bluuebunny/crossref_metadata_2025 huggingface dataset:
Replication of Human Endothelial Cells in Culture
Authors: Lewis L. James , Hoak John C. , Maca Richard D. , Fry Glenna L.
Published: October 2006

Investigative studies dealing with the properties and functions of endothelial cells have been hampered because there has been little or no success in the isolation, growth, and passage of individual cells in large numbers. We have developed a system whereby pure cultures of endothelial cells derived from umbilical veins can be subcultured for at least five serial passages. Many facets of endothelial function and interaction can be evaluated with the use of this new adaptive system of isolation and culture.
6-Hydroxydopamine: Evidence for Superoxide Radical as an Oxidative Intermediate
Authors: Heikkila Richard E. , Cohen Gerald
Published: October 2006

Superoxide dismutase inhibited the autoxidation of 6-hydroxydopamine as measured by the rate of formation of a quinone and the rate of oxygen consumption. These observations demonstrate the formation of the superoxide radical during the autoxidation process. This finding may be relevant to the mechanism of adrenergic nerve terminal degeneration caused by 6-hydroxydopamine.
Impaired Learning and Decreased Cortical Norepinephrine after Bilateral Locus Coeruleus Lesions
Authors: Anlezark G. M. , Crow T. J. , Greenway A. P.
Published: October 2006

Bilateral lesions of the nucleus locus coeruleus in rats deplete the cerebral cortex of norepinephrine and significantly diminish the rate of increase of running for food reward in a simple L-shaped runway. As assessed in this situation, learning was absent in those rats with the most complete ablations of the locus coeruleus, although these rats showed normal weight gain and normal motor and exploratory activity.
MHPG Excretion in Depressive Disorders: Relation to Clinical Subtypes and Desynchronized Sleep
Authors: Schildkraut Joseph J. , Keeler Barbara A. , Papousek Mechtild , Hartmann Ernest
Published: October 2006

The urinary excretion of 3-methoxy-4-hydroxyphenylglycol (MHPG) was significantly lower in patients with manic-depressive depressions than in patients with chronic characterological depressions. There was an inverse relationship between MHPG excretion and the amount of time spent in desynchronized sleep, particularly in the manic-depressive disorders. Excretion of MHPG was not related to the degree of retardation, agitation, or anxiety in these patients.
Entrainment of the Body Temperature Rhythm in Rats: Effect of Color and Intensity of Environmental Light
Authors: McGuire Robert A. , Rand William M. , Wurtman Richard J.
Published: October 2006

The daily rhythm in body temperature in rats was continuously monitored during exposure to low-intensity environmental illumination of various colors in the visible and near-ultraviolet spectrum. The ability of phase shifts in the lighting schedule to induce concomitant changes in the rhythm was used to determine the spectral sensitivity of the retinal photoreceptor systems mediating rhythm entrainment. Green light (λ = 530 ± 45 nanometers) was most potent, and red (λ = 660 ± 19 nanometers) and ultraviolet (λ = 360 ± 34 nanometers) were least potent in entraining the temperature rhythm.
Catecholamine and Dibutyryl Cyclic AMP Effects on Myosin Adenosine Triphosphatase in Cultured Rat Heart Cells
Authors: Harary Isaac , Hoover Frank , Farley Barbara
Published: October 2006

Catecholamines and dibutyryl adenosine 3′,5′-monophosphate (dibutyryl cyclic AMP) increase the activity of myosin adenosine triphosphatase in cultured rat heart cells. Dichloroisoproterenol, an inhibitor of the beta receptor of the catecholamines, inhibits the action of the catecholamines but not of cyclic AMP.
Tropical Cyclone Bebe Creates a New Land Formation on Funafuti Atoll
Authors: Maragos James E. , Baines Graham B. K. , Beveridge Peter J.
Published: October 2006

A huge rubble rampart 18 kilometers long was formed at Funafuti Atoll during tropical cyclone Bebe on 21 October 1972. The material forming the rampart was derived from deeper water offshore. The formation appears to be permanent and indicates that tropical storms may play a significant role in the formation of atoll islets.
Wilson's Disease: Identification of an Abnormal Copper-Binding Protein
Authors: Evans G. W. , Dubois R. S. , Hambidge K. M.
Published: October 2006

The metal-binding protein metallothionein was isolated from the livers of Wilson's disease patients and control subjects. The metals were removed from the native protein to produce the apoprotein, and copperthionein was prepared by equilibrium dialysis. Copperthionein from Wilson's disease patients had a copper-binding constant four times as great as that of the protein from control subjects. These results suggest that the alterations in copper homeostasis in Wilson's disease result from the synthesis of an abnormal metal-binding protein with an increased affinity for copper.
N
-Nitrosation by Nitrite Ion in Neutral and Basic Medium
Authors: Keeper Larry K. , Roller Peter P.
Published: October 2006

Formaldehyde catalyzed the conversion of various secondary amines to nitrosamines in the
p
H range 6.4 to 11.0. Chloral was also an effective catalyst. The reaction proceeds easily enough to have potential synthetic applications; the proposed mechanism could explain some reported anomalies regarding the synthesis of carcinogenic
N
-nitroso compounds in vivo and in vitro.
Recombinant Inbred Lines: Value in the Genetic Analysis of Biochemical Variants
Authors: Swank Richard T. , Bailey D. W.
Published: October 2006

