2,070 research outputs found

    A generation-oriented workbench for performance grammar: Capturing linear order variability in German and Dutch

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    We describe a generation-oriented workbench for the Performance Grammar (PG) formalism, highlighting the treatment of certain word order and movement constraints in Dutch and German. PG enables a simple and uniform treatment of a heterogeneous collection of linear order phenomena in the domain of verb constructions (variably known as Cross-serial Dependencies, Verb Raising, Clause Union, Extraposition, Third Construction, Particle Hopping, etc.). The central data structures enabling this feature are clausal “topologies”: one-dimensional arrays associated with clauses, whose cells (“slots”) provide landing sites for the constituents of the clause. Movement operations are enabled by unification of lateral slots of topologies at adjacent levels of the clause hierarchy. The PGW generator assists the grammar developer in testing whether the implemented syntactic knowledge allows all and only the well-formed permutations of constituents

    A generation-oriented workbench for performance grammar: Capturing linear order variability in German and Dutch

    Get PDF
    We describe a generation-oriented workbench for the Performance Grammar (PG) formalism, highlighting the treatment of certain word order and movement constraints in Dutch and German. PG enables a simple and uniform treatment of a heterogeneous collection of linear order phenomena in the domain of verb constructions (variably known as Cross-serial Dependencies, Verb Raising, Clause Union, Extraposition, Third Construction, Particle Hopping, etc.). The central data structures enabling this feature are clausal “topologies”: one-dimensional arrays associated with clauses, whose cells (“slots”) provide landing sites for the constituents of the clause. Movement operations are enabled by unification of lateral slots of topologies at adjacent levels of the clause hierarchy. The PGW generator assists the grammar developer in testing whether the implemented syntactic knowledge allows all and only the well-formed permutations of constituents

    The origin of organic emission in NGC 2071

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    Context: The physical origin behind organic emission in embedded low-mass star formation has been fiercely debated in the last two decades. A multitude of scenarios have been proposed, from a hot corino to PDRs on cavity walls to shock excitation. Aims: The aim of this paper is to determine the location and the corresponding physical conditions of the gas responsible for organics emission lines. The outflows around the small protocluster NGC 2071 are an ideal testbed to differentiate between various scenarios. Methods: Using Herschel-HIFI and the SMA, observations of CH3OH, H2CO and CH3CN emission lines over a wide range of excitation energies were obtained. Comparisons to a grid of radiative transfer models provide constraints on the physical conditions. Comparison to H2O line shape is able to trace gas-phase synthesis versus a sputtered origin. Results: Emission of organics originates in three spots: the continuum sources IRS 1 ('B') and IRS 3 ('A') as well as a outflow position ('F'). Densities are above 107^7 cm−3^{-3} and temperatures between 100 to 200 K. CH3OH emission observed with HIFI originates in all three regions and cannot be associated with a single region. Very little organic emission originates outside of these regions. Conclusions: Although the three regions are small (<1,500 AU), gas-phase organics likely originate from sputtering of ices due to outflow activity. The derived high densities (>107^7 cm−3^{-3}) are likely a requirement for organic molecules to survive from being destroyed by shock products. The lack of spatially extended emission confirms that organic molecules cannot (re)form through gas-phase synthesis, as opposed to H2O, which shows strong line wing emission. The lack of CH3CN emission at 'F' is evidence for a different history of ice processing due to the absence of a protostar at that location and recent ice mantle evaporation.Comment: 10 Pages, 8 figures, Accepted for Astronomy and Astrophysic

    Hydrogels by irradiation of a synthetic heparinoid polyelectrolyte

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    Gamma irradiation of aqueous solutions of a synthetic heparinoid polyelectrolyte results in the formation of hydrogels, varying in water content and mechanical strength. The equilibrium water content and the mechanical strength of the hydrogels are dependent on the initial polyelectrolyte concentration, the molecular weight of the polyelectrolyte, the percentage of double bonds in the polyelectrolyte and the radiation dose.\ud \ud The polyelectrolyte hydrogels do not deplete Antithrombin III from blood and there is no activation of factor XII according to an in vitro kallikrein generation test. However, in a very sensitive test for factor XII activation (contact promoted shortening of the thrombotest) a slight activation of this factor was observed

    Radio-Frequency Spectroscopy of Ultracold Fermions

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    Radio-frequency techniques were used to study ultracold fermions. We observed the absence of mean-field "clock" shifts, the dominant source of systematic error in current atomic clocks based on bosonic atoms. This is a direct consequence of fermionic antisymmetry. Resonance shifts proportional to interaction strengths were observed in a three-level system. However, in the strongly interacting regime, these shifts became very small, reflecting the quantum unitarity limit and many-body effects. This insight into an interacting Fermi gas is relevant for the quest to observe superfluidity in this system.Comment: 6 pages, 6 figure

