FORMS OF PROPERTY RIGHTS AND THE IMPACTS OF CHANGING OWNERSHIP

Land Economics/Use,

Casting And Solidification Technology (CAST): Directional solidification phenomena in a metal model at reduced gravity

The Casting and Solidification Technology (CAST) experiment will study the phenomena that occur during directional solidification of an alloy, e.g., constitutional supercooling, freckling, and dendrite coarsening. The reduced gravity environment of space will permit the individual phenomena to be examined with minimum complication from buoyancy driven flows

An optical study of grain formation: Casting and solidification technology (2-IML-1)

By studying the unidirectional growth of a metal-model material in microgravity, an attempt is made to characterize alloy solidification. Using holograms and supporting temperature measurements obtained during processing in the Fluids Experiment System (FES), the solute and thermal fields associated with the dendrite growth front and extraneous nucleation will be measured and compared to a theoretical (computational) model. Ground based supporting experiments include particle tracking to measure the velocity fields, and optical phase shift techniques (confocal optical signal processing, interferometry, and Schlieren) to study thermal and solutal fields

Ranking the geothermal potential of radiothermal granites in Scotland: are any others as hot as the Cairngorms?

Prior investigations concur that the granite plutons in Scotland which are most likely to prove favourable for geothermal exploration are the Ballater, Bennachie, Cairngorm and Mount Battock plutons, all of which have heat production values greater than 5 μW m−3. This heat production arises from the significant concentrations of potassium, uranium and thorium in some granite plutons. A new field-based gamma-ray spectrometric survey targeted plutons that were poorly surveyed in the past or near areas of high heat demand. This survey identifies several other plutons (Ben Rhinnes, Cheviot, Hill of Fare, Lochnagar and Monadhliath) with heat production rates between 3 and 5 μW m−3 that could well have geothermal gradients sufficient for direct heat use rather than higher temperatures required for electricity generation. The Criffel and Cheviot plutons are examples of Scottish granites that have concentric compositional zonation and some zones have significantly higher (up to 20%) heat production rates than others in the same plutons. However, the relatively small surface areas of individual high heat-production zones mean that it is unlikely to be worthwhile specifically targeting them

Labor and the Labor Process in a Limited Entry Fishery

We examine aspects of labor in the harvesting sector of the surf clam/ocean quahog industry of the mid-Atlantic region of the United States in the context of limited entry. Vessel owners are both diversifying and cutting back on labor costs through crew consolidation in response to difficulties in the sea clam industry. A survey of crew-members on job satisfaction reveals more about the preferences and experiences of labor. We make predictions about the fate of labor under a new management regime based on individual transferable quotas. The analysis is intended to bring the interests of crew-members into the decision-making process and to improve the basis for predicting how future regulatory measures may affect crewing.fishery management, labor, crewing, Atlantic sea clams, limited entry, social impact, Environmental Economics and Policy, Labor and Human Capital, Resource /Energy Economics and Policy,

Gamma-ray spectrometry in the field: Radioactive heat production in the Central Slovakian Volcanic Zone

We report 62 sets of measurements from central-southern Slovakia, obtained using a modern portable gamma-ray spectrometer, which reveal the radioactive heat production in intrusive and extrusive igneous rocks of the Late Cenozoic Central Slovakian Volcanic Zone. Sites in granodiorite of the Štiavnica pluton are thus shown to have heat production in the range ~ 2.2–4.9 μW m− 3, this variability being primarily a reflection of variations in content of the trace element uranium. Sites in dioritic parts of this pluton have a lower, but overlapping, range of values, ~ 2.1–4.4 μW m− 3. Sites that have been interpreted in adjoining minor dioritic intrusions of similar age have heat production in the range ~ 1.4–3.3 μW m− 3. The main Štiavnica pluton has zoned composition, with potassium and uranium content and radioactive heat production typically increasing inward from its margins, reflecting variations observed in other granodioritic plutons elsewhere. It is indeed possible that the adjoining dioritic rocks, hitherto assigned to other minor intrusions of similar age, located around the periphery of the Štiavnica pluton, in reality provide further evidence for zonation of the same pluton. The vicinity of this pluton is associated with surface heat flow ~ 40 mW m− 2 above the regional background. On the basis of our heat production measurements, we thus infer that the pluton has a substantial vertical extent, our preferred estimate for the scale depth for its downward decrease in radioactive heat production being ~ 8 km. Nonetheless, this pluton lacks any significant negative Bouguer gravity anomaly. We attribute this to the effect of the surrounding volcanic caldera, filled with relatively low-density lavas, ‘masking’ the pluton's own gravity anomaly. We envisage that emplacement occurred when the pluton was much hotter, and thus of lower density, than at present, its continued uplift, evident from the local geomorphology, being the isostatic consequence of localized erosion. The heat production in this intrusion evidently plays a significant role, hitherto unrecognized, in the regional geothermics

MARKET SHARE, CAPACITY UTILIZATION, RESOURCE CONSERVATION, AND TRADABLE QUOTAS

This paper examines the impact of the introduction of Individual Transferable Quotas (ITQs) on catch, market share, and capacity utilization of firms in the Mid Atlantic Surf Clam and Ocean Quahog (SCOQ) Fishery. Via the production function framework, catch and market share regression models are utilized in examining the effects of operator size, vessel age, and alternative product catch variables on industrial structure and how such effects changed after ITQs were introduced. Results indicate that in both fisheries, the ITQ system enhanced the value of each vessel by allowing vessel owners to apply greater effort to fewer boats, thus reducing excess capacity in the fishery. Results also indicate an overall resource conservation effect of ITQ introduction in the surf clam fishery. These results suggest that in the presence of ITQs, overall efficiency was enhanced in the SCOQ fishery.Resource /Energy Economics and Policy,

Circadian Rhythm of Brain GABA Levels in the Cockroach, Leucophaea maderae

Brain levels of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) were determined at three-hour intervals in roaches acclimated to a 12-hour lightl12-hour dark cycle (light onset 0600 h) at 25 ± 2° C using high performance liquid chromatography coupled with fluorometnc detection GABA levels were found to be highest at noon and lowest at 1800 h. A difference between the high and low levels at these two times remained during the second day under constant dark conditions, indicating that GABA levels do indeed vary on a circadian basis. Brain GABA levels were highest at a time of day that corresponded with the time of day of greatest clock output measured electrophysiologically. The fact that these two parameters correspond and occur at a time of day when locomotor activity and eye sensitivity to light are low is suggestive that clock output is inhibitory