Helical CT Scan in Comparison to MRI Scans

Helical CT Scan in Comparison to MRI Scans Introduction Helical CT is also known as spiral CT; the two terms are interchangeable (Kalender, 1994). Both MRI and helical CT have been introduced into clinical practice ahead of any evidence for cost-effective improvement in clinical care. Both technologies are still evolving. For instance vascular 3D imaging is a newly expanding indication within CT. Although helical CT is replacing conventional CT the question arises as to whether it will replace MRI. 1) Equipment Helical CT began in the 1990’s. It is a fast technique; data is collected continuously at less than one second for a 10 mm slice. It is called helical because the patient moves continuously though the machine whilst the X-ray tube rotates around them. Slip ring technology enables the scanner, mounted on a gantry, to continue rotating in the same direction around the patient yet still maintain its power supply and x-Ray capability. Because it is so quick breathing does not affect the quality of the final image and it is an excellent way to view the lungs and liver. Because of the continuous rotation helical CT enables patient translation and the acquisition of data to take place at the same time. Helical CT requires completely different equipment to convention CT necessitating the replacement of the entire unit not just an upgrade. A multislice CT scanner is along the same principle as a helical scanner but is even faster still and contains more detection elements. Although the actual data acquisition is so much faster with multislice the time required to process the image is lengthy (so patient through put will be no faster). The amount of data storage space required for multislice images is incredibly vast and may overload the capability of the existing PACS system within the hospital. The equipment for MRI consists of a large, heavy magnet which creates the magnetic field. Magnetic shielding of the room is necessary together with stringent safety precautions to avoid accidents for instance with flying metal objects within the room. The scanning tube where the patient must lie is relatively enclosed and this can create problems with claustrophobia. The equipment is also very noisy which may unnerve the patient. MRI requires more extensive software for viewing the images than does CT. Some MRI machinery is more open permitting greater patient access even to the extent of allowing simultaneous surgery (Gould and Darzi, 1997). 2) Techniques MRI involves the person being placed in a large magnet the magnetic field of which causes all the protons (the nuclei of hydrogen atoms) in the body to line up and oscillate at a certain frequency (precision frequency). Radiofrequency pulses are emitted from the machinery at the same frequency as the precision frequency causing the protons to come out of alignment for a brief time and subsequently realign emitting energy in the process. The radiofrequency of these emissions is specific to the type of issue (since it reflects the hydrogen content) and is then computed to form an image. Patient movement is a major problem with the MRI technique since data acquisition is quite slow and so it is not as good as helical CT for moving organs such as the lungs and liver. MRI scans are more expensive to produce that helical CT. The major advantages of MRI over helical CT are that MRI involves no x-Ray exposure and certain structures provide better images with MRI such as the brain and musculo skeletal system. MRI is definitely the best test for acoustic neuroma (Renowden and Anslow 1993). CT is better than MRI for imaging brain trauma and is better in the abdomen for the bowel (on account of it being a moving structure) whereas MRI is better in the pelvis. Helical CT is finding a place in the diagnosis of pulmonary embolism (Roy 2005). The disadvantages of CT are the x-Ray dose and the nephrotoxicity of some contrast agents. In 1993 the Royal College of Radiologist guidelines recommended MRI be used for investigations on the brain, musculoskeletal system, oncology and paediatrics, the 1995 version of the guidelines recommended back pain beyond six weeks be investigated by MRI. The Royal College of Radiologists document on oncology (1999) provides graded evidence based recommendation of which scanning modality to use according to tumour site. 3) Staff Staff training is necessary for both modalities of scanning. MRI staffing costs are higher than with CT. Because MRI scans are in such demand and scanning time long it is often necessary to run the machines in the evenings and at weekends (Moore Golding, 1992). Multislice CT can involve increased radiologist workload. 