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Which procedure removes all the pulpal tissues in the pulp chamber and stops 1–3 mm short of the apex?

3. Accurate segmentation of medical images is critical for disease diagnosis and treatment planning. Different segmentation methods are used in medical imaging, such as identifying brain tumors in MRI scans. 3.1 How can you determine whether the noise present in an MRI image (Fig. 4) is Gaussian noise or salt-and-pepper noise? How does this noise affect medical image analysis, particularly segmentation? 3.2a If you are operating the MRI scanner, how can you improve the signal to noise ratio? List at least one method. 3.2b If you already acquired this image, before segmenting the brain region, preprocessing techniques can improve image quality.  b.1) List two denoising techniques that can enhance the segmentation of the MRI image. b.2) Comparing acquisition-based SNR improvement vs. post-processing denoising. If you have the option to choose between improving SNR during acquisition vs. applying post-processing denoising, which would be the better choice and why? 3.3 Please provide at least three image segmentation methods, excluding thresholding, that have been applied to medical images in the course. 3.4 After segmentation, some regions of the brain appear disconnected or contain small holes inside the segmented area. What image processing method could you use to fill in the missing areas or connect small hole regions.

2. If you have acquired a DICOM image, it is necessary to identify the most relevant areas of the image based on the anatomical structure. 2.1 Explain briefly the differences between DICOM and standard gray-level images. Additionally, if a rectangle ROI on a given image (Fig. 1) is p1= (82, 140), p2=(182,140), p3=(80, 280), and p4= (182, 280), the ROI focuses on the key anatomical structure (heart). If the image resolution is 1.5mm x 1.5mm, what is the length and width of the heart? 2.2 Assuming you already have an ROI in this image, and a point processing function , how would you modify the image in Figure 2? What is the maximum value of the modified image? Please note that is the original image and is the modified image. 2.3 If we apply the point processing function to the image, what would be the maximum value of the resulting image and why? 2.4 What value of ‘a’ in the point processing function

This is a short answer question regarding biotechnology, horizontal gene transfer, and gene expression.  Be complete & specific as possible with your answer for full credit.  Biorad scientists created a pGlo plasmid using recombinant DNA technology. This pGlo plasmid contained an ampicillin resistance gene and placed the jellyfish green fluorescent protein gene (GFP) under the control of the arabinose operon.  The green fluorescent protein glows green under UV light.  The SCC microbiology students took this genetically engineered pGlo plasmid and transformed Escherichia coli.  The students placed a portion of the bacteria from the control tube and the experimental tube onto the appropriate media types as shown in the photo.  (legend:  LB = nutrient medium; +Amp = contains ampicillin; +Ara= contains arabinose).   The top two plates were controls 1) showing that the bacteria were alive after being treated with the transformation chemical and heat shocking, and 2) the antibiotic, ampicillin, was indeed effective against the bacteria used in this experiment.  What information can be gained from the bottom two plates in this experiment? When answering this question, 1) identify the plate by media type then 2) describe what information was gained from it and the reason behind your answer. 

A nonsense mutation is a substitution of a base in the DNA sequence that creates a stop codon. 

See the previous question. Alice and Bob are using the Diffie-Hellman scheme. Charlie wants to interfere with their use of it.  Give the full name for the type of attack that Charlie is likely to attempt: 

General purpose data (files, messages, webpages, etc.) should be encrypted / decrypted in  mode HINT: Provide the full name

See the previous question.  Describe in words the inverse of the operation performed above.  

Suppose that someone in your neighborhood is monitoring your Wi-Fi. The payload of every data packet is encrypted, so that person cannot read your data.  They notice that every time you send several packets to a certain IP address, one or more packages from Amazon are delivered the next day.  The next time you interact with that website, they watch your porch and steal some packages.    That person’s process of monitoring your Wi-Fi and concluding it is related to Amazon deliveries is best categorized as …  

Suppose you browse to a website that presents a typical X.509 certificate chain, containing three (3) certificates.  The certificate at the bottom of the chain is for the website.  You browser shows that the certificate is verified.  Which of the following is/are true about the certificate at the top of the chain?