I solve boundary-value problems for an idealized thrust block moving over a detachment surface and ramp, and produce theoretical bed-duplication folds in the thrust block that closely resemble the Powell Valley anticline in the southern Appalachian Mountains. The anticline is narrow and rounded if the translation is small, and broad and flat-topped if the translation is large. The limbs of the anticline are symmetric if drag is zero. Drag along the ramp part of the detachment surface can explain the asymmetry of dips of the two limbs of the Powell Valley anticline, particularly if drag between relatively competent rocks in opposition at the ramp causes an initial anticline to form as the thrust block begins to move, and then drag reduces markedly as relatively soft shales at the base of the block were thrust over competent rocks in the ramp.
Roots of white ash have a better configuration than roots of sugar maple for anchoring shallow colluvium against landsliding on hillslopes along the Ohio River and its tributaries in southwestern Ohio. The landslides are in a shallow layer of colluvium, about one meter thick, overlying shale and limestone bedrock. The sliding hillsides range in slope angle from 16 to 36 degrees and the roots which penetrate shear surfaces are anchored in the weathered bedrock and help to hold landmasses in place. The hillsides are covered by a mesophytic forest, locally known as a ravine community, dominated by white ash, sugar maple and sweet buckeye. Sugar maple is the most common species on the landslides; its roots do not penetrate the soil as deeply as the roots of the white ash.
Filtration theory was developed by engineers to model the removal of particulate matter from industrial gases. Recently, it has been used by biologists and paleo-biologists to model the capture of food particles by filter feeding organisms. The purpose of this study was to test paleosynecologic (biofacies-level) and paleoautecologic (species-level) models of crinoid distribution utilizing filtration theory. These models were tested by analyzing the crinoid faunas of three transgressive-regressive sequences from the Upper Pennsylvanian Lansing Group of midcontinent North America.
The temporal subdomain method based on the Ritz-Galerkin method is investigated as a method for the solution of space-time dependent neutron dynamics equations. In the temporal subdomain finite element method, the time domain is divided into subdomains and within each subdomain the unknown coefficients of the time dependent trial functions are determined by making the residual of an appropriate functional orthogonal to the step function.
According to this poll, when asked to compare the prevalence of the stereotypical view that scientists are most likely to be white males to 10 years ago, 60% of science educators said that more students are aware that scientists can come from any demographic group. In the same poll, 55% of science educators said their students still see scientists as most likely to be males. [...]25% said that although more students (compared to 10 years ago) are aware that science can be a diverse field, they do not connect those opportunities with their own demographic group. Teachers can promote the idea that science provides a useful foundation for a variety of careers either in science or that build on science (ASPIRES 2013). [...]teachers can demonstrate the importance of learning science, regardless of career aspirations, by empowering students to weigh in, in an informed manner, on scientific questions important to their lives, such as those that appear in the news or government debates. [...]teachers might help their students better understand climate science by engaging them in the Smithsonian Environmental Research Center's Invader ID citizen science project where they would help identify invasive marine invertebrates in order to track changes in coastal environments.
The Aspen Grove landslide, central Utah, occurred in older landslide debris. The debris is about 6-15 meters thick, and consists of medium- to high-plasticity clays and silty clays. Persistent landslide structures, including toes, hollows, and flank ridges, outline dimly preserved landslide masses in the older debris.
In the 1990's the incidence of eating disorders among college aged females had increased (Johnston & Christropher, 1991) with specific concern for female college athletes. A 1992 NCAA study found that 70% of responding institutions reported at least one case of an eating disorder with the highest prevalence in gymnastics, cross country, swimming, and track (Dick, 1993).
Hyperelastic constitutive models of soft tissue mechanical behavior are extensively used in applications like computer-aided surgery, injury modeling, etc. While numerous constitutive models have been proposed in the literature, an objective method is needed to select a parsimonious model that represents the experimental data well and has good predictive capability. This is an important problem given the large variability in the data inherent to soft tissue mechanical testing.
