Ch17 Blood free essay sample

Blood Objectives Overview: Blood Composition and Functions 1. Describe the composition and physical characteristics of whole blood. Explain why it is classified as a connective tissue. 2. List eight functions of blood. Blood Plasma 3. Discuss the composition and functions of plasma. Formed Elements 4. Describe the structure, function, and production of erythrocytes. 5. Describe the chemical makeup of hemoglobin. 6. Give examples of disorders caused by abnormalities of erythrocytes. Explain what goes wrong in each disorder. 7. List the classes, structural characteristics, and functions of leukocytes. 8. Describe how leukocytes are produced. 9. Give examples of leukocyte disorders, and explain what goes wrong in each disorder. 10. Describe the structure and function of platelets. Hemostasis 11. Describe the processes of hemostasis. List factors that limit clot formation and prevent undesirable clotting. 12. Give examples of hemostatic disorders. Indicate the cause of each condition. Transfusion and Blood Replacement 13. Describe the ABO and Rh blood groups. Explain the basis of transfusion reactions. 14. Describe fluids used to replace blood volume and the circumstances for their use. Diagnostic Blood Tests 15. Explain the diagnostic importance of blood testing. Developmental Aspects of Blood 16. Describe changes in the sites of blood production and in the type of hemoglobin produced after birth. 17. Name some blood disorders that become more common with age. Chapter Outline I. Overview: Blood Composition and Functions (pp. 635–636; Fig. 17. 1) A. Components (p. 635; Fig. 17. 1) 1. Blood is a specialized connective tissue consisting of living cells, called formed elements, suspended in a nonliving fluid matrix, blood plasma. 2. Blood that has been centrifuged separates into three layers: erythrocytes, the buffy coat, and plasma. . The blood hematocrit represents the percentage of erythrocytes in whole blood. B. Physical Characteristics and Volume (p. 635) 1. Blood is a slightly basic (pH = 7. 35–7. 45) fluid that has a higher density and viscosity than water, due to the presence of formed elements. 2. Normal blood volume in males is 5–6 liters, and 4–5 liters for females. C. Functions (pp. 635–636) 1. Blood is the medium for delivery of oxygen and nutrients, removal of metabolic wastes to elimination sites, and distribution of hormones. 2. Blood aids in regulating body temperature, body fluid pH, and fluid volume within fluid compartments. . Blood protects against excessive blood loss through the clotting mechanism, and from infection through the immune system. II. Blood Plasma (p. 636; Table 17. 1) A. Blood plasma consists of mostly water (90%), and solutes including nutrients, gases, hormones, wastes, products of cell activity, ions, and proteins (p. 636; Table 17. 1). B. Plasma proteins account for 8% of plasma solutes, mostly albumin, which function as carriers (p. 636). III. Formed Elements (pp. 637–649; Figs. 17. 2–17. 12; Table 17. 2) A. Erythrocytes (pp. 637–643; Figs. 17. 2–17. 8) 1. Erythrocytes, or red blood cells, are small cells that are biconcave in shape. They lack nuclei and most organelles, and contain mostly hemoglobin. a. Hemoglobin is an oxygen-binding pigment that is responsible for the transport of most of the oxygen in the blood. b. Hemoglobin is made up of the protein globin bound to the red heme pigment. 2. Production of Erythrocytes a. Hematopoiesis, or blood cell formation, occurs in the red bone marrow. b. Erythropoiesis, the formation of erythrocytes, begins when a myeloid stem cell is transformed to a proerythroblast, which develops into mature erythrocytes. . Erythrocyte production is controlled by the hormone erythropoietin. d. Dietary requirements for erythrocyte formation include iron, vitamin B12, and folic acid, as well as proteins, lipids, and carbohydrates. e. Blood cells have a short life span due to the lack of nuclei and organelles; destruction of dead or dying blood cells is accomplished by macrophages. 3. Erythrocyte Disorders a. Anemias are characterized by a deficiency in RBCs. b. Polycythemia is characterized by an abnormal excess of RBCs. B. Leukocytes (pp. 643–648; Figs. 17. 9–17. 11; Table 17. 2) 1. Leukocytes, or white blood cells, are the only formed elements that are complete cells and make up less than 1% of total blood volume. 2. Leukocytes are critical to our defense against disease. 