Investigating Electromagnets Essay Example for Free

Investigating Electromagnets Essay When a current passed through a wire it causes the wire to have a magnetic field. If the wire is coiled it behaves like a bar magnet. The stronger the magnet the further the field lines reach. If you place an iron core in the coil of wire the magnet becomes stronger. Hypothesis: I think that if I pass current through a coil of wire, the coil of wire will become a magnet. I think this because the electrons are flowing through the wire and this causes the wire to become magnetic. I predict that if you increase the voltage, the magnets strength will increase and the magnetic field will get bigger, this is because Ohms law = V=IR, so if you increase the voltage, the current will increase. If the coil of wire has a resistance of 1 ohm and you pass volts through the wire, the wire will have a current of 6 amps. The second method that I predict which would affect the strength, is to place the coil around the nail. Also, if you increase the number of coils around the nail, this will also increase the strength of the magnet. The magnet can affect the randomly arranged domains by arranging the domains in line. The stronger the magnet, the more domains will be affected and put in line making the iron a magnet. I also predict that if I double the current the magnetic field will double. i. e. The strength of the magnet will be directly proportional to the current. Method: Equipment: Power pack, compass, wire (for coil), nail (iron), ammeter, 2 crocodile clips, ruler, extended wires. Diagram:   Set up the equipment as shown above. Make sure the equipment is set up correctly and there is the right amount of coils on the piece of copper. Also make sure everything is working.   Place the compass about a metre away from the coils.   Turn the power supply on and increase the voltage until the ammeter reads 0. 1 Amps. Move the compass towards the coil of wire. Use your finger to do this. When the compass moves or makes a sudden turn stop applying force to it. Then measure the distance between the coil of wire and the compass. Record the result and repeat this 3 times. After you have repeated this 3 times you change the current to 0. 2 Amps.   You then do the same process for what you did for 0. 1 Amps, this makes the test fair. Results table: Size of the field (mm) Test number Current (Amperes, A) Conclusion: My results support part of hypothesis. In my hypothesis I said that if I increase the current the magnetic field will increase, this is shown on my results table. The second part where my results support my hypothesis is that when a current passes through a coil of wire, it will become a magnet and when the current is stopped the coil of wire will become non-magnetic. Some parts of my results dont support my hypothesis, as I predicted that if I double the current the magnetic field would double. From my graph I can see at 0. 1 amps the field is 35, so if I were to double this I would get 70 but for 0. 2 amps I got 67. 33, so from this you can see that if I double the current the magnetic field does not double. The current is directly proportional to the magnetic field because it is a straight line. Evaluation: My results are reliable because I used the same equipment throughout the experiment. I also repeated my method 3 times, so I could get a fair average. I also made sure I kept the same number of coils of wire throughout the experiment. I also did the experiment in one day, therefore the room temperature was the same. These are the reasons why my test was a fair test; therefore the results I got were reliable. There was a problem when I did the test. The problem is, when the current and resistance get too high, the circuit gets hot and then trips out. This can affect the results because when the circuit gets too hot, and the resistance gets higher, the current or p. d. that is passing through, will be less than what it should be, therefore the magnetic field will be smaller than what it should be, because of this the results will be different. To solve this problem we might have to use thicker wire. We could also use shorter wire, Doing these would make the results more accurate. Another way we could solve the problem could be to let it cool down after it trips out. Another problem when doing this experiment is that the compass could be affected by the other groups magnetic field, this is because everyone was working at the same time. A way to solve this problem could be, to do the experiment at different times, like one after the other. Or you could do it in different rooms.