Analysis of inducibility by androgens and electrophoretic mobility of kidney glucuronidase in progenitor and derived recombinant inbred mouse lines suggests that a single major regulatory gene at or near the glucuronidase structural gene on chromosome 5 determines the rate of enzyme accumulation.
Gelatin: A Poor Substrate for a Mammalian Collagenase
Authors: McCroskery Peter A. , Wood Sumner , Harris Edward D.
Published: October 2006

A rabbit tumor collagenase was purified more than 5000-fold. In this form it degrades native collagen in helical conformation at 37°C,
p
H 7.6, into two fragments, but it had little capacity to cleave gelatin, an indication of the importance of higher-order structure of substrate for this enzyme in pure form. It is likely that, in vivo, enzymes other than collagenase degrade gelatin polypeptides produced by primary collagenolysis.
Brain Tryptophan Hydroxylation: Dependence on Arterial Oxygen Tension
Authors: Davis James N. , Carlsson A. , MacMillan Vernon , Siesjö Bo K.
Published: October 2006

The accumulation of cerebral 5-hydroxytryptophan after decarboxylase inhibition was decreased in rats maintained at arterial O
2
tensions below 60 mm-Hg. In contrast, brain lactate was stable above 40 mm-Hg and brain adenosine triphosphate, adenosine diphosphate, and adenosine monophosphate were unchanged above 30 mm-Hg. There was a linear correlation of brain 5-hydroxytryptophan accumulation to cerebral venous O
2
tension. Cerebral tryptophan hydroxylase appears to have a poor affinity for oxygen and to be affected by slight hypoxia. The resultant decreases in monoamine neurotransmitter metabolism may explain the behavioral changes of mild oxygen deprivation.
Prevention of Murine Lupus Nephritis by Carrier-Dependent Induction of Immunologic Tolerance to Denatured DNA
Authors: Borel Yves , Lewis Robert M. , Stollar B. David
Published: October 2006

Four nucleosides were covalently bound to isogeneic mouse immunoglobulin G (IgG) and injected into New Zealand mice. Mice that received the tetranucleoside isogeneic IgG from birth to 5 months of age failed to make antibody to denatured DNA. In contrast, mice that were similarly treated with tetranucleoside bovine serum albumin or tetranucleoside free of carrier produced the same amount of antibody to denatured DNA as did untreated mice of this strain. Mice that were rendered tolerant to denatured DNA by tetranucleoside isogeneic IgG failed to develop the chronic membranous glomerulonephritis that characterizes the renal lesions in animals of this strain.
Retinal Projections in Blind Snakes
Authors: Halpern Mimi
Published: October 2006

Following unilateral enucleation of blind snakes, serial sections of the brains were stained by the Fink-Heimer procedure; the sections revealed terminal degeneration in the lateral geniculate nucleus of the thalamus bilaterally, nucleus posterodorsalis of the pretectum bilaterally, and superficial layers of the contralateral optic tectum. The stained degenerating fibers in the tectum were considerably less dense than in the thalamus.
Monocular Spatial Distortions Induced by Marked Accommodation
Authors: Blank Karen , Enoch Jay M.
Published: October 2006

Contraction of the ciliary muscle during marked accommodation causes the leading edge of the retina to advance as much as 0.5 centimeter. Near the posterior pole of the eye, the upward and downward extensional strains on the retina should be reasonably balanced. In the horizontal meridian an asymmetry is introduced because of the nasal location of the optic nerve head. Observers were asked to bisect the space between two parallel lines while fixating a movable line lying near the midpoint of the two lines. The test was conducted with the target far from and near the subject, in the horizontal and vertical meridians, and was repeated with accommodation paralyzed by a cycloplegic agent. Marked accommodation induced significant spatial distortions in the horizontal meridian. The effect is largely retinal.
Food Production and the Energy Crisis
Authors: Pimentel David , Hurd L. E. , Bellotti A. C. , Forster M. J. , Oka I. N. , Sholes O. D. , Whitman R. J.
Published: October 2006

The principal raw material of modern U.S. agriculture is fossil fuel, whereas the labor input is relatively small (about 9 hours per crop acre). As agriculture is dependent upon fossil energy, crop production costs will also soar when fuel costs increase two- to fivefold. A return of 2.8 kcal of corn per 1 kcal of fuel input may then be uneconomical.

Green revolution agriculture also uses high energy crop production technology, especially with respect to fertilizers and pesticides. While one may not doubt the sincerity of the U.S. effort to share its agricultural technology so that the rest of the world can live and eat as it does, one must be realistic about the resources available to accomplish this mission. In the United States we are currently using an equivalent of 80 gallons of gasoline to produce an acre of corn. With fuel shortages and high prices to come, we wonder if many developing nations will be able to afford the technology of U.S. agriculture.

Problems have already occurred with green revolution crops, particularly problems related to pests. More critical problems are expected when there is a world energy crisis. A careful assessment should be made of the benefits, costs, and risks of high energy-demand green revolution agriculture in order to be certain that this program will not aggravate the already serious world food situation.

To reduce energy inputs, green revolution and U.S. agriculture might employ such alternatives as rotations and green manures to reduce the high energy demand of chemical fertilizers and pesticides. U.S. agriculture might also reduce energy expenditures by substituting some manpower currently displaced by mechanization.

