bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetospheric Effects of Power Line Radiation
Authors: Park C. G. , Helliwell R. A.
Published: October 2006

Radiation from electrical power lines leaks into the magnetosphere and stimulates strong very-low-frequency wave activity out to many earth radii. Observations in Antarctica show that wave activity induced by power lines tends to occur during the daytime when power consumption is high in the source region in eastern Canada. The wave frequency ranges from 1 to 8 kilohertz. This man-made wave activity may have significant effects on energetic electrons trapped in the earth's radiation belts.
Photoinduced Nucleation of Water Vapor
Authors: Wen F. C. , McLaughlin Timothy , Katz Joseph L.
Published: October 2006

Strong photoinduced nucleation of pure water vapor was found to occur in a wavelength range where no ultraviolet absorption of water vapor has been reported. Systematic studies were made of the dependence of the nucleation rate and the delay time for the initiation of nucleation on light intensity. The results obtained were accurately fitted by a phenomenological mechanism whereby the nucleation is initiated by clusters accumulating an appropriate number of photoexcited water molecules.
Sexual Parasitism in the Green Tree Frog (
Hyla cinerea
)
Authors: Perrill Stephen A. , Gerhardt H. Carl , Daniel Richard
Published: October 2006

Noncalling adult male tree frogs were found in close association with about 16 percent of the calling males in a pond in Georgia. In 13 of 30 field experiments a noncalling satellite male intercepted and achieved amplexus with a gravid female moving toward the calling male. This mating strategy, which conserves energy required for calling, resembles the strategy employed by other vertebrates.
Oxygen Isotope Composition of Subglacially Precipitated Calcite: Possible Paleoclimatic Implications
Authors: Hanshaw Bruce B. , Hallet Bernard
Published: October 2006

Isotopic analyses of subglacially precipitated calcite from near a modern temperate glacier show that the δ
18
O (=
18
O/
16
O relative to standard mean ocean water) of the calcite records the δ
18
O of the ice from that glacier. It may therefore be possible to determine the δ
18
O of Pleistocene ice sheets on the basis of isotopic analyses of calcite formed under that ancient ice. This, in turn, would allow estimation of the δ
18
O of Pleistocene oceans and correction of the paleotemperature scale based on foraminiferal oxygen isotopic analyses.
Identification of aC-Glucuronide of Δ6-Tetrahydrocannabinol as a Mouse Liver Conjugate in vivo
Authors: Levy Shlomo , Yagen Boris , Mechoulam Raphael
Published: October 2006

Δ6-Tetrahydrocannabinol-C-4′-glucuronide was found in the livers of mice that had been administered Δ6-tetrahydrocannabinol. Thus,C-glucuronidation of a compound that contains a free hydroxyl group has been demonstrated in vivo.
Migration of Radioactive Wastes: Radionuclide Mobilization by Complexing Agents
Authors: Means Jeffrey L. , Crerar David A. , Duguid James O.
Published: October 2006

Ion exchange, gel filtration chromatography, and gas chromatography-mass spectrometry analyses have demonstrated that ethylenediaminetetraacetic acid (EDTA), an extremely strong complexing agent commonly used in decontamination operations at nuclear facilities, is causing the low-level migration of cobalt-60 from intermediate-level liquid waste disposal pits and trenches in the Oak Ridge National Laboratory burial grounds. Because it forms extremely strong complexes with rare earths and actinides, EDTA or similar chelates may also be contributing to the mobilization of these radionuclides from various terrestrial radioactive waste burial sites around the country.
Second Structural Motif for Recognition of DNA by Oligonucleotide-Directed Triple-Helix Formation
Authors: Beal Peter A. , Dervan Peter B.
Published: October 2006

Relative orientations of the DNA strands within a purine⋅purine⋅pyrimidine triple helix have been determined by affinity cleaving. A purine-rich oligonucleotide bound in the major groove of double-helical DNA antiparallel to the Watson-Crick purine strand. Binding depended upon the concentration of multivalent cations such as spermine or Mg
2+
, and appeared to be relatively independent of pH. Two models with specific hydrogen-bonding patterns for base triplets (G⋅GC, A⋅AT, and T⋅AT) are proposed to explain the sequence specificity of binding. The two models differ in the conformation about the glycosyl bond (syn or anti) and the location of the phosphate-deoxyribose backbone in the major groove of DNA. This motif broadens the structural frameworks available as a basis for the design of sequence-specific DNA binding molecules.
Noble Gases in the Murchison Meteorite: Possible Relics of
s
-Process Nucleosynthesis
Authors: Srinivasan B. , Anders Edward
Published: October 2006

The Murchison carbonaceous chondrite contains a new type of xenon component, enriched by up to 50 percent in five of the nine stable xenon isotopes, mass numbers 128 to 132. This component, comprising 5 × 10
-5
of the total xenon in the meteorite, is released at 1200° to 1600°C from a severely etched mineral fraction, and probably resides in some refractory mineral. Krypton shows a similar but smaller enrichment in the isotopes 80 and 82. Neon and helium released in the same interval also are quite anomalous, being highly enriched in the isotopes 22 and 3. These patterns are strongly suggestive of three nuclear processes believed to take place in red giants: the
s
process (neutron capture on a slow time scale), helium burning, and hydrogen shell burning. If this interpretation is correct, then primitive meteorites contain yet another kind of alien, presolar material: dust grains ejected from red giants.
Plant Chemistry and the Evolution of Host Specificity: New Evidence from
Heliconius
and
Passiflora
Authors: Smiley John
Published: October 2006

