Water Is An Important Factor That Affects Sorption

Water is an important factor that affects sorption because when there is excess water or when water drains through soil from sources at the surface, adsorbed pesticide molecules can become unattached, or desorbed, and wash away to a new location (Rao, 1999). Just as degradation has a measure in the half-life of a compound, sorption also has a measure in the partition coefficient (Koc), which is a ratio of pesticide concentration in a soil bound state versus dissolved in soil-water (Rao, 1999). In fact, â€Å"the solubility of a pesticide and its sorption on soil are inversely related; [in other words], increased solubility results in less sorption† (Rao, 1999). Both sorption and degradation are effected by soil type and pH, both of which†¦show more content†¦Volatilization is a means of major pesticide loss and its rate of loss can often exceeds that of degradation, runoff, or leaching (van der Werf, 1996). For example, in an Oregon study, soil samples 64km from any a griculture were found to have DDT residues, and in Saskatchewan, Canada, 20% of 2, 4-D iso-octyl ester volatilized in 24 hours (Pimentel, 1995). Once in the atmosphere, pesticide residues can spread anywhere, even Antarctica (Pimentel, 1995). Large amounts of pesticides and organic compounds can be transported around the globe in the atmosphere, for example, â€Å"in the atmosphere of the Netherlands, the amounts of BHC, DDT, and heptachlor were reported to be 4600, 1064, and 190 pg/m 3, respectively† (Pimentel, 1995). Topography and Geology Topography and geology affect pesticide movement in as much as directing or transporting pesticides. Topography is very obvious, for example, if a field is right next to a river, it is much more likely for runoff to get into the river system, or if a field is in a low area not very far above the water table, pesticides are very likely to leach into the groundwater. On the other hand, a field could be high and dry and very far from any river or groundwater, but if it is hilly that can pose its own problems. As T. Y. Tong and Chen point out, surface runoff is an important source of non-point pollution (Tong and Chen, 2002). Though it was pointed out by van der Werf that volatilization is the biggest source of

Guide to the Upper Paleolithic

The Upper Paleolithic (ca 40,000-10,000 years BP) was a period of great transition in the world. The Neanderthals in Europe became edged out and disappeared by 33,000 years ago, and modern humans began to have the world to themselves. While the notion of a creative explosion has given way to a recognition of a long history of the development of human behaviors long before we humans left Africa, there is no doubt that things really got cooking during the UP. Timeline of the Upper Paleolithic In Europe, it is traditional to split the Upper Paleolithic into five overlapping and somewhat regional variants, based on differences between stone and bone tool assemblages. Chatelperronian (~40,000-34,000 BP) Aurignacian (~45,000-29,000 BP) Gravettian/Upper Perigordian (29,000-22,000)Solutrean (22,000-18,000 BP)Magdalenian (17,000-11,000 BP) Azilian/Federmesser (13,000-11,000 BP) Tools of the Upper Paleolithic Stone tools of the Upper Paleolithic were primarily blade-based technology. Blades are stone pieces that are twice as long as they are wide  and, generally, have parallel sides. They were used to create an astonishing range of formal tools, tools created to specific, wide-spread patterns with specific purposes. In addition, bone, antler, shell and wood were used to a great degree for both artistic and working tool types, including the first eyed needles presumably for making clothing about 21,000 years ago. The UP is perhaps best known for the cave art, wall paintings and engravings of animals and abstractions at caves such as Altamira, Lascaux, and Coa. Another development during the UP is mobiliary art (basically, mobiliary art is that which can be carried), including the famous Venus figurines and sculpted batons of antler and bone carved with representations of animals. Upper Paleolithic Lifestyles People living during the Upper Paleolithic lived in houses, some built of mammoth bone, but most huts with semi-subterranean (dugout) floors, hearths, and windbreaks. Hunting became specialized, and sophisticated planning is shown by the culling of animals, selective choices by season, and selective butchery: the first hunter-gatherer economy. Occasional mass animal killings suggest that in some places and at some times, food storage was practiced. Some evidence (different site types and the so-called schlep effect) suggest that small groups of people went on hunting trips and returned with meat to the base camps. The first domesticated animal appears during the Upper Paleolithic: the dog, companion to us humans for over 15,000 years. Colonization during the UP Humans colonized Australia and the Americas by the end of the Upper Paleolithic  and moved into hitherto unexploited regions such as deserts and tundras. The End of the Upper Paleolithic The end of the UP came about because of climate change: global warming, which affected humanitys ability to fend for itself. Archaeologists have called that period of adjustment the Azilian. Upper Paleolithic Sites See Upper Paleolithic Sites in Europe Israel: Qafzeh Cave, Ohalo II Egypt: Nazlet Khater Morocco: Grotte des Pigeons Australia: Lake Mungo, Devils Lair, Willandra Lakes Japan: Sunagawa Georgia: Dzudzuana Cave China: Yuchanyan Cave Americas Daisy Cave, Monte Verde Sources See specific sites and issues for additional references. Cunliffe, Barry. 1998. Prehistoric Europe: An Illustrated History. Oxford University Press, Oxford. Fagan, Brian (editor). 1996 The Oxford Companion to Archaeology, Brian Fagan. Oxford University Press, Oxford.

