Ellsworth Huntington essays

Ellsworth Huntington essays Ellsworth Huntington was a geographer who studied human behavior. He began notice that people within the northern hemisphere where working harder than the people in the southern hemisphere. This when he began to first conceive a theory, which stated that any one who lived in the southern half of the world was genetically unable to work as hard as the people who live din the north. This theory was called environmental determinism. This theory has since been disproved however. This is due to the realization that the working conditions where less desirable in the south than the north. Ever since air conditioners and other things that help increase stamina and productivity have been invented, work is the south has increased dramatically so that it is if not equal, it is more productive ...

UN Security Council and World Order

UN Security Council and World Order Introduction After the world wars I and II, many leaders of the world saw the need of putting in place proper laws and institutions to govern the world in a manner that would make it very difficult for another world war to happen.Advertising We will write a custom essay sample on UN Security Council and World Order specifically for you for only $16.05 $11/page Learn More One of the key steps towards this direction was the establishment and strengthening of the United Nations, so that it could have the power and means of maintaining law and order in the world. This assignment is a discussion of how and why the United Nations, through the United Nations Security Council has been attempting to manage world order and why and how it has been unsuccessful. Discussion The term world order or new world order as its popularly known as, is used to refer to a bureaucratic system of governance of the world which advocates for global governance in disregard to traditiona l State sovereignty which advocates for national governance (Slaughter, 2005). The term has its history from what was referred to as â€Å"illuminati† which was the movement responsible for the French revolution as well as revolutions in Europe (Stauffer Williamson, 2005). Recently, new world order has taken the form of institutions which have global influence, appeal and presence like the United Nations and its affiliated institutions as well as the so called Breton wood institutions (Balogun, 2011). One of the key UN affiliated institutions which has been trying to propagate and manage the idea of world order is the United Nations Security Council, which is concerned with global security. The UN, through the UN Security Council has been in the fore front in attempts to have a world which is centralized in terms of governance, administration, justice as well as in terms of trade. The main idea behind the centralization of world’s governance is that such a world would be safer to live in, especially after the September 11 terror attacks on the United States. It is worth mentioning that the United States actually controls the Un Security Council due to its veto power. In fact, many international relations analysts have argued that there is actually no difference between the United States and the UN Security Council. A good example to illustrate this scenario is the US led invasion on Iraq in 2003, in which the Security Council was unable to prevent the US from doing the invasion, despite the fact that there were no enough justifications for the invasion.Advertising Looking for essay on international relations? Let's see if we can help you! Get your first paper with 15% OFF Learn More In its attempts to manage word order, the UN Security Council has been employing the strategy of carrot and a stick, in which countries of the world, especially the developing ones are given aid with strings attached. In some situations, they are required to relinquish part of their sovereignty to international bodies like the international criminal court and several other international treaties and conventions. Those counties which fail to comply are not only slapped with economic sanctions, but also military actions as well. Why the UN Security Council attempts have been unsuccessful The initial intention of establishing and maintaining world order was good. But due to the politics of domination between the rich and the poor nations of the world, the idea has been faced with enormous challenges, which have made the UN Security Council strain without much success in the management of word order. It seems that there has been a growing resistance to the new world order which attempts to concentrate resources and power around the ruling elite and the bureaucrats at the expense of the common persons or citizens commonly referred by Karl max as the have nots (Milanović, 2010). For instance, the recent uprisings in Arabic countries like Egypt, Libya and Tunisia were seen by many as an indication of civilian unrest and discontedment with the status of affairs in many countries which tend to pursue, propagate or support the ideology of a new world order. The unrest in these countries led to the ousting of the ruling bureaucrats, who had taken the advantage of the capitalist ideology to propagate inequality, lack of fairness and equity between various segments of the society which exists in form of social classes, with the upper social class enjoying the benefits of capitalism in form of surplus, as the low social class suffer from poverty, unemployment and lack of basic social amenities (Milanović, 2010). There have also been grassroots movements in form of civil society organizations which are formed by countries’ non-governmental sector. These civil society organizations have been working in a coordinated manner to push governments of countries to respect human rights, provide health care and education to the citizens. The idea behind the formation of civil society organizations is to empower the common citizens with information about their rights and the responsibilities of governments (Barlow, 2003) The universal declarations of human rights agitates for the universal respect of human rights, civil liberties and freedoms like the freedom of worship, movement and expression. These rights and civil liberties advocated for by the civil society have the potential of affecting the stability of the new world order, especially in the fight against terrorism, which is thought to succeed under the limitation of some of the civil liberties and political rights as stipulated in the United States Patriotic Act enacted after the terrorist attacks of United States in 2001 (Abele, 2005).Advertising We will write a custom essay sample on UN Security Council and World Order specifically for you for only $16.05 $11/page Learn More The international crimina l system of justice is intended to curb impunity and the violation of basic fundamental rights and freedoms of citizens. It is aimed at detaining and punishing leaders who violate the rights of their citizens. This has happened especially for countries like Rwanda, Yugoslavia among others. However, the court has been explained by many critics as being characterized by double standards between the rich and poor nations. The impact of the international court system on security is that many countries of the world are improving their political systems to become more democratic instead of dictatorial or authoritative. This to some extend has led to increased freedom of expression of citizens which in a way has reduced the grip of the rich nations on the power to control and manipulate the resources of the world. Economically, the grassroots movements have been able to lobby for increased opportunities for countries to do business with each other. The movements have also been very instrum ental in pushing governments to offer business opportunities and provide friendly loaning facilities to citizens. The world trade organization has been in the fore front in lobbying for increased interaction between nations in terms of doing business. It has also been working closely with individual governments to stream line their loaning facilities to be more friendly and accessible to many citizens (Barlow, 2003). The World Bank and the IMF have been working hand in hand with the world trade organization to offer financial support to the developing countries to fight poverty and disease, like Hiv/Aids and malaria. These institutions have empowered many poor countries to boost their levels of education, health care and overall, their economies. The economies of the poor countries have been improving from time to time, thereby reducing their dependency on the rich countries. This has been compromising the establishment of a new world order because the number of countries which may be manipulated for the gain of the rich countries is declining. Technologically, the grassroots movements and institutions have been working hand in hand with governments to be more open to technology transfer. Many countries of the world are now adopting the use of technology, especially the information communication technology like the use of the electronic mail, the use of the mobile phone networks as well as the use of electronic money transfer systems like wire transfer, money bookers, western union, PayPal among others (Chorafas, 1988).Advertising Looking for essay on international relations? Let's see if we can help you! Get your first paper with 15% OFF Learn More The use of information communication technology and the internet has enabled people to improve the way in which they communicate to each other in many sectors. In the trade sector, many people have been able to do business in various countries due to improved use of information and financial technology. Doing trade and business nowadays has become more efficient and convenient than ever, which has been advantageous to the economies of the poor or developing countries. In the education sector, information technology has opened up more opportunities for people to do research and improve their academic qualifications in a friendly, convenient and efficient manner. This has led to increased literacy levels in many countries, which has got a positive impact on the economy of many countries because many people are able to understand the nature of business transactions and how to undertake business in a sustainable manner. This has consequently worked against the establishment of the new w orld order in which the rich states are able to consolidate resources and opportunities at the expense of the poor countries. At the global level, the advancement in technology has been a growing concern especially the advancement of nuclear energy. Some emerging economies in Asia and Middle East are increasingly embracing nuclear technology as an alternative to the use of coal, crude oil and natural gas as sources of energy. The use of nuclear energy is presumed to be environmental friendly and to possess the ability to generate massive energy to power the growth of economies of countries of the world. However, the use of nuclear technology has been a growing concern to the United States especially in regard to the issue of misuse of nuclear technology. The fear is that nations like North Korea, Iran and Syria which are perceived as having a hidden agenda in their nuclear programs and described by the previous US president George W. Bush as â€Å"axis of evil† may use their nuclear technology to harm the United States, its allies and the world in general. Nuclear energy may lead to nuclear terrorism. It may also have serious negative implications on the environment especially in regard to the disposal of nuclear waste if not properly managed. All these nuclear related issues are perceived as working against the establishment and strengthening of the new world order in which the elite concentrate the possession of technology and even the energy used for boosting economic productivity in countries of the world. If the poor, emerging or developing economies are allowed to pursue nuclear energy, they will not only act as potential terrorist threats but would also act as serious competitors of the advanced economies like the United States and members of the European Union and the establishment of the new world order as well. Conclusion Throughout the discussion in this assignment, what has emerged is that the powerful States have been attempting, through th e United Nations Security Council to establish a bureaucratic arrangement of world’s governance in which the elite would be controlling world’s resources and power. The main idea behind this has been to ensure that the super powers maintain the status quo in terms of world’s politics, economy, culture and technology through the propagation of their ideologies and influence to the less powerful nations of the world. However, there has been a lot of challenges in establishing the new world order, which have to some extend compromised the economic, political, cultural and technological security of the rich nations. The discussion may be summed up as a competition between the bureaucrats and the common person, whom, through the assistance of grassroots movements and institutions has been empowered to rise up and challenge the exploitations and discriminations which comes with the establishment of a new world order. The United Nations Security Council has also been h indered by the presence of many non-governmental organizations, which work in partnership with governments of the developing world to empower the citizens with education, which is a very important tool in fighting the rich nation’s imperialism. Education has enabled many countries in the developing world to embark on research, especially on agriculture and technology, which has enabled them to become self-reliant in terms of food and technological advancement. This has denied the rich nations, through the UN Security Council an opportunity to propagate the idea of world order, especially through giving aid to these countries, with some strings attached. Reference List Abele, R.P.(2005). â€Å"A Users Guide to the USA Patriot Act and Beyond†. Oxford OX2 6DP: University Press of America. Balogun, M.J. (2011). Hegemony and Sovereign Equality: The Interest Contiguity Theory in International Relations. Oxford OX4 2DQ: Springer. Barlow, A.L. (2003). Between Fear and Hope: Gl obalization and Race in the United States. Lanham, MD: Rowman Littlefield. Chorafas, D.N. (1988). Electronic Funds Transfer. Wellington Square: Butterworths. Milanović, B.(2010). The Haves and the Have-Nots: A Brief and Idiosyncratic History of Global Inequality. Oxford OX2 6DP: Basic Books. Slaughter, A.M. (2005). A New World Order. Woodstock OX20 1TW: Princeton University Press. Stauffer, V., Williamson, B.J. (2005). New England and the Bavarian Illuminati. Oxford OX1 3BN: The Invisible College Press, LLC.