4) Patient Patients with metal implants or pacemakers or who are claustrophobic are unsuitable for MRI. Mechanical ventilation is a relative contraindication. Patients with acute major trauma including head injury are unlikely to be suitable for MRI because of the duration of scanning. The increased x-Ray dose to patients (and to the community) of the later generation CT scanners is of concern (National Radiological Protection Board, 1990). For this reason MRI is the preferred modality for children and fetuses (Duncan 1996). Patients requiring interventional procedures may be suitable for a CT fluoroscopy (Wagner 2001). 5) Quality of results MRI is preferred for the brain and spine (where it is of overriding advantage), orthopaedics and the pelvis. MRI produces very accurate images of soft tissues but imaging time is longer and artefacts are caused by patient movement. It is likely it has reduced the number of knee arthroscopies (Stoner, 1995) and it is anticipated to reduce the number of invasive radiological investigations such as angiograms. MRI may develop a clinical role as investigating the actual function of the brain in neuropsychiatry (Callicott and Weinberger1999). CT is preferable for bone. In brain trauma, subarachnoid haemorrhage and acute cerebrovascular disease MRI is not as good as CT. Spiral CT is used for the lungs and abdomen and pelvis. It is valuable in detecting small lesions. It is helpful in trauma patients since the procedure is so quick. Spiral CT does lose a bit of resolution as compared with conventional CT and so for structures that are not moving conventional CT or MRI has the advantage. 6) Cost Cost considerations include those of initial purchase (or lease) set up and also running costs. Assistance in the procurement process is available from the Diagnostic Medical Equipment team which is working closely with the Department of Health in the optimising of value for money in the replacement of all MRI and CT scanners that are pre-1997. A 16 multislice CT scanner costs approximately  £500 000 whereas an MRI scanner is more at  £800 000; running costs are also more with MRI (Frank, 2003). Bowens and Smith (writing in 1999) state the costs of an MRI scanner are from  £400 000 for a 0.5T and  £750 000 for a 1.5T. They state the service contracts are around  £50 000 per year and that to lease a machine costs about  £120 000 per year. MRI may be more expensive to install since the magnet is large and heavy. The site may be unsuitable with regard to load bearing or access. In any case expense will be incurred in magnetic shielding. MRI is a relatively expensive imaging modality. Fletcher (1999) has analysed costs of acquiring and operating MRI in the NHS over a seven-year machine lifespan. Its staffing, upgrade, maintenance and running costs are all high. The cost of an MRI scan varies from  £30 to  £180 (Bowens and Smith, 1999). In evaluating costs it is necessary to look at the whole picture. The running costs of isolated MRI machines will be higher than where machines are grouped together. Smaller MRI scanners just for joint scanning use may prove cost effective (Marti-Bonmati Kormano, 1997). If a more expensive scanning modality saves on the costs of surgery then overall there may be economic gain. For instance MRI may avoid knee joint surgery (Bui-Mansfield 1997). It is important to ensure that it is actually replacing other investigations or surgery and not just adding to them (Hailey Marshall, 1995). Overall the cost effectiveness will depend on how appropriately the imaging modality is used. Regarding CT the X- Ray tubes are expensive. A helical scanner is likely to need one x-Ray tube replacement per year (possibly more frequently in the case of a multislice scanner) and this will cost approximately  £30000-40000 (Conall and Hanlon, 2002). Berry (1999) performed a systematic review finding little clinical or economic impact of spiral CT. Conclusion Although there has been away from MRI to helical CT in some clinical situations units will need access to both types of scan. Cooperation between different units is important in order to provide a comprehensive service to the population. It is likely that some patients such as orthopaedic outpatients should move to another unit for the scan. Computerised reporting makes off site scanning realistically closer. Choice of scanning modality is likely to ultimately depend upon collaboration with local units to develop a hub and spoke approach to providing cost effective services which are also effective and convenient for patients. References Book Fishman EK Jeffrey RB Spiral CT. Principles, Techniques and Clinical Applications. 2nd edition. 