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1.
  • Blokland, G. A. M., et al. (author)
  • Sex-Dependent Shared and Nonshared Genetic Architecture Across Mood and Psychotic Disorders
  • 2022
  • In: Biological Psychiatry. - : Elsevier BV. - 0006-3223 .- 1873-2402. ; 91:1, s. 102-117
  • Journal article (peer-reviewed)abstract
    • Background: Sex differences in incidence and/or presentation of schizophrenia (SCZ), major depressive disorder (MDD), and bipolar disorder (BIP) are pervasive. Previous evidence for shared genetic risk and sex differences in brain abnormalities across disorders suggest possible shared sex-dependent genetic risk. Methods: We conducted the largest to date genome-wide genotype-by-sex (G×S) interaction of risk for these disorders using 85,735 cases (33,403 SCZ, 19,924 BIP, and 32,408 MDD) and 109,946 controls from the PGC (Psychiatric Genomics Consortium) and iPSYCH. Results: Across disorders, genome-wide significant single nucleotide polymorphism–by-sex interaction was detected for a locus encompassing NKAIN2 (rs117780815, p = 3.2 × 10−8), which interacts with sodium/potassium-transporting ATPase (adenosine triphosphatase) enzymes, implicating neuronal excitability. Three additional loci showed evidence (p < 1 × 10−6) for cross-disorder G×S interaction (rs7302529, p = 1.6 × 10−7; rs73033497, p = 8.8 × 10−7; rs7914279, p = 6.4 × 10−7), implicating various functions. Gene-based analyses identified G×S interaction across disorders (p = 8.97 × 10−7) with transcriptional inhibitor SLTM. Most significant in SCZ was a MOCOS gene locus (rs11665282, p = 1.5 × 10−7), implicating vascular endothelial cells. Secondary analysis of the PGC-SCZ dataset detected an interaction (rs13265509, p = 1.1 × 10−7) in a locus containing IDO2, a kynurenine pathway enzyme with immunoregulatory functions implicated in SCZ, BIP, and MDD. Pathway enrichment analysis detected significant G×S interaction of genes regulating vascular endothelial growth factor receptor signaling in MDD (false discovery rate-corrected p < .05). Conclusions: In the largest genome-wide G×S analysis of mood and psychotic disorders to date, there was substantial genetic overlap between the sexes. However, significant sex-dependent effects were enriched for genes related to neuronal development and immune and vascular functions across and within SCZ, BIP, and MDD at the variant, gene, and pathway levels. © 2021 Society of Biological Psychiatry
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11.
  • Lis, D. C., et al. (author)
  • Herschel/HIFI measurements of the ortho/para ratio in water towards Sagittarius B2(M) and W31C
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1, s. Article Number: L26 -
  • Journal article (peer-reviewed)abstract
    • We present Herschel/HIFI observations of the fundamental rotational transitions of ortho- and para-H216O and H218O in absorption towards Sagittarius B2(M) and W31C. The ortho/para ratio in water in the foreground clouds on the line of sight towards these bright continuum sources is generally consistent with the statistical high-temperature ratio of 3, within the observational uncertainties. However, somewhat unexpectedly, we derive a low ortho/para ratio of 2.35 +/- 0.35, corresponding to a spin temperature of similar to 27 K, towards Sagittarius B2(M) at velocities of the expanding molecular ring. Water molecules in this region appear to have formed with, or relaxed to, an ortho/para ratio close to the value corresponding to the local temperature of the gas and dust.
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12.
  • Ng, M Y M, et al. (author)
  • Meta-analysis of 32 genome-wide linkage studies of schizophrenia
  • 2009
  • In: Molecular Psychiatry. - : Springer Science and Business Media LLC. - 1359-4184 .- 1476-5578. ; 14:8, s. 774-785
  • Journal article (peer-reviewed)abstract
    • A genome scan meta-analysis (GSMA) was carried out on 32 independent genome-wide linkage scan analyses that included 3255 pedigrees with 7413 genotyped cases affected with schizophrenia (SCZ) or related disorders. The primary GSMA divided the autosomes into 120 bins, rank-ordered the bins within each study according to the most positive linkage result in each bin, summed these ranks (weighted for study size) for each bin across studies and determined the empirical probability of a given summed rank (P(SR)) by simulation. Suggestive evidence for linkage was observed in two single bins, on chromosomes 5q (142-168 Mb) and 2q (103-134 Mb). Genome-wide evidence for linkage was detected on chromosome 2q (119-152 Mb) when bin boundaries were shifted to the middle of the previous bins. The primary analysis met empirical criteria for 'aggregate' genome-wide significance, indicating that some or all of 10 bins are likely to contain loci linked to SCZ, including regions of chromosomes 1, 2q, 3q, 4q, 5q, 8p and 10q. In a secondary analysis of 22 studies of European-ancestry samples, suggestive evidence for linkage was observed on chromosome 8p (16-33 Mb). Although the newer genome-wide association methodology has greater power to detect weak associations to single common DNA sequence variants, linkage analysis can detect diverse genetic effects that segregate in families, including multiple rare variants within one locus or several weakly associated loci in the same region. Therefore, the regions supported by this meta-analysis deserve close attention in future studies.
