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CreatorTitleDescriptionSubjectDate
176 Ehleringer, James R.Carbon isotope discrimination in the C4 shrub Atriplex confertifolia along a salinity gradientCarbon isotope discrimination (∆) was measured for leaves of Atriplex confertifolia along a salinity gradi~ ent in northern Utah. Over this gradient, the variation of ∆ values was high for a C4 species, and the ∆ values were positively correlated with salinity in both years of the study. Of th...Carbon isotope ratio; Salt stress; Bundle sheath leakiness; Halophyte; Atriplex confertifolia; Salinity gradient1995
177 Ehleringer, James R.Carbon isotope dynamics in Abies amabilis stands in the CascadesCarbon isotope ratios (d13C) of canopy air and carbon isotope discrimination at the ecosystem level were studied in three montane Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Dougl. ex J. Forbes) stands, an old-growth and two younger stands. Spatial and temporal variations of canopy CO2 con...Carbon isotopes; Pacific silver fir; Carbon budget; Soil respiration; Cascade Mountains1998
178 Ehleringer, James R.Carbon isotope ratios in belowground carbon cycle processesAnalyses of carbon isotope ratios (δ13C) in soil organic matter (SOM) and soil respired CO2 provide insights into dynamics of the carbon cycle. δ13C analyses do not provide direct measures of soil CO2 efflux rates but are useful as a constraint in carbon cycle models. In many cases, δ13C analyses...Below ground processes; Ecosystems; Carbon cycle; Carbon isotope ratio; Ecosystem processes; Global change; Soil organic carbon; Soil organic matter2000
179 Ehleringer, James R.Carbon isotope ratios of Atacama Desert plants reflect hyperaridity of region in northern ChileLeaf carbon isotope ratios were measured on plants from the coastal portions of the Atacama Desert at Pan de Azucar and Paposo, Chile. Most species possessed C3 photosynthesis, although there were several CAM species, indications of some facultative CAM species, and only one C4 species. The carbon i...Atacama Desert; Carbon isotope ratio; Intercellular carbon dioxide concentration; Hyperaridity1998
180 Carter, Tony M.Cascade: hardware for high/variable precision arithmeticThe Cascade hardware architecture for high/variable precision arithmetic is described. It uses a radix-16 redundant signed-digit number representation and directly supports single or multiple precision addition, subtraction, multiplication, division, extraction of the square root and computation...1989
181 Poulter, Charles DaleCatalytic mechanism of Escherichia coli isopentenyl diphosphate isomerase involves Cys-67, Glu-116, and Tyr-104 as suggested by crystal structures of complexes with transition state analogues and irreversible inhibitorsIsopentenyl diphosphate (IPP):dimethylallyl diphosphate (DMAPP) isomerase is a key enzyme in the biosynthesis of isoprenoids. The reaction involves protonation and deprotonation of the isoprenoid unit and proceeds through a carbocationic transition state. Analysis of the crystal structures (2 A) of ...Catalytic Domain; Crystallography; Organophosphorus Compounds2003-04-04
182 Sekercioglu, CaganCauses and consequences of bird extinctionsIncreased human domination of the planet has caused the declines and extinctions of countless species. Each species has not only intrinsic value, but ecological functions of organisms are also essential for the integrity of ecosystems that allow people to benefit from essential free ecosystem servic...2003-01-01
183 Torti, Sylvia D.; Coley, Phyllis D.; Kursar, Thomas A.Causes and consequences of monodominance in tropical lowland forestsTropical canopy dominance in lowland, well-drained forests by one plant species is a long-standing conundrum in tropical biology. Research now shows that dominance is not the result of one trait or mechanism. We suggest that the striking dominance of Gilbertiodendron dewevrei in the Ituri Forest of ...Monodominance; Gilbertiodendron dewevrei; Ituri Forest; Understory2001
184 Sperry, John S.Cavitation fatigue - the weakening of cavitation resistance of xylem and its reversibilityXylem function is essential for the growth and survival of higher land plants. Xylem must not only be efficient under favorable conditions to facilitate high rates of stomatal conductance and carbon uptake, but it should also remain functional under drought conditions, when water potential (Ψ) dro...Cavitation fatigue; Drought; Pit membrane2003
185 Dawson, KyleCCD testing and characterization for dark energy surveyA description of the plans and infrastructure developed for CCD testing and characterization for the DES focal plane detectors is presented. Examples of the results obtained are shown and discussed in the context of the device requirements for the survey instrument.DES2006
186 Davidson, Diane W.Cecropia and its biotic defensesIn all the world, the genus Cecropia is unrivaled for the number of myrmecophytes, or true "antplants" counted among its species (McKey & Davidson, 1993). Based on the proportion of Cecropia species producing Mullerian bodies in at least some parts of their distribution, myrmecophytes comprise the ...Myrmecophytes; Mullerian bodies; Pearl bodies2005