Larval growth rates of
Heliconius
butterflies do not closely parallel host plant choice, an indication that factors other than host plant chemistry are important in evolving host specificity. High growth rate in one species is correlated with reduction in number of palatable host species. This suggests a mechanism by which ecologically restricted species become progressively biochemically specialized.
Abscisic Acid Induces Formation of Floating Leaves in the Heterophyllous Aquatic Angiosperm
Potamogeton nodosus
Authors: Anderson Lars W. J.
Published: October 2006

Potamogeton nodosus
tubers produce floating-type instead of submersed-type leaves when exposed to 10
–5
molar synthetic abscisic acid. Abscisic acid-induced leaves have stomata on upper leaf surfaces and higher width/length ratios than controls. These effects are wholly or partially overcome by simultaneous exposure to abscisic acid combined with gibberellic acid, kinetin, or benzyladenine.
In Vitro and in Vivo Consequences of VLA-2 Expression on Rhabdomyosarcoma Cells
Authors: Chan Bosco M. C. , Matsuura Nariaki , Takada Yoshikazu , Zetter Bruce R. , Hemler Martin E.
Published: October 2006

Cloned integrin α
2
subunit complementary DNA was expressed on human rhabdomyosarcoma (RD) cells to give a functional VLA-2 (α
2
β
1
) adhesion receptor. The VLA-2-positive RDA2 cells not only showed increased adhesion to collagen and laminin in vitro, but also formed substantially more metastatic tumor colonies in nude mice after either intravenous or subcutaneous injection. These results show that a specific adhesion receptor (VLA-2) can markedly enhance both experimental and spontaneous metastasis. In contrast to the metastasis results, there was no difference in either the in vitro growth rate or apparent in vivo tumorigenicity of RD and RDA2 cells.
Energy and Labor in the Construction Sector
Authors: Hannon Bruce , Stein Richard G. , Segal B. Z. , Serber Diane
Published: October 2006

An energy input-output model was used to investigate energy and employment in the construction industry. The model covered nearly 400 industrial sectors and was used to determine the impact of construction activities on total national energy consumption in 1967 and to study the patterns of total energy use and employment within various construction categories. For the construction of new buildings, total energy consumption could be reduced by 20 percent by selecting less energy-intensive building materials and assemblies for fixed programmatic requirements, by expending energy in construction to minimize the total lifetime energy cost of buildings, and by energy conservation in industries that supply direct and indirect inputs to the construction sector of the economy.
Early Deglaciation of the Labrador Shelf
Authors: Vilks Gustavs , Mudie Peta J.
Published: October 2006

Two marine sediment cores from a basin on the southeastern Labrador Shelf penetrate a mud sequence extending back to 21,000 carbon-14 years before the present (B.P.). The benthic foraminifera are dominated by subartic nearshore species indicative of ice-free summer waters. The pollen record indicates the presence of a sedge-shrub tundra in eastern Labrador as early as 21,000 years B.P. Both sources of evidence suggest less extensive continental ice than has previously been reported for this subarctic region.
Social Plasticity in the Acorn Woodpecker
Authors: Stacey Peter B. , Bock Carl E.
Published: October 2006

Acorn woodpeckers (
Melanerpes formicivorus
) in southeastern Arizona exhibited two different types of social organization: one of highly cooperative and resident groups and another of birds that migrated and formed only temporary male-female pairs during reproduction. The occurrence of both patterns in the same population indicates a high degree of social flexibility in this species.
Assembly of Type C Oncornaviruses: A Model
Authors: Bolognesi D. P. , Montelaro R. C. , Frank H. , Schäfer W.
Published: October 2006

The salient features of this model for oncornavirus assembly are that uncleaved precursor molecules to the internal virus polypeptides possess specific recognition sites both for viral envelope constituents already inserted in the cell membrane and for the viral RNA. After orderly alignment of these components at the budding site, virus maturation proceeds through specific proteolytic cleavage of the precursor components and association of the resultant molecules into the characteristic type C virion substructures revealed by electron microscopy.
Pineal Serotonin
N
-Acetyltransferase Activity: Abrupt Decrease in Adenosine 3′,5′-Monophosphate May Be Signal for "Turnoff"
Authors: Klein D. C. , Buda M. J. , Kapoor C. L. , Krishna G.
Published: October 2006

Dispersed pinealocytes have been used to study the role of adenosine 3′,5′-monophosphate (cyclic AMP) in the "turnoff" of
N
-acetyltransferace activity. Activity was first stimulated 100-fold by treating cells with
l
-norepinephrine.
l
-Propranolol acted stereospecifically to rapidly reverse this, resulting in a 70 percent loss of enzyme activity within 15 minutes. An even more rapid
l
-propranolo
l
-induced decrease in cyclic AMP also occurred. This together with the observation that the inhibitory effect of
l
-propranolol on
N
-acetyltransferase was blocked by dibutyryl cyclic AMP and phosphodiesterase inhibitors indicate that an abrupt decrease in cyclic AMP may be the signal for the rapid decrease in pineal
N
-acetyltransferase activity.
Early Sedentary Economy in the Basin of Mexico
Authors: Niederberger Christine
Published: October 2006

Artifactual and nonartifactual evidence from the lacustrine shores of the Chalco-Xochimilco Basin suggest the existence of fully sedentary human communities in the Basin of Mexico from at least the sixth millennium B.C.
Zea diploperennis
(Gramineae): A New Teosinte from Mexico
Authors: Iltis Hugh H. , Doebley John F. , Guzmán M. Rafael , Pazy Batia
Published: October 2006

