A Training Course for the Underserved Population

Micro Business Development is a non-profit organization that assists the underserved community of Denver, Colorado in moving into the formal business economy by providing access to capital, training, and marketplace opportunities. It is in need of the instructional design and development of a training course that would inform their clients about E-Business and web site design. This nonformal training course will not only assist their clients expand their client base, but also help them to become more established, and increase the visibility of their businesses. This paper describes a Service Capstone Project that will be a beneficial solution to an adult learning problem for a local community-based organization

Utilization of Heat Sensitivity in Crotalidae

Specimens of five genera of snakes (Crotalus, Agkistrodon, Bitis, Epicrates, and Elaphe) were tested for use of thermal cues in food selection. Results indicate that pit vipers (Crotalus and Agkistrodon) and boas (Epicrates) utilize thermal radiation in selection of food. It was also indicated that Crotalus (rattlesnakes) do not invariably show a reflexive strike before food is investigated or ingested

Utilization of Heat Sensitivity in Crotalidae

Specimens of five genera of snakes (Crotalus, Agkistrodon, Bitis, Epicrates, and Elaphe) were tested for use of thermal cues in food selection. Results indicate that pit vipers (Crotalus and Agkistrodon) and boas (Epicrates) utilize thermal radiation in selection of food. It was also indicated that Crotalus (rattlesnakes) do not invariably show a reflexive strike before food is investigated or ingested

An Analytical Expression for R50% Dependent on PTV Surface Area and Volume: A Cranial SRS Comparison

The intermediate dose spill for a stereotactic radiosurgery (SRS) plan can be quantified with the metric R50%, defined as the 50% isodose cloud volume (VIDC50%) divided by the volume of the planning target volume (PTV). By coupling sound physical principles with the basic definition of R50%, we derive an analytical expression for R50% for a spherical PTV. Our analytical expression depends on three quantities: the surface area of PTV (SAPTV), the volume of PTV (VPTV), and the distance of dose drop-off to 50% (Δr). The value of ∆r was obtained from a simple set of cranial phantom plan calculations. We generate values from our analytical expression for R50% (R50%Analytic) and compare the values to clinical R50% values (R50%Clinical) extracted from a previously published SRS data set that spans the VPTV range from 0.15 to 50.1 cm3. R50%Analytic is smaller than R50%Clinical in all cases by an average of 15% ± 7%, and the general trend of R50%Clinical vs VPTV is reflected in the same trend of R50%Analytic. This comparison suggests that R50%Analytic could represent a theoretical lower limit for the clinical SRS data; further investigation is required to confirm this. R50%Analytic could provide useful guidance for what might be achievable in SRS planning

A Measure of SRS/SRT Plan Quality: Quantitative Limits for Intermediate Dose Spill (R50%) in Linac-Based Delivery

Stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) of multiple cranial targets using a single isocenter on conventional C-arm linear accelerators are rapidly developing clinical techniques. However, no universal guidelines for acceptable intermediate dose spill limits are currently available or widely accepted. In this work, we propose an intermediate dose spill guidance range for cranial SRS/SRT delivered on C-arm linacs with MLC collimation for single PTV plans and single isocenter multiple target plans with PTV volumes in the range 0.02–57.9 cm3. We quantify intermediate dose spill with the R50% metric (R50% = volume of 50% of prescription isodose cloud / volume of PTV) and test the proposed range using three clinical data sets, containing both 6 MV and 10 MV beams, previously published by other authors. Our proposed lower limit of R50% (LowerR50%) and upper limit of acceptable R50% (UpperR50%) bound over 90% of the clinical data used in this study, yet still provide a challenging benchmark for optimization and plan assessment of linac-based, MLC collimated SRS/SRT

Structural and dielectric studies of the phase behaviour of the topological ferroelectric La1-xNdxTaO4

We thank the University of St Andrews and EPSRC (via DTG studentships to CALD and JG) for funding,The layered perovskite LaTaO4 has been prepared in its polar orthorhombic polymorphic form at ambient temperature. Although no structural phase transition is observed in the temperature interval 25° C < T < 500 °C, a very large axial thermal contraction effect is seen, which can be ascribed to an anomalous buckling of the perovskite octahedral layer. The non-polar monoclinic polymorph can be stabilised at ambient temperature by Nd-doping. A composition La0.90Nd0.10TaO4 shows a first-order monoclinic-orthorhombic (non-polar to polar) transition in the region 250° C < T < 350 °C. Dielectric responses are observed at both the above structural events but, despite the ‘topological ferroelectric’ nature of orthorhombic LaTaO4, we have not succeeded in obtaining ferroelectric P–E hysteresis behaviour. Structural relationships in the wider family of AnBnX3n+2 layered perovskites are discussed.Publisher PDFPeer reviewe

Laboratory Model of Magnetic Frictionless Flywheel and Hoverboard

We constructed a ring Halbach array of strong NdBeB grade 52 arc-segment magnets, with magnetizations chosen to create a one-sided magnet with the field magnified on the flat side. We investigated a repulsive axial levitating forces and associated circumferential drag forces acting on an assembly of inductors suspended above the rotating array. After measuring induced currents, voltages and magnetic fields in the individual inductors (in the form of short solenoids) of our induction wheels, we investigated the dependence of lift/drag forces on the speed of relative rotation of magnets and inductors. The ratio of lift to drag increases uniformly with the angular velocity, as expected from a related theory of the induction effects in linear motion. We experimented with the shape and density of the various inductive loads made from air core inductors, and with their nonmagnetic conductive material to maximize lift. We have achieved a maximum lift of some 20% of the inductor assembly’s weight at our limiting speed of 2500 rpm. More development is still needed in order to obtain better and more accurate results. Eventually this design could have applications as frictionless bearings or as frictionless gear in a wide range of systems, especially in machinery that cannot be easily accessed. This paper has implications for ideas to build frictionless flywheels and hover boards