bluuebunny/crossref_metadata_2025 huggingface dataset:
Visible Light from Semiconductors
Authors: Lorenz Max R.
Published: October 2006

Electroluminescence from semiconductor diode light sources can occur as a result of the application of a direct current at a low voltage to a suitably doped crystal containing a
p-n
junction. In recent years, it has become apparent that in some materials the efficiency of conversion of electric energy to visible light can be appreciably high. Since light-emitting diodes are compatible with the present electronic circuitry, they have many potential applications.
Chlorpromazine: Direct Measurement of Differential Behavioral Effect
Authors: Hollis John H.
Published: October 2006

A retarded child with a high stereotyped rocking rate was conditioned to pull a ball on a reinforcement schedule in which the fixed ratio of rewarded to nonrewarded responses was 100. Results show no rocking movements during ball-pulling; but when ball-pulling was on extinction, rocking returned to its original rate. Chlorpromazine blocked rocking movements during extinction, but had no effect on ball-pulling. Delivery of one free reinforcer was sufficient to reinstate ball-pulling after extinction, but the stimulus properties of the free reinforcer were not affected by the drug.
Voltage Noise in
Limulus
Visual Cells
Authors: Dodge F. A. , Knight B. W. , Toyoda J.
Published: October 2006

Intracellular recordings from
Limulus
eccentric cells suggest that the generator potential arises from the superposition of numerous discrete fluctuations in membrane conductance. If this is so, a relation between frequency response to flickering light and noise characteristics under steady light may be predicted. This prediction is verified experimentally. If a discrete fluctuation model is assumed, the data indicate that increased light has two major effects: (i) the discrete events are strongly light-adapted to smaller size, and (ii) the time course of each event becomes briefer.
Studies of Chlorophyll-Lipid-Water Systems
Authors: Chapman D. , Fast P. G.
Published: October 2006

Preliminary studies of the electronic absorption spectra of chlorophyll molecules in aqueous glycolipid and phospholipid dispersions are reported. The spectra show a shift for the red peak of chlorophyll of some 10 millimicrons to longer wavelength compared with the spectrum of chlorophyll in ether. Photochemical studies were carried out with cytochrome
c
incorporated into the aqueous layers separating the lipid bilayers.
Macrophage Spreading: Inhibition in Delayed Hypersensitivity
Authors: Fauve Robert M. , Dekaris Dragan
Published: October 2006

The capacity of peritoneal macrophages to spread was studied with cells of mice infected with
Listeria monocytogenes
and with cells of guinea pigs sensitized with BCG (bacille Calmette Guérin) vaccine or immunized with ovalbumin. In macrophages taken from animals having delayed hypersensitivity, this ability was markedly decreased by the presence of specific antigen for less than 1 hour. Such an effect was not observed in guinea pigs having only circulating antibodies.
Space-Filling Polyhedron: Its Relation to Aggregates of Soap Bubbles, Plant Cells, and Metal Crystallites
Authors: Williams Robert Edward
Published: October 2006

A fourteen-faced space-filling polyhedron which closely approximates the actual distribution of four-, five- and six-sided polygons found in packings of soap bubbles and biological cells is proposed as an alternative to the Kelvin tetrakaidecahedron as the ideal polyhedron for these packings. This polyhedron may also have relevance to crystallite morphologies and crystal structures.
Cytokinin from Soluble RNA of
Escherichia coli
: 6-(3-Methyl-2-butenylamino)-2-methylthio-9-β-D-ribofuranosylpurine
Authors: Burrows W. J. , Armstrong D. J. , Skoog F. , Hecht S. M. , Boyle J. T. A. , Leonard N. J. , Occolowitz J.
Published: October 2006

We have isolated a compound responsible for the cytokinin activity of soluble RNA from Escherichia coli. The structure, indicated as 6-(3-methyl-2-butenylamino)-2-methylthio-9-β-D-ribofuranosylpurine, C
16
H
23
N
5
O
4
S, on the basis of low- and high-resolution mass spectrometry, was established by unequivocal synthesis. The mass spectra, chromatographic behavior, and ultraviolet spectra of the compounds from natural and synthetic sources were identical.
Hypertrophic, Hypoactive Smooth Endoplasmic Reticulum: A Sensitive Indicator of Hepatotoxicity Exemplified by Dieldrin
Authors: Hutterer Ferenc , Schaffner Fenton , Klion Franklin M. , Popper Hans
Published: October 2006

Rats with hypertrophic smooth endoplasmic reticulum (ER) and increased activities of the drug-handling enzymes induced by dieldrin were stressed with larger doses of the pesticide. The activity of the drug-handling enzymes was thus reduced, but liver weight, smooth ER, and P-450 hemoprotein remained elevated. While no changes were apparent by light microscopy, the hypertrophic, hypoactive smooth ER was recognized as tight clusters of tubular membranes associated with abnormalities of the mitochondrial membrane. Similar but not identical morphologic changes were noted in human liver diseases associated with hepatic insufficiency. Hypertrophic, hypoactive smooth ER may indicate transition from adaptation of injury, and can be used as a sensitive parameter of toxicity.
Lysergic Acid Diethylamide: Mutagenic Effects in
Drosophila
Authors: Browning Luolin S.
Published: October 2006

d-Lysergic acid diethylamide causes a significant increase in recessive lethal mutations in the X chromosome of
Drosophila
males after intraperitoneal injection of massive doses.
Thiobases in
Escherichia coli
Transfer RNA: 2-Thiocytosine and 5-Methylaminomethyl-2-thiouracil
Authors: Carbon John , David Harold , Studier Martin H.
Published: October 2006

