bluuebunny/crossref_metadata_2025 huggingface dataset:
Cogeneration of Electric Energy and Nitric Oxide
Authors: Vayenas C. G. , Farr R. D.
Published: October 2006

A solid electrolyte fuel cell operating on ammonia fuel has been constructed and tested. The yield of nitric oxide can exceed 60 percent with simultaneous electric energy production. Two dimensionless numbers have been identified which govern the product selectivity and power output of this fuel cell. The cell appears to be a promising candidate for nitric acid and electric energy cogeneration.
High-Strength, Low-Alloy Steels
Authors: Rashid M. S.
Published: October 2006

High-strength, low-alloy (HSLA) steels have nearly the same composition as plain carbon steels. However, they are up to twice as strong and their greater load-bearing capacity allows engineering use in lighter sections. Their high strength is derived from a combination of grain refinement; precipitation strengthening due to minor additions of vanadium, niobium, or titanium; and modifications of manufacturing processes, such as controlled rolling and controlled cooling of otherwise essentially plain carbon steel. HSLA steels are less formable than lower strength steels, but dualphase steels, which evolved from HSLA steels, have ferrite-martensite microstructures and better formability than HSLA steels of similar strength. This improved formability has substantially increased the utilization potential of high-strength steels in the manufacture of complex components. This article reviews the development of HSLA and dual-phase steels and discusses the effects of variations in microstructure and chemistry on their mechanical properties.
Sintered Superhard Materials
Authors: Wentorf R. H. , DeVries R. C. , Bundy F. P.
Published: October 2006

Diamond or cubic boron nitride particles can be sintered into strong masses at high temperatures and very high pressures at which these crystalline forms are stable. Most of the desirable physical properties of the sintered masses, such as hardness and thermal conductivity, approach those of large single crystals; their resistance to wear and catastrophic splitting is superior. The sintered masses are produced on a commercial scale and are increasingly used as cutting tools on hard or abrasive materials, as wire-drawing dies, in rock drills, and in special high-pressure apparatus.
Toxic Gases from Fires
Authors: Terrill James B. , Montgomery Ruth R. , Reinhardt Charles F.
Published: October 2006

The major lethal factors in uncontrolled fires are toxic gases, heat, and oxygen deficiency. The predominant toxic gas is carbon monoxide, which is readily generated from the combustion of wood and other cellulosic materials. Increasing use of a variety of synthetic polymers has stimulated interest in screening tests to evaluate the toxicity of polymeric materials when thermally decomposed. As yet, this country lacks a standardized fire toxicity test protocol.
Measuring the Societal Benefits of Innovation
Authors: Tewksbury J. G. , Crandall M. S. , Crane W. E.
Published: October 2006

Quantitative economic analysis of 20 commercial innovations shows that there is great benefit to society that is often not reflected in the rate of return to the innovator. The study also documents the importance of marketing strategy and proper consideration of risk.
Spaceborne Imaging Radar: Geologic and Oceanographic Applications
Authors: Elachi Charles
Published: October 2006

Synoptic, large-area radar images of the earth's land and ocean surface, obtained from the Seasat orbiting spacecraft, show the potential for geologic mapping and for monitoring of ocean surface patterns. Structural and topographic features such as lineaments, anticlines, folds and domes, drainage patterns, stratification, and roughness units can be mapped. Ocean surface waves, internal waves, current boundaries, and large-scale eddies have been observed in numerous images taken by the Seasat imaging radar. This article gives an illustrated overview of these applications.
Mount St. Helens Ash from the 18 May 1980 Eruption: Chemical, Physical, Mineralogical, and Biological Properties
Authors: Fruchter Jonathan S. , Robertson David E. , Evans John C. , Olsen Khris B. , Lepel Elwood A. , Laul Jagdish C. , Abel Keith H. , Sanders Ronald W. , Jackson Peter O. , Wogman Ned S. , Perkins Richard W. , Van Tuyl Harold H. , Beauchamp Raymond H. , Shade John W. , Daniel J. Leland , Erikson Robert L. , Sehmel George A. , Lee Richard N. , Robinson Alfred V. , Moss Owen R. , Briant James K. , Cannon William C.
Published: October 2006

Samples of ash from the 18 May 1980 eruption of Mount St. Helens were collected from several locations in eastern Washington and Montana. The ash was subjected to a variety of analyses to determine its chemical, physical, mineralogical, and biological characteristics. Chemically, the ash samples were of dacitic composition. Particle size data showed bimodal distributions and differed considerably with location. However, all samples contained comparable amounts of particles less than 3.5 micrometers in diameter (respirable fraction). Mineralogically, the samples ranged from almost totally glassy to almost totally crystalline. Crystalline samples were dominated by plagioclase feldspar (andesine) and orthopyroxene (hypersthene), with smaller amounts of titanomagnetite and hornblende. All but one of the samples contained from less than 1 percent to 3 percent free crystalline silica (quartz, trydimite, or cristobalite) in both the bulk samples and 1 to 2 percent in the fractions smaller than 3.5 micrometers. The long-lived natural radionuclide content of the ash was comparable to that of crustal material; however, relatively large concentrations of short-lived radon daughters were present and polonium-210 content was inversely correlated with particle size. In vitro biological tests showed the ash to be nontoxic to alveolar macrophages, which are an important part of the lungs' natural clearance mechanism. On the basis of a substantial body of data that has shown a correlation between macrophage cytotoxicity and fibrogenicity of minerals, the ash is not predicted to be highly fibrogenic.
Late Wisconsin Climate of Northern Florida and the Origin of Species-Rich Deciduous Forest
Authors: Watts W. A. , Stuiver M.
Published: October 2006