3. Granulocytes are a main group of leukocytes characterized as large cells with lobed nuclei and visibly staining granules; all are phagocytic. a. Neutrophils are the most numerous type of leukocyte. They are chemically attracted to sites of inflammation and are active phagocytes. b. Eosinophils are relatively uncommon and attack parasitic worms. c. Basophils are the least numerous leukocyte and release histamine to promote inflammation. . Agranulocytes are a main group of lymphocytes that lack visibly staining granules. a. T lymphocytes directly attack virus-infected and tumor cells; B lymphocytes produce antibody cells. b. Monocytes become macrophages and activate T lymphocytes. 5. Production and Life Span of Leukocytes a. Leukopoiesis, the formation of white blood cells, is regulated by th e production of interleukins and colony-stimulating factors (CSF). b. Leukopoiesis involves differentiation of hemocytoblasts along two pathways: lymphoid and myeloid stem cells. 6. Leukocyte Disorders a. Leukopenia is an abnormally low white blood cell count. . Leukemias are clones of a single white blood cell that remain unspecialized and divide out of control. c. Infectious mononucleosis is a disease caused by the Epstein-Barr virus. C. Platelets (pp. 648–649; Fig. 17. 12) 1. Platelets are not complete cells, but fragments of large cells called megakaryocytes. 2. Platelets are critical to the clotting process, forming the temporary seal when a blood vessel breaks. 3. Formation of platelets involves repeated mitoses of megakaryocytes without cytokinesis. IV. Hemostasis (pp. 649–654; Figs. 17. 13–17. 14; Table 17. 3) A. A break in a blood vessel stimulates hemostasis, a fast, localized response to reduce blood loss through clotting (p. 649). B. Vascular spasms are the immediate vasoconstriction response to blood vessel injury (p. 649). C. Platelet Plug Formation (pp. 649–650; Fig. 17. 13) 1. When endothelium is damaged, platelets become sticky and spiky, adhering to each other and the damaged vessel wall. 2. Once attached, other platelets are attracted to the site of injury, activating a positive feedback loop for clot formation. D. Coagulation, or blood clotting, is a multistep process in which blood is transformed from a liquid to a gel (pp. 50–652; Figs. 17. 13–17. 14; Table 17. 3). 1. Factors that promote clotting are called clotting factors, or procoagulants; those that inhibit clot formation are called anticoagulants. 2. The clotting process involves three phases: formation of prothrombin activator, conversion of prothrombin to thrombin, and the formation of fibrin mesh fr om fibrinogen in the plasma. a. The intrinsic pathway of clotting is so named because all factors necessary are present within the blood. It is a slower clotting pathway, and may be triggered by negatively charged surfaces, such as activated platelets, collagen, or glass. b. The extrinsic pathway is triggered through an endothelium-derived protein factor, called tissue factor (TF) or factor III, and can occur very rapidly. E. Clot Retraction and Repair (p. 652) 1. Clot retraction is a process in which the contractile proteins within platelets contract and pull on neighboring fibrin strands, squeezing plasma from the clot and pulling damaged tissue edges together. 2. Repair is stimulated by platelet-derived growth factor (PDGF). F. Fibrinolysis removes unneeded clots through the action of the fibrin-digesting enzyme plasmin (p. 652). G. Factors Limiting Clot Growth or Formation (pp. 652–653) 1. Rapidly moving blood disseminates clotting factors before they can initiate a clotting cascade. 2. Thrombin that is not bound to fibrin is inactivated by antithrombin III and protein C, as well as heparin. H. Disorders of Hemostasis (pp. 653–654) 1. Thromboembolytic disorders result from conditions that cause undesirable clotting, such as roughening of vessel endothelium, slow-flowing blood, or blood stasis. 2. Disseminated intravascular coagulation is a situation leading to widespread clotting throughout intact vessels, and may occur as a complication of pregnancy, septicemia, or incompatible blood transfusions. . Bleeding disorders arise from abnormalities that prevent normal clot formation, such as a deficiency in circulating platelets, lack of synthesis of procoagulants, or hemophilia. V. Transfusion and Blood Replacement (pp. 654–657; Fig. 17. 15; Table 17. 4) A. Transfusion of whole blood is routine when blood loss is substantial, or when treating thrombocytopenia (pp. 654–656; Fig. 17. 15; Table 17. 4). 1. Humans have different blood types based on specific antigens on RBC membranes. 2. ABO blood groups are based on the presence or absence of two types of agglutinogens. 3. Preformed antibodies (agglutinins) are present in blood plasma and do not match the individual’s blood. 