bluuebunny/crossref_metadata_2025 huggingface dataset:
Safety Concerns and Genetic Engineering in Agriculture
Authors: Brill Winston J.
Published: October 2006

Predictions about the safety of a recombinant plant or microorganism for agricultural use should be based on our vast experience with traditional practices, such as plant breeding and the use of microbial inoculants. An introduced plant, bacterium, or fungus containing foreign genes should be no greater environmental threat than such organisms without recombinant genes. Problems caused by introduction of organisms such as kudzu and the gypsy moth into a foreign environment do not imply problems for an organism, currently considered safe in its habitat, with characterized recombinant genes added to its genome.
Response Plasticity of Lateral Geniculate Neurons During and After Pairing of Auditory and Visual Stimuli
Authors: Chalupa Leo M. , Macadar Angelica W. , Lindsley Donald B.
Published: October 2006

Neurons of the lateral geniculate nucleus, responsive only to visual stimulation, show response plasticity during and after pairing of auditory and visual stimuli. Modal response histograms reveal a gradual decrement in the number of spikes at interstimulus pairing intervals of 0 and 100 milliseconds but not 500 milliseconds. This plasticity effect, limited to tonic units, may persist for 2 to 3 minutes after termination of click-flash pairing.
Myasthenia Gravis: Passive Transfer from Man to Mouse
Authors: Toyka Klaus V. , Brachman Daniel B. , Pestronk Alan , Kao Ing
Published: October 2006

Daily injections into mice of an ammonium sulfate-precipitated immunoglobulin fraction of serum from patients with myasthenia gravis were carried out for up to 14 days. The mice showed reduced amplitudes of miniature endplate potentials and reduced numbers of acetylcholine receptors at the neuromuscular junctions. Some mice showed typical decremental responses on repetitive nerve stimulation, with reversal by neostigmine. This represents the first evidence of a circulating factor in the serum of patients with myasthenia gravis which on passive transfer reproduces features of the disease in experimental animals.
Apneas During Sleep in Infants: Possible Relationship with Sudden Infant Death Syndrome
Authors: Guilleminault Christian , Peraita Rosa , Souquet Marianne , Dement William C.
Published: October 2006

Several types of apnea are described in premature infants and in infants who have survived breathing-stoppage episodes which may be related to the sudden infant death syndrome. Upper airway apnea appears to induce the greatest changes: oxygen desaturation is more pronounced than in a central apnea of similar duration, and secondary cardiac changes are observed earlier and are more severe.
Orientational Anisotropy in Infant Vision
Authors: Leehey Susan Cohen , Moskowitz-Cook Anne , Brill Sarah , Held Richard
Published: October 2006

Infants prefer to look at horizontal and vertical gratings rather than at oblique gratings only when they are at or near threshold spatial frequencies, as would be expected if acuity for oblique edges is lower than that for horizontal and vertical edges. That such a bias exists as early as 6 weeks of age suggests that the orientational asymmetry of the visual system depends on endogenous maturation rather than exposure to a carpentered world.
Stages in adolescent involvement in drug use
Authors: Kandel Denise
Published: October 2006

Two longitudinal surveys based on random samples of high school students in New York State indicate four stages in the sequence of involvement with drugs: beer or wine, or both; cigarettes or hard liquor; marihuana; and other illicit drugs. The legal drugs are necessary intermediates between nonuse and marihuana. Whereas 27 percent of high school students who smoke and drink progress to marihuana within a 5- to 6-month follow-up period, only 2 percent of those who have not used any legal substance do so. Marihuana, in turn, is a crucial step on the way to other illicit drugs. While 26 percent of marihuana users progress to LSD, amphetamines, or heroin, only 1 percent of nondrug marihuana users and 4 percent of legal drug users do so. This sequence is found in each of the 4 years in high school and in the year after graduation. The reverse sequence holds for regression in drug use.
Soluble Protein of the Organic Matrix of Mollusk Shells: A Potential Template for Shell Formation
Authors: Weiner Stephen , Hood Leroy
Published: October 2006

A significant proportion of the soluble protein of the organic matrix of mollusk shells is composed of a repeating sequence of aspartic acid separated by either glycine or serine. This regularly spaced, negatively charged aspartic acid may function as a template upon which mineralization occurs.
Current Status of Theories of Hearing
Authors: Békésy Georg v.
Published: October 2006

In summing up the current status of the hearing theories, it may be said that each of the vibration patterns of the basilar membrane postulated by the four major theories of hearing can be obtained by varying two elastic properties of the membrane—namely, the coupling between adjacent parts and the absolute value of the elasticity. If these two variables are adjusted to their numerical values in the cochlea of a living animal or a fresh preparation of the human ear, traveling waves are observed along the membrane. These traveling waves have a flat maximum that shifts its location along the membrane with a change of frequency—the place of the maximum determining the pitch. An enlarged dimensional model of the cochlea in which the nerve supply of the sensory organs on the basilar membrane was replaced by the skin of the arm indicates that the inhibitory action in the nervous system can produce quite sharp local sensations, which shift their place with changes in the frequency of the vibrations.
Stress-Induced Hyperphagia and Obesity in Rats: A Possible Model for Understanding Human Obesity
Authors: Rowland Neil E. , Antelman Seymour M.
Published: October 2006

Mild tail pinch administered to rats several times daily in the presence of sweetened milk induced immediate hyperphagia and led to considerable gain in body weight. Parallels are drawn with stress-induced hyperhagia and altered affective states in obese humans.
Intracellular Edema and Dehydration: Effects on Energy Metabolism in Alveolar Macrophages
Authors: Lewiston Norman J. , Theodore James , Robin Eugene D.
Published: October 2006