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13.
  • Falgarone, E., et al. (author)
  • CH+(1-0) and 13CH+(1-0) absorption lines in the direction of massive star-forming regions
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1
  • Journal article (peer-reviewed)abstract
    • We report the detection of the ground-state rotational transition of the methylidyne cation CH+ and its isotopologue (CH+)-C-13 toward the remote massive star-forming regions W33A, W49N, and W51 with the HIFI instrument onboard the Herschel satellite. Both lines are seen only in absorption against the dust continuum emission of the star-forming regions. The CH+ absorption is saturated over almost the entire velocity ranges sampled by the lines-of-sight that include gas associated with the star-forming regions (SFR) and Galactic foreground material. The CH+ column densities are inferred from the optically thin components. A lower limit of the isotopic ratio [(CH+)-C-12]/[(CH+)-C-13]> 35.5 is derived from the absorptions of foreground material toward W49N. The column density ratio, N(CH+)/N(HCO+), is found to vary by at least a factor 10, between 4 and > 40, in the Galactic foreground material. Line-of-sight 12CH+ average abundances relative to total hydrogen are estimated. Their average value, N(CH+)/NH > 2.6 x 10(-8), is higher than that observed in the solar neighborhood and confirms the high abundances of CH+ in the Galactic interstellar medium. We compare this result to the predictions of turbulent dissipation regions (TDR) models and find that these high abundances can be reproduced for the inner Galaxy conditions. It is remarkable that the range of predicted N(CH+)/ N(HCO+) ratios, from 1 to similar to 50, is comparable to that observed.
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14.
  • Berne, Olivier, et al. (author)
  • PDRs4All : A JWST Early Release Science Program on Radiative Feedback from Massive Stars
  • 2022
  • In: Publications of the Astronomical Society of the Pacific. - : IOP Publishing. - 0004-6280 .- 1538-3873. ; 134:1035
  • Journal article (peer-reviewed)abstract
    • Massive stars disrupt their natal molecular cloud material through radiative and mechanical feedback processes. These processes have profound effects on the evolution of interstellar matter in our Galaxy and throughout the universe, from the era of vigorous star formation at redshifts of 1-3 to the present day. The dominant feedback processes can be probed by observations of the Photo-Dissociation Regions (PDRs) where the far-ultraviolet photons of massive stars create warm regions of gas and dust in the neutral atomic and molecular gas. PDR emission provides a unique tool to study in detail the physical and chemical processes that are relevant for most of the mass in inter- and circumstellar media including diffuse clouds, proto-planetary disks, and molecular cloud surfaces, globules, planetary nebulae, and star-forming regions. PDR emission dominates the infrared (IR) spectra of star-forming galaxies. Most of the Galactic and extragalactic observations obtained with the James Webb Space Telescope (JWST) will therefore arise in PDR emission. In this paper we present an Early Release Science program using the MIRI, NIRSpec, and NIRCam instruments dedicated to the observations of an emblematic and nearby PDR: the Orion Bar. These early JWST observations will provide template data sets designed to identify key PDR characteristics in JWST observations. These data will serve to benchmark PDR models and extend them into the JWST era. We also present the Science-Enabling products that we will provide to the community. These template data sets and Science-Enabling products will guide the preparation of future proposals on star-forming regions in our Galaxy and beyond and will facilitate data analysis and interpretation of forthcoming JWST observations.
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15.
