Outflows of hot molecular gas in ultra-luminous infra-red galaxies mapped with VLT-SINFONI

We present the detection and morphological characterization of hot molecular gas outflows in nearby ultra-luminous infrared galaxies, using the near-IR integral-field spectrograph SINFONI on the VLT. We detect outflows observed in the 2.12 micron H$_{2}$ 1-0 S(1) line for three out of four ULIRGs analyzed; IRAS 12112+0305, 14348-1447, and 22491-1808. The outflows are mapped on scales of 0.7-1.6 kpc, show typical outflow velocities of 300-500 km/s, and appear to originate from the nuclear region. The outflows comprise hot molecular gas masses of ~6-8x10$^3$ M(sun). Assuming a hot-to-cold molecular gas mass ratio of 6x10$^{-5}$, as found in nearby luminous IR galaxies, the total (hot+cold) molecular gas mass in these outflows is expected to be ~1x10$^{8}$ M(sun). This translates into molecular mass outflow rates of ~30-85 M(sun)/yr, which is a factor of a few lower than the star formation rate in these ULIRGs. In addition, most of the outflowing molecular gas does not reach the escape velocity of these merger systems, which implies that the bulk of the outflowing molecular gas is re-distributed within the system and thus remains available for future star formation. The fastest H$_{2}$ outflow is seen in the Compton-thick AGN of IRAS 14348-1447, reaching a maximum outflow velocity of ~900 km/s. Another ULIRG, IRAS 17208-0014, shows asymmetric H$_{2}$ line profiles different from the outflows seen in the other three ULIRGs. We discuss several alternative explanations for its line asymmetries, including a very gentle galactic wind, internal gas dynamics, low-velocity gas outside the disk, or two superposed gas disks. We do not detect the hot molecular counterpart to the outflow previously detected in CO(2-1) in IRAS 17208-0014, but we note that our SINFONI data are not sensitive enough to detect this outflow if it has a small hot-to-cold molecular gas mass ratio of < 9x10$^{-6}$.Comment: Accepted for publication in A&A (11 pages, 10 figures

Ectoparasitosis por ácaro de la cosecha

Se describe la parasitación en perro por Neotrombícula autumnalú (ácaro de la cosecha) en cuatro casos clínicos.We describe four clinical cases of parasitic disease in dogs caused by Neotrombicula autumnalis (Harvest Chigger)

Theoretical study of the effect of substituent and backbone conformation on the electronic properties of symmetrically substituted poly(di‐n‐alkylsilanes)

We present the results of ab initio 3‐21G∗ geometry optimizations and valence effective Hamiltonian (VEH) band structure calculations aimed at determining the evolution of the geometric and electronic (ionization potential, electron affinities, and band gaps) properties of all‐trans poly(dimethylsilane), poly(diethylsilane), poly(di‐n‐propylsilane), and poly(di‐n‐butylsilane) when increasing the size of the alkyl group. In the latter polymer, we have also studied the 7/3 conformation, in order to analyze the effect of the backbone conformation on the geometric and electronic structure. The VEH ionization potentials of all‐trans poly(di‐n‐alkylsilanes) are almost equal, and as experimental photoemission data show, only slight differences are appreciated. The band gap decreases in going from poly(di‐n‐butylsilane) to poly(di‐n‐propylsilane) and to poly(diethylsilane), and increases when passing to poly(dimethylsilane), which coincides with experimental evidences on poly(di‐n‐alkylsilanes). The change from all‐trans to 7/3 conformation of poly(di‐n‐butylsilane) implies an increase of both, ionization potential and band gap, in perfect agreement with experimental photoemission and absorption data. The applicability of VEH to deal with poly(di‐n‐alkylsilanes) is [email protected]

Study of pinholes and nanotubes in AlInGaN films by cathodoluminescence and atomic force microscopy

Cathodoluminescence (CL) in the scanning electron microscope and atomic force microscopy (AFM) have been used to study the formation of pinholes in tensile and compressively strained AlInGaN films grown on Al2O3 substrates by plasma-induced molecular beam epitaxy. Nanotubes, pits, and V-shaped pinholes are observed in a tensile strained sample. CL images show an enhanced emission around the pits and a lower intensity at the V-shaped pinholes. Rounded pinholes appear in compressively strained samples in island-like regions with higher In concentration. The grain structure near the pinholes is resolved by AFM. (C) 2004 American Institute of Physics

Assessment of acoustic reciprocity and conservativeness in exhaust aftertreatment systems

