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DCD – a novel plant specific domain in proteins involved in development and programmed cell death
(2005)
Background: Recognition of microbial pathogens by plants triggers the hypersensitive reaction, a common form of programmed cell death in plants. These dying cells generate signals that activate the plant immune system and alarm the neighboring cells as well as the whole plant to activate defense responses to limit the spread of the pathogen. The molecular mechanisms behind the hypersensitive reaction are largely unknown except for the recognition process of pathogens. We delineate the NRP-gene in soybean, which is specifically induced during this programmed cell death and contains a novel protein domain, which is commonly found in different plant proteins.
Results: The sequence analysis of the protein, encoded by the NRP-gene from soybean, led to the identification of a novel domain, which we named DCD, because it is found in plant proteins involved in d evelopment and c ell d eath. The domain is shared by several proteins in the Arabidopsis and the rice genomes, which otherwise show a different protein architecture. Biological studies indicate a role of these proteins in phytohormone response, embryo development and programmed cell by pathogens or ozone.
Conclusion: It is tempting to speculate, that the DCD domain mediates signaling in plant development and programmed cell death and could thus be used to identify interacting proteins to gain further molecular insights into these processes.
Background: Osteoarthritis (OA) has a high prevalence in primary care. Conservative, guideline orientated approaches aiming at improving pain treatment and increasing physical activity, have been proven to be effective in several contexts outside the primary care setting, as for instance the Arthritis Self management Programs (ASMPs). But it remains unclear if these comprehensive evidence based approaches can improve patients' quality of life if they are provided in a primary care setting. Methods/Design: PraxArt is a cluster randomised controlled trial with GPs as the unit of randomisation. The aim of the study is to evaluate the impact of a comprehensive evidence based medical education of GPs on individual care and patients' quality of life. 75 GPs were randomised either to intervention group I or II or to a control group. Each GP will include 15 patients suffering from osteoarthritis according to the criteria of ACR. In intervention group I GPs will receive medical education and patient education leaflets including a physical exercise program. In intervention group II the same is provided, but in addition a practice nurse will be trained to monitor via monthly telephone calls adherence to GPs prescriptions and advices and ask about increasing pain and possible side effects of medication. In the control group no intervention will be applied at all. Main outcome measurement for patients' QoL is the GERMAN-AIMS2-SF questionnaire. In addition data about patients' satisfaction (using a modified EUROPEP-tool), medication, health care utilization, comorbidity, physical activity and depression (using PHQ-9) will be retrieved. Measurements (pre data collection) will take place in months I-III, starting in June 2005. Post data collection will be performed after 6 months. Discussion: Despite the high prevalence and increasing incidence, comprehensive and evidence based treatment approaches for OA in a primary care setting are neither established nor evaluated in Germany. If the evaluation of the presented approach reveals a clear benefit it is planned to provide this GP-centred interventions on a much larger scale.
A systematic analysis of data on strangeness and pion production in nucleon–nucleon and central nucleus–nucleus collisions is presented. It is shown that at all collision energies the pion/baryon and strangeness/pion ratios indicate saturation with the size of the colliding nuclei. The energy dependence of the saturation level suggests that the transition to the Quark Gluon Plasma occurs between 15 A·GeV/c (BNL AGS) and 160 A·GeV/c (CERN SPS) collision energies. The experimental results interpreted in the framework of a statistical approach show that the effective number of degrees of freedom increases in the course of the phase transition and that the plasma created at CERN SPS energies may have a temperature of about 280 MeV (energy density ~ 10 GeV/fm exp-3). The presence of the phase transition can lead to the non–monotonic collision energy dependence of the strangeness/pion ratio. After an initial increase the ratio should drop to the characteristic value for the QGP. Above the transition region the ratio is expected to be collision energy independent. Experimental studies of central Pb+Pb collisions in the energy range 20–160 A·GeV/c are urgently needed in order to localize the threshold energy, and study the properties of the QCD phase transition.
Von den Konflikten auf dem Weg zum guten und schlechten Menschen : 2. Wie lernt man, kalt zu werden?
(1997)
Vortrag an der "Die Lebendigkeit kritischer Gesellschaftstheorie", einer Arbeitstagung aus Anlass des 100. Geburtstages von Theodor W. Adorno, die am 4. - 6. Juli 2003 an der Johann Wolfgang Goethe-Universität in Frankfurt am Main statfand. Koordiniert von Prof. Dr. Andreas Gruschka und Prof. Dr. Ulrich Oevermann. Die Tagungsbeiträge können auch auf CD (je CD ein Vortrag) oder als DVD (alle Vorträge im MP3-Format) käuflich erworben werden. S.a. "Die Lebendigkeit der kritischen Gesellschaftstheorie", herausgegeben von Andreas Gruschka und Ulrich Oevermann. Dokumentation der Arbeitstagung aus Anlass des 100. Geburtstages von Theodor W. Adorno. Büchse der Pandora 2004, ISBN 3-88178-324-5
For investigation of space charge compensation process due to residual gas ionization and the experimentally study of the rise of compensation, a Low Energy Beam Transport (LEBT) system consisting of an ion source, two solenoids, a decompensation electrode to generate a pulsed decompensated ion beam and a diagnostic section was set up. The potentials at the beam axis and the beam edge were ascertained from time resolved measurements by a residual gas ion energy analyzer. A numerical simulation of self-consistent equilibrium states of the beam plasma has been developed to determine plasma parameters which are difficult to measure directly. The temporal development of the kinetic and potential energy of the compensation electrons has been analyzed by using the numerically gained results of the simulation. To investigate the compensation process the distribution and the losses of the compensation electrons were studied as a function of time. The acquired data show that the theoretical estimated rise time of space charge compensation neglecting electron losses is shorter than the build up time determined experimentally. To describe the process of space charge compensation an interpretation of the achieved results is given.
Investigation of the focus shift due to compensation process for low energy ion beam transport
(2000)
In magnetic Low Energy Beam Transport (LEBT) sections space charge compensation helps to enhance the transportable beam current and to reduce emittance growth due to space charge forces. For pulsed beams the time neccesary to establish space charge compensation is of great interest for beam transport. Particularly with regard to beam injection into the first accelerator section (e.g. RFQ) investigation of effects on shift of the beam focus due to space charge compensation are very important. The achieved results helps to obviate a mismatch into the first RFQ. To investigate the space charge compensation due to residual gas ionization, time resolved measurements using pulsed ion beams were performed at the LEBT system at the IAP and at the CEA-Saclay injektion line. A residual gas ion energy analyser (RGIA) equiped with a channeltron was used to measure the potential destribution as a function of time to estimate the rise time of compensation. For time resolved measurements (delta t min=50ns) of the radial density profile of the ion beam a CCD-camera was applied. The measured data were used in a numerical simulation of selfconsistant eqilibrium states of the beam plasma [1] to determine plasma parameters such as the density, the temperature, the kinetic and potential energy of the compensation electrons as a function of time. Measurements were done using focused proton beams (10keV, 2mA at IAP and 92keV, 62mA at CEA-Saclay) to get a better understanding of the influence of the compensation process. An interpretation of the acquired data and the achieved results will be presented.
Influence of space charge fluctuations on the low energy beam transport of high current ion beams
(2000)
For future high current ion accelerators like SNS, ESS or IFMIF the beam behaviour in low energy beam transport sections is dominated by space charge forces. Therefore space charge fluctuations (e. g. source noise) can drastically influence the beam transport properties of the low energy beam transport section. Losses of beam ions and emittance growth are the most severe problems. For electrostatic transport systems either a LEBT design has to be found which is insensitive to variations of the space charge or the origin of the fluctuations has to be eliminated. For space charge compensated transport as proposed for ESS and IFMIF the situation is different: No major influence on beam transport is expected for fluctuations below a cut-off frequency given by the production rate of the compensation particles. Above this frequency the fluctuations can not be compensated by particle production alone, but redistributions of the compensation particles helps to compensate the influence of the fluctuations. Above a second cut-off frequency given by the density and the temperature of the compensation particles their redistribution is too slow to reduce the influence of the space charge fluctuations. Transport simulations for the IFMIF injector including space charge fluctuations will be presented together with a determination of the cut-off frequencies. The results will be compared with measurements of the rise time of space charge compensation.
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.
First results on the production of Xi- and Anti-xi hyperons in Pb+Pb interactions at 40 A GeV are presented. The Anti-xi/Xi- ratio at midrapidity is studied as a function of collision centrality. The ratio shows no significant centrality dependence within statistical errors; it ranges from 0.07 to 0.15. The Anti-xi/Xi- ratio for central Pb+Pb collisions increases strongly with the collision energy.
