Artificial Organs Essay Example

Artificial Organs Essay Example Artificial Organs Essay Artificial Organs Essay The worldwide shortage of available donor organs provides little to no hope for patients wishing to have a chance at new life. According to the Texas Organ Sharing Alliance, there were 79,466 patients on the U. S. National Waiting List as of January 1, 2002, with only 6,148 donors in the country that year. In response to the organ shortage, scientists have made recent advances in transplant technology with the development of two new types of organ replacement: xenotransplantation and artificial organ replacement; the latter of the two types consists of either synthetic or natural materials. However, because xenotransplantation poses many health risks, artificial organs provide a more sensible, disease-free approach to organ replacement. Thus, efforts of scientists and engineers should be directed toward furthering the development of artificial and bioartificial organs and materials. Artificial organs are synthetic devices that replace injured or weakened body parts and functions. Similarly, engineered bioartificial organs serve the same purpose of organ replacement, but are produced using human cells. Xenotransplants, on the other hand, are obtained or grown using animal organs, tissues, and cells particularly those of pigs and baboons. Despite these advances in transplant technology, patients still face the problem of hyperacute rejection, which is the result of the bodys immune system protecting itself against foreign objects. Scientists and biochemists are currently developing efficient immunosuppressants to aid the body in accepting replacement organs and devices more readily and with fewer complications. Although immunosuppressants work identically for xenotransplantation and artificial organ replacement, there are a number of risks involved with xenotransplantation even after the chance of hyperacute rejection is decreased. Because immunosuppressants weaken a patients immune system, the greatest risk associated with xenotransplantation is the transmission of undetected retroviruses or diseases. The scientific community first raised concerns about this risk when Robin Weiss and

The Southern Ocean Is the Fifth and Newest World Ocean

The Southern Ocean Is the Fifth and Newest World Ocean In 2000, the International Hydrographic Organization created the fifth and newest world ocean - the Southern Ocean - from the southern portions of the Atlantic Ocean, Indian Ocean, and the Pacific Ocean. The new Southern Ocean completely surrounds Antarctica.​ The Southern Ocean extends from the coast of Antarctica north to 60 degrees south latitude. The Southern Ocean is now the fourth largest of the worlds five oceans (after the Pacific Ocean, the Atlantic Ocean, and the Indian Ocean, but larger than the Arctic Ocean). Are There Really Five Oceans? For some time, those in geographic circles have debated whether there are four or five oceans on Earth. Some consider the Arctic, Atlantic, Indian, and Pacific to be the worlds four oceans. Now, those that side with the number five can add the fifth new ocean and call it the Southern Ocean or the Antarctic Ocean, thanks to the International Hydrographic Organization (IHO). The IHO Makes a Decision The IHO, the  International Hydrographic Organization, has attempted to settle that debate through a 2000 publication that declared, named, and demarcated the Southern Ocean. The IHO published the third edition of Limits of Oceans and Seas (S-23), the global authority on the names and locations of seas and oceans, in 2000. The third edition in 2000 established the existence of the Southern Ocean as the fifth world ocean. There are 68 member countries of the IHO and membership is limited to non-landlocked countries. Twenty-eight countries responded to the IHOs request for recommendations on what to do about the Southern Ocean. All responding members except Argentina agreed that the ocean surrounding Antarctica should be created and given a single name. Eighteen of the 28 responding countries preferred calling the ocean the Southern Ocean over the alternative name Antarctic Ocean, so the former is the one that was selected. Where Is the Fifth Ocean? The Southern Ocean consists of the ocean surrounding Antarctica across all degrees of longitude and up to a northern boundary at 60 ° South latitude (which is also the limit of the United Nations Antarctic Treaty). Half of the responding countries supported 60 ° South while only seven preferred 50 ° South as the oceans northern limit. The IHO decided that, even with a mere 50% support for 60 °, since 60 °S does not run through land (50 °S does pass through South America) that 60 °S should be the northern limit of the newly demarcated ocean. Why the Need for a New Southern Ocean? A great deal of oceanographic research in recent years has been concerned with ocean circulations, first because of How Big Is the Southern Ocean? At approximately 20.3 million square kilometers (7.8 million square miles) and about twice the size of the U.S.A., the new ocean is the worlds fourth largest (following the Pacific, Atlantic, and Indian, but larger than the Arctic Ocean). The Southern Oceans lowest point is 7,235 meters (23,737 feet) below sea level in the South Sandwich Trench. The sea temperature of the Southern Ocean varies from -2 °C to 10 °C (28 °F to 50 °F). Its home to the worlds largest ocean current, the Antarctic Circumpolar Current that moves east and transports 100 times the flow of all the worlds rivers. Despite the demarcation of this new ocean, its likely that the debate over the number of oceans will continue nonetheless. After all, there is but one world ocean as all five (or four) oceans on our planet are connected.