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  • 1
    Electronic Resource
    Electronic Resource
    Methods for molecular dynamics with nonadiabatic transitions (1995)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 102 (1995), S. 496-510 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We show how the dynamically nonlocal formulation of classical nuclear motion in the presence of quantal electronic transitions presented many years ago by P. Pechukas [Phys. Rev. 181, 166 (1969); 181, 174 (1969)] can be localized in time using time dependent perturbation theory to give an impulsive force which acts when trajectories hop between electronic surfaces. The action of this impulsive force is completely equivalent to adjusting the nuclear velocities in the direction of the nonadiabatic coupling vector so as to conserve energy, a procedure which is widely used in surface hopping trajectory methods [J. C. Tully, J. Chem. Phys. 93, 1061 (1990)]. This is the first time the precise connection between these two formulations of the nonadiabatic dynamics problem has been considered. We also demonstrate that the stationary phase approximation to the reduced propagator at the heart of Pechukas' theory is not unitary due to its neglect of nonstationary paths. As such mixed quantum-classical evolution schemes based on this approximation are not norm conserving and in general must fail to give the correct branching between different competing electronic states. Tully's phase coherent, fewest switches branching algorithm is guaranteed to conserve the norm. The branching between different alternatives predicted by this approach, however, may be inaccurate, due to use of the approximate local dynamics. We explore the relative merits of these different approximations using Tully's 1D two state example scattering problems for which numerically exact results are easily obtained. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.469428
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  • 2
    Electronic Resource
    Electronic Resource
    Calculation of the rotational Raman spectrum of H2 in ice (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 105 (1996), S. 3938-3941 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Calculation of the rotational Raman spectrum of H2 in ice Ih is reported using previously developed nonadiabatic correlation function methods and accurate potentials. We explore the importance of the quantal treatment of the H2 center-of-mass translational motion. Calculated rotational Raman linewidths quantitatively reproduce experimental results. Observed differences in trends in bandwidth for liquid and solid phases are understood in terms of time scale and strength of dynamical mixing of rotational states. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.472266
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  • 3
    Electronic Resource
    Electronic Resource
    Nonadiabatic dynamical studies of the rotational Raman spectrum of H2 in water (1995)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 102 (1995), S. 1107-1113 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The rotational Raman spectrum of H2 in liquid H2O and D2O have been calculated using our nonadiabatic time correlation function results presented in earlier work [L. Xiao and D. F. Coker, J. Chem. Phys. 100, 8646 (1994)]. The rotational potential experienced by the H2 molecule in this solvent environment is so anisotropic that classical solvent fluctuations not only drive transitions between orientational basis states, but mixing of states from different total angular momentum levels is also considerable. Our nonadiabatic calculations are able to quantitatively reproduce the experimental rotational Raman line shapes and their trends with solvent isotopic substitution. We demonstrate that nonadiabatic transitions between adiabatic rotor states play a key role in smoothing out artificial structures predicted in the static and adiabatic limit spectra. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.469168
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  • 4
    Electronic Resource
    Electronic Resource
    Nitric Oxide Synthase Pathway May Mediate Human Natural Killer Cell Cytotoxicity (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Scandinavian journal of immunology 42 (1995), S. 0 
    Details
    ISSN: 1365-3083
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The present study provides evidence that the human natural killer (NK) cell effector mechanism causing target cytolysis has a requirement for L-arginine. In a deficient medium (DM) containing only salts, buffer system and glucose, NK cell-mediated cytotoxicity was found to decrease by 70% as compared to that obtained in a complete medium (CM). However, adding L-arginine to such DM could restore the activity of NK cells to the normal level. Many other components of CM, such as serum, glutamine and vitamins did not improve NK cell-mediated killing in DM. When all amino acids except L-arginine were added to DM only a partial recovery of NK cell functional cytolysis was seen. L-arginine enhanced the NK cell activity in a dose-dependent manner. Additionally, the inhibitor of both inducible and constitutive nitric oxide synthase, N-monomethyl-L-arginine (L-NMMA) inhibited NK cytolytic activity in DM supplemented with L-arginine indicating participation of nitric oxide (NO). The results also show that the stimulatory effect of L-arginine on human NK cell-mediated cytotoxicity was accompanied by an increase in NO formation as determined by accumulation of nitrite and citrulline. L-NMMA gave a dose-dependent reduction in NO generation as well. The nitrite and citrulline production dose-dependenlly correlated with not only the concentration of L-arginine in the cultivation medium, but also the enhanced NK cell-mediated cytolysis. Taken together, these findings could define a L-arginine/NO-linked effector mechanism in human NK cells. Nitrite and citrulline were not formed when NK cell-mediated target cell killing took place in a L-arginine-free DM supplemented with additives. Thus, it appears as if human NK cells may cause target cell killing via both NO-dependent and -independent processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3083.1995.tb03687.x
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  • 5
    Electronic Resource
    Electronic Resource
    Efficient selection and regeneration of creeping bentgrass transformants following particle bombardment (1997)
    Springer
    Plant cell reports 16 (1997), S. 874-878 
    Details
    ISSN: 1432-203X