1998 Philadelphia. Lippincourt Raven. Articles Berry E et al A systematic literature review of spiral and electron beam computed tomography: with particular reference to clinical applications in hepatic lesions, pulmonary embolus and coronary artery disease. Health Technology Assessment, 1999; 3(18) Bui-Mansfield LT et al Potential cost savings of MR imaging obtained before arthroscopy of the knee: evaluation of 50 consecutive patients. American Journal of Roentgenology 1997; 168: 913-18 Callicott JH and Weinberger DR Neuropsychiatric dynamics: the study of mental illness using functional magnetic resonance imaging. European Journal of Radiology, 1999: 30(2): 95-104 Conall JGarvey CJ and Hanlon R Computed tomography in clinical practice BMJ 2002;324:1077-1080 Fletcher J et al The cost of MRI: changes in costs 1989-1996. British Journal of Radiology 1999; 72(5): 432-437 Duncan KR. The development of magnetic resonance imaging in obstetrics. British Journal of Hospital Medicine, 1996; 55(4): 178-81 Frank J introduction to imaging Student BMJ 2003;11:393-436 Gould SW and Darzi A The interventional magnetic resonance unit the minimal access operating theatre of the future? British Journal of Radiology 1997; 70 (Special issue): S89-97 Kalender WA Spiral or helical CT; right or wrong?[letter] Radiology 1994; 193:583. Hailey D and Marshall D The place of magnetic resonance imaging in health care. Health Policy, 1995; 31: 43-52 Marti-Bonmati L Kormano M. MR equipment acquisition strategies: low-field or high-field scanners. European Radiology 1997; 7(Supplement 5): 263-68 Moore NR and Golding SJ Increasing patient throughput in magnetic resonance imaging: a practical approach. British Journal of Radiology, 1992; 470-75 26 National Radiological Protection Board. Patient dose reduction in diagnostic radiology. Didcot, 1990:1(3). Renowden SA and Anslow P. The effective use of magnetic resonance imaging in the diagnosis of acoustic neuromas. Clinical Radiology 1993; 48(1): 25-8 Roy P-M Colombet I and Durieux P et al Systematic review and meta-analysis of strategies for the diagnosis of suspected pulmonary embolism. BMJ2005;331:259 Royal College of Radiologists. A guide to the practical use of MRI in oncology. London RCR, 1999b Royal College of Radiologists. Making the best use of a department of clinical radiology: guidelines for doctors (2nd edition). London RCR, (3rd edition) 1993, (4th edition) 1998, (5th edition) 2003. Stoner DW. The knee. In: Seminars in Roentgenology 1995; 30: 277-93 Wagner LK. CT fluoroscopy: another advancement with additional challenges in radiation management. Radiology 2001; 216: 9-10 Reports Bowens A Smith I Magnetic resonance imaging: current provision and future demands. Nuffield Portfolio programme Report No3. Northern and Yorkshire RD Portfolio programme at the Nuffield Institute for Health. December 1999. Available at http://www.nuffield.leeds.ac.uk/downloads/portfolio/mri.pdf Royal College of radiologists Making the Best Use of a Department of Clinical Radiology Guidelines for Doctors. Fifth Edition 2003 BFCR(03)3 Making the Best Use of a Department of Clinical Radiology Guidelines for Doctors. Fifth Edition Websites British Association of MR Radiographers http://www.bamrr.net/ Department of Health www.dh.gov.uk Diagnostic Medical Equipment team http://www.pasa.doh.gov.uk/dme/radiology/mr.stm

History of H&M Essay

H & M, (Hennes & Mauritz AB) is a Swedish multinational retail-clothing company, known for its trendy fashion clothing for men, women, teenagers and children. It started out as a single womenswear store in 1947, and subsequently transformed to a global company offering fashion for the whole family, and their home. The business concept is to give the customer unbeatable value by offering fashion and quality at the best price. H&M ensures the best price by having few middlemen, having a broad, in-depth knowledge of design, fashion, textiles, buying the right products from the right markets, and being cost-conscious at every stage. H&M is driven by seven core values, namely; Keep it simple, Straight forward and open-minded, Constant improvement, Entrepreneurial spirit, Cost conscious, Team work, Belief in people. H&M’s quality testing is extensive, coupled with hard work to make sure goods are produced with least possible environmental impact and under good working conditions. Production is outsourced to independent suppliers as H&M does not own any factories. Apart from this, H&M does not own any of its stores, as they rent store space from international and local landlords. H&M is present in 43 countries and has employed about 94,000 people as of 2011. It has 2,325 stores at end of 2011 and 2,629 stores at end of August 2012. It is ranked the second largest global clothing retailer behind Zara and No. 1 user of organic cotton worldwide. Current Logistics process of H&M H&M does not own any factory, they have outsourced to external suppliers that managed two departments: Procurement and Production. The Procurement function focuses on customers, fashion and composition of the range. The clothing designs are created in Sweden by around 100 internal designers, 50 pattern designers and an estimated 100 buyers. H&M’s method of production is customer-driven. The company puts emphasis into research and forecasting of emerging trends, both through traditional research methods and innovative ones such as street trends. This activity is conducted by central staff and national offices which are responsible for detecting new trends. The production function involves 21 production offices. H&M purchases garments