[EN] Tightening emission standards limiting gas and aerosol emissions from internal combustion engines have led to the extensive use of exhaust aftertreatment systems (EATS) with different chemical functions as a solution to meet standards requirements. Incidentally, the placement of aftertreatment monolithic devices into the exhaust line also plays a key role on the exhaust noise emission. Their presence disturbs the pattern of the pressure waves and sets the boundary conditions for the silencer design. The impact of the EATS on wave transmission can be analyzed by means of the transmission or scattering matrix. The present work discusses the implications of acoustic reciprocity and conservativeness on the definition of the scattering matrix elements. The fulfillment of these properties in real operating conditions was evaluated against a set of experimental data obtained for several exhaust aftertreatment monolithic bricks in an impulse test rig. The influence of different excitation amplitudes and superimposed mean flows was also considered. Once it was shown that the devices are reciprocal, the need to account for dissipation phenomena was evidenced. Finally, the application of reciprocity and conservativeness together with dissipation provided simple expressions allowing to predict the response of the EATS in the inverse direction, i.e. from outlet to inlet, from the transmission and reflection properties obtained in the direct direction. Thus, the proposed procedure becomes useful to reduce both the required number of tests and the gas dynamics modelling work in methodologies driven to assess the acoustic response of EATS based on the use of experimental and computational tools. (C) 2018 Elsevier Ltd. All rights reserved.This research has been partially supported by FEDER and the Government of Spain through project TRA2016-79185-R. Additionally, the Ph.D. student Enrique José Sanchis has been funded by a grant from Universitat Politècnica de València with reference FPI-2016-S2-1355.Torregrosa, AJ.; Piqueras, P.; Sanchis-Pacheco, EJ.; Guilain, S.; Dubarry, M. (2018). Assessment of acoustic reciprocity and conservativeness in exhaust aftertreatment systems. Journal of Sound and Vibration. 436:46-61. https://doi.org/10.1016/j.jsv.2018.08.032S466143

Effects of Including a Penetration Test in Motorcyclist Helmet Standards: Influence on Helmet Stiffness and Impact Performance

Regulation ECE-22.05/06 does not require a helmet penetration test. Penetration testing is controversial since it has been shown that it may cause the helmet to behave in a non-desirable stiff way in real-world crashes. This study aimed to assess the effect of the penetration test in the impact performance of helmets. Twenty full-face motorcycle helmets were penetration tested at multiple locations of the helmet shell. Then, 10 helmets were selected and split into two groups (hard shell and soft shell) depending on the results of the penetration tests. These 10 helmets were then drop tested at front, lateral, and top areas at two different impact speeds (5 m/s and 8.2 m/s) to assess their impact performance against head injuries. The statistical analyses did not show any significant difference between the two groups (hard/soft shell) at 5 m/s. Similar results were observed at 8.2 m/s, except for the top area of the helmet in which the peak linear acceleration was significantly higher for the soft shell group than for the hard shell group (230 ± 12 g vs. 211 ± 11 g; p-value = 0.038). The results of this study suggest that a stiffer shell does not necessarily cause helmets to behave in a stiffer way when striking rigid flat surfaces. These experiments also showed that hard shell helmets can provide better protection at higher impact speeds without damaging helmet performance at lower impact speeds. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Luminescence study of thermal treated and laser irradiated Bi_12GeO_20 and Bi_12SiO_20 crystals

Changes on the defect structure of Bi12GeO20 (BGO) and Bi12SiO20 (BSO) crystals induced by thermal treatments and laser irradiation have been studied by means of cathodoluminescence in the scanning electron microscope. The results have been compared to those previously reported for untreated and electron irradiated samples and recombination mechanisms responsible for some of the observed luminescence bands are discussed. Annealing of EGO samples causes the appearance of a new luminescence band at about 390 nm. The centers responsible for this band decorate the deformation slip bands in quenched EGO as observed in the cathodoluminescence images. The emission observed in BSO in the same spectral range is quenched during the annealing treatment. The annealing induced reduction of Bi ions to metallic Bi appears to be related to the quenching of a band at 640 nm observed in untreated samples

Navigating tensions in inclusive conservation: Learning from the Utrechtse Heuvelrug National Park in the Netherlands

Inclusive conservation is promoted as a means to integrate stakeholders in nature, conservation. Despite several studies recognizing that inclusive conservation of protected areas may be challenging and requires explicitly addressing potential tensions between stakeholders, little research has unpacked how these tensions manifest in specific contexts. This paper aims to explore possible approaches for navigating tensions to improve the facilitation of an inclusive conservation approach in the Utrechtse Heuvelrug National Park in the Netherlands. We conducted 18 semistructured interviews with stakeholders such as public and private landowners and, municipal and provincial governments in the national park. Results reveal a longer history of collaboration which still fails to address the root of the tensions. The experiences show that compromising or consensus building amongst stakeholders alone is not sufficient for achieving inclusive conservation. Guidance and clear goals set by policy, as well as sufficient investments in capacity and trust building are recommended to avoid inaction. Furthermore, we found that tensions are inextricably linked to different dimensions of power, such as discursive and structural power. While considering power in inclusive conservation can provide a realistic perspective we also, acknowledge that equalizing power is not the silver bullet underpinning this conservation approach.</p

Large Deformation Effects in the N = Z 44Ti Compound Nucleus

The N = Z 44Ti* nucleus has been populated in Fusion Evaporation process at very high excitation energies and angular momenta using two entrance channels with different mass-asymmetry. The deformation effects in the rapidly rotating nuclei have been investigated through the energy distribution of the alpha-particle combined to statistical-model calculations. In the case of low-multiplicity events, the ratio between first particle emitted has been measured and shows significant disagreement with the predictions of the statistical-model. This may explain The large discrepancies observed in proton energy spectra measured in previous experiments performed in the same mass region.Comment: Proceeding of the 10th International Conference on Nuclear Reaction Mechanisms, Varenna Italy, June 9-13 2003. 10 pages, 6 figures, 1 tabl