Two new sulfur-containing pyrimidine nucleotides have been isolated from hydrolyzates of
Escherichia coli
transfer RNA. The structures, 2-thiocytosine and 5-methylaminomethyl-2-thiouracil, have been assigned to the bases as a result of study of ultraviolet and mass spectra. An acid-degradation product, 5-methylaminomethyluracil, has been synthesized and is identical to that derived from the natural product.
Stage-Specific Adhesion of
Leishmania
Promastigotes to the Sandfly Midgut
Authors: Pimenta Paulo F. P. , Turco Salvatore J. , McConville Malcolm J. , Lawyer Phillip G. , Perkins Peter V. , Sacks David L.
Published: October 2006

Although leishmaniasis is transmitted to humans almost exclusively by the bite of infected phlebotomine sandflies, little is known about the molecules controlling the survival and development of
Leishmania
parasites in their insect vectors. Adhesion of
Leishmania
promastigotes to the midgut epithelial cells of the sandfly was found to be an inherent property of noninfective-stage promastigotes, which was lost during their transformation to metacyclic forms, thus permitting the selective release of infective-stage parasites for subsequent transmission by bite. Midgut attachment and release was found to be controlled by specific developmental modifications in terminally exposed saccharides on lipophosphoglycan, the major surface molecule on
Leishmania
promastigotes.
Deep-Ocean Basalts: Inert Gas Content and Uncertainties in Age Dating
Authors: Noble C. S. , Naughton J. J.
Published: October 2006

The radiogenic argon and helium contents of three basalts erupted into the deep ocean from an active volcano (Kilauea) have been measured. Ages calculated from these measurements increase with sample depth up to 22 million years for lavas deduced to be recent. Caution is urged in applying dates from deep-ocean basalts in studies on ocean-floor spreading.
Functional Asymmetry of the Human Brain
Authors: Cohen Bertram D. , Noblin Charles D. , Silverman Albert J. , Penick Syndor B.
Published: October 2006

Verbal and nonverbal memorization skills were tested before and after electroconvulsive shocks to the left, right, or both cerebral hemispheres of neurologically normal patients. As predicted, decrements for the left-hemisphere—shocked group were larger on the verbal than nonverbal tasks, while the reverse was true for the right-hemisphere—shocked group. Largest decrements on both tasks were shown by the bilaterally shocked group.
First Fossil Lamprey: A Record from the Pennsylvanian of Illinois
Authors: Bardack David , Zangerl Rainer
Published: October 2006

A fossil record of lampreys has previously been unknown. A new genus demonstrates the presence of this group in the Pennsylvanian. The body outline, parts of the head skeleton, rasping tongue mechanism, gill basket, and other internal organs are preserved. The fossils are very similar in structure to modern forms. The absence of hagfish characters in the fossil supports the view that the common ancestor of lampreys and hagfishes lived prior to the Pennsylvanian.
Deficiency of Reduced Nicotinamide-Adenine Dinucleotide Oxidase in Chronic Granulomatous Disease
Authors: Baehner Robert L. , Karnovsky Manfred L.
Published: October 2006

Reduced nicotinamide-adenine dinucleotide oxidase of normal human polymorphonuclear leukocytes has properties that would qualify it as the enzyme responsible for the respiratory burst during phagocytosis. The enzyme was deficient in leukocytes of five patients with chronic granulomatous disease. This lack of adequate reduced nicotinamide-adenine dinucleotide oxidase could be the basis for the metabolic abnormalities characteristic of these leukocytes and for their diminished bactericidal activity.
Human Monocytes: Distinct Receptor Sites for the Third Component of Complement and for Immunoglobulin G
Authors: Huber Heinz , Polley Margaret J. , Linscott William D. , Fudenberg H. Hugh , Müller-Eberhard Hans J.
Published: October 2006

Human monocytes contain two distinct receptor sites, one specific for the third component of complement (C′3), the other for immunoglobulin G (γG). The two receptors may function either independently or cooperatively in the induction of phagocytosis. Ingestion of erythrocytes coated with immunoglobulin M antibody requires a relatively large number of bound C′3 molecules per cell. Ingestion of erythrocytes sensitized with γG antibody is independent of complement; however, the reaction is inhibited by concentrations of γG far below those in normal serum. Inhibition by γG-globulin is overcome by a relatively small number of bound C′3 molecules per cell. The two monocyte receptors exert a cooperative effect on ingestion by monocytes of erythrocytes coated with γG antibody in the presence of inhibitory amounts of free γG.
Cucumber Sex Expression Modified by 2-Chloroethanephosphonic Acid
Authors: McMurray A. L. , Miller C. H.
Published: October 2006

Application of 2-chloroethanephosphonic acid (120 to 240 parts per million) to monoecious cucumber plants when the first true leaf was 2 centimeters in diameter has resulted in as many as 19 continuous pistillate nodes. Control of the flowering habit simplifies the production of hybrid seed and offers the possibility of enhancing cucumber yields.
Fatty Acid Biosynthesis Redirected to Medium Chains in Transgenic Oilseed Plants
Authors: Voelker Toni A. , Worrell Ann C. , Anderson Lana , Bleibaum Janice , Fan Calvin , Hawkins Deborah J. , Radke Sharon E. , Davies H. Maelor
Published: October 2006

Medium-chain fatty acids (FAs), found in storage lipids of certain plants, are an important renewable resource. Seeds of undomesticated California bay accumulate laurate (12:0), and a 12:0-acyl-carrier protein thioesterase (BTE) has been purified from this tissue. Sequencing of BTE enabled the cloning of a complementary DNA coding for a plastid-targeted preprotein. Expression of the complementary DNA in the seeds of
Arabidopsis thaliana
resulted in BTE activity, and medium chains accumulated at the expense of long-chain (≥16) FAs. Laurate became the most abundant FA species and was deposited in the storage triacylglycerols. These results demonstrate a mechanism for medium-chain FA synthesis in plants.
Interstellar Sulfur Hydride: A Search for the 111-Megahertz Lines
Authors: Meeks M. L. , Gordon M. A. , Litvak M. M.
Published: October 2006

