201 - 225 of 631
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CreatorTitleDescriptionSubjectDate
201 Adler, Frederick R.Is space necessary? Interference competition and limits to biodiversityA single trade-off between competitive ability and mortality has been shown to support an arbitrarily large number of species in models of interference competition in spatially structured populations. We show that this results not from spatial structure, but instead from the assumption that a small ...Mortality rate; Competitive ability; Seed size2000
202 Sperry, John S.Analysis of circular bordered pit function I. Angiosperm vessels with homogenous pit membranesA model predicted pit and vessel conductivity, the air-seed pressure for cavitation, and the implosion pressure causing vessel collapse. Predictions were based on measurements from 27 angiosperm species with circular bordered pits and air-seed pressures of 0.2-11.3 MPa. Vessel implosion pressure exc...Functional wood anatomy; hydraulic architecture; plant biomechanics2004
203 Sperry, John S.Evaluation of Murray's law in Psilotum nudum (Psilotaceae), an analogue of ancestral vascular plantsPrevious work has shown that the xylem of seed plants follows Murray's law when conduits do not provide structural support to the plant. Here, compliance with Murray's law was tested in the stem photosynthesizer Psilotum nudum, a seedless vascular plant. Psilotum nudum was chosen because the central...Conduit furcation number; hydraulic architecture; Murray's law2005
204 Bastiani, MichaelCentral projections of the stretch receptor neurons of crayfish: structure, variation, and postembryonic growthEach stretch receptor neuron (SR) of the crayfish abdomen projects from its peripherally located soma an axon that enters the CNS through the second nerve (N2) of its segmental ganglion. CoZ+ backfills of N2 revealed that this axon bifurcates, sending one branch to the brain and the other to the te...Abdomen; Axon; Ganglion1988
205 Seger, Jon; Davidson, Diane W.Biological richness of desertsA desert is "waterless," "treeless," "barren," "remote," "uninteresting," and "presumably uninhabited," according to the authoritative Oxford English Dictionary. The word is derived from deserere, a Latin verb meaning "to leave." In English, to desert is still to "abandon," "forsake," or "fail." Bec...Desert life; Desert biodiversity1995
206 Olivera, Baldomero M.Pyridine nucleotide metabolism in Escherichia coli. IV. TurnoverThere are two pyridine nucleotide turnover pathways in Escherichia coli, the Gholson turnover cycle, with nicotinamide as an intermediate, and a second new pathway which does not involve nicotinamide. In exponentially growing cultures with a generation time of 60 min, the rates of these cycles are ...Turnover cycle; Adenine1973
207 Bastiani, MichaelRole of the cell surface in neuronal pathfindingPerhaps the organ of the human body that evokes the most astonishment, and yet is the least understood, is our brain. From the coordination of simple movements, to consciousness and thought, the function of the nervous system relies on the establishment of trillions of precise connections among the...Axon; molecular guidance code; growth cone1996
208 Bohs, Lynn A.Phylogenetic relationships among the "spiny solanums" (Solanum subgenus Leptostemonum, Solanaceae)Species of Solanum subgenus Leptostemonum comprise almost one third of the genus and are distributed worldwide. Members of this group are defined by their sharp epidermal prickles; thus, they are commonly referred to as the ˜spiny solanums." This subgenus includes a number of economically important...Granule-bound starch synthase gene; GBSSI; Heterandry; ITS; Leptostemonum; Solanum; trnS-trnG; Waxy2006
209 Olivera, Baldomero M.Identification and characterization of a Ca2+-sensitive nonspecific cation channel underlying prolonged repetitive firing in Aplysia neuronsThe afterdischarge of Aplysia bag cell neurons has served as a model system for the study of phosphorylation-mediated changes in neuronal excitability. The nature of the depolarization generating the afterdischarge, however, has remained unclear. We now have found that venom from Conus textile trig...Ca21-activated nonspecific cation channel; Slow inward current; Ion channel modulation; Afterdischarge; Bursting; Aplysia bag cell neurons; Conus textile; Neurotoxins1996
210 Coley, Phyllis D.Patrones en las defensas de las plantas: ? Porque los herbivoros prefrieren ciertas especies?Patterns of heitmory and plant defenses arc presented lor 47 tree species studied on Barro Colorado Island, Panama. Species growing In comparable microhabitats differ in the rates of herbivore damage by 4 orderi of magnitude. Over 70%QT these between-specles differences in herbivory can be explaine...1987
211 Coley, Phyllis D.; Kursar, Thomas A.Effects of weather on fungal abundance and richness among 25 communities in the Intermountain WestBecause moisture and temperature influence the growth of fungi, characterizing weather conditions favorable for fungi may be used to predict the abundance and richness of fungi in habitats with different climate conditions. To estimate habitat favorability to fungi, we examined the relationship of f...Intermountain West; Utah; Microclimate; Fungal prevalence2002
212 Hansen, Mark S.; Healy, Lindsey J.; Johnson, Christopher R.; Capecchi, Mario R.; Keller, Charles; Jones, Greg M.Virtual histology of transgenic mouse embryos for high-throughput phenotyping.A bold new effort to disrupt every gene in the mouse genome necessitates systematic, interdisciplinary approaches to analyzing patterning defects in the mouse embryo. We present a novel, rapid, and inexpensive method for obtaining high-resolution virtual histology for phenotypic assessment of mouse ...Forkhead Transcription Factors; Paired Box Transcription Factors2006
