bluuebunny/crossref_metadata_2025 huggingface dataset:
Geothermal System at 21°N, East Pacific Rise: Physical Limits on Geothermal Fluid and Role of Adiabatic Expansion
Authors: Bischoff James L.
Published: October 2006

Pressure-volume-temperature relations for water at the depth of the magma chamber at 21°N on the East Pacific Rise suggest that the maximum subsurface temperature of the geothermal fluid is about 420°C. Both the chemistry of the discharging fluid and thermal balance considerations indicate that the effective water/rock ratios in the geothermal system are between 7 and 16. Such low ratios preclude effective metal transport at temperatures below 350°C, but metal solubilization at 400°C and above is effective even at such low ratios. It is proposed that the 420°C fluid ascends essentially adiabatically and in the process expands, cools, and precipitates metal sulfides within the upper few hundred meters of the sea floor and on the sea floor itself.
Evaporation of Seawater: Calculated Mineral Sequences
Authors: Harvie Charles E. , Weare John H. , Hardie Lawrence A. , Eugster Hans P.
Published: October 2006

Van't Hoff's predictions of the mineral sequences to be expected on the evaporation of seawater are based on an oversimplified system. New computer calculations that include calcium-bearing phases are in better agreement with natural occurrences, removing discrepancies that have plagued evaporite geologists for nearly a century. A new hydrologic model that combines equilibrium batch evaporation with fractionation between successive batches is proposed to account for the mineral sequences observed in such classic deposits as the German Zechstein.
Sweden Beyond Oil: Nuclear Commitments and Solar Options
Authors: Lönnroth M. , Johansson T. B. , Steen P.
Published: October 2006

The project "Energy and Society," sponsored by the Swedish Secretariat for Futures Studies, has studied different indigenous energy sources as alternatives to imported oil in Sweden. One alternative is nuclear energy, another is renewable energy. Large uncertainties are associated with both alternatives today. The main characteristics of an energy policy for the rest of the century that does not foreclose either of these options have been identified. Such a policy will have to be based on an understanding of similarities and differences between the alternatives. A nuclear and a solar energy system have been outlined as a basis for an analysis of technical, economic, and institutional issues.
Stratospheric Ozone, Middle Ultraviolet Radiation, and Carbon-14 Measurements of Marine Productivity
Authors: Smith Raymond C. , Baker Karen S.
Published: October 2006

The effects of increased ultraviolet radiation, due to decreased stratospheric ozone, on marine phytoplankton have been investigated with the use of static bottle in situ carbon-14 productivity measurements. The relative biological efficiency for photoinhibition may be used to calculate biologically effective doses and resultant amplification factors. The carbon-14 technique (short-term incubations) is inadequate for assessment of possible large amplification factor photoprocesses that may be ecologically significant.
Aircraft Gas Turbine Materials and Processes
Authors: Kear B. H. , Thompson E. R.
Published: October 2006

Materials and processing innovations that have been incorporated into the manufacture of critical components for high-performance aircraft gas turbine engines are described. The materials of interest are the nickel- and cobalt-base superalloys for turbine and burner sections of the engine, and titanium alloys and composites for compressor and fan sections of the engine. Advanced processing methods considered include directional solidification, hot isostatic pressing, superplastic forging, directional recrystallization, and diffusion brazing. Future trends in gas turbine technology are discussed in terms of materials availability, substitution, and further advances in air-cooled hardware.
Solar Wind Control of the Earth's Electric Field
Authors: Markson Ralph , Muir Michael
Published: October 2006

The sun-weather problem is placed within an electrical framework subject to experimental investigation. An explanation is suggested for how solar variability modulates the earth's electric field. The solar wind velocity is inversely correlated with the electrical potential of the ionosphere, a measure of the overall intensity of the earth's fair-weather atmospheric electric field. In seeking a physical cause of this relationship, galactic cosmic radiation was studied and it was also found to be inversely correlated with solar wind velocity. Thus, the earth's electric field intensity which is maintained by worldwide thunderstorm currents—a meteorological phenomenon—varies in phase with cosmic radiation. Since cosmic radiation is the primary source of atmospheric ionization, these findings support a proposed mechanism in which solar control of ionizing radiation modulates atmospheric electrification and thus possibly cloud physical processes. If the latter occurred, atmospheric energetics would be affected. Sun-weather research need no longer only consist of statistical correlations; an experimental approach is described. Establishment of a proposed geoelectric index would add a new dimension to solar-terrestrial studies.
Industrial Research in America: Challenge of a New Synthesis
Authors: David Edward E.
Published: October 2006

Industrial research in America faces a new era. Success will depend on a synthesis utilizing the strengths of industry, government, and academia to achieve industrial innovation. The origins of U.S. industrial research in the 19th century have led to its current traditions and philosophy. Vigorous, diverse, animated by both basic scientific knowledge and empirical techniques, it is today channeled by both societal needs and new technical possibilities. Many of its efforts involve fundamental research. Meeting future expectations will require even broader science, much of it from academia, as well as a license to function from governments and society.
Water Revisited
Authors: Stillinger Frank H.
Published: October 2006