4. The Rh factor is a group of RBC antigens that are either present in Rh+ blood, or absent in Rh– blood. 5. A transfusion reaction occurs if the infused donor blood type is attacked by the recipient’s blood plasma agglutinins, resulting in agglutination and hemolysis of the donor cells. B. Plasma and blood volume expanders are given in cases of extremely low blood volume (pp. 656–657). VI. Diagnostic Blood Tests (p. 657) A. Changes in some of the visual properties of blood can signal diseases such as anemia, heart disease, and diabetes (p. 57). B. Differential white blood cell counts are used to detect differences in relative amounts of specific blood cell types (p. 657). C. Prothrombin time, which measures the amount of prothrombin in the blood, and platelet counts evaluate the status of the hemostasis system (p. 657). D. SMAC, SMA12–60, and com plete blood count (CBC) give comprehensive values of the condition of the blood (p. 657). VII. Developmental Aspects of Blood (p. 657) A. Prior to birth, blood cell formation occurs within the fetal yolk sac, liver, and spleen, but by the seventh month, red bone marrow is the primary site of hematopoiesis (p. 57). B. Fetal blood cells form hemoglobin-F, which has a higher affinity for oxygen than adult hemoglobin, hemoglobin-A (p. 657). Cross References From Chapters 1-15 Additional information on topics covered in Chapter 17 can be found in the chapters listed below. 1. Chapter 3: Diffusion; osmosis 2. Chapter 4: Tissue repair 3. Chapter 6: Hematopoietic tissue Laboratory Correlations 1. Marieb, E. N. , and S. J. Mitchell. Human Anatomy Physiology Laboratory Manual: Cat and Fetal Pig Versions. Ninth Edition Updates. Benjamin Cummings, 2009. Exercise 29: Blood PhysioExâ„ ¢ 8. Exercise 29B: Blood Analysis: Computer Simulation 2. Marieb, E. N. , and S. J. Mitchell. Human Anatomy Physiology Laboratory Manual: Main Version. Eighth Edition Update. Benjamin Cummings, 2009. Exercise 29: Blood PhysioExâ„ ¢ 8. 0 Exercise 29B: Blood Analysis: Computer Simulation Online Resources for Students myAPâ„ ¢ www. myaandp. com The following shows the organization of the Chapter Guide page in myAPâ„ ¢. The Chapter Guide organizes all the chapter-specific online media resources for Chapter 17 in one convenient location, with e-book links to each section of the textbook. Students can also access AP Flix animations, MP3 Tutor Sessions, Interactive Physiology ® 10-System Suite, Practice Anatomy Labâ„ ¢ 2. 0, PhysioExâ„ ¢ 8. 0, and much more. Objectives Section 17. 1 Overview: Blood Composition and Functions (pp. 635–636) Section 17. 2 Blood Plasma (p. 636) Memory Game: Blood Cells Section 17. 3 Formed Elements (pp. 637–649) MP3 Tutor Session: Hemoglobin: Function and Impact Interactive Physiology ® 10-System Suite: Respiratory System: Gas Transport Memory Game: Identifying the Formed Elements of Blood Case Study: Iron-Deficiency Anemia Case Study: Sickle-Cell Anemia Section 17. Hemostasis (pp. 649–654) Section 17. 5 Transfusion and Blood Replacement (pp. 654–657) Section 17. 6 Diagnostic Blood Tests (p. 657) Section 17. 7 Developmental Aspects of Blood (p. 657) Chapter Summary Crossword Puzzle 17. 1 Crossword Puzzle 17. 2 Crossword Puzzle 17. 3 Web Links Chapter Quizzes Art Labeling Quiz Matching Quiz Multiple-Choi ce Quiz True-False Quiz Chapter Practice Test Study Tools Histology Atlas myeBook Flashcards Glossary Answers to End-of-Chapter Questions Multiple-Choice and Matching Question answers appear in Appendix G of the main text. Short Answer Essay Questions 11. a. The formed elements are living blood cells. The major categories of formed elements are erythrocytes, leukocytes, and platelets. b. The least numerous of the formed elements are the leukocytes. c. The buffy coat in a hematocrit tube comprises the white blood cells and platelets. (p. 635) 12. Hemoglobin is made up of the protein globin bound to the pigment heme. Each molecule contains four polypeptide chains (globins) and four heme groups, each bearing an atom of iron in its center. Its function is to bind oxygen to each iron atom. When oxygen is loaded (bound to hemoglobin), the hemoglobin becomes bright red. When oxygen is unloaded from the iron, the hemoglobin becomes dark red. (p. 638) 13. With a high hematocrit, you would expect the hemoglobin determination to be high, since the hematocrit is the percent of blood made up of RBCs. (p. 635) 14. In addition to carbohydrates for energy and amino acids needed for protein synthesis, the nutrients needed for erythropoiesis are iron and certain B