bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Mechanism Accounting for Precise Immunoglobulin Domain Deletion in a Variant of MPC 11 Myeloma Cells
Authors: Kenter Amy L. , Birshtein Barbara K.
Published: October 2006

A variant of the MPC 11 cell line, M 311, produces a short immunoglobulin heavy chain. When compared with the parental γ2b heavy chain, M 311 was found to have a carboxyl terminal deletion comprising the C
H
3 domain. The COOH-terminal cyanogen bromide (CNBr) cleavage fragment of M 311 is identical to a corresponding segment of a parental heavy chain CNBr fragment, with the exception of a substitution of asparagine for lysine at the COOH-terminal residue. This observation enabled prediction of both the parental DNA sequence in this region and the genetic mechanism which generated the variant, a frameshift followed by premature termination. This hypothesis is supported by studies of the DNA sequence of the MPC 11 γ2b constant region gene.
Human α-Lactalbumin: Measurement in Serum and in Breast Cancer Organ Cultures by Radioimmunoassay
Authors: Kleinberg David L.
Published: October 2006

A sensitive and specific radioimmunoassay for human α-lactalbumin, a major milk protein, is described. Some normal men and women have detectable levels of α-lactalbumin in their blood. High values are found in nursing mothers and many patients with galactorrhea. α-Lactalbumin is found in some breast cancer organ cultures. In addition, α-lactalbumin output was stimulated by ovine prolactin in 2 of the 19 tumors studied.
Hemopoietic Stem Cells in Human Peripheral Blood
Authors: Barr Ronald D. , Whang-Peng Jacqueline , Perry Seymour
Published: October 2006

A population of lymphocytes, separable from the great majority by virtue of their larger size and their failure to exhibit the rosetting characteristics of thymus-dependent lymphocytes and bursa-equivalent cells, possess true pluripotentiality. On culture in vivo they proliferate and differentiate into erythrocytic, granulocytic, and megakaryocytic progeny. This may be the first clear demonstration of the primitive progenitor blood cell in man.
Melanoma Antigens That Produce Cell-Mediated Immune Responses in Melanoma Patients: Joint U.S.-U.S.S.R. Study
Authors: Gorodilova V. V. , Hollinshead A.
Published: October 2006

Melanoma extracts used in the U.S.S.R. for immunochemotherapy of melanoma patients are found to contain a glycolipoprotein that is very similar to the melanoma tumor-associated antigen used in the United States for skin tests.
Model for Disseminated Cutaneous Leishmaniasis
Authors: Kadivar Dariyoush M. H. , Soulsby E. J. L.
Published: October 2006

Leishmania
infection of a skin site with interrupted lymphatic drainage results in widespread cutaneous metastases. This model may provide a method for the study of disseminated cutaneous leishmaniasis in man.
Site of Conversion of Desoxycorticosterone Acetate to Progestin
Authors: Lazo-Wasem E. A. , Zarrow M. X.
Published: October 2006

The conversion of DCA to progestin
in vivo
, which has been shown in the case of the monkey and now the rat, indicates one possible mechanism by which progestin may occur in the male. In addition, these studies also show that, at least in the rodent, the adrenals and the kidneys are the sites of this conversion. Investigations on the conversion of DCA to progestin in other species, as well as studies on the release of progestin by tissue slices incubated with or without DCA, are currently in progress.
Data Processing for Scientists
Authors: Heumann Karl F.
Published: October 2006

This brief survey of integrated and electronic data processing has touched on such matters as the origin of the concepts, their use in business, machines that are available, indexing problems, and, finally, some scientific uses that surely foreshadow further development. The purpose of this has been to present for the consideration of scientists a point of view and some techniques which have had a phenomenal growth in the business world and to suggest that these are worth consideration in scientific data-handling problems.

To close, let me quote from William Bamert on the experience of the C. and O. Railroad once more (p. 121): "Frankly, we have been asked whether we weren't planning for Utopia—the implication being that everyone except starry-eyed visionaries knows that Utopia is unattainable. Our answer is that of course we are! Has anyone yet discovered a better way to
begin
program planning of this nature? Our feeling is that compromise comes early enough in the normal order of things."
Specificity of Neonatal, Androgen-Induced Imprinting of Hepatic Steroid Metabolism in Rats
Authors: Gustafsson Jan-Åke , Stenberg Åke
Published: October 2006

The specificity of the neonatal, androgen-induced, irreversible programming of hepatic steroid metabolism in the rat was investigated. 5α-Dihydrotestosterone propionate and estradiol benzoate were as efficient as testosterone propionate in inducing a male type of liver metabolism in the adult animal, whereas epitestosterone propionate, etiocholanolone propionate, and
o
,
p
′-DDT were practically inactive in this respect. These findings indicate that different mechanisms are involved in neonatal imprinting of hepatic steroid metabolism and in the well-known neonatal androgenic and estrogenic induction of persistent estrus and acyclic gonadotropin secretion.
Niche Shifts in Sunfishes: Experimental Evidence and Significance
Authors: Werner Earl E. , Hall Donald J.
Published: October 2006

Three species of sunfishes segregate ecologically when stocked together in small ponds. When each species is stocked separately in replicate ponds, it exhibits competitive release through increases in growth rate and average food size. Niche shifts are indicated by convergence of these species to the same food habits in the absence of competitors. These shifts are due to phenotypic (behavioral) plasticity. The significance of niche flexibility is related to seasonal patterns in resource availability.
HL-A LD (Lymphocyte Defined) Typing: A Rapid Assay with Primed Lymphocytes
Authors: Sheehy Michael J. , Sondel Paul M. , Bach Marilyn L. , Wank Rudolf , Bach Fritz H.
Published: October 2006

