bluuebunny/crossref_metadata_2025 huggingface dataset:
Recombinant Cholinergic Differentiation Factor (Leukemia Inhibitory Factor) Regulates Sympathetic Neuron Phenotype by Alterations in the Size and Amounts of Neuropeptide mRNAs
Authors: Nawa Hiroyuki , Nakanishi Shigetada , Patterson Paul H.
Published: October 2006

Abstract: The cholinergic differentiation factor (CDF) in heart cells is identical to leukemia inhibitory factor (LIF). Recombinant CDF/LIF was shown to alter dramatically neurotransmitter production as well as the levels of several neuropeptides in cultured rat sympathetic neurons. Here it is shown that these changes are likely to be caused by alterations in the mRNA for these proteins and peptides. Growth in 1 nM recombinant CDF/LIF induces mRNA for acetyl CoA: choline‐O‐acetyltransferase [EC 2.3.1.6; choline acetyltransferase (ChAT)], somatostatin (SOM), substance P, and vasoactive intestinal polypeptide while lowering mRNA levels of tyrosine hydroxylase (EC 1.14.16.2) and neuropeptide Y (NPY). In addition, the sizes of the mRNAs for ChAT, SOM, and NPY are larger after recombinant CDF/LIF treatment.
Composition changes in gingival crevicular fluid during orthodontic tooth movement: comparisons between tension and compression sides
Authors: Dudic Alexander , Kiliaridis Stavros , Mombelli Andrea , Giannopoulou Catherine
Published: October 2006

The aim of this study was to evaluate whether the application of tension or compression forces exerted on the periodontium during the early phase of orthodontic tooth movement is reflected by differences in the composition of the gingival crevicular fluid (GCF), at the level of interleukin‐1β (IL‐1β), substance P (SP), and prostaglandin E2 (PGE2). Eighteen children (mean age 10.8 yr) starting orthodontic treatment were included in the study. Molar elastic separators were inserted mesially to two first upper or lower molars. One of the antagonist molars served as the control. GCF was collected from the mesial and distal sites of each molar, before (−7 d, 0 d) and immediately after (1 min, 1 h, 1 d, and 7 d) the placement of separators. The levels of IL‐1β, SP, and PGE2 were determined by enzme‐linked immunosorbent assay. At the orthodontically moved teeth, the GCF levels of IL‐1β, SP, and PGE2 were significantly higher than at the control teeth in both tension and compression sides, and at almost all occasions after insertion of separators. The increase, relative to baseline values, was generally higher in tension sides. For the control teeth, the three mediators remained at baseline levels throughout the experiment. The results suggest that IL‐1β, SP, and PGE2 levels in the GCF reflect the biologic activity in the periodontium during orthodontic tooth movement.
Predictors of recall assignment decisions by general dental practitioners performing routine oral examinations
Authors: Mettes Theodorus G. , Van Der Sanden Wil J. M. , Mulder Jan , Wensing Michel , Grol Richard P. T. M. , Plasschaert Alphons J. M.
Published: October 2006

The aim of this study was to explore the decision‐making behavior of general dental practitioners (GDPs) in performing routine oral examinations (ROEs). Change over time was studied by comparing data from a cohort sample of participants in two surveys in 2000 and 2005. A written questionnaire was sent to 809 dentists (509 responses were obtained) and 475 (61%) were used for analysis. Of the respondents, 347 also participated in the survey in 2000. The mean number of diagnostic ROE items per ROE was 6.9 (standard deviation = 1.7). Groups of GDPs were distinguished based on their answer to the question ‘Do you apply for all patients a fixed recall interval between two successive ROEs?’ and four personal profiles. Of the GDPs, 38.5% (n = 183) assigned fixed recall intervals (Fxs) for all patients. Individual recall intervals (Ivs) were applied by 61.5% (n = 292) of GDPs, depending on specific selected patient characteristics and risk factors. Logistic regression showed that GDPs applying Fxs also used fixed periods between successive bitewing radiographs. Furthermore, GDPs applying Ivs conducted more frequent periodontal screening and, in the event of periodontal problems, were more inclined to prescribe radiographs. Over a 5 yr period, a shift towards Ivs assignment (from 49% in 2000 to 61.5% in 2005) was found. Differences in assigned recall intervals (Fxs/Ivs) by GDPs are determined by three clinical ROE predictors and two GDP profiles. A shift towards a more individual assessment was found between 2000 and 2005 in the way that Dutch GDPs are dealing with the assignment of recall interval frequency.
Spinothalamic Tract Neurons in the Substantia Gelatinosa
Authors: Willis W. D. , Leonard R. B. , Kenshalo D. R.
Published: October 2006

The substantia gelatinosa of the mammalian spinal cord is generally believed to be a closed system; that is, its neurons are thought to project only to the substantia gelatinosa of the same or the contralateral side. Experiments in monkeys, using injections of the marker enzyme horseradish peroxidase, show that at least some neurons of the substantia gelatinosa project to the thalamus and thus belong to the spinothalamic tract. Such neurons include two cell types intrinsic to the gelatinosa, the central cells and the limitrophe cells of Cajal.
Distemperoid Virus Interference in Canine Distemper
Authors: Green Robert G. , Stulberg Cyril S.
Published: October 2006

