Background on non-invasive blood rheology Essay Example | Topics and Well Written Essays - 500 words

Background on non-invasive blood rheology - Essay Example (1) In rheology the viscosity of a Newtonian fluid remains constant as shear rate is proportional to shear stress. However, in a non-Newtonian fluid viscosity is not constant as shear rate and shear stress are not proportional. The plasma constituent of blood is a Newtonian fluid, while whole blood is a non-Newtonian fluid, because orientation and deformation of red blood cells result in changes of apparent viscosity at different shear rates. It is this aspect of blood and its constituents that relevant to clinical investigations. (1) Sedimentation is the rate at which the red blood cells separate from the blood plasma over time in clinical testing of blood. It is better known as erythrocyte sedimentation rate (ESR), and high ESR is indicative of inflammation in the human body. Normal values are 5-15mm/hr, depending on the technique employed. Viscosity may be considered as the internal resistance of blood to shear forces. The normal values for blood viscosity vary depending upon the techniques employed in its evaluation. Higher blood viscosity is indicative of inflammation. Blood viscosity for a given shear value is dependent on the hematocrit value, plasma viscosity, ESR and rheological properties. The higher these values over normal, the higher are the blood viscosity rates over normal. (1). Changes in blood composition occur due to several diseases and conditions, which include anemia, malnutrition and dehydration, leukemia, heart failure, kidney disease, rheumatoid arthritis, and blood loss due to trauma or surgery. Several blood tests play a role in the determination of these diseases and conditions and in tracking the efficiency of the intervention strategies. This is reason why blood tests are the normal experience during the initial clinical investigations and during the course of the treatment. (1). Anemia is a common condition that results from the deficiency in red blood cells, which is

Erikson's theory on child development Essay Example | Topics and Well Written Essays - 2000 words

Erikson's theory on child development - Essay Example mas in the ego’s relations with the family and larger social institutions at significant points in childhood, adolescence, and early, middle and late adulthood (Sadock et al, 2007). The different aspects of child development identified by Erikson (1963) are: biological, social and individual. Erikson’s most important contribution to psychology is his demarcation of the eight psychosocial stages represented by the eight ages constituting the life span of an individual. An individual’s identity is related to each stage of the lifecycle. During adolescence a conflict between identity and role confusion can arise. Ego development occurs through the stages of the life span, and is part of a child’s evolution into adolescence. As a student of Freud, Erikson took a unique perspective on Freud’s work, incorporated Freud’s primary assumptions, and broadened the network of factors considered responsible for influencing development. He extended Freudian psychoanalytic theory to focus on the ego as the fundamental component in an individual’s functioning. Erikson’s (1963) psychosocial theory of personality development is similar to Freud’s psychosexual theory of development with its emphasis on instinctual energy as a determining life force (Sadock et al, 2007). Freud’s viewpoint was that the most important determinants of development occurred during early childhood, but on the other hand Erikson believed that the most important development came later, and that development continued through the lifespan: from childhood till the last stage of life. Other differences between Freud and Erikson’s theories is that: Erikson does not stress on unconscious motives or desires, and he based his ideas on analyses of the functioning of healthy people, whereas Freud studied individuals being treated for mental health problems. Erikson considered key social interactions at each stage of development to be very important. Though he agreed that biological unfolding was