I choose milk as the food type I would investigate for microbial contamination from Farm to Fork.

Introduction I choose milk as the food type I would investigate for microbial contamination from 'Farm to Fork'. I choose milk because I live in a rural area and find that the raw versus pasteurised milk debate is a very topical and important debate, which is ongoing. Raw milk was banned from been sold in Ireland from 1997. I plan to investigate how microbial contamination occurs from before milking start until the milk is placed in the consumer's glass. I have chosen to in particular investigate how microbial contamination with E. Coli 0157:H7 occurs. I have chosen E. Coli 0157, as it has become known worldwide because of increased food poisoning outbreaks that are all extremely serious. I will show how a mastitis infection in a cow while she is being milked leads to a major increase in microbial contamination. From this proper handling and sanitisation on farms become important. I will also show how important the correct distribution and storage of milk is in reducing possible microbial contamination. Mastitis Mastitis is a bacterial infection, which causes an inflammation of the udder. Raw milk from cows with mastitis is heavily contaminated with bacteria. The most common bacteria found on the udder during the inflammation are E. Coli, S. Aureus and Enterobacter. There are 3 different classifications of mastitis . Contagious Mastitis. This is caused by bacteria,

  • Word count: 1680
  • Level: University Degree
  • Subject: Physical Sciences
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Support Drilling for Oil in ANWR

Support Drilling for Oil in ANWR Alaska had many hidden treasures but the most valuable treasure in Alaska is its liquid gold, or more commonly, oil. North America's largest oil field, located in Prudhoe Bay, have off-set an continuing debate between environmentalists and gas industries on whether to drill for oil or not in the Arctic National Wildlife Refuge (ANWR). Oil companies in the US have sought the right to drill for oil in ANWR. Many benefits of drilling that are believed have been stated. For every opposition a rational way or technique had been pointed out and looked into carefully. Exploration for oil in ANWR will really benefit both the Alaskans and the other nations especially the US. We should support drilling for oil in ANWR because not only will it boost income and state money, the damage will also be limited by the use of new technology and it will reduce the US dependence on oil making world oil prices drop. (McGowan, 2004) Most of the supporters of drilling for oil stated that environmental damage will be limited because of the practices and experience of Arctic operations for over twenty years. By using new efficient techniques, impact on the tundra and the wildlife will be minimal. From these high-tech modern drilling techniques, fewer drilling platforms will be built. Building the oil fields on gravel pads the permafrost underneath will be protected.

  • Word count: 786
  • Level: University Degree
  • Subject: Physical Sciences
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Environmental Chemistry of Aqueous Systems

Environmental Chemistry of Aqueous Systems . Introduction Water is an incredibly important part of our environment. * Biological systems cannot survive without it. The recently funded ESA programme, Darwin, which is to look for signs of life on planets from other Solar Systems targets water along with CO2 and O2 (detected as O3) as key indicators for life. * Evaporation and condensation of water allows the transport of heat within our atmosphere, ultimately driving the wind system, while currents in the oceans provide another means of heat transfer. * The oceans can hold gases in solution, supplying the atmosphere with gases and acting as a buffer against atmospheric change. * It is involved in the formation of OH radicals in the atmosphere, which clean up our atmosphere. Distribution of Water 97 % is in the oceans 2.4 % is in snow and the polar ice sheets 0.6 % is in rivers and freshwater lakes 0.001 % is present in the atmosphere Need to understand Clearly, there are aspects of physics beyond the scope of these lectures that need to be addressed; e.g., latent heat of evaporation, condensation and freezing; atmospheric circulation; ocean currents, etc. For this course, we need to understand the chemistry of species dissolved in water. Two aspects are important: * Natural water systems. Water hardness (Ca2+, Mg2+), pH of rain water (CO2), weathering of

  • Word count: 2224
  • Level: University Degree
  • Subject: Physical Sciences
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In this essay I am going to evaluate a range of sources that cover the topic of the impact of humans on ocean acidification and summarise the pros and cons of each source type.

