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We study the returns the venture capital and private equity investment from 221 venture capital and private equity funds that are part of 72 venture capital and private equity firms, 5040 entrepreneurial firms (3826 venture capital and 1214 private equity), and spanning 32 years (1971 - 2003) and 39 countries from North and South America, Europe and Asia. We make use of four main categories of variables to proxy for value-added activities and risks that explain venture capital and private equity returns: market and legal environment, VC characteristics, entrepreneurial firm characteristics, and the characteristics and structure of the investment. We show Heckman sample selection issues in regards to both unrealized and partially realized investments are important to consider for analysing the determinants of realized returns. We further compare the actual unrealized returns, as reported to investment managers, to the predicted unrealized returns based on the estimates of realized returns from the sample selection models. We show there exists significant systematic biases in the reporting of unrealized investments to institutional investors depending on the level of the earnings aggressiveness and disclosure indices in a country, as well as proxies for the degree of information asymmetry between investment managers and venture capital and private equity fund managers. Klassifikation: G24, G28, G31, G32, G35
The fires of January 2003 burnt much of the treeless high mountain country of Victoria, New South Wales and the Australian Capital Territory, and were the first extensive conflagration of this area since 1939. For this reason there are remarkably few studies of the response of alpine plants and vegetation to fire. A flora survey of treeless subalpine vegetation in the Kosciuszko area in late 2002 sampled 215 sites. Of the 119 sites that were burnt, 60 were relocated and re-sampled in late 2003 to assess the mode and extent of regeneration in a range of treeless plant communities. Twenty-four species (including 3 exotics) were recorded only in the pre-fire sampling. Fifty species (including 18 exotics) were recorded only in the post-fire sampling. One species, Chenopodium erosum, had not previously been recorded in Kosciuszko National Park, and is believed to be the first native chenopod recorded in alpine vegetation in Australia. There was no significant difference in mean number of species per quadrat between pre-fire and post-fire quadrats. The average number of weeds per quadrat was, however, significantly greater post-fire. Most of this difference was attributable to the significantly greater number of weeds per quadrat in bog vegetation after the fire. Of the 290 species recorded, 111 species regenerated from seed, 197 species regenerated from resprouting organs (roots, tubers and/or basal stems) and 49 species regenerated from both seed and resprouts. Based on the regeneration observed, most plant communities will return naturally to their pre-fire species composition and cover over a period between a few years and a few decades. Major exceptions will be those communities where the ‘keystone’ species appear to have been lost at least at a local scale. Principal amongst these are bog communities that incorporated significant biomass of Sphagnum cristatum pre-fire, Podocarpus lawrencei shrublands and Celmisia costiniana closed herbfields. Consideration might be given to augmenting their recovery. It will be important to exclude fire from these communities until their recovery is complete.
Respiratory chain complex I contains 8-9 iron-sulfur clusters. In several cases, the assignment of these clusters to subunits and binding motifs is still ambiguous. To test the proposed ligation of the tetranuclear iron-sulfur cluster N5 of respiratory chain complex I, we replaced the conserved histidine 129 in the 75-kDa subunit from Yarrowia lipolytica with alanine. In the mutant strain, reduced amounts of fully assembled but destabilized complex I could be detected. Deamino-NADH: ubiquinone oxidoreductase activity was abolished completely by the mutation. However, EPR spectroscopic analysis of mutant complex I exhibited an unchanged cluster N5 signal, excluding histidine 129 as a cluster N5 ligand.
This paper reports the results of a corpus investigation on case conflicts in German argument free relative constructions. We investigate how corpus frequencies reflect the relative markedness of free relative and correlative constructions, the relative markedness of different case conflict configurations, and the relative markedness of different conflict resolution strategies. Section 1 introduces the conception of markedness as used in Optimality Theory. Section 2 introduces the facts about German free relative clauses, and section 3 presents the results of the corpus study. By and large, markedness and frequency go hand in hand. However, configurations at the highest end of the markedness scale rarely show up in corpus data, and for the configuration at the lowest end we found an unexpected outcome: the more marked structure is preferred.
