462 research outputs found

    A CASE STUDY OF LUNTIAN MULTI-PURPOSE COOPERATIVE IN BARANGAY LALAIG, TIAONG, QUEZON, PHILIPPINES: A VERTICAL INTEGRATION APPROACH

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    The Luntian Multi-Purpose Cooperative located in Tiaong, Quezon, Philippines. The Luntian Multi-Purpose cooperative focuses more on feed production as well as hog fattening. The LMC applied the vertical integration to develop the cooperative. They have their members as their primary costumers of their feeds. The cooperative’s business activity includes also meat shop, granting of production loan, micro-finance, mobilization of saving deposits, aside from feed milling and hog fattening. Different agencies, industry organizations and private institutions provide trainings, seminars, assistance, as well as credit for the cooperative.The aims of the study was to determine the present and discuss a noteworthy business issue (s) of Luntian Multipurpose Cooperative, evaluate the business environment prevailing at a particular time of this case , assess the cooperative’s performance in terms of the four business functions , define the problem relevant to the business issue(s) being studied. The study used primary and secondary data. Primary data were gathered through interviews with the key personnel, managers, and other informants of the Luntian Multipurpose Cooperative in order to obtain responses regarding the overall status of the cooperative including its problem and plans. Secondary data were taken from files and documents, especially the history, background information and financial statements. Other data were taken through research materials such as book, unpublished special problems and from some government institutions. The recommendation of this research showed that Luntian MPC should engage in establishing a communal farm as to become the primary source of hybrid piglets that their members would raised. The alternatives solution was establishing a breeding farm that would ask for initial investment. Keywords: cooperative, vertical integration, case study, por

    Elemental Abundances in M31: Alpha and Iron Element Abundances from Low-Resolution Resolved Stellar Spectroscopy in the Stellar Halo

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    Measurements of [Fe/H] and [α\alpha/Fe] can probe the minor merging history of a galaxy, providing a direct way to test the hierarchical assembly paradigm. While measurements of [α\alpha/Fe] have been made in the stellar halo of the Milky Way, little is known about detailed chemical abundances in the stellar halo of M31. To make progress with existing telescopes, we apply spectral synthesis to low-resolution DEIMOS spectroscopy (R \sim 2500 at 7000 Angstroms) across a wide spectral range (4500 Angstroms << λ\lambda << 9100 Angstroms). By applying our technique to low-resolution spectra of 170 giant stars in 5 MW globular clusters, we demonstrate that our technique reproduces previous measurements from higher resolution spectroscopy. Based on the intrinsic dispersion in [Fe/H] and [α\alpha/Fe] of individual stars in our combined cluster sample, we estimate systematic uncertainties of \sim0.11 dex and \sim0.09 dex in [Fe/H] and [α\alpha/Fe], respectively. We apply our method to deep, low-resolution spectra of 11 red giant branch stars in the smooth halo of M31, resulting in higher signal-to-noise per spectral resolution element compared to DEIMOS medium-resolution spectroscopy, given the same exposure time and conditions. We find \langle[α\alpha/Fe]\rangle = 0.49 ±\pm 0.29 dex and \langle[Fe/H]\rangle = 1.59 ±\pm 0.56 dex for our sample. This implies that---much like the Milky Way---the smooth halo of M31 is likely composed of disrupted dwarf galaxies with truncated star formation histories that were accreted early in the halo's formation.Comment: 21 pages, 14 figures, accepted to Ap

    Towards a Comprehensive Fueling-Controlled Theory on the Growth of Massive Black Holes and Host Spheroids

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    We study the relation between nuclear massive black holes and their host spheroid gravitational potential. Using AMR numerical simulations, we analyze how gas is transported in the nuclear (central kpc) regions of galaxies. We study the gas fueling onto the inner accretion disk (sub-pc scale) and the star formation in a massive nuclear disk like those generally found in proto-spheroids (ULIRGs, SCUBA Galaxies). These sub-pc resolution simulation of gas fueling that is mainly depleted by star formation naturally satisfy the `M_BH - $M_virial' relation, with a scatter considerably less than the observed one. We found a generalized version of Kennicutt-Schmidt Law for starbursts is satisfied, in which the total gas depletion rate (dot{M}_gas = dot{M}_BH + dot{M}_SF) is the one that scales as M_gas/t_orbital. We also found that the `M_BH - sigma' relation is a byproduct of the `M_BH - M_virial' relation in the fueling controlled scenario.Comment: 12 pages, figures, submited to ApJ, email: [email protected]

    Elemental Abundances in M31: A Comparative Analysis of Alpha and Iron Element Abundances in the the Outer Disk, Giant Stellar Stream, and Inner Halo of M31

