Strength Properties of Waxes at Various Temperatures and Their Practical Application

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66922/2/10.1177_00220345670460013101.pd

Flow of Binary and Tertiary Mixtures of Waxes

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66517/2/10.1177_00220345660450023101.pd

Birth Outcomes in Relation to Prenatal Exposure to Per- and Polyfluoroalkyl Substances and Stress in the Environmental Influences on Child Health Outcomes (ECHO) Program

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are persistent and ubiquitous chemicals associated with risk of adverse birth outcomes. Results of previous studies have been inconsistent. Associations between PFAS and birth outcomes may be affected by psychosocial stress. OBJECTIVES: We estimated risk of adverse birth outcomes in relation to prenatal PFAS concentrations and evaluate whether maternal stress modifies those relationships. METHODS: We included 3,339 participants from 11 prospective prenatal cohorts in the Environmental influences on the Child Health Outcomes (ECHO) program to estimate the associations of five PFAS and birth outcomes. We stratified by perceived stress scale scores to examine effect modification and used Bayesian Weighted Sums to estimate mixtures of PFAS. RESULTS: We observed reduced birth size with increased concentrations of all PFAS. For a 1-unit higher log-normalized exposure to perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS), we observed lower birthweight-for-gestational-age z-scores of formula presented [95% confidence interval (CI): formula presented ], formula presented (95% CI: formula presented ), formula presented (95% CI: formula presented ), formula presented (95% CI: formula presented , 0.06), and formula presented (95% CI: formula presented ), respectively. We observed a lower odds ratio (OR) for large-for-gestational-age: formula presented (95% CI: 0.38, 0.83), formula presented (95% CI: 0.35, 0.77). For a 1-unit increase in log-normalized concentration of summed PFAS, we observed a lower birthweight-for-gestational-age z-score [formula presented ; 95% highest posterior density (HPD): formula presented ] and decreased odds of large-for-gestational-age (formula presented ; 95% HPD: 0.29, 0.82). Perfluorodecanoic acid (PFDA) explained the highest percentage (40%) of the summed effect in both models. Associations were not modified by maternal perceived stress. DISCUSSION: Our large, multi-cohort study of PFAS and adverse birth outcomes found a negative association between prenatal PFAS and birthweight-for-gestational-age, and the associations were not different in groups with high vs. low perceived stress. This study can help inform policy to reduce exposures in the environment and humans. https://doi.org/10.1289/EHP10723

Evaluation of a Tensile Test for Direct Filling Resins

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67602/2/10.1177_00220345700490023801.pd

On the Use of Emerging Design as a Basis for Knowledge Collaboration

Abstract. Abstractions in software engineering have been used for guidance and understanding of software systems. Design in particular is a key abstraction in this regard. However, design is often a static representation that does not evolve with the code and therefore cannot help developers in collaborating after it becomes out-of-date. Our research group is exploring the use of Emerging Design, a dynamic abstraction, as the basis for knowledge collaboration through its implementation in a coordination portal called Lighthouse. This paper presents the state of the art of Lighthouse and discusses three knowledge collaboration problems that we are currently addressing.