bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibiting Effect of Tobacco Smoke on Some Crystalline Enzymes
Authors: Lange Rolf
Published: October 2006

Tobacco smoke absorbed in phosphate buffer at neutral
p
H inhibits irreversibly the enzymes rabbit muscle glyceraldehyde-3-phosphate dehydrogenase and yeast alcohol dehydrogenase, whereas lactic dehydrogenase and glutamic dehydrogenase are not inhibited. A transient inhibition of beef liver catalase occurs. Indirect evidence suggests that the observed enzyme inhibition is caused by peroxides present in the smoke.
Sulfate-Reducing Bacteria and Pyritic Sediments in Antarctica
Authors: Barghoorn Elso S. , Nichols Robert L.
Published: October 2006

Black lacustrine and marine sediments occur in the McMurdo Sound region of Antarctica. The black color is due to the presence of iron sulfide, precipitated by sulfate-reducing bacteria (
Desulfovibrio
) in the presence of decaying organic matter of algal origin. Viability of sulfate-reducing bacteria in the sediments was demonstrated in the laboratory by culturing in anaerobic liquid media. It is probable that sulfate-reducing bacteria are widely distributed in Antarctica.
Isolation of Abscisin, an Abscission Accelerating Substance
Authors: Liu Wen-Chih , Carns Harry R.
Published: October 2006

A crystalline substance, designated
abscisin,
which accelerates abscission of excised debladed petioles at 10
-2
microgram per abscission zone, has been isolated from cotton burs. The yield was approximately 1 milligram from 10 kilograms of dry plant material.
X-ray Fluorescence Analysis in Biology
Authors: Hall Theodore
Published: October 2006

Our efforts to understand the important biological roles of many "minor" elements are limited by the capabilities of the existing instruments. X-ray fluorescence analysis is not the most sensitive method for the assay of minor elements, but it is the instrumental technique of choice both for certain clinical studies and for certain research problems. The technique will be more widely used as it becomes more widely known.
Persistence of a Photosynthetic Rhythm in Enucleated
Acetabularia
Authors: Sweeney Beatrice M. , Haxo Francis T.
Published: October 2006

The unicellular alga
Acetabularia
was found to show a diurnal rhythm in photosynthesis. This rhythm continued for at least three cycles in constant light and temperature, and hence can be considered endogenous. Plants from which the nucleus had been removed by severing the basal rhizoids showed no modification in the photosynthetic rhythm over a number of cycles. The nucleus is, therefore, not immediately essential for the maintenance of rhythmicity in
Acetabularia
. Conversely, a mechanism for sustaining time-keeping must exist in the cytoplasm.
Functional Effects of Focused Ultrasound on Mammalian Nerves
Authors: Young Robert R. , Henneman Elwood
Published: October 2006

Differential blocking of conduction in mammalian nerve fibers has been produced by irradiation of the whole nerve with focused ultrasound. The smallest (C) fibers are the most sensitive; the largest (A-alpha) fibers are the least vulnerable. Fully reversible blocking can be obtained with carefully graded doses of ultrasound.
Cutaneous Molt Induced by Calciphylaxis in the Rat
Authors: Selye Hans , Gentile G. , Prioreschi P.
Published: October 2006

A molt, conducive to the loss and subsequent replacement of all cutaneous layers, can be induced by topical "calciphylaxis" in the rat. This is accomplished by sensitization with dihydrotachysterol followed by challenge with egg white or ferric dextran.
Sex as Regulator of Triglyceride Metabolism in the Mosquito
Authors: Van Handel Emile , Lum Patrick T. M.
Published: October 2006

The female mosquito, in contrast to the male mosquito or the male and female house fly, synthesizes triglycerides when maintained on glucose; after 7 days, the amount of triglycerides in the female may be 50 times that in the male. Polyunsaturated fatty acids are absent from the newly synthesized triglycerides.
The Influence of Prior Synaptic Activity on the Induction of Long-Term Potentiation
Authors: Huang Yan-You , Colino Asuncion , Selig David K. , Malenka Robert C.
Published: October 2006

Long-term potentiation (LTP) is an extensively studied model of synaptic plasticity, in part because it is a plausible biological correlate for the Hebbian synaptic modification that forms the basis for theoretical models of neural development, learning, and memory. Although these models must incorporate algorithms that constrain synaptic weight changes, physiological evidence for such mechanisms is limited. Examination of LTP in area CA1 of the hippocampus revealed that the threshold for LTP induction was not fixed but could be strongly influenced by the recent history of synaptic activity. This effect was transient, synapse-specific, and dependent on postsynaptic
N
-methyl -D-aspartate (NMDA) receptor activation. These results suggest that the threshold for LTP induction may be continually adjusted according to the recent history of NMDA receptor activation and provide a physiological mechanism by which LTP can be transiently inhibited.
Magnitude Estimation of the Brightness of Brief Foveal Stimuli
Authors: Raab David H.
Published: October 2006

Eighteen observers judged the apparent brightness of light flashes that varied in both duration and luminance. The median numerical estimations (made relative to a standard flash) confirmed three principles: the reciprocity between luminance and duration (Bloch's law), the enhancement of brightness at about 50 milliseconds (Broca-Sulzer effect), and the power-law relation between brightness and energy (Stevens's law).
Carbonaceous "Snowflakes" and the Origin of Life
Authors: Morrison Philip
Published: October 2006

The possibility that the intricate "organized elements" found in some carbonaceous chondrites are to be interpreted, not as microfossils of once-living cells, but as organic-chemical analogues of similarly intricate snow crystals is raised; tests and implications are discussed.
Surface Textures of Sand Grains: An Application of Electron Microscopy
Authors: Krinsley David , Takahashi Taro
Published: October 2006

