bluuebunny/crossref_metadata_2025 huggingface dataset:
The Upgraded Arecibo Observatory
Authors: LaLonde L. M.
Published: October 2006

Arecibo Observatory's giant spherical reflector antenna has undergone a massive upgrading over the past 3 years. The surface of the reflector has been replaced with aluminum panels to obtain an accuracy of 3.2 mm r.m.s. over the reflector surface. The superstructure has been stabilized and modified to permit operation at S-band frequencies. A high-power S-band radar transmitter has been added to the existing UHF system. These additions and improvements provide the observatory with new and promising research capabilities in the fields of radio and radar astronomy.
Asteroids: Surface Composition from Reflection Spectroscopy
Authors: McCord Thomas B. , Gaffey Michael J.
Published: October 2006

Minerals partly composing the surfaces of 14 asteroids are determined by using asteroid reflectance spectra and optical properties of meteorites and other materials. Individual electronic absorption features are identified in the asteroids' spectra. The energies, relative strengths, and shapes of these features are interpreted by using laboratory and theoretical studies. Analysis of the initial 14 asteroid reflectance spectra indicates the presence of the following types of surface materials: six carbonaceous chondrite-like; two stony-iron-like (metal/silicate ∼ 1); one iron meteorite-like; one basaltic achondrite-like; and four silicate-metal assemblages (metal/silicate ∼ 0.25). These results support the conclusion that the asteroid belt is a source of at least some meteoritic material, and they show a relation between certain asteroids and certain classes of meteorites.
Directed Chromosome Loss by Laser Microirradiation
Authors: Berns Michael W.
Published: October 2006

In this article I have presented data that indicate the feasibility of attaining the five objectives outlined in the introduction. It should be possible to assign genes to specific chromosome regions by (i) selective DNA deletion of a 0.25- to 0.5-μm segment of one or both homologous chromosomes, (ii) deletion of one or both entire homologous chromosomes, or (iii) combining cell fusion with selective deletion of whole chromosomes and then deletion of chromosome segments.

By laser microirradiation it should be possible to determine which chromosomes and chromosome regions are essential for immediate cell survival by removing from individual cells whole chromosomes, and chromosome segments from each of the chromosomes in the karyotype, and then assessing the cloning efficiency of each cell. For example, we have already determined that removal of one large chromosome No. 1 from PTK
2
cells does not prevent the cell from undergoing a subsequent mitosis.

It should also be possible to generate new classes of mutants by damaging small selected areas of DNA with the laser beam and then cloning the irradiated cells—but this has yet to be demonstrated. This procedure might reveal recessive alleles on the nonirradiated homolog, or might result in the direct production of a genetic mutation. Irradiation of identical places on both homologous chromosomes could result in deletion of a genetic locus which ultimately might be detected as a deficiency in a metabolic pathway or some other cellular abnormality.

Studies on chromosome stability and DNA constancy can be conducted with laser irradiated cells. For example, the karyotypic analysis of chromosome No. 1 suggests that a cellular mechanism exists to maintain the constancy of this chromosome in both the diploid and tetraploid cell lines. The same approach could be used with each of the chromosomes in the karyotype. Various cytochemical procedures could be used for making quantitative DNA studies of the cells, and chromosome and DNA analyses could be performed at varying times following laser microirradiation.

It might also be possible to study the repair of chromosomal damage caused by laser irradiation. The cells could be examined by autoradiographic, cytochemical, and electron microscopy procedures at varying times after irradiation, and because the precise location, time, and nature of the mutational event would be known, subsequent analysis of repair and alteration would be facilitated.
Decline of DDT Residues in Migratory Songbirds
Authors: Johnston David W.
Published: October 2006

Analyses of ten species of migratory songbirds killed when the birds flew into television towers in Florida showed a progressive decline in the concentration of DDT and its metabolites (DDD and DDE) in their fat depots for the period 1964 to 1973. This decline is apparently correlated with the decreased usage of DDT in the United States during the same time.
Antihistamines Block Radiation-Induced Taste Aversions
Authors: Levy Carolyn J. , Carroll Marilyn E. , Smith James C. , Hofer Kurt G.
Published: October 2006

When rats are treated with an antihistamine prior to being given sublethal doses of ionizing radiation, the formation of a conditioned saccharin aversion is completely inhibited. A profound aversion could be conditioned with histamine diphosphate as the aversive stimulus. The increase in histamine production after radiation exposure represents the physiological basis of radiation-induced taste aversions.
Callisto: Disk Temperature at 3.71-Centimeter Wavelength
Authors: Berge Glenn L. , Muhleman Duane O.
Published: October 2006

We observed the radio emission of Callisto with a three-element interferometer at the time of the 1973 opposition of Jupiter. Special care was taken to remove the residual, unresolved contribution from Jupiter itself in the antenna side lobes. The resulting disk temperature at a wavelength of 3.71 centimeters, assuming a radius of 2500 ± 75 kilometers for Callisto, was 101° ± 25°K. This temperature is much more consistent with emission from a simple dielectric sphere than the considerably higher temperatures that have been reported for wavelengths of 3.5 and 8.2 millimeters.
Marine Phosphorite Deposits and the Nitrogen Cycle
Authors: Piper D. Z. , Codispoti L. A.
Published: October 2006

