| 1. |
- Thomas, HS, et al.
(author)
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- 2019
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swepub:Mat__t
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| 2. |
- Tran, K. B., et al.
(author)
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The global burden of cancer attributable to risk factors, 2010-19: a systematic analysis for the Global Burden of Disease Study 2019
- 2022
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In: Lancet. - 0140-6736. ; 400:10352, s. 563-591
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Journal article (peer-reviewed)abstract
- Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.
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| 3. |
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| 4. |
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| 5. |
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| 6. |
- Adam, A, et al.
(author)
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Abstracts from Hydrocephalus 2016.
- 2017
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In: Fluids and Barriers of the CNS. - : Springer Science and Business Media LLC. - 2045-8118. ; 14:Suppl 1
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Journal article (peer-reviewed)
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| 7. |
- Abdulov, N. A., et al.
(author)
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TMDlib2 and TMDplotter : a platform for 3D hadron structure studies
- 2021
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In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 81:8
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Journal article (peer-reviewed)abstract
- A common library, TMDlib2, for Transverse-Momentum-Dependent distributions (TMDs) and unintegrated parton distributions (uPDFs) is described, which allows for easy access of commonly used TMDs and uPDFs, providing a three-dimensional (3D) picture of the partonic structure of hadrons. The tool TMDplotter allows for web-based plotting of distributions implemented in TMDlib2, together with collinear pdfs as available in LHAPDF.
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| 8. |
- Garcia-Lopez, R., et al.
(author)
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A measure of the size of the magnetospheric accretion region in TW Hydrae
- 2020
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 584:7822, s. 547-550
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Journal article (peer-reviewed)abstract
- Stars form by accreting material from their surrounding disks. There is a consensus that matter flowing through the disk is channelled onto the stellar surface by the stellar magnetic field. This is thought to be strong enough to truncate the disk close to the corotation radius, at which the disk rotates at the same rate as the star. Spectro-interferometric studies in young stellar objects show that hydrogen emission (a well known tracer of accretion activity) mostly comes from a region a few milliarcseconds across, usually located within the dust sublimation radius1–3. The origin of the hydrogen emission could be the stellar magnetosphere, a rotating wind or a disk. In the case of intermediate-mass Herbig AeBe stars, the fact that Brackett γ (Brγ) emission is spatially resolved rules out the possibility that most of the emission comes from the magnetosphere4–6 because the weak magnetic fields (some tenths of a gauss) detected in these sources7,8 result in very compact magnetospheres. In the case of T Tauri sources, their larger magnetospheres should make them easier to resolve. The small angular size of the magnetosphere (a few tenths of a milliarcsecond), however, along with the presence of winds9,10 make the interpretation of the observations challenging. Here we report optical long-baseline interferometric observations that spatially resolve the inner disk of the T Tauri star TW Hydrae. We find that the near-infrared hydrogen emission comes from a region approximately 3.5 stellar radii across. This region is within the continuum dusty disk emitting region (7 stellar radii across) and also within the corotation radius, which is twice as big. This indicates that the hydrogen emission originates in the accretion columns (funnel flows of matter accreting onto the star), as expected in magnetospheric accretion models, rather than in a wind emitted at much larger distance (more than one astronomical unit).
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| 9. |
- Koutoulaki, M., et al.
(author)
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The GRAVITY young stellar object survey: IV. The CO overtone emission in 51 Oph at sub-au scales
- 2021
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 645
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Journal article (peer-reviewed)abstract
- Context. 51 Oph is a Herbig Ae/Be star that exhibits strong near-infrared CO ro-vibrational emission at 2.3 μm, most likely originating in the innermost regions of a circumstellar disc. Aims. We aim to obtain the physical and geometrical properties of the system by spatially resolving the circumstellar environment of the inner gaseous disc. Methods. We used the second-generation Very Large Telescope Interferometer instrument GRAVITY to spatially resolve the continuum and the CO overtone emission. We obtained data over 12 baselines with the auxiliary telescopes and derive visibilities, and the differential and closure phases as a function of wavelength. We used a simple local thermal equilibrium ring model of the CO emission to reproduce the spectrum and CO line displacements. Results. Our interferometric data show that the star is marginally resolved at our spatial resolution, with a radius of ∼10.58 ± 2.65R·. The K-band continuum emission from the disc is inclined by 63° ± 1°, with a position angle of 116° ± 1°, and 4 ± 0.8 mas (0.5 ± 0.1 au) across. The visibilities increase within the CO line emission, indicating that the CO is emitted within the dust-sublimation radius. By modelling the CO bandhead spectrum, we derive that the CO is emitted from a hot (T = 1900-2800 K) and dense (NCO = (0.9-9) × 1021 cm-2) gas. The analysis of the CO line displacement with respect to the continuum allows us to infer that the CO is emitted from a region 0.10 ± 0.02 au across, well within the dust-sublimation radius. The inclination and position angle of the CO line emitting region is consistent with that of the dusty disc. Conclusions. Our spatially resolved interferometric observations confirm the CO ro-vibrational emission within the dust-free region of the inner disc. Conventional disc models exclude the presence of CO in the dust-depleted regions of Herbig AeBe stars. Ad hoc models of the innermost disc regions, that can compute the properties of the dust-free inner disc, are therefore required.
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| 10. |
- Abdulhamid, M. I., et al.
(author)
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Azimuthal correlations of high transverse momentum jets at next-to-leading order in the parton branching method
- 2022
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In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 82:1
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Journal article (peer-reviewed)abstract
- The azimuthal correlation, Δ ϕ12, of high transverse momentum jets in pp collisions at s=13 TeV is studied by applying PB-TMD distributions to NLO calculations via MCatNLO together with the PB-TMD parton shower. A very good description of the cross section as a function of Δ ϕ12 is observed. In the back-to-back region of Δ ϕ12→ π, a very good agreement is observed with the PB-TMD Set 2 distributions while significant deviations are obtained with the PB-TMD Set 1 distributions. Set 1 uses the evolution scale while Set 2 uses transverse momentum as an argument in αs, and the above observation therefore confirms the importance of an appropriate soft-gluon coupling in angular ordered parton evolution. The total uncertainties of the predictions are dominated by the scale uncertainties of the matrix element, while the uncertainties coming from the PB-TMDs and the corresponding PB-TMD shower are very small. The Δ ϕ12 measurements are also compared with predictions using MCatNLO together Pythia8, illustrating the importance of details of the parton shower evolution.
