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Elisabet Ekman,1–3 Göran Petersson,2 Sven Tågerud,3 Martin Bäckström41Regional Pharmacovigilance Unit, R & D Centre Skåne, Skåne University Hospital, Lund, 2eHealth Institute, Linnaeus University, Kalmar, 3School of Natural Sciences, Linnaeus University, Kalmar, 4Regional Pharmacovigilance Unit, Division of Clinical Pharmacology, University Hospital of Umeå, Umeå, SwedenBackground: The purpose of this study was to investigate awareness among nurses regarding their new role as reporters of adverse drug reactions in Sweden and factors that may influence reporting by nurses.Methods: In 2007, all nurses were included in the adverse drug reaction reporting scheme in Sweden. A questionnaire was sent to 753 randomly selected nurses in September 2010.Results: Of the 453 (60%) responding nurses, 265 (58%) were aware that nurses were included in the reporting of adverse drug reactions. Sixty-one nurses (14%) stated that they had reported an adverse drug reaction. Fifteen percent (n = 70) of the respondents had received training about reporting of adverse drug reactions. Almost one third of these (n = 21, 30%) had reported an adverse drug reaction on at least one occasion. Among nurses without training, a smaller proportion (n = 40, 11%, P < 0.05) had reported an adverse drug reaction on at least one occasion. The two factors considered most important by nurses for reporting were the severity of the adverse drug reaction and if the reaction was to a newly approved drug. A majority of the nurses (n = 397, 88%) were interested in a training course in pharmacology as part of their ongoing professional development. One third (32%) of all nurses stated that one reason for not reporting a suspected adverse drug reaction was that the physician responsible did not regard the reaction necessary to report.Conclusion: We found that more than half of the study population of nurses in Sweden were aware of their new role as reporters of adverse drug reactions, but few of the responding nurses had reported an adverse drug reaction. Given that training seems to be associated with high reporting frequency, we suggest more training in pharmacovigilance for nurses.Keywords: adverse drug reporting systems, nurses, knowledge

Purpose: To analyse caries risk factors of 12-13-year-old children living in Laos, using the computer program Cariogram to illustrate the caries risk profile. In addition, to compare the results with a study performed in Sweden.Materials and Methods: One hundred Laotian and 392 Swedish children were included. Interviews were performed to obtain information on diet intake and fluoride use. Saliva was analysed for mutans streptococci, lactobacilli and secretion rate/buffering capacity. Oral hygiene was assessed using the Silness and Löe criteria. Caries prevalence was recorded according to WHO. The data were entered into the Cariogram to determine each child's caries risk, expressed as 'the chance of avoiding caries'. The children were divided into five risk groups.Results: Mean DMFT level of the Laotian children was 4.61 +/- 2.95 and 1.38 +/- 1.97 in the Swedish group. For the risk factors plaque amount, frequency of food intake, saliva secretion rate, buffering capacity and fluoride, the Laotian children had significantly less favourable values compared to the Swedes. Only 6% of Laotian children belonged to the Cariogram low risk group versus 40% of the Swedish children. The mean DMFT for the five Cariogram groups was (from low to high risk) 0.00, 3.00, 3.56, 5.66, 6.11 for the Lao children and 0.31, 1.39, 2.56, 3.03, 2.91 for the Swedish ones. The mean chance of avoiding caries was 37.3% for the Laotians and 69.2% for the Swedish children (p < 0.001).Conclusion: According to the 'opinion' of the Cariogram, the Laotian children demonstrated significantly higher caries risk than Swedish children. [ABSTRACT FROM AUTHOR]

The isomerization barrier of vinylidene to acetylene is studied using different levels of theory up to the 6s6p3d2f,4s2p1d atomic pair natural orbitals which established the CBS-QCI/(...3d2f) APNO model. Other levels of theory used are the Austin Model 1, restricted Hartree-Fock and second-order Moller-Plesset. The vinylidene isomerization should be viewed as two distinct processes, the hydrogen migration and the pi-bond formation, to be in agreement with the Hammond postulate.