4SSG1008 Geography Tutorials: Critical Thinking and Techniques Geography Tutorial Group G1 Submission Date: 17th October 2011 Assignment 1: Evaluation of Sources Topic: "the impact of humans on ocean acidification" Word Count: 1116 Introduction The term ocean acidification is used to describe the ongoing decrease in ocean pH caused by human CO2 emissions, such as the burning of fossil fuels (UK Ocean Acidification Research Programme, 2011). In this essay I am going to evaluate a range of sources that cover the topic of the impact of humans on ocean acidification and summarise the pros and cons of each source type. Discussion Articles published in peer-reviewed journals are considered to be of the highest quality. They must undergo a thorough review process, with multiple professional experts and reviewers involved. As a result of their expertise, data can be presented in a clear, factual and appropriate way. The use of peer review conveys a variety of opinions that can help remove any personal biases and at the same, highlight new ideas and innovation. The three journal articles I examined: (Hoegh-Guldberg et al., 2008), (Sponberg 2007), and Wood et al. (2008) have all been peer reviewed by both scientists and professionals in the field. For example, Hoegh-Guldberg et al. (2008) is reviewed by several named professionals as well as an anonymous reviewer. As a

  • Word count: 1784
  • Level: University Degree
  • Subject: Physical Sciences
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Determination Of The Valency Of Magnesium

Title : Determination of the Valency of Magnesium Objective: . To determine the stoichiometry of the magnesium 2. To study the quantitative relations between amounts of reactants and products of the reaction. Theory & Background : Stoichiometry is the study of the combination of elements in chemical reactions. Stoichiometry refers to the relative number of atoms of various elements found in a chemical substance and is often useful in characterizing a chemical reaction. The related term stoichiometric is often used in thermodynamics to refer to the "perfect mixture" of a fuel and air. Stoichiometry is often used to balance chemical equations. In this experimet, a known starting mass of magnesium and the measured collection of hydrogen gas will be used to determine the reaction stoichiometry. Stoichiometry rests upon the law of conservation of mass, the law of definite proportions and the law of multiple proportions. In general, chemical reactions combine in definite ratios of chemicals. Since chemical reactions can neither create nor destroy matter, nor transmute one element into another, the amount of each element must be the same throughout the overall reaction. This experiment determines the stoichiometry of a reaction of magnesium and hydrochloric acid(HCl). The relationship between moles of magnesium reacted and moles of hydrogen produced are plotted.

  • Word count: 2079
  • Level: University Degree
  • Subject: Physical Sciences
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Solid / Liquid Separation

Solid/Liquid Separation (under gravity) Thickeners Why? For the purposes of separating solids from liquids en masse rather than of solids classification, particularly in the colloidal region (<2µm), thickeners have several advantages over centrifuges. What? A thickener consists of a large (cylindrical) tank (often) with a broad conical section at the base, at the centre of which is an outlet pipe/valve assembly. The stream from this outlet is termed the underflow. Around the rim of the tank is a tray, rather like a gutter, into which clarified liquor (the overflow) flows (as a result of overspill from the rim). A set of slowly rotating mechanical rakes gently scour sediment and direct it to the underflow. Feed is introduced at the centre of the tank (and distributed across it) at some distance below the surface. How? Overview Cursory consideration of the mass balance for such a device indicates that all solids must leave via the underflow and must not therefore be presented with any opportunity to reach the (overflow at the) rim of the tank. The design must ensure this. At a given feed rate, the vertical flow velocity of liquid (both up and down) in the device will decrease as the area is increased and vice versa. In the upper part of the tank net downward motion of solids is reduced, but in the lower section it is increased - relative to a freely settling

  • Word count: 1777
  • Level: University Degree
  • Subject: Physical Sciences
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A 0.60 um film of silicon dioxide is to be etched with a buffered oxide etchant of etch rate 750 A min-1. Process data shows that the thickness may vary up to 10% and the etch rate may vary up to 15%.

Andy Somody 97300-6222 ENSC 495 Assignment #3 6-1). a). A 0.60 um film of silicon dioxide is to be etched with a buffered oxide etchant of etch rate 750 A min-1. Process data shows that the thickness may vary up to 10% and the etch rate may vary up to 15%. The maximum possible thickness of the silicon dioxide film is therefore 110% of its nominal value. Therefore, the maximum possible thickness of the silicon dioxide film can be determined through the following calculation: where zmax is the maximum possible thickness of the silicon dioxide film and znominal is the nominal thickness of the silicon dioxide film. Therefore, znominal = 0.60 um. Any number expressed as a percentage can alternatively be expressed as a decimal. For example, 110% can be expressed as 1.1. Using this decimal format, the above formula can be rewritten in the following manner: Substituting our previously determined value for znominal into the above formula yields: with significant figures applied Similarly, the minimum possible etch rate of the buffered oxide etchant is 85% of its nominal value. Therefore, the minimum possible etch rate of the buffered oxide etchant can be determined through the following calculation: where rmin is the minimum possible etch rate of the buffered oxide etchant and rnominal is the minimum possible etch rate of the buffered oxide etchant. Therefore, rnominal =

  • Word count: 13367
  • Level: University Degree
  • Subject: Physical Sciences
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As the world's expanding population burns large quantities of fossil fuels and simultaneously cuts down large expanses of forests worldwide, the concentrations of CO2 and other greenhouse gases are building up in the atmosphere.