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| 11. |
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| 12. |
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| 13. |
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| 14. |
- Weigelt, G., et al.
(author)
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VLTI-MATISSE chromatic aperture-synthesis imaging of eta Carinae's stellar wind across the Br alpha line Periastron passage observations in February 2020
- 2021
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 652
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Journal article (peer-reviewed)abstract
- Context. Eta Carinae is a highly eccentric, massive binary system (semimajor axis similar to 15.5 au) with powerful stellar winds and a phase-dependent wind-wind collision (WWC) zone. The primary star, eta Car A, is a luminous blue variable (LBV); the secondary, eta Car B, is a Wolf-Rayet or O star with a faster but less dense wind. Aperture-synthesis imaging allows us to study the mass loss from the enigmatic LBV eta Car. Understanding LBVs is a crucial step toward improving our knowledge about massive stars and their evolution. Aims. Our aim is to study the intensity distribution and kinematics of eta Car's WWC zone. Methods. Using the VLTI-MATISSE mid-infrared interferometry instrument, we perform Br alpha imaging of eta Car's distorted wind. Results. We present the first VLTI-MATISSE aperture-synthesis images of eta Car A's stellar windin several spectral channels distributed across the Br alpha 4.052 mu m line (spectral resolving power R similar to 960). Our observations were performed close to periastron passage in February 2020 (orbital phase similar to 14.0022). The reconstructed iso-velocity images show the dependence of the primary stellar wind on wavelength or line-of-sight (LOS) velocity with a spatial resolution of 6 mas (similar to 14 au). The radius of the faintest outer wind regions is similar to 26 mas (similar to 60 au). At several negative LOS velocities, the primary stellar wind is less extended to the northwest than in other directions. This asymmetry is most likely caused by the WWC. Therefore, we see both the velocity field of the undisturbed primary wind and the WWC cavity. In continuum spectral channels, the primary star wind is more compact than in line channels. A fit of the observed continuum visibilities with the visibilities of a stellar wind CMFGEN model (CMFGEN is an atmosphere code developed to model the spectra of a variety of objects) provides a full width at half maximum fit diameter of the primary stellar wind of 2.84 +/- 0.06 mas (6.54 +/- 0.14 au). We comparethe derived intensity distributions with the CMFGEN stellar wind model and hydrodynamic WWC models.
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| 15. |
- Carlos, L. D., et al.
(author)
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Nanoscopic photoluminescence memory as a fingerprint of complexity in self-assembled alkyl/siloxane hybrids
- 2007
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In: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 19:3, s. 341-348
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Journal article (peer-reviewed)abstract
- A thermally activated photoluminescence memory effect, induced by a reversible order-disorder phase transition of the alkyl chains, is reported for highly organized bilayer alkyl/siloxane hybrids (see figure; left at room temperature, right at 120 degrees C). The emission energy is sensitive to the annihilation/formation of the hydrogen-bonded amide-amide array displaying a unique nanoscopic sensitivity (ca. 150 nm).
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| 16. |
- Chockalingam, P. S., et al.
(author)
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Elevated aggrecanase activity in a rat model of joint injury is attenuated by an aggrecanase specific inhibitor
- 2011
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In: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 19:3, s. 315-323
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Journal article (peer-reviewed)abstract
- Objective: To evaluate aggrecanase activity after traumatic knee injury in a rat model by measuring the level of aggrecanase-generated Ala-Arg-Gly-aggrecan (ARG-aggrecan) fragments in synovial fluid, and compare with ARG-aggrecan release into joint fluid following human knee injury. To evaluate the effect of small molecule inhibitors on induced aggrecanase activity in the rat model. Method: An enzyme-linked immunosorbent assay (ELISA) was developed to measure ARG-aggrecan levels in animal and human joint fluids. A rat model of meniscal tear (MT)-induced joint instability was used to assess ARG-aggrecan release into joint fluid and the effects of aggrecanase inhibition. Synovial fluids were also obtained from patients with acute joint injury or osteoarthritis and assayed for ARG-aggrecan. Results: Joint fluids from human patients after knee injury showed significantly enhanced levels of ARG-aggrecan compared to uninjured reference subjects. Similarly, synovial fluid ARG-aggrecan levels increased following surgically-induced joint instability in the rat MT model, which was significantly attenuated by orally dosing the animals with AGG-523, an aggrecanase specific inhibitor. Conclusions: Aggrecanase-generated aggrecan fragments were rapidly released into human and rat joint fluids after injury to the knee and remained elevated over a prolonged period. Our findings in human and preclinical models strengthen the connection between aggrecanase activity in joints and knee injury and disease. The ability of a small molecule aggrecanase inhibitor to reduce the release of aggrecanase-generated aggrecan fragments into rat joints suggests that pharmacologic inhibition of aggrecanase activity in humans may be an effective treatment for slowing cartilage degradation following joint injury. (C) 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
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| 17. |
- Garatti, A. Caratti o., et al.
(author)
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The GRAVITY young stellar object survey: II. First spatially resolved observations of the CO bandhead emission in a high-mass YSO
- 2020
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 635
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Journal article (peer-reviewed)abstract
- Context. The inner regions of the discs of high-mass young stellar objects (HMYSOs) are still poorly known due to the small angular scales and the high visual extinction involved. Aims. We deploy near-infrared spectro-interferometry to probe the inner gaseous disc in HMYSOs and investigate the origin and physical characteristics of the CO bandhead emission (2.3-2.4 m). Methods. We present the first GRAVITY/VLTI observations at high spectral (R = 4000) and spatial (mas) resolution of the CO overtone transitions in NGC2024 IRS 2. Results. The continuum emission is resolved in all baselines and is slightly asymmetric, displaying small closure phases (8). Our best ellipsoid model provides a disc inclination of 34 1, a disc major axis position angle (PA) of 166 1, and a disc diameter of 3:99 0:09 mas (or 1.69 0.04 au, at a distance of 423 pc). The small closure phase signals in the continuum are modelled with a skewed rim, originating from a pure inclination effect. For the first time, our observations spatially and spectrally resolve the first four CO bandheads. Changes in visibility, as well as differential and closure phases across the bandheads are detected. Both the size and geometry of the CO-emitting region are determined by fitting a bidimensional Gaussian to the continuum-compensated CO bandhead visibilities. The CO-emitting region has a diameter of 2.740:08 0:07 mas (1.16 0.03 au), and is located in the inner gaseous disc, well within the dusty rim, with inclination and PA matching the dusty disc geometry, which indicates that both dusty and gaseous discs are coplanar. Physical and dynamical gas conditions are inferred by modelling the CO spectrum. Finally, we derive a direct measurement of the stellar mass of M 14:7 M by combining our interferometric and spectral modelling results.