Similarities in the energy-level structure of the sulfur hydride radical and the hydroxyl radical suggest that sulfur hydride in the interstellar medium might be detectable because of a population inversion or anti-inversion similar to that of the hydroxyl radical. We have searched for the 111.54-megahertz transition [
F
(total angular momentum quantum number) = 2 → 2] and for the 111.22-megahertz transition (
F
= 1 → 1) in the galactic radio source W49, one of the brightest hydroxyl emission sources. No sulfur hydride emission lines with half-power widths of 130 hertz or greater were detected with the 1000-foot Arecibo antenna. The upper limits established with 100-hertz filters were 50 and 60 flux units (1 flux unit= 10
26
watt meter
-2
hertz
-1
), respectively, for the two lines.
Fossil Mycelium with Clamp Connections from the Middle Pennsylvanian
Authors: Dennis Robert L.
Published: October 2006

A mycelium with clamp connections and chlamydospores has been discovered within the wood of a Middle Pennsylvanian fern. This suggests that forms extant in the middle of the Pennsylvanian had life cycles comparable to some modern Basidiomycetes.
Pulmonary Gas Transport Time: Larynx to Alveolus
Authors: Wagner W. W. , Latham L. P. , Brinkman P. D. , Filley G. F.
Published: October 2006

The transport time of gas from the larynx to pulmonary alveolar capillary blood was directly measured by injecting a bolus of carbon monoxide into the inspired airstream of dogs and photoelectrically monitoring the formation of carboxyhemoglobin in the capillaries on the surface of the lung. The rapidity of transit (0.3 second) implies that gas transport during inspiration is facilitated by an interaction between bulk flow and diffusion.
Thymus-Dependent Lymphocytes: Destruction by Lymphocytic Choriomeningitis Virus
Authors: Hanaoka Masao , Suzuki Shiro , Hotchin John
Published: October 2006

Selective destruction of small lymphocytes in the thymusdependent areas of lymph nodes and thymocytes was observed in mice infected with lymphocytic choriomeningitis virus. These changes were clearly evident in lymphoid and splenic tissue 3 days after infection and in the thymus by day 7. The destructive changes paralleled growth of the virus in these organs. The findings show that infection with lymphocytic choriomeningitis virus can temporarily cause the equivalent effect of neonatal thymectomy, that is, a "viral thymectomy," which appears to be related to the ability of this virus to cause persistent infection.
Bullfrog (
Rana catesbeiana
) Ventilation: How Does the Frog Breathe?
Authors: Gans Carl , de Jongh H. J. , Farber J.
Published: October 2006

Two short-term cyclic events, buccal oscillations and ventilatory cycles, occur in the bullfrog's respiration. During ventilation the frog fills the buccal cavity with air, then blows the pulmonary contents through the buccal cavity, and finally closes the nostrils while pumping the buccal contents into the lungs. The pulmonary efflux streams by the buccal contents with minimal mixing, and relatively pure air is pumped into the lungs. Buccal oscillations serve mainly to flush out the buccal cavity between ventilatory cycles.
Allantoinase: Association with Amphibian Hepatic Peroxisomes
Authors: Visentin Louis P. , Allen John M.
Published: October 2006

Differential and density-gradient centrifugation studies have established an association between allantoinase and peroxisomes from the liver of the frog
Rana pipiens
. The presence of allantoinase in the peroxisome indicates a uricolytic function for this organelle in the liver of amphibians.
Averaged Evoked Responses in Vigilance and Discrimination: A Reassessment
Authors: Ritter Walter , Vaughan Herbert G.
Published: October 2006

With the use of monopolar recordings for averaged evoked responses, detected signals in a vigilance task are associated with a late positive component which is absent for undetected signals as well as nonsignals. Bipolar recordings obscure the late positive component associated with detected signals. The data suggest that the late positive component represents cerebral processes associated with evaluation of unpredictable changes in stimulation.
Gene Dosage at the Lactate Dehydrogenase
b
Locus in Triploid and Diploid Teiid Lizards
Authors: Neaves William B. , Gerald Park S.
Published: October 2006

Triploid parthenogenetic lizards which are heterozygous at the lactate dehydrogenase
b
locus show approximately two doses of the
b
allele and approximately one dose of the
b
′ allele. This finding agrees with the triploid karyotype composed of two haploid complements of chromosomes indistinguishable from those of species carrying the
b
allele and one complement indistinguishable from that of the species which carries the
b
′ allele. Densitometry of electrophoretic patterns of lactate dehydrogenase from heart muscle and from kidney indicates approximately equal expression of each of the
b
alleles in the triploid lizards. Heterozygous diploid lizards from the same parthenogenetic species, in agreement with their karyotype, show equal doses of
b
and
b
′ alleles.
Preferential Synthesis of Ferritin and Albumin by Different Populations of Liver Polysomes
Authors: Hicks Sonja J. , Drysdale J. W. , Munro H. N.
Published: October 2006

Free polysomes and a mixture of free and membrane-attached polysomes were isolated separately from rat liver, and each was added to a cell-free, protein-synthesizing system. The free polysomes showed a greater capacity than the mixed polysome population for incorporation of
14
C-leucine into ferritin, whereas the reverse was true for
14
C-leucine incorporation into albumin.
Alcohol Dehydrogenase in Maize: Genetic Basis for Multiple Isozymes
Authors: Schwartz Drew
Published: October 2006

