Assessment Worksheet Essay

1. What section of the SOX compliance law requires proper controls and hence, security controls, to ensure the confidentiality and integrity of financial information and recordkeeping within an IT infrastructure? Explain the information contained in this section. SOX Section 404 mandates that all publicly-traded companies must establish internal controls and procedures for financial reporting and must document test and maintain those controls and procedures to ensure their effectiveness. The purpose of SOX is to reduce the possibilities of corporate fraud by increasing the stringency of procedures and requirements for financial reporting. 2. Who is Richard Scrushy and why is he relevant to SOX? Richard Scrushy first CEO charged with violating the SOX Act. He was owner and founder of HealthSouth Corp 3. Who, under SOX, is legally accountable for certifying and approving the integrity of the company and its financial reporting to the SEC and other financial organizations? Under the Sarbanes-Oxley Act, the CEO and CFO of publicly traded companies to certify the appropriateness of their financial statements and disclosures and to certify that they fairly present. 4. What is the difference between a form 10-K and a form 10-Q, and who must submit these to the Securities Exchange Commissions (SEC) for publicly traded company financial reporting? 10-K is a company’s annual report that is filed yearly & make public. 10-Q is the company’s quarterly report. Upper management of major companies is to submit these to the Securities Exchange Commissions. 5. What qualifies as a â€Å"large accelerated filer,† and how long after the end of the quarter do they have to fi le their quarterly financial report? A company that meets conditions of a million dollar amount has been subject to periodic reporting requirements pursuant to Exchange Act Sections for certain amount of time, has previously filed at least one annual report pursuant, and is not eligible to file â€Å"Small Business† forms. They have75 days after the end of their quarter they have to file their quarterly financial report. 6. Where would someone go in order to find the quarterly and annual reports for a publicly traded company? A person would go to a company’s webpage to find quarterly and annual reports for publicly traded company. Each company  should have an investor relations section. 7. Go into the Edgar Database and find the most recent 10K or 10Q for Microsoft, Nike, and Cisco. Who signed off on the 10K for each of those companies? Microsoft: Assistant Director, Nike: Assistant Director, and Cisco: Assistant Director. 8. What are some of the criminal penalties for falsifying documents, or covers up information related to financial matters and SOX? Some of the criminal penalties for falsifying documents or cover ups information related to financial matters and SOX are imprisonment. Imprisonment varies on situation. 9. What is the Japanese version of SOX, and what agency oversees its implementation? JSOX is the Japanese version of SOX. This is overseen by ULVAC Technologies. 10. Of what was Dennis Kozlowski convicted, and how is it related to SOX? Dennis Kozlowski was convicted for crimes related to authorized bonuses, purchase of art, and other high cost money involvement. It’s related to SOX because fraud for public companies. 11. What is the link between SOX compliance law and information systems security? Section 302 and 404 even though they do not mention IT 12. What sections within SOX compliance law pertain to needing proper internal controls? Section 302 and 404 are needed for proper internal controls to be in compliant with SOX. 13. Explain how these sections within SOX compliance law require proper security controls as it relates to having internal controls. The need for strong internal controls is not limited to public companies, however. Effective internal controls provide all management teams with repeatable and reliable information tools that allow them to identify, manage, and mitigate risk on an ongoing basis 14. Why are Vice Presidents and other executive managers who are privy to financial performance data considered insiders to a publicly traded company as defined by the Security Exchange Commission (SEC)? They would be considered insiders because of the information they have from internal resources. 15. True or False. SOX compliance law now holds CEO’s and CFO’s of publicly traded companies accountable for their actions as officers in a publicly traded company.