We have attempted to demonstrate a possible relationship between phosphorite deposition and an increase in marine denitrification. The studies of others indicate that major phosphorite deposits are often associated with black shales and accumulated during only a few epochs of geologic history. Some of these epochs were also marked by mass extinctions of organisms. Such events are not as precisely nor as strongly correlated as we would like. Nevertheless, the correlations are strong enough to encourage further consideration of the effects of possible changes in the rate of denitrification within ancient oceans on the origin of phosphorite deposits, the extinctions of marine organisms, variations in the overall level of biological activity, and temporal fluctuations in the organic carbon content of sedimentary rocks.
Pioneer 11 Encounter: Preliminary Results from the Ames Research Center Plasma Analyzer Experiment
Authors: Mihaloy J. D. , Collard H. R. , McKibbin D. D. , Wolfe J. H. , Intriligator D. S.
Published: October 2006

Pioneer 11 observations of the interaction of Jupiter's magnetosphere with the distant solar wind have confirmed the earlier Pioneer 10 observations of the great size and extreme variability of the outer magnetosphere. The nature of the plasma transitions across Jupiter's bow shock and magnetopause as observed on Pioneer 10 have also been confirmed on Pioneer 11. However, the northward direction of the Pioneer 11 outbound trajectory and the distance of the final magnetopause crossing (80 Jupiter radii) now suggest that Jupiter's magnetosphere is extremely broad with a half-thickness (normal to the ecliptic plane in the noon meridian) which is comparable to or greater than the sunward distance to the nose.
Specific DNA Binding by c-Myb: Evidence for a Double Helix-Turn-Helix-Related Motif
Authors: Gabrielsen Odd S. , Sentenac André , Fromageot Pierre
Published: October 2006

The c-Myb protein is a sequence-specific DNA binding protein that activates transcription in hematopoietic cells. Three imperfect repeats (R
1
, R
2
, and R
3
) that contain regularly spaced tryptophan residues form the DNA binding domain of c-Myb. A fragment of c-Myb that contained the R
2
and R
3
regions bound specifically to a DNA sequence recognized by c-Myb plus ten additional base pairs at the 3′ end of the element. The R
2
R
3
fragment was predicted to contain two consecutive helix-turn-helix (HTH) motifs with unconventional turns. Mutagenesis of amino acids in R
2
R
3
at positions that correspond to DNA-contacting amino acids in other HTH-containing proteins abolished specific DNA binding without affecting nonspecific DNA interactions.
Earth as an Intense Planetary Radio Source: Similarities to Jupiter and Saturn
Authors: Kaiser M. L. , Stone R. G.
Published: October 2006

Observations from spacecraft have revealed naturally occurring radio emission emanating from two regions near Earth. The characteristics of these two sources suggest a correlation with areas of known electron precipitation. The possibility of a similar production mechanism for observed nonthermal radio emissions from other planetary magnetospheres permits the polar magnetic field strengths of Jupiter and Saturn to be predicted.
Nectar Fluorescence under Ultraviolet Irradiation
Authors: Thorp Robbin W. , Briggs Dennis L. , Estes James R. , Erickson Eric H.
Published: October 2006

Nectar, which fluoresces in the visible and absorbs in the ultraviolet spectrum when irradiated by ultraviolet light, occurs in many bee-pollinated plants. It is suggested that these characteristics function as direct visual cues by which bees can evaluate the quantities of nectar available. Thus, they assume an important role in pollination of the flowers and foraging efficiency of bees.
The 1973 Flood and Man's Constriction of the Mississippi River
Authors: Belt C. B.
Published: October 2006

The progressive constriction of the Mississippi for navigation since 1837 has caused bottom erosion in some stretches. In others the bottom oscillates up and down with time. The high stages rise much more rapidly. Constriction of the river channel causes flooding and makes floods higher; thus navigation works degrade the protection afforded by levees. The combination of navigation works and levees causes significant rises in the stages of floods. Additional channel constriction and levee building will cause further problems. The 1973 flood's record was man-made.
Identification of the Envelope V3 Loop as the Primary Determinant of Cell Tropism in HIV-1
Authors: Hwang Stephen S. , Boyle Terence J. , Lyerly H. Kim , Cullen Bryan R.
Published: October 2006

Cells of the monocyte-macrophage lineage are targets for human immunodeficiency virus-1 (HIV-1) infection in vivo. However, many laboratory strains of HIV-1 that efficiently infect transformed T cell lines replicate poorly in macrophages. A 20-amino acid sequence from the macrophage-tropic BaL isolate of HIV-1 was sufficient to confer macrophage tropism on HTLV-IIIB, a T cell line-tropic isolate. This small sequence element is in the V3 loop, the envelope domain that is the principal neutralizing determinant of HIV-1. Thus, the V3 loop not only serves as a target of the host immune response but is also pivotal in determining HIV-1 tissue tropism.
Anti-HIV and Anti-Anti-MHC Antibodies in Alloimmune and Autoimmune Mice
Authors: Kion Tracy A. , Hoffmann Geoffrey W.
Published: October 2006

Alloimmune mice (mice that have been exposed to cells from another murine strain) were shown to make antibodies against gp120 and p24 of human immunodeficiency virus (HIV), and mice of the autoimmune strains MRL-
lpr
/
lpr
and MRL-+/+ made antibodies against gp120. This is surprising because the mice were not exposed to HIV. Furthermore, anti-anti-MHC antibodies (molecules that have shapes similar to those of major histocompatibility complex molecules) were detected in both alloimmune sera and MRL mice. These results are discussed in the context of a possible role for allogeneic stimuli in the pathogenesis of acquired immunodeficiency syndrome, as suggested by an idiotypic network model.
Solar Heating and Cooling
Authors: Duffie John A. , Beckman William A.
Published: October 2006

We have adequate theory and engineering capability to design, install, and use equipment for solar space and water heating. Energy can be delivered at costs that are competitive now with such high-cost energy sources as much fuel-generated, electrical resistance heating. The technology of heating is being improved through collector developments, improved materials, and studies of new ways to carry out the heating processes.

