4,970 research outputs found
Nonadiabatic Electronic Interactions In The Ion-Pair States Of NelCl
Nonadiabatic interactions in the NeIC1 van der Waals complex have been explored in the lowest energy triad of IC1 ion-pair states (approximately 39 000 cm-1). Dispersed fluorescence measurements reveal emission characteristic of multiple ion-pair electronic states, with the relative contributions from the E(O+ ), beta(1), and D\u27(2) states changing with the initial IC1 vibrational excitation (v(IC1)). Emission directly from NeIC1 (v(IC1) = O) complexes indicates that the initially prepared NeIC1 levels have mixed electronic character and that the IC1 electronic parentage changes with the initial van der Waals vibrational level selected. NeIC1 complexes prepared with 1-4 quanta of IC1 stretch undergo rapid vibrational predissociation with a strong propensity for DELTA-V(IC1) = - 1 relaxation. The electronic state(s) populated in the IC1 fragments differ from the mixed electronic character of the initially prepared level, demonstrating that vibrational predissociation is accompanied by nonadiabatic electronic state changing processes. The observed final state selectivity may be attributed to the relative strength of the nonadiabatic couplings between the initial NeIC1 bound state and the final IC1 states or a momentum gap rationale based on the overlap between the NeIC1 bound state wave function and the highly oscillatory continuum wave function of the separating fragments
Second OH Overtone Excitation And Statistical Dissociation Dynamics Of Peroxynitrous Acid
The second OH overtone transition of the trans-perp conformer of peroxynitrous acid (tp-HOONO) is identified using infrared action spectroscopy. HOONO is produced by the recombination of photolytically generated OH and NO(2) radicals, and then cooled in a pulsed supersonic expansion. The second overtone transition is assigned to tp-HOONO based on its vibrational frequency (10 195.3 cm(-1)) and rotational band contour, which are in accord with theoretical predictions and previous observations of the first overtone transition. The transition dipole moment associated with the overtone transition is rotated considerably from the OH bond axis, as evident from its hybrid band composition, indicating substantial charge redistribution upon OH stretch excitation. The overtone band exhibits homogeneous line broadening that is attributed to intramolecular vibrational redistribution, arising from the coupling of the initially excited OH stretch to other modes that ultimately lead to dissociation. The quantum state distributions of the OH X (2)Pi (nu=0) products following first and second OH overtone excitation of tp-HOONO are found to be statistical by comparison with three commonly used statistical models. The product state distributions are principally determined by the tp-HOONO binding energy of 16.2(1) kcal mol(-1). Only a small fraction of the OH products are produced in nu=1 following the second overtone excitation, consistent with statistical predictions
An evaluation of subjective experiences, effects and overall satisfaction with clozapine treatment in a UK forensic service
Objectives: Patients prescribed clozapine were surveyed to assess (a) the effects, both positive and adverse, and overall satisfaction with clozapine in comparison to previously prescribed antipsychotics and (b) the relative significance of effects experienced, both positive and adverse, in terms of impact on subjective well-being.
Methods: A total of 56 male patients prescribed clozapine at a forensic psychiatric hospital were surveyed using a 27-item questionnaire. All patients had been prescribed clozapine for a minimum of 3 months. Respondents were asked to rate effects and satisfaction with clozapine treatment in comparison with previously prescribed antipsychotic medication on a five-point scale. Respondents were also asked to rate effects experienced with clozapine treatment in terms of impact on subjective well-being on a five-point scale.
Results: A total of 89% of respondents reported greater satisfaction with clozapine than with previously prescribed antipsychotic medication. A majority of patients reported positive effects in terms of an improvement in their quality of life (68%) and social abilities (52%) with clozapine in comparison with previously prescribed antipsychotics. Nocturnal hypersalivation (84%) and weight gain (57%) were the most common adverse effects. Hedonic responses were assessed for each effect in order to determine the associated subjective experiences. The most positive hedonic responses were for quality of life, mood and alertness. In terms of adverse impact on subjective well-being, nocturnal hypersalivation ranked highest.