The effects of intracellular edema and dehydration on energy metabolism in alveolar macrophages were studied. Intracellular edema increased lactate production and reversibly decreased oxygen consumption. Dehydration caused no significant change in lactate production but irreversibly decreased oxygen consumption. These phenomena may be applicable to a wide variety of clinical problems including lung and brain edema.
Antagonism of Stimulation-Produced Analgesia by Naloxone, a Narcotic Antagonist
Authors: Akil Huda , Mayer David J. , Liebeskind John C.
Published: October 2006

Analgesia produced by focal electrical stimulation of the brain is partially reversed by the narcotic antagonist naloxone. The absence of complete reversal does not appear to be caused by inadequate doses of naloxone since doses higher than 1 milligram per kilogram of body weight did not increase the antagonism. It is suggested that stimulation-produced analgesia may result, at least in part, from release of an endogenous, narcotic-like substance, such as that recently reported by other investigators.
X-Ray Microscopy of Biological Objects with Carbon K
α
and with Synchrotron Radiation
Authors: Spiller E. , Feder R. , Topalian J. , Eastman D. , Gudat W. , Sayre D.
Published: October 2006

X-ray micrographs of biological objects have been obtained with a resolution better than 1000 angstroms by using poly(methyl methacrylate) x-ray resist and carbon K
α
or synchrotron radiation. Synchrotron radiation allows short exposure times; storage rings especially designed as radiation sources and improved x-ray resists would make exposure times under 1 second possible.
Stability and Properties of Double and Triple Helices: Dramatic Effects of RNA or DNA Backbone Composition
Authors: Roberts Richard W. , Crothers Donald M.
Published: October 2006

Studies of a series of short oligonucleotide double and triple helices containing either all RNA, all DNA, or a mixture of the two show strand-dependent variation in their stability and structure. The variation in stability for both groups falls over a range of greater than 10 kilocalories per mole. In forming the triple helix, RNA is favored on both pyrimidine strands, whereas DNA is favored on the purine strand. In general, relatively unstable duplexes form particularly stable triplexes and vice versa. Structural data indicate that the strands in hybrid helices adopt a conformation that is intermediate between molecules containing all DNA and all RNA. Thus, RNA-DNA hybrids were not forced into the conformation of the RNA (A-form). The provocative stability of the triplex with an RNA third strand+DNA duplex points to novel antisense strategies and opens the possibility of an in vivo role of these structures. Overall, the data emphasize the fundamental role of sugars in determining the properties of nucleic acid complexes.
Cyclic Stretching Stimulates Synthesis of Matrix Components by Arterial Smooth Muscle Cells in Vitro
Authors: Leung Donald Y. M. , Glagov Seymour , Mathews Martin B.
Published: October 2006

Rabbit aortic medial cells were grown on purified elastin membranes, which were then subjected to repeated elongation and relaxation or to agitation without stretching. Cells remained attached to the membranes, and cyclic stretching resulted in a two- to fourfold increase in rates of collagen, hyaluronate, and chondroitin 6-sulfate synthesis over those in agitated or stationary preparations. Synthesis of types I and III collagen was increased to the same degree. Stretching did not increase rates of chondroitin 4-sulfate or dermatan sulfate synthesis. Differences were not attributable to differences in cell number, for DNA synthetic rates were not increased by stretching. The model system devised to demonstrate these effects provides a means for relating various modes of mechanical stimulation to cell metabolism.
Origin and Migration of Oil
Authors: Baker E. G.
Published: October 2006

A relationship exists between the composition of crude oil and the solubility of the component hydrocarbons in dilute colloidal electrolyte solutions, suggesting that crude oil consists of hydrocarbons that were once solubilized in formation waters. It is not solubility in ordinary water or solubility in complete soap solution that correlates with the composition of oil but, rather, solubility in soap micelles. Because it implies a possible unloading mechanism, this concept is attractive, for it follows that when a soap solution is diluted with water, the soap micelles disperse and the hydrocarbons solubilized therein appear as discrete, filterable oil droplets.

Thus, it would seem that crude oil originates during the compaction of a sedimentary basin by virtue of the fact that sediment hydrocarbons dissolve in waters containing natural solubilizers and then come out of solution as oil droplets. The composition of crude oil as now understood is consistent with this hypothesis. And—most important—it is now possible to formulate meaningful questions, the answers to which, upon investigation in both field and laboratory, will go far toward enabling us to assess the validity of the mechanism presented here.

In addition to the implications regarding the composition of crude oil that are inherent in the hypothesis that crude oil collects from aqueous colloidal electrolyte solutions, there are several interesting implications from the geological viewpoint. To mention one, such a mechanism would lend credence to the suggestion that the source beds of petroleum are not necessarily unique accumulations of hydrocarbons in a limited area but, rather, may generally be coincident with the area from which water is expressed into the porous strata that eventually form the reservoirs.
Space Charge in Exhaust of Motor Vehicles
Authors: Brasefield C. J.
Published: October 2006

Exhaust gases are electrically charged, usually positively but sometimes negatively. This charge does not depend on the electric potential of the vehicle. Whether the charge is positive or negative seems to depend on whether water droplets or carbon particles predominate in the exhaust.
Carbon Dioxide Fixation in Marine Invertebrates: A Survey of Major Phyla
Authors: Hammen Carl S. , Osborne Paul J.
Published: October 2006