Solar cooling is still in the experimental stage. Relatively few experiments have yielded information on solar operation of absorption coolers, on use of night sky radiation in locations with clear skies, on the combination of a solar-operated Rankine engine and a compression cooler, and on open cycle, humidification-dehumidification systems. Many more possibilities for exploration exist. Solar cooling may benefit from collector developments that permit energy delivery at higher temperatures and thus solar operation of additional kinds of cycles. Improved solar cooling capability can open up new applications of solar energy, particularly for larger buildings, and can result in markets for retrofitting existing buildings.

Solar energy for buildings can, in the next decade, make a significant contribution to the national energy economy and to the pocketbooks of many individual users. very large aggregate enterprises in manufacture, sale, and installation of solar energy equipment can result, which can involve a spectrum of large and small businesses. In our view, the technology is here or will soon be at hand; thus the basic decisions as to whether the United States uses this resource will be political in nature.
Electric Power from Differences in Salinity: The Dialytic Battery
Authors: Weinstein John N. , Leitz Frank B.
Published: October 2006

An array of alternating anion and cation exchange membranes can be used to generate electric power from the free energy of mixing of river and sea waters. A simple mathematical model, which predicts experimental results well, is useful in exploring conditions for optimization of the process. Major, but not impossible, improvements in technology would be required to bring the cost of power from the dialytic battery into line with foreseeable energy prices.
Light Control of Growth Form in Colonial Reef Corals: Computer Simulation
Authors: Graus Richard R. , Macintyre Ian G.
Published: October 2006

Computer simulation with plotter output reveals the close interrelation between ambient light and the skeletal morphogenesis of the massive Caribbean reef coral
Montastrea annularis
. This technique illustrates a new quantitative approach to evaluating ecological growth responses of colonial organisms.
Cloud Condensation Nuclei on the Atlantic Seaboard of the United States
Authors: Radke Lawrence F. , Hobbs Peter V.
Published: October 2006

Concentrations of cloud condensation nuclei measured along the East Coast from Virginia to Long Island ranged from 1000 to 3500 per cubic centimeter as compared to 100 per cubic centimeter in clean maritime air and 300 per cubic centimeter in continental air. The global anthropogenic production rate of cloud condensation nuclei may be comparable to the natural production rate; in some industrial areas cloud condensation nuclei are dominated by anthropogenic sources.
Polyphosphazenes: New Polymers with Inorganic Backbone Atoms
Authors: Allcock Harry R.
Published: October 2006

Polyphosphazenes are emerging as a new class of macromolecules that have an obvious future as technological elastomers, films, fibers, and textile treatment agents. However, they also possess almost unique attributes for use in biomedicine as reconstructive plastics or as drug-carrier molecules. Moreover, their possible value as "pseudo-protein" model polymers is an exciting prospect.
Dissolved Organic Matter and Heterotrophic Microneuston in the Surface Microlayers of the North Atlantic
Authors: Sieburth John McN. , Willis Paula-Jean , Johnson Kenneth M. , Burney Curtis M. , Lavoie Dennis M. , Hinga Kenneth R. , Caron David A. , French Frederick W. , Johnson Paul W. , Davis Paul G.
Published: October 2006

Dissolved organic carbon, carbohydrates, and adenosine triphosphate in the size fractions 0.2 to 3 micrometers and 3 to 1000 micrometers are significantly enriched in the upper 150-micrometer surface layer compared to subsurface water, mean enrichment factors being 1.6, 2.0, 2.5, and 3.1, respectively. When calculated as a 0.1-micrometer microlayer of wet surfactants, the mean concentration of organic matter was 2.9 grams per liter, of which carbohydrates accounted for 28 percent. The data for plant pigments and particulate adenosine triphosphate indicated that bacterioneuston was enriched at seven of nine stations while phagotrophic protists were enriched at five stations. Instances of enrichment and inhibition were verified by cultural data for bacteria and amoebas. The observations indicate that the surface microlayers are largely heterotrophic microcosms, which can be as rich as laboratory cultures, and that an appreciable part of the dissolved organic carbon is carbohydrate of phytoplankton origin, released and brought to the surface by migrating and excreting phagotrophic protists.
Antigenic Shift of Visna Virus in Persistently Infected Sheep
Authors: Narayan O. , Griffin D. E. , Chase J.
Published: October 2006

Visna viruses isolated from persistently infected sheep were antigenically distinct from the plaque-purified virus used for inoculation. The selection of antigenic variants under antibody pressure, thought to occur in vivo, was reproduced in sheep cell cultures inoculated with plaque-purified visna virus and maintained in antibody. Antigenic shift may be a mechanism for persistence of virus in slow or recurrent viral infections.
A Homolog of the
armadillo
Protein in
Drosophila
(Plakoglobin) Associated with E-Cadherin
Authors: McCrea Pierre D. , Turck Christoph W. , Gumbiner Barry
Published: October 2006

