bluuebunny/crossref_metadata_2025 huggingface dataset:
Analogs of Cyclic Adenosine Monophosphate: Correlation of Inhibition of Purkinje Neurons with Protein Kinase Activation
Authors: Siggins G. R. , Henriksen S. J.
Published: October 2006

Cyclic adenosine monophosphate (cyclic AMP) and 11 derivatives were applied to rat cerebellar Purkinje cells by iontophoresis. Cyclic AMP inhibited 63 percent of the cells, while the 8-parachlorophenylthio- and 8-benzylthio- analogs of cyclic AMP inhibited the spontaneous firing of 92 and 80 percent of cells, respectively. The ability of the 11 analogs to inhibit neuronal firing correlated (r = + .78) with their reported potency in activating cyclic AMP-dependent protein kinase. These results extend previous studies, pointing to the mediation by cyclic AMP of the noradrenergic inhibition of Purkinje neurons, and provide new physiological evidence that protein phosphorylation is a major step in the action of cyclic AMP.
Molecular Biology of Prion Diseases
Authors: Prusiner Stanley B.
Published: October 2006

Prions cause transmissible and genetic neurodegenerative diseases, including scrapie and bovine spongiform encephalopathy of animals and Creutzfeldt-Jakob and Gerstmann-Straussler-Scheinker diseases of humans. Infectious prion particles are composed largely, if not entirely, of an abnormal isoform of the prion protein, which is encoded by a chromosomal gene. A posttranslational process, as yet unidentified, converts the cellular prion protein into an abnormal isoform. Scrapie incubation times, neuropathology, and prion synthesis in transgenic mice are controlled by the prion protein gene. Point mutations in the prion protein genes of animals and humans are genetically linked to development of neuro-degeneration. Transgenic mice expressing mutant prion proteins spontaneously develop neurologic dysfunction and spongiform neuropathology. Understanding prion diseases may advance investigations of other neurodegenerative disorders and of the processes by which neurons differentiate, function for decades, and then grow senescent.
Neural Symbolic Activity: A Psychophysical Measure
Authors: Weisstein Naomi
Published: October 2006

When a subject views a grating which is partially blocked from view by a cube, adaptation (decrease in contrast of the grating) occurs not only to the visible portions of the grating, but also to those portions blocked from view. This may indicate the existence of a neural mechanism which conveys the information "in back of."
An Inducible Bundle-Forming Pilus of Enteropathogenic
Escherichia coli
Authors: Girón Jorge A. , Ho Alice Suk Yue , Schoolnik Gary K.
Published: October 2006

Enteropathogenic
Escherichia coli
(EPEC), a cause of childhood diarrhea, grow on the surface of the small intestine and on cultured epithelial cells as colonies of adherent bacteria. When propagated on solid medium containing blood or attached to HEp-2 cells, EPEC express ropelike bundles of filaments, termed bundle-forming pili (BFP), that create a network of fibers that bind together the individual organisms. BFP were found to be expressed by five EPEC serogroups, each harboring a ∼92-kilobase plasmid previously known to be important for virulence in humans. When two of these strains were cured of this plasmid, they neither expressed BFP nor grew as adherent colonies. An antiserum to BFP reduced the capacity of EPEC to infect cultured epithelial cells. BFP are composed of a repeating subunit of 19,500 daltons, the amino-terminal amino acid sequence of this subunit is homologous to that of the toxin-coregulated pilin of
Vibrio cholerae
.
Antigenic Diversity Thresholds and the Development of AIDS
Authors: Nowak Martin A. , Anderson Roy M. , McLean Angela R. , Wolfs Tom F. W. , Goudsmit Jaap , May Robert M.
Published: October 2006

Longitudinal studies of patients infected with HIV-1 reveal a long and variable incubation period between infection and the development of AIDS. Data from a small number of infected patients show temporal changes in the number of genetically distinct strains of the virus throughout the incubation period, with a slow but steady rise in diversity during the progression to disease. A mathematical model of the dynamic interaction between viral diversity and the human immune system suggests the existence of an antigen diversity threshold, below which the immune system is able to regulate viral population growth but above which the virus population induces the collapse of the CD4
+
lymphocyte population. The model suggests that antigenic diversity is the cause, not a consequence, of immunodeficiency disease. The model is compared with available data, and is used to assess how the timing of the application of chemotherapy or immunotherapy influences the rate of progress to disease.
Sulfate-Binding Protein from
Salmonella typhimurium
: Physical Properties
Authors: Langridge Robert , Shinagawa Hideo , Pardee Arthur B.
Published: October 2006

This protein binds sulfate strongly and is implicated in sulfate transport in
Salmonella typhimurium
. It has a molecular weight of 32,000 and an axial ratio of 4:1. Crystals are elongate prisms up to 0.5 millimeter. X-ray diffraction photographs give discrete crystalline reflections to a spacing of at least 2 angstroms. The unit cell is orthorhombic
P
2
1
2
1
2
1
, with four molecules per unit cell of 40.8 by 47.5 by 136 angstroms. This is consistent with a highly asymmetric molecule such as the prolate ellipsoid suggested by the other physical measurements. Addition of sulfate had minimum effects on the physical properties as measured by light absorption, optical rotary dispersion, circular dichroism, fluorescence and its depolarization, nuclear magnetic resonance, and sedimentation velocity.
Biological Nitrogen Fixation in Lake Erie
Authors: Howard David L. , Frea James I. , Pfister Robert M. , Dugan Patrick R.
Published: October 2006

