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Registries are gaining importance both in clinical practice and for research purposes. However, quality control is paramount to ensure that data are consistent and reliable. Quality control protocols have been proposed for arthroplasty registries, but these are not directly applicable to the spine setting. This study aims to develop a new quality control protocol for spine registries. Based on the available protocols for arthroplasty registries, a new protocol for spine registries was developed. The items included in the protocol were completeness (yearly enrollment rate and rate of assessment completion), consistency, and internal validity (coherence between registry data and medical records for blood loss, body mass index, and treated levels). All aspects were then applied to the spine registry of the Institution to verify its quality for each of the 5 years in which the registry has been used (2016-2020). Regarding completeness, the yearly enrollment rate ranged from 78 to 86%; the completion of preoperative assessment from 79% to 100%. The yearly consistency rate varied from 83% to 86%. Considering internal validity, the interclass correlation coefficient ranged from 0.1 to 0.8 for blood loss and from 0.3 to 0.9 for body mass index. The coherency for treated levels ranged from 25% to 82%. Overall, all 3 items showed an improvement over time. All 3 analyzed domains showed good to excellent results. The overall quality of the registered data improved over time. [ABSTRACT FROM AUTHOR]

Vibrational resonances for H3+ and D2H+, as well as H3+ at J=3, are calculated using a complex absorbing potential (CAP) method with an automated procedure to find stability points in the complex plane. Two different CAP functional forms and different CAP extents are used to analyze the consistency of the results. Calculations are performed using discrete variable representation continuum basis elements calculated to high levels of accuracy by diagonalizing large, dense, Hamiltonian matrices. For D2H+, two energy regions are analyzed: the one where D2+H+ is the only dissociation product and the one where HD+D+ can also be formed. Branching ratios are obtained in the latter case by using different CAPs. It is shown that H3+ and D2H+ support some narrow Feshbach-type resonances but that higher angular momentum states must be studied to model the pre-dissociation spectrum recorded by Carrington and co-workers [J. Chem. Phys. 98, 1073 (1993)]. [ABSTRACT FROM AUTHOR]

Vibrational resonances for H3+ and D2H+, as well as H3+ at J=3, are calculated using a complex absorbing potential (CAP) method with an automated procedure to find stability points in the complex plane. Two different CAP functional forms and different CAP extents are used to analyze the consistency of the results. Calculations are performed using discrete variable representation continuum basis elements calculated to high levels of accuracy by diagonalizing large, dense, Hamiltonian matrices. For D2H+, two energy regions are analyzed: the one where D2+H+ is the only dissociation product and the one where HD+D+ can also be formed. Branching ratios are obtained in the latter case by using different CAPs. It is shown that H3+ and D2H+ support some narrow Feshbach-type resonances but that higher angular momentum states must be studied to model the pre-dissociation spectrum recorded by Carrington and co-workers [J. Chem. Phys. 98, 1073 (1993)]. [ABSTRACT FROM AUTHOR]

The high accuracy ab initio adiabatic potential energy surfaces (PESs) of the ground electronic state of the water molecule, determined originally by Polyansky et al. [Science 299, 539 (2003)] and called CVRQD, are extended and carefully characterized and analyzed. The CVRQD potential energy surfaces are obtained from extrapolation to the complete basis set of nearly full configuration interaction valence-only electronic structure computations, augmented by core, relativistic, quantum electrodynamics, and diagonal Born-Oppenheimer corrections. We also report ab initio calculations of several quantities characterizing the CVRQD PESs, including equilibrium and vibrationally averaged (0 K) structures, harmonic and anharmonic force fields, harmonic vibrational frequencies, vibrational fundamentals, and zero-point energies. They can be considered as the best ab initio estimates of these quantities available today. Results of first-principles computations on the rovibrational energy levels of several isotopologues of the water molecule are also presented, based on the CVRQD PESs and the use of variational nuclear motion calculations employing an exact kinetic energy operator given in orthogonal internal coordinates. The variational nuclear motion calculations also include a simplified treatment of nonadiabatic effects. This sophisticated procedure to compute rovibrational energy levels reproduces all the known rovibrational levels of the water isotopologues considered, H216O, H217O, H218O, and D216O, to better than 1 cm-1 on average. Finally, prospects for further improvement of the ground-state adiabatic ab initio PESs of water are discussed. [ABSTRACT FROM AUTHOR]

