arafat, Gulam; Rani, Chair; Akbar AS, M.

    2012-10-01

    Coral reefs play important ecological services such as providing foods, biodiversity, nutrient recycling etc. for human society. On the other hand, they are threatened by human impacts such as illegal fishing and environmental changes such as rises of sea water temperature and sea level due to global warming. Thus, it is very important to monitor dynamic spatial distributions of coral reefs and related habitats such as coral rubble, dead coral, bleached corals, seagrass, etc. Hyperspectral data, in particular, offer high potential for characterizing and mapping coral reefs because of their capability to identify individual reef components based on their detailed spectral response. We studied the optical properties by measuring in situ spectra of living corals, dead coral and coral rubble covered with algae. Study site was selected in Spermonde archipelago, South Sulawesi, Indonesia because this area is included in the highest diversity of corals in the world named as Coral Triangle, which is recognized as the global centre of marine biodiversity and a global priority for conservation. Correlation analysis and cluster analysis support that there are distinct differences in reflectance spectra among categories. Common spectral characteristic of living corals, dead corals and coral rubble covered with algae was a reflectance minimum at 674 nm. Healthy corals, dead coral covered with algae and coral rubble covered with algae showed high similarity of spectral reflectance. It is estimated that this is due to photsynthetic pigments.

  9. An ERIC Update on Global Studies.

    Science.gov (United States)

    Cohen, Cheryl B.

    1987-01-01

    Reviews eight curriculum units, published between 1983 and 1986, for teaching global studies to K through 12 students. The units focus on global economics, problem solving, cultural awareness, hunger in developing nations, the influence of mass media, and ecological/political issues. (JDH)

  10. Global Studies: Hurdles to Program Development

    Science.gov (United States)

    Campbell, Patricia J.; Masters, Paul E.; Goolsby, Amy

    2004-01-01

    In this article, we examine a new global studies program that departs from the traditional state-centric approach and uses a geocentric, or earth-centered, approach that emphasizes the roles of individuals, grassroots organizations, cultural groups, and international organizations in an attempt to help students conceptualize global events and…

  11. Spectral dependence efficiency and localization of non-inductive current-drive via helicity injection by global Alfven waves in Tokamak plasmas

    International Nuclear Information System (INIS)

    Komoshvili, K.; Cuperman, S.; Bruma, C.

    1996-01-01

    The non-inductive current drive via helicity injection by Global Alfven eigenmode (GAE) waves is studied. For illustration, the first radial mode of the discrete resonant GAE spectrum is considered. The following aspects are given special attention: spectral analysis, radial dependence and efficiency - all these as functions of the characteristics of the waves launched by an external, concentric antenna (i.e, wave frequency and poloidal and toroidal wave numbers). The results reveal the following conclusions. Generation of GAE waves. In the range of poloidal wave numbers -3 0 for m = -l, -2, -3 and -20 10; I-BAR < 0 for m = +1, +2, +3 and n < 10. (iv) The efficiency of the current drive, η = absolute I-BAR/absolute P-BAR, increases in the cases m = -1, -2, -3 with absolute m and absolute 1/n. (v) Detailed information on the relative direction and radial (core) localization of the current drive is obtained. (authors)

  12. Economic Study of Global Tobacco Burden

    Science.gov (United States)

    In an interview on Cancer Currents, Dr. Mark Parascandola discusses findings from an economics study showing that, globally, tobacco use burdens economies with more than US $1 trillion annually in health care costs and lost productivity.

  13. Probabilistic modeling and global sensitivity analysis for CO 2 storage in geological formations: a spectral approach

    KAUST Repository

    Saad, Bilal Mohammed

    2017-09-18

    This work focuses on the simulation of CO2 storage in deep underground formations under uncertainty and seeks to understand the impact of uncertainties in reservoir properties on CO2 leakage. To simulate the process, a non-isothermal two-phase two-component flow system with equilibrium phase exchange is used. Since model evaluations are computationally intensive, instead of traditional Monte Carlo methods, we rely on polynomial chaos (PC) expansions for representation of the stochastic model response. A non-intrusive approach is used to determine the PC coefficients. We establish the accuracy of the PC representations within a reasonable error threshold through systematic convergence studies. In addition to characterizing the distributions of model observables, we compute probabilities of excess CO2 leakage. Moreover, we consider the injection rate as a design parameter and compute an optimum injection rate that ensures that the risk of excess pressure buildup at the leaky well remains below acceptable levels. We also provide a comprehensive analysis of sensitivities of CO2 leakage, where we compute the contributions of the random parameters, and their interactions, to the variance by computing first, second, and total order Sobol’ indices.

  14. Probabilistic modeling and global sensitivity analysis for CO 2 storage in geological formations: a spectral approach

    KAUST Repository

    Saad, Bilal Mohammed; Alexanderian, Alen; Prudhomme, Serge; Knio, Omar

    2017-01-01

    This work focuses on the simulation of CO2 storage in deep underground formations under uncertainty and seeks to understand the impact of uncertainties in reservoir properties on CO2 leakage. To simulate the process, a non-isothermal two-phase two-component flow system with equilibrium phase exchange is used. Since model evaluations are computationally intensive, instead of traditional Monte Carlo methods, we rely on polynomial chaos (PC) expansions for representation of the stochastic model response. A non-intrusive approach is used to determine the PC coefficients. We establish the accuracy of the PC representations within a reasonable error threshold through systematic convergence studies. In addition to characterizing the distributions of model observables, we compute probabilities of excess CO2 leakage. Moreover, we consider the injection rate as a design parameter and compute an optimum injection rate that ensures that the risk of excess pressure buildup at the leaky well remains below acceptable levels. We also provide a comprehensive analysis of sensitivities of CO2 leakage, where we compute the contributions of the random parameters, and their interactions, to the variance by computing first, second, and total order Sobol’ indices.

  15. A spectral radioluminescence study for dating and dosimetry

    International Nuclear Information System (INIS)

    Krbetschek, M.R.; Trautmann, T.

    2000-01-01

    The spectral distribution of radioluminescence (RL) and its dose dependence was investigated on various substances to get information about the applicability in dosimetry and dating. The list comprises archaeometallurgical slag components (quartz relicts, glassy fraction), bone, cooking salt, corals, egg shell, flint, mussel shell, natural gypsum, natural halite, quartz (sediments, vein quartz) and sugar. The different emission wave-bands and basic features of their RL-dose-characteristics are reported for 18 different samples. Furthermore results of some materials are discussed in more detail

  16. Characterizing the Purple Earth: Modeling the globally integrated spectral variability of the Archean Earth

    International Nuclear Information System (INIS)

    Sanromá, E.; Pallé, E.; López, R.; Montañés-Rodríguez, P.; Parenteau, M. N.; Kiang, N. Y.; Gutiérrez-Navarro, A. M.

    2014-01-01

    Ongoing searches for exoplanetary systems have revealed a wealth of planets with diverse physical properties. Planets even smaller than the Earth have already been detected and the efforts of future missions are aimed at the discovery, and perhaps characterization, of small rocky exoplanets within the habitable zone of their stars. Clearly, what we know about our planet will be our guideline for the characterization of such planets. However, the Earth has been inhabited for at least 3.8 Gyr and its appearance has changed with time. Here, we have studied the Earth during the Archean eon, 3.0 Gyr ago. At that time, one of the more widespread life forms on the planet was purple bacteria. These bacteria are photosynthetic microorganisms and can inhabit both aquatic and terrestrial environments. Here, we use a radiative transfer model to simulate the visible and near-infrared radiation reflected by our planet, taking into account several scenarios regarding the possible distribution of purple bacteria over continents and oceans. We find that purple bacteria have a reflectance spectrum that has a strong reflectivity increase, similar to the red edge of leafy plants, although shifted redward. This feature produces a detectable signal in the disk-averaged spectra of our planet, depending on cloud amount and purple bacteria concentration/distribution. We conclude that by using multi-color photometric observations, it is possible to distinguish between an Archean Earth in which purple bacteria inhabit vast extensions of the planet and a present-day Earth with continents covered by deserts, vegetation, or microbial mats.

  17. GLOBAL SOURCING: A THEORETICAL STUDY ON TURKEY

    Directory of Open Access Journals (Sweden)

    Aytac GOKMEN

    2010-07-01

    Full Text Available Global sourcing is to source from the global market for goods and services across national boundaries in order to take advantage of the global efficiencies in the delivery of a product or service. Such efficiencies are consists of low cost skilled labor, low cost raw materials and other economic factors like tax breaks and deductions as well as low trade tariffs. When we assess the case regarding to Turkey, global sourcing is an effective device for some firms. The domestic firms in Turkey at various industries are inclined to global source finished or intermediate goods from the world markets, finish the production process in Turkey and export. Eventually, on the one hand the export volume of Turkey increases, but on the other hand the import of a considerable volume of finished or intermediate goods bring about a negative trade balance and loss of jobs in Turkey. Therefore, the objective of this study is to assess the concept of global sourcing transactions on Turkey resting on comprehensive publications.

  18. A global assessment of market accessibility and market influence for global environmental change studies

    NARCIS (Netherlands)

    Verburg, P.H.; Ellis, E.C.; Letourneau, A.

    2011-01-01

    Markets influence the global patterns of urbanization, deforestation, agriculture and other land use systems. Yet market influence is rarely incorporated into spatially explicit global studies of environmental change, largely because consistent global data are lacking below the national level. Here

  19. Social Studies Within A Global Education.

    Science.gov (United States)

    Kniep, Willard M.

    1986-01-01

    Maintains that the extraordinary privileges and responsibilities attached to contemporary and future United States citizenship demands a more global approach to social studies. Proposes four essential elements and three major themes to set the boundary for the scope of the social studies. Provides an illustrative example of appropriate grade level…

  20. Study the Characterization of Spectral Absorbance on Irradiated Milk Protein

    Science.gov (United States)

    Fohely, F.; Suardi, N.

    2018-04-01

    The milk has been adopted as a structural nature food for a long era since it is containing most of the growth factors, protective agents, and enzymes needed for the body. a few attempts have been conducted to treat the dairy products especially raw milk by the means of ionizing radiation. as its production has been an expanding industry for many years due to the high demands from the consumers worldwide, there is still some doubt about preserving these products by irradiation. In this work, a preliminary effort to describe the influences of ionizing radiation on raw milk’s protein will be devoted to measuring the spectral absorbance of the total protein (after subjected to varied radiation doses) by UV-VIS-NIR spectroscopy analysis. The absorbance spectrum then analyzed based on absorbance spectra of organic compounds. A comparison is made between the effects of different radiation doses to estimate the influence in milk’s structure.

  1. Global Leadership Study: A Theoretical Framework

    Science.gov (United States)

    Perkins, Anne W.

    2009-01-01

    Traditional leadership theory and research courses do not adequately prepare students for cross-cultural leadership. This article notes six premises of Western theories and demonstrates the limitations of these premises in non-Western settings. A framework for the study of cross-cultural leadership, The Global Leadership-Learning Pyramid, is…

  2. Earth Matters: Studies for Our Global Future.

    Science.gov (United States)

    Wasserman, Pamela; Doyle, Andrea

    Through 12 readings and 32 activities this curriculum material introduces high school students to issues of the global environment and society, while both challenging them to critically evaluate the issues and motivating them to develop solutions. The materials are cited as being applicable to social studies, science, math, language arts, and…

  3. Spectral studies of Lanthanide interactions with membrane surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Karukstis, K.K.; Kao, M.Y.; Savin, D.A.; Bittker, R.A.; Kaphengst, K.J.; Emetarom, C.M.; Naito, N.R.; Takamoto, D.Y. [Harvey Mudd College, Claremont, CA (United States)

    1995-03-23

    We have monitored the interactions of the series of trivalent lanthanide cations with the thylakoid membrane surface of spinach chloroplasts using two complementary spectral techniques. Measurements of the fluorescence emission of the extrinsic probe 2-p-toluidinonaphthalene-6-sulfonate (TNS) and the absorbance of the intrinsic chromophore chlorophyll provide two sensitive means of characterizing the dependence of the cation-membrane interaction on the nature of the cation. In these systems, added lanthanide cations adsorb onto the membrane surface to neutralize exposed segments of membrane-embedded protein complexes. The lanthanide-induced charge neutralization increases the proximity of added TNS anion to the membrane surface as evidenced by variations in the TNS fluorescence level and wavelength of maximum emission. Our results reveal a strong dependence of TNS fluorescence parameters on both lanthanide size and total orbital angular momentum L value. Lanthanides with greater charge density (small size and/or low L value) enhance the TNS fluorescence level to a greater extent. A possible origin for the lanthanide-dependent TNS fluorescence levels is suggested in terms of a heterogeneity in the number and type of TNS binding sites. The data are consistent with the proposal that larger lanthanides with smaller enthalpies of hydration induce more significant membrane appression. 59 refs., 9 figs., 2 tabs.

  4. The use of spectral methods in bidomain studies.

    Science.gov (United States)

    Trayanova, N; Pilkington, T

    1992-01-01

    A Fourier transform method is developed for solving the bidomain coupled differential equations governing the intracellular and extracellular potentials on a finite sheet of cardiac cells undergoing stimulation. The spectral formulation converts the system of differential equations into a "diagonal" system of algebraic equations. Solving the algebraic equations directly and taking the inverse transform of the potentials proved numerically less expensive than solving the coupled differential equations by means of traditional numerical techniques, such as finite differences; the comparison between the computer execution times showed that the Fourier transform method was about 40 times faster than the finite difference method. By application of the Fourier transform method, transmembrane potential distributions in the two-dimensional myocardial slice were calculated. For a tissue characterized by a ratio of the intra- to extracellular conductivities that is different in all principal directions, the transmembrane potential distribution exhibits a rather complicated geometrical pattern. The influence of the different anisotropy ratios, the finite tissue size, and the stimuli configuration on the pattern of membrane polarization is investigated.

  5. Global meta-analysis of transcriptomics studies.

    Directory of Open Access Journals (Sweden)

    José Caldas

    Full Text Available Transcriptomics meta-analysis aims at re-using existing data to derive novel biological hypotheses, and is motivated by the public availability of a large number of independent studies. Current methods are based on breaking down studies into multiple comparisons between phenotypes (e.g. disease vs. healthy, based on the studies' experimental designs, followed by computing the overlap between the resulting differential expression signatures. While useful, in this methodology each study yields multiple independent phenotype comparisons, and connections are established not between studies, but rather between subsets of the studies corresponding to phenotype comparisons. We propose a rank-based statistical meta-analysis framework that establishes global connections between transcriptomics studies without breaking down studies into sets of phenotype comparisons. By using a rank product method, our framework extracts global features from each study, corresponding to genes that are consistently among the most expressed or differentially expressed genes in that study. Those features are then statistically modelled via a term-frequency inverse-document frequency (TF-IDF model, which is then used for connecting studies. Our framework is fast and parameter-free; when applied to large collections of Homo sapiens and Streptococcus pneumoniae transcriptomics studies, it performs better than similarity-based approaches in retrieving related studies, using a Medical Subject Headings gold standard. Finally, we highlight via case studies how the framework can be used to derive novel biological hypotheses regarding related studies and the genes that drive those connections. Our proposed statistical framework shows that it is possible to perform a meta-analysis of transcriptomics studies with arbitrary experimental designs by deriving global expression features rather than decomposing studies into multiple phenotype comparisons.

  6. Global Monitoring of Terrestrial Chlorophyll Fluorescence from Moderate-spectral-resolution Near-infrared Satellite Measurements: Methodology, Simulations, and Application to GOME-2

    Science.gov (United States)

    Joiner, J.; Gaunter, L.; Lindstrot, R.; Voigt, M.; Vasilkov, A. P.; Middleton, E. M.; Huemmrich, K. F.; Yoshida, Y.; Frankenberg, C.

    2013-01-01

    Globally mapped terrestrial chlorophyll fluorescence retrievals are of high interest because they can provide information on the functional status of vegetation including light-use efficiency and global primary productivity that can be used for global carbon cycle modeling and agricultural applications. Previous satellite retrievals of fluorescence have relied solely upon the filling-in of solar Fraunhofer lines that are not significantly affected by atmospheric absorption. Although these measurements provide near-global coverage on a monthly basis, they suffer from relatively low precision and sparse spatial sampling. Here, we describe a new methodology to retrieve global far-red fluorescence information; we use hyperspectral data with a simplified radiative transfer model to disentangle the spectral signatures of three basic components: atmospheric absorption, surface reflectance, and fluorescence radiance. An empirically based principal component analysis approach is employed, primarily using cloudy data over ocean, to model and solve for the atmospheric absorption. Through detailed simulations, we demonstrate the feasibility of the approach and show that moderate-spectral-resolution measurements with a relatively high signal-to-noise ratio can be used to retrieve far-red fluorescence information with good precision and accuracy. The method is then applied to data from the Global Ozone Monitoring Instrument 2 (GOME-2). The GOME-2 fluorescence retrievals display similar spatial structure as compared with those from a simpler technique applied to the Greenhouse gases Observing SATellite (GOSAT). GOME-2 enables global mapping of far-red fluorescence with higher precision over smaller spatial and temporal scales than is possible with GOSAT. Near-global coverage is provided within a few days. We are able to show clearly for the first time physically plausible variations in fluorescence over the course of a single month at a spatial resolution of 0.5 deg × 0.5 deg

  7. Global monitoring of terrestrial chlorophyll fluorescence from moderate-spectral-resolution near-infrared satellite measurements: methodology, simulations, and application to GOME-2

    Directory of Open Access Journals (Sweden)

    J. Joiner

    2013-10-01

    Full Text Available Globally mapped terrestrial chlorophyll fluorescence retrievals are of high interest because they can provide information on the functional status of vegetation including light-use efficiency and global primary productivity that can be used for global carbon cycle modeling and agricultural applications. Previous satellite retrievals of fluorescence have relied solely upon the filling-in of solar Fraunhofer lines that are not significantly affected by atmospheric absorption. Although these measurements provide near-global coverage on a monthly basis, they suffer from relatively low precision and sparse spatial sampling. Here, we describe a new methodology to retrieve global far-red fluorescence information; we use hyperspectral data with a simplified radiative transfer model to disentangle the spectral signatures of three basic components: atmospheric absorption, surface reflectance, and fluorescence radiance. An empirically based principal component analysis approach is employed, primarily using cloudy data over ocean, to model and solve for the atmospheric absorption. Through detailed simulations, we demonstrate the feasibility of the approach and show that moderate-spectral-resolution measurements with a relatively high signal-to-noise ratio can be used to retrieve far-red fluorescence information with good precision and accuracy. The method is then applied to data from the Global Ozone Monitoring Instrument 2 (GOME-2. The GOME-2 fluorescence retrievals display similar spatial structure as compared with those from a simpler technique applied to the Greenhouse gases Observing SATellite (GOSAT. GOME-2 enables global mapping of far-red fluorescence with higher precision over smaller spatial and temporal scales than is possible with GOSAT. Near-global coverage is provided within a few days. We are able to show clearly for the first time physically plausible variations in fluorescence over the course of a single month at a spatial resolution of 0

  8. A Study of Spectral Integration and Normalization in NMR-based Metabonomic Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Webb-Robertson, Bobbie-Jo M.; Lowry, David F.; Jarman, Kristin H.; Harbo, Sam J.; Meng, Quanxin; Fuciarelli, Alfred F.; Pounds, Joel G.; Lee, Monica T.

    2005-09-15

    Metabonomics involves the quantitation of the dynamic multivariate metabolic response of an organism to a pathological event or genetic modification (Nicholson, Lindon and Holmes, 1999). The analysis of these data involves the use of appropriate multivariate statistical methods. Exploratory Data Analysis (EDA) linear projection methods, primarily Principal Component Analysis (PCA), have been documented as a valuable pattern recognition technique for 1H NMR spectral data (Brindle et al., 2002, Potts et al., 2001, Robertson et al., 2000, Robosky et al., 2002). Prior to PCA the raw data is typically processed through four steps; (1) baseline correction, (2) endogenous peak removal, (3) integration over spectral regions to reduce the number of variables, and (4) normalization. The effect of the size of spectral integration regions and normalization has not been well studied. We assess the variability structure and classification accuracy on two distinctly different datasets via PCA and a leave-one-out cross-validation approach under two normalization approaches and an array of spectral integration regions. This study indicates that independent of the normalization method the classification accuracy achieved from metabonomic studies is not highly sensitive to the size of the spectral integration region. Additionally, both datasets scaled to mean zero and unity variance (auto-scaled) has higher variability within classification accuracy over spectral integration window widths than data scaled to the total intensity of the spectrum.

  9. Satellite Contributions to Global Change Studies

    Science.gov (United States)

    Parkinson, Claire L.

    2009-01-01

    sophisticated climate models, in situ process studies, and data sets that extend back well before the introduction of satellite technology. Nonetheless, the repetitive, global view provided by satellites is contributing in a major way to our improved recognition of how the Earth im changing, a recognition that is none too soon in view of the magnitude of the impacts that humans can now have.

  10. Globalization and neighbourhood values: a study of akwete ndoki in ...

    African Journals Online (AJOL)

    Globalization and neighbourhood values: a study of akwete ndoki in abia state of ... global connectivity, integration and interdependence in the economic, social, ... This paper tries to examine the effect of globalization on neighbourhood ...

  11. A Guide to Curriculum Planning in Global Studies.

    Science.gov (United States)

    Hartoonian, H. Michael; Stock, Hilary

    This guide is designed to assist educators develop curricula to embrace global perspectives. The guide is organized into five sections. The first section provides an overview of global studies, and seeks to answer such questions as "Why study global studies?" and "What does global studies include?" The second section identifys…

  12. Realization and study of spectral properties of the ISGRI gamma-ray camera

    International Nuclear Information System (INIS)

    Limousin, O.

    2001-11-01

    This work evaluates spectroscopic and physical properties of CdTe detectors in view of assembling a large number on a new generation spectro-imager for space gamma-ray astronomy. Study, optimization, realization and calibration of modular detection units of the ISGRI camera are described. After a description of the experimental context of the INTEGRAL program and a review of the physical processes involved in gamma-ray photon detectors, we present an analysis of the properties of CdTe detectors attempting to be so exhaustive as possible. We propose the base point of a global model, which relates charge transport properties, spectral response and possible instabilities in the detectors. We propose a new formulation of the Hecht relation that describes charge loss as a function of the detector charge transport properties. We discuss at length the method of charge loss correction and its consequences on the associated integrated electronics definition. Finally, we illustrate our instrument capabilities using as an example the observation of titanium 44 lines in historical supernovae. (author)

  13. Realization and study of spectral properties of the ISGRI gamma-ray camera; Mise en oeuvre et etude des proprietes spectrales de la gamma-camera ISGRI

    Energy Technology Data Exchange (ETDEWEB)

    Limousin, O

    2001-11-01

    This work evaluates spectroscopic and physical properties of CdTe detectors in view of assembling a large number on a new generation spectro-imager for space gamma-ray astronomy. Study, optimization, realization and calibration of modular detection units of the ISGRI camera are described. After a description of the experimental context of the INTEGRAL program and a review of the physical processes involved in gamma-ray photon detectors, we present an analysis of the properties of CdTe detectors attempting to be so exhaustive as possible. We propose the base point of a global model, which relates charge transport properties, spectral response and possible instabilities in the detectors. We propose a new formulation of the Hecht relation that describes charge loss as a function of the detector charge transport properties. We discuss at length the method of charge loss correction and its consequences on the associated integrated electronics definition. Finally, we illustrate our instrument capabilities using as an example the observation of titanium 44 lines in historical supernovae. (author)

  14. Study of land surface temperature and spectral emissivity using multi ...

    Indian Academy of Sciences (India)

    tral emissivities over a hard rock terrain using multi-sensor satellite data. The study area, of .... Georeferenced MODIS level 1B data (bands 31 and. 32) and Landsat ETM+ data .... the optical properties of the atmosphere. In the present study ...

  15. Synthesis and spectral studies of some lanthanide(III) complexes ...

    African Journals Online (AJOL)

    ... compounds were characterized through various physico-chemical studies. The coordinating ligand DABAAPS behave as tridentate N,N,O-donors. The central metal ion displays the coordination number nine in these complexes. Thermal stabilities of these complexes were also studied through thermogravimetric analysis.

  16. ASTER spectral sensitivity of carbonate rocks - Study in Sultanate of Oman

    Science.gov (United States)

    Rajendran, Sankaran; Nasir, Sobhi

    2014-02-01

    Remote sensing satellite data plays a vital role and capable in detecting minerals and discriminating rock types for explorations of mineral resources and geological studies. Study of spectral absorption characters of remotely sensed data are under consideration by the exploration and mining companies, and demonstrating the spectral absorption characters of carbonates on the cost-effective multispectral image (rather than the hyperspectral, Lidar image) for easy understanding of all geologists and exploration communities of carbonates is very much important. The present work is an integrated study and an outcome of recently published works on the economic important carbonate rocks, includes limestone, marl, listwaenites and carbonatites occurred in parts of the Sultanate of Oman. It demonstrates the spectral sensitivity of such rocks for simple interpretation over satellite data and describes and distinguishes them based on the absorptions of carbonate minerals in the spectral bands of advanced spaceborne thermal emission and reflection radiometer (ASTER) for mapping and exploration studies. The study results that the ASTER spectral band 8 discriminates the carbonate rocks due to the presence of predominantly occurred carbonate minerals; the ASTER band 5 distinguishes the limestones and marls (more hydroxyl clay minerals) from listwaenite (hydrothermally altered rock) due to the presence of altered minerals and the ASTER band 4 detects carbonatites (ultramafic intrusive alkaline rocks) which contain relatively more silicates. The study on the intensity of the total absorptions against the reflections of these rocks shows that the limestones and marls have low intensity in absorptions (and high reflection values) due to the presence of carbonate minerals (calcite and dolomite) occurred in different proportions. The listwaenites and carbonatites have high intensity of absorptions (low reflection values) due to the occurrence of Mn-oxide in listwaenites and carbonates

  17. Syntheses, magnetic and spectral studies on polystyrene supported ...

    Indian Academy of Sciences (India)

    Unknown

    DMF results in the formation of polystyrene-anchored monobasic bidentate Schiff base, ... studied ligands in coordination chemistry. On ac- count of their pronounced coordinating properties, a ... Experimental ... temperature and then was suction-filtered, washed .... vent due to its high dielectric constant and its ability.

  18. Far-infrared spectral studies of magnesium and aluminum co ...

    Indian Academy of Sciences (India)

    Far-infrared absorption spectroscopy has been used to study the occurrence of var- ... density of the products was found to be about 83% of the X-ray density. ..... [15] B D Cullity, Elements of X-ray diffraction (Addison-Wesley Press, Reading, ...

  19. Statistical Study of Turbulence: Spectral Functions and Correlation Coefficients

    Science.gov (United States)

    Frenkiel, Francois N.

    1958-01-01

    In reading the publications on turbulence of different authors, one often runs the risk of confusing the various correlation coefficients and turbulence spectra. We have made a point of defining, by appropriate concepts, the differences which exist between these functions. Besides, we introduce in the symbols a few new characteristics of turbulence. In the first chapter, we study some relations between the correlation coefficients and the different turbulence spectra. Certain relations are given by means of demonstrations which could be called intuitive rather than mathematical. In this way we demonstrate that the correlation coefficients between the simultaneous turbulent velocities at two points are identical, whether studied in Lagrange's or in Euler's systems. We then consider new spectra of turbulence, obtained by study of the simultaneous velocities along a straight line of given direction. We determine some relations between these spectra and the correlation coefficients. Examining the relation between the spectrum of the turbulence measured at a fixed point and the longitudinal-correlation curve given by G. I. Taylor, we find that this equation is exact only when the coefficient is very small.

  20. Uranyl soaps - thermal, electronic and infrared spectral study

    International Nuclear Information System (INIS)

    Solanki, A.K.; Bhandari, A.M.

    1981-01-01

    The electronic and infrared spectra and TGA thermogram of uranyl soaps (laurate, mystrate, palmitate and stearate) have been studied. The environment about the UO 2+ 2 ion would comprise two 'short bite' bidentate carboxylate groups and oxygen atoms bridging from adjacent carboxylic molecules. The uranyl soaps have UO 2+ 2 vibronic absorption (approx. equal to 22730 cm -1 ) in the range found for eight coordinate uranyl complexes. The greater resistance to thermal degradation (approx. equal to 300 0 C) of these soaps and their stepwise thermal degradation infer strong metal-ligand interaction. (orig.) [de

  1. Numerical Simulations of Kinetic Alfvén Waves to Study Spectral ...

    Indian Academy of Sciences (India)

    Numerical Simulations of Kinetic Alfvén Waves to Study Spectral. Index in Solar Wind Turbulence and Particle Heating. R. P. Sharma. ∗. & H. D. Singh. Center for Energy Studies, Indian Institute of Technology, Delhi 110 016, India. ∗ e-mail: rpsharma@ces.iitd.ernet.in. Abstract. We present numerical simulations of the ...

  2. Growth, spectral and thermal studies of ibuprofen crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ramukutty, S.; Ramachandran, E. [Department of Physics, Thiruvalluvar College, Papanasam (India)

    2012-01-15

    RS -Ibuprofen was crystallized for the first time in silica gel under suitable pH conditions by reduction of solubility method. The grown crystals were characterized by single crystal X-ray diffraction and density measurement. The functional groups present in the crystal were identified using Fourier transform infrared spectroscopy. Optical bandgap energy of ibuprofen was estimated as 3.19(3) eV from UV-Vis spectrum. Thermogravimetric analysis revealed that ibuprofen is thermally stable upto 102.9 C and the initial loss of mass was due to evaporation only. Morphological study showed that the growth is prominent along b-axis and the prominent face is {l_brace}100{r_brace}. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Earthquake Source Spectral Study beyond the Omega-Square Model

    Science.gov (United States)

    Uchide, T.; Imanishi, K.

    2017-12-01

    Earthquake source spectra have been used for characterizing earthquake source processes quantitatively and, at the same time, simply, so that we can analyze the source spectra for many earthquakes, especially for small earthquakes, at once and compare them each other. A standard model for the source spectra is the omega-square model, which has the flat spectrum and the falloff inversely proportional to the square of frequencies at low and high frequencies, respectively, which are bordered by a corner frequency. The corner frequency has often been converted to the stress drop under the assumption of circular crack models. However, recent studies claimed the existence of another corner frequency [Denolle and Shearer, 2016; Uchide and Imanishi, 2016] thanks to the recent development of seismic networks. We have found that many earthquakes in areas other than the area studied by Uchide and Imanishi [2016] also have source spectra deviating from the omega-square model. Another part of the earthquake spectra we now focus on is the falloff rate at high frequencies, which will affect the seismic energy estimation [e.g., Hirano and Yagi, 2017]. In June, 2016, we deployed seven velocity seismometers in the northern Ibaraki prefecture, where the shallow crustal seismicity mainly with normal-faulting events was activated by the 2011 Tohoku-oki earthquake. We have recorded seismograms at 1000 samples per second and at a short distance from the source, so that we can investigate the high-frequency components of the earthquake source spectra. Although we are still in the stage of discovery and confirmation of the deviation from the standard omega-square model, the update of the earthquake source spectrum model will help us systematically extract more information on the earthquake source process.

  4. Measuring Globalization: Existing Methods and Their Implications for Teaching Global Studies and Forecasting

    Science.gov (United States)

    Zinkina, Julia; Korotayev, Andrey; Andreev, Aleksey I.

    2013-01-01

    Purpose: The purpose of this paper is to encourage discussions regarding the existing approaches to globalization measurement (taking mainly the form of indices and rankings) and their shortcomings in terms of applicability to developing Global Studies curricula. Another aim is to propose an outline for the globalization measurement methodology…

  5. Spectral studies of coordination compounds of cobalt(II) with thiosemicarbazone of heterocyclic ketone

    Science.gov (United States)

    Chandra, Sulekh; Kumar, Umendra

    2005-12-01

    The paper presents the spectral analysis of cobalt(II) complexes with indoxyl thiosemicarbazone (ITSC) of general composition [CoL 2X 2] (where L = ITSC, X = Cl -, NO 3-, (1/2)SO 42-, NCS -). The geometry of the complexes have been characterized by elemental analysis, molar conductance, magnetic susceptibility measurements and spectral (electronic, IR, EPR, 1H NMR, mass) studies. The various physico-chemical techniques suggested a coordination number of six (octahedral) for chloro, nitrato and thiocyanato complexes. Whereas sulfato complex was found to have five coordinate trigonal-bipyramidal geometry. All the complexes are of high spin type showing magnetic moment corresponding to three unpaired electrons.

  6. Spectral dependence, efficiency and localization of non-inductive current drive via helicity injection by global Alfven waves in tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Komoshvili, K.; Cuperman, S.; Bruma, C. [Tel Aviv Univ. (Israel). Sackler Faculty of Exact Sciences

    1997-04-01

    A systematic study of non-inductive current drive via helicity injection by global Alfven eigenmode (GAE) waves is carried out. For illustration, the first radial mode of the discrete resonant GAE spectrum is considered. The following aspects are given special attention: spectral analysis, radial dependence and efficiency - all of these functions of the characteristics of the waves launched by an external, concentric antenna (i.e. wave frequency and poloidal and toroidal wavenumbers). The tokamak plasma is simulated by a current-carrying cylindrical plasma column surrounded by a helical sheet current and situated inside a perfectly conducting shell, with incorporation of equilibrium (simulated) toroidal field, magnetic shear and a relatively large poloidal magnetic field component. Within the framework of low-{beta} MHD model equations and for typical tokamak physical parameters, the following basic results are obtained: (1) in the range of poloidal wavenumbers -3{<=} m {<=} 3 and toroidal wavenumbers -20{<=} n {<=}20, resonant GAE peaks below the Alfven continuum are found; (2) the power absorption (P), current drive (I) and corresponding frequency of the GAE modes depend strongly on the sets of (m,n) values considered; (3) the `net` current drive is positive (i.e. flows in the direction of the equilibrium current j{sub 0z} for m = -1, -2, -3 and -20 {<=} n {<=} -1 as well as for m +1, +2, +3 and n > 10); (4) in the cases m = -1, -2, -3, the efficiency of current drive, I/P, increases with /m/ and I/n/; (5) the radial localization of the current drive in each of the cases considered is determined and tabulated. (Author).

  7. Spectral dependence, efficiency and localization of non-inductive current drive via helicity injection by global Alfven waves in tokamak plasmas

    International Nuclear Information System (INIS)

    Komoshvili, K.; Cuperman, S.; Bruma, C.

    1997-01-01

    A systematic study of non-inductive current drive via helicity injection by global Alfven eigenmode (GAE) waves is carried out. For illustration, the first radial mode of the discrete resonant GAE spectrum is considered. The following aspects are given special attention: spectral analysis, radial dependence and efficiency - all of these functions of the characteristics of the waves launched by an external, concentric antenna (i.e. wave frequency and poloidal and toroidal wavenumbers). The tokamak plasma is simulated by a current-carrying cylindrical plasma column surrounded by a helical sheet current and situated inside a perfectly conducting shell, with incorporation of equilibrium (simulated) toroidal field, magnetic shear and a relatively large poloidal magnetic field component. Within the framework of low-β MHD model equations and for typical tokamak physical parameters, the following basic results are obtained: (1) in the range of poloidal wavenumbers -3≤ m ≤ 3 and toroidal wavenumbers -20≤ n ≤20, resonant GAE peaks below the Alfven continuum are found; (2) the power absorption (P), current drive (I) and corresponding frequency of the GAE modes depend strongly on the sets of (m,n) values considered; (3) the 'net' current drive is positive (i.e. flows in the direction of the equilibrium current j 0z for m = -1, -2, -3 and -20 ≤ n ≤ -1 as well as for m +1, +2, +3 and n > 10; (4) in the cases m = -1, -2, -3, the efficiency of current drive, I/P, increases with /m/ and I/n/; (5) the radial localization of the current drive in each of the cases considered is determined and tabulated. (Author)

  8. Study of the spectral and energy characteristics of lasing in the green spectral region by lithium fluoride with radiation color centers

    Energy Technology Data Exchange (ETDEWEB)

    Voitovich, A.P.; Kalinov, V.S.; Mikhnov, S.A.; Ovseichuk, S.I.

    1987-06-01

    The spectral and energy characteristics of lasers utilizing lithium fluoride with F2 and F3(+) color centers in transverse and longitudinal pumping schemes are studied. The feasibility of obtaining stable narrow-band radiation in the 510-570 nm range using a selective resonator is demonstrated. Consideration is given to the effect of lithium-fluoride crystal processing by excimer laser radiation at a wavelength of 308 nm on the spectroscopic and lasing characteristics of the F3(+) color center. After this processing, the laser efficiency in the green spectral region increases by more than a factor of two (reaching an efficiency of 14 percent). 7 references.

  9. A spectral nodal method for eigenvalue S{sub N} transport problems in two-dimensional rectangular geometry for energy multigroup nuclear reactor global calculations

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Davi Jose M.; Alves Filho, Hermes; Barros, Ricardo C., E-mail: davijmsilva@yahoo.com.br, E-mail: halves@iprj.uerj.br, E-mail: rcbarros@pq.cnpq.br [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Programa de Pos-Graduacao em Modelagem Computacional

    2015-07-01

    A spectral nodal method is developed for multigroup x,y-geometry discrete ordinates (S{sub N}) eigenvalue problems for nuclear reactor global calculations. This method uses the conventional multigroup SN discretized spatial balance nodal equations with two non-standard auxiliary equations: the spectral diamond (SD) auxiliary equations for the discretization nodes inside the fuel regions, and the spectral Green's function (SGF) auxiliary equations for the non-multiplying regions, such as the baffle and the reactor. This spectral nodal method is derived from the analytical general solution of the SN transverse integrated nodal equations with constant approximations for the transverse leakage terms within each discretization node. The SD and SGF auxiliary equations have parameters, which are determined to preserve the homogeneous and the particular components of these local general solutions. Therefore, we refer to the offered method as the hybrid SD-SGF-Constant Nodal (SD-SGF-CN) method. The S{sub N} discretized spatial balance equations, together with the SD and the SGF auxiliary equations form the SD-SGF-CN equations. We solve the SD-SGF-CN equations by using the one-node block inversion inner iterations (NBI), wherein the most recent estimates for the incoming group node-edge average or prescribed boundary conditions are used to evaluate the outgoing group node-edge average fluxes in the directions of the S{sub N} transport sweeps, for each estimate of the dominant eigenvalue in the conventional Power outer iterations. We show in numerical calculations that the SD-SGF-CN method is very accurate for coarse-mesh multigroup S{sub N} eigenvalue problems, even though the transverse leakage terms are approximated rather simply. (author)

  10. A spectral nodal method for eigenvalue SN transport problems in two-dimensional rectangular geometry for energy multigroup nuclear reactor global calculations

    International Nuclear Information System (INIS)

    Silva, Davi Jose M.; Alves Filho, Hermes; Barros, Ricardo C.

    2015-01-01

    A spectral nodal method is developed for multigroup x,y-geometry discrete ordinates (S N ) eigenvalue problems for nuclear reactor global calculations. This method uses the conventional multigroup SN discretized spatial balance nodal equations with two non-standard auxiliary equations: the spectral diamond (SD) auxiliary equations for the discretization nodes inside the fuel regions, and the spectral Green's function (SGF) auxiliary equations for the non-multiplying regions, such as the baffle and the reactor. This spectral nodal method is derived from the analytical general solution of the SN transverse integrated nodal equations with constant approximations for the transverse leakage terms within each discretization node. The SD and SGF auxiliary equations have parameters, which are determined to preserve the homogeneous and the particular components of these local general solutions. Therefore, we refer to the offered method as the hybrid SD-SGF-Constant Nodal (SD-SGF-CN) method. The S N discretized spatial balance equations, together with the SD and the SGF auxiliary equations form the SD-SGF-CN equations. We solve the SD-SGF-CN equations by using the one-node block inversion inner iterations (NBI), wherein the most recent estimates for the incoming group node-edge average or prescribed boundary conditions are used to evaluate the outgoing group node-edge average fluxes in the directions of the S N transport sweeps, for each estimate of the dominant eigenvalue in the conventional Power outer iterations. We show in numerical calculations that the SD-SGF-CN method is very accurate for coarse-mesh multigroup S N eigenvalue problems, even though the transverse leakage terms are approximated rather simply. (author)

  11. Fluorescence spectral studies of Gum Arabic: Multi-emission of Gum Arabic in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Dhenadhayalan, Namasivayam, E-mail: ndhena@gmail.com [Department of Chemistry, National Taiwan University, Taipei, Taiwan (China); Mythily, Rajan, E-mail: rajanmythily@gmail.com [Department of Chemistry, Dwaraka Doss Goverdhan Doss Vaishnav College (Autonomous), 833, Gokul Bagh, E.V.R. Periyar Road, Arumbakkam, Chennai 600 106 (India); Kumaran, Rajendran, E-mail: kumaranwau@rediffmail.com [Department of Chemistry, Dwaraka Doss Goverdhan Doss Vaishnav College (Autonomous), 833, Gokul Bagh, E.V.R. Periyar Road, Arumbakkam, Chennai 600 106 (India)

    2014-11-15

    Gum Arabic (GA), a food hydrocolloid is a natural composite obtained from the stems and branches of Acacia Senegal and Acacia Seyal trees. GA structure is made up of highly branched arabinogalactan polysaccharides. Steady-state absorption, fluorescence, and time-resolved fluorescence spectral studies of acid hydrolyzed GA solutions were carried out at various pH conditions. The fluorescence in GA is predominantly attributed to the presence of tyrosine and phenylalanine amino acids. The presence of multi-emissive peaks at different pH condition is attributed to the exposure of the fluorescing amino acids to the aqueous phase, which contains several sugar units, hydrophilic and hydrophobic moieties. Time-resolved fluorescence studies of GA exhibits a multi-exponential decay with different fluorescence lifetime of varying amplitude which confirms that tyrosine is confined to a heterogeneous microenvironment. The existence of multi-emissive peaks with large variation in the fluorescence intensities were established by 3D emission contour spectral studies. The probable location of the fluorophore in a heterogeneous environment was further ascertained by constructing a time-resolved emission spectrum (TRES) and time-resolved area normalized emission spectrum (TRANES) plots. Fluorescence spectral technique is used as an analytical tool in understanding the photophysical properties of a water soluble complex food hydrocolloid containing an intrinsic fluorophore located in a multiple environment is illustrated. - Highlights: • The Manuscript deals with the steady state absorption, emission, fluorescence lifetime and time-resolved emission spectrum studies of Gum Arabic in aqueous medium at various pH conditions. • The fluorescence emanates from the tyrosine amino acid present in GA. • Change in pH results in marked variation in the fluorescence spectral properties of tyrosine. • Fluorescence spectral techniques are employed as a tool in establishing the

  12. Impact of spectral nudging and domain size in studies of RCM response to parameter modification

    Energy Technology Data Exchange (ETDEWEB)

    Separovic, Leo; Laprise, Rene [Universite du Quebec a Montreal, Centre pour l' Etude et la Simulation du Climat a l' Echelle Regionale (ESCER), Montreal, QC (Canada); Universite du Quebec a Montreal (UQAM), Montreal, QC (Canada); Elia, Ramon de [Universite du Quebec a Montreal, Centre pour l' Etude et la Simulation du Climat a l' Echelle Regionale (ESCER), Montreal, QC (Canada); Consortium Ouranos, Montreal, QC (Canada)

    2012-04-15

    The paper aims at finding an RCM configuration that facilitates studies devoted to quantifying RCM response to parameter modification. When using short integration times, the response of the time-averaged variables to RCM modification tend to be blurred by the noise originating in the lack of predictability of the instantaneous atmospheric states. Two ways of enhancing the signal-to-noise ratio are studied in this work: spectral nudging and reduction of the computational domain size. The approach followed consists in the analysis of the sensitivity of RCM-simulated seasonal averages to perturbations of two parameters controlling deep convection and stratiform condensation, perturbed one at a time. Sensitivity is analyzed within different simulation configurations obtained by varying domain size and using the spectral nudging option. For each combination of these factors multiple members of identical simulations that differ exclusively in initial conditions are also generated to provide robust estimates of the sensitivities (the signal) and sample the noise. Results show that the noise magnitude is decreased both by reduction of domain size and the spectral nudging. However, the reduction of domain size alters some sensitivity signals. When spectral nudging is used significant alterations of the signal are not found. (orig.)

  13. A global assessment of market accessibility and market influence for global environmental change studies

    Energy Technology Data Exchange (ETDEWEB)

    Verburg, Peter H [Institute for Environmental Studies, Amsterdam Global Change Institute, VU University Amsterdam, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands); Ellis, Erle C [Department of Geography and Environmental Systems, University of Maryland, Baltimore County, Baltimore, MD 21250 (United States); Letourneau, Aurelien, E-mail: Peter.Verburg@ivm.vu.nl [UMR 5175 Centre d' Ecologie Fonctionnelle and Evolutive, Centre National de la Recherche Scientifique, 1919 Route de Mende, 34293 Montpellier cedex 5 (France)

    2011-07-15

    Markets influence the global patterns of urbanization, deforestation, agriculture and other land use systems. Yet market influence is rarely incorporated into spatially explicit global studies of environmental change, largely because consistent global data are lacking below the national level. Here we present the first high spatial resolution gridded data depicting market influence globally. The data jointly represent variations in both market strength and accessibility based on three market influence indices derived from an index of accessibility to market locations and national level gross domestic product (purchasing power parity). These indices show strong correspondence with human population density while also revealing several distinct and useful relationships with other global environmental patterns. As market influence grows, the need for high resolution global data on market influence and its dynamics will become increasingly important to understanding and forecasting global environmental change.

  14. A global assessment of market accessibility and market influence for global environmental change studies

    Science.gov (United States)

    Verburg, Peter H.; Ellis, Erle C.; Letourneau, Aurelien

    2011-07-01

    Markets influence the global patterns of urbanization, deforestation, agriculture and other land use systems. Yet market influence is rarely incorporated into spatially explicit global studies of environmental change, largely because consistent global data are lacking below the national level. Here we present the first high spatial resolution gridded data depicting market influence globally. The data jointly represent variations in both market strength and accessibility based on three market influence indices derived from an index of accessibility to market locations and national level gross domestic product (purchasing power parity). These indices show strong correspondence with human population density while also revealing several distinct and useful relationships with other global environmental patterns. As market influence grows, the need for high resolution global data on market influence and its dynamics will become increasingly important to understanding and forecasting global environmental change.

  15. Globalization and its methodological discontents: Contextualizing globalization through the study of HIV/AIDS

    Science.gov (United States)

    2011-01-01

    There remains considerable discontent between globalization scholars about how to conceptualize its meaning and in regards to epistemological and methodological questions concerning how we can come to understand how these processes ultimately operate, intersect and transform our lives. This article argues that to better understand what globalization is and how it affects issues such as global health, we must take a differentiating approach, which focuses on how the multiple processes of globalization are encountered and informed by different social groups and with how these encounters are experienced within particular contexts. The article examines the heuristic properties of qualitative field research as a means to help better understand how the intersections of globalization are manifested within particular locations. To do so, the article focuses on three recent case studies conducted on globalization and HIV/AIDS and explores how these cases can help us to understand the contextual permutations involved within the processes of globalization. PMID:21861895

  16. Globalization and its methodological discontents: Contextualizing globalization through the study of HIV/AIDS

    Directory of Open Access Journals (Sweden)

    Labonté Ronald

    2011-08-01

    Full Text Available Abstract There remains considerable discontent between globalization scholars about how to conceptualize its meaning and in regards to epistemological and methodological questions concerning how we can come to understand how these processes ultimately operate, intersect and transform our lives. This article argues that to better understand what globalization is and how it affects issues such as global health, we must take a differentiating approach, which focuses on how the multiple processes of globalization are encountered and informed by different social groups and with how these encounters are experienced within particular contexts. The article examines the heuristic properties of qualitative field research as a means to help better understand how the intersections of globalization are manifested within particular locations. To do so, the article focuses on three recent case studies conducted on globalization and HIV/AIDS and explores how these cases can help us to understand the contextual permutations involved within the processes of globalization.

  17. A global assessment of market accessibility and market influence for global environmental change studies

    International Nuclear Information System (INIS)

    Verburg, Peter H; Ellis, Erle C; Letourneau, Aurelien

    2011-01-01

    Markets influence the global patterns of urbanization, deforestation, agriculture and other land use systems. Yet market influence is rarely incorporated into spatially explicit global studies of environmental change, largely because consistent global data are lacking below the national level. Here we present the first high spatial resolution gridded data depicting market influence globally. The data jointly represent variations in both market strength and accessibility based on three market influence indices derived from an index of accessibility to market locations and national level gross domestic product (purchasing power parity). These indices show strong correspondence with human population density while also revealing several distinct and useful relationships with other global environmental patterns. As market influence grows, the need for high resolution global data on market influence and its dynamics will become increasingly important to understanding and forecasting global environmental change.

  18. Novel plasma source for safe beryllium spectral line studies in the presence of beryllium dust

    Science.gov (United States)

    Stankov, B. D.; Vinić, M.; Gavrilović Božović, M. R.; Ivković, M.

    2018-05-01

    Plasma source for beryllium spectral line studies in the presence of beryllium dust particles was realised. The guideline during construction was to prevent exposure to formed dust, considering the toxicity of beryllium. Plasma source characterization through determination of optimal working conditions is described. The necessary conditions for Be spectral line appearance and optimal conditions for line shape measurements are found. It is proven experimentally that under these conditions dust appears coincidently with the second current maximum. The electron density measured after discharge current maximum is determined from the peak separation of the hydrogen Balmer beta spectral line, and the electron temperature is determined from the ratios of the relative intensities of Be spectral lines emitted from successive ionized stages of atoms. Maximum values of electron density and temperature are measured to be 9.3 × 1022 m-3 and 16 800 K, respectively. Construction details and testing of the BeO discharge tube in comparison with SiO2 and Al2O3 discharge tubes are also presented in this paper.

  19. Delineating gas bearing reservoir by using spectral decomposition attribute: Case study of Steenkool formation, Bintuni Basin

    Science.gov (United States)

    Haris, A.; Pradana, G. S.; Riyanto, A.

    2017-07-01

    Tectonic setting of the Bird Head Papua Island becomes an important model for petroleum system in Eastern part of Indonesia. The current exploration has been started since the oil seepage finding in Bintuni and Salawati Basin. The biogenic gas in shallow layer turns out to become an interesting issue in the hydrocarbon exploration. The hydrocarbon accumulation appearance in a shallow layer with dry gas type, appeal biogenic gas for further research. This paper aims at delineating the sweet spot hydrocarbon potential in shallow layer by applying the spectral decomposition technique. The spectral decomposition is decomposing the seismic signal into an individual frequency, which has significant geological meaning. One of spectral decomposition methods is Continuous Wavelet Transform (CWT), which transforms the seismic signal into individual time and frequency simultaneously. This method is able to make easier time-frequency map analysis. When time resolution increases, the frequency resolution will be decreased, and vice versa. In this study, we perform low-frequency shadow zone analysis in which the amplitude anomaly at a low frequency of 15 Hz was observed and we then compare it to the amplitude at the mid (20 Hz) and the high-frequency (30 Hz). The appearance of the amplitude anomaly at a low frequency was disappeared at high frequency, this anomaly disappears. The spectral decomposition by using CWT algorithm has been successfully applied to delineate the sweet spot zone.

  20. Spectral studies of ocean water with space-borne sensor SCIAMACHY using Differential Optical Absorption Spectroscopy (DOAS

    Directory of Open Access Journals (Sweden)

    M. Vountas

    2007-09-01

    Full Text Available Methods enabling the retrieval of oceanic parameter from the space borne instrumentation Scanning Imaging Absorption Spectrometer for Atmospheric ChartographY (SCIAMACHY using Differential Optical Absorption Spectroscopy (DOAS are presented. SCIAMACHY onboard ENVISAT measures back scattered solar radiation at a spectral resolution (0.2 to 1.5 nm. The DOAS method was used for the first time to fit modelled Vibrational Raman Scattering (VRS in liquid water and in situ measured phytoplankton absorption reference spectra to optical depths measured by SCIAMACHY. Spectral structures of VRS and phytoplankton absorption were clearly found in these optical depths. Both fitting approaches lead to consistent results. DOAS fits correlate with estimates of chlorophyll concentrations: low fit factors for VRS retrievals correspond to large chlorophyll concentrations and vice versa; large fit factors for phytoplankton absorption correspond with high chlorophyll concentrations and vice versa. From these results a simple retrieval technique taking advantage of both measurements is shown. First maps of global chlorophyll concentrations were compared to the corresponding MODIS measurements with very promising results. In addition, results from this study will be used to improve atmospheric trace gas DOAS-retrievals from visible wavelengths by including these oceanographic signatures.

  1. GLOBALIZATION AND NEIGHBOURHOOD VALUES: A STUDY OF ...

    African Journals Online (AJOL)

    examine the effect of globalization on neighbourhood values of the people of. Akwete Ndoki ... promote group solidarity and mutual welfare. ... urbanization, industrialization, formal education, modern technology and changing nature of work ...

  2. Effects of spectral complexity and sound duration on automatic complex-sound pitch processing in humans - a mismatch negativity study.

    Science.gov (United States)

    Tervaniemi, M; Schröger, E; Saher, M; Näätänen, R

    2000-08-18

    The pitch of a spectrally rich sound is known to be more easily perceived than that of a sinusoidal tone. The present study compared the importance of spectral complexity and sound duration in facilitated pitch discrimination. The mismatch negativity (MMN), which reflects automatic neural discrimination, was recorded to a 2. 5% pitch change in pure tones with only one sinusoidal frequency component (500 Hz) and in spectrally rich tones with three (500-1500 Hz) and five (500-2500 Hz) harmonic partials. During the recordings, subjects concentrated on watching a silent movie. In separate blocks, stimuli were of 100 and 250 ms in duration. The MMN amplitude was enhanced with both spectrally rich sounds when compared with pure tones. The prolonged sound duration did not significantly enhance the MMN. This suggests that increased spectral rather than temporal information facilitates pitch processing of spectrally rich sounds.

  3. Spectral discrimination of giant reed (Arundo donax L.): A seasonal study in riparian areas

    Science.gov (United States)

    Fernandes, Maria Rosário; Aguiar, Francisca C.; Silva, João M. N.; Ferreira, Maria Teresa; Pereira, José M. C.

    2013-06-01

    The giant reed (Arundo donax L.) is amongst the one hundred worst invasive alien species of the world, and it is responsible for biodiversity loss and failure of ecosystem functions in riparian habitats. In this work, field spectroradiometry was used to assess the spectral separability of the giant reed from the adjacent vegetation and from the common reed, a native similar species. The study was conducted at different phenological periods and also for the giant reed stands regenerated after mechanical cutting (giant reed_RAC). A hierarchical procedure using Kruskal-Wallis test followed by Classification and Regression Trees (CART) was used to select the minimum number of optimal bands that discriminate the giant reed from the adjacent vegetation. A new approach was used to identify sets of wavelengths - wavezones - that maximize the spectral separability beyond the minimum number of optimal bands. Jeffries Matusita and Bhattacharya distance were used to evaluate the spectral separability using the minimum optimal bands and in three simulated satellite images, namely Landsat, IKONOS and SPOT. Giant reed was spectrally separable from the adjacent vegetation, both at the vegetative and the senescent period, exception made to the common reed at the vegetative period. The red edge region was repeatedly selected, although the visible region was also important to separate the giant reed from the herbaceous vegetation and the mid infrared region to the discrimination from the woody vegetation. The highest separability was obtained for the giant reed_RAC stands, due to its highly homogeneous, dense and dark-green stands. Results are discussed by relating the phenological, morphological and structural features of the giant reed stands and the adjacent vegetation with their optical traits. Weaknesses and strengths of the giant reed spectral discrimination are highlighted and implications of imagery selection for mapping purposes are argued based on present results.

  4. Stereoselective synthesis and spectral studies of some benzotriazolylacetyl hydrazones of 3-alkyl-2,6-diarylpiperidin-4-ones

    Science.gov (United States)

    Pillai, M. Velayutham; Rajeswari, K.; Kumar, C. Udhaya; Krishnan, K. Gokula; Mahendran, S.; Ramalingan, C.; Nagarajan, E. R.; Vidhyasagar, T.

    2017-12-01

    An effort to include biologically potent benzotriazole nucleus into piperidine ring is achieved through hydrazone formation. The characterization of the synthesized compounds was carried out using FT-IR, 1H &13C NMR, 1H-1H COSY, 1H-13C COSY, NOESY spectral techniques and GC-Mass spectrum. The spectral assignments were done without ambiguity using 2D-NMR techniques. The conformational preference of the piperidine ring deduced from the spectral studies is 'chair'. The diastereotopic nature of the methylene protons/methyl groups present in the molecules is revealed clearly in their spectral pattern observed.

  5. A study of global sand seas

    Science.gov (United States)

    McKee, Edwin D.

    1979-01-01

    The birth of the idea that led to this publication on "Global Sand Seas" dates back to the late 1920's. At that time I was engaged in a study of the Coconino Sandstone of Arizona's Grand Canyon. Considerable controversy existed then as to whether this sandstone was a subaqueous deposit or was composed of wind-formed dunes. It became apparent that definitive literature was sparse or lacking on types of dunes, global distribution of these types, the mechanics of their development, the precise nature of their internal structure of cross-stratificiation, and the relation of wind systems to these sand forms. Especially lacking were data on criteria that could confidently be used in the recognition of ancient dunes. The common denominator in this publication is eolian sand bodies. Although the book is concerned primarily with desert sand seas, the subject matter is not restricted to deserts; it includes many references to deposits of coastal sand and to sand bodies in humid climates. Nor does the book deal exclusively with dunes, which, according to most definitions, involve mounds or hills. Many references are made to sand sheets, sand stringers, and other types of sand deposits that have no prominent topographic expression. All sand bodies accumulated by the action of wind are discussed. Chapters A-J of this publication are primarily topical. Chapters cover the grain texture, the color, and the structure of modern dunes and other eolian sands. Special treatment is given to the relation of wind data to dune interpretation, the evolution of form in current-deposited sand bodies as determined from experimental studies, and the discriminant analysis technique for differentiating between coastal and inland desert sands. This topical part of the publication also includes an analysis of criteria used in ancient deposits to interpret their eolian genesis and a consideration of economic application of the principles described, including a discussion of potentials and problems

  6. Comparative Study Between Support Vector Machines And Neural Networks For Lithological Discrimination Using Hyper spectral Data

    International Nuclear Information System (INIS)

    Naguib, A.M.; Abd Elwahab, M.S.; Farag, M.A.; Yahia, M.A.; Ramadan, H.H.

    2009-01-01

    Remote sensing hyper spectral data has many applications especially in the field of , earth science. Utilization of this technology has shown a rapid increase in many areas of economic and scientific significance. Hyper spectral sensors capture the detailed spectral signatures that uniquely characterize a great number of diverse surface materials. Classification, clustering, and visualization of these very high dimensional signatures need untraditional methods. Different approaches for spectral image interpretation have been studied using Artificial Neural Networks (ANNs) and Support Vector Machines (SVM) to meet the challenge of high dimensionality. The study used SVMs for geological mapping of hyper spectral imagery at Abu Zenima area, western Sinai, Egypt, the hyper spectral data has been captured in 2003 by Hyperion instrument on the United States Geological survey (USGS) Earth Observing 1 (EO-I) satellite. Precisely the study compares between the use of SVMs and a neural network built on the concept of SVMs, this network uses the Kernel-Adatron algorithm with the Gaussian kernel for the process of training. The SVMs also uses the Gaussian kernel with different bandwidths to enhance the performance of the interpretation process; the results are compared in details. The Neural Network was trained with four data sets, the first consists of 11310 samples, gives recognition rate of 84%, the second has 22620 samples, recognition rate was 91.5%; the third has 33930 samples, recognition rate was 94.6%; finally the fourth has 45240 samples, recognition rate of 99.2%. The previous results fall in comparison with the results of SVMs which use two algorithms for training the first is the one against one algorithm which gave a recognition rate of 84% for the first data set, a recognition rate of 76.9% for the second data set, a recognition rate of 95.2% for the third one and 98.5% for the fourth one. and the other is one against many algorithms which gave a recognition

  7. Fluorescence spectral studies on interaction of fluorescent probes with Bovine Serum Albumin (BSA)

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Kaushik, E-mail: ghoshfcy@iitr.ac.in; Rathi, Sweety; Arora, Deepshikha

    2016-07-15

    Interaction of 2-(1-(naphthale-1-ylimino)ethyl)phenol (1), 2-methoxy-4-(((4-methoxyphenyl)imino)methyl)phenol (2) and 2-methoxy-4-((naphthalene-1-ylimino)methyl)phenol (3) with Bovine Serum Albumin (BSA) was examined. Fluorescence spectral data were obtained from the probes by varying the concentration of BSA as well as from BSA by varying the concentration of probes. Synchronous fluorescence measurements were performed and binding constants of the probes were calculated. To understand mode of quenching, Stern–Volmer plot, absorption spectral studies and life time measurements were performed. Förster resonance energy transfer (FRET) was also scrutinized. - Highlights: • Schiff bases with pendant phenolato function and interaction with BSA. • Synchronous fluorescence studies and a preferred interaction with tryptophan. • Probable interaction of probes with Trp-213 residue in the hydrophobic cavity. • 1:1 binding stoichiometry of probes and BSA in Benesi–Hildebrand graph.

  8. Experimental study and numerical simulations of the spectral properties of XUV lasers pumped by collisional excitation

    International Nuclear Information System (INIS)

    Meng, L.

    2012-01-01

    -like Ar and quasi-steady state pumping in Ne-like Zn. Besides the accurate measurement of the temporal coherence of the laser in each case, we have studied the spectral behaviour when the laser is operated in the saturation regime and (in Ni-like Mo) when it is seeded with high-order harmonic radiation. We have also investigated the temporal behaviour of the Ni-like Mo transient XUV laser, using an ultrafast X-ray streak camera. Our linewidth measurements are compared with detailed numerical calculations including relevant broadening mechanisms as well as radiative transfer effects. The evolution of the spectral profile with amplification and saturation was studied for different plasma parameters, and corresponding Fourier-transform limit duration were evaluated.The shortest temporal coherence (i.e. the largest bandwidth) is measured for the quasi-steady state pumping XUV laser, which operates at the highest density and ionic temperature. (author)

  9. Enhacing spectral sintesis techniques with performance gestures using the violin as a case study

    OpenAIRE

    Pérez Carrillo, Alfonso Antonio

    2009-01-01

    In this work we investigate new sound synthesis techniques for imitating musical instruments using the violin as a case study. It is a multidisciplinary research, covering several fields such as spectral modeling, machine learning, analysis of musical gestures or musical acoustics. It addresses sound production with a very empirical approach, based on the analysis of performance gestures as well as on the measurement of acoustical properties of the violin. Based on the characteristics of the ...

  10. Study of the diffuse spectral series of boron-like atomic systems

    International Nuclear Information System (INIS)

    Lavin, C.; Martin, I.; Vallejo, M.J.

    1992-01-01

    The diffuse spectral series, 2S 2 np 2 P-2s 2 nd 2 D, of the boron isoelectronic sequence has been studied through a one-particle scheme, by explicitly treating only the active electron. Oscillator strengths for various transitions (n = 2,3; n' = 3-16) have been computed with the quantum defect and relativistic quantum defect formalisms, and results comparing very satisfactory with other theoretical data have been obtained

  11. Growth, spectral, dielectric and antimicrobial studies on 4-piperidinium carboxylamide picrate crystals

    Science.gov (United States)

    Dhanabal, T.; Tharanitharan, V.; Amirthaganesan, G.; Dhandapani, M.

    2014-07-01

    Single crystal of 4-piperidinium carboxylamide picrate was grown by slow evaporation solution growth technique at ambient temperature. The average dimensions of grown crystal were 0.7 × 0.3 × 0.2 cm3. The solubility of the compound was analyzed using methanol and acetone. Optical property of the compound was ascertained by UV-visible absorption spectral study. The sharp and well defined Bragg peaks observed in the powder X-ray diffraction pattern confirm its crystallinity. The different kinds of protons and carbons in the compound were confirmed by 1H and 13C NMR spectral analyses. The presence of various functional groups in the compound was assigned through polarized Raman spectral study. The mechanical property of the crystal was measured by Vicker's microhardness test and the compound was found to be soft material. The dielectric constant and dielectric loss of the crystal decrease with increase in frequency. The antibacterial and antifungal activities of the crystal were studied by disc diffusion method and found that the compound shows good inhibition efficiency against various bacteria and fungi species.

