Sharif Digital Repository

Manganese Peroxidase (MnP), is one of the most promising lignin depolymerization enzymes, which has been widely used for degradation purposes. Nevertheless, MnP tends to lose activity rapidly during its maintenance phase and degradation process, especially in the inevitable presence of hydrogen peroxide. This study aimed to improve MnP efficiency produced by Phanerochaete chrysosporium, via enhancing its sustainability. In this context, the effects of MnO2, Fe3O4, PEG, Veratryl Alcohol (VA), and DMSO as stabilizing agents on MnP activity were explored both in vivo and in vitro. During in vivo experiments, heterogeneous Fe3O4 was found to be the desirable choice to enhance MnP production,... 

In this paper, LM pectin production from commercial apple pectin by using acid, alkali and ammonia methods in the presence of ethanol was studied. Also, the effect of different parameters such as, temperature, time, acid, alkali and ammonia treatment in LM pectin production were evaluated. In all the experiments, low temperature showed a better influence from a recovery, purity and low de-polymerization viewpoint. Optimum conditions in the acid method reached at pH = 2, t = 17 hrs and T = 30°C, in the alkaline method reached at pH = 11, t = 3 hrs and T = 5°C and in the ammonia method reached at 2 N ammonia and T = 5°C, were determined. © Sharif University of Technology  

In this study, a new model was developed to calculate gas pressure at the melt/foam interface due to foam degradation during mould filling in the lost foam casting process. Different aspects of the process, such as foam degradation, gas elimination, and permeability of the refractory coating, were incorporated into this model. A computational fluid dynamic code was developed based on the numerical technique of the solution algorithm-volume of fluid (SOLA-VOF) for the simulation and prediction of the melt flow. In order to verify the computational results of the simulation, a thin plate of grey iron at 1350 °C was poured into a transparent foam mould. The mould filling process was recorded... 

Alzheimer’s disease (AD) is an irreversible neurological disorder that progresses gradually and can cause severe cognitive and behavioral impairments. This disease is currently considered a social and economic incurable issue due to its complicated and multifactorial characteristics. Despite decades of extensive research, we still lack definitive AD diagnostic and effective therapeutic tools. Consequently, one of the most challenging subjects in modern medicine is the need for the development of new strategies for the treatment of AD. A large body of evidence indicates that amyloid-β (Aβ) peptide fibrillation plays a key role in the onset and progression of AD. Recent studies have reported... 

Background: Human amniotic membrane grafting could be potentially useful in ocular surface complications due to tissue similarity and the presence of factors that reduce inflammation, vascu-larization, and scarring. However, considerations like donor-derived infectious risk and the requirement of an invasive surgery limit the clinical application of such treatments. Moreover, the quick depletion of bioactive factors after grafting reduces the efficacy of treatments. Therefore, in the current study, the possibility of nano delivery of the bioactive factors extracted from the human amniotic membrane to the ocular surface was investigated. Materials and Methods: Nanoparticles were prepared...