vitamins. (p. 640) 15. a. -In the process of erythropoiesis, a hemocytoblast is transformed into a proerythroblast, which gives rise to early, then late erythroblasts, normoblasts, and reticulocytes. b. The immature cell type released to the circulation is the reticulocyte. c. The reticulocyte differs from a mature erythrocyte in that it still contains some rough ER. (p. 639) 16. The physiological attributes that contribute to the function of white blood cells in the body include the ability to move by amoeboid action, exhibition of positive chemotaxis enabling them to pinpoint areas of tissue damage, diapedesis (moving through capillary walls), and the ability to participate in phagocytosis. (p. 643) 17. a. With a severe infection, the WBC count would be closest to 15,000 WBC/mm3 of blood. . This condition is called leukocytosis. (p. 643) 18. a. Platelets appear as small discoid fragments of large, multinucleated cells called megakaryocytes. They are essential for the clotting process and work by clumping together to form a temporary plug to prevent blood loss. b. Platelets should not be called â€Å"cells† because they are only fragments of cells. (p. 648) 19. a. Literally, hemostasis is â€Å"blood standing still† because it refers to clotted blood. It encompasses the steps that prevent blood loss from blood vessels. (p. 649) b. The three major steps of coagulation include the formation of prothrombin activator by a cascade of activated procoagulants, the use of prothrombin activator enzymatically to release the active enzyme thrombin from prothrombin, and the use of thrombin to cause fibrinogen to form fibrin strands. (pp. 649–652) c. The intrinsic pathway depends on substances present in (intrinsic to) blood. It has many more steps and intermediates, and is slower. The extrinsic mechanism bypasses the early steps of the intrinsic mechanism and is triggered by tissue factor (thromboplastin) released by injured cells in the vessel wall or in surrounding tissues. pp. 650–651) d. Calcium is essential to virtually all stages of coagulation. (p. 651) 20. a. Fibrinolysis is the disposal of clots when healing has occurred. b. The importance of this process is that without it, blood vessels would gradually become occluded by clots that are no longer necessary. (p. 652) 21. a. Clot overgrowth is usuall y prevented by rapid removal of coagulation factors and inhibition of activated clotting factors. (pp. 652–653) b. Two conditions that may lead to unnecessary (and undesirable) clot formation are roughening of the vessel wall endothelium and blood stasis. (p. 653) 22. Bleeding disorders occur when the liver cannot synthesize its usual supply of procoagulants. (p. 653) 23. a. A transfusion reaction involves agglutination of foreign RBCs, leading to clogging of small blood vessels, and lysis of the donated RBCs. It occurs when mismatched blood is transfused. b. Possible consequences include disruption of oxygen-carrying capacity, fever, chills, nausea, vomiting, general toxicity, and renal failure. (p. 656) 24. Among other things, poor nutrition can cause iron-deficiency anemia due to inadequate intake of iron-containing foods or to pernicious anemia due to deficiency of vitamin B12. p. 642) 25. The most common blood-related problems for the aged include chronic types of leukemias, anemias, and thromboembolytic disease. (p. 657) Critical Thinking and Clinical Application Questions 1. Hemopoiesis is a process involving fairly rapid cell production. Because chemotherapeutics simply target cells exhibiting rapid turnover (rather than other specific pro perties of cancer cells), hemopoiesis is a target of chemotherapeutic drugs and must be carefully monitored. (pp. 638–639) 2. a. The woman would probably be given a whole blood transfusion. It is essential that she maintain sufficient O2-carrying capacity to serve fetal needs and blood volume to maintain circulation. b. The blood tests that would be performed include tests for ABO and Rh group antigen and cross matching. (pp. 654–655) 3. a. Polycythemia accounts for his higher erythrocyte count because of the need to produce more RBCs to increase his O2 binding and transport ability in the high-altitude (thinner air) environment of the Alps. Enhanced production of RBCs was prompted by an increased production of erythropoietin. b. His RBC count will not stay higher than normal because the excess production of RBCs will depress erythropoietin production by the kidneys when adequate levels of O2 are being transported in the blood. (p. 643) 4. Janie’s leukocytes are immature or abnormal and are incapable