bluuebunny/crossref_metadata_2025 huggingface dataset:
Ocean Tide and Waves Beneath the Ross Ice Shelf, Antarctica
Authors: Williams Richard T. , Robinson Edwin S.
Published: October 2006

The ocean tide in the southern Ross Sea is principally diurnal. The tropic tide range (double amplitude) is between 1 and 2 meters, depending on the location, and is closely related to the local water-layer thickness. The range of the tropic tide is more than three times the range of the equatorial tide. Cotidal and coamplitude charts were made for the largest diurnal constituents,
K
1
and
O
1
and a provisional cotidal map was made for the semidiurnal constituent
M
2
. The amplitudes of the diurnal tide constituents are larger in the Ross Sea than in the adjacent southern Pacific Ocean, indicating the existence of a diurnal resonance related to the shape and depth of the sea. Waves related to ocean swell propagate into the ice-covered region from the northern Ross Sea. These waves have amplitudes near 1 centimeter, and periods in the range 1 to 15 minutes. The speed at which these waves travel is successfully predicted by flexural wave theory.
Initial Observations of the Pioneer Venus Orbiter Solar Wind Plasma Experiment
Authors: Wolfe J. , Intriligator D. S. , Mihalov J. , Collard H. , McKibbin D. , Whitten R. , Barnes A.
Published: October 2006

Initial results of observations of the solar wind interaction with Venus indicate that Venus has a well-defined, strong, standing bow shock wave. Downstream from the shock, an ionosheath is observed in which the compressed and heated postshock plasma evidently interacts directly with the Venus ionosphere. Plasma ion velocity deflections observed within the ionosheath are consistent with flow around the blunt shape of the ionopause. The ionopause boundary is observed and defined by this experiment as the location where the ionosheath ion flow is first excluded. The positions of the bow shock and ionopause are variable and appear to respond to changes in the external solar wind pressure. Near the terminator the bow shock was observed at altitudes of ∼4600 to ∼12,000 kilometers. The ionopause altitude ranged from as low as ∼450 to ∼1950 kilometers. Within the Venus ionosphere low-energy ions (energy per unit charge < 30 volts) were detected and have been tentatively identified as nonflowing ionospheric ions incident from a direction along the spacecraft velocity vector.
Minor Planets: The Discovery of Minor Satellites
Authors: Binzel R. P. , Van Flandern T. C.
Published: October 2006

The recent confirmation of the discovery of a satellite of the minor planet 532 Herculina indicates that other similar anomalous sightings are probably also due to satellites, which must therefore be numerous and commonplace. There are now 23 candidate satellites for eight minor planets, and no one of these minor planets occulting a star has failed to show evidence of at least one secondary event. Such companions are gravitationally stable but apparently have rapid tidal evolution rates.
The Estuarine Surface Microlayer and Trace Metal Cycling in a Salt Marsh
Authors: Pellenbarg Robert E. , Church Thomas M.
Published: October 2006

The aqueous surface microlayer in a Delaware salt marsh carries an average of 10 percent of the copper, 19 percent of the zinc, and 23 percent of the iron relative to the total metal flux including the dissolved and seston components. Such trace metals cycle in the salt marsh by net import on the surface microlayer and net export in the dissolved and seston components during maximum monthly tides.
Mobilizing Technology for Developing Countries
Authors: Weiss Charles
Published: October 2006

A new problem in technology policy—a discipline hitherto largely concerned with the modern industrial sector—is posed by the need for technology suited to creating productive jobs and providing minimum public services at a cost and level of sophistication within the reach of poor people in developing countries. Careful consideration must be given to overall and sectoral development objectives, economic and manpower resources, and the local institutional and sociocultural context. This may indicate the need for both hardware innovation, such as low-cost alternatives to waterborne sewerage, and social ("software") innovation, such as training large numbers of supervisors to implement improved technologies for labor-intensive civil works.
Acid Rain: Neutralization Within the Hubbard Brook Ecosystem and Regional Implications
Authors: Johnson Noye M.
Published: October 2006

The neutralization of strong acids from precipitation is largely accomplished (75 percent) in the soil zone by rapid reaction with basic aluminum salts and biologic matter. On a regional basis, acidified and aluminum-rich lakes and streams in New England are confined mainly to low-order watersheds.
Radio Science with Voyager 1 at Jupiter: Preliminary Profiles of the Atmosphere and Ionosphere
Authors: Eshleman V. R. , Tyler G. L. , Wood G. E. , Lindal G. F. , Anderson J. D. , Levy G. S. , Croft T. A.
Published: October 2006

A preliminarv profile of the atmosphere of Jupiter in the South Equatorial Belt shows (i) the tropopause occurring at a pressure level of 100 millibars and temperature of about 113K, (ii) a higher warm inversion layer at about the 35-millibar level, and (iii) a lower-altitude constant lapse rate matching the adiabatic value of about 2 K per kilometer, with the temperature reaching 150 K at the 600-millibar level. Preliminary afternoon and predawn ionospheric profiles at 12° south latitude and near the equator, respectively, have topside plasma scale heights of 590 kilometers changing to 960 kilometers above an altitude of 3500 kilometers for the dayside, and about 960 kilometers at all measured heights above the peak for the nightside. The higher value of scale height corresponds to a plasma temperature of 1100 K under the assumption of a plasma of protons and electrons in ambipolar diffusive equilibrium. The peak electron concentration in the upper ionosphere is approximately 2 × 10
5
per cubic centimeter for the dayside and about a factor of 10 less for the nightside. These peaks occur at altitudes of 1600 and 2300 kilometers, respectively. Continuing analyses are expected to extend and refine these results, and to be used to investigate other regions and phenomena.
Dark Anaerobic Dinitrogen Fixation by a Photosynthetic Microorganism
Authors: Madigan Michael T. , Wall Judy D. , Gest Howard
Published: October 2006