  • Gerin, M., et al. (author)
  • Interstellar CH absorption in the diffuse interstellar medium along the sight-lines to G10.6-0.4 (W31C), W49N, and W51
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1, s. Article Number: L16-
  • Journal article (peer-reviewed)abstract
    • We report the detection of the ground state N, J = 1, 3/2 -> 1, 1/2 doublet of the methylidyne radical CH at similar to 532 GHz and similar to 536 GHz with the Herschel/ HIFI instrument along the sight-line to the massive star-forming regions G10.6-0.4 (W31C), W49N, and W51. While the molecular cores associated with these massive star-forming regions show emission lines, clouds in the diffuse interstellar medium are detected in absorption against the strong submillimeter background. The combination of hyperfine structure with emission and absorption results in complex profiles, with overlap of the different hyperfine components. The opacities of most of the CH absorption features are linearly correlated with those of CCH, CN, and HCO+ in the same velocity intervals. In specific narrow velocity intervals, the opacities of CN and HCO+ deviate from the mean trends, giving rise to more opaque absorption features. We propose that CCH can be used as another tracer of the molecular gas in the absence of better tracers, with [CCH]/[H2] similar to 3.2 +/- 1.1 x 10-8. The observed [CN]/[CH], [CCH]/[CH] abundance ratios suggest that the bulk of the diffuse matter along the lines of sight has gas densities nH = n(H) + 2n(H2) ranging between 100 and 1000 cm-3).
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16.
  • Gerin, M., et al. (author)
  • Interstellar OH+, H2O+ and H3O+ along the sight-line to G10.6-0.4
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 518:4, s. 110-
  • Journal article (peer-reviewed)abstract
    • We report the detection of absorption lines by the reactive ions OH+, H2O+ and H3O+ along the line of sight to the submillimeter continuum source G10.6$-$0.4 (W31C). We used the Herschel HIFI instrument in dual beam switch mode to observe the ground state rotational transitions of OH+ at 971 GHz, H2O+ at 1115 and 607 GHz, and H3O+ at 984 GHz. The resultant spectra show deep absorption over a broad velocity range that originates in the interstellar matter along the line of sight to G10.6$-$0.4 as well as in the molecular gas directly associated with that source. The OH+ spectrum reaches saturation over most velocities corresponding to the foreground gas, while the opacity of the H2O+ lines remains lower than 1 in the same velocity range, and the H3O+ line shows only weak absorption. For LSR velocities between 7 and 50 kms$^{-1}$ we estimate total column densities of $N$(OH+) $> 2.5 \times 10^{14}$ cm$^{-2}$, $N$(H2O+) $\sim 6 \times 10^{13}$ cm$^{-2}$ and $N$(H3O+) $\sim 4.0 \times 10^{13}$ cm$^{-2}$. These detections confirm the role of O$^+$ and OH$^+$ in initiating the oxygen chemistry in diffuse molecular gas and strengthen our understanding of the gas phase production of water. The high ratio of the OH+ by the H2O+ column density implies that these species predominantly trace low-density gas with a small fraction of hydrogen in molecular form.
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17.
  • Neufeld, D. A., et al. (author)
  • Herschel/HIFI observations of interstellar OH+ and H2O+ towards W49N: a probe of diffuse clouds with a small molecular fraction
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1, s. Article Number: L10-
  • Journal article (peer-reviewed)abstract
    • We report the detection of absorption by interstellar hydroxyl cations and water cations, along the sight-line to the bright continuum source W49N. We have used Herschel's HIFI instrument, in dual beam switch mode, to observe the 972 GHz N = 1-0 transition of OH+ and the 1115 GHz 1(11)-0(00) transition of ortho-H2O+. The resultant spectra show absorption by ortho-H2O+, and strong absorption by OH+, in foreground material at velocities in the range 0 to 70 km s(-1) with respect to the local standard of rest. The inferred OH+/H2O+ abundance ratio ranges from similar to 3 to similar to 15, implying that the observed OH+ arises in clouds of small molecular fraction, in the 2-8% range. This conclusion is confirmed by the distribution of OH+ and H2O+ in Doppler velocity space, which is similar to that of atomic hydrogen, as observed by means of 21 cm absorption measurements, and dissimilar from that typical of other molecular tracers. The observed OH+/H abundance ratio of a few x10(-8) suggests a cosmic ray ionization rate for atomic hydrogen of 0.6-2.4 x 10(-16) s(-1), in good agreement with estimates inferred previously for diffuse clouds in the Galactic disk from observations of interstellar H-3(+) and other species.
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18.