A distemper virus modified by ferret passage so as to become a harmless vaccine for foxes and dogs exhibits the interference or cell-blockade phenomenon with respect to a virulent distemper infection in foxes. Ten control foxes receiving virulent distemper virus died, while 30 foxes receiving distemperoid virus in addition lived.
Seaweed Dermatitis: Structure of Lyngbyatoxin A
Authors: Cardellina John H. , Marner Franz-Josef , Moore Richard E.
Published: October 2006

A highly inflammatory and vesicatory substance, lyngbyatoxin A, has been isolated from the lipid extract of a Hawaiian shallow-water variety of
Lyngbya majuscula
Gomont; its gross structure was determined from chemical and spectral data. Lyngbyatoxin A is closely related to teleocidin B, a poisonous substance associated with several strains of
Streptomyces
.
A Line, Not a Space, Represents Visual Distinctness of Borders Formed by Different Colors
Authors: Tansley Brian W. , Boynton Robert M.
Published: October 2006

When observers are asked to rate the visual distinctness of borders formed by the junction of two photic stimuli, normal trichromatic subjects behave in a manner similar to that of tritanopes in a color mixture experiment. All stimuli that look the same to the tritanope produce the same border distinctness with any other stimulus. Sets of such stimuli, whose members do not form borders with each other, map as single points along a curved line, where the Euclidean distance between pairs of points representing the two stimuli is nearly proportional to the rated distinctness of the border formed between them. In the absence of luminance differences, the perception of contour apparently depends on the stimulation of only two cone types.
Light-Induced Changes in the Structure of Pigmented Granules in
Aplysia
Neurons
Authors: Henkart Maryanna
Published: October 2006

Pigmented granules in
Aplysia
neurons prepared in the dark contain material that appears to be composed of 50-angstrom globules and a precipitate, probably a calcium salt. On illumination the globules rearrange into paracrystalline arrays and membrane-like lamellae. The morphologic transformation may be related to calcium release from the granules, and the released calcium may mediate the light-evoked hyperpolarization described by others.
Cognitive Deficit Caused by Regional Depletion of Dopamine in Prefrontal Cortex of Rhesus Monkey
Authors: Brozoski Thomas J. , Brown Roger M. , Rosvold H. E. , Goldman Patricia S.
Published: October 2006

Depletion of dopamine in a circumscribed area of association cortex in rhesus monkeys produces an impairment in spatial delayed alternation performance nearly as severe as that caused by surgical ablation of the same area. This behavioral deficit can be pharmacologically reversed with dopamine agonists such as L-dopa and apomorphine. These data provide direct evidence that dopamine plays an important role in a specific cortical function.
Hybridization Analysis of Histone Messenger RNA: Association with Polyribosomes During the Cell Cycle
Authors: Stein J. L. , Thrall C. L. , Park W. D. , Mans R. J. , Stein G. S.
Published: October 2006

Hybridization of cell cycle stage-specific polyribosomal RNA's to histone complementary DNA indicates that histone messenger RNA sequences are present on polyribosomes of Hela S
3
cells only during the period of DNA replication.
Taste Aversions to Sexual Attractants
Authors: Johnston Robert E. , Zahorik Donna M.
Published: October 2006

The vaginal secretion of female hamsters serves as a sexual excitant or attractant for the male even in the absence of previous sexual experience, but attraction to the secretion can be altered with surprising ease by pairing ingestion of the secretion with gastrointestinal illness.
Spectroscopic Detection of Molecular Hydrogen Frozen in Interstellar Ices
Authors: Sandford Scott A. , Allamandola Louis J. , Geballe Thomas R.
Published: October 2006

A weak infrared absorption feature near 4141 wavenumbers (2.415 micrometers) in the spectrum of WL5, an infrared source in the ρ Ophiuchus cloud complex, has been detected. It is attributed to molecular hydrogen created by irradiation and frozen in situ into water-rich ices. A second, broader absorption at 4125 wavenumbers centimeters (2.424 micrometers) is probably due to methanol in the ices. The column densities of frozen molecular hydrogen and methanol are inferred to be about 2.5 × 10
18
and 3.0 × 10
19
, respectively. There is about three times more frozen molecular hydrogen than frozen carbon monoxide along this line of sight.
Persistence of Foreign Innervation on Reinnervated Goldfish Extraocular Muscles
Authors: Scott Sheryl A.
Published: October 2006

Behavioral observations have suggested that the function of foreign synapses on goldfish extraocular muscles can be repressed after reinnervation by the original nerve without any ultrastructural alterations. The present experiments demonstrate that even after behavioral repression foreign synapses are physiologically functional and that the original and foreign nerves can simultaneously innervate goldfish extraocular muscles.
Folate Transport by the Choroid Plexus in Vitro
Authors: Spector Reynold , Lorenzo A. V.
Published: October 2006

Reduced folates are transported from blood into cerebrospinal fluid against a concentration gradient. In vitro, folates were transported into and released by isolated rabbit choroid plexuses. The choroid plexus uptake mechanism was specific for folates, energy dependent, and depressed by cold temperatures. In vivo, the choroid plexus may transport folates from blood to cerebrospinal fluid.
Binaural Beats at High Frequencies
Authors: McFadden Dennis , Pasanen Edward G.
Published: October 2006

Binaural beats have long been believed to be audible only at low frequencies, but an interaction reminiscent of a binaural beat can sometimes be heard when different two-tone complexes of high frequency are presented to the two ears. The primary requirement is that the frequency separation in the complex at one ear be slightly different from that in the other—that is, that there be a small interaural difference in the envelope periodicities. This finding is in accord with other recent demonstrations that the auditory system is not deaf to interaural time differences at high frequencies.
Structure, Function, and Evolutionary Relationships of Fc Domains of Human Immunoglobulins A, G, M, and E
Authors: Low Teresa L. K. , Liu Yu-Sheng Victor , Putnam Frank W.
Published: October 2006

