The purpose of this experiment Essay Example for Free

The purpose of this experiment Essay The purpose of this experiment is to measure the pulse flow of blood through the finger and correlate it with ECG. In addition, we examined the effects of hot and cold temperature on peripheral circulation. It was hypothesized that the temperature and exercise would increase the cardiac cycle and pulse pressure. Three participants were doing the experiment. A 19 year old female, who weighs 110 pound, drinks coffee often times and nonsmoker, did the exercise. A 20 year old female, weighs 135 pounds, non coffee drinker and nonsmoker did the cold temperature. Also a 20 year old female, weighing 106 pounds, non smoker and non coffee drinker did the hot temperature. Electrodes were placed on left ankle, right hand and left hand. Besides that, pulse transducer was attached in finger. Baseline was established, 3 cardiac cycles and 3 pulse pressures were measured at rest. We did this in the same way for each individual. In addition, we did 3 cardiac cycles and 3 pulse pressure after exercise and temperature experiment. The effect of cold temperature did make variation in heart rate and pulse. Figure 1 shows that heart rate decreased when participant placed her hand in cold water. In the same way, figure 2 shows decrease in heart rate when the participant placed her hand in hot water. Figure 3 shows that exercise increased the heart rate of the participant. The results we observed for the cold temperature experiment was decrease in temperature. In other words, we observed a gradual decrease in heart rate after the participant put her hands in cold water. In addition, we noticed an increase in pulse rate after the experiment. Also, we noticed decrease in heart rate and increase in pulse rate for hot temperature experiment. But when I did research I found that the heart rate should increase in cold temperature and should decrease in pulse rate. Also for the hot temperature the heart rate must increase and pulse rate should decrease. So I can not interpret the result. However, for the exercise we noticed increase in heart rate and pulse rate. Resting and exercise heart rate are controlled by the sympathetic and parasympathetic nervous system. The sympathetic division of the autonomic nervous system prepares the body for physical activity by increasing heart rate, blood pressure and respiration. Once exercise begins, the sympathetic nervous system is activated and the heart rate rises quickly. The parasympathetic division helps slow down heart rate and respiration. At rest, the heart is controlled by the parasympathetic division, which is why the average resting heart rate is 72 bpm or less. During exercise, the release of epinephrine and norepinephrine stimulate receptors in the heart which causes heart rate to increase. J. Grayson, Reactions of the peripheral circulation to external heat, J Physiology vloume 1, pg 53-63. www. pubmed. com Sandercock, et al. Effect of exercise on heart rate variability, 03/28/2005, www. medscape. com M Buchheit, J J Peiffer, C R Abbiss, P B Laursen. Effect of cold water immersion on postexercise parasympathetic reactivation. American Journal of Physiology : Heart and circulatory physiology 296. 2 (2009): H421. Sciences Module. ProQuest. University Park, PA. 23 Feb. 2009 http://www. proquest. com

Cameroon Volcanic Line (CVL) Origin and Features

Cameroon Volcanic Line (CVL) Origin and Features Leandri Venteru Mid- African Rift: Is there a geographical/spatial control on the nature of volcanism in Cameroon? Essay Volcanism in Cameroon occurs mainly on the Cameroon Volcanic Line (CVL), with the largest and most active volcano being Mount Cameroon (Fitton, 1980). The CVL, representing alkaline volcanoes, shows an easy recognisable Y-shape, with volcanic centres in both the oceanic and continental sectors of the African plate (Fitton Dunlop, 1985). Consensus regarding the driving forces of these volcanoes has yet to be reached. However, a wide variety of theories and hypotheses addressing the origin and nature of the CVL have been published over the last few decades. The CVL is a 1600km long magmatic sequence, stretching from Pagalu Island in the Gulf of Guinea (Atlantic Ocean) to Lank Chad on the main land of Cameroon on the western African continent (Dà ©ruelle, Ngounouno Demaiffe, 2007). Geographically the CVL is situated almost parallel to the Benue Trough, and follows the length of the Ngaoundà ©rà © Fault (Ballentine, Lee Halliday, 1997). The northern limb of the CVL overlaps with the Chad rift, which marks the northern rift of the Benue Trough (Fitton, 1980). Although volcanism is still active along the CVL is it not a neogene feature and has been active since the beginning of the Tertiary period. The rocks from the CVL are classified as mainly alkaline, intermediate and felsic. The felsic and basaltic lavas increase inlands towards the branches of the CVL in a volumetric ratio (Dà ©ruelle, Ngounouno Demaiffe, 2007). One of Africa’s largest volcanoes, Mount Cameroon, is a volcanic horst, with an approximate height of 4075m. T he volcano of Mount Cameroon is the most active volcano on the CVL. The latest eruption of Mount Cameroon was in the year 2000 (Herrero-Bervera et al. 2004). Scientists tried various methods over the years in an attempt to clarify the origin and dynamics of the CVL. During the 1980’s Fitton (1980) proposed a simple model to explain the geological features of the CVL. Fitton (1980) noted that although there is no evidence for rift faulting there are signs of regional uplift of the basin. The continental sector of the CVL is characterized