source: http://www.biomaterials.org/week/bio9.cfm
In anatomy, the heart valves are valves in the heart that maintain the unidirectional flow of blood by opening and closing depending on the difference in pressure on each side. The mechanical equivalent of the heart valves would be the reed valves.There are four valves of the heart (not counting the valve of the coronary sinus and valve of the inferior vena cava):
· The two atrioventricular (AV) valves ensure blood flows from the atria to the ventricles, and not the other way.
· The two semilunar (SL) valves are present in the arteries leaving the heart, and they prevent blood flowing back from the arteries into the ventricles. The sound of the heart valves shutting causes the heart sounds.Mechanical heart valves are prosthetics designed to replicate the function of the natural valves of the human heart. The human heart contains four valves: tricuspid valve, pulmonic valve, mitral valve and aortic valve. Their main purpose is to maintain unimpeded forward flow through the heart and from the heart into the major blood vessels connected to the heart, the pulmonary artery and the aorta. As a result of a number of disease processes, both acquired and congenital, any one of the four heart valves may malfunction and result in either stenosis (impeded forward flow) and/or backward flow (regurgitation). Either process burdens the heart and may lead to serious problems including heart failure. A mechanical heart valve is intended to replace a diseased heart valve with its prosthetic equivalent.There are two basic types of valves that can be used for aortic valve replacement, mechanical and tissue valves. Modern mechanical valves can last indefinitely (the equivalent of over 50,000 years in an accelerated valve wear tester). However, current mechanical heart valves all require lifelong treatment with a blood thinner, e.g. warfarin, which requires monthly blood tests to monitor. This process of thinning the blood is called anticoagulation. Tissue heart valves, in contrast, do not require the use of anticoagulant drugs due to the improved blood flow dynamics resulting in less red cell damage and hence less clot formation. Their main weakness however, is their limited lifespan. Traditional tissue valves, made of pig heart valves, will last on average 15 years before they require replacement
Sunday, October 18, 2009
Fodder
source: www.wikipedia.org/wiki/animalfeed
In agriculture, fodder or animal feed is any foodstuff that is used specifically to feed domesticated livestock such as cattle, goats, sheep, horses, chickens and pigs. Most animal feed is from plants but some is of animal origin. "Fodder" refers particularly to food given to the animals (including plants cut and carried to them), rather than that which they forage for themselves (see forage). It includes hay, straw, silage, compressed and pelleted feeds, oils and mixed rations, and also sprouted grains and legumes.
The worldwide animal feed industry consumed 635 million tons of feed (compound feed equivalent) in 2006, with an annual growth rate of about 2%. The use of agricultural land to grow feed rather than human food can be controversial; some types of feed, such as corn (maize), can also serve as human food, while others such as grass cannot. Some agricultural by-products which are fed to animals may be considered unsavory by human consumers.
In the past, mad cow disease spread through the inclusion of ruminant meat and bone meal in cattle feed due to prion contamination. This practice is now banned in most countries where it has occurred. Some animals have a lower tolerance for spoiled or moldy fodder than others, and certain types of molds, toxins, or poisonous weeds inadvertently mixed into a food source may cause economic losses due to sickness or death of the animals.
In agriculture, fodder or animal feed is any foodstuff that is used specifically to feed domesticated livestock such as cattle, goats, sheep, horses, chickens and pigs. Most animal feed is from plants but some is of animal origin. "Fodder" refers particularly to food given to the animals (including plants cut and carried to them), rather than that which they forage for themselves (see forage). It includes hay, straw, silage, compressed and pelleted feeds, oils and mixed rations, and also sprouted grains and legumes.
The worldwide animal feed industry consumed 635 million tons of feed (compound feed equivalent) in 2006, with an annual growth rate of about 2%. The use of agricultural land to grow feed rather than human food can be controversial; some types of feed, such as corn (maize), can also serve as human food, while others such as grass cannot. Some agricultural by-products which are fed to animals may be considered unsavory by human consumers.
In the past, mad cow disease spread through the inclusion of ruminant meat and bone meal in cattle feed due to prion contamination. This practice is now banned in most countries where it has occurred. Some animals have a lower tolerance for spoiled or moldy fodder than others, and certain types of molds, toxins, or poisonous weeds inadvertently mixed into a food source may cause economic losses due to sickness or death of the animals.