213 Olivera, Baldomero M.; Hillyard, David R.Pyridine nucleotide cycle: studies in Escherichia coli and the human cell line D98/AH2Different metabolic steps comprise the pyridine nucleotide cycles in Escherichia coli and in the human cell line HeLa D98/AH2. An analysis of the "P-labeling patterns in vivo reveals that in E. coli, pyrophosphate bond cleavage of intracellular NAD predominates, while in the human cell line, cleava...Nicotinic acid; Turnover cycle; DNA ligation; Nicotinamide1981
214 Gesteland, Raymond F.; Atkins, John F.; Felden, Brice; McCutcheon, John P.Probing the structure of the Escherichia coli 10Sa RNA (tmRNA)The conformation of the Escherichia coli 10Sa RNA (tmRNA) in solution was investigated using chemical and enzymatic probes. Single- and double-stranded domains were identified by hydrolysis of tmRNA in imidazole buffer and by lead(II)-induced cleavages. Ribonucleases T1 and S1 were used to map unpai...Covariation; Pseudoknot; Structural Probing; 10Sa RNA; tmRNA1997
215 Capecchi, Mario R.Xanthine oxidoreductase is central to the evolution and function of the innate immune system.The housekeeping enzyme xanthine oxidoreductase (XOR) has been studied intensively over the past 100 years, yet the complexity of its in vivo function is still poorly understood. A large body of literature focuses on the different catalyltic forms of XOR and their importance in the synthesis of reac...Animals; Gene Expression Regulation, Enzymologic; Humans; Immune System; Models, Biological2003-09-01
216 Sperry, John S.Anatomy of the palm Rhapis excelsa, VIII. Vessel network and vessel-length distribution in the stemTHE CONCEPT of the vessel, a conducting unit consisting of a series of vessel elements lined up end to end, has been known for well over a century (e.g., Hartig, 1878). The fact that vessels are of limited length is of considerable functional importance. If a vessel is damaged (for example, by an in...Palm stems; Palm stem anatomy; Vessel network; Vessel-length distribution; Primary vascular stem tissue; Hydraulic architechture; Water column1982
217 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
218 Ehleringer, James R.; Rickart, Eric Allan; Dearing, Maria-DeniseStable isotope ratios (?15N AND ?13C) of syntopic shrews (SOREX)Local species richness in shrew (Soricidae) assemblages is often high, and the mechanisms of ecological separation remain relatively unexplored. In this study, hair samples from 6 species of Sorex in 3 separate assemblages were analyzed for stable carbon (13C/12C) and nitrogen (15N/14N) isotope rati...2004
219 Seger, JonIdeas in ecologyThe word "ecology" means different things to different people. For example, during the last 25 years or so the word has been used to label attitudes, life-styles, consumer goods, political parties, and college courses. In the 1960s one university renamed its "Home Economics" course "Home Ecology."...Behavioral ecology; Population ecology1986
220 Capecchi, Mario R.Isolation of a suppressible nonsense mutant in mammalian cellsAn HGPRT- cell line derived from mouse L cells has been shown to have the following properties: it is CRM'; the defective HGPRT molecules are altered in the carboxyterminal peptide; the mutant cells regain HGPRT activity when ochre-suppressor tRNA is microinjected into them, but not when amber...HGPRT cell line; HGPRT activity; Ochre nonsense mutation; Mouse L cells; Mammalian cells1977
221 Capecchi, Mario R.Lessons from angiotensin-converting enzyme-deficient miceSince the first description of renin by Tigerstedt and Bergman [1] in 1898, many papers have described the biochemistry and physiological roles of the reninangiotensin system [2]. A critical component of this system is angiotensin-converting enzyme (ACE), a peptidase which cleaves the inactive pep...1996
222 Capecchi, Mario R.Isolation and characterization of Caenorhabditis elegans DNA sequences homologous to the v-abl oncogene.DNA sequences homologous to the v-abl oncogene were isolated from a Caenorhabditis elegans genomic library by their ability to hybridize with a v-src probe. The DNA sequence of 2465 nucleotides of one clone was determined. This region corresponds to the 5' protein kinase domain of v-abl plus approxi...Amino Acid Sequence; Animals; Base Sequence; Gene Expression Regulation; Transcription, Genetic1986-04
223 Ehleringer, James R.; Bush, Sarah ElizabethEcophysiology of riparian cottonwood and willow before, during, and after two years of soil water removalRiparian cottonwood/willow forest assemblages are highly valued in the southwestern United States for their wildlife habitat, biodiversity, and watershed protection. Yet these forests are under considerable threat from climate change impacts on water resources and land-use activities to support hum...Riparian cottonwood; Riparian willow; Soil water removal; Coyote willow; Drought recovery; Populus fremontii; Riparian ecology; Red Butte Canyon Research Natural Area; Salix exigua; Stem sap flux; Leaf carbon isotope ratios2010
224 Bastiani, MichaelCell-cell interactions during the migration of an identified commissural growth cone in the embryonic grasshopperOne of the fascicles of the posterior commissure of the embryonic grasshopper is pioneered by an individually identifiable neuron named Q1. Q1 initially grows along a longitudinal pathway established by another pioneer neuron, MPl, and then crosses to the midline, where it meets and fasciculates wi...Commissure; Pathfinding; Filopodia1993
225 Gesteland, Raymond F.; Ives, Jeffrey T.; Stockham, Thomas G.Automated film reader for DNA sequencing based on homomorphic deconvolutionAn automated reader for electrophoresis based DNA sequencing methods is described that provides fast and accurate sequence determination. Digitized sequencing lanes are processed with homomorphic blind deconvolution in preparation for peak detection, interlane alignment, peak refinement and base cal...Sequence Analysis; Electrophoresis; Automated Film Reader; Homomorphic Deconvolution1994
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