Articles de revues : « Instrumental profile »

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Cervellino, Antonio, Cinzia Giannini, Antonietta Guagliardi et Massimo Ladisa. « Disentangling instrumental broadening ». Journal of Applied Crystallography 38, n^o 4 (13 juillet 2005) : 685–87. http://dx.doi.org/10.1107/s0021889805017206.

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A new procedure aimed at disentangling the instrumental profile broadening and the relevant X-ray powder diffraction (XRPD) profile shape is presented. The technique consists of three steps: de-noising by means of wavelet transforms, background suppression by morphological functions and deblurring by a Lucy–Richardson damped deconvolution algorithm. Real XRPD intensity profiles of ceria samples are used to test the performance. Results show the robustness of the method and its capability of efficiently disentangling the instrumental broadening affecting the measurement of the intrinsic physical line profile. These features make the whole procedure an interesting and user-friendly tool for the pre-processing of XRPD data.

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Murakezi, J., Istvan Vince et A. Ludmanj. « Instrumental profile of the Debrecen solar spectrograph ». Serbian Astronomical Journal, n^o 167 (2003) : 81–85. http://dx.doi.org/10.2298/saj0367081m.

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The solar spectrograph of the Heliophysical Observatory at Debrecen, Hungary was investigated to determine its instrumental profile. The measurements were made by using a HeNe laser beam. The widths and asymmetries of the profiles decrease toward higher spectral orders, the most advantageous orders being the third and the fourth ones. To eliminate the broadening of solar lines on account of the instrumental profile, the straightforward iteration method of Gurtovenko has been applied. The efficiency of the method is demonstrated by the simulation of the broadened and corrected spectral line profiles.

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Peleg, Micha. « The instrumental texture profile analysis revisited ». Journal of Texture Studies 50, n^o 5 (28 février 2019) : 362–68. http://dx.doi.org/10.1111/jtxs.12392.

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Welch, Renate, Meg Gerrard et Aletha Huston. « Gender-Related Personality Attributes and Reaction to Success/Failure : An Examination of Mediating Variables ». Psychology of Women Quarterly 10, n^o 3 (septembre 1986) : 221–33. http://dx.doi.org/10.1111/j.1471-6402.1986.tb00748.x.

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The effects of success and failure on task performance, and attributions about performance, were compared for high and low instrumental college women. For the high instrumental group, success facilitated task performance, whereas failure had no debilitating effect; for the low instrumental group, success had no effect on subsequent performance, whereas failure interfered with it. High instrumental women attributed their success primarily to internal factors and their failures to external tactors (the “egotistical” attribution profile), whereas low instrumentar women revealed the opposite profile. The gender-appropriateness of the task had little effect on performance or attribution. Four potential mediators of these differences were investigated: self-esteem, perceived ability, expectancy of success, and attainment value. High-instrumental women's higher perceived ability and performance expectations accounted for their superior task performance, but none of the four mediators accounted for the relationship of instrumentality to attributions.

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Vince, Istvan, et A. Lalovic. « Characteristics of the Belgrade Astronomical Observatory's stellar spectrograph ». Serbian Astronomical Journal, n^o 171 (2005) : 55–63. http://dx.doi.org/10.2298/saj0571055v.

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In this paper the main features of the new SpectraPro-750 spectrograph of Belgrade Astronomical Observatory are described. The instrumental profile of the spectrograph for the 1200 l/mm grating is determined using a fiber optic bundle with fibers arranged in a pseudo-slit pattern. This instrumental profile is compared to the instrumental profiles obtained when the same fiber optic bundle illuminates the entrance slit with different widths. From appropriate instrumental profiles the practical spectral purities and the spectral resolutions for different entrance slit widths are obtained. The variation of the reciprocal linear dispersion with wavelength in the spectral range 350 - 600 nm is determined. A proposal for a link between telescope and the spectrograph is given.

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Scardi, P., L. Lutterotti et P. Maistrelli. « Experimental determination of the instrumental broadening in the Bragg–Brentano geometry ». Powder Diffraction 9, n^o 3 (septembre 1994) : 180–86. http://dx.doi.org/10.1017/s0885715600019187.

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A simple procedure was devised for the preparation of a standard KCl powder to be used for the experimental determination of the instrumental profile in the Bragg–Brentano geometry. The standard was tested on several diffractometers, and narrow Bragg reflections in the range 28°–132° were recorded adopting various experimental conditions. Profiles were modeled with analytical functions, to describe the trend of width and shape of the instrumental profile as a function of the diffraction angle. Some indications were given to perform reliable profile fitting and line broadening analysis; a high resolution setup, obtained by employing narrow slits, large goniometer radius, and a monochromator in the diffracted beam, gives narrow reflections, even though the intensity of the diffracted beam is considerably reduced. The choice of these experimental conditions, which can be achieved using the majority of the commercial instruments, leads to symmetrical profiles, even at relatively low angle (2Θ=28°), which are highly recommended for reliable profile fitting and line broadening analysis.

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Ida, T., H. Hibino et H. Toraya. « Peak profile function for synchrotron X-ray diffractometry ». Journal of Applied Crystallography 34, n^o 2 (1 avril 2001) : 144–51. http://dx.doi.org/10.1107/s0021889800021105.

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A formula of the instrumental function for a high-resolution synchrotron X-ray diffractometer, equipped with a flat crystal analyser and a set of Soller slits for limiting the axial divergence of the diffracted beam, has been derived. The formula incorporates the effects of (i) the axial divergence of the diffracted beam limited by the Soller slits, (ii) the Bragg angle of the flat crystal analyser, and (iii) the tilt angle defined as the deviation of the normal direction of the analyser face from the goniometer plane. The model profile function given by the convolution of a Lorentzian function with the instrumental function has been applied to fit the experimental diffraction peak profiles of standard Si powder (NIST SRM640b) measured with a high-resolution synchrotron X-ray diffractometer, MDS, on beamline BL4B2 at the Photon Factory in Tsukuba. The convolution has been calculated by applying an efficient algorithm for numerical integration. The profile function reproduces not only the experimental profiles measured with a well aligned crystal analyser, but also significantly distorted profiles arising from misalignment of the analyser, withRpvalues within 1.4%, by varying only the instrumental parameter for the tilt angle. It is suggested that further convolution with a Gaussian distribution is practically not necessary for the model instrumental function to fit the data collected with MDS. More rapid computation can be achieved by applying an analytical formula of the profile function, when the tilt angle of the crystal analyser is within about 0.2°.