Crushed quartz was subjected to wind, ball mill, and shaking-table action to simulate eolian and beach conditions. Electron microphotographs of these surfaces were then compared with those of grain surfaces which had been frosted naturally, and the correspondence between them was good. Thus, the transportation history of many sand deposits may be identified by this technique.
Punishment Inhibits an Instrumental Response in Hooded Rats
Authors: Storms Lowell H. , Boroczi George , Broen William E.
Published: October 2006

Punishment led to the cessation of a food-rewarded bar-pressing response in hooded rats deprived of food for 23 hours. The response remained inhibited for 2 weeks, and only one of four rats resumed responding when food deprivation was increased to 47 and 71 hours.
Programmed Death of T Cells in HIV-1 Infection
Authors: Meyaard Linde , Otto Sigrid A. , Jonker Richard R. , Mijnster M. Janneke , Keet René P. M. , Miedema Frank
Published: October 2006

In human immunodeficiency virus (HIV) infection, functional defects and deletion of antigen-reactive T cells are more frequent than can be explained by direct viral infection. On culturing, both CD4
+
and CD8
+
T cells from asymptomatic HIV-infected individuals died as a result of programmed cell death (apoptosis). Apoptosis was enhanced by activation with CD3 antibodies. Programmed cell death, associated with impaired T cell reactivity, may thus be responsible for the deletion of reactive T cells that contributes to HIV-induced immunodeficiency.
Comparative Genomic Hybridization for Molecular Cytogenetic Analysis of Solid Tumors
Authors: Kallioniemi Anne , Kallioniemi Olli-P. , Sudar Damir , Rutovitz Denis , Gray Joe W. , Waldman Fred , Pinkel Dan
Published: October 2006

Comparative genomic hybridization produces a map of DNA sequence copy number as a function of chromosomal location throughout the entire genome. Differentially labeled test DNA and normal reference DNA are hybridized simultaneously to normal chromosome spreads. The hybridization is detected with two different fluorochromes. Regions of gain or loss of DNA sequences, such as deletions, duplications, or amplifications, are seen as changes in the ratio of the intensities of the two fluorochromes along the target chromosomes. Analysis of tumor cell lines and primary bladder tumors identified 16 different regions of amplification, many in loci not previously known to be amplified.
Reductase Activity Encoded by the
HM1
Disease Resistance Gene in Maize
Authors: Johal Gurmukh S. , Briggs Steven P.
Published: October 2006

The
HM1
gene in maize controls both race-specific resistance to the fungus
Cochliobolus carbonum
race 1 and expression of the NADPH (reduced form of nicotinamide adenine dinucleotide phosphate)-dependent HC toxin reductase (HCTR), which inactivates HC toxin, a cyclic tetrapeptide produced by the fungus to permit infection. Several
HM1
alleles were generated and cloned by transposon-induced mutagenesis. The sequence of wild-type
HM1
shares homology with dihydroflavonol-4-reductase genes from maize, petunia, and snapdragon. Sequence homology is greatest in the βαβ-dinucleotide binding fold that is conserved among NADPH- and NADH (reduced form of nicotinamide adenine dinucleotide)-dependent reductases and dehydrogenases. This indicates that
HM1
encodes HCTR.
Estrogen-Sensitive Neurons and Sexual Behavior in Female Cats
Authors: Michael Richard P.
Published: October 2006

The stimulation of mating behavior by means of the stereotaxic introduction of small implants of solid C
14
-diethylstilbestrol di-n-butyrate to the hypothalamus of ovariectomized cats is described. Autoradiographic examination of the brains of mating animals reveals that certain neurons in the region of these implants show a selective affinity for labeled estrogen.
Bacteriophage Genes and Bacterial Functions
Authors: Luria S. E.
Published: October 2006

This brief survey of bacteriophage infection has provided support for an obvious but important generalization: that the study of virus infection at the cellular level is a branch of cellular genetics. The interactions between viral and cellular functions show that infection with a virus is not just a disrupting intrusion; it is an addition to the cellular endowment of genetic specificity. The outcome of this addition depends on the nature of the instructions carried by the viral genome, on the ability of the cellular machinery to carry out these instructions, and on the availability of control mechanisms to regulate the functions of the added element.
The Moon Illusion, II
Authors: Rock Irvin , Kaufman Lloyd
Published: October 2006

We have examined the two types of explanations of the moon illusion—the egocentric, in which the differences in direction of the horizon and the zenith moons are thought of in relation to different angles of regard of the observer, and the objective, in which the presence or absence of the terrain is considered crucial. The former type is exemplified chiefly by the eye-elevation hypothesis in the work of Boring and his colleagues; the latter, by the apparent-distance hypothesis based on the superior cues to distance provided by the terrain. Boring had rejected the apparent-distance hypothesis on the grounds that the horizon moon is reported as nearer, not farther away, by most observers. He then performed experiments which supported the eye-elevation hypothesis.
Staggerer, a New Mutation in the Mouse Affecting the Cerebellum
Authors: Sidman Richard L. , Lane Priscilla W. , Dickie Margaret M.
Published: October 2006