Biological nitrogen fixation, as determined by acetylene reduction, occurs in Lake Erie. Fixation potential by blue-green algae in situ in water and by bacteria in collected sediments was demonstrated. Nitrogen-fixing activity occurred from June through November suggesting that it is significant over the extremes of seasonal variation in light, temperature, and nutrients.
Microtubular Spherulites: Development and Growth in Solutions of Bacteriochlorophyll Protein
Authors: Olson Rodney A.
Published: October 2006

Macromolecules of the water-soluble complex of bacteriochlorophyll protein can assemble in vitro to form fully developed spherulites composed of radiating microtubules. The changes that occur in the pattern of long-range order during the growth of these structures are typical of the development of the spherulitic crystal habit in numerous other materials of nonbiological origin.
Carbon Dioxide-Fixation in Photosynthetic Green Sulfur Bacteria
Authors: Sirevåg Reidun , Ormerod J. G.
Published: October 2006

The main products of carbon dioxide-fixation in washed suspensions of
Chlorobium thiosulfatophilum
are a polyglucose, α-ketoglutarate, and α-keto-β-methylvalerate. All of these can be formed by a mechanism involving the reductive carboxylic acid cycle. The reductive pentose phosphate cycle appears to play a quantitatively minor role in carbon dioxide-fixation under these conditions.
Double-Helical Polynucleotides: Immunochemical Recognition of Differing Conformations
Authors: Stollar B. D.
Published: October 2006

Rabbit antibodies to double-helical RNA react by complement fixation with synthetic or natural double-strand RNA but not with native DNA. In turn, human (from systemic lupus erythematosus patients) antibodies to native DNA do not react with double-strand RNA. Both types of antibodies show cross-reactions (from 1 percent to 50 percent) with RNA-DNA hybrids, but antibodies to the hybrids do not react at all with double-strand RNA or with native DNA. Antibodies to polydeoxyguanylate⋅polydeoxycytidylate also failed to react with native DNA.
Wheat Leaf Rust: Control by 4-
n
-Butyl-1,2,4-triazole, a Systemic Fungicide
Authors: von Meyer William C. , Greenfield Stanley A. , Seidel Michael C.
Published: October 2006

Compound 4
-n-
butyl-1,2,4-triazole was demonstrated as an enduring and selective systemic fungicide for the control of wheat leaf rust by foliar and soil applications. Among several species of rust fungi treated, only wheat leaf rust
(Puccinia recondita
Rob.
)
was controlled. Wheat stem rust, for example, was unaffected by either soil or foliar applications.
Oxychlordane, Animal Metabolite of Chlordane: Isolation and Synthesis
Authors: Schwemmer Bruce , Cochrane William P. , Polen Percy B.
Published: October 2006

Oxychlordane (C
10
H
4
Cl
8
O), a minor heretofore unidentified metabolite, was isolated from fat of pigs on diets heavily dosed with pure isomers of the insecticide, chlordane (C
10
H
6
Cl
8
). Chemical and spectroscopic evidence provides bases for proposal of structure of the metabolite as 1

-exo-
2
-endo-
4,5,6,7,8,8-octachloro-2,3
-exo-
epoxy-2,3,3a,4,7,7a-hexahydro-4,7-methanoindene.
Dental Enamel: Detection of Surface Changes by Ultrasound
Authors: Lees Sidney , Barber Frank E. , Lobene Ralph R.
Published: October 2006

Evidence indicates that the tooth surface differs in structure from the enamel immediately beneath it, and particularly that the enamel rod type structure is minimal in the true natural surface. Furthermore, the rod ends appear to disappear with age after the eruption of the tooth. The thickness of the surface layer may be as much as 25 micrometers. Studies of caries incidence show a peak in the attack curve 2 to 4 years after eruption and a decline thereafter for all teeth. This information indicates that the mechanical structure of the tooth surface should be carefully studied. A highly useful means appears to be ultrasound since the specific acoustic impedance of highly mineralized tissue like enamel is strongly dependent on fraction volume mineralization and since non-destructive test techniques can be based on ultrasonics. An experimental demonstration of ultrasonic detection in vitro of tooth surface demineralization is given.
Shared Human T Cell Receptor V
β
Usage to Immunodominant Regions of Myelin Basic Protein
Authors: Wucherpfennig Kai W. , Ota Kohei , Endo Noriaki , Seidman J. G. , Rosenzweig Anthony , Weiner Howard L. , Hafler David A.
Published: October 2006

Multiple sclerosis (MS) may be an autoimmune disease mediated by T cells specific for a myelin protein. Investigations have demonstrated myelin basic protein (MBP)-reactive T cells that were activated in vivo in MS patients, suggesting that MBP may be a target antigen in MS. The variable (V) region of the T cell receptor (TCR) β chain was examined among 83 T cell lines from both MS patients and healthy subjects that were reactive with the immunodominant region of human MBP (residues 84 to 102) or with a second immunodominant region of MBP (143 to 168). V
β
17 and to a lesser extent V
β
12 were frequently used in recognition of MBP(84-102) among different individuals. In contrast, V
β
17 was very infrequent among lines reactive with MBP (143-168). These data demonstrate shared TCR V
β
gene usage for the recognition of immunodominant regions of the human autoantigen MBP. Such TCR structures may be used as targets for specific immunotherapy in MS.
Identification of an Inhibitor of Neovascularization from Cartilage
Authors: Moses Marsha A. , Sudhalter Judith , Langer Robert
Published: October 2006

