Understanding climate: A strategy for climate modeling and predictability research, 1985-1995

The emphasis of the NASA strategy for climate modeling and predictability research is on the utilization of space technology to understand the processes which control the Earth's climate system and it's sensitivity to natural and man-induced changes and to assess the possibilities for climate prediction on time scales of from about two weeks to several decades. Because the climate is a complex multi-phenomena system, which interacts on a wide range of space and time scales, the diversity of scientific problems addressed requires a hierarchy of models along with the application of modern empirical and statistical techniques which exploit the extensive current and potential future global data sets afforded by space observations. Observing system simulation experiments, exploiting these models and data, will also provide the foundation for the future climate space observing system, e.g., Earth observing system (EOS), 1985; Tropical Rainfall Measuring Mission (TRMM) North, et al. NASA, 1984

Variatio Delectat Consumer Demand for Food Diversity

Whereas a large number of empirical studies have been devoted to analysing consumer demand for specific products, much less attention has been paid to the household?s demand for product variety (the number of different products consumed in a specific time period). This paper analyses consumer demand for food variety in Germany. The econometric analysis of 4.632 household in 1995 suggests, that variety increases with income and the number of children aged between 6 and 18 years and is significantly higher if the family lives in larger cities in East-Germany, and the housekeeping person is not additionally working full-time. A single male household consumes a significantly smaller number of different food products. The significant (and positive) impact of household income on food variety is in line with the hypothesis that consumption evolves along a hierarchical order as income increases. --

A plasma solenoid driven by an Orbital Angular Momentum laser beam

A tens of Tesla quasi-static axial magnetic field can be produced in the interaction of a short intense laser beam carrying an Orbital Angular Momentum with an underdense plasma. Three-dimensional "Particle In Cell" simulations and analytical model demonstrate that orbital angular momentum is transfered from a tightly focused radially polarized laser beam to electrons without any dissipative effect. A theoretical model describing the balistic interaction of electrons with laser shows that particles gain angular velocity during their radial and longitudinal drift in the laser field. The agreement between PIC simulations and the simplified model identifies routes to increase the intensity of the solenoidal magnetic field by controlling the orbital angular momentum and/or the energy of the laser beam

Dynamical model for the formation of patterned deposits at receding contact lines

We describe the formation of deposition patterns that are observed in many different experiments where a three-phase contact line of a volatile nanoparticle suspension or polymer solution recedes. A dynamical model based on a long-wave approximation predicts the deposition of irregular and regular line patterns due to self-organised pinning-depinning cycles corresponding to a stick-slip motion of the contact line. We analyze how the line pattern properties depend on the evaporation rate and solute concentration

The Taste for Variety: A Hedonic Analysis

Based on the model of consumers' variety-seeking behavior introduced by Anderson et al. (1992), this paper derives a hedonic price function for a households' consumption bundle. The price a consumer pays for her consumption bundle reflects the values of the underlying attributes of goods purchased but also accounts for any preference for variety that she might have. The empirical analysis is conducted for 3,240 German households and their expenditure on 182 different soft drinks over a six-month period. We find that consumers have a preference for variety in food consumption, ceteris paribus. Furthermore, the per-unit price is found to be significantly larger for higher income households, as well as households where the principal wage earner has a high level of education. Larger households tend to spend less on soft drinks per unit.consumer demand, taste for variety, food products, hedonic analysis, Germany, Food Consumption/Nutrition/Food Safety, C21, D12,

Thin film evolution equations from (evaporating) dewetting liquid layers to epitaxial growth

In the present contribution we review basic mathematical results for three physical systems involving self-organising solid or liquid films at solid surfaces. The films may undergo a structuring process by dewetting, evaporation/condensation or epitaxial growth, respectively. We highlight similarities and differences of the three systems based on the observation that in certain limits all of them may be described using models of similar form, i.e., time evolution equations for the film thickness profile. Those equations represent gradient dynamics characterized by mobility functions and an underlying energy functional. Two basic steps of mathematical analysis are used to compare the different system. First, we discuss the linear stability of homogeneous steady states, i.e., flat films; and second the systematics of non-trivial steady states, i.e., drop/hole states for dewetting films and quantum dot states in epitaxial growth, respectively. Our aim is to illustrate that the underlying solution structure might be very complex as in the case of epitaxial growth but can be better understood when comparing to the much simpler results for the dewetting liquid film. We furthermore show that the numerical continuation techniques employed can shed some light on this structure in a more convenient way than time-stepping methods. Finally we discuss that the usage of the employed general formulation does not only relate seemingly not related physical systems mathematically, but does as well allow to discuss model extensions in a more unified way

One step closer to a better starling trap

European starlings (Sturnus vulgaris) are an invasive species in the United States that damage agriculture, personal property, and threaten human health and safety. The U.S. Department of Agriculture Wildlife Services provides technical support to mitigate damage by controlling starling populations at concentrated animal feeding operations, landfills, utilities, and urban areas. Wildlife Services uses DRC-1339, a registered toxicant, to reduce starling populations. Trapping can also be an effective tool but requires more time at a higher cost than DRC-1339. Trapping starlings, however, may be needed to provide a viable alternative to mitigate damage in areas where toxicant use may be restricted. To address this need, I developed a unique and effective starling trap to increase catch rates. I began testing multiple trap designs in November 2007 at cattle (Bos taurus) feedlots, meat processing plants, and urban staging areas in a 45-km radius of the city of Omaha, Nebraska, USA. In December 2011, I designed a 4-chamber, basket-style starling trap that has been instrumental in a nearly 90% reduction of the roosting starling population in downtown Omaha. Herein, I discuss the development and testing of the trap and provide guidelines and instructions for building and strategic placement of the trap