bluuebunny/crossref_metadata_2025 huggingface dataset:
Postseismic Viscoelastic Rebound
Authors: Nur Amos , Mavko Gerald
Published: October 2006

The sudden appearance of a dislocation, representing an earthquake, in an elastic layer (the lithosphere) overriding a viscoelastic half space (the asthenosphere) is followed by time-dependent surface deformation, which is very similar to in situ postseismic deformation. The spectacular postseismic deformation following the large Nankaido earthquake of 1946 yields for the asthenosphere a viscosity of 5 × 10
19
poise and a 50 percent relaxation of the shear modulus. Large thrust type earthquakes may provide, in the future, a new method for exploring the rheology of the earth's upper mantle.
Pioneer 10 Observations of the Ultraviolet Glow in the Vicinity of Jupiter
Authors: Judge Darrell L. , Carlson Robert W.
Published: October 2006

A two-channel ultraviolet photometer aboard Pioneer 10 has made several observations of the ultraviolet glow in the wavelength range from 170 to 1400 angstroms in the vicinity of Jupiter. Preliminary results indicate a Jovian hydrogen (1216 angstrom) glow with a brightness of about 1000 rayleighs and a helium (584 angstrom) glow with a brightness of about 10 to 20 rayleighs. In addition, Jupiter appears to have an extensive hydrogen torus surrounding it in the orbital plane of Io. The mean diameter of the torus is about equal to the diameter of the orbit of Io. Several observations of the Galilean satellites have also occurred but only a rather striking Io observation has been analyzed to date. If the observed Io glow is predominantly that of Lyman-α, the surface brightness is about 10,000 rayleighs.
Preliminary Results on the Atmospheres of Io and Jupiter from the Pioneer 10 S-Band Occultation Experiment
Authors: Kliore Arvydas , Cain Dan L. , Fjeldbo Gunnar , Seidel Boris L. , Rasool S. I.
Published: October 2006

The preliminary analysis of data from the Pioneer 10 S-band radio occultation experiment has revealed the presence of an ionosphere on the Jovian satellite Io (JI) having an electron density peak of about 6 × 10
4
electrons per cubic centimeter at an altitude of approximately 60 to 140 kilometers. This suggests the presence of an atmosphere having a surface number density of about 10
10
to 10
12
per cubic centimeter, corresponding to an atmospheric surface pressure of between 10
-8
and 10
-10
bar, at or below the detection threshold of the Beta Scorpii stellar occultation. A measurement of the atmosphere of Jupiter was obtained down to the level of about 80 millibars, indicating a large temperature increase at about the 20 millibar level, which cannot be explained by the absorption of solar radiation by methane alone and can possibly be due to absorption by particulate matter.
Synaptic Transmission between Photoreceptors and Horizontal Cells in the Turtle Retina
Authors: Cervetto Luigi , Piccolino Marco
Published: October 2006

Low calcium, high magnesium, and cobalt hyperpolarize the horizontal cell membrane and suppress the response to light, but only partially affect the response of receptor cells. These observations are consistent with the interpretation that a depolarizing transmitter is released by photoreceptors in darkness. The hyperpolarizing response to light of the horizontal cells would then result from a reduction in the amount of transmitter released.
Proton Relaxation Rates of Water in Brain and Brain Tumors
Authors: Parrish Rob G. , Kurland Robert J. , Janese Woodrow W. , Bakay Louis
Published: October 2006

The distribution of relaxation rates of water in "normal" (autopsy) samples of canine and human brain shows considerable overlap with that for brain tumor samples. The following ranges of values for the spin-spin relaxation rates were observed: for normal brain gray matter, 8.6 to 11.3 sec
-1
(mean, 9.5 sec
-1
); for normal brain white matter, 13.3 to 15.7 sec
-1
(mean, 15.5 sec
-1
); for six types of malignant tumor, 4.8 to 13.4 sec
-1
(mean, 9.3 sec
-1
); for five types of benign tumor, 7.1 to 16.4 sec
-1
(mean, 11.5 sec
-1
). Spin-lattice relaxation rates showed a similar pattern. At least two nonexchanging water components with different relaxation rates were indicated by the analysis of the spin-spin relaxation measurements for the white matter samples.
Failure to Confirm Cyclic AMP as Second Messenger for Norepinephrine in Rat Cerebellum
Authors: Lake Norma , Jordan Larry M.
Published: October 2006

Microiontophoretic applications of adenosine 3′,5′-monophosphate (cyclic AMP) to spontaneously active, electrophysiologically identified Purkinje cells of the rat cerebellum failed to mimic the strong depressant action of norepinephrine on the same cells. These findings, in combination with a reevaluation of other studies, cast doubt on the hypothesis that cyclic AMP mediates the depressant actions of norepinephrine in the cerebellum.
Observations at Venus Encounter by the Plasma Science Experiment on Mariner 10
Authors: Bridge H. S. , Lazarus A. J. , Scudder J. D. , Ogilvie K. W. , Hartle R. E. , Asbridge J. R. , Bame S. J. , Feldman W. C. , Siscoe G. L.
Published: October 2006

