Isotope Spectroscopy

The measurement of isotopic ratios provides a privileged insight both into nucleosynthesis and into the mechanisms operating in stellar envelopes, such as gravitational settling. In this article, we give a few examples of how isotopic ratios can be determined from high-resolution, high-quality stellar spectra. We consider examples of the lightest elements, H and He, for which the isotopic shifts are very large and easily measurable, and examples of heavier elements for which the determination of isotopic ratios is more difficult. The presence of 6Li in the stellar atmospheres causes a subtle extra depression in the red wing of the 7Li 670.7 nm doublet which can only be detected in spectra of the highest quality. But even with the best spectra, the derived $^6$Li abundance can only be as good as the synthetic spectra used for their interpretation. It is now known that 3D non-LTE modelling of the lithium spectral line profiles is necessary to account properly for the intrinsic line asymmetry, which is produced by convective flows in the atmospheres of cool stars, and can mimic the presence of 6Li. We also discuss briefly the case of the carbon isotopic ratio in metal-poor stars, and provide a new determination of the nickel isotopic ratios in the solar atmosphere.Comment: AIP Thinkshop 10 "High resolution optical spectroscopy", invited talk, AN in pres

third caesarean section in patient with myasthenia gravis

Abstract Myasthenia gravis (MG) is an autoimmune neuromuscular disease, characterised by muscle weakness and fatigability of the voluntary muscles, it affects young women in the second and third decade of life. We report a case of 30 years old multigravida woman with myasthenia gravis submitted to third iterative caesarean section with no adverse neonatal and maternal outcome. The course myathenia is highly variable and unpredictable during gestation and can change in subsequent pregnancies. Delivery specially, through caesarean section is very stressful and may cause severe myasthenic crisis. Although pregnancy and delivery represent particular events, that require more attention in these patients, they are not associated, in most cases, with higher risks of complications compared to normal pregnancy, delivery and postpartum period. According our experiences, in the management of myasthenic pregnant woman is necessary cooperation in a multidisciplinary team between obstetricians, neurologist, anaesthetist, and neonatologist for ensure an optimum outcome

Curiouser and curiouser: The peculiar chemical composition of the Li: The Na-rich star in ω Centauri

We present a multi-instrument spectroscopic analysis of the unique Li- and Na-rich giant star #25664 in ω Centauri, using spectra acquired with FLAMES-GIRAFFE, X-shooter, UVES, and HARPS. Li and Na abundances have been derived from the UVES spectrum using transitions weakly sensitive to non-local thermodynamic equilibrium and assumed isotopic ratios. This new analysis confirms the surprising Li and Na abundances of this star (A(Li)NLTE = +2.71 ± 0.07 dex, [Na/Fe]NLTE = +1.00 ± 0.05 dex). Additionally, we provide new pieces of evidence for its chemical characterisation. The 12C13C isotopic ratio (15 ± 2) shows that this star has not yet undergone the extra-mixing episode usually associated with the red giant branch bump. Therefore, we can rule out the scenario of efficient deep extra mixing during the red giant branch phase envisaged to explain the high Li and Na abundances. Also, the star exhibits high abundances of both C and N ([C/Fe] = +0.45 ± 0.16 dex and [N/Fe] = +0.99 ± 0.20 dex), which is not compatible with the typical C-N anti-correlation observed in globular cluster stars. We found evidence of a radial velocity variability in #25664, suggesting that the star could be part of a binary system, likely having accreted material from a more massive companion when the latter was evolving in the asymptotic giant branch (AGB) phase. Viable candidates for the donor star are AGB stars with 3-4 M⊙ and super-AGB stars (~7-8 M⊙), both of which are able to produce Li- and Na-rich material. Alternatively, the star could have formed from the pure ejecta of a super-AGB star before the dilution with primordial gas occurred

Role of the mucins in pathogenesis of COPD: implications for therapy.

Introduction: Evidence accumulated in the last decade has started to reveal the enormous complexity in the expression, interactions and functions of the large number of different mucins present in the different compartments of the human lower airways. This occurs both in normal subjects and in COPD patients in different clinical phases and stages of severity.Areas covered: We review the known physiological mechanisms that regulate mucin production in human lower airways of normal subjects, the changes in mucin synthesis/secretion in COPD patients and the clinical efficacy of drugs that modulate mucin synthesis/secretion.Expert opinion: It is evident that the old simplistic concept that mucus hypersecretion in COPD patients is associated with negative clinical outcomes is not valid and that the therapeutic potential of 'mucolytic drugs' is under-appreciated due to the complexity of the associated molecular network(s). Likewise, our current knowledge of the effects of the drugs already available on the market that target mucin synthesis/secretion/structure in the lower airways is extremely limited and often indirect and more well-controlled clinical trials are needed in this area

