Locating subsurface gravel with thermal imagery

A method was discussed for using 6 band thermal imagery to locate subsurface gravel deposits in vegetated areas. Geologic history is reviewed to select potential areas of study. An overflight was made using a thermal scanner. The data were processed with a computerized system to delineate areas showing a quartz signature radiated by a gravel deposit. The method was developed during a search for gravel on National Forest land in Louisiana. Processed data from thermal imagery was compared with known gravel deposits and exploratory drill hole logs. A high correlation was noted for a wide range of deposits, from commercial pits to trace deposits only a foot thick. Overburden at these sites varied from zero to sixty feet, near the maximum annual penetration by the thermal wave. It was concluded that the method can be used to locate buried gravel deposits and that more time and effort are needed to verify the usefulness for developing gravel pits adjacent to proposed construction sites

Mercury Levels in Marine and Estuarine Fishes of Florida 1989–2001. 2nd edition revised

The Florida Fish and Wildlife Conservation Commission’s Florida Marine Research Institute (FWC-FMRI) has examined total mercury levels in muscle tissue from a variety of economically and ecologically important species as part of an ongoing study to better understand mercury contamination in marine fishes.The FWC-FMRI Mercury Program is one of the most comprehensive programs in the United States for monitoring mercury levels in marine and estuarine fishes. Because mercury, a toxic metallic element, has been shown to bioaccumulate in fish tissue, humans consuming fish can potentially consume significant levels of mercury.We examined the concentration of total mercury in 6,806 fish, representing 108 species from 40 families. Species represented all major trophic groups, from primary consumers to apex predators.The majority of individuals we examined contained low concentrations of mercury, but concentrations in individual fish varied greatly within and among species. Species with very low mean or median mercury concentrations tended to be planktivores, detritivores, species that feed on invertebrates, or species that feed on invertebrates and small fish prey.Apex predators typically had the highest mercury concentrations. In most species, mercury concentration increased as fish size increased. Sampling in Florida waters is continuing, and future research relating mercury levels to fish age, feeding ecology, and the trophic structure of Florida’s marine and estuarine ecosystems will help us better understand concentrations of this element in marine fishes. (64pp.

Seasonal Occurrence of the White Shark, Carcharodon carcharias, in Waters off the Florida West Coast, with Notes on its Life History

The white shark, Carcharodon carcharias, is considered rare in the Gulf of Mexico; however, recent longline captures coupled with historical landings information suggest that the species occurs seasonally (winter-spring) within this region. We examined a total of seven adult and juvenile white sharks (185-472 em total length) captured in waters off the west coast of Florida. Commercial longline fisheries were monitored for white sharks during all months (1981-94), but this species was captured only from January to April. All white sharks were captured in continental shelf waters from 37 to 222 km off the west coast of Florida when sea surface temperatures ranged from 18.7° to 21.6°C. Depths at capture locations ranged from 20 to 164 m. Fishing gear typically used in Gulf of Mexico offshore fisheries may not be effective at capturing this species, and the apparent rarity of white sharks in this area may be, in part, a function of gear bias

Parasitism of \u3ci\u3ePlathypena Scabra\u3c/i\u3e (Lepidoptera: Noctuidae) by \u3ci\u3eSinophorus Teratis\u3c/i\u3e (Hymenoptera: Ichneumonidae)

(excerpt) A study was conducted at the Ecology Research Center, Miami University, Butler County, Ohio, during the summer of 1990 to examine the effects of strip intercropping sorghum and soybean on the occurrence of parasitoids and incidence of disease in larvae ofthe green cloverworm, Plathypena scabra (F.) (Lepidoptera: Noctuidae), a sporadic pest of soybeans. The details of the experimental design and results are reported elsewhere (Williams et al. 1995)

The effect of elevated hydrostatic pressure on the spectral absorption of deep-sea fish visual pigments