Power Tool Market Analysis Essay Example | Topics and Well Written Essays - 500 words

Power Tool Market Analysis - Essay Example Finally, the difference in the estimates is not material. The projected values represent a decline of approximately 11.5% over the last year's figure of 1.8 million units by U.S. Census Bureau. The values for the last 5 years show a continuous declining trend. The following table summarizes the historic actual values. From the above statistics, it can be concluded that the demand for power tools in this sector may not increase in 2007 as the economic activity is declining. The demand may infact decrease since lesser number of houses will be developed. The expenditure for residential construction is expected to be at $504 billion as per Realtor, and $434 billion as per Haughey, in 2007. This shows a declining trend as the last year's (2006) figures show that the expenditure was $581 billion and $608 billion for 2005 (Realtor, 2007). The actual historic data is shown in the table below (U.S. Census Bureau: 930 - Value of Private Construction Put in Place: 1995 to 2005, 2007). This declining trend indicates that this sector will have less demand of power tools in 2007 than it was in prior years. This is because the expenditure for construction will decrease and power tools industry provides the tools that are used for construction. Hence, demand will be negatively affected for this market. The expend

Business Writing Class Members Respond to Postings Assignment

Business Writing Class Members Respond to Postings - Assignment Example Backing up any claims made using facts and statistics or visuals also help in assertive writing, therefore giving a reader confidence as to the accuracy of the information. Writing involves assertiveness rather than aggressiveness which is rude or passiveness which comes out as inaccurate/doubtful. I think that this is a good idea. An on-site daycare would also give assurance to the employee that their child is in safe hands since they will be close to them throughout the day. Offering learning opportunities and free health checkups is also an extra benefit to the employees. The daycare will eventually improve on the company’s productivity since employees will focus on their daily work knowing that their children are well taken care of. However, I feel as though a proper organizational review must be conducted before the commencement of this research. This is in order to know the demographics of the employees working there. For example, their age, marital status, number of kids and age of kids. By so doing the researcher is able to ascertain whether most employees are married, have kids and whether the kids are below 5 years old. Such a research may not be feasible in an organization where most employees are single, do not have kids or if they have children they are above 5 years old. A daycare may not be of help in such an organization and it may end up being a waste of resources. I absolutely concur with you, showing credibility is significant in a research. It is important that your work is supported by credible examples, illustration, visuals or even expert opinions and all these be properly cited as a reference.

Determined and Free

Determined and Free Will Essay At this point in my life I believe there is a balance in how many of our choices are determined and how many are free. The things that are determined for us are factors like what we are born into such as our ethnicity and social status. Also, if your parents are religious, you are raised under the influence of that religion. Most children embrace that faith as their own. These are life factors that you can change eventually, but usually due to societal influences you stay with these predetermined decisions. Certain determined things won’t ever be able to be altered. The color of your skin, and how you are treated because of it, is determined by where we are placed in life. Whether we are born with a medical condition or disorder is something we have no control over. Also, whether we have access to higher education or opportunity to move social classes. Many circumstances we don’t have power over are situational. The free will choices in our lives are day-to-day decisions that we make. However, these choices can have a major impact in our lives. I think there are many influences that can affect your free will, but the final decision lies in your own hands. You decide what social and personal influences infiltrate your decision, and in that is power. Things like your faith and morals shape who you are, so to make a decision with absolutely no influence is not necessarily of your own â€Å"free will†. Free will is having a say in your own decisions, it doesn’t matter what influences you unless you feel it limits you. I also believe that people differ in the amount of free will they have. The predetermined factors are generally the same for everyone, but the free choices are different. This is because people choose to let certain factors limit them, and others do not. If someone cares whether others judge him or her, they are less likely to decide to do something they really want if it is odd or embarrassing. Same method works if someone cares if their parents approve or not of their choices. These are limitations to your free will that you choose to adhere to.

A Comparison of Shakespeares Sonnet 18 and Duffys Valentine Essay

A Comparison of Shakespeare's Sonnet 18 and Duffy's Valentine Shakespear's attitude towards his lover is she is superior to the summer and very beautiful " Shall I compare thee to a summer's day?" This show Shakespeare is thinking about comparing her to the summer but then he gives examples of how she is better than the summer. He says she is lovelier than the summer " Thou art more lovely and more temperate." He then goes on to say "Rough winds do shake the darling buds of May" this means that she is more like a darling bud of May than a rough wind that come in the summer. He also explains, using a metaphor that the summer doesn't stay forever, but she will be beautiful forever " And summer's lease hath all too short a date." Then he says that sometimes the sun is too hot and is hidden by clouds but her beauty is never hidden and she is perfect. "Sometimes too hot the eye of heaven shines. And often is his gold complexion dimm'd" He then uses a double metaphor to explain that every living this is doomed to die and that nature cannot stop itself from dying ...

