bluuebunny/crossref_metadata_2025 huggingface dataset:
Facilitation of Spindle-Burst Sleep by Conditioning of Electroencephalographic Activity While Awake
Authors: Sterman Maurice B. , Howe Richard C. , Macdonald Lorraine R.
Published: October 2006

A slow-wave electroencephalographic rhythm recorded from the sensorimotor cortex of the waking cat has been correlated behaviorally with the suppression of movement. Facilitation of this rhythm through conditioning selectively enhances a similar pattern recorded during sleep, the familiar spindle burst. The training also produced longer epochs of undisturbed sleep. The specific neural mechanism manipulated during wakefulness appears to function also in sleep and to be involved with the regulation of phasic motor behavior.
Direct Molecular Identification of the Mouse Pink-Eyed Unstable Mutation by Genome Scanning
Authors: Brilliant Murray H. , Gondo Yoichi , Eicher Eva M.
Published: October 2006

DNA sequences associated with the mouse pink-eyed unstable mutation were identified in the absence of closely linked molecular markers and without prior knowledge of the encoded gene product. This was accomplished by "genome scanning," a technique in which high-resolution Southern blots of genomic DNAs were hybridized to a dispersed and moderately repetitive DNA sequence. In this assay, pink-eyed unstable DNA was distinguished from the DNA of wild-type and revertant mice by enhanced hybridization to one of several hundred resolved fragments. The fragment showing enhanced hybridization in pink-eyed unstable DNA was cloned and found to lie within a DNA duplication that is located close to, or within, the pink-eyed dilution locus. The duplication associated with the mouse pink-eyed unstable mutation may mediate the high reversion frequency characteristic of this mutation.
Alarm Response of
Diadema antillarum
Authors: Snyder Noel , Snyder Helen
Published: October 2006

Diadema antillarum
possesses a sensitive escape response to juices of crushed conspecific sea urchins. Stimulation usually results in urchins moving rapidly downcurrent. Strong species specificity of the response suggests that it is an adaptation to reduce predation.
Diadema antillarum
also responds with a running response to contact with
Cassis tuberosa
, a known predator.
Ochratoxin A: Inhibition of Mitochondrial Respiration
Authors: Moore Jack H. , Truelove Bryan
Published: October 2006

Ochratoxin A is a fungal metabolite which induces pathological changes in animals. The toxin was isolated from cultures of
Aspergillus ochraceus
and purified by thin-layer chromatography. Ochratoxin A and one of its hydrolysis products, dihydroisocoumarin, severely inhibited coupled respiration when applied at low concentration to rat liver mitochondria.
Production of Urinary Bladder Carcinomas in Mice by Sodium Saccharin
Authors: Bryan George T. , Ertürk Erdoğan , Yoshida Osamu
Published: October 2006

Pellets weighing 20 to 24 milligrams and containing 20 percent sodium saccharin suspended in cholesterol were surgically implanted into the urinary bladder lumens of female Swiss mice (60 to 90 days old) under ether anesthesia. Incidences of mouse bladder carcinomas in animals exposed to these pellets were 47 and 52 percent as compared with incidences of 13 and 12 percent in control mice exposed to pellets of pure cholesterol. The exposure of the mouse bladder to saccharin was very brief, because the time required for 50 percent of the compound to be eluted from the pellets was about 5.5 hours.
Properties and Composition of Lunar Materials: Earth Analogies
Authors: Schreiber Edward , Anderson Orson L.
Published: October 2006

The sound velocity data for the lunar rocks were compared to numerous terrestrial rock types and were found to deviate widely from them. A group of terrestrial materials were found which have velocities comparable to those of the lunar rocks, but they do obey velocity-density relations proposed for earth rocks.
Modulation of the Time Course of Fast EPSCs and Glutamate Channel Kinetics by Aniracetam
Authors: Tang Cha-Min , Shi Qing-Yao , Katchman Alex , Lynch Gary
Published: October 2006

It is generally accepted that glutamate serves as the neurotransmitter at most excitatory synapses in the mammalian central nervous system (CNS). Synaptic release of glutamate may trigger a fast and a slow excitatory postsynaptic current (EPSC). The slow EPSC is mediated by N-methyl-D-aspartate (NMDA) receptor channels, whereas the fast EPSC is mediated by non-NMDA receptor channels. The nootropic agent aniracetam selectively and reversibly slows the desensitization kinetics of non-NMDA channels and lengthens their single-channel open times. Aniracetam also modulates the kinetics of the fast EPSC in a manner that mirrors its action on the kinetics of the non-NMDA channels. These results support the hypothesis that the properties of the non-NMDA glutamate channels rather than the rate of neurotransmitter clearance are the primary determinants of the kinetics of the fast EPSC in the mammalian CNS.
Selective Destruction of Target Cells by Diphtheria Toxin Conjugated to Antibody Directed against Antigens on the Cells
Authors: Moolten Frederick L. , Cooperband Sidney R.
Published: October 2006

Monkey-kidney cells bearing new surface antigens induced by infection with mumps virus were lysed selectively by diphtheria toxin conjugated to antibody against mumps antigens.
Electrophysiological Evidence for Binocular Disparity Detectors in Human Visual System
Authors: Fiorentini Adriana , Maffei Lamberto
Published: October 2006

Evoked potentials have been recorded from humans in response to two moving gratings presented stereoscopically to both eyes. The amplitude of the evoked potential is greater when the two gratings have slightly different spatial frequencies, which produces an apparent inclination of the binocularly fused image. The amplitude of the response is correlated with the degree of the perceived inclination.
Charge-Mosaic Membranes: Dialytic Separation of Electrolytes from Nonelectrolytes and Amino Acids
Authors: Weinstein John N. , Caplan S. Roy
Published: October 2006