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Petropavlovskikh, Irina, Koji Miyagawa, Audra McClure-Beegle, Bryan Johnson, Jeannette Wild, Susan Strahan, Krzysztof Wargan et al. « Optimized Umkehr profile algorithm for ozone trend analyses ». Atmospheric Measurement Techniques 15, n^o 6 (28 mars 2022) : 1849–70. http://dx.doi.org/10.5194/amt-15-1849-2022.

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Abstract. The long-term record of Umkehr measurements from four NOAA Dobson spectrophotometers was reprocessed after updates to the instrument calibration procedures. In addition, a new data quality-control tool was developed for the Dobson automation software (WinDobson). This paper presents a comparison of Dobson Umkehr ozone profiles from NOAA ozone network stations – Boulder, the Haute-Provence Observatory (OHP), the Mauna Loa Observatory (MLO), Lauder – against several satellite records, including Aura Microwave Limb Sounder (MLS; ver. 4.2), and combined solar backscatter ultraviolet (SBUV) and Ozone Mapping and Profiler Suite (OMPS) records (NASA aggregated and NOAA cohesive datasets). A subset of satellite data is selected to match Dobson Umkehr observations at each station spatially (distance less than 200 km) and temporally (within 24 h). Umkehr Averaging kernels (AKs) are applied to vertically smooth all overpass satellite profiles prior to comparisons. The station Umkehr record consists of several instrumental records, which have different optical characterizations, and thus instrument-specific stray light contributes to the data processing errors and creates step changes in the record. This work evaluates the overall quality of Umkehr long-term measurements at NOAA ground-based stations and assesses the impact of the instrumental changes on the stability of the Umkehr ozone profile record. This paper describes a method designed to correct biases and discontinuities in the retrieved Umkehr profile that originate from the Dobson calibration process, repair, or optical realignment of the instrument. The Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2) Global Modeling Initiative (M2GMI) and NASA Global Modeling Initiative chemistry transport model (GMI CTM) ozone profile model output matched to station location and date of observation is used to evaluate instrumental step changes in the Umkehr record. Homogenization of the Umkehr record and discussion of the apparent stray light error in retrieved ozone profiles are the focus of this paper. Homogenization of ground-based records is of great importance for studies of long-term ozone trends and climate change.

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MEULLENET, JEAN-FRANCOIS, B. G. LYON, JOHN A. CARPENTER et C. E. LYON. « RELATIONSHIP BETWEEN SENSORY AND INSTRUMENTAL TEXTURE PROFILE ATTRIBUTES ». Journal of Sensory Studies 13, n^o 1 (avril 1998) : 77–93. http://dx.doi.org/10.1111/j.1745-459x.1998.tb00076.x.

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Strong, J. V., B. Mast, A. Midden et E. Leritz. « THE NEUROPSYCHOLOGICAL PROFILE OF OLDER ADULT INSTRUMENTAL MUSICIANS ». Innovation in Aging 2, suppl_1 (1 novembre 2018) : 338. http://dx.doi.org/10.1093/geroni/igy023.1240.

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Russell, Helena. « Profile : Naeem Hussain ». Structural Engineer 100, n^o 10 (1 octobre 2022) : 28–30. http://dx.doi.org/10.56330/awjn6016.

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Clocking up half a century in the international bridges sector, and instrumental in the establishment of Arup's highly regarded bridges department, IStructE Gold Medallist Naeem Hussain has worked on some of the world's most high-profile structures. He reflects on his career in conversation with Helena Russell.

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Cheary, R. W., et A. Coelho. « A fundamental parameters approach to X-ray line-profile fitting ». Journal of Applied Crystallography 25, n^o 2 (1 avril 1992) : 109–21. http://dx.doi.org/10.1107/s0021889891010804.

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A convolution approach to X-ray powder line-profile fitting is developed in which the line shape is synthesized from the Cu Kα emission profile, the dimensions of the diffractometer and the physical variables of the specimen. In addition to the integrated intensities and 2θ positions of the line profiles, the parameters that may be fitted include the receiving-slit width, the receiving-slit length, the X-ray-source size, the angle of divergence of the incident beam, the X-ray attenuation coefficient of the specimen and the crystallite size. This is a self-consistent approach to fitting as the instrumental parameters are usually known by direct measurement. To minimize correlation between refined instrumental parameters, profiles at high and low 2θ values should be fitted simultaneously. The Cu Kα emission profile used in this work is based on recent monolithic double-crystal spectrometer measurements that have identified a doublet structure in both the Kα 1 and Kα 2 components. Fast and accurate convolution procedures have been developed and a mixture of multilinear regression and Gauss–Newton non-linear least squares with numerical differentials is used for fitting the profiles. The method is evaluated by fitting powder diffraction data from well crystallized specimens of MgO and Y3Al5O12 (YAG). Testing has also been carried out by examining the changes in the fitted values after altering various instrumental parameters (e.g. receiving-slit width, detector defocus, receiving-slit length and inclusion of a monochromator).

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Lukáš, P., P. Strunz, V. Davydov et R. Kužel. « Evaluation of substructure parameters by peak profile analysis of high-resolution neutron diffraction spectra ». Powder Diffraction 24, S1 (juin 2009) : S26—S30. http://dx.doi.org/10.1154/1.3134363.

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The peak profile shape analysis has been preferentially used in the evaluation of X-ray and synchrotron powder diffraction pattern. However, neutron diffraction facilities of new generation frequently offer the instrumental resolution high enough to efficiently study the effects of broadening of neutron diffraction profiles. The present paper describes the procedure for a detailed evaluation of Bragg peak shape based on the method of transformed model fitting (TMF) which has been recently developed particularly for the treatment of neutron diffraction profiles. Microstructure modeling is performed in the reciprocal space and the convolution of the model with the instrumental resolution curve is fitted to the profiles recorded in the diffraction experiment.

