The Experts below are selected from a list of 78510 Experts worldwide ranked by ideXlab platform
Antonio Martellucci - One of the best experts on this subject based on the ideXlab platform.
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modeling and predicting sky noise temperature of clear cloudy and rainy atmosphere from x to w band
IEEE Transactions on Antennas and Propagation, 2013Co-Authors: V Mattioli, F S Marzano, Nazzareno Pierdicca, C Capsoni, Antonio MartellucciAbstract:A physically-based parametric model (PPM) to predict the sky-noise temperature in all weather conditions is proposed. The proposed prediction model is based on the non-linear Regression Fit of numerical simulations derived from the sky-noise eddington radiative-transfer model (SNEM) in an absorbing and scattering medium such as gaseous, cloudy and rainy atmosphere. The PPM prediction method, dependent on measured path attenuation, beacon frequency, and antenna-pointing elevation angle, describes the statistical behavior of the atmospheric mean radiative temperature, which in its turn relates sky-noise temperature to slant-path attenuation. PPM validity ranges from X-to W- band and from 10 to 90 in terms of elevation angle. A comparison of the estimated PPM radio-propagation variables with corresponding ITALSAT satellite data, collected at the Spino d'Adda receiving station (Italy), is also carried out and discussed. The PPM prediction technique provides a root-mean-square retrieval error generally less than 8 K for all frequencies. Results show an improvement with respect to the current International Telecommunication Union (ITU) recommendations, especially at Q- and V-band and above, where the atmospheric multiple scattering effects cannot be disregarded.
R Benabou - One of the best experts on this subject based on the ideXlab platform.
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1119 Superior Test-Retest Reliability of a Computerized Cognitive Assessment vs SLUMS During an 18-Month Longitudinal Study
Sleep, 2020Co-Authors: J C Andrefsky, Diego Cahn-hidalgo, R BenabouAbstract:Abstract Introduction Chronic sleep deprivation has been associated with cognitive impairment (CI) in multiple studies. Cognivue is an FDA-cleared computerized testing tool that provides adaptive psychophysic evaluation of cognitive functions (CF). A reliable objective method to evaluate CF in patients with sleep disorders could be helpful to optimize long-term treatment. In an FDA clearance study, Cognivue demonstrated good agreement with St. Louis University Mental Status (SLUMS) and other neuropsychological tests, and superior test re-test reliability compared to SLUMS across 2 sessions, 1 to 2 weeks apart (Cognivue Regression Fit: R2= 0.81, r= 0.90); SLUMS Regression Fit: R2 = 0.67, r= 0.82). Methods 238 subjects from the FDA clearance study enrolled in the longitudinal study. They underwent Cognivue test and SLUMS at 3 sessions over 18 months (6, 12, 18 months post-FDA study). An analysis of rank linear Regression test-retest reliability was performed for both tests. Results Among these 238 patients, Cognivue demonstrated similar linear Regression scores across comparisons (test session 1&2: Regression Fit: R2= 0.76; r = 0.87; test session 1&3: Regression Fit: R2= 0.72; r = 0.85; test session 1&4: Regression Fit: R2= 0.73; r = 0.86). The SLUMS test demonstrated greater variability in Regression scores across test sessions (test session 1&2: Regression Fit: R2= 0.63; r = 0.79; test session 1&3: Regression Fit: R2= 0.43 r = 0.65; test session 1&4: Regression Fit: R2= 0.64; r = 0.80). Conclusion Cognivue demonstrated maintained superior test re-test reliability compared to SLUMS over a period of 18 months after the FDA clearance study. With that, Cognivue could be beneficial in detecting early stages of multi-domain CI in patients with sleep disorders, providing an opportunity for early intervention strategies and follow-up over time to improve patient outcomes. Support Cognivue, Inc.
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SUPERIOR TEST-RETEST RELIABILITY OF COGNITIVE ASSESSMENT WITH COGNIVUE® VS SLUMS DURING AN 18-MONTH LONGITUDINAL STUDY
The American Journal of Geriatric Psychiatry, 2020Co-Authors: J C Andrefsky, Diego Cahn-hidalgo, R BenabouAbstract:Introduction Cognivue is an FDA-cleared computerized testing tool designed to assess early signs of cognitive impairment. In an FDA clearance study, Cognivue demonstrated good agreement with St. Louis University Mental Status (SLUMS) and other neuropsychological tests, and superior test re-test reliability compared to SLUMS across 2 sessions, 1 to 2 weeks apart (Cognivue Regression Fit: R2= 0.81, r= 0.90); SLUMS Regression Fit: R2 = 0.67, r= 0.82). Further follow up long-term data analysis within this cohort was done to study Cognivue's test re-test reliability vs SLUMS over time. Methods 238 subjects from the FDA clearance study enrolled in the longitudinal study. They underwent the Cognivue test and SLUMS at 3 sessions over the course of 18 months (6, 12, 18 months post-FDA study). An analysis of rank linear Regression test-retest reliability was performed for both tests. In a separate sub-analysis, the medical records of those subjects were analyzed to determine the correlation, if any, between comorbidities or medication usage and Cognivue score. Results Among these 238 patients, Cognivue demonstrated similar linear Regression scores across comparisons (test session 1&2: Regression Fit: R2= 0.76; r = 0.87; test session 1&3: Regression Fit: R2= 0.72; r = 0.85; test session 1&4: Regression Fit: R2= 0.73; r = 0.86). The SLUMS test demonstrated greater variability in Regression scores across test sessions (test session 1&2: Regression Fit: R2= 0.63; r = 0.79; test session 1&3: Regression Fit: R2= 0.43 r = 0.65; test session 1&4: Regression Fit: R2= 0.64; r = 0.80). In the subanalysis, medical records of 203 subjects were analyzed. Overall, an increased co-morbidity count significantly decreased subjects’ Cognivue scores (correlation -0.21; P=0.01). Cardiopulmonary comorbidities had the largest impact on a patient's Cognivue score (78.0 score for those without this comorbidity vs 67.1 score for those with; P Conclusions Cognivue demonstrated maintained superior test re-test reliability compared to SLUMS over a period of 18 months after the FDA clearance study. An increased comorbidity count and cardiopulmonary comorbidities significantly decreased a subject's Cognivue score over time. This research was funded by: Cognivue, Inc.
