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CreatorTitleDescriptionSubjectDate
401 Ailion, David CharlesDynamics of the pinned modulation wave in incommensurate bis (4-chlorophenyl) sulfone (BCPS)We show that both the anomalously huge resonance-frequency dependence of the 3 5Cl nuclear quadrupole resonance (NQR) spin-lattice relaxation time in BCPS, reported here for the first time, and its anomalous temperature dependence can be explained by large-scale fluctuations of the pinned modulation...NQR; Spin-lattice; Relaxation-time; Pinned modulation wave2002
402 Hultine, KevinEcohydrologic significance of hydraulic redistribution in a semiarid savannaRecent studies have illuminated the process of hydraulic redistribution, defined as the translocation of soil moisture via plant root systems, but the long-term ecohydrologic significance of this process is poorly understood. Copyright [year] American Geophysical Union. Reproduced by permission...Moisture; Roots; Water2008
403 Hultine, KevinEcohydrological implications of woody plant encroachmentIncreases in the abundance or density of woody plants in historically semiarid and arid grassland ecosystems have important ecological, hydrological, and socioeconomic implications. Using a simplified water-balance model, we propose a framework for conceptualizing how woody plant encroachment is li...Carbon cycling; ecohydrology; evapotranspiration2005
404 Ehleringer, James R.; Bush, Sarah Elizabeth; Solomon, Douglas KipEcohydrology in a Colorado River riparian forest: implications for the decline of Populus fremontiiPopulus fremontii (Fremont cottonwood) was once a dominant species in desert riparian forests but has been increasingly replaced by the exotic invasive Tamarix ramosissima (saltcedar). Interspecific competition, reduced flooding frequency, and increased salinity have been implicated in the widespre...Populus fremontii; Decline; Colorado River; Utah; Invasive species; Riparian; Salinity; Sap flow; Tamarix ramosissima; Transpiration2005
405 Clayton, Dale H.Ecoimmunity in Darwin's finches: invasive parasites trigger acquired immunity in the medium ground finch (Geospiza fortis)Invasive parasites pose a serious threat to native animal populations, because hosts with no history of exposure may lack effective immune defenses. Invasive parasites are a particular threat to small, island populations [1,2]. For example, introduced malaria (Plasmodium relictum) has exacerbated t...Darwins finches; Ecoimmunity; Acquired immunity; Medium ground finch; Geospiza fortis; Invasive parasites; Novel parasites; Poxvirus avium; Nest flies; Philornis downsi2010-01-06
406 Clayton, Dale H.Ecological basis of coevolutionary historyMacroevolutionary patterns are difficult to interpret because they are the product of a time scale so vast that deterministic and chance events are hard to distinguish. Although the macroevolutionary history of a group can be reconstructed from extant species, determining the ecological context in ...2003
407 Bowling, David R.Ecological processes dominate the 13C land disequilibrium in a Rocky Mountain subalpine forestFossil fuel combustion has increased atmospheric CO2 by ≈ 115 μmol mol1 since 1750 and decreased its carbon isotope composition (δ13C) by 1.7-2‰(the 13C Suess effect). Because carbon is stored in the terrestrial biosphere for decades and longer, the δ13C of CO2 released by terrestrial ecosyst...2014-01-01
408 Davidson, Diane W.Ecological studies of neotropical ant-gardensIn a census taken in Peru's Manu National Park, 10 epiphytic angiosperms from seven plant families established principally on arboreal carton-ant nests. These "ant gardens" (AGs) were most often inhabited by parabiotic ants, Camponotus femoratus and Crematogaster cf. limata parabiotica, whose polygy...Ant competition; Ant garden; Ant-plant interaction; Coadaptation; Epiphyte; Mutualism; Parabiosis; Preadaptation; Peru; Seed dispersal; Tropical rainforest1988
409 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
410 Ehleringer, James R.Ecosystem physiology responses to global changeMost ecosystems exposed to double ambient C02 show higher peak season net carbon uptake than those growing at current-ambient C02. For grasslands, above-ground biomass increased by an average of 14%, although individual responses for a given system and year range from negative to +85%. The wide ran...Global change ; Ecosystem physiology; Carbon budget; Temperature; Water availability; Nitrogen deposition; Ozone1999
411 Adler, Frederick R.Effect of 1918 PB1-F2 expression on influenza A virus infection kineticsRelatively little is known about the viral factors contributing to the lethality of the 1918 pandemic, although its unparalleled virulence was likely due in part to the newly discovered PB1-F2 protein. This protein, while unnecessary for replication, increases apoptosis in monocytes, alters viral po...2011
412 Adler, Frederick R.Effect of 1918 PB1-F2 expression on influenza A virus infection kineticsAbstract Relatively little is known about the viral factors contributing to the lethality of the 1918 pandemic, although its unparalleled virulence was likely due in part to the newly discovered PB1-F2 protein. This protein, while unnecessary for replication, increases apoptosis in monocytes, alter...2011
413 Gondolo, PaoloEffect of a late decaying scalar on the neutralino relic densityIf the energy density of the Universe before nucleosynthesis is dominated by a scalar field Ø that decays and reheats the plasma to a temperature TRH smaller than the standard neutralino freeze-out temperature, the neutralino relic density differs from its standard value. In this case, the relic de...Neutralinos; Relic density; Reheating temperature2006-10