Preliminary results from the rearward-looking electrostatic analyzer of the plasma science experiment during the Mariner 10 encounter with Venus are described. They show that the solar-wind interaction with the planet probably involves a bow shock rather than an extended exosphere, but that this is not a thin boundary at the point where it was crossed by Mariner 10. An observed reduction in the flux of electrons with energies greater than 100 electron volts is interpreted as evidence for some direct interaction with the exosphere. Unusual intermittent features observed downstream of the planet indicate the presence of a comet-like tail hundreds of scale lengths in length.
Thymocyte Expression of RAG-1 and RAG-2: Termination by T Cell Receptor Cross-Linking
Authors: Turka Laurence A. , Schatz David G. , Oettinger Marjorie A. , Chun Jerold J. M. , Gorka Carolyn , Lee Kelvin , McCormack Wayne T. , Thompson Craig B.
Published: October 2006

The expression of the V(D)J [variable (diversity) joining elements] recombination activating genes, RAG-1 and RAG-2, has been examined during T cell development in the thymus. In situ hybridization to intact thymus and RNA blot analysis of isolated thymic subpopulations separated on the basis of T cell receptor (TCR) expression demonstrated that both TCR
-
and TCR
+
cortical thymocytes express RAG-1 and RAG-2 messenger RNA's. Within the TCR
+
population, RAG expression was observed in immature CD4
+
CD8
+
(double positive) cells, but not in the more mature CD4
+
CD8
-
or CD4
-
CD8
+
(single positive) subpopulations. Thus, although cortical thymocytes that bear TCR on their surface continue to express RAG-1 and RAG-2, it appears that the expression of both genes is normally terminated during subsequent thymic maturation. Since thymocyte maturation in vivo is thought to be regulated through the interaction of the TCR complex with self major histocompatibility complex (MHC) antigens, these data suggest that signals transduced by the TCR complex might result in the termination of RAG expression. Consistent with this hypothesis, thymocyte TCR cross-linking in vitro led to rapid termination of RAG-1 and RAG-2 expression, whereas cross-linking of other T cell surface antigens such as CD4, CD8, or HLA class I had no effect.
The DNA Binding Arm of λ Repressor: Critical Contacts from a Flexible Region
Authors: Clarke Neil D. , Beamer Lesa J. , Goldberg Harry R. , Berkower Carol , Pabo Carl O.
Published: October 2006

Segments of protein that do not adopt a well-ordered conformation in the absence of DNA can still contribute to site-specific recognition of DNA. The first six residues (NH
2
-Ser
1
-Thr
2
-Lys
3
-Lys
4
-Lys
5
-Pro
6
-) of phage λ repressor are flexible but are important for site-specific binding. Low-temperature x-ray crystallography and codon-directed saturation mutagenesis were used to study the role of this segment. All of the functional sequences have the form [X]
1
-[X]
2
-[Lys or Arg]
3
-[Lys]
4
-[Lys or Arg]
5
-[X]
6
. A high-resolution (1.8 angstrom) crystal structure shows that Lys
3
and Lys
4
each make multiple hydrogen bonds with guanines and that Lys
5
interacts with the phosphate backbone. The symmetry of the complex breaks down near the center of the site, and these results suggest a revision in the traditional alignment of the six λ operator sites.
Clean Fuels from Coal Gasification
Authors: Squires Arthur M.
Published: October 2006

The quickest way to establish a visible new margin against energy demand is the historic producer serving small industry and gasifying Pennsylvania anthracite. In 2 years many producers could be in operation.

The quickest way to obtain significant supplies of "new" gas or oil is to retrofit existing electricity and industrial boilers for power or industrial gas. Important results could be achieved in 6 years.

Table 3 identifies development activities deserving high priority to speed the capture of gas and oil now burned in boilers, and to speed realization of the advantages of combined-cycle equipment running on coal.

Obviously, these activities are not enough. Many exciting and worthwhile concepts at various stages of development can furnish improved techniques for converting coal to pipeline gas and liquid fuels for the long run. Reviews of these concepts are available. I have neglected them in this article not to deny their importance but to stress the earlier opportunities from technology that is ready now, or nearly ready.

The oil and gas industries might well consider the historical progression from Wells Fargo to Western Union to American Telephone and Telegraph to Radio Corporation of America. These industries will miss the boat if they regard themselves simply as purveyors of their historical fuels and not as purveyors of clean energy. The gas industry especially will be in trouble if it lets its major industrial customers, such as steel and electricity, provide their own supplies of power and industrial gas.
New Evidence for the Antiquity of Man in North America Deduced from Aspartic Acid Racemization
Authors: Bada Jeffrey L. , Schroeder Roy A. , Carter George F.
Published: October 2006

Ages of several California Paleo-Indian skeletons have been deduced from the extent of aspartic acid racemization. These dates suggest that man was present in North America at least 50,000 years before the present.
Kaolinite Synthesis at 25°C
Authors: Hem J. D. , Lind C. J.
Published: October 2006

The addition of quercetin, an organic flavone (C
15
H
10
O
7
), to aqueous solutions containing silica and aluminum and adjusted to final
p
H's from 6.5 to 8.5 produced a 1 : 1 aluminosilicate precipitate which, after 6 to 16 months of aging in solution at 25°C, contained as much as 5 percent well-formed kaolinite plates. Similar solutions containing no organic material produced relatively amorphous precipitates with the same composition and stability (standard free energy of formation = -897 ± 1 kilocalories per mole) but with substantially smaller amounts of crystalline material even after 2 years of aging.
Latent Ganglionic Infection with Herpes Simplex Virus Types 1 and 2: Viral Reactivation in vivo after Neurectomy
Authors: Walz M. Antoinette , Price Richard W. , Notkins Abner Louis
Published: October 2006