The major source of error in most ab initio calculations of molecular energies is the truncation of the one-electron basis set. Extrapolation to the complete basis set second-order (CBS2) limit using the N-1 asymptotic convergence of N-configuration pair natural orbital (PNO) expansions can be combined with the use of relatively small basis sets for the higher-order (i.e., MP3, MP4, and QCI) correlation energy to develop cost effective computational models. Following this strategy, three new computational models denoted CBS-4, CBS-q, and CBS-Q, are introduced. The mean absolute deviations (MAD) from experiment for the 125 energies of the G2 test set are 2.0, 1.7, and 1.0 kcal/mol, respectively. These results compare favorably with the MAD for the more costly G2(MP2), G2, and CBS-QCI/APNO models (1.6, 1.2, and 0.5 kcal/mol, respectively). The error distributions over the G2 test set are indistinguishable from Gaussian distribution functions for all six models, indicating that the rms errors can be interpreted in the same way that experimental uncertainties are used to assess reliability.However, a broader range of examples reveals special difficulties presented by spin contamination, high molecular symmetry, and localization problems in molecules with multiple lone pairs on the same atom. These characteristics can occasionally result in errors several times the size expected from the Gaussian distributions. Each of the CBS models has a range of molecular size for which it is the most accurate computational model currently available. The largest calculations reported for these models include: The CBS-4 heat of formation of tetranitrohydrazine (91.5±5 kcal/mol), the CBS-4 and CBS-q isomerization energies for the conversion of azulene to naphthalene (ΔHcalc=-35.2±1.0 kcal/mol, ΔHexp=-35.3±2.2 kcal/mol), and the CBS-Q heat of formation of SF6 (ΔHcalc=-286.6±1.3 kcal/mol, ΔHexp=-288.3±0.2 kcal/mol). The CBS-Q value for... [ABSTRACT FROM AUTHOR]

The major source of error in most ab initio calculations of molecular energies is the truncation of the one-electron basis set. An open-shell complete basis set (CBS) model chemistry, based on the unrestricted Hartree–Fock (UHF) zero-order wave function, is defined to include corrections for basis set truncation errors. The total correlation energy for the first-row atoms is calculated using the unrestricted Mo\ller–Plesset perturbation theory, the quadratic configuration interaction (QCI) method, and the CBS extrapolation. The correlation energies of the atoms He, Li, Be, B, C, N, O, F, and Ne, calculated using atomic pair natural orbital (APNO) basis sets, vary from 85.1% to 95.5% of the experimental correlation energies. However, extrapolation using the asymptotic convergence of the pair natural orbital expansions retrieves from 99.3% to 100.6% of the experimental correlation energies for these atoms. The total extrapolated energies (ESCF+Ecorrelation) are then in agreement with experiment to within ±0.0012 hartree (root-mean-square deviation) and represent the most accurate total energy calculations yet reported for the first-row atoms. [ABSTRACT FROM AUTHOR]

The major source of error in most ab initio calculations of molecular energies is the truncation of the one-electron basis set. A family of complete basis set (CBS) quadratic CI (QCI) model chemistries is defined to include corrections for basis set truncation errors. These models use basis sets ranging from the small 6-31 G°° double zeta plus polarization (DZ+P) size basis set to the very large (14s9p4d2f,6s3p1d)/[6s6p3d2f,4s2p1d] atomic pair natural orbital basis set. When the calculated energies are compared with the experimental energies of the first-row atoms and ions and the first-row diatomics and hydrides H2, LiH, Li2, CH4, NH3, H2O, HF, LiF, N2, CO, NO, O2, and F2, two very promising new model chemistries emerge. The first is of comparable accuracy, but more than ten times the speed of the G1 model of Pople and co-workers. The second is less than one-tenth the speed of the G1 model, but reduces the root-mean-square (rms) errors in ionization potentials (IPs), electron affinities (EAs), and D0’s to 0.033 and 0.013 eV, and 0.53 kcal/mol per bond, respectively. [ABSTRACT FROM AUTHOR]

The major source of errror in most ab initio calculations of molecular energies is the truncation of the one-electron basis set. A complete basis set model chemistry is defined to include corrections for basis set truncation errors. This model uses double zeta plus polarization level atomic pair natural orbital basis sets to calculate molecular self-consistent-field (SCF) energies and correlation energies. The small corrections to give the complete basis set SCF energies are then estimated using the l-6 asymptotic convergence of the multicenter angular momentum expansion. The calculated correlation energies of the atoms He, Be, and Ne, and of the hydrides LiH, BH3, CH4, NH3, H2O, and HF, using the double zeta plus polarization basis sets vary from 83.0% to 91.2% of the experimental correlation energies. However, extrapolation of each of the pair energies and pair-coupling terms to the complete basis set values using the asymptotic convergence of pair natural orbital expansions retrieves from 99.5±0.7% to 101.1±0.6% of the experimental correlation energies for these atoms and molecules. With the exception of ammonia which gave 101.1%, the calculated correlation energies agree with the experimental values to within the error limits of the experiments for all these atoms and molecules with more than four electrons. The total extrapolated energies (ESCF+ECorrelation) are then in agreement with experiment to within ±0.0014 hartree (root mean square deviation) and represent the most accurate total energy calculations yet reported for the molecules. The largest discrepancies with experiment occur for methane, where we obtain ETotal =-40.5112 hartree compared to EExpt =-40.514±0.002 hartree, and ammonia, where we obtain ETotal =-56.5659 hartree compared to EExpt =-56.563±0.002 hartree. [ABSTRACT FROM AUTHOR]