Certain tissues such as cartilage are resistant to vascular invasion, yet no single tissue-derived molecule that can inhibit angiogenesis has been reported. A protein derived from cartilage was purified that inhibits angiogenesis in vivo and capillary endothelial cell proliferation and migration in vitro in three separate bioassays. This protein is also an inhibitor of mammalian collagenase. These findings may help elucidate the mechanisms by which neovascularization is controlled in both normal and pathological states.
Prevention of Activated Neutrophil Adhesion to Endothelium by Soluble Adhesion Protein GMP140
Authors: Gamble Jennifer R. , Skinner Michael P. , Berndt Michael C. , Vadas Mathew A.
Published: October 2006

Neutrophils and monocytes, but not lymphocytes, adhered strongly to plastic surfaces coated with GMP140, a protein of endothelial cells and platelets. This adhesion of neutrophils was mediated by GMP140 and not by the CD18 integrin complex. By contrast, GMP140 in solution inhibited the CD18-dependent adhesion of tumor necrosis factor-α-activated neutrophils to plastic surfaces and resting endothelium, but not of resting neutrophils to tumor necrosis factor-α-activated endothelium. Thus, the binding of a soluble form of an adhesion protein selectively inhibited another set of adhesive events. Soluble GMP140 may be important in maintaining the nonadhesiveness of neutrophils in the circulation and may serve to limit inflammatory reactions.
Birth of Projection Neurons in Adult Avian Brain May Be Related to Perceptual or Motor Learning
Authors: Alvarez-Buylla Arturo , Kirn John R. , Nottebohm Fernando
Published: October 2006

Projection neurons that form part of the motor pathway for song control continue to be produced and to replace older projection neurons in adult canaries and zebra finches. This is shown by combining [
3
H]thymidine, a cell birth marker, and fluorogold, a retrogradely transported tracer of neuronal connectivity. Species and seasonal comparisons suggest that this process is related to the acquisition of perceptual or motor memories. The ability of an adult brain to produce and replace projection neurons should influence our thinking on brain repair.
Psychological and Social Barriers to Women in Science
Authors: White Martha S.
Published: October 2006

Commitment and creativity in science are not merely a function of an individual's competence or excellence, but are a product of the social environment as well. Acceptance and recognition from significant other people (one's peers and other professionals), and opportunities for stimulating and challenging interaction are essential for developing a strong occupational or professional identity, and for creating the inner sense of role competence which can lead to greater commitment and productivity in professional work. Unfortunately women, especially those who have experienced interrupted or discontinuous careers, find such opportunities and acceptance difficult to obtain.
Intelligence Quotient Pattern over Age: Comparisons among Siblings and Parent-Child Pairs
Authors: McCall Robert B.
Published: October 2006

Comparisons between sibling and parent-child pairs with unrelated control pairs matched for year of birth and parental education were made to determine the relative heritability of the general level of intelligence quotient as opposed to that of the sequential pattern of IQ change over age (3 to 12 years). There was greater similarity among related siblings relative to matched controls for general level than for pattern of IQ over age. Relationships between the IQ's of children and that of their parents as children were not consistent across age.
Hydroxy-L-proline- and 2,2′-Dipyridyl-Induced Phenovariations in the Liverwort
Nowellia curvifolia
Authors: Basile D. V.
Published: October 2006

Two antagonists of "normal" proline-hydroxyproline-protein synthesis, 2,2′-dipyridyl and hydroxy-L-proline, induced the same kind of phenovariation in
Nowellia curvifolia
(Dicks) Mitt. (Cephaloziaceae) as they do in
Scapania nemorosa
(Scapaniaceae). This finding supports a hypothesized cardinal role for proline-hydroxyproline-protein in modulating aspects of morphogenesis and phylogeny in the leafy liverworts.
Thermal Transitions in Human Plasma Low Density Lipoproteins
Authors: Deckelbaum R. J. , Shipley G. G. , Small D. M. , Lees R. S. , George P. K.
Published: October 2006

Thermal analysis of human plasma low density lipoproteins reveals a broad reversible transition encompassing body temperature. The calorimetric and x-ray scattering data identify this transition as a cooperative, liquid-crystalline to liquid phase change involving the cholesterol esters in the lipoprotein. This behavior requires the presence of a region rich in cholesterol ester within the lipoprotein.
FTZ-F1, a Steroid Hormone Receptor-like Protein Implicated in the Activation of
fushi tarazu
Authors: Lavorgna Giovanni , Ueda Hitoshi , Clos Joachim , Wu Carl
Published: October 2006

The
Drosophila
homeobox segmentation gene
fushi tarazu
(
ftz
) is expressed in a seven-stripe pattern during early embryogenesis. This characteristic pattern is largely specified by the zebra element located immediately upstream of the
ftz
transcriptional start site. The FTZ-F1 protein, one of multiple DNA binding factors that interacts with the zebra element, is implicated in the activation of
ftz
transcription, especially in stripes 1, 2, 3, and 6. An FTZ-F1 complementary DNA has been cloned by recognition site screening of a
Drosophila
expression library. The identity of the FTZ-F1 complementary DNA clone was confirmed by immunological cross-reaction with antibodies to FTZ-F1 and by sequence analysis of peptides from purified FTZ-F1 protein. The predicted amino acid sequence of FTZ-F1 revealed that the protein is a member of the nuclear hormone receptor superfamily. This finding raises the possibility that a hormonal ligand affects the expression of a homeobox segmentation gene early in embryonic development.
Supraoptic Neurosecretory Cells: Adrenergic and Cholinergic Sensitivity
Authors: Barker Jeffery L. , Crayton John W. , Nicoll Roger A.
Published: October 2006

