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TEM (Transmission Electronic Microscopy) can reach higher magnification and resolution than SEM (Scanning Electronic Microscopy)

Why is the study of failure important?

A good failure analysis consists of completing as many steps in the process as possible

What was the failure problem with tin cans? 

Root cause analysis is done to identify the most obvious underlying cause of a failure.

Failure analysis always leads to a correctable root cause of failure.

Below are two statements about inverse probability weighting: 1. Inverse probability weighting assumes that the estimates of the exposure-outcome effect are constant across strata of the confounder. 2. Inverse probability weighting creates a pseudo-population in which the confounder and exposure are no longer associated. Which of the statements are true? 

Suppose a team of researchers is interested in conducting a retrospective cohort study to determine if occupational arsenic exposure is a cause of liver cancer among American Adults. The researchers are concerned that geographic location (e.g., Northeast, Southwest, Midwest) may be a confounder of the effect of occupational arsenic exposure on liver cancer. The researchers decide to use restriction to minimize confounding by geographic location. Please describe the following: How restriction can be applied in the context of this study (3 points). How restriction minimizes confounding by geographic location in the context of this study (3 points). 

A team of researchers conducted a prospective cohort study to determine if children who were exposed to secondhand smoke at home are more likely to develop asthma compared to children who were not exposed to secondhand smoke at home. The researchers computed a risk ratio of 1.72 and a standard error of 0.17. As a next step the researchers want to estimate a 95% confidence interval for the risk ratio using the following formula: What value should the researchers use in place of  in the formula?

Smoking during pregnancy is often mentioned as a cause of birth defects, such as cleft lip. However, not all babies born to mothers who smoked during pregnancy develop cleft lip. Use the sufficient cause framework to explain why not all babies born to mothers who smoked during pregnancy develop cleft lip (max. 6 points). Make sure to include the terms component cause and sufficient cause in your answer (max. 6 points).