High School Life Essay Example for Free

High School Life Essay High school is a place where young teens learn to become mature and responsible. It is a place where students get trained to take on bigger challenges in life. Obstacles such as college. From my own personal experiences, high school didnt seem that way. Students were more concerned about getting a passing grade then about what they were taught. They would even cheat their way out of high school. This would prepare them for college. My freshman year of high school, I was in a totally different place and it seemed quite interesting and fascinating at first. As the year passed by, I started to notice the techniques students were using to pass classes. It was something I didnt see while I was in junior high school. Students were cheating on almost all the tests. They would bring little print-out cheat sheets to class to use on the tests. Hardly anyone got caught by the teacher. When students did get caught, all they would do is deny and usually the teacher would just let them get away with it. As Casey Banas wrote in Why Students Are Turned Off? I sometimes estimated that half to two-thirds of a class cheated on a given test, Glanz said. Worse, Ive encountered students who feel no remorse about cheating but are annoyed that a teacher has confronted them on their actions (Banas 659). Cheating seemed like the popular thing to do and if you didnt cheat you would be considered real foolish.. Everyone in the class knew what was going on and it was basically a whole class effort to cheat. Students would discuss what the answers were before taking the test and give each other opinions on how to cheat safely. When the test came back, every student in the class would have a real close score, but the teachers didnt seem to notice anything at all. Most of the students that go into a certain class usually wouldnt even know what went on even after the class has ended. As Casey Banas wrote: The teacher is convinced that the subject matter is worth knowing, but the student may not agree. Many students, Glanz said, are not convinced they need to know what teachers teach; but they believe good grades are needed to get into college†¦.(Banas 659) These kids could literally just sit there for forty-five minutes daydreaming. I find that many students feel the classes are extremely boring and is of no use to them in the future. I always used to ask myself Why do I need to know this stuff for?. When students feel this way, they dont do the work because they dont think they need it in life. When I used to go to high school, my whole class would get assignments and home works and about almost three-fourths of the class didnt do it. Instead they would wait until someone who was paying attention and did do the assignment to come along and let them copy the assignment. They would do it in way that the teacher wouldnt even know by slightly changing some words here and there. After that, that paper gets passed around the entire class to the students who didnt do the assignment and everyone would have a slightly different paper. This way all the students hand in the assignment and will get a passing grade, but did they even learn anything?. These techniques that were used in the high school that I attended did work and a lot of students graduated from high school using these techniques. I, myself, used these techniques and got through my freshman year. As time went on I found that high school was really boring so I decided to cut and eventually dropped-out of school. These students got good grades and did all the assignments, but the truth is, they didnt learn much at all. They can have a 85 average and get into a good college, but will they be prepared enough to survive college level work? I dont think so.

Riparian Ecosystem in the Semi-arid Southwest US

Riparian Ecosystem in the Semi-arid Southwest US Yi Rong Ecosystem project Geographic location The absolute location of the riparian ecosystem in the semi-arid Southwest of the US is 38 ° 11†² 21†³ S 109 ° 53 †²07 †³ W while its relative location is Southwest of the Colorado River. Climate The riparian ecosystem in this region registers an annual temperature of approximately 55F with an annual temperature range of 40F to 55F. The region receives a bi-modal precipitation regime with the highest precipitation experienced during the winter as well as during the summer monsoon winds. The annual precipitation can be recorded at between 16cm to 54cm. One of the major factors affecting the temperature and precipitation in this ecosystem is the proximity to the Colorado River which increases precipitation (Trexler 58). The thin cloud cover also influence the temperature as well as precipitation as it dictates the amount of direct sunlight on the moisture on the ground. The elevation of the ground is also another important factor that may influence precipitation and temperature. The higher the elevation, an area will experience higher the temperatures and lower precipitation. However, if the elevation is low then temperatures are expected to be lower while precipitation will be higher (Trexler 63). Extreme weather events in the southwest riparian ecosystem are mainly heat waves, floods and droughts and this can be attributed to the global climate change. This is because the climate of this region can be classified under a cold, semi-arid climatic zone (Doyle and Drew 13). This is characterized by relatively long drought periods as well as irregular precipitation, growing seasons that range from warm to hot and extended periods of winter which is sustained by freezing temperatures. Landforms and the land forming processes The riparian ecosystem here sits on a crustal rock that is surrounded by deformed Rocky Mountains together with Basin and Range Provinces (Raynolds 23). The main structures in this region are flexures, salt tectonic features, monoclines, vertical faults and volcanic. The folds here are broader rather than the characteristic tight folds found in orogenic belts. The wide areas of flat lying sedimentary rocks are divided by sudden bends of strata that form along the monoclonal folds formed nearly more than 600 million years ago. Normal faults dissect the ground in this area where normal faults are formed by tensional forces in which case the foot wall moves upwards relative to the hanging wall. These faults are more prevalent here because of the movement of the crustal blocks occurring in the Precambrian basement and the differential movement can be attributed to the differences in the elevation in this particular riparian ecosystem (Raynolds 39). Precambrian rocks are visible around th e region and they consist of gneiss, schist and younger sedimentary rocks. About 1.7 billion years ago, a north-south continental compression resulted in wrench faults areas, one being the Colorado River Lineament. Water and wind are the two key forces that can be attributed to the erosion of the ecosystem over the years (Adler 32). The