Liquid water consists of a macroscopically connected, random network of hydrogen bonds, with frequent strained and broken bonds, that is continually undergoing topological reformation. Anomalous properties of water arise from the competition between relatively bulky ways of connecting molecules into local patterns characterized by strong bonds and nearly tetrahedral angles and more compact arrangements characterized by more strain and bond breakage. However, these alternatives constitute virtually a continuum of architectural possibilities rather than a discrete pair of options. The singular behavior of supercooled water near –45°C and the "hydrophobic" attraction between nonpolar entities are due to the same underlying phenomenon, namely, the clumping tendency of relatively strain-free convex cages or polyhedra.
Origin of the Warped Heliospheric Current Sheet
Authors: Wilcox J. M. , Hoeksema J. T. , Scherrer P. H.
Published: October 2006

The warped heliospheric current sheet for early 1976 is calculated from the observed photospheric magnetic field by a potential field method. Comparisons with measurements of the interplanetary magnetic field polarity for early 1976 obtained at several locations in the heliosphere by Helios 1, Helios 2, Pioneer 11, and at the earth show a rather detailed agreement between the computed current sheet and the observations. It appears that the large-scale structure of the warped heliospheric current sheet is determined by the structure of the photospheric magnetic field and that "ballerina skirt" effects may add small-scale ripples.
Sulfur Dioxide Emissions from La Soufriere Volcano, St. Vincent, West Indies
Authors: Hoff R. M. , Gallant A. J.
Published: October 2006

During the steady-state period of activity of La Soufriere Volcano in 1979, the mass emissions of sulfur dioxide into the troposphere amounted to a mean value of 339 ± 126 metric tons per day. This value is similar to the sulfur dioxide emissions of other Central American volcanoes but less than those measured at Mount Etna, an exceptionally strong volcanic source of sulfur dioxide.
The War Against Blue Mold
Authors: Lucas G. B.
Published: October 2006

An epidemic of blue mold of tobacco unexpectedly attacked crops in the United States and Canada in 1979, causing an estimated loss of almost a quarter billion dollars. The disease, caused by a fungus, apparently started in Cuba where half the crop was destroyed in 1979 and 90 percent in 1980. Control of blue mold is difficult and expensive. Resistant cultivars become susceptible within a few years. A therapeutic fungicide, metalaxyl, gives efficient control, but resistant strains of the fungus may soon appear. Blue mold is an international problem that will require the collaboration of scientists, governments, and Industries for an adequate solution.
Multidimensional Scaling, Tree-Fitting, and Clustering
Authors: Shepard Roger N.
Published: October 2006

American mathematical psychologists have developed computer-based methods for constructing representations of the psychological structure of a set of stimuli on the basis of pairwise measures of similarity or confusability. Applications to perceptual and semantic data illustrate how complementary aspects of the underlying psychological structure are revealed by different types of representations, including multidimensional spatial configurations and nondimensional tree-structures or clusterings.
Calcite-Impregnated Defluidization Structures in Littoral Sands of Mono Lake, California
Authors: Cloud Preston , Lajoie Kenneth R.
Published: October 2006

Associated locally with well-known tufa mounds and towers of Mono Lake, California, are subvertical, concretionary sand structures through which fresh calcium-containing artesian waters moved up to sites of calcium carbonate precipitation beneath and adjacent to the lake. The structures include closely spaced calcite-impregnated columns, tubes, and other configurations with subcylindrical to bizarre cross sections and predominantly vertical orientation in coarse, barely coherent pumice sands along the south shore of the lake. Many structures terminate upward in extensive calcareous layers of caliche and tufa. Locally they enter the bases of tufa mounds and towers. A common form superficially resembles root casts and animal burrows except that branching is mostly up instead of down. Similar defluidization structures in ancient sedimentary rocks have been mistakenly interpreted as fossil burrows.
Optimal Behavior: Can Foragers Balance Two Conflicting Demands?
Authors: Sih Andrew
Published: October 2006

According to much current theory, organisms should be able to balance the conflicting demands of the need to feed efficiently and the need to avoid predators while feeding. In an experimental conflict situation, it was possible to evaluate the relative fitnesses associated with the available choices and to compare the observed behaviors with predictions derived from fitness considerations. A backswimmer,
Notonecta hoffmanni
, was capable of balancing these two conflicting factors adaptively.
Solar Tracking by Plants
Authors: Ehleringer James , Forseth Irwin
Published: October 2006

Leaves of many desert and agricultural species have the ability to move diurnally, orienting perpendicular or parallel to the sun's direct rays. This phenomenon is widespread in many plant families and occurs in both C
3
and C
4
photosynthetic pathway plants. In the annual flora of desert communities, solar tracking becomes more frequent as the length of the growing season decreases. Leaves that are perpendicular to the sun's direct rays for tracking appear to have high photosynthetic rates throughout the day, whereas leaves parallel to the sun's rays have reduced leaf temperatures and transpirational water losses.
Fluoride Distribution and Biological Availability in the Fallout from Mount St. Helens, 18 to 21 May 1980
Authors: Taves Donald R.
Published: October 2006

