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See detailDécision de la Cour de cassation, 1ère Civ., 30 juin 2004
Cuniberti, Gilles UL

in Clunet (2005)

Reconnaissance de mesures conservatoires étrangères.

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See detailPrivate or self-regulation? A comparative study of forest certification choices in Canada, the United States and Germany
Cashore, Benjamin; Van Kooten, G. Cornelis; Vertinsky, Ilan et al

in Forest Policy and Economics (2005), 7(1), 53-69

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See detailPioglitazone reverses down-regulation of cardiac PPARgamma expression in Zucker diabetic fatty rats.
Pelzer, Theo; Jazbutyte, Virginija; Arias-Loza, Paula Anahi et al

in Biochemical and biophysical research communications (2005), 329(2), 726-32

Peroxisome proliferator-activated receptor-gamma (PPARgamma) plays a critical role in peripheral glucose homeostasis and energy metabolism, and inhibits cardiac hypertrophy in non-diabetic animal models ... [more ▼]

Peroxisome proliferator-activated receptor-gamma (PPARgamma) plays a critical role in peripheral glucose homeostasis and energy metabolism, and inhibits cardiac hypertrophy in non-diabetic animal models. The functional role of PPARgamma in the diabetic heart, however, is not fully understood. Therefore, we analyzed cardiac gene expression, metabolic control, and cardiac glucose uptake in male Zucker diabetic fatty rats (ZDF fa/fa) and lean ZDF rats (+/+) treated with the high affinity PPARgamma agonist pioglitazone or placebo from 12 to 24 weeks of age. Hyperglycemia, hyperinsulinemia, and hypertriglyceridemia as well as lower cardiac PPARgamma, glucose transporter-4 and alpha-myosin heavy chain expression levels were detected in diabetic ZDF rats compared to lean animals. Pioglitazone increased body weight and improved metabolic control, cardiac PPARgamma, glut-4, and alpha-MHC expression levels in diabetic ZDF rats. Cardiac [(18)F]fluorodeoxyglucose uptake was not detectable by micro-PET studies in untreated and pioglitazone treated ZDF fa/fa rats but was observed after administration of insulin to pioglitazone treated ZDF fa/fa rats. PPARgamma agonists favorably affect cardiac gene expression in type-2 diabetic rats via activation and up-regulation of cardiac PPARgamma expression whereas improvement of impaired cardiac glucose uptake in advanced type-2 diabetes requires co-administration of insulin. [less ▲]

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See detailShopping hours and price competition
Inderst, Roman; Irmen, Andreas UL

in European Economic Review (2005), 49(5), 1105-1124

This Paper develops an argument explaining why retail prices may rise in response to the deregulation of opening hours. We make this point in a model of imperfect duopolistic competition. In a deregulated ... [more ▼]

This Paper develops an argument explaining why retail prices may rise in response to the deregulation of opening hours. We make this point in a model of imperfect duopolistic competition. In a deregulated market retailers view the choice of opening hours as a means to increase the degree of perceived product differentiation thus relaxing price competition. If the opportunity costs of the time spent on shopping are sufficiently high the equilibrium configuration has asymmetric shopping hours where one retailer stays open for longer than the other does. Both retailers charge higher prices than under regulation, and both are strictly better off.<P>(This abstract was borrowed from another version of this item.) [less ▲]

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See detailExactly solvable model of quantum diffusion
Esposito, Massimiliano UL; Gaspard, P.

in Journal of Statistical Physics (2005), 121(3-4),

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See detailThe sarcolemmal calcium pump inhibits the calcineurin/nuclear factor of activated T-cell pathway via interaction with the calcineurin A catalytic subunit.
Buch, Mamta H.; Pickard, Adam; Rodriguez, Antonio et al

in The Journal of biological chemistry (2005), 280(33), 29479-87

The calcineurin/nuclear factor of activated T-cell (NFAT) pathway represents a crucial transducer of cellular function. There is increasing evidence placing the sarcolemmal calcium pump, or plasma ... [more ▼]

The calcineurin/nuclear factor of activated T-cell (NFAT) pathway represents a crucial transducer of cellular function. There is increasing evidence placing the sarcolemmal calcium pump, or plasma membrane calcium/calmodulin ATPase pump (PMCA), as a potential modulator of signal transduction pathways. We demonstrate a novel interaction between PMCA and the calcium/calmodulin-dependent phosphatase, calcineurin, in mammalian cells. The interaction domains were located to the catalytic domain of PMCA4b and the catalytic domain of the calcineurin A subunit. Endogenous calcineurin activity, assessed by measuring the transcriptional activity of its best characterized substrate, NFAT, was significantly inhibited by 60% in the presence of ectopic PMCA4b. This inhibition was notably reversed by the co-expression of the PMCA4b interaction domain, demonstrating the functional significance of this interaction. PMCA4b was, however, unable to confer its inhibitory effect in the presence of a calcium/calmodulin-independent constitutively active mutant calcineurin A suggesting a calcium/calmodulin-dependent mechanism. The modulatory function of PMCA4b is further supported by the observation that endogenous calcineurin moves from the cytoplasm to the plasma membrane when PMCA4b is overexpressed. We suggest recruitment by PMCA4b of calcineurin to a low calcium environment as a possible explanation for these findings. In summary, our results offer strong evidence for a novel functional interaction between PMCA and calcineurin, suggesting a role for PMCA as a negative modulator of calcineurin-mediated signaling pathways in mammalian cells. This study reinforces the emerging role of PMCA as a molecular organizer and regulator of signaling transduction pathways. [less ▲]

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See detailDécision de la Cour de Justice des Communautés européennes, 1 mars 2005
Cuniberti, Gilles UL; Winkler, Matteo

in Clunet (2005)

Forum non conveniens et convention de Bruxelles.

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See detailEffects of atmospheric pressure loading and seven-parameter transformations on estimates of geocenter motion and station heights from space geodetic observations
Tregoning, P.; van Dam, Tonie UL

in Journal of Geophysical Research (2005), 110

Variations in fluid loads such as the oceans and the atmosphere deform the surface of the Earth. The accuracy of station coordinates, in particular, heights, that can be estimated depends on how well one ... [more ▼]

Variations in fluid loads such as the oceans and the atmosphere deform the surface of the Earth. The accuracy of station coordinates, in particular, heights, that can be estimated depends on how well one can separate these surface deformations from the associated translational motion between the center of mass of the solid Earth and the total Earth (CM). We applied simulated atmospheric pressure loading effects to the coordinates of sites in the CM frame to explore to what level of accuracy both geocenter motion and accurate station coordinates can actually be recovered from geodetic analyses. We found that standard seven-parameter transformations (three rotations, three translations, scale) generally recover about 80% of the geocenter motion; however, the inclusion of a scale factor permits the aliasing of surface loading deformation, introducing scale errors of up to 0.3 ppb and daily height errors as large as 4 mm. This limits the geophysical studies that can be performed accurately using the results of geodetic analyses where the magnitudes of the signals are small (e.g., tectonic movement of tide gauges, uplift rates for interpreting glacial isostatic adjustment). The quality of the geodetic results is extremely sensitive to the number and distribution of sites used to estimate the transformations and becomes worse when regional (rather than global) sets of sites are used. If the scale factor parameter is omitted, then the amount of aliasing of surface loading effects is reduced considerably and more accurate site velocities and geocenter motion estimates are achieved. [less ▲]

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See detailEffect of gravitational consistency and mass conservation on seasonal surface mass loading models
Clarke, Peter J.; Lavallée, David A.; Blewitt, Geoffrey et al

in Geophysical Research Letters (2005), 32(L08306), 1-5

Increasingly, models of surface mass loads are used either to correct geodetic time coordinates by removing seasonal and other ‘‘noise’’, or for comparison with other geodetic parameters. However, models ... [more ▼]

Increasingly, models of surface mass loads are used either to correct geodetic time coordinates by removing seasonal and other ‘‘noise’’, or for comparison with other geodetic parameters. However, models of surface loading obtained by simply combining the mass redistribution due to individual phenomena will not in general be self- consistent, in that (i) the implied global water budget will not be mass-conserving, and (ii) the modelled sea level will not be an equipotential surface of Earth’s total gravity field. We force closure of the global water budget by allowing the ‘‘passive’’ ocean to change in mass. This medium-term passive ocean response will not be a uniform change in non- steric ocean surface height, but must necessarily be spatially variable to keep the ‘‘passive’’ ocean surface on an equipotential. Using existing load models, we demonstrate the effects of our consistency theory. Geocenter motion is amplified significantly, by up to 43%. [less ▲]

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See detailCandidate metabolic network states in human mitochondria. Impact of diabetes, ischemia, and diet.
Thiele, Ines UL; Price, Nathan D.; Vo, Thuy D. et al

in Journal of Biological Chemistry (2005), 280(12), 11683-95

The human mitochondrial metabolic network was recently reconstructed based on proteomic and biochemical data. Linear programming and uniform random sampling were applied herein to identify candidate ... [more ▼]