  12. Globalizing Social Justice Education: The Case of The Global Solidarity Network Study e-Broad Program

    Science.gov (United States)

    Harrison, Yvonne D.; Kostic, Kevin; Toton, Suzanne C.; Zurek, Jerome

    2010-01-01

    This paper documents the development, implementation, and evaluation of "The Global Solidarity Network Study e-Broad Program (GSNSeBP)", an online social justice educational program that is blended into an onsite academic course. This global electronic program, which was developed through a partnership between Catholic Relief Services (CRS) and…

  13. Debating Globalization in Social Studies Education: Approaching Globalization Historically and Discursively

    Science.gov (United States)

    Agbaria, Ayman K.

    2011-01-01

    The purpose of this paper is to explore the dominant positions in the debates on globalization in American social studies education. Specifically, the paper illustrates that, first, globalization is conceived of as more of an unprecedented new age and less of a historical development. Second, it is conceived of as more of a natural process and…

  14. The global burden of dengue: an analysis from the Global Burden of Disease Study 2013

    NARCIS (Netherlands)

    J.D. Stanaway (Jeffrey D.); D.S. Shepard (Donald); E.A. Undurraga (Eduardo); Halasa, Y.A. (Yara A); L.E. Coffeng (Luc); Brady, O.J. (Oliver J); Hay, S.I. (Simon I); Bedi, N. (Neeraj); I.M. Bensenor (Isabela M.); C.A. Castañeda-Orjuela (Carlos A); T.-W. Chuang (Ting-Wu); K.B. Gibney (Katherine B); Z.A. Memish (Ziad); A. Rafay (Anwar); K.N. Ukwaja (Kingsley N); N. Yonemoto (Naohiro); C.J.L. Murray (Christopher)

    2016-01-01

    textabstractBackground Dengue is the most common arbovirus infection globally, but its burden is poorly quantified. We estimated dengue mortality, incidence, and burden for the Global Burden of Disease Study 2013. Methods We modelled mortality from vital registration, verbal autopsy, and

  15. Sustainable potato production: global case studies

    Science.gov (United States)

    Potato (Solanum tuberosum L.) is grown in over 100 countries throughout the world. As a staple food, potato is the fourth most important crop after rice, wheat, and maize, and has historically contributed to food and nutrition security in the world. Global interest in potato increased sharply in 200...

  16. Creating Global Citizens through Study Abroad

    Science.gov (United States)

    Bellamy, Carol; Weinberg, Adam

    2006-01-01

    One of the greatest challenges for a student today is how to live as a responsible citizen in a globalizing world. Today's interconnected world cannot afford bystanders or passive participants. It demands confident, skilled citizens who will make responsible choices that take into consideration how educators allocate resources and what impact…

  17. Temporal and spectral studies of high-order harmonics generated by polarization-modulated infrared fields

    International Nuclear Information System (INIS)

    Sola, I. J.; Zaier, A.; Cormier, E.; Mevel, E.; Constant, E.; Lopez-Martens, R.; Johnsson, P.; Varju, K.; Mauritsson, J.; L'Huillier, A.; Strelkov, V.

    2006-01-01

    The temporal confinement of high harmonic generation (HHG) via modulation of the polarization of the fundamental pulse is studied in both temporal and spectral domains. In the temporal domain, a collinear cross-correlation setup using a 40 fs IR pump for the HHG and a 9 fs IR pulse to probe the generated emission is used to measure the XUV pulse duration. The observed temporal confinement is found to be consistent with theoretical predictions. An increased confinement is observed when a 9 fs pulse is used to generate the harmonics. An important spectral broadening, including a continuum background, is also measured. Theoretical calculations show that with 10 fs driving pulses, either one or two main attosecond pulses are created depending on the value of the carrier envelope phase

  18. Spectral and photometric study of the symbiotic nova RS ophiuchus in quiet phase

    Science.gov (United States)

    Kondratyeva, L.; Rspaev, F.; Krugov, M.; Serebryanskiy, A.

    2017-07-01

    The results of spectral and photometric study of the recurrent Nova RS Ophiuchus are presented and discussed. Observations were carried out in 2009-2016. During these eight years the fluxes of HI and FeII emission lines have slightly decreased by a factor of 3 - 4. Hα and Hβ exhibit double-peaked profiles with a central absorption. The ratio of the blue and red peaks intensities(V/R) varies from 0.3 to 1.0 for Hβ and from 0.4 to 0.7 for Hα. Possible correlations between changes of the ratio and other spectral parameters were investigated. Dependence of V/R on the radial velocity of absorbtion component is found out.

  19. A spatially resolved radio spectral index study of the dwarf irregular galaxy NGC 1569

    Science.gov (United States)

    Westcott, Jonathan; Brinks, Elias; Hindson, Luke; Beswick, Robert; Heesen, Volker

    2018-04-01

    We study the resolved radio continuum spectral energy distribution of the dwarf irregular galaxy, NGC 1569, on a beam-by-beam basis to isolate and study its spatially resolved radio emission characteristics. Utilizing high-quality NRAO Karl G. Jansky Very Large Array observations that densely sample the 1-34 GHz frequency range, we adopt a Bayesian fitting procedure, where we use H α emission that has not been corrected for extinction as a prior, to produce maps of how the separated thermal emission, non-thermal emission, and non-thermal spectral index vary across NGC 1569's main disc. We find a higher thermal fraction at 1 GHz than is found in spiral galaxies (26^{+2}_{-3} {per cent}) and find an average non-thermal spectral index α = -0.53 ± 0.02, suggesting that a young population of cosmic ray electrons is responsible for the observed non-thermal emission. By comparing our recovered map of the thermal radio emission with literature H α maps, we estimate the total reddening along the line of sight to NGC 1569 to be E(B - V) = 0.49 ± 0.05, which is in good agreement with other literature measurements. Spatial variations in the reddening indicate that a significant portion of the total reddening is due to internal extinction within NGC 1569.

  20. A Moessbauer Spectral Study of the Hull Steel and Rusticles Recovered from the Titanic

    Energy Technology Data Exchange (ETDEWEB)

    Long, Gary J., E-mail: glong@umr.edu; Hautot, Dimitri [University of Missouri-Rolla, Department of Chemistry (United States); Grandjean, Fernande; Vandormael, D. [University of Liege, Institute of Physics, B5 (Belgium); Leighly, H. P. [University of Missouri-Rolla, Department of Metallurgical Engineering (United States)

    2004-09-15

    The recent recovery of steel from the Titanic has permitted a 295 K conversion electron Moessbauer spectral study of the Titanic hull plate steel oriented with the gamma-ray direction either perpendicular or parallel to the microstructural banding directions. The two spectra reveal virtually identical average orientations of the magnetization close to the plane of the plate. The hyperfine parameters are virtually identical to those of {alpha}-iron, a finding which agrees with the chemical analysis which reveals at most 0.21 wt% carbon corresponding to 3 wt% of cementite in pearlite. A 4.2 to 295 K transmission Moessbauer spectral study of the rusticles reveals small particles of geothite undergoing superparamagnetic relaxation with a blocking temperature of ca. 300 K. In addition approximately two percent of the Moessbauer spectral absorption area corresponds to a quadrupole doublet with hyperfine parameters typical of green rust. The identified iron containing components in therusticles agree with the powder X-ray diffraction results which reveal the predominant presence of small particles of poorly crystallized goethite and traces of quartz and green rust. An average size of 20{+-}5 nm for the goethite particles is obtained from both the average hyperfine field and the broadening of the X-ray diffraction peaks. The magnetic anisotropy constant of the goethite particles deduced from the hyperfine field and the particle size is 8x10{sup 3} J/m{sup 3}.

  1. Globalization

    Directory of Open Access Journals (Sweden)

    Tulio Rosembuj

    2006-12-01

    Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  2. Globalization

    OpenAIRE

    Tulio Rosembuj

    2006-01-01

    There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  3. [Study of near infrared spectral preprocessing and wavelength selection methods for endometrial cancer tissue].

    Science.gov (United States)

    Zhao, Li-Ting; Xiang, Yu-Hong; Dai, Yin-Mei; Zhang, Zhuo-Yong

    2010-04-01

    Near infrared spectroscopy was applied to measure the tissue slice of endometrial tissues for collecting the spectra. A total of 154 spectra were obtained from 154 samples. The number of normal, hyperplasia, and malignant samples was 36, 60, and 58, respectively. Original near infrared spectra are composed of many variables, for example, interference information including instrument errors and physical effects such as particle size and light scatter. In order to reduce these influences, original spectra data should be performed with different spectral preprocessing methods to compress variables and extract useful information. So the methods of spectral preprocessing and wavelength selection have played an important role in near infrared spectroscopy technique. In the present paper the raw spectra were processed using various preprocessing methods including first derivative, multiplication scatter correction, Savitzky-Golay first derivative algorithm, standard normal variate, smoothing, and moving-window median. Standard deviation was used to select the optimal spectral region of 4 000-6 000 cm(-1). Then principal component analysis was used for classification. Principal component analysis results showed that three types of samples could be discriminated completely and the accuracy almost achieved 100%. This study demonstrated that near infrared spectroscopy technology and chemometrics method could be a fast, efficient, and novel means to diagnose cancer. The proposed methods would be a promising and significant diagnosis technique of early stage cancer.

  4. Spectral phasor analysis of LAURDAN fluorescence in live A549 lung cells to study the hydration and time evolution of intracellular lamellar body-like structures

    DEFF Research Database (Denmark)

    Malacrida, Leonel; Astrada, Soledad; Briva, Arturo

    2016-01-01

    Using LAURDAN spectral imaging and spectral phasor analysis we concurrently studied the growth and hydration state of subcellular organelles (lamellar body-like, LB-like) from live A549 lung cancer cells at different post-confluence days. Our results reveal a time dependent two-step process...... governing the size and hydration of these intracellular LB-like structures. Specifically, a first step (days 1 to 7) is characterized by an increase in their size, followed by a second one (days 7 to 14) where the organelles display a decrease in their global hydration properties. Interestingly, our results...... also show that their hydration properties significantly differ from those observed in well-characterized artificial lamellar model membranes, challenging the notion that a pure lamellar membrane organization is present in these organelles at intracellular conditions. Finally, these LB-like structures...

  5. Growth, morphology, spectral and thermal studies of gel grown diclofenac acid crystals

    Science.gov (United States)

    Ramachandran, E.; Ramukutty, S.

    2014-03-01

    The crystal growth of diclofenac acid in silica gel is the first to be reported in literature. The growth parameters were varied to optimize the suitable growth condition. Single crystal X-ray diffraction method was used for the conformation of the crystal structure. Morphology studies showed that the growth is prominent along the b-axis and the prominent face is {002}. Fourier transform infrared spectral study was performed to identify the functional groups present in the crystal. Thermal stability and decomposition of the material were analyzed using thermo calorimetry in the temperature range 30-500 °C.

  6. In-vivo studies of new vector velocity and adaptive spectral estimators in medical ultrasound

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Lindskov

    2010-01-01

    New ultrasound techniques for blood flow estimation have been investigated in-vivo. These are vector velocity estimators (Transverse Oscillation, Synthetic Transmit Aperture, Directional Beamforming and Plane Wave Excitation) and adaptive spectral estimators (Blood spectral Power Capon and Blood...

  7. Spectral unmixing: estimating partial abundances

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2009-01-01

    Full Text Available techniques is complicated when considering very similar spectral signatures. Iron-bearing oxide/hydroxide/sulfate minerals have similar spectral signatures. The study focuses on how could estimates of abundances of spectrally similar iron-bearing oxide...

  8. Globalization

    OpenAIRE

    Andru?cã Maria Carmen

    2013-01-01

    The field of globalization has highlighted an interdependence implied by a more harmonious understanding determined by the daily interaction between nations through the inducement of peace and the management of streamlining and the effectiveness of the global economy. For the functioning of the globalization, the developing countries that can be helped by the developed ones must be involved. The international community can contribute to the institution of the development environment of the gl...

  9. New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151

    Science.gov (United States)

    Denes Couto, Jullianna

    2017-08-01

    Active Galactic Nuclei (AGNs) exist in a few percent of all massive galaxies. It is believed that AGNs are powered by accretion of matter onto a supermassive black hole (SMBH), generating in the process huge amounts of radiation that span the entire electromagnetic spectrum. In turn, this also triggers the so-called AGN Feedback phenomenon, by inducing the formation of accretion disk winds (or outflows) that accelerate highly ionized gas outwards and affect the intergalactic medium of the host galaxy, reducing star formation rates and preventing bulge growth. It has been suggested that a dominant component of mass outflows is observable in the X-rays, and there are a limited number of detailed studies of single objects for which the relation between outflows and power of the central engine can be determined directly. The Seyfert 1.5 galaxy NGC 4151 is a great study candidate, given its proximity (14.077 Mpc, z = 0.0033), X-ray brightness and orientation. Over the past decades, it has been the target of many single and multiwavelength observations, and its heavily absorbed X-ray spectrum and complex absorption features have been extensively stud- ied and characterized. I have investigated the relationship between the long term X-ray spectral variability in and its intrinsic absorption, by comparing our 2014 simultaneous ultraviolet/X-Ray observations taken with Hubble Space Telescope Imaging Spectrometer (STIS) Echelle and Chandra High Energy Transmission Grating Spectrometer (HETGS) with archival observations from Chandra, XMM-Newton and Suzaku. The observations were divided into "high" and "low" flux states, with the low states showing strong and unabsorbed extended emission at energies below 2 keV. The X-ray model consists of a broken powerlaw, neutral reflection and two dominant absorption components, a high and a low ionization component, which are present in all epochs. The model fittings suggest that the absorbers are very stable, with the principal changes

  10. Batse/Sax and Batse/RXTE-ASM Joint Spectral Studies of GRBs

    Science.gov (United States)

    Paciesas, William S.

    2002-01-01

    We proposed to make joint spectral analysis of gamma-ray bursts (GRBs) in the BATSE data base that are located within the fields of view of either the BeppoSAX wide field cameras (WFCs) or the RXTE all-sky monitor (ASM). The very broad-band coverage obtained in this way would facilitate various studies of GRB spectra that are difficult to perform with BATSE data alone. Unfortunately, the termination of the CGRO mission in June 2000 was not anticipated at the time of the proposal, and the sample of common events turned out to be smaller than we would have liked.

  11. Spectral studies of 2-pyrazoline derivatives: structural elucidation through single crystal XRD and DFT calculations.

    Science.gov (United States)

    Chinnaraja, D; Rajalakshmi, R; Srinivasan, T; Velmurugan, D; Jayabharathi, J

    2014-04-24

    A series of biologically active N-thiocarbamoyl pyrazoline derivatives have been synthesized using anhydrous potassium carbonate as the catalyst. All the synthesized compounds were characterized by FT-IR, (1)H NMR, (13)C NMR spectral studies, LCMS, CHN Analysis and X-ray diffraction analysis (compound 7). In order to supplement the XRD parameters, molecular modelling was carried out by Gaussian 03W. From the optimized structure, the energy, dipolemoment and HOMO-LUMO energies of all the systems were calculated. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Study of the spectral characteristics of unidentified galactic EGRET sources. Are they pulsar-like?

    Science.gov (United States)

    Merck, M.; Bertsch, D. L.; Dingus, B. L.; Esposito, J. A.; Fichtel, C. E.; Fierro, J. M.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.; Kniffen, D. A.; Lin, Y. C.; Mayer-Hasselwander, H. A.; Michelson, P. F.; von Montigny, C.; Muecke, A.; Mukherjee, R.; Nolan, P. L.; Pohl, M.; Schneid, E.; Sreekumar, P.; Thompson, D. J.; Willis, T. D.

    1996-12-01

    A spectral study of unidentified galactic EGRET sources was performed. The derived spectra are compared to the spectra of pulsars to test the hypothesis, that a significant fraction of these sources are Geminga like radio-quiet pulsars (Yadigaroglu & Romani 1995ApJ...449..211Y). Most of the sources show significantly different spectra than expected under this hypothesis. Of those with spectra consistent with typical pulsar spectra, four are positionally consistent with young spin-powered radio pulsars leaving only very few Geminga type candidates in the sample.

  13. The Global People landscaping study: intercultural effectiveness in global education partnerships

    OpenAIRE

    Reid, S.; Stadler, Stefanie; Spencer-Oatey, Helen

    2009-01-01

    The Context\\ud The Higher Education sector in the UK is experiencing a period of rapid and competitive internationalisation. The market for higher education, at undergraduate and post graduate levels, is now truly global: many potential students can make choices about study destinations between an enormous range of institutions in any of the five continents. The audience for research is also global, with a proliferation of domestic and international journals, a multitude of international conf...

  14. Quantitative contrast-enhanced spectral mammography based on photon-counting detectors: A feasibility study.

    Science.gov (United States)

    Ding, Huanjun; Molloi, Sabee

    2017-08-01

    To investigate the feasibility of accurate quantification of iodine mass thickness in contrast-enhanced spectral mammography. A computer simulation model was developed to evaluate the performance of a photon-counting spectral mammography system in the application of contrast-enhanced spectral mammography. A figure-of-merit (FOM), which was defined as the decomposed iodine signal-to-noise ratio (SNR) with respect to the square root of the mean glandular dose (MGD), was chosen to optimize the imaging parameters, in terms of beam energy, splitting energy, and prefiltrations for breasts of various thicknesses and densities. Experimental phantom studies were also performed using a beam energy of 40 kVp and a splitting energy of 34 keV with 3 mm Al prefiltration. A two-step calibration method was investigated to quantify the iodine mass thickness, and was validated using phantoms composed of a mixture of glandular and adipose materials, for various breast thicknesses and densities. Finally, the traditional dual-energy log-weighted subtraction method was also studied as a comparison. The measured iodine signal from both methods was compared to the known value to characterize the quantification accuracy and precision. The optimal imaging parameters, which lead to the highest FOM, were found at a beam energy between 42 and 46 kVp with a splitting energy at 34 keV. The optimal tube voltage decreased as the breast thickness or the Al prefiltration increased. The proposed quantification method was able to measure iodine mass thickness on phantoms of various thicknesses and densities with high accuracy. The root-mean-square (RMS) error for cm-scale lesion phantoms was estimated to be 0.20 mg/cm 2 . The precision of the technique, characterized by the standard deviation of the measurements, was estimated to be 0.18 mg/cm 2 . The traditional weighted subtraction method also predicted a linear correlation between the measured signal and the known iodine mass thickness. However

  15. Feasibility study of a novel miniaturized spectral imaging system architecture in UAV surveillance

    Science.gov (United States)

    Liu, Shuyang; Zhou, Tao; Jia, Xiaodong; Cui, Hushan; Huang, Chengjun

    2016-01-01

    The spectral imaging technology is able to analysis the spectral and spatial geometric character of the target at the same time. To break through the limitation brought by the size, weight and cost of the traditional spectral imaging instrument, a miniaturized novel spectral imaging based on CMOS processing has been introduced in the market. This technology has enabled the possibility of applying spectral imaging in the UAV platform. In this paper, the relevant technology and the related possible applications have been presented to implement a quick, flexible and more detailed remote sensing system.

  16. Low-Dose Contrast-Enhanced Breast CT Using Spectral Shaping Filters: An Experimental Study.

    Science.gov (United States)

    Makeev, Andrey; Glick, Stephen J

    2017-12-01

    Iodinated contrast-enhanced X-ray imaging of the breast has been studied with various modalities, including full-field digital mammography (FFDM), digital breast tomosynthesis (DBT), and dedicated breast CT. Contrast imaging with breast CT has a number of advantages over FFDM and DBT, including the lack of breast compression, and generation of fully isotropic 3-D reconstructions. Nonetheless, for breast CT to be considered as a viable tool for routine clinical use, it would be desirable to reduce radiation dose. One approach for dose reduction in breast CT is spectral shaping using X-ray filters. In this paper, two high atomic number filter materials are studied, namely, gadolinium (Gd) and erbium (Er), and compared with Al and Cu filters currently used in breast CT systems. Task-based performance is assessed by imaging a cylindrical poly(methyl methacrylate) phantom with iodine inserts on a benchtop breast CT system that emulates clinical breast CT. To evaluate detectability, a channelized hoteling observer (CHO) is used with sums of Laguerre-Gauss channels. It was observed that spectral shaping using Er and Gd filters substantially increased the dose efficiency (defined as signal-to-noise ratio of the CHO divided by mean glandular dose) as compared with kilovolt peak and filter settings used in commercial and prototype breast CT systems. These experimental phantom study results are encouraging for reducing dose of breast CT, however, further evaluation involving patients is needed.

  17. Studying the Impacts of Globalization on Iranian Education System

    Science.gov (United States)

    Chahardahcheriki, Mitra Abdolahi; Shahi, Sakine

    2012-01-01

    The purpose of this study is to analyze the degree of globalization of important indicators of education system in Iran including teaching approaches, educational tools and facilities, curriculums and contents, and education management. Findings suggest that the situation of Iranian education system has some distance with the globalized level and…

  18. College of Business Majors' Perceptions toward Globalization: An Empirical Study

    Science.gov (United States)

    Janavaras, Basil; Kuzma, John; Thiewes, Harold

    2008-01-01

    The objective of this paper is to determine the extent to which business majors' attitudes towards globalization are influenced by the area of selected study. Research has documented that more favorable attitudes towards globalization are found among college students, and specifically, these more favorable attitudes are found in business majors.…

  19. Broad-band spectral studies of optical lightnings and possible correlation with solar activity

    International Nuclear Information System (INIS)

    Bhat, C.L.; Sapru, M.L.; Kaul, R.K.; Razdan, H.

    1984-01-01

    Optical pulses from lightning discharges have been recorded in a ground-based experiment, meant primarily for the detection of cosmic X- and γ-ray bursts through the atmospheric fluorescence technique. It is shown that the spectral ratio Asub(v)/Asub(y), i.e. the ratio of pulse amplitudes in the violet to that in yellow wavelength bands (3400-4300 A and 4400-6000 A respectively) provides a good indication of the lightning channel temperature, the range of derived temperatures extending from 5.000 K to 60.000 K. Based on the distribution of observed Asub(v)/Asub(y) values on a daily basis, it has been possible to separate the observed lightning activity into two classes. One class of event is shown to be correlated with the peaking of the global atmospheric electric field and occurs preferentially on days when the ground-level cosmic ray intensity shows a significant decrease in association with an increase in geomagnetic activity. The results are discussed in terms of the contemporary views regarding solar control of atmospheric electricity and the various sun-weather correlations reported earlier. (author)

  20. A Comparative Study of Spectral Auroral Intensity Predictions From Multiple Electron Transport Models

    Science.gov (United States)

    Grubbs, Guy; Michell, Robert; Samara, Marilia; Hampton, Donald; Hecht, James; Solomon, Stanley; Jahn, Jorg-Micha

    2018-01-01

    It is important to routinely examine and update models used to predict auroral emissions resulting from precipitating electrons in Earth's magnetotail. These models are commonly used to invert spectral auroral ground-based images to infer characteristics about incident electron populations when in situ measurements are unavailable. In this work, we examine and compare auroral emission intensities predicted by three commonly used electron transport models using varying electron population characteristics. We then compare model predictions to same-volume in situ electron measurements and ground-based imaging to qualitatively examine modeling prediction error. Initial comparisons showed differences in predictions by the GLobal airglOW (GLOW) model and the other transport models examined. Chemical reaction rates and radiative rates in GLOW were updated using recent publications, and predictions showed better agreement with the other models and the same-volume data, stressing that these rates are important to consider when modeling auroral processes. Predictions by each model exhibit similar behavior for varying atmospheric constants, energies, and energy fluxes. Same-volume electron data and images are highly correlated with predictions by each model, showing that these models can be used to accurately derive electron characteristics and ionospheric parameters based solely on multispectral optical imaging data.

  1. Synthesis, XRD, TEM, EPR, and Optical Absorption Spectral Studies of CuZnO2 Nanocompound

    Directory of Open Access Journals (Sweden)

    T. Ravindra Reddy

    2014-01-01

    Full Text Available Synthesis of nano CuZnO2 compound is carried out by thermal decomposition method. The crystalline phase of the material is characterized by XRD. The calculated unit cell constants are a=3.1 Å and c=3.4786 Å and are of tetragonal structure. The unit cell constants are different from wurtzite (hexagonal which indicate that a nanocompound is formed. Further TEM images reveal that the metal ion is in tetragonal structure with oxygen ligands. The prepared CuZnO2 is then characterized for crystallite size analysis by employing transmission electron microscopy (TEM. The size is found to be 100 nm. Uniform bright rings are noticed in the TEM picture suggesting that the nanocrystals have preferential instead of random orientations. The selected-area electron diffraction (SAED pattern clearly indicates the formation of CuO-ZnO nanocompound. The nature of bonding is studied by electron paramagnetic resonance (EPR. The covalency character is about 0.74 and thus the compound is electrically less conductive. Optical absorption spectral studies suggest that Cu(II is placed in tetragonal elongation crystal field. The spin-orbit coupling constant, λ, is calculated using the EPR and optical absorption spectral results suggest some covalent bond between metal and ligand. Near infrared (NIR spectra are due to hydroxyl and water fundamentals.

  2. SARAS 2: a spectral radiometer for probing cosmic dawn and the epoch of reionization through detection of the global 21-cm signal

    Science.gov (United States)

    Singh, Saurabh; Subrahmanyan, Ravi; Shankar, N. Udaya; Rao, Mayuri Sathyanarayana; Girish, B. S.; Raghunathan, A.; Somashekar, R.; Srivani, K. S.

    2018-04-01

    The global 21-cm signal from Cosmic Dawn (CD) and the Epoch of Reionization (EoR), at redshifts z ˜ 6-30, probes the nature of first sources of radiation as well as physics of the Inter-Galactic Medium (IGM). Given that the signal is predicted to be extremely weak, of wide fractional bandwidth, and lies in a frequency range that is dominated by Galactic and Extragalactic foregrounds as well as Radio Frequency Interference, detection of the signal is a daunting task. Critical to the experiment is the manner in which the sky signal is represented through the instrument. It is of utmost importance to design a system whose spectral bandpass and additive spurious signals can be well calibrated and any calibration residual does not mimic the signal. Shaped Antenna measurement of the background RAdio Spectrum (SARAS) is an ongoing experiment that aims to detect the global 21-cm signal. Here we present the design philosophy of the SARAS 2 system and discuss its performance and limitations based on laboratory and field measurements. Laboratory tests with the antenna replaced with a variety of terminations, including a network model for the antenna impedance, show that the gain calibration and modeling of internal additive signals leave no residuals with Fourier amplitudes exceeding 2 mK, or residual Gaussians of 25 MHz width with amplitudes exceeding 2 mK. Thus, even accounting for reflection and radiation efficiency losses in the antenna, the SARAS 2 system is capable of detection of complex 21-cm profiles at the level predicted by currently favoured models for thermal baryon evolution.

  3. The Nature of Global Large-scale Sea Level Variability in Relation to Atmospheric Forcing: A Modeling Study

    Science.gov (United States)

    Fukumori, I.; Raghunath, R.; Fu, L. L.

    1996-01-01

    The relation between large-scale sea level variability and ocean circulation is studied using a numerical model. A global primitive equaiton model of the ocean is forced by daily winds and climatological heat fluxes corresponding to the period from January 1992 to February 1996. The physical nature of the temporal variability from periods of days to a year, are examined based on spectral analyses of model results and comparisons with satellite altimetry and tide gauge measurements.

  4. Study on the effects of sample selection on spectral reflectance reconstruction based on the algorithm of compressive sensing

    International Nuclear Information System (INIS)

    Zhang, Leihong; Liang, Dong

    2016-01-01

    In order to solve the problem that reconstruction efficiency and precision is not high, in this paper different samples are selected to reconstruct spectral reflectance, and a new kind of spectral reflectance reconstruction method based on the algorithm of compressive sensing is provided. Four different color numbers of matte color cards such as the ColorChecker Color Rendition Chart and Color Checker SG, the copperplate paper spot color card of Panton, and the Munsell colors card are chosen as training samples, the spectral image is reconstructed respectively by the algorithm of compressive sensing and pseudo-inverse and Wiener, and the results are compared. These methods of spectral reconstruction are evaluated by root mean square error and color difference accuracy. The experiments show that the cumulative contribution rate and color difference of the Munsell colors card are better than those of the other three numbers of color cards in the same conditions of reconstruction, and the accuracy of the spectral reconstruction will be affected by the training sample of different numbers of color cards. The key technology of reconstruction means that the uniformity and representation of the training sample selection has important significance upon reconstruction. In this paper, the influence of the sample selection on the spectral image reconstruction is studied. The precision of the spectral reconstruction based on the algorithm of compressive sensing is higher than that of the traditional algorithm of spectral reconstruction. By the MATLAB simulation results, it can be seen that the spectral reconstruction precision and efficiency are affected by the different color numbers of the training sample. (paper)

  5. Pre-physical treatment: an important procedure to improve spectral resolution in polymers microstructure studies using 13C solution NMR

    International Nuclear Information System (INIS)

    Pedroza, Oscar J.O.; Tavares, Maria I.B.

    2004-01-01

    Changes in physical properties of polymeric materials can be evaluated from their microstructures, which can be investigated using solution carbon-13 nuclear magnetic resonance (NMR). In this type of study spectral resolution is very important, which obviously depend on the sample and solvent. A pre physical treatment allows for an improvement in the spectral resolution. Consequently, more information on chain linking can be obtained, thus facilitating the determination of the stereo sequences. (author)

  6. Spectrally shaped broadband study of up-conversion in Y2O3:Er3+

    International Nuclear Information System (INIS)

    Lytle, A.L.; Gagnon, E.; Tulchinsky, L.; Krebs, J.K.

    2014-01-01

    We present a novel scheme for studying up-conversion through excited state absorption (ESA) by using a broadband excitation source with spectral shaping capabilities. Up-conversion processes have typically been investigated using a single, narrowband excitation source, when the two steps of the process are coincident in frequency, which is often made possible by broadening mechanisms of the intermediate excited state manifolds. Thus, narrowband sources are limited in the systems they can excite and what material information they can provide. With broadband light, we are able to drive up-conversion with non-coincident frequencies as well. Finally, by windowing the spectrum, we determine the optimal excitation bandwidth for low-concentration (1%) Y 2 O 3 :Er 3+ nanocrystals. - Highlights: • Broadband excitation light is used to drive up-conversion in Y 2 O 3 :Er 3+ . • Broadband light excites all available transitions in the two-photon process. • A spectral shaping technique is used to alter the excitation frequencies present. • The optimal excitation bandwidth is measured by windowing the spectrum. • Broadband excitation reveals information inaccessible by narrowband sources

  7. [Study on expert system of infrared spectral characteristic of combustible smoke agent].

    Science.gov (United States)

    Song, Dong-ming; Guan, Hua; Hou, Wei; Pan, Gong-pei

    2009-05-01

    The present paper studied the application of expert system in prediction of infrared spectral characteristic of combustible anti-infrared smoke agent. The construction of the expert system was founded, based on the theory of minimum free energy and infrared spectral addition. After the direction of smoke agent was input, the expert system could figure out the final combustion products. Then infrared spectrogram of smoke could also be simulated by adding the spectra of all of the combustion products. Meanwhile, the screening index of smoke was provided in the wave bands of 3-5 im and 8-14 microm. FTIR spectroscope was used to investigate the performance of one kind of HC smoke. The combustion products calculated by the expert system were coincident with the actual data, and the simulant infrared spectrum was also similar to the real one of the smoke. The screening index given by the system was consistent with the known facts. It was showed that a new approach was offered for the fast discrimination of varieties of directions of smoke agent.

  8. High spectral resolution studies of gamma ray bursts on new missions

    International Nuclear Information System (INIS)

    Desai, U. D.; Acuna, M. H.; Cline, T. L.; Dennis, B. R.; Orwig, L. E.; Trombka, J. I.; Starr, R. D.

    1996-01-01

    Two new missions will be launched in 1996 and 1997, each carrying X-ray and gamma ray detectors capable of high spectral resolution at room temperature. The Argentine Satelite de Aplicaciones Cientificas (SAC-B) and the Small Spacecraft Technology Initiative (SSTI) Clark missions will each carry several arrays of X-ray detectors primarily intended for the study of solar flares and gamma-ray bursts. Arrays of small (1 cm 2 ) cadmium zinc telluride (CZT) units will provide x-ray measurements in the 10 to 80 keV range with an energy resolution of ≅6 keV. Arrays of both silicon avalanche photodiodes (APD) and P-intrinsic-N (PIN) photodiodes (for the SAC-B mission only) will provide energy coverage from 2-25 keV with ≅1 keV resolution. For SAC-B, higher energy spectral data covering the 30-300 keV energy range will be provided by CsI(Tl) scintillators coupled to silicon APDs, resulting in similar resolution but greater simplicity relative to conventional CsI/PMT systems. Because of problems with the Pegasus launch vehicle, the launch of SAC-B has been delayed until 1997. The launch of the SSTI Clark mission is scheduled for June 1996

  9. Local and global statistical dynamical properties of chaotic Markov analytic maps and repellers: A coarse grained and spectral perspective

    International Nuclear Information System (INIS)

    MacKernan, Donal; Basios, Vasileios

    2009-01-01

    The statistical properties of chaotic Markov analytic maps and equivalent repellers are investigated through matrix representations of the Frobenius-Perron operator (U). The associated basis sets are constructed using Chebyshev functions and Markov partitions which can be tailored to examine statistical dynamical properties associated with observables having support over local regions or for example, about periodic orbits. The decay properties of corresponding time correlations functions are given by a analytic expression of the spectra of U which is expected to be valid for a much larger class of systems than that studied here. An explicit and general expression is also derived for the correction factor to the dynamical zeta functions occurring when analytic function spaces are not invariant under U.

  10. Studying the complex spectral line profiles in the spectra of hot emission stars and quasars .

    Science.gov (United States)

    Danezis, E.; Lyratzi, E.; Antoniou, A.; Popović, L. Č.; Dimitrijević, M. S.

    Some Hot Emission Stars and AGNs present peculiar spectral line profiles which are due to DACs and SACs phenomena. The origin and the mechanisms which are responsible for the creation of DACs/SACs is an important problem that has been studied by many researchers. This paper is a review of our efforts to study the origin and the mechanisms of these phenomena. At first we present a theoretic ad hoc picture for the structure of the plasma that surrounds the specific category of hot emission stars that present DACs or SACs. Then we present the mathematical model that we constructed, which is based on the properties of the above ad hoc theoretical structure. Finally, we present some results from our statistical studies that prove the consistency of our model with the classical physical theory.

  11. Globalization

    DEFF Research Database (Denmark)

    Plum, Maja

    Globalization is often referred to as external to education - a state of affair facing the modern curriculum with numerous challenges. In this paper it is examined as internal to curriculum; analysed as a problematization in a Foucaultian sense. That is, as a complex of attentions, worries, ways...... of reasoning, producing curricular variables. The analysis is made through an example of early childhood curriculum in Danish Pre-school, and the way the curricular variable of the pre-school child comes into being through globalization as a problematization, carried forth by the comparative practices of PISA...

  12. Globalization

    OpenAIRE

    F. Gerard Adams

    2008-01-01

    The rapid globalization of the world economy is causing fundamental changes in patterns of trade and finance. Some economists have argued that globalization has arrived and that the world is “flat†. While the geographic scope of markets has increased, the author argues that new patterns of trade and finance are a result of the discrepancies between “old†countries and “new†. As the differences are gradually wiped out, particularly if knowledge and technology spread worldwide, the t...

  13. Global noise studies for CMS Tracker upgrade

    CERN Document Server

    Arteche, F; Echevarria, I; Iglesias, M; Rivetta, C; Vila, I; 10.1088/1748-0221/5/12/C12029

    2010-01-01

    The characterization of the noise emissions of DC-DC converters at system level is critical to optimize the design of the detector and define rules for the integration strategy. This paper presents the impedance effects on the noise emissions of DC-DC converters at system level. Conducted and radiated noise emissions at the input and at the output from DC-DC converters have been simulated for different types of power network and FEE impedances. System aspects as granularity, stray capacitances of the system and different working conditions of the DC-DC converters are presented too. This study has been carried out using simulation models of noise emissions of DC-DC converters in the real scenario. The results of these studies show important recommendations and criteria to be applied to integrate the DC-DC converters and decrease the system noise level

  14. Ultrasonic wave propagation in viscoelastic cortical bone plate coupled with fluids: a spectral finite element study.

    Science.gov (United States)

    Nguyen, Vu-Hieu; Naili, Salah

    2013-01-01

    This work deals with the ultrasonic wave propagation in the cortical layer of long bones which is known as being a functionally graded anisotropic material coupled with fluids. The viscous effects are taken into account. The geometrical configuration mimics the one of axial transmission technique used for evaluating the bone quality. We present a numerical procedure adapted for this purpose which is based on the spectral finite element method (FEM). By using a combined Laplace-Fourier transform, the vibroacoustic problem may be transformed into the frequency-wavenumber domain in which, as radiation conditions may be exactly introduced in the infinite fluid halfspaces, only the heterogeneous solid layer needs to be analysed using FEM. Several numerical tests are presented showing very good performance of the proposed approach. We present some results to study the influence of the frequency on the first arriving signal velocity in (visco)elastic bone plate.

  15. Synthesis, Spectral and Anthelmintic Activity Studies on Some Novel Imidazole Derivatives

    Directory of Open Access Journals (Sweden)

    Rajiv Dahiya

    2008-01-01

    Full Text Available Present study describes the synthesis of a novel series of 3,5-diiodo-4-(5-nitro-1H-2-imidazolylbenzoyl amino acids and di/tri/tetrapeptides using diisopropylcarbodiimide/dicyclohexylcarbodiimide (DIPC/DCC as coupling agents and N-methylmorpholine/triethylamine (NMM/TEA as bases. Structure elucidation of all the newly synthesized compounds was done by elemental analysis and IR, 1H NMR, 13C NMR and mass spectral data. Synthesized imidazolopeptides were screened for their anthelmintic activity and found to possess moderate to good bioactivity against earthworms Megascoplex konkanensis, Pontoscotex corethruses and Eudrilus eugeniea when compared to reference drugs - albendazole and mebendazole at dose level of 2 mg mL−1.

  16. Study of $\\tau$ decays involving kaons, spectral functions and determination of the strange quark mass

    CERN Document Server

    Barate, R.; Ghez, Philippe; Goy, C.; Lees, J.P.; Merle, E.; Minard, M.N.; Pietrzyk, B.; Alemany, R.; Casado, M.P.; Chmeissani, M.; Crespo, J.M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Grauges, E.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, L.M.; Pacheco, A.; Park, I.C.; Riu, I.; Colaleo, A.; Creanza, D.; De Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Becker, U.; Boix, G.; Cattaneo, M.; Ciulli, V.; Dissertori, G.; Drevermann, H.; Forty, R.W.; Frank, M.; Halley, A.W.; Hansen, J.B.; Harvey, John; Janot, P.; Jost, B.; Lehraus, I.; Leroy, O.; Mato, P.; Minten, A.; Moutoussi, A.; Ranjard, F.; Rolandi, Gigi; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Teubert, F.; Tomalin, I.R.; Tournefier, E.; Wright, A.E.; Ajaltouni, Z.; Badaud, F.; Chazelle, G.; Deschamps, O.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.C.; Pallin, D.; Perret, P.; Podlyski, F.; Hansen, J.D.; Hansen, J.R.; Hansen, P.H.; Nilsson, B.S.; Rensch, B.; Waananen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J.C.; Rouge, A.; Rumpf, M.; Swynghedauw, M.; Verderi, M.; Videau, H.; Focardi, E.; Parrini, G.; Zachariadou, K.; Cavanaugh, R.; Corden, M.; Georgiopoulos, C.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G.P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Lynch, J.G.; Negus, P.; O'Shea, V.; Raine, C.; Teixeira-Dias, P.; Thompson, A.S.; Buchmuller, O.; Dhamotharan, S.; Geweniger, C.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E.E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D.M.; Cameron, W.; Dornan, P.J.; Girone, M.; Goodsir, S.; Martin, E.B.; Marinelli, N.; Sedgbeer, J.K.; Spagnolo, P.; Thomson, Evelyn J.; Williams, M.D.; Ghete, V.M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Betteridge, A.P.; Bowdery, C.K.; Buck, P.G.; Colrain, P.; Crawford, G.; Finch, A.J.; Foster, F.; Hughes, G.; Jones, R.W.L.; Robertson, N.A.; Williams, M.I.; Giehl, I.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.G.; van Gemmeren, P.; Wachsmuth, H.; Zeitnitz, C.; Aubert, J.J.; Benchouk, C.; Bonissent, A.; Carr, J.; Coyle, P.; Etienne, F.; Motsch, F.; Payre, P.; Talby, M.; Thulasidas, M.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Berlich, R.; Buescher, Volker; Dietl, H.; Ganis, G.; Huttmann, K.; Lutjens, G.; Mannert, C.; Manner, W.; Moser, H.G.; Schael, S.; Settles, R.; Seywerd, H.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Azzurri, P.; Boucrot, J.; Callot, O.; Chen, S.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.F.; Heusse, P.; Hocker, Andreas; Jacholkowska, A.; Kim, D.W.; Le Diberder, F.; Lefrancois, J.; Lutz, A.M.; Schune, M.H.; Veillet, J.J.; Videau, I.; Zerwas, D.; Bagliesi, Giuseppe; Bettarini, S.; Boccali, T.; Bozzi, C.; Calderini, G.; Dell'Orso, R.; Ferrante, I.; Foa, L.; Giassi, A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P.S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sciaba, A.; Sguazzoni, G.; Tenchini, R.; Vannini, C.; Venturi, A.; Verdini, P.G.; Blair, G.A.; Cowan, G.; Green, M.G.; Medcalf, T.; Strong, J.A.; von Wimmersperg-Toeller, J.H.; Botterill, D.R.; Clifft, R.W.; Edgecock, T.R.; Norton, P.R.; Thompson, J.C.; Bloch-Devaux, Brigitte; Colas, P.; Emery, S.; Kozanecki, W.; Lancon, E.; Lemaire, M.C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.F.; Roussarie, A.; Schuller, J.P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S.N.; Dann, J.H.; Johnson, R.P.; Kim, H.Y.; Konstantinidis, N.; Litke, A.M.; McNeil, M.A.; Taylor, G.; Booth, C.N.; Cartwright, S.; Combley, F.; Kelly, M.S.; Lehto, M.; Thompson, L.F.; Affholderbach, K.; Boehrer, Armin; Brandt, S.; Grupen, C.; Prange, G.; Giannini, G.; Gobbo, B.; Rothberg, J.; Wasserbaech, S.; Armstrong, S.R.; Charles, E.; Elmer, P.; Ferguson, D.P.S.; Gao, Y.; Gonzalez, S.; Greening, T.C.; Hayes, O.J.; Hu, H.; Jin, S.; McNamara, P.A., III; Nachtman, J.M.; Nielsen, J.; Orejudos, W.; Pan, Y.B.; Saadi, Y.; Scott, I.J.; Walsh, J.; Wu, Sau Lan; Wu, X.; Zobernig, G.

    1999-01-01

    All ALEPH measurements of branching ratios of tau decays involving kaons are summarized including a combination of results obtained with K^0_S and K^0_L detection. The decay dynamics are studied, leading to the determination of contributions from vector K^*(892) and K^{*}(1410), and axial-vector K_1(1270) and K_1(1400) resonances. Agreement with isospin symmetry is observed among the different final states. Under the hypothesis of the conserved vector current, the spectral function for the K\\bar{K}\\pi mode is compared with the corresponding cross section for low energy e^+e^- annihilation, yielding an axial-vector fraction of (94^{+6}_{-8})% for this mode. The branching ratio for tau decay into all strange final states is determined to be B(\\tau^-\\to X^-(S=-1)\

  17. Synthesis, Spectral and Antimicrobial Studies of Some N(2)-Substituted Tetrahydroindazoles

    International Nuclear Information System (INIS)

    Amirthaganesan, Shanmugasundaram; Aridoss, Gopalakrishnan; Park, Keun Soo; Lim, Kwon Taek; Jeong, Yeon Tae

    2010-01-01

    A series of N(2)-benzothiazolyl substituted tetrahydroindazoles has been synthesized via cyclic β keto esters. Optimum reaction condition was found as acidic toluene and effect of higher acidity towards substituted hydrazines in situ was described. Synthesized compounds have been achieved as single isomer and characterized by using 1D and 2D NMR spectral reports. Antimicrobial screening was carried out for the synthesized compounds along with a series of N(2)-pyridyl tetrahydroindazoles. 1 The results of the in vitro antimicrobial screening studies revealed that compounds 13, 16 against Staphylococcus aureus, 11 against Escherichia coli, 10-12, 16 against Pseudomonas aeruginosa and 12 against Klebsiella pneumoniae recorded almost two-fold better activity compared to the standard drug used

  18. Spectral Kernel Approach to Study Radiative Response of Climate Variables and Interannual Variability of Reflected Solar Spectrum

    Science.gov (United States)

    Jin, Zhonghai; Wielicki, Bruce A.; Loukachine, Constantin; Charlock, Thomas P.; Young, David; Noeel, Stefan

    2011-01-01

    The radiative kernel approach provides a simple way to separate the radiative response to different climate parameters and to decompose the feedback into radiative and climate response components. Using CERES/MODIS/Geostationary data, we calculated and analyzed the solar spectral reflectance kernels for various climate parameters on zonal, regional, and global spatial scales. The kernel linearity is tested. Errors in the kernel due to nonlinearity can vary strongly depending on climate parameter, wavelength, surface, and solar elevation; they are large in some absorption bands for some parameters but are negligible in most conditions. The spectral kernels are used to calculate the radiative responses to different climate parameter changes in different latitudes. The results show that the radiative response in high latitudes is sensitive to the coverage of snow and sea ice. The radiative response in low latitudes is contributed mainly by cloud property changes, especially cloud fraction and optical depth. The large cloud height effect is confined to absorption bands, while the cloud particle size effect is found mainly in the near infrared. The kernel approach, which is based on calculations using CERES retrievals, is then tested by direct comparison with spectral measurements from Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) (a different instrument on a different spacecraft). The monthly mean interannual variability of spectral reflectance based on the kernel technique is consistent with satellite observations over the ocean, but not over land, where both model and data have large uncertainty. RMS errors in kernel ]derived monthly global mean reflectance over the ocean compared to observations are about 0.001, and the sampling error is likely a major component.

  19. Global study of quadrupole correlation effects

    International Nuclear Information System (INIS)

    Bender, M.; Bertsch, G.F.; Heenen, P.-H.

    2006-01-01

    We discuss the systematics of ground-state quadrupole correlations of binding energies and mean-square charge radii for all even-even nuclei, from 16 O up to the superheavies, for which data are available. To that aim we calculate their correlated J=0 ground state by means of the angular-momentum and particle-number projected generator coordinate method, using the axial mass quadrupole moment as the generator coordinate and self-consistent mean-field states restricted only by axial, parity, and time-reversal symmetries. The calculation is performed within the framework of a nonrelativistic self-consistent mean-field model by use of the same Skyrme interaction SLy4 and to a density-dependent pairing force to generate the mean-field configurations and to mix them. These are the main conclusions of our study: (i) The quadrupole correlation energy varies between a few 100 keV and about 5.5 MeV. It is affected by shell closures, but varies only slightly with mass and asymmetry. (ii) Projection on angular momentum J=0 provides the major part of the energy gain of up to about 4 MeV; all nuclei in the study, including doubly magic ones, gain energy by deformation. (iii) The mixing of projected states with different intrinsic axial deformations adds a few 100 keV up to 1.5 MeV to the correlation energy. (iv) Typically nuclei below mass A≤60 have a larger correlation energy than static deformation energy whereas the heavier deformed nuclei have larger static deformation energy than correlation energy. (v) Inclusion of the quadrupole correlation energy improves the description of mass systematics, particularly around shell closures, and of differential quantities, namely two-nucleon separation energies and two-nucleon gaps. The correlation energy provides an explanation of 'mutually enhanced magicity'. (vi) The correlation energy tends to decrease the shell effect on binding energies around magic numbers, but the magnitude of the suppression is not large enough to explain

  20. An inter-hemispheric, statistical study of nightside spectral width distributions from coherent HF scatter radars

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    2002-12-01

    Full Text Available A statistical investigation of the Doppler spectral width parameter routinely observed by HF coherent radars has been conducted between the Northern and Southern Hemispheres for the nightside ionosphere. Data from the SuperDARN radars at Thykkvibær, Iceland and Syowa East, Antarctica have been employed for this purpose. Both radars frequently observe regions of high (>200 ms-1 spectral width polewards of low (<200 ms-1 spectral width. Three years of data from both radars have been analysed both for the spectral width and line of sight velocity. The pointing direction of these two radars is such that the flow reversal boundary may be estimated from the velocity data, and therefore, we have an estimate of the open/closed field line boundary location for comparison with the high spectral widths. Five key observations regarding the behaviour of the spectral width on the nightside have been made. These are (i the two radars observe similar characteristics on a statistical basis; (ii a latitudinal dependence related to magnetic local time is found in both hemispheres; (iii a seasonal dependence of the spectral width is observed by both radars, which shows a marked absence of latitudinal dependence during the summer months; (iv in general, the Syowa East spectral width tends to be larger than that from Iceland East, and (v the highest spectral widths seem to appear on both open and closed field lines. Points (i and (ii indicate that the cause of high spectral width is magnetospheric in origin. Point (iii suggests that either the propagation of the HF radio waves to regions of high spectral width or the generating mechanism(s for high spectral width is affected by solar illumination or other seasonal effects. Point (iv suggests that the radar beams from each of the radars are subject either to different instrumental or propagation effects, or different geophysical conditions due to their locations, although we suggest that this result is more likely to

  1. Study Behaviour: A counselling approach | Okpechi | Global Journal ...

    African Journals Online (AJOL)

    The researcher recommended that students should take their studies seriously as their failure and success lies on it. He equally draws the attention of students to the essentials of study behaviour, time management, organisation of study task, etc. Global Journal of Educational Research Vol. 5 (1&2) 2006: pp. 5-11 ...

  2. Study of the spectral bandwidth of a double-pass acousto-optic system [Invited].

    Science.gov (United States)

    Champagne, Justine; Kastelik, Jean-Claude; Dupont, Samuel; Gazalet, Joseph

    2018-04-01

    Acousto-optic tunable filters are known as efficient instruments for spectral and spatial filtering of light. In this paper, we analyze the bandwidth dependence of a double-pass filter. The interaction geometry chosen allows the simultaneous diffraction of the ordinary and the extraordinary optical modes by a single ultrasonic frequency. We present the main parameters of a custom device (design, optical range, driving frequency) and experimental results concerning the angular deviation of the beams including the effect of optical birefringence. The spectral resolution and the side lobes' significance are discussed. Spectral bandwidth of such a system is analyzed.

  3. Globalized mobility and the loss of the collective? Refugees and global palyers: An ethnopsychoanlaytical study

    Directory of Open Access Journals (Sweden)

    Ernestine Wohlfart

    2014-09-01

    Full Text Available The essay sheds a light on mobile individuals, the motivation behind their movement, and their experience in foreign social contexts. It is based on group analytical and interdisciplinary discourses. The focus lies on possible changings of the collective in globalized worlds- approached by the view of individuals. What could imply the loss of the primary group and the perception of this loss for the individual. What are the mobile individuals (refugees and global players looking to find abroad, what are the promises, the demands and necessities. Material: I am offering for discussion texts from an ethnopsychoanalytical study focusing on two very different groups of mobile individuals. On one hand, interviews with so-called "global players" or "job nomads" and on the other hand interviews with African refugees. The analysis of the material leads to the first hypothesis: The option offered by a globalised world to find an individual place and freedom everywhere in the world is associated with a lack of intersubjective spaces, a lack of embodiment in a group, less sharing of common meanings, rules and taboos.Keywords: Intersubjective space; Mobility; Global players; Refugees

  4. Globalized mobility and the loss of the collective? Refugees and global palyers: An ethnopsychoanlaytical study

    Directory of Open Access Journals (Sweden)

    Ernestine Wohlfart

    2014-09-01

    Full Text Available The essay sheds a light on mobile individuals, the motivation behind their movement, and their experience in foreign social contexts. It is based on group analytical and interdisciplinary discourses. The focus lies on possible changings of the collective in globalized worlds- approached by the view of individuals. What could imply the loss of the primary group and the perception of this loss for the individual. What are the mobile individuals (refugees and global players looking to find abroad, what are the promises, the demands and necessities. Material: I am offering for discussion texts from an ethnopsychoanalytical study focusing on two very different groups of mobile individuals. On one hand, interviews with so-called "global players" or "job nomads" and on the other hand interviews with African refugees. The analysis of the material leads to the first hypothesis: The option offered by a globalised world to find an individual place and freedom everywhere in the world is associated with a lack of intersubjective spaces, a lack of embodiment in a group, less sharing of common meanings, rules and taboos.Keywords: Intersubjective space; Mobility; Global players; Refugees

  5. Enhanced spectral domain optical coherence tomography for pathological and functional studies

    Science.gov (United States)

    Yuan, Zhijia

    Optical coherence tomography (OCT) is a novel technique that enables noninvasive or minimally invasive, cross-sectional imaging of biological tissue at sub-10mum spatial resolution and up to 2-3mm imaging depth. Numerous technological advances have emerged in recent years that have shown great potential to develop OCT into a powerful imaging and diagnostic tools. In particular, the implementation of Fourier-domain OCT (FDOCT) is a major step forward that leads to greatly improved imaging rate and image fidelity of OCT. This dissertation summarizes the work that focuses on enhancing the performances and functionalities of spectral radar based FDOCT (SDOCT) for pathological and functional applications. More specifically, chapters 1-4 emphasize on the development of SDOCT and its utility in pathological studies, including cancer diagnosis. The principle of SDOCT is first briefly outlined, followed by the design of our bench-top SDOCT systems with emphasis on spectral linear interpolation, calibration and system dispersion compensation. For ultrahigh-resolution SDOCT, time-lapse image registration and frame averaging is introduced to effectively reduce speckle noise and uncover subcellular details, showing great promise for enhancing the diagnosis of carcinoma in situ. To overcome the image depth limitation of OCT, a dual-modal imaging method combing SDOCT with high-frequency ultrasound is proposed and examined in animal cancer models to enhance the sensitivity and staging capabilities for bladder cancer diagnosis. Chapters 5-7 summarize the work on developing Doppler SDOCT for functional studies. Digital-frequency-ramping OCT (DFR-OCT) is developed in the study, which has demonstrated the ability to significantly improve the signal-to-noise ratio and thus sensitivity for retrieving subsurface blood flow imaging. New DFR algorithms and imaging processing methods are discussed to further enhance cortical CBF imaging. Applications of DFR-OCT for brain functional studies

  6. Optical characterization of agricultural pest insects: a methodological study in the spectral and time domains

    Science.gov (United States)

    Li, Y. Y.; Zhang, H.; Duan, Z.; Lian, M.; Zhao, G. Y.; Sun, X. H.; Hu, J. D.; Gao, L. N.; Feng, H. Q.; Svanberg, S.

    2016-08-01

    Identification of agricultural pest insects is an important aspect in insect research and agricultural monitoring. We have performed a methodological study of how spectroscopic techniques and wing-beat frequency analysis might provide relevant information. An optical system based on the combination of close-range remote sensing and reflectance spectroscopy was developed to study the optical characteristics of different flying insects, collected in Southern China. The results demonstrate that the combination of wing-beat frequency assessment and reflectance spectral analysis has the potential to successfully differentiate between insect species. Further, studies of spectroscopic characteristics of fixed specimen of insects, also from Central China, showed the possibility of refined agricultural pest identification. Here, in addition to reflectance recordings also laser-induced fluorescence spectra were investigated for all the species of insects under study and found to provide complementary information to optically distinguish insects. In order to prove the practicality of the techniques explored, clearly fieldwork aiming at elucidating the variability of parameters, even within species, must be performed.

  7. SOCl2 catalyzed cyclization of chalcones: Synthesis and spectral studies of some bio-potent 1H pyrazoles

    Directory of Open Access Journals (Sweden)

    K. Ranganathan

    2014-05-01

    Full Text Available Some aryl-aryl 1H pyrazoles have been synthesised by cyclization of aryl chalcones and hydrazine hydrate in the presence of SOCl2. The yields of the pyrazoles are more than 85%. These pyrazoles are characterized by their physical constants and spectral data. The infrared, NMR spectral group frequencies of these pyrazolines have been correlated with Hammett substituent constants, F and R parameters. From the results of statistical analyses the effects of substituent on the spectral frequencies have been studied. The antimicrobial activities of all synthesised pyrazolines have been studied using Bauer-Kirby method. DOI: http://dx.doi.org/10.4314/bcse.v28i2.11

  8. Timing and Spectral Studies of the Peculiar X-ray Binary Circinus X-1

    Energy Technology Data Exchange (ETDEWEB)

    Saz Parkinson, Pablo M.

    2003-08-26

    Circinus X-1 (Cir X-1) is an X-ray binary displaying an array of phenomena which makes it unique in our Galaxy. Despite several decades of observation, controversy surrounds even the most basic facts about this system. It is generally classified as a Neutron Star (NS) Low Mass X-ray Binary (LMXB),though this classification is based primarily on the observation of Type I X-ray Bursts by EXOSAT in 1985. It is believed to be in a very eccentric {approx} 16.5 day orbit, displaying periodic outbursts in the radio and other frequency bands (including optical and IR) which reinforce the notion that this is in fact the orbital period. Cir X-1 lies in the plane of the Galaxy, where optical identification of the companion is made difficult due to dust obscuration. The companion is thought to be a low mass star, though a high mass companion has not currently been ruled out. In this work, the author analyzes recent observations of Cir X-1 made with the Unconventional Stellar Aspect (USA) experiment, as well as archival observations of Cir X-1 made by a variety of instruments, from as early as 1969. The fast (< 1 s) timing properties of Cir X-1 are studied by performing FFT analyses of the USA data. Quasi-Periodic Oscillations (QPOs) in the 1-50 Hz range are found and discussed in the context of recent correlations which question the leading models invoked for their generation. The energy dependence of the QPOs (rms increasing with energy) argues against them being generated in the disk and favors models in which the QPOs are related to a higher energy Comptonizing component. The power spectrum of Cir X-1 in its soft state is compared to that of Cygnus X-1 (Cyg X-1), the prototypical black hole candidate. Using scaling arguments the author argues that the mass of Cir X-1 could exceed significantly the canonical 1.4 M{circle_dot} mass of a neutron star, possibly partly explaining why this object appears so different to other neutron stars. The spectral evolution of Cir X-1 is

  9. Sozial Studies: How Travel Abroad Empowers a Global Perspective

    Science.gov (United States)

    Pearcy, Mark

    2014-01-01

    The personal experiences and values of individual teachers can tend to restrict the ability to promote a "global perspective" in the social studies, the subject area most suited to that concept. One antidote to this instructional myopia is the prospect of overseas travel, in the form of study tours, the type of which have been shown to…

  10. Disability weights for the Global Burden of Disease 2013 study

    NARCIS (Netherlands)

    Salomon, Joshua A.; Haagsma, Juanita A.; Davis, Adrian; de Noordhout, Charline Maertens; Polinder, Suzanne; Havelaar, Arie H.|info:eu-repo/dai/nl/072306122; Cassini, Alessandro; Devleesschauwer, Brecht; Kretzschmar, Mirjam; Speybroeck, Niko; Murray, Christopher J L; Vos, Theo

    2015-01-01

    Background: The Global Burden of Disease (GBD) study assesses health losses from diseases, injuries, and risk factors using disability-adjusted life-years, which need a set of disability weights to quantify health levels associated with non-fatal outcomes. The objective of this study was to estimate

  11. Disability weights for the Global Burden of Disease 2013 study

    NARCIS (Netherlands)

    Salomon, Joshua A; Haagsma, Juanita A; Davis, Adrian; de Noordhout, Charline Maertens; Polinder, Suzanne; Havelaar, Arie H; Cassini, Alessandro; Devleesschauwer, Brecht; Kretzschmar, MEE; Speybroeck, Niko; Murray, Christopher J L; Vos, Theo

    2015-01-01

    BACKGROUND: The Global Burden of Disease (GBD) study assesses health losses from diseases, injuries, and risk factors using disability-adjusted life-years, which need a set of disability weights to quantify health levels associated with non-fatal outcomes. The objective of this study was to estimate

  12. FOREST ECOSYSTEMS AND GLOBAL CHANGE: THE CASE STUDY OF INSUBRIA

    Directory of Open Access Journals (Sweden)

    M. Pautasso

    2013-03-01

    Full Text Available Forest ecosystems face multiple challenges due to climate change, invasive species, urbanization, land use change and the interactions between these global change drivers. This review provides an overview of such challenges for the case study of Insubria. Insubria is a region on the Southern side of the European Alps, famous for its stunning lakes (e.g., Como, Garda, Lugano, Maggiore, blessed by a relatively mild and humid climate, and shaped by the geologic fault line between the African and European plates. Global change impacts in Insubria pose a threat to its biodiversity and chestnut woodlands, particularly through modified winter forest fire regimes. Insubric biodiversity conservation, in turn, is essential to counteract the effects of climate change. Sustainable management of Insubric forests is made more difficult by rural abandonment, air pollution and invasive exotic species. There is a need to develop reliable long-term bio-indicators and to predict the shift of Insubric species, ecosystems and tree-lines due to rapid climate changes. Insubric studies on forests and global change call for enhanced international collaboration in forest management and research. Interdisciplinary approaches are needed to move from studies of single global change drivers to experiments, scenarios and models taking into account their combination and our responses to global change.

  13. Image quality of conventional images of dual-layer SPECTRAL CT: a phantom study.

    Science.gov (United States)

    van Ommen, F; Bennink, E; Vlassenbroek, A; Dankbaar, J W; Schilham, A M R; Viergever, M A; de Jong, H W A M

    2018-05-10

    Spectral CT using a dual layer detector offers the possibility of retrospectively introducing spectral information to conventional CT images. In theory, the dual-layer technology should not come with a dose or image quality penalty for conventional images. In this study, we evaluate the influence of a dual-layer detector (IQon Spectral CT, Philips) on the image quality of conventional CT images, by comparing these images with those of a conventional but otherwise technically comparable single-layer CT scanner (Brilliance iCT, Philips), by means of phantom experiments. For both CT scanners conventional CT images were acquired using four adult scanning protocols: i) body helical, ii) body axial, iii) head helical and iv) head axial. A CATPHAN 600 phantom was scanned to conduct an assessment of image quality metrics at equivalent (CTDI) dose levels. Noise was characterized by means of noise power spectra (NPS) and standard deviation (SD) of a uniform region, and spatial resolution was evaluated with modulation transfer functions (MTF) of a tungsten wire. In addition, contrast-to-noise ratio (CNR), image uniformity, CT number linearity, slice thickness, slice spacing, and spatial linearity were measured and evaluated. Additional measurements of CNR, resolution and noise were performed in two larger phantoms. The resolution levels at 50%, 10% and 5% MTF of the iCT and IQon showed small but significant differences up to 0.25 lp/cm for body scans, and up to 0.2 lp/cm for head scans in favor of the IQon. The iCT and IQon showed perfect CT linearity for body scans, but for head scans both scanners showed an underestimation of the CT numbers of materials with a high opacity. Slice thickness was slightly overestimated for both scanners. Slice spacing was comparable and reconstructed correctly. In addition, spatial linearity was excellent for both scanners, with a maximum error of 0.11 mm. CNR was higher on the IQon compared to the iCT for both normal and larger phantoms with

  14. New 14-membered octaazamacrocyclic complexes of divalent transition metal ions with their antimicrobial and spectral studies

    Science.gov (United States)

    Singh, D. P.; Kumar, Krishan; Sharma, Chetan

    2010-01-01

    A novel series of macrocyclic complexes of the type [M(C 18H 14N 10S 2)X 2]; where M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II); X = Cl -, NO 3-, CH 3COO - has been synthesized by [2+2] condensation of thiocarbohydrazide and isatin in the presence of divalent metal salts in methanolic medium. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic measurements, electronic, NMR and infrared spectral studies. The low value of molar conductance indicates them to be non-electrolytes. On the basis of various studies a distorted octahedral geometry may be proposed for all of these complexes. These metal complexes were also tested for their in vitro antimicrobial activities against some Gram-positive bacteria viz. Staphylococcus aureus, Bacillus subtilis, and some Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa and some fungal strains Aspergillus niger, Aspergillus flavus (molds), Candida albicans, Saccharomyces cerevisiae (yeasts). The results obtained were compared with standard antibiotic: Ciprofloxacin and the standard antifungal drug: Amphotericin-B.

