radio-imaging effectiveness :: essays research papers

Radiation can be used in both diagnosis and therapeutic manners. The radiation emitted from radioisotopes can destroy tissue and in the therapeutic use: the destruction of cancerous and other dangerous tissues. And with diagnosis the gamma particle pass through the body tissues with minimal damage to a gamma camera. To evaluate the effectiveness of PET, SPECT, MRI and X-rays, we first need some basic knowledge on how each of them work. PET stands for positron emission tomography and works by an instrument collecting radiation emitted from a radioisotope injected the patient’ body. The strengths of emission are recorded by a gamma camera, which has a series of scintillation crystals, each connected to a photomultiplier tube. The crystals convert the gamma rays, emitted from the patient, to photons of light, and the photomultiplier tubes convert and amplify the photons to electrical signals. These electrical signals are then processed by a computer to generate images. The table is then moved, and the process is repeated, resulting in a series of thin slice images of the body over the region of interest (e.g. brain, breast, liver). These thin slice images can be assembled into a three dimensional representation of the patient's body Nowadays, PET scanning devices are most often used in conjunction with CT scanners, so that a more accurate image can be observed by the doctor for easier diagnosis of diseases or disorders. SPECT (Single Photon Emission Computed Tomography) works in a way much the same to PET. But the radioactive substances used in SPECT (Xenon-133, Technetium-99, Iodine-123) have longer decay times than those used in PET, and emit single instead of double gamma rays MRI has a more complex principle for its function; it works by creating a magnetic field so strong that the hydrogen protons in the body are forced into alignment with the magnetic field. Short bursts of radio waves are sent from the scanner into your body. The radio waves knock the protons from their position. When the burst of radio waves stops, the protons go back into position. They realign back to being in parallel with the magnetic field. As the protons realign, in a process known as relaxation, they emit tiny radio signals. A receiving device in the scanner detects these signals. The type of tissue can be interpreted from the strength of the signal emitted. Most of the hydrogen atoms in the body are in water molecules.

An Essay on “The Micromanager”