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| 18. |
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| 19. |
- Antonelli, Alexandre, 1978, et al.
(author)
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Geological and climatic influences on mountain biodiversity
- 2018
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In: Nature Geoscience. - : Springer Science and Business Media LLC. - 1752-0894 .- 1752-0908. ; 11:10
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Journal article (peer-reviewed)abstract
- Mountains are key features of the Earth's surface and host a substantial proportion of the world's species. However, the links between the evolution and distribution of biodiversity and the formation of mountains remain poorly understood. Here, we integrate multiple datasets to assess the relationships between species richness in mountains, geology and climate at global and regional scales. Specifically, we analyse how erosion, relief, soil and climate relate to the geographical distribution of terrestrial tetrapods, which include amphibians, birds and mammals. We find that centres of species richness correlate with areas of high temperatures, annual rainfall and topographic relief, supporting previous studies. We unveil additional links between mountain-building processes and biodiversity: species richness correlates with erosion rates and heterogeneity of soil types, with a varying response across continents. These additional links are prominent but under-explored, and probably relate to the interplay between surface uplift, climate change and atmospheric circulation through time. They are also influenced by the location and orientation of mountain ranges in relation to air circulation patterns, and how species diversification, dispersal and refugia respond to climate change. A better understanding of biosphere-lithosphere interactions is needed to understand the patterns and evolution of mountain biodiversity across space and time.
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| 20. |
- Bermudez, V. D., et al.
(author)
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Eu3+ coordination in an organic/inorganic hybrid matrix with methyl end-capped short polyether chains
- 2005
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In: Journal of Physical Chemistry B. - : American Chemical Society (ACS). - 1520-5207 .- 1520-6106. ; 109:15, s. 7110-7119
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Journal article (peer-reviewed)abstract
- Fourier Transform mid-infrared (FT-IR), Fourier Transform Raman (FT-Raman) and photoluminescence spectroscopies and Two-Dimensional (2D) Correlation Spectroscopic Analysis were employed to examine the anionic and cationic local environments in mono-urethanesils doped with europium triflate (Eu(CF 3-SO3)3). The hybrid host framework of these materials is composed of a siliceous backbone bonded through urethane linkages to CH3-terminated polymer chains containing about 7 OCH 2CH2 units. Samples with ∞ ≥ n (composition) ≥5 (where n = OCH2CH2/Eu3+) were studied. In terms of ionic association, the level of complexity of these xerogels is very high. In all the compounds the triflate ions exist "free", weakly coordinated and forming cross-link separated ion pairs. At 20 ≥ n ≥ 5, in addition to all these species contact ion pairs occur. In agreement with these conclusions, photoluminescence establishes the presence of three distinct cation local sites (Eu3+/O=C(urethane cross-links), Eu3+/O-C- C(polyether chains) and weakly coordinated Eu3+/CF3SO 3- ionic pairs).
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| 21. |
- Duarte, T. A. G., et al.
(author)
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A Glance at Novel Ionanofluids Incorporating Silk-Derived Carbon Dots
- 2024
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In: Chemistry of Materials. - : American Chemical Society (ACS). - 0897-4756 .- 1520-5002. ; 36:3, s. 1136-1152
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Journal article (peer-reviewed)abstract
- One of the hallmarks of the current efforts in the field of thermal energy is heat transfer enhancement. Ionanofluids (INFs), a combination of nanomaterials and ionic liquids (ILs), are an appealing category of thermal fluids. In this work, we introduce sustainable INFs composed of carbon dots derived from Bombyx mori silk fibroin (SF) dispersed in a mixture of 1-butyl-3-methylimidazolium chloride (IL1) and 1-(4-sulfobutyl)-3-methylimidazolium triflate (IL2). The syntheses were performed at mild conditions, with reaction times of 3, 4, and 5 h, and without purification steps. The INFs display room-temperature emission in the visible spectral range with quantum yield values up to 0.09 and are essentially viscous fluids (G″ > G′). A marked shear thinning behavior is observed at high shear rates, particularly for the systems SFIL1IL2-3h and SFIL1IL2-4h. The INFs demonstrate relatively high heat capacity and thermal conductivity values in comparison to state-of-the-art INFs. Under suitable illumination conditions, the INFs can convert light into heat in an efficient manner, with photothermal conversion efficiencies of up to 28%, similar to other reported INFs. SFIL1IL2-5h exhibits remarkable stability over time within the range of working temperatures. This work paves the way for the development of new thermal fluids for enhanced heat transfer technologies using sustainable synthesis routes and natural raw precursor materials.
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| 22. |
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| 23. |
- Garcia-Lopez, R., et al.
