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  • 1
    Electronic Resource
    Electronic Resource
    Optimal control of unimolecular reactions in the collisional regime (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 94 (1991), S. 1158-1166 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The possibility of controlling unimolecular–dissociation processes with multiple laser fields in the collisional regime is examined. Employing the Bloch equations to describe optical excitation and decay processes, optimal control theory is used to design amplitude modulated fields which produce the desired excited-state products. The selectivity of the product distribution of a simple four-state photodissociation system is shown to have a square-root dependence on the relative value of the mean dephasing time T2 to the pulse length τ, i.e, (T2/τ)1/2. The equivalence between T2 decay and phase disruptions occurring in a random-walk fashion is also examined. In the Appendix it is shown that the essential effect of the system temperature is to introduce a Boltzmann population factor on the product selectivity without affecting the nature of the optimal field.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.460022
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  • 2
    Electronic Resource
    Electronic Resource
    Police-Public Interactions: The Impact of Conflict Resolution Tactics (1994)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of applied social psychology 24 (1994), S. 0 
    Details
    ISSN: 1559-1816
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Psychology
    Notes: Following Hammock and Richardson (1992), it was hypothesized that a preference among some police officers for confrontational rather than conciliatory tactics when dealing with the public may serve to escalate a conflict and thereby explain the documented individual differences in reports of officer assaults. In order to test this possibility, preferred conflict tactics and officers' recent experiences of citizen compliance (and non-compliance) were measured for a sample of 115 English police and 48 Australian police. The results supported the hypothesized relationship by indicating a significant correlation between preferences for specific confrontational and coercive tactics and experiences of noncompliance from the public.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1559-1816.1994.tb00563.x
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  • 3
    Electronic Resource
    Electronic Resource
    Comparison of clinical indicators for performance measurement of health care quality: a cautionary note (2000)
    Bradford : Emerald
    Clinical performance and quality health care 8 (2000), S. 202-211 
    Details
    ISSN: 1063-0279
    Source: Emerald Fulltext Archive Database 1994-2005
    Topics: Medicine
    Notes: The use of clinical performance data is increasing rapidly. Yet, substantial variation exists across indicators designed to measure the same clinical event. We compared indicators from several indicator measurement systems to determine the consistency of results. Five measurement systems with well-defined indicators were selected. They were applied to 24 hospitals. Indicators for mortality from coronary artery bypass graft surgery and mortality in the perioperative period were chosen from these measurement systems. Analyses results and concludes that it is faulty to assume that clinical indicators derived from different measurement systems will give the same rank order. Widespread demand for external release of outcome data from hospitals must be balanced by an educational effort about the factors that influence and potentially confound reported rates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1108/14664100010361755
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  • 4
    Electronic Resource
    Electronic Resource
    Optimally controlled five-laser infrared multiphoton dissociation of HF (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 100 (1994), S. 4211-4228 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Simulations of the quantum dynamics of the HF molecule immersed in a field of five overlapping, intense, linearly polarized, infrared laser pulses of subpicosecond duration are performed. The HF molecule, initially in its ground state, is modeled as a rotating oscillator interacting with a classical laser field via electric dipole interaction. Realistic potential and dipole functions are used. Optimal overlaps of the five laser pulses, as well as the optimal carrier frequencies of the laser pulses, are found which maximize the HF dissociation yield. A maximal yield of 45% in a single combined pulse is achieved using the best available potential and dipole moment functions. The optimal infrared multiphoton dissociation pathway for the HF molecule includes a series of the Δv=1 vibrational-rotational transitions followed by a series of Δv≥2 vibrational-rotational transitions. The latter is necessary as a consequence of the vanishing Δv=1 transition moment around v=12. In the Δv=1 regime, both P and R branch transitions are found to be important. The angular distribution of the dissociative flux is computed. Robustness of the results with respect to changes in the interatomic potentials, dipole functions and reduced mass, as well as to changes in laser pulse parameters (carrier frequencies, timings, phases, field amplitudes, and pulse durations) is investigated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.466305
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  • 5
    Electronic Resource
    Electronic Resource
    Femtosecond photoassociation: Coherence and implications for control in bimolecular reactions (1997)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 106 (1997), S. 8013-8021 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A theoretical analysis of the recent femtosecond photoassociation spectroscopy (FPAS) experiment on mercury [U. Marvet and M. Dantus, Chem. Phys. Lett. 245, 393 (1995)] is presented. It is shown that when a thermal distribution of diatom collision pairs is excited from a free to a bound electronic state on a time scale shorter than molecular vibration, an ensemble of coherent wave packets is produced. The dynamics of these wave packets created by the photoassociation pulse can be observed by firing a second probe pulse at variable time delays, and the depletion of the first excited bound state by the probe pulse is detected via fluorescence of the remaining population. Simulations of the FPAS experiment, using both wave packet propagation techniques and perturbation theory, clearly show the vibrational dynamics of the photoassociated transients. It is also demonstrated how the FPAS technique may be used as a tool for controlling the energy, impact parameter, and orientation in bimolecular reactions. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.473811
