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CreatorTitleDescriptionSubjectDate
151 Sperry, John S.Shoot dieback during prolonged drought in Ceanothus (Rhamnaceae) chaparral of California: a possible case of hydraulic failureProgressive diebacks of outer canopy branchlets of Ceanothus crassifolius were repeatedly observed after rainless periods up to 9 mo in duration in the Santa Monica Mountains of southern California. Mean xylem pressures of branchlets near the end of drought were as low as -11.2 MPa (N = 22) with a m...Water relations; xylem cavitation; water-stress-induced loss2002
152 Kraus, Peter L.Simon Winchester, Map that changed the worldThe author, noted writer Simon Winchester (who graduated with a Geology degree from Oxford University), makes no secret of the fact that this text is an unabashed tribute to his hero, William Smith, a nineteenth century surveyor and canal digger whose passionate hobby was geology. In the course of S...2002
153 Mcpherson, Brian JamesSimulation of sedimentary rock deformation: lab-scale model calibration and parameterizationUnderstanding the mechanical behavior of rock is critical for researchers and decision-makers in fields from petroleum recovery to hazardous waste disposal. Traditional continuum-based numerical models are hampered by inadequate constitutive relationships governing fracture initiation and growth. To...2002
154 Tiwari, AshutoshSingle crystal TaN thin films on TiN/Si heterostructureWe have successfully grown epitaxial cubic (Bl-NaCl structure) tantalum nitride films on Si (100) and (111) substrate using a pulsed laser deposition technique. A thin layer of titanium nitride was used as a buffer medium. We characterized these films using X-ray diffraction, high resolution transmi...Tantalum nitride; Diffusion barriers; Copper diffusion2002
155 Williams, Clayton C.Single electron tunneling to insulator surfaces detected by electrostatic forceThe detection of single-electron tunneling events between a metallic scanning probe tip and an insulating surface is demonstrated by an electrostatic force method. When a voltage-biased oscillating atomic force microscopy tip is placed within tunneling range of the surface of an insulator, single...Single electron; Tunneling events; Scanning tunneling microscope2002
156 Symko, Orest GeorgeSize considerations in interfacing thermoacoustic coolers with electronicsSmall thermoacoustic coolers heat pumps show much promise for heat management in microcircuits, especially since they can be miniaturized for interfacing with circuits. Usually they are operated in the resonant mode with sound pumping heat; the device dimensions are reduced when the acoustic pump fr...Thermoacoustic coolers; Heat management; Microcircuits; Miniturization2002
157 Chapman, David S.; Harris, Robert N.Snow and the ground temperature record of climate changeBorehole temperature-depth profiles contain a record of surface ground temperature (SGT) changes with time and complement surface air temperature (SAT) analysis to infer climate change over multiple centuries. Ground temperatures are generally warmer than air temperatures due to solar radiation effe...Snow cover; snow modeling; land/atmosphere interactions; borehole climate reconstructions; surface air temperature; ground surface temperature; borehole temperatures; geothermal observations; heat transfer2002
158 Seger, JonSolitary wasps: behavior and natural history by Kevin M. O'NeillMost species of living things are insects, and ter- restrial ecology consists largely of interactions between insects and plants. The biologies of major insect groups such as Hymenoptera should be well documented and well known. Amazingly, they are not. The world is awash in excellent reviews of cur...Insects; Ecological2002
159 Flynn, John J.Standard Oil and Microsoft - intriguing parallels or limping analogies?The computer industry and the law of antitrust have been preoccupied with the struggle between the federal and several state governments and Microsoft for most of the past decade. Microsoft's use of its domination over the personal computer (PC) industry by virtue of its control of the operating sy...2002
160 Liu, FengStep-induced magnetic-hysteresis anisotropy in ferromagnetic thin filmsWe investigate the quasistatic magnetic hysteresis of ferromagnetic thin films grown on a vicinal substrate, using Monte Carlo simulations within a two-dimensional XY model. Intrinsic in-plane anisotropy is assigned to surface sites according to their local symmetry. The simulated hysteresis loops s...Magnetic hysteresis; Ferromagnetic thin films; Step-induced2002
161 Tiwari, AshutoshStress-induced tuning of metal-insulator transition in NdNiO3 filmsWe have used the lattice-mismatch epitaxial strain, induced by the constraint of epitaxy, to tune the metal-insulator (M- I) transition temperature of NdNiO3 films grown on Si(100) substrate. Films were integrated with the Si(100) substrate using several combinations of thin buffer layers. A system...NdNiO3; Silicon substrate; Tantalum nitride; Buffer layers; Biaxial strain2002
162 Olivera, Baldomero M.; Bulaj, GrzegorzStructure of a novel P-superfamily spasmodic conotoxin reveals an inhibitory cystine knot motifConotoxin gm9a, a putative 27-residue polypeptide encoded by Conus gloriamaris, was recently identified as a homologue of the "spasmodic peptide", tx9a, isolated from the venom of the mollusk-hunting cone shell Conus textile (Lirazan, M. B., Hooper, D., Corpuz, G. P., Ramilo, C. A., Bandyopadhyay...Conotoxins; P-superfamily spasmodic conotoxin; Cystine knot motif2002