Species-rich mesic forest covered northern Florida as early as 14,000 radiocarbon years before present. It probably originated in deciduous tree populations already present locally in conifer forest between 24,000 and 18,600 years before present. The cold, dry Late Wisconsin climate ended before 14,600 years before present. A transitional warm, dry phase preceded a precipitation increase at 14,000 years before present.
Science and the University
Authors: Giamatti A. Bartlett
Published: October 2006

The federal government-university relationship in scientific research has been eroded by excessive, unthinking regulations for the purposes of accountability. The Office of Management and Budget's Circular A-21 continues to jeopardize the quality of government-sponsored research in universities by demanding wasteful, meaningless work-load documentation. These regulatory demands must be revised to reflect the realistic obligations of accountability by a leadership capable of transcending special interests. Mutual respect between government and universities must be restored to achieve a partnership that helps better the national life while also protecting the integrity of the scientific faculty and its mission.
Curvilinear Motion in the Absence of External Forces: Naïve Beliefs About the Motion of Objects
Authors: McCloskey Michael , Caramazza Alfonso , Green Bert
Published: October 2006

University students were asked to draw the path a moving object would follow in several different situations. Over half of the students, including many who had taken physics courses, evidenced striking misconceptions about the motion of objects. In particular, many students believed that even in the absence of external forces, objects would move in curved paths.
Origin of Lead in Andean Calc-Alkaline Lavas, Southern Peru
Authors: Tilton George R. , Barreiro Barbara A.
Published: October 2006

Lead isotope data from Quaternary andesitic lavas of the Arequipa and Barroso groups of southern Peru and from regional Precambrian granulitic gneisses reveal a lead component in the lavas from the gneisses. The lava leads can be accounted for by two-component mixtures of lead from mantle and lower crustal sources, although the mixing process need not have occurred in the lower crust.
"Atmospheric" Epoxidation of Benzo[
a
]pyrene by Ozone: Formation of the Metabolite Benzo[
a
]pyrene-4,5-Oxide
Authors: Pitts James N. , Lokensgard David M. , Ripley Paul S. , Van Cauwenberghe Karel A. , Van Vaeck Luk , Shaffer Steven D. , Thill Alan J. , Belser William L.
Published: October 2006

Benzo
[a]
pyrene deposited on a glass fiber filter reacts rapidly in the dark or light with ambient levels of ozone to yield a mixture of products that display strong direct mutagenicity in the Ames assay. The major stable contributor to this activity has been identified as benzo
[a]
pyrene-4,5-oxide, a DNA-binding metabolite in biological systems, known to be a strong direct mutagen with
Salmonella typhimurium
strain TA98.
Generation of New Mouse Sarcoma Viruses in Cell Culture
Authors: Rapp Ulf R. , Todaro George J.
Published: October 2006

Endogenous nontumor-producing type C viruses from C3H mice were used to generate rapid, solid tumor-inducing variants in cell culture. The new mouse sarcoma viruses induce undifferentiated sarcomas with a short latency period upon inoculation into newborn NIH Swiss mice. Transforming viruses appear only transiently, at a time when the virus-infected cells show morphologic alterations; both before and after this time, transforming viruses cannot be detected. These results show that variants of endogenous type C virus which contain transforming genes (oncogenes) can arise during spread of the endogenous virus in fibroblast lines in vitro as well as in susceptible tissues in vivo.
Grafts of Fetal Dopamine Neurons Survive and Improve Motor Function in Parkinson's Disease
Authors: Lindvall Olle , Brundin Patrik , Widner Håkan , Rehncrona Stig , Gustavii Björn , Frackowiak Richard , Leenders Klaus L. , Sawle Guy , Rothwell John C. , Marsden C. David , Björklund Marsden
Published: October 2006

Neural transplantation can restore striatal dopaminergic neurotransmission in animal models of Parkinson's disease. It has now been shown that mesencephalic dopamine neurons, obtained from human fetuses of 8 to 9 weeks gestational age, can survive in the human brain and produce marked and sustained symptomatic relief in a patient severely affected with idiopathic Parkinson's disease. The grafts, which were implanted unilaterally into the putamen by stereotactic surgery, restored dopamine synthesis and storage in the grafted area, as assessed by positron emission tomography with 6-L-[
18
F]fluorodopa. This neurochemical change was accompanied by a therapeutically significant reduction in the patient's severe rigidity and bradykinesia and a marked diminuation of the fluctuations in the patient's condition during optimum medication (the "on-off" phenomenon). The clinical improvement was most marked on the side contralateral to the transplant.
Synthesis Gas: A Raw Material for Industrial Chemicals
Authors: Pruett Roy L.
Published: October 2006

Rapid increases in the price of imported crude oil have accelerated a shift in the raw material base for chemical feedstocks from natural gas to crude oil to coal. Widespread use of ethylene as a feedstock has depended on the availability at attractive prices of natural gas and petroleum. As the resource base shifts from natural gas and petroleum to coal, ethylene is being replaced by synthesis gas (a mixture of hydrogen and carbon monoxide of varying composition), which can be manufactured directly from any of these carbonaceous sources. This trend is expected to accelerate in the 1980's. Organics likely to be produced from synthesis gas include ethanol, ethylene glycol, and vinyl acetate.
Impact on Agriculture of the Mount St. Helens Eruptions
Authors: Cook R. J. , Barron J. C. , Papendick R. I. , Williams G. J.
Published: October 2006

