Determination and Evaluation of Metal Oxide Toxicity on Dermal Fibroblasts by Using the Impedance-Based Assay System

Metal oxides have been widely used in various applications such as biomedical, commercial and environmental, due to their unique physicochemical properties. As the use of metal oxides increase worldwide, their exposure to the living systems also increases. It is therefore necessary to understand their potential harmful effects on human and environment health. In this study, dermal fibroblasts were exposed to bulk zinc oxide (0.1, 1, 10, 50, and 100 μg/mL) for 6 and 48 h. After exposure, changes in cell viability, morphology, membrane damage and zinc oxide uptake were investigated. The response of dermal fibroblasts exposed to different concentrations of bulk zinc oxide was monitored in real-time using an impedance-based assay system. Results demonstrated that zinc oxide at 50 and 100 μg/mL showed significant toxic effects compared to the control cell cultures

Evaluation Model for Supply Chain Agility in a Fuel Oil Supply Company

Agile supply chain must be able to respond quickly to fluctuations, delays and unforeseen actions to meet customer expectations, having competitive advantage and develop their business activities. To achieve this, managers must optimize and improve logistics operations efficiently, and meet demand easily by applying the latest technology and automation. As a result, providing data in real-time to meet demand on time is important to obtain competitive advantage in a competitive environment. In this study, the most important agility factors are weighted and prioritized considering Fuel Oil Supply Company. In the evaluation process Interval-Valued Pythagorean Fuzzy (IVPF)-Analytic Hierarchy Process (AHP) is used. As a result, Flexibility to changes is obtained as the most important agile factor in supply chain for Fuel Oil Supply Company

The Effect of Reinforcement Ratio on Mechanical Properties of AA2024 Matrix MgO+SiC Reinforced Hybrid Composites

—In today's rapidly developing technologies, the place and importance of composite materials is gradually increasing and the studies carried out in these fields are continuing rapidly. While metal matrix composite materials form part of these studies, especially the applications of ceramic particle reinforced aluminium composites are expanding. Generally, different types and amounts of SiC, B4C, SiO2, Al2O3, TiC, MgO, TiB, etc. are added into the aluminium alloys of different quality ceramic reinforcement materials are added. However, composite materials are generally produced by using a variety of these reinforcing materials and are subject to scientific studies. In this experimental study; two different ceramic-based reinforcing materials, SiC and MgO, were mixed equally and then hybrid composite materials were produced with 3%, 6% and 12% (weight) reinforcements in 2024 quality aluminium alloy by vortex method. Density, hardness, transverse fracture and abrasive wear tests were carried out and as well as the microstructures of the composite materials were examined. According to the results, the porosity in the composite structure increased and the density decreased due to the increasing reinforcement ratio. On the other hand, the hardness of the composites increased with increasing reinforcement ratio. However, their cross fracture, and abrasion resistance decreased. It was concluded that it is useful to try different process parameters in order to obtain better mechanical properties in such composites produced by vortex method

A Weighted Multiobjective Optimization Method for Mixed-Model Assembly Line Problem

Mixed-model assembly line (MMAL) is a type of assembly line where several distinct models of a product are assembled. MMAL is applied in many industrial environments today because of its greater variety in demand. This paper considers the objective of minimizing the work overload (i.e., the line balancing problem) and station-to-station product flows. Generally, transportation time between stations are ignored in the literature. In this paper, Multiobjective Mixed-Integer Programming (MOMIP) model is presented to optimize these two criteria simultaneously. Also, this MOMIP model incorporates a practical constraint that allows to add parallel stations to assembly line to decrease higher station time. In the last section, MOMIP is applied to optimize the cycle time and transportation time simultaneously in mixed-model assembly line of a real consumer electronics firm in Turkey, and computational results are presented