A perennial teosinte or "wild maize" endemic to the Cerro de San Miguel, Sierra de Manantlan, Jalisco, Mexico differs from
Zea perennis
by dimorphic rhizomes, robust habit, and a larger number of longer, laxer tassel branches. The fact that it is a diploid (2
n
= 20) has taxonomic and agronomic significance. The seeds are used locally for food.
Wax Secretion and Color Phases of the Desert Tenebrionid BeetleCryptoglossa verrucosa(LeConte)
Authors: Hadley Neil F.
Published: October 2006

The desert beetleCryptoglossa verrucosa(LeConte) exhibits distinct color phases that range from light blue to jet black when subjected to extremes of low and high humidity, respectively. The color phases are created by "wax filaments" that spread from the tips of miniature tubercles that cover the cuticle surface. The meshwork that accumulates at low humidity reduces transcuticular water loss and may lower the rate at which body temperature rises under a radiation load by increasing reflectance.
Circulation and Melting Beneath the Ross Ice Shelf
Authors: Jacobs Stanley S. , Gordon Arnold L. , Ardai J. L.
Published: October 2006

Thermohaline observations in the water column beneath the Ross Ice Shelf and along its terminal face show significant vertical stratification, active horizontal circulation, and net melting at the ice shelf base. Heat is supplied by seawater that moves southward beneath the ice shelf from a central warm core and from a western region of high salinity. The near-freezing Ice Shelf Water produced flows northward into the Ross Sea.
Io: An Intense Brightening Near 5 Micrometers
Authors: Witteborn F. C. , Bregman J. D. , Pollack J. B.
Published: October 2006

Spectrophotometric observations of the jovian satellite Io on 20 and 21 February 1978 (Universal Time) were made from 1.2 to 5.4 micrometers. Io's brightness at 4.7 to 5.4 micrometers was found to be three to five times greater at an orbital phase angle of 68° than at orbital phase angles of 23° (5.5 hours before the brightening) and 240° (20 hours after the brightening). Since the 5-micrometer albedo of Io is near unity under ordinary conditions, the observed transient phenomenon must have been the result of an emission mechanism. Although several such mechanisms were examined, the actual choice is not clear.
Superheavy Elements: A Crossroads
Authors: Seaborg G. T. , Loveland W. , Morrissey D. J.
Published: October 2006

The failure to synthesize superheavy elements by using complete fusion reactions is most likely understandable in terms of the low survival probabilities of the superheavy precursors formed in these reactions or (in some cases) the failure to achieve complete fusion. Further attempts to synthesize these elements by using complete fusion or deep inelastic transfer reactions, or both, are discussed in light of these results.
Venus Thermosphere and Exosphere: First Satellite Drag Measurements of an Extraterrestrial Atmosphere
Authors: Keating G. M. , Tolson R. H. , Hinson E. W.
Published: October 2006

Atmospheric drag measurements obtained from the study of the orbital decay of Pioneer Venus 1 indicate that atomic oxygen predominates in the Venus atmosphere above 160 kilometers. Drag measurements give evidence that conditions characteristic of a planetary thermosphere disappear near sundown, with inferred exospheric temperatures sharply dropping from approximately 300 K to less than 150 K. Observed densities are generally lower than given by theoretical models.
Venus Lower Atmospheric Composition: Analysis by Gas Chromatography
Authors: Oyama Vance I. , Carle Glenn C. , Woeller Fritz , Pollack James B.
Published: October 2006

The first gas chromatographic analysis of the lower atmosphere of Venus is reported. Three atmospheric samples were analyzed. The third of these samples showed carbon dioxide (96.4 percent), molecular nitrogen (3.41 percent), water vapor (0.135 percent), molecular oxygen [69.3 parts per million (ppm)], argon (18.6 ppm), neon (4.31 ppm), and sulfur dioxide (186 ppm). The amounts of water vapor and sulfur dioxide detected are roughly compatible with the requirements of greenhouse models of the high surface temperature of Venus. The large positive gradient of sulfur dioxide, molecular oxygen, and water vapor from the cloud tops to their bottoms, as implied by Earth-based observations and these results, gives added support for the presence of major quantities of aqueous sulfuric acid in the clouds. A comparison of the inventory of inert gases found in the atmospheres of Venus, Earth, and Mars suggests that these components are due to outgassing from the planetary interiors.
Anomalous Bottom Water South of the Grand Banks Suggests Turbidity Current Activity
Authors: Amos Anthony F. , Gerard Robert D.
Published: October 2006

Highly turbid bottom water at the margin of the Sohm Abyssal Plain was identified by its temperature, salinity, and oxygen content as originating upslope on the continental rise. The fact that the particulate concentrations were one to two orders of magnitude higher than are normally found in deep ocean waters suggests a turbidity current as the agent bringing this water downslope.
Observations of Hydrogen at Room Temperature (25°C) and High Pressure (to 500 Kilobars)
Authors: Mao H. K. , Bell P. M.
Published: October 2006

Hydrogen becomes a solid at 25°C when subjected to a pressure of 57 kilobars. The high-pressure phase appears as a transparent crystalline mass. The refractive index of the high-pressure phase increases sharply with pressure, indicating a density increase of similar magnitude. At 360 kilobars the calculated density of the high-pressure phase is 0.6 to 0.7 grams per cubic centimeter.
Ocean Floor Boundaries
Authors: Hedberg Hollis D.
Published: October 2006