Ash from Mount St. Helens has fallen over a diverse agricultural area, with deposits of up to 30 kilograms per square meter. Crop losses in eastern Washington are estimated at about $100 million in 1980—about 7 percent of the normal crop value in the affected area and less than was expected initially. Production of wheat, potatoes, and apples will be normal or above normal because the favorable conditions for growth of these crops since the ashfall helped offset the losses. Alfalfa hay was severely lodged under the weight of the ash, but ash-contaminated hay is apparently nontoxic when eaten by livestock. The ash as an abrasive is lethal to certain insects, such as bees and grasshoppers, but populations are recovering. The ash has increased crop production costs by necessitating machinery repairs and increased tillage. On soil, the ash reduces water infiltration, increases surface albedo, and may continue to affect water runoff, erosion, evaporation, and soil temperature even when tilled into the soil. Ash on plant leaves reduced photosynthesis by up to 90 percent. Most plants have tended to shed the ash. With the possible exception of sulfur, the elements in the ash are either unavailable or present in very low concentrations; and no significant contribution to the nutrient status of soils is expected.
Azidoatrazine: Photoaffinity Label for the Site of Triazine Herbicide Action in Chloroplasts
Authors: Gardner Gary
Published: October 2006

Binding of the 4-azido analog of the herbicide atrazine to pea chloroplast membranes was compared with that of atrazine. When [
14
C]azidoatrazine was treated with 300-nanometer ultraviolet light in situ, reversibility of binding was lost in proportion to the duration of irradiation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of chloroplast membranes irradiated in the presence of [
14
C]-azidoatrazine indicated radioactivity in only one region, corresponding to a protein with a molecular weight of approximately 32,000. Azidoatrazine is a photoaffinity reagent for the triazine binding site in chloroplasts and serves as a label to identify this site, which may be the apoprotein of the secondary electron acceptor in photosystem II.
Brain Tumors in Owl Monkeys Inoculated with a Human Polyomavirus (JC Virus)
Authors: London William T. , Houff Sidney A. , Madden David L. , Fuccillo David A. , Gravell Maneth , Wallen William C. , Palmer Amos E. , Sever John L. , Padgett Billie L. , Walker Duard L. , ZuRhein Gabriele M. , Ohashi Takeo
Published: October 2006

Owl monkeys were inoculated intracerebrally, subcutaneously, and intravenously with JC, BK, or SV40 virus. Two of four adult owl monkeys inoculated with JC virus, a human polyomavirus, developed brain tumors at 16 and 25 months after inoculation, respectively. A grade 3 to grade 4 astrocytoma (resembling a human glioblastoma multiforme) was found in the left cerebral hemisphere and brainstem of one monkey. The second monkey developed a malignant tumor in the left cerebral hemisphere containing both glial and neuronal cell types. Impression smears prepared from unfixed tissue of this tumor showed cells that contained polyomavirus T antigen. Virion antigens were not detected. Tumor cells cultured in vitro also contained T antigen but were negative for virion antigen. Infectious virus was not isolated from extracts of this tumor.
Two G Protein Oncogenes in Human Endocrine Tumors
Authors: Lyons John , Landis Claudia A. , Harsh Griffith , Vallar Lucia , Grünewald Kurt , Feichtinger Hans , Duh Quan-Yang , Clark Orlo H. , Kawasaki Ernest , Bourne Henry R. , McCormick Frank
Published: October 2006

Somatic mutations in a subset of growth hormone (GH)-secreting pituitary tumors convert the gene for the α polypeptide chain (α
s
) of G
s
into a putative oncogene, termed
gsp
. These mutations, which activate α
s
by inhibiting its guanosine triphosphatase (GTPase) activity, are found in codons for either of two amino acids, each of which is completely conserved in all known G protein α chains. The likelihood that similar mutations would activate other G proteins prompted a survey of human tumors for mutations that replace either of these two amino acids in other G protein α chain genes. The first gene so far tested, which encodes the α chain of G
i2
, showed mutations that replaced arginine-179 with either cysteine or histidine in 3 of 11 tumors of the adrenal cortex and 3 of 10 endocrine tumors of the ovary. The mutant α
i2
gene is a putative oncogene, referred to as
gip2
. In addition,
gsp
mutations were found in 18 of 42 GH-secreting pituitary tumors and in an autonomously functioning thyroid adenoma. These findings suggest that human tumors may harbor oncogenic mutations in various G protein α chain genes.
Genetic Basis of Migratory Behavior in European Warblers
Authors: Berthold Peter , Querner Ulrich
Published: October 2006

The seasonal course and magnitude of migratory restlessness recorded in four populations of the blackcap
Sylvia atricapilla
differ in a population-specific fashion that is related to the distance of travel. Experimentally produced hybrids of an exclusively migratory European population and a partially migratory African population showed intermediate migratory restlessness and an intermediate percentage of birds displaying restlessness compared to the two parental stocks. These results demonstrate the genetic basis of migratory behavior in this avian species and support the hypothesis that partial migration of populations is due to polymorphism.
Magnetic Field Studies by Voyager 1: Preliminary Results at Saturn
Authors: Ness Norman F. , Acuña Mario H. , Lepping Ronald P. , Connerney John E. P. , Behannon Kenneth W. , Burlaga Leonard F. , Neubauer Fritz M.
Published: October 2006