When human lymphocytes are cultured for 9 to 14 days with stimulating cells of a family member differing by a single HL-A haplotype they become "primed" to recognize specific HL-A LD (mixed lymphocyte culture) antigens. These primed lymphocytes respond specifically and rapidly when "restimulated" with cells of a person that contain the same LD antigens as those of the priming haplotype. Specific HL-A LD antigens can be detected within 24 hours by this primed LD typing.
Bioluminescent Countershading in Midwater Animals: Evidence from Living Squid
Authors: Young Richard Edward , Roper Clyde F. E.
Published: October 2006

Midwater squid respond to overhead illumination by turning on numerous downward-directed photophores; they turn off the photophores when overhead illumination is eliminated. The squid are invisible when the intensity of the photophores matches the intensity of the overhead illumination. These results strongly support the theory of ventral bioluminescent countershading.
Lysogeny in Pneumococci Freshly Isolated from Man
Authors: Bernheimer Harriet P.
Published: October 2006

Twelve strains of encapsulated pneumococci isolated from patients with pneumococcal disease were examined for the presence of bacteriophage. Four of the strains yielded phage lytic for a noncapsulated indicator strain of pneumococcus. Three of the newly isolated bacteriophages differ serologically from pneumococcus bacteriophages described previously. The ability to yield lytic phage was lost by two of the lysogenic pneumococcal strains on repeated subculture.
Elimination of the Sarcoma Genome from Murine Sarcoma Virus Transformed Cat Cells
Authors: Frankel Arthur E. , Haapala Daniel K. , Neubauer Richard L. , Fischinger Peter J.
Published: October 2006

Cat cells transformed by Moloney murine sarcoma virus contain virus-specific sequences in their RNA and DNA. Cloned, spontaneous revertant cell lines derived from clones of these cells had no evidence of the sarcoma genome in the cell RNA or DNA as judged by RNA-complementary DNA or DNA-complementary DNA hybridizations. This is apparently the first report of loss of a transforming genome in a revertant cell line.
β-D-Galactosidase Activity in Single Yeast Cells During Cell Cycle of
Saccharomyces lactis
Authors: Yashphe Jacob , Halvorson Harlyn O.
Published: October 2006

Single
Saccharomyces lactis
cells taken from a random population were assayed for β-D-galactosidase activity under a microscope equipped for fluorogenic measurements. The cells were also photographed, and enzymatic activity was correlated to the size of cell buds. A periodic pattern of enzyme synthesis was found during the cell cycle.
A Novel Means for Dealing with L-Canavanine, a Toxic Metabolite
Authors: Rosenthal Gerald A. , Dahlman D. L. , Janzen Daniel H.
Published: October 2006

L-Canavanine is a highly toxic L-arginine analog found in some leguminous seeds. Larvae of the bruchid beetle
Caryedes brasiliensis
, collected in Costa Rica, subsist solely on tissues of the mature seed of
Dioclea megacarpa
, which contains more than 8 percent L-canavanine by dry weight. The arginyl-tRNA synthetase of the bruchid beetle larvae discriminates between L-arginine and L-canavanine, and canavanyl proteins are not synthesized. In this way, bruchid beetle larvae avoid an adverse biochemical effect of L-canavanine.
Phosphorylated Sites In Substrates of Intracellular Protein Kinases: A Common Feature in Amino Acid Sequences
Authors: Williams Ross E.
Published: October 2006

Examination of the primary amino acid sequences surrounding phosphorylated sites in many intracellular phosphoproteins indicated that the phosphorylated hydroxyamino acid (either serine or threonine) is, in general, surrounded by amino acids having a positively charged side chain and, more specifically, is frequently separated from a basic amino acid (either lysine or arginine) by only one amino acid. Possible reasons for this common feature are discussed.
Vasoactive Intestinal Polypeptide: Abundant Immunoreactivity in Neural Cell Lines and Normal Nervous Tissue
Authors: Said Sami I. , Rosenberg Roger N.
Published: October 2006

Vasoactive intestinal polypeptide immunoreactivity is present in high concentrations in clonal lines of neuronal and glial origin. The central nervous system and sympathetic ganglia are also rich in the peptide. The findings suggest that this peptide, hitherto thought limited to the gastrointestinal tract, is widely distributed in neural tissue and may have broad physiological significance.
Lack of Protective Immunity Against Reinfection with Hepatitis C Virus
Authors: Farci Patrizia , Alter Harvey J. , Govindarajan Sugantha , Wong Doris C. , Engle Ronald , Lesniewski Richard R. , Mushahwar Isa K. , Desai Suresh M. , Miller Roger H. , Ogata Norio , Purcell Robert H.
Published: October 2006

Some individuals infected with hepatitis C virus (HCV) experience multiple episodes of acute hepatitis. It is unclear whether these episodes are due to reinfection with HCV or to reactivation of the original virus infection. Markers of viral replication and host immunity were studied in five chimpanzees sequentially inoculated over a period of 3 years with different HCV strains of proven infectivity. Each rechallenge of a convalescent chimpanzee with the same or a different HCV strain resulted in the reappearance of viremia, which was due to infection with the subsequent challenge virus. The evidence indicates that HCV infection does not elicit protective immunity against reinfection with homologous or heterologous strains, which raises concerns for the development of effective vaccines against HCV.
Tyrosine Phosphorylation of CD22 During B Cell Activation
Authors: Schulte Roberta J. , Campbell Mary-Ann , Fischer Wolfgang H. , Sefton Bartholomew M.
Published: October 2006