Drug Coatings
source: http://www.biomaterials.org/week/bio6.cfm
A drug is a substance, such as a pharmaceutical product, used in or on the surface of the body to diagnose, cure, mitigate, treat, or prevent disease, or to otherwise affect the structure or function of the body. It is usually synthesized outside of an organism, but introduced into an organism to produce its action. That is, when taken into the organisms body, it will produce some effects or alter some bodily functions (such as relieving symptoms, curing diseases or used as preventive medicine or any other purposes).Note that natural endogenous biochemicals (such as hormones) can bind to the same receptor in the cell, producing the same effect as a drug. Thus, drug is merely an artificial definition that distinguishes whether that molecule is synthesized within an organism or outside an organism. For instance, insulin is a hormone that is synthesized in the body; it is considered as a hormone when it is synthesized by the pancreas inside the body, but if it is introduced into the body from outside, it is considered as a drug.It is a substance which is not food,[1] and which, when ingested, affects the functioning of the mind, or the body, or both. However, under the philosophy of Chinese medicine, food is also considered a drug as it affects particular parts of body and cures some diseases. Thus, food does satisfy the above definition of drug so long as ingestion of it would alter some bodily functions.Many times drugs are encapsulated with polymers or sugars which serve as a biodegradable mechanisms that allows them to dissolve at specific parts of the digestive track.
A drug is a substance, such as a pharmaceutical product, used in or on the surface of the body to diagnose, cure, mitigate, treat, or prevent disease, or to otherwise affect the structure or function of the body. It is usually synthesized outside of an organism, but introduced into an organism to produce its action. That is, when taken into the organisms body, it will produce some effects or alter some bodily functions (such as relieving symptoms, curing diseases or used as preventive medicine or any other purposes).Note that natural endogenous biochemicals (such as hormones) can bind to the same receptor in the cell, producing the same effect as a drug. Thus, drug is merely an artificial definition that distinguishes whether that molecule is synthesized within an organism or outside an organism. For instance, insulin is a hormone that is synthesized in the body; it is considered as a hormone when it is synthesized by the pancreas inside the body, but if it is introduced into the body from outside, it is considered as a drug.It is a substance which is not food,[1] and which, when ingested, affects the functioning of the mind, or the body, or both. However, under the philosophy of Chinese medicine, food is also considered a drug as it affects particular parts of body and cures some diseases. Thus, food does satisfy the above definition of drug so long as ingestion of it would alter some bodily functions.Many times drugs are encapsulated with polymers or sugars which serve as a biodegradable mechanisms that allows them to dissolve at specific parts of the digestive track.
Sunday, August 23, 2009
THE PRODUCTION OF TEMPEH...
Tempeh, or tempe in Javanese, is made by a natural culturing and controlled fermentation process that binds soybeans into a cake form. It is especially popular on the island of Java, where it is a staple source of protein. Like tofu, tempeh is made from soybeans, but tempeh is a whole soybean product with different nutritional characteristics and textural qualities. Tempeh's fermentation process and its retention of the whole bean give it a higher content of protein, dietary fiber, and vitamins compared to tofu, as well as firmer texture and stronger flavor. Tofu, by contrast, is said to be more versatile in dishes. Because of its nutritional value, tempeh is used worldwide in vegetarian cuisine; some consider it to be a meat analogue. Even long before Westerners found and realized its rich nutritional value, tempeh was referred to as “Javanese meat.”
Tempeh begins with whole soybeans, which are softened by soaking and dehulled, then partly cooked. Specialty tempehs may be made from other types of beans, wheat, or may include a mixture of beans and whole grains.
A mild acidulent, usually vinegar, may be added in order to lower the pH and create a selective environment that favors the growth of the tempeh mold over competitors. A fermentation starter containing the spores of fungus Rhizopus oligosporus is mixed in. The beans are spread into a thin layer and are allowed to ferment for 24 to 36 hours at a temperature around 30°C (86°F). In good tempeh, the beans are knitted together by a mat of white mycelia.
Under conditions of lower temperature, or higher ventilation, gray or black patches of spores may form on the surface—this is not harmful, and should not affect the flavor or quality of the tempeh[citation needed]. This sporulation is normal on fully mature tempeh. A mild ammonia smell may accompany good tempeh as it ferments, but it should not be overpowering. In Indonesia, ripe tempeh (two or more days old) is considered a delicacy.
Tempeh begins with whole soybeans, which are softened by soaking and dehulled, then partly cooked. Specialty tempehs may be made from other types of beans, wheat, or may include a mixture of beans and whole grains.