Three cytoplasmic proteins, called catenins, bind to the cytoplasmic tail of the epithelial cell-cell adhesion molecule E-cadherin. The complementary DNA sequence was determined for the 92-kilodalton β catenin of
Xenopus laevis
. The sequence is homologous to mammalian plakoglobin, a protein of desmosomal and
zonula adherens
cell junctions, and to the plakoglobin homolog in
Drosophila melanogaster
, the product of the segment polarity gene
armadillo
. A monoclonal antibody to bovine plakoglobin recognizes the analogous β catenin in the Madin-Darby canine kidney (MDCK) cell line.
Armadillo
plakoglobin may link E-cadherin to the underlying actin cytoskeleton at cell-cell junctions; the E-cadherin-catenin protein complex may also participate in the transmission of developmental information.
Systemic Delivery of Human Growth Hormone by Injection of Genetically Engineered Myoblasts
Authors: Dhawan Jyotsna , Pan Lydia C. , Pavlath Grace K. , Travis Marilyn A. , Lanctot Andrea M. , Blau Helen M.
Published: October 2006

A recombinant gene encoding human growth hormone (hGH) was stably introduced into cultured myoblasts with a retroviral vector. After injection of genetically engineered myoblasts into mouse muscle, hGH could be detected in serum for 3 months. The fate of injected myoblasts was assessed by coinfecting the cells with two retroviral vectors, one encoding hGH and the other encoding β-galactosidase from
Escherichia coli
. These results provide evidence that myoblasts, which can fuse into preexisting multinucleated myofibers that are vascularized and innervated, may be advantageous as vehicles for systemic delivery of recombinant proteins.
Shock-Produced Olivine Glass: First Observation
Authors: Jeanloz Raymond , Ahrens Thomas J. , Lally J. S. , Nord G. L. , Christie J. M. , Heuer A. H.
Published: October 2006

Transmission electron microscope (TEM) observations of an experimentally shock-deformed single crystal of natural peridot, (Mg
0.88
Fe
0.12
)
2
SiO
4
, recovered from peak pressures of about 56 × 10
9
pascals revealed the presence of amorphous zones located within crystalline regions with a high density of tangled dislocations. This is the first reported observation of olivine glass. The shocked sample exhibits a wide variation in the degree of shock deformation on a small scale, and the glass appears to be intimately associated with the highest density of dislocations. This study suggests that olivine glass may be formed as a result of shock at pressures above about 50 to 55 × 10
9
pascals and that further TEM observations of naturally shocked olivines may demonstrate the presence of glass.
Calcium Carbonate Production of the
Mare Incognitum
, the Upper Windward Reef Slope, at Enewetak Atoll
Authors: Smith S. V. , Harrison J. T.
Published: October 2006

Corals and algal pavement produce calcium carbonate more slowly on the windward reef slope of Enewetak Atoll than on the reef flat despite the high standing crop of reef-building organisms on the slope. The capacity of reefs to remain at or near sea level is therefore not determined primarily by growth on the seaward slope.
Resource Partitioning in Bumble Bees: The Role of Behavioral Factors
Authors: Morse Douglass H.
Published: October 2006

Small
Bombus ternarius
workers for age most frequently on the distal parts of goldenrod flower clusters when large
B. terricola
workers are present. This shift results from
B. ternarius
avoiding
B. terricola
. In this way
B. ternarius
can exploit, without conflict, resources whose availability changes constantly because of fluctuating numbers of larger consumers.
Disruption of Sex Pheromone Communication in a Nematode
Authors: Bone L. W. , Shorey H. H.
Published: October 2006

Males of
Nippostrongylus brasiliensis
, an intestinal parasite of rodents, were maintained in an environment permeated with pheromone produced by females of the species. After the males were removed from that environment, their subsequent ability to orient to a gradient of the pheromone emanating from living females was greatly reduced for periods up to 2 hours. This phenomenon might serve as the basis for a new, selective antihelminthic technique in which the premating communication between males and females is disrupted.
Agriculture and Behavioral Science: Emerging Orientations
Authors: Saint William S. , Coward E. Walter
Published: October 2006

New research orientations are emerging in behavioral science approaches to agricultural development. These new orientations are the product of both experience gained during the era that followed the Green Revolution and a response to changing goals in agricultural development that now place a greater emphasis on considerations of participation and equity. They also reflect a more general concern with the relation of technology and society growing out of efforts to understand energy and environmental problems. These orientations are characterized by a shift away from a conceptual perspective emphasizing communication to one in which technology and social organization are deemed essential in understanding and promoting agricultural development.

This changing conceptual perspective is being manifested in the research process from which technology develops. Use of ecological systems approaches to the study of farming systems is increasing. The importance of understanding traditional agriculture is becoming evident and technology development methodologies are beginning to simulate farm conditions at the research center and to conduct experimental research on the farm. The appreciation of technology as a variable is leading to the development of alternative technologies adapted to different socionatural situations. As these emerging orientations become elaborated, they enhance the contributions which behavioral scientists can make to agricultural development.
Radioactive Wastes: A Comparison of U.S. Military and Civilian Inventories
Authors: Krugmann Hartmut , von Hippel Frank
Published: October 2006

Contrary to widespread belief, the accumulated inventory of fission products generated by the still small U.S. civilian nuclear power industry may already be comparable to that generated in the past by U.S. military nuclear programs. Although the volumes of the military wastes are very large, they are on the average almost 100 times more dilute than projected commercial high-level wastes.
Empirical Explorations of SYNCHEM
Authors: Gelernter H. L. , Sanders A. F. , Larsen D. L. , Agarwal K. K. , Boivie R. H. , Spritzer G. A. , Searleman J. E.
Published: October 2006