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Sheer, Miriam. « Dynamics in Beethoven's Late Instrumental Works : A New Profile ». Journal of Musicology 16, n^o 3 (1998) : 358–78. http://dx.doi.org/10.2307/763996.

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Sheer, Miriam. « Dynamics in Beethoven's Late Instrumental Works : A New Profile ». Journal of Musicology 16, n^o 3 (juillet 1998) : 358–78. http://dx.doi.org/10.1525/jm.1998.16.3.03a00050.

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Gozzo, Fabia, A. Cervellino, Matteo Leoni, Paolo Scardi, A. Bergamaschi et B. Schmitt. « Instrumental profile of MYTHEN detector in Debye-Scherrer geometry ». Zeitschrift für Kristallographie 225, n^o 12 (décembre 2010) : 616–24. http://dx.doi.org/10.1524/zkri.2010.1345.

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Ida, T., et H. Toraya. « Deconvolution of the instrumental functions in powder X-ray diffractometry ». Journal of Applied Crystallography 35, n^o 1 (22 janvier 2002) : 58–68. http://dx.doi.org/10.1107/s0021889801018945.

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A novel method to deconvolute the instrumental aberration functions from the experimental powder X-ray data has been developed. The method is based on the combination of scale transformation, interpolation of data and fast Fourier transformation. The effects of axial divergence, flat specimen, sample transparency and spectroscopic profile of the source X-ray are eliminated from the entire observed diffraction pattern in three-step operations. The errors in the deconvoluted data propagated from the statistical uncertainty in the source data are approximated by the reciprocal of the square root of the correlation between the reciprocal of the variance in the source data and the squared instrumental function. The deconvolution of the instrumental aberration functions enables automatic correction of peak shift and line broadening, and supplies narrow and symmetric peak profiles for a well crystallized sample, which can be fitted by a simple model function. It will be useful in preparatory data processing for precise line profile analysis, accurate determination of lattice parameters and whole pattern fitting for crystal structure analysis.

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Correa Mosquera, Ana Ruby, Marta Cecilia Quicazán, Martha Maria Cuenca et Claudia Estella Hernández. « Effect of dehydration on instrumental sensory characteristics of bee pollen ». Afinidad. Journal of Chemical Engineering Theoretical and Applied Chemistry 79, n^o 597 (20 janvier 2023) : 526–32. http://dx.doi.org/10.55815/408303.

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Colombian beekeeping producers and academic sector are developing research projects for using bee products by developing and improving their nutritional and functional quality, especially new food products with bee pollen inclusion. Bee pollen is a promising raw material for the production of functional foods because of its bioactive characteristics. In this work sensory stability of wet pollen, sun dried pollen and cabin dried pollen was evaluated during accelerated storage at 30, 40 and 50°C, taking into account different parameters such as volatile compounds profile by using a commercial electronic nose, fracturability of bee pollen grains with texture analyzer, colour change in CIELAB scale using a commercial colorimeter and water activity. It was found that electronic nose allows differencing bee pollen samples according to their water activity and distinguishing different volatile compounds profiles presented during storage. Bee pollen samples with a high water activity showed volatile compounds profile major changes during storage as well as their colour change. Bee pollen samples with a low water activity presented a change in their smell associated with fat rancidity, which is directly related to the texture.

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CUI, SHANSHAN, KAI YU, ZHUOYAN HU et GUOJING WEI. « TEXTURE PROFILE OF HERBAL GEL AFFECTED BY INSTRUMENTAL PARAMETERS AND CORRELATIONS OF INSTRUMENTAL AND SENSORY EVALUATION ». Journal of Texture Studies 42, n^o 5 (21 mars 2011) : 349–58. http://dx.doi.org/10.1111/j.1745-4603.2011.00289.x.

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Cheng, Lijing, John Abraham, Gustavo Goni, Timothy Boyer, Susan Wijffels, Rebecca Cowley, Viktor Gouretski et al. « XBT Science : Assessment of Instrumental Biases and Errors ». Bulletin of the American Meteorological Society 97, n^o 6 (1 juin 2016) : 924–33. http://dx.doi.org/10.1175/bams-d-15-00031.1.

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Abstract Expendable bathythermograph (XBT) data were the major component of the ocean temperature profile observations from the late 1960s through the early 2000s, and XBTs still continue to provide critical data to monitor surface and subsurface currents, meridional heat transport, and ocean heat content. Systematic errors have been identified in the XBT data, some of which originate from computing the depth in the profile using a theoretically and experimentally derived fall-rate equation (FRE). After in-depth studies of these biases and discussions held in several workshops dedicated to discussing XBT biases, the XBT science community met at the Fourth XBT Science Workshop and concluded that XBT biases consist of 1) errors in depth values due to the inadequacy of the probe motion description done by standard FRE and 2) independent pure temperature biases. The depth error and temperature bias are temperature dependent and may depend on the data acquisition and recording system. In addition, the depth bias also includes an offset term. Some biases affecting the XBT-derived temperature profiles vary with manufacturer/probe type and have been shown to be time dependent. Best practices for historical XBT data corrections, recommendations for future collection of metadata to accompany XBT data, impact of XBT biases on scientific applications, and challenges encountered are presented in this manuscript. Analysis of XBT data shows that, despite the existence of these biases, historical XBT data without bias corrections are still suitable for many scientific applications, and that bias-corrected data can be used for climate research.

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Leoni, Matteo, Paolo Scardi et J. Ian Langford. « Characterization of standard reference materials for obtaining instrumental line profiles ». Powder Diffraction 13, n^o 4 (décembre 1998) : 210–15. http://dx.doi.org/10.1017/s0885715600010125.

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Standard Reference Materials (SRMs) for determining instrumental line profiles should not exhibit measurable broadening from structural imperfections, but owing the effects of sample transparency and other geometrical effects, the quality of possible SRMs cannot necessarily be assessed satisfactorily with data from a conventional divergent-beam diffractometer. The problem of transparency can be avoided if parallel beam optics is used, as for instance on a synchrotron radiation powder diffraction station employing Parrish (Soller-type receiving slit assembly) geometry. Data from such a configuration are used to compare three SRMs commonly used in line-profile analysis.