A mild acidulent, usually vinegar, may be added in order to lower the pH and create a selective environment that favors the growth of the tempeh mold over competitors. A fermentation starter containing the spores of fungus Rhizopus oligosporus is mixed in. The beans are spread into a thin layer and are allowed to ferment for 24 to 36 hours at a temperature around 30°C (86°F). In good tempeh, the beans are knitted together by a mat of white mycelia.
Under conditions of lower temperature, or higher ventilation, gray or black patches of spores may form on the surface—this is not harmful, and should not affect the flavor or quality of the tempeh[citation needed]. This sporulation is normal on fully mature tempeh. A mild ammonia smell may accompany good tempeh as it ferments, but it should not be overpowering. In Indonesia, ripe tempeh (two or more days old) is considered a delicacy.
Sunday, July 19, 2009
Internal combustion engine
the article that i've read this week......................................
source:http://en.wikipedia.org/wiki/Car_engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidiser (usually air) in a combustion chamber. In an internal combustion engine the expansion of the high temperature and pressure gases, that are produced by the combustion, directly apply force to a movable component of the engine, such as the pistons or turbine blades and by moving it over a distance, generate useful mechanical energy
The term internal combustion engine usually refers to an engine in which combustion is intermittent, such as the more familiar four-stroke and two-stroke piston engines, along with variants, such as the Wankel rotary engine. A second class of internal combustion engines use continuous combustion: gas turbines, jet engines and most rocket engines, each of which are internal combustion engines on the same principle as previously described.
The internal combustion engine (or ICE) is quite different from external combustion engines, such as steam or Stirling engines, in which the energy is delivered to a working fluid not consisting of, mixed with or contaminated by combustion products. Working fluids can be air, hot water, pressurised water or even liquid sodium, heated in some kind of boiler by fossil fuel, wood-burning, nuclear, solar etc.
A large number of different designs for ICEs have been developed and built, with a variety of different strengths and weaknesses. While there have been and still are many stationary applications, the real strength of internal combustion engines is in mobile applications and they completely dominate as a power supply for cars, aircraft, and boats, from the smallest to the biggest. Only for hand-held power tools do they share part of the market with battery powered devices. Powered by an energy-dense fuel (nearly always liquid, derived from fossil fuels) the ICE delivers an excellent power-to-weight ratio with few safety or other disadvantages.
source:http://en.wikipedia.org/wiki/Car_engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidiser (usually air) in a combustion chamber. In an internal combustion engine the expansion of the high temperature and pressure gases, that are produced by the combustion, directly apply force to a movable component of the engine, such as the pistons or turbine blades and by moving it over a distance, generate useful mechanical energy
The term internal combustion engine usually refers to an engine in which combustion is intermittent, such as the more familiar four-stroke and two-stroke piston engines, along with variants, such as the Wankel rotary engine. A second class of internal combustion engines use continuous combustion: gas turbines, jet engines and most rocket engines, each of which are internal combustion engines on the same principle as previously described.
The internal combustion engine (or ICE) is quite different from external combustion engines, such as steam or Stirling engines, in which the energy is delivered to a working fluid not consisting of, mixed with or contaminated by combustion products. Working fluids can be air, hot water, pressurised water or even liquid sodium, heated in some kind of boiler by fossil fuel, wood-burning, nuclear, solar etc.
A large number of different designs for ICEs have been developed and built, with a variety of different strengths and weaknesses. While there have been and still are many stationary applications, the real strength of internal combustion engines is in mobile applications and they completely dominate as a power supply for cars, aircraft, and boats, from the smallest to the biggest. Only for hand-held power tools do they share part of the market with battery powered devices. Powered by an energy-dense fuel (nearly always liquid, derived from fossil fuels) the ICE delivers an excellent power-to-weight ratio with few safety or other disadvantages.
Sunday, July 12, 2009
MY EXPERIENCE.....
for the first time i arrived at the ump i was shocked.....
wow.....what a big place...
there are so many questions in my mind.....
how can i survive in this huge place????
do i need to walk to my class???
im not an independent girl....
do i need to wash my own clothes???
do i have to wake up in the morning on my own......
mom dad please help me!!!!!!!!!!
how can i live without you guys???
how can i live without my siblings???
who are going to help me here????
there's no one i know here.......
i don't want to live here...
what are going to happen to me then???
~to be continue~
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