Consumer Durables and Nondurables

Analysis The definition of consumer durables and nondurables Consumer durables involve many kinds of products that is purchased by consumers, it is manufactured for long-term use. Such as: car, furniture and so on. But consumer nondurables are opposite. It is expendable goods purchases by consumers for their daily or short-term use. Such as: clothing, shoes and so on. The characteristics of consumer purchase Because of consumer durables has long-term use, and comparing with consumer nondurables, price is higher, so consumer purchase behavior is more cautious. There are some reasons. First of all, much more selectivity cause consumers are hard to make decision. Secondly, because of there are a lot of different brand, so they will carefully compare the various brands of cost performance, generally, consumer focus on the quality, service, and brand reputation. Finally, consumers can not buy from nearest store, they are willing to go to large scale shopping malls. But consumer nondurable is opposite. There are some features of consumer nondurables. Because of nondurables goods are short-term use, it can be daily product, such as towels, soap and so on, so consumer is willing to buy those at nearest store. Also, it can be visual product, when consumer decide to buy it, they might be affected by packing and store’s ambience, which means consumer can make decision easily. On the other hand, consumer has less loyalty for brand, they usually change same product with different brand. So we can sum up some features about consumer purchase habit, which are easy, fast, impulsive and emotional. Main characteristics of market Consumer durables: For product advertising strategy, company usually focus on product exhibition and display as much as possible, also they must have a large scale warehouse for inventory Consumer nondurables: For advertising strategy, Company is willing to choose outdoor billboards in the down and some crowded place, or promote on the internet. They don’t need large size warehouse for inventory.

Self leadership development paper Essay Example | Topics and Well Written Essays - 750 words

Self leadership development paper - Essay Example I think your key strengths is being hardworking and God fearing. Since I knew you when you were attached to our company, you always worked hard and demonstrated good morals and ethics. Although you are quite ambitious, I think you can do better if you consider wise counsel from your elders. As my favorite classmate, I think your best strengths are being confident in what you do, courageous and easy to approach. However, I think you should work on your ambitions if you want to move in pace with other people. You are an aspiring leader in the way you talk to people. I think your best strength is in ability to see into the future and carry on with different aspects of life. You managed to help our sick friend, study for your exams, help your parents with their business, and still have time for friends. But if you push too much, you might burn out. Your best strength is your organizational skills. You were able to organize our estate badminton team for your entire team. Your weakness is that sometimes you may fail to incorporate other peoples’ ideas in teamwork decisions. Loving and approachable- I think this is the strongest trait that I possess. My mantra in life is and has always been that â€Å"Love and compassion are my life statements, and which are the highest forms of intelligence.† This is why all my interactions in life are full of tenderness. I believe that every human being has feeling and emotions, and that a change in my mood can have great effects on, and probably spoil someone’s day. Moral compass- When my friends wrote that I have good organizational skills, most, if not all who mentioned this trait gave an explanation that I always try to justify my responses and actions in a manner that shows moral uprightness. Being a loving individual, I try to make people around me happy and comfortable. I tend to partake of only things that I consider permissible, and

Hitchens Rationality of Atheism Essay Example | Topics and Well Written Essays - 1250 words

Hitchens Rationality of Atheism - Essay Example And this puts the entire question of creation as proscribed by the religions a tall claim. Religion has been a major promoter of violence through out the world. Every one of the religions has fought their own 'crusades' for their own sacred places. How, he argues, is that there is difference between on location and the other on the surface of the earth He cites numerous examples where this has happened all over the world in the name of religions, be it Catholics, Hindus, Muslims or Jews. Similarly, the mad faiths people have on the religions have led them to take to unwanted assumptions and blind faiths. He quotes Heinrich Heine, 'In dark ages people are guided by religion, as in a pitch black night a blind man is the best guide; he knows the roads and the paths better than a man who can see. When daylight comes, however, it is foolish to use blind old men for guides'. Most of the religions, according to him, promise punishments for sexual expletives any person might involve in. If sex is abhorred why was it that God had to have it at all God who was the all powerful creator, could have easily redesigned the entire evolution if he did not want human race to indulge in something like that. According to him, the 'creators' of religions, man, have done it to their advantage and to subjugate half of the human population to their control. And most of the monotheistic religions, preach that human beings are sinners and that they need to supplicate to God every day as under a monarch. Faiths in religion, religious dogmas and in astrology are all badly placed. Aristotle pointed out that twins do not have the same future whereas as per astrology they should be having almost similar future. All these arguments are presented by the author in support of atheism. Section 2: Critique of Hitchen's God is not Great. Your perception and evaluation of Hitchen's argument seems to be on the wrong premise. Hitchen declares himself as anti-theist and not atheist to start with. Though the title talks of God, in his book he is not presenting himself as a person anti to God. Therefore, we need not look for evidence in the book for arguments anti to God. As an anti-theism person, he is opposing the practices of theism as we know it. Theism and the dogmas of theism are laid down millenniums back and to say that they fit into the current situation does not belong to the scientific thinking. I think the litmus test has been wrongly applied and the perception of the author has not been taken into consideration. Applying the rule 1, denial of what is known is irrational, we could easily see and the author establishes starting from a number of scientific principles how the religious dogmas have criticized and crucified people who stood up with new ideas. Whether it is that earth goes round the sun or that witch craft does not exist, the principles of the religious theism did not allow reconsideration of their thoughts. It denied the known facts of the case. There are number of cases where Hitchen substantiates, theism has denied known scientific facts. Theism fails in the first test itself. Theism fails in the second test too. Whether it is the crusades or the creation of Israel at the end of the Second World War, theism has only created death and destruction in the name of religion. The belief in what is preached by theism has not led the people to rational living is what is the argument of

