Robert Gould Shaw Led Unions First Black Regiment

The son of prominent Boston abolitionists, Robert Gould Shaw was born October 10, 1837, to Francis and Sara Shaw. The heir to a large fortune, Francis Shaw advocated for a variety of causes and Robert was raised in an environment that included notable personalities such as William Lloyd Garrison, Charles Sumner, Nathaniel Hawthorne, and Ralph Waldo Emerson. In 1846, the family moved to Staten Island, NY and, despite being Unitarian, Robert  enrolled in St. Johns College Roman Catholic School. Five years later, the Shaws traveled to Europe and Robert continued his studies abroad. Education and First Job Returning home in 1855, he enrolled at Harvard the following year. After three years of university, Shaw withdrew from Harvard in order to take a position in his uncles, Henry P. Sturgis, mercantile firm in New York. Though he was fond of the city, he found that he was ill-suited for business. While his interest in his work waned, he developed a passion for politics. A supporter of Abraham Lincoln, Shaw hoped that the ensuing secession crisis would see the Southern states brought back by force or cut loose from the United States. Early Civil War With the secession crisis peaking, Shaw enlisted in the 7th New York State Militia with the hope that he would see action if war broke out. Following the attack on Fort Sumter, the 7th NYS responded to Lincolns call for 75,000 volunteers to put down the rebellion. Traveling to Washington, the regiment was quartered in the Capitol. While in the city, Shaw had the opportunity to meet both Secretary of State William Seward and President Lincoln. As the 7th NYS was only a short-term regiment, Shaw, who wished to remain in the service, applied for a permanent commission in a Massachusetts regiment. On May 11, 1861, his request was granted and he was commissioned as a second lieutenant in the 2nd Massachusetts Infantry. Returning north, Shaw joined the regiment at Camp Andrew in West Roxbury for training. In July, the regiment was sent to Martinsburg, VA, and soon joined Major General Nathaniel Banks corps. Over the next year, Shaw served in western Maryland and Virginia, with the regiment taking part in attempts to stop Major General Thomas Stonewall Jacksons campaign in the Shenandoah Valley. During the First Battle of Winchester, Shaw luckily avoided being wounded when a bullet hit his pocket watch. A short time later, Shaw was offered a position on Brigadier General George H. Gordons staff which he accepted. After taking part in the Battle of Cedar Mountain on August 9, 1862, Shaw was promoted to captain. While the 2nd Massachusetts brigade was present at the Battle of Second Manassas later that month, it was held in reserve and did not see action. On September 17, Gordons brigade saw heavy combat in the East Woods during the Battle of Antietam. The 54th Massachusetts Regiment On February 2, 1863, Shaws father received a letter from Massachusetts governor John A. Andrew offering Robert command of the first black regiment raised in the North, the 54th Massachusetts. Francis traveled to Virginia and presented the offer to his son. While initially reluctant, Robert was ultimately persuaded by his family to accept. Arriving in Boston on February 15, Shaw began recruiting in earnest. Assisted by Lt. Colonel Norwood Hallowell, the regiment began training at Camp Meigs. Though originally skeptical about the fighting qualities of the regiment, the mens dedication and devotion impressed him. Officially promoted to colonel on April 17, 1863, Shaw married his sweetheart Anna Kneeland Haggerty in New York on May 2. On May 28, the regiment marched through Boston, to the cheers of a massive crowd, and began their voyage south. Arriving at Hilton Head, SC on June 3, the regiment began service in Major General David Hunters Department of the South. A week after landing, the 54th took part in Colonel James Montgomerys attack on Darien, GA. The raid angered Shaw as Montgomery ordered the town looted and burned. Unwilling to take part, Shaw and the 54th largely stood and watched as events unfolded. Angered by Montgomerys actions, Shaw wrote to Gov. Andrew and the adjutant general of the department. On June 30, Shaw learned that his troops were to be paid less than white soldiers. Displeased by this, Shaw inspired his men to boycott their pay until the situation was resolved (it took 18 months). Following Shaws letters of complaint regarding the Darien raid, Hunter was relieved and replaced with Major General Quincy Gillmore. Seeking to attack Charleston, Gillmore began operations against Morris Island. These initially went well, however the 54th was excluded much to Shaws chagrin. Finally on July 16, the 54th saw action on nearby James Island when it aided in repulsing a Confederate attack. The regiment fought well and proved that black soldiers were the equals of whites. Following this action, Gillmore planned an attack on Fort Wagner on Morris Island. The honor of the lead position in the assault was given to the 54th. On the evening of July 18, believing that he would not survive the attack, Shaw sought out Edward L. Pierce, a reporter with the New York Daily Tribune, and gave him several letters and personal papers. He then returned to the regiment which was formed up for the assault. Marching over open beach, the 54th came under heavy fire from the Confederate defenders as it approached the fort. With the regiment wavering, Shaw sprung to the front yelling Forward 54th! and led his men as they charged. Surging through ditch surrounding the fort, the 54th scaled the walls. Reaching the top of the parapet, Shaw stood and waved his men forward. As he urged them on he was shot through the heart and killed. Despite the regiments valor the attack was repulsed with the 54th suffering 272 casualties (45% of its total strength). Angered by the use of black soldiers, the Confederates stripped Shaws body and buried it with his men, believing that it would humiliate his memory. After attempts by Gillmore to recover Shaws body failed, Francis Shaw asked him to stop, believing his son would prefer to rest with his men.