Inoculation of the cornea, lip, or footpad of mice with herpes simplex virus type 1 resulted in a latent infection of the local sensory ganglia. Inoculation of the vagina and cervix with herpes simplex virus type 2, as well as type 1, also induced a latent ganglionic infection. With the use of sciatic nerve section as a stimulus, a reproducible model of viral reactivation in vivo was established.
Thyroid Hormone Action: In vitro Demonstration of Putative Receptors in Isolated Nuclei and Soluble Nuclear Extracts
Authors: Samuels Herbert H. , Tsai Jir S. , Casanova Juan
Published: October 2006

Saturable binding activities for triiodothyronine were demonstrated in vitro with isolated nuclei and soluble nuclear extracts of rat liver, kidney, and cultured GH
1
cells. The binding activity can be extracted from nuclei in soluble form with no significant change in hormone affinity and has properties of a nonhistone protein.
A Gene Encoding an Antigen Recognized by Cytolytic T Lymphocytes on a Human Melanoma
Authors: van der Bruggen P. , Traversari C. , Chomez P. , Lurquin C. , De Plaen E. , Van den Eynde B. , Knuth A. , Boon T.
Published: October 2006

Many human melanoma tumors express antigens that are recognized in vitro by cytolytic T lymphocytes (CTLs) derived from the tumor-bearing patient. A gene was identified that directed the expression of antigen MZ2-E on a human melanoma cell line. This gene shows no similarity to known sequences and belongs to a family of at least three genes. It is expressed by the original melanoma cells, other melanoma cell lines, and by some tumor cells of other histological types. No expression was observed in a panel of normal tissues. Antigen MZ2-E appears to be presented by HLA-A1; anti-MZ2-E CTLs of the original patient recognized two melanoma cell lines of other HLA-A1 patients that expressed the gene. Thus, precisely targeted immunotherapy directed against antigen MZ2-E could be provided to individuals identified by HLA typing and analysis of the RNA of a small tumor sample.
Brain Cells in Culture: Morphological Transformation by a Protein
Authors: Lim Ramon , Mitsunobu Katsusuke
Published: October 2006

One type of embryonic rat brain cell having an epithelioid morphology in the monolayer culture can be transformed by brain extract into cells having extensive processes resembling mature astrocytes. The transforming factor is a protein with a molecular weight of 350,000. A partially purified sample showed that it is active at a concentration as low as 1 × 10
-8
M
. The transforming activity is high in adult brains but low in embryonic brains and tumors of the nervous systems.
Preliminary Infrared Radiometry of the Night Side of Mercury from Mariner 10
Authors: Chase S. C. , Miner E. D. , Morrison D. , Mnch G. , Neugebauer G. , Schroeder M.
Published: October 2006

The infrared radiometer on Mariner 10 measured the thermal emission from the planet with a spatial resolution element as small as 40 kilometers in a broad wavelength band centered at 45 micrometers. The minimum brightness temperature (near local midnight) in these near-equatorial scans was 100°K. Along the track observed, the temperature declined steadily from local sunset to near midnight, behaving as would be expected for a homogeneous, porous material with a thermal inertia of 0.0017 cal cm
-2
sec
-½
°K
-1
, a value only slightly larger than that of the moon. From near midnight to dawn, however, the temperature fluctuated over a range of about 10°K, implying the presence of regions having thermal inertia as high as 0.003 cal cm
-2
sec-½ °K
-1
.
Magnetic Field Observations near Mercury: Preliminary Results from Mariner 10
Authors: Ness N. F. , Behannon K. W. , Lepping R. P. , Whang Y. C. , Schatten K. H.
Published: October 2006

Results are presented from a preliminary analysis of data obtained near Mercury on 29 March 1974 by the NASA-GSFC magnetic field experiment on Mariner 10. Rather unexpectedly, a very well-developed, detached bow shock wave, which develops as the super-Alfvnic solar wind interacts with the planet, has been observed. In addition, a magnetosphere-like region, with maximum field strength of 98 gammas at closest approach (704 kilometers altitude), has been observed, contained within boundaries similar to the terrestrial magnetopause. The obstacle deflecting the solar wind flow is global in size, but the origin of the enhanced magnetic field has not yet been uniquely established. The field may be intrinsic to the planet and distorted by interaction with the solar wind. It may also be associated with a complex induction process whereby the planetary interior-atmosphere-ionosphere interacts with the solar wind flow to generate the observed field by a dynamo action. The complete body of data favors the preliminary conclusion that Mercury has an intrinsic magnetic field. If this is correct, it represents a major scientific discovery in planetary magnetism and will have considerable impact on studies of the origin of the solar system.
Electrons and Protons Accelerated in Mercury's Magnetic Field
Authors: Simpson J. A. , Eraker J. H. , Lamport J. E. , Walpole P. H.
Published: October 2006