of defending her body in the usual way. (p. 648) 5. Red bone marrow is the site of hemopoiesis, and if it is destroyed by benzene, hemocytoblasts will not be produced, which will reduce the production of megakaryocytes (the progenitor cells of platelets, which are involved in clotting). p. 638) 6. Tyler is turning out a high rate of reticulocytes (immature red blood cells), which accounts for his high hematocrit. (p. 639) 7. An analysis of the clotting process described in the text should reveal that the two blood proteins are thrombin and fibrinogen. (p. 650) 8. An elevated RBC count could be related to smoking, due to the frequent hypoxia that results from inhalation of oxygen-poor cigarette smoke. (p. 6 43) 9. Aspirin is a mild anticoagulant, which could cause excessive bleeding during or after surgery. (p. 653)

Research Proposal on Reading Skills Essay Example

Research Proposal on Reading Skills Essay Reading skills are the skills which are appropriate for people and say much about their intelligence. Reading is the ability to perceive and understand written or printed symbols called letters. People started writing several thousands of years ago and it was a great development of the human civilization and the revolution in the development of knowledge. When people started to record facts about their life and develop different genres of literature, the necessity of being able to read became really urgent. With the run of time people wrote and printed more and more books and the role of a book became really great. For several centuries the book has been the symbol of wisdom and knowledge. Today every child is taught to read, because without reading he will not manage to live in the human society and achieve something in life. Reading touches upon everything people do. Education, health care, art, law, business, finance, engineering, etc. – everything requires well-developed reading skills. Reading skills appear during the long process of teaching and practice. Children have to read much, especially aloud, to be able to read fast and remember the read information. There are special methods which make the process of teaching reading skills faster and more effective. Special techniques enable one read the whole page for a few seconds and remember the whole data. There are courses which teach people to master such skills. We will write a custom essay sample on Research Proposal on Reading Skills specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Research Proposal on Reading Skills specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Research Proposal on Reading Skills specifically for you FOR ONLY $16.38 $13.9/page Hire Writer Reading skills influence the general level of human knowledge and intelligence, so children should be taught reading from the early yearly years. A student who has the task to prepare a good research proposal will need to devote much time to the investigation of the topic to understand the nature and aspects of reading, factors which influence reading. When one understands the general points related with reading, he will be able to create his own methods effective for teaching reading skills. If the methods are useful enough, the research proposal can be considered a successful one and will convince the teacher in the importance of the topic. Very often students face a great number of problems when start writing their research proposals and no wonder, because one should organize an interesting and informative paper and persuade the professor that the chosen topic is worth investigation. The web can help students prepare good papers themselves due to the existence of the free example research proposals on reading skills, which possess proper composition and way of conducting the analysis. It is quite easy to find a well-organized free sample research proposal which can help you organize your thoughts in a good way and make proper structure for your paper, which will illustrate your professional skills. *** NOTE! As far as you know free sample research proposals and examples about Reading are 100% plagiarized!!! At EssayLib.com writing service you can order a custom research proposal on Reading Skills topics. Your research paper proposal will be written from scratch. We hire top-rated Ph.D. and Master’s writers only to provide students with professional research proposal help at affordable rates. Each customer will get a non-plagiarized paper with timely delivery. Just visit our website and fill in the order form with all proposal details: Enjoy our professional research proposal writing service!