Essay on Cystic Fibrosis - 1025 Words

Cystic Fibrosis is a disorder where the exocrine glands secrete abnormally thick mucus, leading to obstruction of the pancreas and chronic infections of the lungs, which usually cause death in childhood or early adulthood. Some mildly affected patients may survive longer. Doctors can diagnose the disease by testing the patients perspiration because people with Cystic Fibrosis have high amounts of salt in their perspiration. Those with respiratory infections are treated with antibiotics, with aerosols that relieve constriction of the airways and liquefy the thick mucus, and by physical therapy to help patients cough up the obstructing secretions. Patients with pancreatic insufficiency can take pancreatic enzymes with meals.†¦show more content†¦The sickle-shaped red cells interfere with normal blood flow by plugging up small blood vessels. Sickle-cell anemia occurs when an individual inherits a sickle-cell gene from each parent. Programs have been initiated to detect carriers, who do not themselves show the trait; such carriers are informed that a child resulting from the union of two carriers runs a one in four risk of having sickle-cell disease. Therapy for sickle-cell anemia is largely symptomatic. Preventive administration of penicillin to affected children by the age of four months greatly decreases mortality from infections. For this reason, routine screening of newborns for sickle-cell anemia is currently carried out in more than 40 states within the United States. Down Syndrome Down Syndrome, which used to be called mongolism, is a congenital malformation accompanied by moderate to severe mental retardation, is caused by a chromosomal abnormality. People with Down syndrome are often short in height and have a small, round head with a high, flattened forehead and split, dry lips and tongue. A typical feature is a fold of skin, the epicanthic fold, on either side of the bridge of the nose. The palms show a single transverse crease and the soles have a straight crease from the heel to the space between the first and second toes. These people are also subject to congenital heart defects and tend to develop leukemia. TheirShow MoreRelatedCystic Fibrosis983 Words   |  4 Pages Can viruses used as vectors in the process of gene therapy be an effective treatment for Cystic Fibrosis? Firstly, Cystic Fibrosis is a genetic and recessive disease that mostly affects the lungs and pancreas. This leads to phlegm accumulation, salty sweat, male infertility, shortness of breath and increased risk of infection, which all contribute to premature death (CFF, 2017). Since it is recessive, you need two copies of the gene to manifest the disease, but 1/30 Americans have at least one copyRead MoreA Report On Cystic Fibrosis945 Words   |  4 PagesCystic Fibrosis Cystic fibrosis is described as a â€Å"congenital disorder affecting exocrine gland function, with respiratory effects, including excessive secretions, obstruction of the bronchial system, infection, and tissue damage† (Kowalczyk, 2014). Cystic fibrosis is also known as CF, and is the most common lethal disease in white children (Kowalczyk, 2014). People whom have CF have â€Å"histologically† normal lungs at birth. Lung damage occurs when secretions from the enlarged bronchial glands graduallyRead More Cystic Fibrosis Essay1129 Words   |  5 Pages Cystic Fibrosis is a severe hereditary disease that infects the lungs, digestive system, sweat glands and male fertility. The name Cystic Fibrosis derives from the Fibrous scar tissue that develops in the pancreas. First recognized in 1938, cystic fibrosis is generalized as an autosomal recessive disorder of the exocrine glands. About one in every 2500 Caucasians is affected, and one in 25 is a carrier of the cystic fibrosis gene. Cystic fibrosis is the most common fatal hereditaryRead MoreEssay on Cystic Fibrosis1790 Words   |  8 Pagesperson with Cystic Fibrosis. Cystic Fibrosis is a disease that forces a person to drown in mucus that fills their lungs while it wreaks havoc on the body. This chronic disease causes devastating health problems, has no cure, and forces patients to endure painful temporary treatments. Taking daily medications, maintaining a social life, and staying moderately healthy are a constant struggle for people with Cystic Fibrosis. Unlike many of the diseases that plague people today Cystic Fibrosis is givenRead MoreEssay on Cystic Fibrosis1134 Words   |  5 PagesCystic Fibrosis Cystic fibrosis is the most common lethal inherited disease, affecting about 30,000 patients worldwide. In the past decade, strides in patient management and the development of new pharmacological agents, coupled with scientific and technological advances, have increased the mean life expectancy of CF patients to approximately 30 years of age (approximately 50% of CF patients live to the age of 30). As early as 30 years ago, the median survival age was 8 years. ChronicRead MoreWhat is Cystic Fibrosis?903 Words   |  4 PagesCystic fibrosis is an autosomal recessive genetic disorder characterised by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) protein which acts as a chlorine channel that regulates water and ion levels across the