The Aging Special Senses Free Essays

Vanessa McClain Anatomy and Physiology GE 258 Unit 9. Assignment 2. The Aging Special Senses Thursday, November 17, 2011 1. We will write a custom essay sample on The Aging Special Senses or any similar topic only for you Order Now ) Age-related Macular Disease – Is a disease associated with aging that gradually destroys sharp, central vision. Central vision is needed for seeing objects clearly and for common daily tasks such as reading and driving. AMD affects the macula, the part of the eye that allows you to see fine detail. There are two forms of age-related macular degeneration: Dry form and Wet form. The dry form is characterized by the presence of yellow deposits, called drusen, in the macula. A few drusen may not cause change in vision; however, as they grow in size and increase in number, they may lead to a dimming or distortion of vision that people find most noticeable when they read. In more advanced stages, there is also a thinning of the light-sensitive layer of cells in the macula leading to atrophy, or tissue death. In the atrophic form, patients may have blind spots in the center of their vision. The wet form is characterized by the growth of abnormal blood vessels from the choroid underneath the macula. These blood vessels leak blood and fluid into the retina, causing distortion of vision that makes straight lines look wavy, as well as blind spots and loss of central vision. They eventually scar, leading to permanent loss of central vision. They affect daily life in that there is struggle to do housework, studying, shopping, enjoying leisure activities and interests such as reading. 2. ) Glaucoma – Is a disease in which damage to the optic nerve leads to progressive, irreversible vision loss because the aqueous humor does not flow out of the eye properly and fluid pressure builds up over time causing damage to the optic nerve. It is the second leading cause of blindness. It affects one’s daily life such as driving or playing certain sports . It causes contrast sensitivity, problems with glare, and light sensitivity which interfere with daily activities. 3. ) Cataracts – Are cloudy areas in the lens inside the eye which is normally clear. There are two types: Age related cataracts which appear later in life and congenital cataracts, that may be present when a baby is born or shortly after birth. Cataracts cause an individual to see halos around lights. In some, the glare from car ights become bothersome and driving at night may be dangerous. Although far sight is affected more than near vision. If the cataracts are bad enough, it can make reading more difficult as well. 4. ) Detached Retina – Is a disorder of the eye in which the retina peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, l eading to vision loss and blindness. It affects daily activities because of the sudden appearance of â€Å"floaters†, (dark, semi-transparent, floating shapes) in the field of vision or a shower of black dots. These are actually red blood cells because all retinal tears bleed a little when they occur. ) It causes a loss of central vision, a loss of peripheral vision called the â€Å"curtain effect† and brief, bright flashes of light which may be most noticeable when you move your eyes in the dark. 5. ) Deafness (sensorineural and conductive) – Sensorineural hearing loss is due to damage to the pathway that sound impulses take from the hair cells of the inner ear to the auditory nerve and the brain. Conductive hearing loss is caused by anything that interferes with the transmission of sound from the outer to the inner ear. Both of these hearing losses affect daily life because you may experience difficulty localizing sounds or understanding speech in busy environments and participating in everyday normal conversations which can lead to social isolation, frustration, tension, anger, stress and depression. 6. ) Meniere’s Disease – Is a disorder of the inner ear that can affect hearing and balance to a varying degree. It is characterized by episodes of vertigo and tinnitus and progressive hearing loss, though usually in one ear. It affects daily life because for some, sounds appear tiny or distorted and may experience unusual sensitivity to noises. In addition, you may experience a sensation of fullness or pressure in one or both ears and unilateral or bilateral tinnitus. Some may have parasitic symptoms, which aren’t necessarily symptoms of Meniere’s, but rather side effects from other symptoms. Typically these are nausea, vomiting and sweating. 7. ) Ataxia – Is an inability to coordinate muscle activity during voluntary movement, most often results from disorders of the cerebellum or the posterior columns of the spinal cord; may involve the limbs, head or trunk. Affects one’s daily life because it can alter a person’s walking pattern. For e. . wide based unsteady gain with difficulty stopping, turning and problem walking in poorly lit areas. It can cause falls due to postural instability, difficulty with tasks requiring fine control and coordination, tremors during voluntary movement, slurred speech and altered handwriting. 8. ) Hyposomnia – literally means â€Å"less† sleep. I t is a condition whereby a person does not need as much sleep as a normal individual. Specifically, they sleep less than 6 hours per night, but are adequately rested. It may occur at the onset, during or at the termination of sleep, and is common among the elderly. It affects daily life because the person that sleeps less but feels they need more experience the same problems as the person with insomnia that cannot sleep more than a few hours but feel they need more. It affects everyday life and activities because it is usually accompanied by general emotional upset, depression, or anxiety. References Conductive and Sensorineural hearing loss | Hearing Aid Know. (n. d. ). Hearing aids – hearing loss – help, information and blog – hear aids | Hearing Aid Know. Retrieved November 13, 2011, from http://www. hearingaidknow. om/2007/10/25/conductive-and-sensorineural-hearing-loss/ Detached Retina (or Retinal Detachment): Eye Conditions: Patient Care: U-M Kellogg Eye Center. (n. d. ). University of Michigan Kellogg Eye Center in Ann Arbor, Michigan. Retrieved November 13, 2011, from http://www. kellogg. umich. edu/patientcare/conditions/detached. retina. html Manan Hearing Care | Types of Hearing Loss. (n. d. ). Manan Hearing Care | #1 Midwest On-Site Hearing Care. Retrieved November 13, 2011, from http://mananhearing. com/types_of_hearing_loss. html Meniere’s disease – MayoClinic. com. (n. d. ). Mayo Clinic. Retrieved November 13, 2011, from http://www. mayoclinic. com/health/menieres-disease/DS00535 What is Cataracts?. (n. d. ). Consumer Reports: Expert product reviews and product Ratings from our test labs. Retrieved November 13, 2011, from http://www. consumerreports. org/health/conditions-and-treatments/cataracts/what-is-it. htm What is Glaucoma? | Glaucoma Research Foundation. (n. d. ). Glaucoma Research Foundation. Retrieved November 13, 2011, from http://www. glaucoma. org/glaucoma/what-is-glaucoma. php? gclid=CO2f2Jvns6wCFY3KKgodyH2rIQ hyposomnia (thing)@Everything2. com. (n. d. ). Everything2. Retrieved November 13, 2011, from How to cite The Aging Special Senses, Papers

