Coagulation Definition (Chemistry and Biology)

Coagulation Definition (Chemistry and Biology) Coagulation is a gelling or clumping of particles, typically in a colloid. The term typically applies to the thickening of a liquid or sol, usually when protein molecules cross-link. When coagulation or clotting occurs in blood, it proceeds immediately after blood vessel damage. Two processes occur. Platelets change and the subendothelian tissue factor is exposed to plasma Factor VII, which ultimately forms fibrin. Primary hemostasis occurs when platelets plug the injury. Secondary hemostasis occrs as clotting factors strengthen the platelet plug with fibrin factors. Also Known As: coagulate, coagulating, clotting Examples of Coagulation Milk proteins coagulate to thicken the mixture that forms yogurt. Blood platelets coagulate blood to seal a wound. Pectin gels (coagulates) a jam. Gravy coagulates as it cools. Sources David Lillicrap; Nigel Key; Michael Makris; Denise OShaughnessy (2009). Practical Hemostasis and Thrombosis. Wiley-Blackwell. pp. 1–5. ISBN 1-4051-8460-4.Pallister CJ, Watson MS (2010). Haematology. Scion Publishing. pp. 336–347. ISBN 1-904842-39-9.

John Kay and His Impact on Weaving

John Kay and His Impact on Weaving In 1733, John Kay invented the flying shuttle, an improvement to weaving looms and a key contribution to the  Industrial Revolution. Early Years Kay was born on June 17, 1704,  in the  Lancashire  hamlet of  Walmersley. His  father Robert was a farmer and wool manufacturer.  Robert died before John was born   His mother was responsible for educating him until she remarried. John Kay was just a young man when he became the manager of one of his fathers mills. Kay developed skills as a machinist and engineer. He made many improvements to the machines in the mill. He  apprenticed with a  hand-loom reed  maker.  He designed a  metal substitute  for the natural reed that proved popular enough for him to sell throughout England.  After traveling the country, making and fitting wire reeds, he returned to his home and, on June 29, 1725, both he and his brother, William, married Bury women.   The Flying Shuttle The flying shuttle was an improvement to looms that enabled weavers to weave faster. The original shuttle contained a bobbin on to which the weft (weaving term for the crossways yarn) yarn was wound. It was normally pushed from one side of the warp (weaving term for the series of yarns that extended lengthways in a loom) to the other side by hand. Large looms needed two weavers to throw the shuttle. The flying shuttle was thrown by a leaver that could be operated by one weaver.  The shuttle was able to do the work of two people even more quickly.   In Bury, John Kay continued to design improvements to textile machinery; in 1730 he patented a  cording  and  twisting  machine for  worsted. In 1753, Kays home was attacked by textile workers who were angry that his inventions might take work away from them. Kay fled England for France where he died in poverty around 1780. Influence and Legacy of  John Kay Kays invention paved the way for mechanical power looms, however, the technology would have to wait another 30 years before a  power loom  was invented by Edmund Cartwright in 1787. John Kays son, Robert, stayed in  Britain,   and in 1760 developed the drop-box, which enabled looms to use multiple flying shuttles at the same time, allowing multicolor wefts. His son John had long lived with his father in France. In 1782 he provided an account of his fathers troubles to  Richard Arkwright, who sought to highlight problems with patent defense in a parliamentary petition. In the 1840s,  Thomas Sutcliffe  (one of Kays great-grandsons) campaigned to promote a  Colchester  heritage for Kays family. In 1846 he unsuccessfully sought a parliamentary  grant  for Kays descendants (in compensation for his ancestors treatment in England).  He was inaccurate in the details of his grandfathers  genealogy  and story, and his Fanciful and Erroneous Statements were discredited by John Lords detailed examination of  primary sources. In Bury, Kay has become a local hero: there are still several  pubs  named after him, as are the Kay Gardens.