by strato-volcanoes (Mount Cameroon), central volcanic massifs and even calderas in some areas. Collapsed plains filled by sediments, single magnetic volcanoes and flood basalts ( Ngaoundà ©rà © Plateau) are also prominent on the continental sector (Nkouathio et al. 2008). The volcanism is not influenced by fractures, which existed before the volcanism in the basement (Fitton, 1980). The origin of the CVL is explained by hand of the striking relationship between the CVL and the Benue Trough features. Fitton (1980) suggested that the CVL and the Benue Trough are superimposed by rotating one feature by 7 ° in relation to the other, about an axis. The axis is described to run with a north eastern strike into the country of Sudan. The reason for the relative rotation of the CVL and the Benue Trough is speculated to be as a result of the clockwise rotation of Africa (ca. 80Ma – 65Ma) (Fitton, 1980). This clockwise rotation might provide evidence for three features. Firstly, on the origin, the size and Y-shaped geometry of the CVL, secondly the rotation might support reason for the absence of recent volcanism in the Benue Trough. Thirdly, the rotational theory might provide evidence for the folding of the Benue Trough sediments. There were some speculations that the volcanism presently active in the CVL was once active in the Benue Trough. If the volcanic line had migrated from the Benue Though to its current position a systematic migration of a hot-spot is implied. Ngako et al. (2006) used remote sensing data as proposed by Moreau et al. (1987) to suggest that the relati onship between stress regimes and intraplate alkaline magmatism in the CVL is controlled by lithospheric structures. Ubangoh et al. (2005) argued that the presence of numerous recent volcanic cones and craters along the CVL is an indication of a strong geothermal gradient beneath the volcanic line, although there are no data that proves an increased supply of heat. By using a geochemical study on the basaltic rocks of the CVL and a K-Ar dating programme, Fitton and Dunlop (1985) searched for evidence to prove a systematic migration of the CVL volcanoes. Since the CVL is situated in such a unique geological setting, Fitton and Dunlop (1985) reasoned that they can determine the source of the CVL magmas by comparing the isotopic ratios of alkali basalts on the oceanic sector with the isotopic data of the alkali basalts on the continental sector of the volcanic line. Fitton and Dunlop have found that both the major element compositions as well as the isotopic ratios are indistinguishable when comparing the oceanic and continental sectors. What the K-Ar data did prove was that multiple volcanoes were ac tive along the line in more or less the same time period. When Ballentine, Lee and Halliday (1997) compared the ages of the oceanic sector volcanoes, they found that there is a consistency between the rotation of the Cretaceous African plate (Fitton, 1980) and the ages of the earlier exposed rocks on the islands. The ages of the early exposed lavas decrease from the continental side towards the ocean, placing Principe at 31Ma and Pagalu at 4.8Ma. The systematic age decrease of the islands support the mantle plume model for the oceanic sector of the CVL, but does not include the continental sector. Other causes of volcanism, such as rift faulting and pre-existing basement fractures were at first discarded due to failure to collect supportive evidence. The volcanoes on the ocean floor showed no changes due to the faults they passes through, thus one can assume that the source of these volcanoes are from mantle processes and is not affected by structures occurring in the crust (Fitton, 1980).Research based on the age and chemistry of the CVL basalts, indicated that the CVL is a young rift associated with the Benue Trough rather than a hot-spot trail. The depth at which a volcano is tapping its magma can be determined by the radioactive decay of helium isotopes in crustal rock (Aka, et al. 2003). Helium serves as a geochemical tracer that could be used to investigate the alteration of magma over a period of time. It is generally accepted that ocean island basalts (OIB) show a wide range of 3He/4He (Zindler Hart, 1986) and that 3He/4He ratios from mid ocean ridge basalts (MORB) are uniform (Graham et al. 1992a). The 3He/4He ratio of the CVL ranges from 3.05Ra to 8.31Ra. Hotspots in general have much higher 3He/4He ratios (Hilton et al. 1999). Aka et al. (2003) was the first to identify that the distribution of the 3He/4He ratios on the CVL could be due to spatial control, and suggested that the helium isotopic distribution an essential characteristic of the CVL is. These findings are argued as prove that the CVL volcanoes doesn’t tap their material directly from hotspots. Aka et al. (2003) is further backed up by work Fitto n and Dunlop (1985) did on K-Ar dating and the consistency to the Pb-isotope model proposed by Halliday et al. (1990).The above mentioned data and the long-lasting volcanism of the CVL volcanoes supports the conclusion reached by Fitton and Dunlop (1985) that the magma driving the volcanoes on the continental sector could not originate from a deep mantle source. Therefore the CVL shows no evidence of a mantle plume in the continental sector, but rather signatures convection of the upper mantle (Fitton Dunlop, 1985). 