The Knowledge gained from experience and education Research Paper

The Knowledge gained from experience and education - Research Paper Example A dissertation shows that an individual can work alone and helps in the individual’s career development while assessing the skills and competencies (White, 2003, p.3). All through my course work, I have learnt allot in the Human resources management; the role of human resources in competitive success, strategic human resource management and human resource planning, foundations of recruitment and selection and psychological perspectives of Human Resources Management, the foundations of performance management, managing compensation and rewards and the contemporary issues affecting human resources management. All these have enabled me have a greater understanding of Human resource management as a course. Each of these chapters and units have been accompanied and presented with a case study to better understand the concepts. Since the main function and goal of the Human resources management of any company is to supervise the employees, I will be able to help the company attain its goals by maximizing on the employees capability and at the same time motivating them. This friendly environment will make the company soar into greater heights. The Human Resources department of any company brings all the employees together to be able to act as a team to achieve the desired goals. I have learnt that for a company to boost the employee loyalty, their basic employment needs and requirements need to be met in time. Such basic needs include timely release of the pay checks, provision of health benefits and salary increase. I have also learnt that the Human resources department is concerned with the adherence to the corporate social responsibility (CRS) policies by showing the staff that they are highly appreciated and recognized. I will be able to conduct my research through intensive research methodology which will enable me acquire

Marketing Process Model by Robert J Dolan Dissertation

Marketing Process Model by Robert J Dolan - Dissertation Example Customer Acquisition 10 2.10. Customer Relation 10 2.11. Profits 11 3. Conclusion 11 References 13 Appendix 14 1. Introduction 1.1 Objective Current paper focuses on the examination of the various aspects of the Marketing Process Model, as developed by Robert Dolan in 1997. The effectiveness and the practical implications of the particular model are analyzed by referring to the literature that has been published in regard to the specific subject. 1.2 Methodology The literature related to the Marketing Process Model has been reviewed for identifying the elements and the role of the particular model. Effort has been made so that only academic journals are used, so that the credibility of findings is secured. 1.3 Limitations The value of marketing in enhancing business performance cannot be doubted. However, the choice of appropriate marketing strategy can be a challenging task for most marketers worldwide. Two are the key reasons for the above phenomenon: the continuous alteration of t he modern market and the lack of skills of individuals involved in the particular activities. The use of marketing models that have been widely used in the international market can help a firm to avoid failures, at least major ones, in regard to its marketing plans. From this point of view, the use of the Marketing Process Model could secure the growth of organizations operating in different sectors. However, not all aspects of the particular model have been carefully reviewed in the literature. Due to this fact, not all implications of the above model are known. This study could help to understand clearer the value of Marketing Process Model and to identify the model’s aspects that should be further studied. 2. Literature Review 2.1. Marketing Process: Initial Considerations Marketing process is a quite complex one. According to the literature published in this field, there are different approaches for promoting a product/ service in a particular market (Jaakkola et al. 2010 ). The Marketing Process Model, as suggested by Robert Dolan, can offer a series of advantages: a) it can employ a high range of methods/ approaches, increasing the chances for success, b) it is flexible and can be appropriately alternated for meeting the needs of the target market, c) it has been widely used in practice, a fact that increases its credibility (Jaakkola et al. 2010). The particular Model, also known as B2B model, can be effectively used in different sectors and under different market conditions (Jaakkola et al. 2010). 2.2. Strategic Marketing Strategic marketing is a term used in order to describe a series of activities that need to be developed in order for a particular product/ service to reach the target market successfully without failures, either in terms of cost or in terms of time (Kotler et al. 2009). The difference of strategic marketing, compared to the traditional marketing, is that the former is highly based on various theoretical models and different app roaches for achieving the target described above (Kotler et al. 2009). These approaches and theories are analyzed in the sections that follow. 2.3. Customers analysis 2.3.1. Needs In marketing, efforts have been made so that the Maslow Hierarchy of Needs theory is used. The particular model can ensure that consumer will be keep motivated in using a particular prod

