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Showing posts with label Energy. Show all posts
Showing posts with label Energy. Show all posts

Thursday, January 8, 2009

Skincare Business

Looking Younger – The Commitment
Your eyes do not only serve as your key in functioning optimally everyday. They also can bring out the beauty in you. You can do it naturally but it can be enhanced further with the use of makeup. Try these styles and you will enjoy it.


Acne Skin Care Treatment Product
Finding beauty products with natural ingredients is important. Skin is the largest organ of the human body. Skin can absorb many things.


Select The Right Moisturizer For Your Skin
Shea Butter is a remarkable ingredient in the skin care business. It is used by many cosmetic companies as a must have. Have you ever thought where does this wonderful ingredient come from and what it can do for you. Find out more by reading this article.

Monday, January 8, 2007

Blood Oxygenation

Blood oxygenation is measured in several ways, but the most important measure is the hemoglobin (Hb) saturation percentage. This is a non-linear (sigmoidal) function of the partial pressure of oxygen. About 98.5% of the oxygen in a sample of arterial blood in a healthy human breathing air at normal pressure is chemically combined with the Hb. Only 1.5% is physically dissolved in the other blood liquids and not connected to Hb. The hemoglobin molecule is the primary transporter of oxygen in mammals and many other species .

With the exception of pulmonary and umbilical arteries and their corresponding veins, arteries carry oxygenated blood away from the heart and deliver it to the body via arterioles and capillaries, where the oxygen is consumed; afterwards, venules and veins carry deoxygenated blood back to the heart.

Differences in infrared absorption between oxygenated and deoxygenated blood form the basis for realtime oxygen saturation measurement in hospitals and ambulances.

Under normal conditions in humans at rest, haemoglobin in blood leaving the lungs is about 98-99% saturated with oxygen. In a healthy adult at rest, deoxygenated blood returning to the lungs is still approximately 75% saturated. Increased oxygen consumption during sustained exercise reduces the oxygen saturation of venous blood, which can reach less than 15% in a trained athlete; although breathing rate and blood flow increase to compensate, oxygen saturation in arterial blood can drop to 95% or less under these conditions. Oxygen saturation this low is considered dangerous in an individual at rest (for instance, during surgery under anesthesia): "As a general rule, any condition which leads to a sustained mixed venous saturation of less than 50% will be poorly tolerated and a mixed venous saturation of less than 30% should be viewed as a medical emergency."

A fetus, receiving oxygen via the placenta, is exposed to much lower oxygen pressures (about 20% of the level found in an adult's lungs) and so fetuses produce another form of hemoglobin with a much higher affinity for oxygen (hemoglobin F) in order to extract as much oxygen as possible from this sparse supply.

Substances other than oxygen can bind to the hemoglobin; in some cases this can cause irreversible damage to the body. Carbon monoxide for example is extremely dangerous when absorbed into the blood. When combined with the hemoglobin, it irreversibly makes carboxyhemoglobin which reduces the volume of oxygen that can be carried in the blood. This can very quickly cause suffocation, as oxygen is vital to many organisms (including humans). This damage can occur when smoking a cigarette (or similar item) or in event of a fire. Thus carbon monoxide is considered far more dangerous than the actual fire itself because it reduces the oxygen carrying content of the blood.

Production and Degradation of Blood

Blood cells are produced in the bone marrow; the process is termed hematopoiesis. The proteinaceous component (including clotting proteins) is produced overwhelmingly in the liver, while hormones are produced by the endocrine glands and the watery fraction regulated by the hypothalamus and maintained by the kidney and indirectly by the gut.

Blood cells are degraded by the spleen and the Kupffer cells in the liver. The liver also clears some proteins, lipids and amino acids. The kidney actively secretes waste products into the urine. Erythrocytes usually live up to 120 days before they are systematically replaced by new erythrocytes created by the process of hematopoiesis.

Sunday, January 7, 2007

Anaerobic Exercise

Anaerobic means "without oxygen", and refers to the energy exchange in living tissue that is independent of oxygen. Anaerobic exercise is brief, high intensity activity where anaerobic metabolism is taking place in muscles. During extended periods of exercise aerobic metabolism supplies the bulk of the energy and the exercise is termed aerobic exercise.

Examples of anaerobic exercise include weight lifting, sprinting, and jumping; any exercise that consists of short exertion, high-intensity movement, is an anaerobic exercise. Anaerobic exercise is typically used by athletes in non-endurance sports to build power and by body builders to build muscle mass. Muscles that are trained under anaerobic conditions develop biologically different giving them greater performance in short duration-high intensity activities.

Aerobic exercise, on the other hand, includes lower intensity activities performed for longer periods of time. Activities like walking, running, swimming, and cycling require a great deal of oxygen to generate the energy needed for prolonged exercise.

here are two types of anaerobic energy system, the ATP-CP energy system, which uses creatine phosphate as the main energy source, and the lactic-acid (or anaerobic glycolysis) system that uses glucose (or glycogen) in the absence of oxygen. The latter is an inefficient use of glucose and produces by-products that are thought to be detrimental to muscle function.

The lactic-acid system is the dominant energy system during high to maximal intensity exercise over short durations (up to about 1 min), but the lactic acid system can still provide a proportion of the required energy during aerobic exercise, as the body has the capacity to get rid of the anaerobic by-products at a certain rate. The efficiency of by-product removal by muscles can improve through training.