epithelia. Cystic fibrosis can affect sweat glands, the respiratory system, digestive system and the reproductive system. In the lungs defects in the CFTR protein results in airway surface liquid depletion, triggering a cascade of events resulting in infectionRead MoreA Study On Cystic Fibrosis1042 Words   |  5 PagesCystic fibrosis is due to a mutation in the gene that encodes cystic fibrosis transmembrane conductance regulator (CFTR) protein. It effects the exocrine glands which are responsible for making mucus and sweat. It causes a thickening of the mucus in your body and increases the salt content of your sweat. These can lead to problems including problems absorbing oxygen, lung infections, inhibit digestive enzymes from reaching your small intestine, dehydration, increased heart rate, lower blood pressureRead MoreCystic Fibrosis : A Defect3451 Words   |  14 PagesRunning head: Cystic Fibrosis: A Defect in the CFTR Gene Cystic Fibrosis: A Defect in the CFTR Gene Alexandra L Allen Southern Union State Community College RAD212: Image Evaluation and Pathology Abstract What is Cystic Fibrosis? How does it affect people living with it? Cystic Fibrosis, also known as CF, is a life-threatening hereditary disease. It is inherited by a faulty cystic fibrosis transmembrane conductor (CFTR) geneRead MoreIntroduction. Cystic Fibrosis . Cystic Fibrosis (Cf) Is1323 Words   |  6 PagesIntroduction Cystic fibrosis Cystic fibrosis (CF) is a lethal autosomal recessive disorder with a clinical incidence of 1 in every 3500 newborns1. Currently, over 4000 Canadians have CF, with 60% being adults2. In the past, CF was considered a fatal disease with a life expectancy of less than two years, however, advances in enzymatic and antibiotic therapy have greatly improved the life expectancy of patients afflicted with CF3. Currently, the median age of Canadian CF patients is 50 years2. CFRead More Cystic Fibrosis Essay3952 Words   |  16 Pagessupplements, and other medications. In the past, the life expectancy of people with CF used to only be 8 years. However, with todays many medical advances, the average life expectancy is just under 30 years and is continuing to increase. Common cystic fibrosis symptoms involve: high amounts of salt (sodium and chloride) and potassium in sweat constant coughing and wheezing large amounts of mucus in the lungs recurring pneumonia failure to gain weight frequent, greasy

Capital Market Efficiency free essay sample

There are three types of market efficiency: O  Ã‚  Ã‚  Ã‚  Ã‚   when prices are determined in a way that equates the marginal rates of return (adjusted for risk) for all producers and savers, market is said to be allocationally efficient; O  Ã‚  Ã‚  Ã‚  Ã‚   when the cost of transfering funds is â€Å"reasonable†, market is said to be operationally efficient; O  Ã‚  Ã‚  Ã‚  Ã‚   when prices fully reflect all available information, market is said to be informationally efficient. Bachelier (1900): In the opening paragraph of his dissertation paper, he recognise that: â€Å"past, present and even discounted future events are reflected in market price, but often show no apparent relation to price changes†. Samuelson (1965): In his article, â€Å"Proof that properly anticipated prices fluctuate randomly†, he asserted that: â€Å"†¦competitive prices must display price changes†¦that perform a random walk with no predictable bias. † Therefore, price changes must be unforcastable if they are properly anticipated. Jensen (1978): says that prices reflect information up to the point where the marginal benefits of acting on the information (the expected profits to be made) do not exceed the marginal costs of collecting it. We will write a custom essay sample on Capital Market Efficiency or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Malkiel (1992): offered the following definition: â€Å"A capital market is said to be efficient if it fully and correctly reflects all relevant information in determining security prices. Formally, the market is said to be efficient with respect to some information set†¦if security price would be unaffected by revealing that information to all participants. Moreover, efficiency with respect to an informational set †¦implies that it is impossible to make economic profits by trading on the basis of (that informational set). † Lo and MacKinlay (1999): say: â€Å"†¦the Efficient Markets Hypothesis, by itself, is not a well-defined and empirically refutable hypothesis. To make it operational, one must specify additional structure, e. g. , investors’ preferences, information structure, business conditions, etc. But then a test of the Efficient Markets Hypothesis becomes a test of several auxiliary hypotheses as well, and a rejection of such a joint hypothesis tells us little about which aspect of the joint hypothesis is inconsistent with the data. † The â€Å"Bad Model† problem: Efficiency per se is not testable. It must be tested jointly with some model of equilibrium. When we find anomalus evidence on behavior of returns, the way it should be split between market inefficiency or a bad model of market equilibrium is ambiguous (Fama-1991) Tests of market efficiency: one must specify the information set used; * one must specify a model