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Intra-arterial (IA) chemotherapy for curative treatment of head and neck cancer experienced a revival in the last decade. Mainly, it was used in concurrent combination with radiation in organ-preserving settings. The modern method of transfemoral approach for catheterisation, superselective perfusion of the tumour-feeding vessel, and high-dose (150 mg m−2) administration of cisplatin with parallel systemic neutralisation with sodium thiosulphate (9 g m−2) made preoperative usage feasible. The present paper presents the results of a pilot study on a population of 52 patients with resectable stage 1–4 carcinomas of the oral cavity and the oropharynx, who were treated with one cycle of preoperative IA chemotherapy executed as mentioned above and radical surgery. There have been no interventional complications of IA chemotherapy, and acute side effects have been low. One tracheotomy had to be carried out due to swelling. The overall clinical local response has been 69%. There was no interference with surgery, which was carried out 3–4 weeks later. Pathological complete remission was assessed in 25%. The mean observation time was 3 years. A 3-year overall and disease-free survival was 82 and 69%, respectively, and at 5 years 77 and 59%, respectively. Survival results were compared to a treatment-dependent prognosis index for the same population. As a conclusion, it can be stated that IA high-dose chemotherapy with cisplatin and systemic neutralisation in a neoadjuvant setting should be considered a feasible, safe, and effective treatment modality for resectable oral and oropharyngeal cancer. The low toxicity of this local chemotherapy recommends usage especially in stage 1–2 patients. The potential of survival benefit as indicated by the comparison to the prognosis index should be controlled in a randomised study.
National borders in Europe have been opening since 1992 and the Union is expanding to embrace more countries prompting enterprises to consider alternative and more attractive locations outside their home country to handle part of their activities (Van Dijk and Pellenbarg, 2000; Cantwell and Iammarino, 2002). International relocation is becoming more and more popular even for small and medium-sized firms that are involved in a growing internationalisation process, mirroring the path of multinational enterprises. Italy, like other industrialised countries, is experiencing a fragmentation of the production chain: firms tend to shift high labour-intensive manufacturing activities to areas characterised by an abundance of low-cost labour (i.e. Central Eastern Europe, India, South East Asia, Latin America, Russia and Central Asia). The internationalisation process by Italian district SMEs has assumed significant dimensions. It has become a relevant topic in recent economic debate because of its consequences for the local context and, in particular, the implication for the survival of the Italian district model (see, among others, Becattini, 2002; Rullani, 1998 and Cor, 2000). The purpose of the paper is twofold: it aims at (i) identifying the managerial approaches to the internationalisation process adopted by the Italian district SMEs and by the Industrial District (ID) itself and (ii) at investigating whether the international delocalisation to the South Eastern European countries (SEECs) constitutes a threat or an opportunity for the Italian district model. The paper is organised as follows. The general introduction is followed by a description of the evolution of the internationalisation processes in Italy over the last three decades. Section three presents a discussion of the internationalisation strategies adopted by Italian SMEs. Section four focuses on the internationalisation process of the Italian industrial districts SMEs. A review of the studies on the subject is offered in section five. Section six presents a qualitative study on the internationalisation process as undergone by sports shoes manufacturers in the Montebelluna district, in north-east Italy. This study shows different managerial strategies to the internationalisation process and emphasises that the motivations can evolve over time, from originally cost-saving to increasingly market-oriented or global strategies. On the basis of a literature review, section seven investigates whether internationalisation constitutes a threat (i.e. loss of jobs and knowledge) or an opportunity (i.e. enlargement of the ID, update district s competitiveness) for the district model. Finally, some summarising remarks in section eight conclude the paper.
As of today, estimating interest rate reaction functions for the Euro Area is hampered by the short time span since the conduct of a single monetary policy. In this paper we circumvent the common use of aggregated data before 1999 by estimating interest rate reaction functions based on a panel including actual EMU Member States. We find that exploiting the cross-section dimen- sion of a multi-country panel and accounting for cross-country heterogeneity in advance of the single monetary policy pays off with regard to the estimated reaction functions' ability to describe actual interest rate dynamics. We retrieve a panel reaction function which is demonstrated to be a valuable tool for evaluating episodes of monetary policy since 1999. JEL - Klassifikation: E43 , E58 , C33
This paper considers a theoretical model of n asymmetric firms that reduce their initial unit costs by spending on R&D activities. In accordance with Schumpeterian hypotheses we obtain that more efficient (bigger) firms spend more in R&D and this leads to a more concentrated market structure. We also find a positive relationship between innovation and market concentration. This calls for a corrective tax on R&D activities to curtail strategic incentives to over-invest in R&D trying to achieve a higher market share. Klassifikation: L11, L52, O31 . February, 2004.
We investigate the connection between corporate governance system configurations and the role of intermediaries in the respective systems from a informational perspective. Building on the economics of information we show that it is meaningful to distinguish between internalisation and externalisation as two fundamentally different ways of dealing with information in corporate governance systems. This lays the groundwork for a description of two types of corporate governance systems, i.e. insider control system and outsider control system, in which we focus on the distinctive role of intermediaries in the production and use of information. It will be argued that internalisation is the prevailing mode of information processing in insider control system while externalisation dominates in outsider control system. We also discuss shortly the interrelations between the prevailing corporate governance system and types of activities or industry structures supported.
Teaching information literacy: substance and process This presentation explores the concept of information literacy within the broader context of higher education. It argues that, certain assertions in the library literature notwithstanding, the concepts associated with information literacy are not new, but rather very closely resemble the qualities traditionally considered to characterize a well-educated person. The presentation also considers the extent to which the higher education system does indeed foster the attributes commonly associated with information literacy. The term information literacy has achieved the immediacy it currently enjoys within the library community with the advent of the so-called "information age" The information age is commonly touted in the literature, both popular and professional, as constituting nothing short of a revolution. Academic librarians and other educators have of course felt called upon to make their teaching reflect both the growing proliferation of information formats and the major transformations affecting the process of information seeking. Faced with so much novelty and uncertainty, it is no surprise that many have felt that these changes call for a revolution in teaching. It is within this context that the concept of information literacy has flourished. It is argued in this presentation, however, that by treating information literacy as an essentially new specialty that owes much of its importance to the plethora of electronic information, we risk obscuring some of the most fundamental and enduring educational values we should be imparting to our students. Much of the literature on information literacy assumes - rather than argues - that recent changes in the way we approach education are indications of progress. Indeed, much of the self-narrative that institutions produce (in bulletins, mission statements, web sites, etc.) endorses an approach to education that will result in lifelong learners who are critical consumers of information. After critically examining the degree to which such statements of educational approach reflect reality, this presentation concludes by considering the effects of certain changes in the culture of higher education. It considers particularly the transformation - at least in North America - of the traditional model of higher education as a public good to a market-driven business model. It poses the question of whether a change of this significance might in fact detract from, rather than promote, the development of information literate students.
Chemically modified bases are frequently used to stabilize nucleic acids, to study the driving forces for nucleic acid structure formation and to tune DNA and RNA hybridization conditions. In particular, fluorobenzene and fluorobenzimidazole base analogues can act as universal bases able to pair with any natural base and to stabilize RNA duplex formation. Although these base analogues are compatible with an A-form RNA geometry, little is known about the influence on the fine structure and conformational dynamics of RNA. In the present study, nano-second molecular dynamics (MD) simulations have been performed to characterize the dynamics of RNA duplexes containing a central 1'-deoxy-1'-(2,4-difluorophenyl)-ß-D-ribofuranose base pair or opposite to an adenine base. For comparison, RNA with a central uridine:adenine pair and a 1'-deoxy-1'-(phenyl)-ß-D-ribofuranose opposite to an adenine was also investigated. The MD simulations indicate a stable overall A-form geometry for the RNAs with base analogues. However, the presence of the base analogues caused a locally enhanced mobility of the central bases inducing mainly base pair shear and opening motions. No stable ‘base-paired’ geometry was found for the base analogue pair or the base analogue:adenine pairs, which explains in part the universal base character of these analogues. Instead, the conformational fluctuations of the base analogues lead to an enhanced accessibility of the bases in the major and minor grooves of the helix compared with a regular base pair.