from about 750 suppliers, in which 60% of production takes place in Asia and the rest mainly in Europe. The production offices have a mediating function between the internal buying department and external suppliers. They ensure that the buyers’ orders are sent to the right supplier, the goods produced are of the correct price and quality and that the suppliers adhere to the company’s code of conduct. Additionally, production offices also deal with the checking and testing of sample garments, which contributes to reducing lead times. The decision of determining which supplier is the right one is not only a matter of cost-efficiency but is dependent on other factors such as transport times, import quotas and quality control aspects. To reduce risk, buying is carried out on an ongoing basis throughout the year. Continuous IT developments over the years have helped to support H&M logistics. While the inventory management is primarily handled within the H&M organisation, transport is outsourced to third parties. In terms of distribution, H&M adopts sea transportation where their finished products are shipped to a distribution centre in Germany, which will serve as a transit terminal. The transit terminal will be en-routed to receive the goods from all the suppliers across the world. Upon arrival at the designated location, goods are inspected and allocated either in a store or in the centralised warehouse. The role of the warehouse is to hold and replenish inventory levels in stores according to selling trends.

Haier Performance management Essay

1.What are the specific practices of Haier’s performance management system? What are the guiding principles behind those practices? Haier, being the world’s sixth largest maker of large kitchen appliances, had 4% global market share and strong positions in the production of washing machine and refrigerators. The key success behind was Zhang, the CEO who brought the company fortunes. Several innovative human resource management practices were introduced. First, there was a set of colored footprints on factory floor. Any employee who has not performed well has to stand up on the yellow footprint and tell the employee why they have not performed well and how they will improve their performance. The employee who has performed best has to stand up on the red foot and explain why he had done a good job. One more tool used by the company to measure the performance of the employees on daily basis was to discuss with their supervisor and set clear goals of the employees before beginning of their shift. At the end of the day, they met again for assessment. Then, the employee would receive a colored face in a board s howing an informal grade for the day. For managers, their performances were reviewed weekly and the results were openly displayed at the cafeteria. Another tool used by Haier was the performance appraisal system the top 10% were promoted and bottom 10% were sent back to the training at the expense of the company. After this training if they again come under the bottom 10% then they were again given leave and this time they went to training but on their own expense. In the third review if they again come in to the bottom 10% then they were fired. Moreover, all the employees were treated as separate company and they have their different accounts and profit and loss statement. If the employees exceeded their goals then they increase savings in their accounts and when they did not reach their goals then they have debt on their account. This system was mainly designed to increase employee motivation to perform better than the standards defined. Talent pool was generated for any new opening in the company so that the best employee gets the new position. Job rotation was prevalent in the company and any employee was tested at different positions before assigning a final job. Evaluation was done by points system and any employee could be transferred out of the talent on not getting the points for minimum standards. The guiding principles behind those practices were  OEC (Overall, Every, Control and Clearance), 80:20 principle and Racetrack Model. Tha t’s mean, all performance dimensions of everyone everyday had to be considered and there were self-assessments and meetings with supervisors.  Also, Haier have their own 80:20 principle in which the 20% of the employees who were managers are responsible for the other 80% of the employees. If the employees did not perform according to the standards then their supervisors were liable for the results. Last but not least, under racetrack, the excellent employees had to keep racing and improving, creating a sense of competition. 