Fires of Jubilee Nat Turners Fierce Rebellion free essay sample

This paper discusses Stephen Oats book `Fires of Jubilee: Nat Turners Fierce Rebellion. This paper takes a look at a slave uprising as documented in Stephen Oats book Fires of Jubilee: Nat Turners Fierce Rebellion. It analyzes the main character of the book, Nat Turner and how his seemingly small scale revolution set the wheels in motion for the eventual abolishment of slavery. From the paper: Stephen Oates, in his book Fires of Jubilee: Nat Turners Fierce Rebellion, crafts a compelling story. The story of this slave rebellion is indeed so compelling a one that it would be hard to imagine a telling of it that was not fascinating. But in the end Oates, despite his credentials, does a disservice both to Turner and to the larger forces at work in the decades before the Civil War. In order to assess Oatess treatment of Turner, it would be useful to examine what is generally known and agreed to about Turner. We will write a custom essay sample on Fires of Jubilee: Nat Turners Fierce Rebellion or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page He was born on a plantation in Southampton County, Virginia, in 1800 and was from a very early age a popular religious leader among his fellow slaves. In part due no doubt to whatever had motivated him to become interested in preaching and in part because he was so popular with other slaves who came to listen to him talk about God, Turner became convinced that he had been chosen by God to lead his people to freedom.`