Principles of Managers and Management

Principles of Managers and Management We must understand who is manager before further our study into the aspects of management. Managers have long been responsible for planning, organizing, leading and controlling in such a way as to ensure that the organizations objectives are achieved efficiently. A major change is occurring in many organizations, however Management is increasingly becoming a responsibility of every individual in the organization, not just those who are formally designated as managers. In many organization, all members are managing themselves more than was generally in the past. They are performing some of the functions of management, such as planning, not simply the task assigned to them as part of the organizing process. 1.1.2 Who are managers? Manager can be defined as, A manager is an individual who is directly responsible for ensuring that tasks are performed by people or employees in an organisation. or A manager is a person tasked with overseeing one or more employees or departments to ensure these employees or departments carry out assigned duties as required Practically, managemer is divided into three levels, 1) Senior / Top managemer 2) Middle manager and 3) First level / Lower manager. Top managers, who are responsible for making ornagization decision and establishing the plan and goals that affect the entire organisations. These individuals typically have titles such as Executive Vice President, Vice President, President, Chief Operation Officer (COO) or Chief Executive Officer (CEO). Senior or Top manager commonly consists of a board of directors or shareholders who own the company and are responsible for making key decisions that affect the company. Middle managers include all levels of management between the first level manager and top level of the organisation. These managers manage the work of first-line managers and may have titles such as regional managers, project leader, plant managers or division managers. First-line managers, the lowest level of management, manage the work of nonmanagerial employees who typically are involved with producing the organizations products or servicing the organizations customer. There are three key elements to get to know about the manager. The fuctions performed by managers in the management environment, roles and the skills. This three key elements will be discussed later. 1.1.3 What is management? Self check : In your opinion, what is the definition of management? Management can be defined as follows: Management is defined as the process of overseeing and coordinating resources efficiently and effectively in line with the goals of the organisation. The attainment of organizational goals in an effective and efficient manner through planning, organizing, leading and controlling organizational resources In the simplest of terms, management is all about getting things done. However, it is the way and the process of how one achieves ones target or goals and it is in this respect that management is considered an art and a science as well. Peter Drucker (1993) defined management as Supplying knowledge to find out how existing knowledge can best be applied to produce results is, in effect, what we mean by management. But knowledge is now also being applied systematically and purposefully to determine what new knowledge is needed, whether it is feasible, and what has to be done to make knowledge effective. It is being applied, in other words, to systematic innovation. (Drucker, 1993) From all the above definitions, it is clear that management is a creative as well as a systematic flow of knowledge that can be applied to produce results by using human as well as other resources in an effective way. Management has not been limited to managing human resource; management today has been segregated into various branches like financial management, strategic management, operations management, time management, crisis management, marketing management etc. Each of these is a separate branch that is being handled by managers who specialize in these fields. Today the importance of management from an organizations point of view has increased multifold. It is only through effective management that companies are developing and executing their businesss policies and strategies to maximize their profits and provide with the best of products and services. Management today combines creative, business, organizational, analytical and other skills to produce effective goal-oriented results! Some of the key functions in management includes learning to delegate, planning and organizing, communicating clearly, controlling situations, motivating employees, adapting to change, constantly innovating and thinking of new ideas, building a good team and delivering results which are not just figure -bound but results that also focus on overall growth and development. Management focuses on the entire organization from both a short and a long-term perspective. Management is the managerial process of forming a strategic vision, setting objectives, crafting a strategy and then implementing and executing the strategy. Management goes beyond the organizations internal operations to include the industry and the general environment. The key emphasis is on issues related to environmental scanning and industry analysis, appraisal of current and future competitors, assessment of core competencies, strategic control and the effective allocation of organizational resources. Nevertheless, based on definition number 2, effectiveness is the attainment of goals that enables the realisation of the objectives of an organisation or, briefly, as doing the right thing whereas efficiency is performing a job using minimum effort, cost and wastage or simply put as doing things right. The end result of an efficient and effective management is the success of an organisation. A person can be described as efficient but not effective or effective but not efficient in managing a specific task. Both elements are not interdependent. Lets say a factory worker finds a shortcut to doing a task with lower cost but by doing so, he deviates from the ethical objectives of the organisation. For example, he disposes of production waste by dumping it into the river. But one of the organisations ethical objectives is to preserve local harmony. So, the factory worker, through his action, deviated from the objective although he was efficient. In short, he was efficient but not effective. In contrast, an employee is considered effective but not efficient if he uses an old method to resolve a management issue even if it could have been resolved efficiently without deviating from the objectives of the organisation. For example, in delivering information, the employee sends a letter via post instead of e-mail. Although it does not affect or clash with the organisations objectives, the employee has wasted a part of the resources allocated to him. Both efficiency and effectiveness cannot be excluded from the definition of management as these are essential elements in defining management. 