HEALTH SCIENCES AND MEDICINE Coursework Example | Topics and Well Written Essays - 500 words

HEALTH SCIENCES AND MEDICINE - Coursework Example With shortage of nurses in the healthcare sector, it is evident that the safety and quality of healthcare is indeed compromised. Ideally, the shortage would overwhelm the already existing nurses, an aspect that causes distress and dissatisfaction among such nursing professions. Additionally, there is also the possibility of frustration among the professions, which contributes significantly to burnout on the job and the other different roles played by such individuals. The increased shortage really undermines the patient treatment outcomes considering the poor service delivery aspect (AACN, 2009). A number of causes can be attributed to the shortage of clinical nurse in healthcare centers and mostly in Hallways hospital. First, it is critical to state that shortage of clinical nurses in healthcare facilities is a problem that affects the entire globe, and, therefore, not limited to a particular region (Lavoie-Tremblay et. al., 2008). This ideally means that provision of healthcare services is an element of the healthcare system that is currently under threat. Insufficient supply of nurses to hospitals is indeed a stressor for a number of institutions Hallways hospital included. Despite the difficulty in estimating the exact effect attributed to such occurrences, the reasons for the cause are very obvious. Out of the numerous causes of shortage of clinical nurses in Hallways hospital, four are identified as the potential causes. These include the increased demand of nurses in the healthcare sector. In most instances, the number of individuals registering for nursing causes in the different colleges due to the fact that poor working conditions has been identified as the possible cause. Such an aspect can well be stated as demographic changes in the nursing workforce that decreased the supply of working clinical nurses (AACN, 2009). Another significant contributor towards the increased shortage

Business and Management Essay Example | Topics and Well Written Essays - 1500 words - 1

Business and Management - Essay Example Recently UK government tried to privatise the royal mail partially. According to Lord Peter Mandelson, the business secretary of the country, it is required to have a strategic partner for bringing a gale-force fresh air in the culture and management of the organisation (Tyler, February 3 2009). The main objective of privatising the organisation is to modernise it and improve its financial condition. UK government found that there is significant declination in royal mail’s popularity and demand as there is other advanced mode of communication like email has emerged. According to some analysts there is almost 7 billion euro pension deficit in Royal mail. UK government provide various attractive benefits to royal mail so it stays ahead in the competition. But according to experts the decision of making it modernise and atomise it by bringing a private sector company as the strategic partner might result to 40,000 to 50,000 job cut. As a consequence Communication Workers Union (C WU) asked the workers to go for a strike till the decision is reconsidered. The union claimed that over 12,000 postal employees would go for strike in different cities like London, Edinburgh, Plymouth and Bristol (Hope, July 15 2009). In UK postal industry this is worker’s strike is a historical problem which is actually badly affecting the future of UK postal industry. Proper understanding and implementation of strategic human resource management would be the ultimate solution for this type of situation. Strategic human resource management is such a complex process that is continuously evolving and being discussed and studied by academic experts. There is no proper definition of Strategic human resource management as different people have different opinion regarding the topic. According to Wright and McMahan SHRM is â€Å"The pattern of planned human resource deployments and activities intended to enable the forms

