Animal studies have shown that an acute stressor in close temporal proximity to immune challenge can enhance the response to delayed-type hypersensitivity and antibody response to vaccination. The current study examined the effect of acute exercise or mental stress prior to influenza vaccination on the subsequent antibody response. Sixty young healthy adults (31 men, 29 women) were randomly allocated to one of three task conditions: dynamic exercise, mental stress, or control. After an initial baseline, participants completed their allocated 45min task and then received the influenza vaccine. Plasma cortisol and interleukin-6 were determined at the end of baseline, after the task, and after recovery. Antibody titres were measured prevaccination and at 4 weeks and 20 weeks post-vaccination follow-ups. Women in both the exercise and mental stress conditions showed higher influenza antibody titres at both than those in the control condition, while men responded similarly in all conditions. Interleukin-n recovery was found to be a significant predictor of subsequent influenza antibody response in women. In line with animal research, the current study provides preliminary evidence that acute stress can enhance the antibody response to vaccination in humans.

Which of the following variables is an effect modifier of the relationship between the exposure and outcome?

Group of answer choices

Gender

Influenza antibody response

Group assignment (dynamic exercise, mental stress, or control)

Influenza vaccination

None of the listed answers

Question 1 Recall the univariate EDA tools by summarizing them in a table like the one below. Univariate EDA Numerical Summaries Graphical Summaries Quantitative (a) what are they? (b) what are they? Categorical (c) what are they? (d) what are they? Question 2 We will cover tools for bivariate quantitative EDA later on. We'll do some quantitative vs categorical EDA in this lab. Bivariate EDA Numerical Summaries Graphical Summaries Quantitative us Quantitative Correlation (Ch 3) Scatterplot (Ch 3) Quantitative us Categorical soe la (a) what is it? Categorical us Categorical Frequencies & rel. frequencies Odds Ratio (binary vs binary) Contingency Table (Ch 8)\fMath 3073 HW # 2, spring 2016 Due on Monday 02/22/2016 NAME: 2 1 0 1. Let A= =1 3 5 Find a non-singular matrix P such that PA is a RREF of A 2. Suppose A is a non-singular matrix. Show that if 48 =0, then 8=0Consider the general two-state continuous-time Markov chain with transition rates Q = A 0 (a) lJ'il'rite down the backward equations. (b) Show that for any t 3 D, 1110116) + angt} = A. (e) Solve the backward equations. You may use the fact that the solution of the ordinary differential equation .r'(t) = r1226) + Mt) is :r(t) = 12(0):!\" + eat/u e_\"b(s}ds. Consider a three-state continuous-time Markov chain in which the transition rates are given by The states are labelled 1 and 2. on Q: zoo ion The states are labelled 1, 2 and 3. (a) Write down the transition matrix of the corresponding embedded Markov chain as well as the transition rates out of each of the three states. (b) Use the symmetry of Q to argue that this setting can be reduced to one with only 2 states. (:3) Use the results of Problem 1 to solve the backward equations of this 3-state Markov chain