The "staggerer" mutant is recognized by its staggering gait, mild tremor, hypotonia, and small size. Symptoms develop during postnatal weeks 1 to 4 and remain stationary thereafter. The cerebellar cortex is grossly underdeveloped, with too few granule cells and unaligned Purkinje cells. Genetic linkage studies and neuropathological findings distinguish staggerer from other known mutants.
Autoimmune Response in Rabbits Injected with Rat and Rabbit Liver Ribosomes
Authors: Dodd Matthew C. , Bigley Nancy J. , Geyer Virginia B. , McCoy Francis W. , Wilson Henry E.
Published: October 2006

Autoimmune hemolytic anemia and leukopenia, circulating autoantibodies for erythrocytes, leukocytes, and ribosomes; pathological changes in liver, spleen, heart, brain, and kidneys were produced in rabbits injected with rat or rabbit liver ribosomes. The hematologic and pathologic changes were reproduced by injection of anti-ribosomal serum into normal rabbits. The autoantibody specificity was related primarily to nucleotides and nucleosides.
Iodine-129: Its Occurrence in Nature and Its Utility as a Tracer
Authors: Edwards R. R.
Published: October 2006

Natural production rates of the 16 million-year iodine-129 from spontaneous fission and from cosmic-ray reactions are estimated to contribute a steady-state concentration of more than 10
-14
gram of I
129
per gram of I
127
to the hydrosphere, the atmosphere, and the biosphere. These concentrations are expected to be detectable by neutron-activation analysis in natural materials that concentrate iodine. Substantial additional contributions have been made by fission-produced I
129
in fallout, serving as an intrinsic tracer for natural iodine kinetics. Iodine-129 activation analysis has advantages as a tracer technique.
Unit-Cell Dimensions of Natural and Synthetic Scapolites
Authors: Eugster Hans P. , Prostka Harold J. , Appleman Daniel E.
Published: October 2006

In natural scapolites the cell dimension
a
shows a regular increase from marialite to meionite composition, while
c
remains constant. Both
a
and
c
of synthetic meionite are larger than the corresponding dimensions of synthetic marialite. The cell volume of both natural and synthetic scapolites is a nearly linear function of composition. Variations in cell dimensions of scapolites may be caused by differences in structural state similar to those in plagioclase feldspars.
Chromatographic Validation of Two Morphologically Similar Hybrids of Different Origins
Authors: Alston R. E. , Turner B. L. , Lester R. N. , Horne David
Published: October 2006

The origin of natural hybrids of the plant
Baptisia
was determined by chromatographic analyses of leaf extracts of both hybrid and parent plants. This method demonstrated a pattern of inheritance in the hybrid of certain species-specific components of both parents.
Regulation of Arterial Tone by Activation of Calcium-Dependent Potassium Channels
Authors: Brayden Joseph E. , Nelson Mark T.
Published: October 2006

Blood pressure and tissue perfusion are controlled in part by the level of intrinsic (myogenic) vascular tone. However, many of the molecular determinants of this response are unknown. Evidence is now presented that the degree of myogenic tone is regulated in part by the activation of large-conductance calcium-activated potassium channels in arterial smooth muscle. Tetraethylammonium ion (TEA
+
) and charybdotoxin (CTX), at concentrations that block calcium-activated potassium channels in smooth muscle cells isolated from cerebral arteries, depolarized and constricted pressurized cerebral arteries with myogenic tone. Both TEA+ and CTX had little effect on arteries when intracellular calcium was reduced by lowering intravascular pressure or by blocking calcium channels. Elevation of intravascular pressure through membrane depolarization and an increase in intracellular calcium may activate calcium-activated potassium channels. Thus, these channels may serve as a negative feedback pathway to control the degree of membrane depolarization and vasoconstriction.
Association of a 59-kilodalton immunophilin with the glucocorticoid receptor complex
Authors: Tai Ping-Kaung Ku , Albers Mark W. , Chang Hong , Faber Lee E. , Schreiber Stuart L.
Published: October 2006

Immunophilins, a family of proteins that exhibit rotamase (peptidyl-prolyl
cis-trans
isomerase) activity in vitro, are expressed in many organisms and most tissues. Although some immunophilins can mediate the immunosuppressive actions of FK506, rapamycin, and cyclosporin A, the physiological role of the unligated proteins is not known. A 59-kilodalton member of the FK506- and rapamycin-binding class was found to associate in the absence of these drugs with two heat shock proteins (hsp90 and hsp70) and the glucocorticoid receptor (GR). Together, these proteins make up the inactive GR, thus biochemically linking two families of proteins proposed to be involved in protein folding and assembly as well as two potent immunosuppressive modalities.
Analysis of the
Escherichia coli
Genome: DNA Sequence of the Region from 84.5 to 86.5 Minutes
Authors: Daniels Donna L. , Plunkett Guy , Burland Valerie , Blattner Frederick R.
Published: October 2006

The DNA sequence of 91.4 kilobases of the
Escherichia coli
K-12 genome, spanning the region between
rrnC
at 84.5 minutes and
rrnA
at 86.5 minutes on the genetic map (85 to 87 percent on the physical map), is described. Analysis of this sequence identified 82 potential coding regions (open reading frames) covering 84 percent of the sequenced interval. The arrangement of these open reading frames, together with the consensus promoter sequences and terminator-like sequences found by computer searches, made it possible to assign them to proposed transcriptional units. More than half the open reading frames correlated with known genes or functions suggested by similarity to other sequences. Those remaining encode still unidentified proteins. The sequenced region also contains several RNA genes and two types of repeated sequence elements were found. Intergenic regions include three "gray holes," 0.6 to 0.8 kilobases, with no recognizable functions.
Experimental Study of the Developing Mammalian Egg: Removal of the Zona Pellucida
Authors: Mintz Beatrice
Published: October 2006