Adrenergic and cholinergic agonists and antagonists were applied microelectrophoretically to over 700 neurons in the cat supraoptic nucleus, 20 percent of which were antidromically identified as neurosecretory cells. Norepinephrine uniformly depressed all sensitive cells. Acetylcholine caused both muscarinic depression and nicotinic excitation which were antagonized by atropine and dihydro-β-erythroidine, respectively. These results support the hypothesis that norepinephrine and acetylcholine are directly involved in controlling the release of antidiuretic hormone.
Development of Excitability in Embryonic Muscle Cell Membranes in Certain Tunicates
Authors: Takahashi Kunitaro , Miyazaki Shun-ichi , Kidokoro Yoshiaki
Published: October 2006

During the course of development of muscle cells in certain tunicates, a sign of regenerative membrane response appears in the gastrula stage. In the early tadpole larva, the action potential consists of a spike followed by a plateau. The latter-disappears in fully differentiated cells, conceivably in association with the establishment of delayed rectification.
Mammalian Scent Marking
Authors: Ralls Katherine
Published: October 2006

Mammals mark frequently in any situation where they are both intolerant of and dominant to other members of the same species. In other words, they mark when they are likely to attack another member of the same species, and are likely to win if they do attack. Such a situation occurs, as Hediger pointed out, in connection with territoriality but it also occurs in other kinds of social systems. Frequent, vigorous marking occurs at times when there is reason to infer that the animal is motivated to aggression. The effects of marks and marking upon other individuals are poorly understood. Many species mark with more than one source of scent in response to one stimulus or set of stimuli.
Hydrocarbon Sex Pheromone in Tiger Moths (Arctiidae)
Authors: Roelofs Wendell L. , Cardé Ring T.
Published: October 2006

2-Methylheptadecane is a sex pheromone compound in many sibling species of the
Holomelina aurantiaca
complex, in
Holomelina laeta
, and in
Pyrrharctia isabella
, which are all arctiids. Habitat preference, temporal distribution, and differing diurnal cycles help effect reproductive isolation among the species, but secondary sex pheromone chemicals are also suggested by the field studies.
Solvent Dependence of the Luminescence of
N
-Arylaminonaphthalenesulfonates
Authors: Seliskar Carl J. , Brand Ludwig
Published: October 2006

N
-Methyl,
N
-phenyl-2-aminonaphthalene-6-sulfonate, a fluorescence probe, adsorbs to cycloheptaamylose with a stoichiometry of 1 : 1. The fluorescence of the complex is similar to that observed when the dye is dissolved in organic solvents. Similar fluorescence is observed with the dye in ice. The results are interpreted in terms of "solvent" relaxation during the excited state lifetime of the dye.
Sex Stimulant and Attractant in the Indian Meal Moth and in the Almond Moth
Authors: Brady U. Eugene , Tumlinson James H. , Brownlee Robert G. , Silverstein Robert M.
Published: October 2006

cis
-9,
trans
-12-Tetradecadien-1-yl acetate was isolated from the female Indian meal moth,
Plodia interpunctella
(Hübner), and the female almond moth,
Cadra cautella
(Walker). It is the major if not the sole component of the sex stimulatory and attractant pheromone of female
Plodia
. It is present in the pheromone of the female
Cadra
along with at least one synergist.
Bone Marrow Transplantation
Authors: Congdon C. C
Published: October 2006

The goals in bone marrow transplantation are its application to the treatment of diseases arising in the blood-forming tissues of man. Techniques for procuring and grafting marrow are of the needle-and-syringe type and are based on the normal physiological processes in which stem cells circulate through blood and other fluids of the mammalian organism. Destruction of bone marrow by irradiation, chemicals, or unknown agencies provides the immediate experimental system for demonstrating the therapeutic value of marrow transplants. Genetic diseases characterized by abnormal marrow function are also modifiable by grafts of blood-forming tissues. Studies with identical twins are critical experiments for showing the clinical value of grafts, even though the transplanted cells cannot be identified by the usual marker techniques. Among the best results seen with marrow grafting is the presumed cure of certain rare hereditary immune-deficiency disorders of children.

A major problem in bone marrow transplantation—one that delays its wider clinical application—is the immune reaction from cells growing out of the foreign transplant which attack the host (the graft-versus-host reaction). Attempts to use a graft-versus-host response to eliminate tumor cells is a part of the marrow research program.

The history of the processes that led to some of the achieved goals in marrow grafting shows the usual multicentric origin of an idea. Certain individuals play critical roles in developing the idea. Finally, a body of knowledge is accumulated that opens up or limits prospects for the future.

In bone marrow transplantation, future achievements will depend in part on the progress that is made in the areas of cell separation, bone marrow banking, and tissue culture.
Oscillator Neurons in Crustacean Ganglia
Authors: Mendelson Martin
Published: October 2006

The motor rhythm of ventilation in hermit crabs and lobsters appears to be controlled by a pair of neurons, one in each half of the subesophageal ganglion. Their membrane potentials oscillate and upon depolarization and hyperpolarization elicit spiking in two pools of motor neurons on each side, without spikes in the oscillator neurons themselves. The fact that higher order (command) interneurons can control the rate of the oscillator by means of a smoothly graded input lends support to the idea that oscillator neurons respond periodically to a constant ionic stimulus.
Synaptic Facilitation: Long-Term Neuromuscular Facilitation in Crustaceans
Authors: Sherman R. G. , Atwood H. L.
Published: October 2006