The base of the continental slope, combined with the concepts of a boundary zone, a technical advisory boundary commission, and special treatment for restricted seas, offers a readily attainable, natural, practicable, and equitable boundary between national and international jurisdiction over the ocean floor. There is no point in bringing into the boundary formula the unnecessary added complication of thickness of sediments, as recently proposed. Review of the U.S. offshore brings out the critical importance with respect to energy resources of proper choice of boundary principles and proper determination of the base-of-continent line about our shores. The advice of the pertinent science and technology community should urgently be sought and contributed to decisions on offshore boundaries.
The Nature of Plant Species
Authors: Levin Donald A.
Published: October 2006

The species concept is a central tenet of biological diversity. Attempts to describe diversity have led to empirical concepts of species based on assumptions found wanting for plants. Plant species lack reality, cohesion, independence, and simple evolutionary or ecological roles. The concept of species for plant taxonomists and evolutionists can only serve as a tool for characterizing diversity in a mentally satisfying way. Diversity is idiosyncratic. It is impossible to reconcile idiosyncrasy with preconceived ideas of diversity. The search for hidden likenesses is unlikely to yield a unifying species concept. The concept that is most operational and utilitarian for plants is a mental abstraction which orders clusters of diversity in multidimensional character space.
2-Methyltetrahydrofuran—Lithium Hexafluoroarsenate: A Superior Electrolyte for the Secondary Lithium Electrode
Authors: Koch V. R. , Young J. H.
Published: October 2006

Rechargeable, high energy density lithium batteries require an efficient lithium electrode. Earlier work with electrolytes based on propylene carbonate, methyl acetate, and tetrahydrofuran yielded poor lithium electrode cycling efficiencies because of electrolyte reduction by lithium. Solutions of lithium hexafluoroarsenate in 2-methyltetrahydrofuran are found to be remarkably stable toward lithium, resulting in cycling efficiencies that approach 98 percent. The ability of 2-methyltetrahydrofuran to resist reduction by lithium is thought to be based on the position of its lowest unfilled molecular orbital relative to that of tetrahydrofuran.
Dual Actions of Substance P on Nociception: Possible Role of Endogenous Opioids
Authors: Frederickson Robert C. A. , Burgis V. , Harrell C. E. , Edwards J. D.
Published: October 2006

Substance P produces analgesia when administered to mice in very small doses by the intraventricular route (1.25 to 5 nanograms per mouse). The analgesic effect can be blocked by naloxone. At higher doses (greater than 50 nanograms per mouse), this activity is lost. At these higher doses, however, substance P produced hyperalgesia when combined with naloxone and analgesia when combined with baclofen [β-(4-chlorophenyl)-gamma-aminobutyric acid]. Substance P may have dual actions in brain, releasing endorphins at very low doses and directly exciting neuronal activity in nociceptive pathways at higher doses.
Longitudinal Studies of Effects of Divorce on Children in Great Britain and the United States
Authors: Cherlin Andrew J. , Furstenberg Frank F. , Chase-Lansdale P. Lindsay , Kiernan Kathleen E. , Robins Philip K. , Morrison Donna Ruane , Teitler Julien O.
Published: October 2006

National, longitudinal surveys from Great Britain and the United States were used to investigate the effects of divorce on children. In both studies, a subsample of children who were in two-parent families during the initial interview (at age 7 in the British data and at ages 7 to 11 in the U.S. data) were followed through the next interview (at age 11 and ages 11 to 16, respectively). At both time points in the British data, parents and teachers independently rated the children's behavior problems, and the children were given reading and mathematics achievement tests. At both time points in the U.S. data, parents rated the children's behavior problems. Children whose parents divorced or separated between the two time points were compared to children whose families remained intact. For boys, the apparent effect of separation or divorce on behavior problems and achievement at the later time point was sharply reduced by considering behavior problems, achievement levels, and family difficulties that were present at the earlier time point, before any of the families had broken up. For girls, the reduction in the apparent effect of divorce occurred to a lesser but still noticeable extent once preexisting conditions were considered.
Clouds of Venus: A Preliminary Assessment of Microstructure
Authors: Knollenberg Robert G. , Hunten D. M.
Published: October 2006

The multimodal microstructure of the Venus cloud system has been examined. In addition to confirmed H
2
SO
4
droplets and suspected elemental sulfur, a highly concentrated aerosol population has been observed extending above, within, and below the cloud system. These aerosols appear to cycle through the cloud droplets, but can never be removed by the weak precipitation mechanisms present. All cloud particles are likely laced with aerosol contaminants. Sedimentation and decomposition of H
2
SO
4
in the droplets of the lower cloud region contribute more than 7 watts per square meter of heat flux equaling one-fourth of the solar net flux at 50 kilometers.
Initial Observations of the Nightside Ionosphere of Venus from Pioneer Venus Orbiter Radio Occultations
Authors: Kliore A. J. , Patel I. R. , Nagy A. F. , Cravens T. E. , Gombosi T. I.
Published: October 2006