main reason why water is the greatest force of the two is that the sun bakes the soil thereby making it so hard that it becomes difficult to absorb water. Therefore, when it rains, rain water flows freely with immense force. The vegetation in the area also doesn’t have deep laid roots to hold the soil together and this only adds to the problem (Lauenroth and Burke 51). As the free flowing water goes down, it creates flash floods that have great power to move rock boulders as big as automobiles. Ice also another erosion factor that cannot be ignored in this area. As faults are created between rocks, water seeps between these cracks and when temperatures are low, it turns to ice thereby expanding the cracks. When these faults get wide enough, pieces of rocks on the edges fall away and hit other rocks along the way thereby causing massive erosion effects. Th e topography of the ecosystem has characteristic different elevation levels. The vegetation in this area is mainly open-woodlands. The plants found here include cottonwoods, alders, cattails, plums as well as tall grass (Ralston 74). The Colorado River also makes an important part of the topography of the ecosystem. Surrounding the ecosystems are canyons and volcanic rocks whose surfaces have been eroded over the years mainly by water. Drainage patterns and stream systems The flow of the stream determines the forces that erode sediment and transport and deposit the same. This is important as it influences the various dimensions of aquatic systems in the ecosystem (Raynolds 53). The variance of stream flow also plays a major role in the occurrence of suitable environment and species abundance. The structural controls offered by the environment in the ecosystem act to dictate the various aspects of the stream’s flow such as its velocity and direction. Drainage patterns of streams in the ecosystem take the form of parallel and dendritic drainage patterns that are the most common in riparian ecosystems. As for the stream capacity, given the geology of the ecosystems and the level of erosion, the stream capacity in the ecosystem is high as the sediments from eroded soil and rocks transported by the stream is also high which translates to high power (Hazel 47). However, stream discharge in the ecosystem is relatively low as the width of the stream is narrow and wouldn’t support high stream discharge while the stream velocity is also low due to the many artificial islands formed by rocks found in the stream. These act to reduce the velocity of the stream greatly. The hard soil surface under the stream makes it difficult for water absorption and therefore when it rains, flash floods form easily while recurrence depends on the rain intervals during the year. Biome The biome in the ecosystem is classified according to the latitude within which the ecosystem is located. As a result of this, the climatic conditions brought about by the ecosystem’s latitude play a major role in determining the biome found in this area. Therefore, the dominant plants found in this particular ecosystem are mainly cottonwoods and open-woodlands. The animal species are the mule deer and the elk (Van Cole 16). Ecosystem characteristics, productivity, and services The productivity of the ecosystem can be seen from the dams and reservoir built in order to reduce the amount of erosion taking place in the ecosystem (Yaffee 61). This has received positive results as erosion has reduced greatly. On productivity, the ecosystem acts as a park ecosystem and local tourists can go and enjoy the different flora and fauna the ecosystem has to offer. Habitat/s The Riparian habitats are defined by different plants that depend on an integral hydrological regime. It is a case whereby the groundwater is sustained and surface flows that are natural occur. Plant and animal communities An assemblage of animal and plant communities is what define Riparian ecosystems and the presence of these communities attribute directly or indirectly to stream induced or interrelated factors. A greater diversity of animals and plants are supported by the Riparian ecosystems than the upland habitats. Food web and food chains In relation to the food web and chains, it is clear that approximately 80 percent of sensitive vertebrate species depend on aquatic habitants in their life cycle. Example of an animal and its niche There are western screech-owls, which have a niche at the moist woodlands that are found along the lakes and streams. Example of a symbiotic relationships A significant symbiotic relationship is between the star-flowered Solomon’s-seal with the moist shady woodlands that are found along the streams. Human-Land relationships Deforestation and animal grazing are some of the human activities that are taking place in the ecosystem. Ecosystem status Currently, the ecosystem is in a threatened/endangered status as the acts of animal grazing and deforestation are rampant within the area. A practical conservation strategy that has been adopted is the Conservation Reserve Program, which has been redesigned with the purpose of providing priority to areas that are stream buffer zones. Works Cited Adler, Robert W. Restoring Colorado River Ecosystems: A Troubled Sense of Immensity. Washington: Island Press, 2007. Web. Bainbridge, David. A Guide for Desert and Dryland Restoration: New Hope for Arid Lands. Washington: Island Press. 2012. Print. Doyle, Mary, and Cynthia A. Drew. Large-scale Ecosystem Restoration: Five Case Studies from the United States. Washington: Island Press, 2008. Web. Folliott, Peter and Leonard F. DeBano. Riparian Areas of the Southwestern United States: Hydrology, Ecology, and Management. Florida: CRC Press. 2003. Print. Hazel, Joseph E. Monitoring Fine-Grained Sediment in the Colorado River Ecosystem, Arizona: Control Network. S.l.: Bibliogov, 2013. Print. Kaiser, James. Grand Canyon: the Complete Guide. Ringgold, Ga.: Destination Press, 2011. Print. Lauenroth, William K, and Ingrid C. Burke. Ecology of the Short grass Steppe: A Long-Term Perspective. Oxford: Oxford University Press, 2008. Web. Ralston, Barbara E. A Vegetation Database for the Colorado River Ecosystem from Glen Canyon Dam to the Western Boundary of Grand Canyon National Park, Arizona. Flagstaff, Ariz.: Northern Arizona University, 2007. Print. Raynolds, Robert G. Roaming the Rocky Mountains and Environs: Geological Field Trips. Boulder, Colo: Geological Society of America, 2008. Print. Trexler, Joel. Monitoring Ecosystems. Washington: Island Press. 2003. Print. Van, Riper C, and Mark K. Sogge. The Colorado Plateau Iii: Integrating Research and Resources Management for Effective Conservation. Tucson: University of Arizona Press, 2008. Print. Van, Riper C, and Kenneth L. Cole. The Colorado Plateau: Cultural, Biological, and Physical Research. Tucson: University of Arizona Press, 2004. Print. Yaffee, Steven L. Ecosystem Management in the United States: An Assessment of Current Experience. Washington, DC: Island Press, 1996. Print.

