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Wearable robots are robots which are used for rehabilitation or augmentation by human. Recently, there has been an increasing interest in the development of wearable devices to assist elderly as well as patients, soldiers and many other persons for movement assistance and power augmentation. On the other hand, a realization of wearable robot which has the same degree of freedom of a human is not easy from considerations about a size and weight of device. This study is about a lower limb assist robot that consist of just an actuator on each of legs. In this paper after a brief review on wearable robots and their applications, a suitable design of robot which is named RoboWalk presented with inspiring from Honda weight compensation system. In the following kinematics and dynamics modeling of system presents with using of denavit-hartenberg parameters and validates with ADAMS software results. Results with high accuracy has been achieved. It’s necessary to evaluate main foundation of design of robot which is an assistant force in the direction of foot reaction force that has been achieved with the accuracy of 0.02 radians. finally effect of change in user’s weight, position of center of mass and friction of walking assistant robot component is examined in this study.

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Trying to treat COVID-19 patients has caused serious problems for the scientists. There are many routinely used drugs in clinical settings without definite effects, and more studies should be done so as to reach a successful treatment for COVID-19. Our aim is to evaluate four suggested chemicals using virtual analysis tools based on the drug-screening approach and application of cheminformatics, pharmacotoxicology and docking.
Four repurposed drugs: rizatriptan, dasabuvir, pravastatin, and empagliflozin are used in the study. The 3D structure of COVID-19 Main Protease (M Pro) was obtained from protein data bank (PDB) with PDB code: 6LU7, as the target of binding site screening. Besides, cheminformatics, pharmacotoxicology and human proteins targets for each drug was evaluated using SwissADME interface, SwissTarget Prediction web server, toxicity estimation software tool (T.E.S.T) and Toxtree-v3.1.0.1851 offline software.
The docking scores (DOS) were -139.399, -125.707, -102.183 and -99.6642 for dasabuvir, rizatriptan, empagliflozin and pravastatin, respectively. In addition, the quantitative structure-activity relationship (QSAR) and pharmacotoxicologic evaluations show dasabuvir has more acceptable results than the others. Human protein target-exploration show that rizatriptan interacts with G protein-coupled receptor and kinase enzymes, pravastatin targets the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, while empagliflozin interacts with sodium/glucose cotransporters (SLC). But, dasabuvir targets human protein with too low scores.
Virtual screening applied to four potential anti-COVID-19 drugs shows that dasabuvir may be a safer and efficient agent, regarding pharmacotoxicology and therapeutic purposes. However, virtually screened agent/s should be evaluated by experimental models for ultimate confirmation.