Human immunoglobulins A, G, M, and E have strong homology in amino acid sequence (about 30 percent) distributed nonuniformly throughout the Fc region. Immunoglobulins M and A are least alike in the first Fc domain and most alike in the second. Individual domains of heavy chains have evolved with different mutation rates but with conservation of essential structural features. No relation of primary structure to complement binding ability is apparent.
Genetic Characteristics of the HeLa Cell
Authors: Hsu Susan H. , Schacter Bernice Z. , Delaney Nancy L. , Miller Thomas B. , McKusick Victor A. , Kennett R. H. , Bodmer J. G. , Young D. , Bodmer W. F.
Published: October 2006

The genotype of the patient Henrietta Lacks from whose cervical carcinoma the HeLa cell was derived was deduced from the phenotypes of her husband and children, and from studies of the HeLa cell. Hemizygous expression of glucose-6-phosphate dehydrogenase in HeLa, together with the deduced heterozygosity of Mrs. Lacks, is consistent with clonal origin of her neoplasm.
Evolution of Repeated DNA Sequences by Unequal Crossover
Authors: Smith George P.
Published: October 2006

It is often supposed that highly repetitious DNA's arise only as a result of unusual mechanisms or in response to selective pressure. My arguments and simulations suggest, by contrast, that a pattern of tandem repeats is the natural state of DNA whose sequence is not maintained by selection. The simulations show that periodicities can develop readily from nonrepetitious DNA as a result of the random accumulation of random mutations and random homology-dependent unequal crossovers. The lengths of these periodicities, and the patterns of subrepeats within them, would fluctuate in evolution, with the probability of a given pattern being dependent on the unknown exact nature of the crossover mechanism. Qualitatively, then, unequal crossover provides a reasonable and uncontrived explanation for the prevalence of highly repeated sequences in DNA and for the patterns of periodicity they evince.
Amphibious Behavior of
Alligator mississippiensis
: Roles of a Circadian Rhythm and Light
Authors: Lang Jeffrey W.
Published: October 2006

Juvenile American alligators in outdoor pens moved out of and into the water at sunrise and sunset, respectively. When the natural light cycle was extended with artificial illumination, these movements gradually shifted into phase with the altered light cycles; therefore, the amphibious behavior was modulated by a circadian rhythm cued by light. Movement between land and water was characterized by a decrease in body temperature, which suggests that it was not simply a proximate heat-seeking response. After the movements had been in phase with the altered light cycles for a time, they spontaneously shifted back into phase with the natural light cycle. A changing response to light is viewed as an adaptation to seasonal changes in heat availability.
Binocular Interaction in Strabismic Kittens Deprived of Vision
Authors: Maffei L. , Bisti S.
Published: October 2006

Artificial strabismus in kittens decreases the proportion of binocularly driven units in area 17 of the cortex. This change in the binocular interaction of cortical cells also takes place if the kittens are deprived of vision from the day in which the strabismus is surgically produced to the day of the electrophysiological recording. Thus, altered motility of the eyes per se is sufficient to affect binocular interaction in the neurons of area 17 of the cortex.
Theory of Photochemical Reactions
Authors: Salem L.
Published: October 2006

Although the great number of electronic states available to an excited molecule might seem to preclude a coherent picture of photochemical reaction mechanisms, it is possible to bring out some basic features common to a great many reactions. The electronic states of the primary diradical intermediates, surface crossings, topicity, and avoided surface crossings have been shown to be essential components of the electronic theory of photochemical reactions.

Diradicals have four important electronic states. Knowing these states, and making a simple electron count, it is possible to draw state correlation diagrams. Some diagrams show a typical surface crossing of the ground singlet state with the lowest (singlet, triplet) pair of excited states, with clear-cut consequences for quantum yields under various conditions. In other reactions the surfaces stay apart. The critical discriminating feature that determines the type of correlation diagram is the topicity. Photochemical reactions can be classified according to topicity, which is useful in interpreting their mechanisms. Avoided surface crossings can also be classified into different types. Figure 7, which illustrates the interplay of a covalent and an ionic surface responsible for photochemical electron transfer, is a typical multidimensional representation of a photochemical reaction.

The chemical behavior of the excited zwitterionic states of common intermediates, such as twisted ethylene or diallyl, reflects the quantum mechanical nature of photochemical processes. In these states, for perfectly symmetric systems, charge oscillates back and forth between two symmetry-equivalent sites. Slight geometric perturbations can create a sudden polarization of the excited molecule, with localization of almost a full charge at one end of the molecule. A photon is transformed into an electrical signal thanks to an appropriate molecular distortion. Nature may have used this simple process in the
N
-retinylidene visual chromophore to trigger an electrical response to vision.
Brain Wave Components of the Contingent Negative Variation in Humans
Authors: Rohrbaugh John W. , Syndulko Karl , Lindsley Donald B.
Published: October 2006