Charge-mosaic membranes were used for dialytic separations of potassium chloride from low-molecular-weight nonelectrolytes and neutral amino acids. The permeability ratio (potassium chloride to uncharged species) ranged from about 6 in the case of methanol to about 86 in that of mannitol. A theoretical model predicts that optimum rates of dialysis should be achieved by dialyzing against salt concentrations other than zero; this prediction was confirmed by experiment. These observations suggest potential applications of mosaics in laboratory separations, industrial processing, and hemodialysis.
Visualization of Bacterial Genes in Action
Authors: Miller O. L. , Hamkalo Barbara A. , Thomas C. A.
Published: October 2006

The morphology of active structural and putative ribosomal RNA genes was observed by electron microscopy after lysis of fragile
Escherichia coli
cells. Conclusions drawn are: most of the chromosome is not genetically active at any one instant; translation is completely coupled with transcription; the 16
S
and 23
S
ribosomal RNA cistrons occur in tandem, in regions which are widely spaced on the chromosome.
LSD: No Teratogenic Action in Rats, Mice, and Hamsters
Authors: Roux C. , Dupuis R. , Aubry M.
Published: October 2006

Lysergic acid diethylamide tartrate was given to 98 pregnant rats, 67 mice, and 22 hamsters as a single dose of 5 to 500 micrograms per kilogram of body weight per day either at the beginning of gestation or during the period of organogenesis. Examination of the 1003 rat fetuses, 521 mouse fetuses, and 189 hamster fetuses obtained failed to prove any abortifacient, teratogenic, or growth-depressing effects.
Pulmonary Surfactant and Evolution of the Lungs
Authors: Clements John A. , Nellenbogen Jean , Trahan Harold J.
Published: October 2006

Pulmonary surfactant has been looked for and found in 11 representatives of four vertebrate classes. The amount of surfactant, estimated by quantitative spreading as a surface film, correlates well with alveolar surface area and with the amount of saturated, mainly dipalmitoyl, phosphatidylcholine in the lung parenchyma. The quantities of other phospholipids do not correlate well with alveolar surface area.
Apollo 12 Magnetometer: Measurement of a Steady Magnetic Field on the Surface of the Moon
Authors: Dyal Palmer , Parkin Curtis W. , Sonett Charles P.
Published: October 2006

The Apollo 12 magnetometer has measured a steady magnetic field of 36 ± 5 gammas on the lunar surface. Surface gradient measurements and data from a lunar orbiting satellite indicate that this steady field is localized rather than global in its extent. These data suggest that the source is a large, magnetized body which acquired a field during an epoch in which the inducing field was much stronger than any that presently exists at the moon.
Pathways through Networks of Branched DNA
Authors: Smithies O.
Published: October 2006

Differentiation may be controlled by forks in DNA each having a replicatable protein "switch," stable in either a "left" or a "right" configuration, which determines the path through the DNA network taken by RNA polymerases during transcription. The possibility for dedifferentiation exists, but differentiation could be made irreversible by the exertion of a similar control over parts of the paths through the network taken by DNA polymerases. The concept of bistable switches at DNA branch points can be used to account for antibody variability.
Cluster Analysis and Multidimensional Scaling of Archeological Sites in Northern Chile
Authors: True D. L. , Matson R. G.
Published: October 2006

Cluster analysis and multidimensional scaling procedures are used to test Chilean site relationships derived by traditional archeological methodologies. The results tend to confirm the intuitive evaluations but clearly indicate the value of computerized statistical analyses for this kind of comparative study.
Potent Sex Attractant of the Gypsy Moth: Its Isolation, Identification, and Synthesis
Authors: Bierl Barbara A. , Beroza Morton , Collier C. W.
Published: October 2006

The sex attractant emitted by the female gypsy moth has been identified as
cis-
7,8-epoxy-2-methyloctadecane. The structure was verified by spectral, gas chromatographic, and biological comparisons with the synthesized compound. Nine closely related isomers were considerably less effective.
Histamine Production by Transplantable Argyrophilic Gastric Carcinoid of
Praomys (Mastomys) natalensis
Authors: Hosoda Syun , Nakamura Wataru , Snell Katharine C. , Stewart Harold L.
Published: October 2006

A transplantable argyrophilic gastric carcinoid of
Praomys (Mastomys) natalensis
contained appreciable amounts of histamine. Dialyzed, microsome-free supernatant of tumor tissue produced definite amounts of histamine in the presence of L-histidine and pyridoxal phosphate. These findings may relate to hypersecretion of gastric acid and formation of multiple ulcers in the stomach and duodenum of
Mastomys
bearing carcinoids.
Localization of 5
S
RNA Genes on
Drosophila
Chromosomes by RNA-DNA Hybridization
Authors: Wimber D. E. , Steffensen D. M.
Published: October 2006

[
3
H]RNA with a high specific activity was prepared from larvae of
Drosophila melanogaster
grown 4 days in contact with [
3
H]uridine. Purified tritiated 5
S
RNA was annealed to the DNA of polytene chromosomes, which had been denatured in formamide. The 5
S
RNA genes are placed within the region 56E-F of the right arm of chromosome 2. This localization was determined from autoradiographs, where the radioactivity from hybrids of [
3
H]RNA and DNA was confined to the 56E-F segment.
Environmental Protection in the City of New York
Authors: Eisenbud Merril
Published: October 2006

Before ending this account of the status of environmental protection in the nation's largest city, some additional thoughts may be desirable.
A High-Pressure Polymorph of Troilite, FeS
Authors: Taylor L. A. , Mao H. K.
Published: October 2006

