During wound healing, the metabolic activity associated with each phase must occur in the proper sequence, at a specific time, and continue for a specific duration at an optimal intensity. Any disturbance in appropria...During wound healing, the metabolic activity associated with each phase must occur in the proper sequence, at a specific time, and continue for a specific duration at an optimal intensity. Any disturbance in appropriate thermal environment may complicate the wound healing process and may give rise to wound infection. In the presented paper a transient state two-dimensional mathematical model has been developed to analyse thermal variations in skin and subcutaneous tissue (SST) region of human limb. Due to circular shape of human limb, model has been developed in polar coordinates. The domain of the study consists of two types of tissues: abnormal tissues and normal tissues. The post surgery peripheral tissue of human limb during healing time is considered as abnormal tissues. The effect of variable density of blood vessels in dermal layer of both tissues on the physical and physiological parameters is incorporated in the model. The effect of healing on physiological parameters of abnormal tissue is incorporated by considering the physiological parameters to be function of time “t”. The effect of different climatic conditions is considered in the model. Taking into account the variable core temperature due to anatomy of arteries and variable physiological parameters in dermal layer of peripheral region, the well known Pennes’ bio heat equation is used to analyse the time-dependent temperature distribution of both normal and abnormal tissues. Comparison between temperature profiles of both normal and abnormal tissue has been done using finite element approach with bilinear shape functions in polar coordinates. A computer program in MATLAB has been developed to simulate the results.展开更多
OBJECTIVES: Skin characteristics change depending on the external environment such as UV, temperature and humidity. But the research how to affect the regional climate, age and seasonal variation on the skin condition...OBJECTIVES: Skin characteristics change depending on the external environment such as UV, temperature and humidity. But the research how to affect the regional climate, age and seasonal variation on the skin conditions was not well studied. Therefore, we investigated the seasonal variation in the skin by comparing Beijing women and Guangzhou women by age groups. METHODS: 440 healthy Chinese women participated in this study. The skin hydration, sebum secretion, TEWL and skin pH were measured on the cheek front. All the parameters were analyzed in terms of the age, season and region. RESULTS: The skin hydration in Beijing was lower than that in Guangzhou and significantly decreased during winter than summer. The sebum secretion in their 20s and 30s was significantly high in summer in both regions, and this phenomenon was more remarkable in Guangzhou (p CONCLUSIONS: Skin hydration and barrier function decreased more during a cold, dry winter than summer. The barrier dysfunctions such as an increase in TEWL and pH occurred more commonly in old age groups. The greater the differences between summer and winter climates, the greater damage to skin barrier and skin hydration. The sebum secretion was more affected by hot, humid summers. Further, the aged skin was influenced by seasonal variation except for sebum secretion.展开更多
This research presents an algorithm for face detection based on color images using three main components： skin color characteristics, hair color characteristics, and a decision structure which converts the obtained i...This research presents an algorithm for face detection based on color images using three main components： skin color characteristics, hair color characteristics, and a decision structure which converts the obtained information from skin and hair regions to labels for identifying the object dependencies and rejecting many of the incorrect decisions. Here we use face color characteristics that have a good resistance against the face rotations and expressions. This algorithm is also capable of being combined with other methods of face recognition in each stage to improve the detection.展开更多
文摘During wound healing, the metabolic activity associated with each phase must occur in the proper sequence, at a specific time, and continue for a specific duration at an optimal intensity. Any disturbance in appropriate thermal environment may complicate the wound healing process and may give rise to wound infection. In the presented paper a transient state two-dimensional mathematical model has been developed to analyse thermal variations in skin and subcutaneous tissue (SST) region of human limb. Due to circular shape of human limb, model has been developed in polar coordinates. The domain of the study consists of two types of tissues: abnormal tissues and normal tissues. The post surgery peripheral tissue of human limb during healing time is considered as abnormal tissues. The effect of variable density of blood vessels in dermal layer of both tissues on the physical and physiological parameters is incorporated in the model. The effect of healing on physiological parameters of abnormal tissue is incorporated by considering the physiological parameters to be function of time “t”. The effect of different climatic conditions is considered in the model. Taking into account the variable core temperature due to anatomy of arteries and variable physiological parameters in dermal layer of peripheral region, the well known Pennes’ bio heat equation is used to analyse the time-dependent temperature distribution of both normal and abnormal tissues. Comparison between temperature profiles of both normal and abnormal tissue has been done using finite element approach with bilinear shape functions in polar coordinates. A computer program in MATLAB has been developed to simulate the results.
文摘OBJECTIVES: Skin characteristics change depending on the external environment such as UV, temperature and humidity. But the research how to affect the regional climate, age and seasonal variation on the skin conditions was not well studied. Therefore, we investigated the seasonal variation in the skin by comparing Beijing women and Guangzhou women by age groups. METHODS: 440 healthy Chinese women participated in this study. The skin hydration, sebum secretion, TEWL and skin pH were measured on the cheek front. All the parameters were analyzed in terms of the age, season and region. RESULTS: The skin hydration in Beijing was lower than that in Guangzhou and significantly decreased during winter than summer. The sebum secretion in their 20s and 30s was significantly high in summer in both regions, and this phenomenon was more remarkable in Guangzhou (p CONCLUSIONS: Skin hydration and barrier function decreased more during a cold, dry winter than summer. The barrier dysfunctions such as an increase in TEWL and pH occurred more commonly in old age groups. The greater the differences between summer and winter climates, the greater damage to skin barrier and skin hydration. The sebum secretion was more affected by hot, humid summers. Further, the aged skin was influenced by seasonal variation except for sebum secretion.
文摘This research presents an algorithm for face detection based on color images using three main components： skin color characteristics, hair color characteristics, and a decision structure which converts the obtained information from skin and hair regions to labels for identifying the object dependencies and rejecting many of the incorrect decisions. Here we use face color characteristics that have a good resistance against the face rotations and expressions. This algorithm is also capable of being combined with other methods of face recognition in each stage to improve the detection.