Ida'an-Begak is a Western Malayo-Polynesian language spoken by approximately 6,000 people on the east coast of Sabah, Malaysia, Borneo and belongs to the Sabahan subgroup of the North Borneo subgroup (Blust 1998). Ida'an-Begak has three dialects, Ida'an, spoken in the villages of Segama to the west of Lahad Datu, Ida'an Sungai spoken in the Kinabatangan and Sandakan districts, and Begak spoken in Ulu Tungku, to the east of Lahad Datu (Banker 1984).1 Moody (1993) deals with Ida'an; this paper concentrates on the Begak dialect. In this paper I will present new data gathered in the field and provide an analysis of the allomorphy. The study is based on spontaneous data as well as examples elicited from my language informants.
The hadronic final state of central Pb+Pb collisions at 20, 30, 40, 80, and 158 AGeV has been measured by the CERN NA49 collaboration. The mean transverse mass of pions and kaons at midrapidity stays nearly constant in this energy range, whereas at lower energies, at the AGS, a steep increase with beam energy was measured. Compared to p+p collisions as well as to model calculations, anomalies in the energy dependence of pion and kaon production at lower SPS energies are observed. These findings can be explained, assuming that the energy density reached in central A+A collisions at lower SPS energies is sufficient to transform the hot and dense nuclear matter into a deconfined phase.
The hadronic final state of central Pb+Pb collisions at 20, 30, 40, 80, and 158 AGeV has been measured by the CERN NA49 collaboration. The mean transverse mass of pions and kaons at midrapidity stays nearly constant in this energy range, whereas at lower energies, at the AGS, a steep increase with beam energy was measured. Compared to p+p collisions as well as to model calculations, anomalies in the energy dependence of pion and kaon production at lower SPS energies are observed. These findings can be explained, assuming that the energy density reached in central A+A collisions at lower SPS energies is sufficient to force the hot and dense nuclear matter into a deconfined phase.
While the sortal constraints associated with Japanese numeral classifiers are wellstudied, less attention has been paid to the details of their syntax. We describe an analysis implemented within a broadcoverage HPSG that handles an intricate set of numeral classifier construction types and compositionally relates each to an appropriate semantic representation, using Minimal Recursion Semantics.
We study the phase diagram of a generalized chiral SU(3)-flavor model in mean-field approxi- mation. In particular, the influence of the baryon resonances, and their couplings to the scalar and vector fields, on the characteristics of the chiral phase transition as a function of temperature and baryon-chemical potential is investigated. Present and future finite-density lattice calculations might constrain the couplings of the fields to the baryons. The results are compared to recent lattice QCD calculations and it is shown that it is non-trivial to obtain, simultaneously, stable cold nuclear matter.
Transverse mass and rapidity distributions for charged pions, charged kaons, protons, and antiprotons are reported for sqrt[sNN]=200 GeV pp and Au+Au collisions at Relativistic Heary Ion Collider (RHIC). Chemical and kinetic equilibrium model fits to our data reveal strong radial flow and long duration from chemical to kinetic freeze-out in central Au+Au collisions. The chemical freeze-out temperature appears to be independent of initial conditions at RHIC energies.
Dendritic cells (DC) are known to present exogenous protein Ag effectively to T cells. In this study we sought to identify the proteases that DC employ during antigen processing. The murine epidermal-derived DC line Xs52, when pulsed with PPD, optimally activated the PPD-reactive Th1 clone LNC.2F1 as well as the Th2 clone LNC.4k1, and this activation was completely blocked by chloroquine pretreatment. These results validate the capacity of XS52 DC to digest PPD into immunogenic peptides inducing antigen specific T cell immune responses. XS52 DC, as well as splenic DC and DCs derived from bone marrow degraded standard substrates for cathepsins B, C, D/E, H, J, and L, tryptase, and chymases, indicating that DC express a variety of protease activities. Treatment of XS52 DC with pepstatin A, an inhibitor of aspartic acid proteases, completely abrogated their capacity to present native PPD, but not trypsin-digested PPD fragments to Th1 and Th2 cell clones. Pepstatin A also inhibited cathepsin D/E activity selectively among the XS52 DC-associated protease activities. On the other hand, inhibitors of serine proteases (dichloroisocoumarin, DCI) or of cystein proteases (E-64) did not impair XS52 DC presentation of PPD, nor did they inhibit cathepsin D/E activity. Finally, all tested DC populations (XS52 DC, splenic DC, and bone marrow-derived DC) constitutively expressed cathepsin D mRNA. These results suggest that DC primarily employ cathepsin D (and perhaps E) to digest PPD into antigenic peptides.
IAD annual report 2004
(2004)
New results on the production of Xi and Omega hyperons in Pb+Pb interactions at 40 A GeV and Lambda at 30 A GeV are presented. Transverse mass spectra as well as rapidity spectra of these hyperons are shown and compared to previously measured data at different beam energies. The energy dependence of hyperon production (4Pi yields) is discussed. Additionally, the centrality dependence of Xi- production at 40 A GeV is presented.
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.
Pathologic data indicate that human cytomegalovirus (HCMV) infection might be associated with the pathogenesis of several human malignancies. However, no definitive evidence of a causal link between HCMV infection and cancer dissemination has been established to date. This study describes the modulation of the invasive behavior of NCAM-expressing tumor cell lines by HCMV. Neuroblastoma (NB) cells, persistently infected with the HCMV strain AD169 (UKF-NB-4AD169 and MHH-NB-11AD169), were added to endothelial cell monolayers and adhesion and penetration kinetics were measured. The 140- and 180-kDa isoforms of the adhesion receptor NCAM were evaluated by flow cytometry, Western blot, and reverse transcriptionpolymerase chain reaction (RT-PCR). The relevance of NCAM for tumor cell binding was proven by treating NB with NCAM antisense oligonucleotides or NCAM transfection. HCMV infection profoundly increased the number of adherent and penetrated NB, compared to controls. Surface expression of NCAM was significantly lower on UKF-NB-4AD169 and MHH-NB-11AD169, compared to mock-infected cells. Western-blot and RT-PCR demonstrated reduced protein and RNA levels of the 140- and 180-kDa isoform. An inverse correlation between NCAM expression and adhesion capacity of NB has been shown by antisense and transfection experiments. We conclude that HCMV infection leads to downregulation of NCAM receptors, which is associated with enhanced tumor cell invasiveness.
How the left-periphery of a wh-relative clause determines its syntactic and semantic relationships
(2004)
This paper discusses a certain class of German relative clauses which are characterized by a wh-expression overtly realized at the left periphery of the clause. While investigating empirical and theoretical issues regarding this class of relatives, it argues that a wh-relative clause relates syntactically to a functionally complete sentential projection and semantically to entities of various kinds that are abstracted from the matrix clause. What is shown is that this grammatical behaviour clearly can be attributed to the properties of the elements positioned at the left of a wh-relative clause. Finally, a lexically-based analysis couched in the framework of HPSG is given that accounts for the data presented.
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.
