87 research outputs found

    Consolidations and the Sequence of Acquisitions to Monopoly

    Get PDF
    We examine horizontal merger activity between firms which have differing costs. Upon merging owners can transfer technology to an acquired firm and can decide whether to operate their firms as separate entities in the product market or consolidate their acquisitions. Thus, in our analysis, mergers can exhibit both an efficiency effect and a market power effect. The purchase prices of target firms are determined via a bargaining game. We find that the largest firm is likely to be acquisitive and that the optimal sequence of mergers entails targeting the next largest rival firm. We find that not consolidating an acquired firm can reveal the intention to acquire additional firms. The optimal sequence of mergers with technology transfers and no consolidations is found initially to be welfare improving. Ultimately, however, the acquisitions lead to consolidation and a decrease in total welfare. ZUSAMMENFASSUNG - (Konsolidierungen und die Folge von Akquisitionen zum Monopol) In dem Beitrag werden horizontale UnternehmenszusammenschlĂŒsse zwischen Unternehmen mit unterschiedlichen Kosten analysiert. FĂŒr das erwerbende Unternehmen stellt sich die Frage, ob es Technologie zu einer erworbenen Firma transferieren sollte und, ob es das erworbene Unternehmen als getrennte Einheit im Produktmarkt betreiben oder mit dem fusionierten Unternehmen zusammen am Markt operieren will. In der Analyse wird der Effizienzeffekt und der Marktmachteffekt berĂŒcksichtigt. Der Kaufpreis des zu erwerbenden Unternehmens wird in einem "bargaining game" ermittelt. Im Ergebnis zeigt sich, daß das grĂ¶ĂŸte Unternehmen wahrscheinlich das erwerbende sein wird und daß die optimale Reihenfolge von Fusionen sich auf das nĂ€chst grĂ¶ĂŸte Konkurrenzunternehmen bezieht. Außerdem zeigt sich, daß die Nichtkonsolidierung mit erworbenen Unternehmen daraufhin deutet, daß eine Intention zum Erwerb weiterer Firmen vorliegt. Die optimale Folge von Fusionen mit Technologietransfer und ohne Konsolidierungen erhöht anfangs die Wohlfahrt. Letztlich aber fĂŒhren die Erwerbungen zur Konsolidierung und zu einem Absinken der Gesamtwohlfahrt.

    The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. IV. Unveiling the Embedded Intermediate-Mass Protostar and Disk within OMC2-FIR3/HOPS-370

    Get PDF
    We present ALMA (0.87 and 1.3 mm) and VLA (9 mm) observations toward the candidate intermediate-mass protostar OMC2-FIR3 (HOPS-370; L_(bol) ~ 314 L_⊙) at ~0."1 (40 au) resolution for the continuum emission and ~0."25 (100 au) resolution of nine molecular lines. The dust continuum observed with ALMA at 0.87 and 1.3 mm resolves a near edge-on disk toward HOPS-370 with an apparent radius of ~100 au. The VLA observations detect both the disk in dust continuum and free–free emission extended along the jet direction. The ALMA observations of molecular lines (H₂CO, SO, CH₃OH, ÂčÂłCO, CÂč⁞O, NS, and HÂčÂłCN) reveal rotation of the apparent disk surrounding HOPS-370 orthogonal to the jet/outflow direction. We fit radiative transfer models to both the dust continuum structure of the disk and molecular line kinematics of the inner envelope and disk for the H₂CO, CH₃OH, NS, and SO lines. The central protostar mass is determined to be ~2.5 M_⊙ with a disk radius of ~94 au, when fit using combinations of the H₂CO, CH₃OH, NS, and SO lines, consistent with an intermediate-mass protostar. Modeling of the dust continuum and spectral energy distribution yields a disk mass of 0.035 M_⊙ (inferred dust+gas) and a dust disk radius of 62 au; thus, the dust disk may have a smaller radius than the gas disk, similar to Class II disks. In order to explain the observed luminosity with the measured protostar mass, HOPS-370 must be accreting at a rate of (1.7−3.2) × 10⁻⁔ M_⊙ yr⁻Âč

