bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent Recession of Tropical Cliffy Coasts
Authors: Russell Richard J.
Published: October 2006

My fieldwork in various parts of the world leads me to the conclusion that the retreat of cliffy coasts through abrasion and solutional erosion during Recent times has produced a whole complex of forms, including conspicuous benches well above sea level where bedrock conditions are favorable. In addition, flats of other origin are being developed at various levels. Broad exposures of beach rock are a marine phenomenon only in that such exposure is a result of beach recession and of the uncovering of materials that had been cemented, under freshwater conditions, along water tables, in some places 6 or more feet above sea level. Contemporary coral and algal flats are forming in some instances several feet above the level of the highest tides.
Neurogenic Component of Chronic Renal Hypertension
Authors: McCubbin James W. , Page Irvine H.
Published: October 2006

Infusion of angiotensin or renin in small quantities affects the sympathetic nervous system so that responses are increased to either drugs or reflexes that cause release of norepinephrine at nerve endings. Response to injected norepinephrine is relatively unchanged. This action of angiotensin is dependent upon an intact sympathetic nervous system. The direct vasoconstrictor action of angiotensin is not an essential part of the enhanced response. The phenomenon was shown to have relevance to acute and chronic experimental renal hypertension in dogs by the fact that in both the pressor response to tyramine was enhanced. We believe that the ability of angiotensin to intensify the effect of normal neurogenic vasomotor activity, along with an upward reset of the carotid sinus buffer mechanism, might account importantly for the neurogenic component of renal hypertension.
Resistance to DDT in the Mosquito Fish,
Gambusia affinis
Authors: Vinson S. Bradleigh , Boyd Claude E. , Ferguson Denzel E.
Published: October 2006

Mosquito fish from waters near cotton fields that have had a long history of treatment with chlorinated hydrocarbon pesticides exhibited a marked resistance to DDT compared with fish from areas which had had no past exposure to insecticides.
Binasal Hemianopia as an Early Stage in Binocular Color Rivalry
Authors: Crovitz Herbert F. , Lipscomb D. Barry
Published: October 2006

Fifty years ago Köllner reported that the initial fleeting sensation in binocular color rivalry is a bipartite color field such that the color presented to the left eye appears to the left of the color presented to the right eye. A method is described for maintaining such quasi hemianopia for long periods of time.
Alkanes in Natural and Synthetic Petroleums: Comparison of Calculated and Actual Compositions
Authors: Friedel R. A. , Sharkey A. G.
Published: October 2006

A similarity exists between the low molecular weight alkane isomers in crude oil and Fischer-Tropsch catalytic synthesis products. The composition of the C
4
through C
7
alkane isomers in a crude oil was calculated quantitatively with the equations previously used to calculate the alkane isomers in Fischer-Tropsch products. These results may have significance in ascertaining the origin of the volatile hydrocarbons in crude oils.
Involvement of RNA in the Synthesis of Proteins
Authors: Watson J. D.
Published: October 2006

We can now have considerable confidence that the broad features of protein synthesis are understood. The involvement of RNA is very much more complicated than was imagined in 1953. There is not one functional RNA. Instead, protein synthesis demands the ordered interaction of three classes of RNA—ribosomal, soluble, and messenger. Many important questions, however, remain unanswered. For instance, there is no theoretical framework for the ribosomal subunits, nor for that matter, do we understand the functional significance of ribosomal RNA. Most satisfying is the realization that all the steps in protein replication will be shown to involve well-understood chemical forces. As yet we do not know all the details. For example, are the DNA base pairs involved in messenger RNA selection of the corresponding amino-acyl-sRNA? With luck, this will soon be known. We can thus have every expectation that future progress in understanding selective protein synthesis (and its consequences for embryology) will have a similarly well-defined and, when understood, easy-to-comprehend chemical basis.
Marsilea vestita
: Conversion of the Water Form to the Land Form by Darkness and by Far-Red Light
Authors: Gaudet John J.
Published: October 2006

A period in darkness or in continuous far-red light can cause the ferns of the species
Marsilea vestita
Hook. and Grev. to develop as a land form in a medium which normally allows only the water form to develop. Far-red light is more effective than darkness in causing this conversion. The difference in the quality of light reaching plants growing in water or on land may cause this conversion to occur in nature.
Endotrophic Mycorrhizae Influence Yellow Poplar Seedling Growth
Authors: Clark F. Bryan
Published: October 2006

Yellow poplar seedlings infected with endotrophic mycorrhizal fungi grow much faster than seedlings grown without mycorrhizae. A method of pot culture that uses natural soil structure provides an excellent means of studying growth differences due to microorganisms.
Cell Culture Perfusion Chamber: Adaptation for Microscopy of Clonal Growth
Authors: Freed Jerome J.
Published: October 2006

Silicone rubber O-rings used as gaskets in Sykes-Moore cell culture perfusion chambers are permeable to carbon dioxide. When small numbers of cells are planted in such chambers, loss of carbon dioxide leads to an undesirable increase in
p
H and inhibits cell multiplication. Substitution of Teflon O-rings prevents this loss and allows a constant carbon dioxide tension to be maintained within the chamber. The rate of growth and plating efficiency of small numbers of cells planted in the modified chambers have been found to be comparable to those observed in conventional culture vessels. The necessary additional parts of the chamber are described, and the modifications in procedure outlined.
Cardiovascular Responses of the Chicken to Seasonal and Induced Temperature Changes
Authors: Vogel James A. , Sturkie Paul D.
Published: October 2006