Magnetic field studies by Voyager 1 have confirmed and refined certain general features of the Saturnian magnetosphere and planetary magnetic field established by Pioneer 11 in 1979. The main field of Saturn is well represented by a dipole of moment 0.21 ± 0.005 gauss-
R
S
3
(where 1 Saturn radius,
R
S
, is 60,330 kilometers), tilted 0.7° ± 0.35° from the rotation axis and located within 0.02
R
S
of the center of the planet. The radius of the magnetopause at the subsolar point was observed to be 23
R
S
on the average, rather than 17
R
S
. Voyager 1 discovered a magnetic tail of Saturn with a diameter of approximately 80
R
S
. This tail extends away from the Sun and is similar to type II comet tails and the terrestrial and Jovian magnetic tails. Data from the very close flyby at Titan (located within the Saturnian magnetosphere) at a local time of 1330, showed an absence of any substantial intrinsic satellite magnetic field. However, the results did indicate a very well developed, induced magnetosphere with a bipolar magnetic tail. The upper limit to any possible internal satellite magnetic moment is 5 × 10
21
gauss-cubic centimeter, equivalent to a 30-nanotesla equatorial surface field.
The Ginsberg Experiment: Modern and Prehistoric Evidence of a Bone-Flaking Technology
Authors: Stanford Dennis , Bonnichsen Robson , Morlan Richard E.
Published: October 2006

The discovery of butchered and modified bones of extinct Pleistocene fauna from Old Crow Flats, Yukon Territory, and the Dutton and Selby sites, Colorado, provides some of the earliest evidence for man in the New World. However, the significance of these discoveries rests entirely on the ability to determine whether these remains were modified by man. The results of experiments of elephant butchering, bone fracturing, and bone tool manufacturing support the hypothesis that these modified bones can be used to identify the presence of cultural activities.
Conflicting Objectives in Regulating the Automobile
Authors: Lave Lester B.
Published: October 2006

Federal regulation of automobile safety, emissions, and fuel economy is contradictory. Safety equipment and emissions control reduce fuel economy; reducing the size of automobiles is estimated to increase fatalities by 1400 a year and significantly increase serious injuries. These secondary impacts of regulation roughly double the estimated costs of achieving the individual goals. In formulating regulations, these contradictions must be taken into account, along with the effects on the price of the vehicle and its attractiveness to buyers.
Microwave Radiometric Measurements of Sea Surface Temperature from the Seasat Satellite: First Results
Authors: Hofer R. , Njoku E. G. , Waters J. W.
Published: October 2006

Initial results from the Seasat scanning multichannel microwave radiometer indicate that the sea surface temperature can be measured with a root-mean-square sensitivity of 1.2°C or better. The first microwave map of sea surface temperature for the entire Pacific has been produced.
The in vitro Classical Conditioning of the Gill Withdrawal Reflex of
Aplysia californica
Authors: Lukowiak Ken , Sahley Christie
Published: October 2006

Associative learning has been demonstrated in a reduced siphon, mantle, gill, and abdominal ganglion preparation of
Aplysia
. The preparations learned to respond to a previously neutral stimulus as a consequence of training in a classical conditioning paradigm. Backward conditioning, presentation of the conditioned stimulus alone, or presentation of the unconditioned stimulus at some random interval after presentation of the conditioned stimulus failed to produce conditioning. This model system can be used to study the neural mechanisms underlying associative learning.
Induction by Antigen of Intrathymic Apoptosis of CD4
+
CD8
+
TCR
lo
Thymocytes in Vivo
Authors: Murphy Kenneth M. , Heimberger Amy B. , Loh Dennis Y.
Published: October 2006

In order to examine the mechanisms by which clonal deletion of autoreactive T cells occurs, a peptide antigen was used to induce deletion of antigen-reactive thymocytes in vivo. Mice transgenic for a T cell receptor (TCR) that reacts to this peptide contain thymocytes that progress from the immature to the mature phenotype. Intraperitoneal administration of the peptide antigen to transgenic mice results in a rapid deletion of the immature CD4
+
CD8
+
TCR
lo
thymocytes. Apoptosis of cortical thymocytes can be seen within 20 hours of treatment. These results provide direct evidence for the in vivo role of apoptosis in the development of antigen-induced tolerance.
A Decade of Progress in Earth's Internal Properties and Processes
Authors: Anderson Orson L.
Published: October 2006

A major component of the Inter-Union Commission on Geodynamics Project, labeled "Internal Properties and Processes," included certain experimental and theoretical research in tectonophysics, seismology, geochemistry, petrology, volcanology, and planetology. This review focuses on a few research areas in which there have been surprises and reversals. In particular, attention is given to the attempts to quantify the thermal profile in the earth's interior and the material properties of the earth's interior.
The Marine Geochemistry of Germanium: Ekasilicon
Authors: Froelich Philip N. , Andreae Meinrat O.
Published: October 2006

The geochemical behavior of dissolved germanium in rivers, estuaries, and the oceans is similar to that of silicon. It is chemically weathered from continental rocks and transported by rivers to the oceans, where it is taken up by siliceous organisms and deposited in biogenic opal. The ratio of germanium to silicon buried in siliceous oozes must reflect the oceanic input ratios from rivers (crustal weathering) and sea-floor vents (mid-ocean ridge hydrothermal weathering). The opal germanium/silicon ratio may thus monitor relative variations in these weathering processes and provide information about the geochemical history of seawater.
Constraints on the Formation of Sedimentary Dolomite
Authors: Baker Paul A. , Kastner Miriam
Published: October 2006