There are two distinct sets of alcohol dehydrogenase isozymes from maize, but they have subunits in common. Induced mutations at the (
Adh
1
) locus altered the migration rate of both Set I and Set II isozymes.
Precambrian Columnar Stromatolites in Australia: Morphological and Stratigraphic Analysis
Authors: Glaessner Martin F. , Preiss Wolfgang V. , Walter Malcolm R.
Published: October 2006

The stratigraphic distribution in Australian Precambrian rocks of columnar stromatolites, organosedimentary structures formed by blue-green algae, has been investigated. Their morphology is being studied according to methods developed in Russia. The discovery of successive different assemblages supports not only regional but also intercontinental stratigraphic correlations which are in agreement with available isotopic datings.
Prehistoric Investigations in Southeastern Turkey
Authors: Braidwood Robert J. , Çambel Halet , Watson Patty Jo
Published: October 2006

An archeological survey of the upper Tigris-Euphrates basin in Turkish Mesopotamia revealed a very early phase farming village and a nearby developed phase farming village. Late prehistoric developments in this region are critical to understanding of the beginnings of trade and metallurgy.
Orality, Preference Behavior, and Reinforcement Value of Nonfood Object in Monkeys with Orbital Frontal Lesions
Authors: Butter Charles M. , McDonald John A. , Snyder Daniel R.
Published: October 2006

Monkeys with orbital frontal ablation, compared with sham-operated controls, showed enhancement of oral tendencies toward nonfood items. Further, unlike the controls, they persistently performed an instrumental response for one of these nonfood items. On the other hand, the lesioned monkeys did not show altered preferences for food versus nonfood items. These findings suggest that reinforcement value and preferential ordering are dissociated by orbital frontal ablation.
Chromatin and Histones: Binding of Tritiated Actinomycin D to Heterochromatin in Mealy Bugs
Authors: Berlowitz Laurence , Pallotta Dominick , Sibley Carol H.
Published: October 2006

The degree of actinomycin D binding to DNA in chromatin is dependent upon the state of repression of chromatin. Living cells bind three times more tritiated actinomycin to euchromatin than to genetically inactive heterochromatin. Extraction of histone results in a general increase in tritiated actinomycin binding and in a ratio of the uptake in heterochromatin to that in euchromatin approaching unity.
Immune Adherence by the Fourth Component of Complement
Authors: Cooper Neil R.
Published: October 2006

An immune complex becomes reactive in immune adherence after the specific binding of the fourth component of complement (C4). Immune adherence produced by the fourth component of complement is indistinguishable from classical immune adherence in terms of all parameters tested, except that it is entirely independent of the participation of the second and third components of complement.
Clathrate Hydrates of Air in Antarctic Ice
Authors: Miller Stanley L.
Published: October 2006

Measurements of the dissociation pressure of nitrogen hydrate and oxygen hydrate show that the clathrate hydrate of air with the formula (N
2
,O
2
) ⋅ 6H
2
O should exist below about 800 meters in the Antarctic ice sheet. This accounts for the disappearance of gas bubbles at depths greater than 1200 meters. The hydrate should exist from this depth to the bottom of the core and should comprise 0.06 percent of the ice.
Oxygen-Hemoglobulin Dissociation Curves: Effect of Inherited Enzyme Defects of the Red Cell
Authors: Delivoria-Papadopoulos Maria , Oski Frank A. , Gottlieb Arlan J.
Published: October 2006

The blood of a patient with a deficiency of hexokinase in the red cells and a decreased concentration of 2,3-diphosphoglycerate in the red cells showed an increased affinity for oxygen, whereas a patient with a deficiency of pyruvate kinase and an elevated concentration of 2,3-diphosphoglycerate in the red cells had blood with a decreased affinity for oxygen. Defects in red cell glycolysis may alter the oxygen affinity of blood by virtue of their effect on 2,3-diphosphoglycerate concentrations in red cells.
Cell Cycle Regulation of Histone H1 Kinase Activity Associated with the Adenoviral Protein E1A
Authors: Giordano Antonio , Lee Joo Hun , Scheppler Judith A. , Herrmann Christine , Harlow Ed , Deuschle Ulrich , Beach David , Franza B. Robert
Published: October 2006

Several cellular proteins form stable complexes with the proteins encoded by the adenovirus early region 1A (E1A) gene in extracts derived from adenovirus infected or transformed cells. Two of the cellular proteins that bind to E1A have been identified; one, a 105-kilodalton protein (pRb), is the product of the retinoblastoma gene, and the other, a 60-kilodalton protein, is a human cyclin A. Two other proteins that bind E1A have now been shown to be related to p34
cdc2
. This E1A complex displayed histone H1-specific kinase activity; the kinase activity was modulated during the cell division cycle, and association of pRb with E1A apparently was not required for this activity.
Surface Areas of the Cerebral Cortex of Mammals Determined by Stereological Methods
Authors: Elias Hans , Schwartz David
Published: October 2006

The surface areas of the cerebral cortex excluding archipallium of 20 human, 11 cetacean, 6 carnivore, and 5 marsupial brains were determined by stereological methods. There exist rather strict relationships between volume, length of superficially exposed gyri, and cortical surface area.
Mariner 1969: Preliminary Results of the Infrared Radiometer Experiment
Authors: Neugebauer G. , Münch G. , Chase S. C. , Hatzenbeler H. , Miner E. , Schofield D.
Published: October 2006

The thermal energy emitted by Mars was measured in the 8- to 12- and 18- to 25-micrometer bands. The minimum temperature derived for the southern polar cap is 150°K, an indication that the cap is formed by frozen carbon dioxide. No significant temperature fluctuations were detected with a 100-kilometer scale.
Tropical Reef Corals: Tolerance of Low Temperatures on the North Carolina
Authors: Macintyre Ian G. , Pilkey Orrin H.
Published: October 2006