In a contingent negative variation paradigm with two stimuli paired at an interstimulus interval of 4 seconds, two distinct waveforms having functional and topographic differences are observed. An early wave is maximal over the frontal cortex and is elicited by the warning stimulus. A later wave, maximal over the motor cortex, precedes the imperative stimulus and is identified with preparation for motor response.
Reinvestigation of Oak Leaf Roller Sex Pheromone Components and the Hypothesis That They Vary with Diet
Authors: Miller J. R. , Baker T. C. , Cardé R. T. , Roelofs W. L.
Published: October 2006

The sex pheromone of the oak leaf roller,
Archips semiferanus
, was identified as a specific blend (67 : 33) of
trans
-11- and
cis
-11-tetradecenyl acetates. The pheromone blend of females from a semisynthetic diet and from three oak species did not vary significantly. Males from these diets responded in the laboratory and the field only to treatments approximating the 67 : 33 blend. These findings conflict with the hypothesis that the composition and perception of moth sex pheromones vary with slight changes in diet.
Growth Promotion by Homocysteic Acid
Authors: Clopath Peter , Smith Virginia C. , McCully Kilmer S.
Published: October 2006

Homocysteic acid, HO
3
SCH
2
CH
2
CHNH
2
CO
2
H, promotes growth of hypophysectomized rats, assayed by observation of increased thickness of epiphyseal cartilage of the tibia and by observation of tail growth. Doses of homocysteic acid as low as 1 microgram per day for 4 days in the tibia assay and 2.5 milligrams per kilogram per day for 5 weeks in the tail assay were effective in promoting growth. Serum somatomedin activity, determined by the porcine cartilage disk assay, was also increased by homocysteic acid. These findings relate an area of sulfur amino acid metabolism to the physiological action of growth hormone, accelerated growth in homocystinuria, initiation of arteriosclerosis, and control of cellular growth.
d-Amphetamine-Induced Inhibition of Central Dopaminergic Neurons: Mediation by a Striato-Nigral Feedback Pathway
Authors: Bunney Benjamin S. , Achajanian George K.
Published: October 2006

Lesions of the striato-nigral pathway (that is, crus cerebri or vicinity of the tail of the caudate nucleus) markedly attenuate depressant effects of intravenousd-amphetamine on central dopaminergic cell activity. These results, coupled with previous data showing that microiontophoretic application ofd-amphetamine directly onto dopaminergic cells does not produce significant slowing, provide direct support for the hypothesis that the depressant effect ofd-amphetamine on these cells is mediated through a striato-nigral neuronal feedback loop.
High-Resolution Scanning Electron Microscopy of Bacteriophages 3C and T4
Authors: Broers A. N. , Panessa B. J. , Gennaro J. F.
Published: October 2006

An account is presented of the design and operation of a new scanning electron microscope, and its first application to the study of biological samples. Bacteriophages were chosen because much of their ultrastructure is beyond the resolution of the conventional scanning electron microscope. The new instrument permits examination of bulk samples with a resolution that exceeds, by at least a factor of 2.5, the resolution obtained in the best secondary electron scanning electron microscopes using high brightness guns, and exceeds by an order of magnitude the resolution of standard scanning electron microscopes using tungsten filament guns. It also permits examination of biological samples in scanning transmission mode at resolutions similar to conventional transmission electron microscopes.
Human Rhodopsin
Authors: Wald George , Brown Paul K.
Published: October 2006

Human rhodopsin in aqueous solution has λ
max.
of 493 mμ and is lower in the spectrum than the rhodopsins of all other known vertebrates, with the exception of certain deep-sea fishes. Its molar extinction is 40,000 ± 800. Like other rhodopsins, it bleaches to a mixture of opsin and all-
trans
retinene and is resynthesized by incubating opsin with neo-
b
(11-
cis
) retinene. The regenerated rhodopsin has the same λ
max.
as the extracted pigment; this is due, therefore, not to an unusual retinene but to a characteristic human opsin. The regeneration in solution from opsin and neo-
b
retinene is a second-order reaction with a half-time, at 29.5°C, of about 2.5 minutes. This is much faster than the synthesis of rhodopsin in the living human eye, and faster than human rod dark-adaptation; the rate of both processes
in vivo
must be limited by reactions which precede the union of neo-
b
retinene with opsin, the final step in rhodopsin synthesis. In the rods, rhodopsin is virtually in the solid state—highly oriented in close relation with other highly oriented molecules. In this situation its spectrum is displaced toward the red (λ
max.
500 mμ) and is narrower than in solution. For light entering the rods axially, rhodopsin has also a considerably increased extinction, some 1.5 times higher than when randomly oriented. The spectrum of rhodopsin in rods agrees well in form and position with the spectral sensitivity of human rod vision, measured at the retinal surface.
Human Bloodstains: Individualization by Crossed Electroimmunodiffusion
Authors: Sweet George H. , Elvins James W.
Published: October 2006

Crossed electroimmunodiffusion was evaluated as a means for establishing the individuality ("fingerprinting") of human bloodstains. In ten separate examinations on stains from each of ten persons there was at least one peak with a unique range in height so that individualization was possible. The heights of certain peaks showed statistically significant female-male differences.
Analgesia Mediated by a Direct Spinal Action of Narcotics
Authors: Yaksh Tony L. , Rudy Thomas A.
Published: October 2006

Narcotic analgetics administered directly into the spinal subarachnoid space of the rat via a chronically inserted catheter produce a potent analgesia that can be antagonized by naloxone. The narcotics, acting only at the spinal level, changed cord function to block not only spinal reflexes but also the operant response to painful stimuli.
Effect of Deafferentation on a Conditioned Avoidance Response
Authors: Knapp H. D. , Taub E. , Berman A. J.
Published: October 2006