1.1.4 What is organizations? When two or more people get together and agree to coordinate their activities in order to achieve their common goals, an organization has been born. There is really no doubt about the present meaning of organization. Its purpose is to create an arrangement of positions and responsibilities through and by means of which an enterprise can carry out its work. An academic textbook definition of organization can be formulated as follows: a. the responsibilities by means of which the activities of the enterprise are dispersed among the (managerial, supervisory, and specialist) personnel employed in its service; and b. the formal interrelations established among the personnel by virtue of such responsibilities. It must be emphasized that an organization should not be seen as rigid as the term framework implies. In reality, almost all organization structures must be occasionally reviewed due to various changes in the external environment of the organization in question. Moreover, internal changes also occur oftentimes due to the development of various informal relationships. However, in order to develop a so-called science of organizations a conceptual framework of theory and principle must first be developed. It is true to state that principles of management have existed for a long time. These principles were not recorded as scientific truths, but simply applied as practical means to accompany the process of modernization. As societies became more complex, an acceptable framework to encompass the unscientific principles of management was needed. Since the nineteenth century, many writers and researchers have contributed a great deal to existing principles and accepted practices. It is in the formulation of principles that the science of management can be developed. A management principle distils and organizes knowledge that has been built up through experience and analysis. It is highly unlikely that management will ever become an exact science with many laws governing it because personal judgment will always be needed to supplement available knowledge. Unlike principles in the natural sciences, management principles are not fundamental truths, they are only conditional statements which largely depends on many other variables. However, it is still necessary to continue the process of understanding and applying accepted principles to improve the quality of day-to-day management practice. For this reason management will always be an art. 1.2 Who are managers and what they do? There are three key elements to get to know about the manager. Management Fuctions Management Roles Management Skills. 1.2.1 Management Functions Today in most management book, basic management functions The manager is involved in various basic activities. These activities are usually grouped in a concept categorised as management functions. These functions are illustrated as follows. Management functions Planning, Organising, Leading Controlling Referring to the table below, all four management functions elorated. Table 1.1: Management Functions Management Functions Descriptions Planning Defining objectives to be achieved for a given period and what needs to be done to achieve the objectives. All management levels in an organisation need to be involved in planning. Managers need to develop objectives in line with the overall strategies of the organisation. Organising Determining what tasks are to be done; who will implement and co-ordinate them; how the tasks are to be grouped; who reports to whom; and where decisions are to be made. The manager needs to logically and effectively organise the information, resources and workflow of the organisation so that he is able to react positively towards changes in the business environment. Leading This involves motivating subordinates; selecting the most effective communication channels; resolving conflicts; and directing as well as guiding the actions of others with the intention of achieving all objectives. The effective leader of today has to be visionary in foreseeing the future, sharing the vision and encouraging employees in realising the vision. Controlling The measuring of performance in all pre-determined objectives, determining reasons for deviation and taking appropriate actions, where necessary. Controlling is an important function in the management process as it provides ways to ensure that the organisation moves towards achieving its objectives. 1.2.2 MANAGEMENT ROLES Manager can identified by the role they play in the organisations. An expert in management, Prof Henry Mintzberg, did a research by observing what managers did during their work hours. His research conclude that managers not only have 4 elements as discussed in Management Functions, but they have to play another roles as detailed below (Lewis, P.S. et al; 2001). Role as a Figurehead A manager must carry out ceremonial duties. For example, the vice-chancellor of a university must be involved in the opening ceremony of programmes conducted at the university. The head of a department is responsible for entertaining his clients. Role as a Leader A manager indirectly functions as a leader. Each manager must function as a leader in motivating and encouraging his subordinates. The manager steers members of his unit to continuously work effectively to achieve the goals of the unit and organisation besides resolving problems and issues. Role as a Liaison Officer A manager conveys relevant information gathered to individuals outside his unit or to other relevant parties outside his organisation. The manager will allocate time for interacting with people outside his organisation. Thus, a manager acts as a channel for communications between his department and those within as well as those outside his organisation. For example, a human resource manager may liaise with the finance manager to check on funds allocated for the recruitment of new employees by the organisation before embarking on a recruitment drive. Role as a Spokesperson The manager of an organisation usually acts as its spokesperson. For example, a supervisor will usually ensure that the operations manager is furnished with the latest information on the running of his production plant. Similarly, the general manager of a factory will lobby local authorities for a new tender. Role as a Negotiator No organisation is without problems. A manager is compelled to find a solution for each of its problems regardless of complexities. The manager needs to spend a lot of time in discussions as he plays the role of a negotiator. For example, a manager will negotiate with the trade union chief to reach an amicable agreement on salaries. Role as an Initiator Two management experts, Sumantra Ghoshal and Christopher Bartlett (Dessler, G; 2001), highlighted the additional role of a manager as an initiator of corporate actions and transformations. Moreover, an excellent manager is one who cultivates three processes that steer his employees towards achieving initiatives for change. These processes are as follows: Entrepreneurship Process The manager will try to improve his units performance and when he gets a good idea, he will launch a programme to realise the idea. Researches carried out in Japan, the United States and Europe showed that a successful manager is one who focuses a lot of time and effort on steering his employees towards thinking like an entrepreneur. To meet this objective, the manager needs to empower, support and provide incentives for employees to attain self-direction. Capability Development Process In a technology-centred world, conglomerates need to fully utilise their advantage as a large establishment not only in matters of economies of scale but also in the aspects of widening and deepening the knowledge and abilities of its employees. A manager who succeeds will focus on creating a conducive environment that encourages employees to shoulder additional responsibilities. He will also focus on preparing the necessary training and guidance to build their self-confidence. The successful manager will allow employees room for making mistakes without the fear of being penalised while undergoing training and encourage them to learn from their mistakes. Reformation Process A successful manager will identify situations that might pose challenges to the strategies of the organisation and assumptions made. In other words, the manager is capable of cultivating a querying disposition such as why something is done in a certain way and whether there are alternative ways of doing it. 1.2.3 MANAGEMENT SKILLS SELF-CHECK 1.2 When an organisation shortlists employees for the position of a manager, it will usually select individuals with technical, interpersonal and conceptual skills. Therefore, the third approach to understanding the tasks of managers is to analyse the skills required to carry out the tasks. Figure 1.2 shows three types of essential skills required at each level of management. The arrow pointing upwards shows the type of skills that are needed by top-level management. The arrow pointing downwards shows the type of skills that are needed by lower-level management or line managers. Figure 1.2: Skills required of a manager (a) Conceptual Skills Conceptual skills refer to the ability to view the organisation as a whole, and the impact the different sections have on the organisation, as a whole and on each other. It also involves observing how an organisation adapts to or is affected by external environmental factors such as society, economic pressure, customers and competition. An efficient manager should be able to identify, understand and solve the various problems and critical perspectives. The need for conceptual skills becomes increasingly crucial when a manager climbs higher in the management hierarchy. (b) Interpersonal Skills Interpersonal skill is the ability to work well with other people. Managers with good interpersonal skills work more effectively in a group, encouraging other employees to input their ideas and comments as well as being receptive to the needs and views of others. The manager will also, indirectly, become a good listener and speaker. Interpersonal skills are crucial, regardless of the level of management. However, a low-level manager will be more occupied in solving technical problems while a manager at the middle and higher levels will be mainly occupied with dealing directly with others. (c) Technical Skills Technical skills are the ability to apply procedures, techniques and specialised knowledge required in a certain task. For a shoe factory supervisor, the technical skills required will include the steps involved in shoe manufacturing from the beginning until the final product is ready. A housing developers technical skills will include ways to complete the development of a housing estate. Technical skills are crucial for low-level managers as they supervise employees in manufacturing or service sectors. The manager needs to have technical knowledge and the skills to train new employees and assist employees in solving problems. Skills and technical knowledge are required to solve operational problems that cannot be handled by employees. Nevertheless, the higher the position of a manager in a hierarchy, the fewer the technical skills required. SELF-CHECK 1.3 Self check Based on what you have learned, identify the differences between the three levels and tabulate your answers. Exercise Explain each of the management functions that you have learned about. 