Fluxes of protons with energies of ∼ 550 kev and electrons with energies of ∼ 300 kev which exceed approximately 10
4
and 10
5
cm
-2
sec
-1
, respectively, have been discovered in the magnetosphere of Mercury. Electron fluxes > 10
3
cm
-2
sec
-1
also are observed in the outbound pass of the Mariner 10 spacecraft through the magnetosheath. The intensity versus time profiles of the particle fluxes in the magnetosphere appear with sudden onsets of ∼ 10
4
cm
-2
sec
-1
beginning at interplanetary background levels and persisting for times equivalent to their being distributed spatially over regions having a scale size comparable to the planetary radius. For a spectral form dJ/dE α E-γ, where J is the differential particle intensity and E is the kinetic energy, the typical values of γ are γ
p
= 5.5 for protons above 500 kev and γ
e
≥ 9 for electrons above 170 kev. Large coherent electron intensity oscillations (variations of factors of 10 to 100) have been discovered with characteristic periods of ∼ 6 seconds and with higher frequency components. In some cases proton bursts are found in phase with these oscillations. On the basis of the experimental evidence and a knowledge of the general magnetic field intensities and directions along the trajectory of Mariner 10 provided by the magnetic field observations, it is shown that the radiation events observed in the magnetosphere and magnetosheath are transient and are not interpretable in terms of stable trapped particle populations. Furthermore, experimental evidence strongly supports the view that the particles are impulsively accelerated and that the acceleration source is not more distant from the point of observation along lines of force than ∼ 8 × 10
3
to 16 × 10
3
kilometers (3 to 6.5 units of Mercury's radius). Candidates for the regions most likely to be sources of particle acceleration are discussed, namely, the magnetotail and the magnetosheath. It is pointed out that the phenomena discovered at Mercury will place more stringent conditions on allowed models for electron and proton acceleration than have heretofore been possible in studies within the earth's magnetosphere.
Adrenergic Innervation of the Parasympathetic Ciliary Ganglion in the Chick
Authors: Cantino Dario , Mugnaini Enrico
Published: October 2006

The chick ciliary ganglion receives a nonvascular sympathetic innervation in addition to the well-known cholinergic one; fluorescent, varicose adrenergic fibers form pericellular baskets. Adrenergic fibers were identified electron microscopically in ganglia fixed with potassium permanganate. The fibers degenerate after injection of 6-hydroxydopamine. No true synaptic relationships involving adrenergic varicosities and ganglion cells or cholinergic terminals were demonstrable. The distribution of the adrenergic fibers suggests a kind of "distance synapse" with the choroidal cells or with the preganglionic fibers (or both). The adrenergic innervation might provide a modulation of the cholinergic transmission.
Assembly of Chick Brain Tubulin onto Isolated Basal Bodies of
Chlamydomonas reinhardi
Authors: Snell W. J. , Dentler W. L. , Haimo L. T. , Binder L. I. , Rosenbaum J. L.
Published: October 2006

Basal bodies isolated from
Chlamydomonas reinhardi
will serve as initiation centers for the assembly of chick brain microtubule protein subunits (tubulin) into microtubules. The rate of microtubule assembly is tubulin-concentration dependent; this assembly occurs onto both distal and proximal ends of the basal body microtubules, with distal assembly greatly favored. In vitro assembly of brain tubulin also occurs onto the mid-lateral aspects of the basal bodies, presumably onto the fiber connecting the two basal bodies.
Energy, Manpower, and the Highway Trust Fund
Authors: Bezdek Roger , Hannon Bruce
Published: October 2006

If energy conservation were a goal of a federal budget policy maker, such conservation could be achieved by reinvesting the highway trust fund in any of several other alternative federal programs (except criminal justice), especially in railroad and mass transit construction and national health insurance. Total employment would increase in each alternative program examined. For example, if construction monies were shifted from highways to railroads, the energy required for construction would be reduced by about 62 percent and employment would increase by 3.2 percent.

By comparing the dollar, energy, and employment requirements of a highway transportation system with such requirements for a railroad transportation system, we obtained detailed information from which we concluded the following:

1) Passenger transport by railroad was much less dollar and energy demanding and required more labor than car transport in 1963. If the dollar savings had been respent in an average way by consumers, the net impact would have been to reduce the energy savings and further increase employment. A similar conclusion was reached in a study of bus substitution for automobiles in urban areas. If the marginal substitution effects would have held over the whole range of change, and the dollar savings had been spent on the construction of railways, then about 3.0 billion gallons of gasoline could have been saved annually and 1.2 million new jobs created.

2) Freight transport by railroad was less expensive, in terms of dollar, energy, and labor requirements, than was truck transportation in 1963. If, under a national shift to rail freight, the dollar savings had been absorbed as personal consumption expenditures, a net increase of labor and energy would have ensued. If the dollar savings had been absorbed as a tax and respent on railroad and mass transit construction, about 0.3 billion more gallons of gasoline (energy equivalent) would have been consumed annually and 1.2 million jobs created, under a complete shift to rail.

Had there been a full shift from intercity car and truck transportation to transportation by railroad with dollar savings spent on railway construction, 2.7 billion gallons of gasoline (energy equivalent) could have been saved and 2.4 million new jobs could have been created in 1963.
Glacial Migrations of Plants: Island Biogeographical Evidence
Authors: Simpson Beryl B.
Published: October 2006

Analyses of the floras of the high north Andean habitat islands (paramos) and the Galpagos Islands show that plant species diversity conforms to the MacArthur and Wilson model of island biogeography but that immigration occurred primarily during glacial periods. Modern plant species diversity is more significantly correlated with area and distance measures of the glacial forms of the islands than with similar measures of the present-day islands.
Aglomerularism in Antarctic Fish
Authors: Dobbs Gary H. , Lin Yuan , DeVries Arthur L.
Published: October 2006