Blood pressure and cardiac output decline as ambient temperature rises in birds acclimatized to both seasonal- and induced-temperature changes, in contrast to the response usually observed in unacclimatized mammals. The decline in chickens is due to a lowered vascular resistance and blood volume. These circulatory adjustments may be related to the fact that excess heat in birds is dissipated through the respiratory system rather than through the skin.
Transformation of Montmorillonite to Kaolinite during Weathering
Authors: Altschuler Z. S. , Dwornik E. J. , Kramer Henry
Published: October 2006

Extensive deposits of kaolinite in Florida are formed by transformation of montmorillonite during low-temperature supergene weathering. The transformation occurs by intracrystalline leaching of interlayer cations and tetrahedral silica layers. Interposition of stripped layers within montmorillonite creates a regular 1:1 mixedlayered montmorillonite-kaolinite, a new clay structure. Kaolin-like layers are nourished by lateral epitaxy, as the iron-rich montmorillonite decomposes. Hexagonal outgrowths of new kaolinite develop at the edges of montmorillonite flakes and nucleate new vertical growth. Kaolinitic sands impregnated with goethite are ultimately formed, and the released silica enriches groundwater and forms secondary chert.
Pontine Reticular Formation: Relation to Lateral Geniculate Nucleus during Deep Sleep
Authors: Bizzi Emilio , Brooks Dana C.
Published: October 2006

Irregular groups of monophasic waves (seven waves per second) appear synchronously in the pontine reticular, formation and in the lateral geniculate nucleus during the deep (low-voltage, fast) phase of sleep. The geniculate potentials can be triggered by low-rate stimulation of the pontine reticular formation, but the reverse effect has never been obtained.
High Pressure X-ray Diffraction Studies on Barium
Authors: Barnett J. Dean , Bennion Roy B. , Hall H. Tracy
Published: October 2006

Simultaneous x-ray diffraction and electrical resistance measurements on barium establish, with certainty, that Bridgman's 78-kb resistance transition is identical with his 59-kb volume transition. During this transition, the body-centered cubic structure changes to hexagonal-close packed. Lattice parameters for the latter structure at 62 kb (volume scale) are:
a
= 3.90 Å,
c
= 6.15 Å, and
c
/
a
= 1.58. Compression (ΔV/V
0
) at 62 kb is 0.359 ± 0.005 compared to 0.345 previously reported by Bridgman. Below the transition, at 49 kb, compression is 0.300 ± 0.005 compared to Bridgman's 0.288. Bridgman's 17-kb volume transition was not detected by x-ray diffraction.
Startle Reaction: Modification by Background Acoustic Stimulation
Authors: Hoffman Howard S. , Fleshler Morton
Published: October 2006

Six rats were exposed to a sequence of gunshot-like acoustical bursts during silence, during steady noise, and during pulsed noise. Assessment of their startle reactions to the bursts revealed that a background of steady noise enhanced the response, whereas a background of pulsed noise produced suppression of response. It is hypothesized that pulsed noise causes a relative refractory state in the mechanisms responsible for startle and that steady noise may enhance startle by masking uncontrolled punctiform acoustic stimuli.
Light-Induced Inhibition of Potato Tuber Sprouting
Authors: Dinkel Donald H.
Published: October 2006

In freshly harvested Alaska-grown potato tubers there is a "rest period" during which time no sprout growth can be visibly detected. This is followed by a physiological stage of development when sprout growth will occur in the dark but is suppressed by light. Following this is a stage of gradual resumption of growth of light-suppressed sprouts and a lessening of the inhibitory responses in tubers planted at successive lengthening periods of time after harvest.
Actinomycin D Effects in Frog Embryos: Evidence for Sequential Synthesis of DNA-Dependent RNA
Authors: Flickinger Reed A.
Published: October 2006

Early gastrulae of
Rana pipiens
exposed to actinomycin D for 2 days were then cultured in saline. The resulting larvae were immotile; histological examination revealed impaired development of axial nerve and muscle tissues, but normal differentiation of sensory, pronephric, heart, and digestive tissues; this suggests sequential synthesis of the different tissue-specific molecules of DNA-dependent RNA.
Electric Fields across Water-Nitrobenzene Interfaces
Authors: Blank Martin , Feig Steven
Published: October 2006

Surface-active ions in water-nitrobenzene systems accumulate at the interface in electric fields. Two separate mechanisms can be distinguished. One is similar to the classical electrocapillary adsorption and the other is operative when there is appreciable transference across the interface. The magnitude of the interfacial barrier to transport determines which mechanism operates.
Luminescent "Crystalline" Particles: An Organized Subcellular Bioluminescent System
Authors: De Sa Richard , Hastings J. W. , Vatter A. E.
Published: October 2006

A new type of intracellular biological particle which is functional in light emission has been discovered and isolated. As seen with the electron microscope it resembles a crystal; moreover, its high degree of birefringence suggests crystallinity. Isolated particles can be caused to emit a luminescent flash that resembles the flash emitted by the dinoflagellate,
Gonyaulax polyedra
. The particles are referred to as "scintillons".
Indoleacetamide as an Intermediate in the Synthesis of Indoleacetic Acid in
Pseudomonas savastanoi
Authors: Magie Allan R. , Wilson E. E. , Kosuge T.
Published: October 2006

