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Beersheba, Israel

Auslender M.,Israel Electric | Felner I.,Hebrew University of Jerusalem | Mogilyansky D.,Institute of Applied Research | Mukovskii Ya.M.,Moscow Institute of Steel And Alloys
Journal of Applied Physics | Year: 2011

Magnetic properties, electron paramagnetic and ferromagnetic resonance were studied in the vicinity and above ferromagnetic-paramagnetic (FM-PM) phase transition of the La0.9Sr0.1MnO3 crystal. It appears that complex chemical/structural disorder inherent to manganites influences strongly on both magnetic and resonance properties of this crystal. In particular, it changes the nature of a FM-PM transition to the first- or mixed-order one and induces FM clustering in their PM state. The latter effect results in coexistence of resonance signals, and non-linearity of the PM inverse magnetic susceptibility versus temperature. This model seems to be much more realistic for description of the PM state in La0.9Sr 0.1MnO3 than an idealized Griffiths phase approach. © 2011 American Institute of Physics. Source

Auslender M.,Israel Electric | Felner I.,Hebrew University of Jerusalem | Mogilyansky D.,Institute of Applied Research | Pestun A.,Moscow Institute of Steel And Alloys | Mukovskii Y.M.,Moscow Institute of Steel And Alloys
Journal of Applied Physics | Year: 2011

The X-band electron paramagnetic resonance (EPR) was studied in the electron-doped ceramic La0.3Ca0.7MnO3. The model fittings of measured temperature dependences of the EPR linewidth and intensity were employed to probe the paramagnetic spin correlations and spin dynamics. These fittings revealed notable ferromagnetic short-range correlations and pure ion-ion spin relaxation in the paramagnetic state of La 0.3Ca0.7MnO3. The latter fact supports the local nature of ferromagnetic double exchange coupling in this very case. It is suggested that such character of ferromagnetic exchange interactions results in the localization of carriers and establishing of charge ordered antiferromagnetic insulating ground state. This finding may be considered a strong prerequisite for the electron-hole doping asymmetry observed in the phase diagram of La-Ca manganites. © 2011 American Institute of Physics. Source

Liaugaudas G.,Institute of Applied Research | Jarasiunas K.,Institute of Applied Research | Tsavdaris N.,Grenoble Institute of Technology | Sarigiannidou E.,Grenoble Institute of Technology | Chaussende D.,Grenoble Institute of Technology
Materials Science Forum | Year: 2015

Investigation of excess carrier dynamics in a 15R-SiC bulk layer grown by physical vapour transport (PVT) on 15R-SiC substrate has been carried out using “pump-probe” techniques: an interband carrier injection by a picosecond laser pulse and measuring the induced absorption and diffraction of a probe beam. For this task, differential transmittivity (DT) and light induced transient grating (LITG) techniques were used. Room temperature carrier lifetime varied in the 3 ns - 8 ns range at excess carrier densities above ∆No = 7×1017 cm-3 and was ascribed to the recovery time of optically recharged carrier traps, and their activation energy of Ea = 75 meV was determined. The presence of recharged traps caused the injection-dependence of the diffusion coefficient D, whereby its value dropped below 0.1 cm2/s at ∆No <1×1018 cm-3 and gradually increased up to 0.7 cm2/s at higher injections. At elevated temperatures (300 K < T < 700 K), when the traps are thermally activated, the diffusivity increased up to ~ 1.5 cm2/s and was independent on ∆ No). The overgrown layer parameters were comparable to those of the used 15R PVT seed. © (2015) Trans Tech Publications, Switzerland. Source

Yousef M.,Institute of Applied Research | Allmer J.,Izmir Institute of Technology | Allmer J.,Bionia Incorporated | Khalifa W.,Institute of Applied Research
BIOINFORMATICS 2016 - 7th International Conference on Bioinformatics Models, Methods and Algorithms, Proceedings; Part of 9th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2016 | Year: 2016

Traditionally, machine learning algorithms build classification models from positive and negative examples. Recently, one-class classification (OCC) receives increasing attention in machine learning for problems where the negative class cannot be defined unambiguously. This is specifically problematic in bioinformatics since for some important biological problems the target class (positive class) is easy to obtain while the negative one cannot be measured. Artificially generating the negative class data can be based on unreliable assumptions. Several studies have applied two-class machine learning to predict microRNAs (miRNAs) and their target. Different approaches for the generation of an artificial negative class have been applied, but may lead to a biased performance estimate. Feature selection has been well studied for the two-class classification problem, while fewer methods are available for feature selection in respect to OCC. In this study, we present a feature selection approach for applying one-class classification to the prediction of miRNA targets. A comparison between one-class and two-class approaches is presented to highlight that their performance are similar while one-class classification is not based on questionable artificial data for training and performance evaluation. We further show that the feature selection method we tried works to a degree, but needs improvement in the future. Perhaps it could be combined with other approaches. Copyright © 2016 by SCITEPRESS - Science and Technology Publications, Lda. All rights reserved. Source

Loman L.A.,Institute of Applied Research | Siegel G.L.,Institute of Applied Research
Child Abuse and Neglect | Year: 2015

An outcome analysis was conducted based on an extended follow-up of the implementation of differential response program reforms in Child Protective Services offices in 10 counties in a Midwestern U.S. State. Random assignment was conducted of families that were first determined to be appropriate for family assessments. Experimental families (n = 2,382) were each assigned to a non-forensic family assessment, and control families (n = 2,247) each received a forensic investigation. Families were assigned continuously over a 15-month period and then tracked from 45 to 60 months from the date of assignment. Detailed information on services provided and family responses was obtained via two subsamples of experimental and control families. Measures of family engagement and service reception and utilization were utilized to determine instrumental outcomes introduced through family assessments. Improved family engagement and increased and broadened services were found to have occurred, and it was theorized that these changes mediated extended outcomes. Extended outcomes included reductions of rates of subsequent screened-in reports of child maltreatment, proportions of families that experienced child removals, and instances of new safety threats and problems in parenting. Differences in outcomes were found among the participating counties with 4 counties accounting for most outcome differences. The relationships between instrumental and extended outcomes were discussed with suggestions for further research. © 2014 The Authors. Source

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