Business Ethics and Rules Essay Example for Free

Business Ethics and Rules Essay Personally, I agree that Solomons ethical fundamentals are a good moral foundation for a business. â€Å"Business ethics is the study of what constitutes right and wrong (or good and bad) human conduct in a business context. † (p25) From the lecture, we know that ethics matters because â€Å"how organizations behave have important implications for how they fulfill their social and economic roles† and â€Å"their success as well as the success of their employees, customers, etc. † Thus, running a business ethically is good for business. Applying Solomon’s three C’s of business ethics and the eight rules of thinking ethics in business make good sense. The three C’s of business ethics include compliance, contributions and consequences. The first C is â€Å"the need for compliance with the rules, including the laws of the land†¦and such general concerns as fairness. †(p36) As a saying goes, â€Å"Nothing can be accomplished without norms or standards. † Rules in business are intended to assert business structure or to control or influence the behavior of the business. Let’s take EU-Rent for example. EU-Rent is a car rental company owned by EU-Corporation. EU-Rent sets up rules about rentals, returns, servicing and customers. For example, â€Å"EU-Rent keeps records of customers, their rentals, and bad experiences. This information is used to decide whether to approve a rental. † If EU-Rent doesn’t comply with these rules, it may not organize well. The second C is â€Å"the contributions business can make to society, through the values and quality of one’s products or services†¦and usefulness of one’s activities to the surrounding community. † (p36) For instance, economists conventionally assume that organization’s primary goal is to maximize profits. Many successful organizations are gradually aware of the important relationship between profits and contributions to society. Starbucks has seen its profits rise as it has increased its investment in social issues. Those organizations who are making profits and don’t contribute to society may receive criticism from the public. As the article â€Å"The Sichuan Earthquake and the Changing Landscape of CSR in China†, which was written by Ariel McGinnis, James Pellegrin, Yin Shum, Jason Teo, and Judy Wu (University of Pennsylvania), mentioned, â€Å" In the days and weeks following the Sichuan earthquake, many multinational corporations(MNCs) pursued a global CSR (corporate social responsibility) policy in line with their international standard. While some multinationals pledged cash, many others pledged a combination of cash, equipment and services. Domestic firms, by all accounts, out-donated multinationals†¦The popular perception was that international firms relief contributions not only did not match those of local Chinese companies in terms of scale or timeliness, but also were not commensurate with their presence in the Chinese market. Chinese consumers quickly seized upon this disparity by openly attacking major MNCs, calling for a boycott of their products †¦ The Chinese public soon gave these affected MNCs the nickname of ‘international iron roosters. The term refers to a bird that never gives up a single feather, and its usage highlights the perceived stinginess of these international firms†¦Despite their additional donations,’ iron-rooster’ MNCs continued to face angry consumers throughout China, resulting in severe public backlash, including protests at several McDonalds and blo ckades at KFCs throughout Sichuan province and the rest of China. † From this example, we can see how important the contributions that organizations should make to the society are. The third C is â€Å"the consequence of business activity†¦including the reputation of one’s own company and industry†¦Ã¢â‚¬  (p36) Why the consequences of business activity are so important? Let’s have a look at the following example. Once, Sanlu was one of the oldest and most popular brands of infant formula in China. It went into bankruptcy after the â€Å"Sanlu milk scandal†. Based on the media, â€Å"By November 2008 China reported an estimated 300,000 victims, six infants dying from kidney stones and other kidney damage, and a further 860 babies hospitalized. Since the Sanlu Group didn’t solve the problem and recall the products in time, it leaded to a horrible incident. Doubtlessly, what did organizations do may affect their development and even the well-being of the public. Organizations should not blindly pursue for profits only but also be responsive to society. To become successful, a business needs to be driven by strong ethical va lues. If a corporation fails to adopt ethical values and cannot be responsive to society, it will fail, just like the Sanlu Group. Besides the three C’s of business ethics, Solomon also stated the eight rules of thinking ethics in business, which are also good moral foundations for a business. The eight rules include â€Å"consider other people’s well-being, including the well-being of nonparticipants; think as a member of the business community and not as an isolated individual; obey, but do not depend solely on, the law; think of yourself—and your company—as part of society; obey moral rules; think objectively; ask the question ‘What sort of person would do such a thing? and respect the customs of others, but not at the expense of your own ethics. †(p40, 41) Based on the above statements, it is obvious to see that they are mainly about the concept of three C’s. According to the text, thinking ethically means â€Å"thinking in terms of compliance with the rules, implicit as well as explicit, thinking in terms of the contributions one can make as well as oneâ€⠄¢s own possible gains, thinking in terms of avoiding harmful consequences to others as well as to oneself. (p40) In the case of â€Å"Sanlu milk scandal†, one of the main reasons behind