Ligation of the antigen receptor on B cells induces the rapid phosphorylation of tyrosine on a number of cellular proteins. A monoclonal antibody that recognized a tyrosine-phosphorylated cell surface protein that was present in activated B cells was generated. Amino acid sequence analysis showed that this 140-kilodalton protein was CD22, a B cell-specific cell surface glycoprotein and putative extracellular ligand of the protein tyrosine phosphatase CD45. Tyrosine phosphorylation of CD22 may be important in B cell signal transduction, possibly through regulation of the adhesiveness of activated B cells.
Porins in the Cell Wall of Mycobacteria
Authors: Trias Joaquim , Jarlier Vincent , Benz Roland
Published: October 2006

The cell wall of mycobacteria is an efficient permeability barrier that makes mycobacteria naturally resistant to most antibiotics. Liposome swelling assays and planar bilayer experiments were used to investigate the diffusion process of hydrophilic molecules through the cell wall of
Mycobacterium chelonae
and identify the main hydrophilic pathway. A 59-kilodalton cell wall protein formed a water-filled channel with a diameter of 2.2 nanometers and an average single-channel conductance equal to 2.7 nanosiemens in 1 M potassium chloride. These results suggest that porins can be found in the cell wall of a Gram-positive bacterium. A better knowledge of the hydrophilic pathways should help in the design of more effective antimycobacterial agents.
An Immunological Investigation of Human Pituitary Growth Hormone
Authors: Hayashida T. , Li Choh Hao
Published: October 2006

Growth hormone isolated from human pituitaries has been demonstrated to be a good antigen in the rabbit. With the rabbit antiserum to human somatotropin, it is possible to detect as little as 0.1 μg of the hormone by precipitin test. The antiserum was also capable of neutralizing the growth-promoting activity of human somatotropin.
Airborne Immunization against Tuberculosis
Authors: Cohn M. L. , Davis C. L. , Middlebrook G.
Published: October 2006

Inhalation of very small numbers of living attenuated (BCG) organisms and their multiplication in guinea pigs results in the development of acquired resistance against subsequent airborne infection with virulent tubercle bacilli. Different strains of BCG have differing capacities to immunize by this means.
Complement Fixation with a Mouse Tumor Virus (S.E. Polyoma)
Authors: Rowe Wallace P. , Hartley Janet W. , Brodsky Isadore , Huebner Robert J.
Published: October 2006

Complement fixation tests with tissue-culture antigens indicated that polyoma virus is serologically unrelated to a wide variety of known viruses; antibody developed uniformly in mice given virus intraperitoneally or intranasally and was found in normal animals of several mouse colonies but not in human beings.
Rigid Urethane Foams Based on Sorbitol Derivatives
Authors: Wilson Joseph E. , Fowler Raymond H.
Published: October 2006

Present commercial rigid foams are based on polyester raw materials. It has now been demonstrated that certain hydroxyl-terminated polyethers can be used satisfactorily as a major component of rigid urethane foams. These polyethers are hexafunctional materials prepared by reacting propylene oxide with sorbitol.
Zinc-65 in Foods and People
Authors: Perkins R. W. , Nielsen J. M.
Published: October 2006

Disposal of trace amounts of Zn
65
is made in the Columbia River via Hanford reactor effluent water. The subsequent utilization of river water for irrigation permits the concentration of this radioisotope in farm produce and its eventual deposition in man. The Zn
65
in irrigation water, in farm produce, and in individuals utilizing these materials has been measured.
Multiple
p
H Levels in Chromatograms
Authors: Bitancourt A. A. , Nogueira Alexandra P.
Published: October 2006

Lines of buffer solutions drawn longitudinally on chromatograms with a capillary pipette provide different levels of
p
H which affect the
R

f

values, color, fluorescence, and other properties of the chromatographed substances.
Biliary Excretion by the Rat of Bromsulfalein as a Conjugate of Glycine and Glutamic Acid
Authors: Combes Burton
Published: October 2006

Paper chromatograms of bile collected after the intravenous administration of bromsulfalein to rats reveal four distinct bromsulfalein bands. One migrates with the same
R

f

as standard bromsulfalein; the other three move less fast. The major band, which accounts for 71.3 percent of the injected bromsulfalein, appears to be a conjugate of bromsulfalein with glycine and glutamic acid.
Requirements for Floral Initiation of Los Angeles
Xanthium
Authors: Carpenter Bruce H. , Lincoln Richard G.
Published: October 2006

Cocklebur from the Los Angeles area was found to require more extensive short-day treatment for floral initiation than plants of the same species from the Chicago region. Data obtained by grafting the two regional types of cocklebur indicate that the leaves of the Los Angeles
Xanthium
produce a comparatively low amount of the flowering stimulus.
Function of Giant Mauthner's Neurons in the Lungfish
Authors: Wilson Donald M.
Published: October 2006

Unit spikes were recorded from the spinal cord of the lungfish
Protopterus
and were identified with Mauthner's axon. With these spikes occurred nongraded tail flips suggesting startle responses. The tail flip and the giant spike resulted from certain forms of jarring and prodding. The conduction velocity for the slightly myelinated. 45 μ diameter fibers was 18.5 m/sec.
Biochemical Basis of Mating in Yeast
Authors: Brock Thomas D.
Published: October 2006

One mating type of the yeast
Hansenula wingei
possesses a specific protein on its cell surface which is complementary to a specific polysaccharide on the cell surface of the opposite mating type. The initial phase of mating in which cells of opposite types combine is therefore analogous to a reaction between an antibody and a polysaccharide antigen.
Distribution of Radioactivity in Wheat Plants Grown in the Presence of Strontium-90
Authors: Lee C. C.
Published: October 2006