of normal returns (the classic assumpion is that normal returns are constant over time); * abnormal returns are computed as difference between the return on a security and its normal return, and forcast of the abnormal return are constructed using the chosen information set. If abnormal return is unforcastable, and in this sense â€Å"random†, then the hypothesis of market efficiency is not rejected. Tests of market efficiency – Weak-form tests The question is: How well do past returns predict future returns? The main assumption is that there should be no pattern in the time series of returns. Three theories of time series behaviour of prices can be found in the literature: * the fair-game model; * the martingale or submartingale model; * the random walk model. * Tests of market efficiency – Weak-form tests * The martingale model * Is also a fair game, where tomorrow’s price is expected to be the same as today (the expected return is zero).

Refinery Wastewater Management

Introduction As many countries around the world face high population and development growth, the water systems in place continue to face pressure as the demand for water continues to increase by the day. This high demand and use of water has led to an increase in effluent water discharges and raw sewage into the environment leading to environmental degradation and pollution.Advertising We will write a custom term paper sample on Refinery Wastewater Management specifically for you for only $16.05 $11/page Learn More Wastewater management activities have been developed to deal with the amount of effluent water in the environment and how this water can be recycled for reuse in domestic, industrial and agricultural functions (Shuping et al 2006). For water to be termed as wastewater, it has to undergo degradation in the form of contamination by organic waste materials, nitrate and phosphate pollution as well as bacterial contamination. Wastewater can however be treated for re-use by incorporating wastewater management activities that will reduce the amount of contamination to a level that is not harmful. Waste water management involves carrying out refinery activities on waste water so that it can be reused again for domestic, agricultural, and industrial purposes. Waste water management is carried out to reduce the amount of water that is disposed off in the environment as well as reduce the level of contamination in natural water sources. Many countries practice wastewater management so that they can limit the overdependence of natural water sources such as rivers, lakes and streams. Waste water reduces the amount of energy, time and costs that go in to treating water for reuse in water treatment plants. The most crucial aspect of waste water management processes is the collection and treatment of the effluent water. Wastewater Management The main aim of conducting treatment procedures on waste water is to remove any suspended solid materials that are in the effluent water before it can be discharged into the environment (Perlman 2010). When it comes to wastewater management activities, many industrial facilities rely heavily on the use of physical, chemical, physio-chemical and biological processes to treat wastewater and make it safe for disposal. Water processing plants that use chemical processes to manage the waste water have now turned to the use of zero-effluent techniques of waste management that ensure that the waste water can be re-used and the volume of waste water that is meant for disposal to the environment is minimized (Labrecque and Bedard 2004).Advertising Looking for term paper on environmental studies? Let's see if we can help you! Get your first paper with 15% OFF Learn More The satisfactory disposal of waste water will depend on the type of treatment that is used in treating the water before it is disposed off. Treating waste water before disposal is viewed to be an important activity as it prevents the contamination of the environment as well as preventing the contamination of other water resources such as rivers, lakes and streams. Waste water management involves the use of technology to improve the quality of the waste water before it can be disposed or re-used. The main aspects that underlie wastewater management involve the collection of the waste water to a central location such as a treatment tank where the water will be subjected to various treatment procedures. Because of the large volumes of wastewater, the treatment processes that are usually performed on the water have to be continuous to deal with the huge water volumes. Types of Wastewater Treatment Systems The features for most waste water treatment systems are usually determined by the nature of wastewater that is being treated and the amount of treatment that will be required to reduce the level contamination in the water. Wastewater can be treated by incorporating systems such as physic al, biological, primary, secondary, chemical and tertiary treatment systems. The minimum level of treatment required for waste water is the secondary treatment level but in cases where the level of contamination and pollution is high, the tertiary or advanced level of treatment is used (Viessman 2010) The various methods