A new polymorph of FeS was produced in a diamond-anvil cell and observed at high pressure both optically and by x-ray diffraction. Fourteen x-ray reflections of the high-pressure FeS were recorded; however, the crystal structure is unknown. This form of FeS is stable at 25°C only at pressures above approximately 55 kilobars. The transition to the lower pressure polymorph, troilite, is rapid and reversible.
Brain Evolution: New Light on Old Principles
Authors: Jerison Harry J.
Published: October 2006

The fossil evidence on the evolution of brains and bodies in mammals shows that there has been a progressive increase in relative brain size accompanied by and correlated with increased diversity among species in relative brain size. Small-brained species have also evolved, but more large-brained species have appeared in successive epochs.
Mars: Detection of Atmospheric Water Vapor during the Southern Hemisphere Spring and Summer Season
Authors: Barker Edwin S. , Schorn Ronald A. , Woszczyk Andrzej , Tull Robert G. , Little Stephen J.
Published: October 2006

Water vapor was found to reappear in the atmosphere of Mars during its southern hemisphere spring and summer season, with a maximum vertical column abundance of 45 to 50 microns of precipitable water averaged over the entire planet. Although the spring-summer seasons for each hemisphere are generally symmetrical with respect to the appearance of water vapor, the data suggest that water vapor may appear later in the season and in slightly larger amounts during the southern hemisphere spring-summer.
Molecular Microscopy: Fundamental Limitations
Authors: Breedlove J. R. , Trammell G. T.
Published: October 2006

On the basis of estimates of molecular damage caused by the observation process, it is concluded that molecular microscopy of biological molecules in which the individual atoms are resolved is impossible with an electron or x-ray microscope. Microscopes that use low-energy helium atoms or neutrons as illuminants may be capable of serving as ultimate biomolecular microscopes.
Increase of the Catalytic Activity of Phospholipase C-γ1 by Tyrosine Phosphorylation
Authors: Nishibe Shunzo , Wahl Matthew I. , Hernandez-Sotomayor S. M. , Tonks Nicholas K. , Rhee Sue Goo , Carpenter Graham
Published: October 2006

Phospholipase C-γ1 (PLC-γ1), an isozyme of the phosphoinositide-specific phospholipase C family, which occupies a central role in hormonal signal transduction pathways, is an excellent substrate for the epidermal growth factor (EGF) receptor tyrosine kinase. Epidermal growth factor elicits tyrosine phosphorylation of PLC-γ1 and phosphatidylinositol 4,5-bisphosphate hydrolysis in various cell lines. The ability of tyrosine phosphorylation to activate the catalytic activity of PLC-γ1 was tested. Tyrosine phosphorylation in intact cells or in vitro increased the catalytic activity of PLC-γ1. Also, treatment of EGF-activated PLC-γ1 with a tyrosine-specific phosphatase substantially decreased the catalytic activity of PLC-γ1. These results suggest that the EGF-stimulated formation of inositol 1,4,5-trisphosphate and diacylglycerol in intact cells results, at least in part, from catalytic activation of PLC-γ1 through tyrosine phosphorylation.
ELAM-1 Mediates Cell Adhesion by Recognition of a Carbohydrate Ligand, Sialyl-Le
x
Authors: Phillips M. Laurie , Nudelman Edward , Gaeta Federico C. A. , Perez Mary , Singhal Anil K. , Hakomori Sen-Itiroh , Paulson James C.
Published: October 2006

Recruitment of neutrophils to sites of inflammation is mediated in part by endothelial leukocyte adhesion molecule-1 (ELAM-1), which is expressed on activated endothelial cells of the blood vessel walls. ELAM-1 is a member of the LEC-CAM or selectin family of adhesion molecules that contain a lectin motif thought to recognize carbohydrate ligands. In this report, cell adhesion by ELAM-1 is shown to be mediated by a carbohydrate ligand, sialyl-Lewis X (SLe
x
; NeuAcα2,3Galβ 1,4(Fucα1,3)-GlcNAc-), a terminal structure found on cell-surface glycoprotein and glycolipid carbohydrate groups of neutrophils.
Complementation of the Mitotic Activator, p80

cdc25

, by a Human Protein-tyrosine Phosphatase
Authors: Gould Kathleen L. , Moreno Sergio , Tonks Nicholas K. , Nurse Paul
Published: October 2006

The onset of M phase requires the activation of the pp34 protein kinase in all eukaryotes thus far examined. In
Schizosaccharomyces pombe
, pp34 is phosphorylated on Tyr
15
, and dephosphorylation of this residue regulates the initiation of mitosis. In this study, it is shown that dephosphorylation of Tyr
15
triggered activation of the pp34-cyclin complex from fission yeast, that a human protein-tyrosine phosphatase can catalyze this event both in vitro and in vivo, and that activation of fission yeast pp34 does not require threonine dephosphorylation. The complementary DNA that encoded the tyrosine phosphatase replaced the mitotic activator p80

cdc25

, closely associating the
cdc25
+
-activating pathway with tyrosine dephosphorylation of pp34.
Solution Structure of FKBP, a Rotamase Enzyme and Receptor for FK506 and Rapamycin
Authors: Michnick Stephen W. , Rosen Michael K. , Wandless Thomas J. , Karplus Martin , Schreiber Stuart L.
Published: October 2006

Immunophilins, when complexed to immunosuppressive ligands, appear to inhibit signal transduction pathways that result in exocytosis and transcription. The solution structure of one of these, the human FK506 and rapamycin binding protein (FKBP), has been determined by nuclear magnetic resonance (NMR). FKBP has a previously unobserved antiparallel β-sheet folding topology that results in a novel loop crossing and produces a large cavity lined by a conserved array of aromatic residues; this cavity serves as the rotamase active site and drug-binding pocket. There are other significant structural features (such as a protruding positively charged loop and an apparently flexible loop) that may be involved in the biological activity of FKBP.
Superior Colliculus Cell Responses Related to Eye Movements in Awake Monkeys
Authors: Wurtz Robert H. , Goldberg Michael E.
Published: October 2006

Single cell responses were recorded from the superior colliculus of awake monkeys trained to move their eyes. A class of cells that discharged before eye movements was found in the intermediate and deep layers of the colliculus. The response of the cells was most vigorous before saccadic eye movements within a particular range of directions. These cells had no visual receptive fields, and visually guided eye movements were not necessary for their discharge, since they responded in total darkness before spontaneous eye movements and vestibular nystagmus.
Supraoptic Neurosecretory Cells: Autonomic Modulation
Authors: Barker Jeffery L. , Crayton John W. , Nicoll Roger A.
Published: October 2006

Neurosecretory cells in the supraoptic nuclei of anesthetized cats were antidromically identified by electrical stimulation of the posterior pituitary. The responses of these units to afferent volleys from vagal and carotid sinus nerves were examined with a computer of average transients. Synaptic excitation of neurosecretory cells by stimulation of these pathways demonstrates the existence of excitatory inputs from vagal and carotid sinus nerve afferents. Since these pathways are involved in the release of antidiuretic hormone, the results support the hypothesis that its release is related to an increase in discharge frequency of supraoptic neurosecretory cells.
Xenon Hexafluoride: Structural Crystallography of Tetrameric Phases
Authors: Burbank R. D. , Jones G. R.
Published: October 2006

Three crystalline phases of xenon hexafluoride are based on tetrameric association of XeF
5
+
and F
-
ions into eight-membered rings. Phase I (monoclinic, 8 XeF
6
units per cell) transforms at ∼10°C to phase II (orthorhombic, 16 XeF
6
units per cell), which in turn transforms at ∼ -25°C to phase III (monoclinic, 64 XeF
6
units per doubly primitive cell). The transformation from phase I to phase II requires gross reorientation of half of the tetramers in the structure. The transformation from phase II to phase III involves only an ordering of right-handed and left-handed configurations.
Contours and Contrast: Responses of Monkey Lateral Geniculate Nucleus Cells to Luminance and Color Figures
Authors: De Valois Russell L. , Pease Paul L.
Published: October 2006

The responses of single units in the monkey lateral geniculate nucleus to different portions of figures which differed from their backgrounds in color and brightness were examined. Border enhancement was found in the response to luminance figures but not in the response to color figures. In addition, cells showed border enhancement only in the case of a figure which produced an increment (as opposed to a decrement) in their firing rates. In situations in which very striking brightness contrast is seen perceptually, the cells do not show the corresponding changes in firing rate across the whole pattern. The lateral inhibitory mechanisms found in the retina and geniculate can thus account for luminance border enhancement, but not entirely for simultaneous brightness or color contrast, for which other cortical processes of some sort must be responsible.
p
-Nitrophenyl Phosphate Hydrolysis and Calcium Ion Transport in Fragmented Sarcoplasmic Reticulum
Authors: inesi Giuseppe
Published: October 2006

The calcium ion pump of fragmented sarcoplasmic reticulum can be coupled to hydrolysis of
p
-nitrophenyl phosphate, in the absence of added adenosine triphosphate. Comparison of the activities obtained with the two substrates suggests an analogous mechanism of transport. Independent of the substrate, a 2 : 1 ratio between calcium ion transport and substrate hydrolysis is displayed by the system, and an identical amount of work is required for ion transport against a given gradient. A phosphate ester appears necessary for substrate utilization in the pump mechanism, whereas the structure of the substrate determines the rates of activity and the affinity of the system for calcium ion.
Oligoclonal Expansion and CD1 Recognition by Human Intestinal Intraepithelial Lymphocytes
Authors: Balk Steven P. , Ebert Ellen C. , Blumenthal Robin L. , McDermott Francis V. , Wucherpfennig Kai W. , Landau Steven B. , Blumberg Richard S.
Published: October 2006

A human intestinal intraepithelial lymphocyte (IEL) T cell line was established from jejunum to characterize the structure and function of the αβ T cell antigen receptors (TCRs) expressed by this population. Single-sided polymerase chain reaction (PCR) amplification cloning and quantitative PCR amplification of the TCR chains from the cell line and from fresh IELs demonstrated that IELs were oligoclonal. The IEL T cell line exhibited CD1-specific cytotoxicity and a dominant IEL T cell clone was CD1c-specific. Thus, human jejunal intraepithelial lymphocytes are oligoclonal and recognize members of the CD1 gene family.
Neutralization of Divergent HIV-1 Isolates by Conformation-Dependent Human Antibodies to Gp120
Authors: Steimer Kathelyn S. , Scandella Carl J. , Skiles Paul V. , Haigwood Nancy L.
Published: October 2006