Urine formation in antarctic bony fish does not involve glomerular filtration. Evidence for aglomerularism came from both direct observation of kidney serial sections by light microscopy and the low concentrations of inulin labeled with carbon-14 that were excreted into the urine when this renal clearance tracer was injected into the bloodstream via a cannula implanted in the caudal vein. Aglomerularism most likely prevents urinary loss of glycoproteins with biological antifreeze properties.
Amino Acid Difference Formula to Help Explain Protein Evolution
Authors: Grantham R.
Published: October 2006

A formula for difference between amino acids combines properties that correlate best with protein residue substitution frequencies: composition, polarity, and molecular volume. Substitution frequencies agree much better with overall chemical difference between exchanging residues than with minimum base changes between their codons. Correlation coefficients show that fixation of mutations between dissimilar amino acids is generally rare.
Secular Variations in the Abundances of Heavy Nuclei in Cosmic Rays
Authors: Bhandari Narendra , Padia J. T.
Published: October 2006

The ratios of fluxes of heavy cosmic-ray nuclei [(30 ≤
Z
≤ 40)/(20 <
Z
≤ 28), where
Z
is the atomic number], based on studies of meteorites and lunar samples, show little variation with time, distance in the solar system (1 to 3 astronomical units), or kinetic energy (30 to 2000 megaelectron volts per nucleon). Samples exposed for time intervals of 10
3
to 10
8
years show that the variations in the flux of 30 ≤
Z
≤ 40 nuclei relative to that of the iron group nuclei (20 <
Z
≤ 28) have remained within the range of (1.3 ± 0.6) × 10
-3
during the last billions of years, thus indicating a remarkable similarity in the elemental composition of sources responsible for these nuclei in the cosmic radiation.
Atomic Images by Electron-Wave Holography
Authors: Bartell L. S. , Ritz C. L.
Published: October 2006

Direct views of electron clouds in atoms have been observed visually and photographed by means of a two-stage holographic microscope based on Gabor's principle of image reconstruction. Holograms are produced with 40-kilovolt electron radiation and decoded with an optical laser. The obviation of an objective lens makes feasible a numerical aperture of 0.37 and a resolving power exceeding 0.1 angstrom.
A Method to Identify Protein Sequences That Fold into a Known Three-Dimensional Structure
Authors: Bowie James U. , Lüthy Roland , Eisenberg David
Published: October 2006

The inverse protein folding problem, the problem of finding which amino acid sequences fold into a known three-dimensional (3D) structure, can be effectively attacked by finding sequences that are most compatible with the environments of the residues in the 3D structure. The environments are described by: (i) the area of the residue buried in the protein and inaccessible to solvent; (ii) the fraction of side-chain area that is covered by polar atoms (O and N); and (iii) the local secondary structure. Examples of this 3D profile method are presented for four families of proteins: the globins, cyclic AMP (adenosine 3′,5′-monophosphate) receptor-like proteins, the periplasmic binding proteins, and the actins. This method is able to detect the structural similarity of the actins and 70- kilodalton heat shock proteins, even though these protein families share no detectable sequence similarity.
Interspecies Conversion of
Clostridium botulinum
Type C to
Clostridium novyi
Type A by Bacteriophage
Authors: Eklund M. W. , Poysky F. T. , Meyers J. A. , Pelroy G. A.
Published: October 2006

When
Clostridium botulinum
type C is cured of its prophage it simultaneously ceases to produce toxin. This nontoxigenic culture can then be converted to another toxigenic bacterial species,
Clostridium novyi
type A or to toxigenic
Clostridium botulinum
types C or D, by specific bacteriophages. The toxigenicity and type of toxin produced by these cultures depends upon the continued presence of these bacteriophages.
Manganese and Biotic Debris Associations in Some Deep-Sea Sediments
Authors: Greenslate J.
Published: October 2006

Incipient manganese concretions occur in microcavities of planktonic skeletal debris (especially diatom frustules) in some Pacific Basin deep-sea sediments. These concretions contain over 50 percent manganese and very little iron (< 1 percent). There is a continuum of growth stages in the concretions having a diameter between 0 and approximately 2 millimeters, and a genetic relationship is suggested between the very small and the centimeter sized concretions.
Biological Populations with Nonoverlapping Generations: Stable Points, Stable Cycles, and Chaos
Authors: May Robert M.
Published: October 2006

Some of the simplest nonlinear difference equations describing the growth of biological populations with nonoverlapping generations can exhibit a remarkable spectrum of dynamical behavior, from stable equilibrium points, to stable cyclic oscillations between 2 population points, to stable cycles with 4, 8, 16, . . . points, through to a chaotic regime in which (depending on the initial population value) cycles of any period, or even totally aperiodic but bounded population fluctuations, can occur. This rich dynamical structure is overlooked in conventional linearized analyses; its existence in such fully deterministic nonlinear difference equations is a fact of considerable mathematical and ecological interest.
Lunar Magnetic Field: Permanent and Induced Dipole Moments
Authors: Russell C. T. , Coleman P. J. , Schubert G.
Published: October 2006

Apollo 15 subsatellite magnetic field observations have been used to measure both the permanent and the induced lunar dipole moments. Although only an upper limit of 1.3 × 10
18
gauss-cubic centimeters has been determined for the permanent dipole moment in the orbital plane, there is a significant induced dipole moment which opposes the applied field, indicating the existence of a weak lunar ionosphere.
Modeling Periodically Surging Glaciers
Authors: Budd W. F. , McInnes B. J.
Published: October 2006

