Laser spectroscopy of CaNC and SrNC

Low-resolution laser excitation and dispersed laser-induced fluorescence spectra of CaNC and SrNC were recorded. The laser excitation spectra ofthe B 'X+-z *E* and x 'D-g 2E+ transitions of SrNC are consistent with a linear, isocyanide structure. For both CaNC and SrNC, additional strong, non-resonant features occur to the red of the B 'X+-R 'E+ and A *H-g 'Z' transitions in the dispersed fluorescence spectra. Although these features remain unassigned, they might be due to emission from the isomerit, linear cyanides, CaCN and SrCN. In this case, the excited state potential curves need to have a small barrier between tbe cyanide and the isocyanide forms

All-fiber tunable optical delay line

We present a tunable optical delay line based on the use of a single chirped fiber Bragg grating written into a standard single mode optical fiber. In the proposed scheme, the delay is induced through the Bragg grating differential group delay curve. This is achieved by launching orthogonally polarized optical pulses in both directions into the Bragg grating and by controlling its local birefringence. This bidirectional propagation allows to compensate the second-order dispersion. The setup is suitable to delay pulses with a spectral width just less than the grating reflection bandwidth, which is particularly useful in the context of forthcoming wavelength division multiplexing ultra-high bit rate lightwave systems. In this work, the performances of the setup are investigated using a pulsed laser delivering 6.3 ps Fourier transform limited pulses at 1548 nm. A maximum delay of 120 ps (about 20 times the pulse width) is reported experimentally

Correlation between multiple modulation instability side lobes in dispersion oscillating fiber

We investigate numerically and experimentally the spectral correlation between multiple modulation instability (MI) side lobes in a dispersion oscillating fiber. By leveraging the dispersive Fourier transformation, we acquire instantaneous spectra and investigate the energy correlation between individual MI sidebands through scattergrams. We found that conjugate MI side lobes are strongly correlated while other combinations experience a very low degree of correlation, revealing that parametric processes related to each side lobe pair act quasi-independently.published_or_final_versio

Centrosymmetric molecules as possible carriers of diffuse interstellar bands

In this paper, we present new data with interstellar C2 (Phillips bands A-X), from observations made with the Ultraviolet-Visual Echelle Spectrograph of the European Southern Observatory. We have determined the interstellar column densities and excitation temperatures of C2 for nine Galactic lines. For seven of these, C2 has never been observed before, so in this case the still small sample of interstellar clouds (26 lines of sight), where a detailed analysis of C2 excitation has been made, has increased significantly. This paper is a continuation of previous works where interstellar molecules (C2 and diffuse interstellar bands) have been analysed. Because the sample of interstellar clouds with C2 has increased, we can show that the width and shape of the profiles of some diffuse interstellar bands (6196 and 5797 A) apparently depend on the gas kinetic and rotational temperatures of C2; the profiles are broader because of the higher values of the gas kinetic and rotational temperatures of C2. There are also diffuse interstellar bands (4964 and 5850 A) for which this effect does not exist.Comment: 8 pages, 4 figures, accepted to MNRAS 201

Abundances and rotational temperatures of the C2 interstellar molecule towards six reddened early-type stars

Using high-resolution (~85000) and high signal-to-noise ratio (~200) optical spectra acquired with the European Southern Observatory Ultraviolet and Visual Echelle Spectrograph, we have determined the interstellar column densities of C2 for six Galactic lines of sight with E(B- V) ranging from 0.33 to 1.03. For our purposes, we identified and measured absorption lines belonging to the (1, 0), (2, 0) and (3, 0) Phillips bands A1{\Pi}u-X1{\Sigma}+g. We report on the identification of a few lines of the C2 (4, 0) Phillips system towards HD 147889. The curve-of-growth method is applied to the equivalent widths to determine the column densities of the individual rotational levels of C2. The excitation temperature is extracted from the rotational diagrams. The physical parameters of the intervening molecular clouds (e.g. gas kinetic temperatures and densities of collision partners) were estimated by comparison with the theoretical model of excitation of C2.Comment: 11 pages, 3 figures, MNRAS 201

Diagnosis and management of an immature teratoma during ovarian stimulation: a case report

<p>Abstract</p> <p>Introduction</p> <p>The discovery of a mature teratoma (dermoid cyst) of the ovary during ovarian stimulation is not a rare event. Conversely, we could not find any reported cases of immature teratoma in such a situation. Clinical and ultrasound arguments for this immature form are scarcely or poorly evaluated.</p> <p>Case Presentation</p> <p>We describe the case of a 31-year-old Caucasian woman with primary infertility, who developed an immature teratoma during an in vitro fertilization ovarian stimulation cycle.</p> <p>Conclusions</p> <p>Ultrasound signs of an atypical cyst during ovarian stimulation allowed us to adopt a careful medical attitude and to adapt the required surgical oncological treatment.</p

Foliar lead uptake by lettuce exposed to atmospheric fallouts

Metal uptake by plants occurs by soil−root transfer but also by direct transfer of contaminants from the atmosphere to the shoots. This second pathway may be particularly important in kitchen gardens near industrial plants. The mechanisms of foliar uptake of lead by lettuce (Lactuca sativa) exposed to the atmospheric fallouts of a lead-recycling plant were studied. After 43 days of exposure, the thoroughly washed leaves contained 335 ± 50 mg Pb kg−1 (dry weight). Micro-X-ray fluorescence mappings evidenced Pb-rich spots of a few hundreds of micrometers in diameter located in necrotic zones. These spots were more abundant at the base of the central nervure. Environmental scanning electron microscopy coupled with energy dispersive X-ray microanalysis showed that smaller particles (a few micrometers in diameter) were also present in other regions of the leaves, often located beneath the leaf surface. In addition, submicrometric particles were observed inside stomatal openings. Raman microspectrometry analyses of the leaves identified smelter-originated Pb minerals but also secondary phases likely resulting from the weathering of original particles. On the basis of these observations, several pathways for foliar lead uptake are discussed. A better understanding of these mechanisms may be of interest for risk assessment of population exposure to atmospheric metal contamination

O papel social e economica da mulher imigrante na região de Venda Nova do Imigrante (ES) - 1891 A 1927

Dissertação apresentada no Pragrma de Pós- Graduação de Históri