The spectrum of human immunodeficiency virus type 1 (HIV-1) isolates neutralized by antibodies from HIV-1-infected humans is broader than the spectrum of isolates neutralized by sera from animals immunized with purified gp120 subunits. This broader neutralization was due, in part, to the presence of antibodies to conserved gp120 conformational epitopes. Purified conformation-dependent gp120-specific human antibodies neutralized a wider range of virus isolates than human antibodies directed to linear determinants in gp120 and were also responsible for the majority of the gp120-specific CD4-blocking activity of HIV-1-infected human sera. A gp120 subunit vaccine that effectively presents these conformation-dependent neutralization epitopes should protect against a broader range of HIV-1 variants than a vaccine that presents exclusively linear determinants.
Primary Structure And Functional Expression of the 5HT
3
Receptor, A Serotonin-gated Ion Channel
Authors: Maricq Andres V. , Peterson Andrew S. , Brake Anthony J. , Myers Richard M. , Julius David
Published: October 2006

The neurotransmitter serotonin (5HT) activates a variety of second messenger signaling systems and through them indirectly regulates the function of ion channels. Serotonin also activates ion channels directly, suggesting that it may also mediate rapid, excitatory responses. A complementary DNA clone containing the coding sequence of one of these rapidly responding channels, a 5HT
3
subtype of the serotonin receptor, has been isolated by screening a neuroblastoma expression library for functional expression of serotonin-gated currents in
Xenopus
oocytes. The predicted protein product has many of the features shared by other members of the ligand-gated ion channel family. The pharmacological and electrophysiological characteristics of the cloned receptor are largely consistent with the properties of native 5HT
3
receptors. Messenger RNA encoding this receptor is found in the brain, spinal cord, and heart. This receptor defines a new class of excitatory ligand-gated channels.
Phosphorylation of c-Src on Tyrosine 527 by Another Protein Tyrosine Kinase
Authors: Thomas J. E. , Soriano P. , Brugge J. S.
Published: October 2006

The protein tyrosine kinase activity of the cellular Src protein is negatively regulated by phosphorylation at tyrosine residue 527 (Tyr
527
). It has not been established whether this regulatory modification of Src is mediated by autophosphorylation or by another cellular protein kinase. The phosphorylation of a modified form of c-Src that lacks kinase activity was examined in mouse cells that do not express endogenous Src (because of the targeted disruption of both
src
alleles). Phosphorylation of the inactive form of Src on Tyr
527
occurred to a similar extent in cells lacking endogenous Src as it did in cells expressing Src. Therefore, Tyr
527
phosphorylation, and thus negative control of Src kinase activity, is mediated by another cellular protein tyrosine kinase.
Tay-Sachs Disease: Prenatal Diagnosis
Authors: O'Brien John S. , Okada Shintaro , Fillerup Dorothy L. , Veath M. Lois , Adornato Bruce , Brenner Paul H. , Leroy Jules G.
Published: October 2006

Fifteen pregnant women with a 25 percent risk of delivering a child with Tay-Sachs disease were monitored by amniocentesis and hexosaminidase A assays of amniotic fluid, uncultured amniotic cells, and cultured amniotic cells. Tay-Sachs disease was diagnosed prenatally in six fetuses; the diagnosis was confirmed in one child after birth and in five fetuses after therapeutic abortion. Prenatal diagnosis indicated the absence of Tay-Sachs disease in nine other fetuses; this diagnosis was confirmed postnatally in six, three are still in utero.
Irreversible Effects of Visible Light on the Retina: Role of Vitamin A
Authors: Noell W. K. , Albrecht R.
Published: October 2006

Diffuse retinal irradiation by visible light produces in the rat the death of visual cells and pigment epithelium. Typically, cage illumination of 1500 lux from fluorescent light through a green filter leads to severe damage when continued for 40 hours. Vitamin A deficiency protects against this damage but experiments show that retinol released by light from rhodopsin is probably not the toxic agent. Protection against light damage depends on a long-range state of cell adaptation to light itself. The normal diurnal cycle of light and dark seems to be the essential factor in controlling visual cell viability and susceptibility.
Retrograde Amnesia: Electroconvulsive Shock Effects after Termination of Rapid Eye Movement Sleep Deprivation
Authors: Fishbein William , McGaugh James L. , Swarz Jeffrey R.
Published: October 2006

Mice that were deprived of rapid eye movement sleep for 2 days immediately after one-trial training in an inhibitory avoidance task and were given an electroconvulsive shock after deprivation displayed retrograde amnesia on a retention test given 24 hours later. Electroconvulsive shock produced no amnesia in comparable groups of animals that were not deprived of rapid eye movement sleep.
Aplysia californica
: Analysis of Nuclear DNA in Individual Nuclei of Giant Neurons
Authors: Lasek Raymond J. , Dower William J.
Published: October 2006

The nuclei of the giant neurons of the marine mollusk
Aplysia californica
can contain more than 0.2 microgram of DNA. This is more than 200,000 times as much DNA as the haploid amount found in
Aplysia
sperm. On the basis of nuclear DNA content, the giant neurons R-2, P-1, and L-6 of adult animals can each be divided into at least two populations. The mean DNA content of these two populations (0.067 and 0.131 microgram of DNA) are approximately related by a factor of 2. This suggests that much and perhaps all of the genome replicates repeatedly (up to 16 times) during the growth and development of these neurons and that each replication is synchronous. The enormous amount of DNA in these cells opens up the possibility of characterizing the DNA and other constituents of chromatin from individual but phenotypically different neurons.
Alcohol Dependence Produced in Mice by Inhalation of Ethanol: Grading the Withdrawal Reaction
Authors: Goldstein Dora B. , Pal Nandita
Published: October 2006

Intoxicating blood levels of ethanol are maintained for several days in mice housed in an atmosphere of ethanol vapor. On removal from the alcohol, all the mice develop withdrawal signs. The signs can be graded to indicate the time course and intensity of the withdrawal reaction.
Bispectrum Analysis of Electroencephalogram Signals during Waking and Sleeping
Authors: Barnett T. P. , Johnson L. C. , Naitoh P. , Hicks N. , Nute C.
Published: October 2006