  15. Spectral, thermal, electrochemical and analytical studies on Cd(II) and Hg(II) thiosemicarbazone complexes

    Science.gov (United States)

    El-Asmy, A. A.; El-Gammal, O. A.; Saleh, H. S.

    2008-11-01

    The coordination characteristic of the investigated thiosemicarbazones towards hazard pollutants, Cd(II) and Hg(II), becomes the first goal. Their complexes have been studied by microanalysis, thermal, electrochemical and spectral (electronic, IR and MS) studies. The substitutent (salicylaldehyde, acetophenone, benzophenone, o-hydroxy- p-methoxybenzophenone or diacetylmonoxime) plays an important role in the complex formation. The coordination sites were the S for thiosemicarbazide (HTS); NN for benzophenone thiosemicarbazone (HBTS); NS for acetophenone thiosemicarbazone (HATS) and salicylaldehyde thiosemicarbazone (H 2STS); NNS or NSO for diacetylmonoxime thiosemicarbazone (H 2DMTS). The stability constants of Hg(II) complexes were higher than Cd(II). The kinetic and thermodynamic parameters for the different thermal decomposition steps in the complexes have been evaluated. The activation energy values of the first step ordered the complexes as: [Cd(H 2STS)Cl 2]H 2O > [Cd(H 2DAMTS)Cl 2] > [Cd(HBTS) 2Cl 2]2H 2O > [Cd(HATS) 2Cl 2]. The CV of [Cd(H 2STS)Cl 2]H 2O and [Hg(HBTS)Cl 2] were recorded. The use of H 2DMTS as a new reagent for the separation and determination of Cd(II) ions from water and some synthetic samples using flotation technique is aimed to be discussed.

  16. Multilayer photosensitive structures based on porous silicon and rare-earth-element compounds: Study of spectral characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Kirsanov, N. Yu.; Latukhina, N. V., E-mail: natalat@yandex.ru; Lizunkova, D. A.; Rogozhina, G. A. [Samara National Research University (Russian Federation); Stepikhova, M. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2017-03-15

    The spectral characteristics of the specular reflectance, photosensitivity, and photoluminescence (PL) of multilayer structures based on porous silicon with rare-earth-element (REE) ions are investigated. It is shown that the photosensitivity of these structures in the wavelength range of 0.4–1.0 μm is higher than in structures free of REEs. The structures with Er{sup 3+} ions exhibit a luminescence response at room temperature in the spectral range from 1.1 to 1.7 μm. The PL spectrum of the erbium impurity is characterized by a fine line structure, which is determined by the splitting of the {sup 4}I{sub 15/2} multiplet of the Er{sup 3+} ion. It is shown that the structures with a porous layer on the working surface have a much lower reflectance in the entire spectral range under study (0.2–1.0 μm).

  17. A spectral study of the elementary step of proton transfer in heterogeneous acid catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Kazanskii, V B

    1977-09-01

    A spectral study of the elementary step of proton transfer in heterogeneous acid catalysis involved a determination of the potential curves of the OH bond in surface hydroxyl groups (e.g., those on silica, NaHY zeolite, or glass) of differing acidity from IR stretching frequency data in the overtone region; a calculation of the activation energies for proton transfer during acid catalysis from the changes in the curve forms after adsorption of various molecules (e.g., water, ammonia, benzene, toluene, xylenes, acetone, and cyclohexane); and a comparison of the IR predictions with quantum-chemical calculations of the potential curves. The results appear to furnish a new criterion for the coordinate of reactions involving Broensted sites: if the activation energy measured during actual catalysis is close to that calculated from the IR stretching data, the reaction proceeds by the stepwise mechanism of acid catalysis; but if these values differ greatly, the reaction involves a concerted mechanism (i.e., activation of the adsorbed molecule without involvement of OH groups). Tables, graphs, and 15 references.

  18. A 4-(o-chlorophenyl)-2-aminothiazole: Microwave assisted synthesis, spectral, thermal, XRD and biological studies

    Science.gov (United States)

    Rajmane, S. V.; Ubale, V. P.; Lawand, A. S.; Nalawade, A. M.; Karale, N. N.; More, P. G.

    2013-11-01

    A 4-(o-chlorophenyl)-2-aminothiazole (CPAT) has been synthesized by reacting o-chloroacetophenone, iodine and thiourea under microwave irradiation as a green chemistry approach. The reactions proceed selectively and within a couple of minutes giving high yields of the products. The compound was characterized by elemental, spectral (UV-visible, IR, NMR and GC-MS), XRD and thermal analyses. The TG curve of the compound was analyzed to calculate various kinetic parameters (n, E, Z, ΔS and ΔG) by using Coats-Redfern (C.R.), MacCallum-Tanner (M.T.) and Horowitz-Metzger (H.M.) method. The compound was tested for the evaluation of antibacterial activity against B. subtilis and E. coli and antifungal activity against A. niger and C. albicans. The compound was evaluated for their in vitro nematicidal activity on plant parasitic nematode Meloidogyne javanica and molluscicidal activity on fresh water helminthiasis vector snail Lymnea auricularia. The compound is biologically active in very low concentration. X-ray diffraction study suggests a triclinic crystal system for the compound.

  19. A study of flow patterns for staggered cylinders at low Reynolds number by spectral element method

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Li-Chieh; Chen, Chien-Lin; Ye, Jian-Zhi [National Yunlin University of Science and Technology, Taiwan (China)

    2017-06-15

    This study investigates the pattern of flow past two staggered array cylinders using the spectral element method by varying the distance between the cylinders and the angle of incidence (α) at low Reynolds numbers (Re = 100-800). Six flow patterns are identified as Shear layer reattachment (SLR), Induced separation (IS), Vortex impingement (VI), Synchronized vortex shedding (SVS), Vortex pairing and enveloping (VPE), and Vortex pairing splitting and enveloping (VPSE). These flow patterns can be transformed from one to another by changing the distance between the cylinders, the angle of incidence, or Re. SLR, IS and VI flow patterns appear in regimes with small angles of incidence (i.e., α ≤ 30° ) and hold only a single von Karman vortex shedding in a wake with one shedding frequency. SVS, VPE and VPSE flow patterns appear in regimes with large angles of incidence (i.e., 30° ≤ α ≤ 50° ) and present two synchronized von Karman vortices. Quantitative analyses and physical interpretation are also conducted to determine the generation mechanisms of the said flow patterns.

  20. The transition radiation. I: numerical study of the angular and spectral distributions

    International Nuclear Information System (INIS)

    Couillaud, Ch.; Haouat, G.

    1999-01-01

    The optical transition radiation (OTR) is extensively used since many years as a beam visualisation tool on electron accelerators and serves to monitor the beam during its transport adjustment. Its spatial and temporal characteristics make it very attractive as a diagnostic tool and allow measurements of the beam energy and transverse and longitudinal emittances. We present a numerical study of the transition radiation process in the optical region of the radiated spectrum (OTR) and in the higher part (XTR). Spatial and spectral properties are described. They are used to describe experimental observations performed on the ELSA electron-beam facility. An analytical description of the angular distributions of visible radiation emitted by birefringent targets, used as OTR sources, is also proposed. We also analyze interference phenomena between two OTR sources and show the advantage of using this interferometer as a diagnostic tool for tenth MeV electron accelerators. At last, we present an analytical model allowing to design a soft X-ray source to be installed on the ELSA facility and using either a multi-foil stack or a multilayer of two materials of different permittivities. (authors)

  1. A COMPARISON STUDY OF DIFFERENT MARKER SELECTION METHODS FOR SPECTRAL-SPATIAL CLASSIFICATION OF HYPERSPECTRAL IMAGES

    Directory of Open Access Journals (Sweden)

    D. Akbari

    2015-12-01

    Full Text Available An effective approach based on the Minimum Spanning Forest (MSF, grown from automatically selected markers using Support Vector Machines (SVM, has been proposed for spectral-spatial classification of hyperspectral images by Tarabalka et al. This paper aims at improving this approach by using image segmentation to integrate the spatial information into marker selection process. In this study, the markers are extracted from the classification maps, obtained by both SVM and segmentation algorithms, and then are used to build the MSF. The segmentation algorithms are the watershed, expectation maximization (EM and hierarchical clustering. These algorithms are used in parallel and independently to segment the image. Moreover, the pixels of each class, with the largest population in the classification map, are kept for each region of the segmentation map. Lastly, the most reliable classified pixels are chosen from among the exiting pixels as markers. Two benchmark urban hyperspectral datasets are used for evaluation: Washington DC Mall and Berlin. The results of our experiments indicate that, compared to the original MSF approach, the marker selection using segmentation algorithms leads in more accurate classification maps.

  2. Quality control of X-ray films with blue spectral sensitivity: comparative study

    International Nuclear Information System (INIS)

    Carrasco, F.; Ruiz Cruces, R.; Sendra, F.; Diez de los rios, A.

    1994-01-01

    In this work, seven X-ray films with blue-ultraviolet spectral sensitivity have been studied by means of light sensitometry, x-ray sensitometry and spatial resolution test. Three screens of different composition and speed were use. Only the films HPX44 and RG showed a high base plus for (>0,30), the remaining films maintained their values between 0,21 and 0,26. When blue light sensitometry was substituted by green light sensitometry, base plus fog practically did not show variations and gradient and speed changed less than 4% and 10% respectively. Speed and Gradient must be calculated from the relation between exposition and optical density, avoiding parameters referred to type optical density of a given step of the wedge. Two films with high speed (RG and HPX 44), four films with medium speed (Curix RP2, NewRX, Cronex 4 and X-Omat S) and one film with low speed but high resolution (Cronex 7) have been found. The obtained results present useful comparative data to select and adequate film according to the characteristic of the x-ray examination and the available screens. (Author)

  3. Spectral and photometric studies of the polar USNO-A2.0 0825-18396733

    Science.gov (United States)

    Gabdeev, M. M.; Borisov, N. V.; Shimansky, V. V.; Spiridonova, O. I.

    2015-03-01

    Results of photometric and spectral studies of the new magnetic cataclysmic variable (polar) USNO-A2.0 0825-18396733 are presented. Photometric data in the B, V, and R c filters show that this object exhibits a red excess of R c - V = 1 m . A red continuum with superposed strong single-peaked Balmer emission lines and HeII λ4686 Å emission, weak lines of neutral helium, and lines of heavy elements are observed in the object's spectra. Doppler maps constructed using the hydrogen and ionized-helium lines indicate that these lines form near the inner Lagrangian point, and that their formation is associated with an accretion stream. The spectra and radial-velocity curves indicate the eclipse of the white dwarf in the system to be partial. Radial-velocity curves derived for emission lines are used to estimate the component masses. The mass of the white dwarf is estimated to be 0.71-0.78 M ⊙, and the mass of the red dwarf to be 0.18-0.20 M ⊙.

  4. Bioavailable atmospheric phosphorous supply to the global ocean: a 3-D global modeling study

    Science.gov (United States)

    Myriokefalitakis, Stelios; Nenes, Athanasios; Baker, Alex R.; Mihalopoulos, Nikolaos; Kanakidou, Maria

    2016-12-01

    The atmospheric cycle of phosphorus (P) is parameterized here in a state-of-the-art global 3-D chemistry transport model, taking into account primary emissions of total P (TP) and soluble P (DP) associated with mineral dust, combustion particles from natural and anthropogenic sources, bioaerosols, sea spray and volcanic aerosols. For the present day, global TP emissions are calculated to be roughly 1.33 Tg-P yr-1, with the mineral sources contributing more than 80 % to these emissions. The P solubilization from mineral dust under acidic atmospheric conditions is also parameterized in the model and is calculated to contribute about one-third (0.14 Tg-P yr-1) of the global DP atmospheric source. To our knowledge, a unique aspect of our global study is the explicit modeling of the evolution of phosphorus speciation in the atmosphere. The simulated present-day global annual DP deposition flux is 0.45 Tg-P yr-1 (about 40 % over oceans), showing a strong spatial and temporal variability. Present-day simulations of atmospheric P aerosol concentrations and deposition fluxes are satisfactory compared with available observations, indicating however an underestimate of about 70 % on current knowledge of the sources that drive the P atmospheric cycle. Sensitivity simulations using preindustrial (year 1850) anthropogenic and biomass burning emission scenarios showed a present-day increase of 75 % in the P solubilization flux from mineral dust, i.e., the rate at which P is converted into soluble forms, compared to preindustrial times, due to increasing atmospheric acidity over the last 150 years. Future reductions in air pollutants due to the implementation of air-quality regulations are expected to decrease the P solubilization flux from mineral dust by about 30 % in the year 2100 compared to the present day. Considering, however, that all the P contained in bioaerosols is readily available for uptake by marine organisms, and also accounting for all other DP sources, a total

  5. Stopped-flow studies of spectral changes in human serum albumin following an alkaline pH jump

    DEFF Research Database (Denmark)

    Honoré, B

    1987-01-01

    A stopped-flow technique was used to study the spectral changes occurring in albumin following a pH jump from 11.3 to 11.8 at 25 degrees C. Ultraviolet difference spectra between various albumin species participating in the process are reported. These spectra are similar in shape to the difference...

  6. An Exercise on Calibration: DRIFTS Study of Binary Mixtures of Calcite and Dolomite with Partially Overlapping Spectral Features

    Science.gov (United States)

    De Lorenzi Pezzolo, Alessandra

    2013-01-01

    Unlike most spectroscopic calibrations that are based on the study of well-separated features ascribable to the different components, this laboratory experience is especially designed to exploit spectral features that are nearly overlapping. The investigated system consists of a binary mixture of two commonly occurring minerals, calcite and…

  7. A Comparison Study of Vector Velocity, Spectral Doppler and Magnetic Resonance of Blood Flow in the Common Carotid Artery

    DEFF Research Database (Denmark)

    Brandt, Andreas Hjelm; Hansen, Kristoffer Lindskov; Ewertsen, Caroline

    2018-01-01

    Magnetic resonance phase contrast angiography (MRA) is the gold standard for blood flow evaluation. Spectral Doppler ultrasound (SDU) is the first clinical choice, although the method is angle dependent. Vector flow imaging (VFI) is an angle-independent ultrasound method. The aim of the study...

  8. Capability of space-spectral analysis used for studying underground nuclear explosions effect on ground surface condition

    International Nuclear Information System (INIS)

    Melent'ev, M.I.; Velikanov, A.E.

    2003-01-01

    The article describes the results of the work of study of the influence underground nucleus blasts (UNB) on condition of the day surface of the site Balapan on the territory of Semipalatinsk Test Site using materials of remote space sensing. The estimation of the cosmic spectral analysis information density is given for revealing the post-explosive geo- dynamic processes. (author)

  9. Study on spectral entropy of two-phase flow density wave instability

    International Nuclear Information System (INIS)

    Zhang Zuoyi

    1992-05-01

    By using mathematic proof, spectral entropy calculations for simple examples and a practical two-phase flow system, it has been proved that under the same stochastic input, the output spectral entropy of a stable linear system is in maximum, while for an unstable linear system, its entropy is in relative lower level. Because the spectral entropy describes the output uncertainty of a system and the second law of thermodynamics rules the direction of natural tendency, the spontaneous process can develop only toward the direction of uncertainty increasing, and the opposite is impossible. It seems that the physical mechanism of the stability of a system can be explained as following: Any deviation from its original state of a stable system will reduce the spectral entropy and violate the natural tendency so that the system will return to original state. On the contrary, the deviation from its original state of an unstable system will increase the spectral entropy that will enhance the deviation and the system will be further away from its original state

  10. A complex guided spectral transform Lanczos method for studying quantum resonance states

    International Nuclear Information System (INIS)

    Yu, Hua-Gen

    2014-01-01

    A complex guided spectral transform Lanczos (cGSTL) algorithm is proposed to compute both bound and resonance states including energies, widths and wavefunctions. The algorithm comprises of two layers of complex-symmetric Lanczos iterations. A short inner layer iteration produces a set of complex formally orthogonal Lanczos (cFOL) polynomials. They are used to span the guided spectral transform function determined by a retarded Green operator. An outer layer iteration is then carried out with the transform function to compute the eigen-pairs of the system. The guided spectral transform function is designed to have the same wavefunctions as the eigenstates of the original Hamiltonian in the spectral range of interest. Therefore the energies and/or widths of bound or resonance states can be easily computed with their wavefunctions or by using a root-searching method from the guided spectral transform surface. The new cGSTL algorithm is applied to bound and resonance states of HO, and compared to previous calculations

  11. A Fundamental Study on Spectrum Center Estimation of Solar Spectral Irradiation by the Statistical Pattern Recognition

    Science.gov (United States)

    Iijima, Aya; Suzuki, Kazumi; Wakao, Shinji; Kawasaki, Norihiro; Usami, Akira

    With a background of environmental problems and energy issues, it is expected that PV systems will be introduced rapidly and connected with power grids on a large scale in the future. For this reason, the concern to which PV power generation will affect supply and demand adjustment in electric power in the future arises and the technique of correctly grasping the PV power generation becomes increasingly important. The PV power generation depends on solar irradiance, temperature of a module and solar spectral irradiance. Solar spectral irradiance is distribution of the strength of the light for every wavelength. As the spectrum sensitivity of solar cell depends on kind of solar cell, it becomes important for exact grasp of PV power generation. Especially the preparation of solar spectral irradiance is, however, not easy because the observational instrument of solar spectral irradiance is expensive. With this background, in this paper, we propose a new method based on statistical pattern recognition for estimating the spectrum center which is representative index of solar spectral irradiance. Some numerical examples obtained by the proposed method are also presented.

  12. Multiple Cultures of Doing Geography Facilitate Global Studies

    Science.gov (United States)

    Ahamer, Gilbert

    2013-01-01

    Purpose: This article aims to explain why geography is a prime discipline for analysing globalisation and a multicultural view of Global Studies. The generic approach of human geography to first select an appropriate methodology is taken as a key approach. Design/methodology/approach: Concepts from aggregate disciplines such as history, economics,…

  13. Integrating Curriculum: A Case Study of Teaching Global Education

    Science.gov (United States)

    Ferguson-Patrick, Kate; Reynolds, Ruth; Macqueen, Suzanne

    2018-01-01

    Despite widespread support for integrated approaches to teaching, classroom practice reveals a lack of implementation. This paper explores challenges and opportunities in teaching an integrated curriculum, and connects this with the contemporary notion of a twenty-first century curriculum and pedagogy. A case study of Global Education (GE) is used…

  14. Assessment of global phase uncertainty in case-control studies

    Directory of Open Access Journals (Sweden)

    van Houwelingen Hans C

    2009-09-01

    Full Text Available Abstract Background In haplotype-based candidate gene studies a problem is that the genotype data are unphased, which results in haplotype ambiguity. The measure 1 quantifies haplotype predictability from genotype data. It is computed for each individual haplotype, and for a measure of global relative efficiency a minimum value is suggested. Alternatively, we developed methods directly based on the information content of haplotype frequency estimates to obtain global relative efficiency measures: and based on A- and D-optimality, respectively. All three methods are designed for single populations; they can be applied in cases only, controls only or the whole data. Therefore they are not necessarily optimal for haplotype testing in case-control studies. Results A new global relative efficiency measure was derived to maximize power of a simple test statistic that compares haplotype frequencies in cases and controls. Application to real data showed that our proposed method gave a clear and summarizing measure for the case-control study conducted. Additionally this measure might be used for selection of individuals, who have the highest potential for improving power by resolving phase ambiguity. Conclusion Instead of using relative efficiency measure for cases only, controls only or their combined data, we link uncertainty measure to case-control studies directly. Hence, our global efficiency measure might be useful to assess whether data are informative or have enough power for estimation of a specific haplotype risk.

  15. Study on text mining algorithm for ultrasound examination of chronic liver diseases based on spectral clustering

    Science.gov (United States)

    Chang, Bingguo; Chen, Xiaofei

    2018-05-01

    Ultrasonography is an important examination for the diagnosis of chronic liver disease. The doctor gives the liver indicators and suggests the patient's condition according to the description of ultrasound report. With the rapid increase in the amount of data of ultrasound report, the workload of professional physician to manually distinguish ultrasound results significantly increases. In this paper, we use the spectral clustering method to cluster analysis of the description of the ultrasound report, and automatically generate the ultrasonic diagnostic diagnosis by machine learning. 110 groups ultrasound examination report of chronic liver disease were selected as test samples in this experiment, and the results were validated by spectral clustering and compared with k-means clustering algorithm. The results show that the accuracy of spectral clustering is 92.73%, which is higher than that of k-means clustering algorithm, which provides a powerful ultrasound-assisted diagnosis for patients with chronic liver disease.

  16. EEG spectral coherence data distinguish chronic fatigue syndrome patients from healthy controls and depressed patients--a case control study.

    Science.gov (United States)

    Duffy, Frank H; McAnulty, Gloria B; McCreary, Michelle C; Cuchural, George J; Komaroff, Anthony L

    2011-07-01

    Previous studies suggest central nervous system involvement in chronic fatigue syndrome (CFS), yet there are no established diagnostic criteria. CFS may be difficult to differentiate from clinical depression. The study's objective was to determine if spectral coherence, a computational derivative of spectral analysis of the electroencephalogram (EEG), could distinguish patients with CFS from healthy control subjects and not erroneously classify depressed patients as having CFS. This is a study, conducted in an academic medical center electroencephalography laboratory, of 632 subjects: 390 healthy normal controls, 70 patients with carefully defined CFS, 24 with major depression, and 148 with general fatigue. Aside from fatigue, all patients were medically healthy by history and examination. EEGs were obtained and spectral coherences calculated after extensive artifact removal. Principal Components Analysis identified coherence factors and corresponding factor loading patterns. Discriminant analysis determined whether spectral coherence factors could reliably discriminate CFS patients from healthy control subjects without misclassifying depression as CFS. Analysis of EEG coherence data from a large sample (n = 632) of patients and healthy controls identified 40 factors explaining 55.6% total variance. Factors showed highly significant group differentiation (p EEG spectral coherence analysis identified unmedicated patients with CFS and healthy control subjects without misclassifying depressed patients as CFS, providing evidence that CFS patients demonstrate brain physiology that is not observed in healthy normals or patients with major depression. Studies of new CFS patients and comparison groups are required to determine the possible clinical utility of this test. The results concur with other studies finding neurological abnormalities in CFS, and implicate temporal lobe involvement in CFS pathophysiology.

  17. Element-specific spectral imaging of multiple contrast agents: a phantom study

    Science.gov (United States)

    Panta, R. K.; Bell, S. T.; Healy, J. L.; Aamir, R.; Bateman, C. J.; Moghiseh, M.; Butler, A. P. H.; Anderson, N. G.

    2018-02-01

    This work demonstrates the feasibility of simultaneous discrimination of multiple contrast agents based on their element-specific and energy-dependent X-ray attenuation properties using a pre-clinical photon-counting spectral CT. We used a photon-counting based pre-clinical spectral CT scanner with four energy thresholds to measure the X-ray attenuation properties of various concentrations of iodine (9, 18 and 36 mg/ml), gadolinium (2, 4 and 8 mg/ml) and gold (2, 4 and 8 mg/ml) based contrast agents, calcium chloride (140 and 280 mg/ml) and water. We evaluated the spectral imaging performances of different energy threshold schemes between 25 to 82 keV at 118 kVp, based on K-factor and signal-to-noise ratio and ranked them. K-factor was defined as the X-ray attenuation in the K-edge containing energy range divided by the X-ray attenuation in the preceding energy range, expressed as a percentage. We evaluated the effectiveness of the optimised energy selection to discriminate all three contrast agents in a phantom of 33 mm diameter. A photon-counting spectral CT using four energy thresholds of 27, 33, 49 and 81 keV at 118 kVp simultaneously discriminated three contrast agents based on iodine, gadolinium and gold at various concentrations using their K-edge and energy-dependent X-ray attenuation features in a single scan. A ranking method to evaluate spectral imaging performance enabled energy thresholds to be optimised to discriminate iodine, gadolinium and gold contrast agents in a single spectral CT scan. Simultaneous discrimination of multiple contrast agents in a single scan is likely to open up new possibilities of improving the accuracy of disease diagnosis by simultaneously imaging multiple bio-markers each labelled with a nano-contrast agent.

  18. The transition radiation. I: numerical study of the angular and spectral distributions; Le rayonnement de transition optique. I: etude numerique des distributions angulaires et spectrales

    Energy Technology Data Exchange (ETDEWEB)

    Couillaud, Ch.; Haouat, G

    1999-07-01

    The optical transition radiation (OTR) is extensively used since many years as a beam visualisation tool on electron accelerators and serves to monitor the beam during its transport adjustment. Its spatial and temporal characteristics make it very attractive as a diagnostic tool and allow measurements of the beam energy and transverse and longitudinal emittances. We present a numerical study of the transition radiation process in the optical region of the radiated spectrum (OTR) and in the higher part (XTR). Spatial and spectral properties are described. They are used to describe experimental observations performed on the ELSA electron-beam facility. An analytical description of the angular distributions of visible radiation emitted by birefringent targets, used as OTR sources, is also proposed. We also analyze interference phenomena between two OTR sources and show the advantage of using this interferometer as a diagnostic tool for tenth MeV electron accelerators. At last, we present an analytical model allowing to design a soft X-ray source to be installed on the ELSA facility and using either a multi-foil stack or a multilayer of two materials of different permittivities. (authors)

  19. Evaluation Study of Fast Spectral Estimators Using In-vivo Data

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Lindskov; Gran, Fredrik; Pedersen, Mads Møller

    2009-01-01

    Spectrograms in medical ultrasound are usually estimated with Welch's method (WM). To achieve sufficient spectral resolution and contrast, WM uses an observation window (OW) of up to 256 emissions per estimate. Two adaptive filterbank methods have been suggested to reduce the OW: Blood spectral...... Power Capon (BPC) and the Blood Amplitude and Phase EStimation method (BAPES). Ten volunteers were scanned over the carotid artery. From each dataset, 28 spectrograms were produced by combining four approaches (WM with a Hanning window (W.HAN), WM with a boxcar window (W.BOX), BPC and BAPES) and seven...

  20. Study of the heat transfers spectral radiation - conduction - natural convection in hybrid photovoltaic systems for buildings

    International Nuclear Information System (INIS)

    Muresan, C.

    2005-01-01

    numerical solution of the Radiative Transfer Equation in diffused part in the case of a mono-dimensional plane geometry. The directional discretizations of each layer are selected in such a way that the discrete directions of one of the layers correspond to those refracted of the close layer and this makes it possible to avoid the use of approximations related to non coincidence of the discrete directions of a layer with those refracted by the close layer. Directional quadratures are then established in an adaptive way in each layer and for each spectral frequency. The results obtained are validated by an approach of Monte Carlo type. The coupling of this model with a Low Reynolds number RANS model will be carried out. This will be done in order to study the convective heat transfers in natural convection for configurations of double facade integration under consideration within the framework of PRI CNRS. The comparison of this model is carried out for experimental configurations of vertical channel type uniformly heated in natural convection. The prospects for this stage are multiple and consist of analyzing the influence of the mode of flow on the thermal pulling of the hybrid components, the effects of the positioning of modules statement, the air gap between the two frontages and the boundary conditions thermal generated by the modules. Lastly, in order to supplement the energy balance of such components and more particularly that governs the thermal behavior of a photosensitive cell, the electric phenomenon of conversion is approached in adequacy with the level of modeling of the coupled thermal transfers radiation - conduction within a PV component. To carry this out, we can consider the local power of spectral radiation absorbed and converted into electric output. (author)

  1. Spectral, stoichiometric ratio, physicochemical, polarity and photostability studies of newly synthesized chalcone dye in organized media

    International Nuclear Information System (INIS)

    Marwani, Hadi M.; Asiri, Abdullah M.; Khan, Salman A.

    2013-01-01

    The main focus of this study was to investigate spectroscopic properties, stoichiometric ratios, physicochemical parameters, polarity and photostability behaviors of newly synthesized chalcone dye in organized media. The chalcone dye, 1-(2,5-Dimethyl-thiophen-3-yl)-3-(9-etnyl-9H-carbazol-3-yl)-propenone (DTEP), was prepared by the reaction of carbazole aldehyde with 3-acetyl-2,5-dimethythiophene. Data obtained from FT-IR, 1 H-–NMR, 13 C-NMR and elemental analysis were consistent with chemical structure of newly prepared DTEP. Increases in fluorescence intensities of DTEP with cetyltrimethyl ammonium bromide (CTAB) were observed. In comparison of fluorescence intensities for DTEP with CTAB, reductions in fluorescence intensities for DTEP with sodium dodecyl sulfate (SDS) were noticed under the same experimental and instrumental conditions. Additionally, Benesi–Hildebrand method was applied to determine stoichiometric ratios and association constants of DTEP with CTAB and SDS. Stern–Volmer plot was used in order to further confirm the stoichiometric ratio and association constant of DTEP with SDS. Physicochemical parameters such as singlet absorption, molar absorptivity, oscillator strength, dipole moment and fluorescence quantum yield of DTEP were also determined. Fluorescence polarity study displayed that DTEP was sensitive to the polarity of the microenvironment provided by different solvents. Finally, fluorescence steady-state measurements revealed that DTEP has high photostability against photobleaching. -- Highlights: ► Mechanistic understanding of molecular structure of newly synthesized chalcone dye. ► Exploring spectral behaviors and physicochemical parameters of chalcone dye. ► Determination of stoichiometric ratios and association constants of chalcone dye. ► Determination of fluorescence quantum yield in different solvents. ► High photostability against photobleaching of chalcone dye was observed

  2. Laboratory Study of Aliphatic Organic Spectral Signatures and Applications to Ceres and Primitive Asteroids

    Science.gov (United States)

    Kaplan, H. H.; Milliken, R.

    2017-12-01

    Aliphatic organics were recently discovered on the surface of Ceres with Dawn's Visible and InfraRed (VIR) mapping spectrometer, which has implications for prebiotic chemistry of Ceres and other asteroids. An absorption in the spectrum at 3.4 µm was used to identify and provide initial estimates of the amount of organic material. We have studied the 3.4 µm absorption in reflectance spectra of bulk rock and meteorite powders and isolated organic materials in the NASA RELAB facility at Brown University to determine how organic composition and abundance affects absorption strength. Reflectance spectra of insoluble organic matter (IOM) extracted from carbonaceous chondrites were measured from 0.35 - 25 µm. These IOM have known elemental (H, C, N, O) and isotopic compositions that were compared with spectral properties. Bulk meteorites were measured as chips and particulates over the same wavelength range. Despite overall low reflectance values (albedo IOM samples, specifically those with a H/C ratio greater than 0.4. The absorption strength (band depth) increases with increasing H/C ratio, which corroborates similar findings in our previous study of sedimentary rocks and isolated kerogens. The absorption strength in the bulk meteorites reflects both H/C of the IOM and the concentration of IOM in the inorganic (mineral) matrix. Overlapping absorptions from carbonates and phyllosilicates (OH/H2O) can also influence the aliphatic organic bands in bulk rocks and meteorites. This laboratory work provides a foundation that can be used to constrain the composition of Ceres' aliphatic organic matter using band depth as a proxy for H/C. Reflectance spectra collected for this work will also be used to model the Dawn VIR data and obtain abundance and H/C estimates assuming that the organic material on Ceres' surface is similar to carbonaceous chondrite IOM. These spectra and findings can aid interpretation of reflectance data from Ceres and other asteroid missions, such as

  3. Computer-aided diagnosis of contrast-enhanced spectral mammography: A feasibility study.

    Science.gov (United States)

    Patel, Bhavika K; Ranjbar, Sara; Wu, Teresa; Pockaj, Barbara A; Li, Jing; Zhang, Nan; Lobbes, Mark; Zhang, Bin; Mitchell, J Ross

    2018-01-01

    To evaluate whether the use of a computer-aided diagnosis-contrast-enhanced spectral mammography (CAD-CESM) tool can further increase the diagnostic performance of CESM compared with that of experienced radiologists. This IRB-approved retrospective study analyzed 50 lesions described on CESM from August 2014 to December 2015. Histopathologic analyses, used as the criterion standard, revealed 24 benign and 26 malignant lesions. An expert breast radiologist manually outlined lesion boundaries on the different views. A set of morphologic and textural features were then extracted from the low-energy and recombined images. Machine-learning algorithms with feature selection were used along with statistical analysis to reduce, select, and combine features. Selected features were then used to construct a predictive model using a support vector machine (SVM) classification method in a leave-one-out-cross-validation approach. The classification performance was compared against the diagnostic predictions of 2 breast radiologists with access to the same CESM cases. Based on the SVM classification, CAD-CESM correctly identified 45 of 50 lesions in the cohort, resulting in an overall accuracy of 90%. The detection rate for the malignant group was 88% (3 false-negative cases) and 92% for the benign group (2 false-positive cases). Compared with the model, radiologist 1 had an overall accuracy of 78% and a detection rate of 92% (2 false-negative cases) for the malignant group and 62% (10 false-positive cases) for the benign group. Radiologist 2 had an overall accuracy of 86% and a detection rate of 100% for the malignant group and 71% (8 false-positive cases) for the benign group. The results of our feasibility study suggest that a CAD-CESM tool can provide complementary information to radiologists, mainly by reducing the number of false-positive findings. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Application of spectral hole burning to the study of in vitro cellular systems

    Energy Technology Data Exchange (ETDEWEB)

    Milanovich, Nebojsa [Iowa State Univ., Ames, IA (United States)

    1999-11-08

    Chapter 1 of this thesis describes the various stages of tumor development and a multitude of diagnostic techniques used to detect cancer. Chapter 2 gives an overview of the aspects of hole burning spectroscopy important for its application to the study of cellular systems. Chapter 3 gives general descriptions of cellular organelles, structures, and physical properties that can serve as possible markers for the differentiation of normal and cancerous cells. Also described in Chapter 3 are the principles of cryobiology important for low temperature spectroscopy of cells, characterization of MCF-10F (normal) and MCF-7 (cancer) cells lines which will serve as model systems, and cellular characteristics of aluminum phthalocyanine tetrasulfonate (APT), which was used as the test probe. Chapters 4 and 5 are previously published papers by the author pertaining to the results obtained from the application of hole burning to the study of cellular systems. Chapter 4 presents the first results obtained by spectral hole burning of cellular systems and Chapter 5 gives results for the differentiation of MCF-10F and MCF-7 cells stained with APT by an external applied electric (Stark) field. A general conclusion is presented in Chapter 6. Appendices A and B provide additional characterization of the cell/probe model systems. Appendix A describes the uptake and subcellular distribution of APT in MCF-10F and MCF-7 cells and Appendix B compares the hole burning characteristics of APT in cells when the cells are in suspension and when they are examined while adhering to a glass coverslip. Appendix C presents preliminary results for a novel probe molecule, referred to as a molecular thumbtack, designed by the authors for use in future hole burning applications to cellular systems.

  5. Spectral stratigraphy

    Science.gov (United States)

    Lang, Harold R.

    1991-01-01

    A new approach to stratigraphic analysis is described which uses photogeologic and spectral interpretation of multispectral remote sensing data combined with topographic information to determine the attitude, thickness, and lithology of strata exposed at the surface. The new stratigraphic procedure is illustrated by examples in the literature. The published results demonstrate the potential of spectral stratigraphy for mapping strata, determining dip and strike, measuring and correlating stratigraphic sequences, defining lithofacies, mapping biofacies, and interpreting geological structures.

  6. Spectral changes in conifers subjected to air pollution and water stress: Experimental studies

    Science.gov (United States)

    Westman, Walter E.; Price, Curtis V.

    1988-01-01

    The roles of leaf anatomy, moisture and pigment content, and number of leaf layers on spectral reflectance in healthy, pollution-stressed, and water-stressed conifer needles were examined experimentally. Jeffrey pine (Pinus jeffreyi) and giant sequoia (Sequoiadendron gigantea) were exposed to ozone and acid mist treatments in fumigation chambers; red pine (Pinus resinosa) needles were artificially dried. Infrared reflectance from stacked needles rose with free water loss. In an air-drying experiment, cell volume reductions induced by loss of turgor caused near-infrared reflectance (TM band 4) to drop after most free water was lost. Under acid mist fumigation, stunting of tissue development similarly reduced band 4 reflectance. Both artificial drying and pollutant fumigation caused a blue shift of the red edge of spectral reflectance curves in conifers, attributable to chlorophyll denaturation. Thematic mapper band ratio 4/3 fell and 5/4 rose with increasing pollution stress on artificial drying. Loss of water by air-drying, freeze-drying, or oven-drying enhanced spectral features, due in part to greater scattering and reduced water absorption. Grinding of the leaf tissue further enhanced the spectral features by increasing reflecting surfaces and path length. In a leaf-stacking experiment, an asymptote in visible and infrared reflectance was reached at 7-8 needle layers of red pine.

  7. An empirical study on the performance of spectral manifold learning techniques

    DEFF Research Database (Denmark)

    Mysling, Peter; Hauberg, Søren; Pedersen, Kim Steenstrup

    2011-01-01

    In recent years, there has been a surge of interest in spectral manifold learning techniques. Despite the interest, only little work has focused on the empirical behavior of these techniques. We construct synthetic data of variable complexity and observe the performance of the techniques as they ...

  8. MULTI-WAVELENGTH POLARIMETRY AND SPECTRAL STUDY OF THE M87 JET DURING 2002–2008

    Energy Technology Data Exchange (ETDEWEB)

    Avachat, Sayali S.; Perlman, Eric S. [Department of Physics and Space Sciences, 150 W. University Boulevard, Florida Institute of Technology, Melbourne, FL 32901 (United States); Adams, Steven C. [Department of Physics and Astronomy, University of Georgia, Athens, GA, 30605 (United States); Cara, Mihai; Sparks, William B. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Owen, Frazer [National Radio Astronomy Observatory, Array Operations Center, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801-0387 (United States); Georganopoulos, Markos [Department of Physics, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States)

    2016-11-20

    We present a multi-wavelength polarimetric and spectral study of the M87 jet obtained at sub-arcsecond resolution between 2002 and 2008. The observations include multi-band archival VLA polarimetry data sets along with Hubble Space Telescope ( HST ) imaging polarimetry. These observations have better angular resolution than previous work by factors of 2–3 and in addition, allow us to explore the time domain. These observations envelop the huge flare in HST-1 located 0.″86 from the nucleus. The increased resolution enables us to view more structure in each knot, showing several resolved sub-components. We also see apparent helical structure in the polarization vectors in several knots, with polarization vectors turning either clockwise or counterclockwise near the flux maxima in various places as well as showing filamentary undulations. Some of these characteristics are correlated with flux and polarization maxima while others are not. We also examine the total flux and fractional polarization and look for changes in both radio and optical since the observations of Perlman et al. (1999) and test them against various models based on shocks and instabilities in the jet. Our results are broadly consistent with previous spine-sheath models and recollimation shock models; however, they require additional combinations of features to explain the observed complexity, e.g., shearing of magnetic field lines near the jet surface and compression of the toroidal component near shocks. In particular, in many regions we find apparently helical features both in total flux and polarization. We discuss the physical interpretation of these features.

  9. Accuracy of bone mineral density quantification using dual-layer spectral detector CT: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Hamersvelt, Robbert W. van; Schilham, Arnold M.R.; Harder, Annemarie M. den; Leiner, Tim; Jong, Pim A. de; Willemink, Martin J. [University Medical Centre Utrecht, Department of Radiology, P.O. Box 85500, Utrecht (Netherlands); Engelke, Klaus [University of Erlangen-Nuernberg, Institute of Medical Physics, Erlangen (Germany); Keizer, Bart de [University Medical Centre Utrecht, Department of Nuclear Medicine, Utrecht (Netherlands); Verhaar, Harald J. [University Medical Centre Utrecht, Department of Geriatric Medicine, Utrecht (Netherlands)

    2017-10-15

    To investigate the accuracy of bone mineral density (BMD) quantification using dual-layer spectral detector CT (SDCT) at various scan protocols. Two validated anthropomorphic phantoms containing inserts of 50-200 mg/cm{sup 3} calcium hydroxyapatite (HA) were scanned using a 64-slice SDCT scanner at various acquisition protocols (120 and 140 kVp, and 50, 100 and 200 mAs). Regions of interest (ROIs) were placed in each insert and mean attenuation profiles at monochromatic energy levels (90-200 keV) were constructed. These profiles were fitted to attenuation profiles of pure HA and water to calculate HA concentrations. For comparison, one phantom was scanned using dual energy X-ray absorptiometry (DXA). At both 120 and 140 kVp, excellent correlations (R = 0.97, P < 0.001) were found between true and measured HA concentrations. Mean error for all measurements at 120 kVp was -5.6 ± 5.7 mg/cm{sup 3} (-3.6 ± 3.2%) and at 140 kVp -2.4 ± 3.7 mg/cm{sup 3} (-0.8 ± 2.8%). Mean measurement errors were smaller than 6% for all acquisition protocols. Strong linear correlations (R{sup 2} ≥ 0.970, P < 0.001) with DXA were found. SDCT allows for accurate BMD quantification and potentially opens up the possibility for osteoporosis evaluation and opportunistic screening in patients undergoing SDCT for other clinical indications. However, patient studies are needed to extend and translate our findings. (orig.)

  10. Synthesis, spectral, thermal, potentiometric and antimicrobial studies of transition metal complexes of tridentate ligand

    Directory of Open Access Journals (Sweden)

    Sarika M. Jadhav

    2014-01-01

    Full Text Available A series of metal complexes of Cu(II, Ni(II, Co(II, Fe(III and Mn(II have been synthesized with newly synthesized biologically active tridentate ligand. The ligand was synthesized by condensation of dehydroacetic acid (3-acetyl-6-methyl-(2H pyran-2,4(3H-dione or DHA, o-phenylene diamine and fluoro benzaldehyde and characterized by elemental analysis, molar conductivity, magnetic susceptibility, thermal analysis, X-ray diffraction, IR, 1H-NMR, UV–Vis spectroscopy and mass spectra. From the analytical data, the stoichiometry of the complexes was found to be 1:2 (metal:ligand with octahedral geometry. The molar conductance values suggest the non-electrolyte nature of metal complexes. The IR spectral data suggest that the ligand behaves as a dibasic tridentate ligand with ONN donor atoms sequence towards central metal ion. Thermal behaviour (TG/DTA and kinetic parameters calculated by the Coats–Redfern and Horowitz–Metzger method suggest more ordered activated state in complex formation. To investigate the relationship between stability constants of metal complexes and antimicrobial activity, the dissociation constants of Schiff bases and stability constants of their binary metal complexes have been determined potentiometrically in THF–water (60:40% solution at 25 ± 1 °C and at 0.1 M NaClO4 ionic strength. The potentiometric study suggests 1:1 and 1:2 complexation. Antibacterial and antifungal activities in vitro were performed against Staphylococcus aureus, Escherichia coli and Aspergillus niger, Trichoderma, respectively. The stability constants of the metal complexes were calculated by the Irving–Rosotti method. A relation between the stability constant and antimicrobial activity of complexes has been discussed. It is observed that the activity enhances upon complexation and the order of antifungal activity is in accordance with stability order of metal ions.

  11. WE-FG-207B-12: Quantitative Evaluation of a Spectral CT Scanner in a Phantom Study: Results of Spectral Reconstructions

    International Nuclear Information System (INIS)

    Duan, X; Arbique, G; Guild, J; Anderson, J; Yagil, Y

    2016-01-01

    Purpose: To evaluate the quantitative image quality of spectral reconstructions of phantom data from a spectral CT scanner. Methods: The spectral CT scanner (IQon Spectral CT, Philips Healthcare) is equipped with a dual-layer detector and generates conventional 80-140 kVp images and variety of spectral reconstructions, e.g., virtual monochromatic (VM) images, virtual non-contrast (VNC) images, iodine maps, and effective atomic number (Z) images. A cylindrical solid water phantom (Gammex 472, 33 cm diameter and 5 cm thick) with iodine (2.0-20.0 mg I/ml) and calcium (50-600 mg/ml) rod inserts was scanned at 120 kVp and 27 mGy CTDIvol. Spectral reconstructions were evaluated by comparing image measurements with theoretical values calculated from nominal rod compositions provided by the phantom manufacturer. The theoretical VNC was calculated using water and iodine basis material decomposition, and the theoretical Z was calculated using two common methods, the chemical formula method (Z1) and the dual-energy ratio method (Z2). Results: Beam-hardening-like artifacts between high-attenuation calcium rods (≥300 mg/ml, >800 HU) influenced quantitative measurements, so the quantitative analysis was only performed on iodine rods using the images from the scan with all the calcium rods removed. The CT numbers of the iodine rods in the VM images (50∼150 keV) were close to theoretical values with average difference of 2.4±6.9 HU. Compared with theoretical values, the average difference for iodine concentration, VNC CT number and effective Z of iodine rods were −0.10±0.38 mg/ml, −0.1±8.2 HU, 0.25±0.06 (Z1) and −0.23±0.07 (Z2). Conclusion: The results indicate that the spectral CT scanner generates quantitatively accurate spectral reconstructions at clinically relevant iodine concentrations. Beam-hardening-like artifacts still exist when high-attenuation objects are present and their impact on patient images needs further investigation. YY is an employee of Philips

  12. WE-FG-207B-12: Quantitative Evaluation of a Spectral CT Scanner in a Phantom Study: Results of Spectral Reconstructions

    Energy Technology Data Exchange (ETDEWEB)

    Duan, X; Arbique, G; Guild, J; Anderson, J [UT Southwestern Medical Center, Dallas, TX (United States); Yagil, Y [Philips Healthcare, Haifa (Israel)

    2016-06-15

    Purpose: To evaluate the quantitative image quality of spectral reconstructions of phantom data from a spectral CT scanner. Methods: The spectral CT scanner (IQon Spectral CT, Philips Healthcare) is equipped with a dual-layer detector and generates conventional 80-140 kVp images and variety of spectral reconstructions, e.g., virtual monochromatic (VM) images, virtual non-contrast (VNC) images, iodine maps, and effective atomic number (Z) images. A cylindrical solid water phantom (Gammex 472, 33 cm diameter and 5 cm thick) with iodine (2.0-20.0 mg I/ml) and calcium (50-600 mg/ml) rod inserts was scanned at 120 kVp and 27 mGy CTDIvol. Spectral reconstructions were evaluated by comparing image measurements with theoretical values calculated from nominal rod compositions provided by the phantom manufacturer. The theoretical VNC was calculated using water and iodine basis material decomposition, and the theoretical Z was calculated using two common methods, the chemical formula method (Z1) and the dual-energy ratio method (Z2). Results: Beam-hardening-like artifacts between high-attenuation calcium rods (≥300 mg/ml, >800 HU) influenced quantitative measurements, so the quantitative analysis was only performed on iodine rods using the images from the scan with all the calcium rods removed. The CT numbers of the iodine rods in the VM images (50∼150 keV) were close to theoretical values with average difference of 2.4±6.9 HU. Compared with theoretical values, the average difference for iodine concentration, VNC CT number and effective Z of iodine rods were −0.10±0.38 mg/ml, −0.1±8.2 HU, 0.25±0.06 (Z1) and −0.23±0.07 (Z2). Conclusion: The results indicate that the spectral CT scanner generates quantitatively accurate spectral reconstructions at clinically relevant iodine concentrations. Beam-hardening-like artifacts still exist when high-attenuation objects are present and their impact on patient images needs further investigation. YY is an employee of Philips

  13. [Study on Application of NIR Spectral Information Screening in Identification of Maca Origin].

    Science.gov (United States)

    Wang, Yuan-zhong; Zhao, Yan-li; Zhang, Ji; Jin, Hang

    2016-02-01

    Medicinal and edible plant Maca is rich in various nutrients and owns great medicinal value. Based on near infrared diffuse reflectance spectra, 139 Maca samples collected from Peru and Yunnan were used to identify their geographical origins. Multiplication signal correction (MSC) coupled with second derivative (SD) and Norris derivative filter (ND) was employed in spectral pretreatment. Spectrum range (7,500-4,061 cm⁻¹) was chosen by spectrum standard deviation. Combined with principal component analysis-mahalanobis distance (PCA-MD), the appropriate number of principal components was selected as 5. Based on the spectrum range and the number of principal components selected, two abnormal samples were eliminated by modular group iterative singular sample diagnosis method. Then, four methods were used to filter spectral variable information, competitive adaptive reweighted sampling (CARS), monte carlo-uninformative variable elimination (MC-UVE), genetic algorithm (GA) and subwindow permutation analysis (SPA). The spectral variable information filtered was evaluated by model population analysis (MPA). The results showed that RMSECV(SPA) > RMSECV(CARS) > RMSECV(MC-UVE) > RMSECV(GA), were 2. 14, 2. 05, 2. 02, and 1. 98, and the spectral variables were 250, 240, 250 and 70, respectively. According to the spectral variable filtered, partial least squares discriminant analysis (PLS-DA) was used to build the model, with random selection of 97 samples as training set, and the other 40 samples as validation set. The results showed that, R²: GA > MC-UVE > CARS > SPA, RMSEC and RMSEP: GA Maca. The method was aimed to lay the foundation for traditional Chinese medicine identification and quality evaluation.

  14. Decision Making Processes for Global Product Development - a Case Study

    DEFF Research Database (Denmark)

    Søndergaard, Erik Stefan; Ahmed-Kristensen, Saeema

    2015-01-01

    Global Product Development (GPD), outsourcing and offshoring of product development is a widespread phenomenon on today’s global economy, and consequently most engineering manufacturing companies will have to make decisions regarding how to organise their product development activities globally...

  15. A study on the globalization of nuclear development

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hwan Sam; Kim, Hyun Jun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-05-01

    Nuclear power technology in Korea has been reached at about 95 % level to self-reliance, which has developed energetically since mid of 1980s. Nowadays, it is required to set up globalization of nuclear policy to ensure the introduction of more advanced technologies and to enlarge the use of their developed technologies. In this study, prospects of nuclear power and wastes management, international safeguards, and international co-operation were analyzed focusing on the International Atomic Energy Agency to support timely the introduction of advanced technologies and assure international nuclear communities of Korean nuclear transparency in order to enhance the national policy for self-reliance on their future technology development. This study can be applied to the efficient implementation of Korean nuclear development policy and globalization policy as well. 3 tabs., 1 fig., 13 refs. (Author).

  16. A study on the globalization of nuclear development

    International Nuclear Information System (INIS)

    Jeong, Hwan Sam; Kim, Hyun Jun

    1996-05-01

    Nuclear power technology in Korea has been reached at about 95 % level to self-reliance, which has developed energetically since mid of 1980s. Nowadays, it is required to set up globalization of nuclear policy to ensure the introduction of more advanced technologies and to enlarge the use of their developed technologies. In this study, prospects of nuclear power and wastes management, international safeguards, and international co-operation were analyzed focusing on the International Atomic Energy Agency to support timely the introduction of advanced technologies and assure international nuclear communities of Korean nuclear transparency in order to enhance the national policy for self-reliance on their future technology development. This study can be applied to the efficient implementation of Korean nuclear development policy and globalization policy as well. 3 tabs., 1 fig., 13 refs. (Author)

  17. Transient global amnesia and neurological events: the Framingham Heart Study

    OpenAIRE

    Jose Rafael Romero; Jose Rafael Romero; Melissa eMercado; Alexa S Beiser; Alexa S Beiser; Alexa S Beiser; Aleksandra ePikula; Aleksandra ePikula; Sudha eSeshadri; Sudha eSeshadri; Margaret eKelly-Hayes; Philip A Wolf; Philip A Wolf; Carlos S Kase; Carlos S Kase

    2013-01-01

    Background/ objective: Transient global amnesia (TGA) is a temporary amnestic syndrome characterized by lack of other focal neurological deficits. Cerebrovascular disease, migraine and seizures have been suggested as underlying mechanisms. TGA may be a risk factor for cerebrovascular or other neurological events. We studied the relation of TGA, vascular risk factors, brain magnetic resonance imaging (MRI) indices of subclinical ischemia and neurological events in a community-based sample. Des...

  18. Application of computed tomography virtual noncontrast spectral imaging in evaluation of hepatic metastases: a preliminary study.

    Science.gov (United States)

    Tian, Shi-Feng; Liu, Ai-Lian; Liu, Jing-Hong; Sun, Mei-Yu; Wang, He-Qing; Liu, Yi-Jun

    2015-03-05

    The objective was to qualitatively and quantitatively evaluate hepatic metastases using computed tomography (CT) virtual noncontrast (VNC) spectral imaging in a retrospective analysis. Forty hepatic metastases patients underwent CT scans including the conventional true noncontrast (TNC) and the tri-phasic contrast-enhanced dual energy spectral scans in the hepatic arterial, portal venous, and equilibrium phases. The tri-phasic spectral CT images were used to obtain three groups of VNC images including in the arterial (VNCa), venous (VNCv), and equilibrium (VNCe) phase by the material decomposition process using water and iodine as a base material pair. The image quality and the contrast-to-noise ratio (CNR) of metastasis of the four groups were compared with ANOVA analysis. The metastasis detection rates with the four nonenhanced image groups were calculated and compared using the Chi-square test. There were no significant differences in image quality among TNC, VNCa and VNCv images (P > 0.05). The quality of VNCe images was significantly worse than that of other three groups (P 0.05). The metastasis detection rate of the four nonenhanced groups with no statistically significant difference (P > 0.05). The quality of VNCa and VNCv images is identical to that of TNC images, and the metastasis detection rate in VNC images is similar to that in TNC images. VNC images obtained from arterial phase show metastases more clearly. Thus, VNCa imaging may be a surrogate to TNC imaging in hepatic metastasis diagnosis.

  19. Application of Computed Tomography Virtual Noncontrast Spectral Imaging in Evaluation of Hepatic Metastases: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Shi-Feng Tian

    2015-01-01

    Full Text Available Objective: The objective was to qualitatively and quantitatively evaluate hepatic metastases using computed tomography (CT virtual noncontrast (VNC spectral imaging in a retrospective analysis. Methods: Forty hepatic metastases patients underwent CT scans including the conventional true noncontrast (TNC and the tri-phasic contrast-enhanced dual energy spectral scans in the hepatic arterial, portal venous, and equilibrium phases. The tri-phasic spectral CT images were used to obtain three groups of VNC images including in the arterial (VNCa, venous (VNCv, and equilibrium (VNCe phase by the material decomposition process using water and iodine as a base material pair. The image quality and the contrast-to-noise ratio (CNR of metastasis of the four groups were compared with ANOVA analysis. The metastasis detection rates with the four nonenhanced image groups were calculated and compared using the Chi-square test. Results: There were no significant differences in image quality among TNC, VNCa and VNCv images (P > 0.05. The quality of VNCe images was significantly worse than that of other three groups (P 0.05. The metastasis detection rate of the four nonenhanced groups with no statistically significant difference (P > 0.05. Conclusions: The quality of VNCa and VNCv images is identical to that of TNC images, and the metastasis detection rate in VNC images is similar to that in TNC images. VNC images obtained from arterial phase show metastases more clearly. Thus, VNCa imaging may be a surrogate to TNC imaging in hepatic metastasis diagnosis.

  20. Exploring Global Change In Place-Based Case Studies

    Science.gov (United States)

    Moosavi, S. C.

    2011-12-01

    The complexity of global climate change makes the subject challenging for the average student, particularly given the nuanced feedbacks and exceptions to the general "warming" or "drying" trend that may be experienced at the local and regional level at which most people experience geologic processes. Geoscience educators can reduce these barriers and draw in student learners by adopting a place-based approach to teaching and researching geologic principles that relate to global change. Assisting students in recognizing and understanding the geologic environment in which they live and study has the side benefit of making the potential effect of climate change tangible. This presentation will review several approaches for using place-based case studies to explore global climate change issues in large lecture, small seminar, field research and service learning environments. The special place project used in large introductory physical geology courses requires each student to select a place familiar and unique to them for an in depth study of the common course content as the semester progresses. Students are specifically tasked with identifying how their site came to be, the geologic processes that act upon it today, how the site may have been different during the last glacial advance and how global climate change (specifically warming of 3OC over 50 years) might impact the site. The concept that change has occurred at the student's site in the past, even far from glacial environments, opens students to the scale of potential anthropogenic climate change. A freshman seminar Global Warming & Climate Change - Service in Preparation for Climate Change: The Second Battle of New Orleans focused on the environmental threats to New Orleans and southeastern Louisiana resulting from regional land use decisions in the centuries before Hurricane Katrina, and the threat that global change relating to sea level rise, acceleration of the hydrologic cycle and intensification of

  1. Global study of nuclear modifications on parton distribution functions

    Directory of Open Access Journals (Sweden)

    Rong Wang

    2017-07-01

    Full Text Available A global analysis of nuclear medium modifications of parton distributions is presented using deeply inelastic scattering data of various nuclear targets. Two obtained data sets are provided for quark and gluon nuclear modification factors, referred as nIMParton16. One is from the global fit only to the experimental data of isospin-scalar nuclei (Set A, and the other is from the fit to all the measured nuclear data (Set B. The scale-dependence is described by DGLAP equations with nonlinear corrections in this work. The Fermi motion and off-shell effect, nucleon swelling, and parton–parton recombination are taken into account together for modeling the complicated x-dependence of nuclear modification. The nuclear gluon shadowing in this paper is dynamically generated by the QCD evolution of parton splitting and recombination processes with zero gluon density at the input scale. Sophisticated nuclear dependence of nuclear medium effects is studied with only two free parameters. With the obtained free parameters from the global analysis, the nuclear modifications of parton distribution functions of unmeasured nuclei can be predicted in our model. Nuclear modification of deuteron is also predicted and shown with recent measurement at JLab.

  2. Structural Design Feasibility Study for the Global Climate Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lewin,K.F.; Nagy, J.

    2008-12-01

    Neon, Inc. is proposing to establish a Global Change Experiment (GCE) Facility to increase our understanding of how ecological systems differ in their vulnerability to changes in climate and other relevant global change drivers, as well as provide the mechanistic basis for forecasting ecological change in the future. The experimental design was initially envisioned to consist of two complementary components; (A) a multi-factor experiment manipulating CO{sub 2}, temperature and water availability and (B) a water balance experiment. As the design analysis and cost estimates progressed, it became clear that (1) the technical difficulties of obtaining tight temperature control and maintaining elevated atmospheric carbon dioxide levels within an enclosure were greater than had been expected and (2) the envisioned study would not fit into the expected budget envelope if this was done in a partially or completely enclosed structure. After discussions between NEON management, the GCE science team, and Keith Lewin, NEON, Inc. requested Keith Lewin to expand the scope of this design study to include open-field exposure systems. In order to develop the GCE design to the point where it can be presented within a proposal for funding, a feasibility study of climate manipulation structures must be conducted to determine design approaches and rough cost estimates, and to identify advantages and disadvantages of these approaches including the associated experimental artifacts. NEON, Inc requested this design study in order to develop concepts for the climate manipulation structures to support the NEON Global Climate Experiment. This study summarizes the design concepts considered for constructing and operating the GCE Facility and their associated construction, maintenance and operations costs. Comparisons and comments about experimental artifacts, construction challenges and operational uncertainties are provided to assist in selecting the final facility design. The overall goal

  3. Asian Studies/Global Studies: Transcending Area Studies and Social Sciences

    Directory of Open Access Journals (Sweden)

    John Lie

    2012-03-01

    Full Text Available The post–World War II growth of area studies, and Asian studies in particular, posed a serious challenge to the mainstream social sciences. Yet the epistemic and institutional foundations of area studies were never well articulated or justified, and the post–Cold War years brought a pervasive sense of crisis to its intellectual mission and justification. In particular, the author focuses on the tensions, if not contradictions, between social science disciplines and area studies. In advocating a more integrated human science, which depends more on mobile networks of scholars than on fixed fields of discipline-bound professors, the author suggests global studies as a fitting field of inquiry in the age of globalization.

  4. Estimation of spectral kurtosis

    Science.gov (United States)

    Sutawanir

    2017-03-01

    Rolling bearings are the most important elements in rotating machinery. Bearing frequently fall out of service for various reasons: heavy loads, unsuitable lubrications, ineffective sealing. Bearing faults may cause a decrease in performance. Analysis of bearing vibration signals has attracted attention in the field of monitoring and fault diagnosis. Bearing vibration signals give rich information for early detection of bearing failures. Spectral kurtosis, SK, is a parameter in frequency domain indicating how the impulsiveness of a signal varies with frequency. Faults in rolling bearings give rise to a series of short impulse responses as the rolling elements strike faults, SK potentially useful for determining frequency bands dominated by bearing fault signals. SK can provide a measure of the distance of the analyzed bearings from a healthy one. SK provides additional information given by the power spectral density (psd). This paper aims to explore the estimation of spectral kurtosis using short time Fourier transform known as spectrogram. The estimation of SK is similar to the estimation of psd. The estimation falls in model-free estimation and plug-in estimator. Some numerical studies using simulations are discussed to support the methodology. Spectral kurtosis of some stationary signals are analytically obtained and used in simulation study. Kurtosis of time domain has been a popular tool for detecting non-normality. Spectral kurtosis is an extension of kurtosis in frequency domain. The relationship between time domain and frequency domain analysis is establish through power spectrum-autocovariance Fourier transform. Fourier transform is the main tool for estimation in frequency domain. The power spectral density is estimated through periodogram. In this paper, the short time Fourier transform of the spectral kurtosis is reviewed, a bearing fault (inner ring and outer ring) is simulated. The bearing response, power spectrum, and spectral kurtosis are plotted to

  5. Studies on the spectral interference of gadolinium on different analytes in inductively coupled plasma atomic emission spectroscopy

    International Nuclear Information System (INIS)

    Sengupta, Arijit; Thulasidas, S.K.; Natarajan, V.; Airan, Yougant

    2015-01-01

    Due to the multi-electronic nature, rare earth elements are prone to exhibit spectral interference in ICP-AES, which leads to erroneous determination of analytes in presence of such matrix. This interference is very significant, when the analytes are to be determined at trace level in presence of emission rich matrix elements. An attempt was made to understand the spectral interference of Gd on 29 common analytes like Ag, Al, B, Ba, Bi, Ca, Cd, Ce, Co, Cr, Cu, Dy, Fe, Ga, Gd, In, La, Li, Lu, Mg, Mn, Na, Nd, Ni, Pb, Pr, Sr, Tl and Zn using ICP-AES with capacitive Charged Coupled Device (CCD) as detector. The present study includes identification of suitable interference free analytical lines of these analytes, evaluation of correction factor for each analytical line and determination of tolerance levels of these analytical lines along with the ICP-AES based methodology for simultaneous determination of Gd. Based on the spectral interference study, an ICP-AES based method was developed for the determination of these analytes at trace level in presence of Gd matrix without chemical separation. Further the developed methodology was validated using synthetic samples prepared from commercially available reference material solution of individual element; the results were found to be satisfactory. The method was also compared with other existing techniques

  6. Impact of the spectral and spatial properties of natural light on indoor gas-phase chemistry: Experimental and modeling study.

    Science.gov (United States)

    Blocquet, M; Guo, F; Mendez, M; Ward, M; Coudert, S; Batut, S; Hecquet, C; Blond, N; Fittschen, C; Schoemaecker, C

    2018-05-01

    The characteristics of indoor light (intensity, spectral, spatial distribution) originating from outdoors have been studied using experimental and modeling tools. They are influenced by many parameters such as building location, meteorological conditions, and the type of window. They have a direct impact on indoor air quality through a change in chemical processes by varying the photolysis rates of indoor pollutants. Transmittances of different windows have been measured and exhibit different wavelength cutoffs, thus influencing the potential of different species to be photolysed. The spectral distribution of light entering indoors through the windows was measured under different conditions and was found to be weakly dependent on the time of day for indirect cloudy, direct sunshine, partly cloudy conditions contrary to the light intensity, in agreement with calculations of the transmittance as a function of the zenithal angle and the calculated outdoor spectral distribution. The same conclusion can be drawn concerning the position within the room. The impact of these light characteristics on the indoor chemistry has been studied using the INCA-Indoor model by considering the variation in the photolysis rates of key indoor species. Depending on the conditions, photolysis processes can lead to a significant production of radicals and secondary species. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Shifting Tides in Global Higher Education: Agency, Autonomy, and Governance in the Global Network. Global Studies in Education, Volume 9

    Science.gov (United States)

    Witt, Mary Allison

    2011-01-01

    The increasing connection among higher education institutions worldwide is well documented. What is less understood is how this connectivity is enacted and manifested on specific levels of the global education network. This book details the planning process of a multi-institutional program in engineering between institutions in the US and…

  8. Housing the "Other" Half: American Studies' Global Urban Turn

    Directory of Open Access Journals (Sweden)

    David Faflik

    2010-03-01

    Full Text Available

    Over the course of its short lifetime, the discipline of American studies has utilized a series of self-defining metaphors. With each successive paradigm shift in the field, each of these disciplinary figures, in turn, has been found wanting, and so replaced. American studies’ current, if not consensual, metaphor—the “border”—resembles not a few of its predecessors in that it is spatial in nature and effectively doubles as a figuration of the greater nation. The premise of this paper is that the “border,” like the figures that came before it, has outlived its serviceable purpose for a discipline that continues to evolve.