When DL-tryptophan-2-C
14
was incubated with washed cells or cell-free preparations of
Pseudomonas savastanoi
, two radioactive metabolites were formed. One was identified as indoleacetamide and the second, indoleacetic acid. The amount of indoleacetamide in the reaction mixture increased rapidly during the early stages of incubation; it reached a peak after 15 minutes and declined steadily thereafter. Indoleacetic acid, on the other hand, accumulated slowly throughout the incubation period. Cell-free preparations preferentially utilize the L-isomer of tryptophan for the synthesis of indoleacetamide and indoleacetic acid. The results of these experiments suggest, therefore, that
P. savastanoi
synthesizes indoleacetic acid by the following reactions: L-tryptophan→indoleacetamide→indoleacetic acid.
Discovery of a Peptide-Based Renin Inhibitor with Oral Bioavailability and Efficacy
Authors: Kleinert Hollis D. , Rosenberg Saul H. , Baker William R. , Stein Herman H. , Klinghofer Vered , Barlow Jennifer , Spina Kenneth , Polakowski James , Kovar Peter , Cohen Jerome , Denissen Jon
Published: October 2006

Peptidic renin inhibitors have been poorly absorbed across the intestine or rapidly eliminated by the liver and have been reported to have oral bioavailabilities of less than 2%. A peptide-based renin inhibitor, A-72517 (molecular mass of 706 daltons), was devised that has oral bioavailabilities of 8, 24, 32, and 53% in the monkey, rat, ferret, and dog, respectively. Dose-related reductions in blood pressure, plasma renin activity, and plasma angiotensin II in parallel with increased plasma drug concentrations were observed after oral administration of A-72517 to conscious, salt-depleted dogs. Thus, peptide-based molecules of sizable molecular mass can be absorbed intact into the systemic circulation of animals. These findings support the potential of peptide-based drugs for oral administration.
X-Ray Laser Microscopy of Rat Sperm Nuclei
Authors: Da Silva L. B. , Trebes J. E. , Balhorn R. , Mrowka S. , Anderson E. , Attwood D. T. , Barbee T. W. , Brase J. , Corzett M. , Gray J. , Koch J. A. , Lee C. , Kern D. , London R. A. , MacGowan B. J. , Matthews D. L. , Stone G.
Published: October 2006

The development of high brightness and short pulse width (< 200 picoseconds) x-ray lasers now offers biologists the possibility of high-resolution imaging of specimens in an aqueous environment without the blurring effects associated with natural motions and chemical erosion. As a step toward developing the capabilities of this type of x-ray microscopy, a tantalum x-ray laser at 44.83 angstrom wavelength was used together with an x-ray zone plate lens to image both unlabeled and selectively gold-labeled dried rat sperm nuclei. The observed images show ∼500 angstrom features, illustrate the importance of x-ray microscopy in determining chemical composition, and provide information about the uniformity of sperm chromatin organization and the extent of sperm chromatin hydration.
Simazine: Degradation by Soil Microorganisms
Authors: Kaufman Donald D. , Kearney Philip C. , Sheets Thomas J.
Published: October 2006

A soil fungus,
Aspergillus fumigatus
Fres., is effective in the degradation of the herbicide 2-chloro-4,6-bis(ethylamino)-
s
-triazine (simazine). The degradation of both ring- and chain-labeled (C
14
) simazine was observed in an unamended and an amended (sucrose) basal medium. A loss of C
14
occurred in all culture solutions containing either ring- or chain-labeled simazine, but the decrease in activity observed was greater with chain-labeled than with ring-labeled simazine. Chromatographic evidence indicates that
A. fumigatus
may possess a degradation mechanism unlike that which occurs in corn plants.
Steric Factors in the Chemistry of Polypeptides, Poly-α-Amino Acids and Proteins
Authors: Whitfield Robert E.
Published: October 2006

An application of the rule of six for the estimation of steric hindrance in reactions of dipeptides and polypeptides, and conformational preferences of polypeptides and proteins, is described.
Chlorinated Insecticides in the Body Fat of People in the United States
Authors: Dale William E. , Quinby Griffith E.
Published: October 2006

Benzene hexachloride and dieldrin are present in the body fat of people in the general population of the United States. The mean concentration of dieldrin is 0.15 ± 0.02 parts per million, which is in good agreement with the concentration reported for southern England. The mean concentration of benzene hexachloride is 0.20 ± 0.04 ppm, which is considerably lower than the mean concentration reported for France. Paired analyses of DDT by gas chromatographic and colorimetric methods show that the results of the latter may give incorrectly high results when applied to human fat.
Symbiosis: On the Role of Algae Symbiotic with Hydra
Authors: Muscatine Leonard , Lenhoff Howard M.
Published: October 2006

Green algae living within gastrodermal cells of hydra photosynthetically incorporate C
11
O
2
. About 10 percent of the carbon fixed by the algae is released to the hydra where it is assimilated into animal cell components. The specific activity (counts per minute per microgram of protein nitrogen) of hydra animal tissue is 50 to 100 times greater than that of algae-free controls exposed to C
14
O
2
. Analyses were facilitated by a new method for rapid separation of hydra tissue layers.
Electron Microscopy of the Replicative Form of the DNA of the Bacteriophage ϕX174
Authors: Kleinschmidt Albrecht K. , Burton Alice , Sinsheimer Robert L.
Published: October 2006

Electron micrographs of surface films containing the replicative form of the DNA of bacteriophage, φX174 show ring structures, whose average contour length is 1.64 μ, which have the characteristic appearance of double-stranded DNA throughout most of their length.
Pea Aphid: Rearing on a Chemically Defined Diet
Authors: Auclair Jacques L. , Cartier Jean Jacques
Published: October 2006

Pea aphids,
Acyrthosiphon pisum
(Harr.), reared for two successive generations on a diet made of 23 amino acids and amides, 11 water-soluble vitamins, 35 percent sucrose, salts, and cholesterol, remained apterous. They grew and developed during the first generation almost as well as those grown on pea plants, with very little mortality.
Bending Waves of the Posterior Flagellum of
Ceratium
Authors: Brokaw C. J. , Wright Leigh
Published: October 2006