Individual heads of two species of reef or herinatypic coral,
Solenastrea hyades
(Dana) and
Siderastrea siderea
(Ellis and Solander), occur on rock outcrops on the inner continental shelf off North Carolina in waters where winter bottom temperatures are as low as 10.6°C. These temperatures are significantly lower than previously assumed minimum temperatures for the survival of tropical reef corals in their natural environment.
Sweat in Schizophrenic Patients: Identification of the Odorous Substance
Authors: Smith Kathleen , Thompson Geoffrey F. , Koster Harry D.
Published: October 2006

The substance causing the peculiar odor in sweat of schizophrenic patients has been isolated and identified as
trans
-3-methyl-2-hexenoic acid by gas chromatography, mass spectrometry, and nuclear magnetic resonance spectroscopy. The natural and the synthetic compounds were cleaved across the double bond to give 2-pentanone and oxalic acid, thereby confirming the structure.
Flower of
Tetraplasandra gymnocarpa
Hypogyny with Epigynous Ancestry
Authors: Eyde Richard H. , Tseng Charles C.
Published: October 2006

Comparative herbarium studies, floral anatomy, and distributional data show that
Tetraplasandra gymnocarpa
, an araliad with hypogynous flowers, evolved in Hawaii from ancestors with epigynous flowers. Suggested causes for this reversal of a well-known evolutionary trend are (i) isolation of the ancestors from flower-eating predators and (ii) selection for increased outcrossing.
Ontogeny of Adrenergic Arousal and Cholinergic Inhibitory Mechanisms in the Rat
Authors: Campbell Byron A. , Lytle Loy D. , Fibiger Hans C.
Published: October 2006

With spontaneous activity as a measure of arousal, dose response curves were established for scopolamine and amphetamine administered to 10-, 15-, 20-, 25-, and 100-day-old rats. Amphetamine always increased activity, but scopolamine had no effect on younger rats, which suggests that adrenergic excitatory areas in the brainstem mature more rapidly than cholinergic inhibitory areas in the forebrain.
Microtubular Protein: Synthesis and Metabolism in Developing Brain
Authors: Dutton Gray R. , Barondes Samuel
Published: October 2006

In the developing mouse brain 40 percent of the labeled soluble protein found after injection of leucine-C
14
consists of subunits with a molecular weight of 60,000 and with other characteristics of microtubular protein. This protein has a half-life of about 4 days.
Metastasizing Mammary Carcinomas in Rats: Induction and Study of Their Immunogenicity
Authors: Kim Untae
Published: October 2006

Widely metastasizing mammary adenocarcinomas were isolated from methylcholanthrene-fed inbred young adult female W/Fu rats that had been splenectomized or thymectomized, and from those that had been both splenectomized and thymectomized. These tumors are transplantable and maintain their metastasizing capacity. They are either nonimmunogenic or less immunogenic than the nonmetastasizing conventional methylcholathrene-induced mammary tumors, which are highly immunogenic.
Prevention of Metamorphosis by Exposure of Insect Eggs to Juvenile Hormone Analogs
Authors: Riddiford Lynn M.
Published: October 2006

Metamorphosis of the bugs
Pyrrhocoris apterus
and
Oncopeltus fasciatus
is blocked by the application of juvenile hormone analogs to the eggs 4 weeks earlier. One or more supernumerary larval molts occur to form "giant" larvae which routinely die without undergoing metamorphosis. When the corpora allata were excised at the outset of the fifth larval stage, the entire phenomenon vanished and all individuals underwent normal metamorphosis. The inhibition of metamorphosis can therefore be attributed to a continuation of the secretion of endogenous juvenile hormone by the corpora allata of mature larvae derived from eggs treated with juvenile hormone.
Photoperiodically Significant Photoreception in Sparrows: Is the Retina Involved?
Authors: Underwood Herbert , Menaker Michael
Published: October 2006

Blind house sparrows (150 birds) and normal ones (199 birds) were subjected to various photoperiodic treatments consisting of cycles of 12 hours light, 12 hours dark and 16 hours light, 8 hours dark at intensities ranging from 20 to 500 lux. The testicular, response of the blind birds was found to be indistinguishable from the response of normal birds under these conditions. The data show that a functional extraretinal photoreceptor exists in this species which is fully capable of mediating the gonadal response to photoperiodic stimuli.
Lunar Troilite: Crystallography
Authors: Evans Howard T.
Published: October 2006

Fine, euhedral crystals of troilite from lunar sample 10050 show a hexagonal habit consistent with the high-temperature NiAs-type structure. Complete three-dimensional counter intensity data have been measured and used to confirm and refine Bertaut's proposed low-temperature crystal structure.
Diffraction and Mössbauer Studies of Minerals from Lunar Soils and Rocks
Authors: Gay P. , Bancroft G. M. , Bown M. G.
Published: October 2006

Constituents of lunar soils and rocks were studied by powder and single-crystal x-ray diffraction. In addition to identification of minerals, including rare amphibole, mica, and aragonite, a detailed study of the important rock-forming minerals of the plagioclase, pyroxene, and olivine groups has begun. Mössbauer spectra were recorded from lunar soils, ground rock samples, and separates of iron-bearing minerals. The proportions of iron-bearing minerals were estimated from computer-fitted areas for the bulk samples. The Fe
2+
in the lower-density fraction of pyroxene was ordered, whereas that of the higher-density fraction was disordered.
High Crystallization Temperatures Indicated for Igneous Rocks from Tranquillity Base
Authors: Skinner Brian J.
Published: October 2006