The experimental replacement of calcite and aragonite by dolomite under a variety of conditions indicates that dolomitization can take place in marine and lacustrine environments under two conditions: (i) low dissolved sulfate concentrations and (ii) insubstantial contemporaneous silica diagenesis. Common sites for dolomite formation are areas where the dissolved sulfate concentration is reduced by microbial sulfate reduction, through the mixing of seawater with large amounts of fresh water, or where low-sulfate alkaline lacustrine environments prevail. Even under these conditions, dolomite formation may be inhibited by the concurrent transformation of opal-A (amorphous silica) to opal-CT (disordered cristobalite and tridymite), whereas the subsequent transformation of opal-CT to quartz favors the formation of dolomite.
Strategy for Radioactive Waste Disposal in Crystalline Rocks
Authors: Bredehoeft John D. , Maini Tidu
Published: October 2006

A strategy for waste disposal is proposed in which the repository would be situated in a crystalline rock mass beneath a blanket of sedimentary rocks whose ground-water flow characteristics are well understood. Such an approach exemplifies the concept of multiple barriers to the isolation of radioactive wastes from the biosphere. This strategy has the advantages that (i) ground-water flow within the sedimentary rocks can be investigated and modeled by conventional, well-understood theory and technology; (ii) under favorable circumstances, the flow system operates as an active barrier, so that a long migration path and extremely low flow rate to the biosphere can be assured; and (iii) since, in many locations, ground water is nonpotable, the possibility of future human intrusion can be minimized.
Pesticides: Insecticides and Fungicides Are Chitin Synthesis Inhibitors
Authors: Leighton Terrance , Marks Edwin , Leighton Frances
Published: October 2006

Several important groups of fungicides and insecticides are specific inhibitors of chitin synthesis in a
Phycomyces
enzyme system and in insect organ cultures. The recently discovered benzoylphenylurea insecticides, which prevent chitin synthesis in insect tissues, are apparently not direct-acting chitin synthetase inhibitors. These insecticides may prevent insect chitin synthesis by interfering with the proteolytic activation of the chitin synthetase zymogen.
Carotenoids Function in Photoperiodic Induction of Diapause in a Predacious Mite
Authors: Van Zon A. Q. , Overmeer W. P. J. , Veerman A.
Published: October 2006

Predacious mites fed for two generations solely on the eggs of wild-type spider mites responded normally to short day lengths by entering diapause. However, predacious mites fed for two generations on eggs of albino spider mites, which are completely devoid of carotenoids, did not respond to short-day photoperiods. Apparently carotenoids are essential for photoperiodic induction; possibly a carotenoid or carotenoid derivative functions as the photopigment concerned in photoperiodic light reception in these mites.
Chlorine Monoxide Radical, Ozone, and Hydrogen Peroxide: Stratospheric Measurements by Microwave Limb Sounding
Authors: Waters J. W. , Hardy J. C. , Jarnot R. F. , Pickett H. M.
Published: October 2006

Profiles of stratospheric ozone and chlorine monoxide radical (ClO) have been obtained from balloon measurements of atmospheric limb thermal emission at millimeter wavelengths. The ClO measurements, important for assessing the predicted depletion of stratospheric ozone by chlorine from industrial sources, are in close agreement with present theory, The predicted decrease of ClO at sunset was measured. A tentative value for the stratospheric abundance of hydrogen peroxide was also determined.
Hydrogen Storage Materials: Properties and Possibilities
Authors: Cohen R. L. , Wernick J. H.
Published: October 2006

The physics, chemistry, and possible applications of the storage of hydrogen in intermetallic reservoirs are discussed. Storage in the form of intermetallic hydrides can be safe and, where hydrogen has some special value as a fuel, economical. New pumps and refrigerators based on the heat of sorption of the hydrogen into the intermetallic are approaching commercial viability.
Vibrio damsela
, a Marine Bacterium, Causes Skin Ulcers on the Damselfish
Chromis punctipinnis
Authors: Love Milton , Teebken-Fisher Dixie , Hose Jo Ellen , Farmer J. J. , Hickman Frances W. , Fanning G. Richard
Published: October 2006

A previously undescribed marine bacterium,
Vibrio damsela
, was isolated from naturally occurring skin ulcers on a species of temperate-water damselfish, the blacksmith (
Chromis punctipinnis
). Laboratory infection of the blacksmith with
Vibrio damsela
produced similar ulcers.
Vibrio damsela
was pathogenic for four other species of damselfish but not for members of other families of fish. The bacterium has also been isolated from water and from two human wounds and may be a cause of human disease.
Evidence that the Head of Kinesin Is Sufficient for Force Generation and Motility in Vitro
Authors: Yang Joy T. , Saxton William M. , Stewart Russell J. , Raff Elizabeth C. , Goldstein Lawrence S. B.
Published: October 2006

Kinesin is a mechanochemical protein that converts the chemical energy in adenosine triphosphate into mechanical force for movement of cellular components along microtubules. The regions of the kinesin molecule responsible for generating movement were determined by studying the heavy chain of
Drosophila
kinesin, and its truncated forms, expressed in
Escherichia coli
. The results demonstrate that (i) kinesin heavy chain alone, without the light chains and other eukaryotic factors, is able to induce microtubule movement in vitro, and (ii) a fragment likely to contain only the kinesin head is also capable of inducing microtubule motility. Thus, the amino-terminal 450 amino acids of kinesin contain all the basic elements needed to convert chemical energy into mechanical force.
Deuterolysis of Amino Acid Precursors: Evidence for Hydrogen Cyanide Polymers as Protein Ancestors
Authors: Matthews Clifford , Nelson John , Varma Pratibha , Minard Robert
Published: October 2006