The degree of interaction of component waves making up a single electroencephalogram trace was strongly correlated with alpha activity, lead placement, and state of consciousness. Significant quadratic coupling of the waves was found only for awake subjects with high alpha activity. For these subjects about 50 percent of beta activity can be attributed to harmonic coupling with the alpha peak. During sleep, the degree of interaction was of borderline significance and did not follow a consistent pattern with respect to subject, frequency, state, or lead.
A Male-Producing Strain of the House Fly
Authors: McDonald Ian C.
Published: October 2006

An autosome inherited by male offspring only and a temperature-sensitive lethal factor have been combined in a house fly strain which produces both male and female progeny when reared at 25.6°C but only male progeny when reared at 33.3°C.
Immune Response Restoration with Macrophage Culture Supernatants
Authors: Hoffmann M. , Dutton R. W.
Published: October 2006

Depression of the in vitro immune response of mouse spleen cell suspensions to sheep erythrocytes by removal of macrophages can be reversed by the addition of supernatants from peritoneal macrophage cultures. Supernatant activity can be absorbed by the red cell antigen, and supernatant-treated red cells are stimulatory in the absence of macrophages or supernatant.
Glycoproteins as Biological Antifreeze Agents in Antarctic Fishes
Authors: Devries Arthur L.
Published: October 2006

The blood serums of Antarctic fishes freeze at -2°C, which is approximately 1°C below the melting points of their serums. This thermal hysteresis is due to the influence of serum glycoproteins. The temperatures of freezing and melting of aqueous solutions of the purified glycoproteins suggest that this thermal hysteresis results from the adsorption of the glycoprotein molecule onto the surface of ice crystals.
Soil: A Natural Sink for Carbon Monoxide
Authors: Inman Robert E. , Ingersoll Royal B. , Levy Elaine A.
Published: October 2006

A potting soil mixture depleted carbon monoxide in a test atmosphere from a concentration of 120 parts per million to near zero within 3 hours. Maximum activity occurred at 30°C. Steam sterilization of the soil, the addition of antibiotics or 10 percent (by weight) saline solution, and anaerobic conditions all prevented carbon monoxide uptake. Sterilized soil inoculated with nonsterile soil acquired activity with time. Samples of various natural soils differed in their ability to remove carbon monoxide from the air. Acidic soils with a high content of organic matter were generally the most active. The soil's ability to remove carbon monoxide from the atmosphere is ascribed to the activity of soil microorganisms.
Holography
Authors: Gabor Dennis , Kock Winston E. , Stroke George W.
Published: October 2006

Research on holography has now grown to such dimensions that we have not been able to mention each of the numerous authors who have made significant contributions to it. Investigators from Bell Telephone Laboratories, the RCA, Xerox, and Westinghouse laboratories, Conductron Corporation, GC-Optronics, IBM, TRW Systems, the University of Michigan, and Stanford University have made particularly significant early contributions in the United States. Especially notable were the efforts of R. J. Collier, L. Lin, K. S. Pennington, D. Ansley, L. Siebert, R. M. Grant, A. Lohmann, R. F. Wuerker, K. Stetson, R. Powell, J. Goodman, and their co-workers, in addition to those already mentioned, among many others. Early work in many parts of the world also includes that in France by S. Lowenthal, G. Nomarski, and J. Viénot; in Germany by H. Nassenstein; in Great Britain by J. M. Burch; in Japan by J. Tsujiuchi and T. Tsuruta; and in the Soviet Union by Yu. Y. N. Denisyuk, I. Nalimov, and L. M. Soroko. For a fuller account of these developments, see (42) and other references.
Polyester Fiber: From Its Invention to Its Present Position
Authors: Brown Alfred E. , Reinhart Kenneth A.
Published: October 2006

The use of polyester fibers has grown more rapidly than that of any other man-made fiber. Many factors have contributed to this growth. Polyester's unique physical properties of strength, high modulus, elasticity, and durability are the basis for its success. The tailorability of the fiber makes it possible to generate a whole family of property variants for a wide variety of end uses. The ready availability and low cost of the raw materials, the continuing advances in polymerization technology, and the versatility of the melt spinning process have also been major factors in establishing polyester as the leading man-made fiber.

New end uses have had a major impact on the growth of polyester. Most notable was the introduction of durable press fabrics for clothing and home furnishings. The consumer preference for easy-care fabrics and garments makes the durable press area one of continuing growth. Two relatively new areas where growth is expected to continue at a rapid rate are tire cord and textured knits for women's and men's outerwear.
Rowing: A Similarity Analysis
Authors: McMahon Thomas A.
Published: October 2006

The theory of models is employed for calculating the speed of geometrically similar racing shells. The theoretical prediction, that shells should have a speed proportional to the number of oarsmen raised to the 1/9 power, is in excellent agreement with observations. A significant implication for the proportions of lightweight and heavyweight eight-oared shells, indicating how both might attain the same speed, is developed.
Eye-Head Coordination in Monkeys: Evidence for Centrally Patterned Organization
Authors: Bizzi Emilio , Kalil Ronald E. , Tagliasco Vincenzo
Published: October 2006

Eye-head coordination was investigated by recording from the neck and eye muscles in monkeys. The results show that (i) during eye-head turning, neural activity reaches the neck muscles before the eye muscles, and (ii) all agonist neck muscles are activated simultaneously regardless of the initial head position. Since overt movement of the eyes precedes that of the head, it was concluded that the central neural command initiates the eye-head sequence but does not specify its serial order. Furthermore, it was determined that the compensatory eye movement is not initiated centrally but instead is dependent upon reflex activation arising from movement of the head.
DDT: Disrupted Osmoregulatory Events in the Intestine of the Eel
Anguilla rostrata
Adapted to Seawater
Authors: Janicki Ralph H. , Kinter William B.
Published: October 2006