During the past several years, a substantial body of experience has accumulated in the use of SYNCHEM, a large-scale program which is able to discover synthesis routes for relatively complex organic structures without on-line guidance on the part of its chemist user. These results indicate that the approach to computer-directed organic synthesis route discovery embodied in the program has been valid and reasonable, and that SYNCHEM is likely to be fruitful from the point of view of its intended users as well as for our research objectives in artificial intelligence. The experiments have revealed a number of insufficiencies in the program as well. Most of these are rectified in SYNCHEM2, a revised version of the program which includes, among other improvements, a more highly developed synthesis search algorithm and the routine consideration of stereochemistry.
Grand Banks and J-Anomaly Ridge: A Geological Comparison
Authors: Gradstein F. M. , Grant A. C. , Jansa L. F.
Published: October 2006

Geological and geophysical evidence supports the hypothesis that the J-anomaly ridge was a part of the Grand Banks in (late) Early Cretaceous time.
Correction of a Defect in Mammalian GPI Anchor Biosynthesis by a Transfected Yeast Gene
Authors: DeGasperi R. , Thomas L. J. , Sugiyama E. , Chang H. M. , Beck P. J. , Orlean P. , Albright C. , Waneck G. , Sambrook J. F. , Warren C. D. , Yeh E. T. H.
Published: October 2006

Glycosylphosphatidylinositol (GPI) serves as a membrane anchor for a large number of eukaryotic proteins. A genetic approach was used to investigate the biosynthesis of GPI anchor precursors in mammalian cells. T cell hybridoma mutants that cannot synthesize dolichol-phosphate-mannose (Dol-P-Man) also do not express on their surface GPI-anchored proteins such as Thy-1 and Ly-6A. These mutants cannot form mannose-containing GPI precursors. Transfection with the yeast Dol-P-Man synthase gene rescues the synthesis of both Dol-P-Man and mannose-containing GPI precursors, as well as the surface expression of Thy-1 and Ly-6A, suggesting that Dol-P-Man is the donor of at least one mannose residue in the GPI core.
Ocean Surface Currents Mapped by Radar
Authors: Barrick D. E. , Evans M. W. , Weber B. L.
Published: October 2006

A high-frequency radar remote-sensing system for measuring and mapping near-surface ocean currents in coastal waters has been analyzed and described. A transportable prototype version of the system was designed, constructed, and tested. With two units operating tens of kilometers apart, the currents were mapped in near real time at a grid of points 3 by 3 km covering areas exceeding 2000 km
2
, out to a distance of about 70 km from the shore. Preliminary estimates of the precision of current velocity measurements show it to be better than 30 cm/sec.
High-Level and Long-Lived Radioactive Waste Disposal
Authors: Angino Ernest E.
Published: October 2006

No uniform international approach for handling the problem of high-level radioactive waste disposal exists. All the while, the volume of these wastes continues to grow. The only viable solution to the disposal problem is a geologic one. Burial of these wastes in solid form for long periods of time in mined cavities in salt or Precambrian crystalline rock formations is technically possible. Several steps in the burial process have already been demonstrated in Germany. The problem becomes more serious as the number of countries committed to the use of nuclear energy grows. If one considers the problems of seismic stability and worldwide distribution of salt deposits, the overwhelming need for an international solution to the waste disposal problem seems obvious.
Submarine Seepage of Natural Gas in Norton Sound, Alaska
Authors: Cline Joel D. , Holmes Mark L.
Published: October 2006

Unusual concentrations of dissolved two- to four-carbon alkanes were observed in the waters in Norton Sound in a localized area approximately 40 kilometers south of Nome, Alaska, in 1976. The hydrocarbons were identified in the near-bottom waters downcurrent for more than 100 kilometers from a sea-floor point source. Preliminary dynamic modeling estimates of the initial gas phase composition predict methane/ethane and ethane/propane ratios of 24 and 1.7, respectively, assuming the hydrocarbons were introduced by bubbles. The low ethane/propane ratio is indicative of gas from a liquid petroleum source rather than from nonassociated or biogenic natural gas. Preliminary data on the structural geology of Norton Basin lend support to the interpretation based on the hydrocarbon plume. Unconformably truncated strata dip basinward from the seep locus; acoustic anomalies and numerous steeply dipping faults in the immediate vicinity of the seep are corroborating evidence that shallow gas- or petroleum-charged sediments and strata coincide with avenues for migration of mobile hydrocarbons to the sea floor. These factors, taken in concert with the sedimentological regime, the recent revision (increase) of basin depth estimates, and the highly localized hydrocarbon source, strongly suggest a thermogenic rather than a recent biogenic origin for these gaseous compounds.
Oxygen and Hydrogen Isotopic Ratios in Plant Cellulose
Authors: Epstein Samuel , Thompson Peter , Yapp Crayton J.
Published: October 2006

The variations of the D/H and
18
O/
16
O ratios of nonexchangeable hydrogen and oxygen in plant cellulose reveal systematic differences between aquatic and terrestrial plant groups. The slope of δD versus δ
18
O of cellulose from a variety of aquatic plants is close to 8 (the meteoric water value), while the slope for a number of terrestrial species is greater than or equal to about 24. Two models involving incorporation of CO
2
and H
2
O into cellulose precursors are proposed to account for these differences. Effects of evaporative transpiration on the isotopic composition of water in leaves are measured and discussed in the context of these models.
Chemical Evidence for Separating the Psilotaceae from the Filicales
Authors: Cooper-Driver Gillian
Published: October 2006