(author)
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The GRAVITY young stellar object survey XII. The hot gas disk component in Herbig Ae/Be stars
- 2024
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In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 684
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Journal article (peer-reviewed)abstract
- Context. The region of protoplanetary disks closest to a star (within 1–2 au) is shaped by a number of different processes, from accretion of the disk material onto the central star to ejection in the form of winds and jets. Optical and near-IR emission lines are potentially good tracers of inner disk processes if very high spatial and/or spectral resolution are achieved. Aims. In this paper, we exploit the capabilities of the VLTI-GRAVITY near-IR interferometer to determine the location and kinematics of the hydrogen emission line Brγ. Methods. We present VLTI-GRAVITY observations of the Brγ line for a sample of 26 stars of intermediate mass (HAEBE), the largest sample so far analysed with near-IR interferometry. Results. The Brγ line was detected in 17 objects. The emission is very compact (in most cases only marginally resolved), with a size of 10–30 R∗(1–5 mas). About half of the total flux comes from even smaller regions, which are unresolved in our data. For eight objects, it was possible to determine the position angle (PA) of the line-emitting region, which is generally in agreement with that of the inner-dusty disk emitting the K-band continuum. The position-velocity pattern of the Brγ line-emitting region of the sampled objects is roughly consistent with Keplerian rotation. The exception is HD 45677, which shows more extended emission and more complex kinematics. The most likely scenario for the Brγ origin is that the emission comes from an MHD wind launched very close to the central star, in a region well within the dust sublimation radius. An origin in the bound gas layer at the disk surface cannot be ruled out, while accreting matter provides only a minor fraction of the total flux. Conclusions. These results show the potential of near-IR spectro-interferometry to study line emission in young stellar objects.
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| 24. |
- Hayden, PJ, et al.
(author)
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Second allogeneic transplants for multiple myeloma: a report from the EBMT Chronic Malignancies Working Party
- 2021
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In: Bone marrow transplantation. - : Springer Science and Business Media LLC. - 1476-5365 .- 0268-3369. ; 56:10, s. 2367-2381
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Journal article (peer-reviewed)abstract
- The EBMT Chronic Malignancies Working Party performed a retrospective analysis of 215 patients who underwent a second allo-HCT for myeloma between 1994 and 2017, 159 for relapse and 56 for graft failure. In the relapse group, overall survival (OS) was 38% (30–46%) at 2 years and 25% (17–32%) at 5 years. Patients who had a HLA-identical sibling (HLAid-Sib) donor for their first and second transplants had superior OS (5 year OS: HLAid-Sib/HLAid-Sib: 35% (24–46%); Others 9% (0–17%), p < 0.001). There was a significantly higher incidence of acute grade II-IV GvHD in those patients who had also developed GvHD following their initial HLA-identical sibling allo-HCT (HLAid-Sib/HLAid-Sib: 50% (33–67%); Other 22% (8–36%), p = 0.03). More as opposed to fewer than 2 years between transplants was associated with superior 5-yr OS (31% (21–40%) vs. 10% (1–20%), P = 0.005). On multivariate analysis, consecutive HLA-identical sibling donor transplants conferred a significant OS advantage (0.4 (0.24–0.67), p < 0.001). In the graft failure group, OS was 41% at 2 years. In summary, a second allo-HCT using a HLA-identical sibling donor, if available, provides the best transplant outcomes for relapsed myeloma in this setting.
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| 25. |
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| 26. |
- Nunes, P., et al.
(author)
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The leaf of Agapanthus africanus (L.) Hoffm. : A physical-chemical perspective of terrestrialization in the cuticle
- 2023
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In: Environmental and Experimental Botany. - : Elsevier BV. - 0098-8472 .- 1873-7307. ; 208
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Journal article (peer-reviewed)abstract
- Although Agapanthus africanus (L.) Hoffm. is one of the most popular ornamental species in both hemispheres, it has an extremely restricted wild occurrence (Cape province, South Africa). This contradiction between gener-alized ornamental application and natural distribution was the basis for the analytical approach adopted in the present work. We hypothesized that characteristic features of the cuticular waxes were adopted by this species to help it cope with severe dehydration associated with marine salinity on account of the short distance of the wild populations to the sea. A comprehensive morpho-anatomical, histological and physical-chemical analysis was performed on the epicuticular and intracuticular layers of the adaxial and abaxial surfaces of leaves of specimens of A. africanus. The adaxial epicuticular surface is hydrophilic and the abaxial epicuticular surface exhibits globally hydrophobic behavior. The main chemical compounds detected in the wax layers of both surfaces of the leaf are the short-chain monocaprylin monoglyceride (C8), and very long-chain 1-hexacosanol (C26) and 1-octa-cosanol (C28) alcohols. While monocaprylin is particularly abundant in the intracuticular layers, the epicuticular adaxial surface revealed the highest concentration of both alcohols. We demonstrate that the smart combination of these two classes of molecules with opposite water affinity endows the A. africanus leaf cuticle with a unique water management system combining the efficient entrapment of water in the disordered alpha-gel phase formed by monocaprylin and the high resistance to water transport provided by ordered domains composed of tightly packed, all-trans alkyl chains of the above pair of alcohols. The remarkable structural similarity existing between the monocaprylin alpha-gel and the mucilage of algae is an evidence of the terrestrialization process.
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| 27. |
- Nunes, S. C., et al.
(author)
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Diurea cross-linked poly(oxyethylene)/siloxane ormolytes for lithium batteries
- 2005
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In: Journal of the Electrochemical Society. - : The Electrochemical Society. - 1945-7111 .- 0013-4651. ; 152:2
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Journal article (peer-reviewed)abstract
- Poly(oxyethylene) (POE)/siloxane hybrids (di-ureasils) doped with a wide concentration range of lithium triflate (LiCF3SO3) were investigated. The host matrix of these materials [d-U(2000)] is a sol-gel-derived siliceous framework to which POE chains with about 40.3 repeat units are bonded through urea linkages. Xerogels with ∞ ≥ n ≥ 5 (n is the molar ratio OCH2CH2/Li+) were obtained as amorphous monoliths thermally stable up to at least 340°C. A crystalline POE/LiCF3SO3 complex was detected spectroscopically in samples with n ≤ 10. Below 90°C the ormolyte with n = 20 exhibits the highest conductivity (5.8 × 10-6 n-l cm-1 at 26°C). The redox stability domain of this material spans 4.1 V. Although Fourier transform infrared spectroscopy data suggest that the Li+ ions are complexed by the POE ether oxygen atoms at n ≤10, this threshold composition is probably located at slightly lower salt content "Free" triflate ions and weakly coordinated anions, present in all the samples examined, must be the main charge carriers of the d-U(2000) 20LiCF3SO3 xerogel. Ion pairs (Li +CF3SO3-) or negatively charged triplets ([Li(CF3SO3)2]-) are formed at n ≤ 40. At n ≤ 5 positively charged triplets [Li2(CF 3SO3)]+ also appear. Divalent positively charged multiplets [Li3(CF3SO3)]2+ occur at n = 1.