Pioneer Venus orbiter dual-frequency radio occultation measurements have produced many electron density profiles of the nightside ionosphere of Venus. Thirty-six of these profiles, measured at solar zenith angles (χ) from 90.60° to 163.5°, are discussed here. In the "deep" nightside ionosphere (χ > 110°), the structure and magnitude of the ionization peak are highly variable; the mean peak electron density is 16,700 ± 7,200 (standard deviation) per cubic centimeter. In contrast, the altitude of the peak remains fairly constant with a mean of 142.2 ± 4.1 kilometers, virtually identical to the altitude of the main peak of the dayside terminator ionosphere. The variations in the peak ionization are not directly related to contemporal variations in the solar wind speed. It is shown that electron density distributions similar to those observed in both magnitude and structure can be produced by the precipitation on the nightside of Venus of electron fluxes of about 108 per square centimeter per second with energies less than 100 electron volts. This mechanism could very likely be responsible for the maintenance of the persistent nightside ionosphere of Venus, although transport processes may also be important.
Olfaction: Responses of a Decapod Crustacean Are Enhanced by Flicking
Authors: Schmitt Brian C. , Ache Barry W.
Published: October 2006

Periodic movements of the olfactory organs, known as "flicking," temporally enhance the response of the olfactory receptors of the spiny lobster to changes in stimulus concentration. This reflex provides the lobster with a physiological mechanism to compensate for the indiscrete temporal nature of chemical stimuli.
Water in Coal Pores: Low-Temperature Heat Capacity Behavior of the Moisture in Wyodak Coal
Authors: Mraw S. C. , Naas-O'Rourke D. F.
Published: October 2006

The low-temperature heat capacity behavior of naturally occurring water in Wyodak coal indicates that there are two types of water present. More than two-thirds is "nonfreezable," displaying no evidence of a phase transition in the neighborhood of 273 K where normal bulk water melts. The remainder is "freezable," displaying a somewhat distorted heat capacity peak, which is indicative of a phase transition. This evidence suggests that the nonfreezable water is either adsorbed on the internal surfaces of the coal or is in smaller pores, whereas the freezable water is in larger pores. Parallels to the heat capacity behavior of the coal-water system include the water in a porous ceramic, water in the mineral endellite, and water in the protein collagen.
Burial Rates, Growth Rates, and Size Distributions of Deep-Sea Manganese Nodules
Authors: Heath G. Ross
Published: October 2006

The size distributions of deep-sea manganese nodules are consistent with a simple model of uniform growth at a few millimeters per million years and with the same probability of burial for all nodules, regardless of size. The model suggests that most nodules spend 1 million years or less on the sea floor.
Observation of a Subsurface Oil-Rich Layer in the Open Ocean
Authors: Harvey George R. , Requejo Adolfo G. , McGillivary Philip A. , Tokar John M.
Published: October 2006

A layer of water at a depth of 200 meters containing 3 to 12 milligrams per liter of oil was found during February and March 1978 over a distance of 800 nautical miles in the southwest North Atlantic and the eastern Caribbean. The geochemistry and carbon-14 activity of the oil shows it to be a weathered crude, probably from a submarine seep. Although the dimensions of the oily layer were not determined, conservative estimates indicate that more than I megaton could have been present.
Superacids
Authors: Olah George A. , Prakash G. K. Surya , Sommer Jean
Published: October 2006

Superacids, although first referred to as early as 1927, were only extensively studied in the last decade. Acidities up to 10
12
times that of sulfuric acid have now been obtained. The extremely low nucleophilicity of the counterions in superacidic systems is especially useful for the preparation of stable, electron-deficient cations, particularly carbocations. Many of these cations, which were formerly detectable only in the gas phase, can now be studied in solution. Novel organic syntheses that are not possible in ordinary acidic media can also be achieved in superacids, including syntheses of economically important hydrocarbons. The unique ability of superacids to bring about hydrocarbon transformations, even to activate methane to undergo electrophilic oligocondensation, can open up new fields in chemistry.
Seasonal Oxygen Isotopic Variations in Living Planktonic Foraminifera off Bermuda
Authors: Williams Douglas F. , Bé Allan W. H. , Fairbanks Richard G.
Published: October 2006

Seasonal variations in the oxygen-18/oxygen-16 ratio of calcite shells of living planktonic foraminifera in the Sargasso Sea off Bermuda are a direct function of surface water temperature. Seasonal occurrence as well as depth habitat are determining factors in the oxygen isotopic composition of planktonic foraminifera. These relationships may be used to determine the seasonal temperature contrast of oceans in the past.
Silicon in Carbonaceous Chondrite Metal: Relic of High-Temperature Condensation
Authors: Grossman Lawrence , Olsen Edward , Lattimer James M.
Published: October 2006

Electron microprobe analyses of an extraordinarily large metal grain from the Murchison type 2 carbonaceous chondrite gave 0.24 mole percent silicon. Thermodynamic calculations show that this is a natural consequence of condensation of alloys from the solar nebular gas at a total pressure 10
–5
≲
P
tot
< 10
–3
atmosphere, provided they failed to equilibrate with it after cooling to < 1200 kelvins.
Salinity Gradient Power: Utilizing Vapor Pressure Differences
Authors: Olsson Mark , Wick Gerald L. , Isaacs John D.
Published: October 2006

By utilizing the vapor pressure difference between high-salinity and low-salinity water, one can obtain power from the gradients of salinity. This scheme eliminates the major problems associated with conversion methods in which membranes are used. The method we tested gave higher conversion efficiencies than membrane methods. Furthermore, hardware and techniques being developed for ocean thermal energy conversion may be applied to this approach to salinity gradient energy conversion.
Zonal Temperature-Anomaly Maps of Indian Ocean Surface Waters: Modern and Ice-Age Patterns
Authors: Prell Warren L. , Hutson William H.
Published: October 2006