Calcium-activated potassium channels are fundamental regulators of neuron excitability. SK channels are activated by an intracellular increase of Ca++ (such as occurs during an action potential). They have a small single channel conductance (less than 20pS) and show no voltage dependence of activation. To date, there are only a few examples of high-resolution structures of eukaryotic membrane proteins. All of them were purified from natural sources. Since no abundant natural sources of eukaryotic K+ channels are available we overexpressed rSK2 in order to produce the quantities necessary for structural analysis. Unfortunately the Pichia pastoris expression system did not yield sufficient amount of pure protein, mainly because most of the protein was retained by in the ER and was only partially soluble. Subsequently, two constructs were expressed: SK2-FCYENE (containing a specific sequence that promotes surface expression), and SK2-q-CaM a concatamer of SK2 and calmodulin. Although these proved an improvement in terms of solubilisation, little improvement was found in terms of amounts of purified material obtained. For this reason we tested the Semliki Forest virus expression system, since the protein is expressed in a mammalian system where we hoped that it would be trafficked in the same way as in vivo. Using this system it was possible to express rSK2 and solubilise it with several detergents and to achieve much better purification. However, the levels were still not sufficient for high-resolution structural studies, although sufficient for single particle electron microscopy analysis.
The objective of this paper is the study of the equilibrium behavior of a population on the hierarchical group ΩN consisting of families of individuals undergoing critical branching random walk and in addition these families also develop according to a critical branching process. Strong transience of the random walk guarantees existence of an equilibrium for this two-level branching system. In the limit N→∞ (called the hierarchical mean field limit), the equilibrium aggregated populations in a nested sequence of balls B(N)ℓ of hierarchical radius ℓ converge to a backward Markov chain on R+. This limiting Markov chain can be explicitly represented in terms of a cascade of subordinators which in turn makes possible a description of the genealogy of the population.
In this paper, we calculate a transaction–based price index for apartments in Paris (France). The heterogeneous character of real estate is taken into account using an hedonic model. The functional form is specified using a general Box–Cox function. The data basis covers 84 686 transactions of the housing market in 1990:01–1999:12, which is one of the largest samples ever used in comparable studies. Low correlations of the price index with stock and bond indices (first differences) indicate diversification benefits from the inclusion of real estate in a mixed asset portfolio. JEL C43, C51, O18, R20.
Japanese is often taken to be strictly head-final in its syntax. In our work on a broad-coverage, precision implemented HPSG for Japanese, we have found that while this is generally true, there are nonetheless a few minor exceptions to the broad trend. In this paper, we describe the grammar engineering project, present the exceptions we have found, and conclude that this kind of phenomenon motivates on the one hand the HPSG type hierarchical approach which allows for the statement of both broad generalizations and exceptions to those generalizations and on the other hand the usefulness of grammar engineering as a means of testing linguistic hypotheses.
A checklist of the mosses (Bryophyta) of the Wet Tropics bioregion, north-east Queensland is presented. Included is an update on the taxonomy of species, listing a total of 408 taxa. The habitat and distribution patterns of species within the area and in Australia, together with information on the phytogeographical affinities of these taxa in related areas beyond Australia, are discussed.
Docherty et alii have "noted that several sociolinguistic accounts have shown a sharp distinction between the social trajectories for glottal replacement as opposed to glottal reinforcement, which have normally been treated by phonologists as aspects of 'the same thing'. It may therefore not always be appropriate to treat the two phenomena as manifestations of a single process or as points on a single continuum (presumably along which speakers move through time). From the speaker’s point of view (as manifested by different patterns of speaker behaviour) they appear as independent phenomena" (1997: 307).
Results of a production experiment on the placement of sentence accent in German are reported. The hypothesis that German fulfills some of the most widely accepted rules of accent assignment— predicting focus domain integration—was only partly confirmed. Adjacency between argument and verb induces a single accent on the argument, as recognized in the literature, but interruption of this sequence by a modifier often induces remodeling of the accent pattern with a single accent on the modifier. The verb is rarely stressed. All models based on linear alignment or adjacency between elements belonging to a single accent domain fail to account for this result. A cyclic analysis of prosodic domain formation is proposed in an optimality-theoretic framework that can explain the accent pattern.
Quantificational determiners in Japanese can be marked with genitive case. Current analyses (for example by Watanabe, Natural Language and Linguistic Theory, to appear) treat the genetive case marker in these cases as semantically vacuous, but we show that it has semantic effects. We propose a new analysis as reverse partitives. Following Jackendoff (MIT-Press, 1977), we assume that partitives always contain two NPs one of which is phonologically deleted. We claim that, while in normal partitives the higher noun is deleted, in reverse partitives the lower noun is deleted.
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.
We discuss gapless colour superconductivity for neutral quark matter in β equilibrium at zero as well as at nonzero temperature. Basic properties of gapless superconductors are reviewed. The current progress and the remaining problems in the understanding of the phase diagram of strange quark matter are discussed.
We have studied the ubiquinone-reducing catalytic core of NADH:ubiquinone oxidoreductase (complex I) from Yarrowia lipolytica by a series of point mutations replacing conserved histidines and arginines in the 49-kDa subunit. Our results show that histidine 226 and arginine 141 probably do not ligate iron-sulfur cluster N2 but that exchanging these residues specifically influences the properties of this redox center. Histidines 91 and 95 were found to be essential for ubiquinone reductase activity of complex I. Mutations at the C-terminal arginine 466 affected ubiquinone affinity and inhibitor sensitivity but also destabilized complex I. These results provide further support for a high degree of structural conservation between the 49-kDa subunit of complex I and its ancestor, the large subunit of water-soluble [NiFe] hydrogenases. In several mutations of histidine 226, arginine 141, and arginine 466 the characteristic EPR signatures of iron-sulfur cluster N2 became undetectable, but specific, inhibitor-sensitive ubiquinone reductase activity was only moderately reduced. As we could not find spectroscopic indications for a modified cluster N2, we concluded that these complex I mutants were lacking most of this redox center but were still capable of catalyzing inhibitor-resistant ubiquinone reduction at near normal rates. We discuss that this at first surprising scenario may be explained by electron transfer theory; after removal of a single redox center in a chain, electron transfer rates are predicted to be still much faster than steady-state turnover of complex I. Our results question some of the central mechanistic functions that have been put forward for iron-sulfur cluster N2.
The transporter associated with antigen processing (TAP) is a key component of the cellular immune system. As a member of the ATP-binding cassette (ABC) superfamily, TAP hydrolyzes ATP to energize the transport of peptides from the cytosol into the lumen of the endoplasmic reticulum. TAP is composed of TAP1 and TAP2, each containing a transmembrane domain and a nucleotide-binding domain (NBD). Here we investigated the role of the ABC signature motif (C-loop) on the functional non-equivalence of the NBDs, which contain a canonical C-loop (LSGGQ) for TAP1 and a degenerate C-loop (LAAGQ) for TAP2. Mutation of the leucine or glycine (LSGGQ) in TAP1 fully abolished peptide transport. However, TAP complexes with equivalent mutations in TAP2 still showed residual peptide transport activity. To elucidate the origin of the asymmetry of the NBDs of TAP, we further examined TAP complexes with exchanged C-loops. Strikingly, the chimera with two canonical C-loops showed the highest transport rate whereas the chimera with two degenerate C-loops had the lowest transport rate, demonstrating that the ABC signature motifs control peptide transport efficiency. All single site mutants and chimeras showed similar activities in peptide or ATP binding, implying that these mutations affect the ATPase activity of TAP. In addition, these results prove that the serine of the C-loop is not essential for TAP function but rather coordinates, together with other residues of the C-loop, the ATP hydrolysis in both nucleotide-binding sites.