High perveance negative ion beams with low emittance are essential for several next generation particle accelerators (i. g. spallation sources like ESS [1] and SNS [2]). The extraction and transport of these beams have intrinsic difficulties different from positive ion beams. Limitation of beam current and emittance growth have to be avoided. To fulfill the requirements of those projects a detailed knowledge of the physics of beam formation the interaction of the H- with the residual gas and transport is substantial. A compact cesium free H- volume source delivering a low energy high perveance beam (6.5 keV, 2.3 mA, perveance K= 0.0034) has been built to study the fundamental physics of beam transport and will be integrated into the existing LEBT section in the near future. First measurements of the interaction between the ion beam and the residual gas will be presented together with the experimental set up and preliminary results.
A LEBT system consisting of an ion source, two solenoids, and a diagnostic section has been set up to investigate the space charge compensation process due to residual gas ionization [1] and to study experimentally the rise of compensation. To gain the radial beam potential distribution time resolved measurements of the residual gas ion energy distribution were carried out using a Hughes Rojanski analyzer [2,3]. To measure the radial density profile of the ion beam a CCD-camera performed time resolved measurements, which allow an estimation the rise time of compensation. Further the dynamic effect of the space charge compensation on the beam transport was shown. A numerical simulation under assumption of selfconsistent states [4] of the beam plasma has been used to determine plasma parameters such as the radial density profile and the temperature of the electrons. The acquired data show that the theoretical estimated rise time of space charge compensation neglecting electron losses is shorter than the build up time determined experimentally. An interpretation of the achieved results is given.
To fulfil the requirements of ESS on beam transmission and emittance growth a detailed knowledge of the physics of beam formation as well as the interaction of the H- with the residual gas is substantial. Space charge compensated beam transport using solenoids for ion optics is in favour for the Low Energy Beam Transport (LEBT) between ion source and the first RFQ. Space charge compensation reduces the electrical self fields and beam radii and therefore emittance growth due to aberrations and redistribution. Transport of H- near the ion source is negatively influenced by the dipole fields required for beam extraction and e--dumping and the high gas pressure. The destruction of the rotational symmetry together with the space charge forces causes emittance growth and particle losses within the extraction system. High residual gas pressure near the extractor together with the high cross section for stripping will influence the transmission as well as space charge compensation. Therefore a detailed knowledge of the interaction of the residual gas with the beam and the influence of the external fields on the distribution of the compensation particles is necessary to reduce particle losses and emittance growth. Preliminary experiments using positive hydrogen ions for reference already show the influence of dipole fields on beam emittance. First measurements with H- confirm these results. Additional information on the interactions of the residual gas with the beam ions have been gained from the measurements using the momentum and energy analyser.
Excitation functions for quasi-elastic scattering have been measured at backward angles for the systems 32,34S+197Au and 32,34S+208Pb for energies spanning the Coulomb barrier. Representative distributions, sensitive to the low energy part of the fusion barrier distribution, have been extracted from the data. For the fusion reactions of 32,34S with 197Au couplings related to the nuclear structure of 197Au appear to be dominant in shaping the low energy part of the barrier distibution. For the system 32S+208Pb the barrier distribution is broader and extends further to lower energies, than in the case of 34S+208Pb. This is consistent with the interpretation that the neutron pick-up channels are energetically more favoured in the 32S induced reaction and therefore couple more strongly to the relative motion. It may also be due to the increased collectivity of 32S, when compared with 34S.
S.a. Deutsche Fassung: Ökonomie der Gabe - Positivität der Gerechtigkeit: Gegenseitige Heimsuchungen von System und différance. In: Albrecht Koschorke und Cornelia Vismann (Hg.) System - Macht - Kultur: Probleme der Systemtheorie. Akademie, Berlin 1999, 199-212. Auch auf unserem Server vorhanden. * Italienische Fassung: Economia del dono, positività della giustizia: la reciproca paranoia di Jacques Derrida e Niklas Luhmann. Sociologia e politiche sociali 6, 2003, 113-130. Portugiesische Fassung: Economia da dádiva ? posividade da rustica; ?assombracao?? mutua entre sistema e différance. In: Gunther Teubner, Direito, Sistema, Policontexturalidade, Editora Unimep, Piracicaba Sao Paolo, Brasil 2005, 55-78.
Plus de la moitié des Européens de l’U.E. parlent une langue romane comme langue maternelle. Parmi les autres Européens, l’apprentissage de langues romanes comme langue étrangère est très fréquent, il n’est dépassé que par l’anglais: Une «Romanophonie» pourrait s’appuyer donc sur une base large, tandis que ses valeurs intercompréhensives ne sont pas encore suffisamment mises à la disposition d’un publique européen. Au contraire: les nations créent de plus en plus des barrières entre les langues romanes en institutionnalisant les différences et non pas ce qu’elles ont en commun. En Allemagne où l’on trouve encore la philologie romane (Romanische Philologie) comme unité d’études on peut observer en même temps une tendance vers une spécialisation en études unilingues (Einzelphilologien). Un tel séparatisme linguistique à l’intérieur d’une seule famille renonce aux avantages intercommunicatifs et intercompréhensifs offerts par les langues romanes. Le phénomène de l’intercompréhension est largement connu, pas seulement parmi les romanistes. C’est le résultat d’une tradition de l’écrit et d’un héritage culturel - une partie importante de l’unité intellectuelle du continent européen - qui rend les langues romanes si accessibles. ...
Der sprachfamilienbezogene Erwerb einer L3 bis Lx hat durch die jüngeren sprachpolitischen Forderungen der Europäischen Kommission 1997 entscheidenden Auftrieb erhalten. Im Livre Blanc sur l´éducation et la formation von 1995 bilanziert die Europäische Kommission das Ergebnis der fremdsprachlichen Bemühungen der großen Flächenstaaten der Union als eher kümmerlich und fordert eine Wende. Künftig soll eine Europäische Mehrsprachigkeit drei Perspektiven aufweisen: eine differenzierte Betrachtung von Kompetenzen (rezeptive Mehrsprachigkeit), die Ermöglichung des gezielten Erwerbs von Teilkompetenzen mit modularen Aufbaumöglichkeiten (fachsprachlicher approach zur rezeptiven Lesekompetenz) und das Nutzen der Verwandtschaftsbeziehungen zwischen Sprachen (u.a. romanische Interkomprehensionsforschung). Diese drei Perspektiven werden in dem dreigliedrigen Projekt zur "Eurocomprehension" der Universität Frankfurt zusammengefaßt. Der Frankfurter Beitrag bezieht sich auf die Gruppe der romanischen Sprachen. ...
Rezeptive Mehrsprachigkeit ist eine der jüngsten Forderungen der EU-Kommission zum Erreichen einer realistischen Mehrsprachigkeit in Europa. Die maximalistischen Forderungen nach Perfektion in allen sprachlichen Kompetenzen haben sich in den nationalen Unterrichtswesen als illusionär erwiesen, da diese nirgendwo von statistisch nachvollziehbarem Erfolg gekrönt sind. Die sprachliche Diversität im multilingualen Europa findet sich nicht in der Realität der Bildungssysteme wieder. Zwar verfügen heute europaweit 26 % der Europäer über eine zweite und 8% über eine dritte Fremdsprache, in den einzelnen Ländern sieht es jedoch oft desolat aus. Während in den kleineren Unionsländern kaum jemand als nur monolingual gilt (Luxemburg 2%) ist die Krankheit der Einsprachigkeit in den großen EU-Staaten seuchenhaft verbreitet, etwa Großbritannien mit 66%. Dies hat in den neunziger Jahren in der Kommission zu den Postulaten geführt, die sich die Forschergruppe EuroCom als Programm gesetzt hat, nämlich Mehrsprachigkeit über den Einstieg in rezeptive Kompetenzen modularisiert und kognitiv über Transferbasen innerhalb von Sprachfamilien zu erreichen. EuroCom steht dabei als Kürzel für Eurocomprehension, ein Akronym für Europäische Interkomprehension in den drei großen Sprachengruppen Europas, der romanischen, slawischen und germanischen. Die Beschränkung auf rezeptive Kompetenzen ist dabei nur ein methodisches Ausgangsprinzip, das es ermöglicht, Mehrsprachigkeit besonders schnell über das Leseverständnis zu erreichen und modularisiert auf Hörverständnis und aktive Sprechkompetenz sukzessiv auszuweiten. Die Methode EuroCom arbeitet über die Aktivierung intralingualen Wissens mit linguistischem Transfermaterial in nahverwandten Sprachen, das als kognitives Potential den Erschließungsprozess optimiert und in kürzester Zeit ein Lese- und Hörverstehen in einer ganzen Sprachenfamilie erreichbar macht. ...