Maps of sea surface temperature anomalies in the Indian Ocean in modern and ice-age times reveal striking changes in its surface circulation. During the last glacial maximum (18,000 years before the present), the Indian Ocean had colder average zonal surface temperatures, a cooler and less extensive Agulhas Current, a distinct eastern boundary current, and decreased upwelling and a weaker southwest monsoon in its northwestern region.
Bird Predation on Forest Insects: An Exclosure Experiment
Authors: Holmes Richard T. , Schultz John C. , Nothnagle Philip
Published: October 2006

Exclusion experiments show that birds significantly reduce densities of larval Lepidoptera on forest understory vegetation. When insect densities are already low, bird predation may act both as a population regulator and as a strong agent of natural selection.
Morphologies and Origin of Elemental Carbon in the Environment
Authors: Griffin John J. , Goldberg Edward D.
Published: October 2006

Carbon particles extracted from sediments collected by box coring from southeastern Lake Michigan were compared with carbon particles extracted from oil, coal, and wood fly ash. Sediments deposited after 1900 contained coal, oil, and wood carbons; older sediments contained only wood carbon.
Bees Have Rules
Authors: Brines Michael L. , Gould James L.
Published: October 2006

Honey bees frequently dance with some view of the sky, orienting themselves to the sun or natural patterns of polarized skylight. Three new conventions have been discovered in the dance language which are used in these circumstances to eliminate potential ambiguity in the dance message.
Pierce's Disease Bacterium: Mechanism of Transmission by Leafhopper Vectors
Authors: Purcell Alexander H. , Finlay Allan H. , McLean Donald L.
Published: October 2006

The bacterium that causes Pierce's disease of grapevines is isolated most consistently from the foregut of its leafhopper vector
Graphocephala atropunctata
. As seen in light and scanning electron microscopy of infective leafhoppers, the bacteria are attached to the cibarial pump and the lining of the esophagus in the foregut where they appear to multiply. These findings suggest that the bacterium is transmitted from the foregut by egestion during feeding by infective leafhoppers.
Prevention of Monocarpic Senescence in Soybeans with Auxin and Cytokinin: An Antidote for Self-Destruction
Authors: Noodén L. D. , Kahanak G. M. , Okatan Y.
Published: October 2006

Foliar applications of α-naphthaleneacetic acid, together with 6-benzyladenine, prevent the seed-induced degeneration (monocarpic senescence) in soybeans. In addition to halting leaf yellowing and shedding, this treatment prevents the loss of starch and nitrogen that occurs during senescence of these leaves. Although nitrogen and starch are normally redistributed to support pod growth, pod development is not impaired by this treatment, apparently because photosynthesis and nitrogen assimilation continue.
Fluorine Is a Major Constituent of the Marine Sponge
Halichondria moorei
Authors: Gregson R. P. , Baldo B. A. , Thomas P. G. , Quinn R. J. , Bergquist P. R. , Stephens J. F. , Horne A. R.
Published: October 2006

Fluorine constitutes about 10 percent of the dry weight of the marine sponge
Halichondria moorei
. The fluorine occurs as potassium fluorosilicate, which is a potent anti-inflammatory agent. A closely related sponge living in the same habitat does not contain any fluorine. The habitat was found to be free of fluorine except for the small amount naturally present in seawater.
Aboriginal Indian Residence Patterns Preserved in Censuses and Allotments
Authors: Moore John H.
Published: October 2006

Early reservation annuity censuses and allotment ledgers, analyzed in concert, allow identification of sociologically significant subdivisions of Native American tribes. Using this method, Southern Cheyenne
manhao
or "bands" can be located on the allotment map of 1892 as discrete clusters of individuals known by name, age, and sex. Measurement of linear distances among individual allotments of family members enables us to quantify jural rules of postmarital residence and confirms in a test case that the descendents of the bands at the Sand Creek Massacre in fact resided matrilocally.
Graphoglyptid Burrows in Modern Deep-Sea Sediment
Authors: Ekdale A. A.
Published: October 2006

The complex, highly patterned, invertebrate burrow systems known as "graphoglyptids" in ancient sedimentary rocks have now been recovered in box cores of modern deep-sea sediment.
Spiroraphe
,
Cosmoraphe
, and
Paleodictyon
occur as grooves in the tops of washed cores, and they apparently were produced and maintained as horizontal tunnel systems just a few millimeters below the sediment surface. These burrows, which are important as indicators of deepwater sedimentary environments in ancient strata, have been predicted in the modern deep sea but have not been found there until now.
Melanesian Prehistory: Some Recent Advances
Authors: White J. Peter , Allen Jim
Published: October 2006

Human occupation of New Guinea had begun 50,000 years ago, but islands further east were settled only in Recent times. In part of the New Guinea highlands, wet and dry horticultural systems began by 9000 years ago. Local intensification is evident until the present, but only the most recent major crop (sweet potato, which has been grown in the region for less than 300 years) is documented. On the south coast, exchange systems and economies locally diversify over the last two millennia. In the Melanesian islands, exotic materials were moved 3000 kilometers 3000 years ago, but whether traders or colonists were involved is not yet clear. The prehistory of the area is proving more complex than was believed even a decade ago.
Electron Spin Resonance Dating of Animal and Human Bones
Authors: Ikeya Motoji , Miki Toshikatsu
Published: October 2006

Ages of fossil bones were determined by electron spin resonance spectroscopy. The electron spin resonance signal is associated with lattice defects or trapped centers produced by natural radiation in the bones and gives a measure of the total dose of natural radiation, or the archeological dose. Archeological doses were determined for samples of known age from a variety of sites and used to estimate apparent average annual rates of natural radiation at the sites. The method has the advantage that the sample need not be ground or heated, and it should be useful for dating biological materials.
Volcanic Activity and Climatic Changes
Authors: Bryson Reid A. , Goodman Brian M.
Published: October 2006

