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51 Adler, Frederick R.Aggregation and stability in parasite-host modelsThis paper generalizes the two-dimensional approximation of models of macroparasites on homogeneous populations developed by Anderson & May (1978), focusing on how the dispersion (the variance to mean ratio) of the equilibrium distribution of parasites on hosts is related to the stability of the equ...Aggregation; Stability; Host-parasite models1992-04
52 Lupton, John MarkAir-induced fluorescence bursts from single semiconductor nanocrystalsWe observe a dramatic enhancement of the fluorescence intensity from single core/shell CdSe/ZnS nanocrystals upon sudden exposure to air from an evacuated surrounding. Both the number of particles contributing to emission increases as well as the average emission intensity from a single particle, le...CdSe; ZnS; Air-induced; Fluorescence bursts2004
53 Albert Lasker Awards Ceremony, 2001This is the 1 hour, 45 minutes, and 41 seconds video of the Lasker Awards Ceremony and Banquet held in September, 2001. The Albert Lasker Award for Basic Medical Research was given to Mario R. Capecchi, Oliver Smithies, and Martin Evans for their work in genetic research. Martin Evans discovered h...Capecchi, Mario R.; Gene targeting; Embryonic stem cells; Transgenic mice; Genetic engineering; Science - Awards - United States; Smithies, Oliver; Evans, Martin J.; Awards presentations2001
54 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
55 Wu, Yong-ShiAlgebraic solution for a two-level atom in radiation fields and the Freeman resonancesUsing techniques of complex analysis in an algebraic approach, we solve the wave equation for a two-level atom interacting with a monochromatic light field exactly. A closed-form expression for the quasienergies is obtained, which shows that the Bloch-Siegert shift is always finite, regardless of ...Bloch-Siegert shift; Freeman resonances; Quasienergies2006-02
56 Armentrout, Peter B.Alkali metal cation interactions with 12-crown-4 in the gas phase: revisitedQuantitative interactions of alkali metal cations with the cyclic 12-crown-4 polyether ligand (12C4) are studied. Experimentally, Rb+(12C4) and Cs+(12C4) complexes are formed using electrospray ionization and their bond dissociation energies (BDEs) determined using threshold collision-induced dissoc...2012-01-01
57 Coley, Phyllis D.; Lokvam, John; Kursar, Thomas A.Allelochemic function for a primary metabolite: the case of L-tyrosine hyper-production in Inga umbellifera (Fabaceae)Young leaves of tropical forest trees experience far higher herbivory pressure than mature leaves of the same species. Selection on young leaves has led to diverse forms of defense chemical expression. Though most allelochemicals are secondary metabolites, allelochemic function for a primary metabol...5-amino-4-hydroxy-pentanoic acid; Panama; Barro Colorado Island; Fabaceae; Inga umbellifera; Primary metabolite; Heliothis virescens2006
58 Capecchi, Mario R.Altered enzymes in drug-resistant variants of mammalian tissue culture cells.Two selective procedures are compared in an effort to isolate variants of mouse L cells containing structural gene mutations. Among the resulting variant cloned cell lines are found two types of alterations in theenzyme hypoxanthine phosphoribosyl transferase (EC (1): enzyme with altered ...Drug Resistance; Azaguanine; Clone Cells; Hypoxanthines1973-11
59 Adler, Frederick R.Alternating host cell tropism shapes the persistence, evolution and coexistence of Epstein-Barr virus infections in humanEpstein-Barr virus (EBV) infects and can persist in a majority of people worldwide. Within an infected host, EBV targets two major cell types, B cells and epithelial cells, and viruses emerging from one cell type preferentially infect the other. We use mathematical models to understand why EBV infec...2011
60 Adler, Frederick R.Alternating host cell tropism shapes the persistence, evolution and coexistence of Epstein-Barr virus infections in humanEpstein-Barr virus (EBV) infects and can persist in a majority of people worldwide. Within an infected host, EBV targets two major cell types, B cells and epithelial cells, and viruses emerging from one cell type preferentially infect the other. We use mathematical models to understand why EBV infec...2010
61 Olivera, Baldomero M.Alternative splicing in the pore-forming region of shaker potassium channelsWe have cloned cDNAs for the shaker potassium channel gene from the spiny lobster Panulirus interruptus. As previously found in Drosophila, there is alternative splicing at the 59 and 39 ends of the coding region. However, in Panulirus shaker, alternative splicing also occurs within the pore-forming...Panulirus interruptus; Conotoxins; Shaker; Stomatogastric ganglion; Pore-forming region; Alternative splicing1997
62 Coffin, Cheryl M.; Capecchi, Mario R.Alveolar rhabdomyosarcomas in conditional Pax3:Fkhr mice: cooperativity of Ink4a/ARF and Trp53 loss of function.Alveolar rhabdomyosarcoma is an aggressive childhood muscle cancer for which outcomes are poor when the disease is advanced. Although well-developed mouse models exist for embryonal and pleomorphic rhabdomyosarcomas, neither a spontaneous nor a transgenic mouse model of alveolar rhabdomyosarcoma has...Cell Differentiation; Forkhead Transcription Factors; Myogenic Regulatory Factors2004-11-01