False Positives In Presumptive Blood Testing Biology Essay

False Positives In Presumptive Blood Testing Biology Essay Blood is a fluid medium that is found within the cardiovascular system-which comprises of the heart and blood vessels (Jackson and Jackson 2008). It consists of 55% blood plasma and 45% cellular material (Jackson and Jackson 2008). Blood plasma consists of dissolved materials such as antibodies, hormones, waste products and nutrients, whereas the cellular material consists of erythrocytes (red blood cells), leucocytes (white blood cells) and thrombocytes (platelets) (Jackson and Jackson 2008). Blood is transported through the body by the pumping action of the heart. It has numerous functions including (Jackson and Jackson 2008): Acting as an internal transport system-including the removal of waste products for excretion and moving nutrients for metabolism. Maintaining body temperature. Defending against infection. Protecting the body from effects of injury. Blood is one of main sources of DNA found at crime scenes, and is crucially important in establishing a link between a suspect and a victim of a crime (Jackson and Jackson, 2008). To detect the presence of blood at a crime scene, a presumptive test is used. These can, however, only detect whether a substance is blood and cannot distinguish between human and animal blood-a serological test is needed to do this. The Erythrocytes (red blood cells) are the most common type of blood cell and contain haemoglobin (Jackson and Jackson 2008). They contain haemoglobin- a protein containing iron. Haemoglobin is responsible for the carriage of oxygen, and it is this property that presumptive blood tests are based on. Most of the presumptive tests rely on the ability of haemoglobin to catalyse the oxidation of a reagent, normally hydrogen peroxide (H2O2 (aq)) (Jackson and Jackson 2008). The result of oxidation normally produces a colour change in the presumptive test. Tiny amounts of blood present as a scene can be detecting using a colour change test. Some old and dried stains look similar in appearance to blood which can lead to a scenes of crime officer conducting a presumptive test. Other substances that could have contaminated suspected blood or other substances on their own at a scene could lead to a presumptive blood test incorrectly showing a positive result for blood. This is known as a false positive. Once a stain has been determined as blood, then two processes must be completed. The first is to interpret any bloodstain patterns, so that a reconstruction of events can be established (Langford et al 2005). Secondly, bloodstains must then be recovered for further analysis (Langford et al 2005). Recovery of bloodstains varies according to whether the stain is wet or dry. Once recovered, the blood can then be sent to a Forensic Science Service laboratory, where it will be initially tested to ascertain whether it is human or animal blood. To do this a serological test will be conducted, which involves identifying the presence of proteins specific to humans and analysing for DNA sequences specific to humans (Jackson and Jackson 2008). The blood will then be used for DNA profiling, which will hopefully establish whether the blood belongs to the suspect or the victim. I.II Aims and Objectives The aim of my project is to create a definitive list of false positives for four different presumptive blood tests. Within this aim I have six objectives to complete: To compare the false positives of four different presumptive tests. To test substances that are known false positives- as reported by other authors. To test unknown substances allied to those already known. To record the time taken for a substance to react with a presumptive test. To photograph the results of from each substance. To create a definitive list of false positives for each presumptive test. I am going to compare four different presumptive tests, as some tests are more practical to use in some situations than others. Consequently, analysing more than one test will allow a wider range of results. I shall also be testing known false positives as reported by other authors, as it is important to show how the presumptive tests react. Unknown substances allied to those that are known will then be tested to see whether similar substances react alike. This will then allow me to establish whether an unknown substance has reacted or not, as I can compare the reaction times and colour changes from both the known and unknown substances. It is important to record the time taken for a substance to react with a presumptive test, as blood should show a result straight away. An unobvious result that takes time to develop could indicate that the substance being tested is a false positive. Photographing results will allow me to document the differences in the colour change in each reaction with each substance. I feel that it is important to create a definitive list of false positives as it can reduce the risk of using valuable resources at a crime scene. For example, if a scenes of crime officer is informed that a possible blood stain has been contaminated with horseradish (a known false positive), then they can use a presumptive test for blood that is not known to produce a false positive with horseradish. If the result is positive for blood, then serological tests for blood can be carried out. Overall, I hope that this project will aid the work of a scenes of crime officer to choose the correct presumptive test to use in different situations-minimising time spent and resources used. Chapter II. Literature Review II.I Background Information The scientific analysis of blood was initially mentioned in 13th century Chinese texts, but it was Karl Landsteiner who discovered the modern science of blood typing, which categorises different types of blood into the ABO blood typing system (White 2010). In 1901 it was reported that blood could be determined in two week old serum stains on linen, and by 1902 the four blood types A, B, O and AB had been discovered (White 2010). This system is based on types of antigen on the red blood cells membrane. An antigen is a protein molecule capable of binding on to an antibody (Erzinà §lioglu 2004). The ABO system uses two antigens which are known as A and B; and the four blood groups are determined according to this system (Erzinà §lioglu 2004). People that have the blood group A have the A antigen, those that are group B have the B antigen; those in the AB category have both antigens and those who belong to the O group have neither antigen (Erzinà §lioglu 2004). A persons blood contai ns the opposite group of corresponding antibodies, so people with blood group A have b antibodies, people with blood group B have a antibodies, those with blood group AB have neither a or b antibodies and those with blood group O have both a and b antibodies (Erzinà §lioglu 2004). If the wrong antibodies are introduced into the wrong blood group then death can be a result due to the red cells clumping together. The first suspect to have been convicted largely on the basis of DNA analysis of blood samples was found guilty at Leicester Crown Court on 22nd January 1988 (White 2010). This case marks an important milestone, and DNA technology has become commonplace in forensic laboratories and is now instrumental in establishing both guilt and innocence in court cases (White 2010). II.II Physical Properties of Blood Blood constitutes about 7.7% of the body weight of a person (White 2010). This equates to 5-6 litres in males and 4-5 litres in females (Tortora and Anagnostakos 1987). Viscosity is resistance to flow, which in fluids is compared to water which has a viscosity of 1. (Bevel and Gardner 2002). Blood viscosity usually ranges between 4.4 and 4.7 (Tortora and Anagnostakos 1987). Blood