and techniques that can be used to treat wastewater are outlined below. Conventional Treatment System This wastewater approach incorporates the use of preliminary processes to remove heavy solid materials from the effluent water. The conventional treatment process eliminates the oxygen levels in the wastewater by metabolizing and flocculating the organic and non organic materials in the water. The preliminary processes will incorporate screening techniques which will screen out coarse and medium sedimentary materials in the wastewater.Advertising We will write a custom term paper sample on Refinery Wastewater Management specifically for you for only $ 16.05 $11/page Learn More The process will also measure the water flows and remove grit, solid waste from the water by shredding these solids to eliminate them from the wastewater. The sludge that results from the purification of the waste water is usually thickened and processed for disposal or use in land filling or for agricultural purposes (Viessman 2010). Primary and Secondary Treatment of Water The most common method that is used in the primary wastewater treatment system is that of sedimentation. This method removes 30 to 50 percent of solid materials in the wastewater by suspending them for elimination. To suspend these solids, the waste water is aerated and oxygen levels increased in the settling tanks to allow for floatation. The process of sedimentation in primary treatment systems must be done before any biological filtration process is performed. The organic material that remains from the primary treatment of waste water is usually extracted for use in th e secondary treatment process for biological materials (Viessman 2010). The use of the primary treatment system ensures that 60% of the suspended materials in the wastewater are removed (Perlman 2010). The main purpose of using primary treatment systems is to reduce the velocity of the wastewater so that suspended solids and floatable materials can settle in the surface of the water. The primary treatment devices that are used in treating the water include septic tanks, sedimentation tanks, flocculators, chemical feed units and upward flow clarifiers. The primary methods of treatment that are used in the secondary system are the use of activated sludge processes, biological contactors that are rotating and trickling filters. The activated sludge process involves feeding the wastewater into a tank that is aerated to allow for the breakdown of microorganisms in the effluent water which results in the formation of a microbial floc that settles below the tank. The sludge is then returne d to the aerated tank for secondary settling.Advertising Looking for term paper on environmental studies? Let's see if we can help you! Get your first paper with 15% OFF Learn More The aerated tanks have trickling filters and rotating biological contactors that are used to support the microbial flocs which have slime growths. The trickling filters and biological contactors are used in the treatment process to extract the organic materials or suspended solid materials from wastewater as it flows through the various stages of treatment. The sludge deposits or microbial flocs that settle below the tank are collected in a tank known as the secondary clarifier as the water flows out. The secondary treatment of wastewater removes 90 percent of suspended solids in the water (Viessman 2010). Tertiary Water Treatment Tertiary treatment systems are viewed to be the additional processes that are performed on the wastewater after it has gone through both the primary and secondary treatment systems. This method is employed when the two stages have failed to reduce the level of contamination in the water. For example, to reduce the amount of phosphorous in the water, the wa ste waters that are discharged to the receiving waters will have to undergo a eutrophic treatment procedure (Veissman 2010). Physical Treatment Processes For the treatment of waste water to be complete and effective physical treatment processes have to be performed on the water to ensure it is safe for disposal or re use. The physical process of waste water treatment will involve performing sedimentation, filtering, and aeration procedures on the water. In the sedimentation process, physical aspects that are related to the settling of suspended solids such as gravity are performed on the waste water. The sedimentation process involves holding the waste water for a short period of time in a storage tank that has been put under quiescent conditions. These conditions will allow for the heavy solids to settle and also eliminate the clarified effluent (Naik 2010) Sedimentation is one of the common physical procedures that are conducted at the beginning and end of the treatment process. T he aeration process involves adding oxygen to the wastewater so that the chemical compounds and bacteria in the water are reduced. Another physical process that can be used to treat waste water is by filtering where the water is passed through a filter that separates the suspended solids from the waste water (Naik 2010) Chemical Treatment Process The chemical treatment system involves the use of chemical processes such as