Fourteen species of marine invertebrates representing 12 phyla were kept in sea water containing NaHC
14
O
3
for 1 hour. All of them fixed CO
2
into acids of the Krebs citric acid cycle. In most species the major portion of the radioactivity recovered after chromatography was in succinic, fumaric, and malic acids. The findings favor the hypothesis that both CO
2
fixation and the citric acid cycle are virtually universal among marine invertebrates.
Critical Periods for the Effects of Infantile Experience on Adult Learning
Authors: Denenberg Victor H. , Bell Robert W.
Published: October 2006

Mice were shocked with 0.1, 0.3, or 0.5 ma of current at 2 to 3, 8 to 9, or 15 to 16 days. Handled, nonshocked and nonhandled controls were also used. In adulthood each group was split into thirds and taught an avoidance response under shock of 0.3, 0.5, or 0.7 ma. The amount of shock given during infancy and adulthood, and the age at which shock occurred, were all found to have significant effects upon learning.
Heterocaryotic Nature of Ring Formation in the Predaceous Fungus
Dactylella doedycoides
Authors: Feder William A. , Everard C. O. R. , Duddington C. L.
Published: October 2006

Morphologically indistinguishable conidia of the predaceous nematode-attacking hyphomycete
Dactylella doedycoides
Drechsler vary in their ability to produce constricting rings, depending upon their heterocaryotic state. Three types are noted: those producing rings with or without stimulation, those never producing rings, and a mixed or wild type, made up of a mixture of the first two types.
Tympanic Muscles and Control of Auditory Input during Arousal
Authors: Hugelin A. , Dumont S. , Paillas N.
Published: October 2006

A reticular stimulation producing a powerful arousal reaction decreases the potential in the cochlear nucleus evoked by a click. This reduction results from the contraction of the middle ear muscles, which lessens the pressure transmitted to the cochlea, and is not due to a direct neural inhibitory effect at the level of the first synapse of the auditory pathway.
Synchronous Division in
Chlamydomonas moewusii
Authors: Bernstein Emil
Published: October 2006

Mass cultures of
Chlamydomonas moewusii
have been synchronized by means of light-dark shifts. Division of at least 91 percent of the population was made to occur in 1/24 of the life cycle of the cells. The advantages of working with synchronized cultures of obligate autotrophs are discussed.
Effects of Absence of Saliva on Blood Feeding by Mosquitoes
Authors: Hudson Anne , Bowman L. , Orr C. W. M.
Published: October 2006

The salivary glands of
Aedes stimulans
(Walker) are the source of an antigen which produces typical bite reactions in men and laboratory rabbits. If the main salivary duct is cut, the reaction is not produced when the mosquito bites. Lack of saliva does not affect the intake or movement of blood into the mid-gut, nor does it prevent the development of eggs. The presence of an anesthetic component in saliva is suggested.
The
fms
-Like Tyrosine Kinase, a Receptor for Vascular Endothelial Growth Factor
Authors: de Vries Carlie , Escobedo Jaime A. , Ueno Hikaru , Houck Keith , Ferrara Napoleone , Williams Lewis T.
Published: October 2006

The
fms
-like tyrosine kinase (Flt) is a transmembrane receptor in the tyrosine kinase family. Expression of
flt
complementary DNA in COS cells conferred specific, high-affinity binding of vascular endothelial growth factor, also known as vascular permeability factor (VEGF-VPF), a factor that induces vascular permeability when injected in the guinea pig skin and stimulates endothelial cell proliferation. Expression of Flt in
Xenopus laevis
oocytes caused the oocytes to release calcium in response to VEGF-VPF. These findings show that
flt
encodes a receptor for VEGF-VPF.
Tumor Necrosis Factor-α Activates the Sphingomyelin Signal Transduction Pathway in a Cell-Free System
Authors: Dressler Kenneth A. , Mathias Shalini , Kolesnick Richard N.
Published: October 2006

The mechanism of tumor necrosis factor (TNF)-α signaling is unknown. TNF-α signaling may involve sphingomyelin hydrolysis to ceramide by a sphingomyelinase and stimulation of a ceramide-activated protein kinase. In a cell-free system, TNF-α induced a rapid reduction in membrane sphingomyelin content and a quantitative elevation in ceramide concentrations. Ceramide-activated protein kinase activity also increased. Kinase activation was mimicked by addition of sphingomyelinase but not by phospholipases A
2
, C, or D. Reconstitution of this cascade in a cell-free system demonstrates tight coupling to the receptor, suggesting this is a signal transduction pathway for TNF-α.
Molecular Localization of an Ion-Binding Site Within the Pore of Mammalian Sodium Channels
Authors: Backx Peter H. , Yue David T. , Lawrence John H. , Marban Eduardo , Tomaselli Gordon F.
Published: October 2006

Sodium channels are the major proteins that underlie excitability in nerve, heart, and skeletal muscle. Chemical reaction rate theory was used to analyze the blockage of single wild-type and mutant sodium channels by cadmium ions. The affinity of cadmium for the native tetrodotoxin (TTX)-resistant cardiac channel was much higher than its affinity for the TTX-sensitive skeletal muscle isoform of the channel (μl). Mutation of Tyr
401
to Cys, the corresponding residue in the cardiac sequence, rendered μl highly susceptible to cadmium blockage but resistant to TTX. The binding site was localized approximately 20% of the distance down the electrical field, thus defining the position of a critical residue within the sodium channel pore.
Functional Modulation of GABA
A
Receptors by cAMP-Dependent Protein Phosphorylation
Authors: Moss Stephen J. , Smart Trevor G. , Blackstone Craig D. , Huganir Richard L.
Published: October 2006