    This essay proposes the global city, or, more accurately, the global slum, as a post-“border” metaphor peculiarly adapted to the principled transnationalism that now defines American studies for many subscribing students and professionals. On the one hand, the urban has become a prevailing demographic fact in this, the new century. Thus, the multiethnic, multinational world metropolis recommends itself as a more-than-metaphor for the dynamic cultural contact that typifies ascendant hemispheric conceptions of the Americas. On the other hand, the figure of the peripheral city similarly, and spatially, evokes the majority “center” and minority “margin” model of American studies that critics would claim inhibits total global integration among the discipline’s geoculturally diverse practitioners, many of whom reside outside the continental United States. This essay conceptually deploys the world city to explore beyond these professional/territorial “borders.” Its three condensed case studies—first, of Gilded Age Manhattan, second, of the modern Turkish metropolis, and third, of a reunified Germany’s ethnic ghetto—constitute a brisk figurative exercise in “marginal” urban migration, wherein resides an alternate model, and metaphor, of American studies praxis today.

  9. A spectral X-ray CT simulation study for quantitative determination of iron

    Science.gov (United States)

    Su, Ting; Kaftandjian, Valérie; Duvauchelle, Philippe; Zhu, Yuemin

    2018-06-01

    Iron is an essential element in the human body and disorders in iron such as iron deficiency or overload can cause serious diseases. This paper aims to explore the ability of spectral X-ray CT to quantitatively separate iron from calcium and potassium and to investigate the influence of different acquisition parameters on material decomposition performance. We simulated spectral X-ray CT imaging of a PMMA phantom filled with iron, calcium, and potassium solutions at various concentrations (15-200 mg/cc). Different acquisition parameters were considered, such as the number of energy bins (6, 10, 15, 20, 30, 60) and exposure factor per projection (0.025, 0.1, 1, 10, 100 mA s). Based on the simulation data, we investigated the performance of two regularized material decomposition approaches: projection domain method and image domain method. It was found that the former method discriminated iron from calcium, potassium and water in all cases and tended to benefit from lower number of energy bins for lower exposure factor acquisition. The latter method succeeded in iron determination only when the number of energy bins equals 60, and in this case, the contrast-to-noise ratios of the decomposed iron images are higher than those obtained using the projection domain method. The results demonstrate that both methods are able to discriminate and quantify iron from calcium, potassium and water under certain conditions. Their performances vary with the acquisition parameters of spectral CT. One can use one method or the other to benefit better performance according to the data available.

  10. The relation between degree-2160 spectral models of Earth's gravitational and topographic potential: a guide on global correlation measures and their dependency on approximation effects

    Science.gov (United States)

    Hirt, Christian; Rexer, Moritz; Claessens, Sten; Rummel, Reiner

    2017-10-01

    Comparisons between high-degree models of the Earth's topographic and gravitational potential may give insight into the quality and resolution of the source data sets, provide feedback on the modelling techniques and help to better understand the gravity field composition. Degree correlations (cross-correlation coefficients) or reduction rates (quantifying the amount of topographic signal contained in the gravitational potential) are indicators used in a number of contemporary studies. However, depending on the modelling techniques and underlying levels of approximation, the correlation at high degrees may vary significantly, as do the conclusions drawn. The present paper addresses this problem by attempting to provide a guide on global correlation measures with particular emphasis on approximation effects and variants of topographic potential modelling. We investigate and discuss the impact of different effects (e.g., truncation of series expansions of the topographic potential, mass compression, ellipsoidal versus spherical approximation, ellipsoidal harmonic coefficient versus spherical harmonic coefficient (SHC) representation) on correlation measures. Our study demonstrates that the correlation coefficients are realistic only when the model's harmonic coefficients of a given degree are largely independent of the coefficients of other degrees, permitting degree-wise evaluations. This is the case, e.g., when both models are represented in terms of SHCs and spherical approximation (i.e. spherical arrangement of field-generating masses). Alternatively, a representation in ellipsoidal harmonics can be combined with ellipsoidal approximation. The usual ellipsoidal approximation level (i.e. ellipsoidal mass arrangement) is shown to bias correlation coefficients when SHCs are used. Importantly, gravity models from the International Centre for Global Earth Models (ICGEM) are inherently based on this approximation level. A transformation is presented that enables a

  11. PILOT STUDY: Report on the CCPR Pilot Comparison: Spectral Responsivity 10 nm to 20 nm

    Science.gov (United States)

    Scholze, Frank; Vest, Robert; Saito, Terubumi

    2010-01-01

    The CCPR Pilot Comparison on spectral responsivity in the 10 nm to 20 nm spectral range was carried out within the framework of the CIPM Mutual Recognition Arrangement by three laboratories: PTB (Germany), NIST (USA), and NMIJ/AIST (Japan) with PTB acting as the central and reporting laboratory. All participating laboratories used monochromatized synchrotron radiation. PTB and NIST used a cryogenic radiometer as the primary standard detector and NMIJ, an ionization chamber with extrapolation by a wavelength-independent detector. The aim of the pilot comparison was to check the accuracy of the radiometric scale of spectral responsivity in the short wavelength EUV spectral range which has recently gained in technological importance. The wavelengths of measurement were from 11.5 nm to 20 nm in 0.5 nm steps and additionally 12.2 nm. The comparison was carried out through the calibration of a group of transfer standard detectors. Two sets of three diodes of types AXUV and SXUV from International Radiation Detectors, Inc. were used for the comparison. The comparison had the form of a star comparison: Pilot-lab A-pilot-lab B-pilot, PTB acting as the pilot laboratory. All results were communicated directly to the pilot laboratory. The report describes in detail the measurements made at PTB and summarizes the reports submitted by the participants. Measurements carried out by the pilot laboratory before and after the circulation of the detectors proved that the stability of the detectors was sufficient for the comparison. For the type AXUV detectors, however, changes in their responsivity contributed to the uncertainty of the comparison. Measurement results from participants and their associated uncertainties were analyzed in this report according to the Guidelines for CCPR Comparison Report Preparation. The uncertainty contributions were separated, as to whether they are wavelength dependent or not. All bilateral DoE are well within the respective k = 2 expanded uncertainty

  12. TESIS experiment on study of solar corona in EUV spectral range (CORONAS-PHOTON project)

    International Nuclear Information System (INIS)

    Kuzin, S.V.; Zhitnik, I.A.; Ignat'ev, A.P.; Mitrofanov, A.V.; Pertsov, A.A.; Bugaenko, O.I.

    2005-01-01

    A new orbital station, namely: the CORONAS-PHOTON one (to be launched in 2006) equipped with systems to explore Sun at the intensification period of the solar activity 24-th cycle and at its peak is being designed within the framework of the CORONAS National Sun Space Exploration Program. The station equipment consists of systems to observe Sun within the spectral soft X-ray and vacuum ultraviolet bands. Paper lists and describes the TESIS experiment tools designed for the CORONAS-PHOTON Project to ensure the Sun atmospheric research within short-wave band [ru

  13. Reliability Study of Mechatronic Power Components Using Spectral Photon Emission Microscopy

    Directory of Open Access Journals (Sweden)

    N. Moultif

    2016-11-01

    Full Text Available In this paper, we present one of the most important failure analysis tools that permits the localizing and the identification of the failure mechanisms. It is a new spectral photon emission system, enabling to localize the failure, and quickly get the photon emission spectra that characterize the failure with high resolution. A diffraction grating is used as a spectrometer in the system. Application results on mechatronic power devices such as HEMT AlGaN/GAN and SiC MOSFETs are reported.

  14. Language Learning Motivation, Global English and Study Modes: A Comparative Study

    Science.gov (United States)

    Lanvers, Ursula

    2017-01-01

    Exploring the popular explanation that the global spread of English may demotivate students with English as their first language to learn other languages, this study investigates relations between student motivation and perception of Global English and tests for differences between traditional "campus" and distance university students…

  15. Initial clinical experience with dual-layer detector spectral CT in patients with acute intracerebral haemorrhage: A single-centre pilot study.

    Directory of Open Access Journals (Sweden)

    Soo Buem Cho

    Full Text Available The purpose of this study was to investigate the clinical feasibility of spectral analyses using dual-layer detector spectral computed tomography (CT in acute intracerebral haemorrhage (ICH.We retrospectively reviewed patients with acute ICH who underwent CT angiography on a dual-layer detector spectral CT scanner. A spectral data analysis was performed to detect contrast enhancement in or adjacent to acute ICH by using spectral image reconstructions including monoenergetic (MonoE, virtual noncontrast (VNC, and iodine overlay fusion images. We also acquired a spectral plot to assess material differentiation within lesions.Among the 30 patients, the most common cause of acute ICH was chronic hypertension (18/30, 60% followed by trauma (5/30, 16.7%, brain tumour (3/30, 10%, Moyamoya disease (2/30, 6.7%, and haemorrhagic diathesis from anticoagulation therapy (2/30, 6.7%. Of 30 patients, 13 showed suboptimal iodine suppression in the subcalvarial spaces on VNC images compared with true noncontrast images. The CT angiographic spot sign within the acute ICH was detected in four patients (4/30, 13.3%. All three tumours were metastatic and included lung cancer (n = 2 and hepatocellular carcinoma (n = 1 which showed conspicuous delineation of an enhancing tumour portion in the spectral analysis. Spectral analyses allowed the discrimination of acute haemorrhage and iodine with enhanced lesion visualization on the MonoE images obtained at lower keVs (less than 70 keV and spectral plot.Even though the image quality of VNC is perceived to be inferior, it is feasible to evaluate acute ICH in clinical settings using dual-layer detector spectral CT. The MonoE images taken at lower keVs were useful for depicting contrast enhancing lesion, and spectral plot might be helpful for material differentiation in patients with acute ICH.

  16. Initial clinical experience with dual-layer detector spectral CT in patients with acute intracerebral haemorrhage: A single-centre pilot study.

    Science.gov (United States)

    Cho, Soo Buem; Baek, Hye Jin; Ryu, Kyeong Hwa; Moon, Jin Il; Choi, Bo Hwa; Park, Sung Eun; Bae, Kyungsoo; Jeon, Kyung Nyeo; Kim, Dong Wook

    2017-01-01

    The purpose of this study was to investigate the clinical feasibility of spectral analyses using dual-layer detector spectral computed tomography (CT) in acute intracerebral haemorrhage (ICH). We retrospectively reviewed patients with acute ICH who underwent CT angiography on a dual-layer detector spectral CT scanner. A spectral data analysis was performed to detect contrast enhancement in or adjacent to acute ICH by using spectral image reconstructions including monoenergetic (MonoE), virtual noncontrast (VNC), and iodine overlay fusion images. We also acquired a spectral plot to assess material differentiation within lesions. Among the 30 patients, the most common cause of acute ICH was chronic hypertension (18/30, 60%) followed by trauma (5/30, 16.7%), brain tumour (3/30, 10%), Moyamoya disease (2/30, 6.7%), and haemorrhagic diathesis from anticoagulation therapy (2/30, 6.7%). Of 30 patients, 13 showed suboptimal iodine suppression in the subcalvarial spaces on VNC images compared with true noncontrast images. The CT angiographic spot sign within the acute ICH was detected in four patients (4/30, 13.3%). All three tumours were metastatic and included lung cancer (n = 2) and hepatocellular carcinoma (n = 1) which showed conspicuous delineation of an enhancing tumour portion in the spectral analysis. Spectral analyses allowed the discrimination of acute haemorrhage and iodine with enhanced lesion visualization on the MonoE images obtained at lower keVs (less than 70 keV) and spectral plot. Even though the image quality of VNC is perceived to be inferior, it is feasible to evaluate acute ICH in clinical settings using dual-layer detector spectral CT. The MonoE images taken at lower keVs were useful for depicting contrast enhancing lesion, and spectral plot might be helpful for material differentiation in patients with acute ICH.

  17. A variable-tune spatial heterodyne spectrometer for broadband spectral line studies in the visible and near-UV

    Science.gov (United States)

    Dawson, Olivia R.; Harris, Walter M.

    2017-11-01

    Reflective Spatial Heterodyne Spectroscopy (SHS) is an interferometric technique that combines high resolving power and a large input acceptance angle in a format that is compact enough for use at small telescope focal planes and in spacecraft observations of targets in the visible to far ultra-violet (FUV) spectral range. SHS instruments are well suited to the study of faint, extended emission line sources, particularly in the UV where stellar background continuum becomes weak. Their primary limitation comes from the limited spatial sampling of the output interference pattern generated by the incoming spectral source, which limits their use to narrow bandpass near the central tuning wavelength. We describe a the first light results from a broadband SHS that can be used to scan the tuning wavelength across a bandpass extending from 300 to 700 nm. The limitations on the bandpass are arbitrary and can easily be extended into the UV or near infrared. We discuss the results of these validation program and the potential improvements that could be used to expand and/or improve the broadband spectral response of the instrument.

  18. Synthesis and spectral studies of Pd(II) complexes with 2, 3-disubstituted quinazolin-(3H)-4-ones

    International Nuclear Information System (INIS)

    Prabhakar, B.; Lingaiah, P.; Laxima Reddy, K.

    1991-01-01

    A number of palladium(II) complexes of bidentate O-O and O-N donors, 2,3-disubstituted quinazoline-(3H)-4-ones, have been synthesized and characterized based on analytical, conductivity, magnetic, thermal, IR, electronic and PMR spectral data. The complexes of Pd(II) with ligands such as 2-(R)-3-(X)-substituted quinazoline-(3H)-4-ones, where R=methyl/phenyl and X=2'-hydroxybenzalimino (MHBQ/PHBQ), carboxymethyl (MCMQ/PCMQ), furfuralimino (MFQ/PFQ), acetamino (MAQ/PAQ), uramino (MUQ/PUQ) and thiouramino (MTUQ/PTUQ), yielded the complexes of the type [Pd(O-N) 2 ]Cl 2 and [Pd(O-O) 2 ]. The IR and PMR spectral data of the metal complexes indicate that MHQB, PHQB, MCMQ, and PCMQ act as uninegative bidentate ligands whereas MFQ, PFQ, MAQ, PAQ, MUQ, PUQ, MTUQ and PTUQ act as neutral bidentate ligands. The electronic spectral studies of these complexes indicate that they were square-planar geometry. (author). 23 refs., 2 tabs

  19. A study of the temporal and spectral characteristics of gamma ray bursts

    International Nuclear Information System (INIS)

    Norris, J.

    1983-05-01

    Gamma-ray burst data obtained from the ISEE-3 Gamma Ray Burst Spectrometer and the Solar Maximum Mission's Hard X-ray Burst Spectrometer (HXRBS) were analyzed to yield information on burst temporal and spectral characteristics. A Monte Carlo approach was used to simulate the HXRBS response to candidate spectral models. At energies above about 100 keV, the spectra are well fit by exponential forms. At lower energies, 30 keV to 60 keV, depressions below the model continua are apparent in some bursts. The depressions are not instrumental or data-reduction artifacts. The event selection criterion of the ISEE-3 experiment is based on the time to accumulate a present number of photons rather than the photon count per unit time and is consequently independent of event duration for a given burst intensity, unlike most conventional systems. As a result, a significantly greater percentage of fast, narrow events have been detected. The ratio of count rates from two ISEE-3 detectors indicates that bursts with durations or aprox. one second have much softer spectra than longer bursts

  20. Family Medicine Global Health Fellowship Competencies: A Modified Delphi Study.

    Science.gov (United States)

    Rayess, Fadya El; Filip, Anna; Doubeni, Anna; Wilson, Calvin; Haq, Cynthia; Debay, Marc; Anandarajah, Gowri; Heffron, Warren; Jayasekera, Neil; Larson, Paul; Dahlman, Bruce; Valdman, Olga; Hunt, Vince

    2017-02-01

    Many US medical schools and family medicine departments have responded to a growing interest in global health by developing global health fellowships. However, there are no guidelines or consensus statements outlining competencies for global health fellows. Our objective was to develop a mission and core competencies for Family Medicine Global Health Fellowships. A modified Delphi technique was used to develop consensus on fellowship competencies. A panel, comprised of 13 members with dual expertise in global health and medical education, undertook an iterative consensus process, followed by peer review, from April to December 2014. The panel developed a mission statement and identified six domains for family medicine global health fellowships: patient care, medical knowledge, professionalism, communication and leadership, teaching, and scholarship. Each domain includes a set of core and program-specific competencies. The family medicine global health competencies are intended to serve as an educational framework for the design, implementation, and evaluation of individual family medicine global health fellowship programs.

  1. A non-invasive, quantitative study of broadband spectral responses in human visual cortex.

    Directory of Open Access Journals (Sweden)

    Eline R Kupers

    Full Text Available Currently, non-invasive methods for studying the human brain do not routinely and reliably measure spike-rate-dependent signals, independent of responses such as hemodynamic coupling (fMRI and subthreshold neuronal synchrony (oscillations and event-related potentials. In contrast, invasive methods-microelectrode recordings and electrocorticography (ECoG-have recently measured broadband power elevation in field potentials (~50-200 Hz as a proxy for locally averaged spike rates. Here, we sought to detect and quantify stimulus-related broadband responses using magnetoencephalography (MEG. Extracranial measurements like MEG and EEG have multiple global noise sources and relatively low signal-to-noise ratios; moreover high frequency artifacts from eye movements can be confounded with stimulus design and mistaken for signals originating from brain activity. For these reasons, we developed an automated denoising technique that helps reveal the broadband signal of interest. Subjects viewed 12-Hz contrast-reversing patterns in the left, right, or bilateral visual field. Sensor time series were separated into evoked (12-Hz amplitude and broadband components (60-150 Hz. In all subjects, denoised broadband responses were reliably measured in sensors over occipital cortex, even in trials without microsaccades. The broadband pattern was stimulus-dependent, with greater power contralateral to the stimulus. Because we obtain reliable broadband estimates with short experiments (~20 minutes, and with sufficient signal-to-noise to distinguish responses to different stimuli, we conclude that MEG broadband signals, denoised with our method, offer a practical, non-invasive means for characterizing spike-rate-dependent neural activity for addressing scientific questions about human brain function.

  2. Global Wood Pellet Industry and Trade Study 2017

    NARCIS (Netherlands)

    Thrän, D.; Peetz, D.; Schaubach, K.; Mai-Moulin, T.; Junginger, H.M.; Lamers, P.; Visser, L.

    2017-01-01

    The report Global Wood Pellet Industry Market published in 2011 has always been the most downloaded document of IEA Bioenergy Task 40. We have decided to update the report and bring new insights on market trends and trade of the global wood pellets. The global wood pellet market has increased

  3. Vowel Inherent Spectral Change

    CERN Document Server

    Assmann, Peter

    2013-01-01

    It has been traditional in phonetic research to characterize monophthongs using a set of static formant frequencies, i.e., formant frequencies taken from a single time-point in the vowel or averaged over the time-course of the vowel. However, over the last twenty years a growing body of research has demonstrated that, at least for a number of dialects of North American English, vowels which are traditionally described as monophthongs often have substantial spectral change. Vowel Inherent Spectral Change has been observed in speakers’ productions, and has also been found to have a substantial effect on listeners’ perception. In terms of acoustics, the traditional categorical distinction between monophthongs and diphthongs can be replaced by a gradient description of dynamic spectral patterns. This book includes chapters addressing various aspects of vowel inherent spectral change (VISC), including theoretical and experimental studies of the perceptually relevant aspects of VISC, the relationship between ar...

  4. Globalization, Local and Global Identities of Students (Case study: University of Tabriz

    Directory of Open Access Journals (Sweden)

    Akram Hobbi

    2010-06-01

    Full Text Available The process of globalization is both a disputable issue and an ambiguous one and it has been approached through various and sometimes contradictory views. One of the major topics related to the process of globalization is the subject of survival or persistence of local identities in the mainstream of global economy and culture. Different views have been presented in this respect. One of them claims that globalization has a negative influence on local identities, and eliminates the differences. Some others, however, state an opposite view. This paper has identified three fundamental but different approaches and examines them by the research’s data .This research which its subjects are Fars, Turk and Kurd students of Tabriz University, indicates that as the global identity among the students’ increases, their local identities decrease. In other words, with enhancement of globalization process, local identities starts to decrease and it means that second and third approach’s theories in the research is rejected and the first approach’s theories are confirmed.

  5. The feasibility study of BGO crystal applied to natural gamma ray spectral logging in deep wells

    International Nuclear Information System (INIS)

    Li Wen; Zhang Jingyi

    1992-01-01

    The experimental research on the feasibility of BGO crystal application to natural gamma ray spectral logging was performed under laboratory conditions. The natural radioactive standard sources and heater case were used to simulate the realistic logging environment. The experimental results of BGO detector show that the spectrum stabilization can be effectively realized, and the temperature effect of energy resolution has no obvious impact on spectrum analysis when the temperature of detector ranging from 20 degree C to 60 degree C. The temperature effect of the output pulse height is the main cause of the system error in spectrum analysis, which will surely be reduced in realistic logging by the low temperature gradient. The experimental results of CsI(Na) detector support this conclusion. A suggestion for further work is proposed at the end of this paper

  6. The feasibility study of BGO crystal applied to natural gamma ray spectral logging in deep wells

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Li; Jingyi, Zhang [Qinghua Univ., Beijing (China). Dept. of Engineering Physics; Chongfan, He; Jingying, Liao [Shanghai Silicate Institute (China)

    1992-09-01

    The experimental research on the feasibility of BGO crystal application to natural gamma ray spectral logging was performed under laboratory conditions. The natural radioactive standard sources and heater case were used to simulate the realistic logging environment. The experimental results of BGO detector show that the spectrum stabilization can be effectively realized, and the temperature effect of energy resolution has no obvious impact on spectrum analysis when the temperature of detector ranging from 20 degree C to 60 degree C. The temperature effect of the output pulse height is the main cause of the system error in spectrum analysis, which will surely be reduced in realistic logging by the low temperature gradient. The experimental results of CsI(Na) detector support this conclusion. A suggestion for further work is proposed at the end of this paper.

  7. Spectral distribution study of nuclei in 2p-1f shell

    International Nuclear Information System (INIS)

    Haq, R.; Parikh, J.C.

    1975-01-01

    Systematics of nuclei in the beginning of fp-shell are investigated using the spectral distribution method of French. The centroid energies and widths for various distributions are evaluated using the interaction of Kuo with the modification suggested by McGrory et al. The two moment distributions are used to determine ground state energies, fractional occupancy of the single particle orbits for ground states and low lying spectra of various nuclei in this shell. The results are compared with the deformed configuration mixing calculations of Dhar et al. The goodness of Wigner SU(4) symmetry in these nuclei has been investigated. The mixing of various SU(4) representations near the ground state provides a measure of symmetry mixing and the substantial admixture in most of the cases shows that it is badly broken, largely due to the single particle spin orbit coupling. (author)

  8. A numerical study of viscous vortex rings using a spectral method

    Science.gov (United States)

    Stanaway, S. K.; Cantwell, B. J.; Spalart, Philippe R.

    1988-01-01

    Viscous, axisymmetric vortex rings are investigated numerically by solving the incompressible Navier-Stokes equations using a spectral method designed for this type of flow. The results presented are axisymmetric, but the method is developed to be naturally extended to three dimensions. The spectral method relies on divergence-free basis functions. The basis functions are formed in spherical coordinates using Vector Spherical Harmonics in the angular directions, and Jacobi polynomials together with a mapping in the radial direction. Simulations are performed of a single ring over a wide range of Reynolds numbers (Re approximately equal gamma/nu), 0.001 less than or equal to 1000, and of two interacting rings. At large times, regardless of the early history of the vortex ring, it is observed that the flow approaches a Stokes solution that depends only on the total hydrodynamic impulse, which is conserved for all time. At small times, from an infinitely thin ring, the propagation speeds of vortex rings of varying Re are computed and comparisons are made with the asymptotic theory by Saffman. The results are in agreement with the theory; furthermore, the error is found to be smaller than Saffman's own estimate by a factor square root ((nu x t)/R squared) (at least for Re=0). The error also decreases with increasing Re at fixed core-to-ring radius ratio, and appears to be independent of Re as Re approaches infinity). Following a single ring, with Re=500, the vorticity contours indicate shedding of vorticity into the wake and a settling of an initially circular core to a more elliptical shape, similar to Norbury's steady inviscid vortices. Finally, we consider the case of leapfrogging vortex rings with Re=1000. The results show severe straining of the inner vortex core in the first pass and merging of the two cores during the second pass.

  9. Studying the human dimensions of global climate change

    International Nuclear Information System (INIS)

    Berk, R.A.

    1991-01-01

    With recent scientific interest in climate change has come a need to address substantive issues over very long periods of time and over virtually the entire globe. There is also a growing recognition not only of the links between physical and biological systems but also of the key roles played by human activities and institutions in interaction with the physical and biological world. Hence, the study of climate change presents a host of important questions to social scientists, for which they are not fully prepared. The problems inherent in studying the human dimensions of global climate change do not occur in a scientific vacuum. Rather, they are in part created by, and in part reflect, important gaps in scientific understanding of the physical and biological dimensions. To set the stage, therefore, the general nature of these gaps needs to be briefly reviewed

  10. Vision for a Global Registry of Anticipated Public Health Studies

    Science.gov (United States)

    Choi, Bernard C.K.; Frank, John; Mindell, Jennifer S.; Orlova, Anna; Lin, Vivian; Vaillancourt, Alain D.M.G.; Puska, Pekka; Pang, Tikki; Skinner, Harvey A.; Marsh, Marsha; Mokdad, Ali H.; Yu, Shun-Zhang; Lindner, M. Cristina; Sherman, Gregory; Barreto, Sandhi M.; Green, Lawrence W.; Svenson, Lawrence W.; Sainsbury, Peter; Yan, Yongping; Zhang, Zuo-Feng; Zevallos, Juan C.; Ho, Suzanne C.; de Salazar, Ligia M.

    2007-01-01

    In public health, the generation, management, and transfer of knowledge all need major improvement. Problems in generating knowledge include an imbalance in research funding, publication bias, unnecessary studies, adherence to fashion, and undue interest in novel and immediate issues. Impaired generation of knowledge, combined with a dated and inadequate process for managing knowledge and an inefficient system for transferring knowledge, mean a distorted body of evidence available for decisionmaking in public health. This article hopes to stimulate discussion by proposing a Global Registry of Anticipated Public Health Studies. This prospective, comprehensive system for tracking research in public health could help enhance collaboration and improve efficiency. Practical problems must be discussed before such a vision can be further developed. PMID:17413073

  11. Spectrally selective glazings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    Spectrally selective glazing is window glass that permits some portions of the solar spectrum to enter a building while blocking others. This high-performance glazing admits as much daylight as possible while preventing transmission of as much solar heat as possible. By controlling solar heat gains in summer, preventing loss of interior heat in winter, and allowing occupants to reduce electric lighting use by making maximum use of daylight, spectrally selective glazing significantly reduces building energy consumption and peak demand. Because new spectrally selective glazings can have a virtually clear appearance, they admit more daylight and permit much brighter, more open views to the outside while still providing the solar control of the dark, reflective energy-efficient glass of the past. This Federal Technology Alert provides detailed information and procedures for Federal energy managers to consider spectrally selective glazings. The principle of spectrally selective glazings is explained. Benefits related to energy efficiency and other architectural criteria are delineated. Guidelines are provided for appropriate application of spectrally selective glazing, and step-by-step instructions are given for estimating energy savings. Case studies are also presented to illustrate actual costs and energy savings. Current manufacturers, technology users, and references for further reading are included for users who have questions not fully addressed here.

  12. Maternal mortality: a cross-sectional study in global health.

    Science.gov (United States)

    Sajedinejad, Sima; Majdzadeh, Reza; Vedadhir, AbouAli; Tabatabaei, Mahmoud Ghazi; Mohammad, Kazem

    2015-02-12

    Although most of maternal deaths are preventable, maternal mortality reduction programs have not been completely successful. As targeting individuals alone does not seem to be an effective strategy to reduce maternal mortality (Millennium Development Goal 5), the present study sought to reveal the role of many distant macrostructural factors affecting maternal mortality at the global level. After preparing a global dataset, 439 indicators were selected from nearly 1800 indicators based on their relevance and the application of proper inclusion and exclusion criteria. Then Pearson correlation coefficients were computed to assess the relationship between these indicators and maternal mortality. Only indicators with statistically significant correlation more than 0.2, and missing values less than 20% were maintained. Due to the high multicollinearity among the remaining indicators, after missing values analysis and imputation, factor analysis was performed with principal component analysis as the method of extraction. Ten factors were finally extracted and entered into a multiple regression analysis. The findings of this study not only consolidated the results of earlier studies about maternal mortality, but also added new evidence. Education (std. B = -0.442), private sector and trade (std. B = -0.316), and governance (std. B = -0.280) were found to be the most important macrostructural factors associated with maternal mortality. Employment and labor structure, economic policy and debt, agriculture and food production, private sector infrastructure investment, and health finance were also some other critical factors. These distal factors explained about 65% of the variability in maternal mortality between different countries. Decreasing maternal mortality requires dealing with various factors other than individual determinants including political will, reallocation of national resources (especially health resources) in the governmental sector, education

  13. What is global theater? or, What does new media studies have to do with performance studies?

    Directory of Open Access Journals (Sweden)

    Abigail De Kosnik

    2015-03-01

    Full Text Available This piece summarizes some key historical points of connection between new media studies and performance studies, beginning with Marshall McLuhan's concept of telecommunications networks as constitutive of a global theater. In combination with Kurt Lancaster's and Francesca Coppa's theories of fan works as performances, the global theater model can yield new insights into the nature and purpose of Internet fan fiction and fan fiction archives.

  14. Sustaining a Global Social Network: a quasi-experimental study.

    Science.gov (United States)

    Benton, D C; Ferguson, S L

    2017-03-01

    To examine the longer term impact on the social network of participating nurses in the Global Nursing Leadership Institute (GNLI2013) through using differing frequencies of follow-up to assess impact on maintenance of network cohesion. Social network analysis is increasingly been used by nurse researchers, however, studies tend to use single point-in-time descriptive methods. This study utilizes a repeated measures, block group, control-intervention, quasi-experimental design. Twenty-eight nurse leaders, competitively selected through a double-blind peer review process, were allocated to five action learning-based learning groups. Network architecture, measures of cohesion and node degree frequency were all used to assess programme impact. The programme initiated and sustained connections between nurse leaders drawn from a geographically dispersed heterogeneous group. Modest inputs of two to three e-mails over a 6-month period seem sufficient to maintain connectivity as indicated by measures of network density, diameter and path length. Due to the teaching methodology used, the study sample was relatively small and the follow-up data collection took place after a relatively short time. Replication and further cohort data collection would be advantageous. In an era where many policy solutions are being debated and initiated at the global level, action learning leadership development that utilizes new technology follow-up appears to show significant impact and is worthy of wider application. The approach warrants further inquiry and testing as to its longer term effects on nursing's influence on policy formulation and implementation. © 2016 International Council of Nurses.

  15. Spectral and non-spectral interferences in the determination of thallium in environmental materials using electrothermal atomization and vaporization techniques--a case study

    International Nuclear Information System (INIS)

    Vale, Maria Goreti R.; Welz, Bernhard

    2002-01-01

    The literature on the determination of Tl in environmental samples using electrothermal atomization (ETA) and vaporization (ETV) techniques has been reviewed with special attention devoted to potential interferences and their control. Chloride interference, which is due to the formation of the volatile monochloride in the condensed phase, is the most frequently observed problem. Due to its high dissociation energy (88 kcal/mol), TlCl is difficult to dissociate in the gas phase and is easily lost. The best means of controlling this interference in ETA is atomization under isothermal conditions according to the stabilized temperature platform furnace concept, and the use of reduced palladium as a modifier. An alternative approach appears to be the 'fast furnace' concept, wherein both the use of a modifier and the pyrolysis stage are omitted. This concept requires an efficient background correction system, and high-resolution continuum-source atomic absorption spectrometry (HR-CS AAS) appears to offer the best results. This chloride interference can also cause significant problems when ETV techniques are used. Among the spectral interferences found in the determination of thallium are those due to Pd, the most efficient modifier, and Fe, which is frequently found at high concentrations in environmental samples. Both interferences are due to nearby atomic lines, and are observed only when deuterium background correction and relatively high atomization temperatures are used. A more serious spectral interference is that due to the molecular absorption spectrum of SO 2 , which has a maximum around the Tl line and exhibits a pronounced rotational fine structure. HR-CS AAS again showed the best performance in coping with this interference

  16. A Statistical study of the Doppler spectral width of high-latitude ionospheric F-region echoes recorded with SuperDARN coherent HF radars

    Directory of Open Access Journals (Sweden)

    J.-P. Villain

    2002-11-01

    Full Text Available The HF radars of the Super Dual Auroral Radar Network (SuperDARN provide measurements of the E × B drift of ionospheric plasma over extended regions of the high-latitude ionosphere. We have conducted a statistical study of the associated Doppler spectral width of ionospheric F-region echoes. The study has been conducted with all available radars from the Northern Hemisphere for 2 specific periods of time. Period 1 corresponds to the winter months of 1994, while period 2 covers October 1996 to March 1997. The distributions of data points and average spectral width are presented as a function of Magnetic Latitude and Magnetic Local Time. The databases are very consistent and exhibit the same features. The most stringent features are: a region of very high spectral width, collocated with the ionospheric LLBL/cusp/mantle region; an oval shaped region of high spectral width, whose equator-ward boundary matches the poleward limit of the Holzworth and Meng auroral oval. A simulation has been conducted to evaluate the geometrical and instrumental effects on the spectral width. It shows that these effects cannot account for the observed spectral features. It is then concluded that these specific spectral width characteristics are the signature of ionospheric/magnetospheric coupling phenomena.Key words. Ionosphere (auroral ionosphere; ionosphere-magnetosphere interactions; ionospheric irregularities

  17. A Statistical study of the Doppler spectral width of high-latitude ionospheric F-region echoes recorded with SuperDARN coherent HF radars

    Directory of Open Access Journals (Sweden)

    J.-P. Villain

    Full Text Available The HF radars of the Super Dual Auroral Radar Network (SuperDARN provide measurements of the E × B drift of ionospheric plasma over extended regions of the high-latitude ionosphere. We have conducted a statistical study of the associated Doppler spectral width of ionospheric F-region echoes. The study has been conducted with all available radars from the Northern Hemisphere for 2 specific periods of time. Period 1 corresponds to the winter months of 1994, while period 2 covers October 1996 to March 1997. The distributions of data points and average spectral width are presented as a function of Magnetic Latitude and Magnetic Local Time. The databases are very consistent and exhibit the same features. The most stringent features are: a region of very high spectral width, collocated with the ionospheric LLBL/cusp/mantle region; an oval shaped region of high spectral width, whose equator-ward boundary matches the poleward limit of the Holzworth and Meng auroral oval. A simulation has been conducted to evaluate the geometrical and instrumental effects on the spectral width. It shows that these effects cannot account for the observed spectral features. It is then concluded that these specific spectral width characteristics are the signature of ionospheric/magnetospheric coupling phenomena.

    Key words. Ionosphere (auroral ionosphere; ionosphere-magnetosphere interactions; ionospheric irregularities

  18. Transient global amnesia and neurological events: the Framingham Heart Study

    Directory of Open Access Journals (Sweden)

    Jose Rafael Romero

    2013-05-01

    Full Text Available Background/ objective: Transient global amnesia (TGA is a temporary amnestic syndrome characterized by lack of other focal neurological deficits. Cerebrovascular disease, migraine and seizures have been suggested as underlying mechanisms. TGA may be a risk factor for cerebrovascular or other neurological events. We studied the relation of TGA, vascular risk factors, brain magnetic resonance imaging (MRI indices of subclinical ischemia and neurological events in a community-based sample. Design/setting: A total of 12 TGA cases were ascertained using standard criteria by experienced neurologists, and matched to 41 stroke- and seizure-free controls. Vascular risk factors, brain MRI findings, and subsequent cerebrovascular or seizure events were compared in cases and controls. Participants: Framingham Heart Study (FHS original and offspring cohort participants were included.Results: No significant differences between the groups were observed in the prevalence of vascular risk factors, or brain MRI measures. Few incident stroke/transient ischemic attacks (TIA (1 event among the cases and 4 in controls or subsequent seizures occurred in either group. Head CT during the acute event (n=11 and brain MRI (n=7 were negative for acute abnormalities. Electroencephalograms (EEG (n=5 were negative for epileptiform activity. Extracranial vascular studies were negative for significant stenosis in all cases.Conclusions: In our community-based study TGA was not related to traditional vascular risk factors, or cerebrovascular disease. However, our study is limited by small sample size and power, and larger studies are required to exclude an association.

  19. Born Global Firms: A Foreign Trade Related Study on Turkey

    Directory of Open Access Journals (Sweden)

    Aytaç GÖKMEN

    2013-11-01

    Full Text Available With the comprehensive advent in information and communication technologies and worldwide ease of transportation, the volume of international trade and business increased profoundly. Within this process, a Born Global Firm (BGF, right from its initiation, aims at creating competitive advantage by marketing a large volume of its products in various international markets by utilizing technological advances. Therefore, the rational behind the idea of BGF is to become an international firm in a short period of time and making international business affairs core of its business activities. Thus, the aim of this study is to review the concept of BGF theoretically and relate the issue to foreign trade affairs resting on significant sources related to the Turkish case mainly focusing on trade statistics as to review the potential development of BGFs in Turkey.

  20. GLOBAL IMPACT OF SOLAR ENERGY, CASE STUDY - GERMANY

    Directory of Open Access Journals (Sweden)

    Gheorghe Caralicea Marculescu

    2014-02-01

    Full Text Available Renewable energy is a socially and politically defined category of energy sources. Renewable energy is generally defined as energy that comes from resources which are continually replenished on a human timescale such as sunlight, wind, rain, tides, waves and geothermal heat. About 16% of global final energy consumption comes from renewable resources, with 10% of all energy from traditional biomass, mainly used for heating, and 3.4% from hydroelectricity. New renewables (small hydro, modern biomass, wind, solar, geothermal, and biofuels accounted for another 3% and are growing rapidly. This paper seeks is aimed at presenting the impact solar energy could have on a world level given the finitude, reachability and ever increasing prices of fossil fuels. As a case study we will present the solar energy industry in Germany emphasizing the advantages and disadvantages this form of energy has in this country and worldwide.

  1. Study on Global GIS architecture and its key technologies

    Science.gov (United States)

    Cheng, Chengqi; Guan, Li; Lv, Xuefeng

    2010-11-01

    Global GIS (G2IS) is a system, which supports the huge data process and the global direct manipulation on global grid based on spheroid or ellipsoid surface. Based on global subdivision grid (GSG), Global GIS architecture is presented in this paper, taking advantage of computer cluster theory, the space-time integration technology and the virtual reality technology. Global GIS system architecture is composed of five layers, including data storage layer, data representation layer, network and cluster layer, data management layer and data application layer. Thereinto, it is designed that functions of four-level protocol framework and three-layer data management pattern of Global GIS based on organization, management and publication of spatial information in this architecture. Three kinds of core supportive technologies, which are computer cluster theory, the space-time integration technology and the virtual reality technology, and its application pattern in the Global GIS are introduced in detail. The primary ideas of Global GIS in this paper will be an important development tendency of GIS.

  2. Temperature-dependent dielectric function of germanium in the UV–vis spectral range: A first-principles study

    International Nuclear Information System (INIS)

    Yang, J.Y.; Liu, L.H.; Tan, J.Y.

    2014-01-01

    The study of temperature dependence of thermophysical parameter dielectric function is key to understanding thermal radiative transfer in high-temperature environments. Limited by self-radiation and thermal oxidation, however, it is difficult to directly measure the high-temperature dielectric function of solids with present experimental technologies. In this work, we implement two first-principles methods, the ab initio molecular dynamics (AIMD) and density functional perturbation theory (DFPT), to study the temperature dependence of dielectric function of germanium (Ge) in the UV–vis spectral range in order to provide data of high-temperature dielectric function for radiative transfer study in high-temperature environments. Both the two methods successfully predict the temperature dependence of dielectric function of Ge. Moreover, the good agreement between the calculated results of the AIMD approach and experimental data at 825 K enables us to predict the high-temperature dielectric function of Ge with the AIMD method in the UV–vis spectral range. - Highlights: • The temperature dependence of dielectric function of germanium (Ge) is investigated with two first-principles methods. • The temperature effect on dielectric function of Ge is discussed. • The high-temperature dielectric function of Ge is predicted

  3. To Nail a Pudding: Metaphorical Analysis of the Social Studies Education Discourse Community on Globalization

    Science.gov (United States)

    Agbaria, Ayman K.

    2011-01-01

    Despite the abundance of studies on globalization in educational research, globalization is often approached as a monolithic and standardized concept. Focusing on the social studies education in the USA, this study explores how the various metaphors through which globalization is framed embrace particular perspectives on how to conceive and…

  4. Structural and Moessbauer spectral study of the metastable phase Sm(Fe, Co, Ti)10

    International Nuclear Information System (INIS)

    Bessais, L.; Djega-Mariadassou, C.; Koch, E.

    2002-01-01

    We have performed a Moessbauer spectral analysis of nanocrystalline metastable P 6/mmm SmTi(Fe 1-x Co x ) 9 , correlated with structural transformation towards its equilibrium derivative I4/mmm SmTi(Fe 1-x Co x ) 11 . The Rietveld analysis shows that the 3g site is fully occupied, while the 6 l occupation is limited to hexagons surrounding the Fe-Fe dumb-bell pairs 2e. A specific programme for the Wigner-Seitz cell (WSC) calculation of the metastable disordered structure was used. The hyperfine parameter assignment based on the isomer shift correlation with the WSC volumes sequence leads to Co 3g preferential occupation, with Ti location in 6 l sites. The mean hyperfine field increases with Co content in connection with the enhancement of the negative core electron polarization term upon additional Co electron filling. The same trend is observed for each individual site leading to the sequence H HF {2e}≥H HF {6 l }≥H HF {3g}. (author)

  5. Experimental studies of x-ray laser spectral profiles: Observation of gain narrowing and saturation behavior

    International Nuclear Information System (INIS)

    Koch, J.A.; MacGowan, B.J.; Da Silva, L.B.; Matthews, D.L.; Mrowka, S.; Underwood, J.H.; Batson, P.J.

    1992-01-01

    We discuss our recent measurements of the spectral width of the 206.38 Angstrom x-ray laser transition in Ne-like Se. These measurements used a high-resolution grating spectrometer and were performed over a wide range of laser amplifier lengths. The data have enabled us to extrapolate the intrinsic line width and to observe the effects of gain-narrowing and saturation on the line profile. We find an intrinsic width which is 1.4 times the Doppler width, we observe gain-narrowing in intermediate length amplifiers, and we observe no re-broadening in long, saturated amplifiers. These results suggest that collisional line-broadening has a significant effect on the line profile and saturation behavior of this laser. We discuss modeling we have performed in order to simulate the experimental data, and we discuss future experimental and theoretical efforts we believe are necessary in order to understand line broadening and line transfer issues in x-ray laser plasmas

  6. Spectral Analysis of Dynamic PET Studies: A Review of 20 Years of Method Developments and Applications.

    Science.gov (United States)

    Veronese, Mattia; Rizzo, Gaia; Bertoldo, Alessandra; Turkheimer, Federico E

    2016-01-01

    In Positron Emission Tomography (PET), spectral analysis (SA) allows the quantification of dynamic data by relating the radioactivity measured by the scanner in time to the underlying physiological processes of the system under investigation. Among the different approaches for the quantification of PET data, SA is based on the linear solution of the Laplace transform inversion whereas the measured arterial and tissue time-activity curves of a radiotracer are used to calculate the input response function of the tissue. In the recent years SA has been used with a large number of PET tracers in brain and nonbrain applications, demonstrating that it is a very flexible and robust method for PET data analysis. Differently from the most common PET quantification approaches that adopt standard nonlinear estimation of compartmental models or some linear simplifications, SA can be applied without defining any specific model configuration and has demonstrated very good sensitivity to the underlying kinetics. This characteristic makes it useful as an investigative tool especially for the analysis of novel PET tracers. The purpose of this work is to offer an overview of SA, to discuss advantages and limitations of the methodology, and to inform about its applications in the PET field.

  7. Megafans-Some New Perspectives from a Global Study

    Science.gov (United States)

    Wilkinson, M. Justin

    2016-01-01

    A global study of megafans (greater than 100 km long) has revealed their widespread existence on all continents, with almost 200 documented, 93 in Africa where research is most thorough. The largest measures 705 km. Megafans are a major subset of "DFS" (distributive fluvial systems, a category that includes all fan-like features greater than 30 km long). 1. Many researchers now recognize megafans as different from floodplains, small coarse-grained alluvial fans, and deltas. Although smaller architectural elements in megafans are the same as those encountered in floodplains (channel, overbank, etc.), larger architectures differ because of the unconfined setting of megafans, versus the valley-confined setting of floodplains. 2. A length continuum is now documented between steep alluvial fans 10-20 km in length, and fluvial fans 30-50 km long. This implies a continuum of process from end-member alluvial fan processes (e.g. high-energy flows that emplace gravels, debris-flow units) to the relatively fine-grained channel and overbank deposits common to purely fluvial fans. Combinations of these different processes will then occur in many mid-sized fans. 3. The global distribution suggests a prima facie relationship with tectonic environment rather than climatic zones, with local controls being the slope of the formative river and the existence of a basin subsiding below the long profile of the river. But the global population has revealed that most megafans are relict. So it is possible that further research will show relationships to prior climatic regimes. 4. Megafans can have regional importance: e.g., along the east flank of the central Andes, nested megafans total approximately 750,000 km2-and 1.2m km2 if all megafans in S. America are counted. Modern megafan landscapes thus have basinal importance, orders of magnitude greater than alluvial fan bajadas. 5. Because so many aggrading basins are dominated today by DFS, it is claimed that DFS ought to be significant in

  8. TU-CD-207-02: Quantification of Breast Lesion Compositions Using Low-Dose Spectral Mammography: A Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Cho, H; Ding, H; Sennung, D; Kumar, N; Molloi, S [Department of Radiological Sciences, University of California, Irvine, CA (United States)

    2015-06-15

    Purpose: To investigate the feasibility of measuring breast lesion composition with spectral mammography using physical phantoms and bovine tissue. Methods: Phantom images were acquired with a spectral mammography system with a silicon-strip based photon-counting detector. Plastic water and adipose-equivalent phantoms were used to calibrate the system for dual-energy material decomposition. The calibration phantom was constructed in range of 2–8 cm thickness and water densities in the range of 0% to 100%. A non-linear rational fitting function was used to calibrate the imaging system. The phantom studies were performed with uniform background phantom and non-uniform background phantom. The breast lesion phantoms (2 cm in diameter and 0.5 cm in thickness) were made with water densities ranging from 0 to 100%. The lesion phantoms were placed in different positions and depths on the phantoms to investigate the accuracy of the measurement under various conditions. The plastic water content of the lesion was measured by subtracting the total decomposed plastic water signal from a surrounding 2.5 mm thick border outside the lesion. In addition, bovine tissue samples composed of 80 % lean were imaged as background for the simulated lesion phantoms. Results: The thickness of measured and known water contents was compared. The rootmean-square (RMS) errors in water thickness measurements were 0.01 cm for the uniform background phantom, 0.04 cm for non-uniform background phantom, and 0.03 cm for 80% lean bovine tissue background. Conclusion: The results indicate that the proposed technique using spectral mammography can be used to accurately characterize breast lesion compositions.

  9. Power spectral analysis of the sleep electroencephalogram in heartburn patients with or without gastroesophageal reflux disease: a feasibility study.

    Science.gov (United States)

    Budhiraja, Rohit; Quan, Stuart F; Punjabi, Naresh M; Drake, Christopher L; Dickman, Ram; Fass, Ronnie

    2010-02-01

    Determine the feasibility of using power spectrum of the sleep electroencephalogram (EEG) as a more sensitive tool than sleep architecture to evaluate the relationship between gastroesophageal reflux disease (GERD) and sleep. GERD has been shown to adversely affect subjective sleep reports but not necessarily objective sleep parameters. Data were prospectively collected from symptomatic patients with heartburn. All symptomatic patients underwent upper endoscopy. Patients without erosive esophagitis underwent pH testing. Sleep was polygraphically recorded in the laboratory. Spectral analysis was performed to determine the power spectrum in 4 bandwidths: delta (0.8 to 4.0 Hz), theta (4.1 to 8.0 Hz), alpha (8.1 to 13.0 Hz), and beta (13.1 to 20.0 Hz). Eleven heartburn patients were included in the GERD group (erosive esophagitis) and 6 heartburn patients in the functional heartburn group (negative endoscopy, pH test, response to proton pump inhibitors). The GERD patients had evidence of lower average delta-power than functional heartburn patients. Patients with GERD had greater overall alpha-power in the latter half of the night (3 hours after sleep onset) than functional heartburn patients. No significant differences were noted in conventional sleep stage summaries between the 2 groups. Among heartburn patients with GERD, EEG spectral power during sleep is shifted towards higher frequencies compared with heartburn patients without GERD despite similar sleep architecture. This feasibility study demonstrated that EEG spectral power during sleep might be the preferred tool to provide an objective analysis about the effect of GERD on sleep.

  10. Feasibility and accuracy of dual-layer spectral detector computed tomography for quantification of gadolinium: a phantom study.

    Science.gov (United States)

    van Hamersvelt, Robbert W; Willemink, Martin J; de Jong, Pim A; Milles, Julien; Vlassenbroek, Alain; Schilham, Arnold M R; Leiner, Tim

    2017-09-01

    The aim of this study was to evaluate the feasibility and accuracy of dual-layer spectral detector CT (SDCT) for the quantification of clinically encountered gadolinium concentrations. The cardiac chamber of an anthropomorphic thoracic phantom was equipped with 14 tubular inserts containing different gadolinium concentrations, ranging from 0 to 26.3 mg/mL (0.0, 0.1, 0.2, 0.4, 0.5, 1.0, 2.0, 3.0, 4.0, 5.1, 10.6, 15.7, 20.7 and 26.3 mg/mL). Images were acquired using a novel 64-detector row SDCT system at 120 and 140 kVp. Acquisitions were repeated five times to assess reproducibility. Regions of interest (ROIs) were drawn on three slices per insert. A spectral plot was extracted for every ROI and mean attenuation profiles were fitted to known attenuation profiles of water and pure gadolinium using in-house-developed software to calculate gadolinium concentrations. At both 120 and 140 kVp, excellent correlations between scan repetitions and true and measured gadolinium concentrations were found (R > 0.99, P  0.99, CI 0.99-1.00). Relative mean measurement errors stayed below 10% down to 2.0 mg/mL true gadolinium concentration at 120 kVp and below 5% down to 1.0 mg/mL true gadolinium concentration at 140 kVp. SDCT allows for accurate quantification of gadolinium at both 120 and 140 kVp. Lowest measurement errors were found for 140 kVp acquisitions. • Gadolinium quantification may be useful in patients with contraindication to iodine. • Dual-layer spectral detector CT allows for overall accurate quantification of gadolinium. • Interscan variability of gadolinium quantification using SDCT material decomposition is excellent.

  11. Global Food Security Index Studies and Satellite Information

    Science.gov (United States)

    Medina, T. A.; Ganti-Agrawal, S.; Joshi, D.; Lakhankar, T.

    2017-12-01

    Food yield is equal to the total crop harvest per unit cultivated area. During the elapsed time of germination and frequent harvesting, both human and climate related effects determine a country's' contribution towards global food security. Each country across the globe's annual income per capita was collected to then determine nine countries for further studies. For a location to be chosen, its income per capita needed to be considered poor, uprising or wealthy. Both physical land cover and regional climate helped categorize potential parameters thought to be studied. Once selected, Normalized Difference Vegetation Index (NDVI) data was collected for Ethiopia, Liberia, Indonesia, United States, Norway, Russia, Kuwait and Saudi Arabia over the recent 16 years for approximately every 16 days starting from early in the year 2000. Software languages such as Geographic Information System (GIS), MatLab and Excel were used to determine how population size, income and deforestation directly determines agricultural yields. Because of high maintenance requirements for large harvests when forest areas are cleared, they often have a reduction in soil quality, requiring fertilizer use to produce sufficient crop yields. Total area and vegetation index of each country is to be studied, to determine crop and deforestation percentages. To determine how deforestation impacts future income and crop yield predictions of each country studied. By using NDVI results a parameter is to be potentially found that will help define an index, to create an equation that will determine a country's annual income and ability to provide for their families and themselves.

  12. Space observations for global and regional studies of the biosphere

    Science.gov (United States)

    Cihlar, J.; Li, Z.; Chen, J.; Sellers, P.; Hall, F.

    1994-01-01

    The capability to make space-based measurements of Earth at high spatial and temporal resolutions, which would not otherwise be economically or practically feasible, became available just in time to contribute to scientific understanding of the interactive processes governing the total Earth system. Such understanding has now become essential in order to take practical steps which would counteract or mitigate the pervasive impact of the growing human population on the future habitability of the Earth. The paper reviews the rationale for using space observations for studies of climate and terrestrial ecosystems at global and regional scales, as well as the requirements for such observations for studies of climate and ecosystem dynamics. The present status of these developments is reported along with initiatives under way to advance the use of satellite observations for Earth system studies. The most important contribution of space observations is the provision of physical or biophysical parameters for models representing various components of the Earth system. Examples of such parameters are given for climatic and ecosystem studies.

  13. Global teaching and training initiatives for emerging cohort studies

    Directory of Open Access Journals (Sweden)

    Jessica K. Paulus

    2012-09-01

    Full Text Available A striking disparity exists across the globe, with essentially no large-scale longitudinal studies ongoing in regions that will be significantly affected by the oncoming non-communicable disease epidemic. The successful implementation of cohort studies in most low-resource research environments presents unique challenges that may be aided by coordinated training programs. Leaders of emerging cohort studies attending the First World Cohort Integration Workshop were surveyed about training priorities, unmet needs and potential cross-cohort solutions to these barriers through an electronic pre-workshop questionnaire and focus groups. Cohort studies representing India, Mexico, Nigeria, South Africa, Sweden, Tanzania and Uganda described similar training needs, including on-the-job training, data analysis software instruction, and database and bio-bank management. A lack of funding and protected time for training activities were commonly identified constraints. Proposed solutions include a collaborative cross-cohort teaching platform with web-based content and interactive teaching methods for a range of research personnel. An international network for research mentorship and idea exchange, and modifying the graduate thesis structure were also identified as key initiatives. Cross-cohort integrated educational initiatives will efficiently meet shared needs, catalyze the development of emerging cohorts, speed closure of the global disparity in cohort research, and may fortify scientific capacity development in low-resource settings.

  14. Vital Interests: Cultivating Global Competence in the International Studies Classroom

    Science.gov (United States)

    Johnson, Paula R.; Boyer, Mark A.; Brown, Scott W.

    2011-01-01

    Are students being prepared for the challenges they will face in a globalising world? We investigated whether middle school students were interested in global issues, had knowledge of global issues and possessed the skills needed for competence as a citizen in a globalising world in the context of participating in a five-week, web-based…

  15. Globalization and Academic's Workplace Learning: A Case Study in China

    Science.gov (United States)

    Wang, Xuhong; Seddon, Terri

    2014-01-01

    Globalization is the major confronting challenge of higher education worldwide. And internationalization has become a response of higher education to meet the demands and challenges of globalization. In the recent decades, Chinese government has developed different policies to steer education reforms in order to achieve the aim of…

  16. Adoption of Technology as a Response Strategy to Globalization: A Study of Manufacturing Firms in Kenya

    OpenAIRE

    Solomon Kinyanjui; Margaret A. Oloko; Hazel G. Gachunga; Beatrice G. Gathondu

    2014-01-01

    Globalization affects local and international firms in many ways. Studies have shown that factors in the internal as well as external environments of firms influence the rate to which globalization will affect them. On the local scene however, no known studies have been done on the response of manufacturing firms to counter globalization. In addition, since the concept of globalization is multidimensional and its influence is varied in nature, this study aimed at investigating how manufacturi...

  17. Shape of argon spectral lines emitted from an electric arc (P=760 Torr). Study and application of pressure broadening

    International Nuclear Information System (INIS)

    Kretzas, Dimitrios.

    1978-01-01

    We have studied the broadening and shift of argon spectral lines corresponding to 3p 5 5p-3p 5 4s and 3p 5 4p-3p 5 4s transitions emitted from an electric arc burning under atmospheric pressure. We have revealed the broadening due to neutral atoms pressure effect, distinguishing the transitions whose lower level is a metastable one (1s 3 and 1s 5 ) or a level of strong (1s 2 ) or feeble resonance (1s 4 ). In this study we have employed a mixture of argon (98%) and hydrogen (2%); hydrogen's feeble proportion does not perturb much the discharge and is very suitable for the measure of the electronic density. The important departure of L.T.E. has guided us to imagine and apply an original method to measure the temperature and the overpopulation of the neutral atoms in the fondamental state. Our method which is independent of the existence of L.T.E. is based on the different behavior of the spectral lines which are under the influence of the resonance or Van der Waals broadening. The measure of the broadening constants which in the resonance case are independent of the temperature and vary as Tsup(0,3) for V.d.W's broadening, give us a suitable tool to measure the density and the temperature of the neutral atoms [fr

  18. Transition metal complexes of a new 15-membered [N5] penta-azamacrocyclic ligand with their spectral and anticancer studies

    Science.gov (United States)

    El-Boraey, Hanaa A.; Serag El-Din, Azza A.

    2014-11-01

    Novel penta-azamacrocyclic 15-membered [N5] ligand [L] i.e. 1,5,8,12-tetetraaza-3,4: 9,10-dibenzo-6-ethyl-7-methyl-1,12-(2,6-pyrido)cyclopentadecan-5,7 diene-2,11-dione and its transition metal complexes with Co(II), Ni(II), Cu(II), Ru(III) and Pd(II) have been synthesized and structurally characterized by elemental analysis, spectral, thermal as well as magnetic and molar conductivity measurements. On basis of IR, MS, UV-Vis 1H NMR and EPR spectral studies an octahedral geometry has been proposed for all complexes except Co(II), Cu(II) nitrate complexes and Pd(II) chloride complex that adopt tetrahedral, square pyramidal and square planar geometries, respectively. The antitumor activity of the synthesized ligand and some complexes against human breast cancer cell lines (MCF-7) and human hepatocarcinoma cell lines (HepG2) has been studied. The complexes (IC50 = 2.04-9.7, 2.5-3.7 μg/mL) showed potent antitumor activity comparable with their ligand (IC50 = 11.7, 3.45 μg/mL) against the above mentioned cell lines, respectively. The results evidently show that the activity of the ligand becomes more pronounced and significant when coordinated to the metal ion.

  19. Evidence of across-channel processing for spectral-ripple discrimination in cochlear implant listeners a

    Science.gov (United States)

    Ho Won, Jong; Jones, Gary L.; Drennan, Ward R.; Jameyson, Elyse M.; Rubinstein, Jay T.

    2011-01-01

    Spectral-ripple discrimination has been used widely for psychoacoustical studies in normal-hearing, hearing-impaired, and cochlear implant listeners. The present study investigated the perceptual mechanism for spectral-ripple discrimination in cochlear implant listeners. The main goal of this study was to determine whether cochlear implant listeners use a local intensity cue or global spectral shape for spectral-ripple discrimination. The effect of electrode separation on spectral-ripple discrimination was also evaluated. Results showed that it is highly unlikely that cochlear implant listeners depend on a local intensity cue for spectral-ripple discrimination. A phenomenological model of spectral-ripple discrimination, as an “ideal observer,” showed that a perceptual mechanism based on discrimination of a single intensity difference cannot account for performance of cochlear implant listeners. Spectral modulation depth and electrode separation were found to significantly affect spectral-ripple discrimination. The evidence supports the hypothesis that spectral-ripple discrimination involves integrating information from multiple channels. PMID:21973363

  20. Evidence of across-channel processing for spectral-ripple discrimination in cochlear implant listeners.

    Science.gov (United States)

    Won, Jong Ho; Jones, Gary L; Drennan, Ward R; Jameyson, Elyse M; Rubinstein, Jay T

    2011-10-01

    Spectral-ripple discrimination has been used widely for psychoacoustical studies in normal-hearing, hearing-impaired, and cochlear implant listeners. The present study investigated the perceptual mechanism for spectral-ripple discrimination in cochlear implant listeners. The main goal of this study was to determine whether cochlear implant listeners use a local intensity cue or global spectral shape for spectral-ripple discrimination. The effect of electrode separation on spectral-ripple discrimination was also evaluated. Results showed that it is highly unlikely that cochlear implant listeners depend on a local intensity cue for spectral-ripple discrimination. A phenomenological model of spectral-ripple discrimination, as an "ideal observer," showed that a perceptual mechanism based on discrimination of a single intensity difference cannot account for performance of cochlear implant listeners. Spectral modulation depth and electrode separation were found to significantly affect spectral-ripple discrimination. The evidence supports the hypothesis that spectral-ripple discrimination involves integrating information from multiple channels. © 2011 Acoustical Society of America

  1. Bridging the spectral divide: a case study with PAGES2k, the CESM Last Millennium Ensemble and proxy system models

    Science.gov (United States)

    Zhu, F.; Emile-Geay, J.; Ault, T.; McKay, N.; Dee, S.

    2017-12-01

    A grand challenge for paleoclimatology is to constrain climate model behavior on timescales longer than the instrumental record. Of particular interest is the spectrum of temperature as sensed by climate proxies. The "continuum" of climate variability [Huybers & Curry, Nature 2006] is often characterized by its scaling exponent β , where the spectral density S and the frequency f satisfy the power law S ∝ f-β . Recent studies have voiced concern that climate models underestimate scaling behavior compared to proxies [Laepple & Huybers, PNAS 2014]. Part of this discrepancy is known to lie in the complex processes whereby proxies transform climate signals [Dee et al, EPSL in press], yet many questions remain open. Here we leverage a recent multiproxy compilation [PAGES 2k Consortium, Sci Data 2017] to characterize scaling behavior over the Common Era using an interpolation-free method [Kirchner & Neal, PNAS 2013]. Proxy spectra are compared to spectra derived from the CESM Last Millennium Ensemble [Otto-Bliesner et al, BAMS 2016], using: (a) a naive model where proxies are assumed linearly related to annual temperature vs (b) proxy system models [Evans et al, QSR 2013] of varying complexity. Scaling behavior varies considerably by archive: on average the strongest centennial slopes are observed for lake sediments (β =1.2), while the smallest are observed for glacier ice (β =0.24). Results confirm that the CESM Last Millennium simulation (LM) exhibits decadal-centennial scaling closer to proxy spectra than the pre-industrial control run (PI): the latter shows a "blue" spectrum (β 0), suggesting that forcings are essential to reduce the spectral divide. Yet, even with forcings, LM spectra are flatter than the proxy spectra. Subsequent work will investigate the roles of seasonal sensitivity (trees, foraminifera, alkenones), multivariate influences (corals, trees), detrending (trees) and post-depositional processes (ice cores, lake & marine sediments) on spectral

  2. Study of time dependence and spectral composition of the signal in circuit of ac electric point motors

    Directory of Open Access Journals (Sweden)

    S. Yu. Buryak

    2014-12-01

    Full Text Available Purpose. The paper is aimed to establish the dependence of changes in the time domain and spectral components of the current in the circuit of the AC electric point motor on its technical condition, to identify the common features for the same type of damage. It is necessary using the analysis of the received signals to carry out the remote diagnosis and determination of faults and defects of electric point motors. In addition it suggested to accelerate the process of the failure, malfunction and damage search. Authors propose the automated approach to the service of remote floor automation equipment, which is located in the envelope of trains. Reduction of the threat to life and health of staff by reducing the residence time in the zone of train movement. Reduce the impact of human factors on the result of service. Methodology. The paper studies the structure, parameters and characteristics, the operation and maintenance characteristics of the AC electric point motors. Determination of the main types of possible faults in the process depending on the operating conditions. Presentation of the electric motor as an object of diagnosis. Findings. The time dependences of the current in the circuit of electric point motor for its various states was obtained. The connection between the technical condition of electric point motor and the performance of current curve in time and spectral domains was established. The revealed deviations from the reference signal were justified. According to the obtained results it was made the conclusion. Originality. A method for diagnosing the state of the AC electric point motor by the time dependence and the spectral composition of the current in its circuit was proposed. The connection diagram to the motor windings based on non-infringement of electric parameters of connection circuit in the actual operating conditions was applied. Practical value. The obtained results suggest the possibility and feasibility of

  3. Simulation study of the aerosol information content in OMI spectral reflectance measurements

    Directory of Open Access Journals (Sweden)

    B. Veihelmann

    2007-06-01

    Full Text Available The Ozone Monitoring Instrument (OMI is an imaging UV-VIS solar backscatter spectrometer and is designed and used primarily to retrieve trace gases like O3 and NO2 from the measured Earth reflectance spectrum in the UV-visible (270–500 nm. However, also aerosols are an important science target of OMI. The multi-wavelength algorithm is used to retrieve aerosol parameters from OMI spectral reflectance measurements in up to 20 wavelength bands. A Principal Component Analysis (PCA is performed to quantify the information content of OMI reflectance measurements on aerosols and to assess the capability of the multi-wavelength algorithm to discern various aerosol types. This analysis is applied to synthetic reflectance measurements for desert dust, biomass burning aerosols, and weakly absorbing anthropogenic aerosol with a variety of aerosol optical thicknesses, aerosol layer altitudes, refractive indices and size distributions. The range of aerosol parameters considered covers the natural variability of tropospheric aerosols. This theoretical analysis is performed for a large number of scenarios with various geometries and surface albedo spectra for ocean, soil and vegetation. When the surface albedo spectrum is accurately known and clouds are absent, OMI reflectance measurements have 2 to 4 degrees of freedom that can be attributed to aerosol parameters. This information content depends on the observation geometry and the surface albedo spectrum. An additional wavelength band is evaluated, that comprises the O2-O2 absorption band at a wavelength of 477 nm. It is found that this wavelength band adds significantly more information than any other individual band.