chlorination, neutralization, coagulation and ozonation to reduce the amount of chemicals and bacteria in the water. Chlorination involves mixing the waste water with chlorine so as to kill bacteria and reduce the rate of decomposition in the water. Ozonation involves the use of a chemical known as ozone to disinfect the water form any bacteria that might be present as well as reduce the levels of contamination in the water. Neutralization is another chemical process technique that is used to treat waste water. This process involves adding acid such as lime to the water so that the pH levels can be adjusted to a neutral level (Naik 2010). Apart from neutralization, waste water can also be treated by performing the coagulation process which will entail adding chemicals such as polyvalent metals, ferric sulfate, ferric chloride, lime or aluminum sulfate to the waste water through a chemical reaction that will result in the formation of insoluble end products. These insoluble end products will be used to remove toxic substances such as hazardous chemicals or bacteria from the wastewater (Gautam et al 2007). Biological Treatment Processes This treatment process involves the use of biological micro organisms such as bacteria in the decomposition of the waste water to create stable end products. Micro organisms or sludges are formed in the waste water after which the waste is converted into carbon dioxide, or clean water. The biological treatment methods that can be used to treat wastewater are aerobic and anaerobic treatment methods. The aerobic p rocess involves the use of bacteria to consume the organic matter in the wastewater and convert it to carbon dioxide. Composting is also used in the aerobic process to treat the wastewater. The process of composting involves mixing the sludge with carbonated sources of material such as sawdust that will be used to treat the water (Naik 2010). The anaerobic treatment process involves fermenting the sludge at a particular temperature that excludes the presence of oxygen. The use of biological treatment in wastewater management activities is meant to remove any solids that might be organic or inorganic in nature. Biological processes are also performed on the water to reduce bad odor as well as destroy pathogenic organisms that might be harmful to the environment and that might impede biological activities (Gautam et al 2007). Preliminary Wastewater Treatment Systems This method of water treatment is used in most factory plants to protect the pumping of equipment and facilitate the tre atment of wastewater by removing or reducing the size of suspended solids or organic materials that are in the wastewater. Such solids include items such as plastic bottles, paper bags or other solid materials that float in water. The devices are also used to remove any heavy inorganic materials that are present in the waste water during the treatment process. The devices that are mostly used for this procedure include grit chambers, pre-aeration tanks, grinders, cutters and shredders as well as screen that will be used to separate the cut up materials from the waste water. Chlorination can also be used in the preliminary treatment to kill bacteria or organic bacteria that is in the water (Waste materials 2010). Sludge Treatment The solid waste that is removed after the primary and secondary treatment of the water is performed constitutes what is referred to as sludge. It is important to treat sludge before it is disposed off into the environmental as this material contains some haz ardous chemicals that might pose some risk to the environment. The treatment of sludge basically involves the removal of part or all of the water in the sludge to reduce the water volume. The treatment of sludge is also done to increase the decomposition of organic solids that are putrescible in nature to mineral or stable organic solids. The methods that can be used to accomplish this process include elutriation, wet oxidation, centrifuging or incineration (UNEP 2010). Screening Systems This is viewed to be one of the oldest systems of water treatment. Wastewater screening removes gross pollutants from the water so that the downstream equipment is protected from extensive damage and also prevent floating solids from entering the settling and septic tanks. The devices that are used in the screening process include wire meshes, rods, parallel bars and grating bars. The types of screen are divided into four categories which include the coarse screens, fine screens, very fine screens a nd microscreens. The coarse screens have openings that are more than 6 millimeters that are used to remove large solids such as bottles, rags, paper bags and debris. Such screens include catenary screens, reciprocating rake screens and cable driven coarse screens (ESCWA 2003). The fine screens have size openings of 1.5 to 6 millimeters that are used for reducing the amount of suspended solids during the primary treatment levels. Fine screens include rotary drum screens, rotary vertical disk screens, endless band screens and vibrating screens. The very fine screens have a size opening of 0.2 to 1.5 millimeters that are used to reduce the amount of suspended solids during the primary treatment