Deuterolysis experiments suggest that hydrogen cyanide polymers rather than aminoacetonitriles are major precursors of α-amino acids obtained from spark reactions and other studies on chemical evolution. These results are consistent with the hypothesis that the original heteropolypeptides on the earth were synthesized spontaneously from hydrogen cyanide and water without the intervening formation of α-amino acids.
Stable, Monomeric Variants of λ Cro Obtained by Insertion of a Designed β-Hairpin Sequence
Authors: Mossing Michael C. , Sauer Robert T.
Published: October 2006

λ Cro is a dimeric DNA binding protein. Random mutagenesis and a selection for Cro activity have been used to identify the contacts between Cro subunits that are crucial for maintenance of a stably folded structure. To obtain equivalent contacts in a monomeric system, a Cro variant was designed and constructed in which the antiparallel β-ribbon that forms the dimer interface was replaced by a β-hairpin. The engineered monomer has a folded structure similar to wild type, is significantly more stable than wild type, and exhibits novel half-operator binding activity.
Ultrastructure of 40-Million-Year-Old Insect Tissue
Authors: Poinar George O. , Hess Roberta
Published: October 2006

Examination of the ultrastructure of preserved tissue in the abdomen of a fossil fly (Mycetophilidae: Diptera) entombed in Baltic amber revealed recognizable cell organelles. Structures that corresponded to muscle fibers, nuclei, ribosomes, lipid droplets, endoplasmic reticulum, and mitochondria were identified with the transmission electron microscope. Preservation was attributed to inert dehydration as well as the presence of compounds in the original sap which functioned as natural fixatives. This evidence of cell organelles in fossilized soft tissues represent an extreme form of mummification since Baltic amber is considered to have formed about 40 million years ago.
2,3-Dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline: a Neuroprotectant for Cerebral Ischemia
Authors: Sheardown Malcolm J. , Nielsen Elsebet Ø. , Hansen Anker J. , Jacobsen Poul , Honoré Tage
Published: October 2006

2,3-Dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX) is an analog of the quinoxalinedione antagonists to the non-
N
-methyl-D-aspartate (non-NMDA) glutamate receptor. NBQX is a potent and selective inhibitor of binding to the quisqualate subtype of the glutamate receptor, with no activity at the NMDA and glycine sites. NBQX protects against global ischemia, even when administered 2 hours after an ischemic challenge.
Growth Factors Induce Phosphorylation of the Na
+
/H
+
Antiporter, a Glycoprotein of 110 kD
Authors: Sardet C. , Counillon L. , Franchi A. , Pouysségur J.
Published: October 2006

The Na
+
/H
+
antiporter, which regulates intracellular
p
H in virtually all cells, is one of the best examples of a mitogen- and oncogene-activated membrane target whose activity rapidly changes on stimulation. The activating mechanism is unknown. A Na
+
/H
+
antiporter complementary DNA fragment was expressed in
Escherichia coli
as a β-galactosidase fusion protein, and a specific antibody to the fusion protein was prepared. Use of this antibody revealed that the Na
+
/H
+
antiporter is a 110-kilodalton glycoprotein that is phosphorylated in growing cells. Mitogenic activation of resting hamster fibroblasts and A431 human epidermoid cells with epidermal growth factor, thrombin, phorbol esters, or serum, stimulated phosphorylation of the Na
+
/H
+
antiporter with a time course similar to that of the rise in intracellular
p
H.
Catastrophic Decline of a Top Carnivore in the Gulf of California Rocky Intertidal Zone
Authors: Dungan Michael L. , Miller Thomas E. , Thomson Donald A.
Published: October 2006

The predatory sun star,
Heliaster kubiniji
, once the commonest rocky intertidal asteroid of the Gulf of California, has been rare throughout this region since summer 1978 when a devastating disease outbreak occurred. This unprecedented phenomenon and several other exceptional ecological events in marine communities of the northeastern Pacific appear to be linked to large-scale climatic changes that occurred during 1977 and 1978. Implications of the decline in
Heliaster kubiniji
are discussed.
Stem Rust of Wheat 3300 Years Old Found in Israel
Authors: Kislev Mordechai E.
Published: October 2006

A fungus parasite observed on two ancient lemma fragments of wheat was identified as
Puccinia graminis
. The fragments were found in a storage jar from the Late Bronze Age excavated at Tel Batash, Israel, Uredia, hyphae, and germinating uredospores, though charred, were well preserved.
Disease-Suppressive Soil and Root-Colonizing Bacteria
Authors: Schroth Milton N. , Hancock Joseph G.
Published: October 2006

Soils in many areas suppress certain plant diseases. Understanding the basis for this disease suppressiveness could lead to improved plant health in less favorable areas. Some forms of disease suppression may be caused by bacteria in the genus
Pseudomonas
which aggressively colonize root surfaces. Increased plant growth and yield are closely associated with the capacity of some of these bacteria to produce iron-binding compounds called siderophores. This article addresses the biological characteristics of these soil-borne root epiphytes, their contribution to plant health, and their potential use in biotechnology.
β-Arrestin: a Protein that Regulates β-adrenergic Receptor Function
Authors: Lohse Martin J. , Benovic Jeffrey L. , Codina Juan , Caron Marc G. , Lefkowitz Robert J.
Published: October 2006