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Padmanabh, Prajwal V., Ewan D. Barr, David J. Champion, Ramesh Karuppusamy, Michael Kramer, Axel Jessner et Patrick Lazarus. « Revisiting profile instability of PSR J1022+1001 ». Monthly Notices of the Royal Astronomical Society 500, n^o 1 (14 octobre 2020) : 1178–87. http://dx.doi.org/10.1093/mnras/staa3174.

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ABSTRACT Millisecond pulsars in timing arrays can act as probes for gravitational wave detection and improving the Solar system ephemerides among several other applications. However, the stability of the integrated pulse profiles can limit the precision of the ephemeris parameters and in turn the applications derived from it. It is thus crucial for the pulsars in the array to have stable integrated pulse profiles. Here we present evidence for long-term profile instability in PSR J1022+1001 which is currently included in the European and Parkes pulsar timing arrays. We apply a new evaluation method to an expanded data set ranging from the Effelsberg Pulsar Observing System backend used in the 1990s to that of data from the current PSRIX backend at the Effelsberg Radio Telescope. We show that this intrinsic variability in the pulse shape persists over time-scales of years. We investigate if systematic instrumental effects like polarization calibration or signal propagation effects in the interstellar medium causes the observed profile instability. We find that the total variation cannot be fully accounted for by instrumental and propagation effects. This suggests additional intrinsic effects as the origin for the variation. We finally discuss several factors that could lead to the observed behaviour and comment on the consequent implications.

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Popa, N. C., et D. Balzar. « An analytical approximation for a size-broadened profile given by the lognormal and gamma distributions ». Journal of Applied Crystallography 35, n^o 3 (16 mai 2002) : 338–46. http://dx.doi.org/10.1107/s0021889802004156.

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The size-broadened profile given by the lognormal and gamma size distributions of spherical crystallites is considered. An analytical approximation for the size-broadened profile is derived that can be analytically convolved with the strain-broadened and instrumental-broadened profiles. The method is tested on two CeO2powders; one shows `super-Lorentzian' profiles that were successfully modelled under the assumption of a broad lognormal size distribution. It is shown that the Voigt function, as a common model for a size-broadened profile, fails for both very narrow and broad size distributions. It is argued that the size-broadened line profile is not very sensitive to variations in size distribution and that an apparent domain size or even column-length distribution function can correspond to significantly different size distributions.

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PONS, M., et S. M. FISZMAN. « INSTRUMENTAL TEXTURE PROFILE ANALYSIS WITH PARTICULAR REFERENCE TO GELLED SYSTEMS ». Journal of Texture Studies 27, n^o 6 (décembre 1996) : 597–624. http://dx.doi.org/10.1111/j.1745-4603.1996.tb00996.x.

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MacKay, David B. « Probabilistic scaling analyses of sensory profile, instrumental and hedonic data ». Journal of Chemometrics 19, n^o 3 (2005) : 180–90. http://dx.doi.org/10.1002/cem.921.

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Guo, Yanjun, Pamela M. Rist, Maria Sabater-Lleal, Paul de Vries, Nicholas Smith, Paul M. Ridker, Tobias Kurth et Daniel I. Chasman. « Association Between Hemostatic Profile and Migraine ». Neurology 96, n^o 20 (1 avril 2021) : e2481-e2487. http://dx.doi.org/10.1212/wnl.0000000000011931.

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ObjectiveTo assess support for a causal relationship between hemostatic measures and migraine susceptibility using genetic instrumental analysis.MethodsTwo-sample Mendelian randomization instrumental analyses leveraging available genome-wide association study (GWAS) summary statistics were applied to hemostatic measures as potentially causal for migraine and its subtypes, migraine with aura (MA) and migraine without aura (MO). Twelve blood-based measures of hemostasis were examined, including plasma level or activity of 8 hemostatic factors and 2 fibrinopeptides together with 2 hemostasis clinical tests.ResultsThere were significant instrumental effects between increased coagulation factor VIII activity (FVIII; odds ratio [95% confidence interval] 1.05 [1.03, 1.08]/SD, p = 6.08 × 10−05), von Willebrand factor level (vWF; 1.05 [1.03, 1.08]/SD, p = 2.25 × 10−06), and phosphorylated fibrinopeptide A level (1.13 [1.07, 1.19]/SD, p = 5.44 × 10−06) with migraine susceptibility. When extended to migraine subtypes, FVIII, vWF, and phosphorylated fibrinopeptide A showed slightly stronger effects with MA than overall migraine. Fibrinogen level was inversely linked with MA (0.76 [0.64, 0.91]/SD, p = 2.32 × 10−03) but not overall migraine. None of the hemostatic factors was linked with MO. In sensitivity analysis, effects for fibrinogen and phosphorylated fibrinopeptide A were robust, whereas independent effects of FVIII and vWF could not be distinguished, and FVIII associations were potentially affected by pleiotropy at the ABO locus. Causal effects from migraine to the hemostatic measures were not supported in reverse Mendelian randomization. However, MA was not included due to lack of instruments.ConclusionsThe findings support potential causality of increased FVIII, vWF, and phosphorylated fibrinopeptide A and decreased fibrinogen in migraine susceptibility, especially for MA, potentially revealing etiologic relationships between hemostasis and migraine.

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Zuev, A. D. « Calculation of the instrumental function in X-ray powder diffraction ». Journal of Applied Crystallography 39, n^o 3 (10 mai 2006) : 304–14. http://dx.doi.org/10.1107/s0021889806005693.