Wissenschafts- und Kulturinstitutionen, Bibliotheken und Archive haben heute nicht nur neue Medien zu erwerben, sondern sie stehen auch vor der Aufgabe, das bereits vorhandene Kulturgut auf Dauer zu erhalten. Die Beseitigung von Schäden durch Papierzerfall ist hier nur ein Beispiel. Bei der Rettung historischen Kulturguts ist die Deutsche Forschungsgemeinschaft -neben anderen Institutionen - ein verlässlicher Partner. Ebenso wie beispielsweise die VW-Stiftung unterstützt sie zahlreiche Restaurierungs-, Sicherheitsverfilmungs- und Digitalisierungsvorhaben in den Bereichen Kultur und Wissenschaft. Ich möchte nunmehr versuchen, die Bedeutung der sog. Bestandserhaltung für unser kulturelles Gedächtnis durch sieben kurze Bemerkungen schlaglichtartig zu bestimmen: Diese Bemerkungen tragen die Überschriften: 1) Bibliotheken und Wissenschaft, 2) Bestandserhaltung hat heute Konjunktur, 3) Tontafeln, saure Bücher, Tonbänder und digitale Datenträger, 4) Einige praktische Aspekte des Bestandsschutzes beim traditionellen Buchgut, 5) Sicherheitsverfilmung und Digitalisierung in Archiven und Bibliotheken, 6) Bestandserhaltung, Marketing, Öffentlichkeitsarbeit und 7) Bestandserhaltung in der Wissenschaftsstadt Frankfurt und die "Aktion Notbuch" der Stadt- und Universitätsbibliothek Frankfurt a. M. Zum Artikel: Stand: Januar 2002
Englische Fassung: Societal Constitutionalism: Alternatives to State-centred Constitutional theory? ("Storrs Lectures 2003/04" Yale Law School) In: Christian Joerges, Inge-Johanne Sand und Gunther Teubner (Hg.) Constitutionalism and Transnational Governance. Hart, Oxford 2004, 3-28. Und in: Ius et Lex 2004, S.31-50. Französische Fassung: Constitutionalisme sociétal et globalisation: Alternatives à la théorie constitutionelle centrée sur l'État. Themis 2005 (im Erscheinen) Italienische Fassung: Costituzionalismo societario: alternative alla teoria costituzionale stato-centrica. In: Gunther Teubner, Costituzionalismo societario. Armando, Roma 2005 (im Erscheinen). Spanische Fassung: Globalización y constitucionalismo social: alternativas a la teoría constitucionalista centrada en el Estado". In: Carlos Gómez-Jara Díez (Hg.), Teoría de sistemas y Derecho penal: Fundamentos y posibilidades de aplicación. Granada: Comares, 2005 (im Erscheinen) und in: Cancio Meliá und Bacigalupo Saggese (Hg.) Derecho penal y política transnacional. Barcelona: Atelier, 2005 (in Erscheinen)und in: Gunther Teubner, El Derecho como sistema autopoiético de la sociedad global, herausgegeben von Carlos Gómez-Jara Diez. Bogotá: Universidad Externado de Colombia, 2005 (im Erscheinen) und Lima: ARA Editores, 2005 (im Erscheinen) Polnische Fassung: Konstytucjonalizm spoleczny: Alternatywy dla teorii konstitucyjnej nakierowanej na panstwo. Ius et Lex 3, 2004, S.5-27.
Das Recht hybrider Netzwerke
(2001)
Englische Fassung: Hybrid Laws: Constitutionalizing Private Governance Networks. In: Robert Kagan and Kenneth Winston (Hg.) Legality and Community: On the Intellectual Legacy of Philip Selznick. Berkeley, Berkeley Public Policy Press 2002, 311-331. Italienische Fassung: Diritti ibridi: la costituzionalizzazione delle reti private di governance. In: Gunther Teubner, Costituzionalismo societario. Armando, Roma 2004 (im Erscheinen).
Die Deutsche Kolonialgesellschaft (DKG) war mit ihren bis zu 42.000 Mitgliedern der größte und einflußreichste Interessenverband der deutschen Kolonialbewegung. Sie bestand, wenn auch seit 1933 dem Reichskolonialbund eingegliedert, von 1882 bis 1943. Bisher wurde erst ein Teil unserer Sammlung verfilmt und im Detail gesichtet - die wissenschaftliche Erschließung ist Zukunftsmusik. Dank der Unterstützung durch die Deutsche Forschungs- gemeinschaft, die Marga- und Kurt-Möllgaard-Stiftung und die Adolf-Messer-Stiftung ließ sich jedoch inzwischen wenigstens ein solides Fundament legen. Die Stadt- und Universitätsbibliothek Frankfurt am Main wird bemüht sein, ihre wohl einzigartige kulturhistorische Bildsammlung der deutschen Kolonialaktivitäten, der ein hoher wissenschaftlicher Rang zukommen dürfte, in absehbarer Zeit wieder vollständig verfügbar machen zu können.
Englische Fassung: Global Bukowina: Legal Pluralism in the World-Society. in: Gunther Teubner (Hg.) Global Law Without A State. Dartsmouth: London 1996, 3-28. Italienische Fassung: La Bukowina globale: il pluralismo giuridico nella società mondiale. Sociologic a politiche sociali 2, 1999, 49-80. Portugiesische Fassung: Bukowina global sobre a emergência de um pluralismo jurídico transnacional. Impulso: Direito e Globalização 14, 2003. Georgische Fassung: Globaluri bukovina: samarTlebrivi pluralizmi msoflio sazogadoebaSi. Journal of the Institute of State and Law of the Georgian Academy of Sciences 2005 (im Erscheinen)
Reflexives Recht. Entwicklungsmodelle des Rechts in vergleichender Perspektive (EUI Working Paper 1982/13). Archiv für Rechts- und Sozialphilosophie 68, 1982, 13-59, und in: Werner Maihofer (Hg.), Noi si Mura, Schriftenreihe des Europäischen Hochschulinstituts, Florenz 1986, 290-340. Englische Fassung: Substantive and Reflexive Elements in Modern Law. (EUI Working Paper 1982/14). Law and Society Review 17, 1983, 239-285 und in: Kahei Rokumoto (Hg.) Sociological Theories of Law. Dartmouth, Aldershot 1994, 415-462. Neuabdruck in: Carroll Seron, The Law and Society Canon, Ashgate, Aldershot 2005 (im Erscheinen). Französische Fassung: Eléments 'substantifs' et 'réflexifs' dans le droit moderne. L'Interdit. Revue de Psychanalyse Institutionelle, 1984, 129-132, und Droit et réflexivité: une perspective comparative sur des modèles d'évolution juridique in: Gunther Teubner, Droit et réflexivité. Librairie générale de droit et de jurisprudence, Paris 1994, 3-50. Dänische Fassung: Refleksiv Ret: Udviklingsmodeller i sammenlignende perspektiv. In: Asmund Born, Nils Bredsdorff, Leif Hansen and Finn Hansson (Hg.) Refleksiv Ret. Publication Series of the Institut for Organisation og Arbeidssociologi. Nytfrasamfundsvidenskaberne, Kopenhagen 1988, 21-79.
Assessing enhanced knowledge discovery systems (eKDSs) constitutes an intricate issue that is understood merely to a certain extent by now. Based upon an analysis of why it is difficult to formally evaluate eKDSs, it is argued for a change of perspective: eKDSs should be understood as intelligent tools for qualitative analysis that support, rather than substitute, the user in the exploration of the data; a qualitative gap will be identified as the main reason why the evaluation of enhanced knowledge discovery systems is difficult. In order to deal with this problem, the construction of a best practice model for eKDSs is advocated. Based on a brief recapitulation of similar work on spoken language dialogue systems, first steps towards achieving this goal are performed, and directions of future research are outlined.
Syntactic coindexing restrictions are by now known to be of central importance to practical anaphor resolution approaches. Since, in particular due to structural ambiguity, the assumption of the availability of a unique syntactic reading proves to be unrealistic, robust anaphor resolution relies on techniques to overcome this deficiency.
