Every year research institutions produce petabytes of data. Yet, only a small percent of the data is readily accessible for analysis. Terra Populus acts as the bridge between big data sources and researchers. Researchers are provided convenient web applications that allow them to access, analyze, and tabulate different datasets under a common platform. Terra Populus is developing three unique applications. The first application, Paragon, is a prototype parallel spatial database, which aims to extend the functionality of PostgreSQL and PostGIS onto multinode systems. Terra Populus Tabulator application employs Parquet on Spark to build dynamic queries for analyzing large population survey data. The last application, Terra Explorer, is an exploratory analysis tool for visualizing the spatial datasets within the repository.

BACKGROUND: Atrial fibrillation (AF) is less prevalent in women versus men, but associated with higher risks of stroke and death in women. The role hormone therapy plays in AF is not well understood. METHODS AND RESULTS: The Women's Health Initiative randomized postmenopausal women to placebo or conjugated equine estrogens (0.625 mg/d) plus medroxyprogesterone acetate (2.5 mg/d) if they had a uterus (N=16 608) or to conjugated equine estrogens only if they had prior hysterectomy (N=10 739). Incident AF was identified by ECG and diagnosis codes from Medicare claims or hospitalization records. Hazard ratios for incident AF were estimated using Cox proportional hazards regression. After excluding participants with baseline AF, there were 611 incident AF cases over a mean of 5.6 years among 16 128 estrogen plus progestin participants, and 683 cases over a mean of 7.1 years among 10 251 conjugated equine estrogens alone participants. Incident AF was more frequent in the active groups of both trials, reaching statistical significance in the trial of conjugated equine estrogens alone in women with prior hysterectomy (hazard ratio, 1.17; CI, 1.00-1.36; P=0.045) and in the pooled analysis (hazard ratio, 1.12; CI, 1.00-1.24; P=0.05), but not in the estrogen plus progestin trial (hazard ratio, 1.07; CI, 0.91-1.25; P=0.44). These results were only minimally affected by adjustment for incident stroke, coronary heart disease, and heart failure. CONCLUSIONS: Incident AF was modestly elevated in hysterectomized women randomized to postmenopausal E-alone, and in the pooled group randomized to E-alone or estrogen plus progestin. The trend in women with intact uterus receiving estrogen plus progestin, considered separately, was not statistically significant. CLINICAL TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov; Identifier: NCT00000611.

Terra Populus, part of NSFs new DataNet initiative, will develop organizational and technical infrastructure to integrate, preserve, and disseminate data describing changes in the human population and environment over time. A plethora of high-quality environmental and population datasets are available, but they are widely dispersed, have incompatible or inadequate metadata, and have incompatible geographic identifiers. The new infrastructure will enable researchers to identify and merge data from heterogeneous sources to study the relationships between human behavior and the natural world. Terra Populus will partner with data archives, data producers, and data users to create a sustainable international organization that will guarantee preservation and access over multiple decades.

In this paper, we present a hybrid approach, robust principal component geographically weighted regression (RPCGWR), in examining urbanization as a function of both extant urban land use and the effect of social and environmental factors in the Twin Cities Metropolitan Area (TCMA) of Minnesota. We used remotely sensed data to treat urbanization via the proxy of impervious surface. We then integrated two different methods, robust principal component analysis (RPCA) and geographically weighted regression (GWR) to create an innovative approach to model urbanization. The RPCGWR results show significant spatial heterogeneity in the relationships between proportion of impervious surface and the explanatory factors in the TCMA. We link this heterogeneity to the sprawling nature of urban land use that has moved outward from the core Twin Cities through to their suburbs and exurbs.