While no one knows for certain what changes will have to be made, we can be sure that when conventional energy resources become scarce and expensive, the impact on agriculture as an industry and a way of life will be significant. This analysis is but a preliminary investigation of a significant agricultural problem that deserves careful attention and greater study before the energy situation becomes more critical.
Electrophysiological Identification of a Visual Area in Shark Telencephalon
Authors: Cohen David H. , Duff Thomas A. , Ebbesson Sven O. E.
Published: October 2006

Optic nerve stimulation in the shark evokes short-latency telencephalic field potentials localized to the ipsilateral, posterior central nucleus. Such a well-defined visual area in elasmobranch telencephalon further challenges classical formulations of forebrain evolution. Moreover, its ipsilateral representation confirms recent evidence for a crossed thalamotelencephalic visual projection.
Excess Lead in "Rusty Rock" 66095 and Implications for an Early Lunar Differentiation
Authors: Nunes P. D. , Tatsumoto Mitsunobu
Published: October 2006

Apollo 16 breccia 66095 contains a remarkably high amount of lead (15 parts per million), 85 percent of which is not supported by uranium and thorium in the rock. An acid leach experiment coupled with separate analyses of the whole rock and mineral fractions for uranium, thorium, and lead indicate that the excess lead has a lunar source and was apparently introduced about 4.0 × 10
9
years ago. The data also suggest that a major lunar crustal differentiation occurred about 4.47 × 10
9
years ago.
Hepatitis A: Detection by Immune Electron Microscopy of a Viruslike Antigen Associated with Acute Illness
Authors: Feinstone Stephen M. , Kapikian Albert Z. , Purcell Robert H.
Published: October 2006

Spherical 27-nanometer particles were visualized in stools obtained from hepatitis A patients in the acute phase of the disease. The particle was serologically specific for this disease, and every hepatitis A patient tested demonstrated a serologic response to this antigen. The findings suggest that it is the etiologic agent of hepatitis A.
Diffusion of Weak Acids across Lipid Bilayer Membranes: Effects of Chemical Reactions in the Unstirred Layers
Authors: Gutknecht John , Tosteson D. C.
Published: October 2006

Chemical reactions in the aqueous unstirred layers of solution adjacent to a membrane can have dramatic effects on the diffusion of solutes across that membrane. This is demonstrated by the diffusion of labeled salicylate and salicylic acid across a phospholipid bilayer membrane. Two types of chemical reactions are considered. The first is an isotopic exchange reaction between the ionic and nonionic forms of a weak acid, HA + *A
-
⇄ H*A + A
-
. This reaction provides a way of estimating the true membrane permeability to a highly permeant weak acid and also a way of estimating the thickness of the unstirred layers. The second chemical reaction, the dissociation of a weak acid, HA ⇄ H
+
+ A
-
, can be used to show how the presence or absence of buffers in the unstirred layers controls the net transport of permeant weak acids across a membrane. In principle, the addition of appropriate "antacid" buffers to salicylates can increase their rate of absorption from the stomach.
Evolution and the Biosynthesis of Ascorbic Acid
Authors: Chatterjee I. B.
Published: October 2006

The ability to synthesize ascorbic acid is absent in the insects, invertebrates, and fishes. The biosynthetic capacity started in the kidney of amphibians, resided in the kidney of reptiles, became transferred to the liver of mammals, and finally disappeared from the guinea pig, the flying mammals, monkey, and man. A similar transition in the biosynthetic ability was observed in the branched evolution of the birds.
Glycosylphosphatidylinositol: A Candidate System for Interleukin-2 Signal Transduction
Authors: Eardley Diane D. , Koshland Marian Elliott
Published: October 2006

The mechanism of interleukin-2 (IL-2) signal transduction was analyzed by use of an inducible B lymphoma. Like normal antigen-activated B lymphocytes, the lymphoma cells respond to IL-2 by proliferating and differentiating into antibody-secreting cells; both responses are blocked by a second interleukin, IL-4. Analyses of the signaling pathway showed that IL-2 stimulated the rapid hydrolysis of an inositol-containing glycolipid to yield two possible second messengers, a myristylated diacylglycerol and an inositol phosphate-glycan. The myristylated diacylglycerol response exhibited the same IL-2 dose dependence as the growth and differentiative responses, and the generation of both hydrolysis products was inhibited by IL-4. These correlations implicate the glycosyl-phosphatidylinositol system in the intracellular relay of the IL-2 signal.
In vivo Inhibition of Growth of Two Hormone-Dependent Mammary Tumors by Dibutyryl Cyclic AMP
Authors: Cho-Chung Yoon Sang , Gullino Pietro M.
Published: October 2006

Growth of hormone-dependent rat mammary tumors was arrested in vivo by N
6
,O
2
′-dibutyryl cyclic adenosine 3′,5′-monophosphate. Estrogen concentration did not change, but acid ribonuclease activity and synthesis increased during treatment with the dibutyryl cyclic nucleotide, as was shown during tumor regression due to hormonal deprivation. Growth arrest, thus, appears to derive from enhanced tissue catabolism.
Magnetic Field of Jupiter and Its Interaction with the Solar Wind
Authors: Smith E. J. , Davis L. , Jones D. E. , Colburn D. S. , Coleman P. J. , Dyal P. , Sonett C. P.
Published: October 2006