A numerical model has been developed which produces periodic surging as a characteristic of some glaciers for a certain accumulation and bedrock distribution in contrast to the normal steady state for nonsurging glaciers. Results are presented to illustrate how the magnitude of changes in the length, thickness, and velocity of surging glaciers can be simulated by the model.
Target Structure and Echo Spectral Discrimination by Echolocating Bats
Authors: Simmons J. A. , Lavender W. A. , Lavender B. A. , Doroshow C. A. , Kiefer S. W. , Livingston R. , Scallet A. C. , Crowley D. E.
Published: October 2006

Echolocating bats can use sonar to discriminate among targets which reflect echoes differing in spectral distribution of energy but not in overall intensity. They can detect differences smaller than 1 millimeter in fine target structure. Bats may be capable of classifying targets from echo spectral signatures and might thus be able to distinguish among flying insect prey by sonar.
Structure of a Peptide Inhibitor Bound to the Catalytic Subunit of Cyclic Adenosine Monophosphate-Dependent Protein Kinase
Authors: Knighton Daniel R. , Zheng Jianhua , Ten Eyck Lynn F. , Xuong Nguyen-huu , Taylor Susan S. , Sowadski Janusz M.
Published: October 2006

The structure of a 20-amino acid peptide inhibitor bound to the catalytic subunit of cyclic AMP-dependent protein kinase, and its interactions with the enzyme, are described. The x-ray crystal structure of the complex is the basis of the analysis. The peptide inhibitor, derived from a naturally occurring heat-stable protein kinase inhibitor, contains an amphipathic helix that is followed by a turn and an extended conformation. The extended region occupies the cleft between the two lobes of the enzyme and contains a five-residue consensus recognition sequence common to all substrates and peptide inhibitors of the catalytic subunit. The helical portion of the peptide binds to a hydrophobic groove and conveys high affinity binding. Loops from both domains converge at the active site and contribute to a network of conserved residues at the sites of magnesium adenosine triphosphate binding and catalysis. Amino acids associated with peptide recognition, nonconserved, extend over a large surface area.
Microwave Emission Spectrum of the Moon: Mean Global Heat Flow and Average Depth of the Regolith
Authors: Keihm Stephen J. , Langseth Marcus G.
Published: October 2006

Earth-based observations of the lunar microwave brightness temperature spectrum at wavelengths between 5 and 500 centimeters, when reexamined in the light of physical property data derived from the Apollo program, tentatively support the high heat flows measured in situ and indicate that a regolith thickness between 10 and 30 meters may characterize a large portion of the lunar near side.
Enzymatic Characterization of Soluble Organic Phosphorus in Lake Water
Authors: Herbes Stephen E. , Allen Herbert E. , Mancy Khalil H.
Published: October 2006

Although the concentration of soluble organic phosphorus in lake water often exceeds that of orthophosphate severalfold, little is known of its composition. By using enzyme assays it was determined that up to 50 percent of the organic fraction is hydrolyzable by phytase. The enzymatically degradable material consists of both low and high molecular weight fractions.
Energy Conservation Policies of the Federal Energy Office: Economic Demand Analysis
Authors: Ferrar Terry A. , Nelsona Jon P.
Published: October 2006

Forecasts for crude petroleum consumption are presented which take into account attempts by the Federal Energy Office to regulate residential and commercial thermostats. On the basis of an economic demand model, it is found that lowering all thermostats by 6°F would lower the projected residential and commercial petroleum demand in 1973 by 12 percent. This amount is compared to forecasts made by the Federal Energy Office and to the effect of a price increase of $0.10 per gallon for heating oil.
Technology Utilization: Incentives and Solar Energy
Authors: Ezra Arthur A.
Published: October 2006

If the federal government is not going to be the major market for the application of federally funded R & D results, then the responsibility for bringing about technology utilization cannot be borne alone by the federal agency funding the R & D. That this problem is now being recognized is shown by the number of bills that were introduced in Congress in 1974, culminating in the Solar Heating and Cooling Act of 1974.

An examination of the incentives for technology utilization in the conceptual framework of TDS reveals the following:

1) Incentives must be applied to each component of the TDS.

2) Different components in the TDS require different incentives.

3) Although information exists concerning a wide variety of incentives that are currently being used by various federal agencies to stimulate technology utilization, most of this information is in the form of raw data compiled by the respective agencies and a substantial effort will be required to collect, compile, and evaluate them.

4) All the components of a TDS must be activated if technology utilization is to occur on a self-sustaining basis. This makes experimental verification of a particular incentive on a particular component difficult.

5) A federal agency concerned with technology utilization can and should assume the responsibility for identifying all the components of the required TDS, devising incentives for each component and testing them to ensure their effectiveness. Where a TDS does not exist, the federal agency may have to assume the responsibility of creating one. The scope of this effort in many cases may transcend the present authority of the agency, and congressional action may be required to remedy this shortcoming.
Primate Predation: Interim Report on the Development of a Tradition in a Troop of Olive Baboons
Authors: Strum S. C.
Published: October 2006

A troop of olive baboons,
Papio anubis
, has developed systematic predation, which includes hunting and sharing of meat. Although meat-eating among nonhuman primates—baboons and chimpanzees especially—had been discovered in earlier field studies, systematic predation had been reported for chimpanzees and humans only. Starting as an adult male activity in the olive baboon troop, this tradition rapidly expanded to include capture and consumption of prey by adult females and juveniles of all ages and both sexes. Infants eat but have not been observed to capture prey.
Evidence of Lactate Dehydrogenase-b Allozyme Effects in the Teleost,
Fundulus heteroclitus
Authors: DiMichele Leonard , Paynter Kennedy T. , Powers Dennis A.
Published: October 2006