Curiouser and curiouser: The peculiar chemical composition of the Li: The Na-rich star in ω Centauri

We present a multi-instrument spectroscopic analysis of the unique Li- and Na-rich giant star #25664 in ω Centauri, using spectra acquired with FLAMES-GIRAFFE, X-shooter, UVES, and HARPS. Li and Na abundances have been derived from the UVES spectrum using transitions weakly sensitive to non-local thermodynamic equilibrium and assumed isotopic ratios. This new analysis confirms the surprising Li and Na abundances of this star (A(Li)NLTE = +2.71 ± 0.07 dex, [Na/Fe]NLTE = +1.00 ± 0.05 dex). Additionally, we provide new pieces of evidence for its chemical characterisation. The 12C13C isotopic ratio (15 ± 2) shows that this star has not yet undergone the extra-mixing episode usually associated with the red giant branch bump. Therefore, we can rule out the scenario of efficient deep extra mixing during the red giant branch phase envisaged to explain the high Li and Na abundances. Also, the star exhibits high abundances of both C and N ([C/Fe] = +0.45 ± 0.16 dex and [N/Fe] = +0.99 ± 0.20 dex), which is not compatible with the typical C-N anti-correlation observed in globular cluster stars. We found evidence of a radial velocity variability in #25664, suggesting that the star could be part of a binary system, likely having accreted material from a more massive companion when the latter was evolving in the asymptotic giant branch (AGB) phase. Viable candidates for the donor star are AGB stars with 3-4 M⊙ and super-AGB stars (~7-8 M⊙), both of which are able to produce Li- and Na-rich material. Alternatively, the star could have formed from the pure ejecta of a super-AGB star before the dilution with primordial gas occurred

Initial State Dependence of the Breakup of Weakly Bound Carbon Isotopes

The one-neutron nuclear breakup from the Carbon isotopes $^{19}$C and $^{17}$C, is calculated as an example of application of the theory of transfer to the continuum reactions in the formulation which includes spin coupling. The effect of the energy sharing between the parallel and transverse neutron momentum distributions is taken into account thus resulting in a theory which is more general than sudden eikonal approaches. Both effects are necessary to understand properly the breakup from not too weakly bound $l_i>1$ orbitals. Breakup which leaves the core into an excited state below particle threshold is also considered. The core-target interaction is treated in the smooth cut-off approximation. By comparing to presently available experimental data we show how to make some hypothesis on the quantum numbers and occupancy of the neutron initial state. Possible ambiguities in the interpretation of inclusive cross sections are discussed.Comment: 22 RevTeX pages,3 ps figures. Phys. Rev. C, accepte

Discordance between patient and physician global assessment of disease activity in Behçet's syndrome: a multicenter study cohort

Background: To compare the patients' and physician's global assessment of disease activity in Behçet's syndrome (BS) and investigate the frequency, magnitude, and determinants of potential discordance. Methods: A total of 226 adult BS patients with a median (IQR) age of 46.9 (35.6-55.2) years were enrolled across Italy, Greece, Portugal, and Spain. Demographic, clinical, and therapeutic variables, as well as the patient reported outcomes, were collected at the recruitment visit. The physical (PCS) and mental (MCS) component summary scores of the Short Form Questionnaire 36 (SF-36) and the Behçet's syndrome Overall Damage Index (BODI) were calculated. Disease activity was assessed by the patients' (PtGA) and physician's global assessment (PGA) in a 10-cm visual analog scale, as well as the Behçet Disease Current Activity Form (BDCAF). Discordance (∆) was calculated by subtracting the PGA from the PtGA and defined as positive (PtGA>PGA) and negative (PtGA 80%) of disagreements were due to patients rating higher their disease activity. Higher values of BDCAF were associated to increased rate of positive discordance. When BDCAF = 0, the median (IQR) values of PtGA and PGA were 0.2 (0-2) and 0 (0-1), respectively. PCS (adjusted odds ratio (adjOR) 0.96 per unit, 95% CI 0.93-0.98, p = 0.006) and MCS (adjOR 0.96 per unit, 95% CI 0.93-0.99, p = 0.003) were independently associated with positive discordance using both cutoffs. Active ocular involvement emerged as a potential determinant of negative discordance (adjOR 5.88, 95% CI 1.48-23.30, p = 0.012). Conclusions: PtGA and PGA should be considered as complementary measures in BS, as patients and physicians may be influenced by different factors when assessing active disease manifestations. Particularly, PtGA may be a useful tool in the assessment of BS disease activity, as it carries a low risk to misclassify an inactive disease, and may allow to capture aspects of the patient's health that negatively affect his well-being and the treatment

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum