The inhibiting effect of chloroquine compounds (ChCs) on the SARS-CoV-2 virus represents a highly debated form of study owing to the emerging proposals of mechanistic implications for exploring the mode of action of ChCs on the virus. Keeping in view the emerging significance of chloroquine derivatives, the present study was performed to screen one hundred and ninety known chloroquine derivatives for their interaction with several SARS-CoV-2 target proteins by molecular docking and molecular dynamics simulations to obtain an in-depth understanding of the potential hits of these compounds against SARS-CoV-2. A total of 190 molecules from the chloroquine family were screened for the identification of potential new inhibitors of the three therapeutic target proteins of SARS-CoV-2, namely Mpro (master protease), PLpro (papain-like protease) and SGp-RBD (spike glycoprotein receptor binding domain). The ChCs bound to SARS-COV-2 Mpro, PLpro, and SGp-RBD were generated by molecular docking and molecular dynamics simulations. Herein, a comparative analysis of chloroquine family products and a well-known drug against SARS-CoV-2, called Remdesivir, has also been presented. This investigation is intended to study the mechanism of interaction between ChCs and the SARS-CoV-2 virus and explore the unprecedented areas associated with the inhibitory activity of ChCs against this virus.

The paradigm of the cyber-physical manufacturing system is playing an increasingly important role in the development of production systems and management of manufacturing processes. This paper presents an optimization model for solving an integrated problem of production planning and manufacturing control. The goal is to create detailed production plans for a complex manufacturing system and to control the skilled manual workers. The detailed optimization model of the problem and the developed approach and algorithms are described in detail. To consider the impact of human workers performing the manufacturing primary operations, we elaborated an extended simulation-based procedure and new multi-criteria control algorithms that can manage varying availability constraints of parallel workstations, worker-dependent processing times, different product types and process plans. The effectiveness of the proposed algorithms is demonstrated by numerical results based on a case study.

For understanding the place of income in smartphone diffusion, this paper aims to find out the dependence of smartphone market indicators on income level worldwide and in the developing economies. The strength of the relationship between above mentioned variables identifies the speed of smartphone diffusion influenced by income. For current purposes, secondary data from 189 countries were analyzed by using Hierarchical Cluster Analysis and Chi-square analysis. The results confirmed that income level influences smartphone purchase and diffusion. However, the strength of the relationship between income and smartphone market indicators is diverse globally and in developing countries. In developing countries, the strength of the relationship is smaller in comparison with the overall results. It means that income level has weak moderating effect in smartphone diffusion, and it cannot be considered as a key indicator of smartphone diffusion in developing countries according to results of the analysis in 2016 and the arithmetic mean of 2013-2017 years.

Internal auditors are considered a valuable source of information since they are more familiar with the company and its environment. This study aimed to identify the relationship between internal and external audits affecting the quality of firms' reports. To achieve the objectives of the study, a 30-item questionnaire was developed and sent to 312 external auditors and managed to collect 276 (88.5%) properly filled questionnaires. Descriptive statistics and multiple regression were used to test the hypotheses of the study. The results show that Jordanian auditors perceived favorably the cooperation between internal and external auditors to enhance the quality of financial reporting. For instance, the results revealed positive and significant effect of objectivity in enhancing the level of cooperation between internal and external auditors in a way that increased the level of financial reporting quality. Moreover, the quality of financial reporting has been affected positively resulting in the positive effect of the technical competence of the internal audit’s work and professional care. Finally, the cooperation between the two auditing teams was noticeable through the nature and scope dimension that, in turn, increased the quality of financial reporting. Based on these results, external auditors are highly recommended to rely on internal audit works which could lead to enhance financial reporting quality.

Failure of composite materials due to poor anticipations of damages occur very frequently. Damages in composite materials may exist as visible or non-visible with different configurations and identities. Thus, investigation of damages existence in composite materials has to have prior attention to avoid the failure of structures. The current work investigates the damping response offered by a damaged fiber-reinforced polymer plate. The plate is put under three different conditions regarding the damage existence. The focus is to measure the loss factor in all cases and determine whether there is a difference among them to prove damage presence in the composite part. The loss factor is experimentally measured by measuring the reverberation time RT60. The resulting data of loss factors show a well-distinguished difference that might lead to predicted damages and to do a more expanded analysis of this issue.

This work is a contribution to the study of the rigidity of rotational friction welding of cylindrical specimens made on a parallel lathe. We performed welding of three combinations of parts: steel / steel, aluminium / aluminium and steel / aluminium according to three numbers of rotations of the spindle (900, 1250 and 1800 rpm). To control the rigidity and quality of these assemblies, tensile tests are used followed by ultrasonic testing to ensure that the tips are welded and that there are no internal defects. Hardness profile of the welded zone according to the welding parameters was obtained. Metallographic observations have detected the profile of the various zones welded and affected thermally. The results of the mechanical tests showed that a rotation speed of 1250 rpm can produce a very good weld, with other parameters kept constant.