NASTRAN solutions of problems described by simultaneous parabolic differential equations

NASTRAN solution techniques are shown for a numerical analysis of a class of coupled vector flow processes described by simultaneous parabolic differential equations. To define one physical problem type where equations of this form arise, the differential equations describing the coupled transfers of heat and mass in mechanical equilibrium with negligible mass average velocity are presented and discussed. Also shown are the equations describing seepage when both electrokinetic and hydrodynamic forces occur. Based on a variational statement of the general problem type, the concepts of scalar transfer elements and parallel element systems are introduced. It is shown that adoptation of these concepts allows the direct use of NASTRAN's existing Laplace type elements for uncoupled flow (the heat transfer elements) for treating multicomponent coupled transfer. Sample problems are included which demonstrate the application of these techniques for both steady-state and transient problems

Population Responses of Wood Frog (Rana Sylvatica) Tadpoles to Overwintered Bullfrog (Rana Catesbeiana) Tadpoles

A fundamental goal in ecology is to understand how environmental variation influences the distribution of individuals within a population. In this study, we used laboratory experiments to examine the population responses of sympatric Wood Frog (Rana sylvatica) tadpoles to native overwintered Bullfrog (Rana catesbeiana) tadpoles. For periods of up to two weeks, we measured growth, activity, and refuge use of Wood Frog tadpoles in small mesocosms with and without an overwintered Bullfrog tadpole present. Bullfrog tadpoles had a negative effect on the growth of Wood Frog tadpoles allotopic (naive) to Bullfrogs, whereas the presence of Bullfrogs had no effect on growth of syntopic (experienced) Wood Frog tadpoles. There were also differential behavioral responses of the Wood Frog populations to overwintered Bullfrog tadpole visual and chemical cues. Only allotopic Wood Frog tadpoles decreased activity levels and increased use of refugia in the presence of overwintered Bullfrog tadpoles. These observations indicate overwintered Bullfrog tadpoles might exert a selective pressure on sympatric Wood Frog tadpoles, and that experience might allow for the development of strategies to maximize performance for species coexisting with overwintered Bullfrog tadpoles

Evaluation of a New Method for Measuring Salamanders

Collection of morphometric data is essential to many field studies of amphibian populations. One of the most common measurements obtained from salamanders is snout-to-vent length (SVL), a parameter useful in studies of sexual dimorphism (Bovero et al. 2003), demography (Semlitsch 1985), and systematics (Carlin 1997). Measuring salamander lengths in the field is challenging because of their small size, slimy texture, and propensity to maintain a nonlinear body position. Time expenditure is another concern, especially when researchers process large numbers of salamanders. Different measurement techniques vary in accuracy and precision, limiting the reliability of the data so that comparisons cannot be easily performed. We compare a new method of obtaining salamander SVL measurements to other commonly used methods

Intervention Methodologies Targeting Vulnerable Youth in Frankfort, Kentucky: Measuring Developmental Assets

Results from the Kentucky State University Youth Empowerment Project (KSU-YEP) are presented. The results of this study indicate that increases in the factors that support positive health outcomes can be achieved if interventions are developed and implemented with community involvement and inclusion of the target population’s values and norms

Valuation of pollination services from habitat management: a case study of utility scale solar energy facilities in the United States

Creating and maintaining pollinator habitats following the ecological infrastructure concept in degraded or unutilized land, such as solar energy facilities, is a practical way to synergistically advance the food, energy, and ecology nexus. Given the large land-use requirements for solar farming—the fastest growing renewable energy technology–considerable attention has been focused on strategies to maximize multiple ecosystem services. In this study, we coupled the principles of agronomy and ecology with economics and integrated national-scale data on crops, pollinators, and solar facilities to identify locations for creating pollinator habitats and estimating the economic value of pollination from the habitats. We examined opportunities for pollination services from pollinator-friendly utility-scale solar facilities adjacent to 42 million hectares of pollination-dependent crops in the conterminous United States at high resolution of 1 ha. We used the net income method to estimate the potential economic value of creating habitat in the land adjacent to solar facilities in the eight states with the greatest number of solar installations. Creating pollinator habitats at the 217 utility-scale solar facilities in these states could support adjacent 80,000 hectares of high pollinator dependent crops, which could potentially generate a pollination value of 120 USD to 264 million USD. The location-specific information and high-resolution maps generated for the United States demonstrate integration of grey and green infrastructure to support the food, energy, and environment nexus