The distribution of flavonoid compounds in
Psilotum
,
Tmesipteris
, and primitive filicalean ferns shows that it is unlikely the two groups are closely related. The Psilotaceae synthesize only amentoflavone and related biflavonyls which are totally absent from ferns. The primitive ferns contain the full complement of flavonols and proanthocyanidins, as found in all other filicalean families.
Evidence for Biased Gene Conversion in Concerted Evolution of Ribosomal DNA
Authors: Hillis David M. , Moritz Craig , Porter Calvin A. , Baker Robert J.
Published: October 2006

Concerted evolution is the production and maintenance of homogeneity within repeated families of DNA. Two mechanisms—unequal crossing over and biased gene conversion—have been the principal explanations of concerted evolution. Concerted evolution of ribosomal DNA (rDNA) arrays is thought to be largely the result of unequal crossing over. However, concerted evolution of rDNA in parthenogenetic lizards of hybrid origin is strongly biased toward one of two parental sequences, which is consistent with biased gene conversion as the operative mechanism. The apparent gene conversions are independent of initial genome dosage and result in homogenization of rDNA arrays across all nucleolar organizer regions.
Antibody-Dependent Lymphocytotoxicity Induced by Immunoglobulin G from Hodgkin's Disease Splenic Lymphocytes
Authors: Longmire Robert L. , Ryan Sherry , McMillan Robert , Lightsey Al , Heath Victor
Published: October 2006

Immunoglobulin G, produced in cultures of splenic lymphocytes obtained from patients with Hodgkin's disease, bound to a population of homologous peripheral blood lymphocytes and initiated antibody-dependent cell cytotoxicity in cultures from five out of eight patients. Two patients whose cultures produced negative results had minimal disease; the other was in remission. The target cells appear to be T lymphocytes; the effector cells bear Fc receptors that are inhibited by antigen-antibody complexes. Antibody-dependent cell cytotoxicity events may produce the anergy and lymphopenia often seen in Hodgkin's disease.
Thyroid Gangliosides with High Affinity for Thyrotropin: Potential Role in Thyroid Regulation
Authors: Mullin Brian R. , Pacuszka Tadeusz , Lee George , Kohn Leonard D. , Brady Roscoe O. , Fishman Peter H.
Published: October 2006

Thyroid cell membranes contain a multiplicity of gangliosides, some of which inhibit thyrotropin binding to thyroid membranes. The most potent inhibitor is a ganglioside which is present in only trace amounts and appears to have a novel structure. Thyroid gangliosides may play a role in relaying the hormonal message to the thyroid cell.
Eavesdropping: The Radio Signature of the Earth
Authors: Sullivan W. T. , Brown S. , Wetherill C.
Published: October 2006

In addition to searches for purposeful signals, those attempting interstellar communication should also consider the possibility of eavesdropping on radio emissions inadvertently "leaking" from other technical civilizations. To understand better the information which might be derivable from radio leakage, the case of planet earth is considered. The most detectable and useful escaping signals arise in a few BMEWS-type radar systems and in normal television broadcasting. A model including over 2000 television transmitters is used to demonstrate the wealth of astronomical and cultural information available from a distant observer's careful monitoring of frequency and intensity variations in individual video carriers (program material is
not
taken to be detectable).
Extraterrestrial Intelligence: An Observational Approach
Authors: Murray Bruce , Gulkis Samuel , Edelson Robert E.
Published: October 2006

The microwave region of the electromagnetic spectrum, a plausible regime for signals from extraterrestrial intelligences, is largely unexplored. With new technology, particularly in data processing and low-noise reception, surveys can be conducted over broad regions of frequency and space with existing antennas at flux densities plausible for interstellar signals. An all-sky, broad-band survey lasting perhaps 5 years can be structured so that even negative results would establish significant boundaries on the regime in which such signals may be found. The technology and techniques developed and much of the data acquired would be applicable to radio astronomy and deep-space communications.
European Corn Borer: Pheromone Polymorphism or Sibling Species?
Authors: Cardé R. T. , Roelofs W. L. , Harrison R. G. , Vawter A. T. , Brussard P. F. , Mutuura A. , Munroe E.
Published: October 2006

Electrophoretic analyses of the (
Z
) and (
E
) pheromone-attracted males of
Ostrinia nubilalis
(Hübner), the European corn borer, in an area of coexistence indicate that these strains are not freely interbreeding. Although the populations are morphologically indistinguishable, studies of allozyme, pheromone, and hybridization suggest that the (
Z
) and (
E
) entities are genetically differentiated, perhaps to the status of semi- or sibling species.
Isostasy in Australia and the Evolution of the Compensation Mechanism
Authors: McNutt Marcia K. , Parker Robert L.
Published: October 2006

A linear transfer function analysis has been applied to gravity and topographic data from Australia to calculate the isostatic response function of Dorman and Lewis. The Australian response function is considerably different from that calculated for the United States. The differences can be explained on the basis of an apparent evolution of the isostatic compensation mechanism in which viscoelastic creep occurs in the lithosphere and relaxes the initial long-wavelength elastic stresses.
Spectral Analyses of High-Frequency
P
n
and
S
n
Phases Observed at Great Distances in the Western Pacific
Authors: Walker Daniel A. , McCreery Charles S. , Sutton George H. , Duennebier Frederick K.
Published: October 2006