The human mitochondrial metabolic network was recently reconstructed based on proteomic and biochemical data. Linear programming and uniform random sampling were applied herein to identify candidate steady states of the metabolic network that were consistent with the imposed physico-chemical constraints and available experimental data. The activity of the mitochondrion was studied under four metabolic conditions: normal physiologic, diabetic, ischemic, and dietetic. Pairwise correlations between steady-state reaction fluxes were calculated in each condition to evaluate the dependence among the reactions in the network. Applying constraints on exchange fluxes resulted in predictions for intracellular fluxes that agreed with experimental data. Analyses of the steady-state flux distributions showed that the experimentally observed reduced activity of pyruvate dehydrogenase in vivo could be a result of stoichiometric constraints and therefore would not necessarily require enzymatic inhibition. The observed changes in the energy metabolism of the mitochondrion under diabetic conditions were used to evaluate the impact of previously suggested treatments. The results showed that neither normalized glucose uptake nor decreased ketone body uptake have a positive effect on the mitochondrial energy metabolism or network flexibility. Taken together, this study showed that sampling of the steady-state flux space is a powerful method to investigate network properties under different conditions and provides a basis for in silico evaluations of effects of potential disease treatments. [less ▲]

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See detailZwischen/Räume und Grenzgänge. Einige Überlegungen zu Bildungsprozessen im Medium des Theaterspielens
Karl, Ute UL

in Korrespondenzen. Zeitschrift für Theaterpädagogik (2005), 21(47), 33-41

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See detailDecoherence and kinetic processes in quantum nanosystems
Esposito, Massimiliano UL; Gaspard, P.

in Physics Letters A (2005), 341(5-6),

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See detailAtmospheric loading corrections applied to GPS data at the observation level
Tregoning, T.; van Dam, Tonie UL

in Geophysical Research Letters (2005), 32(L22310), 1-4

Space-geodetic techniques can detect elastic deformation of the Earth caused by atmospheric pressure loading (ATML). However, it has not yet been demonstrated whether these surface displacements should be ... [more ▼]

Space-geodetic techniques can detect elastic deformation of the Earth caused by atmospheric pressure loading (ATML). However, it has not yet been demonstrated whether these surface displacements should be accounted for at the time of reduction of the observations or by applying time-averaged values to the coordinates after the analysis of the observations. An analysis of the power spectral density of the ATML predicted vertical deformation shows that, aside from the diurnal and semi-diurnal periods, there is very little power in the sub-daily frequencies. The present tidal ATML models improve the analysis at sites near the equator but seem to degrade the height estimates elsewhere. The majority of the non-tidal deformation can be modelled by applying a daily-averaged correction to daily estimates of coordinates but a greater improvement in height RMS is found if non-tidal ATML is applied at the observation level. [less ▲]

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See detailStudies in Philosophy and Education Volume 24
Biesta, Gert UL

in Studies in Philosophy & Education (2005), 24

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See detailAgricultural Sector and Industrial Agglomeration
Zeng, Dao-Zhi; Picard, Pierre M UL

in Journal of Development Economics (2005), 77(1), 75-106

In many developing countries, agriculture hires at least as many workers as manufacturing industries. We investigate an economic geography model in which agricultural goods are costly to transport and in ... [more ▼]

In many developing countries, agriculture hires at least as many workers as manufacturing industries. We investigate an economic geography model in which agricultural goods are costly to transport and in which manufactures hire labor from the local agricultural sector as unskilled labor. Our conclusions show that the parameters in the agricultural sector are crucial to determine the spatial configuration of economic activity. We provide an analytic treatment to the model. The location equilibria are compared with the first and second best outcomes. [less ▲]

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See detailReduced Complexity Equalization schemes for Zero Padded OFDM Systems
Shankar, Bhavani UL; Hari, K. V. S.

in IEEE Signal Processing Letters (2004), 11(9), 752-755

Three reduced complexity equalization schemes for Zero-padded OFDM systems are described. These schemes guarantee Zero-Forcing (ZF) equalization irrespective of the channel s. Two of these schemes ... [more ▼]

Three reduced complexity equalization schemes for Zero-padded OFDM systems are described. These schemes guarantee Zero-Forcing (ZF) equalization irrespective of the channel s. Two of these schemes implement the minimum-norm ZF equalizer efficiently using QR decomposition. In the third scheme, the channel zeros are grouped as being inside or outside or on the unit circle. These groups are then equalized sequentially in a manner so as to tackle excess noise amplification. The three schemes are compared for their computational complexity and Bit Error Rate (BER) performance. It is shown that the attractive scheme depends on the system specifications. The BERComputations trade off occurring in the choice of the right algorithm is also highlighted. [less ▲]

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See detailA spectrophotometric assay of D-glucuronate based on Escherichia coli uronate isomerase and mannonate dehydrogenase
Linster, Carole UL; Van Schaftingen, Emile

in Protein Expression and Purification (2004), 37(2), 352-60

Escherichia coli uronate isomerase and mannonate dehydrogenase were overexpressed in E. coli BL21(DE3)pLysS cells and purified to near-homogeneity. The kinetic properties of the two enzymes were ... [more ▼]

Escherichia coli uronate isomerase and mannonate dehydrogenase were overexpressed in E. coli BL21(DE3)pLysS cells and purified to near-homogeneity. The kinetic properties of the two enzymes were investigated. The isomerase was found to be inhibited by EDTA and to be stimulated by Zn(2+), Co(2+), and Mn(2+), but not by Mg(2+) or Ca(2+). Both enzymes were used to develop a sensitive spectrophotometric assay, in which D-glucuronate is converted to D-mannonate with concomitant oxidation of NADH to NAD(+). The sensitivity of this assay permits the detection of less than 1 nmol D-glucuronate. This assay can also be used to determine the concentration of beta-glucuronides and glucuronate 1-phosphate after enzymatic hydrolysis of these compounds with beta-glucuronidase or alkaline phosphatase. [less ▲]

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See detailPreference aggregation with multiple criteria of ordinal significance
Bisdorff, Raymond UL

in Annales du LAMSADE (2004), 3

In this paper we address the problem of aggregating outranking situations in the presence of multiple preference criteria of ordinal significance. The concept of ordinal concordance of the global ... [more ▼]

In this paper we address the problem of aggregating outranking situations in the presence of multiple preference criteria of ordinal significance. The concept of ordinal concordance of the global outranking relation is defined and an operational test for its presence is developed. Finally, we propose a new kind of robustness analysis for global outranking relations taking into account classical dominance, ordinal and classical majority oncordance in a same bipolar-valued logical framework [less ▲]

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See detailEin Rechenmodell zur Berücksichtigung von verformbaren, teiltragfähigen Anschlüssen bei der Berechnung von Stahlverbundträgern
Jost, Markus; Odenbreit, Christoph UL

in Stahlbau (2004), 73(7), 495--504

Typische Verbundanschlüsse, wie z. B. in Bild 1 dargestellt, haben oft nicht die volle Tragfähigkeit des angeschlossenen Verbundträgers und sind auch zu biegeweich, um das volle Stützmoment, das sich aus ... [more ▼]

Typische Verbundanschlüsse, wie z. B. in Bild 1 dargestellt, haben oft nicht die volle Tragfähigkeit des angeschlossenen Verbundträgers und sind auch zu biegeweich, um das volle Stützmoment, das sich aus der elastischen Berechnung unter der Annahme einer vollen Einspannung ergibt, aufbauen zu können. Andererseits sind aber die Steifigkeiten und die Tragfähigkeiten in den Anschlüssen zu groß, um sie einfach zu vernachlässigen. Im folgenden Artikel wird eine Methode vorgestellt, um die rechnerischen Kennwerte... [less ▲]

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See detailInternational entrepreneurship and the small business
Fletcher, Denise Elaine UL

in Entrepreneurship and Regional Development (2004), 16

The topic of ‘international entrepreneurship’ is becoming increasingly popular with researchers concerned with examining how international and entrepreneurial activities intersect when people in ... [more ▼]

The topic of ‘international entrepreneurship’ is becoming increasingly popular with researchers concerned with examining how international and entrepreneurial activities intersect when people in organizations engage in pro-active brokering and risk-taking behaviour in cross-border contexts. Some caution is needed in over-generalizing the meaning and significance of international entrepreneurship – especially in relation to small businesses. Not all entrepreneurial risk-taking, brokering and opportunity-seeking activities lead to internationalization (as the statistics on small business international activities indicate). This might suggest then that the only truly internationally entrepreneurial firms are those that are ‘born global’. However, their entrepreneurial activities are more ‘spatial’, concerned with what can be constructed again in relation to global markets rather than in relation to the local/regional context in which the business is located. For small firms that internationalize a few years after start-up (late starters), processes of international entrepreneurship are different. For ‘later starters’, international entrepreneurship is distinctive in that it is characterized by extending and modifying entrepreneurial understandings and practices that have been socially constructed in relation to the local and regional context in which the small firm is located. [less ▲]