Thatcher wheat grown in soil to which Sr
90
had been added showed that accumulation of radioactivity in the kernels was about one-tenth the accumulation in leaves and stems. Experimental milling of the kernels gave brans with the largest amounts and flours with the least amounts of activity, the Sr
90
concentrations being related practically linearly to the weights of total ash in the various milling products.
Nucleoprotein Constituents Stimulating Growth in Tissue Culture: Active Protein Fraction
Authors: Kutsky R. J.
Published: October 2006

A new method has been developed for removing the nucleic acid portion of the nucleoprotein fraction which stimulates growth in tissue culture. Biological activity resides in the purified protein fraction, while the high-polymer nucleic acid fraction is inert. The active protein fraction contains extractable lipids which have no effect on the biological activity.
Color Reaction for Certain Amino Acids, Amines, and Proteins
Authors: Keeler Richard F.
Published: October 2006

Proteins, certain amino acids, and amines undergo a potentially useful color reaction. The reaction involves the apparent formation of pyrroles when the compounds are allowed to react with acetonylacetone. The pyrroles yield colored complexes on coupling with
p
-dimethylaminobenzaldehyde. This report describes the specificity and possible uses of this reaction in colorimetric measurements and in paper chromatographic detection of these compounds.
Nature of Colchicine Resistance in Golden Hamster
Authors: Midgley A. Rees , Pierce Barry , Dixon Frank J.
Published: October 2006

The unresponsiveness of the golden hamster to colchicine has been shown to be the result of a resistance of individual cells to the drug. This resistance makes it possible to use hamsters with heterotransplanted tumors for testing the in vivo effects of colchicine on the tumors, with no toxic host reactions.
Magnitude of Reinforcement and Consummatory Behavior
Authors: Davis John D. , Keehn J. D.
Published: October 2006

The rates at which white rats licked saline, sucrose, and saccharin solutions, respectively, were measured by cumulative recording of tongue contacts with the solution in question. The local rate of licking was constant for all solutions, but differences in the distribution of sustained periods of licking were related to the type and concentration of the fluid consumed.
Isolation of Several Peptides with Relaxin Activity
Authors: Frieden Edward H. , Stone Naomi R. , Layman Noel W.
Published: October 2006

When a relaxin preparation was subjected to counter-current distribution for 355 transfers in a butanol-trichloroacetic acid system, significant biological activity was found over a band appreciably wider than was expected for a single component. By refractionation of the active band, three peptides with relaxin activity were isolated.
Use of Phosphorus-32 in Microassay for Nucleic Acid Synthesis in
Escherichia coli
Authors: Hanawalt Phil
Published: October 2006

A method was developed to facilitate studies of ribonucleic acid and deoxyribonucleic acid synthesis in growing bacterial cultures of small volume. The nucleic acid fractions were separated by means of a modified Schmidt-Thannhauser procedure applied to micro quantities of P
32
-labeled cells collected on membrane filters. The validity and usefulness of the method are discussed.
Learning Differences in Two Separated Lines of Mice
Authors: Denenberg Victor H.
Published: October 2006

Significant differences in conditioning and response topography were obtained with two lines in C57BL/10 mice, suggesting the occurrence of a behavioral mutation. It is suggested that the two lines be classified as substrains. The two substrains would appear to be useful in experiments on the genetics of behavior.
Incorporation of Tritiated Thymidine into Meiotic Chromosomes
Authors: Lima-de-Faria A.
Published: October 2006

In pachytene nuclei of
Melanoplus
the heterochromatin of the sex chromosome was found to synthesize DNA at a different time than the autosomal euchromatin.
Hybridization of
Salmonella
Species by Mating with
Escherichia coli
Authors: Baron L. S. , Spilman W. M. , Carey W. F.
Published: October 2006

A number of species of
Salmonella
were fertile at low frequency as recipients in crosses with
Escherichia coli
, as evidenced by the isolation of lactosepositive hybrids possessing the
Salmonella
antigenic structure. A hybrid from an initial mating, when crossed again with
E. coli
, behaved then as a high-frequency recipient strain.
Photosensitive Site in Lettuce Seeds
Authors: Ikuma Hiroshi , Thimann Kenneth V.
Published: October 2006

Red light is effective only in promoting germination of Grand Rapids lettuce seeds, and far-red light is effective only in inhibiting it, when the hypocotyl half of the seed is exposed to the light. It is concluded that the photoreceptor is probably located in the tip of the hypocotyl.
Mechanism of Enzyme Inhibition by Phosphate Esters
Authors: Bernhard Sidney A. , Orgel Leslie E.
Published: October 2006

A theory for the rapid specific reaction of certain phosphorous-containing esters with many proteolytic enzymes based on the ability of phosphorous to form one additional bond relative to carbon is presented. A stable tetrahedral phosphate ester is compared with a labile tetrahedral orthocarbonyl ester and a relatively stable pentagonal enzyme-phosphate ester complex is compared with a pentagonal enzyme-carbonyl substrate complex. The latter complex is assumed to be the transition state in the enzyme-catalyzed reaction. If the theory is correct, it opens up the possibility of studying intermediates and transition states from the known structures of chemical inhibitors.
Occultation of the Bright Star Regulus by Venus
Authors: Hynek J. Allen
Published: October 2006