The case study entitled â€Å"The Micromanager† was written by Bronwyn Fryer, Jim Goodnight, Mark Goulston, Craig Chappelow and Michael Lawrie for the Harvard Business Review journal last September 2004.The fictional story was about a CEO of Retronics Corporation, George Latour. George believes that he is an exceptional leader and has a command to increase the company’s profits with a goal of excellence towards the software-engineering firm. Instructed by the board chairman, George hired a new marketing director, Shelley Stern, who, according to the chairman, only needs a bit of training in the software-engineering business. He does his best to bring Shelly up to date.George has her sit in on developer meetings, forced her to do client calls, and even has the finance office explain the company's financial affairs on her. George has tendencies to be meticulous, interfering with Shelly’s work, suppressing her creativity and suggesting his own â€Å"better† i deas. George also gives blind comments like when he said â€Å"Thanks, Shel. You're the best† although Shelly felt down that time when George repelled her creativity. Doing all this made Shelley unhappy and never seems to show interest. In truth, she sees George's management style as oppressive, making her awfully depressed. In the end, Shelly rebelled and accused George as a â€Å"micromanager†, while leaving George taken aback and could never believe what he heard.Both parties, George and Shelly, have some problems in terms of belief and character. As CEO of the company, George carries a lot of pressure on his shoulders that is why he tries his best to excel the demands of the firm since the company is not in a good shape. He overexerts himself by interfering with the work of his subordinates. Clearly, he lacks some sensitivity and trust to his underlings and makes the work done by doing it himself. George is uncomfortable with his job and thinks that the blame could only point at him that’s why he is afraid to accept radical ideas from his underlings.Shelly, on the other hand, is quite new to the business. Although she has the qualifications for the job, she still needs a lot to learn and needs to adjust spontaneously according to the demands of the firm and her boss. Shelly believes that she has good qualities and gives overconfidence on her work. She also thinks that her ideas are excellent and needs to be praised not criticized, as done casually by George. As a newly hired employee, she is pressured to show her good qualities to her co-workers and leave a good impression as a marketing director. Shelly trusts herself and believes that she can stand on her own without the help or intervention of her superiors.According to the U.S. Army Handbook of 1973, there are three general types of leadership. They are: (1) Authoritarian or autocratic style; (2) Participative or democratic style, and; (3) Delegative or free reign style. Authoritar ian or autocratic style is basically used when the boss tells his subordinates what he wants done and how he wants the job done without getting the advice or opinion of his subordinates. An appropriate condition to use this style is when all the information to solve the problem is provided, there is time pressure, and the subordinates are well motivated to accept hasty commands.Some narrow minded people think of this style as an excuse for yelling, using humiliating language, leading to threats and abuse of power. This is not the authoritarian style but rather an abusive, unethical style called â€Å"bossing people around†. Authoritarian style is normally used on rare situations when necessary. Participative or democratic style of leadership is preferred if time is more available and the leader wants to gain more commitment and motivation from the subordinates. This style includes the employees in on the decision making processes. However, knowledgeable and skillful employees should take part in the process and the leader affirms the final decision as a sign of authority.Using this style does not show weakness of the leader but rather a sign of strength and trust that the employees will respect. In delegative or free reign style, the boss allows the employees to make their own decision. This style is used when employees are able fully capable of analyzing the situation and can determine what needs to be done to solve a certain problem. Although the employees had the power to make decisions, the responsibility and final decision always lie on the leader himself.For a good leader to become more effective he should be able to use all three styles depending on the situation and the forces involved between him and his subordinates. The leader should know when and how to adjust to meet the demands of the firm as well as to maintain a good image to his employees. As for George Latour, he should improve on becoming a leader by listening more to develop more pro ductive ideas and to have a mutual relationship to his followers. He should not concentrate himself on how his employee sees him but focus on maximizing the available resources to have better and productive planning.The biggest problem for Shelly and George would be the lack of efficient communication. Most of the problems and conflicts that occur in a firm or organization are the direct result failure to communicate and misunderstanding. Faulty communication leads to confusion and can cause good plans to be unsuccessful. Communication is said to be the exchange of information or ideas from a sender to a receiver. (Communication and Leadership) Efficient communication happens if the receiver comprehends the information that the sender wanted to address. Open mindedness also plays a big part in communication. It sharpens the ability of the receiver to understand what the sender is saying thus making the communication process more efficient.Good communication is also hard to attain es pecially when there are some barriers that prevent the sender and receiver to understand each other. Some of these said barriers of communication are: culture, beliefs, noise, physical and mental stresses, past experiences, and environmental factors such as bright lights, unnatural sights, unattractive person or any stimuli that can cause distraction. (Communication and Leadership)For a good communication process to happen, both parties should overcome these barriers to have a more productive relationship with each other. In the case of George and Shelly, they must relieve themselves of the stresses that they carry so that they can communicate effectively. Shelly should exert herself on listening to suggestions and combining it with her creative ideas while George must also try to become more sensitive and to give more trust to his employees.References:Bronwyn Fryer, J. G. (Sep 2004). The Micromanager. Harvard Business Review 8p, 2c, 4bw , p31-40, 8p, 2c, 4bw.Communication and Leade rship. (n.d.). Retrieved August 27, 2007, from The Skagit Watershed Council Website: http://www.skagitwatershed.org/~donclark/leader/leadcom.htmlLeadership Styles. (n.d.). Retrieved August 27, 2007, from The Skagit Watershed Council Website : http://www.skagitwatershed.org/~donclark/leader/leadstl.htmlUnited States Army Handbook. (1973).

Albany Plan of Union Essay

A lot of uneducated people in today’s time think that the colonies always worked together before the French and Indian war. But sadly the people who think this are wrong. In fact the only connection between the colonies, other than the fact that they were all part of England, was through trade. With this loose connection there would never be any hope of defeating the French in the French and Indian war. But luckily Ben Franklin had a great idea to unite the colonies called the Albany plan of union. Even though it was not passed, the Albany Plan of union was a genius idea because it brought every colony under the control of one council, allowed the collection of taxes for military purposes, and united the colonies so that they could actually defeat the French. First off, throughout America the only thing governing the colonies besides England was each colony’s own colonial assembly. This kept each of the colonies very diverse and independent from each other. With the Albany Plan each of the colonies would be under control of a Grand Council, which would be headed by a President General appointed by the king. This would keep all the Colonies together and following one order. With this the Colonies could easy be ready for war if anything were to happen. Secondly, another big problem with the separated colonies was the fact that barely any money was sent to help the war effort. Without money for support there would be no way for supplies. Under the Albany Plan for Union, the grand council would have the right to collect taxes to go towards the war effort. One of the disagreements about this part of the plan was that the larger colonies became angry because they would be paying more taxes then the smaller colonies. This would prove to be Benjamin Franklin’s most daring part of his plan. Finally, one of the most important parts of this plan was that it united all the colonies as one. Before this plan the militia was state based and not very professional. Also state militia would not leave the boundary of their own state. This made the Militia weak and unable to defeat the French. With this union of colonies, the militias could come to the war in minutes earning them the nickname, Minutemen. In conclusion, The Albany Plan of Union was truly a genius idea. Each part f the plan was what the colonies needed to be united and to defeat the French forces. Sadly though, The Albany Plan of Union needed an approval from parliament and the colonial assemblies. In the end it was not passed because the British saw it as a threat and the Assemblies liked there power. Even though it was not accepted it was a great idea. Even though it was not passed, the Albany Plan of union was a genius idea because it brought every colony under the control of one council, allowed the collection of taxes for military purposes, and united the colonies so that they could actually defeat the French.