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See detailTolerant or intolerant character of interacting criteria in aggregation by the Choquet integral
Marichal, Jean-Luc UL

in European Journal of Operational Research (2004), 155(3), 771-791

In many multi-criteria decision-making problems the decision criteria present some interaction whose nature may vary from one situation to another. For example, some criteria may be statistically ... [more ▼]

In many multi-criteria decision-making problems the decision criteria present some interaction whose nature may vary from one situation to another. For example, some criteria may be statistically correlated, thus making them somewhat redundant or opposed. Some others may be somewhat substitutive or complementary depending on the behavior of the decision maker. Some others may be decisive in the sense that the global score (of any alternative) obtained by aggregation is bounded by the partial score along one of them. In this paper we analyze this latter form of interaction. When a criterion bounds the global score from above, it is called a blocker or a veto, due to its rather intolerant character. When it bounds the global score from below, it is then called a pusher or a favor. We thus investigate the tolerance of criteria, or equivalently, the tolerance of the weighted aggregation operator (here the Choquet integral) that is used to aggregate criteria. More specifically, we propose (axiomatically) indices to appraise the extent to which each criterion behaves like a veto or a favor in the aggregation by the Choquet integral. Previous to this, we also propose global tolerance degrees measuring the extent to which the Choquet integral is conjunctive or disjunctive. [less ▲]

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See detailAggregation on finite ordinal scales by scale independent functions
Marichal, Jean-Luc UL; Mesiar, Radko

in Order: A Journal on the Theory of Ordered Sets and its Applications (2004), 21(2), 155-180

We define and investigate the scale independent aggregation functions that are meaningful to aggregate finite ordinal numerical scales. Here scale independence means that the functions always have ... [more ▼]

We define and investigate the scale independent aggregation functions that are meaningful to aggregate finite ordinal numerical scales. Here scale independence means that the functions always have discrete representatives when the ordinal scales are considered as totally ordered finite sets. We also show that those scale independent functions identify with the so-called order invariant functions, which have been described recently. In particular, this identification allows us to justify the continuity property for certain order invariant functions in a natural way. [less ▲]

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See detailIndexikalität und sprachliche Selbstreferenz bei Hegel
Heidemann, Dietmar UL

in Hegel-Studien (2004), 39/40

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See detailSuperconducting gravimeters in seismology
Francis, Olivier UL; van Dam, Tonie UL

in Newsletter of the European-Mediterranean Seismological Centre (2004), 21

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See detailSelbstgesteuertes Bewegungslernen und Lernstrategien
Bund, Andreas UL

in Sportwissenschaft (2004), 34(3), 295-310

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See detailSelf-controlled learning of a complex motor skill: Effects of the learner's preferences on performance and self-efficacy.
Bund, Andreas UL; Wiemeyer, Josef

in Journal of Human Movement Studies (2004), 47

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See detailAssessment of the safety of foods derived from genetically modified crops
König, Ariane UL; Cockburn, A.; Crevel, R. et al

in Food and Chemical Toxicology (2004), 42

This paper provides guidance on how to assess the safety of foods derived from genetically modified crops (GM crops); it summarises conclusions and recommendations of Working Group 1 of the ENTRANSFOOD ... [more ▼]

This paper provides guidance on how to assess the safety of foods derived from genetically modified crops (GM crops); it summarises conclusions and recommendations of Working Group 1 of the ENTRANSFOOD project. The paper provides an approach for adapting the test strategy to the characteristics of the modified crop and the introduced trait, and assessing potential unintended effects from the genetic modification. The proposed approach to safetyassessment starts with the comparison of the new GM crop with a traditional counterpart that is generally accepted as safe based on a history of human food use (the concept of substantial equivalence). This case-focused approach ensures that foods derived from GM crops that have passed this extensive test-regime are as safe and nutritious as currently consumed plant-derived foods. The approach is suitable for current and future GM crops with more complex modifications. First, the paper reviews test methods developed for the risk assessment of chemicals, including food additives and pesticides, discussing which of these methods are suitable for the assessment of recombinant proteins and whole foods. Second, the paper presents a systematic approach to combine test methods for the safetyassessment of foods derived from a specific GM crop. Third, the paper provides an overview on developments in this area that may prove of use in the safetyassessment of GM crops, and recommendations for research priorities. It is concluded that the combination of existing test methods provides a sound test-regime to assess the safety of GM crops. Advances in our understanding of molecular biology, biochemistry, and nutrition may in future allow further improvement of test methods that will over time render the safetyassessment of foods even more effective and informative. [less ▲]

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See detailPopästhetische Verfahren in Theatertexten von René Pollesch und Martin Heckmanns
Bloch, Natalie UL

in Der Deutschunterricht: Beiträge zu seiner Praxis und wissenschaftlichen Grundlegung (2004)

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See detailUne courte introduction à la cryptographie à courbes elliptiques
Bernard, Nicolas UL

in Sciences ENS (2004), (1),

Si tous les cryptologues amateurs connaissent les algorithmes de cryptographie à clef publique ``traditionnels'' tels que RSA, rares sont ceux qui connaissent plus que de nom la cryptographie à clef ... [more ▼]

Si tous les cryptologues amateurs connaissent les algorithmes de cryptographie à clef publique ``traditionnels'' tels que RSA, rares sont ceux qui connaissent plus que de nom la cryptographie à clef publique basée sur les courbes elliptiques. Le but de cet article est donc de présenter ce domaine de manière simple de façon à rester accessible au plus grand nombre. [less ▲]

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See detailMaintaining your immune system--one method for enhanced longevity.
Wollscheid-Lengeling, Evi; Muller, Rolf-Joachim; Balling, Rudi UL et al

in Science of Aging Knowledge Environment [=SAGE KE] (2004), 2004(1), 2

The immune system is an important evolutionary invention to battle invaders in young and old organisms. Successful aging in humans who achieve nonagenarian status and beyond depends on how the immune ... [more ▼]

The immune system is an important evolutionary invention to battle invaders in young and old organisms. Successful aging in humans who achieve nonagenarian status and beyond depends on how the immune system changes over time. Whether certain immune parameters vary with increased age is influenced by the genotype and lifestyle of the individual. [less ▲]

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See detailHoeffding-ANOVA decompositions for symmetric statistics of exchangeable observations
Peccati, Giovanni UL

in Annals of Probability (2004), 32(3A), 1796--1829

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See detail‘School’s just a catalyst.’ Learning, identity and knowledge and the Post-16 curriculum.
Lawy, R. S.; Bloomer, J. M.; Biesta, Gert UL

in Journal of Vocational Education and Training (2004), 56(2), 205-226

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See detailThe Transport Geography of Logistics and Freight Distribution.
Hesse, Markus UL; Rodrigue, Jean-Paul

in Journal of Transport Geography (2004), 12(2), 171-184

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See detailEquivariant operators between some modules of the Lie algebra of vector fields
Poncin, Norbert UL

in Communications in Algebra (2004), 32(7), 2559--2572

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See detailAnticipatory effects of food exposure in women diagnosed with bulimia nervosa.
Legenbauer, Tanja; Vögele, Claus UL; Rüddel, Heinz

in Appetite (2004), (42), 33-40

Objective. To investigate cephalic phase responses (CPRs) in women diagnosed with bulimia nervosa and to test the assumption that eating disordered individuals respond with more marked CPRs and higher ... [more ▼]

Objective. To investigate cephalic phase responses (CPRs) in women diagnosed with bulimia nervosa and to test the assumption that eating disordered individuals respond with more marked CPRs and higher increases in psychophysiological arousal to the presentation of food cues. Method. Thirteen female inpatients diagnosed with bulimia nervosa were compared to 15 non-eating disordered female volunteers. Participants were exposed to their preferred binge food in a single laboratory session with the possibility to eat immediately after the exposure trial. Results. The results show greater salivation responses to food exposure and lower sympathetic arousal in patients diagnosed with bulimia nervosa than in non-eating-disordered participants. Distress and feelings of tension and insecurity during food exposure were higher in patients compared to controls. Discussion. These results support the hypothesis that anticipatory cephalic phase responses are more marked in eating disordered individuals and may therefore play a role in the maintenance of binge eating behavior. [less ▲]

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See detailThe role of the inhibitors of interleukin-6 signal transduction SHP2 and SOCS3 for desensitization of interleukin-6 signalling
Fischer, P.; Lehmann, U.; Sobota, R. M. et al

in Biochemical Journal (2004), 378(Pt 2), 449-60

The immediate early response of cells treated with IL-6 (interleukin-6) is the activation of the signal transducer and activator of transcription (STAT)3. The Src homology domain 2 (SH2)-containing ... [more ▼]

