6,883 research outputs found

    Distance, structure and bright stellar content of the dwarf irregular galaxy UGC 685

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    B,R, and J frames taken with the Calar Alto 3.5m telescope of the dwarf irregular galaxy UGC 685 are presented. The brightest part of the stellar population is resolved in B and R, very few also in J. The stellar color-magnitude diagram is discussed. An estimate of the distance to UGC 685 of 5.5 Mpc is derived based on the brightest blue supergiant stars. Most of the resolved bright stars show colors in the range −0.1≀B−R≀+0.7-0.1 \le B-R \le +0.7. The continuum light of the unresolved stars is distributed rather regular in B, R, and J, showing only minor irregularities. This surface brightness distribution follows an exponential law in all three colors with a scale length rc=0.33r_c = 0.33 kpc. The central surface brightnesses are 21.57±0.09mag/□â€Čâ€Č21.57 \pm 0.09 mag/\Box'', 20.65±0.06mag/□â€Čâ€Č20.65 \pm 0.06mag/\Box'', and 20.11±0.11mag/□â€Čâ€Č20.11 \pm 0.11 mag/\Box'', in B, R, and J, respectively. The surface brightness can be traced out to 5 rcr_c in B and R. Thus, UGC 685 belongs to the class of dwarfs where the HI distribution is much more extended (here 2.6 times) than the optical (stellar) light distribution, but contrary to many objects of this type, it does not belong to the class of low-surface brightness objects. The overall colors are B−R=+0.97B-R = + 0.97, B−J=+1.55B-J = +1.55 and the magnitude is B = 14.55 (MBoM_B^o = -14.5). The classification as an irregular dwarf results from the few HII regions of UGC 685. On an Hα{\alpha} Calar Alto 2.2m telescope CCD image, I identified only 5 HII regions. The total Hα{\alpha} flux corresponds to a mildly on-going star formation with a rate of 0.003 \Msolar yr−1^{-1}, a low rate even in comparison to other dwarfs. The available data do not indicate any major deviation from this rather low star formation rate within the last 10910^9 yr.Comment: 10 pages, 6 postscript figures. Astronomy and Astrophysics Supplement accepted Aug. 28, 199

    Husserl, Dummett, and the linguistic turn

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    Michael Dummett famously holds that the “philosophy of thought” must proceed via the philosophy of language, since that is the only way to preserve the objectivity of thoughts while avoiding commitments to “mythological,” Platonic entities. Central to Dummett’s case is his thesis that all thought contents are linguistically expressible. In this paper, I will (a) argue that making the linguistic turn is neither necessary nor sufficient to avoid the problems of psychologism, (b) discuss Wayne Martin’s argument that not all thought-contents are linguistically communicable, and (c) present another, stronger argument, derived from Husserl’s early account of fulfillment, that establishes the same conclusion

    Mechanical device accurately measures rf phase differences in vhf or uhf ranges

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    Dual range linear measurement device accurately measures RF phase differences in either VHF or UHF ranges. The device has a capability consisting of a course range extending to 30 cm readable to 1 mm and any fine range portion of 2.5 cm readable to .01 mm

    J.-B. Say's 1803 Treatise and the Coordination of Economic Activity

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    Although historians of economic thought emphasize J.-B. Say's contributions to utility theory, the structure of the subject matter of economics, entrepreneur theory and the construction of the "law of markets," they rarely appreciate what Say accomplished in the first edition of the TraitĂ© d'Économie Politique. Only in chapters 21 and 22 of his 1803 Treatise, however, does Say sketch business firms as institutions that create and operate markets. In doing so, he essentially provides the basis for a non-walrasian concept of the coordination problem of a decentralized economic system. Thus, concerning Adam Smith's metaphor of the "invisible hand," Say ought to be considered as the first theorist to introduce into economic literature what Robert W. Clower called the "visible fingers" of the "invisible hand." --Invisible Hand,General Equilibrium Theory,Jean-Baptiste Say,Market Maker,Say's Law,Des DĂ©bouchĂ©s

    A spectrophotometric catalogue of HII galaxies

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    We present a spectrophotometric catalogue of 90 emission-line galaxies (ELGs) discovered during an objective - prism survey that aimed to search for dwarf galaxies within the voids (Popescu et al. 1996, 1998). The paper presents line ratios, equivalent widths and absolute fluxes for the emission-lines seen in the spectra of the galaxies. A list of newly discovered Wolf-Rayet galaxies is presented. Many objects included in the catalogue have low metallicity and the extreme cases are proposed as candidates for very low metallicity galaxies.Comment: 14 pages, to appear in Astronomy and Astrophysics Suppl. Serie

    What drives Venture Capital Syndication

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    This paper analyses the syndication behavior of VC organisations and the factors influencing their overall propensity to co-invest. We develop hypothesis concerning the investment behavior of Venture Capitalists in the German market and compare these hypothesis to the actual empirical evidence from a data set including 2,500 VC investments. We find that the underlying theories of financial and resource driven motives can indeed be used to explain the observed behavior for syndicated venture capital investments. We show that mainly Resource driven motives foster the propensity to syndicate an investment. Additionally, we find that Venture Capital Firms tend to diversify their portfolio, such that both motives of venture capital syndication (Finance and Resource driven) seem to be present at the same time and play a significant role simultaneously for the decision to jointly co-invest. We find evidence that a lower level of experience and expertise fosters the need to syndicate an investment.Venture Capital, Syndication
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