Photosynthetic purple bacteria can grow with dinitrogen gas as the sole nitrogen source under anaerobic conditions with light as the energy source. The bacterium
Rhodopseudomonas capsulata
can fix nitrogen in darkness with alternative energy conversion systems, namely, anaerobic sugar fermentation and aerobic respiration at low oxygen tension. Although growth on dinitrogen is optimal under photosynthetic conditions, the results show that reduction of dinitrogen is not obligatorily coupled to activity of the photosynthetic apparatus.
Opiate Receptors for Behavioral Analgesia Resemble Those Related to the Depression of Spinal Nociceptive Neurons
Authors: Yaksh Tony L.
Published: October 2006

With naloxone as antagonist, a dose-ratio analysis of the depression by morphine of nociceptive neurons in the spinal cord reveals that this opiate depression of single unit activity has the same pharmacological properties as observed with morphine analgesia. This suggests that the opiate receptor, mediating the observed cellular depression, and those mediating analgesia are presumably the same.
Reliability of Minor Planet Satellite Observations
Authors: Reitsema Harold J.
Published: October 2006

In an examination of the reliability of occultation observations of minor planet companions, redundant photoelectric observations have been made of possible occultation events. These observations indicate that spurious events may be easily misidentified as true occultations, and that caution must be exercised in interpreting such occurrences. Further analysis of observations of the 1973 Pallas occultation suggests that earlier results may be unreliable.
Discovery of a New Jupiter Satellite
Authors: Jewitt David C. , Danielson G. Edward , Synnott Stephen P.
Published: October 2006

During detailed analysis of Voyager 2 pictures of the Jupiter ring, a starlike object was identified in the plane of the ring. The same object was subsequently found on a higher-resolution frame and proved to be a satellite of Jupiter. This satellite has a circular orbit whose radius is 1.8 Jupiter radii, a period of 7 hours and 8 minutes, and a diameter of less than 40 kilometers. It is located at the outer edge of the Jupiter ring.
Vertical Structure of the Ionosphere and Upper Neutral Atmosphere of Saturn from the Pioneer Radio Occultation
Authors: Kliore Arvydas J. , Lindal Gunnar F. , Patel Indu R. , Sweetnam Donald N. , Hotz Henry B. , McDonough Thomas R.
Published: October 2006

Radio occultation measurements at S band (2.293 gigahertz) of the ionosphere and upper neutral atmosphere of Saturn were obtained during the flyby of the Pioneer 11 Saturn spacecraft on 5 September 1979. Preliminary analysis of the occultation exit data taken at a latitude of 9.5°S and a solar zenith angle of 90.6° revealed the presence of a rather thin ionosphere, having a main peak electron density of about 9.4 × 10
3
per cubic centimeter at an altitude of about 2800 above the level of a neutral number density of 10
19
per cubic centimeter and a lower peak of about 7 × 10
3
per cubic centimeter at 2200 kilometers. Data in the neutral atmosphere were obtained to a pressure level of about 120 millibars. The temperature structure derived from these data is consistent with the results of the Pioneer 11 Saturn infrared radiometer experiment (for a helium fraction of 15 percent) and with models derived from Earth-based observations for a helium fraction by number of about 4 to 10 percent. The helium fraction will be further defined by mutual iteration with the infrared radiometer team.
Pioneer Saturn Celestial Mechanics Experiment
Authors: Anderson John D. , Null George W. , Biller Elinor D. , Wong Sun Kuen , Hubbard William B. , MacFarlane Joseph J.
Published: October 2006

During the Pioneer Saturn encounter, a continuous round-trip radio link at S band (∼ 2.2 gigahertz) was maintained between stations of the Deep Space Network and the spacecraft. From an analysis of the Doppler shift in the radio carrier frequency, it was possible to determine a number of gravitational effects on the trajectory. Gravitational moments (
J
2
and
J
4
) for Saturn have been determined from preliminary analysis, and preliminary mass values have been determined for the Saturn satellites Rhea, Iapetus, and Titan. For all three satellites the densities are low, consistent with the compositions of ices. The rings have not been detected in the Doppler data, and hence the best preliminary estimate of their total mass is zero with a standard error of 3 × 10
–6
Saturn mass. New theoretical calculations for the Saturn interior are described which use the latest observational data, including Pioneer Saturn, and state-of-the-art physics for the internal composition. Probably liquid H
2
O and possibly NH
3
and CH
4
are primarily confined in Saturn to the vicinity of a core of approximately 15 to 20 Earth masses. There is a slight indication that helium may likewise be fractionated to the central regions.
Volcanic Contribution of Chlorine to the Stratosphere: More Significant to Ozone Than Previously Estimated?
Authors: Johnston David A.
Published: October 2006