γ-Aminobutyric acidA (GABA
A
) receptors are ligand-gated ion channels that mediate inhibitory synaptic transmission in the central nervous system. The role of protein phosphorylation in the modulation of GABA
A
receptor function was examined with cells transiently transfected with GABA
A
receptor subunits. GABA
A
receptors consisting of the α
1
and β
1
or the α
1
, β
1
, and γ
2
subunits were directly phosphorylated on the β
1
subunit by adenosine 3′,5′-monophosphate (cAMP)-dependent protein kinase (PKA). The phosphorylation decreased the amplitude of the GABA response of both receptor types and the extent of rapid desensitization of the GABA
A
receptor that consisted of the α
1
and β
1
subunits. Site-specific mutagenesis of the serine residue phosphorylated by PKA completely eliminated the PKA phosphorylation and modulation of the GABA
A
receptor. In primary embryonic rat neuronal cell cultures, a similar regulation of GABA
A
receptors by PKA was observed. These results demonstrate that the GABA
A
receptor is directly modulated by protein phosphorylation and suggest that neurotransmitters or neuropeptides that regulate intracellular cAMP levels may modulate the responses of neurons to GABA and consequently have profound effects on synaptic excitability.
Biosynthesis of Human Papillomavirus from a Continuous Cell Line Upon Epithelial Differentiation
Authors: Meyers Craig , Frattini Mark G. , Hudson John B. , Laimins Laimonis A.
Published: October 2006

The study of the human pathogen papillomaviruses (HPVs) has been hampered by the inability to propagate the virus in tissue culture. The addition of 12-
O
-tetradecanoyl phorbol-13-acetate to the media of organotypic (raft) cultures increased expression of physiological markers of keratinocyte differentiation and concomitantly induced production of virions. Capsid production was detected in differentiated suprabasal cells. Virions approximately 54 nanometers in size were observed by electron microscopy in raft tissue cross sections in the suprabasal layers. Virions purified through isopycnic gradients were found to contain type 31b DNA and exhibited an icosahedral shape similar to that of papillomaviruses found in clinical samples.
Punishment in the Squirrel Monkey
Saimiri sciurea
Authors: Appel James B.
Published: October 2006

Punishment has been found not only to suppress the rate of a food-maintained operant response in the squirrel monkey under conditions of high deprivation but to inhibit the emission of that response for 50 days (400 hours) after the punishment has been withdrawn.
A "D"-like Antigen in Rhesus Red Blood Cells and in Rh-Positive and Rh-Negative Red Cells
Authors: Levine Philip , Celano Marino , Fenichel Richard , Singher Heron
Published: October 2006

A "D"-like antigen has been demonstrated in human and rhesus red cells. These red cells, as well as heat extracts of human blood (Rh-positive or Rh-negative), induce formation of "D"-like antibodies in guinea pigs. These antibodies, when exposed to rhesus red cells or to Rh-positive or Rh-negative red cells, yield eluates of "D"-like specificity.
"Bioconvection Patterns" in Cultures of Free-Swimming Organisms
Authors: Platt John R.
Published: October 2006

The moving polygonal patterns in dense cultures of
Tetrahymena
and other ciliates and flagellates look like "Benard cells," but are not due to thermal convection. They seem to be due to a similar dynamic instability that occurs when the energy input is internal and mechanical. The high concentration in the patterns may be useful in fertilization.
Formation of Diamond by Explosive Shock
Authors: DeCarli Paul S. , Jamieson John C.
Published: October 2006

Samples of graphite have been recovered after exposure to explosive shocks of 300,000-atm estimated intensity. X-ray and electron-diffraction examinations prove the existence of diamond in this material. The mechanism proposed for the formation of diamond under these conditions is simple compression in the
c
-axis direction of the rhombohedral form of graphite.
First-Year Breakdown of Leaf Litter in Southern Appalachian Forests
Authors: Shanks R. E. , Olson J. S.
Published: October 2006

Breakdown of organic matter, an important step in the ecological circulation of chemical elements, was measured in Great Smoky Mountain and Oak Ridge forests. Greatest variation in first-year weight loss of leaves in nylon net bags was due to species (
Fagus grandifolia
21 percent,
Acer saccharum
32 percent,
Quercus shumardii
34 percent,
Quercus alba
39 percent,
Morus rubra
64 percent). At elevations of 5200, 3400, and 850 ft, losses for all five species averaged, respectively, 29, 34, and 40 percent for leaves placed in spruce, hemlock, and pine stands, and 35, 40, and 46 percent for leaves placed in beech, cove hardwood, and whiteoak stands.
Acquired Tolerance of Leaves to Heat
Authors: Yarwood C. E.
Published: October 2006

When bean, cowpea, cucumber, fig and tobacco leaves were heated 15 to 30 seconds at 50°C, 12 to 48 hours later they tolerated a temperature of 55°C up to three times as long for the same degree of heat injury as did leaves which were not previously heated.
Colonial Growth of
Neurospora
Authors: de Terra Noël , Tatum E. L.
Published: October 2006

L-Sorbose, an agent which induces colonial growth in
Neurospora crassa
, also induces structural changes in the cell wall. Acid hydrolyzates of cell walls isolated from sorbose-grown (colonial) hyphae contain more glucosamine and less glucose than do hydrolyzates of cell walls obtained from normally growing hyphae. Snail digestive juice, an agent which effects a structural change in the cell wall of
N. crassa
by liberating from it large quantities of glucose, has been found to induce colonial growth.
New Method for Heart Studies
Authors: Holter Norman J.
Published: October 2006