also has a higher specific gravity (density) than water, which is the weight of a substance relative to the weight of an equal volume of water (James and Nordby 2005). Blood is a fluid that circulates throughout the body by way of the heart, arteries, veins and capillaries-known as the circulatory system (James and Nordby 2005). A primary function of blood is to transport oxygen, electrolytes, nourishment, hormones, vitamins and antibodies to tissues and to transport waste products from tissues to the excretory organs (James and Nordby 2005). Tortora and Anagnostakos (1987) (in Bevel and Gardner 2002) say that when 4-6 litres of blood is present in the circulatory system, it is distributed as follows: Figure 1- Blood Distribution in the Circulatory System (Tortora and Anagnostakos 1987) As a medium, blood is composed of 55% plasma and 45% cells (White 2010). A single drop or large volume of blood is held together by strong cohesive molecular forces that produce a surface tension (James and Nordby 2005). Surface tension is defined as the force that pulls the surface molecules of a liquid toward its interior, decreasing the surface area and causing the liquid to resist penetration (James and Nordby 2005). Bevel and Gardner (2002) state that plasma is the pale yellow fluid component of blood, which is broken down by volume into 91% water, 8% protein, 1% organic acids and 1% salts. Fibrinogen is one of the proteins, and this plays an important role in the clotting of blood (Bevel and Gardner 2002). Blood serum is blood plasma minus its protein content (Jackson and Jackson 2008). The cellular component of blood consists of erythrocytes (red blood cells), leukocytes (white blood cells) and thrombocytes (platelets) (Bevel and Gardner 2002). Red blood cells are heavier than plasma, which can be seen in bodies as lividity-which is where red cells settle to the lowest extremity of a body after death (Chmiel and Walitza 1980). http://people.eku.edu/ritchisong/301images/Red_White_Blood_cells.jpg Figure 2- A red blood cell, platelet and white blood cell (University of Eastern Kentucky 2010). There are roughly 4.8 to 5.4 million red blood cells per cubic millimetre of blood (Tortora and Anagnostakos 1987). They are bioconcaved discs in shape. The main role of the red blood cells is to transport oxygen from the lungs via the arterial system and return carbon dioxide to the lungs for expiration via the venous system (James and Nordby 2005). Red blood cells contain haemoglobin which is a red pigment that gives blood its colour (Bevel and Gardner 2002). Haemoglobin is composed of globin, which is made up of four folded polypeptide chains, and four haem groups that join with iron (University of Eastern Kentucky 2010). http://www.ul.ie/~childsp/CinA/Issue64/Images/TOC36_2.gif Figure 3- Haemoglobin, containing four haem groups (University of Limerick, 2010). As the oxygen content increases in the blood, the bright red pigment of the haemoglobin also increases (Bevel and Gardner 2002). A red blood cell does not contain a nucleus. Red blood cells are expressed as a percentage of the packed (red) cell volume (PCV), also known as the haematocrit (Wonder 2001). Nelson and Rodak (1983) state that the haematocrit in humans is variable between individuals. Haematocrit Possible people with range of haematocrit 15-29% Chronic alcoholics or drug abusers, steroid abusers, women after traumatic child birth or illegal abortion, malnourished homeless, elderly. 30-48% Normal range for nontraumatic venipuncture (blood drawn in a clinic or hospital) samples. 49-75% Dehydrated individuals, people in shock, those living at high altitude, impending and active heart attack victims, newborn babies, people suffering from hypothermia, and people after extreme exercise. Table 1- Table to show the range of haematocrit ratios (Wonder 2001). White blood cells act to fight infections, destroy old cellular material and to destroy other invading microbes (Bevel and Gardner 2002). White blood cells can be further subdivided into phagocytes which are responsible for the capture and ingestion and foreign substances, and lymphocytes- which are responsible for the production of antibodies (Jackson and Jackson 2008). They make up less than 1% of the cellular component of blood, which equates to 5000 to 9000 white blood cells per cubic millimetre (Tortora and Anagnostakos 1987). The nuclei of white blood cells are the source of DNA in the blood (James and Nordby 2005). The other part of the cellular component of blood is the platelets. Like red blood cells, platelets also lack a nucleus (Bevel and Gardner 2002). Bevel and Gardner (2002) say that there are generally about 250,000 to 400,000 platelets per cubic millimetre of blood. Platelets are major components of the clotting mechanism of blood, and this is their primary function (James and Nordby 2005). Platelets have irregular shapes and are normally quite small, however when they encounter a damaged blood vessel they increase their size and their shapes changes (Bevel and Gardner 2002). They also become sticky and adhere to surrounding fibres in the vessel wall, which results in the accumulation of platelets called the platelet plug (Bevel and Gardner 2002). II.III Blood at a Crime Scene Blood is normally found at a crime scene due to a person sustaining an injury either by accident or on purpose. When a breach in the circulatory system occurs- due to an injury- the body reacts in different ways to control the loss of blood (Bevel and Gardner 2002). Initially the vascular spasm occurs, which is which the smooth vessels in the blood vessel wall contract to decrease the size of the vessel, which reduces the flow of blood through it (Bevel and Gardner 2002). Tortora and Anagnostakos (1987) say that this reduces blood loss for up to 30 minutes following injury, which gives time for the other blood loss mechanisms to engage. The platelet plug then follows which reduces, if not stops, the blood loss (Bevel and Gardner 2002). The final step is coagulation, or clotting. This is what is normally seen at crime scenes, where the clotted mass of fibrin fibres and blood cells is surrounded by blood serum (Bevel and Gardner 2002). There are three types of bleeding that can occur from damage to blood vessels (BUPA 2009): Arterial Bleeding Venous Bleeding Capillary Bleeding. Arterial bleeding usually is spurting bright red blood, due to the blood having come from the heart and lungs-so it is oxygen rich (Walter et al 2004). The pumping action of the heart adds rhythmic surges to move blood vessels away from the heart (Wonder 2001). It is the most serious type of bleeding, and the most difficult to control due to the blood in the arteries being under pressure from the heart (Walter et al 2004). Arterial wounds results in volume stains (Wonder 2001). Loss from the carotid artery or the aorta can rapidly lead to death (Wonder 2001). Examples of arterial injuries, and how they may occur are listed in Table 2. Artery Location Probable Occurrence Facial Mouth/lips Beating Temporal Head/temples Gunshot, Crushing Carotid Neck, front throat Stab wound, Gunshot, Decapitation Subclavian Under collar bone Gunshot, Crushing Aorta Chest Gunshot, Stab wound Brachial Arm/elbow Bone break Radial Wrist Slit wrists, Bone Break, Stab wound Femoral Groin Gunshot, Stab wound Tibial Ankle Bone Break, Crushing Deltoid Upper arm muscle Stab wound Table 2- Areas and actions that may involve arterial damage (Wonder 2001) External venous bleeding is normally as a result of wounding, as veins are closer to the skin than arteries (Walter et al 2004). It results in the steady flow of dark red (almost brown) blood, and is darker than arterial blood as it has released oxygen to the tissues in the body and is flowing back to the heart and lungs for more oxygen (Walter et al 2004). Capillary wounding is common in minor wounds as capillaries are very small vessels that are under very little pressure with a low volume of blood (Walter et al 2004). Capillary bleeding results in the oozing of either bright or dark red blood, which will normally stop on its own (Walter et al 2004). As well as the three main types of bleeding, there is a further category which is traumatic bleeding. There are different types of wounds which can cause traumatic bleeding, and these can be categorised as follows: Abrasion- also known as a graze, where an object brushes on the skin but does not break it. Hematoma- where blood vessels are damaged, causing blood to collect under the skin. Laceration- where a blunt impact to soft tissue causes a deep wound. Incision- where a precise cut is made into the skin. Puncture Wound- where an object penetrates the skin and deeper layers. Contusion- also known as a bruise, where a blunt trauma causes damage under the skin, but does not break it. Crushing injuries- where a great amount of force is applied over a period of time, causing initially internal bleeding. Ballistic trauma- where a projectile weapon has entered and exited the area of the body, causing a wound between the two. Scenes of Crime officers attend many types of crime scene where blood is present. These include: Burglary- When an offender breaks a glass window or door to gain entry to a premises, they risk cutting their hands/arms. This leads to blood being left on fragments of glass in the window and on the floor. Assault/Wounding- Open wounds are normally the result of an attack on a victim. Blood can be left at an assault scene on the weapon that was used in the assault, on the ground, on the offender and on the victim. If the victim is bleeding heavily then blood will be left whenever the victim comes into contact with another surface. Manslaughter/Attempted Murder/Murder- Blood left at these scenes is not only important for swabbing purposes, but the pattern in which the blood is left can determine the order of events at a major scene. Road Traffic Crash- Blood at this scene can be found in the victims car and, if involved, the offenders car. This is important as it can place people in their respective cars- allowing investigators to work out the positions of people at the time of the incident. The collection, packaging and preservation of blood evidence at a crime scene should not take place until the scenes of crime officer has documented the bloodstain patterns (Lee, Palmbach and Miller 2001). Whenever biological fluids are encountered at a crime scene, protective clothing, gloves and masks should be worn due to the biohazard nature of blood (Lee, Palmbach and Miller 2001). To recover dry blood, an area near the blood that is unstained should be swabbed using a sterile swab, as a control sample (Derbyshire Constabulary 2008). Then, the stain should be swabbed using a sterile swab that has been moistened using sterile water (Derbyshire Constabulary 2008). The remains of the stain should then be dry swabbed using a sterile swab (Derbyshire Constabulary 2008). The swabs should be returned to their tubes immediately and stored frozen as soon as possible (Derbyshire Constabulary 2008). A batch control of both the water and swabs should always be made, and should be exhibited separately to the swabbed stain and background control (Derbyshire Constabulary 2008). Items that have areas of dried blood on them should be packaged in paper bags which are sealed securely and clearly marked as biohazard. Blood and bloodstained evidence should never be packaged in airtight containers (Lee, Palmbach and Miller 2001). To recover wet blood, a control swab of the surrounding area of the stain should be taken using a sterile swab (Derbyshire Constabulary 2008). The wet stain should then be swabbed using a dry, sterile swab (Derbyshire Constabulary 2008). The swabs should be returned to their tubes immediately, and should be stored frozen as soon as possible (Derbyshire Constabulary 2008). Again, a batch control of the swab should be exhibited separately (Derbyshire Constabulary 2008). If a removable item has an area of wet blood on it, then the entire object should be exhibited and left to dry in a drying room at the police station. Often at crime scenes, stains that are composed of unknown substances can easily be confused with blood. Identifying whether a substance is blood allows further analysis to confirm species, and the individual (Spalding 2006). II.IV Presumptive Tests for Blood James and Nordby (2005) say that a presumptive test is one which allows the scenes of crime officer to make a qualified conclusion that blood is present in the tested sample, when positive. They also say that when a test is negative, stains that need no further consideration are eliminated. Presumptive tests may be recognised as those that produce a visible colour reaction or those that result in the release of light (James and Nordby 2005). Both of these rely on the catalytic properties of blood to drive the reaction (James and Nordby 2005). Lee, Palmbach and Miller (2001) write this as a chemical reaction: AH2 + H2O2 Æ’Â   A + 2H2O Oxidisable chemical Hydrogen peroxide Haeme Oxidised (colourless) (peroxidise) James and Nordby (2005) state that catalytic tests involve the chemical oxidation of a chromogenic substance by an oxidising agent catalyzed by the presence of blood. They also say that the catalyst of the reaction is the peroxidise-like activity of the haeme group of haemoglobin. Cox (2004) describes the attributes that a good presumptive test for blood should be sensitive, specific, quick, simple and safe. In order for presumptive tests for blood to function properly, they must detect a component of blood (Tobe, Watson and Daà ©id 2007). Most presumptive tests therefore act on the peroxidise activity of haemoglobin. This component is not found in the everyday environment, but other substances found in items such as fruit and vegetables perform a similar function (Tobe, Watson and Daà ©id 2007). A very popular presumptive method is the phenolphthalein test, which is also known as the Kastle- Meyer test (Virkler and Lednev 2009). Lee, Palmbach and Miller (2001) say that the Kastle-Meyer test was introduced in 1901 by Kastle. Phenolphthalein will cause an alkaline solution to turn pink after it has been oxidised by peroxide when blood is present (Spalding 2006). The reagent consists of reduced phenolphthalein in alkaline solution, which is oxidised by peroxide in the presence of haemoglobin (James and Nordby 2005). The test result is normally immediate, and a positive result a minute or more after the test is performed is usually not considered as reliable (James and Nordby 2005). It has a sensitivity of 1:100,000 (Lee, Palmbach and Miller 2001). James and Nordby (2005) say that Adler and Adler in 1904 investigated the reduced or colourless form (leuco) of the dye malachite green, which is also referred to as McPhails reagent. This test involves the Leuco base of malachite green (Lillie 1969). Leucomalachite Green oxidation is catalyzed by haeme to produce a green colour (James and Nordby 2005). The reaction is usually carried out in an acid medium with hydrogen peroxide as the oxidiser (James and Nordby 2005). It has a sensitivity of 1: 20,000 (Lee, Palmbach and Miller 2001). Bluestar is a luminol preparation developed by Professor Loic Blum in France that is extremely sensitive and stable and produces a very bright, long lasting chemiluminescence (James and Nordby 2005). The extreme sensitivity of Bluestar Forensic allows detections of bloodstains down to 1:10,000 dilutions (Bluestar Forensic 2004). It does not require total darkness to be visible, and works well on either fresh blood or old bloodstains (Bluestar Forensic 2004). Bluestar works by mixing the Bluestar Forensic solution with Bluestar Forensic tablets, which is then left to dissolve. This is sprayed onto the area of suspected blood. A positive result will cause a bluish luminescence (Bluestar Forensic 2004). The Hemastix test, created by Miles Laboratories in 1992, is particularly useful when solutions can be hazardous, or inconvenient (James and Nordby 2005). The test consists of a plastic strip with a reagent treated filter tab at one end (James and Nordby 2005). The tab contains TMB, diisopropylbenzene, dihydroperoxide, buffering materials and non reactants (James and Nordby 2005). A bloodstain is tested by moistening a swab with distilled water, sampling the stain, and touching the swab onto the reagent tab on the strip (James and Nordby 2005). The tab is normally yellow, and turns form orange to green or blue when positive. Quality control testing is necessary and should be completed with known blood samples on every new batch of test reagents to verify that the reagents are working as expected (Lee, Palmbach and Miller 2001). II.V False Positives Sutton (1999) points out that a false positive is an apparent positive test result obtained with a substance other than blood. James and Nordby (2005) say that misleading results can be attributed to Chemical oxidants (often producing a reaction before the application of peroxide) Plant materials (vegetable peroxidises are thermolabile) Materials of animal origin (that contain traces of blood). Substances that produce false positives generally take detectably longer to react and, therefore, may be eliminated through observational interpretation (Tobe, Watson and Daà ©id 2007). False positives were initially noted only with copper salts (Glaister 1926). Tobe, Watson and Daà ©id (2007) state that saliva, semen, potato, tomato, tomato sauce, tomato sauce with meat, red onion, red kidney bean, horseradish, 0.1 ascorbic acid, 5% bleach, 10% cupric sulphate, 10% ferric sulphate and 10% nickel chloride are all known false positives. Bluestar False Positives (2008) say that Bluestar has false positives that include oil based paint, alkyd varnish, turnip, banana, leek, green bean, carrot, ginger, manganese sulphate, copper sulphate, iron sulphate and potassium permanganate. Lee, Palmbach and Miller (2001) write that many household cleaning products contain oxidising agents that can produce false positives. Many fruit and vegetables produce false positives including apples, horseradish and broccoli (Lee, Palmbach and Miller 2001). Bleach is a false positive that provides an (immediate and intense reaction) according to Gardner (2005). Hunt et al (1960) say that faeces often gave a false positive depending on the food that had been eaten previously. Ponce and Pascual (1999) state that lemon juice added to a bloodstain can cause a positive result due to its acidity. A false negative is when there is some interference with the oxidation-reduction reaction, normally in the presence of a strong reducing agent, which results in a delay of the oxidation reaction; thus resulting in a coloured formation (Lee, Palmbach and Miller 2001). False negatives are less common but problematic as an actual blood sample may be overlooked or left at the scene (Lee, Palmbach and Miller 2001). Many of the false positive reactions can be identified during the presumptive testing procedure if any changes observed and the exact point in the reaction of these changes is recorded and compared to that of blood (Lee, Palmbach and Miller 2001). Chapter III. Experimental Methodology I will be investigating known substances previously reported by other authors that show a false positive and then analysing other substances similar to those already known to see if these also produce a false positive. III.I Project Design Each of the substances will need to be repeated to ensure a wide enough range of consistent results. Therefore, a grid will be drawn on a piece of Perspex measuring 1.5m2, and a piece of filter paper placed in each of the grid spaces, to allow the even distribution of substances and to allow the easy identification of false positives. Blood Known False Positives Unknowns 1 2 3 1 2 A New technique to detect metabolites from a single drop of blood B New technique to detect metabolites from a single drop of blood C New technique to detect metabolites from a single drop of blood Figure 4- A diagram to illustrate an example of the project layout. For each of the presumptive reagents tested, the filter paper in each grid space will be exposed to a substance to be tested. This will be allowed to dry for a minimum of 1 hour. Each substance will then be tested with a reagent. Each substance will be repeated three times to give a fair indication of performance. The time taken for a substance to register a positive result will be recorded. If a colour change occurs then the test will be classed as positive. If no colour change is noted within 5 minutes of the reagent being added, then the test will be classed as negative. III.II Sample Preparation The substances that I have chosen to analyse are known false positives as reported by other authors and then substances allied to known false positives. Known false positives to be tested: Horseradish. Tomato Sauce. Red Onion. Turnip. Lemon Juice. Bleach Solution (5%). Unknown substances to be tested: Brown Sauce. BBQ Sauce. Radish. Dark Chocolate. Orange Juice. Bleach Solution (less than 5%). III.III Choice of Presumptive Tests I have chosen to use the following presumptive reagents to test substances for false positives: Kastle-Meyer. Hemastix. McPhails. Bluestar. III.IV Control Tests I will test all of the presumptive tests on blank filter paper before proceeding to test with substances. This ensures that there is no reaction from the filter paper to the presumptive tests. I shall also test all of the presumptive tests with horse blood before proceeding to test with substances. This shows that the tests do recognise a sample of blood. I have chosen to use 2.5g of each substance as I feel this is an amount that is representative of a stain at a scene. Blood is reported to have been diluted to 1:10000 in previous tests, and as this dilution has proved the most successful, I have chosen to use this dilution. REARRANGE + FINISH

Roman Entertainment :: essays research papers

Introduction   Ã‚  Ã‚  Ã‚  Ã‚  Ancient Romans, like the Greeks, loved entertainment. Their idea of entertainment was usually something involving death and drama. They liked to watch plays, watch gladiators, participate or watch games, and watch or participate in animal hunts. Colosseum Events   Ã‚  Ã‚  Ã‚  Ã‚  The Colosseum is a famous arena that’s still partly standing today. This arena could seat over 50,000 people. On hot days, a canopy was raised over the Colosseum to protect the viewers from the heat.   Ã‚  Ã‚  Ã‚  Ã‚  In the Colosseum, many events were held for the Romans to watch. Watching was free so that everyone could come. The events held almost always involved death and destruction. There were the gladiators, the feeding of people to lions, animals fighting animals, animal hunts, animal circus acts, and mock sea battles, where the Colosseum was flooded with water. The animals used in these events were kept below the Colosseum and an estimated 5,000 animals were killed the day the Colosseum opened. The animals were kept under the Colosseum. Gladiators   Ã‚  Ã‚  Ã‚  Ã‚  Gladiators are people who fight each other or wild animals for other people’s entertainment in ancient Rome. They usually fought in the Colosseum. People would gather from all over to see them fight until they die, since they usually didn’t survive. If a gladiator survived three to five years of fighting, he or she was released and allowed to go back home. Romans watched gladiators fight because they not only thought it entertaining, but also thought it would prepare them for war.   Ã‚  Ã‚  Ã‚  Ã‚  People did not usually volunteer to be gladiators. Gladiators were slaves, condemned criminals, or prisoners of war. Someone called a lanista, or owner of gladiators would purchase these people. However, a few free men volunteered to be gladiators, though this did not happen often. Depending on what the person did or who the person was, the gladiators had different training and weapons. For example, a criminal that had committed a capital crime fought weaponless, while a criminal who did not commit a capital crime had training in a private gladiator school.   Ã‚  Ã‚  Ã‚  Ã‚  In the private gladiator schools, gladiators trained every day and received medical attention and three meals a day to keep them healthy. They were allowed to pick the weapons and armor that best suited him or her. Different types of weapons resulted in different types of gladiators. The types of gladiators are: Andabatae, who wore helmets without eye holes, Catervarii, who fought not in pairs, but