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| 28. |
- Nunes, S. C., et al.
(author)
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Sol-gel-derived potassium-based di-ureasils for "smart windows''
- 2007
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In: Journal of Materials Chemistry. - : Royal Society of Chemistry (RSC). - 1364-5501 .- 0959-9428. ; 17:40, s. 4239-4248
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Journal article (peer-reviewed)abstract
- Sol-gel-derived KCF3SO3-doped di-urea cross-linked poly(oxyethylene) (POE)/siloxane (di-ureasil) ormolytes with infinity > n >= 1 (n is the number of oxyethylene units per K+ ion) have been analysed. Samples with n. 40 are thermally stable up to 310 degrees C. At n >= 100, POE crystallites are present. At n = 5, a crystalline POE-KCF3SO3 complex with stoichiometry 1 : 1 is formed. In the xerogel with n = 1 this complex coexists with free salt. The highest ionic conductivity is reached at n = 20. The redox stability domain of this material spans 5.0 V. "Free'' anions and weakly coordinated CF3SO3- ions appear to be the main charge carriers at n = 20. The K+ ions interact with the urea carbonyl oxygen atoms at all salt concentrations. Complexation of the cations by POE occurs at n
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| 29. |
- Nunes, S. C., et al.
(author)
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Structure and photoluminescence of di-amidosil nanohybrids incorporating europium triflate
- 2006
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In: Journal of Alloys and Compounds. - : Elsevier BV. - 0925-8388. ; 451:1-2, s. 510-515
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Conference paper (peer-reviewed)abstract
- The sol-gel process was used to prepare amorphous di-amide cross-linked alkyl/siloxane hybrid materials (di-amidosils) incorporating europium triflate (Eu(CF3SO3)(3)). Samples with 200 F-7(0-4) transitions. Photoluminescence data suggest that in the dilute di-amidosil with n = 100 the Eu3+ ions occupy the same type of chemical local environment. (C) 2007 Elsevier B.V. All rights reserved.
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| 30. |
- Nunes, S. C., et al.
(author)
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Structure and photoluminescent features of di-amide cross-linked alkylene-siloxane hybrids
- 2005
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In: Journal of Materials Chemistry. - : Royal Society of Chemistry (RSC). - 1364-5501 .- 0959-9428. ; 15:35-36, s. 3876-3886
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Journal article (peer-reviewed)abstract
- Novel amide cross-linked alkylene-siloxane hybrid materials (di-amidosils) synthesized by the sol-gel process have been investigated. Two samples identified by the notation d-A(x) with x = 4 and 8 (where x is the number of methylene groups of the alkylene chain) have been produced as transparent, amorphous, rigid monoliths. The d-A(8) material is thermally stable up to approximately 245°C. In this hybrid the siliceous framework is mainly composed of [-(CH2)Si(OSi)3)] and [-(CH 2)Si(OSi)2(OH)] substructures. Structural unit distances of 4.1 and 4.2 Å and average interparticle distances of 12 and 17 A have been determined for d-A(4) and d-A(8), respectively. In these compounds the alkylene chains are disordered and adopt gauche conformations. While a negligible proportion of the amide linkages remain non-bonded, the great majority of these groups belong to highly disordered strong hydrogen-bonded amide-amide associations. The hybrids introduced are room temperature white light emitters, presenting an intense, broad emission band in the blue/purplish-blue spectral region. The origin of such a band has been ascribed to the convolution of donor-acceptor pair (D-A) recombinations that occur in the NH groups of the amide linkages and in the siliceous nanodomains. The maximum quantum yield value of the d-A(8) di-amidosil is 5.4%.
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| 31. |
- Planquart, L., et al.
(author)
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An impressionist view of V Hydrae: When MATISSE paints asymmetric giant blobs
- 2024
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In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 687
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Journal article (peer-reviewed)abstract
- Context . Asymptotic giant branch (AGB) stars enrich the interstellar medium through their mass loss. The mechanism(s) shaping the circumstellar environment of mass-losing stars is not clearly understood so far. Aims. Our purpose is to study the effect of binary companions located within the first 10 stellar radii from the primary AGB star. In this work, we target the mass-losing carbon star V Hydrae (V Hya) and search for signatures of its companion in the dust-forming region of the atmosphere. Methods . The star was observed in the L and N bands with the VLTI/MATISSE instrument at low spectral resolution. We reconstructed images of the photosphere and surroundings of V Hya using the two bands and compared our interferometric observables with VLTI/MIDI and VISIR archival data. To constrain the dust properties, we used the 1D radiative transfer code DUSTY to model the spectral energy distribution. Results . The star is dominated by dust emission in the L- and N-bands. The MATISSE reconstructed images show asymmetric and elongated structures in both infrared bands. In the L band, we detected an elongated shape of approximately 15 mas that likely is of photospheric origin. In the N band, we found a 20 mas extension northeast from the star and perpendicular to the L-band elongated axis. The position angle and the size of the N-band extension match the prediction of the companion position at the MATISSE epoch. By comparing MATISSE N-band with MIDI data, we deduce that the elongation axis in the N-band has rotated since the previous interferometric measurements 13 yr ago, supporting the idea that the particle enhancement is related to the dusty clump moving along with the companion. The VISIR image confirms the presence of a large-scale dusty circumstellar envelope surrounding V Hya. Conclusions . The MATISSE images unveil the presence of a dust enhancement at the position of the companion. This opens new doors for further analyses of the binary interaction with an AGB component.
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| 32. |
- Rodriguez, S., et al.