In this work, we discuss a Bayesian approach to this problem based on Bayes factors. We propose a holistic framework for model selection, wherein we consider four different factors to reliably choose a parsimonious model from the candidate set of models. These are the qualitative fit of the model to the experimental data, evidence values, maximum likelihood values, and the landscape of the likelihood function. We consider three hyperelastic constitutive models that are widely used in soft tissue mechanics: Mooney-Rivlin, Ogden and exponential. Three sets of mechanical testing data from the literature for agarose hydrogel, bovine liver tissue, porcine brain tissue are used to calculate the model selection statistics. A nested sampling approach is used to evaluate the evidence integrals. In our results, we highlight the robustness of the proposed Bayesian approach to model selection compared to the likelihood ratio, and discuss the use of the four factors to draw a complete picture of the model selection problem.
Dr. Deborah Duran is the director of NIMHD’s Office of Science Policy, Strategic Planning, Analysis, Reporting, and Data (OSPARD). She has 20 years of experience in organizational strategic planning, system assessments, science policy, measures, metrics, data management, performance monitoring, and reporting. Dr. Duran leads two branches within OSPARD: Science Planning, Policy, and Reporting; and Data, Assessments, Resources, and Evaluation. OSPARD serves NIMHD planning, assessment, analysis, and reporting needs and coordinates trans-NIH minority health and health disparities planning and reporting requirements. Dr. Duran hopes to help NIMHD become the centralized source of minority health and health disparities biomedical data, policies, and scientific advances.
Dr. Duran has spent much of her NIH career serving as performance director in the NIH Office of the Director, handling a wide range of responsibilities, including program performance monitoring, budget performance integration, organization performance assessments, and strategic planning. She designed a centralized online reporting system, currently used by NIH and the U.S. Department of Health and Human Services (HHS), to assist in the collection, analysis, and communication of organization performance information.
Dr. Duran trained in social psychology and virus research, statistics, evaluation, counseling, and computer science. She has experience as an educator, principal investigator, advocate, researcher, consultant, and counselor. Her areas of interest include system science, population health, Hispanic health, behavior research, cancer, coping, end-of-life care, palliative care, data systems, data management, and training minority youth.
Dr. Duran has a Ph.D. in social psychology with a minor in research methodologies and statistics. In 2000 and in 2004, Dr. Duran earned the HHS Secretary’s Award for Distinguished Service.
Stylolites in twelve stratigraphic sections of the Salem Limestone, distributed throughout the Illinois Basin, provide clues to their origin and development. Chemical and X-ray diffraction analyses reveal that stylolite seam material contains organic matter and clay minerals too sparse or absent in the host limestone to be considered solely as insoluble residue. Stylolite distribution in various lithofacies suggests that stylolites develop along thin sedimentary layers rich in organic matter and clay minerals. Stylolite density (vertical distribution) mimics the distribution of organic-rich sedimentary layers: sparse but thick in grainstone, and abundant but thin in packstone and wackestone. Many stylolites grade laterally into organic-rich layers, or hummocky seams. Thicknesses of stylolite caps and hummocky seams are approximately equal in the same host rock, but hummocky seams tend to be more laterally continuous. Stylolite density in packstone increases with burial depth, whereas hummocky seam density decreases. Hummocky seam thickness does not change with depth. Stylolite column height in grainstone, which is sparse in hummocky seams, increases with depth, whereas stylolite density does not increase. This list of observations supports the hypothesis that stylolites develop along pre-existing, organic-rich layers, or hummocky seams, rather than nucleating in pure host rock and creating organic-rich seams as accumulations of insoluble residue. Volumetric calculations indicate that the contribution of stylolites to pore-filling cement is 5 to 25 percent throughout the Illinois Basin.
Cambrian sedimentation of the Rome trough in eastern Kentucky was studied using 85 wells supplemented by available cuttings and cores. Most conclusions are based on cross sections, isopach and structure maps, and the environmental interpretation of geophysical logs. Thin section petrology played a supplementary role.