The immediate early response of cells treated with IL-6 (interleukin-6) is the activation of the signal transducer and activator of transcription (STAT)3. The Src homology domain 2 (SH2)-containing protein tyrosine phosphatase SHP2 and the feedback inhibitor SOCS3 (suppressor of cytokine signalling) are potent inhibitors of IL-6 signal transduction. Impaired function of SOCS3 or SHP2 leads to enhanced and prolonged IL-6 signalling. The inhibitory function of both proteins depends on their recruitment to the tyrosine motif 759 within glycoprotein gp130. In contrast to inactivation, desensitization of signal transduction is regarded as impaired responsiveness due to prestimulation. Usually, after activation the sensing receptor becomes inactivated by modifications such as phosphorylation, internalization or degradation. We designed an experimental approach which allows discrimination between desensitization and inactivation of IL-6 signal transduction. We observed that pre-stimulation with IL-6 renders cells less sensitive to further stimulation with IL-6. After several hours, the cells become sensitive again. We show that not only signal transduction through previously activated receptors is affected by desensitization but signalling through receptors which were not targeted by the first stimulation was also attenuated ( trans -desensitization). Interestingly, in contrast to inhibition, desensitization does not depend on the presence of functional SHP2. Furthermore, cells lacking SOCS3 show constitutive STAT3 activation which is not affected by pre-stimulation with IL-6. All these observations suggest that desensitization and inhibition of signalling are mechanistically distinct. [less ▲]

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See detailDie Hauptversammlungslegitimation durch "Hinterlegung" bei girosammelverwahrten Inhaberaktien
Zetzsche, Dirk Andreas UL; Noack, U.

in WM - Wertpapiermitteilungen (2004), (1-9),

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See detailPolarity-directed analog electrooptic switching in a low-polarization chiral smectic liquid crystal with positive dielectric anisotropy
Lagerwall, Jan UL; Kane, Alexander; Clark, Noel A. et al

in Physical Review. E ,Statistical, Nonlinear, and Soft Matter Physics (2004), 70(3), 031703

We describe an analog electro-optic (EO) switching mechanism occurring in thin cells filled with a low- polarization ferroelectric liquid crystal mixture with positive dielectric anisotropy. The mixture ... [more ▼]

We describe an analog electro-optic (EO) switching mechanism occurring in thin cells filled with a low- polarization ferroelectric liquid crystal mixture with positive dielectric anisotropy. The mixture is composed of an achiral nonpolar smectic-C 􏰐Sm-C􏰋 host doped with a small amount of a commercially available unichiral compound. The switching mechanism provides analog EO behavior, and thus could be attractive for informa- tion display applications. The process is polarization-driven for weak fields, while for higher field strength the dielectric coupling dominates the process. [less ▲]

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See detailCommon Polymorphisms in the Glucocorticoid Receptor Gene Are Associated with Adrenocortical Responses to Psychosocial Stress
Wüst, S.; Van Rossum, E. F. C.; Federenko, I. S. et al

in Journal of Clinical Endocrinology and Metabolism (2004), 89(2), 565-573

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See detailCatalytic converters in a one-dimensional cycle simulation code considering three-dimensional behavior.
Peters, Bernhard UL; Wurzenberger, J.

in SAE International Journal of Fuels and Lubricants (2004)

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See detailAntiapoptotic effects of budipine.
Muller, T.; Przuntek, H.; Krüger, Rejko UL et al

in Journal of Neural Transmission (2004), 111(10-11), 1365-73

Apoptosis is one essential step for neuronal death in the nigrostriatal region in patients with Parkinson's disease. Cytotoxic tumor necrosis factor-alpha (TNF-alpha) and the proinflammatory cytokine ... [more ▼]

Apoptosis is one essential step for neuronal death in the nigrostriatal region in patients with Parkinson's disease. Cytotoxic tumor necrosis factor-alpha (TNF-alpha) and the proinflammatory cytokine interleukin-6 (Il-6) provide a proapoptotic environment. We investigated the influence of the antiparkinsonian compound budipine on the release of TNF-alpha and Il-6 in peripheral blood mononuclear cells (PBMC) and on the degree of cisplatin induced apoptotic cell death in SH-SY 5Y human neuroblastoma cells. 10(-7), 10(-8), 10(-9) mol/l of budipine significantly reduced release of TNF-alpha and Il-6 in PBMC and decreased apoptotic cell death after 50 hours and 74 hours in the SH-SY 5Y cells. Our results suggest, that budipine administration provides an antiapoptotic environment and slows neuronal apoptotic and inflammatory mediated loss of neurons. [less ▲]

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See detailSTAT3 is enriched in nuclear bodies.
Herrmann, Andreas; Sommer, Ulrike; Pranada, Albert L. et al

in Journal of Cell Science (2004), 117(Pt 2), 339-49

Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that is involved in a variety of biological functions. It is essential for the signal transduction of interleukin-6 (IL ... [more ▼]

Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that is involved in a variety of biological functions. It is essential for the signal transduction of interleukin-6 (IL-6) and related cytokines. In response to IL-6 stimulation STAT3 becomes phosphorylated and translocates into the nucleus where it binds to enhancer sequences of target genes. We found that activated STAT3 is enriched in dot-like structures within the nucleus, which we termed STAT3 nuclear bodies. To examine the dynamics of STAT3 nuclear body formation, a fusion protein of STAT3 and yellow fluorescent protein (YFP) was constructed. Studies in living cells have shown that the appearance of STAT3 nuclear bodies is transient, correlating with the timecourse of tyrosine-phosphorylation of STAT3. Furthermore, we show by fluorescence recovery after photobleaching (FRAP) analysis that STAT3 within nuclear bodies consists of a highly mobile and an immobile fraction. Colocalization studies provided evidence that these bodies are accompanied with CREB binding protein (CBP) and acetylated histone H4, which are markers for transcriptionally active chromatin. Moreover, STAT3 nuclear bodies in HepG2 cells are not colocalized with promyelocytic leukemia oncoprotein (PML)-containing bodies; neither is a sumoylation of activated STAT3 detectable. Taken together, our data suggest that STAT3 nuclear bodies are either directly involved in active gene transcription or they serve as reservoirs of activated STAT3. [less ▲]

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See detailEconomic Geography and the Distribution of Profits
Picard, Pierre M UL; Thisse, Jacques François

in Journal of Urban Economics (2004), 56(1), 144-167

In modern economies, the amount of profits distributed to shareholders is far from being negligible. We show that the way they are distributed among agents matters for the space-economy. For example, the ... [more ▼]

In modern economies, the amount of profits distributed to shareholders is far from being negligible. We show that the way they are distributed among agents matters for the space-economy. For example, the existence of mobile rentiers is sufficient to make the symmetric configuration unstable for all transport cost values and to allow for the partial agglomeration of firms. Obviously, to account for profits and for their distribution, the assumption of free entry must be abandoned. So doing, we ignore fixed costs and show that it is the combination of imperfect competition and firms’ indivisibility that matters for the formation of agglomeration in economic geography. [less ▲]

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See detailWeak convergence to Ocone martingales: a remark
Peccati, Giovanni UL

in Electronic Communications in Probability (2004), 9

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See detailDesign of channel estimate dependent space-time block codes
Jöngren, George; Skoglund, Mikael; Ottersten, Björn UL

in IEEE Transactions on Communications (2004), 52(7), 11911203

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See detail'Lebenslanges Lernen' als conditio humana: Ein Plädoyer für einen revidierten Lernbegriff
Tröhler, Daniel UL

in Vierteljahresschrift für wissenschaftliche Pädagogik (2004), 80

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See detailStudies in Philosophy and Education Volume 23
Biesta, Gert UL

in Studies in Philosophy & Education (2004), 23

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See detailNote sous Cour d'appel de Lyon, troisième Chambre, 25 septembre 2003, Georgen
Conac, Pierre-Henri UL

in Revue des Sociétés (2004), (3), 881-881

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See detailLebenslanges Lernen in historischer Perspektive: Drei Beispiele für ein altes Konzept
Oelkers, Jürgen; Casale, Rita; Tröhler, Daniel UL

in Zeitschrift für Pädagogik (2004), 50

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See detailScreening for mutations in synaptotagmin XI in Parkinson's disease.
Glass, A. S.; Huynh, D. P.; Franck, Th et al

in Journal of neural transmission. Supplementum (2004), (68), 21-8

Parkinson's disease (PD) is characterized by selective degeneration of neurons in the substantia nigra and subsequent dysfunction of dopaminergic neurotransmission. Genes identified in familial forms of ... [more ▼]

Parkinson's disease (PD) is characterized by selective degeneration of neurons in the substantia nigra and subsequent dysfunction of dopaminergic neurotransmission. Genes identified in familial forms of PD encode proteins that are linked to the ubiquitin-proteasome system indicating the pathogenic relevance of disturbed protein degradation in PD. Some of them, i.e. alpha-synuclein, parkin and synphilin-1, have been implicated in presynaptic neurotransmission based on their localization in synaptic vesicles. Synaptotagmin XI is linked to the pathogenesis of PD based on its identification as a substrate of the ubiquitin-E3-ligase parkin. Moreover synaptotagmin XI is involved in the maintainance of synaptic function and represents a component of Lewy bodies (LB) in brains of PD patients. Therefore, we performed a detailed mutation analysis of the synaptotagmin XI gene in a large sample of 393 familial and sporadic PD patients. We did not find any disease causing mutations arguing against a major role of mutations in the synaptotagmin XI gene in the pathogenesis of PD. [less ▲]