The zona pellucida may be removed from all stages of the mouse egg by digestion with pronase. Cumulus and corona cells are also dispersed by the enzyme. No change in membrane disgestibility occurs at fertilization. In tests thus far of two-cell eggs and later stages, development continues. Blastocysts exhibit "hatching" behavior despite absence of the zona. Functions of the zona include maintenance of the normal cleavage pattern and prevention of egg fusion.
Second Order Neurons in the Acoustic Nerve
Authors: Harrison J. M. , Warr W. Bruce , Irving R. E.
Published: October 2006

In silver-stained preparations of the rat auditory system large neurons were distributed over the whole length of the acoustic nerve. These neurons received many synaptic endings which arose from collaterals of the acoustic fibers. The axons of the neurons ascended toward the cochlear nuclei. Similar neurons were found in the mouse, but not in the bat or cat.
Tentoxin Sensitivity of Chloroplasts Determined by Codon 83 of β Subunit of Proton-ATPase
Authors: Avni Adi , Anderson James D. , Holland Neta , Rochaix Jean-David , Gromet-Elhanan Zippora , Edelman Marvin
Published: October 2006

Tentoxin is a naturally occurring phytotoxic peptide that causes seedling chlorosis and arrests growth in sensitive plants and algae. In vitro, it inhibits activity of the β subunit of the plastid proton-adenosine triphosphatase (ATPase) from sensitive species. Plastid
atp
B genes from six closely related, tentoxin-sensitive or -resistant
Nicotiana
species differ at codon 83, according to their response to the toxin: glutamate correlated with resistance and aspartate correlated with sensitivity. The genetic relevance of this site was confirmed in
Chlamydomonas reinhardtii
by chloroplast transformation. The alga, normally tentoxin-resistant, was rendered tentoxin-sensitive by mutagenesis of its plastid
atp
B gene at codon 83. Codon 83 may represent a critical site on the β subunit that does not compete with nucleotide binding or other catalytic activities.
Midbrain Reticular Influences upon Single Neurons in Lateral Geniculate Nucleus
Authors: Ogawa Tetsuro
Published: October 2006

The effect of electrical stimulation of the midbrain reticular formation upon patterns of discharge of single lateral geniculate neurons was studied. Data were processed by means of a 256-channel scaler analyzer. The rate of spontaneous discharge of geniculate neurons was raised by electrical stimulation of the reticular formation and their ability to respond to intermittent light was enhanced.
Tremoctopus violaceus
Uses
Physalia
Tentacles as Weapons
Authors: Jones Everet C.
Published: October 2006

Immature octopods (
Tremoctopus violaceus
) have been found with numerous fragments of tentacles of the coelenterate
Physalia
attached to the suckers of their dorsal arms. The probable method of acquisition, the evidence of adaptation for holding the tentacles, and the possibility that the octopod uses these coelenterate tentacles as offensive and defensive weapons are discussed.
Aluminum Silicate System: Experimental Determination of the Triple Point
Authors: Bell Peter M.
Published: October 2006

The kyanite-sillimanite-andalusite triple point exists in the pressure-temperature plane at 8 ± 0.5 kb and 300 ± 50°C. Reactions are accomplished experimentally with a Bridgman opposed-anvil press (with an external furnace), modified to provide shearing of the sample charges. All three equilibrium boundaries are proved by reversed reactions.
Electroencephalographic Changes after Prolonged Sensory and Perceptual Deprivation
Authors: Zubek John P. , Welch G.
Published: October 2006

Seven days' exposure to unpatterned light and white noise produced a significantly greater decrease in occipital lobe frequencies than did the same period of darkness and silence. This differential effect may be related to the greater behavioral impairments which seem to occur after prolonged exposure to diffuse light and noise.
Hydrogen-Water Vapor Mixtures: Control of Hydrothermal Atmospheres by Hydrogen Osmosis
Authors: Shaw Herbert R.
Published: October 2006

Experiments at 700°C and 800 bars total pressure demonstrate positive deviations from ideality for mixtures of hydrogen and H
2
O gases. The deviations are greater than predicted with Stockmayer's method. The composition of the mixture and the fugacity of hydrogen are controlled by diffusing hydrogen through metallic membranes. The results give the fugacities of both H
2
O and oxygen.
Statistically Defined Displays and Pattern Detection of Cerebral Palsied Children
Authors: Reed Charles F. , Pollack Alan
Published: October 2006

Visual displays consisting of arrays of dots are proposed as a possible method for quantifying the parameters of the hidden-figures tests. Detection of form in such displays is difficult for cerebral palsied children as a group. Oculomotor control may be one of the determining factors in successful performance of the perceptual task.
Infrared Spectra of Hydronium Ion in Micaceous Minerals
Authors: White Joe L. , Burns Allan F.
Published: October 2006

X-ray diffraction measurements of the
d
(001)
spacing and the infrared absorption spectra of hydrogen-saturated micas show that an ion of approximately the same size and properties as hydronium is present and gives a unique absorption band at about 3470 cm
-1
.
Low Dose Radiation of the Developing Brain
Authors: Hicks Samuel P. , D'Amato Constance J.
Published: October 2006

X-irradiation administered in single doses of 10 to 40 r has a widespread effect on the developing rat brain. It first diminishes the formation of cytoplasmic basophilic material in the nerve cells and inhibits their growth. Single doses of 20 to 40 r cause permanent alterations of individual nerve cells, and interfere with their organization into neuronal assemblies, such as layers of the cerebral cortex.
Isolation of a Viral Agent from Pseudocowpox Disease
Authors: Moscovici Carlo , Cohen Edward P. , Sanders James , DeLong Sara S.
Published: October 2006