Concentrations of fluoride in the ash fallout in central Washington from the 18 May 1980 eruption of Mount St. Helens varied severalfold, but none are high enough to constitute any immediate hazard to animal life. The heaviest fallout (Moses Lake) contained 113 parts per million (ppm) of acid-labile fluoride, but of this only 11 ppm was water-soluble and 20 ppm was available to rats. The fluoride concentrations in the urine of cattle feeding for 4 days on hay contaminated with this ash were essentially normal. Samples of ash from other areas generally had higher concentrations of acid-labile fluoride but lower concentrations of water-soluble fluoride. The concentration of water-soluble fluoride was inversely correlated with the coarseness of the fallout.
Early Proterozoic Microfossils and Penecontemporaneous Quartz Cementation in the Sokoman Iron Formation, Canada
Authors: Knoll Andrew H. , Simonson Bruce
Published: October 2006

Early Proterozoic microfossils from the Sokoman Iron Formation, northeastern Canada, are indistinguishable from those of the Gunflint Formation in both morphology and inferred community structure. The contemporaneity of the Sokoman assemblage with the Bitter Springs-like cyanobacteria of the Belcher Supergroup indicates that differences between the two major types of early Proterozoic microbiotas are primarily ecological and not temporal (evolutionary) in nature. In arenaceous iron formations, microfossils are restricted to peloids and are absent from pore-filling silica interpreted as cement. Cemented arenaceous intraclasts indicate that some of the silica was penecontemporaneous, and the abundance of minus-cement porosity in arenaceous iron formations demonstrates that early (pre-compaction) cementation was common.
Submillimeter Heterodyne Detection of Interstellar Carbon Monoxide at 434 Micrometers
Authors: Fetterman H. R. , Koepf G. A. , Goldsmith P. F. , Clifton B. J. , Buhl D. , Erickson N. R. , Peck D. D. , McAvoy N. , Tannenwald P. E.
Published: October 2006

A submillimeter heterodyne radiometer, developed for astronomical applications, uses an optically pumped laser local oscillator and a quasi-optical Schottky diode mixer. The resultant telescope-mounted system, which has a noise temperature less than 4000 K (double sideband) and high frequency and spatial resolution, has been used to detect the
J
= 6 → 5 rotational transition of carbon monoxide at 434 micrometers in the Orion molecular cloud. The measurements, when compared with previous millimeter-wave data, indicate that the broad carbon monoxide emission feature is produced by an optically thin gas whose temperature exceeds 180 K.
Geomorphology and Sediment Stability of a Segment of the U.S. Continental Slope off New Jersey
Authors: Robb James M. , Hampson John C. , Twichell David C.
Published: October 2006

The morphology of complex deposits of Pleistocene sediments covering the upper continental slope between Lindenkohl Canyon and South Toms Canyon results from both depositional and erosional processes. Small slump or slide features were detected primarily on the flanks of canyons or valleys and were observed to occur only within Pleistocene-aged sediments. Eocene to Miocene sediments are exposed over much of the mid- and lower slope in this area.
Textural and Crystal-Fabric Anisotropies and the Flow of Ice Masses
Authors: Baker Robert W.
Published: October 2006

Accurate modeling and prediction of glacier response requires a better understanding of the influence of physical anisotropies on creep. To investigate the effects of variations in the degree of preferred crystallographic orientation and ice crystal size on creep, 19 samples of anisotropic glacier ice were deformed in simple shear. Results indicate that the time required for ice samples to reach the minimum strain rate decreases as crystal size increases; an increase in crystal-fabric development from an isotropic fabric to one with a strong single maximum results in an enhancement of the minimum strain rate by a factor of 4; and a doubling of the crystal size results in about a ninefold increase in the minimum strain rate.
An Ice-Free Cretaceous? Results from Climate Model Simulations
Authors: Barron Eric J. , Thompson Starley L. , Schneider Stephen H.
Published: October 2006

We have quantitatively investigated the mechanisms that could explain the warm, equable climate that is believed to have been typical of the mid-Cretaceous (100 million years ago). By performing simulations with a climate model based on zonal energy balance, we demonstrate that past changes in geography were important in bringing about climatic change. However, the meridional distribution of Cretaceous temperatures cannot be successfully simulated unless additional physical "feedback mechanisms" are included in the model. These mechanisms may involve cloud and meridional heat transport changes. We also conclude that paleoclimatologists should reexamine carefully both existing data and their interpretations with regard to reconstruction of Cretaceous tropical and polar surface temperatures.
Evidence for Endomycorrhizae in Pennsylvanian Age Plant Fossils
Authors: Wagner Cynthia A. , Taylor Thomas N.
Published: October 2006

Fossil fungal chlamydospores from the tissues of a number of Pennsylvanian age fossil plants are described. Features such as size, shape, wall organization, and the structure of the subtending hyphal stalk suggest affinities with the modern endomycorrhizal fungus
Glomus
.
Zooplankton Fecal Pellets Link Fossil Fuel and Phosphate Deposits
Authors: Porter Karen Glaus , Robbins Eleanora Iberall
Published: October 2006

Fossil zooplankton fecal pellets found in thinly bedded marine and lacustrine black shales associated with phosphate, oil, and coal deposits, link the deposition of organic matter and biologically associated minerals with planktonic ecosystems. The black shales were probably formed in the anoxic basins of coastal marine waters, inland seas, and rift valley lakes where high productivity was supported by runoff, upwelling, and outwelling.
Eastern Indian 3800-Million-Year-Old Crust and Early Mantle Differentiation
Authors: Basu A. R. , Ray S. L. , Saha A. K. , Sarkar S. N.
Published: October 2006