The second-order and total correlation energy of the water molecule are calculated with a basis set of 45 atomic pair natural orbitals. The asymptotic forms for the convergence of pair natural orbital expansions are then used to extrapolate to the values of the pair energies and pair-coupling terms that would be obtained with a complete basis set. The extrapolated complete basis set second-order correlation energy is equal to -361.1 mhartree and the extrapolated complete basis set total correlation energy is equal to -370.6 mhartree in agreement with the experimental value (-370±3 mhartree). The error in the extrapolated total correlation energy is more than an order-of-magnitude smaller than the error in any previous calculation. [ABSTRACT FROM AUTHOR]

Within the framework of many-body perturbation theory, the total correlation energy can be partitioned into: intraorbital pair energies, eii; interorbital pair energies, αβeij and ααeij; double-excitation pair-coupling terms eij,kl(D); and higher-excitation pair-coupling terms, eij,kl(S,T,Q,...). The asymptotic convergence of pair natural orbital expansions for each of these terms is determined for the model problem of n infinitely separated helium-like ions with infinite nuclear charge. For example, the asymptotic form of the basis set truncation error in an αβ-interorbital pair energy is LimitNij→∞Δαβeij =αβfij (Jμ=1Nij Cμij)2 ((-225/ 4608)) (Nij+δij)-1 , where Nij is the number of pair natural orbitals and Cμij is the coefficient of pair natural orbital configuration μij. Numerical studies of the neon atom verify that this model behavior applies to real many-electron systems. The pair-coupling terms beyond third-order contribute less than 1% of the total correlation energy in a variety of atoms and molecules and can therefore be neglected. As a practical test of the use of the asymptotic forms to extrapolate the remaining terms, a double zeta plus polarization set of pair natural orbitals was used. Extrapolation of each of the neon pair energies to the value for a complete basis set yields an independent electron pair approximation equal to -0.4233 hartree, which is 108.6% of the experimental correlation energy (-0.3896±0.001 hartree). Including the third-order MP-MBPT pair-coupling terms and extrapolating to a complete basis set gives a total correlation energy equal to -0.3904 hartree, which is 100.2±0.2% of the experimental value. A similarcalculation on H2O gave equally good results (calc. -0.3706; expt. -0.370±0.003 hartree) indicating that this DZ+P CBS method is applicable to polyatomic potential energy surfaces. [ABSTRACT FROM AUTHOR]

An improved complete basis set-quadratic configuration interaction/atomic pair natural orbital (CBS-QCI/APNO) model is described in this paper. It provides chemical energy differences (i.e., D0 I.P., and E.A.) with a mean absolute error of 0.53 kcal/mol for the 64 first-row examples from the G2 test set, and is computationally feasible for species with up to three first-row atoms. A set of 20 CBS-QCI/APNO bond dissociation energies of hydrocarbons also agree with known experimental values to within less than 1 kcal/mol. Calculations on the cyclopropenyl radical and cyclopropenylidene provide new dissociation energies which are in accord with an interpretation of the thermochemistry emphasizing ring strain and aromaticity. [ABSTRACT FROM AUTHOR]

Background: Research studies exploring the determinants of disease require sufficient statistical power to detect meaningful effects. Sample size is often increased through centralized pooling of disparately located datasets, though ethical, privacy and data ownership issues can often hamper this process. Methods that facilitate the sharing of research data that are sympathetic with these issues and which allow flexible and detailed statistical analyses are therefore in critical need. We have created a software platform for the Virtual Pooling and Analysis of Research data (ViPAR), which employs free and open source methods to provide researchers with a web-based platform to analyse datasets housed in disparate locations.Methods: Database federation permits controlled access to remotely located datasets from a central location. The Secure Shell protocol allows data to be securely exchanged between devices over an insecure network. ViPAR combines these free technologies into a solution that facilitates 'virtual pooling' where data can be temporarily pooled into computer memory and made available for analysis without the need for permanent central storage.Results: Within the ViPAR infrastructure, remote sites manage their own harmonized research dataset in a database hosted at their site, while a central server hosts the data federation component and a secure analysis portal. When an analysis is initiated, requested data are retrieved from each remote site and virtually pooled at the central site. The data are then analysed by statistical software and, on completion, results of the analysis are returned to the user and the virtually pooled data are removed from memory.Conclusions: ViPAR is a secure, flexible and powerful analysis platform built on open source technology that is currently in use by large international consortia, and is made publicly available at [http://bioinformatics.childhealthresearch.org.au/software/vipar/]. [ABSTRACT FROM AUTHOR]