This occultation was observed and timed visually early in the afternoon of 7 July, in Madrid, Spain. The duration of the occultation was 11 minutes, 4.4 seconds, and mid-occultation occurred at 14 hours, 25 minutes, 9 seconds U.T. Over 600 individual photographs, which define the relative positions of Venus and Regulus, were obtained.
Competitive Antagonism between Kinetin and 8-Azaguanine in
Polytoma uvella
Authors: Moewus F.
Published: October 2006

The enhancement of mitotic activity by kinetin is proportional to the dosage from 0.003 to 0.03 μg/ml. This effect is competitively antagonized by 8-azaguanine. The suppression can be reversed by a fresh supply of kinetin.
Titration of the Protein Paramyosin
Authors: Johnson William H. , Kahn Joseph S.
Published: October 2006

The titration curve of an aqueous solution of crystalline paramyosin shows a unique buffering zone which can be attributed to a shift in the
pK
of its glutamic acid residues. A possible explanation of this phenomenon on the basis of the presence of polyanionic segments in the molecule is discussed.
Molting of Preadult Nematodes of the Genus
Paratylenchus
Stimulated by Root Diffusates
Authors: Rhoades H. L. , Linford M. B.
Published: October 2006

The nonfeeding preadult larvae of the plant-parasitic nematodes,
Paratylenchus projectus
and
P. dianthus
, survive in moist soil during long periods in the absence of host plants. In water, only small percentages molt to the adult stage. In root diffusates from some but not all plants, nearly all of them molt.
Stimulation of Amino Acid Transport in Isolated Diaphragm by Growth Hormone Added in vitro
Authors: Kostyo J. L. , Hotchkiss J. , Knobil E.
Published: October 2006

The influence of the pituitary on the transport of α-aminoisobutyric acid-1-C
14
into the cells of isolated rat diaphragm was investigated. Hypophysectomy results in a lower-than-normal rate of α-aminoisobutyric acid-1-C
14
penetration into muscle. Adding either simian or bovine growth hormone preparations to the incubation medium in concentrations of 2.5 to 25 μg/ml of medium resulted in a doubling of the α-aminoisobutyric acid-1-C
14
penetration rate. The stimulatory effect was minimized when the hormone concentration was reduced to 0.25 μg/ml of medium.
Cytopathic Effect of Canine Distemper Virus in Tissue Culture
Authors: Karzon David T. , Bussell Robert H.
Published: October 2006

A characteristic cytopathic effect was obtained with canine distemper virus (Onderstepoort strain) propagated in chick embryo fibroblast monolayer tissue culture. In limiting dilutions the lesions were focal. The titer at the 20th tissue culture passage was approximately 10
5
TCD
50
/ml. Cytopathogenicity was specifically inhibited by distemper immune serum. Minute plaques were produced under agar overlay.
Electronmicroscopy of Dental Calculus
Authors: Gonzales F. , Sognnaes R. F.
Published: October 2006

Electron microscopy of ultrathin osmium-fixed sections of dental calculus, cut with a diamond knife without prior decalcification, revealed densely mineralized areas entrapping many degenerating microorganisms, within which were deposited similarly electron-dense crystals. Two principal forms of crystals were found, the predominant type being of the same order of magnitude and shape as those found in bone, and showing the typical characteristics of apatite in selected area electron diffraction patterns.
Determination of the Earth's Gravitational Field
Authors: O'Keefe John A.
Published: October 2006

Brenner
et al
. have pointed out that spurious variations may be introduced into computation of satellite orbits by a combination of the use of osculating elements and a maldistribution of the observations. They suggest that this circumstance is the source of the eccentricity variations in the Vanguard I orbit which have been attributed to the third zonal harmonic. This criticism is based on a misunderstanding of the Vanguard orbit and tracking programs. The source materials for our study of the third zonal harmonic were not osculating elements, and the observations were in fact uniformly distributed around the Vanguard I orbit.
Zinc-65 and Zirconium-95 in Food
Authors: Van Dilla Marvin A.
Published: October 2006

Zinc-65 has been found in small amounts in muscle and liver samples obtained from cattle raised in Nevada, and also in commercial hamburger and beef liver from the southwestern area. Zirconium-95 and niobium-95 were found in the liver samples but not in the muscle or hamburger. A trace of zinc-65 was detected in milk but none in people.
Distribution of Labeled Carbon in Reef-Building Corals with and without Zooxanthellae
Authors: Goreau T. F. , Goreau N. I.
Published: October 2006

The uptake and distribution of carbon-14 in two reef-building corals,
Manicina areolata
and
Montastrea annularis
, were studied by radioautographic methods. Experiments on colonies with and without zooxanthellae were run in light and in darkness. We suggest that corals cannot derive any effective nutrition from their zooxanthellae, and that the physiological response of corals to the presence of zooxanthellae is due to the secretion of trace amounts of vitamin-like or hormone-like substances by the algal symbionts, and not to their food value per se.
Esters Produced by
Chalaropsis thielavioides
Authors: Collins Ralph P. , Morgan Max E.
Published: October 2006

Chalaropsis thielavioides
, a filamentous fungus. produces a characteristic ester-like aroma on potato dextrose broth. By gas-liquid chromatographic techniques, the major aroma-producing substances have been identified as isobutyl and ethyl acetate. Lesser amounts of isoamyl acetate, ethanol, and methanol were also present.
Epinephrine, Norepinephrine, and Acetylcholine as Conditioned Stimuli for Avoidance Behavior
Authors: Cook Leonard , Davidson Arnold , Davis Dixon J. , Kelleher Roger T.
Published: October 2006

Conditioned leg-flexion responses in dogs were developed with electric shock as an unconditioned stimulus and intestinal stimulation or the effects of injections of various drugs as conditioned stimuli. It is concluded that physiological effects can play a role in the development and maintenance of conditioned avoidance behavior.
Blood Types in Fur Seals
Authors: Fujino Kazuo , Cushing John E.
Published: October 2006