Samarium-neodymium data for nine granitic and tonalite gneisses occurring as remnants within the Singhbhum granite batholith in eastern India define an isochron of age 3775 ± 89 × 106years with an initial143Nd/144Nd ratio of 0.50798 ± 0.00007. This age contrasts with the rubidium-strontium age of 3200 × 106years for the same suite of rocks. On the basis of the new samarium-neodynium data, field data, and petrologic data, a scheme of evolution is proposed for the Archean crust in eastern India. The isotopic data provide evidence that parts of the earth's mantle were already differentiated with respect to the chondritic samarium-neodymium ratio 3800 × 106years ago.
Ancient Suture Zones Within Continents
Authors: Moores E. M.
Published: October 2006

Ancient suture belts within continents are deformed regions which contain the remnants of former ocean basins. They form when two continents or island arcs that earlier were separated by an ocean basin converge and collide during plate tectonic activity. These belts provide the only record we have of deep oceanic crust and of ancient sea-floor processes for the first 94 percent of the earth's history, that is, prior to the oldest preserved crust in the oceans. Ten criteria for the recognition and interpretation of these ancient belts are discussed. A comprehensive program for the study of these belts should have great scientific and economic benefit for the United States and would be relatively cheap compared to other large national scientific efforts.
Continental Accretion: From Oceanic Plateaus to Allochthonous Terranes
Authors: Ben-Avraham Z. , Nur A. , Jones D. , Cox A.
Published: October 2006

Some of the regions of the anomalously high sea-floor topography in today's oceans may be modern allochthonous terranes moving with their oceanic plates. Fated to collide with and be accreted to adjacent continents, they may create complex volcanism, cut off and trap oceanic crust, and cause orogenic deformation. The accretion of plateaus during subduction of oceanic plates may be responsible for mountain building comparable to that produced by the collision of continents.
Climate Impact of Increasing Atmospheric Carbon Dioxide
Authors: Hansen J. , Johnson D. , Lacis A. , Lebedeff S. , Lee P. , Rind D. , Russell G.
Published: October 2006

The global temperature rose by 0.2°C between the middle 1960's and 1980, yielding a warming of 0.4°C in the past century. This temperature increase is consistent with the calculated greenhouse effect due to measured increases of atmospheric carbon dioxide. Variations of volcanic aerosols and possibly solar luminosity appear to be primary causes of observed fluctuations about the mean trend of increasing temperature. It is shown that the anthropogenic carbon dioxide warming should emerge from the noise level of natural climate variability by the end of the century, and there is a high probability of warming in the 1980's. Potential effects on climate in the 21st century include the creation of drought-prone regions in North America and central Asia as part of a shifting of climatic zones, erosion of the West Antarctic ice sheet with a consequent worldwide rise in sea level, and opening of the fabled Northwest Passage.
Social Complexity in Chinese Coastal Neolithic Sites
Authors: Pearson Richard
Published: October 2006

Neolithic cemeteries in Zhejiang, Jiangsu, and Shandong provinces from about 5000 to 2000 B.C. show increases in the mean numbers of burial goods, goods found with males, and tools used as grave goods; separation of burial localities; differentiation of sets of tools found with males and females; a decrease in goods found with children; and common ornaments found with males and females. The distribution of tools seems to reflect a sexual division, with an increase in the prominence of males which may be associated with intensification of cultivation. Emergence of ranking is suggested by very rich graves and ornaments shared by males and females. Chinese theories of cultural evolution are introduced.
Oxygen-18 Enrichment of Planktonic Foraminifera Due to Gametogenic Calcification Below the Euphotic Zone
Authors: Blanc Paul-Louis , Bé Allan W. H.
Published: October 2006

Empty shells of spinose planktonic foraminifera on the seabed are significantly enriched in oxygen-18 as compared with the shells of their living counterparts in surface waters. This enrichment is due to gametogenic calcification, which extracts calcium carbonate from deeper and colder waters as the shell sinks below the euphotic zone.
Intense Natural Selection in a Population of Darwin's Finches (Geospizinae) in the Galápagos
Authors: Boag Peter T. , Grant Peter R.
Published: October 2006

Survival of Darwin's finches through a drought on Daphne Major Island was nonrandom. Large birds, especially males with large beaks, survived best because they were able to crack the large and hard seeds that predominated in the drought. Selection intensities, calculated by O'Donald's method, are the highest yet recorded for a vertebrate population.
X-ray Absorption Spectroscopic Investigation of Trace Vanadium Sites in Coal
Authors: Maylotte D. H. , Wong J. , St. Peters R. L. , Lytle F. W. , Greegor R. B.
Published: October 2006

X-ray absorption spectroscopy was used to probe the chemical and structural environment of vanadium in coal. It was found that vanadium exists in at least two environments, in both of which it was coordinated to oxygens. There was no evidence of vanadium in nitrogen (porphyrin) or sulfide environments. It was also found that the vanadium environments in the raw coal did not survive unchanged in a liquefaction process. These findings have implications for coal cleaning processes and for trace element release into the liquefaction process stream.
Polysaccharides in Soil Fabrics
Authors: Foster R. C.
Published: October 2006