  • Sonnentrucker, P., et al. (author)
  • Detection of hydrogen fluoride absorption in diffuse molecular clouds with Herschel/HIFI: an ubiquitous tracer of molecular gas
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1, s. Article Number: L12-
  • Journal article (peer-reviewed)abstract
    • We discuss the detection of absorption by interstellar hydrogen fluoride (HF) along the sight line to the submillimeter continuum sources W49N and W51. We have used Herschel's HIFI instrument in dual beam switch mode to observe the 1232.4762 GHz J = 1-0 HF transition in the upper sideband of the band 5a receiver. We detected foreground absorption by HF toward both sources over a wide range of velocities. Optically thin absorption components were detected on both sight lines, allowing us to measure - as opposed to obtain a lower limit on - the column density of HF for the first time. As in previous observations of HF toward the source G10.6-0.4, the derived HF column density is typically comparable to that of water vapor, even though the elemental abundance of oxygen is greater than that of fluorine by four orders of magnitude. We used the rather uncertain N(CH) - N(H-2) relationship derived previously toward diffuse molecular clouds to infer the molecular hydrogen column density in the clouds exhibiting HF absorption. Within the uncertainties, we find that the abundance of HF with respect to H-2 is consistent with the theoretical prediction that HF is the main reservoir of gas-phase fluorine for these clouds. Thus, hydrogen fluoride has the potential to become an excellent tracer of molecular hydrogen, and provides a sensitive probe of clouds of small H-2 column density. Indeed, the observations of hydrogen fluoride reported here reveal the presence of a low column density diffuse molecular cloud along the W51 sight line, at an LSR velocity of similar to 24 km s(-1), that had not been identified in molecular absorption line studies prior to the launch of Herschel.
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19.
  • Indriolo, N., et al. (author)
  • Herschel Survey of Galactic OH+, H2O+, and H3O+: Probing the Molecular Hydrogen Fraction and Cosmic-Ray Ionization Rate
  • 2015
  • In: Astrophysical Journal. - 1538-4357 .- 0004-637X. ; 800:1, s. 40-
  • Journal article (peer-reviewed)abstract
    • In diffuse interstellar clouds the chemistry that leads to the formation of the oxygen-bearing ions OH+, H2O+, and H3O+ begins with the ionization of atomic hydrogen by cosmic rays, and continues through subsequent hydrogen abstraction reactions involving H2. Given these reaction pathways, the observed abundances of these molecules are useful in constraining both the total cosmic-ray ionization rate of atomic hydrogen (ζH) and molecular hydrogen fraction (f_H_2). We present observations targeting transitions of OH+, H2O+, and H3O+ made with the Herschel Space Observatory along 20 Galactic sight lines toward bright submillimeter continuum sources. Both OH+ and H2O+ are detected in absorption in multiple velocity components along every sight line, but H3O+ is only detected along 7 sight lines. From the molecular abundances we compute f_H_2 in multiple distinct components along each line of sight, and find a Gaussian distribution with mean and standard deviation 0.042 ± 0.018. This confirms previous findings that OH+ and H2O+ primarily reside in gas with low H2 fractions. We also infer ζH throughout our sample, and find a lognormal distribution with mean log (ζH) = –15.75 (ζH = 1.78 × 10–16 s–1) and standard deviation 0.29 for gas within the Galactic disk, but outside of the Galactic center. This is in good agreement with the mean and distribution of cosmic-ray ionization rates previously inferred from H_3^+ observations. Ionization rates in the Galactic center tend to be 10-100 times larger than found in the Galactic disk, also in accord with prior studies.
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  • Mookerjea, B., et al. (author)
  • Excitation and abundance of C3 in star forming cores Herschel/HIFI observations of the sight-lines to W31C and W49N
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1, s. Article Number: L13 -
  • Journal article (peer-reviewed)abstract
    • We present spectrally resolved observations of triatomic carbon (C-3) in several ro-vibrational transitions between the vibrational ground state and the low-energy nu(2) bending mode at frequencies between 1654-1897 GHz along the sight-lines to the submillimeter continuum sources W31C and W49N, using Herschel's HIFI instrument. We detect C-3 in absorption arising from the warm envelope surrounding the hot core, as indicated by the velocity peak position and shape of the line profile. The sensitivity does not allow to detect C-3 absorption due to diffuse foreground clouds. From the column densities of the rotational levels in the vibrational ground state probed by the absorption we derive a rotation temperature (T-rot) of similar to 50-70 K, which is a good measure of the kinetic temperature of the absorbing gas, as radiative transitions within the vibrational ground state are forbidden. It is also in good agreement with the dust temperatures for W31C and W49N. Applying the partition function correction based on the derived T-rot, we get column densities N(C-3) similar to 7-9 x 10(14) cm(-2) and abundance x(C-3) similar to 10(-8) with respect to H-2. For W31C, using a radiative transfer model including far-infrared pumping by the dust continuum and a temperature gradient within the source along the line of sight we find that a model with x(C-3) = 10(-8), T-kin = 30-50 K, N(C-3) = 1.5 x 10(15) cm(-2) fits the observations reasonably well and provides parameters in very good agreement with the simple excitation analysis.
