Chabauty-Coleman experiments for genus 3 hyperelliptic curves

We describe a computation of rational points on genus 3 hyperelliptic curves $C$ defined over $\mathbb{Q}$ whose Jacobians have Mordell-Weil rank 1. Using the method of Chabauty and Coleman, we present and implement an algorithm in Sage to compute the zero locus of two Coleman integrals and analyze the finite set of points cut out by the vanishing of these integrals. We run the algorithm on approximately 17,000 curves from a forthcoming database of genus 3 hyperelliptic curves and discuss some interesting examples where the zero set includes global points not found in $C(\mathbb{Q})$.Comment: 18 page

Experimental Research of Influence of a Relative Particles Positioning in a Gas Stream on Characteristics of their Aerodynamic Traces

The cycle of experimental studies on determination of length of aerodynamic traces of the particles which are flowed round by an air stream is executed. When carrying out researches, panoramic optical methods for diagnostics of multiphase flows of PIV and PTV were used. Velocities of an air flow were varied in the range of 1-3 m/s. The sizes of particles changed from 1mm to 5 mm. The defining influence of the sizes of particles and velocities of an air stream on length of aerodynamic traces is established. Influence of a relative positioning of particles on features of formation of an aerodynamic trace is shown

A Comparison of Data Sources for Motor Vehicle Crash Characteristic Accuracy

Objective: To determine the accuracy of police reports (PRs), ambulance reports (ARs), and emergency department records (EDRs) in describing motor vehicle crash (MVC) characteristics when compared with an investigation performed by an experienced crash investigator trained in impact biomechanics. Methods: This was a cross-sectional, observational study. Ninety-one patients transported by ambulance to a university emergency department (ED) directly from the scene of an MVC from August 1997 to April 1998 were enrolled. Potential patients were identified from the ED log and consent was obtained to investigate the crash vehicle. Data describing MVC characteristics were abstracted from the PR, AR, and medical record. Variables of interest included restraint use (RU), air bag deployment (AD), and type of impact (TI). Agreements between the variables and the independent crash investigation were compared using kappa. Interrater reliability was determined using kappa by comparing a random sample of 20 abstracted reports for each data source with the originally abstracted data. Results: Agreement using kappa between the crash investigation and each data source was 0.588 (95% CI = 0.508 to 0.667) for the PR, 0.330 (95% CI = 0.252 to 0.407) for the AR, and 0.492 (95% CI = 0.413 to 0.572) for the EDR. Variable agreement was 0.239 (95% CI = 0.164 to 0.314) for RU, 0.350 (95% CI = 0.268 to 0.432) for AD, and 0.631 (95%= 0.563 to 0.698) for TI. Interrater reliability was excellent (kappa > 0.8) for all data sources. Conclusions: The strength of the agreement between the independent crash investigation and the data sources that were measured by kappa was fair to moderate, indicating inaccuracies. This presents ramifications for researchers and necessitates consideration of the validity and accuracy of crash characteristics contained in these data sources.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75653/1/j.1553-2712.2000.tb02067.x.pd

Modeling stomatal and nonstomatal effects of water deficits on CO2 fixation in a semiarid grassland

Sherpa Romeo green journal. Permission to archive final published versionThe confidence with which we can model water deficit effects on grassland productivity is limited by uncertainty about the mechanisms, stomatal and nonstomatal, by which soil water deficits reduce CO2 uptake. We propose that these reductions can accurately be modeled from a combination of stomatal effects on gaseous CO2 diffusion and nonstomatal effects on biochemical CO2 fixation. These effects can be combined through a solution for the intercellular CO2 concentration (Ci) at which rates of diffusion and fixation are equal for each leaf surface in the canopy. In this model, both stomatal and nonstomatal effects are driven by a common indicator of plant water status calculated in a hydraulically-driven scheme of soil-plant-atmosphere water transfer. As part of the ecosystem model ecosys, this combined model simulated concurrent declines in latent heat effluxes and CO2 influxes measured by eddy covariance during soil drying in a drought-affected semiarid grassland. At the same time, the model simulated the declines in Ci at which CO2 fixation occurred during soil drying as calculated from seasonal measurements of phytomass d13C. Alternative model formulations based on stomatal or nonstomatal effects alone simulated these declines in CO2 influxes and in Ci less accurately than did the formulation in which these effects were combined. We conclude that modeling water deficit effects on CO2 fixation requires the concurrent simulation of stomatal and nonstomatal effects. As part of a larger ecosystem model, this combined model can be used to assess climate effects on grassland productivity.Ye

Discovery and Description of a Sphagnum Bog in Iowa, With Notes on the Distribution of Bog Plants in the State

This Sphagnum bog is located in Dead Man\u27s Lake, Pilot Knob State Park, Hancock Co., Iowa. The county is in the center of the state east and west and is in the second tier of counties from the north, just south of Winnebago Co., which, in turn, borders Minnesota. Pilot Knob Park is in the northeastern part of the county, half in Section 3 and half in Section 4 of Ellington Township (97-23). It is right at the northern border of the county and three miles west of the eastern border. It can be reached by driving 3.5 miles east from Forest City (Winnebago Co.) on U.S. 9, and going south for a mile on Iowa 332 to the entrance at the northwest corner of the park. The park is an irregular mass of morainic hills, formed of pebbly Mankato (Wisconsin) drift, with marshy and boggy depressions in between, with Pilot Knob (1450\u27), by far the most outstanding of these hills, towering about 300\u27 above the level of Lime Creek, to the southwest, and 100\u27 above Dead Man\u27s Lake. For a description of the forest, mostly oak, which covers the whole upland area, see Macbride (1903) Forestry Notes for Hancock Co. Oak wilt has caused much tree destruction in the last three years. Pilot Knob early attracted considerable attention, and received its name from it use as a landmark, to pilot the traveller. This is not only the finest morainic mound thus far described in Iowa, but is one of the finest in the whole country (Ibid. :90). The amazing height, for Iowa prairie country, excited various writers to a free use of superlatives: From the top of Pilot Knob a larger area of fertile land may be seen than from anywhere else on this earth I believe (Secor, 1919:128)

Waccamaw regional economic outlook Summer 2014

Coastal Carolina University publishes the Waccamaw Regional Economic Outlook providing information on the economic activity of the Grand Strand Region in employment, sales real estate, construction, tourism and projects

Waccamaw regional economic outlook Spring 2014

Coastal Carolina University publishes the Waccamaw Regional Economic Outlook providing information on the economic activity of the Grand Strand Region in employment, sales real estate, construction, tourism and projects