(author)
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The Surfaces of the Ceratonia siliqua L. (Carob) Leaflet : Insights from Physics and Chemistry
- 2021
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In: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 37:6, s. 2011-2028
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Journal article (peer-reviewed)abstract
- The production of superhydrophobic coatings inspired by the surface of plant leaves is a challenging goal. Such coatings hold a bright technological future in niche markets of the aeronautical, space, naval, building, automobile, and biomedical sectors. This work is focused on the adaxial (top) and abaxial (bottom) surfaces of the leaflet of the Ceratonia silique L. (carob), a high-commercial-value Mediterranean tree cultivated in many regions of the world. The adaxial and abaxial surfaces feature hydrophobic and superhydrophobic behaviors, respectively. Their chemical composition is very simple: monopalmitin ester and palmitic acid are protuberant in the epicuticular and intracuticular wax layers of the adaxial surface, respectively, whereas 1-octacosanol dominates in the abaxial wax layers. In both surfaces, epicuticular wax is organized along a randomly oriented and intricate network of nanometer-thick and micrometer-long plates, whose density and degree of interconnection are significantly higher in the abaxial surface. The measured tilting angles for the abaxial surface (12-70 degrees) reveal unusual variable density and water adhesion of the nanostructured plate-based texture. Optical measurements demonstrate that light reflectance/absorbance of the glaucous abaxial surface is significantly higher/lower than that of the nonglaucous adaxial surface. In both surfaces, diffuse reflectance is dominant, and the absorbance is weakly dependent on the light incidence angle. We show that the highly dense nanostructured platelike texture of the epicuticular abaxial layer of the C. siliqua leaflet works as a sophisticated light and water management system: it reflects solar radiation diffusely to lower the surface temperature, and it has superhydrophobic character to keep the surface dry. Such attributes enable efficient gas exchange (photosynthesis and respiration), transpiration, and evaporation. To mimic for the first time the abaxial surface, a templation approach was adopted using poly(dimethylsiloxane) (PDMS)/poly(methylphenylsiloxane) (PMPS) positive/negative replicas and a soft polymer/siloxane negative replica produced by the sol-gel process. Because high topographical variations of the biotemplate and wax adhesion to the biohybrid film affected the replication quality, the reproduction of the wax texture via the synthesis of 1-octacosanol-grafted siloxane-based hybrid materials is proposed as a suitable route to duplicate the abaxial surface with high fidelity. The natural chemical/physical strategy adopted by the C. siliqua leaflet to face the harsh Mediterranean climate is a powerful source of bioinspiration for the development of diffuse reflecting and superhydrophobic material systems with foreseen applications as dual-functional antiglare and water-repelling coatings.
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| 33. |
- Silva, N. J. O., et al.
(author)
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Matrix assisted formation of ferrihydrite nanoparticles in a siloxane/poly(oxyethylene) nanohybrid
- 2005
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In: Journal of Materials Chemistry. - : Royal Society of Chemistry (RSC). - 1364-5501 .- 0959-9428. ; 15:4, s. 484-490
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Journal article (peer-reviewed)abstract
- Matrix-assisted formation of ferrihydrite, an iron oxide hydroxide analogue of the protein ferritin core, in a sol-gel derived organic-inorganic hybrid is reported. The hybrid network (named diureasil) is composed of poly(oxyethylene) chains of different average polymer molecular weights grafted to siloxane domains by means of urea cross-linkages and accommodates ferrihydrite nanoparticles. Magnetic measurements, Fourier transform infrared and nuclear magnetic resonance spectroscopy reveal that controlled modification of the polymer molecular weight allows the fine-tuning of the ability of the hybrid matrix to assist and promote iron coordination at the organic-inorganic interface and subsequent nucleation and growth of the ferrihydrite nanoparticles whose core size (2-4 nm) is tuned by the amount of iron incorporated. The polymer chain length, its arrangement and crystallinity, are key factors in the anchoring and formation of the ferrihydrite particles.
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| 34. |
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| 35. |
- van Kampen, A. M., et al.
(author)
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Boson-jet and jet-jet azimuthal correlations at high transverse momenta
- 2022
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In: Proceedings of Science. ; 414
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Conference paper (peer-reviewed)abstract
- We discuss our recent results on azimuthal distributions in vector boson + jets and multi-jet production at the LHC, obtained from the matching of next-to-leading order (NLO) perturbative matrix elements with transverse momentum dependent (TMD) parton branching. We present a comparative analysis of boson-jet and jet-jet correlations in the back-to-back region, and a study of the theoretical systematic uncertainties associated with the matching scale in the cases of TMD and collinear parton showers.
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| 36. |
- Yang, H., et al.
(author)
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Back-to-back azimuthal correlations in Z + jet events at high transverse momentum in the TMD parton branching method at next-to-leading order
- 2022
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In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 82:8
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Journal article (peer-reviewed)abstract
- Azimuthal correlations in Z + jet production at large transverse momenta are computed by matching Parton-Branching (PB) TMD parton distributions and showers with NLO calculations via MCatNLO. The predictions are compared with those for dijet production in the same kinematic range. The azimuthal correlations Δ ϕ between the Z boson and the leading jet are steeper compared to those in dijet production at transverse momenta O(100) GeV , while they become similar for very high transverse momenta O(1000) GeV . The different patterns of Z + jet and dijet azimuthal correlations can be used to search for potential factorization-breaking effects in the back-to-back region, which depend on the different color and spin structure of the final states and their interferences with the initial states. In order to investigate these effects experimentally, we propose to measure the ratio of the distributions in Δ ϕ for Z + jet- and multijet production at low and at high transverse momenta, and compare the results to predictions obtained assuming factorization. We examine the role of theoretical uncertainties by performing variations of the factorization scale, renormalization scale and matching scale. In particular, we present a comparative study of matching scale uncertainties in the cases of PB-TMD and collinear parton showers.
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| 37. |
- Aleksich, Mariya, et al.
(author)
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XFEL Microcrystallography of Self-Assembling Silver n-Alkanethiolates
- 2023
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In: Journal of the American Chemical Society. - 0002-7863. ; 145:31, s. 17042-17055
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Journal article (peer-reviewed)abstract
- New synthetic hybrid materials and their increasing complexity have placed growing demands on crystal growth for single-crystal X-ray diffraction analysis. Unfortunately, not all chemical systems are conducive to the isolation of single crystals for traditional characterization. Here, small-molecule serial femtosecond crystallography (smSFX) at atomic resolution (0.833 Å) is employed to characterize microcrystalline silver n-alkanethiolates with various alkyl chain lengths at X-ray free electron laser facilities, resolving long-standing controversies regarding the atomic connectivity and odd-even effects of layer stacking. smSFX provides high-quality crystal structures directly from the powder of the true unknowns, a capability that is particularly useful for systems having notoriously small or defective crystals. We present crystal structures of silver n-butanethiolate (C4), silver n-hexanethiolate (C6), and silver n-nonanethiolate (C9). We show that an odd-even effect originates from the orientation of the terminal methyl group and its role in packing efficiency. We also propose a secondary odd-even effect involving multiple mosaic blocks in the crystals containing even-numbered chains, identified by selected-area electron diffraction measurements. We conclude with a discussion of the merits of the synthetic preparation for the preparation of microdiffraction specimens and compare the long-range order in these crystals to that of self-assembled monolayers.