206Pb/204Pb and 208Pb/204Pb isotope ratios showed a slight decrease to either sides of the volcanic line from the centred volcano, Mt. Cameroon, which lies on the lithospheric continental-oceanic boundary (COB) (Ballentine, Lee Halliday, 1997). Basalts from the COB volcanoes, such as Mount Cameroon and Mount Etinde are more radiogenic with 206Pb/204Pb ratios of approximately 20.52 and 208Pb/204Pb ratios of 40.34 (Dà ©ruelle, Ngounouno Demaiffe, 2007). The Pb ratios of the COB volcanoes show a strong contrast to the lower radiogenic ratios of the island volcanoes. Basalts from the island located far south from the COB, Pagalu Island, have the lowest 206Pb/204Pb ratio of 19.01 and a 208Pb/204Pb ratio of 38.83. The Pb isotope data proves that there occurred no consistent major change in the magma over a period of time. The Nd and Sr isotopes of the basalts from both the continental and oceanic regions are similar in composition. The resemblance of the geochemical and isotopic data be tween oceanic and continental basalts provide evidence that the source and composition of the magma was not influenced by the continental crust, and therefore, the magma does not originate from the lithosphere (Dà ©ruelle, Ngounouno Demaiffe, 2007). The magma, as speculated by Ballentine, Lee and Halliday (1997), originate from a sub-lithospheric source, because of the similar compositions of the oceanic and continental magmas. Nkouathio et al. (2008) argued that since the lavas of the entire CVL have a shallow asthensopheric mantle source a depleted MORB mantle and a metasomatosed mantle, the alkaline lavas are consistent with the asthensopheric upwelling of a hot-spot. Halliday et al. (1990) argued that the isotopic decreases could infer re-melting of an enriched mantle plume located beneath the COB. Halliday further argues that the plume possibly shifted (from its position underneath the Benue Trough) to its current location during the continental breakup between the African an d South American plates as well as the rotation of the cooler lithosphere relative to the asthenosphere (Ballentine, Lee Halliday, 1997). Ballentine, Lee and Halliday (1997) made it clear that although the isotopic data supports the mantle plume theory, the mantle plume is only a part of the explanation of a more complex volcanic setting. Detailed isotopic data demonstrated that many theories proposed in the past were too inconsistent to explain the origin of the CVL. The data includes many classical theories, however only three will be mentioned. Firstly, the reactivation of the Ngaoundere fault which in turn caused the volcanism on the CVL (Moreau et al. 1987). A second classical theory involves membrane tectonics which produced the extensional CVL feature (Freeth, 1979). Thirdly, it is suggested that the various active volcanic centres are inconsistent with the ‘textbook’ model of hotspots (Fitton Dunlop, 1985), (Ballentine, Lee Halliday, 1997).Keeping the above mentioned theories in mind, Ballentine, Lee and Halliday (1997) used a ‘technique of inductively coupled plasma magnetic sector multiple collector mass spectrometry’ (Ballentine, Lee Halliday, 1997 pp 111)to acquire new data. From the data Ballentine, Lee and Halliday (1997) concluded that the CVL does not show a mentionable dif ference in Hf and Nd isotopic compositions in neither the continental margin nor in the oceanic sectors. However, a very significant difference in Pb and Sr isotopic compositions were detected (Ballentine, Lee Halliday, 1997). The consistent Hf and Nd isotopic compositions in the ocean island basalts (OIB) are indicative of a similar behaviour of the Sm/Nd and Lu/Hf parent-daughter ratios in the source of the OIB (Ballentine, Lee Halliday, 1997). Further, the continental sector shows a similar Hf-isotopic make-up than the oceanic sector. Ballentine, Lee and Halliday (1997), argued that the distinct variability in the Pb isotopic composition can be explained by the recycling of the oceanic crust, since Pb and Sr have increased mobility in the oceanic lithosphere. Kamgang et al. (2008) used a more localized approach, by investigating the geochemical isotopic data of the Bamenda Mountains in Cameroon. Since the previous isotopic studies performed by Ballentine, Lee and Halliday (1997), focussed on the entire CVL, Kamgang et al. (2008) proposed a ‘zoomed in’ investigation by focussing on one area of the CVL and try to explain the origin of the magma in that area. Kamgang et al. (2008) performed geochemical and geochronological studies of the mafic rocks from the Bamenda Mountains. His aim was to gain a better perspective of the composition of the CVL magma source. K-Ar dating performed on older, crust contaminated, samples of the CVL showed no systematic variation over time. However, insight on the chemical composition of the mantle source of magma is provided by the high Eu, Sr and Ba concentrations (Kamgang et al. 2008). The high concentrations are not a result of crustal contamination, because these concentrations do not correlat e to the Sr and Nd isotopic compostitions or the MgO contents or the La/Nb ratios of the rocks. Kamgang et al. (2008) suggested that these high concentrations rather have to do with the composition of the magma origin. The major element composition shows consistency with fractional crystallization processes. Sr and Nd isotopic values of the Bamenda Mountains coincide with the isotopic data published by Ballentine, Lee and Halliday in 1997. Kamgang et al. (2008) pointed out that the positive correlations observed between the Pb and Nd isotopic ratios and the negative Pb/ Sr isotopic correlation indicate either contamination by the continental crust (Ngounouno, Dà ©ruelle Demaiffe, 2000) or the effect of an enriched lithospheric mantle (Rankenburg, Lassiter Brey, 2005)( Kamgang et al,2008). Structural causes of volcanism have been discarded due to failure to prove structural influences with