Earlier estimates of the chlorine emission from volcanoes, based upon evaluations of the preeruption magmatic chlorine content, are too low for some explosive volcanoes by a factor of 20 to 40 or more. Degassing of ash erupted during 1976 by Augustine Volcano in Alaska released 525 × 10
6
kilograms of chlorine (± 40 percent), of which 82 × 10
6
to 175 × 10
6
kilograms may have been ejected into the stratosphere as hydrogen chloride. This stratospheric contribution is equivalent to 17 to 36 percent of the 1975 world industrial production of chlorine in fluorocarbons.
Thermoregulatory Significance of Thoracic Lobes in the Evolution of Insect Wings
Authors: Douglas Matthew M.
Published: October 2006

The evolution of broadly attached thoracic lobes could have increased the body temperature excess of ancient wingless insects by 55 percent over that of lobeless forms. The subsequent expansion of these thoracic lobes for behavioral thermoregulation could have provided the morphological stage required for the evolution of functional wings.
Discovery of Natural Gain Amplification in the 10-Micrometer Carbon Dioxide Laser Bands on Mars: A Natural Laser
Authors: Mumma Michael J. , Buhl David , Chin Gordon , Deming Drake , Espenak Fred , Kostiuk Theodor , Zipoy David
Published: October 2006

Fully resolved intensity profiles of various lines in the carbon dioxide band at 10.4 micrometers have been measured on Mars with an infrared heterodyne spectrometer. Analysis of the line shapes shows that the Mars atmosphere exhibits positive gain in these lines. The detection of natural optical gain amplification enables identification of these lines as a definite natural laser.
Iron Ore: From Depletion to Abundance
Authors: Kakela Peter J.
Published: October 2006

Following World War II, Americans feared their iron ore supplies were depleted. The steel industry attempted to increase supplies by exploring foreign countries for new, high-grade hematite ores and experimenting with technology that upgraded low-grade domestic taconite ores into acceptable, but apparently uneconomical, pellets. Government did little at first, but the Korean War renewed fears of domestic resource exhaustion. Congress quickly enacted loan guarantees, rapid tax write-offs, and other tax policies that helped commercialize taconite pellets for national defense. These policies lingered long after the Korean War ended. Other policies bolstering taconite were enacted on the state level well after taconite had replaced hematite as industry's ore of choice. Understanding how government policies helped to develop pelletized lean iron ore may help in thinking about current policy suggestions aimed at easing our energy crisis or other mineral shortages. For taconite, too much government help came too late.
New Academic Positions: The Outlook in Europe and North America
Authors: Kidd Charles V.
Published: October 2006

During the 1960's, Canada, France, Germany, the United Kingdom, and the United States all experienced periods of rapid growth of research expenditures and of university enrollments followed by declines in growth rates. This sequence has generated the current severe shortages of new academic positions, with a resulting long-range threat to the vitality of academic science. Declines in the 18-year-old cohort in the United States, and especially in Canada, aggravate the problem. The United States is the only one of these countries that has not adopted a modest program to deal with the problems by creating fellowships or new positions.
Ocean Research Under Foreign Jurisdiction
Authors: Wooster Warren S.
Published: October 2006

In more than one-fourth of recent cases, U.S. marine scientists desiring to work off the shores of other countries were denied access or encountered inordinate delays in approval of their requests. The regime for marine scientific research proposed in the draft text of the Convention on the Law of the Sea may alleviate some difficulties but will not change the predominant influence of political considerations on decisions affecting clearance for research.
Physical Effects of Vehicular Disturbances on Arid Landscapes
Authors: Iverson Richard M. , Hinckley Bern S. , Webb Robert M. , Hallet Bernard
Published: October 2006

Field experiments indicate that the use of off-road vehicles on arid land increases the amount and frequency of water runoff and erosion by decreasing soil porosity, infiltration capacity, effectiveness of surface stabilizers, and hydraulic resistance to overland flow. These effects are long-lived and may result even when the use of these vehicles is slight.
Precambrian Perspectives
Authors: Goodwin Alan M.
Published: October 2006

The Precambrian record is interpreted in terms of an evolutionary progression that moves in the direction of increasing continental stability. An early, highly mobile microplate tectonics phase progressed through a more stable, largely intracratonic, ensialic, mobile belt phase to the modern macroplate tectonics phase that involves large, rigid lithospheric plates. Various phases are characterized by distinctive crustal associations. Three controls—bulk earth heat production, crustal fractionation and cratonization, and atmospheric oxygen accumulation—are viewed as the cumulative cause of the trends and events that characterize the crust at different stages of development, from its inception approximately 4.6 billion years ago to the present.
Possible Adaptive Value of Water Exchanges in Flexible-Shelled Eggs of Turtles
Authors: Packard GARY C. , Packard Mary J. , Boardman Thomas J. , Ashen M. Dominique
Published: October 2006

Use of energy reserves by embryos of common snapping turtles (
Chelydra serpentina
) is related to the hydric conditions to which eggs are exposed during incubation and to the net exchanges of water through the eggshells. Embryos developing inside eggs with a relatively favorable water balance use more of their energy reserves metabolically and grow larger before hatching than embryos inside eggs with less favorable water exchanges.
Female Feathering in Sebright Cocks Is Due to Conversion of Testosterone to Estradiol in Skin
Authors: George Fredrick W. , Noble Janet F. , Wilson Jean D.
Published: October 2006