Individual variations exist in the erythrocyte antigens of fur seals (
Callorbinus ursinus
).
Spore Germination and Emergence of
Bacillus megaterium
Authors: Levinson Hillel S. , Wrigley Alan S.
Published: October 2006

Bacillus megaterium
spores have a characteristic polar knob and equatorial ridge, or groove. During germination, the spore case appears to split along this ridge, and thus allows the new cell to emerge. Mechanically ground spores also split along this ridge, one part of the spore case being hinged to the other, the ridge being evident along a free edge. The equatorial ridge appears to be an area of susceptibility to mechanical pressures and, perhaps, in normal germination, to enzymic action as well.
Prehistoric Copper Objects from Western Mexico
Authors: Meighan Clement W.
Published: October 2006

A series of Pre-Columbian copper artifacts from Nayarit, Mexico, is analyzed. Evidence of deliberate alloys is negative, but the specimens are important as early examples of metal working in Mesoamerica.
Scintillation Counting of Beta Activity on Filter Paper
Authors: Funt B. Lionel , Hetherington Arlene
Published: October 2006

Scintillation counting of beta activity on filter paper, with monoisopropylbiphenyl as a solvent of low volatility, was investigated. The method is attractive since no sample preparation is involved, and the activities are measured directly on the filter paper wetted with the scintillator solution. A linear dependence of counting rate on total activity was found for iodine-131, phosphorus-32, sodium-22, and carbon-14, and counting efficiencies were determined.
Induction of Staminate Flowers on Gynoecious Cucumbers with Gibberellin A
3
Authors: Peterson C. E. , Anhder LaMoine D.
Published: October 2006

Staminate flowers induced on gynoecious plants permitted the establishment and increase of inbred lines bearing only pistillate flowers. This method of altering sex expression has practical applications in developing F
1
hybrids, and is useful in studying the physiology and genetics of sex expression.
Effects of Deprivation and Scheduling on Water Intake in the White Rat
Authors: Kessen William , Kimble Gregory A. , Hillmann Beverly M.
Published: October 2006

Two studies are presented to demonstrate that the consummatory behavior of drinking in the rat is under the control of duration of water deprivation and that intake after deprivation is related to variation in the scheduling of the animals' opportunities for drinking.
Molecular Characterization of Helix-Loop-Helix Peptides
Authors: Anthony-Cahill Spencer J. , Benfield Pamela A. , Fairman Robert , Wasserman Zelda R. , Brenner Stephen L. , Stafford Walter F. , Altenbach Christian , Hubbell Wayne L. , DeGrado William F.
Published: October 2006

A class of regulators of eukaryotic gene expression contains a conserved amino acid sequence responsible for protein oligomerization and binding to DNA. This structure consists of an arginine- and lysine-rich basic region followed by a helix-loop-helix motif, which together mediate specific binding to DNA. Peptides were prepared that span this motif in the MyoD protein; in solution, they formed α-helical dimers and tetramers. They bound to DNA as dimers and their α-helical content increased on binding. Parallel and antiparallel four-helix models of the DNA-bound dimer were constructed. Peptides containing disulfide bonds were engineered to test the correctness of the two models. A disulfide that is compatible with the parallel model promotes specific interaction with DNA, whereas a disulfide compatible with the antiparallel model abolishes specific binding. Electron paramagnetic resonance (EPR) measurements of nitroxide-labeled peptides provided intersubunit distance measurements that also supported the parallel model.
Rates of Submergence of Coastal New England and Acadia
Authors: Lyon C. J. , Harrison W.
Published: October 2006

Altitudinal and carbon-14 age determinations of in-place
Pinus strobus
stumps of drowned forests at Odiorne Point, N.H., and Grand Pré and Fort Lawrence, Nova Scotia, yield apparent average rates of submergence of 3.1, 14.5, and 20.3 feet per 1000 C
14
years, respectively. Rate differences are assessed in terms of eustatic rise of sea level, crustal movements, and tidal effects.
"Second Emerson Effect" in the Hill Reaction of
Chlorella
Cells with Quinone as Oxidant
Authors: Govindjee Rajni , Thomas Jan B. , Rabinowitch Eugene
Published: October 2006

The second Emerson effect can be observed not only in photosynthesis but also in the photoreduction of quinone by
Chlorella
cells. This shows that this effect is not due to respiration and is not associated with the carbon dioxide-reducing phase of photosynthesis. Peaks at 650 and 670 mμ in the action spectra of this effect, in the case of quinone reductions as well as in that of photosynthesis in
Chlorella
, show that light absorbed by chlorophyll
b
as well as that absorbed by chlorophyll
a
670 can effectively supplement far-red light (> 680 mμ) in both reactions; light absorbed by chlorophyll
a
680 cannot do so.
Relating a Component of Physiological Nystagmus to Visual Display
Authors: Gaarder Kenneth
Published: October 2006

A transactional position suggests the hypothesis that there should be changes in the fine eye movements of a fixating subject if the fixated visual display is altered. It is shown that the mean saccadic eye movements are unequivocally different with different positions of the stimulus within the visual field.
Transfer of Maternal Calcium to the Offspring via the Milk
Authors: Bronner Felix
Published: October 2006

