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The lowest electronically excited states of Na2 are of interest as intermediaries in the excitation of higher states and in the development of methods for producing cold molecules. We have compiled previously obtained spectroscopic data on the A 1Σu+ and b 3Πu states of Na2 from about 20 sources, both published and unpublished, together with new sub-Doppler linewidth measurements of about 15 000 A←X transitions using polarization spectroscopy. We also present new ab initio results for the diagonal and off-diagonal spin-orbit functions. The discrete variable representation is used in conjunction with Hund’s case a potentials plus spin-orbit effects to model data extending from v=0 to very close to the 3 2S+3 2P1/2 limit. Empirical estimates of the spin-orbit functions agree well with the ab initio functions for the accessible values of R. The potential function for the A state includes an exchange potential for S+P atoms, with a fitted coefficient somewhat larger than the predicted value. Observed and calculated term values are presented in an auxiliary (EPAPS) file as a database for future studies on Na2. [ABSTRACT FROM AUTHOR]

Collisional energy transfer from H atoms to CO(v=0, J[bar_over_tilde:_approx._equal_to]2) has been studied at a collision energy of 1.58±0.07 eV by photolyzing H2S at 222 nm in a nozzle expansion with CO and probing the CO(v‘, J‘) levels using tunable VUV laser-induced fluorescence. The ratio CO(v‘=1)/CO(v‘=0) is found to be 0.1±0.008. The rotational distribution of CO(v‘=0) peaks at J‘≤11 and decays gradually; population is still observed at J‘≥45. The rotational distribution of CO(v‘=1) is broad and peaks near J‘=20. The experimental results are compared to quasiclassical trajectory calculations performed both on the H+CO surface of Bowman, Bittman, and Harding (BBH) and on the surface of Murrell and Rodriguez (MR). The experimental rotational distributions, particularly those for CO(v‘=1), show that the BBH surface is a better model than the MR surface. The most significant difference between the two surfaces appears to be that for energetically accessible regions of configuration space the derivative of the potential with respect to the CO distance is appreciable only in the HCO valley for the BBH surface, but is large for all H atom approaches in the MR potential. Because the H–CO geometry is bent in this valley, vibrational excitation on the BBH surface is accompanied by appreciable rotational excitation, as observed experimentally. [ABSTRACT FROM AUTHOR]

The dissociation of carbon suboxide by single photon absorption at 157.6 nm has been studied under the collisionless environment of a molecular beam. The primary products are 2CO+C [3P(97%) or 1D(3%) ]. The spin–orbit levels of the 3P carbon are statistically distributed. The CO rotational populations in the first four vibrational levels are found to be well described by Boltzmann distributions with temperatures 3430, 4120, 4670, and 2340 K for υ=0,1,2,3, respectively. A second low temperature component in the υ=0 rotational distribution is attributed to CO produced in coincidence with C(1D). Significant population is found in the first four vibrational levels with less than 3% estimated in the higher levels; a vibrational temperature of 3700 K fits the distribution. Analysis of the Doppler profiles of the CO and carbon suggest that the dissociation is stepwise; the first dissociation appears to be described by an anisotropy parameter near β=2, while the second appears to be isotropic. The mean CO fragment speeds were nearly constant for all rotational levels, though slightly faster for υ=1 than υ=0. From the translational energetics of the CO at least a small amount of stable C2O is inferred to exist. The overall energetics place the stable C2O quantum yield under 2% assuming that excited C2O is not radiatively stabilized. We were unable to detect C2O directly in any electronic state. The dissociation of C3O2 into C(3P)+2CO appears to be best described as a stepwise reaction that produces a nearly statistical partitioning into all fragment degrees of freedom. The best agreement is obtained for an intermediate C2O electronic state in the vicinity of the b state (e.g., b, a or A); a ground state C2O intermediate is unlikely. The singlet to triplet crossing most likely occurs in the C2O system on a time scale longer than a rotation (a few picoseconds). [ABSTRACT FROM AUTHOR]