Treatment of ultrathin sections of natural soil fabrics with heavy metal stains, specific for carbohydrates, showed that polysaccharides are widely distributed in soils. In addition to being associated with living cells and dead remains of plants and microbes, carbohydrates also coat clay platelets and occur in crevices of submicron size within mineral aggregates. The determination of the precise location of polysaccharides in soils explains in part why some carbohydrates are resistant to microbial degradation and why small quantities of microbial polysaccharides are able to stabilize clay aggregates.
An Iridium Abundance Anomaly at the Palynological Cretaceous-Tertiary Boundary in Northern New Mexico
Authors: Orth Charles J. , Gilmore James S. , Knight Jere D. , Pillmore Charles L. , Tschudy Robert H. , Fassett James E.
Published: October 2006

An iridium abundance anomaly, with concentrations up to 5000 parts per trillion over a background level of 4 to 20 parts per trillion, has been located in sedimentary rocks laid down under freshwater swamp conditions in the Raton Basin of northeastern New Mexico. The anomaly occurs at the base of a coal bed, at the same stratigraphic position at which several well-known species of Cretaceous-age pollen became extinct.
Play Behavior: Persistence, Decrease, and Energetic Compensation During Food Shortage in Deer Fawns
Authors: Muller-Schwarze Dietland , Stagge Barbara , Muller-Schwarze Christine
Published: October 2006

White-tailed deer fawns continued to play despite an experimentally induced 33 percent milk shortage. They reduced play by 35 percent and general activity by 9 percent but increased grazing by 62 percent, resulting in virtually complete energetic compensation. This demonstrates the importance of play behavior in a mammal's activity budget.
Biological Control of Chestnut Blight
Authors: Anagnostakis Sandra L.
Published: October 2006

After 77 years of being attacked by the chestnut blight fungus, American chestnut trees continue to sprout from gradually declining root systems. The blight fungus in Italy is now associated with virus-like agents that limit its pathogenicity, and attempts have been made to introduce these controlling agents into the blight fungus in the United States. If a way can be found to help the spread here of strains of the fungus with controlling agents, it may be possible to save the American chestnut trees in our eastern forests.
Endolithic Microorganisms in the Antarctic Cold Desert
Authors: Friedmann E. Imre
Published: October 2006

In the frigid desert of the Antarctic dry valleys there are no visible life forms on the surface of the soil or rocks. Yet in certain rock types a narrow subsurface zone has a favorable microclimate and is colonized by microorganisms. Dominant are lichens of unusual organization. They survive not by physiological adaptation to lower temperatures, but by changing their mode of growth, being able to grow between the crystals of porous rocks. Their activity results in mobilization of iron compounds and in rock weathering with a characteristic pattern of exfoliation. This simple ecosystem lacks both higher consumers and predators.
Mammalian Evolution and the Great American Interchange
Authors: Marshall Larry G. , Webb S. David , Sepkoski J. John , Raup David M.
Published: October 2006

A reciprocal and apparently symmetrical interchange of land mammals between North and South America began about 3 million years ago, after the appearance of the Panamanian land bridge. The number of families of land mammals in South America rose from 32 before the interchange to 39 after it began, and then back to 35 at present. An equivalent number of families experienced a comparable rise and decline in North America during the same interval. These changes in diversity are predicted by the MacArthur-Wilson species equilibrium theory. The greater number of North American genera (24) initially entering South America than the reverse (12) is predicted by the proportions of reservoir genera on the two continents. However, a later imbalance caused by secondary immigrants (those which evolved from initial immigrants) is not expected from equilibrium theory.
The Columbia River Basalts
Authors: Hooper Peter R.
Published: October 2006

Between 17 million and 6 million years ago, 200,000 square kilometers of the American Northwest were flooded by basaltic lava that erupted through fissures in the crust up to 150 kilometers long. Larger individual eruptions covered over a third of the Columbia Plateau in a few days. The lavas represent partial melts of the earth's mantle that were only slightly modified by near-surface, upper crustal processes. The abundant chemical and mineralogical data now available offer an opportunity to study mantle composition and the processes involved in the evolution of the earth's crust.
Mass Extinctions in the Marine Fossil Record
Authors: Raup David M. , Sepkoski J. John
Published: October 2006

A new compilation of fossil data on invertebrate and vertebrate families indicates that four mass extinctions in the marine realm are statistically distinct from background extinction levels. These four occurred late in the Ordovician, Permian, Triassic, and Cretaceous periods. A fifth extinction event in the Devonian stands out from the background but is not statistically significant in these data. Background extinction rates appear to have declined since Cambrian time, which is consistent with the prediction that optimization of fitness should increase through evolutionary time.
Area-Perimeter Relation for Rain and Cloud Areas
Authors: Lovejoy S.
Published: October 2006

Following Mandelbrot's theory of fractals, the area-perimeter relation is used to investigate the geometry of satellite- and radar-determined cloud and rain areas between 1 and 1.2 × 10
6
square kilometers. The data are well fit by a formula in which the perimeter is given approximately by the square root of the area raised to the power D (
P
∼ √
A

D

), where D is interpreted as the fractal dimension of the perimeter. It is concluded that rain and cloud perimeters are fractals—they have no characteristic horizontal length scale between 1 and 1000 kilometers.
Iridium Anomaly Approximately Synchronous with Terminal Eocene Extinctions
Authors: Alvarez Walter , Asaro Frank , Michel Helen V. , Alvarez Luis W.
Published: October 2006