A potential energy surface for the major isotopomer of water is constructed by fitting to observed vibration-rotation energy levels of the system using the exact kinetic energy operator nuclear motion program DVR3D. The starting point for the fit is the ab initio Born-Oppenheimer surface of Partridge and Schwenke [J. Chem. Phys. 106, 4618 (1997)] and corrections to it: both one- and two-electron relativistic effects, a correction to the height of the barrier to linearity, allowance for the Lamb shift and the inclusion of both adiabatic and nonadiabatic non-Born-Oppenheimer corrections. Fits are made by scaling the starting potential by a morphing function, the parameters of which are optimized. Two fitted potentials are presented which only differ significantly in their treatment of rotational nonadiabatic effects. Energy levels up to 25 468 cm[SUP-1] with J=0, 2, and 5 are fitted with only 20 parameters. The resulting potentials predict experimentally known levels with J⩽10 with a standard deviation of 0.1 cm[SUP-1], and are only slightly worse for J520, for which rotational nonadiabatic effects are significant. The fits showed that around 100 known energy levels are probably the result of misassignments. Analysis of misassigned levels above 20 000 cm[SUP-1] leads to the reassignment of 23 transitions. [ABSTRACT FROM AUTHOR]

Extensive calculations for the vibrational band origins of D 2 H + up to dissociation are presented. Due to the high density of vibrational states near dissociation, huge basis sets needed to be used as well as massively parallel computers. We have found 1209 A 1 and 1078 B 1 bound states, some of which display long-range features, which are analysed in detail. The calculations were performed within the Born–Oppenheimer approximation and non-adiabatic corrections to it are evaluated. However, the main source of error for the states near dissociation arises from the Potential Energy Surface at high energies. [ABSTRACT FROM AUTHOR]

Relativistic corrections beyond the simple one-electron mass–velocity–Darwin (MVD1) approximation to the ground-state electronic energy of H2S are determined at over 250 geometries. The corrections considered include the two-electron Darwin, the Gaunt and Breit corrections, and the one-electron Lamb shift. Fitted correction surfaces are constructed and used with an accurate ab initio nonrelativistic Born–Oppenheimer potential, determined previously (J. Chem. Phys. 115 (2001) 1229), to calculate vibrational and rotational levels for H232S. The calculations suggest that one- and two-electron relativistic corrections have a noticable influence on the levels of H2S. As for water, the effects considered have markedly different characteristics for the stretching and bending states. [Copyright &y& Elsevier]

Purpose: Identifying perioperative factors that may influence the outcomes of long spine fusion for the treatment of adult deformity is key for tailored surgical planning and targeted informed consent. The aim of this study was to analyze the association between demographic or perioperative factors and clinical outcomes 2 years after long spine fusion for the treatment of adult deformity. Methods: This study is a multivariate analysis of retrospectively collected data. All patients who underwent long fusion of the lumbar spine for adult spinal deformity (January 2016–June 2019) were included. The outcomes of interest were the Oswestry disability index (ODI), visual analogic scale (VAS) preoperatively and at 1 and 2 years' follow up, age, body mass index, American Society of Anaesthesiologists (ASA) score, upper and lowest instrumented vertebrae (UIV and LIV, respectively), length of surgery, estimated blood loss, and length of hospital stay. Results: Data from 192 patients were available. The ODI at 2 years correlated weakly to moderately with age (r = 0.4), BMI (r = 0.2), ASA (r = 0.3), and LIV (r = 0.2), and strongly with preoperative ODI (r = 0.6). The leg VAS at 2 years moderately correlated with age (r = 0.3) and BMI (r = 0.3). Conclusion: ODI and VAS at 2 years' follow-up had no to little association to preoperative age, health status, LIV, or other peroperative data, but showed a strong correlation with preoperative ODI and pain level. [ABSTRACT FROM AUTHOR]