Physics Dot Points Prelim

Physics syllabus dot point summary Nathan Kulmar 8. 2. 1. 1 describe the energy transformations required in one of the following: – mobile telephone – fax/modem – radio and television Energy is stored as chemical energy in the phone’s battery. Chemical energy is transformed into electrical energy to operate the phone.The microphone converts sound energy in to electrical energy. Antanna converts electrical to electromagnetic energy to send a siginal. The receiver speaker converts electric energy in to sound energy. 8. 2. 1. 2 describe waves as a transfer of energy disturbance that may occur in one, two or three dimensions, depending on the nature of the wave and the medium The energy from waves may spread out as a disturbance in Dimension- Energy travels in a straight line from the source 2 Dimensions- Energy spreads out in a plane or surface 3 Dimensions- Energy spreads out in to space surrounding the source in all directions 8.2. 1. 3 identify that mechan ical waves require a medium for propagation while electromagnetic waves do not Mechanical waves: require a medium, solid, liquid or gas to transfer energy. Electromagnetic waves: which don’t require a medium for transfer of energy. 8. 2. 1. define and apply the following terms to the wave model: medium, displacement, amplitude, period, compression, rarefaction, crest, trough, transverse waves, longitudinal waves, frequency, wavelength, velocity Medium: is what isn’t need for the electromagnetic spectrum to travel. Displacement: the distance from the point of equilibrium to the wave Amplitude: the distance to the point of maximum displacement Period: time taken o complete a single wave length Compression: an area where partials are pushed togetherRarefaction: point where a partial reaches it’s maximum displacement vertically down Crest: the point where a partial reaches it’s maximum displacement vertically up Trough: the point where a partial reaches itâ⠂¬â„¢s maximum displacement vertically down Transverse waves: the direction of travel is at right angles to the oscillation (figure 2) Longitudinal waves: the direction of travel is parallel to the oscillation (figure 1) Frequency: the number of oscillations that pass a point in a second.V. remoteMissilesNight visibility gogglesSoft tissue treatment| Microwaves| Antenna| MobilesSending info. Cooking| Radio waves| Antenna| CommunicationAstronomy| 8. 2. 3. 4 explain that the relationship between the intensity of electromagnetic radiation and distance from a source is an example of the inverse square law I? 1d2 The intensity of the electromagnetic radiation is proportional to 1 divided by the distance squared. As the waves travel further from the point of origin they spread out and become less intense. I=k/d2 I=intensity k=constant d= distance 8. 2. 3. outline how the modulation of amplitude or frequency of visible light, microwaves and/or radio waves can be used to transmit informatio n Information is converted into a wave and then placed on a carrier wave. It uses the properties of superposition to place the wave on to the carrier wave. Digital is made up of a series of one’s and zero’s. Digital encoding is made in to binary and are transmitted via light, microwaves, television waves and waves from the electromagnetic spectrum. There are two types of analogue transition one is AM. AM stands for Amplitude Modulation.This works by a using a high frequency carrier wave which has the modulation signal placed on it. Frequency will remain the same but amplitude will change. The other Form is FM. This stands for Frequency Modulation. A wave is frequency is chosen as the carrier wave and the modulation signal is placed on the carrier wave. Amplitude stays the same. 8. 2. 3. 6 discuss problems produced by the limited range of the electromagnetic spectrum available for communication purposes All EMR (electromagnetic radiation) will suffer attenuation (reduct ion in intensity) as they pass through the atmosphere or any other material.As the earth is bombarded with UV radiation from the sun the ionosphere becomes charged. This can cause problems such as ghosting which is a double image on your T. V. screen. Also large portions of EMR are unable to be used because they are too dangerous such as Gamma-rays and X-rays. Ultraviolet and visible are too difficult to produce and encounter too much interference. Near infrared and infrared also have difficult because of impurities in optical fibbers will absorbed the light. Microwaves and T. V. waves require line of sight to be practical. . 2. 4. 1 describe and apply the law of reflection and explain the effect of reflection from a plane surface on waves Electromagnetic waves may be reflected from a plane surface and they must obey the Law of Reflection: Angle of incidence equals the angle of reflection Incident ray, reflected ray and normal must all be in the same plane. 8. 2. 4. 2 describe ways in which applications of reflection of light, radio waves and microwaves have assisted in information transfer Light is used in optical fibbers to transmit data.The light is reflected off the inside of the glass tube and can carry multiple messages at the same time in a single fibber. Radio waves are reflected off the ionosphere to that they can travel a longer distance. Microwaves send transitions to satellites where they are reflected back through the atmosphere to earth. 8. 2. 4. 3 describe one application of reflection Plane surfaces Mirrors. They allow people to look at their bodies without distortion. Concave surfaces Satellite dishes. They focus incoming rays to a single point called the focus and energised the signal at this point. Convex surface Rear vision mirrors.They allow a large field of view in a small area but will give the viewer a false scene of distance Radio waves being reflected by the ionosphere Radio waves are reflected off the ionosphere to provide a greater distance to which a listener can be from the source of the broadcast. 8. 2. 4. 4 explain that refraction is related to the velocities of a wave in different media and outline how this may result in the bending of a wavefront Refraction is the phenomenon where waves appear to bend as the waves pass from one medium to another. If wavefronts strike a boundary at any other angle other than 90 ° than a change of speed will occur.If a wave goes from one medium to another and the speed is lower than it will bend towards the normal. If it goes into a medium where the speed is faster than it will bend away from the normal. The waves bend because the incident ray first strikes the medium it slows down and the rest of the ray continues at the same speed until it makes contact with the medium. It is the wavelength that changes not the frequency. 8. 2. 4. 5 define refractive index in terms of changes in the velocity of a wave in passing from one medium to another The refractive index is the ra tio of the two wave velocities during the efraction. The refractive index is a measure of how much the light bends. 8. 2. 4. 6 define Snell’s Law: V1V2=sin isin r V1 and V2 are the speeds of the waves in wave in the different mediums. Sin i is the angle of incidence and sin r is the angle of reflection. It is the relationship between speed, wavelength and angles of incidence refraction was determined experimentally by Willebrorod Snell and is known as Snell’s law. 8. 2. 4. 7 identify the conditions necessary for total internal reflection with reference to the critical angle If the critical angle is reached than the angle or reflection is 90 °.When the critical angle is exceeded than the light can’t escape and total internal refraction occurs. The light must be travelling from a medium with a higher refractive index to one with a lower refractive index. 8. 2. 4. 8 outline how total internal reflection is used in optical fibres Optical fibres are one application of total internal refraction. They are made of high purity glass, the central region is called the core and the outer region called the cladding. The cladding confines the light to the core and thus must have a lower refractive index than the core.Once information is digitally encoded, at the transmitting end, the signal is converted from electrical energy to light energy and then transmitted along the optical fibre. The information is sent as a series of coded pulses of light. The pulse is either on or off. At the receiving end it is decoded. 8. 2. 5. 1 identify types of communication data that are stored or transmitted in digital form CD ROMs (Compact Disk Read-Only Memory) these discs store data in digitised form as tiny bits. They are read using a low power laser beam. They cannot be edited and are read only.They are fairly slow to read and can only store 8000Mbytes DVD (Digital Versatile Discs) these disks can hole 5 billion bytes of data, thus making possible the storage of m emory consuming movie length video and sound. GPS (Global Positioning Systems) this worldwide system uses a fleet of 24 satellites that transmit signals constantly. A GPS system, few hundred dollars, can interact with the satellite to pinpoint your latitude, longitude and altitude with in 50m. 8. 3. 1. 1 discuss how the main sources of domestic energy have changed over time.The sources of domestic energy have changed rapidly over time: * 50,000 BC: control of fire: cooking and heating * 10,000 BC: domestication of animals: animal power for transport and ploughing. * 3,000 BC: wind and water power: sailing boats and windmills * 1750 AD: burning of coal begins to replace wood. Steam engines, trains, steam, ships. * 1780-1800: scientific investigations of the properties of electricity. Conflicting theories, scientific curiosity small amounts of energy in batteries. * 1830’s: discover how to generate electricity using a â€Å"dynamo† (generator).Still used in scientific la bs. * 1880-1910: a flood of inventions such as the light bulb, telephone, gramophone and radio were create with electricity. * 1950- : all industrialized nations had become totally converted to electricity for domestic power. 8. 3. 1. 2 assess some of the impacts of changes in, and increased access to, sources of energy for a community Some impacts of charges in sources of energy are: * The use of coal has had a particularly large impact on our society. * Coal burns hot fires to make steel and other metals. Steel major factor that lead to the industrial revolution. * Coal lead to the development of the steam engine. * Pollution and global warming was created. 8. 3. 1. 3 discuss some of the ways in which electricity can be provided in remote locations Use small generators that rotate a coil by a petrol or oil motor. Solar cells and wind generators are also used to convert sunlight and wind into electricity. 8. 3. 2. 1 describe the behaviour of electrostatic charges and the properties of the fields associated with them * Two types of charges positive and negative Charges go away from positive, charges go towards negative * An electrostatic charge is a charge due to an excess or deficiency of electrons. * A body with equal number of protons and electrons will be neutral. * Body has an excess of electron is negatively charged. 8. 3. 2. 2 define the unit of electric charge as the coulomb Electric charge is measured in coulombs the coulomb (c) is the SI unit of electric charge. 1 coulomb = 1c = 6. 25 x10^18 charge = 1. 6 x10^19 charge 8. 3. 2. 3 define the electric field as a field of force with a field strength equal to the force per unit charge at that point: E=FqE = magnitude of electric field (NC-1) Newton per coulomb q = charge (C) coulombs F = force (N) Newton 8. 3. 2. 4 define electric current as the rate at which charge flows (coulombs/ second or amperes) under the influence of an electric field Current is the rate at which charge flows (Csec. or Amperes) un der the influence of an electric field. I= QT I = current Q= charge (coulombs) T= time (sec) 8. 3. 2. 5 identify that current can be either direct with the net flow of charge carriers moving in one direction or alternating with the charge carriers moving backwards and forwards periodically DC = direct currentCharge moves in one direction Direct positive to negative movement AC = alternating current Charge moves back and forth periodically. Directions changes 50 times per second. 8. 3. 2. 6 describe electric potential difference (voltage) between two points as the change in potential energy per unit charge moving from one point to the other (joules/coulomb or volts) Electric potential difference (Voltage) between two points is the change in potential energy per unit charge moving from one point to another (joules/coulomb or Volts). . 3. 2. 7 discuss how potential difference changes between different points around a DC circuit Potential difference can vary at different points around a circuit for example there will be different voltage drops across various resistors, light globes and rheostats which would be different to the voltage rise across the power pack. 8. 