A threshold caloric test- results in normal subjects

Threshold caloric test on normal subjects - responses to hot and cold caloric stimulatio

Comparison of medium frequency pulsed radar interferometer and correlation analysis winds, part 2

In order to test whether the chosen Doppler peaks represent localized scatters in motion, as opposed to some sort of integrated composite, an attempt was made to determine the change in position of single scatterers over a series of sequential records. A four-antenna system was employed which had 1 degree of freedom in phase. Due to limitations N-S linear transmission and E-W linear reception were used. The Doppler frequency peak selection criteria were that at least two of the four power spectra should have a local peak, and that normalized phase discrepancy, should be less than 0.3. The lack of success in tracking individual scatters seems to suggest a short lifetime. If this is the case, then the present experiment is not able to resolve the difference found between the correlation analysis true velocity and the interferometer value. On the other hand, it appears that the interferometer may be of some use in tracking waves

Measurement of the horizontal velocity of wind perturbations in the middle atmosphere by spaced MF radar systems

Two remote receiving sites have been set up at a distance of approx 40 km from the main MF radar system. This allows measurement of upper atmosphere winds from 60-120 km (3 km resolution) at the corners of an approximately equilateral triangle of side approx 20 km. Some preliminary data are compared through cross correlation and cross spectral analysis in an attempt to determine the horizontal velocity of wind perturbations and/or the horizontal wavelength and phase velocity of gravity waves

Bulk Density of a Sandy Loam: Traffic, Tillage, and Irrigation-Method Effects

Modern crop production creates a cycle between soil compaction caused by traffic and alleviation of this condition by tillage or natural processes such as freezing and thawing. The objective of this study was to evaluate important management practices as they relate to changes in bulk density of a tilled sandy loam soil. Practices evaluated were irrigation method, time between tillage and traffic, tire pressure and wheel load of applied traffic, and controlled traffic. Relationships among bulk density, penetration resistance, and infiltration rate were determined. Experiments were conducted in the San Joaquin Valley of California, on a sandy loam soil (Entisol) with an organic-matter content of <1%. After tillage, settling and trafficking of a soil resulted in rapid changes in its bulk density until a new equilibrium was reached. Tire pressure of 408 kPa and wheel weight of 2724 kg applied at moisture contents near field capacity resulted in a bulk density of 1.92 Mg m-3 , compared with a value of 1.67 for no traffic. The time interval between tillage and traffic did not affect final bulk density. Drip irrigation, which did not saturate the soil, resulted in a bulk density of ≈0.1 Mg m-3 lower than flood irrigation, which saturated the soil surface. Wheel traffic in the furrow resulted in only small changes in the bulk density within the row. When tillage did not occur between cropping seasons, traffic caused high bulk densities in the furrow but only small changes in the row. An increase in bulk density from 1.7 to 1.89 Mg m-3 decreased the infiltration rate by four times and increased resistance to penetration at the end of the season by three times. Knowledge of how management practices affect bulk density can aid growers in reducing recompaction following tillage

Teleological Essentialism

Placeholder essentialism is the view that there is a causal essence that holds category members together, though we may not know what the essence is. Sometimes the placeholder can be filled in by scientific essences, such as when we acquire scientific knowledge that the atomic weight of gold is 79. We challenge the view that placeholders are elaborated by scientific essences. On our view, if placeholders are elaborated, they are elaborated Aristotelian essences, a telos. Utilizing the same kinds of experiments used by traditional essentialists—involving superficial change (study 1), transformation of insides (study 2), acquired traits (study 3) and inferences about offspring (study 4)—we find support for the view that essences are elaborated by a telos. And we find evidence (study 5) that teleological essences may generate category judgments