Jupiter's magnetic field and its interaction with the magnetized solar wind were observed with the Pioneer 10 vector helium magnetometer. The magnetic dipole is directed opposite to that of the earth with a moment of 4.0 gauss
R
J
3
(
R
J
, Jupiter radius), and an inclination of 15° lying in a system III meridian of 230°. The dipole is offset about 0.1
R
J
north of the equatorial plane and about 0.2
R
J
toward longitude 170°. There is severe stretching of the planetary field parallel to the equator throughout the outer magnetosphere, accompanied by a systematic departure from meridian planes. The field configuration implies substantial plasma effects inside the magnetosphere, such as thermal pressure, centrifugal forces, and differential rotation. As at the earth, the outer boundary is thin, not diffuse, and there is a detached bow shock.
Calcium Ion Release in Mechanically Disrupted Heart Cells
Authors: Kerrick W. Glenn L. , Best Philip M.
Published: October 2006

In cardiac muscle fibers which have had their sarcolemma disrupted intracellular stores of calcium ions can be released by the same chemical stimuli which cause their release from the sarcoplasmic reticulum of skinned skeletal muscle fibers. These stimuli are increases in calcium or caffeine concentrations and substitution of chloride for propionate or sodium for potassium in solutions bathing the fibers.
Protodolomite Synthesis at 100°C and Atmospheric Pressure
Authors: Gaines Alan M.
Published: October 2006

Ordered protodolomite, CaMg(CO
3
)
2
, has been synthesized at 100°C by reaction of metastable precipitated carbonates with aqueous magnesium-bearing solutions. Initial reaction products have expanded crystallographic cells, attributed to the presence of structural water. Longer reaction time produces a protodolomite approaching ideal composition and exhibiting order reflections in x-ray powder patterns.
Paradoxical Increase in Rate of Catabolism of Low-Density Lipoproteins after Hepatectomy
Authors: Sniderman Allan D. , Carew Thomas E. , Chandler James G. , Steinberg Daniel
Published: October 2006

It has been suggested that the liver may be a major site for irreversible degradation of low-density lipoprotein (LDL). The disappearance of autologous
125
I-labeled LDL from plasma was compared in intact and in hepatectomized swine. Contrary to expectations, the rate of irreversible removal of LDL from plasma was increased rather then decreased by hepatectomy. These studies suggest that the liver is not a major site for LDL removal. We propose further that the liver (or some function requiring an intact liver) may affect the metabolism of LDL in a manner that prolongs its lifetime in the plasma compartment.
Adenosine 3′,5′-Monophosphate: Inhibition of Complement-Mediated Cell Lysis
Authors: Kaliner Michael , Austen K. Frank
Published: October 2006

An increase in adenosine 3′,5′-monophosphate (cyclic AMP) in rat mast cells, achieved by stimulating the cells with prostaglandin E
1
, by preventing cyclic AMP breakdown with aminophylline, or by adding exogenous dibutyryl cyclic AMP, prevented complement-mediated cytolysis as assessed by both histamine release and vital dye exclusion. Dibutyryl cyclic AMP also suppressed water-induced osmotic lysis.
The Casparian Strip as a Barrier to the Movement of Lanthanum in Corn Roots
Authors: Nagahashi G. , Thomson W. W. , Leonard R. T.
Published: October 2006

The effectiveness of the Casparian strip as a barrier to apoplastic movement of solutes from cortex to stele of corn roots was investigated by using lanthanum in combination with electron microscopy. Lanthanum deposits were found only in cell walls and on the outside of the plasma membrane of epidermal, cortical, and endodermal cells up to the Casparian strip. Lanthanum was completely absent from the stele, indicating that the Casparian strip provides an effective barrier to apoplastic movement of solutes. Inhibitory effects of trivalent lanthanum ions on the absorption of potassium ions are discussed in relation to the nature of the lanthanum ion binding site on membranes.
Mammalian Pheromone: Identification of Active Component in the Subauricular Scent of the Male Pronghorn
Authors: Mller-Schwarze Dietland , Mller-Schwarze Christine , Singer Alan G. , Silverstein Robert M.
Published: October 2006

Male pronghorn (
Antilocapra americana
) mark vegetation by rubbing with their subauricular glands. Males respond to scent marks by sniffing, licking, thrashing, and marking. Hand-raised males were confronted with artificial scent marks consisting of whole extract of the subauricular gland or synthesized compounds corresponding to those identified from the extract. Of these, isovaleric acid released the strongest responses.
Low-Loss Niobium-Tin Compound for Superconducting Alternating-Current Power Transmission Applications
Authors: Suenaga M. , Garber M.
Published: October 2006

A Nb
3
Sn superconductor has been fabricated in rods and tapes by the interaction of the tin contained in a copper-tin alloy with niobium which had been in contact with the alloy material. This conductor has lower alternating-current (60 hertz) losses than any presently available commercial products.
Suppressing
Drosophila
Circadian Rhythm with Dim Light
Authors: Winfree Arthur T.
Published: October 2006

Drosophila
larvae were reared and allowed to pupate in continuous bright white light. The pupae were then transferred to a much dimmer blue light. In continuous blue light of intensity below 0.001 erg per square centimeter per second, adult flies emerged in pulses 24.7 hours apart, each pulse occupying about 6 hours. But in continuous light of intensity exceeding 0.1 erg per square centimeter per second, they emerged at a steady rate. This intensity range from effective darkness to effective light is roughly from starlight to moonlight. Inside this range, the emergence peaks broaden for about a week with little change of period.
The Economics of Resource Recovery from Municipal Solid Waste
Authors: Abert James G. , Alter Harvey , Bernheisel J. Frank
Published: October 2006

A prototypical operating statement similar to that used by business firms has been shown to be a useful decision-making tool for a community choosing a solid waste management system. When applied to resource recovery, it highlights the economics of recovery and the values of the input parameters necessary to achieve economic viability, whether in the case of public or private ownership.

