Towards ontological foundations for agent modeling concepts using UFO

Foundational ontologies provide the basic concepts upon which any domain-specific ontology is built. This paper presents a new foundational ontology, UFO, and shows how it can be used as a foundation of agent concepts and for evaluating agent-oriented modeling methods. UFO is derived from a synthesis of two other foundational ontologies, GFO/GOL and OntoClean/DOLCE. While their main areas of application are the natural sciences and linguistics/cognitive engineering, respectively, the main purpose of UFO is to provide a foundation for conceptual modeling, including agentoriented modeling

Kontrolle der Expression des UNUSUAL FLORAL ORGANS (UFO) Gens in Arabidopsis thaliana

Die vorliegende Arbeit befaßt sich mit der Kontrolle des Expressionsmusters des UNUSUAL FLORAL ORGANS (UFO) Gens von Arabidopsis thaliana. UFO wird im Sproß- und Blütenmeristemen aller Entwicklungsstadien der Pflanze exprimiert. In Blütenmeristemen agiert UFO als Kofaktor von LEAFY (LFY) bei der Aktivierung der Organidentitätsgene des zweiten und dritten Wirtels. UFO stellt also einen generellen Faktor der Musterbildung in Meristemen dar. Um regulatorische Gene, die die Expression von UFO beeinflussen, zu identifizieren, wurden transgene Pflanzen, die GFP unter Kontrolle des UFO-Promotors exprimieren (UFO::GFP) mutagenisiert. Anhand der GFP-Expression wurde nach Mutanten gesucht, in denen UFO im Keimlingsstadium fehlexprimiert wird. Zusätzlich wurde durch eine Deletionsanalyse des UFO-Promotors die Kontrolle der UFO-Expression durch cis-regulatorische Sequenzen untersucht. Bei der Analyse der mutagenisierten UFO::GFP-Pflanzen konnte eine Mutante identifiziert werden, in der UFO nicht exprimiert wird. Das betroffene Gen konnte isoliert und als neues Allel von WUSCHEL (WUS) identifiziert werden. WUS kodiert einen Homöodomänen-Transkriptionsfaktor, der in der zentralen Zone von Sproß- und Blütenmeristemen exprimiert wird und ein positiver Regulator des Stammzellschicksals ist. Durch WUS-Fehlexpressionsexperimente konnten gezeigt werden, daß WUS in Sproß- und Blütenmeristemen UFO-Expression aktiviert. WUS aktiviert UFO-Expression aber nicht direkt, sondern benötigt dafür meristematische Kofaktoren. Ektopische WUS-Expression in der Wurzel führte bei hohen Auxinkonzentrationen zur Umprogrammierung von Zellen auf ein sproßmeristematisches Schicksal. Das hatte zur Folge, daß auch die für die Expression von UFO benötigten Kofaktoren exprimiert werden und WUS somit UFO-Expression aktivieren kann. Anschließende Fehlexpressionsexperimente mit dem SHOOT MERISTEMLESS (STM) Gen zeigten, daß auch STM ein indirekter Aktivator der UFO-Expression ist. Die Deletionsanalyse zeigte, daß der UFO-Promotor sich aus mehreren, in verschiedenen Promotorregionen gelegenen cis-Elemente zusammensetzt. UFO-Expression in Blütenmeristemen und im Sproßmeristemen werden also durch separate regulatorische Sequenzen kontrolliert. Auch die Kontrolle der UFO-Expression im Sproßmeristem wird durch getrennte cis-Elemente gewährleistet, da sich das UFO-Expressionsmuster durch 5´- Deletionen des Promotors in eine zentrale und eine periphere Teildomäne trennen läßt. Die zentrale Teildomäne ist mit dem WUS-Expressionsmuster identisch; möglicherweise vermittelt WUS also die positionale Information für diesen Teil des UFO-Expressionsmusters

The multi-phase winds of Markarian 231: from the hot, nuclear, ultra-fast wind to the galaxy-scale, molecular outflow

We present the best sensitivity and angular resolution maps of the molecular disk and outflow of Mrk 231, as traced by CO observations obtained with IRAM/PdBI, and we analyze archival Chandra and NuSTAR observations. We constrain the physical properties of both the molecular disk and outflow, the presence of a highly-ionized ultra-fast nuclear wind, and their connection. The molecular outflow has a size of ~1 kpc, and extends in all directions around the nucleus, being more prominent along the south-west to north-east direction, suggesting a wide-angle biconical geometry. The maximum projected velocity of the outflow is nearly constant out to ~1 kpc, thus implying that the density of the outflowing material decreases from the nucleus outwards as $r^{-2}$. This suggests that either a large part of the gas leaves the flow during its expansion or that the bulk of the outflow has not yet reached out to ~1 kpc, thus implying a limit on its age of ~1 Myr. We find $\dot M_{OF}=[ 500-1000]~ M_{\odot}~yr^{-1}$ and $\dot E_{kin,OF}=[7-10]\times 10^{43}$ erg s$^{-1}$. Remarkably, our analysis of the X-ray data reveals a nuclear ultra-fast outflow (UFO) with velocity -20000 km s$^{-1}$, $\dot M_{UFO}=[0.3- 2.1] ~M_\odot yr^{-1}$, and momentum load $\dot P_{UFO}/\dot P_{rad}=[0.2-1.6]$.We find $\dot E_{kin,UFO}\sim \dot E_{kin,OF}$ as predicted for outflows undergoing an energy conserving expansion. This suggests that most of the UFO kinetic energy is transferred to mechanical energy of the kpc-scale outflow, strongly supporting that the energy released during accretion of matter onto super-massive black holes is the ultimate driver of giant massive outflows. We estimate a momentum boost $\dot P_{OF}/\dot P_{UFO}\approx [30-60]$. The ratios $\dot E_{kin, UFO}/L_{bol,AGN} =[ 1-5]\%$ and $\dot E_{kin,OF}/L_{bol,AGN} = [1-3]\%$ agree with the requirements of the most popular models of AGN feedback.Comment: 16 pages, 17 figures. Accepted for publication in A&