Continuous stimulation at frequencies equal to or greater than 5 hertz for 20 to 30 minutes results in a two- to fivefold increase in the amplitudes of excitatory postsynaptic potential recorded from certain stretcher and opener muscles of decapod crustaceans. This long-term facilitation appears to result from an accumulation of sodium ions within the nerve terminals. It persists for at least 1 hour after stimulation has stopped.
American Children with Reading Problems Can Easily Learn to Read English Represented by Chinese Characters
Authors: Rozin Paul , Poritsky Susan , Sotsky Raina
Published: October 2006

With 2.5 to 5.5 hours of tutoring, eight second-grade inner-city school children with clear reading disability were taught to read English material written as 30 different Chinese characters. This accomplishment eliminates certain general interpretations of dyslexia, for example, as a visual-auditory memory deficit. The success of this program can be attributed to the novelty of the Chinese orthography and to the fact that Chinese characters map into speech at the level of words rather than of phonemes. It is proposed that much reading disability can be accounted for in terms of the highly abstract nature of the phoneme (the critical unit of speech in alphabetic systems) and that an intermediate unit, such as the syllable, might well be used to introduce reading.
Organophosphorus and Methyl Carbamate Insecticide Teratogenesis: Diminished NAD in Chicken Embryos
Authors: Proctor Nick H. , Casida John E.
Published: October 2006

Studies with 36 organophosphorus and 12 methyl carbamate compounds establish a correlation between reduction in nicotinamide adenine dinucleotide (NAD) levels and severity of teratogenic signs in chicken embryos, a relation supported by reversal of these effects by nicotinamide derivatives. Diminished NAD occurring at organophosphorus and methyl carbamate concentrations as low as 0.6 to 2.0 parts per million in the egg constitutes a newly recognized biochemical lesion induced by the two most important classes of insecticide chemicals.
Production of Globules in Mouse L Cells Penetrated with Hamster Sperms
Authors: Lau L. Cho-tuen
Published: October 2006

Globule formation has been observed in long-term cultures of mouse L cells penetrated with hamster spermatozoa. These numerous, uniform, and spherical structures are approximately 10 micrometers in diameter when formed, and are positive to stains specific for proteins and nucleic acids. They may be produced either by sperms within their target cells or by the cells in response to penetration by the spermatozoa.
Mycorrhizal Enhancement of Water Transport in Soybean
Authors: Safir G. R. , Boyer J. S. , Gerdemann J. W.
Published: October 2006

Mycorrhizae produced by
Endogone mosseae
decrease the resistance to water transport in soybean
(Glycine max
L.). The decrease was associated with an increase in the growth of shoots but not of roots.
Vitamin D
3
: Induction of Calcium-Binding Protein in Embryonic Chick Intestine in Vitro
Authors: Corradino R. A. , Wasserman R. H.
Published: October 2006

Induction of the synthesis of calcium-binding protein in chick embryonic intestine maintained in vitro was accomplished by simply adding vitamin D
3
to the culture medium. Accompanying the induction of this protein, there was enhanced radiocalcium uptake by the intestine. These observations represent the first demonstration of an in vitro physiological effect of vitamin D
3
on the calcium absorptive mechanism of the intestine.
Lymph Node Cells: Their Differential Capacity to Induce Tolerance of Heart and Skin Homografts in Rats
Authors: Barker Clyde F. , Lubaroff David M. , Silvers Willys K.
Published: October 2006

Rats of the BN strain, inoculated at birth with (Lewis × BN)F
1
hybrid lymph node cells are not tolerant of Lewis skin grafts but do display high degrees of tolerance of Lewis hearts.
Satellites of the Outer Planets: Thermal Models
Authors: Lewis John S.
Published: October 2006

Steady-state thermal models for the large satellites of the outer planets strongly indicate that their interiors are currently maintained at temperatures well above the ice-ammonia eutectic temperature by the decay of long-lived radioisotopes of potassium, uranium, and thorium. The present-day steady-state thermal structure of a representative satellite, J IV (Callisto), is shown to be characterized by the presence of a thin icy crust over a deep liquid mantle, with a dense core of hydrous silicates and iron oxides. Some dynamical consequences of this model are briefly discussed.
Duchenne Muscular Dystrophy: Functional Ischemia Reproduces Its Characteristic Lesions
Authors: Mendell J. R. , Engel W. King , Derrer E. C.
Published: October 2006

The highly characteristic early and midstage histological lesions of Duchenne dystrophy were reproduced experimentally in the rat by the combination of a vascular abnormality, aortic ligation, which does not affect the structure of the intramuscular blood vessels, and the humoral vasoactive substance 5-hydroxytryptamine. Neither ligation nor injection of 5-hydroxytryptamine alone causes changes in the muscle fibers. This result establishes the possibility of a similar combined mechanism for a nonstructural ischemia pathogenesis in Duchenne dystrophy. The proposed pathogenesis is contrary to the generally held idea that the cause is an intrinsic abnormality of muscle fiber metabolism.
Attention-Related Increases in Cortical Responsivity Dissociated from the Contingent Negative Variation
Authors: Donald Merlin W. , Goff William R.
Published: October 2006

Certain tasks which increase attention to stimuli also elicit the contingent negative variation and increase the amplitude of the P300 component of the sensory evoked response. Therefore it appeared possible that the contingent negative variation and attention-related increases in P300 are either confounded by artifact or generated by common neural mechanisms. The fact that we have recorded attention-related increases in P300 amplitude independent of corresponding systematic changes in contingent negative variation indicates that neither of these possibilities is correct. The two phenomena are independently variable modulations of cortical activity.
Net Kinetic Energy in Littoral Transport
Authors: Tanner William F.
Published: October 2006