Departmental imaging requirements Essay Example for Free

Departmental imaging requirements Essay Introduction Diagnosing, staging, and re-staging of cancer, as well as the monitoring and planning of cancer treatment, has traditionally relied on anatomic imaging like computed tomography (CT) and magnetic resonance imaging (MRI). Spatially accurate medical imaging is an essential tool in three dimensional conformal radiation therapy (3DCRT) and intensity-modulated radiation therapy (IMRT) treatment planning. CT imaging is the standard imaging modality for image based radiation treatment planning (RTP). CT images provide anatomical information on the size and location of tumors in the body. They also provide electron density information for heterogeneity-based patient dose calculation. The major limitation of the CT imaging process is soft tissue contrast, which is overcome by using contrast agents or using another anatomical imaging modality like MRI. One of the disadvantages of anatomical imaging techniques like CT and MRI is its inability to characterize the tumor. Tumors need to be characterized whether they are benign or malignant and if malignant it would be helpful to know whether the proliferation is slow or fast. Necrotic, scar, and inflammatory tissue often cannot be differentiated from malignancy based on anatomic imaging alone. Anatomical imaging has high sensitivity for detection of structural changes, but a low specificity for further characterization of these abnormalities. Single photon emission computed tomography and positron emission tomography (PET) are imaging techniques that provide information on physiology rather than anatomy. These modalities have been used for evaluation of tumor metabolism, differentiation between tumor reoccurrence and radiation necrosis, detection of hypoxic areas of the tumor, and other functional imaging. Radiation treatment planning requires an accurate location of the tumor and the normal tissue and also knowledge of the size of the tumor for contouring the treatment volume. Although PET provides necessary functional information for RTP, it has a few limitations. The spatial resolution of PET is too poor to give accurate quantitative information. The greatest limitation in using PET for RTP is its lack of anatomical information. This limitation of PET is overcome by evaluating PET and CT images together. Fused PET and CT images give better diagnostic evaluation than PET or CT images used alone (Bar-Shalom et al, 2003; Cohade Wahl, 2003). But fusion of PET and CT images are meaningful only when they are correctly spatially registered. Hence a proper spatial registration is required for accurate delineation of tumor volume. The necessity of accurate spatial registration of fused images requires different fusion techniques for different image datasets. Software fusion and hardware fusion are the two different approaches considered by the scientific community (Townsend et al, 2003; Townsend et al, 2002). Software fusion approaches use different transformation algorithms to fuse different modality images acquired at different times. The transformation algorithms are classified as rigid and non-rigid transformation algorithms. They are based on whether they fuse images of rigid-body (e. g. , head) or non rigid (e. g. , abdomen) objects (Patton, 2001; Yap, 2002). Although software fusion gives better diagnostic information than using separate images, physicians may not rely on the information if the fused images were acquired at different times. Also the chances of a change in patient position are high for image acquisition done at different times. The hardware approach of image fusion is headed towards designing a single imaging system to acquire simultaneously the different image modalities required. Hardware fusion is partially achieved by construction of a hybrid PET/CT scanner (Beyer et al, 2000; Townsend et al, 2004) which acquires different modalities sequentially. These hybrid scanners are two separate scanners enabled to operate in sequence one after another to acquire the different image modality datasets in a single imaging session. Although hybrid scanners do not give a true hardware fusion and have not proven to be a better fusion technique scientifically (Kalabbers et al, 2002), they have gained popularity for image acquisition in a single session. Due to reduced scan time and patient motion, PET/CT is considered reliable among the oncology community. These hybrid PET/CT scanners, due to reduced scan time and reliable registration of PET and CT datasets, are becoming common in RTP. A PET image fused with a CT image can be used in treatment planning to eliminate geographic misses of the tumor and escalation of dose to the hypermetabolic aspects of a tumor. Fused images improve the accuracy in staging of lymph nodes. Although the use of PET/CT in RTP is growing at a fast pace, little research has been done in the direction of validating the PET/CT datasets for RTP. Discussion CT images describe the electronic density distribution of cross sections of the patient anatomy. CT systems provide gray scale display of linear attenuation coefficients that closely relate to the