  4. Global Modeling Study of the Bioavailable Atmospheric Iron Supply to the Global Ocean

    Science.gov (United States)

    Myriokefalitakis, S.; Krol, M. C.; van Noije, T.; Le Sager, P.

    2017-12-01

    Atmospheric deposition of trace constituents acts as a nutrient source to the open ocean and affect marine ecosystem. Dust is known as a major source of nutrients to the global ocean, but only a fraction of these nutrients is released in a bioavailable form that can be assimilated by the marine biota. Iron (Fe) is a key micronutrient that significantly modulates gross primary production in the High-Nutrient-Low-Chlorophyll (HNLC) oceans, where macronutrients like nitrate are abundant, but primary production is limited by Fe scarcity. The global atmospheric Fe cycle is here parameterized in the state-of-the-art global Earth System Model EC-Earth. The model takes into account the primary emissions of both insoluble and soluble Fe forms, associated with mineral dust and combustion aerosols. The impact of atmospheric acidity and organic ligands on mineral dissolution processes, is parameterized based on updated experimental and theoretical findings. Model results are also evaluated against available observations. Overall, the link between the labile Fe atmospheric deposition and atmospheric composition changes is here demonstrated and quantified. This work has been financed by the Marie-Curie H2020-MSCA-IF-2015 grant (ID 705652) ODEON (Online DEposition over OceaNs; modeling the effect of air pollution on ocean bio-geochemistry in an Earth System Model).

  5. Spectral properties of nuclear matter

    International Nuclear Information System (INIS)

    Bozek, P

    2006-01-01

    We review self-consistent spectral methods for nuclear matter calculations. The in-medium T-matrix approach is conserving and thermodynamically consistent. It gives both the global and the single-particle properties the system. The T-matrix approximation allows to address the pairing phenomenon in cold nuclear matter. A generalization of nuclear matter calculations to the super.uid phase is discussed and numerical results are presented for this case. The linear response of a correlated system going beyond the Hartree-Fock+ Random-Phase-Approximation (RPA) scheme is studied. The polarization is obtained by solving a consistent Bethe-Salpeter (BS) equation for the coupling of dressed nucleons to an external field. We find that multipair contributions are important for the spin(isospin) response when the interaction is spin(isospin) dependent

  6. Luminescence and Electronic Spectral Studies of Some Synthesized Lanthanide Complexes Using Benzoic Acid Derivative and o-Phenanthroline.

    Science.gov (United States)

    Wankar, Sneha; Limaye, S N

    2015-07-01

    Lanthanide complexes of p-nitrobenzoic acid(p-NBA) and o-phenanthroline(o-phen) namely [Ln2(Phen)2(p-NBA)3(NO3)2].2H2O where, Ln = Sm(III),Tb(III),Dy(III) and [Eu2(Phen)2(p-NBA)3].4H2O were synthesized and further characterized by Elemental analysis, UV spectroscopy, IR spectroscopy, (1)HNMR spectroscopy. Luminescence measurements were performed on all compounds in ethanolic solution. These complexes have showed narrow emission indicating that the organic ligands are better energy absorber and capable of transferring energy to the Ln (III) ion. Furthermore, we reported electronic spectral studies on [Eu2 (Phen)2 (p-NBA)3].4H2O in order to calculate following parameters, viz: Oscillator strength (f), Judd-Ofelt parameters Ωλ (λ = 2,4,6) and Radiative parameters. [Eu2 (o-Phen)2 (p-NBA)3].4H2O showed the strongest emission at 613 nm corresponds to (5)D0→(7)F2 hypersensitive transition, this emission is very sensitive to the environment. However, the larger value of Ω2 supports the presence of the hypersensitive transition (5)D0→(7)F2 which strictly depends on the nature of ligand. All electronic spectral parameters were calculated systemically.

  7. Some new ideas for the study of the complex spectral line profiles of hot emission stars and quasars

    Science.gov (United States)

    Danezis, E.

    2013-01-01

    Some Hot Emission Stars and AGNs present peculiar spectral line profiles which are due to DACs and SACs phenomena. The origin and the mechanisms which are responsible for the creation of DACs/SACs is an important problem that has been studied by many researchers. This paper is a review of our efforts to study the origin and the mechanisms of these phenomena. At first we present a theoretic ad hoc picture for the structure of the plasma that surrounds the specific category of hot emission stars that present DACs or SACs. Then we present the mathematical model that we constructed, which is based on the properties of the above ad hoc theoretical structure. Finally, we present some results from our statistical studies that prove the consistency of our model with the classical physical theory.

  8. Engaging recreational fishers in management and conservation: global case studies.

    Science.gov (United States)

    Granek, E F; Madin, E M P; Brown, M A; Figueira, W; Cameron, D S; Hogan, Z; Kristianson, G; de Villiers, P; Williams, J E; Post, J; Zahn, S; Arlinghaus, R

    2008-10-01

    Globally, the number of recreational fishers is sizeable and increasing in many countries. Associated with this trend is the potential for negative impacts on fish stocks through exploitation or management measures such as stocking and introduction of non-native fishes. Nevertheless, recreational fishers can be instrumental in successful fisheries conservation through active involvement in, or initiation of, conservation projects to reduce both direct and external stressors contributing to fishery declines. Understanding fishers' concerns for sustained access to the resource and developing methods for their meaningful participation can have positive impacts on conservation efforts. We examined a suite of case studies that demonstrate successful involvement of recreational fishers in conservation and management activities that span developed and developing countries, temperate and tropical regions, marine and freshwater systems, and open- and closed-access fisheries. To illustrate potential benefits and challenges of involving recreational fishers in fisheries management and conservation, we examined the socioeconomic and ecological contexts of each case study. We devised a conceptual framework for the engagement of recreational fishers that targets particular types of involvement (enforcement, advocacy, conservation, management design [type and location], research, and monitoring) on the basis of degree of stakeholder stewardship, scale of the fishery, and source of impacts (internal or external). These activities can be enhanced by incorporating local knowledge and traditions, taking advantage of leadership and regional networks, and creating collaborations among various stakeholder groups, scientists, and agencies to maximize the probability of recreational fisher involvement and project success.

  9. SpectralNET – an application for spectral graph analysis and visualization

    Directory of Open Access Journals (Sweden)

    Schreiber Stuart L

    2005-10-01

    Full Text Available Abstract Background Graph theory provides a computational framework for modeling a variety of datasets including those emerging from genomics, proteomics, and chemical genetics. Networks of genes, proteins, small molecules, or other objects of study can be represented as graphs of nodes (vertices and interactions (edges that can carry different weights. SpectralNET is a flexible application for analyzing and visualizing these biological and chemical networks. Results Available both as a standalone .NET executable and as an ASP.NET web application, SpectralNET was designed specifically with the analysis of graph-theoretic metrics in mind, a computational task not easily accessible using currently available applications. Users can choose either to upload a network for analysis using a variety of input formats, or to have SpectralNET generate an idealized random network for comparison to a real-world dataset. Whichever graph-generation method is used, SpectralNET displays detailed information about each connected component of the graph, including graphs of degree distribution, clustering coefficient by degree, and average distance by degree. In addition, extensive information about the selected vertex is shown, including degree, clustering coefficient, various distance metrics, and the corresponding components of the adjacency, Laplacian, and normalized Laplacian eigenvectors. SpectralNET also displays several graph visualizations, including a linear dimensionality reduction for uploaded datasets (Principal Components Analysis and a non-linear dimensionality reduction that provides an elegant view of global graph structure (Laplacian eigenvectors. Conclusion SpectralNET provides an easily accessible means of analyzing graph-theoretic metrics for data modeling and dimensionality reduction. SpectralNET is publicly available as both a .NET application and an ASP.NET web application from http://chembank.broad.harvard.edu/resources/. Source code is

  10. Advancing Collaborative Climate Studies through Globally Distributed Geospatial Analysis

    Science.gov (United States)

    Singh, R.; Percivall, G.

    2009-12-01

    (note: acronym glossary at end of abstract) For scientists to have confidence in the veracity of data sets and computational processes not under their control, operational transparency must be much greater than previously required. Being able to have a universally understood and machine-readable language for describing such things as the completeness of metadata, data provenance and uncertainty, and the discrete computational steps in a complex process take on increased importance. OGC has been involved with technological issues associated with climate change since 2005 when we, along with the IEEE Committee on Earth Observation, began a close working relationship with GEO and GEOSS (http://earthobservations.org). GEO/GEOS provide the technology platform to GCOS who in turn represents the earth observation community to UNFCCC. OGC and IEEE are the organizers of the GEO/GEOSS Architecture Implementation Pilot (see http://www.ogcnetwork.net/AIpilot). This continuing work involves closely working with GOOS (Global Ocean Observing System) and WMO (World Meteorological Organization). This session reports on the findings of recent work within the OGC’s community of software developers and users to apply geospatial web services to the climate studies domain. The value of this work is to evolve OGC web services, moving from data access and query to geo-processing and workflows. Two projects will be described, the GEOSS API-2 and the CCIP. AIP is a task of the GEOSS Architecture and Data Committee. During its duration, two GEO Tasks defined the project: AIP-2 began as GEO Task AR-07-02, to lead the incorporation of contributed components consistent with the GEOSS Architecture using a GEO Web Portal and a Clearinghouse search facility to access services through GEOSS Interoperability Arrangements in support of the GEOSS Societal Benefit Areas. AIP-2 concluded as GEOS Task AR-09-01b, to develop and pilot new process and infrastructure components for the GEOSS Common

  11. A survey of the modern auto- and cross-spectral analyses for the purpose of tokamak study

    International Nuclear Information System (INIS)

    Iwama, N.

    1984-09-01

    The modern techniques of digital auto- and cross-spectral analyses are surveyed for the purpose of the CO 2 -laser scattering experiment on the microinstability and the associated anomalous diffusion in TFR tokamak. The outline of the practical procedures of spectral estimation and the underlying mathematical principles are described with emphasis on the comparison between the maximum entropy method and the conventional methods. The statistical properties of the spectral estimators are discussed and examined by experiments

  12. Study on fusion energy conformity with global environmental issues

    International Nuclear Information System (INIS)

    Kurihara, Kenichi

    1998-01-01

    Global environmental conformity has been one of the most important issues discussed recently as being required for all human activities. From this point of view, this report investigates whether nuclear fusion can be a benign energy source for the global environment. First of all, we chose the following global environmental problems: (1) Global warming, (2) Acid rain, (3) Ozonosphere destruction, (4) Air pollution, (5) Environmental hormones, (6) Radiation and radioactive materials, (7) Electromagnetic waves, and (8) Heat drainage from an energy source. Secondly, these problems were fully surveyed in terms of their relationships with proposed nuclear fusion power plant. Finally, as a result of this discussion, it was confirmed that a fusion power plant would not produce any new problems, but would partially contribute to solving some of the environmental problems. (author)

  13. Global economic consequences of selected surgical diseases: a modelling study.

    Science.gov (United States)

    Alkire, Blake C; Shrime, Mark G; Dare, Anna J; Vincent, Jeffrey R; Meara, John G

    2015-04-27

    The surgical burden of disease is substantial, but little is known about the associated economic consequences. We estimate the global macroeconomic impact of the surgical burden of disease due to injury, neoplasm, digestive diseases, and maternal and neonatal disorders from two distinct economic perspectives. We obtained mortality rate estimates for each disease for the years 2000 and 2010 from the Institute of Health Metrics and Evaluation Global Burden of Disease 2010 study, and estimates of the proportion of the burden of the selected diseases that is surgical from a paper by Shrime and colleagues. We first used the value of lost output (VLO) approach, based on the WHO's Projecting the Economic Cost of Ill-Health (EPIC) model, to project annual market economy losses due to these surgical diseases during 2015-30. EPIC attempts to model how disease affects a country's projected labour force and capital stock, which in turn are related to losses in economic output, or gross domestic product (GDP). We then used the value of lost welfare (VLW) approach, which is conceptually based on the value of a statistical life and is inclusive of non-market losses, to estimate the present value of long-run welfare losses resulting from mortality and short-run welfare losses resulting from morbidity incurred during 2010. Sensitivity analyses were performed for both approaches. During 2015-30, the VLO approach projected that surgical conditions would result in losses of 1·25% of potential GDP, or $20·7 trillion (2010 US$, purchasing power parity) in the 128 countries with data available. When expressed as a proportion of potential GDP, annual GDP losses were greatest in low-income and middle-income countries, with up to a 2·5% loss in output by 2030. When total welfare losses are assessed (VLW), the present value of economic losses is estimated to be equivalent to 17% of 2010 GDP, or $14·5 trillion in the 175 countries assessed with this approach. Neoplasm and injury account

  14. A Global View on Narcolepsy - A Review Study.

    Science.gov (United States)

    Klimova, Blanka; Maresova, Petra; Novotny, Michal; Kuca, Kamil

    2018-02-14

    Narcolepsy is an incurable neurological disorder when the brain is not able to regulate a sleep and wakefulness cycle correctly. The affected person suddenly falls asleep during the day or he/she suffers from excessive day sleepiness. In addition, people may also suffer from cataplexy, hypnagogic hallucinations, sleep paralysis, and disturbed nighttime sleep. The purpose of this review study is to provide the latest information on both clinical and socioeconomic issues in the field of narcolepsy treatment and emphasize its benefits and limitations. The methodological approaches include a method of literature review of available sources exploring the issue of narcolepsy, both from a global and specific perspective point of view. On the basis of evaluation of these literature sources, the researched issue is examined. The main benefits (e.g., new drugs are being tested or non-invasive cognitive behavioral therapies are being applied) and limitations (e.g., late diagnosis of the disease or lifelong and costly treatment) of the treatment of narcolepsy are highlighted. The findings call for more research in the field of the development of novel drugs reflecting understanding of the neurological basis of narcolepsy and early diagnosis in order to eliminate the symptoms of narcolepsy and prevent the development of this disease. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Study of global control of VIRGO Central Interferometer

    International Nuclear Information System (INIS)

    Matone, Luca

    1999-01-01

    The VIRGO project for the detection of gravitational waves will first operate in a test configuration, known as the Central Area Interferometer (CITF). The subject of this thesis consists of a study for the global control of this interferometer. In particular, the problems of auto-alignment and acquisition of lock are addressed. First, an investigation of the CITF optical response to longitudinal and angular mirror movements is given. On the basis of this study, we show how the ratio of photodiode signals can be used to detect and control the dark fringe when the CITF is far from its operating point (locked state). Furthermore, we present the simulation results of a quadrant photodiode configuration capable of reconstructing the mirrors' tilts once the CITF is in a locked state. The performance of a control system for the auto-alignment is then given. A study on the mode-cleaner prototype MC30 is then introduced in order to comprehend the process of lock acquisition by a linear feedback system for two different finesse values: F ≅100 and F ≅ 1600. We define a threshold velocity for the mirrors' relative motion below which acquisition of lock is possible. A phenomenon, referred to as ringing effect, was observed and examined on the MC30 prototype in high finesse. The results of numerical calculations allowed us to fit measurement and estimate from them the cavity finesse as well as the mirrors' relative velocity during the resonance crossing. An empirical formula is then presented capable of determine the relative velocity from the positions of the oscillations' minima and maxima. An algorithm to guide into lock the CITF is then presented, consisting of an iterative procedure of velocity reconstruction and pulse application. A numerical calculation simulated the algorithm, the mirrors' motion, the optical response and the ADCs' process. As a result, acquisition times of the order of one second were observed: an improvement of more than one order of magnitude was

  16. Spectral analysis by correlation

    International Nuclear Information System (INIS)

    Fauque, J.M.; Berthier, D.; Max, J.; Bonnet, G.

    1969-01-01

    The spectral density of a signal, which represents its power distribution along the frequency axis, is a function which is of great importance, finding many uses in all fields concerned with the processing of the signal (process identification, vibrational analysis, etc...). Amongst all the possible methods for calculating this function, the correlation method (correlation function calculation + Fourier transformation) is the most promising, mainly because of its simplicity and of the results it yields. The study carried out here will lead to the construction of an apparatus which, coupled with a correlator, will constitute a set of equipment for spectral analysis in real time covering the frequency range 0 to 5 MHz. (author) [fr

  17. Transmission spectroscopy with the ACE-FTS infrared spectral atlas of Earth: A model validation and feasibility study

    Science.gov (United States)

    Schreier, Franz; Städt, Steffen; Hedelt, Pascal; Godolt, Mareike

    2018-06-01

    Infrared solar occultation measurements are well established for remote sensing of Earth's atmosphere, and the corresponding primary transit spectroscopy has turned out to be valuable for characterization of extrasolar planets. Our objective is an assessment of the detectability of molecular signatures in Earth's transit spectra. To this end, we take a limb sequence of representative cloud-free transmission spectra recorded by the space-borne ACE-FTS Earth observation mission (Hughes et al., ACE infrared spectral atlases of the Earth's atmosphere, JQSRT 2014) and combine these spectra to the effective height of the atmosphere. These data are compared to spectra modeled with an atmospheric radiative transfer line-by-line infrared code to study the impact of individual molecules, spectral resolution, the choice of auxiliary data, and numerical approximations. Moreover, the study serves as a validation of our infrared radiative transfer code. The largest impact is due to water, carbon dioxide, ozone, methane, nitrous oxide, nitrogen, nitric acid, oxygen, and some chlorofluorocarbons (CFC11 and CFC12). The effect of further molecules considered in the modeling is either marginal or absent. The best matching model has a mean residuum of 0.4 km and a maximum difference of 2 km to the measured effective height. For a quantitative estimate of visibility and detectability we consider the maximum change of the residual spectrum, the relative change of the residual norm, the additional transit depth, and signal-to-noise ratios for a JWST setup. In conclusion, our study provides a list of molecules that are relevant for modeling transmission spectra of Earth-like exoplanets and discusses the feasibility of retrieval.

  18. Characterizing CDOM Spectral Variability Across Diverse Regions and Spectral Ranges

    Science.gov (United States)

    Grunert, Brice K.; Mouw, Colleen B.; Ciochetto, Audrey B.

    2018-01-01

    Satellite remote sensing of colored dissolved organic matter (CDOM) has focused on CDOM absorption (aCDOM) at a reference wavelength, as its magnitude provides insight into the underwater light field and large-scale biogeochemical processes. CDOM spectral slope, SCDOM, has been treated as a constant or semiconstant parameter in satellite retrievals of aCDOM despite significant regional and temporal variabilities. SCDOM and other optical metrics provide insights into CDOM composition, processing, food web dynamics, and carbon cycling. To date, much of this work relies on fluorescence techniques or aCDOM in spectral ranges unavailable to current and planned satellite sensors (e.g., global variability in SCDOM and fit deviations in the aCDOM spectra using the recently proposed Gaussian decomposition method. From this, we investigate if global variability in retrieved SCDOM and Gaussian components is significant and regionally distinct. We iteratively decreased the spectral range considered and analyzed the number, location, and magnitude of fitted Gaussian components to understand if a reduced spectral range impacts information obtained within a common spectral window. We compared the fitted slope from the Gaussian decomposition method to absorption-based indices that indicate CDOM composition to determine the ability of satellite-derived slope to inform the analysis and modeling of large-scale biogeochemical processes. Finally, we present implications of the observed variability for remote sensing of CDOM characteristics via SCDOM.

  19. Studies of the spectral and spatial characteristics of shock-induced luminescence from x-cut quartz

    International Nuclear Information System (INIS)

    Brannon, P.J.; Konrad, C.; Morris, R.W.; Jones, E.D.; Asay, J.R.

    1983-01-01

    Spatial and spectral studies of shock-induced luminescence from x-cut crystalline quartz as a function of stress level revealed the following information: Crystalline x-cut quartz has a threshold for emission near the dynamic yield point (about 6 GPa); the spatial distribution of the luminescence from x-cut quartz changes from an intersecting linear emission pattern to a uniform emission pattern as the stress level increases from 6 to 8 GPa; spectra from x-cut quartz are band-like rather than blackbody; crystalline x-cut quartz has emission peaks near 400 and 600 nm; a change in the 400-nm emission with time can be correlated to wave interaction times. A discussion of the luminous emission in terms of yielding and other physical mechanisms is given

  20. Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

    International Nuclear Information System (INIS)

    Vijayaraj, A.; Prabu, R.; Suresh, R.; Narayanan, V.; Sangeetha Kumari, R.; Kaviyarasan, V.

    2012-01-01

    A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base condensation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylenetetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate. All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexes show azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in the cavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexes show irreversible one electron reduction process around -2.15 to -1.60 V. The reduction potential of gadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. The catalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determined. All gadolinium(III) complexes were screened for antibacterial activity

  1. Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Vijayaraj, A.; Prabu, R.; Suresh, R.; Narayanan, V.; Sangeetha Kumari, R.; Kaviyarasan, V. [Univ. of Madras, Madras (India)

    2012-11-15

    A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base condensation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylenetetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate. All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexes show azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in the cavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexes show irreversible one electron reduction process around -2.15 to -1.60 V. The reduction potential of gadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. The catalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determined. All gadolinium(III) complexes were screened for antibacterial activity.

  2. Isolation, NMR Spectral Analysis and Hydrolysis Studies of a Hepta Pyranosyl Diterpene Glycoside from Stevia rebaudiana Bertoni

    Directory of Open Access Journals (Sweden)

    Guohong Mao

    2013-09-01

    Full Text Available From the commercial extract of the leaves of Stevia rebaudiana Bertoni, a minor steviol glycoside, 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyloxy] ent-kaur-16-en-19-oic acid-[(2-O-(3-O-β-D-glucopyranosyl-α-L-rhamnopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl ester] (1; also known as rebaudioside O having seven sugar units has been isolated. Its structural characterization has been achieved by the extensive 1D (1H and 13C, and 2D NMR (COSY, HMQC, HMBC as well as mass spectral data. Further, hydrolysis studies were performed on rebaudioside O using acid and enzymatic methods to identify aglycone and sugar residues in its structure as well as their configurations.

  3. Spectrally resolved hyperfine interactions between polaron and nuclear spins in organic light emitting diodes: Magneto-electroluminescence studies

    Energy Technology Data Exchange (ETDEWEB)

    Crooker, S. A.; Kelley, M. R.; Martinez, N. J. D.; Nie, W.; Mohite, A.; Nayyar, I. H.; Tretiak, S.; Smith, D. L. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Liu, F.; Ruden, P. P. [University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-10-13

    We use spectrally resolved magneto-electroluminescence (EL) measurements to study the energy dependence of hyperfine interactions between polaron and nuclear spins in organic light-emitting diodes. Using layered devices that generate bright exciplex emission, we show that the increase in EL emission intensity I due to small applied magnetic fields of order 100 mT is markedly larger at the high-energy blue end of the EL spectrum (ΔI/I ∼ 11%) than at the low-energy red end (∼4%). Concurrently, the widths of the magneto-EL curves increase monotonically from blue to red, revealing an increasing hyperfine coupling between polarons and nuclei and directly providing insight into the energy-dependent spatial extent and localization of polarons.

  4. Synthesis, Spectral, and In Vitro Antibacterial Studies of Organosilicon(IV) Complexes with Schiff Bases Derived from Amino Acids.

    Science.gov (United States)

    Singh, Har Lal; Singh, Jangbhadur; Mukherjee, A

    2013-01-01

    The present work stems from our interest in the synthesis, characterization, and antibacterial evaluation of organosilicon(IV) complexes of a class of amino-acid-based Schiff base which have been prepared by the interaction of ethoxytrimethylsilane with the Schiff bases (N OH) in 1 : 1 molar ratio. These complexes have been characterized by elemental analysis, molar conductance, and spectroscopic studies including electronic IR and NMR ((1)H, (13)C, and (29)Si) spectroscopy. The analytical and spectral data suggest trigonal bipyramidal geometry around the silicon atom in the resulting complexes. The ligands and their organosilicon complexes have also been evaluated for in vitro antimicrobial activity against bacteria (Bacillus cereus, Nocardia spp., E. aerogenes, Escherichia coli, Klebsiella spp., and Staphylococcus spp.). The complexes were found to be more potent as compared to the ligands.

  5. DFT/TDDFT study on the electronic structure and spectral properties in annulated analogue of phenyl heteroazulene derivative

    International Nuclear Information System (INIS)

    Gasiorski, P.; Danel, K.S.; Matusiewicz, M.; Uchacz, T.; Kuźnik, W.; Piatek, Ł.; Kityk, A.V.

    2012-01-01

    Highlights: ► Cyclic voltammetry study of heteroazulene derivative PTNA. ► DFT/TDDFT/PCM calculations of molecular geometry and electronic states in PTNA. ► TDDFT/PCM calculations of the absorption and fluorescence spectra in PTNA. ► Comparison between TDDFT/PCM calculated and measured optical spectra. - Abstract: Paper reports the DFT/TDDFT study on the electronic structure and spectral properties of the seven-membered annulated heteroazulene derivative 6-phenyl-6H-5,6,7-triazadibenzo[f,h]naphtho[3,2,1-cd]azulene (PTNA) by means of polarizable continuum model (PCM) and Lippert–Mataga–Onsager reaction field (LM-ORF) model at the B3LYP/6-31+G(d,p) level of theory. The results of calculations are compared with the measured optical absorption and fluorescence spectra as well as with the cyclic voltammetry data. The DFT/TDDFT methods exhibit rather good quantitative agreement regarding the spectral position of the first absorption band; the discrepancy between the experiment and theory is less than 0.1 eV. As for the fluorescence emission the TDDFT calculations underestimate the transition energy of about 0.45 eV. The discrepancy should be attributed to insufficient accuracy of the TDDFT optimization in the excited state. In the polar solvent environment, all the TDDFT/PCM approaches give the bathochromic (red) shift for the fluorescence emission and the hypsochromic (blue) shift for the optical absorption in accordance with the experimental observation. As for the fluorescence emission fairly good agreement with the experiment provides the hybrid approach being the combination of the TDDFT/PCM optimization with the semiempirical electronic structure calculations by PM3 method and solvation LM-ORF model predicting the emission energy in different solvents with the accuracy better than 0.06 eV.

  6. Spectral, thermal, kinetic, molecular modeling and eukaryotic DNA degradation studies for a new series of albendazole (HABZ) complexes

    Science.gov (United States)

    El-Metwaly, Nashwa M.; Refat, Moamen S.

    2011-01-01

    This work represents the elaborated investigation for the ligational behavior of the albendazole ligand through its coordination with, Cu(II), Mn(II), Ni(II), Co(II) and Cr(III) ions. Elemental analysis, molar conductance, magnetic moment, spectral studies (IR, UV-Vis and ESR) and thermogravimetric analysis (TG and DTG) have been used to characterize the isolated complexes. A deliberate comparison for the IR spectra reveals that the ligand coordinated with all mentioned metal ions by the same manner as a neutral bidentate through carbonyl of ester moiety and NH groups. The proposed chelation form for such complexes is expected through out the preparation conditions in a relatively acidic medium. The powder XRD study reflects the amorphous nature for the investigated complexes except Mn(II). The conductivity measurements reflect the non-electrolytic feature for all complexes. In comparing with the constants for the magnetic measurements as well as the electronic spectral data, the octahedral structure was proposed strongly for Cr(III) and Ni(II), the tetrahedral for Co(II) and Mn(II) complexes but the square-pyramidal for the Cu(II) one. The thermogravimetric analysis confirms the presence or absence of water molecules by any type of attachments. Also, the kinetic parameters are estimated from DTG and TG curves. ESR spectrum data for Cu(II) solid complex confirms the square-pyramidal state is the most fitted one for the coordinated structure. The albendazole ligand and its complexes are biologically investigated against two bacteria as well as their effective effect on degradation of calf thymus DNA.

  7. The Comparative Study Of Local Governance: Towards A Global Approach The Comparative Study Of Local Governance: Towards A Global Approach

    Directory of Open Access Journals (Sweden)

    Gerry Stoker

    2010-12-01

    Full Text Available The comparative study of local governance has been too focused on the institutional arrangements of the Systems of different nation states rather than the more fundamental issue of the societal functions performed by local government. This article focuses attention on four societal roles that local government systems undertake. They can support political identity, underwrite economic development, facilitate social welfare provision or act as a lifestyle co-ordinator through the practice of community governance. Linking our investigation to the embedded societal roles of local government in different systems opens up the opportunity for a more genuinely global comparative perspective. It also helps us to understand the likely forms of politics associated with different systems of local governance. It also enables us to explore the sustainability of different systems of local governance. It is suggested that a strong system of local government is likely to be one that is able to combine societal roles to a substantial degree. A vulnerable local government system is one trapped with one function that in changing societal and economic circumstances could find itself under threat.El estudio comparado de la gobernanza local se ha focalizado excesivamente en los arreglos institucionales de los sistemas de los diferentes Estados-nación en lugar de centrarse en el tema esencial de las funciones sociales que desempeñan los gobiernos locales. Este artículo centra su atención en cuatro roles sociales que desempeñan los sistemas de gobierno local. Pueden proporcionar identidad política, garantizar el desarrollo económico, facilitar la provisión de servicios sociales o actuar como coordinador de la forma de vida mediante la práctica de la gobernanza comunitaria. La vinculación de la investigación a los roles sociales asumidos por los gobiernos locales en los diferentes sistemas proporciona la posibilidad de adoptar una perspectiva global comparada

  8. Securitization of Migration: an Australian case study of global trends

    Directory of Open Access Journals (Sweden)

    Michael Humphrey

    2014-08-01

    Full Text Available Post September 11 migration has increasingly been framed as a security problem. In the 2010 Australian election campaign migration was connected to security (defense of our borders, terrorism and social cohesion and to related issues of insecurity about the future (population size,sustainability and economic growth. Thisframing of migration as a national security issue overlooks the reality that Australian immigration is part of the global flow of population. Migration is an international issue experienced by states as a national question of border control and sovereignty seeking to manage the consequences of global inequality and mobility. This paper analyses the 'security turn' in migration debates in Australia and the North and the way the securitization of migration signifies the transformation of security from the problem of producing national order to the problem of managing global disorder resulting in the merging of national and international security strategies.

  9. Global, regional, and national incidence and mortality for HIV, tuberculosis, and malaria during 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013

    NARCIS (Netherlands)

    C.J.L. Murray (Christopher); K.F. Ortblad (Katrina F); C. Guinovart (Caterina); S.S. Lim (Stephen); T.M. Wolock (Timothy M); D.A. Roberts (D Allen); E.A. Dansereau (Emily A); N. Graetz (Nicholas); R.M. Barber (Ryan); J.C. Brown (Jonathan C); H. Wang (Haidong); H.C. Duber (Herbert C); M. Naghavi (Morteza); D. Dicker (Daniel); L. Dandona (Lalit); J.A. Salomon (Joshua); K.R. Heuton (Kyle R); K. Foreman (Kyle); D.E. Phillips (David E); T.D. Fleming (Thomas D); A.D. Flaxman (Abraham D); B.K. Phillips (Bryan K); E.M. Johnson (Elizabeth); M.S. Coggeshall (Megan S); F. Abd-Allah (Foad); S.F. Abera (Semaw Ferede); J.P. Abraham (Jerry); I. Abubakar (Ibrahim); L.J. Abu-Raddad (Laith J); N.M. Abu-Rmeileh (Niveen Me); T. Achoki (Tom); A. Adeyemo (Adebowale); A.K. Adou (Arsène Kouablan); J.C. Adsuar (José C); E.E. Agardh (Emilie Elisabet); D. Akena (Dickens); M.J. Al Kahbouri (Mazin J); D. Alasfoor (Deena); M.I. Albittar (Mohammed I); G. Alcalá-Cerra (Gabriel); M.A. Alegretti (Miguel Angel); G. Alemu (Getnet ); R. Alfonso-Cristancho (Rafael); S. Alhabib (Samia); R. Ali (Raghib); F. Alla (Francois); P.J. Allen (Peter); U. Alsharif (Ubai); E. Alvarez (Elena); N. Alvis-Guzman (Nelson); A.A. Amankwaa (Adansi A); A.T. Amare (Azmeraw T); H. Amini (Hassan); K.A. Ammar; B.O. Anderson (Benjamin); C.A.T. Antonio (Carl Abelardo T); P. Anwari (Palwasha); J. Ärnlöv (Johan); V.S.A. Arsenijevic (Valentina S Arsic); A. Artaman (Ali); R.J. Asghar (Rana J); R. Assadi (Reza); L.S. Atkins (Lydia S); A.F. Badawi (Alaa); A. Banerjee (Amitava); S. Basu (Saonli); J. Beardsley (Justin); T. Bekele (Tolesa); M.L. Bell (Michelle Lee); E. Bernabe (Eduardo); T.J. Beyene (Tariku Jibat); N. Bhala (Neeraj); P.L. Bhalla (Pankaj); Z.A. Bhutta (Zulfiqar A); A.B. Abdulhak (Aref Bin); A. Binagwaho (Agnes); J.D. Blore (Jed D); D. Bose (Dipan); M. Brainin (Michael); N. Breitborde (Nicholas); C.A. Castañeda-Orjuela (Carlos A); F. Catalá-López (Ferrán); D. Chadha; J.-C. Chang (Jung-Chen); Y.T. Chiang; T.-W. Chuang (Ting-Wu); M. Colomar (Mercedes); L.T. Cooper Jr. (Leslie Trumbull); C. Cooper (Charles); K.J. Courville (Karen J); M.R. Cowie (Martin R.); M. Criqui (Michael); R. Dandona (Rakhi); A. Dayama (Anand); D. de Leo (Diego); F. Degenhardt; B. Del Pozo-Cruz (Borja); K. Deribe (Kebede); D.C. Des Jarlais (Don C); M. Dessalegn (Muluken); S.D. Dharmaratne (Samath D); U. Dilmen (Uǧur); E.L. Ding (Eric); J.M. Driscoll; Z. Durrani; R.G. Ellenbogen (Richard G); S. Ermakov (Sergey); A. Esteghamati (Alireza); E.J.A. Faraon (Emerito Jose A); F. Farzadfar (Farshad); S.-M. Fereshtehnejad (Seyed-Mohammad); D.O. Fijabi (Daniel Obadare); M.H. Forouzanfar (Mohammad H); U. Fra.Paleo (Urbano); L. Gaffikin (Lynne); A. Gamkrelidze (Amiran); F.G. Gankpé (Fortuné Gbètoho); J.M. Geleijnse (Marianne); B.D. Gessner (Bradford D); K.B. Gibney (Katherine B); I.A.M. Ginawi (Ibrahim Abdelmageem Mohamed); E.L. Glaser (Elizabeth L); P. Gona (Philimon); A. Goto (Akimoto); H.N. Gouda (Hebe N); H.C. Gugnani (Harish Chander); R. Gupta (Rajeev); R. Gupta (Rajeev); N. Hafezi-Nejad (Nima); R.R. Hamadeh (Randah Ribhi); M. Hammami (Mouhanad); G.J. Hankey (Graeme); H.L. Harb (Hilda L); J.M. Haro (Josep Maria); R. Havmoeller (Rasmus); S.I. Hay (Simon I); M.T. Hedayati (Mohammad T); I.B.H. Pi (Ileana B Heredia); H.W. Hoek (Hans); J.C. Hornberger (John C); H.D. Hosgood (H Dean); P.J. Hotez (Peter); D.G. Hoy (Damian G); J. Huang (Jian); K.M. Iburg (Kim M); B.T. Idrisov (Bulat T); K. Innos (Kaire); K.H. Jacobsen (Kathryn H); P. Jeemon (Panniyammakal); P.N. Jensen (Paul N); V. Jha (Vivekanand); G. Jiang (Guohong); J.B. Jonas; K. Juel (Knud); H. Kan (Haidong); I. Kankindi (Ida); V. Karam (Vincent); F. Karch (Francois); C.K. Karema (Corine Kakizi); A. Kaul (Anil); N. Kawakami (Norito); D.S. Kazi (Dhruv S); A.H. Kemp (Andrew H); A.P. Kengne (Andre Pascal); A. Keren (Andre); M. Kereselidze (Maia); Y.S. Khader (Yousef Saleh); S.E.A.H. Khalifa (Shams Eldin Ali Hassan); E.A. Khan (Ejaz Ahmed); Y.-H. Khang (Young-Ho); I. Khonelidze (Irma); Y. Kinfu (Yohannes); J.M. Kinge (Jonas M); L. Knibbs (Luke); Y. Kokubo (Yoshihiro); S. Kosen (Soewarta); B.K. Defo (Barthelemy Kuate); V.S. Kulkarni (Veena S); C. Kulkarni (Chanda); K. Kumar (Kuldeep); R.B. Kumar (Ravi B); G.A. Kumar (G Anil); G.F. Kwan (Gene F); T. Lai (Taavi); A.L. Balaji (Arjun Lakshmana); H. Lam (Hilton); Q. Lan (Qing); V.C. Lansingh (Van C); H.J. Larson (Heidi J); A. Larsson (Anders); J.-T. Lee (Jong-Tae); P.N. Leigh (Nigel); M. Leinsalu (Mall); R. Leung (Ricky); Y. Li (Yichong); Y. Li (Yongmei); G.M.F. de Lima (Graça Maria Ferreira); H.-H. Lin (Hsien-Ho); S.E. Lipshultz (Steven); S. Liu (Simin); Y. Liu (Yang); B.K. Lloyd (Belinda K); P.A. Lotufo (Paulo A); V.M.P. Machado (Vasco Manuel Pedro); J.H. Maclachlan (Jennifer H); C. Magis-Rodriguez (Carlos); M. Majdan (Marek); C.C. Mapoma (Christopher Chabila); W. Marcenes (Wagner); M.B. Marzan (Melvin Barrientos); J.R. Masci (Joseph R); R. Mashal; A.J. Mason-Jones (Amanda J); B.M. Mayosi (Bongani); T.T. Mazorodze (Tasara T); M.J. Mckay (Michael); M.J. Meaney; M.M. Mehndiratta (Man Mohan); F. Mejia-Rodriguez (Fabiola); Y.A. Melaku (Yohannes Adama); Z.A. Memish (Ziad); W. Mendoza (Walter); T.R. Miller (Ted R); E.J. Mills (Edward J); K.A. Mohammad (Karzan Abdulmuhsin); A.H. Mokdad (Ali H); G.L. Mola (Glen Liddell); L. Monasta (Lorenzo); M. Montico (Marcella); A.R. Moore (Ami R); R. Mori (Riccardo); W.N. Moturi (Wilkister Nyaora); M. Mukaigawara (Mitsuru); A.C. Murthy (Adeline C.); A. Naheed (Aliya); K.S. Naidoo (Kovin S); L. Naldi; M. Nangia (Monika); K.M.V. Narayan (Venkat); J.H.E. Nash (John); C. Nejjari (Chakib); R.D. Nelson (Robert); S.P. Neupane (Sudan Prasad); C. Newton (Cameron); M. Ng (Marie); M.I. Nisar (Muhammad Imran); S. Nolte (Sandra); O.F. Norheim (Ole F); V. Nowaseb (Vincent); L. Nyakarahuka (Luke); I.-H. Oh (In-Hwan); T. Ohkubo (Takayoshi); B.O. Olusanya (Bolajoko O); S.B. Omer (Saad B); J.N. Opio (John Nelson); O.E. Orisakwe (Orish Ebere); N.G. Pandian (Natesa); C. Papachristou; M.S. Caicedo (Marco); J. Patten; V.K. Paul (Vinod K); B.I. Pavlin (Boris Igor); N. Pearce (Neil); D.M. Pereira (David M); Z. Pervaiz (Zahid); K. Pesudovs (Konrad); M. Petzold (Max); F. Pourmalek (Farshad); D. Qato (Dima); A.D. Quezada (Amado D); D.A. Quistberg (D Alex); A. Rafay (Anwar); K. Rahimi (Kazem); V. Rahimi-Movaghar (Vafa); S.U. Rahman (Sajjad Ur); M. Raju (Murugesan); S.M. Rana (Saleem M); H. Razavi (Homie); R.Q. Reilly (Robert Quentin); G. Remuzzi (Giuseppe); J.H. Richardus (Jan Hendrik); L. Ronfani (Luca); N. van Roy (Nadine); M.L. Sabin (Miriam Lewis); M.Y. Saeedi (Mohammad Yahya); M.A. Sahraian (Mohammad Ali); G.M.J. Samonte (Genesis May J); M.S. Sawhney (Monika); I.J.C. Schneider (Ione J C); D.C. Schwebel (David C); S. Seedat (Soraya); S.G. Sepanlou (Sadaf G); E.E. Servan-Mori (Edson E); S. Sheikhbahaei (Sara); K. Shibuya (Kenji); H.H. Shin (Hwashin Hyun); I. Shiue (Ivy); R. Shivakoti (Rupak); I.D. Sigfusdottir (Inga Dora); D.H. Silberberg (Donald H); A.P. Silva (Andrea P); J. Simard (Jacques); J.A. Singh (Jasvinder); V. Skirbekk (Vegard); K. Sliwa (Karen); S. Soneji (Samir); S.S. Soshnikov (Sergey S); C.T. Sreeramareddy (Chandrashekhar T); V.K. Stathopoulou (Vasiliki Kalliopi); K. Stroumpoulis (Konstantinos); S. Swaminathan; B.C. Sykes (Bryan); K.M. Tabb (Karen M); R.T. Talongwa (Roberto Tchio); E.Y. Tenkorang (Eric Yeboah); A.S. Terkawi (Abdullah Sulieman); A.J. Thomson (Alan J); A.L. Thorne-Lyman (Andrew L); J.A. Towbin (Jeffrey A); J. Traebert (Jefferson); B.X. Tran (Bach X); Z.T. Dimbuene (Zacharie Tsala); M. Tsilimbaris (Miltiadis); U.S. Uchendu (Uche S); K.N. Ukwaja (Kingsley N); S.R. Vallely (Stephen); T.J. Vasankari (Tommi J); N. Venketasubramanian (Narayanaswamy); F.S. Violante (Francesco S); V.V. Vlassov (Vasiliy Victorovich); P. Waller (Patrick); M.T. Wallin (Mitchell T); L. Wang (Linhong); S.X. Wang; Y. Wang (Yanping); S. Weichenthal (Scott); E. Weiderpass (Elisabete); R.G. Weintraub (Robert G); R. Westerman (Ronny); R.G. White (Richard); J.D. Wilkinson (James D); T.N. Williams (Thomas Neil); S.M. Woldeyohannes (Solomon Meseret); J.B. Wong (John); G. Xu (Gelin); Y.C. Yang (Yang C); K.-I. Yano; P. Yip (Paul); N. Yonemoto (Naohiro); S.-J. Yoon (Seok-Jun); M. Younis (Mustafa); C. Yu (Chuanhua); K.Y. Jin (Kim Yun); M. El Sayed Zaki (Maysaa); Y. Zhao (Yong); Y. Zheng (Yuhui); K. Balakrishnan (Kalpana); M. Zhou (Ming); J. Zhu (Jun); X.N. Zou (Xiao Nong); A.D. Lopez (Alan D); T. Vos (Theo)

    2014-01-01

    markdownabstract__Abstract__ Background: The Millennium Declaration in 2000 brought special global attention to HIV, tuberculosis, and malaria through the formulation of Millennium Development Goal (MDG) 6. The Global Burden of Disease 2013 study provides a consistent and comprehensive approach

  10. Feasibility and accuracy of dual-layer spectral detector computed tomography for quantification of gadolinium: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Hamersvelt, Robbert W. van; Willemink, Martin J.; Jong, Pim A. de; Schilham, Arnold M.R.; Leiner, Tim [University Medical Center Utrecht, Department of Radiology, P.O. Box 85500, Utrecht (Netherlands); Milles, Julien [CT Clinical Science, Philips HealthCare, Best (Netherlands); Vlassenbroek, Alain [CT Clinical Science, Philips HealthCare, Brussels (Belgium)

    2017-09-15

    The aim of this study was to evaluate the feasibility and accuracy of dual-layer spectral detector CT (SDCT) for the quantification of clinically encountered gadolinium concentrations. The cardiac chamber of an anthropomorphic thoracic phantom was equipped with 14 tubular inserts containing different gadolinium concentrations, ranging from 0 to 26.3 mg/mL (0.0, 0.1, 0.2, 0.4, 0.5, 1.0, 2.0, 3.0, 4.0, 5.1, 10.6, 15.7, 20.7 and 26.3 mg/mL). Images were acquired using a novel 64-detector row SDCT system at 120 and 140 kVp. Acquisitions were repeated five times to assess reproducibility. Regions of interest (ROIs) were drawn on three slices per insert. A spectral plot was extracted for every ROI and mean attenuation profiles were fitted to known attenuation profiles of water and pure gadolinium using in-house-developed software to calculate gadolinium concentrations. At both 120 and 140 kVp, excellent correlations between scan repetitions and true and measured gadolinium concentrations were found (R > 0.99, P < 0.001; ICCs > 0.99, CI 0.99-1.00). Relative mean measurement errors stayed below 10% down to 2.0 mg/mL true gadolinium concentration at 120 kVp and below 5% down to 1.0 mg/mL true gadolinium concentration at 140 kVp. SDCT allows for accurate quantification of gadolinium at both 120 and 140 kVp. Lowest measurement errors were found for 140 kVp acquisitions. (orig.)

  11. A numerical study for global atmospheric transport-chemistry problems

    NARCIS (Netherlands)

    E.J. Spee (Edwin); J.G. Verwer (Jan); P.M. de Zeeuw (Paul); J.G. Blom (Joke); W. Hundsdorfer (Willem)

    1998-01-01

    htmlabstractAtmospheric air quality modeling relies in part on numerical simulation. Required numerical simulations are often hampered by lack of computer capacity and computational speed. This problem is most severe in the field of global modeling where transport and exchange of trace constituents

  12. A numerical study for global atmospheric transport-chemistry problems

    NARCIS (Netherlands)

    E.J. Spee (Edwin); J.G. Verwer (Jan); P.M. de Zeeuw (Paul); J.G. Blom (Joke); W. Hundsdorfer (Willem)

    1997-01-01

    textabstractAtmospheric air quality modeling relies in part on numerical simulation. Required numerical simulations are often hampered by lack of computer capacity and computational speed. This problem is most severe in the field of global modeling where transport and exchange of trace constituents

  13. Role of Spectral Studies in Detection of Antibacterial Phytoelements and Phytchemicals of Moringa Oleifera

    NARCIS (Netherlands)

    Mehta, S.; Rai, P.K.; Rai, A.K.; Bicanic, D.D.; Watal, G.

    2011-01-01

    This paper reports, the Laser Induced Breakdown Spectroscopy (LIBS) studies and structure elucidation of compounds isolated from the fruit extract of Moringa oleifera and also deals with their possible effects on some bacterial strains viz. Staphylococcus aureus, Klebsiella pneumonia, Escherichia

  14. OPPORTUNITIES AND RISKS OF GLOBALIZATION IN RURAL AREAS. CASE STUDY: BOTOSANI COUNTY

    Directory of Open Access Journals (Sweden)

    Maria-Simona Cuciureanu

    2014-04-01

    Full Text Available The global economy plays an important role in the development of a region or a county/district as it promotes the exploitation of resources and space in a logical and rational manner. The trend of global economic uniformity allows opportunities and risks to Botoșani County since globalization involves economic development and rising living standards, but loss of cultural values, traditions and customs. The area of study currently confronts with socio-economic and demographic changes that may be addressed by globalization, but at the same time spatial development according to global standards will cause the loss of Botoșani County’s authenticity.

  15. Spectral multitude and spectral dynamics reflect changing conjugation length in single molecules of oligophenylenevinylenes

    KAUST Repository

    Kobayashi, Hiroyuki; Tsuchiya, Kousuke; Ogino, Kenji; Vacha, Martin

    2012-01-01

    Single-molecule study of phenylenevinylene oligomers revealed distinct spectral forms due to different conjugation lengths which are determined by torsional defects. Large spectral jumps between different spectral forms were ascribed to torsional flips of a single phenylene ring. These spectral changes reflect the dynamic nature of electron delocalization in oligophenylenevinylenes and enable estimation of the phenylene torsional barriers. © 2012 The Owner Societies.

  16. Investigations on critical parameters, growth, structural and spectral studies of beta-alaninium picrate (BAP) single crystals

    International Nuclear Information System (INIS)

    Shanthi, D; Selvarajan, P; Perumal, S

    2014-01-01

    Beta-alaninium picrate (BAP) salt has been synthesized and the solubility of the synthesized sample in double distilled water was determined at different temperatures. Solution stability was studied by observing the metastable zone width by employing the polythermal method. Induction period values for different supersaturation ratios at room temperature were determined based on the isothermal method. The nucleation parameters such as critical radius, critical free energy change, interfacial tension, and nucleation rate have been estimated for BAP salt on the basis of the classical nucleation theory. The lattice parameters of the grown BAP crystal were determined using the x-ray diffraction (XRD) technique. The reflection planes of the sample were confirmed by the powder XRD study and diffraction peaks were indexed. Fourier transform infrared spectroscopy and Fourier transform–Raman studies were used to confirm the presence of various functional groups in the BAP crystal. The nonlinear optical property of the grown crystal was studied using the Kurtz–Perry powder technique. UV–visible spectral studies were carried out to understand optical transparency and the type of band gap of the grown BAP crystal. (paper)

  17. Electronic absorption spectral studies of Pr(III) chelates with some amino acids

    Science.gov (United States)

    Kachhawa, Chanchal; Solanki, Kanika; Bhandari, H. S.

    2018-05-01

    Investigations on Pr(III) systems with 1:1 metal-ligand stoichiometric ratio have been carried out in different solvents. β - Alanine, Taurine and anthranilic acid have been opted as ligands for the investigations. The Study is based on doped crystal phenomenon. The Slater-Condon, spin-orbit, nephelauxetic, bonding, Racah and Judd-Ofelt parameters have been explored during the study. Four bands for Pr(III) have been observed and recorded in the region 350 nm to 900nm. Partial regression method has been used for calculations. Use of computational chemistry has been explored in order to develop better and easier methods of calculations.

  18. Spectral Imaging by Upconversion

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Pedersen, Christian; Tidemand-Lichtenberg, Peter

    2011-01-01

    We present a method to obtain spectrally resolved images using upconversion. By this method an image is spectrally shifted from one spectral region to another wavelength. Since the process is spectrally sensitive it allows for a tailored spectral response. We believe this will allow standard...... silicon based cameras designed for visible/near infrared radiation to be used for spectral images in the mid infrared. This can lead to much lower costs for such imaging devices, and a better performance....

  19. Transition metal complexes with oxygen donor ligands: a synthesis, spectral, thermal and antimicrobial study

    Directory of Open Access Journals (Sweden)

    VAIBHAV N. PATANGE

    2008-10-01

    Full Text Available Transition metal complexes of chalcones derived from the conden¬sation of 3-acetyl-6-methyl-2H-pyran-2,4(3H-dione (dehydroacetic acid and p-methoxybenzaldehyde (HL1 or p-nitrobenzaldehyde (HL2 were synthesized and characterized by elemental analysis, conductometry, thermal analysis, magnetic measurements, IR, 1H-NMR, UV–Vis spectroscopy and a microbial study. From the analytical and thermal data, the stoichiometry of the complexes was found to be 1:2 (metal:ligand. The molar conductance data revealed that all the metal chelates were non-electrolytes. The thermal stability of the complexes was studied by thermogravimetry and the decomposition schemes of the complexes are given. The ligands and their metal complexes were screened for antibacterial activity against Staphylococcus aureus and Escherichia coli, and fungicidal activity against Aspergillus flavus, Curvularia lunata and Penicillium notatum.

  20. 1H NMR studies of human lysozyme: Spectral assignment and comparison with hen lysozyme

    International Nuclear Information System (INIS)

    Redfield, C.; Dobson, C.M.

    1990-01-01

    Complete main-chain (NH and αCH) 1 H NMR assignments are reported for the 130 residues of human lysozyme, along with extensive assignments for side-chain protons. Analysis of 2-D NOESY experiments shows that the regions of secondary structure for human lysozyme in solution are essentially identical with those found previously in a similar study of hen lysozyme and are in close accord with the structure of the protein reported previously from x-ray diffraction studies in the crystalline state. Comparison of the chemical shifts, spin-spin coupling constants, and hydrogen exchange behavior are also consistent with closely similar structures for the two proteins in solution. In a number of cases specific differences in the NMR parameters between hen and human lysozymes can be correlated with specific differences observed in the crystal structures

  1. Diabetes induces changes in neuroretina before retinal vessels: a spectral-domain optical coherence tomography study

    OpenAIRE

    Rodrigues, Eduardo B?chele; Urias, M?ller Gon?alves; Penha, Fernando Marcondes; Badar?, Emmerson; Novais, Eduardo; Meirelles, Rodrigo; Farah, Michel Eid

    2015-01-01

    Purpose To investigate retinal changes prior to vascular signs in patients with type 2 diabetes without diabetic retinopathy or with mild non proliferative diabetic retinopathy. Methods A cross-sectional study was performed in three groups: patients without diabetes, patients with type 2 diabetes without diabetic retinopathy, and patients with diabetes with mild diabetic retinopathy. Analysis of retinal layers was performed objectively with the Cirrus Review Software 6.0 (Carl Zeiss Meditec, ...

  2. Oil & Ethnocentrism: A study of Global Oil & Gas Organisations

    OpenAIRE

    Rees, Gareth

    2014-01-01

    This dissertation will examine the concept of ‘ethnocentrism’, or a belief in the superiority of one’s own cultural norms and values, against the backdrop of the Global Oil & Gas Service industry. Using Howard Perlmutter’s framework, ethnocentrism will be tested and analysed across distinct areas of international business; staffing and cultural prevalence, the management of international subsidiaries and corporate and national culture. Data will be collected from experienced Oil & Gas ma...

  3. Effect of Structure on Charge Distribution in the Isatin Anions in Aprotic Environment: Spectral Study

    Directory of Open Access Journals (Sweden)

    Pavol Tisovský

    2017-11-01

    Full Text Available Five isatin anions were prepared by deprotonation of initial isatins in aprotic solvents using basic fluoride and acetate anions (F− and CH3COO−. The F− basicity is sufficient to deprotonate isatin NH hydrogen from all the studied compounds. This process is reversible. In the presence of proton donor solvents, the anions form the corresponding isatins. The isatin hydrogen acidity depends on the overall structure of the isatin derivatives. The anions were characterized by ultraviolet–visible (UV–Vis, Fourier transform infrared (FTIR and nuclear magnetic resonance (NMR spectroscopy. Interestingly, the anions form aggregates at concentrations above 10−3 mol·dm−3. Further, the effect of cations on the UV–Vis spectra of the studied anions was studied. Charge transfer and its distribution in the anion depends on the radius and the cation electron configuration. The alkali metal cations, tetrabutylammonium (TBA+, Mg2+ and Ag+, interact with the C-2 carbonyl oxygen of the isatin anion. The interaction has a coulombic character. On the other hand, Cd2+, Zn2+, Hg2+, Co2+, and Cu+ cations form a coordinate bond with the isatin nitrogen.

  4. Spectral Decomposition Algorithm (SDA)

    Data.gov (United States)

    National Aeronautics and Space Administration — Spectral Decomposition Algorithm (SDA) is an unsupervised feature extraction technique similar to PCA that was developed to better distinguish spectral features in...

  5. Synthesis, magnetic and spectral studies of lanthanide(III) chloride complexes of hydrazones of isonicotinic acid hydrazide

    International Nuclear Information System (INIS)

    Agarwal, R.K.; Agarwal, Himanshu; Prasad, Ram

    1996-01-01

    The synthesis, magnetic and spectral properties of trivalent lanthanide chlorides with N-isonicotinamidobenzalaldimine (INH-BENZ), N-isonicotinamidoanisalaldimine (INH-ANSL) and N-isonicotinamido-p-dimethylaminobenzalaldimine (INH-PDAB) are described. 13 refs., 2 tabs

  6. Spectral methods for study of the G-protein-coupled receptor rhodopsin. II. Magnetic resonance methods

    Science.gov (United States)

    Struts, A. V.; Barmasov, A. V.; Brown, M. F.

    2016-02-01

    This article continues our review of spectroscopic studies of G-protein-coupled receptors. Magnetic resonance methods including electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) provide specific structural and dynamical data for the protein in conjunction with optical methods (vibrational, electronic spectroscopy) as discussed in the accompanying article. An additional advantage is the opportunity to explore the receptor proteins in the natural membrane lipid environment. Solid-state 2H and 13C NMR methods yield information about both the local structure and dynamics of the cofactor bound to the protein and its light-induced changes. Complementary site-directed spin-labeling studies monitor the structural alterations over larger distances and correspondingly longer time scales. A multiscale reaction mechanism describes how local changes of the retinal cofactor unlock the receptor to initiate large-scale conformational changes of rhodopsin. Activation of the G-protein-coupled receptor involves an ensemble of conformational substates within the rhodopsin manifold that characterize the dynamically active receptor.

  7. Study of spectral response of a neutron filter. Design of a method to adjust spectra

    International Nuclear Information System (INIS)

    Colomb-Dolci, F.

    1999-02-01

    The first part of this thesis describes an experimental method which intends to determine a neutron spectrum in the epithermal range [1 eV -10 keV]. Based on measurements of reaction rates provided by activation foils, it gives flux level in each energy range corresponding to each probe. This method can be used in any reactor location or in a neutron beam. It can determine scepter on eight energy groups, five groups in the epithermal range. The second part of this thesis presents a study of an epithermal neutron beam design, in the frame of Neutron Capture Therapy. A beam tube was specially built to test filters made up of different materials. Its geometry was designed to favour epithermal neutron crossing and to cut thermal and fast neutrons. A code scheme was validated to simulate the device response with a Monte Carlo code. Measurements were made at ISIS reactor and experimental spectra were compared to calculated ones. This validated code scheme was used to simulate different materials usable as shields in the tube. A study of these shields is presented at the end of this thesis. (author)

  8. Microenvironmental change as a mechanism to study global change.

    Science.gov (United States)

    Lortie, C. J.

    2016-12-01

    Global change is a set of significant processes that influence all aspects of ecosystem functioning and often-natural services within Santa Barbara County. The sensitivity of coastal and urban systems is certainly very high. However, profound changes are also predicted for arid and semi-arid systems globally, and California is no exception. These dryland systems are less buffered by oceanic processes and typically express high inter-annual variation in precipitation and temperatures in addition to perturbations associated with long-term droughts. However, climate estimates and downscaled values can present challenges in providing evidence at the scale relevant to individual species or individuals, and the importance of biotic interactions must be coupled to these estimates in space and time. Coupled indicators of key micro-environmental measures to both positive and negative interactions between foundation species and other organisms provide a metric of buffering capacity and resilience to global change at fine spatial scales. Consequently, the primary objective of this research project is to provide both the a well-articulated, ecologically relevant micro-environmental big data measure of global change within Santa Barbara County and a coupled estimate of concurrent changes in interactions in key species within the region. Shrubs directly and indirectly buffered local changes in the microenvironment thereby functioning as refuges for other species within arid and semi-arid regions subject to dramatic global change drivers. The following major patterns were identified: (i) shrub micro-environments reduce the level of stress and amplitude of variation associated with temperature and moisture, (ii) many plant and animal species including threatened lizards are relatively more common with shrubs within the region, and (iii) the variation in the interaction patterns between species relates to the extent of amelioration provided by shrub-biodiversity complexes within

  9. Globalization and suicide: an ecological study across five regions of the world.

    Science.gov (United States)

    Milner, Allison; McClure, Rod; De Leo, Diego

    2012-01-01

    The impact of globalization on health is recognized to be influenced by country and regional-level factors. This study aimed to investigate the possible relationship between globalization and suicide in five world regions. An index measure of globalization was developed at the country level over 1980 to 2006. The association between the index and sex specific suicide rates was tested using a fixed-effect regression model. Over time, the globalization index seemed to be associated with increased suicide rates in Asia and the Eastern European/Baltic region. In contrast, it was associated with decreased rates in Scandinavia. There was no significant relationship between globalization and suicide in Southern and Western Europe. The effects of globalization could be determined by specific regional (i.e., cultural and societal) factors. Identification of these mediators might provide opportunities to protect countries from the adverse impacts of globalization.

  10. Spectral methods for study of the G-protein-coupled receptor rhodopsin: I. Vibrational and electronic spectroscopy

    Science.gov (United States)

    Struts, A. V.; Barmasov, A. V.; Brown, M. F.

    2015-05-01

    Here we review the application of modern spectral methods for the study of G-protein-coupled receptors (GPCRs) using rhodopsin as a prototype. Because X-ray analysis gives us immobile snapshots of protein conformations, it is imperative to apply spectroscopic methods for elucidating their function: vibrational (Raman, FTIR), electronic (UV-visible absorption, fluorescence) spectroscopies, and magnetic resonance (electron paramagnetic resonance, EPR), and nuclear magnetic resonance (NMR). In the first of the two companion articles, we discuss the application of optical spectroscopy for studying rhodopsin in a membrane environment. Information is obtained regarding the time-ordered sequence of events in rhodopsin activation. Isomerization of the chromophore and deprotonation of the retinal Schiff base leads to a structural change of the protein involving the motion of helices H5 and H6 in a pH-dependent process. Information is obtained that is unavailable from X-ray crystallography, which can be combined with spectroscopic studies to achieve a more complete understanding of GPCR function.

  11. Spectral dynamics in the B800 band of LH2 from Rhodospirillum molischianum: a single-molecule study

    International Nuclear Information System (INIS)

    Hofmann, Clemens; Aartsma, Thijs J; Michel, Hartmut; Koehler, Juergen

    2004-01-01

    The BChl a absorptions in the B800 spectrum of individual LH2 complexes from Rhodospirillum molischianum show sudden, reversible spectral jumps between a finite number of spectral positions. From our data, we conclude that these fluctuations result from conformational changes of the protein backbone in close vicinity of the chromophores which provides a sensitive tool to monitor local modulations of the pigment-protein interaction

  12. A series of nickel(II complexes derived from hydrazide derivatives, electrochemical, thermal and spectral studies

    Directory of Open Access Journals (Sweden)

    Gamil A.A. Al-Hazmi

    2017-02-01

    Full Text Available A series of Ni(II–hydrazide complexes were prepared using derivatives of hydrazide ligands. The variation of organic ligand elaborates the mode of coordination of the organic compound referring to the addition of coordinating sites besides the NH–NH–CO group. The octahedral configuration is the major form proposed with most isolated complexes. Mass spectra were used to assure the molecular formula proposed based on the elemental analysis data for most investigated compounds. Thermal analysis as well as kinetic data supports the formula of all investigated complexes especially the presence of coordinating water molecules with most of them. Electrochemical measurements assert the stability of Ni(II oxidation state during the complexation which may be affected during the coordination reaction. pH metric studies as well as the molecular modeling optimization reflect a shadow on the stability of the isolated complexes in solution or in solid state, respectively.