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| 38. |
- Balla, N. K., et al.
(author)
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Polarized Nonlinear Nanoscopy of Metal Nanostructures
- 2017
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In: ACS Photonics. - : American Chemical Society (ACS). - 2330-4022. ; 4:2, s. 292-301
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Journal article (peer-reviewed)abstract
- Nonlinear signals from metal nanostructures are known to be highly polarization-dependent, due to the intrinsic vectorial nature of nonlinear optical coupling. Nonlinear optical polarization responses contain important information on the near-field properties of nanostructures;, however, they remain complex to monitor and to model at the nanoscale. Polarization resolved nonlinear optical microscopy can potentially address this question; however, the recorded signals are generally averaged over the diffraction-limited size of a few hundreds of nanometers, thus, missing the spatial specificity of the nanostructure's optical response. Here we present a form of polarization resolved microscopy, named polarization nonlinear nanoscopy, which reveals subdiffraction scale vectorial variations of electromagnetic fields, even though the intensity image is diffraction-limited. We show that by exploiting, at a single subdiffraction pixel level, the information gained by the polarization-induced modulation, it is possible to spatially map the vectorial nature of plasmonic nonlinear optical interactions in nanostructures, revealing in particular surface contributions, retardation effects, and anisotropic spatial confinements.
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| 39. |
- Bermúdez Barón, Nicolás, et al.
(author)
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Among respiratory symptoms, wheeze associates most strongly with impaired lung function in adults with asthma: a long-term prospective cohort study
- 2021
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In: BMJ Open Respiratory Research. - : BMJ. - 2052-4439. ; 8:1
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Journal article (peer-reviewed)abstract
- Background Asthma is a common disease and a major public health concern. Respiratory symptoms are related to its prognosis, which in turn associates with lung function. Still this association on a long-term basis is not entirely understood. Aim To study the association of the type and number of respiratory symptoms with FEV1 and FEV1 decline in women and men with asthma. Method A population-based cohort of adults with asthma was examined at study entry between 1986 and 2001 and at follow-up between 2012 and 2014, and n=977 had valid measurements of FEV1 on both occasions. Data regarding respiratory symptoms at study entry (recurrent wheeze, dyspnoea, longstanding cough and productive cough) were analysed in relation to FEV1 and annual decline in FEV1, both unadjusted and adjusted for other potentially associated factors by linear regression. Results For both sexes recurrent wheeze and dyspnoea were associated with lower FEV1 at study entry and follow-up, while productive cough was associated with lower FEV1 only at follow-up. No associations were found between the type of symptoms and annual decline in FEV1. In adjusted analyses, the association between recurrent wheeze and lower FEV1 both at study entry and follow-up remained significant among women. Also, the association between a higher number of symptoms with lower FEV1 both at study entry and follow-up were present for both sexes and remained after adjustment. Conclusions Particularly recurrent wheeze and a higher number of respiratory symptoms may predict lower lung function also in the long run among women and men with asthma.
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| 40. |
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| 41. |
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| 42. |
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| 43. |
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| 44. |
- Cuquejo-Cid, A., et al.
(author)
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Anomalous and colossal thermal expansion, photoluminescence, and dielectric properties in lead halide-layered perovskites with cyclohexylammonium and cyclopentylammonium cations
- 2022
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In: iScience. - : Elsevier BV. - 2589-0042. ; 25:6, s. 104450-
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Journal article (peer-reviewed)abstract
- A detailed study of lead halide-layered perovskites with general formula A2PbX4 (where A is cyclohexylammonium (CHA) or cyclopentylammonium (CPA) cation and X is Cl− or Br− anion) is presented. Using variable temperature synchrotron X-ray powder diffraction, we observe that these compounds exhibit diverse crystal structures above room temperature. Very interestingly, we report some unconventional thermomechanical responses such as uniaxial negative thermal expansion and colossal positive thermal expansion in a perpendicular direction. For the polymorphs of (CHA)2PbBr4, the volumetric thermal expansion coefficient is among the highest reported for any extended inorganic crystalline solid, reaching 480 MK−1. The phase transitions are confirmed by calorimetry and dielectric measurements, where the dielectric versus temperature curves show anomalies related with the order-disorder phase transitions. In addition, these compounds exhibit a broad photoluminescence (PL) emission with a large Stokes shift, which is related with an exciton PL emission.
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| 45. |
- Goncalves, M. C., et al.
(author)
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Local structure and near-infrared emission features of neodymium-based amine functionalized organic/inorganic hybrids
- 2005
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In: Journal of Physical Chemistry B. - : American Chemical Society (ACS). - 1520-5207 .- 1520-6106. ; 109:43, s. 20093-20104
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Journal article (peer-reviewed)abstract
- Nd3+-based organic/inorganic hybrids have potential application in the field of integrated optics. Attractive sol-gel derived di-urea and di-urethane cross-linked poly (oxyethylene) (POE)/siloxane hybrids (di-ureasils and di-urethanesils, respectively) doped with neodymium triflate (Nd(CF3SO3)(3)) were examined by Fourier transform mid-infrared (FT-IR), Raman (FT-Raman), Si-29 magic-angle spinning (MAS) nuclear magnetic resonance (NMR) and photoluminescence spectroscopies, and small-angle X-ray scattering (SAXS). The goals of this work were to determine which cation coordinating site of the host matrix (ether oxygen atoms or carbonyl oxygen atoms) is active in each of the materials analyzed, its influence on the nanostructure of the samples and its relation with the photoluminescence properties. The main conclusion derived from this study is that the hydrogen-bonded associations formed throughout the materials play a major role in the hybrids nanostructure and photoluminescence properties.