2.Why does Haier’s performance management system work? What are the potential pitfalls of Haier’s system? Haier’s management was work and has been well received by workers as this could be reflected by the company’s success in the past 2 decades. With the new HR practices, the workers were given opportunities to display their motivation, innovative and competitive attitudes and capabilities of such kinds under Haier’s management. Also, all practices were carried put under great transparency, fairness and justice. Importance of â€Å"face† was a characteristic of Chinese cultural tradition. With the daily assessment and ranking, the sense of competition instantly increases. The results of the evaluation of workers were shown with individual names. It seemed that workers or managers of poor results would lose their faces. So the workers were motivated to do better.  The performance appraisal system the top 10% were promoted and bottom 10% were sent back to the training provided chances for the employee to improve and offer training before really fire them. Thi s was considerate and lenient. Also, the meeting with supervisors made the expectations and standards of works crystal clear. They set up, achieve and were accountable for the targets. Their performances were closely monitored, evaluated and rewarded and that’s why they were motivated. Moreover, under the 80:20 principle, the mangers had to have the courage and conscientiousness to assume responsibility at Haier. Thus, they had to be more dedicated and care more, leading to great effort and productivity for both the managers and workers. However, Haier’s management is in contrast to the old management of socialism. So there are maybe some potential pitfalls. â€Å"Face† and human relation are the two deep-rooted traditional Chinese concepts. If the Chinese employee cannot accept or adapt to the new practices, it arouse resentment among the employees. In long run, working under keen competition  may impose heavy burden to the employees, leading to stress and mental problems. A disadvantage in the footprint method is that it did not give any ranking to the employees so it would be diffi cult for decisions related to appraisals and salary increments. Sometimes, it might embarrass the employee as well. Haier ranked top 10% and bottom 10% of the employees. This could be morale.  The greatest challenge of this method is to differentiate between other 80% of the employees and this method may be biased by the recent performance of the employees. 3.If Haier expands into the U.S., will its performance management system be effective in the U.S.? Why or why not? If there is any change you would like to make, what would it be? It may not be that effective in the U.S. The U.S. culture is different from Chinese. They have low power distance and privacy is an important issue. The U.S. employees may feel being insulted if their performances are publicized, i.e. the colored footprint may not work. Also, there is higher level of performance orientation in U.S., emphasis is not put on daily performance but final result. They also enjoyed individualism and freedom so they may not like being instructed or guided too much by the supervisor every day so grievances will appear. To be more effective and acceptable, company can adopt different methods. One of them can be Graphic Rating Scale method which is the simplest and most popular method for the performance appraisal. In this method the employees are ranked on different scales such as communication, team work and skills related to their job profile. To eliminate the bias in the appraisal different ty pes of methods should be used and employees should be rated by different individuals. Rating can be done by their supervisor, peers and subordinates. Self-rating method can also be used.

From Vergil s Georgics, Book I ( Trans - 1715 Words

2. From Vergil’s Georgics, book I (trans. A.S. Kline 2001) The Georgics is a poem in four books by Latin poet Virgil. The subject of the poem is agriculture; but rather than be about idyllic rural life, there is tension and difficulty. The title is a fitting one, as it is derived from the Greek word georgika, which means â€Å"agriculture† (Perseus Project). The poem is on the subject of early man living off the land, only to have Jupiter (The Roman name for Zeus) add considerably more difficulties in rural life which in turn forces man to adapt or die. The reason for this being is that man must develop skills to survive the harsh wilderness in order to become worthy inhabitants of the land the gods gave them. Essentially, it is survival of the fittest. The poem is crafted with deliberate tension. Of chief importance is the contribution of labour to the success or failure of mankind’s endeavors, agricultural or otherwise. The poem is didactic, and is composed in hexameters, additionally the poem is modeled in a similar manner to Hesiod’s Works and Days. Hesiod’s poem shares similar themes to Georgics, it emphasizes man’s relationship with the land they live on and the importance of hard work to ensure survival. Both poems are didactic, which is a way of writing that emphasizes instructional and informative qualities. This comes as unsurprising as both writers promote labour and emphasizes its importance for achieving a comfortable life. There