Nutrients in waters on the inner shelf between Cape Charles and Cape Hatteras

The distribution of nutrients in the shelf waters of the southern tip of the Middle Atlantic Bight was investigated. It is concluded that the outflow of freshwater from the Chesapeake Bay is a potential source of nutrients to the adjacent shelf waters. However, a quantitative estimation of its importance cannot yet be made because (1) there are other sources of nutrients to the study area and these sources cannot yet be quantified and (2) the concentrations of nutrients in the outflow from Chesapeake Bay exhibit significant short-term and long-term temporal variabilities

Value Computations in Ventral Medial Prefrontal Cortex during Charitable Decision Making Incorporate Input from Regions Involved in Social Cognition

Little is known about the neural networks supporting value computation during complex social decisions. We investigated this question using functional magnetic resonance imaging while subjects made donations to different charities. We found that the blood oxygenation level-dependent signal in ventral medial prefrontal cortex (VMPFC) correlated with the subjective value of voluntary donations. Furthermore, the region of the VMPFC identified showed considerable overlap with regions that have been shown to encode for the value of basic rewards at the time of choice, suggesting that it might serve as a common valuation system during decision making. In addition, functional connectivity analyses indicated that the value signal in VMPFC might integrate inputs from networks, including the anterior insula and posterior superior temporal cortex, that are thought to be involved in social cognition

Measurement of vortex flow fields

A 3-D laser fluorescence anemometer (LFA) was designed, built, and demonstrated for use in the Langley 16 x 24 inch Water Tunnel. Innovative optical design flexibility combined with compact and portable data acquisition and control systems were incorporated into the instrument. This will allow its use by NASA in other test facilities. A versatile fiber optic system facilities normal and off-axis laser beam alignment, removes mirror losses and improves laser safety. This added optical flexibility will also enable simple adaptation for use in the adjacent jet facility. New proprietary concepts in transmitting color separation, light collection, and novel prism separation of the scattered light was also designed and built into the system. Off-axis beam traverse and alignment complexity led to the requirement for a specialized, programmable transverse controller, and the inclusion of an additional traverse for the off-axis arm. To meet this challenge, an 'in-house' prototype unit was designed and built and traverse control software developed specifically for the water tunnel traverse applications. A specialized data acquisition interface was also required. This was designed and built for the LFA system

Boundary Dissipation in a Driven Hard Disk System

A simulation is performed aiming at checking the existence of a well defined stationary state for a two dimensional system of driven hard disks when energy dissipation takes place at the system boundaries and no bulk impurities are presentComment: 5 pages, 7 figure

Effect of Steaming and Hot-Water Soaking on Extractive Distribution and Moisture Diffusivity in Southern Pine During Drying

Samples of southern pine sapwood and heartwood were treated five different ways: steaming in the saturated condition for 1 h and 5 h, respectively, steaming at a moisture content near the fiber saturation point (FSP) for 1 h, hot-water soaking for 10 h, and steaming near 95% relative humidity at an equilibrium moisture content (EMC) slightly below the FSP for 1 h at 100°C. The samples were dried from near saturation condition to an EMC slightly below the FSP, and then to final 12% EMC. The results indicate that the amount of extractives removed tended to be evenly distributed along the flow direction before drying and after drying to near FSP, which suggests that extractives move with water in wood in response to moisture gradient during drying. Hot-water soaking and prolonged steaming increased the moisture diffusivities above and below the FSP. The variation in diffusion coefficient was partially due to changes in the extractive distribution profile

Shrinkage of Outerwood, Middlewood, and Corewood of Two Sweetgum Trees

Two sweetgum (Liquidambar styraciflua L.) trees were used to determine the shrinkage properties of green outerwood, middlewood, and corewood. Samples were taken at various heights along the boles from each side of a disk. Shrinkage displayed the following general pattern: corewood > middlewood > outerwood. This pattern was reversed for the specific gravity of samples from each of these wood types from tree 1, but tree 2 maintained a relatively uniform specific gravity among wood types

Effect of Hardwood Vessels on Longitudinal Moisture Diffusion

The hypothesis that the longitudinal moisture content profile follows the shape of the sorption isotherm under steady-state diffusion condition was confirmed. This phenomenon was explained in terms of the unrestricted flow of water vapor from the lumen of one vessel element to the lumen of the next vessel element. Despite the assumed high vapor transport efficiency of the vessels, other cell types were believed to contribute substantially to longitudinal moisture movement. The diffusion coefficients of three different hardwood species were found to vary with moisture content