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81.
Huynh Nguyen Simran Sangha Michelle Pan Dong Ha Shin Hayoung Park Ali I. Mohammed Nicola Cirillo 《International journal of molecular sciences》2022,23(9)
Chemoradiation-induced mucositis is a debilitating condition of the gastrointestinal tract eventuating from antineoplastic treatment. It is believed to occur primarily due to oxidative stress mechanisms, which generate Reactive Oxygen Species (ROS). The aim of this scoping review was to assess the role of oxidative stress in the development of Oral Mucositis (OM). Studies from the literature, published in MEDLINE and SCOPUS, that evaluated the oxidative stress pathways or antioxidant interventions for OM, were retrieved to elucidate the current understanding of their relationship. Studies failing inclusion criteria were excluded, and those suitable underwent data extraction, using a predefined data extraction table. Eighty-nine articles fulfilled criteria, and these were sub-stratified into models of study (in vitro, in vivo, or clinical) for evaluation. Thirty-five clinical studies evaluated antioxidant interventions on OM’s severity, duration, and pain, amongst other attributes. A number of clinical studies sought to elucidate the protective or therapeutic effects of compounds that had been pre-determined to have antioxidant properties, without directly assessing oxidative stress parameters (these were deemed “indirect evidence”). Forty-seven in vivo studies assessed the capacity of various compounds to prevent OM. Findings were mostly consistent, reporting reduced OM severity associated with a reduction in ROS, malondialdehyde (MDA), myeloperoxidase (MPO), but higher glutathione (GSH) and superoxide dismutase (SOD) activity or expression. Twenty-one in vitro studies assessed potential OM therapeutic interventions. The majority demonstrated successful a reduction in ROS, and in select studies, secondary molecules were assessed to identify the mechanism. In summary, this review highlighted numerous oxidative stress pathways involved in OM pathogenesis, which may inform the development of novel therapeutic targets. 相似文献
82.
Mohamed I. Ali A. Bayoumi Mostafa Adly A. Soliman 《Advanced Synthesis \u0026amp; Catalysis》1976,318(1):12-18
5-Aryl-3-carboxymethylthio-1,2,4-triazoles 2 are cyclised to 6-arylthiazolo[3,2-b]-s-triazol-3(2H)-ones 3 . This structural assignment has been based on IR and NMR spectra. 2-Arylmethylene-6-arylthiazolo[3,2-b]-s-triazol-3(2H)-ones 7 were prepared by several methods. Compounds 3 coupled with diazotised anilines to give 2,3-dihydro-6-arylthiazolo[3,2-b]-s-triazole-2,3-dione 2-arylhydrazones 8 . The action of amines on 3a opens the thiazolone ring with the formation of substituted (5-phenyltriazol-3-ylthio)-acetamides 9 . 相似文献
83.
Mohammed Ali Almomani Mohammed Aladeemy Abdelhakim Abdelhadi Ahmad Mumani 《Computers & Industrial Engineering》2013
Short setup time is an essential element for the effective implementation of many lean pillars, i.e., JIT, and Kanban. Most of the current setup reduction methodologies are based on Shingo’s Single Minute Exchange of Dies (SMED) that suggests the conversion of internal setup operations to external operations. However, the conventional SMED approach – as proposed by Shingo – does not possess a systematic approach to accomplish this conversion. Thus, a new approach is proposed in order to aid the process engineers in implementing SMED. The proposed approach is based on the conventional SMED, but also it incorporates Multiple Criteria Decision-Making Techniques (MCDM) to the third implementation phase. The MCDM techniques used in this work are Analytical Hierarchal Process (AHP), Preference Selection Index (PSI) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). The proposed approach provides a systematic procedure for selecting the best setup technique among the available alternatives, and takes also into consideration other factors that affect the decision-making process; including: cost, energy, facility layout, safety, life, quality and maintenance. A real example of PVC industry is used to exemplify the approach. The results demonstrate the capability of the proposed approach in setup time reduction, which in turn will improve machines’ utilization, and increase the productivity and flexibility of the whole facility. 相似文献
84.
In this paper, we introduce the notions of sum and direct sum of soft submodules, small soft submodules and radical of a soft module. Moreover, we obtain basic properties of such soft submodules. 相似文献
85.
We present a synchronized routing and scheduling problem that arises in the forest industry, as a variation of the log-truck scheduling problem. It combines routing and scheduling of trucks with specific constraints related to the Canadian forestry context. This problem includes aspects such as pick-up and delivery, multiple products, inventory stock, multiple supply points and multiple demand points. We developed a decomposition approach to solve the weekly problem in two phases. In the first phase we use a MIP solver to solve a tactical model that determines the destinations of full truckloads from forest areas to woodmills. In the second phase, we make use of two different methods to route and schedule the daily transportation of logs: the first one consists in using a constraint-based local search approach while the second one is a hybrid approach involving a constraint programming based model and a constraint-based local search model. These approaches have been implemented using COMET2.0. The method, was tested on two industrial cases from forest companies in Canada. 相似文献
86.
87.
Al-TiB2 master alloys have received much attention in recent years owing to their potential as efficient grain refiners for aluminum foundry alloys. In this study, the process of production of master alloys was investigated to develop a low cost method, namely, slag-metal reaction. This method can be used to fabricate Al-TiB2 master alloy in situ from the TiO2-H3BO3-Na3AlF6 and Al system. Since the price of the raw materials is low and the technology is simple, the processing technique appears to reduce the cost of the master alloy. Because of exothermic reactions, not much energy is needed to melt materials. In this process, Titanium diboride particles were formed in situ through the reactions of TiO2, H3BO3 and Na3AlF6. Results showed that when the aluminum melted, the condensed TiB2 particles that formed in situ were spherical with an average diameter of 1 μm. Furthermore, these TiB2 particles were distributed uniformly through the master alloy. 相似文献
88.
89.
90.
Ali Akbar Ramezanianpour Amirreza Pilvar Mahdi Mahdikhani Faramarz Moodi 《Construction and Building Materials》2011,25(5):2472-2479
There are several factors and test methods for evaluating the durability of concrete. In recent years a great deal of attention has been paid to research and development of relationships of these parameters for production of sustainable concretes: water penetration and Rapid Chloride Penetration Test (RCPT) methods which are most commonly used to evaluate the permeability of concrete are two of the most famous methods specified by BS EN-12390-8:2000 and ASTM C1202 respectively. Concrete surface resistivity (SR) test is also a suitable indicator for concrete penetration and chloride ion permeability. It is a non-destructive, simple, rapid and economical method that can also be used on site.The present study is an exploratory research concerned with the relationship of these methods. Based on the correlation of concrete resistivity with water penetration and Rapid Chloride Penetration Test (RCPT) results, two new models for relating these parameters are presented. 相似文献