A virus with characteristics similar to the pox group was isolated in tissue culture from bovine skin and oral lesions typical of pseudocowpox. The properties of this agent, certain of which differ from vaccinia virus, suggest that the isolate is the etiologic agent of the pseudocowpox syndrome.
Aberrant Thyroid Tissue in the Mouse
Authors: Hunt Ronald D.
Published: October 2006

Aberrant thyroid tissue was observed at the base of the heart in seven of 2634 mice of the BALB/c strain. Such tissue was not seen in any of 1033 mice of the Strong A strain. The normal thyroid gland of the BALB/c mouse was observed to be more loose than that of the Strong A mouse and isolated follicles were frequently observed in tissue sections at either pole of the gland which were not attached to the body of the thyroid.
Formation of a Gated Channel by a Ligand-Specific Transport Protein in the Bacterial Outer Membrane
Authors: Rutz Jeanette M. , Liu Jun , Lyons Jeri Ann , Goranson Joanne , Armstrong Sandra K. , McIntosh Mark A. , Feix Jimmy B. , Klebba Phillip E.
Published: October 2006

The ferric enterobactin receptor (FepA) is a high-affinity ligand-specific transport protein in the outer membrane of Gram-negative bacteria. Deletion of the cell-surface ligand-binding peptides of FepA generated mutant proteins that were incapable of high-affinity uptake but that instead formed nonspecific, passive channels in the outer membrane. Unlike native FepA, these pores acted independently of the accessory protein TonB, which suggests that FepA is a gated porin and that TonB acts as its gatekeeper by facilitating the entry of ligands into the FepA channel. The sequence homology among TonB-dependent proteins suggests that all ligand-specific outer membrane receptors may function by this gated-porin mechanism.
Interaction of the Immunosuppressant Deoxyspergualin with a Member of the Hsp70 Family of Heat Shock Proteins
Authors: Nadler Steven G. , Tepper Mark A. , Schacter Bernice , Mazzucco Charles E.
Published: October 2006

Deoxyspergualin (DSG) is a potent immunosuppressant whose mechanism of action remains unknown. To elucidate its mechanism of action, an intracellular DSG binding protein was identified. DSG has now been shown to bind specifically to Hsc70, the constitutive or cognate member of the heat shock protein 70 (Hsp70) protein family. The members of the Hsp70 family of heat shock proteins are important for many cellular processes, including immune responses, and this finding suggests that heat shock proteins may represent a class of immunosuppressant binding proteins, or immunophilins, distinct from the previously identified
cis-trans
proline isomerases. DSG may provide a tool for understanding the function of heat shock proteins in immunological processes.
Genetic Linkage Evidence for a Familial Alzheimer's Disease Locus on Chromosome 14
Authors: Schellenberg Gerard D. , Bird Thomas D. , Wijsman Ellen M. , Orr Harry T. , Anderson Leojean , Nemens Ellen , White June A. , Bonnycastle Lori , Weber James L. , Alonso M. Elisa , Potter Huntington , Heston Leonard L. , Martin George M.
Published: October 2006

Linkage analysis was used to search the genome for chromosomal regions harboring familial Alzheimer's disease genes. Markers on chromosome 14 gave highly significant positive lod scores in early-onset non-Volga German kindreds; a Z
max
of 9.15 (θ = 0.01) was obtained with the marker D14S43 at 14q24.3. One early-onset family yielded a lod score of 4.89 (θ = 0.0). When no assumptions were made about age-dependent penetrance, significant results were still obtained (Z
max
= 5.94, θ = 0.0), despite the loss of power to detect linkage under these conditions. Results for the Volga German families were either negative or nonsignificant for markers in this region. Thus, evidence indicates a familial Alzheimer's disease locus on chromosome 14.
Venom Collection from Honey Bees
Authors: Benton Allen W. , Morse Roger A. , Stewart Joseph D.
Published: October 2006

A device that provides an electric shock makes it possible to collect pure venom from several thousand honey bees (
Apis mellifera
). The collection apparatus fits underneath the brood chamber of a colony of bees and may be moved from hive to hive. Each colony is "milked" for 5 minutes. An average of 20 hives must be "milked" to obtain 1 gram of venom. Under optimum conditions this quantity of venom is produced by 10,000 worker bees.
Aragonite and Calcite as Constituents of Adult Oyster Shells
Authors: Stenzel H. B.
Published: October 2006

Adult oyster shells are composed mainly of calcite, but there are five small areas of aragonite: the resilium, the two pads at which the adductor muscle is inserted, and the two pads at which Quenstedt's muscles are inserted. Quenstedt's muscles are proposed as a name for the small modified, one-time pedal muscles of unknown function, discovered by Quenstedt.
Free Radicals and Reactive Molecules in Clathrate Cavities
Authors: Goldberg Paul
Published: October 2006

Reactive molecules and free radicals, when located in the cavities of the water clathrate lattice, can be prevented from recombining at temperatures almost up to the decomposition point of the lattice. The active species are produced by selective photochemical dissociation of the guest molecules in the clathrate compounds. Data taken from water clathrates of H
2
S, CH
3
SH, and C
2
H
5
SH suggest that S
2
, CH
3
S and C
2
H
5
S can be preserved in this way.
Contour Interaction and Visual Resolution: Contralateral Effects
Authors: Flom Merton C. , Heath Gordon G. , Takahashi Ellen
Published: October 2006