I have proposed that orthodox electrocardiography be implemented, both for research and medical purposes, by the use of long-period, continuous recording of heart potentials with a portable, self-contained instrument—the electrocardiocorder together with semiautomatic methods for the rapid analysis of the resulting voluminous data. An electronic system to make this concept practical has been developed in our laboratory and typical results are described in this article.
Modulation of Activity of the Promoter of the Human
MDR
1 Gene by Ras and p53
Authors: Chin Khew-Voon , Ueda Kazumitsu , Pastan Ira , Gottesman Michael M.
Published: October 2006

Drug resistance in human cancer is associated with overexpression of the multidrug resistance (
MDR
1) gene, which confers cross-resistance to hydrophobic natural product cytotoxic drugs. Expression of the
MDR
1 gene can occur de novo in human cancers in the absence of drug treatment. The promoter of the human
MDR
1 gene was shown to be a target for the c-Ha-Ras-1 oncogene and the p53 tumor suppressor gene products, both of which are associated with tumor progression. The stimulatory effect of c-Ha-Ras-1 was not specific for the
MDR
1 promoter alone, whereas a mutant p53 specifically stimulated the
MDR
1 promoter and wild-type p53 exerted specific repression. These results imply that the
MDR
1 gene could be activated during tumor progression associated with mutations in Ras and p53.
Toxicity of Plankton to Cristispira Inhabiting the Crystalline Style of a Mollusk
Authors: Berkeley C.
Published: October 2006

The crystalline style of
Saxidomus giganteus
supports a large population of
Cristispira
spp. which swim freely in it except near the functional end which impinges on the gastric shield. Here the style is frayed and mixed with ground food material, while amylolytic enzymes and an oxidase are released. Glucosone appears to result from oxidase activity. This proved toxic to cristispira in fairly high dilution. Several tests of the toxicity of extracts of plankton, which forms the food of
Saxidomus,
were made. In every case such extracts proved toxic.
Are New Neurons Formed in the Brains of Adult Mammals?
Authors: Altman Joseph
Published: October 2006

In an autoradiographic investigation, the production of brain lesions in rats was combined with intracranial injection of thymidine-H
3
. Nuclei of numerous glia cells were found labeled in brain regions associated with the traumatized areas. In addition, some neurons and neuroblasts showed labeling, suggesting the possibility of proliferation of neurons in adult rats.
Calcium Channels Coupled to Glutamate Release Identified by ω-Aga-IVA
Authors: Turner Timothy J. , Adams Michael E. , Dunlap Kathleen
Published: October 2006

Presynaptic calcium channels are crucial elements of neuronal excitation-secretion coupling. In mammalian brain, they have been difficult to characterize because most presynaptic terminals are too small to probe with electrodes, and available pharmacological tools such as dihydropyridines and ω-conotoxin are largely ineffective. Subsecond measurements of synaptosomal glutamate release have now been used to assess presynaptic calcium channel activity in order to study the action of peptide toxins from the venom of the funnel web spider
Agelenopsis aperta
, which is known to inhibit dihydropyridine and ω-conotoxin-resistant neuronal calcium currents. A presynaptic calcium channel important in glutamate release is shown to be ω-Aga-IVA sensitive and ω-conotoxin resistant.
Observations on the Solubility of Skeletal Carbonates in Aqueous Solutions
Authors: Chave K. E. , Deffeyes K. S. , Weyl P. K. , Garrels R. M. , Thompson M. E.
Published: October 2006

Carbonate skeletal materials of marine organisms exhibit a wide range of solubilities in aqueous solutions. In most cases, the dissolution of the carbonate mineral is irreversible and therefore the material can have no true equilibrium solubility. Relative solubilities have been measured in distilled water and in sea water. The least soluble mineral appears to be calcite with low magnesium content; the most soluble is calcite containing 20 to 30 percent MgCO
3
in solid solution. Aragonite has an intermediate solubility.
Archeological Survey and Excavation in Iran, 1961
Authors: Hole Frank
Published: October 2006

Recent surface survey for prehistoric archeological sites in western Iran has contributed toward defining three centers of early agricultural village settlement. Excavation at a site in upper Khuzistan revealed a sequence of settled life which, at its earliest, may antedate food production. The site also yielded faunal evidence for an ecological change subsequent to the end of the Pleistocene.
Visual Depth Perception of a 10-Month-Old Monocular Human Infant
Authors: Walk Richard D. , Dodge Sue H.
Published: October 2006

A monocular infant tested on the "visual cliff" crawled over glass which had a patterned surface just beneath it and would not cross glass which had the same pattern 40 inches below its surface. Since this infant, using only monocular visual cues, was able to discriminate depth, the experiment disproves a general belief in the primacy of binocular cues in depth perception.
Nature of the Sound Produced by
Drosophila melanogaster
during Courtship
Authors: Shorey H. H.
Published: October 2006

The wing vibrations of courting male
Drosophila melanogaster
Meigen produced pulsations of sound, with each pulse apparently caused by 1 to 2 cycles of wing movement. The average repetition rate at 25°C was 29.8 pulses per second. The rate was dependent on temperature, increasing at 1.4 pulses per additional degree Celsius.
CD19: Lowering the Threshold for Antigen Receptor Stimulation of B Lymphocytes
Authors: Carter Robert H. , Fearon Douglas T.
Published: October 2006