1.3 HISTORY OF MANAGEMENT Scientific Management Theory (1890-1940) At the turn of the century, the most notable organizations were large and industrialized. Often they included ongoing, routine tasks that manufactured a variety of products. The United States highly prized scientific and technical matters, including careful measurement and specification of activities and results. Management tended to be the same. Frederick Taylor developed the :scientific management theory which espoused this careful specification and measurement of all organizational tasks. Tasks were standardized as much as possible. Workers were rewarded and punished. This approach appeared to work well for organizations with assembly lines and other mechanistic, routinized activities. Bureaucratic Management Theory (1930-1950) Max Weber embellished the scientific management theory with his bureaucratic theory. Weber focused on dividing organizations into hierarchies, establishing strong lines of authority and control. He suggested organizations develop comprehensive and detailed standard operating procedures for all routinized tasks. Human Relations Movement (1930-today) Eventually, unions and government regulations reacted to the rather dehumanizing effects of these theories. More attention was given to individuals and their unique capabilities in the organization. A major belief included that the organization would prosper if its workers prospered as well. Human Resource departments were added to organizations. The behavioral sciences played a strong role in helping to understand the needs of workers and how the needs of the organization and its workers could be better aligned. Various new theories were spawned, many based on the behavioral sciences (some had name like theory X, Y and Z). General Administrative Theories Administrative theory, Classical administrative theory An early form of organization theory, pioneered mainly by Henri Fayol (1841-1925), which was concerned principally with achieving the most rational organization for co-ordinating the various tasks specified within a complex division of labour (see his Administration industrielle et gà ©nà ©rale, 1916) . The translation of this book into English as General and Industrial Management (1949) implies that Fayol was concerned mainly with business management, although he himself makes it clear that his ideas about management were intended to apply to all formal organizations, including political and religious undertakings. Expressing the French administration as management has also led to the alternative designation of this approach as the classical school of scientific management. More recent exponents include Lyndall Urwick and Peter F. Drucker. Fayol, who is acknowledged to be the earliest advocate of a theoretical analysis of managerial activities, identified the key functions of management as being those of forecasting and planning. The most rational and efficient organizations were, in his view, those which implemented a plan that facilitated unity, continuity, flexibility, precision, command and control. Universal principles of administration were then distilled from these objectives. These include the key elements of the scalar chain (authority and responsibility flowing in an unbroken line from the chief executive to the shop floor); unity of command (each person has only one supervisor with whom he or she communicates); a pyramid of prescribed control (first-line supervisors have a limited number of functions and subordinates, with second-line supervisors controlling a prescribed number of first-line supervisors, and so on up to the chief executive); unity of direction (people engaged in similar activities must pursu e a common objective in line with the overall plan); specialization of tasks (allowing individuals to build up a specific expertise and so be more productive); and, finally, subordination of individual interests to the general interest of the organization. This list is not exhaustive, but illustrates the key proposition of administrative theory, which is that a functionally specific and hierarchical structure offers the most efficient means of securing organizational objectives (see M. B. Brodie , Fayol on Administration, 1967) Classical administrative theory, like its near-contemporary the scientific management approach, rests on the premisses that organizations are unproblematically rational and (effectively) closed systems. In other words, organizations are assumed to have unambiguous and unitary objectives, which the individuals within them pursue routinely, by obeying the rules and fulfilling their role expectations, according to the prescribed blueprint and structure. Moreover, in the attempt to maximize efficiency, it is only variables within that structure that need to be considered and manipulated. The interaction of the organization with its environment, together with the various factors which are external to the organization but nevertheless have consequences for its internal functioning, are systematically ignored. Clearly, both perspectives take a rather deterministic view of social action, since each assumes that individuals will maximize organizational efficiency, independently of their own w elfare, and with no thought for the relationship between the collective goal and their own particular purposes. The Human Relations Movement in organizational analysis, an otherwise diverse group of writers and approaches, is united by its opposition to precisely this assumption. Despite such criticisms, the classical theory of administration has exerted considerable influence on the fields of business studies and public administration, and it still provides the basic concepts which many managers use in clarifying their objectives. Question why they need evolution in the first place? What change the theory, From the start of the 19th century until the 20th century, managers and scholars formed a theoretical framework to explain what they believe to be good practices of management. Their efforts led to five different classes of perspectives on management classical, behavioural, quantitative, systems and contemporary. Each perspective is based on different assumptions towards the objectives of the organisation and human behaviour. Figure 1.3 will help you to understand the chronological sequence of the perspectives. You might be wondering why it is important and necessary to study the historical development or the evolution of management thought. Studying history enables us to learn from mistakes made in the past so as to avoid making them in the future. History also enables us to study past successes that can be emulated accordingly in the future. Most importantly, we must understand the reasons behind such occurrences in order to improve in the future. 