  13. Study on spectral features of terahertz wave propagating in the air

    Science.gov (United States)

    Kang, Shengwu

    2018-03-01

    Now, Terahertz technology has been widely used in many fields, which is mainly related to imaging detection. While the frequency range of the terahertz-wave is located between microwave and visible light, whether the existing visible light principle is applicable to terahertz-wave should be studied again. Through experiment, we measure the terahertz-wave field amplitude distribution on the receiving plane perpendicular to the direction of propagation in the air and picture out the energy distribution curve; derive an energy decay formula of terahertz wave based on the results; design a terahertz wavelength apparatus using the F-P interferometer theory; test the wavelength between 1 and 3 THz from the SIFIR-50THz laser of American Corehent company; finally analyze the related factors affecting the measurement precision including the beam incident angle, mechanical vibration, temperature fluctuation and the refractive index fluctuation.

  14. Fat saturation in dynamic breast MRI at 3 Tesla: is the Dixon technique superior to spectral fat saturation? A visual grading characteristics study

    Energy Technology Data Exchange (ETDEWEB)

    Clauser, P. [University of Udine, Azienda Ospedaliero-Universitaria ' ' S.Maria della Misericordia' ' , Institute of Diagnostic Radiology, Udine (Italy); Medical University of Vienna, Department of Biomedical Imaging and Image-guided interventions, Division of Molecular and Gender Imaging, Vienna (Austria); Pinker, K.; Helbich, T.H.; Kapetas, P.; Bernathova, M.; Baltzer, P.A.T. [Medical University of Vienna, Department of Biomedical Imaging and Image-guided interventions, Division of Molecular and Gender Imaging, Vienna (Austria)

    2014-09-15

    To intra-individually compare the diagnostic image quality of Dixon and spectral fat suppression at 3 T. Fifty consecutive patients (mean age 55.1 years) undergoing 3 T breast MRI were recruited for this prospective study. The image protocol included pre-contrast and delayed post-contrast spectral and Dixon fat-suppressed T1w series. Two independent blinded readers compared spectral and Dixon fat-suppressed series by evaluating six ordinal (1 worst to 5 best) image quality criteria (image quality, delineation of anatomical structures, fat suppression in the breast and axilla, lesion delineation and internal enhancement). Breast density and size were assessed. Data analysis included Spearman's rank correlation coefficient and visual grading characteristics (VGC) analysis. Four examinations were excluded; 48 examinations in 46 patients were evaluated. In VGC analysis, the Dixon technique was superior regarding image quality criteria analysed (P < 0.01). Smaller breast size and lower breast density were significantly (P < 0.01) correlated with impaired spectral fat suppression quality. No such correlation was identified for the Dixon technique, which showed reconstruction-based water-fat mixups leading to insufficient image quality in 20.8 %. The Dixon technique outperformed spectral fat suppression in all evaluated criteria (P < 0.01). Non-diagnostic examinations can be avoided by fat and water image reconstruction. The superior image quality of the Dixon technique can improve breast MRI interpretation. (orig.)

  15. Back to basics: qualitative spectral analysis as an investigatory tool, using calcite as a case study

    International Nuclear Information System (INIS)

    Lyons, R.G.

    1996-01-01

    The Interlab Comparison Project reported at the last meeting of this symposium illustrated a major difficulty in using EPR for dating in archaeology and geology. Different laboratories obtained varying (in some case widely varying) accumulated environmental doses (D e ) for the same material. Given the range of factors which may affect D e , a simple quick means of identifying crucial factors affecting D e is essential in order to target research effectively. Qualitative visual analysis of the ESR spectrum provides such a tool. The complex ESR spectrum is considered in the first instance as the superposition of a number of independent peaks. The changing shape of the spectrum under different conditions can be described in terms of varying contributions of the contributing peaks. This paper outlines the necessary concepts and presents a straightforward procedure by which constituent peaks and their relevant properties may be identified with minimal effort. This enables appropriate methods to be selected which will enhance the dating peak relative to other interfering peaks, reducing systematic bias in the estimate of D e . Speleothem calcite is used as a case study to demonstrate the effectiveness of this pragmatic approach. The concepts and procedures should be equally valuable when examining the ESR dating potential of other materials. (author)

  16. Biogenic silver nanoparticles using Rhinacanthus nasutus leaf extract: synthesis, spectral analysis, and antimicrobial studies.

    Science.gov (United States)

    Pasupuleti, Visweswara Rao; Prasad, T N V; Shiekh, Rayees Ahmad; Balam, Satheesh Krishna; Narasimhulu, Ganapathi; Reddy, Cirandur Suresh; Ab Rahman, Ismail; Gan, Siew Hua

    2013-01-01

    Nanotechnology is gaining momentum due to its ability to transform metals into nanoparticles. The synthesis, characterization, and applications of biologically synthesized nanomaterials have become an important branch of nanotechnology. Plant extracts are a cost-effective, ecologically friendly, and efficient alternative for the large-scale synthesis of nanoparticles. In this study, silver nanoparticles (AgNps) were synthesized using Rhinacanthus nasutus leaf extract. After exposing the silver ions to the leaf extract, the rapid reduction of silver ions led to the formation of AgNps in solution. The synthesis was confirmed by ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy. The in vitro antimicrobial activity of the AgNps synthesized using R. nasutus leaf extract was investigated against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli, Aspergillus niger, and Aspergillus flavus using a disc diffusion method. The AgNps showed potential activity against all of the bacterial strains and fungal colonies, indicating that R. nasutus has the potential to be used in the development of value-added products in the biomedical and nanotechnology-based industries.

  17. Hydrogen bonding interactions between ethylene glycol and water: density, excess molar volume, and spectral study

    Institute of Scientific and Technical Information of China (English)

    ZHANG JianBin; ZHANG PengYan; MA Kai; HAN Fang; CHEN GuoHua; WEI XiongHui

    2008-01-01

    Studies of the density and the excess molar volume of ethylene glycol (EG)-water mixtures were carried out to illustrate the hydrogen bonding interactions of EG with water at different temperatures, The re-sults suggest that a likely complex of 3 ethylene glycol molecules bonding with 4 water molecules in an ethylene glycol-water mixture (EGW) is formed at the maximal excess molar volume, which displays stronger absorption capabilities for SO2 when the concentration of SO2 reaches 400×106 (volume ratio) in the gas phase. Meanwhile, FTIR and UV spectra of EGWs were recorded at various EG concentra-tions to display the hydrogen bonding interactions of EG with water. The FTIR spectra show that the stretching vibrational band of hydroxyl in the EGWs shifts to a lower frequency and the bending vibra-tional band of water shifts to a higher frequency with increasing the EG concentration, respectively. Furthermore, the UV spectra show that the electron transferring band of the hydroxyl oxygen in EG shows red shift with increasing the EG concentration. The frequency shifts in FTIR spectra and the shifts of absorption bands in UV absorption spectra of EGWs are interpreted as the strong hydrogen bonding interactions of the hydrogen atoms in water with the hydroxyl oxygen atoms of EG.

  18. Photometric and spectral studies of the eclipsing polar CRTS CSS081231 J071126+440405

    Science.gov (United States)

    Borisov, N. V.; Gabdeev, M. M.; Shimansky, V. V.; Katysheva, N. A.; Kolbin, A. I.; Shugarov, S. Yu.; Goranskij, V. P.

    2016-01-01

    We present the results of the study of the eclipsing polar CRTS CSS081231 J071126+440405. Photometric observations allowed us to refine the orbital period of the system P_ circ = 0_ \\cdot ^d 0.08137673. Considerable changes in the appearance of the object's spectra have occurred over the period of September 20-21, 2001: the slope of the continuum changed from "red" to "blue", and the variability of the line profiles over the duration of the orbital period has also changed. Doppler maps have shown a shift of the emission line-forming region along the accretion stream closer to the white dwarf. We measured the duration of the eclipse of the system and imposed constraints on the inclination angle 78_ \\cdot ^ circ 7 < i < 79_ \\cdot ^ circ 3. The derived radial velocity amplitude was used to obtain the basic parameters of the system: M 1 = 0.86 ± 0.08 M ⊙, M 2 = 0.18 ± 0.02 M ⊙, q = 0.21 ± 0.01, R L2 = 0.20 ± 0.03 R ⊙, A = 0.80 ± 0.03 R ⊙. The spectra of the object exhibit cyclotron harmonics. Their comparison with model spectra allowed us to determine the parameters of the accretion column: B = 31-34 MG, T e = 10-12 keV, θ = 80-90°, and Λ = 105.

  19. Spectral studies on the interaction of acetylacetone with aluminum-containing MCM-41 mesoporous materials

    International Nuclear Information System (INIS)

    Zanjanchi, M.A.; Vaziri, M.

    2008-01-01

    Diffuse reflectance spectroscopy (DRS) was used to study the interaction of acetylacetone (acac) with the mesoporous aluminum-containing MCM-41 materials. A room temperature synthesis method was used for preparation of purely siliceous MCM-41 and for aluminum-containing MCM-41 materials. Samples with Si/Al ratios of 50, 20, 10 and 5 were synthesized. The synthesized mesoporous materials possess highly ordered structure and high surface area as evidenced from X-ray diffraction and nitrogen physisorption measurements, respectively. The treatment of the as-synthesized aluminum-containing MCM-41 samples with acac shows a distinct band at ∼290 nm. This band is assigned to six coordinated aluminum atoms in the structure which is produced by diffusion of acac molecules through surfactant micelles and their interaction with aluminum atoms. The 290-nm band disappears upon several successive washing of the sample with ethanol. The treatment of the calcined aluminum-containing MCM-41 sample with acac produces the same 290-nm band where its intensity increases with the aluminum content of the sample. The intensity of this band is reduced upon successive ethanol washing, but remains nearly constant after three times washing. This irremovable aluminum species can be assigned to framework aluminum. The measured acidity for our aluminum-containing MCM-41 samples correlates linearly with the intensity of 290-nm band for the ethanol treated samples. This supports the idea that the Bronsted acidity in aluminum-modified MCM-41 samples is a function of the amount of tetrahedral framework aluminum in the structure

  20. Hybrid Spectral Micro-CT: System Design, Implementation, and Preliminary Results

    CERN Document Server

    Bennett, James R; Xu, Qiong; Yu, Hengyong; Walsh, Michael; Butler, Anthony; Butler, Phillip; Cao, Guohua; Mohs, Aaron; Wang, Ge

    2014-01-01

    Spectral CT has proven an important development in biomedical imaging, and there have been several publications in the past years demonstrating its merits in pre-clinical and clinical applications. In 2012, Xu et al. reported that near-term implementation of spectral micro-CT could be enhanced by a hybrid architecture: a narrow-beam spectral "interior" imaging chain integrated with a traditional wide-beam "global" imaging chain. This hybrid integration coupled with compressive sensing (CS)-based interior tomography demonstrated promising results for improved contrast resolution, and decreased system cost and radiation dose. The motivation for the current study is implementation and evaluation of the hybrid architecture with a first-of-its-kind hybrid spectral micro-CT system. Preliminary results confirm improvements in both contrast and spatial resolution. This technology is shown to merit further investigation and potential application in future spectral CT scanner design.

  1. Influence of stereoelectronic effects on the non-opioid analgesics gaboxadol and gaboxadol hydrochloride: Spectral and DFT study

    Science.gov (United States)

    Leenaraj, D. R.; Joe, I. Hubert

    2018-05-01

    The stereoelectronic properties of the molecular structure of most stable conformers of gaboxadol and gaboxadol hydrochloride have been studied using DFT/B3P86-LANL2DZ methodology. The energies of stable conformers of gaboxadol and gaboxadol hydrochloride are -494.2689 and -510.0117 hartrees, respectively. The stability of the molecules arising from stereoelectronic interactions, leading to its bioactivity, has been confirmed using natural bond orbital analysis. The natural bond orbital analysis of donor-acceptor (σ→σ* and n→σ*) interactions showed that the stereoelectronic hyperconjugative and anomeric interactions are exhibited in gaboxadol hydrochloride and gaboxadol, respectively. Lengthening of the axial and equatorial C-H bond lengths and natural population analysis support these results. Spectral features of gaboxadol hydrochloride have been explored by the Fourier transform infrared, Raman and Nuclear magnetic resonance spectroscopic techniques combined with density functional theory computations. NH+ … Cl- hydrogen bonding has been noticeable as a broad and strong absorption in the 2800-2400 cm-1 region. Broad peaks obtained by proton NMR are a result of the quadrupole effect of the N+ atom. Docking studies using representative GABA receptor crystal structures revealed that molecules containing azinane and isoxazole cores fit within the ligand binding domains, and the gaboxadol hydrochloride molecule shows the best binding energy with the 3D32 GABA receptor. Also, gaboxadol hydrochloride has obtained a high value of HOMO energy and a narrow HOMO- LUMO energy gap, which enhances reactivity.

  2. Spectral-fluorescent study of the interaction of the polymethine dye probe Cyan 2 with chondroitin-4-sulfate

    Science.gov (United States)

    Tatikolov, Alexander S.; Akimkin, Timofey M.; Panova, Ina G.; Yarmoluk, Sergiy M.

    2017-04-01

    The noncovalent interaction of the polymethine dye probe 3,3‧,9-trimethylthiacarbocyanine iodide (Cyan 2) with chondroitin-4-sulfate (C4S) in buffer solutions with different pH and in water in the absence of buffers has been studied by spectral-fluorescent methods. It has been shown that in all media studied, at relatively high concentrations, the dye is bound to C4S mainly as a monomer, which is accompanied by a steep rise of fluorescence (the intermediate formation of dye aggregates on the biopolymer is also observed). From the dependence of the fluorescence quantum yield on the concentration of C4S, the parameters of binding of the dye monomer to C4S were obtained: the effective binding constant K, the number of the monomeric C4S units n per one dye monomer bound to C4S, and the fluorescence quantum yield of the bound dye monomer Φfb. The dependence of Φfb (and K) on pH of the medium is not monotonic: it has a minimum in the region of neutral pH and a growth in the regions of acid and basic pH. This can be explained by changing the charge of a C4S macromolecule as a function of pH and related conformational alterations in the biopolymer, which can affect the rigidity of a dye molecule and the energy of its interaction with the biopolymer.

  3. Relationship between macular ganglion cell complex thickness and macular outer retinal thickness: a spectral-domain optical coherence tomography study.

    Science.gov (United States)

    Kita, Yoshiyuki; Kita, Ritsuko; Takeyama, Asuka; Anraku, Ayako; Tomita, Goji; Goldberg, Ivan

    2013-01-01

    To assess the relationship between macular ganglion cell complex and macular outer retinal thicknesses. Case-control study. Forty-two normal eyes and 91 eyes with primary open-angle glaucoma were studied. Spectral-domain optical coherence tomography (RTVue-100) was used to measure the macular ganglion cell complex and macular outer retinal thickness. Ganglion cell complex to outer retinal thickness ratio was also calculated. The relationships between the ganglion cell complex and outer retinal thicknesses and between the ganglion cell complex to outer retinal thickness ratio and outer retinal thickness were evaluated. There was a positive correlation between ganglion cell complex and outer retinal thicknesses in the normal group and the glaucoma group (r = 0.53, P variation in the outer retinal thickness. Therefore, when determining the ganglion cell complex, it seems necessary to consider the outer retinal thickness as well. We propose the ratio as a suitable parameter to account for individual variations in outer retinal thickness. © 2013 The Authors. Clinical and Experimental Ophthalmology © 2013 Royal Australian and New Zealand College of Ophthalmologists.

  4. Synthesis, Characterization and Spectral Studies of Noble Heterobinuclear Complexes of Transition Metal Ions and their Biological Activity

    Directory of Open Access Journals (Sweden)

    Netra Pal Singh

    2011-01-01

    Full Text Available Some noble heterobinuclear complexes of transition metal ions with bis(salicylaldehydemalonyl-dihydrazone in the presence of 5-nitroindazole Cu(II / Ni(II- chloride of the type [ML1M‘L2Cl2] or [ML1FeL2Cl2]Cl, where M = Ni(II, Cu(II and M' = Mn(II, Co(II, have been prepared. All the complexes have been characterized by IR, UV vis and EPR spectroscopy, elemental analysis, magnetic moment and molar conductance measurement. Spectral studies and magnetic moment measurement in DMF suggest the covalent nature of the complexes, except the [ML1FeL2Cl2]Cl complex which is 1:1 electrolyte. An octahedral geometry is proposed for M‘ and square planer for M for the heterobinuclear complexes. The low value of magnetic moment and overlapping EPR signals are due to spin crossover since both of the metals have unpaired electrons with same molecular symmetry. The lowering of the magnetic moment has been discussed. The biological activity (antifungal and antibacterial of the represented compounds has been studied.

  5. Hamiltonian indices and rational spectral densities

    Science.gov (United States)

    Byrnes, C. I.; Duncan, T. E.

    1980-01-01

    Several (global) topological properties of various spaces of linear systems, particularly symmetric, lossless, and Hamiltonian systems, and multivariable spectral densities of fixed McMillan degree are announced. The study is motivated by a result asserting that on a connected but not simply connected manifold, it is not possible to find a vector field having a sink as its only critical point. In the scalar case, this is illustrated by showing that only on the space of McMillan degree = /Cauchy index/ = n, scalar transfer functions can one define a globally convergent vector field. This result holds both in discrete-time and for the nonautonomous case. With these motivations in mind, theorems of Bochner and Fogarty are used in showing that spaces of transfer functions defined by symmetry conditions are, in fact, smooth algebraic manifolds.

  6. Global and Arctic climate engineering: numerical model studies.

    Science.gov (United States)

    Caldeira, Ken; Wood, Lowell

    2008-11-13

    We perform numerical simulations of the atmosphere, sea ice and upper ocean to examine possible effects of diminishing incoming solar radiation, insolation, on the climate system. We simulate both global and Arctic climate engineering in idealized scenarios in which insolation is diminished above the top of the atmosphere. We consider the Arctic scenarios because climate change is manifesting most strongly there. Our results indicate that, while such simple insolation modulation is unlikely to perfectly reverse the effects of greenhouse gas warming, over a broad range of measures considering both temperature and water, an engineered high CO2 climate can be made much more similar to the low CO2 climate than would be a high CO2 climate in the absence of such engineering. At high latitudes, there is less sunlight deflected per unit albedo change but climate system feedbacks operate more powerfully there. These two effects largely cancel each other, making the global mean temperature response per unit top-of-atmosphere albedo change relatively insensitive to latitude. Implementing insolation modulation appears to be feasible.

  7. Born Global from the Resource-Based Theory: A Case Study in Colombia

    Directory of Open Access Journals (Sweden)

    Alexander Tabares

    2015-07-01

    Full Text Available This paper describes how a born global firm goes into international market from inception at its early years. The objective of this paper is to analyze from the resource-based theory how a born global firm engages in international market. This empirical investigation has been carried out as an explorative single-case study, a high-tech firm, Digital Partner, based in Medellin, Antioquia. The main findings of the research show that organizational capabilities based on intellectual capital are crucial for the development of a born global. Thus, capabilities such as entrepreneurship, global vision, internationally market knowledge, learning management, IT capabilities, technological innovation, collaborative work, networks and customer orientation are recurrent and they correspond to other similar research results. Contributions of the study are both academic (for the advance of the research in born global field and practical (for the design of governmental policies to foster born global firms.

  8. Global-Mindedness and Intercultural Competence: A Quantitative Study of Pre-Service Teachers

    Science.gov (United States)

    Cui, Qi

    2013-01-01

    This study assessed pre-service teachers' levels of global-mindedness and intercultural competence using the Global-Mindedness Scale (GMS) and the Cultural Intelligence Scale (CQS) and investigated the correlation between the two. The study examined whether the individual scale factors such as gender, perceived competence in non-native language or…

  9. Born global companies: A case study about the internationalization behaviours of Portuguese companies

    OpenAIRE

    Carlos, Diogo Miguel Pais Grou Simões

    2015-01-01

    Portuguese Born Global Companies have been performing an important role in the Portuguese market, mainly due to their innovative ideas and the positive contribution to exportations. This study focuses on the international strategies of four of these companies, comparing them with four international Non-Born Global Companies, in qualitative analysis. It will be possible to see a preference by the Non-Born Global Companies over proximate cultural countries. By following opportunities instead...

  10. Syntheses, Magnetic and Spectral Studies on the Coordination Compounds of the Polystyrene-anchored Thiazolidin-4-one

    Directory of Open Access Journals (Sweden)

    Dinesh Kumar

    2012-01-01

    Full Text Available The reaction between polystyrene 3-formylsalicylate and thiophene-2-carboxylic acid hydrazide in DMF in the presence of ethyl acetate results in the formation of polystyrene N-(2-carbamoylthienyl-3'-carboxy-2'-hydroxybenzylideneimine (I. A benzene suspension of I reacts with mercaptoacetic acid and forms the polystyrene N-(2-carbamoylthienyl-C-(3'-carboxy-2'-hydroxyphenyl thiazolidin-4-one, PSCH2–LH2 (II. A DMF suspension of II reacts with Zn(II, Co(II, Cu(II, Zr(OH2(IV and MoO2(VI ions and forms the corresponding polystyrene-anchored coordination compounds, [PSCH2–LZn(DMF] (III, [PSCH2–LCo(DMF3] (IV, [PSCH2–LHCu(OAc] (V, [PSCH2–LH2Zr(OH2(OAc2] (VI and [PSCH2–LHMoO2(acac] (VII respectively. The polystyrene-anchored coordination compounds have been characterized on the basis of elemental analyses, spectral (IR, reflectance, ESR studies and magnetic susceptibility measurements. II acts as a neutral tridentate ONS donor ligand in VI, a monobasic bidentate OS donor ligand in VII, a monobasic tridentate ONS donor ligand in V and a dibasic tridentate ONO donor ligand in III and IV. The acetato groups behave as monodentate ligands in V and VI. A square-planar structure for V, a tetrahedral structure for III, an octahedral structure for IV and VII and a pentagonal-bipyramidal structure for VI are suggested.

  11. Spectral Study of A 1Π–X 1Σ+ Transitions of CO Relevant to Interstellar Clouds

    Science.gov (United States)

    Cheng, Junxia; Zhang, Hong; Cheng, Xinlu

    2018-05-01

    Highly correlated ab initio calculations were performed for an accurate determination of the A 1Π–X 1Σ+ system of the CO molecule. A highly accurate multi-reference configuration interaction approach was used to investigate the potential energy curves (PECs) and the transition dipole moment curve (TDMC). The resultant PECs and TDMC found by using the aug-cc-pV5Z (aV5Z) basis set and 5330 active spaces are in good agreement with the experimental data. Moreover, the Einstein A coefficients, lifetimes, ro-vibrational intensities, absorption oscillator strengths, and integrated cross sections are calculated so that the vibrational bands include v″ = 0–39 \\to v‧ = 0–23. For applications in the atmosphere and interstellar clouds, we studied the transition lineshapes to Gaussian and Lorentzian profiles at different temperatures and pressures. The intensities were calculated at high temperature that was used to satisfy some astrophysical applications, such as in planetary atmospheres. The results are potentially useful for important SAO/NASA Astrophysics Data System and databases such as HITRAN, HITEMP, and the National Institute of Standards and Technology. Because the results from many laboratory techniques and our calculations now agree, analyses of interstellar CO based on absorption from A 1Π–X 1Σ+ are no longer hindered by present spectral parameters.

  12. Synthesis, spectral characterisation, morphology, biological activity and DNA cleavage studies of metal complexes with chromone Schiff base

    Directory of Open Access Journals (Sweden)

    P. Kavitha

    2016-07-01

    Full Text Available Cu(II, Co(II, Ni(II and Zn(II complexes have been synthesized using 3-((pyridine-2-yliminomethyl-4H-chromen-4-one as a ligand derived from 3-formyl chromone and 2-amino pyridine. All the complexes were characterised by analytical, conductivity, IR, electronic, magnetic, ESR, thermal, powder XRD and SEM studies. The analytical data revealed that the metal to ligand molar ratio is 1:2 in all the complexes. Molar conductivity data indicates that all the complexes are neutral in nature. On the basis of magnetic and electronic spectral data, octahedral geometry is proposed for all the complexes. Thermal behaviour of the synthesized complexes indicates the coordinated and lattice water molecules are present in the complexes. The X-ray diffraction data suggest a triclinic system for all compounds. Different surface morphologies were identified from SEM micrographs. All metal complexes exhibit fluorescence. The antimicrobial and nematicidal activity data show that metal complexes are more potent than the parent ligand. The DNA cleavage activity of the ligand and its metal complexes were observed in the presence of H2O2.

  13. A comparative study of the spectral, fluorometric properties and photostability of natural curcumin, iron- and boron- complexed curcumin

    Science.gov (United States)

    Mohammed, Fatima; Rashid-Doubell, Fiza; Cassidy, Seamas; Henari, Fryad

    2017-08-01

    Curcumin is a yellow phenolic compound with a wide range of reported biological effects. However, two main obstacles hinder the use of curcumin therapeutically, namely its poor bioavailability and photostability. We have synthesized two curcumin complexes, the first a boron curcumin complex (B-Cur2) and the second an iron (Fe-Cur3) complex of curcumin. Both derivatives showed high fluorescence efficiency (quantum yield) and greater photostability in solution. The improved photostability could be attributed to the coordination structures and the removal of β-diketone group from curcumin. The fluorescence and ultra violet/visible absorption spectra of curcumin, B-Cur2 and Fe-Cur3 all have a similar spectral pattern when dissolved in the same organic solvent. However, a shift towards a lower wavelength was observed when moving from polar to non-polar solvents, possibly due to differences in solvent polarity. A plot of Stokes' shift vs the orientation polarity parameter (Δf) or vs the solvent polarity parameter (ET 30) showed an improved correlation between the solvent polarity parameter than with the orientation polarity parameter and indicating that the red shift observed could be due to hydrogen-bonding between the solvent molecules. A similar association was obtained when Stokes' shift was replaced by maximum synchronous fluorescence. Both B-Cur2 and Fe-Cur3 had larger quantum yields than curcumin, suggesting they may be good candidates for medical imaging and in vitro studies.

  14. Computational and spectral studies of 6-phenylazo-3-(p-tolyl)-2H-chromen-2-one

    Science.gov (United States)

    Manimekalai, A.; Vijayalakshmi, N.

    2015-02-01

    6-Phenylazo-3-(p-tolyl)-2H-chromen-2-one 4 was prepared and characterized by IR, 1H, and 13C NMR spectral studies. The optimized structure of the chromen-2-one 4 was investigated by the Gaussian 03 B3LYP density functional method calculations at 6-31G(d,p) basis set. The gauge-independent atomic orbital (GIAO) 13C and 1H chemical shift calculations for the synthesized chromen-2-one in CDCl3 were also made by the same method. The computed IR frequencies of the chromen-2-one and the corresponding vibrational assignments were analyzed by means of potential energy distribution (PED%) calculation using vibrational energy distribution analysis (VEDA) program. The first order hyperpolarizability (βtot), polarizability (α) and dipole moment (μ) were calculated using 6-311G(d,p) basis set and the nonlinear optical (NLO) properties are also addressed theoretically. Stability of the chromen-2-one 4 molecule has been analyzed by calculating the intramolecular charge transfer using natural bond order (NBO) analysis. The molecular electrostatic potentials, HOMO-LUMO energy gap and geometrical parameters were also computed. Topological properties of the electronic charge density in chromen-2-one 4 were analyzed employing the Bader's Atoms in Molecule (AIM) theory which indicated the presence of intramolecular hydrogen bond in the molecule.

  15. Structural, electronic and spectral properties of carborane-containing boron dipyrromethenes (BODIPYs): A first-principles study

    Science.gov (United States)

    Li, Xiaojun

    2017-10-01

    In this work, we reported the geometrical structures, electronic and spectral properties of the carborane-containing BODIPYs complexes using the density functional theory calculations. In two structures, the calculated main bond lengths and bond angels of structural framework are consistent with X-ray experiment, and the two BODIPYs complexes are thermodynamically and kinetically stable. The strongest DOS band is mainly dominated by the Bsbnd B and Bsbnd H σ-bonds of carborane fragment, whereas the π-type MOs on the pyrromethene fragment contribute to the high-energy DOS bands. Analysis of the AdNDP chemical bonding indicates that the carborane cage can be stabilized by eleven delocalized 3csbnd 2e and two delocalized 4csbnd 2e σ-bonds, while the pyrromethene fragment corresponds to five delocalized 3csbnd 2e π-bonds. In addition, the main characteristic peaks of the two simulated IR spectra for the BODIPYs complexes are properly assigned. Hopefully, all these results will be helpful for understanding the electronic structures, and further stimulate the study on the biological and medical applications.

  16. Pd (II) complexes of bidentate chalcone ligands: Synthesis, spectral, thermal, antitumor, antioxidant, antimicrobial, DFT and SAR studies

    Science.gov (United States)

    Gaber, Mohamed; Awad, Mohamed K.; Atlam, Faten M.

    2018-05-01

    The ligation behavior of two chalcone ligands namely, (E)-3-(4-chlorophenyl)-1-(pyridin-2-yl)prop-2-en-1-one (L1) and (E)-3-(4-methoxyphenyl)-1-(pyridin-2-yl)prop-2-en-1-one (L2), towards the Pd(II) ion is determined. The structures of the complexes are elucidated by elemental analysis, spectral methods (IR, electronic and NMR spectra) as well as the conductance measurements and thermal analysis. The metal complexes exhibit a square planar geometrical arrangement. The kinetic and thermodynamic parameters for some selected decomposition steps have been calculated. The antimicrobial, antioxidant and anticancer activities of the chalcones and their Pd(II) complexes have been evaluated. Molecular orbital computations are performed using DFT at B3LYP level with 6-31 + G(d) and LANL2DZ basis sets to access reliable results to the experimental values. The calculations are performed to obtain the optimized molecular geometry, charge density distribution, extent of distortion from regular geometry. Thermodynamic parameters for the investigated compounds are also studied. The calculations confirm that the investigated complexes have square planner geometry, which is in a good agreement with the experimental observation.

  17. Abnormal resting state effective connectivity within the default mode network in major depressive disorder: A spectral dynamic causal modeling study.

    Science.gov (United States)

    Li, Liang; Li, Baojuan; Bai, Yuanhan; Liu, Wenlei; Wang, Huaning; Leung, Hoi-Chung; Tian, Ping; Zhang, Linchuan; Guo, Fan; Cui, Long-Biao; Yin, Hong; Lu, Hongbing; Tan, Qingrong

    2017-07-01

    Understanding the neural basis underlying major depressive disorder (MDD) is essential for the diagnosis and treatment of this mental disorder. Aberrant activation and functional connectivity of the default mode network (DMN) have been consistently found in patients with MDD. It is not known whether effective connectivity within the DMN is altered in MDD. The primary object of this study is to investigate the effective connectivity within the DMN during resting state in MDD patients before and after eight weeks of antidepressant treatment. We defined four regions of the DMN (medial frontal cortex, posterior cingulate cortex, left parietal cortex, and right parietal cortex) for each participant using a group independent component analysis. The coupling parameters reflecting the causal interactions among the DMN regions were estimated using spectral dynamic causal modeling (DCM). Twenty-seven MDD patients and 27 healthy controls were included in the statistical analysis. Our results showed declined influences from the left parietal cortex to other DMN regions in the pre-treatment patients as compared with healthy controls. After eight weeks of treatment, the influence from the right parietal cortex to the posterior cingulate cortex significantly decreased. These findings suggest that the reduced excitatory causal influence of the left parietal cortex is the key alteration of the DMN in patients with MDD, and the disrupted causal influences that parietal cortex exerts on the posterior cingulate cortex is responsive to antidepressant treatment.

  18. The Global Burden of Mental, Neurological and Substance Use Disorders: An Analysis from the Global Burden of Disease Study 2010

    Science.gov (United States)

    Whiteford, Harvey A.; Ferrari, Alize J.; Degenhardt, Louisa; Feigin, Valery; Vos, Theo

    2015-01-01

    Background The Global Burden of Disease Study 2010 (GBD 2010), estimated that a substantial proportion of the world’s disease burden came from mental, neurological and substance use disorders. In this paper, we used GBD 2010 data to investigate time, year, region and age specific trends in burden due to mental, neurological and substance use disorders. Method For each disorder, prevalence data were assembled from systematic literature reviews. DisMod-MR, a Bayesian meta-regression tool, was used to model prevalence by country, region, age, sex and year. Prevalence data were combined with disability weights derived from survey data to estimate years lived with disability (YLDs). Years lost to premature mortality (YLLs) were estimated by multiplying deaths occurring as a result of a given disorder by the reference standard life expectancy at the age death occurred. Disability-adjusted life years (DALYs) were computed as the sum of YLDs and YLLs. Results In 2010, mental, neurological and substance use disorders accounted for 10.4% of global DALYs, 2.3% of global YLLs and, 28.5% of global YLDs, making them the leading cause of YLDs. Mental disorders accounted for the largest proportion of DALYs (56.7%), followed by neurological disorders (28.6%) and substance use disorders (14.7%). DALYs peaked in early adulthood for mental and substance use disorders but were more consistent across age for neurological disorders. Females accounted for more DALYs in all mental and neurological disorders, except for mental disorders occurring in childhood, schizophrenia, substance use disorders, Parkinson’s disease and epilepsy where males accounted for more DALYs. Overall DALYs were highest in Eastern Europe/Central Asia and lowest in East Asia/the Pacific. Conclusion Mental, neurological and substance use disorders contribute to a significant proportion of disease burden. Health systems can respond by implementing established, cost effective interventions, or by supporting the

  19. The global burden of mental, neurological and substance use disorders: an analysis from the Global Burden of Disease Study 2010.

    Science.gov (United States)

    Whiteford, Harvey A; Ferrari, Alize J; Degenhardt, Louisa; Feigin, Valery; Vos, Theo

    2015-01-01

    The Global Burden of Disease Study 2010 (GBD 2010), estimated that a substantial proportion of the world's disease burden came from mental, neurological and substance use disorders. In this paper, we used GBD 2010 data to investigate time, year, region and age specific trends in burden due to mental, neurological and substance use disorders. For each disorder, prevalence data were assembled from systematic literature reviews. DisMod-MR, a Bayesian meta-regression tool, was used to model prevalence by country, region, age, sex and year. Prevalence data were combined with disability weights derived from survey data to estimate years lived with disability (YLDs). Years lost to premature mortality (YLLs) were estimated by multiplying deaths occurring as a result of a given disorder by the reference standard life expectancy at the age death occurred. Disability-adjusted life years (DALYs) were computed as the sum of YLDs and YLLs. In 2010, mental, neurological and substance use disorders accounted for 10.4% of global DALYs, 2.3% of global YLLs and, 28.5% of global YLDs, making them the leading cause of YLDs. Mental disorders accounted for the largest proportion of DALYs (56.7%), followed by neurological disorders (28.6%) and substance use disorders (14.7%). DALYs peaked in early adulthood for mental and substance use disorders but were more consistent across age for neurological disorders. Females accounted for more DALYs in all mental and neurological disorders, except for mental disorders occurring in childhood, schizophrenia, substance use disorders, Parkinson's disease and epilepsy where males accounted for more DALYs. Overall DALYs were highest in Eastern Europe/Central Asia and lowest in East Asia/the Pacific. Mental, neurological and substance use disorders contribute to a significant proportion of disease burden. Health systems can respond by implementing established, cost effective interventions, or by supporting the research necessary to develop better

  20. Contrast-enhanced spectral mammography in recalls from the Dutch breast cancer screening program : validation of results in a large multireader, multicase study

    NARCIS (Netherlands)

    Lalji, U C; Houben, I P L; Prevos, R; Gommers, S; van Goethem, M; Vanwetswinkel, S; Pijnappel, R; Steeman, R; Frotscher, C; Mok, W; Nelemans, P; Smidt, M L; Beets-Tan, R G; Wildberger, J E; Lobbes, M B I

    2016-01-01

    OBJECTIVES: Contrast-enhanced spectral mammography (CESM) is a promising problem-solving tool in women referred from a breast cancer screening program. We aimed to study the validity of preliminary results of CESM using a larger panel of radiologists with different levels of CESM experience.

  1. Studying the effect of spectral variations intensity of the incident solar radiation on the Si solar cells performance

    Directory of Open Access Journals (Sweden)

    Ahmed Elsayed Ghitas

    2012-12-01

    Full Text Available Solar spectral variation is important in characterization of photovoltaic devices. We present results of an experimental investigation of the effects of the daily spectral variation on the device performance of multicrystalline silicon photovoltaic module. The investigation concentrate on the analysis of outdoor solar spectral measurements carried out at 1 min intervals on clear sky days. Short circuit current and open circuit voltage have been measured to describe the module electrical performance. We have shown that the shift in the solar spectrum towards infrared has a negative impact on the device performance of the module. The spectral bands in the visible region contribute more to the short circuit current than the bands in the infrared region while the ultraviolet region contributes least. The quantitative effect of the spectral variation on the performance of the photovoltaic module is reflected on their respective device performance parameters. The decrease in the visible and the increase in infrared of the radiation spectra account for the decreased current collection and hence power of the module.

  2. Spatiotemporal Built-up Land Density Mapping Using Various Spectral Indices in Landsat-7 ETM+ and Landsat-8 OLI/TIRS (Case Study: Surakarta City)

    Science.gov (United States)

    Risky, Yanuar S.; Aulia, Yogi H.; Widayani, Prima

    2017-12-01

    Spectral indices variations support for rapid and accurate extracting information such as built-up density. However, the exact determination of spectral waves for built-up density extraction is lacking. This study explains and compares the capabilities of 5 variations of spectral indices in spatiotemporal built-up density mapping using Landsat-7 ETM+ and Landsat-8 OLI/TIRS in Surakarta City on 2002 and 2015. The spectral indices variations used are 3 mid-infrared (MIR) based indices such as the Normalized Difference Built-up Index (NDBI), Urban Index (UI) and Built-up and 2 visible based indices such as VrNIR-BI (visible red) and VgNIR-BI (visible green). Linear regression statistics between ground value samples from Google Earth image in 2002 and 2015 and spectral indices for determining built-up land density. Ground value used amounted to 27 samples for model and 7 samples for accuracy test. The classification of built-up density mapping is divided into 9 classes: unclassified, 0-12.5%, 12.5-25%, 25-37.5%, 37.5-50%, 50-62.5%, 62.5-75%, 75-87.5% and 87.5-100 %. Accuracy of built-up land density mapping in 2002 and 2015 using VrNIR-BI (81,823% and 73.235%), VgNIR-BI (78.934% and 69.028%), NDBI (34.870% and 74.365%), UI (43.273% and 64.398%) and Built-up (59.755% and 72.664%). Based all spectral indices, Surakarta City on 2000-2015 has increased of built-up land density. VgNIR-BI has better capabilities for built-up land density mapping on Landsat-7 ETM + and Landsat-8 OLI/TIRS.

  3. Disability, economic globalization and privatization: A case study of India

    DEFF Research Database (Denmark)

    Hiranandani, Vanmala Sunder

    2012-01-01

    have benefitted middle-class and highly-skilled disabled persons, the majority of people with disabilities have been left out of India's economic affluence. We contend that India's globalized economy and reduced state role necessitate renewed understanding of human rights, including disability rights.......People with disabilities are one of the most disenfranchised groups in India. Standardized measurements of disability in India and internationally have overlooked the linkages between the economy and disability. In recent decades, neo-liberal economic reforms imposed in developing countries, under...... investigates the implications of economic restructuring in the arenas of social programs, education, employment, accessibility, health, agriculture and food security, and water and land acquisition from a disability perspective. Our analysis shows that while increased employment opportunities and accessibility...

  4. Global case studies/reports are really useful for learning Global Health?

    Directory of Open Access Journals (Sweden)

    Sudip Bhattacharya

    2017-12-01

    Full Text Available In medical sciences ,a case report means a comprehensive description of the symptoms ,signs, diagnosis , treatment, and follow-up of an individual patient. It may or may not contain a demographic profile of the patient, but generally depicts an unusual or novel manifestation. Case reports are basically professional chronicles that offer an important feedback on clinical practice guiding principle and offer an outline for early indicators of effectiveness, adverse events, and cost. They can be shared for scientific or educational purposes. A case report is usually considered as a type of an anecdotal evidence. Due to their inherentmethodological  limitations, i.e.  lack of statistical sampling, case reports are placed at the foot of the grading of clinical evidence. Yet, case reports do have genuinely valuable roles in clinical research and evidence based medicine. In precise, they have facilitated to recognize of new diseases i.e. Ebola, Zika etc.  Clinical trial is much lengthier and resource consuming that a case report, so it is now gaining popularity among clinical researchers. In fact, there is a definite need to further popularize the concept of case reports.With the consonance of case reports, in clinical trials the concept of sample size calculation is rapidly changing.  Such trials are labeled as “n-of-1 or single subject clinical trials.” It this  trials, the researcher consider an individual patient as the sole unit of observation in a study. The final goal of this trial is to determine the optimal intervention for an individual patient by using objective driven criteria.Despite their clear appeal and extensive use in educational settings, n-of-1 trials have been used sparingly in medical settings. This is because that n-of-1 trials demand serious attention among the health research and clinical care communities and it is focused on individualized medicine. Across the globe people live in diverse circumstances

  5. Global case studies/reports are really useful for learning Global Health?

    Directory of Open Access Journals (Sweden)

    Sudip Bhattacharya

    2017-12-01

    Full Text Available In medical sciences ,a case report means a comprehensive description of the symptoms ,signs, diagnosis , treatment, and follow-up of an individual patient. It may or may not contain a demographic profile of the patient, but generally depicts an unusual or novel manifestation. Case reports are basically professional chronicles that offer an important feedback on clinical practice guiding principle and offer an outline for early indicators of effectiveness, adverse events, and cost. They can be shared for scientific or educational purposes. A case report is usually considered as a type of an anecdotal evidence. Due to their inherentmethodological  limitations, i.e.  lack of statistical sampling, case reports are placed at the foot of the grading of clinical evidence. Yet, case reports do have genuinely valuable roles in clinical research and evidence based medicine. In precise, they have facilitated to recognize of new diseases i.e. Ebola, Zika etc.  Clinical trial is much lengthier and resource consuming that a case report, so it is now gaining popularity among clinical researchers. In fact, there is a definite need to further popularize the concept of case reports.With the consonance of case reports, in clinical trials the concept of sample size calculation is rapidly changing.  Such trials are labeled as “n-of-1 or single subject clinical trials.” It this  trials, the researcher consider an individual patient as the sole unit of observation in a study. The final goal of this trial is to determine the optimal intervention for an individual patient by using objective driven criteria.Despite their clear appeal and extensive use in educational settings, n-of-1 trials have been used sparingly in medical settings. This is because that n-of-1 trials demand serious attention among the health research and clinical care communities and it is focused on individualized medicine. Across the globe people live in diverse circumstances

  6. On the social nature of global self-esteem: a replication study.

    Science.gov (United States)

    Stephan, Yannick; Maiano, Christophe

    2007-10-01

    Few researchers have considered the relationship between global self-esteem and the reflected appraisal of others in one's life, or how reflected appraisals and global self-esteem may change as a result of interpersonal feedback. In this study, the authors collected data from 110 undergraduate students on (a) their global self-esteem and the reflected appraisals of multiple others in their lives and (b) how these dimensions changed in hypothetical interpersonal-feedback situations. Results showed that participants' global self-esteem was related to the reflected appraisals of their fathers, teachers, and friends. The results also indicated that others' reflected appraisals and the individual's global self-esteem fluctuated according to the nature (i.e., positive vs. negative) of the hypothetical interpersonal feedback. Overall, the findings emphasize the social nature and regulation of global self-esteem.

  7. Thermodynamic Study of the Ion-Pair Complexation Equilibria of Dye and Surfactant by Spectral Titration and Chemometric Analysis

    Directory of Open Access Journals (Sweden)

    Hakimeh Abbasi Awal

    2017-12-01

    Full Text Available Surfactant-dye interactions are very important in chemical and dyeing processes. The dyes interact strongly with surfactant and show new spectrophotometric properties, so the UV-vis absorption spectrophotometric method has been used to study this process and extract some thermodynamic parameters. In this work, the association equilibrium between ionic dyes and ionic surfactant were studied by analyzing spectrophotometric data using chemometric methods. Methyl orange and crystal violet were selected as a model of cationic and anionic dyes respectively. Also sodium dodecyl sulphate and cetyltrimethylammonium bromide were selected as anionic and cationic surfactant, respectively. Hard model methods such as target transform fitting (TTF classical multi-wavelength fitting and soft model method such as multivariate curve resolution (MCR were used to analyze data that were recorded as a function of surfactant concentration in premicellar and postmicellar regions. Hard model methods were used to resolve data using ion-pair model in premicellar region in order to extract the concentration and spectral profiles of individual components and also related thermodynamic parameters. The equilibrium constants and other thermodynamic parameters of interaction of dyes with surfactants were determined by studying the dependence of their absorption spectra on the temperature in the range 293–308 K at concentrations of 5 × 10−6 M and 8 × 10−6 M for dye crystal violet and methyl orange, respectively. In postmicellar region, the MCR-ALS method was applied for resolving data and getting the spectra and concentration profiles in complex mixtures of dyes and surfactants.

  8. Bombay in Salman Rushdie’s novels: a study from global perspective.

    Directory of Open Access Journals (Sweden)

    Madhumita Roy

    2014-12-01

    Full Text Available Bombay, the city where Salman Rushdie spent his childhood, features prominently in four of his novels, namely Midnight’s Children (1981, The Satanic Verses (1988, The Moor’s Last Sigh (1995 and The Ground Beneath Her Feet (1999. However, in traditional literary approaches, the built environment and the materiality of Bombay evident in Rushdie’s fiction are largely lost disallowing Rushdie’s portrayal of the city to be explained as the real-imaged lived space, which Henri Lefebvre (1991 defines as “representational space” and Edward Soja (1996 as “third space”. In the globalized world of ubiquitous placelessness, the strategies and the tactics of recovering the lived space, sometimes involving the micro level of the body and sometimes larger scales such as the communities, are matters of great significance for the prominent spatial thinkers of our times. Therefore, by considering that Rushdie’s depiction of Bombay provides an access to its lived space, and particularly concentrating on the issues related to the land-reclamation in Bombay, this paper finally aims to explore how Rushdie’s sense of place is a progressive, global sense of place, which neither collapses in to a reactionary nostalgia; nativist bigotry, nor does it surrender to a spectral, deterritorialized globality.

  9. New indicators for global crop monitoring in CropWatch -case study in North China Plain

    International Nuclear Information System (INIS)

    Bingfang, Wu; Miao, Zhang; Hongwei, Zeng; Guoshui, Liu; Sheng, Chang; Gommes, René

    2014-01-01

    CropWatch is a monitoring system developed and operated by the Institute of Remote Sensing and Digital Earth (Chinese Academy of Sciences) to provide global-scale crop information. Now in its 15th year of operation, CropWatch was modified several times to be a timely, comprehensive and independent global agricultural monitoring system using advanced remote sensing technology. Currently CropWatch is being upgraded with new indicators based on new sensors, especially those on board of China Environmental Satellite (HJ-1 CCD), the Medium Resolution Spectral Imager (MERSI) on Chinese meteorological satellite (FY-3A) and cloud classification products of FY-2. With new satellite data, CropWatch will generate new indicators such as fallow land ratio (FLR), crop condition for irrigated (CCI) and non-irrigated (CCNI) areas separately, photosynthetically active radiation (PAR), radiation use efficiency for the photosynthetically active radiation (RUE PAR ) and cropping index (CI) with crop rotation information (CRI). In this paper, the methods for monitoring the new indicators are applied to the North China Plain which is one of the major grain producing areas in China. This paper shows the preliminary results of the new indicators and methods; they still need to be thoroughly validated before being incorporated into the operational CropWatch system. In the future, the new and improved indicators will help us to better understand the global situation of food security

  10. Becoming Global Elites through Transnational Language Learning?: The Case of Korean Early Study Abroad in Singapore

    Science.gov (United States)

    Bae, Sohee; Park, Joseph Sung-Yul

    2016-01-01

    Since the late 1990s, early study abroad (ESA) in English-speaking countries has been a popular educational strategy for pre-university Korean students to acquire important language skills such as global English, which is imagined to help them prepare for the competition in global educational and occupational market. However, as ESA, commonly…

  11. Rationale and design of INTERSTROKE: a global case-control study of risk factors for stroke

    DEFF Research Database (Denmark)

    O'Donnell, M; Serpault, Damien Xavier; Diener, C

    2010-01-01

    Stroke is a major global health problem. It is the third leading cause of death and the leading cause of adult disability. INTERHEART, a global case-control study of acute myocardial infarction in 52 countries (29,972 participants), identified nine modifiable risk factors that accounted for >90% ...

  12. The Study Abroad Experience: A Crucial Element in Globalizing Business School Programs

    Science.gov (United States)

    Mangiero, George A.; Kraten, Michael

    2011-01-01

    Globalization is a fundamental reality of modern business practice. Participation in a study abroad program is a crucial element in helping students become well rounded global business leaders; it is an increasingly important element of a well rounded business curriculum. A semester or summer abroad, properly conceived and designed, can provide…

  13. A Quantitative Study of Global Software Development Teams, Requirements, and Software Projects

    Science.gov (United States)

    Parker, Linda L.

    2016-01-01

    The study explored the relationship between global software development teams, effective software requirements, and stakeholders' perception of successful software development projects within the field of information technology management. It examined the critical relationship between Global Software Development (GSD) teams creating effective…

  14. Epidemiological and virological characteristics of influenza B: results of the global influenza B study.

    NARCIS (Netherlands)

    Caini, S.; Sue Huang, Q.; Ciblak, M.A.; Kusznierz, G.; Owen, R.; Wangchuk, S.; Henriques, C.M.P.; Njouom, R.; Fasce, R.A.; Yu, H.; Feng, L.; Zambon, M.; Clara, A.W.; Kosasih, H.; Puzelli, S.; Kasjo, H.A.; Emukule, G.; Hereaud, J.M.; Ang, L.W.; Venter, M.; Mironenko, A.; Brammer, L.; Mai, L.T.Q.; Schellevis, F.; Plotkin, S.; Paget, J.

    2015-01-01

    Introduction: Literature on influenza focuses on influenza A, despite influenza B having a large public health impact. The Global Influenza B Study aims to collect information on global epidemiology and burden of disease of influenza B since 2000. Methods Twenty-six countries in the Southern (n = 5)

  15. Studying the government of global climate change at the intersection of governmentality and proto-governmentality

    DEFF Research Database (Denmark)

    Lindegaard, Laura Bang

    nor global and, moreover, views those sites as negotiated in various, contingent and continuously accomplished longer and shorter connections (cf. e.g. Kendall, 2004). Considering this, the paper suggests an approach for studying the accomplishment of governmental rationalities of global citizenship...

  16. Assessing Global Learning in Short-Term Study Abroad: Population, Environment, and Society in Shanghai

    Science.gov (United States)

    Core, Rachel S.

    2017-01-01

    This teaching note suggests that a short-term study abroad program embedded within a longer course can be a tool for enhancing global learning. The work uses the Association of American Colleges and Universities (AAC&U) Global Learning VALUE rubric to evaluate student work from a spring break seminar to Shanghai, China. The seminar was…

  17. Epidemiological and virological characteristics of influenza B: results of the Global Influenza B Study

    NARCIS (Netherlands)

    Caini, S.; Huang, Q.S.; Ciblak, M.A.; Kusznierz, G.; Owen, R.; Wangchuk, S.; Henriques, C.M.P.; Njouom, R.; Fasce, R.A.; Yu, H.J.; Feng, L.Z.; Zambon, M.; Clara, A.W.; Kosasih, H.; Puzelli, S.; Kadjo, H.A.; Emukule, G.; Heraud, J.M.; Ang, L.W.; Venter, M.; Mironenko, A.; Brammer, L.; Mai, L.T.Q.; Schellevis, F.G.; Plotkin, S.; Paget, J.

    2015-01-01

    Introduction: Literature on influenza focuses on influenza A, despite influenza B having a large public health impact. The Global Influenza B Study aims to collect information on global epidemiology and burden of disease of influenza B since 2000. Methods: Twenty-six countries in the Southern (n=5)

  18. Epidemiological and virological characteristics of influenza B: results of the Global Influenza B Study

    NARCIS (Netherlands)

    Caini, S.; Huang, Q.S.; Ciblak, M.A.; Kusznierz, G.; Owen, R.; Wangchuk, S.; Henriques, C.M.; Njouom, R.; Fasce, R.A.; Yu, H.; Feng, L.; Zambon, M.; Clara, A.W.; Kosasih, H.; Puzelli, S.; Kadjo, H.A.; Emukule, G.; Heraud, J.M.; Ang, L.W.; Venter, M.; Mironenko, A.; Brammer, L.; Mai, T.Q. le; Schellevis, F.; Plotkin, S.; Paget, J.

    2015-01-01

    INTRODUCTION: Literature on influenza focuses on influenza A, despite influenza B having a large public health impact. The Global Influenza B Study aims to collect information on global epidemiology and burden of disease of influenza B since 2000. METHODS: Twenty-six countries in the Southern (n =

  19. Cross-Cultural Management Learning through Innovative Pedagogy: An Exploratory Study of Globally Distributed Student Teams

    Science.gov (United States)

    Bartel-Radic, Anne; Moos, J. Chris; Long, Suzanna K.

    2015-01-01

    This article presents an innovative pedagogy based on student participation in globally distributed project teams. The study questions the link between student learning of intercultural competence and the global teaming experience. Data was collected from 115 students participating in 22 virtual intercultural teams. Results revealed that students…

  20. Computer-Mediated Education And Globalization - A Case Study On Cross-border Course "Globalization and Media"

    Directory of Open Access Journals (Sweden)

    Luyan Li

    2004-04-01

    Full Text Available This paper studies computer mediated education in social science, in particular, communication studies. As universities in the United States build closer relationships with foreign universities, cross-border education becomes more feasible with the assistance of web technology. To illustrate how this can be done, a trial course Globalization and Media is offered to students in both China and US from a US university. In the first part of the online tutorial, it is mainly instructor-based as the theories in media effects and globalization are introduced to the students. In the second part, the course becomes more application-based as students are requested to accomplish two tasks: firstly, study one of their own countries' major media institutions and share their findings in the online discussion board of the course website. After intense discussions of the different structures and functions of media institutions from the two countries, students are asked to conduct content analysis of a newspaper of their own countries over one common issue, e.g., the coverage of Iraq war. Their findings are again posted on the course discussion broad. Through these exercises students are able to see both sides and have a deeper understanding of the differences of media systems from a global angle. With computer mediated teaching, people from different countries can effectively learn from and exchange viewpoints with each other, without physically moving from one place to another. However, because only those who are computer literate and proficient in English could benefit from it, this may further deepen the gap of digital divide and exacerbate the dilution of cultures in the developing countries. Another concern is that because the instructor and the students are not in the same room, and may not even access to the course materials at the same time, although this provides convenience for the students to set their own time and pace, it also requires tremendous

  1. Gaps in studies of global health education: an empirical literature review

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2015-04-01

    Full Text Available Background: Global health has stimulated a lot of students and has attracted the interest of many faculties, thereby initiating the establishment of many academic programs on global health research and education. global health education reflects the increasing attention toward social accountability in medical education. Objective: This study aims to identify gaps in the studies on global health education. Design: A critical literature review of empirical studies was conducted using Boolean search techniques. Results: A total of 238 articles, including 16 reviews, were identified. There had been a boom in the numbers of studies on global health education since 2010. Four gaps were summarized. First, 94.6% of all studies on global health education were conducted in North American and European countries, of which 65.6% were carried out in the United States, followed by Canada (14.3% and the United Kingdom (9.2%. Only seven studies (2.9% were conducted in Asian countries, five (2.1% in Oceania, and two (0.8% in South American/Caribbean countries. A total of 154 studies (64.4% were qualitative studies and 64 studies (26.8% were quantitative studies. Second, elective courses and training or programs were the most frequently used approach for global health education. Third, there was a gap in the standardization of global health education. Finally, it was mainly targeted at medical students, residents, and doctors. It had not granted the demands for global health education of all students majoring in medicine-related studies. Conclusions: Global health education would be a potentially influential tool for achieving health equity, reducing health disparities, and also for future professional careers. It is the time to build and expand education in global health, especially among developing countries. Global health education should be integrated into primary medical education. Interdisciplinary approaches and interprofessional collaboration were

  2. The Clinical Research Office of the Endourological Society Percutaneous Nephrolithotomy Global Study

    DEFF Research Database (Denmark)

    Bucuras, Viorel; Gopalakrishnam, Ganesh; Wolf, J Stuart

    2012-01-01

    The study compared characteristics and outcomes in patients with solitary and bilateral kidneys who were treated with percutaneous nephrolithotomy (PCNL) in the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study.......The study compared characteristics and outcomes in patients with solitary and bilateral kidneys who were treated with percutaneous nephrolithotomy (PCNL) in the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study....

  3. Spectral identification and quantification of salts in the Atacama Desert

    Science.gov (United States)

    Harris, J. K.; Cousins, C. R.; Claire, M. W.

    2016-10-01

    Salt minerals are an important natural resource. The ability to quickly and remotely identify and quantify salt deposits and salt contaminated soils and sands is therefore a priority goal for the various industries and agencies that utilise salts. The advent of global hyperspectral imagery from instruments such as Hyperion on NASA's Earth-Observing 1 satellite has opened up a new source of data that can potentially be used for just this task. This study aims to assess the ability of Visible and Near Infrared (VNIR) spectroscopy to identify and quantify salt minerals through the use of spectral mixture analysis. The surface and near-surface soils of the Atacama Desert in Chile contain a variety of well-studied salts, which together with low cloud coverage, and high aridity, makes this region an ideal testbed for this technique. Two forms of spectral data ranging 0.35 - 2.5 μm were collected: laboratory spectra acquired using an ASD FieldSpec Pro instrument on samples from four locations in the Atacama desert known to have surface concentrations of sulfates, nitrates, chlorides and perchlorates; and images from the EO-1 satellite's Hyperion instrument taken over the same four locations. Mineral identifications and abundances were confirmed using quantitative XRD of the physical samples. Spectral endmembers were extracted from within the laboratory and Hyperion spectral datasets and together with additional spectral library endmembers fed into a linear mixture model. The resulting identification and abundances from both dataset types were verified against the sample XRD values. Issues of spectral scale, SNR and how different mineral spectra interact are considered, and the utility of VNIR spectroscopy and Hyperion in particular for mapping specific salt concentrations in desert environments is established. Overall, SMA was successful at estimating abundances of sulfate minerals, particularly calcium sulfate, from both hyperspectral image and laboratory sample spectra

  4. Experimental and theoretical studies of spectral alteration in ultrasonic waves resulting from nonlinear elastic response in rock

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, P.A.; McCall, K.R.; Meegan, G.D. Jr. [Los Alamos National Lab., NM (United States)

    1993-11-01

    Experiments in rock show a large nonlinear elastic wave response, far greater than that of gases, liquids and most other solids. The large response is attributed to structural defects in rock including microcracks and grain boundaries. In the earth, a large nonlinear response may be responsible for significant spectral alteration at amplitudes and distances currently considered to be well within the linear elastic regime.

  5. Study of old ecological hazards, oil seeps and contaminations using earth observation methods – spectral library for oil seep

    Directory of Open Access Journals (Sweden)

    Smejkalová Eva

    2017-03-01

    Full Text Available The possibilities of remote sensing techniques in the field of the Earth surface monitoring and protection specifically for the problems caused by petroleum contaminations, for the mapping of insufficiently plugged and abandoned old oil wells and for the analysis of onshore oil seeps are described. Explained is the methodology for analyzing and detection of potential hydrocarbon contaminations using the Earth observation in the area of interest in Slovakia (Korňa and in Czech Republic (Nesyt, mainly building and calibrating the spectral library for oil seeps. The acquisition of the in-situ field data (ASD, Cropscan spectroradiometers for this purpose, the successful building and verification of hydrocarbon spectral library, the application of hydrocarbon indexes and use of shift in red-edge part of electromagnetic spectra, the spectral analysis of input data are clarified in the paper. Described is approach which could innovate the routine methods for investigating the occurrence of hydrocarbons and can assist during the mapping and locating the potential oil seep sites. Important outcome is the successful establishment of a spectral library (database with calibration data suitable for further application in data classification for identifying the occurrence of hydrocarbons.

  6. EEG spectral phenotypes: heritability and association with marijuana and alcohol dependence in an American Indian community study.

    Science.gov (United States)

    Ehlers, Cindy L; Phillips, Evelyn; Gizer, Ian R; Gilder, David A; Wilhelmsen, Kirk C

    2010-01-15

    Native Americans have some of the highest rates of marijuana and alcohol use and abuse, yet neurobiological measures associated with dependence on these substances in this population remain unknown. The present investigation evaluated the heritability of spectral characteristics of the electroencephalogram (EEG) and their correlation with marijuana and alcohol dependence in an American Indian community. Participants (n=626) were evaluated for marijuana (MJ) and alcohol (ALC) dependence, as well as other psychiatric disorders. EEGs were collected from six cortical sites and spectral power determined in five frequency bands (delta 1.0-4.0 Hz, theta 4.0-7.5 Hz, alpha 7.5-12.0 Hz, low beta 12.0-20.0 Hz and high beta/gamma 20-50 Hz). The estimated heritability (h(2)) of the EEG phenotypes was calculated using SOLAR, and ranged from 0.16 to 0.67. Stepwise linear regression was used to detect correlations between MJ and ALC dependence and the spectral characteristics of the EEG using a model that took into account: age, gender, Native American Heritage (NAH) and a lifetime diagnosis of antisocial personality and/or conduct disorder (ASPD/CD). Increases in spectral power in the delta frequency range, were significantly correlated with gender (pEEG delta and high beta/gamma activity are correlated with MJ dependence and alcohol dependence, respectively, in this community sample of Native Americans. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  7. DFT study of the physicochemical characteristics and spectral behavior of new 8-substituted 1,3,7-trimethylxanthines

    Czech Academy of Sciences Publication Activity Database

    Stanchev, Stancho; Mitkov, J.; Georgieva, M.; Zlatkov, A.

    2013-01-01

    Roč. 113, č. 9 (2013), s. 1384-1393 ISSN 0020-7608 Institutional support: RVO:61388963 Keywords : caffeine derivates * quantum chemical properties * spectral properties * DFT methods Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.166, year: 2013

  8. Experimental and theoretical studies of spectral alteration in ultrasonic waves resulting from nonlinear elastic response in rock

    International Nuclear Information System (INIS)

    Johnson, P.A.; McCall, K.R.; Meegan, G.D. Jr.

    1993-01-01

    Experiments in rock show a large nonlinear elastic wave response, far greater than that of gases, liquids and most other solids. The large response is attributed to structural defects in rock including microcracks and grain boundaries. In the earth, a large nonlinear response may be responsible for significant spectral alteration at amplitudes and distances currently considered to be well within the linear elastic regime

  9. Improving classification accuracy of spectrally similar tree species: a complex case study in the Kruger National Park

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2009-07-01

    Full Text Available , sugar beet, sunflower, alfalfa. Digital Imaging Spectrometer – DAIS-7915 – 79 channel hyperspectral image. Spectral range from visible (0.4 µm) to thermal infrared (12.3 µm). Spatial resolution 3–20 m depending on the carrier aircraft altitude...

  10. A NEW MULTI-SPECTRAL THRESHOLD NORMALIZED DIFFERENCE WATER INDEX (MST-NDWI WATER EXTRACTION METHOD – A CASE STUDY IN YANHE WATERSHED

    Directory of Open Access Journals (Sweden)

    Y. Zhou

    2018-05-01

    Full Text Available Accurate remote sensing water extraction is one of the primary tasks of watershed ecological environment study. Since the Yanhe water system has typical characteristics of a small water volume and narrow river channel, which leads to the difficulty for conventional water extraction methods such as Normalized Difference Water Index (NDWI. A new Multi-Spectral Threshold segmentation of the NDWI (MST-NDWI water extraction method is proposed to achieve the accurate water extraction in Yanhe watershed. In the MST-NDWI method, the spectral characteristics of water bodies and typical backgrounds on the Landsat/TM images have been evaluated in Yanhe watershed. The multi-spectral thresholds (TM1, TM4, TM5 based on maximum-likelihood have been utilized before NDWI water extraction to realize segmentation for a division of built-up lands and small linear rivers. With the proposed method, a water map is extracted from the Landsat/TM images in 2010 in China. An accuracy assessment is conducted to compare the proposed method with the conventional water indexes such as NDWI, Modified NDWI (MNDWI, Enhanced Water Index (EWI, and Automated Water Extraction Index (AWEI. The result shows that the MST-NDWI method generates better water extraction accuracy in Yanhe watershed and can effectively diminish the confusing background objects compared to the conventional water indexes. The MST-NDWI method integrates NDWI and Multi-Spectral Threshold segmentation algorithms, with richer valuable information and remarkable results in accurate water extraction in Yanhe watershed.

