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The R-matrix method is a fully-quantum time-independent scattering method, used to simulate nuclear, electron-atom, electron-ion, electron-molecule scattering and more. Here, a novel R-matrix method, RmatReact, is presented as applied to ultracold (sub-Kelvin) atom-atom scattering. This is in response to experimental methods which in recent decades have facilitated the routine use of ultracold atoms and small molecules in experiments. This project lays the groundwork for future codes to eventually simulate polyatom-polyatom reactive collisions. Results are presented in this paper for numerical comparisons to other established methods, and for resonances in the elastic scattering of ultracold argon atoms., Comment: 18 pages, 3 figures, 2 tables, EFB conference preceedings

A theoretical model for isotopologues of beryllium monohydride, BeH, BeD and BeT, A ${}^{2}{\rm{\Pi }}$ to X ${}^{2}{{\rm{\Sigma }}}^{+}$ visible and X ${}^{2}{{\rm{\Sigma }}}^{+}$ to X ${}^{2}{{\rm{\Sigma }}}^{+}$ infrared rovibronic spectra is presented. The MARVEL procedure is used to compute empirical rovibronic energy levels for BeH, BeD and BeT, using experimental transition data for the X ${}^{2}{{\rm{\Sigma }}}^{+}$, A ${}^{2}{\rm{\Pi }}$, and C ${}^{2}{{\rm{\Sigma }}}^{+}$ states. The energy levels from these calculations are then used in the program Duo to produce a potential energy curve for the ground state, X ${}^{2}{\rm{\Sigma }}$, and to fit an improved potential energy curve for the first excited state, A ${}^{2}{\rm{\Pi }}$, including a spin–orbit coupling term, a Λ-doubling state to state (A–X states) coupling term, and Born–Oppenheimer breakdown terms for both curves. These, along with a previously computed ab initio dipole curve for the X and A states are used to generate vibrational-rotational wavefunctions, transition energies and A-values. From the transition energies and Einstein coefficients, accurate assigned synthetic spectra for BeH and its isotopologues are obtained at given rotational and vibrational temperatures. The BeH spectrum is compared with a high resolution hollow-cathode lamp spectrum and the BeD spectrum with high resolution spectra from JET giving effective vibrational and rotational temperatures. Full A–X and X–X line lists are given for BeH, BeD and BeT and provided as supplementary data on the ExoMol website.

Alumni of a Council on Rehabilitation Education (CORE)–accredited graduate rehabilitation counselor education (RCE) program were surveyed to evaluate career outcomes, job satisfaction, licensure and certification rates, client populations served, and RCE program satisfaction and effectiveness. Results indicate a high level of satisfaction with the program and career outcomes and confirm the program’s effectiveness in meeting the education and career needs of its graduates. Information obtained provides valuable insight for other RCE programs that aspire to improve and grow to meet the needs of their students and the field.

CO2 and CO are listed as molecules 2 and 5, respectively, in the HITRAN database, with the former being the most important greenhouse gas in the Earth’s atmosphere and the latter being the second most common molecule in the Universe after H2. Thus knowing the line intensities of both CO2 and CO with low uncertainty has wideranging scientific importance. Until recently only the effective Hamiltonian and Dipole Moment Surfaces(DMS) were used to calculate line positions and intensities of these molecules. However, there is a theoretical line list based on variational calculations using a fitted potential energy surface (PES) and an ab initio DMS which has been determined recently1 and which givesCO2 line intensities that are accurate to within a few percent. In this work we attempt to improve and experimentally validate the accuracy of the predicted CO2 line intensities at the sub-percent level. However, only a few lines belonging to four CO2 bands have thus far been measured at this level of uncertainty. We performed ab initio calculations of the PES and DMS of CO2 at the all-electron MRCI level of theory using MOLPRO and an aug-cc-pcQz basis set. Values for about 2000 geometries were calculated with energies up to 20 000 cm−1 above the minimum. We fitted an analytical surface to these DMS points and calculated intensities using the excellent PES of Ref. 1 and our DMS using the variational triatomic nuclear motion program DVR3D2.We will present a comparison of our calculated line intensities with several measured lines in the four above-mentioned bands. This comparison between theory and experiments demonstrates that sub-percent relative uncertainty in the predicted intensities of CO2 lines has been achieved. The results of similarly accurate calculations on CO will also be presented.

