Synthetic aperture radar images of ocean waves, theories of imaging physics and experimental tests

The physical mechanism for the synthetic Aperture Radar (SAR) imaging of ocean waves is investigated through the use of analytical models. The models are tested by comparison with data sets from the SEASAT mission and airborne SAR's. Dominant ocean wavelengths from SAR estimates are biased towards longer wavelengths. The quasispecular scattering mechanism agrees with experimental data. The Doppler shift for ship wakes is that of the mean sea surface

Air-Sea Spray Airborne Radar Profiler Characterizes Energy Fluxes in Hurricanes

A report discusses ASAP (Air-sea Spray Airborne Profiler), a dual-wavelength radar profiler that provides measurement information about the droplet size distribution (DSD) of sea-spray, which can be used to estimate heat and moisture fluxes for hurricane research. Researchers have recently determined that sea spray can have a large effect on the magnitude and distribution of the air-sea energy flux at hurricane -force wind speeds. To obtain information about the DSD, two parameters of the DSD are required; for example, overall DSD amplitude and DSD mean diameter. This requires two measurements. Two frequencies are used, with a large enough separation that the differential frequency provides size information. One frequency is 94 GHz; the other is 220 GHz. These correspond to the Rayleigh and Mie regions. Above a surface wind speed of 10 m/ s, production of sea spray grows exponentially. Both the number of large droplets and the altitude they reach are a function of the surface wind speed

Comparison of Metabolic Variables during the 2-Minute Walk Test and 6-Minute Walk Test

Assessing for functional mobility and fitness in deconditioned populations is common practice in many clinics. Comparison of the 2-minute walk test (2MWT) as a predictor for 6-minute walk test (6MWT) metabolic variables will save clinicians time and effort when performing baseline testing. PURPOSE: To determine if the 2MWT can be used as a viable means of accessing baseline fitness versus the 6MWT. METHODS: Ten subjects (48.3±15.7 yrs, 168.5±8.6 cm, 75.5±13.6 kg) reported on two separate days to perform the tests. Once fitted with a heart rate (HR) monitor and portable O2 analyzer, they performed either the 2MWT or 6MWT and on the second day performed the other. Repeated measures ANOVA were used to determine significant differences with pairwise comparisons utilizing the Bonferroni technique. Alpha was set at .05 for all tests. RESULTS: While there was no significant difference in VO2 between the 2-min time point of the 2MWT (16.9±4.6 ml/kg/min) and the 2-min time point of the 6-min walk test (17.1±5.6 ml/kg/min), p=1.0, there was a significant difference between the 2-min time point of the 2MWT and the 6-min time point of the 6MWT (21.4±4.6 ml/kg/min), p=. 007. There was no significant difference in HR between any of the time points (p\u3e.05). CONCLUSION: Caution should be taken if using the 2MWT as a measure of fitness since it seems participants are not yet in steady state at the 2-minute mar

Community Capacity Building: Supporting Military Children and Families Environmental Scan of Extension Professional Development Opportunities for Early Childhood and School-Age Providers: Final Report

The purpose of this environmental scan was to discover what professional development is offered through the Cooperative Extension System to early childhood or school age providers across the nation. A secondary focus was to assess the availability of professional development opportunities offered through the Cooperative Extension System for providers who serve children (birth–12) from military families, both on and off installation. Through this process, the strengths of Extension were highlighted and existing resources that could be replicated for use in other states were identified

Vertebrate Natural History Notes from Arkansas, 2017

Because meaningful observations of natural history are not always part of larger studies, important pieces of information often are unreported. Small details, however, can fills gaps in understanding and also lead to interesting questions about ecological relationships or environmental change. We have compiled recent observations of foods, reproduction, record size, parasites, and distribution of 30 species of fishes, new records of distribution and parasites of 2 species of amphibians, and new records of distribution, parasites, reproduction and anomalies of 11 species of mammals