An iridium anomaly has been found in coincidence with the known microtektite level in cores from Deep Sea Drilling Project site 149 in the Caribbean Sea. The iridium was probably not in the microtektites but deposited simultaneously with them; this could occur if the iridium was deposited from a dust cloud resulting from a bolide impact, as suggested for the anomaly associated with the Cretaceous-Tertiary boundary. Other workers have deduced that the microtektites are part of the North American strewn tektite field, which is dated at about 34 million years before present, and that the microtektite horizon in deep-sea cores is synchronous with the extinction of five radiolarian species. Mass extinctions also occur in terrestrial mammals within 4 million years of this time. The iridium anomaly and the tektites and microtektites are supportive of a major bolide impact about 34 million years ago.
Airborne Lidar Measurements of the Soufriere Eruption of 17 April 1979
Authors: Fuller W. H. , Sokol S. , Hunt W. H.
Published: October 2006

At the time of the Soufriere, St. Vincent, volcanic eruption of 17 April 1979, a NASA P-3 aircraft with an uplooking lidar (light detection and ranging) system onboard was airborne 130 kilometers east of the island. Lidar measurements of the fresh volcanic ash were made approximately 2 hours after the eruption, 120 kilometers to the northeast and east. On the evening of 18 April, the airborne lidar, on a southerly flight track, detected significant amounts of stratospheric material in layers at 16, 17, 18, and 19.5 kilometers. These data, and measurements to the north on 19 April, indicate that the volcanic plume penetrated the stratosphere to an altitude of about 20 kilometers and moved south during the first 48 hours after the eruption.
Calcium Carbonate Hexahydrate from Organic-Rich Sediments of the Antarctic Shelf: Precursors of Glendonites
Authors: Suess E. , Balzer W. , Hesse K.-F. , Müller P. J. , Ungerer C. A. , Wefer G.
Published: October 2006

Large euhedral crystals of calcium carbonate hexahydrate were recovered from a shelf basin of the Bransfield Strait, Antarctic Peninsula, at a water depth of 1950 meters and sub-zero bottom water temperatures. The chemistry, mineralogy, and stable isotope composition of this hydrated calcium carbonate phase, its environment of formation, and its mode of precipitation confirm the properties variously attributed to hypothetical precursors of the glendonites and thereby greatly expand their use in paleoceanographic interpretation.
Sex Pheromone of the Winter Moth, a Geometrid with Unusually Low Temperature Precopulatory Responses
Authors: Roelofs W. L. , Hill A. S. , Linn C. E. , Meinwald J. , Jain S. C. , Herbert H. J. , Smith R. F.
Published: October 2006

The sex pheromone for the winter moth,
Operophtera brumata
(L.), has been identified as the novel compound (
Z
,
Z
,
Z
)-1,3,6,9-nonadecatetraene. The male moths respond to the pheromone at low temperatures (4° to 15°C) and exhibit an upper response limit that coincides with the lower response limit for other reported moth sex pheromone systems. The pheromone attracted two other geometrid species,
O. bruceata
(Bruce spanworm) and
O. occidentalis
.
Retroviral DNA Integration Directed by HIV Integration Protein in Vitro
Authors: Bushman Frederic D. , Fujiwara Tamio , Craigie Robert
Published: October 2006

Efficient retroviral growth requires integration of a DNA copy of the viral RNA genome into a chromosome of the host. As a first step in analyzing the mechanism of integration of human immunodeficiency virus (HIV) DNA, a cell-free system was established that models the integration reaction. The in vitro system depends on the HIV integration (IN) protein, which was partially purified from insect cells engineered to express IN protein in large quantities. Integration was detected in a biological assay that scores the insertion of a linear DNA containing HIV terminal sequences into a λ DNA target. Some integration products generated in this assay contained five-base pair duplications of the target DNA at the recombination junctions, a characteristic of HIV integration in vivo; the remaining products contained aberrant junctional sequences that may have been produced in a variation of the normal reaction. These results indicate that HIV IN protein is the only viral protein required to insert model HIV DNA sequences into a target DNA in vitro.
Seasonality and Interaction of Biogenic and Lithogenic Particulate Flux at the Panama Basin
Authors: Honjo Susumu
Published: October 2006

Time-series sediment traps were deployed for an entire year at three depths (890, 2590, and 3560 meters) at a deepwater station (3860 meters) in the Panama Basin. The amount of horizontal and lithogenic particulate material arriving at the three depths was seasonally pulsed and directly reflected changes in surface primary production. Two spikes of organic flux were simultaneously recorded at all three depths: (i) a period of high productivity during regional upwelling in February through March and (ii) an unusual bloom of a single species of coccolithophorid during June through July. This latter spike delivered approximately 25 grams of coccolith per square meter of area at a depth of 3860 meters during less than 60 days. The flux of lithogenic particles increased with increasing depth and was seasonally correlated to surface production and current direction, and not to the detritus discharged in river flow. The data suggest that suspended clays are efficiently scavenged from the water column by rapidly sinking organic aggregates.
Mineral Identification from Orbit: Initial Results from the Shuttle Multispectral Infrared Radiometer
Authors: Goetz Alexander F. H. , Rowan Lawrence C. , Kingston Marguerite J.
Published: October 2006