Complex intergrowths of troilite (FeS) and iron in the igneous rocks from Tranquillity Base contain 8.4 percent native iron by volume. The intergrowths were derived from an initially homogeneous sulfide liquid that separated immiscibly from the magma at 1140°C or above. Textures show that the sulfide liquid formed late in the crystallization and cooling history of the igneous rocks and after the major ilmenite and pyroxene had formed.
Magnetic Resonance Studies of Lunar Samples
Authors: Manatt Stanley L. , Elleman Daniel D. , Vaughan Robert W. , Chan Sunney I. , Tsay Fun-Dow , Huntress Wesley T.
Published: October 2006

Electron spin resonance searches at 9.5 gigahertz on several fines samples and portions of several rocks have yielded signals whose lineshapes and temperature dependences show that the samples are principally ferromagnetic in nature. Proton magnetic resonance searches at 60 megahertz of these samples have not revealed any signals ascribable to water or any other types of hydrogen in concentrations greater than 0.0001 percent by weight contained in narrow lines (5 oersteds wide or less) and 0.01 percent by weight in wide lines (as wide as 100 oersteds).
Luminescence and Thermoluminescence Induced by Bombardment with Protons of 159 Million Electron Volts
Authors: Edgington J. A. , Blair I. M.
Published: October 2006

We have observed a red luminescence, qualitatively similar to that of enstatite achondrites, in unsorted fines, their separated mineral phases, and rock chips. The energy efficiency of the plagioclase fraction is approximately 1 percent. At -196°C the effect is enhanced by a factor between 1 and 2. All fractions except ilmenite exhibit blue thermoluminescence with a glow peak near -135°C and an energy efficiency ≈ 4 × 10
-6
. Unlike the thermoluminescence of terrestrial and meteoritic material, it is nonrepeatable even after annealing at 200°C. Similar thermoluminescence is seen in rock chips, but in unsorted fines it is masked by the opaque fractions.
Brain Norepinephrine: Enhanced Turnover after Rubidium Treatment
Authors: Stolk Jon M. , Nowack William J. , Barchas Jack D. , Platman Stanley R.
Published: October 2006

After biosynthesis of norepinephrine was inhibited, treatment of rats for 10 days with rubidium chloride (0.6 milliequivalent per kilogram of body weight) caused an increase in the rate of disappearance of norepinephrine in the brainstem but not in the telencephalon. Also the utilization of intracisternally injected tritiated norepinephrine was increased and was accompanied by a shift in the pattern of norepinephrine metabolism to normetanephrine. These data suggest that greater amounts of neuronally stored norepinephrine were released to central adrenergic receptors.
Production of Carbon Monoxide and Gaseous Hydrocarbons in Seawater: Relation to Dissolved Organic Carbon
Authors: Wilson D. F. , Swinnerton J. W. , Lamontagne R. A.
Published: October 2006

Carbon monoxide, ethylene, and propylene were produced in illuminated, cell-free distilled water or natural seawater systems to which dissolved organic matter produced by phytoplankton had been added. Methane and the higher saturated gaseous hydrocarbons were not produced. In the dark, little or no carbon monoxide and no hydrocarbons were produced in the distilled water systems; only carbon monoxide was produced in natural seawater, but less was produced than in the light.
Giant Radioactive Halos: Indicators of Unknown Radioactivity?
Authors: Gentry Robert V.
Published: October 2006

A new group of giant radioactive halos has been found with radii in excess of anything previously discovered. Since alternate explanations for these giant halos are inconclusive at present, the possibility is considered that they originate with unknown alpha radioactivity, either from isomers of known elements or from superheavy elements.
Transmissible Mink Encephalopathy: Experimental Transmission to the Squirrel Monkey
Authors: Eckroade Robert J. , Rhein Gabriele M. Zu , Marsh Richard F. , Hanson Robert P.
Published: October 2006

A progressive, fatal spongiform encephalopathy developed in three squirrel monkeys 11 months after inoculation with primate-passaged transmissible mink encephalopathy agent. The clinical symptoms and histopathologic and electron microscopic findings suggest that this naturally occurring disease of mink has been transmitted experimentally to squirrel monkeys.
Tumorigenesis in Mouse Skin: Inhibition by Synthetic Inhibitors of Proteases
Authors: Troll Walter , Klassen Arnold , Janoff Aaron
Published: October 2006

Three synthetic inhibitors of proteases (tosyl lysine chloromethyl ketone, tosyl phenylalanine chloromethyl ketone, and tosyl arginine methyl ester) inhibit the tumorigenesis initiated in mouse skin by 7,12-dimethylbenz(
a
)anthracene and promoted by croton oil or its active principle, phorbol ester. These protease inhibitors, when applied directly to mouse skin, inhibit some of the irritant effects of the tumor promoter and are not toxic.
Surface Films Compacted by Moving Water: Demarcation Lines Reveal Film Edges
Authors: McCutchen C. W.
Published: October 2006

When water flows under the edge of a surface film the large viscous shear stress at the edge prevents the film from spreading and raises a ridge on the water surface. Near the top of its downstream flank the ridge has an abrupt change in curvature that we see as a line on the water.
Black Sea: Recent Sedimentary History
Authors: Ross David A. , Degens Egon T. , MacIlvaine Joseph
Published: October 2006

Three distinct sedimentary units, which can be correlated throughout the basin, occur in cores collected from the Black Sea. Carbon-14 ages help to define the recent sedimentary history of the Black Sea.
Dimethylbenzanthracene Tumorigenesis and Aryl Hydrocarbon Hydroxylase in Mouse Skin: Inhibition by 7,8-Benzoflavone
Authors: Gelboin Harry V. , Wiebel Friedrich , Diamond Leila
Published: October 2006