Studies of coastal erosion and coastal management can be put on a firm physical basis only after methods have been developed for closely estimating the energy expended in actual unidirectional net littoral transport of sediment. Such measures have now been obtained for six coastal drift cells. The results, for a 68-year period, vary from a minimum of 0.6 × 10
4
ergs (very low energy) to a maximum of 340 × 10
4
ergs (moderately high energy) per cell.
Reaction of Reindeer to Obstructions and Disturbances
Authors: Klein David R.
Published: October 2006

In Scandinavia, highways and railroads have not generally created obstructions to the movement of domesticated reindeer, although thousands of animals are killed each year in accidents. Some disruption in the movements of wild reindeer in Norway has been associated with the construction of a railroad and highway through an alpine plateau south of Trondheim.

Hydroelectric projects have had the greatest detrimental effects on reindeer by flooding rangelands and obstructing migration routes. Special problems are created by the fluctuating water levels in reservoirs and rivers; efforts to mitigate the effects of these fluctuations have been only partially successful. Reindeer have strong traditions for migrating along specific routes, and realignment of these routes is extremely difficult.

Conflicts of interest exist between reindeer herders and foresters. During their winter feeding, the deer damage young trees. The cutting of forests usually results in a deterioration of the area as a rangeland for reindeer. Herbicides used in forestry have been implicated in the death of some reindeer in Sweden, and research is now under way to determine the effects of herbicides on reindeer.

The increased use of fences in reindeer husbandry in Scandinavia has emphasized the fact that reindeer behavior and characteristics of the terrain must be considered if fences are to be successful in directing or controlling the movements of reindeer. Herders now use snowmobiles instead of reindeer for transportation and herding, but the machines disturb the reindeer and must be used with discretion.

Recent evidence indicates that large amounts of industrial waste in the atmosphere are carried from the British Isles and central Europe to Scandinavia, where they fall out in rain and snow. This has raised concern about the influence of the wastes on lichens, the main winter food supply of reindeer. Studies are now under way in Finland, Sweden, and Norway, through the International Biological Program, to determine the growth rates of the several lichen species that are important to reindeer.
Cultivation of
Borrelia hermsi
Authors: Kelly Richard
Published: October 2006

A medium has been developed which permits the isolation and growth of Borrelia hermsi, an organism that causes relapsing fever.
Ultrahigh-Frequency Electromagnetic Fields for Weed Control: Phytotoxicity and Selectivity
Authors: Davis F. S. , Wayland J. R. , Merkle M. G.
Published: October 2006

An ultrahigh-frequency electromagnetic field (2450±20 megahertz) is lethal to plants and seeds of several species after relatively short exposure times. Some species are highly susceptible; others are relatively resistant to a given field intensity. Phytotoxicity is increased in imbibed seeds and young plants. It is decreased in dry seeds and sometimes decreased in mature plants. Soil partially attenuates the field but is not opaque to it.
Amino Acids Indigenous to the Murray Meteorite
Authors: Lawless James G. , Kvenvolden Keith A. , Peterson Etta , Ponnamperuma Cyril , Moore Carleton
Published: October 2006

Analysis of the Murray meteorite, a type II carbonaceous chondrite, has led to the identification of 17 amino acids. For seven of the amino acids nearly equal amounts of the D and L isomers are present, and 11 of the amino acids are not found in protein. These results suggest that these amino acids, like the amino acids of the Murchison meteorite, are extraterrestrial in origin.
Marihuana and Memory: Acquisition or Retrieval?
Authors: Abel Ernest L.
Published: October 2006

Two experiments were conducted to determine the means by which marihuana affects human memory. The results of these studies indicated that marihuana did not affect retrieval of information in memory when the method of free recall was used, but did affect recognition processes such that subjects were less able to discriminate between items that had been presented previously and items that had not appeared a short time before. With respect to initial learning, marihuana was shown to affect acquisition processes involved in the storage of information.
Lymphocyte DNA Synthesis Inhibition
Authors: Houck John C. , Irausquin Hiltje , Leikin Sanford
Published: October 2006

A specific endogenous inhibitor for lymphocyte DNA synthesis that can be isolated from the lymphoid system and which is probably cell specific is described. The inhibitor is thermolabile, is destroyed by trypsin, and has a mass of about 30,000 to 50,000 daltons.
Methyl Mercury and Inorganic Mercury Collection by a Selective Chelating Resin
Authors: Law Stephen L.
Published: October 2006

A commercially available chelating resin selectively and quantitatively collects methyl mercuric and inorganic mercuric forms of mercury to the exclusion of all other metals studied, except the noble metals. Both forms of mercury can be collected from
p
H 1 to 9. Collected mercury is readily eluted with a slightly acid, 5 percent solution of thiourea, and the resin can be reused for many cycles. Selectivity,
p
H effects, capacity, and elution characteristics of the resin are described. A resin-loaded paper composed of 50 percent resin and 50 percent cellulose shows properties similar to those of the loose resin.
Polyadenylic Acid Sequences: Role in Conversion of Nuclear RNA into Messenger RNA
Authors: Darnell J. E. , Philipson L. , Wall R. , Adesnik M.
Published: October 2006