Pollution Essays -- essays research papers

Pollution, contamination of Earth's environment with materials that interfere with human health, the quality of life, or the natural functioning of ecosystems (living organisms and their physical surroundings). Although some environmental pollution is a result of natural causes such as volcanic eruptions, most is caused by human activities. There are two main categories of polluting materials, or pollutants. Advertisement Biodegradable pollutants are materials, such as sewage, that rapidly decompose by natural processes. These pollutants become a problem when added to the environment faster than they can decompose (see Sewage Disposal). Nondegradable pollutants are materials that either do not decompose or decompose slowly in the natural environment. Once contamination occurs, it is difficult or impossible to remove these pollutants from the environment. Nondegradable compounds such as dichlorodiphenyltrichloroethane (DDT), dioxins, polychlorinated biphenyls (PCBs), and radioactive materials can reach dangerous levels of accumulation as they are passed up the food chain into the bodies of progressively larger animals. For example, molecules of toxic compounds may collect on the surface of aquatic plants without doing much damage to the plants. A small fish that grazes on these plants accumulates a high concentration of the toxin. Larger fish or other carnivores that eat the small fish will accumulate even greater, and possibly life-threatening, concentrations of the compound. This process is known as bioaccumulation. II. Impacts of PollutionPrint section Because humans are at the top of the food chain, they are particularly vulnerable to the effects of nondegradable pollutants. This was clearly illustrated in the 1950s and 1960s when residents living near Minamata Bay, Japan, developed nervous disorders, tremors, and paralysis in a mysterious epidemic. More than 400 people died before authorities discovered that a local industry had released mercury into Minamata Bay. This highly toxic element accumulated in the bodies of local fish and eventually in the bodies of people who consumed the fish. More recently research has revealed that many chemical pollutants, such as DDT and PCBs, mimic sex hormones and interfere with the human body's reproductive and developmental functions. These substances are known as endocrine disrupters. See Occupationa... ...es of excessive noise. Page 1 of 2 See an outline for this article. How to cite this article  © 1993-2001 Microsoft Corporation. All Rights Reserved. Advertisement Related Articles Air Pollution bioindicators of environmental damage More... Books Encarta recommends Search for books about Pollution at BarnesandNoble.com Periodicals Search for periodical articles about Pollution in Electric Library. Free registration required Encarta Training Center Search for courses and materials on Pollution Internet Search from MSN Search News from MSNBC Related Web Sites EPA: US Environmental Protection Agency Noise Pollution Clearinghouse More Details Also on Encarta 10 words you should know Qwest: managed solutions Also on MSN MSN Pets: facts about furry friends Real estate tips from HomeAdvisor Our Partners The Princeton Review Studentloan.com Encarta Reference Library Learn about our award-winning CD and DVD products Please rate Encarta's 1 2 3 4 5 -select a reason- Exactly what I needed Was too technical Didn't provide enough detail Was out of date article on this topic. Poor Excellent Main reason for your rating

Disease Research

The ten leading causes of death in the United States of America as of 2005 are heart diseases, malignant neoplasm, cerebrovascular disease, chronic lower respiratory disease, unintentional disease, diabetes mellitus, influenza and pneumonia, Alzheimer’s disease, nephritis and nephrosis, septicemia, intentional self-harm. I preferred diabetes mellitus because I think this kind of disease should be given much emphasis and attention from the government. Diabetes mellitus is a type of disease in the pancreatic area.In this disease, the pancreas does not properly generate insulin. When the body cannot generate enough insulin, hyperglycemia and other related disorders will occur in our metabolism. Diabetes can cause harm in other body organs when complications will arise. First of all, it causes damage to the kidneys which are responsible for the absorption of waste products in our body. Damaged kidneys then causes the end stage renal disease in which the kidneys are destroyed mutel y. This then causes the nephrons to worsen which leads to other diseases such as hepatitis to arise.When this happens, the person now has two or more diseases to worry about. Today, it is estimated that 20. 8 million Americans suffer from diabetes. Out of this 20. 8 million Americans, 6. 2 million are undiagnosed. When diabetes goes unnoticed, prevention and early treatment would be impossible. If diabetes is not treated properly, it will then lead to life-threatening complications as mentioned earlier. The World Health Organization (WHO) estimates that the disease will rise to more than 50% in the next 10 years if ignored.According to the United States National Diabetes Fact Sheet 2005, â€Å"Overall, the risk for death among people with diabetes is about twice that of people without diabetes of similar age. † (Centers for Disease Control and Prevention & American Diabetes Association, 2005) One major cause of diabetes is an individual’s diet. Since in the United Stat es most follow the â€Å"Western-style† diet in which almost everything is sweet (having lots of sugar in it), it is suggested that people should watch their diet more. However, there is little understanding of the mechanisms in diabetes at present.Unwatched diet may cause obesity which then causes some organs to become larger and cannot function properly (Giurini, Cook, & Cook, 2007). Thus, the government must pay their attention on funding research on diabetes because first, more than 20 million people in the US suffer diabetes at present and will increase in the next 10 years; second; most people do not know that they have diabetes; and third, diabetes causes complications and even death when not treated properly and continued unnoticed. People should be well-informed about diabetes so that they will know how to diagnose, prevent, and treat diabetes.   Reference: Centers for Disease Control and Prevention, & American Diabetes Association. (2005). United States National Diabetes Fact Sheet. Retrieved. from. Giurini, J. M., Cook, E. A., & Cook, J. J. (2007). Diabetes: the latest trends in glycemic control. Clin Podiatr Med Surg, 24(2), 159-189.   