The transporter associated with antigen processing (TAP1/2) translocates cytosolic peptides of proteasomal degradation into the endoplasmic reticulum (ER) lumen. A peptide-loading complex of tapasin, major histocompatibility complex class I, and several auxiliary factors is assembled at the transporter to optimize antigen display to cytotoxic T-lymphocytes at the cell surface. The heterodimeric TAP complex has unique N-terminal domains in addition to a 6 + 6-transmembrane segment core common to most ABC transporters. Here we provide direct evidence that this core TAP complex is sufficient for (i) ER targeting, (ii) heterodimeric assembly within the ER membrane, (iii) peptide binding, (iv) peptide transport, and (v) specific inhibition by the herpes simplex virus protein ICP47 and the human cytomegalovirus protein US6. We show for the first time that the translocation pore of the transporter is composed of the predicted TM-(5-10) of TAP1 and TM-(4-9) of TAP2. Moreover, we demonstrate that the N-terminal domains of TAP1 and TAP2 are essential for recruitment of tapasin, consequently mediating assembly of the macromolecular peptide-loading complex.
Fronting a noun phrase changes the focus structure of a sentence. Therefore, it may affect truth conditions, since some operators, in particular quantificational adverbs, are sensitive to focus. However, the position of the quantificational adverb itself, hence its informational status, is usually assumed not to have any semantic effect. In this paper I discuss a reading of some quantificational adverbs, the relative reading, which disappears if the adverb is fronted. I propose that this reading relies not only on focus, but on B-accent (fall-rise intonation) as well. A fronted Q-adverb is usually pronounced with a B-accent; since only one element can be B-accented, this means that the scope of the adverb contains no B-accented material, hence no relative readings. Thus, the effects of fronting range more widely than is usually assumed, and quantificational adverbs are a useful tool with which to investigate these effects.
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.
We point out that during the supernova II type explosion the thermodynamical conditions of stellar matter between the protoneutron star and the shock front correspond to the nuclear liquid–gas coexistence region, which can be investigated in nuclear multifragmentation reactions. We have demonstrated, that neutron-rich hot heavy nuclei can be produced in this region. The production of these nuclei may influence dynamics of the explosion and contribute to the synthesis of heavy elements.
Despite powerful advances in yield curve modeling in the last twenty years, comparatively little attention has been paid to the key practical problem of forecasting the yield curve. In this paper we do so. We use neither the no-arbitrage approach, which focuses on accurately fitting the cross section of interest rates at any given time but neglects time-series dynamics, nor the equilibrium approach, which focuses on time-series dynamics (primarily those of the instantaneous rate) but pays comparatively little attention to fitting the entire cross section at any given time and has been shown to forecast poorly. Instead, we use variations on the Nelson-Siegel exponential components framework to model the entire yield curve, period-by-period, as a three-dimensional parameter evolving dynamically. We show that the three time-varying parameters may be interpreted as factors corresponding to level, slope and curvature, and that they may be estimated with high efficiency. We propose and estimate autoregressive models for the factors, and we show that our models are consistent with a variety of stylized facts regarding the yield curve. We use our models to produce term-structure forecasts at both short and long horizons, with encouraging results. In particular, our forecasts appear much more accurate at long horizons than various standard benchmark forecasts. JEL Code: G1, E4, C5
0. Introduction 1. Observations concerning the structure of morphosyntactically marked focus constructions 1.1 First observation: SF vs. NSF asymmetry 1.2 Second observation: NSF-NAR parallelism 1.3 Affirmative ex-situ focus constructions (SF, NSF), and narrative clauses (NAR) 2. Grammaticalization 2.1 Cleft hypothesis 2.2 Movement hypothesis 2.3 Narrative hypothesis 2.3.1 Back- or Foregrounding? 2.3.2 Converse directionality of FM and conjunction 3. Language specific analysis 4. Conclusionary remarks References
We suggest that the fluctuations of strange hadron multiplicity could be sensitive to the equation of state and microscopic structure of strongly interacting matter created at the early stage of high energy nucleus–nucleus collisions. They may serve as an important tool in the study of the deconfinement phase transition. We predict, within the statistical model of the early stage, that the ratio of properly filtered fluctuations of strange to non-strange hadron multiplicities should have a non-monotonic energy dependence with a minimum in the mixed phase region.
We suggest that the fluctuations of strange hadron multiplicity could be sensitive to the equation of state and microscopic structure of strongly interacting matter created at the early stage of high energy nucleus-nucleus collisions. They may serve as an important tool in the study of the deconfinement phase transition. We predict, within the statistical model of the early stage, that the ratio of properly filtered fluctuations of strange to non-strange hadron multiplicities should have a non-monotonic energy dependence with a minimum in the mixed phase region.
We propose a method to experimentally study the equation of state of strongly interacting matter created at the early stage of nucleus–nucleus collisions. The method exploits the relation between relative entropy and energy fluctuations and equation of state. As a measurable quantity, the ratio of properly filtered multiplicity to energy fluctuations is proposed. Within a statistical approach to the early stage of nucleus–nucleus collisions, the fluctuation ratio manifests a non-monotonic collision energy dependence with a maximum in the domain where the onset of deconfinement occurs.
We propose a method to experimentally study the equation of state of strongly interacting matter created at the early stage of nucleus--nucleus collisions. The method exploits the relation between relative entropy and energy fluctuations and equation of state. As a measurable quantity, the ratio of properly filtered multiplicity to energy fluctuations is proposed. Within a statistical approach to the early stage of nucleus-nucleus collisions, the fluctuation ratio manifests a non--monotonic collision energy dependence with a maximum in the domain where the onset of deconfinement occurs.
A study was undertaken of the floristic patterns in coastal rainforest (low closed forest) of Shoalwater Bay, central Queensland. The site encompasses 60 km of coastline, extending from latitude 22° 08’ 30’’ to 22° 30’ 0” and longitude 150° 02’ 00” to 150° 24’ 30”. The rainforest grows on coastal Holocene sand dunes, swales and sand flats, distributed as a series of 27 discrete patches greater than one hectare along 60 kilometres of coastline. Mean patch size was 10.7 hectares (maximum 150 hectares). The flora was predominantly woody, and lacked the complex growth forms of Webb (1968). Floristic links with central and north Queensland were strong, with some species distributions extending into Malesia and the Pacific. Three physical strata, emergent (composed of trees), canopy (composed of trees, vines and epiphytes) and sub-canopy (trees, vines and herbs) were recognised. The herb layer was very poorly developed. Eighty-one species were recorded, representing 42 families and 72 genera.
Sixty three quadrats were sampled across the rainforest patches to measure abundance of all vascular taxa using frequency score. Five floristic groups were defined from agglomerative classification analysis, one representing mixed forest, two representing low microphyll vine forest (LMVF) and two representing microphyll vine thicket (MVT). The vegetation at the study site was predominantly MVT. Five species groups were defined, one correlated with the mixed forest, one with the LMVF and one with the MVT. The remaining species groups represented ubiquitous and widespread species. Floristic patterns were found to be strongly influenced by three environmental variables using canonical correspondence analysis. The strongest variable was drainage, which separated the mixed forest from the vine forest/thicket. The LMVF/MVT vegetation forms a continuum along an environmental gradient, influenced by exposure to onshore-winds and landform height. The mesic/protected extreme was represented by the tallest LMVF situated in swales, whilst at the exposure/ elevation extreme was represented by wind-sheared MVT located on foredunes.