Sebright cocks develop a female feathering pattern but revert to normal male feathering after castration. Administration of testosterone to castrated cocks causes male comb development and reappearance of female feathering. Dihydrotestosterone treatment supports development of a male comb but does not induce female feathering. Since testosterone but not dihydrotestosterone is converted to estradiol in the skin of the Sebright, the female feathering appears to be the result of increased conversion of testosterone to estradiol.
Quiet Zone Within a Seismic Gap near Western Nicaragua: Possible Location of a Future Large Earthquake
Authors: Harlow David H. , White Randall A. , Cifuentes Ines Lucia , Aburto Q. Arturo
Published: October 2006

A 5700-square-kilometer quiet zone occurs in the midst of the locations of more than 4000 earthquakes off the Pacific coast of Nicaragua. The region is indicated by the seismic gap technique to be a likely location for an earthquake of magnitude larger than 7. The quiet zone has existed since at least 1950; the last large earthquake originating from this area occurred in 1898 and was of magnitude 7.5. A rough estimate indicates that the magnitude of an earthquake rupturing the entire quiet zone could be as large as that of the 1898 event. It is not yet possible to forecast a time frame for the occurrence of such an earthquake in the quiet zone.
Spectral Analysis of Tropospheric Aerosol Measurements Obtained with a New Fast Response Sensor
Authors: Tropp R. J. , Brock J. R. , Kuhn P. J.
Published: October 2006

A new fast response sensor was used in aircraft studies of fluctuations in the size distributions of tropospheric aerosol and their relation to fluctuations of trace gas concentrations and light scattering coefficients. Spectral analysis of data upwind of Buffalo, New York, and Houston, Texas, suggests important roles for atmospheric turbulence and chemical reaction in aerosol fluctuations.
Recruitment in a Sea Anemone Population: Juvenile Substrate Becomes Adult Prey
Authors: Sebens Kenneth P.
Published: October 2006

Populations of the sea anemone
Anthopleura xanthogrammica
(Brandt) occur in tide pools and surge channels below intertidal mussel beds where they capture mussels dislodged by wave action and by sea star foraging. Dense concentrations of small juvenile anemones occur only within mussel beds and are probably the result of larval settlement or differential survival in that habitat. Areas experimentally cleared of anemones showed that recruitment was primarily by migrating juveniles and that the rate of immigration over a 2-year period was much higher in experimental removal areas near mussel beds than in those further away. Mussel beds thus function as an important juvenile habitat (refuge and nursery); juveniles later migrate downward and are then in a position to capture dislodged mussels and grow to adult size.
Phytochemical Deterrence of Snowshoe Hare Browsing by Adventitious Shoots of Four Alaskan Trees
Authors: Bryant John P.
Published: October 2006

After snowshoe hares have severely browsed deciduous trees and shrubs, these woody plants produce adventitious shoots that are extremely unpalatable to them. The adventitious shoots of four common boreal forest trees contain significantly higher concentrations of terpene and phenolic resins than the mature-growth-form twigs of the same species. These resins are experimentally shown to be repellent to snowshoe hares and appear to explain the avoidance of adventitious shoots by hares. The production of adventitious shoots after intense hare browsing and the avoidance of these shoots by hares may play an important role in the 10-year hare cycle.
Selective Herbivory in Tassel-Eared Squirrels: Role of Monoterpenes in Ponderosa Pines Chosen as Feeding Trees
Authors: Farentinos R. C. , Capretta P. J. , Kepner R. E. , Littlefield V. M.
Published: October 2006

Ponderosa pine twigs collected from trees used by tassel-eared squirrels as sources of cortical tissue for food contained smaller amounts of monoterpenes than twigs from similar trees not used by the squirrels as food sources. Of the 18 monoterpenes isolated from the twig samples, α-pinene was the best single predictor of food source trees. In experiments with captive tassel-eared squirrels, consumption of a preferred food was inversely correlated with the concentration of α-pinene added to the food.
Squalene in Petroleum Asphaltenes
Authors: Samman N. , Ignasiak T. , Chen C.-J. , Strausz O. P. , Montgomery D. S.
Published: October 2006

Squalene, 2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene, a new biological marker, has been detected in various petroleum asphaltenes and their pyrolysis products. Since squalene is the most common triterpenoid in nature and the biological precursor of the important tetra- and pentacyclic triterpane markers, its detection in asphaltene suggests new ways for marker correlations.
Mutator Activity in Maize: Timing of Its Activation in Ontogeny
Authors: Robertson Donald S.
Published: October 2006

Mutator activity in maize seems not to be active throughout the development of the plant, but to arise late in ontogeny, and to be developmentally rather than chronologically triggered.
Spectroscopic Detection of Stratospheric Hydrogen Cyanide
Authors: Coffey M. T. , Mankin W. G. , Cicerone R. J.
Published: October 2006

A number of features have been identified as absorption lines of hydrogen cyanide in infrared spectra of stratospheric absorption obtained from a high-altitude aircraft. Column amounts of stratospheric hydrogen cyanide have been derived from spectra recorded on eight flights. The average vertical column amount above 12 kilometers is 7.1 ± 0.8 × 10
14
molecules per square centimeter, corresponding to an average mixing ratio of 170 parts per trillion by volume.
Metals in Estuarine Sediments: Factor Analysis and Its Environmental Significance
Authors: Bopp Frederick , Biggs Robert B.
Published: October 2006