Weak function word shift
(2004)
The fact that object shift only affects weak pronouns in mainland Scandinavian is seen as an instance of a more general observation that can be made in all Germanic languages: weak function words tend to avoid the edges of larger prosodic domains. This generalisation has been formulated within Optimality Theory in terms of alignment constraints on prosodic structure by Selkirk (1996) in explaining thedistribution of prosodically strong and weak forms of English functionwords, especially modal verbs, prepositions and pronouns. But a purely phonological account fails to integrate the syntactic licensing conditions for object shift in an appropriate way. The standard semantico-syntactic accounts of object shift, onthe other hand, fail to explain why it is only weak pronouns that undergo object shift. This paper develops an Optimality theoretic model of the syntax-phonology interface which is based on the interaction of syntactic and prosodic factors. The account can successfully be applied to further related phenomena in English and German.
German dialects vary in which of the possible orders of the verbs in a 3-verb cluster they allow. In a still ongoing empirical investigation that I am undertaking together with Tanja Schmid, University of Stuttgart (Schmid and Vogel (2004)) we already found that each of the six logically possible permutations of the 3-verb cluster in (1) can be found in German dialects.
The aim of this paper is the exploration of an optimality theoretic architecture for syntax that is guided by the concept of "correspondence": syntax is understood as the mechanism of "translating" underlying representations into a surface form. In minimalism, this surface form is called "Phonological Form" (PF). Both semantic and abstract syntactic information are reflected by the surface form. The empirical domain where this architecture is tested are minimal link effects, especially in the case of "wh"-movement. The OT constraints require the surface form to reflect the underlying semantic and syntactic representations as maximally as possible. The means by which underlying relations and properties are encoded are precedence, adjacency, surface morphology and prosodic structure. Information that is not encoded in one of these ways remains unexpressed, and gets lost unless it is recoverable via the context. Different kinds of information are often expressed by the same means. The resulting conflicts are resolved by the relative ranking of the relevant correspondence constraints.
The argument that I tried to elaborate on in this paper is that the conceptual problem behind the traditional competence/performance distinction does not go away, even if we abandon its original Chomskyan formulation. It returns as the question about the relation between the model of the grammar and the results of empirical investigations – the question of empirical verification The theoretical concept of markedness is argued to be an ideal correlate of gradience. Optimality Theory, being based on markedness, is a promising framework for the task of bridging the gap between model and empirical world. However, this task not only requires a model of grammar, but also a theory of the methods that are chosen in empirical investigations and how their results are interpreted, and a theory of how to derive predictions for these particular empirical investigations from the model. Stochastic Optimality Theory is one possible formulation of a proposal that derives empirical predictions from an OT model. However, I hope to have shown that it is not enough to take frequency distributions and relative acceptabilities at face value, and simply construe some Stochastic OT model that fits the facts. These facts first of all need to be interpreted, and those factors that the grammar has to account for must be sorted out from those about which grammar should have nothing to say. This task, to my mind, is more complicated than the picture that a simplistic application of (not only) Stochastic OT might draw.
Hybrid robust deep and shallow semantic processing for creativity support in document production
(2004)
The research performed in the DeepThought project (http://www.project-deepthought.net) aims at demonstrating the potential of deep linguistic processing if added to existing shallow methods that ensure robustness. Classical information retrieval is extended by high precision concept indexing and relation detection. We use this approach to demonstrate the feasibility of three ambitious applications, one of which is a tool for creativity support in document production and collective brainstorming. This application is described in detail in this paper. Common to all three applications, and the basis for their development is a platform for integrated linguistic processing. This platform is based on a generic software architecture that combines multiple NLP components and on robust minimal recursive semantics (RMRS) as a uniform representation language.
