Energy, climate and water in the 21st century – Texas and Florida share a strong connection with future challenges in the Earth sciences

Bureau of Economic Geolog

Developing Mathematics Enrichment Workshops for Middle School Students: Philosophy and Sample Workshops

This paper describes our approach to organizing enrichment activities using advanced mathematics topics for diverse audiences of middle school students. We discuss our philosophy and approaches for the structure of these workshops, and then provide sample schedules and resource materials. The workshops cover activities on the following topics: Graphing Calculators; The Chaos Game; Statistical Sampling; CT Scans–the reconstruction problem; The Platonic and Archimedean solids; The Shape of Space; Symmetry; The Binary Number System and the game of NIM; Graph Theory: Proof by Counterexample

Spontaneous Symmetry Breaking for Driven Interacting Particles on Triangular Substrates

For collectively interacting repulsive particles driven on triangular substrates, we show that for certain directions of drive a spontaneous symmetry breaking phenomena occurs where the particles can flow in one of two directions that are not aligned with the external drive, giving rise to a positive or negative Hall current. Along these directions, the particle flow is highly ordered, while in the direction of the drive the flow is disordered. We also find a number of dynamical phase transitions and unusual hysteretic properties that arise due to the symmetry breaking properties of the flows.Comment: 4 pages, 4 postscript figure

A Comparative Life Cycle Assessment between a Metered Dose Inhaler and Electric Nebulizer

Life cycle assessment (LCA) evaluates the environmental impact of a product based on the materials and processes used to manufacture the item as well as the item’s use and disposal. The objective of this LCA was to evaluate and compare the environmental impact of a metered dose inhaler, specifically the Proventil® HFA inhaler (Merk & Co., Inc., Kenilworth, NJ, USA), and an electric nebulizer, specifically the DeVilbiss Pulmo-Aide® nebulizer (DeVilbiss, Port Washington, NY, USA). GaBi LCA software was used to model the global warming potential (GWP) of each product by using substantiated data and well-justified assumptions for the components, manufacturing, assembly, and use of both devices. The functional unit used to model each device was one dose of the active drug, albuterol sulfate. The inhaler’s GWP, 0.0972 kg CO2-eq, was greater than the nebulizer’s even when uncertain parameters were varied ±100x. During the use phase ofa the inhaler, which accounted for approximately 96% of the inhaler’s total GWP, HFA 134a is used as a propellant to deliver the drug. The total GWP for the electric nebulizer was 0.0294 kg CO2-eq assuming that the mouthpiece was cleaned in a dishwasher, while it was 0.0477 kg CO2-eq when the nebulizer mouthpiece was hand washed between uses. The GWP breakeven scenario between dishwashing and hand washing occurred when the mouthpiece accounted for 10% of the dishwasher load

New GOES satellite synchronized time code generation

The TRAK Systems' GOES Satellite Synchronized Time Code Generator is described. TRAK Systems has developed this timing instrument to supply improved accuracy over most existing GOES receiver clocks. A classical time code generator is integrated with a GOES receiver