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See detailSemaphorin 3A stimulates neurite extension and regulates gene expression in PC12 cells.
Schwamborn, Jens Christian UL; Fiore, Roberto; Bagnard, Dominique et al

in Journal of Biological Chemistry (2004), 279(30), 30923-6

The secreted semaphorin 3A (Sema3A) is a member of a large family of proteins that act as guidance signals for axons and dendrites. While the receptors and signaling pathways that mediate the repulsive ... [more ▼]

The secreted semaphorin 3A (Sema3A) is a member of a large family of proteins that act as guidance signals for axons and dendrites. While the receptors and signaling pathways that mediate the repulsive effects of semaphorins are beginning to be understood in some detail, the mechanisms that are responsible for the ability of Sema3A to stimulate the extension of dendrites remain to be elucidated. Here we show that PC12 cells, a model widely used to study neuronal differentiation, can be used to dissect this pathway. Sema3A is as effective as nerve growth factor in stimulating the extension of neurites from PC12 cells. We show that Sema3A is able to regulate gene expression and identify mitochondria as a novel target of Sema3A signaling. Pharmacological block of mitochondrial reactive oxygen species production abolishes the extension of neurites in response to Sema3A. These results show that the characterization of transcripts that are regulated by axon guidance signals may help to identify novel components of their signaling pathways. [less ▲]

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See detailCanonical Brownian motion on the space of univalent functions and resolution of Beltrami equations by a continuity method along stochastic flows
Airault, Hélène; Malliavin, Paul; Thalmaier, Anton UL

in Journal de Mathématiques Pures et Appliquées (2004), 83(8), 955-1018

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See detailSchriftpraxen marokkanischer Frauen in einem französischen Vorstadtviertel.
Weth, Constanze UL

in Lendemains (2004), 114/115

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See detailTime hierarchies in the Escherichia coli carbohydrate uptake and metabolism.
Kremling, A.; Fischer, S.; Sauter, Thomas UL et al

in Bio Systems (2004), 73(1), 57-71

The analysis of metabolic pathways with mathematical models contributes to the better understanding of the behavior of metabolic processes. This paper presents the analysis of a mathematical model for ... [more ▼]

The analysis of metabolic pathways with mathematical models contributes to the better understanding of the behavior of metabolic processes. This paper presents the analysis of a mathematical model for carbohydrate uptake and metabolism in Escherichia coli. It is shown that the dynamic processes cover a broad time span from some milliseconds to several hours. Based on this analysis the fast processes could be described with steady-state characteristic curves. A subsequent robustness analysis of the model parameters shows that the fast part of the system may act as a filter for the slow part of the system; the sensitivities of the fast system are conserved. From these findings it is concluded that the slow part of the system shows some robustness against changes in parameters of the fast subsystem, i.e. if a parameter shows no sensitivity for the fast part of the system, it will also show no sensitivity for the slow part of the system. [less ▲]

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See detailA chameleon chiral polar liquid crystal: Rod-shaped when nematic, bent-shaped when smectic
Lagerwall, Jan UL; Giesselmann, Frank; Wand, Michael D. et al

in Chemistry of Materials (2004), 16(19), 3606-3615

The first antiferroelectric liquid crystal (AFLC) exhibiting a (chiral) nematic phase, a combination which has long been the goal of synthetic chemists working with polar liquid crystals but which at the ... [more ▼]

The first antiferroelectric liquid crystal (AFLC) exhibiting a (chiral) nematic phase, a combination which has long been the goal of synthetic chemists working with polar liquid crystals but which at the same time represents a fundamental contradiction in terms of translational order, was recently reported by Nishiyama and co-workers. We have investi- gated this chiral twin dimer by optic, electrooptic, and dielectric methods and conclude that it is not an ordinary AFLC material, but one where the peculiar properties of bent-core smectics are combined with those of ordinary rod-shaped liquid crystals. The compound exhibits a new type of nematic-smectic phase transition, connected with a change of molecule conformation from rod- to bent-shaped. This also has an important impact on the chiral interactions in the system. Toward the high-temperature end of the smectic phase, the energy balance between bent conformation smectic and straight conformation nematic can be shifted by an electric field such that the transition to the nematic phase with stretched-out molecules can be field-induced. [less ▲]

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See detailSolvation free energies and transfer free energies for amino acids from hydrophobic solution to water solution from a very simple residue model
Gu, Wei UL; Rahi, S. J.; Helms, V.

in Journal of Physical Chemistry B (2004), 108(18), 5806-5814

Solvation free energies of neutral amino acids in water and in chloroform were computed from extensive molecular dynamics simulations using multiconfiguration thermodynamic integration. The values ... [more ▼]

Solvation free energies of neutral amino acids in water and in chloroform were computed from extensive molecular dynamics simulations using multiconfiguration thermodynamic integration. The values computed for the AMBER force field are in very good agreement with available experimental data (rms differences of 5.1 kJ mol(-1) for the solvation free energies and 6.4 kJ mol(-1) for the transfer free energies of amino acids between water and chloroform) and with existing calculations. We derived an additive residue-scale solvation model formulated as the sum of a nonpolar term that is proportional to the molecular surface area and an electrostatic term (Kirkwood-Onsager model) for the hydration free energy of a dipole in a solvated cavity. This model can surprisingly well describe the solvation free energies in water and chloroform as well as the transfer free energies of amino acids between the two solvents when suitably adapted cavity radii are used. Root-mean-square differences of the predicted values with respect to the values calculated from thermodynamic integration are 1.8, 5.9, and 7.7 kJ mol(-1), respectively. [less ▲]

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See detailGenes in familial parkinsonism and their role in sporadic Parkinson's disease.
Krüger, Rejko UL

in Journal of neurology (2004), 251 Suppl 6

For several decades there has been a controversy on the contribution of genetic factors to the pathogenesis of sporadic idiopathic Parkinson's disease (PD). The identification of families in which typical ... [more ▼]

For several decades there has been a controversy on the contribution of genetic factors to the pathogenesis of sporadic idiopathic Parkinson's disease (PD). The identification of families in which typical parkinsonism is inherited as an autosomal dominant or recessive trait sheds light on genes that cause phenotypes resembling sporadic PD. These genes are involved in molecular pathways leading to neurodegeneration and dysfunction of the nigrostriatal system. The present article gives insight into molecular pathways to neurodegeneration deciphered by the functional characterization of five genes identified in inherited forms of typical levodopa-responsive parkinsonism. There is increasing evidence that genes involved in monogenic forms of the disease may act as susceptibility factors also in the common sporadic form of PD. Transgenic animal models based on disease genes identified in monogenic forms of typical parkinsonism replicate important features of PD including protein aggregation and progressive motor symptoms. This implicates novel perspectives for neuroprotective therapeutic approaches that might be beneficial also to sporadic PD. [less ▲]

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See detailUCHL1 is a Parkinson's disease susceptibility gene.
Maraganore, Demetrius M.; Lesnick, Timothy G.; Elbaz, Alexis et al

in Annals of neurology (2004), 55(4), 512-21

The reported inverse association between the S18Y variant of the ubiquitin carboxy-terminal hydrolase L1 (UCHL1) gene and Parkinson's disease (PD) has strong biological plausibility. If confirmed, genetic ... [more ▼]

The reported inverse association between the S18Y variant of the ubiquitin carboxy-terminal hydrolase L1 (UCHL1) gene and Parkinson's disease (PD) has strong biological plausibility. If confirmed, genetic association of this variant with PD may support molecular targeting of the UCHL1 gene and its product as a therapeutic strategy for PD. In this light, we performed a collaborative pooled analysis of individual-level data from all 11 published studies of the UCHL1 S18Y gene variant and PD. There were 1,970 cases and 2,224 unrelated controls. We found a statistically significant inverse association of S18Y with PD. Carriers of the variant allele (Y/Y plus Y/S vs S/S) had an odds ratio (OR) of 0.84 (95% confidence interval [CI], 0.73-0.95) and homozygotes for the variant allele (Y/Y vs S/S plus Y/S) had an OR of 0.71 (95% CI, 0.57-0.88). There was a linear trend in the log OR consistent with a gene dose effect (p = 0.01). The inverse association was most apparent for young cases compared with young controls. There was no evidence for publication bias and the associations remained significant after excluding the first published, hypothesis-generating study. These findings confirm that UCHL1 is a susceptibility gene for PD and a potential target for disease-modifying therapies. [less ▲]

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See detailOptical absorption and electron energy loss spectra of carbon and boron nitride nanotubes: a first-principles approach
Marinopoulos, A. G.; Wirtz, Ludger UL; Marini, A. et al

in Applied Physics A : Materials Science & Processing (2004), 78(8), 1157-1167

We present results for the optical absorption spectra of small-diameter single-walled carbon and boron nitride nanotubes obtained by ab initio calculations in the framework of time-dependent density ... [more ▼]