Flagellar bending waves, as shown by multiple-flash photomicrographs of the posterior flagellum of
Ceratium
, are not sine waves. The bent regions are circular arcs; these regions are separated by short segments without bending.
Behavior of Adult Rats Is Modified by the Experiences Their Mothers Had as Infants
Authors: Denenberg Victor H. , Whimbey Arthur E.
Published: October 2006

Some rat pups were handled for 20 days in infancy, while others were not. When the rats reached adulthood the females were bred. Some of the offspring were left with their natural mothers, others were fostered to mothers of the same background (handled/nonhandled) as that of their natural mothers, while still others were fostered to mothers with a different background from that of their natural mothers. The offspring were weaned and weighed at 21 days; at 50 days, activity and defecation scores were obtained in the open field. The weights at weaning and the defecation scores at 50 days were significantly influenced by the experience in infancy of the "postnatal" mother, whether she was the natural mother or a foster mother. The natural mother and the foster mother jointly affected the open-field activity of the offspring.
Inhibition of Antibody Synthesis by L-Phenylalanine
Authors: Ryan Wayne L. , Carver Michael J.
Published: October 2006

Antibody synthesis in response to the injection of diphtheria toxoid into rabbits and rats was used to study the effects of an excess of the amino acid L-phenylalanine on protein synthesis. Injections of phenylalanine produced a marked inhibition of antibody synthesis in both the rat and the rabbit. The dosage of phenylalanine used caused an increase over the normal concentration of phenylalanine in the plasma and spleen of rats, but did not cause a loss of weight or serum protein changes in the treated animals.
Reciprocal Activities of the Ventromedial and Lateral Hypothalamic Areas of Cats
Authors: Oomura Yutaka , Kimura Katsumi , Ooyama Hiroshi , Maeno Takashi , Iki Matasaburo , Kuniyoshi Makoto
Published: October 2006

Statistical treatment of recordings of spontaneous unit discharges from the ventromedial nucleus and the lateral area of the hypothalamus (the activities in one area being recorded while the other was stimulated) revealed significant reciprocal relations. The concept that glucose-sensitive neurons are present in the ventromedial nucleus was supported by the effects on the spontaneous unit discharges of injecting glucose and other solutions intravenously.
Homeostasis of the Nonfat Components of Migrating Birds
Authors: Odum Eugene P. , Rogers David T. , Hicks David L.
Published: October 2006

Obesity in migratory birds appears to differ from obesity in man in that gains and losses in body weight do not involve changes in the tissue structure of the body; fat is added to and used from preexisting tissue spaces without appreciable change in the water content or the nonfat dry weight of the body as a whole. Evidence is presented which supports the hypothesis that the nonfat body is essentially homeostatic during migration despite very large scale changes in total body weight.
Cerebellar Ataxia in Hamsters Inoculated with Rat Virus
Authors: Kilham Lawrence , Margolis George
Published: October 2006

Chronic ataxia associated with hypoplasia of the cerebellum was induced by intracerebral inoculation of newborn hamsters with various strains of rat virus. The condition usually became recognizable within 3 weeks of inoculation and remained static as the animals matured. Preliminary studies suggest that hypoplasia is induced by the rat virus acting on the outer germinal layer of the cerebellum at a critical time in its ontogenic development.
Pleistocene Wood Rat Middens and Climatic Change in Mohave Desert: A Record of Juniper Woodlands
Authors: Wells Philip V. , Jorgensen Clive D.
Published: October 2006

Leafy twigs and seeds of juniper are abundant in nine ancient
Neotoma
middens discovered in low, arid, desert ranges devoid of junipers, near Frenchman Flat, Nevada. Existing vegetation is creosote bush and other desert shrubs. Twelve radiocarbon dates suggest that the middens were deposited between 7800 to more than 40,000 years ago. Dominance of Utah juniper and absence of pinyon pine in most deposits indicates a local Pleistocene woodland climate more arid than the usual pinyon-juniper climate.
Submicrometer Intracellular Chemical Optical Fiber Sensors
Authors: Tan Weihong , Shi Zhong-You , Smith Steve , Birnbaum Duane , Kopelman Raoul
Published: October 2006

A thousandfold miniaturization of immobilized optical fiber sensors, a millionfold or more sample reduction, and at least a hundredfold shorter response time, all simultaneously, were achieved by combining nanofabricated optical fiber tips with near-field photopolymerization. Specifically, pH optical fiber sensors were prepared with internal calibration, making use of the differences in both fluorescence and absorption of the acidic and basic dye species. The submicrometer sensors have excellent detection limits, as well as photostability, reversibility, and millisecond response times. Successful applications include intracellular and intraembryonic measurements. Potential applications include spatially and temporally resolved chemical analysis and kinetics inside single biological cells and their substructures.
Prevalence of AIDS-Related Risk Factors and Condom Use in the United States
Authors: Catania Joseph A. , Coates Thomas J. , Stall Ron , Turner Heather , Peterson John , Hearst Norman , Dolcini M. Margaret , Hudes Estie , Gagnon John , Wiley James , Groves Robert
Published: October 2006