supportive evidence. There are three main structural units present in the Pan- African basement, namely shear zones, fold zones and thrust zones from which the shear zones indicating lithospheric faults stands out (Ngako et al. 2006).The volcanoes on the ocean floor show no changes due to the faults they passes through, thus one can assume that the source of these volcanoes are from mantle processes and is not affected by structures occurring in the crust (Fitton, 1980). It was also speculated that the CVL is rather a young rift associated with the Benue Trough. Nkouathio et al. (2008) suggested that the CVL is an alternating structure consisting of horsts and grabens. As a large shear zone, the CVL is structurally subdivided by a sequence of faults indicative of an alternating horst and graben system (Nkouathio et al. 2008). Considering other tectonic models, Ngako et al. (2006) suggested that the magmatism of the CVL is a complex interaction of multiple mantle plumes and fractures in the lithosphere. Ngako et al. (2006) further speculate that the complex interaction may cause the new magmatic complexes to be diagonally aligned. By expanding the study area form only the CVL to other large scale magmatic provinces on the African continental plate, Ngako et al. (2006) tries to illustrate a complex interaction between hotspots and Precambrian faults. The aim is to provide alternative explanations to classical hotspot models. Ngako et al. (2006) used three provinces, namely the Niger- Nigeria super province (Plaeozoic to Mesozoic era), the Benue Trough (Cretaceous period) and the Cameroon Volcanic Line (Cenozoic era to present) to prove a time-space migration of the West-Central African alkaline magmatism. The ages of rocks sampled, decrease from the northern Niger- Nigeria province southwards through the Be nue Trough to the CVL. The decreasing age of the plutonic provinces may suggest an interaction between tectonics and a hotspot system. Ngako et al. (2006) noted that the crustal and elastic thickness of the lithosphere on the continental sector of the CVL is unusually thin. This lithospheric thinning is argued as a position of a hotspot. Nkouathio et al. (2008) suggested that the evolution of the CVL magmas could be explained by the pattern of tectonic stresses and volcanic structures. In contradiction, Milelli, Fourel and Jaupart (2012) suggested that the Y-shape of the CVL was unaffected by plate motions and therefore implies that the magma source is attached to the continent. Geophysical surveys performed on the crust of the CVL concluded that differentiation between the Pan-African belts and neither the structural features nor the thickness of the crust is possible (Milelli, Fourel Jaupart, 2012). The crust underneath the CVL is very thin (ca. 35-39km) and the failure to distinguish between the Pan-African belts and the CVL indicates that the long period of magmatism (for approximately 70 Myr) on the CVL, has not have significant effects on the crust in the CVL region (Tokam et al. 2010). The absence of a seismic velocity anomaly at depths greater than ~300km, confirm the presence of the uniform mantle transition zone (Reusch et al. 2010)(Milelli, Fourel Jaupart, 2012). Milelli, Fourel and Jaupart (2012) explored the buoyancy of the lithospheric origin, because the lithosphere is made up of depleted mantle material, relative to the asthenosphere as a basis for their experiment on lithospheric instabilities. Since the lithosphere is buoyant on the asthe nosphere, the system is in equilibrium. However, if the lithosphere would experience cooling from the top, a convective instability might be triggered (Milelli, Fourel Jaupart, 2012). The latest trend is that researchers consider the CVL as a hot line tapping its resources from a sub-lithospheric mantle through openings in the lithosphere (Dà ©ruelle, Ngounouno Demaiffe, 2007). Crustal uplift in both continental and oceanic areas proposed by Meyers et al. (1998) contributes to the theory of lithospheric instability proved by Milelli, Fourel and Jaupart (2012) via laboratory experiments. Milelli, Fourel and Jaupart (2012) studied the lithospheric instability due to cooling from the crust downwards. The lithospheric instability is speculated to occur within the sub-continental lithospheric mantle. The laboratory experiments performed by Milelli, Fourel and Jaupart (2012) were based on the principle that materials with a viscosity that is independent of temperature will react the same when cooling from either the top or the bottom was induced. A ‘continents’ were created by using different viscosity fluids and fixing certain variables. These experiment s, that’s been fully described and discussed by Milelli, focussed on the instabilities created at the continental margin. Milelli, Fourel and Jaupart (2012) documented that the buoyancy factor causes downwellings that eventually return to the surface. This cycle of downwellings and upwellings creates a stress regime where compressional stresses were identified at the downwellings and corresponding extentional stresses, creating rifting fractures, at the upwellings. Fracture patterns on the surface of the experimental ‘continent’ formed in a combination of hexagons and distorted squares (Milelli, Fourel Jaupart, 2012). The conclusion of these experiments serve as proof that that continental lithospheric cooling can result in the geometrical Y-shape of the CVL, independent of the size and shape of the continental mass. Further proof is presented by Dà ©ruelle, Ngounouno and Demaiffe (2007) with supporting data on seismic and gravimetric surveys of the oceanic sec tion of the CVL.

