​​​ Plewes and Kucharczyk (2012) gave T1 and T2 relaxation times of gray matter (GM), water matter (WM) and cerebrospinal fluid (CSF) in Table 2 of their publication. Figures 1 and 2 show the definition of T1 and T2 relaxation times. Fig 1. A typical T1 relaxation curve Fig 2. A typical T2 relaxation curve Instructions 1. Go to Bb and download an excel file titled 'Assignment 1' 2. Open the file, you will find a figure of T1 relaxation curves of GM, WM and CSF. The figure was plot using the above-mentioned sources. 3. Use the excel file to work out answers the following questions. You are expected to plot new data in the figure. 4. You are required to show and explain the steps, by using graphs, to find the answers. Question 1 (50%): TR=700msec and TE= 20msec are used to generated a T1-weighted images. How much is the signal differences between GM and WM? Question 2 (50%): TR=1500msec is used to generate a PD-weighted images. What is the best TE should be applied to ensure no contrast of GM and WM due to their T1 relaxation?Assignment 2 Question 1 (60%) Draw a comprehensive and detailed spin echo pulse sequence diagram with TR=500ms and TE=60ms. You are required to define the symbols and abbreviations use in the diagram. Calculate the shortest acquisition time required for a 2D 256X256 pixel image. You are expected to show and explain steps to get the answer. Question 2 (40%) In order to shorten the scan time, what is the maximum number of echo train length can be employed? What is the new scan time? Please show and explain steps to get the answer.Assignment 3 Part 1 (30%) Background Last year, a student was asked to write a literature review on 'Differences in image quality between 3T and 1.5T MRI scanners'. Below is one of the sections of his assignment, probably talking on MR signal generation. Unfortunately, the section was full of mistakes. You are now asked to correct the review. Instruction 1. Go to Bb and download two files titled 'Assignment 3' and 'Form'. 2. Open 'Assignment 3', you will the literature review for you to correct. 3. Identify AT LEAST 30 errors and put them down on the 'Form' following the example that shows you in the first row. Errors can be repeated. 4. Identify errors that involve use of wrong terminologies, wrong concept, etc. NOT the writing and grammatical errors. Part 2 (70%) Background Paediatric MRI scan is gaining popularity due to its lack of radiation hazard to the young patients. However, MRI is quite a long scan, which sometimes can be difficult to young patients to keep stationary for a long time. Most of the time, sedation is given to the patients, as well as, to encourage parents to attend the scan with the kid to soothe them through the scan.