A national probability survey of human immunodeficiency virus (HIV)-related risk factors among the general heterosexual population, the National AIDS (acquired immunodeficiency syndrome) Behavioral Surveys, has obtained data from 10,630 respondents. Data are presented on the prevalence of HIV-related risks in the general heterosexual population, on the distribution of the three largest risk groups across social strata, and on the prevalence and distribution of condom use among heterosexuals reporting a risk factor. Between 15 and 31 percent of heterosexuals nationally and 20 and 41 percent in cities with a high prevalence of AIDS reported an HIV risk factor. Condom use was relatively low. Only 17 percent of those with multiple sexual partners, 12.6 percent of those with risky sexual partners, and 10.8 percent of untested transfusion recipients used condoms all the time. Overall, the results suggest that current HIV prevention programs have, to a very limited extent, reached those heterosexuals with multiple sexual partners but have failed to reach many other groups of the heterosexual population at risk for HIV. New public health strategies may be needed for these specific risk groups.
Pteropod Ooze from Bermuda Pedestal
Authors: Chen Chin
Published: October 2006

Twenty pteropod species and two subspecies are present in the Bermuda Pedestal pelagic sediments. Some species having thin, fragile shells were absent from the sediments but present in the deep water off Bermuda. The subarctic species was present only in the sediments, which indicates that the subarctic current probably invaded the Bermuda region some time ago.
Ferric Tourmaline from Mexico
Authors: Mason Brian , Donnay Gabrielle , Hardie L. A.
Published: October 2006

Dark brown crystals, up to 10 mm long, occur in rhyolite at Mexquitic, San Luis Potosi, Mexico. They are short prismatic, showing {112̅0}, {303̅0}, {101̅1}, {022̅1}, with
c
/
a
0.4521, measured with a goniometer, and distinct {112̅0} cleavage. With an unusual combination of cell dimensions, high density, high refractive indices, and extreme birefringence, this tourmaline falls outside the known elbaite-schorl and schorl-dravite series. A chemical analysis, recalculated on the basis of cell volume and density, gives close to the theoretical 150 atoms per cell, whether the iron is ferrous or ferric, but the physical properties indicate a ferric tourmaline.
Isolation of an Antihistaminic Principle Resembling Tomatine from Crown Gall Tumors
Authors: Kovacs B. A. , Wakkary J. A. , Goodfriend L. , Rose B.
Published: October 2006

Antihistaminic activity was demonstrated previously in extracts of crown gall tumors by assaying in vivo. A crystalline substance isolated from the crude extracts has now been found to possess a high degree of potency against histamine, acetylcholine, bradykinin, and serotonin when assayed in vitro. The chemical characteristics of the substance resemble closely those of tomatine. When tomatine was investigated, it was found to have biological properties similar to those of the crystalline substances isolated from crown gall tumors. It seems likely that the antihistaminic properties of crown-gall tumor extracts are due to tomatine or a substance which closely resembles it.
House Sparrows: Rapid Evolution of Races in North America
Authors: Johnston Richard F. , Selander Robert K.
Published: October 2006

Conspicuous adaptive differentiation in color and size has occurred in the house sparrow (
Passer domesticus
) in North America and the Hawaiian Islands since its introduction in the middle of the 19th century. Patterns of geographic variation in North America parallel those shown by native polytypic species, in conformity with Gloger's and Bergmann's ecogeographic rules. Racial differentiation of house sparrow populations may require no more than 50 years.
Spleen-Colony Formation in Anemic Mice of Genotype

WW
V
Authors: McCulloch E. A. , Siminovitch L. , Till J. E.
Published: October 2006

The hemopoietic cells from anemic mice of genotype
WW

v

are less able by 200-fold to take part in colony formation in the spleen than cells from the normal littermates of genotype
ww
. The genetic defect shows itself in the colony-forming cells, since cells from normal littermate mice form colonies in the spleens of unirradiated mice of genotype
WW

v

. Use of animals of genotype
WW

v

as recipients improves the spleen-colony method by removing bias resulting from the death of irradiated recipients.
Markovian Model of Time Patterns of Speech
Authors: Jaffe Joseph , Cassotta Louis , Feldstein Stanley
Published: October 2006

The time pattern of speech is describable as a first-order Markov process when presence or absence is sampled at a rate of 200 times per minute. Two types of monolog were generated under different conditions of environmental constraint. Although both fit the model, estimates of their mean range of statistical dependency differed significantly.
Circadian Leaf Movements: Persistence in Bean Plants Grown in Continuous High-Intensity Light
Authors: Hoshizaki Takashi , Hamner K. C.
Published: October 2006

A circadian leaf movement has been found in
Phaseolus vulgaris
var. Pinto that will persist under constant temperature and continuous fluorescent light. The period of leaf movement was approximately 26 hours in length, and the amplitude did not diminish for at least 4 weeks. Leaf movements were similar for plants grown in either 1100, 4950, 7700, or 10,450 lumens per square meter. This is the first clearly defined persistent circadian rhythm reported for leaves of higher plants.
Oysters: Composition of the Larval Shell
Authors: Stenzel H. B.
Published: October 2006

The shell of the free-swimming veliger larval stage of the common North American oyster
Crassostrea virginica
(Gmelin, 1791) is composed of aragonite. This composition contrasts with that of the adult shell, which is composed mainly of calcite, the rhombohedral allomorph of calcium carbonate, and minor amounts of aragonite.
High Pressure: Effect on Dysprosium
Authors: Souers P. C. , Jura G.
Published: October 2006