Polyadenylic acid [poly(A)] segments containing 150 to 250 nucleotides appear to be covalently linked to heterogeneous nuclear RNA (HnRNA) and messenger RNA (mRNA) in eucaryotic cells. The poly(A) is synthesized in the nucleus, and is probably linked initially to HnRNA that is ultimately transported as mRNA to the cytoplasm. Studies with inhibitors of RNA or poly(A) synthesis indicate that synthesis of poly(A) segments is independent of transcription. The poly(A) marker may prove useful to elucidate mRNA modification and transport in eucaryotic cells.
Martian Craters and a Scarp as Seen by Radar
Authors: Pettengill G. H. , Rogers A. E. E. , Shapiro I. I.
Published: October 2006

Radar observations of Mars with a surface resolution of 1.3° in latitude and 0.8° in longitude have been carried out during the opposition of 1971. With a precision in surface height measurement approaching 75 meters in regions of high reflectivity, it has been possible to measure the detailed characteristics of a number of craters. Many of these can be identified with craters shown in Mariner photographs of Mars. In addition, a scarp has been seen at 41° west, 14° south with an average slope of about 6° extending over about 40 kilometers.
The Xenon Record of Extinct Radioactivities in the Earth
Authors: Boulos Mervet S. , Manuel Oliver K.
Published: October 2006

Analyses of xenon from well gas rich in carbon dioxide reveal a large excess of radiogenic xenon-129 from the decay of extinct iodine-129. Smaller excesses observed in the heavy xenon isotopes are from fission. These results place narrow limits on any age difference between the earth and the oldest meteorites. The occurrence of excess radiogenic xenon-129 in well gas also suggests that any quantitative degassing of existing solid materials to form the atmosphere must have been limited to a very early period of the earth's history, approximately the first 10
8
years. Alternatively, this observation is consistent with a model of the earth's continuous, but still incomplete, degassing since its time of formation.
Isolation and Characterization of Larvicidal Principle of Garlic
Authors: Amonkar S. V. , Banerji A.
Published: October 2006

The larvicidal principles of garlic,
Allium sativum
L., have been isolated and identified as diallyl disulfide and diallyl trisulfide. Both natural and synthetic samples of these larvicides are fatal at 5 parts per million to
Culex pipiens quinquefasciatus
Say.
Magma Supply Rate at Kilauea Volcano, 1952-1971
Authors: Swanson Donald A.
Published: October 2006

The three longest Kilauea eruptions since 1952 produced lava at an overall constant rate of about 9 × 10
6
cubic meters per month (vesicle-free). This is considered to represent the rate of magma supply from a deep source, probably the mantle, because little or no summit deformation indicating high-level storage accompanied any of the three eruptions.
Copper on Intrauterine Devices Stimulates Leukocyte Exudation
Authors: Cuadros Alvaro , Hirsch James G.
Published: October 2006

Metallic copper in the uterine or abdominal cavities of rats or monkeys stimulates an impressive local exudation of polymorphonuclear leukocytes. This cellular response to copper persists for at least 7 months, without significant local tissue damage or detectable systemic effects on the test animal. This finding provides a possible explanation for the capacity of copper to increase impressively the antifertility effect of polyethylene intrauterine contraceptive devices.
Genes Conferring Specific Plant Disease Resistance
Authors: Shepherd K. W. , Mayo G. M. E.
Published: October 2006

Genes conferring host resistance to an obligate parasite, grouped together in complex loci provide opportunities to study their structure. By means of an appropriate operational definition of these genes, a modified
cis-trans
test was used to interpret the position effects of codominant genes mutually recombined within each of two complex loci of flax, with the use of a specially developed method of analysis among F
2
segregants. The different behavior of genes in the
M
and
L
groups may reflect a difference in their structure sufficient to raise important implications in the theory of specific host-parasite interactions.
Rubidium-Strontium and Potassium-Argon Age of Lunar Sample 15555
Authors: Murthy V. Rama , Evensen N. M. , Jahn Bor-Ming , Coscio M. R. , Dragon J. C. , Pepin R. O.
Published: October 2006

The lunar mare basalt 15555 from the edge of Hadley Rille has been dated at 3.3 × 10
9
years by both rubidium-strontium and potassium-argon techniques. Age and trace element abundances closely resemble those of the Apollo 12 mare basalts. Data from lunar basalts obtained thus far indicate that they cannot be derived by simple fractionation from a homogeneous source.
Tetraploid Origin of the Karyotype of Catostomid Fishes
Authors: Uyeno Teruya , Smith G. R.
Published: October 2006

Catostomid fishes appear to have 2
n
(→4
n
?) ≃ 100 chromosomes. The Cyprinidae, from which catostomids probably diverged before the Eocene, usually have 2
n
= 48 or 50 chromosomes. Preliminary cytophotometric measurements indicate an approximate doubling of DNA content of cells among catostomids.
Spermatogenesis in Cultured Testes of the Cynthia Silkworm: Effects of Ecdysone and of Prothoracic Glands
Authors: Kambysellis Michael P. , Williams Carroll M.
Published: October 2006

In vitro spermatogenesis takes place when intact testes are cultured in blood plasma containing ecdysone or certain other steroids possessing ecdysone activity. The ecdysone requirement can be satisfied by culturing the testes in the presence of living, active prothoracic glands. The most likely explanation of these results is that the prothoracic glands constitute the principal source of ecdysone.
Ion Microprobe Mass Analyzer
Authors: Andersen C. A. , Hinthorne J. R.
Published: October 2006