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| 46. |
- Harkness, S, et al.
(author)
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Mixed methods in international collaborative research:: The experiences of the international study of parents, children, schools
- 2006
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In: CROSS-CULTURAL RESEARCH. - : SAGE Publications. - 1069-3971 .- 1552-3578. ; 40:1, s. 65-82
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Journal article (other academic/artistic)abstract
- The power of a mixed-methods approach combining anthropological and psychological theories and methods is demonstrated through the experiences of the International Study of Parents, Children, and Schools, a collaborative project involving teams of researchers from seven Western countries. The developmental niche framework of Super and Harkness proved useful for integrating multiple methods to understand the context of children’s early development at home and at school. Several parts of the study are presented as illustrations: the development and application of a common list of descriptors for coding parents’ discourse about their children; the construction of a derived etic form of a child temperament questionnaire; the discovery and exploration of ideas and practices related to parent-child co-sleeping; and the identification of cultural themes across various kinds of data. The authors conclude that a combination of anthropological and psychological methods can enrich understanding of children’s development in various cultural settings.
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| 47. |
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| 48. |
- Hui-Yuen, JS, et al.
(author)
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Safety and Efficacy of Belimumab to Treat Systemic Lupus Erythematosus in Academic Clinical Practices
- 2015
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In: The Journal of rheumatology. - : The Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 42:12, s. 2288-2295
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Journal article (peer-reviewed)abstract
- To evaluate the use and efficacy of belimumab in academic practices. Belimumab is a human monoclonal antibody that inhibits soluble B lymphocyte stimulator and has been approved for the treatment of adults with systemic lupus erythematosus (SLE).Methods.Invitations to participate and complete a 1-page questionnaire for each patient prescribed belimumab were sent to 16 physicians experienced in SLE phase III clinical trials. The outcome was defined as the physician’s impression of improvement in the initial manifestation(s) being treated without worsening in other organ systems.Results.Of 195 patients treated with belimumab at 10 academic centers, 96% were taking background medications for SLE at initiation of belimumab, with 74% taking corticosteroids. The main indications for initiation of belimumab were arthritis, rash, and/or worsening serologic activity, with 30% of patients unable to taper corticosteroids. Of the 120 patients taking belimumab for at least 6 months, 51% responded clinically and 67% had ≥ 25% improvement in laboratory values. While numbers are limited, black patients showed improvement at 6 months. In a subset of 39 patients with childhood-onset SLE, 65% responded favorably at 6 months, and 35% discontinued corticosteroids.Conclusion.Our data demonstrate favorable clinical and laboratory outcomes in patients with SLE at 6 months across all racial and ethnic groups, with similar improvement seen among patients with childhood-onset SLE.
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| 49. |
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| 50. |
- López, A., et al.
(author)
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Laboratory characterization and astrophysical detection of vibrationally excited states of vinyl cyanide in Orion-KL
- 2014
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 572
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Journal article (peer-reviewed)abstract
- Context. We perform a laboratory characterization in the 18–1893 GHz range and astronomical detection between 80–280 GHz in Orion-KL with IRAM-30 m of CH2CHCN (vinyl cyanide) in its ground and vibrationally excited states. Aims. Our aim is to improve the understanding of rotational spectra of vibrationally excited vinyl cyanide with new laboratory data and analysis. The laboratory results allow searching for these excited state transitions in the Orion-KL line survey. Furthermore, rotational lines of CH2CHCN contribute to the understanding of the physical and chemical properties of the cloud. Methods. Laboratory measurements of CH2CHCN made on several different frequency-modulated spectrometers were combined into a single broadband 50–1900 GHz spectrum and its assignment was confirmed by Stark modulation spectra recorded in the 18–40 GHz region and by ab-initio anharmonic force field calculations. For analyzing the emission lines of vinyl cyanide detected in Orion-KL we used the excitation and radiative transfer code (MADEX) at LTE conditions. Results. Detailed characterization of laboratory spectra of CH2CHCN in nine different excited vibrational states: ?11 = 1, ?15 = 1, 2) ⇔ (?10 = 1,?15 = 1) ⇔ (?11 = 1,?14 = 1), and ?11 = 4 are determined, as well as the detection of transitions in the ?11 = 2and ?11 = 2, ?10 = 1 ⇔ (?11 = 1,?15 = 1), ?11 = 3/?15 = 2/?14 = 1, (?11 = 1,?10 = 1) ⇔ (?11 = 2,?15 = 1), ?9 = 1, (?11 = 1,?15 = The rotational transitions of the ground state of this molecule emerge from four cloud components of hot core nature, which trace the ?11 = 3 states for the first time in Orion-KL and of those in the ?10 = 1 ⇔ (?11 = 1,?15 = 1) dyad of states for the first time in space. physical and chemical conditions of high mass star forming regions in the Orion-KL Nebula. The lowest energy vibrationally excited states of vinyl cyanide, such as ?11 = 1 (at 328.5 K), ?15 = 1 (at 478.6 K), ?11 = 2 (at 657.8 K), the ?10 = 1 ⇔ (?11 = 1,?15 = 1) dyad (at 806.4/809.9 K), and ?11 = 3 (at 987.9 K), are populated under warm and dense conditions, so they probe the hottest parts of the Orion-KL source. The vibrational temperatures derived for the ?11 = 1, ?11 = 2, and ?15 = 1 states are 252 ± 76K, 242 ± 121K, column density of CH2CHCN in the ground state is (3.0 ± 0.9) × 1015 cm−2. We report the detection of methyl isocyanide (CH3NC) and 227 ± 68K, respectively; all of them are close to the mean kinetic temperature of the hot core component (210K). The total for the first time in Orion-KL and a tentative detection of vinyl isocyanide (CH2CHNC). We also give column density ratios between the cyanide and isocyanide isomers, obtaining a N(CH3NC)/N(CH3CN) ratio of 0.002. Conclusions. Laboratory characterization of many previously unassigned vibrationally excited states of vinyl cyanide ranging from microwave to THz frequencies allowed us to detect these molecular species in Orion-KL. Column density, rotational and vibrational temperatures for CH2CHCN in their ground and excited states, and the isotopologues have been constrained by means of a sample of more than 1000 lines in this survey.
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