The electrical resistance of dysprosium was studied in the temperature-pressure range 77° to 200°K and 15 to 120 kb. The variations of the Néel transition with pressure was found to good accuracy, the value of d
T
N
/d
P
being -0.62± 0.4 deg/kb. From this result, second-order thermodynamic equations yield values of -64 × 10
-6
(°C)
-1
and 4.0 × 10
-14
cm
2
/dyne for the changes in the coefficient of linear expansion and the compressibility, respectively, at the 1-atm Néel point. The Néel transition disappears at 45 to 55 kb, and no magnetic transitions are seen at higher pressures in the temperature range indicated. The other boundaries in the region investigated have been determined but are very uncertain. The cause of the cusp in the isothermal compressions is not clear from the available data. Above the Néel boundary, the pressure dependence of the cusp with respect to temperature, d
P
/d
T
, is very small and may even be zero. Below the Néel temperature, d
P
/d
T
is uncertain. From isothermal measurements, the value is -1, while from the isobaric measurements a value of -0.25 is obtained.
Protein as the Mitochondrial Site for Action of Uncoupling Phenols
Authors: Weinbach Eugene C. , Garbus Joel
Published: October 2006

Phenolic reagents which uncouple oxidative phosphorylation are bound to the protein moiety of mitochondria. This interaction may induce configurational changes in the enzymes of oxidative phosphorylation, and these changes could be responsible for the uncoupling phenomenon.
Electroencephalograms of Sharks
Authors: Gilbert Perry W. , Hodgson Edward S. , Mathewson Robert F.
Published: October 2006

Patterns of electrical potentials recorded from the brains of sharks exhibit definite relationships to chemical and visual stimuli. Forebrain potentials reflect olfactory processes. Both restrained and free-swimming sharks exhibit mesencephalic responses to light and neural triggering of respiratory reflexes from the medulla. Early evolution of typical vertebrate brain functions, with emphasis upon chemoreception, is indicated.
Creative Scientists of Today
Authors: Chambers Jack A.
Published: October 2006

To investigate traits differentiating highly creative research scientists from less creative ones, a questionnaire was sent to 740 male scientists (400 chemists and 340 psychologists). Half of each group had achieved eminence as research scientists; the other half had not achieved research eminence, but were matched on relevant variables. Results indicated that creative scientists are more dominant than less creative ones, that they have more initiative, and are more strongly motivated toward intellectual success.
Production and Initial Characterization of Bionites: Materials Formed on a Bacterial Backbone
Authors: Mendelson Neil H.
Published: October 2006

The addition of soluble metal salts of calcium, iron, or copper to cultures of "
Bacillus subtilis
grown in web form nucleated precipitation at the surface of the bacterial cell walls. The mineralized cell filaments can be drawn into a fiber that when dried consists of a bacterial thread backbone carrying an inorganic solid. The ratios of organic to inorganic components (by weight) in the stiff brittle materials, called bionites, were: 1.08 for fe(2)bactonite, 1.8 for calbactonite, 2.3 for fe(3)bactonite, and 5 for cu(2)bactonite. X-ray photoelectron spectra suggest that the fe(3)bactonite contains Fe
2
O
3
, that calbactonite contains calcium carbonate, and that cu(2)bactonite contains CuCl (Cu I). Acid-base reactions of the bionites are compatible with these identifications. Burning out the organic phase of the febactonites yields a black magnetic material, presumably magnetite. The burnt cubactonite appears to yield elemental Cu(s). Calbactonite upon hydration was able to retain a genetically engineered enzymatic activity.
Nuclear Magnetic Resonance Spectroscopy in Superconducting Magnetic Fields
Authors: Nelson F. A. , Weaver H. E.
Published: October 2006

The first high-resolution nuclear magnetic resonance spectrometer operated at 30 Mcy/sec (7.05 kilogauss). The magnets constituted the only major obstacle to raising the frequency, but by continuous development over 10 years this frequency for proton resonance was increased to 100 Mcy/sec (23.4 kilogauss). Now, in one step, a system has been made to operate at twice this frequency and field intensity. It is not expected that superconducting magnets will generally replace iron magnets, but it is interesting to note that very few laboratories use the 30- and 40-Mcy/sec proton systems today.

Notwithstanding the cost and operating problems of the superconducting magnet system for the nuclear magnetic resonance spectrometer, the fact that this is the only practical means of developing both a stable and a high-intensity field puts it in a class by itself. For this reason, even though the maintenance of spectrometers with superconducting magnets requires rather specialized skills, this type of instrumentation will clearly have an important role in advancing scientific knowledge, by making possible analyses which have not been possible with presently available instruments.
5-Bromodeoxyuridine: Effect on Myogenesis in vitro
Authors: Stockdale F. , Okazaki K. , Nameroff M. , Holtzer H.
Published: October 2006

Presumptive myoblasts, obtained by treating muscle from 11-day chick embryos with trypsin, multiply in vitro. On the 4th or 5th day in culture they abruptly fuse, form long multinucleated myotubes, and begin to synthesize myosin. Cultured cells exposed to 5-bromodeoxyuridine incorporate this analog of thymidine into their DNA. Cells with such falsified DNA are reversibly inhibited from forming myotubes and synthesizing myosin; such cells, however, continue to synthesize the various species of molecules required for cell multiplication.
Biological Rhythms: A New Type in Strains of a Mutant of
Neurospora crassa
Authors: Neurath Peter W. , Berliner Martha D.
Published: October 2006

The formation of growth bands in
Neurospora
, with periods ranging from 15 to 90 hours, depends strongly on temperature and on composition of the growth medium, but not upon cycles of light and dark. The rhythm is endogenous but not "circadian."
Culturally Transmitted Patterns of Vocal Behavior in Sparrows
Authors: Marler Peter , Tamura Miwako
Published: October 2006