  11. Spectroscopic studies of two spectral variants of light-harvesting complex 2 (LH2) from the photosynthetic purple sulfur bacterium Allochromatium vinosum.

    Science.gov (United States)

    Niedzwiedzki, Dariusz M; Bina, David; Picken, Nichola; Honkanen, Suvi; Blankenship, Robert E; Holten, Dewey; Cogdell, Richard J

    2012-09-01

    Two spectral forms of the peripheral light-harvesting complex (LH2) from the purple sulfur photosynthetic bacterium Allochromatium vinosum were purified and their photophysical properties characterized. The complexes contain bacteriochlorophyll a (BChl a) and multiple species of carotenoids. The composition of carotenoids depends on the light conditions applied during growth of the cultures. In addition, LH2 grown under high light has a noticeable split of the B800 absorption band. The influence of the change of carotenoid distribution as well as the spectral change of the excitonic absorption of the bacteriochlorophylls on the light-harvesting ability was studied using steady-state absorption, fluorescence and femtosecond time-resolved absorption at 77K. The results demonstrate that the change of the distribution of the carotenoids when cells were grown at low light adapts the absorptive properties of the complex to the light conditions and maintains maximum photon-capture performance. In addition, an explanation for the origin of the enigmatic split of the B800 absorption band is provided. This spectral splitting is also observed in LH2 complexes from other photosynthetic sulfur purple bacterial species. According to results obtained from transient absorption spectroscopy, the B800 band split originates from two spectral forms of the associated BChl a monomeric molecules bound within the same complex. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Spectral analysis and classification of igneous and metamorphic rocks of Hamedan region for remote sensing studies; using laboratory reflectance spectra (350-2500 nm)

    International Nuclear Information System (INIS)

    Rangzan, K.; Saki, A.; Hassanshahi, H.; Mojaradi, B.

    2012-01-01

    Reflectance spectrometry techniques with the integration of remote sensing data help us in identifying and mapping the phenomena on the earth. Using these techniques to discriminate the petrologic units independently and without knowing the spectral behavior of rocks along the electromagnetic wavelengths can not be so much useful. For the purposes of this study, 65 samples of igneous and metamorphic rocks from Hamedan region were collected and their spectra were measured using Fieldspec3 device in laboratory. The spectra were analyzed on the basis of absorption, position and shape. Petrographic analyses were used to interpret the absorption patterns as well. Then the spectra were classified according to spectral patterns. This measurement was done on both freshly cut and exposed surfaces of the samples and except a few samples, the two sets of spectra did not differ significantly. Finally, to evaluate the possibility of recognition of these targets, the responses of two hyper spectral and multispectral sensors were simulated from spectra representative of the spectral classes, showing that significant identification and classification of well exposed rocks are potentially possible using remote instruments providing high quality spectra. Also Aster simulation showed that a preliminary gross discrimination of rocks was however possible.

  13. A case study of global health at the university: implications for research and action

    Directory of Open Access Journals (Sweden)

    Andrew D. Pinto

    2014-08-01

    Full Text Available Background: Global health is increasingly a major focus of institutions in high-income countries. However, little work has been done to date to study the inner workings of global health at the university level. Academics may have competing objectives, with few mechanisms to coordinate efforts and pool resources. Objective: To conduct a case study of global health at Canada's largest health sciences university and to examine how its internal organization influences research and action. Design: We drew on existing inventories, annual reports, and websites to create an institutional map, identifying centers and departments using the terms ‘global health’ or ‘international health’ to describe their activities. We compiled a list of academics who self-identified as working in global or international health. We purposively sampled persons in leadership positions as key informants. One investigator carried out confidential, semi-structured interviews with 20 key informants. Interview notes were returned to participants for verification and then analyzed thematically by pairs of coders. Synthesis was conducted jointly. Results: More than 100 academics were identified as working in global health, situated in numerous institutions, centers, and departments. Global health academics interviewed shared a common sense of what global health means and the values that underpin such work. Most academics interviewed expressed frustration at the existing fragmentation and the lack of strategic direction, financial support, and recognition from the university. This hampered collaborative work and projects to tackle global health problems. Conclusions: The University of Toronto is not exceptional in facing such challenges, and our findings align with existing literature that describes factors that inhibit collaboration in global health work at universities. Global health academics based at universities may work in institutional siloes and this limits both

  14. A case study of global health at the university: implications for research and action.

    Science.gov (United States)

    Pinto, Andrew D; Cole, Donald C; ter Kuile, Aleida; Forman, Lisa; Rouleau, Katherine; Philpott, Jane; Pakes, Barry; Jackson, Suzanne; Muntaner, Carles

    2014-01-01

    Global health is increasingly a major focus of institutions in high-income countries. However, little work has been done to date to study the inner workings of global health at the university level. Academics may have competing objectives, with few mechanisms to coordinate efforts and pool resources. To conduct a case study of global health at Canada's largest health sciences university and to examine how its internal organization influences research and action. We drew on existing inventories, annual reports, and websites to create an institutional map, identifying centers and departments using the terms 'global health' or 'international health' to describe their activities. We compiled a list of academics who self-identified as working in global or international health. We purposively sampled persons in leadership positions as key informants. One investigator carried out confidential, semi-structured interviews with 20 key informants. Interview notes were returned to participants for verification and then analyzed thematically by pairs of coders. Synthesis was conducted jointly. More than 100 academics were identified as working in global health, situated in numerous institutions, centers, and departments. Global health academics interviewed shared a common sense of what global health means and the values that underpin such work. Most academics interviewed expressed frustration at the existing fragmentation and the lack of strategic direction, financial support, and recognition from the university. This hampered collaborative work and projects to tackle global health problems. The University of Toronto is not exceptional in facing such challenges, and our findings align with existing literature that describes factors that inhibit collaboration in global health work at universities. Global health academics based at universities may work in institutional siloes and this limits both internal and external collaboration. A number of solutions to address these

  15. Substitution dynamical systems spectral analysis

    CERN Document Server

    Queffélec, Martine

    2010-01-01

    This volume mainly deals with the dynamics of finitely valued sequences, and more specifically, of sequences generated by substitutions and automata. Those sequences demonstrate fairly simple combinatorical and arithmetical properties and naturally appear in various domains. As the title suggests, the aim of the initial version of this book was the spectral study of the associated dynamical systems: the first chapters consisted in a detailed introduction to the mathematical notions involved, and the description of the spectral invariants followed in the closing chapters. This approach, combined with new material added to the new edition, results in a nearly self-contained book on the subject. New tools - which have also proven helpful in other contexts - had to be developed for this study. Moreover, its findings can be concretely applied, the method providing an algorithm to exhibit the spectral measures and the spectral multiplicity, as is demonstrated in several examples. Beyond this advanced analysis, many...

  16. Study of the spectral width of intermode beats and optical spectrum of an actively mode-locked three-mirror semiconductor laser

    International Nuclear Information System (INIS)

    Zakharyash, Valerii F; Kashirsky, Aleksandr V; Klementyev, Vasilii M; Kuznetsov, Sergei A; Pivtsov, V S

    2005-01-01

    Various oscillation regimes of an actively mode-locked semiconductor laser are studied experimentally. Two types of regimes are found in which the minimal spectral width (∼3.5 kHz) of intermode beats is achieved. The width of the optical spectrum of modes is studied as a function of their locking and the feedback coefficients. The maximum width of the spectrum is ∼3.7 THz. (control of laser radiation parameters)

  17. A study of the chilean vertical network through global geopotential models and the cnes cls 2011 global mean sea surface

    Directory of Open Access Journals (Sweden)

    Henry Montecino Castro

    Full Text Available Most aspects related to the horizontal component of the Geocentric Reference System for the Americas (SIRGAS have been solved. However, in the case of the vertical component there are still aspects of definition, national realizations and continental unification still not accomplished. Chile is no exception; due to its particular geographic characteristics, a number of tide gauges (TG had to be installed in the coast from which the leveling lines that compose the Chilean Vertical Network (CHVN were established. This study explored the offsets of the CHVN by two different approaches; one geodetic and one oceanographic. In the first approach, the offsets were obtained in relation to the following Global Geopotential Models (GGM: the satellite-only model (unbiased GO_CONS_gcf_2_tim_r3 derived from GOCE satellite mission; EGM2008 (combined-biased; and GOEGM08, combining information from the GO_CONS_gcf_2_tim_r3 in long wavelengths (n max~200 with the mean/short wavelengths of EGM2008 (n>200. In the oceanographic method, we used the CNES CLS 2011 Global Mean Sea surface and EIGEN_GRACE_5C GGM to obtain the values of MDT at the different TG. We also evaluated the CHVN in relation to different GGMs. The results showed consistency between the values obtained by the two methods at the TG of Valparaíso and Puerto Chacabuco. In terms of the evaluation of the GGM, GOEGM08 produced the best results.

  18. Preliminary study on the differentiation between parapelvic cyst and hydronephrosis with non-calculous using only pre-contrast dual-energy spectral CT scans

    Science.gov (United States)

    Han, Dong; Ma, Guangming; Wei, Lequn; Ren, Chenglong; Zhou, Jieli; Shen, Chen

    2017-01-01

    Objective: To investigate the value of using the quantitative parameters from only the pre-contrast dual-energy spectral CT imaging for distinguishing between parapelvic cyst and hydronephrosis with non-calculous (HNC). Methods: This retrospective study was approved by the institutional review board. 28 patients with parapelvic cyst and 24 patients with HNC who underwent standard pre-contrast and multiphase contrast-enhanced dual-energy spectral CT imaging were retrospectively identified. The parapelvic cyst and HNC were identified using the contrast-enhanced scans, and their CT number in the 70-keV monochromatic images, effective atomic number (Zeff), iodine concentration (IC) and water concentration in the pre-contrast images were measured. The slope of the spectral curve (λ) was calculated. The difference in the measurements between parapelvic cyst and HNC was statistically analyzed using SPSS® v. 19.0 (IBM Corp., New York, NY; formerly SPSS Inc., Chicago, IL) statistical software. Receiver-operating characteristic analysis was performed to assess the diagnostic performance. Results: The CT numbers in the 70-keV images, Zeff and IC values were statistically different between parapelvic cyst and HNC (all p  0.05). Conclusion: The quantitative parameters obtained in the pre-contrast dual-energy spectral CT imaging may be used to differentiate between parapelvic cyst and HNC. Advances in knowledge: The pre-contrast dual-energy spectral CT scans may be used to screen parapelvic cysts for patients who are asymptomatic, thereby avoiding contrast-enhanced CT or CT urography examination for these patients to reduce ionizing radiation dose and contrast dose. PMID:28281789

  19. A pilot study using low-dose Spectral CT and ASIR (Adaptive Statistical Iterative Reconstruction) algorithm to diagnose solitary pulmonary nodules.

    Science.gov (United States)

    Xiao, Huijuan; Liu, Yihe; Tan, Hongna; Liang, Pan; Wang, Bo; Su, Lei; Wang, Suya; Gao, Jianbo

    2015-11-17

    Lung cancer is the most common cancer which has the highest mortality rate. With the development of computed tomography (CT) techniques, the case detection rates of solitary pulmonary nodules (SPN) has constantly increased and the diagnosis accuracy of SPN has remained a hot topic in clinical and imaging diagnosis. The aim of this study was to evaluate the combination of low-dose spectral CT and ASIR (Adaptive Statistical Iterative Reconstruction) algorithm in the diagnosis of solitary pulmonary nodules (SPN). 62 patients with SPN (42 cases of benign SPN and 20 cases of malignant SPN, pathology confirmed) were scanned by spectral CT with a dual-phase contrast-enhanced method. The iodine and water concentration (IC and WC) of the lesion and the artery in the image that had the same density were measured by the GSI (Gemstone Spectral Imaging) software. The normalized iodine and water concentration (NIC and NWC) of the lesion and the normalized iodine and water concentration difference (ICD and WCD) between the arterial and venous phases (AP and VP) were also calculated. The spectral HU (Hounsfield Unit ) curve was divided into 3 sections based on the energy (40-70, 70-100 and 100-140 keV) and the slopes (λHU) in both phases were calculated. The ICAP, ICVP, WCAP and WCVP, NIC and NWC, and the λHU in benign and malignant SPN were compared by independent sample t-test. The iodine related parameters (ICAP, ICVP, NICAP, NICVP, and the ICD) of malignant SPN were significantly higher than that of benign SPN (t = 3.310, 1.330, 2.388, 1.669 and 3.251, respectively, P 0.05). The iodine related parameters and the slope of spectral curve are useful markers to distinguish the benign from the malignant lung diseases, and its application is extremely feasible in clinical applications.

  20. Global Simulation of Bioenergy Crop Productivity: Analytical framework and Case Study for Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Nair, S. Surendran [University of Tennessee, Knoxville (UTK); Nichols, Jeff A. {Cyber Sciences} [ORNL; Post, Wilfred M [ORNL; Wang, Dali [ORNL; Wullschleger, Stan D [ORNL; Kline, Keith L [ORNL; Wei, Yaxing [ORNL; Singh, Nagendra [ORNL; Kang, Shujiang [ORNL

    2014-01-01

    Contemporary global assessments of the deployment potential and sustainability aspects of biofuel crops lack quantitative details. This paper describes an analytical framework capable of meeting the challenges associated with global scale agro-ecosystem modeling. We designed a modeling platform for bioenergy crops, consisting of five major components: (i) standardized global natural resources and management data sets, (ii) global simulation unit and management scenarios, (iii) model calibration and validation, (iv) high-performance computing (HPC) modeling, and (v) simulation output processing and analysis. A case study with the HPC- Environmental Policy Integrated Climate model (HPC-EPIC) to simulate a perennial bioenergy crop, switchgrass (Panicum virgatum L.) and global biomass feedstock analysis on grassland demonstrates the application of this platform. The results illustrate biomass feedstock variability of switchgrass and provide insights on how the modeling platform can be expanded to better assess sustainable production criteria and other biomass crops. Feedstock potentials on global grasslands and within different countries are also shown. Future efforts involve developing databases of productivity, implementing global simulations for other bioenergy crops (e.g. miscanthus, energycane and agave), and assessing environmental impacts under various management regimes. We anticipated this platform will provide an exemplary tool and assessment data for international communities to conduct global analysis of biofuel biomass feedstocks and sustainability.

  1. Spectral gamuts and spectral gamut mapping

    Science.gov (United States)

    Rosen, Mitchell R.; Derhak, Maxim W.

    2006-01-01

    All imaging devices have two gamuts: the stimulus gamut and the response gamut. The response gamut of a print engine is typically described in CIE colorimetry units, a system derived to quantify human color response. More fundamental than colorimetric gamuts are spectral gamuts, based on radiance, reflectance or transmittance units. Spectral gamuts depend on the physics of light or on how materials interact with light and do not involve the human's photoreceptor integration or brain processing. Methods for visualizing a spectral gamut raise challenges as do considerations of how to utilize such a data-set for producing superior color reproductions. Recent work has described a transformation of spectra reduced to 6-dimensions called LabPQR. LabPQR was designed as a hybrid space with three explicit colorimetric axes and three additional spectral reconstruction axes. In this paper spectral gamuts are discussed making use of LabPQR. Also, spectral gamut mapping is considered in light of the colorimetric-spectral duality of the LabPQR space.

  2. The Cultural Challenges of Managing Global Project Teams: A Study of Brazilian Multinationals

    Directory of Open Access Journals (Sweden)

    Ivete Rodrigues

    2013-04-01

    Full Text Available The internationalization of Brazilian companies brings a new reality: the need for implementation of global projects that bring, in turn, the challenge of managing multicultural teams. Since this is a recent phenomenon with little theoretical development, this study sought to understand the relationships between cultural characteristics and management teams of global projects in Brazilian multinationals. To carry this discussion forward, we studied six cases of Brazilian multinational companies, with the aim of deepening the understanding of the management of global teams, involving the planning, deployment, development and management of human resources. Among the projects studied, it was found that there is very little concern with the specific issue of multiculturalism and little inter-cultural incentive to the development of team members, which ends up hindering the construction of a global mindset, important for the Brazilian multinational companies to perform successfully abroad. Faced with this situation, each of the managerial processes mentioned were presented with a number of actions to be undertaken by the project manager in three different dimensions: the project itself, the organization and the global environment. The work contributes, thus, to enable Brazilian multinational companies to manage their global teams in order to maximize the advantages of global teams, such as increased creativity and innovative capacity, but avoid the problems that multiculturalism can bring, ranging from conflicts between people to project failure.

  3. Studying the extinction coefficient due to aerosol particles at different spectral bands in some regions at great Cairo

    International Nuclear Information System (INIS)

    Shaltout, M.A. Mosalam; Tadros, M.T.Y.; El-Metwally, M.

    2000-01-01

    Extinction coefficient due to aerosol has been estimated by Pyrheliometric and Gorgie type Actinometric measurements in the industrial, urban areas and compared with agricultural areas. The measurements distributed over one year from June 1992 to May 1993 were made under clear sky for five spectral bands. The results show two maxima in hot wet and spring months and minimum in winter months, but there is a fluctuation in urban area. Diurnal variations show maximum at noon especially in the industrial area. Level of extinction coefficient in the industrial and urban area is greater that that of the agricultural area, except for hot wet months is due to the increase of water vapor content in agricultural area. Spectral distribution of the extinction coefficient decreases monotonically with wavelength. Size of particles in industrial area is greater than in urban and agricultural areas. The temperature and water vapor content have important rules in increasing the extinction coefficient of aerosols. (Author)

  4. Study of Shortwave Spectra in Fully 3D Environment: Synergy Between Scanning Radars and Spectral Radiation Measurements

    Science.gov (United States)

    Wiscombe, Warren J.

    2012-01-01

    The main theme for our research is the understanding and closure of the surface spectral shortwave radiation problem in fully 3D cloud situations by combining the new ARM scanning radars, shortwave spectrometers, and microwave radiometers with the arsenal of radiative transfer tools developed by our group. In particular, we define first a large number of cloudy test cases spanning all 3D possibilities not just the customary uniform-overcast ones. Second, for each case, we define a "Best Estimate of Clouds That Affect Shortwave Radiation" using all relevant ARM instruments, notably the new scanning radars, and contribute this to the ARM Archive. Third, we test the ASR-signature radiative transfer model RRTMG_SW for those cases, focusing on the near-IR because of long-standing problems in this spectral region, and work with the developers to improve RRTMG_SW in order to increase its penetration into the modeling community.

  5. EEG spectral phenotypes: heritability and association with marijuana and alcohol dependence in an American Indian community study

    OpenAIRE

    Ehlers, Cindy L.; Phillips, Evelyn; Gizer, Ian R.; Gilder, David A.; Wilhelmsen, Kirk C.

    2009-01-01

    Native Americans have some of the highest rates of marijuana and alcohol use and abuse, yet neurobiological measures associated with dependence on these substances in this population remain unknown. The present investigation evaluated the heritability of spectral characteristics of the electroencephalogram (EEG) and their correlation with marijuana and alcohol dependence in an American Indian community. Participants (n=626) were evaluated for marijuana (MJ) and alcohol (ALC) dependence, as we...

  6. INFORMATION TECHNOLOGY STUDY ADAPTATSYONNOY ABILITIES CARDIOVASCULAR SYSTEM FOR PHYSICAL EXEMENATION BY MORPHOLOGICAL, TEMPORAL AND SPECTRAL ANALYSIS OSCILLOGRAMS

    OpenAIRE

    V. P. Martsenyuk; D. V. Vakulenko; L. O. Vakulenko

    2015-01-01

    Offer Author Information Technology morphological, temporal and spectral analysis of waveforms (recorded at rest and after exercise), the introduction of analytical treated for clinical interpretation of the results, evaluation and decision-making to doctors significantly increases the information content of the procedure of blood pressure measurement. Can be used for early detection and prenosological premorbid state and functional reserve of the circulatory system, help more effectively to ...

  7. INFORMATION TECHNOLOGY STUDY ADAPTATSYONNOY ABILITIES CARDIOVASCULAR SYSTEM FOR PHYSICAL EXEMENATION BY MORPHOLOGICAL, TEMPORAL AND SPECTRAL ANALYSIS OSCILLOGRAMS

    Directory of Open Access Journals (Sweden)

    V. P. Martsenyuk

    2015-12-01

    Full Text Available Offer Author Information Technology morphological, temporal and spectral analysis of waveforms (recorded at rest and after exercise, the introduction of analytical treated for clinical interpretation of the results, evaluation and decision-making to doctors significantly increases the information content of the procedure of blood pressure measurement. Can be used for early detection and prenosological premorbid state and functional reserve of the circulatory system, help more effectively to plan preventive, diagnostic and therapeutic process.

  8. Structural, optical absorption and photoluminescence spectral studies of Sm3+ ions in Alkaline-Earth Boro Tellurite glasses

    Science.gov (United States)

    Siva Rama Krishna Reddy, K.; Swapna, K.; Mahamuda, Sk.; Venkateswarlu, M.; Srinivas Prasad, M. V. V. K.; Rao, A. S.; Prakash, G. Vijaya

    2018-05-01

    Sm3+ ions doped Alkaline-Earth Boro Tellurite (AEBT) glasses were prepared by using conventional melt quenching technique and characterized using the spectroscopic techniques such as FT-IR, optical absorption, emission and decay spectral measurements to understand their utility in optoelectronic devices. From absorption spectra, the bonding parameters, nephelauxetic ratios were determined to know the nature of bonding between Sm3+ ions and its surrounding ligands. From the measured oscillator strengths, the Judd-Ofelt (J-O) intensity parameters were evaluated and in turn used to estimate various radiative parameters for the fluorescent levels of Sm3+ ions in AEBT glasses. The PL spectra of Sm3+ ions exhibit three emission bands corresponding to the transitions 4G5/2 → 6H5/2, 6H7/2 and 6H9/2 in the visible region for which the emission cross-sections and branching ratios were evaluated. The decay spectral profiles measured for 4G5/2 → 6H7/2 transition showed single exponential for lower concentration and non-exponential for higher concentration of doped rare earth ion in the as prepared glasses. Conversion of decay spectral profiles from single to non-exponential have been analyzed using Inokuti-Hirayama (I-H) model to understand the energy transfer mechanism involved in the decay process. CIE Chromaticity coordinates were measured using emission spectral data to identify the exact region of emission from the as-prepared glasses. From the evaluated radiative parameters, emission cross-sections and quantum efficiencies, it was observed that AEBT glass with 1 mol% of Sm3+ ions is more suitable for designing optoelectronic devices.

  9. Stopped-flow studies of spectral changes in bilirubin-human serum albumin following an alkaline pH jump and following binding of bilirubin

    DEFF Research Database (Denmark)

    Honoré, B

    1987-01-01

    A stopped-flow technique was used to study the spectral changes occurring in bilirubin-albumin following a pH jump as well as following binding of bilirubin at 25 degrees C. The changes were studied in two wavelength ranges, 280-310 nm (tyrosine residues) and 400-510 nm (bound bilirubin). The cha......A stopped-flow technique was used to study the spectral changes occurring in bilirubin-albumin following a pH jump as well as following binding of bilirubin at 25 degrees C. The changes were studied in two wavelength ranges, 280-310 nm (tyrosine residues) and 400-510 nm (bound bilirubin......). The changes were analyzed according to a scheme of consecutive unimolecular reactions. Spectral monitoring of a pH jump from 11.3 to 11.8 reveals that the bilirubin-albumin complex changes its structure in several steps. The UV absorption spectra show that 3.8 tyrosine residues ionize in the first step, 2...

  10. A Deep Chandra ACIS Study of NGC 4151. III. The Line Emission and Spectral Analysis of the Ionization Cone

    Science.gov (United States)

    Wang, Junfeng; Fabbiano, Giuseppina; Elvis, Martin; Risaliti, Guido; Karovska, Margarita; Zezas, Andreas; Mundell, Carole G.; Dumas, Gaelle; Schinnerer, Eva

    2011-11-01

    This paper is the third in a series in which we present deep Chandra ACIS-S imaging spectroscopy of the Seyfert 1 galaxy NGC 4151, devoted to study its complex circumnuclear X-ray emission. Emission features in the soft X-ray spectrum of the bright extended emission (L 0.3-2 keV ~ 1040 erg s-1) at r > 130 pc (2'') are consistent with blended brighter O VII, O VIII, and Ne IX lines seen in the Chandra HETGS and XMM-Newton RGS spectra below 2 keV. We construct emission line images of these features and find good morphological correlations with the narrow-line region clouds mapped in [O III] λ5007. Self-consistent photoionization models provide good descriptions of the spectra of the large-scale emission, as well as resolved structures, supporting the dominant role of nuclear photoionization, although displacement of optical and X-ray features implies a more complex medium. Collisionally ionized emission is estimated to be lsim12% of the extended emission. Presence of both low- and high-ionization spectral components and extended emission in the X-ray image perpendicular to the bicone indicates leakage of nuclear ionization, likely filtered through warm absorbers, instead of being blocked by a continuous obscuring torus. The ratios of [O III]/soft X-ray flux are approximately constant (~15) for the 1.5 kpc radius spanned by these measurements, indicating similar relative contributions from the low- and high-ionization gas phases at different radial distances from the nucleus. If the [O III] and X-ray emission arise from a single photoionized medium, this further implies an outflow with a wind-like density profile. Using spatially resolved X-ray features, we estimate that the mass outflow rate in NGC 4151 is ~2 M ⊙ yr-1 at 130 pc and the kinematic power of the ionized outflow is 1.7 × 1041 erg s-1, approximately 0.3% of the bolometric luminosity of the active nucleus in NGC 4151.

  11. A global benchmark study using affinity-based biosensors

    NARCIS (Netherlands)

    Rich, Rebecca L.; Papalia, Giusseppe A.; Krishnamoorthy, G.; Beusink, J.B.; Pak, Brian J.; Myszka, David G.; more, more

    2009-01-01

    To explore the variability in biosensor studies, 150 participants from 20 countries were given the same protein samples and asked to determine kinetic rate constants for the interaction. We chose a protein system that was amenable to analysis using different biosensor platforms as well as by users

  12. Amylolytic studies of pleurotus tuber-regium | Monago | Global ...

    African Journals Online (AJOL)

    The alpha amylase of the sclerotium of Pleurotus tuber-regium was studied. The enzyme was purified from the fresh sclerotium through dialysis, ammonium sulphate fractionation and column chromatography of CM sephadex. The enzyme showed 70% of it's optimal activity between p.H 4.0 to 8.0. Acid and thermal stability ...

  13. Global perspectives on methodology in the study of religion

    DEFF Research Database (Denmark)

    Geertz, Armin W.

    2013-01-01

    Dette kapitel er en genudgivelse af en artikel som blev publiceret i 2000 med samme titel i Method and Theory in the Study of Religion. Kapitlet er genudgivet i anledning af tidsskriftets 25 års jubilæum og blev valgt som et eksempel blandt mange til en "best of"-publikation. Men de valgte artikl...

  14. Global, regional, and national incidence and mortality for HIV, tuberculosis, and malaria during 1990-2013 : a systematic analysis for the Global Burden of Disease Study 2013

    NARCIS (Netherlands)

    Murray, Christopher J. L.; Ortblad, Katrina F.; Guinovart, Caterina; Lim, Stephen S.; Wolock, Timothy M.; Roberts, D. Allen; Dansereau, Emily A.; Graetz, Nicholas; Barber, Ryan M.; Brown, Jonathan C.; Wang, Haidong; Duber, Herbert C.; Naghavi, Mohsen; Dicker, Daniel; Dandona, Lalit; Salomon, Joshua A.; Heuton, Kyle R.; Foreman, Kyle; Phillips, David E.; Fleming, Thomas D.; Flaxman, Abraham D.; Phillips, Bryan K.; Johnson, Elizabeth K.; Coggeshall, Megan S.; Abd-Allah, Foad; Abera, Semaw Ferede; Abraham, Jerry P.; Abubakar, Ibrahim; Abu-Raddad, Laith J.; Abu-Rmeileh, Niveen Me; Achoki, Tom; Adeyemo, Austine Olufemi; Adou, Arsene Kouablan; Adsuar, Jose C.; Agardh, Emilie Elisabet; Akena, Dickens; Al Kahbouri, Mazin J.; Alasfoor, Deena; Albittar, Mohammed I.; Alcala-Cerra, Gabriel; Angel Alegretti, Miguel; Alemu, Zewdie Aderaw; Alfonso-Cristancho, Rafael; Alhabib, Samia; Ali, Raghib; Alla, Francois; Allen, Peter J.; Alsharif, Ubai; Alvarez, Elena; Alvis-Guzman, Nelson; Amankwaa, Adansi A.; Amare, Azmeraw T.; Amini, Hassan; Ammar, Walid; Anderson, Benjamin O.; Antonio, Carl Abelardo T.; Anwari, Palwasha; Arnlov, Johan; Arsenijevic, Valentina S. Arsic; Artaman, Ali; Asghar, Rana J.; Assadi, Reza; Atkins, Lydia S.; Badawi, Alaa; Balakrishnan, Kalpana; Banerjee, Amitava; Basu, Sanjay; Beardsley, Justin; Bekele, Tolesa; Bell, Michelle L.; Bernabe, Eduardo; Beyene, Tariku Jibat; Bhala, Neeraj; Bhalla, Ashish; Bhutta, Zulfiqar A.; Bin Abdulhak, Aref; Binagwaho, Agnes; Blore, Jed D.; Basara, Berrak Bora; Bose, Dipan; Brainin, Michael; Breitborde, Nicholas; Castaneda-Orjuela, Carlos A.; Catala-Lopez, Ferran; Chadha, Vineet K.; Chang, Jung-Chen; Chiang, Peggy Pei-Chia; Chuang, Ting-Wu; Colomar, Mercedes; Cooper, Leslie Trumbull; Cooper, Cyrus; Courville, Karen J.; Cowie, Benjamin C.; Criqui, Michael H.; Dandona, Rakhi; Dayama, Anand; De Leo, Diego; Degenhardt, Louisa; Del Pozo-Cruz, Borja; Deribe, Kebede; Des Jarlais, Don C.; Dessalegn, Muluken; Dharmaratne, Samath D.; Dilmen, Ugur; Ding, Eric L.; Driscoll, Tim R.; Durrani, Adnan M.; Ellenbogen, Richard G.; Ermakov, Sergey Petrovich; Esteghamati, Alireza; Faraon, Emerito Jose A.; Farzadfar, Farshad; Fereshtehnejad, Seyed-Mohammad; Fijabi, Daniel Obadare; Forouzanfar, Mohammad H.; Paleo, Urbano Fra; Gaffikin, Lynne; Gamkrelidze, Amiran; Gankpe, Fortune Gbetoho; Geleijnse, Johanna M.; Gessner, Bradford D.; Gibney, Katherine B.; Ginawi, Ibrahim Abdelmageem Mohamed; Glaser, Elizabeth L.; Gona, Philimon; Goto, Atsushi; Gouda, Hebe N.; Gugnani, Harish Chander; Gupta, Rajeev; Gupta, Rahul; Hafezi-Nejad, Nima; Hamadeh, Randah Ribhi; Hammami, Mouhanad; Hankey, Graeme J.; Harb, Hilda L.; Maria Haro, Josep; Havmoeller, Rasmus; Hay, Simon I.; Hedayati, Mohammad T.; Heredia Pi, Ileana B.; Hoek, Hans W.; Hornberger, John C.; Hosgood, H. Dean; Hotez, Peter J.; Hoy, Damian G.; Huang, John J.; Iburg, Kim M.; Idrisov, Bulat T.; Innos, Kaire; Jacobsen, Kathryn H.; Jeemon, Panniyammakal; Jensen, Paul N.; Jha, Vivekanand; Jiang, Guohong; Jonas, Jost B.; Juel, Knud; Kan, Haidong; Kankindi, Ida; Karam, Nadim E.; Karch, Andre; Karema, Corine Kakizi; Kaul, Anil; Kawakami, Norito; Kazi, Dhruv S.; Kemp, Andrew H.; Kengne, Andre Pascal; Keren, Andre; Kereselidze, Maia; Khader, Yousef Saleh; Khalifa, Shams Eldin Ali Hassan; Khan, Ejaz Ahmed; Khang, Young-Ho; Khonelidze, Irma; Kinfu, Yohannes; Kinge, Jonas M.; Knibbs, Luke; Kokubo, Yoshihiro; Kosen, S.; Defo, Barthelemy Kuate; Kulkarni, Veena S.; Kulkarni, Chanda; Kumar, Kaushalendra; Kumar, Ravi B.; Kumar, G. Anil; Kwan, Gene F.; Lai, Taavi; Balaji, Arjun Lakshmana; Lam, Hilton; Lan, Qing; Lansingh, Van C.; Larson, Heidi J.; Larsson, Anders; Lee, Jong-Tae; Leigh, James; Leinsalu, Mall; Leung, Ricky; Li, Yichong; Li, Yongmei; Ferreira De Lima, Graca Maria; Lin, Hsien-Ho; Lipshultz, Steven E.; Liu, Shiwei; Liu, Yang; Lloyd, Belinda K.; Lotufo, Paulo A.; Pedro Machado, Vasco Manuel; Maclachlan, Jennifer H.; Magis-Rodriguez, Carlos; Majdan, Marek; Mapoma, Christopher Chabila; Marcenes, Wagner; Barrieotos Marzan, Melvin; Masci, Joseph R.; Mashal, Mohammad Taufiq; Mason-Jones, Amanda J.; Mayosi, Bongani M.; Mazorodze, Tasara T.; Mckay, Abigail Cecilia; Meaney, Peter A.; Mehndiratta, Man Mohan; Mejia-Rodriguez, Fabiola; Melaku, Yohannes Adama; Memish, Ziad A.; Mendoza, Walter; Miller, Ted R.; Mills, Edward J.; Mohammad, Karzan Abdulmuhsin; Mokdad, Ali H.; Mola, Glen Liddell; Monasta, Lorenzo; Montico, Marcella; Moore, Ami R.; Mori, Rintaro; Moturi, Wilkister Nyaora; Mukaigawara, Mitsuru; Murthy, Kinnari S.; Naheed, Aliya; Naidoo, Kovin S.; Naldi, Luigi; Nangia, Vinay; Narayan, K. M. Venkat; Nash, Denis; Nejjari, Chakib; Nelson, Robert G.; Neupane, Sudan Prasad; Newton, Charles R.; Ng, Marie; Nisar, Muhammad Imran; Nolte, Sandra; Norheim, Ole F.; Nowaseb, Vincent; Nyakarahuka, Luke; Oh, In-Hwan; Ohkubo, Takayoshi; Olusanya, Bolajoko O.; Omer, Saad B.; Opio, John Nelson; Orisakwe, Orish Ebere; Pandian, Jeyaraj D.; Papachristou, Christina; Paternina Caicedo, Angel J.; Patten, Scott B.; Paul, Vinod K.; Pavlin, Boris Igor; Pearce, Neil; Pereira, David M.; Pervaiz, Aslam; Pesudovs, Konrad; Petzold, Max; Pourmalek, Farshad; Qato, Dima; Quezada, Amado D.; Quistberg, D. Alex; Rafay, Anwar; Rahimi, Kazem; Rahimi-Movaghar, Vafa; Rahman, Sajjad Ur; Raju, Murugesan; Rana, Saleem M.; Razavi, Homie; Reilly, Robert Quentin; Remuzzi, Giuseppe; Richardus, Jan Hendrik; Ronfani, Luca; Roy, Nobhojit; Sabin, Nsanzimana; Saeedi, Mohammad Yahya; Sahraian, Mohammad Ali; Samonte, Genesis May J.; Sawhney, Monika; Schneider, Ione J. C.; Schwebel, David C.; Seedat, Soraya; Sepanlou, Sadaf G.; Servan-Mori, Edson E.; Sheikhbahaei, Sara; Shibuya, Kenji; Shin, Hwashin Hyun; Shiue, Ivy; Shivakoti, Rupak; Sigfusdottir, Inga Dora; Silberberg, Donald H.; Silva, Andrea P.; Simard, Edgar P.; Singh, Jasvinder A.; Skirbekk, Vegard; Sliwa, Karen; Soneji, Samir; Soshnikov, Sergey S.; Sreeramareddy, Chandrashekhar T.; Stathopoulou, Vasiliki Kalliopi; Stroumpoulis, Konstantinos; Swaminathan, Soumya; Sykes, Bryan L.; Tabb, Karen M.; Talongwa, Roberto Tchio; Tenkorang, Eric Yeboah; Terkawi, Abdullah Sulieman; Thomson, Alan J.; Thorne-Lyman, Andrew L.; Towbin, Jeffrey A.; Traebert, Jefferson; Tran, Bach X.; Dimbuene, Zacharie Tsala; Tsilimbaris, Miltiadis; Uchendu, Uche S.; Ukwaja, Kingsley N.; Uzun, Selen Begum; Vallely, Andrew J.; Vasankari, Tommi J.; Venketasubramanian, N.; Violante, Francesco S.; Vlassov, Vasiliy Victorovich; Vollset, Stein Emil; Waller, Stephen; Wallin, Mitchell T.; Wang, Linhong; Wang, XiaoRong; Wang, Yanping; Weichenthal, Scott; Weiderpass, Elisabete; Weintraub, Robert G.; Westerman, Ronny; White, Richard A.; Wilkinson, James D.; Williams, Thomas Neil; Woldeyohannes, Solomon Meseret; Wong, John Q.; Xu, Gelin; Yang, Yong C.; Yano, Yuichiro; Yentur, Gokalp Kadri; Yip, Paul; Yonemoto, Naohiro; Yoon, Seok-Jun; Younis, Mustafa; Yu, Chuanhua; Jin, Kim Yun; Zaki, Maysaa El Sayed; Zhao, Yong; Zheng, Yingfeng; Zhou, Maigeng; Zhu, Jun; Zou, Xiao Nong; Lopez, Alan D.; Vos, Theo

    2014-01-01

    Background The Millennium Declaration in 2000 brought special global attention to HIV, tuberculosis, and malaria through the formulation of Millennium Development Goal (MDG) 6. The Global Burden of Disease 2013 study provides a consistent and comprehensive approach to disease estimation for between

  15. Contrast-enhanced spectral mammography in recalls from the Dutch breast cancer screening program : validation of results in a large multireader, multicase study

    OpenAIRE

    Lalji, U C; Houben, I P L; Prevos, R; Gommers, S; van Goethem, M; Vanwetswinkel, S; Pijnappel, R; Steeman, R; Frotscher, C; Mok, W; Nelemans, P; Smidt, M L; Beets-Tan, R G; Wildberger, J E; Lobbes, M B I

    2016-01-01

    OBJECTIVES: Contrast-enhanced spectral mammography (CESM) is a promising problem-solving tool in women referred from a breast cancer screening program. We aimed to study the validity of preliminary results of CESM using a larger panel of radiologists with different levels of CESM experience. METHODS: All women referred from the Dutch breast cancer screening program were eligible for CESM. 199 consecutive cases were viewed by ten radiologists. Four had extensive CESM experience, three had no C...

  16. Empirical Studies on the Use of Social Software in Global Software Development - a Systematic Mapping Study

    DEFF Research Database (Denmark)

    Giuffrida, Rosalba; Dittrich, Yvonne

    2013-01-01

    of empirical studies on the usage of SoSo are available in related fields, there exists no comprehensive overview of what has been investigated to date across them. Objective: The aim of this review is to map empirical studies on the usage of SoSo in Software Engineering projects and in distributed teams...... for collaborative work, fostering awareness, knowledge management and coordination among team members. Contrary to the evident high importance of the social aspects offered by SoSo, socialization is not the most important usage reported. Conclusions: This review reports how SoSo is used in GSD and how it is capable...... of supporting GSD teams. Four emerging themes in global software engineering were identified: the appropriation and development of usage structures; understanding how an ecology of communication channels and tools are used by teams; the role played by SoSo either as a subtext or as an explicit goal; and finally...

  17. IS supported service work: a case study of global certification

    OpenAIRE

    Berntsen, Kirsti Elisabeth

    2011-01-01

    The thesis approaches the issue of IS support for service work, understood as distributed knowledge work taking place as a negotiation between diverse interests. It is based on an ethnographically inspired, longitudinal case study of certification auditing according to a formal generic standard. A handful of certification auditors are followed closely, periodically and comprehensively over three years. Observations are combined with interviews of subjects and colleagues, added by exploration ...

  18. The global burden of viral hepatitis from 1990 to 2013: findings from the Global Burden of Disease Study 2013

    Science.gov (United States)

    Stanaway, Jeffrey D; Flaxman, Abraham D; Naghavi, Mohsen; Fitzmaurice, Christina; Vos, Theo; Abubakar, Ibrahim; Abu-Raddad, Laith J; Assadi, Reza; Bhala, Neeraj; Cowie, Benjamin; Forouzanfour, Mohammad H; Groeger, Justina; Hanafiah, Khayriyyah Mohd; Jacobsen, Kathryn H; James, Spencer L; MacLachlan, Jennifer; Malekzadeh, Reza; Martin, Natasha K; Mokdad, Ali A; Mokdad, Ali H; Murray, Christopher J L; Plass, Dietrich; Rana, Saleem; Rein, David B; Richardus, Jan Hendrik; Sanabria, Juan; Saylan, Mete; Shahraz, Saeid; So, Samuel; Vlassov, Vasiliy V; Weiderpass, Elisabete; Wiersma, Steven T; Younis, Mustafa; Yu, Chuanhua; Zaki, Maysaa El Sayed; Cooke, Graham S

    2016-01-01

    Summary Background With recent improvements in vaccines and treatments against viral hepatitis, an improved understanding of the burden of viral hepatitis is needed to inform global intervention strategies. We used data from the Global Burden of Disease (GBD) Study to estimate morbidity and mortality for acute viral hepatitis, and for cirrhosis and liver cancer caused by viral hepatitis, by age, sex, and country from 1990 to 2013. Methods We estimated mortality using natural history models for acute hepatitis infections and GBD’s cause-of-death ensemble model for cirrhosis and liver cancer. We used meta-regression to estimate total cirrhosis and total liver cancer prevalence, as well as the proportion of cirrhosis and liver cancer attributable to each cause. We then estimated cause-specific prevalence as the product of the total prevalence and the proportion attributable to a specific cause. Disability-adjusted life-years (DALYs) were calculated as the sum of years of life lost (YLLs) and years lived with disability (YLDs). Findings Between 1990 and 2013, global viral hepatitis deaths increased from 0·89 million (95% uncertainty interval [UI] 0·86–0·94) to 1·45 million (1·38–1·54); YLLs from 31·0 million (29·6–32·6) to 41·6 million (39·1–44·7); YLDs from 0·65 million (0·45–0·89) to 0·87 million (0·61–1·18); and DALYs from 31·7 million (30·2–33·3) to 42·5 million (39·9–45·6). In 2013, viral hepatitis was the seventh (95% UI seventh to eighth) leading cause of death worldwide, compared with tenth (tenth to 12th) in 1990. Interpretation Viral hepatitis is a leading cause of death and disability worldwide. Unlike most communicable diseases, the absolute burden and relative rank of viral hepatitis increased between 1990 and 2013. The enormous health loss attributable to viral hepatitis, and the availability of effective vaccines and treatments, suggests an important opportunity to improve public health. Funding Bill & Melinda

  19. Biomass burning studies and the International Global Atmospheric Chemistry (IGAC) project

    Science.gov (United States)

    Prinn, Ronald G.

    1991-01-01

    IGAC is an ambitious, decade-long and global research initiative concerned with major research challenges in the field of atmospheric chemistry; its chemists and ecosystem biologists are addressing the problems associated with global biomass burning (BMB). Among IGAC's goals is the achievement of a fundamental understanding of the natural and anthropogenic processes determining changes in atmospheric composition and chemistry, in order to allow century-long predictions. IGAC's studies have been organized into 'foci', encompassing the marine, tropical, polar, boreal, and midlatitude areas, as well as their global composite interactions. Attention is to be given to the effects of BMB on biogeochemical cycles.

  20. A global benchmark study using affinity-based biosensors

    DEFF Research Database (Denmark)

    Rich, Rebecca L; Papalia, Giuseppe A; Flynn, Peter J

    2009-01-01

    To explore the variability in biosensor studies, 150 participants from 20 countries were given the same protein samples and asked to determine kinetic rate constants for the interaction. We chose a protein system that was amenable to analysis using different biosensor platforms as well as by users...... the remaining panel of participants was 620 pM with a standard deviation of 980 pM. These results demonstrate that when this biosensor assay was designed and executed appropriately, the reported rate constants were consistent, and independent of which protein was immobilized and which biosensor was used....

  1. Global Burden Of Disease Studies: Implications For Mental And Substance Use Disorders.

    Science.gov (United States)

    Whiteford, Harvey; Ferrari, Alize; Degenhardt, Louisa

    2016-06-01

    Global Burden of Disease studies have highlighted mental and substance use disorders as the leading cause of disability globally. Using the studies' findings for policy and planning requires an understanding of how estimates are generated, the required epidemiological data are gathered, disability and premature mortality are defined and counted, and comparative risk assessment for risk-factor analysis is undertaken. The high burden of mental and substance use disorders has increased their priority on the global health agenda, but not enough to prompt concerted action by governments and international agencies. Using Global Burden of Disease estimates in health policy and planning requires combining them with other information such as evidence on the cost-effectiveness of interventions designed to reduce the disorders' burden. Concerted action is required by mental health advocates and policy makers to assemble this evidence, taking into account the health, social, and economic challenges facing each country. Project HOPE—The People-to-People Health Foundation, Inc.

  2. Sensitivity study of heavy precipitation in Limited Area Model climate simulations: influence of the size of the domain and the use of the spectral nudging technique

    Science.gov (United States)

    Colin, Jeanne; Déqué, Michel; Radu, Raluca; Somot, Samuel

    2010-10-01

    We assess the impact of two sources of uncertainties in a limited area model (LAM) on the representation of intense precipitation: the size of the domain of integration and the use of the spectral nudging technique (driving of the large-scale within the domain of integration). We work in a perfect-model approach where the LAM is driven by a general circulation model (GCM) run at the same resolution and sharing the same physics and dynamics as the LAM. A set of three 50 km resolution simulations run over Western Europe with the LAM ALADIN-Climate and the GCM ARPEGE-Climate are performed to address this issue. Results are consistent with previous studies regarding the seasonal-mean fields. Furthermore, they show that neither the use of the spectral nudging nor the choice of a small domain are detrimental to the modelling of heavy precipitation in the present experiment.

  3. Effects of global and local contexts on chord processing: An ERP study.

    Science.gov (United States)

    Zhang, Jingjing; Zhou, Xuefeng; Chang, Ruohan; Yang, Yufang

    2018-01-31

    In real life, the processing of an incoming event is continuously influenced by prior information at multiple timescales. The present study investigated how harmonic contexts at both local and global levels influence the processing of an incoming chord in an event-related potentials experiment. Chord sequences containing two phrases were presented to musically trained listeners, with the last critical chord either harmonically related or less related to its preceding context at local and/or global levels. ERPs data showed an ERAN-like effect for local context in early time window and a N5-like component for later interaction between the local context and global context. These results suggest that both the local and global contexts influence the processing of an incoming music event, and the local effect happens earlier than the global. Moreover, the interaction between the local context and global context in N5 may suggest that music syntactic integration at local level takes place prior to the integration at global level. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Global Obesity Study on Drivers for Weight Reduction Strategies

    Directory of Open Access Journals (Sweden)

    Carola Grebitus

    2015-01-01

    Full Text Available Objective: To assess factors determining the reaction of individuals to the threats of overweight and obesity and to examine the interdependencies between weight-reducing strategies. Methods: Cross-country survey covering 19 countries and 13,155 interviews. Data were analysed using a bivariate probit model that allows simultaneously analysing two weight-reducing strategies. Results: Results show that weight-reducing strategies chosen are not independent from each other. Findings also reveal that different strategies are chosen by different population segments. Women are more likely to change their dietary patterns and less likely to become physically active after surpassing a weight threshold. In addition, the probability of a dietary change in case of overweight differs considerably between countries. The study also reveals that attitudes are an important factor for the strategy choice. Conclusions: It is vital for public health policies to understand determinants of citizens' engagement in weight reduction strategies once a certain threshold is reached. Thus, results can support the design of public health campaigns and programmes that aim to change community or national health behaviour trends taking into account, e.g., national differences.

  5. Multivariate spectral-analysis of movement-related EEG data

    International Nuclear Information System (INIS)

    Andrew, C. M.

    1997-01-01

    The univariate method of event-related desynchronization (ERD) analysis, which quantifies the temporal evolution of power within specific frequency bands from electroencephalographic (EEG) data recorded during a task or event, is extended to an event related multivariate spectral analysis method. With this method, time courses of cross-spectra, phase spectra, coherence spectra, band-averaged coherence values (event-related coherence, ERCoh), partial power spectra and partial coherence spectra are estimated from an ensemble of multivariate event-related EEG trials. This provides a means of investigating relationships between EEG signals recorded over different scalp areas during the performance of a task or the occurrence of an event. The multivariate spectral analysis method is applied to EEG data recorded during three different movement-related studies involving discrete right index finger movements. The first study investigates the impact of the EEG derivation type on the temporal evolution of interhemispheric coherence between activity recorded at electrodes overlying the left and right sensorimotor hand areas during cued finger movement. The question results whether changes in coherence necessarily reflect changes in functional coupling of the cortical structures underlying the recording electrodes. The method is applied to data recorded during voluntary finger movement and a hypothesis, based on an existing global/local model of neocortical dynamics, is formulated to explain the coherence results. The third study applies partial spectral analysis too, and investigates phase relationships of, movement-related data recorded from a full head montage, thereby providing further results strengthening the global/local hypothesis. (author)

  6. UNESCO Global Geoparks, Geotourism and Communication of the Earth Sciences: A Case Study in the Chablais UNESCO Global Geopark, France

    Directory of Open Access Journals (Sweden)

    Sophie Catherine Justice

    2018-04-01

    Full Text Available The last twenty years have seen considerable developments in geotourism, a form of sustainable tourism. This has been also a period of significant development for UNESCO Global Geoparks (UGGps, on one hand with the creation of the International Geoscience and Geoparks Programme, and the other, in the number and diversity of UGGps recognised across the world. Geoparks have particular characteristics, such as a spatial engagement across an area, as well as the long-term commitment associated with this type of label. UGGps take a broad approach to geotourism, and seek to engage with all demographics, including “unsuspecting” geotourists. This is particularly relevant when considering that the Geopark profile has evolved since the introduction of the UNESCO label, and that a number UGGps are pre-existing tourist destinations and have diverse economies and strong growth. UGGps draw on professional, multidisciplinary teams that combine scientific knowledge, science communication, and outreach events to achieve effective heritage transmission through actions that target schools, the local population, and the general public. These are not traditional structures and do not have behavioural constraints imposed on them as experienced by some educational structures or museums. The present case study is an example of the type of innovation seen in UGGps, whereby novel solutions are employed in order to touch as wide a public as possible. The action presented is a winter outreach event for the general public in the Chablais UNESCO Global Geopark (France, that was developed in partnership with the Portes du Soleil association of 12 ski resorts. This consisted of an orienteering/treasure hunt game across one of the world’s largest ski domains, that included panels with anecdotes presenting different aspects of the Chablais geoheritage. It demonstrates that it is possible to engage with a sporting public that is seeking experiences and is not expecting to

  7. Experimental study of the use of multiband acousto-optic filters for spectral encoding / decoding the optical signals

    International Nuclear Information System (INIS)

    Proklov, V V; Byshevski-Konopko, O A; Filatov, A L; Lugovskoi, A V; Pisarevsky, Yu V

    2016-01-01

    A prototype of the acousto-optic (AO) decoder of optical signals is created on the base of the multiband AO filter. The joint work of the decoder with the developed previously AO coder has been verified experimentally. The main qualitative and quantitate characteristics of the spectral coding and decoding by Walsh sequences of the industrial LED radiation in the near infrared range are investigated. It is shown, that in the proposed data transmission system realization Signal-to-Interference Ratio (SIR) is not less than 13 dB. (paper)

  8. Non-opioid analgesic drug flupirtine: Spectral analysis, DFT computations, in vitro bioactivity and molecular docking study

    Science.gov (United States)

    Leenaraj, D. R.; Hubert Joe, I.

    2017-06-01

    Spectral features of non-opioid analgesic drug flupirtine have been explored by the Fourier transform infrared, Raman and Nuclear magnetic resonance spectroscopic techniques combined with density functional theory computations. The bioactive conformer of flupirtine is stabilized by an intramolecular Csbnd H⋯N hydrogen bonding resulting by the steric strain of hydrogen atoms. Natural bond orbital and natural population analysis support this result. The charge redistribution also has been analyzed. Antimicrobial activities of flupirtine have been screened by agar well disc diffusion and molecular docking methods, which exposes the importance of triaminopyridine in flupirtine.

  9. Assessment of damage in composite laminates through dynamic, full-spectral interrogation of fiber Bragg grating sensors

    International Nuclear Information System (INIS)

    Propst, A; Peters, K; Zikry, M A; Schultz, S; Kunzler, W; Zhu, Z; Wirthlin, M; Selfridge, R

    2010-01-01

    In this study, we demonstrate the full-spectral interrogation of a fiber Bragg grating (FBG) sensor at 535 Hz. The sensor is embedded in a woven, graphite fiber–epoxy composite laminate subjected to multiple low-velocity impacts. The measurement of unique, time dependent spectral features from the FBG sensor permits classification of the laminate lifetime into five regimes. These damage regimes compare well with previous analysis of the same material system using combined global and local FBG sensor information. Observed transient spectral features include peak splitting, wide spectral broadening and a strong single peak at the end of the impact event. Such features could not be measured through peak wavelength interrogation of the FBG sensor. Cross-correlation of the measured spectra with the original embedded FBG spectrum permitted rapid visualization of average strains and the presence of transverse compressive strain on the optical fiber, but smeared out the details of the spectral profile

  10. Spectral evolution of GRBs with negative spectral lag using Fermi GBM observations

    Science.gov (United States)

    Chakrabarti, Arundhati; Chaudhury, Kishor; Sarkar, Samir K.; Bhadra, Arunava

    2018-06-01

    The positive spectral lag of Gamma Ray Bursts (GRBs) is often explained in terms of hard-to-soft spectral evolution of GRB pulses. While positive lags of GRBs is very common, there are few GRB pulses that exhibits negative spectral lags. In the present work we examine whether negative lags of GRBs also can be interpreted in terms of spectral evolution of GRB pulses or not. Using Fermi-GBM data, we identify two GRBs, GRB 090426C and GRB 150213A, with clean pulses that exhibit negative spectral lag. An indication of soft to hard transition has been noticed for the negative spectral lag events from the spectral evolution study. The implication of the present findings on the models of GRB spectral lags are discussed.

  11. A Collection of Studies Conducted in Education about "Global Warming" Problem

    Science.gov (United States)

    Bozdogan, Aykut Emre

    2011-01-01

    The studies global warming problem conducted in education discipline in the world and in Turkey were analysed for this study. The literature was reviewed extensively especially through the articles in the indexed journals of Ebsco Host, Science Direct, Taylor and Francis and Web of Science databases and this study was conducted according to the…

  12. A study on spectral energy for the end of the twentieth century the basis of the NCEP reanalysis-II

    Science.gov (United States)

    Aranha, A. F.; Veiga, J. A.; Yoshida, M. C.

    2013-05-01

    The energy cycle proposed by Lorenz (1955) is composed of the behavior of the average energy from the atmosphere and characteristics of atmospheric energy deviations from this average, respectively called basic state and perturbed state. However, it is possible to discretize the energy contained in the atmosphere disturbed state, decomposing the fields of the various disturbances or harmonics wave type, so as to measure and analyze the energy of these disorders according to their number or wavelength, this methodology described second Saltzman (1957). Therefore, in view of the spectral analysis as a methodological basis, this work aims to study the energy contained by the atmosphere in disturbed state. Considering the terms of power generation potential available for nth waves due to diabatic heating, represented by (G(n)), potential energy of nth wave (P(n)) and kinetic energy of nth wave (K(n)) and the conversion of energy between the energy nth kinetic and potential energy of waves nth waves given by (C(n)). The variables used in the calculation of the terms above are, temperature (T) orthogonal components of the wind (u, v, w) and geopotential height (G) from a data set from the National Center for Environmental Prediction (NCEP) considering daily shared values on a regular grid with a spatial resolution of 2.5° × 2.5°, distributed in 12 pressure levels (1000, 925, 850, 700, 600, 500, 400, 300, 250, 200, 150, 100 hPa ) for the 1970 to 1999 period. The results show that for kinetic energy of disturbance to nth wave, the amount of energy is somewhat dammed during for the first 10 wave numbers in this range are the planetary waves and waves. Observing this way, we can conclude that these waves are responsible for much of the kinetic energy in disturbed state. A characteristic and a difference in the distribution of energy between kinetic energy and potential energy disturbed total available to disturbance, is the derivative of the energy wavenumber presented by

  13. Synthesis of metal complexes involving Schiff base ligand with methylenedioxy moiety: spectral, thermal, XRD and antimicrobial studies.

    Science.gov (United States)

    Sundararajan, M L; Jeyakumar, T; Anandakumaran, J; Karpanai Selvan, B

    2014-10-15

    Metal complexes of Zn(II), Cd(II), Ni(II), Cu(II), Fe(III), Co(II), Mn(II) Hg(II), and Ag(I) have been synthesized from Schiff base ligand, prepared by the condensation of 3,4-(methylenedioxy)aniline and 5-bromo salicylaldehyde. All the compounds have been characterized by using elemental analysis, molar conductance, FT-IR, UV-Vis, (1)H NMR, (13)C NMR, mass spectra, powder XRD and thermal analysis (TG/DTA) technique. The elemental analysis suggests the stoichiometry to be 1:1 (metal:ligand). The FT-IR, (1)H NMR, (13)C NMR and UV-Vis spectral data suggest that the ligand coordinate to the metal atom by imino nitrogen and phenolic oxygen as bidentate manner. Mass spectral data further support the molecular mass of the compounds and their structure. Powder XRD indicates the crystalline state and morphology of the ligand and its metal complexes. The thermal behaviors of the complexes prove the presence of lattice as well as coordinated water molecules in the complexes. Melting point supports the thermal stability of all the compounds. The in vitro antimicrobial effects of the synthesized compounds were tested against five bacterial and three fungal species by well diffusion method. Antioxidant activities have also been performed for all the compounds. Metal complexes show more biological activity than the Schiff base. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Influence of intermolecular amide hydrogen bonding on the geometry, atomic charges, and spectral modes of acetanilide: An ab initio study

    Science.gov (United States)

    Binoy, J.; Prathima, N. B.; Murali Krishna, C.; Santhosh, C.; Hubert Joe, I.; Jayakumar, V. S.

    2006-08-01

    Acetanilide, a compound of pharmaceutical importance possessing pain-relieving properties due to its blocking the pulse dissipating along the nerve fiber, is subjected to vibrational spectral investigation using NIR FT Raman, FT-IR, and SERS. The geometry, Mulliken charges, and vibrational spectrum of acetanilide have been computed using the Hartree-Fock theory and density functional theory employing the 6-31G (d) basis set. To investigate the influence of intermolecular amide hydrogen bonding, the geometry, charge distribution, and vibrational spectrum of the acetanilide dimer have been computed at the HF/6-31G (d) level. The computed geometries reveal that the acetanilide molecule is planar, while twisting of the secondary amide group with respect to the phenyl ring is found upon hydrogen bonding. The trans isomerism and “amido” form of the secondary amide, hyperconjugation of the C=O group with the adjacent C-C bond, and donor-acceptor interaction have been investigated using computed geometry. The carbonyl stretching band position is found to be influenced by the tendency of the phenyl ring to withdraw nitrogen lone pair, intermolecular hydrogen bonding, conjugation, and hyperconjugation. A decrease in the NH and C=O bond orders and increase in the C-N bond orders due to donor-acceptor interaction can be observed in the vibrational spectra. The SERS spectral analysis reveals that the flat orientation of the molecule on the adsorption plane is preferred.

  15. Evans hole and non linear optical activity in Bis(melaminium) sulphate dihydrate: A vibrational spectral study.

    Science.gov (United States)

    Suresh Kumar, V R; Binoy, J; Dawn Dharma Roy, S; Marchewka, M K; Jayakumar, V S

    2015-01-01

    Bis(melaminium) sulphate dihydrate (BMSD), an interesting melaminium derivative for nonlinear optical activity, has been subjected to vibrational spectral analysis using FT IR and FT Raman spectra. The analysis has been aided by the Potential Energy Distribution (PED) of vibrational spectral bands, derived using density functional theory (DFT) at B3LYP/6-31G(d) level. The geometry is found to correlate well with the XRD structure and the band profiles for certain vibrations in the finger print region have been theoretically explained using Evans hole. The detailed Natural Bond Orbital (NBO) analysis of the hydrogen bonding in BMSD has also been carried out to understand the correlation between the stabilization energy of hyperconjugation of the lone pair of donor with the σ(∗) orbital of hydrogen-acceptor bond and the strength of hydrogen bond. The theoretical calculation shows that BMSD has NLO efficiency, 2.66 times that of urea. The frontier molecular orbital analysis points to a charge transfer, which contributes to NLO activity, through N-H…O intermolecular hydrogen bonding between the melaminium ring and the sulphate. The molecular electrostatic potential (MEP) mapping has also been performed for the detailed analysis of the mutual interactions between melaminium ring and sulphate ion. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Information data systems for a global change technology initiative architecture trade study

    Science.gov (United States)

    Murray, Nicholas D.

    1991-01-01

    The Global Change Technology Initiative (GCTI) was established to develop technology which will enable use of satellite systems of Earth observations on a global scale, enable use of the observations to predictively model Earth's changes, and provide scientists, government, business, and industry with quick access to the resulting information. At LaRC, a GCTI Architecture Trade Study was undertaken to develop and evaluate the architectural implications to meet the requirements of the global change studies and the eventual implementation of a global change system. The output of the trade study are recommended technologies for the GCTI. That portion of the study concerned with the information data system is documented. The information data system for an earth global change modeling system can be very extensive and beyond affordability in terms of today's costs. Therefore, an incremental approach to gaining a system is most likely. An options approach to levels of capability versus needed technologies was developed. The primary drivers of the requirements for the information data system evaluation were the needed science products, the science measurements, the spacecraft orbits, the instruments configurations, and the spacecraft configurations and their attendant architectures. The science products requirements were not studied here; however, some consideration of the product needs were included in the evaluation results. The information data system technology items were identified from the viewpoint of the desirable overall information system characteristics.

  17. The Study on Global Oil and Gas Supply and Demand undertaken by the National Petroleum Council

    Energy Technology Data Exchange (ETDEWEB)

    Slutz, James

    2007-07-01

    The National Petroleum Council (NPC) Study on Global Oil and Gas is one of the most comprehensive studies on global oil and gas supply and demand projections ever undertaken to date. This study comprises approximately 250 experts from industry, government, research institutions, academia, energy ministries from around the world, national oil companies, and non-government organizations. The NPC study team has collected and analyzed global data on supply and demand trends through the year 2030. While other studies have examined the economic, environmental, security and geo-policy implications of the oil and gas supply and demand picture, this study examines all three political priorities simultaneously. The multi-dimensional foundations of the policy recommendations, and the diverse expertise of study group members, results in findings which are truly unique, and separate this study from numerous previous studies on global oil and gas supply and demand. Although key findings and policy recommendations will not be released prior to the study's release in June of 2007, the following paper provides the scope of work and the detailed project plan that will result in an energy outlook that is differentiated from all recent studies.

  18. Creating and Implementing an Offshore Graduate Program: A Case Study of Leadership and Development of the Global Executive MBA Program

    Science.gov (United States)

    Herrera, Marisa L.

    2013-01-01

    This study applies the literature on leadership framing to the globalization of higher education to understand the development of the Global Executive MBA program at a large university. The purpose of the study was to provide administrators, educators and university leaders an understanding as to how to respond to globalization and, secondly, to…

  19. Spectral analysis and quantum chemical studies of chair and twist-boat conformers of cycloheximide in gas and solution phases

    Science.gov (United States)

    Tokatli, A.; Ucun, F.; Sütçü, K.; Osmanoğlu, Y. E.; Osmanoğlu, Ş.