    The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. I. Identifying and Characterizing the Protostellar Content of the OMC-2 FIR4 and OMC-2 FIR3 Regions

    Get PDF
    We present ALMA (0.87~mm) and VLA (9~mm) observations toward OMC2-FIR4 and OMC2-FIR3 within the Orion integral-shaped filament that are thought to be the nearest regions of intermediate mass star formation. We characterize the continuum sources within these regions on ∌\sim40~AU (0\farcs1) scales and associated molecular line emission at a factor of ∌\sim30 better resolution than previous observations at similar wavelengths. We identify six compact continuum sources within OMC2-FIR4, four in OMC2-FIR3, and one additional source just outside OMC2-FIR4. This continuum emission is tracing the inner envelope and/or disk emission on less than 100~AU scales. HOPS-108 is the only protostar in OMC2-FIR4 that exhibits emission from high-excitation transitions of complex organic molecules (e.g., methanol and other lines) coincident with the continuum emission. HOPS-370 in OMC2-FIR3 with L~∌\sim~360~\lsun, also exhibits emission from high-excitation methanol and other lines. The methanol emission toward these two protostars is indicative of temperatures high enough to thermally evaporate methanol from icy dust grains; overall these protostars have characteristics similar to hot corinos. We do not identify a clear outflow from HOPS-108 in \twco, but find evidence of interaction between the outflow/jet from HOPS-370 and the OMC2-FIR4 region. The multitude of observational constraints indicate that HOPS-108 is likely a low to intermediate-mass protostar in its main mass accretion phase and it is the most luminous protostar in OMC2-FIR4. The high resolution data presented here are essential for disentangling the embedded protostars from their surrounding dusty environments and characterizing them

    Evaluation of the functional efficacy of an antioxidative probiotic in healthy volunteers

    Get PDF
    BACKGROUND: In persons without clinical symptom it is difficult to assess an impact of probiotics regarding its effect on health. We evaluated the functional efficacy of the probiotic Lactobacillus fermentum ME-3 in healthy volunteers by measuring the influence of two different formulations on intestinal lactoflora, fecal recovery of the probiotic strain and oxidative stress markers of blood and urine after 3 weeks consumption. METHODS: Two 3-week healthy volunteer trials were performed. Open placebo controlled (OPC) study participants (n = 21) consumed either goat milk or by L. fermentum ME-3 fermented goat milk (daily dose 11.8 log CFU (Colony Forming Units). Double blind randomised placebo controlled (DBRP) study participants (n = 24) received either capsules with L. fermentum ME-3 (daily of dose 9.2 CFU) or placebo capsules. The faecal lactoflora composition, faecal ME-3 recovery, effect of the consumption on intestinal lactoflora, and oxidative stress markers of blood (total antioxidative activity; total antioxidative status and glutathione red-ox ratio) was measured. RESULTS: ME-3 was well tolerated and a significant increase in total faecal lactobacilli yet no predominance of ME-3 was detected in all study groups. Faecal recovery of ME-3 was documented by molecular methods only in fermented milk group, however the significant improvement of blood TAA (Total Antioxidative Activity) and TAS (Total Antioxidative Status) indices was seen both in case of fermented goat milk and capsules", yet glutathione re-ox ratio values decreased only in case of fermented by ME-3 goat milk. CONCLUSION: The functional efficacy of both consumed formulations of an antioxidative probiotic L. fermentum ME-3 is proved by the increase of the intestinal lactobacilli counts providing putative defence against enteric infections and by reduction of the oxidative stress indices of blood and urine of healthy volunteers. In non-diseased host the probiotic health claims can be assessed by improvement of some measurable laboratory indices of well-established physiological functions of host, e.g. markers of antioxidative defence system