3. 2. 8 identify the difference between conductors and insulators Insulators will not allow electricity to flow through them because they have a very high resistance.Conductors have a very low resistance and therefore will allow current to flow through them. 8. 3. 2. 9 define resistance as the ratio of voltage to current for a particular conductor: V=IR V= Voltage I= Current in amps R= Resistance in ohms 8. 3. 2. 10 describe qualitatively how each of the following affects the movement of electricity through a conductor: Length: Resistance is proportional to length; the longer a conductor the greater the resistance Cross sectional area: larger the cross-section the lower the resistance.Temperature: temperature increases ions vibrate increasing resistance. Material: material of a conductor influences resi stance; copper is commonly used for household wiring, gold or silver used when minimal resistance required. 8. 3. 3. 1 identify the difference between series and parallel circuits Series: * There is only one current pathway. * Current is the same throughout the whole circuit * If a series circuit is broken at any point then the electricity cannot flow through it. * Current remains constant and voltage varies (VT=V1+V2+V3).Parallel: * There is more then one current pathway. * All components have the same potential difference across them * In parallel, voltage remains constant and current varies (IT=I1+I2+I3). 8. 3. 3. 2 compare parallel and series circuits in terms of voltage across components and current through them Parallel| Series| VT= V1 = V2 = V3| VT= V1 + V2 + V3| IT=I1 + I2 + I3| IT=I1 = I2 = I3| 8. 3. 3. 3 identify uses of ammeters and voltmeters Ammeters measure the flow of electrons through a point in the circuit.Voltmeters measure the potential difference between two poin ts. 8. 3. 3. 4 explain why ammeters and voltmeters are connected differently in a circuit Ammeter: cannot change the current being measured, must have minimum resistance, current must flow through the ammeter, MUST BE PLACED IN SERIES Voltmeter: measure the penitential difference (voltage) between two points in a circuit, PLACED IN PARALLEL CURCUITS, important that voltmeter has high resistance so that there is not affect on the circuit. 8. 3. 3. explain why there are different circuits for lighting, heating and other appliances in a house In a house there are separate circuits for lighting, heating and other appliances so that appliances that require large amounts of current can still function without over-loading the circuit. If everything was on one circuit there would be too much current used and the wires would become hot and potentially cause a fire. 8. 3. 4. 1 explain that power is the rate at which energy is transformed from one form to another Power is defined as the rate a t which energy is transformed from one form to another. watt=1 W=1J/s 1kW=1000watts P=ET Power ((Joules = watts (W)) = Energy (J) / time (s) 8. 3. 4. 2 identify the relationship between power, potential difference and current Power is the number of joules per second (watts), for every current (I in Amps), Voltage (v in volts) are dissipated. P=VI Power (Watts) = Voltage (V) x Current (A) 8. 3. 4. 3 identify that the total amount of energy used depends on the length of time the current is flowing and can be calculated using: Energy=VIt Electrical energy (joules) = Voltage (volts) x Current (amps) x Time (sec) P=VIPower (Watts) = Voltage (V) x Current (A) P=ET Power ((Joules = watts (W)) = Energy (J) / time (s) 8. 3. 4. 4 explain why the kilowatt-hour is used to measure electrical energy consumption rather than the joule 1kW. h is the energy used by a 1 kW appliance operating for 1 hour. Measuring in joule is a big inconvenient because 1 joule is a very tiny amount of energy. 8. 3. 5. 1 describe the behaviour of the magnetic poles of bar magnets when they are brought close together Magnets have 2 different poles north and south. They can either be attract or repel each other.Opposite poles attract, same poles repel. 8. 3. 5. 2 define the direction of the magnetic field at a point as the direction of force on a very small north magnetic pole when placed at that point The direction of a magnetic field is the direction of force on a very small magnetic north pole placed in the field. The currents from the north pole more towards to the south pole. 8. 3. 5. 3 describe the magnetic field around pairs of magnetic poles Field lines come out of the North and into the south. Field lines never cross. The magnitude of the field is indicated by the density of the field lines. . 3. 5. 4 describe the production of a magnetic field by an electric current in a straight current-carrying conductor and describe how the right hand grip rule can determine the direction of current an d field lines The direction of the magnetic field is described by the right hand rule. Right hand grip rule: Grip wire with right hand, thumb pointing in direction of conventional current, fingers will curl around in the direction of the magnetic field. 8. 3. 5. 5 compare the nature and generation of magnetic fields by solenoids and a bar magnet * A solenoid is a coil of wire. When a current flows in the solenoid it produces a magnetic field around the coil which is similar to that of a bar magnet. * In a solenoid the field continues through the middle as parallel lines. * The direction of the magnetic field inside a solenoid is given by the right hand rule. 8. 3. 6. 1 discuss the dangers of an electric shock from both a 240 volt AC mains supply and various DC voltages, from appliances, on the muscles of the body * The neuromuscular system runs on the movement of electrical changes. An electric current through the body has the effect to disrupt its normal function. A typical respons e of your body’s muscles to an electric shock would be: * Muscles contract so you won’t be able to let go. * Muscles controlling the diaphragm cause it to clamp (can’t breathe) * Heart muscle goes into fibrillation (stops effective beating till heart stops altogether) * Death * Human bodies can withstand ten times as much DC current as AC, AC operates on frequency (50-60 Hz) which is the same frequency our heart operates making AC significantly more lethal than DC. 50-100 mA are the lethal limits for electric shock. 8. 3. 6. describe the functions of circuit breakers, fuses, earthing, double insulation and other safety devices in the home Circuit breakers: they use an electromagnet to mechanically break the circuit. Once the current exceeds the maximum value. Fuses: they prevent overloading of circuits. They are made of a metal with a low melting point. They melt when the current through the circuit exceeds the wiring. They are usually contained in high melting point materials to avoid fires. Earthing: they protect from shock. If an appliance has any metal exposes than it will have the outer cover earthed to protect shock.It works on the bases that there is less resistance through the wire rather than through a person. Double insulation: house hold wiring must be covered by an insulator. Usually made of plastic ((polyvinylchloride, (PVC)) many have double insulating in case the inner insulation melts when the metal gets to hot. 8. 4. 1. 1 identify that a typical journey involves speed changes In a typical car journey, a car may travel at different speeds, accelerate and decelerate, changes direction and stops therefore although there is an average speed for the entire journey, the vehicle does not travel at a constant speed. . 4. 1. 2 distinguish between scalar and vector quantities in equations Scalar quantities are those that specify size (magnitude), but not direction. Vector quantities are defined by both size (magnitude) and direction . Vectors| Scalar| Force| Mass| Velocity| Speed| Displacement| Distance| Acceleration| Work| Momentum| Energy| Magnetic Fields| Power| Electric Fields| Time| 8. 4. 1. 3 compare instantaneous and average speed with instantaneous and average velocity Average Speed = Distance/Total Time Instantaneous Speed is the speed of an object at a particular instant of time.Velocity (v) is the time rate of change of the displacement. It is a vector; it requires both size and direction. It is speed with a direction. Displacement (s) is distance in a given direction. Instantaneous velocity is the velocity at a particular instant, the speed and the direction. Average Velocity is displacement/time. 8. 4. 1. 4 define average velocity as: vav= ? r? t r = s = displacement. Average velocity= change in displacement/ change in time. 8. 4. 2. 1 describe the motion of one body relative to another Motion occurs when an object changes its position relative to other or some co-ordinate system (a frame of refere nce).If a change in direction occurs thorough vector qualities, must be dealt with as vectors. 8. 4. 2. 2 identify the usefulness of using vector diagrams to assist solving problems Vectors qualities have magnitude and direction. Adding Vectors Draw the first vector. Draw the second vector starting from the end of the first. The resultant vector is the line joining the beginning of the first vector to the end of the second. 6km 8km 10km a 6km 8km 10km a Subtracting Vectors V1 – V2 = Change in VChange V = V (f) – V (i) V1 -V2 V1 – V2 V1 -V2 V1 – V2 Change = Final – Initial Change V 8-(-10) = 18 -10m/s 8m/s -10m/s m/s 8. 4. 2. 3 explain the need for a net external force to act in order to change the velocity of an object Forces can internal or external to a system but only the external forces can affect the motion of the system. Net force = sum of all forces. Change in velocity the object must accelerate. An object will remain in constant motion (res t or 0 velocity) unless an unbalanced force acts on the object. To accelerate there must be an outside force acting (Newton’s 1st law). Newton’s first law states that: A body continues in its state of rest or uniform velocity unless acted upon by an unbalanced force. . 4. 2. 4 describe the actions that must be taken for a vehicle to change direction, speed up and slow down Acceleration is defined as the time rate of change of velocity. Acceleration refers to: Speeding Up: this can be done by using the accelerator Slowing Down: this can be done by using the cars brakes Changing Direction: Using the steering wheel 8. 4. 2. 5 describe the typical effects of external forces on bodies including: Friction between surfaces Air resistance There are a number of external forces working on a car and these include: Friction with the Road Air Resistance The weight of the carFriction is a force that we encounter everyday in everything we do. Friction is a force that always opposes m otion. Friction arises when two different materials are in contact with each other. The tires make contact with the road surface and as a result there is friction. This means that the vehicle has traction and does not simply slide. Air Resistance is a form of Friction. As a vehicle moves through the air the two materials, the vehicles body and the air, move past each other. Air resistance limits the speed of the vehicle but it can be minimized by designing a vehicle so that it is aerodynamically shaped. . 4. 2. 6 define average acceleration as: vav= ? r? t therefore vav=v-ut Acceleration is a change in velocity over a certain time period. It can be positive or negative. v= final velocity, u= initial velocity, t= time taken 8. 4. 2. 7 define the terms ‘mass’ and ‘weight’ with reference to the effects of gravity Mass: Is the measure of the amount of matter in an object Measure of inertia (resistance to acceleration) Independent or the effects of gravity Measu red in grams. Weight Is the force of gravity on an object. On earth weight is the mass x 9. 8 Dependent on the amount of massMeasure of the gravity and force on an object Measured in Newton’s. 8. 4. 2. 8 outline the forces involved in causing a change in the velocity of a vehicle when: Coasting with no pressure on the accelerator Friction with the Road Air Resistance Force Pushing car along Pressing on the accelerator The driver is supplying more fuel to the engine. This allows the engine to apply a greater force on the wheels and hence make the car speed up. Velocity and acceleration acting in the same direction. Pressing on the brakes Increasing the friction between the brake pads and the metal discs making it harder for the wheels to turn.Velocity and Acceleration acting in different directions. Passing over an icy patch on the road There is less friction and the wheels can’t get as much grip so they may slide. The car will move at a constant velocity until acted up on by an external force. Climbing and descending hills Friction Air Resistance The cars weight causes it to slow down when going up the hill and speed up when going down the hill Following a curve in the road Centripetal force is causing the car to accelerate as the velocity is changing owing to the change in direction. 