1.4.1 Classical Perspective This perspective existed in the 19th century and early 20th century. It focused on the rational and scientific approaches to the study of management and on finding ways to mould an organisation to become more efficient. There are three sub-classes in this perspective, the scientific management, bureaucracy management and administrative management. (a) Scientific Management This approach existed at a time when productivity was deemed critical by businessmen. Businesses were growing rapidly but businessmen were facing a critical shortage of workers. Hence, management was continuously finding ways to improve the performance of its employees. The focus on improving employees efficiency is known as the scientific management approach. A number of researchers contributed towards the findings of scientific management, among them Frederick Winslow Taylor, Frank and Lilian Gilbreth and Henry Gantt. Frederick Taylor (1856-1915), a mechanical engineer, was of the opinion that problems arose mainly due to bad management practices and, to a lesser degree, problems with employees. He stressed that management itself needed to transform and that the transformation method could only be established through scientific research. He suggested that decisions based on rules of thumb be substituted with established procedures, after analysing each situation. Taylors theory, which stated that the productivity of the labour force could be improved through scientifically-based management practices, earned him the title Father of Scientific Management. To improve the work performance of employees, Taylor conducted a research entitled Time and Motions Study. From the research findings, Taylor identified five principles of management that could boost production efficiency. The five principles were: (i) Using the scientific approach to determine best practices and not relying on rules of thumb; (ii) Selecting suitable employees to perform a particular task. Suitability covers mental and physical aspects; (iii) Training and developing an employee so that he is able to perform a given task according to established procedures; (iv) Giving monetary incentives to ensure that employees perform a task accordingly; and (v) Reassigning all responsibilities pertaining to planning and organising to the manager. Taylor was not alone in this research. Henry Gantt (1861-1919), a friend of Taylor, focused on the control system in the scheduling of production. The Gantt Chart is still used today in planning the schedule of a project and has also been adapted in computerised-scheduling applications. The husband and wife team of Frank (1868-1924) and Lillian Gilbreth (1878-1972), also strived to further expand the scientific management approach. Lillian was a pioneer in the field of industrial psychology and contributed greatly to human resource management. She believed that if scientific management was widely utilised, the abilities of each employee would grow considerably. (b) Bureaucratic Management Bureaucratic management is an approach to management that is based on guidelines, hierarchy, clear division of labour as well as rules and procedures. Max Weber (1864-1920), a German social theorist, introduced many bureaucratic concepts. Among the components of bureaucracy are: (i) Authority and clearly defined responsibilities; (ii) Positions in an organisation that are structured according to hierarchy; (iii) Promotions based on qualifications; (iv) Records of all administrative actions and decisions to ensure continuity of organisational rules; (v) Separation of ownership and management; and (vi) Guidelines implemented to all employees without bias. The bureaucratic approach strives to increase efficiency and ensure continuity of overall operations of the organisation. This approach differs from scientific management, which only focuses on the employee as an individual. Nevertheless, this principle, used to improve efficiency, also may cause inefficiency. Rigid guidelines create red tape and slow down the decision-making process, resulting in the inability to change swiftly to adapt to the needs of the environment and, at times, create conflicts in performing a task professionally. (c) Administrative Management The administrative management principle focuses on the organisation as a whole. Among the contributors to this approach are Henri Fayol, Mary Parker Follett and Chester I. Barnard. Henri Fayol (1841-1925), a Frenchman, is considered the pioneer of administrative theory as he introduced the organisational principles and administrative functions. His most relevant contribution was presenting the definition and roles of an administrator. Fayol defined administration and management as planning, organising, directing, coordinating and controlling. He identified 14 principles of management: Division of labour: This is a concept on specialisation of work, based on the assumptions that: No one can do all the work; Each job requires different skills; and Repetition of work will increase efficiency. Authority: The right to give directions and power to be complied with. Here, authority at the office has to be differentiated from personal authority. Discipline: Based on respect and conformity. Unity of command: An employee should receive instructions from one superior only. Unity of direction: One superior and one direction for a particular activity with the same objective. Subordination of individual interests to the general interests: Personal interest should not exceed or precede over common interest. Remuneration: Salary payment based on various factors. Centralisation: The centralisation of work depends on th

Inhibitory Or Excitatory Potential Changes :: Biology Biological Papers

Inhibitory Or Excitatory Potential Changes Graded potentials can be either hyperpolarizations (inhibitory) or depolarizations (excitatory). Inhibitory postsynaptic potential, also referred to as IPSP, is the temporary hyperpolarization of a membrane. An inhibitory postsynaptic potential occurs when synaptic input selectively opens the gates for potassium ions to exit the cell (carrying a positive charge with them) or for the chloride ions to enter the cell (carrying a negative charge with them). Inhibition is not just the absence of excitation, it is an active brake that is able to suppress the excitatory responses from occurring (Kalat, 2004). Excitatory postsynaptic potential, also known as EPSP, is a graded depolarization. As a result of sodium ions enter the cell, excitatory postsynaptic potential occurs. As a result of the synaptic activation, the sodium gates open, allowing an increase in the flow of sodium ions crossing the membrane. Excitatory postsynaptic potential is a subthreshold event that decays over space and time, meaning its magnitude decreases as it travels along the membrane (Kalat, 2004). Lithium has both inhibitory and excitatory features. Evidence has shown that lithium alters sodium transportation (http://www.mentalhealth.com). In the extracelluar fluid lithium may replace sodium. During