In most communities, refuse processing to recover material resources must be based on more than one source of revenue. In addition to the revenues from the sale of by-products, there must be revenues from processing the incoming refuse and from a user, or dump, fee. In the first case discussed, that of materials recovery by a front end system, resource recovery is shown to be economically feasible for those communities in which the present cost of disposal is relatively high. The indifferent community was one having a current cost of $7.72 per ton; more accurately, this would be the cost for the near-term future. It is not necessary that current costs be used, since many communities are merely "dumping" their refuse. The indifference decision should be based on the cost of an environmentally sound alternative.

Energy recovery from municipal solid waste can increase the number of communities in which resource recovery will be an economic adjunct to a solid waste management system. The analysis presented here was based on the assumption that the value of the fuel recovered exactly offset the additional capital and operating costs of the utility which burns it. There could be costs above and beyond this; similarly, there could be a saving by taking into account the economic value of the organic fraction as fuel. However, it is believed that the assumption under which the materials-plus-energy case was analyzed seems to be realistic at this time.
Student-Faculty Evaluation
Authors: Zelby Leon W.
Published: October 2006

Desirable attributes of SFE can be vitiated by its premature utilization in a formal and quantitative sense. This is because it is possible to teach for a specific student evaluation, given a particular questionnaire. Consequently, because of the importance of SFE, the questionnaire must be designed to meet the expectations of the students, as well as the aspirations of the respective institutions. Indiscriminate use of SFE will increase the gap between first-rate and second-rate institutions—first-rate institutions will continue to attract more demanding students, a fact that will be reflected in SFE's, whereas second-rate institutions, in an effort to maintain levels of enrollment, may tend to formulate SFE's that emphasize popularity and mediocrity of education. Careful construction of the format of SFE, on the other hand, could do much toward increasing the quality of teaching, as well as the motivation of students and teachers, in many institutions.
Requirement for Positive Selection of γδ Receptor-Bearing T Cells
Authors: Wells Faith B. , Gahm Sara-Jo , Hedrick Stephen M. , Bluestone Jeffrey A. , Dent Alexander , Matis Louis A.
Published: October 2006

The αβ and γδ T cell receptors for antigen (TCR) delineate distinct T cell populations. TCRαβ-bearing thymocytes must be positively selected by binding of the TCR to major histocompatibility complex (MHC) molecules on thymic epithelium. To examine the requirement for positive selection of TCR γδ T cells, mice bearing a class I MHC-specific γδ transgene (Tg) were crossed to mice with disrupted β
2
microglobulin (β
2
M) genes. The Tg
+
β
2
M
-
(class I MHC
-
) offspring had Tg
+
thymocytes that did not proliferate to antigen or Tg-specific monoclonal antibody and few peripheral Tg
+
cells. This is evidence for positive selection within the γδ T cell subset.
A Retroviral Oncogene,
akt
, Encoding a Serine-Threonine Kinase Containing an SH2-Like Region
Authors: Bellacosa Alfonso , Testa Joseph R. , Staal Stephen P. , Tsichlis Philip N.
Published: October 2006

The v-
akt
oncogene codes for a 105-kilodalton fusion phosphoprotein containing Gag sequences at its amino terminus. Sequence analysis of v-
akt
and biochemical characterization of its product revealed that it codes for a protein kinase C-related serine-threonine kinase whose cellular homolog is expressed in most tissues, with the highest amount found in thymus. Although Akt is a serine-threonine kinase, part of its regulatory region is similar to the Src homology-2 domain, a structural motif characteristic of cytoplasmic tyrosine kinases that functions in protein-protein interactions. This suggests that Akt may form a functional link between tyrosine and serine-threonine phosphorylation pathways.
Heavy Metal Concentrations in Museum Fish Specimens: Effects of Preservatives and Time
Authors: Gibbs Robert H. , Jarosewich E. , Windom Herbert L.
Published: October 2006

Specimens of myctophid fish preserved for 1 month in formalin, ethyl alcohol, and isopropyl alcohol had higher concentrations of cadmium, copper, zinc, and sometimes lead, and lower concentrations of mercury and sometimes lead, than did unpreserved frozen specimens. Properties of the preservatives and species differences in fish tissues both influence these metal concentrations. Maximum concentrations of some metals in preserved specimens appear to be attained within a month, while concentrations of others may continue to increase for years. Metal tags or other materials in the preservative may cause higher maximum concentrations than the preservatives alone. Comparisons of concentrations of metals between museum specimens and unpreserved (frozen) specimens must be considered unreliable until the changes resulting from preservation are understood.
Coyote Predation Control by Aversive Conditioning
Authors: Gustavson Carl R. , Garcia John , Hankins Walter G. , Rusiniak Kenneth W.
Published: October 2006

Conditioned aversions were induced in coyotes by producing lithium chloride illness in them following a meal, and the effects upon eating and attack behavior were observed. One trial with a given meat and lithium is sufficient to establish a strong aversion which inhibits eating the flesh of that prey. One or two trials with a given flesh (lamb or rabbit) specifically suppresses the attack upon the averted prey but leaves the coyote free to attack the alternative prey. A method of saving both prey and predator is discussed.
Colonization of Exploded Volcanic Islands by Birds: The Supertramp Strategy
Authors: Diamond Jared M.
Published: October 2006