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A new method for calculating the total instrumental function of a conventional Bragg–Brentano diffractometer has been developed. The method is based on an exact analytical solution, derived from diffraction optics, for the contribution of each incident ray to the intensity registered by a detector of limited size. Because an incident ray is determined by two points (one is related to the source of the X-rays and the other to the sample) the effects of the coupling of specific instrumental functions, for example, equatorial and axial divergence instrumental functions, are treated together automatically. The intensity at any arbitrary point of the total instrumental profile is calculated by integrating the intensities over two simple rectangular regions: possible point positions on the source and possible point positions on the sample. The effects of Soller slits, a monochromator and sample absorption can also be taken into account. The main difference between the proposed method and the convolutive approach (in which the line profile is synthesized by convolving the specific instrumental functions) lies in the fact that the former provides an exact solution for the total instrumental function (exact solutions for specific instrumental functions can be obtained as special cases), whereas the latter is based on the approximations for the specific instrumental functions, and their coupling effects after the convolution are unknown. Unlike the ray-tracing method, in the proposed method the diffracted rays contributing to the registered intensity are considered as combined (part of the diffracted cone) and, correspondingly, the contribution to the instrumental line profile is obtained analytically for this part of the diffracted cone and not for a diffracted unit ray as in ray-tracing simulations.

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Ida, T., H. Hibino et H. Toraya. « Deconvolution of instrumental aberrations for synchrotron powder X-ray diffractometry ». Journal of Applied Crystallography 36, n^o 2 (15 mars 2003) : 181–87. http://dx.doi.org/10.1107/s0021889802021131.

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A method to remove the effects of instrumental aberrations from the whole powder diffraction pattern measured with a high-resolution synchrotron powder diffractometer is presented. Two types of asymmetry in the peak profiles caused by (i) the axial-divergence aberration of the diffractometer (diffractometer aberration) and (ii) the aberration of the monochromator and focusing optics on the beamline (beamline aberration) are both taken into account. The method is based on the whole-pattern deconvolution by Fourier technique combined with the abscissa-scale transformation appropriate for each instrumental aberration. The experimental powder diffraction data of LaB6(NIST SRM660) measured on beamline BL-4B2at the Photon Factory in Tsukuba have been analysed by the method. The formula of the scale transformation for the diffractometer aberration hasa prioribeen derived from the instrumental function with geometric parameters of the optics. The strongly deformed experimental peak profiles at low diffraction angles have been transformed to sharp peak profiles with less asymmetry by the deconvolution of the diffractometer aberration. The peak profiles obtained by the deconvolution of the diffractometer aberration were modelled by an asymmetric model profile function synthesized by the convolution of the extended pseudo-Voigt function and an asymmetric component function with an empirical asymmetry parameter, which were linearly dependent on the diffraction angle. Fairly symmetric peak profiles have been obtained by further deconvolution of the empirically determined asymmetric component of the beamline aberration.

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Ida, T., S. Shimazaki, H. Hibino et H. Toraya. « Diffraction peak profiles from spherical crystallites with lognormal size distribution ». Journal of Applied Crystallography 36, n^o 5 (8 septembre 2003) : 1107–15. http://dx.doi.org/10.1107/s0021889803011580.

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An efficient and accurate method to evaluate the theoretical diffraction peak profiles from spherical crystallites with lognormal size distribution (SLN profile) is presented. Precise results can be obtained typically by an eight-term numerical integral for any values of the parameters, by applying an appropriate substitution of the variable to the integral formula. The calculated SLN profiles have been verified by comparison with those calculated by inverse Fourier transform from the exact analytical solution of the Fourier-transformed SLN profile. It has been found that the shape of the SLN profile strongly depends on the variance of size distribution. When the logarithmic standard deviation ω of the size distribution is close to 0.76, the SLN profile becomes close to a Lorentzian profile, and `super-Lorentzian' profiles are predicted for larger values of ω, as has been concluded by Popa & Balzar [J. Appl. Cryst.(2002),35, 338–346]. The intrinsic diffraction peak profiles of an SiC powder sample obtained by deconvolution of the instrumental function have certainly shown `super-Lorentzian' line profiles, and they are well reproduced by the SLN profile for the value ω = 0.93.

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Marinov, Svetlin, Ognyan Alipiev et Toni Uzunov. « Interference of the profiles when meshing internal straight splines with gear shapers ». MATEC Web of Conferences 287 (2019) : 01015. http://dx.doi.org/10.1051/matecconf/201928701015.

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The possibilities for cutting internal straight splines with gear shapers by internal meshing, without interference between meshed profiles, are shown in this article. The interference is an undesirable occurrence whereby the straight profile of the splines and the instrumental contour intersect with each other beyond the meshing line. As a result, the shaper teeth cut off a part of the splines’ straight profile and they are made with some defects. The research shows that the undesirable interference depends directly on the parameters of the splined opening and the number of shaper teeth. Also, it is determined that the interference can be avoided by reducing the number of shaper teeth and the height of the splines. Furthermore, the maximum number of shaper teeth for all standard splines for which the interference is absent, are defined in the article. The results are confirmed by computer simulations of the corresponding instrumental meshing.

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Oranska, O. I., Yu I. Gornikov, V. M. Gun’ko et A. V. Brichka. « On the use of model diffraction profiles in the microstructure analysis of nanocrystalline metal oxides based on powder x-ray diffraction data ». SURFACE 14(29) (30 décembre 2022) : 148–58. http://dx.doi.org/10.15407/surface.2022.14.148.

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The study of the microstructure of nanocrystalline substances by the method of powder diffractometry based on the physical broadening of diffraction lines involves the use of diffraction data of standard polycrystalline samples, preferably, one nature with the test samples with the size of crystallites exceeding 100 nm. In the absence of such standards, researchers resort to the existing dependence of the width of diffraction peaks on the angle of diffraction for the standard sample or the construction of theoretical instrumental profiles due to the collimation parameters of x -rays used. In this paper a comparative study of the microstructure of nanocrystalline titanium oxide (anatase), tin oxide iron oxide (magnetite), synthesized in various ways, using several methods of analysis of powder diffractograms, was carried out. To evaluate the average crystallite sizes of the studied oxides, the Sherer equation with a graphical method of determining the width of instrumental profile and the influence of dublet radiation was chosen. Methods of profile analysis of diffraction spectra, such as a method of whole profile modeling of powder diffractograms (WPPM) and the chord method, were used to construct crystallite size distribution functions and determine the average size of crystallites of the oxides. Modeling of instrumental diffraction profiles of titanium, tin and iron oxides was performed using X -rays collimation parameters determinated using a polycrystalline silicon as standard and pseudo -Voigt function, which best describes the form of diffraction peak. The crystallite size distribution functions were constructed by means of WPPM and chords methods based on the instrumental profiles. It has been found that the values of average size of the crystallites, obtained by the methods of Sherer, WPPM and chords, differ within the one order of magnitude for each oxide. Thus, for titanium oxide this value is within 12-18 nm, for tin oxide within 7-10 nm, the iron oxide of iron within 9-12 nm. Analysis of size crystallite distribution functions and average sizes of the crystallites of the studied oxides showed the advisability of using different methods of studying microstructure to clarify the true type of the size crystallites distribution and establish its connection with the conditions and the synthesis method.