Radiocarbon dates of volcanic activity suggest variations that appear to be related to climatic changes. Historical eruption records also show variations on the scale of years to centuries. These records can be combined with simple climatic models to estimate the impact of various volcanic activity levels. From this analysis it appears that climatic prediction in the range of 2 years to many decades requires broad-scale volcanic activity prediction. Statistical analysis of the volcanic record suggests that some predictability is possible.
Laminated Diatomaceous Sediments from the Guaymas Basin Slope (Central Gulf of California): 250,000-Year Climate Record
Authors: Schrader Hans , Kelts Kerry , Curray Joseph , Moore David , Aguayo Eduardo , Aubry Marie-Pierre , Einsele Gerhardt , Fornari Daniel , Gieskes Joris , Guerrero Jose , Kastner Miriam , Lyle Mitchell , Matoba Yasumochi , Molina-Cruz Adolfo , Niemitz Jeffrey , Rueda Jaime , Saunders Andrew , Simoneit Bernd , Vaquier Victor
Published: October 2006

During Deep Sea Drilling Project-International Program of Ocean Drilling leg 64, December 1978 to January 1979, the initial test of the Deep Sea Drilling Project's hydraulic piston corer obtained an almost undisturbed section from a 152-meter hole into the sediments of the oxygen minimum zone at a depth of 655 meters along the Guaymas slope in the central Gulf of California. The section records variations in climate, productivity, and circulation for more than 250,000 years of Late Pleistocene to Holocene history with recordings of seasonal variations in these parameters in the laminated sections.
Potato Protoplasts in Crop Improvement
Authors: Shepard James F. , Bidney Dennis , Shahin Elias
Published: October 2006

Clonal populations regenerated from single-leaf cell protoplasts of the potato cultivar `Russet Burbank' display a high frequency of variation for several horticultural and disease resistance characters. Observations over a period of three tuber generations suggest stable changes in tuber shape, yield, and maturity date, in photo-period requirements for flowering, and in plant morphology. Enhanced resistance to early blight (
Alternaria solani
) and late blight (
Phytophthora infestans
) diseases also regularly occurs within regenerated populations. These findings are discussed in the context of possible application to varietal improvement, particularly as they pertain to asexually propagated plants.
Lunar Magnetic Anomalies and Surface Optical Properties
Authors: Hood L. L. , Schubert G.
Published: October 2006

For typical solar wind conditions, lunar magnetic anomalies with dipole moments
m
⪢ 5 × 10
13
gauss-cubic centimeters will strongly deflect the solar wind, producing local plasma voids at the lunar surface. The correlation of the largest observed anomalies (
m
∼ 10
16
gauss-cubic centimeters) with unusual, relatively high albedo surface features may therefore imply that solar wind ion bombardment is an important determinant of the optical properties of the lunar surface.
Oil Shales and Carbon Dioxide
Authors: Sundquist Eric T. , Miller G. A.
Published: October 2006

During retorting of oil shales in the western United States, carbonate minerals are calcined, releasing significant amounts of carbon dioxide. Residual organic matter in the shales may also be burned, adding more carbon dioxide to the atmosphere. The amount of carbon dioxide produced depends on the retort process and the grade and mineralogy of the shale. Preliminary calculations suggest that retorting of oil shales from the Green River Formation and burning of the product oil could release one and one-half to five times more carbon dioxide than burning of conventional oil to obtain the same amount of usable energy. The largest carbon dioxide releases are associated with retorting processes that operate at temperatures greater than about 600 °C.
Soot in Urban Atmospheres: Determination by an Optical Absorption Technique
Authors: Rosen H. , Hansen A. D. A. , Dod R. L. , Novakov T.
Published: October 2006

We have used the high optical absorptivity of urban and source particulates to trace their "graphitic" component. The optical absorptivity and the particulate carbon loading show a strong correlation. Analyses of the data indicate that primary soot emissions compose a major fraction of the carbonaceous aerosol and put a low limit on secondary organic material produced in correlation with the ozone concentration.
Nitrous Oxide from Soil Denitrification: Factors Controlling Its Biological Production
Authors: Firestone Mary K. , Firestone Richard B. , Tiedje James M.
Published: October 2006

Increasing concentrations of nitrate, nitrite, and molecular oxygen enhanced production of nitrous oxide relative to molecular nitrogen during denitrification in soils. Soil acidity interacted with nitrate to increase the ratio of nitrous oxide to molecular nitrogen. In response to anoxic conditions, nitrous oxide production initially increased but nitrous oxide was then consumed, a pattern which resulted from the sequential synthesis of nitrogenous oxide reductases.
Conductive Polymers
Authors: Mort J.
Published: October 2006

Recent research has shown that polymers, normally thought of as being insulators, exhibit a wide range of electrical conductive properties.
High-Field, High-Current Superconductors
Authors: Hulm J. K. , Matthias B. T.
Published: October 2006

This article deals with superconducting materials which have zero electrical resistance while carrying high electrical current densities (around 10
6
amperes per square centimeter) in high magnetic fields (up to 50 teslas). The technological importance of these materials is due to their use in the windings of loss-free electromagnets which generate high magnetic fields. Such magnets are the foundation for superconducting electrotechnology, a rapidly growing field whose applications include advanced electrical machines and fusion reactors. The article focuses primarily on the materials aspects of this new technology. A brief overview is given of the physical principles which underlie this special type of superconducting behavior, and some of the important basic parameters are examined. The technology required to adapt the materials to electromagnets is also discussed. A few concluding remarks concern future possibilities for materials that can be used in generating very high magnetic fields.
Virus-Induced Diabetes Mellitus: Reovirus Infection of Pancreatic β Cells in Mice
Authors: Onodera Takashi , Jenson A. Bennett , Yoon Ji-Won , Notkins Abner Louis
Published: October 2006

