201 - 225 of 1,938
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CreatorTitleDescriptionSubjectDate
201 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Linear and nonlinear photoexcitation dynamics in ∏-conjugated polymersLinear and nonlinear recombination kinetics with various lifetime distributions were identified for long-lived photoexcitations in a series of rr-conjugated polymer films using modulation frequency and excitation intensity dependencies of the photoinduced absorption. This includes monomolecular, bim...Linear photoexcitation; Nonlinear photoexcitation; pi-conjugated polymers; Recombination kinetics2003-01
202 Ehleringer, James R.ENSO effects on primary productivity in Southern Atacama desertIn the winter-rain southern Atacama Desert of the Coquimbo Region of Chile, El Niño - Southern Oscillation (ENSO) events modulate primary productivity. In this region, there are important changes in water availability between La Niña (dry) and El Niño (rainy) years. Using interannual comparison...El Niño; Atacama Desert; Terrestrial ecosystems; Plant productivity2006
203 Farmer, Colleen G.Right-to-left shunt of crocodilians serves digestionAll amniotes except birds and mammals have the ability to shunt blood past the lungs, hut the physiological function of this ability is poorly understood. We studied the role of the shunt in digestion in juvenile American alligators in the following ways. First, we characterized the shunt in fasting...Postprandial; Alligators; Gastrointestinal2008
204 DeTar, CarletonPotts flux tube model at nonzero chemical potentialWe model the deconfinement phase transition in quantum chromodynamics at nonzero baryon number density and large quark mass by extending the flux tube model ~three-state, three-dimensional Potts model! to nonzero chemical potential. In a direct numerical simulation we confirm mean-field-theory pre...Phase transitions; Quark-gluon plasma; Chemical potential; Potts model2000-03
205 Vardeny, Zeev ValentinePolarization memory decay spectroscopy of photoexcitations in ∏-conjugated polymers: evidence for excimersWe used the technique of ultrafast transient polarized photomodulation in the visible/near-infrared range and polarization memory decay (PMD) spectroscopy to study the primary photoexcitations in films and solutions of two poly(phenylene-vinylene) (PPV) derivatives, namely, 2-methoxy-5-(2'-ethylhex...Photoexcitations; pi-conjugated polymers; Polarization memory decay spectroscopy; PMD; DOO-PPV; MEH-PPV; Ultrafast transient polarized photomodulation; Intrachain singlet excitons; Excimers; Interchain charge transfer exciton2008-05
206 Gondolo, PaoloImproved constraints on supersymmetric dark matter from muon g-2The new measurement of the anomalous magnetic moment of the muon by the Brookhaven AGS experiment 821 again shows a discrepancy with the standard model value. We investigate the consequences of these new data for neutralino dark matter, updating and extending our previous work [E. A. Baltz and P. ...Magnetic moment; Neutralinos2003-03
207 Carrier, David R.Evidence for endothermic ancestors of crocodiles at the stem of archosaur evolutionPhysiological, anatomical, and developmental features of the crocodilian heart support the paleontological evidence that the ancestors of living crocodilians were active and endothermic, but the lineage reverted to ectothermy when it invaded the aquatic, ambush predator niche. In endotherms, there i...Endothermy; ectothermy; Archosaur evolution; Archosaurs; Crocodilian heart2004
208 Wu, Yong-ShiOpen spin chain and open spinning stringIn this letter, we study the open spinning strings and their SYM duals. A new class of folded open spinning strings is found. At planar one-loop level in SYM, by solving the thermodynamic limit of the Bethe ansatz equations for an integrable open spin chain, we find good agreement with string theory...2004-07
209 Crespo, Jose GuillermoOlfactory modulation of pre-flight shivering behavior in male mothsIn nocturnal moths olfaction is the predominant sensory modality shaping many of the adult animal?s activities, including reproduction. A two-component pheromone blend is sufficient to elicit the typical zigzag upwind flight behavior in Helicoverpa zea males. However, before flight can be initiated,...thermoregulation, warm-up, flight, sex pheromone, Noctuidae, insect Department: Biology2011-01-02
210 Goller, FranzMotor control of crystallized song is modified by sensory feedbackSong production requires precisely coordinated activity in the respiratory and syringcal (vocal organ) muscles. Crystallized adult song is characterized by acoustic and motor stereotypy which does not require auditory feedback, suggesting it is represented by fixed central motor programs. To determ...Air injection; Auditory feedback; Pressure1997
211 Kieda, David B.; Bergman, Douglas R.; Sokolsky, PierreMeasurement of the flux of ultrahigh energy cosmic rays from monocular observations by the high resolution fly's eye experimentWe have measured the cosmic ray spectrum above 10^172 eV using the two air-fluorescence detectors of the High Resolution Fly's Eye observatory operating in monocular mode.We describe the detector, phototube, and atmospheric calibrations, as well as the analysis techniques for the two detectors.We ...High Resolution Fly's Eye; Ultrahigh energy cosmic rays2004-04
212 Wu, Yong-ShiAlgebraic and geometric aspects of generalized quantum dynamicsWe briefly discuss some algebraic and geometric aspects of the generalized Poisson bracket and noncommutative phase space for generalized quantum dynamics, which are analogous to properties of the classical Poisson bracket and ordinary symplectic structure.Quantum dynamics; Jacobi identity1994-06