This paper describes the ROSANA approach, which generalizes the verification of coindexing restrictions in order to make it applicable to the deficient syntactic descriptions that are provided by a robust state-of-the-art parser. By a formal evaluation on two corpora that differ with respect to text genre and domain, it is shown that ROSANA achieves high-quality robust coreference resolution. Moreover, by an in-depth analysis, it is proven that the robust implementation of syntactic disjoint reference is nearly optimal. The study reveals that, compared with approaches that rely on shallow preprocessing, the largely nonheuristic disjoint reference algorithmization opens up the possibility/or a slight improvement. Furthermore, it is shown that more significant gains are to be expected elsewhere, particularly from a text-genre-specific choice of preference strategies.
The performance study of the ROSANA system crucially rests on an enhanced evaluation methodology for coreference resolution systems, the development of which constitutes the second major contribution o/the paper. As a supplement to the model-theoretic scoring scheme that was developed for the Message Understanding Conference (MUC) evaluations, additional evaluation measures are defined that, on one hand, support the developer of anaphor resolution systems, and, on the other hand, shed light on application aspects of pronoun interpretation.
This paper is focused on the coordination of order and production policy between buyers and suppliers in supply chains. When a buyer and a supplier of an item work independently, the buyer will place orders based on his economic order quantity (EOQ). However, the buyer s EOQ may not lead to an optimal policy for the supplier. It can be shown that a cooperative batching policy can reduce total cost significantly. Should the buyer have the more powerful position to enforce his EOQ on the supplier, then no incentive exists for him to deviate from his EOQ in order to choose a cooperative batching policy. To provide an incentive to order in quantities suitable to the supplier, the supplier could offer a side payment. One critical assumption made throughout in the literature dealing with incentive schemes to influence buyer s ordering policy is that the supplier has complete information regarding buyer s cost structure. However, this assumption is far from realistic. As a consequence, the buyer has no incentive to report truthfully on his cost structure. Moreover there is an incentive to overstate the total relevant cost in order to obtain as high a side payment as possible. This paper provides a bargaining model with asymmetric information about the buyer s cost structure assuming that the buyer has the bargaining power to enforce his EOQ on the supplier in case of a break-down in negotiations. An algorithm for the determination of an optimal set of contracts which are specifically designed for different cost structures of the buyer, assumed by the supplier, will be presented. This algorithm was implemented in a software application, that supports the supplier in determining the optimal set of contracts.
Die zunehmende Monopolisierung auf dem Markt für Informationsressourcen im akademischen Sektor führte in den vergangenen Jahren zu einer verstärkten Bildung von Bibliothekskonsortien auf der Abnehmerseite, die einen Gegenpol in Form einer Einkaufsgenossenschaft darstellen sollten [McCa02]. Diese Tendenzen lassen sich in verschiedenen Ländern wie etwa in Deutschland, England, der Schweiz und der Niederlande beobachten [Okerso]. In den USA sind Konsortien eher selten zu finden; das größte Konsortium ist hier OHIO-Link (http://www.lib.ohio-state.edu/). In Deutschland richten sich die meisten Konsortien wegen der föderalen Finanzierungsstrukturen regional aus; überregionale bzw. deutschlandweite Konsortien sind derzeit noch selten. Ein Zusammenschluss auf thematischer Grundlage findet derzeit so gut wie gar nicht statt, vielmehr werden möglichst viele Bibliotheken in Konsortien unabhängig von den an den jeweiligen Standorten betriebenen Forschungsschwerpunkten eingebunden [AnDe02]....
A memory checker for a data structure provides a method to check that the output of the data structure operations is consistent with the input even if the data is stored on some insecure medium. In [8] we present a general solution for all data structures that are based on insert(i,v) and delete(j) commands. In particular this includes stacks, queues, deques (double-ended queues) and lists. Here, we describe more time and space efficient solutions for stacks, queues and deques. Each algorithm takes only a single function evaluation of a pseudorandomlike function like DES or a collision-free hash function like MD5 or SHA for each push/pop resp. enqueue/dequeue command making our methods applicable to smart cards.
We analyse a continued fraction algorithm (abbreviated CFA) for arbitrary dimension n showing that it produces simultaneous diophantine approximations which are up to the factor 2^((n+2)/4) best possible. Given a real vector x=(x_1,...,x_{n-1},1) in R^n this CFA generates a sequence of vectors (p_1^(k),...,p_{n-1}^(k),q^(k)) in Z^n, k=1,2,... with increasing integers |q^{(k)}| satisfying for i=1,...,n-1 | x_i - p_i^(k)/q^(k) | <= 2^((n+2)/4) sqrt(1+x_i^2) |q^(k)|^(1+1/(n-1)) By a theorem of Dirichlet this bound is best possible in that the exponent 1+1/(n-1) can in general not be increased.
Parallel FFT-hashing
(1994)
We propose two families of scalable hash functions for collision resistant hashing that are highly parallel and based on the generalized fast Fourier transform (FFT). FFT hashing is based on multipermutations. This is a basic cryptographic primitive for perfect generation of diffusion and confusion which generalizes the boxes of the classic FFT. The slower FFT hash functions iterate a compression function. For the faster FFT hash functions all rounds are alike with the same number of message words entering each round.
Let b1, . . . , bm 2 IRn be an arbitrary basis of lattice L that is a block Korkin Zolotarev basis with block size ¯ and let ¸i(L) denote the successive minima of lattice L. We prove that for i = 1, . . . ,m 4 i + 3 ° 2 i 1 ¯ 1 ¯ · kbik2/¸i(L)2 · ° 2m i ¯ 1 ¯ i + 3 4 where °¯ is the Hermite constant. For ¯ = 3 we establish the optimal upper bound kb1k2/¸1(L)2 · µ3 2¶m 1 2 1 and we present block Korkin Zolotarev lattice bases for which this bound is tight. We improve the Nearest Plane Algorithm of Babai (1986) using block Korkin Zolotarev bases. Given a block Korkin Zolotarev basis b1, . . . , bm with block size ¯ and x 2 L(b1, . . . , bm) a lattice point v can be found in time ¯O(¯) satisfying kx vk2 · m° 2m ¯ 1 ¯ minu2L kx uk2.
Let G be a group of prime order q with generator g. We study hardcore subsets H is include in G of the discrete logarithm (DL) log g in the model of generic algorithms. In this model we count group operations such as multiplication, division while computations with non-group data are for free. It is known from Nechaev (1994) and Shoup (1997) that generic DL-algorithms for the entire group G must perform p2q generic steps. We show that DL-algorithms for small subsets H is include in G require m/ 2 + o(m) generic steps for almost all H of size #H = m with m <= sqrt(q). Conversely, m/2 + 1 generic steps are su±cient for all H is include in G of even size m. Our main result justifies to generate secret DL-keys from seeds that are only 1/2 * log2 q bits long.
We show that P(n)*(P(n)) for p = 2 with its geometrically induced structure maps is not an Hopf algebroid because neither the augmentation Epsilon nor the coproduct Delta are multiplicative. As a consequence the algebra structure of P(n)*(P(n)) is slightly different from what was supposed to be the case. We give formulas for Epsilon(xy) and Delta(xy) and show that the inversion of the formal group of P(n) is induced by an antimultiplicative involution Xi : P(n) -> P(n). Some consequences for multiplicative and antimultiplicative automorphisms of K(n) for p = 2 are also discussed.
The general subset sum problem is NP-complete. However, there are two algorithms, one due to Brickell and the other to Lagarias and Odlyzko, which in polynomial time solve almost all subset sum problems of sufficiently low density. Both methods rely on basis reduction algorithms to find short nonzero vectors in special lattices. The Lagarias-Odlyzko algorithm would solve almost all subset sum problems of density < 0.6463 . . . in polynomial time if it could invoke a polynomial-time algorithm for finding the shortest non-zero vector in a lattice. This paper presents two modifications of that algorithm, either one of which would solve almost all problems of density < 0.9408 . . . if it could find shortest non-zero vectors in lattices. These modifications also yield dramatic improvements in practice when they are combined with known lattice basis reduction algorithms.
Public key signature schemes are necessary for the access control to communication networks and for proving the authenticity of sensitive messages such as electronic fund transfers. Since the invention of the RSA scheme by Rivest, Shamir and Adleman (1978) research has focused on improving the e±ciency of these schemes. In this paper we present an efficient algorithm for generating public key signatures which is particularly suited for interactions between smart cards and terminals.