8. 4. 2. interpret Newton’s Second Law of Motion and relate it to the equation: F=ma F= Force in Newtons m= mass a= acceleration 8. 4. 2. 10 identify the net force in a wide variety of situations involving modes of transport and explain the consequences of the application of that net force in terms of Newton’s Second Law of Motion The acceleration of an object is proportional to the unbalanced force acting on it and is inversely proportional to the mass. The consequences of net external force acting on a model of transport are acceleration, deceleration and a change of direction in motion.Centripetal force (circular motion) The force causing the turning is always towards the centre of the circle. Force (centripetal) = mv^2/ R R=radius, V= instantaneous velocity, M= mass 8. 4. 3. 1 identify that a moving object possesses kinetic energy and that work done on that object can increase that energy Kinetic Energy is the energy an object possesses because it is moving. Kinetic energy is dependent on the mass and the square of the velocity of the body as indicated by: KE=12mv2 E= kinetic energy (joules) M=mass of the object (kg) V=velocity (m/s)Work (W) is done when a force (F) is moved through a distance (s). Work is the product of a force and the distance moved in the direction of that force. W=Fs. Work transfers energy through the motion of a force. When work is done, energy is required. W = Change in Kinetic energy 8. 4. 3. 2 describe the energy transformations that occur in collisions In collisions objects exert forces on each other. Collisions can be either: Elastic Non-Elastic Elastic Collisions If in a collision, kinetic energy is conserved, the collision is said to be elastic.An example would be when Gas molecules collide with each other and with the walls of their container as kinetic energy is not decreased. Inelastic Collisions In inelastic collisions, kinetic energy is not conserved. Some of the Kinetic energy is transformed into other forms of energy such as heat and sound. If the colliding parts stick together, the collision is inelastic 8. 4. 3. 3 define the law of conservation of energy In all types of interactions, both elastic and inelastic, total energy is conserved. Energy cannot be destroyed only can be changed from one form to another. . 4. 4. 1 define momentum as: p=mv Momentum= mass (kg) x velocity (m/s) Unit of momentum= kilogram-meter/sec To stop a moving object, forces must be applied and the forces relate to two factors, the mass of the object and the velocity of the object. The time rate of change of momentum is proportional to the resultant force and acts in the direction of the force. Always conserved Vector quantity 8. 4. 4. 2 define impulse as the product of force and time Impulse = F (force) x t (time) Impulse = change in momentum Impulse = Ft = mv – mu mv = final momentum u = initial momentum The unit of Impulse is N. s which is the same as the Unit of momentum= kilogram-meter/sec (kg. m/sec) 8. 4. 4. 3 explain why momentum is conserved in collisions in terms of Newton’s Third Law of motion Force (action) = Force (reaction) Conservation of Momentum The total momentum of a system is always the same unless the system on by some external force. P (before) = P (after) m1u1+m2u2= m1v1+m2v2 This equation shows that: the vector sum of the momentum of the objects before collision equals the vector sum of the momentum after collision.Momentum is conserved only in isolated systems (those free from external forces). The Law of the Conservation of Momentum can be stated as: In interactions between objects, momentum is conserved in an isolated system. 8. 4. 5. 1 define the inertia of a vehicle as its tendency to remain in uniform motion or at rest Newton’s 1st law: Inertia: â€Å"Tendency of any object to resist any change in motion. † E. g. when a car stops suddenly, the objects and people in the car remain in the current motion unless acted upon by an external force such as a seatbelt. 8. 4. 5. discuss reasons why Newton’s First Law of Motion is not apparent in many real world situations Common experience is not apparent in Real World Situations as the driver of a car still needs to depress the accelerator to move at a constant rate because of friction between the car and the road. 8. 4. 5. 3 assess the reasons for the introduction of low speed zones in built-up areas and the addition of air bags and crumple zones to vehicles with respect to the concepts of impulse and momentum Introduced low speed zones into built areas to reduce the speed of drivers as the faster you are moving the more damage you do in a coll ision.Crumple Zones were introduced so that the front and rear end of the car should crumple in a collision which increases the time it takes for the car to come to rest so the forces are lessened. Air Bags were introduced which provide a cushion and takes the impact out of a collision. 8. 4. 5. 4 evaluate the effectiveness of some safety features of motor vehicles Seat Belts They are effective in limiting the effect of inertia when a vehicle breaks suddenly. It absorbs a lot of the force of a collision. Airbags Air Bags were introduced which provide a cushion and takes the impact out of a collision.Crumple Zones Crumple Zones were introduced so that the front and rear end of the car should crumple in a collision which increases the time it takes for the car to come to rest so the forces are lessened. 8. 5. 1. 1 outline the historical development of models of the Universe from the time of Aristotle to the time of Newton Plato| planets move in spherical orbits around the earth (geoce ntric) | Eudoxus| maintained Plato’s concepts of spherical motions, complex arrangements of circular motions| Aristotle| developed Eudoxus model to 53 spheres. |Aristarchus| The sun is in the centre (heliocentric) with everything orbiting around it and epicycle moments to explain planetary movements; Earth must rotate on its axis, so it appears that everything moves around us. | Ptolemy| believed in geocentric universe, stars existed on a sphere which rotated every 24 hours, earth is a sphere and at rest, motion of sun and plants moved in perfect circles. | Copernicus| heliocentric universe, sun was the centre and planets orbited the sun in fixed circular motions, earth traveled around the sun in 1 year and spins on its axis every 24 hours. Galileo| first to use a telescope, supported the heliocentric idea of Copernicus, worked on gravitational theory disproved Aristotle concepts of the motion. | Sir Isaac Newton| from work on motion realized that a forcer must be acting on a n object such as the moon, law of universal gravitation, this explain where things stayed in orbit, since the time of Newton the heliocentric model was accepted. | 8. 5. 2. 1 outline the discovery of the expansion of the Universe by Hubble, following its earlier prediction by Friedmann Alexander Friedman predicted that the universe was expanding.The predictions rose from calculations based on Einstein’s, general theory of relativity. Edwin Hubble designed a new and a bigger telescope that leads to the discovery of the red shift proving that the universe is expanding. A red shift corresponds to a shift to the lower frequency (longer wavelength). This indicates that the light source, the galaxy is moving away from us. All galaxies show this effect indicating that the universe is expanding. 8. 5. 2. 2 describe the transformation of radiation into matter which followed the ‘Big Bang’ After the temperature had dropped enough.The energy began to be converted in to matt er. Hydrogen atoms formed from protons and electrons. 8. 5. 2. 3 identify that Einstein described the equivalence of energy and mass E=mc2 E= energy (Joules) m= mass (kg) c= speed of light (3 x 108 ms-1) 8. 5. 2. 4 outline how the accretion of galaxies and stars occurred through: Expansion and cooling of the Universe The cooling of the universe allowed the formation of matter. This began to overwhelm the radiation Subsequent loss of particle kinetic energyAs the temperature fell this resulted in a loss of kinetic energy (as temperature is the measure of average kinetic energy of the particles) Gravitational attraction between particles Loss in Kinetic energy meant that the increased gravitational force between particles took effect Lumpiness of the gas cloud that then allows gravitational collapse The greater density of areas of the gas clouds allowed gravity to begin 8. 5. 3. 1 define the relationship between the temperature of a body and the dominant wavelength of the radiation em itted from that body The hotter the star the shorter the wave length.Hot star: short wave length, more energy. Cold star: long wave length, less energy 8. 5. 3. 2 identify that the surface temperature of a star is related to its colour Red | Long wavelength| Orange| | Yellow | | White blue- white| Short wavelength| The hotter the star gets the more it will shift towards the blue end of the spectrum and thus the shorter the wavelength. 8. 5. 3. 3 describe a Hertzsprung-Russell diagram as the graph of a star’s luminosity against its colour or surface temperature In the Hertzsprung-Russell diagram a stars surface temperature and luminosity (brightness) are plotted against each other.This is because there is a relationship between the two. 8. 5. 3. 4 identify energy sources characteristic of each star group, including Main Sequence, red giants, and white dwarfs Star group| Fuel| Characteristics| Main sequence| H then He| They are from the top left of the Hertzsprung-Russell diagr am to the bottom right. This shows a trend of hot and bright to cold and dull| Red giants| H then He| In the upper right corner of the Hertzsprung-Russell diagram and are bright but cold| White dwarfs| C and O ions| Bottom left of the Hertzsprung-Russell diagram. They are very hot but dim and small. 8. 5. 4. 1 identify that energy may be released from the nuclei of atoms Light atoms like H will fuse together at extreme temperatures to for stable atoms. This produces energy. Uranium on the other hand has very unstable nuclei and will break down by emitting energy or partials randomly. That may be in the form of ? , ? or gamma rays. 8. 5. 4. 2 describe the nature of emissions from the nuclei of atoms as radiation of alpha ? and beta ? particles and gamma ? rays in terms of: ionising power penetrating power effect of magnetic field effect of electric fieldRadiation| Ionizing power| Penetrating Power| Effect of Magnetic Field| Effect of Electric Field| Alpha Particle| Very high Strong| Low a few cm in the air| Affected according to right hand palm rule| Limited – very small| Beta Particle| Less than AlphaWeak| Higher than Alpha thin sheets of lead| Large| Large| Gamma Ray| Less than BetaVery Weak| Very High Several cm of lead| Zero| Zero| 8. 5. 4. 3 identify the nature of emissions reaching the Earth from the Sun Solar wind consists of a stream of ionised particles, mostly protons and electrons that flow from the sun in all directions at speeds of about 400 km. -1. The source of the wind is the sun’s hot corona – the outer atmosphere of the sun extending a distance of a few solar radii into space. Most of the corona consists of vast arches of hot gas – solar flares – that are millions of kilometres in length and are caused by the sun’s magnetic field. The Solar wind comes from regions called coronal holes, regions of cooler, less dense gas. As the sun rotates there is a periodic variation in Solar wind activity every 27 da ys. The Solar wind is responsible for pushing the tail of comets away from the sun. 8. 5. 4. 4 describe the particulate nature of solar windSunspot cycle is a pattern of increasing and decreasing sunspots. Sun spots are a dark spot on the sun with lower temperatures and intense magnetic activity. Cycle is between 7-13 years. Two types of emission reaching Earth from the sun: electromagnetic radiation and solar winds. Earth’s atmosphere and magnetic field shelters as from theses emissions. The sunspots themselves last for several days although larger ones may last up to a few weeks. The number of particles and their velocity increases following sunspot activity and solar flares meaning that the solar wind is greater in the time of maximum sunspots. . 5. 4. 5 describe sunspots as representing regions of strong magnetic activity and lower temperature Sunspots are relatively cool areas (~4500K), with magnetic field strengths some thousands of times stronger than the Earth’ s magnetic field, that appear as dark imperfections in the photosphere. They result from the penetration of magnetic field lines through the photosphere and are ~8000km across. Except for the smaller ones, all sunspots have a dark inner region – the umbra – where the magnetic field is strongest surrounded by a less dark region – the penumbra – where the magnetic field is weakest.