The Italian Unification: Mazzini, Cavour and Garibaldi

Evaluate the relative importance of Mazzini, Cavour, and Garibaldi for the Italian Unification between 1848 and 1871 In order to achieve the unification the Italians had to go through a long struggle starting from 1830 and ending in 1871. Thanks to the leading of Mazzini, Cavour and Garibaldi, the Mediterranean peninsula was able to defeat its foreign enemies, especially the Austrian Empire, and create a united nation under the King of Piedmont, Viktor Emmanuel II.Although Mazzini was the starter of nationalism movements and aroused the spirits of many Italians, Cavour and Garibaldi were the two leaders who were able, both in their own way, to create a consolidated country. Giuseppe Mazzini was an Italian journalist and idealist that at the beginning of the 1830s was able to stimulate the people of the Italian peninsula to fight for freedom from Austria and for a creation of a nation. In his first years of revolutionary movements in the 1830s he was exiled from Italy, and moved to Sw itzerland to create a new movement, the Young Italy.This movement was different from the precedent Carbonari, that were less prepared and more violent, and it was made up by the middle class and as well as the working class and the peasants. Mazzini didn’t believe that Italy could be unified under a king, and thought that the best way of government was a republic, especially after the king Charles Albert refused his proposal to be at the head of the Unified Nation. Even though Mazzini’s supporters were defeated during a revolt in Piedmont, he was able to create an organize movement that had a great influence on the Italian Unification.Later in his life, Mazzini worked cooperating with Garibaldi, and together with him they made a lot of progress in the process of achieving their goal. Count Camillo Benso di Cavour was the diplomatic and political leader of the Italian Unification. Cavour was the mind and the brain of the Italian Unification, who created the political st rategies to defeat Austria. He was a noble man but had liberals ideas, and wanted to unite the country under the Kingdom of Piedmont, working with Viktor Emmanuel II.He was elected first in the Parliament under the rule of Charles Albert, and when he abdicated in favor of his son Viktor Emmanuel II, he was made Minister of Commerce and Agriculture in 1850, Minister of the Navy and Finance in 1851 and Prime Minister in 1852. Mazzini could be compared to Bismark, Prussia’s chancellor, because not only were they both very strategic and intelligent, but even because he modernized the Kingdom of Piedmont like Bismark had done in the German territories. With his domestic polices he created new banks, that made loans to middle class men to open businesses, that gave jobs to the working classes.The banks also made loans to businesses that wanted to create railroads so that Italy was modernized like the rest of Europe. He then facilitated the trading to gain industrial goods from Engl and and strengthen the army of Piedmont, in order to prepare it for war. Cavour used once again his diplomatic skills when he decided to support France and England in the Crimean War in 1854, where his troops won many battles. He then secretly met with Napoleon III in Plombieres, and signed a compact in which the French Emperor promised to support Italy in a war against Austria in exchange of the territories of Nice and Savoy.When the war broke out in 1859 though, Napoleon III, unexpectedly resigned and withdrew his troops, signing a peace contract in Villafranca with the Austrians. With his foreign and domestic policies, Cavour had created the opportunities and the circumstances for Italy to unite. If Cavour was the mind and the brain of the Italian Unification, Garibaldi was the heart of the movement. He was an idealist who believed, like Mazzini, that Italy had to be unified under a republic and without foreign aid.He became the leader of the unification when, with his troops, th e thousand red shirts, he conquered Sicily in 1860 sending away the Bourbon family and the king of the Two Sicilies, Ferdinand II. He conquered Naples, and marched up north, until he got to Rome, where the troops of the Kingdom of Piedmont waited for him. Even though he was a republican, he decided to hand out the territories he conquered to the king Viktor Emmanuel II, who was now the king of Italy. Venetia was still part of the Austrian Empire and Rome was still part of the papal state.Garibaldi then tried to conquer the Papal State but was defeated by the French troops and was exiled from Italy. He was able to escaped but failed again sending an army from Tuscany to Rome again. The Italian Kingdom was finally united when Venetia was handed to the Italian kingdom after the Austro-Prussian war, and Rome was invaded by the Italian troops in 1871 and the Pope was given sovereignty on the Vatican City. Garibaldi was able to send away the Bourbon family and to conquer the south of Ital y, and became one of the greatest military leaders of all times in Italy.Even though Mazzini was the starter of the Italian movement the Young Italy and rose the nationalism spirits of the Italians to initiate the process of the unification, the mind and the heart of the unification, Cavour and Garibaldi, were essential to the creation of a united nation. They both were able to use their qualities, one of being a diplomatic and smart men, while the other being a brave and romantic military leader, and together were able to defeat the Austrian and hand to the Piedmont king, Viktor Emmanuel II, the Italian Peninsula.