To determine whether peripheral afferent pathways could be bypassed in the performance of purposive movement, a group of monkeys was trained to avoid shock by flexing a forelimb in response to an auditory stimulus. The dorsal roots of the responding limb were then sectioned. Postoperatively it was found that the affected limb could be reconditioned.
Cholinesterase in a Receptor
Authors: Loewenstein Werner R. , Molins D.
Published: October 2006

Cholinesterase is found at the sites for mechanoelectric conversion of Pacinian corpuscles; its acetylcholine-splitting activity is of the same order of magnitude as that of the cholinesterase at neuromuscular junctions. The enzyme is not a typical acetylcholinesterase.
Radiation Dose Rate and Mutation Frequency
Authors: Russell W. L. , Russell Liane Brauch , Kelly Elizabeth M.
Published: October 2006

New data have clearly confirmed the earlier finding that specific locus mutation rates obtained with chronic gamma irradiation of spermatogonia are lower than those obtained with acute x-rays. Since this result is in contrast to classical findings for
Drosophila
spermatozoa, and apparently contradicts one of the basic tenets of radiation genetics, it was important to determine what factors were responsible for it.

Experiments undertaken for this purpose reveal the following: (i) the lower mutation frequency is due mainly to difference in dose rate of radiation, rather than quality; (ii) a dose-rate effect is not obtained in experiments with mouse spermatozoa, confirming classical findings for spermatozoa, and indicating that the explanation for intensity dependence in spermatogonia resides in some characteristic of gametogenic stage; and (iii) a dose-rate effect is found not only in spermatogonia but also in oocytes, where cell selection is improbable, indicating that the radiation intensity effect is on the mutation process itself.

A threshold response for all mutations in spermatogonia and oocytes is not a necessary consequence of the findings. Plausible hypotheses consistent with the present results can lead to other predictions.

From a practical point of view, the results indicate that the genetic hazards, at least under some radiation conditions, may not be as great as those estimated from the mutation rates obtained with acute irradiation. However, it should not be forgotten that even the lower mutation rates obtained with the present intensity levels are still appreciable.
Phenylpyruvic Acid as a Possible Precursor of
o
-Hydroxyphenylacetic Acid in Man
Authors: Tashian Richard E.
Published: October 2006

The oral administration of phenylpyruvic acid to human subjects results in increased urinary excretion of
o
-hydroxyphenylacetic acid. This demonstrates that phenylpyruvic acid may act as a precursor for
o
-hydroxy derivatives of phenylalanine and suggests that the formation of
o
-tyrosine is not necessary to account for the excretion of
o
-hydroxyphenylacetic acid in phenylketonuria.
Models of Carcinogenesis as an Escape from Mitotic Inhibitors
Authors: Bell George I.
Published: October 2006

Diffusible mitotic inhibitors are assumed to govern proliferation of normal cells. Cancer cells may escape regulation by failing to either recognize or secrete inhibitors. In the latter case, probabilities and expected times for reaching a critical clone size are given. Patterns of proliferation will depend on whether the inhibitor concentration is locally or systemically determined.
Antibacterial Activity of Acyclic Decapeptide Analogs of Gramicidin S
Authors: Erlanger Bernard F. , Goode Louise
Published: October 2006

Three acyclic decapeptide analogs of gramicidin S, although found to possess antibacterial activity, apparently have modes of action which differ from that of the naturally occurring cyclic antibiotic. In contrast to the immediate action of gramicidin S, one of the decapeptides produced complete bacteriostasis only after several cell divisions had occurred. Furthermore, mixtures of gramicidin S with either of two of the acyclic peptides were synergistic. Some implications of these findings are discussed.
Anaerobiosis in Marine Sandy Beaches
Authors: Gordon Malcolm S.
Published: October 2006

Organisms living at depths greater than 5 to 10 cm in marine beaches composed of fine sand are completely anaerobic whenever their particular section of beach is covered by water. Anaerobic conditions are continuous if the slope of the beach is slight enough so that capillary forces keep the sand saturated with water even at low tide.
Delayed Visual Feedback and Behavior
Authors: Smith William M. , McCrary John W. , Smith Karl U.
Published: October 2006

By means of video-tape recording the visual presentation of a person's behavior as he carries out some task, can be delayed in such a way that the individual sees what he is doing a short time after he has done it. The effects of this delay of visual feedback on a variety of simple visual-motor tasks are found to be both marked and deleterious, and in some respects similar to the effects of delayed auditory feedback on speech and motor tasks.
Control of Behavior by Presentation of an Imprinted Stimulus
Authors: Peterson Neil
Published: October 2006

When presentation of an imprinted stimulus is contingent upon an arbitrarily chosen response, the rate of emission of this response increases. This control of responding requires a moving imprinted stimulus and does not require a following response by the duck.
Hormology in Nutrition
Authors: Luckey T. D. , Stone P. C.
Published: October 2006

Discrepancies in the growth curves for the sodium requirement of the cricket indicate that hormology may play an important role in the response to essential nutrients as well as to toxic compounds. Differentiation between stimulation of growth by a nonnutritive action and support of growth by an essential nutrient is difficult.
Modulation of DNA Binding Specificity by Alternative Splicing of the Wilms Tumor
wt1
Gene Transcript
Authors: Bickmore W. A. , Oghene K. , Little M. H. , Seawright A. , van Heyningen V. , Hastie N. D.
Published: October 2006