Q
-mode factor analysis has been used to partition the variability of environmentally active metals in Delaware Bay sediments. Three factors, identified as a natural background source, an oceanic or seawater source, and an estuarine source, account for 96 percent of the metal variability.
Measurements of the Stratospheric Plume from the Mount St. Helens Eruption: Radioactivity and Chemical Composition
Authors: Leifer R. , Hinchliffe L. , Fisenne I. , Franklin H. , Knutson E. , Olden M. , Sedlacek W. , Mroz E. , Cahill T.
Published: October 2006

Gas measurements made in the stratospheric plume from the eruption of Mount St. Helens on 18 May 1980 were not consistent with a reported large injection of radon-222 into the atmosphere. No enrichment in the volatile element polonium was found in filter samples, and the ratio of polonium-210 to lead-210 was not different from background values. Data obtained with an experimental impactor, flown shortly after the eruption, showed an increase of 10
3
in the stratospheric number concentration of submicrometer sulfate particles compared to concentrations before the eruption.
An Unusual Form of Lipid Linkage to the CD45 Peptide
Authors: Takeda Akiko , Maizel Abby L.
Published: October 2006

Some protein kinases and phosphatases are myristoylated on their amino terminus, which perhaps contributes to subcellular localization or regulation. Glycoprotein CD45, a hematopoietic tyrosine phosphatase, was examined for fatty acid content. The CD45 protein incorporated [
3
H]myristate, but little [
3
H]palmitate. The label was not metabolized and reincorporated into amino acids or saccharides, as revealed by peptide maps of CD45 labeled with [
3
H]myristate,
14
C-labeled amino acids, [
35
S]methionine, or
125
I, and glycosidase treatments, respectively. The myristate label was resistant to mild alkaline methanolysis and was found in fatty acid and sphingosine, indicating an unusual form of lipid attachment to CD45.
High-Resolution X-ray Observations of the Orion Nebula
Authors: Ku W. H.-M. , Righini-Cohen G. , Simon M.
Published: October 2006

Observations of the Trapezium region in the Orion Nebula obtained with the high-resolution x-ray imaging instrument on board the Einstein Observatory reveal at least 58 sources of x-ray emission. All but two of the sources can be identified with visible stars. The strongest x-ray source is the star θ
1
C, which excites the emission nebula. Its x-ray luminosity is 6 × 10
32
ergs per second. The rest of the x-ray sources may be identified with stars of all spectral types. Strong x-ray emission is not observed from members of the infrared cluster embedded within the Orion molecular cloud.
Biological Control in Agroecosystems
Authors: Batra Suzanne W. T.
Published: October 2006

Living organisms are used as biological pest control agents in (i) classical biological control, primarily for permanent control of introduced perennial weed pests or introduced pests of perennial crops; (ii) augmentative biological control, for temporary control of native or introduced pests of annual crops grown in monoculture; and (iii) conservative or natural control, in which the agroecosystem is managed to maximize the effect of native or introduced biological control agents. The effectiveness of biological control can be improved if it is based on adequate ecological information and theory, and if it is integrated with other pest management practices.
Maya Archeology
Authors: Willey Gordon R.
Published: October 2006

Maya beginnings go back at least 4000 years in southern Mexico and Central America. The Maya of the tropical lowlands were one of several linguistically distinct groups who occupied pre-Columbian Mesoamerica. Their complex social order and civilization, which arose from early village farming, encompassed remarkable achievements in architecture, the arts, and hieroglyphic writing. Their Classic civilization (A.D. 250 to 1000) was a tightly integrated system in which subsistence, technology, settlement, the arts, and ideology closely intermeshed. Their decline and the subsequent Postclassic Period (A.D. 1000 to .1520), the continuing subjects of debate among Mayanists, are perhaps best understood in the light of more widespread Mesoamerican trends and changes.
Internal Hydrogen Bond Formation in a
syn
-Hydroxyepoxide
Authors: Glusker Jenny P. , Zacharias David E. , Whalen Dale L. , Friedman Steve , Pohl Teresa M.
Published: October 2006

The existence of an internal hydrogen bond in a compound representative of a
syn
diol epoxide (a possible intermediate in chemical carcinogenesis by certain polycyclic aromatic hydrocarbons) has been demonstrated by x-ray crystallographic and nuclear magnetic resonance studies. This internal hydrogen bond was found in 3,4-epoxy-2-methyl-1,2,3,4-tetrahydro-1-naphthol and was shown to persist in dioxane-water solutions containing up to 80 mole percent water. In this structure, the 1-hydroxy and 2-methyl groups are shown to occupy axial positions. In the anti diol epoxide, which has no internal hydrogen bond, analogous groups are equatorial. Crystals of the compound were unstable in the x-ray beam while the data were being collected (even at low temperatures), presumably as a result of decomposition.
Computers: A Survey of Trends and Limitations
Authors: Birnbaum Joel S.
Published: October 2006

Enormous progress in electronic technology is accelerating the use of computers in everyday life. In this article trends in hardware, input-output technology, computer architecture, software, communications, and artificial intelligence are examined and complexity is identified as a limitation to further progress. Promising directions of research, which may extend the range of computer applications, are discussed.
Computers in Scientific Instrumentation
Authors: Enke C. G.
Published: October 2006