Different types of ultrasound transducers

Ultrasound transducers are prepared for a diversity of functions and can be custom made-up when required. Cautious attention must be paid while choosing the correct transducer for the application and it is vital to choose such transducers that have the preferred bandwidth, frequency and focus to optimize assessment ability. Mostly transducer is selected either to improve the understanding or resolution of the structure. Transducers are categorized into groups according to their functions.Contact transducers are used for through contact examination and are normally hand manipulated and contain elements confined in a rugged casing to endure sliding contact with a diversity of materials. These transducers encompass an ergonomic design so that they are simple to grip and go along a surface and frequently have replaceable put on plates to extend their useful time. Coupling resources of water, oils, grease or commercial resources are employed to eliminate the air gap involving the transduc er and the component being examined.Immersion transducers – These transducers do not contact the part, these are designed to function in liquid surroundings and all links are watertight. Immersion transducers generally have an impedance corresponding layer that assists to get extra sound energy into the water and in line, into the constituent being examined. These transducers can be acquired with a planer spherically focused or cylindrically focused lens. A focused transducer can advance the sensitivity and axial motion by focusing the sound force to a lesser area and are classically used within a water tank or as fraction of a bubbler structure in scanning applications.Contact transducers are obtainable in a diversity of configurations to advance their usefulness for a range of applications. A flat contact transducer is utilized in usual beam inspections of comparatively flat surfaces, if the facade is curved; a shoe that matches the bend of the fraction may necessitate to b e added to the facade of the transducer. If near facade resolution is vital or if an angle beam examination is required, one of the particular contact transducers illustrated below may be used.Dual element transducers – These enclose two separately operated elements in a particular housing, one of the elements broadcasts and the other accepts the ultrasonic waves. Energetic elements can be selected for their sending and receiving abilities to supply a transducer with cleaner waves. Dual element transducers are particularly well matched for making measurements in applications in the case where reflectors are extremely near the transducer, as this design removes the ring down consequence that single-element transducers practice.These transducers are incredibly useful when making width measurements of slim materials and also when examining for near facade defects. (NDT Resource Center, n. d. ). Delay line transducers – These offer versatility with a diversity of replaceab le choices; removable delay line, facade conforming casing and shielding wear cap alternatives can make a sole transducer efficient for a wide variety of applications. The main function of this transducer is to bring in a time delay among the generation of the sound signal and the influx of any reflected signals.This permits the transducer to end its sending job before it begins its listening purpose so that near facade resolution is enhanced. These transducers are created for use in applications such as elevated precision width gauging of thin resources and delaminating checks in compound resources. They are as well helpful in high-temperature measurement functions as the delay line gives some lagging to the piezoelectric constituent from the temperature. Angle beam transducers – These transducers and wedges are classically used to bring in a refracted shear signal into the test substance.Transducers can be acquired in a diversity of fixed angles or in modifiable versions. I n the fixed angle edition, the angle of refraction that is obvious on the transducer is only correct for a particular material which is typically steel. The angled sound pathway permits the sound beam to be mirrored from the back wall to get better detect capability of errors in and around welded surfaces. Normal incidence shear wave transducers – These transducers are exclusive since they introduce shear signals directly into a test part without the utilization of an angle ray wedge.Cautious design has facilitated built-up of transducers with negligible longitudinal wave infectivity. Paint brush transducers – Paint brush transducers are elongated and thin transducers and are prepared of a collection of minute crystals that are cautiously matched to reduce variations in recital and uphold uniform compassion over the complete area of the transducer. These transducers make it likely to scan a bigger area more speedily for discontinuities. (Piezo Technologies, n. d. ).