Floristic patterns along an east–west gradient in grassy box woodlands of Central New South Wales
(2004)
Temperate grassy box woodlands are the predominant native vegetation of the "wheat-sheep" belt of south-eastern Australia. In New South Wales, a number of different eucalypt species form the overstorey of these woodlands, with changes in dominance from Eucalyptus melliodora (Yellow Box) and Eucalyptus albens (White Box) in the east to Eucalyptus microcarpa (Grey Box) and Eucalyptus populnea (Poplar Box) in the west. Most grassy Box woodlands have now been cleared or modified for agriculture, and their conservation is dependent on adequate knowledge of the distribution, ecology and management needs of remaining woodlands. In this study we describe the understorey flora of high quality remnants of grassy Box woodlands along an east-west gradient in central New South Wales, comparing sites with a history of minimal livestock grazing (cemeteries) with sites with a history of intermittent livestock grazing (travelling stock reserves). With some important exceptions relating to Eucalyptus melliodora, dominant overstorey eucalypts were good indicators of understorey changes along the east-west gradient. A particular disjunction, involving changes in the dominant grasses from Themeda australis and Poa sieberiana to Austrostipa scabra, Austrodanthonia and Enteropogon species, distinguishes "eastern" (Eucalyptus melliodora, Eucalyptus albens) from "western" (Eucalyptus microcarpa, Eucalyptus populnea) Box woodlands, and has significant implications for understorey management. Notable changes in subsidiary species included changes in the main genera of shrubs and daisies, and a number of trends at the family level. Families such as Dilleniaceae, Haloragaceae, Epacridaceae and Ranunculaceae were more frequent or diverse in eastern Box woodlands, and gave way to species of the families Malvaceae, Chenopodiaceae, Myoporaceae, Amaranthaceae and Brassicaceae in the west. Intermittent grazing influenced understorey composition in all box woodlands sampled, although influences in western Box woodlands were less pronounced. Effects of grazing included a decline in shrub abundance and loss of a range of native perennials across all woodlands, changes to the dominant grasses and a considerable increase in exotic annuals in the east, and a decline in native grass diversity and increase in native annuals in the west.
Floristic communities from the alluvial floodplains and near-alluvial plains of the lower Dawson River, mideastern Queensland, are described from near-intact sites. Three broad and ten detailed floristic groups were defined. Differences in community composition appeared related to soil type, localised disturbance and latitude. Weeds comprised a small proportion of the total flora, although they presently dominate some areas. Grasses were the main exotic species present, and appeared to have increased within the last forty years.
Montagu Island (36°15’S; 150°14’E) is situated about 10 km east of Narooma on the New South Wales South Coast. The paper presents evidence about the changes in the terrestrial vegetation of the island since it was first seen by Europeans, provides a floristic inventory and gives a perspective on the effects of introduced species.
Flinders (1814) mentions that the island "produced small trees." This is the only record of what grew on the island until in 1880 annotations on a map, made at the time of the construction of the lighthouse, mentioned the presence of scrub, trees and rank grass. This is confirmed by photographic evidence, but by 1932, when the botanist F. A. Rodway visited the island, the trees had disappeared. In 1973, during a land use survey of the South Coast, a team of CSIRO described the vegetation as a distinct series of dune communities belonging to the Lomandra longifolia – Pteridium esculentum – Phragmites australis complex. Vegetation mapping in the late 1980s confirmed the prevalence of these species, except that Pennisetum clandestinum then covered a large area along the west side of the island.
Excluding taxa used for ornamental or culinary purposes, nearly 200 species of vascular plants have been recorded since 1932 of which about 140 were still present in the late 1990s. There are ten species of ferns e.g. Pteridium esculentum, widespread and sometimes codominant with Lomandra longifolia, and Asplenium obtusatum, frequently found among the rocks along the east side of the island. The only taxon unique to Montagu Island is a hybrid of this species and Asplenium australasicum. Among the flowering plants there are about 110 native species and about 70 species naturalised in Australia. About 85 and 40, respectively, are still present today. Many of these have a wide distribution in Australia and only about 25 have a more restricted coastal distribution. The species that have disappeared include many that were weeds in the vegetable gardens or around the chicken sheds. Several naturalised species still present are notorious for their capacity to overrun existing vegetation. Foremost among these is Pennisetum clandestinum, which now covers about one-third of the island; Acetosa sagittata is a close second. Other contenders are Dipogon lignosus and Delairea odorata. It is now apparent that these species were kept in check by the feral goats that roamed the island before it was declared a Nature Reserve in December 1987.
In this paper, I argue that this apparent problem is accounted for by the interaction of constraints. For the fixed segment [ɛ] in Cɛ-reduplication, I argue that [ɛ] is the second least marked vowel in Palauan, which appears when the default vowel [ǝ] cannot appear. I show that the Palauan facts are not only consistent with the proposals of Urbanczyk (1999) and Alderete et. al (1999), but they actually provide support of their claims. In the following section, I discuss Urbanczyk's (1999) arguments concerning ROOT faithfulness in reduplication and possible asymmetries between affix reduplicants and root reduplicants. In Section 3, I introduce Palauan reduplication and discuss Finer's (1986) observations on the resulting state verb (RSV) form. I show that the RSV forms support the classification that Cɛ-reduplicants are affixes, and CVCV -reduplicants are roots. In Section 4, I discuss the shape and vowel quality of the two reduplicants. The CVCV-reduplicant has three variants: CǝCǝ, CǝC and CV. I explain this variation, illustrating why [ǝ] appears in the first two variations. Then, I discuss the shape and vowel quality of the Cɛ-reduplicant, arguing that the fixed segment [ɛ] in Cɛ-reduplication is a special case of TETU. I show that root faithfulness constraints are crucial in determining the shape and vowel quality of the reduplicants. Section 5 is the conclusion.
In fire-prone grassy woodlands, fire response and time to reach reproductive maturity are two traits that can be used to provide an indication of the minimum interval between fires needed to maintain biodiversity. This study examined the effects of fire intensity and adult size on shrub mortality together with the primary and secondary juvenile periods of shrub species in the New England Tableland (NET) Bioregion. Most shrub species resprouted via basal lignotubers following fire, irrespective of fire intensity and shrub size. The primary juvenile period of most species was found to be greater than four years and the secondary juvenile period for most resprouting species was less than four years. These results suggest that a minimal interval between fires of eight years may be needed to maintain shrub species in grassy woodlands in the NET Bioregion, and that repeated fires at intervals of less than 8 years should be avoided. The time taken for shrubs in the grassy woodlands of the NET Bioregion to reach reproductive maturity appears to be longer than conspecifics in other Bioregions. Caution is needed when using data collected from outside a Bioregion to determine minimum fire frequency thresholds.
A widely recognized paper by Colin Mayer (1988) has led to a profound revision of academic thinking about financing patterns of corporations in different countries. Using flow-of-funds data instead of balance sheet data, Mayer and others who followed his lead found that internal financing is the dominant mode of financing in all countries, that financing patterns do not differ very much between countries and that those differences which still seem to exist are not at all consistent with the common conviction that financial systems can be classified as being either bank-based or capital market-based. This leads to a puzzle insofar as it calls into question the empirical foundation of the widely held belief that there is a correspondence between the financing patterns of corporations on the one side, and the structure of the financial sector and the prevailing corporate governance system in a given country on the other side. The present paper addresses this puzzle on a methodological and an empirical basis. It starts by comparing and analyzing various ways of measuring financial structure and financing patterns and by demonstrating that the surprising empirical results found by studies that relied on net flows are due to a hidden assumption. It then derives an alternative method of measuring financing patterns, which also uses flow-of-funds data, but avoids the questionable assumption. This measurement concept is then applied to patterns of corporate financing in Germany, Japan and the United States. The empirical results, which use an estimation technique for determining gross flows of funds in those cases in which empirical data are not available, are very much in line with the commonly held belief prior to Mayer’s influential contribution and indicate that the financial systems of the three countries do indeed differ from one another in a substantial way, and moreover in a way which is largely in line with the general view of the differences between the financial systems of the countries covered in the present paper.