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  • 6
    Electronic Resource
    Electronic Resource
    Initial state laser control of curve-crossing reactions using the Rayleigh–Ritz variational procedure (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 7045-7051 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A new two-step procedure for laser control of photodissociation is presented. In the first step of the procedure, we show that control of photodissociation product yields can be exerted through preparation of the initial wave function prior to application of the photodissociation field in contrast to previous laser control studies where attention has focused on the design of the field which induces dissociation. Specifically, for a chosen channel from which maximum product yield is desired and a given photodissociation field, the optimal linear combination of vibrational eigenstates which comprise the initial wave function is found using a straightforward variational calculation. Any photodissociation pulse shape and amplitude can be assumed since the Schrödinger equation is solved directly. Application of this method to control of product yields in the photodissociation of hydrogen iodide is demonstrated. The second step of the control procedure involves the preparation of the coherent superposition of discrete levels obtained from the previous step; design of the preparatory field can be done analytically for two or three level systems as demonstrated here or with other well-studied iterative field design methods. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.471421
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  • 7
    Electronic Resource
    Electronic Resource
    External field control of condensed phase reactions (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 4843-4851 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Control of tunneling in a symmetric double well coupled to a bath via an external field is demonstrated. Optimal control theory is employed to design a laser field which couples to the reaction coordinate and drives a localized wave packet on the reactant side to the product side at a specified target time τ. Both a very quantumlike system (high barrier) and a low barrier double well are examined; excellent results are obtained for a range of reduced bath viscosities. Analysis of the control fields and corresponding localization dynamics shows that the frequency components of the control field are more or less in resonance with eigenstates of the double well and that the laser field enhances the natural dynamics of the individual wells. Future extension to more complicated models where the field couples to the bath is discussed. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.477095
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  • 8
    Electronic Resource
    Electronic Resource
    On the generality of optimal control theory for laser-induced control field design (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 105 (1996), S. 1299-1300 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Optimal control theory is argued to be the most general method for designing fields used to induce desired chemical reactions. Other "schemes'' for field design which constrain the field form and introduce limiting dynamical assumptions are shown to be particular solutions of the more general optimal control theory (OCT). © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.471967
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  • 9
    Electronic Resource
    Electronic Resource
    Prospects for urinary proteomics: Exosomes as a source of urinary biomarkers (Review Article) (2005)
    Melbourne, Australia : Blackwell Science Pty
    Nephrology 10 (2005), S. 0 
    Details
    ISSN: 1440-1797
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: SUMMARY:  Recent progress in biotechnology offers the promise of better medical care at lower costs. Among the techniques that show the greatest promise is mass spectrometry of proteins, which can identify proteins present in body fluids and tissue specimens at a large scale. Because urine can be collected in large amounts in a non-invasive fashion, the potential exists to use mass spectrometry to discover urinary biomarkers that are early predictors of renal disease, or useful in making therapeutic choices. Recently, the authors demonstrated that both membrane proteins and cytosolic proteins from renal epithelia are highly enriched in low-density urinary structures identified as exosomes. Exosomes were found to contain many disease-associated proteins including aquaporin-2, polycystin-1, podocin, non-muscle myosin II, angiotensin-converting enzyme, Na+K+2Cl- cotransporter (NKCC2), thiazide-sensitive Na-Cl cotransporter (NCC), and epithelial sodium channel (ENaC). Potentially, other disease biomarkers could be discovered by mass spectrometry-based proteomic studies in well-defined patient populations. Herein is described the advantages of using urinary exosomes as a starting material for biomarker discovery. In addition, the purpose of this review is to present an overall strategy for biomarker discovery in urine using exosomes and for developing cost-effective clinical assays for these biomarkers, which can potentially be used for early detection of disease, as a means of differential diagnosis, or as a means of guiding therapy. Finally, potential barriers that need to be overcome before urinary proteomics can be applied clinically, are emphasized.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1440-1797.2005.00387.x
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  • 10
    Electronic Resource
    Electronic Resource
    Teaching lasers to control molecules in the presence of laboratory field uncertainty and measurement imprecision (1993)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 98 (1993), S. 4557-4566 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: An iterative optimization algorithm for designing laser fields to control molecular motion which utilizes laboratory input (test fields) and output (resulting product yields) information is proposed. Laboratory uncertainties such as laser field noise and limited precision in the product yield measurements are included in the simulations of the experiments. Two simulated examples of implementation of the algorithm are presented: selective electronic excitation in a model four-state system and maximizing dissociation yield of the hydrogen fluoride molecule. Both examples demonstrate that, even with the inclusion of laboratory uncertainties, the experimental learning-based algorithm is a potentially feasible method of controlling molecular motion and possibly manipulating chemical reactions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.465017
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