We present results for the optical absorption spectra of small-diameter single-walled carbon and boron nitride nanotubes obtained by ab initio calculations in the framework of time-dependent density-functional theory. We compare the results with those obtained for the corresponding layered structures, i.e. the graphene and hexagonal boron nitride sheets. In particular, we focus on the role of depolarization effects, anisotropies, and interactions in the excited states. We show that the random phase approximation reproduces well the main features of the spectra when crystal local field effects are correctly included, and discuss to what extent the calculations can be further simplified by extrapolating results obtained for the layered systems to results expected for the tubes. The present results are relevant for the interpretation of data obtained by recent experimental tools for nanotube characterization, such as optical and fluorescence spectroscopies, as well as polarized resonant Raman scattering spectroscopy. We also address electron energy loss spectra in the small-q momentum-transfer limit. In this case, the interlayer and intertube interactions play an enhanced role with respect to optical spectroscopy. [less ▲]

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See detailImpact of layer structure on performance of unpassivated AlGaN/GaN/SiC HEMTs,
Bernát, J.; Wolter, M.; Fox, A. et al

in Electronics Letters (2004), 40(1), 78-80

The performance of unpassivated AlGaN=GaN=SiC HEMTs prepared on different MOVPE grown layer structures is reported. An overall improvement of device characteristics using doped structures in comparison to ... [more ▼]

The performance of unpassivated AlGaN=GaN=SiC HEMTs prepared on different MOVPE grown layer structures is reported. An overall improvement of device characteristics using doped structures in comparison to undoped counterpart is observed. This can be demonstrated by IDS of 0.86 and 1.33 A=mm, gm of 220 and 273 mS=mm, fT of 33 and 43 GHz and fmax of 54 and 61 GHz for 0.3 mm gate length devices on undoped and doped structures, respectively. The DC=pulsed I–V characteristics as well as power measurements show insignificant RF dispersion of HEMTs on doped structures. These results underline the advantage of doped layer structures for preparation of high-performance AlGaN=GaN HEMTs. [less ▲]

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See detailOn the origin of high optical director tilt in a partially fluorinated orthoconic antiferroelectric liquid crystal
Lagerwall, Jan UL; Giesselmann, Frank; Saipa, Alexander et al

in Liquid Crystals (2004), 31(9), 1175-1184

We have investigated the orthoconic antiferroelectric liquid crystal mixture W107 by means of optical, X-ray and calorimetry measurements in order to assess the origin of the unusally high tilt angle ... [more ▼]

We have investigated the orthoconic antiferroelectric liquid crystal mixture W107 by means of optical, X-ray and calorimetry measurements in order to assess the origin of the unusally high tilt angle between the optic axis and the smectic layer normal in this material. The optical birefringence increases strongly below the transition to the tilted phases, showing that the onset of tilt is coupled with a considerable increase in orientational order. The layer spacing in the smectic A (SmA) phase is notably smaller than the extended length of the molecules constituting the mixture, and the shrinkage in smectic C (SmC) and smectic C-a (SmCa) is much less than the optical tilt angle would predict. These observations indicate that the tilting transition in W107 to a large extent follows the asymmetric de Vries diffuse cone model. The molecules are on average considerably tilted with respect to the layer normal already in the SmA phase but the tilting directions are there randomly distributed, giving the phase its uniaxial characteristics. At the transition to the SmC phase, the distribution is biased such that the molecular tilt already present in SmA now gives a contribution to the macroscopic tilt angle. In addition, there is a certain increase of the average tilt angle, leading to a slightly smaller layer thickness in the tilted phases. Analysis of the wide angle scattering data show that the molecular tilt in SmCa is about 20degrees larger than in SmA. The large optical tilt (45degrees) in the SmCa phase thus results from a combination of an increased average molecule tilt and a biasing of tilt direction fluctuations. [less ▲]

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See detailSpin structure of nanocrystalline terbium
Weissmüller, J.; Michels, Andreas UL; Michels, D. et al

in Physical Review. B, Condensed Matter and Materials Physics (2004), 69

We present an experimental study of the magnetic microstructure in the nanocrystalline hard magnet Tb. Field-dependent small-angle neutron scattering (SANS) data are analyzed quantitatively in terms of ... [more ▼]

We present an experimental study of the magnetic microstructure in the nanocrystalline hard magnet Tb. Field-dependent small-angle neutron scattering (SANS) data are analyzed quantitatively in terms of the correlation function of the spin misalignment. We find that up to applied fields of several tesla the magnetization remains “locked in” to the basal planes of the hcp crystal lattice of each individual crystallite, but that the in-plane orientation of the spins is highly nonuniform within each grain. This spin disorder at the nanoscale can be suppressed by a large applied field, but in the remanent state the disorder reduces the magnetization to values considerably below the Stoner limit. In field-dependent SANS, the intragrain spin disorder gives rise to a crossover of the scattering curves, and to the unusual finding that the scattering cross section at small scattering vector increases with increasing magnetic field. As the origin of the internal spin disorder within the grains, we propose an extra magnetic anisotropy energy at small grain size, presumably due to microstrain, a suggestion which is supported by analysis of ac-susceptibility data in the paramagnetic state. Our finding of a reduced remanence at small grain size is contrary to the remanence enhancement that is observed in other nanocrystalline hard magnets. We also report an unusual logarithmic field dependence of the magnetization over wide ranges of the applied field and temperature. [less ▲]

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See detailThe effect of recombinant IgG antibodies against the leucine-33 form of the platelet beta3 integrin (HPA-1a) on platelet function.
Joutsi-Korhonen, Lotta; Preston, Sandy; Smethurst, Peter A. et al

in Thrombosis and haemostasis (2004), 91(4), 743-54

Recombinant HPA-1a antibodies with Fc, mutated to remove destructive effector functions, have been developed as a potential therapy for fetomaternal alloimmune thrombocytopenia (FMAIT), via blockade of ... [more ▼]

Recombinant HPA-1a antibodies with Fc, mutated to remove destructive effector functions, have been developed as a potential therapy for fetomaternal alloimmune thrombocytopenia (FMAIT), via blockade of binding of human HPA-1a polyclonal antibodies to fetal HPA-1a1b platelets. We have assessed the effect of the IgG1 HPA-1a antibody B2G1 and two mutated derivatives in various functional assays in resting and agonist-stimulated platelets of the three HPA-1 genotypes. With HPA-1a1b platelets (fetal genotype), the antibodies did not activate signalling or CD62P expression in resting platelets, did not change in vitro bleeding time (IVBT), and did not inhibit platelet adhesion to collagen in flowing blood. Adhesion of HPA-1a1b platelets to fibrinogen was reduced by 20%, and aggregation induced by ADP by 50%, but collagen-related peptide (CRP-XL)-induced aggregation was normal. With HPA-1a1a platelets, aggregation to both ADP and CRP-XL was inhibited, with total blockade of adhesion to fibrinogen and of IVBT responses. Interestingly, a monovalent antibody fragment with identical specificity had no inhibitory effect on aggregation. In static adhesion assays using human alphaIIbbeta3 or alphaVbeta3 transfectants of HPA-1a (Leu(33)) phenotype, attachment to fibrinogen of the latter but not of the former was completely blocked by the HPA-1a antibodies. These observations are best explained by antibody-mediated blockade of the RGD binding site on beta3 by a mechanism of steric hindrance. As the effect on platelet function is modest with HPA-1a1b (fetal type) platelets, the mutated HPA-1a antibodies described here could be developed further for FMAIT therapy. [less ▲]

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See detailLes Income Deposit Securities
Conac, Pierre-Henri UL

in Revue de Droit Bancaire et Financier (2004)

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See detailEvaluation professionnelle compréhensive du programme obésité en Polynésie Française
Baumann, Michèle UL; Cao, M. M.

in Cahiers de Sociologie et de Démographie Médicales (2004), 44(2), 187-202

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See detailA Note on Compatibility and Entry in a Circular Model of Product Differentiation
Jonard, Nicolas UL; Schenk, Eric

in Economics Bulletin (2004), 12

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See detailNovel functional interaction between the plasma membrane Ca2+ pump 4b and the proapoptotic tumor suppressor Ras-associated factor 1 (RASSF1).
Armesilla, Angel L.; Williams, Judith C.; Buch, Mamta H. et al

in The Journal of biological chemistry (2004), 279(30), 31318-28

Plasma membrane calmodulin-dependent calcium ATPases (PMCAs) are enzymatic systems implicated in the extrusion of calcium from the cell. We and others have previously identified molecular interactions ... [more ▼]