The photodissociation of glyoxal has been investigated by monitoring the CO internal energy distribution using tunable vacuum ultraviolet laser-induced fluorescence on the A←X system. Appearance times for the CO are in excellent agreement with the glyoxal fluorescence decay times, indicating that there is no long-lived intermediate in the dissociation. The quantum yield for CO production is independent of the K quantum number describing the glyoxal rotation. The CO is formed almost entirely in v=0 but is spread over a broadly excited rotational distribution peaking at J[bar_over_tilde:_approx._equal_to]42. Analysis of the CO Doppler profiles shows that the velocity of the CO increases with increasing rotational level and that the CO recoil velocity vector is oriented predominantly perpendicular to its angular momentum vector. These observations, which are in agreement with both previous time-of-flight data and molecular orbital calculations, are consistent with a model for the dissociation involving planar intermediates for the two channels leading to CO+H2CO or to 2 CO+H2. It appears that the highest rotational levels of CO are produced in coincidence with the H2CO channel. [ABSTRACT FROM AUTHOR]

Introduction: India faces lot of neonatal morbidity. Non-invasive blood pressure (NIBP) monitoring is being used for monitoring sick new borns as a safe and cost effective method of blood pressure monitoring. But there is no available information on normal values of NIBP for neonates in India. With more stress of government (and advancement) in new born care, establishing normative data of NIBP in Indian newborns should be high priority. Material and Methods: This was an observational cohort study done in a level III neonatal intensive care unit. 164 clinically stable babies on day 1 of life were included. Blood pressure was measured by the Oscillometric method. Results: Progressive increase of blood pressure was seen with increasing birth weight. 10th, 50th, 75th, 95th Centile curves were drawn from available data. For very low birth weight babies (< 1500grams), the values of systolic, diastolic and mean BP (±2standard deviations (S.D.)) were found to be 53.7 + 1.7, 29.1 + 1.7 and 41 + 1.1 mm Hg respectively. For low birth weight babies, i.e. with birth weight 1500-2499 grams, the values for systolic, diastolic and mean BP(±2 S.D.) were 62.2 + 2.5, 34.8 + 2.4 and 46.6 + 2.4 mm Hg respectively. For normal weight babies (more than 2499 grams), the systolic, diastolic and mean BP (±2 S.D.) were 72.8 + 4.2, 43 + 4 and 55.3+ 4 mm Hg respectively. The rise in systolic blood pressure with rising birth weight was highly significant (p <0.001). Similar were the results for diastolic and mean BPs, (p<0.001 for both), Conclusion: Blood pressure on day 1 of life appears to be directly related to birth weight. The effect is seen in all (i.e. systolic, diastolic and mean) blood pressure values. [ABSTRACT FROM AUTHOR]

The clinical characteristics and the retinal breaks associated with rhegmatogenous retinal detachments secondary to accidental globe perforation during local infiltration anaesthesia in five highly myopic eyes are presented. Retinal detachment was total with variable proliferative vitreoretinopathy. The pattern of retinal breaks was rather typical and predictable. Management involved vitreous surgery with internal tamponade by silicone oil in four eyes and perfluoropropane gas in one eye. At the last follow-up, all eyes had attached retina. One eye did not recover useful vision due to possible concurrent optic nerve damage.

The lowest electronically excited states of Na2 are of interest as intermediaries in the excitation of higher states and in the development of methods for producing cold molecules. We have compiled previously obtained spectroscopic data on the A 1Σu+ and b 3Πu states of Na2 from about 20 sources, both published and unpublished, together with new sub-Doppler linewidth measurements of about 15 000 A←X transitions using polarization spectroscopy. We also present new ab initio results for the diagonal and off-diagonal spin-orbit functions. The discrete variable representation is used in conjunction with Hund’s case a potentials plus spin-orbit effects to model data extending from v=0 to very close to the 3 2S+3 2P1/2 limit. Empirical estimates of the spin-orbit functions agree well with the ab initio functions for the accessible values of R. The potential function for the A state includes an exchange potential for S+P atoms, with a fitted coefficient somewhat larger than the predicted value. Observed and calculated term values are presented in an auxiliary (EPAPS) file as a database for future studies on Na2. [ABSTRACT FROM AUTHOR]