Detection of the gap in a four-position Landolt C presented to one eye is impaired by critically spaced surrounding bars seen only by the other eye. The intensity and spatial extent of this contralateral contour interaction match those obtained ipsilaterally. These results indicate that the neural site for this loss of visual information is supraretinal.
Ozone Formation in Air Exposed to Cobalt-60 Gamma Radiation
Authors: Kertesz Z. I. , Parsons Grace F.
Published: October 2006

The amount of ozone formed in air exposed to a 4000-curie cobalt-60 radiation source was determined. In closed glass containers exposed to about 1 Mrad of gamma radiation, ozone concentrations up to 18 parts per million (by volume) were recorded. In air flowing through a glass structure placed near the source, ozone contents up to 0.1 parts per million were observed. It is suggested that ozone formation might be a factor in the reported germicidal effects of ionizing radiations and that damage to plant tissues, ascribed to radiation, might have resulted from exposure to ozone. The possible health hazards from the ozone produced during irradiation should not be overlooked.
Long-Term Stability of Visually Evoked Potentials in Man
Authors: Dustman Robert E. , Beck Edward C.
Published: October 2006

Although the variability of averaged evoked potentials as recorded from cortex in man has been a constant source of concern among investigators, the degree of variability has not received systematic treatment. The authors have accordingly undertaken an exploratory study of reliable differences that may occur in the first 300 msec of the averaged evoked response over long periods of time. Computer analysis of visually evoked responses in seven subjects over several weeks indicated stability of the response of each individual, with reliable intra-individual correlations. Inter-individual differences, however, were large. The evoked responses of different individuals were found to be unique.
Feeding Response in
Aedes aegypti
: Stimulation by Adenosine Triphosphate
Authors: Galun Rachel , Avi-Dor Y. , Bar-Zeev M.
Published: October 2006

Taste receptors which evoke ingestion of blood in the mosquito,
Aedes aegypti
L., are stimulated by adenosine tetraphosphate, adenosine triphosphate, and adenosine monophosphate, in decreasing order. No other nucleotide is effective. Certain chelators can partially simulate the effect of nucleotides. The feeding response is elicited only at an osmotic pressure close to that of blood, and requires the presence of sodium ions.
Equatorial Undercurrent of the Indian Ocean
Authors: Knauss John A. , Taft Bruce A.
Published: October 2006

Measurements of currents at the equator in the Indian Ocean indicate the presence of an equatorial undercurrent. This current is similar in many respects to the undercurrent in the Pacific and Atlantic oceans. The undercurrent in the Indian Ocean is located in the thermocline and is of low magnitude, unsteady, and more strongly developed on the eastern side of the ocean.
Diabetes Mellitus in the Sand Rat Induced by Standard Laboratory Diets
Authors: Schmidt-Nielsen Knut , Haines Howard B. , Hackel Donald B.
Published: October 2006

During an attempt to establish a laboratory colony of the sand rat (
Psammomys obesus
) we found that this animal invariably became obese and developed severe diabetes mellitus when fed on commercial laboratory rat feed, but remained normal when fed on fresh vegetables only. The signs of diabetes included elevated blood glucose, excessive glucose and ketone bodies in the urine, and cataracts. The diabetic animals showed degeneration of the pancreatic insulin-producing tissue (beta-cells).
Conversion of Leucoanthocyanins into the Corresponding Anthocyanidins
Authors: Joslyn M. A. , Goldstein J. L.
Published: October 2006

Purified preparations of leucoanthocyanins from several sources were heated in butanol-hydrochloric acid solutions from 50° to 90°C and the rate of production of cyanidin was measured. From the temperature dependence of this rate, the calculated energy of activation was of the order of magnitude of 20,000 calories. The rate-limiting step in this reaction was similar for two preparations tested, and of lower energy for a third, presumably of lower degree of polymerization.
Cytoplasmic Interaction between Macrophages and Lymphocytic Cells in Antibody Synthesis
Authors: Schoenberg M. D. , Mumaw V. R. , Moore R. D. , Weisberger A. S.
Published: October 2006

A direct cytoplasmic connection between macrophages and potential antibody-producing cells has been demonstrated in lymph nodes and spleen. This was observed in the tissues from both immunized and nonimmunized rabbits.
Sonic Energy Effects in Bovine Serum Albumin Solutions
Authors: Hess Eugene L. , Chun Paul W. L. , Crowley R. L.
Published: October 2006

Bovine serum solutions exposed to high-frequency sound were examined by ultracentrifugal, electrophoretic, viscometric, conductivity, light scattering, and optical rotatory dispersion procedures. Parameters determined with treated material were the same as those determined with untreated albumin solutions except for slight differences in rotation, the dispersion constant, and in weight-average molecular weight.
Absence of Microsomal Triglyceride Transfer Protein in Individuals with Abetalipoproteinemia
Authors: Wetterau John R. , Aggerbeck Lawrence P. , Bouma Marie-Elisabeth , Eisenberg Claude , Munck Anne , Hermier Michel , Schmitz Jacques , Gay Gerard , Rader Daniel J. , Gregg Richard E.
Published: October 2006

Abetalipoproteinemia is a human genetic disease that is characterized by a defect in the assembly or secretion of plasma very low density lipoproteins and chylomicrons. The microsomal triglyceride transfer protein (MTP), which is located in the lumen of microsomes isolated from the liver and intestine, has been proposed to function in lipoprotein assembly. MTP activity and the 88-kilodalton component of MTP were present in intestinal biopsy samples from eight control individuals but were absent in four abetalipoproteinemic subjects. This finding suggests that a defect in MTP is the basis for abetalipoproteinemia and that MTP is indeed required for lipoprotein assembly.
Uranium Contents of Ancient Man-Made Glass
Authors: Fleischer R. L. , Price P. B.
Published: October 2006