After volcanic explosions or tidal waves had defaunated several islands near New Guinea, bird species number rapidly returned to equilibrium on coral islets and rapidly returned to quasi-steady-state values limited by regrowth of vegetation in lowland forest of larger islands. However, reequilibration in montane forest has been limited by slow dispersal of the birds. Colonists have been drawn disproportionately from r-selected "supertramp" species, which maintain much higher population densities than do K-selected faunas, perhaps due to selection for resource overexploitation by the latter.
Continental Pleistocene Climatic Variations from Speleothem Age and Isotopic Data
Authors: Thompson Peter , Schwarcz Henry P. , Ford Derek C.
Published: October 2006

Speleothems from continental North American caves have been dated by means of the
230
Th/
234
U method. Oxygen isotopic variations in the dated samples and phases of speleothem deposition can be interpreted in terms of climatic change. A glacial chronology constructed from the age and isotopic data lends support to the astronomical theory of climatic change.
A Dominant Negative form of Transcription Activator mTFE3 Created by Differential Splicing
Authors: Roman Christopher , Cohn Lauren , Calame Kathryn
Published: October 2006

Transcription factor E3 (mTFE3) is a murine transcription activator that binds to the intronic enhancer of the immunoglobulin heavy chain gene. A naturally occurring splice product of mTFE3 messenger RNA (mRNA) lacked 105 nucleotides that encode an activation domain; both absolute and relative amounts of long and truncated mRNAs varied in different tissues. Cells were cotransfected with complementary DNAs that encoded the two mRNA forms in amounts that corresponded to the amounts of each mRNA found in different cells. Small changes in substoichiometric amounts of the truncated form of mRNA effected trans-dominant negative modulation of mTFE3 activity. These findings identify a function for differential splicing in the regulation of transcription factor activity.
Massive Cortical Reorganization After Sensory Deafferentation in Adult Macaques
Authors: Pons Tim P. , Garraghty Preston E. , Ommaya Alexander K. , Kaas Jon H. , Taub Edward , Mishkin Mortimer
Published: October 2006

After limited sensory deafferentations in adult primates, somatosensory cortical maps reorganize over a distance of 1 to 2 millimeters mediolaterally, that is, in the dimension along which different body parts are represented. This amount of reorganization was considered to be an upper limit imposed by the size of the projection zones of individual thalamocortical axons, which typically also extend a mediolateral distance of 1 to 2 millimeters. However, after extensive long-term deafferentations in adult primates, changes in cortical maps were found to be an order of magnitude greater than those previously described. These results show the need for a reevaluation of both the upper limit of cortical reorganization in adult primates and the mechanisms responsible for it.
Mineral Resources, Economic Growth, and World Population
Authors: Brooks David B. , Andrews P. W.
Published: October 2006

World population and world income can grow at any likely rate for the next 50 to 75 years, probably for longer, and mineral supplies will continue to keep pace with demand. Not, however, without environmental costs, without affecting Third World development, and, perhaps most important, without ignoring critical questions of power. In what might be termed the revisionist form of the limits to growth thesis, Aurelio Peccei and Alexander King, cofounders of the Club of Rome, seem to be saying that the forecasts of doom themselves are unimportant but they symbolize critical problems of the nature and uses of power in the modern world:

. . . the Club of Rome is questioning the quality of growth and its distribution around the world. . . . We know that the present structure of the world is obsolete. . . . Both private and state capitalism are stale . . . we have to develop something else.

Surely, continually increasing rates of mineral production are symptoms of this obsolete power structure, a result of the fact that, ultimately, population growth and monetary income growth lead to demands for natural resources that necessitate their being found and produced regardless of the implications. Since such higher rates of production are geologically and economically sustainable, we should choose among alternative paths of growth, and hence among alternative rates of mineral resource development, according to what we like or dislike about these implications. The key information will not be found in tables comparing reserves and consumption but in preferences and ethics.
Failure of Beta-Adrenergic Receptor Blockade to Prevent Arrhythmias Induced by Sympathetic Nerve Stimulation
Authors: Gillis Richard A. , Pearle David L. , Hoekman Theodore
Published: October 2006

Cardiac arrhythmias produced by electrical stimulation of the ventrolateral cardiac sympathetic nerve in dogs were not blocked by the combined administration of propranolol and practolol in amounts that completely blocked cardiac beta-adrenergic receptors. Blockade of cardiac alpha-adrenergic receptors, as well as cardiac cholinergic receptors, also had no influence on the arrhythmias. These results suggest that the adrenergic neuroeffector junction is fundamentally different from any hitherto described, differing perhaps in the neurotransmitter involved or in the nature of the receptor.
Testosterone Induces "Splitting" of Circadian Locomotor Activity Rhythms in Birds
Authors: Gwinner F.
Published: October 2006

Under the influence of testosterone, the free-running circadian rhythm of locomotor activity of the starling,
Sturnus vulgaris
, tends to "split" into two components which temporarily run with different circadian frequencies: "splitting" occurred in intact birds whose testes grew, and in castrated birds that were injected with testosterone. Since "splitting" most probably reflects the temporal separation of two (or two groups of) circadian oscillators, these results suggest that testosterone affects the mutual coupling of circadian oscillators controlling locomotor activity.
Ocular Hazard from Picosecond Pulses of Nd: YAG Laser Radiation
Authors: Ham William T. , Mueller Harold A. , Goldman Arnold I. , Newnam Brian E. , Holland L. M. , Kuwabara T.
Published: October 2006