    Exocomets from a Solar System Perspective

    Get PDF
    Exocomets are small bodies releasing gas and dust which orbit stars other than the Sun. Their existence was first inferred from the detection of variable absorption features in stellar spectra in the late 1980s using spectroscopy. More recently, they have been detected through photometric transits from space, and through far-IR/mm gas emission within debris disks. As (exo)comets are considered to contain the most pristine material accessible in stellar systems, they hold the potential to give us information about early stage formation and evolution conditions of extra Solar Systems. In the Solar System, comets carry the physical and chemical memory of the protoplanetary disk environment where they formed, providing relevant information on processes in the primordial solar nebula. The aim of this paper is to compare essential compositional properties between Solar System comets and exocomets. The paper aims to highlight commonalities and to discuss differences which may aid the communication between the involved research communities and perhaps also avoid misconceptions. Exocomets likely vary in their composition depending on their formation environment like Solar System comets do, and since exocomets are not resolved spatially, they pose a challenge when comparing them to high fidelity observations of Solar System comets. Observations of gas around main sequence stars, spectroscopic observations of "polluted" white dwarf atmospheres and spectroscopic observations of transiting exocomets suggest that exocomets may show compositional similarities with Solar System comets. The recent interstellar visitor 2I/Borisov showed gas, dust and nuclear properties similar to that of Solar System comets. This raises the tantalising prospect that observations of interstellar comets may help bridge the fields of exocomet and Solar System comets.Comment: 25 pages, 3 figures. To be published in PASP. This paper is the product of a workshop at the Lorentz Centre in Leiden, the Netherland

    MARSTRUCT benchmark study on nonlinear FE simulation of an experiment of an indenter impact with a ship side-shell structure

    Get PDF
    This paper presents a benchmark study on collision simulations that was initiated by the MARSTRUCT Virtual Institute. The objective was to compare assumptions, finite element models, modelling techniques and experiences between established researchers within the field. Fifteen research groups world-wide participated in the study. An experiment involving a rigid indenter penetrating a ship-like side structure was used as the case study. A description of how the experiment was performed, the geometry model of it, and material properties were distributed to the participants prior to their simulations. The paper presents the results obtained from the fifteen FE simulations and the experiment. It presents a comparison of, among other factors, the reaction force versus the indenter displacement, internal energy absorbed by the structure versus the indenter displacement, and analyses of the participants' ability to predict failure modes and events that were observed in the experiment. The outcome of the study is a discussion and recommendations regarding mesh size, failure criteria and damage models, interpretation of material data and how they are used in a constitutive material model, and finally, uncertainties in general

    Enabling planetary science across light-years. Ariel Definition Study Report

    Get PDF
    Ariel, the Atmospheric Remote-sensing Infrared Exoplanet Large-survey, was adopted as the fourth medium-class mission in ESA's Cosmic Vision programme to be launched in 2029. During its 4-year mission, Ariel will study what exoplanets are made of, how they formed and how they evolve, by surveying a diverse sample of about 1000 extrasolar planets, simultaneously in visible and infrared wavelengths. It is the first mission dedicated to measuring the chemical composition and thermal structures of hundreds of transiting exoplanets, enabling planetary science far beyond the boundaries of the Solar System. The payload consists of an off-axis Cassegrain telescope (primary mirror 1100 mm x 730 mm ellipse) and two separate instruments (FGS and AIRS) covering simultaneously 0.5-7.8 micron spectral range. The satellite is best placed into an L2 orbit to maximise the thermal stability and the field of regard. The payload module is passively cooled via a series of V-Groove radiators; the detectors for the AIRS are the only items that require active cooling via an active Ne JT cooler. The Ariel payload is developed by a consortium of more than 50 institutes from 16 ESA countries, which include the UK, France, Italy, Belgium, Poland, Spain, Austria, Denmark, Ireland, Portugal, Czech Republic, Hungary, the Netherlands, Sweden, Norway, Estonia, and a NASA contribution
    • 

    corecore