Endurant Types in Ontology-Driven Conceptual Modeling: Towards OntoUML 2.0

For over a decade now, a community of researchers has contributed to the development of the Unified Foundational Ontology (UFO) - aimed at providing foundations for all major conceptual modeling constructs. This ontology has led to the development of an Ontology-Driven Conceptual Modeling language dubbed OntoUML, reflecting the ontological micro-theories comprising UFO. Over the years, UFO and OntoUML have been successfully employed in a number of academic, industrial and governmental settings to create conceptual models in a variety of different domains. These experiences have pointed out to opportunities of improvement not only to the language itself but also to its underlying theory. In this paper, we take the first step in that direction by revising the theory of types in UFO in response to empirical evidence. The new version of this theory shows that many of the meta-types present in OntoUML (differentiating Kinds, Roles, Phases, Mixins, etc.) should be considered not as restricted to Substantial types but instead should be applied to model Endurant Types in general, including Relator types, Quality types and Mode types. We also contribute a formal characterization of this fragment of the theory, which is then used to advance a metamodel for OntoUML 2.0. Finally, we propose a computational support tool implementing this updated metamodel

Impact of Financial Distress on the Liquidity of Selected Manufacturing Firms of Ethiopia

It is not uncommon to see manufacturing firms struggling to turnaround from their financial distress.  Liquidity ratio has important implication on the firm’s solvency. With this in mind, the main objective of the study is to examine the relationship between liquidity and financial distress of manufacturing firms in Ethiopia for the period from 1999 to 2005. Besides this the research examines various other factors affecting financial distress. Due to data heterogeneity, non-continuity and because the Hausman test favors it over the Random Effect technique, the panel data General Least Square  (GLS) regression method is used. The result proves that liquidity, profitability, and efficiency have positive and significant influence on debt service coverage.  On contrary, leverage has negative and significant influence on Debt Service coverageTo save infant manufacturing firms, policy makers have the opportunity to influence the financing policy of the firms in the promotion of equity financing by controlling leverage. Banks should supervise the liquidity, solvency, profitability and efficiency of firms in mitigating the debt burden through application of various techniques during loan evaluation process. The appropriate firm executives should consider improving efficiency of firm’s performance through retrenchment of assets and replacing, liquidity through improving cash collection, profitability through replacement of departments, products or lines of the business. FD have a negative impact on DSC and leading firms to bankruptcy and liquidation and can cause economic, social and political impact on manufacturing firms and contribute to the CEO resignation, employee’s layoff or loss of jobs, dividend reduction, plant closing and related consequential health and moral distress. Keywords: Financial Distress, liqudity, Ethiopi

Impact of Financial Distress on the Profitability of Selected Manufacturing Firms of Ethiopia

In recent decades manufacturing sectors are suffering from financial distress.  Profitability is presumed to play a role in addressing this problem. With this in mind, the main objective of the study is to determine the relationship between financial distress and profitability of manufacturing firms in Ethiopia for the period from 1999 to 2005. Due to non-homogeneity data, non-continuity and because the Hausman test favors it over the Random Effect technique, the panel data General Least Square  (GLS) regression method is used. The result proves that profitability has positive and significant influence on debt service coverage as proxy for financial distress.  Banks should supervise the profitability of firms at time of loan approval to avoid default risk caused by operational insolvency. The appropriate firm executives should consider improving profitability of firm through replacement of departments, products or lines of the business. FD have a negative impact on profitability and leading firms to insolvency and shortage of cash flow for current payment of debts and results in several consequential effects. Keywords: Financial Distress, Profitability, Ethiopi

Impact of Financial Distress on the Leverage of Selected Manufacturing Firms of Ethiopia

Leverage ratio is known to play a significant implication in financial condition firms. The main objective of the study is to examine the relationship between leverage and manufacturing firms’ financial distress in Ethiopia from nineteen-ninety nine to two thousand five. Random Effect technique, the panel data General Least Square regression method is used. The result shows that leverage has negative and significant influence on financial distress.Manufacturing firms should consider the optimal debt capacity of them. Minimize the bank loans through equity financing. Improve cash collection and reduce bad debt expenses as remedy for maintaining short term cash problem. Keywords: Financial Distress, Leverage, Debt service Coverage, Ethiopi