426 research outputs found
Persistence and degradation of dieldrin and heptachlor in soil and effects on plants
Digitized 2007 AES.Includes bibliographical references (pages 26-27)
Poisonous spiders and other venomous arthropods in Missouri
Caption title.Includes bibliographical references
The Mexican bean beetle and its control in Missouri
Caption title.Digitized 2006 AES MoU
Genus Culicoides (Diptera-Ceratopogonidae) in central Missouri : species, seasonal abundance, activity
Digitized 2007 AES.Includes bibliographical references (page 24)
Electric Propulsion Upper-Stage for Launch Vehicle Capability Enhancement
The NASA In-Space Propulsion Technology Project Office initiated a preliminary study to evaluate the performance benefits of a solar electric propulsion (SEP) upper-stage with existing and near-term small launch vehicles. The analysis included circular and elliptical Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) transfers, and LEO to Low Lunar Orbit (LLO) applications. SEP subsystem options included state-of-the-art and near-term solar arrays and electric thrusters. In-depth evaluations of the Aerojet BPT-4000 Hall thruster and NEXT gridded ion engine were conducted to compare performance, cost and revenue potential. Preliminary results indicate that Hall thruster technology is favored for low-cost, low power SEP stages, while gridded-ion engines are favored for higher power SEP systems unfettered by transfer time constraints. A low-cost point design is presented that details one possible stage configuration and outlines system limitations, in particular fairing volume constraints. The results demonstrate mission enhancements to large and medium class launch vehicles, and mission enabling performance when SEP system upper stages are mounted to low-cost launchers such as the Minotaur and Falcon 1. Study results indicate the potential use of SEP upper stages to double GEO payload mass capability and to possibly enable launch on demand capability for GEO assets. Transition from government to commercial applications, with associated cost/benefit analysis, has also been assessed. The sensitivity of system performance to specific impulse, array power, thruster size, and component costs are also discussed
High Resolution Observations of Drop Size Distribution for GPM Ground Validation
During the Mid-latitude Continental Convective Cloud Experiment (MC3E), NASA's GPM GV Disdrometer and Radar Observations of Precipitation (DROP) Facility deployed an array of disdrometers and rain gauges in northern Oklahoma to sample, with high resolution, the drop size distribution for use in development of precipitation retrieval algorithms for the GPM core satellites. The DROP Facility instruments deployed during MC3E consisted of 16 autonomous Parsivel units, 5 two-dimensional video disdrometers (2dvds), a vertically pointing K band radar, and 32 tipping bucket rain gauges. There were several rainfall events during MC3E in which rain drops exceeding 6 mm in diameter were recorded. The disdrometer array revealed large rain drops with diameters exceeding 6 mm and 8 mm during two separate stratiform and convective rainfall events, respectively. The NPOL radar, which was scanning in high resolution RHI mode (every 40 sec) over the disdrometer array during the stratiform event, indicated a 1 km thick bright band with a differential reflectivity column of 2-3 dB extending below the melting layer to the surface where the large drops were recorded by the 2dvds. These large drops are important for GPM since they can have a great impact upon satellite precipitation retrieval, especially near the ground and below heavy convective rainfall cores where satellites have had problems depicting the rainfall
Phase-III, Randomized Controlled Trial of the Behavioral Intervention for Increasing Physical Activity in Multiple Sclerosis: Project BIPAMS
Background
We propose a phase-III, randomized controlled trial (RCT) that examines the effectiveness of a behavioral intervention based on social cognitive theory (SCT) and delivered through the Internet using e-learning approaches for increasing physical activity and secondary outcomes (e.g., symptoms) in a large sample of people with multiple sclerosis (MS) residing throughout the United States. Methods/design
The proposed phase-III trial will use a parallel group, RCT design that examines the effect of a 6-month behavioral intervention for increasing physical activity and secondarily improving mobility, cognition, symptoms, and quality of life (QOL) in persons with MS. The primary outcome is accelerometer-measured moderate-to-vigorous physical activity (MVPA). The secondary outcomes include self-report measures of physical activity, walking impairment, cognition, fatigue, depression, anxiety, pain, sleep quality, and QOL. The tertiary outcomes are mediator variables based on SCT. Participants (N = 280) will be randomized into behavioral intervention (n = 140) or attention and social contact control (n = 140) conditions using computerized random numbers with concealed allocation. The conditions will be administered over 6-months by persons who are uninvolved in screening, recruitment, random assignment, and outcome assessment. There will be a 6-month follow-up without intervention access/content. We will collect primary, secondary, and tertiary outcome data every 6 months over the 12-month period. Data analysis will involve intent-to-treat principles and latent growth modeling (LGM). Discussion
The proposed research will provide evidence for the effectiveness of a novel, widely scalable approach for increasing lifestyle physical activity and improving secondary outcomes and QOL in persons with MS
- …