414 Mattis, Daniel C.Effect of band structure on ferromagnetism*We extend Nagaoka's study of the ferromagnetism of nearly half-filled bands in the infinite-repulsion limit of the Hubbard model by including next-nearest-neighbor tight-binding overlap matrix elements K2. Particles can now get past one another, even in one dimension. We find corroboration of Nagaok...Eigenstates; Spin waves1974-08
415 Vardeny, Zeev ValentineEffect of bias illumination on photoinduced absorption decay in ?-Si:HZeldov and Weiser1 proposed a model to explain the influence of optical biasing on the decay of photoinduced absorption (PA) in ?-Si:H at high temperatures observed by Pfost, Vardeny, and Tauc.2 This model differs from the model originally used2 for interpreting the experimental data at temperatures...Optical biasing; Bias illumination; Photoinduced absorption decay; a-Si:H; Amorphous silicon1985
416 Hughes, Kelly T.The effect of cell growth phase on the regulatory cross-talk between flagellar and Spi1 virulence gene expressionThe flagellar regulon controls Salmonella biofilm formation, virulence gene expression and the production of the major surface antigen present on the cell surface: flagellin. At the top of a flagellar regulatory hierarchy is the master operon, flhDC, which encodes the FlhD4C2 transcriptional complex...2014-01-01
417 Sokolsky, PierreEffect of clouds on apertures of space-based air fluorescence detectorsSpace-based ultra-high-energy cosmic ray detectors observe fluorescence light from extensive air showers produced by these particles in the troposphere. Clouds can scatter and absorb this light and produce systematic errors in energy determination and spectrum normalization. We study the possibilit...Fluorescence; Cloud detection; Extensive air showers2004-01
418 Symko, Orest GeorgeEffect of crystal field on the magnetization of dilute hcp alloysMagnetization measurements on very dilute single-crystal alloys of Mg-Mn, Zn-Mn, and Zn-Cr in the temperature range of 2-0.008 K show that the ground state of these systems is determined by fine-structure splitting. For Mg-Mn the fine-structure constant D is +0.006 K with an effective spin of f whil...HCP alloys; Crystal field; Magnetization; Mg-Mn; Zn-Mn; Zn-Cr1982-04
419 Gondolo, PaoloEffect of dark matter on the first stars: a new phase of stellar evolutionDark matter (DM) in protostellar halos can dramatically alter the current theoretical framework for the formation of the first stars. Heat from supersymmetric DM annihilation can overwhelm any cooling mechanism, consequently impeding the star formation process and possibly leading to a new stellar ...Dark stars2008
420 Miller, Joel Steven; Epstein, Arthur J.Effect of disorder on the linear and nonlinear magnetic susceptibilities of two manganeseporphryin-based magnetsWe analyze the effects of disorder on the magnetic properties of two manganeseporphyrins, [MnTPP][TCNE] •. x(o-DCB) and [MnTPP][TCNE] . • y(o-Xy) and (TPP=meso-tetraphenylporphyrinato, TCNE=tetracyanoethylene, o-Xy=o-xylene, o-DCB=o-dichlorobenzene, x<_3,y<_1). We present data for the in- ...Magnetization; Ferrimagnetic; Spins1997
421 Mishchenko, EugeneEffect of electron-electron interactions on the conductivity of clean grapheneMinimal conductivity of a single undoped graphene layer is known to be of the order of the conductance quantum, independent of the electron velocity. We show that this universality does not survive electron-electron interaction, which results in nontrivial frequency dependence. We begin with analyzi...Optical conductivity; Perturbation theory2007-05
422 Boehme, ChristophEffect of exchange coupling on coherently controlled spin-dependent transition ratesThe effect of exchange interactions within spin pairs on spin-dependent transport and recombination rates through localized states in semiconductors during coherent electron-spin resonant excitation is studied theoretically. It is shown that for identical spin systems, significant quantitative diff...Spin coherence; Electron spin nutations2008-06
423 Mattis, Daniel C.Effect of exciton hopping upon the mass of an excitonA plausible formula derived in a previous paper for the mass Mn* of an exciton in an nth bound state of the electron-hole binding potential is extended so as to include the effect of an exciton-hopping (or Heller-Marcus) mechanism upon Mn*.Frenkel excitons; Exciton-hopping; Heller-Marcus energy; Binding potential1985-10
424 Hultine, Kevin; Bush, Sarah Elizabeth; Ehleringer, James R.Effect of gender on sap-flux-scaled transpiration in a dominant riparian tree species: Box elder (Acer negundo)Acer negundo is a dioecious riparian tree species with a spatial segregation of the sexes along soil moisture gradients. Females are typically more common in wet sites along streams (typically F/M = 1.6), whereas males are more common in drier sites away from streams (typically F/M = 0.6). Spatial s...Density; Ecosystem; Segregation2007
425 Armentrout, Peter B.Effect of kinetic and electronic energy on the reactions of Cr+ with H2, HD, and D2The reactions of atomic chromium ions with H2 , HD, and D2 are examined using guided ion beam tandem mass spectrometry. The ground electronic state (6S) is found to react inefficiently. The thresholds of these data are analyzed to yield a 0 K bond dissociation energy for CrH+ of 1.37 ± 0.09 eV (31...Chromium ions; Hydrogen; Deuteride; Bond energy1987
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