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22.
  • Neufeld, D.A., et al. (author)
  • Strong absorption by interstellar hydrogen fluoride: Herschel/HIFI observations of the sight-line to G10.6-0.4 (W31C)
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 518:4, s. 108-
  • Journal article (peer-reviewed)abstract
    • We report the detection of strong absorption by interstellar hydrogen fluoride along the sight-line to the submillimeter continuum source G10.6-0.4 (W31C). We have used Herschel's HIFI instrument, in dual beam switch mode, to observe the 1232.4763 GHz J=1-0 HF transition in the upper sideband of the Band 5a receiver. The resultant spectrum shows weak HF emission from G10.6-0.4 at LSR velocities in the range -10 to -3 km/s, accompanied by strong absorption by foreground material at LSR velocities in the range 15 to 50 km/s. The spectrum is similar to that of the 1113.3430 GHz 1(11)-0(00) transition of para-water, although at some frequencies the HF (hydrogen fluoride) optical depth clearly exceeds that of para-H2O. The optically-thick HF absorption that we have observed places a conservative lower limit of 1.6E+14 cm-2 on the HF column density along the sight-line to G10.6-0.4. Our lower limit on the HF abundance, 6E-9 relative to hydrogen nuclei, implies that hydrogen fluoride accounts for between ~ 30 and 100% of the fluorine nuclei in the gas phase along this sight-line. This observation corroborates theoretical predictions that - because the unique thermochemistry of fluorine permits the exothermic reaction of F atoms with molecular hydrogen - HF will be the dominant reservoir of interstellar fluorine under a wide range of conditions.
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23.
  • Persson, Carina, 1964, et al. (author)
  • Nitrogen hydrides in interstellar gas Herschel/HIFI observations towards G10.6-0.4 (W31C)
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1, s. Article Number: L45 -
  • Journal article (peer-reviewed)abstract
    • The HIFI instrument on board the Herschel Space Observatory has been used to observe interstellar nitrogen hydrides along the sight-line towards G10.6-0.4 in order to improve our understanding of the interstellar chemistry of nitrogen. We report observations of absorption in NH N = 1
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25.
  • Dherbecourt, J. B., et al. (author)
  • Design and pre-development of an airborne multi-species differential absorption Lidar system for water vapor and HDO isotope, carbon dioxide, and methane observation
  • 2021
  • In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE-Intl Soc Optical Eng.
  • Conference paper (peer-reviewed)abstract
    • We report on the current design and preliminary developments of the airborne Lidar Emitter and Multi-species greenhouse gases Observation iNstrument (LEMON), which is aiming at probing H2O and its isotope HDO at 1982 nm, CO2 at 2051 nm, and potentially CH4 at 2290 nm, with the Differential Absorption Lidar method (DIAL). The infrared emitter is based on the combination of two Nested Cavity OPOs (NesCOPOs) with a single optical parametric amplifier (OPA) line for high-energy pulse generation. This configuration is enabled by the use of high-aperture periodically poled KTP crystals (PPKTP), which provide efficient amplification in the spectral range of interest around 2 μm with slight temperature adjustments. The parametric stages are pumped with a Nd:YAG laser providing 200 mJ nanosecond double pulses at 75 Hz. According to parametric conversion simulations supported by current laboratory experiments, output energies in the 40 - 50 mJ range are expected in the extracted signal beam whilst maintaining a good beam quality (M2 < 2). The ruler for all the optical frequencies involved in the system is planned to be provided by a GPS referenced frequency comb with large mode spacing (1 GHz) against which the emitter output pulses can be heterodyned. The frequency precision measurement is expected to be better than 200 kHz for the optical frequencies of interest. The presentation will give an overview of the key elements of design and of preliminary experimental characterizations of sub-systems building blocks. 
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26.
  • Dherbecourt, Jean Baptiste, et al. (author)
  • Injection-Free and Cavity Free Parametric Sources for Future Spaceborne DIAL Based on Periodically Poled Nonlinear Materials
  • 2024
  • In: Springer Aerospace Technology. - : Springer Nature. ; , s. 363-371
  • Book chapter (other academic/artistic)abstract
    • We present new parametric source architectures for future spaceborne Differential Absorption Lidar (DIAL). This work focalizes on the developments performed during LEMON H2020 project using periodically poled nonlinear crystals. Such phase matching configuration offers the possibility to go towards more simple and robust set-ups for future space operation. We investigated injection-free optical parametric oscillator OPO set-ups, such as the Nested Cavity OPO–which allows a broad tuning range and thus can address several gas species with a single OPO—and also propose an injection and cavity free OPO solution using the counter-propagating phase matching configuration (Backward wave OPO). Moreover, we studied the implementation of high efficiency optical parametric amplifiers, to investigate the possibility to scale the output energies to several tens of mJ in the 2 µm region, and performed radiation testing on the specifically developed, large aperture, periodically poled KTP crystals.
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27.
  • Dherbecourt, J. B., et al. (author)
  • Lidar Emitter and Multi-species greenhouse gases Observation iNstrument (LEMON) : advances on a multi-species differential absorption Lidar system
  • 2022
  • In: 73rd International Astronautical Congress, IAC 2022. - : International Astronautical Federation, IAF.
  • Conference paper (peer-reviewed)abstract
    • In the frame of LEMON project (Lidar Emitter and Multi-species greenhouse gases Observation iNstrument - European Union's Horizon 2020 research and innovation program, GA n°821868), we are developing a multi-species differential absorption Lidar (DIAL). The goal is to benefit from innovative technological developments in terms of optical emitter, spectral reference, to be able to address H2O and its isotope HDO at 1982 nm, CO2 at 2051 nm, and potentially CH4 at 2290 nm, for future ground-based range-resolved DIAL sensing, and with the prospect of future airborne integrated-path DIAL (IPDA). The infrared emitter is based on the combination of two specific, patented, no-seeder Nested Cavity OPOs (NesCOPOs) coupled to a single optical parametric amplifier (OPA) line for high energy pulses generation. Specific developments are also pursued on the frequency reference for the emitter, which is planned to be provided by a GPS referenced frequency comb against which the emitter output pulses can be heterodyned. Besides the instrument design, specific tests experiments have been carried out, covering a wide panel of activities: radiation testing of some critical components to assess the potential of some key components for future space applications, emitter and frequency reference testing, preliminary DIAL tests with laboratory test-beds and comparison with specific in-situ calibration instruments as well as additional innovative techniques evaluation for the emitter. The final instrument design was carried out and the sub-units are now being built.
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28.
  • Godard, B, et al. (author)
  • Provision of genetic services in Europe: current practices and issues
  • 2003
  • In: European Journal of Human Genetics. - : Springer Science and Business Media LLC. - 1476-5438 .- 1018-4813. ; 11, s. 13-48
  • Journal article (peer-reviewed)abstract
    • This paper examines the professional and scientific views on the social, ethical and legal issues that impact on the provision of genetic services in Europe. Many aspects have been considered, such as the definition and the aims of genetic services, their organization, the quality assessment, public education, as well as the partnership with patients support groups and the multicultural aspects. The methods was primarily the analysis of professional guidelines, legal frameworks and other documents related to the organization of genetic services, mainly from Europe, but also from USA and international organizations. Then, the method was to examine the background data emerging from an updated report produced by the Concerted Action on Genetic Services in Europe, as well as the issues debated by 43 experts from 17 European countries invited to an international workshop organized by the European Society of Human Genetics Public and Professional Policy Committee in Helsinki, Finland, 8 and 9 September 2000. Some conclusions were identified from the ESHG workshop to arrive at outlines for optimal genetic services. Participants were concerned about equal accessibility and effectiveness of clinical genetic services, quality assessment of services, professional education, multidisciplinarity and division of tasks as well as networking. Within European countries, adherance to the organizational principles of prioritization, regionalization and integration into related health services would maximize equal accessibility and effectiveness of genetic actions. There is a need for harmonization of the rules involved in financial coverage of DNA tests in order to make these available to all Europeans. Clear guidelines for the best practice will ensure that the provision of genetic services develops in a way that is beneficial to its customers, be they health professionals or the public, especially since the coordination of clinical, laboratory and research perspectives within a single organizational structure permits a degree of coherence not often found in other specialties.
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29.