The technique of whole-genome polymerase chain reaction was used to study the DNA binding properties of the product of the
wt1
gene. The zinc finger region of this gene is alternatively spliced such that the major transcript encodes a protein with three extra amino acids between the third and fourth fingers. The minor form of the protein binds specifically to DNA. It is now shown that the major form of wt1 messenger RNA encodes a protein that binds to DNA with a specificity that differs from that of the minor form. Therefore, alternative splicing within the DNA binding domain of a transcription factor can generate proteins with distinct DNA binding specificities and probably different physiological targets.
Personality and Scholarship
Authors: Heist Paul , McConnell T. R. , Matsler Frank , Williams Phoebe
Published: October 2006

Two groups of National Merit Scholarship students were selected on the basis of attendance at educational institutions ranked high or low in the production of future scholars and scientists. Four hypotheses pertaining to expected personality differences between matched groups from both sources were explored by means of the following instruments: the Omnibus Personality Inventory, the Strong Vocational Interest Blank, and the Allport-Vernon-Lindzey Study of Values. In general, the hypotheses were firmly supported, and it was concluded that students of high ability attending highly productive institutions have a pattern of traits, values, and attitudes which is more closely related to serious intellectual pursuits than have students of high ability attending less productive institutions.
Territorial Behavior in Uganda Kob
Authors: Buechner Helmut K.
Published: October 2006

Territorial behavior of the Uganda kob,
Adenota kob thomasi
(P. L. Sclater), is largely the defense of small, fixed territories within a central area of concentrated territorial activity. This area is surrounded by a zone of more widely spaced territories. Females enter the territorial ground throughout the year for the purpose of breeding.
Control of Osmotic Pressure of Culture Solutions with Polyethylene Glycol
Authors: Lagerwerff J. V. , Ogata Gen , Eagle Harold E.
Published: October 2006

Experiments with kidney beans indicate that Carbowax polyethylene glycol, molecular weight 20,000, upon purification, may be used as an agent to control the osmotic pressure of plant nutrient solutions without the hazard of interference with normal metabolic processes. With the sodium electrode and the thermocouple psychrometer, interaction between ions and Carbowax is shown to lead to a slight dissociation of the latter.
Nature of "Sex-ratio" Agent in
Drosophila
Authors: Poulson D. F. , Sakaguchi B.
Published: October 2006

Several lines of evidence implicate small spirochetes, presumably treponemata, as etiologic agents in the production of the maternally transmitted "sex ratio" condition (SR) in
Drosophila nebulosa
, in
D. willistoni
, and in strains of
D. melanogaster
into which the SR condition has been artificially transferred. The presence of treponemata in the hemolymph of adult females of these species is completely correlated with the production of unisexual progenies and like this condition is dependent on the genotype of the host and of the infectious agent.
Instrumental Conditioning of Jugular Self-Infusion in the Rhesus Monkey
Authors: Clark Robert , Schuster Charles R. , Brady Joseph V.
Published: October 2006

A technique is described for self-infusion of pharmacologic agents in solution through a permanently indwelling jugular catheter in the rhesus monkey. The results of an experiment utilizing this technique demonstrate that an instrumental lever response can be conditioned, extinguished, reconditioned, and brought under stimulus control and reward-schedule control with saline self-infusion as the reinforcing stimulus.
Photoperiodic Response of an Albino Mutant of Einkorn Wheat in Aseptic Culture
Authors: Sugino Mamoru
Published: October 2006

An albino mutant of einkorn wheat which lacks plastid pigments was cultured in a test tube on nutrient agar medium containing 8 percent sucrose, under long and short photoperiods. The plants showed typical photoperiodic responses to long and short days, suggesting the presence of a pigment system, other than plastid pigments, which is sensitive to dim radiation.
Genetical and Geographic Studies on Isoniazid Inactivation
Authors: Sunahara Shigeichi , Urano Motoyuki , Ogawa Masatoshi
Published: October 2006

Rapid and slow inactivators of isoniazid are homozygotes, and intermediate inactivators are heterozygotes. There is no dominance between the two alleles. The chasm between Eskimos and Caucasians in isoniazid metabolism is bridged by our investigation of the races in the Far East.
Responses of Retinal Ganglion Cells to Exponentially Increasing Light Stimuli
Authors: Enroth-Cugell Christina , Jones Richard W.
Published: October 2006

Action potentials of ganglion cells were recorded extracellularly from opened cat eyes. It was found that inhibition, as judged by discharge frequency, may depend upon rate of change of light intensity. Apparently the balance between excitatory and inhibitory inputs at the ganglion cell level depends upon rate of change of illumination. Visual purple bleaching or sensory adaptation taking place during the stimulation does not explain the results.
Specific Acceptance of Cardiac Allograft After Treatment with Antibodies to ICAM-1 and LFA-1
Authors: Isobe Mitsuaki , Yagita Hideo , Okumura Ko , Ihara Akira
Published: October 2006

An indefinite survival of cardiac allografts between fully incompatible mice strains was observed when monoclonal antibodies (MAbs) to intercellular adhesion molecule-1 (ICAM-1) and leukocyte function-associated antigen-1 (LFA-1) were simultaneously administered after the transplantation for 6 days. Mice with long-term surviving cardiac allografts accepted skin grafts from the donor-strain but rejected skin grafts from a third-party strain. Because MAbs to ICAM-1 or LFA-1 alone were insufficient for prolonged tolerance, the two MAbs probably acted synergistically to induce specific unresponsiveness. Thus, ICAM-1—LFA-1 adhesion participates in the induction of allograft rejection and MAbs may be useful as therapeutic agents.
Uptake of Catecholamines by a Particulate Fraction of the Adrenal Medulla
Authors: Kirshner Norman
Published: October 2006

