Shahid Beheshti University of Medical Sciences and Health Services

About: Shahid Beheshti University of Medical Sciences and Health Services is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Population & Medicine. The organization has 19456 authors who have published 33659 publications receiving 365676 citations.

Five-year results of vital pulp therapy in permanent molars with irreversible pulpitis: a non-inferiority multicenter randomized clinical trial

Abstract: Objectives Previous reported results of up to 12 months as well as 24-month follow-ups revealed superior and equivalent treatment outcomes for vital pulp therapy (VPT) using calcium-enriched mixture cement (CEM) in comparison with root canal therapy (RCT) for mature molars with established irreversible pulpitis, respectively. Present non-inferiority multicenter randomized clinical trial assesses the final long-term (5-year) results as well as the effects of patients’ age/gender and the presence of preoperative periapical lesion on the treatment outcomes.

Regression convolutional neural network for improved simultaneous EMG control.

Abstract: OBJECTIVE Deep learning models can learn representations of data that extract useful information in order to perform prediction without feature engineering. In this paper, an electromyography (EMG) control scheme with a regression convolutional neural network (CNN) is proposed as a substitute of conventional regression models that use purposefully designed features. APPROACH The usability of the regression CNN model is validated for the first time, using an online Fitts' law style test with both individual and simultaneous wrist motions. Results were compared to that of a support vector regression-based scheme with a group of widely used extracted features. MAIN RESULTS In spite of the proven efficiency of these well-known features, the CNN-based system outperformed the support vector machine (SVM) based scheme in throughput, due to higher regression accuracies especially with high EMG amplitudes. SIGNIFICANCE These results indicate that the CNN model can extract underlying motor control information from EMG signals during single and multiple degree-of-freedom (DoF) tasks. The advantage of regression CNN over classification CNN (studied previously) is that it allows independent and simultaneous control of motions.

Effect of Nanochitosan-Based Coating With and Without Copper Loaded on Physicochemical and Bioactive Components of Fresh Strawberry Fruit (Fragaria x ananassa Duchesne) During Storage

Abstract: Edible coatings based on nanochitosan (50–110 nm) with and without copper loaded were evaluated on physicochemical and bioactive components of strawberry. Fresh fruits were coated with copper-free and copper-loaded nanochitosans and stored at 4 ± 1 °C with 70 % relative humidity for 20 days. Both nanochitosan coatings provided an effective control in reducing weight loss and firmness as well as delayed changes in the respiration rate during 3 weeks. The antioxidant activity declined throughout the storage period of strawberries, although the decrease in antioxidant activity showed a slower rate in the strawberries coated with copper-free nanochitosan followed by copper-loaded nanochitosan compared with the control. Anthocyanin concentrations increased in fruits coated with copper free as well as copper-loaded nonochitosan at the first 12 days of storage followed by reduction in slow rates. However, no increase of anthocyanin was recorded for uncoated samples. Intensive reduction was recorded in ascorbic acid content of strawberries coated with copper-loaded nanochitosan, while the minimum loss of the ascorbic acid content was related to the copper-free nanochitosan. Also, both nanochitosans showed a significant suppression on the polyphenol oxidase and peroxidase activity, whereas a high rate of increase was recorded in control strawberry. The nanochitosan coatings with or without copper loaded significantly suppressed the visual loss and fungal decay of the strawberries during the storage compared with the control. The sensory evaluation of coated strawberries revealed that no effect on the consumer acceptability was detected as well as that copper-free nanochitosan showed better results in the point of preserving the overall flavor and appearance compared with the copper-loaded one.

Wound dressing application of pH-sensitive carbon dots/chitosan hydrogel

Abstract: Monitoring the pH of wounds has been recognized as an essential diagnosis factor during the healing process. This study presents a novel chitosan–carbon dots nanocomposite with dual applications as an antibacterial and pH-sensitive nano-agent for enhancing wound healing and monitoring the pH at the same time. The carbon dots (CDs) were synthesized using ammonium hydrogen citrate under hydrothermal conditions. The chitosan-based nanocomposites with different concentrations of CDs were fabricated through a solvent casting method. After detailed material characterization of the CDs and chitosan/CDs nanocomposites, the antibacterial activities and cell viability were thoroughly investigated against the Staphylococcus aureus bacterial species and L929 fibroblastic cell lines, respectively. The results indicated that the chitosan/CDs nanocomposites were biocompatible and nontoxic with effective antibacterial properties. The mechanical properties of the chitosan/CDs nanocomposite were improved via the addition of the CDs. The results show that the preparation of the chitosan/CDs nanocomposite at a concentration of 1.0 wt% carbon dots possessed the best optical, biological and mechanical characteristics. Furthermore, the results reveal that the proposed chitosan/CDs nanocomposites had outstanding pH-sensitive properties. According to the strong antibacterial properties and nontoxicity, as well as outstanding pH-sensitive nature, the proposed chitosan/CDs nanocomposites, as a smart materiel, have great potential applications in tissue engineering. Furthermore, the optimized ratio of CDs/chitosan nanocomposite was used as an antibacterial wound healing bandage and in vivo experiments were carried out on three groups of rats. The results showed that the CDs/chitosan nanocomposite not only possessed high pH sensitivity, but could also improve the wound healing process due to its antibacterial properties.