187 Carter, Tony M.; Smith, Kent F.Cell matrix methodologies for integrated circuit designA class of integrated circuit design and implementation methodologies is described. These techniques are unique in that they simultaneously model both function and interconnect using cells. These cells are designed such that cell adjacency normally implies interconnection. The absence of an interco...Integrated circuit design; Cell matrix1989
188 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
189 Gesteland, Raymond F.Cell-free synthesis of herpes simplex virus proteinsPolyribosomes isolated from herpes simplex virus type I (HSV-1)-infected cells have been used to program a eucaryotic cell-free translation system. At least 10 HSV-specific polypeptides, with apparent molecular weights of 25,000 to 160,000, are synthesized by wild-type HSV-infected polyribosomes. Po...Viral Proteins; Herpes Simplex; Peptide Biosynthesis; Thymidine Kinase1977
190 Bastiani, MichaelCentral projections of the stretch receptor neurons of crayfish: segmental gradients of synaptic probability and strengthThe 20 stretch receptor neurons (SRs) of the crayfish abdomen send axons into the CNS that then project both to the brain and to the last abdominal ganglion, G6 (Bastiani and Mulloney, 1988). In G6, we recorded intracellularly from different kinds of neurons postsynaptic to SR axons.Axons; Synapses; SR1988
191 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
192 Symko, Orest GeorgeChaos in long Josephson junctions without external rf driving forceSimulations of long Josephson junctions in an external magnetic field show a variety of chaotic behaviors. They consist of period-doubling bifurcation, intermittency between and within Fiske steps, and quasiperiodic motion at Fiske steps. A physical explanation for the chaotic behavior is presented....Fiske steps; Chaos; Chaotic behaviors1990-09
193 Symko, Orest GeorgeCharacteristics of YBaCuO magnetic shieldsMagnetic shielding properties of YBaCuO tubes have been studied at temperatures of 77 K and 4 K. Shielding effectiveness was determined by measuring the magnetic field inside the tube in the presence of external magnetic fields. A high degree of shielding was achieved up to a critical external fie...YBaCuO magnetic shields; SQUID1991-03
194 Gesteland, Raymond F.Characterization of lysozyme messenger and lysozyme synthesized in vitroIn vitro systems for protein systhesis have been in wide use for about 10 years. In most of the early work protein synthesis was measured by following the incorporation of radioactive amino acids into acid precipitable material. This test cannot distinguish between the synthesis of complete, activ...Lysozyme Messenger; Lysozyme Synthesized; Protein Synthesis1969
195 Miller, Joel StevenCharacterization of novel TCNQ and TCNE 1 : 1 and 1 : 2 salts of the tetrakis(dimethyamino) ethylene dication, [{(CH3)2N}2C-C{N(CH3)2}2]2+Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C-C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9(o), while the TCNQ anions crystallize as [TCNQ]2 2- dimers with an interplanar separation of 3.1...Electron; Oxidations; Transfer1996
196 Wu, Yong-ShiCharacterization of one-dimensional Luttinger liquids in terms of fractional exclusion statisticsWe develop a bosonization approach to study the low temperature properties of one-dimensional gas of particles obeying fractional exclusion statistics (FES). It is shown that such ideal gas reproduces the low-energy excitations and asymptotic exponents of a one-component Luttinger liquid (with no in...2001-06
197 Beckerle, Mary C.Characterization of the interaction between zyxin and members of the Ena/Vasodilator-stimulated Phosphoprotein family of proteinsZyxin contains a proline-rich N-terminal domain that is similar to the C-terminal domain in the ActA protein of the bacteria, Listeria monocytogenes. We screened the entire amino acid sequence of human zyxin for Menainteracting peptides and found that, as with ActA, proline-rich sequences were the s...Zyxin; Actin; Listeria monocytogenes; Proline-rich repeats; Cell spreading2000
198 Capecchi, Mario R.Characterization of three proteins involved in polypeptide chain termination.At each stage of elongation, the growing polypeptide chain is bound to the ribosome-messenger RNA complex through the transfer RNA of the most recently incorporated amino acid residue. When the chain is complete, the last polypeptide-transfer RNA (tuna) ester linkage is cleaved, releasing the chain ...Anti-Bacterial Agents; Phenylalanine; Stimulation, Chemical1969
199 Stringfellow, Gerald B.;Inglefield, Colin E.;Taylor, P. CraigCharacterization of unicompositional GaInP2 ordering heterostructures grown by variation of V/III ratioPhotoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies are employed to investigate single heterostructures based on two GaInP2 layers that have the same composition but different degrees of order on the cation sublattice. Four sample configurations are studied: two complemen...Heterostructures; Growth parameters; Growth temperature1997
200 Minteer, Shelley D.Characterizing efficiency of multi-Enzyme cascade-based biofuel cells by product analysisThe performance of biofuel cells with enzyme cascades have normally been characterized with open circuit potential, power density, and current density measurements. In this work, we demonstrate that with the method of quantitative product analysis by mass spectrometry, we can obtain other valuable i...2014-01-01
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