Air Quality Essays - Aerosols, Air Pollution, Free Essays

Air Quality Essays - Aerosols, Air Pollution, Free Essays Air Quality Air Quality & Dispersion Today, the air quality aspect of ARL research is by far the dominant theme, but distinctions among the themes remain somewhat vague. For example, the models developed for emergency response purposes are among those used for air quality prediction. The Air Quality and Dispersion theme is one of the strongest ties that binds ARL's components together. ARL is not heavily involved in the pure science of the business. Instead, ARL focusses on the need to assemble integrated understanding and models from all available sources, to develop the capability to predict changes in air quality that will follow changes in emissions, or that will occur as a result of meteorological factors. ARL air quality research extends to studies of atmospheric deposition essentially the coupling between the atmospheric pollutant environment and the surface below. ARL now operates the only research-grade deposition monitoring network in the nation: AIRMoN (the Atmospheric Integrated Research Monitoring Network). Programs. Air Quality and Deposition Modeling Air quality models have demanded this kind of coupling for a considerable time. As a result, there are now well-developed descriptions of PBL processes in use in air quality models. ARL research products are now receiving a wider audience, within the mesoscale modeling community at large. It is recognized that modern models are invariably data assimilative, and that modern monitoring programs require coupled modeling activities for data interpretation. Model development programs are supported by a vigorous physical modeling program, located at Research Triangle Park, NC. ARL operates one of the nation's major fluid modeling facilities, at which studies are conducted on the effects of mountains, buildings, and other surface obstacles on atmospheric flow patterns. Integrated Monitoring, and AIRMoN The Atmospheric Integrated Research Monitoring Network is an atmospheric component to the overall national integrated monitoring initiative that is currently evolving. AIRMoN has two principal components: wet and dry deposition. ARL presently focuses its research attention on the measurement of precipitation chemistry with fine time resolution (AIRMoN-wet), the development of systems for measuring deposition, both wet and dry, the measurement of dry deposition using micrometeorological methods (AIRMoN-dry), the development of techniques for assessing air-surface exchange in areas (such as specific watersheds) where intensive studies are not feasible, and the extension of local measurements and knowledge to describe areal average exchange in numerical models. Aerosols and visibility ARL specializes in the geochemical cycling of atmospheric aerosols, particularly the particulate component. Research groups in ARL concentrate on (a) the injection of dust and soil particles into the atmosphere, (b) the transport of particles through the atmosphere, the production of aerosol particles in the air by chemical reactions, (d) the scavenging of airborne particles by clouds and their subsequent deposition in precipitation, (e) the dry deposition of particles as air moves across different landscapes, and (f) the assembly of numerical models. Specific topics include the injection of dust and soil particles into the atmosphere, the long-range transport of particles through the atmosphere, the production of aerosol particles in the air by chemical reactions, the scavenging of airborne particles by clouds and their subsequent deposition in precipitation, and the dry deposition of particles as air moves across different landscapes. International ARL serves as the leader of the U.S. multi-agency effort to impose formalized and uniform quality assurance programs on the many national air quality and deposition monitoring networks that are operational around the globe. How are ozone concentrations calculated with Hysplit? Ozone is then calculated from the photostationary state equation. The IER solution is used in the operational Hysplit ozone calculation. The pollutant particles are tracked and air concentrations for each species are computed each advection time step following the usual lagrangian approaches. At the conclusion of the advection step the GRS differential equations are solved on the concentration grid (Eulerian solution), and the change of concentration of each pollutant species is applied to the pollutant mass on the particles that contributed concentration to each grid cell. -Eulerian chemistry solution on the grid dc/dt = Equations 1 - 7} 1) ROC + hv -* RP + ROC Nitric oxide-ozone titration reaction 5) RP + RP -* RP k5 = 10200 Sink for nitrogen dioxide to stable gaseous nitrates

Francis Bacon on Youth and Age