We consider three sets of phenomena that feature prominently - and separately - in the financial economics literature: conditional mean dependence (or lack thereof) in asset returns, dependence (and hence forecastability) in asset return signs, and dependence (and hence forecastability) in asset return volatilities. We show that they are very much interrelated, and we explore the relationships in detail. Among other things, we show that: (a) Volatility dependence produces sign dependence, so long as expected returns are nonzero, so that one should expect sign dependence, given the overwhelming evidence of volatility dependence; (b) The standard finding of little or no conditional mean dependence is entirely consistent with a significant degree of sign dependence and volatility dependence; (c) Sign dependence is not likely to be found via analysis of sign autocorrelations, runs tests, or traditional market timing tests, because of the special nonlinear nature of sign dependence; (d) Sign dependence is not likely to be found in very high-frequency (e.g., daily) or very low-frequency (e.g., annual) returns; instead, it is more likely to be found at intermediate return horizons; (e) Sign dependence is very much present in actual U.S. equity returns, and its properties match closely our theoretical predictions; (f) The link between volatility forecastability and sign forecastability remains intact in conditionally non-Gaussian environments, as for example with time-varying conditional skewness and/or kurtosis.
We modify the concept of LLL-reduction of lattice bases in the sense of Lenstra, Lenstra, Lovasz [LLL82] towards a faster reduction algorithm. We organize LLL-reduction in segments of the basis. Our SLLL-bases approximate the successive minima of the lattice in nearly the same way as LLL-bases. For integer lattices of dimension n given by a basis of length 2exp(O(n)), SLLL-reduction runs in O(n.exp(5+epsilon)) bit operations for every epsilon > 0, compared to O(exp(n7+epsilon)) for the original LLL and to O(exp(n6+epsilon)) for the LLL-algorithms of Schnorr (1988) and Storjohann (1996). We present an even faster algorithm for SLLL-reduction via iterated subsegments running in O(n*exp(3)*log n) arithmetic steps.
Using a normalized CES function with factor-augmenting technical progress, we estimate a supply-side system of the US economy from 1953 to 1998. Avoiding potential estimation biases that have occurred in earlier studies and putting a high emphasis on the consistency of the data set, required by the estimated system, we obtain robust results not only for the aggregate elasticity of substitution but also for the parameters of labor and capital augmenting technical change. We find that the elasticity of substitution is significantly below unity and that the growth rates of technical progress show an asymmetrical pattern where the growth of laboraugmenting technical progress is exponential, while that of capital is hyperbolic or logarithmic.
This paper is concerned with the tagging of spatial expressions in German newspaper articles, assigning a meaning to the expression and classifying the usages of the spatial expression and linking the derived referent to an event description. In our system, we implemented the activation of concepts in a very simple fashion, a concept is activated once (with a cost depending on the item that activated it) and is left activated thereafter. As an example, a city also activates the nodes for the region and the country it is part of, so that cities from one country are chosen over cities from different countries. A test corpus of 12 German newspaper articles was tested regarding several disambiguation strategies. Disambiguation was carried out via a beam search to find an approximately cost-optimal solution for the conflict set of potential grounding candidates for the tagged spatial expression. Test showed that the disambiguation strategies improved accuracy significantly.
This dissertation investigates developments in the performance of J. S. Bach’s music in the second half of the 20th century, as reflected in recordings of the Mass in B Minor, BWV 232. It places particular emphasis on issues relating to concepts of expression through performance. Between the 1950s and the 1980s, most Bach performers shared a partial consensus as to what constitutes expression in performance (e.g., intense sound; wide dynamic range; rubato). Arguments against the application of such techniques to Bach’s works were often linked with the view that his music is more “objective” than later repertoires; or, alternatively, that expressive elements in Bach’s music are self-sufficient, and should be not be intensified in performance. Historically-informed performance (HIP), from the late 1960s onwards, has been characterised by greater attention to the inflection of local details (i.e., individual figures and motifs). In terms of expressive intensity, this led to contradictory results. On the one hand, several HIP performances were characterised by a narrow overall dynamic range, light textures, fast tempi and few contrasts; these performances were often considered lightweight. On the other hand, HIP also promoted renewed interest in the practical application of Baroque theories of musical rhetoric, inspiring performances which projected varied intensity within movements. More recently, traditional means of expression have enjoyed renewed prominence. Ostensibly “romantic” features such as broad legati, long-range crescendi and diminuendi, and organic shaping of movements as wholes have been increasingly adopted by HIP musicians. In order to substantiate the narrative outlined above, the significance of the evidence preserved in sound recordings had to be checked against other sources of information. This dissertation is divided into two main parts. The first part focuses on specific “schools” of prominent Bach performers. Complete recordings of the Mass are examined in relation to the biographical and intellectual backgrounds of the main representatives of these schools, their verbally-expressed views on Bach’s music and on their own role as performers, and their style as documented in recordings of other works. The second part examines the performance history of specific movements within the Mass, comparing the interpretations preserved in sound recordings with relevant verbal analyses and commentaries. The dissertation as a whole therefore combines the resources of reception and performance studies. Beyond its specific historical conclusions concerning Bach performance in the post-war era, it also provides specific insights into Bach’s music, its meaning and its role in contemporary culture.
Ligands of Iron-Sulphur Cluster N2: In this work the ubiquinone reducing catalytic core of NADH:ubiquinone oxidoreductase (complex I) from Y. lipolytica was studied by a series of point mutations replacing conserved histidines or arginines in the 49-kDa subunit. Although the missing 4th ligand of cluster N2 could not be found in the 49-kDa subunit of complex I, it was clearly demonstrated that iron-sulphur cluster N2 resides directly on the interface between the PSST and 49-kDa subunits. The results presented in this work show that residues in the 49-kDa subunit have strong influence on this redox centre and also on catalytic activity. The strong influence of Arg-141 and His-226 residues in 49-kDa subunit on this cluster can be deducted from complete loss of N2 signals in EPR spectra such as in case of mutants H226A and R141A. In the case of mutant H226M the EPR signal from cluster N2 was shifted and cluster N2 even lost the pH dependence of its redox midpoint potential and became more similar to the other so called 'isopotential' clusters. Specifically in the case of mutants R141M and R141K the characteristic signature of cluster N2 became undetectable in EPR spectra. However, specific dNADH:DBQ oxidoreductase activity that could be inhibited with the specific complex I inhibitors DQA and rotenone was not absolutely abolished but rather reduced. These reductions in complex I activity did not correspond to similar reductions in the specific EPR signal of cluster N2 as it was observed in the His-226 mutant series. No indications could be found that these mutations had modified the magnetic properties of cluster N2, resulting in different EPR spectra. From these observations it could be concluded that both mutants R141K and R141M virtually or entirely lack iron-sulphur cluster N2. The rates in complex I activity could be reconciled with electron transfer theory: After removal of a single redox centre in a chain, electron transfer rates are predicted to be still much faster than steady-state turnover of complex I. These results from mutants R141K, R141M and also the result from mutant H226M that protons are being pumped even if the redox midpoint potential of cluster N2 is not pH dependent questions the prominent role in the catalytic mechanism of complex I that has been ascribed to cluster N2. Histidine 91 and 95 were found to be absolutely essential for activity of complex I since in both mutants complex I was fully assembled and artificial NADH:HAR activity was parental whereas complex I specific dNADH:DBQ activity was abolished. The signal from cluster N2 in EPR spectra was parental for all His-91 and -95 mutants. Mutations at the C-terminal arginine 466 affected ubiquinone affinity and inhibitor sensitivity but also destabilised complex I. All these results provide further support for a high degree of structural conservation between the 49-kDa subunit of complex I and the large subunit of water soluble [NiFe] hydrogenases. Remodelling of Human Pathogenic 49-kDa Mutations in Y. lipolytica: Y. lipolytica has been proven a good system for studying complex I properties and thus also for studying defects that occur in humans. In this work pathogenic mutations in the 49-kDa subunit of complex I were recreated and studied. The P232Q mutant showed non-assembly of complex I and this is probably the cause why this mutation was lethal in patients. The mutants R231Q and S416P were parental for the content, artificial and also specific complex I activity, Km for DBQ and IC50 for DQA. From these results we can conclude that these two residues Arg-228 and Ser-413 in mammalian cells have specific structural importance for the 49-kDa subunit even if they are not directly involved in catalytic process.