The rapid evolution of computer applications in scientific instrumentation is briefly traced from early data processing to modern computer-based instruments. Computer and interface developments have both contributed to this evolution. The form of the computer used strongly affects the ease of instrument operation and the degree of functional adaptability. Probable pathways toward instruments with increased "intelligence" include the development and intelligent control of powerful "multidimensional" instruments, the implementation of hierarchical computer networks and multiprocessor controllers, and the simplification of programming. The importance of the scientist's involvement in these developments is discussed.
Ultrafast Phenomena in Semiconductor Devices
Authors: Shank C. V. , Auston D. H.
Published: October 2006

Evolving high-speed semiconductor technology requires a more complete understanding of semiconductors on a picosecond time scale. This article discusses ultrafast phenomena that may influence device performance and describes new experimental methods utilizing short optical pulses to investigate materials and device structures.
Advances in Process Control
Authors: Morrison David L. , Snow Richard H. , Lamoureux John P.
Published: October 2006

Advances in electronics and computers have enabled industries to attain better control of their processes with resulting increases in quality, productivity, profitability, and compliance with government regulations. With a hierarchy of computers, distributed data acquisition, and information processing and control, it is possible to achieve overall optimum performance of a plant. While further advances in microprocessors and large-scale integration will be useful to the process engineer, major improvements in process control await advances in sensor technology and software.
Japan—U.S. Competition: Semiconductors Are the Key
Authors: Walsh John
Published: October 2006

Japan appears to have achieved a breakthrough with its success in selling the 16K random access memory chip. The rivalry between Japan and the United States over integrated circuits could make the 1980's crucial years in the contest for the lead in the world electronics trade.
Computers and Electronics for Individual Services
Authors: Davis Ruth M.
Published: October 2006

Personal computers priced for the consumer market have a wide range of applications and variable memory, computational, and display capabilities. The genesis of individual computing devices, some of their applications, and the market for personal computers are discussed in this article.
Kinetics of Delignification: A Molecular Approach
Authors: Yan Johnson F.
Published: October 2006

A treelike model has been proposed for the structure of lignin. Kinetics of delignification are formulated to account for the cleavage of linkages along the linear primary chains and at the cross-links. Experimental data obtained from isothermal delignification are used to verify this theory. Good agreement has been obtained in calculating the delignification curves. Activation energies are found to be 172 kilojoules per mole of cross-links and 132 kilojoules per mole of aryl ether bonds.
Search for Interstellar Superheavy Hydrogen
Authors: Jura M. , York D. G.
Published: October 2006

Models for fundamental physical interactions allow for the existence of stable or nearly stable elementary particles much heavier than the proton. Stellar spectra were searched for a positively charged superheavy particle, X
+
, which, with a bound electron, should appear as apparently superheavy neutral hydrogen in the interstellar medium. An upper limit for the abundance of X relative to normal hydrogen in the line of sight toward the bright star γ Cassiopeiae is 2 "×" (multiplication sign) with "×" 10
–8
.
Plant Phenols Utilized as Nutrients by a Phytophagous Insect
Authors: Bernays E. A. , Woodhead S.
Published: October 2006

Phenols are commonly regarded as feeding deterrents for phytophagous insects, but the tree locust
Anacridium melanorhodon
survives better and grows faster when certain phenols are added to a food plant that is relatively low in both protein and phenols. The phenols are at high concentration in the common host plants. Much of the phenol retained by the insect becomes bound in the cuticle where it probably stabilizes the protein.
Comet Encke: Radar Detection of Nucleus
Authors: Kamoun P. G. , Campbell D. B. , Ostro S. J. , Pettengill G. H. , Shapiro I. I.
Published: October 2006

The nucleus of the periodic comet Encke was detected in November 1980 with the Arecibo Observatory's radar system (wavelength, 12.6 centimeters). The echoes in the one sense of circular polarization received imply a radar cross section of 1.1 ± 0.7 square kilometers. The estimated bandwidth of these echoes combined with an estimate of the rotation vector of Encke yields a radius for the nucleus of 1.5
+2.3
–1.0
kilometers. The uncertainties given are dependent primarily on the range of models considered for the comet and for the manner in which its nucleus backscatters radio waves. Should this range prove inadequate, the true value of the radius of the nucleus might lie outside the limits given.
Carter's Plan for MX Lives On
Authors: Smith R. Jeffrey
Published: October 2006

Early this year, the U.S. land-based force of nuclear missiles became vulnerable—on paper—to destruction in a preemptive attack by the Soviet Union. The Air Force has worried about this problem for a long time, searching high and low for a better place to put both the existing, silo-based Minuteman missiles and a new missile, the MX.

Under the Carter Administration, the Air Force agreed to a missile basing plan known as MPS, for multiple protective shelters. The Reagan Administration has ostensibly dropped this plan in favor of several alternatives.