Recommendations of an IUPAC Task Group, formed in 2011 on “Intensities and line shapes in high-resolution spectra of water isotopologues from experiment and theory”(Project No. 2011-022-2-100), on line profiles of isolated high-resolution rotational-vibrational transitions perturbed by neutral gas-phase molecules are presented. The well-documented inadequacies of the Voigt profile, used almost universally by databases and radiative-transfer codes to represent pressure effects and Doppler broadening in isolated vibrational-rotational and pure rotational transitions of the water molecule, have resulted in the development of a variety of alternative line profile models. These models capture more of the physics of the influence of pressure on line shapes but, in general, at the price of greater complexity. The Task Group recommends that the partially-Correlated quadratic-Speed-Dependent Hard-Collision profile should be adopted as the appropriate model for high-resolution spectroscopy. For simplicity this should be called the Hartmann–Tran profile (HTP). This profile is sophisticated enough to capture the various collisional contributions to the isolated line shape, can be computed in a straightforward and rapid manner, and reduces to simpler profiles, including the Voigt profile, under certain simplifying assumptions. For further details see: J. Tennyson et al, Pure Appl. Chem., 2014, in press.

High-temperature water linelists for three water isotopologues -H216O,H217O and H218O are calculated using the newly developed potential energy surfaces (PESs) and the high-quality dipole moment surface (DMS)1. ForH216O, a PES accurate up to 40 000 cm−1 was developed and the energy levels cutoff up to 40 000 cm−1 was used. The lines for all the levels up to J =72 are computed.The accuracy of the PES is an order of magnitude better than the one used for the BT2 linelist2.For the two minor isotopologues, less extensive linelists are calculated, which coincide in highest J ≤ 50 and energy levels up to 30 000 cm−1, with the parameters used for the BT2 linelist. A newly-developed method for calculating the PES of isotopologues is used which gives the same level of accuracy for H217O and H218O as obtained for known levels of H216O even when these levels are yet unknown experimentally for the minor isotopologue.

A dedicated mission to investigate exoplanetary atmospheres represents a major milestone in our quest to understand our place in the universe by placing our Solar System in context and by addressing the suitability of planets for the presence of life. EChO—the Exoplanet Characterisation Observatory—is a mission concept specifically geared for this purpose. EChO will provide simultaneous, multi-wavelength spectroscopic observations on a stable platform that will allow very long exposures. The use of passive cooling, few moving parts and well established technology gives a low-risk and potentially long-lived mission. EChO will build on observations by Hubble, Spitzer and ground-based telescopes, which discovered the first molecules and atoms in exoplanetary atmospheres. However, EChO’s configuration and specifications are designed to study a number of systems in a consistent manner that will eliminate the ambiguities affecting prior observations. EChO will simultaneously observe a broad enough spectral region—from the visible to the mid-infrared—to constrain from one single spectrum the temperature structure of the atmosphere, the abundances of the major carbon and oxygen bearing species, the expected photochemically-produced species and magnetospheric signatures. The spectral range and resolution are tailored to separate bands belonging to up to 30 molecules and retrieve the composition and temperature structure of planetary atmospheres. The target list for EChO includes planets ranging from Jupiter-sized with equilibrium temperatures T eq up to 2,000 K, to those of a few Earth masses, with T eq \u223c 300 K. The list will include planets with no Solar System analog, such as the recently discovered planets GJ1214b, whose density lies between that of terrestrial and gaseous planets, or the rocky-iron planet 55 Cnc e, with day-side temperature close to 3,000 K. As the number of detected exoplanets is growing rapidly each year, and the mass and radius of those detected steadily decreases, the target list will be constantly adjusted to include the most interesting systems. We have baselined a dispersive spectrograph design covering continuously the 0.4–16 μm spectral range in 6 channels (1 in the visible, 5 in the InfraRed), which allows the spectral resolution to be adapted from several tens to several hundreds, depending on the target brightness. The instrument will be mounted behind a 1.5 m class telescope, passively cooled to 50 K, with the instrument structure and optics passively cooled to \u223c45 K. EChO will be placed in a grand halo orbit around L2. This orbit, in combination with an optimised thermal shield design, provides a highly stable thermal environment and a high degree of visibility of the sky to observe repeatedly several tens of targets over the year. Both the baseline and alternative designs have been evaluated and no critical items with Technology Readiness Level (TRL) less than 4–5 have been identified. We have also undertaken a first-order cost and development plan analysis and find that EChO is easily compatible with the ESA M-class mission framework.