    2018-02-01

    In this study the conformational behavior of cycloheximide in the gas and solution (CHCl3) phases has theoretically been investigated by spectroscopic and quantum chemical properties using density functional theory (wB97X-D) method with 6-31++G(d,p) basis set, for the first time. The calculated IR results reveal that in the ground state the molecule exits as a mixture of the chair and twist-boat conformers in the gas phase, while the calculated NMR results reveal that it only exits as the chair conformer in the solution phase. In order to obtain the contributions coming from intramolecular interactions to the stability of the conformers in the gas and solution phases, the quantum theory of atoms in molecules (QTAIM), noncovalent interactions (NCI) method, and natural bond orbital analysis (NBO) have been employed. The QTAIM and NCI methods indicated that by intramolecular interactions with bond critical point (BCP) the twist-boat conformer is more stabilized than the chair conformer, while by steric interactions it is more destabilized. Considering that these interactions balance each other, the stabilities of the conformers are understood to be dictated by the van der Waals interactions. The NBO analyses show that the hyperconjugative and steric effects play an important role in the stabilization in the gas and solution phases. Furthermore, to get a better understanding of the chemical behavior of this important antibiotic drug we have evaluated and, commented the global and local reactivity descriptors of the both conformers. Finally, the EPR analysis of γ-irradiated cycloheximide has been done. The comparison of the experimental and calculated data have showed the inducement of a radical structure of (CH2)2ĊCH2 in the molecule. The experimental EPR spectrum has also confirmed that the molecule simultaneously exists in the chair and twist-boat conformers in the solid phase.

  20. Spectral filtering for plant production

    Energy Technology Data Exchange (ETDEWEB)

    Young, R.E.; McMahon, M.J.; Rajapakse, N.C.; Becoteau, D.R.

    1994-12-31

    Research to date suggests that spectral filtering can be an effective alternative to chemical growth regulators for altering plant development. If properly implemented, it can be nonchemical and environmentally friendly. The aqueous CuSO{sub 4}, and CuCl{sub 2} solutions in channelled plastic panels have been shown to be effective filters, but they can be highly toxic if the solutions contact plants. Some studies suggest that spectral filtration limited to short EOD intervals can also alter plant development. Future research should be directed toward confirmation of the influence of spectral filters and exposure times on a broader range of plant species and cultivars. Efforts should also be made to identify non-noxious alternatives to aqueous copper solutions and/or to incorporate these chemicals permanently into plastic films and panels that can be used in greenhouse construction. It would also be informative to study the impacts of spectral filters on insect and microbal populations in plant growth facilities. The economic impacts of spectral filtering techniques should be assessed for each delivery methodology.

  1. Adaptive Spectral Doppler Estimation

    DEFF Research Database (Denmark)

    Gran, Fredrik; Jakobsson, Andreas; Jensen, Jørgen Arendt

    2009-01-01

    . The methods can also provide better quality of the estimated power spectral density (PSD) of the blood signal. Adaptive spectral estimation techniques are known to pro- vide good spectral resolution and contrast even when the ob- servation window is very short. The 2 adaptive techniques are tested......In this paper, 2 adaptive spectral estimation techniques are analyzed for spectral Doppler ultrasound. The purpose is to minimize the observation window needed to estimate the spectrogram to provide a better temporal resolution and gain more flexibility when designing the data acquisition sequence...... and compared with the averaged periodogram (Welch’s method). The blood power spectral capon (BPC) method is based on a standard minimum variance technique adapted to account for both averaging over slow-time and depth. The blood amplitude and phase estimation technique (BAPES) is based on finding a set...

  2. The influence of spectral nudging on typhoon formation in regional climate models

    Science.gov (United States)

    Feser, Frauke; Barcikowska, Monika

    2012-03-01

    Regional climate models can successfully simulate tropical cyclones and typhoons. This has been shown and was evaluated for hindcast studies of the past few decades. But often global and regional weather phenomena are not simulated at the observed location, or occur too often or seldom even though the regional model is driven by global reanalysis data which constitute a near-realistic state of the global atmosphere. Therefore, several techniques have been developed in order to make the regional model follow the global state more closely. One is spectral nudging, which is applied for horizontal wind components with increasing strength for higher model levels in this study. The aim of this study is to show the influence that this method has on the formation of tropical cyclones (TC) in regional climate models. Two ensemble simulations (each with five simulations) were computed for Southeast Asia and the Northwestern Pacific for the typhoon season 2004, one with spectral nudging and one without. First of all, spectral nudging reduced the overall TC number by about a factor of 2. But the number of tracks which are similar to observed best track data (BTD) was greatly increased. Also, spatial track density patterns were found to be more similar when using spectral nudging. The tracks merge after a short time for the spectral nudging simulations and then follow the BTD closely; for the no nudge cases the similarity is greatly reduced. A comparison of seasonal precipitation, geopotential height, and temperature fields at several height levels with observations and reanalysis data showed overall a smaller ensemble spread, higher pattern correlations and reduced root mean square errors and biases for the spectral nudged simulations. Vertical temperature profiles for selected TCs indicate that spectral nudging is not inhibiting TC development at higher levels. Both the Madden-Julian Oscillation and monsoonal precipitation are reproduced realistically by the regional model

  3. The influence of spectral nudging on typhoon formation in regional climate models

    International Nuclear Information System (INIS)

    Feser, Frauke; Barcikowska, Monika

    2012-01-01

    Regional climate models can successfully simulate tropical cyclones and typhoons. This has been shown and was evaluated for hindcast studies of the past few decades. But often global and regional weather phenomena are not simulated at the observed location, or occur too often or seldom even though the regional model is driven by global reanalysis data which constitute a near-realistic state of the global atmosphere. Therefore, several techniques have been developed in order to make the regional model follow the global state more closely. One is spectral nudging, which is applied for horizontal wind components with increasing strength for higher model levels in this study. The aim of this study is to show the influence that this method has on the formation of tropical cyclones (TC) in regional climate models. Two ensemble simulations (each with five simulations) were computed for Southeast Asia and the Northwestern Pacific for the typhoon season 2004, one with spectral nudging and one without. First of all, spectral nudging reduced the overall TC number by about a factor of 2. But the number of tracks which are similar to observed best track data (BTD) was greatly increased. Also, spatial track density patterns were found to be more similar when using spectral nudging. The tracks merge after a short time for the spectral nudging simulations and then follow the BTD closely; for the no nudge cases the similarity is greatly reduced. A comparison of seasonal precipitation, geopotential height, and temperature fields at several height levels with observations and reanalysis data showed overall a smaller ensemble spread, higher pattern correlations and reduced root mean square errors and biases for the spectral nudged simulations. Vertical temperature profiles for selected TCs indicate that spectral nudging is not inhibiting TC development at higher levels. Both the Madden–Julian Oscillation and monsoonal precipitation are reproduced realistically by the regional model

  4. Study of global control of VIRGO Central Interferometer; Etude du controle global de l'Interferometre Central de VIRGO

    Energy Technology Data Exchange (ETDEWEB)

    Matone, Luca [Paris-11 Univ., 91 Orsay (France)

    1999-10-29

    The VIRGO project for the detection of gravitational waves will first operate in a test configuration, known as the Central Area Interferometer (CITF). The subject of this thesis consists of a study for the global control of this interferometer. In particular, the problems of auto-alignment and acquisition of lock are addressed. First, an investigation of the CITF optical response to longitudinal and angular mirror movements is given. On the basis of this study, we show how the ratio of photodiode signals can be used to detect and control the dark fringe when the CITF is far from its operating point (locked state). Furthermore, we present the simulation results of a quadrant photodiode configuration capable of reconstructing the mirrors' tilts once the CITF is in a locked state. The performance of a control system for the auto-alignment is then given. A study on the mode-cleaner prototype MC30 is then introduced in order to comprehend the process of lock acquisition by a linear feedback system for two different finesse values: F {approx_equal}100 and F {approx_equal} 1600. We define a threshold velocity for the mirrors' relative motion below which acquisition of lock is possible. A phenomenon, referred to as ringing effect, was observed and examined on the MC30 prototype in high finesse. The results of numerical calculations allowed us to fit measurement and estimate from them the cavity finesse as well as the mirrors' relative velocity during the resonance crossing. An empirical formula is then presented capable of determine the relative velocity from the positions of the oscillations' minima and maxima. An algorithm to guide into lock the CITF is then presented, consisting of an iterative procedure of velocity reconstruction and pulse application. A numerical calculation simulated the algorithm, the mirrors' motion, the optical response and the ADCs' process. As a result, acquisition times of the order of one second were observed: an improvement of more than one

  5. In-cloud oxalate formation in the global troposphere: a 3-D modeling study

    Directory of Open Access Journals (Sweden)

    S. Myriokefalitakis

    2011-06-01

    Full Text Available Organic acids attract increasing attention as contributors to atmospheric acidity, secondary organic aerosol mass and aerosol hygroscopicity. Oxalic acid is globally the most abundant dicarboxylic acid, formed via chemical oxidation of gas-phase precursors in the aqueous phase of aerosols and droplets. Its lifecycle and atmospheric global distribution remain highly uncertain and are the focus of this study. The first global spatial and temporal distribution of oxalate, simulated using a state-of-the-art aqueous-phase chemical scheme embedded within the global 3-dimensional chemistry/transport model TM4-ECPL, is here presented. The model accounts for comprehensive gas-phase chemistry and its coupling with major aerosol constituents (including secondary organic aerosol. Model results are consistent with ambient observations of oxalate at rural and remote locations (slope = 1.16 ± 0.14, r2 = 0.36, N = 114 and suggest that aqueous-phase chemistry contributes significantly to the global atmospheric burden of secondary organic aerosol. In TM4-ECPL most oxalate is formed in-cloud and less than 5 % is produced in aerosol water. About 62 % of the oxalate is removed via wet deposition, 30 % by in-cloud reaction with hydroxyl radical, 4 % by in-cloud reaction with nitrate radical and 4 % by dry deposition. The in-cloud global oxalate net chemical production is calculated to be about 21–37 Tg yr−1 with almost 79 % originating from biogenic hydrocarbons, mainly isoprene. This condensed phase net source of oxalate in conjunction with a global mean turnover time against deposition of about 5 days, maintain oxalate's global tropospheric burden of 0.2–0.3 Tg, i.e. 0.05–0.1 Tg-C that is about 5–9 % of model-calculated water soluble organic carbon burden.

  6. A stable pattern of EEG spectral coherence distinguishes children with autism from neuro-typical controls - a large case control study.

    Science.gov (United States)

    Duffy, Frank H; Als, Heidelise

    2012-06-26

    The autism rate has recently increased to 1 in 100 children. Genetic studies demonstrate poorly understood complexity. Environmental factors apparently also play a role. Magnetic resonance imaging (MRI) studies demonstrate increased brain sizes and altered connectivity. Electroencephalogram (EEG) coherence studies confirm connectivity changes. However, genetic-, MRI- and/or EEG-based diagnostic tests are not yet available. The varied study results likely reflect methodological and population differences, small samples and, for EEG, lack of attention to group-specific artifact. Of the 1,304 subjects who participated in this study, with ages ranging from 1 to 18 years old and assessed with comparable EEG studies, 463 children were diagnosed with autism spectrum disorder (ASD); 571 children were neuro-typical controls (C). After artifact management, principal components analysis (PCA) identified EEG spectral coherence factors with corresponding loading patterns. The 2- to 12-year-old subsample consisted of 430 ASD- and 554 C-group subjects (n = 984). Discriminant function analysis (DFA) determined the spectral coherence factors' discrimination success for the two groups. Loading patterns on the DFA-selected coherence factors described ASD-specific coherence differences when compared to controls. Total sample PCA of coherence data identified 40 factors which explained 50.8% of the total population variance. For the 2- to 12-year-olds, the 40 factors showed highly significant group differences (P EEG coherence-based phenotype of childhood autism. The predominantly reduced short-distance coherences may indicate poor local network function. The increased long-distance coherences may represent compensatory processes or reduced neural pruning. The wide average spectral range of factor loadings may suggest over-damped neural networks.

  7. A stable pattern of EEG spectral coherence distinguishes children with autism from neuro-typical controls - a large case control study

    Directory of Open Access Journals (Sweden)

    Duffy Frank H

    2012-06-01

    Full Text Available Abstract Background The autism rate has recently increased to 1 in 100 children. Genetic studies demonstrate poorly understood complexity. Environmental factors apparently also play a role. Magnetic resonance imaging (MRI studies demonstrate increased brain sizes and altered connectivity. Electroencephalogram (EEG coherence studies confirm connectivity changes. However, genetic-, MRI- and/or EEG-based diagnostic tests are not yet available. The varied study results likely reflect methodological and population differences, small samples and, for EEG, lack of attention to group-specific artifact. Methods Of the 1,304 subjects who participated in this study, with ages ranging from 1 to 18 years old and assessed with comparable EEG studies, 463 children were diagnosed with autism spectrum disorder (ASD; 571 children were neuro-typical controls (C. After artifact management, principal components analysis (PCA identified EEG spectral coherence factors with corresponding loading patterns. The 2- to 12-year-old subsample consisted of 430 ASD- and 554 C-group subjects (n = 984. Discriminant function analysis (DFA determined the spectral coherence factors' discrimination success for the two groups. Loading patterns on the DFA-selected coherence factors described ASD-specific coherence differences when compared to controls. Results Total sample PCA of coherence data identified 40 factors which explained 50.8% of the total population variance. For the 2- to 12-year-olds, the 40 factors showed highly significant group differences (P Conclusions Classification success suggests a stable coherence loading pattern that differentiates ASD- from C-group subjects. This might constitute an EEG coherence-based phenotype of childhood autism. The predominantly reduced short-distance coherences may indicate poor local network function. The increased long-distance coherences may represent compensatory processes or reduced neural pruning. The wide average spectral range

  8. Ion spectral structures observed by the Van Allen Probes

    Science.gov (United States)

    Ferradas, C.; Zhang, J.; Spence, H. E.; Kistler, L. M.; Larsen, B.; Reeves, G. D.; Skoug, R. M.; Funsten, H. O.

    2015-12-01

    During the last decades several missions have recorded the presence of dynamic spectral features of energetic ions in the inner magnetosphere. Previous studies have reported single "nose-like" structures occurring alone and simultaneous nose-like structures (up to three). These ion structures are named after the characteristic shapes of energy bands or gaps in the energy-time spectrograms of in situ measured ion fluxes. They constitute the observational signatures of ion acceleration, transport, and loss in the global magnetosphere. The HOPE mass spectrometer onboard the Van Allen Probes measures energetic hydrogen, helium, and oxygen ions near the inner edge of the plasma sheet, where these ion structures are observed. We present a statistical study of nose-like structures, using 2-years measurements from the HOPE instrument. The results provide important details about the spatial distribution (dependence on geocentric distance), spectral features of the structures (differences among species), and geomagnetic conditions under which these structures occur.

  9. Introduction to spectral theory

    CERN Document Server

    Levitan, B M

    1975-01-01

    This monograph is devoted to the spectral theory of the Sturm- Liouville operator and to the spectral theory of the Dirac system. In addition, some results are given for nth order ordinary differential operators. Those parts of this book which concern nth order operators can serve as simply an introduction to this domain, which at the present time has already had time to become very broad. For the convenience of the reader who is not familar with abstract spectral theory, the authors have inserted a chapter (Chapter 13) in which they discuss this theory, concisely and in the main without proofs, and indicate various connections with the spectral theory of differential operators.

  10. ALEPH Tau Spectral Functions and QCD

    CERN Document Server

    Davier, M; Zhang, Z; Davier, Michel; Hoecker, Andreas; Zhang, Zhiqing

    2007-01-01

    Hadronic $\\tau$ decays provide a clean laboratory for the precise study of quantum chromodynamics (QCD). Observables based on the spectral functions of hadronic $\\tau$ decays can be related to QCD quark-level calculations to determine fundamental quantities like the strong coupling constant, quark and gluon condensates. Using the ALEPH spectral functions and branching ratios, complemented by some other available measurements, and a revisited analysis of the theoretical framework, the value $\\asm = 0.345 \\pm 0.004_{\\rm exp} \\pm 0.009_{\\rm th}$ is obtained. Taken together with the determination of \\asZ from the global electroweak fit, this result leads to the most accurate test of asymptotic freedom: the value of the logarithmic slope of $\\alpha_s^{-1}(s)$ is found to agree with QCD at a precision of 4%. The value of \\asZ obtained from $\\tau$ decays is $\\asZ = 0.1215 \\pm 0.0004_{\\rm exp} \\pm 0.0010_{\\rm th} \\pm 0.0005_{\\rm evol} = 0.1215 \\pm 0.0012$.

  11. Comparing airborne and satellite retrievals of cloud optical thickness and particle effective radius using a spectral radiance ratio technique: two case studies for cirrus and deep convective clouds

    Science.gov (United States)

    Krisna, Trismono C.; Wendisch, Manfred; Ehrlich, André; Jäkel, Evelyn; Werner, Frank; Weigel, Ralf; Borrmann, Stephan; Mahnke, Christoph; Pöschl, Ulrich; Andreae, Meinrat O.; Voigt, Christiane; Machado, Luiz A. T.

    2018-04-01

    Solar radiation reflected by cirrus and deep convective clouds (DCCs) was measured by the Spectral Modular Airborne Radiation Measurement System (SMART) installed on the German High Altitude and Long Range Research Aircraft (HALO) during the Mid-Latitude Cirrus (ML-CIRRUS) and the Aerosol, Cloud, Precipitation, and Radiation Interaction and Dynamic of Convective Clouds System - Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud Resolving Modelling and to the Global Precipitation Measurement (ACRIDICON-CHUVA) campaigns. On particular flights, HALO performed measurements closely collocated with overpasses of the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite. A cirrus cloud located above liquid water clouds and a DCC topped by an anvil cirrus are analyzed in this paper. Based on the nadir spectral upward radiance measured above the two clouds, the optical thickness τ and particle effective radius reff of the cirrus and DCC are retrieved using a radiance ratio technique, which considers the cloud thermodynamic phase, the vertical profile of cloud microphysical properties, the presence of multilayer clouds, and the heterogeneity of the surface albedo. For the cirrus case, the comparison of τ and reff retrieved on the basis of SMART and MODIS measurements yields a normalized mean absolute deviation of up to 1.2 % for τ and 2.1 % for reff. For the DCC case, deviations of up to 3.6 % for τ and 6.2 % for reff are obtained. The larger deviations in the DCC case are mainly attributed to the fast cloud evolution and three-dimensional (3-D) radiative effects. Measurements of spectral upward radiance at near-infrared wavelengths are employed to investigate the vertical profile of reff in the cirrus. The retrieved values of reff are compared with corresponding in situ measurements using a vertical weighting method. Compared to the MODIS observations, measurements of SMART provide more information on the

  12. Do International Studies Students Have a Broader Global Awareness than Other College Students?

    Science.gov (United States)

    De Soto, William; Tajalli, Hassan; Villarreal, Alison

    2016-01-01

    Purpose: Common knowledge seem to suggest that international studies (IS) programs are at the forefront of helping their students better understand the world beyond United States borders. The purpose of this study is to test the proposition that IS students have a greater global awareness than other college students. Method: Hanvey's (1976) five…

  13. The clinical research office of the endourological society percutaneous nephrolithotomy global study

    DEFF Research Database (Denmark)

    Desai, Mahesh; De Lisa, Antonello; Turna, Burak

    2011-01-01

    PURPOSE: The study compared characteristics and outcomes in patients with staghorn or nonstaghorn stones who were treated with percutaneous nephrolithotomy (PCNL) within the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study. PATIENTS AND METHODS: Data over a 1-year ...

  14. Risk Based Monitoring (RBM: A global study focusing on perception and merits among clinical investigational sites

    Directory of Open Access Journals (Sweden)

    Prajna P. Kumar

    2016-12-01

    Conclusion: This unique study performed across ten emerging and developed countries strongly supported the need for systematic global training, education, and implementation of RBM regulatory guidance, with an aim for better safety of subjects and improved quality of clinical trial data. Furthermore, studies with larger sample sizes are recommended to provide an evidence-based approach.

  15. Primary School Teachers' Views about Global Education in Social Studies Courses

    Science.gov (United States)

    Bozkurt, Mahmut; Yasar, Sefik

    2016-01-01

    Problem Statement: In recent years in Turkey, studies have been conducted that focus on the effects that globalisation has on education, but there have not been any papers based on the historical and conceptual framework of global education. Examining the literature, it can be argued that social studies courses have played a role in preparing…

  16. Topographic power spectral density study of the effect of surface treatment processes on niobium for superconducting radio frequency accelerator cavities

    Science.gov (United States)

    Xu, Chen; Tian, Hui; Reece, Charles E.; Kelley, Michael J.

    2012-04-01

    Microroughness is viewed as a critical issue for attaining optimum performance of superconducting radio frequency accelerator cavities. The principal surface smoothing methods are buffered chemical polish (BCP) and electropolish (EP). The resulting topography is characterized by atomic force microscopy (AFM). The power spectral density (PSD) of AFM data provides a more thorough description of the topography than a single-value roughness measurement. In this work, one dimensional average PSD functions derived from topography of BCP and EP with different controlled starting conditions and durations have been fitted with a combination of power law, K correlation, and shifted Gaussian models to extract characteristic parameters at different spatial harmonic scales. While the simplest characterizations of these data are not new, the systematic tracking of scale-specific roughness as a function of processing is new and offers feedback for tighter process prescriptions more knowledgably targeted at beneficial niobium topography for superconducting radio frequency applications.

  17. Topographic power spectral density study of the effect of surface treatment processes on niobium for superconducting radio frequency accelerator cavities

    International Nuclear Information System (INIS)

    Reece, Charles; Tian, Hui; Kelley, Michael; Xu, Chen

    2012-01-01

    Microroughness is viewed as a critical issue for attaining optimum performance of superconducting radio frequency accelerator cavities. The principal surface smoothing methods are buffered chemical polish (BCP) and electropolish (EP). The resulting topography is characterized by atomic force microscopy (AFM). The power spectral density (PSD) of AFM data provides a more thorough description of the topography than a single-value roughness measurement. In this work, one dimensional average PSD functions derived from topography of BCP and EP with different controlled starting conditions and durations have been fitted with a combination of power law, K correlation, and shifted Gaussian models to extract characteristic parameters at different spatial harmonic scales. While the simplest characterizations of these data are not new, the systematic tracking of scale-specific roughness as a function of processing is new and offers feedback for tighter process prescriptions more knowledgably targeted at beneficial niobium topography for superconducting radio frequency applications.

  18. Spectral-domain optical coherence tomography study on dynamic changes of human tears after instillation of artificial tears.

    Science.gov (United States)

    Napoli, Pietro Emanuele; Satta, Giovanni Maria; Coronella, Franco; Fossarello, Maurizio

    2014-07-01

    To analyze in vivo the dynamic changes induced by different artificial tears (ATs) in the precorneal tear film (PCTF) and lower tear meniscus (LTM) by using spectral-domain (SD) anterior segment optical coherence tomography (OCT). We prospectively examined 42 normal human eyes by using SD-OCT imaging. On the day before OCT imaging, all enrolled subjects were evaluated for abnormalities of ocular surface. All tear film images were obtained before and after instillation of three different types of ATs (mucomimetic, lipid-based, and saline) in five serial scans: immediately (within 30 seconds), at the first, fifth, 10th, and 20th minute. Subjects received a drop of 35 μL in one randomly selected eye. All examinations were conducted in the same conditions of temperature, brightness, humidity, and time of day. Changes in the morphological pattern of both LTM and PCTF were associated with the type of artificial tear instilled on the ocular surface. Similarly, the radius of curvature (rc), the height (h), and the depth (d) showed dynamic variations depending on treatment. Although by the 20th minute, both h and d returned to baseline values in all groups, a significant difference in rc (compared with baseline) was detected for mucomimetic ATs (P = 0.04) and lipid ATs (P = 0.02). Spectral-domain OCT imaging has preliminarily proved to be a noninvasive tool to evaluate, in real time, the different changes induced by ATs instillation. An important stride in understanding the clinical response to various tear substitutes can be achieved by this objective and quantitative approach. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  19. Study on the mechanism of human blood glucose concentration measuring using mid-infrared spectral analysis technology

    Science.gov (United States)

    Li, Xiang

    2016-10-01

    All forms of diabetes increase the risk of long-term complications. Blood glucose monitoring is of great importance for controlling diabetes procedure, preventing the complications and improving the patient's life quality. At present, the clinical blood glucose concentration measurement is invasive and could be replaced by noninvasive spectroscopy analytical techniques. The mid-infrared spectral region contains strong characteristic and well-defined absorption bands. Therefore, mid-infrared provides an opportunity for monitoring blood glucose invasively with only a few discrete bonds. Although the blood glucose concentration measurement using mid-infrared spectroscopy has a lot of advantages, the disadvantage is also obvious. The absorption in this infrared region is fundamental molecular group vibration. Absorption intensity is very strong, especially for biological molecules. In this paper, it figures out that the osmosis rate of glucose has a certain relationship with the blood glucose concentration. Therefore, blood glucose concentration could be measured indirectly by measuring the glucose exudate in epidermis layer. Human oral glucose tolerance tests were carried out to verify the correlation of glucose exudation in shallow layer of epidermis layer and blood glucose concentration. As it has been explained above, the mid-infrared spectral region contains well-defined absorption bands, the intensity of absorption peak around 1123 cm-1 was selected to measure the glucose and that around 1170 cm-1 was selected as reference. Ratio of absorption peak intensity was recorded for each set of measurement. The effect and importance of the cleaning the finger to be measured before spectrum measuring are discussed and also verified by experiment.

  20. Spectral dimension of quantum geometries

    International Nuclear Information System (INIS)

    Calcagni, Gianluca; Oriti, Daniele; Thürigen, Johannes

    2014-01-01

    The spectral dimension is an indicator of geometry and topology of spacetime and a tool to compare the description of quantum geometry in various approaches to quantum gravity. This is possible because it can be defined not only on smooth geometries but also on discrete (e.g., simplicial) ones. In this paper, we consider the spectral dimension of quantum states of spatial geometry defined on combinatorial complexes endowed with additional algebraic data: the kinematical quantum states of loop quantum gravity (LQG). Preliminarily, the effects of topology and discreteness of classical discrete geometries are studied in a systematic manner. We look for states reproducing the spectral dimension of a classical space in the appropriate regime. We also test the hypothesis that in LQG, as in other approaches, there is a scale dependence of the spectral dimension, which runs from the topological dimension at large scales to a smaller one at short distances. While our results do not give any strong support to this hypothesis, we can however pinpoint when the topological dimension is reproduced by LQG quantum states. Overall, by exploring the interplay of combinatorial, topological and geometrical effects, and by considering various kinds of quantum states such as coherent states and their superpositions, we find that the spectral dimension of discrete quantum geometries is more sensitive to the underlying combinatorial structures than to the details of the additional data associated with them. (paper)

  1. Buckling feedback of the spectral calculations

    International Nuclear Information System (INIS)

    Jing Xingqing; Shan Wenzhi; Luo Jingyu

    1992-01-01

    This paper studies the problems about buckling feedback of spectral calculations in physical calculations of the reactor and presents a useful method by which the buckling feedback of spectral calculations is implemented. The effect of the buckling feedback in spectra and the broad group cross section, convergence of buckling feedback iteration and the effect of the spectral zones dividing are discussed in the calculations. This method has been used for the physical design of HTR-10 MW Test Module

  2. A method to determine the necessity for global signal regression in resting-state fMRI studies.

    Science.gov (United States)

    Chen, Gang; Chen, Guangyu; Xie, Chunming; Ward, B Douglas; Li, Wenjun; Antuono, Piero; Li, Shi-Jiang

    2012-12-01

    In resting-state functional MRI studies, the global signal (operationally defined as the global average of resting-state functional MRI time courses) is often considered a nuisance effect and commonly removed in preprocessing. This global signal regression method can introduce artifacts, such as false anticorrelated resting-state networks in functional connectivity analyses. Therefore, the efficacy of this technique as a correction tool remains questionable. In this article, we establish that the accuracy of the estimated global signal is determined by the level of global noise (i.e., non-neural noise that has a global effect on the resting-state functional MRI signal). When the global noise level is low, the global signal resembles the resting-state functional MRI time courses of the largest cluster, but not those of the global noise. Using real data, we demonstrate that the global signal is strongly correlated with the default mode network components and has biological significance. These results call into question whether or not global signal regression should be applied. We introduce a method to quantify global noise levels. We show that a criteria for global signal regression can be found based on the method. By using the criteria, one can determine whether to include or exclude the global signal regression in minimizing errors in functional connectivity measures. Copyright © 2012 Wiley Periodicals, Inc.

  3. Going, Going... Gone Global : A study of two companies that want to take their brands abroad

    OpenAIRE

    Stork, Angelica; Leü Byström, Elisabet; Gustafsson, Marie

    2007-01-01

    This is a bachelor thesis within marketing that aims at finding how branding strategies is affected by the market it operates and how it influences the possibilities to create a global brand. This will be carried out by looking at branding strategies, global branding and branding on the emerging markets with comparison to mature markets. The authors will do this by conducting a case study where two companies will be studied, one from an emerging market and one from a mature market. The develo...

  4. Artefactual subcortical hyperperfusion in PET studies normalized to global mean: lessons from Parkinson's disease

    DEFF Research Database (Denmark)

    Borghammer, Per; Cumming, Paul; Aanerud, Joel

    2008-01-01

    not be detected with present instrumentation and typically-used sample sizes. CONCLUSION: Imposing focal decreases on cortical CBF in conjunction with global mean normalization gives rise to spurious relative CBF increases in all of the regions reported to be hyperactive in PD. Since no PET study has reported......AIM: Recent studies of Parkinson's disease (PD) report subcortical increases of cerebral blood flow (CBF) or cerebral metabolic rate of glucose (CMRglc), after conventional normalization to the global mean. However, if the global mean CBF or CMRglc is decreased in the PD group, this normalization...... necessarily generates artificial relative increases in regions unaffected by the disease. This potential bias may explain the reported subcortical increases in PD. To test this hypothesis, we performed simulations with manipulation and subsequently analysis of sets of quantitative CBF maps by voxel...

  5. GLOBAL TO DOMESTIC PRICE TRANSMISSION BETWEEN THE SEGMENTED CEREALS MARKETS: A STUDY OF AFGHAN RICE MARKETS

    Directory of Open Access Journals (Sweden)

    Najibullah Hassanzoy

    2015-10-01

    Full Text Available This paper examines cointegration and the difference in the extent of price transmission, and speed of adjustment between global and domestic prices of high and low quality rice. Unit root tests, cointegration tests and error correction models are employed in the analysis. While there are no comparable studies in the literature, the findings of this study indicate that the dynamics of price transmission may be different between high and low quality rice markets. That is, the extent of price transmission appears to be larger for the global prices of low quality rice whereas the speed of adjustment to the long-run equilibrium may be faster for domestic prices of high quality rice. Moreover, a shock in the global prices of low quality rice may have a long-lasting effect on domestic prices of low quality rice as compared to their high quality counterparts affecting domestic prices of high quality rice.

  6. Global Anthropogenic Phosphorus Loads to Fresh Water, Grey Water Footprint and Water Pollution Levels: A High-Resolution Global Study

    Science.gov (United States)

    Mekonnen, M. M.; Hoekstra, A. Y. Y.

    2014-12-01

    We estimated anthropogenic phosphorus (P) loads to freshwater, globally at a spatial resolution level of 5 by 5 arc minute. The global anthropogenic P load to freshwater systems from both diffuse and point sources in the period 2002-2010 was 1.5 million tonnes per year. China contributed about 30% to this global anthropogenic P load. India was the second largest contributor (8%), followed by the USA (7%), Spain and Brazil each contributing 6% to the total. The domestic sector contributed the largest share (54%) to this total followed by agriculture (38%) and industry (8%). Among the crops, production of cereals had the largest contribution to the P loads (32%), followed by fruits, vegetables, and oil crops, each contributing about 15% to the total. We also calculated the resultant grey water footprints, and relate the grey water footprints per river basin to runoff to calculate the P-related water pollution level (WPL) per catchment.

  7. Global Structural Flexibility of Metalloproteins Regulates Reactivity of Transition Metal Ion in the Protein Core: An Experimental Study Using Thiol-subtilisin as a Model Protein.

    Science.gov (United States)

    Matsuo, Takashi; Kono, Takamasa; Shobu, Isamu; Ishida, Masaya; Gonda, Katsuya; Hirota, Shun

    2018-02-21

    The functions of metal-containing proteins (metalloproteins) are determined by the reactivities of transition metal ions at their active sites. Because protein macromolecular structures have several molecular degrees of freedom, global structural flexibility may also regulate the properties of metalloproteins. However, the influence of this factor has not been fully delineated in mechanistic studies of metalloproteins. Accordingly, we have investigated the relationship between global protein flexibility and the characteristics of a transition metal ion in the protein core using thiol-subtilisin (tSTL) with a Cys-coordinated Cu 2+ ion as a model system. Although tSTL has two Ca 2+ -binding sites, the Ca 2+ -binding status hardly affects its secondary structure. Nevertheless, guanidinium-induced denaturation and amide H/D exchange indicated the increase in the structural flexibility of tSTL by the removal of bound Ca 2+ ions. Electron paramagnetic resonance and absorption spectral changes have revealed that the protein flexibility determines the characteristics of a Cu 2+ ion in tSTL. Therefore, global protein flexibility should be recognized as an important factor that regulates the properties of metalloproteins. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. WE-DE-207B-04: Quantitative Contrast-Enhanced Spectral Mammography Based On Photon-Counting Detectors: A Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Ding, H; Zhou, B; Beidokhti, D; Molloi, S [University of California, Irvine, CA (United States)

    2016-06-15

    Purpose: To investigate the feasibility of accurate quantification of iodine mass thickness in contrast-enhanced spectral mammography. Methods: Experimental phantom studies were performed on a spectral mammography system based on Si strip photon-counting detectors. Dual-energy images were acquired using 40 kVp and a splitting energy of 34 keV with 3 mm Al pre-filtration. The initial calibration was done with glandular and adipose tissue equivalent phantoms of uniform thicknesses and iodine disk phantoms of various concentrations. A secondary calibration was carried out using the iodine signal obtained from the dual-energy decomposed images and the known background phantom thicknesses and densities. The iodine signal quantification method was validated using phantoms composed of a mixture of glandular and adipose materials, for various breast thicknesses and densities. Finally, the traditional dual-energy weighted subtraction method was also studied as a comparison. The measured iodine signal from both methods was compared to the known iodine concentrations of the disk phantoms to characterize the quantification accuracy. Results: There was good agreement between the iodine mass thicknesses measured using the proposed method and the known values. The root-mean-square (RMS) error was estimated to be 0.2 mg/cm2. The traditional weighted subtraction method also predicted a linear correlation between the measured signal and the known iodine mass thickness. However, the correlation slope and offset values were strongly dependent on the total breast thickness and density. Conclusion: The results of the current study suggest that iodine mass thickness can be accurately quantified with contrast-enhanced spectral mammography. The quantitative information can potentially improve the differentiation between benign and malignant legions. Grant funding from Philips Medical Systems.

  9. WE-DE-207B-04: Quantitative Contrast-Enhanced Spectral Mammography Based On Photon-Counting Detectors: A Feasibility Study

    International Nuclear Information System (INIS)

    Ding, H; Zhou, B; Beidokhti, D; Molloi, S

    2016-01-01

    Purpose: To investigate the feasibility of accurate quantification of iodine mass thickness in contrast-enhanced spectral mammography. Methods: Experimental phantom studies were performed on a spectral mammography system based on Si strip photon-counting detectors. Dual-energy images were acquired using 40 kVp and a splitting energy of 34 keV with 3 mm Al pre-filtration. The initial calibration was done with glandular and adipose tissue equivalent phantoms of uniform thicknesses and iodine disk phantoms of various concentrations. A secondary calibration was carried out using the iodine signal obtained from the dual-energy decomposed images and the known background phantom thicknesses and densities. The iodine signal quantification method was validated using phantoms composed of a mixture of glandular and adipose materials, for various breast thicknesses and densities. Finally, the traditional dual-energy weighted subtraction method was also studied as a comparison. The measured iodine signal from both methods was compared to the known iodine concentrations of the disk phantoms to characterize the quantification accuracy. Results: There was good agreement between the iodine mass thicknesses measured using the proposed method and the known values. The root-mean-square (RMS) error was estimated to be 0.2 mg/cm2. The traditional weighted subtraction method also predicted a linear correlation between the measured signal and the known iodine mass thickness. However, the correlation slope and offset values were strongly dependent on the total breast thickness and density. Conclusion: The results of the current study suggest that iodine mass thickness can be accurately quantified with contrast-enhanced spectral mammography. The quantitative information can potentially improve the differentiation between benign and malignant legions. Grant funding from Philips Medical Systems.

  10. Global Ocean Phytoplankton

    Science.gov (United States)

    Franz, B. A.; Behrenfeld, M. J.; Siegel, D. A.; Werdell, P. J.

    2014-01-01

    Marine phytoplankton are responsible for roughly half the net primary production (NPP) on Earth, fixing atmospheric CO2 into food that fuels global ocean ecosystems and drives the ocean's biogeochemical cycles. Phytoplankton growth is highly sensitive to variations in ocean physical properties, such as upper ocean stratification and light availability within this mixed layer. Satellite ocean color sensors, such as the Sea-viewing Wide Field-of-view Sensor (SeaWiFS; McClain 2009) and Moderate Resolution Imaging Spectroradiometer (MODIS; Esaias 1998), provide observations of sufficient frequency and geographic coverage to globally monitor physically-driven changes in phytoplankton distributions. In practice, ocean color sensors retrieve the spectral distribution of visible solar radiation reflected upward from beneath the ocean surface, which can then be related to changes in the photosynthetic phytoplankton pigment, chlorophyll- a (Chla; measured in mg m-3). Here, global Chla data for 2013 are evaluated within the context of the 16-year continuous record provided through the combined observations of SeaWiFS (1997-2010) and MODIS on Aqua (MODISA; 2002-present). Ocean color measurements from the recently launched Visible and Infrared Imaging Radiometer Suite (VIIRS; 2011-present) are also considered, but results suggest that the temporal calibration of the VIIRS sensor is not yet sufficiently stable for quantitative global change studies. All MODISA (version 2013.1), SeaWiFS (version 2010.0), and VIIRS (version 2013.1) data presented here were produced by NASA using consistent Chla algorithms.

  11. A Case Study Approach On Indian Companies And Global Companies Entry In Foreign Markets An Analysis Of Glocalization Strategies

    OpenAIRE

    Fernandes, Semila

    2013-01-01

    The present paper involved a study on Glocal communication strategy adopted by select global companies while foraying into India and Indian companies foray into the foreign markets. Glocalization concept in specific terms implies Think Global and Act Local which has been developed through Japanese business practices. The requirement of this global localization idea arrived in the late 1980s to bridge the gap between local, regional, national, global management of the businesses 20.PROBLEM STA...

  12. Magneto, spectral and thermal studies of lanthanum and lanthanide(3) bromide and nitrate complexes of 2,2'bipyridine mono N-oxide

    International Nuclear Information System (INIS)

    Agarwal, R.K.

    1988-01-01

    Lanthanide(3) bromide and nitrate complexes of 2,2'-bipyridine mono N-oxide (BipyNO) having the composition Ln(BipyNO) 3 Br 3 and Ln(BipyNO) 2 (NO 3 ) 3 (Ln=La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho and Yb) have been prepared and characterized by means of conductance, molecular weight, magnetic and spectral studies. The ligand acts as a bidentate O,N-chelating agent. The coordination number nine or ten for lanthanide ions has been assigned to these complexes. 3 tabs., 25 refs. (author)

  13. On Longitudinal Spectral Coherence

    DEFF Research Database (Denmark)

    Kristensen, Leif

    1979-01-01

    It is demonstrated that the longitudinal spectral coherence differs significantly from the transversal spectral coherence in its dependence on displacement and frequency. An expression for the longitudinal coherence is derived and it is shown how the scale of turbulence, the displacement between ...... observation sites and the turbulence intensity influence the results. The limitations of the theory are discussed....

  14. Differences between downscaling with spectral and grid nudging using WRF

    Directory of Open Access Journals (Sweden)

    P. Liu

    2012-04-01

    Full Text Available Dynamical downscaling has been extensively used to study regional climate forced by large-scale global climate models. During the downscaling process, however, the simulation of regional climate models (RCMs tends to drift away from the driving fields. Developing a solution that addresses this issue, by retaining the large scale features (from the large-scale fields and the small-scale features (from the RCMs has led to the development of "nudging" techniques. Here, we examine the performance of two nudging techniques, grid and spectral nudging, in the downscaling of NCEP/NCAR data with the Weather Research and Forecasting (WRF Model. The simulations are compared against the results with North America Regional Reanalysis (NARR data set at different scales of interest using the concept of similarity. We show that with the appropriate choice of wave numbers, spectral nudging outperforms grid nudging in the capacity of balancing the performance of simulation at the large and small scales.

  15. Study of global control of VIRGO Central Interferometer; Etude du controle global de l'Interferometre Central de VIRGO

    Energy Technology Data Exchange (ETDEWEB)

    Matone, Luca [Paris-11 Univ., 91 Orsay (France)

    1999-10-29

    The VIRGO project for the detection of gravitational waves will first operate in a test configuration, known as the Central Area Interferometer (CITF). The subject of this thesis consists of a study for the global control of this interferometer. In particular, the problems of auto-alignment and acquisition of lock are addressed. First, an investigation of the CITF optical response to longitudinal and angular mirror movements is given. On the basis of this study, we show how the ratio of photodiode signals can be used to detect and control the dark fringe when the CITF is far from its operating point (locked state). Furthermore, we present the simulation results of a quadrant photodiode configuration capable of reconstructing the mirrors' tilts once the CITF is in a locked state. The performance of a control system for the auto-alignment is then given. A study on the mode-cleaner prototype MC30 is then introduced in order to comprehend the process of lock acquisition by a linear feedback system for two different finesse values: F {approx_equal}100 and F {approx_equal} 1600. We define a threshold velocity for the mirrors' relative motion below which acquisition of lock is possible. A phenomenon, referred to as ringing effect, was observed and examined on the MC30 prototype in high finesse. The results of numerical calculations allowed us to fit measurement and estimate from them the cavity finesse as well as the mirrors' relative velocity during the resonance crossing. An empirical formula is then presented capable of determine the relative velocity from the positions of the oscillations' minima and maxima. An algorithm to guide into lock the CITF is then presented, consisting of an iterative procedure of velocity reconstruction and pulse application. A numerical calculation simulated the algorithm, the mirrors' motion, the optical response and the ADCs' process. As a result, acquisition times of the order of one second were observed: an

  16. Spectral features in the cosmic ray fluxes

    Science.gov (United States)

    Lipari, Paolo

    2018-01-01

    The cosmic ray energy distributions contain spectral features, that is narrow energy regions where the slope of the spectrum changes rapidly. The identification and study of these features is of great importance to understand the astrophysical mechanisms of acceleration and propagation that form the spectra. In first approximation a spectral feature is often described as a discontinuous change in slope, however very valuable information is also contained in its width, that is the length of the energy interval where the change in spectral index develops. In this work we discuss the best way to define and parameterize the width a spectral feature, and for illustration discuss some of the most prominent known structures.

  17. Integrated regional assessment of global climatic change. Lessons from the Mackenzie Basin Impact Study (MBIS)

    International Nuclear Information System (INIS)

    Cohen, Stewart J.

    1996-01-01

    This paper outlines the potential role integrated regional assessments of global climatic change scenarios could play in building better links between science and related policy concerns. The concept is illustrated through description of an ongoing case study from Canada-the Mackenzie Basin Impact Study (MBIS). As part of the Government of Canada's Green Plan, the Global Warming Science Program includes a study of regional impacts of global warming scenarios in the Mackenzie Basin, located in northwestern Canada. The MBIS is a six-year program focussing on potential climate-induced changes in the land and water resource base, and the implications of four scenarios of global climatic change on land use and economic policies in this region. These policy issues include interjurisdictional water management, sustainability of native lifestyles, economic development opportunities (agriculture, forestry, tourism, etc.), sustainability of ecosystems and infrastructure maintenance. MBIS is due to be completed in 1997. MBIS represents an attempt to address regional impacts by incorporating a 'family of integrators' into the study framework, and by directly involving stakeholders in planning and research activities. The experience in organizing and carrying out this project may provide some lessons for others interested in organizing regional or country studies

  18. Examination of Spectral Transformations on Spectral Mixture Analysis

    Science.gov (United States)

    Deng, Y.; Wu, C.

    2018-04-01

    While many spectral transformation techniques have been applied on spectral mixture analysis (SMA), few study examined their necessity and applicability. This paper focused on exploring the difference between spectrally transformed schemes and untransformed scheme to find out which transformed scheme performed better in SMA. In particular, nine spectrally transformed schemes as well as untransformed scheme were examined in two study areas. Each transformed scheme was tested 100 times using different endmember classes' spectra under the endmember model of vegetation- high albedo impervious surface area-low albedo impervious surface area-soil (V-ISAh-ISAl-S). Performance of each scheme was assessed based on mean absolute error (MAE). Statistical analysis technique, Paired-Samples T test, was applied to test the significance of mean MAEs' difference between transformed and untransformed schemes. Results demonstrated that only NSMA could exceed the untransformed scheme in all study areas. Some transformed schemes showed unstable performance since they outperformed the untransformed scheme in one area but weakened the SMA result in another region.

  19. Adaptive autoregressive identification with spectral power decomposition for studying movement-related activity in scalp EEG signals and basal ganglia local field potentials

    Science.gov (United States)

    Foffani, Guglielmo; Bianchi, Anna M.; Priori, Alberto; Baselli, Giuseppe

    2004-09-01

    We propose a method that combines adaptive autoregressive (AAR) identification and spectral power decomposition for the study of movement-related spectral changes in scalp EEG signals and basal ganglia local field potentials (LFPs). This approach introduces the concept of movement-related poles, allowing one to study not only the classical event-related desynchronizations (ERD) and synchronizations (ERS), which correspond to modulations of power, but also event-related modulations of frequency. We applied the method to analyze movement-related EEG signals and LFPs contemporarily recorded from the sensorimotor cortex, the globus pallidus internus (GPi) and the subthalamic nucleus (STN) in a patient with Parkinson's disease who underwent stereotactic neurosurgery for the implant of deep brain stimulation (DBS) electrodes. In the AAR identification we compared the whale and the exponential forgetting factors, showing that the whale forgetting provides a better disturbance rejection and it is therefore more suitable to investigate movement-related brain activity. Movement-related power modulations were consistent with previous studies. In addition, movement-related frequency modulations were observed from both scalp EEG signals and basal ganglia LFPs. The method therefore represents an effective approach to the study of movement-related brain activity.

  20. Citizenship and Citizenship Education in a Global Age: Politics, Policies, and Practices in China. Global Studies in Education. Volume 2

    Science.gov (United States)

    Law, Wing-Wah

    2011-01-01

    This book examines issues of citizenship, citizenship education, and social change in China, exploring the complexity of interactions among global forces, the nation-state, local governments, schools, and individuals--including students--in selecting and identifying with elements of citizenship and citizenship education in a multileveled polity.…

  1. Spectral- and size-resolved mass absorption efficiency of mineral dust aerosols in the shortwave spectrum: a simulation chamber study

    Directory of Open Access Journals (Sweden)

    L. Caponi

    2017-06-01

    Full Text Available This paper presents new laboratory measurements of the mass absorption efficiency (MAE between 375 and 850 nm for 12 individual samples of mineral dust from different source areas worldwide and in two size classes: PM10. 6 (mass fraction of particles of aerodynamic diameter lower than 10.6 µm and PM2. 5 (mass fraction of particles of aerodynamic diameter lower than 2.5 µm. The experiments were performed in the CESAM simulation chamber using mineral dust generated from natural parent soils and included optical and gravimetric analyses. The results show that the MAE values are lower for the PM10. 6 mass fraction (range 37–135  ×  10−3 m2 g−1 at 375 nm than for the PM2. 5 (range 95–711  ×  10−3 m2 g−1 at 375 nm and decrease with increasing wavelength as λ−AAE, where the Ångström absorption exponent (AAE averages between 3.3 and 3.5, regardless of size. The size independence of AAE suggests that, for a given size distribution, the dust composition did not vary with size for this set of samples. Because of its high atmospheric concentration, light absorption by mineral dust can be competitive with black and brown carbon even during atmospheric transport over heavy polluted regions, when dust concentrations are significantly lower than at emission. The AAE values of mineral dust are higher than for black carbon (∼ 1 but in the same range as light-absorbing organic (brown carbon. As a result, depending on the environment, there can be some ambiguity in apportioning the aerosol absorption optical depth (AAOD based on spectral dependence, which is relevant to the development of remote sensing of light-absorbing aerosols and their assimilation in climate models. We suggest that the sample-to-sample variability in our dataset of MAE values is related to regional differences in the mineralogical composition of the parent soils. Particularly in the PM2. 5 fraction, we found a strong

  2. Preliminary study of spectral CT imaging in the differential diagnosis of metastatic lymphadenopathy due to various tumors

    International Nuclear Information System (INIS)

    Liu Jingang; Liu Ya; Li Lixin

    2011-01-01

    Objective: To investigate the feasibility of differentiating lymph node metastases of four types of primary tumors (lymphoma, lung adenocarcinoma, lung squamous cell carcinoma and cholangiocarcinoma) using gemstone spectral imaging (GSI). Methods: Three cases with lymphoma (28 lymph node), five cases with lung adenocarcinoma (30 lymph node), four cases with lung squamous cell carcinoma (24 lymph node) and two cases with cholangiocarcinoma (10 lymph node) were evaluated by germstona spectra imaging CT scans. Imaging protocol included unenhanced conventional CT scan (120 kVp), enhanced GSI (80/140 kVp) on arterial phase and conventional CT scan (120 kVp) on portal phase. CT attenuation values of lymph nodes in the monochromatic images at Il sets of keV levels (40- 140 keV, 10 keV step) and the iodine and water contents of these lymph nodes were measured. All results were analyzed with ANOVA and t test. Results: The optimal monochromatic level was 70 keV for the optimal contrast-noise ratio (CNR) of metastatic lymphadenopathy. The CT attenuation values of metastatic lymphadenopathy were (81.36±9.81), (58.33±21.55), (56.47±10.62) and (73.57±4.43) HU, respectively, at 70 keV (F=17.29, P 0.05). The iodine contents of lymphoma, lung adenocarcinoma, lung squamous cell carcinoma and cholangiocarcinoma were (1.93±0.04), (1.16±0.15), (1.25±0.21) and (1.44±0.04) g/L, respectively. The water contents of lymphoma, lung adenocarcinoma, lung squamous cell carcinoma and cholangiocarcinoma were (1029.40±20.85), (1024.98±11.19), (1022.12±12.94) and (1030.87±10.10) g/L, respectively. Except between lung squamous cell carcinoma and lung adenocarcinoma, the differences in the iodine contents of metastatic lymphadenopathy were significant among tumors (P 0.05 ). Conclusions: Although CT spectral imaging fails to differentiate metastatic lymphadenopathy of lung adenocarcinoma and lung squamous cell carcinoma, it is also a promising method of distinguishing metastatic

  3. Spectral- and size-resolved mass absorption efficiency of mineral dust aerosols in the shortwave spectrum: a simulation chamber study

    Science.gov (United States)

    Caponi, Lorenzo; Formenti, Paola; Massabó, Dario; Di Biagio, Claudia; Cazaunau, Mathieu; Pangui, Edouard; Chevaillier, Servanne; Landrot, Gautier; Andreae, Meinrat O.; Kandler, Konrad; Piketh, Stuart; Saeed, Thuraya; Seibert, Dave; Williams, Earle; Balkanski, Yves; Prati, Paolo; Doussin, Jean-François

    2017-06-01

    This paper presents new laboratory measurements of the mass absorption efficiency (MAE) between 375 and 850 nm for 12 individual samples of mineral dust from different source areas worldwide and in two size classes: PM10. 6 (mass fraction of particles of aerodynamic diameter lower than 10.6 µm) and PM2. 5 (mass fraction of particles of aerodynamic diameter lower than 2.5 µm). The experiments were performed in the CESAM simulation chamber using mineral dust generated from natural parent soils and included optical and gravimetric analyses. The results show that the MAE values are lower for the PM10. 6 mass fraction (range 37-135 × 10-3 m2 g-1 at 375 nm) than for the PM2. 5 (range 95-711 × 10-3 m2 g-1 at 375 nm) and decrease with increasing wavelength as λ-AAE, where the Ångström absorption exponent (AAE) averages between 3.3 and 3.5, regardless of size. The size independence of AAE suggests that, for a given size distribution, the dust composition did not vary with size for this set of samples. Because of its high atmospheric concentration, light absorption by mineral dust can be competitive with black and brown carbon even during atmospheric transport over heavy polluted regions, when dust concentrations are significantly lower than at emission. The AAE values of mineral dust are higher than for black carbon (˜ 1) but in the same range as light-absorbing organic (brown) carbon. As a result, depending on the environment, there can be some ambiguity in apportioning the aerosol absorption optical depth (AAOD) based on spectral dependence, which is relevant to the development of remote sensing of light-absorbing aerosols and their assimilation in climate models. We suggest that the sample-to-sample variability in our dataset of MAE values is related to regional differences in the mineralogical composition of the parent soils. Particularly in the PM2. 5 fraction, we found a strong linear correlation between the dust light-absorption properties and elemental

  4. Observation of Individual Particle Morphology, Mineralogy in tandem with Columnar Spectral Aerosol Optics: A Summertime Study over North western India

    Science.gov (United States)

    Mishra, S.; Saha, N.; Singh, S.; Agnihotri, R.; Sharma, C.; Prasad, M. V. S. N.; Arya, B. C.; Naaraayanan, T.; Gautam, S.; Rathore, J. S.; Soni, V. K.; Tawale, J. S.

    2014-12-01

    Limitation over region specific data on dust morphology (particle shape, size) and mineralogy gives rise to uncertainty in estimation of optical and radiative properties of mineral dust (Mishra and Tripathi, 2008; Mishra et al., 2008). To address this issue over Indian arid zone (local source of mineral dust), a short field campaign was organized in Jodhpur, located in Rajasthan, a north western state of India, over seven sites (four in city and three far from city) with varying altitudes in June 2013. Jodhpur lies in vicinity of the Thar Desert of Rajasthan. Particles were collected on pure Tin substrates for individual particle morphological and elemental composition analysis using Scanning Electron Microscope (SEM) equipped with Energy Dispersive Spectrometer (EDS). The morphological parameters (e.g. Aspect ratio; AR, Circulatory parameter; CIR.) were retrieved following Okada et al. (2001) using Image J software. Columnar spectral aerosol optical thickness has been measured by Microtops-II sun photometer for a set of five wavelengths (380 to 1020 nm) over all the sites in tandem with regional aerosol collection. SEM analysis reveals that the particles close to spherical shape (AR range 1.0-1.2) were found to be ~ 18% whereas particles with AR range 1.2-1.4 were found to be abundant (25%) followed with that of AR range 1.4-1.6 and 1.6-1.8 (each ~ 17%) and 1.8-2.0 (~ 14%) while the particles with AR >2 (highly non-spherical) were found to be ~ 8%. Here, it is noteworthy to mention that AR=1 for spherical particle while increasing AR (>1) exhibit increasing non-sphericity of particles. The EDS analysis reveals that 43% particles were observed with low hematite (H ≤ 1%; volume percentage), 24% (H 1-2 %), 14% (H 2-3%), 5% (H 3-4%) and 14% (H >4%). The aforementioned proportions will be extremely useful for simulating the optical and radiative properties of regional aerosols. From the Microtops-II observations, Ångström exponent for spectral interval of 380 to

  5. Study on generation investment decision-making considering multi-agent benefit for global energy internet

    Science.gov (United States)

    Li, Pai; Huang, Yuehui; Jia, Yanbing; Liu, Jichun; Niu, Yi

    2018-02-01

    Abstract . This article has studies on the generation investment decision in the background of global energy interconnection. Generation investment decision model considering the multiagent benefit is proposed. Under the back-ground of global energy Interconnection, generation investors in different clean energy base not only compete with other investors, but also facing being chosen by the power of the central area, therefor, constructing generation investment decision model considering multiagent benefit can be close to meet the interests demands. Using game theory, the complete information game model is adopted to solve the strategies of different subjects in equilibrium state.

  6. Biomarkers and Biological Spectral Imaging

    Science.gov (United States)

    2001-01-23

    G. Sowa, H. H. Mantsch, National Research Council Canada; S. L. Zhang, Unilever Research (USA) 85 Brain tissue charcterization using spectral imaging...image registration and of the expert staff of Hill Top Research in Winnipeg for hosting the hydration study. Financial assistance from Unilever Research

  7. Virtual Competencies and Knowledge Transfer in Global NPD: A Case Study

    Directory of Open Access Journals (Sweden)

    Päivi Lohikoski

    2013-12-01

    Full Text Available Virtual new product development teams are geographically dispersed and cross-functional, yet they work on highly interdependent tasks by communicating electronically in work groups. This virtual interdependence, among other issues, presents new challenges for the management of knowledge transfer in global New Product Development (NPD. In this project, virtual competencies were studied with the use of qualitative methods to assess the most significant issues affecting knowledge transfer in virtual settings in global NPD. As a result, the existing theory regarding virtual competencies and virtual organizations was refined and potential barriers for knowledge transfer were discovered. The success of knowledge workers is crucial for the performance of knowledge-based organizations, which form the basis of our global economy; therefore, this study’s findings are significant.

  8. Isotope tracers in global water and climate studies of the past and present

    International Nuclear Information System (INIS)

    Edwards, T.W.D.; Birks, S.J.; Gibson, J.J.

    2002-01-01

    To date the global distribution of isotopes in modern precipitation has been characterized almost exclusively from the IAEA/WMO GNIP database, although patchiness of GNIP station records in both time and space has limited the potential of isotope hydrology and climate applications in some areas. Herein, we discuss the prospect of utilizing GCMs for simulating global isotope distributions as a supplementary tool for modern and paleoclimate isotope studies to bridge this gap. Such models currently generate reliable zonal isotope fields, and it is anticipated that future enhancements in finescale resolution of GCMs, and incorporation of land-surface feedbacks and topography will allow for future development of a global reanalysis data set ground-truthed by GNIP. Compilation of time-slice maps of past isotope distribution in precipitation from archival records of meteoric waters also offers significant potential to ground-truth paleoclimate simulations extending back tens to hundreds of thousands of years. (author)

  9. The Recent Development of Commercial Services in the Context of Globalization. Case Study: Bucharest

    Directory of Open Access Journals (Sweden)

    Radu Săgeată

    2008-11-01

    Full Text Available The fall of the communist regime and the demise of the bipolar political order have been factors for the development of globalizing connections on the levels of the urban systems in Central and East-European states. The main social impact of this complex phenomenon is the expansion of the diffusion area for the products of global consumerism, which involves the development and the diversification of commercial services. Their localization is still a direct consequence of financial segregation; the determining agent for the degree of penetration of global consumer goods at a local level is the localization of banking investments. Considering this context, this article is correlatively analyzing localization and dispersion factors for financial (banks and banking units and commercial services (malls, international networks of hyper- and supermarkets, restaurants etc., having as case studies the Romanian urban system at a larger scale and its capital city at a micro scale.

  10. Global product development interaction between local networks: A study of the Danish food industry

    DEFF Research Database (Denmark)

    Kristensen, Preben Sander

    A study of the Danish foods industry shows that producers of food products largely ignore home marekt demand in their product development activities. They have built up and maintain development of end-user products in interaction with customers in distant sophisticated markets. Concurrently...... view of actors in the global end-user customer market and companies' euclidean view of actors in thelocal business-to-business market. In pr companies combine these two market views by interacting in networks: The global industrial network links various functions which again are each part of a local...... their development of end-user pr through global interaction. It is precisely by not interacting with home market end-user demand, but rather by deriving an industrial home market demand from changing end-user markets that the complex has avoided being insulated....

  11. Sensitive study of the climatological SST by using ATSR global SST data sets

    Science.gov (United States)

    Xue, Yong; Lawrence, Sean P.; Llewellyn-Jones, David T.

    1995-12-01

    Climatological sea surface temperature (SST) is an initial step for global climate processing monitoring. A comparison has been made by using Oberhuber's SST data set and two years monthly averaged SST from ATSR thermal band data to force the OGCM. In the eastern Pacific Ocean, these make only a small difference to model SST. In the western Pacific Ocean, the use of Oberhuber's data set gives higher climatological SST than that using ATSR data. The SSTs were also simulated for 1992 using climatological SSTs from two years monthly averaged ATSR data and Oberhuber data. The forcing with SST from ATSR data was found to give better SST simulation than that from Oberhuber's data. Our study has confirmed that ATSR can provide accurate monthly averaged global SST for global climate processing monitoring.

  12. Global anomalies in chiral lattice gauge theories

    International Nuclear Information System (INIS)

    Baer, O.

    2000-07-01

    We study global anomalies in a new approach to chiral gauge theories on the lattice, which is based on the Ginsparg-Wilson relation. In this approach, global anomalies make it impossible to define consistently a fermionic measure for the functional integral. We show that a global anomaly occurs in an SU(2) theory if the fundamental representation is used for the fermion fields. The generalization to higher representations is also discussed. In addition we establish a close relation between global anomalies and the spectral flow of the Dirac operator and employ it in a numerical computation to prove the existence of the global SU(2) anomaly in a different way. This method is inspired by an earlier work of Witten who first discovered this type of anomalies in continuum field theory. (orig.)

  13. Global Culture, Learning Style, and Outcome: An Interdisciplinary Empirical Study of International University Students

    Science.gov (United States)

    Strang, Kenneth David

    2010-01-01

    The study examined 2500 business degree students from 21 countries, enrolled at an Australian university, using a survey to assess learning style, which was integrated into a global culture taxonomy. The research hypothesis was that academic outcome could be explained through an interdisciplinary model, by integrating proven theories from…

  14. Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2A. GSFLS visit findings (appendix). Interim report

    International Nuclear Information System (INIS)

    1978-01-01

    This appendix is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This appendix provides the legal/regulatory reference material, supportive of Volume 2 - GSFLS Visit Finding and Evaluations; and certain background material on British Nuclear Fuel Limited

  15. Achieving Globalization of AACSB Accounting Programs with Faculty-Led Study Abroad Education

    Science.gov (United States)

    Meier, Heidi Hylton; Smith, Deborah Drummond

    2016-01-01

    This paper is motivated by recommendations from the American Assembly of Collegiate Schools of Business (AACSB), the Pathways Commission, and NAFSA: Association of International Educators to increase global exposure in the accounting curriculum. Some schools have responded to these demands by offering short-duration, faculty-led, study abroad…

  16. Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2A. GSFLS visit findings (appendix). Interim report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-31

    This appendix is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This appendix provides the legal/regulatory reference material, supportive of Volume 2 - GSFLS Visit Finding and Evaluations; and certain background material on British Nuclear Fuel Limited (BNFL).

  17. Academic Integrity, Remix Culture, Globalization: A Canadian Case Study of Student and Faculty Perceptions of Plagiarism

    Science.gov (United States)

    Evans-Tokaryk, Tyler

    2014-01-01

    This article presents the results of a case study at a Canadian university that used a combination of surveys and focus groups to explore faculty members' and students' perceptions of plagiarism. The research suggests that the globalization of education and remix culture have contributed to competing and contradictory understandings of plagiarism…

  18. Moving beyond the Wall(s): Theorizing Corporate Identity for Global Cultural Studies

    Science.gov (United States)

    Elavsky, C. Michael

    2009-01-01

    This article examines the set of research considerations that went into investigating the relationship between the Bertelsmann Music Group (BMG) and Czech music culture as a means of exploring alternative avenues and frameworks for understanding and doing global cultural studies. Outlining the theoretical and methodological trajectories, as well…

  19. Study with one global crab cavity at IR4 for LHC Upgrade

    CERN Document Server

    Barranco, J; Morita, A; Ralph Assmann, R; Sun, Y; Tomás, R; Weiler, T; Zimmermann, F; CERN. Geneva. BE Department

    2009-01-01

    In this note, we discuss the possible installation and impact on the beam of a single global crab cavity (CC) for both nominal LHC optics and one upgrade LHC optics (Lowbetamax). We also summarize the results on dynamic aperture tracking, luminosity, expected closed orbits, preliminary studies on collimation cleaning efficiency, and the emittance growth due to crab cavity ramping and other sources.

  20. Global Document Delivery, User Studies, and Service Evaluation: The Gateway Experience

    Science.gov (United States)

    Miller, Rush; Xu, Hong; Zou, Xiuying

    2008-01-01

    This study examines user and service data from 2002-2006 at the East Asian Gateway Service for Chinese and Korean Academic Journal Publications (Gateway Service), the University of Pittsburgh. Descriptive statistical analysis reveals that the Gateway Service has been consistently playing the leading role in global document delivery service as well…