Previous articles in this series explored why U.S. officials became alarmed about missile vulnerability; the genesis of a short-term plan to put more missiles into silos; continuing Air Force opposition to a plan for missiles on constantly roving aircraft; and a bizarre plan to bury missiles deep underground.
Solar Flares, Proton Showers, and the Space Shuttle
Authors: Rust David M.
Published: October 2006

The space shuttle era will focus renewed attention on the hazards of the space environment to human habitation. The chief unpredictable hazard for astronauts is energetic proton radiation from solar flares. In some orbits, there is no reasonable level of shielding material that will protect shuttle occupants from potentially lethal doses of radiation. The effects of a solar flare that occurred during the first flight of the Columbia are discussed and current flare research reviewed. The emphasis is on progress made during the recent international Solar Maximum Year toward understanding the origins of proton showers.
Stratospheric Nitrogen Dioxide in the Vicinity of Soufriere, St. Vincent
Authors: Romick G. J. , Murcray D. G. , Williams W. J.
Published: October 2006

In April 1979, measurements of nitrogen dioxide in the upper atmosphere were made near Soufriere Volcano by twilight optical-absorption techniques. The derived value of 5 × 10
15
molecules per square centimeter column implies an enhancement of 25 percent over earlier abundances measured in the same latitudinal regions. This enhancement may represent the normal stratospheric variability of nitrogen dioxide in the equatorial region but in any case may be considered an upper limit to the volcano's effect on the total nitrogen dioxide abundance.
Microwave Edge Diffraction by Features in Saturn's Rings: Observations with Voyager 1
Authors: Marouf Essam A. , Tyler G. Leonard
Published: October 2006

Classical edge diffraction patterns are formed at centimeter wavelengths by several features of Saturn's rings. These patterns were discovered in 3.6- and 13-centimeter radio signals from Voyager 1 during occultation by the rings. The observed shapes are in agreement with theoretical patterns computed for screens of perfectly abrupt edges having large but finite opacity. Comparison with models in which the opacity at the edge tapers to zero from a finite value sets a new bound of less than about 200 meters on the microwave edge thickness. Certain features of the data suggest a smaller upper bound of about 130 meters on the edge thickness.
Frontiers in Crop Production: Chemical Research Objectives
Authors: Geissbuhler Hans , Brenneisen Paul , Fischer Hans-Peter
Published: October 2006

The science of chemistry and chemicals will continue to be an integral part of future crop production technologies. In assessing and defining the future role of chemistry three imperatives must be considered: (i) the necessity to preserve natural resources, (ii) the complementary solutions offered by the rapidly advancing biological sciences, and (iii) the specific requirements of developing regions where increasing crop productivity is most important. Chemical research objectives for improving crop protection and crop growth must take into account the perceivable and potential changes in crop production techniques, which, in turn, are dictated by a number of accentuating constraints.
Studies of Relativistic Uranium Nuclei with Dielectric Track Detectors
Authors: Ahlen S. P. , Tarlé G. , Price P. B.
Published: October 2006

The cross section for the breakup of relativistic uranium projectiles (energy ∼ 35 billion electron volts) into two large fragments in the track detector CR-39 was measured and found to be about half of the geometric cross section. The range of the uranium projectiles was also measured and found to agree with that predicted by the Bethe theory when modified to account for the capture of orbital electrons by the projectiles.
Cloud Feedback: A Stabilizing Effect for the Early Earth?
Authors: Rossow William B. , Henderson-Sellers Ann , Weinreich Stephen K.
Published: October 2006

The effect of variations in cloud cover, optical properties, and fractional distribution with altitude on the mean surface temperature of a model of the early earth has been investigated. In all cases examined, cloud-climate feedbacks result in temperatures greater than those in models with no cloud feedbacks. If the model of hydrospheric feedback effects is correct, then cloud feedbacks are as important to the climate as changes in solar luminosity and atmospheric composition during the earth's atmospheric evolution. In particular, the early earth need not become completely ice-covered if strong negative cloud feedbacks occur. However, until a proper understanding of cloud feedbacks is available, conclusions regarding conditions in the early atmosphere must remain in doubt.
Orthopyroxene Exsolution in Augite: A Two-Step, Diffusion-Transformation Process
Authors: Isaacs Andrew M. , Peacor Donald R.
Published: October 2006

Orthopyroxene lamellae exsolved from augite on (100) are shown to grow by a two-step process involving (i) the diffusion of calcium and (magnesium, iron) to form clinohypersthene and (ii) the inversion of clinohypersthene to orthopyroxene, probably by glide twinning. If complete inversion is prevented by cooling or steep concentration gradients, the two-step process produces orthopyroxene with narrow margins of clinohypersthene. Measured elemental concentration gradients at (100) lamellar interfaces support this mechanism.
Synergistic Action of Potassium Chloride and Magnesium Sulfate on Parasitoid Wasp Oviposition
Authors: Nettles William C. , Morrison Richard K. , Xie Zhong-Neng , Ball Debra , Shenkir Cyndy A. , Vinson S. Bradleigh
Published: October 2006

A dilute solution of potassium chloride and magnesium sulfate induces oviposition in artificial eggs by the egg parasitoids
Trichogramma pretiosum
and
T. minutum
. The ability to obtain large numbers of eggs through the use of this inexpensive solution is a major advance toward the development of diets and the large-scale production of
Trichogramma
spp. in vitro.
Use of the Space Shuttle for Remote Sensing Research: Recent Results and Future Prospects
Authors: Settle Mark , Taranik James V.
Published: October 2006

