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Map Reduce [2 points] The master keeps a scoreboard of workers assigned to map tasks with the intermediate results of the mappers stored at the respective mapper nodes. A new engineer proposes centralizing all intermediate results at the master “to simplify reducer fetches.”   Give ONE pro and ONE con of this proposal. 

RioVista The context for this question is the same as the previous question. A program using Vista and running on a system with the Rio file cache is trying to atomically update the variables foo and bar within a transaction, where both are within the specified data range. The initial value of each is set to TRUE. Within the transaction, foo is set to FALSE and later bar is set to FALSE. For each question, explain your choice using 1-2 succinct bullets. d) [2 points ] The system crashes just after setting the value of foo. It then crashes again during the recovery process. Does the second crash affect the contents of the persisted data after recovery?

CDN [2 points] Giant-scale services introduced the terms “yield” and “harvest” through the DQ principle.  A CDN that uses eventual consistency to keep the content of the mirror sites in sync is also an example of a giant-scale service. Explain with succinct bullets, how you can relate those terms to such a CDN?  

Under the Articles of Confederation, each state delegation at the National Congress

Which specific protein is responsible for the characteristic “tight attachment” of E. coli O157:H7 to the host’s intestinal mucosa?

Colonization resistance may involve “exploitative competition,” in which microbes compete for attachment to host cells. 

If a microbial community is permanently altered by a disturbance, but it continues to perform like the original community, this is an example of which of the following:

Staphylococcus aureus is an example of a pathogenic skin microbe that:

Staphylococcus aureus utilizes Protein A (SpA) to evade the host immune system. Which of the following best describes the primary mechanism by which SpA inhibits opsonophagocytosis?

The five pillars of [woundhealing], or catabasis, include removal of microbes, dead cells, and debris, restoration of vascular integrity, regeneration of tissue, remission from fever, and [reliefofpain].