Francis Bacon on Youth and Age Francis Bacon  was a true Renaissance man- statesman, writer, and philosopher  of science. He is considered the first major English essayist. Professor Brian Vickers has pointed out that Bacon could vary the tempo of argument in order to highlight important aspects. In the essay Of Youth and Age, Vickers notes in the introduction to the Oxford Worlds Classics 1999 edition of The Essays Or Counsels, Civil and Moral  that Bacon uses a most effective variation in tempo, now slowing down, now speeding up, together with syntactical parallelism, in order to characterize the two opposed stages of life.   Of Youth and Age A man that is young in years may be old in ​hours, if he have lost no time. But that happeneth rarely. Generally, youth is like the first cogitations, not so wise as the second. For there is a youth in thoughts, as well as in ages. And yet the invention of young men is more lively than that of old, and imaginations stream into their minds better, and as it were more divinely. Natures that have much heat and great and violent desires and perturbations, are not ripe for action till they have passed the meridian of their years; as it was with Julius Caesar, and Septimius Severus. Of the latter of whom it is said, Juventutem egit erroribus, imo furoribus, plenum1. And yet he was the ablest emperor, almost, of all the list. But reposed natures may do well in youth. As it is seen in Augustus Caesar, Cosmus Duke of Florence, Gaston de Foix, and others. On the other side, heat and vivacity in age is an excellent composition for business. Young men are fitter to invent than to judge; f itter for execution than for counsel; and fitter for new projects than for settled business. For the experience of age, in things that fall within the compass of it, directeth them; but in new things, abuseth them. The errors of young men are the ruin of business; but the errors of aged men amount but to this, that more might have been done, or sooner. Young men, in the conduct and manage of actions, embrace more than they can hold; stir more than they can quiet; fly to the end, without consideration of the means and degrees; pursue some few principles which they have chanced upon absurdly; care not to innovate, which draws unknown inconveniences; use extreme remedies at first; and that which doubleth all errors, will not acknowledge or retract them; like an unready horse, that will neither stop nor turn. Men of age object too much, consult too long, adventure too little, repent too soon, and seldom drive business home to the full period, but content themselves with a mediocrity of success. Certainly it is good to compound employments of both; for that will be good for the present, because the virtues of either age may correct the defects of both; and good for succession, that young men may be learners, while men in age are actors; and, lastly, good for extern accidents, because authority followeth old men, and favour and popularit y youth. But for the moral part, perhaps youth will have the pre-eminence, as age hath for the politic. A certain rabbin, upon the text, Your young men shall see visions, and your old men shall dream dreams, inferreth that young men are admitted nearer to God than old, because vision is a clearer revelation than a dream. And certainly, the more a man drinketh of the world, the more it intoxicateth; and age doth profit rather in the powers of understanding, than in the virtues of the will and affections. There be some have an over-early ripeness in their years, which fadeth betimes. These are, first, such as have brittle wits, the edge whereof is soon turned; such as was Hermogenes the rhetorician, whose books are exceeding subtle; who afterwards waxed stupid. A second sort is of those that have some natural dispositions which have better grace in youth than in age; such as is a fluent and luxuriant speech, which becomes youth well, but not age: so Tully saith of Hortensius, Idem manebat, neq ue idem decebat2. The third is of such as take too high a strain at the first, and are magnanimous more than tract of years can uphold. As was Scipio Africanus, of whom Livy saith in effect, Ultima primis cedebant3. 1 He passed a youth full of errors, yea of madnesses.2 He continued the same, when the same was not becoming.3 His last actions were not equal to his first.

Civilization Essay Example | Topics and Well Written Essays - 1500 words

Civilization - Essay Example Industrialization started with the mass production of pottery, textiles and metal tools. Writing emerged as a means of communication invented mainly to deal with urban problems of management and book keeping. On the social front, people were grouped into classes based on control of resources, wealth, political authority, family, or religion. By 3000 B.C.E., the Sumerians in south Babylonia (Southern Mesopotamia) founded the oldest cities of Ur, Nippur, and Uruk; the largest city in the world. Quarrels over water and agricultural land led to increased warfare to create kingdoms ruling several city states. The city of Kish in north Babylonia had the first king in history. In the far east of Babylonia, the Akkadians established the first empire in history in the city of Akkade. Sargon, their first king who was the servant of the king of Kish became the first conqueror of history. His grandson, Naram-Sin developed unheard-of wealth and power that he declared himself god and built temples to himself. In 2125 B.C.E., the Sumerians established the third dynasty empire on the foundation of the Akkadian empire. In 1792 B.C.E. King Hammurabi created a kingdom to embrace most of Mesopotamia. At 1600 B.C.E., the Babylonian kingdom fell apart by invasions from the Hittites, Hurrians, and Kassites. Ingredients of civilization were ... Their language consisted of thousands of characters that represented words and some sounds. In ancient Egypt, the hieroglyphics language was invented to involve hundreds of picture signs, each representing one, two or three sounds to mean a word or category. Text was written horizontally from right to left or left to right, or vertically from top to bottom in both horizontal directions. Another ingredient of culture is social change. In ancient Egypt, black Africans from Nubia and Asians from the east were captured in war and brought back to Egypt as slaves. Sometimes entire people were slaved