We present a novel parallel one-more signature forgery against blind Okamoto-Schnorr and blind Schnorr signatures in which an attacker interacts some times with a legitimate signer and produces from these interactions signatures. Security against the new attack requires that the following ROS-problem is intractable: find an overdetermined, solvable system of linear equations modulo with random inhomogenities (right sides). There is an inherent weakness in the security result of POINTCHEVAL AND STERN. Theorem 26 [PS00] does not cover attacks with 4 parallel interactions for elliptic curves of order 2200. That would require the intractability of the ROS-problem, a plausible but novel complexity assumption. Conversely, assuming the intractability of the ROS-problem, we show that Schnorr signatures are secure in the random oracle and generic group model against the one-more signature forgery.
The large conductance voltage- and Ca2+-activated potassium (BK) channel has been suggested to play an important role in the signal transduction process of cochlear inner hair cells. BK channels have been shown to be composed of the pore-forming alpha-subunit coexpressed with the auxiliary beta-1-subunit. Analyzing the hearing function and cochlear phenotype of BK channel alpha-(BKalpha–/–) and beta-1-subunit (BKbeta-1–/–) knockout mice, we demonstrate normal hearing function and cochlear structure of BKbeta-1–/– mice. During the first 4 postnatal weeks also, BKalpha–/– mice most surprisingly did not show any obvious hearing deficits. High-frequency hearing loss developed in BKalpha–/– mice only from ca. 8 weeks postnatally onward and was accompanied by a lack of distortion product otoacoustic emissions, suggesting outer hair cell (OHC) dysfunction. Hearing loss was linked to a loss of the KCNQ4 potassium channel in membranes of OHCs in the basal and midbasal cochlear turn, preceding hair cell degeneration and leading to a similar phenotype as elicited by pharmacologic blockade of KCNQ4 channels. Although the actual link between BK gene deletion, loss of KCNQ4 in OHCs, and OHC degeneration requires further investigation, data already suggest human BK-coding slo1 gene mutation as a susceptibility factor for progressive deafness, similar to KCNQ4 potassium channel mutations. © 2004, The National Academy of Sciences. Freely available online through the PNAS open access option.
Background: The existence of a constitutively expressed machinery for death in individual cells has led to the notion that survival factors repress this machinery and, if such factors are unavailable, cells die by default. In many cells, however, mRNA and protein synthesis inhibitors induce apoptosis, suggesting that in some cases transcriptional activity might actually impede cell death. To identify transcriptional mechanisms that interfere with cell death and survival, we combined gene trap mutagenesis with site-specific recombination (Cre/loxP system) to isolate genes from cells undergoing apoptosis by growth factor deprivation.
Results: From an integration library consisting of approximately 2 × 106 unique proviral integrations obtained by infecting the interleukin-3 (IL-3)-dependent hematopoietic cell line - FLOXIL3 - with U3Cre gene trap virus, we have isolated 125 individual clones that converted to factor independence upon IL-3 withdrawal. Of 102 cellular sequences adjacent to U3Cre integration sites, 17% belonged to known genes, 11% matched single expressed sequence tags (ESTs) or full cDNAs with unknown function and 72% had no match within the public databases. Most of the known genes recovered in this analysis encoded proteins with survival functions.
Conclusions: We have shown that hematopoietic cells undergoing apoptosis after withdrawal of IL-3 activate survival genes that impede cell death. This results in reduced apoptosis and improved survival of cells treated with a transient apoptotic stimulus. Thus, apoptosis in hematopoietic cells is the end result of a conflict between death and survival signals, rather than a simple death by default.
An excess of the proinflammatory substance IL-18 is present in joints of patients with rheumatoid arthritis (RA), and expression of IL-18 receptor (IL-18R) regulates IL-18 bioactivity in various cell types. We examined the expression of IL-18R alpha-chain and beta-chain and the biologic effects of IL-18 in fibroblast-like synoviocytes (FLS) after long-term culture. The presence of both IL-18R chains was a prerequisite for IL-18 signal transduction in FLS. However, all FLS cultures studied were either resistant or barely responsive to IL-18 stimulation as regards cell proliferation, expression of adhesion molecules ICAM-1 and vascular cell adhesion molecule (VCAM)-1, and the release of interstitial collagenase and stromelysin, IL-6 and IL-8, prostaglandin E2, or nitric oxide. We conclude that the presence of macrophages or IL-18R+ T cells that can respond directly to IL-18 is essential for the proinflammatory effects of IL-18 in synovitis in RA. Open Access: Published: 14 November 2001 © 2002 Möller et al., licensee BioMed Central Ltd (Print ISSN 1465-9905; Online ISSN 1465-9913)
Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is performed mainly in patients with high-risk or advanced hematologic malignancies and congenital or acquired aplastic anemias. In the context of the significant risk of graft failure after allo-HSCT from alternative donors and the risk of relapse in recipients transplanted for malignancy, the precise monitoring of posttransplant hematopoietic chimerism is of utmost interest. Useful molecular methods for chimerism quantification after allogeneic transplantation, aimed at distinguishing precisely between donor's and recipient's cells, are PCR-based analyses of polymorphic DNA markers. Such analyses can be performed regardless of donor's and recipient's sex. Additionally, in patients after sex-mismatched allo-HSCT, fluorescent in situ hybridization (FISH) can be applied. Methods: We compared different techniques for analysis of posttransplant chimerism, namely FISH and PCR-based molecular methods with automated detection of fluorescent products in an ALFExpress DNA Sequencer (Pharmacia) or ABI 310 Genetic Analyzer (PE). We used Spearman correlation test. Results: We have found high correlation between results obtained from the PCR/ALF Express and PCR/ABI 310 Genetic Analyzer. Lower, but still positive correlations were found between results of FISH technique and results obtained using automated DNA sizing technology. Conclusions: All the methods applied enable a rapid and accurate detection of post-HSCT chimerism.
Background: To investigate the occupational risk of tuberculosis (TB) infection in a low-incidence setting, data from a prospective study of patients with culture-confirmed TB conducted in Hamburg, Germany, from 1997 to 2002 were evaluated. Methods: M. tuberculosis isolates were genotyped by IS6110 RFLP analysis. Results of contact tracing and additional patient interviews were used for further epidemiological analyses. Results: Out of 848 cases included in the cluster analysis, 286 (33.7%) were classified into 76 clusters comprising 2 to 39 patients. In total, two patients in the non-cluster and eight patients in the cluster group were health-care workers. Logistic regression analysis confirmed work in the health-care sector as the strongest predictor for clustering (OR 17.9). However, only two of the eight transmission links among the eight clusters involving health-care workers had been detected previously. Overall, conventional contact tracing performed before genotyping had identified only 26 (25.2%) of the 103 contact persons with the disease among the clustered cases whose transmission links were epidemiologically verified. Conclusion: Recent transmission was found to be strongly associated with health-care work in a setting with low incidence of TB. Conventional contact tracing alone was shown to be insufficient to discover recent transmission chains. The data presented also indicate the need for establishing improved TB control strategies in health-care settings.
Introduction: ScFv(FRP5)-ETA is a recombinant antibody toxin with binding specificity for ErbB2 (HER2). It consists of an N-terminal single-chain antibody fragment (scFv), genetically linked to truncated Pseudomonas exotoxin A (ETA). Potent antitumoral activity of scFv(FRP5)-ETA against ErbB2-overexpressing tumor cells was previously demonstrated in vitro and in animal models. Here we report the first systemic application of scFv(FRP5)-ETA in human cancer patients.
Methods: We have performed a phase I dose-finding study, with the objective to assess the maximum tolerated dose and the dose-limiting toxicity of intravenously injected scFv(FRP5)-ETA. Eighteen patients suffering from ErbB2-expressing metastatic breast cancers, prostate cancers, head and neck cancer, non small cell lung cancer, or transitional cell carcinoma were treated. Dose levels of 2, 4, 10, 12.5, and 20 μg/kg scFv(FRP5)-ETA were administered as five daily infusions each for two consecutive weeks.
Results: No hematologic, renal, and/or cardiovascular toxicities were noted in any of the patients treated. However, transient elevation of liver enzymes was observed, and considered dose limiting, in one of six patients at the maximum tolerated dose of 12.5 μg/kg, and in two of three patients at 20 μg/kg. Fifteen minutes after injection, peak concentrations of more than 100 ng/ml scFv(FRP5)-ETA were obtained at a dose of 10 μg/kg, indicating that predicted therapeutic levels of the recombinant protein can be applied without inducing toxic side effects. Induction of antibodies against scFv(FRP5)-ETA was observed 8 days after initiation of therapy in 13 patients investigated, but only in five of these patients could neutralizing activity be detected. Two patients showed stable disease and in three patients clinical signs of activity in terms of signs and symptoms were observed (all treated at doses ≥ 10 μg/kg). Disease progression occurred in 11 of the patients.