density of the tissue. CT imaging evolved from conventional planar radiographs. In planar X-ray film imaging the three dimensional anatomy of the patient is reduced to a two dimensional attenuation projection image and the depth information of the structures are lost. In CT imaging several attenuation projection images for a volume of tissue are acquired at different angles. These sets of projection images are reconstructed by filtered back projection algorithm to generate two dimensional attenuation cross-section of anatomy of the patient. The attenuation measurement for a CT detector element is given by Equation 1 and Equation 2. Equation 1 represents attenuation measurement for homogenous object and Equation 2 represent attenuation measurement for inhomogeneous (heterogeneous) objects. _ P(x) =1n [I0] = ? x ? (1) __ _ I x _ _ _ P(x) = 1n [I0] = x d x ? (2) __ L _ I x In the above equation P(x) is the measured projection data for attenuation along the x direction. Io is the intensity of the x-ray beam measured without the patient in the way for that detector element. This is also known as a blank scan. I (x) is the measured intensity after attenuation by the patient.? (x) is the measured attenuation coefficient as a function of location in the patient. A CT scanner positions a rotating x-ray tube and detector on opposite sides of the patient to acquire projection images. Early CT scanners used pencil beams of x-rays and a combination of translation and rotation motion to acquire projection images (Bushberg et al, 1994). Modern CT scanners have a stationary or rotating detector array with a rotating fan beam x-ray tube. There are also two types of scanning: axial and helical CT scanning. In axial scanning the patient is moved step by step acquiring sets of projection images for each slice. In helical scanning the patient table moves continuously while the x-ray tube acquires a series of projection images. The projection images are acquired for a helical path around the patient. In helical scanning to reconstruct a cross-sectional planar image, the helical data is interpolated to give axial plane projection data before reconstruction. By removing the time to index the table between slices the total scan time of the patient is reduced. Also reconstruction can be done for any slice thickness after acquiring the data. This helical scanning is available in most of the current CT scanners. The reconstructed CT image is a two dimensional matrix of numbers, with each pixel corresponding to a spatial location in the image and in the patient. Usually the matrix is 512 pixels wide and 512 pixels tall covering a 50 cm x 50 cm field of view. The numeric value in each pixel represents the attenuation coefficient as a gray level in the CT image. These numbers are called Hounsfield units or CT numbers. The reconstruction process generates a matrix of Hounsfield units which give the linear attenuation values normalized to the attenuation of water. This normalization is given by Equation 3. CT Number (HU) = 1000 (? pixel ? water) ____________ ?water CT number gives an indication of the type of tissue. Water has a CT number of zero. Negative CT numbers are typical for air spaces, lung tissues and fatty tissue. Values of ? pixel greater than ? water correspond to other soft tissues and bone. Radiologists occasionally make critical diagnostic decisions based on CT number of particular regions of interest. Also attenuation values given by CT numbers are used to calculate the dose delivered to the tumor in RTP. CT number is an important parameter in CT images which must be frequently checked for accuracy. Positron emission tomography (PET) imaging generates images that depict the distribution of positron emitting radionuclide in the patient body. PET imaging often uses the F-18 fluorodeoxyglucose (FDG) radioactive tracer to track increased glucose metabolic activity of tumor cells and to provide images of the whole body distribution of FDG. When the positron is emitted by the radioactive tracer it annihilates with an electron to generate two 511 kev photons emitted in nearly opposite directions. These photons interact with the ring of detector elements surrounding the patient. If both the emitted photons are detected then the point of annihilation lies on the line joining the points of detection. This line joining the points of detection is known as the line of response (LOR). The circuit used by the scanner to record the detector interactions occurring at the same time is called coincidence circuitry. This whole process is called annihilation coincidence detection. Thus a PET scanner uses annihilation coincidence detection instead of mechanical collimation like gamma cameras to acquire projections of activity distribution in the patient. Projections acquired at different angles are reconstructed using iterative algorithms to generate cross-sectional images of activity distribution. The annihilation coincidence detection process allows many false events to be acquired. Corrections are necessary for these false events before the projections are reconstructed. The total events acquired are classified as trues, random and scatter. A true coincidence