Transforming constituent-based annotation into dependency-based annotation has been shown to work for different treebanks and annotation schemes (e.g. Lin (1995) has transformed the Penn treebank, and Kübler and Telljohann (2002) the Tübinger Baumbank des Deutschen (TüBa-D/Z)). These ventures are usually triggered by the conflict between theory-neutral annotation, that targets most needs of a wider audience, and theory-specific annotation, that provides more fine-grained information for a smaller audience. As a compromise, it has been pointed out that treebanks can be designed to support more than one theory from the start (Nivre, 2003). We argue that information can also be added to an existing annotation scheme so that it supports additional theory-specific annotations. We also argue that such a transformation is useful for improving and extending the original annotation scheme with respect to both ambiguous annotation and annotation errors. We show this by analysing problems that arise when generating dependency information from the constituent-based TüBa-D/Z.
The continuously growing natural killer (NK) cell line NK-92 is highly cytotoxic against malignant cells of various origin without affecting normal human cells. Based on this selectivity, the potential of NK-92 cells for adoptive therapy is currently being investigated in phase I clinical studies. To further enhance the antitumoral activity of NK-92 cells and expand the range of tumor entities suitable for NK-92-based therapies, here by transduction with retroviral vectors we have generated genetically modified NK-92 cells expressing chimeric antigen receptors specific either for the tumor-associated ErbB2 (HER2/neu) antigen or the human Epithelial Cell Adhesion Molecule (Ep-CAM). Both antigens are overexpressed by many tumors of epithelial origin. The chimeric antigen receptors consist of either the ErbB2 specific scFv(FRP5) antibody fragment or the Ep-CAM specific scFv(MOC31), a flexible hinge region derived from CD8, and transmembrane and intracellular regions of the CD3 zeta chain. Transduced NK-92-scFv(FRP5)-zeta or NK-92-scFv(MOC31)-zeta cells express high levels of the fusion proteins on the cell surface as determined by FACS analysis. In europium release assays no difference in cytotoxic activity of NK-92 and transduced NK-92 cells towards ErbB2 or Ep-CAM negative targets was found. However, even at low effector to target ratios transduced NK-92 cells specifically and efficiently lysed established ErbB2 or Ep-CAM expressing tumor cells that were completely resistant to cytolytic activity of parental NK-92 cells. Similarly, ErbB2-positive primary breast cancer cells isolated from pleural effusions of patients with recurrent disease were selectively killed by NK-92-scFv(FRP5)-zeta. In an in vivo model in immunodeficient mice treatment with retargeted NK-92-scFv(FRP5)-zeta, but not parental NK-92 cells resulted in markedly delayed growth of ErbB2 transformed cancer cells. These results demonstrate that efficient retargeting of NK-92 cytotoxicity can be achieved, and might allow the generation of potent cell-based therapeutics for the treatment of ErbB2 and Ep-CAM expressing malignancies. This therapeutic approach might be applicable for a large variety of different cancers where suitable cell surface antigens have been identified.
Religious Anthropology studies the origins, evolution and functions of religions. The discipline researching religious beliefs and rituals comparatively with cross-cultural perspectives tries to enlighten the belief world of the mankind. Religion, as a term, can be defined as "believing as well as worshipping to the supernatural powers and/or beings by the individual who are emotionally or consciously devoted to them" (Örnek 1988: 127). There have been a number of theories so far which try to bring an explanation to the origins and the evolution of religion. In these theories, Fetishism, cults of nature, animism, Totemism, dynamism, Manism, magic, polytheism, monotheism as well as certain physiological phenomena have been particularized as evolutionary stages and forms of belief (Evans-Pritchard 1998: 124). All of these theories have the perspective of so called "progressive" and / or "unilinear" that maintain a religion which has reached ongoing stages and that communities which have developed from primitiveness to civilization. They argue that there has only been one single line of progress, and all of the communities are bound to go through the same evolutionary stages.