Conclusion: Our results demonstrate that systemic therapy with scFv(FRP5)-ETA can be safely administered up to a maximum tolerated dose of 12.5 μg/kg in patients with ErbB2-expressing tumors, justifying further clinical development.
Background: The cosmopolitan moon jelly Aurelia is characterized by high degrees of morphological and ecological plasticity, and subsequently by an unclear taxonomic status. The latter has been revised repeatedly over the last century, dividing the genus Aurelia in as many as 12 or as little as two species. We used molecular data and phenotypic traits to unravel speciation processes and phylogeographic patterns in Aurelia.
Results: Mitochondrial and nuclear DNA data (16S and ITS-1/5.8S rDNA) from 66 world-wide sampled specimens reveal star-like tree topologies, unambiguously differentiating 7 (mtDNA) and 8 (ncDNA) genetic entities with sequence divergences ranging from 7.8 to 14% (mtDNA) and 5 to 32% (ncDNA), respectively. Phylogenetic patterns strongly suggest historic speciation events and the reconstruction of at least 7 different species within Aurelia. Both genetic divergences and life history traits showed associations to environmental factors, suggesting ecological differentiation forced by divergent selection. Hybridization and introgression between Aurelia lineages likely occurred due to secondary contacts, which, however, did not disrupt the unambiguousness of genetic separation.
Conclusions: Our findings recommend Aurelia as a model system for using the combined power of organismic, ecological, and molecular data to unravel speciation processes in cosmopolitan marine organisms.
© 2002 Schroth et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any medium for any non-commercial purpose, provided this notice is preserved along with the article's original URL: http://www.biomedcentral.com/1471-2148/2/1
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.
Background: The neurophysiological and neuroanatomical foundations of persistent developmental stuttering (PDS) are still a matter of dispute. A main argument is that stutterers show atypical anatomical asymmetries of speech-relevant brain areas, which possibly affect speech fluency. The major aim of this study was to determine whether adults with PDS have anomalous anatomy in cortical speech-language areas. Methods: Adults with PDS (n = 10) and controls (n = 10) matched for age, sex, hand preference, and education were studied using high-resolution MRI scans. Using a new variant of the voxel-based morphometry technique (augmented VBM) the brains of stutterers and non-stutterers were compared with respect to white matter (WM) and grey matter (GM) differences. Results: We found increased WM volumes in a right-hemispheric network comprising the superior temporal gyrus (including the planum temporale), the inferior frontal gyrus (including the pars triangularis), the precentral gyrus in the vicinity of the face and mouth representation, and the anterior middle frontal gyrus. In addition, we detected a leftward WM asymmetry in the auditory cortex in non-stutterers, while stutterers showed symmetric WM volumes. Conclusions: These results provide strong evidence that adults with PDS have anomalous anatomy not only in perisylvian speech and language areas but also in prefrontal and sensorimotor areas. Whether this atypical asymmetry of WM is the cause or the consequence of stuttering is still an unanswered question. This article is available from: http://www.biomedcentral.com/1471-2377/4/23 © 2004 Jäncke et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
First paragraph (this article has no abstract) Persistent stimulation of nociceptors results in sensitization of nociceptive sensory neurons, which is associated with hyperalgesia and allodynia. The release of NO and subsequent synthesis of cGMP in the spinal cord are involved in this process. cGMP-dependent protein kinase I (PKG-I) has been suggested to act as a downstream target of cGMP, but its exact role in nociception hadn't been characterized yet. To further evaluate the NO/cGMP/PKG-I pathway in nociception we assessed the effects of PKG-I inhibiton and activaton in the rat formalin assay and analyzed the nociceptive behavior of PKG-I-/- mice. Open access article.
Background: In general shell-less slugs are considered to be slimy animals with a rather dull appearance and a pest to garden plants. But marine slugs usually are beautifully coloured animals belonging to the less-known Opisthobranchia. They are characterized by a large array of interesting biological phenomena, usually related to foraging and/or defence. In this paper our knowledge of shell reduction, correlated with the evolution of different defensive and foraging strategies is reviewed, and new results on histology of different glandular systems are included. Results: Based on a phylogeny obtained by morphological and histological data, the parallel reduction of the shell within the different groups is outlined. Major food sources are given and glandular structures are described as possible defensive structures in the external epithelia, and as internal glands. Conclusion: According to phylogenetic analyses, the reduction of the shell correlates with the evolution of defensive strategies. Many different kinds of defence structures, like cleptocnides, mantle dermal formations (MDFs), and acid glands, are only present in shell-less slugs. In several cases, it is not clear whether the defensive devices were a prerequisite for the reduction of the shell, or reduction occurred before. Reduction of the shell and acquisition of different defensive structures had an implication on exploration of new food sources and therefore likely enhanced adaptive radiation of several groups. © 2005 Wägele and Klussmann-Kolb; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited: http://www.frontiersinzoology.com/content/2/1/3/
Background: Tumor development remains one of the major obstacles following organ transplantation. Immunosuppressive drugs such as cyclosporine and tacrolimus directly contribute to enhanced malignancy, whereas the influence of the novel compound mycophenolate mofetil (MMF) on tumor cell dissemination has not been explored. We therefore investigated the adhesion capacity of colon, pancreas, prostate and kidney carcinoma cell lines to endothelium, as well as their beta1 integrin expression profile before and after MMF treatment. Methods: Tumor cell adhesion to endothelial cell monolayers was evaluated in the presence of 0.1 and 1 μM MMF and compared to unstimulated controls. beta1 integrin analysis included alpha1beta1 (CD49a), alpha2beta1 (CD49b), alpha3beta1 (CD49c), alpha4beta1 (CD49d), alpha5beta1 (CD49e), and alpha6beta1 (CD49f) receptors, and was carried out by reverse transcriptase-polymerase chain reaction, confocal microscopy and flow cytometry. Results: Adhesion of the colon carcinoma cell line HT-29 was strongly reduced in the presence of 0.1 μM MMF. This effect was accompanied by down-regulation of alpha3beta1 and alpha6beta1 surface expression and of alpha3beta1 and alpha6beta1 coding mRNA. Adhesion of the prostate tumor cell line DU-145 was blocked dose-dependently by MMF. In contrast to MMF's effects on HT-29 cells, MMF dose-dependently up-regulated alpha1beta1, alpha2beta1, alpha3beta1, and alpha5beta1 on DU-145 tumor cell membranes. Conclusion: We conclude that MMF possesses distinct anti-tumoral properties, particularly in colon and prostate carcinoma cells. Adhesion blockage of HT-29 cells was due to the loss of alpha3beta1 and alpha6beta1 surface expression, which might contribute to a reduced invasive behaviour of this tumor entity. The enhancement of integrin beta1 subtypes observed in DU-145 cells possibly causes re-differentiation towards a low-invasive phenotype.
Background: In rat, deafferentation of one labyrinth (unilateral labyrinthectomy) results in a characteristic syndrome of ocular and motor postural disorders (e.g., barrel rotation, circling behavior, and spontaneous nystagmus). Behavioral recovery (e.g., diminished symptoms), encompassing 1 week after unilateral labyrinthectomy, has been termed vestibular compensation. Evidence suggesting that the histamine H3 receptor plays a key role in vestibular compensation comes from studies indicating that betahistine, a histamine-like drug that acts as both a partial histamine H1 receptor agonist and an H3 receptor antagonist, can accelerate the process of vestibular compensation. Results: Expression levels for histamine H3 receptor (total) as well as three isoforms which display variable lengths of the third intracellular loop of the receptor were analyzed using in situ hybridization on brain sections containing the rat medial vestibular nucleus after unilateral labyrinthectomy. We compared these expression levels to H3 receptor binding densities. Total H3 receptor mRNA levels (detected by oligo probe H3X) as well as mRNA levels of the three receptor isoforms studied (detected by oligo probes H3A, H3B, and H3C) showed a pattern of increase, which was bilaterally significant at 24 h post-lesion for both H3X and H3C, followed by significant bilateral decreases in medial vestibular nuclei occurring 48 h (H3X and H3B) and 1 week post-lesion (H3A, H3B, and H3C). Expression levels of H3B was an exception to the forementioned pattern with significant decreases already detected at 24 h post-lesion. Coinciding with the decreasing trends in H3 receptor mRNA levels was an observed increase in H3 receptor binding densities occurring in the ipsilateral medial vestibular nuclei 48 h post-lesion. Conclusion: Progressive recovery of the resting discharge of the deafferentated medial vestibular nuclei neurons results in functional restoration of the static postural and occulomotor deficits, usually occurring within a time frame of 48 hours in rats. Our data suggests that the H3 receptor may be an essential part of pre-synaptic mechanisms required for reestablishing resting activities 48 h after unilateral labyrinthectomy.