  • Lis, D. C., et al. (author)
  • Widespread Rotationally Hot Hydronium Ion in the Galactic Interstellar Medium
  • 2014
  • In: Astrophysical Journal. - 1538-4357 .- 0004-637X. ; 785:2, s. A135, pp. 1-9
  • Journal article (peer-reviewed)abstract
    • We present new Herschel observations of the (6,6) and (9,9) inversion transitions of the hydronium ion toward Sagittarius B2(N) and W31C. Sensitive observations toward Sagittarius B2(N) show that the high, ~500 K, rotational temperatures characterizing the population of the highly excited metastable H3O+ rotational levels are present over a wide range of velocities corresponding to the Sagittarius B2 envelope, as well as the foreground gas clouds between the Sun and the source. Observations of the same lines toward W31C, a line of sight that does not intersect the Central Molecular Zone but instead traces quiescent gas in the Galactic disk, also imply a high rotational temperature of ~380 K, well in excess of the kinetic temperature of the diffuse Galactic interstellar medium. While it is plausible that some fraction of the molecular gas may be heated to such high temperatures in the active environment of the Galactic center, characterized by high X-ray and cosmic-ray fluxes, shocks, and high degree of turbulence, this is unlikely in the largely quiescent environment of the Galactic disk clouds. We suggest instead that the highly excited states of the hydronium ion are populated mainly by exoergic chemical formation processes and the temperature describing the rotational level population does not represent the physical temperature of the medium. The same arguments may be applicable to other symmetric top rotors, such as ammonia. This offers a simple explanation of the long-standing puzzle of the presence of a pervasive, hot molecular gas component in the central region of the Milky Way. Moreover, our observations suggest that this is a universal process not limited to the active environments associated with galactic nuclei.
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30.
  • Löfdahl, Claes-Göran, et al. (author)
  • Randomised, placebo controlled trial of effect of a leukotriene receptor antagonist, montelukast, on tapering inhaled corticosteroids in asthmatic patients
  • 1999
  • In: BMJ. - 0959-8138. ; 319:7202, s. 87-90
  • Journal article (peer-reviewed)abstract
    • OBJECTIVE: To determine the ability of montelukast, a leukotriene receptor antagonist, to allow tapering of inhaled corticosteroids in clinically stable asthmatic patients. DESIGN: Double blind, randomised, placebo controlled, parallel group study. After a single blind placebo run in period, during which (at most) two inhaled corticosteroids dose decreases occurred, qualifying, clinically stable patients were allocated randomly to receive montelukast (10 mg tablet) or matching placebo once daily at bedtime for up to 12 weeks. SETTING: 23 academic asthma centres in United States, Canada, and Europe. PARTICIPANTS: 226 clinically stable patients with chronic asthma receiving high doses of inhaled corticosteroids (113 randomised to montelukast and 113 to placebo). INTERVENTIONS: Every 2 weeks, the inhaled corticosteroids dose was tapered, maintained, or increased (rescue) based on a standardised clinical score. MAIN OUTCOME MEASURES: Last tolerated dose of inhaled corticosteroids. RESULTS: Compared with placebo, montelukast allowed significant (P=0. 046) reduction in the inhaled corticosteroid dose (montelukast 47% v placebo 30%; least square mean difference 17.6%, 95% confidence interval 0.3 to 34.8). Fewer patients on montelukast (18 (16%) v 34 (30%) placebo, P=0.01) required discontinuation because of failed rescue. CONCLUSIONS: Montelukast reduces the need for inhaled corticosteroids among patients requiring moderate to high doses of corticosteroid to maintain asthma control.
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31.
  • Persson, Carina, 1964, et al. (author)
  • Nitrogen hydrides in interstellar gas II. Analysis of Herschel/HIFI observations towards W49N and G10.6-0.4 (W31C)
  • 2012
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 543:Article Number: A145, s. 145-179
  • Journal article (peer-reviewed)abstract
    • As a part of the Herschel key programme PRISMAS, we have used the Herschel-HIFI instrument to observe interstellar nitrogen hydrides along the sight-lines towards eight high-mass star-forming regions in order to elucidate the production pathways leading to nitrogen-bearing species in diffuse gas. Here, we report observations towards W49N of the NH N = 1 - 0, J = 2 - 1, and J = 1 - 0, ortho-NH2 N_(Ka, K_c) J = 1_(1,1) 3/2 - 0_(0,0) 1/2, ortho-NH3 J_K = 1_0 - 0_0 and 2_0 - 1_0, para-NH3 J_K = 2_1 - 1_1 transitions, and unsuccessful searches for NH+. All detections show absorption by foreground material over a wide range of velocities, as well as absorption associated directly with the hot-core source itself. As in the previously published observations towards G10.6-0.4, the NH, NH2 and NH3 spectra towards W49N show strikingly similar and non-saturated absorption features. We decompose the absorption of the foreground material towards W49N into different velocity components in order to investigate whether the relative abundances vary among the velocity components, and, in addition, we re-analyse the absorption lines towards G10.6-0.4 in the same manner. Abundances, with respect to molecular hydrogen, in each velocity component are estimated using CH, which is found to correlate with H2 in the solar neighbourhood diffuse gas. The analysis points to a co-existence of the nitrogen hydrides in diffuse or translucent interstellar gaswith a high molecular fraction. Towards both sources, we find that NH is always at least as abundant as both o-NH2 and o-NH3, in sharp contrast to previous results for dark clouds. We find relatively constant N(NH)/N(o-NH3) and N(o-NH2)/N(o-NH3) ratios with mean values of 3.2 and 1.9 towards W49N, and 5.4 and 2.2 towards G10.6-0.4, respectively. The mean abundance of o-NH4 is ~2x10^-9 towards both sources. The nitrogen hydrides also show linear correlations with CN and HNC towards both sources, and looser correlations with CH. The upper limits on the NH+ abundance indicate column densities
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32.