level. The micro screens have small size openings that are 0.001 to 0.3 millimeters in size. These types of screens are used in the secondary and tertiary levels of wastewater treatment (ESCWA 2003). Flotation Wastewater Treatment This is an operation that is used to remove the solid or liquid p articles in the wastewater by incorporating the use of fine gas and air bubbles. The gas bubbles are trapped in the particle structure of the suspended solids that will make the solid buoyant. Particles that have a higher density than the liquid will rise with the buoyancy. Once the particles have floated to the surface they are eliminated out of the water by filtering or screening. The primary device that is used in the flotation process is oxygen or air. Other devices that can be used in the process include chemical additives that can be used in enhancing the skimming process. The flotation methods that can be used on suspended solids include air flotation where gas in introduced into the liquid stage, dissolved air flotation where air is injected while the wastewater is subjected to high atmospheric pressure, vacuum flotation where the wastewater is saturated by using air in an aeration tank or in a waste water pump. A partial vacuum is then applied to dissolve the air. The chemi cal additives method of flotation involves the use of chemicals in creating a surface that will easily adsorb the air bubbles in the settling tank. Chemicals such as ferric salts and aluminum are used in this technique of flotation (Metcalf and Eddy et al 2003). Natural Treatment Systems These wastewater treatment techniques are designed to incorporate the use of physical, biological and chemical processes that occur in natural ecosystems such as the interactions that take place in plants and vegetation, soil composition and nutrients, water and micro organisms. Natural treatment systems include the treatment of land, floating acquatic plants, and constructed wetlands. These treatment processes are usually performed after mechanical pretreatment techniques have been done on the wastewater. Land treatment involves the controlled application of the wastewater at a rate that can be compared to the natural chemical, biological and physical process that takes place naturally on the land. The types of land treatment systems that are used are slow rate systems, overflow and rapid infiltration systems (Metcalf and Eddy et al 2003). The slow rate system involves applying the wastewater to vegetated lands through the incorporation of techniques such as sprinklers and irrigation methods. The wastewater is applied within a duration of 4 to 10 days so that the aerobic conditions in the water can be maintained. The rapid infiltration technique involves using intensive methods to apply the water such as hydraulic and organic loadings at an intermittently and shallow infiltration rate. The overflow treatment process involves treating the wastewater as it flows down a network of vegetated terraces that are sloppy. The water is applied in an intermittent pattern to the upper parts of each terrace. This allows the water to flow down to the other terraces through runoff collection channels. The devices that are used in the overflow technique include high pressure sprinklers, gate d pipes, and low pressure sprays (ESCWA 2003). Conclusion The treatment of waste water has become a critical activity due to the diminishing water resources in the world that have arisen due to high population growth and developments in the urban worlds. The treatment of wastewater is therefore seen to be an important activity in minimizing the over reliance on natural water resources as well as reduce the amount of water that is disposed off into the environment. Wastewater treatment activities are also viewed to be important in reducing the amount of hazardous chemicals and solid wastes that are found in the water as they eliminate these materials during the treatment process. The various techniques that have been outlined are all effective methods of carrying out wastewater management activities. References Economic and Social Commission for Western Asia (ESCWA) (2003) Wastewater  treatment technologies: a general review. Web. Gautam, A, K., Kumar, S., and Sabumon, P.C., (2007) Preliminary study of physico- chemical treatment options for hospital wastewater. Journal of Environmental  Management, Vol.83, No.3, pp.298-306. Labrecque, R. and Bedard, N. (2004) Combining membranes with mechanical vapor Recompression. Chemical Engineering Journal, Vol.111, No.2, pp.51-54. Metcalf and Eddy Inc., Tchobanoqlous, G., Burton, F., and Stensel, D.H. (2003)  Wastewater engineering: treatment and reuse. 4th Edition. New York: McGraw Hill. Naik, A. (2010) Wastewater treatment methods. Web. Perlman, H. (2010) Water use: wastewater treatment. Web. Shuping, L., Siuqing, L., Chocat, B., and Barraud, S., (2006) Requirements for sustainable management of urban water systems. Environmental Informatics, Vol.6, pp.116-128, UNEP (2010) Sludge treatment, reuse and disposal. Web. Viessman, W. (2010) Wastewater treatment and management. Web. Waste Material (2010) Wastewater treatment methods. Web. 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