Environmental Toxicology and Human Health

Environmental Toxicology and Human Health Environmental Toxicology and Human Health Environmental Toxicology is a field of science with various disciplines involved in the study of the adverse effects of various physical, chemical and biological agents on living organisms particularly animals, birds and fishes (Philp, 2001, pp. 10-11). Physical agents. They are sources of energy that may have negative effects on human health and that of biological organisms such as fish, birds and animals (Philp, 2001, pp. 20-25). One such agent is noise which can be defined as unwanted sound. Noise has both permanent and temporary damage to the ears rendering one incapable of hearing or resulting to tinnitus both of which are irreparable (McCally, 2002, pp. 58-67). Noise in the workplace also poses a threat to the workers in that they may fail to hear sounds indicating threats. Vibration, also a physical agent is categorized into two: hand-arm vibration (HAV) and whole body vibration (WBV). Continuous exposure to HAV has been proven to lead to hand-arm vibration syndrome a permanent and incapacitating health effect such as musculoskeletal disorders of the hand (McCally, 2002). On the other hand, continued exposure to WBV is associated with severe pain on the lower posterior. Optical radiation also has some grim effects on the health of people. Ult raviolet radiation emanated by the sun presents the utmost danger to our health. When exposed to the eyes it may lead to spoiled cornea and severe pain while exposure on the skin may vary from burning, redness and hastened ageing through skin cancer of different types. Electromagnetic fields (EMFs) generated due to electrical energy used may also be detrimental (Philp, 2001). Though they seldom occur, constant exposure to the EMFs can result to severe effects depending on the frequency of the radiation. Electricity can also be viewed as a threat since it may lead to death or severe injuries such as electric burns, thermal burns and electric burns to people. Last but not least we have ionizing radiation. Contact with low-level ionizing radiations may lead to cancer and DNA mutations while high-level exposures cause radiation sicknesses and burns (Philp, 2001). Biological agents. These include bacteria, viruses, fungi, other microorganisms and toxins associated with them. While some of these agents have no harmful implication on the human health, others have the potential to affect the human health in various ways ranging from moderately mild, allergic reactions to serious medical illnesses even demise. These agents occur widely in the environment (Environmental Toxicology And Human Health, n.d.). Biological agents have the capacity to reproduce rapidly, require little resources to live and can poison at very small doses thus they are a probable danger in a widely in our environment. Biological agents can be categorized into four sets according to their severity of infection and likelihood of prevention and treatment (McCally, 2002, pp. 150-200). Group 1 agents are those with low chances of causing ill effects to the organisms. Group two consists those toxicities that are unsafe for the workers but chances of spreading to the community are very minimal. Group 3 agents are those that can cause severe human disease, pose a serious threat to the workers and are likely to spread to the community. However, these toxicities can be treated. Group 4 agents are similar to group 3 agents except for the fact that there is no effective management for them. These are some of the most contagious and extensive biological agents: anthrax, botulism, avian flu, and Ebola (Environmental Toxicology And Human Health, n.d.). Chemical agents. These are as a result of the products we use in our day to day doings. Pesticides are a perfect instance of chemical toxins (Lakind). Pesticides persist in the environment long after their use which can result in bioaccumulation of chemicals in various organisms along with biomagnification within a group of organisms that depend on each other for food. Dichlorodiphenyltrichloroethane (DDT) is another agent that was banned due to its negative effects on living organisms (Lakind). The reactions chemical toxicities is dependent on several factors that I will briefly discuss. Age is a significant aspect in establishing the response to a toxic chemical (Lakind). For example, parathion is more lethal to young animals. Although very rare, sex can determine the response to a toxicant. For instance, when exposed to parathion the female rat is twice as affected as the male rat. The responses to a toxic chemical also depends on the species (Safe). For example, insecticides are lethal to insects but relatively non-toxic to animals. Toxicity of a chemical is determined by factors such as: the dosage-it is the most critical factor if a substance will be acute or a chronic toxicant (Lakind). The form that a chemical agent is in also defines its toxicity. For instance, the poisonousness of mercury in gas form is very different from methyl mercury. The entry point of a toxin is also a measure of its toxicity. One other factor is the rate of removal from an organism’s system. According to Paracelsus all substances are poisons only the dose differentiates whether it is a poison or a remedy (Safe). Exposure assessment is the process of establishing the regularity, period and expansiveness of exposure to toxicities together with the traits and number of the population exposed. Methods of exposure assessment include direct and indirect approach (Philp, 2001, pp. 100-108). In direct approach exposure to the agents is determined by monitoring the pollutant concentrations reaching the person while in indirect approach the toxicant concentration is measured during specific human activities to predict the exposure distributions within a population (McCally, 2002). Epidemiology is important to research studies of environmental health since many environmental exposures can be addressed only by comparing populations instead of individuals and the interruption of both local and universal environments require us to come up with new methods of study design that is epidemiology. The epidemiologic approach to studying environmental health problems has its limitations. One of such constraint i s the quick changes in the health and nutritional status of many populations that have been affected majorly which may lead to inconclusive results (Safe). Another limitation is the fact that data collected through epidemiology is often ignored and limited by factors such as limited resources, personal priorities, political concerns and public relations (Philp, 2001). Since epidemiology depends on valid data, restriction on the gathering of data can be considered a constraint. This may be due to insecurity or lack of resources preventing the researchers from submitting surveillance data (Safe). References. Environmental Toxicology And Human Health. (n.d.). Retrieved from http://docsfiles.com/pdf_environmental_toxicology_and_human_health.html Lakind, J. S. (n.d.). Workshop on Human Milk Surveillance and Research on Environmental Chemicals in the United States. journal of Toxicology and Environmental Health, Part A. McCally, M. (2002). Life support the environment and human health. MIT Press. Philp, R. B. (2001). Ecosystems and human health: toxicology and environmental hazards. Lewis Publishers. Safe, S. (n.d.). Toxicology, Structure-Function Relationship, and Human and Environmental Health Impacts of Polychlorinated Biphenyls: Progress and Problems. Environmental Health Perspectives.