    Feshbach Spectroscopy of a Shape Resonance

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    We present a new spectroscopy technique for studying cold-collision properties. The technique is based on the association and dissociation of ultracold molecules using a magnetically tunable Feshbach resonance. The energy and lifetime of a shape resonance are determined from a measurement of the dissociation rate. Additional spectroscopic information is obtained from the observation of a spatial interference pattern between an outgoing s wave and d wave. The experimental data agree well with the results from a new model, in which the dissociation process is connected to a scattering gedanken experiment, which is analyzed using a coupled-channels calculation.Comment: Introduction rewritte

    Phobie, Fantasie und Fetisch? Antimuslimischer Rassismus und Sexismus in pornografischen Filmen

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    Dieses Working Paper untersucht 14 ausgewĂ€hlte pornographische Filme auf ihre sexistischen und anti-muslimisch rassistischen Inhalte. Diese Filme sind unter anderem als Refugee- oder Hijab-Pornos bekannt und zeigen bis auf ein Kopftuch nackte Darsteller*innen beim Sex mit (hĂ€ufig) weißen (Cis-)MĂ€nnern. Im Laufe der Anayse soll das pornographische Medium selbst nicht verurteilt, sondern als hilfreiche Linse behandelt werden, durch die etwas ĂŒber UnterdrĂŒckungs- und Machtmechanismen erfahren werden kann. Es ermöglicht, das koloniale Blickregime bezĂŒglich der verschleierten Muslima offenzulegen. Das umfasst sowohl das panoptische BedĂŒrfnis nach ihrer EntblĂ¶ĂŸung auf der Suche nach einer zu entdeckenden Wahrheit als auch ihre Fetischisierung ĂŒber ihre angenommene Andersartigkeit und PrĂŒderie. Auf ihre Verschleierung und "Fremdheit" wird wiederum mit Gewalt und Dominanzverhalten vonseiten ihres sexuellen GegenĂŒbers reagiert.This Working Paper investigates 14 selected porno graphic films and their anti-Muslim, racist, and sexist content. These films are mostly known under the title of Refugee- or Hijab-Porn and show actresses wearing nothing but a veil having sex with (mostly) white (cis-)men. In the process of this analysis, the pornographic medium itself shall not be condemned, but rather taken as a useful lens through which one can learn about mechanisms of oppression. It makes it possible to take a closer look at the continuity of the colonial gaze in relation to the veiled Muslim woman. This includes the desire to know all, to undress her, always looking for a truth waiting to be discovered, as well as the fetishization of Muslim female bodies based on their “Other ness” and prudery. Her being veiled and her "foreignness" are then met with dominating behaviour and violence on the part of her on-screen sexual counterpart

    The hot core towards the intermediate mass protostar NGC7129 FIRS 2: Chemical similarities with Orion KL

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    NGC 7129 FIRS 2 (hereafter FIRS 2) is an intermediate-mass (2 to 8 Msun) protostar located at a distance of 1250 pc. High spatial resolution observations are required to resolve the hot core at its center. We present a molecular survey from 218200 MHz to 221800 MHz carried out with the IRAM Plateau de Bure Interferometer. These observations were complemented with a long integration single-dish spectrum taken with the IRAM 30m telescope. We used a Local Thermodynamic Equilibrium (LTE) single temperature code to model the whole dataset. The interferometric spectrum is crowded with a total of ~300 lines from which a few dozens remain unidentified yet. The spectrum has been modeled with a total of 20 species and their isomers, isotopologues and deuterated compounds. Complex molecules like methyl formate (CH3OCHO), ethanol (CH3CH2OH), glycolaldehyde (CH2OHCHO), acetone (CH3COCH3), dimethyl ether (CH3OCH3), ethyl cyanide (CH3CH2CN) and the aGg' conformer of ethylene glycol (aGg'-(CH2OH)_2) are among the detected species. The detection of vibrationally excited lines of CH3CN, CH3OCHO, CH3OH, OCS, HC3N and CH3CHO proves the existence of gas and dust at high temperatures. In fact, the gas kinetic temperature estimated from the vibrational lines of CH3CN, ~405 K, is similar to that measured in massive hot cores. Our data allow an extensive comparison of the chemistry in FIRS~2 and the Orion hot core. We find a quite similar chemistry in FIRS 2 and Orion. Most of the studied fractional molecular abundances agree within a factor of 5. Larger differences are only found for the deuterated compounds D2CO and CH2DOH and a few molecules (CH3CH2CN, SO2, HNCO and CH3CHO). Since the physical conditions are similar in both hot cores, only different initial conditions (warmer pre-collapse phase in the case of Orion) and/or different crossing time of the gas in the hot core can explain this behavior.Comment: 30 pages, 9 figure
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