Much has been written on the success of the Indian software industry, enumerating systemic factors like first-class higher education and research institutions, both public and private; low labour costs, stimulating (state) policies etc. However, although most studies analyzing the 'Indian' software industry cover essentially the South (and West) Indian clusters, this issue has not been tackled explicitly. This paper supplements the economic geography explanations mentioned above with the additional factor social capital, which is not only important within the region, but also in transnational (ethnic) networks linking Indian software clusters with the Silicon Valley. In other words, spatial proximity is complemented with cultural proximity, thereby, extending the system of innovation. The main hypothesis is that some Indian regions are more apt to economic development and innovation due to their higher affinity to education and learning, as well as, their more general openness, which has been a main finding of my interviews. In addition, the transnational networks of Silicon Valley Indians seem to be dominated by South Indians, thus, corroborating the regional clustering of the Indian software industry. JEL Classifications: O30, R12, Z13, L86
This paper aims to analyze the impact of different types of venture capitalists on the performance of their portfolio firms around and after the IPO. We thereby investigate the hypothesis that different governance structures, objectives and track record of different types of VCs have a significant impact on their respective IPOs. We explore this hypothesis by using a data set embracing all IPOs which occurred on Germany's Neuer Markt. Our main finding is that significant differences among the different VCs exist. Firms backed by independent VCs perform significantly better two years after the IPO compared to all other IPOs and their share prices fluctuate less than those of their counterparts in this period of time. Obviously, independent VCs, which concentrated mainly on growth stocks (low book-to-market ratio) and large firms (high market value), were able to add value by leading to less post-IPO idiosyncratic risk and more return (after controlling for all other effects). On the contrary, firms backed by public VCs (being small and having a high book-to-market ratio) showed relative underperformance. Klassifikation: G10, G14, G24 . 29th January 2004 .
This paper sets out to analyze the influence of different types of venture capitalists on the performance of their portfolio firms around and after IPO. We investigate the hypothesis that different governance structures, objectives, and track records of different types of VCs have a significant impact on their respective IPOs. We explore this hypothesis using a data set embracing all IPOs that have occurred on Germany's Neuer Markt. Our main finding is that significant differences among the different VCs exist. Firms backed by independent VCs perform significantly better two years after IPO as compared to all other IPOs, and their share prices fluctuate less than those of their counterparts in this period of time. On the contrary, firms backed by public VCs show relative underperformance. The fact that this could occur implies that market participants did not correctly assess the role played by different types of VCs.
As the exilic experience, initiated in 587 B.C.E., continued over millennia, no one has been able to settle the question of what it means to be a diaspora Jew. Are those who actively participate in non-Jewish life still in a position to claim the heritage of Israel? And what about Jews who actively seek assimilation and renounce their roots altogether: are they still Jews in spite of themselves? Authors, from Joseph Roth to Sholom Aleichem to Chaim Potok, have tried to deal with this issue in light of different diaspora circumstances. One of the most recent perspectives on Jewish identity comes to us through "Sunshine", a powerful film by the Hungarian director Istvan Szabó (1999). Szabó, who wrote the screenplay with Israel Horowitz, tells the story of several generations in one Hungarian Jewish family: the Sonnenscheins. Living at the turn of the twentieth century, the patriarch of the Sonnenschein clan is Emmanuel, a successful distiller who seems to have found a balance between the two exilic extremes: neither complete assimilation, nor a retreat from gentile society.