A shuttle-borne radiometer containing ten channels in the reflective infrared has demonstrated that direct identification of carbonates and hydroxyl-bearing minerals is possible by remote measurement from Earth orbit.
Carbon Monoxide Measurements in the Troposphere
Authors: Reichle Henry G. , Beck Sherwin M. , Haynes Ray E. , Hesketh Wilfred D. , Holland J. Alvin , Hypes Warren D. , Orr Harry D. , Sherrill Robert T. , Wallio H. Andrew , Casas Joseph C. , Saylor Mary S. , Gormsen Barbara B.
Published: October 2006

During the second flight of the space shuttle, the measurement of air pollution from satellites (MAPS) experiment in the OSTA-1 payload acquired approximately 35 hours of radiometric measurements of the carbon monoxide mixing ratio in the middle troposphere, upper troposphere, and lower stratosphere. A gas filter radiometer operating in the 4.67-micrometer band was used to acquire the data over the region from 38°N to 38°S during both daytime and nighttime. The performance of the measurement system was excellent. The data reduced to date indicate the presence of significant gradients in the middle tropospheric carbon monoxide mixing ratio with both latitude and longitude over the North Atlantic, the Mediterranean Sea, and the Middle East. On the basis of comparisons with directly measured values, the accuracy of the measurements is approximately 15 percent. Comparisons of data taken on successive orbits over the same geographic region indicate that the repeatability of the measurements is approximately 5 percent.
The Role of Inheritance in Behavior
Authors: Plomin Robert
Published: October 2006

Inheritance plays a major role in behavior as shown by selection and strain studies for animal behavior and by twin and adoption studies for human behavior. Unlike simple Mendelian characteristics, genetic variance for behavioral dimensions and disorders rarely accounts for more than half of the phenotypic variance, and multiple genes with small effects appear to be involved rather than one or two major genes. Genetic research on behavior will be transformed by techniques of molecular biology that can be used to identify DNA sequences responsible for behavioral variation. However, the importance of nongenetic factors and the multigenetic control of behavior require new strategies to detect DNA markers that account for small amounts of behavioral variation.
HSP104 Required for Induced Thermotolerance
Authors: Sanchez Yolanda , Lindquist Susan L.
Published: October 2006

A heat shock protein gene,
HSP104
, was isolated from
Saccharomyces cerevisiae
and a deletion mutation was introduced into yeast cells. Mutant cells grew at the same rate as wild-type cells and died at the same rate when exposed directly to high temperatures. However, when given a mild pre-heat treatment, the mutant cells did not acquire tolerance to heat, as did wild-type cells. Transformation with the wild-type gene rescued the defect of mutant cells. The results demonstrate that a particular heat shock protein plays a critical role in cell survival at extreme temperatures.
Synchronized Moulting Controlled by Communication in Group-Living Collembola
Authors: Leinaas Hans Petter
Published: October 2006

Group-living Collembola of the genus
Hypogastrura
coordinate their moulting by communication. Animals of different ages and moulting rhythms synchronized the moulting rhythms when combined in a single culture. This synchronization is apparently not dependent on external stimuli but is coordinated by chemical communication among these insects.
Industrial Innovation Policy: Lessons from American History
Authors: Nelson Richard R. , Langlois Richard N.
Published: October 2006

The historical interrelations of government support of R & D and technical change in seven major American industries point to three types of policy that have been successful in the past: (i) government R & D support for technologies in which the government has a strong and direct procurement interest; (ii) decentralized systems of government-supported research in the "generic" area between the basic and the applied; and (iii) a decentralized system of clientele-oriented support for applied R & D. A fourth type of policy, under which the government attempts to "pick winners" in commercial applied R & D, has been a clear-cut failure.
Atmospheric Dispersion of Vapors: Are Molecular Properties Unimportant?
Authors: Glotfelty D. E. , Taylor A. W. , Zoller W. H.
Published: October 2006

Vapor profiles of pesticide mixtures over fallow agricultural fields reveal consistent rapid shifts in the relative proportions of the components in air. These relative concentration changes are correlated with molecular weight and size and reveal a significant molecular contribution to dispersion in turbulent air. Atmospheric studies that rely upon tracer gases, or use calculations that assume the equality of eddy dispersion coefficients, may be in serious error.
Abyssal Water Carbon-14 Distribution and the Age of the World Oceans
Authors: Stuiver Minze , Quay Paul D. , Ostlund H. G.
Published: October 2006

The carbon-14 distribution in the abyssal waters of the world oceans indicates replacement times for Pacific, Indian, and Atlantic ocean deep waters (more than 1500 meters deep) of approximately 510, 250, and 275 years, respectively. The deep waters of the entire world ocean are replaced on average every 500 years.
Shift Work Among Dual-Earner Couples with Children
Authors: Presser Harriet B. , Cain Virginia S.
Published: October 2006

In a 1980 sample of U.S. nonfarm households with children and with both spouses employed full time, one-third of the couples included at least one spouse who worked other than a regular day shift. In about one-tenth of the couples the spouses worked entirely different shifts with no overlap in hours. These findings are linked to an earlier study which showed a high prevalence of child care by employed fathers whose wives were employed in certain occupations.
Virus Infection of Culturable
Chlorella
-Like Algae and Development of a Plaque Assay
Authors: Van Etten James L. , Burbank Dwight E. , Kuczmarski Daniel , Meints Russel H.
Published: October 2006