Lymphocytes must proliferate and differentiate in response to low concentrations of a vast array of antigens. The requirements of broad specificity and sensitivity conflict because the former is met by low-affinity antigen receptors, which precludes achieving the latter with high-affinity receptors. Coligation of the membrane protein CD19 with the antigen receptor of B lymphocytes decreased the threshold for antigen receptor-dependent stimulation by two orders of magnitude. B lymphocytes proliferated when approximately 100 antigen receptors per cell, 0.03 percent of the total, were coligated with CD19. The B cell resolves its dilemma by having an accessory protein that enables activation when few antigen receptors are occupied.
Cloning and Characterization of Inducible Nitric Oxide Synthase from Mouse Macrophages
Authors: Xie Qiao-wen , Cho Hearn J. , Calaycay Jimmy , Mumford Richard A. , Swiderek Kristine M. , Lee Terry D. , Ding Aihao , Troso Tiffany , Nathan Carl
Published: October 2006

Nitric oxide (NO) conveys a variety of messages between cells, including signals for vasorelaxation, neurotransmission, and cytotoxicity. In some endothelial cells and neurons, a constitutive NO synthase is activated transiently by agonists that elevate intracellular calcium concentrations and promote the binding of calmodulin. In contrast, in macrophages, NO synthase activity appears slowly after exposure of the cells to cytokines and bacterial products, is sustained, and functions independently of calcium and calmodulin. A monospecific antibody was used to clone complementary DNA that encoded two isoforms of NO synthase from immunologically activated mouse macrophages. Liquid chromatography-mass spectrometry was used to confirm most of the amino acid sequence. Macrophage NO synthase differs extensively from cerebellar NO synthase. The macrophage enzyme is immunologically induced at the transcriptional level and closely resembles the enzyme in cytokine-treated tumor cells and inflammatory neutrophils.
Inhibition of Neutrophil Chemokinesis on Vitronectin by Inhibitors of Calcineurin
Authors: Hendey Bill , Klee Claude B. , Maxfield Frederick R.
Published: October 2006

Migration of human polymorphonuclear neutrophils on vitronectin is dependent on repeated transient increases in the concentration of intracellular free calcium ([Ca
2+
]
i
). A specific peptide inhibitor of the Ca
2+
-calmodulin-dependent phosphatase calcineurin was introduced into the cytoplasm of neutrophils. The peptide inhibited neutrophil migration on vitronectin by interfering with the release of the cells from sites of attachment. A similar reduction in motility on vitronectin occurred when cells were treated with the immunosuppressant FK506, which also inhibits calcineurin when bound to its binding protein, FKBP. These results indicate that a rise in [Ca
2+
]
i
reduces integrin-mediated adhesion to vitronectin by a mechanism that requires calcineurin activity.
Citrus Flavonoid Complex: Chemical Fractionation and Biological Activity
Authors: Freedman Louis , Merritt A. Jay
Published: October 2006

A study was made of the anti-inflammatory activity of the fractionated components of a citrus flavonoid complex. Several highly active components, distinct from hesperidin and naringin, were isolated and tested for anti-inflammatory activity. A method for evaluation of this biological activity is recommended.
Pliocene-Pleistocene Boundary in Deep-Sea Sediments
Authors: Ericson David B. , Ewing Maurice , Wollin Goesta
Published: October 2006

For a hundred years students of the Pleistocene have looked for evidence of the climatic change which initiated the Pleistocene epoch. Glacial deposits on the continents have been of little help because of their discontinuity and because of the destructive effect of later glaciations. Hence, Pleistocene geologists have turned to the uplifted Pliocene-Pleistocene marine sediments of the Mediterranean region. In the absence of evidence of a single, clearly defined climatic change in this sedimentary section, they have agreed to define the beginning of the Pleistocene by the first appearance of
Anomalina baltica
, a species of benthic Foraminifera tolerant of cool water. This definition leaves much to be desired: It rests on a single benthic species whose areal distribution must have been partly determined by local conditions on the sea floor; it is useless outside of the Mediterranean region; and there is no convincing evidence that the first appearance of
Anomalina baltica
in the Mediterranean coincided with the onset of the first glaciation.
Somatic Instability Caused by a Cysteine-Sensitive Gene in
Arabidopsis
Authors: Rédei G. P.
Published: October 2006

A recessive gene immutans (
im
) is responsible for abnormal chloroplast development which results in variegation in
Arabidopsis
plants. Somatic mutability is simulated, though only functional disorder is involved. Cysteine and low temperature favor normal function, while homocysteine interferes with chloroplast development without producing an adverse effect on the growth of the mutant.
Disappearance of Luminous Designs
Authors: McKinney John Paul
Published: October 2006

When a subject fixates on a luminous design under conditions of low illumination, he experiences a fragmenting disappearance of the figure. This fragmentation occurs in meaningful units and is comparable to the disappearance of images stabilized on the retina. The luminous paint technique offers a new and simple approach to the study of visual perception.
Antarctic Micrometazoa: Fresh-Water Species in the McMurdo Sound Area
Authors: Dougherty Ellsworth C. , Harris Larry G.
Published: October 2006

The multicellular microfauna in fresh-water bodies of Ross Island and the nearby continental coast of Victoria Land is strikingly impoverished with respect to major groups. Yet there are thriving populations belonging to the Rotifera, Nematoda, Tardigrada, and Turbellaria.
Communication of Science Information
Authors: Tannenbaum Percy H.
Published: October 2006