Im Rahmen dieser Dissertation wurde die Photophysik und die elektronische Struktur einer Klasse neuartiger Donator-Akzeptor-Ladungstransfer-Komplexe untersucht. Im Wesentlichen bestehen diese Verbindungen aus einem Ferrocen-Donator (Fc) und organischen Akzeptoren, die über B-N-Bindungen verbrückt sind, welche sich bei dieser Art von makromolekularen Systemen spontan bilden. Zentraler Gegenstand dieser Arbeit war die spektroskopische Untersuchung des Metall-zu-Ligand-Ladungstransfers (engl. Abkürzung: MLCT) im elektronischen Anregungszustand dieser kationischen Komplexverbindungen, die im Weiteren als „Fc-B-bpy“-Verbindungen bezeichnet werden. Die vorliegende Arbeit analysiert eine Vielzahl miteinander verwandter Fc-B-bpy-Derivate. Die Arbeit ist gegliedert in 1.) die Analyse der Absorptionsspektren vom UV- bis zum nahen Infrarot-Spektralbereich (250-1000 nm) von Lösungen, dotierten Polymer-Dünnfilmen und Einkristallen, 2.) die zeitaufgelöste optische Spektroskopie des angeregten Zustands auf der Pikosekunden-Zeitskala, 3.) die Analyse elektrochemischer Messungen an Lösungen, und 4.) die Auswertung quantenchemischer Berechnungen. Für die zeitaufgelösten Messungen wurde ein komplexes optisches Spektroskopie-System mit breitbandigen Femtosekunden-Pulsen sowie den entsprechenden zeitaufgelösten Detektionsmethoden (spektral gefilterte Weißlicht-Detektion) aufgebaut. Die Ergebnisse dieser Arbeit beweisen die Existenz eines MLCT-Übergangs mit fast vollständigem Übergang eines Fc-Donator-Elektrons zum B-bpy-Akzeptor bei optischer Anregung. Die vergleichenden Untersuchungen der spektroskopischen Eigenschaften verschiedener Derivate liefern wichtige Information für die Entwicklung neuartiger Derivate, einschließlich verwandter Polymere, mit verbesserten spektroskopischen Eigenschaften. Es wurden transiente Absorptionsmessungen bestimmter Fc-B-bpy-Derivate in Lösung nach gepulster Anregung der MLCT-Bande (bei 500 nm) über einen Zeitbereich von 0,1-1000 ps und einen Wellenlängenbereich von 460-760 nm vorgenommen. Aus den Messergebnissen geht hervor, dass die Relaxation aus dem angeregten MLCT-Zustand in den Grundzustand auf verschiedenen Zeitskalen geschehen kann, welche im Bereich zwischen ~18 und 900 ps liegen. Ein Vergleich verschiedener Derivate mit unterschiedlicher Flexibilität in der Konformation zeigt, dass die Starrheit der Bindungen zwischen Donatoren und Akzeptoren ein wesentlicher Faktor für die Lebensdauer des angeregten Zustands ist. Wenn die Akzeptorgruppen relativ frei rotieren können, ist es der Verbindung möglich, eine Geometrie einzunehmen, von der aus ein effizienter, strahlungsfreier Übergang in den Grundzustand erfolgen kann. Dieser Befund zeigt einen Weg auf, wie neuartige, verwandte Verbindungen mit größerer Lebensdauer das angeregten Zustands synthetisiert werden können, indem darauf geachtet wird, daß eine starre molekulare Architektur zwischen Donator und Akzeptor verwirklicht wird.
In the wake of Kayne's Antisymmetry Hypothesis and Linear Correspondence Axiom (LCA), there has been much fruitful research attempting to adjust syntactic analyses to those permitted by Kayne's restrictive system. In doing so, analyses which at first seem counter-intuitive may tum out to provide solutions to old problems. Two cases in point are the analysis of Malagasy involving extensive Remnant Movement [henceforth RM1 described in Rackowski & Travis (2000), Pearson (2001), and elsewhere; on the one hand, and the analysis of Hungarian and Dutch verbal clusters in Koopman & Szabolcsi (2000) [henceforth R&T, Pearson, and K&Sz].
The original motivation (in part) for examining L&Sz and subsequently R&T was that it is the extensive use of iterated RM which increases the computational complexity of languages generatable in Stabler's "Strict Minimalist Grammar" formalism over that of context-free grammars. It has also been noted that allowing extraction from complex specifiers created by Merge (as opposed to Move) increases the level of complexity even further (lens Michaelis, p.e.). Both R&T and K&Sz make extensive use of RM; R&T allow extraction from complex specifiers, while K&Sz do not. Although the specifiers in both cases are created by Move, not Merge, we nevertheless feel that there is enough intrinsic linguistic interest in trying to limit extraction possibilities to pursue the comparison of these two systems with regard to this point.