213 Golden, Kenneth M.Critical behavior of transport in lattice and continuum percolation modelsIt has been observed that the critical exponents of transport in the continuum, such as in the Swiss cheese and random checkerboard models, can exhibit nonuniversal behavior, with values different than the lattice case. Nevertheless, it is shown here that the transport exponents for both lattice a...Ising model; Magnetization; Scaling1997
214 Olivera, Baldomero M.Uniquely selective inhibitor of the mammalian fetal neuromuscular nicotinic acetylcholine receptorWe have purified and characterized a novel conotoxin from the venom of Conus obscurus, which has the unique property of selectively and potently inhibiting the fetal form of the mammalian neuromuscular nicotinic acetylcholine receptor (nAChR) (α1β1γδ-subunits). Although this conotoxin, αA-cono...Conotoxins; Conus obscurus; Fetal; Muscle; nAChR; Inhibitor; Receptor2005-01-19
215 Gesteland, Raymond F.Processing of adenovirus 2-induced proteinsAnalysis of (35)S-methionine-labeled extracts of adenovirus 2-infected KB cells revealed 22 virus-induced polypeptide components. Most proteins of the virion were easily detected in extracts of whole cells labeled for short periods between 15 and 30 h after infection; however, several virion compone...Adenoviridae; Viral Proteins; Protein Precursors; Methionine; Mouth Neoplasms1973
216 Bohs, Lynn A.Phylogeny of the Cyphomandra clade of the genus Solanum (Solanaceae) based on ITS sequence data13 major clades can be recognized within the genus Solatium (Solanaceae) based on chloroplast DNA sequence data. One of these is the Cyphomandra clade, which includes about 50 neotropical species. These have traditionally been placed into two or three sections: S. section Pachyphylla (formerly recog...Cyphomandra; ITS; osmophores; self-incompatibility; Solanum2007
217 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
218 Boehme, ChristophElectrical detection of spin coherence in siliconExperimental evidence is presented showing that photocurrents in silicon can be used as highly sensitive readout probes for coherent spin states of localized electrons, the prime candidates for quantum bits in various semiconductor based quantum computer concepts. Conduction electrons are subjected ...Spin coherence; Electronic transitions; Rabi oscillation2003-12
219 Olivera, Baldomero M.; McIntosh, J. Michael; Hillyard, David R.A-superfamily of conotoxins: structural and functional divergenceThe generation of functional novelty in proteins encoded by a gene superfamily is seldom well documented. In this report, we define the A-conotoxin superfamily, which is widely expressed in venoms of the predatory cone snails (Conus), and show how gene products that diverge considerably in stru...Conotoxins; A-superfamily conotoxin2004-02-03
220 Shapiro, Michael D.Adaptive evolution of pelvic reduction in sticklebacks by recurrent deletion of a Pitx1 enhancerThe molecular mechanisms underlying major phenotypic changes that have evolved repeatedly in nature are generally unknown. Pelvic loss in different natural populations of threespine stickleback fish has occurred by regulatory mutations deleting a tissue-specific enhancer of the Pituitary homeobox t...Adaptive evolution; Pelvic reduction; Pituitary homeobox transcription factor 1; Pitx1; Gasterosteus aculeatus2010-01-14
221 Mishchenko, EugeneOptical conductivity of a two-dimensional electron liquid with spin-orbit interactionThe interplay of electron-electron interactions and spin-orbit coupling leads to a new contribution to the homogeneous optical conductivity of the electron liquid. The latter is known to be insensitive to many-body effects for a conventional electron system with parabolic dispersion. The parabolic...Optical conductivity; Electron liquid; Spin-orbit coupling2006-08
222 Miller, Joel StevenPhotoelectron spectra of transition-metal carbonyl complexes: comparison with the spectra of adsorbed COThe uv and x-ray photoelectron spectra of carbon monoxide and transition-metal (TM) carbonyl complexes have been studied. The systematic changes in these spectra were recorded as the number of metal atoms in the complexes was increased and as the bonding configuration of the CO changed. The observat...TM carbonyl complexes; electron binding energies; metal atoms1978
223 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
224 Vardeny, Zeev ValentinePicosecond optical time-of-flight studies of carrier transport in α-Si:H/α-SiNx:H multilayersWe report time-of-flight experiments in the time range from 0.2 psec to 1.8 nsec in 0-Si:H-a-SiNx:H multilayer structures using a purely optical technique. The transport mechanism of photoexcited carriers is shown to be dispersive and its characteristic parameters are determined in the temperature r...Time-of-flight; Amorphous silicon; Carrier transport; Photoexcited carriers1987-09
225 Capecchi, Mario R.Hox group 3 paralogous genes act synergistically in the formation of somitic and neural crest-derived structures.Hox genes encode transcription factors that are used to regionalize the mammalian embryo. Analysis of mice carrying targeted mutations in individual and multiple Hox genes is beginning to reveal a complex network of interactions among these closely related genes which is responsible for directing th...Abnormalities, Multiple; Gene Targeting; Glossopharyngeal Nerve; Mice, Knockout; Morphogenesis1997-12-15
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