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    We measured [Fe/H] and [α/Fe] using spectral synthesis of low-resolution stellar spectroscopy for 70 individual red-giant-branch stars across four fields spanning the outer disk, Giant Stellar Stream (GSS), and inner halo of M31. Fields at M31-centric projected distances of 23 kpc in the halo, 12 kpc in the halo, 22 kpc in the GSS, and 26 kpc in the outer disk are α-enhanced, with ⟨ [α/Fe]〉= 0.43, 0.50, 0.41, and 0.58, respectively. The 23 and 12 kpc halo fields are relatively metal-poor, with ⟨ [Fe/H]⟩ = −1.54 and −1.30, whereas the 22 kpc GSS and 26 kpc outer disk fields are relatively metal-rich with ⟨ [Fe/H]⟩ = −0.84 and −0.92, respectively. For fields with substructure, we separated the stellar populations into kinematically hot stellar halo components and kinematically cold components. We did not find any evidence of a radial [α/Fe] gradient along the high surface brightness core of the GSS between ~17 and 22 kpc. However, we found tentative suggestions of a negative radial [α/Fe] gradient in the stellar halo, which may indicate that different progenitor(s) or formation mechanisms contributed to the build up of the inner versus outer halo. Additionally, the [α/Fe] distribution of the metal-rich ([Fe/H] > −1.5), smooth inner stellar halo (r_(proj) ≾ 26 kpc) is inconsistent with having formed from the disruption of a progenitor(s) similar to present-day M31 satellite galaxies. The 26 kpc outer disk is most likely associated with the extended disk of M31, where its high α-enhancement provides support for an episode of rapid star formation in M31's disk possibly induced by a major merger

    Contribución al conocimiento de los micromamíferos de Navarra (O. Insectivora y O. Rodentia)

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    Se han estudiado 8.700 cráneos de Micromamíferos procedentes de egagrópilas de Tyto alba y 135 ejemplares en piel de diversas localidades de Navarra. Se citan 24 especies pertenecientes a los órdenes Insectivora y Rodentia, de los que se da su distribución. Se puede observar una relación entre las condiciones climáticas, geográficas y de vegetación, y la presencia de determinadas especies en las distintas comarcas. Finalmente se muestra la abundancia en que cada especie está representada en las diversas zonas geográficas consideradas, mediante el análisis de egagrópilas de lechuza (Tyto alba)

    Morfometría de Sorex coronatus Millet, 1828 (Insectivora, Mammalia) en Navarra

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    Limiting eccentricity of sub-parsec massive black hole binaries surrounded by self-gravitating gas discs

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    We study the dynamics of supermassive black hole binaries embedded in circumbinary gaseous discs, with the SPH code Gadget-2. The sub-parsec binary (of total mass M and mass ratio q=1/3) has excavated a gap and transfers its angular momentum to the self--gravitating disc (M_disc=0.2 M). We explore the changes of the binary eccentricity e, by simulating a sequence of binary models that differ in the initial eccentricity e_0, only. In initially low-eccentric binaries, the eccentricity increases with time, while in high-eccentric binaries e declines, indicating the existence of a limiting eccentricity e_crit that is found to fall in the interval [0.6,0.8]. We also present an analytical interpretation for this saturation limit. An important consequence of the existence of e_crit is the detectability of a significant residual eccentricity e_LISA} by the proposed gravitational wave detector LISA. It is found that at the moment of entering the LISA frequency domain e_LISA ~ 10^{-3}-10^{-2}; a signature of its earlier coupling with the massive circumbinary disc. We also observe large periodic inflows across the gap, occurring on the binary and disc dynamical time scales rather than on the viscous time. These periodic changes in the accretion rate (with amplitudes up to ~100%, depending on the binary eccentricity) can be considered a fingerprint of eccentric sub-parsec binaries migrating inside a circumbinary disc.Comment: 10 pages, 7 figures, accepted for publication in MNRA

    Direct Formation of Supermassive Black Holes via Multi-Scale Gas Inflows in Galaxy Mergers

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    Observations of distant bright quasars suggest that billion solar mass supermassive black holes (SMBHs) were already in place less than a billion years after the Big Bang. Models in which light black hole seeds form by the collapse of primordial metal-free stars cannot explain their rapid appearance due to inefficient gas accretion. Alternatively, these black holes may form by direct collapse of gas at the center of protogalaxies. However, this requires metal-free gas that does not cool efficiently and thus is not turned into stars, in contrast with the rapid metal enrichment of protogalaxies. Here we use a numerical simulation to show that mergers between massive protogalaxies naturally produce the required central gas accumulation with no need to suppress star formation. Merger-driven gas inflows produce an unstable, massive nuclear gas disk. Within the disk a second gas inflow accumulates more than 100 million solar masses of gas in a sub-parsec scale cloud in one hundred thousand years. The cloud undergoes gravitational collapse, which eventually leads to the formation of a massive black hole. The black hole can grow to a billion solar masses in less than a billion years by accreting gas from the surrounding disk.Comment: 26 pages, 4 Figures, submitted to Nature (includes Supplementary Information
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