Aetiology, pathogenesis, diagnosis and treatment Cystic fibrosis: role of P. aeruginosa infection in cystic fibrosis patients

Introduction Cystic Fibrosis (CF) is a genetic disorder of salt and water regulation in the cell. The disease is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene (Cohen and Prince, 2012). The molecular basis of CF depends on its transmembrane conductance regulator (CFTR) protein, which functions as a channel and regulates the movement of ions and water across the epithelial barrier. The barrier opens in response to increased levels of intracellular cyclic adenosine monophosphate (cAMP). The gene in normal condition is responsible for salt (chloride) and water balance in the body. However, if mutated, is not able to excrete out enough salt of the cell; thus resulting, the build of salt within the cell forming sticky mucus. If accumulated in the lungs, this sticky mucus may clinically affect the epithelial innate function of the lungs and may result in ineffective airway inflammation that fails to eradicate pulmonary pathogens (Cohen and Prince, 2012). The working mechanism of CFTR protein under normal condition is shown in figure 1. Studies have shown that increase in sodium (Na) re-absorption on the epithelial cells may indicate an event in cystic fibrosis lung disease (Cohen and Prince, 2012). These mutations on the (CFTR) protein have impacts on its production and transfer to the epical membrane of the epithelial cells, thereby influencing the conductance of chloride and bicarbonate ions across the channels resulting in the CFTR ionic imbalance of on the epithelial cells of different organs. This leads to the formation of excessive mucus in the cells, which provides an ideal condition for bacteria growth and multiplication. Interestingly, even uncommon lung bacteria such as pseudomonas have been found to inhabit in the lungs exploiting the ideal condition (Clunes and Boucher, 2007). Abnormality in the CFTR pathway results in the increase of glycolipids on the surface of CF airway epithelial cells. These glycolipids serve as receptors to increase the binding activities of bacteria, thereby facilitating the early infection process, which is a hallmark of the disease. Moreover, defect in CFTR gene is also associated with decreased nitric oxide concentration in the cell. Nitric oxide possesses antibacterial properties; thus, decrease in its concentration may predispose an individual to severe infections with faulty CFTR gene (Clunes and Boucher, 2007). In addition, the role of inflammation in CF pathogenesis seems equally important. Inflammatory response produced against the infectious pathogens in CF patients may have detrimental effects to the host cells. Inflammatory infiltrates including macrophages, neutrophils, cytokines and interleukins may induce tissue damaging responses, further deteriorating the lung function (Cymberknoh, et.al. 2013). Inhabitation of bacteria in cystic fibrosis lung As mentioned earlier, even uncommon bacterium including Pseudomonas aeruginosa can reside in the cystic fibrosis lung (Hauser, et.al. 2011). Pseudomonas aeruginosa is a gram negative, rod shaped, aerobic bacterium that prefers moist environment for growth. Commonly they are found in places such as sewage and in certain areas of the human body. Furthermore, they reside in lakes, moist vegetables, moist soil and streams. Studies have also suggested that that most human infections due to P. aeruginosa result due to contact with these natural reservoirs (Friman, et.al. 2013). Pseudomonas aeruginosa has been recognized as an important pathogen in CF. Soon after residence in the lungs, it becomes extremely difficult to eradicate them by antibiotics. The persistent presence of these bacteria in the lungs ultimately results failure of the immune system to provide a defense against them; this leads to respiratory failure resulting in death of the patient (Folkesson, et.al. 2012). Firstly, P.aeruginosa acquires the airway of the patient with cystic fibrosis, which occurs during the very early phase of the disease. Infection may ensue once this bacterium enters the CF host and colonizes the oropharynx, then to the lower respiratory tract by process of micro aspiration. Infection becomes intermittent at the initial stage as a result of acquisition of different strains. During the early stage of infection, the isolate looks like environmental strains, non-mucoid and susceptible to antibiotics. Eventually P. aeruginosa establishes itself and chronic infection ensues (Folkesson, et.al. 2012). In chronic stage of CF, P. aeruginosa produces a mucoid alginate by growing in bio-film of the end- bronchiolar space. It lacks lipopolysaccharide and becomes non-motile, resulting in the development of antibiotic resistance during. Despite the known mechanism and availability of antibiotics, P.aeruginosa is able to chronically infect the airway of patients with CF and is able to cause an unrelenting decline in pulmonary function and deterioration; but how these happen has been focus on intense research (Folkesson, et.al. 2012). Molecular pathogenesis of P.aeruginosa infection in CF The molecular basis of infection due to P. aeruginosa in CF is still not fully understood. However, it may be peculiar to a specific strain at the time of adaptation after acquisition. Studies have indicated that the persistence of the bacterium in the lungs might be due to its high level of propensity and the ability to adapt with environmental changes and stress (Hauser, et.al. 2011). aeruginosa possesses traits that enable them to colonize and persist in acute and chronic infection. These traits include; High resistance to antibiotics (Zhang, et.al. 2011) Effective cell-cell communication singalling for growth and multiplication (Friman, et.al. 2013). Ability to form biofilms, plethora and virulence products and metabolic versatility (Wagner and Iglewski, 2008). The biofilms are synthesized by the bacterium encased within a hydrated polymeric matrix and are clinically important; this is because, P. aeruginosa in this mode of growth utilizes it to cope with phagocytes by the neutrophils and macrophages, as well as to the killing by antibiotics. This allows them for persistent survival in chronically infected CF despite the continuous natural immune response and antibiotics effect (Zhang, et.al. 2011). The disease pathogenesis and severity is further triggered by inflammatory responses in the later stage of the disease. Mainly the pro-inflammatory enhancers become physiologically active in the absence of function CFTR gene. Although the exact inflammatory pathophysiology of CF still remains debatable, persistent infection, poor pathogen clearance, acidic environment and are considered some of the key triggers for initiating chronic inflammatory response in the lungs of the patient with CF (Pier, 2008). The mechanism is explained in figure 2. Synthesis of ceramide from sphingomyelin by acid sphingomyelinase (ASM) and degradation by acid ceramidase (AC) is optimal at an acidic pH, such as that of normal intracellular vesicles (pH 4.5). Lack of functional CFTR increases vesicle pH to 5.9, partially inhibiting ASM and highly inhibiting AC, resulting in ceramide accumulation in the vesicle and age-dependent pulmonary inflammation. Other properties of the cystic fibrosis–affected lung, including lack of the CFTR receptor needed for clearing Pseudomonas aeruginosa, enhanced mucin secretion, a dehydrated airway surface liquid, viscous mucus and DNA deposits released from ceramide-engorged apoptotic cells, also contribute to P. aeruginosa airway colonization. Eventually, this microbe establishes a chronic infection wherein bacterial cells reside in low-oxygen mucus plugs and become highly resistant to clearance or killing by host defenses (Pier, 2008) P.aeruginosa potentially synthesize factors such as proteolytic enzymes, which damage the host cells by altering the host iron-containing protein forming hydroxyl radicals that contribute to host tissue injury and inflammation; thereby decreasing the level of anti-inflammatory cytokines including IL-10, and at the same time, activating neutrophils in the airway lumen. Continuous recruitment of these neutrophils induces tissue damaging inflammatory response mainly affecting pulmonary tissue. Furthermore, neutrophils trigger the production of pro-inflammatory cytokine such as IL-8, which further contributes in the tissue damage process. In addition to pro-inflammatory cytokines, neutrophils also release the oxygen free radicals that induce apoptosis (programmed cell death) of the epithelial tissue in the lungs. Thus, to conclude, the role of neutrophils in airway inflammation in patients with CF seems crucial. Instead of providing innate immunity to the infected lung, it rather trigger s detrimental inflammatory response and promote the growth of P. aeruginosa though the production of different growth enhancing cytokines, leading to the destruction of the lung tissue (Sagel, et.al. 2009). The effectiveness of the immune response in CF is exploited, allowing the establishment of a relentless cycle, whereby persistent bacteria cause increased inflammation that itself leads to increased bacterial densities, which in turn results stronger inflammatory response (Sagel, et.al. 2009). The net result is progressive tissue damage and pathological