Male white-crowned sparrows have song "dialects," acquired in about the first 100 days of life by learning from older males. In the laboratory an alien white-crowned sparrow dialect can be taught. Once the song is established further acoustical experience does not change the pattern. White-crowned sparrows do not copy recorded songs of other sparrow species presented under similar conditions.
Spreading Depression and Recovery from Lateral Hypothalamic Damage
Authors: Teitelbaum Philip , Cytawa Jerzy
Published: October 2006

Spreading cortical depression reinstates aphagia and adipsia in rats recovered from lateral hypothalamic lesions. We suggest that cortical activity facilitates and maintains recovery by enhancing the activity of depressed, but intact, tissue adjacent to the lesions.
Charge-Transfer Self-Complex Formed by 8-Azaguanine
Authors: Macintyre Walter M.
Published: October 2006

The perpendicular distance between the planes of successive molecules of 8-azaguanine, in crystals of 8-azaguanine monohydrate, is 3.25 Å. This distance indicates intermolecular interaction of the charge-transfer type. 8-Azaguanine may act as a cell poison by forming a charge-transfer complex within the bacterial RNA.
Blood of a Cockroach: Unusual Cellular Behavior
Authors: Ritter Hope
Published: October 2006

In blood smears of a cockroach a small cell occurs which is frequently paired with a larger anucleate cytoplasmic body. The larger body in such pairs is free of nucleic acid, but contains polysaccharides, as demonstrated by the periodic acid-Schiff reaction. At one extreme of a series of these associations, the cell is completely distinct from the cytoplasmic body. At the other extreme the nucleus of the cell is within and apparently a part of the larger body. A graded series of pairs suggests a mechanism resembling phagocytosis in which the cytoplasmic body either gains or regains cell status by retaining the nucleus of the ingested member.
High-Pressure Transitions of Germanium and a New High-Pressure Form of Germanium
Authors: Bates Carl H. , Dachille Frank , Roy Rustum
Published: October 2006

Some transitions in germanium and other semiconductor systems have been detected after very long exposure to high pressures followed by various quenching techniques. In the case of Ge, a new high-pressure polymorph, Ge-IV, has been synthesized above 110 kilobars with a body-centered-cubic structure. The pressure for the Ge-I ⇄ Ge-III (body-centered-tetragonal structure) transition has been revised from about 120 to 25 kilobars at 30°C. The transition from the Ge-I (diamond structure) to the Ge-II (white tin structure) is metastable up to 140 kilobars. Thus some phase diagrams based on discontinuities observed in essentially dynamic systems may be inaccurate.
Bird Mortality after Spraying for Dutch Elm Disease with DDT
Authors: Wurster Charles F. , Wurster Doris H. , Strickland Walter N.
Published: October 2006

In Hanover, New Hampshire, where elms were sprayed with DDT, 151 dead birds were found; 10 dead birds were found in Norwich, Vermont, where no DDT was used. Chemical analyses of dead birds, observation of symptoms of DDT poisoning, and a population decline after spraying all indicate severe mortality among certain species in Hanover.
Clinoenstatite: High-Low Inversion
Authors: Perrotta A. J. , Stephenson D. A.
Published: October 2006

Clinoenstatite undergoes a metastable displacive inversion at 995°C. The new phase can be indexed (from x-ray powder pattern) on a triclinic cell with dimensions
a
= 10.00 Å;
b
=8.934 Å;
c
= 5.170 Å; alpha = 88.27°; beta = 70.03°; gamma = 91.09°. The new phase persists from 995° to 1010°C at the composition MgSiO
3
. For a solid solution (15 percent by weight) of diopside in clinoenstatite, the new phase persists from 995° to at least 1400°C and does not invert in periods of several hours to protoenstatite, the phase previously thought to be the stable form in this region.
Women in Science: Why So Few?
Authors: Rossi Alice S.
Published: October 2006

American society has prided itself on its concern for the fullest development of each individual's creative potential. As a nation, we have become sensitive to the social handicaps of race and class but have remained quite insensitive to those imposed because of sex. Those women who have entered the top professional fields have had to have extraordinary motivation, thick skins, exceptional ability, and some unusual pattern of socialization in order to reach their occupational destinations. In their backgrounds one is likely to find a professional mother, an unusually supportive father, or dedicated and stimulating teachers.
Hemoglobin and Oxygen: Affinities in Seven Species of Sciuridae
Authors: Hall F. G.
Published: October 2006

Studies of the respiratory function of the bloods of seven species of squirrels suggest that, in the evolution and adaptive radiation of this group, the oxygen affinity of hemoglobin has changed in a manner to better adapt the various species to different ways of life and different habitats. These changes are shown by the relative positions of the oxygen-dissociation curves of bloods of several species having dissimilar habits and environments.
Age, Personality, and Somatosensory Cerebral Evoked Responses
Authors: Shagass Charles , Schwartz Marvin
Published: October 2006

Cerebral responses to stimulation of the median nerve were recorded in 89 healthy subjects, aged 15 to 80 years. Relationships between response characteristics, age, sex, and Maudsley Personality Inventory variables were determined. Amplitudes increased significantly with age. Age interacted with "extraversion" so that more "extraverted" subjects under 20 and fewer "extraverted" subjects over 40 had larger responses.
Phase Relations in the System Na
2
Si
2
O
5
-SiO
2
Authors: Williamson J. , Glasser F. P.
Published: October 2006

A new compound, Na
6
Si
8
O
19
, is shown to be a thermodynamically stable phase in the Na
2
O-SiO
2
system at 1 atmosphere. The new compound melts incongruently to SiO
2
(quartz) and liquid at 808° ± 2°C, and it disproportionates to βNa
2
Si
2
O
5
and quartz at 700° ± 10°C.
Air Pollution Affects Pattern of Photosynthesis in
Parmelia sulcata
, a Corticolous Lichen
Authors: Pearson Lorentz , Skye Erik
Published: October 2006