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Denney, Jonathan J., Gerard S. Mattei, Marcus H. Mendenhall, James P. Cline, Peter G. Khalifah et Brian H. Toby. « Determination of physically based pseudo-Voigt powder diffraction profile terms from the fundamental parameters approach ». Journal of Applied Crystallography 55, n^o 2 (11 mars 2022) : 289–95. http://dx.doi.org/10.1107/s1600576722001169.

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A methodology is developed where a fundamental parameters approach (FPA) description of a laboratory powder diffraction instrument (configured in divergent-beam Bragg–Brentano geometry) is used to determine GSAS-II profile parameters for peak asymmetry and instrumental peak widths. This allows the instrumental contribution to peak shapes to be robustly determined directly from a physical description of the instrument, even though GSAS-II does not directly implement FPA for peak shape computation. The FPA-derived parameters can be used as the starting point for instrument characterization, or to characterize sample broadening without the use of a standard to determine the instrument profile function. This new method can facilitate generation of training sets for machine learning. A plot is generated that shows the differences between the two approaches, demonstrating upper bounds for the accuracy of the GSAS-II profile model for a particular instrumental configuration.

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Smrke, Urška, Nejc Plohl et Izidor Mlakar. « Aging Adults’ Motivation to Use Embodied Conversational Agents in Instrumental Activities of Daily Living : Results of Latent Profile Analysis ». International Journal of Environmental Research and Public Health 19, n^o 4 (18 février 2022) : 2373. http://dx.doi.org/10.3390/ijerph19042373.

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The rapidly increasing share of ageing adults in the population drives the need and interest in assistive technology, as it has the potential to support ageing individuals in living independently and safely. However, technological development rarely reflects how needs, preferences, and interests develop in different ways while ageing. It often follows the strategy of “what is possible” rather than “what is needed” and “what preferred”. As part of personalized assistive technology, embodied conversational agents (ECAs) can offer mechanisms to adapt the technological advances with the stakeholders’ expectations. The present study explored the motivation among ageing adults regarding technology use in multiple domains of activities of daily living. Participants responded to the questionnaire on the perceived importance of instrumental activities of daily living and acceptance of the idea of using ECAs to support them. Latent profile analysis revealed four profiles regarding the motivation to use ECAs (i.e., a low motivation profile, two selective motivation profiles with an emphasis on physical and psychological well-being, and a high motivation profile). Profiles were compared in terms of their acceptance of ECA usage in various life domains. The results increase the knowledge needed in the development of assistive technology adapted to the expectations of ageing adults.

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Rodríquez-Carvajal, Juan, et T. Roisnel. « Line Broadening Analysis Using FullProf* : Determination of Microstructural Properties ». Materials Science Forum 443-444 (janvier 2004) : 123–26. http://dx.doi.org/10.4028/www.scientific.net/msf.443-444.123.

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A short account of the methodology used within FullProf to extract average micro-structural properties from the analysis of broadened lines of constant wavelength diffraction patterns is presented. The approach is based on the Voigt approximation and can be combined with the Rietveld method as well as with the profile matching (Le Bail fit) procedure. Both the instrumental and sample profiles are supposed to be well described by Voigt functions. To get reliable sample parameters a good knowledge of the Instrumental Resolution Function (IRF) is needed. Only a phenomenological treatment, in terms of coherent size domains and strains due to structural defects, is performed.

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Johnson, Marc. « Observations on Dr. Peleg's article : The instrumental texture profile analysis revisited ». Journal of Texture Studies 50, n^o 5 (29 mai 2019) : 383–85. http://dx.doi.org/10.1111/jtxs.12407.

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Popa, N. C., et I. Ionita. « The instrumental profile for a neutron powder diffractometer in focusing geometry ». Physica B : Condensed Matter 276-278 (mars 2000) : 192–94. http://dx.doi.org/10.1016/s0921-4526(99)01243-0.

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LUCISANO, M., C. POMPEI et E. CASIRAGHI. « TEXTURE EVALUATION OF SOME ITALIAN CHEESES BY INSTRUMENTAL TEXTURE PROFILE ANALYSIS ». Journal of Food Quality 10, n^o 2 (avril 1987) : 73–89. http://dx.doi.org/10.1111/j.1745-4557.1987.tb00291.x.

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Bottari, Carolina, Clément Dassa, Constant Rainville et Élisabeth Dutil. « A Generalizability Study of the Instrumental Activities of Daily Living Profile ». Archives of Physical Medicine and Rehabilitation 91, n^o 5 (mai 2010) : 734–42. http://dx.doi.org/10.1016/j.apmr.2009.12.023.

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Ohno, Katsumi, Hirosi Harada, Toshihiro Yamagata, Michio Yamazaki et Kazumasa Ohsumi. « X-ray Diffractometric Determination of Lattice Misfit Between γ and γ' Phases in Ni-Base Superalloys ». Advances in X-ray Analysis 32 (1988) : 365–75. http://dx.doi.org/10.1154/s037603080002067x.