Seven rhesus monkeys (14 eyes) were exposed to 1064-nanometer radiation in single pulses of 25 to 35 picoseconds from a mode-locked Nd: YAG laser. Threshold injury resulted from single pulses with a mean energy of 13 ± 3 microjoules. Electron microscopy of the retina revealed that damage was highly localized in the photoreceptor and pigmented epithelial cells at the outer retina. Membrane disruption, distorted outer segments, and abnormal melanin granules resembling fetal premelanosomes were observed.
Amphetamine Effects in Man: Paradoxical Drowsiness and Lowered Electrical Brain Activity (CNV)
Authors: Tecce Joseph J. , Cole Jonathan O.
Published: October 2006

Thirteen of 20 normal adults given 10 milligrams of dextroamphetamine exhibited paradoxical drowsiness accompanied by lowered electrical brain activity (contingent negative variation, or CNV) in the first hour post-drug. During this period, seven subjects showed behavioral alertness and increased CNV amplitude. Both groups of subjects showed heightened alertness 2 and 3 hours post-drug. Amphetamine is not a simple stimulant of the central nervous system but can also act as a depressant.
Cerebral Dominance in Musicians and Nonmusicians
Authors: Bever Thomas G. , Chiarello Robert J.
Published: October 2006

Musically experienced listeners recognize simple melodies better in the right ear than the left, while the reverse is true for naive listeners. Hence, contrary to previous reports, music perception supports the hypothesis that the left hemisphere is dominant for analytic processing and the right hemisphere for holistic processing.
Isolated Brain Microvessels: A Purified, Metabolically Active Preparation from Bovine Cerebral Cortex
Authors: Brendel Klaus , Meezan Elias , Carlson Edward C.
Published: October 2006

A purified, metabolically active preparation of brain microvessels was isolated from bovine cerebral cortex by using a simple procedure involving mild disruption of the tissue by homogenization and trapping of the vessels on nylon sieves. This preparation permits in vitro metabolic and structural studies of small blood vessels.
Rural Health Care in Mexico?
Authors: Caedo Luis
Published: October 2006

A very large percentage of Mexico's population living in rural areas lacks resources for health care. Any new effort to provide such care must emphasize the health of the infant population because of the high percentage of infants in the country. Plans made at the national level have not been correlated with the conditions that exist in rural areas. For example, the majority of university programs are oriented toward urban medical practice, and the construction of more schools of medicine to solve the problem of doctors in rural areas is based on a mistaken premise. This problem has not been solved even in developed countries such as the United States where, as in Mexico, graduates in medicine migrate to the cities where optimal conditions are met for practicing the type of medicine for which they have been trained. Furthermore, it is both expensive and illogical to maintain urban doctors in rural areas where they cannot practice their profession for lack of resources; to do so is to deny the purpose of their education. Conventional schools of medicine, for reasons of investment and of structure, should teach only very selected groups of students who, on finishing their training, are fully capacitated to practice specialized medicine. A different system is required if we are to provide adequate health care in the rural communities. A system such as that described herein, adapted to the real need of rural communities, would avoid the necessity to create dysfunctional bureaucracies and would not destroy those institutions which have proved useful in the past. This study should be considered as one of the many pilot programs that should be initiated in order to determine the type of program that would best solve the problem of health care in rural Mexico. Other programs already being considered at the National Autonomous University of Mexico include the A36 plan of the Faculty of Medicine, now in operation; the work of C. Biro carried out in Netzahualcoyotl City (both focused on providing medical care to the urban poor); and the Open University program.

Unless an efficient program designed to meet the needs of rural communities is quickly put into operation, Mexico will, in the near future, be facing the same problems now confronting Southeast Asia.
The
trk
Proto-Oncogene Product: a Signal Transducing Receptor for Nerve Growth Factor
Authors: Kaplan David R. , Hempstead Barbara L. , Martin-Zanca Dionisio , Chao Moses V. , Parada Luis F.
Published: October 2006

The
trk
proto-oncogene encodes a 140-kilodalton, membrane-spanning protein tyrosine kinase (p140
prototrk
) that is expressed only in neural tissues. Nerve growth factor (NGF) stimulates phosphorylation of p140
prototrk
in neural cell lines and in embryonic dorsal root ganglia. Affinity cross-linking and equilibrium binding experiments with
125
I-labeled NGF indicate that p140
prototrk
binds NGF specifically in cultured cells with a dissociation constant of 10
-9
molar. The identification of p140
prototrk
as an NGF receptor indicates that this protein participates in the primary signal transduction mechanism of NGF.
Computations Underlying the Execution of Movement: A Biological Perspective
Authors: Bizzi Emilio , Mussa-Ivaldi Ferdinando A. , Giszter Simon
Published: October 2006

To execute voluntary movements, the central nervous system must transform the neural representation of the direction, amplitude, and velocity of the limb, represented by the activity of cortical and subcortical neurons, into signals that activate the muscles that move the limb. This task is equivalent to solving an "ill-posed" computational problem because the number of degrees of freedom of the musculoskeletal apparatus is much larger than that specified in the plan of action. Some of the mechanisms and circuitry underlying the transformation of motor plans into motor commands are described. A central feature of this transformation is a coarse map of limb postures in the premotor areas of the spinal cord. Vectorial combination of motor outputs among different areas of the spinal map may produce a large repertoire of motor behaviors.
Kinetic Characterization of Ribonuclease-Resistant 2′-Modified Hammerhead Ribozymes
Authors: Pieken Wolfgang A. , Olsen David B. , Benseler Fritz , Aurup Helle , Eckstein Fritz
Published: October 2006

