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CreatorTitleDescriptionSubjectDate
51 Seger, JonConditional relatedness, recombination, and the chromosome numbers of insectsIf two polymorphic loci are out of phase equilibrium, a homozygote at one of these loci is more highly related to its kin, at the other locus, than is an equivalent heterozygote. As a result, selection can favor (1) phenotypic responses to relative heterozygosity, and (2) increased recombination bet...Coefficients of relatedness; Conditional relatedness1983
52 Blair, David F.Metal centers of cytochrome c oxidase: structures and interactionsStudies directed toward the elucidation of the structures of the metal centers in cytochrome c oxidase are reviewed. Progress towards an understanding of the interactions between these centers and their spatial distributions within the protein will also be presented. Our studies are based primarily...1983
53 Olivera, Baldomero M.; Gray, William RobertConotoxin MI: disulfide bonding and conformational statesThe toxic peptide from Conus magus venom (conotoxin MI) is a 14-amino acid peptide (McIntosh, M., Cruz, L. J., Hunkapiller, M. W., Gray, W. R., and Olivera, B. M. (1982) Arch. Biochem. Biophys. 218, 329-334) which inhibits the acetylcholine ceptor. In this work we have confirmed the primary structu...Conotoxins; Disulfide bonding; Venom; Conus magus1983
54 Olivera, Baldomero M.Bacteriophage Mu DNA replication in vitroAn in vitro system for bacteriophage Mu DNA replication using lysates on cellophane discs is described. Mu replication was monitored by DNA hybridization. Using a thermoinducible Mu Iysogen, 30-50% of all DNA synthesis in vitro was Mu-specific.Bacteriophage Mu1983
55 Bastiani, MichaelPathfinding by neuronal growth cones in grasshopper embryos I. Divergent choices made by the growth cones of sibling neuronsWe are interested in how the growth cones of identified neurons navigate in the central nervous system of the grasshopper embryo. The behavior of identified growth cones was observed as a function of developmental time by (i) periodically removing embryos from synchronized clutches of eggs and (i...Neuropil; Axonal; Cell1983
56 Coley, Phyllis D.Uprooting and snapping of trees: structural determinants and ecological consequencesThe influence of mechanical and architectural properties of trees on growth rates, mortality rates, and relative probabilities of snapping and uprooting were examined on Barro Colorado Island, Republic of Panama. Of 310 fallen trees, 70% snapped, 25% uprooted, and 5% broke off at ground level. Stepw...Snapping; Uprooting1983
57 Bastiani, MichaelLoss of axons in the cat optic nerve following fetal unilateral enucleation: an electron microscopic analysisBetween the 48th day of gestation (E-48) and maturity, the number of axons in the cat optic nerve is reduced by approximately 50%. On the basis of an electron microscopic assay, the axon population of the E-48 nerve was estimated to be 328,000. In contrast, estimates from two normal adults were 159,...Ganglion cell death; Retinofugal projection; Retinal ganglion cell axons1983
58 Beckerle, Mary C.Analysis of the roles of microtubules and actin in erythrophore intracellular motilityThe Holocentrus erythrophore, a red pigment cell, represents a model system for the study of organized intracellular transport. We have investigated the possibility that microtubules and actin are integral components of the pigment translocating motility machine.Actin; Actomyosin; Erythrophore; Pigment1983
59 Coley, Phyllis D.Intraspecific variation in herbivory on two tropical tree speciesLevels of herbivory on young and mature leaves were determined for two tree species, Trichilia cipo (Meliaceae) and Cecropia insignis (Moraceae), in a lowland rain forest of Panama. Saplings of both species were studied in light gaps, and in addition, Trichilia was studied in the understory.Cecropia insignis; Trichilia cipo; Herbivory; Intraspecific variation; Panama; Temporal distribution; Treefall gaps; Tropical forest; Understory1983
60 Sperry, John S.Observations on the structure and function of hydathodes in Blechnum lehmaniiThe fronds of many ferns in the Polypodiaceae (Ogura, 1972) and Cyatheaceae (Weiler, cited in Lippmann, 1925) possess swollen vein endings associated with specialized adaxial epidermal cells. Their structure is similar in all ferns (Gardiner, 1883; Potonie, 1892; Poirault, 1893; Goebel, 1930; Gutten...Hydathodes; Blechnum lehmannii; Root pressure; Secretion1983
61 Sperry, John S.Anatomy of the palm Rhapis excelsa, IX. Xylem structure of the leaf insertionSTEMS OF PERENNIAL PLANTS, particularly trees, represent a considerable investment in biomass. Trees can survive even under the most adverse conditions, but only if the hydraulic integrity of the stem is preserved. A very important and vulnerable part of the stem is the xylem. As water is pulled int...Palm stems; Palm stem anatomy; Palm leaves; Leaf insertion; Vessel network; Vessel-length distribution; Primary vascular stem tissue; Hydraulic architechture; Water column1983
62 Bastiani, MichaelPathfinding by neuronal growth cones in grasshopper embryos: II. Selective fasciculation onto specific axonal pathwaysIn the previous paper (Raper, J. A., M. Bastiani, and C. S. Goodman (1983) J. Neurosci. 3: 20-30) we showed that the growth cones of two sibling neurons, the G and C cells, follow the same route in the developing grasshopper neuropil until they reach a stereotypic choice point. Here their growth con...Neurons; Axons; Neuropil1983
63 Bastiani, MichaelGuidance of neuronal growth cones: selective fasciculation in the grasshopper embryoOne of the central questions of developmental neurobiology concerns how the diversity and specificity of individual neurons are generated during embryonic development. One major component of neuronal diversity is the complex axonal morphology of individual neurons, largely generated early in develop...Neurons; Filopodia; Axon1983