Homologous or agonist-specific desensitization of β-adrenergic receptors is thought to be mediated by a specific kinase, the β-adrenergic receptor kinase (βARK). However, recent data suggest that a cofactor is required for this kinase to inhibit receptor function. The complementary DNA for such a cofactor was cloned and found to encode a 418-amino acid protein homologous to the retinal protein arrestin. The protein, termed β-arrestin, was expressed and partially purified. It inhibited the signaling function of βARK-phosphorylated β-adrenergic receptors by more than 75 percent, but not that of rhodopsin. It is proposed that β-arrestin in concert with βARK effects homologous desensitization of β-adrenergic receptors.
Structure of Ribonuclease H Phased at 2 Å Resolution by MAD Analysis of the Selenomethionyl Protein
Authors: Yang Wei , Hendrickson Wayne A. , Crouch Robert J. , Satow Yoshinori
Published: October 2006

Ribonuclease H digests the RNA strand of duplex RNA⋅DNA hybrids into oligonucleotides. This activity is indispensable for retroviral infection and is involved in bacterial replication. The ribonuclease H from
Escherichia coli
is homologous with the retroviral proteins. The crystal structure of the
E. coli
enzyme reveals a distinctive α-β tertiary fold. Analysis of the molecular model implicates a carboxyl triad in the catalytic mechanism and suggests a likely mode for the binding of RNA⋅DNA substrates. The structure was determined by the method of multiwavelength anomalous diffraction (MAD) with the use of synchrotron data from a crystal of the recombinant selenomethionyl protein.
Polar Lipids of Archaebacteria in Sediments and Petroleums
Authors: Chappe B. , Albrecht P. , Michaelis W.
Published: October 2006

Glycerol tetraethers with head-to-head isoprenoid 40-carbon chains that are typical of archaebacteria, in particular of methanogens, were identified in the polar lipids of sediments and petroleums. These structures are at least partially preserved in the subsurface beyond the stage of petroleum formation. Their identification provides further evidence that a significant part of geological organic matter derives from the lipids of membranes of microorganisms.
Localization of a Circadian Pacemaker in the Eye of a Mollusc,
Bulla
Authors: Block Gene D. , Wallace Steven F.
Published: October 2006

The eye of the marine mollusc
Bulla
contains a circadian pacemaker which, along with critical entrainment pathways, is located among a small group of neurons at the base of the retina. Long-term intracellular recording from cells of the organized photoreceptor layer, which constitutes most of the retinal volume, indicates that these cells are not involved in generating the rhythm since rhythmic changes in membrane potential were not observed. In addition, surgical removal of the entire photoreceptor layer does not alter the period of the circadian rhythm and does not prevent phase shifts by light pulses.
Mechanism and Stereoselectivity of Asymmetric Hydrogenation
Authors: Halpern Jack
Published: October 2006

Rhodium complexes containing chiral phosphine ligands catalyze the hydrogenation of olefinic substrates such as α-aminoacrylic acid derivatives, producing chiral products with very high optical yields. Elucidation of the mechanisms of such reactions leads to the conclusion that the stereoselection is dictated not by the preferred initial binding of the substrate to the chiral catalyst, but rather by the much higher reactivity of the minor diastereomer of the catalyst-substrate adduct corresponding to the less favored binding mode.
Recognition of a Hidden Mineral Deposit by an Artificial Intelligence Program
Authors: Campbell A. N. , Hollister V. F. , Duda R. O. , Hart P. E.
Published: October 2006

A computer program that uses artificial intelligence techniques has successfully identified the location of a porphyry molybdenum deposit. Given geological maps of readily available predrilling exploration data for Mount Tolman in Washington State and using rules obtained from a porphyry molybdenum exploration specialist, the program (called PROSPECTOR) identified the location of previously unknown ore-grade mineralization. This appears to be the first reported determination of the location of mineralization by such a computer-based approach.
Catalytic Processes in the Atmospheres of Earth and Venus
Authors: DeMore W. B. , Yung Yuk L.
Published: October 2006

Photochemical processes in planetary atmospheres are strongly influenced by catalytic effects of minor constituents. Catalytic cycles in the atmospheres of Earth and Venus are closely related. For example, chlorine oxides (CIO

x

) act as catalysts in the two atmospheres. On Earth, they serve to convert odd oxygen (atomic oxygen and ozone) to molecular oxygen. On Venus they have a similar effect, but in addition they accelerate the reactions of atomic and molecular oxygen with carbon monoxide. The latter process occurs by a unique combination of CIO

x

catalysis and sulfur dioxide photosensitization. The mechanism provides an explanation for the very low extent of carbon dioxide decomposition by sunlight in the Venus atmosphere.
Wilms Tumor Locus on 11p13 Defined by Multiple CpG Island-Associated Transcripts
Authors: Bonetta Laura , Kuehn Stephen E. , Huang Annie , Law David J. , Kalikin Linda M. , Koi Minoru , Reeve Anthony E. , Brownstein Bernard H. , Yeger Herman , Williams Bryan R. G. , Feinberg Andrew P.
Published: October 2006

Wilms tumor is an embryonal kidney tumor involving complex pathology and genetics. The Wilms tumor locus on chromosome 11p13 is defined by the region of overlap of constitutional and tumor-associated deletions. Chromosome walking and yeast artificial chromosome (YAC) cloning were used to clone and map 850 kilobases of DNA. Nine CpG islands, constituting a "CpG island archipelago," were identified, including three islands that were not apparent by conventional pulsed-field mapping, and thus were at least partially methylated. Three distinct transcriptional units were found closely associated with a CpG island within the boundaries of a homozygous DNA deletion in a Wilms tumor.
Relation of Soil Water Movement and Sulfide Concentration to
Spartina alterniflora
Production in a Georgia Salt Marsh
Authors: King Gary M. , Klug M. J. , Wiegert R. G. , Chalmers A. G.
Published: October 2006