Chromaffin granules isolated from beef adrenal medulla took up C
14
-labeled catecholamines from an isotonic medium at 37°C at a rate approximately 20 times the rate at 0°C. The uptake was stimulated three- to five-fold by Mg
++
and adenosine triphosphate. Reserpine (1 × 10
-5
M
) caused a 90 percent inhibition of uptake; ethylenediaminetetraacetic acid completely inhibited the stimulation by magnesium and adenosine triphosphate, and the inhibition could be reversed by addition of excess Mg
++
.
Clay Mineralogy
Authors: Grim Ralph E.
Published: October 2006

The structures of the clay minerals are reasonably well known, but greater detail and more precision are needed if the properties of clays and soils are to be fully understood. For example, the selective adsorptive and catalytic properties and the reaction with organic materials vary with the character of the clay mineral, but the structural factors that control such properties are not well understood. Research is urgently needed on the structure of pure clay minerals and on the reactions of pure clay minerals with organic and inorganic materials. Much past research on clay-mineral reactions has little fundamental value because the clay that was used was composed of a mixture of minerals which were not well characterized. It is not a simple matter to find pure samples of many of the clay minerals, and to a considerable extent progress depends on finding such pure minerals or preparing them in the laboratory.
Early Stages of Motor Neuron Differentiation Revealed by Expression of Homeobox Gene
Islet-1
Authors: Ericson Johan , Thor Stefan , Edlund Thomas , Jessell Thomas M. , Yamada Toshiya
Published: October 2006

Motor neurons in the embryonic chick spinal cord express a homeobox gene,
Islet-1
, soon after their final mitotic division and before the appearance of other differentiated motor neuron properties. The expression of Islet-1 by neural cells is regulated by inductive signals from the floor plate and notochord. These results establish Islet-1 as the earliest marker of developing motor neurons. The molecular nature of the Islet-1 protein suggests that it may be involved in the establishment of motor neuron fate.
Protein Oxidation and Aging
Authors: Stadtman Earl R.
Published: October 2006

A number of systems that generate oxygen free radicals catalyze the oxidative modification of proteins. Such modifications mark enzymes for degradation by cytosolic neutral alkaline proteases. Protein oxidation contributes to the pool of damaged enzymes, which increases in size during aging and in various pathological states. The age-related increase in amounts of oxidized protein may reflect the age-dependent accumulation of unrepaired DNA damage that, in a random manner, affects the concentrations or activities of numerous factors that govern the rates of protein oxidation and the degradation of oxidized protein.
Reversibility of the Reinforcement Relation
Authors: Premack David
Published: October 2006

Parameters were identified for the rat which both made drinking more probable than running and running more probable than drinking. In the same subjects, depending upon which parameters were used, running reinforced drinking and drinking reinforced running. This relationship suggests that a "reward" is simply any response that is independently more probable than another response.
Oceanic Detritus
Authors: Parsons T. R. , Strickland J. D. H.
Published: October 2006

The quantity and chemical composition of oceanic detritus in the northeastern Pacific Ocean has been measured at different depths from the surface to 3000 meters. The results indicate that oceanic detritus must be considered as a source of food for secondary producers.
Basal Skin Resistance during Sleep and "Dreaming"
Authors: Hawkins David R. , Puryear Herbert B. , Wallace Charles D. , Deal William B. , Thomas Edwin S.
Published: October 2006

Basal skin resistance was measured continuously in sleeping human subjects. Instead of a hypothesized fall in basal skin resistance during periods of "dreaming" or emergent stage 1 electroencephalographic activity, there was a rise which generally coincided with the "dreaming" period. This finding, along with other recent studies, indicates that this stage of sleep is not just a light stage of sleep but is unique neurophysiologically.
Persistent Fear Responses in Rhesus Monkeys to the Optical Stimulus of "Looming"
Authors: Schiff William , Caviness James A. , Gibson James J.
Published: October 2006

The approach of an object corresponds with a spatiotemporal optical stimulus consisting of a symmetrical expansion of a closed contour in the field of view. The visual equivalent of impending collision was isolated and compared with its sequential inversion. Infant and adult rhesus monkeys manifested persistent avoidance responses to "looming" but not to the inverse. This visual stimulus alone is a strong exciter of avoidance, and the response appears early in life.
Classical Conditioning in Newborn Rats
Authors: Caldwell D. F. , Werboff J.
Published: October 2006

Newborn albino rats were trained according to classical conditioning procedure with one of four intervals between conditioned and unconditioned stimuli. A vibrotactile stimulus (conditioned stimulus) paired with an electric shock (unconditioned stimulus) was presented to the forelimb 80 times. The results demonstrate that conditioning takes place in newborn rats. However, levels of performance as a function of time intervals between stimuli did not resemble the levels traditionally reported for older animals.
Induction of Mucosal and Systemic Immunity to a Recombinant Simian Immunodeficiency Viral Protein
Authors: Lehner T. , Bergmeier L. A. , Panagiotidi C. , Tao L. , Brookes R. , Klavinskis L. S. , Walker P. , Walker J. , Ward R. G. , Hussain L. , Gearing A. J. H. , Adams S. E.
Published: October 2006

