In collaborative clinical learning field, several recent pertinent studies showed that gathering learners with their tutor still insufficient to improve students' learning quality and knowledge acquisition. Consequently, focusing attention on professional skills within a collaboration environment seems to be the most appropriate way to reach the wished learning objectives, particularly in a complex specialty such as medical diagnosis learning. In this paper, we firstly introduce the concept of medical diagnosis from cognitive studies view that have been performed in the field of medical education. Then, we will discuss our shared web environment designed to support distance diagnosis learning, which aims to promote knowledge coconstruction and collaboration between learner

Context: This is the first study on the phytochemistry, antioxidant, anticholinesterase, and antibacterial activities of Sedum caeruleum L. (Crassulaceae). Objective: The objective of this study is to isolate the secondary metabolites and determine the antioxidant, anticholinesterase, and antibacterial activities of S. caeruleum. Materials and methods: Six compounds (1–6) were isolated from the extracts of S. caeruleum and elucidated using UV, 1D-, 2D-NMR, and MS techniques. Antioxidant activity was investigated using DPPH•, CUPRAC, and ferrous-ions chelating assays. Anticholinesterase activity was determined against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes using the Ellman method. Antibacterial activity was performed according to disc diffusion and minimum inhibitory concentration (MIC) methods. Results: Isolated compounds were elucidated as ursolic acid (1), daucosterol (2), β-sitosterol-3-O-β-d-galactopyranoside (3), apigenin (4), apigetrin (5), and apiin (6). The butanol extract exhibited highest antioxidant activity in all tests (IC50 value: 28.35 ± 1.22 µg/mL in DPPH assay, IC50 value: 40.83 ± 2.24 µg/L in metal chelating activity, and IC50value: 23.52 ± 0.44 µg/L in CUPRAC), and the highest BChE inhibitory activity (IC50 value: 36.89 ± 0.15 µg/L). Moreover, the chloroform extract mildly inhibited (MIC value: 80 µg/mL) the growth of all the tested bacterial strains. Discussion and conclusion: Ursolic acid (1), daucosterol (2), β-sitosterol-3-O-β-d-galactopyranoside (3), apigenin (4), apigetrin (5), and apiin (6) were isolated from Sedum caeruleum for the first time. In addition, a correlation was observed between antioxidant and anticholinesterase activities of bioactive ingredients of this plant.

This article deals with the study of a new swimming microrobot behavior using an analytical investigation. The analyzed microrobot is associated by a spherical head and hybrid tail. The principle of modeling is based on solving of the coupled elastic/fluidic problems between the hybrid tail’s deflections and the running environment. In spite of the resulting nonlinear model can be exploited to enhance both the sailing ability and also can be controlled in viscous environment using nonlinear control investigations. The applications of the micro-robot have required the precision of control for targeting the running area in terms of response time and tracking error. Due to these limitations, the Flatness-ANFIS based control is used to ensure a good control behavior in hazardous environment. Our control investigation is coupled the differential flatness and adaptive neuro-fuzzy inference techniques, in which the flatness is used to planning the optimal trajectory and eliminate the nonlinearity effects of the resulting model. In other hand, the neuro-fuzzy inference technique is used to build the law of control technique and minimize the dynamic error of tracking trajectory. In particular, we deduct from a non linear model to an optimal model of the design parameter’s using Multi-Objective genetic algorithms (MOGAs). In addition, Computational fluid dynamics modeling of the microrobot is also carried out to study the produced thrust and velocity of the microrobot displacement taking into account the fluid parameters. Our analytical results have been validated by the recorded good agreement between the numerical and analytical results.