64 Capecchi, Mario R.Location and function of retroviral and SV40 sequences that enhance biochemical transformation after microinjection of DNA.Biochemical transformation of thymidine-kinase-deficient (TK-) mouse L cells is enhanced 20 to 40 fold when microinjected plasmid DNA contains regions of the genomes of Rous sarcoma virus or simian virus 40 in addition to the complete herpes simplex virus tk gene, irrespective of the orientation and...Animals; Base Sequence; Genes, Viral; Plasmids; Thymidine Kinase1983-07-01
65 Capecchi, Mario R.Measurement of suppressor transfer RNA activity.Transfer RNA (tRNA) suppression of nonsense mutations in prokaryotic systems has been widely used to study the structure and function of different prokaryotic genes. Through genetic engineering techniques, it is now possible to introduce suppressor (Su+) tRNA molecules into mammalian cells. A quanti...Animals; Cells, Cultured; Eukaryotic Cells; Genes, Viral; Mice; Orthomyxoviridae; Peptide Chain Termination, Translational; Protein Biosynthesis1983-08-26
66 Goller, FranzVorkommen und Brut des Bienenfressers (Merops apiaster) in Osttirol (Österreich) (Aves: Meropidae)Synopsis: The first record of Bee-eater for the Eastern Tyrol is imparted by KL1MSCH (1950), three further observations are mentioned. In 1983 a breeding place was discovered near Lavant in about 650 m NN. Feeding adults were watched on the 11th and 12th of August. The breeding place is briefly desc...Merops apiaster; Meropidae; Tyrol1984
67 Coley, Phyllis D.Guía de los arboles comunes del Parque Nacional Soberanía, PanamáEsta es una guía con dibujos para las cincuenta especies de árboles más comunes del bosque tropical en los alrededores del Parque Soberanía, Panamá. También se incluyen siete especies de hierbas y cuatro herbáceas grandes que sobresalen en el sotobosque (bosque bajo). Aunque en el área del p...Arboles; Arbustos1984
68 Olivera, Baldomero M.Poly(ADP-ribosylation) of DNA topoisomerase I: a nuclear response to DNA-strand interruptionsDNA in eukaryotic chromosomes is organized differently from prokaryotic DNA. It seems highly probable that mechanistic adjustments have been made in macromolecular DNA metabolism as a consequence of the chromatin structure of the eukaryotic chromosome (Igo-Kemenes et al. 1982)). This paper deals ...Poly(ADP-ribosylation); Poly(ADP-ribose) synthetase; DNA strand interruption1984
69 Olivera, Baldomero M.Poly(ADP-ribosylation) of DNA topoisomerase I from calf thymusWe demonstrate that the activity of the major DNA topoisomerase I from calf thymus is severely inhibited after modification by purified poly(ADP-ribose) synthetase. Polymeric chains of poly(ADP-ribose) are covalently attached to DNA topoisomerase I. These observations with highly purified enzymes ...ADP-ribosylation; Poly(ADP-ribose) synthetase1984
70 Bastiani, MichaelPathfinding by neuronal growth cones in grasshopper embryo: III. Selective affinity of the G growth cone for the P cells within the A/P fascicleThe growth cone of the G neuron selectively fasciculates upon specific axon bundles in a stereotypic sequence as it navigates through the developing central nervous system of the grasshopper embryo. It turns and extends anteriorly in the contralateral neuropil of the second thoracic ganglion at a s...Axon; Filopodia; Neuropil1984
71 Bastiani, MichaelPathfinding by neuronal growth cones in grasshopper embryos: IV. The effects of ablating the A and P axons upon the behavior of the G growth coneIn the companion paper (Bastiani, M. J., J. A. Raper, and C. S. Goodman (1984) J. Neurosci. 4: 2311-2328), we show that as the G growth cone reaches its choice point and turns anteriorly on the A/P fascicle, its filopodia demonstrate selective affinity for the A/P fascicle as compared to the other a...Labeled pathway; Anterior extension; Fascicle1984
72 Beckerle, Mary C.Microinjected fluorescent polystyrene beads exhibit saltatory motion in tissue culture cellsMicroinjected 0.26-um fluorescent, carboxylated microspheres were found to display classical saltatory motion in tissue culture cells . The movement of a given particle was characterized by a discontinuous velocity distribution and was unaffected by the activity of adjacent particles.Organelles; Microscopy; Proteins1984
73 Davidson, Diane W.Granivory in a desert ecosystem: experimental evidence for indirect facilitation of ants by rodentsTwo major groups of desert granivores, ants and rodents, coexist as permanent residents of local desert habitats in southwestern North America. At our Sonoran Desert study site, both of the major taxa exhibited short-term increase in density when the other taxon was experimentally removed. Over the...Ants; Arizona; Desert annuals; Facilitation; Granivory; Indirect mutualism; Rodents; Seed predation; Sonoran Desert1984
74 Potts, Wayne K.Fall migration of Golden Eagles in the Wellsville Mountains, Northern Utah, 1976-1979Migratory movements of Golden Eagles were investigated in detail as part of a 4-year autumn raptor migration study atop an 8,600-foot ridge in the Wellsville Mountains. In 856 observation hours (161 days) between 6 August and 28 November, 898 Golden Eagles (10% of the oral raptor flight) were counte...Wellsville Mountains; Golden eagles; Fall migration1984
75 Ehleringer, James R.Orientation and slope preference in barrel cactus (Ferocactus acanthodes) at its northern distribution limitMicrosite distribution and diurnal tissue temperature fluctuations were measured in Ferocactus acanthodes (barrel cactus) at its northern distribution limit in the Beaver Dam Mountains of southwestern Utah. At this location, barrel cacti were limited to south-facing slopes. Orientation (azimuth an...Ferocactus acanthodes; Barrel cactus; Slope preference1984
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