the process of depolarization lithium has an extremely rapid intracellular influx. Although, it is not effectively removed by the sodium-potassium pump. According to Kalat (2004) the sodium-potassium pump, "[is] a protein complex that repeatedly transports three sodium ions out of the cell while drawing two potassium ions into the cell" (p. 41). As a result, it prevents the cellular reentry of potassium. This interferes with the electrolyte distribution across the neuronal membrane, resulting in a decrease in the membrane potential, changes in conduction and neuronal excitability. As measured by cortical evoked potential, for humans lithium alters the excitability of the central nervous system (http://www.mentalhealth.com). Lithium enhances the uptake of norepinephrine and serotonin into the synaptosomes, thus reducing their action. Lithium also reduces the release of norepinephrine from synaptic vesicles and inhibits production of cAMP. "Lithium inhibits the synthesis of cAMP by the adenylyl cyclase in many brain regions, including the cerebral cortex, caudate, and hippocampus, but not the brain stem or cerebellum" (Feldman, Meyer & Quenzer, 1997). "The inhibitory action of lithium on NE-sensitive adenylyl cyclase is a consistent finding, but lithium clearly has distinctive effects on the adenylyl cyclase that is coupled with receptors

Epic of Beowulf Essay - The Value System in Beowulf :: Epic Beowulf essays

The Value System Revealed in Beowulf  Ã‚   Beowulf is a deeply serious commentary on human life with the main characters embodying a pronounced and coherent set of values. They are also the representatives of the outlined code for conduct and behaviour of those times. Honour, generosity and trust may seem to be the key words in the code. The protagonists reiterate in actions and words a belief in the importance of generosity of spirit and self awareness that make man a responsible member of the society. Beowulf secures the future of his thanes, in case of his death, not leaving them up to their own fate. He proves that in the warrior society, human relationships must be based on mutual respect and trust rather than subordination of one man to another. A warrior vowing loyalty to his lord becomes a voluntary companion more than his servant, taking pride defending him and fighting in battles. In return, he receives affectionate care and rich rewards - e.g. seen in Hrothgar’s attitude to Beowulf’s achievements. The relationship between the relatives is also a part of the outlined characteristics of conduct - if a person was killed, a relative was obliged to kill the slayer or execute the wergild (â€Å"manprice†), even if the killing was accidental. In fact, the money was less important than the actual carrying out of the kinsman’s duty. â€Å"It is better for a man to avenge his friend than to much mourn† – states Beowulf firmly, reiterating the weight attached to the moral responsibilities rather than attention drawn to the materialistic possessions. They were valued highly - the treasure gained in battles improved the well being but it was more of a common factor spiritually uniting the warriors and allowing them to fully realise their potentials. Still, family was the priority. King Hrethel (‘grandfather’ of Beowulf), however, may exemplify a clash in following the code and set values. One of his sons accidentally killed another; by code of kinship king Hrethel was forbidden to exact compensation from a kinsman, yet by the same code he was required to do one in order to avenge death. He was trapped in a situation without a moral way out and therefore Hrethel refused to face life any longer. Marriage also appears to be a part of the general code. It was a form of alliance between the fighting tribes e.

Workers? Compensation Essay -- essays research papers

  Ã‚  Ã‚  Ã‚  Ã‚  Workers’ compensation is meant to protect employees from loss of income and to cover extra expenses associated with job-related injuries or illness. Accidents in which the employee does not lose time from work, accidents in which the employee loses time from work, temporary partial disability, permanent partial or total disability, death, occupational diseases, noncrippling physical impairments, such as deafness, impairments suffered at employer-sanctioned events, such as social events or during travel to organization business, and injuries or disabilities attributable to an employer’s gross negligence are the types of injuries and illnesses most frequently covered by workers’ compensation laws. Since 1955, several states have allowed workers’ compensation payments for job-related cases of anxiety, depression, and certain mental disorders. Although some form of workers’ compensation is available in all 50 states, specific require ments, payments, and procedures vary among states.   Ã‚  Ã‚  Ã‚  Ã‚  Certain features are common to virtually all programs: The laws generally provide for replacement of lost income, medical expense payments, rehabilitation of some sort, death benefits to survivors, and lump-sum disability payments. The employee does not have to sue the employer to get compensation. The compensation is normally paid through an insurance program financed through premiums paid by employers. Workers’ compensation insurance pr...

How does Shakespeare create sympathy for Macbeth in the play? Essay

In the play Macbeth is portrayed as a tragic hero whose injudicious actions led by his vaulting ambition has resulted in a fatal ending which helps in creating a great deal of sympathy for Macbeth. Firstly Shakespeare creates sympathy for Macbeth through his more ambitious wife Lady Macbeth. She plays a major role in creating sympathy for Macbeth as she insults his masculinity be saying â€Å"Was the hope drunk Wherein you dress’d yourself ?†,which gives Macbeth no other option but to follow her. Shakespeare’s of rhetorical questions conveys how Lady Macbeth is manipulating Macbeth to kill Duncan. This for the Shakespearian audience would be quite shocking as she verbally bombards a soldier who was supposed to be really manly and aggressive, but Macbeth doesn’t really say anything back to her which is showing how he is been controlled by her. Furthermore, she uses personification which is another of her manipulative skill which reminds him about his ambition to be the Thane of Cawdor because drunken people often forget things. The audience see Lady Macbeth do this several times during Act1 scene 7 when she insults his sanity. For example, she says to â€Å"screw† his â€Å"courage† which leaves Macbeth to be feeble and accede what Lady Macbeth say him to do. Secondly, Shakespeare presents Macbeth as a victim of the scary encounter of Banquo’s Ghost. Firstly Macbeth ordains the ghost to â€Å"never shake Thy gory locks at him!