The quantitative analyses and other applications described in this article indicate a useful future for the ion-microprobe mass analyzer in many areas of the science of solid materials. It should be possible to analyze all the elements quantitatively, but detection sensitivities will vary depending on the matrix, the element, and the polarity of the sputtered ion being studied. Most elements will have optimum yields in the spectrum of positive sputtered ions, and will be detected in concentrations of parts per million in micrometer-sized sampling areas. Electronegative elements will be detected with similar sensitivities in the spectrum of negative sputtered ions, but inert gases, which are ionized with difficulty and have small electron affinities, will be detected with considerably poorer sensitivities. In general, it will be possible to measure isotope ratios without chemical separation of the constituent elements of the sample. The precision of an ion microprobe isotope ratio measurement depends basically on the counting rates involved, and its accuracy can approach its precision if auxiliary standards are used. The isotope ratios of different elements can be compared readily because of the small mass-discrimination effects of the system. Surface layers can be quantitatively analyzed in depth with a resolution of tens of angstroms; hence, it should be possible to study the migration of atoms.
Mercury Concentrations in Museum Specimens of Tuna and Swordfish
Authors: Miller G. E. , Grant P. M. , Kishore R. , Steinkruger F. J. , Rowland F. S. , Guinn V. P.
Published: October 2006

The mercury levels of museum specimens of seven tuna caught 62 to 93 years ago and a swordfish caught 25 years ago have been determined by instrumental neutron activation analysis. These levels are in the same range as those found in specimens caught recently.
Magnetic Noise Preceding the August 1971 Summit Eruption of Kilauea Volcano
Authors: Keller George V. , Jackson Dallas B. , Rapolla Antonio
Published: October 2006

During the course of an electromagnetic survey about Kilauea Volcano in Hawaii, an unusual amount of low-frequency noise was observed at one recording location. Several weeks later an eruption occurred very close to this site. The high noise level appeared to be associated in some way with the impending eruption.
Carboxyhemoglobin Elevation after Exposure to Dichloromethane
Authors: Stewart Richard D. , Fisher Terrance N. , Hosko Michael J. , Peterson Jack E. , Baretta Edward D. , Dodd Hugh C.
Published: October 2006

Inhalation of dichloromethane vapor in concentrations of 500 to 1000 parts per million for 1 to 2 hours promptly initiated the formation of significant quantities of carbon monoxide in human subjects. The evidence suggests that carbon monoxide may be a metabolite of dichloromethane and that exposure to concentrations of dichloromethane below the industrial threshold limit values may result in the formation of carbon monoxide in amounts that exceed the allowable limits.
Decay of Information in Short-Term Memory
Authors: Wingfield Arthur , Byrnes Dennis L.
Published: October 2006

Self-paced recall in Broadbent's simultaneous listening task shows particular temporal patterns associated with report strategies. Accuracy is a decreasing function of the interval between presentation and report of an item, irrespective of report strategy. Results are related to an interaction between strategies of response selection and decay of information from memory.
DDT: Inhibition of Sodium Chloride Tolerance by the Blue-Green Alga
Anacystis nidulans
Authors: Batterton J. C. , Boush G. M. , Matsumura F.
Published: October 2006

Anacystis nidulans
, a freshwater blue-green alga, has been found to tolerate sodium chloride (1 percent by weight) and DDT [1,1,1-trichloro-2,2-bis)
p
-chlorophenyl) ethane] (800 parts per billion) separately, but growth was inhibited in the presence of both compounds. This inhibition was reversed by an increased calcium concentration. It is possible that inhibition of (Na
+
,K
+
)-activated adenosine triphosphatase) by DDT causes this species to lose the ability to tolerate sodium chloride.
Ultrasonic Doppler Technique for Imaging Blood Vessels
Authors: Reid John M. , Spencer Merrill P.
Published: October 2006

Present ultrasonic Doppler flow detectors that use the Doppler effect on waves scattered from moving blood have provided useful information when directed by hand to trace the circulation of animals and man. By scanning with a highly directive flow detector, the areas of flow can be localized. Images can be formed of the interior of blood vessels. These images have the appearance of arteriograms and venograms made by dye contrast radiography, but have none of its hazards. The resolution appears adequate for useful images.
Retrograde Axonal Transport in the Central Nervous System
Authors: LaVail Jennifer H. , LaVail Matthew M.
Published: October 2006

When horseradish peroxidase is injected into the optic tectum of a chick, axons of ganglion cells transport it centripetally to their cell bodies in the retina at a rate of about 72 millimeters per day. After intraocular injections in the young chick, the peroxidase is transported centripetally along efferent axons, and is concentrated in cell bodies within the isthmo-optic nucleus. This retrograde movement of protein from axon terminal to cell body suggests a possible mechanism by which neurons respond to their target areas.
Characterization of a Cofactor That Regulates Dimerization of a Mammalian Homeodomain Protein
Authors: Mendel Dirk B. , Khavari Paul A. , Conley Pamela B. , Graves Mary K. , Hansen Linda P. , Admon Arie , Crabtree Gerald R.
Published: October 2006

Dimerization among transcription factors has become a recurrent theme in the regulation of eukaryotic gene expression. Hepatocyte nuclear factor-1α (HNF-1α) is a homeodomain-containing protein that functions as a dimer. A dimerization cofactor of HNF-1α (DCoH) was identified that displayed a restricted tissue distribution and did not bind to DNA, but, rather, selectively stabilized HNF-1 alpha dimers. The formation of a stable tetrameric DCoH-HNF-1 alpha complex, which required the dimerization domain of HNF-1 alpha, did not change the DNA binding characteristics of HNF-1 alpha, but enhanced its transcriptional activity. However, DCoH did not confer transcriptional activation to the GAL4 DNA binding domain. These results indicate that DCoH regulates formation of transcriptionally active tetrameric complexes and may contribute to the developmental specificity of the complex.