Heterosexual transmission through the cervico-vaginal mucosa is the principal route of human immunodeficiency virus (HIV) infection in Africa and is increasing in the United States and Europe. Vaginal immunization with simian immunodeficiency virus (SIV) had not yet been studied in nonhuman primates. Immune responses in macaques were investigated by stimulation of the genital and gut-associated lymphoid tissue with a recombinant, particulate SIV antigen. Vaginal, followed by oral, administration of the vaccine elicited three types of immunity: (i) gag protein p27-specific, secretory immunoglobulin A (IgA) and immunoglobulin G (IgG) in the vaginal fluid, (ii) specific CD4
+
T cell proliferation and helper function in B cell p27-specific IgA synthesis in the genital lymph nodes, and (iii) specific serum IgA and IgG, with CD4+ T cell proliferative and helper functions in the circulating blood.
Narcotic Antagonists as Analgesics
Authors: Archer S. , Albertson N. F. , Harris L. S. , Pierson Anne K. , Bird J. G. , Keats Arthur S. , Telford Jane , Papadopoulos C. N.
Published: October 2006

2-Dimethylallyl-5,9-dimethyl-2′-hydroxybenzomorphan (Win 20,228) was found to be a weak antagonist of morphine and meperidine, whereas 2-allyl-5-ethyl-2′-hydroxy-9-methyl-6,7-benzomorphan (Win 19,362) and 2-allyl-2′-hydroxy-5,9-dimethyl-6,7-benzomorphan (Win 19,631) were about three times as potent as nalorphine. Preliminary clinical trials indicate that Win 19,362 is about twice as potent as morphine as an analgesic but, like nalorphine, is capable of producing severe psychic side effects. Win 20,228 is estimated to be about half as active as morphine as an analgesic, but no bizarre psychic effects were reported at any dose tested. Studies of addiction liability with Win 20,228 in monkeys suggest that this compound will not support morphine addiction.
Preliminary Experiments on a Microbial Fuel Cell
Authors: Davis J. B. , Yarbrough H. F.
Published: October 2006

Experiments were initiated to determine whether microbes using a hydrocarbon as food could generate electrical energy. Experiments with ethane were unsuccessful, but when microbes or glucose oxidase were added to a solution of glucose, electrical output was observed, confirming in part previous observations. As far as we know, no one had previously tested hydrocarbons in this manner, although the several effects of microbial activity on redox potential are well known. Failure of the microbes employed to dehydrogenate ethane in the absence of molecular oxygen is discussed in the light of recently published experimental evidence.
Mechanism of Tissue Reconstruction by Dissociated Cells, II: Time-Course of Events
Authors: Steinberg Malcolm S.
Published: October 2006

The details of the process by which cells sort out and reconstruct tissues within aggregates containing two kinds of tissue cells have been correctly predicted from considerations of the kinetic and adhesive properties of such cells. The requisite properties are discreteness, motility, and differential mutual adhesiveness among the types of cells present.
Circadian Rhythm in the in vitro Response of Mouse Adrenal to Adrenocorticotropic Hormone
Authors: Ungar Frank , Halberg Franz
Published: October 2006

Adrenal corticosterone production resulting from adrenocorticotropic hormone (ACTH) stimulation in vitro depends upon the time of gland removal. This rhythm in adrenal reactivity to ACTH is out of phase with the corticosterone rhythm in serum of the mice used as donors of adrenals. The responsiveness of the gland to exogenous ACTH is highest when serum corticosterone levels are lowest.
Inhibition of Myeloid Differentiation by the Helix-Loop-Helix Protein Id
Authors: Kreider Brent L. , Benezra Robert , Rovera Giovanni , Kadesch Tom
Published: October 2006

Id is a helix-loop-helix (HLH) protein that represses activity of several basic helix-loop-helix (bHLH) proteins involved in cell type—specific transcription and cell lineage commitment. The myeloid precursor cell line 32DCl3(G) expressed Id messenger RNA, which was transiently decreased when cells were induced to terminally differentiate with granulocyte—colony-stimulating factor. Concomitant with the decrease of Id messenger RNA was the appearance in nuclear extracts of DNA binding proteins that recognized a canonical E-box motif, a DNA binding site for some bHLH proteins. Constitutive expression of an Id complementary DNA in 32DCl3(G) cells blocked their ability to differentiate and to induce E-box-binding activity. These results suggest that Id and, hence, bHLH proteins function in the process of myeloid differentiation.
Molecular Cloning of the Interleukin-1β Converting Enzyme
Authors: Cerretti Douglas Pat , Kozlosky Carl J. , Mosley Bruce , Nelson Nicole , Van Ness Kirk , Greenstreet Teresa A. , March Carl J. , Kronheim Shirley R. , Druck Teresa , Cannizzaro Linda A. , Huebner Kay , Black Roy A.
Published: October 2006

Interleukin-1β (IL-1β) mediates a wide range of immune and inflammatory responses. The active cytokine is generated by proteolytic cleavage of an inactive precursor. A complementary DNA encoding a protease that carries out this cleavage has been cloned. Recombinant expression in COS-7 cells enabled the cells to process precursor IL-1β to the mature form. Sequence analysis indicated that the enzyme itself may undergo proteolytic processing. The gene encoding the protease was mapped to chromosomal band 11q23, a site frequently involved in rearrangement in human cancers.