163 Miller, Jan D.Study of particle-bubble interaction using atomic force microscopy: current possibilities and challengesStudy of interaction forces between mineral particles and air bubbles is a key to understanding flotation processes. Measurement of such interaction forces has only recently been made possible with the introduction of the atomic force microscope (AFM) and the colloidal probe technique. Using AFM, in...Particle-bubble interaction; atomic force microscopy (AFM); hydrophobic force; contact angle; hydrodynamic force2002
164 Adler, Frederick R.Super- and coinfection: filling the rangeHow many different strains of a disease can coexist in a single population of hosts? What effect do different mechanisms of coexistence have on the properties of diseases? The principle of competitive exclusion (Armstrong and McGehee 1980; Levin 1970) states that no more species can coexist in a sys...Superinfection; Virulence; Coexistence2002
165 Myers, Chris J.Synchronous interlocked pipelinesIn a circuit environment that is becoming increasingly sensitive to dynamic power dissipation and noise, and where cycle time available for control decisions continues to decrease, locality principles are becoming paramount in controlling advancement of data through pipelined systems. Achieving fine...2002
166 Tiwari, AshutoshSynthesis and atomic-level characterization of Ni nanoparticles in Al2O3 matrixSingle domain magnetic nickel nanocrystals were embedded in alumina matrix using a pulsed-laser deposition technique. Structural characterization carried out at the atomic level using scanning transmission electron microscopy with atomic number contrast (STEM-Z) in conjunction with electron energy ...Nanophase magnetic materials; Alumina2002
167 Bastiani, Michael; Bandyopadhyay, Pradip K.; Olivera, Baldomero M.; Golic, Kent G.Targeted mutagenesis by homologous recombination in D. melanogasterWe used a recently developed method to produce mutant alleles of five endogenous Drosophila genes, including the homolog of the p53 tumor suppressor. Transgenic expression of the FLP site-specific recombinase and the I-SceI endonuclease generates extrachromosomal linear DNA molecules in vivo.Mutations; Drosophila; Gene targeting2002
168 Olivera, Baldomero M.Targeted mutagenesis by homologous recombination in D. melanogasterWe used a recently developed method to produce mutant alleles of five endogenous Drosophila genes, including the homolog of the p53 tumor suppressor. Transgenic expression of the FLP site-specific recombinase and the I-SceI endonuclease generates extrachromosomal linear DNA molecules in vivo. Thes...2002
169 Wight, Charles AlbertThermal activation of the high explosive NTO: sublimation, decomposition, and autocatalysisThermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) show that the heating of 5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one (NTO) leads to competitive sublimation and condensed-phase exothermic decomposition. Model-free isoconversional analysis has determined activation energies...NTO; Thermal activation; Differential scanning calorimetry; Exothermic decomposition; Competitive sublimation2002
170 Wight, Charles AlbertThermal decomposition of a melt-castable high explosive: isoconversional analysis of TNAZThe thermal decomposition kinetics of the high explosive 1,3,3-trinitroazetidine (TNAZ) have been measured by nonisothermal differential scanning calorimetry (DSC). Samples of TNAZ in open pans and pierced pans undergo mainly melting (?Hfus = 27 ± 3 kJ mol-1) and vaporization (?Hvap = 74 ± 10 kJ m...Thermal decomposition; Melt-castable high explosive; TNAZ; Nonisothermal differential scanning calorimetry; Exothermic decomposition2002
171 Armentrout, Peter B.Thermochemistry of small cationic iron-sulfur clustersThe kinetic energy dependences of the reactions of Fen 1 with COS (n=2-6) and CS2 (n=2-5) are studied in a guided-ion beam tandem mass-spectrometer. The main products arise from sulfur transfer and subsequent losses of Fe atoms. In the case of CS2 , this reactant also formally replaces one Fe atom ...Iron-sulfur clusters; Endothermic reactions; Bond energy2002
172 Bernstein, Paul S.Transformations of selected carotenoids in plasma, liver, and ocular tissues of humans and in nonprimate animal modelsPURPOSE: To determine the stereochemistry of carotenoids in human ocular tissues in comparison with plasma and liver and to elucidate the possible transformations of dietary (3R,3'R,6'R)-lutein and (3R,3'R)-zeaxanthin in the eye. Similarly, to characterize the carotenoid profiles in the eye tissues,...Chromatography, High Pressure Liquid; Stereoisomerism; Xanthophylls2002
173 Kriesel, John D.; Spruance, Spotswood L.Treatment of herpes simplex labialis.Recurrent herpes simplex labialis is associated with mild morbidity, but remains a significant problem for people with frequent and/or severe recurrences. Both topical and peroral episodic antiviral treatments of recurrences are modestly effective at reducing the duration of signs and symptoms. Rece...Randomized Controlled Trials; Steroids; Drug Administration Routes2002
174 Coley, Phyllis D.Tritrophic interactions in tropical versus temperate communitiesThe latitudinal gradient in diversity is one of the oldest (e.g., Wallace, 1878) and most obvious trends in ecology, and a wealth of literature is devoted to understanding both the causes and consequences of this gradient (Dobzhansky, 1950; also reviewed by Rohde, 1992). Given the enormous latitudi...Tritrophic interactions; Trophic cascades; Herbivory; Tropical communities; Temperate communities2002
175 Couldwell, William T.Tunneled lumbar drainThe authors report a simple and rapid procedure for tunneling a lumbar drain subcutaneously to facilitate chronic cerebrospinal fluid (CSF) drainage. A standard lumbar puncture (LP) is performed with a large-bore Tuohy needle (14- to 16-gauge), the drainage catheter is advanced into the subarachnoid...Lumbar drain; Fistula2002
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