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201 Davidson, Diane W.Experimental study of diffuse competition in harvester antsExperiments carried out over a 5-yr period in the Chihuahuan Desert support the a priori prediction of diffuse competition between two species of harvester ants. Despite dietary overlap between a large species {Pogonomyrmex rugosus) and a small species (Pheidole xerophila), the large species facilit...Chihuahuan Desert; Ants; Facilitation; Resource allocation; Granivory1985
202 Goller, FranzExperimental support for a model of birdsong productionIn this work we present an experimental validation of a recently proposed model for the production of birdsongs. We have previously observed that driving the model with simple functions of time, which represent tensions in vocal muscles, produces a wide variety of sounds resembling birdsongs. In th...Vocal; Muscles; Syrinx2003
203 Clayton, Dale H.Experimental test of the importance of preen oil in Rock Doves (Columba livia)Most species of birds have a uropygial gland, also known as a preen gland, which produces oil that birds spread through their plumage when preening. The plumage of waterfowl deprived of uropygial oil becomes brittle and is subject to breakage.Columba livia; Columbiformes; Preen oil; Ectoparasites; Columbicola columbae; Campanulotes compare; Plumage2003
204 Capecchi, Mario R.Expression of a microinjected porcine class I major histocompatibility complex gene in transgenic mice.A porcine class I major histocompatibility complex (SLA) gene has been introduced into the genome of a C57BL/10 mouse. This transgenic mouse expressed SLA antigen on its cell surfaces and transmitted the gene to offspring, in which the gene is also expressed. Skin grafts of such transgenic mice were...Genetic Engineering; Graft Rejection; Mice, Inbred C57BL1985-05-03
205 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
206 Clayton, Dale H.Feather-busting bacteriaI ONCE HAD A COLLEAGUE who delighted in the aphorism, which he proudly coined himself, "If it's too small to see with the naked eye, it ain't there." Sadly, this view may as well be true for ornithologists who study birds only through unaided eyes, binoculars, or spotting scopes. But birds can also ...Columba livia; Columbiformes; Ectoparasites; Bacteria; Plumage1999
207 Moon, Ann M.; Capecchi, Mario R.Fgf8 is required for outgrowth and patterning of the limbs.The expression pattern and activity of fibroblast growth factor-8 (FGF8) in experimental assays indicate that it has important roles in limb development, but early embryonic lethality resulting from mutation of Fgf8 in the germ line of mice has prevented direct assessment of these roles. Here we rep...Animals; Body Patterning; Bone Morphogenetic Proteins; Ectoderm2000-12-26
208 Hughes, Kelly T.Flagellar anti-σ factor FlgM actively dissociates Salmonella typhimurium σ28 RNA polymerase holoenzymeThe anti-σ factor FlgM of Salmonella typhimurium inhibits transcription of class 3 flagellar genes through a direct interaction with the flagellar-specific σ factor, σ28. FlgM is believed to prevent RNA polymerase (RNAP) holoenzyme formation by sequestering free σ28. We have analyzed FlgM-media...sigma-factors; transcription; FlgM; Flagellum1998
209 Hughes, Kelly T.Flagellar-specific transcription factor, σ28, is the Type III secretion chaperone for the flagellar-specific anti-σ28 factor FlgMThe σ28 protein is a member of the bacterial σ70-family of transcription factors that directs RNA polymerase to flagellar late (class 3) promoters. The σ28 protein is regulated in response to flagellar assembly by the anti-σ28 factor FlgM. FlgM inhibits σ28-dependent transcription of genes wh...Flagellum; gene regulation; Type III secretion; FlgM2006
210 Hughes, Kelly T.FliT selectively enhances proteolysis of FlhC Subunit in FlhD4C2 complex by an ATP-dependent protease, ClpXPWe previously reported that the ClpXP ATP-dependent pro-tease specifically recognizes and degrades the flagellar master transcriptional activator complex, FlhD 4C2, to negatively control flagellar biogenesis. The flagellum-related protein, FliT, isalso a negative regulator of flagellar regulon by in...2014-01-01
211 Coley, Phyllis D.; Kursar, Thomas A.Food quality, competition, and parasitism influence feeding preference in a neotropical lepidopteranWe surveyed Lepidoptera found on 11 species of Inga (Fabaceae:Mimosoideae) co-existing on Barro Colorado Island, Panama, to evaluate factors influencing diet choice. Of the 47 species of caterpillars (747 individuals) recorded, each fed on a distinct set of Inga. In the field, 96% of the individuals...Competition; Electivity; Gelechiid; Herbivore growth; Fabaceae; Inga; Leaf expansion; Leafing phenology; Lipidoptera; Panama; Parasitism; Plant quality2006
212 Davidson, Diane W.Foraging ecology and community organization in desert seed-eating antsGranivorous ants in the southwestern deserts of the United States are characterized by species-specific colony foraging behaviors that determine their efficiencies at utilizing seeds from different density distributions. Workers search for food either in groups or as individuals, and these feedin...Ants; Arizona; California; Coexistence; Communities; Density specialization; Desert granivores; Foraging strategies; Insects; New Mexico; Resource partitioning1977
213 Sekercioglu, CaganForest fragmentation hits insectivorous birds hardHabitats around the world, especially in the tropics, are being fragmented at a rapid rate, causing a tremendous loss of biodiversity[1]. For example, 12% of the approximately 10,000 bird species are threatened with extinction in the next 10 to 100 years, and another 8% are near-threatened[2]. This ...2002-01-01