Introduction: This open label, multicentre study was conducted to assess the times to offset of the pharmacodynamic effects and the safety of remifentanil in patients with varying degrees of renal impairment requiring intensive care.
Methods: A total of 40 patients, who were aged 18 years or older and had normal/mildly impaired renal function (estimated creatinine clearance ≥ 50 ml/min; n = 10) or moderate/severe renal impairment (estimated creatinine clearance <50 ml/min; n = 30), were entered into the study. Remifentanil was infused for up to 72 hours (initial rate 6–9 μg/kg per hour), with propofol administered if required, to achieve a target Sedation–Agitation Scale score of 2–4, with no or mild pain.
Results: There was no evidence of increased offset time with increased duration of exposure to remifentanil in either group. The time to offset of the effects of remifentanil (at 8, 24, 48 and 72 hours during scheduled down-titrations of the infusion) were more variable and were statistically significantly longer in the moderate/severe group than in the normal/mild group at 24 hours and 72 hours. These observed differences were not clinically significant (the difference in mean offset at 72 hours was only 16.5 min). Propofol consumption was lower with the remifentanil based technique than with hypnotic based sedative techniques. There were no statistically significant differences between the renal function groups in the incidence of adverse events, and no deaths were attributable to remifentanil use.
Conclusion: Remifentanil was well tolerated, and the offset of pharmacodynamic effects was not prolonged either as a result of renal dysfunction or prolonged infusion up to 72 hours.
The study of organisms with restricted dispersal abilities and presence in the fossil record is particularly adequate to understand the impact of climate changes on the distribution and genetic structure of species. Trochoidea geyeri (Soós 1926) is a land snail restricted to a patchy, insular distribution in Germany and France. Fossil evidence suggests that current populations of T. geyeri are relicts of a much more widespread distribution during more favourable climatic periods in the Pleistocene. Results: Phylogeographic analysis of the mitochondrial 16S rDNA and nuclear ITS-1 sequence variation was used to infer the history of the remnant populations of T. geyeri. Nested clade analysis for both loci suggested that the origin of the species is in the Provence from where it expanded its range first to Southwest France and subsequently from there to Germany. Estimated divergence times predating the last glacial maximum between 25–17 ka implied that the colonization of the northern part of the current species range occurred during the Pleistocene. Conclusion: We conclude that T. geyeri could quite successfully persist in cryptic refugia during major climatic changes in the past, despite of a restricted capacity of individuals to actively avoid unfavourable conditions.
Western cultures have witnessed a tremendous cultural and social transformation of sexuality in the years since the sexual revolution. Apart from a few public debates and scandals, the process has moved along gradually and quietly. Yet its real and symbolic effects are probably much more consequential than those generated by the sexual revolution of the sixties. Sigusch refers to the broad-based recoding and reassessment of the sexual sphere during the eighties and nineties as the "neosexual revolution". The neosexual revolution is dismantling the old patterns of sexuality and reassembling them anew. In the process, dimensions, intimate relationships, preferences and sexual fragments emerge, many of which had submerged, were unnamed or simply did not exist before. In general, sexuality has lost much of its symbolic meaning as a cultural phenomenon. Sexuality is no longer the great metaphor for pleasure and happiness, nor is it so greatly overestimated as it was during the sexual revolution. It is now widely taken for granted, much like egotism or motility. Whereas sex was once mystified in a positive sense - as ecstasy and transgression, it has now taken on a negative mystification characterized by abuse, violence and deadly infection. While the old sexuality was based primarily upon sexual instinct, orgasm and the heterosexual couple, neosexualities revolve predominantly around gender difference, thrills, self-gratification and prosthetic substitution. From the vast number of interrelated processes from which neosexualities emerge, three empirically observable phenomena have been selected for discussion here: the dissociation of the sexual sphere, the dispersion of sexual fragments and the diversification of intimate relationships. The outcome of the neosexual revolution may be described as "lean sexuality" and "self-sex".
Background: Common warts (verrucae vulgares) are human papilloma virus (HPV) infections with a high incidence and prevalence, most often affecting hands and feet, being able to impair quality of life. About 30 different therapeutic regimens described in literature reveal a lack of a single striking strategy. Recent publications showed positive results of photodynamic therapy (PDT) with 5-aminolevulinic acid (5-ALA) in the treatment of HPV-induced skin diseases, especially warts, using visible light (VIS) to stimulate an absorption band of endogenously formed protoporphyrin IX. Additional experiences adding waterfiltered infrared A (wIRA) during 5-ALA-PDT revealed positive effects. Aim of the study: First prospective randomised controlled blind study including PDT and wIRA in the treatment of recalcitrant common hand and foot warts. Comparison of "5-ALA cream (ALA) vs. placebo cream (PLC)" and "irradiation with visible light and wIRA (VIS+wIRA) vs. irradiation with visible light alone (VIS)". Methods: Pre-treatment with keratolysis (salicylic acid) and curettage. PDT treatment: topical application of 5-ALA (Medac) in "unguentum emulsificans aquosum" vs. placebo; irradiation: combination of VIS and a large amount of wIRA (Hydrosun® radiator type 501, 4 mm water cuvette, waterfiltered spectrum 590-1400 nm, contact-free, typically painless) vs. VIS alone. Post-treatment with retinoic acid ointment. One to three therapy cycles every 3 weeks. Main variable of interest: "Percent change of total wart area of each patient over the time" (18 weeks). Global judgement by patient and by physician and subjective rating of feeling/pain (visual analogue scales). 80 patients with therapy-resistant common hand and foot warts were assigned randomly into one of the four therapy groups with comparable numbers of warts at comparable sites in all groups. Results: The individual total wart area decreased during 18 weeks in group 1 (ALA+VIS+wIRA) and in group 2 (PLC+VIS+wIRA) significantly more than in both groups without wIRA (group 3 (ALA+VIS) and 4 (PLC+VIS)): medians and interquartile ranges: -94% (-100%/-84%) vs. -99% (-100%/-71%) vs. -47% (-75%/0%) vs. -73% (-92%/-27%). After 18 weeks the two groups with wIRA differed remarkably from the two groups without wIRA: 42% vs. 7% completely cured patients; 72% vs. 34% vanished warts. Global judgement by patient and by physician and subjective rating of feeling was much better in the two groups with wIRA than in the two groups without wIRA. Conclusions: The above described complete treatment scheme of hand and foot warts (keratolysis, curettage, PDT treatment, irradiation with VIS+wIRA, retinoic acid ointment; three therapy cycles every 3 weeks) proved to be effective. Within this treatment scheme wIRA as non-invasive and painless treatment modality revealed to be an important, effective factor, while photodynamic therapy with 5-ALA in the described form did not contribute recognisably - neither alone (without wIRA) nor in combination with wIRA - to a clinical improvement. For future treatment of warts an even improved scheme is proposed: one treatment cycle (keratolysis, curettage, wIRA, without PDT) once a week for six to nine weeks. © 2004 Fuchs et al; licensee German Medical Science. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL : http://www.egms.de/en/gms/volume2.shtml
Apparent contradiction between negative effects of UV radiation and positive effects of sun exposure
(2005)
We would like to comment on the three contributions in the Journal of the National Cancer Institute, Vol. 97, No. 3, February 2, 2005: Kathleen M. Egan, Jeffrey A. Sosman, William J. Blot: Editorial: Sunlight and Reduced Risk of Cancer: Is the Real Story Vitamin D? (pp. 161-163) ; Marianne Berwick, Bruce K. Armstrong, Leah Ben-Porat, Judith Fine, Anne Kricker, Carey Eberle, Raymond Barnhill: Sun Exposure and Mortality From Melanoma. (pp. 195-199) ; Karin Ekström Smedby, Henrik Hjalgrim, Mads Melbye, Anna Torrång, Klaus Rostgaard, Lars Munksgaard, et al.: Ultraviolet Radiation Exposure and Risk of Malignant Lymphomas. (pp. 199-209).