Essay --

Stalin’s Rise What effective tactics did Joseph Stalin use to rise to power? Emily Goetz 3-10-2014 Word Count 4th hour Question: What effective tactics did Joseph Stalin use to rise to power? Thesis: Over the course of several years, Stalin consolidated his power through the use of political scheming, maintaining a respectable image, and by out-maneuvering his opposition in the Communist Party. A. Plan of Investigation: Over the course of several years, Stalin established his power through the use of political scheming, maintaining a respectable image, and by out-maneuvering his opposition in the Communist Party. Stalin’s rise shows the importance of how political figures maneuver their way to the top and how a dictator achieves legitimacy. In the future, when leaders are rising, they can be compared to Stalin’s and stopped if there are close similarities in ruthlessness. This paper is narrowed to Stalin’s rise to better elaborate on several of the tactics Stalin used to obtain power. I need to find videos from history to show what Stalin was like physically around others. I need to locate speeches, and perhaps recording by other party members about Stalin to show Stalin’s ruthlessness. B. Summary of Evidence: Stalin was drawn into the city’s revolutionary circles after â€Å"discovering the works of Karl Marx† (McKinney). In 1903, the Russian Social Democratic Labor Party split into two, known as the Bolsheviks and the Mensheviks. Stalin joined the Bolsheviks, led by Vladimir Lenin. Between â€Å"1902 and 1913 Stalin was arrested and sent into Siberia seven times† (Haugen). Between exiles Stalin continued work for the Bolsheviks and met Lenin for the first tim... ...de sure to give only those who agreed with him any power, and eventually Congress was filled with a majority of Stalin supporters. When Stalin’s opponents took the left side, Stalin took the right and vice versa. As a result, Stalin maneuvered his way into the Party so much that he practically guaranteed his own success as Lenin’s successor. By the time the Party's core realized what had happened, it was too late, and the only person with the authority to challenge him, was on his deathbed and incapable of speech after a series of strokes. Stalin took down Leon Trotsky and in 1925, and forced Trotsky to resign from the party. Stalin exiled Trotsky from the Soviet Union in 1929, and had him assassinated in Mexico in 1940 (Stalin). Stalin knew how to use his position as an advantage, even to the point of abusing his powers, so they he could defeat his opponents.

A Feminist Perspective of Othello Essay -- Othello essays

A Feminist Perspective of Othello  Ã‚  Ã‚      Shakespeare’s tragic drama Othello closes the final scene of the last act with the spiritual superiority of the heroine firmly established over that of the hero. This is one of many aspects regarding the feminine perspective on the drama, the subject of this essay. A.C. Bradley, in his book of literary criticism, Shakespearean Tragedy, describes the violence against the heroine as a â€Å"sin against the canons of art†: To some readers, again, parts of Othello appear shocking or even horrible. They think – if I may formulate their objection – that in these parts Shakespeare has sinned against the canons of art, by representing on the stage a violence or brutality the effect of which is unnecessarily painful and rather sensational than tragic. The passages which thus give offence are probably those already referred to – that where Othello strikes Desdemona (IV.i.251), that where he affects to treat her as an inmate of a house of ill-fame (IV.ii), and finally the scene of her death. (174) At the outset of the play only the male perspective is given: Iago persuades the rejected suitor of Desdemona, Roderigo, to accompany him to the home of Brabantio, Desdemona’s father, in the middle of the night. Once there the two awaken the senator with loud shouts about his daughter’s elopement with Othello. In response to the noise and Iago’s vulgar descriptions of Desdemona’s involvement with the general, Brabantio arises from bed. With Roderigo’s help, he gathers a search party to go and find Desdemona and bring her home. The father’s attitude is that life without his Desdemona will be much worse than before: It is too true an evil: gone she is;   Ã‚  Ã‚  Ã‚   And what's to come of my despised... ...espearean Tragedy. New York: Penguin, 1991. Di Yanni, Robert. â€Å"Character Revealed Through Dialogue.† Readings on The Tragedies. Ed. Clarice Swisher. San Diego: Greenhaven Press, 1996. Reprint from Literature. N. p.: Random House, 1986. Gardner, Helen. â€Å"Othello: A Tragedy of Beauty and Fortune.† Readings on The Tragedies. Ed. Clarice Swisher. San Diego: Greenhaven Press, 1996. Reprint from â€Å"The Noble Moor.† British Academy Lectures, no. 9, 1955. Heilman, Robert B. â€Å"Wit and Witchcraft: an Approach to Othello.† Shakespeare: Modern Essays in Criticism. Ed. Leonard F. Dean. Rev. Ed. Rpt. from The Sewanee Review, LXIV, 1 (Winter 1956), 1-4, 8-10; and Arizona Quarterly (Spring 1956), pp.5-16. Shakespeare, William. Othello. In The Electric Shakespeare. Princeton University. 1996. http://www.eiu.edu/~multilit/studyabroad/othello/othello_all.html No line nos.

