Advances in semantic representation for multiscale biosimulation: a case study in merging models

As a case-study of biosimulation model integration, we describe our experiences applying the SemSim methodology to integrate independently-developed, multiscale models of cardiac circulation. In particular, we have integrated the CircAdapt model (written by T. Arts for MATLAB) of an adapting vascular segment with a cardiovascular system model (written by M. Neal for JSim). We report on three results from the model integration experience. First, models should be explicit about simulations that occur on different time scales. Second, data structures and naming conventions used to represent model variables may not translate across simulation languages. Finally, identifying the dependencies among model variables is a non-trivial task. We claim that these challenges will appear whenever researchers attempt to integrate models from others, especially when those models are written in a procedural style (using MATLAB, Fortran, etc.) rather than a declarative format (as supported by languages like SBML, CellML or JSim’s MML)

Using multiple reference ontologies: Managing composite annotations

There are a growing number of reference ontologies available across a variety of biomedical domains and current research focuses on their construction, organization and use. An important use case for these ontologies is annotation—where users create metadata that access concepts and terms in reference ontologies. We draw on our experience in physiological modeling to present a compelling use case that demonstrates the potential complexity of such annotations. In the domain of physiological biosimulation, we argue that most annotations require the use of multiple reference ontologies. We suggest that these “composite” annotations should be retained as a repository of knowledge about post-coordination that promotes sharing and interoperation across biosimulation models

Integration of multi-scale biosimulation models via light-weight semantics

Currently, biosimulation researchers use a variety of computational environments and languages to model biological processes. Ideally, researchers should be able to semi- automatically merge models to more effectively build larger, multi-scale models. How- ever, current modeling methods do not capture the underlying semantics of these models sufficiently to support this type of model construction. In this paper, we both propose a general approach to solve this problem, and we provide a specific example that demon- strates the benefits of our methodology. In particular, we describe three biosimulation models: (1) a cardio-vascular fluid dynamics model, (2) a model of heart rate regulation via baroreceptor control, and (3) a sub-cellular-level model of the arteriolar smooth mus- cle. Within a light-weight ontological framework, we leverage reference ontologies to match concepts across models. The light-weight ontology then helps us combine our three models into a merged model that can answer questions beyond the scope of any single model

Food Insecurity Rates Rise Steeply with Recession

Children's HealthWatch finds that the prevalence of food insecurity in a five-city sample of low-income families with young children increased from 18.5 percent to 22.6 percent between 2007 and 2008. This is the largest year-to-year change seen in the dataset since 2001. The increase is an indication of the economic hardships facing low-income families with young children. This data suggests that we are likely to see significant increases in food insecurity when the U.S. Department of Agriculture issues its own statistics for 2008 in late fall

Even Very Low Levels of Food Insecurity Found to Harm Children's Health

This publication is the first in a series of Children's HealthWatch Policy Action Briefs, which will provide a summary of our research, as well as that of others, on issues affecting children's health and well-being. This brief finds that more children are at risk for health and developmental problems due to lack of food than were previously thought. These children and their families are classified as

Federal Programs that Protect Young Children's Health

An investment in children's health is an investment in our country's economic health. Infants and toddlers, whose bodies and brains are in their most rapid period of growth, are uniquely vulnerable to even shortterm deprivation. Ensuring that they have the basic physiologic building blocks for healthy bodies and minds is not only the right thing to do -- it is the smart thing to do. Research has shown that children who suffer from poor nutrition, unstable housing and inadequate home heating have a greater likelihood of poor health, a higher risk of developmental delays and, in some cases, an increased risk of hospitalization

Holocene variations in the Scottish marine radiocarbon reservoir effect

We assessed the evidence for variations in the marine radiocarbon reservoir effect (MRE) at coastal, archaeological Iron Age sites in north and west Scotland by comparing AMS measurements of paired marine and terrestrial materials (4 pairs per context). DeltaR values were calculated from measurements on material from 3 sites using 6 sets of samples, all of which were deposited around 2000 BP. The weighted mean of the DeltaR determinations was -79 +/- 17 C-14 yr, which indicates a consistent, reduced offset between atmospheric and surface ocean C-14 specific activity for these sites during this period, relative to the present day (DeltaR = similar to0 C-14 yr). We discuss the significance of this revised AR correction by using the example of wheelhouse chronologies at Hornish Point and their development in relation to brochs. In addition, we assess the importance of using the concepts of MRE correction and AR variations when constructing chronologies using C-14 measurements made on materials that contain marine- derived carbon

Affordable Health Care Keeps Children and Families Healthy

The health of young children is negatively affected when parents have to forego health care for themselves or other adult members of the household or when parents have to forego payment of household expenses in order to pay for health care