Reovirus type 3, passaged in pancreatic β-cell cultures, produced an insulitis when inoculated into 1- to 2-week-old mice. By means of a double-label antibody technique, in which we used fluorescein-labeled antibody to reovirus and rhodamine-labeled antibody to insulin, reovirus antigens were found in β cells. By electron microscopy, viral particles in different stages of morphogenesis were observed in insulin-containing β cells but not glucagon-containing α cells. The infection resulted in destruction of β cells, reduction in the insulin content of the pancreas, and alteration in the host's capacity to respond normally to a glucose tolerance test.
Influence of a Phase Transition of Ice on the Heat and Mass Balance of Comets
Authors: Klinger J.
Published: October 2006

Differences in gas production rates of comets may be explained in part by the phase transition of ice in the comet nuclei.
Multiple Mating-Type Specificities in the Flax Rust
Melampsora lini
Authors: Lawrence Gregory J.
Published: October 2006

The results of selfing and intercrossing two strains of the flax rust fungus
Melampsora lini
indicate that this species does not possess a simple (+) and (–) mating system. Instead, the data are consistent with the assumption that the genetic control of mating type in
Melampsora lini
is similar to that in the mushroom
Schizophyllum commune
, in which mating type is determined by two factors, each of which is controlled by two linked loci.
Southwest Monsoon of 1979: Chemical and Biological Response of Somali Coastal Waters
Authors: Smith S. L. , Codispoti L. A.
Published: October 2006

In 1979 two areas of upwelling were observed off Somalia, one near 10°N and one near 5°N. The areas of upwelling were characterized by sea surface temperatures between 17° and 22°C, high concentrations of surface nutrients (5 to 20 micromoles of nitrate per liter) and surface chlorophyll a (0.4 to 5.0 milligrams per cubic meter), primary productivity averaging 1.7 grams of carbon per square meter per day, and a phytoplankton assemblage dominated numerically by the diatom
Nitzschia delicatissima
.
Carbynes: Carriers of Primordial Noble Gases in Meteorites
Authors: Whittaker A. Greenville , Watts Ethel J. , Lewis Roy S. , Anders Edward
Published: October 2006

Five carbynes (triply bonded allotropes of carbon) have been found by electron diffraction in the Allende and Murchison carbonaceous chondrites: carbon VI, VIII, X, XI, and (tentatively) XII. From the isotopic composition of the associated noble-gas components, it appears that the carbynes in Allende (C3V chondrite) are local condensates from the solar nebula, whereas at least two carbynes in Murchison (C2 chondrite) are of exotic, presolar origin. They may be dust grains that condensed in stellar envelopes and trapped isotopically anomalous matter from stellar nucleosynthesis.
Phytoplankton Pigments from the Nimbus-7 Coastal Zone Color Scanner: Comparisons with Surface Measurements
Authors: Gordon Howard R. , Clark Dennis K. , Mueller James L. , Hovis Warren A.
Published: October 2006

The removal of atmospheric effects from Nimbus-7 Coastal Zone Color Scanner (CZCS) images reveals eddy-like ocean turbidity patterns not apparent in the original calibrated images. Comparisons of the phytoplankton pigment concentrations derived from the corrected CZCS radiances with surface measurements agree to within less than 0.5 log
C
, where
C
is the sum of the concentrations of chlorophyll a plus phaeopigments
a
(in milligrams per cubic meter).
Canopy Orientation: A New Kind of Orientation in Ants
Authors: Hölldobler Bert
Published: October 2006

Celestial cues, such as the sun or patterns of polarized sky light, appear to have no detectable effect in the precise homing orientation of foragers of
Paltothyreus tarsatus
Field and laboratory experiments reveal that canopy patterns are a major influence in the home range orientation of this ponerine ant, a common species in African forests. Canopy orientation appears to be well suited to the restrictive lighting conditions of tropical forests.
JH Zero: New Naturally Occurring Insect Juvenile Hormone from Developing Embryos of the Tobacco Hornworm
Authors: Bergot B. John , Jamieson Gene C. , Ratcliff Milton A. , Schooley David A.
Published: October 2006

A new insect juvenile hormone was isolated from developing embryos of the tobacco hornworm moth,Manduca sexta. The new hormone was found with juvenile hormone I and is a 1-carbon homolog of this substance. The assigned structure is methyl (2E,6E,10-cis)-10,11-epoxy-3,7-diethyl-11-methyl-2,6-tridecadienoate, which constitutes a trishomosesquiterpenoid skeleton. This is the first chemical identification of any juvenile hormone from insect eggs.
Chemical Mimicry as an Integrating Mechanism: Cuticular Hydrocarbons of a Termitophile and Its Host
Authors: Howard Ralph W. , McDaniel C. A. , Blomquist Gary J.
Published: October 2006

The staphylinid beetle
Trichopsenius frosti
Seevers has the same cuticular hydrocarbons as those of its host termite
Reticulitermes flavipes
(Kollar) and it biosynthesizes them. These cuticular hydrocarbons probably serve as the primary mechanism by which
Trichopsenius frosti
integrates itself into the termite colony.