The effect of hydrostatic pressure (0.1-54 MPa, equivalent to pressures experienced by fish from the ocean's surface to depths of ca. 5400 m) on visual pigment absorption spectra was investigated for rod visual pigments extracted from the retinae of 12 species of deep-sea fish of diverse phylogeny and habitat. The wavelength of peak absorption (λmax) was shifted to longer wavelengths by an average of 1.35 nm at 40 MPa (a pressure approximately equivalent to average ocean depth) relative to measurements made at one atmosphere (ca. 0.1 MPa), but with little evidence of a change in absorbance at the λmax. We conclude that previousλ max measurements of deep-sea fish visual pigments, made at a pressure close to 0.1 MPa, provide a good indication ofλ max values at higher pressures when considering the ecology of vision in the deep-sea. Although not affecting the spectral sensitivity of the animal to any important degree, the observed shift inλ max may be of interest in the context of understanding opsin-chromophore interaction and spectral tuning of visual pigments

D-instantons probing D3-branes and the AdS/CFT correspondence

D-instantons are considered as a probe of coinciding $N$ D3-branes. They can feel an external metric via the commutator terms in their effective action. We show that when the D-instantons are separated from the D3-branes, the metric which is probed at the one loop level, {\it exactly} coincides with that of the BPS R-R 3-brane. Interesting connection of this result to the possible explanation of the AdS/CFT correspondence within IKKT M-atrix theory is discussed.Comment: 8pp., Latex. Minor changes, misprints are correcte

DETERMINANTS OF BORROWER DROPOUT IN MICROFINANCE: AN EMPIRICAL INVESTIGATION IN MALI

Repeat borrowing is critical for the long-term financial viability of microfinance institutions (MFIs), which provide financial services to low-income households in developing countries. Repeat borrowers reduce MFI administrative costs, lower risks, and increase institutional productivity. In this paper we study the determinants of borrower dropout of an MFI operating in an urban center in Mali. Specifically, we quantify the explicit and implicit costs that a borrower must incur in obtaining loans from an MFI.Financial Economics,

Theory of the spatial structure of non-linear lasing modes

A self-consistent integral equation is formulated and solved iteratively which determines the steady-state lasing modes of open multi-mode lasers. These modes are naturally decomposed in terms of frequency dependent biorthogonal modes of a linear wave equation and not in terms of resonances of the cold cavity. A one-dimensional cavity laser is analyzed and the lasing mode is found to have non-trivial spatial structure even in the single-mode limit. In the multi-mode regime spatial hole-burning and mode competition is treated exactly. The formalism generalizes to complex, chaotic and random laser media.Comment: 4 pages, 3 figure

Study of effects of space power satellites on life support functions of the earth's magnetosphere

The effects of the Satellite Solar Power System (SSPS) on the life support functions of the earth's magnetosphere were investigated. Topics considered include: (1) thruster effluent effects on the magnetosphere; (2) biological consequences of SSPS reflected light; (3) impact on earth bound astronomy; (4) catastrophic failure and debris; (5) satellite induced processes; and (6) microwave power transmission. Several impacts are identified and recommendations for further studies are provided

Quantum many-body models with cold atoms coupled to photonic crystals

Using cold atoms to simulate strongly interacting quantum systems represents an exciting frontier of physics. However, as atoms are nominally neutral point particles, this limits the types of interactions that can be produced. We propose to use the powerful new platform of cold atoms trapped near nanophotonic systems to extend these limits, enabling a novel quantum material in which atomic spin degrees of freedom, motion, and photons strongly couple over long distances. In this system, an atom trapped near a photonic crystal seeds a localized, tunable cavity mode around the atomic position. We find that this effective cavity facilitates interactions with other atoms within the cavity length, in a way that can be made robust against realistic imperfections. Finally, we show that such phenomena should be accessible using one-dimensional photonic crystal waveguides in which coupling to atoms has already been experimentally demonstrated