consequences and sequelae of CF that include mucopurulent plugging of bronchioles, chronic bronchitis (inflammation of the bronchioles) and bronchial gland hyperplasia (increase in the cell size of bronchial gland cells). The airway later becomes dilated and results bronchiectatic due to loss of support cartilage (Pickett, 2013). Treatment options for cystic fibrosis The decision to treat patients who are infected with P.aeruginosa can be very challenging. Prolonged treatment with antibiotics can have toxic side effects, as well as increases the chance of microbial resistance in the patients. Also, prolonged treatment may cause long term harm. Data suggest that 80% of the patients with CF die indirectly or directly from pulmonary disease (Hurley, et.al. 2012). Clinically, there has been very little progress in the development of new antibiotics with novel mode of action. Recently, researchers exploited the adjuvant therapeutic agents that may be used alongside the conventional antibiotics. Source control measures, de-escalation of antibacterial should be followed up in patients with clinical response, especially with known antibacterial susceptibilities (Hurley, et.al. 2012). Considering the virulence of this pathogen, the progress of various strategies such as efflux pumps and lectins, the use of iron chelators, immunization, immunotherapy, and inhibition of quorum sensing are currently being tested clinically for the better management of the disease. It has also been suggested that the impacts of intervening virulence of P. aeruginosa should also be assessed (Hurley, et.al. 2012). Some novel therapies are also based upon the fact that CF is caused by the mutation of the gene encoding CFTR protein; targeting the defects produced in CFTR with invacaftor in one such approach. This novel treatment seems promising in patients with specific genotype of CF. Although the long term-outcome remains unknown, the development of CFTR targeted drug is an important milestone in CF (Petit, et.al. 2012). More recently, gene therapy has been extensively studied for the complete cure of the disease. However, the technique is not easy and has several limitations and hurdles. For instance, the research on this approach is very time consuming and often very expensive. However, focus of research has been on identifying the optimal vector for gene therapy (Picket, et.al. 2013). Thus, the management of CF has been a major challenge ever since the discovery of the disease. However, advancement in medical technologies and treatments has improved the prognosis of the disease. More sophisticated treatment including gene therapy (replacing faulty CFTR gene with a normal gene) has been the focus of intense research. P. aeruginosa resistance in CF Pseudomonas aeruginosa is one of the common infections in western society, because of its high level of resistance to antibiotics. The synergistic relationship between the outer membrane permeability and the efflux pumps is the most important factor influencing intrinsic antibiotic resistance in Gram-negative bacteria like P. aeruginosa (Liu, et. al. 1996). The high level of P. aeruginosa resistance is due to the acquired genes coding for amino glycoside-modifying enzymes or periplasmic beta-lactamases or mutations in fluoroquinolone targets (Liu, et.al. 1996). Low outer membrane permeability, which is caused by either less production of the OprD porin, or by expressing multidrug resistance efflux pumps contributes to high level of intrinsic antibiotics resistance (Liu, et.al. 1996). Numerous efflux pumps such as MexAB-OprM and MerXY-oprMb MexAB-OprM, MeXY-OprM, MexCD-OprJ, MexEF-OprN, MexJK, MexGHI-OpmD, MexVM, MexPQ-OpmE, MecMN and TriABC are encoded in the genome of Pseudomonas aeruginosa. These are of clinical importance because of their chemical ability to remove chemical-unrelated antibiotics. Among all, resistance-nodulation division (RND) super family contains the main efflux pumps of P. aeruginosa. This efflux pump has been discussed in greater details below. The energy source is derived from its proton motive force. Resistance Nodulation Division Efflux Pump Structure There are five families of multidrug resistance efflux pumps which include the ATP-binding cassette (ABC) super family, the major facilitator super family (MFS), the multidrug and toxic-compound extrusion (MATE) family, the small multidrug resistance (SMR) family and the resistance nodulation division (RND) family (Paddock, 2006). Efflux of antibiotics from the periplasm is a critical mechanism of antibiotic resistance utilized by Gram-negative cells. P. aeruginosa is capable of actively effluxing antibiotics from the periplasmic space using efflux pumps primarily from the RND family. The RND complex is tripartite in nature, composed of an outer membrane channel protein (OMP), inner membrane RND transporter, and a membrane fusion protein (MFP) (Kumar and Schweizer, 2005). The RND transporter provides the energy for the molecular transport and is often referred to as the RND pump protein (Misra and Bavro, 2009). The OMP interacts with the RND protein in the periplasm producing a chann el capable of transporting antibiotics into the extracellular space. The MFP is believed to stabilize the interactions between the RND transporter and the OMP (Misra and Bavro, 2009). All three of these components are essential for efflux function. The RND transporters are comprised of a homotrimer folded into a ?-helical transmembrane domain, with a large, soluble periplasmic domain. The top of the bacteria have semi-permeable membranes which may limit the passage of some types of antibiotics into the cell (Avrain, et.al. 2013). Multidrug resistance efflux pumps allow the bacterium to pump antimicrobials out of the cell. Porins maintain osmotic pressure by allowing the entrance/exit of hydrophilic small molecules but do not permit the passage of larger molecules. Enzymes can modify the antibiotic so that it is no longer recognized by the target, or modify them so that they are no longer functional. This is particularly prevalent with antibiotics that alter the ribosome or interfere with ribosome binding to inhibit protein synthesis. Inhibition of mRNA synthesis occurs by binding to DNA dependent RNA polymerase inhibiting initiation (Avrain, et.al. 2013). The mechanism of antibiotic resistance is shown in figure 3. Fig3: Different mechanisms of antimicrobial resistance in Gram-negative bacteria (adapted from Fluit, et.al. 2001). In the figure, A represents mRNA and B represents tRNA. When exposed to antibiotics, MexAB-OprM and MexXY-OprM remain inducible but the rest of the systems when expressed in resistant strains may immensely contribute to biocide or antibiotics resistance. Antimicrobial components are released by the RND systems and these include first line anti-pseudomonal drugs such as beta-lactams and beta-lactamase inhibitors (Poole, 2011). Furthermore, alteration or loss of the outer membrane porin protein OprD is yet another common mechanism of resistant to carbapenems(Wang, et. al. 2010). Since P. aeruginosa infections are usually treated by the use of fluoroquinolone (Ciprofloxacin), its high level resistance is as a result of mutations in the DNA gyrase and topoisomerase IV enzymes, which target these antibiotics. Outbreak of P. aeruginosa An outbreak can be defined as two or more sterile site isolate of the same species, with the same antibiogram, from different babies within the space of two weeks. A Pseudomonas aeruginosa infection outbreak on neonatal intensive care units reflects a degree of breakdown in infection prevention measures. Poor hand hygiene, low nurse: patient ratio, inadequate spacing between cots, overcrowding, environmental colonization (especially of water systems), inadequate cleaning of common use equipment, injudicious use of antibiotics, particularly broad spectrum and prolonged courses and delaying the introduction of material breast milk, all contribute to the emergence of outbreaks. It has been reported that infection from P. aeruginosa usually occurs 48hrs after birth, which affects two to three per thousand babies in the UK (Walker, et.al. 2013). The occurrence of the infection is even higher in those born prematurely or with surgical conditions (Durojaiye, et.al. 2011). Microbiological analysis In previous studies, (Walker, et.al. 2013) carried out the following microbiological investigations. Dismantling of Taps Taps and flow strengtheners from relevant hospital were dismantled, categorized into components, swabs and water samples were also taken. Samples for microbiological assessment were placed in 10 ml of maximum recovery diluents together with 10 sterile glass beads (3 mm diameter, VWR International, Lutterworth, UK). The surface of each component was scraped with a sterile plastic loop (Sterilin, Newport, UK) and the suspension was then vortex-mixed (10 s) to remove biofilm and to suspend the micro-organisms. Each sample was then spirally plated (Don Whitley, Shipley, UK) on to plate count agar (Oxoid, Basingstoke, UK) and Pseudomonas selective agar (PCN, Oxoid, UK), for determination of aerobic colony count (ACC) and P. aeruginosa count respectively. This was then incubated at 30Â °C on (Plate Count Agar) or at 37Â °C (PCN) for 48 h. It was found out that complex flow straightener had significantly higher P.aeruginosa counts (P