is simultaneous interactions occurring in the detectors resulting from emissions occurring in the same nuclear transformation. Random coincidences occur when emissions from different nuclear transformations interact in coincidence with the surrounding detectors. Scatter coincidence occurs when one or both photons from annihilation is scattered in the patient body and interact with the detector to give a false LOR. The acquired annihilation events need to be corrected for random and scatter events. Random coincidence events along any LOR may be directly measured using the delayed coincidence method (Levin, 2003). The delayed coincidence method uses two coincidence circuits. The first circuit measures both true and random coincidence events. The second circuit has a delay of several hundred microseconds inserted into the coincidence window, so all true coincidences are thrown out of coincidence. The counts measured in the second circuit are subtracted from the first to give true counts. Scatter correction is done for the projection data by model-based scatter estimation (Levin, 2003). The scatter correction factor is estimated by mathematical models and applied to the projection data before reconstruction. Image fusion was initially achieved by software fusion of anatomical and functional images. Software fusion was generally successful with brain and rigid body volumes. It encountered significant difficulties when fusing images of the rest of the body. Alignment algorithms fail to converge the two image sets due to problems of patient movement or discrepancies in patient positioning between two scans. Also involuntary movements of internal organs arise when patient are imaged on different scanners and at different times. Dual modality PET/CT imaging is a combination of imaging technologies helping to acquire accurately aligned anatomical and functional images in the same scanning session. Also an additional advantage of the combined PET/CT scanner is the use of CT images for attenuation correction. CT images can be scaled in energy and used to correct the PET data for attenuation effects (Kinahan et al, 2003; Kinahan et al, 1998). Dual-modality PET/CT was first built at the University of Pittsburgh in collaboration with CTI (Knoxville, TN) and Siemens Medical Solutions (Hoffman Estates, IL), combining separate PET and CT scanning devices into one device. The PET/CT prototype consisted of a rotating partial ring PET system and a single slice CT scanner mounted on the same rotating support. The CT scanner combined with PET often uses helical scanning CT to enable fast patient throughput, but new scanners with both helical and axial scanning are available now. The CT data is usually acquired first, followed by PET acquisition. There are typically two separate acquisition processing units for CT and PET, and an integrated display workstation. The acquired CT and PET datasets are sending to the reconstruction processing unit for reconstruction. Reconstructed images are fused in the fusion workstation. CT and PET images can also be separately viewed in the workstation. The protocol for PET/CT imaging starts with patient preparation. 5 – 15 mCi of FDG is injected into the patient 45 – 60 min before the start of image acquisition. After 45 min, the glucose circulates through the body; the patient gets ready for image acquisition by emptying the bladder. The patient is positioned on the table for an initial topogram. The topogram is used to select the scan range for PET/CT image acquisition. The scan range is selected as a number of bed positions. Once the image acquisition region is selected in the topogram, the helical CT scan is done first; it takes around 30 sec to acquire one bed position. After completion of the CT portion, the scanner bed is moved to the PET starting position and the emission scan is started. The emission scan duration per bed position varies with the detector technology used. With conventional bismuth germinate oxyorthosilicate (BGO) system, acquisition times will range from 5 to 8 minutes per bed position. The new lutetium oxyorthosilicate (LSO) technology reduces emission scans to 3 to 5 minutes per bed position (Humm et al, 2003). The CT data are used to perform attenuation correction. Image reconstruction is completed a few minutes after the PET image acquisition is completed. Since the CT data is used for attenuation correction, the total scan duration for a PET/CT scanner is shorter than that for stand-alone PET scanner, because the CT acquisition is much faster than a conventional PET transmission acquisition. Conclusion. To conclude, Positron Emission Tomography/Computerized Tomography (PET/CT) is an imaging test that produces high resolution pictures of the body’s biological functions and anatomic structures. These images show body metabolism and other functions rather than simply the gross anatomy and structure revealed by a standard CT or MRI scan. This is important because functional changes are often present before obvious structural changes in tissues are evident. PET/CT imaging can uncover abnormalities that might otherwise go undetected. 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