Psychometric properties of the Arabic version of the everyday memory questionnaire - revised (EMQ-R) among the Lebanese population.

Objective: This study aimed to evaluate the psychometric properties of the Arabic version of the Everyday Memory Questionnaire- Revised (EMQ-R-A) in a sample of Lebanese adults. Methods: A cross-sectional study was conducted in August 2023. A diverse sample of 483 Lebanese adults aged 18 to 60 years from all Lebanese governorates was recruited. Participants completed an Arabic-language questionnaire comprising three sections: socio-demographic characteristics, health-related inquiries, the EMQ-R-A and the Arabic version of the Prospective and Retrospective Memory Questionnaire (PRMQ). Results: The study's findings indicated that the EMQ-R-A displayed strong internal consistency (Cronbach's alpha = 0.925). Convergent validity was supported by a significant correlation with PRMQ. Test-retest results demonstrated strong reliability with a Cronbach's alpha of 0.925. Confirmatory factor analysis revealed a three-factor model including retrieval related factors, attentional tracking related factors, and other factors. The factors labeled "Retrieval" and "Attentional Tracking" elucidate aspects of memory retrieval system efficacy and attention-related challenges. Higher EMQ-R-A scores were found to be associated with the female gender, lower attention, physical inactivity, lower educational levels, and higher number of comorbid disorders. Conclusion: The EMQ-R-A exhibits good validity and reliability. The identified factors associated with memory decline underscore the importance of addressing lifestyle factors, such as promoting physical activity, better educational attainment, and addressing comorbid health conditions, to potentially mitigate memory challenges.

Self-Calibrated Laser-Induced Breakdown Spectroscopy for the Quantitative Elemental Analysis of Suspended Volcanic Ash.

Real-time analysis of fine ash in volcanic plumes, which represent magma fragments expelled from the crater during explosive eruptions, is a valuable tool for volcano monitoring and hazard assessment. To obtain the chemical characterization of the juvenile pyroclastic material emitted in volcanic plumes, many analytical techniques can be used. Among them, laser-induced breakdown spectroscopy (LIBS) is the one that can most easily be adapted to advanced applications in extreme environments. In this paper, LIBS experiments based on self-calibrated approaches are used to determine the elemental composition of suspended volcanic ash. To simulate the conditions of dispersed volcanic ash in the atmosphere, different sizes of volcanic ash samples are suspended in the air by laser-induced shockwaves in a dedicated chamber, and a parametric study is carried out to establish the optimal experimental conditions for recording usable plasma emission spectra for each ash size. The quantitative analysis is performed using a self-calibrated analytical method, including calibration-free LIBS, which is based on the calculation of the spectral radiance of a uniform plasma in local thermodynamic equilibrium. The method accounts intrinsically for self-absorption since it modifies the intensity of spectral lines and thus leads to an underestimation of the elemental fraction. An intensity calibration of the spectra based on the measurements of Fe lines intensities was also used in this work to deduce the apparatus response from the spectrum itself and avoid the use of standard calibration lamps. Results demonstrate the potential of real-time measurements of elemental fractions in volcanic ash with good agreement with the literature composition.

Measurement error due to self-absorption in calibration-free laser-induced breakdown spectroscopy.

Self-absorption of spectral lines is known to lower the performance of analytical measurements via calibration-free laser-induced breakdown spectroscopy. However, the error growth due to this effect is not clearly assessed. Here we propose a method to quantify the measurement error due to self-absorption based on the calculation of the spectral radiance of a plasma in local thermodynamic equilibrium. Validated through spectroscopic measurements for a binary alloy thin film of compositional gradient, the method evidences that measurement performance lowering due to self-absorption depends on the spectral shape of the analytical transition and on the intensity measurement method. Thus, line-integrated intensity measurements of Stark broadened lines enable accurate analysis, even at large optical thickness, if line width and plasma size are precisely known. The error growth due to self-absorption is significantly larger for line shapes dominated by Doppler broadening and for line-center intensity measurements. The findings present a significant advance in compositional measurements via calibration-free laser-induced breakdown spectroscopy, as they enable straightforward selection of most appropriate analytical lines.