The concentrations of uranium impurities in a variety of ancient man-made glasses have been determined by counting the sites of neutron-induced fissions. There appears to be a chronological trend from low to high and back to low uranium contents over the past three millennia. Crude estimates of ages by fission-track counting should be possible with considerable labor for the group of glasses which was found to have the highest concentration of uranium.
Scaling of Apparent Viscosity
Authors: Stevens S. S. , Guirao Miguelina
Published: October 2006

Observers made numerical judgments of the apparent viscosities of silicone liquids whose absolute viscosities ranged from 10.3 to 95,000 centipoises. Judgments were made by three procedures: shaking or turning a bottle containing the liquid, stirring the liquid with a rod with the eyes blindfolded, and stirring with the eyes open. For all these methods of judging, apparent viscosity was found to grow as the absolute viscosity raised to a fractional power. The exponents ranged from 0.42 to 0.46. The perception of viscosity follows the psychophysical power law that seems to govern prothetic perceptual continua.
Cutaneous Sensitivity after Prolonged Visual Deprivation
Authors: Zubek John P. , Flye J. , Aftanas M.
Published: October 2006

Subjects who were placed in darkness for a week but who were otherwise exposed to a normal and varied sensory environment showed an increase in tactual acuity and in sensitivity to heat and pain. This cutaneous supersensitivity was still present several days after the termination of visual deprivation.
Mucopolysaccharidosis in a Cat with Arylsulfatase B Deficiency: A Model of Maroteaux-Lamy Syndrome
Authors: Jezyk Peter F. , Haskins Mark E. , Patterson Donald F. , Mellman William J. , Greenstein Michael
Published: October 2006

A Siamese cat that presented clinical signs similar to those seen in humans with mucopolysaccharidoses was studied. The animal excreted increased amounts of polymeric glycosaminoglycans in the urine, consisting almost entirely of dermatan sulfate. Electron microscopy of circulating polymorphonuclear leukocytes revealed the presence of many membrane-bound lamellar inclusion bodies. Sulfate incorporation studies with cultured skin fibroblasts indicated defective glycosaminoglycan degradation. These cells showed a deficiency in arylsulfatase B activity. The disorder appears similar or identical to the Maroteaux-Lamy syndrome described in humans.
Root Pressure in Conifers
Authors: O'Leary James W. , Kramer Paul J.
Published: October 2006

Exudation of sap was never observed to occur from stumps of detopped seedlings of loblolly pine or white spruce, but measurable exudation occurred from apical root segments, 4 to 8 centimeters long, which were removed from the root systems and observed individually. Fully suberized root segments of loblolly pine exuded as much or more sap than unsuberized roots. Exudation also occurred from detached sugar maple root segments, but not from stumps attached to entire root systems.
Chemiluminescence Resulting from Electrochemically Generated Species
Authors: Hercules David M.
Published: October 2006

Chemiluminescence is reported from chemical species produced during electrolysis of aromatic hydrocarbons in deoxygenated nonaqueous solvents. Emission occurs in the solution near the cathode, and the emitting species is the excited singlet state of the hydrocarbon. Oxygen exerts a severe quenching effect on the chemiluminescence. Possible mechanisms are discussed.
Calcified Ectodermal Collagens of Shark Tooth Enamel and Teleost Scale
Authors: Moss Melvin L. , Jones Sheila J. , Piez Karl A.
Published: October 2006

Amino acid analysis of protein from the enamel of shark teeth and from teleost scales shows the presence of collagens which can be classified chemically as ectodermal. This finding, together with results from a histological examination of the development of these tissues, constitutes strong evidence that both proteins are derived from the ectoderm, like the enamel of higher vertebrates. Since both are calcified, calcification cannot be a specific property of collagens of mesodermal origin alone.
Infrared Absorption of Hydroxyl Groups in Kaolinite
Authors: Farmer Victor C.
Published: October 2006

Effects of sample orientation on the hydroxyl absorption of kaolinite can be interpreted in terms of the structure indicated by x-ray investigations, in which the surface hydroxyl groups of each layer are directed toward the oxygen atoms on the surface of the next layer.
Ingestion of Crude Oil: Sublethal Effects in Herring Gull Chicks
Authors: Miller David S. , Peakall David B. , Kinter William B.
Published: October 2006

A single small oral dose of Kuwait or South Louisiana crude oil caused cessation of growth, osmoregulatory impairment, and hypertrophy of hepatic, adrenal, and nasal gland tissue in herring gull chicks living in a simulated marine environment. These findings suggest that ingesting crude oil causes multiple sublethal effects that might impair a bird's ability to survive at sea.
Subclasses of Human γ
2
-Globulin Based on Differences in the Heavy Polypeptide Chains
Authors: Terry William D. , Fahey John L.
Published: October 2006

Three subclasses of human γ
2
-globulin (IgG) molecules were detected in normal human serum with antiserums prepared in monkeys. These subclasses, designated γ
2a
-, γ
2b
-, and γ
2c
-globulins, have antibody activity. The distinguishing antigenic characteristics of each subclass were associated with the heavy polypeptide chains and the F (fast) fragments resulting from treatment of γ
2
-globulins with papain.
Endogenous Circadian Rhythm in Cytoplasm of
Acetabularia
: Influence of the Nucleus
Authors: Schweiger E. , Wallraff H. G. , Schweiger H. G.
Published: October 2006