Plasma membrane calmodulin-dependent calcium ATPases (PMCAs) are enzymatic systems implicated in the extrusion of calcium from the cell. We and others have previously identified molecular interactions between the cytoplasmic COOH-terminal end of PMCA and PDZ domain-containing proteins. These interactions suggested a new role for PMCA as a modulator of signal transduction pathways. The existence of other intracellular regions in the PMCA molecule prompted us to investigate the possible participation of other domains in interactions with different partner proteins. A two-hybrid screen of a human fetal heart cDNA library, using the region 652-840 of human PMCA4b (located in the catalytic, second intracellular loop) as bait, revealed a novel interaction between PMCA4b and the tumor suppressor RASSF1, a Ras effector protein involved in H-Ras-mediated apoptosis. Immunofluorescence co-localization, immunoprecipitation, and glutathione S-transferase pull-down experiments performed in mammalian cells provided further confirmation of the physical interaction between the two proteins. The interaction domain has been narrowed down to region 74-123 of RASSF1C (144-193 in RASSF1A) and 652-748 of human PMCA4b. The functionality of this interaction was demonstrated by the inhibition of the epidermal growth factor-dependent activation of the Erk pathway when PMCA4b and RASSF1 were co-expressed. This inhibition was abolished by blocking PMCA/RASSSF1 association with an excess of a green fluorescent protein fusion protein containing the region 50-123 of RASSF1C. This work describes a novel protein-protein interaction involving a domain of PMCA other than the COOH terminus. It suggests a function for PMCA4b as an organizer of macromolecular protein complexes, where PMCA4b could recruit diverse proteins through interaction with different domains. Furthermore, the functional association with RASSF1 indicates a role for PMCA4b in the modulation of Ras-mediated signaling. [less ▲]

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See detailMaking sense of the minus sign or becoming flexible in “negativity”
Vlassis, Joëlle UL

in Learning and Instruction (2004)

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See detail„De coloribus disputandum est”: De mislukte standaardisering van kleuren-televisie in Europa
Fickers, Andreas UL

in Tijdschrift voor Mediageschiedenis (2004), 7(1), 90-117

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See detailThe community of those who have nothing in common. Education and the language of responsibility.
Biesta, Gert UL

in Interchange (2004), 35(3), 307-324

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See detailWhen do prototypes bias person memory? Differential effects of abstraction level
Krolak-Schwerdt, Sabine UL

in European Journal of Social Psychology (2004), 34

Three experiments investigated the operation of prototypical person categories, which were either at a superordinate or at a subordinate level of abstraction, on person memory. In Experiment 1, a ... [more ▼]

Three experiments investigated the operation of prototypical person categories, which were either at a superordinate or at a subordinate level of abstraction, on person memory. In Experiment 1, a recognition memory experiment, subjects received person attributes describing fictional target persons, each description pertaining to one of the two abstraction levels. Distractors in the recognition test varied in degree of relatedness to a prototypical category. Distractors that were related to the corresponding category were falsely recognized, if the category was at a superordinate level, but not for a subordinate category. This revealed a significant bias in recognition toward conceptually related but nonpresented items only at the superordinate level. In Experiment 2 which used a conceptual priming procedure subjects responded faster to distractor items related to a superordinate category than to those related to a subordinate category. Experiment 3 replicated the difference between levels of abstraction when subjects’ task was to recall rather than to recognize the presented attributes. The findings imply that person categories at different levels of abstraction operate differentially on person memory and restrict assumptions from prototype theory to a superordinate level. [less ▲]

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See detailZur Wettbewerbsfähigkeit der Sozialen Marktwirtschaft im Zeitalter der Globalisierung
Klump, Rainer UL

in List-Forum für Wirtschafts- und Finanzpolitik (2004)

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See detailDécision de la Cour de cassation, 1ère Civ., 17 février 2004
Cuniberti, Gilles UL

in Clunet (2004)

Contrôle de la compétence du juge étranger

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See detailConformational subspace in simulation of early-stage protein folding
Jurkowski, Wiktor UL; Brylinski, Michal; Konieczny, Leszek et al

in Proteins (2004), 55(1), 115-27

A probability calculus was used to simulate the early stages of protein folding in ab initio structure prediction. The probabilities of particular phi and psi angles for each of 20 amino acids as they ... [more ▼]

A probability calculus was used to simulate the early stages of protein folding in ab initio structure prediction. The probabilities of particular phi and psi angles for each of 20 amino acids as they occur in crystal forms of proteins were used to calculate the amount of information necessary for the occurrence of given phi and psi angles to be predicted. It was found that the amount of information needed to predict phi and psi angles with 5 degrees precision is much higher than the amount of information actually carried by individual amino acids in the polypeptide chain. To handle this problem, a limited conformational space for the preliminary search for optimal polypeptide structure is proposed based on a simplified geometrical model of the polypeptide chain and on the probability calculus. These two models, geometric and probabilistic, based on different sources, yield a common conclusion concerning how a limited conformational space can represent an early stage of polypeptide chain-folding simulation. The ribonuclease molecule was used to test the limited conformational space as a tool for modeling early-stage folding. [less ▲]

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See detail(-)-isopinocampheol substituted mesogens: An investigation of the effect of bulky terminal groups in chiral smectic liquid crystals
Yates, Chris; Lagerwall, Jan UL; Nobili, Maurizio et al

in Ferroelectrics (2004), 311

A ferroelectric liquid crystal with an end-substituted (-)-isopinocampheol (IPC) group has been studied in isolation and in mixtures with the antiferroelectric compound EHPOCBC. The samples were studied ... [more ▼]

A ferroelectric liquid crystal with an end-substituted (-)-isopinocampheol (IPC) group has been studied in isolation and in mixtures with the antiferroelectric compound EHPOCBC. The samples were studied with respect to electroclinic coefficients, tilt angles, X-ray layer spacing, dielectric permittivity, spontaneous polarisation and relative birefringence under an applied field. In the pure isopinocampheol substituted compound, the SmA-SmC phase transition appears strongly first order and is associated with a significant increase in effective birefringence. The smectic layer spacing decreases below the transition approximately with the optical tilt. On increased EHPOCBC concentration the change in birefringence across the transition diminishes, until the point at which the mixture adopts an anticlinic SmC(A) phase, and the expected decrease in birefringence is observed. There is very little change in birefringence with field for the IPC compound, whilst EHPOCBC shows a marked increase with increasing field, for a few degrees above the phase transition. The results are analyzed with respect to two models. In one it is proposed that the bulky IPC group disorders the SmA phase by introducing undulations in the smectic layer. These undulations may disappear in the SmC phase due to an antiparallel arrangement of neighbouring molecules. In the other model the bent shape of the mesogen as a whole plays a crucial role in changing the optical properties at the SmA-SmC transition, due to the biased rotation around the molecular axis of inertia. [less ▲]

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See detailEntreprendre au féminin: Une réalité multiple et des attentes différenciées
Cornet, Annie; Constantinidis, Christina UL

in Revue Française de Gestion (2004), 30(151), 191-204

Les femmes optent de plus en plus souvent pour le statut d’indépendante et, trop rarement encore, pour le statut de « chef d’entreprise ». Cet article cherche à comprendre les facteurs qui semblent guider ... [more ▼]

Les femmes optent de plus en plus souvent pour le statut d’indépendante et, trop rarement encore, pour le statut de « chef d’entreprise ». Cet article cherche à comprendre les facteurs qui semblent guider leur choix, le type d’activités vers lesquelles elles s’orientent, les difficultés qu’elles rencontrent ainsi que leurs succès et les stratégies mises en œuvre pour réussir leur projet. Cet article est fondé sur une recherche quantitative et qualitative qui permet de montrer que le projet entrepreneurial des femmes a certes des similarités avec celui des hommes mais certains choix et stratégies restent marqués par des rapports sociaux de genre. [less ▲]

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See detailWelbevinden van Europese ouderen
Drooglever-Fortuijn, Joos; Ferring, Dieter UL; van der Meer, M. et al

in Geron (2004), 6(4), 14-18

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See detailPTGL--a web-based database application for protein topologies.
May, Patrick UL; Barthel, Stefan; Koch, Ina

in Bioinformatics (2004), 20(17), 3277-9

Protein Topology Graph Library (PTGL) is a database application for the representation and retrieval of protein topologies. Protein topologies are based on a graph-theoretical protein model at secondary ... [more ▼]

Protein Topology Graph Library (PTGL) is a database application for the representation and retrieval of protein topologies. Protein topologies are based on a graph-theoretical protein model at secondary structure level. Different views on protein topology are given by four linear notations for their characterization. Protein topologies can be derived at different description levels considering alpha- and beta-structures. The on-line search tool is based on an object-relational database and provides a query browser for data interrogation by string patterns, keyword queries and sequence similarity. Protein topologies are represented both as schematic diagrams and as three-dimensional images. [less ▲]

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See detailKnizhnik-Zamolodchikov equations for positive genus and Krichever-Novikov algebras
Schlichenmaier, Martin UL; Sheinman, Oleg K.

in Russian Mathematical Surveys (2004), 59(4), 737-770

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See detailEducation, accountability and the ethical demand. Can the democratic potential of accountability be regained?
Biesta, Gert UL

in Educational Theory (2004), 54(3), 233-250

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See detailCharacteristic magnetic length-scales in Vitroperm—Combining Kerr microscopy and small-angle neutron scattering
Grob, A.; Saranu, S.; Herr, U. et al

in Physica Status Solidi A. Applied Research (2004), 201

We present a study of the magnetic-field dependence of the magnetic microstructure of the nanocrystalline soft magnet Vitroperm (Fe73Si16B7Nb3Cu1), which was treated so as to exhibit a macroscopic ... [more ▼]