Mouse skin contains aryl hydrocarbon hydroxylase which is highly inducible. The enzyme system is inhibited when 7,8-benzoflavone is added to homogenates of skin epidermis. 7,8-Benzoflavone also inhibits mouse skin tumorigenesis caused by repeated treatment with 9,10-dimethylbenzanthracene or by a single treatment with this chemical followed by weekly treatment with croton oil. These findings suggest that this enzyme system may be responsible for the activation of 9,10-dimethylbenzanthracene to its carcinogenic form.
Adenosine 3′,5′-Monophosphate in Rat Pineal Gland: Increase Induced by Light
Authors: Ebadi Manuchair S. , Weiss Benjamin , Costa Erminio
Published: October 2006

Rats were maintained in alternating periods of 12 hours of light and 12 hours of darkness. The concentration of adenosine 3′,5′-monophosphate in pineal gland was six times higher at the end of the light period than at the end of the period of darkness. This effect of light was abolished in blinded animals.
Extraretinal Light Perception: Entrainment of the Biological Clock Controlling Lizard Locomotor Activity
Authors: Underwood Herbert , Menaker Michael
Published: October 2006

The circadian activity rhythm of the iguanid lizard
Sceloporus olivaceus
can be entrained by light cycles whether or not the animals have eyes. Removal of the pineal organ and parietal eye in blinded lizards does not prevent entrainment. Our data demonstrate the existence of an extraretinal photoreceptor which can mediate entrainment of a biological clock in reptiles.
Blood Velocity Measurements in Intact Subjects
Authors: Morse O. C. , Singer J. R.
Published: October 2006

Venous blood velocities in intact human forearms can be measured by the use of nuclear magnetic resonance techniques. In essence, two separated coils are placed over the vein, and the arm is held in a magnetic field. Radio-frequency energy in one coil "flips" over the protons in the blood stream, and the second coil detects the arrival of the "flipped" protons. Human blood in vivo and in vitro has a nominal nuclear magnetic resonance relaxation time of 0.4 second.
Sex Pheromones of the Southern Armyworm Moth: Isolation, Identification, and Synthesis
Authors: Jacobson Martin , Redfern Robert E. , Jones William A. , Aldridge Mary H.
Published: October 2006

Two sex pheromones have been isolated from the female southern armyworm moth,
Prodenia eridania
(Cramer), and identified as
cis
-9-tetradecen-1-ol acetate, identical with the sex pheromone of the fall armyworm moth,
Spodoptera frugiperda
(J. E. Smith), and
cis
-9,
trans
-12-tetradecadien-1-ol acetate.
Radioreceptor Assay of Adrenocorticotropic Hormone: New Approach to Assay of Polypeptide Hormones in Plasma
Authors: Lefkowitz R. J. , Roth J. , Pastan I.
Published: October 2006

Biologically active iodine-125-labeled adrenocorticotropic hormone (ACTH) binds specifically to ACTH receptors extracted from adrenals. Unlabeled ACTH at 1 picogram per milliliter significantly displaces labeled ACTH from these receptors. This system, which appears to be applicable to all polypeptide hormones, provides a rapid and sensitive method for measurements of biologically active ACTH in dilute whole plasma.
Plasminogen: Purification from Human Plasma by Affinity Chromatography
Authors: Deutsch Dale G. , Mertz Edwin T.
Published: October 2006

Plasminogen was prepared from human plasma by affinity chromatography on L-lysine-substituted Sepharose. Thirty milligrams of plasminogen, with a specific activity of 100 caseinolytic units (Committee on Thrombolytic Agents) per milligram of nitrogen, were obtained from 340 milliliters of plasma. This corresponds to over 200-fold purification from plasma. Disc-gel electrophoresis at
p
H 8.3 indicated seven distinct bands, all of which contained activity.
A Thermophilic, Acidophilic Mycoplasma Isolated from a Coal Refuse Pile
Authors: Darland Gary , Brock Thomas D. , Samsonoff William , Conti S. F.
Published: October 2006

A thermophilic, acidophilic procaryote lacking a cell wall has been isolated from a coal refuse pile which had undergone self-heating. Electron micrographs, chemical assays for hexosamine, and the inability of vancomycin to inhibit growth confirm the lack of a cell wall. The apparent ability of the organism to reproduce by budding and the low guanine plus cytosine content of its DNA indicate a relation to the mycoplasmas. The temperature optimum of the organism is 59°C, and growth occurs over a range of 45° to 62°C. No growth occurs at 37°C or at 65°C. The optimum
p
H for growth is between 1 and 2, and growth occurs between
p
H 0.96 and 3.5 but does not occur at
p
H 0.35 and only poorly at
p
H 4.0. We propose to call this organism
Thermoplasma acidophila
. The existence of this organism extends considerably the range of habitats in which mycoplasma may occur.
"Polywater" and Sweat: Similarities between the Infrared Spectra
Authors: Rousseau D. L.
Published: October 2006

The infrared spectrum of "polywater" is remarkably similar to that of sodium lactate, the primary constituent of sweat. It is proposed, therefore, that this property of "polywater," and possibly others, results from accidental biological contamination. Such contamination is consistent with chemical analyses of "polywater" samples prepared both here and abroad.
Kinetics of Single-Layer Graphite Oxidation: Evaluation by Electron Microscopy
Authors: Evans E. L. , Griffiths R. J. M. , Thomas J. M.
Published: October 2006

Etch-decoration reveals that the rate of removal of carbon atoms exposed at monolayer steps on graphite surfaces is very different from the rate of removal, under identical conditions, at multilayer steps. At 1113°K and a pressure of 1.33 newtons per square meter of oxygen, the rate of oxidation (along the layer planes) is less by a factor of nearly 100 than that at multilayer steps.
Periodical Cicada: Sound Production and Hearing
Authors: Simmons James A. , Wever Ernest Glen , Pylka Joseph M.
Published: October 2006