as the Hebrews according to the Bible. Slaves performed domestic services, labored in fields with the peasants, worked as policemen or soldiers as they also labored to erect the great temples and monuments of Egypt. They could be freed by in most occasions they were not. In Mesopotamia there were two main types of slavery: chattel and debt slavery. Chattel slaves were bought like property and had no legal rights as they were easily recognized by their hair style or tattoo on their arm. They were non-Mesopotamians bought from slave merchants or imprisoned during war. Chattel slaves were mainly used in domestic services rather than fieldwork. Debt slave were more common than chattel slaves. They were declared slaves when members of family were declared as surety of a loan where they have to labor to pay the interest on the loan. They could not be sold and they are redeemed free once the debt is paid off. However slaves had little legal protection and could buy his or her freedom. Hammurabi's Law Code revealed the classes of people of nobles, commoners, and slaves, who were not treated equally. Women in Mesopotamia could

Virtual Working Teams Essay Example | Topics and Well Written Essays - 500 words - 1

Virtual Working Teams - Essay Example Peru is highly collectivist, in which decision-making is trusted and valued with group emphasis (geert-hofstede.com, 2). France is highly individualistic, valuing rewards and recognition for individual accomplishment of that of group affiliation and group-based norms (geert-hofstede.com, 2); the same is true for the United States. Egyptian protocols are highly social even in the business environment (Dunn, 1). As part of expatriate training, managers will be provided exceptional literature on cultural dimensions to assist in locating top talent for the virtual team role in each geographical region. Training will consist of literature and software scenarios based on customer relationship management principles and corporate social responsibility related to government interaction and business leadership. Training will further consist of inter-dependent group methodologies in the form of role play exercises to highlight scenario responses in a virtual environment. Skype and other streaming software will assist in this development with the HR manager in the U.S. who will observe and recommend solutions based on testing scores and expatriate management assessment. For issues of cost reduction, cloud computing will be the majority of software support. This system provides access to CRM software over the Internet with pay-per-use access (Burns, 11). This will avoid the need for a defined, individualized information technology support system. Communications between teams will occur via existing e-mail systems (i.e. Lotus Notes), streaming video, and teleconferencing. These are effective systems for real-time project communications. However, a recent study using a sample of 42 interviewed virtual team members from 26 different organizations indicated that face-to-face discussion is required in order to gain commitment and build productivity (Dube & Robey, 18). To facilitate this need, key personnel

Mathematics, the Connection Between Art and Science Essay Example for Free

Mathematics, the Connection Between Art and Science Essay Although there are many differences that set art and science apart, they share one undeniable commonality. This bond that is present between what is otherwise considered as polar opposites is mathematics. As shown in Professor Vesna’s lecture, mathematics is imperative to the development of art. Through math, artists have come to understand perspective, proportion, and geometrics. In terms of science, mathematics is the foundation which every theory stands upon. Nature, humans, and the digital world would have been impossible to comprehend without numbers to bridge the gap between the unknown and the understood. Truly, mathematics is ubiquitous and continues to prove its importance to this day. A novel amalgamation that consists of mathematics, art, and science is music. Milkman, an artist of the mash-up genre, is a musician that samples different songs and digitally combines them to form a brand new track. In a way, his work is described as an example of cross synthesis or convultion which according to Burk is some aspect of one sound superimposed on another. To harmoniously combine two different songs, one must fully understand every possible correlation in terms of rhythm, melody, and lyrics. And with mathematics and science making the technology available, the art of mashing up songs has become readily accessible and requires only creativity to create the next hit single. Mathematics has almost an infinite range of applications in society today. For example, Robert Lang presents mathematics as part of the core that drives origami, the art of folding paper. Lang shows that complexity is irrelevant; with mathematics to dictate origami, anything can be shaped. Because of its practicality of compacting large things, origami is used in various sectors of science which include telescope lens packing and heart stents. Another example of math’s prevalence is Theo Jansen’s presentation on his kinetic sculptures. His biological art, able to move independently, essentially redefines the wheel. Not only is it artistic but also it is a masterpiece of engineering; just a simple push can propel a massively heavy structure across difficult terrain. It is evident that math not only facilitates the evolution of artistic creations but also helps apply them as potential solutions to problems of today.