We present a study of the magnetic-field dependence of the magnetic microstructure of the nanocrystalline soft magnet Vitroperm (Fe73Si16B7Nb3Cu1), which was treated so as to exhibit a macroscopic magnetic anisotropy. The samples were analysed using Kerr microscopy and small-angle neutron scattering (SANS). As the applied magnetic field is decreased starting from saturation, we find that two processes occur independently: the formation of a domain structure with the net magnetisation of the domains aligned along the macroscopic easy axis and the increase in magnitude of static, nanometer-scale fluctuations of the spin orientation. The domain structure observations from Kerr microscopy are in excellent agreement with the results of the SANS experiments. [less ▲]

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See detailSNURF-SNRPN and UBE3A transcript levels in patients with Angelman syndrome
Runte, Maren UL; Kroisel, PM; Gillessen-Kaesbach, G et al

in Human Genetics (2004), 114(6), 553-561

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See detailComplexity,representation and the epistemology of schooling
Osberg,D.C.; Biesta, Gert UL

in Proceedings of the 2003 Complexity Science and Educational Research Conference (2004)

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See detailDer Computer – "Nur" Werkzeug oder den Unterricht veränderndes Medium?
Sunnen, Patrick UL

in Online-Zeitschrift Grundschulforschung (2004), (8),

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See detailIndication of the uplift of the Ardenne in long-term gravity variations in Membach (Belgium)
Francis, Olivier UL; Van Camp, Michel; van Dam, Tonie UL et al

in Geophysical Journal International (2004), 158(1), 346-352

We report on the results of 7 yr of collocated gravity observations made with an FG5 abso- lute (AG) gravimeter and a GWR C-Series superconducting gravimeter (SG) located at the Membach Geophysical ... [more ▼]

We report on the results of 7 yr of collocated gravity observations made with an FG5 abso- lute (AG) gravimeter and a GWR C-Series superconducting gravimeter (SG) located at the Membach Geophysical Station in eastern Belgium. The SG gravity residuals track changes in gravity periodically observed by the AG, at the microgal level. Further, in the SG resid- ual signal we distinguish a quasi-seasonal term that can be mostly explained by variations in local water storage effects. In the AG time-series we observe a small trend in the gravity of −0.6 ± 0.1 μGal yr−1 perhaps indicating that the Membach Station is being displaced up- wards by about 3.0 mm yr−1. An uplift of the region is confirmed by Global Positioning System (GPS) measurements performed 3 km away. We are able to explain the features in the gravity time-series in terms of water storage variability, post-glacial rebound and tectonic activity. [less ▲]

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See detailLa respiration : Comparaison entre les représentations des élèves et l’évolution historique du concept
Flammang, Cécile; Vlassis, Joëlle UL; Crahay, Marcel

in Informations Pédagogiques (2004), 55

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See detailBook review of : B. NOAK, Politische Auffassungen im niederländischen Drama des 17. Jahrhunderts, 2002
Weis, Monique UL

in Revue Belge de Philologie et d'Histoire (2004), 82

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See detailExtended mutation analysis and association studies of Nurr1 (NR4A2) in Parkinson disease.
Hering, R.; Petrovic, S.; Mietz, E.-M. et al

in Neurology (2004), 62(7), 1231-2

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See detailMeasurements and particle resolved modelling of the thermo-and fluid dynamics of a packed bed.
Peters, Bernhard UL; Bruch, Christian; Schröder, E.

in Journal of Analytical and Applied Pyrolysis (2004), (70), 211-233

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See detailDepression, perceived control, and life satisfaction in university students from central-eastern and western Europe
Wardle, Jane; Steptoe, Andrew; Guliš, Gabriel et al

in International Journal of Behavioral Medicine (2004), 11

The poor health and psychological well-being of people in the former socialist states of Centeral-Eastern Europe are of serious concern and may be related to low perceived control. We compared depressive ... [more ▼]

The poor health and psychological well-being of people in the former socialist states of Centeral-Eastern Europe are of serious concern and may be related to low perceived control. We compared depressive symptoms, life satisfaction, and self-rated health in 3,571 male and female university students from 5 Western European countries and 4,793 students from 5 Central-Eastern European countries. Depression scores (short Beck Depression Inventory; Beck & Beck, 1972) were higher in Central-Eastern than Western European samples. The prevalence of low life satisfaction was also greater in Central-Eastern Europeans, but ratings of self-rated health did not differ. Ratings of perceived control were diminished, but sense of mastery and internal health locus of control were higher in Central-Eastern Europe. Depression and low life satisfaction were associated with low perceived control and mastery and with strong beliefs in the influence of chance over health. However, taking these factors into account did not explain the East-West difference in depressive symptoms and low life satisfaction. [less ▲]

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See detailThe application of two-dimensional polyacrylamide gel electrophoresis and downstream analyses to a mixed community of prokaryotic microorganisms
Wilmes, Paul UL; Bond, P. L.

in Environmental Microbiology (2004), 6(9), 911-920

In the post-genomic era, the focus of numerous researchers has moved to studying the functional products of gene expression. In microbiology, these 'omic' approaches have largely been limited to pure ... [more ▼]

In the post-genomic era, the focus of numerous researchers has moved to studying the functional products of gene expression. In microbiology, these 'omic' approaches have largely been limited to pure cultures of microorganisms. Consequently, they do not provide information on gene expression in a complex mixture of microorganisms as found in the environment. Our method enabled the successful extraction and purification of the entire proteome from a laboratory-scale activated sludge system optimized for enhanced biological phosphorus removal, its separation by two-dimensional polyacrylamide gel electrophoresis and the mapping of this metaproteome. Highly expressed protein spots were excised and identified using quadrupole time-of-flight mass spectrometry with de novo peptide sequencing. The proteins isolated were putatively identified as an outer membrane protein (porin), an acetyl coenzyme A acetyltransferase and a protein component of an ABC-type branched-chain amino acid transport system. These proteins possibly stem from the dominant and uncultured Rhodocyclus-type polyphosphate-accumulating organism in the activated sludge. We propose the term 'metaproteomics' for the large-scale characterization of the entire protein complement of environmental microbiota at a given point in time. [less ▲]

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See detailModeling and experimental validation of the signal transduction via the Escherichia coli sucrose phospho transferase system.
Sauter, Thomas UL; Gilles, E. D.

in Journal of Biotechnology (2004), 110(2), 181-99

Bacterial signal processing was investigated concerning the sucrose phosphotransferase system (sucrose PTS) in the bacterium Escherichia coli as an example. The about 20 different phosphotransferase ... [more ▼]

Bacterial signal processing was investigated concerning the sucrose phosphotransferase system (sucrose PTS) in the bacterium Escherichia coli as an example. The about 20 different phosphotransferase systems (PTSs) of the cell fulfill besides the transport of various carbohydrates, also the function of one signal processing system. Extra- and intracellular signals are converted within the PTS protein chain to important regulatory signals affecting, e.g. carbon metabolism and chemotaxis. A detailed dynamical model of the sucrose PTS was developed describing transport and signal processing function. It was formulated using a detailed description of complex formation and phosphate transfer between the chain proteins. Model parameters were taken from literature or were identified with own experiments. Simulation studies together with experimental hints showed that the dynamic behavior of phosphate transfer in the PTS runs within 1 s. Therefore a description of steady state characteristics is sufficient for describing the signaling properties of the sucrose PTS. A steady state characteristic field describes the degree of phosphorylation of the PTS protein EIIACrr as a function of the input variables extracellular sucrose concentration and intracellular phosphoenolpyruvate (PEP):pyruvate ratio. The model has been validated with different experiments performed in a CSTR using a sucrose positive E. coli W3110 derivative. A method for determining intracellular metabolite concentrations has been developed. A sample preparation technique using a boiling ethanol buffer solution was successfully applied. The PTS output signal degree of phosphorylation of EIIACrr was also measured. Steady state conditions with varying dilution rate and dissolved oxygen concentration and dynamical variations applying different stimuli to the culture were considered. Pulse, and stop feeding experiments with limiting sucrose concentrations were performed. Simulation and experimental results matched well. The same holds for the expanded sucrose PTS and glycolysis model. [less ▲]

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See detailThe spatial Solow model
Camacho, Camen; Zou, Benteng UL

in Economics Bulletin (2004)

In this paper, we solve a Solow model in continuous time and space. We prove the existence of a solution to the problem and its convergence to a stationary solution. The simulations of various scenario in ... [more ▼]

In this paper, we solve a Solow model in continuous time and space. We prove the existence of a solution to the problem and its convergence to a stationary solution. The simulations of various scenario in the last section of the paper illustrates the convergence issue. [less ▲]

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