In this paper, we study the effectiveness of monetary policy in a severe recession and deflation when nominal interest rates are bounded at zero. We compare two alternative proposals for ameliorating the effect of the zero bound: an exchange-rate peg and price-level targeting. We conduct this quantitative comparison in an empirical macroeconometric model of Japan, the United States and the euro area. Furthermore, we use a stylized micro-founded two-country model to check our qualitative findings. We find that both proposals succeed in generating inflationary expectations and work almost equally well under full credibility of monetary policy. However, price-level targeting may be less effective under imperfect credibility, because the announced price-level target path is not directly observable. Klassifikation: E31, E52, E58, E61
We investigate transverse hadron spectra from relativistic nucleus-nucleus collisions which reflect important aspects of the dynamics - such as the generation of pressure - in the hot and dense zone formed in the early phase of the reaction. Our analysis is performed within two independent transport approaches (HSD and UrQMD) that are based on quark, diquark, string and hadronic degrees of freedom. Both transport models show their reliability for elementary pp as well as light-ion (C+C, Si+Si) reactions. However, for central Au+Au (Pb+Pb) collisions at bombarding energies above ~ 5 A.GeV the measured K+- transverse mass spectra have a larger inverse slope parameter than expected from the calculation. Thus the pressure generated by hadronic interactions in the transport models above ~ 5 A.GeV is lower than observed in the experimental data. This finding shows that the additional pressure - as expected from lattice QCD calculations at finite quark chemical potential and temperature - is generated by strong partonic interactions in the early phase of central Au+Au (Pb+Pb) collisions.
Evidence for an exotic S=-2, Q=-2 baryon resonance in proton-proton collisions at the CERN SPS
(2004)
Results of resonance searches in the Xi - pi -, Xi - pi +, Xi -bar+ pi -, and Xi -bar+ pi + invariant mass spectra in proton-proton collisions at sqrt[s]=17.2 GeV are presented. Evidence is shown for the existence of a narrow Xi - pi - baryon resonance with mass of 1.862±0.002 GeV/c2 and width below the detector resolution of about 0.018 GeV/c2. The significance is estimated to be above 4.2 sigma . This state is a candidate for the hypothetical exotic Xi --3/2 baryon with S=-2, I=3 / 2, and a quark content of (dsdsu-bar). At the same mass, a peak is observed in the Xi - pi + spectrum which is a candidate for the Xi 03/2 member of this isospin quartet with a quark content of (dsusd-bar). The corresponding antibaryon spectra also show enhancements at the same invariant mass.
Event-by-event fluctuations of particle ratios in central Pb + Pb collisions at 20 to 158 AGeV
(2004)
In the vicinity of the QCD phase transition, critical fluctuations have been predicted to lead to non-statistical fluctuations of particle ratios, depending on the nature of the phase transition. Recent results of the NA49 energy scan program show a sharp maximum of the ratio of K+ to Pi+ yields in central Pb+Pb collisions at beam energies of 20-30 AGeV. This observation has been interpreted as an indication of a phase transition at low SPS energies. We present first results on event-by-event fluctuations of the kaon to pion and proton to pion ratios at beam energies close to this maximum.
This paper evaluates the effects of Public Sponsored Training in East Germany in the context of reiterated treatments. Selection bias based on observed characteristics is corrected for by applying kernel matching based on the propensity score. We control for further selection and the presence of Ashenfelter's Dip before the program with conditional difference-in-differences estimators. Training as a first treatment shows insignificant effects on the transition rates. The effect of program sequences and the incremental effect of a second program on the reemployment probability are insignificant. However, the incremental effect on the probability to remain employed is slightly positive. JEL - Klassifikation: H43 , C23 , J6 , J64 , C14
In this study, we develop a technique for estimating a firm’s expected cost of equity capital derived from analyst consensus forecasts and stock prices. Building on the work of Gebhardt/Lee/-Swaminathan (2001) and Easton/Taylor/Shroff/Sougiannis (2002), our approach allows daily estimation, using only publicly available information at that date. We then estimate the expected cost of equity capital at the market, industry and individual firm level using historical German data from 1989-2002 and examine firm characteristics which are systematically related to these estimates. Finally, we demonstrate the applicability of the concept in a contemporary case study for DaimlerChrysler and the European automobile industry.
his Erratum replaces incorrect plots shown in Fig. 7 with the corrected ones. In the publication, the NA57 [1] ratios of Ξ− and Ξ¯¯¯¯+ to the number of wounded nucleons at ⟨NW⟩=349 by mistake were plotted at the wrong values. The ratios were calculated and plotted by mistake using ⟨NW⟩=249.
The correct normalization does not change the conclusions of the paper. The correctly normalized results are presented in Fig. 7.
FGF-2, a potent multifunctional and neurotrophic growth factor, is widely expressed in the brain and upregulated in cerebral ischemia. Previous studies have shown that intraventricularly or systemically administered FGF-2 reduces the size of cerebral infarcts. Whether endogenous FGF-2 is beneficial for the outcome of cerebral ischemia has not been investigated. We have used mice with a null mutation of the fgf2 gene to explore the relevance of endogenous FGF-2 in brain ischemia. Focal cerebral ischemia was produced by occlusion of the middle cerebral artery (MCAO). We found a 75% increase in infarct volume in fgf2 knock-out mice versus wild type littermates (P < 0.05). This difference in the extent of ischemic damage was observed after 24 h, and correlated with decreased viability in fgf2 mutant mice following MCA occlusion. Increased infarct volume in fgf2 null mice was associated with a loss of induction in hippocampal BDNF and trkB mRNA expression. These findings indicate that signaling through trkB may contribute to ameliorating brain damage following ischemia and that bdnf and trkB may be target genes of FGF-2. Together, our data provide the first evidence that endogenous FGF-2 is important in coping with ischemic brain damage suggesting fgf2 as one crucial target gene for new therapeutic strategies in brain ischemia.
The present study offers an Optimality-Theoretic analysis of the syllabification of intervocalic consonants and glides in Modern English. It will be argued that the proposed syllabifications fall out from universal markedness constraints – all of which derive motivation from other languages – and a language-specific ranking. The analysis offered below is therefore an alternative to the traditional rule-based analyses of English syllabification, e.g. Kahn (1976), Borowsky (1986), Giegerich (1992, 1999) and to the Optimality-Theoretic treatment proposed by Hammond (1999), whose analysis requires several language-specific constraints which apparently have no cross-linguistic motivation.
The data on mT spectra of K0S K+ and K- mesons produced in all inelastic p + p and p + pbar interactions in the energy range sqrt(s)NN=4.7-1800GeV are compiled and analyzed. The spectra are parameterized by a single exponential function, dN/(m_T*dm_T)=C exp(-m_T/T), and the inverse slope parameter T is the main object of study. The T parameter is found to be similar for K0S, K+ and K- mesons. It increases monotonically with collision energy from T~30MeV at sqrt(s)NN=4.7GeV to T~220MeV at sqrt(s)NN=1800GeV. The T parameter measured in p+p and p+pbar interactions is significantly lower than the corresponding parameter obtained for central Pb+Pb collisions at all studied energies. Also the shape of the energy dependence of T is different for central Pb+Pb collisions and p+p(pbar) interactions.
