1. Abstract 2. Introduction 3. Nature of lipid in foam cells 4. Sources of cholesterol that accumulates in foam cells 5. Significance of foam cell formation 5.1. Trapping lipid in lesions versus removing lipid from lesions 5.2. Alteration of macrophage function 6. The use of cultured macrophages to study foam cell formation 7. In vitro foam cell formation 7.1. Plasma lipoproteins 7.2. Non-lipop...

OBJECTIVES In this study we evaluated heat generation during the low-speed drilling procedure without irrigation. MATERIALS AND METHODS Ten artificial bone blocks that were similar to human D1 bone were used in this study. The baseline temperature was 37.0℃. We drilled into 5 artificial bone blocks 60 times at the speed of 50 rpm without irrigation. As a control group, we drilled into an addi...

Oil and gas well drilling activities are associated with numerous hazards which have the potential to cause injury or harm for people, property and the environment. These hazards are also a threat for the reputation of drilling companies. To prevent accidents and undesired events in drilling operations it is essential to identify, evaluate, assess and control the attendant risks. In this work, ...

Drilling procedure is widely used in orthopedic surgery to position reduced fractured bones and prosthetic components. However, successful execution of bone drilling requires a high level of dexterity and experience, because the drilling resistance is large and sometimes vibrates violently to difficultly grasp the hand-piece or even break the slender drill. This paper introduces haptic function...

In this research, finite element analysis of the conventional drilling and vibration assisted drilling is carried out. The ABAQUS software is employed for FE analysis. The Johnson-Cook models for both plastic deformation and damage are employed for FE simulation.The results of the FE analysis are then verified with experimental results in both conventional and vibration assisted drilling on Al ...

The effect of yeast strain and aging time on the chemical composition, analytical, and sensory foam properties of sparkling ciders has been studied. The analytical foam parameters (foamability, HM; Bikerman coefficient, sigma; and foam stability time, T(s)) were significantly influenced by aging and yeast strain. The sensory attributes (initial foam, foam area persistence, bubble size, foam col...

Bone fracture due to an accident, aging or diseases is a feature of everyday life. One of the principal methods of repair and reconstruction of such a fracture is based on drilling the bone and fixing its separate parts together using screws, wires and plates. Morphology of the drilled hole surface and fixative components such as screws, pins and hooks influences strength of the bonds between t...

The dynamic model of a drill in drilling process was proposed and investigated in this study. To assure a good drilling quality, the vibration variation on the drill tips during high speed drilling is needed to be investigated. A pre-twisted beam is used to simulate the drill. The moving Winkler-Type elastic foundation is used to characterize the tip boundary variation in drilling. Due to the v...

The main affecting parameter for Delamination of the composites and in turn the failure of composites is the Thrust force. In the present work an attempt has been made in order to investigate the Thrust force generated during drilling of the TiO2 and ZnS filled Glass Fabric Reinforced Polymer Matrix Composites (GFRP). The volume fractions in the matrix were chosen as 1, 2 and3%. A plan of exper...

RATIONALE Retrograde drilling is a well accepted procedure for osteochondral lesion of the talus and subchondral cyst with intact overlying cartilage. It has good results in most reports. Compared to anterograde drilling, retrograde drilling can protect the integrity of the articular cartilage. The purpose of this study was to evaluate the suitability of using retrograde drilling for osteochond...