We present 'BYTe', a comprehensive 'hot' line list for the ro-vibrational transitions of ammonia, 14NH3, in its ground electronic state. This line list has been computed variationally using the program suite TROVE, a new spectroscopically-determined potential energy surface and an ab initio dipole moment surface. BYTe, is designed to be used at all temperatures up to 1500K. It comprises 1137650964 transitions in the frequency range from 0 to 12000 cm-1, constructed from 1366519 energy levels below 18000 cm-1 having J values below 36. Comparisons with laboratory data confirm the accuracy of the line list which is suitable for modelling a variety of astrophysical problems including the atmospheres of extrasolar planets and brown dwarfs., Comment: the paper has been submitted to MNRAS

The hot Jupiter HD 209458b was observed during primary transit at 3.6, 4.5, 5.8 and 8.0 microns using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We detail here the procedures we adopted to correct for the systematic trends present in the IRAC data. The light curves were fitted including limb darkening effects and fitted using Markov Chain Monte Carlo and prayer-bead Monte Carlo techniques, finding almost identical results. The final depth measurements obtained by a combined Markov Chain Monte Carlo fit are at 3.6 microns, 1.469 +- 0.013 % and 1.448 +- 0.013 %; at 4.5 microns, 1.478 +- 0.017 % ; at 5.8 microns, 1.549 +- 0.015 % and at 8.0 microns 1.535 +- 0.011 %. Our results clearly indicate the presence of water in the planetary atmosphere. Our broad band photometric measurements with IRAC prevent us from determining the additional presence of other other molecules such as CO, CO2 and methane for which spectroscopy is needed. While water vapour with a mixing ratio of 10^-4-10^-3 combined with thermal profiles retrieved from the day-side may provide a very good fit to our observations, this data set alone is unable to resolve completely the degeneracy between water abundance and atmospheric thermal profile., Comment: 14 pages, 6 tables, 10 figures, Accepted for publication in MNRAS

Journal URL: http://www.sciencedirect.com/science/journal/00092614

Journal URL: http://www.sciencedirect.com/science/journal/03010104

Journal URL: http://jcp.aip.org/jcp/staff.jsp

Journal URL: http://jcp.aip.org/jcp/staff.jsp

Ab initio electron scattering calculations are presented for methane, ethane and propane with particular emphasis on elastic cross sections. Calculations are performed with the Quantemol-N expert system which runs the UK polyatomic R-matrix code. These calculations are presented which systematically increase the size of the coupled states expansion which is used to represent polarisation effects in the scattering wave function. Agreement with experimental measurements is obtained provided sufficient coupled states are included in the expansion. Whether these coupled states expansions really converge the polarisation potential and the prospects for further calculations are discussed. (c) 2007 Elsevier B.V. All rights reserved.

We calculate cross sections for elastic scattering and electronic excitation of BF3 molecules by low energy electrons. The R-Matrix code Quantemol-N has been used for calculations. The cross sections indicate the presence of a shape resonance of symmetry B-1 (A(2)'' in D-3h) at around 4.5 eV.

Gray model atmospheres are generally considered a reasonable approximation to make upon stars of mass greater than about 0.6 M-circle dot. Here we show that non-gray atmospheres can significantly affect evolutionary models, with masses up to 0.9 M-circle dot. The effect of including a non-gray atmosphere is strongest in the pre-main and post-main Sequence. This may have implications for the ages of the oldest globular clusters.