The drinking of seawater and absorption of water along with sodium across the intestinal epithelium are well-known osmoregulatory events in marine teleosts. The insecticide DDT impairs fluid absorption in intestinal sacs from eels adapted to seawater. Furthermore, this functional impairment has an enzymatic basis; DDT also inhibits the (Na
+
and K
+
) activated, Mg
2+
-dependent adenosine triphosphatase in homogenates of the intestinal mucosa. Thus, the extreme sensitivity of teleosts to organochlorine pollutants may involve the disruption of osmoregulatory transport mechanisms.
GnRH-Induced Ca
2+
Oscillations and Rhythmic Hyperpolarizations of Pituitary Gonadotropes
Authors: Tse Amy , Hille Bertil
Published: October 2006

Secretion of gonadotropic hormones from pituitary gonadotropes in response to gonadotropin-releasing hormone (GnRH) is essential for regulation of reproductive potential. Gonadotropes from male rats exhibited an unusual form of cellular excitation that resulted from periodic membrane hyperpolarization. GnRH induced an oscillatory release of intracellular Ca
2+
via a guanosine triphosphate (GTP) binding protein-coupled phosphoinositide pathway and hyperpolarized the gonadotrope periodically by opening apamin-sensitive Ca
2+
-activated K
+
(SK) channels. Each hyperpolarization was terminated by firing of a few action potentials that may result from removal of inactivation from voltage-gated Na
+
and Ca
2+
channels.
Duricrusts and Deep-Weathering Profiles in Southwestern Wisconsin
Authors: Dury G. H. , Knox J. C.
Published: October 2006

Numerous exposures in southwestern Wisconsin display the profiles of relict deep weathering. Crusts are mainly siliceous, but many are ferruginized to some extent. The occurrence of blocky silcrete, thought to be reported for the first time, recalls the profiles in the Australian belt of transition from silcrust to ferricrust. The humid-tropical kind of pedogenesis necessary to effect this transition may have operated as late as the mid-Miocene. In some localities, the action of groundwater has caused crusting, mottling, and reduction beneath the dolomite of former tower karst.
Extremely Rapid Visual Search: The Maximum Rate of Scanning Letters for the Presence of a Numeral
Authors: Sperling George , Budiansky Judy , Spivak Jerry G. , Johnson Martha C.
Published: October 2006

Subjects searched a rapid sequence of computer-produced letter arrays for the presence of a numeral in one of the arrays. The subjects' scanning rates were computed from their percentage of correct detections of the location of the numeral. Scanning rates were very high and approximately the same for a wide variety of conditions; the highest scanning rates (125 and 75 letters per second for two subjects) occurred when there were 9 or 16 letters in each of the arrays and when new arrays were presented every 40 to 50 milliseconds. Giving the subject advance knowledge of the numeral to be presented made little difference in the scores.
Molecular Structure of Starch-Type Polysaccharides from
Hericium ramosum
and
Hericium coralloides
Authors: McCracken D. A. , Dodd J. L.
Published: October 2006

Starch isolated from the fungi
Hericium ramosum
and
Hericium
coralloides differs from that of higher plants in that it consists only of short-chain amylose molecules (32 to 45 glucose units long).
The Periplasmic Galactose Binding Protein of
Escherichia coli
Authors: Kalckar Herman M.
Published: October 2006

A specific high affinity galactose transport system called P
βg
can be induced by trace amounts of galactose in the medium by virtue of its own ability to capture and accumulate galactose. The transport system is coregulated with the production of a high affinity periplasmic galactose binding protein, which constitutes but one part of the transport system. Some transport negative mutants still remain producers of this binding protein.

A close correlation exists between production of the active binding protein and the presence of galactose chemotaxis. The hypothesis, that this binding protein is a common element of the specific galactose transport system, P
βg
, and of galactose chemotaxis is supported by observations on structural mutants, being defective in galactose binding protein as well as showing a lack of galactose chemotaxis. The binding protein is a monomer with two binding sites for galactose. Binding of one or two of the galactose molecules elicits specific conformational changes of the galactose binding protein (lowered affinity for galactose, increase of charges of the protein, increased fluorescence of tryptophan residues). The importance of these features for transport and for chemotaxis is discussed.
The Brain as a Parallel Coherent Detector
Authors: Trehub Arnold
Published: October 2006

Knowledge of the bioelectric signal-to-noise ratios in rat brain makes it possible to demonstrate for the first time that the brain functions as a coherent signal detector, an important class of detectors that are explicitly formulated within the statistical theory of communication. Within an afferent neuronal channel of a single modality, the brain functions as a parallel signal processor.
Stereoscopic Depth Movement: Two Eyes Less Sensitive than One
Authors: Tyler C. William
Published: October 2006

Visual sensitivity to stimuli with sinusoidal movement was examined under a number of conditions of binocular stimulation. Sensitivity to stereoscopic movement in depth was reduced in comparison to that for monocular movement. The reduced sensitivity appeared to be due to the presence of stereoscopic depth movement, as opposed to stereoscopic stimulation, binocular movement, or fusion of the images.
Central and Peripheral Control of Gill Movements in
Aplysia
Authors: Kupfermann I. , Pinsker H. , Castellucci V. , Kandel E. R.
Published: October 2006