214 Bohs, Lynn A.Four new species of Cyphomandra (Solanaceae) from South AmericaFour new species in the Neotropical genus Cyphomandra are described and illustrated. Cyphomandra pilosa and C. foetida are found on the eastern slopes of the Andes from Colombia to Peru. Cyphomandra oblongifolia is a morphologically variable species of Suriname and the Amazon basin. Cyphomandra sib...Cyphomandra1988
215 Bohs, Lynn A.Four-gene study of evolutionary relationships in Solanum section AcanthophoraThe "spiny solanums," Solanum subgenus Leptostemonum (Solanaceae), comprise a large lineage with over 350 species and include the cultivated eggplant, Solanum melongena. Despite the importance of this subgenus, phylogenetic relationships among these taxa are currently unclear. The present research...Acanthophora; Granule-bound starch synthase gene; GBSSI; ITS; Internal transcribed spacer; Solanum; trnS-trnG; trnT-trnF; Waxy2005
216 Gesteland, Raymond F.; Atkins, John F.Frameshifting in gene 10 of bacteriophage T7Gene 10 of bacteriophage T7, which encodes the most abundant capsid protein, has two products: a major product, 10A (36 kDa), and a minor product, 10B (41 kDa). 10B is produced by frameshifting into the -1 frame near the end of the 10A coding frame and is incorporated into the capsid. The frameshift...Frameshifting; Bacteriophage T7; RNA, Viral; Gene Expression1991
217 Franklin Institute award dinner and ceremony held May 1, 1997This is a 1 hour, 42 minutes, 53 seconds video of the 1997 Franklin Institute Awards Banquet and Ceremony. The awards included a summary of each winner's achievements, the presentation of the award, and an acceptance speech. The award winners included Ralph L. Brinster, the Bower Award and Prize f...Transgenic mice; Gene targeting; Genetic engineering; Molecular genetics; Mutagenesis; Homeobox genes; Histology - Pathological; Gene expression; Gene regulation; Genotype; Phenotype1997
218 Ehleringer, James R.Fuentes de aqua utilizadas por las plantas desérticas y su importancia en planes de manejo y restauración ecológicaEl agua es el factor más importante que afecta a la productividad primaria y la estructura de la vegetación en ecosistemas áridos. Dado que las especies de plantas pueden diferir en sus capacidades de utilizar distintas fuentes de agua, el conocimiento de estos aspectos es fundamental para los ...Fuentes de agua; Isótopos estables; 8-H; 5 l sO; Zonas áridas; Plantas desérticas; Relaciones hídricas; Restauración ecológica; Desierto de Atacama; Atacama Desert; Stable isotopes; Water sources; Arid regions; Ecological restoration; Water relations; Water supplies2000
219 Jorgensen, ErikFunction and misfunction of the two promoters of the Drosophila Antennapedia geneIn the Antennapedia (Antp) gene of Drosophila melanogaster, structurally distinct RNAs arise from different transcription initiation sites. When the two sites are separated by a chromosome inversion, transcripts are produced from each fragment of the split Antp locus, and these RNAs initiate at the ...RNA; Antp; Hybridization1987
220 Carrier, David R.Functional tradeoffs in specialization for fighting versus runningBoth locomotion and fighting are critical to survival and reproductive fitness in many vertebrate species. Yet, characters that make an individual good at fighting may, in many cases, limit locomotor performance and vice versa. Here I describe tests of three functional tradeoffs in the limb muscles ...Greyhounds; Pit Bulls; Australopithecus; Homo; Fighting; Running; Male-male aggression; Limb muscles; Functional tradeoff2002
221 Capecchi, Mario R.Fundamental cellular processes do not require vertebrate-specific sequences within the TATA-binding protein.The 180-amino acid core of the TATA-binding protein (TBPcore) is conserved from Archae bacteria to man. Vertebrate TBPs contain, in addition, a large and highly conserved N-terminal region that is not found in other phyla. We have generated a line of mice in which the tbp allele is replaced with a v...Mice, Knockout; Cells, Cultured; Fibroblasts; Embryo2003-02-21
222 Ehleringer, James R.Gas exchange, δ13C, and heterotrophy for Castilleja linariifolia and Orthocarpus tolmiei, facultative root hemiparasites on Artemisia tridentataGas exchange and carbon isotope ratios were measured on 2 facultative hemiparasites, Castilleja linarifolia Benth. (Indian paintbrush; Scrophulariaceae) and Orthocarpus tolmiei I-I. & A. (Tolmie owl clover; Scrophulariaceae), and their Artemisia tridentata L. (big sagebrush; Asteraceae) hosts. Photo...Heterotrophy; Hemiparasite; Carbon isotope ratios; Shrub ecology; Castilleja linarifolia; Orthocarpus tolmiei; Artemisia tridentata1996
223 Jorgensen, Erik; Carroll, DanaGene activation using FLP recombinase in C. elegansThe FLP enzyme catalyzes recombination between specific target sequences in DNA. Here we use FLP to temporally and spatially control gene expression in the nematode C. elegans. Transcription is blocked by the presence of an "off cassette" between the promoter and the coding region of the desired pro...2008
224 Capecchi, Mario R.Gene targeting. How efficient can you get?With targeting in Leishmania and Trypanosoma, there are now greater incentives to develop the technology in organisms of intermediate complexity such as Caenorhabditis elegans and Drosophila. The ratio of homologous to nonhomologus recombination in these organisms might prove to be greater than in m...Animals; DNA Mutational Analysis; Recombination, Genetic1990-11-08
225 Capecchi, Mario R.Gene targeting: an historical perspectiveOur entry into what was going to become the field of gene targeting began in 1977. I was experimenting with the use of extremely small glass needles to inject DNA directly into the nuclei of living cells. The needles were controlled by hydraulically driven micro-manipulators and were directed into n...Gene targeting -- History; Homologous recombination1998
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