† when he first catches the sight of the ghost. Macbeth’s use of the imperative his fatal attempts to take control of the supernatural, revealing a glimpse of the brave soldier the audience meet at the beginning of the play. He uses abominable imagery which portrays the disgusting and scary looks of the ghost as the audience wouldn’t be able to see the ghost i n the play. Furthermore the use of exclamation mark depicts Macbeth’s horror and fear, this is ironic as he was the one who got Banquo Murdered, also Shakespeare presents Macbeth as overthrown by Banquo and that Banquo was supposed to be the king as in the stage direction it says that Banquo ghost is sitting in Macbeth’s place ,showing how Macbeth doesn’t deserve his place making him an outcast rather than a powerful king. Furthermore, Shakespeare portrays how Macbeth is an ordinary man who is desperate for more normal life. Macbeth mentions how he wants â€Å"love, obedience, troops of friends† which lacks in his life. He uses long sentence filled with a list of things a king would have had and also which a are really essential for every human. Macbeth’s use of the word ‘obedience’ which he once had when he was a loyal soldier, recalling his past gives a glimpse of Macbeth’s regret over his nefarious actions. In addition, this is showing that he is tired of living the way he is and suggesting his love for lady Macbeth which has not returned to him as the audience can’t see this throughout the play. Moreover, when he finally loses Lady Macbeth when she kills herself, audience can then see that his chance of getting â€Å"love† is lost as he has lost everything he has. Moreover, Shakespeare creates a contrast between ‘noble Macbeth’ at the beginning and ‘devil Macbeth’ toward the end of the play when Macbeth has become an odious tyrant who doesn’t show any remorse in even killing his own best friend or even killing innocent Macduff’s baby. Shakespeare gives Macbeth a title â€Å"noble Macbeth† which not every soldier or king would often get he and he receives this by the king himself. He goes against the divine rights of a king which states how a king is equal to god but Macbeth goes against this with the help of his wife Lady Macbeth even though his conscience reminding him that he was overstepping the mark. Shakespeare’s use of diabolical imagery is taking the reference of how devil who was initially a really good angel but because of his pride and going against god he was forcefully sent to hell, likewise Macbeth’s was initially a really good person but because of bad influence he is turned into the person he is. Shakespeare makes so many biblical references of Macbeth forced being like the devil throughout the play like when Lady Macbeth says him to be the ‘serpent underneath’which is a reference to the snake in the creation story, which helps the audience refer to this and understand more easily as they would have really similar to these concepts. In conclusion with the use of Lady Macbeth Shakespeare creates sympathy for Macbeth as she was the one who first heightened his ambitions. He knows and relishes what is good, but he has chosen the opposite making his life a tragedy.

Education Has the Power Essay

A great scholar named Bacon once said â€Å"Knowledge is power.† How do we obtain knowledge? How do we effectively use it? The answer lies in education. The development and maintenance of a country is in the hands of its people. The people need to be educated to make beneficial decisions that would promote economical prosperity for their country. This essay will discuss why education is the single most important factor in the development of a country. First and foremost, a country strives to develop economically and sustainably. There is increasing demands for talented individuals to advance in every field to meet this development objective. These individuals need cultivation to find and develop their talents. Through education, individuals are provided with sufficient information and resources for advancements in their fields; making significant contributions to the economy of the country. Education has a tremendous influence on the civilization of a country. Education provides individuals with knowledge to question conscience, identify the good and the bad, analyze the mistakes of history, and make beneficial decisions. Thus, developing positive character attributes, decreasing the negative road blocks of a country’s development (e.g. crime), and preventing citizens from becoming criminals. As well-educated parents pass on their dignity to future generations, education sustains a system of significant contributions to a country’s society. On the other hand, education could serve as a source of economical growth for a country. Well established educational facilities attract students from all over the world to study in them. These students contribute to local markets by consumerism and by paying tuition. After graduating, many students may choose to stay and contribute to the country because they have settled. By investing in educational facilities, the country is able to profit from young intellectuals who would contribute to the country’s development. Education is the most fundamental factor in the development of a country. When people talk about a country’s development, they often refer to the country’s economical growth, induced by the structures of political, technological, and foreign affair systems. Education inspires intellectuals and innovation that will sustain and advance the country’s economy. There’s a famous proverb stating â€Å"If you give a man a fish you feed him for a day, if you teach the man to fish you feed him for a lifetime†. This proverb supports the fact that knowledge leads to sustainable development. Education is a worthwhile investment in human capitals that consequents to significant contributions for the sustainability and advancements in a country’s technology, health, economics, politics, and culture. In conclusion, education is not only the single most important factor in the development of a country, but it is also the most fundamental factor. After all, you wouldn’t see progress or profit from uncultivated workforces, would you?