It was shown by three different methods that in the unicellular and uninuclear green alga
Acetabularia
the nucleus is capable of determining the phase of the circadian rhythm of the oxygen balance in the cytoplasm.
Osmiophilic Reagents: New Cytochemical Principle for Light and Electron Microscopy
Authors: Hanker Jacob S. , Seaman Arlene R. , Weiss Leon P. , Ueno Hiromi , Bergman Ronald A. , Seligman Arnold M.
Published: October 2006

Established histochemical procedures have been altered by utilizing reagents which contain a group capable of reacting selectively with OsO
4
. This permits the cytochemical demonstration of a particular enzyme or functional group of a macromolecule with the light and electron microscope. The osmiophilic groups used thus far are mercapto, thiocarbamyl, and diazothioether. The "osmium black" produced at the site of reaction is electron opaque, is insoluble in lipids, and is not altered when the issue is embedded in acrylic and epoxy resins. Its fine amorphous character enables it to be maintained precisely in the electron beam.
DNA Sequencing by Primer Walking with Strings of Contiguous Hexamers
Authors: Kieleczawa Jan , Dunn John J. , Studier F. William
Published: October 2006

When template DNA is saturated with a single-stranded DNA binding protein (SSB), strings of three or four contiguous hexanucleotides (hexamers) can cooperate through base-stacking interactions to prime DNA synthesis specifically from the 3′ end of the string. Under the same conditions, priming by individual hexamers is suppressed. Strings of three or four hexamers representing more than 200 of the 4096 possible hexamers primed easily readable sequence ladders at more than 75 different sites in single-stranded or denatured double-stranded templates 6.4 kilobases to 40 kilobase pairs long, with a success rate of 60 to 90 percent. A synthesis of 1 micromole of hexamer supplies enough material for thousands of primings, so multiple libraries of all 4096 hexamers could be distributed at a reasonable cost. Such libraries would allow rapid and economical sequencing. Automating this strategy could increase the speed and efficiency of large-scale DNA sequencing by at least an order of magnitude.
Transpiration and Stomatal Opening with Changes in Carbon Dioxide Content of the Air
Authors: Pallas J. E.
Published: October 2006

Increasing the carbon dioxide content of air reduces the transpiration rate of corn and sorghum plants and, to a lesser extent, of cotton, soybean, and tomato plants by causing the stomata to close. Closure of corn and sorghum stomata occurred when the concentrations of carbon dioxide were 2000 and 3000 parts per million, respectively. Cotton, soybean, and tomato stomata did not close completely at concentrations of carbon dioxide up to 4000 parts per million.
Genetic Control in Guinea Pigs of Immune Response to Conjugates of Haptens and Poly-L-Lysine
Authors: Levine Bernard B. , Benacerraf Baruj
Published: October 2006

Random-bred Hartley strain guinea pigs which do not respond immunologically to conjugates of hapten and poly-L-lysine mere mated with heterozygous guinea pigs which do. These responders were considered heterozygous for this trait since their mating resulted in at least one nonresponder offspring. Of 31 offspring from 10 breeding pairs (nonresponder × heterozygous responder) 14 were responders. There was no evidence that this trait is sex-linked. This finding confirms the view that, in guinea pigs, development of an immune response to the aforementioned conjugates is a genetically transmitted autosomal, unigenic Mendelian dominant trait.
Crystal Packing of Molecules
Authors: Williams Donald E.
Published: October 2006

The packing position of a molecule of known or assumed dimensions in a crystal can be found by minimizing the energy of the crystal with respect to molecular position by the method of steepest descent. Molecular flexibility can be introduced by allowing internal rotation about selected bonds. The method can be used to solve the diffraction phase problem in appropriate cases.
Terrestrial Ratio of Potassium to Rubidium and the Composition of Earth's Mantle
Authors: Gast Paul W.
Published: October 2006

The ratios of potassium to rubidium determined for a series of oceanic volcanic rocks suggest that the K/Rb ratio of the upper mantle exceeds 1500. The similarity between this inferred K/Rb ratio for the mantle and that found in some achondritic meteorites suggests a similar overall composition for these materials.
Contact-Induced Cytotoxicity by Lymphoid Cells Containing Foreign Isoantigens
Authors: Möller Erna
Published: October 2006

In tissue culture, immune lymph node cells containing foreign histocompatibility antigens of the H-2 type exert marked cytotoxic effects on tumor cells incompatible with the H-2 antigen. An equally pronounced effect is obtained when normal allogeneic and semi-isologous lymphoid cells of F
1
hybrids are caused to aggregate around the target tumor cells by treating the cultures with either heat-inactivated rabbit antiserum to mouse cells or phytohemagglutinin. Isologous lymph node cells have no effect. Thus, aggregation of lymphoid cells and target cells is a necessary but insufficient requirement for cytotoxicity in vitro; in addition, close contact must be established between histoincompatible cells.
Theoretical Morphology of the Coiled Shell
Authors: Raup David M. , Michelson Arnold
Published: October 2006

In studying the functional significance of the coiled shell, it is important to be able to analyze the types that do not occur in nature as well as those represented by actual species. Both digital and analog computers are useful in constructing accurate pictures of the types that do not occur.
Cystinuria: Effect of D-Penicillamine on Plasma and Urinary Cystine Concentrations
Authors: Crawhall J. C. , Thompson C. J.
Published: October 2006

Administration of penicillamine reduced the concentration of cystine in the plasma and urine of patients with cystinuria; renal clearance of cystine, lysine, and arginine remained unchanged. Cysteine-penicillamine disulfide and penicillamine disulfide were detected in the plasma.