It is proposed that differences in plant height and productivity of the salt-marsh cordgrass
Spartina alterniflora
are the result of a dynamic interaction among tidal water movement, dissolved iron and sulfide concentrations in marsh soils, and bacterial sulfate reduction. Tidal water movement regulates the input of iron into marsh soils and the drainage of sulfide-containing interstitial water, and thereby controls the concentration of dissolved sulfide formed as a result of bacterial sulfate reduction. Near tidal creeks, where water movement and plant height and production are greatest, sulfide concentrations are lowest; in more elevated regions of marsh, where water movement and plant production are least, sulfide concentrations are highest. Plant height and productivity may be limited by the effects of sulfide on nutrient uptake.
Plant Productivity and Environment
Authors: Boyer J. S.
Published: October 2006

An analysis of major U.S. crops shows that there is a large genetic potential for yield that is unrealized because of the need for better adaptation of the plants to the environments in which they are grown. Evidence from native populations suggests that high productivity can occur in these environments and that opportunities for improving production in unfavorable environments are substantial. Genotypic selection for adaptation to such environments has already played an important role in agriculture, but the fundamental mechanisms are poorly understood. Recent scientific advances make exploration of these mechanisms more feasible and could result in large gains in productivity.
Shuttle Imaging Radar Experiment
Authors: Elachi C. , Brown W. E. , Cimino J. B. , Dixon T. , Evans D. L. , Ford J. P. , Saunders R. S. , Breed C. , Masursky H. , McCauley J. F. , Schaber G. , Dellwig L. , England A. , MacDonald H. , Martin-Kaye P. , Sabins F.
Published: October 2006

The shuttle imaging radar (SIR-A) acquired images of a variety of the earth's geologic areas covering about 10 million square kilometers. Structural and geomorphic features such as faults, folds, outcrops, and dunes are clearly visible in both tropical and arid regions. The combination of SIR-A and Seasat images provides additional information about the surface physical properties: topography and roughness. Ocean features were also observed, including large internal waves in the Andaman Sea.
The Human Genome Project: Past, Present, and Future
Authors: Watson James D.
Published: October 2006

This article presents a short discussion of the development of the human genome program in the United States, a summary of the current status of the organization and administration of the National Institutes of Health component of the program, and some prospects for the future directions of the program and the applications of genome information.
Activation of
ras
Oncogenes Preceding the Onset of Neoplasia
Authors: Kumar Ramesh , Sukumar Saraswati , Barbacid Mariano
Published: October 2006

The identification of
ras
oncogenes in human and animal cancers including precancerous lesions indicates that these genes participate in the early stages of neoplastic development. Yet, these observations do not define the timing of
ras
oncogene activation in the multistep process of carcinogenesis. To ascertain the timing of
ras
oncogene activation, an animal model system was devised that involves the induction of mammary carcinomas in rats exposed at birth to the carcinogen nitrosomethylurea. High-resolution restriction fragment length polymorphism analysis of polymerase chain reaction-amplified
ras
sequences revealed the presence of both H-
ras
and K-
ras
oncogenes in normal mammary glands 2 weeks after carcinogen treatment and at least 2 months before the onset of neoplasia. These
ras
oncogenes can remain latent within the mammary gland until exposure to estrogens, demonstrating that activation of
ras
oncogenes can precede the onset of neoplasia and suggesting that normal physiological proliferative processes such as estrogen-induced mammary gland development may lead to neoplasia if the targeted cells harbor latent
ras
oncogenes.
Very-Long-Baseline Radio Interferometry: The Mark III System for Geodesy, Astrometry, and Aperture Synthesis
Authors: Rogers Alan E. E. , Cappallo Roger J. , Hinteregger Hans F. , Levine James I. , Nesman Edwin F. , Webber John C. , Whitney Alan R. , Clark Thomas A. , Ma Chopo , Ryan James , Corey Brian E. , Counselman Charles C. , Herring Tomas A. , Shapiro Irwin I. , Knight Curtis A. , Shaffer David B. , Vandenberg Nancy R. , Lacasse Richard , Mauzy Robert , Rayhrer Benno , Schupler Bruce R. , Pigg J. C.
Published: October 2006

The Mark III very-long-baseline interferometry (VLBI) system allows recording and later processing of up to 112 megabits per second from each radio telescope of an interferometer array. For astrometric and geodetic measurements, signals from two radio-frequency bands (2.2 to 2.3 and 8.2 to 8.6 gigahertz) are sampled and recorded simultaneously at all antenna sites. From these dual-band recordings the relative group delays of signals arriving at each pair of sites can be corrected for the contributions due to the ionosphere. For many radio sources for which the signals are sufficiently intense, these group delays can be determined with uncertainties under 50 picoseconds. Relative positions of widely separated antennas and celestial coordinates of radio sources have been determined from such measurements with 1 standard deviation uncertainties of about 5 centimeters and 3 milliseconds of arc, respectively. Sample results are given for the lengths of baselines between three antennas in the United States and three in Europe as well as for the arc lengths between the positions of six extragalactic radio sources. There is no significant evidence of change in any of these quantities. For mapping the brightness distribution of such compact radio sources, signals of a given polarization, or of pairs of orthogonal polarizations, can be recorded in up to 28 contiguous bands each nearly 2 megahertz wide. The ability to record large bandwidths and to link together many large radio telescopes allows detection and study of compact sources with flux densities under 1 millijansky.