Lichen disks kept in flasks contaminated with sulfur dioxide showed morphologic and photosynthetic abnormalities similar to those of lichens from an industrial center in Sweden, but lichens dried out for 4½ to 6 months in the laboratory showed neither. Thus some kinds of lichens may be absent from city environments because of atmospheric pollutants which destroy chlorophyll.
Detergents: Effects on the Chemical Senses of the Fish
Ictalurus natalis
(le Sueur)
Authors: Bardach John E. , Fujiya Masaru , Holl Arthur
Published: October 2006

Two types of detergents, one easily oxidized and the other not, damage the chemoreceptors of yellow bullheads,
Ictalurus natalis
(le Sueur) exposed to concentrations of 0.5 parts per million in the surrounding water. This concentration is considerably lower than that at which sublethal damage has been detected previously. Histological examination reveals erosion of the taste buds; electrophysiological methods and observations of swimming and feeding behavior reveal impairment of receptor function. Affected fish do not fully recover after 6 weeks in detergent-free water.
Transport of Sodium in Plant Tissue
Authors: Rains D. W. , Epstein Emanuel
Published: October 2006

Two mechanisms are implicated in the absorption of alkali cations by barley roots. Mechanism 1 has a high affinity for potassium, but its affinity for sodium is so low that, in the presence of even a low concentration of potassium (1 m
M
), sodium absorption by this mechanism is all but abolished. Mechanism 2 has a much lower affinity for alkali cations and is not highly selective; it transports sodium as well as potassium.
Crystal Multiplication without Nucleation
Authors: Chalmers Bruce , Williamson R. B.
Published: October 2006

Disk-shaped ice crystals grow out from the surface of polycrystalline ice in undercooled water. The rupture of the neck of the attached disk is a means of multiplying the number of viable crystals in the surrounding undercooled water. This is a source of frazil ice in streams and a source of new crystals in metal castings which are grain-refined by stirring.
Hypothalamic Motivational Processes as Reflected by their Hippocampal Electrical Correlates
Authors: Grastyán Endre , Karmos György , Vereczkey Lajos , Martin János , Kellenyi Lóránd
Published: October 2006

Electrical stimulation of the same hypothalamic point with current of mild or strong intensity produces opposite behavioral effects; moreover, interruption of either kind of stimulation invariably results in the appearance of powerful antagonistic aftereffects. There is a strict correlation between approach behavior and hippocampal theta rhythm on the one hand and withdrawal behavior and desynchronization on the other. The importance of the antagonistic aftereffects in the organization of conditional processes and in the interpretation of the "drive reduction" hypothesis is emphasized.
Growth of Mouse Mammary Glands in vivo after Monolayer Culture
Authors: Daniel Charles W. , DeOme K. B.
Published: October 2006

Mouse mammary tissue grown in primary cell culture did not display specialized characteristics of the parent tissue. When implanted into gland-free mammary fat pads, not only did some of these cultured cells grow and produce normal mammary outgrowths, but some of the outgrowths formed glands which displayed a variety of culture-induced abnormalities.
Aggressive Mimicry in
Photuris
: Firefly Femmes Fatales
Authors: Lloyd James E.
Published: October 2006

Firefly females of the genus
Photuris
, long known to be carnivorous, attract and devour males of the genus
Photinus
by mimicking the flash-responses of
Photinus
females. Although suspected, this behavior had not been observed previously.
Induction in vitro of Antibodies to Phage T2: Antigens in the RNA Extract Employed
Authors: Friedman H. P. , Stavitsky A. B. , Solomon J. M.
Published: October 2006

Cells from rat peritoneal exudate incubated in vitro with phage T2 yield RNA which induces cultures of rat lymph nodes to form antibodies. Complement fixation reveals T2 head, tail, and internal protein antigens in the RNA. Inoculating the RNA into mice that had previously been stimulated primarily with whole phage T2 results in a secondary response of neutralizing antibody.
Malignant Lymphomas Following Allogenic Disease: Transition from an Immunological to a Neoplastic Disorder
Authors: Schwartz Robert S. , Beldotti Lorraine
Published: October 2006

The graft versus host reaction which occurs in F
1
hybrid mice injected with parental spleen cells was used to examine several immunological theories of neoplasia. Long-term survivors of this reaction developed lymphoid neoplasms which resembled Hodgkin's disease and lymphosarcoma. Mice with these tumors were chimeras, but the parental cells present within their spleens had specific immunological tolerance toward host antigens. This, together with the finding that the tumors were transplantable only to isogenic recipients, indicates that the tumors were of host rather than donor origin.
Uranium Bioaccumulation by a
Citrobacter
sp. as a Result of Enzymically Mediated Growth of Polycrystalline HUO
2
PO
4
Authors: Macaskie Lynne E. , Empson Ruth M. , Cheetham Anthony K. , Grey Clare P. , Skarnulis A. Jerome
Published: October 2006

A
Citrobacter
sp. accumulates heavy deposits of metal phosphate, derived from an enzymically liberated phosphate ligand. The cells are not subject to saturation constraints and can accumulate several times their own weight of precipitated metal. This high capacity is attributable to biomineralization; uranyl phosphate accumulates as polycrystalline HUO
2
PO
4
at the cell surface. The precipitated metal is indistinguishable from crystalline HUO
2
PO
4
⋅4H
2
O grown by chemical methods.