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Copyright of Al Bashaer Economic Journal is the property of Al Bashaer Economic Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aims to explore the impact of the Covid-19 pandemic on the components of the international tourism (the international tourists arrivals, the international tourists receipts, Hospitality and restaurants, The employment in tourism.); to achieve this purpose, we divide the paper into two axes, the first is devoted to the literature review of the issue, while the second is devoted to studying a set of studies and statistics issued by a group of the international reports. Finally, the initial results at the beginning of this pandemic indicate a decrease in the international flows of tourists by about 30% in the first semester of 2020 relative to 2019 as a result of the quarantine, which will negatively affect all components of the international tourism sector.

The development of advanced metal-oxide-semiconductor sensing technologies for the detection of Volatile Organic Compounds (VOCs) present in exhaled breath is of great importance for non-invasive, cheap and fast medical diagnostics. Our experimental studies investigate the effects of operating temperature selection and UV-light irradiation on improving the response of WO 3 nanowire sensors towards exhaled breath exposure. Herein, six WO 3 nanowire sensors (both pristine and doped with a range of metal nanoparticles such as Pt, Au, Au/Pt, Ni and Fe) were synthesised via Aerosol-Assisted Chemical Vapour Deposition (AACVD) and characterized by means of Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray (EDX-ray). Breath measurements were performed in the dark and under UV-light irradiation at various sensor operating temperatures. The results demonstrate that UV-light irradiation combined with the optimisation of the sensors’ operating temperature can greatly enhance the sensors’ responses towards breath exposure. [ABSTRACT FROM AUTHOR]

Urinary creatinine content (UCC) has been investigated as a promising approach for health states monitoring. Most of the techniques used for UCC detection are non-portable and require dilution with other reagents. This study aims to investigate the ability of a Voltammetric Electronic tongue (VE-tongue) combined with chemometrics to discriminate and identify UCC patterns of 59 volunteers without any dilution. The UCC measured by VE-tongue system were related with those found by Jaffe’s reaction as a reference method. Loading analysis was carried out to examine the electrodes and features contribution. Principal Component Analysis (PCA) and Support Vector Machines (SVMs) were implemented to analyze VE-tongue data. Furthermore, Partial Least Squares-regression (PLS-regression) was trained to correlate VE-tongue data with the reference measurement in order to build and validate a prediction model for UCC determination. The obtained results demonstrate that PCA and SVMs could classified urine samples into three classes according to low, medium and high creatinine levels (CLs). Promising findings were also obtained in the identification of a new measurement set. Moreover, high correlation coefficients were obtained between the electrochemical technique and spectroscopic Jaffe’s method using PLS-regression. This demonstrates a well promising tool for simple alternative process for UCC determination without dilution. [ABSTRACT FROM AUTHOR]

Adulteration detection of argan oil is one of themain aspects of its quality control. Following recent fraud scandals, it ismandatory to ensure product quality and customer protection. The aim of this study is to detect the percentages of adulteration of argan oil with sunflower oil by using the combination of a voltammetric e-tongue and an e-nose based on metal oxide semiconductor sensors and pattern recognition techniques. Data analysis is performed by three pattern recognition methods: principal component analysis (PCA), discriminant factor analysis (DFA), and support vector machines (SVMs). Excellent results were obtained in the differentiation between unadulterated and adulterated argan oil with sunflower one. To the best of our knowledge, this is the first attempt to demonstrate whether the combined e-nose and e-tongue technologies could be successfully applied to the detection of adulteration of argan oil. [ABSTRACT FROM AUTHOR]

Here we present a proof-of-concept study showing the potential of a chemical gas sensors system to identify the patients with alveolar echinococcosis disease through exhaled breath analysis. The sensors system employed comprised an array of three commercial gas sensors and a custom gas sensor based on WO3 nanowires doped with gold nanoparticles, optimized for the measurement of common breath volatile organic compounds. The measurement setup was designed for the concomitant measurement of both sensors DC resistance and AC fluctuations during breath samples exposure. Discriminant Function Analysis classification models were built with features extracted from sensors responses, and the discrimination of alveolar echinococcosis was estimated through bootstrap validation. The commercial sensor that detects gases such as alkane derivatives and ethanol, associated with lipid peroxidation and intestinal gut flora, provided the best classification (63.4% success rate, 66.3% sensitivity and 54.6% specificity) when sensors' responses were individually analyzed, while the model built with the AC features extracted from the responses of the cross-reactive sensors array yielded 90.2% classification success rate, 93.6% sensitivity and 79.4% specificity. This result paves the way for the development of a noninvasive, easy to use, fast and inexpensive diagnostic test for alveolar echinococcosis diagnosis at an early stage, when curative treatment can be applied to the patients. [ABSTRACT FROM AUTHOR]