The two main species intermingled in a brood of the 17-year cicada
(Magicicada)
have distinctive sound-making patterns and correspondingly different hearing abilities. Thus, they are acoustically isolated for mating purposes. Their simultaneous emergence and community "singing" has the important advantage of repelling predators.
The Last Interglacial: Paleotemperatures and Chronology
Authors: Emiliani C.
Published: October 2006

The O
18
/O
16
analysis and Th
230
/Pa
231
dating of deep-sea cores showed that the last interglacial age, with an early major temperature maximum followed by two smaller ones, extended from 100,000 to 70,000 years ago and was preceded by a glacial age extending from 120,000 to 100,000 years ago. The O
18
/O
16
analysis and Th
230
/U
234
dating of speleothems confirm and refine these ages.
Nest Predation Affecting the Breeding Season of the Clay-Colored Robin, a Tropical Song Bird
Authors: Morton Eugene S.
Published: October 2006

Predation seems more important than food availability in determining the reproductive period of the clay-colored robin
Turdus grayi
. It breeds in the dry season when food resources are low. The rainy season brings more food but breeding stops, possibly because of greatly increased nest predation.
Immunoglobulin M and Secretory Immunoglobulin A: Presence of a Common Polypeptide Chain Different from Light Chains
Authors: Mestecky Jiri , Zikan Jiri , Butler William T.
Published: October 2006

Unique polypeptide chains have been isolated from
S
-sulfonated light-chain fractions of human serum immunoglobulin M and colostral immunoglobulin A. Their electrophoretic mobilities, molecular weights, peptide maps, amino acid compositions, and antigenic determinants are very similar or perhaps identical but differ from those of light chains and secretory piece.
Disjunct Foliar Veins in Hawaiian
Euphorbias
Authors: Herbst Derral
Published: October 2006

Isolated segments of veins occur in the leaf mesophyll of several Hawaiian species of
Euphorbia
. These anomalous structures appear to consist entirely of tracheids and are a normal feature of the anatomy of species native to mesic and wet areas, but not to xeric, dry habitats.
Role of Nucleosomal Cores and Histone H1 in Regulation of Transcription by RNA Polymerase II
Authors: Laybourn Paul J. , Kadonaga James T.
Published: October 2006

The relation between chromatin structure and transcriptional activity was examined by in vitro transcription analysis of chromatin reconstituted in the absence or presence of histone H1. To maintain well-defined template DNA, purified components were used in the reconstitution of chromatin. Reconstitution of nucleosomal cores to an average density of 1 nucleosome per 200 base pairs of DNA resulted in a mild reduction of basal RNA polymerase II transcription to 25 to 50 percent of that obtained with naked DNA templates. This nucleosome-mediated repression was due to nucleosomal cores located at the RNA start site and could not be counteracted by the sequence-specific transcription activators Sp1 and GAL4-VP16. When H1 was incorporated into the chromatin at 0.5 to 1.0 molecule per nucleosome (200 base pairs of DNA), RNA synthesis was reduced to 1 to 4 percent of that observed with chromatin containing only nucleosomal cores, and this H1-mediated repression could be counteracted by the addition of Sp1 or GAL4-VP16 (antirepression). With naked DNA templates, transcription was increased by a factor of 3 and 8 by Sp1 and GAL4-VP-16, respectively (true activation). With H1-repressed chromatin templates, however, the magnitude of transcriptional activation mediated by Sp1 and GAL4-VP16 was 90 and more than 200 times higher, respectively, because of the combined effects of true activation and antirepression. The data provide direct biochemical evidence that support and clarify previously proposed models in which there is depletion or reconfiguration of nucleosomal cores and histone H1 at the promoter regions of active genes.
Red-Green Cone Interactions in the Increment-Threshold Spectral Sensitivity of Primates
Authors: Sperling H. G. , Harwerth R. S.
Published: October 2006

Threshold spectral sensitivity of primate eyes is the upper envelope of the sensitivity of three response channels. Sensitivity in the green and red channels is modeled as linear difference functions reflecting neural interaction between cones containing photopigments with 535- and 575-nanometer peaks. Sensitivity in the blue channel seems determined by a single class of cones containing a 445-nanometer photopigment.
Lateral Hypothalamus: Reevaluation of Function in Motivated Feeding Behavior
Authors: Devenport Lynn D. , Balagura Saul
Published: October 2006

In contrast to the existing views of lateral hypothalamic function, food motivated behavior appears to be greatly enhanced in animals that have recovered from lateral hypothalamic lesions. In a familiar environment, these rats begin eating 4.8 times sooner than normal controls, 5.6 times faster than hyperphagic rats that have received ventromedial hypothalamic lesions, and 4.7 times faster than animals with septal lesions. The same relation holds for latencies to eat in a novel environment and for rate of acquisition of a simple food-rewarded discrimination task. The concept of a lateral hypothalamic "hunger center" is questioned.
Cardiac Rate Regulated by Nutritional Factor in Young Rats
Authors: Hofer Myron A.
Published: October 2006

Milk fed by stomach tube to 2-week-old rats separated from their mothers without feeding for 16 hours transiently but fully reversed the decrease in cardiac rate which had occurred during separation. This effect was rapid in onset and was related to dosage; it was not dependent upon gastric distention, but did depend upon β-adrenergic transmission.
Monosodium Glutamate: Absence of Hypothalamic Lesions after Ingestion by Newborn Primates
Authors: Reynolds W. Ann , Lemkey-Johnston N. , Filer L. J. , Pitkin R. M.
Published: October 2006

After receiving monosodium glutamate by stomach tube, the brains of infant macaques were perfused for examination by light and electron microscopy. No morphological differences were observed in the hypothalamic regions of treated and control monkeys. However, inadequately fixed tissue had the same appearance as that of the previously reported brain lesion in a newborn monkey.