Two types of gill contraction in
Aplysia
were used to study the relation of peripheral and central pathways in controlling behavioral responses in a mollusk. A weak or moderate tactile stimulus to the mantle elicits gill contraction (gill-withdrawal reflex) as a component of a more extensive withdrawal response; a stimulus applied directly to the gill elicits a localized response of the gill pinnule (pinnule response). Central pathways through the abdominal ganglion are both necessary and sufficient for the gill-withdrawal reflex, and motor neuron L7 makes direct connections with gill muscles, without engaging the peripheral plexus. Peripheral pathways are necessary and sufficient for the pinnule response. As a result of the independence of peripheral and central pathways, habituation by repeated tactile stimulation of one pathway does not affect the responsiveness of the other pathway.
Prenatal Stress Feminizes and Demasculinizes the Behavior of Males
Authors: Ward Ingeborg L.
Published: October 2006

Male rats were exposed to prenatal or postnatal stress, or both. The prenatally stressed males showed low levels of male copulatory behavior and high rates of female lordotic responding. Postnatal stress had no effect. The modifications are attributed to stress-mediated alterations in the ratio of adrenal to gonadal androgens during critical stages of sexual differentiation. Specifically, it appears that stress causes an increase in the weak adrenal androgen, androstenedione, from the maternal or fetal adrenal cortices, or from both, and a concurrent decrease in the potent gonadal androgen, testosterone.
Variations of the Visual Responses of the Superior Colliculus in Relation to Body Roll
Authors: Bisti S. , Maffei L. , Piccolino M.
Published: October 2006

A large percentage of the directional units of the superior colliculus of the curarized cat modify their response to a particular moving visual stimulus as a function of the position of rotation of the animal about its longitudinal axis.
Inductive Interactions between Human Dermis and Chick Chorionic Epithelium
Authors: Sawyer Roger H. , Abbott Ursula K. , Trelford John D.
Published: October 2006

In a study of specificity in mesenchymal-epithelial interactions, human embryonic dermis has been recombined with chick chorionic epithelium and cultured for 7 days on a host chick chorioallantoic membrane. Dermis from the sole of the foot or palm of the hand induces chick chorionic epithelium to form an epidermis that resembles chick rather than human epidermis. Chick epithelium, though it has the capacity to respond to a human dermal stimulus, is limited to forming chick-type tissue. The human dermis was modified in its turn by culture in combination with chick epithelium.
Apollo 12 Lunar Material: Effects on Lipid Levels of Tobacco Tissue Cultures
Authors: Weete John D. , Walkinshaw Charles H. , Laseter John L.
Published: October 2006

Tobacco tissue cultures grown in contact with lunar material from Apollo 12, for a 12-week period, resulted in fluctuations of both the relative and absolute concentrations of endogenous sterols and fatty acids. The experimental tissues contained higher concentrations of sterols than the controls did. The ratio of campesterol to stigmasterol was greater than 1 in control tissues, but less than 1 in the experimental tissues after 3 weeks. High relative concentrations (17.1 to 22.2 percent) of an unidentified compound or compounds were found only in control tissues that were 3 to 9 weeks of age.
Pressure Blades and Total Cutting Edge: An Experiment in Lithic Technology
Authors: Sheets Payson D. , Muto Guy R.
Published: October 2006

Pressure techniques were used to remove 83 blades from a preformed obsidian core weighing 820 grams, yielding 17.32 meters of acute cutting edge. The blades represented 91 percent of the original weight (2.1 centimeters of acute cutting edge per gram of original material), thus demonstrating the efficiency of the pressure-blade techniques for the production of acute cutting edges.
Preceramic Sequences in the El Abra Rock-Shelters, Colombia
Authors: Hurt Wesley R. , van der Hammen Thomas , Urrego Gonzalo Correal
Published: October 2006

A series of crude stone artifacts, characterized by a trimming mainly of the working edge of a single face of a chert flake or a fragment of a nodule, was excavated in the El Abra rock-shelters, north of Bogotá, Colombia. The tools indicate a cultural complex distinct from others that have been described for the Paleo-Indian of South America.
Chalcocite Oxidation and Coupled Carbon Dioxide Fixation by
Thiobacillus ferrooxidans
Authors: Nielsen Allen M. , Beck Jay V.
Published: October 2006

The reaction of cell suspensions of
Thiobacillus ferrooxidans
with pulverized chalcocite (Cu
2
S) in a Warburg manometric apparatus resulted in oxygen uptake accompanied by increased solubilization of copper and fixation of carbon dioxide. Since the only detectable oxidized products were cupric ions and the more oxidized form of the sulfide mineral, that is, digenite or covellite, the apparent source of energy for the carbon dioxide fixation was provided by the oxidation of the cuprous copper of the chalcocite.
Activities of Sodium and Potassium Ions in Epithelial Cells of Small Intestine
Authors: Lee Chin O. , Armstrong W. McD.
Published: October 2006

Intracellular molar Na
+
activity (
a
Na
), measured with cation-selective glass microelectrodes, in epithelial cells of isolated bullfrog small intestine immersed at 26°C in a sodium sulfate Ringer solution containing mannitol was 0.0144 ± 0.0031 (average value plus or minus standard deviation). The corresponding K
+
activity (
a
K
) was 0.0854 ± 0.0060. Combination of these values with previous estimates of intracellular Na
+
and K
+
concentrations under identical conditions indicated that a substantial fraction of the cellular Na
+
is in an osmotically inactive state. When the cells were exposed to a Ringer solution in which 26 millimoles of mannitol per liter were replaced by 3-
O
-methyl glucose, highly significant decreases in
a
K
and
a
Na
were observed. The decrease in
a
K
was proportionately larger than the corresponding decrease in
a
Na
.