Benefits of using electronic whiteboards as a teaching aid Essay

Benefits of using electronic whiteboards as a teaching aid - Essay Example It is possible to maintain cleanliness in the environment while using whiteboards, as there are no chalks or dusters. Besides providing the convenience of using flipcharts, pictures, maps and charts during demonstration which otherwise would not have been possible, it mainly provides the following benefits: It serves as an excellent tool for brainstorming sessions, either in meetings or classrooms, the demonstrator has the benefit of conducting question-answer session in several ways, which after analyzing and ensuring that all pupils are taking part, uses symbols or communication aid to mark the answer as true or false or to transfer their views on whiteboard for display purpose. It is easy to get students' attention, as it is a colourful medium. Whiteboard is ideal in situations where the computer access is limited as it is an interactive tool, which works best when there is only a single computer in classroom. While working along with computer and projector and in addition to displaying lectures or information, it can also send that information to all students in a class and possess the ability to research a topic using Internet along with the class. Electronic whiteboards help in daily updating of lesson plans.

Eastern Philosopher Letter Personal Statement Example | Topics and Well Written Essays - 1000 words

Eastern Philosopher Letter - Personal Statement Example You see, Vishnu, you are different in a similar way as I was. You see beyond the immediate; you even surpassed me in some ways, such as your seeing the futility of the way of the ascetics. Your questions regarding them impressed me; I will not forget when you asked me how one can attain enlightenment when continually starving, dirty and begging. You inquired of the balance in your years with me (Moore-Bruder, 2005, p. 499). It is indeed the balance between desire and self-denial that is the key to the detachment that leads to the finer levels of consciousness. There must be an incredible awareness, an ability to see beyond this world our senses recognize and apprehend. The awareness directs the senses, not the other way around; this is where the teaching cannot be transferred from one person to another through words only. Words in and of themselves do not have any intrinsic meaning, yet the way they are delivered has an impact upon the mind that contemplates the words. Each mind is unique in its ability to transcend itself. By adhering to the Eightfold Path, one's mind unfolds and begins to align with nirvana (Moore-Bruder, p. 502). First one must become aware of desires and cravings of the senses, which are the primary receivers of the mind. It is only when the mind is stilled and the senses are fully awake, hence overcoming their cravings, that one can begin to comprehend nirvana. This is what is most difficult to communicate with people, and this is what makes you weary. As we grow and develop, our thoughts and cravings form a unifying force that is very powerful in the physical realm. It is this force that is the fuel of life for most people and they do not or cannot know any different. Once the path to enlightenment, true enlightenment, begins, there is no way back to the limited mind with its busy activities and desires and plots for gaining more and more material things. Power and glory become dust in the winds of time and one can begin to feel separated from humanity as you expressed in your letter. Know that this, too, is an illusion.

Intro to Visual Arts Essay Example | Topics and Well Written Essays - 500 words

Intro to Visual Arts - Essay Example She is very appealing with her nipples erect and fixated on her chest due to her laying position. She covers her genital area with her left hand just by a glimpse of her fingers. On the right hand, she is holding a cluster of red flowers and one flower fallen on the bed cover. She lies sensually with her legs crossed. A dog is sleeping on the edge of the bed on the covers. At the end of the room are housemaids, one is kneeling down with head inside a suitcase and the other standing beside her. This painting falls in the category of fine arts. The painting has aesthetic qualities; conceptual qualities of viewing art object as being beautiful and having a good taste. Venus has qualities that are capturing and enlightening to the viewer to judge the painter of having a good taste. This quality differentiates it from popular arts. The Venus of Urbino painting portrays private and domestic function of a woman as a sexy goddess who is appealing to her husband. It also portrays the need of a woman to remain seductive and appealing to her husband. (Lazzari, Schlesier 22-25) It is for marital significance for the eyes of the husband only. The painting is intended for personal and private use of the owner. The line element portrayed on the crisis folding of the covers gives textural contrast of the cover. Line element reveals the well-defined body mass and volume of the woman. The floor patterns outline line element as a well coordinated and liberate space to show the harmonization of the room and social class taste of the residing people. Light element is used to demonstrate the illusion that the nude Venus is appearing to closer people than people behind (Lazzari, Schlesier 22-25). The dark wall behind her is able to bring contrast between the woman and the wall clearly to portray her body structure and formation without straining. It also brings emptiness on the dark background. On the window, light element is used to portray the