Mediation analysis for a survival outcome with time-varying exposures, mediators, and confounders

We propose an approach to conduct mediation analysis for survival data with time-varying exposures, mediators, and confounders. We identify certain interventional direct and indirect effects through a survival mediational g-formula and describe the required assumptions. We also provide a feasible parametric approach along with an algorithm and software to estimate these effects. We apply this method to analyze the Framingham Heart Study data to investigate the causal mechanism of smoking on mortality through coronary artery disease. The risk ratio of smoking 30 cigarettes per day for ten years compared with no smoking on mortality is 2.34 (95 % CI = (1.44, 3.70)). Of the overall effect, 7.91% (95% CI: = 1.36%, 19.32%) is mediated by coronary artery disease. The survival mediational g-formula constitutes a powerful tool for conducting mediation analysis with longitudinal data

VII Zw 403: H I structure in a blue compact dwarf galaxy

‘In these times, during the rise in the popularity of institutional repositories, the Society does not forbid authors from depositing their work in such repositories. However, the AAS regards the deposit of scholarly work in such repositories to be a decision of the individual scholar, as long as the individual's actions respect the diligence of the journals and their reviewers.’ Original article can be found at : http://iopscience.iop.org/ Copyright American Astronomical SocietyWe present optical (UBVJ), ultraviolet (FUV, NUV), and high-resolution atomic hydrogen (H I) observations of the nearby blue compact dwarf (BCD), VII Zw 403. We find that VII Zw 403 has a relatively high H I mass-to-light ratio for a BCD. The rotation velocity is nominally 10-15 km s(-1), but rises to similar to 20 km s(-1) after correction for the similar to 8-10 km s(-1) random motions present in the gas. The velocity field is complex, including a variation in the position angle of the major axis going from the northeast to the southwest parts of the galaxy. Our high-resolution Hi maps reveal structure in the central gas, including a large, low-density Hi depression or hole between the southern and northern halves of the galaxy, coincident with an unresolved X-ray source. Although interactions have been proposed as the triggering mechanism for the vigorous star formation occurring in BCDs, VII Zw 403 does not seem to have been tidally triggered by an external interaction, as we have found no nearby possible perturbers. It also does not appear to fall in the set of galaxies that exhibit a strong central mass density concentration, as its optical scale length is large in comparison to similar systems. However, there are some features that are compatible with an accretion event: optical/Hi axis misalignment, a change in position angle of the kinematic axis, and a complex velocity field.Peer reviewe

Thoughts II

According to the Preface, this book was “prepared in response to a number of requests which have come from Dr. Tyler’s friends and from those who have read the first volume, which was published in 1963” (p. v). Like its predecessor, it is a collection of articles published in two newspapers: the Advertiser in Huntington, West Virginia, and the Gazette in Charleston. Those articles were shortened versions of “sermons prepared and delivered by Dr. Tyler over a period of sixty years in the ministry.”https://mds.marshall.edu/tyler_sroger/1001/thumbnail.jp

Thoughts

According to the title page, the book is a collection of articles published in two newspapers: the Advertiser in Huntington, West Virginia, and the Gazette in Charleston. Those articles were “based on sermons prepared and delivered by Dr. Tyler over a period of sixty years in the ministry.”https://mds.marshall.edu/tyler_sroger/1000/thumbnail.jp