By measuring the specific activities of milk and of maternal and filial long bones 3 months after calcium-45 had been given to the then nonpregnant mothers, it was found that the magnitude of the contribution of the maternal calcium stores to milk formation is similar to the contribution to the bone calcium of the offspring, that is, 10 to 15 percent of either milk calcium or filial calcium is maternal in origin.
Long-Range Detection of French Nuclear Tests of 1960
Authors: Patterson R. L. , Lockhart L. B.
Published: October 2006

With a relatively small number of strategically located ground-level air-filter stations, it has been possible to detect the presence of radioactive debris from the French nuclear test of February 1960 at a great distance from the test site, and to obtain data on the time of arrival of this debris and the extent of its north-south spread.
Respondent Salivary Conditioning during Operant Lever Pressing in Dogs
Authors: Shapiro Martin M.
Published: October 2006

The lever-pressing response of four dogs was reinforced with food on a 2-minute fixed-interval schedule, with salivation also being recorded continuously. Respondent salivary conditioning was found to occur during operant lever-pressing conditioning, the occurrences of the two conditioned responses being positively correlated.
Perception of Apparent Motion in the Common Toad
Authors: Kaess Walter , Kaess Francis
Published: October 2006

A simple and inexpensive apparatus makes possible the feeding of nonliving objects to the toad. The device is used to demonstrate the perception of apparent or "induced" motion. Two methods are successful: (i) toad and food moving together at a constant velocity in a stationary environment; (ii) toad and food stationary with the environment moving. The phenomena are similar to those found in human beings.
Acetylcholinesterase Regeneration in Peripheral Nerve after Irreversible Inactivation
Authors: Koenig Edward , Koelle George B.
Published: October 2006

The return of acetylcholinesterase activity was studied in several cholinergic structures in the cat after irreversible inactivation by di
iso
propylfluorophosphate. It was found that enzymic activity returned uniformly along the hypoglossal and cervical sympathetic nerve trunks. No evidence for somatoaxonal convection of enzyme was obtained.
Radiation Flavor—Fact or Fancy
Authors: Drake Maurice P. , Kroll Beverley J. , Pilgrim Francis J.
Published: October 2006

Experimental results indicate that sensory evaluations in different laboratories give equivalent results if standardized procedures and a standard sample are used. Conflicting results concerning the flavor of irradiated foods are due largely to different methods of evaluation and to incorrect interpretation of results. Unusual flavor due to irradiation should be considered different, not necessarily objectionable.
Activation-Induced Ubiquitination of the T Cell Antigen Receptor
Authors: Cenciarelli Cristina , Hou Damon , Hsu Kou-Ching , Rellahan Barbara L. , Wiest David L. , Smith Harry T. , Fried Victor A. , Weissman Allan M.
Published: October 2006

The ζ subunit of the T cell antigen receptor (TCR) exists primarily as a disulfide-linked homodimer. This receptor subunit is important in TCR-mediated signal transduction and is a substrate for a TCR-activated protein tyrosine kinase. The ζ chain was found to undergo ubiquitination in response to receptor engagement. This posttranslational modification occurred in normal T cells and tumor lines. Both nonphosphorylated and phosphorylated ζ molecules were modified, and at least one other TCR subunit, CD3 δ, was also ubiquitinated after activation of the receptor. These findings suggest an expanded role for ubiquitination in transmembrane receptor function.
Expression of C4 on Human Lymphoid Cells and Possible Involvement in Immune Recognition Phenomena
Authors: Ferrone Soldano , Pellegrino Michele A. , Cooper Neil R.
Published: October 2006

Immunochemical studies revealed the presence of the fourth component of complement (C4) on surfaces of human lymphoid cells. Antiserums to C4 inhibited the mixed lymphocyte reaction and the mitogenic response to phytohemagglutinin, suggesting a role for membrane-associated C4 in the afferent phase of immune recognition phenomena.
Facilitation of Infection of Monkey Cells with Poliovirus "Ribonucleic Acid"
Authors: Dubes George R. , Klingler Eugene A.
Published: October 2006

The plaque titer of poliovirus "ribonucleic acid" on monkey kidney cells cultured in vitro is greatly increased by depleting these cells of calcium and treating the "ribonucleic acid" inoculum with a suspension of any one of several poorly water-soluble substances before inoculation. These undissolved substances apparently facilitate infection by serving as solid vehicles for the "ribonucleic acid."
Selective Viral and Rickettsial Serum Antibody Absorption by a Chromatographic Column
Authors: Brown Norman K.
Published: October 2006

Serum antibodies behave as cations at neutral
p
H and thus have low affinity for cellulose anion-exchange columns. Antigens of small size derived from adenovirus, influenza virus, and typhus rickettsiae, however, readily adsorbed to such columns. These adsorbed antigens specifically removed antibodies from antisera. This simple method permits antibody absorption by antigens ordinarily sedimented with difficulty.
Delayed Alternation in Hemicerebrectomized Monkeys
Authors: Kruper Donald C. , Koskoff Yale David , Patton R. A.
Published: October 2006

Monkeys subjected to extensive unilateral brain extirpation learned a delayed alternation task, although their rates of learning were significantly lower than those of a control group of normal animals. Visual field defects did not seem to account for the deficit.
Fluorescence of Photosynthetic Organisms at Room and Liquid Nitrogen Temperatures
Authors: Brody Marcia , Linschitz Henry
Published: October 2006

Fluorescence spectra of algae and higher plants show two bands, ascribable to monomer and aggregate forms of chlorophyll. At low temperature, the long-wavelength emission is greatly enhanced and often appears as a new band. Photosynthetic bacteria, on the other hand, show no new bands at low temperature, within the spectral coverage and sensitivity of these measurements. A green fluorescence is also found in algae, which we attribute to carotenoids.
Use of a Computer to Evaluate Alternative Insecticidal Programs
Authors: Watt Kenneth E. F.
Published: October 2006