Both
P
n
and
S
n
phases recorded at distances greater than 3000 kilometers in the western Pacific have substantial amounts of energy at high frequencies, in some instances as high as 12 hertz for
P
n
and 15 hertz for
S
n
, A comparison of
P
n
and
S
n
spectra reveals generally higher energy levels and higher proportions of high-frequency to low-frequency energy for
S
n
than for
P
n
. Estimates of the effective quality factor,
Q
, indicate that the efficiency of
S
n
propagation may be two or three times that of
P
n
. First arrivals of
P
n
and
S
n
have apparent velocities in agreement with values for the uppermost mantle, whereas maximum-energy arrivals have apparent velocities in agreement with values for the lower crust.
Cellulose Digestion in the Midgut of the Fungus-Growing Termite
Macrotermes natalensis
: The Role of Acquired Digestive Enzymes
Authors: Martin Michael M. , Martin Joan S.
Published: October 2006

The midguts of adult workers of the higher termite species
Macrotermes natalensis
contain the entire set of digestive enzymes required for the digestion of native cellulose. The C
x
-cellulases and the β-glucosidases are produced, at least in part, by the termite's own midgut epithelium and salivary glands. The C
1
-cellulases, on the other hand, are acquired by the termites when they feed on a fungus that grows in their nests. We propose that the involvement of acquired digestive enzymes could serve as the basis for a general strategy of resource utilization and further suggest that the acquisition of digestive enzymes may be a widespread phenomenon among mycophagous invertebrates.
New Low-Dimensional Molecular Metals: Single-Crystal Electrical Conductivity of Nickel Phthalocyanine Iodide
Authors: Schramm C. J. , Stojakovic D. R. , Hoffman B. M. , Marks T. J.
Published: October 2006

Single crystals of NiPcI
1.0
(Pc = phthalocyanine), which are composed of one-dimensional stacks of (NiPc)
+0.33
molecules and chains of I
3
-
molecules, exhibit metallic electrical conductivity in the stacking direction. At room temperature the mean free path of the carrier is 3.3 to 8.2 angstroms.
Separation of the Sperm Agglutinin and the Acrosome Reaction-Inducing Substance in Egg Jelly of Starfish
Authors: Uno Yohko , Hoshi Motonori
Published: October 2006

The egg jelly of the starfish
Asterias amurensis
was separated into the fractions J1, J2, and J3 on a Sephadex G-100 column. The J1 fraction induced the acrosome reaction and J2 induced sperm agglutination. Chemical analysis and chromatography revealed that sperm agglutinin is similar to asterosaponin A.
U.S. Energy Demand: Some Low Energy Futures
Authors:   Demand and Conservation Panel of the Committee on Nuclear and Alternative Energy Systems
Published: October 2006

The basic features of the U.S. energy supply and utilization system change so slowly that an understanding of the dynamics of major change requires projections that extend several decades. Over such a time most energy-consuming capital stock is replaced, life-styles change, and technology evolves. This study of plausible low energy futures leans heavily on detailed engineering analysis of demand by sector, combined with econometric techniques where appropriate. The results indicate that, given time for the system to respond to prices, regulations, and incentives, U.S. energy demand is very elastic. Consequently, a major slowdown in demand growth can be achieved simultaneously with significant economic growth by substituting technological sophistication for energy consumption.
Atmospheric Input of Carbon Dioxide from Burning Wood
Authors: Wong C. S.
Published: October 2006

The atmospheric input of carbon dioxide from burning wood, in particular from forest fires in boreal and temperate regions resulting from both natural and man-made causes and predominantly from forest fires in tropical regions caused by shifting cultivation, is estimated to be 5.7 × 10
15
grams of carbon per year as gross input and 1.5 × 10
15
grams of carbon per year as net input. This is a significant amount as compared to the fossil fuel carbon dioxide produced from the utilization of oil, gas, coal, and limestone, and bears on the hypothesis of the enhanced sedimentation of marine detritus as a removal mechanism of excess atmospheric carbon dioxide.
Earthquakes, Faults, and Nuclear Power Plants in Southern New York and Northern New Jersey
Authors: Aggarwal Yash P. , Sykes Lynn R.
Published: October 2006

Seismic activity in the greater New York City area is concentrated along several northeast-trending faults of which the Ramapo fault appears to be the most active. Three nuclear power plants at Indian Point, New York, are situated close to the Ramapo fault. For a reactor site in use for 40 years, the probability that the site will experience an intensity equal to or in excess of the design (safe shutdown) earthquake is estimated to be about 5 to 11 percent.
Degraded Lignin Compounds Identified in Silicified Wood 200 Million Years Old
Authors: Sigleo Anne Colberg
Published: October 2006

Degraded lignin compounds have been identified in Triassic age (about 200 million years) silicified wood from the Petrified Forest National Park in Arizona. The pyrolysis products from black carbonaceous samples include carbon dioxide, low-molecular-weight alkanes and alkenes, benzene, alkyl-substituted benzenes, phenol, cresol, xylenols, indenes, benzofurans, trimethylindanone, and naphthalenes. These compounds are also the primary pyrolyzates of modern lignin above 500°C.
Chemosensory Grazing by Marine Calanoid Copepods (Arthropoda: Crustacea)
Authors: Poulet S. A. , Marsot P.
Published: October 2006

