Reaction Probabilities (reaction + probability)

Distribution by Scientific Domains


Selected Abstracts


Evaluation of Naranjo Adverse Drug Reactions Probability Scale in causality assessment of drug-induced liver injury

ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2008
M. GARCÍA-CORTÉS
Summary Background, Causality assessment in hepatotoxicity is challenging. The current standard liver-specific Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method scale is complex and difficult to implement in daily practice. The Naranjo Adverse Drug Reactions Probability Scale is a simple and widely used nonspecific scale, which has not been specifically evaluated in drug-induced liver injury. Aim, To compare the Naranjo method with the standard liver-specific Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method scale in evaluating the accuracy and reproducibility of Naranjo Adverse Drug Reactions Probability Scale in the diagnosis of hepatotoxicity. Methods, Two hundred and twenty-five cases of suspected hepatotoxicity submitted to a national registry were evaluated by two independent observers and assessed for between-observer and between-scale differences using percentages of agreement and the weighted kappa (,w) test. Results, A total of 249 ratings were generated. Between-observer agreement was 45% with a ,w value of 0.17 for the Naranjo Adverse Drug Reactions Probability Scale, while there was a higher agreement when using the Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method scale (72%, ,w: 0.71). Concordance between the two scales was 24% (,w: 0.15). The Naranjo Adverse Drug Reactions Probability Scale had low sensitivity (54%) and poor negative predictive value (29%) and showed a limited capability to distinguish between adjacent categories of probability. Conclusion, The Naranjo scale lacks validity and reproducibility in the attribution of causality in hepatotoxicity. [source]


Quantum wave packet calculation of reaction probabilities, cross sections, and rate constants for the C(1D) + HD reaction

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 5 2005
Fahrettin Gogtas
Abstract The time-dependent real wave packet method has been used to study the C(1D) + HD reaction. The state-to-state and state-to-all reactive scattering probabilities for a broad range of energies are calculated at zero total angular momentum. The probabilities for J > 0 are estimated from accurately computed J = 0 probabilities by using the J -shifting approximation. The integral cross sections for a large energy range, and thermal rate constants are calculated. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [source]


Time-dependent quantum study of H(2S) + FO(2,) , OH(2,) + F(2P) reaction on the 13A, and 13A, states

JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 14 2010
Fahrettin Gogtas
Abstract The dynamics of the H(2S) + FO(2,) , OH(2,) + F(2P) reaction on the adiabatic potential energy surface of the 13A, and 13A, states is investigated. The initial state selected reaction probabilities for total angular momentum J = 0 have been calculated by using the quantum mechanical real wave packet method. The integral cross sections and initial state selected reaction rate constants have been obtained from the corresponding J = 0 reaction probabilities by means of the simple J -Shifting technique. The initial state-selected reaction probabilities and reaction cross section do not manifest any sharp oscillations and the initial state selected reaction rate constants are sensitive to the temperature. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010 [source]


Examination of intermediate species in GaN metal-organic vapor-phase epitaxy by selective-area growth

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7-8 2010
Masakazu Sugiyama
Abstract The major reactive intermediate species of GaN has been deduced and its surface reaction rate constant has been obtained through the analysis of multi-scale growth-rate profiles both in the reactor-scale and in the micrometer-scale that were obtained by selective-area growth. Usually, it is difficult to explore surface reaction kinetics, especially for metal-organic vapour phase epitaxy (MOVPE), because of mass-transfer-limited kinetics. This multi-scale analysis, however, has clarified that a single precursor, a gas-phase reaction product between (CH3)3Ga and NH3, leads to the growth of GaN with a surface reaction probability of approximately 0.4 at 1400 K which is a typical growth temperature of GaN. Contribution of higher-order polymers was not significant in growth rate, but they seemed to be a cause of degraded surface morphology. A lumped reaction model of GaN MOVPE was proposed that led to reasonable agreement between a simulated growth-rate profile in the reactor-scale and a corresponding measured profile, which would lead to improved design of reactors and growth conditions. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


An analysis of photopolymerization kinetics and stress development in multifunctional acrylate coatings

POLYMER ENGINEERING & SCIENCE, Issue 2 2001
Andrei A. Stolov
Polymerization kinetics and stress buildup of multifunctional acrylic coatings have been studied simultaneously using a cantilever deflection method and real time one-bounce infrared reflectance spectroscopy. Cantilever deflection due to stress buildup in the film is correlated with crosslink density in the polymerizing mass. Stress buildup was observed not to occur instantaneously after radiation was introduced but rather after a certain time interval. The time delay between onset of polymerization and initiation of stress indication is attributed to the introduction of crosslinks, leading to a gel state. The measured stress-conversion relationship can be predicted using an approach incorporating monomer reaction probability. Stress buildup can vary considerably as a function of processing conditions such as film thickness, temperature at solidification point, and the type, concentration and absorptivity of photoinitiator, which govern the degree of crosslinking. Under certain processing conditions, an uneven distribution of the monomer conversion in the film may severely alter the stress-film thickness relationship. In some cases the cantilever material anisotropy can be detected based on the cantilever deflection measured. [source]