State-of-the-art experiments and calculations are used to record and assign the data obtained in the weakly absorbing blue energy region of the H2O spectrum. Continuous-wave cavity ringdown absorption spectroscopy with Doppler resolution is used to probe the range from 25 195 to 25 470 cm(-1) with an absorption sensitivity of similar to 1 parts per 10(9) (ppb)/cm. 62 lines of the polyad nu(OH)=8 are reported, of which 43 are assigned using variational nuclear calculations. The study includes absorption line intensities (in the range of 10(-28)-10(-26) cm/molecule) for all lines and self-broadening pressure coefficient for a few lines. The newly obtained energy levels are also reported. (c) 2005 American Institute of Physics.

Line parameters for water vapour in natural abundance have recently been determined for the 9250-13 000 cm(-1) region [M.-F. Wrienne, A. Jenouvrier, C. Hermans, A.C. Vandaele, M. Carleer, C. Clerbaux, P.-F. Coheur, R. Colin, S. Fally, M. Bach, J. Quant. Spectrosc. Radiat. Transfer 82 (2003) 99] and the 13 000-26 000 cm(-1) region [P.-F. Coheur, S. Fally, M. Carleer, C. Clerbaux, R. Colin, A. Jenouvrier, M.-F. Wrienne, C. Hermans, A.C. Vandaele, J. Quant. Spectrosc. Radial. Transfer 74 (2002) 493] using a high-resolution Fourier-transform spectrometer with a long-path absorption cell. These spectra are analysed using several techniques including variational line lists and assignments made. In total, over 15 000 lines were assigned to transitions involving more than 150 exited vibrational states of (H2O)-O-16. Twelve new vibrational band origins are determined and estimates for a further 16 are presented. (c) 2005 Elsevier Inc. All rights reserved.

A long pathlength, Fourier transform spectrum of pure water vapour [J. Mol. Spectrose. 211 (2002) 169] has been fitted and analysed. Line centres, intensities, and self-broadening parameters have been obtained for about 3900 lines with intensities less then 1 X 10(-24) cm/molecule. Transitions to 240 newly observed energy levels of H2O have been identified. 855 lines have been assigned to three other major isotopologues of water. It is pointed out that a new intensity measurements are needed for the stronger lines in this region. (c) 2005 Elsevier Inc. All rights reserved.

This paper describes the status of the 2004 edition of the HITRAN molecular spectroscopic database. The HITRAN compilation consists of several components that serve as input for radiative transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e., spectra in which the individual lines are unresolvable; individual line parameters and absorption cross-sections for bands in the ultra-violet; refractive indices of aerosols; tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 39 molecules including many of their isotopologues.The format of the section of the database on individual line parameters of HITRAN has undergone the most extensive enhancement in almost two decades. It now lists the Einstein A-coefficients, statistical weights of the upper and lower levels of the transitions, a better system for the representation of quantum identifications, and enhanced referencing and uncertainty codes. In addition, there is a provision for making corrections to the broadening of line transitions due to line mixing. (C) 2005 Elsevier Ltd. All rights reserved.

A new procedure is presented for the ab initio study of electron-molecule collision at energies straddling the target ionization threshold. The R-matrix with pseudostates method, which allows for the inclusion of discretized continuum states in a close-coupling expansion, is adapted to molecular targets using even-tempered basis sets. Calculations for electron collisions with the H-3(+) molecular ion provide converged polarizabilities, electronic excitation and ionization cross sections.

Continuum states of the CO+ cation are studied as a function of internuclear distances in the range 1.7-3.0 a(0). R-matrix wavefunctions are constructed for 1Sigma(+), (2)Pi, (2)Delta and 4Pi total symmetries by study of collisions of electrons with a CO2+ target. Complex quantum defects are obtained from above threshold energy scattering calculations, yielding resonance energy curves and corresponding electronic couplings to the CO+ continuum. Results are presented and discussed for the high-n Feshbach resonances of the CO+ spectrum converging to excited states of CO2+. These curves are responsible for the recently observed dissociative recombination of Co2+.