The incorporation of 2′-fluoro- and 2′-aminonucleotides into a hammerhead ribozyme was accomplished by automated chemical synthesis. The presence of 2′-fluorouridines, 2′-fluorocytidines, or 2′-aminouridines did not appreciably decrease catalytic efficiency. Incorporation of 2′-aminocytidines decreased ribozyme activity approximately by a factor of 20. The replacement of all adenosines with 2′-fluoroadenosines abolished catalysis in the presence of MgCl
2
within the limits of detection, but some activity was retained in the presence of MnCl
2
. This effect on catalysis was localized to a specific group of adenines within the conserved single-stranded region of the ribozyme. The decrease in catalytic efficiency was caused by a decrease in the rate constant; the Michaelis constant was unaltered. The 2′-fluoro and 2′-amino modifications conferred resistance toward ribonuclease degradation. Ribozymes containing 2′-fluoro- or 2′-aminonucleotides at all uridine and cytidine positions were stabilized against degradation in rabbit serum by a factor of at least 10
3
compared to unmodified ribozyme.
Rules of Language
Authors: Pinker Steven
Published: October 2006

Language and cognition have been explained as the products of a homogeneous associative memory structure or alternatively, of a set of genetically determined computational modules in which rules manipulate symbolic representations. Intensive study of one phenomenon of English grammar and how it is processed and acquired suggests that both theories are partly right. Regular verbs (
walk-walked
) are computed by a suffixation rule in a neural system for grammatical processing; irregular verbs (
run-ran
) are retrieved from an associative memory.
Selective Inhibition of Leukemia Cell Proliferation by BCR-ABL Antisense Oligodeoxynucleotides
Authors: Szczylik Cezary , Skorski Tomasz , Nicolaides Nicholas C. , Manzella Livia , Malaguarnera Lucia , Venturelli Donatella , Gewirtz Alan M. , Calabretta Bruno
Published: October 2006

To determine the role of the BCR-ABL gene in the proliferation of blast cells of patients with chronic myelogenous leukemia, leukemia blast cells were exposed to synthetic 18-mer oligodeoxynucleotides complementary to two identified BCR-ABL junctions. Leukemia colony formation was suppressed, whereas granulocyte-macrophage colony formation from normal marrow progenitors was unaffected. When equal proportions of normal marrow progenitors and blast cells were mixed, exposed to the oligodeoxynucleotides, and assayed for residual colony formation, the majority of residual cells were normal. These findings demonstrate the requirement for a functional BCR-ABL gene in maintaining the leukemic phenotype and the feasibility of gene-targeted selective killing of neoplastic cells.
Distinct Alkaline Phosphatase in Serum of Patients with Lymphatic Leukemia and Infectious Mononucleosis
Authors: Neumann H. , Moran E. M. , Russell R. M. , Rosenberg I. H.
Published: October 2006

A distinct alkaline phosphatase (phosphatase N) was demonstrated in the serum of patients with acute lymphatic leukemia, chronic lymphatic leukemia, and infectious mononucleosis. This enzyme closely resembles that extracted from the thymus of mice with lymphoma or lymphatic leukemia, both in its electrophoretic mobility and its substrate specificity. The phosphatase N activity was related to the clinical state of patients with lymphatic leukemia and disappeared with recovery from infectious mononucleosis.
Cochlear Neurons: Frequency Selectivity Altered by Perilymph Removal
Authors: Robertson Donald
Published: October 2006

Removal of perilymph from the scala tympani of the guinea pig cochlea reversibly broadened the tuning curves of single spiral ganglion cells emanating from the basilar membrane. Thus, fluid continuity along the membrane is essential for normal cochlear function, in particular for sharp neural tuning curves. These data reveal a possible source of error in some estimates of basilar membrane motion and suggest a reappraisal of current concepts of the mechanism of sharp tuning in primary auditory nerve fibers.
Ozone Concentrations in New Jersey and New York: Statistical Association with Related Variables
Authors: Bruntz S. M. , Cleveland W. S. , Graedel T. E. , Kleiner B. , Warner J. L.
Published: October 2006

The concentrations of ozone at nine measurement sites in New Jersey and New York during the period 1 May through 30 September 1973 have been examined. Daily fluctuations in the ozone concentrations at any two sites are highly correlated. The concentrations are lower with low levels of solar radiation and also with high wind speed. The average ozone concentration shows only minor differences between weekdays and weekends, despite markedly different traffic patterns.
Mammalian Hepatic Lectin
Authors: Stockert Richard J. , Morell Anatol G. , Scheinberg I. Herbert
Published: October 2006

A rabbit hepatic protein that specifically binds asialoglycoproteins is also a lectin that agglutinates untreated human and rabbit erythrocytes and neuraminidase-treated erythrocytes from rat, mouse, and guinea pig. Both binding of asialoglycoproteins and agglutination of erythrocytes appear to involve reaction on the same active sites of the hepatic protein.
Cyclic Guanosine Monophosphate: Elevation in Degenerating Photoreceptor Cells of the C3H Mouse Retina
Authors: Farber Debora B. , Lolley Richard N.
Published: October 2006

As a result of an early deficiency in cyclic nucleotide phosphodiesterase activity, guanosine 3′,5′-monophosphate accumulates in retinal photoreceptor cells before they begin to degenerate. It is suggested that degeneration of the photoreceptor cells is related to an imbalance in their metabolism or function which is caused by the elevated levels of cyclic guanosine monophosphate.