In laboratory experiments, mixed populations of two marine copepods (
Acartia clausi
and
Eurytemora herdmani
_ when fed artificial food particles consisting of microcapsules that were either enriched with an encapsulated homogenate of naturally occurring phytoplankton or nonenriched preferentially ingested the enriched capsules. Beads or nonenriched capsules were either seldom ingested or not ingested at all. The observations demonstrate that filter-feeding in these species is a behavioral process, under sensory control, and that the copepods are able to discriminate between enriched and nonenriched food particles.
Distinctive Cranial and Cervical Innervation of Wing Muscles: New Evidence for Bat Monophyly
Authors: Thewissen J. G. M. , Babcock S. K.
Published: October 2006

The traditional view that Old World fruit bats (Megachiroptera) and insect bats (Microchiroptera) are closely related has been challenged by claims that Megachiroptera are the sister group to flying lemurs (Dermoptera) or Primates. We found that the specialized muscles of the rostral part of the wing in Microchiroptera and Megachiroptera receive double innervation by both the facial nerve and cervical spinal nerves, suggesting that bats are monophyletic. Innervation by the facial nerve also occurs in Dermoptera and suggests that bats and Dermoptera share a common ancestor that had wings.
Diabetic Hyperglycemia: Link to Impaired Glucose Transport in Pancreatic β Cells
Authors: Unger Roger H.
Published: October 2006

Glucose uptake into pancreatic β cells by means of the glucose transporter GLUT-2, which has a high Michaelis constant, is essential for the normal insulin secretory response to hyperglycemia. In both autoimmune and nonautoimmune diabetes, this glucose transport is reduced as a consequence of down-regulation of the normal β-cell transporter. In autoimmune diabetes, circulating immunoglobulins can further impair this glucose transport by inhibiting functionally intact transporters. Insights into mechanisms of the unresponsiveness of β cells to hyperglycemia may improve the management and prevention of diabetes.
Proctodeal Feeding by Termitophilous Staphylinidae Associated with
Reticulitermes virginicus
(Banks)
Authors: Howard Ralph W.
Published: October 2006

Trichopsenius depressus
Le Conte,
Xenistusa hexagonalis
Seevers, and
Philotermes howardi
Kistner and Gut solicit and receive proctodeal and stomodeal fluids from their host, as well as engage in allogrooming with them. No other trophic behaviors were observed, suggesting that the beetles are completely integrated into the termite's trophic system.
Experiments with Controlled Langmuir Circulations
Authors: Faller Alan J.
Published: October 2006

Laboratory experiments in which wind was blown gently over a regular crossed-wave pattern have clearly shown the existence of regular, steady, and reproducible Langmuir circulations. The circulations were present only when both the wind and the wave patterns existed at the same time. With circulations having an across-wind wavelength of 44 centimeters, the descending vertical motions carried turbulent surface water downward 39 centimeters to the bottom of the wind and wave tank. The observations are in general agreement with the mathematical model of Craik and Leibovich, although further experiments will be required to definitively test the analytical model.
Geographical Trends in Numbers of Species
Authors: Schall Jos. J. , Pianka Eric R.
Published: October 2006

Geographic variation in the number of coexisting plant and animal species (species density) often follows repeated patterns; best known is the general increase in species richness from temperate to tropical latitudes. Here we undertake a quantitative analysis of geographic trends in species density for the terrestrial vertebrate faunas of the United States and Australia. Trends in numbers of species of amphibians, reptiles, birds, and mammals are described and are correlated with geographic variation in abiotic environmental measures. Intercontinental comparisons reveal general patterns as well as intriguing and profound differences in vertebrate distributions.
A Search for Ultra-Narrowband Signals of Extraterrestrial Origin
Authors: Horowitz Paul
Published: October 2006

Nearly 200 nearby stars similar to the sun were observed at the 21-centimeter neutral hydrogen wavelength (in the heliocentric frame) with a bandwidth of 1 kilohertz and a resolution of 0.015 hertz, using the Arecibo 305-meter antenna. At this resolution the effects of terrestrial interference are so slight that the detection limit of 4 × 10
–27
watt per square meter was set by receiver noise alone. No evidence of artificial signals was found.
Decomposition of Calcium Carbonate and Organic Carbon in the Deep Oceans
Authors: Chen Chen-Tung A.
Published: October 2006

Simple mass-balance calculations indicate that in seawater the calcium variation (ΔCa) correlates with the variation in the titration alkalinity (Δ
TA
) and the variation in the total carbon dioxide (ΔσCO
2
) or nitrate (ΔNO
3
) according to the equations ΔCa = 0.46288 Δ
TA
+ 0.074236 ΔσCO
2
and ΔCa = 0.5 Δ
TA
+ 0.53125 ΔNO
3
. The estimated values for ΔCa from these equations, which agree with the values obtained from direct measurements, have been used to estimate the ratio of the in situ inorganic to organic carbon fluxes in the oceans. The precise vertical distribution of this ratio is shown for the first time.
Technology Creep and the Arms Race: ICBM Problem a Sleeper
Authors: Shapley Deborah
Published: October 2006

In three articles,
Science
will discuss how the creep of technology affects the arms race. The first two articles will deal with the most important current example: first, how ICBM modernization is giving both sides a destabilizing, first-strike capability, and second, how arms control seems to be dealing inadequately with this pressing problem. The third article will describe other cases of incremental technical improvements affecting arms control, such as antisatellite research and ballistic missile defense research, which are bringing both sides closer to the antiballistic missile capability they forswore in a 1972 treaty.