There are obvious limitations to normative studies of the kind described. Many of the studies dealt with special content areas—for example, mental health—and thus may not provide a sound basis for generalization. Selection of the various samples presented still greater problems. In some cases, the universe was so ill-defined (for example, that of science writers) that conventional sampling procedures were of doubtful significance. There were also limitations of subject availability and funds. Thus, we tended to proceed on an ad hoc basis, using more-or-less intact groups where we could find them—a group of scientists or a group of science writers attending an NSF-sponsored seminar; news editors from papers in the State of Wisconsin; and so on.
Algal Virus: Isolation
Authors: Safferman Robert S. , Morris Mary-Ellen
Published: October 2006

Freshwater blue-green algae of the genera
Lyngbya
,
Plectonema
, and
Phormidium
are susceptible to a virus recently isolated from a waste-stabilization pond. Electron micrographs of a partially purified preparation show that the viral particle has an icosahedral structure about 66 mμ in diameter.
Psychological Implications of Word Usage
Authors: Nunnally Jum C. , Flaugher Ronald L.
Published: October 2006

We do not mean to imply that research on individual differences in word usage is easy or that investigations typically meet with success. Many studies have failed, either because no reliable categories of words were found or, if such categories were found, because no significant correlations were obtained with other forms of behavior. Only the naïve would expect to find more than rather small correlations between individual differences in learning, perception, and social behavior and differences in word usage. Human behavior is so complexly determined that it is illogical to expect various kinds of individual differences to correlate highly. In order to document such small correlations it is necessary to work with relatively large samples of subjects. Usually 300 subjects or more are required for a study.
Haploids: High-Frequency Production from Single-Embryo Seeds in a Line of Pima Cotton
Authors: Turcotte E. L. , Feaster Carl V.
Published: October 2006

Progenies of a doubled haploid from Pima S-1, a commercial variety of
Gossypium barbadense
L., contained a very high frequency of haploid plants. The haploid plants, in contrast with those previously reported in cotton, originated from single- rather than twin-embryo seeds. Apparently the haploid-producing ability of this line of cotton is inherited.
High-Pressure Synthesis of Molybdates with the Wolframite Structure
Authors: Young A. P. , Schwartz C. M.
Published: October 2006

A series of small cation molybdates, MgMoO
4
, MnMoO
4
, FeMoO
4
, CoMoO
4
, NiMoO
4
, and ZnMoO
4
with the wolframite structure characteristic of the corresponding tungstates have been synthesized at high pressure and temperature. The high-pressure compounds revert to the ambient pressure modifications if heated in air at 600°C.
Teratogenic Effects of Meclizine Hydrochloride on the Rat
Authors: King C. T. G.
Published: October 2006

Congenital malformations were induced in the offspring of pregnant Sprague-Dawley rats by the administration of relatively large doses of meclizine hydrochloride (Bonine). The critical period of gestation for administration was from the 12th to 15th day. Anomalies were produced in the tongue, palatal closure, mouth, lower jaw, vertebrae and limbs.
Some Anthropological Aspects of the Prehistoric Tyrolean Ice Man
Authors: Seidler Horst , Bernhard Wolfram , Teschler-Nicola Maria , Platzer Werner , zur Nedden Dieter , Henn Rainer , Oberhauser Andreas , Sjøvold Thorstein
Published: October 2006

The corpse of a Late Neolithic individual found in a glacier in Oetztal is unusual because of the intact nature of all body parts that resulted from the characteristics of its mummification process and its protected geographical position with regard to glacier flow. Anthropological data indicate that the man was 25 to 40 years old, was between 156 and 160 centimeters in stature, had a cranial capacity of between 1500 and 1560 cubic centimeters, and likely died of exhaustion.
Spontaneous Hypercholesterolemia and Arterial Lesions in Mice Lacking Apolipoprotein E
Authors: Zhang Sunny H. , Reddick Robert L. , Piedrahita Jorge A. , Maeda Nobuyo
Published: October 2006

Apolipoprotein E (apoE) is a ligand for receptors that clear remnants of chylomicrons and very low density lipoproteins. Lack of apoE is, therefore, expected to cause accumulation in plasma of cholesterol-rich remnants whose prolonged circulation should be atherogenic. ApoE-deficient mice generated by gene targeting were used to test this hypothesis and to make a mouse model for spontaneous atherosclerosis. The mutant mice had five times normal plasma cholesterol, and developed foam cell-rich depositions in their proximal aortas by age 3 months. These spontaneous lesions progressed and caused severe occlusion of the coronary artery ostium by 8 months. The severe yet viable phenotype of the mutants should make them valuable for investigating genetic and environmental factors that modify the atherogenic process.
Handling of Pregnant Rats: Effects on Emotionality of Their Offspring
Authors: Ader Robert , Conklin Peter M.
Published: October 2006

Pregnant rats were either unmanipulated or were handled for 10 minutes three times daily throughout pregnancy. Offspring remained with their natural mothers or were cross-fostered within and between experimental and control groups. When tested at 45 and 100 days of age, the offspring of handled mothers were found to be generally less emotional than the controls.
Particle Sorting by Repeated Freezing and Thawing
Authors: Corte Arturo E.
Published: October 2006

If a hetrogeneous mixture of particles of various sizes is frozen and thawed repeatedly, the particles are sorted into relatively uniform groups by size. The movement of particles depends on the amount of water between the ice-water interface and the particle, the rate of freezing, the distribution of the particles by size, and the orientation of the freeze-thaw plane.
Antigens and Enzymes Made Insoluble by Entrapping Them into Lattices of Synthetic Polymers
Authors: Bernfeld Peter , Wan J.
Published: October 2006