E-Learning soll im Rahmen der allgemeinmedizinischen Ausbildung von Medizinstudierenden erprobt werden. Ein zielgruppenspezifisches, multimodulares Online-Angebot begleitet Medizinstudenten des 10. Semesters während ihres dezentralen Praktikums in hausärztlichen Praxen. Folgende Lehrziele werden angestrebt: (1) Einführung in das E-Learning, (2) Klinische Allgemeinmedizin - Online-Modul, (3) Chronic Care Online-Modul, (4) Online-Bewerbung. Die systematische Evaluation zeigt, dass E-Learning die Kommunikation der Studierenden untereinander und mit der universitären Lehreinheit während des Praktikum fördert. Auf der Grundlage der in diesem Pilotversuch gewonnenen Erfahrungen erscheint die Kombination mit Präsenzunterricht (Blended Learning) eine vielversprechende Option für die allgemeinmedizinische Ausbildung zu sein.
We reconsider estimates for the heat kernel on weighted graphs recently found by Metzger and Stollmann. In the case that the weights satisfy a positive lower bound as well as a finite upper bound, we obtain a specialized lower estimate and a proper generalization of a previous upper estimate. Reviews: Math. Rev. 1979406, Zbl. Math. 0934.46042
We study the quantum Zeno effect in quantum statistical mechanics within the operator algebraic framework. We formulate a condition for the appearance of the effect in W*-dynamical systems, in terms of the short-time behaviour of the dynamics. Examples of quantum spin systems show that this condition can be effectively applied to quantum statistical mechanical models. Furthermore, we derive an explicit form of the Zeno generator, and use it to construct Gibbs equilibrium states for the Zeno dynamics. As a concrete example, we consider the X-Y model, for which we show that a frequent measurement at a microscopic level, e.g. a single lattice site, can produce a macroscopic effect in changing the global equilibrium. PACS - Klassifikation: 03.65.Xp, 05.30.-d, 02.30. See the corresponding papers: Schmidt, Andreas U.: "Zeno Dynamics of von Neumann Algebras" and "Mathematics of the Quantum Zeno Effect" and the talk "Zeno Dynamics in Quantum Statistical Mechanics" - http://publikationen.ub.uni-frankfurt.de/volltexte/2005/1167/
The dynamical quantum Zeno effect is studied in the context of von Neumann algebras. It is shown that the Zeno dynamics coincides with the modular dynamics of a localized subalgebra. This relates the modular operator of that subalgebra to the modular operator of the original algebra by a variant of the Kato-Lie-Trotter product formula.
We present a method for the construction of a Krein space completion for spaces of test functions, equipped with an indefinite inner product induced by a kernel which is more singular than a distribution of finite order. This generalizes a regularization method for infrared singularities in quantum field theory, introduced by G. Morchio and F. Strocchi, to the case of singularites of infinite order. We give conditions for the possibility of this procedure in terms of local differential operators and the Gelfand-Shilov test function spaces, as well as an abstract sufficient condition. As a model case we construct a maximally positive definite state space for the Heisenberg algebra in the presence of an infinite infrared singularity. See the corresponding paper: Schmidt, Andreas U.: "Mathematical Problems of Gauge Quantum Field Theory: A Survey of the Schwinger Model" and the presentation "Infinite Infrared Regularization in Krein Spaces"
This extended write-up of a talk gives an introductory survey of mathematical problems of the quantization of gauge systems. Using the Schwinger model as an exactly tractable but nontrivial example which exhibits general features of gauge quantum field theory, I cover the following subjects: The axiomatics of quantum field theory, formulation of quantum field theory in terms of Wightman functions, reconstruction of the state space, the local formulation of gauge theories, indefiniteness of the Wightman functions in general and in the special case of the Schwinger model, the state space of the Schwinger model, special features of the model. New results are contained in the Mathematical Appendix, where I consider in an abstract setting the Pontrjagin space structure of a special class of indefinite inner product spaces - the so called quasi-positive ones. This is motivated by the indefinite inner product space structure appearing in the above context and generalizes results of Morchio and Strocchi [J. Math. Phys. 31 (1990) 1467], and Dubin and Tarski [J. Math. Phys. 7 (1966) 574]. See the corresponding paper: Schmidt, Andreas U.: "Infinite Infrared Regularization and a State Space for the Heisenberg Algebra" and the presentation "Infinite Infrared Regularization in Krein Spaces".
Der vorliegende Beitrag - die stark überarbeitete Fassung des Vortrages "Lektüren des Unausdeutbaren ", den der Verfasser im Januar 2004 im Rahmen der kulturwissenschaftlichen Vortragsreihe GrenzBereiche des Lesens hielt - ist auch erschienen in: literatur für leser 27 (2004), Heft 4, S. 181-199. Ein Beispiel für die Schwierigkeit der literarischen Lektüre gibt Friedrich Schmidt. Er untersucht Lektüremöglichkeiten für das formale wie semantische "Abgebrochensein" des literarischen Kunstwerks der Moderne, wie es in den Fragmenten Kafkas seinen exponierten Ausdruck findet. In diesen Texten tritt zur äußeren Unabgeschlossenheit des Textkorpus ein brüchiges Sinngefüge: die Endlosigkeit der Reflexionen und Handlungszüge, die Heterogenität der Erzählfiguren, die Inkonsistenz jeder Bedeutungskonstruktion von Seiten des Lesers. Indem überdies der Abbruch, als verlorene Schrift oder verschwiegene Botschaft, in Kafkas Fragmenten explizit zum Thema wird, erhebt sich der Text gleichzeitig zum metareflexiven Kommentar: er vollzieht selbst, wovon er spricht. Insofern handelt er – sprachskeptisch – vom Defizit seines eigenen Ausdrucks, das letztlich auch von Lektüren nie vollständig eingeholt werden kann.
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.
We investigate hadron production as well as transverse hadron spectra in nucleus-nucleus collisions from 2 A.GeV to 21.3 A.TeV within two independent transport approaches (UrQMD and HSD) that are based on quark, diquark, string and hadronic degrees of freedom. The comparison to experimental data demonstrates that both approaches agree quite well with each other and with the experimental data on hadron production. The enhancement of pion production in central Au+Au (Pb+Pb) collisions relative to scaled pp collisions (the 'kink') is well described by both approaches without involving any phase transition. However, the maximum in the K+/Pi+ ratio at 20 to 30 A.GeV (the 'horn') is missed by ~ 40%. A comparison to the transverse mass spectra from pp and C+C (or Si+Si) reactions shows the reliability of the transport models for light systems. For central Au+Au (Pb+Pb) collisions at bombarding energies above ~ 5 A.GeV, however, the measured K +/- m-theta-spectra have a larger inverse slope parameter than expected from the calculations. The approximately constant slope of K+/-spectra at SPS (the 'step') is not reproduced either. 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 suggests that the additional pressure - as expected from lattice QCD calculations at finite quark chemical potential and temperature - might be generated by strong interactions in the early pre-hadronic/partonic phase of central Au+Au (Pb+Pb) collisions.
We investigate hadron production as well as transverse hadron spectra from proton-proton, proton-nucleus and nucleus-nucleus collisions from 2 A·GeV to 21.3 A·TeV within two independent transport approaches (HSD and UrQMD) that are based on quark, diquark, string and hadronic degrees of freedom. The comparison to experimental data on transverse mass spectra from pp, pA and C+C (or Si+Si) reactions shows the reliability of the transport models for light systems. For central Au+Au (Pb+Pb) collisions at bombarding energies above ~5 A·GeV, furthermore, the measured K± transverse mass spectra have a larger inverse slope parameter than expected from the default calculations. We investigate various scenarios to explore their potential effects on the K± spectra. In particular the initial state Cronin effect is found to play a substantial role at top SPS and RHIC energies. However, the maximum in the K+/..+ ratio at 20 to 30 A·GeV is missed by 40% and the approximately constant slope of the K± spectra at SPS energies is not reproduced either. Our systematic analysis suggests that the additional pressure - as expected from lattice QCD calculations at finite quark chemical potential µq and temperature T- should be generated by strong interactions in the early pre-hadronic/partonic phase of central Au+Au (Pb+Pb) collisions.
In this paper, I investigate more closely the contribution of modal operators to the semantics of comparatives and I show that there is no need for a maximality or minimality operator. Following Kratzer s (1981, 1991) analysis of modal elements, I assume that the meaning of a modal sentence is dependent on a conversational background and an ordering source. For comparative environments, I demonstrate that the ordering source reduces a set of possible degrees to a single degree that is most (or least) wanted or expected, i.e., maximality and minimality readings of comparative constructions are an effect of the pragmatic meaning of the modal.
Friedrich Hassaurek
(1885)
General August Willich
(1878)