As the world's expanding population burns large quantities of fossil fuels and simultaneously cuts down large expanses of forests worldwide, the concentrations of CO2 and other greenhouse gases are building up in the atmosphere. "The green house effect is the (imperfect) analogy used to explain the atmospheric phenomenon that keeps our planet warm enough to sustain life." There is mounting evidence that this shift in Earth's atmosphere will lead to global changes and potentially major climatic disruptions . The major concern is not that the greenhouse effect is real;"we wouldn't be here if it wasn't." It's that it "may be exacerbated by anthropogenic increases in the effective gasses, threatening a disruption to the equilibrium between incoming and outgoing energy, and a resulting average global warming." From 1880 to today, by many measurements, the global average temperature has increased by 0.5 Degrees Celsius. Human and ecological systems are already vulnerable to a range of environmental pressures, including climate extremes and variability. Global warming is likely to amplify the effects of other pressures and to disrupt our lives in numerous ways. "Melting icebergs and expanding oceans may cause floods." The Intergovernmental Panel on Climate Change (IPCC) predicts

  • Word count: 806
  • Level: University Degree
  • Subject: Physical Sciences
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Article reviewed: "The role of the physical and traffic environment in child pedestrian injuries." Pediatrics, Vol. 98, No. 6. December, 1996.

Critical Review Student Name: Julia PU Student No.: 30646723 Tutor's name: Dr Alan Jones Article reviewed: "The role of the physical and traffic environment in child pedestrian injuries." Pediatrics, Vol. 98, No. 6. December, 1996. Date of submission: Friday October 13th, 2000. Agran, Phyllis F.; Diane G. Winn; Craig L. Anderson; Cecile Tran; Celeste P. Del Valle. "The role of the physical and traffic environment in child pedestrian injuries." Pediatrics, Vol. 98, No. 6. December, 1996. Pedestrian injuries have always be a dominant threaten to parents as it would result in severe injury or death among younger children. Increasing, it has became not only a issue that concerns our community, but a important topic that gains large number of attention from the whole society. Scientist, phycologist and educators have put a great deal of effort on academic research in order to investigate the major causes of pedestrian injuries, and so that different approaches can be used to prevent childhood pedestrian injuries. While previous studies have focused on vehicle speed and traffic volume which associated with greater injury incidence, a group of scientists (including Phyllis F. Agran, Diane G. Winn, Craig L. Anderson, Cecile Tran and Celeste P. Del Valle) designed a case-control study for Latino children in southern California aged between 1 to 14 years old. The purpose of

  • Word count: 884
  • Level: University Degree
  • Subject: Physical Sciences
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Comparing the Energy Outputs of Different Fuels.

Comparing the Energy Outputs of Different Fuels. Aim To investigate the amount of energy released from different fuel sources and to compare respective costs of the fuels per kilo joule of energy transferred. Hypothesis I suggest the longer the hydro-carbon chain of the fuel being burnt the greater the energy released per gram of fuel burnt. However given the price of fuel per gram, typically, does not increase proportionately to the chain length, the fuel releasing the most energy may not necessarily be the most cost effective. Method Apparatus: * Copper beaker/can * Ceramic crucible (with lid) * Frame and clamp * Heat Proof Mats * Thermometer * Balance * Tin foil * Small lengths of string (to act as wicks) * Measuring cylinder * Distilled water * Selection of Fuels* *For this comparison -Methanol C H3 OH -Ethanol C2 H5 OH -Propanol C3 H7 OH -Butanol C4 H9 OH and -Candle Wax Procedure: .Start by setting measuring out 200ml of water, transfer to the copper beaker and take the water temperature. 2.Now clamp the beaker to the frame and adjust so that the bottom of the beaker is at a height exactly 4cm from the top of the crucible (when the crucible is directly under it). 3.Remove the crucible from its position, carefully pipette approximately 1g of methanol into it and replace the lid (this is to reduce any loss through evaporation).

  • Word count: 1497
  • Level: University Degree
  • Subject: Physical Sciences
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