Biologically active, insoluble products have been prepared from soluble antigens or enzymes by entrapping them into the lattice of an insoluble, highly cross-linked synthetic polymer as it forms. Antigens, made insoluble, removed quantitatively certain or all antibiotics from complex mixtures. Seven enzymes so treated are described.
Xanthine Dehydrogenase: Differences in Activity among
Drosophila
Strains
Authors: Keller E. C. , Glassman Edward
Published: October 2006

In
Drosophila melanogaster
, mutants at two loci are known to lack detectable amounts of xanthine dehydrogenase activity. These are the maroon-like eye-color locus on the X chromosome and the rosy-eye-color locus on the third chromosome (52±). A survey was made of the xanthine dehydrogenase content of 98 wild-type strains of
D. melanogaster
. One strain with 25 percent of the xanthine dehydrogenase activity found in normal flies is described. Strains with high xanthine dehydrogenase activity have also been obtained by selection.
Acceptance or Rejection of Male Skin by Isologous Female Mice: Effect of Injection of Sperm
Authors: Katsh Grace F. , Talmage David W. , Katsh Seymour
Published: October 2006

Female C57B1/6J mice given one intraperitoneal injection of 1 to 8 million isologous epididymal sperm cells may exhibit either delayed or accelerated rejection of isologous male skin, depending on both the number of sperm cells injected and the time of application of the graft. A long time interval or a large dose of sperm cells results in maintenance of the male graft or delayed rejection, while a small dose and short time interval produces an accelerated rejection phenomenon.
Circularity of the Replicating Form of a Single-Stranded DNA Virus
Authors: Chandler Barbara , Hayashi M. , Hayashi M. N. , Spiegelman S.
Published: October 2006

Electron micrographs of purified replicating form DNA of the bacteriophage φX-174 show that it has ring structure. The circular property may explain both the abnormally high sedimentation coefficient and the great resistance of this DNA to irreversible heat denaturation. Intactness of the circle is required for the control of strand selection during transcription into complementary copies of RNA.
Peromyscus leucopus
: An Interesting Subject for Studies of Socially Induced Stress Responses
Authors: Southwick Charles H.
Published: October 2006

White-footed mice,
Peromyscus leucopus
, possess several characteristics which make them interesting subjects for the experimental study of social interactions and stress physiology: tolerance of very high cage densities among social congeners; marked behavioral intolerance among social strangers; exceptionally large adrenal glands; and adrenal and eosinophil responses sensitive to social disturbance.
Speech Durations of Astronaut and Ground Communicator
Authors: Matarazzo Joseph D. , Wiens Arthur N. , Saslow George , Dunham Richard M. , Voas Robert B.
Published: October 2006

Laboratory studies suggest that an interviewer can influence the speech duration of an interviewee by modifications in his own speech duration. What appears to be a related association between the speech duration of communicators on the ground and an astronaut in orbital flight was found.
Cretaceous Fossils Collected at Johnson Nunatak, Antarctica
Authors: Behrendt John C. , Laudon Thomas S.
Published: October 2006

Sandstone samples collected at 74°52′S, 74°02′W have been assigned a Cretaceous age on the basis of a faunal assemblage including Rotularia callosa (Stoliczka).
Calciphylaxis: Passive Transfer
Authors: Selye Hans , Gabbiani Giulio , Tuchweber Beatriz
Published: October 2006

Rats were sensitized by mouth with dihydrotachysterol and subsequently challenged by a subcutaneous injection of ferric dextran. Mineralization at the injection site is barely detectable 17 hours after challenge. If, at this time, the challenged skin is transplanted onto a normal recipient, mineralization continues in the nonsensitized host. Sensitization is indispensable only for the initiation of the calciphylactic response and, once "triggered," the mechanism for this type of mineralization is transferable.
Transferrins in Venezuelan Indians: High Frequency of a Slow-Moving Variant
Authors: Arends Tulio , Gallango M. L.
Published: October 2006

In 58 percent of the Yupa Indians of Venezuela there is a slow-moving transferrin electrophoretically indistinguishable from Tf D
Chi
, which to date, has only been found in Chinese. This finding is additional evidence for the existence of a racial link between South American Indians and Chinese.
Hybridization of Half Molecules of Rabbit Gamma Globulin
Authors: Nisonoff A. , Palmer J. L.
Published: October 2006

Specifically purified rabbit antiovalbumin and normal γ-globulin labeled with I-131 were dissociated into half molecules by reduction and acidification. When a mixture of the two preparations was neutralized, a large proportion of mixed molecules having active combining sites and the same sedimentation coefficient as the original γ-globulins was formed. Since the sulfhydryl groups were inactivated after reduction, the recombined subunits appear to be linked by noncovalent bonds.
Volatile Growth Inhibitors Produced by Aromatic Shrubs
Authors: Muller Cornelius H. , Muller Walter H. , Haines Bruce L.
Published: October 2006

Root growth of
Cucumis
and
Avena
seedlings is inhibited by volatile materials produced by leaves of
Salvia leucophylla
,
S. apiana
, and
Artemisia californica
. The toxic substance may be deposited when dew condenses on affected seedlings in the field.
Antiquity of American Polyploid Cotton
Authors: Smith C. Earle , MacNeish Richard S.
Published: October 2006

Fragments of a boll of
Gossypium hirsutum
L. from archeological excavations near Tehuacán, Mexico, prove that this species existed in 5800 B. C. No doubt remains that American tetraploid cotton species originated through natural hiybridization.