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AbstractThe lattice misfits between γ and γ' phases in Ni-base superalloys (single crystal) were accurately determined for filings of specimens by using both a conventional X-ray tube focusing diffractometer(CXRFD) and a synchrotron-radiation parallel beam X-ray diffractometer (SRPXRD). All reflection peaks measured with the CXRFD were in a cluster of overlapping peaks because of the very small differences in the lattice parameters of both phases and the instrumental broadening due to X-ray optics including the spectral distribution of Xray source such as CuKα doublet. The deconvolution method was applied to remove the instrumental broadening from the peaks measured with the CXRFD. The window functions for the deconvolution method were calculated from CuKα doublet reflection of Si standard by a nonlinear least-square method.The instrumental broadening of SRPXRD was much smaller than that of CXRFD since the monochromatic X-rays produced single peak profiles and constant profile shape over a wide 2θ range. A profile fitting with a pseudo-Voigt function was used to determine 2θ angles to 0.0005 deg. for the synchrotron powder data. The peak angle and shape reflected from γ' phases in γ-matrix and those fron electrochemically extracted γ'-phase were significantly different.

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Rebuffi, Luca, Manuel Sánchez del Río, Edoardo Busetto et Paolo Scardi. « Understanding the instrumental profile of synchrotron radiation X-ray powder diffraction beamlines ». Journal of Synchrotron Radiation 24, n^o 3 (20 avril 2017) : 622–35. http://dx.doi.org/10.1107/s1600577517005434.

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A Monte Carlo algorithm has been developed to calculate the instrumental profile function of a powder diffraction synchrotron beamline. Realistic models of all optical elements are implemented in a ray-tracing software. The proposed approach and the emerging paradigm have been investigated and verified for several existing X-ray powder diffraction beamlines. The results, which can be extended to further facilities, show a new and general way of assessing the contribution of instrumental broadening to synchrotron radiation data, based on ab initio simulations.

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Rascle, Olivier, et Genevieve Coulomb. « AGGRESSION IN YOUTH HANDBALL : RELATIONSHIPS BETWEEN GOAL ORIENTATIONS AND INDUCED MOTIVATIONAL CONTEXT ». Social Behavior and Personality : an international journal 31, n^o 1 (1 janvier 2003) : 21–33. http://dx.doi.org/10.2224/sbp.2003.31.1.21.

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This study examined the effects of the interaction between young male handball players'goal orientations (13-15 years of age) and induced motivational context (individual vs. collective performance) on observed aggression. 10 handball games, 5 under each induced motivational context, were videotaped and observed on monitor by means of a grid allowing the distinction between instrumental and hostile aggression. The results indicated (a) significant effects of the Induced motivational context and the Motivational Profile; and (b) an interaction between Induced motivational context and Motivational Profile on observed instrumental aggression. In a collective performance-induced context, players classified as being strongly both task- and ego-goal oriented displayed more instrumental aggression compared with those classified as having strong task-goal orientation and low ego-goal orientation.

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Szkop, Artur, Alnilam Fernandes et Aleksander Pietruczuk. « Towards a Multi-Instrumental Approach to Closing Aerosol Optical Extinction Profiles ». Atmosphere 13, n^o 9 (6 septembre 2022) : 1443. http://dx.doi.org/10.3390/atmos13091443.

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A novel methodology is formulated and investigated on test cases for the reconstruction of complete vertical aerosol extinction profiles in which a synergy of remote, in-situ, and airborne measurements is utilized. The GRASP Open aerosol retrieval algorithm is supplied with remote LIDAR and sunphotometer data to obtain aerosol extinction profiles within the LIDAR’s operation range for coarse and fine aerosol modes separately. These are supplemented with ground-based in-situ measurements of particle size distribution that are translated to coarse and fine aerosol extinction coefficients with the use of Mie theory. UAV-based observations with optical particle counters are included to add information on vertical aerosol variability in the near-surface region. The profiles are closed with an analytical interpolation that is fine-tuned to produce continuous and smooth extinction profiles throughout the whole troposphere that are in agreement with columnar aerosol optical depth measurements. We present the possibility of reconstructing a complete and calibrated aerosol extinction profile, based on the case studies at a Central European background station. We include data-denial experiments to show that the inclusion of UAV-based measurements improves such reconstructions by providing crucial information on aerosol profiles near the ground. The proposed methodology can prove to be a potent tool for studies of aerosol concentration and evolution, especially when the majority of the pollution resides near the surface. Such conditions are prevalent in many highly industrialized regions, including central and southern Poland.

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Fawcett, T. G., C. E. Crowder, S. J. Brownell, Y. Zhang, C. Hubbard, W. Schreiner, G. P. Hamill et al. « Establishing an Instrumental Peak Profile Calibration Standard for Powder Diffraction Analyses : International Round Robin Conducted by the JCPDS-ICDD and the U.S. National Bureau of Standards ». Powder Diffraction 3, n^o 4 (décembre 1988) : 209–18. http://dx.doi.org/10.1017/s0885715600013506.

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With the explosive growth in the number of highly automated powder diffraction systems, many types of analyses which were previously considered a specialty analysis are now performed on a routine basis. Algorithms have been developed for measuring peak profiles from which crystallite sizes, residual microstrain, and X-ray crystal structure (Rietveld techniques for example) can be determined. However, these techniques require an instrumental peak profile calibration standard to correct the experimental data for instrumental broadening due to the system optics.Significant problems are encountered when laboratories try to cross-correlate or reproduce published data due to the lack of a common reference material for instrumental calibration. This is particularly distressing in microstrain and crystallite size calculations which can be dramatically affected by a poor choice of standard materials. Microstrain and crystallite size measurement are becoming increasingly important for the characterization of advanced materials and catalysts.

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Verbova, Yu. « THE SPECIFICITY OF VALUE ORIENTATIONS OF STUDENTS IN TECHNICAL PROFILE COLLEGES ». Psychology and Personality, n^o 1 (20 mai 2019) : 101–10. http://dx.doi.org/10.33989/2226-4078.2019.1.163990.

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The article is aimed to reveal the specificity of colleges technical profile student’s value orientations. Theoretical analysis of modern scientific researches of value orientation’s role in the college student’s professional becoming are presented. The results of empirical research of value-motivational types, terminal and instrumental values of college students are analyzed. the prevailing value orientations of the technical profile college students are the focus on improving material well-being, achievement of social status and recognition, achievement in various spheres of life and manifestation of autonomy are described. The role of instrumental values of freedom, sense of life, self-esteem, creativity, self-discipline and authority in student’s learning activity are represented.