Thailand Visit essays

Thailand Visit essays Thailand owns a rich cultural background, which has been molded by the own hands of its people. Its former name Siam means the Land of the Free, basically because it was not colonized by many foreign nations. Also dubbed the Land of Smiles because of its people, Thailand boasts of quick advance in technology, an increase in the rate of literacy, progression in economic status, and certainly, the high demand of its world-renowned products. The discussion of Thailand cannot be completed without the inclusion of Thai food because of its significance in many aspects of their society. Thai cuisine can be seen as one of the worlds most delicious because of its popularity in many countries. Thai cuisine is considered among the most internationally known dishes, with a unique blend of particular tastes: hot (spicy), sour (piquant), sweet, and always highlighted with citrus (lemongrass and lime). The rising recognition of Thai cuisine is due to the fact that most western people today are more health-conscious. Thai food is lighter and not as bulky as Western food. Moreover, the herbs and spices used as common ingredients have medicinal properties that come with them. Nevertheless, the common theme of all Thai meals is harmony-harmony in the taste and smell, as well the harmony of communal dining. During my two-week stay there, I was exposed to a new hodge-podge of dishes. One of my fears before the trip was the food, which I thought were all hot and spicy. But then, I saw [and tasted] how Thai food was not only limited to the zesty and fiery flavors. In fact, it was a jumble of different tangs, emphasizing on the sweet and the spicy still. I was able to stretch my otherwise miniscule knowledge on taste [since I am very picky and conservative with what I take in] because of their food. My palate was more than satisfied with the very delectable dishes they have such as the tom yam (sour and mildly spicy soup), gra thong-thong (crispy f...

Comparing John Locke and Thomas Hobbes

Comparing John Locke and Thomas Hobbes Free Online Research Papers Thomas Hobbes and John Locke were two of the greatest political and philosophical thinkers of their time and ours. Ideas like these have shaped governments throughout history and still hold true today. They had extremely different views on government, but the bases of their arguments were similar. They used reason to justify their ideas, rather than divine right. Although both men acknowledged that there was a God, He played a very small part in their ideologies. The philosophers each had an impact on the world. John Locke’s ideas influenced the United States Declaration of Independence, Federalist papers, and the Constitution. Thomas Hobbes’s ideas refuted England’s parliament. Hobbes and Locke agreed that some type of ruler would be necessary, whether it be an absolute monarchy or a form of democracy. Although Locke and Hobbes agreed on some subjects, the majority of their philosophies differed greatly, such as the type of ruler that they agreed was needed. Thomas Hobbes believed that a ruler with absolute control was necessary, while John Locke held that government should be at least partly be influenced by the people. Locke also believed that the people had the right and responsibility to overthrow their government if their needs are not being satisfied. On the contrary, Hobbes was more pessimistic. He believed in the Social Contract, thinking that once people handed their will to a ruler by putting them in power, that ruler had total power over them and could not be overthrown. Hobbes believed that this transfer of power was how man is able to get out of the state of nature and formed society. John Locke also believed in the social contract and the state of nature, but he opposed Hobbes’s position on these issues. Locke thought people could live in peace in the state of nature, because everyone was equal and had a conscience to guide them. Locke disagreed with Hobbes’s assumption that the state of war and the state of nature were the same. He felt that people could go without a leader by using reason in its place. The state of war would only occur when they tried to force things on each other. Locke thought that when that happened people had the right to wage war, as an act of defense. I feel that the reason the philosophies of Locke and Hobbes clashed is that their views of man kind were polar opposites. John Locke kept an optimistic view point, considering man kind good, independent, and equal from birth, and the choices made from then on to be able to change this image. He also felt that humans could only understand and sympathize with things that they had experienced, but also could learn from mistakes and interactions to improve themselves. Thomas Hobbes’s view point was very different. He reasoned that humans were not unlike animals, and were fearful and predatory. Hobbes held that man kind was evil and constantly in opposition to the rest of mankind. He also felt that humans had an innate motivation to feel pleasure and cause hurt. Research Papers on Comparing John Locke and Thomas HobbesAssess the importance of Nationalism 1815-1850 EuropeQuebec and CanadaCanaanite Influence on the Early Israelite ReligionComparison: Letter from Birmingham and CritoBringing Democracy to AfricaCapital PunishmentEffects of Television Violence on ChildrenThe Effects of Illegal ImmigrationUnreasonable Searches and Seizures19 Century Society: A Deeply Divided Era

Pay for Performance why it doesn't work in the Workplace Essay

Pay for Performance why it doesn't work in the Workplace - Essay Example To show the extensive use of the reward system, the author writes on using rewards to recognize teamwork, monetary rewards for employees for undertaking trainings and gaining new skills. The author states that rewards often impede than they enhance performance on many tasks with specific emphasis to those that require creativity with the example of Japan and Germany countries that do not use reward incentives and are successful in employee motivation. The other further explores the fact that there are no empirical studies linking motivation to rewards showing poor implementation of compensation systems. In fact, research by Jenkins in 1986 shows no relation between quality performance and rewards (p 124). In a case where incentives were withdrawn, production decreased then after sometime rose to reach a better level than when there were incentives further showing that incentives do not motivate workers for quality or higher productivity (p 124). The author then delves into the reasons for the failure of incentives including lack of necessity that is the introduction of incentives unnecessarily resulting in lack of any impact on performance. The second reason is secrecy where there is no transparency on each employees earning leading to overestimation and belief of differences in pay resulting in low morale and turmoil at the workplace. Other reasons are lack of match between performances and pay and expense in rewards solved via using noncash rewards. The other reason is too big versus too small incentives where small incentives do not have an impact while large ones are not received by all the workers resulting in failure of incentives to motivate performance. Short-term versus long-term incentives are the other reasons for incentives failure where employees may make decisions countering long-term interests when incentives base on short-term performance. Objectivity versus subjectivity,

A Thousand Years Of Good Prayers Essay Example | Topics and Well Written Essays - 750 words

A Thousand Years Of Good Prayers - Essay Example He has great concerns about the welfare of life of his daughter living in a distant land as a divorcee and feels that he can contribute something tangible to lighten her burden. His intentions are good, but not to the liking of his daughter! This retired man from Beijing travels all the way to visit her in Spokane, Washington. She is working there as a librarian. He plans to stay with her till such time, he thinks, she is able find peace through her trauma. The generation gap strikes! The daughter is not much enamored with the ideas of her father. Father is hurt with the negative approach shown by his daughter for his efforts to what he considers as the reconstruction of her life. In that town, he meets an old woman who has fled from Iran to USA, after the revolution. Both of them know not much of English but human emotions score over their own languages, and rare friendship develops between the two. They find a unique unexplainable horizon of hope in life, without knowing what exactly they want from each other, except striking the nearness through each other’s trials and tribulations. The daughter, influenced by the western culture has practical ideas. She wishes to remarry and gets ready for it with a Russian man. In the end, the old woman is sent to a retirement home and the father and the daughter come to terms. The relationship between the daughter and father is normally intimate. But this story reveals why it is different, due to the cultural gap between the two. The father arrives from the rigidly governed Communist China, and the social values are shaped accordingly as per the directions of the State. The position is entirely different in USA, where personal freedom is topmost in the agenda of governance. On the one side the people live with the damaged psyche, women silently bear the desperation of lost love relationships and on the other side new experiments in love-relationships continue to happen without any restrictions from the