Conclusions: Patients in a UK forensic sample are largely satisfied with clozapine treatment. The subjective effects of clozapine treatment should be taken into account by clinicians when assessing response. This may provide an opportunity to highlight the positive changes and prioritize management of the most undesirable adverse effects, which is likely to promote compliance and improve longer term treatment outcomes
The separation of the particle and light fronts in cosmic ray showers at mountain altitudes
This Thesis describes a study of the time separation of the Cerenkov light and particle fronts in large (10(^16) - 10(^18) eV) cosmic ray air showers at an atmospheric depth of 862 g cm(^-2). The work formed only part of a much larger experiment conducted at the Dugway Proving Ground, Utah, U.S.A. during the autumn and winter months of 1977/8, 1978/79, 1979/80. The aim of this particular work is to refine our understanding of the time delay between the Cerenkov light and the particle fronts, and to establish this time as a depth of maximum sensitive measure. Since this is a prime indicator of the mass of the initiating primary, the time delay which can be readily measured may yield a method of estimating the primary mass of energetic cosmic rays. An account of earlier measurements of Cerenkov radiation is given as well as a theoretical treatment of the time separation based on computer simulations of showers. The experimental results are presented which demonstrate a sensitivity to cascade development and recommendations for future time separation studies are made
Extended Bose-Hubbard model with incompressible states at fractional numbers
The Bose-Hubbard model is extended to include nearest and far neighbor
interactions and is related to the fractional quantum Hall effect (FQHE). Both
models may be studied in optical lattices with quantum gases. The ground state
is calculated for the extended Bose-Hubbard model with strong repulsive
interactions (weak hopping). Incompressible Mott insulator states are found at
rational filling fractions compatible with the principal and secondary FQHE
filling fractions of the lowest Landau levels observed experimentally. It is
discussed to which extent these states at fractional filling survive or
undergoes a Mott insulator transition to a superfluid as hopping terms are
included.Comment: Revised version, to appear in PR
A cohort study of duplex Doppler examinations of the carotid artery in primary open angle glaucoma
Objectives To explore the possibility of pathological change in the common carotid artery at the bifurcation and in the internal carotid artery beyond the bifurcation which could contribute to a reduced diastolic pressure as observed in primary open angle glaucoma.
Design Duplex ultrasonic examinations of carotid bifurcations were conducted on 80 patients. Carotid artery defects were allocated into three types: no demonstrable flow defects, internal carotid artery abnormalities and disease in the carotid bulb.
Setting Bristol Royal Infirmary Vascular Laboratory.
Participants Eighty patients (mean age 69.6 years) providing a total of 160 sides to the analysis.
Main outcome measures An estimated central retinal artery pressure, intraocular pressure and field loss were recorded for each side measured.
Results Doppler investigations revealed significant levels of pathological change in the internal carotid distinct from changes at the carotid bulb. The disease revealed in the internal carotid artery was significantly associated with intraocular pressure (p = 0.032), with an effect small to medium in magnitude. The Q2 measure, derived from mean arterial pressure and intraocular pressure, was also substantively associated with disease in the internal carotid artery. Both intraocular pressure and the Q2 measure effectively discriminated between groups, with field loss providing rather less discriminating capability. There was a strong trend towards a higher intraocular pressures and a greater visual field loss with internal carotid artery disease.
Conclusions Pathological changes in the extra cranial carotid artery in primary open angle glaucoma exceed those in the arteries classified as normal. The presence of disease specifically in the internal carotid artery emphasised the need for a mechanism for the evaluation of the internal carotid apart from the carotid bulb. A basis for clarifying the presence of an ischaemic zone is proposed
Reactive Quenching Of Od A (2)Σ(+) By H-2: Translational Energy Distributions For H- And D-Atom Product Channels
The H- and D-atom products from collisional quenching of OD A (2)Sigma(+) by H-2 are characterized through Doppler spectroscopy using two-photon (2 S-2 \u3c-\u3c- 1 S-2) laser-induced fluorescence. Partial deuteration enables separation of the channel forming H + HOD products, which accounts for 75% of reactive quenching events, from the D + H2O product channel. The Doppler profiles, along with those reported previously for other isotopic variants, are transformed into product translational energy distributions using a robust fitting procedure based on discrete velocity basis functions. The product translational energy distribution for the H- atom channel is strongly peaked at low energy (below 0.5 eV) with a long tail extending to the energetic limit. By contrast, the D-atom channel exhibits a small peak at low translational energy with a distinctive secondary peak at higher translational energy (approximately 1.8 eV) before falling off to higher energy. In both cases, most of the available energy flows into internal excitation of the water products. Similar distributions are obtained upon reanalysis of D- and H- atom Doppler profiles, respectively, from reactive quenching of OH A (2)Sigma(+) by D-2. The sum of the translational energy distributions for H- and D- atom channels is remarkably similar to that obtained for OH A (2)Sigma(+) + H-2, where the two channels cannot be distinguished from one another. The product translational energy distributions from reactive quenching are compared with those obtained from a previous experiment performed at higher collision energy, quasiclassical trajectory calculations of the post-quenching dynamics, and a statistical model. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3644763
A natural study of the efficacy of replacement medications for the treatment of clozapine-induced hypersalivation
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