The evolutionary significance of protein polymorphisms has long been debated. Exponents of the balanced theory advocate that selection operates to maintain polymorphisms, whereas the neoclassical school argues that most genetic variation is neutral. Some studies have suggested that protein polymorphisms are not neutral, but their significance has been questioned because one cannot eliminate the possibility that linked loci were responsible for the observed differences. Evidence is presented that an enzymatic phenotype can affect carbon flow through a metabolic pathway. Glucose flux differences between lactate dehydrogenase-B phenotypes of
Fundulus heteroclitus
were reversed by substituting the
Ldh-B
gene product of one homozygous genotype with that of another.
Management of Famine Relief
Authors: Mayer Jean
Published: October 2006

We have, over the course of time, made discoveries in compassion as well as discoveries in technology. Many problems that had been judged insoluble in the past are no longer tolerable. For many centuries, starvation was inevitable, largely because means of information and means of transportation were not at hand; the fact that there usually was more food available somewhere else on the same or another continent was irrelevant. There was no way of hearing of the famine, bringing the food where it was needed, or distributing it. We now have the knowledge to install early warning systems based on economic and on medical surveillance. Such data as weather reports, crop forecasts, food reserves and retail prices, height-to-weight ratios, skin fold thicknesses, and height-to-arm circumference ratios in children can warn us in advance of impending famine. We also now have the means to transport the food to the area of threatening or actual mass starvation. Therefore, we have obligations that did not exist in past generations. We are now also in a much smaller world from which some of our contemporaries have stepped out to look at the spaceship on which we are all traveling. The worldwide civil rights revolution of the 1960's has brought about greater realization that all human beings are born equal and must be preserved and helped. All this means not only that we must organize to prevent famines on a worldwide basis, but also that we must use the most modern technology to do so. The fact that famine often occurs in remote areas is no reason why we cannot use computers and other modern technology. The very need for programming computers, with the planned coding and feeding of data that it entails, not only forces preparedness but also obliges planners to examine responses to various contingencies. National and international training courses for policymakers and managers of famine relief should follow.

Even if mankind brings its resources and its population into balance, a sound organization of famine relief preparation will still be needed to cope with local contingencies. Rapid agricultural advancement, development of innovative food sources, and, above all, control of population growth are necessary if famine is not to stalk all of mankind in the future.
Pulsars and High Density Physics
Authors: Hewish A.
Published: October 2006

In outlining the physics of neutron stars, and my good fortune in stumbling upon them, I hope that I have given some idea of the interest and rewards of extending physics beyond the confines of laboratories. These are good times in which to be an astrophysicist. I am also deeply aware of my debt to all my colleagues in the Cavendish Laboratory. Firstly to Sir Martin Ryle for his unique flair in creating so congenial and stimulating a team in which to work. Secondly to Jocelyn Bell for the care, diligence, and persistence that led to our discovery so early in the scintillation program, and finally to my friends who contributed so generously in many aspects of the work.
High-Field
13
C NMR Studies of Certain Normal and Abnormal Human Plasma Lipoproteins
Authors: Hamilton J. A. , Oppenheimer N. J. , Addleman R. , Clouse A. O. , Cordes E. H. , Steiner P. M. , Glueck C. J.
Published: October 2006

High-field (63.4 kilogauss) Fourier transform nuclear magnetic resonance spectroscopy of
13
C in natural abundance has been used to study the structural organization and molecular dynamics of constituent lipids of normal human very-low-density lipoproteins (VLDL) and low-density lipoproteins (LDL). The same method was used to study the abnormal β-VLDL of two type III hyperlipoproteinemia patients having markedly differing ratios of VLDL cholesterol to triglyceride (0.3 and 0.6, respectively). Resolution obtained at 63.4 kilogauss has made possible the assignment of several additional resonances of cholesterol ring carbon atoms, not resolved in earlier studies at lower fields, in the VLDL spectra. The rotational reorientation of the ring portion of cholesteryl esters in VLDL (normal) and β-VLDL (abnormal) is not highly anisotropic and is similar to that for cholesteryl esters dissolved in excess triolein. The rotations of cholesteryl esters in LDL are more highly anisotropic and significantly more restricted. The results suggest that the structural organization of the lipid components in β-VLDL resembles that found in normal VLDL but differs significantly from that for normal LDL.
Spatial Scales of Current Speed and Phytoplankton Biomass Fluctuations in Lake Tahoe
Authors: Powell Thomas M. , Richerson Peter J. , Dillon Thomas M. , Agee Bruce A. , Dozier Barton J. , Godden Daniel A. , Myrup Leonard O.
Published: October 2006

Spectral analysis of current speed and chlorophyll a measurements in Lake Tahoe, California and Nevada, indicates that considerably more variance exists at longer length scales in chlorophyll than in the current speeds. Increasingly, above scales of approximately 100 meters, chlorophyll does not behave as a simple passive contaminant distributed by turbulence, which indicates that biological processes contribute significantly to the observed variance at these large length scales.
Concurrent Processing and Complexity of Temporally Encoded Neuronal Messages in Visual Perception
Authors: McClurkin John W. , Optican Lance M. , Richmond Barry J. , Gawne Timothy J.
Published: October 2006