    Keywords: Key wordsAgrostis palustris Huds. ; Turfgrass ; Particle bombardment ; Stable transformation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have established an efficient genetic transformation system for creeping bentgrass (Agrostis palustris Huds.) using particle bombardment. The transformation was performed using the plasmid pZO1052 which contains the reporter β-glucuronidase (uidA) gene and the selectable marker hygromycin phosphotransferase (hph) gene. Transformed calli and plants were obtained via particle bombardment followed by selection of transformants on medium containing 200 mg/l of hygromycin. An average of 4.6 resistant colonies per bombardment were obtained. Southern analysis confirmed the integration of foreign genes in 19 of 21 putative transformants, indicating that selection by hygromycin was highly effective.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002990050337
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  • 6
    Electronic Resource
    Electronic Resource
    Thermal Decomposition of Fullerene Derivatives A Synthesis Method of New Fullerene Based Molecules (1999)
    Springer
    Journal of thermal analysis and calorimetry 56 (1999), S. 167-173 
    Details
    ISSN: 1572-8943
    Keywords: fullerene dimers ; [60]fullerene ; thermal decomposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The thermal decomposition of methano-fullerene derivatives such as ethoxycarbonyl methano[60] fullerene and various isomers of bis-(ethoxycarbonyl methano)[60] fullerene leads to new fullerene derivatives, which have been preliminary characterized. The analysis of separated species was performed by UV-VIS, IR, H- and C-NMR, STM, FAB, LDI and MALDI-TOF MS spectroscopy. One of the isolated phases is a C122 molecule with a dumbbell-like structure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1010120400419
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  • 7
    Electronic Resource
    Electronic Resource
    INAA of elemental contents in fingernails of esophageal cancer patients (1995)
    Springer
    Journal of radioanalytical and nuclear chemistry 195 (1995), S. 43-49 
    Details
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Fingernails of pathologically diagnosed normal people, light esophageal epitheliosis patients, severe esophageal epitheliosis patients and esophageal cancer patients were irradiated and their elemental contents were determined by INAA. Multivariate statistical treatment of Ca, Cl, K. Mg, Se and Zn data shows that esophageal cancer patients are distinguishable from non-cancer patients. The accuracy computed by neural networks is greater than 80%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02036471
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  • 8
    Electronic Resource
    Electronic Resource
    Production and application of isotopes in China (1996)
    Springer
    Journal of radioanalytical and nuclear chemistry 205 (1996), S. 9-20 
    Details
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract The research, development and production of isotopes and their products have made great progress in the past years. A comprehensive nuclear industry has been established. At present, isotope-and radiation technology has been developed rapidly and applied extensively in many fields such as agriculture, industry and medicine in China. Some successful projects have generated considerable economical and social benefits. Organized efforts are being made to ensure continuing research and development of isotope and radiation technologies to meet the challenges and opportunities in the turn of the century.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02040544
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  • 9
    Electronic Resource
    Electronic Resource
    HPLC analysis of radiolabeled octreotide (1998)
    Springer
    Journal of radioanalytical and nuclear chemistry 236 (1998), S. 205-207 
    Details
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Radiolabeled somatostatin analogue is a useful ligand for scintigraphic imaging of somatostatin receptor-bearing tumors. In this study, we investigated the effects of different radiolabeling conditions on labeling yield and ratio between mono-iodinated and di-iodinated125I-Tyr3-octreotide by HPLC analysis. In vitro and in vivo stabilities of125I-Tyr3-octreotide and111In-DTPA-D-Phe1-octreotide were also determined. Both radiolabeled compounds were relatively stable in vitro, but were decomposed to free125I− and111In-DTPA in vivo, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02386343
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  • 10
    Electronic Resource
    Electronic Resource
    Social Organization and Range Use in the Yunnan Snub-Nosed Monkey Rhinopithecus bieti (1998)
    Springer
    International journal of primatology 19 (1998), S. 13-51 
    Details
    ISSN: 1573-8604
    Keywords: Rhinopithecus bieti ; Colobinae ; temperate primates ; social organization ; range use ; lichen-eating ; China
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We studied social organization, behavior, and range use of the Yunnan snub-nosed monkey (Rhinopithecus bieti) at Wuyapiya (99°12′E, 28°30′N, the People's Republic of China) over 12 months between May 1992 and June 1994. The Wuyapiya band contained ≥175 members and had two levels of social organization. At one level, the monkeys formed multifemale, one-male units (OMUs) similar to those of many other colobines. At another level, 15 to 18 OMUs traveled together in a cohesive band. Unlike the bands of other species of Rhinopithecus, the Wuyapiya band of R. bieti did not show seasonal fission–fusion, although some social behavior, such as male–male aggression, was seasonal. With regard to range use, the Wuyapiya band had a large home range and long daily travel distances compared with other colobines. Minimum range size in 1 year at Wuyapiya is 16.25 km 2 , although there is no asymptote for range size as a function of observation time. Range size for the Wuyapiya band is 25.25 km 2 over the 2-year study and appeared to cover 100 km 2 between 1985 and 1994. The primary food of R. bieti at Wuyapiya is lichens, which are ubiquitous in fir trees. The multitiered social organization of R. bieti appears to result from the interaction of food resource characters with the forces of mate competition, with band sizes based on female responses to the spatial and temporal characteristics of lichens and subdivisions within bands based on male competition for mates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020302809584
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