63 Mattis, Daniel C.; Sutherland, BillAmbiguities with the relativistic δ-function potentialIn many cases of physical interest, the 6-function potential is a very convenient approximation to more structured, and more difficult, short-ranged potentials. In relativistic theories, its use is often mandated because only a mathematical point has a relativistically invariant shape. Neverthele...Delta function; Energy states1981-09
64 Olivera, Baldomero M.Aminoglycoside effects on voltage-sensitive calcium channels and neurotoxicityTo the Editor: Since ototoxicity and neuromuscular toxicity of aminoglycoside antibiotics are reversed by calcium, 1,2 and presynaptic events appear to be involved in aminoglycoside-induced neuromuscular blockade, 3,4 we suspected a role for voltage-sensitive calcium channels in aminoglycoside neuro...Conotoxins1987
65 Vardeny, Zeev Valentine; Gellermann, WernerAmplified resonant Raman scattering in conducting polymer thin filmsUsing picosecond pulsed laser excitation, we investigate the optical emission characteristics of poly(2,5-dioctyloxy-p-phenylenevinylene), (DOO-PPV), thin films at high excitation intensities (~1-90 MW/cm2). We observe the presence of amplified resonance Raman scattering in the emission spectra of c...Amplified resonant Raman scattering; High excitation intensities; pi-conjugated polymers1998
66 Vardeny, Zeev ValentineAmplified spontaneous emission and lasing in conducting polymers and fluorescent dyes in opals as photonic crystalsSpectral narrowing of photoluminescence (PL) and evolution of sharp emission lines upon optical excitation have been observed in opals made of SiO2 spheres infiltrated with conducting polymers such as OOPPV and MDDOPPV and also fluorescent dyes such as rhodamine 6G, NK-3483, and coumarin 120. Their ...Amplified spontaneous emission; Lasing; Fluorescent dyes1999
67 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Amplitude and phase modes in trans-polyacetylene: resonant Raman scattering and induced infrared activityThe resonant Raman scattering (RRS) from the three Ag modes of trans-polyacetylene and the charged-induced ir modes are analyzed with use of the amplitude- and phase-mode theories. It is shown that the observed phonon frequencies and the relative intensities of all modes obtained at various laser ex...Induced infrared activity; Ag modes; Amplitude modes; Phase modes; Trans-polyacetylene1987-07
68 Sokolsky, PierreAn analog light scattering experiment of hexagonal icelike particles. part I: experimental apparatus and test measurementsAn experimental apparatus to measure the scattering properties of hexagonal icelike particles in the analog manner at the helium neon laser wavelength of 0.633 mm has been designed and built. The instrument consists of an array of 36 highly sensitive and linear photodiode detectors that are positi...1999
69 Sokolsky, PierreAn analog light scattering experiment of hexagonal icelike particles. part II: experimental and theoretical resultsThe scattering properties of hexagonal icelike crystals as measured in the analog manner by the experimental apparatus described in Part I are presented. The crystals are made out of sodium fluoride (NaF), which has an index of refraction similar to that of water ice. The experimentally determined...1999
70 Mattis, Daniel C.An expanded Luttinger modelThis paper generalizes Luttinger's model by introducing curvature (d2ε (k) dk2 ≠ 0 ) into the kinetic energy. An exact solution for arbitrary interactions is still possible in principle, but it now requires disentangling the eigenvalue spectrum of an harmonic string of interacting boson fields at...2012-01-01
71 Clayton, Dale H.An experimental test of the effects of behavioral and immunological defenses against vectors: do they interact to protect birds from blood parasites?Background: Blood-feeding arthropods can harm their hosts in many ways, such as through direct tissue damage and anemia, but also by distracting hosts from foraging or watching for predators. Blood-borne pathogens transmitted by arthropods can further harm the host. Thus, effective behavioral and im...2014-01-01
72 Parkinson, John StansfieldAn unorthodox sensory adaptation site in the E. coli serine chemoreceptorThe serine chemoreceptor of E. coli contains four canonical methylation sites for sensory adaptation that lie near inter-subunit helix interfaces of the Tsr homodimer. An unexplored fifth methylation site, E502, lies at an intra-subunit helix interface, closest to the HAMP domain that controls input...2014-01-01
73 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
74 Sperry, John S.Analysis of circular bordered pit function II. Gymnosperm tracheids with torus-margo pit membranesA model of xylem conduit function was applied to gymnosperm tracheids with torus-margo pit membranes for comparison with angiosperm vessels. Tracheids from 17 gymnosperm tree species with circular bordered pits and air-seed pressures from 0.8 to 11.8 MPa were analyzed. Tracheids were more reinforced...Functional wood anatomy; hydraulic architecture; plant biomechanics2004
75 Beckerle, Mary C.Analysis of the roles of microtubules and actin in erythrophore intracellular motilityThe Holocentrus erythrophore, a red pigment cell, represents a model system for the study of organized intracellular transport. We have investigated the possibility that microtubules and actin are integral components of the pigment translocating motility machine.Actin; Actomyosin; Erythrophore; Pigment1983
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