Four distinct viruses with double-stranded DNA are known to replicate in
Chlorella
-like algae symbiotic with hydras and paramecia. An attempt was made to infect a number of cultured
Chlorella
strains derived from invertebrate hosts with these viruses. One of the viruses, PBCV-1, replicated in two of the algal strains. Restriction endonuclease analysis of the viral DNA showed that the infectious progeny virus was identical to the input virus; thus, Koch's postulates were fulfilled. Viral infection of the two
Chlorella
strains has allowed the large-scale production of a eukaryotic algal virus and the development of a plaque assay for the virus.
Cavitands: Organic Hosts with Enforced Cavities
Authors: Cram Donald J.
Published: October 2006

Organic hosts are now being designed and synthesized which contain enforced cavities large enough to complex and even surround simple inorganic or organic guest compounds.
Growth Enhancement of Plants by Femtomole Doses of Colloidally Dispersed Triacontanol
Authors: Laughlin R. G. , Munyon R. L. , Ries S. K. , Wert V. F.
Published: October 2006

Colloidal dispersions of crystalline 1-triacontanol in water, upon foliar application to corn (
Zea mays
L.) seedlings, resulted in growth increases at femtomole dosages (spray concentrations as low as 1 nanogram per cubic decimeter). The maximum growth increase occurred at 100 nanograms per cubic decimeter; at both higher and lower concentrations lessened growth increase was observed. The dispersions were prepared by sonication, with control of temperature and composition. Selected surfactants, which facilitate the dispersion process, are effective at 1 percent of the 1-triacontanol composition and are nontoxic.
Residential Firewood Use in the United States
Authors: Lipfert Frederick W. , Dungan Jennifer L.
Published: October 2006

An empirical relation between residential firewood use and population density was developed from survey data for 64 counties in New England and was corroborated by data from other states. The results indicate that usage is concentrated in urbanized areas of the Northeast and north central states and that about 9.0 to 11.0 percent of U.S. space heating input is from firewood. No constraints due to the supply of wood were apparent in 1978-1979. These findings have implications for effects on air quality.
The Developing Technology of Gas Separating Membranes
Authors: Henis Jay M. S. , Tripodi Mary K.
Published: October 2006

The background of and commercial needs leading to the development of practical membrane systems for the separation of industrial gases are presented. The critical issues and fundamental technical limitations that delayed earlier development of such systems and the solutions of some of the major problems in the field are discussed. Particular attention is given to the methods by which high gas fluxes and high selectivities have been achieved in hollow fibers. The performance characteristics of various practical gas separation methods are compared, and the effects of parameters such as pressure and contaminant levels are illustrated with representative examples.
Asian Dust: Seasonal Transport to the Hawaiian Islands
Authors: Parrington Josef R. , Zoller William H. , Aras Namik K.
Published: October 2006

Analyses of atmospheric particles collected at Mauna Loa Observatory in Hawaii from February 1979 through September 1982 reveal strong influxes of Asian dust in the spring of each year. Concentrations of a typical crustal element, aluminum, are more than an order of magnitude greater between February and June than during the remainder of the year (71 ± 51 versus 6.7 ± 2.3 nanograms per cubic meter). The mass of crustal material transported during the relatively short dust episodes accounts for an average of 80 percent of the total yearly mass of atmospheric particles at 3400 meters on Mauna Loa.
Intercalated Clay Catalysts
Authors: Pinnavaia Thomas J.
Published: October 2006

Recent advances in the intercalation of metal complex cations in smectite clay minerals are leading to the development of new classes of selective heterogeneous catalysts. The selectivity of both metal-catalyzed and proton-catalyzed chemical conversions in clay intercalates can often be regulated by controlling surface chemical equilibria, interlamellar swelling, or reactant pair proximity in the interlayer regions. Also, the intercalation of polynuclear hydroxy metal cations and metal cluster cations in smectites affords new pillared clay catalysts with pore sizes that can be made larger than those of conventional zeolite catalysts.
Rapid Flow Cytometric Analysis of the Cell Cycle in Intact Plant Tissues
Authors: Galbraith David W. , Harkins Kristi R. , Maddox Joyce M. , Ayres Nicola M. , Sharma Dharam P. , Firoozabady Ebrahim
Published: October 2006

Mechanical chopping of plant tissues in the presence of mithramycin released intact nuclei representative of the cells within the tissues. The amount of nuclear DNA in the homogenates of monocotyledonous and dicotyledonous plants was accurately and rapidly determined by flow microfluorometry, and the distribution of nuclei involved in the cell cycle was charted for tissues selected from different physical locations or developmental stages.
Climatic Anomalies in the Tropical Pacific Ocean and Corn Yields in the United States
Authors: Handler Paul , Handler Ellen
Published: October 2006

The association between climatic anomalies in the tropical Pacific Ocean, often called El Niño events, and annual corn production in the United States was investigated. Temperature and atmospheric pressure in parts of the United States have been correlated with El Niño events. This research suggests that in years in which an El Niño event causes surface temperatures in the tropical Pacific to become warmer than normal, there is a higher probability of an above-average corn crop in the United States. For years when sea surface temperatures are average or cool, no significant association is observed.