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Lutterotti, Luca, Henry Pillière, Christophe Fontugne, Philippe Boullay et Daniel Chateigner. « Full-profile search–match by the Rietveld method ». Journal of Applied Crystallography 52, n^o 3 (14 mai 2019) : 587–98. http://dx.doi.org/10.1107/s160057671900342x.

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A new search–match procedure has been developed and tested which, in contrast to previously existing methods, does not use a set of lines identified from a diffraction pattern, but an optimized Rietveld fitting on the raw data. Modern computers with multicore processors allow the routine to be fast enough to perform the entire search in a reasonable time using quite large databases of crystal structures. The search–match is done using the crystal structures for all phases and the instrumental geometry, and as such can be applied to every kind of diffraction experiment, including X-rays, thermal/time-of-flight neutrons and electrons. The methodology can also be applied to nanocrystalline samples for which peak identification may be a problem. A web interface has been developed to permit easy testing and evaluation of the procedure. The quality of the results mainly depends on the availability of the sought phase in the structure database. The method permits not only phase identification but also a rapid quantification of the phases and their gross microstructural features, provided the instrumental function is known.

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Masson, O., E. Dooryhée et A. N. Fitch. « Instrument line-profile synthesis in high-resolution synchrotron powder diffraction ». Journal of Applied Crystallography 36, n^o 2 (15 mars 2003) : 286–94. http://dx.doi.org/10.1107/s0021889803001031.

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An accurate method for synthesizing the instrumental line profile of high-resolution synchrotron powder diffraction instruments is presented. It is shown that the instrumental profile can be modelled by the convolution of four physical aberration functions: the equatorial intensity distribution, the monochromator and analyser transfer functions, and the axial divergence aberration function. Moreover, each equatorial aberration is related to an angle-independent function by a scale transform factor. The principles of the instrument line-profile calculation are general. They are applied in the case of the angle-dispersive powder X-ray diffraction beamline BM16 at the ESRF. The effects of each optical element on the overall instrument profile are discussed and the importance of the quality of the different optical elements of the instrument is emphasized. Finally, it is shown that the high resolution combined with the precise modelling of the instrument profile shape give access to a particle size as large as 3 µm.

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Dolik, Kamil, et Mariusz S. Kubiak. « Instrumental test of texture profile analysis in the study of selected food quality ». Engineering Sciences And Technologies, n^o 3(10) (2013) : 35–44. http://dx.doi.org/10.15611/nit.2013.3.03.

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Pedersen, Darhl M. « Perceived Traits of Male and Female Athletes ». Perceptual and Motor Skills 85, n^o 2 (octobre 1997) : 547–50. http://dx.doi.org/10.2466/pms.1997.85.2.547.

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Profiles of personality traits for male and female athletes were obtained from 133 men and 71 women raters. Traits were rated using a 7-point semantic differential with 11 bipolar items. A profile analysis showed that the profiles of the traits were distinct. There were no significant differences in the ratings by men and women raters. Male athletes were rated as more active, aggressive, competitive, dominating, controlling, instrumental, and public. Female athletes were rated as more goal-oriented, organized, and rule-governed.

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Turneaure, Stefan J., et Y. M. Gupta. « Real-time microstructure of shock-compressed single crystals from X-ray diffraction line profiles ». Journal of Applied Crystallography 44, n^o 3 (6 mai 2011) : 574–84. http://dx.doi.org/10.1107/s0021889811012908.

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Methods to obtain and analyze high-resolution real-time X-ray diffraction (XRD) measurements from shock-compressed single crystals are presented. Procedures for extracting microstructural information – the focus of this work – from XRD line profiles are described. To obtain quantitative results, careful consideration of the experimental geometry is needed, including the single-crystal nature of the sample and the removal of instrumental broadening. These issues are discussed in detail. Williamson–Hall (WH) and profile synthesis (PS) analysis procedures are presented. More accurate than WH, the PS procedure relies on a forward calculation in which a line profile is synthesized by convoluting the instrumental line profile with a line profile determined from a diffraction simulation. The diffraction simulation uses the actual experimental geometry and a model microstructure for the shocked crystal. The shocked-crystal microstructural parameters were determined by optimizing the match between the synthesized and measured line profiles. XRD measurements on an Al crystal, shocked along [100] to 7.1 GPa using plate-impact loading, are used to demonstrate the WH and PS analysis methods. In the present analysis, the microstructural line broadening arises because of a distribution of longitudinal elastic microstrains. The WH analysis resulted in FWHM longitudinal microstrain distributions of 0.22 and 0.38% for Lorentzian and Gaussian line shape assumptions, respectively. The optimal FWHM longitudinal microstrain for the PS method was 0.35% with a pseudo-Voigt distribution (40% Lorentzian–60% Gaussian). The line profile measurements and PS analysis presented in this work provide new insight into the heterogeneous distribution of elastic strains in crystals undergoing elastic–plastic deformation during shock compression. Such microstrain distribution measurements are complementary to continuum measurements, which represent averages of the heterogeneous strains or stresses. The PS analysis is a general method capable of incorporating microstructural models more complex than the microstrain distribution model used in this work. As a next step, the PS method will be applied to line profiles of multiple diffraction peaks to separate strain- and size-broadening effects in shocked crystals.

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Scardi, Paolo, Cristy L. Azanza Ricardo, Camilo Perez-Demydenko et Alan A. Coelho. « Whole powder pattern modelling macros for TOPAS ». Journal of Applied Crystallography 51, n^o 6 (18 octobre 2018) : 1752–65. http://dx.doi.org/10.1107/s160057671801289x.

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Macros implementing the main concepts of the whole powder pattern modelling approach have been written for TOPAS. Size and strain broadening components of the diffraction line profiles can be convolved with the instrumental profile already available among the standard commands of TOPAS. Specific macros are presented with examples of applications including plastically deformed powders and atomistic simulations. A macro is presented for the modelling of surface relaxation effects in spherical nanocrystals.

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