A simple numerical routine which mimics the effects of density-dependent factors and weather has been used to simulate insect pest population trends without control, and with a variety of insecticidal procedures. Results of the analysis suggest that apparent benefits from spraying are illusory, since spraying elicits homeostatic response by the pest population.
Ion Uptake by Living Plant Roots
Authors: Walker John M. , Barber Stanley A.
Published: October 2006

By taking daily autoradiographs of a uniformly labeled soil in which plants are growing, patterns of actual ion uptake from the soil can be established. This technique can be used to study such influences on ion uptake as that of plant species ion diffusion, moisture and temperature stresses, and different physical, chemical, and biological properties of the soil.
Fallout from Nuclear Detonations of February and April 1960
Authors: Kuroda P. K. , Hodges H. L. , Moore H. E.
Published: October 2006

A sharp increase in the ratio of strontium-89 to strontium-90 in rain was observed at Fayetteville, Arkansas, after the French nuclear detonations of February and April 1960. Experimental data obtained suggest the possibility that part of the debris from atom bombs detonated in the tropical region may enter the stratosphere.
Electron Microscopy and Autoradiography
Authors: George L. A.
Published: October 2006

The combined techniques of electron microscopy and autoradiography were used for the purpose of differentiating radioactive from nonradioactive particles collected on membrane filters. Newer methods of processing the membrane filters and applying the nuclear emulsion have resulted in an improvement in the qualitative nature of the procedure.
On the Anomalous Activity of Thyroxin Analogs in Tadpoles
Authors: Frieden Earl , Westmark G. Wayne
Published: October 2006

The abnormally high thyroxin-like activity of certain thyroxin analogs is due to the use of the unique test route of immersion. When thyroxin, triiodothyronine, and their propionic and acetic acid analogs are tested by injection into the tadpole, their activities are more comparable to activity levels established in rat and man.
Recording of Single Unit Activity in Isolated Central Nervous Tissue
Authors: Ames Adelbert , Gurian Bennett S.
Published: October 2006

The retina and attached segment of optic nerve isolated from the rabbit were maintained in a functioning state in vitro. Microelectrodes, introduced into the nerve, recorded unit discharges in response to light stimuli. The characteristics of these evoked discharges are described.
Strontium-90 and Cesium-137 in North American Milk
Authors: Kulp J. L. , Schulert A. R. , Hodges E. J. , Anderson E. C. , Langham W. H.
Published: October 2006

The strontium-90 and cesium-137 concentrations in powdered milk in North America vary roughly with the specific activity of rain. The Sr
90
/Cs
137
ratios in over 800 powdered milk samples taken from 60 stations in North America from 1957-60 have a standard deviation of only 44 percent.
Zinc-65 in Marine Organisms along the Oregon and Washington Coasts
Authors: Watson D. G. , Davis J. J. , Hanson W. C.
Published: October 2006

The concentration of zinc-65 in marine animals and plants near the mouth of the Columbia River is presented. Amounts of radiozinc found in the biota diminished rapidly with the distance from the river mouth. The highest levels were found in plankton, algae, and mollusks. Of the human foods, oysters exhibited the highest levels.
Estimation of Total Body Fat from Potassium-40 Content
Authors: Anderson Ernest C. , Langham Wright H.
Published: October 2006

A brief review is given of the development of methods for the determination of total body potassium by whole-body scintillation counting and of studies to establish the utility of body potassium as a measure of gross body composition including fat.
Evoked Cortical Activity from Auditory Cortex in Anesthetized and Unanesthetized Cats
Authors: Kiang Nelson Yuan-sheng , Neame John H. , Clark Louise F.
Published: October 2006

Evoked electric responses of the auditory cortex of unanesthetized cats were studied by averaging techniques which enable us to detect responses in high-level background activity without sacrificing bandwidth. The results suggest that previous studies on evoked responses from behaving animals that are based upon ink-written electroencephalographic displays were chiefly concerned with a set of response components that differ from the classical evoked potentials in anesthetized animals.
Harmonic Oscillation as Model for Cortical Excitability Changes with Attention in Cats
Authors: Freeman Walter J.
Published: October 2006

A single shock to the prepyriform cortex with implanted electrodes caused a damped, sinusoidal oscillation in potential. The root-mean-square amplitudes of potentials evoked by short trains of stimuli, when plotted against the frequency of stimulation, fitted the equation for forced harmonic oscillation when the cat was attentive to the stimuli.
Long-Term Nontoxic Support of Animal Life with Algae
Authors: Bowman Russel O. , Thomae Fred W.
Published: October 2006

One 40-g male albino mouse was kept in good health for 66 days in a chamber containing an algal photosynthetic gas exchanger. Carbon dioxide was well controlled, oxygen was slowly increased, and nitrogen was decreased in the chamber. Photosynthesis can support life in a hostile environment for extended periods of time.
Critical Factors in Successful Recovery of Rous Sarcoma Virus from Turkey Tumors
Authors: Bergs Victor V. , Groupé Vincent
Published: October 2006

Studies of tumor cell cultures with antiviral antibody showed that most of the cell-associated virus and viral antigen were found at the cell membrane and were thus accessible to the effect of neutralizing antibody. Humoral antibody present in tumor tissue neutralized cell-associated virus in vivo and thus rendered the tumor cells temporarily noninfectious. When these cells were grown in vitro in the absence of antibody, virus eventually reappeared. However, the time of reappearance, amount of virus produced, and persistence of virus in such cultures depended upon the amount of virus used to produce the tumor.