Study on Biomechanical Response and Subjective Fatigue Symptoms of Human Body Wearing Personal Protective Equipments

Roller Coasters are one of the most popular amusement devices in use throughout the world. In their most basic form, roller coasters consist of a track system in which a car or train rolls under the force of gravity. The major design constraints of roller coasters are determined by the level of force and acceleration that the human body can safely withstand. These forces are commonly measured in multiples of the Earth’s gravitational acceleration, and are termed “G” forces.

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Could an isolated human body lower limb model predict leg biomechanical response of Chinese pedestrians in vehicle collisions?

Acta of Bioengineering and Biomechanics ◽

10.37190/abb-01630-2020-04 ◽

2020 ◽

Vol 22 (3) ◽

Author(s):

Huaxing Ma ◽

Zhengyu Mao ◽

Guibing Li ◽

Lingbo Yan ◽

Fuhao Mo

Keyword(s):

Body Mass ◽

Human Body ◽

Lower Limb ◽

Injury Risk ◽

Upper Body ◽

Fe Model ◽

Lower Limb Injury ◽

Vehicle Collisions ◽

Front End ◽

Biomechanical Response

Purpose: The purpose of the current study was to investigate whether an isolated human body lower limb FE model could predict leg kinematics and biomechanical response of a full body Chinese pedestrian model in vehicle collisions. Methods: A human body lower limb FE model representing midsize Chinese adult male anthropometry was employed with different upper body weight attachments being evaluated by comparing the predictions to those of a full body pedestrian model in vehicle-to-pedestrian collisions considering different front-end shapes. Results: The results indicate that upper body mass has a significant influence on pedestrian lower limb injury risk, the effect varies from vehicle front-end shape and is more remarkable to the femur and knee ligaments than to the tibia. In particular, the upper body mass can generally increase femur and knee ligaments injury risk, but has no obvious effect on the injury risk of tibia. The results also show that a higher attached buttock mass is needed for isolated pedestrian lower limb model for impacts with vehicles of higher bonnet leading edge. Conclusions: The findings of this study may suggest that it is necessary to consider vehicle shape variation in assessment of vehicle pedestrian protection performance and leg-form impactors with adaptive upper body mass should be used for vehicles with different front-end shapes, and the use of regional leg-form impactor modeling the local anthropometry to evaluate the actual lower limb injury of pedestrians in different countries and regions.

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Microstructural comparison of synthetic bioceramics with natural bioceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084491 ◽

1991 ◽

Vol 49 ◽

pp. 38-39

Author(s):

Shulin Wen ◽

Jingwei Feng ◽

A. Krajewski ◽

A. Ravaglioli

Keyword(s):

Recent Work ◽

Human Body ◽

Human Tissues ◽

Main Constituent ◽

Laboratory Furnace ◽

Chinese Adult ◽

Human Enamel ◽

Biological Compatibility ◽

Synthetic Hydroxyapatite ◽

Synthetic Work

Hydroxyapatite bioceramics has attracted many material scientists as it is the main constituent of the bone and the teeth in human body. The synthesis of the bioceramics has been performed for years. Nowadays, the synthetic work is not only focused on the hydroapatite but also on the fluorapatite and chlorapatite bioceramics since later materials have also biological compatibility with human tissues; and they may also be very promising for clinic purpose. However, in comparison of the synthetic bioceramics with natural one on microstructure, a great differences were observed according to our previous results. We have investigated these differences further in this work since they are very important to appraise the synthetic bioceramics for their clinic application.The synthetic hydroxyapatite and chlorapatite were prepared according to A. Krajewski and A. Ravaglioli and their recent work. The briquettes from different hydroxyapatite or chlorapatite powders were fired in a laboratory furnace at the temperature of 900-1300°C. The samples of human enamel selected for the comparison with synthetic bioceramics were from Chinese adult teeth.

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Study on erythrocytes by SEM photogrammetry (SEMP) technique

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161187 ◽

1990 ◽

Vol 48 (3) ◽

pp. 724-725

Author(s):

Tong Wensheng ◽

Lu Lianhuang ◽

Zhang Zhijun

Keyword(s):

Quantitative Analysis ◽

Cell Membrane ◽

Clinical Diagnosis ◽

Human Body ◽

Blood Cells ◽

Three Dimensional ◽

Normal Person ◽

Blood Disease ◽

Computation Technique ◽

Important Basis

This is a combined study of two diffirent branches, photogrammetry and morphology of blood cells. The three dimensional quantitative analysis of erythrocytes using SEMP technique, electron computation technique and photogrammetry theory has made it possible to push the study of mophology of blood cells from LM, TEM, SEM to a higher stage, that of SEM P. A new path has been broken for deeply study of morphology of blood cells.In medical view, the abnormality of the quality and quantity of erythrocytes is one of the important changes of blood disease. It shows the abnormal blood—making function of the human body. Therefore, the study of the change of shape on erythrocytes is the indispensable and important basis of reference in the clinical diagnosis and research of blood disease.The erythrocytes of one normal person, three PNH Patients and one AA patient were used in this experiment. This research determines the following items: Height;Length of two axes (long and short), ratio; Crevice in depth and width of cell membrane; Circumference of erythrocytes; Isoline map of erythrocytes; Section map of erythrocytes.

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