Water is the single most important molecule for models of the earth's atmosphere but line parameters for water, particularly at shorter wavelengths, are difficult to measure reliably. We suggest that the most reliable way of generating water line parameters is to combine data obtained from a variety of sources, thereby separating line parameter determination into results for strong lines, for weak lines and for isotopically substituted water. Theoretical considerations which are addressed include line assignments and labeling of energy levels and the prospects of a full theoretical solution to the water vapor problem. Particular attention is paid to strong line absorption intensities in the near-infrared where recent studies have given significantly different results. The experimental data used to construct the ESA-WVR linelist (J. Mol. Spectrosc. 208 (2001) 32) is re-analyzed with a focus on effects due to pressure determination in the cell, subtraction of the baseline and parameterization of the line profiles. A preliminary re-analysis suggests that the line intensities given by the ESA-WVR study should be closer to those of Brown et al. (J. Mol. Spectrosc. 212 (2002) 57) used in the HITRAN. This shows the vital importance of validating the data for water by independent means. (C) 2003 Elsevier Ltd. All rights reserved.

We present a new ab initio HCN/HNC linelist. The linelist forms themost accurate and extensive HCN/HNC data set presently in existence.The data contain rotation vibration line frequencies and line strengths,for all transitions that are not rigorously dipole forbidden, between stateswith energy less than 18 000 cm-1 and with J ? 60.

Fourier transform spectra recorded using (a) natural abundance water vapor, (b) (H2O)-O-18-enriched water vapor, and (c) (H2O)-O-17-enriched water vapor are analyzed. The ratio of intensities in three spectra is used to identify 927 lines due to absorption by (H2O)-O-18. Intensities and self-broadening parameters are derived for these lines. Using theoretical linelists, comparisons with previously assigned (H2O)-O-16 spectra, and automatic searches for combination differences, 747 lines are assigned. These lines belong to 14 vibrational states in the 3nu + delta and 4nu polyads. Newly determined (H2O)-O-18 vibrational band origins include 4nu(1) at 13 793.09 cm(-1), 3nu(1) + nu(3) at 13 795.40 cm(-1), 2nu(1) + 2nu(3) at 14 188.82 cm(-1), nu(1) + 3nu(3) at 14 276.34 cm(-1), and 2nu(2) + 2nu(2) + nu(3) at 13 612.71 cm(-1). These results are compared with data in HITRAN. (C) 2002 Elsevier Science (USA).

Following our calculations of electron impact dissociation rates of molecular H-2, D-2 and T-2 (Trevisan and Tennyson 2002 Plasma Phys. Control. Fusion 44 1263-76), calculations for the mixed isotopomers HD, HT and DT have been made. Total cross sections and energy differential cross sections at threshold energies as a function of vibrational states (nu) for HD: nu = 0-5, for HT: nu = 0-5 and for DT: nu = 0-7 are calculated for the electron impact dissociation through excitation to the b(3)Sigma(u)(+) excited electronic state, which is the dominant dissociation process at such energies. The rates of dissociation as a function of electron temperature for each state are parametrized. Coinciding with our previous results, near-threshold rates are shown to be so critically dependent on the vibrational level that dissociation from very high-lying vibrational levels must be included in calculations of the rate at local thermal equilibrium (LTE) even at low temperature. Rates for the higher vibrational levels are obtained by extrapolation following the procedure discussed in our previous publication, and are then used to calculate the LTE rate. The LTE rate is an order of magnitude greater than the nu = 0 rate. A scaling law for the electron impact dissociation cross sections of vibrationally excited H-2 and its isotopomers has been derived.

Hegemonic discourses must by definition operate on several levels of the culture wherein they are active. This constant resignification of previously held symbols is not simply a matter of a top-down inscription of an interpretative schema onto any and all existing symbol systems in a society. Instead, the complicated dialogic nature of these processes must be recognized, thereby allowing the historian to catch hints of various subaltern or neglected voices and perspectives in the interstices of larger social discourses.1 Recognition of this fact allows the scholar to develop a necessary humility when the fragmented remains of entire world-views can only hint at how much has been irretrievably lost, as well as an appreciation for the activities of the ideologically or socially oppressed. The intricacies of the mundane, as opposed to the extraordinary, aspects of a specifically enculturated individual’s habitus have been amply demonstrated by Michel de Certeau’s The Practice of Everyday Life.2 It is with this work in particular that I would like to engage the reader’s attention when discussing the Mariological means by which individuals in Western Europe, and particularly northern France, dealt with the arrival of the first millennium.