V Mattioli - One of the best experts on this subject based on the ideXlab platform.
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modeling and predicting sky noise temperature of clear cloudy and rainy atmosphere from x to w band
IEEE Transactions on Antennas and Propagation, 2013Co-Authors: V Mattioli, F S Marzano, Nazzareno Pierdicca, C Capsoni, Antonio MartellucciAbstract:A physically-based parametric model (PPM) to predict the sky-noise temperature in all weather conditions is proposed. The proposed prediction model is based on the non-linear Regression Fit of numerical simulations derived from the sky-noise eddington radiative-transfer model (SNEM) in an absorbing and scattering medium such as gaseous, cloudy and rainy atmosphere. The PPM prediction method, dependent on measured path attenuation, beacon frequency, and antenna-pointing elevation angle, describes the statistical behavior of the atmospheric mean radiative temperature, which in its turn relates sky-noise temperature to slant-path attenuation. PPM validity ranges from X-to W- band and from 10 to 90 in terms of elevation angle. A comparison of the estimated PPM radio-propagation variables with corresponding ITALSAT satellite data, collected at the Spino d'Adda receiving station (Italy), is also carried out and discussed. The PPM prediction technique provides a root-mean-square retrieval error generally less than 8 K for all frequencies. Results show an improvement with respect to the current International Telecommunication Union (ITU) recommendations, especially at Q- and V-band and above, where the atmospheric multiple scattering effects cannot be disregarded.
Harold F Farrell - One of the best experts on this subject based on the ideXlab platform.
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Reproducibility of the nonlinear Regression Fit to the FTIR spectra of lysozyme.
Talanta, 1997Co-Authors: Thomas F. Kumosinski, Joseph J. Unruh, Harold F FarrellAbstract:Abstract Controversy exists concerning the influence of experimental artifacts on the number of component FTIR vibrational bands which may be resolved from the amide I and II envelopes of proteins in water. Whether these bands represent unique populations of vibrating protein groups in a particular global 2° structure or whether the bands are due to instrumental and environmental fluctuations has been addressed, T.F. Kumosinski and J.J. Unruh, Talanta, 43 (1996) 199–219. The repeatability of the methodology and the apparent uniqueness of the nonlinear Regression Fits are addressed in this study. We obtained a series of the spectra of lysozyme, and carried-out nonlinear Regression analysis of each spectrum. Coefficients of variation (COV) were calculated for the wavenumber and area values of assigned component peaks obtained. Low COVs obtained attest to the precision of the methodology and the apparent uniqueness of the nonlinear Regression Fits. This methodology for acquisition and analysis of protein FTIR spectra yields results with good precision.
K. Ruebenbauer - One of the best experts on this subject based on the ideXlab platform.
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Calibration of the isomer shift for iodine resonant transitions by ab initio calculations.
Journal of Physical Chemistry A, 2010Co-Authors: U. D. Wdowik, Dominik Legut, K. RuebenbauerAbstract:The isomer shift calibration constants have been calculated for 57.60 keV in 127 I and for 27.72 kcV in 129 I resonant transitions by density functional theory. The full-potential linearized augmented plane-wave method (FLAPW) was applied in the scalar-relativistic approach. The NaI compound was used to set the origin of the scales in both cases. On the basis of the existing experimental data, the following values for the calibration constants were obtained: α =― 0.057(2) mm s ―1 au 3 for 127 I and α = +0.164(4) mm s ―1 au 3 for 129 I. The ratio of the calibration constants of α 127 /α 129 =— 0.35(1) was established. Spectroscopic electric quadrupole moments for the ground state of the above nuclei have been calculated as byproduct. The quadrupole moments Q (127) g = ―0.764(30) b and Q (129) g = ―0.731(3) b were obtained for 127 I and 129 I, respectively. Errors quoted are due to the linear Regression Fit, and real errors might be as large as about 10% of the quoted absolute value.
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Calibration of the isomer shift for the 77.34 keV transition in A197u using the full-potential linearized augmented plane-wave method
Journal of Chemical Physics, 2008Co-Authors: U. D. Wdowik, K. RuebenbauerAbstract:The isomer shift calibration constant has been calculated for the 77.34 keV Mossbauer transition connecting the ground state of the A197u nucleus with the first excited state of this nucleus. The full-potential linearized augmented plane-wave method was used in the fully relativistic approach, albeit without taking into account the spin-orbit coupling. The final assignment of the calibration constant was based on calculations performed for AuCN, AuCl3, AuBr3, KAuCl4, KAuBr4, and metallic gold. It is found that the calibration constant takes on the following value α=+0.0665(4) mm s−1 a.u.3. The error quoted is due to the linear Regression Fit, and the real error might be as large as 10%. The spectroscopic electric quadrupole moment for the ground state of the A197u nucleus was calculated as the by-product. It was found that this moment equals Qg=+0.566(1)b in fair agreement with the accepted value based on the muonic hyperfine spectroscopy results. The error quoted is again due to the linear Regression Fit...