The intrinsic neuronal code that carries visual information and the perceptual mechanism for decoding that information are not known. However, multivariate statistics and information theory show that neurons in four visual areas simultaneously carry multiple, stimulus-related messages by utilizing multiplexed temporal codes. The complexity of these temporal messages increases progressively across the visual system, yet the temporal codes overlap in time. Thus, visual perception may depend on the concurrent processing of multiplexed temporal messages from all visual areas.
Microwave Measurement of Mesospheric Carbon Monoxide
Authors: Waters J. W. , Wilson W. J. , Shimabukuro F. I.
Published: October 2006

Ground-based observation of atmospheric absorption of solar radiation at a wavelength of 2.6 millimeters has provided the first measurement of mesospheric carbon monoxide. The measurement agrees with photochemical predictions of a carbon monoxide source in the lower thermosphere due to dissociation of carbon dioxide by solar radiation, and has implications for the magnitude of vertical transport in the mesosphere.
Aseismic Uplift in Southern California
Authors: Castle Robert O. , Church Jack P. , Elliott Michael R.
Published: October 2006

Preliminary examination of the historic geodetic record has disclosed crustal uplift of 0.15 to 0.25 meter that apparently began around 1960 and has since grown to include at least 12,000 square kilometers of southern California. This uplift extends at least 150 kilometers west-northwestward along the San Andreas Fault from Cajon to Maricopa, southward from the San Andreas into the northern Transverse Ranges, and eastward from Lebec into and including much of the western Mojave block. It seems to have grown spasmodically eastward from a center near the junction of the San Andreas and Garlock faults and has occurred largely within an area that has remained virtually aseismic since at least 1932. Although much of this area has been characterized by crustal mobility since at least the turn of the century, the described uplift seems to be an unusually large and probably unique event superimposed on the existing pattern of continuing deformation.
Leaf Pubescence: Effects on Absorptance and Photosynthesis in a Desert Shrub
Authors: Ehleringer James , Björkman Olle , Mooney Harold A.
Published: October 2006

The presence of leaf pubescence (leaf hairs) in
Encelia farinosa
, a desert species of the Composite family, reduces the absorptance of photosynthetically active radiation (400 to 700 nanometers) by as much as 56 percent more than a closely related but nonpubescent species,
E. californica
, a native of the relatively moist southern California coast. Pubescence in
E. farinosa
, which increases through the growing season, modifies the leaf energy balance and dramatically reduces the photosynthetic rate. The reduction in the photosynthetic rate is caused by decreased light absorption rather than decreased carbon dioxide conductance through the boundary layer.
Supershrimp: Deep Bioturbation in the Strait of Canso, Nova Scotia
Authors: Pemberton George S. , Risk Michael J. , Buckley Dale E.
Published: October 2006

Axius serratus
, a crustacean thought to be extremely rare, was discovered in large numbers in polluted regions of the Strait of Canso. The shrimp may live deeper than 3 meters in the sediment; burrows are kept open to at least 2.5 meters. Sediment contained in old filled burrows is anomalous in its distribution of particle size and its content of water, organic carbon, and trace elements. These anomalous qualities affect the geotechnical properties of sediments on the sea floor.
Energy Use in Rural India
Authors: Revelle Roger
Published: October 2006

An old saying has it, "slavery will persist until the loom weaves itself." All ancient civilizations, no matter how enlightened or creative, rested on slavery and on grinding human labor, because human and animal muscle power were the principal forms of energy available for mechanical work. The discovery of ways to use less expensive sources of energy than human muscles made it possible for men to be free. The men and women of rural India are tied to poverty and misery because they use too little energy and use it inefficiently, and nearly all they use is secured by their own physical efforts. A transformation of rural Indian society could be brought about by increasing the quantity and improving the technology of energy use.
Aluminum-26 in Deep-Sea Sediment
Authors: Reyss J. L. , Yokoyama Y. , Tanaka S.
Published: October 2006

The activity of
26
Al in a North Pacific core was found to be 0.081 ± 0.046 disintegration per minute per kilogram of dry sediment, which corresponds to a
26
Al/
10
Be ratio of 0.018 ± 0.011 (or 0.019 ± 0.012 when this ratio is corrected for decay). This ratio is in good agreement with that measured in Greenland ice, 0.017 ± 0.008. These ratios are also in agreement with the calculated values for the production of these isotopes by cosmic rays in the atmosphere: 0.013 ± 0.006. The contribution of cosmic dust bearing
26
Al seems small in comparison with the production of this nuclide in the atmosphere.
Search for Organic and Volatile Inorganic Compounds in Two Surface Samples from the Chryse Planitia Region of Mars
Authors: Biemann K. , Oro J. , Toulmin P. , Orgel L. E. , Nier A. O. , Anderson D. M. , Simmonds P. G. , Flory D. , Diaz A. V. , Rushneck D. R. , Biller J. A.
Published: October 2006

Two surface samples collected from the Chryse Planitia region of Mars were heated to temperatures up to 500°C, and the volatiles that they evolved were analyzed with a gas chromatograph-mass spectrometer. Only water and carbon dioxide were detected. This implies that organic compounds have not accumulated to the extent that individual components could be detected at levels of a few parts in 10
9
by weight in our samples. Proposed mechanisms for the accumulation and destruction of organic compounds are discussed in the light of this limit.