Design and Construction of Drilled Shafts in Karst Environments of Florida

Drilled shafts have been widely used as bridge foundation alternatives for more than a decade in Florida. The majority of the drilled shafts are designed to embed into the underlying limestone. However, many unforeseen conditions have been encountered during the construction of drilled shafts due to karst environments, especially in the Tampa Bay area where sinkhole occurrences are common. This paper presents a case history of the design and construction of drilled shaft foundations for the I-4/I-275 Downtown Interchange in Tampa, Florida. A two-phase procedure utilized by the Florida Department of Transportation (FDOT) was adopted to minimize the impact of karst environments on drilled shaft construction and contractors’ claims, while also considering the project schedule and budget. A total of 315 drilled shafts with total lengths of 3,914 meters were installed for this project. Although the estimated total drilled shaft lengths in the preliminary design phase were only underestimated by 10%, high variability of individual shaft lengths between those estimated during the preliminary and final designs were observed with a maximum difference up to 20 m. The evaluation of the impacts of the karst environments on the drilled shaft design, and the comparison and discussion of the drilled shaft lengths determined during design and as-built are presented

Reflection and Remembrance: Oral histories and critical thinking

The research assignment for this class was to interview someone who lived through World War II. The interviewee could be someone who served in the military service, someone on the home front or even a child-anyone who was touched by the experience of World War II

Out in the country: Rural sexual minority mothers

Rural and urban sexual minority mothers\u27 parenting experiences related to sexual orientation were compared. Participants were 414 mothers in same-sex relationships with at least one child under the age of 18 years living in their home who was planned with their current partner. Rural mothers were more likely to be biological parents and not adoptive parents. Ruralmothers reported higher rates of discrimination from strangers and people in service or helping professions. Although outness for rural and urban mothers did not differ, for children, classmates\u27 parents and neighbors were less likely to know the family\u27s status in rural areas. Rural and urban mothers did not differ on internalized homophobia, social support, or stigma consciousness. Clinical and policy implications are discussed

Out in the country: Rural sexual minority mothers

Rural and urban sexual minority mothers\u27 parenting experiences related to sexual orientation were compared. Participants were 414 mothers in same-sex relationships with at least one child under the age of 18 years living in their home who was planned with their current partner. Rural mothers were more likely to be biological parents and not adoptive parents. Ruralmothers reported higher rates of discrimination from strangers and people in service or helping professions. Although outness for rural and urban mothers did not differ, for children, classmates\u27 parents and neighbors were less likely to know the family\u27s status in rural areas. Rural and urban mothers did not differ on internalized homophobia, social support, or stigma consciousness. Clinical and policy implications are discussed

Lifestyle and the aging brain: interactive effects of modifiable lifestyle behaviors and cognitive ability in men from midlife to old age

We examined the influence of lifestyle on brain aging after nearly 30 years, and tested the hypothesis that young adult general cognitive ability (GCA) would moderate these effects. In the community-dwelling Vietnam Era Twin Study of Aging (VETSA), 431 largely non-Hispanic white men completed a test of GCA at mean age 20. We created a modifiable lifestyle behavior composite from data collected at mean age 40. During VETSA, MRI-based measures at mean age 68 included predicted brain age difference (PBAD), Alzheimer's disease (AD) brain signature, and abnormal white matter scores. There were significant main effects of young adult GCA and lifestyle on PBAD and the AD signature (ps ≤ 0.012), and a GCA-by-lifestyle interaction on both (ps ≤ 0.006). Regardless of GCA level, having more favorable lifestyle behaviors predicted less advanced brain age and less AD-like brain aging. Unfavorable lifestyles predicted advanced brain aging in those with lower age 20 GCA, but did not affect brain aging in those with higher age 20 GCA. Targeting early lifestyle modification may promote dementia risk reduction, especially among lower reserve individuals