  • Persson, Carina, 1964, et al. (author)
  • Nitrogen hydrides in interstellar gas towards G10.6-0.4 (W31C) and W49N
  • 2011
  • In: IAU Symposium 280, Poster 76, Session 2, The Molecular Universe, Posters from the proceedings of the 280th Symposium of the International Astronomical Union held in Toledo, Spain, May 30-June 3, 2011, #296. ; 280:76
  • Conference paper (other academic/artistic)abstract
    • The PRISMAS key programme has used the HIFI instrument on board Herschel to observe interstellar nitrogen hydrides along the sight-lines towards G10.6-0.4 (W31C) and W49N in order to elucidate the production pathways leading to nitrogen bearing species. We report observations of the NH N=1-0, J=2-1 and J=1-0, ortho-NH2 111-000, ortho-NH3 10-00 and 20-10, para-NH3 21-11 transitions, and unsuccessful searches for NH+ in both sources. All detections show emission and absorption associated directly with the hot-core source itself as well as absorption by foreground material over a wide range of velocities. The NH, NH2 and NH3 spectra show strikingly similar and non-saturated absorption features, which we attribute to diffuse molecular gas. The similarity of the profiles suggest fairly uniform abundances relative to hydrogen. The derived relative and absolute abundances are discussed with reference to models of gas-phase and surface chemistry.
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33.
  • Schilke, P., et al. (author)
  • Ubiquitous argonium (ArH$^{+}$) in the diffuse interstellar medium: A molecular tracer of almost purely atomic gas
  • 2014
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 566:June, s. 1-12
  • Journal article (peer-reviewed)abstract
    • Aims: We describe the assignment of a previously unidentified interstellar absorption line to ArH+ and discuss its relevance in the context of hydride absorption in diffuse gas with a low H2 fraction. The confidence of the assignment to ArH+ is discussed, and the column densities are determined toward several lines of sight. The results are then discussed in the framework of chemical models, with the aim of explaining the observed column densities. Methods: We fitted the spectral lines with multiple velocity components, and determined column densities from the line-to-continuum ratio. The column densities of ArH+ were compared to those of other species, tracing interstellar medium (ISM) components with different H2 abundances. We constructed chemical models that take UV radiation and cosmic ray ionization into account. Results: Thanks to the detection of two isotopologues, 36ArH+ and 38ArH+, we are confident about the carrier assignment to ArH+. NeH+ is not detected with a limit of [NeH+]/[ArH+] ≤ 0.1. The derived column densities agree well with the predictions of chemical models. ArH+ is a unique tracer of gas with a fractional H2 abundance of 10-4 - 10-3 and shows little correlation to H2O+, which traces gas with a fractional H2 abundance of ≈0.1. Conclusions: A careful analysis of variations in the ArH+, OH+, H2O+, and HF column densities promises to be a faithful tracer of the distribution of the H2 fractional abundance by providing unique information on a poorly known phase in the cycle of interstellar matter and on its transition from atomic diffuse gas to dense molecular gas traced by CO emission. Abundances of these species put strong observational constraints upon magnetohydrodynamical (MHD)simulations of the interstellar medium, and potentially could evolve into a tool characterizing the ISM. Paradoxically, the ArH+ molecule is a better tracer of almost purely atomic hydrogen gas than Hi itself, since Hi can also be present in gas with a significant molecular content, but ArH+ singles out gas that is >99.9% atomic.
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