Bilingual Education Beneficial for Kinderkarten

Bilingual Education: Beneficial for Kindergarten to Catch it Young By M. H 7th December 2012 Abstract: Research has shown that bilingual education has positive effect on kindergarten children. The purpose of this research was to study the benefits of bilingual education, which further helped in recommending marketing campaign for the Canadian kindergarten school to increase enrolments. Several analyses were taken into account like â€Å"Simon Task† and core group task to understand the benefits. Study reveals that bilingual children perform better cognitive, analytical tasks and have better success rate than monolingual children.Keywords: Children, Bilingualism, Kindergarten, Cognitive, Bilingual, Education, Monolingual Page | 1 Introduction This report aims to address positive effects of bilingual education on young children and to provide recommendations to Canadian kindergarten school through marketing campaign to increase kindergarten student enrolment. Different research methodology taken into account in this report, which has been extracted from researches done by PhD students, professors, doctors and scientists to provide evidence on the benefits of learning in two languages.One of the approaches considered in this report was â€Å"Simon Task† conducted by Ioulia Kovelman and Ellen Bialystok, PhD student of York University, Canada. This provides empirical evidence that bilingual kids outperform cognitive tasks than monolingual flock. Moreover, Bilingual children are more creative, intellectual and have longer attention span. Findings 1. 1 Perform Cognitive Tasks Better Several researches were undertaken in the past 20 years; to prove bilingual children are superior to monolingual kids.In the recent past, Ioulia Kovelman and Ellen Bialystok, PhD student of York University, Canada evaluated children aged between 4-6 years. During their research, they made two core groups, one group was monolingual who were fluent in their native language . i. e. French or English and another; group was bilingual (with proficiency in both the languages, written and oral). The idea was to test cognitive ability of the core group for which â€Å"Simon Task† method was considered. It is a universal method practised by scientists to understand how human mind functions and performs certain tasks.The aim was to understand how kids respond to different colours and visuals. Hence, kids were asked to separate different shapes as per their colour and size, generated by computer which popped up from different sides of the screen. Results were surprising as bilingual children were more accurate than monolingual group. Study depicts that bilingual brain functions faster and has divergent thinking skills which allows brain to recognize and differentiate different objects at the same time. Therefore, bilingual children tend to be smarter than monolingual peers and perform cognitive tasks better. . 2 More Creative with Analytical Abilities A rese arch conducted by Dr Lauchlan in Scotland and Sardinia, Italy- 121 children under age of 9 were taken in a group with monolingual and bilingual abilities, and were asked to perform different mathematical, creative, linguistic and physical assignments. The emphasis was to evaluate how children respond to different tasks. The bilingual learner’s performance and intellectual capabilities were significantly higher i. e. (52%) than monolingual peers (48%) (Refer figure 1. 2) Page | 2Figure 1. 2 Pie chart adapted from data provided by Dr Strathclyde research. 1. 3 Greater Success Rate There has been sufficient evidence, which reveals that bilingualism is an asset, as it provides higher employment rates over monolingual person. As stated in 2006 Canadian census, knowledge of French and English provide more job opportunities as compared to knowledge of French or English alone. Refer to the following graph (figure 3. 3) Fi gure 3. 3 Page | 3 It is apparent from the graph that bilingua l people have higher job prospects.This is an era of globalization, where most of the organizations are multinational. Hence, organizations prefer to hire employees who are proficient in different languages and understand diverse cultures. 1. 4 Brain Development â€Å"Children who learn a second language before the age of five have been shown to have denser grey matter in their brains than their monolingual peers† (Dai, 2012). According to Cumming (2005) research shows brain has two prominent tissues visible to eyes known as white and grey matter. Source: Mechelli, A. Nature, October 2004; vol 431: p 757.In 2004 research conducted by Dr Mechelli and his team at University College, London, revealed similar results. During their research they evaluated brains of monolingual and bilingual people who were introduced to second language early in their life. One set of group started learning second language at the age of 2 and another people were introduced to new language at the ag e of 30. The study reveals, those who initiated learning second language early had better command and proficiency in second language. Furthermore, density of grey matter on the left side of their brain was higher. Grey matter is combination of â€Å"head† nerves functions for coordination and communication) Conclusions: It is apparent that children who start learning in two languages at early age have cognitive and linguistic benefits over children who are mono-linguistic. Also, it prepares children for future to get better employment. Diversity comes naturally to bilingual children as it helps them to grow, understand different aspects of life and prepares them to adjust in multicultural environment, as they imbibe certain characteristics during the course of time.Due to these characteristics it makes children smarter and more confident as they learn in two languages. Page | 4 Recommendations: ? Canadian kindergarten school should work on integrated marketing methodology to lure and educate parents on the benefits of bilingual education. Publicise print ads in newspaper, magazines and different educational websites focusing on curriculum inculcated by school, to ensure their focus is to flourish analytical and cognitive skills of kids while they learn two languages as bilingual kids tend to become sharper day by day. ? School should conduct ducational fairs near school vicinity to provide information and familiarise parents about bilingual education. Especially for a strong economy like Canada where people are expected to speak two languages. When children are introduced to second languages early in their life they learn quickly, master the art of language and become proficient as they are agile and creative. ? Prospective parents should be invited for personal webinar and chat sessions on school website. Prime focus should be on how dual language learning can transform kid’s life in a positive manner as it provides exposure to different culture and diversities.Perhaps, helps children later in their life for better employment opportunities. ? E-mailers and Direct mailers should be sent to parents emphasizing the fact that a child’s brain grows faster with bilingual education . Also, it builds analytical, mental, linguistic and creative skills by allowing brain to respond to two different languages. Page | 5 References 1. â€Å"Bilingual children ‘better at problem-solving skills† 2012, Scotland (UK),United Kingdom, Scotland, viewed on 24th Nov 2012, ; http://www. bbc. co. uk/news/uk-scotland-glasgow-west-19109883; 2. 3.CummingW(2005),† The capacity of the brain in learning multiple languages†, London Sage Dai, A,2012, It’s a Small World After All from, viewed 23 rd Nov 2012 http://www. thethunderproject. org/its-a-small-world-after-all/#more-1053 4. Genesee, F 2004, ‘What do we know about bilingual education for majority language students? ’, in TK Bhatia & W Ritchie (eds ), Handbook of bilingualism and multiculturalism, Blackwell, Malden, pp. 547576. 5. Hitti ,M,2004,†Being Bilingual Boosts Brain Power† MDHelth news, viewed 25 th Nov 2012 6. Lowry ,L, â€Å"Are Two Languages Better than One†, The Hanen Centre, viewed 24 th Nov 2012, ; http://www. anen. org/Helpful-Info/Our-Views-on-the-News/Are-Two-Languages-Better-Than-One. aspx; 7. â€Å"Language Learning and the Developing Brain† (1996, winter). Learning Languages, 1 (2), 17. 8. MarianV, Faroqi-Shah, Y, Kaushanskaya,M, H. K & & Sheng,L. 2009, â€Å"Bilingualism: Consequences for Language, Cognition, Development, and the Brain†, Asha Leader, vol. 14, no. 13,pp. 10-13, viewed 20th Nov 2012. 9. Mechelli, A. Nature, October 2004; vol 431: p 757 10. â€Å"The advantages of bilingualism in Canada† 2008, Canadian council on learning, viewed on 25 th Nov2012, Page | 6

Interpretation of “My Papa’s Wallet”

â€Å"My Papa’s Waltz† was written by Theodore Roethke, which is a stanza poem with 16 lines. The narrator of the poem seems to be a young child speaking about an experience with his drunken father. In this poem the father came home after a night of drinking. As the father enters the house he grabs the child by the wrist with his battered knuckles, which indicates that he works with his hands. Playfully knocking down the pans, the mother irritated gives them an unhappy frown. The rhyme scheme is as follows, breath/death, dizzy/easy, pans/countenance, shelf/itself, wrist/missed, knuckle/buckle, head/bed and shirt/dirt. It’s obvious that the rhyme scheme is abab/cdcd. The rhyming in this poem seems to imitate the ordered steps of the dance of the poem’s title. However, it serves to show up the joyfulness that a person thinks of with the waltz. There is alliteration in every stanza, except in the last stanza. â€Å"Waltzing was† has the recurring sound of the letter â€Å"w†, which has a calm sound (line number 4). There are other indications that the waltz sounds loud, but the alliteration makes waltzing sound calm and usual. Countenance/could† have the sound of the frequent â€Å"c† which is a stanza with an exact sound (7/8). â€Å"Hand that held† is similar to the first stanza, which has a caring sound, â€Å"hand†¦. held†, is a an extreme contrast with the battered knuckle and scraped ear (9). â€Å"The hand that held† is assonance. â€Å"Still clinging to your shirt† is another assonance. The word â€Å"romped† is a connotation of disruptiveness, which the dancing in the kitchen caused the utensils to fall from the shelf. The tone of the poem is joyful and playful, because it seems that the father and the son are having a great time. The five main images that appear in the poem are gustatory, aural, visual, tactile and olfactory. The gustatory image is â€Å"The whisky on you breather† which is indicating the whisky can be taste. The aural image is â€Å"We romped until the pans† indicating that the sound of the pans were so loud that the mother was upset. The visual image is â€Å"My mother’s countenance/Could not unfrown itself† which indicates the look on his mother’s face was full of anger. The olfactory image is also â€Å"The whisky on your breath† which indicates the child could smell the whisky coming from his breath. At every step you missed/My right ear scraped a buckle† meaning the father is enthusiastic as he is waltzing in a fast pace (11/12). The narrator doesn’t want the young boys ear to touch the buckle, so he used ‘you’ trying to say that the father purposely lost control. â€Å"Then waltzed me off to bed/Still clinging to your shirt† the father is showing the son that he cares about him by taking him to bed (15/16). He is also showing him that he loves immensely regardless of what his son thinks. In the son’s eyes his father is a hero and the behavior that went throughout the entire poem was full of love.