490 research outputs found

    An ab initio variationally computed room-temperature line list for (32)S(16)O3

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    Ab initio potential energy and dipole moment surfaces are computed for sulfur trioxide (SO3) at the CCSD(T)-F12b level of theory with appropriate triple-zeta basis sets. The analytical representations of these surfaces are used, with a slight correction, to compute pure rotational and rotation-vibration spectra of (32)S(16)O3 using the variational nuclear motion program TROVE. The calculations considered transitions in the region 0-4000 cm(-1) with rotational states up to J = 85. The resulting line list of 174,674,257 transitions is appropriate for modelling room temperature (32)S(16)O3 spectra. Good agreement is found with the observed infrared absorption spectra and the calculations are used to place the measured relative intensities on an absolute scale. A list of 10,878 experimental transitions is provided in a form suitable for inclusion in standard atmospheric and planetary spectroscopic databases

    ExoMol molecular line lists - XVII. The rotation-vibration spectrum of hot SO3

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    Sulphur trioxide (SO3) is a trace species in the atmospheres of the Earth and Venus, as well as being an industrial product and an environmental pollutant. A variational line list for 32S16O3, named UYT2, is presented containing 21 billion vibration–rotation transitions. UYT2 can be used to model infrared spectra of SO3 at wavelengths longwards of 2 μm (ν < 5000 cm−1) for temperatures up to 800 K. Infrared absorption cross-sections recorded at 300 and 500 C are used to validate the UYT2 line list. The intensities in UYT2 are scaled to match the measured cross-sections. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com

    ExoMol molecular line lists - XIV: The rotation-vibration spectrum of hot SO2

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    Sulphur dioxide is well-known in the atmospheres of planets and satellites, where its presence is often associated with volcanism, and in circumstellar envelopes of young and evolved stars as well as the interstellar medium. This work presents a line list of 1.3 billion 32S 16O2 vibration-rotation transitions computed using an empirically-adjusted potential energy surface and an ab initio dipole moment surface. The list gives complete coverage up to 8000 cm−1 (wavelengths longer than 1.25 µm) for temperatures below 2000 K. Infrared absorption cross sections are recorded at 300 and 500 C are used to validated the resulting ExoAmes line list. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com

    Molecular identification of CTX-M and blaOXY/K1 β-lactamase genes in Enterobacteriaceae by sequencing of universal M13-sequence tagged PCR-amplicons

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    <p>Abstract</p> <p>Background</p> <p>Plasmid encoded <sup><it>bla</it></sup>CTX-M enzymes represent an important sub-group of class A β-lactamases causing the ESBL phenotype which is increasingly found in <it>Enterobacteriaceae </it>including <it>Klebsiella </it>spp. Molecular typing of clinical ESBL-isolates has become more and more important for prevention of the dissemination of ESBL-producers among nosocomial environment.</p> <p>Methods</p> <p>Multiple displacement amplified DNA derived from 20 <it>K. pneumoniae </it>and 34 <it>K. oxytoca </it>clinical isolates with an ESBL-phenotype was used in a universal CTX-M PCR amplification assay. Identification and differentiation of <sup><it>bla</it></sup>CTX-M and <sup><it>bla</it></sup>OXY/K1 sequences was obtained by DNA sequencing of M13-sequence-tagged CTX-M PCR-amplicons using a M13-specific sequencing primer.</p> <p>Results</p> <p>Nine out of 20 <it>K. pneumoniae </it>clinical isolates had a <sup><it>bla</it></sup>CTX-M genotype. Interestingly, we found that the universal degenerated primers also amplified the chromosomally located K1-gene in all 34 <it>K. oxytoca </it>clinical isolates. Molecular identification and differentiation between <sup><it>bla</it></sup>CTX-M and <sup><it>bla</it></sup>OXY/K1-genes could only been achieved by sequencing of the PCR-amplicons. <it>In silico </it>analysis revealed that the universal degenerated CTX-M primer-pair used here might also amplify the chromosomally located <sup><it>bla</it></sup>OXY and K1-genes in <it>Klebsiella </it>spp. and K1-like genes in other <it>Enterobacteriaceae</it>.</p> <p>Conclusion</p> <p>The PCR-based molecular typing method described here enables a rapid and reliable molecular identification of <sup><it>bla</it></sup>CTX-M, and <sup><it>bla</it></sup>OXY/K1-genes. The principles used in this study could also be applied to any situation in which antimicrobial resistance genes would need to be sequenced.</p

    Reduction in downstream test utilization following introduction of coronary computed tomography in a cardiology practice

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    To compare utilization of non-invasive ischemic testing, invasive coronary angiography (ICA), and percutaneous coronary intervention (PCI) procedures before and after introduction of 64-slice multi-detector row coronary computed tomographic angiography (CCTA) in a large urban primary and consultative cardiology practice. We utilized a review of electronic medical records (NotesMD®) and the electronic practice management system (Megawest®) encompassing a 4-year period from 2004 to 2007 to determine the number of exercise treadmill (TME), supine bicycle exercise echocardiography (SBE), single photon emission computed tomography (SPECT) myocardial perfusion stress imaging (MPI), coronary calcium score (CCS), CCTA, ICA, and PCI procedures performed annually. Test utilization in the 2 years prior to and 2 years following availability of CCTA were compared. Over the 4-year period reviewed, the annual utilization of ICA decreased 45% (2,083 procedures in 2004 vs. 1,150 procedures in 2007, P < 0.01) and the percentage of ICA cases requiring PCI increased (19% in 2004 vs. 28% in 2007, P < 0.001). SPECT MPI decreased 19% (3,223 in 2004 vs. 2,614 in 2007 P < 0.02) and exercise stress treadmill testing decreased 49% (471 in 2004 vs. 241 in 2007 P < 0.02). Over the same period, there were no significant changes in measures of practice volume (office and hospital) or the annual incidence of PCI (405 cases in 2004 vs. 326 cases in 2007) but a higher percentage of patients with significant disease undergoing PCI 19% in 2004 vs. 29% in 2007 P < 0.01. Implementation of CCTA resulted in a significant decrease in ICA and a corresponding significant increase in the percentage of ICA cases requiring PCI, indicating that CCTA resulted in more accurate referral for ICA. The reduction in unnecessary ICA is associated with avoidance of potential morbidity and mortality associated with invasive diagnostic testing, reduction of downstream SPECT MPI and TME as well as substantial savings in health care dollars

    Could chiropractors screen for adverse drug events in the community? Survey of US chiropractors

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    Abstract Background The "Put Prevention into Practice" campaign of the US Public Health Service (USPHS) was launched with the dissemination of the Clinician's Handbook of Preventive Services that recommended standards of clinical care for various prevention activities, including preventive clinical strategies to reduce the risk of adverse drug events. We explored whether nonprescribing clinicians such as chiropractors may contribute to advancing drug safety initiatives by identifying potential adverse drug events in their chiropractic patients, and by bringing suspected adverse drug events to the attention of the prescribing clinicians. Methods Mail survey of US chiropractors about their detection of potential adverse drug events in their chiropractic patients. Results Over half of responding chiropractors (62%) reported having identified a suspected adverse drug event occurring in one of their chiropractic patients. The severity of suspected drug-related events detected ranged from mild to severe. Conclusions Chiropractors or other nonprescribing clinicians may be in a position to detect potential adverse drug events in the community. These detection and reporting mechanisms should be standardized and policies related to clinical case management of suspected adverse drug events occurring in their patients should be developed
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