Fourier transform emission spectra were recorded using a mixture of H2O and D2O at a temperature of 1500 degreesC. The spectra were recorded in three overlapping sections and cover the wavenumber range 380-2190 cm(-1). A total of 22106 lines were measured, of which 60% are thought to belong to HDO. A total of 6430 FIDO transition,, are assigned, including the first transitions to the (040) vibrational state, with a term value of 5420.042 cm(-1). A total of 1536 new energy levels of HDO belonging to the (000), (010) (020), (030), and (040) stated are presented, significantly extending the degree of rotational excitation compared to previous studies. (C) 2001 Elsevier Science.

A Fourier transform spectrum has been recorded of a H2O/D2O vapor mixture in the wavenumber range 16,300 to 22,800 cm(-1) using a long path cell. 410 lines of HDO are assigned to the OH stretching overtone bands 5 nu (3). 6 nu (3) and 7 nu (3) plus combination bands. Assignments for the 6 nu (3) and 7 nu (3) bands represent the first data for the 006 and 007 states and give band origins of 19.836.88 cm(-1) and 22,625.50 cm(-1), respectively. Rotational term values for these states are also obtained. (C) 2001 Academic Press.

1998

Contains fulltext : 75511.pdf (Publisher’s version ) (Open Access) 9 p.

Six cases of vertical root fractures accompanied by vertical bone loss are presented. Possible causes for these fractures are suggested. Four vertical fractures probably resulted from the use of excessive pressure at the time of obturation of the canals. One vertical root fracture may have been caused by the cementation of a post, and another may have been caused by the cementation of an inlay in an endodontically treated tooth. All of the fractures resulted in alveolar bone loss to the apical extent of the fracture lines. The definitive treatment in each case was extraction of the tooth or root amputation. In one case successful treatment was accomplished by apically positioning the flap.

Past and recent research on ethnic minorities with disabilities has indicated that they have identifiably unique characteristics and present special challenges to the rehabilitation counseling profession. Demographic data and research findings are presented which provide insight into how these characteristics and challenges impact the rehabilitation process. Recommendations are offered on how to enhance the professional preparation of rehabilitation counselors for improved services to ethnic minorities with disabilities.

This article reports results from a survey of registered workers' compensation rehabilitation providers in Florida on eight provider activities: (a) accurately representing themselves and their business interests to clients, (b) delivering testimony before workers' compensation judges that is accurate and unbiased, (c) accurately representing client capabilities and limitations to employers, (d) placing clients in positions not likely to result in reinjury, (e) delivering only services they are professionally qualified to deliver, (f) documenting any lack of client cooperation with rehabilitation services, (g) recommending retraining when necessary for successful placement, and (h) bi1llng only for services actually provided. Responses were analyzed for providers as a whole and also in relation to educational background, certification, and years of Florida workers' compensation rehabilitation experience. Results indicated that providers see aIl of the above as occurring with regularity, with documentation of lack of client cooperation receiving the 'highest rating for extent of occurrence and recommendation for retaining the lowest. Years of experience was not associated with differing perceptions, but providers with credentials in rehabilitation counseling rated some of the above activities as occurring with less frequency than providers without such background.

Contains fulltext : 7010.pdf (Publisher’s version ) (Open Access)

Five cases in which perforations of mandibular molars into the furca occurred during endodontic instrumentation of the canal are presented. This resulted in alveolar bone loss. All were relatively asymptomatic, which could present a problem in diagnosis of the periodontal defect. The prognosis is questionable. The only tooth retained was treated surgically by an apically positioned flap and opening of the furca area to make it accessible to cleansing. The best treatment is the avoidance of the perforation. This is accomplished by considering the configuration of the canals and the size of the reamer than can follow it. Overinstrumentation with an endodontic instrument that is too large in diameter should be avoided.