Routine access to low earth orbit provided by the space shuttle holds great potential for global studies of the earth's resources and its environment. A successful test flight of the Columbia orbiter in November 1981 demonstrated the utility and versatility of the shuttle for earth-related research. A series of remote sensing experiments is currently planned for the mid-1980's that will more fully exploit the shuttle's earth observation capabilities.
Eruption of El Chichón Volcano, Chiapas, Mexico, 28 March to 7 April 1982
Authors: Hoffer Jerry M. , Gomez P. Filiberto , Muela Pedro
Published: October 2006

El Chichón volcano erupted at 2322 hours on 28 March 1982 after being dormant during historic times. Three major eruptions of tephra occurred between that date and 7 April, discharging approximately 0.3 cubic kilometer of andesitic pyroclastic material. The initial eruption produced crystal-rich tephra of higher silica and alkali content than the lithic pyroclastic materials of the second and third eruptions. The initial tephra consists of primarily juvenile materials, whereas the later eruptions produced both lithic and juvenile fractions.
Catalysis by Transition Metals: Metal-Carbon Double and Triple Bonds
Authors: Schrock Richard R.
Published: October 2006

Several well-characterized transition metal catalysts contain a metal-carbon double bond or a metal-carbon triple bond. In other homogeneous (or heterogeneous) catalyst systems in which the metal is likely to be in a relatively high oxidation state, such as molybdenum(VI) or tungsten(VI), metal-carbon multiple bonds may play an important role. Some recent results suggest that even supposedly well understood reactions such as ethylene polymerization may actually involve catalysts that behave as if they contained a metal-carbon double bond instead of a metal-carbon single bond. The chemistry of metal-carbon double and triple bonds should eventually complement and perhaps overlap the known chemistry of complexes containing metal-oxygen double bonds or metal-nitrogen triple bonds, respectively; unique catalytic reactions involving carbon, nitrogen, and oxygen ligands multiply bonded to transition metals are therefore possible.
The University's Entry Fee to Federal Research Programs
Authors: Arnow Kathryn Smul
Published: October 2006

The university pays for its benefits from a federally financed project with its own investments in the faculty scientist and not, as is often assumed, by its absorption of project costs that are not reimbursed by the government. An analysis of the exchange of resources between the university, the scientist, the discipline, and the government shows, however, that by absorbing costs the institution gains acceptance as a host for federal research. Funds for this ticket of admission are drawn away from several groups on the campus. In exploring whether there should be such an entry fee, the pragmatic response of the National Commission on Research is considered.
Neutron-Induced Fission of Uranium: A Dating Method for Lunar Surface Material
Authors: Eugster O. , Eberhardt P. , Geiss J. , Grögler N.
Published: October 2006

Volcanic glasses collected on the rim of Shorty Crater in the Apollo 17 area were formed 3.63 × 10
9
years ago. The amounts of xenon-136 produced by neutron-induced fission of uranium-235 indicate that the glasses resided on the lunar surface for about 38 million years before they were deeply buried. The glass spherules were reexcavated by the impact that formed Shorty Crater 17 million years ago, and remained undisturbed until they were collected.
The Autonomous Viking
Authors: Hutchings Edward
Published: October 2006

The two Viking spacecraft launched to Mars in 1975 were designed for 90 days of intense observations followed by an extended mission phase to end in 1978. Because the spacecraft were still operating so well in 1978, three more mission phases were added and the project was not officially terminated until 1980. During these last three mission phases delays in controlling the orbiters from the earth increased. The spacecraft were kept functional and the length of the Viking mission was extended because the ground crew, over a period of 2 years, gradually made the orbiters autonomous.
Understanding Nonrenewable Resource Supply Behavior
Authors: Bohi Douglas R. , Toman Michael A.
Published: October 2006

Decisions concerned with finding, developing, and extracting nonrenewable resources are dynamically interrelated in complex ways. Economic theory provides a description of this process that yields useful insights, but there are gaps between theory and empirical applications that hinder our understanding of how supply responds to changes in economic incentives. Consequently, many questions concerning market efficiency as opposed to government intervention remain open.
The Electric Power Research Institute
Authors: Starr Chauncey
Published: October 2006

The Electric Power Research Institute, now 10 years old, was formed by the electric utility industry in response to the threat of federal legislation to create a government agency, funded by a 1 percent tax on utility gross revenue, to undertake research and development. Legislation was proposed in the early 1970's by the Senate Commerce Committee as a result of the massive 1965 Northeast blackout and subsequent public criticism. In March 1972, the Senate was persuaded to give the electric utility industry 1 year to establish an industry-managed and supported substitute to the proposal. This article describes the subsequent history and the program today.
Syneresis of Vitreous by Carbon Dioxide Laser Radiation
Authors: Bridges T. J. , Patel C. K. N. , Strnad A. R. , Wood O. R. , Brewer E. S. , Karlin D. B.
Published: October 2006

In carbon dioxide laser surgery of the vitreous a process of vaporization has been advocated. In this report syneresis, a thermal liquefaction of gel, is shown to be over ten times more efficient on an energy basis than vaporization. Syneresis of vitreous is experimentally shown to be a first-order kinetic process with an activation energy of 41 ± 0.5 kilocalories per mole. A theory of laser surgery in which this figure is used agrees closely with results from laser experiments on human eye-bank vitreous. The syneresis of vitreous by carbon dioxide laser radiation could lead to a more delicate form of ocular microsurgery, and application to other biological systems may be possible.