The transverse mass mt distributions for deuterons and protons are measured in Pb+Pb reactions near midrapidity and in the range 0<mt–m<1.0 (1.5) GeV/c2 for minimum bias collisions at 158A GeV and for central collisions at 40 and 80 A GeV beam energies. The rapidity density dn/dy, inverse slope parameter T and mean transverse mass <mt> derived from mt distributions as well as the coalescence parameter B2 are studied as a function of the incident energy and the collision centrality. The deuteron mt spectra are significantly harder than those of protons, especially in central collisions. The coalescence factor B2 shows three systematic trends. First, it decreases strongly with increasing centrality reflecting an enlargement of the deuteron coalescence volume in central Pb+Pb collisions. Second, it increases with mt. Finally, B2 shows an increase with decreasing incident beam energy even within the SPS energy range. The results are discussed and compared to the predictions of models that include the collective expansion of the source created in Pb+Pb collisions.
A small electrostatic storage ring is the central machine of the Frankfurt Ion Storage Experiments (FIRE) which will be built at the new Stern-Gerlach Center of Frankfurt University. As a true multiuser, multipurpose facility with ion energies up to 50 keV, it will allow new methods to analyze complex many-particle systems from atoms to very large biomolecules. With envisaged storage times of some seconds and beam emittances in the order of a few mm mrad, measurements with up to 6 orders of magnitude better resolutions as compared to single-pass experiments become possible. In comparison to earlier designs, the ring lattice was modified in many details: Problems in earlier designs were related to, e.g., the detection of light particles and highly charged ions with different charge states. Therefore, the deflectors were redesigned completely, allowing a more flexible positioning of the diagnostics. Here, after an introduction to the concept of electrostatic machines, an overview of the planned FIRE is given and the ring lattice and elements are described in detail.
Results are presented on event-by-event electric charge fluctuations in central Pb+Pb collisions at 20, 30, 40, 80 and 158 AGeV. The observed fluctuations are close to those expected for a gas of pions correlated by global charge conservation only. These fluctuations are considerably larger than those calculated for an ideal gas of deconfined quarks and gluons. The present measurements do not necessarily exclude reduced fluctuations from a quark-gluon plasma because these might be masked by contributions from resonance decays.
Editorial
(2004)
The question whether the adoption of International Financial Reporting Standards (IFRS) will result in measurable economic benefits is of special policy relevance in particular given the European Union’s decision to require the application of IFRS by listed companies from 2005/2007. In this paper, I investigate the common con-jecture that internationally recognized high quality reporting standards (IAS/IFRS or US-GAAP) reduce the cost of capital of adopting firms (e.g. Levitt 1998; IASB 2002). Building on Leuz/Verrecchia (2000), I use a set of German firms which pre-adopted such standards before 2005, but investigate the potential economic benefits by analyzing their expected cost of equity capital utilizing and customizing avail-able implied estimation methods (e.g. Gebhardt/Lee/Swaminathan 2001, Easton/Taylor/Shroff/Sougiannis 2002, Easton 2004). Evidence from a sample of about 13,000 HGB, 4,500 IAS/IFRS and 3,000 US-GAAP firm-month observations in the period 1993-2002 generally fails to document lower expected cost of equity capital and therefore measurable economic benefits for firms applying IAS/IFRS or US-GAAP. Accordingly, I caution to state that reporting under internationally accepted standards, per se, lowers the cost of equity capital of adopting firms.
We propose a new framework for modelling the time dependence in duration processes being in force on financial markets. The pioneering ACD model introduced by Engle and Russell (1998) will be extended in a manner that the duration process will be accompanied by an unobservable stochastic process. The Discrete Mixture ACD framework provides us with a general methodology which puts the idea into practice. It is established by introducing a discrete-valued latent regime variable which can be justified in the light of recent market microstructure theories. The empirical application demonstrates its ability to capture specific characteristics of intraday transaction durations while alternative approaches fail. JEL classification: C41, C22, C25, C51, G14.
This work examines English echo questions (EQs) against the background of Rizzi's (1997) analysis of split CP. It argues that EQs do not behave as the split CP analysis predicts that they should, and that their behavior can instead be straightforwardly explained within the classic CP analysis. Further, what are termed here 'echo negations' of negative inversion constructions are shown not to parallel EQs, a surprising result if negative inversion architecture parallels question architecture, as claimed by split CP proponents. In general, classic CP architecture is more appropriate for analysing this range of phenomena.
Subalpine shrubs on rocky slopes on the Bogong High Plains, Victoria (36° 53’ S, 147° 19’ E), were observed to be severely desiccated over the summer of 2002/03 after a 50 day period when only 1.2 mm of rainfall was recorded. Moderate to severe canopy dieback was noted in shrubs growing on rocky north- and west-facing slopes. Four shrubs were assessed for their drought tolerance on west-facing slopes at Basalt Hill. Soils were rocky and uniformly shallow across the site (mean depth = 11.32 ± 0.69 cm). Prostanthera cuneata was the most drought tolerant species (as evidenced by the least amount of canopy dieback observed) followed by Hovea montana, Pimelea axiflora var. alpina and Epacris glacialis. All Epacris glacialis plants (n = 16) had died at the study location whereas no Prostanthera cuneata plants (n = 45) had canopy dieback that exceeded 60%. The amount of dieback observed was not significantly associated with either local soil depth or shrub canopy area. Hence, very small plants were not more susceptible to drought nor were shrubs found on the shallowest of the soils at the site. This suggests that drought effects are possibly dependent on local influences such as topography, drainage and competition intensity. Drought has only rarely been considered a major factor affecting the abundance and distribution of subalpine shrub species in Australia but this study suggests that it should be added to the list of abiotic factors governing the local dynamics of subalpine vegetation. In particular, the high mortality of Epacris glacialis observed in the study area suggests that non-equilibrium dynamics are likely to be the "norm" for some shrubs in subalpine areas.
65 species of Odonata are recorded from Mulanje and its slopes. Only eight species dominate on the high plateau. Among them are two relict species of conservation concern: The endemic Oreocnemis phoenix (monotypic genus) and the restricted-range species Chlorolestes elegans. The absence of mountain marsh specialists on the plateau is noteworthy. Mulanje’s valleys, of which Likabula and Ruo are best known, have a rich dragonfly fauna. The Eastern Arc relict Nepogomphoides stuhlmanni is common here.
The purpose of this research was to trace the developmental steps in the acquisition of aspectual oppositions in Russian and to examine the validity of the 'aspect before tense' hypothesis for L1-speaking children. Imperfective/perfective verbs and their inflections, as well as aspectual pairs, were analysed in the first five months of verb production (and the respective months in the input) in three children. Additionally, the first four months of verb production were investigated in one boy with less data. Verb forms marked for the past and for the present occur simultaneously in all children. These early forms relate to 'here and now' situations: verbs marked for the past denote 'resultative' events that are perceived by the children as occurring during the speech time or immediately before it, while verbs marked for the present typically denote on-going events. Thus, with early tense oppositions (or tense morphology) children mark aspectual contrasts in the moment of speech: evidence in favour of the 'aspect before tense' hypothesis.
A strong preference in using the perfective aspect for the past and the imperfective aspect for the present events has been found in both adults and children. Further, only very few aspectual pairs were documented within the analysed period (from the onset of verb production to the period when children produce rule-driven inflectional forms). The productive use of the finite forms of perfective and imperfective verbs doesn't concord with the ability of the productive use of the contrastive forms of one lemma. Data suggest that children (start to) learn aspectual forms in an item-based manner. The acquisition of aspectual oppositions (aspectual pairs) is lexically dependent and is guided by the contextual 'thesaurus'. Aspectual pairs are learned in a peace-meal way during much longer, than observed for this article, period of time. Generally, aspect is not learned as a rule, also because there are no (uniform) rules of forming of aspectual pairs, but as the 'satellite' of the inherent lexical meaning of verbs of diverse Aktionsarten.
The issues addressed here are relevant for other Slavic languages, exhibiting the morphological category of aspect.