A draft set of rules of ethical conduct was sent to a stratified random sample (N = 600) from the American Rehabilitation Counseling Association and the National Rehabilitation Counseling Association memberships. Two-hundred and seventy-six (46%) useable responses were received. The primary foci of the study addressed: (a) the extent to which the 50 draft rules were relevant to the work of the rehabilitation counselor; and, (b) ways by which rehabilitation counselors typically respond to ethically relevant situations. Results of the findings are discussed; recommendations for practice and research are offered.

Cases involving vertical root fractures in endodontically treated teeth can present difficulties in diagnosis. There are clinical and radiographic signs that, when present, can make diagnosis easier. In the two cases presented here, displacement of portions of the root occurred long after obturation of the canal. This spreading apart or movement of the apical portions of the root could be a result of pressure from the proliferating chronic granulation tissue that was present. The radiographic finding of displacement of apical portions of the root can be an additional diagnostic sign that a vertical root fracture had occurred.

Thirty-two cases of vertical fractures were studied in an attempt to identify the causes and diagnostic signs normally present. In all of the patients except two, osseous defects were present and could be probed. The majortiy (65.63 percent) had only mild pain or a dull discomfort. Seventy-five percent showed diffuse widening of the periodontal ligament space. This study suggests that excessive force during lateral condensation of the gutta-percha caused 84.38 percent of the fractures. A secondary cause was the forcing or tapping of inlays or dowels into place. The majority (78.13 percent) of the patients were over the age of 40. In all but nine of the cases, treatment consisted of the extraction of the involved teeth.

Fifteen hundred permanent teeth were examined for mesiodistal widths of roots at the cervical, middle third, and apical third areas of the root. One hundred twenty-five teeth of each unit of the dentition, except second and third molars, were observed. These observations were recorded, and the means, standard deviations, 95% confidence intervals, and ranges were calculated. By use of the confidence interval, the optimal dowel size was selected.

Contains fulltext : 6997.pdf (Publisher’s version ) (Open Access)

Quantum beat spectroscopy is combined with triple-resonance vibrational overtone excitation to measure the Stark coefficients (SCs) of the water molecule for 28 rovibrational levels lying from 27 600 to 41 000 cm−1. These data provide a stringent test for assessing the accuracy of the available potential energy surfaces (PESs) and dipole moment surfaces (DMSs) of this benchmark molecule in this energy region, which is inaccessible by direct absorption. SCs, calculated using the combination of a high accuracy, spectroscopically determined PES and a recent ab initio DMS, are within the 1% accuracy of available experimental data for levels below 25 000 cm−1 , and within 4.5% for coefficients associated with levels up to 35000 cm−1. However, the error in the computed coefficients is over 60% for the very high rovibrational states lying just below the lowest dissociation threshold, due, it seems, to lack of a high accuracy PES in this region. The comparative analysis sug-gests further steps, which may bring the theoretical predictions closer to the experimental accuracy.

A theoretical model for isotopologues of beryllium monohydride, BeH, BeD and BeT, A (2)Pi to X (2)Sigma(+) visible and X (2)Sigma(+) to X (2)Sigma(+) infrared rovibronic spectra is presented. The MARVEL procedure is used to compute empirical rovibronic energy levels for BeH, BeD and BeT, using experimental transition data for the X (2)Sigma(+), A (2)Pi, and C (2)Sigma(+) states. The energy levels from these calculations are then used in the program Duo to produce a potential energy curve for the ground state, X (2)Sigma, and to fit an improved potential energy curve for the first excited state, A (2)Pi, including a spin-orbit coupling term, a A-doubling state to state (A-X states) coupling term, and Born-Oppenheimer breakdown terms for both curves. These, along with a previously computed ab initio dipole curve for the X and A states are used to generate vibrational-rotational wavefunctions, transition energies and A-values. From the transition energies and Einstein coefficients, accurate assigned synthetic spectra for BeH and its isotopologues are obtained at given rotational and vibrational temperatures. The BeH spectrum is compared with a high resolution hollow-cathode lamp spectrum and the BeD spectrum with high resolution spectra from JET giving effective vibrational and rotational temperatures. Full A-X and X-X line lists are given for BeH, BeD and BeT and provided as supplementary data on the ExoMol website.